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Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
2b6080f2 | 4 | * Copyright (C) 2007-2012 Steven Rostedt <srostedt@redhat.com> |
bc0c38d1 SR |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
6d49e352 | 12 | * Copyright (C) 2004 Nadia Yvette Chambers |
bc0c38d1 | 13 | */ |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
273b281f | 15 | #include <generated/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
8434dc93 | 23 | #include <linux/tracefs.h> |
4c11d7ae | 24 | #include <linux/pagemap.h> |
bc0c38d1 SR |
25 | #include <linux/hardirq.h> |
26 | #include <linux/linkage.h> | |
27 | #include <linux/uaccess.h> | |
2cadf913 | 28 | #include <linux/kprobes.h> |
bc0c38d1 SR |
29 | #include <linux/ftrace.h> |
30 | #include <linux/module.h> | |
31 | #include <linux/percpu.h> | |
2cadf913 | 32 | #include <linux/splice.h> |
3f5a54e3 | 33 | #include <linux/kdebug.h> |
5f0c6c03 | 34 | #include <linux/string.h> |
f76180bc | 35 | #include <linux/mount.h> |
7e53bd42 | 36 | #include <linux/rwsem.h> |
5a0e3ad6 | 37 | #include <linux/slab.h> |
bc0c38d1 SR |
38 | #include <linux/ctype.h> |
39 | #include <linux/init.h> | |
2a2cc8f7 | 40 | #include <linux/poll.h> |
b892e5c8 | 41 | #include <linux/nmi.h> |
bc0c38d1 | 42 | #include <linux/fs.h> |
8bd75c77 | 43 | #include <linux/sched/rt.h> |
86387f7e | 44 | |
bc0c38d1 | 45 | #include "trace.h" |
f0868d1e | 46 | #include "trace_output.h" |
bc0c38d1 | 47 | |
73c5162a SR |
48 | /* |
49 | * On boot up, the ring buffer is set to the minimum size, so that | |
50 | * we do not waste memory on systems that are not using tracing. | |
51 | */ | |
55034cd6 | 52 | bool ring_buffer_expanded; |
73c5162a | 53 | |
8e1b82e0 FW |
54 | /* |
55 | * We need to change this state when a selftest is running. | |
ff32504f FW |
56 | * A selftest will lurk into the ring-buffer to count the |
57 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 58 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
59 | * at the same time, giving false positive or negative results. |
60 | */ | |
8e1b82e0 | 61 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 62 | |
b2821ae6 SR |
63 | /* |
64 | * If a tracer is running, we do not want to run SELFTEST. | |
65 | */ | |
020e5f85 | 66 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 67 | |
0daa2302 SRRH |
68 | /* Pipe tracepoints to printk */ |
69 | struct trace_iterator *tracepoint_print_iter; | |
70 | int tracepoint_printk; | |
71 | ||
adf9f195 FW |
72 | /* For tracers that don't implement custom flags */ |
73 | static struct tracer_opt dummy_tracer_opt[] = { | |
74 | { } | |
75 | }; | |
76 | ||
77 | static struct tracer_flags dummy_tracer_flags = { | |
78 | .val = 0, | |
79 | .opts = dummy_tracer_opt | |
80 | }; | |
81 | ||
8c1a49ae SRRH |
82 | static int |
83 | dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) | |
adf9f195 FW |
84 | { |
85 | return 0; | |
86 | } | |
0f048701 | 87 | |
7ffbd48d SR |
88 | /* |
89 | * To prevent the comm cache from being overwritten when no | |
90 | * tracing is active, only save the comm when a trace event | |
91 | * occurred. | |
92 | */ | |
93 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
94 | ||
0f048701 SR |
95 | /* |
96 | * Kill all tracing for good (never come back). | |
97 | * It is initialized to 1 but will turn to zero if the initialization | |
98 | * of the tracer is successful. But that is the only place that sets | |
99 | * this back to zero. | |
100 | */ | |
4fd27358 | 101 | static int tracing_disabled = 1; |
0f048701 | 102 | |
9288f99a | 103 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 104 | |
955b61e5 | 105 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 106 | |
944ac425 SR |
107 | /* |
108 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
109 | * | |
110 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
111 | * is set, then ftrace_dump is called. This will output the contents | |
112 | * of the ftrace buffers to the console. This is very useful for | |
113 | * capturing traces that lead to crashes and outputing it to a | |
114 | * serial console. | |
115 | * | |
116 | * It is default off, but you can enable it with either specifying | |
117 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
118 | * /proc/sys/kernel/ftrace_dump_on_oops |
119 | * Set 1 if you want to dump buffers of all CPUs | |
120 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 121 | */ |
cecbca96 FW |
122 | |
123 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 124 | |
de7edd31 SRRH |
125 | /* When set, tracing will stop when a WARN*() is hit */ |
126 | int __disable_trace_on_warning; | |
127 | ||
9828413d SRRH |
128 | #ifdef CONFIG_TRACE_ENUM_MAP_FILE |
129 | /* Map of enums to their values, for "enum_map" file */ | |
130 | struct trace_enum_map_head { | |
131 | struct module *mod; | |
132 | unsigned long length; | |
133 | }; | |
134 | ||
135 | union trace_enum_map_item; | |
136 | ||
137 | struct trace_enum_map_tail { | |
138 | /* | |
139 | * "end" is first and points to NULL as it must be different | |
140 | * than "mod" or "enum_string" | |
141 | */ | |
142 | union trace_enum_map_item *next; | |
143 | const char *end; /* points to NULL */ | |
144 | }; | |
145 | ||
146 | static DEFINE_MUTEX(trace_enum_mutex); | |
147 | ||
148 | /* | |
149 | * The trace_enum_maps are saved in an array with two extra elements, | |
150 | * one at the beginning, and one at the end. The beginning item contains | |
151 | * the count of the saved maps (head.length), and the module they | |
152 | * belong to if not built in (head.mod). The ending item contains a | |
153 | * pointer to the next array of saved enum_map items. | |
154 | */ | |
155 | union trace_enum_map_item { | |
156 | struct trace_enum_map map; | |
157 | struct trace_enum_map_head head; | |
158 | struct trace_enum_map_tail tail; | |
159 | }; | |
160 | ||
161 | static union trace_enum_map_item *trace_enum_maps; | |
162 | #endif /* CONFIG_TRACE_ENUM_MAP_FILE */ | |
163 | ||
607e2ea1 | 164 | static int tracing_set_tracer(struct trace_array *tr, const char *buf); |
b2821ae6 | 165 | |
ee6c2c1b LZ |
166 | #define MAX_TRACER_SIZE 100 |
167 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 168 | static char *default_bootup_tracer; |
d9e54076 | 169 | |
55034cd6 SRRH |
170 | static bool allocate_snapshot; |
171 | ||
1beee96b | 172 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 173 | { |
67012ab1 | 174 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 175 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 176 | /* We are using ftrace early, expand it */ |
55034cd6 | 177 | ring_buffer_expanded = true; |
d9e54076 PZ |
178 | return 1; |
179 | } | |
1beee96b | 180 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 181 | |
944ac425 SR |
182 | static int __init set_ftrace_dump_on_oops(char *str) |
183 | { | |
cecbca96 FW |
184 | if (*str++ != '=' || !*str) { |
185 | ftrace_dump_on_oops = DUMP_ALL; | |
186 | return 1; | |
187 | } | |
188 | ||
189 | if (!strcmp("orig_cpu", str)) { | |
190 | ftrace_dump_on_oops = DUMP_ORIG; | |
191 | return 1; | |
192 | } | |
193 | ||
194 | return 0; | |
944ac425 SR |
195 | } |
196 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 197 | |
de7edd31 SRRH |
198 | static int __init stop_trace_on_warning(char *str) |
199 | { | |
933ff9f2 LCG |
200 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) |
201 | __disable_trace_on_warning = 1; | |
de7edd31 SRRH |
202 | return 1; |
203 | } | |
933ff9f2 | 204 | __setup("traceoff_on_warning", stop_trace_on_warning); |
de7edd31 | 205 | |
3209cff4 | 206 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
207 | { |
208 | allocate_snapshot = true; | |
209 | /* We also need the main ring buffer expanded */ | |
210 | ring_buffer_expanded = true; | |
211 | return 1; | |
212 | } | |
3209cff4 | 213 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 214 | |
7bcfaf54 SR |
215 | |
216 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
217 | static char *trace_boot_options __initdata; | |
218 | ||
219 | static int __init set_trace_boot_options(char *str) | |
220 | { | |
67012ab1 | 221 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
222 | trace_boot_options = trace_boot_options_buf; |
223 | return 0; | |
224 | } | |
225 | __setup("trace_options=", set_trace_boot_options); | |
226 | ||
e1e232ca SR |
227 | static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; |
228 | static char *trace_boot_clock __initdata; | |
229 | ||
230 | static int __init set_trace_boot_clock(char *str) | |
231 | { | |
232 | strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); | |
233 | trace_boot_clock = trace_boot_clock_buf; | |
234 | return 0; | |
235 | } | |
236 | __setup("trace_clock=", set_trace_boot_clock); | |
237 | ||
0daa2302 SRRH |
238 | static int __init set_tracepoint_printk(char *str) |
239 | { | |
240 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) | |
241 | tracepoint_printk = 1; | |
242 | return 1; | |
243 | } | |
244 | __setup("tp_printk", set_tracepoint_printk); | |
de7edd31 | 245 | |
cf8e3474 | 246 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
247 | { |
248 | nsec += 500; | |
249 | do_div(nsec, 1000); | |
250 | return nsec; | |
251 | } | |
252 | ||
4fcdae83 SR |
253 | /* |
254 | * The global_trace is the descriptor that holds the tracing | |
255 | * buffers for the live tracing. For each CPU, it contains | |
256 | * a link list of pages that will store trace entries. The | |
257 | * page descriptor of the pages in the memory is used to hold | |
258 | * the link list by linking the lru item in the page descriptor | |
259 | * to each of the pages in the buffer per CPU. | |
260 | * | |
261 | * For each active CPU there is a data field that holds the | |
262 | * pages for the buffer for that CPU. Each CPU has the same number | |
263 | * of pages allocated for its buffer. | |
264 | */ | |
bc0c38d1 SR |
265 | static struct trace_array global_trace; |
266 | ||
ae63b31e | 267 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 268 | |
ff451961 SRRH |
269 | int trace_array_get(struct trace_array *this_tr) |
270 | { | |
271 | struct trace_array *tr; | |
272 | int ret = -ENODEV; | |
273 | ||
274 | mutex_lock(&trace_types_lock); | |
275 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
276 | if (tr == this_tr) { | |
277 | tr->ref++; | |
278 | ret = 0; | |
279 | break; | |
280 | } | |
281 | } | |
282 | mutex_unlock(&trace_types_lock); | |
283 | ||
284 | return ret; | |
285 | } | |
286 | ||
287 | static void __trace_array_put(struct trace_array *this_tr) | |
288 | { | |
289 | WARN_ON(!this_tr->ref); | |
290 | this_tr->ref--; | |
291 | } | |
292 | ||
293 | void trace_array_put(struct trace_array *this_tr) | |
294 | { | |
295 | mutex_lock(&trace_types_lock); | |
296 | __trace_array_put(this_tr); | |
297 | mutex_unlock(&trace_types_lock); | |
298 | } | |
299 | ||
7f1d2f82 | 300 | int filter_check_discard(struct trace_event_file *file, void *rec, |
f306cc82 TZ |
301 | struct ring_buffer *buffer, |
302 | struct ring_buffer_event *event) | |
eb02ce01 | 303 | { |
5d6ad960 | 304 | if (unlikely(file->flags & EVENT_FILE_FL_FILTERED) && |
f306cc82 TZ |
305 | !filter_match_preds(file->filter, rec)) { |
306 | ring_buffer_discard_commit(buffer, event); | |
307 | return 1; | |
308 | } | |
309 | ||
310 | return 0; | |
311 | } | |
312 | EXPORT_SYMBOL_GPL(filter_check_discard); | |
313 | ||
2425bcb9 | 314 | int call_filter_check_discard(struct trace_event_call *call, void *rec, |
f306cc82 TZ |
315 | struct ring_buffer *buffer, |
316 | struct ring_buffer_event *event) | |
317 | { | |
318 | if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && | |
319 | !filter_match_preds(call->filter, rec)) { | |
320 | ring_buffer_discard_commit(buffer, event); | |
321 | return 1; | |
322 | } | |
323 | ||
324 | return 0; | |
eb02ce01 | 325 | } |
f306cc82 | 326 | EXPORT_SYMBOL_GPL(call_filter_check_discard); |
eb02ce01 | 327 | |
ad1438a0 | 328 | static cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) |
37886f6a SR |
329 | { |
330 | u64 ts; | |
331 | ||
332 | /* Early boot up does not have a buffer yet */ | |
9457158b | 333 | if (!buf->buffer) |
37886f6a SR |
334 | return trace_clock_local(); |
335 | ||
9457158b AL |
336 | ts = ring_buffer_time_stamp(buf->buffer, cpu); |
337 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); | |
37886f6a SR |
338 | |
339 | return ts; | |
340 | } | |
bc0c38d1 | 341 | |
9457158b AL |
342 | cycle_t ftrace_now(int cpu) |
343 | { | |
344 | return buffer_ftrace_now(&global_trace.trace_buffer, cpu); | |
345 | } | |
346 | ||
10246fa3 SRRH |
347 | /** |
348 | * tracing_is_enabled - Show if global_trace has been disabled | |
349 | * | |
350 | * Shows if the global trace has been enabled or not. It uses the | |
351 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
352 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
353 | * need to know the accurate state, use tracing_is_on() which is a little | |
354 | * slower, but accurate. | |
355 | */ | |
9036990d SR |
356 | int tracing_is_enabled(void) |
357 | { | |
10246fa3 SRRH |
358 | /* |
359 | * For quick access (irqsoff uses this in fast path), just | |
360 | * return the mirror variable of the state of the ring buffer. | |
361 | * It's a little racy, but we don't really care. | |
362 | */ | |
363 | smp_rmb(); | |
364 | return !global_trace.buffer_disabled; | |
9036990d SR |
365 | } |
366 | ||
4fcdae83 | 367 | /* |
3928a8a2 SR |
368 | * trace_buf_size is the size in bytes that is allocated |
369 | * for a buffer. Note, the number of bytes is always rounded | |
370 | * to page size. | |
3f5a54e3 SR |
371 | * |
372 | * This number is purposely set to a low number of 16384. | |
373 | * If the dump on oops happens, it will be much appreciated | |
374 | * to not have to wait for all that output. Anyway this can be | |
375 | * boot time and run time configurable. | |
4fcdae83 | 376 | */ |
3928a8a2 | 377 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 378 | |
3928a8a2 | 379 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 380 | |
4fcdae83 | 381 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 382 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 383 | |
4fcdae83 SR |
384 | /* |
385 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 386 | */ |
a8227415 | 387 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 388 | |
7e53bd42 LJ |
389 | /* |
390 | * serialize the access of the ring buffer | |
391 | * | |
392 | * ring buffer serializes readers, but it is low level protection. | |
393 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
394 | * are not protected by ring buffer. | |
395 | * | |
396 | * The content of events may become garbage if we allow other process consumes | |
397 | * these events concurrently: | |
398 | * A) the page of the consumed events may become a normal page | |
399 | * (not reader page) in ring buffer, and this page will be rewrited | |
400 | * by events producer. | |
401 | * B) The page of the consumed events may become a page for splice_read, | |
402 | * and this page will be returned to system. | |
403 | * | |
404 | * These primitives allow multi process access to different cpu ring buffer | |
405 | * concurrently. | |
406 | * | |
407 | * These primitives don't distinguish read-only and read-consume access. | |
408 | * Multi read-only access are also serialized. | |
409 | */ | |
410 | ||
411 | #ifdef CONFIG_SMP | |
412 | static DECLARE_RWSEM(all_cpu_access_lock); | |
413 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
414 | ||
415 | static inline void trace_access_lock(int cpu) | |
416 | { | |
ae3b5093 | 417 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
418 | /* gain it for accessing the whole ring buffer. */ |
419 | down_write(&all_cpu_access_lock); | |
420 | } else { | |
421 | /* gain it for accessing a cpu ring buffer. */ | |
422 | ||
ae3b5093 | 423 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
424 | down_read(&all_cpu_access_lock); |
425 | ||
426 | /* Secondly block other access to this @cpu ring buffer. */ | |
427 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
428 | } | |
429 | } | |
430 | ||
431 | static inline void trace_access_unlock(int cpu) | |
432 | { | |
ae3b5093 | 433 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
434 | up_write(&all_cpu_access_lock); |
435 | } else { | |
436 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
437 | up_read(&all_cpu_access_lock); | |
438 | } | |
439 | } | |
440 | ||
441 | static inline void trace_access_lock_init(void) | |
442 | { | |
443 | int cpu; | |
444 | ||
445 | for_each_possible_cpu(cpu) | |
446 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
447 | } | |
448 | ||
449 | #else | |
450 | ||
451 | static DEFINE_MUTEX(access_lock); | |
452 | ||
453 | static inline void trace_access_lock(int cpu) | |
454 | { | |
455 | (void)cpu; | |
456 | mutex_lock(&access_lock); | |
457 | } | |
458 | ||
459 | static inline void trace_access_unlock(int cpu) | |
460 | { | |
461 | (void)cpu; | |
462 | mutex_unlock(&access_lock); | |
463 | } | |
464 | ||
465 | static inline void trace_access_lock_init(void) | |
466 | { | |
467 | } | |
468 | ||
469 | #endif | |
470 | ||
ee6bce52 | 471 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 472 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 473 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 | 474 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
328df475 | 475 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION; |
e7e2ee89 | 476 | |
5280bcef | 477 | static void tracer_tracing_on(struct trace_array *tr) |
10246fa3 SRRH |
478 | { |
479 | if (tr->trace_buffer.buffer) | |
480 | ring_buffer_record_on(tr->trace_buffer.buffer); | |
481 | /* | |
482 | * This flag is looked at when buffers haven't been allocated | |
483 | * yet, or by some tracers (like irqsoff), that just want to | |
484 | * know if the ring buffer has been disabled, but it can handle | |
485 | * races of where it gets disabled but we still do a record. | |
486 | * As the check is in the fast path of the tracers, it is more | |
487 | * important to be fast than accurate. | |
488 | */ | |
489 | tr->buffer_disabled = 0; | |
490 | /* Make the flag seen by readers */ | |
491 | smp_wmb(); | |
492 | } | |
493 | ||
499e5470 SR |
494 | /** |
495 | * tracing_on - enable tracing buffers | |
496 | * | |
497 | * This function enables tracing buffers that may have been | |
498 | * disabled with tracing_off. | |
499 | */ | |
500 | void tracing_on(void) | |
501 | { | |
10246fa3 | 502 | tracer_tracing_on(&global_trace); |
499e5470 SR |
503 | } |
504 | EXPORT_SYMBOL_GPL(tracing_on); | |
505 | ||
09ae7234 SRRH |
506 | /** |
507 | * __trace_puts - write a constant string into the trace buffer. | |
508 | * @ip: The address of the caller | |
509 | * @str: The constant string to write | |
510 | * @size: The size of the string. | |
511 | */ | |
512 | int __trace_puts(unsigned long ip, const char *str, int size) | |
513 | { | |
514 | struct ring_buffer_event *event; | |
515 | struct ring_buffer *buffer; | |
516 | struct print_entry *entry; | |
517 | unsigned long irq_flags; | |
518 | int alloc; | |
8abfb872 J |
519 | int pc; |
520 | ||
f0160a5a J |
521 | if (!(trace_flags & TRACE_ITER_PRINTK)) |
522 | return 0; | |
523 | ||
8abfb872 | 524 | pc = preempt_count(); |
09ae7234 | 525 | |
3132e107 SRRH |
526 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
527 | return 0; | |
528 | ||
09ae7234 SRRH |
529 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ |
530 | ||
531 | local_save_flags(irq_flags); | |
532 | buffer = global_trace.trace_buffer.buffer; | |
533 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, | |
8abfb872 | 534 | irq_flags, pc); |
09ae7234 SRRH |
535 | if (!event) |
536 | return 0; | |
537 | ||
538 | entry = ring_buffer_event_data(event); | |
539 | entry->ip = ip; | |
540 | ||
541 | memcpy(&entry->buf, str, size); | |
542 | ||
543 | /* Add a newline if necessary */ | |
544 | if (entry->buf[size - 1] != '\n') { | |
545 | entry->buf[size] = '\n'; | |
546 | entry->buf[size + 1] = '\0'; | |
547 | } else | |
548 | entry->buf[size] = '\0'; | |
549 | ||
550 | __buffer_unlock_commit(buffer, event); | |
8abfb872 | 551 | ftrace_trace_stack(buffer, irq_flags, 4, pc); |
09ae7234 SRRH |
552 | |
553 | return size; | |
554 | } | |
555 | EXPORT_SYMBOL_GPL(__trace_puts); | |
556 | ||
557 | /** | |
558 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
559 | * @ip: The address of the caller | |
560 | * @str: The constant string to write to the buffer to | |
561 | */ | |
562 | int __trace_bputs(unsigned long ip, const char *str) | |
563 | { | |
564 | struct ring_buffer_event *event; | |
565 | struct ring_buffer *buffer; | |
566 | struct bputs_entry *entry; | |
567 | unsigned long irq_flags; | |
568 | int size = sizeof(struct bputs_entry); | |
8abfb872 J |
569 | int pc; |
570 | ||
f0160a5a J |
571 | if (!(trace_flags & TRACE_ITER_PRINTK)) |
572 | return 0; | |
573 | ||
8abfb872 | 574 | pc = preempt_count(); |
09ae7234 | 575 | |
3132e107 SRRH |
576 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
577 | return 0; | |
578 | ||
09ae7234 SRRH |
579 | local_save_flags(irq_flags); |
580 | buffer = global_trace.trace_buffer.buffer; | |
581 | event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, | |
8abfb872 | 582 | irq_flags, pc); |
09ae7234 SRRH |
583 | if (!event) |
584 | return 0; | |
585 | ||
586 | entry = ring_buffer_event_data(event); | |
587 | entry->ip = ip; | |
588 | entry->str = str; | |
589 | ||
590 | __buffer_unlock_commit(buffer, event); | |
8abfb872 | 591 | ftrace_trace_stack(buffer, irq_flags, 4, pc); |
09ae7234 SRRH |
592 | |
593 | return 1; | |
594 | } | |
595 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
596 | ||
ad909e21 SRRH |
597 | #ifdef CONFIG_TRACER_SNAPSHOT |
598 | /** | |
599 | * trace_snapshot - take a snapshot of the current buffer. | |
600 | * | |
601 | * This causes a swap between the snapshot buffer and the current live | |
602 | * tracing buffer. You can use this to take snapshots of the live | |
603 | * trace when some condition is triggered, but continue to trace. | |
604 | * | |
605 | * Note, make sure to allocate the snapshot with either | |
606 | * a tracing_snapshot_alloc(), or by doing it manually | |
607 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
608 | * | |
609 | * If the snapshot buffer is not allocated, it will stop tracing. | |
610 | * Basically making a permanent snapshot. | |
611 | */ | |
612 | void tracing_snapshot(void) | |
613 | { | |
614 | struct trace_array *tr = &global_trace; | |
615 | struct tracer *tracer = tr->current_trace; | |
616 | unsigned long flags; | |
617 | ||
1b22e382 SRRH |
618 | if (in_nmi()) { |
619 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
620 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
621 | return; | |
622 | } | |
623 | ||
ad909e21 | 624 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
625 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
626 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
627 | tracing_off(); |
628 | return; | |
629 | } | |
630 | ||
631 | /* Note, snapshot can not be used when the tracer uses it */ | |
632 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
633 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
634 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
635 | return; |
636 | } | |
637 | ||
638 | local_irq_save(flags); | |
639 | update_max_tr(tr, current, smp_processor_id()); | |
640 | local_irq_restore(flags); | |
641 | } | |
1b22e382 | 642 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
643 | |
644 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
645 | struct trace_buffer *size_buf, int cpu_id); | |
3209cff4 SRRH |
646 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); |
647 | ||
648 | static int alloc_snapshot(struct trace_array *tr) | |
649 | { | |
650 | int ret; | |
651 | ||
652 | if (!tr->allocated_snapshot) { | |
653 | ||
654 | /* allocate spare buffer */ | |
655 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
656 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
657 | if (ret < 0) | |
658 | return ret; | |
659 | ||
660 | tr->allocated_snapshot = true; | |
661 | } | |
662 | ||
663 | return 0; | |
664 | } | |
665 | ||
ad1438a0 | 666 | static void free_snapshot(struct trace_array *tr) |
3209cff4 SRRH |
667 | { |
668 | /* | |
669 | * We don't free the ring buffer. instead, resize it because | |
670 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
671 | * we want preserve it. | |
672 | */ | |
673 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
674 | set_buffer_entries(&tr->max_buffer, 1); | |
675 | tracing_reset_online_cpus(&tr->max_buffer); | |
676 | tr->allocated_snapshot = false; | |
677 | } | |
ad909e21 | 678 | |
93e31ffb TZ |
679 | /** |
680 | * tracing_alloc_snapshot - allocate snapshot buffer. | |
681 | * | |
682 | * This only allocates the snapshot buffer if it isn't already | |
683 | * allocated - it doesn't also take a snapshot. | |
684 | * | |
685 | * This is meant to be used in cases where the snapshot buffer needs | |
686 | * to be set up for events that can't sleep but need to be able to | |
687 | * trigger a snapshot. | |
688 | */ | |
689 | int tracing_alloc_snapshot(void) | |
690 | { | |
691 | struct trace_array *tr = &global_trace; | |
692 | int ret; | |
693 | ||
694 | ret = alloc_snapshot(tr); | |
695 | WARN_ON(ret < 0); | |
696 | ||
697 | return ret; | |
698 | } | |
699 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
700 | ||
ad909e21 SRRH |
701 | /** |
702 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
703 | * | |
704 | * This is similar to trace_snapshot(), but it will allocate the | |
705 | * snapshot buffer if it isn't already allocated. Use this only | |
706 | * where it is safe to sleep, as the allocation may sleep. | |
707 | * | |
708 | * This causes a swap between the snapshot buffer and the current live | |
709 | * tracing buffer. You can use this to take snapshots of the live | |
710 | * trace when some condition is triggered, but continue to trace. | |
711 | */ | |
712 | void tracing_snapshot_alloc(void) | |
713 | { | |
ad909e21 SRRH |
714 | int ret; |
715 | ||
93e31ffb TZ |
716 | ret = tracing_alloc_snapshot(); |
717 | if (ret < 0) | |
3209cff4 | 718 | return; |
ad909e21 SRRH |
719 | |
720 | tracing_snapshot(); | |
721 | } | |
1b22e382 | 722 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
723 | #else |
724 | void tracing_snapshot(void) | |
725 | { | |
726 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
727 | } | |
1b22e382 | 728 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
93e31ffb TZ |
729 | int tracing_alloc_snapshot(void) |
730 | { | |
731 | WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); | |
732 | return -ENODEV; | |
733 | } | |
734 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
ad909e21 SRRH |
735 | void tracing_snapshot_alloc(void) |
736 | { | |
737 | /* Give warning */ | |
738 | tracing_snapshot(); | |
739 | } | |
1b22e382 | 740 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
741 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
742 | ||
5280bcef | 743 | static void tracer_tracing_off(struct trace_array *tr) |
10246fa3 SRRH |
744 | { |
745 | if (tr->trace_buffer.buffer) | |
746 | ring_buffer_record_off(tr->trace_buffer.buffer); | |
747 | /* | |
748 | * This flag is looked at when buffers haven't been allocated | |
749 | * yet, or by some tracers (like irqsoff), that just want to | |
750 | * know if the ring buffer has been disabled, but it can handle | |
751 | * races of where it gets disabled but we still do a record. | |
752 | * As the check is in the fast path of the tracers, it is more | |
753 | * important to be fast than accurate. | |
754 | */ | |
755 | tr->buffer_disabled = 1; | |
756 | /* Make the flag seen by readers */ | |
757 | smp_wmb(); | |
758 | } | |
759 | ||
499e5470 SR |
760 | /** |
761 | * tracing_off - turn off tracing buffers | |
762 | * | |
763 | * This function stops the tracing buffers from recording data. | |
764 | * It does not disable any overhead the tracers themselves may | |
765 | * be causing. This function simply causes all recording to | |
766 | * the ring buffers to fail. | |
767 | */ | |
768 | void tracing_off(void) | |
769 | { | |
10246fa3 | 770 | tracer_tracing_off(&global_trace); |
499e5470 SR |
771 | } |
772 | EXPORT_SYMBOL_GPL(tracing_off); | |
773 | ||
de7edd31 SRRH |
774 | void disable_trace_on_warning(void) |
775 | { | |
776 | if (__disable_trace_on_warning) | |
777 | tracing_off(); | |
778 | } | |
779 | ||
10246fa3 SRRH |
780 | /** |
781 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
782 | * @tr : the trace array to know if ring buffer is enabled | |
783 | * | |
784 | * Shows real state of the ring buffer if it is enabled or not. | |
785 | */ | |
5280bcef | 786 | static int tracer_tracing_is_on(struct trace_array *tr) |
10246fa3 SRRH |
787 | { |
788 | if (tr->trace_buffer.buffer) | |
789 | return ring_buffer_record_is_on(tr->trace_buffer.buffer); | |
790 | return !tr->buffer_disabled; | |
791 | } | |
792 | ||
499e5470 SR |
793 | /** |
794 | * tracing_is_on - show state of ring buffers enabled | |
795 | */ | |
796 | int tracing_is_on(void) | |
797 | { | |
10246fa3 | 798 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
799 | } |
800 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
801 | ||
3928a8a2 | 802 | static int __init set_buf_size(char *str) |
bc0c38d1 | 803 | { |
3928a8a2 | 804 | unsigned long buf_size; |
c6caeeb1 | 805 | |
bc0c38d1 SR |
806 | if (!str) |
807 | return 0; | |
9d612bef | 808 | buf_size = memparse(str, &str); |
c6caeeb1 | 809 | /* nr_entries can not be zero */ |
9d612bef | 810 | if (buf_size == 0) |
c6caeeb1 | 811 | return 0; |
3928a8a2 | 812 | trace_buf_size = buf_size; |
bc0c38d1 SR |
813 | return 1; |
814 | } | |
3928a8a2 | 815 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 816 | |
0e950173 TB |
817 | static int __init set_tracing_thresh(char *str) |
818 | { | |
87abb3b1 | 819 | unsigned long threshold; |
0e950173 TB |
820 | int ret; |
821 | ||
822 | if (!str) | |
823 | return 0; | |
bcd83ea6 | 824 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
825 | if (ret < 0) |
826 | return 0; | |
87abb3b1 | 827 | tracing_thresh = threshold * 1000; |
0e950173 TB |
828 | return 1; |
829 | } | |
830 | __setup("tracing_thresh=", set_tracing_thresh); | |
831 | ||
57f50be1 SR |
832 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
833 | { | |
834 | return nsecs / 1000; | |
835 | } | |
836 | ||
4fcdae83 | 837 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
838 | static const char *trace_options[] = { |
839 | "print-parent", | |
840 | "sym-offset", | |
841 | "sym-addr", | |
842 | "verbose", | |
f9896bf3 | 843 | "raw", |
5e3ca0ec | 844 | "hex", |
cb0f12aa | 845 | "bin", |
2a2cc8f7 | 846 | "block", |
86387f7e | 847 | "stacktrace", |
5e1607a0 | 848 | "trace_printk", |
b2a866f9 | 849 | "ftrace_preempt", |
9f029e83 | 850 | "branch", |
12ef7d44 | 851 | "annotate", |
02b67518 | 852 | "userstacktrace", |
b54d3de9 | 853 | "sym-userobj", |
66896a85 | 854 | "printk-msg-only", |
c4a8e8be | 855 | "context-info", |
c032ef64 | 856 | "latency-format", |
be6f164a | 857 | "sleep-time", |
a2a16d6a | 858 | "graph-time", |
e870e9a1 | 859 | "record-cmd", |
750912fa | 860 | "overwrite", |
cf30cf67 | 861 | "disable_on_free", |
77271ce4 | 862 | "irq-info", |
5224c3a3 | 863 | "markers", |
328df475 | 864 | "function-trace", |
bc0c38d1 SR |
865 | NULL |
866 | }; | |
867 | ||
5079f326 Z |
868 | static struct { |
869 | u64 (*func)(void); | |
870 | const char *name; | |
8be0709f | 871 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 872 | } trace_clocks[] = { |
1b3e5c09 TG |
873 | { trace_clock_local, "local", 1 }, |
874 | { trace_clock_global, "global", 1 }, | |
875 | { trace_clock_counter, "counter", 0 }, | |
e7fda6c4 | 876 | { trace_clock_jiffies, "uptime", 0 }, |
1b3e5c09 TG |
877 | { trace_clock, "perf", 1 }, |
878 | { ktime_get_mono_fast_ns, "mono", 1 }, | |
aabfa5f2 | 879 | { ktime_get_raw_fast_ns, "mono_raw", 1 }, |
8cbd9cc6 | 880 | ARCH_TRACE_CLOCKS |
5079f326 Z |
881 | }; |
882 | ||
b63f39ea | 883 | /* |
884 | * trace_parser_get_init - gets the buffer for trace parser | |
885 | */ | |
886 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
887 | { | |
888 | memset(parser, 0, sizeof(*parser)); | |
889 | ||
890 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
891 | if (!parser->buffer) | |
892 | return 1; | |
893 | ||
894 | parser->size = size; | |
895 | return 0; | |
896 | } | |
897 | ||
898 | /* | |
899 | * trace_parser_put - frees the buffer for trace parser | |
900 | */ | |
901 | void trace_parser_put(struct trace_parser *parser) | |
902 | { | |
903 | kfree(parser->buffer); | |
904 | } | |
905 | ||
906 | /* | |
907 | * trace_get_user - reads the user input string separated by space | |
908 | * (matched by isspace(ch)) | |
909 | * | |
910 | * For each string found the 'struct trace_parser' is updated, | |
911 | * and the function returns. | |
912 | * | |
913 | * Returns number of bytes read. | |
914 | * | |
915 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
916 | */ | |
917 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
918 | size_t cnt, loff_t *ppos) | |
919 | { | |
920 | char ch; | |
921 | size_t read = 0; | |
922 | ssize_t ret; | |
923 | ||
924 | if (!*ppos) | |
925 | trace_parser_clear(parser); | |
926 | ||
927 | ret = get_user(ch, ubuf++); | |
928 | if (ret) | |
929 | goto out; | |
930 | ||
931 | read++; | |
932 | cnt--; | |
933 | ||
934 | /* | |
935 | * The parser is not finished with the last write, | |
936 | * continue reading the user input without skipping spaces. | |
937 | */ | |
938 | if (!parser->cont) { | |
939 | /* skip white space */ | |
940 | while (cnt && isspace(ch)) { | |
941 | ret = get_user(ch, ubuf++); | |
942 | if (ret) | |
943 | goto out; | |
944 | read++; | |
945 | cnt--; | |
946 | } | |
947 | ||
948 | /* only spaces were written */ | |
949 | if (isspace(ch)) { | |
950 | *ppos += read; | |
951 | ret = read; | |
952 | goto out; | |
953 | } | |
954 | ||
955 | parser->idx = 0; | |
956 | } | |
957 | ||
958 | /* read the non-space input */ | |
959 | while (cnt && !isspace(ch)) { | |
3c235a33 | 960 | if (parser->idx < parser->size - 1) |
b63f39ea | 961 | parser->buffer[parser->idx++] = ch; |
962 | else { | |
963 | ret = -EINVAL; | |
964 | goto out; | |
965 | } | |
966 | ret = get_user(ch, ubuf++); | |
967 | if (ret) | |
968 | goto out; | |
969 | read++; | |
970 | cnt--; | |
971 | } | |
972 | ||
973 | /* We either got finished input or we have to wait for another call. */ | |
974 | if (isspace(ch)) { | |
975 | parser->buffer[parser->idx] = 0; | |
976 | parser->cont = false; | |
057db848 | 977 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 978 | parser->cont = true; |
979 | parser->buffer[parser->idx++] = ch; | |
057db848 SR |
980 | } else { |
981 | ret = -EINVAL; | |
982 | goto out; | |
b63f39ea | 983 | } |
984 | ||
985 | *ppos += read; | |
986 | ret = read; | |
987 | ||
988 | out: | |
989 | return ret; | |
990 | } | |
991 | ||
3a161d99 | 992 | /* TODO add a seq_buf_to_buffer() */ |
b8b94265 | 993 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
994 | { |
995 | int len; | |
3c56819b | 996 | |
5ac48378 | 997 | if (trace_seq_used(s) <= s->seq.readpos) |
3c56819b EGM |
998 | return -EBUSY; |
999 | ||
5ac48378 | 1000 | len = trace_seq_used(s) - s->seq.readpos; |
3c56819b EGM |
1001 | if (cnt > len) |
1002 | cnt = len; | |
3a161d99 | 1003 | memcpy(buf, s->buffer + s->seq.readpos, cnt); |
3c56819b | 1004 | |
3a161d99 | 1005 | s->seq.readpos += cnt; |
3c56819b EGM |
1006 | return cnt; |
1007 | } | |
1008 | ||
0e950173 TB |
1009 | unsigned long __read_mostly tracing_thresh; |
1010 | ||
5d4a9dba | 1011 | #ifdef CONFIG_TRACER_MAX_TRACE |
5d4a9dba SR |
1012 | /* |
1013 | * Copy the new maximum trace into the separate maximum-trace | |
1014 | * structure. (this way the maximum trace is permanently saved, | |
1015 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
1016 | */ | |
1017 | static void | |
1018 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
1019 | { | |
12883efb SRRH |
1020 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
1021 | struct trace_buffer *max_buf = &tr->max_buffer; | |
1022 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
1023 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 1024 | |
12883efb SRRH |
1025 | max_buf->cpu = cpu; |
1026 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 1027 | |
6d9b3fa5 | 1028 | max_data->saved_latency = tr->max_latency; |
8248ac05 SR |
1029 | max_data->critical_start = data->critical_start; |
1030 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 1031 | |
1acaa1b2 | 1032 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 1033 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
1034 | /* |
1035 | * If tsk == current, then use current_uid(), as that does not use | |
1036 | * RCU. The irq tracer can be called out of RCU scope. | |
1037 | */ | |
1038 | if (tsk == current) | |
1039 | max_data->uid = current_uid(); | |
1040 | else | |
1041 | max_data->uid = task_uid(tsk); | |
1042 | ||
8248ac05 SR |
1043 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
1044 | max_data->policy = tsk->policy; | |
1045 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
1046 | |
1047 | /* record this tasks comm */ | |
1048 | tracing_record_cmdline(tsk); | |
1049 | } | |
1050 | ||
4fcdae83 SR |
1051 | /** |
1052 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
1053 | * @tr: tracer | |
1054 | * @tsk: the task with the latency | |
1055 | * @cpu: The cpu that initiated the trace. | |
1056 | * | |
1057 | * Flip the buffers between the @tr and the max_tr and record information | |
1058 | * about which task was the cause of this latency. | |
1059 | */ | |
e309b41d | 1060 | void |
bc0c38d1 SR |
1061 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1062 | { | |
2721e72d | 1063 | struct ring_buffer *buf; |
bc0c38d1 | 1064 | |
2b6080f2 | 1065 | if (tr->stop_count) |
b8de7bd1 SR |
1066 | return; |
1067 | ||
4c11d7ae | 1068 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 1069 | |
45ad21ca | 1070 | if (!tr->allocated_snapshot) { |
debdd57f | 1071 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 1072 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 1073 | return; |
debdd57f | 1074 | } |
34600f0e | 1075 | |
0b9b12c1 | 1076 | arch_spin_lock(&tr->max_lock); |
3928a8a2 | 1077 | |
12883efb SRRH |
1078 | buf = tr->trace_buffer.buffer; |
1079 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
1080 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 1081 | |
bc0c38d1 | 1082 | __update_max_tr(tr, tsk, cpu); |
0b9b12c1 | 1083 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 SR |
1084 | } |
1085 | ||
1086 | /** | |
1087 | * update_max_tr_single - only copy one trace over, and reset the rest | |
1088 | * @tr - tracer | |
1089 | * @tsk - task with the latency | |
1090 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
1091 | * |
1092 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1093 | */ |
e309b41d | 1094 | void |
bc0c38d1 SR |
1095 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1096 | { | |
3928a8a2 | 1097 | int ret; |
bc0c38d1 | 1098 | |
2b6080f2 | 1099 | if (tr->stop_count) |
b8de7bd1 SR |
1100 | return; |
1101 | ||
4c11d7ae | 1102 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1103 | if (!tr->allocated_snapshot) { |
2930e04d | 1104 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1105 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1106 | return; |
2930e04d | 1107 | } |
ef710e10 | 1108 | |
0b9b12c1 | 1109 | arch_spin_lock(&tr->max_lock); |
bc0c38d1 | 1110 | |
12883efb | 1111 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 1112 | |
e8165dbb SR |
1113 | if (ret == -EBUSY) { |
1114 | /* | |
1115 | * We failed to swap the buffer due to a commit taking | |
1116 | * place on this CPU. We fail to record, but we reset | |
1117 | * the max trace buffer (no one writes directly to it) | |
1118 | * and flag that it failed. | |
1119 | */ | |
12883efb | 1120 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1121 | "Failed to swap buffers due to commit in progress\n"); |
1122 | } | |
1123 | ||
e8165dbb | 1124 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1125 | |
1126 | __update_max_tr(tr, tsk, cpu); | |
0b9b12c1 | 1127 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 | 1128 | } |
5d4a9dba | 1129 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1130 | |
e30f53aa | 1131 | static int wait_on_pipe(struct trace_iterator *iter, bool full) |
0d5c6e1c | 1132 | { |
15693458 SRRH |
1133 | /* Iterators are static, they should be filled or empty */ |
1134 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
8b8b3683 | 1135 | return 0; |
0d5c6e1c | 1136 | |
e30f53aa RV |
1137 | return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file, |
1138 | full); | |
0d5c6e1c SR |
1139 | } |
1140 | ||
f4e781c0 SRRH |
1141 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
1142 | static int run_tracer_selftest(struct tracer *type) | |
1143 | { | |
1144 | struct trace_array *tr = &global_trace; | |
1145 | struct tracer *saved_tracer = tr->current_trace; | |
1146 | int ret; | |
0d5c6e1c | 1147 | |
f4e781c0 SRRH |
1148 | if (!type->selftest || tracing_selftest_disabled) |
1149 | return 0; | |
0d5c6e1c SR |
1150 | |
1151 | /* | |
f4e781c0 SRRH |
1152 | * Run a selftest on this tracer. |
1153 | * Here we reset the trace buffer, and set the current | |
1154 | * tracer to be this tracer. The tracer can then run some | |
1155 | * internal tracing to verify that everything is in order. | |
1156 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1157 | */ |
f4e781c0 | 1158 | tracing_reset_online_cpus(&tr->trace_buffer); |
0d5c6e1c | 1159 | |
f4e781c0 SRRH |
1160 | tr->current_trace = type; |
1161 | ||
1162 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1163 | if (type->use_max_tr) { | |
1164 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1165 | if (ring_buffer_expanded) | |
1166 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1167 | RING_BUFFER_ALL_CPUS); | |
1168 | tr->allocated_snapshot = true; | |
1169 | } | |
1170 | #endif | |
1171 | ||
1172 | /* the test is responsible for initializing and enabling */ | |
1173 | pr_info("Testing tracer %s: ", type->name); | |
1174 | ret = type->selftest(type, tr); | |
1175 | /* the test is responsible for resetting too */ | |
1176 | tr->current_trace = saved_tracer; | |
1177 | if (ret) { | |
1178 | printk(KERN_CONT "FAILED!\n"); | |
1179 | /* Add the warning after printing 'FAILED' */ | |
1180 | WARN_ON(1); | |
1181 | return -1; | |
1182 | } | |
1183 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1184 | tracing_reset_online_cpus(&tr->trace_buffer); | |
1185 | ||
1186 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1187 | if (type->use_max_tr) { | |
1188 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1189 | |
f4e781c0 SRRH |
1190 | /* Shrink the max buffer again */ |
1191 | if (ring_buffer_expanded) | |
1192 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1193 | RING_BUFFER_ALL_CPUS); | |
1194 | } | |
1195 | #endif | |
1196 | ||
1197 | printk(KERN_CONT "PASSED\n"); | |
1198 | return 0; | |
1199 | } | |
1200 | #else | |
1201 | static inline int run_tracer_selftest(struct tracer *type) | |
1202 | { | |
1203 | return 0; | |
0d5c6e1c | 1204 | } |
f4e781c0 | 1205 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 1206 | |
4fcdae83 SR |
1207 | /** |
1208 | * register_tracer - register a tracer with the ftrace system. | |
1209 | * @type - the plugin for the tracer | |
1210 | * | |
1211 | * Register a new plugin tracer. | |
1212 | */ | |
bc0c38d1 SR |
1213 | int register_tracer(struct tracer *type) |
1214 | { | |
1215 | struct tracer *t; | |
bc0c38d1 SR |
1216 | int ret = 0; |
1217 | ||
1218 | if (!type->name) { | |
1219 | pr_info("Tracer must have a name\n"); | |
1220 | return -1; | |
1221 | } | |
1222 | ||
24a461d5 | 1223 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
1224 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
1225 | return -1; | |
1226 | } | |
1227 | ||
bc0c38d1 | 1228 | mutex_lock(&trace_types_lock); |
86fa2f60 | 1229 | |
8e1b82e0 FW |
1230 | tracing_selftest_running = true; |
1231 | ||
bc0c38d1 SR |
1232 | for (t = trace_types; t; t = t->next) { |
1233 | if (strcmp(type->name, t->name) == 0) { | |
1234 | /* already found */ | |
ee6c2c1b | 1235 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
1236 | type->name); |
1237 | ret = -1; | |
1238 | goto out; | |
1239 | } | |
1240 | } | |
1241 | ||
adf9f195 FW |
1242 | if (!type->set_flag) |
1243 | type->set_flag = &dummy_set_flag; | |
1244 | if (!type->flags) | |
1245 | type->flags = &dummy_tracer_flags; | |
1246 | else | |
1247 | if (!type->flags->opts) | |
1248 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 | 1249 | |
f4e781c0 SRRH |
1250 | ret = run_tracer_selftest(type); |
1251 | if (ret < 0) | |
1252 | goto out; | |
60a11774 | 1253 | |
bc0c38d1 SR |
1254 | type->next = trace_types; |
1255 | trace_types = type; | |
60a11774 | 1256 | |
bc0c38d1 | 1257 | out: |
8e1b82e0 | 1258 | tracing_selftest_running = false; |
bc0c38d1 SR |
1259 | mutex_unlock(&trace_types_lock); |
1260 | ||
dac74940 SR |
1261 | if (ret || !default_bootup_tracer) |
1262 | goto out_unlock; | |
1263 | ||
ee6c2c1b | 1264 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1265 | goto out_unlock; |
1266 | ||
1267 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1268 | /* Do we want this tracer to start on bootup? */ | |
607e2ea1 | 1269 | tracing_set_tracer(&global_trace, type->name); |
dac74940 SR |
1270 | default_bootup_tracer = NULL; |
1271 | /* disable other selftests, since this will break it. */ | |
55034cd6 | 1272 | tracing_selftest_disabled = true; |
b2821ae6 | 1273 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1274 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1275 | type->name); | |
b2821ae6 | 1276 | #endif |
b2821ae6 | 1277 | |
dac74940 | 1278 | out_unlock: |
bc0c38d1 SR |
1279 | return ret; |
1280 | } | |
1281 | ||
12883efb | 1282 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1283 | { |
12883efb | 1284 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1285 | |
a5416411 HT |
1286 | if (!buffer) |
1287 | return; | |
1288 | ||
f633903a SR |
1289 | ring_buffer_record_disable(buffer); |
1290 | ||
1291 | /* Make sure all commits have finished */ | |
1292 | synchronize_sched(); | |
68179686 | 1293 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1294 | |
1295 | ring_buffer_record_enable(buffer); | |
1296 | } | |
1297 | ||
12883efb | 1298 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1299 | { |
12883efb | 1300 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1301 | int cpu; |
1302 | ||
a5416411 HT |
1303 | if (!buffer) |
1304 | return; | |
1305 | ||
621968cd SR |
1306 | ring_buffer_record_disable(buffer); |
1307 | ||
1308 | /* Make sure all commits have finished */ | |
1309 | synchronize_sched(); | |
1310 | ||
9457158b | 1311 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 PE |
1312 | |
1313 | for_each_online_cpu(cpu) | |
68179686 | 1314 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1315 | |
1316 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1317 | } |
1318 | ||
09d8091c | 1319 | /* Must have trace_types_lock held */ |
873c642f | 1320 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1321 | { |
873c642f SRRH |
1322 | struct trace_array *tr; |
1323 | ||
873c642f | 1324 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
12883efb SRRH |
1325 | tracing_reset_online_cpus(&tr->trace_buffer); |
1326 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1327 | tracing_reset_online_cpus(&tr->max_buffer); | |
1328 | #endif | |
873c642f | 1329 | } |
9456f0fa SR |
1330 | } |
1331 | ||
939c7a4f | 1332 | #define SAVED_CMDLINES_DEFAULT 128 |
2c7eea4c | 1333 | #define NO_CMDLINE_MAP UINT_MAX |
edc35bd7 | 1334 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
939c7a4f YY |
1335 | struct saved_cmdlines_buffer { |
1336 | unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
1337 | unsigned *map_cmdline_to_pid; | |
1338 | unsigned cmdline_num; | |
1339 | int cmdline_idx; | |
1340 | char *saved_cmdlines; | |
1341 | }; | |
1342 | static struct saved_cmdlines_buffer *savedcmd; | |
25b0b44a | 1343 | |
25b0b44a | 1344 | /* temporary disable recording */ |
4fd27358 | 1345 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 | 1346 | |
939c7a4f YY |
1347 | static inline char *get_saved_cmdlines(int idx) |
1348 | { | |
1349 | return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN]; | |
1350 | } | |
1351 | ||
1352 | static inline void set_cmdline(int idx, const char *cmdline) | |
bc0c38d1 | 1353 | { |
939c7a4f YY |
1354 | memcpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); |
1355 | } | |
1356 | ||
1357 | static int allocate_cmdlines_buffer(unsigned int val, | |
1358 | struct saved_cmdlines_buffer *s) | |
1359 | { | |
1360 | s->map_cmdline_to_pid = kmalloc(val * sizeof(*s->map_cmdline_to_pid), | |
1361 | GFP_KERNEL); | |
1362 | if (!s->map_cmdline_to_pid) | |
1363 | return -ENOMEM; | |
1364 | ||
1365 | s->saved_cmdlines = kmalloc(val * TASK_COMM_LEN, GFP_KERNEL); | |
1366 | if (!s->saved_cmdlines) { | |
1367 | kfree(s->map_cmdline_to_pid); | |
1368 | return -ENOMEM; | |
1369 | } | |
1370 | ||
1371 | s->cmdline_idx = 0; | |
1372 | s->cmdline_num = val; | |
1373 | memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP, | |
1374 | sizeof(s->map_pid_to_cmdline)); | |
1375 | memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP, | |
1376 | val * sizeof(*s->map_cmdline_to_pid)); | |
1377 | ||
1378 | return 0; | |
1379 | } | |
1380 | ||
1381 | static int trace_create_savedcmd(void) | |
1382 | { | |
1383 | int ret; | |
1384 | ||
a6af8fbf | 1385 | savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL); |
939c7a4f YY |
1386 | if (!savedcmd) |
1387 | return -ENOMEM; | |
1388 | ||
1389 | ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd); | |
1390 | if (ret < 0) { | |
1391 | kfree(savedcmd); | |
1392 | savedcmd = NULL; | |
1393 | return -ENOMEM; | |
1394 | } | |
1395 | ||
1396 | return 0; | |
bc0c38d1 SR |
1397 | } |
1398 | ||
b5130b1e CE |
1399 | int is_tracing_stopped(void) |
1400 | { | |
2b6080f2 | 1401 | return global_trace.stop_count; |
b5130b1e CE |
1402 | } |
1403 | ||
0f048701 SR |
1404 | /** |
1405 | * tracing_start - quick start of the tracer | |
1406 | * | |
1407 | * If tracing is enabled but was stopped by tracing_stop, | |
1408 | * this will start the tracer back up. | |
1409 | */ | |
1410 | void tracing_start(void) | |
1411 | { | |
1412 | struct ring_buffer *buffer; | |
1413 | unsigned long flags; | |
1414 | ||
1415 | if (tracing_disabled) | |
1416 | return; | |
1417 | ||
2b6080f2 SR |
1418 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1419 | if (--global_trace.stop_count) { | |
1420 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1421 | /* Someone screwed up their debugging */ |
1422 | WARN_ON_ONCE(1); | |
2b6080f2 | 1423 | global_trace.stop_count = 0; |
b06a8301 | 1424 | } |
0f048701 SR |
1425 | goto out; |
1426 | } | |
1427 | ||
a2f80714 | 1428 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1429 | arch_spin_lock(&global_trace.max_lock); |
0f048701 | 1430 | |
12883efb | 1431 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1432 | if (buffer) |
1433 | ring_buffer_record_enable(buffer); | |
1434 | ||
12883efb SRRH |
1435 | #ifdef CONFIG_TRACER_MAX_TRACE |
1436 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1437 | if (buffer) |
1438 | ring_buffer_record_enable(buffer); | |
12883efb | 1439 | #endif |
0f048701 | 1440 | |
0b9b12c1 | 1441 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1442 | |
0f048701 | 1443 | out: |
2b6080f2 SR |
1444 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1445 | } | |
1446 | ||
1447 | static void tracing_start_tr(struct trace_array *tr) | |
1448 | { | |
1449 | struct ring_buffer *buffer; | |
1450 | unsigned long flags; | |
1451 | ||
1452 | if (tracing_disabled) | |
1453 | return; | |
1454 | ||
1455 | /* If global, we need to also start the max tracer */ | |
1456 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1457 | return tracing_start(); | |
1458 | ||
1459 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1460 | ||
1461 | if (--tr->stop_count) { | |
1462 | if (tr->stop_count < 0) { | |
1463 | /* Someone screwed up their debugging */ | |
1464 | WARN_ON_ONCE(1); | |
1465 | tr->stop_count = 0; | |
1466 | } | |
1467 | goto out; | |
1468 | } | |
1469 | ||
12883efb | 1470 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1471 | if (buffer) |
1472 | ring_buffer_record_enable(buffer); | |
1473 | ||
1474 | out: | |
1475 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1476 | } |
1477 | ||
1478 | /** | |
1479 | * tracing_stop - quick stop of the tracer | |
1480 | * | |
1481 | * Light weight way to stop tracing. Use in conjunction with | |
1482 | * tracing_start. | |
1483 | */ | |
1484 | void tracing_stop(void) | |
1485 | { | |
1486 | struct ring_buffer *buffer; | |
1487 | unsigned long flags; | |
1488 | ||
2b6080f2 SR |
1489 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1490 | if (global_trace.stop_count++) | |
0f048701 SR |
1491 | goto out; |
1492 | ||
a2f80714 | 1493 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1494 | arch_spin_lock(&global_trace.max_lock); |
a2f80714 | 1495 | |
12883efb | 1496 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1497 | if (buffer) |
1498 | ring_buffer_record_disable(buffer); | |
1499 | ||
12883efb SRRH |
1500 | #ifdef CONFIG_TRACER_MAX_TRACE |
1501 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1502 | if (buffer) |
1503 | ring_buffer_record_disable(buffer); | |
12883efb | 1504 | #endif |
0f048701 | 1505 | |
0b9b12c1 | 1506 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1507 | |
0f048701 | 1508 | out: |
2b6080f2 SR |
1509 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1510 | } | |
1511 | ||
1512 | static void tracing_stop_tr(struct trace_array *tr) | |
1513 | { | |
1514 | struct ring_buffer *buffer; | |
1515 | unsigned long flags; | |
1516 | ||
1517 | /* If global, we need to also stop the max tracer */ | |
1518 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1519 | return tracing_stop(); | |
1520 | ||
1521 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1522 | if (tr->stop_count++) | |
1523 | goto out; | |
1524 | ||
12883efb | 1525 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1526 | if (buffer) |
1527 | ring_buffer_record_disable(buffer); | |
1528 | ||
1529 | out: | |
1530 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1531 | } |
1532 | ||
e309b41d | 1533 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1534 | |
379cfdac | 1535 | static int trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1536 | { |
a635cf04 | 1537 | unsigned pid, idx; |
bc0c38d1 SR |
1538 | |
1539 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
379cfdac | 1540 | return 0; |
bc0c38d1 SR |
1541 | |
1542 | /* | |
1543 | * It's not the end of the world if we don't get | |
1544 | * the lock, but we also don't want to spin | |
1545 | * nor do we want to disable interrupts, | |
1546 | * so if we miss here, then better luck next time. | |
1547 | */ | |
0199c4e6 | 1548 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
379cfdac | 1549 | return 0; |
bc0c38d1 | 1550 | |
939c7a4f | 1551 | idx = savedcmd->map_pid_to_cmdline[tsk->pid]; |
2c7eea4c | 1552 | if (idx == NO_CMDLINE_MAP) { |
939c7a4f | 1553 | idx = (savedcmd->cmdline_idx + 1) % savedcmd->cmdline_num; |
bc0c38d1 | 1554 | |
a635cf04 CE |
1555 | /* |
1556 | * Check whether the cmdline buffer at idx has a pid | |
1557 | * mapped. We are going to overwrite that entry so we | |
1558 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1559 | * would read the new comm for the old pid. | |
1560 | */ | |
939c7a4f | 1561 | pid = savedcmd->map_cmdline_to_pid[idx]; |
a635cf04 | 1562 | if (pid != NO_CMDLINE_MAP) |
939c7a4f | 1563 | savedcmd->map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; |
bc0c38d1 | 1564 | |
939c7a4f YY |
1565 | savedcmd->map_cmdline_to_pid[idx] = tsk->pid; |
1566 | savedcmd->map_pid_to_cmdline[tsk->pid] = idx; | |
bc0c38d1 | 1567 | |
939c7a4f | 1568 | savedcmd->cmdline_idx = idx; |
bc0c38d1 SR |
1569 | } |
1570 | ||
939c7a4f | 1571 | set_cmdline(idx, tsk->comm); |
bc0c38d1 | 1572 | |
0199c4e6 | 1573 | arch_spin_unlock(&trace_cmdline_lock); |
379cfdac SRRH |
1574 | |
1575 | return 1; | |
bc0c38d1 SR |
1576 | } |
1577 | ||
4c27e756 | 1578 | static void __trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1579 | { |
bc0c38d1 SR |
1580 | unsigned map; |
1581 | ||
4ca53085 SR |
1582 | if (!pid) { |
1583 | strcpy(comm, "<idle>"); | |
1584 | return; | |
1585 | } | |
bc0c38d1 | 1586 | |
74bf4076 SR |
1587 | if (WARN_ON_ONCE(pid < 0)) { |
1588 | strcpy(comm, "<XXX>"); | |
1589 | return; | |
1590 | } | |
1591 | ||
4ca53085 SR |
1592 | if (pid > PID_MAX_DEFAULT) { |
1593 | strcpy(comm, "<...>"); | |
1594 | return; | |
1595 | } | |
bc0c38d1 | 1596 | |
939c7a4f | 1597 | map = savedcmd->map_pid_to_cmdline[pid]; |
50d88758 | 1598 | if (map != NO_CMDLINE_MAP) |
939c7a4f | 1599 | strcpy(comm, get_saved_cmdlines(map)); |
50d88758 TG |
1600 | else |
1601 | strcpy(comm, "<...>"); | |
4c27e756 SRRH |
1602 | } |
1603 | ||
1604 | void trace_find_cmdline(int pid, char comm[]) | |
1605 | { | |
1606 | preempt_disable(); | |
1607 | arch_spin_lock(&trace_cmdline_lock); | |
1608 | ||
1609 | __trace_find_cmdline(pid, comm); | |
bc0c38d1 | 1610 | |
0199c4e6 | 1611 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1612 | preempt_enable(); |
bc0c38d1 SR |
1613 | } |
1614 | ||
e309b41d | 1615 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1616 | { |
0fb9656d | 1617 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1618 | return; |
1619 | ||
7ffbd48d SR |
1620 | if (!__this_cpu_read(trace_cmdline_save)) |
1621 | return; | |
1622 | ||
379cfdac SRRH |
1623 | if (trace_save_cmdline(tsk)) |
1624 | __this_cpu_write(trace_cmdline_save, false); | |
bc0c38d1 SR |
1625 | } |
1626 | ||
45dcd8b8 | 1627 | void |
38697053 SR |
1628 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1629 | int pc) | |
bc0c38d1 SR |
1630 | { |
1631 | struct task_struct *tsk = current; | |
bc0c38d1 | 1632 | |
777e208d SR |
1633 | entry->preempt_count = pc & 0xff; |
1634 | entry->pid = (tsk) ? tsk->pid : 0; | |
1635 | entry->flags = | |
9244489a | 1636 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1637 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1638 | #else |
1639 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1640 | #endif | |
bc0c38d1 SR |
1641 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1642 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
e5137b50 PZ |
1643 | (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) | |
1644 | (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0); | |
bc0c38d1 | 1645 | } |
f413cdb8 | 1646 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1647 | |
e77405ad SR |
1648 | struct ring_buffer_event * |
1649 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1650 | int type, | |
1651 | unsigned long len, | |
1652 | unsigned long flags, int pc) | |
51a763dd ACM |
1653 | { |
1654 | struct ring_buffer_event *event; | |
1655 | ||
e77405ad | 1656 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1657 | if (event != NULL) { |
1658 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1659 | ||
1660 | tracing_generic_entry_update(ent, flags, pc); | |
1661 | ent->type = type; | |
1662 | } | |
1663 | ||
1664 | return event; | |
1665 | } | |
51a763dd | 1666 | |
7ffbd48d SR |
1667 | void |
1668 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1669 | { | |
1670 | __this_cpu_write(trace_cmdline_save, true); | |
1671 | ring_buffer_unlock_commit(buffer, event); | |
1672 | } | |
1673 | ||
e77405ad SR |
1674 | static inline void |
1675 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1676 | struct ring_buffer_event *event, | |
0d5c6e1c | 1677 | unsigned long flags, int pc) |
51a763dd | 1678 | { |
7ffbd48d | 1679 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1680 | |
e77405ad SR |
1681 | ftrace_trace_stack(buffer, flags, 6, pc); |
1682 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1683 | } |
1684 | ||
e77405ad SR |
1685 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1686 | struct ring_buffer_event *event, | |
1687 | unsigned long flags, int pc) | |
07edf712 | 1688 | { |
0d5c6e1c | 1689 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
51a763dd | 1690 | } |
0d5c6e1c | 1691 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1692 | |
2c4a33ab SRRH |
1693 | static struct ring_buffer *temp_buffer; |
1694 | ||
ccb469a1 SR |
1695 | struct ring_buffer_event * |
1696 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
7f1d2f82 | 1697 | struct trace_event_file *trace_file, |
ccb469a1 SR |
1698 | int type, unsigned long len, |
1699 | unsigned long flags, int pc) | |
1700 | { | |
2c4a33ab SRRH |
1701 | struct ring_buffer_event *entry; |
1702 | ||
7f1d2f82 | 1703 | *current_rb = trace_file->tr->trace_buffer.buffer; |
2c4a33ab | 1704 | entry = trace_buffer_lock_reserve(*current_rb, |
ccb469a1 | 1705 | type, len, flags, pc); |
2c4a33ab SRRH |
1706 | /* |
1707 | * If tracing is off, but we have triggers enabled | |
1708 | * we still need to look at the event data. Use the temp_buffer | |
1709 | * to store the trace event for the tigger to use. It's recusive | |
1710 | * safe and will not be recorded anywhere. | |
1711 | */ | |
5d6ad960 | 1712 | if (!entry && trace_file->flags & EVENT_FILE_FL_TRIGGER_COND) { |
2c4a33ab SRRH |
1713 | *current_rb = temp_buffer; |
1714 | entry = trace_buffer_lock_reserve(*current_rb, | |
1715 | type, len, flags, pc); | |
1716 | } | |
1717 | return entry; | |
ccb469a1 SR |
1718 | } |
1719 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
1720 | ||
ef5580d0 | 1721 | struct ring_buffer_event * |
e77405ad SR |
1722 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1723 | int type, unsigned long len, | |
ef5580d0 SR |
1724 | unsigned long flags, int pc) |
1725 | { | |
12883efb | 1726 | *current_rb = global_trace.trace_buffer.buffer; |
e77405ad | 1727 | return trace_buffer_lock_reserve(*current_rb, |
ef5580d0 SR |
1728 | type, len, flags, pc); |
1729 | } | |
94487d6d | 1730 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1731 | |
e77405ad SR |
1732 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1733 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1734 | unsigned long flags, int pc) |
1735 | { | |
0d5c6e1c | 1736 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
07edf712 | 1737 | } |
94487d6d | 1738 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1739 | |
0d5c6e1c SR |
1740 | void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1741 | struct ring_buffer_event *event, | |
1742 | unsigned long flags, int pc, | |
1743 | struct pt_regs *regs) | |
1fd8df2c | 1744 | { |
7ffbd48d | 1745 | __buffer_unlock_commit(buffer, event); |
1fd8df2c MH |
1746 | |
1747 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1748 | ftrace_trace_userstack(buffer, flags, pc); | |
1749 | } | |
0d5c6e1c | 1750 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1751 | |
e77405ad SR |
1752 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1753 | struct ring_buffer_event *event) | |
77d9f465 | 1754 | { |
e77405ad | 1755 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1756 | } |
12acd473 | 1757 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1758 | |
e309b41d | 1759 | void |
7be42151 | 1760 | trace_function(struct trace_array *tr, |
38697053 SR |
1761 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1762 | int pc) | |
bc0c38d1 | 1763 | { |
2425bcb9 | 1764 | struct trace_event_call *call = &event_function; |
12883efb | 1765 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 1766 | struct ring_buffer_event *event; |
777e208d | 1767 | struct ftrace_entry *entry; |
bc0c38d1 | 1768 | |
d769041f | 1769 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1770 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1771 | return; |
1772 | ||
e77405ad | 1773 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1774 | flags, pc); |
3928a8a2 SR |
1775 | if (!event) |
1776 | return; | |
1777 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1778 | entry->ip = ip; |
1779 | entry->parent_ip = parent_ip; | |
e1112b4d | 1780 | |
f306cc82 | 1781 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1782 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1783 | } |
1784 | ||
c0a0d0d3 | 1785 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1786 | |
1787 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1788 | struct ftrace_stack { | |
1789 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1790 | }; | |
1791 | ||
1792 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1793 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1794 | ||
e77405ad | 1795 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1796 | unsigned long flags, |
1fd8df2c | 1797 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1798 | { |
2425bcb9 | 1799 | struct trace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1800 | struct ring_buffer_event *event; |
777e208d | 1801 | struct stack_entry *entry; |
86387f7e | 1802 | struct stack_trace trace; |
4a9bd3f1 SR |
1803 | int use_stack; |
1804 | int size = FTRACE_STACK_ENTRIES; | |
1805 | ||
1806 | trace.nr_entries = 0; | |
1807 | trace.skip = skip; | |
1808 | ||
1809 | /* | |
1810 | * Since events can happen in NMIs there's no safe way to | |
1811 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1812 | * or NMI comes in, it will just have to use the default | |
1813 | * FTRACE_STACK_SIZE. | |
1814 | */ | |
1815 | preempt_disable_notrace(); | |
1816 | ||
82146529 | 1817 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
1818 | /* |
1819 | * We don't need any atomic variables, just a barrier. | |
1820 | * If an interrupt comes in, we don't care, because it would | |
1821 | * have exited and put the counter back to what we want. | |
1822 | * We just need a barrier to keep gcc from moving things | |
1823 | * around. | |
1824 | */ | |
1825 | barrier(); | |
1826 | if (use_stack == 1) { | |
bdffd893 | 1827 | trace.entries = this_cpu_ptr(ftrace_stack.calls); |
4a9bd3f1 SR |
1828 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; |
1829 | ||
1830 | if (regs) | |
1831 | save_stack_trace_regs(regs, &trace); | |
1832 | else | |
1833 | save_stack_trace(&trace); | |
1834 | ||
1835 | if (trace.nr_entries > size) | |
1836 | size = trace.nr_entries; | |
1837 | } else | |
1838 | /* From now on, use_stack is a boolean */ | |
1839 | use_stack = 0; | |
1840 | ||
1841 | size *= sizeof(unsigned long); | |
86387f7e | 1842 | |
e77405ad | 1843 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1844 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1845 | if (!event) |
4a9bd3f1 SR |
1846 | goto out; |
1847 | entry = ring_buffer_event_data(event); | |
86387f7e | 1848 | |
4a9bd3f1 SR |
1849 | memset(&entry->caller, 0, size); |
1850 | ||
1851 | if (use_stack) | |
1852 | memcpy(&entry->caller, trace.entries, | |
1853 | trace.nr_entries * sizeof(unsigned long)); | |
1854 | else { | |
1855 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1856 | trace.entries = entry->caller; | |
1857 | if (regs) | |
1858 | save_stack_trace_regs(regs, &trace); | |
1859 | else | |
1860 | save_stack_trace(&trace); | |
1861 | } | |
1862 | ||
1863 | entry->size = trace.nr_entries; | |
86387f7e | 1864 | |
f306cc82 | 1865 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1866 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1867 | |
1868 | out: | |
1869 | /* Again, don't let gcc optimize things here */ | |
1870 | barrier(); | |
82146529 | 1871 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
1872 | preempt_enable_notrace(); |
1873 | ||
f0a920d5 IM |
1874 | } |
1875 | ||
1fd8df2c MH |
1876 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1877 | int skip, int pc, struct pt_regs *regs) | |
1878 | { | |
1879 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1880 | return; | |
1881 | ||
1882 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1883 | } | |
1884 | ||
e77405ad SR |
1885 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1886 | int skip, int pc) | |
53614991 SR |
1887 | { |
1888 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1889 | return; | |
1890 | ||
1fd8df2c | 1891 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1892 | } |
1893 | ||
c0a0d0d3 FW |
1894 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1895 | int pc) | |
38697053 | 1896 | { |
12883efb | 1897 | __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); |
38697053 SR |
1898 | } |
1899 | ||
03889384 SR |
1900 | /** |
1901 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 1902 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 1903 | */ |
c142be8e | 1904 | void trace_dump_stack(int skip) |
03889384 SR |
1905 | { |
1906 | unsigned long flags; | |
1907 | ||
1908 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1909 | return; |
03889384 SR |
1910 | |
1911 | local_save_flags(flags); | |
1912 | ||
c142be8e SRRH |
1913 | /* |
1914 | * Skip 3 more, seems to get us at the caller of | |
1915 | * this function. | |
1916 | */ | |
1917 | skip += 3; | |
1918 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, | |
1919 | flags, skip, preempt_count(), NULL); | |
03889384 SR |
1920 | } |
1921 | ||
91e86e56 SR |
1922 | static DEFINE_PER_CPU(int, user_stack_count); |
1923 | ||
e77405ad SR |
1924 | void |
1925 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1926 | { |
2425bcb9 | 1927 | struct trace_event_call *call = &event_user_stack; |
8d7c6a96 | 1928 | struct ring_buffer_event *event; |
02b67518 TE |
1929 | struct userstack_entry *entry; |
1930 | struct stack_trace trace; | |
02b67518 TE |
1931 | |
1932 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1933 | return; | |
1934 | ||
b6345879 SR |
1935 | /* |
1936 | * NMIs can not handle page faults, even with fix ups. | |
1937 | * The save user stack can (and often does) fault. | |
1938 | */ | |
1939 | if (unlikely(in_nmi())) | |
1940 | return; | |
02b67518 | 1941 | |
91e86e56 SR |
1942 | /* |
1943 | * prevent recursion, since the user stack tracing may | |
1944 | * trigger other kernel events. | |
1945 | */ | |
1946 | preempt_disable(); | |
1947 | if (__this_cpu_read(user_stack_count)) | |
1948 | goto out; | |
1949 | ||
1950 | __this_cpu_inc(user_stack_count); | |
1951 | ||
e77405ad | 1952 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1953 | sizeof(*entry), flags, pc); |
02b67518 | 1954 | if (!event) |
1dbd1951 | 1955 | goto out_drop_count; |
02b67518 | 1956 | entry = ring_buffer_event_data(event); |
02b67518 | 1957 | |
48659d31 | 1958 | entry->tgid = current->tgid; |
02b67518 TE |
1959 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1960 | ||
1961 | trace.nr_entries = 0; | |
1962 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1963 | trace.skip = 0; | |
1964 | trace.entries = entry->caller; | |
1965 | ||
1966 | save_stack_trace_user(&trace); | |
f306cc82 | 1967 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1968 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1969 | |
1dbd1951 | 1970 | out_drop_count: |
91e86e56 | 1971 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1972 | out: |
1973 | preempt_enable(); | |
02b67518 TE |
1974 | } |
1975 | ||
4fd27358 HE |
1976 | #ifdef UNUSED |
1977 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1978 | { |
7be42151 | 1979 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1980 | } |
4fd27358 | 1981 | #endif /* UNUSED */ |
02b67518 | 1982 | |
c0a0d0d3 FW |
1983 | #endif /* CONFIG_STACKTRACE */ |
1984 | ||
07d777fe SR |
1985 | /* created for use with alloc_percpu */ |
1986 | struct trace_buffer_struct { | |
1987 | char buffer[TRACE_BUF_SIZE]; | |
1988 | }; | |
1989 | ||
1990 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1991 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1992 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1993 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1994 | ||
1995 | /* | |
1996 | * The buffer used is dependent on the context. There is a per cpu | |
1997 | * buffer for normal context, softirq contex, hard irq context and | |
1998 | * for NMI context. Thise allows for lockless recording. | |
1999 | * | |
2000 | * Note, if the buffers failed to be allocated, then this returns NULL | |
2001 | */ | |
2002 | static char *get_trace_buf(void) | |
2003 | { | |
2004 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
2005 | |
2006 | /* | |
2007 | * If we have allocated per cpu buffers, then we do not | |
2008 | * need to do any locking. | |
2009 | */ | |
2010 | if (in_nmi()) | |
2011 | percpu_buffer = trace_percpu_nmi_buffer; | |
2012 | else if (in_irq()) | |
2013 | percpu_buffer = trace_percpu_irq_buffer; | |
2014 | else if (in_softirq()) | |
2015 | percpu_buffer = trace_percpu_sirq_buffer; | |
2016 | else | |
2017 | percpu_buffer = trace_percpu_buffer; | |
2018 | ||
2019 | if (!percpu_buffer) | |
2020 | return NULL; | |
2021 | ||
d8a0349c | 2022 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
2023 | } |
2024 | ||
2025 | static int alloc_percpu_trace_buffer(void) | |
2026 | { | |
2027 | struct trace_buffer_struct *buffers; | |
2028 | struct trace_buffer_struct *sirq_buffers; | |
2029 | struct trace_buffer_struct *irq_buffers; | |
2030 | struct trace_buffer_struct *nmi_buffers; | |
2031 | ||
2032 | buffers = alloc_percpu(struct trace_buffer_struct); | |
2033 | if (!buffers) | |
2034 | goto err_warn; | |
2035 | ||
2036 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
2037 | if (!sirq_buffers) | |
2038 | goto err_sirq; | |
2039 | ||
2040 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
2041 | if (!irq_buffers) | |
2042 | goto err_irq; | |
2043 | ||
2044 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
2045 | if (!nmi_buffers) | |
2046 | goto err_nmi; | |
2047 | ||
2048 | trace_percpu_buffer = buffers; | |
2049 | trace_percpu_sirq_buffer = sirq_buffers; | |
2050 | trace_percpu_irq_buffer = irq_buffers; | |
2051 | trace_percpu_nmi_buffer = nmi_buffers; | |
2052 | ||
2053 | return 0; | |
2054 | ||
2055 | err_nmi: | |
2056 | free_percpu(irq_buffers); | |
2057 | err_irq: | |
2058 | free_percpu(sirq_buffers); | |
2059 | err_sirq: | |
2060 | free_percpu(buffers); | |
2061 | err_warn: | |
2062 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
2063 | return -ENOMEM; | |
2064 | } | |
2065 | ||
81698831 SR |
2066 | static int buffers_allocated; |
2067 | ||
07d777fe SR |
2068 | void trace_printk_init_buffers(void) |
2069 | { | |
07d777fe SR |
2070 | if (buffers_allocated) |
2071 | return; | |
2072 | ||
2073 | if (alloc_percpu_trace_buffer()) | |
2074 | return; | |
2075 | ||
2184db46 SR |
2076 | /* trace_printk() is for debug use only. Don't use it in production. */ |
2077 | ||
69a1c994 BP |
2078 | pr_warning("\n"); |
2079 | pr_warning("**********************************************************\n"); | |
2184db46 SR |
2080 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); |
2081 | pr_warning("** **\n"); | |
2082 | pr_warning("** trace_printk() being used. Allocating extra memory. **\n"); | |
2083 | pr_warning("** **\n"); | |
2084 | pr_warning("** This means that this is a DEBUG kernel and it is **\n"); | |
eff264ef | 2085 | pr_warning("** unsafe for production use. **\n"); |
2184db46 SR |
2086 | pr_warning("** **\n"); |
2087 | pr_warning("** If you see this message and you are not debugging **\n"); | |
2088 | pr_warning("** the kernel, report this immediately to your vendor! **\n"); | |
2089 | pr_warning("** **\n"); | |
2090 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
2091 | pr_warning("**********************************************************\n"); | |
07d777fe | 2092 | |
b382ede6 SR |
2093 | /* Expand the buffers to set size */ |
2094 | tracing_update_buffers(); | |
2095 | ||
07d777fe | 2096 | buffers_allocated = 1; |
81698831 SR |
2097 | |
2098 | /* | |
2099 | * trace_printk_init_buffers() can be called by modules. | |
2100 | * If that happens, then we need to start cmdline recording | |
2101 | * directly here. If the global_trace.buffer is already | |
2102 | * allocated here, then this was called by module code. | |
2103 | */ | |
12883efb | 2104 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
2105 | tracing_start_cmdline_record(); |
2106 | } | |
2107 | ||
2108 | void trace_printk_start_comm(void) | |
2109 | { | |
2110 | /* Start tracing comms if trace printk is set */ | |
2111 | if (!buffers_allocated) | |
2112 | return; | |
2113 | tracing_start_cmdline_record(); | |
2114 | } | |
2115 | ||
2116 | static void trace_printk_start_stop_comm(int enabled) | |
2117 | { | |
2118 | if (!buffers_allocated) | |
2119 | return; | |
2120 | ||
2121 | if (enabled) | |
2122 | tracing_start_cmdline_record(); | |
2123 | else | |
2124 | tracing_stop_cmdline_record(); | |
07d777fe SR |
2125 | } |
2126 | ||
769b0441 | 2127 | /** |
48ead020 | 2128 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
2129 | * |
2130 | */ | |
40ce74f1 | 2131 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 2132 | { |
2425bcb9 | 2133 | struct trace_event_call *call = &event_bprint; |
769b0441 | 2134 | struct ring_buffer_event *event; |
e77405ad | 2135 | struct ring_buffer *buffer; |
769b0441 | 2136 | struct trace_array *tr = &global_trace; |
48ead020 | 2137 | struct bprint_entry *entry; |
769b0441 | 2138 | unsigned long flags; |
07d777fe SR |
2139 | char *tbuffer; |
2140 | int len = 0, size, pc; | |
769b0441 FW |
2141 | |
2142 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
2143 | return 0; | |
2144 | ||
2145 | /* Don't pollute graph traces with trace_vprintk internals */ | |
2146 | pause_graph_tracing(); | |
2147 | ||
2148 | pc = preempt_count(); | |
5168ae50 | 2149 | preempt_disable_notrace(); |
769b0441 | 2150 | |
07d777fe SR |
2151 | tbuffer = get_trace_buf(); |
2152 | if (!tbuffer) { | |
2153 | len = 0; | |
769b0441 | 2154 | goto out; |
07d777fe | 2155 | } |
769b0441 | 2156 | |
07d777fe | 2157 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 2158 | |
07d777fe SR |
2159 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
2160 | goto out; | |
769b0441 | 2161 | |
07d777fe | 2162 | local_save_flags(flags); |
769b0441 | 2163 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 2164 | buffer = tr->trace_buffer.buffer; |
e77405ad SR |
2165 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
2166 | flags, pc); | |
769b0441 | 2167 | if (!event) |
07d777fe | 2168 | goto out; |
769b0441 FW |
2169 | entry = ring_buffer_event_data(event); |
2170 | entry->ip = ip; | |
769b0441 FW |
2171 | entry->fmt = fmt; |
2172 | ||
07d777fe | 2173 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
f306cc82 | 2174 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2175 | __buffer_unlock_commit(buffer, event); |
d931369b SR |
2176 | ftrace_trace_stack(buffer, flags, 6, pc); |
2177 | } | |
769b0441 | 2178 | |
769b0441 | 2179 | out: |
5168ae50 | 2180 | preempt_enable_notrace(); |
769b0441 FW |
2181 | unpause_graph_tracing(); |
2182 | ||
2183 | return len; | |
2184 | } | |
48ead020 FW |
2185 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
2186 | ||
12883efb SRRH |
2187 | static int |
2188 | __trace_array_vprintk(struct ring_buffer *buffer, | |
2189 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 2190 | { |
2425bcb9 | 2191 | struct trace_event_call *call = &event_print; |
48ead020 | 2192 | struct ring_buffer_event *event; |
07d777fe | 2193 | int len = 0, size, pc; |
48ead020 | 2194 | struct print_entry *entry; |
07d777fe SR |
2195 | unsigned long flags; |
2196 | char *tbuffer; | |
48ead020 FW |
2197 | |
2198 | if (tracing_disabled || tracing_selftest_running) | |
2199 | return 0; | |
2200 | ||
07d777fe SR |
2201 | /* Don't pollute graph traces with trace_vprintk internals */ |
2202 | pause_graph_tracing(); | |
2203 | ||
48ead020 FW |
2204 | pc = preempt_count(); |
2205 | preempt_disable_notrace(); | |
48ead020 | 2206 | |
07d777fe SR |
2207 | |
2208 | tbuffer = get_trace_buf(); | |
2209 | if (!tbuffer) { | |
2210 | len = 0; | |
48ead020 | 2211 | goto out; |
07d777fe | 2212 | } |
48ead020 | 2213 | |
3558a5ac | 2214 | len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
48ead020 | 2215 | |
07d777fe | 2216 | local_save_flags(flags); |
48ead020 | 2217 | size = sizeof(*entry) + len + 1; |
e77405ad | 2218 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
07d777fe | 2219 | flags, pc); |
48ead020 | 2220 | if (!event) |
07d777fe | 2221 | goto out; |
48ead020 | 2222 | entry = ring_buffer_event_data(event); |
c13d2f7c | 2223 | entry->ip = ip; |
48ead020 | 2224 | |
3558a5ac | 2225 | memcpy(&entry->buf, tbuffer, len + 1); |
f306cc82 | 2226 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2227 | __buffer_unlock_commit(buffer, event); |
07d777fe | 2228 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 2229 | } |
48ead020 FW |
2230 | out: |
2231 | preempt_enable_notrace(); | |
07d777fe | 2232 | unpause_graph_tracing(); |
48ead020 FW |
2233 | |
2234 | return len; | |
2235 | } | |
659372d3 | 2236 | |
12883efb SRRH |
2237 | int trace_array_vprintk(struct trace_array *tr, |
2238 | unsigned long ip, const char *fmt, va_list args) | |
2239 | { | |
2240 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
2241 | } | |
2242 | ||
2243 | int trace_array_printk(struct trace_array *tr, | |
2244 | unsigned long ip, const char *fmt, ...) | |
2245 | { | |
2246 | int ret; | |
2247 | va_list ap; | |
2248 | ||
2249 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2250 | return 0; | |
2251 | ||
2252 | va_start(ap, fmt); | |
2253 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
2254 | va_end(ap); | |
2255 | return ret; | |
2256 | } | |
2257 | ||
2258 | int trace_array_printk_buf(struct ring_buffer *buffer, | |
2259 | unsigned long ip, const char *fmt, ...) | |
2260 | { | |
2261 | int ret; | |
2262 | va_list ap; | |
2263 | ||
2264 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2265 | return 0; | |
2266 | ||
2267 | va_start(ap, fmt); | |
2268 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
2269 | va_end(ap); | |
2270 | return ret; | |
2271 | } | |
2272 | ||
659372d3 SR |
2273 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
2274 | { | |
a813a159 | 2275 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 2276 | } |
769b0441 FW |
2277 | EXPORT_SYMBOL_GPL(trace_vprintk); |
2278 | ||
e2ac8ef5 | 2279 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 2280 | { |
6d158a81 SR |
2281 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
2282 | ||
5a90f577 | 2283 | iter->idx++; |
6d158a81 SR |
2284 | if (buf_iter) |
2285 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
2286 | } |
2287 | ||
e309b41d | 2288 | static struct trace_entry * |
bc21b478 SR |
2289 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
2290 | unsigned long *lost_events) | |
dd0e545f | 2291 | { |
3928a8a2 | 2292 | struct ring_buffer_event *event; |
6d158a81 | 2293 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 2294 | |
d769041f SR |
2295 | if (buf_iter) |
2296 | event = ring_buffer_iter_peek(buf_iter, ts); | |
2297 | else | |
12883efb | 2298 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 2299 | lost_events); |
d769041f | 2300 | |
4a9bd3f1 SR |
2301 | if (event) { |
2302 | iter->ent_size = ring_buffer_event_length(event); | |
2303 | return ring_buffer_event_data(event); | |
2304 | } | |
2305 | iter->ent_size = 0; | |
2306 | return NULL; | |
dd0e545f | 2307 | } |
d769041f | 2308 | |
dd0e545f | 2309 | static struct trace_entry * |
bc21b478 SR |
2310 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
2311 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 2312 | { |
12883efb | 2313 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 2314 | struct trace_entry *ent, *next = NULL; |
aa27497c | 2315 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 2316 | int cpu_file = iter->cpu_file; |
3928a8a2 | 2317 | u64 next_ts = 0, ts; |
bc0c38d1 | 2318 | int next_cpu = -1; |
12b5da34 | 2319 | int next_size = 0; |
bc0c38d1 SR |
2320 | int cpu; |
2321 | ||
b04cc6b1 FW |
2322 | /* |
2323 | * If we are in a per_cpu trace file, don't bother by iterating over | |
2324 | * all cpu and peek directly. | |
2325 | */ | |
ae3b5093 | 2326 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
2327 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
2328 | return NULL; | |
bc21b478 | 2329 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
2330 | if (ent_cpu) |
2331 | *ent_cpu = cpu_file; | |
2332 | ||
2333 | return ent; | |
2334 | } | |
2335 | ||
ab46428c | 2336 | for_each_tracing_cpu(cpu) { |
dd0e545f | 2337 | |
3928a8a2 SR |
2338 | if (ring_buffer_empty_cpu(buffer, cpu)) |
2339 | continue; | |
dd0e545f | 2340 | |
bc21b478 | 2341 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 2342 | |
cdd31cd2 IM |
2343 | /* |
2344 | * Pick the entry with the smallest timestamp: | |
2345 | */ | |
3928a8a2 | 2346 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
2347 | next = ent; |
2348 | next_cpu = cpu; | |
3928a8a2 | 2349 | next_ts = ts; |
bc21b478 | 2350 | next_lost = lost_events; |
12b5da34 | 2351 | next_size = iter->ent_size; |
bc0c38d1 SR |
2352 | } |
2353 | } | |
2354 | ||
12b5da34 SR |
2355 | iter->ent_size = next_size; |
2356 | ||
bc0c38d1 SR |
2357 | if (ent_cpu) |
2358 | *ent_cpu = next_cpu; | |
2359 | ||
3928a8a2 SR |
2360 | if (ent_ts) |
2361 | *ent_ts = next_ts; | |
2362 | ||
bc21b478 SR |
2363 | if (missing_events) |
2364 | *missing_events = next_lost; | |
2365 | ||
bc0c38d1 SR |
2366 | return next; |
2367 | } | |
2368 | ||
dd0e545f | 2369 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
2370 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
2371 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 2372 | { |
bc21b478 | 2373 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
2374 | } |
2375 | ||
2376 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 2377 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 2378 | { |
bc21b478 SR |
2379 | iter->ent = __find_next_entry(iter, &iter->cpu, |
2380 | &iter->lost_events, &iter->ts); | |
dd0e545f | 2381 | |
3928a8a2 | 2382 | if (iter->ent) |
e2ac8ef5 | 2383 | trace_iterator_increment(iter); |
dd0e545f | 2384 | |
3928a8a2 | 2385 | return iter->ent ? iter : NULL; |
b3806b43 | 2386 | } |
bc0c38d1 | 2387 | |
e309b41d | 2388 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 2389 | { |
12883efb | 2390 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 2391 | &iter->lost_events); |
bc0c38d1 SR |
2392 | } |
2393 | ||
e309b41d | 2394 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
2395 | { |
2396 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 2397 | int i = (int)*pos; |
4e3c3333 | 2398 | void *ent; |
bc0c38d1 | 2399 | |
a63ce5b3 SR |
2400 | WARN_ON_ONCE(iter->leftover); |
2401 | ||
bc0c38d1 SR |
2402 | (*pos)++; |
2403 | ||
2404 | /* can't go backwards */ | |
2405 | if (iter->idx > i) | |
2406 | return NULL; | |
2407 | ||
2408 | if (iter->idx < 0) | |
955b61e5 | 2409 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2410 | else |
2411 | ent = iter; | |
2412 | ||
2413 | while (ent && iter->idx < i) | |
955b61e5 | 2414 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2415 | |
2416 | iter->pos = *pos; | |
2417 | ||
bc0c38d1 SR |
2418 | return ent; |
2419 | } | |
2420 | ||
955b61e5 | 2421 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 2422 | { |
2f26ebd5 SR |
2423 | struct ring_buffer_event *event; |
2424 | struct ring_buffer_iter *buf_iter; | |
2425 | unsigned long entries = 0; | |
2426 | u64 ts; | |
2427 | ||
12883efb | 2428 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 2429 | |
6d158a81 SR |
2430 | buf_iter = trace_buffer_iter(iter, cpu); |
2431 | if (!buf_iter) | |
2f26ebd5 SR |
2432 | return; |
2433 | ||
2f26ebd5 SR |
2434 | ring_buffer_iter_reset(buf_iter); |
2435 | ||
2436 | /* | |
2437 | * We could have the case with the max latency tracers | |
2438 | * that a reset never took place on a cpu. This is evident | |
2439 | * by the timestamp being before the start of the buffer. | |
2440 | */ | |
2441 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 2442 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
2443 | break; |
2444 | entries++; | |
2445 | ring_buffer_read(buf_iter, NULL); | |
2446 | } | |
2447 | ||
12883efb | 2448 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2449 | } |
2450 | ||
d7350c3f | 2451 | /* |
d7350c3f FW |
2452 | * The current tracer is copied to avoid a global locking |
2453 | * all around. | |
2454 | */ | |
bc0c38d1 SR |
2455 | static void *s_start(struct seq_file *m, loff_t *pos) |
2456 | { | |
2457 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2458 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2459 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2460 | void *p = NULL; |
2461 | loff_t l = 0; | |
3928a8a2 | 2462 | int cpu; |
bc0c38d1 | 2463 | |
2fd196ec HT |
2464 | /* |
2465 | * copy the tracer to avoid using a global lock all around. | |
2466 | * iter->trace is a copy of current_trace, the pointer to the | |
2467 | * name may be used instead of a strcmp(), as iter->trace->name | |
2468 | * will point to the same string as current_trace->name. | |
2469 | */ | |
bc0c38d1 | 2470 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2471 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2472 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2473 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2474 | |
12883efb | 2475 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2476 | if (iter->snapshot && iter->trace->use_max_tr) |
2477 | return ERR_PTR(-EBUSY); | |
12883efb | 2478 | #endif |
debdd57f HT |
2479 | |
2480 | if (!iter->snapshot) | |
2481 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2482 | |
bc0c38d1 SR |
2483 | if (*pos != iter->pos) { |
2484 | iter->ent = NULL; | |
2485 | iter->cpu = 0; | |
2486 | iter->idx = -1; | |
2487 | ||
ae3b5093 | 2488 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2489 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2490 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2491 | } else |
2f26ebd5 | 2492 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2493 | |
ac91d854 | 2494 | iter->leftover = 0; |
bc0c38d1 SR |
2495 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2496 | ; | |
2497 | ||
2498 | } else { | |
a63ce5b3 SR |
2499 | /* |
2500 | * If we overflowed the seq_file before, then we want | |
2501 | * to just reuse the trace_seq buffer again. | |
2502 | */ | |
2503 | if (iter->leftover) | |
2504 | p = iter; | |
2505 | else { | |
2506 | l = *pos - 1; | |
2507 | p = s_next(m, p, &l); | |
2508 | } | |
bc0c38d1 SR |
2509 | } |
2510 | ||
4f535968 | 2511 | trace_event_read_lock(); |
7e53bd42 | 2512 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2513 | return p; |
2514 | } | |
2515 | ||
2516 | static void s_stop(struct seq_file *m, void *p) | |
2517 | { | |
7e53bd42 LJ |
2518 | struct trace_iterator *iter = m->private; |
2519 | ||
12883efb | 2520 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2521 | if (iter->snapshot && iter->trace->use_max_tr) |
2522 | return; | |
12883efb | 2523 | #endif |
debdd57f HT |
2524 | |
2525 | if (!iter->snapshot) | |
2526 | atomic_dec(&trace_record_cmdline_disabled); | |
12883efb | 2527 | |
7e53bd42 | 2528 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2529 | trace_event_read_unlock(); |
bc0c38d1 SR |
2530 | } |
2531 | ||
39eaf7ef | 2532 | static void |
12883efb SRRH |
2533 | get_total_entries(struct trace_buffer *buf, |
2534 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
2535 | { |
2536 | unsigned long count; | |
2537 | int cpu; | |
2538 | ||
2539 | *total = 0; | |
2540 | *entries = 0; | |
2541 | ||
2542 | for_each_tracing_cpu(cpu) { | |
12883efb | 2543 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2544 | /* |
2545 | * If this buffer has skipped entries, then we hold all | |
2546 | * entries for the trace and we need to ignore the | |
2547 | * ones before the time stamp. | |
2548 | */ | |
12883efb SRRH |
2549 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
2550 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2551 | /* total is the same as the entries */ |
2552 | *total += count; | |
2553 | } else | |
2554 | *total += count + | |
12883efb | 2555 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2556 | *entries += count; |
2557 | } | |
2558 | } | |
2559 | ||
e309b41d | 2560 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2561 | { |
d79ac28f RV |
2562 | seq_puts(m, "# _------=> CPU# \n" |
2563 | "# / _-----=> irqs-off \n" | |
2564 | "# | / _----=> need-resched \n" | |
2565 | "# || / _---=> hardirq/softirq \n" | |
2566 | "# ||| / _--=> preempt-depth \n" | |
2567 | "# |||| / delay \n" | |
2568 | "# cmd pid ||||| time | caller \n" | |
2569 | "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2570 | } |
2571 | ||
12883efb | 2572 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 2573 | { |
39eaf7ef SR |
2574 | unsigned long total; |
2575 | unsigned long entries; | |
2576 | ||
12883efb | 2577 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
2578 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
2579 | entries, total, num_online_cpus()); | |
2580 | seq_puts(m, "#\n"); | |
2581 | } | |
2582 | ||
12883efb | 2583 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) |
39eaf7ef | 2584 | { |
12883efb | 2585 | print_event_info(buf, m); |
d79ac28f RV |
2586 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n" |
2587 | "# | | | | |\n"); | |
bc0c38d1 SR |
2588 | } |
2589 | ||
12883efb | 2590 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) |
77271ce4 | 2591 | { |
12883efb | 2592 | print_event_info(buf, m); |
d79ac28f RV |
2593 | seq_puts(m, "# _-----=> irqs-off\n" |
2594 | "# / _----=> need-resched\n" | |
2595 | "# | / _---=> hardirq/softirq\n" | |
2596 | "# || / _--=> preempt-depth\n" | |
2597 | "# ||| / delay\n" | |
2598 | "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n" | |
2599 | "# | | | |||| | |\n"); | |
77271ce4 | 2600 | } |
bc0c38d1 | 2601 | |
62b915f1 | 2602 | void |
bc0c38d1 SR |
2603 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2604 | { | |
2605 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
12883efb SRRH |
2606 | struct trace_buffer *buf = iter->trace_buffer; |
2607 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 2608 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2609 | unsigned long entries; |
2610 | unsigned long total; | |
bc0c38d1 SR |
2611 | const char *name = "preemption"; |
2612 | ||
d840f718 | 2613 | name = type->name; |
bc0c38d1 | 2614 | |
12883efb | 2615 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 2616 | |
888b55dc | 2617 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2618 | name, UTS_RELEASE); |
888b55dc | 2619 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2620 | "---------------------------------\n"); |
888b55dc | 2621 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2622 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2623 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2624 | entries, |
4c11d7ae | 2625 | total, |
12883efb | 2626 | buf->cpu, |
bc0c38d1 SR |
2627 | #if defined(CONFIG_PREEMPT_NONE) |
2628 | "server", | |
2629 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2630 | "desktop", | |
b5c21b45 | 2631 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2632 | "preempt", |
2633 | #else | |
2634 | "unknown", | |
2635 | #endif | |
2636 | /* These are reserved for later use */ | |
2637 | 0, 0, 0, 0); | |
2638 | #ifdef CONFIG_SMP | |
2639 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2640 | #else | |
2641 | seq_puts(m, ")\n"); | |
2642 | #endif | |
888b55dc KM |
2643 | seq_puts(m, "# -----------------\n"); |
2644 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2645 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2646 | data->comm, data->pid, |
2647 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2648 | data->policy, data->rt_priority); |
888b55dc | 2649 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2650 | |
2651 | if (data->critical_start) { | |
888b55dc | 2652 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2653 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2654 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2655 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2656 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2657 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2658 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2659 | } |
2660 | ||
888b55dc | 2661 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2662 | } |
2663 | ||
a309720c SR |
2664 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2665 | { | |
2666 | struct trace_seq *s = &iter->seq; | |
2667 | ||
12ef7d44 SR |
2668 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2669 | return; | |
2670 | ||
2671 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2672 | return; | |
2673 | ||
4462344e | 2674 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2675 | return; |
2676 | ||
12883efb | 2677 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
2678 | return; |
2679 | ||
4462344e | 2680 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2681 | |
2682 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2683 | if (iter->idx > 1) | |
2684 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2685 | iter->cpu); | |
a309720c SR |
2686 | } |
2687 | ||
2c4f035f | 2688 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2689 | { |
214023c3 | 2690 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2691 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2692 | struct trace_entry *entry; |
f633cef0 | 2693 | struct trace_event *event; |
bc0c38d1 | 2694 | |
4e3c3333 | 2695 | entry = iter->ent; |
dd0e545f | 2696 | |
a309720c SR |
2697 | test_cpu_buff_start(iter); |
2698 | ||
c4a8e8be | 2699 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2700 | |
c4a8e8be | 2701 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
2702 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) |
2703 | trace_print_lat_context(iter); | |
2704 | else | |
2705 | trace_print_context(iter); | |
c4a8e8be | 2706 | } |
bc0c38d1 | 2707 | |
19a7fe20 SRRH |
2708 | if (trace_seq_has_overflowed(s)) |
2709 | return TRACE_TYPE_PARTIAL_LINE; | |
2710 | ||
268ccda0 | 2711 | if (event) |
a9a57763 | 2712 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 | 2713 | |
19a7fe20 | 2714 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
02b67518 | 2715 | |
19a7fe20 | 2716 | return trace_handle_return(s); |
bc0c38d1 SR |
2717 | } |
2718 | ||
2c4f035f | 2719 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2720 | { |
2721 | struct trace_seq *s = &iter->seq; | |
2722 | struct trace_entry *entry; | |
f633cef0 | 2723 | struct trace_event *event; |
f9896bf3 IM |
2724 | |
2725 | entry = iter->ent; | |
dd0e545f | 2726 | |
19a7fe20 SRRH |
2727 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) |
2728 | trace_seq_printf(s, "%d %d %llu ", | |
2729 | entry->pid, iter->cpu, iter->ts); | |
2730 | ||
2731 | if (trace_seq_has_overflowed(s)) | |
2732 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 | 2733 | |
f633cef0 | 2734 | event = ftrace_find_event(entry->type); |
268ccda0 | 2735 | if (event) |
a9a57763 | 2736 | return event->funcs->raw(iter, 0, event); |
d9793bd8 | 2737 | |
19a7fe20 | 2738 | trace_seq_printf(s, "%d ?\n", entry->type); |
777e208d | 2739 | |
19a7fe20 | 2740 | return trace_handle_return(s); |
f9896bf3 IM |
2741 | } |
2742 | ||
2c4f035f | 2743 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2744 | { |
2745 | struct trace_seq *s = &iter->seq; | |
2746 | unsigned char newline = '\n'; | |
2747 | struct trace_entry *entry; | |
f633cef0 | 2748 | struct trace_event *event; |
5e3ca0ec IM |
2749 | |
2750 | entry = iter->ent; | |
dd0e545f | 2751 | |
c4a8e8be | 2752 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
2753 | SEQ_PUT_HEX_FIELD(s, entry->pid); |
2754 | SEQ_PUT_HEX_FIELD(s, iter->cpu); | |
2755 | SEQ_PUT_HEX_FIELD(s, iter->ts); | |
2756 | if (trace_seq_has_overflowed(s)) | |
2757 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 2758 | } |
5e3ca0ec | 2759 | |
f633cef0 | 2760 | event = ftrace_find_event(entry->type); |
268ccda0 | 2761 | if (event) { |
a9a57763 | 2762 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2763 | if (ret != TRACE_TYPE_HANDLED) |
2764 | return ret; | |
2765 | } | |
7104f300 | 2766 | |
19a7fe20 | 2767 | SEQ_PUT_FIELD(s, newline); |
5e3ca0ec | 2768 | |
19a7fe20 | 2769 | return trace_handle_return(s); |
5e3ca0ec IM |
2770 | } |
2771 | ||
2c4f035f | 2772 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2773 | { |
2774 | struct trace_seq *s = &iter->seq; | |
2775 | struct trace_entry *entry; | |
f633cef0 | 2776 | struct trace_event *event; |
cb0f12aa IM |
2777 | |
2778 | entry = iter->ent; | |
dd0e545f | 2779 | |
c4a8e8be | 2780 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
2781 | SEQ_PUT_FIELD(s, entry->pid); |
2782 | SEQ_PUT_FIELD(s, iter->cpu); | |
2783 | SEQ_PUT_FIELD(s, iter->ts); | |
2784 | if (trace_seq_has_overflowed(s)) | |
2785 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 2786 | } |
cb0f12aa | 2787 | |
f633cef0 | 2788 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2789 | return event ? event->funcs->binary(iter, 0, event) : |
2790 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2791 | } |
2792 | ||
62b915f1 | 2793 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2794 | { |
6d158a81 | 2795 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2796 | int cpu; |
2797 | ||
9aba60fe | 2798 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 2799 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 2800 | cpu = iter->cpu_file; |
6d158a81 SR |
2801 | buf_iter = trace_buffer_iter(iter, cpu); |
2802 | if (buf_iter) { | |
2803 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2804 | return 0; |
2805 | } else { | |
12883efb | 2806 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
2807 | return 0; |
2808 | } | |
2809 | return 1; | |
2810 | } | |
2811 | ||
ab46428c | 2812 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2813 | buf_iter = trace_buffer_iter(iter, cpu); |
2814 | if (buf_iter) { | |
2815 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2816 | return 0; |
2817 | } else { | |
12883efb | 2818 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
2819 | return 0; |
2820 | } | |
bc0c38d1 | 2821 | } |
d769041f | 2822 | |
797d3712 | 2823 | return 1; |
bc0c38d1 SR |
2824 | } |
2825 | ||
4f535968 | 2826 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2827 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2828 | { |
2c4f035f FW |
2829 | enum print_line_t ret; |
2830 | ||
19a7fe20 SRRH |
2831 | if (iter->lost_events) { |
2832 | trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2833 | iter->cpu, iter->lost_events); | |
2834 | if (trace_seq_has_overflowed(&iter->seq)) | |
2835 | return TRACE_TYPE_PARTIAL_LINE; | |
2836 | } | |
bc21b478 | 2837 | |
2c4f035f FW |
2838 | if (iter->trace && iter->trace->print_line) { |
2839 | ret = iter->trace->print_line(iter); | |
2840 | if (ret != TRACE_TYPE_UNHANDLED) | |
2841 | return ret; | |
2842 | } | |
72829bc3 | 2843 | |
09ae7234 SRRH |
2844 | if (iter->ent->type == TRACE_BPUTS && |
2845 | trace_flags & TRACE_ITER_PRINTK && | |
2846 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
2847 | return trace_print_bputs_msg_only(iter); | |
2848 | ||
48ead020 FW |
2849 | if (iter->ent->type == TRACE_BPRINT && |
2850 | trace_flags & TRACE_ITER_PRINTK && | |
2851 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2852 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2853 | |
66896a85 FW |
2854 | if (iter->ent->type == TRACE_PRINT && |
2855 | trace_flags & TRACE_ITER_PRINTK && | |
2856 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2857 | return trace_print_printk_msg_only(iter); |
66896a85 | 2858 | |
cb0f12aa IM |
2859 | if (trace_flags & TRACE_ITER_BIN) |
2860 | return print_bin_fmt(iter); | |
2861 | ||
5e3ca0ec IM |
2862 | if (trace_flags & TRACE_ITER_HEX) |
2863 | return print_hex_fmt(iter); | |
2864 | ||
f9896bf3 IM |
2865 | if (trace_flags & TRACE_ITER_RAW) |
2866 | return print_raw_fmt(iter); | |
2867 | ||
f9896bf3 IM |
2868 | return print_trace_fmt(iter); |
2869 | } | |
2870 | ||
7e9a49ef JO |
2871 | void trace_latency_header(struct seq_file *m) |
2872 | { | |
2873 | struct trace_iterator *iter = m->private; | |
2874 | ||
2875 | /* print nothing if the buffers are empty */ | |
2876 | if (trace_empty(iter)) | |
2877 | return; | |
2878 | ||
2879 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2880 | print_trace_header(m, iter); | |
2881 | ||
2882 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2883 | print_lat_help_header(m); | |
2884 | } | |
2885 | ||
62b915f1 JO |
2886 | void trace_default_header(struct seq_file *m) |
2887 | { | |
2888 | struct trace_iterator *iter = m->private; | |
2889 | ||
f56e7f8e JO |
2890 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2891 | return; | |
2892 | ||
62b915f1 JO |
2893 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2894 | /* print nothing if the buffers are empty */ | |
2895 | if (trace_empty(iter)) | |
2896 | return; | |
2897 | print_trace_header(m, iter); | |
2898 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2899 | print_lat_help_header(m); | |
2900 | } else { | |
77271ce4 SR |
2901 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2902 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
12883efb | 2903 | print_func_help_header_irq(iter->trace_buffer, m); |
77271ce4 | 2904 | else |
12883efb | 2905 | print_func_help_header(iter->trace_buffer, m); |
77271ce4 | 2906 | } |
62b915f1 JO |
2907 | } |
2908 | } | |
2909 | ||
e0a413f6 SR |
2910 | static void test_ftrace_alive(struct seq_file *m) |
2911 | { | |
2912 | if (!ftrace_is_dead()) | |
2913 | return; | |
d79ac28f RV |
2914 | seq_puts(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n" |
2915 | "# MAY BE MISSING FUNCTION EVENTS\n"); | |
e0a413f6 SR |
2916 | } |
2917 | ||
d8741e2e | 2918 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 2919 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 2920 | { |
d79ac28f RV |
2921 | seq_puts(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n" |
2922 | "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" | |
2923 | "# Takes a snapshot of the main buffer.\n" | |
2924 | "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n" | |
2925 | "# (Doesn't have to be '2' works with any number that\n" | |
2926 | "# is not a '0' or '1')\n"); | |
d8741e2e | 2927 | } |
f1affcaa SRRH |
2928 | |
2929 | static void show_snapshot_percpu_help(struct seq_file *m) | |
2930 | { | |
fa6f0cc7 | 2931 | seq_puts(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); |
f1affcaa | 2932 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP |
d79ac28f RV |
2933 | seq_puts(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" |
2934 | "# Takes a snapshot of the main buffer for this cpu.\n"); | |
f1affcaa | 2935 | #else |
d79ac28f RV |
2936 | seq_puts(m, "# echo 1 > snapshot : Not supported with this kernel.\n" |
2937 | "# Must use main snapshot file to allocate.\n"); | |
f1affcaa | 2938 | #endif |
d79ac28f RV |
2939 | seq_puts(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n" |
2940 | "# (Doesn't have to be '2' works with any number that\n" | |
2941 | "# is not a '0' or '1')\n"); | |
f1affcaa SRRH |
2942 | } |
2943 | ||
d8741e2e SRRH |
2944 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
2945 | { | |
45ad21ca | 2946 | if (iter->tr->allocated_snapshot) |
fa6f0cc7 | 2947 | seq_puts(m, "#\n# * Snapshot is allocated *\n#\n"); |
d8741e2e | 2948 | else |
fa6f0cc7 | 2949 | seq_puts(m, "#\n# * Snapshot is freed *\n#\n"); |
d8741e2e | 2950 | |
fa6f0cc7 | 2951 | seq_puts(m, "# Snapshot commands:\n"); |
f1affcaa SRRH |
2952 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
2953 | show_snapshot_main_help(m); | |
2954 | else | |
2955 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
2956 | } |
2957 | #else | |
2958 | /* Should never be called */ | |
2959 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
2960 | #endif | |
2961 | ||
bc0c38d1 SR |
2962 | static int s_show(struct seq_file *m, void *v) |
2963 | { | |
2964 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2965 | int ret; |
bc0c38d1 SR |
2966 | |
2967 | if (iter->ent == NULL) { | |
2968 | if (iter->tr) { | |
2969 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2970 | seq_puts(m, "#\n"); | |
e0a413f6 | 2971 | test_ftrace_alive(m); |
bc0c38d1 | 2972 | } |
d8741e2e SRRH |
2973 | if (iter->snapshot && trace_empty(iter)) |
2974 | print_snapshot_help(m, iter); | |
2975 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 2976 | iter->trace->print_header(m); |
62b915f1 JO |
2977 | else |
2978 | trace_default_header(m); | |
2979 | ||
a63ce5b3 SR |
2980 | } else if (iter->leftover) { |
2981 | /* | |
2982 | * If we filled the seq_file buffer earlier, we | |
2983 | * want to just show it now. | |
2984 | */ | |
2985 | ret = trace_print_seq(m, &iter->seq); | |
2986 | ||
2987 | /* ret should this time be zero, but you never know */ | |
2988 | iter->leftover = ret; | |
2989 | ||
bc0c38d1 | 2990 | } else { |
f9896bf3 | 2991 | print_trace_line(iter); |
a63ce5b3 SR |
2992 | ret = trace_print_seq(m, &iter->seq); |
2993 | /* | |
2994 | * If we overflow the seq_file buffer, then it will | |
2995 | * ask us for this data again at start up. | |
2996 | * Use that instead. | |
2997 | * ret is 0 if seq_file write succeeded. | |
2998 | * -1 otherwise. | |
2999 | */ | |
3000 | iter->leftover = ret; | |
bc0c38d1 SR |
3001 | } |
3002 | ||
3003 | return 0; | |
3004 | } | |
3005 | ||
649e9c70 ON |
3006 | /* |
3007 | * Should be used after trace_array_get(), trace_types_lock | |
3008 | * ensures that i_cdev was already initialized. | |
3009 | */ | |
3010 | static inline int tracing_get_cpu(struct inode *inode) | |
3011 | { | |
3012 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
3013 | return (long)inode->i_cdev - 1; | |
3014 | return RING_BUFFER_ALL_CPUS; | |
3015 | } | |
3016 | ||
88e9d34c | 3017 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
3018 | .start = s_start, |
3019 | .next = s_next, | |
3020 | .stop = s_stop, | |
3021 | .show = s_show, | |
bc0c38d1 SR |
3022 | }; |
3023 | ||
e309b41d | 3024 | static struct trace_iterator * |
6484c71c | 3025 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 3026 | { |
6484c71c | 3027 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 3028 | struct trace_iterator *iter; |
50e18b94 | 3029 | int cpu; |
bc0c38d1 | 3030 | |
85a2f9b4 SR |
3031 | if (tracing_disabled) |
3032 | return ERR_PTR(-ENODEV); | |
60a11774 | 3033 | |
50e18b94 | 3034 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
3035 | if (!iter) |
3036 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 3037 | |
6d158a81 SR |
3038 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
3039 | GFP_KERNEL); | |
93574fcc DC |
3040 | if (!iter->buffer_iter) |
3041 | goto release; | |
3042 | ||
d7350c3f FW |
3043 | /* |
3044 | * We make a copy of the current tracer to avoid concurrent | |
3045 | * changes on it while we are reading. | |
3046 | */ | |
bc0c38d1 | 3047 | mutex_lock(&trace_types_lock); |
d7350c3f | 3048 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 3049 | if (!iter->trace) |
d7350c3f | 3050 | goto fail; |
85a2f9b4 | 3051 | |
2b6080f2 | 3052 | *iter->trace = *tr->current_trace; |
d7350c3f | 3053 | |
79f55997 | 3054 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
3055 | goto fail; |
3056 | ||
12883efb SRRH |
3057 | iter->tr = tr; |
3058 | ||
3059 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
3060 | /* Currently only the top directory has a snapshot */ |
3061 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 3062 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 3063 | else |
12883efb SRRH |
3064 | #endif |
3065 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 3066 | iter->snapshot = snapshot; |
bc0c38d1 | 3067 | iter->pos = -1; |
6484c71c | 3068 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 3069 | mutex_init(&iter->mutex); |
bc0c38d1 | 3070 | |
8bba1bf5 MM |
3071 | /* Notify the tracer early; before we stop tracing. */ |
3072 | if (iter->trace && iter->trace->open) | |
a93751ca | 3073 | iter->trace->open(iter); |
8bba1bf5 | 3074 | |
12ef7d44 | 3075 | /* Annotate start of buffers if we had overruns */ |
12883efb | 3076 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
3077 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
3078 | ||
8be0709f | 3079 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 3080 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
3081 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
3082 | ||
debdd57f HT |
3083 | /* stop the trace while dumping if we are not opening "snapshot" */ |
3084 | if (!iter->snapshot) | |
2b6080f2 | 3085 | tracing_stop_tr(tr); |
2f26ebd5 | 3086 | |
ae3b5093 | 3087 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 3088 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 3089 | iter->buffer_iter[cpu] = |
12883efb | 3090 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3091 | } |
3092 | ring_buffer_read_prepare_sync(); | |
3093 | for_each_tracing_cpu(cpu) { | |
3094 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3095 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
3096 | } |
3097 | } else { | |
3098 | cpu = iter->cpu_file; | |
3928a8a2 | 3099 | iter->buffer_iter[cpu] = |
12883efb | 3100 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3101 | ring_buffer_read_prepare_sync(); |
3102 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3103 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
3104 | } |
3105 | ||
bc0c38d1 SR |
3106 | mutex_unlock(&trace_types_lock); |
3107 | ||
bc0c38d1 | 3108 | return iter; |
3928a8a2 | 3109 | |
d7350c3f | 3110 | fail: |
3928a8a2 | 3111 | mutex_unlock(&trace_types_lock); |
d7350c3f | 3112 | kfree(iter->trace); |
6d158a81 | 3113 | kfree(iter->buffer_iter); |
93574fcc | 3114 | release: |
50e18b94 JO |
3115 | seq_release_private(inode, file); |
3116 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
3117 | } |
3118 | ||
3119 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
3120 | { | |
60a11774 SR |
3121 | if (tracing_disabled) |
3122 | return -ENODEV; | |
3123 | ||
bc0c38d1 SR |
3124 | filp->private_data = inode->i_private; |
3125 | return 0; | |
3126 | } | |
3127 | ||
2e86421d GB |
3128 | bool tracing_is_disabled(void) |
3129 | { | |
3130 | return (tracing_disabled) ? true: false; | |
3131 | } | |
3132 | ||
7b85af63 SRRH |
3133 | /* |
3134 | * Open and update trace_array ref count. | |
3135 | * Must have the current trace_array passed to it. | |
3136 | */ | |
dcc30223 | 3137 | static int tracing_open_generic_tr(struct inode *inode, struct file *filp) |
7b85af63 SRRH |
3138 | { |
3139 | struct trace_array *tr = inode->i_private; | |
3140 | ||
3141 | if (tracing_disabled) | |
3142 | return -ENODEV; | |
3143 | ||
3144 | if (trace_array_get(tr) < 0) | |
3145 | return -ENODEV; | |
3146 | ||
3147 | filp->private_data = inode->i_private; | |
3148 | ||
3149 | return 0; | |
7b85af63 SRRH |
3150 | } |
3151 | ||
4fd27358 | 3152 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 3153 | { |
6484c71c | 3154 | struct trace_array *tr = inode->i_private; |
907f2784 | 3155 | struct seq_file *m = file->private_data; |
4acd4d00 | 3156 | struct trace_iterator *iter; |
3928a8a2 | 3157 | int cpu; |
bc0c38d1 | 3158 | |
ff451961 | 3159 | if (!(file->f_mode & FMODE_READ)) { |
6484c71c | 3160 | trace_array_put(tr); |
4acd4d00 | 3161 | return 0; |
ff451961 | 3162 | } |
4acd4d00 | 3163 | |
6484c71c | 3164 | /* Writes do not use seq_file */ |
4acd4d00 | 3165 | iter = m->private; |
bc0c38d1 | 3166 | mutex_lock(&trace_types_lock); |
a695cb58 | 3167 | |
3928a8a2 SR |
3168 | for_each_tracing_cpu(cpu) { |
3169 | if (iter->buffer_iter[cpu]) | |
3170 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
3171 | } | |
3172 | ||
bc0c38d1 SR |
3173 | if (iter->trace && iter->trace->close) |
3174 | iter->trace->close(iter); | |
3175 | ||
debdd57f HT |
3176 | if (!iter->snapshot) |
3177 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 3178 | tracing_start_tr(tr); |
f77d09a3 AL |
3179 | |
3180 | __trace_array_put(tr); | |
3181 | ||
bc0c38d1 SR |
3182 | mutex_unlock(&trace_types_lock); |
3183 | ||
d7350c3f | 3184 | mutex_destroy(&iter->mutex); |
b0dfa978 | 3185 | free_cpumask_var(iter->started); |
d7350c3f | 3186 | kfree(iter->trace); |
6d158a81 | 3187 | kfree(iter->buffer_iter); |
50e18b94 | 3188 | seq_release_private(inode, file); |
ff451961 | 3189 | |
bc0c38d1 SR |
3190 | return 0; |
3191 | } | |
3192 | ||
7b85af63 SRRH |
3193 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
3194 | { | |
3195 | struct trace_array *tr = inode->i_private; | |
3196 | ||
3197 | trace_array_put(tr); | |
bc0c38d1 SR |
3198 | return 0; |
3199 | } | |
3200 | ||
7b85af63 SRRH |
3201 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
3202 | { | |
3203 | struct trace_array *tr = inode->i_private; | |
3204 | ||
3205 | trace_array_put(tr); | |
3206 | ||
3207 | return single_release(inode, file); | |
3208 | } | |
3209 | ||
bc0c38d1 SR |
3210 | static int tracing_open(struct inode *inode, struct file *file) |
3211 | { | |
6484c71c | 3212 | struct trace_array *tr = inode->i_private; |
85a2f9b4 SR |
3213 | struct trace_iterator *iter; |
3214 | int ret = 0; | |
bc0c38d1 | 3215 | |
ff451961 SRRH |
3216 | if (trace_array_get(tr) < 0) |
3217 | return -ENODEV; | |
3218 | ||
4acd4d00 | 3219 | /* If this file was open for write, then erase contents */ |
6484c71c ON |
3220 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
3221 | int cpu = tracing_get_cpu(inode); | |
3222 | ||
3223 | if (cpu == RING_BUFFER_ALL_CPUS) | |
12883efb | 3224 | tracing_reset_online_cpus(&tr->trace_buffer); |
4acd4d00 | 3225 | else |
6484c71c | 3226 | tracing_reset(&tr->trace_buffer, cpu); |
4acd4d00 | 3227 | } |
bc0c38d1 | 3228 | |
4acd4d00 | 3229 | if (file->f_mode & FMODE_READ) { |
6484c71c | 3230 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
3231 | if (IS_ERR(iter)) |
3232 | ret = PTR_ERR(iter); | |
3233 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
3234 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3235 | } | |
ff451961 SRRH |
3236 | |
3237 | if (ret < 0) | |
3238 | trace_array_put(tr); | |
3239 | ||
bc0c38d1 SR |
3240 | return ret; |
3241 | } | |
3242 | ||
607e2ea1 SRRH |
3243 | /* |
3244 | * Some tracers are not suitable for instance buffers. | |
3245 | * A tracer is always available for the global array (toplevel) | |
3246 | * or if it explicitly states that it is. | |
3247 | */ | |
3248 | static bool | |
3249 | trace_ok_for_array(struct tracer *t, struct trace_array *tr) | |
3250 | { | |
3251 | return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; | |
3252 | } | |
3253 | ||
3254 | /* Find the next tracer that this trace array may use */ | |
3255 | static struct tracer * | |
3256 | get_tracer_for_array(struct trace_array *tr, struct tracer *t) | |
3257 | { | |
3258 | while (t && !trace_ok_for_array(t, tr)) | |
3259 | t = t->next; | |
3260 | ||
3261 | return t; | |
3262 | } | |
3263 | ||
e309b41d | 3264 | static void * |
bc0c38d1 SR |
3265 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3266 | { | |
607e2ea1 | 3267 | struct trace_array *tr = m->private; |
f129e965 | 3268 | struct tracer *t = v; |
bc0c38d1 SR |
3269 | |
3270 | (*pos)++; | |
3271 | ||
3272 | if (t) | |
607e2ea1 | 3273 | t = get_tracer_for_array(tr, t->next); |
bc0c38d1 | 3274 | |
bc0c38d1 SR |
3275 | return t; |
3276 | } | |
3277 | ||
3278 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3279 | { | |
607e2ea1 | 3280 | struct trace_array *tr = m->private; |
f129e965 | 3281 | struct tracer *t; |
bc0c38d1 SR |
3282 | loff_t l = 0; |
3283 | ||
3284 | mutex_lock(&trace_types_lock); | |
607e2ea1 SRRH |
3285 | |
3286 | t = get_tracer_for_array(tr, trace_types); | |
3287 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
3288 | ; | |
bc0c38d1 SR |
3289 | |
3290 | return t; | |
3291 | } | |
3292 | ||
3293 | static void t_stop(struct seq_file *m, void *p) | |
3294 | { | |
3295 | mutex_unlock(&trace_types_lock); | |
3296 | } | |
3297 | ||
3298 | static int t_show(struct seq_file *m, void *v) | |
3299 | { | |
3300 | struct tracer *t = v; | |
3301 | ||
3302 | if (!t) | |
3303 | return 0; | |
3304 | ||
fa6f0cc7 | 3305 | seq_puts(m, t->name); |
bc0c38d1 SR |
3306 | if (t->next) |
3307 | seq_putc(m, ' '); | |
3308 | else | |
3309 | seq_putc(m, '\n'); | |
3310 | ||
3311 | return 0; | |
3312 | } | |
3313 | ||
88e9d34c | 3314 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
3315 | .start = t_start, |
3316 | .next = t_next, | |
3317 | .stop = t_stop, | |
3318 | .show = t_show, | |
bc0c38d1 SR |
3319 | }; |
3320 | ||
3321 | static int show_traces_open(struct inode *inode, struct file *file) | |
3322 | { | |
607e2ea1 SRRH |
3323 | struct trace_array *tr = inode->i_private; |
3324 | struct seq_file *m; | |
3325 | int ret; | |
3326 | ||
60a11774 SR |
3327 | if (tracing_disabled) |
3328 | return -ENODEV; | |
3329 | ||
607e2ea1 SRRH |
3330 | ret = seq_open(file, &show_traces_seq_ops); |
3331 | if (ret) | |
3332 | return ret; | |
3333 | ||
3334 | m = file->private_data; | |
3335 | m->private = tr; | |
3336 | ||
3337 | return 0; | |
bc0c38d1 SR |
3338 | } |
3339 | ||
4acd4d00 SR |
3340 | static ssize_t |
3341 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
3342 | size_t count, loff_t *ppos) | |
3343 | { | |
3344 | return count; | |
3345 | } | |
3346 | ||
098c879e | 3347 | loff_t tracing_lseek(struct file *file, loff_t offset, int whence) |
364829b1 | 3348 | { |
098c879e SRRH |
3349 | int ret; |
3350 | ||
364829b1 | 3351 | if (file->f_mode & FMODE_READ) |
098c879e | 3352 | ret = seq_lseek(file, offset, whence); |
364829b1 | 3353 | else |
098c879e SRRH |
3354 | file->f_pos = ret = 0; |
3355 | ||
3356 | return ret; | |
364829b1 SP |
3357 | } |
3358 | ||
5e2336a0 | 3359 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
3360 | .open = tracing_open, |
3361 | .read = seq_read, | |
4acd4d00 | 3362 | .write = tracing_write_stub, |
098c879e | 3363 | .llseek = tracing_lseek, |
4bf39a94 | 3364 | .release = tracing_release, |
bc0c38d1 SR |
3365 | }; |
3366 | ||
5e2336a0 | 3367 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
3368 | .open = show_traces_open, |
3369 | .read = seq_read, | |
3370 | .release = seq_release, | |
b444786f | 3371 | .llseek = seq_lseek, |
c7078de1 IM |
3372 | }; |
3373 | ||
36dfe925 IM |
3374 | /* |
3375 | * The tracer itself will not take this lock, but still we want | |
3376 | * to provide a consistent cpumask to user-space: | |
3377 | */ | |
3378 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
3379 | ||
3380 | /* | |
3381 | * Temporary storage for the character representation of the | |
3382 | * CPU bitmask (and one more byte for the newline): | |
3383 | */ | |
3384 | static char mask_str[NR_CPUS + 1]; | |
3385 | ||
c7078de1 IM |
3386 | static ssize_t |
3387 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
3388 | size_t count, loff_t *ppos) | |
3389 | { | |
ccfe9e42 | 3390 | struct trace_array *tr = file_inode(filp)->i_private; |
36dfe925 | 3391 | int len; |
c7078de1 IM |
3392 | |
3393 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 3394 | |
1a40243b TH |
3395 | len = snprintf(mask_str, count, "%*pb\n", |
3396 | cpumask_pr_args(tr->tracing_cpumask)); | |
3397 | if (len >= count) { | |
36dfe925 IM |
3398 | count = -EINVAL; |
3399 | goto out_err; | |
3400 | } | |
36dfe925 IM |
3401 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); |
3402 | ||
3403 | out_err: | |
c7078de1 IM |
3404 | mutex_unlock(&tracing_cpumask_update_lock); |
3405 | ||
3406 | return count; | |
3407 | } | |
3408 | ||
3409 | static ssize_t | |
3410 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
3411 | size_t count, loff_t *ppos) | |
3412 | { | |
ccfe9e42 | 3413 | struct trace_array *tr = file_inode(filp)->i_private; |
9e01c1b7 | 3414 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 3415 | int err, cpu; |
9e01c1b7 RR |
3416 | |
3417 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
3418 | return -ENOMEM; | |
c7078de1 | 3419 | |
9e01c1b7 | 3420 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 3421 | if (err) |
36dfe925 IM |
3422 | goto err_unlock; |
3423 | ||
215368e8 LZ |
3424 | mutex_lock(&tracing_cpumask_update_lock); |
3425 | ||
a5e25883 | 3426 | local_irq_disable(); |
0b9b12c1 | 3427 | arch_spin_lock(&tr->max_lock); |
ab46428c | 3428 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
3429 | /* |
3430 | * Increase/decrease the disabled counter if we are | |
3431 | * about to flip a bit in the cpumask: | |
3432 | */ | |
ccfe9e42 | 3433 | if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3434 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3435 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3436 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 3437 | } |
ccfe9e42 | 3438 | if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3439 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3440 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3441 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
3442 | } |
3443 | } | |
0b9b12c1 | 3444 | arch_spin_unlock(&tr->max_lock); |
a5e25883 | 3445 | local_irq_enable(); |
36dfe925 | 3446 | |
ccfe9e42 | 3447 | cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
3448 | |
3449 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 3450 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
3451 | |
3452 | return count; | |
36dfe925 IM |
3453 | |
3454 | err_unlock: | |
215368e8 | 3455 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
3456 | |
3457 | return err; | |
c7078de1 IM |
3458 | } |
3459 | ||
5e2336a0 | 3460 | static const struct file_operations tracing_cpumask_fops = { |
ccfe9e42 | 3461 | .open = tracing_open_generic_tr, |
c7078de1 IM |
3462 | .read = tracing_cpumask_read, |
3463 | .write = tracing_cpumask_write, | |
ccfe9e42 | 3464 | .release = tracing_release_generic_tr, |
b444786f | 3465 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3466 | }; |
3467 | ||
fdb372ed | 3468 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 3469 | { |
d8e83d26 | 3470 | struct tracer_opt *trace_opts; |
2b6080f2 | 3471 | struct trace_array *tr = m->private; |
d8e83d26 | 3472 | u32 tracer_flags; |
d8e83d26 | 3473 | int i; |
adf9f195 | 3474 | |
d8e83d26 | 3475 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3476 | tracer_flags = tr->current_trace->flags->val; |
3477 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 3478 | |
bc0c38d1 SR |
3479 | for (i = 0; trace_options[i]; i++) { |
3480 | if (trace_flags & (1 << i)) | |
fdb372ed | 3481 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 3482 | else |
fdb372ed | 3483 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
3484 | } |
3485 | ||
adf9f195 FW |
3486 | for (i = 0; trace_opts[i].name; i++) { |
3487 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 3488 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 3489 | else |
fdb372ed | 3490 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 3491 | } |
d8e83d26 | 3492 | mutex_unlock(&trace_types_lock); |
adf9f195 | 3493 | |
fdb372ed | 3494 | return 0; |
bc0c38d1 | 3495 | } |
bc0c38d1 | 3496 | |
8c1a49ae | 3497 | static int __set_tracer_option(struct trace_array *tr, |
8d18eaaf LZ |
3498 | struct tracer_flags *tracer_flags, |
3499 | struct tracer_opt *opts, int neg) | |
3500 | { | |
8c1a49ae | 3501 | struct tracer *trace = tr->current_trace; |
8d18eaaf | 3502 | int ret; |
bc0c38d1 | 3503 | |
8c1a49ae | 3504 | ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); |
8d18eaaf LZ |
3505 | if (ret) |
3506 | return ret; | |
3507 | ||
3508 | if (neg) | |
3509 | tracer_flags->val &= ~opts->bit; | |
3510 | else | |
3511 | tracer_flags->val |= opts->bit; | |
3512 | return 0; | |
bc0c38d1 SR |
3513 | } |
3514 | ||
adf9f195 | 3515 | /* Try to assign a tracer specific option */ |
8c1a49ae | 3516 | static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) |
adf9f195 | 3517 | { |
8c1a49ae | 3518 | struct tracer *trace = tr->current_trace; |
7770841e | 3519 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 3520 | struct tracer_opt *opts = NULL; |
8d18eaaf | 3521 | int i; |
adf9f195 | 3522 | |
7770841e Z |
3523 | for (i = 0; tracer_flags->opts[i].name; i++) { |
3524 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 3525 | |
8d18eaaf | 3526 | if (strcmp(cmp, opts->name) == 0) |
8c1a49ae | 3527 | return __set_tracer_option(tr, trace->flags, opts, neg); |
adf9f195 | 3528 | } |
adf9f195 | 3529 | |
8d18eaaf | 3530 | return -EINVAL; |
adf9f195 FW |
3531 | } |
3532 | ||
613f04a0 SRRH |
3533 | /* Some tracers require overwrite to stay enabled */ |
3534 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
3535 | { | |
3536 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
3537 | return -1; | |
3538 | ||
3539 | return 0; | |
3540 | } | |
3541 | ||
2b6080f2 | 3542 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
3543 | { |
3544 | /* do nothing if flag is already set */ | |
3545 | if (!!(trace_flags & mask) == !!enabled) | |
613f04a0 SRRH |
3546 | return 0; |
3547 | ||
3548 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 | 3549 | if (tr->current_trace->flag_changed) |
bf6065b5 | 3550 | if (tr->current_trace->flag_changed(tr, mask, !!enabled)) |
613f04a0 | 3551 | return -EINVAL; |
af4617bd SR |
3552 | |
3553 | if (enabled) | |
3554 | trace_flags |= mask; | |
3555 | else | |
3556 | trace_flags &= ~mask; | |
e870e9a1 LZ |
3557 | |
3558 | if (mask == TRACE_ITER_RECORD_CMD) | |
3559 | trace_event_enable_cmd_record(enabled); | |
750912fa | 3560 | |
80902822 | 3561 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 3562 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 3563 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 3564 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
3565 | #endif |
3566 | } | |
81698831 SR |
3567 | |
3568 | if (mask == TRACE_ITER_PRINTK) | |
3569 | trace_printk_start_stop_comm(enabled); | |
613f04a0 SRRH |
3570 | |
3571 | return 0; | |
af4617bd SR |
3572 | } |
3573 | ||
2b6080f2 | 3574 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 3575 | { |
8d18eaaf | 3576 | char *cmp; |
bc0c38d1 | 3577 | int neg = 0; |
613f04a0 | 3578 | int ret = -ENODEV; |
bc0c38d1 SR |
3579 | int i; |
3580 | ||
7bcfaf54 | 3581 | cmp = strstrip(option); |
bc0c38d1 | 3582 | |
8d18eaaf | 3583 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3584 | neg = 1; |
3585 | cmp += 2; | |
3586 | } | |
3587 | ||
69d34da2 SRRH |
3588 | mutex_lock(&trace_types_lock); |
3589 | ||
bc0c38d1 | 3590 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3591 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3592 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3593 | break; |
3594 | } | |
3595 | } | |
adf9f195 FW |
3596 | |
3597 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3598 | if (!trace_options[i]) |
8c1a49ae | 3599 | ret = set_tracer_option(tr, cmp, neg); |
69d34da2 SRRH |
3600 | |
3601 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3602 | |
7bcfaf54 SR |
3603 | return ret; |
3604 | } | |
3605 | ||
3606 | static ssize_t | |
3607 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3608 | size_t cnt, loff_t *ppos) | |
3609 | { | |
2b6080f2 SR |
3610 | struct seq_file *m = filp->private_data; |
3611 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3612 | char buf[64]; |
613f04a0 | 3613 | int ret; |
7bcfaf54 SR |
3614 | |
3615 | if (cnt >= sizeof(buf)) | |
3616 | return -EINVAL; | |
3617 | ||
3618 | if (copy_from_user(&buf, ubuf, cnt)) | |
3619 | return -EFAULT; | |
3620 | ||
a8dd2176 SR |
3621 | buf[cnt] = 0; |
3622 | ||
2b6080f2 | 3623 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
3624 | if (ret < 0) |
3625 | return ret; | |
7bcfaf54 | 3626 | |
cf8517cf | 3627 | *ppos += cnt; |
bc0c38d1 SR |
3628 | |
3629 | return cnt; | |
3630 | } | |
3631 | ||
fdb372ed LZ |
3632 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
3633 | { | |
7b85af63 | 3634 | struct trace_array *tr = inode->i_private; |
f77d09a3 | 3635 | int ret; |
7b85af63 | 3636 | |
fdb372ed LZ |
3637 | if (tracing_disabled) |
3638 | return -ENODEV; | |
2b6080f2 | 3639 | |
7b85af63 SRRH |
3640 | if (trace_array_get(tr) < 0) |
3641 | return -ENODEV; | |
3642 | ||
f77d09a3 AL |
3643 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
3644 | if (ret < 0) | |
3645 | trace_array_put(tr); | |
3646 | ||
3647 | return ret; | |
fdb372ed LZ |
3648 | } |
3649 | ||
5e2336a0 | 3650 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
3651 | .open = tracing_trace_options_open, |
3652 | .read = seq_read, | |
3653 | .llseek = seq_lseek, | |
7b85af63 | 3654 | .release = tracing_single_release_tr, |
ee6bce52 | 3655 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
3656 | }; |
3657 | ||
7bd2f24c IM |
3658 | static const char readme_msg[] = |
3659 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
3660 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
3661 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
3662 | " Important files:\n" | |
3663 | " trace\t\t\t- The static contents of the buffer\n" | |
3664 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
3665 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
3666 | " current_tracer\t- function and latency tracers\n" | |
3667 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
3668 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" | |
3669 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
3670 | " trace_clock\t\t-change the clock used to order events\n" | |
3671 | " local: Per cpu clock but may not be synced across CPUs\n" | |
3672 | " global: Synced across CPUs but slows tracing down.\n" | |
3673 | " counter: Not a clock, but just an increment\n" | |
3674 | " uptime: Jiffy counter from time of boot\n" | |
3675 | " perf: Same clock that perf events use\n" | |
3676 | #ifdef CONFIG_X86_64 | |
3677 | " x86-tsc: TSC cycle counter\n" | |
3678 | #endif | |
3679 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" | |
3680 | " tracing_cpumask\t- Limit which CPUs to trace\n" | |
3681 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
3682 | "\t\t\t Remove sub-buffer with rmdir\n" | |
3683 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
71485c45 SRRH |
3684 | "\t\t\t Disable an option by adding a suffix 'no' to the\n" |
3685 | "\t\t\t option name\n" | |
939c7a4f | 3686 | " saved_cmdlines_size\t- echo command number in here to store comm-pid list\n" |
22f45649 SRRH |
3687 | #ifdef CONFIG_DYNAMIC_FTRACE |
3688 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
71485c45 SRRH |
3689 | " set_ftrace_filter\t- echo function name in here to only trace these\n" |
3690 | "\t\t\t functions\n" | |
3691 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3692 | "\t modules: Can select a group via module\n" | |
3693 | "\t Format: :mod:<module-name>\n" | |
3694 | "\t example: echo :mod:ext3 > set_ftrace_filter\n" | |
3695 | "\t triggers: a command to perform when function is hit\n" | |
3696 | "\t Format: <function>:<trigger>[:count]\n" | |
3697 | "\t trigger: traceon, traceoff\n" | |
3698 | "\t\t enable_event:<system>:<event>\n" | |
3699 | "\t\t disable_event:<system>:<event>\n" | |
22f45649 | 3700 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3701 | "\t\t stacktrace\n" |
22f45649 SRRH |
3702 | #endif |
3703 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3704 | "\t\t snapshot\n" |
22f45649 | 3705 | #endif |
17a280ea SRRH |
3706 | "\t\t dump\n" |
3707 | "\t\t cpudump\n" | |
71485c45 SRRH |
3708 | "\t example: echo do_fault:traceoff > set_ftrace_filter\n" |
3709 | "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
3710 | "\t The first one will disable tracing every time do_fault is hit\n" | |
3711 | "\t The second will disable tracing at most 3 times when do_trap is hit\n" | |
3712 | "\t The first time do trap is hit and it disables tracing, the\n" | |
3713 | "\t counter will decrement to 2. If tracing is already disabled,\n" | |
3714 | "\t the counter will not decrement. It only decrements when the\n" | |
3715 | "\t trigger did work\n" | |
3716 | "\t To remove trigger without count:\n" | |
3717 | "\t echo '!<function>:<trigger> > set_ftrace_filter\n" | |
3718 | "\t To remove trigger with a count:\n" | |
3719 | "\t echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
22f45649 | 3720 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" |
71485c45 SRRH |
3721 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" |
3722 | "\t modules: Can select a group via module command :mod:\n" | |
3723 | "\t Does not accept triggers\n" | |
22f45649 SRRH |
3724 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
3725 | #ifdef CONFIG_FUNCTION_TRACER | |
71485c45 SRRH |
3726 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" |
3727 | "\t\t (function)\n" | |
22f45649 SRRH |
3728 | #endif |
3729 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
3730 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
d048a8c7 | 3731 | " set_graph_notrace\t- Do not trace the nested calls of a function (function_graph)\n" |
22f45649 SRRH |
3732 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" |
3733 | #endif | |
3734 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 SRRH |
3735 | "\n snapshot\t\t- Like 'trace' but shows the content of the static\n" |
3736 | "\t\t\t snapshot buffer. Read the contents for more\n" | |
3737 | "\t\t\t information\n" | |
22f45649 | 3738 | #endif |
991821c8 | 3739 | #ifdef CONFIG_STACK_TRACER |
22f45649 SRRH |
3740 | " stack_trace\t\t- Shows the max stack trace when active\n" |
3741 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
71485c45 SRRH |
3742 | "\t\t\t Write into this file to reset the max size (trigger a\n" |
3743 | "\t\t\t new trace)\n" | |
22f45649 | 3744 | #ifdef CONFIG_DYNAMIC_FTRACE |
71485c45 SRRH |
3745 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n" |
3746 | "\t\t\t traces\n" | |
22f45649 | 3747 | #endif |
991821c8 | 3748 | #endif /* CONFIG_STACK_TRACER */ |
26f25564 TZ |
3749 | " events/\t\t- Directory containing all trace event subsystems:\n" |
3750 | " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" | |
3751 | " events/<system>/\t- Directory containing all trace events for <system>:\n" | |
71485c45 SRRH |
3752 | " enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n" |
3753 | "\t\t\t events\n" | |
26f25564 | 3754 | " filter\t\t- If set, only events passing filter are traced\n" |
71485c45 SRRH |
3755 | " events/<system>/<event>/\t- Directory containing control files for\n" |
3756 | "\t\t\t <event>:\n" | |
26f25564 TZ |
3757 | " enable\t\t- Write 0/1 to enable/disable tracing of <event>\n" |
3758 | " filter\t\t- If set, only events passing filter are traced\n" | |
3759 | " trigger\t\t- If set, a command to perform when event is hit\n" | |
71485c45 SRRH |
3760 | "\t Format: <trigger>[:count][if <filter>]\n" |
3761 | "\t trigger: traceon, traceoff\n" | |
3762 | "\t enable_event:<system>:<event>\n" | |
3763 | "\t disable_event:<system>:<event>\n" | |
26f25564 | 3764 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3765 | "\t\t stacktrace\n" |
26f25564 TZ |
3766 | #endif |
3767 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3768 | "\t\t snapshot\n" |
26f25564 | 3769 | #endif |
71485c45 SRRH |
3770 | "\t example: echo traceoff > events/block/block_unplug/trigger\n" |
3771 | "\t echo traceoff:3 > events/block/block_unplug/trigger\n" | |
3772 | "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" | |
3773 | "\t events/block/block_unplug/trigger\n" | |
3774 | "\t The first disables tracing every time block_unplug is hit.\n" | |
3775 | "\t The second disables tracing the first 3 times block_unplug is hit.\n" | |
3776 | "\t The third enables the kmalloc event the first 3 times block_unplug\n" | |
3777 | "\t is hit and has value of greater than 1 for the 'nr_rq' event field.\n" | |
3778 | "\t Like function triggers, the counter is only decremented if it\n" | |
3779 | "\t enabled or disabled tracing.\n" | |
3780 | "\t To remove a trigger without a count:\n" | |
3781 | "\t echo '!<trigger> > <system>/<event>/trigger\n" | |
3782 | "\t To remove a trigger with a count:\n" | |
3783 | "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" | |
3784 | "\t Filters can be ignored when removing a trigger.\n" | |
7bd2f24c IM |
3785 | ; |
3786 | ||
3787 | static ssize_t | |
3788 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
3789 | size_t cnt, loff_t *ppos) | |
3790 | { | |
3791 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
3792 | readme_msg, strlen(readme_msg)); | |
3793 | } | |
3794 | ||
5e2336a0 | 3795 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
3796 | .open = tracing_open_generic, |
3797 | .read = tracing_readme_read, | |
b444786f | 3798 | .llseek = generic_file_llseek, |
7bd2f24c IM |
3799 | }; |
3800 | ||
42584c81 YY |
3801 | static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos) |
3802 | { | |
3803 | unsigned int *ptr = v; | |
69abe6a5 | 3804 | |
42584c81 YY |
3805 | if (*pos || m->count) |
3806 | ptr++; | |
69abe6a5 | 3807 | |
42584c81 | 3808 | (*pos)++; |
69abe6a5 | 3809 | |
939c7a4f YY |
3810 | for (; ptr < &savedcmd->map_cmdline_to_pid[savedcmd->cmdline_num]; |
3811 | ptr++) { | |
42584c81 YY |
3812 | if (*ptr == -1 || *ptr == NO_CMDLINE_MAP) |
3813 | continue; | |
69abe6a5 | 3814 | |
42584c81 YY |
3815 | return ptr; |
3816 | } | |
69abe6a5 | 3817 | |
42584c81 YY |
3818 | return NULL; |
3819 | } | |
3820 | ||
3821 | static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos) | |
3822 | { | |
3823 | void *v; | |
3824 | loff_t l = 0; | |
69abe6a5 | 3825 | |
4c27e756 SRRH |
3826 | preempt_disable(); |
3827 | arch_spin_lock(&trace_cmdline_lock); | |
3828 | ||
939c7a4f | 3829 | v = &savedcmd->map_cmdline_to_pid[0]; |
42584c81 YY |
3830 | while (l <= *pos) { |
3831 | v = saved_cmdlines_next(m, v, &l); | |
3832 | if (!v) | |
3833 | return NULL; | |
69abe6a5 AP |
3834 | } |
3835 | ||
42584c81 YY |
3836 | return v; |
3837 | } | |
3838 | ||
3839 | static void saved_cmdlines_stop(struct seq_file *m, void *v) | |
3840 | { | |
4c27e756 SRRH |
3841 | arch_spin_unlock(&trace_cmdline_lock); |
3842 | preempt_enable(); | |
42584c81 | 3843 | } |
69abe6a5 | 3844 | |
42584c81 YY |
3845 | static int saved_cmdlines_show(struct seq_file *m, void *v) |
3846 | { | |
3847 | char buf[TASK_COMM_LEN]; | |
3848 | unsigned int *pid = v; | |
69abe6a5 | 3849 | |
4c27e756 | 3850 | __trace_find_cmdline(*pid, buf); |
42584c81 YY |
3851 | seq_printf(m, "%d %s\n", *pid, buf); |
3852 | return 0; | |
3853 | } | |
3854 | ||
3855 | static const struct seq_operations tracing_saved_cmdlines_seq_ops = { | |
3856 | .start = saved_cmdlines_start, | |
3857 | .next = saved_cmdlines_next, | |
3858 | .stop = saved_cmdlines_stop, | |
3859 | .show = saved_cmdlines_show, | |
3860 | }; | |
3861 | ||
3862 | static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp) | |
3863 | { | |
3864 | if (tracing_disabled) | |
3865 | return -ENODEV; | |
3866 | ||
3867 | return seq_open(filp, &tracing_saved_cmdlines_seq_ops); | |
69abe6a5 AP |
3868 | } |
3869 | ||
3870 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
42584c81 YY |
3871 | .open = tracing_saved_cmdlines_open, |
3872 | .read = seq_read, | |
3873 | .llseek = seq_lseek, | |
3874 | .release = seq_release, | |
69abe6a5 AP |
3875 | }; |
3876 | ||
939c7a4f YY |
3877 | static ssize_t |
3878 | tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf, | |
3879 | size_t cnt, loff_t *ppos) | |
3880 | { | |
3881 | char buf[64]; | |
3882 | int r; | |
3883 | ||
3884 | arch_spin_lock(&trace_cmdline_lock); | |
a6af8fbf | 3885 | r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num); |
939c7a4f YY |
3886 | arch_spin_unlock(&trace_cmdline_lock); |
3887 | ||
3888 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3889 | } | |
3890 | ||
3891 | static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s) | |
3892 | { | |
3893 | kfree(s->saved_cmdlines); | |
3894 | kfree(s->map_cmdline_to_pid); | |
3895 | kfree(s); | |
3896 | } | |
3897 | ||
3898 | static int tracing_resize_saved_cmdlines(unsigned int val) | |
3899 | { | |
3900 | struct saved_cmdlines_buffer *s, *savedcmd_temp; | |
3901 | ||
a6af8fbf | 3902 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
939c7a4f YY |
3903 | if (!s) |
3904 | return -ENOMEM; | |
3905 | ||
3906 | if (allocate_cmdlines_buffer(val, s) < 0) { | |
3907 | kfree(s); | |
3908 | return -ENOMEM; | |
3909 | } | |
3910 | ||
3911 | arch_spin_lock(&trace_cmdline_lock); | |
3912 | savedcmd_temp = savedcmd; | |
3913 | savedcmd = s; | |
3914 | arch_spin_unlock(&trace_cmdline_lock); | |
3915 | free_saved_cmdlines_buffer(savedcmd_temp); | |
3916 | ||
3917 | return 0; | |
3918 | } | |
3919 | ||
3920 | static ssize_t | |
3921 | tracing_saved_cmdlines_size_write(struct file *filp, const char __user *ubuf, | |
3922 | size_t cnt, loff_t *ppos) | |
3923 | { | |
3924 | unsigned long val; | |
3925 | int ret; | |
3926 | ||
3927 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
3928 | if (ret) | |
3929 | return ret; | |
3930 | ||
3931 | /* must have at least 1 entry or less than PID_MAX_DEFAULT */ | |
3932 | if (!val || val > PID_MAX_DEFAULT) | |
3933 | return -EINVAL; | |
3934 | ||
3935 | ret = tracing_resize_saved_cmdlines((unsigned int)val); | |
3936 | if (ret < 0) | |
3937 | return ret; | |
3938 | ||
3939 | *ppos += cnt; | |
3940 | ||
3941 | return cnt; | |
3942 | } | |
3943 | ||
3944 | static const struct file_operations tracing_saved_cmdlines_size_fops = { | |
3945 | .open = tracing_open_generic, | |
3946 | .read = tracing_saved_cmdlines_size_read, | |
3947 | .write = tracing_saved_cmdlines_size_write, | |
3948 | }; | |
3949 | ||
9828413d SRRH |
3950 | #ifdef CONFIG_TRACE_ENUM_MAP_FILE |
3951 | static union trace_enum_map_item * | |
3952 | update_enum_map(union trace_enum_map_item *ptr) | |
3953 | { | |
3954 | if (!ptr->map.enum_string) { | |
3955 | if (ptr->tail.next) { | |
3956 | ptr = ptr->tail.next; | |
3957 | /* Set ptr to the next real item (skip head) */ | |
3958 | ptr++; | |
3959 | } else | |
3960 | return NULL; | |
3961 | } | |
3962 | return ptr; | |
3963 | } | |
3964 | ||
3965 | static void *enum_map_next(struct seq_file *m, void *v, loff_t *pos) | |
3966 | { | |
3967 | union trace_enum_map_item *ptr = v; | |
3968 | ||
3969 | /* | |
3970 | * Paranoid! If ptr points to end, we don't want to increment past it. | |
3971 | * This really should never happen. | |
3972 | */ | |
3973 | ptr = update_enum_map(ptr); | |
3974 | if (WARN_ON_ONCE(!ptr)) | |
3975 | return NULL; | |
3976 | ||
3977 | ptr++; | |
3978 | ||
3979 | (*pos)++; | |
3980 | ||
3981 | ptr = update_enum_map(ptr); | |
3982 | ||
3983 | return ptr; | |
3984 | } | |
3985 | ||
3986 | static void *enum_map_start(struct seq_file *m, loff_t *pos) | |
3987 | { | |
3988 | union trace_enum_map_item *v; | |
3989 | loff_t l = 0; | |
3990 | ||
3991 | mutex_lock(&trace_enum_mutex); | |
3992 | ||
3993 | v = trace_enum_maps; | |
3994 | if (v) | |
3995 | v++; | |
3996 | ||
3997 | while (v && l < *pos) { | |
3998 | v = enum_map_next(m, v, &l); | |
3999 | } | |
4000 | ||
4001 | return v; | |
4002 | } | |
4003 | ||
4004 | static void enum_map_stop(struct seq_file *m, void *v) | |
4005 | { | |
4006 | mutex_unlock(&trace_enum_mutex); | |
4007 | } | |
4008 | ||
4009 | static int enum_map_show(struct seq_file *m, void *v) | |
4010 | { | |
4011 | union trace_enum_map_item *ptr = v; | |
4012 | ||
4013 | seq_printf(m, "%s %ld (%s)\n", | |
4014 | ptr->map.enum_string, ptr->map.enum_value, | |
4015 | ptr->map.system); | |
4016 | ||
4017 | return 0; | |
4018 | } | |
4019 | ||
4020 | static const struct seq_operations tracing_enum_map_seq_ops = { | |
4021 | .start = enum_map_start, | |
4022 | .next = enum_map_next, | |
4023 | .stop = enum_map_stop, | |
4024 | .show = enum_map_show, | |
4025 | }; | |
4026 | ||
4027 | static int tracing_enum_map_open(struct inode *inode, struct file *filp) | |
4028 | { | |
4029 | if (tracing_disabled) | |
4030 | return -ENODEV; | |
4031 | ||
4032 | return seq_open(filp, &tracing_enum_map_seq_ops); | |
4033 | } | |
4034 | ||
4035 | static const struct file_operations tracing_enum_map_fops = { | |
4036 | .open = tracing_enum_map_open, | |
4037 | .read = seq_read, | |
4038 | .llseek = seq_lseek, | |
4039 | .release = seq_release, | |
4040 | }; | |
4041 | ||
4042 | static inline union trace_enum_map_item * | |
4043 | trace_enum_jmp_to_tail(union trace_enum_map_item *ptr) | |
4044 | { | |
4045 | /* Return tail of array given the head */ | |
4046 | return ptr + ptr->head.length + 1; | |
4047 | } | |
4048 | ||
4049 | static void | |
4050 | trace_insert_enum_map_file(struct module *mod, struct trace_enum_map **start, | |
4051 | int len) | |
4052 | { | |
4053 | struct trace_enum_map **stop; | |
4054 | struct trace_enum_map **map; | |
4055 | union trace_enum_map_item *map_array; | |
4056 | union trace_enum_map_item *ptr; | |
4057 | ||
4058 | stop = start + len; | |
4059 | ||
4060 | /* | |
4061 | * The trace_enum_maps contains the map plus a head and tail item, | |
4062 | * where the head holds the module and length of array, and the | |
4063 | * tail holds a pointer to the next list. | |
4064 | */ | |
4065 | map_array = kmalloc(sizeof(*map_array) * (len + 2), GFP_KERNEL); | |
4066 | if (!map_array) { | |
4067 | pr_warning("Unable to allocate trace enum mapping\n"); | |
4068 | return; | |
4069 | } | |
4070 | ||
4071 | mutex_lock(&trace_enum_mutex); | |
4072 | ||
4073 | if (!trace_enum_maps) | |
4074 | trace_enum_maps = map_array; | |
4075 | else { | |
4076 | ptr = trace_enum_maps; | |
4077 | for (;;) { | |
4078 | ptr = trace_enum_jmp_to_tail(ptr); | |
4079 | if (!ptr->tail.next) | |
4080 | break; | |
4081 | ptr = ptr->tail.next; | |
4082 | ||
4083 | } | |
4084 | ptr->tail.next = map_array; | |
4085 | } | |
4086 | map_array->head.mod = mod; | |
4087 | map_array->head.length = len; | |
4088 | map_array++; | |
4089 | ||
4090 | for (map = start; (unsigned long)map < (unsigned long)stop; map++) { | |
4091 | map_array->map = **map; | |
4092 | map_array++; | |
4093 | } | |
4094 | memset(map_array, 0, sizeof(*map_array)); | |
4095 | ||
4096 | mutex_unlock(&trace_enum_mutex); | |
4097 | } | |
4098 | ||
4099 | static void trace_create_enum_file(struct dentry *d_tracer) | |
4100 | { | |
4101 | trace_create_file("enum_map", 0444, d_tracer, | |
4102 | NULL, &tracing_enum_map_fops); | |
4103 | } | |
4104 | ||
4105 | #else /* CONFIG_TRACE_ENUM_MAP_FILE */ | |
4106 | static inline void trace_create_enum_file(struct dentry *d_tracer) { } | |
4107 | static inline void trace_insert_enum_map_file(struct module *mod, | |
4108 | struct trace_enum_map **start, int len) { } | |
4109 | #endif /* !CONFIG_TRACE_ENUM_MAP_FILE */ | |
4110 | ||
4111 | static void trace_insert_enum_map(struct module *mod, | |
4112 | struct trace_enum_map **start, int len) | |
0c564a53 SRRH |
4113 | { |
4114 | struct trace_enum_map **map; | |
0c564a53 SRRH |
4115 | |
4116 | if (len <= 0) | |
4117 | return; | |
4118 | ||
4119 | map = start; | |
4120 | ||
4121 | trace_event_enum_update(map, len); | |
9828413d SRRH |
4122 | |
4123 | trace_insert_enum_map_file(mod, start, len); | |
0c564a53 SRRH |
4124 | } |
4125 | ||
bc0c38d1 SR |
4126 | static ssize_t |
4127 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
4128 | size_t cnt, loff_t *ppos) | |
4129 | { | |
2b6080f2 | 4130 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 4131 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
4132 | int r; |
4133 | ||
4134 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 4135 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
4136 | mutex_unlock(&trace_types_lock); |
4137 | ||
4bf39a94 | 4138 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
4139 | } |
4140 | ||
b6f11df2 ACM |
4141 | int tracer_init(struct tracer *t, struct trace_array *tr) |
4142 | { | |
12883efb | 4143 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
4144 | return t->init(tr); |
4145 | } | |
4146 | ||
12883efb | 4147 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
4148 | { |
4149 | int cpu; | |
737223fb | 4150 | |
438ced17 | 4151 | for_each_tracing_cpu(cpu) |
12883efb | 4152 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
4153 | } |
4154 | ||
12883efb | 4155 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 4156 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
4157 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
4158 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
4159 | { |
4160 | int cpu, ret = 0; | |
4161 | ||
4162 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
4163 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
4164 | ret = ring_buffer_resize(trace_buf->buffer, |
4165 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
4166 | if (ret < 0) |
4167 | break; | |
12883efb SRRH |
4168 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
4169 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
4170 | } |
4171 | } else { | |
12883efb SRRH |
4172 | ret = ring_buffer_resize(trace_buf->buffer, |
4173 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 4174 | if (ret == 0) |
12883efb SRRH |
4175 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
4176 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
4177 | } |
4178 | ||
4179 | return ret; | |
4180 | } | |
12883efb | 4181 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 4182 | |
2b6080f2 SR |
4183 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
4184 | unsigned long size, int cpu) | |
73c5162a SR |
4185 | { |
4186 | int ret; | |
4187 | ||
4188 | /* | |
4189 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
4190 | * we use the size that was given, and we can forget about |
4191 | * expanding it later. | |
73c5162a | 4192 | */ |
55034cd6 | 4193 | ring_buffer_expanded = true; |
73c5162a | 4194 | |
b382ede6 | 4195 | /* May be called before buffers are initialized */ |
12883efb | 4196 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
4197 | return 0; |
4198 | ||
12883efb | 4199 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
4200 | if (ret < 0) |
4201 | return ret; | |
4202 | ||
12883efb | 4203 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
4204 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
4205 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
4206 | goto out; |
4207 | ||
12883efb | 4208 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 4209 | if (ret < 0) { |
12883efb SRRH |
4210 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
4211 | &tr->trace_buffer, cpu); | |
73c5162a | 4212 | if (r < 0) { |
a123c52b SR |
4213 | /* |
4214 | * AARGH! We are left with different | |
4215 | * size max buffer!!!! | |
4216 | * The max buffer is our "snapshot" buffer. | |
4217 | * When a tracer needs a snapshot (one of the | |
4218 | * latency tracers), it swaps the max buffer | |
4219 | * with the saved snap shot. We succeeded to | |
4220 | * update the size of the main buffer, but failed to | |
4221 | * update the size of the max buffer. But when we tried | |
4222 | * to reset the main buffer to the original size, we | |
4223 | * failed there too. This is very unlikely to | |
4224 | * happen, but if it does, warn and kill all | |
4225 | * tracing. | |
4226 | */ | |
73c5162a SR |
4227 | WARN_ON(1); |
4228 | tracing_disabled = 1; | |
4229 | } | |
4230 | return ret; | |
4231 | } | |
4232 | ||
438ced17 | 4233 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 4234 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 4235 | else |
12883efb | 4236 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 4237 | |
ef710e10 | 4238 | out: |
12883efb SRRH |
4239 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
4240 | ||
438ced17 | 4241 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 4242 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 4243 | else |
12883efb | 4244 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
4245 | |
4246 | return ret; | |
4247 | } | |
4248 | ||
2b6080f2 SR |
4249 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
4250 | unsigned long size, int cpu_id) | |
4f271a2a | 4251 | { |
83f40318 | 4252 | int ret = size; |
4f271a2a VN |
4253 | |
4254 | mutex_lock(&trace_types_lock); | |
4255 | ||
438ced17 VN |
4256 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
4257 | /* make sure, this cpu is enabled in the mask */ | |
4258 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
4259 | ret = -EINVAL; | |
4260 | goto out; | |
4261 | } | |
4262 | } | |
4f271a2a | 4263 | |
2b6080f2 | 4264 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
4265 | if (ret < 0) |
4266 | ret = -ENOMEM; | |
4267 | ||
438ced17 | 4268 | out: |
4f271a2a VN |
4269 | mutex_unlock(&trace_types_lock); |
4270 | ||
4271 | return ret; | |
4272 | } | |
4273 | ||
ef710e10 | 4274 | |
1852fcce SR |
4275 | /** |
4276 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
4277 | * | |
4278 | * To save on memory when the tracing is never used on a system with it | |
4279 | * configured in. The ring buffers are set to a minimum size. But once | |
4280 | * a user starts to use the tracing facility, then they need to grow | |
4281 | * to their default size. | |
4282 | * | |
4283 | * This function is to be called when a tracer is about to be used. | |
4284 | */ | |
4285 | int tracing_update_buffers(void) | |
4286 | { | |
4287 | int ret = 0; | |
4288 | ||
1027fcb2 | 4289 | mutex_lock(&trace_types_lock); |
1852fcce | 4290 | if (!ring_buffer_expanded) |
2b6080f2 | 4291 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 4292 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 4293 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
4294 | |
4295 | return ret; | |
4296 | } | |
4297 | ||
577b785f SR |
4298 | struct trace_option_dentry; |
4299 | ||
4300 | static struct trace_option_dentry * | |
2b6080f2 | 4301 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f SR |
4302 | |
4303 | static void | |
4304 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
4305 | ||
6b450d25 SRRH |
4306 | /* |
4307 | * Used to clear out the tracer before deletion of an instance. | |
4308 | * Must have trace_types_lock held. | |
4309 | */ | |
4310 | static void tracing_set_nop(struct trace_array *tr) | |
4311 | { | |
4312 | if (tr->current_trace == &nop_trace) | |
4313 | return; | |
4314 | ||
50512ab5 | 4315 | tr->current_trace->enabled--; |
6b450d25 SRRH |
4316 | |
4317 | if (tr->current_trace->reset) | |
4318 | tr->current_trace->reset(tr); | |
4319 | ||
4320 | tr->current_trace = &nop_trace; | |
4321 | } | |
4322 | ||
09d23a1d | 4323 | static void update_tracer_options(struct trace_array *tr, struct tracer *t) |
bc0c38d1 | 4324 | { |
577b785f | 4325 | static struct trace_option_dentry *topts; |
09d23a1d SRRH |
4326 | |
4327 | /* Only enable if the directory has been created already. */ | |
4328 | if (!tr->dir) | |
4329 | return; | |
4330 | ||
4331 | /* Currently, only the top instance has options */ | |
4332 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL)) | |
4333 | return; | |
4334 | ||
4335 | destroy_trace_option_files(topts); | |
4336 | topts = create_trace_option_files(tr, t); | |
4337 | } | |
4338 | ||
4339 | static int tracing_set_tracer(struct trace_array *tr, const char *buf) | |
4340 | { | |
bc0c38d1 | 4341 | struct tracer *t; |
12883efb | 4342 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 4343 | bool had_max_tr; |
12883efb | 4344 | #endif |
d9e54076 | 4345 | int ret = 0; |
bc0c38d1 | 4346 | |
1027fcb2 SR |
4347 | mutex_lock(&trace_types_lock); |
4348 | ||
73c5162a | 4349 | if (!ring_buffer_expanded) { |
2b6080f2 | 4350 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 4351 | RING_BUFFER_ALL_CPUS); |
73c5162a | 4352 | if (ret < 0) |
59f586db | 4353 | goto out; |
73c5162a SR |
4354 | ret = 0; |
4355 | } | |
4356 | ||
bc0c38d1 SR |
4357 | for (t = trace_types; t; t = t->next) { |
4358 | if (strcmp(t->name, buf) == 0) | |
4359 | break; | |
4360 | } | |
c2931e05 FW |
4361 | if (!t) { |
4362 | ret = -EINVAL; | |
4363 | goto out; | |
4364 | } | |
2b6080f2 | 4365 | if (t == tr->current_trace) |
bc0c38d1 SR |
4366 | goto out; |
4367 | ||
607e2ea1 SRRH |
4368 | /* Some tracers are only allowed for the top level buffer */ |
4369 | if (!trace_ok_for_array(t, tr)) { | |
4370 | ret = -EINVAL; | |
4371 | goto out; | |
4372 | } | |
4373 | ||
cf6ab6d9 SRRH |
4374 | /* If trace pipe files are being read, we can't change the tracer */ |
4375 | if (tr->current_trace->ref) { | |
4376 | ret = -EBUSY; | |
4377 | goto out; | |
4378 | } | |
4379 | ||
9f029e83 | 4380 | trace_branch_disable(); |
613f04a0 | 4381 | |
50512ab5 | 4382 | tr->current_trace->enabled--; |
613f04a0 | 4383 | |
2b6080f2 SR |
4384 | if (tr->current_trace->reset) |
4385 | tr->current_trace->reset(tr); | |
34600f0e | 4386 | |
12883efb | 4387 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 4388 | tr->current_trace = &nop_trace; |
34600f0e | 4389 | |
45ad21ca SRRH |
4390 | #ifdef CONFIG_TRACER_MAX_TRACE |
4391 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
4392 | |
4393 | if (had_max_tr && !t->use_max_tr) { | |
4394 | /* | |
4395 | * We need to make sure that the update_max_tr sees that | |
4396 | * current_trace changed to nop_trace to keep it from | |
4397 | * swapping the buffers after we resize it. | |
4398 | * The update_max_tr is called from interrupts disabled | |
4399 | * so a synchronized_sched() is sufficient. | |
4400 | */ | |
4401 | synchronize_sched(); | |
3209cff4 | 4402 | free_snapshot(tr); |
ef710e10 | 4403 | } |
12883efb | 4404 | #endif |
09d23a1d | 4405 | update_tracer_options(tr, t); |
12883efb SRRH |
4406 | |
4407 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 4408 | if (t->use_max_tr && !had_max_tr) { |
3209cff4 | 4409 | ret = alloc_snapshot(tr); |
d60da506 HT |
4410 | if (ret < 0) |
4411 | goto out; | |
ef710e10 | 4412 | } |
12883efb | 4413 | #endif |
577b785f | 4414 | |
1c80025a | 4415 | if (t->init) { |
b6f11df2 | 4416 | ret = tracer_init(t, tr); |
1c80025a FW |
4417 | if (ret) |
4418 | goto out; | |
4419 | } | |
bc0c38d1 | 4420 | |
2b6080f2 | 4421 | tr->current_trace = t; |
50512ab5 | 4422 | tr->current_trace->enabled++; |
9f029e83 | 4423 | trace_branch_enable(tr); |
bc0c38d1 SR |
4424 | out: |
4425 | mutex_unlock(&trace_types_lock); | |
4426 | ||
d9e54076 PZ |
4427 | return ret; |
4428 | } | |
4429 | ||
4430 | static ssize_t | |
4431 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
4432 | size_t cnt, loff_t *ppos) | |
4433 | { | |
607e2ea1 | 4434 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 4435 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
4436 | int i; |
4437 | size_t ret; | |
e6e7a65a FW |
4438 | int err; |
4439 | ||
4440 | ret = cnt; | |
d9e54076 | 4441 | |
ee6c2c1b LZ |
4442 | if (cnt > MAX_TRACER_SIZE) |
4443 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
4444 | |
4445 | if (copy_from_user(&buf, ubuf, cnt)) | |
4446 | return -EFAULT; | |
4447 | ||
4448 | buf[cnt] = 0; | |
4449 | ||
4450 | /* strip ending whitespace. */ | |
4451 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
4452 | buf[i] = 0; | |
4453 | ||
607e2ea1 | 4454 | err = tracing_set_tracer(tr, buf); |
e6e7a65a FW |
4455 | if (err) |
4456 | return err; | |
d9e54076 | 4457 | |
cf8517cf | 4458 | *ppos += ret; |
bc0c38d1 | 4459 | |
c2931e05 | 4460 | return ret; |
bc0c38d1 SR |
4461 | } |
4462 | ||
4463 | static ssize_t | |
6508fa76 SF |
4464 | tracing_nsecs_read(unsigned long *ptr, char __user *ubuf, |
4465 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 4466 | { |
bc0c38d1 SR |
4467 | char buf[64]; |
4468 | int r; | |
4469 | ||
cffae437 | 4470 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 4471 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
4472 | if (r > sizeof(buf)) |
4473 | r = sizeof(buf); | |
4bf39a94 | 4474 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
4475 | } |
4476 | ||
4477 | static ssize_t | |
6508fa76 SF |
4478 | tracing_nsecs_write(unsigned long *ptr, const char __user *ubuf, |
4479 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 4480 | { |
5e39841c | 4481 | unsigned long val; |
c6caeeb1 | 4482 | int ret; |
bc0c38d1 | 4483 | |
22fe9b54 PH |
4484 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4485 | if (ret) | |
c6caeeb1 | 4486 | return ret; |
bc0c38d1 SR |
4487 | |
4488 | *ptr = val * 1000; | |
4489 | ||
4490 | return cnt; | |
4491 | } | |
4492 | ||
6508fa76 SF |
4493 | static ssize_t |
4494 | tracing_thresh_read(struct file *filp, char __user *ubuf, | |
4495 | size_t cnt, loff_t *ppos) | |
4496 | { | |
4497 | return tracing_nsecs_read(&tracing_thresh, ubuf, cnt, ppos); | |
4498 | } | |
4499 | ||
4500 | static ssize_t | |
4501 | tracing_thresh_write(struct file *filp, const char __user *ubuf, | |
4502 | size_t cnt, loff_t *ppos) | |
4503 | { | |
4504 | struct trace_array *tr = filp->private_data; | |
4505 | int ret; | |
4506 | ||
4507 | mutex_lock(&trace_types_lock); | |
4508 | ret = tracing_nsecs_write(&tracing_thresh, ubuf, cnt, ppos); | |
4509 | if (ret < 0) | |
4510 | goto out; | |
4511 | ||
4512 | if (tr->current_trace->update_thresh) { | |
4513 | ret = tr->current_trace->update_thresh(tr); | |
4514 | if (ret < 0) | |
4515 | goto out; | |
4516 | } | |
4517 | ||
4518 | ret = cnt; | |
4519 | out: | |
4520 | mutex_unlock(&trace_types_lock); | |
4521 | ||
4522 | return ret; | |
4523 | } | |
4524 | ||
4525 | static ssize_t | |
4526 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
4527 | size_t cnt, loff_t *ppos) | |
4528 | { | |
4529 | return tracing_nsecs_read(filp->private_data, ubuf, cnt, ppos); | |
4530 | } | |
4531 | ||
4532 | static ssize_t | |
4533 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
4534 | size_t cnt, loff_t *ppos) | |
4535 | { | |
4536 | return tracing_nsecs_write(filp->private_data, ubuf, cnt, ppos); | |
4537 | } | |
4538 | ||
b3806b43 SR |
4539 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
4540 | { | |
15544209 | 4541 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4542 | struct trace_iterator *iter; |
b04cc6b1 | 4543 | int ret = 0; |
b3806b43 SR |
4544 | |
4545 | if (tracing_disabled) | |
4546 | return -ENODEV; | |
4547 | ||
7b85af63 SRRH |
4548 | if (trace_array_get(tr) < 0) |
4549 | return -ENODEV; | |
4550 | ||
b04cc6b1 FW |
4551 | mutex_lock(&trace_types_lock); |
4552 | ||
b3806b43 SR |
4553 | /* create a buffer to store the information to pass to userspace */ |
4554 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
4555 | if (!iter) { |
4556 | ret = -ENOMEM; | |
f77d09a3 | 4557 | __trace_array_put(tr); |
b04cc6b1 FW |
4558 | goto out; |
4559 | } | |
b3806b43 | 4560 | |
3a161d99 | 4561 | trace_seq_init(&iter->seq); |
d716ff71 | 4562 | iter->trace = tr->current_trace; |
d7350c3f | 4563 | |
4462344e | 4564 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 4565 | ret = -ENOMEM; |
d7350c3f | 4566 | goto fail; |
4462344e RR |
4567 | } |
4568 | ||
a309720c | 4569 | /* trace pipe does not show start of buffer */ |
4462344e | 4570 | cpumask_setall(iter->started); |
a309720c | 4571 | |
112f38a7 SR |
4572 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
4573 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
4574 | ||
8be0709f | 4575 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 4576 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
4577 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
4578 | ||
15544209 ON |
4579 | iter->tr = tr; |
4580 | iter->trace_buffer = &tr->trace_buffer; | |
4581 | iter->cpu_file = tracing_get_cpu(inode); | |
d7350c3f | 4582 | mutex_init(&iter->mutex); |
b3806b43 SR |
4583 | filp->private_data = iter; |
4584 | ||
107bad8b SR |
4585 | if (iter->trace->pipe_open) |
4586 | iter->trace->pipe_open(iter); | |
107bad8b | 4587 | |
b444786f | 4588 | nonseekable_open(inode, filp); |
cf6ab6d9 SRRH |
4589 | |
4590 | tr->current_trace->ref++; | |
b04cc6b1 FW |
4591 | out: |
4592 | mutex_unlock(&trace_types_lock); | |
4593 | return ret; | |
d7350c3f FW |
4594 | |
4595 | fail: | |
4596 | kfree(iter->trace); | |
4597 | kfree(iter); | |
7b85af63 | 4598 | __trace_array_put(tr); |
d7350c3f FW |
4599 | mutex_unlock(&trace_types_lock); |
4600 | return ret; | |
b3806b43 SR |
4601 | } |
4602 | ||
4603 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
4604 | { | |
4605 | struct trace_iterator *iter = file->private_data; | |
15544209 | 4606 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4607 | |
b04cc6b1 FW |
4608 | mutex_lock(&trace_types_lock); |
4609 | ||
cf6ab6d9 SRRH |
4610 | tr->current_trace->ref--; |
4611 | ||
29bf4a5e | 4612 | if (iter->trace->pipe_close) |
c521efd1 SR |
4613 | iter->trace->pipe_close(iter); |
4614 | ||
b04cc6b1 FW |
4615 | mutex_unlock(&trace_types_lock); |
4616 | ||
4462344e | 4617 | free_cpumask_var(iter->started); |
d7350c3f | 4618 | mutex_destroy(&iter->mutex); |
b3806b43 | 4619 | kfree(iter); |
b3806b43 | 4620 | |
7b85af63 SRRH |
4621 | trace_array_put(tr); |
4622 | ||
b3806b43 SR |
4623 | return 0; |
4624 | } | |
4625 | ||
2a2cc8f7 | 4626 | static unsigned int |
cc60cdc9 | 4627 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 4628 | { |
15693458 SRRH |
4629 | /* Iterators are static, they should be filled or empty */ |
4630 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
4631 | return POLLIN | POLLRDNORM; | |
2a2cc8f7 | 4632 | |
15693458 | 4633 | if (trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
4634 | /* |
4635 | * Always select as readable when in blocking mode | |
4636 | */ | |
4637 | return POLLIN | POLLRDNORM; | |
15693458 | 4638 | else |
12883efb | 4639 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 4640 | filp, poll_table); |
2a2cc8f7 | 4641 | } |
2a2cc8f7 | 4642 | |
cc60cdc9 SR |
4643 | static unsigned int |
4644 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
4645 | { | |
4646 | struct trace_iterator *iter = filp->private_data; | |
4647 | ||
4648 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
4649 | } |
4650 | ||
d716ff71 | 4651 | /* Must be called with iter->mutex held. */ |
ff98781b | 4652 | static int tracing_wait_pipe(struct file *filp) |
b3806b43 SR |
4653 | { |
4654 | struct trace_iterator *iter = filp->private_data; | |
8b8b3683 | 4655 | int ret; |
b3806b43 | 4656 | |
b3806b43 | 4657 | while (trace_empty(iter)) { |
2dc8f095 | 4658 | |
107bad8b | 4659 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 4660 | return -EAGAIN; |
107bad8b | 4661 | } |
2dc8f095 | 4662 | |
b3806b43 | 4663 | /* |
250bfd3d | 4664 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
4665 | * We still block if tracing is disabled, but we have never |
4666 | * read anything. This allows a user to cat this file, and | |
4667 | * then enable tracing. But after we have read something, | |
4668 | * we give an EOF when tracing is again disabled. | |
4669 | * | |
4670 | * iter->pos will be 0 if we haven't read anything. | |
4671 | */ | |
10246fa3 | 4672 | if (!tracing_is_on() && iter->pos) |
b3806b43 | 4673 | break; |
f4874261 SRRH |
4674 | |
4675 | mutex_unlock(&iter->mutex); | |
4676 | ||
e30f53aa | 4677 | ret = wait_on_pipe(iter, false); |
f4874261 SRRH |
4678 | |
4679 | mutex_lock(&iter->mutex); | |
4680 | ||
8b8b3683 SRRH |
4681 | if (ret) |
4682 | return ret; | |
b3806b43 SR |
4683 | } |
4684 | ||
ff98781b EGM |
4685 | return 1; |
4686 | } | |
4687 | ||
4688 | /* | |
4689 | * Consumer reader. | |
4690 | */ | |
4691 | static ssize_t | |
4692 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
4693 | size_t cnt, loff_t *ppos) | |
4694 | { | |
4695 | struct trace_iterator *iter = filp->private_data; | |
4696 | ssize_t sret; | |
4697 | ||
4698 | /* return any leftover data */ | |
4699 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
4700 | if (sret != -EBUSY) | |
4701 | return sret; | |
4702 | ||
f9520750 | 4703 | trace_seq_init(&iter->seq); |
ff98781b | 4704 | |
d7350c3f FW |
4705 | /* |
4706 | * Avoid more than one consumer on a single file descriptor | |
4707 | * This is just a matter of traces coherency, the ring buffer itself | |
4708 | * is protected. | |
4709 | */ | |
4710 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
4711 | if (iter->trace->read) { |
4712 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
4713 | if (sret) | |
4714 | goto out; | |
4715 | } | |
4716 | ||
4717 | waitagain: | |
4718 | sret = tracing_wait_pipe(filp); | |
4719 | if (sret <= 0) | |
4720 | goto out; | |
4721 | ||
b3806b43 | 4722 | /* stop when tracing is finished */ |
ff98781b EGM |
4723 | if (trace_empty(iter)) { |
4724 | sret = 0; | |
107bad8b | 4725 | goto out; |
ff98781b | 4726 | } |
b3806b43 SR |
4727 | |
4728 | if (cnt >= PAGE_SIZE) | |
4729 | cnt = PAGE_SIZE - 1; | |
4730 | ||
53d0aa77 | 4731 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
4732 | memset(&iter->seq, 0, |
4733 | sizeof(struct trace_iterator) - | |
4734 | offsetof(struct trace_iterator, seq)); | |
ed5467da | 4735 | cpumask_clear(iter->started); |
4823ed7e | 4736 | iter->pos = -1; |
b3806b43 | 4737 | |
4f535968 | 4738 | trace_event_read_lock(); |
7e53bd42 | 4739 | trace_access_lock(iter->cpu_file); |
955b61e5 | 4740 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 4741 | enum print_line_t ret; |
5ac48378 | 4742 | int save_len = iter->seq.seq.len; |
088b1e42 | 4743 | |
f9896bf3 | 4744 | ret = print_trace_line(iter); |
2c4f035f | 4745 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 | 4746 | /* don't print partial lines */ |
5ac48378 | 4747 | iter->seq.seq.len = save_len; |
b3806b43 | 4748 | break; |
088b1e42 | 4749 | } |
b91facc3 FW |
4750 | if (ret != TRACE_TYPE_NO_CONSUME) |
4751 | trace_consume(iter); | |
b3806b43 | 4752 | |
5ac48378 | 4753 | if (trace_seq_used(&iter->seq) >= cnt) |
b3806b43 | 4754 | break; |
ee5e51f5 JO |
4755 | |
4756 | /* | |
4757 | * Setting the full flag means we reached the trace_seq buffer | |
4758 | * size and we should leave by partial output condition above. | |
4759 | * One of the trace_seq_* functions is not used properly. | |
4760 | */ | |
4761 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
4762 | iter->ent->type); | |
b3806b43 | 4763 | } |
7e53bd42 | 4764 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4765 | trace_event_read_unlock(); |
b3806b43 | 4766 | |
b3806b43 | 4767 | /* Now copy what we have to the user */ |
6c6c2796 | 4768 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
5ac48378 | 4769 | if (iter->seq.seq.readpos >= trace_seq_used(&iter->seq)) |
f9520750 | 4770 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
4771 | |
4772 | /* | |
25985edc | 4773 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
4774 | * entries, go back to wait for more entries. |
4775 | */ | |
6c6c2796 | 4776 | if (sret == -EBUSY) |
9ff4b974 | 4777 | goto waitagain; |
b3806b43 | 4778 | |
107bad8b | 4779 | out: |
d7350c3f | 4780 | mutex_unlock(&iter->mutex); |
107bad8b | 4781 | |
6c6c2796 | 4782 | return sret; |
b3806b43 SR |
4783 | } |
4784 | ||
3c56819b EGM |
4785 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, |
4786 | unsigned int idx) | |
4787 | { | |
4788 | __free_page(spd->pages[idx]); | |
4789 | } | |
4790 | ||
28dfef8f | 4791 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 | 4792 | .can_merge = 0, |
34cd4998 | 4793 | .confirm = generic_pipe_buf_confirm, |
92fdd98c | 4794 | .release = generic_pipe_buf_release, |
34cd4998 SR |
4795 | .steal = generic_pipe_buf_steal, |
4796 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
4797 | }; |
4798 | ||
34cd4998 | 4799 | static size_t |
fa7c7f6e | 4800 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
4801 | { |
4802 | size_t count; | |
74f06bb7 | 4803 | int save_len; |
34cd4998 SR |
4804 | int ret; |
4805 | ||
4806 | /* Seq buffer is page-sized, exactly what we need. */ | |
4807 | for (;;) { | |
74f06bb7 | 4808 | save_len = iter->seq.seq.len; |
34cd4998 | 4809 | ret = print_trace_line(iter); |
74f06bb7 SRRH |
4810 | |
4811 | if (trace_seq_has_overflowed(&iter->seq)) { | |
4812 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
4813 | break; |
4814 | } | |
74f06bb7 SRRH |
4815 | |
4816 | /* | |
4817 | * This should not be hit, because it should only | |
4818 | * be set if the iter->seq overflowed. But check it | |
4819 | * anyway to be safe. | |
4820 | */ | |
34cd4998 | 4821 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
74f06bb7 SRRH |
4822 | iter->seq.seq.len = save_len; |
4823 | break; | |
4824 | } | |
4825 | ||
5ac48378 | 4826 | count = trace_seq_used(&iter->seq) - save_len; |
74f06bb7 SRRH |
4827 | if (rem < count) { |
4828 | rem = 0; | |
4829 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
4830 | break; |
4831 | } | |
4832 | ||
74e7ff8c LJ |
4833 | if (ret != TRACE_TYPE_NO_CONSUME) |
4834 | trace_consume(iter); | |
34cd4998 | 4835 | rem -= count; |
955b61e5 | 4836 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
4837 | rem = 0; |
4838 | iter->ent = NULL; | |
4839 | break; | |
4840 | } | |
4841 | } | |
4842 | ||
4843 | return rem; | |
4844 | } | |
4845 | ||
3c56819b EGM |
4846 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
4847 | loff_t *ppos, | |
4848 | struct pipe_inode_info *pipe, | |
4849 | size_t len, | |
4850 | unsigned int flags) | |
4851 | { | |
35f3d14d JA |
4852 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
4853 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
4854 | struct trace_iterator *iter = filp->private_data; |
4855 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
4856 | .pages = pages_def, |
4857 | .partial = partial_def, | |
34cd4998 | 4858 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 4859 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
4860 | .flags = flags, |
4861 | .ops = &tracing_pipe_buf_ops, | |
4862 | .spd_release = tracing_spd_release_pipe, | |
3c56819b EGM |
4863 | }; |
4864 | ssize_t ret; | |
34cd4998 | 4865 | size_t rem; |
3c56819b EGM |
4866 | unsigned int i; |
4867 | ||
35f3d14d JA |
4868 | if (splice_grow_spd(pipe, &spd)) |
4869 | return -ENOMEM; | |
4870 | ||
d7350c3f | 4871 | mutex_lock(&iter->mutex); |
3c56819b EGM |
4872 | |
4873 | if (iter->trace->splice_read) { | |
4874 | ret = iter->trace->splice_read(iter, filp, | |
4875 | ppos, pipe, len, flags); | |
4876 | if (ret) | |
34cd4998 | 4877 | goto out_err; |
3c56819b EGM |
4878 | } |
4879 | ||
4880 | ret = tracing_wait_pipe(filp); | |
4881 | if (ret <= 0) | |
34cd4998 | 4882 | goto out_err; |
3c56819b | 4883 | |
955b61e5 | 4884 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 4885 | ret = -EFAULT; |
34cd4998 | 4886 | goto out_err; |
3c56819b EGM |
4887 | } |
4888 | ||
4f535968 | 4889 | trace_event_read_lock(); |
7e53bd42 | 4890 | trace_access_lock(iter->cpu_file); |
4f535968 | 4891 | |
3c56819b | 4892 | /* Fill as many pages as possible. */ |
a786c06d | 4893 | for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) { |
35f3d14d JA |
4894 | spd.pages[i] = alloc_page(GFP_KERNEL); |
4895 | if (!spd.pages[i]) | |
34cd4998 | 4896 | break; |
3c56819b | 4897 | |
fa7c7f6e | 4898 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
4899 | |
4900 | /* Copy the data into the page, so we can start over. */ | |
4901 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 4902 | page_address(spd.pages[i]), |
5ac48378 | 4903 | trace_seq_used(&iter->seq)); |
3c56819b | 4904 | if (ret < 0) { |
35f3d14d | 4905 | __free_page(spd.pages[i]); |
3c56819b EGM |
4906 | break; |
4907 | } | |
35f3d14d | 4908 | spd.partial[i].offset = 0; |
5ac48378 | 4909 | spd.partial[i].len = trace_seq_used(&iter->seq); |
3c56819b | 4910 | |
f9520750 | 4911 | trace_seq_init(&iter->seq); |
3c56819b EGM |
4912 | } |
4913 | ||
7e53bd42 | 4914 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4915 | trace_event_read_unlock(); |
d7350c3f | 4916 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
4917 | |
4918 | spd.nr_pages = i; | |
4919 | ||
35f3d14d JA |
4920 | ret = splice_to_pipe(pipe, &spd); |
4921 | out: | |
047fe360 | 4922 | splice_shrink_spd(&spd); |
35f3d14d | 4923 | return ret; |
3c56819b | 4924 | |
34cd4998 | 4925 | out_err: |
d7350c3f | 4926 | mutex_unlock(&iter->mutex); |
35f3d14d | 4927 | goto out; |
3c56819b EGM |
4928 | } |
4929 | ||
a98a3c3f SR |
4930 | static ssize_t |
4931 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
4932 | size_t cnt, loff_t *ppos) | |
4933 | { | |
0bc392ee ON |
4934 | struct inode *inode = file_inode(filp); |
4935 | struct trace_array *tr = inode->i_private; | |
4936 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
4937 | char buf[64]; |
4938 | int r = 0; | |
4939 | ssize_t ret; | |
a98a3c3f | 4940 | |
db526ca3 | 4941 | mutex_lock(&trace_types_lock); |
438ced17 | 4942 | |
0bc392ee | 4943 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
4944 | int cpu, buf_size_same; |
4945 | unsigned long size; | |
4946 | ||
4947 | size = 0; | |
4948 | buf_size_same = 1; | |
4949 | /* check if all cpu sizes are same */ | |
4950 | for_each_tracing_cpu(cpu) { | |
4951 | /* fill in the size from first enabled cpu */ | |
4952 | if (size == 0) | |
12883efb SRRH |
4953 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
4954 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
4955 | buf_size_same = 0; |
4956 | break; | |
4957 | } | |
4958 | } | |
4959 | ||
4960 | if (buf_size_same) { | |
4961 | if (!ring_buffer_expanded) | |
4962 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
4963 | size >> 10, | |
4964 | trace_buf_size >> 10); | |
4965 | else | |
4966 | r = sprintf(buf, "%lu\n", size >> 10); | |
4967 | } else | |
4968 | r = sprintf(buf, "X\n"); | |
4969 | } else | |
0bc392ee | 4970 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10); |
438ced17 | 4971 | |
db526ca3 SR |
4972 | mutex_unlock(&trace_types_lock); |
4973 | ||
438ced17 VN |
4974 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
4975 | return ret; | |
a98a3c3f SR |
4976 | } |
4977 | ||
4978 | static ssize_t | |
4979 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
4980 | size_t cnt, loff_t *ppos) | |
4981 | { | |
0bc392ee ON |
4982 | struct inode *inode = file_inode(filp); |
4983 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 4984 | unsigned long val; |
4f271a2a | 4985 | int ret; |
a98a3c3f | 4986 | |
22fe9b54 PH |
4987 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4988 | if (ret) | |
c6caeeb1 | 4989 | return ret; |
a98a3c3f SR |
4990 | |
4991 | /* must have at least 1 entry */ | |
4992 | if (!val) | |
4993 | return -EINVAL; | |
4994 | ||
1696b2b0 SR |
4995 | /* value is in KB */ |
4996 | val <<= 10; | |
0bc392ee | 4997 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
4998 | if (ret < 0) |
4999 | return ret; | |
a98a3c3f | 5000 | |
cf8517cf | 5001 | *ppos += cnt; |
a98a3c3f | 5002 | |
4f271a2a VN |
5003 | return cnt; |
5004 | } | |
bf5e6519 | 5005 | |
f81ab074 VN |
5006 | static ssize_t |
5007 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
5008 | size_t cnt, loff_t *ppos) | |
5009 | { | |
5010 | struct trace_array *tr = filp->private_data; | |
5011 | char buf[64]; | |
5012 | int r, cpu; | |
5013 | unsigned long size = 0, expanded_size = 0; | |
5014 | ||
5015 | mutex_lock(&trace_types_lock); | |
5016 | for_each_tracing_cpu(cpu) { | |
12883efb | 5017 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
5018 | if (!ring_buffer_expanded) |
5019 | expanded_size += trace_buf_size >> 10; | |
5020 | } | |
5021 | if (ring_buffer_expanded) | |
5022 | r = sprintf(buf, "%lu\n", size); | |
5023 | else | |
5024 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
5025 | mutex_unlock(&trace_types_lock); | |
5026 | ||
5027 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5028 | } | |
5029 | ||
4f271a2a VN |
5030 | static ssize_t |
5031 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
5032 | size_t cnt, loff_t *ppos) | |
5033 | { | |
5034 | /* | |
5035 | * There is no need to read what the user has written, this function | |
5036 | * is just to make sure that there is no error when "echo" is used | |
5037 | */ | |
5038 | ||
5039 | *ppos += cnt; | |
a98a3c3f SR |
5040 | |
5041 | return cnt; | |
5042 | } | |
5043 | ||
4f271a2a VN |
5044 | static int |
5045 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
5046 | { | |
2b6080f2 SR |
5047 | struct trace_array *tr = inode->i_private; |
5048 | ||
cf30cf67 SR |
5049 | /* disable tracing ? */ |
5050 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
711e1243 | 5051 | tracer_tracing_off(tr); |
4f271a2a | 5052 | /* resize the ring buffer to 0 */ |
2b6080f2 | 5053 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 5054 | |
7b85af63 SRRH |
5055 | trace_array_put(tr); |
5056 | ||
4f271a2a VN |
5057 | return 0; |
5058 | } | |
5059 | ||
5bf9a1ee PP |
5060 | static ssize_t |
5061 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
5062 | size_t cnt, loff_t *fpos) | |
5063 | { | |
d696b58c | 5064 | unsigned long addr = (unsigned long)ubuf; |
2d71619c | 5065 | struct trace_array *tr = filp->private_data; |
d696b58c SR |
5066 | struct ring_buffer_event *event; |
5067 | struct ring_buffer *buffer; | |
5068 | struct print_entry *entry; | |
5069 | unsigned long irq_flags; | |
5070 | struct page *pages[2]; | |
6edb2a8a | 5071 | void *map_page[2]; |
d696b58c SR |
5072 | int nr_pages = 1; |
5073 | ssize_t written; | |
d696b58c SR |
5074 | int offset; |
5075 | int size; | |
5076 | int len; | |
5077 | int ret; | |
6edb2a8a | 5078 | int i; |
5bf9a1ee | 5079 | |
c76f0694 | 5080 | if (tracing_disabled) |
5bf9a1ee PP |
5081 | return -EINVAL; |
5082 | ||
5224c3a3 MSB |
5083 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
5084 | return -EINVAL; | |
5085 | ||
5bf9a1ee PP |
5086 | if (cnt > TRACE_BUF_SIZE) |
5087 | cnt = TRACE_BUF_SIZE; | |
5088 | ||
d696b58c SR |
5089 | /* |
5090 | * Userspace is injecting traces into the kernel trace buffer. | |
5091 | * We want to be as non intrusive as possible. | |
5092 | * To do so, we do not want to allocate any special buffers | |
5093 | * or take any locks, but instead write the userspace data | |
5094 | * straight into the ring buffer. | |
5095 | * | |
5096 | * First we need to pin the userspace buffer into memory, | |
5097 | * which, most likely it is, because it just referenced it. | |
5098 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
5099 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
5100 | * pages directly. We then write the data directly into the | |
5101 | * ring buffer. | |
5102 | */ | |
5103 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 5104 | |
d696b58c SR |
5105 | /* check if we cross pages */ |
5106 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
5107 | nr_pages = 2; | |
5108 | ||
5109 | offset = addr & (PAGE_SIZE - 1); | |
5110 | addr &= PAGE_MASK; | |
5111 | ||
5112 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
5113 | if (ret < nr_pages) { | |
5114 | while (--ret >= 0) | |
5115 | put_page(pages[ret]); | |
5116 | written = -EFAULT; | |
5117 | goto out; | |
5bf9a1ee | 5118 | } |
d696b58c | 5119 | |
6edb2a8a SR |
5120 | for (i = 0; i < nr_pages; i++) |
5121 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
5122 | |
5123 | local_save_flags(irq_flags); | |
5124 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
2d71619c | 5125 | buffer = tr->trace_buffer.buffer; |
d696b58c SR |
5126 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
5127 | irq_flags, preempt_count()); | |
5128 | if (!event) { | |
5129 | /* Ring buffer disabled, return as if not open for write */ | |
5130 | written = -EBADF; | |
5131 | goto out_unlock; | |
5bf9a1ee | 5132 | } |
d696b58c SR |
5133 | |
5134 | entry = ring_buffer_event_data(event); | |
5135 | entry->ip = _THIS_IP_; | |
5136 | ||
5137 | if (nr_pages == 2) { | |
5138 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
5139 | memcpy(&entry->buf, map_page[0] + offset, len); |
5140 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 5141 | } else |
6edb2a8a | 5142 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 5143 | |
d696b58c SR |
5144 | if (entry->buf[cnt - 1] != '\n') { |
5145 | entry->buf[cnt] = '\n'; | |
5146 | entry->buf[cnt + 1] = '\0'; | |
5147 | } else | |
5148 | entry->buf[cnt] = '\0'; | |
5149 | ||
7ffbd48d | 5150 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 5151 | |
d696b58c | 5152 | written = cnt; |
5bf9a1ee | 5153 | |
d696b58c | 5154 | *fpos += written; |
1aa54bca | 5155 | |
d696b58c | 5156 | out_unlock: |
7215853e | 5157 | for (i = nr_pages - 1; i >= 0; i--) { |
6edb2a8a SR |
5158 | kunmap_atomic(map_page[i]); |
5159 | put_page(pages[i]); | |
5160 | } | |
d696b58c | 5161 | out: |
1aa54bca | 5162 | return written; |
5bf9a1ee PP |
5163 | } |
5164 | ||
13f16d20 | 5165 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 5166 | { |
2b6080f2 | 5167 | struct trace_array *tr = m->private; |
5079f326 Z |
5168 | int i; |
5169 | ||
5170 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 5171 | seq_printf(m, |
5079f326 | 5172 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
5173 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
5174 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 5175 | seq_putc(m, '\n'); |
5079f326 | 5176 | |
13f16d20 | 5177 | return 0; |
5079f326 Z |
5178 | } |
5179 | ||
e1e232ca | 5180 | static int tracing_set_clock(struct trace_array *tr, const char *clockstr) |
5079f326 | 5181 | { |
5079f326 Z |
5182 | int i; |
5183 | ||
5079f326 Z |
5184 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { |
5185 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
5186 | break; | |
5187 | } | |
5188 | if (i == ARRAY_SIZE(trace_clocks)) | |
5189 | return -EINVAL; | |
5190 | ||
5079f326 Z |
5191 | mutex_lock(&trace_types_lock); |
5192 | ||
2b6080f2 SR |
5193 | tr->clock_id = i; |
5194 | ||
12883efb | 5195 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 5196 | |
60303ed3 DS |
5197 | /* |
5198 | * New clock may not be consistent with the previous clock. | |
5199 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
5200 | */ | |
9457158b | 5201 | tracing_reset_online_cpus(&tr->trace_buffer); |
12883efb SRRH |
5202 | |
5203 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5204 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) | |
5205 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); | |
9457158b | 5206 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 5207 | #endif |
60303ed3 | 5208 | |
5079f326 Z |
5209 | mutex_unlock(&trace_types_lock); |
5210 | ||
e1e232ca SR |
5211 | return 0; |
5212 | } | |
5213 | ||
5214 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
5215 | size_t cnt, loff_t *fpos) | |
5216 | { | |
5217 | struct seq_file *m = filp->private_data; | |
5218 | struct trace_array *tr = m->private; | |
5219 | char buf[64]; | |
5220 | const char *clockstr; | |
5221 | int ret; | |
5222 | ||
5223 | if (cnt >= sizeof(buf)) | |
5224 | return -EINVAL; | |
5225 | ||
5226 | if (copy_from_user(&buf, ubuf, cnt)) | |
5227 | return -EFAULT; | |
5228 | ||
5229 | buf[cnt] = 0; | |
5230 | ||
5231 | clockstr = strstrip(buf); | |
5232 | ||
5233 | ret = tracing_set_clock(tr, clockstr); | |
5234 | if (ret) | |
5235 | return ret; | |
5236 | ||
5079f326 Z |
5237 | *fpos += cnt; |
5238 | ||
5239 | return cnt; | |
5240 | } | |
5241 | ||
13f16d20 LZ |
5242 | static int tracing_clock_open(struct inode *inode, struct file *file) |
5243 | { | |
7b85af63 SRRH |
5244 | struct trace_array *tr = inode->i_private; |
5245 | int ret; | |
5246 | ||
13f16d20 LZ |
5247 | if (tracing_disabled) |
5248 | return -ENODEV; | |
2b6080f2 | 5249 | |
7b85af63 SRRH |
5250 | if (trace_array_get(tr)) |
5251 | return -ENODEV; | |
5252 | ||
5253 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
5254 | if (ret < 0) | |
5255 | trace_array_put(tr); | |
5256 | ||
5257 | return ret; | |
13f16d20 LZ |
5258 | } |
5259 | ||
6de58e62 SRRH |
5260 | struct ftrace_buffer_info { |
5261 | struct trace_iterator iter; | |
5262 | void *spare; | |
5263 | unsigned int read; | |
5264 | }; | |
5265 | ||
debdd57f HT |
5266 | #ifdef CONFIG_TRACER_SNAPSHOT |
5267 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
5268 | { | |
6484c71c | 5269 | struct trace_array *tr = inode->i_private; |
debdd57f | 5270 | struct trace_iterator *iter; |
2b6080f2 | 5271 | struct seq_file *m; |
debdd57f HT |
5272 | int ret = 0; |
5273 | ||
ff451961 SRRH |
5274 | if (trace_array_get(tr) < 0) |
5275 | return -ENODEV; | |
5276 | ||
debdd57f | 5277 | if (file->f_mode & FMODE_READ) { |
6484c71c | 5278 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
5279 | if (IS_ERR(iter)) |
5280 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
5281 | } else { |
5282 | /* Writes still need the seq_file to hold the private data */ | |
f77d09a3 | 5283 | ret = -ENOMEM; |
2b6080f2 SR |
5284 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
5285 | if (!m) | |
f77d09a3 | 5286 | goto out; |
2b6080f2 SR |
5287 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
5288 | if (!iter) { | |
5289 | kfree(m); | |
f77d09a3 | 5290 | goto out; |
2b6080f2 | 5291 | } |
f77d09a3 AL |
5292 | ret = 0; |
5293 | ||
ff451961 | 5294 | iter->tr = tr; |
6484c71c ON |
5295 | iter->trace_buffer = &tr->max_buffer; |
5296 | iter->cpu_file = tracing_get_cpu(inode); | |
2b6080f2 SR |
5297 | m->private = iter; |
5298 | file->private_data = m; | |
debdd57f | 5299 | } |
f77d09a3 | 5300 | out: |
ff451961 SRRH |
5301 | if (ret < 0) |
5302 | trace_array_put(tr); | |
5303 | ||
debdd57f HT |
5304 | return ret; |
5305 | } | |
5306 | ||
5307 | static ssize_t | |
5308 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5309 | loff_t *ppos) | |
5310 | { | |
2b6080f2 SR |
5311 | struct seq_file *m = filp->private_data; |
5312 | struct trace_iterator *iter = m->private; | |
5313 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
5314 | unsigned long val; |
5315 | int ret; | |
5316 | ||
5317 | ret = tracing_update_buffers(); | |
5318 | if (ret < 0) | |
5319 | return ret; | |
5320 | ||
5321 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5322 | if (ret) | |
5323 | return ret; | |
5324 | ||
5325 | mutex_lock(&trace_types_lock); | |
5326 | ||
2b6080f2 | 5327 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
5328 | ret = -EBUSY; |
5329 | goto out; | |
5330 | } | |
5331 | ||
5332 | switch (val) { | |
5333 | case 0: | |
f1affcaa SRRH |
5334 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
5335 | ret = -EINVAL; | |
5336 | break; | |
debdd57f | 5337 | } |
3209cff4 SRRH |
5338 | if (tr->allocated_snapshot) |
5339 | free_snapshot(tr); | |
debdd57f HT |
5340 | break; |
5341 | case 1: | |
f1affcaa SRRH |
5342 | /* Only allow per-cpu swap if the ring buffer supports it */ |
5343 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
5344 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
5345 | ret = -EINVAL; | |
5346 | break; | |
5347 | } | |
5348 | #endif | |
45ad21ca | 5349 | if (!tr->allocated_snapshot) { |
3209cff4 | 5350 | ret = alloc_snapshot(tr); |
debdd57f HT |
5351 | if (ret < 0) |
5352 | break; | |
debdd57f | 5353 | } |
debdd57f HT |
5354 | local_irq_disable(); |
5355 | /* Now, we're going to swap */ | |
f1affcaa | 5356 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 5357 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 5358 | else |
ce9bae55 | 5359 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
5360 | local_irq_enable(); |
5361 | break; | |
5362 | default: | |
45ad21ca | 5363 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
5364 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
5365 | tracing_reset_online_cpus(&tr->max_buffer); | |
5366 | else | |
5367 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
5368 | } | |
debdd57f HT |
5369 | break; |
5370 | } | |
5371 | ||
5372 | if (ret >= 0) { | |
5373 | *ppos += cnt; | |
5374 | ret = cnt; | |
5375 | } | |
5376 | out: | |
5377 | mutex_unlock(&trace_types_lock); | |
5378 | return ret; | |
5379 | } | |
2b6080f2 SR |
5380 | |
5381 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
5382 | { | |
5383 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
5384 | int ret; |
5385 | ||
5386 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
5387 | |
5388 | if (file->f_mode & FMODE_READ) | |
ff451961 | 5389 | return ret; |
2b6080f2 SR |
5390 | |
5391 | /* If write only, the seq_file is just a stub */ | |
5392 | if (m) | |
5393 | kfree(m->private); | |
5394 | kfree(m); | |
5395 | ||
5396 | return 0; | |
5397 | } | |
5398 | ||
6de58e62 SRRH |
5399 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
5400 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5401 | size_t count, loff_t *ppos); | |
5402 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
5403 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5404 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
5405 | ||
5406 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
5407 | { | |
5408 | struct ftrace_buffer_info *info; | |
5409 | int ret; | |
5410 | ||
5411 | ret = tracing_buffers_open(inode, filp); | |
5412 | if (ret < 0) | |
5413 | return ret; | |
5414 | ||
5415 | info = filp->private_data; | |
5416 | ||
5417 | if (info->iter.trace->use_max_tr) { | |
5418 | tracing_buffers_release(inode, filp); | |
5419 | return -EBUSY; | |
5420 | } | |
5421 | ||
5422 | info->iter.snapshot = true; | |
5423 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
5424 | ||
5425 | return ret; | |
5426 | } | |
5427 | ||
debdd57f HT |
5428 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5429 | ||
5430 | ||
6508fa76 SF |
5431 | static const struct file_operations tracing_thresh_fops = { |
5432 | .open = tracing_open_generic, | |
5433 | .read = tracing_thresh_read, | |
5434 | .write = tracing_thresh_write, | |
5435 | .llseek = generic_file_llseek, | |
5436 | }; | |
5437 | ||
5e2336a0 | 5438 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
5439 | .open = tracing_open_generic, |
5440 | .read = tracing_max_lat_read, | |
5441 | .write = tracing_max_lat_write, | |
b444786f | 5442 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5443 | }; |
5444 | ||
5e2336a0 | 5445 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
5446 | .open = tracing_open_generic, |
5447 | .read = tracing_set_trace_read, | |
5448 | .write = tracing_set_trace_write, | |
b444786f | 5449 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5450 | }; |
5451 | ||
5e2336a0 | 5452 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 5453 | .open = tracing_open_pipe, |
2a2cc8f7 | 5454 | .poll = tracing_poll_pipe, |
4bf39a94 | 5455 | .read = tracing_read_pipe, |
3c56819b | 5456 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 5457 | .release = tracing_release_pipe, |
b444786f | 5458 | .llseek = no_llseek, |
b3806b43 SR |
5459 | }; |
5460 | ||
5e2336a0 | 5461 | static const struct file_operations tracing_entries_fops = { |
0bc392ee | 5462 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
5463 | .read = tracing_entries_read, |
5464 | .write = tracing_entries_write, | |
b444786f | 5465 | .llseek = generic_file_llseek, |
0bc392ee | 5466 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
5467 | }; |
5468 | ||
f81ab074 | 5469 | static const struct file_operations tracing_total_entries_fops = { |
7b85af63 | 5470 | .open = tracing_open_generic_tr, |
f81ab074 VN |
5471 | .read = tracing_total_entries_read, |
5472 | .llseek = generic_file_llseek, | |
7b85af63 | 5473 | .release = tracing_release_generic_tr, |
f81ab074 VN |
5474 | }; |
5475 | ||
4f271a2a | 5476 | static const struct file_operations tracing_free_buffer_fops = { |
7b85af63 | 5477 | .open = tracing_open_generic_tr, |
4f271a2a VN |
5478 | .write = tracing_free_buffer_write, |
5479 | .release = tracing_free_buffer_release, | |
5480 | }; | |
5481 | ||
5e2336a0 | 5482 | static const struct file_operations tracing_mark_fops = { |
7b85af63 | 5483 | .open = tracing_open_generic_tr, |
5bf9a1ee | 5484 | .write = tracing_mark_write, |
b444786f | 5485 | .llseek = generic_file_llseek, |
7b85af63 | 5486 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
5487 | }; |
5488 | ||
5079f326 | 5489 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
5490 | .open = tracing_clock_open, |
5491 | .read = seq_read, | |
5492 | .llseek = seq_lseek, | |
7b85af63 | 5493 | .release = tracing_single_release_tr, |
5079f326 Z |
5494 | .write = tracing_clock_write, |
5495 | }; | |
5496 | ||
debdd57f HT |
5497 | #ifdef CONFIG_TRACER_SNAPSHOT |
5498 | static const struct file_operations snapshot_fops = { | |
5499 | .open = tracing_snapshot_open, | |
5500 | .read = seq_read, | |
5501 | .write = tracing_snapshot_write, | |
098c879e | 5502 | .llseek = tracing_lseek, |
2b6080f2 | 5503 | .release = tracing_snapshot_release, |
debdd57f | 5504 | }; |
debdd57f | 5505 | |
6de58e62 SRRH |
5506 | static const struct file_operations snapshot_raw_fops = { |
5507 | .open = snapshot_raw_open, | |
5508 | .read = tracing_buffers_read, | |
5509 | .release = tracing_buffers_release, | |
5510 | .splice_read = tracing_buffers_splice_read, | |
5511 | .llseek = no_llseek, | |
2cadf913 SR |
5512 | }; |
5513 | ||
6de58e62 SRRH |
5514 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5515 | ||
2cadf913 SR |
5516 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
5517 | { | |
46ef2be0 | 5518 | struct trace_array *tr = inode->i_private; |
2cadf913 | 5519 | struct ftrace_buffer_info *info; |
7b85af63 | 5520 | int ret; |
2cadf913 SR |
5521 | |
5522 | if (tracing_disabled) | |
5523 | return -ENODEV; | |
5524 | ||
7b85af63 SRRH |
5525 | if (trace_array_get(tr) < 0) |
5526 | return -ENODEV; | |
5527 | ||
2cadf913 | 5528 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
7b85af63 SRRH |
5529 | if (!info) { |
5530 | trace_array_put(tr); | |
2cadf913 | 5531 | return -ENOMEM; |
7b85af63 | 5532 | } |
2cadf913 | 5533 | |
a695cb58 SRRH |
5534 | mutex_lock(&trace_types_lock); |
5535 | ||
cc60cdc9 | 5536 | info->iter.tr = tr; |
46ef2be0 | 5537 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 5538 | info->iter.trace = tr->current_trace; |
12883efb | 5539 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 5540 | info->spare = NULL; |
2cadf913 | 5541 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 5542 | info->read = (unsigned int)-1; |
2cadf913 SR |
5543 | |
5544 | filp->private_data = info; | |
5545 | ||
cf6ab6d9 SRRH |
5546 | tr->current_trace->ref++; |
5547 | ||
a695cb58 SRRH |
5548 | mutex_unlock(&trace_types_lock); |
5549 | ||
7b85af63 SRRH |
5550 | ret = nonseekable_open(inode, filp); |
5551 | if (ret < 0) | |
5552 | trace_array_put(tr); | |
5553 | ||
5554 | return ret; | |
2cadf913 SR |
5555 | } |
5556 | ||
cc60cdc9 SR |
5557 | static unsigned int |
5558 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
5559 | { | |
5560 | struct ftrace_buffer_info *info = filp->private_data; | |
5561 | struct trace_iterator *iter = &info->iter; | |
5562 | ||
5563 | return trace_poll(iter, filp, poll_table); | |
5564 | } | |
5565 | ||
2cadf913 SR |
5566 | static ssize_t |
5567 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5568 | size_t count, loff_t *ppos) | |
5569 | { | |
5570 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 5571 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5572 | ssize_t ret; |
6de58e62 | 5573 | ssize_t size; |
2cadf913 | 5574 | |
2dc5d12b SR |
5575 | if (!count) |
5576 | return 0; | |
5577 | ||
6de58e62 | 5578 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
5579 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
5580 | return -EBUSY; | |
6de58e62 SRRH |
5581 | #endif |
5582 | ||
ddd538f3 | 5583 | if (!info->spare) |
12883efb SRRH |
5584 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
5585 | iter->cpu_file); | |
ddd538f3 | 5586 | if (!info->spare) |
d716ff71 | 5587 | return -ENOMEM; |
ddd538f3 | 5588 | |
2cadf913 SR |
5589 | /* Do we have previous read data to read? */ |
5590 | if (info->read < PAGE_SIZE) | |
5591 | goto read; | |
5592 | ||
b627344f | 5593 | again: |
cc60cdc9 | 5594 | trace_access_lock(iter->cpu_file); |
12883efb | 5595 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
5596 | &info->spare, |
5597 | count, | |
cc60cdc9 SR |
5598 | iter->cpu_file, 0); |
5599 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 5600 | |
b627344f SR |
5601 | if (ret < 0) { |
5602 | if (trace_empty(iter)) { | |
d716ff71 SRRH |
5603 | if ((filp->f_flags & O_NONBLOCK)) |
5604 | return -EAGAIN; | |
5605 | ||
e30f53aa | 5606 | ret = wait_on_pipe(iter, false); |
d716ff71 SRRH |
5607 | if (ret) |
5608 | return ret; | |
5609 | ||
b627344f SR |
5610 | goto again; |
5611 | } | |
d716ff71 | 5612 | return 0; |
b627344f | 5613 | } |
436fc280 | 5614 | |
436fc280 | 5615 | info->read = 0; |
b627344f | 5616 | read: |
2cadf913 SR |
5617 | size = PAGE_SIZE - info->read; |
5618 | if (size > count) | |
5619 | size = count; | |
5620 | ||
5621 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
d716ff71 SRRH |
5622 | if (ret == size) |
5623 | return -EFAULT; | |
5624 | ||
2dc5d12b SR |
5625 | size -= ret; |
5626 | ||
2cadf913 SR |
5627 | *ppos += size; |
5628 | info->read += size; | |
5629 | ||
5630 | return size; | |
5631 | } | |
5632 | ||
5633 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
5634 | { | |
5635 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5636 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5637 | |
a695cb58 SRRH |
5638 | mutex_lock(&trace_types_lock); |
5639 | ||
cf6ab6d9 SRRH |
5640 | iter->tr->current_trace->ref--; |
5641 | ||
ff451961 | 5642 | __trace_array_put(iter->tr); |
2cadf913 | 5643 | |
ddd538f3 | 5644 | if (info->spare) |
12883efb | 5645 | ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); |
2cadf913 SR |
5646 | kfree(info); |
5647 | ||
a695cb58 SRRH |
5648 | mutex_unlock(&trace_types_lock); |
5649 | ||
2cadf913 SR |
5650 | return 0; |
5651 | } | |
5652 | ||
5653 | struct buffer_ref { | |
5654 | struct ring_buffer *buffer; | |
5655 | void *page; | |
5656 | int ref; | |
5657 | }; | |
5658 | ||
5659 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
5660 | struct pipe_buffer *buf) | |
5661 | { | |
5662 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5663 | ||
5664 | if (--ref->ref) | |
5665 | return; | |
5666 | ||
5667 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5668 | kfree(ref); | |
5669 | buf->private = 0; | |
5670 | } | |
5671 | ||
2cadf913 SR |
5672 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
5673 | struct pipe_buffer *buf) | |
5674 | { | |
5675 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5676 | ||
5677 | ref->ref++; | |
5678 | } | |
5679 | ||
5680 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 5681 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 | 5682 | .can_merge = 0, |
2cadf913 SR |
5683 | .confirm = generic_pipe_buf_confirm, |
5684 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 5685 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
5686 | .get = buffer_pipe_buf_get, |
5687 | }; | |
5688 | ||
5689 | /* | |
5690 | * Callback from splice_to_pipe(), if we need to release some pages | |
5691 | * at the end of the spd in case we error'ed out in filling the pipe. | |
5692 | */ | |
5693 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
5694 | { | |
5695 | struct buffer_ref *ref = | |
5696 | (struct buffer_ref *)spd->partial[i].private; | |
5697 | ||
5698 | if (--ref->ref) | |
5699 | return; | |
5700 | ||
5701 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5702 | kfree(ref); | |
5703 | spd->partial[i].private = 0; | |
5704 | } | |
5705 | ||
5706 | static ssize_t | |
5707 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5708 | struct pipe_inode_info *pipe, size_t len, | |
5709 | unsigned int flags) | |
5710 | { | |
5711 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5712 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
5713 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
5714 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 5715 | struct splice_pipe_desc spd = { |
35f3d14d JA |
5716 | .pages = pages_def, |
5717 | .partial = partial_def, | |
047fe360 | 5718 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
5719 | .flags = flags, |
5720 | .ops = &buffer_pipe_buf_ops, | |
5721 | .spd_release = buffer_spd_release, | |
5722 | }; | |
5723 | struct buffer_ref *ref; | |
93459c6c | 5724 | int entries, size, i; |
07906da7 | 5725 | ssize_t ret = 0; |
2cadf913 | 5726 | |
6de58e62 | 5727 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
5728 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
5729 | return -EBUSY; | |
6de58e62 SRRH |
5730 | #endif |
5731 | ||
d716ff71 SRRH |
5732 | if (splice_grow_spd(pipe, &spd)) |
5733 | return -ENOMEM; | |
35f3d14d | 5734 | |
d716ff71 SRRH |
5735 | if (*ppos & (PAGE_SIZE - 1)) |
5736 | return -EINVAL; | |
93cfb3c9 LJ |
5737 | |
5738 | if (len & (PAGE_SIZE - 1)) { | |
d716ff71 SRRH |
5739 | if (len < PAGE_SIZE) |
5740 | return -EINVAL; | |
93cfb3c9 LJ |
5741 | len &= PAGE_MASK; |
5742 | } | |
5743 | ||
cc60cdc9 SR |
5744 | again: |
5745 | trace_access_lock(iter->cpu_file); | |
12883efb | 5746 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 5747 | |
a786c06d | 5748 | for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
5749 | struct page *page; |
5750 | int r; | |
5751 | ||
5752 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
07906da7 RV |
5753 | if (!ref) { |
5754 | ret = -ENOMEM; | |
2cadf913 | 5755 | break; |
07906da7 | 5756 | } |
2cadf913 | 5757 | |
7267fa68 | 5758 | ref->ref = 1; |
12883efb | 5759 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 5760 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
2cadf913 | 5761 | if (!ref->page) { |
07906da7 | 5762 | ret = -ENOMEM; |
2cadf913 SR |
5763 | kfree(ref); |
5764 | break; | |
5765 | } | |
5766 | ||
5767 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 5768 | len, iter->cpu_file, 1); |
2cadf913 | 5769 | if (r < 0) { |
7ea59064 | 5770 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
5771 | kfree(ref); |
5772 | break; | |
5773 | } | |
5774 | ||
5775 | /* | |
5776 | * zero out any left over data, this is going to | |
5777 | * user land. | |
5778 | */ | |
5779 | size = ring_buffer_page_len(ref->page); | |
5780 | if (size < PAGE_SIZE) | |
5781 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
5782 | ||
5783 | page = virt_to_page(ref->page); | |
5784 | ||
5785 | spd.pages[i] = page; | |
5786 | spd.partial[i].len = PAGE_SIZE; | |
5787 | spd.partial[i].offset = 0; | |
5788 | spd.partial[i].private = (unsigned long)ref; | |
5789 | spd.nr_pages++; | |
93cfb3c9 | 5790 | *ppos += PAGE_SIZE; |
93459c6c | 5791 | |
12883efb | 5792 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
5793 | } |
5794 | ||
cc60cdc9 | 5795 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
5796 | spd.nr_pages = i; |
5797 | ||
5798 | /* did we read anything? */ | |
5799 | if (!spd.nr_pages) { | |
07906da7 | 5800 | if (ret) |
d716ff71 SRRH |
5801 | return ret; |
5802 | ||
5803 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) | |
5804 | return -EAGAIN; | |
07906da7 | 5805 | |
e30f53aa | 5806 | ret = wait_on_pipe(iter, true); |
8b8b3683 | 5807 | if (ret) |
d716ff71 | 5808 | return ret; |
e30f53aa | 5809 | |
cc60cdc9 | 5810 | goto again; |
2cadf913 SR |
5811 | } |
5812 | ||
5813 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 5814 | splice_shrink_spd(&spd); |
6de58e62 | 5815 | |
2cadf913 SR |
5816 | return ret; |
5817 | } | |
5818 | ||
5819 | static const struct file_operations tracing_buffers_fops = { | |
5820 | .open = tracing_buffers_open, | |
5821 | .read = tracing_buffers_read, | |
cc60cdc9 | 5822 | .poll = tracing_buffers_poll, |
2cadf913 SR |
5823 | .release = tracing_buffers_release, |
5824 | .splice_read = tracing_buffers_splice_read, | |
5825 | .llseek = no_llseek, | |
5826 | }; | |
5827 | ||
c8d77183 SR |
5828 | static ssize_t |
5829 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
5830 | size_t count, loff_t *ppos) | |
5831 | { | |
4d3435b8 ON |
5832 | struct inode *inode = file_inode(filp); |
5833 | struct trace_array *tr = inode->i_private; | |
12883efb | 5834 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
4d3435b8 | 5835 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
5836 | struct trace_seq *s; |
5837 | unsigned long cnt; | |
c64e148a VN |
5838 | unsigned long long t; |
5839 | unsigned long usec_rem; | |
c8d77183 | 5840 | |
e4f2d10f | 5841 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 5842 | if (!s) |
a646365c | 5843 | return -ENOMEM; |
c8d77183 SR |
5844 | |
5845 | trace_seq_init(s); | |
5846 | ||
12883efb | 5847 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5848 | trace_seq_printf(s, "entries: %ld\n", cnt); |
5849 | ||
12883efb | 5850 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5851 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
5852 | ||
12883efb | 5853 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5854 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
5855 | ||
12883efb | 5856 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
5857 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
5858 | ||
58e8eedf | 5859 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 5860 | /* local or global for trace_clock */ |
12883efb | 5861 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
5862 | usec_rem = do_div(t, USEC_PER_SEC); |
5863 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
5864 | t, usec_rem); | |
5865 | ||
12883efb | 5866 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
5867 | usec_rem = do_div(t, USEC_PER_SEC); |
5868 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
5869 | } else { | |
5870 | /* counter or tsc mode for trace_clock */ | |
5871 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 5872 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 5873 | |
11043d8b | 5874 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 5875 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 5876 | } |
c64e148a | 5877 | |
12883efb | 5878 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
5879 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
5880 | ||
12883efb | 5881 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
5882 | trace_seq_printf(s, "read events: %ld\n", cnt); |
5883 | ||
5ac48378 SRRH |
5884 | count = simple_read_from_buffer(ubuf, count, ppos, |
5885 | s->buffer, trace_seq_used(s)); | |
c8d77183 SR |
5886 | |
5887 | kfree(s); | |
5888 | ||
5889 | return count; | |
5890 | } | |
5891 | ||
5892 | static const struct file_operations tracing_stats_fops = { | |
4d3435b8 | 5893 | .open = tracing_open_generic_tr, |
c8d77183 | 5894 | .read = tracing_stats_read, |
b444786f | 5895 | .llseek = generic_file_llseek, |
4d3435b8 | 5896 | .release = tracing_release_generic_tr, |
c8d77183 SR |
5897 | }; |
5898 | ||
bc0c38d1 SR |
5899 | #ifdef CONFIG_DYNAMIC_FTRACE |
5900 | ||
b807c3d0 SR |
5901 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
5902 | { | |
5903 | return 0; | |
5904 | } | |
5905 | ||
bc0c38d1 | 5906 | static ssize_t |
b807c3d0 | 5907 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
5908 | size_t cnt, loff_t *ppos) |
5909 | { | |
a26a2a27 SR |
5910 | static char ftrace_dyn_info_buffer[1024]; |
5911 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 5912 | unsigned long *p = filp->private_data; |
b807c3d0 | 5913 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 5914 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
5915 | int r; |
5916 | ||
b807c3d0 SR |
5917 | mutex_lock(&dyn_info_mutex); |
5918 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 5919 | |
a26a2a27 | 5920 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
5921 | buf[r++] = '\n'; |
5922 | ||
5923 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5924 | ||
5925 | mutex_unlock(&dyn_info_mutex); | |
5926 | ||
5927 | return r; | |
bc0c38d1 SR |
5928 | } |
5929 | ||
5e2336a0 | 5930 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 5931 | .open = tracing_open_generic, |
b807c3d0 | 5932 | .read = tracing_read_dyn_info, |
b444786f | 5933 | .llseek = generic_file_llseek, |
bc0c38d1 | 5934 | }; |
77fd5c15 | 5935 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 5936 | |
77fd5c15 SRRH |
5937 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
5938 | static void | |
5939 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
5940 | { | |
5941 | tracing_snapshot(); | |
5942 | } | |
bc0c38d1 | 5943 | |
77fd5c15 SRRH |
5944 | static void |
5945 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
bc0c38d1 | 5946 | { |
77fd5c15 SRRH |
5947 | unsigned long *count = (long *)data; |
5948 | ||
5949 | if (!*count) | |
5950 | return; | |
bc0c38d1 | 5951 | |
77fd5c15 SRRH |
5952 | if (*count != -1) |
5953 | (*count)--; | |
5954 | ||
5955 | tracing_snapshot(); | |
5956 | } | |
5957 | ||
5958 | static int | |
5959 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
5960 | struct ftrace_probe_ops *ops, void *data) | |
5961 | { | |
5962 | long count = (long)data; | |
5963 | ||
5964 | seq_printf(m, "%ps:", (void *)ip); | |
5965 | ||
fa6f0cc7 | 5966 | seq_puts(m, "snapshot"); |
77fd5c15 SRRH |
5967 | |
5968 | if (count == -1) | |
fa6f0cc7 | 5969 | seq_puts(m, ":unlimited\n"); |
77fd5c15 SRRH |
5970 | else |
5971 | seq_printf(m, ":count=%ld\n", count); | |
5972 | ||
5973 | return 0; | |
5974 | } | |
5975 | ||
5976 | static struct ftrace_probe_ops snapshot_probe_ops = { | |
5977 | .func = ftrace_snapshot, | |
5978 | .print = ftrace_snapshot_print, | |
5979 | }; | |
5980 | ||
5981 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
5982 | .func = ftrace_count_snapshot, | |
5983 | .print = ftrace_snapshot_print, | |
5984 | }; | |
5985 | ||
5986 | static int | |
5987 | ftrace_trace_snapshot_callback(struct ftrace_hash *hash, | |
5988 | char *glob, char *cmd, char *param, int enable) | |
5989 | { | |
5990 | struct ftrace_probe_ops *ops; | |
5991 | void *count = (void *)-1; | |
5992 | char *number; | |
5993 | int ret; | |
5994 | ||
5995 | /* hash funcs only work with set_ftrace_filter */ | |
5996 | if (!enable) | |
5997 | return -EINVAL; | |
5998 | ||
5999 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
6000 | ||
6001 | if (glob[0] == '!') { | |
6002 | unregister_ftrace_function_probe_func(glob+1, ops); | |
6003 | return 0; | |
6004 | } | |
6005 | ||
6006 | if (!param) | |
6007 | goto out_reg; | |
6008 | ||
6009 | number = strsep(¶m, ":"); | |
6010 | ||
6011 | if (!strlen(number)) | |
6012 | goto out_reg; | |
6013 | ||
6014 | /* | |
6015 | * We use the callback data field (which is a pointer) | |
6016 | * as our counter. | |
6017 | */ | |
6018 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
6019 | if (ret) | |
6020 | return ret; | |
6021 | ||
6022 | out_reg: | |
6023 | ret = register_ftrace_function_probe(glob, ops, count); | |
6024 | ||
6025 | if (ret >= 0) | |
6026 | alloc_snapshot(&global_trace); | |
6027 | ||
6028 | return ret < 0 ? ret : 0; | |
6029 | } | |
6030 | ||
6031 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
6032 | .name = "snapshot", | |
6033 | .func = ftrace_trace_snapshot_callback, | |
6034 | }; | |
6035 | ||
38de93ab | 6036 | static __init int register_snapshot_cmd(void) |
77fd5c15 SRRH |
6037 | { |
6038 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
6039 | } | |
6040 | #else | |
38de93ab | 6041 | static inline __init int register_snapshot_cmd(void) { return 0; } |
77fd5c15 | 6042 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ |
bc0c38d1 | 6043 | |
7eeafbca | 6044 | static struct dentry *tracing_get_dentry(struct trace_array *tr) |
bc0c38d1 | 6045 | { |
8434dc93 SRRH |
6046 | if (WARN_ON(!tr->dir)) |
6047 | return ERR_PTR(-ENODEV); | |
6048 | ||
6049 | /* Top directory uses NULL as the parent */ | |
6050 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
6051 | return NULL; | |
6052 | ||
6053 | /* All sub buffers have a descriptor */ | |
2b6080f2 | 6054 | return tr->dir; |
bc0c38d1 SR |
6055 | } |
6056 | ||
2b6080f2 | 6057 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 6058 | { |
b04cc6b1 FW |
6059 | struct dentry *d_tracer; |
6060 | ||
2b6080f2 SR |
6061 | if (tr->percpu_dir) |
6062 | return tr->percpu_dir; | |
b04cc6b1 | 6063 | |
7eeafbca | 6064 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 6065 | if (IS_ERR(d_tracer)) |
b04cc6b1 FW |
6066 | return NULL; |
6067 | ||
8434dc93 | 6068 | tr->percpu_dir = tracefs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 6069 | |
2b6080f2 | 6070 | WARN_ONCE(!tr->percpu_dir, |
8434dc93 | 6071 | "Could not create tracefs directory 'per_cpu/%d'\n", cpu); |
b04cc6b1 | 6072 | |
2b6080f2 | 6073 | return tr->percpu_dir; |
b04cc6b1 FW |
6074 | } |
6075 | ||
649e9c70 ON |
6076 | static struct dentry * |
6077 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
6078 | void *data, long cpu, const struct file_operations *fops) | |
6079 | { | |
6080 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
6081 | ||
6082 | if (ret) /* See tracing_get_cpu() */ | |
7682c918 | 6083 | d_inode(ret)->i_cdev = (void *)(cpu + 1); |
649e9c70 ON |
6084 | return ret; |
6085 | } | |
6086 | ||
2b6080f2 | 6087 | static void |
8434dc93 | 6088 | tracing_init_tracefs_percpu(struct trace_array *tr, long cpu) |
b04cc6b1 | 6089 | { |
2b6080f2 | 6090 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 6091 | struct dentry *d_cpu; |
dd49a38c | 6092 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 6093 | |
0a3d7ce7 NK |
6094 | if (!d_percpu) |
6095 | return; | |
6096 | ||
dd49a38c | 6097 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8434dc93 | 6098 | d_cpu = tracefs_create_dir(cpu_dir, d_percpu); |
8656e7a2 | 6099 | if (!d_cpu) { |
8434dc93 | 6100 | pr_warning("Could not create tracefs '%s' entry\n", cpu_dir); |
8656e7a2 FW |
6101 | return; |
6102 | } | |
b04cc6b1 | 6103 | |
8656e7a2 | 6104 | /* per cpu trace_pipe */ |
649e9c70 | 6105 | trace_create_cpu_file("trace_pipe", 0444, d_cpu, |
15544209 | 6106 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
6107 | |
6108 | /* per cpu trace */ | |
649e9c70 | 6109 | trace_create_cpu_file("trace", 0644, d_cpu, |
6484c71c | 6110 | tr, cpu, &tracing_fops); |
7f96f93f | 6111 | |
649e9c70 | 6112 | trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, |
46ef2be0 | 6113 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 6114 | |
649e9c70 | 6115 | trace_create_cpu_file("stats", 0444, d_cpu, |
4d3435b8 | 6116 | tr, cpu, &tracing_stats_fops); |
438ced17 | 6117 | |
649e9c70 | 6118 | trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, |
0bc392ee | 6119 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
6120 | |
6121 | #ifdef CONFIG_TRACER_SNAPSHOT | |
649e9c70 | 6122 | trace_create_cpu_file("snapshot", 0644, d_cpu, |
6484c71c | 6123 | tr, cpu, &snapshot_fops); |
6de58e62 | 6124 | |
649e9c70 | 6125 | trace_create_cpu_file("snapshot_raw", 0444, d_cpu, |
46ef2be0 | 6126 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 6127 | #endif |
b04cc6b1 FW |
6128 | } |
6129 | ||
60a11774 SR |
6130 | #ifdef CONFIG_FTRACE_SELFTEST |
6131 | /* Let selftest have access to static functions in this file */ | |
6132 | #include "trace_selftest.c" | |
6133 | #endif | |
6134 | ||
577b785f SR |
6135 | struct trace_option_dentry { |
6136 | struct tracer_opt *opt; | |
6137 | struct tracer_flags *flags; | |
2b6080f2 | 6138 | struct trace_array *tr; |
577b785f SR |
6139 | struct dentry *entry; |
6140 | }; | |
6141 | ||
6142 | static ssize_t | |
6143 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
6144 | loff_t *ppos) | |
6145 | { | |
6146 | struct trace_option_dentry *topt = filp->private_data; | |
6147 | char *buf; | |
6148 | ||
6149 | if (topt->flags->val & topt->opt->bit) | |
6150 | buf = "1\n"; | |
6151 | else | |
6152 | buf = "0\n"; | |
6153 | ||
6154 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
6155 | } | |
6156 | ||
6157 | static ssize_t | |
6158 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
6159 | loff_t *ppos) | |
6160 | { | |
6161 | struct trace_option_dentry *topt = filp->private_data; | |
6162 | unsigned long val; | |
577b785f SR |
6163 | int ret; |
6164 | ||
22fe9b54 PH |
6165 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
6166 | if (ret) | |
577b785f SR |
6167 | return ret; |
6168 | ||
8d18eaaf LZ |
6169 | if (val != 0 && val != 1) |
6170 | return -EINVAL; | |
577b785f | 6171 | |
8d18eaaf | 6172 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 6173 | mutex_lock(&trace_types_lock); |
8c1a49ae | 6174 | ret = __set_tracer_option(topt->tr, topt->flags, |
c757bea9 | 6175 | topt->opt, !val); |
577b785f SR |
6176 | mutex_unlock(&trace_types_lock); |
6177 | if (ret) | |
6178 | return ret; | |
577b785f SR |
6179 | } |
6180 | ||
6181 | *ppos += cnt; | |
6182 | ||
6183 | return cnt; | |
6184 | } | |
6185 | ||
6186 | ||
6187 | static const struct file_operations trace_options_fops = { | |
6188 | .open = tracing_open_generic, | |
6189 | .read = trace_options_read, | |
6190 | .write = trace_options_write, | |
b444786f | 6191 | .llseek = generic_file_llseek, |
577b785f SR |
6192 | }; |
6193 | ||
a8259075 SR |
6194 | static ssize_t |
6195 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
6196 | loff_t *ppos) | |
6197 | { | |
6198 | long index = (long)filp->private_data; | |
6199 | char *buf; | |
6200 | ||
6201 | if (trace_flags & (1 << index)) | |
6202 | buf = "1\n"; | |
6203 | else | |
6204 | buf = "0\n"; | |
6205 | ||
6206 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
6207 | } | |
6208 | ||
6209 | static ssize_t | |
6210 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
6211 | loff_t *ppos) | |
6212 | { | |
2b6080f2 | 6213 | struct trace_array *tr = &global_trace; |
a8259075 | 6214 | long index = (long)filp->private_data; |
a8259075 SR |
6215 | unsigned long val; |
6216 | int ret; | |
6217 | ||
22fe9b54 PH |
6218 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
6219 | if (ret) | |
a8259075 SR |
6220 | return ret; |
6221 | ||
f2d84b65 | 6222 | if (val != 0 && val != 1) |
a8259075 | 6223 | return -EINVAL; |
69d34da2 SRRH |
6224 | |
6225 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 6226 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 6227 | mutex_unlock(&trace_types_lock); |
a8259075 | 6228 | |
613f04a0 SRRH |
6229 | if (ret < 0) |
6230 | return ret; | |
6231 | ||
a8259075 SR |
6232 | *ppos += cnt; |
6233 | ||
6234 | return cnt; | |
6235 | } | |
6236 | ||
a8259075 SR |
6237 | static const struct file_operations trace_options_core_fops = { |
6238 | .open = tracing_open_generic, | |
6239 | .read = trace_options_core_read, | |
6240 | .write = trace_options_core_write, | |
b444786f | 6241 | .llseek = generic_file_llseek, |
a8259075 SR |
6242 | }; |
6243 | ||
5452af66 | 6244 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 6245 | umode_t mode, |
5452af66 FW |
6246 | struct dentry *parent, |
6247 | void *data, | |
6248 | const struct file_operations *fops) | |
6249 | { | |
6250 | struct dentry *ret; | |
6251 | ||
8434dc93 | 6252 | ret = tracefs_create_file(name, mode, parent, data, fops); |
5452af66 | 6253 | if (!ret) |
8434dc93 | 6254 | pr_warning("Could not create tracefs '%s' entry\n", name); |
5452af66 FW |
6255 | |
6256 | return ret; | |
6257 | } | |
6258 | ||
6259 | ||
2b6080f2 | 6260 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
6261 | { |
6262 | struct dentry *d_tracer; | |
a8259075 | 6263 | |
2b6080f2 SR |
6264 | if (tr->options) |
6265 | return tr->options; | |
a8259075 | 6266 | |
7eeafbca | 6267 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 6268 | if (IS_ERR(d_tracer)) |
a8259075 SR |
6269 | return NULL; |
6270 | ||
8434dc93 | 6271 | tr->options = tracefs_create_dir("options", d_tracer); |
2b6080f2 | 6272 | if (!tr->options) { |
8434dc93 | 6273 | pr_warning("Could not create tracefs directory 'options'\n"); |
a8259075 SR |
6274 | return NULL; |
6275 | } | |
6276 | ||
2b6080f2 | 6277 | return tr->options; |
a8259075 SR |
6278 | } |
6279 | ||
577b785f | 6280 | static void |
2b6080f2 SR |
6281 | create_trace_option_file(struct trace_array *tr, |
6282 | struct trace_option_dentry *topt, | |
577b785f SR |
6283 | struct tracer_flags *flags, |
6284 | struct tracer_opt *opt) | |
6285 | { | |
6286 | struct dentry *t_options; | |
577b785f | 6287 | |
2b6080f2 | 6288 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
6289 | if (!t_options) |
6290 | return; | |
6291 | ||
6292 | topt->flags = flags; | |
6293 | topt->opt = opt; | |
2b6080f2 | 6294 | topt->tr = tr; |
577b785f | 6295 | |
5452af66 | 6296 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
6297 | &trace_options_fops); |
6298 | ||
577b785f SR |
6299 | } |
6300 | ||
6301 | static struct trace_option_dentry * | |
2b6080f2 | 6302 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
6303 | { |
6304 | struct trace_option_dentry *topts; | |
6305 | struct tracer_flags *flags; | |
6306 | struct tracer_opt *opts; | |
6307 | int cnt; | |
6308 | ||
6309 | if (!tracer) | |
6310 | return NULL; | |
6311 | ||
6312 | flags = tracer->flags; | |
6313 | ||
6314 | if (!flags || !flags->opts) | |
6315 | return NULL; | |
6316 | ||
6317 | opts = flags->opts; | |
6318 | ||
6319 | for (cnt = 0; opts[cnt].name; cnt++) | |
6320 | ; | |
6321 | ||
0cfe8245 | 6322 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
6323 | if (!topts) |
6324 | return NULL; | |
6325 | ||
6326 | for (cnt = 0; opts[cnt].name; cnt++) | |
2b6080f2 | 6327 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f SR |
6328 | &opts[cnt]); |
6329 | ||
6330 | return topts; | |
6331 | } | |
6332 | ||
6333 | static void | |
6334 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
6335 | { | |
6336 | int cnt; | |
6337 | ||
6338 | if (!topts) | |
6339 | return; | |
6340 | ||
3f4d8f78 | 6341 | for (cnt = 0; topts[cnt].opt; cnt++) |
8434dc93 | 6342 | tracefs_remove(topts[cnt].entry); |
577b785f SR |
6343 | |
6344 | kfree(topts); | |
6345 | } | |
6346 | ||
a8259075 | 6347 | static struct dentry * |
2b6080f2 SR |
6348 | create_trace_option_core_file(struct trace_array *tr, |
6349 | const char *option, long index) | |
a8259075 SR |
6350 | { |
6351 | struct dentry *t_options; | |
a8259075 | 6352 | |
2b6080f2 | 6353 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
6354 | if (!t_options) |
6355 | return NULL; | |
6356 | ||
5452af66 | 6357 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 6358 | &trace_options_core_fops); |
a8259075 SR |
6359 | } |
6360 | ||
2b6080f2 | 6361 | static __init void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
6362 | { |
6363 | struct dentry *t_options; | |
a8259075 SR |
6364 | int i; |
6365 | ||
2b6080f2 | 6366 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
6367 | if (!t_options) |
6368 | return; | |
6369 | ||
5452af66 | 6370 | for (i = 0; trace_options[i]; i++) |
2b6080f2 | 6371 | create_trace_option_core_file(tr, trace_options[i], i); |
a8259075 SR |
6372 | } |
6373 | ||
499e5470 SR |
6374 | static ssize_t |
6375 | rb_simple_read(struct file *filp, char __user *ubuf, | |
6376 | size_t cnt, loff_t *ppos) | |
6377 | { | |
348f0fc2 | 6378 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
6379 | char buf[64]; |
6380 | int r; | |
6381 | ||
10246fa3 | 6382 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
6383 | r = sprintf(buf, "%d\n", r); |
6384 | ||
6385 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
6386 | } | |
6387 | ||
6388 | static ssize_t | |
6389 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
6390 | size_t cnt, loff_t *ppos) | |
6391 | { | |
348f0fc2 | 6392 | struct trace_array *tr = filp->private_data; |
12883efb | 6393 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
6394 | unsigned long val; |
6395 | int ret; | |
6396 | ||
6397 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
6398 | if (ret) | |
6399 | return ret; | |
6400 | ||
6401 | if (buffer) { | |
2df8f8a6 SR |
6402 | mutex_lock(&trace_types_lock); |
6403 | if (val) { | |
10246fa3 | 6404 | tracer_tracing_on(tr); |
2b6080f2 SR |
6405 | if (tr->current_trace->start) |
6406 | tr->current_trace->start(tr); | |
2df8f8a6 | 6407 | } else { |
10246fa3 | 6408 | tracer_tracing_off(tr); |
2b6080f2 SR |
6409 | if (tr->current_trace->stop) |
6410 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
6411 | } |
6412 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
6413 | } |
6414 | ||
6415 | (*ppos)++; | |
6416 | ||
6417 | return cnt; | |
6418 | } | |
6419 | ||
6420 | static const struct file_operations rb_simple_fops = { | |
7b85af63 | 6421 | .open = tracing_open_generic_tr, |
499e5470 SR |
6422 | .read = rb_simple_read, |
6423 | .write = rb_simple_write, | |
7b85af63 | 6424 | .release = tracing_release_generic_tr, |
499e5470 SR |
6425 | .llseek = default_llseek, |
6426 | }; | |
6427 | ||
277ba044 SR |
6428 | struct dentry *trace_instance_dir; |
6429 | ||
6430 | static void | |
8434dc93 | 6431 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer); |
277ba044 | 6432 | |
55034cd6 SRRH |
6433 | static int |
6434 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
6435 | { |
6436 | enum ring_buffer_flags rb_flags; | |
737223fb SRRH |
6437 | |
6438 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; | |
6439 | ||
dced341b SRRH |
6440 | buf->tr = tr; |
6441 | ||
55034cd6 SRRH |
6442 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
6443 | if (!buf->buffer) | |
6444 | return -ENOMEM; | |
737223fb | 6445 | |
55034cd6 SRRH |
6446 | buf->data = alloc_percpu(struct trace_array_cpu); |
6447 | if (!buf->data) { | |
6448 | ring_buffer_free(buf->buffer); | |
6449 | return -ENOMEM; | |
6450 | } | |
737223fb | 6451 | |
737223fb SRRH |
6452 | /* Allocate the first page for all buffers */ |
6453 | set_buffer_entries(&tr->trace_buffer, | |
6454 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
6455 | ||
55034cd6 SRRH |
6456 | return 0; |
6457 | } | |
737223fb | 6458 | |
55034cd6 SRRH |
6459 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
6460 | { | |
6461 | int ret; | |
737223fb | 6462 | |
55034cd6 SRRH |
6463 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
6464 | if (ret) | |
6465 | return ret; | |
737223fb | 6466 | |
55034cd6 SRRH |
6467 | #ifdef CONFIG_TRACER_MAX_TRACE |
6468 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
6469 | allocate_snapshot ? size : 1); | |
6470 | if (WARN_ON(ret)) { | |
737223fb | 6471 | ring_buffer_free(tr->trace_buffer.buffer); |
55034cd6 SRRH |
6472 | free_percpu(tr->trace_buffer.data); |
6473 | return -ENOMEM; | |
6474 | } | |
6475 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 6476 | |
55034cd6 SRRH |
6477 | /* |
6478 | * Only the top level trace array gets its snapshot allocated | |
6479 | * from the kernel command line. | |
6480 | */ | |
6481 | allocate_snapshot = false; | |
737223fb | 6482 | #endif |
55034cd6 | 6483 | return 0; |
737223fb SRRH |
6484 | } |
6485 | ||
f0b70cc4 SRRH |
6486 | static void free_trace_buffer(struct trace_buffer *buf) |
6487 | { | |
6488 | if (buf->buffer) { | |
6489 | ring_buffer_free(buf->buffer); | |
6490 | buf->buffer = NULL; | |
6491 | free_percpu(buf->data); | |
6492 | buf->data = NULL; | |
6493 | } | |
6494 | } | |
6495 | ||
23aaa3c1 SRRH |
6496 | static void free_trace_buffers(struct trace_array *tr) |
6497 | { | |
6498 | if (!tr) | |
6499 | return; | |
6500 | ||
f0b70cc4 | 6501 | free_trace_buffer(&tr->trace_buffer); |
23aaa3c1 SRRH |
6502 | |
6503 | #ifdef CONFIG_TRACER_MAX_TRACE | |
f0b70cc4 | 6504 | free_trace_buffer(&tr->max_buffer); |
23aaa3c1 SRRH |
6505 | #endif |
6506 | } | |
6507 | ||
eae47358 | 6508 | static int instance_mkdir(const char *name) |
737223fb | 6509 | { |
277ba044 SR |
6510 | struct trace_array *tr; |
6511 | int ret; | |
277ba044 SR |
6512 | |
6513 | mutex_lock(&trace_types_lock); | |
6514 | ||
6515 | ret = -EEXIST; | |
6516 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6517 | if (tr->name && strcmp(tr->name, name) == 0) | |
6518 | goto out_unlock; | |
6519 | } | |
6520 | ||
6521 | ret = -ENOMEM; | |
6522 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
6523 | if (!tr) | |
6524 | goto out_unlock; | |
6525 | ||
6526 | tr->name = kstrdup(name, GFP_KERNEL); | |
6527 | if (!tr->name) | |
6528 | goto out_free_tr; | |
6529 | ||
ccfe9e42 AL |
6530 | if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) |
6531 | goto out_free_tr; | |
6532 | ||
6533 | cpumask_copy(tr->tracing_cpumask, cpu_all_mask); | |
6534 | ||
277ba044 SR |
6535 | raw_spin_lock_init(&tr->start_lock); |
6536 | ||
0b9b12c1 SRRH |
6537 | tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
6538 | ||
277ba044 SR |
6539 | tr->current_trace = &nop_trace; |
6540 | ||
6541 | INIT_LIST_HEAD(&tr->systems); | |
6542 | INIT_LIST_HEAD(&tr->events); | |
6543 | ||
737223fb | 6544 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
6545 | goto out_free_tr; |
6546 | ||
8434dc93 | 6547 | tr->dir = tracefs_create_dir(name, trace_instance_dir); |
277ba044 SR |
6548 | if (!tr->dir) |
6549 | goto out_free_tr; | |
6550 | ||
6551 | ret = event_trace_add_tracer(tr->dir, tr); | |
609e85a7 | 6552 | if (ret) { |
8434dc93 | 6553 | tracefs_remove_recursive(tr->dir); |
277ba044 | 6554 | goto out_free_tr; |
609e85a7 | 6555 | } |
277ba044 | 6556 | |
8434dc93 | 6557 | init_tracer_tracefs(tr, tr->dir); |
277ba044 SR |
6558 | |
6559 | list_add(&tr->list, &ftrace_trace_arrays); | |
6560 | ||
6561 | mutex_unlock(&trace_types_lock); | |
6562 | ||
6563 | return 0; | |
6564 | ||
6565 | out_free_tr: | |
23aaa3c1 | 6566 | free_trace_buffers(tr); |
ccfe9e42 | 6567 | free_cpumask_var(tr->tracing_cpumask); |
277ba044 SR |
6568 | kfree(tr->name); |
6569 | kfree(tr); | |
6570 | ||
6571 | out_unlock: | |
6572 | mutex_unlock(&trace_types_lock); | |
6573 | ||
6574 | return ret; | |
6575 | ||
6576 | } | |
6577 | ||
eae47358 | 6578 | static int instance_rmdir(const char *name) |
0c8916c3 SR |
6579 | { |
6580 | struct trace_array *tr; | |
6581 | int found = 0; | |
6582 | int ret; | |
6583 | ||
6584 | mutex_lock(&trace_types_lock); | |
6585 | ||
6586 | ret = -ENODEV; | |
6587 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6588 | if (tr->name && strcmp(tr->name, name) == 0) { | |
6589 | found = 1; | |
6590 | break; | |
6591 | } | |
6592 | } | |
6593 | if (!found) | |
6594 | goto out_unlock; | |
6595 | ||
a695cb58 | 6596 | ret = -EBUSY; |
cf6ab6d9 | 6597 | if (tr->ref || (tr->current_trace && tr->current_trace->ref)) |
a695cb58 SRRH |
6598 | goto out_unlock; |
6599 | ||
0c8916c3 SR |
6600 | list_del(&tr->list); |
6601 | ||
6b450d25 | 6602 | tracing_set_nop(tr); |
0c8916c3 | 6603 | event_trace_del_tracer(tr); |
591dffda | 6604 | ftrace_destroy_function_files(tr); |
0c8916c3 | 6605 | debugfs_remove_recursive(tr->dir); |
a9fcaaac | 6606 | free_trace_buffers(tr); |
0c8916c3 SR |
6607 | |
6608 | kfree(tr->name); | |
6609 | kfree(tr); | |
6610 | ||
6611 | ret = 0; | |
6612 | ||
6613 | out_unlock: | |
6614 | mutex_unlock(&trace_types_lock); | |
6615 | ||
6616 | return ret; | |
6617 | } | |
6618 | ||
277ba044 SR |
6619 | static __init void create_trace_instances(struct dentry *d_tracer) |
6620 | { | |
eae47358 SRRH |
6621 | trace_instance_dir = tracefs_create_instance_dir("instances", d_tracer, |
6622 | instance_mkdir, | |
6623 | instance_rmdir); | |
277ba044 SR |
6624 | if (WARN_ON(!trace_instance_dir)) |
6625 | return; | |
277ba044 SR |
6626 | } |
6627 | ||
2b6080f2 | 6628 | static void |
8434dc93 | 6629 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
2b6080f2 | 6630 | { |
121aaee7 | 6631 | int cpu; |
2b6080f2 | 6632 | |
607e2ea1 SRRH |
6633 | trace_create_file("available_tracers", 0444, d_tracer, |
6634 | tr, &show_traces_fops); | |
6635 | ||
6636 | trace_create_file("current_tracer", 0644, d_tracer, | |
6637 | tr, &set_tracer_fops); | |
6638 | ||
ccfe9e42 AL |
6639 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
6640 | tr, &tracing_cpumask_fops); | |
6641 | ||
2b6080f2 SR |
6642 | trace_create_file("trace_options", 0644, d_tracer, |
6643 | tr, &tracing_iter_fops); | |
6644 | ||
6645 | trace_create_file("trace", 0644, d_tracer, | |
6484c71c | 6646 | tr, &tracing_fops); |
2b6080f2 SR |
6647 | |
6648 | trace_create_file("trace_pipe", 0444, d_tracer, | |
15544209 | 6649 | tr, &tracing_pipe_fops); |
2b6080f2 SR |
6650 | |
6651 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
0bc392ee | 6652 | tr, &tracing_entries_fops); |
2b6080f2 SR |
6653 | |
6654 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
6655 | tr, &tracing_total_entries_fops); | |
6656 | ||
238ae93d | 6657 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
6658 | tr, &tracing_free_buffer_fops); |
6659 | ||
6660 | trace_create_file("trace_marker", 0220, d_tracer, | |
6661 | tr, &tracing_mark_fops); | |
6662 | ||
6663 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
6664 | &trace_clock_fops); | |
6665 | ||
6666 | trace_create_file("tracing_on", 0644, d_tracer, | |
6484c71c | 6667 | tr, &rb_simple_fops); |
ce9bae55 | 6668 | |
6d9b3fa5 SRRH |
6669 | #ifdef CONFIG_TRACER_MAX_TRACE |
6670 | trace_create_file("tracing_max_latency", 0644, d_tracer, | |
6671 | &tr->max_latency, &tracing_max_lat_fops); | |
6672 | #endif | |
6673 | ||
591dffda SRRH |
6674 | if (ftrace_create_function_files(tr, d_tracer)) |
6675 | WARN(1, "Could not allocate function filter files"); | |
6676 | ||
ce9bae55 SRRH |
6677 | #ifdef CONFIG_TRACER_SNAPSHOT |
6678 | trace_create_file("snapshot", 0644, d_tracer, | |
6484c71c | 6679 | tr, &snapshot_fops); |
ce9bae55 | 6680 | #endif |
121aaee7 SRRH |
6681 | |
6682 | for_each_tracing_cpu(cpu) | |
8434dc93 | 6683 | tracing_init_tracefs_percpu(tr, cpu); |
121aaee7 | 6684 | |
2b6080f2 SR |
6685 | } |
6686 | ||
f76180bc SRRH |
6687 | static struct vfsmount *trace_automount(void *ingore) |
6688 | { | |
6689 | struct vfsmount *mnt; | |
6690 | struct file_system_type *type; | |
6691 | ||
6692 | /* | |
6693 | * To maintain backward compatibility for tools that mount | |
6694 | * debugfs to get to the tracing facility, tracefs is automatically | |
6695 | * mounted to the debugfs/tracing directory. | |
6696 | */ | |
6697 | type = get_fs_type("tracefs"); | |
6698 | if (!type) | |
6699 | return NULL; | |
6700 | mnt = vfs_kern_mount(type, 0, "tracefs", NULL); | |
6701 | put_filesystem(type); | |
6702 | if (IS_ERR(mnt)) | |
6703 | return NULL; | |
6704 | mntget(mnt); | |
6705 | ||
6706 | return mnt; | |
6707 | } | |
6708 | ||
7eeafbca SRRH |
6709 | /** |
6710 | * tracing_init_dentry - initialize top level trace array | |
6711 | * | |
6712 | * This is called when creating files or directories in the tracing | |
6713 | * directory. It is called via fs_initcall() by any of the boot up code | |
6714 | * and expects to return the dentry of the top level tracing directory. | |
6715 | */ | |
6716 | struct dentry *tracing_init_dentry(void) | |
6717 | { | |
6718 | struct trace_array *tr = &global_trace; | |
6719 | ||
f76180bc | 6720 | /* The top level trace array uses NULL as parent */ |
7eeafbca | 6721 | if (tr->dir) |
f76180bc | 6722 | return NULL; |
7eeafbca SRRH |
6723 | |
6724 | if (WARN_ON(!debugfs_initialized())) | |
6725 | return ERR_PTR(-ENODEV); | |
6726 | ||
f76180bc SRRH |
6727 | /* |
6728 | * As there may still be users that expect the tracing | |
6729 | * files to exist in debugfs/tracing, we must automount | |
6730 | * the tracefs file system there, so older tools still | |
6731 | * work with the newer kerenl. | |
6732 | */ | |
6733 | tr->dir = debugfs_create_automount("tracing", NULL, | |
6734 | trace_automount, NULL); | |
7eeafbca SRRH |
6735 | if (!tr->dir) { |
6736 | pr_warn_once("Could not create debugfs directory 'tracing'\n"); | |
6737 | return ERR_PTR(-ENOMEM); | |
6738 | } | |
6739 | ||
8434dc93 | 6740 | return NULL; |
7eeafbca SRRH |
6741 | } |
6742 | ||
0c564a53 SRRH |
6743 | extern struct trace_enum_map *__start_ftrace_enum_maps[]; |
6744 | extern struct trace_enum_map *__stop_ftrace_enum_maps[]; | |
6745 | ||
6746 | static void __init trace_enum_init(void) | |
6747 | { | |
3673b8e4 SRRH |
6748 | int len; |
6749 | ||
6750 | len = __stop_ftrace_enum_maps - __start_ftrace_enum_maps; | |
9828413d | 6751 | trace_insert_enum_map(NULL, __start_ftrace_enum_maps, len); |
3673b8e4 SRRH |
6752 | } |
6753 | ||
6754 | #ifdef CONFIG_MODULES | |
6755 | static void trace_module_add_enums(struct module *mod) | |
6756 | { | |
6757 | if (!mod->num_trace_enums) | |
6758 | return; | |
6759 | ||
6760 | /* | |
6761 | * Modules with bad taint do not have events created, do | |
6762 | * not bother with enums either. | |
6763 | */ | |
6764 | if (trace_module_has_bad_taint(mod)) | |
6765 | return; | |
6766 | ||
9828413d | 6767 | trace_insert_enum_map(mod, mod->trace_enums, mod->num_trace_enums); |
3673b8e4 SRRH |
6768 | } |
6769 | ||
9828413d SRRH |
6770 | #ifdef CONFIG_TRACE_ENUM_MAP_FILE |
6771 | static void trace_module_remove_enums(struct module *mod) | |
6772 | { | |
6773 | union trace_enum_map_item *map; | |
6774 | union trace_enum_map_item **last = &trace_enum_maps; | |
6775 | ||
6776 | if (!mod->num_trace_enums) | |
6777 | return; | |
6778 | ||
6779 | mutex_lock(&trace_enum_mutex); | |
6780 | ||
6781 | map = trace_enum_maps; | |
6782 | ||
6783 | while (map) { | |
6784 | if (map->head.mod == mod) | |
6785 | break; | |
6786 | map = trace_enum_jmp_to_tail(map); | |
6787 | last = &map->tail.next; | |
6788 | map = map->tail.next; | |
6789 | } | |
6790 | if (!map) | |
6791 | goto out; | |
6792 | ||
6793 | *last = trace_enum_jmp_to_tail(map)->tail.next; | |
6794 | kfree(map); | |
6795 | out: | |
6796 | mutex_unlock(&trace_enum_mutex); | |
6797 | } | |
6798 | #else | |
6799 | static inline void trace_module_remove_enums(struct module *mod) { } | |
6800 | #endif /* CONFIG_TRACE_ENUM_MAP_FILE */ | |
6801 | ||
3673b8e4 SRRH |
6802 | static int trace_module_notify(struct notifier_block *self, |
6803 | unsigned long val, void *data) | |
6804 | { | |
6805 | struct module *mod = data; | |
6806 | ||
6807 | switch (val) { | |
6808 | case MODULE_STATE_COMING: | |
6809 | trace_module_add_enums(mod); | |
6810 | break; | |
9828413d SRRH |
6811 | case MODULE_STATE_GOING: |
6812 | trace_module_remove_enums(mod); | |
6813 | break; | |
3673b8e4 SRRH |
6814 | } |
6815 | ||
6816 | return 0; | |
0c564a53 SRRH |
6817 | } |
6818 | ||
3673b8e4 SRRH |
6819 | static struct notifier_block trace_module_nb = { |
6820 | .notifier_call = trace_module_notify, | |
6821 | .priority = 0, | |
6822 | }; | |
9828413d | 6823 | #endif /* CONFIG_MODULES */ |
3673b8e4 | 6824 | |
8434dc93 | 6825 | static __init int tracer_init_tracefs(void) |
bc0c38d1 SR |
6826 | { |
6827 | struct dentry *d_tracer; | |
bc0c38d1 | 6828 | |
7e53bd42 LJ |
6829 | trace_access_lock_init(); |
6830 | ||
bc0c38d1 | 6831 | d_tracer = tracing_init_dentry(); |
14a5ae40 | 6832 | if (IS_ERR(d_tracer)) |
ed6f1c99 | 6833 | return 0; |
bc0c38d1 | 6834 | |
8434dc93 | 6835 | init_tracer_tracefs(&global_trace, d_tracer); |
bc0c38d1 | 6836 | |
5452af66 | 6837 | trace_create_file("tracing_thresh", 0644, d_tracer, |
6508fa76 | 6838 | &global_trace, &tracing_thresh_fops); |
a8259075 | 6839 | |
339ae5d3 | 6840 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
6841 | NULL, &tracing_readme_fops); |
6842 | ||
69abe6a5 AP |
6843 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
6844 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 6845 | |
939c7a4f YY |
6846 | trace_create_file("saved_cmdlines_size", 0644, d_tracer, |
6847 | NULL, &tracing_saved_cmdlines_size_fops); | |
6848 | ||
0c564a53 SRRH |
6849 | trace_enum_init(); |
6850 | ||
9828413d SRRH |
6851 | trace_create_enum_file(d_tracer); |
6852 | ||
3673b8e4 SRRH |
6853 | #ifdef CONFIG_MODULES |
6854 | register_module_notifier(&trace_module_nb); | |
6855 | #endif | |
6856 | ||
bc0c38d1 | 6857 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
6858 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
6859 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 6860 | #endif |
b04cc6b1 | 6861 | |
277ba044 | 6862 | create_trace_instances(d_tracer); |
5452af66 | 6863 | |
2b6080f2 | 6864 | create_trace_options_dir(&global_trace); |
b04cc6b1 | 6865 | |
09d23a1d SRRH |
6866 | /* If the tracer was started via cmdline, create options for it here */ |
6867 | if (global_trace.current_trace != &nop_trace) | |
6868 | update_tracer_options(&global_trace, global_trace.current_trace); | |
6869 | ||
b5ad384e | 6870 | return 0; |
bc0c38d1 SR |
6871 | } |
6872 | ||
3f5a54e3 SR |
6873 | static int trace_panic_handler(struct notifier_block *this, |
6874 | unsigned long event, void *unused) | |
6875 | { | |
944ac425 | 6876 | if (ftrace_dump_on_oops) |
cecbca96 | 6877 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6878 | return NOTIFY_OK; |
6879 | } | |
6880 | ||
6881 | static struct notifier_block trace_panic_notifier = { | |
6882 | .notifier_call = trace_panic_handler, | |
6883 | .next = NULL, | |
6884 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
6885 | }; | |
6886 | ||
6887 | static int trace_die_handler(struct notifier_block *self, | |
6888 | unsigned long val, | |
6889 | void *data) | |
6890 | { | |
6891 | switch (val) { | |
6892 | case DIE_OOPS: | |
944ac425 | 6893 | if (ftrace_dump_on_oops) |
cecbca96 | 6894 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6895 | break; |
6896 | default: | |
6897 | break; | |
6898 | } | |
6899 | return NOTIFY_OK; | |
6900 | } | |
6901 | ||
6902 | static struct notifier_block trace_die_notifier = { | |
6903 | .notifier_call = trace_die_handler, | |
6904 | .priority = 200 | |
6905 | }; | |
6906 | ||
6907 | /* | |
6908 | * printk is set to max of 1024, we really don't need it that big. | |
6909 | * Nothing should be printing 1000 characters anyway. | |
6910 | */ | |
6911 | #define TRACE_MAX_PRINT 1000 | |
6912 | ||
6913 | /* | |
6914 | * Define here KERN_TRACE so that we have one place to modify | |
6915 | * it if we decide to change what log level the ftrace dump | |
6916 | * should be at. | |
6917 | */ | |
428aee14 | 6918 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 6919 | |
955b61e5 | 6920 | void |
3f5a54e3 SR |
6921 | trace_printk_seq(struct trace_seq *s) |
6922 | { | |
6923 | /* Probably should print a warning here. */ | |
3a161d99 SRRH |
6924 | if (s->seq.len >= TRACE_MAX_PRINT) |
6925 | s->seq.len = TRACE_MAX_PRINT; | |
3f5a54e3 | 6926 | |
820b75f6 SRRH |
6927 | /* |
6928 | * More paranoid code. Although the buffer size is set to | |
6929 | * PAGE_SIZE, and TRACE_MAX_PRINT is 1000, this is just | |
6930 | * an extra layer of protection. | |
6931 | */ | |
6932 | if (WARN_ON_ONCE(s->seq.len >= s->seq.size)) | |
6933 | s->seq.len = s->seq.size - 1; | |
3f5a54e3 SR |
6934 | |
6935 | /* should be zero ended, but we are paranoid. */ | |
3a161d99 | 6936 | s->buffer[s->seq.len] = 0; |
3f5a54e3 SR |
6937 | |
6938 | printk(KERN_TRACE "%s", s->buffer); | |
6939 | ||
f9520750 | 6940 | trace_seq_init(s); |
3f5a54e3 SR |
6941 | } |
6942 | ||
955b61e5 JW |
6943 | void trace_init_global_iter(struct trace_iterator *iter) |
6944 | { | |
6945 | iter->tr = &global_trace; | |
2b6080f2 | 6946 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 6947 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 6948 | iter->trace_buffer = &global_trace.trace_buffer; |
b2f974d6 CS |
6949 | |
6950 | if (iter->trace && iter->trace->open) | |
6951 | iter->trace->open(iter); | |
6952 | ||
6953 | /* Annotate start of buffers if we had overruns */ | |
6954 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) | |
6955 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
6956 | ||
6957 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ | |
6958 | if (trace_clocks[iter->tr->clock_id].in_ns) | |
6959 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
955b61e5 JW |
6960 | } |
6961 | ||
7fe70b57 | 6962 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 6963 | { |
3f5a54e3 SR |
6964 | /* use static because iter can be a bit big for the stack */ |
6965 | static struct trace_iterator iter; | |
7fe70b57 | 6966 | static atomic_t dump_running; |
cf586b61 | 6967 | unsigned int old_userobj; |
d769041f SR |
6968 | unsigned long flags; |
6969 | int cnt = 0, cpu; | |
3f5a54e3 | 6970 | |
7fe70b57 SRRH |
6971 | /* Only allow one dump user at a time. */ |
6972 | if (atomic_inc_return(&dump_running) != 1) { | |
6973 | atomic_dec(&dump_running); | |
6974 | return; | |
6975 | } | |
3f5a54e3 | 6976 | |
7fe70b57 SRRH |
6977 | /* |
6978 | * Always turn off tracing when we dump. | |
6979 | * We don't need to show trace output of what happens | |
6980 | * between multiple crashes. | |
6981 | * | |
6982 | * If the user does a sysrq-z, then they can re-enable | |
6983 | * tracing with echo 1 > tracing_on. | |
6984 | */ | |
0ee6b6cf | 6985 | tracing_off(); |
cf586b61 | 6986 | |
7fe70b57 | 6987 | local_irq_save(flags); |
3f5a54e3 | 6988 | |
38dbe0b1 | 6989 | /* Simulate the iterator */ |
955b61e5 JW |
6990 | trace_init_global_iter(&iter); |
6991 | ||
d769041f | 6992 | for_each_tracing_cpu(cpu) { |
12883efb | 6993 | atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled); |
d769041f SR |
6994 | } |
6995 | ||
cf586b61 FW |
6996 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
6997 | ||
b54d3de9 TE |
6998 | /* don't look at user memory in panic mode */ |
6999 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
7000 | ||
cecbca96 FW |
7001 | switch (oops_dump_mode) { |
7002 | case DUMP_ALL: | |
ae3b5093 | 7003 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
7004 | break; |
7005 | case DUMP_ORIG: | |
7006 | iter.cpu_file = raw_smp_processor_id(); | |
7007 | break; | |
7008 | case DUMP_NONE: | |
7009 | goto out_enable; | |
7010 | default: | |
7011 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 7012 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
7013 | } |
7014 | ||
7015 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 7016 | |
7fe70b57 SRRH |
7017 | /* Did function tracer already get disabled? */ |
7018 | if (ftrace_is_dead()) { | |
7019 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
7020 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
7021 | } | |
7022 | ||
3f5a54e3 SR |
7023 | /* |
7024 | * We need to stop all tracing on all CPUS to read the | |
7025 | * the next buffer. This is a bit expensive, but is | |
7026 | * not done often. We fill all what we can read, | |
7027 | * and then release the locks again. | |
7028 | */ | |
7029 | ||
3f5a54e3 SR |
7030 | while (!trace_empty(&iter)) { |
7031 | ||
7032 | if (!cnt) | |
7033 | printk(KERN_TRACE "---------------------------------\n"); | |
7034 | ||
7035 | cnt++; | |
7036 | ||
7037 | /* reset all but tr, trace, and overruns */ | |
7038 | memset(&iter.seq, 0, | |
7039 | sizeof(struct trace_iterator) - | |
7040 | offsetof(struct trace_iterator, seq)); | |
7041 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
7042 | iter.pos = -1; | |
7043 | ||
955b61e5 | 7044 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
7045 | int ret; |
7046 | ||
7047 | ret = print_trace_line(&iter); | |
7048 | if (ret != TRACE_TYPE_NO_CONSUME) | |
7049 | trace_consume(&iter); | |
3f5a54e3 | 7050 | } |
b892e5c8 | 7051 | touch_nmi_watchdog(); |
3f5a54e3 SR |
7052 | |
7053 | trace_printk_seq(&iter.seq); | |
7054 | } | |
7055 | ||
7056 | if (!cnt) | |
7057 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
7058 | else | |
7059 | printk(KERN_TRACE "---------------------------------\n"); | |
7060 | ||
cecbca96 | 7061 | out_enable: |
7fe70b57 | 7062 | trace_flags |= old_userobj; |
cf586b61 | 7063 | |
7fe70b57 SRRH |
7064 | for_each_tracing_cpu(cpu) { |
7065 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); | |
cf586b61 | 7066 | } |
7fe70b57 | 7067 | atomic_dec(&dump_running); |
cd891ae0 | 7068 | local_irq_restore(flags); |
3f5a54e3 | 7069 | } |
a8eecf22 | 7070 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 7071 | |
3928a8a2 | 7072 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 7073 | { |
73c5162a | 7074 | int ring_buf_size; |
9e01c1b7 | 7075 | int ret = -ENOMEM; |
4c11d7ae | 7076 | |
9e01c1b7 RR |
7077 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
7078 | goto out; | |
7079 | ||
ccfe9e42 | 7080 | if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) |
9e01c1b7 | 7081 | goto out_free_buffer_mask; |
4c11d7ae | 7082 | |
07d777fe SR |
7083 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
7084 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 7085 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
7086 | trace_printk_init_buffers(); |
7087 | ||
73c5162a SR |
7088 | /* To save memory, keep the ring buffer size to its minimum */ |
7089 | if (ring_buffer_expanded) | |
7090 | ring_buf_size = trace_buf_size; | |
7091 | else | |
7092 | ring_buf_size = 1; | |
7093 | ||
9e01c1b7 | 7094 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
ccfe9e42 | 7095 | cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); |
9e01c1b7 | 7096 | |
2b6080f2 SR |
7097 | raw_spin_lock_init(&global_trace.start_lock); |
7098 | ||
2c4a33ab SRRH |
7099 | /* Used for event triggers */ |
7100 | temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); | |
7101 | if (!temp_buffer) | |
7102 | goto out_free_cpumask; | |
7103 | ||
939c7a4f YY |
7104 | if (trace_create_savedcmd() < 0) |
7105 | goto out_free_temp_buffer; | |
7106 | ||
9e01c1b7 | 7107 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 7108 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
7109 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
7110 | WARN_ON(1); | |
939c7a4f | 7111 | goto out_free_savedcmd; |
4c11d7ae | 7112 | } |
a7603ff4 | 7113 | |
499e5470 SR |
7114 | if (global_trace.buffer_disabled) |
7115 | tracing_off(); | |
4c11d7ae | 7116 | |
e1e232ca SR |
7117 | if (trace_boot_clock) { |
7118 | ret = tracing_set_clock(&global_trace, trace_boot_clock); | |
7119 | if (ret < 0) | |
7120 | pr_warning("Trace clock %s not defined, going back to default\n", | |
7121 | trace_boot_clock); | |
7122 | } | |
7123 | ||
ca164318 SRRH |
7124 | /* |
7125 | * register_tracer() might reference current_trace, so it | |
7126 | * needs to be set before we register anything. This is | |
7127 | * just a bootstrap of current_trace anyway. | |
7128 | */ | |
2b6080f2 SR |
7129 | global_trace.current_trace = &nop_trace; |
7130 | ||
0b9b12c1 SRRH |
7131 | global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
7132 | ||
4104d326 SRRH |
7133 | ftrace_init_global_array_ops(&global_trace); |
7134 | ||
ca164318 SRRH |
7135 | register_tracer(&nop_trace); |
7136 | ||
60a11774 SR |
7137 | /* All seems OK, enable tracing */ |
7138 | tracing_disabled = 0; | |
3928a8a2 | 7139 | |
3f5a54e3 SR |
7140 | atomic_notifier_chain_register(&panic_notifier_list, |
7141 | &trace_panic_notifier); | |
7142 | ||
7143 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 7144 | |
ae63b31e SR |
7145 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
7146 | ||
7147 | INIT_LIST_HEAD(&global_trace.systems); | |
7148 | INIT_LIST_HEAD(&global_trace.events); | |
7149 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
7150 | ||
7bcfaf54 SR |
7151 | while (trace_boot_options) { |
7152 | char *option; | |
7153 | ||
7154 | option = strsep(&trace_boot_options, ","); | |
2b6080f2 | 7155 | trace_set_options(&global_trace, option); |
7bcfaf54 SR |
7156 | } |
7157 | ||
77fd5c15 SRRH |
7158 | register_snapshot_cmd(); |
7159 | ||
2fc1dfbe | 7160 | return 0; |
3f5a54e3 | 7161 | |
939c7a4f YY |
7162 | out_free_savedcmd: |
7163 | free_saved_cmdlines_buffer(savedcmd); | |
2c4a33ab SRRH |
7164 | out_free_temp_buffer: |
7165 | ring_buffer_free(temp_buffer); | |
9e01c1b7 | 7166 | out_free_cpumask: |
ccfe9e42 | 7167 | free_cpumask_var(global_trace.tracing_cpumask); |
9e01c1b7 RR |
7168 | out_free_buffer_mask: |
7169 | free_cpumask_var(tracing_buffer_mask); | |
7170 | out: | |
7171 | return ret; | |
bc0c38d1 | 7172 | } |
b2821ae6 | 7173 | |
5f893b26 SRRH |
7174 | void __init trace_init(void) |
7175 | { | |
0daa2302 SRRH |
7176 | if (tracepoint_printk) { |
7177 | tracepoint_print_iter = | |
7178 | kmalloc(sizeof(*tracepoint_print_iter), GFP_KERNEL); | |
7179 | if (WARN_ON(!tracepoint_print_iter)) | |
7180 | tracepoint_printk = 0; | |
7181 | } | |
5f893b26 | 7182 | tracer_alloc_buffers(); |
0c564a53 | 7183 | trace_event_init(); |
5f893b26 SRRH |
7184 | } |
7185 | ||
b2821ae6 SR |
7186 | __init static int clear_boot_tracer(void) |
7187 | { | |
7188 | /* | |
7189 | * The default tracer at boot buffer is an init section. | |
7190 | * This function is called in lateinit. If we did not | |
7191 | * find the boot tracer, then clear it out, to prevent | |
7192 | * later registration from accessing the buffer that is | |
7193 | * about to be freed. | |
7194 | */ | |
7195 | if (!default_bootup_tracer) | |
7196 | return 0; | |
7197 | ||
7198 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
7199 | default_bootup_tracer); | |
7200 | default_bootup_tracer = NULL; | |
7201 | ||
7202 | return 0; | |
7203 | } | |
7204 | ||
8434dc93 | 7205 | fs_initcall(tracer_init_tracefs); |
b2821ae6 | 7206 | late_initcall(clear_boot_tracer); |