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Commit | Line | Data |
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bcea3f96 | 1 | // SPDX-License-Identifier: GPL-2.0 |
bc0c38d1 SR |
2 | /* |
3 | * ring buffer based function tracer | |
4 | * | |
2b6080f2 | 5 | * Copyright (C) 2007-2012 Steven Rostedt <srostedt@redhat.com> |
bc0c38d1 SR |
6 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> |
7 | * | |
8 | * Originally taken from the RT patch by: | |
9 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
10 | * | |
11 | * Based on code from the latency_tracer, that is: | |
12 | * Copyright (C) 2004-2006 Ingo Molnar | |
6d49e352 | 13 | * Copyright (C) 2004 Nadia Yvette Chambers |
bc0c38d1 | 14 | */ |
2cadf913 | 15 | #include <linux/ring_buffer.h> |
273b281f | 16 | #include <generated/utsrelease.h> |
2cadf913 SR |
17 | #include <linux/stacktrace.h> |
18 | #include <linux/writeback.h> | |
bc0c38d1 | 19 | #include <linux/kallsyms.h> |
17911ff3 | 20 | #include <linux/security.h> |
bc0c38d1 | 21 | #include <linux/seq_file.h> |
3f5a54e3 | 22 | #include <linux/notifier.h> |
2cadf913 | 23 | #include <linux/irqflags.h> |
bc0c38d1 | 24 | #include <linux/debugfs.h> |
8434dc93 | 25 | #include <linux/tracefs.h> |
4c11d7ae | 26 | #include <linux/pagemap.h> |
bc0c38d1 SR |
27 | #include <linux/hardirq.h> |
28 | #include <linux/linkage.h> | |
29 | #include <linux/uaccess.h> | |
76c813e2 | 30 | #include <linux/vmalloc.h> |
bc0c38d1 SR |
31 | #include <linux/ftrace.h> |
32 | #include <linux/module.h> | |
33 | #include <linux/percpu.h> | |
2cadf913 | 34 | #include <linux/splice.h> |
3f5a54e3 | 35 | #include <linux/kdebug.h> |
5f0c6c03 | 36 | #include <linux/string.h> |
f76180bc | 37 | #include <linux/mount.h> |
7e53bd42 | 38 | #include <linux/rwsem.h> |
5a0e3ad6 | 39 | #include <linux/slab.h> |
bc0c38d1 SR |
40 | #include <linux/ctype.h> |
41 | #include <linux/init.h> | |
f39650de | 42 | #include <linux/panic_notifier.h> |
2a2cc8f7 | 43 | #include <linux/poll.h> |
b892e5c8 | 44 | #include <linux/nmi.h> |
bc0c38d1 | 45 | #include <linux/fs.h> |
478409dd | 46 | #include <linux/trace.h> |
3fd49c9e | 47 | #include <linux/sched/clock.h> |
8bd75c77 | 48 | #include <linux/sched/rt.h> |
91edde2e VRB |
49 | #include <linux/fsnotify.h> |
50 | #include <linux/irq_work.h> | |
51 | #include <linux/workqueue.h> | |
86387f7e | 52 | |
bc0c38d1 | 53 | #include "trace.h" |
f0868d1e | 54 | #include "trace_output.h" |
bc0c38d1 | 55 | |
73c5162a SR |
56 | /* |
57 | * On boot up, the ring buffer is set to the minimum size, so that | |
58 | * we do not waste memory on systems that are not using tracing. | |
59 | */ | |
55034cd6 | 60 | bool ring_buffer_expanded; |
73c5162a | 61 | |
8e1b82e0 FW |
62 | /* |
63 | * We need to change this state when a selftest is running. | |
ff32504f FW |
64 | * A selftest will lurk into the ring-buffer to count the |
65 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 66 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
67 | * at the same time, giving false positive or negative results. |
68 | */ | |
8e1b82e0 | 69 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 70 | |
b2821ae6 | 71 | /* |
60efe21e MH |
72 | * If boot-time tracing including tracers/events via kernel cmdline |
73 | * is running, we do not want to run SELFTEST. | |
b2821ae6 | 74 | */ |
020e5f85 | 75 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 76 | |
60efe21e MH |
77 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
78 | void __init disable_tracing_selftest(const char *reason) | |
79 | { | |
80 | if (!tracing_selftest_disabled) { | |
81 | tracing_selftest_disabled = true; | |
82 | pr_info("Ftrace startup test is disabled due to %s\n", reason); | |
83 | } | |
84 | } | |
85 | #endif | |
86 | ||
0daa2302 SRRH |
87 | /* Pipe tracepoints to printk */ |
88 | struct trace_iterator *tracepoint_print_iter; | |
89 | int tracepoint_printk; | |
f3860136 | 90 | static bool tracepoint_printk_stop_on_boot __initdata; |
42391745 | 91 | static DEFINE_STATIC_KEY_FALSE(tracepoint_printk_key); |
0daa2302 | 92 | |
adf9f195 FW |
93 | /* For tracers that don't implement custom flags */ |
94 | static struct tracer_opt dummy_tracer_opt[] = { | |
95 | { } | |
96 | }; | |
97 | ||
8c1a49ae SRRH |
98 | static int |
99 | dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) | |
adf9f195 FW |
100 | { |
101 | return 0; | |
102 | } | |
0f048701 | 103 | |
7ffbd48d SR |
104 | /* |
105 | * To prevent the comm cache from being overwritten when no | |
106 | * tracing is active, only save the comm when a trace event | |
107 | * occurred. | |
108 | */ | |
d914ba37 | 109 | static DEFINE_PER_CPU(bool, trace_taskinfo_save); |
7ffbd48d | 110 | |
0f048701 SR |
111 | /* |
112 | * Kill all tracing for good (never come back). | |
113 | * It is initialized to 1 but will turn to zero if the initialization | |
114 | * of the tracer is successful. But that is the only place that sets | |
115 | * this back to zero. | |
116 | */ | |
4fd27358 | 117 | static int tracing_disabled = 1; |
0f048701 | 118 | |
955b61e5 | 119 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 120 | |
944ac425 SR |
121 | /* |
122 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
123 | * | |
124 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
125 | * is set, then ftrace_dump is called. This will output the contents | |
126 | * of the ftrace buffers to the console. This is very useful for | |
127 | * capturing traces that lead to crashes and outputing it to a | |
128 | * serial console. | |
129 | * | |
130 | * It is default off, but you can enable it with either specifying | |
131 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
132 | * /proc/sys/kernel/ftrace_dump_on_oops |
133 | * Set 1 if you want to dump buffers of all CPUs | |
134 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 135 | */ |
cecbca96 FW |
136 | |
137 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 138 | |
de7edd31 SRRH |
139 | /* When set, tracing will stop when a WARN*() is hit */ |
140 | int __disable_trace_on_warning; | |
141 | ||
681bec03 JL |
142 | #ifdef CONFIG_TRACE_EVAL_MAP_FILE |
143 | /* Map of enums to their values, for "eval_map" file */ | |
23bf8cb8 | 144 | struct trace_eval_map_head { |
9828413d SRRH |
145 | struct module *mod; |
146 | unsigned long length; | |
147 | }; | |
148 | ||
23bf8cb8 | 149 | union trace_eval_map_item; |
9828413d | 150 | |
23bf8cb8 | 151 | struct trace_eval_map_tail { |
9828413d SRRH |
152 | /* |
153 | * "end" is first and points to NULL as it must be different | |
00f4b652 | 154 | * than "mod" or "eval_string" |
9828413d | 155 | */ |
23bf8cb8 | 156 | union trace_eval_map_item *next; |
9828413d SRRH |
157 | const char *end; /* points to NULL */ |
158 | }; | |
159 | ||
1793ed93 | 160 | static DEFINE_MUTEX(trace_eval_mutex); |
9828413d SRRH |
161 | |
162 | /* | |
23bf8cb8 | 163 | * The trace_eval_maps are saved in an array with two extra elements, |
9828413d SRRH |
164 | * one at the beginning, and one at the end. The beginning item contains |
165 | * the count of the saved maps (head.length), and the module they | |
166 | * belong to if not built in (head.mod). The ending item contains a | |
681bec03 | 167 | * pointer to the next array of saved eval_map items. |
9828413d | 168 | */ |
23bf8cb8 | 169 | union trace_eval_map_item { |
00f4b652 | 170 | struct trace_eval_map map; |
23bf8cb8 JL |
171 | struct trace_eval_map_head head; |
172 | struct trace_eval_map_tail tail; | |
9828413d SRRH |
173 | }; |
174 | ||
23bf8cb8 | 175 | static union trace_eval_map_item *trace_eval_maps; |
681bec03 | 176 | #endif /* CONFIG_TRACE_EVAL_MAP_FILE */ |
9828413d | 177 | |
9c5b9d3d | 178 | int tracing_set_tracer(struct trace_array *tr, const char *buf); |
bcee5278 SRV |
179 | static void ftrace_trace_userstack(struct trace_array *tr, |
180 | struct trace_buffer *buffer, | |
36590c50 | 181 | unsigned int trace_ctx); |
b2821ae6 | 182 | |
ee6c2c1b LZ |
183 | #define MAX_TRACER_SIZE 100 |
184 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 185 | static char *default_bootup_tracer; |
d9e54076 | 186 | |
55034cd6 SRRH |
187 | static bool allocate_snapshot; |
188 | ||
1beee96b | 189 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 190 | { |
67012ab1 | 191 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 192 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 193 | /* We are using ftrace early, expand it */ |
55034cd6 | 194 | ring_buffer_expanded = true; |
d9e54076 PZ |
195 | return 1; |
196 | } | |
1beee96b | 197 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 198 | |
944ac425 SR |
199 | static int __init set_ftrace_dump_on_oops(char *str) |
200 | { | |
2db7ab6b | 201 | if (*str++ != '=' || !*str || !strcmp("1", str)) { |
cecbca96 FW |
202 | ftrace_dump_on_oops = DUMP_ALL; |
203 | return 1; | |
204 | } | |
205 | ||
2db7ab6b | 206 | if (!strcmp("orig_cpu", str) || !strcmp("2", str)) { |
cecbca96 FW |
207 | ftrace_dump_on_oops = DUMP_ORIG; |
208 | return 1; | |
209 | } | |
210 | ||
211 | return 0; | |
944ac425 SR |
212 | } |
213 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 214 | |
de7edd31 SRRH |
215 | static int __init stop_trace_on_warning(char *str) |
216 | { | |
933ff9f2 LCG |
217 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) |
218 | __disable_trace_on_warning = 1; | |
de7edd31 SRRH |
219 | return 1; |
220 | } | |
933ff9f2 | 221 | __setup("traceoff_on_warning", stop_trace_on_warning); |
de7edd31 | 222 | |
3209cff4 | 223 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
224 | { |
225 | allocate_snapshot = true; | |
226 | /* We also need the main ring buffer expanded */ | |
227 | ring_buffer_expanded = true; | |
228 | return 1; | |
229 | } | |
3209cff4 | 230 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 231 | |
7bcfaf54 SR |
232 | |
233 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
7bcfaf54 SR |
234 | |
235 | static int __init set_trace_boot_options(char *str) | |
236 | { | |
67012ab1 | 237 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
238 | return 0; |
239 | } | |
240 | __setup("trace_options=", set_trace_boot_options); | |
241 | ||
e1e232ca SR |
242 | static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; |
243 | static char *trace_boot_clock __initdata; | |
244 | ||
245 | static int __init set_trace_boot_clock(char *str) | |
246 | { | |
247 | strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); | |
248 | trace_boot_clock = trace_boot_clock_buf; | |
249 | return 0; | |
250 | } | |
251 | __setup("trace_clock=", set_trace_boot_clock); | |
252 | ||
0daa2302 SRRH |
253 | static int __init set_tracepoint_printk(char *str) |
254 | { | |
255 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) | |
256 | tracepoint_printk = 1; | |
257 | return 1; | |
258 | } | |
259 | __setup("tp_printk", set_tracepoint_printk); | |
de7edd31 | 260 | |
f3860136 SRV |
261 | static int __init set_tracepoint_printk_stop(char *str) |
262 | { | |
263 | tracepoint_printk_stop_on_boot = true; | |
264 | return 1; | |
265 | } | |
266 | __setup("tp_printk_stop_on_boot", set_tracepoint_printk_stop); | |
267 | ||
a5a1d1c2 | 268 | unsigned long long ns2usecs(u64 nsec) |
bc0c38d1 SR |
269 | { |
270 | nsec += 500; | |
271 | do_div(nsec, 1000); | |
272 | return nsec; | |
273 | } | |
274 | ||
8ab7a2b7 TZ |
275 | static void |
276 | trace_process_export(struct trace_export *export, | |
277 | struct ring_buffer_event *event, int flag) | |
278 | { | |
279 | struct trace_entry *entry; | |
280 | unsigned int size = 0; | |
281 | ||
282 | if (export->flags & flag) { | |
283 | entry = ring_buffer_event_data(event); | |
284 | size = ring_buffer_event_length(event); | |
285 | export->write(export, entry, size); | |
286 | } | |
287 | } | |
288 | ||
289 | static DEFINE_MUTEX(ftrace_export_lock); | |
290 | ||
291 | static struct trace_export __rcu *ftrace_exports_list __read_mostly; | |
292 | ||
293 | static DEFINE_STATIC_KEY_FALSE(trace_function_exports_enabled); | |
294 | static DEFINE_STATIC_KEY_FALSE(trace_event_exports_enabled); | |
458999c6 | 295 | static DEFINE_STATIC_KEY_FALSE(trace_marker_exports_enabled); |
8ab7a2b7 TZ |
296 | |
297 | static inline void ftrace_exports_enable(struct trace_export *export) | |
298 | { | |
299 | if (export->flags & TRACE_EXPORT_FUNCTION) | |
300 | static_branch_inc(&trace_function_exports_enabled); | |
301 | ||
302 | if (export->flags & TRACE_EXPORT_EVENT) | |
303 | static_branch_inc(&trace_event_exports_enabled); | |
458999c6 TZ |
304 | |
305 | if (export->flags & TRACE_EXPORT_MARKER) | |
306 | static_branch_inc(&trace_marker_exports_enabled); | |
8ab7a2b7 TZ |
307 | } |
308 | ||
309 | static inline void ftrace_exports_disable(struct trace_export *export) | |
310 | { | |
311 | if (export->flags & TRACE_EXPORT_FUNCTION) | |
312 | static_branch_dec(&trace_function_exports_enabled); | |
313 | ||
314 | if (export->flags & TRACE_EXPORT_EVENT) | |
315 | static_branch_dec(&trace_event_exports_enabled); | |
458999c6 TZ |
316 | |
317 | if (export->flags & TRACE_EXPORT_MARKER) | |
318 | static_branch_dec(&trace_marker_exports_enabled); | |
8ab7a2b7 TZ |
319 | } |
320 | ||
321 | static void ftrace_exports(struct ring_buffer_event *event, int flag) | |
322 | { | |
323 | struct trace_export *export; | |
324 | ||
325 | preempt_disable_notrace(); | |
326 | ||
327 | export = rcu_dereference_raw_check(ftrace_exports_list); | |
328 | while (export) { | |
329 | trace_process_export(export, event, flag); | |
330 | export = rcu_dereference_raw_check(export->next); | |
331 | } | |
332 | ||
333 | preempt_enable_notrace(); | |
334 | } | |
335 | ||
336 | static inline void | |
337 | add_trace_export(struct trace_export **list, struct trace_export *export) | |
338 | { | |
339 | rcu_assign_pointer(export->next, *list); | |
340 | /* | |
341 | * We are entering export into the list but another | |
342 | * CPU might be walking that list. We need to make sure | |
343 | * the export->next pointer is valid before another CPU sees | |
344 | * the export pointer included into the list. | |
345 | */ | |
346 | rcu_assign_pointer(*list, export); | |
347 | } | |
348 | ||
349 | static inline int | |
350 | rm_trace_export(struct trace_export **list, struct trace_export *export) | |
351 | { | |
352 | struct trace_export **p; | |
353 | ||
354 | for (p = list; *p != NULL; p = &(*p)->next) | |
355 | if (*p == export) | |
356 | break; | |
357 | ||
358 | if (*p != export) | |
359 | return -1; | |
360 | ||
361 | rcu_assign_pointer(*p, (*p)->next); | |
362 | ||
363 | return 0; | |
364 | } | |
365 | ||
366 | static inline void | |
367 | add_ftrace_export(struct trace_export **list, struct trace_export *export) | |
368 | { | |
369 | ftrace_exports_enable(export); | |
370 | ||
371 | add_trace_export(list, export); | |
372 | } | |
373 | ||
374 | static inline int | |
375 | rm_ftrace_export(struct trace_export **list, struct trace_export *export) | |
376 | { | |
377 | int ret; | |
378 | ||
379 | ret = rm_trace_export(list, export); | |
380 | ftrace_exports_disable(export); | |
381 | ||
382 | return ret; | |
383 | } | |
384 | ||
385 | int register_ftrace_export(struct trace_export *export) | |
386 | { | |
387 | if (WARN_ON_ONCE(!export->write)) | |
388 | return -1; | |
389 | ||
390 | mutex_lock(&ftrace_export_lock); | |
391 | ||
392 | add_ftrace_export(&ftrace_exports_list, export); | |
393 | ||
394 | mutex_unlock(&ftrace_export_lock); | |
395 | ||
396 | return 0; | |
397 | } | |
398 | EXPORT_SYMBOL_GPL(register_ftrace_export); | |
399 | ||
400 | int unregister_ftrace_export(struct trace_export *export) | |
401 | { | |
402 | int ret; | |
403 | ||
404 | mutex_lock(&ftrace_export_lock); | |
405 | ||
406 | ret = rm_ftrace_export(&ftrace_exports_list, export); | |
407 | ||
408 | mutex_unlock(&ftrace_export_lock); | |
409 | ||
410 | return ret; | |
411 | } | |
412 | EXPORT_SYMBOL_GPL(unregister_ftrace_export); | |
413 | ||
983f938a SRRH |
414 | /* trace_flags holds trace_options default values */ |
415 | #define TRACE_DEFAULT_FLAGS \ | |
416 | (FUNCTION_DEFAULT_FLAGS | \ | |
417 | TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | \ | |
418 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | \ | |
419 | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | \ | |
99e22ce7 SRV |
420 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | \ |
421 | TRACE_ITER_HASH_PTR) | |
983f938a | 422 | |
16270145 SRRH |
423 | /* trace_options that are only supported by global_trace */ |
424 | #define TOP_LEVEL_TRACE_FLAGS (TRACE_ITER_PRINTK | \ | |
425 | TRACE_ITER_PRINTK_MSGONLY | TRACE_ITER_RECORD_CMD) | |
426 | ||
20550622 SRRH |
427 | /* trace_flags that are default zero for instances */ |
428 | #define ZEROED_TRACE_FLAGS \ | |
1e10486f | 429 | (TRACE_ITER_EVENT_FORK | TRACE_ITER_FUNC_FORK) |
16270145 | 430 | |
4fcdae83 | 431 | /* |
67d04bb2 JF |
432 | * The global_trace is the descriptor that holds the top-level tracing |
433 | * buffers for the live tracing. | |
4fcdae83 | 434 | */ |
983f938a SRRH |
435 | static struct trace_array global_trace = { |
436 | .trace_flags = TRACE_DEFAULT_FLAGS, | |
437 | }; | |
bc0c38d1 | 438 | |
ae63b31e | 439 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 440 | |
ff451961 SRRH |
441 | int trace_array_get(struct trace_array *this_tr) |
442 | { | |
443 | struct trace_array *tr; | |
444 | int ret = -ENODEV; | |
445 | ||
446 | mutex_lock(&trace_types_lock); | |
447 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
448 | if (tr == this_tr) { | |
449 | tr->ref++; | |
450 | ret = 0; | |
451 | break; | |
452 | } | |
453 | } | |
454 | mutex_unlock(&trace_types_lock); | |
455 | ||
456 | return ret; | |
457 | } | |
458 | ||
459 | static void __trace_array_put(struct trace_array *this_tr) | |
460 | { | |
461 | WARN_ON(!this_tr->ref); | |
462 | this_tr->ref--; | |
463 | } | |
464 | ||
28879787 DI |
465 | /** |
466 | * trace_array_put - Decrement the reference counter for this trace array. | |
557d50e7 | 467 | * @this_tr : pointer to the trace array |
28879787 DI |
468 | * |
469 | * NOTE: Use this when we no longer need the trace array returned by | |
470 | * trace_array_get_by_name(). This ensures the trace array can be later | |
471 | * destroyed. | |
472 | * | |
473 | */ | |
ff451961 SRRH |
474 | void trace_array_put(struct trace_array *this_tr) |
475 | { | |
28879787 DI |
476 | if (!this_tr) |
477 | return; | |
478 | ||
ff451961 SRRH |
479 | mutex_lock(&trace_types_lock); |
480 | __trace_array_put(this_tr); | |
481 | mutex_unlock(&trace_types_lock); | |
482 | } | |
28879787 | 483 | EXPORT_SYMBOL_GPL(trace_array_put); |
ff451961 | 484 | |
8530dec6 SRV |
485 | int tracing_check_open_get_tr(struct trace_array *tr) |
486 | { | |
17911ff3 SRV |
487 | int ret; |
488 | ||
489 | ret = security_locked_down(LOCKDOWN_TRACEFS); | |
490 | if (ret) | |
491 | return ret; | |
492 | ||
8530dec6 SRV |
493 | if (tracing_disabled) |
494 | return -ENODEV; | |
495 | ||
496 | if (tr && trace_array_get(tr) < 0) | |
497 | return -ENODEV; | |
498 | ||
499 | return 0; | |
500 | } | |
501 | ||
2425bcb9 | 502 | int call_filter_check_discard(struct trace_event_call *call, void *rec, |
13292494 | 503 | struct trace_buffer *buffer, |
f306cc82 TZ |
504 | struct ring_buffer_event *event) |
505 | { | |
506 | if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && | |
507 | !filter_match_preds(call->filter, rec)) { | |
0fc1b09f | 508 | __trace_event_discard_commit(buffer, event); |
f306cc82 TZ |
509 | return 1; |
510 | } | |
511 | ||
512 | return 0; | |
eb02ce01 TZ |
513 | } |
514 | ||
76c813e2 SRRH |
515 | void trace_free_pid_list(struct trace_pid_list *pid_list) |
516 | { | |
517 | vfree(pid_list->pids); | |
518 | kfree(pid_list); | |
519 | } | |
520 | ||
d8275c45 SR |
521 | /** |
522 | * trace_find_filtered_pid - check if a pid exists in a filtered_pid list | |
523 | * @filtered_pids: The list of pids to check | |
524 | * @search_pid: The PID to find in @filtered_pids | |
525 | * | |
f2cc020d | 526 | * Returns true if @search_pid is found in @filtered_pids, and false otherwise. |
d8275c45 SR |
527 | */ |
528 | bool | |
529 | trace_find_filtered_pid(struct trace_pid_list *filtered_pids, pid_t search_pid) | |
530 | { | |
531 | /* | |
532 | * If pid_max changed after filtered_pids was created, we | |
533 | * by default ignore all pids greater than the previous pid_max. | |
534 | */ | |
535 | if (search_pid >= filtered_pids->pid_max) | |
536 | return false; | |
537 | ||
538 | return test_bit(search_pid, filtered_pids->pids); | |
539 | } | |
540 | ||
541 | /** | |
542 | * trace_ignore_this_task - should a task be ignored for tracing | |
543 | * @filtered_pids: The list of pids to check | |
b3ca59f6 | 544 | * @filtered_no_pids: The list of pids not to be traced |
d8275c45 SR |
545 | * @task: The task that should be ignored if not filtered |
546 | * | |
547 | * Checks if @task should be traced or not from @filtered_pids. | |
548 | * Returns true if @task should *NOT* be traced. | |
549 | * Returns false if @task should be traced. | |
550 | */ | |
551 | bool | |
b3b1e6ed SRV |
552 | trace_ignore_this_task(struct trace_pid_list *filtered_pids, |
553 | struct trace_pid_list *filtered_no_pids, | |
554 | struct task_struct *task) | |
d8275c45 SR |
555 | { |
556 | /* | |
f2cc020d | 557 | * If filtered_no_pids is not empty, and the task's pid is listed |
b3b1e6ed SRV |
558 | * in filtered_no_pids, then return true. |
559 | * Otherwise, if filtered_pids is empty, that means we can | |
560 | * trace all tasks. If it has content, then only trace pids | |
561 | * within filtered_pids. | |
d8275c45 | 562 | */ |
d8275c45 | 563 | |
b3b1e6ed SRV |
564 | return (filtered_pids && |
565 | !trace_find_filtered_pid(filtered_pids, task->pid)) || | |
566 | (filtered_no_pids && | |
567 | trace_find_filtered_pid(filtered_no_pids, task->pid)); | |
d8275c45 SR |
568 | } |
569 | ||
570 | /** | |
f08367b3 | 571 | * trace_filter_add_remove_task - Add or remove a task from a pid_list |
d8275c45 SR |
572 | * @pid_list: The list to modify |
573 | * @self: The current task for fork or NULL for exit | |
574 | * @task: The task to add or remove | |
575 | * | |
576 | * If adding a task, if @self is defined, the task is only added if @self | |
577 | * is also included in @pid_list. This happens on fork and tasks should | |
578 | * only be added when the parent is listed. If @self is NULL, then the | |
579 | * @task pid will be removed from the list, which would happen on exit | |
580 | * of a task. | |
581 | */ | |
582 | void trace_filter_add_remove_task(struct trace_pid_list *pid_list, | |
583 | struct task_struct *self, | |
584 | struct task_struct *task) | |
585 | { | |
586 | if (!pid_list) | |
587 | return; | |
588 | ||
589 | /* For forks, we only add if the forking task is listed */ | |
590 | if (self) { | |
591 | if (!trace_find_filtered_pid(pid_list, self->pid)) | |
592 | return; | |
593 | } | |
594 | ||
595 | /* Sorry, but we don't support pid_max changing after setting */ | |
596 | if (task->pid >= pid_list->pid_max) | |
597 | return; | |
598 | ||
599 | /* "self" is set for forks, and NULL for exits */ | |
600 | if (self) | |
601 | set_bit(task->pid, pid_list->pids); | |
602 | else | |
603 | clear_bit(task->pid, pid_list->pids); | |
604 | } | |
605 | ||
5cc8976b SRRH |
606 | /** |
607 | * trace_pid_next - Used for seq_file to get to the next pid of a pid_list | |
608 | * @pid_list: The pid list to show | |
609 | * @v: The last pid that was shown (+1 the actual pid to let zero be displayed) | |
610 | * @pos: The position of the file | |
611 | * | |
612 | * This is used by the seq_file "next" operation to iterate the pids | |
613 | * listed in a trace_pid_list structure. | |
614 | * | |
615 | * Returns the pid+1 as we want to display pid of zero, but NULL would | |
616 | * stop the iteration. | |
617 | */ | |
618 | void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos) | |
619 | { | |
620 | unsigned long pid = (unsigned long)v; | |
621 | ||
622 | (*pos)++; | |
623 | ||
f2cc020d | 624 | /* pid already is +1 of the actual previous bit */ |
5cc8976b SRRH |
625 | pid = find_next_bit(pid_list->pids, pid_list->pid_max, pid); |
626 | ||
627 | /* Return pid + 1 to allow zero to be represented */ | |
628 | if (pid < pid_list->pid_max) | |
629 | return (void *)(pid + 1); | |
630 | ||
631 | return NULL; | |
632 | } | |
633 | ||
634 | /** | |
635 | * trace_pid_start - Used for seq_file to start reading pid lists | |
636 | * @pid_list: The pid list to show | |
637 | * @pos: The position of the file | |
638 | * | |
639 | * This is used by seq_file "start" operation to start the iteration | |
640 | * of listing pids. | |
641 | * | |
642 | * Returns the pid+1 as we want to display pid of zero, but NULL would | |
643 | * stop the iteration. | |
644 | */ | |
645 | void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos) | |
646 | { | |
647 | unsigned long pid; | |
648 | loff_t l = 0; | |
649 | ||
650 | pid = find_first_bit(pid_list->pids, pid_list->pid_max); | |
651 | if (pid >= pid_list->pid_max) | |
652 | return NULL; | |
653 | ||
654 | /* Return pid + 1 so that zero can be the exit value */ | |
655 | for (pid++; pid && l < *pos; | |
656 | pid = (unsigned long)trace_pid_next(pid_list, (void *)pid, &l)) | |
657 | ; | |
658 | return (void *)pid; | |
659 | } | |
660 | ||
661 | /** | |
662 | * trace_pid_show - show the current pid in seq_file processing | |
663 | * @m: The seq_file structure to write into | |
664 | * @v: A void pointer of the pid (+1) value to display | |
665 | * | |
666 | * Can be directly used by seq_file operations to display the current | |
667 | * pid value. | |
668 | */ | |
669 | int trace_pid_show(struct seq_file *m, void *v) | |
670 | { | |
671 | unsigned long pid = (unsigned long)v - 1; | |
672 | ||
673 | seq_printf(m, "%lu\n", pid); | |
674 | return 0; | |
675 | } | |
676 | ||
76c813e2 SRRH |
677 | /* 128 should be much more than enough */ |
678 | #define PID_BUF_SIZE 127 | |
679 | ||
680 | int trace_pid_write(struct trace_pid_list *filtered_pids, | |
681 | struct trace_pid_list **new_pid_list, | |
682 | const char __user *ubuf, size_t cnt) | |
683 | { | |
684 | struct trace_pid_list *pid_list; | |
685 | struct trace_parser parser; | |
686 | unsigned long val; | |
687 | int nr_pids = 0; | |
688 | ssize_t read = 0; | |
689 | ssize_t ret = 0; | |
690 | loff_t pos; | |
691 | pid_t pid; | |
692 | ||
693 | if (trace_parser_get_init(&parser, PID_BUF_SIZE + 1)) | |
694 | return -ENOMEM; | |
695 | ||
696 | /* | |
697 | * Always recreate a new array. The write is an all or nothing | |
698 | * operation. Always create a new array when adding new pids by | |
699 | * the user. If the operation fails, then the current list is | |
700 | * not modified. | |
701 | */ | |
702 | pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL); | |
91862cc7 WW |
703 | if (!pid_list) { |
704 | trace_parser_put(&parser); | |
76c813e2 | 705 | return -ENOMEM; |
91862cc7 | 706 | } |
76c813e2 SRRH |
707 | |
708 | pid_list->pid_max = READ_ONCE(pid_max); | |
709 | ||
710 | /* Only truncating will shrink pid_max */ | |
711 | if (filtered_pids && filtered_pids->pid_max > pid_list->pid_max) | |
712 | pid_list->pid_max = filtered_pids->pid_max; | |
713 | ||
714 | pid_list->pids = vzalloc((pid_list->pid_max + 7) >> 3); | |
715 | if (!pid_list->pids) { | |
91862cc7 | 716 | trace_parser_put(&parser); |
76c813e2 SRRH |
717 | kfree(pid_list); |
718 | return -ENOMEM; | |
719 | } | |
720 | ||
721 | if (filtered_pids) { | |
722 | /* copy the current bits to the new max */ | |
67f20b08 WY |
723 | for_each_set_bit(pid, filtered_pids->pids, |
724 | filtered_pids->pid_max) { | |
76c813e2 | 725 | set_bit(pid, pid_list->pids); |
76c813e2 SRRH |
726 | nr_pids++; |
727 | } | |
728 | } | |
729 | ||
730 | while (cnt > 0) { | |
731 | ||
732 | pos = 0; | |
733 | ||
734 | ret = trace_get_user(&parser, ubuf, cnt, &pos); | |
735 | if (ret < 0 || !trace_parser_loaded(&parser)) | |
736 | break; | |
737 | ||
738 | read += ret; | |
739 | ubuf += ret; | |
740 | cnt -= ret; | |
741 | ||
76c813e2 SRRH |
742 | ret = -EINVAL; |
743 | if (kstrtoul(parser.buffer, 0, &val)) | |
744 | break; | |
745 | if (val >= pid_list->pid_max) | |
746 | break; | |
747 | ||
748 | pid = (pid_t)val; | |
749 | ||
750 | set_bit(pid, pid_list->pids); | |
751 | nr_pids++; | |
752 | ||
753 | trace_parser_clear(&parser); | |
754 | ret = 0; | |
755 | } | |
756 | trace_parser_put(&parser); | |
757 | ||
758 | if (ret < 0) { | |
759 | trace_free_pid_list(pid_list); | |
760 | return ret; | |
761 | } | |
762 | ||
763 | if (!nr_pids) { | |
764 | /* Cleared the list of pids */ | |
765 | trace_free_pid_list(pid_list); | |
766 | read = ret; | |
767 | pid_list = NULL; | |
768 | } | |
769 | ||
770 | *new_pid_list = pid_list; | |
771 | ||
772 | return read; | |
773 | } | |
774 | ||
1c5eb448 | 775 | static u64 buffer_ftrace_now(struct array_buffer *buf, int cpu) |
37886f6a SR |
776 | { |
777 | u64 ts; | |
778 | ||
779 | /* Early boot up does not have a buffer yet */ | |
9457158b | 780 | if (!buf->buffer) |
37886f6a SR |
781 | return trace_clock_local(); |
782 | ||
f3ef7202 | 783 | ts = ring_buffer_time_stamp(buf->buffer); |
9457158b | 784 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); |
37886f6a SR |
785 | |
786 | return ts; | |
787 | } | |
bc0c38d1 | 788 | |
a5a1d1c2 | 789 | u64 ftrace_now(int cpu) |
9457158b | 790 | { |
1c5eb448 | 791 | return buffer_ftrace_now(&global_trace.array_buffer, cpu); |
9457158b AL |
792 | } |
793 | ||
10246fa3 | 794 | /** |
b3ca59f6 | 795 | * tracing_is_enabled - Show if global_trace has been enabled |
10246fa3 SRRH |
796 | * |
797 | * Shows if the global trace has been enabled or not. It uses the | |
798 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
799 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
800 | * need to know the accurate state, use tracing_is_on() which is a little | |
801 | * slower, but accurate. | |
802 | */ | |
9036990d SR |
803 | int tracing_is_enabled(void) |
804 | { | |
10246fa3 SRRH |
805 | /* |
806 | * For quick access (irqsoff uses this in fast path), just | |
807 | * return the mirror variable of the state of the ring buffer. | |
808 | * It's a little racy, but we don't really care. | |
809 | */ | |
810 | smp_rmb(); | |
811 | return !global_trace.buffer_disabled; | |
9036990d SR |
812 | } |
813 | ||
4fcdae83 | 814 | /* |
3928a8a2 SR |
815 | * trace_buf_size is the size in bytes that is allocated |
816 | * for a buffer. Note, the number of bytes is always rounded | |
817 | * to page size. | |
3f5a54e3 SR |
818 | * |
819 | * This number is purposely set to a low number of 16384. | |
820 | * If the dump on oops happens, it will be much appreciated | |
821 | * to not have to wait for all that output. Anyway this can be | |
822 | * boot time and run time configurable. | |
4fcdae83 | 823 | */ |
3928a8a2 | 824 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 825 | |
3928a8a2 | 826 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 827 | |
4fcdae83 | 828 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 829 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 830 | |
4fcdae83 SR |
831 | /* |
832 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 833 | */ |
a8227415 | 834 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 835 | |
7e53bd42 LJ |
836 | /* |
837 | * serialize the access of the ring buffer | |
838 | * | |
839 | * ring buffer serializes readers, but it is low level protection. | |
840 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
841 | * are not protected by ring buffer. | |
842 | * | |
843 | * The content of events may become garbage if we allow other process consumes | |
844 | * these events concurrently: | |
845 | * A) the page of the consumed events may become a normal page | |
f2cc020d | 846 | * (not reader page) in ring buffer, and this page will be rewritten |
7e53bd42 LJ |
847 | * by events producer. |
848 | * B) The page of the consumed events may become a page for splice_read, | |
849 | * and this page will be returned to system. | |
850 | * | |
851 | * These primitives allow multi process access to different cpu ring buffer | |
852 | * concurrently. | |
853 | * | |
854 | * These primitives don't distinguish read-only and read-consume access. | |
855 | * Multi read-only access are also serialized. | |
856 | */ | |
857 | ||
858 | #ifdef CONFIG_SMP | |
859 | static DECLARE_RWSEM(all_cpu_access_lock); | |
860 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
861 | ||
862 | static inline void trace_access_lock(int cpu) | |
863 | { | |
ae3b5093 | 864 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
865 | /* gain it for accessing the whole ring buffer. */ |
866 | down_write(&all_cpu_access_lock); | |
867 | } else { | |
868 | /* gain it for accessing a cpu ring buffer. */ | |
869 | ||
ae3b5093 | 870 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
871 | down_read(&all_cpu_access_lock); |
872 | ||
873 | /* Secondly block other access to this @cpu ring buffer. */ | |
874 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
875 | } | |
876 | } | |
877 | ||
878 | static inline void trace_access_unlock(int cpu) | |
879 | { | |
ae3b5093 | 880 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
881 | up_write(&all_cpu_access_lock); |
882 | } else { | |
883 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
884 | up_read(&all_cpu_access_lock); | |
885 | } | |
886 | } | |
887 | ||
888 | static inline void trace_access_lock_init(void) | |
889 | { | |
890 | int cpu; | |
891 | ||
892 | for_each_possible_cpu(cpu) | |
893 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
894 | } | |
895 | ||
896 | #else | |
897 | ||
898 | static DEFINE_MUTEX(access_lock); | |
899 | ||
900 | static inline void trace_access_lock(int cpu) | |
901 | { | |
902 | (void)cpu; | |
903 | mutex_lock(&access_lock); | |
904 | } | |
905 | ||
906 | static inline void trace_access_unlock(int cpu) | |
907 | { | |
908 | (void)cpu; | |
909 | mutex_unlock(&access_lock); | |
910 | } | |
911 | ||
912 | static inline void trace_access_lock_init(void) | |
913 | { | |
914 | } | |
915 | ||
916 | #endif | |
917 | ||
d78a4614 | 918 | #ifdef CONFIG_STACKTRACE |
13292494 | 919 | static void __ftrace_trace_stack(struct trace_buffer *buffer, |
36590c50 SAS |
920 | unsigned int trace_ctx, |
921 | int skip, struct pt_regs *regs); | |
2d34f489 | 922 | static inline void ftrace_trace_stack(struct trace_array *tr, |
13292494 | 923 | struct trace_buffer *buffer, |
36590c50 SAS |
924 | unsigned int trace_ctx, |
925 | int skip, struct pt_regs *regs); | |
ca475e83 | 926 | |
d78a4614 | 927 | #else |
13292494 | 928 | static inline void __ftrace_trace_stack(struct trace_buffer *buffer, |
36590c50 SAS |
929 | unsigned int trace_ctx, |
930 | int skip, struct pt_regs *regs) | |
d78a4614 SRRH |
931 | { |
932 | } | |
2d34f489 | 933 | static inline void ftrace_trace_stack(struct trace_array *tr, |
13292494 | 934 | struct trace_buffer *buffer, |
36590c50 SAS |
935 | unsigned long trace_ctx, |
936 | int skip, struct pt_regs *regs) | |
ca475e83 SRRH |
937 | { |
938 | } | |
939 | ||
d78a4614 SRRH |
940 | #endif |
941 | ||
3e9a8aad SRRH |
942 | static __always_inline void |
943 | trace_event_setup(struct ring_buffer_event *event, | |
36590c50 | 944 | int type, unsigned int trace_ctx) |
3e9a8aad SRRH |
945 | { |
946 | struct trace_entry *ent = ring_buffer_event_data(event); | |
947 | ||
36590c50 | 948 | tracing_generic_entry_update(ent, type, trace_ctx); |
3e9a8aad SRRH |
949 | } |
950 | ||
951 | static __always_inline struct ring_buffer_event * | |
13292494 | 952 | __trace_buffer_lock_reserve(struct trace_buffer *buffer, |
3e9a8aad SRRH |
953 | int type, |
954 | unsigned long len, | |
36590c50 | 955 | unsigned int trace_ctx) |
3e9a8aad SRRH |
956 | { |
957 | struct ring_buffer_event *event; | |
958 | ||
959 | event = ring_buffer_lock_reserve(buffer, len); | |
960 | if (event != NULL) | |
36590c50 | 961 | trace_event_setup(event, type, trace_ctx); |
3e9a8aad SRRH |
962 | |
963 | return event; | |
964 | } | |
965 | ||
2290f2c5 | 966 | void tracer_tracing_on(struct trace_array *tr) |
10246fa3 | 967 | { |
1c5eb448 SRV |
968 | if (tr->array_buffer.buffer) |
969 | ring_buffer_record_on(tr->array_buffer.buffer); | |
10246fa3 SRRH |
970 | /* |
971 | * This flag is looked at when buffers haven't been allocated | |
972 | * yet, or by some tracers (like irqsoff), that just want to | |
973 | * know if the ring buffer has been disabled, but it can handle | |
974 | * races of where it gets disabled but we still do a record. | |
975 | * As the check is in the fast path of the tracers, it is more | |
976 | * important to be fast than accurate. | |
977 | */ | |
978 | tr->buffer_disabled = 0; | |
979 | /* Make the flag seen by readers */ | |
980 | smp_wmb(); | |
981 | } | |
982 | ||
499e5470 SR |
983 | /** |
984 | * tracing_on - enable tracing buffers | |
985 | * | |
986 | * This function enables tracing buffers that may have been | |
987 | * disabled with tracing_off. | |
988 | */ | |
989 | void tracing_on(void) | |
990 | { | |
10246fa3 | 991 | tracer_tracing_on(&global_trace); |
499e5470 SR |
992 | } |
993 | EXPORT_SYMBOL_GPL(tracing_on); | |
994 | ||
52ffabe3 SRRH |
995 | |
996 | static __always_inline void | |
13292494 | 997 | __buffer_unlock_commit(struct trace_buffer *buffer, struct ring_buffer_event *event) |
52ffabe3 | 998 | { |
d914ba37 | 999 | __this_cpu_write(trace_taskinfo_save, true); |
52ffabe3 SRRH |
1000 | |
1001 | /* If this is the temp buffer, we need to commit fully */ | |
1002 | if (this_cpu_read(trace_buffered_event) == event) { | |
1003 | /* Length is in event->array[0] */ | |
1004 | ring_buffer_write(buffer, event->array[0], &event->array[1]); | |
1005 | /* Release the temp buffer */ | |
1006 | this_cpu_dec(trace_buffered_event_cnt); | |
1007 | } else | |
1008 | ring_buffer_unlock_commit(buffer, event); | |
1009 | } | |
1010 | ||
09ae7234 SRRH |
1011 | /** |
1012 | * __trace_puts - write a constant string into the trace buffer. | |
1013 | * @ip: The address of the caller | |
1014 | * @str: The constant string to write | |
1015 | * @size: The size of the string. | |
1016 | */ | |
1017 | int __trace_puts(unsigned long ip, const char *str, int size) | |
1018 | { | |
1019 | struct ring_buffer_event *event; | |
13292494 | 1020 | struct trace_buffer *buffer; |
09ae7234 | 1021 | struct print_entry *entry; |
36590c50 | 1022 | unsigned int trace_ctx; |
09ae7234 | 1023 | int alloc; |
8abfb872 | 1024 | |
983f938a | 1025 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
f0160a5a J |
1026 | return 0; |
1027 | ||
3132e107 SRRH |
1028 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
1029 | return 0; | |
1030 | ||
09ae7234 SRRH |
1031 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ |
1032 | ||
36590c50 | 1033 | trace_ctx = tracing_gen_ctx(); |
1c5eb448 | 1034 | buffer = global_trace.array_buffer.buffer; |
82d1b815 | 1035 | ring_buffer_nest_start(buffer); |
36590c50 SAS |
1036 | event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, |
1037 | trace_ctx); | |
82d1b815 SRV |
1038 | if (!event) { |
1039 | size = 0; | |
1040 | goto out; | |
1041 | } | |
09ae7234 SRRH |
1042 | |
1043 | entry = ring_buffer_event_data(event); | |
1044 | entry->ip = ip; | |
1045 | ||
1046 | memcpy(&entry->buf, str, size); | |
1047 | ||
1048 | /* Add a newline if necessary */ | |
1049 | if (entry->buf[size - 1] != '\n') { | |
1050 | entry->buf[size] = '\n'; | |
1051 | entry->buf[size + 1] = '\0'; | |
1052 | } else | |
1053 | entry->buf[size] = '\0'; | |
1054 | ||
1055 | __buffer_unlock_commit(buffer, event); | |
36590c50 | 1056 | ftrace_trace_stack(&global_trace, buffer, trace_ctx, 4, NULL); |
82d1b815 SRV |
1057 | out: |
1058 | ring_buffer_nest_end(buffer); | |
09ae7234 SRRH |
1059 | return size; |
1060 | } | |
1061 | EXPORT_SYMBOL_GPL(__trace_puts); | |
1062 | ||
1063 | /** | |
1064 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
1065 | * @ip: The address of the caller | |
1066 | * @str: The constant string to write to the buffer to | |
1067 | */ | |
1068 | int __trace_bputs(unsigned long ip, const char *str) | |
1069 | { | |
1070 | struct ring_buffer_event *event; | |
13292494 | 1071 | struct trace_buffer *buffer; |
09ae7234 | 1072 | struct bputs_entry *entry; |
36590c50 | 1073 | unsigned int trace_ctx; |
09ae7234 | 1074 | int size = sizeof(struct bputs_entry); |
82d1b815 | 1075 | int ret = 0; |
8abfb872 | 1076 | |
983f938a | 1077 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
f0160a5a J |
1078 | return 0; |
1079 | ||
3132e107 SRRH |
1080 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
1081 | return 0; | |
1082 | ||
36590c50 | 1083 | trace_ctx = tracing_gen_ctx(); |
1c5eb448 | 1084 | buffer = global_trace.array_buffer.buffer; |
82d1b815 SRV |
1085 | |
1086 | ring_buffer_nest_start(buffer); | |
3e9a8aad | 1087 | event = __trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, |
36590c50 | 1088 | trace_ctx); |
09ae7234 | 1089 | if (!event) |
82d1b815 | 1090 | goto out; |
09ae7234 SRRH |
1091 | |
1092 | entry = ring_buffer_event_data(event); | |
1093 | entry->ip = ip; | |
1094 | entry->str = str; | |
1095 | ||
1096 | __buffer_unlock_commit(buffer, event); | |
36590c50 | 1097 | ftrace_trace_stack(&global_trace, buffer, trace_ctx, 4, NULL); |
09ae7234 | 1098 | |
82d1b815 SRV |
1099 | ret = 1; |
1100 | out: | |
1101 | ring_buffer_nest_end(buffer); | |
1102 | return ret; | |
09ae7234 SRRH |
1103 | } |
1104 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
1105 | ||
ad909e21 | 1106 | #ifdef CONFIG_TRACER_SNAPSHOT |
192b7993 ZW |
1107 | static void tracing_snapshot_instance_cond(struct trace_array *tr, |
1108 | void *cond_data) | |
ad909e21 | 1109 | { |
ad909e21 SRRH |
1110 | struct tracer *tracer = tr->current_trace; |
1111 | unsigned long flags; | |
1112 | ||
1b22e382 SRRH |
1113 | if (in_nmi()) { |
1114 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
1115 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
1116 | return; | |
1117 | } | |
1118 | ||
ad909e21 | 1119 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
1120 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
1121 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
1122 | tracing_off(); |
1123 | return; | |
1124 | } | |
1125 | ||
1126 | /* Note, snapshot can not be used when the tracer uses it */ | |
1127 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
1128 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
1129 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
1130 | return; |
1131 | } | |
1132 | ||
1133 | local_irq_save(flags); | |
a35873a0 | 1134 | update_max_tr(tr, current, smp_processor_id(), cond_data); |
ad909e21 SRRH |
1135 | local_irq_restore(flags); |
1136 | } | |
cab50379 | 1137 | |
a35873a0 TZ |
1138 | void tracing_snapshot_instance(struct trace_array *tr) |
1139 | { | |
1140 | tracing_snapshot_instance_cond(tr, NULL); | |
1141 | } | |
1142 | ||
cab50379 | 1143 | /** |
5a93bae2 | 1144 | * tracing_snapshot - take a snapshot of the current buffer. |
cab50379 SRV |
1145 | * |
1146 | * This causes a swap between the snapshot buffer and the current live | |
1147 | * tracing buffer. You can use this to take snapshots of the live | |
1148 | * trace when some condition is triggered, but continue to trace. | |
1149 | * | |
1150 | * Note, make sure to allocate the snapshot with either | |
1151 | * a tracing_snapshot_alloc(), or by doing it manually | |
1152 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
1153 | * | |
1154 | * If the snapshot buffer is not allocated, it will stop tracing. | |
1155 | * Basically making a permanent snapshot. | |
1156 | */ | |
1157 | void tracing_snapshot(void) | |
1158 | { | |
1159 | struct trace_array *tr = &global_trace; | |
1160 | ||
1161 | tracing_snapshot_instance(tr); | |
1162 | } | |
1b22e382 | 1163 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 | 1164 | |
a35873a0 TZ |
1165 | /** |
1166 | * tracing_snapshot_cond - conditionally take a snapshot of the current buffer. | |
1167 | * @tr: The tracing instance to snapshot | |
1168 | * @cond_data: The data to be tested conditionally, and possibly saved | |
1169 | * | |
1170 | * This is the same as tracing_snapshot() except that the snapshot is | |
1171 | * conditional - the snapshot will only happen if the | |
1172 | * cond_snapshot.update() implementation receiving the cond_data | |
1173 | * returns true, which means that the trace array's cond_snapshot | |
1174 | * update() operation used the cond_data to determine whether the | |
1175 | * snapshot should be taken, and if it was, presumably saved it along | |
1176 | * with the snapshot. | |
1177 | */ | |
1178 | void tracing_snapshot_cond(struct trace_array *tr, void *cond_data) | |
1179 | { | |
1180 | tracing_snapshot_instance_cond(tr, cond_data); | |
1181 | } | |
1182 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond); | |
1183 | ||
1184 | /** | |
1185 | * tracing_snapshot_cond_data - get the user data associated with a snapshot | |
1186 | * @tr: The tracing instance | |
1187 | * | |
1188 | * When the user enables a conditional snapshot using | |
1189 | * tracing_snapshot_cond_enable(), the user-defined cond_data is saved | |
1190 | * with the snapshot. This accessor is used to retrieve it. | |
1191 | * | |
1192 | * Should not be called from cond_snapshot.update(), since it takes | |
1193 | * the tr->max_lock lock, which the code calling | |
1194 | * cond_snapshot.update() has already done. | |
1195 | * | |
1196 | * Returns the cond_data associated with the trace array's snapshot. | |
1197 | */ | |
1198 | void *tracing_cond_snapshot_data(struct trace_array *tr) | |
1199 | { | |
1200 | void *cond_data = NULL; | |
1201 | ||
1202 | arch_spin_lock(&tr->max_lock); | |
1203 | ||
1204 | if (tr->cond_snapshot) | |
1205 | cond_data = tr->cond_snapshot->cond_data; | |
1206 | ||
1207 | arch_spin_unlock(&tr->max_lock); | |
1208 | ||
1209 | return cond_data; | |
1210 | } | |
1211 | EXPORT_SYMBOL_GPL(tracing_cond_snapshot_data); | |
1212 | ||
1c5eb448 SRV |
1213 | static int resize_buffer_duplicate_size(struct array_buffer *trace_buf, |
1214 | struct array_buffer *size_buf, int cpu_id); | |
1215 | static void set_buffer_entries(struct array_buffer *buf, unsigned long val); | |
3209cff4 | 1216 | |
2824f503 | 1217 | int tracing_alloc_snapshot_instance(struct trace_array *tr) |
3209cff4 SRRH |
1218 | { |
1219 | int ret; | |
1220 | ||
1221 | if (!tr->allocated_snapshot) { | |
1222 | ||
1223 | /* allocate spare buffer */ | |
1224 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
1c5eb448 | 1225 | &tr->array_buffer, RING_BUFFER_ALL_CPUS); |
3209cff4 SRRH |
1226 | if (ret < 0) |
1227 | return ret; | |
1228 | ||
1229 | tr->allocated_snapshot = true; | |
1230 | } | |
1231 | ||
1232 | return 0; | |
1233 | } | |
1234 | ||
ad1438a0 | 1235 | static void free_snapshot(struct trace_array *tr) |
3209cff4 SRRH |
1236 | { |
1237 | /* | |
1238 | * We don't free the ring buffer. instead, resize it because | |
1239 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
1240 | * we want preserve it. | |
1241 | */ | |
1242 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
1243 | set_buffer_entries(&tr->max_buffer, 1); | |
1244 | tracing_reset_online_cpus(&tr->max_buffer); | |
1245 | tr->allocated_snapshot = false; | |
1246 | } | |
ad909e21 | 1247 | |
93e31ffb TZ |
1248 | /** |
1249 | * tracing_alloc_snapshot - allocate snapshot buffer. | |
1250 | * | |
1251 | * This only allocates the snapshot buffer if it isn't already | |
1252 | * allocated - it doesn't also take a snapshot. | |
1253 | * | |
1254 | * This is meant to be used in cases where the snapshot buffer needs | |
1255 | * to be set up for events that can't sleep but need to be able to | |
1256 | * trigger a snapshot. | |
1257 | */ | |
1258 | int tracing_alloc_snapshot(void) | |
1259 | { | |
1260 | struct trace_array *tr = &global_trace; | |
1261 | int ret; | |
1262 | ||
2824f503 | 1263 | ret = tracing_alloc_snapshot_instance(tr); |
93e31ffb TZ |
1264 | WARN_ON(ret < 0); |
1265 | ||
1266 | return ret; | |
1267 | } | |
1268 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
1269 | ||
ad909e21 | 1270 | /** |
5a93bae2 | 1271 | * tracing_snapshot_alloc - allocate and take a snapshot of the current buffer. |
ad909e21 | 1272 | * |
5a93bae2 | 1273 | * This is similar to tracing_snapshot(), but it will allocate the |
ad909e21 SRRH |
1274 | * snapshot buffer if it isn't already allocated. Use this only |
1275 | * where it is safe to sleep, as the allocation may sleep. | |
1276 | * | |
1277 | * This causes a swap between the snapshot buffer and the current live | |
1278 | * tracing buffer. You can use this to take snapshots of the live | |
1279 | * trace when some condition is triggered, but continue to trace. | |
1280 | */ | |
1281 | void tracing_snapshot_alloc(void) | |
1282 | { | |
ad909e21 SRRH |
1283 | int ret; |
1284 | ||
93e31ffb TZ |
1285 | ret = tracing_alloc_snapshot(); |
1286 | if (ret < 0) | |
3209cff4 | 1287 | return; |
ad909e21 SRRH |
1288 | |
1289 | tracing_snapshot(); | |
1290 | } | |
1b22e382 | 1291 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
a35873a0 TZ |
1292 | |
1293 | /** | |
1294 | * tracing_snapshot_cond_enable - enable conditional snapshot for an instance | |
1295 | * @tr: The tracing instance | |
1296 | * @cond_data: User data to associate with the snapshot | |
1297 | * @update: Implementation of the cond_snapshot update function | |
1298 | * | |
1299 | * Check whether the conditional snapshot for the given instance has | |
1300 | * already been enabled, or if the current tracer is already using a | |
1301 | * snapshot; if so, return -EBUSY, else create a cond_snapshot and | |
1302 | * save the cond_data and update function inside. | |
1303 | * | |
1304 | * Returns 0 if successful, error otherwise. | |
1305 | */ | |
1306 | int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, | |
1307 | cond_update_fn_t update) | |
1308 | { | |
1309 | struct cond_snapshot *cond_snapshot; | |
1310 | int ret = 0; | |
1311 | ||
1312 | cond_snapshot = kzalloc(sizeof(*cond_snapshot), GFP_KERNEL); | |
1313 | if (!cond_snapshot) | |
1314 | return -ENOMEM; | |
1315 | ||
1316 | cond_snapshot->cond_data = cond_data; | |
1317 | cond_snapshot->update = update; | |
1318 | ||
1319 | mutex_lock(&trace_types_lock); | |
1320 | ||
1321 | ret = tracing_alloc_snapshot_instance(tr); | |
1322 | if (ret) | |
1323 | goto fail_unlock; | |
1324 | ||
1325 | if (tr->current_trace->use_max_tr) { | |
1326 | ret = -EBUSY; | |
1327 | goto fail_unlock; | |
1328 | } | |
1329 | ||
1c347a94 SRV |
1330 | /* |
1331 | * The cond_snapshot can only change to NULL without the | |
1332 | * trace_types_lock. We don't care if we race with it going | |
1333 | * to NULL, but we want to make sure that it's not set to | |
1334 | * something other than NULL when we get here, which we can | |
1335 | * do safely with only holding the trace_types_lock and not | |
1336 | * having to take the max_lock. | |
1337 | */ | |
a35873a0 TZ |
1338 | if (tr->cond_snapshot) { |
1339 | ret = -EBUSY; | |
1340 | goto fail_unlock; | |
1341 | } | |
1342 | ||
1343 | arch_spin_lock(&tr->max_lock); | |
1344 | tr->cond_snapshot = cond_snapshot; | |
1345 | arch_spin_unlock(&tr->max_lock); | |
1346 | ||
1347 | mutex_unlock(&trace_types_lock); | |
1348 | ||
1349 | return ret; | |
1350 | ||
1351 | fail_unlock: | |
1352 | mutex_unlock(&trace_types_lock); | |
1353 | kfree(cond_snapshot); | |
1354 | return ret; | |
1355 | } | |
1356 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond_enable); | |
1357 | ||
1358 | /** | |
1359 | * tracing_snapshot_cond_disable - disable conditional snapshot for an instance | |
1360 | * @tr: The tracing instance | |
1361 | * | |
1362 | * Check whether the conditional snapshot for the given instance is | |
1363 | * enabled; if so, free the cond_snapshot associated with it, | |
1364 | * otherwise return -EINVAL. | |
1365 | * | |
1366 | * Returns 0 if successful, error otherwise. | |
1367 | */ | |
1368 | int tracing_snapshot_cond_disable(struct trace_array *tr) | |
1369 | { | |
1370 | int ret = 0; | |
1371 | ||
1372 | arch_spin_lock(&tr->max_lock); | |
1373 | ||
1374 | if (!tr->cond_snapshot) | |
1375 | ret = -EINVAL; | |
1376 | else { | |
1377 | kfree(tr->cond_snapshot); | |
1378 | tr->cond_snapshot = NULL; | |
1379 | } | |
1380 | ||
1381 | arch_spin_unlock(&tr->max_lock); | |
1382 | ||
1383 | return ret; | |
1384 | } | |
1385 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond_disable); | |
ad909e21 SRRH |
1386 | #else |
1387 | void tracing_snapshot(void) | |
1388 | { | |
1389 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
1390 | } | |
1b22e382 | 1391 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
a35873a0 TZ |
1392 | void tracing_snapshot_cond(struct trace_array *tr, void *cond_data) |
1393 | { | |
1394 | WARN_ONCE(1, "Snapshot feature not enabled, but internal conditional snapshot used"); | |
1395 | } | |
1396 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond); | |
93e31ffb TZ |
1397 | int tracing_alloc_snapshot(void) |
1398 | { | |
1399 | WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); | |
1400 | return -ENODEV; | |
1401 | } | |
1402 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
ad909e21 SRRH |
1403 | void tracing_snapshot_alloc(void) |
1404 | { | |
1405 | /* Give warning */ | |
1406 | tracing_snapshot(); | |
1407 | } | |
1b22e382 | 1408 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
a35873a0 TZ |
1409 | void *tracing_cond_snapshot_data(struct trace_array *tr) |
1410 | { | |
1411 | return NULL; | |
1412 | } | |
1413 | EXPORT_SYMBOL_GPL(tracing_cond_snapshot_data); | |
1414 | int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update) | |
1415 | { | |
1416 | return -ENODEV; | |
1417 | } | |
1418 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond_enable); | |
1419 | int tracing_snapshot_cond_disable(struct trace_array *tr) | |
1420 | { | |
1421 | return false; | |
1422 | } | |
1423 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond_disable); | |
ad909e21 SRRH |
1424 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
1425 | ||
2290f2c5 | 1426 | void tracer_tracing_off(struct trace_array *tr) |
10246fa3 | 1427 | { |
1c5eb448 SRV |
1428 | if (tr->array_buffer.buffer) |
1429 | ring_buffer_record_off(tr->array_buffer.buffer); | |
10246fa3 SRRH |
1430 | /* |
1431 | * This flag is looked at when buffers haven't been allocated | |
1432 | * yet, or by some tracers (like irqsoff), that just want to | |
1433 | * know if the ring buffer has been disabled, but it can handle | |
1434 | * races of where it gets disabled but we still do a record. | |
1435 | * As the check is in the fast path of the tracers, it is more | |
1436 | * important to be fast than accurate. | |
1437 | */ | |
1438 | tr->buffer_disabled = 1; | |
1439 | /* Make the flag seen by readers */ | |
1440 | smp_wmb(); | |
1441 | } | |
1442 | ||
499e5470 SR |
1443 | /** |
1444 | * tracing_off - turn off tracing buffers | |
1445 | * | |
1446 | * This function stops the tracing buffers from recording data. | |
1447 | * It does not disable any overhead the tracers themselves may | |
1448 | * be causing. This function simply causes all recording to | |
1449 | * the ring buffers to fail. | |
1450 | */ | |
1451 | void tracing_off(void) | |
1452 | { | |
10246fa3 | 1453 | tracer_tracing_off(&global_trace); |
499e5470 SR |
1454 | } |
1455 | EXPORT_SYMBOL_GPL(tracing_off); | |
1456 | ||
de7edd31 SRRH |
1457 | void disable_trace_on_warning(void) |
1458 | { | |
c200784a SRV |
1459 | if (__disable_trace_on_warning) { |
1460 | trace_array_printk_buf(global_trace.array_buffer.buffer, _THIS_IP_, | |
1461 | "Disabling tracing due to warning\n"); | |
de7edd31 | 1462 | tracing_off(); |
c200784a | 1463 | } |
de7edd31 SRRH |
1464 | } |
1465 | ||
10246fa3 SRRH |
1466 | /** |
1467 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
1468 | * @tr : the trace array to know if ring buffer is enabled | |
1469 | * | |
1470 | * Shows real state of the ring buffer if it is enabled or not. | |
1471 | */ | |
ec573508 | 1472 | bool tracer_tracing_is_on(struct trace_array *tr) |
10246fa3 | 1473 | { |
1c5eb448 SRV |
1474 | if (tr->array_buffer.buffer) |
1475 | return ring_buffer_record_is_on(tr->array_buffer.buffer); | |
10246fa3 SRRH |
1476 | return !tr->buffer_disabled; |
1477 | } | |
1478 | ||
499e5470 SR |
1479 | /** |
1480 | * tracing_is_on - show state of ring buffers enabled | |
1481 | */ | |
1482 | int tracing_is_on(void) | |
1483 | { | |
10246fa3 | 1484 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
1485 | } |
1486 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
1487 | ||
3928a8a2 | 1488 | static int __init set_buf_size(char *str) |
bc0c38d1 | 1489 | { |
3928a8a2 | 1490 | unsigned long buf_size; |
c6caeeb1 | 1491 | |
bc0c38d1 SR |
1492 | if (!str) |
1493 | return 0; | |
9d612bef | 1494 | buf_size = memparse(str, &str); |
c6caeeb1 | 1495 | /* nr_entries can not be zero */ |
9d612bef | 1496 | if (buf_size == 0) |
c6caeeb1 | 1497 | return 0; |
3928a8a2 | 1498 | trace_buf_size = buf_size; |
bc0c38d1 SR |
1499 | return 1; |
1500 | } | |
3928a8a2 | 1501 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 1502 | |
0e950173 TB |
1503 | static int __init set_tracing_thresh(char *str) |
1504 | { | |
87abb3b1 | 1505 | unsigned long threshold; |
0e950173 TB |
1506 | int ret; |
1507 | ||
1508 | if (!str) | |
1509 | return 0; | |
bcd83ea6 | 1510 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
1511 | if (ret < 0) |
1512 | return 0; | |
87abb3b1 | 1513 | tracing_thresh = threshold * 1000; |
0e950173 TB |
1514 | return 1; |
1515 | } | |
1516 | __setup("tracing_thresh=", set_tracing_thresh); | |
1517 | ||
57f50be1 SR |
1518 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
1519 | { | |
1520 | return nsecs / 1000; | |
1521 | } | |
1522 | ||
a3418a36 SRRH |
1523 | /* |
1524 | * TRACE_FLAGS is defined as a tuple matching bit masks with strings. | |
f57a4143 | 1525 | * It uses C(a, b) where 'a' is the eval (enum) name and 'b' is the string that |
a3418a36 | 1526 | * matches it. By defining "C(a, b) b", TRACE_FLAGS becomes a list |
f57a4143 | 1527 | * of strings in the order that the evals (enum) were defined. |
a3418a36 SRRH |
1528 | */ |
1529 | #undef C | |
1530 | #define C(a, b) b | |
1531 | ||
f2cc020d | 1532 | /* These must match the bit positions in trace_iterator_flags */ |
bc0c38d1 | 1533 | static const char *trace_options[] = { |
a3418a36 | 1534 | TRACE_FLAGS |
bc0c38d1 SR |
1535 | NULL |
1536 | }; | |
1537 | ||
5079f326 Z |
1538 | static struct { |
1539 | u64 (*func)(void); | |
1540 | const char *name; | |
8be0709f | 1541 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 1542 | } trace_clocks[] = { |
1b3e5c09 TG |
1543 | { trace_clock_local, "local", 1 }, |
1544 | { trace_clock_global, "global", 1 }, | |
1545 | { trace_clock_counter, "counter", 0 }, | |
e7fda6c4 | 1546 | { trace_clock_jiffies, "uptime", 0 }, |
1b3e5c09 TG |
1547 | { trace_clock, "perf", 1 }, |
1548 | { ktime_get_mono_fast_ns, "mono", 1 }, | |
aabfa5f2 | 1549 | { ktime_get_raw_fast_ns, "mono_raw", 1 }, |
a3ed0e43 | 1550 | { ktime_get_boot_fast_ns, "boot", 1 }, |
8cbd9cc6 | 1551 | ARCH_TRACE_CLOCKS |
5079f326 Z |
1552 | }; |
1553 | ||
860f9f6b TZ |
1554 | bool trace_clock_in_ns(struct trace_array *tr) |
1555 | { | |
1556 | if (trace_clocks[tr->clock_id].in_ns) | |
1557 | return true; | |
1558 | ||
1559 | return false; | |
1560 | } | |
1561 | ||
b63f39ea | 1562 | /* |
1563 | * trace_parser_get_init - gets the buffer for trace parser | |
1564 | */ | |
1565 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
1566 | { | |
1567 | memset(parser, 0, sizeof(*parser)); | |
1568 | ||
1569 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
1570 | if (!parser->buffer) | |
1571 | return 1; | |
1572 | ||
1573 | parser->size = size; | |
1574 | return 0; | |
1575 | } | |
1576 | ||
1577 | /* | |
1578 | * trace_parser_put - frees the buffer for trace parser | |
1579 | */ | |
1580 | void trace_parser_put(struct trace_parser *parser) | |
1581 | { | |
1582 | kfree(parser->buffer); | |
0e684b65 | 1583 | parser->buffer = NULL; |
b63f39ea | 1584 | } |
1585 | ||
1586 | /* | |
1587 | * trace_get_user - reads the user input string separated by space | |
1588 | * (matched by isspace(ch)) | |
1589 | * | |
1590 | * For each string found the 'struct trace_parser' is updated, | |
1591 | * and the function returns. | |
1592 | * | |
1593 | * Returns number of bytes read. | |
1594 | * | |
1595 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
1596 | */ | |
1597 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
1598 | size_t cnt, loff_t *ppos) | |
1599 | { | |
1600 | char ch; | |
1601 | size_t read = 0; | |
1602 | ssize_t ret; | |
1603 | ||
1604 | if (!*ppos) | |
1605 | trace_parser_clear(parser); | |
1606 | ||
1607 | ret = get_user(ch, ubuf++); | |
1608 | if (ret) | |
1609 | goto out; | |
1610 | ||
1611 | read++; | |
1612 | cnt--; | |
1613 | ||
1614 | /* | |
1615 | * The parser is not finished with the last write, | |
1616 | * continue reading the user input without skipping spaces. | |
1617 | */ | |
1618 | if (!parser->cont) { | |
1619 | /* skip white space */ | |
1620 | while (cnt && isspace(ch)) { | |
1621 | ret = get_user(ch, ubuf++); | |
1622 | if (ret) | |
1623 | goto out; | |
1624 | read++; | |
1625 | cnt--; | |
1626 | } | |
1627 | ||
76638d96 CD |
1628 | parser->idx = 0; |
1629 | ||
b63f39ea | 1630 | /* only spaces were written */ |
921a7acd | 1631 | if (isspace(ch) || !ch) { |
b63f39ea | 1632 | *ppos += read; |
1633 | ret = read; | |
1634 | goto out; | |
1635 | } | |
b63f39ea | 1636 | } |
1637 | ||
1638 | /* read the non-space input */ | |
921a7acd | 1639 | while (cnt && !isspace(ch) && ch) { |
3c235a33 | 1640 | if (parser->idx < parser->size - 1) |
b63f39ea | 1641 | parser->buffer[parser->idx++] = ch; |
1642 | else { | |
1643 | ret = -EINVAL; | |
1644 | goto out; | |
1645 | } | |
1646 | ret = get_user(ch, ubuf++); | |
1647 | if (ret) | |
1648 | goto out; | |
1649 | read++; | |
1650 | cnt--; | |
1651 | } | |
1652 | ||
1653 | /* We either got finished input or we have to wait for another call. */ | |
921a7acd | 1654 | if (isspace(ch) || !ch) { |
b63f39ea | 1655 | parser->buffer[parser->idx] = 0; |
1656 | parser->cont = false; | |
057db848 | 1657 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 1658 | parser->cont = true; |
1659 | parser->buffer[parser->idx++] = ch; | |
f4d0706c CD |
1660 | /* Make sure the parsed string always terminates with '\0'. */ |
1661 | parser->buffer[parser->idx] = 0; | |
057db848 SR |
1662 | } else { |
1663 | ret = -EINVAL; | |
1664 | goto out; | |
b63f39ea | 1665 | } |
1666 | ||
1667 | *ppos += read; | |
1668 | ret = read; | |
1669 | ||
1670 | out: | |
1671 | return ret; | |
1672 | } | |
1673 | ||
3a161d99 | 1674 | /* TODO add a seq_buf_to_buffer() */ |
b8b94265 | 1675 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
1676 | { |
1677 | int len; | |
3c56819b | 1678 | |
5ac48378 | 1679 | if (trace_seq_used(s) <= s->seq.readpos) |
3c56819b EGM |
1680 | return -EBUSY; |
1681 | ||
5ac48378 | 1682 | len = trace_seq_used(s) - s->seq.readpos; |
3c56819b EGM |
1683 | if (cnt > len) |
1684 | cnt = len; | |
3a161d99 | 1685 | memcpy(buf, s->buffer + s->seq.readpos, cnt); |
3c56819b | 1686 | |
3a161d99 | 1687 | s->seq.readpos += cnt; |
3c56819b EGM |
1688 | return cnt; |
1689 | } | |
1690 | ||
0e950173 | 1691 | unsigned long __read_mostly tracing_thresh; |
91edde2e VRB |
1692 | static const struct file_operations tracing_max_lat_fops; |
1693 | ||
6880c987 | 1694 | #ifdef LATENCY_FS_NOTIFY |
91edde2e VRB |
1695 | |
1696 | static struct workqueue_struct *fsnotify_wq; | |
1697 | ||
1698 | static void latency_fsnotify_workfn(struct work_struct *work) | |
1699 | { | |
1700 | struct trace_array *tr = container_of(work, struct trace_array, | |
1701 | fsnotify_work); | |
82ace1ef | 1702 | fsnotify_inode(tr->d_max_latency->d_inode, FS_MODIFY); |
91edde2e VRB |
1703 | } |
1704 | ||
1705 | static void latency_fsnotify_workfn_irq(struct irq_work *iwork) | |
1706 | { | |
1707 | struct trace_array *tr = container_of(iwork, struct trace_array, | |
1708 | fsnotify_irqwork); | |
1709 | queue_work(fsnotify_wq, &tr->fsnotify_work); | |
1710 | } | |
1711 | ||
1712 | static void trace_create_maxlat_file(struct trace_array *tr, | |
1713 | struct dentry *d_tracer) | |
1714 | { | |
1715 | INIT_WORK(&tr->fsnotify_work, latency_fsnotify_workfn); | |
1716 | init_irq_work(&tr->fsnotify_irqwork, latency_fsnotify_workfn_irq); | |
bd324cfc SRV |
1717 | tr->d_max_latency = trace_create_file("tracing_max_latency", |
1718 | TRACE_MODE_WRITE, | |
91edde2e VRB |
1719 | d_tracer, &tr->max_latency, |
1720 | &tracing_max_lat_fops); | |
1721 | } | |
1722 | ||
1723 | __init static int latency_fsnotify_init(void) | |
1724 | { | |
1725 | fsnotify_wq = alloc_workqueue("tr_max_lat_wq", | |
1726 | WQ_UNBOUND | WQ_HIGHPRI, 0); | |
1727 | if (!fsnotify_wq) { | |
1728 | pr_err("Unable to allocate tr_max_lat_wq\n"); | |
1729 | return -ENOMEM; | |
1730 | } | |
1731 | return 0; | |
1732 | } | |
1733 | ||
1734 | late_initcall_sync(latency_fsnotify_init); | |
1735 | ||
1736 | void latency_fsnotify(struct trace_array *tr) | |
1737 | { | |
1738 | if (!fsnotify_wq) | |
1739 | return; | |
1740 | /* | |
1741 | * We cannot call queue_work(&tr->fsnotify_work) from here because it's | |
1742 | * possible that we are called from __schedule() or do_idle(), which | |
1743 | * could cause a deadlock. | |
1744 | */ | |
1745 | irq_work_queue(&tr->fsnotify_irqwork); | |
1746 | } | |
1747 | ||
424b650f JL |
1748 | #elif defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) \ |
1749 | || defined(CONFIG_OSNOISE_TRACER) | |
91edde2e VRB |
1750 | |
1751 | #define trace_create_maxlat_file(tr, d_tracer) \ | |
bd324cfc SRV |
1752 | trace_create_file("tracing_max_latency", TRACE_MODE_WRITE, \ |
1753 | d_tracer, &tr->max_latency, &tracing_max_lat_fops) | |
91edde2e | 1754 | |
424b650f JL |
1755 | #else |
1756 | #define trace_create_maxlat_file(tr, d_tracer) do { } while (0) | |
91edde2e | 1757 | #endif |
0e950173 | 1758 | |
5d4a9dba | 1759 | #ifdef CONFIG_TRACER_MAX_TRACE |
5d4a9dba SR |
1760 | /* |
1761 | * Copy the new maximum trace into the separate maximum-trace | |
1762 | * structure. (this way the maximum trace is permanently saved, | |
5a93bae2 | 1763 | * for later retrieval via /sys/kernel/tracing/tracing_max_latency) |
5d4a9dba SR |
1764 | */ |
1765 | static void | |
1766 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
1767 | { | |
1c5eb448 SRV |
1768 | struct array_buffer *trace_buf = &tr->array_buffer; |
1769 | struct array_buffer *max_buf = &tr->max_buffer; | |
12883efb SRRH |
1770 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); |
1771 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 1772 | |
12883efb SRRH |
1773 | max_buf->cpu = cpu; |
1774 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 1775 | |
6d9b3fa5 | 1776 | max_data->saved_latency = tr->max_latency; |
8248ac05 SR |
1777 | max_data->critical_start = data->critical_start; |
1778 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 1779 | |
85f726a3 | 1780 | strncpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 1781 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
1782 | /* |
1783 | * If tsk == current, then use current_uid(), as that does not use | |
1784 | * RCU. The irq tracer can be called out of RCU scope. | |
1785 | */ | |
1786 | if (tsk == current) | |
1787 | max_data->uid = current_uid(); | |
1788 | else | |
1789 | max_data->uid = task_uid(tsk); | |
1790 | ||
8248ac05 SR |
1791 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
1792 | max_data->policy = tsk->policy; | |
1793 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
1794 | |
1795 | /* record this tasks comm */ | |
1796 | tracing_record_cmdline(tsk); | |
91edde2e | 1797 | latency_fsnotify(tr); |
5d4a9dba SR |
1798 | } |
1799 | ||
4fcdae83 SR |
1800 | /** |
1801 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
1802 | * @tr: tracer | |
1803 | * @tsk: the task with the latency | |
1804 | * @cpu: The cpu that initiated the trace. | |
a35873a0 | 1805 | * @cond_data: User data associated with a conditional snapshot |
4fcdae83 SR |
1806 | * |
1807 | * Flip the buffers between the @tr and the max_tr and record information | |
1808 | * about which task was the cause of this latency. | |
1809 | */ | |
e309b41d | 1810 | void |
a35873a0 TZ |
1811 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu, |
1812 | void *cond_data) | |
bc0c38d1 | 1813 | { |
2b6080f2 | 1814 | if (tr->stop_count) |
b8de7bd1 SR |
1815 | return; |
1816 | ||
4c11d7ae | 1817 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 1818 | |
45ad21ca | 1819 | if (!tr->allocated_snapshot) { |
debdd57f | 1820 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 1821 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 1822 | return; |
debdd57f | 1823 | } |
34600f0e | 1824 | |
0b9b12c1 | 1825 | arch_spin_lock(&tr->max_lock); |
3928a8a2 | 1826 | |
1c5eb448 SRV |
1827 | /* Inherit the recordable setting from array_buffer */ |
1828 | if (ring_buffer_record_is_set_on(tr->array_buffer.buffer)) | |
73c8d894 MH |
1829 | ring_buffer_record_on(tr->max_buffer.buffer); |
1830 | else | |
1831 | ring_buffer_record_off(tr->max_buffer.buffer); | |
1832 | ||
a35873a0 TZ |
1833 | #ifdef CONFIG_TRACER_SNAPSHOT |
1834 | if (tr->cond_snapshot && !tr->cond_snapshot->update(tr, cond_data)) | |
1835 | goto out_unlock; | |
1836 | #endif | |
1c5eb448 | 1837 | swap(tr->array_buffer.buffer, tr->max_buffer.buffer); |
3928a8a2 | 1838 | |
bc0c38d1 | 1839 | __update_max_tr(tr, tsk, cpu); |
a35873a0 TZ |
1840 | |
1841 | out_unlock: | |
0b9b12c1 | 1842 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 SR |
1843 | } |
1844 | ||
1845 | /** | |
1846 | * update_max_tr_single - only copy one trace over, and reset the rest | |
c68c9ec1 JK |
1847 | * @tr: tracer |
1848 | * @tsk: task with the latency | |
1849 | * @cpu: the cpu of the buffer to copy. | |
4fcdae83 SR |
1850 | * |
1851 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1852 | */ |
e309b41d | 1853 | void |
bc0c38d1 SR |
1854 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1855 | { | |
3928a8a2 | 1856 | int ret; |
bc0c38d1 | 1857 | |
2b6080f2 | 1858 | if (tr->stop_count) |
b8de7bd1 SR |
1859 | return; |
1860 | ||
4c11d7ae | 1861 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1862 | if (!tr->allocated_snapshot) { |
2930e04d | 1863 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1864 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1865 | return; |
2930e04d | 1866 | } |
ef710e10 | 1867 | |
0b9b12c1 | 1868 | arch_spin_lock(&tr->max_lock); |
bc0c38d1 | 1869 | |
1c5eb448 | 1870 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->array_buffer.buffer, cpu); |
3928a8a2 | 1871 | |
e8165dbb SR |
1872 | if (ret == -EBUSY) { |
1873 | /* | |
1874 | * We failed to swap the buffer due to a commit taking | |
1875 | * place on this CPU. We fail to record, but we reset | |
1876 | * the max trace buffer (no one writes directly to it) | |
1877 | * and flag that it failed. | |
1878 | */ | |
12883efb | 1879 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1880 | "Failed to swap buffers due to commit in progress\n"); |
1881 | } | |
1882 | ||
e8165dbb | 1883 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1884 | |
1885 | __update_max_tr(tr, tsk, cpu); | |
0b9b12c1 | 1886 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 | 1887 | } |
5d4a9dba | 1888 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1889 | |
2c2b0a78 | 1890 | static int wait_on_pipe(struct trace_iterator *iter, int full) |
0d5c6e1c | 1891 | { |
15693458 SRRH |
1892 | /* Iterators are static, they should be filled or empty */ |
1893 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
8b8b3683 | 1894 | return 0; |
0d5c6e1c | 1895 | |
1c5eb448 | 1896 | return ring_buffer_wait(iter->array_buffer->buffer, iter->cpu_file, |
e30f53aa | 1897 | full); |
0d5c6e1c SR |
1898 | } |
1899 | ||
f4e781c0 | 1900 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
9afecfbb SRV |
1901 | static bool selftests_can_run; |
1902 | ||
1903 | struct trace_selftests { | |
1904 | struct list_head list; | |
1905 | struct tracer *type; | |
1906 | }; | |
1907 | ||
1908 | static LIST_HEAD(postponed_selftests); | |
1909 | ||
1910 | static int save_selftest(struct tracer *type) | |
1911 | { | |
1912 | struct trace_selftests *selftest; | |
1913 | ||
1914 | selftest = kmalloc(sizeof(*selftest), GFP_KERNEL); | |
1915 | if (!selftest) | |
1916 | return -ENOMEM; | |
1917 | ||
1918 | selftest->type = type; | |
1919 | list_add(&selftest->list, &postponed_selftests); | |
1920 | return 0; | |
1921 | } | |
1922 | ||
f4e781c0 SRRH |
1923 | static int run_tracer_selftest(struct tracer *type) |
1924 | { | |
1925 | struct trace_array *tr = &global_trace; | |
1926 | struct tracer *saved_tracer = tr->current_trace; | |
1927 | int ret; | |
0d5c6e1c | 1928 | |
f4e781c0 SRRH |
1929 | if (!type->selftest || tracing_selftest_disabled) |
1930 | return 0; | |
0d5c6e1c | 1931 | |
9afecfbb SRV |
1932 | /* |
1933 | * If a tracer registers early in boot up (before scheduling is | |
1934 | * initialized and such), then do not run its selftests yet. | |
1935 | * Instead, run it a little later in the boot process. | |
1936 | */ | |
1937 | if (!selftests_can_run) | |
1938 | return save_selftest(type); | |
1939 | ||
ee666a18 SRV |
1940 | if (!tracing_is_on()) { |
1941 | pr_warn("Selftest for tracer %s skipped due to tracing disabled\n", | |
1942 | type->name); | |
1943 | return 0; | |
1944 | } | |
1945 | ||
0d5c6e1c | 1946 | /* |
f4e781c0 SRRH |
1947 | * Run a selftest on this tracer. |
1948 | * Here we reset the trace buffer, and set the current | |
1949 | * tracer to be this tracer. The tracer can then run some | |
1950 | * internal tracing to verify that everything is in order. | |
1951 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1952 | */ |
1c5eb448 | 1953 | tracing_reset_online_cpus(&tr->array_buffer); |
0d5c6e1c | 1954 | |
f4e781c0 SRRH |
1955 | tr->current_trace = type; |
1956 | ||
1957 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1958 | if (type->use_max_tr) { | |
1959 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1960 | if (ring_buffer_expanded) | |
1961 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1962 | RING_BUFFER_ALL_CPUS); | |
1963 | tr->allocated_snapshot = true; | |
1964 | } | |
1965 | #endif | |
1966 | ||
1967 | /* the test is responsible for initializing and enabling */ | |
1968 | pr_info("Testing tracer %s: ", type->name); | |
1969 | ret = type->selftest(type, tr); | |
1970 | /* the test is responsible for resetting too */ | |
1971 | tr->current_trace = saved_tracer; | |
1972 | if (ret) { | |
1973 | printk(KERN_CONT "FAILED!\n"); | |
1974 | /* Add the warning after printing 'FAILED' */ | |
1975 | WARN_ON(1); | |
1976 | return -1; | |
1977 | } | |
1978 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1c5eb448 | 1979 | tracing_reset_online_cpus(&tr->array_buffer); |
f4e781c0 SRRH |
1980 | |
1981 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1982 | if (type->use_max_tr) { | |
1983 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1984 | |
f4e781c0 SRRH |
1985 | /* Shrink the max buffer again */ |
1986 | if (ring_buffer_expanded) | |
1987 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1988 | RING_BUFFER_ALL_CPUS); | |
1989 | } | |
1990 | #endif | |
1991 | ||
1992 | printk(KERN_CONT "PASSED\n"); | |
1993 | return 0; | |
1994 | } | |
9afecfbb SRV |
1995 | |
1996 | static __init int init_trace_selftests(void) | |
1997 | { | |
1998 | struct trace_selftests *p, *n; | |
1999 | struct tracer *t, **last; | |
2000 | int ret; | |
2001 | ||
2002 | selftests_can_run = true; | |
2003 | ||
2004 | mutex_lock(&trace_types_lock); | |
2005 | ||
2006 | if (list_empty(&postponed_selftests)) | |
2007 | goto out; | |
2008 | ||
2009 | pr_info("Running postponed tracer tests:\n"); | |
2010 | ||
78041c0c | 2011 | tracing_selftest_running = true; |
9afecfbb | 2012 | list_for_each_entry_safe(p, n, &postponed_selftests, list) { |
6fc2171c AR |
2013 | /* This loop can take minutes when sanitizers are enabled, so |
2014 | * lets make sure we allow RCU processing. | |
2015 | */ | |
2016 | cond_resched(); | |
9afecfbb SRV |
2017 | ret = run_tracer_selftest(p->type); |
2018 | /* If the test fails, then warn and remove from available_tracers */ | |
2019 | if (ret < 0) { | |
2020 | WARN(1, "tracer: %s failed selftest, disabling\n", | |
2021 | p->type->name); | |
2022 | last = &trace_types; | |
2023 | for (t = trace_types; t; t = t->next) { | |
2024 | if (t == p->type) { | |
2025 | *last = t->next; | |
2026 | break; | |
2027 | } | |
2028 | last = &t->next; | |
2029 | } | |
2030 | } | |
2031 | list_del(&p->list); | |
2032 | kfree(p); | |
2033 | } | |
78041c0c | 2034 | tracing_selftest_running = false; |
9afecfbb SRV |
2035 | |
2036 | out: | |
2037 | mutex_unlock(&trace_types_lock); | |
2038 | ||
2039 | return 0; | |
2040 | } | |
b9ef0326 | 2041 | core_initcall(init_trace_selftests); |
f4e781c0 SRRH |
2042 | #else |
2043 | static inline int run_tracer_selftest(struct tracer *type) | |
2044 | { | |
2045 | return 0; | |
0d5c6e1c | 2046 | } |
f4e781c0 | 2047 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 2048 | |
41d9c0be SRRH |
2049 | static void add_tracer_options(struct trace_array *tr, struct tracer *t); |
2050 | ||
a4d1e688 JW |
2051 | static void __init apply_trace_boot_options(void); |
2052 | ||
4fcdae83 SR |
2053 | /** |
2054 | * register_tracer - register a tracer with the ftrace system. | |
c68c9ec1 | 2055 | * @type: the plugin for the tracer |
4fcdae83 SR |
2056 | * |
2057 | * Register a new plugin tracer. | |
2058 | */ | |
a4d1e688 | 2059 | int __init register_tracer(struct tracer *type) |
bc0c38d1 SR |
2060 | { |
2061 | struct tracer *t; | |
bc0c38d1 SR |
2062 | int ret = 0; |
2063 | ||
2064 | if (!type->name) { | |
2065 | pr_info("Tracer must have a name\n"); | |
2066 | return -1; | |
2067 | } | |
2068 | ||
24a461d5 | 2069 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
2070 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
2071 | return -1; | |
2072 | } | |
2073 | ||
a356646a | 2074 | if (security_locked_down(LOCKDOWN_TRACEFS)) { |
ee195452 | 2075 | pr_warn("Can not register tracer %s due to lockdown\n", |
a356646a SRV |
2076 | type->name); |
2077 | return -EPERM; | |
2078 | } | |
2079 | ||
bc0c38d1 | 2080 | mutex_lock(&trace_types_lock); |
86fa2f60 | 2081 | |
8e1b82e0 FW |
2082 | tracing_selftest_running = true; |
2083 | ||
bc0c38d1 SR |
2084 | for (t = trace_types; t; t = t->next) { |
2085 | if (strcmp(type->name, t->name) == 0) { | |
2086 | /* already found */ | |
ee6c2c1b | 2087 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
2088 | type->name); |
2089 | ret = -1; | |
2090 | goto out; | |
2091 | } | |
2092 | } | |
2093 | ||
adf9f195 FW |
2094 | if (!type->set_flag) |
2095 | type->set_flag = &dummy_set_flag; | |
d39cdd20 CH |
2096 | if (!type->flags) { |
2097 | /*allocate a dummy tracer_flags*/ | |
2098 | type->flags = kmalloc(sizeof(*type->flags), GFP_KERNEL); | |
c8ca003b CH |
2099 | if (!type->flags) { |
2100 | ret = -ENOMEM; | |
2101 | goto out; | |
2102 | } | |
d39cdd20 CH |
2103 | type->flags->val = 0; |
2104 | type->flags->opts = dummy_tracer_opt; | |
2105 | } else | |
adf9f195 FW |
2106 | if (!type->flags->opts) |
2107 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 | 2108 | |
d39cdd20 CH |
2109 | /* store the tracer for __set_tracer_option */ |
2110 | type->flags->trace = type; | |
2111 | ||
f4e781c0 SRRH |
2112 | ret = run_tracer_selftest(type); |
2113 | if (ret < 0) | |
2114 | goto out; | |
60a11774 | 2115 | |
bc0c38d1 SR |
2116 | type->next = trace_types; |
2117 | trace_types = type; | |
41d9c0be | 2118 | add_tracer_options(&global_trace, type); |
60a11774 | 2119 | |
bc0c38d1 | 2120 | out: |
8e1b82e0 | 2121 | tracing_selftest_running = false; |
bc0c38d1 SR |
2122 | mutex_unlock(&trace_types_lock); |
2123 | ||
dac74940 SR |
2124 | if (ret || !default_bootup_tracer) |
2125 | goto out_unlock; | |
2126 | ||
ee6c2c1b | 2127 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
2128 | goto out_unlock; |
2129 | ||
2130 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
2131 | /* Do we want this tracer to start on bootup? */ | |
607e2ea1 | 2132 | tracing_set_tracer(&global_trace, type->name); |
dac74940 | 2133 | default_bootup_tracer = NULL; |
a4d1e688 JW |
2134 | |
2135 | apply_trace_boot_options(); | |
2136 | ||
dac74940 | 2137 | /* disable other selftests, since this will break it. */ |
60efe21e | 2138 | disable_tracing_selftest("running a tracer"); |
b2821ae6 | 2139 | |
dac74940 | 2140 | out_unlock: |
bc0c38d1 SR |
2141 | return ret; |
2142 | } | |
2143 | ||
1c5eb448 | 2144 | static void tracing_reset_cpu(struct array_buffer *buf, int cpu) |
f633903a | 2145 | { |
13292494 | 2146 | struct trace_buffer *buffer = buf->buffer; |
f633903a | 2147 | |
a5416411 HT |
2148 | if (!buffer) |
2149 | return; | |
2150 | ||
f633903a SR |
2151 | ring_buffer_record_disable(buffer); |
2152 | ||
2153 | /* Make sure all commits have finished */ | |
74401729 | 2154 | synchronize_rcu(); |
68179686 | 2155 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
2156 | |
2157 | ring_buffer_record_enable(buffer); | |
2158 | } | |
2159 | ||
1c5eb448 | 2160 | void tracing_reset_online_cpus(struct array_buffer *buf) |
213cc060 | 2161 | { |
13292494 | 2162 | struct trace_buffer *buffer = buf->buffer; |
213cc060 | 2163 | |
a5416411 HT |
2164 | if (!buffer) |
2165 | return; | |
2166 | ||
621968cd SR |
2167 | ring_buffer_record_disable(buffer); |
2168 | ||
2169 | /* Make sure all commits have finished */ | |
74401729 | 2170 | synchronize_rcu(); |
621968cd | 2171 | |
9457158b | 2172 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 | 2173 | |
b23d7a5f | 2174 | ring_buffer_reset_online_cpus(buffer); |
621968cd SR |
2175 | |
2176 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
2177 | } |
2178 | ||
09d8091c | 2179 | /* Must have trace_types_lock held */ |
873c642f | 2180 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 2181 | { |
873c642f SRRH |
2182 | struct trace_array *tr; |
2183 | ||
873c642f | 2184 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
065e63f9 SRV |
2185 | if (!tr->clear_trace) |
2186 | continue; | |
2187 | tr->clear_trace = false; | |
1c5eb448 | 2188 | tracing_reset_online_cpus(&tr->array_buffer); |
12883efb SRRH |
2189 | #ifdef CONFIG_TRACER_MAX_TRACE |
2190 | tracing_reset_online_cpus(&tr->max_buffer); | |
2191 | #endif | |
873c642f | 2192 | } |
9456f0fa SR |
2193 | } |
2194 | ||
4030a6e6 PB |
2195 | /* |
2196 | * The tgid_map array maps from pid to tgid; i.e. the value stored at index i | |
2197 | * is the tgid last observed corresponding to pid=i. | |
2198 | */ | |
d914ba37 JF |
2199 | static int *tgid_map; |
2200 | ||
4030a6e6 PB |
2201 | /* The maximum valid index into tgid_map. */ |
2202 | static size_t tgid_map_max; | |
2203 | ||
939c7a4f | 2204 | #define SAVED_CMDLINES_DEFAULT 128 |
2c7eea4c | 2205 | #define NO_CMDLINE_MAP UINT_MAX |
edc35bd7 | 2206 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
939c7a4f YY |
2207 | struct saved_cmdlines_buffer { |
2208 | unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
2209 | unsigned *map_cmdline_to_pid; | |
2210 | unsigned cmdline_num; | |
2211 | int cmdline_idx; | |
2212 | char *saved_cmdlines; | |
2213 | }; | |
2214 | static struct saved_cmdlines_buffer *savedcmd; | |
25b0b44a | 2215 | |
939c7a4f YY |
2216 | static inline char *get_saved_cmdlines(int idx) |
2217 | { | |
2218 | return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN]; | |
2219 | } | |
2220 | ||
2221 | static inline void set_cmdline(int idx, const char *cmdline) | |
bc0c38d1 | 2222 | { |
85f726a3 | 2223 | strncpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); |
939c7a4f YY |
2224 | } |
2225 | ||
2226 | static int allocate_cmdlines_buffer(unsigned int val, | |
2227 | struct saved_cmdlines_buffer *s) | |
2228 | { | |
6da2ec56 KC |
2229 | s->map_cmdline_to_pid = kmalloc_array(val, |
2230 | sizeof(*s->map_cmdline_to_pid), | |
2231 | GFP_KERNEL); | |
939c7a4f YY |
2232 | if (!s->map_cmdline_to_pid) |
2233 | return -ENOMEM; | |
2234 | ||
6da2ec56 | 2235 | s->saved_cmdlines = kmalloc_array(TASK_COMM_LEN, val, GFP_KERNEL); |
939c7a4f YY |
2236 | if (!s->saved_cmdlines) { |
2237 | kfree(s->map_cmdline_to_pid); | |
2238 | return -ENOMEM; | |
2239 | } | |
2240 | ||
2241 | s->cmdline_idx = 0; | |
2242 | s->cmdline_num = val; | |
2243 | memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP, | |
2244 | sizeof(s->map_pid_to_cmdline)); | |
2245 | memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP, | |
2246 | val * sizeof(*s->map_cmdline_to_pid)); | |
2247 | ||
2248 | return 0; | |
2249 | } | |
2250 | ||
2251 | static int trace_create_savedcmd(void) | |
2252 | { | |
2253 | int ret; | |
2254 | ||
a6af8fbf | 2255 | savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL); |
939c7a4f YY |
2256 | if (!savedcmd) |
2257 | return -ENOMEM; | |
2258 | ||
2259 | ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd); | |
2260 | if (ret < 0) { | |
2261 | kfree(savedcmd); | |
2262 | savedcmd = NULL; | |
2263 | return -ENOMEM; | |
2264 | } | |
2265 | ||
2266 | return 0; | |
bc0c38d1 SR |
2267 | } |
2268 | ||
b5130b1e CE |
2269 | int is_tracing_stopped(void) |
2270 | { | |
2b6080f2 | 2271 | return global_trace.stop_count; |
b5130b1e CE |
2272 | } |
2273 | ||
0f048701 SR |
2274 | /** |
2275 | * tracing_start - quick start of the tracer | |
2276 | * | |
2277 | * If tracing is enabled but was stopped by tracing_stop, | |
2278 | * this will start the tracer back up. | |
2279 | */ | |
2280 | void tracing_start(void) | |
2281 | { | |
13292494 | 2282 | struct trace_buffer *buffer; |
0f048701 SR |
2283 | unsigned long flags; |
2284 | ||
2285 | if (tracing_disabled) | |
2286 | return; | |
2287 | ||
2b6080f2 SR |
2288 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
2289 | if (--global_trace.stop_count) { | |
2290 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
2291 | /* Someone screwed up their debugging */ |
2292 | WARN_ON_ONCE(1); | |
2b6080f2 | 2293 | global_trace.stop_count = 0; |
b06a8301 | 2294 | } |
0f048701 SR |
2295 | goto out; |
2296 | } | |
2297 | ||
a2f80714 | 2298 | /* Prevent the buffers from switching */ |
0b9b12c1 | 2299 | arch_spin_lock(&global_trace.max_lock); |
0f048701 | 2300 | |
1c5eb448 | 2301 | buffer = global_trace.array_buffer.buffer; |
0f048701 SR |
2302 | if (buffer) |
2303 | ring_buffer_record_enable(buffer); | |
2304 | ||
12883efb SRRH |
2305 | #ifdef CONFIG_TRACER_MAX_TRACE |
2306 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
2307 | if (buffer) |
2308 | ring_buffer_record_enable(buffer); | |
12883efb | 2309 | #endif |
0f048701 | 2310 | |
0b9b12c1 | 2311 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 2312 | |
0f048701 | 2313 | out: |
2b6080f2 SR |
2314 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
2315 | } | |
2316 | ||
2317 | static void tracing_start_tr(struct trace_array *tr) | |
2318 | { | |
13292494 | 2319 | struct trace_buffer *buffer; |
2b6080f2 SR |
2320 | unsigned long flags; |
2321 | ||
2322 | if (tracing_disabled) | |
2323 | return; | |
2324 | ||
2325 | /* If global, we need to also start the max tracer */ | |
2326 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
2327 | return tracing_start(); | |
2328 | ||
2329 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
2330 | ||
2331 | if (--tr->stop_count) { | |
2332 | if (tr->stop_count < 0) { | |
2333 | /* Someone screwed up their debugging */ | |
2334 | WARN_ON_ONCE(1); | |
2335 | tr->stop_count = 0; | |
2336 | } | |
2337 | goto out; | |
2338 | } | |
2339 | ||
1c5eb448 | 2340 | buffer = tr->array_buffer.buffer; |
2b6080f2 SR |
2341 | if (buffer) |
2342 | ring_buffer_record_enable(buffer); | |
2343 | ||
2344 | out: | |
2345 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
2346 | } |
2347 | ||
2348 | /** | |
2349 | * tracing_stop - quick stop of the tracer | |
2350 | * | |
2351 | * Light weight way to stop tracing. Use in conjunction with | |
2352 | * tracing_start. | |
2353 | */ | |
2354 | void tracing_stop(void) | |
2355 | { | |
13292494 | 2356 | struct trace_buffer *buffer; |
0f048701 SR |
2357 | unsigned long flags; |
2358 | ||
2b6080f2 SR |
2359 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
2360 | if (global_trace.stop_count++) | |
0f048701 SR |
2361 | goto out; |
2362 | ||
a2f80714 | 2363 | /* Prevent the buffers from switching */ |
0b9b12c1 | 2364 | arch_spin_lock(&global_trace.max_lock); |
a2f80714 | 2365 | |
1c5eb448 | 2366 | buffer = global_trace.array_buffer.buffer; |
0f048701 SR |
2367 | if (buffer) |
2368 | ring_buffer_record_disable(buffer); | |
2369 | ||
12883efb SRRH |
2370 | #ifdef CONFIG_TRACER_MAX_TRACE |
2371 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
2372 | if (buffer) |
2373 | ring_buffer_record_disable(buffer); | |
12883efb | 2374 | #endif |
0f048701 | 2375 | |
0b9b12c1 | 2376 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 2377 | |
0f048701 | 2378 | out: |
2b6080f2 SR |
2379 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
2380 | } | |
2381 | ||
2382 | static void tracing_stop_tr(struct trace_array *tr) | |
2383 | { | |
13292494 | 2384 | struct trace_buffer *buffer; |
2b6080f2 SR |
2385 | unsigned long flags; |
2386 | ||
2387 | /* If global, we need to also stop the max tracer */ | |
2388 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
2389 | return tracing_stop(); | |
2390 | ||
2391 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
2392 | if (tr->stop_count++) | |
2393 | goto out; | |
2394 | ||
1c5eb448 | 2395 | buffer = tr->array_buffer.buffer; |
2b6080f2 SR |
2396 | if (buffer) |
2397 | ring_buffer_record_disable(buffer); | |
2398 | ||
2399 | out: | |
2400 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
2401 | } |
2402 | ||
379cfdac | 2403 | static int trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 2404 | { |
785e3c0a | 2405 | unsigned tpid, idx; |
bc0c38d1 | 2406 | |
eaf260ac JF |
2407 | /* treat recording of idle task as a success */ |
2408 | if (!tsk->pid) | |
2409 | return 1; | |
2410 | ||
785e3c0a | 2411 | tpid = tsk->pid & (PID_MAX_DEFAULT - 1); |
bc0c38d1 SR |
2412 | |
2413 | /* | |
2414 | * It's not the end of the world if we don't get | |
2415 | * the lock, but we also don't want to spin | |
2416 | * nor do we want to disable interrupts, | |
2417 | * so if we miss here, then better luck next time. | |
2418 | */ | |
0199c4e6 | 2419 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
379cfdac | 2420 | return 0; |
bc0c38d1 | 2421 | |
785e3c0a | 2422 | idx = savedcmd->map_pid_to_cmdline[tpid]; |
2c7eea4c | 2423 | if (idx == NO_CMDLINE_MAP) { |
939c7a4f | 2424 | idx = (savedcmd->cmdline_idx + 1) % savedcmd->cmdline_num; |
bc0c38d1 | 2425 | |
785e3c0a | 2426 | savedcmd->map_pid_to_cmdline[tpid] = idx; |
939c7a4f | 2427 | savedcmd->cmdline_idx = idx; |
bc0c38d1 SR |
2428 | } |
2429 | ||
785e3c0a | 2430 | savedcmd->map_cmdline_to_pid[idx] = tsk->pid; |
939c7a4f | 2431 | set_cmdline(idx, tsk->comm); |
bc0c38d1 | 2432 | |
0199c4e6 | 2433 | arch_spin_unlock(&trace_cmdline_lock); |
379cfdac SRRH |
2434 | |
2435 | return 1; | |
bc0c38d1 SR |
2436 | } |
2437 | ||
4c27e756 | 2438 | static void __trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 2439 | { |
bc0c38d1 | 2440 | unsigned map; |
785e3c0a | 2441 | int tpid; |
bc0c38d1 | 2442 | |
4ca53085 SR |
2443 | if (!pid) { |
2444 | strcpy(comm, "<idle>"); | |
2445 | return; | |
2446 | } | |
bc0c38d1 | 2447 | |
74bf4076 SR |
2448 | if (WARN_ON_ONCE(pid < 0)) { |
2449 | strcpy(comm, "<XXX>"); | |
2450 | return; | |
2451 | } | |
2452 | ||
785e3c0a SRV |
2453 | tpid = pid & (PID_MAX_DEFAULT - 1); |
2454 | map = savedcmd->map_pid_to_cmdline[tpid]; | |
2455 | if (map != NO_CMDLINE_MAP) { | |
2456 | tpid = savedcmd->map_cmdline_to_pid[map]; | |
2457 | if (tpid == pid) { | |
2458 | strlcpy(comm, get_saved_cmdlines(map), TASK_COMM_LEN); | |
2459 | return; | |
2460 | } | |
4ca53085 | 2461 | } |
785e3c0a | 2462 | strcpy(comm, "<...>"); |
4c27e756 SRRH |
2463 | } |
2464 | ||
2465 | void trace_find_cmdline(int pid, char comm[]) | |
2466 | { | |
2467 | preempt_disable(); | |
2468 | arch_spin_lock(&trace_cmdline_lock); | |
2469 | ||
2470 | __trace_find_cmdline(pid, comm); | |
bc0c38d1 | 2471 | |
0199c4e6 | 2472 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 2473 | preempt_enable(); |
bc0c38d1 SR |
2474 | } |
2475 | ||
4030a6e6 PB |
2476 | static int *trace_find_tgid_ptr(int pid) |
2477 | { | |
2478 | /* | |
2479 | * Pairs with the smp_store_release in set_tracer_flag() to ensure that | |
2480 | * if we observe a non-NULL tgid_map then we also observe the correct | |
2481 | * tgid_map_max. | |
2482 | */ | |
2483 | int *map = smp_load_acquire(&tgid_map); | |
2484 | ||
2485 | if (unlikely(!map || pid > tgid_map_max)) | |
2486 | return NULL; | |
2487 | ||
2488 | return &map[pid]; | |
2489 | } | |
2490 | ||
d914ba37 JF |
2491 | int trace_find_tgid(int pid) |
2492 | { | |
4030a6e6 | 2493 | int *ptr = trace_find_tgid_ptr(pid); |
d914ba37 | 2494 | |
4030a6e6 | 2495 | return ptr ? *ptr : 0; |
d914ba37 JF |
2496 | } |
2497 | ||
2498 | static int trace_save_tgid(struct task_struct *tsk) | |
2499 | { | |
4030a6e6 PB |
2500 | int *ptr; |
2501 | ||
bd45d34d JF |
2502 | /* treat recording of idle task as a success */ |
2503 | if (!tsk->pid) | |
2504 | return 1; | |
2505 | ||
4030a6e6 PB |
2506 | ptr = trace_find_tgid_ptr(tsk->pid); |
2507 | if (!ptr) | |
d914ba37 JF |
2508 | return 0; |
2509 | ||
4030a6e6 | 2510 | *ptr = tsk->tgid; |
d914ba37 JF |
2511 | return 1; |
2512 | } | |
2513 | ||
2514 | static bool tracing_record_taskinfo_skip(int flags) | |
2515 | { | |
2516 | if (unlikely(!(flags & (TRACE_RECORD_CMDLINE | TRACE_RECORD_TGID)))) | |
2517 | return true; | |
d914ba37 JF |
2518 | if (!__this_cpu_read(trace_taskinfo_save)) |
2519 | return true; | |
2520 | return false; | |
2521 | } | |
2522 | ||
2523 | /** | |
2524 | * tracing_record_taskinfo - record the task info of a task | |
2525 | * | |
c68c9ec1 JK |
2526 | * @task: task to record |
2527 | * @flags: TRACE_RECORD_CMDLINE for recording comm | |
2528 | * TRACE_RECORD_TGID for recording tgid | |
d914ba37 JF |
2529 | */ |
2530 | void tracing_record_taskinfo(struct task_struct *task, int flags) | |
2531 | { | |
29b1a8ad JF |
2532 | bool done; |
2533 | ||
d914ba37 JF |
2534 | if (tracing_record_taskinfo_skip(flags)) |
2535 | return; | |
29b1a8ad JF |
2536 | |
2537 | /* | |
2538 | * Record as much task information as possible. If some fail, continue | |
2539 | * to try to record the others. | |
2540 | */ | |
2541 | done = !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(task); | |
2542 | done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(task); | |
2543 | ||
2544 | /* If recording any information failed, retry again soon. */ | |
2545 | if (!done) | |
d914ba37 JF |
2546 | return; |
2547 | ||
2548 | __this_cpu_write(trace_taskinfo_save, false); | |
2549 | } | |
2550 | ||
2551 | /** | |
2552 | * tracing_record_taskinfo_sched_switch - record task info for sched_switch | |
2553 | * | |
c68c9ec1 JK |
2554 | * @prev: previous task during sched_switch |
2555 | * @next: next task during sched_switch | |
2556 | * @flags: TRACE_RECORD_CMDLINE for recording comm | |
2557 | * TRACE_RECORD_TGID for recording tgid | |
d914ba37 JF |
2558 | */ |
2559 | void tracing_record_taskinfo_sched_switch(struct task_struct *prev, | |
2560 | struct task_struct *next, int flags) | |
bc0c38d1 | 2561 | { |
29b1a8ad JF |
2562 | bool done; |
2563 | ||
d914ba37 JF |
2564 | if (tracing_record_taskinfo_skip(flags)) |
2565 | return; | |
2566 | ||
29b1a8ad JF |
2567 | /* |
2568 | * Record as much task information as possible. If some fail, continue | |
2569 | * to try to record the others. | |
2570 | */ | |
2571 | done = !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(prev); | |
2572 | done &= !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(next); | |
2573 | done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(prev); | |
2574 | done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(next); | |
bc0c38d1 | 2575 | |
29b1a8ad JF |
2576 | /* If recording any information failed, retry again soon. */ |
2577 | if (!done) | |
7ffbd48d SR |
2578 | return; |
2579 | ||
d914ba37 JF |
2580 | __this_cpu_write(trace_taskinfo_save, false); |
2581 | } | |
2582 | ||
2583 | /* Helpers to record a specific task information */ | |
2584 | void tracing_record_cmdline(struct task_struct *task) | |
2585 | { | |
2586 | tracing_record_taskinfo(task, TRACE_RECORD_CMDLINE); | |
2587 | } | |
2588 | ||
2589 | void tracing_record_tgid(struct task_struct *task) | |
2590 | { | |
2591 | tracing_record_taskinfo(task, TRACE_RECORD_TGID); | |
bc0c38d1 SR |
2592 | } |
2593 | ||
af0009fc SRV |
2594 | /* |
2595 | * Several functions return TRACE_TYPE_PARTIAL_LINE if the trace_seq | |
2596 | * overflowed, and TRACE_TYPE_HANDLED otherwise. This helper function | |
2597 | * simplifies those functions and keeps them in sync. | |
2598 | */ | |
2599 | enum print_line_t trace_handle_return(struct trace_seq *s) | |
2600 | { | |
2601 | return trace_seq_has_overflowed(s) ? | |
2602 | TRACE_TYPE_PARTIAL_LINE : TRACE_TYPE_HANDLED; | |
2603 | } | |
2604 | EXPORT_SYMBOL_GPL(trace_handle_return); | |
2605 | ||
54357f0c TG |
2606 | static unsigned short migration_disable_value(void) |
2607 | { | |
2608 | #if defined(CONFIG_SMP) | |
2609 | return current->migration_disabled; | |
2610 | #else | |
2611 | return 0; | |
2612 | #endif | |
2613 | } | |
2614 | ||
0c02006e | 2615 | unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status) |
bc0c38d1 | 2616 | { |
0c02006e | 2617 | unsigned int trace_flags = irqs_status; |
36590c50 | 2618 | unsigned int pc; |
bc0c38d1 | 2619 | |
36590c50 | 2620 | pc = preempt_count(); |
bc0c38d1 | 2621 | |
36590c50 SAS |
2622 | if (pc & NMI_MASK) |
2623 | trace_flags |= TRACE_FLAG_NMI; | |
2624 | if (pc & HARDIRQ_MASK) | |
2625 | trace_flags |= TRACE_FLAG_HARDIRQ; | |
fe427886 | 2626 | if (in_serving_softirq()) |
36590c50 SAS |
2627 | trace_flags |= TRACE_FLAG_SOFTIRQ; |
2628 | ||
2629 | if (tif_need_resched()) | |
2630 | trace_flags |= TRACE_FLAG_NEED_RESCHED; | |
2631 | if (test_preempt_need_resched()) | |
2632 | trace_flags |= TRACE_FLAG_PREEMPT_RESCHED; | |
54357f0c TG |
2633 | return (trace_flags << 16) | (min_t(unsigned int, pc & 0xff, 0xf)) | |
2634 | (min_t(unsigned int, migration_disable_value(), 0xf)) << 4; | |
bc0c38d1 SR |
2635 | } |
2636 | ||
e77405ad | 2637 | struct ring_buffer_event * |
13292494 | 2638 | trace_buffer_lock_reserve(struct trace_buffer *buffer, |
e77405ad SR |
2639 | int type, |
2640 | unsigned long len, | |
36590c50 | 2641 | unsigned int trace_ctx) |
51a763dd | 2642 | { |
36590c50 | 2643 | return __trace_buffer_lock_reserve(buffer, type, len, trace_ctx); |
0fc1b09f SRRH |
2644 | } |
2645 | ||
2646 | DEFINE_PER_CPU(struct ring_buffer_event *, trace_buffered_event); | |
2647 | DEFINE_PER_CPU(int, trace_buffered_event_cnt); | |
2648 | static int trace_buffered_event_ref; | |
2649 | ||
2650 | /** | |
2651 | * trace_buffered_event_enable - enable buffering events | |
2652 | * | |
2653 | * When events are being filtered, it is quicker to use a temporary | |
2654 | * buffer to write the event data into if there's a likely chance | |
2655 | * that it will not be committed. The discard of the ring buffer | |
2656 | * is not as fast as committing, and is much slower than copying | |
2657 | * a commit. | |
2658 | * | |
2659 | * When an event is to be filtered, allocate per cpu buffers to | |
2660 | * write the event data into, and if the event is filtered and discarded | |
2661 | * it is simply dropped, otherwise, the entire data is to be committed | |
2662 | * in one shot. | |
2663 | */ | |
2664 | void trace_buffered_event_enable(void) | |
2665 | { | |
2666 | struct ring_buffer_event *event; | |
2667 | struct page *page; | |
2668 | int cpu; | |
51a763dd | 2669 | |
0fc1b09f SRRH |
2670 | WARN_ON_ONCE(!mutex_is_locked(&event_mutex)); |
2671 | ||
2672 | if (trace_buffered_event_ref++) | |
2673 | return; | |
2674 | ||
2675 | for_each_tracing_cpu(cpu) { | |
2676 | page = alloc_pages_node(cpu_to_node(cpu), | |
2677 | GFP_KERNEL | __GFP_NORETRY, 0); | |
2678 | if (!page) | |
2679 | goto failed; | |
2680 | ||
2681 | event = page_address(page); | |
2682 | memset(event, 0, sizeof(*event)); | |
2683 | ||
2684 | per_cpu(trace_buffered_event, cpu) = event; | |
2685 | ||
2686 | preempt_disable(); | |
2687 | if (cpu == smp_processor_id() && | |
b427e765 | 2688 | __this_cpu_read(trace_buffered_event) != |
0fc1b09f SRRH |
2689 | per_cpu(trace_buffered_event, cpu)) |
2690 | WARN_ON_ONCE(1); | |
2691 | preempt_enable(); | |
51a763dd ACM |
2692 | } |
2693 | ||
0fc1b09f SRRH |
2694 | return; |
2695 | failed: | |
2696 | trace_buffered_event_disable(); | |
2697 | } | |
2698 | ||
2699 | static void enable_trace_buffered_event(void *data) | |
2700 | { | |
2701 | /* Probably not needed, but do it anyway */ | |
2702 | smp_rmb(); | |
2703 | this_cpu_dec(trace_buffered_event_cnt); | |
2704 | } | |
2705 | ||
2706 | static void disable_trace_buffered_event(void *data) | |
2707 | { | |
2708 | this_cpu_inc(trace_buffered_event_cnt); | |
2709 | } | |
2710 | ||
2711 | /** | |
2712 | * trace_buffered_event_disable - disable buffering events | |
2713 | * | |
2714 | * When a filter is removed, it is faster to not use the buffered | |
2715 | * events, and to commit directly into the ring buffer. Free up | |
2716 | * the temp buffers when there are no more users. This requires | |
2717 | * special synchronization with current events. | |
2718 | */ | |
2719 | void trace_buffered_event_disable(void) | |
2720 | { | |
2721 | int cpu; | |
2722 | ||
2723 | WARN_ON_ONCE(!mutex_is_locked(&event_mutex)); | |
2724 | ||
2725 | if (WARN_ON_ONCE(!trace_buffered_event_ref)) | |
2726 | return; | |
2727 | ||
2728 | if (--trace_buffered_event_ref) | |
2729 | return; | |
2730 | ||
2731 | preempt_disable(); | |
2732 | /* For each CPU, set the buffer as used. */ | |
2733 | smp_call_function_many(tracing_buffer_mask, | |
2734 | disable_trace_buffered_event, NULL, 1); | |
2735 | preempt_enable(); | |
2736 | ||
2737 | /* Wait for all current users to finish */ | |
74401729 | 2738 | synchronize_rcu(); |
0fc1b09f SRRH |
2739 | |
2740 | for_each_tracing_cpu(cpu) { | |
2741 | free_page((unsigned long)per_cpu(trace_buffered_event, cpu)); | |
2742 | per_cpu(trace_buffered_event, cpu) = NULL; | |
2743 | } | |
2744 | /* | |
2745 | * Make sure trace_buffered_event is NULL before clearing | |
2746 | * trace_buffered_event_cnt. | |
2747 | */ | |
2748 | smp_wmb(); | |
2749 | ||
2750 | preempt_disable(); | |
2751 | /* Do the work on each cpu */ | |
2752 | smp_call_function_many(tracing_buffer_mask, | |
2753 | enable_trace_buffered_event, NULL, 1); | |
2754 | preempt_enable(); | |
51a763dd | 2755 | } |
51a763dd | 2756 | |
13292494 | 2757 | static struct trace_buffer *temp_buffer; |
2c4a33ab | 2758 | |
ccb469a1 | 2759 | struct ring_buffer_event * |
13292494 | 2760 | trace_event_buffer_lock_reserve(struct trace_buffer **current_rb, |
7f1d2f82 | 2761 | struct trace_event_file *trace_file, |
ccb469a1 | 2762 | int type, unsigned long len, |
36590c50 | 2763 | unsigned int trace_ctx) |
ccb469a1 | 2764 | { |
2c4a33ab | 2765 | struct ring_buffer_event *entry; |
b94bc80d | 2766 | struct trace_array *tr = trace_file->tr; |
0fc1b09f | 2767 | int val; |
2c4a33ab | 2768 | |
b94bc80d | 2769 | *current_rb = tr->array_buffer.buffer; |
0fc1b09f | 2770 | |
b94bc80d SRV |
2771 | if (!tr->no_filter_buffering_ref && |
2772 | (trace_file->flags & (EVENT_FILE_FL_SOFT_DISABLED | EVENT_FILE_FL_FILTERED)) && | |
0fc1b09f | 2773 | (entry = this_cpu_read(trace_buffered_event))) { |
8f0901cd SRV |
2774 | /* |
2775 | * Filtering is on, so try to use the per cpu buffer first. | |
2776 | * This buffer will simulate a ring_buffer_event, | |
2777 | * where the type_len is zero and the array[0] will | |
2778 | * hold the full length. | |
2779 | * (see include/linux/ring-buffer.h for details on | |
2780 | * how the ring_buffer_event is structured). | |
2781 | * | |
2782 | * Using a temp buffer during filtering and copying it | |
2783 | * on a matched filter is quicker than writing directly | |
2784 | * into the ring buffer and then discarding it when | |
2785 | * it doesn't match. That is because the discard | |
2786 | * requires several atomic operations to get right. | |
2787 | * Copying on match and doing nothing on a failed match | |
2788 | * is still quicker than no copy on match, but having | |
2789 | * to discard out of the ring buffer on a failed match. | |
2790 | */ | |
faa76a6c SRV |
2791 | int max_len = PAGE_SIZE - struct_size(entry, array, 1); |
2792 | ||
0fc1b09f | 2793 | val = this_cpu_inc_return(trace_buffered_event_cnt); |
8f0901cd SRV |
2794 | |
2795 | /* | |
2796 | * Preemption is disabled, but interrupts and NMIs | |
2797 | * can still come in now. If that happens after | |
2798 | * the above increment, then it will have to go | |
2799 | * back to the old method of allocating the event | |
2800 | * on the ring buffer, and if the filter fails, it | |
2801 | * will have to call ring_buffer_discard_commit() | |
2802 | * to remove it. | |
2803 | * | |
2804 | * Need to also check the unlikely case that the | |
2805 | * length is bigger than the temp buffer size. | |
2806 | * If that happens, then the reserve is pretty much | |
2807 | * guaranteed to fail, as the ring buffer currently | |
2808 | * only allows events less than a page. But that may | |
2809 | * change in the future, so let the ring buffer reserve | |
2810 | * handle the failure in that case. | |
2811 | */ | |
faa76a6c | 2812 | if (val == 1 && likely(len <= max_len)) { |
36590c50 | 2813 | trace_event_setup(entry, type, trace_ctx); |
0fc1b09f SRRH |
2814 | entry->array[0] = len; |
2815 | return entry; | |
2816 | } | |
2817 | this_cpu_dec(trace_buffered_event_cnt); | |
2818 | } | |
2819 | ||
36590c50 SAS |
2820 | entry = __trace_buffer_lock_reserve(*current_rb, type, len, |
2821 | trace_ctx); | |
2c4a33ab SRRH |
2822 | /* |
2823 | * If tracing is off, but we have triggers enabled | |
2824 | * we still need to look at the event data. Use the temp_buffer | |
906695e5 | 2825 | * to store the trace event for the trigger to use. It's recursive |
2c4a33ab SRRH |
2826 | * safe and will not be recorded anywhere. |
2827 | */ | |
5d6ad960 | 2828 | if (!entry && trace_file->flags & EVENT_FILE_FL_TRIGGER_COND) { |
2c4a33ab | 2829 | *current_rb = temp_buffer; |
36590c50 SAS |
2830 | entry = __trace_buffer_lock_reserve(*current_rb, type, len, |
2831 | trace_ctx); | |
2c4a33ab SRRH |
2832 | } |
2833 | return entry; | |
ccb469a1 SR |
2834 | } |
2835 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
2836 | ||
42391745 SRRH |
2837 | static DEFINE_SPINLOCK(tracepoint_iter_lock); |
2838 | static DEFINE_MUTEX(tracepoint_printk_mutex); | |
2839 | ||
2840 | static void output_printk(struct trace_event_buffer *fbuffer) | |
2841 | { | |
2842 | struct trace_event_call *event_call; | |
d8d0c245 | 2843 | struct trace_event_file *file; |
42391745 SRRH |
2844 | struct trace_event *event; |
2845 | unsigned long flags; | |
2846 | struct trace_iterator *iter = tracepoint_print_iter; | |
2847 | ||
2848 | /* We should never get here if iter is NULL */ | |
2849 | if (WARN_ON_ONCE(!iter)) | |
2850 | return; | |
2851 | ||
2852 | event_call = fbuffer->trace_file->event_call; | |
2853 | if (!event_call || !event_call->event.funcs || | |
2854 | !event_call->event.funcs->trace) | |
2855 | return; | |
2856 | ||
d8d0c245 MH |
2857 | file = fbuffer->trace_file; |
2858 | if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) || | |
2859 | (unlikely(file->flags & EVENT_FILE_FL_FILTERED) && | |
2860 | !filter_match_preds(file->filter, fbuffer->entry))) | |
2861 | return; | |
2862 | ||
42391745 SRRH |
2863 | event = &fbuffer->trace_file->event_call->event; |
2864 | ||
2865 | spin_lock_irqsave(&tracepoint_iter_lock, flags); | |
2866 | trace_seq_init(&iter->seq); | |
2867 | iter->ent = fbuffer->entry; | |
2868 | event_call->event.funcs->trace(iter, 0, event); | |
2869 | trace_seq_putc(&iter->seq, 0); | |
2870 | printk("%s", iter->seq.buffer); | |
2871 | ||
2872 | spin_unlock_irqrestore(&tracepoint_iter_lock, flags); | |
2873 | } | |
2874 | ||
2875 | int tracepoint_printk_sysctl(struct ctl_table *table, int write, | |
32927393 | 2876 | void *buffer, size_t *lenp, |
42391745 SRRH |
2877 | loff_t *ppos) |
2878 | { | |
2879 | int save_tracepoint_printk; | |
2880 | int ret; | |
2881 | ||
2882 | mutex_lock(&tracepoint_printk_mutex); | |
2883 | save_tracepoint_printk = tracepoint_printk; | |
2884 | ||
2885 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
2886 | ||
2887 | /* | |
2888 | * This will force exiting early, as tracepoint_printk | |
2889 | * is always zero when tracepoint_printk_iter is not allocated | |
2890 | */ | |
2891 | if (!tracepoint_print_iter) | |
2892 | tracepoint_printk = 0; | |
2893 | ||
2894 | if (save_tracepoint_printk == tracepoint_printk) | |
2895 | goto out; | |
2896 | ||
2897 | if (tracepoint_printk) | |
2898 | static_key_enable(&tracepoint_printk_key.key); | |
2899 | else | |
2900 | static_key_disable(&tracepoint_printk_key.key); | |
2901 | ||
2902 | out: | |
2903 | mutex_unlock(&tracepoint_printk_mutex); | |
2904 | ||
2905 | return ret; | |
2906 | } | |
2907 | ||
2908 | void trace_event_buffer_commit(struct trace_event_buffer *fbuffer) | |
2909 | { | |
6c34df6f PL |
2910 | enum event_trigger_type tt = ETT_NONE; |
2911 | struct trace_event_file *file = fbuffer->trace_file; | |
2912 | ||
2913 | if (__event_trigger_test_discard(file, fbuffer->buffer, fbuffer->event, | |
2914 | fbuffer->entry, &tt)) | |
2915 | goto discard; | |
2916 | ||
42391745 SRRH |
2917 | if (static_key_false(&tracepoint_printk_key.key)) |
2918 | output_printk(fbuffer); | |
2919 | ||
8ab7a2b7 TZ |
2920 | if (static_branch_unlikely(&trace_event_exports_enabled)) |
2921 | ftrace_exports(fbuffer->event, TRACE_EXPORT_EVENT); | |
6c34df6f PL |
2922 | |
2923 | trace_buffer_unlock_commit_regs(file->tr, fbuffer->buffer, | |
2924 | fbuffer->event, fbuffer->trace_ctx, fbuffer->regs); | |
2925 | ||
2926 | discard: | |
2927 | if (tt) | |
2928 | event_triggers_post_call(file, tt); | |
2929 | ||
42391745 SRRH |
2930 | } |
2931 | EXPORT_SYMBOL_GPL(trace_event_buffer_commit); | |
2932 | ||
2ee5b92a SRV |
2933 | /* |
2934 | * Skip 3: | |
2935 | * | |
2936 | * trace_buffer_unlock_commit_regs() | |
2937 | * trace_event_buffer_commit() | |
2938 | * trace_event_raw_event_xxx() | |
13cf912b | 2939 | */ |
2ee5b92a SRV |
2940 | # define STACK_SKIP 3 |
2941 | ||
b7f0c959 | 2942 | void trace_buffer_unlock_commit_regs(struct trace_array *tr, |
13292494 | 2943 | struct trace_buffer *buffer, |
0d5c6e1c | 2944 | struct ring_buffer_event *event, |
36590c50 | 2945 | unsigned int trace_ctx, |
0d5c6e1c | 2946 | struct pt_regs *regs) |
1fd8df2c | 2947 | { |
7ffbd48d | 2948 | __buffer_unlock_commit(buffer, event); |
1fd8df2c | 2949 | |
be54f69c | 2950 | /* |
2ee5b92a | 2951 | * If regs is not set, then skip the necessary functions. |
be54f69c SRRH |
2952 | * Note, we can still get here via blktrace, wakeup tracer |
2953 | * and mmiotrace, but that's ok if they lose a function or | |
2ee5b92a | 2954 | * two. They are not that meaningful. |
be54f69c | 2955 | */ |
36590c50 SAS |
2956 | ftrace_trace_stack(tr, buffer, trace_ctx, regs ? 0 : STACK_SKIP, regs); |
2957 | ftrace_trace_userstack(tr, buffer, trace_ctx); | |
1fd8df2c | 2958 | } |
1fd8df2c | 2959 | |
52ffabe3 SRRH |
2960 | /* |
2961 | * Similar to trace_buffer_unlock_commit_regs() but do not dump stack. | |
2962 | */ | |
2963 | void | |
13292494 | 2964 | trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer, |
52ffabe3 SRRH |
2965 | struct ring_buffer_event *event) |
2966 | { | |
2967 | __buffer_unlock_commit(buffer, event); | |
2968 | } | |
2969 | ||
e309b41d | 2970 | void |
36590c50 SAS |
2971 | trace_function(struct trace_array *tr, unsigned long ip, unsigned long |
2972 | parent_ip, unsigned int trace_ctx) | |
bc0c38d1 | 2973 | { |
2425bcb9 | 2974 | struct trace_event_call *call = &event_function; |
13292494 | 2975 | struct trace_buffer *buffer = tr->array_buffer.buffer; |
3928a8a2 | 2976 | struct ring_buffer_event *event; |
777e208d | 2977 | struct ftrace_entry *entry; |
bc0c38d1 | 2978 | |
3e9a8aad | 2979 | event = __trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
36590c50 | 2980 | trace_ctx); |
3928a8a2 SR |
2981 | if (!event) |
2982 | return; | |
2983 | entry = ring_buffer_event_data(event); | |
777e208d SR |
2984 | entry->ip = ip; |
2985 | entry->parent_ip = parent_ip; | |
e1112b4d | 2986 | |
478409dd | 2987 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
8438f521 TZ |
2988 | if (static_branch_unlikely(&trace_function_exports_enabled)) |
2989 | ftrace_exports(event, TRACE_EXPORT_FUNCTION); | |
7ffbd48d | 2990 | __buffer_unlock_commit(buffer, event); |
478409dd | 2991 | } |
bc0c38d1 SR |
2992 | } |
2993 | ||
c0a0d0d3 | 2994 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 | 2995 | |
2a820bf7 TG |
2996 | /* Allow 4 levels of nesting: normal, softirq, irq, NMI */ |
2997 | #define FTRACE_KSTACK_NESTING 4 | |
2998 | ||
2999 | #define FTRACE_KSTACK_ENTRIES (PAGE_SIZE / FTRACE_KSTACK_NESTING) | |
3000 | ||
4a9bd3f1 | 3001 | struct ftrace_stack { |
2a820bf7 | 3002 | unsigned long calls[FTRACE_KSTACK_ENTRIES]; |
4a9bd3f1 SR |
3003 | }; |
3004 | ||
2a820bf7 TG |
3005 | |
3006 | struct ftrace_stacks { | |
3007 | struct ftrace_stack stacks[FTRACE_KSTACK_NESTING]; | |
4a9bd3f1 SR |
3008 | }; |
3009 | ||
2a820bf7 | 3010 | static DEFINE_PER_CPU(struct ftrace_stacks, ftrace_stacks); |
4a9bd3f1 SR |
3011 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); |
3012 | ||
13292494 | 3013 | static void __ftrace_trace_stack(struct trace_buffer *buffer, |
36590c50 SAS |
3014 | unsigned int trace_ctx, |
3015 | int skip, struct pt_regs *regs) | |
86387f7e | 3016 | { |
2425bcb9 | 3017 | struct trace_event_call *call = &event_kernel_stack; |
3928a8a2 | 3018 | struct ring_buffer_event *event; |
ee6dd0db | 3019 | unsigned int size, nr_entries; |
2a820bf7 | 3020 | struct ftrace_stack *fstack; |
777e208d | 3021 | struct stack_entry *entry; |
2a820bf7 | 3022 | int stackidx; |
4a9bd3f1 | 3023 | |
be54f69c | 3024 | /* |
2ee5b92a | 3025 | * Add one, for this function and the call to save_stack_trace() |
be54f69c SRRH |
3026 | * If regs is set, then these functions will not be in the way. |
3027 | */ | |
2ee5b92a | 3028 | #ifndef CONFIG_UNWINDER_ORC |
be54f69c | 3029 | if (!regs) |
ee6dd0db | 3030 | skip++; |
2ee5b92a | 3031 | #endif |
be54f69c | 3032 | |
4a9bd3f1 SR |
3033 | preempt_disable_notrace(); |
3034 | ||
2a820bf7 TG |
3035 | stackidx = __this_cpu_inc_return(ftrace_stack_reserve) - 1; |
3036 | ||
3037 | /* This should never happen. If it does, yell once and skip */ | |
906695e5 | 3038 | if (WARN_ON_ONCE(stackidx >= FTRACE_KSTACK_NESTING)) |
2a820bf7 TG |
3039 | goto out; |
3040 | ||
4a9bd3f1 | 3041 | /* |
2a820bf7 TG |
3042 | * The above __this_cpu_inc_return() is 'atomic' cpu local. An |
3043 | * interrupt will either see the value pre increment or post | |
3044 | * increment. If the interrupt happens pre increment it will have | |
3045 | * restored the counter when it returns. We just need a barrier to | |
3046 | * keep gcc from moving things around. | |
4a9bd3f1 SR |
3047 | */ |
3048 | barrier(); | |
4a9bd3f1 | 3049 | |
2a820bf7 | 3050 | fstack = this_cpu_ptr(ftrace_stacks.stacks) + stackidx; |
ee6dd0db | 3051 | size = ARRAY_SIZE(fstack->calls); |
4a9bd3f1 | 3052 | |
ee6dd0db TG |
3053 | if (regs) { |
3054 | nr_entries = stack_trace_save_regs(regs, fstack->calls, | |
3055 | size, skip); | |
3056 | } else { | |
3057 | nr_entries = stack_trace_save(fstack->calls, size, skip); | |
3058 | } | |
86387f7e | 3059 | |
ee6dd0db | 3060 | size = nr_entries * sizeof(unsigned long); |
3e9a8aad | 3061 | event = __trace_buffer_lock_reserve(buffer, TRACE_STACK, |
9deb193a SRV |
3062 | (sizeof(*entry) - sizeof(entry->caller)) + size, |
3063 | trace_ctx); | |
3928a8a2 | 3064 | if (!event) |
4a9bd3f1 SR |
3065 | goto out; |
3066 | entry = ring_buffer_event_data(event); | |
86387f7e | 3067 | |
ee6dd0db TG |
3068 | memcpy(&entry->caller, fstack->calls, size); |
3069 | entry->size = nr_entries; | |
86387f7e | 3070 | |
f306cc82 | 3071 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 3072 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
3073 | |
3074 | out: | |
3075 | /* Again, don't let gcc optimize things here */ | |
3076 | barrier(); | |
82146529 | 3077 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
3078 | preempt_enable_notrace(); |
3079 | ||
f0a920d5 IM |
3080 | } |
3081 | ||
2d34f489 | 3082 | static inline void ftrace_trace_stack(struct trace_array *tr, |
13292494 | 3083 | struct trace_buffer *buffer, |
36590c50 SAS |
3084 | unsigned int trace_ctx, |
3085 | int skip, struct pt_regs *regs) | |
53614991 | 3086 | { |
2d34f489 | 3087 | if (!(tr->trace_flags & TRACE_ITER_STACKTRACE)) |
53614991 SR |
3088 | return; |
3089 | ||
36590c50 | 3090 | __ftrace_trace_stack(buffer, trace_ctx, skip, regs); |
53614991 SR |
3091 | } |
3092 | ||
36590c50 SAS |
3093 | void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, |
3094 | int skip) | |
38697053 | 3095 | { |
13292494 | 3096 | struct trace_buffer *buffer = tr->array_buffer.buffer; |
a33d7d94 SRV |
3097 | |
3098 | if (rcu_is_watching()) { | |
36590c50 | 3099 | __ftrace_trace_stack(buffer, trace_ctx, skip, NULL); |
a33d7d94 SRV |
3100 | return; |
3101 | } | |
3102 | ||
3103 | /* | |
3104 | * When an NMI triggers, RCU is enabled via rcu_nmi_enter(), | |
3105 | * but if the above rcu_is_watching() failed, then the NMI | |
3106 | * triggered someplace critical, and rcu_irq_enter() should | |
3107 | * not be called from NMI. | |
3108 | */ | |
3109 | if (unlikely(in_nmi())) | |
3110 | return; | |
3111 | ||
a33d7d94 | 3112 | rcu_irq_enter_irqson(); |
36590c50 | 3113 | __ftrace_trace_stack(buffer, trace_ctx, skip, NULL); |
a33d7d94 | 3114 | rcu_irq_exit_irqson(); |
38697053 SR |
3115 | } |
3116 | ||
03889384 SR |
3117 | /** |
3118 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 3119 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 3120 | */ |
c142be8e | 3121 | void trace_dump_stack(int skip) |
03889384 | 3122 | { |
03889384 | 3123 | if (tracing_disabled || tracing_selftest_running) |
e36c5458 | 3124 | return; |
03889384 | 3125 | |
2ee5b92a SRV |
3126 | #ifndef CONFIG_UNWINDER_ORC |
3127 | /* Skip 1 to skip this function. */ | |
3128 | skip++; | |
3129 | #endif | |
1c5eb448 | 3130 | __ftrace_trace_stack(global_trace.array_buffer.buffer, |
36590c50 | 3131 | tracing_gen_ctx(), skip, NULL); |
03889384 | 3132 | } |
da387e5c | 3133 | EXPORT_SYMBOL_GPL(trace_dump_stack); |
03889384 | 3134 | |
c438f140 | 3135 | #ifdef CONFIG_USER_STACKTRACE_SUPPORT |
91e86e56 SR |
3136 | static DEFINE_PER_CPU(int, user_stack_count); |
3137 | ||
c438f140 | 3138 | static void |
bcee5278 | 3139 | ftrace_trace_userstack(struct trace_array *tr, |
36590c50 | 3140 | struct trace_buffer *buffer, unsigned int trace_ctx) |
02b67518 | 3141 | { |
2425bcb9 | 3142 | struct trace_event_call *call = &event_user_stack; |
8d7c6a96 | 3143 | struct ring_buffer_event *event; |
02b67518 | 3144 | struct userstack_entry *entry; |
02b67518 | 3145 | |
bcee5278 | 3146 | if (!(tr->trace_flags & TRACE_ITER_USERSTACKTRACE)) |
02b67518 TE |
3147 | return; |
3148 | ||
b6345879 SR |
3149 | /* |
3150 | * NMIs can not handle page faults, even with fix ups. | |
3151 | * The save user stack can (and often does) fault. | |
3152 | */ | |
3153 | if (unlikely(in_nmi())) | |
3154 | return; | |
02b67518 | 3155 | |
91e86e56 SR |
3156 | /* |
3157 | * prevent recursion, since the user stack tracing may | |
3158 | * trigger other kernel events. | |
3159 | */ | |
3160 | preempt_disable(); | |
3161 | if (__this_cpu_read(user_stack_count)) | |
3162 | goto out; | |
3163 | ||
3164 | __this_cpu_inc(user_stack_count); | |
3165 | ||
3e9a8aad | 3166 | event = __trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
36590c50 | 3167 | sizeof(*entry), trace_ctx); |
02b67518 | 3168 | if (!event) |
1dbd1951 | 3169 | goto out_drop_count; |
02b67518 | 3170 | entry = ring_buffer_event_data(event); |
02b67518 | 3171 | |
48659d31 | 3172 | entry->tgid = current->tgid; |
02b67518 TE |
3173 | memset(&entry->caller, 0, sizeof(entry->caller)); |
3174 | ||
ee6dd0db | 3175 | stack_trace_save_user(entry->caller, FTRACE_STACK_ENTRIES); |
f306cc82 | 3176 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 3177 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 3178 | |
1dbd1951 | 3179 | out_drop_count: |
91e86e56 | 3180 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
3181 | out: |
3182 | preempt_enable(); | |
02b67518 | 3183 | } |
c438f140 | 3184 | #else /* CONFIG_USER_STACKTRACE_SUPPORT */ |
bcee5278 SRV |
3185 | static void ftrace_trace_userstack(struct trace_array *tr, |
3186 | struct trace_buffer *buffer, | |
36590c50 | 3187 | unsigned int trace_ctx) |
02b67518 | 3188 | { |
02b67518 | 3189 | } |
c438f140 | 3190 | #endif /* !CONFIG_USER_STACKTRACE_SUPPORT */ |
02b67518 | 3191 | |
c0a0d0d3 FW |
3192 | #endif /* CONFIG_STACKTRACE */ |
3193 | ||
c658797f YKV |
3194 | static inline void |
3195 | func_repeats_set_delta_ts(struct func_repeats_entry *entry, | |
3196 | unsigned long long delta) | |
3197 | { | |
3198 | entry->bottom_delta_ts = delta & U32_MAX; | |
3199 | entry->top_delta_ts = (delta >> 32); | |
3200 | } | |
3201 | ||
3202 | void trace_last_func_repeats(struct trace_array *tr, | |
3203 | struct trace_func_repeats *last_info, | |
3204 | unsigned int trace_ctx) | |
3205 | { | |
3206 | struct trace_buffer *buffer = tr->array_buffer.buffer; | |
3207 | struct func_repeats_entry *entry; | |
3208 | struct ring_buffer_event *event; | |
3209 | u64 delta; | |
3210 | ||
3211 | event = __trace_buffer_lock_reserve(buffer, TRACE_FUNC_REPEATS, | |
3212 | sizeof(*entry), trace_ctx); | |
3213 | if (!event) | |
3214 | return; | |
3215 | ||
3216 | delta = ring_buffer_event_time_stamp(buffer, event) - | |
3217 | last_info->ts_last_call; | |
3218 | ||
3219 | entry = ring_buffer_event_data(event); | |
3220 | entry->ip = last_info->ip; | |
3221 | entry->parent_ip = last_info->parent_ip; | |
3222 | entry->count = last_info->count; | |
3223 | func_repeats_set_delta_ts(entry, delta); | |
3224 | ||
3225 | __buffer_unlock_commit(buffer, event); | |
3226 | } | |
3227 | ||
07d777fe SR |
3228 | /* created for use with alloc_percpu */ |
3229 | struct trace_buffer_struct { | |
e2ace001 AL |
3230 | int nesting; |
3231 | char buffer[4][TRACE_BUF_SIZE]; | |
07d777fe SR |
3232 | }; |
3233 | ||
3234 | static struct trace_buffer_struct *trace_percpu_buffer; | |
07d777fe SR |
3235 | |
3236 | /* | |
2b5894cc | 3237 | * This allows for lockless recording. If we're nested too deeply, then |
e2ace001 | 3238 | * this returns NULL. |
07d777fe SR |
3239 | */ |
3240 | static char *get_trace_buf(void) | |
3241 | { | |
e2ace001 | 3242 | struct trace_buffer_struct *buffer = this_cpu_ptr(trace_percpu_buffer); |
07d777fe | 3243 | |
e2ace001 | 3244 | if (!buffer || buffer->nesting >= 4) |
07d777fe SR |
3245 | return NULL; |
3246 | ||
3d9622c1 SRV |
3247 | buffer->nesting++; |
3248 | ||
3249 | /* Interrupts must see nesting incremented before we use the buffer */ | |
3250 | barrier(); | |
c1acb4ac | 3251 | return &buffer->buffer[buffer->nesting - 1][0]; |
e2ace001 AL |
3252 | } |
3253 | ||
3254 | static void put_trace_buf(void) | |
3255 | { | |
3d9622c1 SRV |
3256 | /* Don't let the decrement of nesting leak before this */ |
3257 | barrier(); | |
e2ace001 | 3258 | this_cpu_dec(trace_percpu_buffer->nesting); |
07d777fe SR |
3259 | } |
3260 | ||
3261 | static int alloc_percpu_trace_buffer(void) | |
3262 | { | |
3263 | struct trace_buffer_struct *buffers; | |
07d777fe | 3264 | |
38ce2a9e SRV |
3265 | if (trace_percpu_buffer) |
3266 | return 0; | |
3267 | ||
07d777fe | 3268 | buffers = alloc_percpu(struct trace_buffer_struct); |
24589e3a | 3269 | if (MEM_FAIL(!buffers, "Could not allocate percpu trace_printk buffer")) |
e2ace001 | 3270 | return -ENOMEM; |
07d777fe SR |
3271 | |
3272 | trace_percpu_buffer = buffers; | |
07d777fe | 3273 | return 0; |
07d777fe SR |
3274 | } |
3275 | ||
81698831 SR |
3276 | static int buffers_allocated; |
3277 | ||
07d777fe SR |
3278 | void trace_printk_init_buffers(void) |
3279 | { | |
07d777fe SR |
3280 | if (buffers_allocated) |
3281 | return; | |
3282 | ||
3283 | if (alloc_percpu_trace_buffer()) | |
3284 | return; | |
3285 | ||
2184db46 SR |
3286 | /* trace_printk() is for debug use only. Don't use it in production. */ |
3287 | ||
a395d6a7 JP |
3288 | pr_warn("\n"); |
3289 | pr_warn("**********************************************************\n"); | |
3290 | pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
3291 | pr_warn("** **\n"); | |
3292 | pr_warn("** trace_printk() being used. Allocating extra memory. **\n"); | |
3293 | pr_warn("** **\n"); | |
3294 | pr_warn("** This means that this is a DEBUG kernel and it is **\n"); | |
3295 | pr_warn("** unsafe for production use. **\n"); | |
3296 | pr_warn("** **\n"); | |
3297 | pr_warn("** If you see this message and you are not debugging **\n"); | |
3298 | pr_warn("** the kernel, report this immediately to your vendor! **\n"); | |
3299 | pr_warn("** **\n"); | |
3300 | pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
3301 | pr_warn("**********************************************************\n"); | |
07d777fe | 3302 | |
b382ede6 SR |
3303 | /* Expand the buffers to set size */ |
3304 | tracing_update_buffers(); | |
3305 | ||
07d777fe | 3306 | buffers_allocated = 1; |
81698831 SR |
3307 | |
3308 | /* | |
3309 | * trace_printk_init_buffers() can be called by modules. | |
3310 | * If that happens, then we need to start cmdline recording | |
3311 | * directly here. If the global_trace.buffer is already | |
3312 | * allocated here, then this was called by module code. | |
3313 | */ | |
1c5eb448 | 3314 | if (global_trace.array_buffer.buffer) |
81698831 SR |
3315 | tracing_start_cmdline_record(); |
3316 | } | |
f45d1225 | 3317 | EXPORT_SYMBOL_GPL(trace_printk_init_buffers); |
81698831 SR |
3318 | |
3319 | void trace_printk_start_comm(void) | |
3320 | { | |
3321 | /* Start tracing comms if trace printk is set */ | |
3322 | if (!buffers_allocated) | |
3323 | return; | |
3324 | tracing_start_cmdline_record(); | |
3325 | } | |
3326 | ||
3327 | static void trace_printk_start_stop_comm(int enabled) | |
3328 | { | |
3329 | if (!buffers_allocated) | |
3330 | return; | |
3331 | ||
3332 | if (enabled) | |
3333 | tracing_start_cmdline_record(); | |
3334 | else | |
3335 | tracing_stop_cmdline_record(); | |
07d777fe SR |
3336 | } |
3337 | ||
769b0441 | 3338 | /** |
48ead020 | 3339 | * trace_vbprintk - write binary msg to tracing buffer |
c68c9ec1 JK |
3340 | * @ip: The address of the caller |
3341 | * @fmt: The string format to write to the buffer | |
3342 | * @args: Arguments for @fmt | |
769b0441 | 3343 | */ |
40ce74f1 | 3344 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 3345 | { |
2425bcb9 | 3346 | struct trace_event_call *call = &event_bprint; |
769b0441 | 3347 | struct ring_buffer_event *event; |
13292494 | 3348 | struct trace_buffer *buffer; |
769b0441 | 3349 | struct trace_array *tr = &global_trace; |
48ead020 | 3350 | struct bprint_entry *entry; |
36590c50 | 3351 | unsigned int trace_ctx; |
07d777fe | 3352 | char *tbuffer; |
36590c50 | 3353 | int len = 0, size; |
769b0441 FW |
3354 | |
3355 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
3356 | return 0; | |
3357 | ||
3358 | /* Don't pollute graph traces with trace_vprintk internals */ | |
3359 | pause_graph_tracing(); | |
3360 | ||
36590c50 | 3361 | trace_ctx = tracing_gen_ctx(); |
5168ae50 | 3362 | preempt_disable_notrace(); |
769b0441 | 3363 | |
07d777fe SR |
3364 | tbuffer = get_trace_buf(); |
3365 | if (!tbuffer) { | |
3366 | len = 0; | |
e2ace001 | 3367 | goto out_nobuffer; |
07d777fe | 3368 | } |
769b0441 | 3369 | |
07d777fe | 3370 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 3371 | |
07d777fe | 3372 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
34423f25 | 3373 | goto out_put; |
769b0441 FW |
3374 | |
3375 | size = sizeof(*entry) + sizeof(u32) * len; | |
1c5eb448 | 3376 | buffer = tr->array_buffer.buffer; |
82d1b815 | 3377 | ring_buffer_nest_start(buffer); |
3e9a8aad | 3378 | event = __trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
36590c50 | 3379 | trace_ctx); |
769b0441 | 3380 | if (!event) |
07d777fe | 3381 | goto out; |
769b0441 FW |
3382 | entry = ring_buffer_event_data(event); |
3383 | entry->ip = ip; | |
769b0441 FW |
3384 | entry->fmt = fmt; |
3385 | ||
07d777fe | 3386 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
f306cc82 | 3387 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 3388 | __buffer_unlock_commit(buffer, event); |
36590c50 | 3389 | ftrace_trace_stack(tr, buffer, trace_ctx, 6, NULL); |
d931369b | 3390 | } |
769b0441 | 3391 | |
769b0441 | 3392 | out: |
82d1b815 | 3393 | ring_buffer_nest_end(buffer); |
34423f25 | 3394 | out_put: |
e2ace001 AL |
3395 | put_trace_buf(); |
3396 | ||
3397 | out_nobuffer: | |
5168ae50 | 3398 | preempt_enable_notrace(); |
769b0441 FW |
3399 | unpause_graph_tracing(); |
3400 | ||
3401 | return len; | |
3402 | } | |
48ead020 FW |
3403 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
3404 | ||
26b68dd2 | 3405 | __printf(3, 0) |
12883efb | 3406 | static int |
13292494 | 3407 | __trace_array_vprintk(struct trace_buffer *buffer, |
12883efb | 3408 | unsigned long ip, const char *fmt, va_list args) |
48ead020 | 3409 | { |
2425bcb9 | 3410 | struct trace_event_call *call = &event_print; |
48ead020 | 3411 | struct ring_buffer_event *event; |
36590c50 | 3412 | int len = 0, size; |
48ead020 | 3413 | struct print_entry *entry; |
36590c50 | 3414 | unsigned int trace_ctx; |
07d777fe | 3415 | char *tbuffer; |
48ead020 FW |
3416 | |
3417 | if (tracing_disabled || tracing_selftest_running) | |
3418 | return 0; | |
3419 | ||
07d777fe SR |
3420 | /* Don't pollute graph traces with trace_vprintk internals */ |
3421 | pause_graph_tracing(); | |
3422 | ||
36590c50 | 3423 | trace_ctx = tracing_gen_ctx(); |
48ead020 | 3424 | preempt_disable_notrace(); |
48ead020 | 3425 | |
07d777fe SR |
3426 | |
3427 | tbuffer = get_trace_buf(); | |
3428 | if (!tbuffer) { | |
3429 | len = 0; | |
e2ace001 | 3430 | goto out_nobuffer; |
07d777fe | 3431 | } |
48ead020 | 3432 | |
3558a5ac | 3433 | len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
48ead020 FW |
3434 | |
3435 | size = sizeof(*entry) + len + 1; | |
82d1b815 | 3436 | ring_buffer_nest_start(buffer); |
3e9a8aad | 3437 | event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
36590c50 | 3438 | trace_ctx); |
48ead020 | 3439 | if (!event) |
07d777fe | 3440 | goto out; |
48ead020 | 3441 | entry = ring_buffer_event_data(event); |
c13d2f7c | 3442 | entry->ip = ip; |
48ead020 | 3443 | |
3558a5ac | 3444 | memcpy(&entry->buf, tbuffer, len + 1); |
f306cc82 | 3445 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 3446 | __buffer_unlock_commit(buffer, event); |
36590c50 | 3447 | ftrace_trace_stack(&global_trace, buffer, trace_ctx, 6, NULL); |
d931369b | 3448 | } |
e2ace001 AL |
3449 | |
3450 | out: | |
82d1b815 | 3451 | ring_buffer_nest_end(buffer); |
e2ace001 AL |
3452 | put_trace_buf(); |
3453 | ||
3454 | out_nobuffer: | |
48ead020 | 3455 | preempt_enable_notrace(); |
07d777fe | 3456 | unpause_graph_tracing(); |
48ead020 FW |
3457 | |
3458 | return len; | |
3459 | } | |
659372d3 | 3460 | |
26b68dd2 | 3461 | __printf(3, 0) |
12883efb SRRH |
3462 | int trace_array_vprintk(struct trace_array *tr, |
3463 | unsigned long ip, const char *fmt, va_list args) | |
3464 | { | |
1c5eb448 | 3465 | return __trace_array_vprintk(tr->array_buffer.buffer, ip, fmt, args); |
12883efb SRRH |
3466 | } |
3467 | ||
38ce2a9e SRV |
3468 | /** |
3469 | * trace_array_printk - Print a message to a specific instance | |
3470 | * @tr: The instance trace_array descriptor | |
3471 | * @ip: The instruction pointer that this is called from. | |
3472 | * @fmt: The format to print (printf format) | |
3473 | * | |
3474 | * If a subsystem sets up its own instance, they have the right to | |
3475 | * printk strings into their tracing instance buffer using this | |
3476 | * function. Note, this function will not write into the top level | |
3477 | * buffer (use trace_printk() for that), as writing into the top level | |
3478 | * buffer should only have events that can be individually disabled. | |
3479 | * trace_printk() is only used for debugging a kernel, and should not | |
f2cc020d | 3480 | * be ever incorporated in normal use. |
38ce2a9e SRV |
3481 | * |
3482 | * trace_array_printk() can be used, as it will not add noise to the | |
3483 | * top level tracing buffer. | |
3484 | * | |
3485 | * Note, trace_array_init_printk() must be called on @tr before this | |
3486 | * can be used. | |
3487 | */ | |
26b68dd2 | 3488 | __printf(3, 0) |
12883efb SRRH |
3489 | int trace_array_printk(struct trace_array *tr, |
3490 | unsigned long ip, const char *fmt, ...) | |
3491 | { | |
3492 | int ret; | |
3493 | va_list ap; | |
3494 | ||
953ae45a DI |
3495 | if (!tr) |
3496 | return -ENOENT; | |
3497 | ||
c791cc4b SRV |
3498 | /* This is only allowed for created instances */ |
3499 | if (tr == &global_trace) | |
3500 | return 0; | |
3501 | ||
3502 | if (!(tr->trace_flags & TRACE_ITER_PRINTK)) | |
3503 | return 0; | |
3504 | ||
12883efb SRRH |
3505 | va_start(ap, fmt); |
3506 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
3507 | va_end(ap); | |
3508 | return ret; | |
3509 | } | |
f45d1225 | 3510 | EXPORT_SYMBOL_GPL(trace_array_printk); |
12883efb | 3511 | |
38ce2a9e SRV |
3512 | /** |
3513 | * trace_array_init_printk - Initialize buffers for trace_array_printk() | |
3514 | * @tr: The trace array to initialize the buffers for | |
3515 | * | |
3516 | * As trace_array_printk() only writes into instances, they are OK to | |
3517 | * have in the kernel (unlike trace_printk()). This needs to be called | |
3518 | * before trace_array_printk() can be used on a trace_array. | |
3519 | */ | |
3520 | int trace_array_init_printk(struct trace_array *tr) | |
3521 | { | |
3522 | if (!tr) | |
3523 | return -ENOENT; | |
3524 | ||
3525 | /* This is only allowed for created instances */ | |
3526 | if (tr == &global_trace) | |
3527 | return -EINVAL; | |
3528 | ||
3529 | return alloc_percpu_trace_buffer(); | |
3530 | } | |
3531 | EXPORT_SYMBOL_GPL(trace_array_init_printk); | |
3532 | ||
26b68dd2 | 3533 | __printf(3, 4) |
13292494 | 3534 | int trace_array_printk_buf(struct trace_buffer *buffer, |
12883efb SRRH |
3535 | unsigned long ip, const char *fmt, ...) |
3536 | { | |
3537 | int ret; | |
3538 | va_list ap; | |
3539 | ||
983f938a | 3540 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
12883efb SRRH |
3541 | return 0; |
3542 | ||
3543 | va_start(ap, fmt); | |
3544 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
3545 | va_end(ap); | |
3546 | return ret; | |
3547 | } | |
3548 | ||
26b68dd2 | 3549 | __printf(2, 0) |
659372d3 SR |
3550 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
3551 | { | |
a813a159 | 3552 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 3553 | } |
769b0441 FW |
3554 | EXPORT_SYMBOL_GPL(trace_vprintk); |
3555 | ||
e2ac8ef5 | 3556 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 3557 | { |
6d158a81 SR |
3558 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
3559 | ||
5a90f577 | 3560 | iter->idx++; |
6d158a81 | 3561 | if (buf_iter) |
bc1a72af | 3562 | ring_buffer_iter_advance(buf_iter); |
5a90f577 SR |
3563 | } |
3564 | ||
e309b41d | 3565 | static struct trace_entry * |
bc21b478 SR |
3566 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
3567 | unsigned long *lost_events) | |
dd0e545f | 3568 | { |
3928a8a2 | 3569 | struct ring_buffer_event *event; |
6d158a81 | 3570 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 3571 | |
c9b7a4a7 | 3572 | if (buf_iter) { |
d769041f | 3573 | event = ring_buffer_iter_peek(buf_iter, ts); |
c9b7a4a7 SRV |
3574 | if (lost_events) |
3575 | *lost_events = ring_buffer_iter_dropped(buf_iter) ? | |
3576 | (unsigned long)-1 : 0; | |
3577 | } else { | |
1c5eb448 | 3578 | event = ring_buffer_peek(iter->array_buffer->buffer, cpu, ts, |
bc21b478 | 3579 | lost_events); |
c9b7a4a7 | 3580 | } |
d769041f | 3581 | |
4a9bd3f1 SR |
3582 | if (event) { |
3583 | iter->ent_size = ring_buffer_event_length(event); | |
3584 | return ring_buffer_event_data(event); | |
3585 | } | |
3586 | iter->ent_size = 0; | |
3587 | return NULL; | |
dd0e545f | 3588 | } |
d769041f | 3589 | |
dd0e545f | 3590 | static struct trace_entry * |
bc21b478 SR |
3591 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
3592 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 3593 | { |
13292494 | 3594 | struct trace_buffer *buffer = iter->array_buffer->buffer; |
bc0c38d1 | 3595 | struct trace_entry *ent, *next = NULL; |
aa27497c | 3596 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 3597 | int cpu_file = iter->cpu_file; |
3928a8a2 | 3598 | u64 next_ts = 0, ts; |
bc0c38d1 | 3599 | int next_cpu = -1; |
12b5da34 | 3600 | int next_size = 0; |
bc0c38d1 SR |
3601 | int cpu; |
3602 | ||
b04cc6b1 FW |
3603 | /* |
3604 | * If we are in a per_cpu trace file, don't bother by iterating over | |
3605 | * all cpu and peek directly. | |
3606 | */ | |
ae3b5093 | 3607 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
3608 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
3609 | return NULL; | |
bc21b478 | 3610 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
3611 | if (ent_cpu) |
3612 | *ent_cpu = cpu_file; | |
3613 | ||
3614 | return ent; | |
3615 | } | |
3616 | ||
ab46428c | 3617 | for_each_tracing_cpu(cpu) { |
dd0e545f | 3618 | |
3928a8a2 SR |
3619 | if (ring_buffer_empty_cpu(buffer, cpu)) |
3620 | continue; | |
dd0e545f | 3621 | |
bc21b478 | 3622 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 3623 | |
cdd31cd2 IM |
3624 | /* |
3625 | * Pick the entry with the smallest timestamp: | |
3626 | */ | |
3928a8a2 | 3627 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
3628 | next = ent; |
3629 | next_cpu = cpu; | |
3928a8a2 | 3630 | next_ts = ts; |
bc21b478 | 3631 | next_lost = lost_events; |
12b5da34 | 3632 | next_size = iter->ent_size; |
bc0c38d1 SR |
3633 | } |
3634 | } | |
3635 | ||
12b5da34 SR |
3636 | iter->ent_size = next_size; |
3637 | ||
bc0c38d1 SR |
3638 | if (ent_cpu) |
3639 | *ent_cpu = next_cpu; | |
3640 | ||
3928a8a2 SR |
3641 | if (ent_ts) |
3642 | *ent_ts = next_ts; | |
3643 | ||
bc21b478 SR |
3644 | if (missing_events) |
3645 | *missing_events = next_lost; | |
3646 | ||
bc0c38d1 SR |
3647 | return next; |
3648 | } | |
3649 | ||
efbbdaa2 MH |
3650 | #define STATIC_FMT_BUF_SIZE 128 |
3651 | static char static_fmt_buf[STATIC_FMT_BUF_SIZE]; | |
3652 | ||
3653 | static char *trace_iter_expand_format(struct trace_iterator *iter) | |
3654 | { | |
3655 | char *tmp; | |
3656 | ||
0e1e71d3 SRV |
3657 | /* |
3658 | * iter->tr is NULL when used with tp_printk, which makes | |
3659 | * this get called where it is not safe to call krealloc(). | |
3660 | */ | |
3661 | if (!iter->tr || iter->fmt == static_fmt_buf) | |
efbbdaa2 MH |
3662 | return NULL; |
3663 | ||
3664 | tmp = krealloc(iter->fmt, iter->fmt_size + STATIC_FMT_BUF_SIZE, | |
3665 | GFP_KERNEL); | |
3666 | if (tmp) { | |
3667 | iter->fmt_size += STATIC_FMT_BUF_SIZE; | |
3668 | iter->fmt = tmp; | |
3669 | } | |
3670 | ||
3671 | return tmp; | |
3672 | } | |
3673 | ||
9a6944fe SRV |
3674 | /* Returns true if the string is safe to dereference from an event */ |
3675 | static bool trace_safe_str(struct trace_iterator *iter, const char *str) | |
3676 | { | |
3677 | unsigned long addr = (unsigned long)str; | |
3678 | struct trace_event *trace_event; | |
3679 | struct trace_event_call *event; | |
3680 | ||
3681 | /* OK if part of the event data */ | |
3682 | if ((addr >= (unsigned long)iter->ent) && | |
3683 | (addr < (unsigned long)iter->ent + iter->ent_size)) | |
3684 | return true; | |
3685 | ||
3686 | /* OK if part of the temp seq buffer */ | |
3687 | if ((addr >= (unsigned long)iter->tmp_seq.buffer) && | |
3688 | (addr < (unsigned long)iter->tmp_seq.buffer + PAGE_SIZE)) | |
3689 | return true; | |
3690 | ||
3691 | /* Core rodata can not be freed */ | |
3692 | if (is_kernel_rodata(addr)) | |
3693 | return true; | |
3694 | ||
3695 | if (trace_is_tracepoint_string(str)) | |
3696 | return true; | |
3697 | ||
3698 | /* | |
3699 | * Now this could be a module event, referencing core module | |
3700 | * data, which is OK. | |
3701 | */ | |
3702 | if (!iter->ent) | |
3703 | return false; | |
3704 | ||
3705 | trace_event = ftrace_find_event(iter->ent->type); | |
3706 | if (!trace_event) | |
3707 | return false; | |
3708 | ||
3709 | event = container_of(trace_event, struct trace_event_call, event); | |
1d18538e | 3710 | if ((event->flags & TRACE_EVENT_FL_DYNAMIC) || !event->module) |
9a6944fe SRV |
3711 | return false; |
3712 | ||
3713 | /* Would rather have rodata, but this will suffice */ | |
1d18538e | 3714 | if (within_module_core(addr, event->module)) |
9a6944fe SRV |
3715 | return true; |
3716 | ||
3717 | return false; | |
3718 | } | |
3719 | ||
3720 | static const char *show_buffer(struct trace_seq *s) | |
3721 | { | |
3722 | struct seq_buf *seq = &s->seq; | |
3723 | ||
3724 | seq_buf_terminate(seq); | |
3725 | ||
3726 | return seq->buffer; | |
3727 | } | |
3728 | ||
3729 | static DEFINE_STATIC_KEY_FALSE(trace_no_verify); | |
3730 | ||
3731 | static int test_can_verify_check(const char *fmt, ...) | |
3732 | { | |
3733 | char buf[16]; | |
3734 | va_list ap; | |
3735 | int ret; | |
3736 | ||
3737 | /* | |
3738 | * The verifier is dependent on vsnprintf() modifies the va_list | |
3739 | * passed to it, where it is sent as a reference. Some architectures | |
3740 | * (like x86_32) passes it by value, which means that vsnprintf() | |
3741 | * does not modify the va_list passed to it, and the verifier | |
3742 | * would then need to be able to understand all the values that | |
3743 | * vsnprintf can use. If it is passed by value, then the verifier | |
3744 | * is disabled. | |
3745 | */ | |
3746 | va_start(ap, fmt); | |
3747 | vsnprintf(buf, 16, "%d", ap); | |
3748 | ret = va_arg(ap, int); | |
3749 | va_end(ap); | |
3750 | ||
3751 | return ret; | |
3752 | } | |
3753 | ||
3754 | static void test_can_verify(void) | |
3755 | { | |
3756 | if (!test_can_verify_check("%d %d", 0, 1)) { | |
3757 | pr_info("trace event string verifier disabled\n"); | |
3758 | static_branch_inc(&trace_no_verify); | |
3759 | } | |
3760 | } | |
3761 | ||
3762 | /** | |
3763 | * trace_check_vprintf - Check dereferenced strings while writing to the seq buffer | |
3764 | * @iter: The iterator that holds the seq buffer and the event being printed | |
3765 | * @fmt: The format used to print the event | |
3766 | * @ap: The va_list holding the data to print from @fmt. | |
3767 | * | |
3768 | * This writes the data into the @iter->seq buffer using the data from | |
3769 | * @fmt and @ap. If the format has a %s, then the source of the string | |
3770 | * is examined to make sure it is safe to print, otherwise it will | |
3771 | * warn and print "[UNSAFE MEMORY]" in place of the dereferenced string | |
3772 | * pointer. | |
3773 | */ | |
3774 | void trace_check_vprintf(struct trace_iterator *iter, const char *fmt, | |
3775 | va_list ap) | |
3776 | { | |
3777 | const char *p = fmt; | |
3778 | const char *str; | |
3779 | int i, j; | |
3780 | ||
3781 | if (WARN_ON_ONCE(!fmt)) | |
3782 | return; | |
3783 | ||
3784 | if (static_branch_unlikely(&trace_no_verify)) | |
3785 | goto print; | |
3786 | ||
3787 | /* Don't bother checking when doing a ftrace_dump() */ | |
3788 | if (iter->fmt == static_fmt_buf) | |
3789 | goto print; | |
3790 | ||
3791 | while (*p) { | |
eb01f535 SRV |
3792 | bool star = false; |
3793 | int len = 0; | |
3794 | ||
9a6944fe SRV |
3795 | j = 0; |
3796 | ||
3797 | /* We only care about %s and variants */ | |
3798 | for (i = 0; p[i]; i++) { | |
3799 | if (i + 1 >= iter->fmt_size) { | |
3800 | /* | |
3801 | * If we can't expand the copy buffer, | |
3802 | * just print it. | |
3803 | */ | |
3804 | if (!trace_iter_expand_format(iter)) | |
3805 | goto print; | |
3806 | } | |
3807 | ||
3808 | if (p[i] == '\\' && p[i+1]) { | |
3809 | i++; | |
3810 | continue; | |
3811 | } | |
3812 | if (p[i] == '%') { | |
3813 | /* Need to test cases like %08.*s */ | |
3814 | for (j = 1; p[i+j]; j++) { | |
3815 | if (isdigit(p[i+j]) || | |
9a6944fe SRV |
3816 | p[i+j] == '.') |
3817 | continue; | |
eb01f535 SRV |
3818 | if (p[i+j] == '*') { |
3819 | star = true; | |
3820 | continue; | |
3821 | } | |
9a6944fe SRV |
3822 | break; |
3823 | } | |
3824 | if (p[i+j] == 's') | |
3825 | break; | |
eb01f535 | 3826 | star = false; |
9a6944fe SRV |
3827 | } |
3828 | j = 0; | |
3829 | } | |
3830 | /* If no %s found then just print normally */ | |
3831 | if (!p[i]) | |
3832 | break; | |
3833 | ||
3834 | /* Copy up to the %s, and print that */ | |
3835 | strncpy(iter->fmt, p, i); | |
3836 | iter->fmt[i] = '\0'; | |
3837 | trace_seq_vprintf(&iter->seq, iter->fmt, ap); | |
3838 | ||
eb01f535 SRV |
3839 | if (star) |
3840 | len = va_arg(ap, int); | |
3841 | ||
9a6944fe SRV |
3842 | /* The ap now points to the string data of the %s */ |
3843 | str = va_arg(ap, const char *); | |
3844 | ||
3845 | /* | |
3846 | * If you hit this warning, it is likely that the | |
3847 | * trace event in question used %s on a string that | |
3848 | * was saved at the time of the event, but may not be | |
3849 | * around when the trace is read. Use __string(), | |
3850 | * __assign_str() and __get_str() helpers in the TRACE_EVENT() | |
3851 | * instead. See samples/trace_events/trace-events-sample.h | |
3852 | * for reference. | |
3853 | */ | |
3854 | if (WARN_ONCE(!trace_safe_str(iter, str), | |
3855 | "fmt: '%s' current_buffer: '%s'", | |
3856 | fmt, show_buffer(&iter->seq))) { | |
3857 | int ret; | |
3858 | ||
3859 | /* Try to safely read the string */ | |
eb01f535 SRV |
3860 | if (star) { |
3861 | if (len + 1 > iter->fmt_size) | |
3862 | len = iter->fmt_size - 1; | |
3863 | if (len < 0) | |
3864 | len = 0; | |
3865 | ret = copy_from_kernel_nofault(iter->fmt, str, len); | |
3866 | iter->fmt[len] = 0; | |
3867 | star = false; | |
3868 | } else { | |
3869 | ret = strncpy_from_kernel_nofault(iter->fmt, str, | |
3870 | iter->fmt_size); | |
3871 | } | |
9a6944fe SRV |
3872 | if (ret < 0) |
3873 | trace_seq_printf(&iter->seq, "(0x%px)", str); | |
3874 | else | |
3875 | trace_seq_printf(&iter->seq, "(0x%px:%s)", | |
3876 | str, iter->fmt); | |
3877 | str = "[UNSAFE-MEMORY]"; | |
3878 | strcpy(iter->fmt, "%s"); | |
3879 | } else { | |
3880 | strncpy(iter->fmt, p + i, j + 1); | |
3881 | iter->fmt[j+1] = '\0'; | |
3882 | } | |
eb01f535 SRV |
3883 | if (star) |
3884 | trace_seq_printf(&iter->seq, iter->fmt, len, str); | |
3885 | else | |
3886 | trace_seq_printf(&iter->seq, iter->fmt, str); | |
9a6944fe SRV |
3887 | |
3888 | p += i + j + 1; | |
3889 | } | |
3890 | print: | |
3891 | if (*p) | |
3892 | trace_seq_vprintf(&iter->seq, p, ap); | |
3893 | } | |
3894 | ||
efbbdaa2 MH |
3895 | const char *trace_event_format(struct trace_iterator *iter, const char *fmt) |
3896 | { | |
3897 | const char *p, *new_fmt; | |
3898 | char *q; | |
3899 | ||
3900 | if (WARN_ON_ONCE(!fmt)) | |
3901 | return fmt; | |
3902 | ||
0e1e71d3 | 3903 | if (!iter->tr || iter->tr->trace_flags & TRACE_ITER_HASH_PTR) |
a345a671 MH |
3904 | return fmt; |
3905 | ||
efbbdaa2 MH |
3906 | p = fmt; |
3907 | new_fmt = q = iter->fmt; | |
3908 | while (*p) { | |
3909 | if (unlikely(q - new_fmt + 3 > iter->fmt_size)) { | |
3910 | if (!trace_iter_expand_format(iter)) | |
3911 | return fmt; | |
3912 | ||
3913 | q += iter->fmt - new_fmt; | |
3914 | new_fmt = iter->fmt; | |
3915 | } | |
3916 | ||
3917 | *q++ = *p++; | |
3918 | ||
3919 | /* Replace %p with %px */ | |
3920 | if (p[-1] == '%') { | |
3921 | if (p[0] == '%') { | |
3922 | *q++ = *p++; | |
3923 | } else if (p[0] == 'p' && !isalnum(p[1])) { | |
3924 | *q++ = *p++; | |
3925 | *q++ = 'x'; | |
3926 | } | |
3927 | } | |
3928 | } | |
3929 | *q = '\0'; | |
3930 | ||
3931 | return new_fmt; | |
3932 | } | |
3933 | ||
8e99cf91 | 3934 | #define STATIC_TEMP_BUF_SIZE 128 |
8fa655a3 | 3935 | static char static_temp_buf[STATIC_TEMP_BUF_SIZE] __aligned(4); |
8e99cf91 | 3936 | |
dd0e545f | 3937 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
3938 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
3939 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 3940 | { |
ff895103 SRV |
3941 | /* __find_next_entry will reset ent_size */ |
3942 | int ent_size = iter->ent_size; | |
3943 | struct trace_entry *entry; | |
3944 | ||
8e99cf91 SRV |
3945 | /* |
3946 | * If called from ftrace_dump(), then the iter->temp buffer | |
3947 | * will be the static_temp_buf and not created from kmalloc. | |
3948 | * If the entry size is greater than the buffer, we can | |
3949 | * not save it. Just return NULL in that case. This is only | |
3950 | * used to add markers when two consecutive events' time | |
3951 | * stamps have a large delta. See trace_print_lat_context() | |
3952 | */ | |
3953 | if (iter->temp == static_temp_buf && | |
3954 | STATIC_TEMP_BUF_SIZE < ent_size) | |
3955 | return NULL; | |
3956 | ||
ff895103 SRV |
3957 | /* |
3958 | * The __find_next_entry() may call peek_next_entry(), which may | |
3959 | * call ring_buffer_peek() that may make the contents of iter->ent | |
3960 | * undefined. Need to copy iter->ent now. | |
3961 | */ | |
3962 | if (iter->ent && iter->ent != iter->temp) { | |
8e99cf91 SRV |
3963 | if ((!iter->temp || iter->temp_size < iter->ent_size) && |
3964 | !WARN_ON_ONCE(iter->temp == static_temp_buf)) { | |
851e6f61 SRV |
3965 | void *temp; |
3966 | temp = kmalloc(iter->ent_size, GFP_KERNEL); | |
3967 | if (!temp) | |
ff895103 | 3968 | return NULL; |
851e6f61 SRV |
3969 | kfree(iter->temp); |
3970 | iter->temp = temp; | |
3971 | iter->temp_size = iter->ent_size; | |
ff895103 SRV |
3972 | } |
3973 | memcpy(iter->temp, iter->ent, iter->ent_size); | |
ff895103 SRV |
3974 | iter->ent = iter->temp; |
3975 | } | |
3976 | entry = __find_next_entry(iter, ent_cpu, NULL, ent_ts); | |
3977 | /* Put back the original ent_size */ | |
3978 | iter->ent_size = ent_size; | |
3979 | ||
3980 | return entry; | |
dd0e545f SR |
3981 | } |
3982 | ||
3983 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 3984 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 3985 | { |
bc21b478 SR |
3986 | iter->ent = __find_next_entry(iter, &iter->cpu, |
3987 | &iter->lost_events, &iter->ts); | |
dd0e545f | 3988 | |
3928a8a2 | 3989 | if (iter->ent) |
e2ac8ef5 | 3990 | trace_iterator_increment(iter); |
dd0e545f | 3991 | |
3928a8a2 | 3992 | return iter->ent ? iter : NULL; |
b3806b43 | 3993 | } |
bc0c38d1 | 3994 | |
e309b41d | 3995 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 3996 | { |
1c5eb448 | 3997 | ring_buffer_consume(iter->array_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 3998 | &iter->lost_events); |
bc0c38d1 SR |
3999 | } |
4000 | ||
e309b41d | 4001 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
4002 | { |
4003 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 4004 | int i = (int)*pos; |
4e3c3333 | 4005 | void *ent; |
bc0c38d1 | 4006 | |
a63ce5b3 SR |
4007 | WARN_ON_ONCE(iter->leftover); |
4008 | ||
bc0c38d1 SR |
4009 | (*pos)++; |
4010 | ||
4011 | /* can't go backwards */ | |
4012 | if (iter->idx > i) | |
4013 | return NULL; | |
4014 | ||
4015 | if (iter->idx < 0) | |
955b61e5 | 4016 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
4017 | else |
4018 | ent = iter; | |
4019 | ||
4020 | while (ent && iter->idx < i) | |
955b61e5 | 4021 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
4022 | |
4023 | iter->pos = *pos; | |
4024 | ||
bc0c38d1 SR |
4025 | return ent; |
4026 | } | |
4027 | ||
955b61e5 | 4028 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 4029 | { |
2f26ebd5 SR |
4030 | struct ring_buffer_iter *buf_iter; |
4031 | unsigned long entries = 0; | |
4032 | u64 ts; | |
4033 | ||
1c5eb448 | 4034 | per_cpu_ptr(iter->array_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 4035 | |
6d158a81 SR |
4036 | buf_iter = trace_buffer_iter(iter, cpu); |
4037 | if (!buf_iter) | |
2f26ebd5 SR |
4038 | return; |
4039 | ||
2f26ebd5 SR |
4040 | ring_buffer_iter_reset(buf_iter); |
4041 | ||
4042 | /* | |
4043 | * We could have the case with the max latency tracers | |
4044 | * that a reset never took place on a cpu. This is evident | |
4045 | * by the timestamp being before the start of the buffer. | |
4046 | */ | |
69243720 | 4047 | while (ring_buffer_iter_peek(buf_iter, &ts)) { |
1c5eb448 | 4048 | if (ts >= iter->array_buffer->time_start) |
2f26ebd5 SR |
4049 | break; |
4050 | entries++; | |
bc1a72af | 4051 | ring_buffer_iter_advance(buf_iter); |
2f26ebd5 SR |
4052 | } |
4053 | ||
1c5eb448 | 4054 | per_cpu_ptr(iter->array_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
4055 | } |
4056 | ||
d7350c3f | 4057 | /* |
d7350c3f FW |
4058 | * The current tracer is copied to avoid a global locking |
4059 | * all around. | |
4060 | */ | |
bc0c38d1 SR |
4061 | static void *s_start(struct seq_file *m, loff_t *pos) |
4062 | { | |
4063 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 4064 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 4065 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
4066 | void *p = NULL; |
4067 | loff_t l = 0; | |
3928a8a2 | 4068 | int cpu; |
bc0c38d1 | 4069 | |
2fd196ec HT |
4070 | /* |
4071 | * copy the tracer to avoid using a global lock all around. | |
4072 | * iter->trace is a copy of current_trace, the pointer to the | |
4073 | * name may be used instead of a strcmp(), as iter->trace->name | |
4074 | * will point to the same string as current_trace->name. | |
4075 | */ | |
bc0c38d1 | 4076 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4077 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
4078 | *iter->trace = *tr->current_trace; | |
d7350c3f | 4079 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 4080 | |
12883efb | 4081 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
4082 | if (iter->snapshot && iter->trace->use_max_tr) |
4083 | return ERR_PTR(-EBUSY); | |
12883efb | 4084 | #endif |
debdd57f | 4085 | |
bc0c38d1 SR |
4086 | if (*pos != iter->pos) { |
4087 | iter->ent = NULL; | |
4088 | iter->cpu = 0; | |
4089 | iter->idx = -1; | |
4090 | ||
ae3b5093 | 4091 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 4092 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 4093 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 4094 | } else |
2f26ebd5 | 4095 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 4096 | |
ac91d854 | 4097 | iter->leftover = 0; |
bc0c38d1 SR |
4098 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
4099 | ; | |
4100 | ||
4101 | } else { | |
a63ce5b3 SR |
4102 | /* |
4103 | * If we overflowed the seq_file before, then we want | |
4104 | * to just reuse the trace_seq buffer again. | |
4105 | */ | |
4106 | if (iter->leftover) | |
4107 | p = iter; | |
4108 | else { | |
4109 | l = *pos - 1; | |
4110 | p = s_next(m, p, &l); | |
4111 | } | |
bc0c38d1 SR |
4112 | } |
4113 | ||
4f535968 | 4114 | trace_event_read_lock(); |
7e53bd42 | 4115 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
4116 | return p; |
4117 | } | |
4118 | ||
4119 | static void s_stop(struct seq_file *m, void *p) | |
4120 | { | |
7e53bd42 LJ |
4121 | struct trace_iterator *iter = m->private; |
4122 | ||
12883efb | 4123 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
4124 | if (iter->snapshot && iter->trace->use_max_tr) |
4125 | return; | |
12883efb | 4126 | #endif |
debdd57f | 4127 | |
7e53bd42 | 4128 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4129 | trace_event_read_unlock(); |
bc0c38d1 SR |
4130 | } |
4131 | ||
ecffc8a8 | 4132 | static void |
1c5eb448 | 4133 | get_total_entries_cpu(struct array_buffer *buf, unsigned long *total, |
ecffc8a8 DA |
4134 | unsigned long *entries, int cpu) |
4135 | { | |
4136 | unsigned long count; | |
4137 | ||
4138 | count = ring_buffer_entries_cpu(buf->buffer, cpu); | |
4139 | /* | |
4140 | * If this buffer has skipped entries, then we hold all | |
4141 | * entries for the trace and we need to ignore the | |
4142 | * ones before the time stamp. | |
4143 | */ | |
4144 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { | |
4145 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
4146 | /* total is the same as the entries */ | |
4147 | *total = count; | |
4148 | } else | |
4149 | *total = count + | |
4150 | ring_buffer_overrun_cpu(buf->buffer, cpu); | |
4151 | *entries = count; | |
4152 | } | |
4153 | ||
39eaf7ef | 4154 | static void |
1c5eb448 | 4155 | get_total_entries(struct array_buffer *buf, |
12883efb | 4156 | unsigned long *total, unsigned long *entries) |
39eaf7ef | 4157 | { |
ecffc8a8 | 4158 | unsigned long t, e; |
39eaf7ef SR |
4159 | int cpu; |
4160 | ||
4161 | *total = 0; | |
4162 | *entries = 0; | |
4163 | ||
4164 | for_each_tracing_cpu(cpu) { | |
ecffc8a8 DA |
4165 | get_total_entries_cpu(buf, &t, &e, cpu); |
4166 | *total += t; | |
4167 | *entries += e; | |
39eaf7ef SR |
4168 | } |
4169 | } | |
4170 | ||
ecffc8a8 DA |
4171 | unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu) |
4172 | { | |
4173 | unsigned long total, entries; | |
4174 | ||
4175 | if (!tr) | |
4176 | tr = &global_trace; | |
4177 | ||
1c5eb448 | 4178 | get_total_entries_cpu(&tr->array_buffer, &total, &entries, cpu); |
ecffc8a8 DA |
4179 | |
4180 | return entries; | |
4181 | } | |
4182 | ||
4183 | unsigned long trace_total_entries(struct trace_array *tr) | |
4184 | { | |
4185 | unsigned long total, entries; | |
4186 | ||
4187 | if (!tr) | |
4188 | tr = &global_trace; | |
4189 | ||
1c5eb448 | 4190 | get_total_entries(&tr->array_buffer, &total, &entries); |
ecffc8a8 DA |
4191 | |
4192 | return entries; | |
4193 | } | |
4194 | ||
e309b41d | 4195 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 4196 | { |
795d6379 SAS |
4197 | seq_puts(m, "# _------=> CPU# \n" |
4198 | "# / _-----=> irqs-off \n" | |
4199 | "# | / _----=> need-resched \n" | |
4200 | "# || / _---=> hardirq/softirq \n" | |
4201 | "# ||| / _--=> preempt-depth \n" | |
54357f0c TG |
4202 | "# |||| / _-=> migrate-disable \n" |
4203 | "# ||||| / delay \n" | |
4204 | "# cmd pid |||||| time | caller \n" | |
4205 | "# \\ / |||||| \\ | / \n"); | |
bc0c38d1 SR |
4206 | } |
4207 | ||
1c5eb448 | 4208 | static void print_event_info(struct array_buffer *buf, struct seq_file *m) |
bc0c38d1 | 4209 | { |
39eaf7ef SR |
4210 | unsigned long total; |
4211 | unsigned long entries; | |
4212 | ||
12883efb | 4213 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
4214 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
4215 | entries, total, num_online_cpus()); | |
4216 | seq_puts(m, "#\n"); | |
4217 | } | |
4218 | ||
1c5eb448 | 4219 | static void print_func_help_header(struct array_buffer *buf, struct seq_file *m, |
441dae8f | 4220 | unsigned int flags) |
39eaf7ef | 4221 | { |
441dae8f JF |
4222 | bool tgid = flags & TRACE_ITER_RECORD_TGID; |
4223 | ||
12883efb | 4224 | print_event_info(buf, m); |
441dae8f | 4225 | |
795d6379 SAS |
4226 | seq_printf(m, "# TASK-PID %s CPU# TIMESTAMP FUNCTION\n", tgid ? " TGID " : ""); |
4227 | seq_printf(m, "# | | %s | | |\n", tgid ? " | " : ""); | |
bc0c38d1 SR |
4228 | } |
4229 | ||
1c5eb448 | 4230 | static void print_func_help_header_irq(struct array_buffer *buf, struct seq_file *m, |
441dae8f | 4231 | unsigned int flags) |
77271ce4 | 4232 | { |
441dae8f | 4233 | bool tgid = flags & TRACE_ITER_RECORD_TGID; |
795d6379 SAS |
4234 | const char *space = " "; |
4235 | int prec = tgid ? 12 : 2; | |
b11fb737 | 4236 | |
9e738215 QP |
4237 | print_event_info(buf, m); |
4238 | ||
795d6379 SAS |
4239 | seq_printf(m, "# %.*s _-----=> irqs-off\n", prec, space); |
4240 | seq_printf(m, "# %.*s / _----=> need-resched\n", prec, space); | |
4241 | seq_printf(m, "# %.*s| / _---=> hardirq/softirq\n", prec, space); | |
4242 | seq_printf(m, "# %.*s|| / _--=> preempt-depth\n", prec, space); | |
54357f0c TG |
4243 | seq_printf(m, "# %.*s||| / _-=> migrate-disable\n", prec, space); |
4244 | seq_printf(m, "# %.*s|||| / delay\n", prec, space); | |
4245 | seq_printf(m, "# TASK-PID %.*s CPU# ||||| TIMESTAMP FUNCTION\n", prec, " TGID "); | |
4246 | seq_printf(m, "# | | %.*s | ||||| | |\n", prec, " | "); | |
77271ce4 | 4247 | } |
bc0c38d1 | 4248 | |
62b915f1 | 4249 | void |
bc0c38d1 SR |
4250 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
4251 | { | |
983f938a | 4252 | unsigned long sym_flags = (global_trace.trace_flags & TRACE_ITER_SYM_MASK); |
1c5eb448 | 4253 | struct array_buffer *buf = iter->array_buffer; |
12883efb | 4254 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); |
2b6080f2 | 4255 | struct tracer *type = iter->trace; |
39eaf7ef SR |
4256 | unsigned long entries; |
4257 | unsigned long total; | |
bc0c38d1 SR |
4258 | const char *name = "preemption"; |
4259 | ||
d840f718 | 4260 | name = type->name; |
bc0c38d1 | 4261 | |
12883efb | 4262 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 4263 | |
888b55dc | 4264 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 4265 | name, UTS_RELEASE); |
888b55dc | 4266 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 4267 | "---------------------------------\n"); |
888b55dc | 4268 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 4269 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 4270 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 4271 | entries, |
4c11d7ae | 4272 | total, |
12883efb | 4273 | buf->cpu, |
bc0c38d1 SR |
4274 | #if defined(CONFIG_PREEMPT_NONE) |
4275 | "server", | |
4276 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
4277 | "desktop", | |
b5c21b45 | 4278 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 | 4279 | "preempt", |
9c34fc4b SAS |
4280 | #elif defined(CONFIG_PREEMPT_RT) |
4281 | "preempt_rt", | |
bc0c38d1 SR |
4282 | #else |
4283 | "unknown", | |
4284 | #endif | |
4285 | /* These are reserved for later use */ | |
4286 | 0, 0, 0, 0); | |
4287 | #ifdef CONFIG_SMP | |
4288 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
4289 | #else | |
4290 | seq_puts(m, ")\n"); | |
4291 | #endif | |
888b55dc KM |
4292 | seq_puts(m, "# -----------------\n"); |
4293 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 4294 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
4295 | data->comm, data->pid, |
4296 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 4297 | data->policy, data->rt_priority); |
888b55dc | 4298 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
4299 | |
4300 | if (data->critical_start) { | |
888b55dc | 4301 | seq_puts(m, "# => started at: "); |
214023c3 SR |
4302 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
4303 | trace_print_seq(m, &iter->seq); | |
888b55dc | 4304 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
4305 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
4306 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 4307 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
4308 | } |
4309 | ||
888b55dc | 4310 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
4311 | } |
4312 | ||
a309720c SR |
4313 | static void test_cpu_buff_start(struct trace_iterator *iter) |
4314 | { | |
4315 | struct trace_seq *s = &iter->seq; | |
983f938a | 4316 | struct trace_array *tr = iter->tr; |
a309720c | 4317 | |
983f938a | 4318 | if (!(tr->trace_flags & TRACE_ITER_ANNOTATE)) |
12ef7d44 SR |
4319 | return; |
4320 | ||
4321 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
4322 | return; | |
4323 | ||
4dbbe2d8 MK |
4324 | if (cpumask_available(iter->started) && |
4325 | cpumask_test_cpu(iter->cpu, iter->started)) | |
a309720c SR |
4326 | return; |
4327 | ||
1c5eb448 | 4328 | if (per_cpu_ptr(iter->array_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
4329 | return; |
4330 | ||
4dbbe2d8 | 4331 | if (cpumask_available(iter->started)) |
919cd979 | 4332 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
4333 | |
4334 | /* Don't print started cpu buffer for the first entry of the trace */ | |
4335 | if (iter->idx > 1) | |
4336 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
4337 | iter->cpu); | |
a309720c SR |
4338 | } |
4339 | ||
2c4f035f | 4340 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 4341 | { |
983f938a | 4342 | struct trace_array *tr = iter->tr; |
214023c3 | 4343 | struct trace_seq *s = &iter->seq; |
983f938a | 4344 | unsigned long sym_flags = (tr->trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 4345 | struct trace_entry *entry; |
f633cef0 | 4346 | struct trace_event *event; |
bc0c38d1 | 4347 | |
4e3c3333 | 4348 | entry = iter->ent; |
dd0e545f | 4349 | |
a309720c SR |
4350 | test_cpu_buff_start(iter); |
4351 | ||
c4a8e8be | 4352 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 4353 | |
983f938a | 4354 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
4355 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) |
4356 | trace_print_lat_context(iter); | |
4357 | else | |
4358 | trace_print_context(iter); | |
c4a8e8be | 4359 | } |
bc0c38d1 | 4360 | |
19a7fe20 SRRH |
4361 | if (trace_seq_has_overflowed(s)) |
4362 | return TRACE_TYPE_PARTIAL_LINE; | |
4363 | ||
268ccda0 | 4364 | if (event) |
a9a57763 | 4365 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 | 4366 | |
19a7fe20 | 4367 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
02b67518 | 4368 | |
19a7fe20 | 4369 | return trace_handle_return(s); |
bc0c38d1 SR |
4370 | } |
4371 | ||
2c4f035f | 4372 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 | 4373 | { |
983f938a | 4374 | struct trace_array *tr = iter->tr; |
f9896bf3 IM |
4375 | struct trace_seq *s = &iter->seq; |
4376 | struct trace_entry *entry; | |
f633cef0 | 4377 | struct trace_event *event; |
f9896bf3 IM |
4378 | |
4379 | entry = iter->ent; | |
dd0e545f | 4380 | |
983f938a | 4381 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) |
19a7fe20 SRRH |
4382 | trace_seq_printf(s, "%d %d %llu ", |
4383 | entry->pid, iter->cpu, iter->ts); | |
4384 | ||
4385 | if (trace_seq_has_overflowed(s)) | |
4386 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 | 4387 | |
f633cef0 | 4388 | event = ftrace_find_event(entry->type); |
268ccda0 | 4389 | if (event) |
a9a57763 | 4390 | return event->funcs->raw(iter, 0, event); |
d9793bd8 | 4391 | |
19a7fe20 | 4392 | trace_seq_printf(s, "%d ?\n", entry->type); |
777e208d | 4393 | |
19a7fe20 | 4394 | return trace_handle_return(s); |
f9896bf3 IM |
4395 | } |
4396 | ||
2c4f035f | 4397 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec | 4398 | { |
983f938a | 4399 | struct trace_array *tr = iter->tr; |
5e3ca0ec IM |
4400 | struct trace_seq *s = &iter->seq; |
4401 | unsigned char newline = '\n'; | |
4402 | struct trace_entry *entry; | |
f633cef0 | 4403 | struct trace_event *event; |
5e3ca0ec IM |
4404 | |
4405 | entry = iter->ent; | |
dd0e545f | 4406 | |
983f938a | 4407 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
4408 | SEQ_PUT_HEX_FIELD(s, entry->pid); |
4409 | SEQ_PUT_HEX_FIELD(s, iter->cpu); | |
4410 | SEQ_PUT_HEX_FIELD(s, iter->ts); | |
4411 | if (trace_seq_has_overflowed(s)) | |
4412 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 4413 | } |
5e3ca0ec | 4414 | |
f633cef0 | 4415 | event = ftrace_find_event(entry->type); |
268ccda0 | 4416 | if (event) { |
a9a57763 | 4417 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
4418 | if (ret != TRACE_TYPE_HANDLED) |
4419 | return ret; | |
4420 | } | |
7104f300 | 4421 | |
19a7fe20 | 4422 | SEQ_PUT_FIELD(s, newline); |
5e3ca0ec | 4423 | |
19a7fe20 | 4424 | return trace_handle_return(s); |
5e3ca0ec IM |
4425 | } |
4426 | ||
2c4f035f | 4427 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa | 4428 | { |
983f938a | 4429 | struct trace_array *tr = iter->tr; |
cb0f12aa IM |
4430 | struct trace_seq *s = &iter->seq; |
4431 | struct trace_entry *entry; | |
f633cef0 | 4432 | struct trace_event *event; |
cb0f12aa IM |
4433 | |
4434 | entry = iter->ent; | |
dd0e545f | 4435 | |
983f938a | 4436 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
4437 | SEQ_PUT_FIELD(s, entry->pid); |
4438 | SEQ_PUT_FIELD(s, iter->cpu); | |
4439 | SEQ_PUT_FIELD(s, iter->ts); | |
4440 | if (trace_seq_has_overflowed(s)) | |
4441 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 4442 | } |
cb0f12aa | 4443 | |
f633cef0 | 4444 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
4445 | return event ? event->funcs->binary(iter, 0, event) : |
4446 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
4447 | } |
4448 | ||
62b915f1 | 4449 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 4450 | { |
6d158a81 | 4451 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
4452 | int cpu; |
4453 | ||
9aba60fe | 4454 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 4455 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 4456 | cpu = iter->cpu_file; |
6d158a81 SR |
4457 | buf_iter = trace_buffer_iter(iter, cpu); |
4458 | if (buf_iter) { | |
4459 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
4460 | return 0; |
4461 | } else { | |
1c5eb448 | 4462 | if (!ring_buffer_empty_cpu(iter->array_buffer->buffer, cpu)) |
9aba60fe SR |
4463 | return 0; |
4464 | } | |
4465 | return 1; | |
4466 | } | |
4467 | ||
ab46428c | 4468 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
4469 | buf_iter = trace_buffer_iter(iter, cpu); |
4470 | if (buf_iter) { | |
4471 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
4472 | return 0; |
4473 | } else { | |
1c5eb448 | 4474 | if (!ring_buffer_empty_cpu(iter->array_buffer->buffer, cpu)) |
d769041f SR |
4475 | return 0; |
4476 | } | |
bc0c38d1 | 4477 | } |
d769041f | 4478 | |
797d3712 | 4479 | return 1; |
bc0c38d1 SR |
4480 | } |
4481 | ||
4f535968 | 4482 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 4483 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 4484 | { |
983f938a SRRH |
4485 | struct trace_array *tr = iter->tr; |
4486 | unsigned long trace_flags = tr->trace_flags; | |
2c4f035f FW |
4487 | enum print_line_t ret; |
4488 | ||
19a7fe20 | 4489 | if (iter->lost_events) { |
c9b7a4a7 SRV |
4490 | if (iter->lost_events == (unsigned long)-1) |
4491 | trace_seq_printf(&iter->seq, "CPU:%d [LOST EVENTS]\n", | |
4492 | iter->cpu); | |
4493 | else | |
4494 | trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
4495 | iter->cpu, iter->lost_events); | |
19a7fe20 SRRH |
4496 | if (trace_seq_has_overflowed(&iter->seq)) |
4497 | return TRACE_TYPE_PARTIAL_LINE; | |
4498 | } | |
bc21b478 | 4499 | |
2c4f035f FW |
4500 | if (iter->trace && iter->trace->print_line) { |
4501 | ret = iter->trace->print_line(iter); | |
4502 | if (ret != TRACE_TYPE_UNHANDLED) | |
4503 | return ret; | |
4504 | } | |
72829bc3 | 4505 | |
09ae7234 SRRH |
4506 | if (iter->ent->type == TRACE_BPUTS && |
4507 | trace_flags & TRACE_ITER_PRINTK && | |
4508 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
4509 | return trace_print_bputs_msg_only(iter); | |
4510 | ||
48ead020 FW |
4511 | if (iter->ent->type == TRACE_BPRINT && |
4512 | trace_flags & TRACE_ITER_PRINTK && | |
4513 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 4514 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 4515 | |
66896a85 FW |
4516 | if (iter->ent->type == TRACE_PRINT && |
4517 | trace_flags & TRACE_ITER_PRINTK && | |
4518 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 4519 | return trace_print_printk_msg_only(iter); |
66896a85 | 4520 | |
cb0f12aa IM |
4521 | if (trace_flags & TRACE_ITER_BIN) |
4522 | return print_bin_fmt(iter); | |
4523 | ||
5e3ca0ec IM |
4524 | if (trace_flags & TRACE_ITER_HEX) |
4525 | return print_hex_fmt(iter); | |
4526 | ||
f9896bf3 IM |
4527 | if (trace_flags & TRACE_ITER_RAW) |
4528 | return print_raw_fmt(iter); | |
4529 | ||
f9896bf3 IM |
4530 | return print_trace_fmt(iter); |
4531 | } | |
4532 | ||
7e9a49ef JO |
4533 | void trace_latency_header(struct seq_file *m) |
4534 | { | |
4535 | struct trace_iterator *iter = m->private; | |
983f938a | 4536 | struct trace_array *tr = iter->tr; |
7e9a49ef JO |
4537 | |
4538 | /* print nothing if the buffers are empty */ | |
4539 | if (trace_empty(iter)) | |
4540 | return; | |
4541 | ||
4542 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
4543 | print_trace_header(m, iter); | |
4544 | ||
983f938a | 4545 | if (!(tr->trace_flags & TRACE_ITER_VERBOSE)) |
7e9a49ef JO |
4546 | print_lat_help_header(m); |
4547 | } | |
4548 | ||
62b915f1 JO |
4549 | void trace_default_header(struct seq_file *m) |
4550 | { | |
4551 | struct trace_iterator *iter = m->private; | |
983f938a SRRH |
4552 | struct trace_array *tr = iter->tr; |
4553 | unsigned long trace_flags = tr->trace_flags; | |
62b915f1 | 4554 | |
f56e7f8e JO |
4555 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
4556 | return; | |
4557 | ||
62b915f1 JO |
4558 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
4559 | /* print nothing if the buffers are empty */ | |
4560 | if (trace_empty(iter)) | |
4561 | return; | |
4562 | print_trace_header(m, iter); | |
4563 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
4564 | print_lat_help_header(m); | |
4565 | } else { | |
77271ce4 SR |
4566 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
4567 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
1c5eb448 | 4568 | print_func_help_header_irq(iter->array_buffer, |
441dae8f | 4569 | m, trace_flags); |
77271ce4 | 4570 | else |
1c5eb448 | 4571 | print_func_help_header(iter->array_buffer, m, |
441dae8f | 4572 | trace_flags); |
77271ce4 | 4573 | } |
62b915f1 JO |
4574 | } |
4575 | } | |
4576 | ||
e0a413f6 SR |
4577 | static void test_ftrace_alive(struct seq_file *m) |
4578 | { | |
4579 | if (!ftrace_is_dead()) | |
4580 | return; | |
d79ac28f RV |
4581 | seq_puts(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n" |
4582 | "# MAY BE MISSING FUNCTION EVENTS\n"); | |
e0a413f6 SR |
4583 | } |
4584 | ||
d8741e2e | 4585 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 4586 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 4587 | { |
d79ac28f RV |
4588 | seq_puts(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n" |
4589 | "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" | |
4590 | "# Takes a snapshot of the main buffer.\n" | |
4591 | "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n" | |
4592 | "# (Doesn't have to be '2' works with any number that\n" | |
4593 | "# is not a '0' or '1')\n"); | |
d8741e2e | 4594 | } |
f1affcaa SRRH |
4595 | |
4596 | static void show_snapshot_percpu_help(struct seq_file *m) | |
4597 | { | |
fa6f0cc7 | 4598 | seq_puts(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); |
f1affcaa | 4599 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP |
d79ac28f RV |
4600 | seq_puts(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" |
4601 | "# Takes a snapshot of the main buffer for this cpu.\n"); | |
f1affcaa | 4602 | #else |
d79ac28f RV |
4603 | seq_puts(m, "# echo 1 > snapshot : Not supported with this kernel.\n" |
4604 | "# Must use main snapshot file to allocate.\n"); | |
f1affcaa | 4605 | #endif |
d79ac28f RV |
4606 | seq_puts(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n" |
4607 | "# (Doesn't have to be '2' works with any number that\n" | |
4608 | "# is not a '0' or '1')\n"); | |
f1affcaa SRRH |
4609 | } |
4610 | ||
d8741e2e SRRH |
4611 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
4612 | { | |
45ad21ca | 4613 | if (iter->tr->allocated_snapshot) |
fa6f0cc7 | 4614 | seq_puts(m, "#\n# * Snapshot is allocated *\n#\n"); |
d8741e2e | 4615 | else |
fa6f0cc7 | 4616 | seq_puts(m, "#\n# * Snapshot is freed *\n#\n"); |
d8741e2e | 4617 | |
fa6f0cc7 | 4618 | seq_puts(m, "# Snapshot commands:\n"); |
f1affcaa SRRH |
4619 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
4620 | show_snapshot_main_help(m); | |
4621 | else | |
4622 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
4623 | } |
4624 | #else | |
4625 | /* Should never be called */ | |
4626 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
4627 | #endif | |
4628 | ||
bc0c38d1 SR |
4629 | static int s_show(struct seq_file *m, void *v) |
4630 | { | |
4631 | struct trace_iterator *iter = v; | |
a63ce5b3 | 4632 | int ret; |
bc0c38d1 SR |
4633 | |
4634 | if (iter->ent == NULL) { | |
4635 | if (iter->tr) { | |
4636 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
4637 | seq_puts(m, "#\n"); | |
e0a413f6 | 4638 | test_ftrace_alive(m); |
bc0c38d1 | 4639 | } |
d8741e2e SRRH |
4640 | if (iter->snapshot && trace_empty(iter)) |
4641 | print_snapshot_help(m, iter); | |
4642 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 4643 | iter->trace->print_header(m); |
62b915f1 JO |
4644 | else |
4645 | trace_default_header(m); | |
4646 | ||
a63ce5b3 SR |
4647 | } else if (iter->leftover) { |
4648 | /* | |
4649 | * If we filled the seq_file buffer earlier, we | |
4650 | * want to just show it now. | |
4651 | */ | |
4652 | ret = trace_print_seq(m, &iter->seq); | |
4653 | ||
4654 | /* ret should this time be zero, but you never know */ | |
4655 | iter->leftover = ret; | |
4656 | ||
bc0c38d1 | 4657 | } else { |
f9896bf3 | 4658 | print_trace_line(iter); |
a63ce5b3 SR |
4659 | ret = trace_print_seq(m, &iter->seq); |
4660 | /* | |
4661 | * If we overflow the seq_file buffer, then it will | |
4662 | * ask us for this data again at start up. | |
4663 | * Use that instead. | |
4664 | * ret is 0 if seq_file write succeeded. | |
4665 | * -1 otherwise. | |
4666 | */ | |
4667 | iter->leftover = ret; | |
bc0c38d1 SR |
4668 | } |
4669 | ||
4670 | return 0; | |
4671 | } | |
4672 | ||
649e9c70 ON |
4673 | /* |
4674 | * Should be used after trace_array_get(), trace_types_lock | |
4675 | * ensures that i_cdev was already initialized. | |
4676 | */ | |
4677 | static inline int tracing_get_cpu(struct inode *inode) | |
4678 | { | |
4679 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
4680 | return (long)inode->i_cdev - 1; | |
4681 | return RING_BUFFER_ALL_CPUS; | |
4682 | } | |
4683 | ||
88e9d34c | 4684 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
4685 | .start = s_start, |
4686 | .next = s_next, | |
4687 | .stop = s_stop, | |
4688 | .show = s_show, | |
bc0c38d1 SR |
4689 | }; |
4690 | ||
e309b41d | 4691 | static struct trace_iterator * |
6484c71c | 4692 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 4693 | { |
6484c71c | 4694 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 4695 | struct trace_iterator *iter; |
50e18b94 | 4696 | int cpu; |
bc0c38d1 | 4697 | |
85a2f9b4 SR |
4698 | if (tracing_disabled) |
4699 | return ERR_PTR(-ENODEV); | |
60a11774 | 4700 | |
50e18b94 | 4701 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
4702 | if (!iter) |
4703 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 4704 | |
72917235 | 4705 | iter->buffer_iter = kcalloc(nr_cpu_ids, sizeof(*iter->buffer_iter), |
6d158a81 | 4706 | GFP_KERNEL); |
93574fcc DC |
4707 | if (!iter->buffer_iter) |
4708 | goto release; | |
4709 | ||
ff895103 SRV |
4710 | /* |
4711 | * trace_find_next_entry() may need to save off iter->ent. | |
4712 | * It will place it into the iter->temp buffer. As most | |
4713 | * events are less than 128, allocate a buffer of that size. | |
4714 | * If one is greater, then trace_find_next_entry() will | |
4715 | * allocate a new buffer to adjust for the bigger iter->ent. | |
4716 | * It's not critical if it fails to get allocated here. | |
4717 | */ | |
4718 | iter->temp = kmalloc(128, GFP_KERNEL); | |
4719 | if (iter->temp) | |
4720 | iter->temp_size = 128; | |
4721 | ||
efbbdaa2 MH |
4722 | /* |
4723 | * trace_event_printf() may need to modify given format | |
4724 | * string to replace %p with %px so that it shows real address | |
4725 | * instead of hash value. However, that is only for the event | |
4726 | * tracing, other tracer may not need. Defer the allocation | |
4727 | * until it is needed. | |
4728 | */ | |
4729 | iter->fmt = NULL; | |
4730 | iter->fmt_size = 0; | |
4731 | ||
d7350c3f FW |
4732 | /* |
4733 | * We make a copy of the current tracer to avoid concurrent | |
4734 | * changes on it while we are reading. | |
4735 | */ | |
bc0c38d1 | 4736 | mutex_lock(&trace_types_lock); |
d7350c3f | 4737 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 4738 | if (!iter->trace) |
d7350c3f | 4739 | goto fail; |
85a2f9b4 | 4740 | |
2b6080f2 | 4741 | *iter->trace = *tr->current_trace; |
d7350c3f | 4742 | |
79f55997 | 4743 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
4744 | goto fail; |
4745 | ||
12883efb SRRH |
4746 | iter->tr = tr; |
4747 | ||
4748 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
4749 | /* Currently only the top directory has a snapshot */ |
4750 | if (tr->current_trace->print_max || snapshot) | |
1c5eb448 | 4751 | iter->array_buffer = &tr->max_buffer; |
bc0c38d1 | 4752 | else |
12883efb | 4753 | #endif |
1c5eb448 | 4754 | iter->array_buffer = &tr->array_buffer; |
debdd57f | 4755 | iter->snapshot = snapshot; |
bc0c38d1 | 4756 | iter->pos = -1; |
6484c71c | 4757 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 4758 | mutex_init(&iter->mutex); |
bc0c38d1 | 4759 | |
8bba1bf5 | 4760 | /* Notify the tracer early; before we stop tracing. */ |
b3f7a6cd | 4761 | if (iter->trace->open) |
a93751ca | 4762 | iter->trace->open(iter); |
8bba1bf5 | 4763 | |
12ef7d44 | 4764 | /* Annotate start of buffers if we had overruns */ |
1c5eb448 | 4765 | if (ring_buffer_overruns(iter->array_buffer->buffer)) |
12ef7d44 SR |
4766 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
4767 | ||
8be0709f | 4768 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 4769 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
4770 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
4771 | ||
06e0a548 SRV |
4772 | /* |
4773 | * If pause-on-trace is enabled, then stop the trace while | |
4774 | * dumping, unless this is the "snapshot" file | |
4775 | */ | |
4776 | if (!iter->snapshot && (tr->trace_flags & TRACE_ITER_PAUSE_ON_TRACE)) | |
2b6080f2 | 4777 | tracing_stop_tr(tr); |
2f26ebd5 | 4778 | |
ae3b5093 | 4779 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 4780 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 4781 | iter->buffer_iter[cpu] = |
1c5eb448 | 4782 | ring_buffer_read_prepare(iter->array_buffer->buffer, |
31b265b3 | 4783 | cpu, GFP_KERNEL); |
72c9ddfd DM |
4784 | } |
4785 | ring_buffer_read_prepare_sync(); | |
4786 | for_each_tracing_cpu(cpu) { | |
4787 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 4788 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
4789 | } |
4790 | } else { | |
4791 | cpu = iter->cpu_file; | |
3928a8a2 | 4792 | iter->buffer_iter[cpu] = |
1c5eb448 | 4793 | ring_buffer_read_prepare(iter->array_buffer->buffer, |
31b265b3 | 4794 | cpu, GFP_KERNEL); |
72c9ddfd DM |
4795 | ring_buffer_read_prepare_sync(); |
4796 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 4797 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
4798 | } |
4799 | ||
bc0c38d1 SR |
4800 | mutex_unlock(&trace_types_lock); |
4801 | ||
bc0c38d1 | 4802 | return iter; |
3928a8a2 | 4803 | |
d7350c3f | 4804 | fail: |
3928a8a2 | 4805 | mutex_unlock(&trace_types_lock); |
d7350c3f | 4806 | kfree(iter->trace); |
ff895103 | 4807 | kfree(iter->temp); |
6d158a81 | 4808 | kfree(iter->buffer_iter); |
93574fcc | 4809 | release: |
50e18b94 JO |
4810 | seq_release_private(inode, file); |
4811 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
4812 | } |
4813 | ||
4814 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
4815 | { | |
8530dec6 SRV |
4816 | int ret; |
4817 | ||
4818 | ret = tracing_check_open_get_tr(NULL); | |
4819 | if (ret) | |
4820 | return ret; | |
60a11774 | 4821 | |
bc0c38d1 SR |
4822 | filp->private_data = inode->i_private; |
4823 | return 0; | |
4824 | } | |
4825 | ||
2e86421d GB |
4826 | bool tracing_is_disabled(void) |
4827 | { | |
4828 | return (tracing_disabled) ? true: false; | |
4829 | } | |
4830 | ||
7b85af63 SRRH |
4831 | /* |
4832 | * Open and update trace_array ref count. | |
4833 | * Must have the current trace_array passed to it. | |
4834 | */ | |
aa07d71f | 4835 | int tracing_open_generic_tr(struct inode *inode, struct file *filp) |
7b85af63 SRRH |
4836 | { |
4837 | struct trace_array *tr = inode->i_private; | |
8530dec6 | 4838 | int ret; |
7b85af63 | 4839 | |
8530dec6 SRV |
4840 | ret = tracing_check_open_get_tr(tr); |
4841 | if (ret) | |
4842 | return ret; | |
7b85af63 SRRH |
4843 | |
4844 | filp->private_data = inode->i_private; | |
4845 | ||
4846 | return 0; | |
7b85af63 SRRH |
4847 | } |
4848 | ||
4fd27358 | 4849 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 4850 | { |
6484c71c | 4851 | struct trace_array *tr = inode->i_private; |
907f2784 | 4852 | struct seq_file *m = file->private_data; |
4acd4d00 | 4853 | struct trace_iterator *iter; |
3928a8a2 | 4854 | int cpu; |
bc0c38d1 | 4855 | |
ff451961 | 4856 | if (!(file->f_mode & FMODE_READ)) { |
6484c71c | 4857 | trace_array_put(tr); |
4acd4d00 | 4858 | return 0; |
ff451961 | 4859 | } |
4acd4d00 | 4860 | |
6484c71c | 4861 | /* Writes do not use seq_file */ |
4acd4d00 | 4862 | iter = m->private; |
bc0c38d1 | 4863 | mutex_lock(&trace_types_lock); |
a695cb58 | 4864 | |
3928a8a2 SR |
4865 | for_each_tracing_cpu(cpu) { |
4866 | if (iter->buffer_iter[cpu]) | |
4867 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
4868 | } | |
4869 | ||
bc0c38d1 SR |
4870 | if (iter->trace && iter->trace->close) |
4871 | iter->trace->close(iter); | |
4872 | ||
06e0a548 | 4873 | if (!iter->snapshot && tr->stop_count) |
debdd57f | 4874 | /* reenable tracing if it was previously enabled */ |
2b6080f2 | 4875 | tracing_start_tr(tr); |
f77d09a3 AL |
4876 | |
4877 | __trace_array_put(tr); | |
4878 | ||
bc0c38d1 SR |
4879 | mutex_unlock(&trace_types_lock); |
4880 | ||
d7350c3f | 4881 | mutex_destroy(&iter->mutex); |
b0dfa978 | 4882 | free_cpumask_var(iter->started); |
efbbdaa2 | 4883 | kfree(iter->fmt); |
ff895103 | 4884 | kfree(iter->temp); |
d7350c3f | 4885 | kfree(iter->trace); |
6d158a81 | 4886 | kfree(iter->buffer_iter); |
50e18b94 | 4887 | seq_release_private(inode, file); |
ff451961 | 4888 | |
bc0c38d1 SR |
4889 | return 0; |
4890 | } | |
4891 | ||
7b85af63 SRRH |
4892 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
4893 | { | |
4894 | struct trace_array *tr = inode->i_private; | |
4895 | ||
4896 | trace_array_put(tr); | |
bc0c38d1 SR |
4897 | return 0; |
4898 | } | |
4899 | ||
7b85af63 SRRH |
4900 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
4901 | { | |
4902 | struct trace_array *tr = inode->i_private; | |
4903 | ||
4904 | trace_array_put(tr); | |
4905 | ||
4906 | return single_release(inode, file); | |
4907 | } | |
4908 | ||
bc0c38d1 SR |
4909 | static int tracing_open(struct inode *inode, struct file *file) |
4910 | { | |
6484c71c | 4911 | struct trace_array *tr = inode->i_private; |
85a2f9b4 | 4912 | struct trace_iterator *iter; |
8530dec6 | 4913 | int ret; |
bc0c38d1 | 4914 | |
8530dec6 SRV |
4915 | ret = tracing_check_open_get_tr(tr); |
4916 | if (ret) | |
4917 | return ret; | |
ff451961 | 4918 | |
4acd4d00 | 4919 | /* If this file was open for write, then erase contents */ |
6484c71c ON |
4920 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
4921 | int cpu = tracing_get_cpu(inode); | |
1c5eb448 | 4922 | struct array_buffer *trace_buf = &tr->array_buffer; |
8dd33bcb BY |
4923 | |
4924 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4925 | if (tr->current_trace->print_max) | |
4926 | trace_buf = &tr->max_buffer; | |
4927 | #endif | |
6484c71c ON |
4928 | |
4929 | if (cpu == RING_BUFFER_ALL_CPUS) | |
8dd33bcb | 4930 | tracing_reset_online_cpus(trace_buf); |
4acd4d00 | 4931 | else |
a47b53e9 | 4932 | tracing_reset_cpu(trace_buf, cpu); |
4acd4d00 | 4933 | } |
bc0c38d1 | 4934 | |
4acd4d00 | 4935 | if (file->f_mode & FMODE_READ) { |
6484c71c | 4936 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
4937 | if (IS_ERR(iter)) |
4938 | ret = PTR_ERR(iter); | |
983f938a | 4939 | else if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) |
4acd4d00 SR |
4940 | iter->iter_flags |= TRACE_FILE_LAT_FMT; |
4941 | } | |
ff451961 SRRH |
4942 | |
4943 | if (ret < 0) | |
4944 | trace_array_put(tr); | |
4945 | ||
bc0c38d1 SR |
4946 | return ret; |
4947 | } | |
4948 | ||
607e2ea1 SRRH |
4949 | /* |
4950 | * Some tracers are not suitable for instance buffers. | |
4951 | * A tracer is always available for the global array (toplevel) | |
4952 | * or if it explicitly states that it is. | |
4953 | */ | |
4954 | static bool | |
4955 | trace_ok_for_array(struct tracer *t, struct trace_array *tr) | |
4956 | { | |
4957 | return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; | |
4958 | } | |
4959 | ||
4960 | /* Find the next tracer that this trace array may use */ | |
4961 | static struct tracer * | |
4962 | get_tracer_for_array(struct trace_array *tr, struct tracer *t) | |
4963 | { | |
4964 | while (t && !trace_ok_for_array(t, tr)) | |
4965 | t = t->next; | |
4966 | ||
4967 | return t; | |
4968 | } | |
4969 | ||
e309b41d | 4970 | static void * |
bc0c38d1 SR |
4971 | t_next(struct seq_file *m, void *v, loff_t *pos) |
4972 | { | |
607e2ea1 | 4973 | struct trace_array *tr = m->private; |
f129e965 | 4974 | struct tracer *t = v; |
bc0c38d1 SR |
4975 | |
4976 | (*pos)++; | |
4977 | ||
4978 | if (t) | |
607e2ea1 | 4979 | t = get_tracer_for_array(tr, t->next); |
bc0c38d1 | 4980 | |
bc0c38d1 SR |
4981 | return t; |
4982 | } | |
4983 | ||
4984 | static void *t_start(struct seq_file *m, loff_t *pos) | |
4985 | { | |
607e2ea1 | 4986 | struct trace_array *tr = m->private; |
f129e965 | 4987 | struct tracer *t; |
bc0c38d1 SR |
4988 | loff_t l = 0; |
4989 | ||
4990 | mutex_lock(&trace_types_lock); | |
607e2ea1 SRRH |
4991 | |
4992 | t = get_tracer_for_array(tr, trace_types); | |
4993 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
4994 | ; | |
bc0c38d1 SR |
4995 | |
4996 | return t; | |
4997 | } | |
4998 | ||
4999 | static void t_stop(struct seq_file *m, void *p) | |
5000 | { | |
5001 | mutex_unlock(&trace_types_lock); | |
5002 | } | |
5003 | ||
5004 | static int t_show(struct seq_file *m, void *v) | |
5005 | { | |
5006 | struct tracer *t = v; | |
5007 | ||
5008 | if (!t) | |
5009 | return 0; | |
5010 | ||
fa6f0cc7 | 5011 | seq_puts(m, t->name); |
bc0c38d1 SR |
5012 | if (t->next) |
5013 | seq_putc(m, ' '); | |
5014 | else | |
5015 | seq_putc(m, '\n'); | |
5016 | ||
5017 | return 0; | |
5018 | } | |
5019 | ||
88e9d34c | 5020 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
5021 | .start = t_start, |
5022 | .next = t_next, | |
5023 | .stop = t_stop, | |
5024 | .show = t_show, | |
bc0c38d1 SR |
5025 | }; |
5026 | ||
5027 | static int show_traces_open(struct inode *inode, struct file *file) | |
5028 | { | |
607e2ea1 SRRH |
5029 | struct trace_array *tr = inode->i_private; |
5030 | struct seq_file *m; | |
5031 | int ret; | |
5032 | ||
8530dec6 SRV |
5033 | ret = tracing_check_open_get_tr(tr); |
5034 | if (ret) | |
5035 | return ret; | |
194c2c74 | 5036 | |
607e2ea1 | 5037 | ret = seq_open(file, &show_traces_seq_ops); |
194c2c74 SRV |
5038 | if (ret) { |
5039 | trace_array_put(tr); | |
607e2ea1 | 5040 | return ret; |
194c2c74 | 5041 | } |
607e2ea1 SRRH |
5042 | |
5043 | m = file->private_data; | |
5044 | m->private = tr; | |
5045 | ||
5046 | return 0; | |
bc0c38d1 SR |
5047 | } |
5048 | ||
194c2c74 SRV |
5049 | static int show_traces_release(struct inode *inode, struct file *file) |
5050 | { | |
5051 | struct trace_array *tr = inode->i_private; | |
5052 | ||
5053 | trace_array_put(tr); | |
5054 | return seq_release(inode, file); | |
5055 | } | |
5056 | ||
4acd4d00 SR |
5057 | static ssize_t |
5058 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
5059 | size_t count, loff_t *ppos) | |
5060 | { | |
5061 | return count; | |
5062 | } | |
5063 | ||
098c879e | 5064 | loff_t tracing_lseek(struct file *file, loff_t offset, int whence) |
364829b1 | 5065 | { |
098c879e SRRH |
5066 | int ret; |
5067 | ||
364829b1 | 5068 | if (file->f_mode & FMODE_READ) |
098c879e | 5069 | ret = seq_lseek(file, offset, whence); |
364829b1 | 5070 | else |
098c879e SRRH |
5071 | file->f_pos = ret = 0; |
5072 | ||
5073 | return ret; | |
364829b1 SP |
5074 | } |
5075 | ||
5e2336a0 | 5076 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
5077 | .open = tracing_open, |
5078 | .read = seq_read, | |
4acd4d00 | 5079 | .write = tracing_write_stub, |
098c879e | 5080 | .llseek = tracing_lseek, |
4bf39a94 | 5081 | .release = tracing_release, |
bc0c38d1 SR |
5082 | }; |
5083 | ||
5e2336a0 | 5084 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
5085 | .open = show_traces_open, |
5086 | .read = seq_read, | |
b444786f | 5087 | .llseek = seq_lseek, |
194c2c74 | 5088 | .release = show_traces_release, |
c7078de1 IM |
5089 | }; |
5090 | ||
5091 | static ssize_t | |
5092 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
5093 | size_t count, loff_t *ppos) | |
5094 | { | |
ccfe9e42 | 5095 | struct trace_array *tr = file_inode(filp)->i_private; |
90e406f9 | 5096 | char *mask_str; |
36dfe925 | 5097 | int len; |
c7078de1 | 5098 | |
90e406f9 CD |
5099 | len = snprintf(NULL, 0, "%*pb\n", |
5100 | cpumask_pr_args(tr->tracing_cpumask)) + 1; | |
5101 | mask_str = kmalloc(len, GFP_KERNEL); | |
5102 | if (!mask_str) | |
5103 | return -ENOMEM; | |
36dfe925 | 5104 | |
90e406f9 | 5105 | len = snprintf(mask_str, len, "%*pb\n", |
1a40243b TH |
5106 | cpumask_pr_args(tr->tracing_cpumask)); |
5107 | if (len >= count) { | |
36dfe925 IM |
5108 | count = -EINVAL; |
5109 | goto out_err; | |
5110 | } | |
90e406f9 | 5111 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, len); |
36dfe925 IM |
5112 | |
5113 | out_err: | |
90e406f9 | 5114 | kfree(mask_str); |
c7078de1 IM |
5115 | |
5116 | return count; | |
5117 | } | |
5118 | ||
9d15dbbd MH |
5119 | int tracing_set_cpumask(struct trace_array *tr, |
5120 | cpumask_var_t tracing_cpumask_new) | |
c7078de1 | 5121 | { |
9d15dbbd | 5122 | int cpu; |
c7078de1 | 5123 | |
9d15dbbd MH |
5124 | if (!tr) |
5125 | return -EINVAL; | |
36dfe925 | 5126 | |
a5e25883 | 5127 | local_irq_disable(); |
0b9b12c1 | 5128 | arch_spin_lock(&tr->max_lock); |
ab46428c | 5129 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
5130 | /* |
5131 | * Increase/decrease the disabled counter if we are | |
5132 | * about to flip a bit in the cpumask: | |
5133 | */ | |
ccfe9e42 | 5134 | if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 5135 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
1c5eb448 SRV |
5136 | atomic_inc(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled); |
5137 | ring_buffer_record_disable_cpu(tr->array_buffer.buffer, cpu); | |
36dfe925 | 5138 | } |
ccfe9e42 | 5139 | if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 5140 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
1c5eb448 SRV |
5141 | atomic_dec(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled); |
5142 | ring_buffer_record_enable_cpu(tr->array_buffer.buffer, cpu); | |
36dfe925 IM |
5143 | } |
5144 | } | |
0b9b12c1 | 5145 | arch_spin_unlock(&tr->max_lock); |
a5e25883 | 5146 | local_irq_enable(); |
36dfe925 | 5147 | |
ccfe9e42 | 5148 | cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); |
9d15dbbd MH |
5149 | |
5150 | return 0; | |
5151 | } | |
5152 | ||
5153 | static ssize_t | |
5154 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
5155 | size_t count, loff_t *ppos) | |
5156 | { | |
5157 | struct trace_array *tr = file_inode(filp)->i_private; | |
5158 | cpumask_var_t tracing_cpumask_new; | |
5159 | int err; | |
5160 | ||
c5e3a411 | 5161 | if (!zalloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) |
9d15dbbd MH |
5162 | return -ENOMEM; |
5163 | ||
5164 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); | |
5165 | if (err) | |
5166 | goto err_free; | |
5167 | ||
5168 | err = tracing_set_cpumask(tr, tracing_cpumask_new); | |
5169 | if (err) | |
5170 | goto err_free; | |
5171 | ||
9e01c1b7 | 5172 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
5173 | |
5174 | return count; | |
36dfe925 | 5175 | |
9d15dbbd | 5176 | err_free: |
215368e8 | 5177 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
5178 | |
5179 | return err; | |
c7078de1 IM |
5180 | } |
5181 | ||
5e2336a0 | 5182 | static const struct file_operations tracing_cpumask_fops = { |
ccfe9e42 | 5183 | .open = tracing_open_generic_tr, |
c7078de1 IM |
5184 | .read = tracing_cpumask_read, |
5185 | .write = tracing_cpumask_write, | |
ccfe9e42 | 5186 | .release = tracing_release_generic_tr, |
b444786f | 5187 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5188 | }; |
5189 | ||
fdb372ed | 5190 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 5191 | { |
d8e83d26 | 5192 | struct tracer_opt *trace_opts; |
2b6080f2 | 5193 | struct trace_array *tr = m->private; |
d8e83d26 | 5194 | u32 tracer_flags; |
d8e83d26 | 5195 | int i; |
adf9f195 | 5196 | |
d8e83d26 | 5197 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
5198 | tracer_flags = tr->current_trace->flags->val; |
5199 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 5200 | |
bc0c38d1 | 5201 | for (i = 0; trace_options[i]; i++) { |
983f938a | 5202 | if (tr->trace_flags & (1 << i)) |
fdb372ed | 5203 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 5204 | else |
fdb372ed | 5205 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
5206 | } |
5207 | ||
adf9f195 FW |
5208 | for (i = 0; trace_opts[i].name; i++) { |
5209 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 5210 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 5211 | else |
fdb372ed | 5212 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 5213 | } |
d8e83d26 | 5214 | mutex_unlock(&trace_types_lock); |
adf9f195 | 5215 | |
fdb372ed | 5216 | return 0; |
bc0c38d1 | 5217 | } |
bc0c38d1 | 5218 | |
8c1a49ae | 5219 | static int __set_tracer_option(struct trace_array *tr, |
8d18eaaf LZ |
5220 | struct tracer_flags *tracer_flags, |
5221 | struct tracer_opt *opts, int neg) | |
5222 | { | |
d39cdd20 | 5223 | struct tracer *trace = tracer_flags->trace; |
8d18eaaf | 5224 | int ret; |
bc0c38d1 | 5225 | |
8c1a49ae | 5226 | ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); |
8d18eaaf LZ |
5227 | if (ret) |
5228 | return ret; | |
5229 | ||
5230 | if (neg) | |
5231 | tracer_flags->val &= ~opts->bit; | |
5232 | else | |
5233 | tracer_flags->val |= opts->bit; | |
5234 | return 0; | |
bc0c38d1 SR |
5235 | } |
5236 | ||
adf9f195 | 5237 | /* Try to assign a tracer specific option */ |
8c1a49ae | 5238 | static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) |
adf9f195 | 5239 | { |
8c1a49ae | 5240 | struct tracer *trace = tr->current_trace; |
7770841e | 5241 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 5242 | struct tracer_opt *opts = NULL; |
8d18eaaf | 5243 | int i; |
adf9f195 | 5244 | |
7770841e Z |
5245 | for (i = 0; tracer_flags->opts[i].name; i++) { |
5246 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 5247 | |
8d18eaaf | 5248 | if (strcmp(cmp, opts->name) == 0) |
8c1a49ae | 5249 | return __set_tracer_option(tr, trace->flags, opts, neg); |
adf9f195 | 5250 | } |
adf9f195 | 5251 | |
8d18eaaf | 5252 | return -EINVAL; |
adf9f195 FW |
5253 | } |
5254 | ||
613f04a0 SRRH |
5255 | /* Some tracers require overwrite to stay enabled */ |
5256 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
5257 | { | |
5258 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
5259 | return -1; | |
5260 | ||
5261 | return 0; | |
5262 | } | |
5263 | ||
2b6080f2 | 5264 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd | 5265 | { |
4030a6e6 PB |
5266 | int *map; |
5267 | ||
3a53acf1 PS |
5268 | if ((mask == TRACE_ITER_RECORD_TGID) || |
5269 | (mask == TRACE_ITER_RECORD_CMD)) | |
5270 | lockdep_assert_held(&event_mutex); | |
5271 | ||
af4617bd | 5272 | /* do nothing if flag is already set */ |
983f938a | 5273 | if (!!(tr->trace_flags & mask) == !!enabled) |
613f04a0 SRRH |
5274 | return 0; |
5275 | ||
5276 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 | 5277 | if (tr->current_trace->flag_changed) |
bf6065b5 | 5278 | if (tr->current_trace->flag_changed(tr, mask, !!enabled)) |
613f04a0 | 5279 | return -EINVAL; |
af4617bd SR |
5280 | |
5281 | if (enabled) | |
983f938a | 5282 | tr->trace_flags |= mask; |
af4617bd | 5283 | else |
983f938a | 5284 | tr->trace_flags &= ~mask; |
e870e9a1 LZ |
5285 | |
5286 | if (mask == TRACE_ITER_RECORD_CMD) | |
5287 | trace_event_enable_cmd_record(enabled); | |
750912fa | 5288 | |
d914ba37 | 5289 | if (mask == TRACE_ITER_RECORD_TGID) { |
4030a6e6 PB |
5290 | if (!tgid_map) { |
5291 | tgid_map_max = pid_max; | |
5292 | map = kvcalloc(tgid_map_max + 1, sizeof(*tgid_map), | |
5293 | GFP_KERNEL); | |
5294 | ||
5295 | /* | |
5296 | * Pairs with smp_load_acquire() in | |
5297 | * trace_find_tgid_ptr() to ensure that if it observes | |
5298 | * the tgid_map we just allocated then it also observes | |
5299 | * the corresponding tgid_map_max value. | |
5300 | */ | |
5301 | smp_store_release(&tgid_map, map); | |
5302 | } | |
d914ba37 JF |
5303 | if (!tgid_map) { |
5304 | tr->trace_flags &= ~TRACE_ITER_RECORD_TGID; | |
5305 | return -ENOMEM; | |
5306 | } | |
5307 | ||
5308 | trace_event_enable_tgid_record(enabled); | |
5309 | } | |
5310 | ||
c37775d5 SR |
5311 | if (mask == TRACE_ITER_EVENT_FORK) |
5312 | trace_event_follow_fork(tr, enabled); | |
5313 | ||
1e10486f NK |
5314 | if (mask == TRACE_ITER_FUNC_FORK) |
5315 | ftrace_pid_follow_fork(tr, enabled); | |
5316 | ||
80902822 | 5317 | if (mask == TRACE_ITER_OVERWRITE) { |
1c5eb448 | 5318 | ring_buffer_change_overwrite(tr->array_buffer.buffer, enabled); |
80902822 | 5319 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 5320 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
5321 | #endif |
5322 | } | |
81698831 | 5323 | |
b9f9108c | 5324 | if (mask == TRACE_ITER_PRINTK) { |
81698831 | 5325 | trace_printk_start_stop_comm(enabled); |
b9f9108c SRRH |
5326 | trace_printk_control(enabled); |
5327 | } | |
613f04a0 SRRH |
5328 | |
5329 | return 0; | |
af4617bd SR |
5330 | } |
5331 | ||
9c5b9d3d | 5332 | int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 5333 | { |
8d18eaaf | 5334 | char *cmp; |
bc0c38d1 | 5335 | int neg = 0; |
591a033d | 5336 | int ret; |
a4d1e688 | 5337 | size_t orig_len = strlen(option); |
3d739c1f | 5338 | int len; |
bc0c38d1 | 5339 | |
7bcfaf54 | 5340 | cmp = strstrip(option); |
bc0c38d1 | 5341 | |
3d739c1f SRV |
5342 | len = str_has_prefix(cmp, "no"); |
5343 | if (len) | |
bc0c38d1 | 5344 | neg = 1; |
3d739c1f SRV |
5345 | |
5346 | cmp += len; | |
bc0c38d1 | 5347 | |
3a53acf1 | 5348 | mutex_lock(&event_mutex); |
69d34da2 SRRH |
5349 | mutex_lock(&trace_types_lock); |
5350 | ||
591a033d | 5351 | ret = match_string(trace_options, -1, cmp); |
adf9f195 | 5352 | /* If no option could be set, test the specific tracer options */ |
591a033d | 5353 | if (ret < 0) |
8c1a49ae | 5354 | ret = set_tracer_option(tr, cmp, neg); |
591a033d YX |
5355 | else |
5356 | ret = set_tracer_flag(tr, 1 << ret, !neg); | |
69d34da2 SRRH |
5357 | |
5358 | mutex_unlock(&trace_types_lock); | |
3a53acf1 | 5359 | mutex_unlock(&event_mutex); |
bc0c38d1 | 5360 | |
a4d1e688 JW |
5361 | /* |
5362 | * If the first trailing whitespace is replaced with '\0' by strstrip, | |
5363 | * turn it back into a space. | |
5364 | */ | |
5365 | if (orig_len > strlen(option)) | |
5366 | option[strlen(option)] = ' '; | |
5367 | ||
7bcfaf54 SR |
5368 | return ret; |
5369 | } | |
5370 | ||
a4d1e688 JW |
5371 | static void __init apply_trace_boot_options(void) |
5372 | { | |
5373 | char *buf = trace_boot_options_buf; | |
5374 | char *option; | |
5375 | ||
5376 | while (true) { | |
5377 | option = strsep(&buf, ","); | |
5378 | ||
5379 | if (!option) | |
5380 | break; | |
a4d1e688 | 5381 | |
43ed3843 SRRH |
5382 | if (*option) |
5383 | trace_set_options(&global_trace, option); | |
a4d1e688 JW |
5384 | |
5385 | /* Put back the comma to allow this to be called again */ | |
5386 | if (buf) | |
5387 | *(buf - 1) = ','; | |
5388 | } | |
5389 | } | |
5390 | ||
7bcfaf54 SR |
5391 | static ssize_t |
5392 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
5393 | size_t cnt, loff_t *ppos) | |
5394 | { | |
2b6080f2 SR |
5395 | struct seq_file *m = filp->private_data; |
5396 | struct trace_array *tr = m->private; | |
7bcfaf54 | 5397 | char buf[64]; |
613f04a0 | 5398 | int ret; |
7bcfaf54 SR |
5399 | |
5400 | if (cnt >= sizeof(buf)) | |
5401 | return -EINVAL; | |
5402 | ||
4afe6495 | 5403 | if (copy_from_user(buf, ubuf, cnt)) |
7bcfaf54 SR |
5404 | return -EFAULT; |
5405 | ||
a8dd2176 SR |
5406 | buf[cnt] = 0; |
5407 | ||
2b6080f2 | 5408 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
5409 | if (ret < 0) |
5410 | return ret; | |
7bcfaf54 | 5411 | |
cf8517cf | 5412 | *ppos += cnt; |
bc0c38d1 SR |
5413 | |
5414 | return cnt; | |
5415 | } | |
5416 | ||
fdb372ed LZ |
5417 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
5418 | { | |
7b85af63 | 5419 | struct trace_array *tr = inode->i_private; |
f77d09a3 | 5420 | int ret; |
7b85af63 | 5421 | |
8530dec6 SRV |
5422 | ret = tracing_check_open_get_tr(tr); |
5423 | if (ret) | |
5424 | return ret; | |
7b85af63 | 5425 | |
f77d09a3 AL |
5426 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
5427 | if (ret < 0) | |
5428 | trace_array_put(tr); | |
5429 | ||
5430 | return ret; | |
fdb372ed LZ |
5431 | } |
5432 | ||
5e2336a0 | 5433 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
5434 | .open = tracing_trace_options_open, |
5435 | .read = seq_read, | |
5436 | .llseek = seq_lseek, | |
7b85af63 | 5437 | .release = tracing_single_release_tr, |
ee6bce52 | 5438 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
5439 | }; |
5440 | ||
7bd2f24c IM |
5441 | static const char readme_msg[] = |
5442 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
5443 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
5444 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
5445 | " Important files:\n" | |
5446 | " trace\t\t\t- The static contents of the buffer\n" | |
5447 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
5448 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
5449 | " current_tracer\t- function and latency tracers\n" | |
5450 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
a8d65579 | 5451 | " error_log\t- error log for failed commands (that support it)\n" |
22f45649 SRRH |
5452 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" |
5453 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
5454 | " trace_clock\t\t-change the clock used to order events\n" | |
5455 | " local: Per cpu clock but may not be synced across CPUs\n" | |
5456 | " global: Synced across CPUs but slows tracing down.\n" | |
5457 | " counter: Not a clock, but just an increment\n" | |
5458 | " uptime: Jiffy counter from time of boot\n" | |
5459 | " perf: Same clock that perf events use\n" | |
5460 | #ifdef CONFIG_X86_64 | |
5461 | " x86-tsc: TSC cycle counter\n" | |
5462 | #endif | |
2c1ea60b TZ |
5463 | "\n timestamp_mode\t-view the mode used to timestamp events\n" |
5464 | " delta: Delta difference against a buffer-wide timestamp\n" | |
5465 | " absolute: Absolute (standalone) timestamp\n" | |
22f45649 | 5466 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" |
fa32e855 | 5467 | "\n trace_marker_raw\t\t- Writes into this file writes binary data into the kernel buffer\n" |
22f45649 SRRH |
5468 | " tracing_cpumask\t- Limit which CPUs to trace\n" |
5469 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
5470 | "\t\t\t Remove sub-buffer with rmdir\n" | |
5471 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
b9416997 | 5472 | "\t\t\t Disable an option by prefixing 'no' to the\n" |
71485c45 | 5473 | "\t\t\t option name\n" |
939c7a4f | 5474 | " saved_cmdlines_size\t- echo command number in here to store comm-pid list\n" |
22f45649 SRRH |
5475 | #ifdef CONFIG_DYNAMIC_FTRACE |
5476 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
71485c45 SRRH |
5477 | " set_ftrace_filter\t- echo function name in here to only trace these\n" |
5478 | "\t\t\t functions\n" | |
60f1d5e3 | 5479 | "\t accepts: func_full_name or glob-matching-pattern\n" |
71485c45 SRRH |
5480 | "\t modules: Can select a group via module\n" |
5481 | "\t Format: :mod:<module-name>\n" | |
5482 | "\t example: echo :mod:ext3 > set_ftrace_filter\n" | |
5483 | "\t triggers: a command to perform when function is hit\n" | |
5484 | "\t Format: <function>:<trigger>[:count]\n" | |
5485 | "\t trigger: traceon, traceoff\n" | |
5486 | "\t\t enable_event:<system>:<event>\n" | |
5487 | "\t\t disable_event:<system>:<event>\n" | |
22f45649 | 5488 | #ifdef CONFIG_STACKTRACE |
71485c45 | 5489 | "\t\t stacktrace\n" |
22f45649 SRRH |
5490 | #endif |
5491 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 5492 | "\t\t snapshot\n" |
22f45649 | 5493 | #endif |
17a280ea SRRH |
5494 | "\t\t dump\n" |
5495 | "\t\t cpudump\n" | |
71485c45 SRRH |
5496 | "\t example: echo do_fault:traceoff > set_ftrace_filter\n" |
5497 | "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
5498 | "\t The first one will disable tracing every time do_fault is hit\n" | |
5499 | "\t The second will disable tracing at most 3 times when do_trap is hit\n" | |
5500 | "\t The first time do trap is hit and it disables tracing, the\n" | |
5501 | "\t counter will decrement to 2. If tracing is already disabled,\n" | |
5502 | "\t the counter will not decrement. It only decrements when the\n" | |
5503 | "\t trigger did work\n" | |
5504 | "\t To remove trigger without count:\n" | |
5505 | "\t echo '!<function>:<trigger> > set_ftrace_filter\n" | |
5506 | "\t To remove trigger with a count:\n" | |
5507 | "\t echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
22f45649 | 5508 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" |
71485c45 SRRH |
5509 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" |
5510 | "\t modules: Can select a group via module command :mod:\n" | |
5511 | "\t Does not accept triggers\n" | |
22f45649 SRRH |
5512 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
5513 | #ifdef CONFIG_FUNCTION_TRACER | |
71485c45 SRRH |
5514 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" |
5515 | "\t\t (function)\n" | |
b3b1e6ed SRV |
5516 | " set_ftrace_notrace_pid\t- Write pid(s) to not function trace those pids\n" |
5517 | "\t\t (function)\n" | |
22f45649 SRRH |
5518 | #endif |
5519 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
5520 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
d048a8c7 | 5521 | " set_graph_notrace\t- Do not trace the nested calls of a function (function_graph)\n" |
22f45649 SRRH |
5522 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" |
5523 | #endif | |
5524 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 SRRH |
5525 | "\n snapshot\t\t- Like 'trace' but shows the content of the static\n" |
5526 | "\t\t\t snapshot buffer. Read the contents for more\n" | |
5527 | "\t\t\t information\n" | |
22f45649 | 5528 | #endif |
991821c8 | 5529 | #ifdef CONFIG_STACK_TRACER |
22f45649 SRRH |
5530 | " stack_trace\t\t- Shows the max stack trace when active\n" |
5531 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
71485c45 SRRH |
5532 | "\t\t\t Write into this file to reset the max size (trigger a\n" |
5533 | "\t\t\t new trace)\n" | |
22f45649 | 5534 | #ifdef CONFIG_DYNAMIC_FTRACE |
71485c45 SRRH |
5535 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n" |
5536 | "\t\t\t traces\n" | |
22f45649 | 5537 | #endif |
991821c8 | 5538 | #endif /* CONFIG_STACK_TRACER */ |
5448d44c | 5539 | #ifdef CONFIG_DYNAMIC_EVENTS |
ca89bc07 | 5540 | " dynamic_events\t\t- Create/append/remove/show the generic dynamic events\n" |
5448d44c MH |
5541 | "\t\t\t Write into this file to define/undefine new trace events.\n" |
5542 | #endif | |
6b0b7551 | 5543 | #ifdef CONFIG_KPROBE_EVENTS |
ca89bc07 | 5544 | " kprobe_events\t\t- Create/append/remove/show the kernel dynamic events\n" |
86425625 MH |
5545 | "\t\t\t Write into this file to define/undefine new trace events.\n" |
5546 | #endif | |
6b0b7551 | 5547 | #ifdef CONFIG_UPROBE_EVENTS |
41af3cf5 | 5548 | " uprobe_events\t\t- Create/append/remove/show the userspace dynamic events\n" |
86425625 MH |
5549 | "\t\t\t Write into this file to define/undefine new trace events.\n" |
5550 | #endif | |
6b0b7551 | 5551 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
86425625 | 5552 | "\t accepts: event-definitions (one definition per line)\n" |
c3ca46ef MH |
5553 | "\t Format: p[:[<group>/]<event>] <place> [<args>]\n" |
5554 | "\t r[maxactive][:[<group>/]<event>] <place> [<args>]\n" | |
7bbab38d MH |
5555 | #ifdef CONFIG_HIST_TRIGGERS |
5556 | "\t s:[synthetic/]<event> <field> [<field>]\n" | |
5557 | #endif | |
7491e2c4 | 5558 | "\t e[:[<group>/]<event>] <attached-group>.<attached-event> [<args>]\n" |
86425625 | 5559 | "\t -:[<group>/]<event>\n" |
6b0b7551 | 5560 | #ifdef CONFIG_KPROBE_EVENTS |
86425625 | 5561 | "\t place: [<module>:]<symbol>[+<offset>]|<memaddr>\n" |
4725cd89 | 5562 | "place (kretprobe): [<module>:]<symbol>[+<offset>]%return|<memaddr>\n" |
86425625 | 5563 | #endif |
6b0b7551 | 5564 | #ifdef CONFIG_UPROBE_EVENTS |
3dd3aae3 | 5565 | " place (uprobe): <path>:<offset>[%return][(ref_ctr_offset)]\n" |
86425625 MH |
5566 | #endif |
5567 | "\t args: <name>=fetcharg[:type]\n" | |
7491e2c4 | 5568 | "\t fetcharg: (%<register>|$<efield>), @<address>, @<symbol>[+|-<offset>],\n" |
a1303af5 | 5569 | #ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API |
e65f7ae7 | 5570 | "\t $stack<index>, $stack, $retval, $comm, $arg<N>,\n" |
a1303af5 | 5571 | #else |
e65f7ae7 | 5572 | "\t $stack<index>, $stack, $retval, $comm,\n" |
a1303af5 | 5573 | #endif |
a42e3c4d | 5574 | "\t +|-[u]<offset>(<fetcharg>), \\imm-value, \\\"imm-string\"\n" |
60c2e0ce | 5575 | "\t type: s8/16/32/64, u8/16/32/64, x8/16/32/64, string, symbol,\n" |
88903c46 | 5576 | "\t b<bit-width>@<bit-offset>/<container-size>, ustring,\n" |
40b53b77 | 5577 | "\t <type>\\[<array-size>\\]\n" |
7bbab38d MH |
5578 | #ifdef CONFIG_HIST_TRIGGERS |
5579 | "\t field: <stype> <name>;\n" | |
5580 | "\t stype: u8/u16/u32/u64, s8/s16/s32/s64, pid_t,\n" | |
5581 | "\t [unsigned] char/int/long\n" | |
5582 | #endif | |
7491e2c4 TSV |
5583 | "\t efield: For event probes ('e' types), the field is on of the fields\n" |
5584 | "\t of the <attached-group>/<attached-event>.\n" | |
86425625 | 5585 | #endif |
26f25564 TZ |
5586 | " events/\t\t- Directory containing all trace event subsystems:\n" |
5587 | " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" | |
5588 | " events/<system>/\t- Directory containing all trace events for <system>:\n" | |
71485c45 SRRH |
5589 | " enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n" |
5590 | "\t\t\t events\n" | |
26f25564 | 5591 | " filter\t\t- If set, only events passing filter are traced\n" |
71485c45 SRRH |
5592 | " events/<system>/<event>/\t- Directory containing control files for\n" |
5593 | "\t\t\t <event>:\n" | |
26f25564 TZ |
5594 | " enable\t\t- Write 0/1 to enable/disable tracing of <event>\n" |
5595 | " filter\t\t- If set, only events passing filter are traced\n" | |
5596 | " trigger\t\t- If set, a command to perform when event is hit\n" | |
71485c45 SRRH |
5597 | "\t Format: <trigger>[:count][if <filter>]\n" |
5598 | "\t trigger: traceon, traceoff\n" | |
5599 | "\t enable_event:<system>:<event>\n" | |
5600 | "\t disable_event:<system>:<event>\n" | |
d0bad49b TZ |
5601 | #ifdef CONFIG_HIST_TRIGGERS |
5602 | "\t enable_hist:<system>:<event>\n" | |
5603 | "\t disable_hist:<system>:<event>\n" | |
5604 | #endif | |
26f25564 | 5605 | #ifdef CONFIG_STACKTRACE |
71485c45 | 5606 | "\t\t stacktrace\n" |
26f25564 TZ |
5607 | #endif |
5608 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 5609 | "\t\t snapshot\n" |
7ef224d1 TZ |
5610 | #endif |
5611 | #ifdef CONFIG_HIST_TRIGGERS | |
5612 | "\t\t hist (see below)\n" | |
26f25564 | 5613 | #endif |
71485c45 SRRH |
5614 | "\t example: echo traceoff > events/block/block_unplug/trigger\n" |
5615 | "\t echo traceoff:3 > events/block/block_unplug/trigger\n" | |
5616 | "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" | |
5617 | "\t events/block/block_unplug/trigger\n" | |
5618 | "\t The first disables tracing every time block_unplug is hit.\n" | |
5619 | "\t The second disables tracing the first 3 times block_unplug is hit.\n" | |
5620 | "\t The third enables the kmalloc event the first 3 times block_unplug\n" | |
5621 | "\t is hit and has value of greater than 1 for the 'nr_rq' event field.\n" | |
5622 | "\t Like function triggers, the counter is only decremented if it\n" | |
5623 | "\t enabled or disabled tracing.\n" | |
5624 | "\t To remove a trigger without a count:\n" | |
5625 | "\t echo '!<trigger> > <system>/<event>/trigger\n" | |
5626 | "\t To remove a trigger with a count:\n" | |
5627 | "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" | |
5628 | "\t Filters can be ignored when removing a trigger.\n" | |
7ef224d1 TZ |
5629 | #ifdef CONFIG_HIST_TRIGGERS |
5630 | " hist trigger\t- If set, event hits are aggregated into a hash table\n" | |
76a3b0c8 | 5631 | "\t Format: hist:keys=<field1[,field2,...]>\n" |
f2606835 | 5632 | "\t [:values=<field1[,field2,...]>]\n" |
e62347d2 | 5633 | "\t [:sort=<field1[,field2,...]>]\n" |
7ef224d1 | 5634 | "\t [:size=#entries]\n" |
e86ae9ba | 5635 | "\t [:pause][:continue][:clear]\n" |
5463bfda | 5636 | "\t [:name=histname1]\n" |
c3e49506 | 5637 | "\t [:<handler>.<action>]\n" |
7ef224d1 | 5638 | "\t [if <filter>]\n\n" |
1e3bac71 SRV |
5639 | "\t Note, special fields can be used as well:\n" |
5640 | "\t common_timestamp - to record current timestamp\n" | |
5641 | "\t common_cpu - to record the CPU the event happened on\n" | |
5642 | "\n" | |
7ef224d1 | 5643 | "\t When a matching event is hit, an entry is added to a hash\n" |
f2606835 TZ |
5644 | "\t table using the key(s) and value(s) named, and the value of a\n" |
5645 | "\t sum called 'hitcount' is incremented. Keys and values\n" | |
5646 | "\t correspond to fields in the event's format description. Keys\n" | |
69a0200c TZ |
5647 | "\t can be any field, or the special string 'stacktrace'.\n" |
5648 | "\t Compound keys consisting of up to two fields can be specified\n" | |
5649 | "\t by the 'keys' keyword. Values must correspond to numeric\n" | |
5650 | "\t fields. Sort keys consisting of up to two fields can be\n" | |
5651 | "\t specified using the 'sort' keyword. The sort direction can\n" | |
5652 | "\t be modified by appending '.descending' or '.ascending' to a\n" | |
5653 | "\t sort field. The 'size' parameter can be used to specify more\n" | |
5463bfda TZ |
5654 | "\t or fewer than the default 2048 entries for the hashtable size.\n" |
5655 | "\t If a hist trigger is given a name using the 'name' parameter,\n" | |
5656 | "\t its histogram data will be shared with other triggers of the\n" | |
5657 | "\t same name, and trigger hits will update this common data.\n\n" | |
7ef224d1 | 5658 | "\t Reading the 'hist' file for the event will dump the hash\n" |
52a7f16d TZ |
5659 | "\t table in its entirety to stdout. If there are multiple hist\n" |
5660 | "\t triggers attached to an event, there will be a table for each\n" | |
5463bfda TZ |
5661 | "\t trigger in the output. The table displayed for a named\n" |
5662 | "\t trigger will be the same as any other instance having the\n" | |
5663 | "\t same name. The default format used to display a given field\n" | |
5664 | "\t can be modified by appending any of the following modifiers\n" | |
5665 | "\t to the field name, as applicable:\n\n" | |
c6afad49 TZ |
5666 | "\t .hex display a number as a hex value\n" |
5667 | "\t .sym display an address as a symbol\n" | |
6b4827ad | 5668 | "\t .sym-offset display an address as a symbol and offset\n" |
31696198 | 5669 | "\t .execname display a common_pid as a program name\n" |
860f9f6b TZ |
5670 | "\t .syscall display a syscall id as a syscall name\n" |
5671 | "\t .log2 display log2 value rather than raw number\n" | |
37036435 | 5672 | "\t .buckets=size display values in groups of size rather than raw number\n" |
860f9f6b | 5673 | "\t .usecs display a common_timestamp in microseconds\n\n" |
83e99914 TZ |
5674 | "\t The 'pause' parameter can be used to pause an existing hist\n" |
5675 | "\t trigger or to start a hist trigger but not log any events\n" | |
5676 | "\t until told to do so. 'continue' can be used to start or\n" | |
5677 | "\t restart a paused hist trigger.\n\n" | |
e86ae9ba TZ |
5678 | "\t The 'clear' parameter will clear the contents of a running\n" |
5679 | "\t hist trigger and leave its current paused/active state\n" | |
5680 | "\t unchanged.\n\n" | |
d0bad49b TZ |
5681 | "\t The enable_hist and disable_hist triggers can be used to\n" |
5682 | "\t have one event conditionally start and stop another event's\n" | |
9e5a36a3 | 5683 | "\t already-attached hist trigger. The syntax is analogous to\n" |
c3e49506 TZ |
5684 | "\t the enable_event and disable_event triggers.\n\n" |
5685 | "\t Hist trigger handlers and actions are executed whenever a\n" | |
5686 | "\t a histogram entry is added or updated. They take the form:\n\n" | |
5687 | "\t <handler>.<action>\n\n" | |
5688 | "\t The available handlers are:\n\n" | |
5689 | "\t onmatch(matching.event) - invoke on addition or update\n" | |
dff81f55 TZ |
5690 | "\t onmax(var) - invoke if var exceeds current max\n" |
5691 | "\t onchange(var) - invoke action if var changes\n\n" | |
c3e49506 | 5692 | "\t The available actions are:\n\n" |
e91eefd7 | 5693 | "\t trace(<synthetic_event>,param list) - generate synthetic event\n" |
c3e49506 | 5694 | "\t save(field,...) - save current event fields\n" |
a3785b7e | 5695 | #ifdef CONFIG_TRACER_SNAPSHOT |
1bc36bd4 TZ |
5696 | "\t snapshot() - snapshot the trace buffer\n\n" |
5697 | #endif | |
5698 | #ifdef CONFIG_SYNTH_EVENTS | |
5699 | " events/synthetic_events\t- Create/append/remove/show synthetic events\n" | |
5700 | "\t Write into this file to define/undefine new synthetic events.\n" | |
5701 | "\t example: echo 'myevent u64 lat; char name[]' >> synthetic_events\n" | |
a3785b7e | 5702 | #endif |
7ef224d1 | 5703 | #endif |
7bd2f24c IM |
5704 | ; |
5705 | ||
5706 | static ssize_t | |
5707 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
5708 | size_t cnt, loff_t *ppos) | |
5709 | { | |
5710 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
5711 | readme_msg, strlen(readme_msg)); | |
5712 | } | |
5713 | ||
5e2336a0 | 5714 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
5715 | .open = tracing_open_generic, |
5716 | .read = tracing_readme_read, | |
b444786f | 5717 | .llseek = generic_file_llseek, |
7bd2f24c IM |
5718 | }; |
5719 | ||
99c621d7 MS |
5720 | static void *saved_tgids_next(struct seq_file *m, void *v, loff_t *pos) |
5721 | { | |
b81b3e95 | 5722 | int pid = ++(*pos); |
99c621d7 | 5723 | |
4030a6e6 | 5724 | return trace_find_tgid_ptr(pid); |
99c621d7 MS |
5725 | } |
5726 | ||
5727 | static void *saved_tgids_start(struct seq_file *m, loff_t *pos) | |
5728 | { | |
4030a6e6 | 5729 | int pid = *pos; |
99c621d7 | 5730 | |
4030a6e6 | 5731 | return trace_find_tgid_ptr(pid); |
99c621d7 MS |
5732 | } |
5733 | ||
5734 | static void saved_tgids_stop(struct seq_file *m, void *v) | |
5735 | { | |
5736 | } | |
5737 | ||
5738 | static int saved_tgids_show(struct seq_file *m, void *v) | |
5739 | { | |
b81b3e95 PB |
5740 | int *entry = (int *)v; |
5741 | int pid = entry - tgid_map; | |
5742 | int tgid = *entry; | |
99c621d7 | 5743 | |
b81b3e95 PB |
5744 | if (tgid == 0) |
5745 | return SEQ_SKIP; | |
99c621d7 | 5746 | |
b81b3e95 | 5747 | seq_printf(m, "%d %d\n", pid, tgid); |
99c621d7 MS |
5748 | return 0; |
5749 | } | |
5750 | ||
5751 | static const struct seq_operations tracing_saved_tgids_seq_ops = { | |
5752 | .start = saved_tgids_start, | |
5753 | .stop = saved_tgids_stop, | |
5754 | .next = saved_tgids_next, | |
5755 | .show = saved_tgids_show, | |
5756 | }; | |
5757 | ||
5758 | static int tracing_saved_tgids_open(struct inode *inode, struct file *filp) | |
5759 | { | |
8530dec6 SRV |
5760 | int ret; |
5761 | ||
5762 | ret = tracing_check_open_get_tr(NULL); | |
5763 | if (ret) | |
5764 | return ret; | |
99c621d7 MS |
5765 | |
5766 | return seq_open(filp, &tracing_saved_tgids_seq_ops); | |
5767 | } | |
5768 | ||
5769 | ||
5770 | static const struct file_operations tracing_saved_tgids_fops = { | |
5771 | .open = tracing_saved_tgids_open, | |
5772 | .read = seq_read, | |
5773 | .llseek = seq_lseek, | |
5774 | .release = seq_release, | |
5775 | }; | |
5776 | ||
42584c81 YY |
5777 | static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos) |
5778 | { | |
5779 | unsigned int *ptr = v; | |
69abe6a5 | 5780 | |
42584c81 YY |
5781 | if (*pos || m->count) |
5782 | ptr++; | |
69abe6a5 | 5783 | |
42584c81 | 5784 | (*pos)++; |
69abe6a5 | 5785 | |
939c7a4f YY |
5786 | for (; ptr < &savedcmd->map_cmdline_to_pid[savedcmd->cmdline_num]; |
5787 | ptr++) { | |
42584c81 YY |
5788 | if (*ptr == -1 || *ptr == NO_CMDLINE_MAP) |
5789 | continue; | |
69abe6a5 | 5790 | |
42584c81 YY |
5791 | return ptr; |
5792 | } | |
69abe6a5 | 5793 | |
42584c81 YY |
5794 | return NULL; |
5795 | } | |
5796 | ||
5797 | static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos) | |
5798 | { | |
5799 | void *v; | |
5800 | loff_t l = 0; | |
69abe6a5 | 5801 | |
4c27e756 SRRH |
5802 | preempt_disable(); |
5803 | arch_spin_lock(&trace_cmdline_lock); | |
5804 | ||
939c7a4f | 5805 | v = &savedcmd->map_cmdline_to_pid[0]; |
42584c81 YY |
5806 | while (l <= *pos) { |
5807 | v = saved_cmdlines_next(m, v, &l); | |
5808 | if (!v) | |
5809 | return NULL; | |
69abe6a5 AP |
5810 | } |
5811 | ||
42584c81 YY |
5812 | return v; |
5813 | } | |
5814 | ||
5815 | static void saved_cmdlines_stop(struct seq_file *m, void *v) | |
5816 | { | |
4c27e756 SRRH |
5817 | arch_spin_unlock(&trace_cmdline_lock); |
5818 | preempt_enable(); | |
42584c81 | 5819 | } |
69abe6a5 | 5820 | |
42584c81 YY |
5821 | static int saved_cmdlines_show(struct seq_file *m, void *v) |
5822 | { | |
5823 | char buf[TASK_COMM_LEN]; | |
5824 | unsigned int *pid = v; | |
69abe6a5 | 5825 | |
4c27e756 | 5826 | __trace_find_cmdline(*pid, buf); |
42584c81 YY |
5827 | seq_printf(m, "%d %s\n", *pid, buf); |
5828 | return 0; | |
5829 | } | |
5830 | ||
5831 | static const struct seq_operations tracing_saved_cmdlines_seq_ops = { | |
5832 | .start = saved_cmdlines_start, | |
5833 | .next = saved_cmdlines_next, | |
5834 | .stop = saved_cmdlines_stop, | |
5835 | .show = saved_cmdlines_show, | |
5836 | }; | |
5837 | ||
5838 | static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp) | |
5839 | { | |
8530dec6 SRV |
5840 | int ret; |
5841 | ||
5842 | ret = tracing_check_open_get_tr(NULL); | |
5843 | if (ret) | |
5844 | return ret; | |
42584c81 YY |
5845 | |
5846 | return seq_open(filp, &tracing_saved_cmdlines_seq_ops); | |
69abe6a5 AP |
5847 | } |
5848 | ||
5849 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
42584c81 YY |
5850 | .open = tracing_saved_cmdlines_open, |
5851 | .read = seq_read, | |
5852 | .llseek = seq_lseek, | |
5853 | .release = seq_release, | |
69abe6a5 AP |
5854 | }; |
5855 | ||
939c7a4f YY |
5856 | static ssize_t |
5857 | tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf, | |
5858 | size_t cnt, loff_t *ppos) | |
5859 | { | |
5860 | char buf[64]; | |
5861 | int r; | |
5862 | ||
5863 | arch_spin_lock(&trace_cmdline_lock); | |
a6af8fbf | 5864 | r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num); |
939c7a4f YY |
5865 | arch_spin_unlock(&trace_cmdline_lock); |
5866 | ||
5867 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5868 | } | |
5869 | ||
5870 | static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s) | |
5871 | { | |
5872 | kfree(s->saved_cmdlines); | |
5873 | kfree(s->map_cmdline_to_pid); | |
5874 | kfree(s); | |
5875 | } | |
5876 | ||
5877 | static int tracing_resize_saved_cmdlines(unsigned int val) | |
5878 | { | |
5879 | struct saved_cmdlines_buffer *s, *savedcmd_temp; | |
5880 | ||
a6af8fbf | 5881 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
939c7a4f YY |
5882 | if (!s) |
5883 | return -ENOMEM; | |
5884 | ||
5885 | if (allocate_cmdlines_buffer(val, s) < 0) { | |
5886 | kfree(s); | |
5887 | return -ENOMEM; | |
5888 | } | |
5889 | ||
5890 | arch_spin_lock(&trace_cmdline_lock); | |
5891 | savedcmd_temp = savedcmd; | |
5892 | savedcmd = s; | |
5893 | arch_spin_unlock(&trace_cmdline_lock); | |
5894 | free_saved_cmdlines_buffer(savedcmd_temp); | |
5895 | ||
5896 | return 0; | |
5897 | } | |
5898 | ||
5899 | static ssize_t | |
5900 | tracing_saved_cmdlines_size_write(struct file *filp, const char __user *ubuf, | |
5901 | size_t cnt, loff_t *ppos) | |
5902 | { | |
5903 | unsigned long val; | |
5904 | int ret; | |
5905 | ||
5906 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5907 | if (ret) | |
5908 | return ret; | |
5909 | ||
5910 | /* must have at least 1 entry or less than PID_MAX_DEFAULT */ | |
5911 | if (!val || val > PID_MAX_DEFAULT) | |
5912 | return -EINVAL; | |
5913 | ||
5914 | ret = tracing_resize_saved_cmdlines((unsigned int)val); | |
5915 | if (ret < 0) | |
5916 | return ret; | |
5917 | ||
5918 | *ppos += cnt; | |
5919 | ||
5920 | return cnt; | |
5921 | } | |
5922 | ||
5923 | static const struct file_operations tracing_saved_cmdlines_size_fops = { | |
5924 | .open = tracing_open_generic, | |
5925 | .read = tracing_saved_cmdlines_size_read, | |
5926 | .write = tracing_saved_cmdlines_size_write, | |
5927 | }; | |
5928 | ||
681bec03 | 5929 | #ifdef CONFIG_TRACE_EVAL_MAP_FILE |
23bf8cb8 | 5930 | static union trace_eval_map_item * |
f57a4143 | 5931 | update_eval_map(union trace_eval_map_item *ptr) |
9828413d | 5932 | { |
00f4b652 | 5933 | if (!ptr->map.eval_string) { |
9828413d SRRH |
5934 | if (ptr->tail.next) { |
5935 | ptr = ptr->tail.next; | |
5936 | /* Set ptr to the next real item (skip head) */ | |
5937 | ptr++; | |
5938 | } else | |
5939 | return NULL; | |
5940 | } | |
5941 | return ptr; | |
5942 | } | |
5943 | ||
f57a4143 | 5944 | static void *eval_map_next(struct seq_file *m, void *v, loff_t *pos) |
9828413d | 5945 | { |
23bf8cb8 | 5946 | union trace_eval_map_item *ptr = v; |
9828413d SRRH |
5947 | |
5948 | /* | |
5949 | * Paranoid! If ptr points to end, we don't want to increment past it. | |
5950 | * This really should never happen. | |
5951 | */ | |
039958a5 | 5952 | (*pos)++; |
f57a4143 | 5953 | ptr = update_eval_map(ptr); |
9828413d SRRH |
5954 | if (WARN_ON_ONCE(!ptr)) |
5955 | return NULL; | |
5956 | ||
5957 | ptr++; | |
f57a4143 | 5958 | ptr = update_eval_map(ptr); |
9828413d SRRH |
5959 | |
5960 | return ptr; | |
5961 | } | |
5962 | ||
f57a4143 | 5963 | static void *eval_map_start(struct seq_file *m, loff_t *pos) |
9828413d | 5964 | { |
23bf8cb8 | 5965 | union trace_eval_map_item *v; |
9828413d SRRH |
5966 | loff_t l = 0; |
5967 | ||
1793ed93 | 5968 | mutex_lock(&trace_eval_mutex); |
9828413d | 5969 | |
23bf8cb8 | 5970 | v = trace_eval_maps; |
9828413d SRRH |
5971 | if (v) |
5972 | v++; | |
5973 | ||
5974 | while (v && l < *pos) { | |
f57a4143 | 5975 | v = eval_map_next(m, v, &l); |
9828413d SRRH |
5976 | } |
5977 | ||
5978 | return v; | |
5979 | } | |
5980 | ||
f57a4143 | 5981 | static void eval_map_stop(struct seq_file *m, void *v) |
9828413d | 5982 | { |
1793ed93 | 5983 | mutex_unlock(&trace_eval_mutex); |
9828413d SRRH |
5984 | } |
5985 | ||
f57a4143 | 5986 | static int eval_map_show(struct seq_file *m, void *v) |
9828413d | 5987 | { |
23bf8cb8 | 5988 | union trace_eval_map_item *ptr = v; |
9828413d SRRH |
5989 | |
5990 | seq_printf(m, "%s %ld (%s)\n", | |
00f4b652 | 5991 | ptr->map.eval_string, ptr->map.eval_value, |
9828413d SRRH |
5992 | ptr->map.system); |
5993 | ||
5994 | return 0; | |
5995 | } | |
5996 | ||
f57a4143 JL |
5997 | static const struct seq_operations tracing_eval_map_seq_ops = { |
5998 | .start = eval_map_start, | |
5999 | .next = eval_map_next, | |
6000 | .stop = eval_map_stop, | |
6001 | .show = eval_map_show, | |
9828413d SRRH |
6002 | }; |
6003 | ||
f57a4143 | 6004 | static int tracing_eval_map_open(struct inode *inode, struct file *filp) |
9828413d | 6005 | { |
8530dec6 SRV |
6006 | int ret; |
6007 | ||
6008 | ret = tracing_check_open_get_tr(NULL); | |
6009 | if (ret) | |
6010 | return ret; | |
9828413d | 6011 | |
f57a4143 | 6012 | return seq_open(filp, &tracing_eval_map_seq_ops); |
9828413d SRRH |
6013 | } |
6014 | ||
f57a4143 JL |
6015 | static const struct file_operations tracing_eval_map_fops = { |
6016 | .open = tracing_eval_map_open, | |
9828413d SRRH |
6017 | .read = seq_read, |
6018 | .llseek = seq_lseek, | |
6019 | .release = seq_release, | |
6020 | }; | |
6021 | ||
23bf8cb8 | 6022 | static inline union trace_eval_map_item * |
5f60b351 | 6023 | trace_eval_jmp_to_tail(union trace_eval_map_item *ptr) |
9828413d SRRH |
6024 | { |
6025 | /* Return tail of array given the head */ | |
6026 | return ptr + ptr->head.length + 1; | |
6027 | } | |
6028 | ||
6029 | static void | |
f57a4143 | 6030 | trace_insert_eval_map_file(struct module *mod, struct trace_eval_map **start, |
9828413d SRRH |
6031 | int len) |
6032 | { | |
00f4b652 JL |
6033 | struct trace_eval_map **stop; |
6034 | struct trace_eval_map **map; | |
23bf8cb8 JL |
6035 | union trace_eval_map_item *map_array; |
6036 | union trace_eval_map_item *ptr; | |
9828413d SRRH |
6037 | |
6038 | stop = start + len; | |
6039 | ||
6040 | /* | |
23bf8cb8 | 6041 | * The trace_eval_maps contains the map plus a head and tail item, |
9828413d SRRH |
6042 | * where the head holds the module and length of array, and the |
6043 | * tail holds a pointer to the next list. | |
6044 | */ | |
6da2ec56 | 6045 | map_array = kmalloc_array(len + 2, sizeof(*map_array), GFP_KERNEL); |
9828413d | 6046 | if (!map_array) { |
f57a4143 | 6047 | pr_warn("Unable to allocate trace eval mapping\n"); |
9828413d SRRH |
6048 | return; |
6049 | } | |
6050 | ||
1793ed93 | 6051 | mutex_lock(&trace_eval_mutex); |
9828413d | 6052 | |
23bf8cb8 JL |
6053 | if (!trace_eval_maps) |
6054 | trace_eval_maps = map_array; | |
9828413d | 6055 | else { |
23bf8cb8 | 6056 | ptr = trace_eval_maps; |
9828413d | 6057 | for (;;) { |
5f60b351 | 6058 | ptr = trace_eval_jmp_to_tail(ptr); |
9828413d SRRH |
6059 | if (!ptr->tail.next) |
6060 | break; | |
6061 | ptr = ptr->tail.next; | |
6062 | ||
6063 | } | |
6064 | ptr->tail.next = map_array; | |
6065 | } | |
6066 | map_array->head.mod = mod; | |
6067 | map_array->head.length = len; | |
6068 | map_array++; | |
6069 | ||
6070 | for (map = start; (unsigned long)map < (unsigned long)stop; map++) { | |
6071 | map_array->map = **map; | |
6072 | map_array++; | |
6073 | } | |
6074 | memset(map_array, 0, sizeof(*map_array)); | |
6075 | ||
1793ed93 | 6076 | mutex_unlock(&trace_eval_mutex); |
9828413d SRRH |
6077 | } |
6078 | ||
f57a4143 | 6079 | static void trace_create_eval_file(struct dentry *d_tracer) |
9828413d | 6080 | { |
bd324cfc | 6081 | trace_create_file("eval_map", TRACE_MODE_READ, d_tracer, |
f57a4143 | 6082 | NULL, &tracing_eval_map_fops); |
9828413d SRRH |
6083 | } |
6084 | ||
681bec03 | 6085 | #else /* CONFIG_TRACE_EVAL_MAP_FILE */ |
f57a4143 JL |
6086 | static inline void trace_create_eval_file(struct dentry *d_tracer) { } |
6087 | static inline void trace_insert_eval_map_file(struct module *mod, | |
00f4b652 | 6088 | struct trace_eval_map **start, int len) { } |
681bec03 | 6089 | #endif /* !CONFIG_TRACE_EVAL_MAP_FILE */ |
9828413d | 6090 | |
f57a4143 | 6091 | static void trace_insert_eval_map(struct module *mod, |
00f4b652 | 6092 | struct trace_eval_map **start, int len) |
0c564a53 | 6093 | { |
00f4b652 | 6094 | struct trace_eval_map **map; |
0c564a53 SRRH |
6095 | |
6096 | if (len <= 0) | |
6097 | return; | |
6098 | ||
6099 | map = start; | |
6100 | ||
f57a4143 | 6101 | trace_event_eval_update(map, len); |
9828413d | 6102 | |
f57a4143 | 6103 | trace_insert_eval_map_file(mod, start, len); |
0c564a53 SRRH |
6104 | } |
6105 | ||
bc0c38d1 SR |
6106 | static ssize_t |
6107 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
6108 | size_t cnt, loff_t *ppos) | |
6109 | { | |
2b6080f2 | 6110 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 6111 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
6112 | int r; |
6113 | ||
6114 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 6115 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
6116 | mutex_unlock(&trace_types_lock); |
6117 | ||
4bf39a94 | 6118 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
6119 | } |
6120 | ||
b6f11df2 ACM |
6121 | int tracer_init(struct tracer *t, struct trace_array *tr) |
6122 | { | |
1c5eb448 | 6123 | tracing_reset_online_cpus(&tr->array_buffer); |
b6f11df2 ACM |
6124 | return t->init(tr); |
6125 | } | |
6126 | ||
1c5eb448 | 6127 | static void set_buffer_entries(struct array_buffer *buf, unsigned long val) |
438ced17 VN |
6128 | { |
6129 | int cpu; | |
737223fb | 6130 | |
438ced17 | 6131 | for_each_tracing_cpu(cpu) |
12883efb | 6132 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
6133 | } |
6134 | ||
12883efb | 6135 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 6136 | /* resize @tr's buffer to the size of @size_tr's entries */ |
1c5eb448 SRV |
6137 | static int resize_buffer_duplicate_size(struct array_buffer *trace_buf, |
6138 | struct array_buffer *size_buf, int cpu_id) | |
d60da506 HT |
6139 | { |
6140 | int cpu, ret = 0; | |
6141 | ||
6142 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
6143 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
6144 | ret = ring_buffer_resize(trace_buf->buffer, |
6145 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
6146 | if (ret < 0) |
6147 | break; | |
12883efb SRRH |
6148 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
6149 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
6150 | } |
6151 | } else { | |
12883efb SRRH |
6152 | ret = ring_buffer_resize(trace_buf->buffer, |
6153 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 6154 | if (ret == 0) |
12883efb SRRH |
6155 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
6156 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
6157 | } |
6158 | ||
6159 | return ret; | |
6160 | } | |
12883efb | 6161 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 6162 | |
2b6080f2 SR |
6163 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
6164 | unsigned long size, int cpu) | |
73c5162a SR |
6165 | { |
6166 | int ret; | |
6167 | ||
6168 | /* | |
6169 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
6170 | * we use the size that was given, and we can forget about |
6171 | * expanding it later. | |
73c5162a | 6172 | */ |
55034cd6 | 6173 | ring_buffer_expanded = true; |
73c5162a | 6174 | |
b382ede6 | 6175 | /* May be called before buffers are initialized */ |
1c5eb448 | 6176 | if (!tr->array_buffer.buffer) |
b382ede6 SR |
6177 | return 0; |
6178 | ||
1c5eb448 | 6179 | ret = ring_buffer_resize(tr->array_buffer.buffer, size, cpu); |
73c5162a SR |
6180 | if (ret < 0) |
6181 | return ret; | |
6182 | ||
12883efb | 6183 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
6184 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
6185 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
6186 | goto out; |
6187 | ||
12883efb | 6188 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 6189 | if (ret < 0) { |
1c5eb448 SRV |
6190 | int r = resize_buffer_duplicate_size(&tr->array_buffer, |
6191 | &tr->array_buffer, cpu); | |
73c5162a | 6192 | if (r < 0) { |
a123c52b SR |
6193 | /* |
6194 | * AARGH! We are left with different | |
6195 | * size max buffer!!!! | |
6196 | * The max buffer is our "snapshot" buffer. | |
6197 | * When a tracer needs a snapshot (one of the | |
6198 | * latency tracers), it swaps the max buffer | |
6199 | * with the saved snap shot. We succeeded to | |
6200 | * update the size of the main buffer, but failed to | |
6201 | * update the size of the max buffer. But when we tried | |
6202 | * to reset the main buffer to the original size, we | |
6203 | * failed there too. This is very unlikely to | |
6204 | * happen, but if it does, warn and kill all | |
6205 | * tracing. | |
6206 | */ | |
73c5162a SR |
6207 | WARN_ON(1); |
6208 | tracing_disabled = 1; | |
6209 | } | |
6210 | return ret; | |
6211 | } | |
6212 | ||
438ced17 | 6213 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 6214 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 6215 | else |
12883efb | 6216 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 6217 | |
ef710e10 | 6218 | out: |
12883efb SRRH |
6219 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
6220 | ||
438ced17 | 6221 | if (cpu == RING_BUFFER_ALL_CPUS) |
1c5eb448 | 6222 | set_buffer_entries(&tr->array_buffer, size); |
438ced17 | 6223 | else |
1c5eb448 | 6224 | per_cpu_ptr(tr->array_buffer.data, cpu)->entries = size; |
73c5162a SR |
6225 | |
6226 | return ret; | |
6227 | } | |
6228 | ||
9c5b9d3d MH |
6229 | ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
6230 | unsigned long size, int cpu_id) | |
4f271a2a | 6231 | { |
08b0c9b4 | 6232 | int ret; |
4f271a2a VN |
6233 | |
6234 | mutex_lock(&trace_types_lock); | |
6235 | ||
438ced17 VN |
6236 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
6237 | /* make sure, this cpu is enabled in the mask */ | |
6238 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
6239 | ret = -EINVAL; | |
6240 | goto out; | |
6241 | } | |
6242 | } | |
4f271a2a | 6243 | |
2b6080f2 | 6244 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
6245 | if (ret < 0) |
6246 | ret = -ENOMEM; | |
6247 | ||
438ced17 | 6248 | out: |
4f271a2a VN |
6249 | mutex_unlock(&trace_types_lock); |
6250 | ||
6251 | return ret; | |
6252 | } | |
6253 | ||
ef710e10 | 6254 | |
1852fcce SR |
6255 | /** |
6256 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
6257 | * | |
6258 | * To save on memory when the tracing is never used on a system with it | |
6259 | * configured in. The ring buffers are set to a minimum size. But once | |
6260 | * a user starts to use the tracing facility, then they need to grow | |
6261 | * to their default size. | |
6262 | * | |
6263 | * This function is to be called when a tracer is about to be used. | |
6264 | */ | |
6265 | int tracing_update_buffers(void) | |
6266 | { | |
6267 | int ret = 0; | |
6268 | ||
1027fcb2 | 6269 | mutex_lock(&trace_types_lock); |
1852fcce | 6270 | if (!ring_buffer_expanded) |
2b6080f2 | 6271 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 6272 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 6273 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
6274 | |
6275 | return ret; | |
6276 | } | |
6277 | ||
577b785f SR |
6278 | struct trace_option_dentry; |
6279 | ||
37aea98b | 6280 | static void |
2b6080f2 | 6281 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f | 6282 | |
6b450d25 SRRH |
6283 | /* |
6284 | * Used to clear out the tracer before deletion of an instance. | |
6285 | * Must have trace_types_lock held. | |
6286 | */ | |
6287 | static void tracing_set_nop(struct trace_array *tr) | |
6288 | { | |
6289 | if (tr->current_trace == &nop_trace) | |
6290 | return; | |
6291 | ||
50512ab5 | 6292 | tr->current_trace->enabled--; |
6b450d25 SRRH |
6293 | |
6294 | if (tr->current_trace->reset) | |
6295 | tr->current_trace->reset(tr); | |
6296 | ||
6297 | tr->current_trace = &nop_trace; | |
6298 | } | |
6299 | ||
41d9c0be | 6300 | static void add_tracer_options(struct trace_array *tr, struct tracer *t) |
bc0c38d1 | 6301 | { |
09d23a1d SRRH |
6302 | /* Only enable if the directory has been created already. */ |
6303 | if (!tr->dir) | |
6304 | return; | |
6305 | ||
37aea98b | 6306 | create_trace_option_files(tr, t); |
09d23a1d SRRH |
6307 | } |
6308 | ||
9c5b9d3d | 6309 | int tracing_set_tracer(struct trace_array *tr, const char *buf) |
09d23a1d | 6310 | { |
bc0c38d1 | 6311 | struct tracer *t; |
12883efb | 6312 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 6313 | bool had_max_tr; |
12883efb | 6314 | #endif |
d9e54076 | 6315 | int ret = 0; |
bc0c38d1 | 6316 | |
1027fcb2 SR |
6317 | mutex_lock(&trace_types_lock); |
6318 | ||
73c5162a | 6319 | if (!ring_buffer_expanded) { |
2b6080f2 | 6320 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 6321 | RING_BUFFER_ALL_CPUS); |
73c5162a | 6322 | if (ret < 0) |
59f586db | 6323 | goto out; |
73c5162a SR |
6324 | ret = 0; |
6325 | } | |
6326 | ||
bc0c38d1 SR |
6327 | for (t = trace_types; t; t = t->next) { |
6328 | if (strcmp(t->name, buf) == 0) | |
6329 | break; | |
6330 | } | |
c2931e05 FW |
6331 | if (!t) { |
6332 | ret = -EINVAL; | |
6333 | goto out; | |
6334 | } | |
2b6080f2 | 6335 | if (t == tr->current_trace) |
bc0c38d1 SR |
6336 | goto out; |
6337 | ||
a35873a0 TZ |
6338 | #ifdef CONFIG_TRACER_SNAPSHOT |
6339 | if (t->use_max_tr) { | |
6340 | arch_spin_lock(&tr->max_lock); | |
6341 | if (tr->cond_snapshot) | |
6342 | ret = -EBUSY; | |
6343 | arch_spin_unlock(&tr->max_lock); | |
6344 | if (ret) | |
6345 | goto out; | |
6346 | } | |
6347 | #endif | |
c7b3ae0b ZSZ |
6348 | /* Some tracers won't work on kernel command line */ |
6349 | if (system_state < SYSTEM_RUNNING && t->noboot) { | |
6350 | pr_warn("Tracer '%s' is not allowed on command line, ignored\n", | |
6351 | t->name); | |
6352 | goto out; | |
6353 | } | |
6354 | ||
607e2ea1 SRRH |
6355 | /* Some tracers are only allowed for the top level buffer */ |
6356 | if (!trace_ok_for_array(t, tr)) { | |
6357 | ret = -EINVAL; | |
6358 | goto out; | |
6359 | } | |
6360 | ||
cf6ab6d9 | 6361 | /* If trace pipe files are being read, we can't change the tracer */ |
7ef282e0 | 6362 | if (tr->trace_ref) { |
cf6ab6d9 SRRH |
6363 | ret = -EBUSY; |
6364 | goto out; | |
6365 | } | |
6366 | ||
9f029e83 | 6367 | trace_branch_disable(); |
613f04a0 | 6368 | |
50512ab5 | 6369 | tr->current_trace->enabled--; |
613f04a0 | 6370 | |
2b6080f2 SR |
6371 | if (tr->current_trace->reset) |
6372 | tr->current_trace->reset(tr); | |
34600f0e | 6373 | |
74401729 | 6374 | /* Current trace needs to be nop_trace before synchronize_rcu */ |
2b6080f2 | 6375 | tr->current_trace = &nop_trace; |
34600f0e | 6376 | |
45ad21ca SRRH |
6377 | #ifdef CONFIG_TRACER_MAX_TRACE |
6378 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
6379 | |
6380 | if (had_max_tr && !t->use_max_tr) { | |
6381 | /* | |
6382 | * We need to make sure that the update_max_tr sees that | |
6383 | * current_trace changed to nop_trace to keep it from | |
6384 | * swapping the buffers after we resize it. | |
6385 | * The update_max_tr is called from interrupts disabled | |
6386 | * so a synchronized_sched() is sufficient. | |
6387 | */ | |
74401729 | 6388 | synchronize_rcu(); |
3209cff4 | 6389 | free_snapshot(tr); |
ef710e10 | 6390 | } |
12883efb | 6391 | #endif |
12883efb SRRH |
6392 | |
6393 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 6394 | if (t->use_max_tr && !had_max_tr) { |
2824f503 | 6395 | ret = tracing_alloc_snapshot_instance(tr); |
d60da506 HT |
6396 | if (ret < 0) |
6397 | goto out; | |
ef710e10 | 6398 | } |
12883efb | 6399 | #endif |
577b785f | 6400 | |
1c80025a | 6401 | if (t->init) { |
b6f11df2 | 6402 | ret = tracer_init(t, tr); |
1c80025a FW |
6403 | if (ret) |
6404 | goto out; | |
6405 | } | |
bc0c38d1 | 6406 | |
2b6080f2 | 6407 | tr->current_trace = t; |
50512ab5 | 6408 | tr->current_trace->enabled++; |
9f029e83 | 6409 | trace_branch_enable(tr); |
bc0c38d1 SR |
6410 | out: |
6411 | mutex_unlock(&trace_types_lock); | |
6412 | ||
d9e54076 PZ |
6413 | return ret; |
6414 | } | |
6415 | ||
6416 | static ssize_t | |
6417 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
6418 | size_t cnt, loff_t *ppos) | |
6419 | { | |
607e2ea1 | 6420 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 6421 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
6422 | int i; |
6423 | size_t ret; | |
e6e7a65a FW |
6424 | int err; |
6425 | ||
6426 | ret = cnt; | |
d9e54076 | 6427 | |
ee6c2c1b LZ |
6428 | if (cnt > MAX_TRACER_SIZE) |
6429 | cnt = MAX_TRACER_SIZE; | |
d9e54076 | 6430 | |
4afe6495 | 6431 | if (copy_from_user(buf, ubuf, cnt)) |
d9e54076 PZ |
6432 | return -EFAULT; |
6433 | ||
6434 | buf[cnt] = 0; | |
6435 | ||
6436 | /* strip ending whitespace. */ | |
6437 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
6438 | buf[i] = 0; | |
6439 | ||
607e2ea1 | 6440 | err = tracing_set_tracer(tr, buf); |
e6e7a65a FW |
6441 | if (err) |
6442 | return err; | |
d9e54076 | 6443 | |
cf8517cf | 6444 | *ppos += ret; |
bc0c38d1 | 6445 | |
c2931e05 | 6446 | return ret; |
bc0c38d1 SR |
6447 | } |
6448 | ||
6449 | static ssize_t | |
6508fa76 SF |
6450 | tracing_nsecs_read(unsigned long *ptr, char __user *ubuf, |
6451 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 6452 | { |
bc0c38d1 SR |
6453 | char buf[64]; |
6454 | int r; | |
6455 | ||
cffae437 | 6456 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 6457 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
6458 | if (r > sizeof(buf)) |
6459 | r = sizeof(buf); | |
4bf39a94 | 6460 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
6461 | } |
6462 | ||
6463 | static ssize_t | |
6508fa76 SF |
6464 | tracing_nsecs_write(unsigned long *ptr, const char __user *ubuf, |
6465 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 6466 | { |
5e39841c | 6467 | unsigned long val; |
c6caeeb1 | 6468 | int ret; |
bc0c38d1 | 6469 | |
22fe9b54 PH |
6470 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
6471 | if (ret) | |
c6caeeb1 | 6472 | return ret; |
bc0c38d1 SR |
6473 | |
6474 | *ptr = val * 1000; | |
6475 | ||
6476 | return cnt; | |
6477 | } | |
6478 | ||
6508fa76 SF |
6479 | static ssize_t |
6480 | tracing_thresh_read(struct file *filp, char __user *ubuf, | |
6481 | size_t cnt, loff_t *ppos) | |
6482 | { | |
6483 | return tracing_nsecs_read(&tracing_thresh, ubuf, cnt, ppos); | |
6484 | } | |
6485 | ||
6486 | static ssize_t | |
6487 | tracing_thresh_write(struct file *filp, const char __user *ubuf, | |
6488 | size_t cnt, loff_t *ppos) | |
6489 | { | |
6490 | struct trace_array *tr = filp->private_data; | |
6491 | int ret; | |
6492 | ||
6493 | mutex_lock(&trace_types_lock); | |
6494 | ret = tracing_nsecs_write(&tracing_thresh, ubuf, cnt, ppos); | |
6495 | if (ret < 0) | |
6496 | goto out; | |
6497 | ||
6498 | if (tr->current_trace->update_thresh) { | |
6499 | ret = tr->current_trace->update_thresh(tr); | |
6500 | if (ret < 0) | |
6501 | goto out; | |
6502 | } | |
6503 | ||
6504 | ret = cnt; | |
6505 | out: | |
6506 | mutex_unlock(&trace_types_lock); | |
6507 | ||
6508 | return ret; | |
6509 | } | |
6510 | ||
f971cc9a | 6511 | #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) |
e428abbb | 6512 | |
6508fa76 SF |
6513 | static ssize_t |
6514 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
6515 | size_t cnt, loff_t *ppos) | |
6516 | { | |
6517 | return tracing_nsecs_read(filp->private_data, ubuf, cnt, ppos); | |
6518 | } | |
6519 | ||
6520 | static ssize_t | |
6521 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
6522 | size_t cnt, loff_t *ppos) | |
6523 | { | |
6524 | return tracing_nsecs_write(filp->private_data, ubuf, cnt, ppos); | |
6525 | } | |
6526 | ||
e428abbb CG |
6527 | #endif |
6528 | ||
b3806b43 SR |
6529 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
6530 | { | |
15544209 | 6531 | struct trace_array *tr = inode->i_private; |
b3806b43 | 6532 | struct trace_iterator *iter; |
8530dec6 | 6533 | int ret; |
b3806b43 | 6534 | |
8530dec6 SRV |
6535 | ret = tracing_check_open_get_tr(tr); |
6536 | if (ret) | |
6537 | return ret; | |
7b85af63 | 6538 | |
b04cc6b1 FW |
6539 | mutex_lock(&trace_types_lock); |
6540 | ||
b3806b43 SR |
6541 | /* create a buffer to store the information to pass to userspace */ |
6542 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
6543 | if (!iter) { |
6544 | ret = -ENOMEM; | |
f77d09a3 | 6545 | __trace_array_put(tr); |
b04cc6b1 FW |
6546 | goto out; |
6547 | } | |
b3806b43 | 6548 | |
3a161d99 | 6549 | trace_seq_init(&iter->seq); |
d716ff71 | 6550 | iter->trace = tr->current_trace; |
d7350c3f | 6551 | |
4462344e | 6552 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 6553 | ret = -ENOMEM; |
d7350c3f | 6554 | goto fail; |
4462344e RR |
6555 | } |
6556 | ||
a309720c | 6557 | /* trace pipe does not show start of buffer */ |
4462344e | 6558 | cpumask_setall(iter->started); |
a309720c | 6559 | |
983f938a | 6560 | if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) |
112f38a7 SR |
6561 | iter->iter_flags |= TRACE_FILE_LAT_FMT; |
6562 | ||
8be0709f | 6563 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 6564 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
6565 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
6566 | ||
15544209 | 6567 | iter->tr = tr; |
1c5eb448 | 6568 | iter->array_buffer = &tr->array_buffer; |
15544209 | 6569 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 6570 | mutex_init(&iter->mutex); |
b3806b43 SR |
6571 | filp->private_data = iter; |
6572 | ||
107bad8b SR |
6573 | if (iter->trace->pipe_open) |
6574 | iter->trace->pipe_open(iter); | |
107bad8b | 6575 | |
b444786f | 6576 | nonseekable_open(inode, filp); |
cf6ab6d9 | 6577 | |
7ef282e0 | 6578 | tr->trace_ref++; |
b04cc6b1 FW |
6579 | out: |
6580 | mutex_unlock(&trace_types_lock); | |
6581 | return ret; | |
d7350c3f FW |
6582 | |
6583 | fail: | |
d7350c3f | 6584 | kfree(iter); |
7b85af63 | 6585 | __trace_array_put(tr); |
d7350c3f FW |
6586 | mutex_unlock(&trace_types_lock); |
6587 | return ret; | |
b3806b43 SR |
6588 | } |
6589 | ||
6590 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
6591 | { | |
6592 | struct trace_iterator *iter = file->private_data; | |
15544209 | 6593 | struct trace_array *tr = inode->i_private; |
b3806b43 | 6594 | |
b04cc6b1 FW |
6595 | mutex_lock(&trace_types_lock); |
6596 | ||
7ef282e0 | 6597 | tr->trace_ref--; |
cf6ab6d9 | 6598 | |
29bf4a5e | 6599 | if (iter->trace->pipe_close) |
c521efd1 SR |
6600 | iter->trace->pipe_close(iter); |
6601 | ||
b04cc6b1 FW |
6602 | mutex_unlock(&trace_types_lock); |
6603 | ||
4462344e | 6604 | free_cpumask_var(iter->started); |
d7350c3f | 6605 | mutex_destroy(&iter->mutex); |
b3806b43 | 6606 | kfree(iter); |
b3806b43 | 6607 | |
7b85af63 SRRH |
6608 | trace_array_put(tr); |
6609 | ||
b3806b43 SR |
6610 | return 0; |
6611 | } | |
6612 | ||
9dd95748 | 6613 | static __poll_t |
cc60cdc9 | 6614 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 6615 | { |
983f938a SRRH |
6616 | struct trace_array *tr = iter->tr; |
6617 | ||
15693458 SRRH |
6618 | /* Iterators are static, they should be filled or empty */ |
6619 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
a9a08845 | 6620 | return EPOLLIN | EPOLLRDNORM; |
2a2cc8f7 | 6621 | |
983f938a | 6622 | if (tr->trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
6623 | /* |
6624 | * Always select as readable when in blocking mode | |
6625 | */ | |
a9a08845 | 6626 | return EPOLLIN | EPOLLRDNORM; |
15693458 | 6627 | else |
1c5eb448 | 6628 | return ring_buffer_poll_wait(iter->array_buffer->buffer, iter->cpu_file, |
15693458 | 6629 | filp, poll_table); |
2a2cc8f7 | 6630 | } |
2a2cc8f7 | 6631 | |
9dd95748 | 6632 | static __poll_t |
cc60cdc9 SR |
6633 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) |
6634 | { | |
6635 | struct trace_iterator *iter = filp->private_data; | |
6636 | ||
6637 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
6638 | } |
6639 | ||
d716ff71 | 6640 | /* Must be called with iter->mutex held. */ |
ff98781b | 6641 | static int tracing_wait_pipe(struct file *filp) |
b3806b43 SR |
6642 | { |
6643 | struct trace_iterator *iter = filp->private_data; | |
8b8b3683 | 6644 | int ret; |
b3806b43 | 6645 | |
b3806b43 | 6646 | while (trace_empty(iter)) { |
2dc8f095 | 6647 | |
107bad8b | 6648 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 6649 | return -EAGAIN; |
107bad8b | 6650 | } |
2dc8f095 | 6651 | |
b3806b43 | 6652 | /* |
250bfd3d | 6653 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
6654 | * We still block if tracing is disabled, but we have never |
6655 | * read anything. This allows a user to cat this file, and | |
6656 | * then enable tracing. But after we have read something, | |
6657 | * we give an EOF when tracing is again disabled. | |
6658 | * | |
6659 | * iter->pos will be 0 if we haven't read anything. | |
6660 | */ | |
75df6e68 | 6661 | if (!tracer_tracing_is_on(iter->tr) && iter->pos) |
b3806b43 | 6662 | break; |
f4874261 SRRH |
6663 | |
6664 | mutex_unlock(&iter->mutex); | |
6665 | ||
2c2b0a78 | 6666 | ret = wait_on_pipe(iter, 0); |
f4874261 SRRH |
6667 | |
6668 | mutex_lock(&iter->mutex); | |
6669 | ||
8b8b3683 SRRH |
6670 | if (ret) |
6671 | return ret; | |
b3806b43 SR |
6672 | } |
6673 | ||
ff98781b EGM |
6674 | return 1; |
6675 | } | |
6676 | ||
6677 | /* | |
6678 | * Consumer reader. | |
6679 | */ | |
6680 | static ssize_t | |
6681 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
6682 | size_t cnt, loff_t *ppos) | |
6683 | { | |
6684 | struct trace_iterator *iter = filp->private_data; | |
6685 | ssize_t sret; | |
6686 | ||
d7350c3f FW |
6687 | /* |
6688 | * Avoid more than one consumer on a single file descriptor | |
6689 | * This is just a matter of traces coherency, the ring buffer itself | |
6690 | * is protected. | |
6691 | */ | |
6692 | mutex_lock(&iter->mutex); | |
1245800c SRRH |
6693 | |
6694 | /* return any leftover data */ | |
6695 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
6696 | if (sret != -EBUSY) | |
6697 | goto out; | |
6698 | ||
6699 | trace_seq_init(&iter->seq); | |
6700 | ||
ff98781b EGM |
6701 | if (iter->trace->read) { |
6702 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
6703 | if (sret) | |
6704 | goto out; | |
6705 | } | |
6706 | ||
6707 | waitagain: | |
6708 | sret = tracing_wait_pipe(filp); | |
6709 | if (sret <= 0) | |
6710 | goto out; | |
6711 | ||
b3806b43 | 6712 | /* stop when tracing is finished */ |
ff98781b EGM |
6713 | if (trace_empty(iter)) { |
6714 | sret = 0; | |
107bad8b | 6715 | goto out; |
ff98781b | 6716 | } |
b3806b43 SR |
6717 | |
6718 | if (cnt >= PAGE_SIZE) | |
6719 | cnt = PAGE_SIZE - 1; | |
6720 | ||
53d0aa77 | 6721 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
6722 | memset(&iter->seq, 0, |
6723 | sizeof(struct trace_iterator) - | |
6724 | offsetof(struct trace_iterator, seq)); | |
ed5467da | 6725 | cpumask_clear(iter->started); |
d303de1f | 6726 | trace_seq_init(&iter->seq); |
4823ed7e | 6727 | iter->pos = -1; |
b3806b43 | 6728 | |
4f535968 | 6729 | trace_event_read_lock(); |
7e53bd42 | 6730 | trace_access_lock(iter->cpu_file); |
955b61e5 | 6731 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 6732 | enum print_line_t ret; |
5ac48378 | 6733 | int save_len = iter->seq.seq.len; |
088b1e42 | 6734 | |
f9896bf3 | 6735 | ret = print_trace_line(iter); |
2c4f035f | 6736 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 | 6737 | /* don't print partial lines */ |
5ac48378 | 6738 | iter->seq.seq.len = save_len; |
b3806b43 | 6739 | break; |
088b1e42 | 6740 | } |
b91facc3 FW |
6741 | if (ret != TRACE_TYPE_NO_CONSUME) |
6742 | trace_consume(iter); | |
b3806b43 | 6743 | |
5ac48378 | 6744 | if (trace_seq_used(&iter->seq) >= cnt) |
b3806b43 | 6745 | break; |
ee5e51f5 JO |
6746 | |
6747 | /* | |
6748 | * Setting the full flag means we reached the trace_seq buffer | |
6749 | * size and we should leave by partial output condition above. | |
6750 | * One of the trace_seq_* functions is not used properly. | |
6751 | */ | |
6752 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
6753 | iter->ent->type); | |
b3806b43 | 6754 | } |
7e53bd42 | 6755 | trace_access_unlock(iter->cpu_file); |
4f535968 | 6756 | trace_event_read_unlock(); |
b3806b43 | 6757 | |
b3806b43 | 6758 | /* Now copy what we have to the user */ |
6c6c2796 | 6759 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
5ac48378 | 6760 | if (iter->seq.seq.readpos >= trace_seq_used(&iter->seq)) |
f9520750 | 6761 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
6762 | |
6763 | /* | |
25985edc | 6764 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
6765 | * entries, go back to wait for more entries. |
6766 | */ | |
6c6c2796 | 6767 | if (sret == -EBUSY) |
9ff4b974 | 6768 | goto waitagain; |
b3806b43 | 6769 | |
107bad8b | 6770 | out: |
d7350c3f | 6771 | mutex_unlock(&iter->mutex); |
107bad8b | 6772 | |
6c6c2796 | 6773 | return sret; |
b3806b43 SR |
6774 | } |
6775 | ||
3c56819b EGM |
6776 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, |
6777 | unsigned int idx) | |
6778 | { | |
6779 | __free_page(spd->pages[idx]); | |
6780 | } | |
6781 | ||
34cd4998 | 6782 | static size_t |
fa7c7f6e | 6783 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
6784 | { |
6785 | size_t count; | |
74f06bb7 | 6786 | int save_len; |
34cd4998 SR |
6787 | int ret; |
6788 | ||
6789 | /* Seq buffer is page-sized, exactly what we need. */ | |
6790 | for (;;) { | |
74f06bb7 | 6791 | save_len = iter->seq.seq.len; |
34cd4998 | 6792 | ret = print_trace_line(iter); |
74f06bb7 SRRH |
6793 | |
6794 | if (trace_seq_has_overflowed(&iter->seq)) { | |
6795 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
6796 | break; |
6797 | } | |
74f06bb7 SRRH |
6798 | |
6799 | /* | |
6800 | * This should not be hit, because it should only | |
6801 | * be set if the iter->seq overflowed. But check it | |
6802 | * anyway to be safe. | |
6803 | */ | |
34cd4998 | 6804 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
74f06bb7 SRRH |
6805 | iter->seq.seq.len = save_len; |
6806 | break; | |
6807 | } | |
6808 | ||
5ac48378 | 6809 | count = trace_seq_used(&iter->seq) - save_len; |
74f06bb7 SRRH |
6810 | if (rem < count) { |
6811 | rem = 0; | |
6812 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
6813 | break; |
6814 | } | |
6815 | ||
74e7ff8c LJ |
6816 | if (ret != TRACE_TYPE_NO_CONSUME) |
6817 | trace_consume(iter); | |
34cd4998 | 6818 | rem -= count; |
955b61e5 | 6819 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
6820 | rem = 0; |
6821 | iter->ent = NULL; | |
6822 | break; | |
6823 | } | |
6824 | } | |
6825 | ||
6826 | return rem; | |
6827 | } | |
6828 | ||
3c56819b EGM |
6829 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
6830 | loff_t *ppos, | |
6831 | struct pipe_inode_info *pipe, | |
6832 | size_t len, | |
6833 | unsigned int flags) | |
6834 | { | |
35f3d14d JA |
6835 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
6836 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
6837 | struct trace_iterator *iter = filp->private_data; |
6838 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
6839 | .pages = pages_def, |
6840 | .partial = partial_def, | |
34cd4998 | 6841 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 6842 | .nr_pages_max = PIPE_DEF_BUFFERS, |
6797d97a | 6843 | .ops = &default_pipe_buf_ops, |
34cd4998 | 6844 | .spd_release = tracing_spd_release_pipe, |
3c56819b EGM |
6845 | }; |
6846 | ssize_t ret; | |
34cd4998 | 6847 | size_t rem; |
3c56819b EGM |
6848 | unsigned int i; |
6849 | ||
35f3d14d JA |
6850 | if (splice_grow_spd(pipe, &spd)) |
6851 | return -ENOMEM; | |
6852 | ||
d7350c3f | 6853 | mutex_lock(&iter->mutex); |
3c56819b EGM |
6854 | |
6855 | if (iter->trace->splice_read) { | |
6856 | ret = iter->trace->splice_read(iter, filp, | |
6857 | ppos, pipe, len, flags); | |
6858 | if (ret) | |
34cd4998 | 6859 | goto out_err; |
3c56819b EGM |
6860 | } |
6861 | ||
6862 | ret = tracing_wait_pipe(filp); | |
6863 | if (ret <= 0) | |
34cd4998 | 6864 | goto out_err; |
3c56819b | 6865 | |
955b61e5 | 6866 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 6867 | ret = -EFAULT; |
34cd4998 | 6868 | goto out_err; |
3c56819b EGM |
6869 | } |
6870 | ||
4f535968 | 6871 | trace_event_read_lock(); |
7e53bd42 | 6872 | trace_access_lock(iter->cpu_file); |
4f535968 | 6873 | |
3c56819b | 6874 | /* Fill as many pages as possible. */ |
a786c06d | 6875 | for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) { |
35f3d14d JA |
6876 | spd.pages[i] = alloc_page(GFP_KERNEL); |
6877 | if (!spd.pages[i]) | |
34cd4998 | 6878 | break; |
3c56819b | 6879 | |
fa7c7f6e | 6880 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
6881 | |
6882 | /* Copy the data into the page, so we can start over. */ | |
6883 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 6884 | page_address(spd.pages[i]), |
5ac48378 | 6885 | trace_seq_used(&iter->seq)); |
3c56819b | 6886 | if (ret < 0) { |
35f3d14d | 6887 | __free_page(spd.pages[i]); |
3c56819b EGM |
6888 | break; |
6889 | } | |
35f3d14d | 6890 | spd.partial[i].offset = 0; |
5ac48378 | 6891 | spd.partial[i].len = trace_seq_used(&iter->seq); |
3c56819b | 6892 | |
f9520750 | 6893 | trace_seq_init(&iter->seq); |
3c56819b EGM |
6894 | } |
6895 | ||
7e53bd42 | 6896 | trace_access_unlock(iter->cpu_file); |
4f535968 | 6897 | trace_event_read_unlock(); |
d7350c3f | 6898 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
6899 | |
6900 | spd.nr_pages = i; | |
6901 | ||
a29054d9 SRRH |
6902 | if (i) |
6903 | ret = splice_to_pipe(pipe, &spd); | |
6904 | else | |
6905 | ret = 0; | |
35f3d14d | 6906 | out: |
047fe360 | 6907 | splice_shrink_spd(&spd); |
35f3d14d | 6908 | return ret; |
3c56819b | 6909 | |
34cd4998 | 6910 | out_err: |
d7350c3f | 6911 | mutex_unlock(&iter->mutex); |
35f3d14d | 6912 | goto out; |
3c56819b EGM |
6913 | } |
6914 | ||
a98a3c3f SR |
6915 | static ssize_t |
6916 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
6917 | size_t cnt, loff_t *ppos) | |
6918 | { | |
0bc392ee ON |
6919 | struct inode *inode = file_inode(filp); |
6920 | struct trace_array *tr = inode->i_private; | |
6921 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
6922 | char buf[64]; |
6923 | int r = 0; | |
6924 | ssize_t ret; | |
a98a3c3f | 6925 | |
db526ca3 | 6926 | mutex_lock(&trace_types_lock); |
438ced17 | 6927 | |
0bc392ee | 6928 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
6929 | int cpu, buf_size_same; |
6930 | unsigned long size; | |
6931 | ||
6932 | size = 0; | |
6933 | buf_size_same = 1; | |
6934 | /* check if all cpu sizes are same */ | |
6935 | for_each_tracing_cpu(cpu) { | |
6936 | /* fill in the size from first enabled cpu */ | |
6937 | if (size == 0) | |
1c5eb448 SRV |
6938 | size = per_cpu_ptr(tr->array_buffer.data, cpu)->entries; |
6939 | if (size != per_cpu_ptr(tr->array_buffer.data, cpu)->entries) { | |
438ced17 VN |
6940 | buf_size_same = 0; |
6941 | break; | |
6942 | } | |
6943 | } | |
6944 | ||
6945 | if (buf_size_same) { | |
6946 | if (!ring_buffer_expanded) | |
6947 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
6948 | size >> 10, | |
6949 | trace_buf_size >> 10); | |
6950 | else | |
6951 | r = sprintf(buf, "%lu\n", size >> 10); | |
6952 | } else | |
6953 | r = sprintf(buf, "X\n"); | |
6954 | } else | |
1c5eb448 | 6955 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->array_buffer.data, cpu)->entries >> 10); |
438ced17 | 6956 | |
db526ca3 SR |
6957 | mutex_unlock(&trace_types_lock); |
6958 | ||
438ced17 VN |
6959 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
6960 | return ret; | |
a98a3c3f SR |
6961 | } |
6962 | ||
6963 | static ssize_t | |
6964 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
6965 | size_t cnt, loff_t *ppos) | |
6966 | { | |
0bc392ee ON |
6967 | struct inode *inode = file_inode(filp); |
6968 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 6969 | unsigned long val; |
4f271a2a | 6970 | int ret; |
a98a3c3f | 6971 | |
22fe9b54 PH |
6972 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
6973 | if (ret) | |
c6caeeb1 | 6974 | return ret; |
a98a3c3f SR |
6975 | |
6976 | /* must have at least 1 entry */ | |
6977 | if (!val) | |
6978 | return -EINVAL; | |
6979 | ||
1696b2b0 SR |
6980 | /* value is in KB */ |
6981 | val <<= 10; | |
0bc392ee | 6982 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
6983 | if (ret < 0) |
6984 | return ret; | |
a98a3c3f | 6985 | |
cf8517cf | 6986 | *ppos += cnt; |
a98a3c3f | 6987 | |
4f271a2a VN |
6988 | return cnt; |
6989 | } | |
bf5e6519 | 6990 | |
f81ab074 VN |
6991 | static ssize_t |
6992 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
6993 | size_t cnt, loff_t *ppos) | |
6994 | { | |
6995 | struct trace_array *tr = filp->private_data; | |
6996 | char buf[64]; | |
6997 | int r, cpu; | |
6998 | unsigned long size = 0, expanded_size = 0; | |
6999 | ||
7000 | mutex_lock(&trace_types_lock); | |
7001 | for_each_tracing_cpu(cpu) { | |
1c5eb448 | 7002 | size += per_cpu_ptr(tr->array_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
7003 | if (!ring_buffer_expanded) |
7004 | expanded_size += trace_buf_size >> 10; | |
7005 | } | |
7006 | if (ring_buffer_expanded) | |
7007 | r = sprintf(buf, "%lu\n", size); | |
7008 | else | |
7009 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
7010 | mutex_unlock(&trace_types_lock); | |
7011 | ||
7012 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
7013 | } | |
7014 | ||
4f271a2a VN |
7015 | static ssize_t |
7016 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
7017 | size_t cnt, loff_t *ppos) | |
7018 | { | |
7019 | /* | |
7020 | * There is no need to read what the user has written, this function | |
7021 | * is just to make sure that there is no error when "echo" is used | |
7022 | */ | |
7023 | ||
7024 | *ppos += cnt; | |
a98a3c3f SR |
7025 | |
7026 | return cnt; | |
7027 | } | |
7028 | ||
4f271a2a VN |
7029 | static int |
7030 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
7031 | { | |
2b6080f2 SR |
7032 | struct trace_array *tr = inode->i_private; |
7033 | ||
cf30cf67 | 7034 | /* disable tracing ? */ |
983f938a | 7035 | if (tr->trace_flags & TRACE_ITER_STOP_ON_FREE) |
711e1243 | 7036 | tracer_tracing_off(tr); |
4f271a2a | 7037 | /* resize the ring buffer to 0 */ |
2b6080f2 | 7038 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 7039 | |
7b85af63 SRRH |
7040 | trace_array_put(tr); |
7041 | ||
4f271a2a VN |
7042 | return 0; |
7043 | } | |
7044 | ||
5bf9a1ee PP |
7045 | static ssize_t |
7046 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
7047 | size_t cnt, loff_t *fpos) | |
7048 | { | |
2d71619c | 7049 | struct trace_array *tr = filp->private_data; |
d696b58c | 7050 | struct ring_buffer_event *event; |
3dd80953 | 7051 | enum event_trigger_type tt = ETT_NONE; |
13292494 | 7052 | struct trace_buffer *buffer; |
d696b58c | 7053 | struct print_entry *entry; |
d696b58c | 7054 | ssize_t written; |
d696b58c SR |
7055 | int size; |
7056 | int len; | |
fa32e855 | 7057 | |
656c7f0d | 7058 | /* Used in tracing_mark_raw_write() as well */ |
0f5e5a3a RV |
7059 | #define FAULTED_STR "<faulted>" |
7060 | #define FAULTED_SIZE (sizeof(FAULTED_STR) - 1) /* '\0' is already accounted for */ | |
5bf9a1ee | 7061 | |
c76f0694 | 7062 | if (tracing_disabled) |
5bf9a1ee PP |
7063 | return -EINVAL; |
7064 | ||
983f938a | 7065 | if (!(tr->trace_flags & TRACE_ITER_MARKERS)) |
5224c3a3 MSB |
7066 | return -EINVAL; |
7067 | ||
5bf9a1ee PP |
7068 | if (cnt > TRACE_BUF_SIZE) |
7069 | cnt = TRACE_BUF_SIZE; | |
7070 | ||
d696b58c | 7071 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); |
5bf9a1ee | 7072 | |
656c7f0d | 7073 | size = sizeof(*entry) + cnt + 2; /* add '\0' and possible '\n' */ |
d696b58c | 7074 | |
656c7f0d SRRH |
7075 | /* If less than "<faulted>", then make sure we can still add that */ |
7076 | if (cnt < FAULTED_SIZE) | |
7077 | size += FAULTED_SIZE - cnt; | |
d696b58c | 7078 | |
1c5eb448 | 7079 | buffer = tr->array_buffer.buffer; |
3e9a8aad | 7080 | event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
36590c50 | 7081 | tracing_gen_ctx()); |
656c7f0d | 7082 | if (unlikely(!event)) |
d696b58c | 7083 | /* Ring buffer disabled, return as if not open for write */ |
656c7f0d | 7084 | return -EBADF; |
d696b58c SR |
7085 | |
7086 | entry = ring_buffer_event_data(event); | |
7087 | entry->ip = _THIS_IP_; | |
7088 | ||
656c7f0d SRRH |
7089 | len = __copy_from_user_inatomic(&entry->buf, ubuf, cnt); |
7090 | if (len) { | |
0f5e5a3a | 7091 | memcpy(&entry->buf, FAULTED_STR, FAULTED_SIZE); |
656c7f0d SRRH |
7092 | cnt = FAULTED_SIZE; |
7093 | written = -EFAULT; | |
c13d2f7c | 7094 | } else |
656c7f0d | 7095 | written = cnt; |
5bf9a1ee | 7096 | |
3dd80953 SRV |
7097 | if (tr->trace_marker_file && !list_empty(&tr->trace_marker_file->triggers)) { |
7098 | /* do not add \n before testing triggers, but add \0 */ | |
7099 | entry->buf[cnt] = '\0'; | |
b47e3302 | 7100 | tt = event_triggers_call(tr->trace_marker_file, buffer, entry, event); |
3dd80953 SRV |
7101 | } |
7102 | ||
d696b58c SR |
7103 | if (entry->buf[cnt - 1] != '\n') { |
7104 | entry->buf[cnt] = '\n'; | |
7105 | entry->buf[cnt + 1] = '\0'; | |
7106 | } else | |
7107 | entry->buf[cnt] = '\0'; | |
7108 | ||
458999c6 TZ |
7109 | if (static_branch_unlikely(&trace_marker_exports_enabled)) |
7110 | ftrace_exports(event, TRACE_EXPORT_MARKER); | |
7ffbd48d | 7111 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 7112 | |
3dd80953 SRV |
7113 | if (tt) |
7114 | event_triggers_post_call(tr->trace_marker_file, tt); | |
7115 | ||
656c7f0d SRRH |
7116 | if (written > 0) |
7117 | *fpos += written; | |
5bf9a1ee | 7118 | |
fa32e855 SR |
7119 | return written; |
7120 | } | |
7121 | ||
7122 | /* Limit it for now to 3K (including tag) */ | |
7123 | #define RAW_DATA_MAX_SIZE (1024*3) | |
7124 | ||
7125 | static ssize_t | |
7126 | tracing_mark_raw_write(struct file *filp, const char __user *ubuf, | |
7127 | size_t cnt, loff_t *fpos) | |
7128 | { | |
7129 | struct trace_array *tr = filp->private_data; | |
7130 | struct ring_buffer_event *event; | |
13292494 | 7131 | struct trace_buffer *buffer; |
fa32e855 | 7132 | struct raw_data_entry *entry; |
fa32e855 | 7133 | ssize_t written; |
fa32e855 SR |
7134 | int size; |
7135 | int len; | |
7136 | ||
656c7f0d SRRH |
7137 | #define FAULT_SIZE_ID (FAULTED_SIZE + sizeof(int)) |
7138 | ||
fa32e855 SR |
7139 | if (tracing_disabled) |
7140 | return -EINVAL; | |
7141 | ||
7142 | if (!(tr->trace_flags & TRACE_ITER_MARKERS)) | |
7143 | return -EINVAL; | |
7144 | ||
7145 | /* The marker must at least have a tag id */ | |
7146 | if (cnt < sizeof(unsigned int) || cnt > RAW_DATA_MAX_SIZE) | |
7147 | return -EINVAL; | |
7148 | ||
7149 | if (cnt > TRACE_BUF_SIZE) | |
7150 | cnt = TRACE_BUF_SIZE; | |
7151 | ||
7152 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
7153 | ||
fa32e855 | 7154 | size = sizeof(*entry) + cnt; |
656c7f0d SRRH |
7155 | if (cnt < FAULT_SIZE_ID) |
7156 | size += FAULT_SIZE_ID - cnt; | |
7157 | ||
1c5eb448 | 7158 | buffer = tr->array_buffer.buffer; |
3e9a8aad | 7159 | event = __trace_buffer_lock_reserve(buffer, TRACE_RAW_DATA, size, |
36590c50 | 7160 | tracing_gen_ctx()); |
656c7f0d | 7161 | if (!event) |
fa32e855 | 7162 | /* Ring buffer disabled, return as if not open for write */ |
656c7f0d | 7163 | return -EBADF; |
fa32e855 SR |
7164 | |
7165 | entry = ring_buffer_event_data(event); | |
7166 | ||
656c7f0d SRRH |
7167 | len = __copy_from_user_inatomic(&entry->id, ubuf, cnt); |
7168 | if (len) { | |
7169 | entry->id = -1; | |
0f5e5a3a | 7170 | memcpy(&entry->buf, FAULTED_STR, FAULTED_SIZE); |
656c7f0d | 7171 | written = -EFAULT; |
fa32e855 | 7172 | } else |
656c7f0d | 7173 | written = cnt; |
fa32e855 SR |
7174 | |
7175 | __buffer_unlock_commit(buffer, event); | |
7176 | ||
656c7f0d SRRH |
7177 | if (written > 0) |
7178 | *fpos += written; | |
1aa54bca MS |
7179 | |
7180 | return written; | |
5bf9a1ee PP |
7181 | } |
7182 | ||
13f16d20 | 7183 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 7184 | { |
2b6080f2 | 7185 | struct trace_array *tr = m->private; |
5079f326 Z |
7186 | int i; |
7187 | ||
7188 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 7189 | seq_printf(m, |
5079f326 | 7190 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
7191 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
7192 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 7193 | seq_putc(m, '\n'); |
5079f326 | 7194 | |
13f16d20 | 7195 | return 0; |
5079f326 Z |
7196 | } |
7197 | ||
d71bd34d | 7198 | int tracing_set_clock(struct trace_array *tr, const char *clockstr) |
5079f326 | 7199 | { |
5079f326 Z |
7200 | int i; |
7201 | ||
5079f326 Z |
7202 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { |
7203 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
7204 | break; | |
7205 | } | |
7206 | if (i == ARRAY_SIZE(trace_clocks)) | |
7207 | return -EINVAL; | |
7208 | ||
5079f326 Z |
7209 | mutex_lock(&trace_types_lock); |
7210 | ||
2b6080f2 SR |
7211 | tr->clock_id = i; |
7212 | ||
1c5eb448 | 7213 | ring_buffer_set_clock(tr->array_buffer.buffer, trace_clocks[i].func); |
5079f326 | 7214 | |
60303ed3 DS |
7215 | /* |
7216 | * New clock may not be consistent with the previous clock. | |
7217 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
7218 | */ | |
1c5eb448 | 7219 | tracing_reset_online_cpus(&tr->array_buffer); |
12883efb SRRH |
7220 | |
7221 | #ifdef CONFIG_TRACER_MAX_TRACE | |
170b3b10 | 7222 | if (tr->max_buffer.buffer) |
12883efb | 7223 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); |
9457158b | 7224 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 7225 | #endif |
60303ed3 | 7226 | |
5079f326 Z |
7227 | mutex_unlock(&trace_types_lock); |
7228 | ||
e1e232ca SR |
7229 | return 0; |
7230 | } | |
7231 | ||
7232 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
7233 | size_t cnt, loff_t *fpos) | |
7234 | { | |
7235 | struct seq_file *m = filp->private_data; | |
7236 | struct trace_array *tr = m->private; | |
7237 | char buf[64]; | |
7238 | const char *clockstr; | |
7239 | int ret; | |
7240 | ||
7241 | if (cnt >= sizeof(buf)) | |
7242 | return -EINVAL; | |
7243 | ||
4afe6495 | 7244 | if (copy_from_user(buf, ubuf, cnt)) |
e1e232ca SR |
7245 | return -EFAULT; |
7246 | ||
7247 | buf[cnt] = 0; | |
7248 | ||
7249 | clockstr = strstrip(buf); | |
7250 | ||
7251 | ret = tracing_set_clock(tr, clockstr); | |
7252 | if (ret) | |
7253 | return ret; | |
7254 | ||
5079f326 Z |
7255 | *fpos += cnt; |
7256 | ||
7257 | return cnt; | |
7258 | } | |
7259 | ||
13f16d20 LZ |
7260 | static int tracing_clock_open(struct inode *inode, struct file *file) |
7261 | { | |
7b85af63 SRRH |
7262 | struct trace_array *tr = inode->i_private; |
7263 | int ret; | |
7264 | ||
8530dec6 SRV |
7265 | ret = tracing_check_open_get_tr(tr); |
7266 | if (ret) | |
7267 | return ret; | |
7b85af63 SRRH |
7268 | |
7269 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
7270 | if (ret < 0) | |
7271 | trace_array_put(tr); | |
7272 | ||
7273 | return ret; | |
13f16d20 LZ |
7274 | } |
7275 | ||
2c1ea60b TZ |
7276 | static int tracing_time_stamp_mode_show(struct seq_file *m, void *v) |
7277 | { | |
7278 | struct trace_array *tr = m->private; | |
7279 | ||
7280 | mutex_lock(&trace_types_lock); | |
7281 | ||
1c5eb448 | 7282 | if (ring_buffer_time_stamp_abs(tr->array_buffer.buffer)) |
2c1ea60b TZ |
7283 | seq_puts(m, "delta [absolute]\n"); |
7284 | else | |
7285 | seq_puts(m, "[delta] absolute\n"); | |
7286 | ||
7287 | mutex_unlock(&trace_types_lock); | |
7288 | ||
7289 | return 0; | |
7290 | } | |
7291 | ||
7292 | static int tracing_time_stamp_mode_open(struct inode *inode, struct file *file) | |
7293 | { | |
7294 | struct trace_array *tr = inode->i_private; | |
7295 | int ret; | |
7296 | ||
8530dec6 SRV |
7297 | ret = tracing_check_open_get_tr(tr); |
7298 | if (ret) | |
7299 | return ret; | |
2c1ea60b TZ |
7300 | |
7301 | ret = single_open(file, tracing_time_stamp_mode_show, inode->i_private); | |
7302 | if (ret < 0) | |
7303 | trace_array_put(tr); | |
7304 | ||
7305 | return ret; | |
7306 | } | |
7307 | ||
d8279bfc SRV |
7308 | u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe) |
7309 | { | |
7310 | if (rbe == this_cpu_read(trace_buffered_event)) | |
f3ef7202 | 7311 | return ring_buffer_time_stamp(buffer); |
d8279bfc SRV |
7312 | |
7313 | return ring_buffer_event_time_stamp(buffer, rbe); | |
7314 | } | |
7315 | ||
b94bc80d SRV |
7316 | /* |
7317 | * Set or disable using the per CPU trace_buffer_event when possible. | |
7318 | */ | |
7319 | int tracing_set_filter_buffering(struct trace_array *tr, bool set) | |
00b41452 TZ |
7320 | { |
7321 | int ret = 0; | |
7322 | ||
7323 | mutex_lock(&trace_types_lock); | |
7324 | ||
b94bc80d | 7325 | if (set && tr->no_filter_buffering_ref++) |
00b41452 TZ |
7326 | goto out; |
7327 | ||
b94bc80d SRV |
7328 | if (!set) { |
7329 | if (WARN_ON_ONCE(!tr->no_filter_buffering_ref)) { | |
00b41452 TZ |
7330 | ret = -EINVAL; |
7331 | goto out; | |
7332 | } | |
7333 | ||
b94bc80d | 7334 | --tr->no_filter_buffering_ref; |
00b41452 | 7335 | } |
00b41452 TZ |
7336 | out: |
7337 | mutex_unlock(&trace_types_lock); | |
7338 | ||
7339 | return ret; | |
7340 | } | |
7341 | ||
6de58e62 SRRH |
7342 | struct ftrace_buffer_info { |
7343 | struct trace_iterator iter; | |
7344 | void *spare; | |
73a757e6 | 7345 | unsigned int spare_cpu; |
6de58e62 SRRH |
7346 | unsigned int read; |
7347 | }; | |
7348 | ||
debdd57f HT |
7349 | #ifdef CONFIG_TRACER_SNAPSHOT |
7350 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
7351 | { | |
6484c71c | 7352 | struct trace_array *tr = inode->i_private; |
debdd57f | 7353 | struct trace_iterator *iter; |
2b6080f2 | 7354 | struct seq_file *m; |
8530dec6 | 7355 | int ret; |
debdd57f | 7356 | |
8530dec6 SRV |
7357 | ret = tracing_check_open_get_tr(tr); |
7358 | if (ret) | |
7359 | return ret; | |
ff451961 | 7360 | |
debdd57f | 7361 | if (file->f_mode & FMODE_READ) { |
6484c71c | 7362 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
7363 | if (IS_ERR(iter)) |
7364 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
7365 | } else { |
7366 | /* Writes still need the seq_file to hold the private data */ | |
f77d09a3 | 7367 | ret = -ENOMEM; |
2b6080f2 SR |
7368 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
7369 | if (!m) | |
f77d09a3 | 7370 | goto out; |
2b6080f2 SR |
7371 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
7372 | if (!iter) { | |
7373 | kfree(m); | |
f77d09a3 | 7374 | goto out; |
2b6080f2 | 7375 | } |
f77d09a3 AL |
7376 | ret = 0; |
7377 | ||
ff451961 | 7378 | iter->tr = tr; |
1c5eb448 | 7379 | iter->array_buffer = &tr->max_buffer; |
6484c71c | 7380 | iter->cpu_file = tracing_get_cpu(inode); |
2b6080f2 SR |
7381 | m->private = iter; |
7382 | file->private_data = m; | |
debdd57f | 7383 | } |
f77d09a3 | 7384 | out: |
ff451961 SRRH |
7385 | if (ret < 0) |
7386 | trace_array_put(tr); | |
7387 | ||
debdd57f HT |
7388 | return ret; |
7389 | } | |
7390 | ||
7391 | static ssize_t | |
7392 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
7393 | loff_t *ppos) | |
7394 | { | |
2b6080f2 SR |
7395 | struct seq_file *m = filp->private_data; |
7396 | struct trace_iterator *iter = m->private; | |
7397 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
7398 | unsigned long val; |
7399 | int ret; | |
7400 | ||
7401 | ret = tracing_update_buffers(); | |
7402 | if (ret < 0) | |
7403 | return ret; | |
7404 | ||
7405 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
7406 | if (ret) | |
7407 | return ret; | |
7408 | ||
7409 | mutex_lock(&trace_types_lock); | |
7410 | ||
2b6080f2 | 7411 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
7412 | ret = -EBUSY; |
7413 | goto out; | |
7414 | } | |
7415 | ||
a35873a0 TZ |
7416 | arch_spin_lock(&tr->max_lock); |
7417 | if (tr->cond_snapshot) | |
7418 | ret = -EBUSY; | |
7419 | arch_spin_unlock(&tr->max_lock); | |
7420 | if (ret) | |
7421 | goto out; | |
7422 | ||
debdd57f HT |
7423 | switch (val) { |
7424 | case 0: | |
f1affcaa SRRH |
7425 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
7426 | ret = -EINVAL; | |
7427 | break; | |
debdd57f | 7428 | } |
3209cff4 SRRH |
7429 | if (tr->allocated_snapshot) |
7430 | free_snapshot(tr); | |
debdd57f HT |
7431 | break; |
7432 | case 1: | |
f1affcaa SRRH |
7433 | /* Only allow per-cpu swap if the ring buffer supports it */ |
7434 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
7435 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
7436 | ret = -EINVAL; | |
7437 | break; | |
7438 | } | |
7439 | #endif | |
46cc0b44 ET |
7440 | if (tr->allocated_snapshot) |
7441 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
1c5eb448 | 7442 | &tr->array_buffer, iter->cpu_file); |
46cc0b44 | 7443 | else |
2824f503 | 7444 | ret = tracing_alloc_snapshot_instance(tr); |
46cc0b44 ET |
7445 | if (ret < 0) |
7446 | break; | |
debdd57f HT |
7447 | local_irq_disable(); |
7448 | /* Now, we're going to swap */ | |
f1affcaa | 7449 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
a35873a0 | 7450 | update_max_tr(tr, current, smp_processor_id(), NULL); |
f1affcaa | 7451 | else |
ce9bae55 | 7452 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
7453 | local_irq_enable(); |
7454 | break; | |
7455 | default: | |
45ad21ca | 7456 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
7457 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
7458 | tracing_reset_online_cpus(&tr->max_buffer); | |
7459 | else | |
a47b53e9 | 7460 | tracing_reset_cpu(&tr->max_buffer, iter->cpu_file); |
f1affcaa | 7461 | } |
debdd57f HT |
7462 | break; |
7463 | } | |
7464 | ||
7465 | if (ret >= 0) { | |
7466 | *ppos += cnt; | |
7467 | ret = cnt; | |
7468 | } | |
7469 | out: | |
7470 | mutex_unlock(&trace_types_lock); | |
7471 | return ret; | |
7472 | } | |
2b6080f2 SR |
7473 | |
7474 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
7475 | { | |
7476 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
7477 | int ret; |
7478 | ||
7479 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
7480 | |
7481 | if (file->f_mode & FMODE_READ) | |
ff451961 | 7482 | return ret; |
2b6080f2 SR |
7483 | |
7484 | /* If write only, the seq_file is just a stub */ | |
7485 | if (m) | |
7486 | kfree(m->private); | |
7487 | kfree(m); | |
7488 | ||
7489 | return 0; | |
7490 | } | |
7491 | ||
6de58e62 SRRH |
7492 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
7493 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
7494 | size_t count, loff_t *ppos); | |
7495 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
7496 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
7497 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
7498 | ||
7499 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
7500 | { | |
7501 | struct ftrace_buffer_info *info; | |
7502 | int ret; | |
7503 | ||
17911ff3 | 7504 | /* The following checks for tracefs lockdown */ |
6de58e62 SRRH |
7505 | ret = tracing_buffers_open(inode, filp); |
7506 | if (ret < 0) | |
7507 | return ret; | |
7508 | ||
7509 | info = filp->private_data; | |
7510 | ||
7511 | if (info->iter.trace->use_max_tr) { | |
7512 | tracing_buffers_release(inode, filp); | |
7513 | return -EBUSY; | |
7514 | } | |
7515 | ||
7516 | info->iter.snapshot = true; | |
1c5eb448 | 7517 | info->iter.array_buffer = &info->iter.tr->max_buffer; |
6de58e62 SRRH |
7518 | |
7519 | return ret; | |
7520 | } | |
7521 | ||
debdd57f HT |
7522 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
7523 | ||
7524 | ||
6508fa76 SF |
7525 | static const struct file_operations tracing_thresh_fops = { |
7526 | .open = tracing_open_generic, | |
7527 | .read = tracing_thresh_read, | |
7528 | .write = tracing_thresh_write, | |
7529 | .llseek = generic_file_llseek, | |
7530 | }; | |
7531 | ||
f971cc9a | 7532 | #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) |
5e2336a0 | 7533 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
7534 | .open = tracing_open_generic, |
7535 | .read = tracing_max_lat_read, | |
7536 | .write = tracing_max_lat_write, | |
b444786f | 7537 | .llseek = generic_file_llseek, |
bc0c38d1 | 7538 | }; |
e428abbb | 7539 | #endif |
bc0c38d1 | 7540 | |
5e2336a0 | 7541 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
7542 | .open = tracing_open_generic, |
7543 | .read = tracing_set_trace_read, | |
7544 | .write = tracing_set_trace_write, | |
b444786f | 7545 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
7546 | }; |
7547 | ||
5e2336a0 | 7548 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 7549 | .open = tracing_open_pipe, |
2a2cc8f7 | 7550 | .poll = tracing_poll_pipe, |
4bf39a94 | 7551 | .read = tracing_read_pipe, |
3c56819b | 7552 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 7553 | .release = tracing_release_pipe, |
b444786f | 7554 | .llseek = no_llseek, |
b3806b43 SR |
7555 | }; |
7556 | ||
5e2336a0 | 7557 | static const struct file_operations tracing_entries_fops = { |
0bc392ee | 7558 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
7559 | .read = tracing_entries_read, |
7560 | .write = tracing_entries_write, | |
b444786f | 7561 | .llseek = generic_file_llseek, |
0bc392ee | 7562 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
7563 | }; |
7564 | ||
f81ab074 | 7565 | static const struct file_operations tracing_total_entries_fops = { |
7b85af63 | 7566 | .open = tracing_open_generic_tr, |
f81ab074 VN |
7567 | .read = tracing_total_entries_read, |
7568 | .llseek = generic_file_llseek, | |
7b85af63 | 7569 | .release = tracing_release_generic_tr, |
f81ab074 VN |
7570 | }; |
7571 | ||
4f271a2a | 7572 | static const struct file_operations tracing_free_buffer_fops = { |
7b85af63 | 7573 | .open = tracing_open_generic_tr, |
4f271a2a VN |
7574 | .write = tracing_free_buffer_write, |
7575 | .release = tracing_free_buffer_release, | |
7576 | }; | |
7577 | ||
5e2336a0 | 7578 | static const struct file_operations tracing_mark_fops = { |
7b85af63 | 7579 | .open = tracing_open_generic_tr, |
5bf9a1ee | 7580 | .write = tracing_mark_write, |
b444786f | 7581 | .llseek = generic_file_llseek, |
7b85af63 | 7582 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
7583 | }; |
7584 | ||
fa32e855 SR |
7585 | static const struct file_operations tracing_mark_raw_fops = { |
7586 | .open = tracing_open_generic_tr, | |
7587 | .write = tracing_mark_raw_write, | |
7588 | .llseek = generic_file_llseek, | |
7589 | .release = tracing_release_generic_tr, | |
7590 | }; | |
7591 | ||
5079f326 | 7592 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
7593 | .open = tracing_clock_open, |
7594 | .read = seq_read, | |
7595 | .llseek = seq_lseek, | |
7b85af63 | 7596 | .release = tracing_single_release_tr, |
5079f326 Z |
7597 | .write = tracing_clock_write, |
7598 | }; | |
7599 | ||
2c1ea60b TZ |
7600 | static const struct file_operations trace_time_stamp_mode_fops = { |
7601 | .open = tracing_time_stamp_mode_open, | |
7602 | .read = seq_read, | |
7603 | .llseek = seq_lseek, | |
7604 | .release = tracing_single_release_tr, | |
7605 | }; | |
7606 | ||
debdd57f HT |
7607 | #ifdef CONFIG_TRACER_SNAPSHOT |
7608 | static const struct file_operations snapshot_fops = { | |
7609 | .open = tracing_snapshot_open, | |
7610 | .read = seq_read, | |
7611 | .write = tracing_snapshot_write, | |
098c879e | 7612 | .llseek = tracing_lseek, |
2b6080f2 | 7613 | .release = tracing_snapshot_release, |
debdd57f | 7614 | }; |
debdd57f | 7615 | |
6de58e62 SRRH |
7616 | static const struct file_operations snapshot_raw_fops = { |
7617 | .open = snapshot_raw_open, | |
7618 | .read = tracing_buffers_read, | |
7619 | .release = tracing_buffers_release, | |
7620 | .splice_read = tracing_buffers_splice_read, | |
7621 | .llseek = no_llseek, | |
2cadf913 SR |
7622 | }; |
7623 | ||
6de58e62 SRRH |
7624 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
7625 | ||
bc87cf0a DBO |
7626 | /* |
7627 | * trace_min_max_write - Write a u64 value to a trace_min_max_param struct | |
7628 | * @filp: The active open file structure | |
7629 | * @ubuf: The userspace provided buffer to read value into | |
7630 | * @cnt: The maximum number of bytes to read | |
7631 | * @ppos: The current "file" position | |
7632 | * | |
7633 | * This function implements the write interface for a struct trace_min_max_param. | |
7634 | * The filp->private_data must point to a trace_min_max_param structure that | |
7635 | * defines where to write the value, the min and the max acceptable values, | |
7636 | * and a lock to protect the write. | |
7637 | */ | |
7638 | static ssize_t | |
7639 | trace_min_max_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) | |
7640 | { | |
7641 | struct trace_min_max_param *param = filp->private_data; | |
7642 | u64 val; | |
7643 | int err; | |
7644 | ||
7645 | if (!param) | |
7646 | return -EFAULT; | |
7647 | ||
7648 | err = kstrtoull_from_user(ubuf, cnt, 10, &val); | |
7649 | if (err) | |
7650 | return err; | |
7651 | ||
7652 | if (param->lock) | |
7653 | mutex_lock(param->lock); | |
7654 | ||
7655 | if (param->min && val < *param->min) | |
7656 | err = -EINVAL; | |
7657 | ||
7658 | if (param->max && val > *param->max) | |
7659 | err = -EINVAL; | |
7660 | ||
7661 | if (!err) | |
7662 | *param->val = val; | |
7663 | ||
7664 | if (param->lock) | |
7665 | mutex_unlock(param->lock); | |
7666 | ||
7667 | if (err) | |
7668 | return err; | |
7669 | ||
7670 | return cnt; | |
7671 | } | |
7672 | ||
7673 | /* | |
7674 | * trace_min_max_read - Read a u64 value from a trace_min_max_param struct | |
7675 | * @filp: The active open file structure | |
7676 | * @ubuf: The userspace provided buffer to read value into | |
7677 | * @cnt: The maximum number of bytes to read | |
7678 | * @ppos: The current "file" position | |
7679 | * | |
7680 | * This function implements the read interface for a struct trace_min_max_param. | |
7681 | * The filp->private_data must point to a trace_min_max_param struct with valid | |
7682 | * data. | |
7683 | */ | |
7684 | static ssize_t | |
7685 | trace_min_max_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) | |
7686 | { | |
7687 | struct trace_min_max_param *param = filp->private_data; | |
7688 | char buf[U64_STR_SIZE]; | |
7689 | int len; | |
7690 | u64 val; | |
7691 | ||
7692 | if (!param) | |
7693 | return -EFAULT; | |
7694 | ||
7695 | val = *param->val; | |
7696 | ||
7697 | if (cnt > sizeof(buf)) | |
7698 | cnt = sizeof(buf); | |
7699 | ||
7700 | len = snprintf(buf, sizeof(buf), "%llu\n", val); | |
7701 | ||
7702 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, len); | |
7703 | } | |
7704 | ||
7705 | const struct file_operations trace_min_max_fops = { | |
7706 | .open = tracing_open_generic, | |
7707 | .read = trace_min_max_read, | |
7708 | .write = trace_min_max_write, | |
7709 | }; | |
7710 | ||
8a062902 TZ |
7711 | #define TRACING_LOG_ERRS_MAX 8 |
7712 | #define TRACING_LOG_LOC_MAX 128 | |
7713 | ||
7714 | #define CMD_PREFIX " Command: " | |
7715 | ||
7716 | struct err_info { | |
7717 | const char **errs; /* ptr to loc-specific array of err strings */ | |
7718 | u8 type; /* index into errs -> specific err string */ | |
7719 | u8 pos; /* MAX_FILTER_STR_VAL = 256 */ | |
7720 | u64 ts; | |
7721 | }; | |
7722 | ||
7723 | struct tracing_log_err { | |
7724 | struct list_head list; | |
7725 | struct err_info info; | |
7726 | char loc[TRACING_LOG_LOC_MAX]; /* err location */ | |
7727 | char cmd[MAX_FILTER_STR_VAL]; /* what caused err */ | |
7728 | }; | |
7729 | ||
8a062902 TZ |
7730 | static DEFINE_MUTEX(tracing_err_log_lock); |
7731 | ||
ff585c5b | 7732 | static struct tracing_log_err *get_tracing_log_err(struct trace_array *tr) |
8a062902 TZ |
7733 | { |
7734 | struct tracing_log_err *err; | |
7735 | ||
2f754e77 | 7736 | if (tr->n_err_log_entries < TRACING_LOG_ERRS_MAX) { |
8a062902 TZ |
7737 | err = kzalloc(sizeof(*err), GFP_KERNEL); |
7738 | if (!err) | |
7739 | err = ERR_PTR(-ENOMEM); | |
2f754e77 | 7740 | tr->n_err_log_entries++; |
8a062902 TZ |
7741 | |
7742 | return err; | |
7743 | } | |
7744 | ||
2f754e77 | 7745 | err = list_first_entry(&tr->err_log, struct tracing_log_err, list); |
8a062902 TZ |
7746 | list_del(&err->list); |
7747 | ||
7748 | return err; | |
7749 | } | |
7750 | ||
7751 | /** | |
7752 | * err_pos - find the position of a string within a command for error careting | |
7753 | * @cmd: The tracing command that caused the error | |
7754 | * @str: The string to position the caret at within @cmd | |
7755 | * | |
f2cc020d | 7756 | * Finds the position of the first occurrence of @str within @cmd. The |
8a062902 TZ |
7757 | * return value can be passed to tracing_log_err() for caret placement |
7758 | * within @cmd. | |
7759 | * | |
f2cc020d | 7760 | * Returns the index within @cmd of the first occurrence of @str or 0 |
8a062902 TZ |
7761 | * if @str was not found. |
7762 | */ | |
7763 | unsigned int err_pos(char *cmd, const char *str) | |
7764 | { | |
7765 | char *found; | |
7766 | ||
7767 | if (WARN_ON(!strlen(cmd))) | |
7768 | return 0; | |
7769 | ||
7770 | found = strstr(cmd, str); | |
7771 | if (found) | |
7772 | return found - cmd; | |
7773 | ||
7774 | return 0; | |
7775 | } | |
7776 | ||
7777 | /** | |
7778 | * tracing_log_err - write an error to the tracing error log | |
2f754e77 | 7779 | * @tr: The associated trace array for the error (NULL for top level array) |
8a062902 TZ |
7780 | * @loc: A string describing where the error occurred |
7781 | * @cmd: The tracing command that caused the error | |
7782 | * @errs: The array of loc-specific static error strings | |
7783 | * @type: The index into errs[], which produces the specific static err string | |
7784 | * @pos: The position the caret should be placed in the cmd | |
7785 | * | |
7786 | * Writes an error into tracing/error_log of the form: | |
7787 | * | |
7788 | * <loc>: error: <text> | |
7789 | * Command: <cmd> | |
7790 | * ^ | |
7791 | * | |
7792 | * tracing/error_log is a small log file containing the last | |
7793 | * TRACING_LOG_ERRS_MAX errors (8). Memory for errors isn't allocated | |
7794 | * unless there has been a tracing error, and the error log can be | |
7795 | * cleared and have its memory freed by writing the empty string in | |
7796 | * truncation mode to it i.e. echo > tracing/error_log. | |
7797 | * | |
7798 | * NOTE: the @errs array along with the @type param are used to | |
7799 | * produce a static error string - this string is not copied and saved | |
7800 | * when the error is logged - only a pointer to it is saved. See | |
7801 | * existing callers for examples of how static strings are typically | |
7802 | * defined for use with tracing_log_err(). | |
7803 | */ | |
2f754e77 SRV |
7804 | void tracing_log_err(struct trace_array *tr, |
7805 | const char *loc, const char *cmd, | |
8a062902 TZ |
7806 | const char **errs, u8 type, u8 pos) |
7807 | { | |
7808 | struct tracing_log_err *err; | |
7809 | ||
2f754e77 SRV |
7810 | if (!tr) |
7811 | tr = &global_trace; | |
7812 | ||
8a062902 | 7813 | mutex_lock(&tracing_err_log_lock); |
2f754e77 | 7814 | err = get_tracing_log_err(tr); |
8a062902 TZ |
7815 | if (PTR_ERR(err) == -ENOMEM) { |
7816 | mutex_unlock(&tracing_err_log_lock); | |
7817 | return; | |
7818 | } | |
7819 | ||
7820 | snprintf(err->loc, TRACING_LOG_LOC_MAX, "%s: error: ", loc); | |
7821 | snprintf(err->cmd, MAX_FILTER_STR_VAL,"\n" CMD_PREFIX "%s\n", cmd); | |
7822 | ||
7823 | err->info.errs = errs; | |
7824 | err->info.type = type; | |
7825 | err->info.pos = pos; | |
7826 | err->info.ts = local_clock(); | |
7827 | ||
2f754e77 | 7828 | list_add_tail(&err->list, &tr->err_log); |
8a062902 TZ |
7829 | mutex_unlock(&tracing_err_log_lock); |
7830 | } | |
7831 | ||
2f754e77 | 7832 | static void clear_tracing_err_log(struct trace_array *tr) |
8a062902 TZ |
7833 | { |
7834 | struct tracing_log_err *err, *next; | |
7835 | ||
7836 | mutex_lock(&tracing_err_log_lock); | |
2f754e77 | 7837 | list_for_each_entry_safe(err, next, &tr->err_log, list) { |
8a062902 TZ |
7838 | list_del(&err->list); |
7839 | kfree(err); | |
7840 | } | |
7841 | ||
2f754e77 | 7842 | tr->n_err_log_entries = 0; |
8a062902 TZ |
7843 | mutex_unlock(&tracing_err_log_lock); |
7844 | } | |
7845 | ||
7846 | static void *tracing_err_log_seq_start(struct seq_file *m, loff_t *pos) | |
7847 | { | |
2f754e77 SRV |
7848 | struct trace_array *tr = m->private; |
7849 | ||
8a062902 TZ |
7850 | mutex_lock(&tracing_err_log_lock); |
7851 | ||
2f754e77 | 7852 | return seq_list_start(&tr->err_log, *pos); |
8a062902 TZ |
7853 | } |
7854 | ||
7855 | static void *tracing_err_log_seq_next(struct seq_file *m, void *v, loff_t *pos) | |
7856 | { | |
2f754e77 SRV |
7857 | struct trace_array *tr = m->private; |
7858 | ||
7859 | return seq_list_next(v, &tr->err_log, pos); | |
8a062902 TZ |
7860 | } |
7861 | ||
7862 | static void tracing_err_log_seq_stop(struct seq_file *m, void *v) | |
7863 | { | |
7864 | mutex_unlock(&tracing_err_log_lock); | |
7865 | } | |
7866 | ||
7867 | static void tracing_err_log_show_pos(struct seq_file *m, u8 pos) | |
7868 | { | |
7869 | u8 i; | |
7870 | ||
7871 | for (i = 0; i < sizeof(CMD_PREFIX) - 1; i++) | |
7872 | seq_putc(m, ' '); | |
7873 | for (i = 0; i < pos; i++) | |
7874 | seq_putc(m, ' '); | |
7875 | seq_puts(m, "^\n"); | |
7876 | } | |
7877 | ||
7878 | static int tracing_err_log_seq_show(struct seq_file *m, void *v) | |
7879 | { | |
7880 | struct tracing_log_err *err = v; | |
7881 | ||
7882 | if (err) { | |
7883 | const char *err_text = err->info.errs[err->info.type]; | |
7884 | u64 sec = err->info.ts; | |
7885 | u32 nsec; | |
7886 | ||
7887 | nsec = do_div(sec, NSEC_PER_SEC); | |
7888 | seq_printf(m, "[%5llu.%06u] %s%s", sec, nsec / 1000, | |
7889 | err->loc, err_text); | |
7890 | seq_printf(m, "%s", err->cmd); | |
7891 | tracing_err_log_show_pos(m, err->info.pos); | |
7892 | } | |
7893 | ||
7894 | return 0; | |
7895 | } | |
7896 | ||
7897 | static const struct seq_operations tracing_err_log_seq_ops = { | |
7898 | .start = tracing_err_log_seq_start, | |
7899 | .next = tracing_err_log_seq_next, | |
7900 | .stop = tracing_err_log_seq_stop, | |
7901 | .show = tracing_err_log_seq_show | |
7902 | }; | |
7903 | ||
7904 | static int tracing_err_log_open(struct inode *inode, struct file *file) | |
7905 | { | |
2f754e77 | 7906 | struct trace_array *tr = inode->i_private; |
8a062902 TZ |
7907 | int ret = 0; |
7908 | ||
8530dec6 SRV |
7909 | ret = tracing_check_open_get_tr(tr); |
7910 | if (ret) | |
7911 | return ret; | |
2f754e77 | 7912 | |
8a062902 TZ |
7913 | /* If this file was opened for write, then erase contents */ |
7914 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) | |
2f754e77 | 7915 | clear_tracing_err_log(tr); |
8a062902 | 7916 | |
2f754e77 | 7917 | if (file->f_mode & FMODE_READ) { |
8a062902 | 7918 | ret = seq_open(file, &tracing_err_log_seq_ops); |
2f754e77 SRV |
7919 | if (!ret) { |
7920 | struct seq_file *m = file->private_data; | |
7921 | m->private = tr; | |
7922 | } else { | |
7923 | trace_array_put(tr); | |
7924 | } | |
7925 | } | |
8a062902 TZ |
7926 | return ret; |
7927 | } | |
7928 | ||
7929 | static ssize_t tracing_err_log_write(struct file *file, | |
7930 | const char __user *buffer, | |
7931 | size_t count, loff_t *ppos) | |
7932 | { | |
7933 | return count; | |
7934 | } | |
7935 | ||
d122ed62 TM |
7936 | static int tracing_err_log_release(struct inode *inode, struct file *file) |
7937 | { | |
7938 | struct trace_array *tr = inode->i_private; | |
7939 | ||
7940 | trace_array_put(tr); | |
7941 | ||
7942 | if (file->f_mode & FMODE_READ) | |
7943 | seq_release(inode, file); | |
7944 | ||
7945 | return 0; | |
7946 | } | |
7947 | ||
8a062902 TZ |
7948 | static const struct file_operations tracing_err_log_fops = { |
7949 | .open = tracing_err_log_open, | |
7950 | .write = tracing_err_log_write, | |
7951 | .read = seq_read, | |
7952 | .llseek = seq_lseek, | |
d122ed62 | 7953 | .release = tracing_err_log_release, |
8a062902 TZ |
7954 | }; |
7955 | ||
2cadf913 SR |
7956 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
7957 | { | |
46ef2be0 | 7958 | struct trace_array *tr = inode->i_private; |
2cadf913 | 7959 | struct ftrace_buffer_info *info; |
7b85af63 | 7960 | int ret; |
2cadf913 | 7961 | |
8530dec6 SRV |
7962 | ret = tracing_check_open_get_tr(tr); |
7963 | if (ret) | |
7964 | return ret; | |
7b85af63 | 7965 | |
0f69dae4 | 7966 | info = kvzalloc(sizeof(*info), GFP_KERNEL); |
7b85af63 SRRH |
7967 | if (!info) { |
7968 | trace_array_put(tr); | |
2cadf913 | 7969 | return -ENOMEM; |
7b85af63 | 7970 | } |
2cadf913 | 7971 | |
a695cb58 SRRH |
7972 | mutex_lock(&trace_types_lock); |
7973 | ||
cc60cdc9 | 7974 | info->iter.tr = tr; |
46ef2be0 | 7975 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 7976 | info->iter.trace = tr->current_trace; |
1c5eb448 | 7977 | info->iter.array_buffer = &tr->array_buffer; |
cc60cdc9 | 7978 | info->spare = NULL; |
2cadf913 | 7979 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 7980 | info->read = (unsigned int)-1; |
2cadf913 SR |
7981 | |
7982 | filp->private_data = info; | |
7983 | ||
7ef282e0 | 7984 | tr->trace_ref++; |
cf6ab6d9 | 7985 | |
a695cb58 SRRH |
7986 | mutex_unlock(&trace_types_lock); |
7987 | ||
7b85af63 SRRH |
7988 | ret = nonseekable_open(inode, filp); |
7989 | if (ret < 0) | |
7990 | trace_array_put(tr); | |
7991 | ||
7992 | return ret; | |
2cadf913 SR |
7993 | } |
7994 | ||
9dd95748 | 7995 | static __poll_t |
cc60cdc9 SR |
7996 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) |
7997 | { | |
7998 | struct ftrace_buffer_info *info = filp->private_data; | |
7999 | struct trace_iterator *iter = &info->iter; | |
8000 | ||
8001 | return trace_poll(iter, filp, poll_table); | |
8002 | } | |
8003 | ||
2cadf913 SR |
8004 | static ssize_t |
8005 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
8006 | size_t count, loff_t *ppos) | |
8007 | { | |
8008 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 8009 | struct trace_iterator *iter = &info->iter; |
a7e52ad7 | 8010 | ssize_t ret = 0; |
6de58e62 | 8011 | ssize_t size; |
2cadf913 | 8012 | |
2dc5d12b SR |
8013 | if (!count) |
8014 | return 0; | |
8015 | ||
6de58e62 | 8016 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
8017 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
8018 | return -EBUSY; | |
6de58e62 SRRH |
8019 | #endif |
8020 | ||
73a757e6 | 8021 | if (!info->spare) { |
1c5eb448 | 8022 | info->spare = ring_buffer_alloc_read_page(iter->array_buffer->buffer, |
12883efb | 8023 | iter->cpu_file); |
a7e52ad7 SRV |
8024 | if (IS_ERR(info->spare)) { |
8025 | ret = PTR_ERR(info->spare); | |
8026 | info->spare = NULL; | |
8027 | } else { | |
8028 | info->spare_cpu = iter->cpu_file; | |
8029 | } | |
73a757e6 | 8030 | } |
ddd538f3 | 8031 | if (!info->spare) |
a7e52ad7 | 8032 | return ret; |
ddd538f3 | 8033 | |
2cadf913 SR |
8034 | /* Do we have previous read data to read? */ |
8035 | if (info->read < PAGE_SIZE) | |
8036 | goto read; | |
8037 | ||
b627344f | 8038 | again: |
cc60cdc9 | 8039 | trace_access_lock(iter->cpu_file); |
1c5eb448 | 8040 | ret = ring_buffer_read_page(iter->array_buffer->buffer, |
2cadf913 SR |
8041 | &info->spare, |
8042 | count, | |
cc60cdc9 SR |
8043 | iter->cpu_file, 0); |
8044 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 8045 | |
b627344f SR |
8046 | if (ret < 0) { |
8047 | if (trace_empty(iter)) { | |
d716ff71 SRRH |
8048 | if ((filp->f_flags & O_NONBLOCK)) |
8049 | return -EAGAIN; | |
8050 | ||
2c2b0a78 | 8051 | ret = wait_on_pipe(iter, 0); |
d716ff71 SRRH |
8052 | if (ret) |
8053 | return ret; | |
8054 | ||
b627344f SR |
8055 | goto again; |
8056 | } | |
d716ff71 | 8057 | return 0; |
b627344f | 8058 | } |
436fc280 | 8059 | |
436fc280 | 8060 | info->read = 0; |
b627344f | 8061 | read: |
2cadf913 SR |
8062 | size = PAGE_SIZE - info->read; |
8063 | if (size > count) | |
8064 | size = count; | |
8065 | ||
8066 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
d716ff71 SRRH |
8067 | if (ret == size) |
8068 | return -EFAULT; | |
8069 | ||
2dc5d12b SR |
8070 | size -= ret; |
8071 | ||
2cadf913 SR |
8072 | *ppos += size; |
8073 | info->read += size; | |
8074 | ||
8075 | return size; | |
8076 | } | |
8077 | ||
8078 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
8079 | { | |
8080 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 8081 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 8082 | |
a695cb58 SRRH |
8083 | mutex_lock(&trace_types_lock); |
8084 | ||
7ef282e0 | 8085 | iter->tr->trace_ref--; |
cf6ab6d9 | 8086 | |
ff451961 | 8087 | __trace_array_put(iter->tr); |
2cadf913 | 8088 | |
ddd538f3 | 8089 | if (info->spare) |
1c5eb448 | 8090 | ring_buffer_free_read_page(iter->array_buffer->buffer, |
73a757e6 | 8091 | info->spare_cpu, info->spare); |
0f69dae4 | 8092 | kvfree(info); |
2cadf913 | 8093 | |
a695cb58 SRRH |
8094 | mutex_unlock(&trace_types_lock); |
8095 | ||
2cadf913 SR |
8096 | return 0; |
8097 | } | |
8098 | ||
8099 | struct buffer_ref { | |
13292494 | 8100 | struct trace_buffer *buffer; |
2cadf913 | 8101 | void *page; |
73a757e6 | 8102 | int cpu; |
b9872226 | 8103 | refcount_t refcount; |
2cadf913 SR |
8104 | }; |
8105 | ||
b9872226 JH |
8106 | static void buffer_ref_release(struct buffer_ref *ref) |
8107 | { | |
8108 | if (!refcount_dec_and_test(&ref->refcount)) | |
8109 | return; | |
8110 | ring_buffer_free_read_page(ref->buffer, ref->cpu, ref->page); | |
8111 | kfree(ref); | |
8112 | } | |
8113 | ||
2cadf913 SR |
8114 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, |
8115 | struct pipe_buffer *buf) | |
8116 | { | |
8117 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
8118 | ||
b9872226 | 8119 | buffer_ref_release(ref); |
2cadf913 SR |
8120 | buf->private = 0; |
8121 | } | |
8122 | ||
15fab63e | 8123 | static bool buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
2cadf913 SR |
8124 | struct pipe_buffer *buf) |
8125 | { | |
8126 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
8127 | ||
e9e1a2e7 | 8128 | if (refcount_read(&ref->refcount) > INT_MAX/2) |
15fab63e MW |
8129 | return false; |
8130 | ||
b9872226 | 8131 | refcount_inc(&ref->refcount); |
15fab63e | 8132 | return true; |
2cadf913 SR |
8133 | } |
8134 | ||
8135 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 8136 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 | 8137 | .release = buffer_pipe_buf_release, |
2cadf913 SR |
8138 | .get = buffer_pipe_buf_get, |
8139 | }; | |
8140 | ||
8141 | /* | |
8142 | * Callback from splice_to_pipe(), if we need to release some pages | |
8143 | * at the end of the spd in case we error'ed out in filling the pipe. | |
8144 | */ | |
8145 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
8146 | { | |
8147 | struct buffer_ref *ref = | |
8148 | (struct buffer_ref *)spd->partial[i].private; | |
8149 | ||
b9872226 | 8150 | buffer_ref_release(ref); |
2cadf913 SR |
8151 | spd->partial[i].private = 0; |
8152 | } | |
8153 | ||
8154 | static ssize_t | |
8155 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
8156 | struct pipe_inode_info *pipe, size_t len, | |
8157 | unsigned int flags) | |
8158 | { | |
8159 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 8160 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
8161 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
8162 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 8163 | struct splice_pipe_desc spd = { |
35f3d14d JA |
8164 | .pages = pages_def, |
8165 | .partial = partial_def, | |
047fe360 | 8166 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
8167 | .ops = &buffer_pipe_buf_ops, |
8168 | .spd_release = buffer_spd_release, | |
8169 | }; | |
8170 | struct buffer_ref *ref; | |
6b7e633f | 8171 | int entries, i; |
07906da7 | 8172 | ssize_t ret = 0; |
2cadf913 | 8173 | |
6de58e62 | 8174 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
8175 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
8176 | return -EBUSY; | |
6de58e62 SRRH |
8177 | #endif |
8178 | ||
d716ff71 SRRH |
8179 | if (*ppos & (PAGE_SIZE - 1)) |
8180 | return -EINVAL; | |
93cfb3c9 LJ |
8181 | |
8182 | if (len & (PAGE_SIZE - 1)) { | |
d716ff71 SRRH |
8183 | if (len < PAGE_SIZE) |
8184 | return -EINVAL; | |
93cfb3c9 LJ |
8185 | len &= PAGE_MASK; |
8186 | } | |
8187 | ||
1ae2293d AV |
8188 | if (splice_grow_spd(pipe, &spd)) |
8189 | return -ENOMEM; | |
8190 | ||
cc60cdc9 SR |
8191 | again: |
8192 | trace_access_lock(iter->cpu_file); | |
1c5eb448 | 8193 | entries = ring_buffer_entries_cpu(iter->array_buffer->buffer, iter->cpu_file); |
93459c6c | 8194 | |
a786c06d | 8195 | for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
8196 | struct page *page; |
8197 | int r; | |
8198 | ||
8199 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
07906da7 RV |
8200 | if (!ref) { |
8201 | ret = -ENOMEM; | |
2cadf913 | 8202 | break; |
07906da7 | 8203 | } |
2cadf913 | 8204 | |
b9872226 | 8205 | refcount_set(&ref->refcount, 1); |
1c5eb448 | 8206 | ref->buffer = iter->array_buffer->buffer; |
cc60cdc9 | 8207 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
a7e52ad7 SRV |
8208 | if (IS_ERR(ref->page)) { |
8209 | ret = PTR_ERR(ref->page); | |
8210 | ref->page = NULL; | |
2cadf913 SR |
8211 | kfree(ref); |
8212 | break; | |
8213 | } | |
73a757e6 | 8214 | ref->cpu = iter->cpu_file; |
2cadf913 SR |
8215 | |
8216 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 8217 | len, iter->cpu_file, 1); |
2cadf913 | 8218 | if (r < 0) { |
73a757e6 SRV |
8219 | ring_buffer_free_read_page(ref->buffer, ref->cpu, |
8220 | ref->page); | |
2cadf913 SR |
8221 | kfree(ref); |
8222 | break; | |
8223 | } | |
8224 | ||
2cadf913 SR |
8225 | page = virt_to_page(ref->page); |
8226 | ||
8227 | spd.pages[i] = page; | |
8228 | spd.partial[i].len = PAGE_SIZE; | |
8229 | spd.partial[i].offset = 0; | |
8230 | spd.partial[i].private = (unsigned long)ref; | |
8231 | spd.nr_pages++; | |
93cfb3c9 | 8232 | *ppos += PAGE_SIZE; |
93459c6c | 8233 | |
1c5eb448 | 8234 | entries = ring_buffer_entries_cpu(iter->array_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
8235 | } |
8236 | ||
cc60cdc9 | 8237 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
8238 | spd.nr_pages = i; |
8239 | ||
8240 | /* did we read anything? */ | |
8241 | if (!spd.nr_pages) { | |
07906da7 | 8242 | if (ret) |
1ae2293d | 8243 | goto out; |
d716ff71 | 8244 | |
1ae2293d | 8245 | ret = -EAGAIN; |
d716ff71 | 8246 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) |
1ae2293d | 8247 | goto out; |
07906da7 | 8248 | |
03329f99 | 8249 | ret = wait_on_pipe(iter, iter->tr->buffer_percent); |
8b8b3683 | 8250 | if (ret) |
1ae2293d | 8251 | goto out; |
e30f53aa | 8252 | |
cc60cdc9 | 8253 | goto again; |
2cadf913 SR |
8254 | } |
8255 | ||
8256 | ret = splice_to_pipe(pipe, &spd); | |
1ae2293d | 8257 | out: |
047fe360 | 8258 | splice_shrink_spd(&spd); |
6de58e62 | 8259 | |
2cadf913 SR |
8260 | return ret; |
8261 | } | |
8262 | ||
8263 | static const struct file_operations tracing_buffers_fops = { | |
8264 | .open = tracing_buffers_open, | |
8265 | .read = tracing_buffers_read, | |
cc60cdc9 | 8266 | .poll = tracing_buffers_poll, |
2cadf913 SR |
8267 | .release = tracing_buffers_release, |
8268 | .splice_read = tracing_buffers_splice_read, | |
8269 | .llseek = no_llseek, | |
8270 | }; | |
8271 | ||
c8d77183 SR |
8272 | static ssize_t |
8273 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
8274 | size_t count, loff_t *ppos) | |
8275 | { | |
4d3435b8 ON |
8276 | struct inode *inode = file_inode(filp); |
8277 | struct trace_array *tr = inode->i_private; | |
1c5eb448 | 8278 | struct array_buffer *trace_buf = &tr->array_buffer; |
4d3435b8 | 8279 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
8280 | struct trace_seq *s; |
8281 | unsigned long cnt; | |
c64e148a VN |
8282 | unsigned long long t; |
8283 | unsigned long usec_rem; | |
c8d77183 | 8284 | |
e4f2d10f | 8285 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 8286 | if (!s) |
a646365c | 8287 | return -ENOMEM; |
c8d77183 SR |
8288 | |
8289 | trace_seq_init(s); | |
8290 | ||
12883efb | 8291 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
8292 | trace_seq_printf(s, "entries: %ld\n", cnt); |
8293 | ||
12883efb | 8294 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
8295 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
8296 | ||
12883efb | 8297 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
8298 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
8299 | ||
12883efb | 8300 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
8301 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
8302 | ||
58e8eedf | 8303 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 8304 | /* local or global for trace_clock */ |
12883efb | 8305 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
8306 | usec_rem = do_div(t, USEC_PER_SEC); |
8307 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
8308 | t, usec_rem); | |
8309 | ||
f3ef7202 | 8310 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer)); |
11043d8b YY |
8311 | usec_rem = do_div(t, USEC_PER_SEC); |
8312 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
8313 | } else { | |
8314 | /* counter or tsc mode for trace_clock */ | |
8315 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 8316 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 8317 | |
11043d8b | 8318 | trace_seq_printf(s, "now ts: %llu\n", |
f3ef7202 | 8319 | ring_buffer_time_stamp(trace_buf->buffer)); |
11043d8b | 8320 | } |
c64e148a | 8321 | |
12883efb | 8322 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
8323 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
8324 | ||
12883efb | 8325 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
8326 | trace_seq_printf(s, "read events: %ld\n", cnt); |
8327 | ||
5ac48378 SRRH |
8328 | count = simple_read_from_buffer(ubuf, count, ppos, |
8329 | s->buffer, trace_seq_used(s)); | |
c8d77183 SR |
8330 | |
8331 | kfree(s); | |
8332 | ||
8333 | return count; | |
8334 | } | |
8335 | ||
8336 | static const struct file_operations tracing_stats_fops = { | |
4d3435b8 | 8337 | .open = tracing_open_generic_tr, |
c8d77183 | 8338 | .read = tracing_stats_read, |
b444786f | 8339 | .llseek = generic_file_llseek, |
4d3435b8 | 8340 | .release = tracing_release_generic_tr, |
c8d77183 SR |
8341 | }; |
8342 | ||
bc0c38d1 SR |
8343 | #ifdef CONFIG_DYNAMIC_FTRACE |
8344 | ||
8345 | static ssize_t | |
b807c3d0 | 8346 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
8347 | size_t cnt, loff_t *ppos) |
8348 | { | |
da537f0a SRV |
8349 | ssize_t ret; |
8350 | char *buf; | |
bc0c38d1 SR |
8351 | int r; |
8352 | ||
da537f0a SRV |
8353 | /* 256 should be plenty to hold the amount needed */ |
8354 | buf = kmalloc(256, GFP_KERNEL); | |
8355 | if (!buf) | |
8356 | return -ENOMEM; | |
b807c3d0 | 8357 | |
da537f0a SRV |
8358 | r = scnprintf(buf, 256, "%ld pages:%ld groups: %ld\n", |
8359 | ftrace_update_tot_cnt, | |
8360 | ftrace_number_of_pages, | |
8361 | ftrace_number_of_groups); | |
8362 | ||
8363 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
8364 | kfree(buf); | |
8365 | return ret; | |
bc0c38d1 SR |
8366 | } |
8367 | ||
5e2336a0 | 8368 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 8369 | .open = tracing_open_generic, |
b807c3d0 | 8370 | .read = tracing_read_dyn_info, |
b444786f | 8371 | .llseek = generic_file_llseek, |
bc0c38d1 | 8372 | }; |
77fd5c15 | 8373 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 8374 | |
77fd5c15 SRRH |
8375 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
8376 | static void | |
bca6c8d0 | 8377 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, |
b5f081b5 | 8378 | struct trace_array *tr, struct ftrace_probe_ops *ops, |
6e444319 | 8379 | void *data) |
77fd5c15 | 8380 | { |
cab50379 | 8381 | tracing_snapshot_instance(tr); |
77fd5c15 | 8382 | } |
bc0c38d1 | 8383 | |
77fd5c15 | 8384 | static void |
bca6c8d0 | 8385 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, |
b5f081b5 | 8386 | struct trace_array *tr, struct ftrace_probe_ops *ops, |
6e444319 | 8387 | void *data) |
bc0c38d1 | 8388 | { |
6e444319 | 8389 | struct ftrace_func_mapper *mapper = data; |
1a93f8bd | 8390 | long *count = NULL; |
77fd5c15 | 8391 | |
1a93f8bd SRV |
8392 | if (mapper) |
8393 | count = (long *)ftrace_func_mapper_find_ip(mapper, ip); | |
8394 | ||
8395 | if (count) { | |
8396 | ||
8397 | if (*count <= 0) | |
8398 | return; | |
bc0c38d1 | 8399 | |
77fd5c15 | 8400 | (*count)--; |
1a93f8bd | 8401 | } |
77fd5c15 | 8402 | |
cab50379 | 8403 | tracing_snapshot_instance(tr); |
77fd5c15 SRRH |
8404 | } |
8405 | ||
8406 | static int | |
8407 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
8408 | struct ftrace_probe_ops *ops, void *data) | |
8409 | { | |
6e444319 | 8410 | struct ftrace_func_mapper *mapper = data; |
1a93f8bd | 8411 | long *count = NULL; |
77fd5c15 SRRH |
8412 | |
8413 | seq_printf(m, "%ps:", (void *)ip); | |
8414 | ||
fa6f0cc7 | 8415 | seq_puts(m, "snapshot"); |
77fd5c15 | 8416 | |
1a93f8bd SRV |
8417 | if (mapper) |
8418 | count = (long *)ftrace_func_mapper_find_ip(mapper, ip); | |
8419 | ||
8420 | if (count) | |
8421 | seq_printf(m, ":count=%ld\n", *count); | |
77fd5c15 | 8422 | else |
1a93f8bd | 8423 | seq_puts(m, ":unlimited\n"); |
77fd5c15 SRRH |
8424 | |
8425 | return 0; | |
8426 | } | |
8427 | ||
1a93f8bd | 8428 | static int |
b5f081b5 | 8429 | ftrace_snapshot_init(struct ftrace_probe_ops *ops, struct trace_array *tr, |
6e444319 | 8430 | unsigned long ip, void *init_data, void **data) |
1a93f8bd | 8431 | { |
6e444319 SRV |
8432 | struct ftrace_func_mapper *mapper = *data; |
8433 | ||
8434 | if (!mapper) { | |
8435 | mapper = allocate_ftrace_func_mapper(); | |
8436 | if (!mapper) | |
8437 | return -ENOMEM; | |
8438 | *data = mapper; | |
8439 | } | |
1a93f8bd | 8440 | |
6e444319 | 8441 | return ftrace_func_mapper_add_ip(mapper, ip, init_data); |
1a93f8bd SRV |
8442 | } |
8443 | ||
8444 | static void | |
b5f081b5 | 8445 | ftrace_snapshot_free(struct ftrace_probe_ops *ops, struct trace_array *tr, |
6e444319 | 8446 | unsigned long ip, void *data) |
1a93f8bd | 8447 | { |
6e444319 SRV |
8448 | struct ftrace_func_mapper *mapper = data; |
8449 | ||
8450 | if (!ip) { | |
8451 | if (!mapper) | |
8452 | return; | |
8453 | free_ftrace_func_mapper(mapper, NULL); | |
8454 | return; | |
8455 | } | |
1a93f8bd SRV |
8456 | |
8457 | ftrace_func_mapper_remove_ip(mapper, ip); | |
8458 | } | |
8459 | ||
77fd5c15 SRRH |
8460 | static struct ftrace_probe_ops snapshot_probe_ops = { |
8461 | .func = ftrace_snapshot, | |
8462 | .print = ftrace_snapshot_print, | |
8463 | }; | |
8464 | ||
8465 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
8466 | .func = ftrace_count_snapshot, | |
8467 | .print = ftrace_snapshot_print, | |
1a93f8bd SRV |
8468 | .init = ftrace_snapshot_init, |
8469 | .free = ftrace_snapshot_free, | |
77fd5c15 SRRH |
8470 | }; |
8471 | ||
8472 | static int | |
04ec7bb6 | 8473 | ftrace_trace_snapshot_callback(struct trace_array *tr, struct ftrace_hash *hash, |
77fd5c15 SRRH |
8474 | char *glob, char *cmd, char *param, int enable) |
8475 | { | |
8476 | struct ftrace_probe_ops *ops; | |
8477 | void *count = (void *)-1; | |
8478 | char *number; | |
8479 | int ret; | |
8480 | ||
0f179765 SRV |
8481 | if (!tr) |
8482 | return -ENODEV; | |
8483 | ||
77fd5c15 SRRH |
8484 | /* hash funcs only work with set_ftrace_filter */ |
8485 | if (!enable) | |
8486 | return -EINVAL; | |
8487 | ||
8488 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
8489 | ||
d3d532d7 | 8490 | if (glob[0] == '!') |
7b60f3d8 | 8491 | return unregister_ftrace_function_probe_func(glob+1, tr, ops); |
77fd5c15 SRRH |
8492 | |
8493 | if (!param) | |
8494 | goto out_reg; | |
8495 | ||
8496 | number = strsep(¶m, ":"); | |
8497 | ||
8498 | if (!strlen(number)) | |
8499 | goto out_reg; | |
8500 | ||
8501 | /* | |
8502 | * We use the callback data field (which is a pointer) | |
8503 | * as our counter. | |
8504 | */ | |
8505 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
8506 | if (ret) | |
8507 | return ret; | |
8508 | ||
8509 | out_reg: | |
2824f503 | 8510 | ret = tracing_alloc_snapshot_instance(tr); |
df62db5b SRV |
8511 | if (ret < 0) |
8512 | goto out; | |
77fd5c15 | 8513 | |
4c174688 | 8514 | ret = register_ftrace_function_probe(glob, tr, ops, count); |
77fd5c15 | 8515 | |
df62db5b | 8516 | out: |
77fd5c15 SRRH |
8517 | return ret < 0 ? ret : 0; |
8518 | } | |
8519 | ||
8520 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
8521 | .name = "snapshot", | |
8522 | .func = ftrace_trace_snapshot_callback, | |
8523 | }; | |
8524 | ||
38de93ab | 8525 | static __init int register_snapshot_cmd(void) |
77fd5c15 SRRH |
8526 | { |
8527 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
8528 | } | |
8529 | #else | |
38de93ab | 8530 | static inline __init int register_snapshot_cmd(void) { return 0; } |
77fd5c15 | 8531 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ |
bc0c38d1 | 8532 | |
7eeafbca | 8533 | static struct dentry *tracing_get_dentry(struct trace_array *tr) |
bc0c38d1 | 8534 | { |
8434dc93 SRRH |
8535 | if (WARN_ON(!tr->dir)) |
8536 | return ERR_PTR(-ENODEV); | |
8537 | ||
8538 | /* Top directory uses NULL as the parent */ | |
8539 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
8540 | return NULL; | |
8541 | ||
8542 | /* All sub buffers have a descriptor */ | |
2b6080f2 | 8543 | return tr->dir; |
bc0c38d1 SR |
8544 | } |
8545 | ||
2b6080f2 | 8546 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 8547 | { |
b04cc6b1 FW |
8548 | struct dentry *d_tracer; |
8549 | ||
2b6080f2 SR |
8550 | if (tr->percpu_dir) |
8551 | return tr->percpu_dir; | |
b04cc6b1 | 8552 | |
7eeafbca | 8553 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 8554 | if (IS_ERR(d_tracer)) |
b04cc6b1 FW |
8555 | return NULL; |
8556 | ||
8434dc93 | 8557 | tr->percpu_dir = tracefs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 8558 | |
24589e3a | 8559 | MEM_FAIL(!tr->percpu_dir, |
8434dc93 | 8560 | "Could not create tracefs directory 'per_cpu/%d'\n", cpu); |
b04cc6b1 | 8561 | |
2b6080f2 | 8562 | return tr->percpu_dir; |
b04cc6b1 FW |
8563 | } |
8564 | ||
649e9c70 ON |
8565 | static struct dentry * |
8566 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
8567 | void *data, long cpu, const struct file_operations *fops) | |
8568 | { | |
8569 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
8570 | ||
8571 | if (ret) /* See tracing_get_cpu() */ | |
7682c918 | 8572 | d_inode(ret)->i_cdev = (void *)(cpu + 1); |
649e9c70 ON |
8573 | return ret; |
8574 | } | |
8575 | ||
2b6080f2 | 8576 | static void |
8434dc93 | 8577 | tracing_init_tracefs_percpu(struct trace_array *tr, long cpu) |
b04cc6b1 | 8578 | { |
2b6080f2 | 8579 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 8580 | struct dentry *d_cpu; |
dd49a38c | 8581 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 8582 | |
0a3d7ce7 NK |
8583 | if (!d_percpu) |
8584 | return; | |
8585 | ||
dd49a38c | 8586 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8434dc93 | 8587 | d_cpu = tracefs_create_dir(cpu_dir, d_percpu); |
8656e7a2 | 8588 | if (!d_cpu) { |
a395d6a7 | 8589 | pr_warn("Could not create tracefs '%s' entry\n", cpu_dir); |
8656e7a2 FW |
8590 | return; |
8591 | } | |
b04cc6b1 | 8592 | |
8656e7a2 | 8593 | /* per cpu trace_pipe */ |
bd324cfc | 8594 | trace_create_cpu_file("trace_pipe", TRACE_MODE_READ, d_cpu, |
15544209 | 8595 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
8596 | |
8597 | /* per cpu trace */ | |
bd324cfc | 8598 | trace_create_cpu_file("trace", TRACE_MODE_WRITE, d_cpu, |
6484c71c | 8599 | tr, cpu, &tracing_fops); |
7f96f93f | 8600 | |
bd324cfc | 8601 | trace_create_cpu_file("trace_pipe_raw", TRACE_MODE_READ, d_cpu, |
46ef2be0 | 8602 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 8603 | |
bd324cfc | 8604 | trace_create_cpu_file("stats", TRACE_MODE_READ, d_cpu, |
4d3435b8 | 8605 | tr, cpu, &tracing_stats_fops); |
438ced17 | 8606 | |
bd324cfc | 8607 | trace_create_cpu_file("buffer_size_kb", TRACE_MODE_READ, d_cpu, |
0bc392ee | 8608 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
8609 | |
8610 | #ifdef CONFIG_TRACER_SNAPSHOT | |
bd324cfc | 8611 | trace_create_cpu_file("snapshot", TRACE_MODE_WRITE, d_cpu, |
6484c71c | 8612 | tr, cpu, &snapshot_fops); |
6de58e62 | 8613 | |
bd324cfc | 8614 | trace_create_cpu_file("snapshot_raw", TRACE_MODE_READ, d_cpu, |
46ef2be0 | 8615 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 8616 | #endif |
b04cc6b1 FW |
8617 | } |
8618 | ||
60a11774 SR |
8619 | #ifdef CONFIG_FTRACE_SELFTEST |
8620 | /* Let selftest have access to static functions in this file */ | |
8621 | #include "trace_selftest.c" | |
8622 | #endif | |
8623 | ||
577b785f SR |
8624 | static ssize_t |
8625 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
8626 | loff_t *ppos) | |
8627 | { | |
8628 | struct trace_option_dentry *topt = filp->private_data; | |
8629 | char *buf; | |
8630 | ||
8631 | if (topt->flags->val & topt->opt->bit) | |
8632 | buf = "1\n"; | |
8633 | else | |
8634 | buf = "0\n"; | |
8635 | ||
8636 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
8637 | } | |
8638 | ||
8639 | static ssize_t | |
8640 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
8641 | loff_t *ppos) | |
8642 | { | |
8643 | struct trace_option_dentry *topt = filp->private_data; | |
8644 | unsigned long val; | |
577b785f SR |
8645 | int ret; |
8646 | ||
22fe9b54 PH |
8647 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
8648 | if (ret) | |
577b785f SR |
8649 | return ret; |
8650 | ||
8d18eaaf LZ |
8651 | if (val != 0 && val != 1) |
8652 | return -EINVAL; | |
577b785f | 8653 | |
8d18eaaf | 8654 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 8655 | mutex_lock(&trace_types_lock); |
8c1a49ae | 8656 | ret = __set_tracer_option(topt->tr, topt->flags, |
c757bea9 | 8657 | topt->opt, !val); |
577b785f SR |
8658 | mutex_unlock(&trace_types_lock); |
8659 | if (ret) | |
8660 | return ret; | |
577b785f SR |
8661 | } |
8662 | ||
8663 | *ppos += cnt; | |
8664 | ||
8665 | return cnt; | |
8666 | } | |
8667 | ||
8668 | ||
8669 | static const struct file_operations trace_options_fops = { | |
8670 | .open = tracing_open_generic, | |
8671 | .read = trace_options_read, | |
8672 | .write = trace_options_write, | |
b444786f | 8673 | .llseek = generic_file_llseek, |
577b785f SR |
8674 | }; |
8675 | ||
9a38a885 SRRH |
8676 | /* |
8677 | * In order to pass in both the trace_array descriptor as well as the index | |
8678 | * to the flag that the trace option file represents, the trace_array | |
8679 | * has a character array of trace_flags_index[], which holds the index | |
8680 | * of the bit for the flag it represents. index[0] == 0, index[1] == 1, etc. | |
8681 | * The address of this character array is passed to the flag option file | |
8682 | * read/write callbacks. | |
8683 | * | |
8684 | * In order to extract both the index and the trace_array descriptor, | |
8685 | * get_tr_index() uses the following algorithm. | |
8686 | * | |
8687 | * idx = *ptr; | |
8688 | * | |
8689 | * As the pointer itself contains the address of the index (remember | |
8690 | * index[1] == 1). | |
8691 | * | |
8692 | * Then to get the trace_array descriptor, by subtracting that index | |
8693 | * from the ptr, we get to the start of the index itself. | |
8694 | * | |
8695 | * ptr - idx == &index[0] | |
8696 | * | |
8697 | * Then a simple container_of() from that pointer gets us to the | |
8698 | * trace_array descriptor. | |
8699 | */ | |
8700 | static void get_tr_index(void *data, struct trace_array **ptr, | |
8701 | unsigned int *pindex) | |
8702 | { | |
8703 | *pindex = *(unsigned char *)data; | |
8704 | ||
8705 | *ptr = container_of(data - *pindex, struct trace_array, | |
8706 | trace_flags_index); | |
8707 | } | |
8708 | ||
a8259075 SR |
8709 | static ssize_t |
8710 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
8711 | loff_t *ppos) | |
8712 | { | |
9a38a885 SRRH |
8713 | void *tr_index = filp->private_data; |
8714 | struct trace_array *tr; | |
8715 | unsigned int index; | |
a8259075 SR |
8716 | char *buf; |
8717 | ||
9a38a885 SRRH |
8718 | get_tr_index(tr_index, &tr, &index); |
8719 | ||
8720 | if (tr->trace_flags & (1 << index)) | |
a8259075 SR |
8721 | buf = "1\n"; |
8722 | else | |
8723 | buf = "0\n"; | |
8724 | ||
8725 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
8726 | } | |
8727 | ||
8728 | static ssize_t | |
8729 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
8730 | loff_t *ppos) | |
8731 | { | |
9a38a885 SRRH |
8732 | void *tr_index = filp->private_data; |
8733 | struct trace_array *tr; | |
8734 | unsigned int index; | |
a8259075 SR |
8735 | unsigned long val; |
8736 | int ret; | |
8737 | ||
9a38a885 SRRH |
8738 | get_tr_index(tr_index, &tr, &index); |
8739 | ||
22fe9b54 PH |
8740 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
8741 | if (ret) | |
a8259075 SR |
8742 | return ret; |
8743 | ||
f2d84b65 | 8744 | if (val != 0 && val != 1) |
a8259075 | 8745 | return -EINVAL; |
69d34da2 | 8746 | |
3a53acf1 | 8747 | mutex_lock(&event_mutex); |
69d34da2 | 8748 | mutex_lock(&trace_types_lock); |
2b6080f2 | 8749 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 8750 | mutex_unlock(&trace_types_lock); |
3a53acf1 | 8751 | mutex_unlock(&event_mutex); |
a8259075 | 8752 | |
613f04a0 SRRH |
8753 | if (ret < 0) |
8754 | return ret; | |
8755 | ||
a8259075 SR |
8756 | *ppos += cnt; |
8757 | ||
8758 | return cnt; | |
8759 | } | |
8760 | ||
a8259075 SR |
8761 | static const struct file_operations trace_options_core_fops = { |
8762 | .open = tracing_open_generic, | |
8763 | .read = trace_options_core_read, | |
8764 | .write = trace_options_core_write, | |
b444786f | 8765 | .llseek = generic_file_llseek, |
a8259075 SR |
8766 | }; |
8767 | ||
5452af66 | 8768 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 8769 | umode_t mode, |
5452af66 FW |
8770 | struct dentry *parent, |
8771 | void *data, | |
8772 | const struct file_operations *fops) | |
8773 | { | |
8774 | struct dentry *ret; | |
8775 | ||
8434dc93 | 8776 | ret = tracefs_create_file(name, mode, parent, data, fops); |
5452af66 | 8777 | if (!ret) |
a395d6a7 | 8778 | pr_warn("Could not create tracefs '%s' entry\n", name); |
5452af66 FW |
8779 | |
8780 | return ret; | |
8781 | } | |
8782 | ||
8783 | ||
2b6080f2 | 8784 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
8785 | { |
8786 | struct dentry *d_tracer; | |
a8259075 | 8787 | |
2b6080f2 SR |
8788 | if (tr->options) |
8789 | return tr->options; | |
a8259075 | 8790 | |
7eeafbca | 8791 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 8792 | if (IS_ERR(d_tracer)) |
a8259075 SR |
8793 | return NULL; |
8794 | ||
8434dc93 | 8795 | tr->options = tracefs_create_dir("options", d_tracer); |
2b6080f2 | 8796 | if (!tr->options) { |
a395d6a7 | 8797 | pr_warn("Could not create tracefs directory 'options'\n"); |
a8259075 SR |
8798 | return NULL; |
8799 | } | |
8800 | ||
2b6080f2 | 8801 | return tr->options; |
a8259075 SR |
8802 | } |
8803 | ||
577b785f | 8804 | static void |
2b6080f2 SR |
8805 | create_trace_option_file(struct trace_array *tr, |
8806 | struct trace_option_dentry *topt, | |
577b785f SR |
8807 | struct tracer_flags *flags, |
8808 | struct tracer_opt *opt) | |
8809 | { | |
8810 | struct dentry *t_options; | |
577b785f | 8811 | |
2b6080f2 | 8812 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
8813 | if (!t_options) |
8814 | return; | |
8815 | ||
8816 | topt->flags = flags; | |
8817 | topt->opt = opt; | |
2b6080f2 | 8818 | topt->tr = tr; |
577b785f | 8819 | |
bd324cfc SRV |
8820 | topt->entry = trace_create_file(opt->name, TRACE_MODE_WRITE, |
8821 | t_options, topt, &trace_options_fops); | |
577b785f | 8822 | |
577b785f SR |
8823 | } |
8824 | ||
37aea98b | 8825 | static void |
2b6080f2 | 8826 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
8827 | { |
8828 | struct trace_option_dentry *topts; | |
37aea98b | 8829 | struct trace_options *tr_topts; |
577b785f SR |
8830 | struct tracer_flags *flags; |
8831 | struct tracer_opt *opts; | |
8832 | int cnt; | |
37aea98b | 8833 | int i; |
577b785f SR |
8834 | |
8835 | if (!tracer) | |
37aea98b | 8836 | return; |
577b785f SR |
8837 | |
8838 | flags = tracer->flags; | |
8839 | ||
8840 | if (!flags || !flags->opts) | |
37aea98b SRRH |
8841 | return; |
8842 | ||
8843 | /* | |
8844 | * If this is an instance, only create flags for tracers | |
8845 | * the instance may have. | |
8846 | */ | |
8847 | if (!trace_ok_for_array(tracer, tr)) | |
8848 | return; | |
8849 | ||
8850 | for (i = 0; i < tr->nr_topts; i++) { | |
d39cdd20 CH |
8851 | /* Make sure there's no duplicate flags. */ |
8852 | if (WARN_ON_ONCE(tr->topts[i].tracer->flags == tracer->flags)) | |
37aea98b SRRH |
8853 | return; |
8854 | } | |
577b785f SR |
8855 | |
8856 | opts = flags->opts; | |
8857 | ||
8858 | for (cnt = 0; opts[cnt].name; cnt++) | |
8859 | ; | |
8860 | ||
0cfe8245 | 8861 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f | 8862 | if (!topts) |
37aea98b SRRH |
8863 | return; |
8864 | ||
8865 | tr_topts = krealloc(tr->topts, sizeof(*tr->topts) * (tr->nr_topts + 1), | |
8866 | GFP_KERNEL); | |
8867 | if (!tr_topts) { | |
8868 | kfree(topts); | |
8869 | return; | |
8870 | } | |
8871 | ||
8872 | tr->topts = tr_topts; | |
8873 | tr->topts[tr->nr_topts].tracer = tracer; | |
8874 | tr->topts[tr->nr_topts].topts = topts; | |
8875 | tr->nr_topts++; | |
577b785f | 8876 | |
41d9c0be | 8877 | for (cnt = 0; opts[cnt].name; cnt++) { |
2b6080f2 | 8878 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f | 8879 | &opts[cnt]); |
24589e3a | 8880 | MEM_FAIL(topts[cnt].entry == NULL, |
41d9c0be SRRH |
8881 | "Failed to create trace option: %s", |
8882 | opts[cnt].name); | |
8883 | } | |
577b785f SR |
8884 | } |
8885 | ||
a8259075 | 8886 | static struct dentry * |
2b6080f2 SR |
8887 | create_trace_option_core_file(struct trace_array *tr, |
8888 | const char *option, long index) | |
a8259075 SR |
8889 | { |
8890 | struct dentry *t_options; | |
a8259075 | 8891 | |
2b6080f2 | 8892 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
8893 | if (!t_options) |
8894 | return NULL; | |
8895 | ||
bd324cfc | 8896 | return trace_create_file(option, TRACE_MODE_WRITE, t_options, |
9a38a885 SRRH |
8897 | (void *)&tr->trace_flags_index[index], |
8898 | &trace_options_core_fops); | |
a8259075 SR |
8899 | } |
8900 | ||
16270145 | 8901 | static void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
8902 | { |
8903 | struct dentry *t_options; | |
16270145 | 8904 | bool top_level = tr == &global_trace; |
a8259075 SR |
8905 | int i; |
8906 | ||
2b6080f2 | 8907 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
8908 | if (!t_options) |
8909 | return; | |
8910 | ||
16270145 SRRH |
8911 | for (i = 0; trace_options[i]; i++) { |
8912 | if (top_level || | |
8913 | !((1 << i) & TOP_LEVEL_TRACE_FLAGS)) | |
8914 | create_trace_option_core_file(tr, trace_options[i], i); | |
8915 | } | |
a8259075 SR |
8916 | } |
8917 | ||
499e5470 SR |
8918 | static ssize_t |
8919 | rb_simple_read(struct file *filp, char __user *ubuf, | |
8920 | size_t cnt, loff_t *ppos) | |
8921 | { | |
348f0fc2 | 8922 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
8923 | char buf[64]; |
8924 | int r; | |
8925 | ||
10246fa3 | 8926 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
8927 | r = sprintf(buf, "%d\n", r); |
8928 | ||
8929 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
8930 | } | |
8931 | ||
8932 | static ssize_t | |
8933 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
8934 | size_t cnt, loff_t *ppos) | |
8935 | { | |
348f0fc2 | 8936 | struct trace_array *tr = filp->private_data; |
13292494 | 8937 | struct trace_buffer *buffer = tr->array_buffer.buffer; |
499e5470 SR |
8938 | unsigned long val; |
8939 | int ret; | |
8940 | ||
8941 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
8942 | if (ret) | |
8943 | return ret; | |
8944 | ||
8945 | if (buffer) { | |
2df8f8a6 | 8946 | mutex_lock(&trace_types_lock); |
f143641b SRV |
8947 | if (!!val == tracer_tracing_is_on(tr)) { |
8948 | val = 0; /* do nothing */ | |
8949 | } else if (val) { | |
10246fa3 | 8950 | tracer_tracing_on(tr); |
2b6080f2 SR |
8951 | if (tr->current_trace->start) |
8952 | tr->current_trace->start(tr); | |
2df8f8a6 | 8953 | } else { |
10246fa3 | 8954 | tracer_tracing_off(tr); |
2b6080f2 SR |
8955 | if (tr->current_trace->stop) |
8956 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
8957 | } |
8958 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
8959 | } |
8960 | ||
8961 | (*ppos)++; | |
8962 | ||
8963 | return cnt; | |
8964 | } | |
8965 | ||
8966 | static const struct file_operations rb_simple_fops = { | |
7b85af63 | 8967 | .open = tracing_open_generic_tr, |
499e5470 SR |
8968 | .read = rb_simple_read, |
8969 | .write = rb_simple_write, | |
7b85af63 | 8970 | .release = tracing_release_generic_tr, |
499e5470 SR |
8971 | .llseek = default_llseek, |
8972 | }; | |
8973 | ||
03329f99 SRV |
8974 | static ssize_t |
8975 | buffer_percent_read(struct file *filp, char __user *ubuf, | |
8976 | size_t cnt, loff_t *ppos) | |
8977 | { | |
8978 | struct trace_array *tr = filp->private_data; | |
8979 | char buf[64]; | |
8980 | int r; | |
8981 | ||
8982 | r = tr->buffer_percent; | |
8983 | r = sprintf(buf, "%d\n", r); | |
8984 | ||
8985 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
8986 | } | |
8987 | ||
8988 | static ssize_t | |
8989 | buffer_percent_write(struct file *filp, const char __user *ubuf, | |
8990 | size_t cnt, loff_t *ppos) | |
8991 | { | |
8992 | struct trace_array *tr = filp->private_data; | |
8993 | unsigned long val; | |
8994 | int ret; | |
8995 | ||
8996 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
8997 | if (ret) | |
8998 | return ret; | |
8999 | ||
9000 | if (val > 100) | |
9001 | return -EINVAL; | |
9002 | ||
9003 | if (!val) | |
9004 | val = 1; | |
9005 | ||
9006 | tr->buffer_percent = val; | |
9007 | ||
9008 | (*ppos)++; | |
9009 | ||
9010 | return cnt; | |
9011 | } | |
9012 | ||
9013 | static const struct file_operations buffer_percent_fops = { | |
9014 | .open = tracing_open_generic_tr, | |
9015 | .read = buffer_percent_read, | |
9016 | .write = buffer_percent_write, | |
9017 | .release = tracing_release_generic_tr, | |
9018 | .llseek = default_llseek, | |
9019 | }; | |
9020 | ||
ff585c5b | 9021 | static struct dentry *trace_instance_dir; |
277ba044 SR |
9022 | |
9023 | static void | |
8434dc93 | 9024 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer); |
277ba044 | 9025 | |
55034cd6 | 9026 | static int |
1c5eb448 | 9027 | allocate_trace_buffer(struct trace_array *tr, struct array_buffer *buf, int size) |
277ba044 SR |
9028 | { |
9029 | enum ring_buffer_flags rb_flags; | |
737223fb | 9030 | |
983f938a | 9031 | rb_flags = tr->trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; |
737223fb | 9032 | |
dced341b SRRH |
9033 | buf->tr = tr; |
9034 | ||
55034cd6 SRRH |
9035 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
9036 | if (!buf->buffer) | |
9037 | return -ENOMEM; | |
737223fb | 9038 | |
55034cd6 SRRH |
9039 | buf->data = alloc_percpu(struct trace_array_cpu); |
9040 | if (!buf->data) { | |
9041 | ring_buffer_free(buf->buffer); | |
4397f045 | 9042 | buf->buffer = NULL; |
55034cd6 SRRH |
9043 | return -ENOMEM; |
9044 | } | |
737223fb | 9045 | |
737223fb | 9046 | /* Allocate the first page for all buffers */ |
1c5eb448 SRV |
9047 | set_buffer_entries(&tr->array_buffer, |
9048 | ring_buffer_size(tr->array_buffer.buffer, 0)); | |
737223fb | 9049 | |
55034cd6 SRRH |
9050 | return 0; |
9051 | } | |
737223fb | 9052 | |
55034cd6 SRRH |
9053 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
9054 | { | |
9055 | int ret; | |
737223fb | 9056 | |
1c5eb448 | 9057 | ret = allocate_trace_buffer(tr, &tr->array_buffer, size); |
55034cd6 SRRH |
9058 | if (ret) |
9059 | return ret; | |
737223fb | 9060 | |
55034cd6 SRRH |
9061 | #ifdef CONFIG_TRACER_MAX_TRACE |
9062 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
9063 | allocate_snapshot ? size : 1); | |
24589e3a | 9064 | if (MEM_FAIL(ret, "Failed to allocate trace buffer\n")) { |
1c5eb448 SRV |
9065 | ring_buffer_free(tr->array_buffer.buffer); |
9066 | tr->array_buffer.buffer = NULL; | |
9067 | free_percpu(tr->array_buffer.data); | |
9068 | tr->array_buffer.data = NULL; | |
55034cd6 SRRH |
9069 | return -ENOMEM; |
9070 | } | |
9071 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 9072 | |
55034cd6 SRRH |
9073 | /* |
9074 | * Only the top level trace array gets its snapshot allocated | |
9075 | * from the kernel command line. | |
9076 | */ | |
9077 | allocate_snapshot = false; | |
737223fb | 9078 | #endif |
11f5efc3 | 9079 | |
55034cd6 | 9080 | return 0; |
737223fb SRRH |
9081 | } |
9082 | ||
1c5eb448 | 9083 | static void free_trace_buffer(struct array_buffer *buf) |
f0b70cc4 SRRH |
9084 | { |
9085 | if (buf->buffer) { | |
9086 | ring_buffer_free(buf->buffer); | |
9087 | buf->buffer = NULL; | |
9088 | free_percpu(buf->data); | |
9089 | buf->data = NULL; | |
9090 | } | |
9091 | } | |
9092 | ||
23aaa3c1 SRRH |
9093 | static void free_trace_buffers(struct trace_array *tr) |
9094 | { | |
9095 | if (!tr) | |
9096 | return; | |
9097 | ||
1c5eb448 | 9098 | free_trace_buffer(&tr->array_buffer); |
23aaa3c1 SRRH |
9099 | |
9100 | #ifdef CONFIG_TRACER_MAX_TRACE | |
f0b70cc4 | 9101 | free_trace_buffer(&tr->max_buffer); |
23aaa3c1 SRRH |
9102 | #endif |
9103 | } | |
9104 | ||
9a38a885 SRRH |
9105 | static void init_trace_flags_index(struct trace_array *tr) |
9106 | { | |
9107 | int i; | |
9108 | ||
9109 | /* Used by the trace options files */ | |
9110 | for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++) | |
9111 | tr->trace_flags_index[i] = i; | |
9112 | } | |
9113 | ||
37aea98b SRRH |
9114 | static void __update_tracer_options(struct trace_array *tr) |
9115 | { | |
9116 | struct tracer *t; | |
9117 | ||
9118 | for (t = trace_types; t; t = t->next) | |
9119 | add_tracer_options(tr, t); | |
9120 | } | |
9121 | ||
9122 | static void update_tracer_options(struct trace_array *tr) | |
9123 | { | |
9124 | mutex_lock(&trace_types_lock); | |
9125 | __update_tracer_options(tr); | |
9126 | mutex_unlock(&trace_types_lock); | |
9127 | } | |
9128 | ||
89c95fce TZ |
9129 | /* Must have trace_types_lock held */ |
9130 | struct trace_array *trace_array_find(const char *instance) | |
9131 | { | |
9132 | struct trace_array *tr, *found = NULL; | |
9133 | ||
9134 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
9135 | if (tr->name && strcmp(tr->name, instance) == 0) { | |
9136 | found = tr; | |
9137 | break; | |
9138 | } | |
9139 | } | |
9140 | ||
9141 | return found; | |
9142 | } | |
9143 | ||
9144 | struct trace_array *trace_array_find_get(const char *instance) | |
9145 | { | |
9146 | struct trace_array *tr; | |
9147 | ||
9148 | mutex_lock(&trace_types_lock); | |
9149 | tr = trace_array_find(instance); | |
9150 | if (tr) | |
9151 | tr->ref++; | |
9152 | mutex_unlock(&trace_types_lock); | |
9153 | ||
9154 | return tr; | |
9155 | } | |
9156 | ||
4114fbfd MH |
9157 | static int trace_array_create_dir(struct trace_array *tr) |
9158 | { | |
9159 | int ret; | |
9160 | ||
9161 | tr->dir = tracefs_create_dir(tr->name, trace_instance_dir); | |
9162 | if (!tr->dir) | |
9163 | return -EINVAL; | |
9164 | ||
9165 | ret = event_trace_add_tracer(tr->dir, tr); | |
ff41c28c | 9166 | if (ret) { |
4114fbfd | 9167 | tracefs_remove(tr->dir); |
ff41c28c KA |
9168 | return ret; |
9169 | } | |
4114fbfd MH |
9170 | |
9171 | init_tracer_tracefs(tr, tr->dir); | |
9172 | __update_tracer_options(tr); | |
9173 | ||
9174 | return ret; | |
9175 | } | |
9176 | ||
28879787 | 9177 | static struct trace_array *trace_array_create(const char *name) |
737223fb | 9178 | { |
277ba044 SR |
9179 | struct trace_array *tr; |
9180 | int ret; | |
277ba044 | 9181 | |
277ba044 SR |
9182 | ret = -ENOMEM; |
9183 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
9184 | if (!tr) | |
28879787 | 9185 | return ERR_PTR(ret); |
277ba044 SR |
9186 | |
9187 | tr->name = kstrdup(name, GFP_KERNEL); | |
9188 | if (!tr->name) | |
9189 | goto out_free_tr; | |
9190 | ||
ccfe9e42 AL |
9191 | if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) |
9192 | goto out_free_tr; | |
9193 | ||
20550622 | 9194 | tr->trace_flags = global_trace.trace_flags & ~ZEROED_TRACE_FLAGS; |
983f938a | 9195 | |
ccfe9e42 AL |
9196 | cpumask_copy(tr->tracing_cpumask, cpu_all_mask); |
9197 | ||
277ba044 SR |
9198 | raw_spin_lock_init(&tr->start_lock); |
9199 | ||
0b9b12c1 SRRH |
9200 | tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
9201 | ||
277ba044 SR |
9202 | tr->current_trace = &nop_trace; |
9203 | ||
9204 | INIT_LIST_HEAD(&tr->systems); | |
9205 | INIT_LIST_HEAD(&tr->events); | |
067fe038 | 9206 | INIT_LIST_HEAD(&tr->hist_vars); |
2f754e77 | 9207 | INIT_LIST_HEAD(&tr->err_log); |
277ba044 | 9208 | |
737223fb | 9209 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
9210 | goto out_free_tr; |
9211 | ||
4114fbfd | 9212 | if (ftrace_allocate_ftrace_ops(tr) < 0) |
277ba044 SR |
9213 | goto out_free_tr; |
9214 | ||
04ec7bb6 SRV |
9215 | ftrace_init_trace_array(tr); |
9216 | ||
9a38a885 | 9217 | init_trace_flags_index(tr); |
4114fbfd MH |
9218 | |
9219 | if (trace_instance_dir) { | |
9220 | ret = trace_array_create_dir(tr); | |
9221 | if (ret) | |
9222 | goto out_free_tr; | |
720dee53 MH |
9223 | } else |
9224 | __trace_early_add_events(tr); | |
277ba044 SR |
9225 | |
9226 | list_add(&tr->list, &ftrace_trace_arrays); | |
9227 | ||
28879787 DI |
9228 | tr->ref++; |
9229 | ||
f45d1225 | 9230 | return tr; |
277ba044 SR |
9231 | |
9232 | out_free_tr: | |
4114fbfd | 9233 | ftrace_free_ftrace_ops(tr); |
23aaa3c1 | 9234 | free_trace_buffers(tr); |
ccfe9e42 | 9235 | free_cpumask_var(tr->tracing_cpumask); |
277ba044 SR |
9236 | kfree(tr->name); |
9237 | kfree(tr); | |
9238 | ||
f45d1225 DI |
9239 | return ERR_PTR(ret); |
9240 | } | |
277ba044 | 9241 | |
f45d1225 DI |
9242 | static int instance_mkdir(const char *name) |
9243 | { | |
28879787 DI |
9244 | struct trace_array *tr; |
9245 | int ret; | |
9246 | ||
9247 | mutex_lock(&event_mutex); | |
9248 | mutex_lock(&trace_types_lock); | |
9249 | ||
9250 | ret = -EEXIST; | |
89c95fce TZ |
9251 | if (trace_array_find(name)) |
9252 | goto out_unlock; | |
28879787 DI |
9253 | |
9254 | tr = trace_array_create(name); | |
9255 | ||
9256 | ret = PTR_ERR_OR_ZERO(tr); | |
9257 | ||
9258 | out_unlock: | |
9259 | mutex_unlock(&trace_types_lock); | |
9260 | mutex_unlock(&event_mutex); | |
9261 | return ret; | |
9262 | } | |
9263 | ||
9264 | /** | |
9265 | * trace_array_get_by_name - Create/Lookup a trace array, given its name. | |
9266 | * @name: The name of the trace array to be looked up/created. | |
9267 | * | |
9268 | * Returns pointer to trace array with given name. | |
9269 | * NULL, if it cannot be created. | |
9270 | * | |
9271 | * NOTE: This function increments the reference counter associated with the | |
9272 | * trace array returned. This makes sure it cannot be freed while in use. | |
9273 | * Use trace_array_put() once the trace array is no longer needed. | |
28394da2 SRV |
9274 | * If the trace_array is to be freed, trace_array_destroy() needs to |
9275 | * be called after the trace_array_put(), or simply let user space delete | |
9276 | * it from the tracefs instances directory. But until the | |
9277 | * trace_array_put() is called, user space can not delete it. | |
28879787 DI |
9278 | * |
9279 | */ | |
9280 | struct trace_array *trace_array_get_by_name(const char *name) | |
9281 | { | |
9282 | struct trace_array *tr; | |
9283 | ||
9284 | mutex_lock(&event_mutex); | |
9285 | mutex_lock(&trace_types_lock); | |
9286 | ||
9287 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
9288 | if (tr->name && strcmp(tr->name, name) == 0) | |
9289 | goto out_unlock; | |
9290 | } | |
9291 | ||
9292 | tr = trace_array_create(name); | |
9293 | ||
9294 | if (IS_ERR(tr)) | |
9295 | tr = NULL; | |
9296 | out_unlock: | |
9297 | if (tr) | |
9298 | tr->ref++; | |
9299 | ||
9300 | mutex_unlock(&trace_types_lock); | |
9301 | mutex_unlock(&event_mutex); | |
9302 | return tr; | |
277ba044 | 9303 | } |
28879787 | 9304 | EXPORT_SYMBOL_GPL(trace_array_get_by_name); |
277ba044 | 9305 | |
f45d1225 | 9306 | static int __remove_instance(struct trace_array *tr) |
0c8916c3 | 9307 | { |
37aea98b | 9308 | int i; |
0c8916c3 | 9309 | |
28879787 | 9310 | /* Reference counter for a newly created trace array = 1. */ |
7ef282e0 | 9311 | if (tr->ref > 1 || (tr->current_trace && tr->trace_ref)) |
f45d1225 | 9312 | return -EBUSY; |
a695cb58 | 9313 | |
0c8916c3 SR |
9314 | list_del(&tr->list); |
9315 | ||
20550622 SRRH |
9316 | /* Disable all the flags that were enabled coming in */ |
9317 | for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++) { | |
9318 | if ((1 << i) & ZEROED_TRACE_FLAGS) | |
9319 | set_tracer_flag(tr, 1 << i, 0); | |
9320 | } | |
9321 | ||
6b450d25 | 9322 | tracing_set_nop(tr); |
a0e6369e | 9323 | clear_ftrace_function_probes(tr); |
0c8916c3 | 9324 | event_trace_del_tracer(tr); |
d879d0b8 | 9325 | ftrace_clear_pids(tr); |
591dffda | 9326 | ftrace_destroy_function_files(tr); |
a3d1e7eb | 9327 | tracefs_remove(tr->dir); |
20344c54 | 9328 | free_percpu(tr->last_func_repeats); |
a9fcaaac | 9329 | free_trace_buffers(tr); |
0c8916c3 | 9330 | |
37aea98b SRRH |
9331 | for (i = 0; i < tr->nr_topts; i++) { |
9332 | kfree(tr->topts[i].topts); | |
9333 | } | |
9334 | kfree(tr->topts); | |
9335 | ||
db9108e0 | 9336 | free_cpumask_var(tr->tracing_cpumask); |
0c8916c3 SR |
9337 | kfree(tr->name); |
9338 | kfree(tr); | |
9339 | ||
f45d1225 DI |
9340 | return 0; |
9341 | } | |
9342 | ||
e585e646 | 9343 | int trace_array_destroy(struct trace_array *this_tr) |
f45d1225 | 9344 | { |
e585e646 | 9345 | struct trace_array *tr; |
f45d1225 DI |
9346 | int ret; |
9347 | ||
e585e646 | 9348 | if (!this_tr) |
f45d1225 DI |
9349 | return -EINVAL; |
9350 | ||
9351 | mutex_lock(&event_mutex); | |
9352 | mutex_lock(&trace_types_lock); | |
9353 | ||
e585e646 DI |
9354 | ret = -ENODEV; |
9355 | ||
9356 | /* Making sure trace array exists before destroying it. */ | |
9357 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
9358 | if (tr == this_tr) { | |
9359 | ret = __remove_instance(tr); | |
9360 | break; | |
9361 | } | |
9362 | } | |
f45d1225 DI |
9363 | |
9364 | mutex_unlock(&trace_types_lock); | |
9365 | mutex_unlock(&event_mutex); | |
9366 | ||
9367 | return ret; | |
9368 | } | |
9369 | EXPORT_SYMBOL_GPL(trace_array_destroy); | |
9370 | ||
9371 | static int instance_rmdir(const char *name) | |
9372 | { | |
9373 | struct trace_array *tr; | |
9374 | int ret; | |
9375 | ||
9376 | mutex_lock(&event_mutex); | |
9377 | mutex_lock(&trace_types_lock); | |
9378 | ||
9379 | ret = -ENODEV; | |
89c95fce TZ |
9380 | tr = trace_array_find(name); |
9381 | if (tr) | |
9382 | ret = __remove_instance(tr); | |
0c8916c3 | 9383 | |
0c8916c3 | 9384 | mutex_unlock(&trace_types_lock); |
12ecef0c | 9385 | mutex_unlock(&event_mutex); |
0c8916c3 SR |
9386 | |
9387 | return ret; | |
9388 | } | |
9389 | ||
277ba044 SR |
9390 | static __init void create_trace_instances(struct dentry *d_tracer) |
9391 | { | |
4114fbfd MH |
9392 | struct trace_array *tr; |
9393 | ||
eae47358 SRRH |
9394 | trace_instance_dir = tracefs_create_instance_dir("instances", d_tracer, |
9395 | instance_mkdir, | |
9396 | instance_rmdir); | |
24589e3a | 9397 | if (MEM_FAIL(!trace_instance_dir, "Failed to create instances directory\n")) |
277ba044 | 9398 | return; |
4114fbfd MH |
9399 | |
9400 | mutex_lock(&event_mutex); | |
9401 | mutex_lock(&trace_types_lock); | |
9402 | ||
9403 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
9404 | if (!tr->name) | |
9405 | continue; | |
9406 | if (MEM_FAIL(trace_array_create_dir(tr) < 0, | |
9407 | "Failed to create instance directory\n")) | |
9408 | break; | |
9409 | } | |
9410 | ||
9411 | mutex_unlock(&trace_types_lock); | |
9412 | mutex_unlock(&event_mutex); | |
277ba044 SR |
9413 | } |
9414 | ||
2b6080f2 | 9415 | static void |
8434dc93 | 9416 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
2b6080f2 | 9417 | { |
3dd80953 | 9418 | struct trace_event_file *file; |
121aaee7 | 9419 | int cpu; |
2b6080f2 | 9420 | |
bd324cfc | 9421 | trace_create_file("available_tracers", TRACE_MODE_READ, d_tracer, |
607e2ea1 SRRH |
9422 | tr, &show_traces_fops); |
9423 | ||
bd324cfc | 9424 | trace_create_file("current_tracer", TRACE_MODE_WRITE, d_tracer, |
607e2ea1 SRRH |
9425 | tr, &set_tracer_fops); |
9426 | ||
bd324cfc | 9427 | trace_create_file("tracing_cpumask", TRACE_MODE_WRITE, d_tracer, |
ccfe9e42 AL |
9428 | tr, &tracing_cpumask_fops); |
9429 | ||
bd324cfc | 9430 | trace_create_file("trace_options", TRACE_MODE_WRITE, d_tracer, |
2b6080f2 SR |
9431 | tr, &tracing_iter_fops); |
9432 | ||
bd324cfc | 9433 | trace_create_file("trace", TRACE_MODE_WRITE, d_tracer, |
6484c71c | 9434 | tr, &tracing_fops); |
2b6080f2 | 9435 | |
bd324cfc | 9436 | trace_create_file("trace_pipe", TRACE_MODE_READ, d_tracer, |
15544209 | 9437 | tr, &tracing_pipe_fops); |
2b6080f2 | 9438 | |
bd324cfc | 9439 | trace_create_file("buffer_size_kb", TRACE_MODE_WRITE, d_tracer, |
0bc392ee | 9440 | tr, &tracing_entries_fops); |
2b6080f2 | 9441 | |
bd324cfc | 9442 | trace_create_file("buffer_total_size_kb", TRACE_MODE_READ, d_tracer, |
2b6080f2 SR |
9443 | tr, &tracing_total_entries_fops); |
9444 | ||
238ae93d | 9445 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
9446 | tr, &tracing_free_buffer_fops); |
9447 | ||
9448 | trace_create_file("trace_marker", 0220, d_tracer, | |
9449 | tr, &tracing_mark_fops); | |
9450 | ||
3dd80953 SRV |
9451 | file = __find_event_file(tr, "ftrace", "print"); |
9452 | if (file && file->dir) | |
bd324cfc SRV |
9453 | trace_create_file("trigger", TRACE_MODE_WRITE, file->dir, |
9454 | file, &event_trigger_fops); | |
3dd80953 SRV |
9455 | tr->trace_marker_file = file; |
9456 | ||
fa32e855 SR |
9457 | trace_create_file("trace_marker_raw", 0220, d_tracer, |
9458 | tr, &tracing_mark_raw_fops); | |
9459 | ||
bd324cfc | 9460 | trace_create_file("trace_clock", TRACE_MODE_WRITE, d_tracer, tr, |
2b6080f2 SR |
9461 | &trace_clock_fops); |
9462 | ||
bd324cfc | 9463 | trace_create_file("tracing_on", TRACE_MODE_WRITE, d_tracer, |
6484c71c | 9464 | tr, &rb_simple_fops); |
ce9bae55 | 9465 | |
bd324cfc | 9466 | trace_create_file("timestamp_mode", TRACE_MODE_READ, d_tracer, tr, |
2c1ea60b TZ |
9467 | &trace_time_stamp_mode_fops); |
9468 | ||
a7b1d74e | 9469 | tr->buffer_percent = 50; |
03329f99 | 9470 | |
bd324cfc | 9471 | trace_create_file("buffer_percent", TRACE_MODE_READ, d_tracer, |
03329f99 SRV |
9472 | tr, &buffer_percent_fops); |
9473 | ||
16270145 SRRH |
9474 | create_trace_options_dir(tr); |
9475 | ||
91edde2e | 9476 | trace_create_maxlat_file(tr, d_tracer); |
6d9b3fa5 | 9477 | |
591dffda | 9478 | if (ftrace_create_function_files(tr, d_tracer)) |
24589e3a | 9479 | MEM_FAIL(1, "Could not allocate function filter files"); |
591dffda | 9480 | |
ce9bae55 | 9481 | #ifdef CONFIG_TRACER_SNAPSHOT |
bd324cfc | 9482 | trace_create_file("snapshot", TRACE_MODE_WRITE, d_tracer, |
6484c71c | 9483 | tr, &snapshot_fops); |
ce9bae55 | 9484 | #endif |
121aaee7 | 9485 | |
bd324cfc | 9486 | trace_create_file("error_log", TRACE_MODE_WRITE, d_tracer, |
8a062902 TZ |
9487 | tr, &tracing_err_log_fops); |
9488 | ||
121aaee7 | 9489 | for_each_tracing_cpu(cpu) |
8434dc93 | 9490 | tracing_init_tracefs_percpu(tr, cpu); |
121aaee7 | 9491 | |
345ddcc8 | 9492 | ftrace_init_tracefs(tr, d_tracer); |
2b6080f2 SR |
9493 | } |
9494 | ||
93faccbb | 9495 | static struct vfsmount *trace_automount(struct dentry *mntpt, void *ingore) |
f76180bc SRRH |
9496 | { |
9497 | struct vfsmount *mnt; | |
9498 | struct file_system_type *type; | |
9499 | ||
9500 | /* | |
9501 | * To maintain backward compatibility for tools that mount | |
9502 | * debugfs to get to the tracing facility, tracefs is automatically | |
9503 | * mounted to the debugfs/tracing directory. | |
9504 | */ | |
9505 | type = get_fs_type("tracefs"); | |
9506 | if (!type) | |
9507 | return NULL; | |
93faccbb | 9508 | mnt = vfs_submount(mntpt, type, "tracefs", NULL); |
f76180bc SRRH |
9509 | put_filesystem(type); |
9510 | if (IS_ERR(mnt)) | |
9511 | return NULL; | |
9512 | mntget(mnt); | |
9513 | ||
9514 | return mnt; | |
9515 | } | |
9516 | ||
7eeafbca SRRH |
9517 | /** |
9518 | * tracing_init_dentry - initialize top level trace array | |
9519 | * | |
9520 | * This is called when creating files or directories in the tracing | |
9521 | * directory. It is called via fs_initcall() by any of the boot up code | |
9522 | * and expects to return the dentry of the top level tracing directory. | |
9523 | */ | |
22c36b18 | 9524 | int tracing_init_dentry(void) |
7eeafbca SRRH |
9525 | { |
9526 | struct trace_array *tr = &global_trace; | |
9527 | ||
a356646a | 9528 | if (security_locked_down(LOCKDOWN_TRACEFS)) { |
ee195452 | 9529 | pr_warn("Tracing disabled due to lockdown\n"); |
22c36b18 | 9530 | return -EPERM; |
a356646a SRV |
9531 | } |
9532 | ||
f76180bc | 9533 | /* The top level trace array uses NULL as parent */ |
7eeafbca | 9534 | if (tr->dir) |
22c36b18 | 9535 | return 0; |
7eeafbca | 9536 | |
072e133d | 9537 | if (WARN_ON(!tracefs_initialized())) |
22c36b18 | 9538 | return -ENODEV; |
7eeafbca | 9539 | |
f76180bc SRRH |
9540 | /* |
9541 | * As there may still be users that expect the tracing | |
9542 | * files to exist in debugfs/tracing, we must automount | |
9543 | * the tracefs file system there, so older tools still | |
f2cc020d | 9544 | * work with the newer kernel. |
f76180bc SRRH |
9545 | */ |
9546 | tr->dir = debugfs_create_automount("tracing", NULL, | |
9547 | trace_automount, NULL); | |
7eeafbca | 9548 | |
22c36b18 | 9549 | return 0; |
7eeafbca SRRH |
9550 | } |
9551 | ||
00f4b652 JL |
9552 | extern struct trace_eval_map *__start_ftrace_eval_maps[]; |
9553 | extern struct trace_eval_map *__stop_ftrace_eval_maps[]; | |
0c564a53 | 9554 | |
f6a69466 SRV |
9555 | static struct workqueue_struct *eval_map_wq __initdata; |
9556 | static struct work_struct eval_map_work __initdata; | |
9557 | ||
9558 | static void __init eval_map_work_func(struct work_struct *work) | |
0c564a53 | 9559 | { |
3673b8e4 SRRH |
9560 | int len; |
9561 | ||
02fd7f68 | 9562 | len = __stop_ftrace_eval_maps - __start_ftrace_eval_maps; |
f57a4143 | 9563 | trace_insert_eval_map(NULL, __start_ftrace_eval_maps, len); |
3673b8e4 SRRH |
9564 | } |
9565 | ||
f6a69466 SRV |
9566 | static int __init trace_eval_init(void) |
9567 | { | |
9568 | INIT_WORK(&eval_map_work, eval_map_work_func); | |
9569 | ||
9570 | eval_map_wq = alloc_workqueue("eval_map_wq", WQ_UNBOUND, 0); | |
9571 | if (!eval_map_wq) { | |
9572 | pr_err("Unable to allocate eval_map_wq\n"); | |
9573 | /* Do work here */ | |
9574 | eval_map_work_func(&eval_map_work); | |
9575 | return -ENOMEM; | |
9576 | } | |
9577 | ||
9578 | queue_work(eval_map_wq, &eval_map_work); | |
9579 | return 0; | |
9580 | } | |
9581 | ||
9582 | static int __init trace_eval_sync(void) | |
9583 | { | |
9584 | /* Make sure the eval map updates are finished */ | |
9585 | if (eval_map_wq) | |
9586 | destroy_workqueue(eval_map_wq); | |
9587 | return 0; | |
9588 | } | |
9589 | ||
9590 | late_initcall_sync(trace_eval_sync); | |
9591 | ||
9592 | ||
3673b8e4 | 9593 | #ifdef CONFIG_MODULES |
f57a4143 | 9594 | static void trace_module_add_evals(struct module *mod) |
3673b8e4 | 9595 | { |
99be647c | 9596 | if (!mod->num_trace_evals) |
3673b8e4 SRRH |
9597 | return; |
9598 | ||
9599 | /* | |
9600 | * Modules with bad taint do not have events created, do | |
9601 | * not bother with enums either. | |
9602 | */ | |
9603 | if (trace_module_has_bad_taint(mod)) | |
9604 | return; | |
9605 | ||
f57a4143 | 9606 | trace_insert_eval_map(mod, mod->trace_evals, mod->num_trace_evals); |
3673b8e4 SRRH |
9607 | } |
9608 | ||
681bec03 | 9609 | #ifdef CONFIG_TRACE_EVAL_MAP_FILE |
f57a4143 | 9610 | static void trace_module_remove_evals(struct module *mod) |
9828413d | 9611 | { |
23bf8cb8 JL |
9612 | union trace_eval_map_item *map; |
9613 | union trace_eval_map_item **last = &trace_eval_maps; | |
9828413d | 9614 | |
99be647c | 9615 | if (!mod->num_trace_evals) |
9828413d SRRH |
9616 | return; |
9617 | ||
1793ed93 | 9618 | mutex_lock(&trace_eval_mutex); |
9828413d | 9619 | |
23bf8cb8 | 9620 | map = trace_eval_maps; |
9828413d SRRH |
9621 | |
9622 | while (map) { | |
9623 | if (map->head.mod == mod) | |
9624 | break; | |
5f60b351 | 9625 | map = trace_eval_jmp_to_tail(map); |
9828413d SRRH |
9626 | last = &map->tail.next; |
9627 | map = map->tail.next; | |
9628 | } | |
9629 | if (!map) | |
9630 | goto out; | |
9631 | ||
5f60b351 | 9632 | *last = trace_eval_jmp_to_tail(map)->tail.next; |
9828413d SRRH |
9633 | kfree(map); |
9634 | out: | |
1793ed93 | 9635 | mutex_unlock(&trace_eval_mutex); |
9828413d SRRH |
9636 | } |
9637 | #else | |
f57a4143 | 9638 | static inline void trace_module_remove_evals(struct module *mod) { } |
681bec03 | 9639 | #endif /* CONFIG_TRACE_EVAL_MAP_FILE */ |
9828413d | 9640 | |
3673b8e4 SRRH |
9641 | static int trace_module_notify(struct notifier_block *self, |
9642 | unsigned long val, void *data) | |
9643 | { | |
9644 | struct module *mod = data; | |
9645 | ||
9646 | switch (val) { | |
9647 | case MODULE_STATE_COMING: | |
f57a4143 | 9648 | trace_module_add_evals(mod); |
3673b8e4 | 9649 | break; |
9828413d | 9650 | case MODULE_STATE_GOING: |
f57a4143 | 9651 | trace_module_remove_evals(mod); |
9828413d | 9652 | break; |
3673b8e4 SRRH |
9653 | } |
9654 | ||
0340a6b7 | 9655 | return NOTIFY_OK; |
0c564a53 SRRH |
9656 | } |
9657 | ||
3673b8e4 SRRH |
9658 | static struct notifier_block trace_module_nb = { |
9659 | .notifier_call = trace_module_notify, | |
9660 | .priority = 0, | |
9661 | }; | |
9828413d | 9662 | #endif /* CONFIG_MODULES */ |
3673b8e4 | 9663 | |
8434dc93 | 9664 | static __init int tracer_init_tracefs(void) |
bc0c38d1 | 9665 | { |
22c36b18 | 9666 | int ret; |
bc0c38d1 | 9667 | |
7e53bd42 LJ |
9668 | trace_access_lock_init(); |
9669 | ||
22c36b18 WY |
9670 | ret = tracing_init_dentry(); |
9671 | if (ret) | |
ed6f1c99 | 9672 | return 0; |
bc0c38d1 | 9673 | |
58b92547 SRV |
9674 | event_trace_init(); |
9675 | ||
22c36b18 WY |
9676 | init_tracer_tracefs(&global_trace, NULL); |
9677 | ftrace_init_tracefs_toplevel(&global_trace, NULL); | |
bc0c38d1 | 9678 | |
bd324cfc | 9679 | trace_create_file("tracing_thresh", TRACE_MODE_WRITE, NULL, |
6508fa76 | 9680 | &global_trace, &tracing_thresh_fops); |
a8259075 | 9681 | |
bd324cfc | 9682 | trace_create_file("README", TRACE_MODE_READ, NULL, |
5452af66 FW |
9683 | NULL, &tracing_readme_fops); |
9684 | ||
bd324cfc | 9685 | trace_create_file("saved_cmdlines", TRACE_MODE_READ, NULL, |
69abe6a5 | 9686 | NULL, &tracing_saved_cmdlines_fops); |
5bf9a1ee | 9687 | |
bd324cfc | 9688 | trace_create_file("saved_cmdlines_size", TRACE_MODE_WRITE, NULL, |
939c7a4f YY |
9689 | NULL, &tracing_saved_cmdlines_size_fops); |
9690 | ||
bd324cfc | 9691 | trace_create_file("saved_tgids", TRACE_MODE_READ, NULL, |
99c621d7 MS |
9692 | NULL, &tracing_saved_tgids_fops); |
9693 | ||
5f60b351 | 9694 | trace_eval_init(); |
0c564a53 | 9695 | |
22c36b18 | 9696 | trace_create_eval_file(NULL); |
9828413d | 9697 | |
3673b8e4 SRRH |
9698 | #ifdef CONFIG_MODULES |
9699 | register_module_notifier(&trace_module_nb); | |
9700 | #endif | |
9701 | ||
bc0c38d1 | 9702 | #ifdef CONFIG_DYNAMIC_FTRACE |
bd324cfc | 9703 | trace_create_file("dyn_ftrace_total_info", TRACE_MODE_READ, NULL, |
da537f0a | 9704 | NULL, &tracing_dyn_info_fops); |
bc0c38d1 | 9705 | #endif |
b04cc6b1 | 9706 | |
22c36b18 | 9707 | create_trace_instances(NULL); |
5452af66 | 9708 | |
37aea98b | 9709 | update_tracer_options(&global_trace); |
09d23a1d | 9710 | |
b5ad384e | 9711 | return 0; |
bc0c38d1 SR |
9712 | } |
9713 | ||
f3860136 SRV |
9714 | fs_initcall(tracer_init_tracefs); |
9715 | ||
3f5a54e3 SR |
9716 | static int trace_panic_handler(struct notifier_block *this, |
9717 | unsigned long event, void *unused) | |
9718 | { | |
944ac425 | 9719 | if (ftrace_dump_on_oops) |
cecbca96 | 9720 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
9721 | return NOTIFY_OK; |
9722 | } | |
9723 | ||
9724 | static struct notifier_block trace_panic_notifier = { | |
9725 | .notifier_call = trace_panic_handler, | |
9726 | .next = NULL, | |
9727 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
9728 | }; | |
9729 | ||
9730 | static int trace_die_handler(struct notifier_block *self, | |
9731 | unsigned long val, | |
9732 | void *data) | |
9733 | { | |
9734 | switch (val) { | |
9735 | case DIE_OOPS: | |
944ac425 | 9736 | if (ftrace_dump_on_oops) |
cecbca96 | 9737 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
9738 | break; |
9739 | default: | |
9740 | break; | |
9741 | } | |
9742 | return NOTIFY_OK; | |
9743 | } | |
9744 | ||
9745 | static struct notifier_block trace_die_notifier = { | |
9746 | .notifier_call = trace_die_handler, | |
9747 | .priority = 200 | |
9748 | }; | |
9749 | ||
9750 | /* | |
9751 | * printk is set to max of 1024, we really don't need it that big. | |
9752 | * Nothing should be printing 1000 characters anyway. | |
9753 | */ | |
9754 | #define TRACE_MAX_PRINT 1000 | |
9755 | ||
9756 | /* | |
9757 | * Define here KERN_TRACE so that we have one place to modify | |
9758 | * it if we decide to change what log level the ftrace dump | |
9759 | * should be at. | |
9760 | */ | |
428aee14 | 9761 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 9762 | |
955b61e5 | 9763 | void |
3f5a54e3 SR |
9764 | trace_printk_seq(struct trace_seq *s) |
9765 | { | |
9766 | /* Probably should print a warning here. */ | |
3a161d99 SRRH |
9767 | if (s->seq.len >= TRACE_MAX_PRINT) |
9768 | s->seq.len = TRACE_MAX_PRINT; | |
3f5a54e3 | 9769 | |
820b75f6 SRRH |
9770 | /* |
9771 | * More paranoid code. Although the buffer size is set to | |
9772 | * PAGE_SIZE, and TRACE_MAX_PRINT is 1000, this is just | |
9773 | * an extra layer of protection. | |
9774 | */ | |
9775 | if (WARN_ON_ONCE(s->seq.len >= s->seq.size)) | |
9776 | s->seq.len = s->seq.size - 1; | |
3f5a54e3 SR |
9777 | |
9778 | /* should be zero ended, but we are paranoid. */ | |
3a161d99 | 9779 | s->buffer[s->seq.len] = 0; |
3f5a54e3 SR |
9780 | |
9781 | printk(KERN_TRACE "%s", s->buffer); | |
9782 | ||
f9520750 | 9783 | trace_seq_init(s); |
3f5a54e3 SR |
9784 | } |
9785 | ||
955b61e5 JW |
9786 | void trace_init_global_iter(struct trace_iterator *iter) |
9787 | { | |
9788 | iter->tr = &global_trace; | |
2b6080f2 | 9789 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 9790 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
1c5eb448 | 9791 | iter->array_buffer = &global_trace.array_buffer; |
b2f974d6 CS |
9792 | |
9793 | if (iter->trace && iter->trace->open) | |
9794 | iter->trace->open(iter); | |
9795 | ||
9796 | /* Annotate start of buffers if we had overruns */ | |
1c5eb448 | 9797 | if (ring_buffer_overruns(iter->array_buffer->buffer)) |
b2f974d6 CS |
9798 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
9799 | ||
9800 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ | |
9801 | if (trace_clocks[iter->tr->clock_id].in_ns) | |
9802 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
955b61e5 JW |
9803 | } |
9804 | ||
7fe70b57 | 9805 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 9806 | { |
3f5a54e3 SR |
9807 | /* use static because iter can be a bit big for the stack */ |
9808 | static struct trace_iterator iter; | |
7fe70b57 | 9809 | static atomic_t dump_running; |
983f938a | 9810 | struct trace_array *tr = &global_trace; |
cf586b61 | 9811 | unsigned int old_userobj; |
d769041f SR |
9812 | unsigned long flags; |
9813 | int cnt = 0, cpu; | |
3f5a54e3 | 9814 | |
7fe70b57 SRRH |
9815 | /* Only allow one dump user at a time. */ |
9816 | if (atomic_inc_return(&dump_running) != 1) { | |
9817 | atomic_dec(&dump_running); | |
9818 | return; | |
9819 | } | |
3f5a54e3 | 9820 | |
7fe70b57 SRRH |
9821 | /* |
9822 | * Always turn off tracing when we dump. | |
9823 | * We don't need to show trace output of what happens | |
9824 | * between multiple crashes. | |
9825 | * | |
9826 | * If the user does a sysrq-z, then they can re-enable | |
9827 | * tracing with echo 1 > tracing_on. | |
9828 | */ | |
0ee6b6cf | 9829 | tracing_off(); |
cf586b61 | 9830 | |
7fe70b57 | 9831 | local_irq_save(flags); |
3f5a54e3 | 9832 | |
38dbe0b1 | 9833 | /* Simulate the iterator */ |
955b61e5 | 9834 | trace_init_global_iter(&iter); |
efbbdaa2 | 9835 | /* Can not use kmalloc for iter.temp and iter.fmt */ |
8e99cf91 SRV |
9836 | iter.temp = static_temp_buf; |
9837 | iter.temp_size = STATIC_TEMP_BUF_SIZE; | |
efbbdaa2 MH |
9838 | iter.fmt = static_fmt_buf; |
9839 | iter.fmt_size = STATIC_FMT_BUF_SIZE; | |
955b61e5 | 9840 | |
d769041f | 9841 | for_each_tracing_cpu(cpu) { |
1c5eb448 | 9842 | atomic_inc(&per_cpu_ptr(iter.array_buffer->data, cpu)->disabled); |
d769041f SR |
9843 | } |
9844 | ||
983f938a | 9845 | old_userobj = tr->trace_flags & TRACE_ITER_SYM_USEROBJ; |
cf586b61 | 9846 | |
b54d3de9 | 9847 | /* don't look at user memory in panic mode */ |
983f938a | 9848 | tr->trace_flags &= ~TRACE_ITER_SYM_USEROBJ; |
b54d3de9 | 9849 | |
cecbca96 FW |
9850 | switch (oops_dump_mode) { |
9851 | case DUMP_ALL: | |
ae3b5093 | 9852 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
9853 | break; |
9854 | case DUMP_ORIG: | |
9855 | iter.cpu_file = raw_smp_processor_id(); | |
9856 | break; | |
9857 | case DUMP_NONE: | |
9858 | goto out_enable; | |
9859 | default: | |
9860 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 9861 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
9862 | } |
9863 | ||
9864 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 9865 | |
7fe70b57 SRRH |
9866 | /* Did function tracer already get disabled? */ |
9867 | if (ftrace_is_dead()) { | |
9868 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
9869 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
9870 | } | |
9871 | ||
3f5a54e3 | 9872 | /* |
5c8c206e | 9873 | * We need to stop all tracing on all CPUS to read |
3f5a54e3 SR |
9874 | * the next buffer. This is a bit expensive, but is |
9875 | * not done often. We fill all what we can read, | |
9876 | * and then release the locks again. | |
9877 | */ | |
9878 | ||
3f5a54e3 SR |
9879 | while (!trace_empty(&iter)) { |
9880 | ||
9881 | if (!cnt) | |
9882 | printk(KERN_TRACE "---------------------------------\n"); | |
9883 | ||
9884 | cnt++; | |
9885 | ||
0c97bf86 | 9886 | trace_iterator_reset(&iter); |
3f5a54e3 | 9887 | iter.iter_flags |= TRACE_FILE_LAT_FMT; |
3f5a54e3 | 9888 | |
955b61e5 | 9889 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
9890 | int ret; |
9891 | ||
9892 | ret = print_trace_line(&iter); | |
9893 | if (ret != TRACE_TYPE_NO_CONSUME) | |
9894 | trace_consume(&iter); | |
3f5a54e3 | 9895 | } |
b892e5c8 | 9896 | touch_nmi_watchdog(); |
3f5a54e3 SR |
9897 | |
9898 | trace_printk_seq(&iter.seq); | |
9899 | } | |
9900 | ||
9901 | if (!cnt) | |
9902 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
9903 | else | |
9904 | printk(KERN_TRACE "---------------------------------\n"); | |
9905 | ||
cecbca96 | 9906 | out_enable: |
983f938a | 9907 | tr->trace_flags |= old_userobj; |
cf586b61 | 9908 | |
7fe70b57 | 9909 | for_each_tracing_cpu(cpu) { |
1c5eb448 | 9910 | atomic_dec(&per_cpu_ptr(iter.array_buffer->data, cpu)->disabled); |
cf586b61 | 9911 | } |
03fc7f9c | 9912 | atomic_dec(&dump_running); |
cd891ae0 | 9913 | local_irq_restore(flags); |
3f5a54e3 | 9914 | } |
a8eecf22 | 9915 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 9916 | |
7e465baa TZ |
9917 | #define WRITE_BUFSIZE 4096 |
9918 | ||
9919 | ssize_t trace_parse_run_command(struct file *file, const char __user *buffer, | |
9920 | size_t count, loff_t *ppos, | |
d262271d | 9921 | int (*createfn)(const char *)) |
7e465baa TZ |
9922 | { |
9923 | char *kbuf, *buf, *tmp; | |
9924 | int ret = 0; | |
9925 | size_t done = 0; | |
9926 | size_t size; | |
9927 | ||
9928 | kbuf = kmalloc(WRITE_BUFSIZE, GFP_KERNEL); | |
9929 | if (!kbuf) | |
9930 | return -ENOMEM; | |
9931 | ||
9932 | while (done < count) { | |
9933 | size = count - done; | |
9934 | ||
9935 | if (size >= WRITE_BUFSIZE) | |
9936 | size = WRITE_BUFSIZE - 1; | |
9937 | ||
9938 | if (copy_from_user(kbuf, buffer + done, size)) { | |
9939 | ret = -EFAULT; | |
9940 | goto out; | |
9941 | } | |
9942 | kbuf[size] = '\0'; | |
9943 | buf = kbuf; | |
9944 | do { | |
9945 | tmp = strchr(buf, '\n'); | |
9946 | if (tmp) { | |
9947 | *tmp = '\0'; | |
9948 | size = tmp - buf + 1; | |
9949 | } else { | |
9950 | size = strlen(buf); | |
9951 | if (done + size < count) { | |
9952 | if (buf != kbuf) | |
9953 | break; | |
9954 | /* This can accept WRITE_BUFSIZE - 2 ('\n' + '\0') */ | |
9955 | pr_warn("Line length is too long: Should be less than %d\n", | |
9956 | WRITE_BUFSIZE - 2); | |
9957 | ret = -EINVAL; | |
9958 | goto out; | |
9959 | } | |
9960 | } | |
9961 | done += size; | |
9962 | ||
9963 | /* Remove comments */ | |
9964 | tmp = strchr(buf, '#'); | |
9965 | ||
9966 | if (tmp) | |
9967 | *tmp = '\0'; | |
9968 | ||
d262271d | 9969 | ret = createfn(buf); |
7e465baa TZ |
9970 | if (ret) |
9971 | goto out; | |
9972 | buf += size; | |
9973 | ||
9974 | } while (done < count); | |
9975 | } | |
9976 | ret = done; | |
9977 | ||
9978 | out: | |
9979 | kfree(kbuf); | |
9980 | ||
9981 | return ret; | |
9982 | } | |
9983 | ||
3928a8a2 | 9984 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 9985 | { |
73c5162a | 9986 | int ring_buf_size; |
9e01c1b7 | 9987 | int ret = -ENOMEM; |
4c11d7ae | 9988 | |
a356646a SRV |
9989 | |
9990 | if (security_locked_down(LOCKDOWN_TRACEFS)) { | |
ee195452 | 9991 | pr_warn("Tracing disabled due to lockdown\n"); |
a356646a SRV |
9992 | return -EPERM; |
9993 | } | |
9994 | ||
b5e87c05 | 9995 | /* |
499f7bb0 | 9996 | * Make sure we don't accidentally add more trace options |
b5e87c05 SRRH |
9997 | * than we have bits for. |
9998 | */ | |
9a38a885 | 9999 | BUILD_BUG_ON(TRACE_ITER_LAST_BIT > TRACE_FLAGS_MAX_SIZE); |
b5e87c05 | 10000 | |
9e01c1b7 RR |
10001 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
10002 | goto out; | |
10003 | ||
ccfe9e42 | 10004 | if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) |
9e01c1b7 | 10005 | goto out_free_buffer_mask; |
4c11d7ae | 10006 | |
07d777fe | 10007 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
bf2cbe04 | 10008 | if (&__stop___trace_bprintk_fmt != &__start___trace_bprintk_fmt) |
81698831 | 10009 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
10010 | trace_printk_init_buffers(); |
10011 | ||
73c5162a SR |
10012 | /* To save memory, keep the ring buffer size to its minimum */ |
10013 | if (ring_buffer_expanded) | |
10014 | ring_buf_size = trace_buf_size; | |
10015 | else | |
10016 | ring_buf_size = 1; | |
10017 | ||
9e01c1b7 | 10018 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
ccfe9e42 | 10019 | cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); |
9e01c1b7 | 10020 | |
2b6080f2 SR |
10021 | raw_spin_lock_init(&global_trace.start_lock); |
10022 | ||
b32614c0 SAS |
10023 | /* |
10024 | * The prepare callbacks allocates some memory for the ring buffer. We | |
499f7bb0 | 10025 | * don't free the buffer if the CPU goes down. If we were to free |
b32614c0 SAS |
10026 | * the buffer, then the user would lose any trace that was in the |
10027 | * buffer. The memory will be removed once the "instance" is removed. | |
10028 | */ | |
10029 | ret = cpuhp_setup_state_multi(CPUHP_TRACE_RB_PREPARE, | |
10030 | "trace/RB:preapre", trace_rb_cpu_prepare, | |
10031 | NULL); | |
10032 | if (ret < 0) | |
10033 | goto out_free_cpumask; | |
2c4a33ab | 10034 | /* Used for event triggers */ |
147d88e0 | 10035 | ret = -ENOMEM; |
2c4a33ab SRRH |
10036 | temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); |
10037 | if (!temp_buffer) | |
b32614c0 | 10038 | goto out_rm_hp_state; |
2c4a33ab | 10039 | |
939c7a4f YY |
10040 | if (trace_create_savedcmd() < 0) |
10041 | goto out_free_temp_buffer; | |
10042 | ||
9e01c1b7 | 10043 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 10044 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
24589e3a | 10045 | MEM_FAIL(1, "tracer: failed to allocate ring buffer!\n"); |
939c7a4f | 10046 | goto out_free_savedcmd; |
4c11d7ae | 10047 | } |
a7603ff4 | 10048 | |
499e5470 SR |
10049 | if (global_trace.buffer_disabled) |
10050 | tracing_off(); | |
4c11d7ae | 10051 | |
e1e232ca SR |
10052 | if (trace_boot_clock) { |
10053 | ret = tracing_set_clock(&global_trace, trace_boot_clock); | |
10054 | if (ret < 0) | |
a395d6a7 JP |
10055 | pr_warn("Trace clock %s not defined, going back to default\n", |
10056 | trace_boot_clock); | |
e1e232ca SR |
10057 | } |
10058 | ||
ca164318 SRRH |
10059 | /* |
10060 | * register_tracer() might reference current_trace, so it | |
10061 | * needs to be set before we register anything. This is | |
10062 | * just a bootstrap of current_trace anyway. | |
10063 | */ | |
2b6080f2 SR |
10064 | global_trace.current_trace = &nop_trace; |
10065 | ||
0b9b12c1 SRRH |
10066 | global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
10067 | ||
4104d326 SRRH |
10068 | ftrace_init_global_array_ops(&global_trace); |
10069 | ||
9a38a885 SRRH |
10070 | init_trace_flags_index(&global_trace); |
10071 | ||
ca164318 SRRH |
10072 | register_tracer(&nop_trace); |
10073 | ||
dbeafd0d SRV |
10074 | /* Function tracing may start here (via kernel command line) */ |
10075 | init_function_trace(); | |
10076 | ||
60a11774 SR |
10077 | /* All seems OK, enable tracing */ |
10078 | tracing_disabled = 0; | |
3928a8a2 | 10079 | |
3f5a54e3 SR |
10080 | atomic_notifier_chain_register(&panic_notifier_list, |
10081 | &trace_panic_notifier); | |
10082 | ||
10083 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 10084 | |
ae63b31e SR |
10085 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
10086 | ||
10087 | INIT_LIST_HEAD(&global_trace.systems); | |
10088 | INIT_LIST_HEAD(&global_trace.events); | |
067fe038 | 10089 | INIT_LIST_HEAD(&global_trace.hist_vars); |
2f754e77 | 10090 | INIT_LIST_HEAD(&global_trace.err_log); |
ae63b31e SR |
10091 | list_add(&global_trace.list, &ftrace_trace_arrays); |
10092 | ||
a4d1e688 | 10093 | apply_trace_boot_options(); |
7bcfaf54 | 10094 | |
77fd5c15 SRRH |
10095 | register_snapshot_cmd(); |
10096 | ||
9a6944fe SRV |
10097 | test_can_verify(); |
10098 | ||
2fc1dfbe | 10099 | return 0; |
3f5a54e3 | 10100 | |
939c7a4f YY |
10101 | out_free_savedcmd: |
10102 | free_saved_cmdlines_buffer(savedcmd); | |
2c4a33ab SRRH |
10103 | out_free_temp_buffer: |
10104 | ring_buffer_free(temp_buffer); | |
b32614c0 SAS |
10105 | out_rm_hp_state: |
10106 | cpuhp_remove_multi_state(CPUHP_TRACE_RB_PREPARE); | |
9e01c1b7 | 10107 | out_free_cpumask: |
ccfe9e42 | 10108 | free_cpumask_var(global_trace.tracing_cpumask); |
9e01c1b7 RR |
10109 | out_free_buffer_mask: |
10110 | free_cpumask_var(tracing_buffer_mask); | |
10111 | out: | |
10112 | return ret; | |
bc0c38d1 | 10113 | } |
b2821ae6 | 10114 | |
e725c731 | 10115 | void __init early_trace_init(void) |
5f893b26 | 10116 | { |
0daa2302 SRRH |
10117 | if (tracepoint_printk) { |
10118 | tracepoint_print_iter = | |
0e1e71d3 | 10119 | kzalloc(sizeof(*tracepoint_print_iter), GFP_KERNEL); |
24589e3a SRV |
10120 | if (MEM_FAIL(!tracepoint_print_iter, |
10121 | "Failed to allocate trace iterator\n")) | |
0daa2302 | 10122 | tracepoint_printk = 0; |
42391745 SRRH |
10123 | else |
10124 | static_key_enable(&tracepoint_printk_key.key); | |
0daa2302 | 10125 | } |
5f893b26 | 10126 | tracer_alloc_buffers(); |
e725c731 SRV |
10127 | } |
10128 | ||
10129 | void __init trace_init(void) | |
10130 | { | |
0c564a53 | 10131 | trace_event_init(); |
5f893b26 SRRH |
10132 | } |
10133 | ||
f3860136 | 10134 | __init static void clear_boot_tracer(void) |
b2821ae6 SR |
10135 | { |
10136 | /* | |
10137 | * The default tracer at boot buffer is an init section. | |
10138 | * This function is called in lateinit. If we did not | |
10139 | * find the boot tracer, then clear it out, to prevent | |
10140 | * later registration from accessing the buffer that is | |
10141 | * about to be freed. | |
10142 | */ | |
10143 | if (!default_bootup_tracer) | |
f3860136 | 10144 | return; |
b2821ae6 SR |
10145 | |
10146 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
10147 | default_bootup_tracer); | |
10148 | default_bootup_tracer = NULL; | |
b2821ae6 SR |
10149 | } |
10150 | ||
3fd49c9e | 10151 | #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK |
f3860136 | 10152 | __init static void tracing_set_default_clock(void) |
3fd49c9e CW |
10153 | { |
10154 | /* sched_clock_stable() is determined in late_initcall */ | |
5125eee4 | 10155 | if (!trace_boot_clock && !sched_clock_stable()) { |
bf24daac MI |
10156 | if (security_locked_down(LOCKDOWN_TRACEFS)) { |
10157 | pr_warn("Can not set tracing clock due to lockdown\n"); | |
f3860136 | 10158 | return; |
bf24daac MI |
10159 | } |
10160 | ||
3fd49c9e CW |
10161 | printk(KERN_WARNING |
10162 | "Unstable clock detected, switching default tracing clock to \"global\"\n" | |
10163 | "If you want to keep using the local clock, then add:\n" | |
10164 | " \"trace_clock=local\"\n" | |
10165 | "on the kernel command line\n"); | |
10166 | tracing_set_clock(&global_trace, "global"); | |
10167 | } | |
f3860136 SRV |
10168 | } |
10169 | #else | |
10170 | static inline void tracing_set_default_clock(void) { } | |
10171 | #endif | |
3fd49c9e | 10172 | |
f3860136 SRV |
10173 | __init static int late_trace_init(void) |
10174 | { | |
10175 | if (tracepoint_printk && tracepoint_printk_stop_on_boot) { | |
10176 | static_key_disable(&tracepoint_printk_key.key); | |
10177 | tracepoint_printk = 0; | |
10178 | } | |
3fd49c9e | 10179 | |
f3860136 SRV |
10180 | tracing_set_default_clock(); |
10181 | clear_boot_tracer(); | |
3fd49c9e CW |
10182 | return 0; |
10183 | } | |
f3860136 SRV |
10184 | |
10185 | late_initcall_sync(late_trace_init); |