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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> |
4c11d7ae | 23 | #include <linux/pagemap.h> |
bc0c38d1 SR |
24 | #include <linux/hardirq.h> |
25 | #include <linux/linkage.h> | |
26 | #include <linux/uaccess.h> | |
2cadf913 | 27 | #include <linux/kprobes.h> |
bc0c38d1 SR |
28 | #include <linux/ftrace.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/percpu.h> | |
2cadf913 | 31 | #include <linux/splice.h> |
3f5a54e3 | 32 | #include <linux/kdebug.h> |
5f0c6c03 | 33 | #include <linux/string.h> |
7e53bd42 | 34 | #include <linux/rwsem.h> |
5a0e3ad6 | 35 | #include <linux/slab.h> |
bc0c38d1 SR |
36 | #include <linux/ctype.h> |
37 | #include <linux/init.h> | |
2a2cc8f7 | 38 | #include <linux/poll.h> |
b892e5c8 | 39 | #include <linux/nmi.h> |
bc0c38d1 | 40 | #include <linux/fs.h> |
8bd75c77 | 41 | #include <linux/sched/rt.h> |
86387f7e | 42 | |
bc0c38d1 | 43 | #include "trace.h" |
f0868d1e | 44 | #include "trace_output.h" |
bc0c38d1 | 45 | |
73c5162a SR |
46 | /* |
47 | * On boot up, the ring buffer is set to the minimum size, so that | |
48 | * we do not waste memory on systems that are not using tracing. | |
49 | */ | |
55034cd6 | 50 | bool ring_buffer_expanded; |
73c5162a | 51 | |
8e1b82e0 FW |
52 | /* |
53 | * We need to change this state when a selftest is running. | |
ff32504f FW |
54 | * A selftest will lurk into the ring-buffer to count the |
55 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 56 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
57 | * at the same time, giving false positive or negative results. |
58 | */ | |
8e1b82e0 | 59 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 60 | |
b2821ae6 SR |
61 | /* |
62 | * If a tracer is running, we do not want to run SELFTEST. | |
63 | */ | |
020e5f85 | 64 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 65 | |
adf9f195 FW |
66 | /* For tracers that don't implement custom flags */ |
67 | static struct tracer_opt dummy_tracer_opt[] = { | |
68 | { } | |
69 | }; | |
70 | ||
71 | static struct tracer_flags dummy_tracer_flags = { | |
72 | .val = 0, | |
73 | .opts = dummy_tracer_opt | |
74 | }; | |
75 | ||
8c1a49ae SRRH |
76 | static int |
77 | dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) | |
adf9f195 FW |
78 | { |
79 | return 0; | |
80 | } | |
0f048701 | 81 | |
7ffbd48d SR |
82 | /* |
83 | * To prevent the comm cache from being overwritten when no | |
84 | * tracing is active, only save the comm when a trace event | |
85 | * occurred. | |
86 | */ | |
87 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
88 | ||
0f048701 SR |
89 | /* |
90 | * Kill all tracing for good (never come back). | |
91 | * It is initialized to 1 but will turn to zero if the initialization | |
92 | * of the tracer is successful. But that is the only place that sets | |
93 | * this back to zero. | |
94 | */ | |
4fd27358 | 95 | static int tracing_disabled = 1; |
0f048701 | 96 | |
9288f99a | 97 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 98 | |
955b61e5 | 99 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 100 | |
944ac425 SR |
101 | /* |
102 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
103 | * | |
104 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
105 | * is set, then ftrace_dump is called. This will output the contents | |
106 | * of the ftrace buffers to the console. This is very useful for | |
107 | * capturing traces that lead to crashes and outputing it to a | |
108 | * serial console. | |
109 | * | |
110 | * It is default off, but you can enable it with either specifying | |
111 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
112 | * /proc/sys/kernel/ftrace_dump_on_oops |
113 | * Set 1 if you want to dump buffers of all CPUs | |
114 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 115 | */ |
cecbca96 FW |
116 | |
117 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 118 | |
de7edd31 SRRH |
119 | /* When set, tracing will stop when a WARN*() is hit */ |
120 | int __disable_trace_on_warning; | |
121 | ||
b2821ae6 SR |
122 | static int tracing_set_tracer(const char *buf); |
123 | ||
ee6c2c1b LZ |
124 | #define MAX_TRACER_SIZE 100 |
125 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 126 | static char *default_bootup_tracer; |
d9e54076 | 127 | |
55034cd6 SRRH |
128 | static bool allocate_snapshot; |
129 | ||
1beee96b | 130 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 131 | { |
67012ab1 | 132 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 133 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 134 | /* We are using ftrace early, expand it */ |
55034cd6 | 135 | ring_buffer_expanded = true; |
d9e54076 PZ |
136 | return 1; |
137 | } | |
1beee96b | 138 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 139 | |
944ac425 SR |
140 | static int __init set_ftrace_dump_on_oops(char *str) |
141 | { | |
cecbca96 FW |
142 | if (*str++ != '=' || !*str) { |
143 | ftrace_dump_on_oops = DUMP_ALL; | |
144 | return 1; | |
145 | } | |
146 | ||
147 | if (!strcmp("orig_cpu", str)) { | |
148 | ftrace_dump_on_oops = DUMP_ORIG; | |
149 | return 1; | |
150 | } | |
151 | ||
152 | return 0; | |
944ac425 SR |
153 | } |
154 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 155 | |
de7edd31 SRRH |
156 | static int __init stop_trace_on_warning(char *str) |
157 | { | |
158 | __disable_trace_on_warning = 1; | |
159 | return 1; | |
160 | } | |
161 | __setup("traceoff_on_warning=", stop_trace_on_warning); | |
162 | ||
3209cff4 | 163 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
164 | { |
165 | allocate_snapshot = true; | |
166 | /* We also need the main ring buffer expanded */ | |
167 | ring_buffer_expanded = true; | |
168 | return 1; | |
169 | } | |
3209cff4 | 170 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 171 | |
7bcfaf54 SR |
172 | |
173 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
174 | static char *trace_boot_options __initdata; | |
175 | ||
176 | static int __init set_trace_boot_options(char *str) | |
177 | { | |
67012ab1 | 178 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
179 | trace_boot_options = trace_boot_options_buf; |
180 | return 0; | |
181 | } | |
182 | __setup("trace_options=", set_trace_boot_options); | |
183 | ||
de7edd31 | 184 | |
cf8e3474 | 185 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
186 | { |
187 | nsec += 500; | |
188 | do_div(nsec, 1000); | |
189 | return nsec; | |
190 | } | |
191 | ||
4fcdae83 SR |
192 | /* |
193 | * The global_trace is the descriptor that holds the tracing | |
194 | * buffers for the live tracing. For each CPU, it contains | |
195 | * a link list of pages that will store trace entries. The | |
196 | * page descriptor of the pages in the memory is used to hold | |
197 | * the link list by linking the lru item in the page descriptor | |
198 | * to each of the pages in the buffer per CPU. | |
199 | * | |
200 | * For each active CPU there is a data field that holds the | |
201 | * pages for the buffer for that CPU. Each CPU has the same number | |
202 | * of pages allocated for its buffer. | |
203 | */ | |
bc0c38d1 SR |
204 | static struct trace_array global_trace; |
205 | ||
ae63b31e | 206 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 207 | |
ff451961 SRRH |
208 | int trace_array_get(struct trace_array *this_tr) |
209 | { | |
210 | struct trace_array *tr; | |
211 | int ret = -ENODEV; | |
212 | ||
213 | mutex_lock(&trace_types_lock); | |
214 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
215 | if (tr == this_tr) { | |
216 | tr->ref++; | |
217 | ret = 0; | |
218 | break; | |
219 | } | |
220 | } | |
221 | mutex_unlock(&trace_types_lock); | |
222 | ||
223 | return ret; | |
224 | } | |
225 | ||
226 | static void __trace_array_put(struct trace_array *this_tr) | |
227 | { | |
228 | WARN_ON(!this_tr->ref); | |
229 | this_tr->ref--; | |
230 | } | |
231 | ||
232 | void trace_array_put(struct trace_array *this_tr) | |
233 | { | |
234 | mutex_lock(&trace_types_lock); | |
235 | __trace_array_put(this_tr); | |
236 | mutex_unlock(&trace_types_lock); | |
237 | } | |
238 | ||
f306cc82 TZ |
239 | int filter_check_discard(struct ftrace_event_file *file, void *rec, |
240 | struct ring_buffer *buffer, | |
241 | struct ring_buffer_event *event) | |
eb02ce01 | 242 | { |
f306cc82 TZ |
243 | if (unlikely(file->flags & FTRACE_EVENT_FL_FILTERED) && |
244 | !filter_match_preds(file->filter, rec)) { | |
245 | ring_buffer_discard_commit(buffer, event); | |
246 | return 1; | |
247 | } | |
248 | ||
249 | return 0; | |
250 | } | |
251 | EXPORT_SYMBOL_GPL(filter_check_discard); | |
252 | ||
253 | int call_filter_check_discard(struct ftrace_event_call *call, void *rec, | |
254 | struct ring_buffer *buffer, | |
255 | struct ring_buffer_event *event) | |
256 | { | |
257 | if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && | |
258 | !filter_match_preds(call->filter, rec)) { | |
259 | ring_buffer_discard_commit(buffer, event); | |
260 | return 1; | |
261 | } | |
262 | ||
263 | return 0; | |
eb02ce01 | 264 | } |
f306cc82 | 265 | EXPORT_SYMBOL_GPL(call_filter_check_discard); |
eb02ce01 | 266 | |
9457158b | 267 | cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) |
37886f6a SR |
268 | { |
269 | u64 ts; | |
270 | ||
271 | /* Early boot up does not have a buffer yet */ | |
9457158b | 272 | if (!buf->buffer) |
37886f6a SR |
273 | return trace_clock_local(); |
274 | ||
9457158b AL |
275 | ts = ring_buffer_time_stamp(buf->buffer, cpu); |
276 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); | |
37886f6a SR |
277 | |
278 | return ts; | |
279 | } | |
bc0c38d1 | 280 | |
9457158b AL |
281 | cycle_t ftrace_now(int cpu) |
282 | { | |
283 | return buffer_ftrace_now(&global_trace.trace_buffer, cpu); | |
284 | } | |
285 | ||
10246fa3 SRRH |
286 | /** |
287 | * tracing_is_enabled - Show if global_trace has been disabled | |
288 | * | |
289 | * Shows if the global trace has been enabled or not. It uses the | |
290 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
291 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
292 | * need to know the accurate state, use tracing_is_on() which is a little | |
293 | * slower, but accurate. | |
294 | */ | |
9036990d SR |
295 | int tracing_is_enabled(void) |
296 | { | |
10246fa3 SRRH |
297 | /* |
298 | * For quick access (irqsoff uses this in fast path), just | |
299 | * return the mirror variable of the state of the ring buffer. | |
300 | * It's a little racy, but we don't really care. | |
301 | */ | |
302 | smp_rmb(); | |
303 | return !global_trace.buffer_disabled; | |
9036990d SR |
304 | } |
305 | ||
4fcdae83 | 306 | /* |
3928a8a2 SR |
307 | * trace_buf_size is the size in bytes that is allocated |
308 | * for a buffer. Note, the number of bytes is always rounded | |
309 | * to page size. | |
3f5a54e3 SR |
310 | * |
311 | * This number is purposely set to a low number of 16384. | |
312 | * If the dump on oops happens, it will be much appreciated | |
313 | * to not have to wait for all that output. Anyway this can be | |
314 | * boot time and run time configurable. | |
4fcdae83 | 315 | */ |
3928a8a2 | 316 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 317 | |
3928a8a2 | 318 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 319 | |
4fcdae83 | 320 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 321 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 322 | |
4fcdae83 SR |
323 | /* |
324 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 325 | */ |
a8227415 | 326 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 327 | |
7e53bd42 LJ |
328 | /* |
329 | * serialize the access of the ring buffer | |
330 | * | |
331 | * ring buffer serializes readers, but it is low level protection. | |
332 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
333 | * are not protected by ring buffer. | |
334 | * | |
335 | * The content of events may become garbage if we allow other process consumes | |
336 | * these events concurrently: | |
337 | * A) the page of the consumed events may become a normal page | |
338 | * (not reader page) in ring buffer, and this page will be rewrited | |
339 | * by events producer. | |
340 | * B) The page of the consumed events may become a page for splice_read, | |
341 | * and this page will be returned to system. | |
342 | * | |
343 | * These primitives allow multi process access to different cpu ring buffer | |
344 | * concurrently. | |
345 | * | |
346 | * These primitives don't distinguish read-only and read-consume access. | |
347 | * Multi read-only access are also serialized. | |
348 | */ | |
349 | ||
350 | #ifdef CONFIG_SMP | |
351 | static DECLARE_RWSEM(all_cpu_access_lock); | |
352 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
353 | ||
354 | static inline void trace_access_lock(int cpu) | |
355 | { | |
ae3b5093 | 356 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
357 | /* gain it for accessing the whole ring buffer. */ |
358 | down_write(&all_cpu_access_lock); | |
359 | } else { | |
360 | /* gain it for accessing a cpu ring buffer. */ | |
361 | ||
ae3b5093 | 362 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
363 | down_read(&all_cpu_access_lock); |
364 | ||
365 | /* Secondly block other access to this @cpu ring buffer. */ | |
366 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
367 | } | |
368 | } | |
369 | ||
370 | static inline void trace_access_unlock(int cpu) | |
371 | { | |
ae3b5093 | 372 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
373 | up_write(&all_cpu_access_lock); |
374 | } else { | |
375 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
376 | up_read(&all_cpu_access_lock); | |
377 | } | |
378 | } | |
379 | ||
380 | static inline void trace_access_lock_init(void) | |
381 | { | |
382 | int cpu; | |
383 | ||
384 | for_each_possible_cpu(cpu) | |
385 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
386 | } | |
387 | ||
388 | #else | |
389 | ||
390 | static DEFINE_MUTEX(access_lock); | |
391 | ||
392 | static inline void trace_access_lock(int cpu) | |
393 | { | |
394 | (void)cpu; | |
395 | mutex_lock(&access_lock); | |
396 | } | |
397 | ||
398 | static inline void trace_access_unlock(int cpu) | |
399 | { | |
400 | (void)cpu; | |
401 | mutex_unlock(&access_lock); | |
402 | } | |
403 | ||
404 | static inline void trace_access_lock_init(void) | |
405 | { | |
406 | } | |
407 | ||
408 | #endif | |
409 | ||
ee6bce52 | 410 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 411 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 412 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 | 413 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
328df475 | 414 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION; |
e7e2ee89 | 415 | |
5280bcef | 416 | static void tracer_tracing_on(struct trace_array *tr) |
10246fa3 SRRH |
417 | { |
418 | if (tr->trace_buffer.buffer) | |
419 | ring_buffer_record_on(tr->trace_buffer.buffer); | |
420 | /* | |
421 | * This flag is looked at when buffers haven't been allocated | |
422 | * yet, or by some tracers (like irqsoff), that just want to | |
423 | * know if the ring buffer has been disabled, but it can handle | |
424 | * races of where it gets disabled but we still do a record. | |
425 | * As the check is in the fast path of the tracers, it is more | |
426 | * important to be fast than accurate. | |
427 | */ | |
428 | tr->buffer_disabled = 0; | |
429 | /* Make the flag seen by readers */ | |
430 | smp_wmb(); | |
431 | } | |
432 | ||
499e5470 SR |
433 | /** |
434 | * tracing_on - enable tracing buffers | |
435 | * | |
436 | * This function enables tracing buffers that may have been | |
437 | * disabled with tracing_off. | |
438 | */ | |
439 | void tracing_on(void) | |
440 | { | |
10246fa3 | 441 | tracer_tracing_on(&global_trace); |
499e5470 SR |
442 | } |
443 | EXPORT_SYMBOL_GPL(tracing_on); | |
444 | ||
09ae7234 SRRH |
445 | /** |
446 | * __trace_puts - write a constant string into the trace buffer. | |
447 | * @ip: The address of the caller | |
448 | * @str: The constant string to write | |
449 | * @size: The size of the string. | |
450 | */ | |
451 | int __trace_puts(unsigned long ip, const char *str, int size) | |
452 | { | |
453 | struct ring_buffer_event *event; | |
454 | struct ring_buffer *buffer; | |
455 | struct print_entry *entry; | |
456 | unsigned long irq_flags; | |
457 | int alloc; | |
458 | ||
3132e107 SRRH |
459 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
460 | return 0; | |
461 | ||
09ae7234 SRRH |
462 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ |
463 | ||
464 | local_save_flags(irq_flags); | |
465 | buffer = global_trace.trace_buffer.buffer; | |
466 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, | |
467 | irq_flags, preempt_count()); | |
468 | if (!event) | |
469 | return 0; | |
470 | ||
471 | entry = ring_buffer_event_data(event); | |
472 | entry->ip = ip; | |
473 | ||
474 | memcpy(&entry->buf, str, size); | |
475 | ||
476 | /* Add a newline if necessary */ | |
477 | if (entry->buf[size - 1] != '\n') { | |
478 | entry->buf[size] = '\n'; | |
479 | entry->buf[size + 1] = '\0'; | |
480 | } else | |
481 | entry->buf[size] = '\0'; | |
482 | ||
483 | __buffer_unlock_commit(buffer, event); | |
484 | ||
485 | return size; | |
486 | } | |
487 | EXPORT_SYMBOL_GPL(__trace_puts); | |
488 | ||
489 | /** | |
490 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
491 | * @ip: The address of the caller | |
492 | * @str: The constant string to write to the buffer to | |
493 | */ | |
494 | int __trace_bputs(unsigned long ip, const char *str) | |
495 | { | |
496 | struct ring_buffer_event *event; | |
497 | struct ring_buffer *buffer; | |
498 | struct bputs_entry *entry; | |
499 | unsigned long irq_flags; | |
500 | int size = sizeof(struct bputs_entry); | |
501 | ||
3132e107 SRRH |
502 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
503 | return 0; | |
504 | ||
09ae7234 SRRH |
505 | local_save_flags(irq_flags); |
506 | buffer = global_trace.trace_buffer.buffer; | |
507 | event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, | |
508 | irq_flags, preempt_count()); | |
509 | if (!event) | |
510 | return 0; | |
511 | ||
512 | entry = ring_buffer_event_data(event); | |
513 | entry->ip = ip; | |
514 | entry->str = str; | |
515 | ||
516 | __buffer_unlock_commit(buffer, event); | |
517 | ||
518 | return 1; | |
519 | } | |
520 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
521 | ||
ad909e21 SRRH |
522 | #ifdef CONFIG_TRACER_SNAPSHOT |
523 | /** | |
524 | * trace_snapshot - take a snapshot of the current buffer. | |
525 | * | |
526 | * This causes a swap between the snapshot buffer and the current live | |
527 | * tracing buffer. You can use this to take snapshots of the live | |
528 | * trace when some condition is triggered, but continue to trace. | |
529 | * | |
530 | * Note, make sure to allocate the snapshot with either | |
531 | * a tracing_snapshot_alloc(), or by doing it manually | |
532 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
533 | * | |
534 | * If the snapshot buffer is not allocated, it will stop tracing. | |
535 | * Basically making a permanent snapshot. | |
536 | */ | |
537 | void tracing_snapshot(void) | |
538 | { | |
539 | struct trace_array *tr = &global_trace; | |
540 | struct tracer *tracer = tr->current_trace; | |
541 | unsigned long flags; | |
542 | ||
1b22e382 SRRH |
543 | if (in_nmi()) { |
544 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
545 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
546 | return; | |
547 | } | |
548 | ||
ad909e21 | 549 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
550 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
551 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
552 | tracing_off(); |
553 | return; | |
554 | } | |
555 | ||
556 | /* Note, snapshot can not be used when the tracer uses it */ | |
557 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
558 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
559 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
560 | return; |
561 | } | |
562 | ||
563 | local_irq_save(flags); | |
564 | update_max_tr(tr, current, smp_processor_id()); | |
565 | local_irq_restore(flags); | |
566 | } | |
1b22e382 | 567 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
568 | |
569 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
570 | struct trace_buffer *size_buf, int cpu_id); | |
3209cff4 SRRH |
571 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); |
572 | ||
573 | static int alloc_snapshot(struct trace_array *tr) | |
574 | { | |
575 | int ret; | |
576 | ||
577 | if (!tr->allocated_snapshot) { | |
578 | ||
579 | /* allocate spare buffer */ | |
580 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
581 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
582 | if (ret < 0) | |
583 | return ret; | |
584 | ||
585 | tr->allocated_snapshot = true; | |
586 | } | |
587 | ||
588 | return 0; | |
589 | } | |
590 | ||
591 | void free_snapshot(struct trace_array *tr) | |
592 | { | |
593 | /* | |
594 | * We don't free the ring buffer. instead, resize it because | |
595 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
596 | * we want preserve it. | |
597 | */ | |
598 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
599 | set_buffer_entries(&tr->max_buffer, 1); | |
600 | tracing_reset_online_cpus(&tr->max_buffer); | |
601 | tr->allocated_snapshot = false; | |
602 | } | |
ad909e21 | 603 | |
93e31ffb TZ |
604 | /** |
605 | * tracing_alloc_snapshot - allocate snapshot buffer. | |
606 | * | |
607 | * This only allocates the snapshot buffer if it isn't already | |
608 | * allocated - it doesn't also take a snapshot. | |
609 | * | |
610 | * This is meant to be used in cases where the snapshot buffer needs | |
611 | * to be set up for events that can't sleep but need to be able to | |
612 | * trigger a snapshot. | |
613 | */ | |
614 | int tracing_alloc_snapshot(void) | |
615 | { | |
616 | struct trace_array *tr = &global_trace; | |
617 | int ret; | |
618 | ||
619 | ret = alloc_snapshot(tr); | |
620 | WARN_ON(ret < 0); | |
621 | ||
622 | return ret; | |
623 | } | |
624 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
625 | ||
ad909e21 SRRH |
626 | /** |
627 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
628 | * | |
629 | * This is similar to trace_snapshot(), but it will allocate the | |
630 | * snapshot buffer if it isn't already allocated. Use this only | |
631 | * where it is safe to sleep, as the allocation may sleep. | |
632 | * | |
633 | * This causes a swap between the snapshot buffer and the current live | |
634 | * tracing buffer. You can use this to take snapshots of the live | |
635 | * trace when some condition is triggered, but continue to trace. | |
636 | */ | |
637 | void tracing_snapshot_alloc(void) | |
638 | { | |
ad909e21 SRRH |
639 | int ret; |
640 | ||
93e31ffb TZ |
641 | ret = tracing_alloc_snapshot(); |
642 | if (ret < 0) | |
3209cff4 | 643 | return; |
ad909e21 SRRH |
644 | |
645 | tracing_snapshot(); | |
646 | } | |
1b22e382 | 647 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
648 | #else |
649 | void tracing_snapshot(void) | |
650 | { | |
651 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
652 | } | |
1b22e382 | 653 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
93e31ffb TZ |
654 | int tracing_alloc_snapshot(void) |
655 | { | |
656 | WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); | |
657 | return -ENODEV; | |
658 | } | |
659 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
ad909e21 SRRH |
660 | void tracing_snapshot_alloc(void) |
661 | { | |
662 | /* Give warning */ | |
663 | tracing_snapshot(); | |
664 | } | |
1b22e382 | 665 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
666 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
667 | ||
5280bcef | 668 | static void tracer_tracing_off(struct trace_array *tr) |
10246fa3 SRRH |
669 | { |
670 | if (tr->trace_buffer.buffer) | |
671 | ring_buffer_record_off(tr->trace_buffer.buffer); | |
672 | /* | |
673 | * This flag is looked at when buffers haven't been allocated | |
674 | * yet, or by some tracers (like irqsoff), that just want to | |
675 | * know if the ring buffer has been disabled, but it can handle | |
676 | * races of where it gets disabled but we still do a record. | |
677 | * As the check is in the fast path of the tracers, it is more | |
678 | * important to be fast than accurate. | |
679 | */ | |
680 | tr->buffer_disabled = 1; | |
681 | /* Make the flag seen by readers */ | |
682 | smp_wmb(); | |
683 | } | |
684 | ||
499e5470 SR |
685 | /** |
686 | * tracing_off - turn off tracing buffers | |
687 | * | |
688 | * This function stops the tracing buffers from recording data. | |
689 | * It does not disable any overhead the tracers themselves may | |
690 | * be causing. This function simply causes all recording to | |
691 | * the ring buffers to fail. | |
692 | */ | |
693 | void tracing_off(void) | |
694 | { | |
10246fa3 | 695 | tracer_tracing_off(&global_trace); |
499e5470 SR |
696 | } |
697 | EXPORT_SYMBOL_GPL(tracing_off); | |
698 | ||
de7edd31 SRRH |
699 | void disable_trace_on_warning(void) |
700 | { | |
701 | if (__disable_trace_on_warning) | |
702 | tracing_off(); | |
703 | } | |
704 | ||
10246fa3 SRRH |
705 | /** |
706 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
707 | * @tr : the trace array to know if ring buffer is enabled | |
708 | * | |
709 | * Shows real state of the ring buffer if it is enabled or not. | |
710 | */ | |
5280bcef | 711 | static int tracer_tracing_is_on(struct trace_array *tr) |
10246fa3 SRRH |
712 | { |
713 | if (tr->trace_buffer.buffer) | |
714 | return ring_buffer_record_is_on(tr->trace_buffer.buffer); | |
715 | return !tr->buffer_disabled; | |
716 | } | |
717 | ||
499e5470 SR |
718 | /** |
719 | * tracing_is_on - show state of ring buffers enabled | |
720 | */ | |
721 | int tracing_is_on(void) | |
722 | { | |
10246fa3 | 723 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
724 | } |
725 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
726 | ||
3928a8a2 | 727 | static int __init set_buf_size(char *str) |
bc0c38d1 | 728 | { |
3928a8a2 | 729 | unsigned long buf_size; |
c6caeeb1 | 730 | |
bc0c38d1 SR |
731 | if (!str) |
732 | return 0; | |
9d612bef | 733 | buf_size = memparse(str, &str); |
c6caeeb1 | 734 | /* nr_entries can not be zero */ |
9d612bef | 735 | if (buf_size == 0) |
c6caeeb1 | 736 | return 0; |
3928a8a2 | 737 | trace_buf_size = buf_size; |
bc0c38d1 SR |
738 | return 1; |
739 | } | |
3928a8a2 | 740 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 741 | |
0e950173 TB |
742 | static int __init set_tracing_thresh(char *str) |
743 | { | |
87abb3b1 | 744 | unsigned long threshold; |
0e950173 TB |
745 | int ret; |
746 | ||
747 | if (!str) | |
748 | return 0; | |
bcd83ea6 | 749 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
750 | if (ret < 0) |
751 | return 0; | |
87abb3b1 | 752 | tracing_thresh = threshold * 1000; |
0e950173 TB |
753 | return 1; |
754 | } | |
755 | __setup("tracing_thresh=", set_tracing_thresh); | |
756 | ||
57f50be1 SR |
757 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
758 | { | |
759 | return nsecs / 1000; | |
760 | } | |
761 | ||
4fcdae83 | 762 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
763 | static const char *trace_options[] = { |
764 | "print-parent", | |
765 | "sym-offset", | |
766 | "sym-addr", | |
767 | "verbose", | |
f9896bf3 | 768 | "raw", |
5e3ca0ec | 769 | "hex", |
cb0f12aa | 770 | "bin", |
2a2cc8f7 | 771 | "block", |
86387f7e | 772 | "stacktrace", |
5e1607a0 | 773 | "trace_printk", |
b2a866f9 | 774 | "ftrace_preempt", |
9f029e83 | 775 | "branch", |
12ef7d44 | 776 | "annotate", |
02b67518 | 777 | "userstacktrace", |
b54d3de9 | 778 | "sym-userobj", |
66896a85 | 779 | "printk-msg-only", |
c4a8e8be | 780 | "context-info", |
c032ef64 | 781 | "latency-format", |
be6f164a | 782 | "sleep-time", |
a2a16d6a | 783 | "graph-time", |
e870e9a1 | 784 | "record-cmd", |
750912fa | 785 | "overwrite", |
cf30cf67 | 786 | "disable_on_free", |
77271ce4 | 787 | "irq-info", |
5224c3a3 | 788 | "markers", |
328df475 | 789 | "function-trace", |
bc0c38d1 SR |
790 | NULL |
791 | }; | |
792 | ||
5079f326 Z |
793 | static struct { |
794 | u64 (*func)(void); | |
795 | const char *name; | |
8be0709f | 796 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 797 | } trace_clocks[] = { |
8be0709f DS |
798 | { trace_clock_local, "local", 1 }, |
799 | { trace_clock_global, "global", 1 }, | |
800 | { trace_clock_counter, "counter", 0 }, | |
8aacf017 | 801 | { trace_clock_jiffies, "uptime", 1 }, |
76f11917 | 802 | { trace_clock, "perf", 1 }, |
8cbd9cc6 | 803 | ARCH_TRACE_CLOCKS |
5079f326 Z |
804 | }; |
805 | ||
b63f39ea | 806 | /* |
807 | * trace_parser_get_init - gets the buffer for trace parser | |
808 | */ | |
809 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
810 | { | |
811 | memset(parser, 0, sizeof(*parser)); | |
812 | ||
813 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
814 | if (!parser->buffer) | |
815 | return 1; | |
816 | ||
817 | parser->size = size; | |
818 | return 0; | |
819 | } | |
820 | ||
821 | /* | |
822 | * trace_parser_put - frees the buffer for trace parser | |
823 | */ | |
824 | void trace_parser_put(struct trace_parser *parser) | |
825 | { | |
826 | kfree(parser->buffer); | |
827 | } | |
828 | ||
829 | /* | |
830 | * trace_get_user - reads the user input string separated by space | |
831 | * (matched by isspace(ch)) | |
832 | * | |
833 | * For each string found the 'struct trace_parser' is updated, | |
834 | * and the function returns. | |
835 | * | |
836 | * Returns number of bytes read. | |
837 | * | |
838 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
839 | */ | |
840 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
841 | size_t cnt, loff_t *ppos) | |
842 | { | |
843 | char ch; | |
844 | size_t read = 0; | |
845 | ssize_t ret; | |
846 | ||
847 | if (!*ppos) | |
848 | trace_parser_clear(parser); | |
849 | ||
850 | ret = get_user(ch, ubuf++); | |
851 | if (ret) | |
852 | goto out; | |
853 | ||
854 | read++; | |
855 | cnt--; | |
856 | ||
857 | /* | |
858 | * The parser is not finished with the last write, | |
859 | * continue reading the user input without skipping spaces. | |
860 | */ | |
861 | if (!parser->cont) { | |
862 | /* skip white space */ | |
863 | while (cnt && isspace(ch)) { | |
864 | ret = get_user(ch, ubuf++); | |
865 | if (ret) | |
866 | goto out; | |
867 | read++; | |
868 | cnt--; | |
869 | } | |
870 | ||
871 | /* only spaces were written */ | |
872 | if (isspace(ch)) { | |
873 | *ppos += read; | |
874 | ret = read; | |
875 | goto out; | |
876 | } | |
877 | ||
878 | parser->idx = 0; | |
879 | } | |
880 | ||
881 | /* read the non-space input */ | |
882 | while (cnt && !isspace(ch)) { | |
3c235a33 | 883 | if (parser->idx < parser->size - 1) |
b63f39ea | 884 | parser->buffer[parser->idx++] = ch; |
885 | else { | |
886 | ret = -EINVAL; | |
887 | goto out; | |
888 | } | |
889 | ret = get_user(ch, ubuf++); | |
890 | if (ret) | |
891 | goto out; | |
892 | read++; | |
893 | cnt--; | |
894 | } | |
895 | ||
896 | /* We either got finished input or we have to wait for another call. */ | |
897 | if (isspace(ch)) { | |
898 | parser->buffer[parser->idx] = 0; | |
899 | parser->cont = false; | |
057db848 | 900 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 901 | parser->cont = true; |
902 | parser->buffer[parser->idx++] = ch; | |
057db848 SR |
903 | } else { |
904 | ret = -EINVAL; | |
905 | goto out; | |
b63f39ea | 906 | } |
907 | ||
908 | *ppos += read; | |
909 | ret = read; | |
910 | ||
911 | out: | |
912 | return ret; | |
913 | } | |
914 | ||
6c6c2796 PP |
915 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
916 | { | |
917 | int len; | |
918 | int ret; | |
919 | ||
2dc5d12b SR |
920 | if (!cnt) |
921 | return 0; | |
922 | ||
6c6c2796 PP |
923 | if (s->len <= s->readpos) |
924 | return -EBUSY; | |
925 | ||
926 | len = s->len - s->readpos; | |
927 | if (cnt > len) | |
928 | cnt = len; | |
929 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 930 | if (ret == cnt) |
6c6c2796 PP |
931 | return -EFAULT; |
932 | ||
2dc5d12b SR |
933 | cnt -= ret; |
934 | ||
e74da523 | 935 | s->readpos += cnt; |
6c6c2796 | 936 | return cnt; |
214023c3 SR |
937 | } |
938 | ||
b8b94265 | 939 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
940 | { |
941 | int len; | |
3c56819b EGM |
942 | |
943 | if (s->len <= s->readpos) | |
944 | return -EBUSY; | |
945 | ||
946 | len = s->len - s->readpos; | |
947 | if (cnt > len) | |
948 | cnt = len; | |
5a26c8f0 | 949 | memcpy(buf, s->buffer + s->readpos, cnt); |
3c56819b | 950 | |
e74da523 | 951 | s->readpos += cnt; |
3c56819b EGM |
952 | return cnt; |
953 | } | |
954 | ||
5d4a9dba SR |
955 | /* |
956 | * ftrace_max_lock is used to protect the swapping of buffers | |
957 | * when taking a max snapshot. The buffers themselves are | |
958 | * protected by per_cpu spinlocks. But the action of the swap | |
959 | * needs its own lock. | |
960 | * | |
445c8951 | 961 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
962 | * with performance when lockdep debugging is enabled. |
963 | * | |
964 | * It is also used in other places outside the update_max_tr | |
965 | * so it needs to be defined outside of the | |
966 | * CONFIG_TRACER_MAX_TRACE. | |
967 | */ | |
445c8951 | 968 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 969 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba | 970 | |
0e950173 TB |
971 | unsigned long __read_mostly tracing_thresh; |
972 | ||
5d4a9dba SR |
973 | #ifdef CONFIG_TRACER_MAX_TRACE |
974 | unsigned long __read_mostly tracing_max_latency; | |
5d4a9dba SR |
975 | |
976 | /* | |
977 | * Copy the new maximum trace into the separate maximum-trace | |
978 | * structure. (this way the maximum trace is permanently saved, | |
979 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
980 | */ | |
981 | static void | |
982 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
983 | { | |
12883efb SRRH |
984 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
985 | struct trace_buffer *max_buf = &tr->max_buffer; | |
986 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
987 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 988 | |
12883efb SRRH |
989 | max_buf->cpu = cpu; |
990 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 991 | |
8248ac05 SR |
992 | max_data->saved_latency = tracing_max_latency; |
993 | max_data->critical_start = data->critical_start; | |
994 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 995 | |
1acaa1b2 | 996 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 997 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
998 | /* |
999 | * If tsk == current, then use current_uid(), as that does not use | |
1000 | * RCU. The irq tracer can be called out of RCU scope. | |
1001 | */ | |
1002 | if (tsk == current) | |
1003 | max_data->uid = current_uid(); | |
1004 | else | |
1005 | max_data->uid = task_uid(tsk); | |
1006 | ||
8248ac05 SR |
1007 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
1008 | max_data->policy = tsk->policy; | |
1009 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
1010 | |
1011 | /* record this tasks comm */ | |
1012 | tracing_record_cmdline(tsk); | |
1013 | } | |
1014 | ||
4fcdae83 SR |
1015 | /** |
1016 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
1017 | * @tr: tracer | |
1018 | * @tsk: the task with the latency | |
1019 | * @cpu: The cpu that initiated the trace. | |
1020 | * | |
1021 | * Flip the buffers between the @tr and the max_tr and record information | |
1022 | * about which task was the cause of this latency. | |
1023 | */ | |
e309b41d | 1024 | void |
bc0c38d1 SR |
1025 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1026 | { | |
2721e72d | 1027 | struct ring_buffer *buf; |
bc0c38d1 | 1028 | |
2b6080f2 | 1029 | if (tr->stop_count) |
b8de7bd1 SR |
1030 | return; |
1031 | ||
4c11d7ae | 1032 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 1033 | |
45ad21ca | 1034 | if (!tr->allocated_snapshot) { |
debdd57f | 1035 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 1036 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 1037 | return; |
debdd57f | 1038 | } |
34600f0e | 1039 | |
0199c4e6 | 1040 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 | 1041 | |
12883efb SRRH |
1042 | buf = tr->trace_buffer.buffer; |
1043 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
1044 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 1045 | |
bc0c38d1 | 1046 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 1047 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
1048 | } |
1049 | ||
1050 | /** | |
1051 | * update_max_tr_single - only copy one trace over, and reset the rest | |
1052 | * @tr - tracer | |
1053 | * @tsk - task with the latency | |
1054 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
1055 | * |
1056 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1057 | */ |
e309b41d | 1058 | void |
bc0c38d1 SR |
1059 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1060 | { | |
3928a8a2 | 1061 | int ret; |
bc0c38d1 | 1062 | |
2b6080f2 | 1063 | if (tr->stop_count) |
b8de7bd1 SR |
1064 | return; |
1065 | ||
4c11d7ae | 1066 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1067 | if (!tr->allocated_snapshot) { |
2930e04d | 1068 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1069 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1070 | return; |
2930e04d | 1071 | } |
ef710e10 | 1072 | |
0199c4e6 | 1073 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 1074 | |
12883efb | 1075 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 1076 | |
e8165dbb SR |
1077 | if (ret == -EBUSY) { |
1078 | /* | |
1079 | * We failed to swap the buffer due to a commit taking | |
1080 | * place on this CPU. We fail to record, but we reset | |
1081 | * the max trace buffer (no one writes directly to it) | |
1082 | * and flag that it failed. | |
1083 | */ | |
12883efb | 1084 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1085 | "Failed to swap buffers due to commit in progress\n"); |
1086 | } | |
1087 | ||
e8165dbb | 1088 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1089 | |
1090 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 1091 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 1092 | } |
5d4a9dba | 1093 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1094 | |
0d5c6e1c SR |
1095 | static void default_wait_pipe(struct trace_iterator *iter) |
1096 | { | |
15693458 SRRH |
1097 | /* Iterators are static, they should be filled or empty */ |
1098 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
1099 | return; | |
0d5c6e1c | 1100 | |
12883efb | 1101 | ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file); |
0d5c6e1c SR |
1102 | } |
1103 | ||
f4e781c0 SRRH |
1104 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
1105 | static int run_tracer_selftest(struct tracer *type) | |
1106 | { | |
1107 | struct trace_array *tr = &global_trace; | |
1108 | struct tracer *saved_tracer = tr->current_trace; | |
1109 | int ret; | |
0d5c6e1c | 1110 | |
f4e781c0 SRRH |
1111 | if (!type->selftest || tracing_selftest_disabled) |
1112 | return 0; | |
0d5c6e1c SR |
1113 | |
1114 | /* | |
f4e781c0 SRRH |
1115 | * Run a selftest on this tracer. |
1116 | * Here we reset the trace buffer, and set the current | |
1117 | * tracer to be this tracer. The tracer can then run some | |
1118 | * internal tracing to verify that everything is in order. | |
1119 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1120 | */ |
f4e781c0 | 1121 | tracing_reset_online_cpus(&tr->trace_buffer); |
0d5c6e1c | 1122 | |
f4e781c0 SRRH |
1123 | tr->current_trace = type; |
1124 | ||
1125 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1126 | if (type->use_max_tr) { | |
1127 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1128 | if (ring_buffer_expanded) | |
1129 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1130 | RING_BUFFER_ALL_CPUS); | |
1131 | tr->allocated_snapshot = true; | |
1132 | } | |
1133 | #endif | |
1134 | ||
1135 | /* the test is responsible for initializing and enabling */ | |
1136 | pr_info("Testing tracer %s: ", type->name); | |
1137 | ret = type->selftest(type, tr); | |
1138 | /* the test is responsible for resetting too */ | |
1139 | tr->current_trace = saved_tracer; | |
1140 | if (ret) { | |
1141 | printk(KERN_CONT "FAILED!\n"); | |
1142 | /* Add the warning after printing 'FAILED' */ | |
1143 | WARN_ON(1); | |
1144 | return -1; | |
1145 | } | |
1146 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1147 | tracing_reset_online_cpus(&tr->trace_buffer); | |
1148 | ||
1149 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1150 | if (type->use_max_tr) { | |
1151 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1152 | |
f4e781c0 SRRH |
1153 | /* Shrink the max buffer again */ |
1154 | if (ring_buffer_expanded) | |
1155 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1156 | RING_BUFFER_ALL_CPUS); | |
1157 | } | |
1158 | #endif | |
1159 | ||
1160 | printk(KERN_CONT "PASSED\n"); | |
1161 | return 0; | |
1162 | } | |
1163 | #else | |
1164 | static inline int run_tracer_selftest(struct tracer *type) | |
1165 | { | |
1166 | return 0; | |
0d5c6e1c | 1167 | } |
f4e781c0 | 1168 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 1169 | |
4fcdae83 SR |
1170 | /** |
1171 | * register_tracer - register a tracer with the ftrace system. | |
1172 | * @type - the plugin for the tracer | |
1173 | * | |
1174 | * Register a new plugin tracer. | |
1175 | */ | |
bc0c38d1 SR |
1176 | int register_tracer(struct tracer *type) |
1177 | { | |
1178 | struct tracer *t; | |
bc0c38d1 SR |
1179 | int ret = 0; |
1180 | ||
1181 | if (!type->name) { | |
1182 | pr_info("Tracer must have a name\n"); | |
1183 | return -1; | |
1184 | } | |
1185 | ||
24a461d5 | 1186 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
1187 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
1188 | return -1; | |
1189 | } | |
1190 | ||
bc0c38d1 | 1191 | mutex_lock(&trace_types_lock); |
86fa2f60 | 1192 | |
8e1b82e0 FW |
1193 | tracing_selftest_running = true; |
1194 | ||
bc0c38d1 SR |
1195 | for (t = trace_types; t; t = t->next) { |
1196 | if (strcmp(type->name, t->name) == 0) { | |
1197 | /* already found */ | |
ee6c2c1b | 1198 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
1199 | type->name); |
1200 | ret = -1; | |
1201 | goto out; | |
1202 | } | |
1203 | } | |
1204 | ||
adf9f195 FW |
1205 | if (!type->set_flag) |
1206 | type->set_flag = &dummy_set_flag; | |
1207 | if (!type->flags) | |
1208 | type->flags = &dummy_tracer_flags; | |
1209 | else | |
1210 | if (!type->flags->opts) | |
1211 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
1212 | if (!type->wait_pipe) |
1213 | type->wait_pipe = default_wait_pipe; | |
1214 | ||
f4e781c0 SRRH |
1215 | ret = run_tracer_selftest(type); |
1216 | if (ret < 0) | |
1217 | goto out; | |
60a11774 | 1218 | |
bc0c38d1 SR |
1219 | type->next = trace_types; |
1220 | trace_types = type; | |
60a11774 | 1221 | |
bc0c38d1 | 1222 | out: |
8e1b82e0 | 1223 | tracing_selftest_running = false; |
bc0c38d1 SR |
1224 | mutex_unlock(&trace_types_lock); |
1225 | ||
dac74940 SR |
1226 | if (ret || !default_bootup_tracer) |
1227 | goto out_unlock; | |
1228 | ||
ee6c2c1b | 1229 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1230 | goto out_unlock; |
1231 | ||
1232 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1233 | /* Do we want this tracer to start on bootup? */ | |
1234 | tracing_set_tracer(type->name); | |
1235 | default_bootup_tracer = NULL; | |
1236 | /* disable other selftests, since this will break it. */ | |
55034cd6 | 1237 | tracing_selftest_disabled = true; |
b2821ae6 | 1238 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1239 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1240 | type->name); | |
b2821ae6 | 1241 | #endif |
b2821ae6 | 1242 | |
dac74940 | 1243 | out_unlock: |
bc0c38d1 SR |
1244 | return ret; |
1245 | } | |
1246 | ||
12883efb | 1247 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1248 | { |
12883efb | 1249 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1250 | |
a5416411 HT |
1251 | if (!buffer) |
1252 | return; | |
1253 | ||
f633903a SR |
1254 | ring_buffer_record_disable(buffer); |
1255 | ||
1256 | /* Make sure all commits have finished */ | |
1257 | synchronize_sched(); | |
68179686 | 1258 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1259 | |
1260 | ring_buffer_record_enable(buffer); | |
1261 | } | |
1262 | ||
12883efb | 1263 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1264 | { |
12883efb | 1265 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1266 | int cpu; |
1267 | ||
a5416411 HT |
1268 | if (!buffer) |
1269 | return; | |
1270 | ||
621968cd SR |
1271 | ring_buffer_record_disable(buffer); |
1272 | ||
1273 | /* Make sure all commits have finished */ | |
1274 | synchronize_sched(); | |
1275 | ||
9457158b | 1276 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 PE |
1277 | |
1278 | for_each_online_cpu(cpu) | |
68179686 | 1279 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1280 | |
1281 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1282 | } |
1283 | ||
09d8091c | 1284 | /* Must have trace_types_lock held */ |
873c642f | 1285 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1286 | { |
873c642f SRRH |
1287 | struct trace_array *tr; |
1288 | ||
873c642f | 1289 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
12883efb SRRH |
1290 | tracing_reset_online_cpus(&tr->trace_buffer); |
1291 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1292 | tracing_reset_online_cpus(&tr->max_buffer); | |
1293 | #endif | |
873c642f | 1294 | } |
9456f0fa SR |
1295 | } |
1296 | ||
bc0c38d1 | 1297 | #define SAVED_CMDLINES 128 |
2c7eea4c | 1298 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
1299 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
1300 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
1301 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
1302 | static int cmdline_idx; | |
edc35bd7 | 1303 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 1304 | |
25b0b44a | 1305 | /* temporary disable recording */ |
4fd27358 | 1306 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
1307 | |
1308 | static void trace_init_cmdlines(void) | |
1309 | { | |
2c7eea4c TG |
1310 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
1311 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
1312 | cmdline_idx = 0; |
1313 | } | |
1314 | ||
b5130b1e CE |
1315 | int is_tracing_stopped(void) |
1316 | { | |
2b6080f2 | 1317 | return global_trace.stop_count; |
b5130b1e CE |
1318 | } |
1319 | ||
0f048701 SR |
1320 | /** |
1321 | * tracing_start - quick start of the tracer | |
1322 | * | |
1323 | * If tracing is enabled but was stopped by tracing_stop, | |
1324 | * this will start the tracer back up. | |
1325 | */ | |
1326 | void tracing_start(void) | |
1327 | { | |
1328 | struct ring_buffer *buffer; | |
1329 | unsigned long flags; | |
1330 | ||
1331 | if (tracing_disabled) | |
1332 | return; | |
1333 | ||
2b6080f2 SR |
1334 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1335 | if (--global_trace.stop_count) { | |
1336 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1337 | /* Someone screwed up their debugging */ |
1338 | WARN_ON_ONCE(1); | |
2b6080f2 | 1339 | global_trace.stop_count = 0; |
b06a8301 | 1340 | } |
0f048701 SR |
1341 | goto out; |
1342 | } | |
1343 | ||
a2f80714 SR |
1344 | /* Prevent the buffers from switching */ |
1345 | arch_spin_lock(&ftrace_max_lock); | |
0f048701 | 1346 | |
12883efb | 1347 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1348 | if (buffer) |
1349 | ring_buffer_record_enable(buffer); | |
1350 | ||
12883efb SRRH |
1351 | #ifdef CONFIG_TRACER_MAX_TRACE |
1352 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1353 | if (buffer) |
1354 | ring_buffer_record_enable(buffer); | |
12883efb | 1355 | #endif |
0f048701 | 1356 | |
a2f80714 SR |
1357 | arch_spin_unlock(&ftrace_max_lock); |
1358 | ||
0f048701 SR |
1359 | ftrace_start(); |
1360 | out: | |
2b6080f2 SR |
1361 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1362 | } | |
1363 | ||
1364 | static void tracing_start_tr(struct trace_array *tr) | |
1365 | { | |
1366 | struct ring_buffer *buffer; | |
1367 | unsigned long flags; | |
1368 | ||
1369 | if (tracing_disabled) | |
1370 | return; | |
1371 | ||
1372 | /* If global, we need to also start the max tracer */ | |
1373 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1374 | return tracing_start(); | |
1375 | ||
1376 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1377 | ||
1378 | if (--tr->stop_count) { | |
1379 | if (tr->stop_count < 0) { | |
1380 | /* Someone screwed up their debugging */ | |
1381 | WARN_ON_ONCE(1); | |
1382 | tr->stop_count = 0; | |
1383 | } | |
1384 | goto out; | |
1385 | } | |
1386 | ||
12883efb | 1387 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1388 | if (buffer) |
1389 | ring_buffer_record_enable(buffer); | |
1390 | ||
1391 | out: | |
1392 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1393 | } |
1394 | ||
1395 | /** | |
1396 | * tracing_stop - quick stop of the tracer | |
1397 | * | |
1398 | * Light weight way to stop tracing. Use in conjunction with | |
1399 | * tracing_start. | |
1400 | */ | |
1401 | void tracing_stop(void) | |
1402 | { | |
1403 | struct ring_buffer *buffer; | |
1404 | unsigned long flags; | |
1405 | ||
1406 | ftrace_stop(); | |
2b6080f2 SR |
1407 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1408 | if (global_trace.stop_count++) | |
0f048701 SR |
1409 | goto out; |
1410 | ||
a2f80714 SR |
1411 | /* Prevent the buffers from switching */ |
1412 | arch_spin_lock(&ftrace_max_lock); | |
1413 | ||
12883efb | 1414 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1415 | if (buffer) |
1416 | ring_buffer_record_disable(buffer); | |
1417 | ||
12883efb SRRH |
1418 | #ifdef CONFIG_TRACER_MAX_TRACE |
1419 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1420 | if (buffer) |
1421 | ring_buffer_record_disable(buffer); | |
12883efb | 1422 | #endif |
0f048701 | 1423 | |
a2f80714 SR |
1424 | arch_spin_unlock(&ftrace_max_lock); |
1425 | ||
0f048701 | 1426 | out: |
2b6080f2 SR |
1427 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1428 | } | |
1429 | ||
1430 | static void tracing_stop_tr(struct trace_array *tr) | |
1431 | { | |
1432 | struct ring_buffer *buffer; | |
1433 | unsigned long flags; | |
1434 | ||
1435 | /* If global, we need to also stop the max tracer */ | |
1436 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1437 | return tracing_stop(); | |
1438 | ||
1439 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1440 | if (tr->stop_count++) | |
1441 | goto out; | |
1442 | ||
12883efb | 1443 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1444 | if (buffer) |
1445 | ring_buffer_record_disable(buffer); | |
1446 | ||
1447 | out: | |
1448 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1449 | } |
1450 | ||
e309b41d | 1451 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1452 | |
e309b41d | 1453 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1454 | { |
a635cf04 | 1455 | unsigned pid, idx; |
bc0c38d1 SR |
1456 | |
1457 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
1458 | return; | |
1459 | ||
1460 | /* | |
1461 | * It's not the end of the world if we don't get | |
1462 | * the lock, but we also don't want to spin | |
1463 | * nor do we want to disable interrupts, | |
1464 | * so if we miss here, then better luck next time. | |
1465 | */ | |
0199c4e6 | 1466 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
1467 | return; |
1468 | ||
1469 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1470 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1471 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1472 | ||
a635cf04 CE |
1473 | /* |
1474 | * Check whether the cmdline buffer at idx has a pid | |
1475 | * mapped. We are going to overwrite that entry so we | |
1476 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1477 | * would read the new comm for the old pid. | |
1478 | */ | |
1479 | pid = map_cmdline_to_pid[idx]; | |
1480 | if (pid != NO_CMDLINE_MAP) | |
1481 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1482 | |
a635cf04 | 1483 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1484 | map_pid_to_cmdline[tsk->pid] = idx; |
1485 | ||
1486 | cmdline_idx = idx; | |
1487 | } | |
1488 | ||
1489 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1490 | ||
0199c4e6 | 1491 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1492 | } |
1493 | ||
4ca53085 | 1494 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1495 | { |
bc0c38d1 SR |
1496 | unsigned map; |
1497 | ||
4ca53085 SR |
1498 | if (!pid) { |
1499 | strcpy(comm, "<idle>"); | |
1500 | return; | |
1501 | } | |
bc0c38d1 | 1502 | |
74bf4076 SR |
1503 | if (WARN_ON_ONCE(pid < 0)) { |
1504 | strcpy(comm, "<XXX>"); | |
1505 | return; | |
1506 | } | |
1507 | ||
4ca53085 SR |
1508 | if (pid > PID_MAX_DEFAULT) { |
1509 | strcpy(comm, "<...>"); | |
1510 | return; | |
1511 | } | |
bc0c38d1 | 1512 | |
5b6045a9 | 1513 | preempt_disable(); |
0199c4e6 | 1514 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1515 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1516 | if (map != NO_CMDLINE_MAP) |
1517 | strcpy(comm, saved_cmdlines[map]); | |
1518 | else | |
1519 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1520 | |
0199c4e6 | 1521 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1522 | preempt_enable(); |
bc0c38d1 SR |
1523 | } |
1524 | ||
e309b41d | 1525 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1526 | { |
0fb9656d | 1527 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1528 | return; |
1529 | ||
7ffbd48d SR |
1530 | if (!__this_cpu_read(trace_cmdline_save)) |
1531 | return; | |
1532 | ||
1533 | __this_cpu_write(trace_cmdline_save, false); | |
1534 | ||
bc0c38d1 SR |
1535 | trace_save_cmdline(tsk); |
1536 | } | |
1537 | ||
45dcd8b8 | 1538 | void |
38697053 SR |
1539 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1540 | int pc) | |
bc0c38d1 SR |
1541 | { |
1542 | struct task_struct *tsk = current; | |
bc0c38d1 | 1543 | |
777e208d SR |
1544 | entry->preempt_count = pc & 0xff; |
1545 | entry->pid = (tsk) ? tsk->pid : 0; | |
1546 | entry->flags = | |
9244489a | 1547 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1548 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1549 | #else |
1550 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1551 | #endif | |
bc0c38d1 SR |
1552 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1553 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
e5137b50 PZ |
1554 | (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) | |
1555 | (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0); | |
bc0c38d1 | 1556 | } |
f413cdb8 | 1557 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1558 | |
e77405ad SR |
1559 | struct ring_buffer_event * |
1560 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1561 | int type, | |
1562 | unsigned long len, | |
1563 | unsigned long flags, int pc) | |
51a763dd ACM |
1564 | { |
1565 | struct ring_buffer_event *event; | |
1566 | ||
e77405ad | 1567 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1568 | if (event != NULL) { |
1569 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1570 | ||
1571 | tracing_generic_entry_update(ent, flags, pc); | |
1572 | ent->type = type; | |
1573 | } | |
1574 | ||
1575 | return event; | |
1576 | } | |
51a763dd | 1577 | |
7ffbd48d SR |
1578 | void |
1579 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1580 | { | |
1581 | __this_cpu_write(trace_cmdline_save, true); | |
1582 | ring_buffer_unlock_commit(buffer, event); | |
1583 | } | |
1584 | ||
e77405ad SR |
1585 | static inline void |
1586 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1587 | struct ring_buffer_event *event, | |
0d5c6e1c | 1588 | unsigned long flags, int pc) |
51a763dd | 1589 | { |
7ffbd48d | 1590 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1591 | |
e77405ad SR |
1592 | ftrace_trace_stack(buffer, flags, 6, pc); |
1593 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1594 | } |
1595 | ||
e77405ad SR |
1596 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1597 | struct ring_buffer_event *event, | |
1598 | unsigned long flags, int pc) | |
07edf712 | 1599 | { |
0d5c6e1c | 1600 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
51a763dd | 1601 | } |
0d5c6e1c | 1602 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1603 | |
ccb469a1 SR |
1604 | struct ring_buffer_event * |
1605 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
1606 | struct ftrace_event_file *ftrace_file, | |
1607 | int type, unsigned long len, | |
1608 | unsigned long flags, int pc) | |
1609 | { | |
12883efb | 1610 | *current_rb = ftrace_file->tr->trace_buffer.buffer; |
ccb469a1 SR |
1611 | return trace_buffer_lock_reserve(*current_rb, |
1612 | type, len, flags, pc); | |
1613 | } | |
1614 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
1615 | ||
ef5580d0 | 1616 | struct ring_buffer_event * |
e77405ad SR |
1617 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1618 | int type, unsigned long len, | |
ef5580d0 SR |
1619 | unsigned long flags, int pc) |
1620 | { | |
12883efb | 1621 | *current_rb = global_trace.trace_buffer.buffer; |
e77405ad | 1622 | return trace_buffer_lock_reserve(*current_rb, |
ef5580d0 SR |
1623 | type, len, flags, pc); |
1624 | } | |
94487d6d | 1625 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1626 | |
e77405ad SR |
1627 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1628 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1629 | unsigned long flags, int pc) |
1630 | { | |
0d5c6e1c | 1631 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
07edf712 | 1632 | } |
94487d6d | 1633 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1634 | |
0d5c6e1c SR |
1635 | void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1636 | struct ring_buffer_event *event, | |
1637 | unsigned long flags, int pc, | |
1638 | struct pt_regs *regs) | |
1fd8df2c | 1639 | { |
7ffbd48d | 1640 | __buffer_unlock_commit(buffer, event); |
1fd8df2c MH |
1641 | |
1642 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1643 | ftrace_trace_userstack(buffer, flags, pc); | |
1644 | } | |
0d5c6e1c | 1645 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1646 | |
e77405ad SR |
1647 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1648 | struct ring_buffer_event *event) | |
77d9f465 | 1649 | { |
e77405ad | 1650 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1651 | } |
12acd473 | 1652 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1653 | |
e309b41d | 1654 | void |
7be42151 | 1655 | trace_function(struct trace_array *tr, |
38697053 SR |
1656 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1657 | int pc) | |
bc0c38d1 | 1658 | { |
e1112b4d | 1659 | struct ftrace_event_call *call = &event_function; |
12883efb | 1660 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 1661 | struct ring_buffer_event *event; |
777e208d | 1662 | struct ftrace_entry *entry; |
bc0c38d1 | 1663 | |
d769041f | 1664 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1665 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1666 | return; |
1667 | ||
e77405ad | 1668 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1669 | flags, pc); |
3928a8a2 SR |
1670 | if (!event) |
1671 | return; | |
1672 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1673 | entry->ip = ip; |
1674 | entry->parent_ip = parent_ip; | |
e1112b4d | 1675 | |
f306cc82 | 1676 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1677 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1678 | } |
1679 | ||
c0a0d0d3 | 1680 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1681 | |
1682 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1683 | struct ftrace_stack { | |
1684 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1685 | }; | |
1686 | ||
1687 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1688 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1689 | ||
e77405ad | 1690 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1691 | unsigned long flags, |
1fd8df2c | 1692 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1693 | { |
e1112b4d | 1694 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1695 | struct ring_buffer_event *event; |
777e208d | 1696 | struct stack_entry *entry; |
86387f7e | 1697 | struct stack_trace trace; |
4a9bd3f1 SR |
1698 | int use_stack; |
1699 | int size = FTRACE_STACK_ENTRIES; | |
1700 | ||
1701 | trace.nr_entries = 0; | |
1702 | trace.skip = skip; | |
1703 | ||
1704 | /* | |
1705 | * Since events can happen in NMIs there's no safe way to | |
1706 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1707 | * or NMI comes in, it will just have to use the default | |
1708 | * FTRACE_STACK_SIZE. | |
1709 | */ | |
1710 | preempt_disable_notrace(); | |
1711 | ||
82146529 | 1712 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
1713 | /* |
1714 | * We don't need any atomic variables, just a barrier. | |
1715 | * If an interrupt comes in, we don't care, because it would | |
1716 | * have exited and put the counter back to what we want. | |
1717 | * We just need a barrier to keep gcc from moving things | |
1718 | * around. | |
1719 | */ | |
1720 | barrier(); | |
1721 | if (use_stack == 1) { | |
1722 | trace.entries = &__get_cpu_var(ftrace_stack).calls[0]; | |
1723 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; | |
1724 | ||
1725 | if (regs) | |
1726 | save_stack_trace_regs(regs, &trace); | |
1727 | else | |
1728 | save_stack_trace(&trace); | |
1729 | ||
1730 | if (trace.nr_entries > size) | |
1731 | size = trace.nr_entries; | |
1732 | } else | |
1733 | /* From now on, use_stack is a boolean */ | |
1734 | use_stack = 0; | |
1735 | ||
1736 | size *= sizeof(unsigned long); | |
86387f7e | 1737 | |
e77405ad | 1738 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1739 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1740 | if (!event) |
4a9bd3f1 SR |
1741 | goto out; |
1742 | entry = ring_buffer_event_data(event); | |
86387f7e | 1743 | |
4a9bd3f1 SR |
1744 | memset(&entry->caller, 0, size); |
1745 | ||
1746 | if (use_stack) | |
1747 | memcpy(&entry->caller, trace.entries, | |
1748 | trace.nr_entries * sizeof(unsigned long)); | |
1749 | else { | |
1750 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1751 | trace.entries = entry->caller; | |
1752 | if (regs) | |
1753 | save_stack_trace_regs(regs, &trace); | |
1754 | else | |
1755 | save_stack_trace(&trace); | |
1756 | } | |
1757 | ||
1758 | entry->size = trace.nr_entries; | |
86387f7e | 1759 | |
f306cc82 | 1760 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1761 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1762 | |
1763 | out: | |
1764 | /* Again, don't let gcc optimize things here */ | |
1765 | barrier(); | |
82146529 | 1766 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
1767 | preempt_enable_notrace(); |
1768 | ||
f0a920d5 IM |
1769 | } |
1770 | ||
1fd8df2c MH |
1771 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1772 | int skip, int pc, struct pt_regs *regs) | |
1773 | { | |
1774 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1775 | return; | |
1776 | ||
1777 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1778 | } | |
1779 | ||
e77405ad SR |
1780 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1781 | int skip, int pc) | |
53614991 SR |
1782 | { |
1783 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1784 | return; | |
1785 | ||
1fd8df2c | 1786 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1787 | } |
1788 | ||
c0a0d0d3 FW |
1789 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1790 | int pc) | |
38697053 | 1791 | { |
12883efb | 1792 | __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); |
38697053 SR |
1793 | } |
1794 | ||
03889384 SR |
1795 | /** |
1796 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 1797 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 1798 | */ |
c142be8e | 1799 | void trace_dump_stack(int skip) |
03889384 SR |
1800 | { |
1801 | unsigned long flags; | |
1802 | ||
1803 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1804 | return; |
03889384 SR |
1805 | |
1806 | local_save_flags(flags); | |
1807 | ||
c142be8e SRRH |
1808 | /* |
1809 | * Skip 3 more, seems to get us at the caller of | |
1810 | * this function. | |
1811 | */ | |
1812 | skip += 3; | |
1813 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, | |
1814 | flags, skip, preempt_count(), NULL); | |
03889384 SR |
1815 | } |
1816 | ||
91e86e56 SR |
1817 | static DEFINE_PER_CPU(int, user_stack_count); |
1818 | ||
e77405ad SR |
1819 | void |
1820 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1821 | { |
e1112b4d | 1822 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1823 | struct ring_buffer_event *event; |
02b67518 TE |
1824 | struct userstack_entry *entry; |
1825 | struct stack_trace trace; | |
02b67518 TE |
1826 | |
1827 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1828 | return; | |
1829 | ||
b6345879 SR |
1830 | /* |
1831 | * NMIs can not handle page faults, even with fix ups. | |
1832 | * The save user stack can (and often does) fault. | |
1833 | */ | |
1834 | if (unlikely(in_nmi())) | |
1835 | return; | |
02b67518 | 1836 | |
91e86e56 SR |
1837 | /* |
1838 | * prevent recursion, since the user stack tracing may | |
1839 | * trigger other kernel events. | |
1840 | */ | |
1841 | preempt_disable(); | |
1842 | if (__this_cpu_read(user_stack_count)) | |
1843 | goto out; | |
1844 | ||
1845 | __this_cpu_inc(user_stack_count); | |
1846 | ||
e77405ad | 1847 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1848 | sizeof(*entry), flags, pc); |
02b67518 | 1849 | if (!event) |
1dbd1951 | 1850 | goto out_drop_count; |
02b67518 | 1851 | entry = ring_buffer_event_data(event); |
02b67518 | 1852 | |
48659d31 | 1853 | entry->tgid = current->tgid; |
02b67518 TE |
1854 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1855 | ||
1856 | trace.nr_entries = 0; | |
1857 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1858 | trace.skip = 0; | |
1859 | trace.entries = entry->caller; | |
1860 | ||
1861 | save_stack_trace_user(&trace); | |
f306cc82 | 1862 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1863 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1864 | |
1dbd1951 | 1865 | out_drop_count: |
91e86e56 | 1866 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1867 | out: |
1868 | preempt_enable(); | |
02b67518 TE |
1869 | } |
1870 | ||
4fd27358 HE |
1871 | #ifdef UNUSED |
1872 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1873 | { |
7be42151 | 1874 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1875 | } |
4fd27358 | 1876 | #endif /* UNUSED */ |
02b67518 | 1877 | |
c0a0d0d3 FW |
1878 | #endif /* CONFIG_STACKTRACE */ |
1879 | ||
07d777fe SR |
1880 | /* created for use with alloc_percpu */ |
1881 | struct trace_buffer_struct { | |
1882 | char buffer[TRACE_BUF_SIZE]; | |
1883 | }; | |
1884 | ||
1885 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1886 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1887 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1888 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1889 | ||
1890 | /* | |
1891 | * The buffer used is dependent on the context. There is a per cpu | |
1892 | * buffer for normal context, softirq contex, hard irq context and | |
1893 | * for NMI context. Thise allows for lockless recording. | |
1894 | * | |
1895 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1896 | */ | |
1897 | static char *get_trace_buf(void) | |
1898 | { | |
1899 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
1900 | |
1901 | /* | |
1902 | * If we have allocated per cpu buffers, then we do not | |
1903 | * need to do any locking. | |
1904 | */ | |
1905 | if (in_nmi()) | |
1906 | percpu_buffer = trace_percpu_nmi_buffer; | |
1907 | else if (in_irq()) | |
1908 | percpu_buffer = trace_percpu_irq_buffer; | |
1909 | else if (in_softirq()) | |
1910 | percpu_buffer = trace_percpu_sirq_buffer; | |
1911 | else | |
1912 | percpu_buffer = trace_percpu_buffer; | |
1913 | ||
1914 | if (!percpu_buffer) | |
1915 | return NULL; | |
1916 | ||
d8a0349c | 1917 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
1918 | } |
1919 | ||
1920 | static int alloc_percpu_trace_buffer(void) | |
1921 | { | |
1922 | struct trace_buffer_struct *buffers; | |
1923 | struct trace_buffer_struct *sirq_buffers; | |
1924 | struct trace_buffer_struct *irq_buffers; | |
1925 | struct trace_buffer_struct *nmi_buffers; | |
1926 | ||
1927 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1928 | if (!buffers) | |
1929 | goto err_warn; | |
1930 | ||
1931 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1932 | if (!sirq_buffers) | |
1933 | goto err_sirq; | |
1934 | ||
1935 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1936 | if (!irq_buffers) | |
1937 | goto err_irq; | |
1938 | ||
1939 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
1940 | if (!nmi_buffers) | |
1941 | goto err_nmi; | |
1942 | ||
1943 | trace_percpu_buffer = buffers; | |
1944 | trace_percpu_sirq_buffer = sirq_buffers; | |
1945 | trace_percpu_irq_buffer = irq_buffers; | |
1946 | trace_percpu_nmi_buffer = nmi_buffers; | |
1947 | ||
1948 | return 0; | |
1949 | ||
1950 | err_nmi: | |
1951 | free_percpu(irq_buffers); | |
1952 | err_irq: | |
1953 | free_percpu(sirq_buffers); | |
1954 | err_sirq: | |
1955 | free_percpu(buffers); | |
1956 | err_warn: | |
1957 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
1958 | return -ENOMEM; | |
1959 | } | |
1960 | ||
81698831 SR |
1961 | static int buffers_allocated; |
1962 | ||
07d777fe SR |
1963 | void trace_printk_init_buffers(void) |
1964 | { | |
07d777fe SR |
1965 | if (buffers_allocated) |
1966 | return; | |
1967 | ||
1968 | if (alloc_percpu_trace_buffer()) | |
1969 | return; | |
1970 | ||
1971 | pr_info("ftrace: Allocated trace_printk buffers\n"); | |
1972 | ||
b382ede6 SR |
1973 | /* Expand the buffers to set size */ |
1974 | tracing_update_buffers(); | |
1975 | ||
07d777fe | 1976 | buffers_allocated = 1; |
81698831 SR |
1977 | |
1978 | /* | |
1979 | * trace_printk_init_buffers() can be called by modules. | |
1980 | * If that happens, then we need to start cmdline recording | |
1981 | * directly here. If the global_trace.buffer is already | |
1982 | * allocated here, then this was called by module code. | |
1983 | */ | |
12883efb | 1984 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
1985 | tracing_start_cmdline_record(); |
1986 | } | |
1987 | ||
1988 | void trace_printk_start_comm(void) | |
1989 | { | |
1990 | /* Start tracing comms if trace printk is set */ | |
1991 | if (!buffers_allocated) | |
1992 | return; | |
1993 | tracing_start_cmdline_record(); | |
1994 | } | |
1995 | ||
1996 | static void trace_printk_start_stop_comm(int enabled) | |
1997 | { | |
1998 | if (!buffers_allocated) | |
1999 | return; | |
2000 | ||
2001 | if (enabled) | |
2002 | tracing_start_cmdline_record(); | |
2003 | else | |
2004 | tracing_stop_cmdline_record(); | |
07d777fe SR |
2005 | } |
2006 | ||
769b0441 | 2007 | /** |
48ead020 | 2008 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
2009 | * |
2010 | */ | |
40ce74f1 | 2011 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 2012 | { |
e1112b4d | 2013 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 2014 | struct ring_buffer_event *event; |
e77405ad | 2015 | struct ring_buffer *buffer; |
769b0441 | 2016 | struct trace_array *tr = &global_trace; |
48ead020 | 2017 | struct bprint_entry *entry; |
769b0441 | 2018 | unsigned long flags; |
07d777fe SR |
2019 | char *tbuffer; |
2020 | int len = 0, size, pc; | |
769b0441 FW |
2021 | |
2022 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
2023 | return 0; | |
2024 | ||
2025 | /* Don't pollute graph traces with trace_vprintk internals */ | |
2026 | pause_graph_tracing(); | |
2027 | ||
2028 | pc = preempt_count(); | |
5168ae50 | 2029 | preempt_disable_notrace(); |
769b0441 | 2030 | |
07d777fe SR |
2031 | tbuffer = get_trace_buf(); |
2032 | if (!tbuffer) { | |
2033 | len = 0; | |
769b0441 | 2034 | goto out; |
07d777fe | 2035 | } |
769b0441 | 2036 | |
07d777fe | 2037 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 2038 | |
07d777fe SR |
2039 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
2040 | goto out; | |
769b0441 | 2041 | |
07d777fe | 2042 | local_save_flags(flags); |
769b0441 | 2043 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 2044 | buffer = tr->trace_buffer.buffer; |
e77405ad SR |
2045 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
2046 | flags, pc); | |
769b0441 | 2047 | if (!event) |
07d777fe | 2048 | goto out; |
769b0441 FW |
2049 | entry = ring_buffer_event_data(event); |
2050 | entry->ip = ip; | |
769b0441 FW |
2051 | entry->fmt = fmt; |
2052 | ||
07d777fe | 2053 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
f306cc82 | 2054 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2055 | __buffer_unlock_commit(buffer, event); |
d931369b SR |
2056 | ftrace_trace_stack(buffer, flags, 6, pc); |
2057 | } | |
769b0441 | 2058 | |
769b0441 | 2059 | out: |
5168ae50 | 2060 | preempt_enable_notrace(); |
769b0441 FW |
2061 | unpause_graph_tracing(); |
2062 | ||
2063 | return len; | |
2064 | } | |
48ead020 FW |
2065 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
2066 | ||
12883efb SRRH |
2067 | static int |
2068 | __trace_array_vprintk(struct ring_buffer *buffer, | |
2069 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 2070 | { |
e1112b4d | 2071 | struct ftrace_event_call *call = &event_print; |
48ead020 | 2072 | struct ring_buffer_event *event; |
07d777fe | 2073 | int len = 0, size, pc; |
48ead020 | 2074 | struct print_entry *entry; |
07d777fe SR |
2075 | unsigned long flags; |
2076 | char *tbuffer; | |
48ead020 FW |
2077 | |
2078 | if (tracing_disabled || tracing_selftest_running) | |
2079 | return 0; | |
2080 | ||
07d777fe SR |
2081 | /* Don't pollute graph traces with trace_vprintk internals */ |
2082 | pause_graph_tracing(); | |
2083 | ||
48ead020 FW |
2084 | pc = preempt_count(); |
2085 | preempt_disable_notrace(); | |
48ead020 | 2086 | |
07d777fe SR |
2087 | |
2088 | tbuffer = get_trace_buf(); | |
2089 | if (!tbuffer) { | |
2090 | len = 0; | |
48ead020 | 2091 | goto out; |
07d777fe | 2092 | } |
48ead020 | 2093 | |
07d777fe SR |
2094 | len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
2095 | if (len > TRACE_BUF_SIZE) | |
2096 | goto out; | |
48ead020 | 2097 | |
07d777fe | 2098 | local_save_flags(flags); |
48ead020 | 2099 | size = sizeof(*entry) + len + 1; |
e77405ad | 2100 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
07d777fe | 2101 | flags, pc); |
48ead020 | 2102 | if (!event) |
07d777fe | 2103 | goto out; |
48ead020 | 2104 | entry = ring_buffer_event_data(event); |
c13d2f7c | 2105 | entry->ip = ip; |
48ead020 | 2106 | |
07d777fe | 2107 | memcpy(&entry->buf, tbuffer, len); |
c13d2f7c | 2108 | entry->buf[len] = '\0'; |
f306cc82 | 2109 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2110 | __buffer_unlock_commit(buffer, event); |
07d777fe | 2111 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 2112 | } |
48ead020 FW |
2113 | out: |
2114 | preempt_enable_notrace(); | |
07d777fe | 2115 | unpause_graph_tracing(); |
48ead020 FW |
2116 | |
2117 | return len; | |
2118 | } | |
659372d3 | 2119 | |
12883efb SRRH |
2120 | int trace_array_vprintk(struct trace_array *tr, |
2121 | unsigned long ip, const char *fmt, va_list args) | |
2122 | { | |
2123 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
2124 | } | |
2125 | ||
2126 | int trace_array_printk(struct trace_array *tr, | |
2127 | unsigned long ip, const char *fmt, ...) | |
2128 | { | |
2129 | int ret; | |
2130 | va_list ap; | |
2131 | ||
2132 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2133 | return 0; | |
2134 | ||
2135 | va_start(ap, fmt); | |
2136 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
2137 | va_end(ap); | |
2138 | return ret; | |
2139 | } | |
2140 | ||
2141 | int trace_array_printk_buf(struct ring_buffer *buffer, | |
2142 | unsigned long ip, const char *fmt, ...) | |
2143 | { | |
2144 | int ret; | |
2145 | va_list ap; | |
2146 | ||
2147 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2148 | return 0; | |
2149 | ||
2150 | va_start(ap, fmt); | |
2151 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
2152 | va_end(ap); | |
2153 | return ret; | |
2154 | } | |
2155 | ||
659372d3 SR |
2156 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
2157 | { | |
a813a159 | 2158 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 2159 | } |
769b0441 FW |
2160 | EXPORT_SYMBOL_GPL(trace_vprintk); |
2161 | ||
e2ac8ef5 | 2162 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 2163 | { |
6d158a81 SR |
2164 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
2165 | ||
5a90f577 | 2166 | iter->idx++; |
6d158a81 SR |
2167 | if (buf_iter) |
2168 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
2169 | } |
2170 | ||
e309b41d | 2171 | static struct trace_entry * |
bc21b478 SR |
2172 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
2173 | unsigned long *lost_events) | |
dd0e545f | 2174 | { |
3928a8a2 | 2175 | struct ring_buffer_event *event; |
6d158a81 | 2176 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 2177 | |
d769041f SR |
2178 | if (buf_iter) |
2179 | event = ring_buffer_iter_peek(buf_iter, ts); | |
2180 | else | |
12883efb | 2181 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 2182 | lost_events); |
d769041f | 2183 | |
4a9bd3f1 SR |
2184 | if (event) { |
2185 | iter->ent_size = ring_buffer_event_length(event); | |
2186 | return ring_buffer_event_data(event); | |
2187 | } | |
2188 | iter->ent_size = 0; | |
2189 | return NULL; | |
dd0e545f | 2190 | } |
d769041f | 2191 | |
dd0e545f | 2192 | static struct trace_entry * |
bc21b478 SR |
2193 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
2194 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 2195 | { |
12883efb | 2196 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 2197 | struct trace_entry *ent, *next = NULL; |
aa27497c | 2198 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 2199 | int cpu_file = iter->cpu_file; |
3928a8a2 | 2200 | u64 next_ts = 0, ts; |
bc0c38d1 | 2201 | int next_cpu = -1; |
12b5da34 | 2202 | int next_size = 0; |
bc0c38d1 SR |
2203 | int cpu; |
2204 | ||
b04cc6b1 FW |
2205 | /* |
2206 | * If we are in a per_cpu trace file, don't bother by iterating over | |
2207 | * all cpu and peek directly. | |
2208 | */ | |
ae3b5093 | 2209 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
2210 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
2211 | return NULL; | |
bc21b478 | 2212 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
2213 | if (ent_cpu) |
2214 | *ent_cpu = cpu_file; | |
2215 | ||
2216 | return ent; | |
2217 | } | |
2218 | ||
ab46428c | 2219 | for_each_tracing_cpu(cpu) { |
dd0e545f | 2220 | |
3928a8a2 SR |
2221 | if (ring_buffer_empty_cpu(buffer, cpu)) |
2222 | continue; | |
dd0e545f | 2223 | |
bc21b478 | 2224 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 2225 | |
cdd31cd2 IM |
2226 | /* |
2227 | * Pick the entry with the smallest timestamp: | |
2228 | */ | |
3928a8a2 | 2229 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
2230 | next = ent; |
2231 | next_cpu = cpu; | |
3928a8a2 | 2232 | next_ts = ts; |
bc21b478 | 2233 | next_lost = lost_events; |
12b5da34 | 2234 | next_size = iter->ent_size; |
bc0c38d1 SR |
2235 | } |
2236 | } | |
2237 | ||
12b5da34 SR |
2238 | iter->ent_size = next_size; |
2239 | ||
bc0c38d1 SR |
2240 | if (ent_cpu) |
2241 | *ent_cpu = next_cpu; | |
2242 | ||
3928a8a2 SR |
2243 | if (ent_ts) |
2244 | *ent_ts = next_ts; | |
2245 | ||
bc21b478 SR |
2246 | if (missing_events) |
2247 | *missing_events = next_lost; | |
2248 | ||
bc0c38d1 SR |
2249 | return next; |
2250 | } | |
2251 | ||
dd0e545f | 2252 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
2253 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
2254 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 2255 | { |
bc21b478 | 2256 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
2257 | } |
2258 | ||
2259 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 2260 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 2261 | { |
bc21b478 SR |
2262 | iter->ent = __find_next_entry(iter, &iter->cpu, |
2263 | &iter->lost_events, &iter->ts); | |
dd0e545f | 2264 | |
3928a8a2 | 2265 | if (iter->ent) |
e2ac8ef5 | 2266 | trace_iterator_increment(iter); |
dd0e545f | 2267 | |
3928a8a2 | 2268 | return iter->ent ? iter : NULL; |
b3806b43 | 2269 | } |
bc0c38d1 | 2270 | |
e309b41d | 2271 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 2272 | { |
12883efb | 2273 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 2274 | &iter->lost_events); |
bc0c38d1 SR |
2275 | } |
2276 | ||
e309b41d | 2277 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
2278 | { |
2279 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 2280 | int i = (int)*pos; |
4e3c3333 | 2281 | void *ent; |
bc0c38d1 | 2282 | |
a63ce5b3 SR |
2283 | WARN_ON_ONCE(iter->leftover); |
2284 | ||
bc0c38d1 SR |
2285 | (*pos)++; |
2286 | ||
2287 | /* can't go backwards */ | |
2288 | if (iter->idx > i) | |
2289 | return NULL; | |
2290 | ||
2291 | if (iter->idx < 0) | |
955b61e5 | 2292 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2293 | else |
2294 | ent = iter; | |
2295 | ||
2296 | while (ent && iter->idx < i) | |
955b61e5 | 2297 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2298 | |
2299 | iter->pos = *pos; | |
2300 | ||
bc0c38d1 SR |
2301 | return ent; |
2302 | } | |
2303 | ||
955b61e5 | 2304 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 2305 | { |
2f26ebd5 SR |
2306 | struct ring_buffer_event *event; |
2307 | struct ring_buffer_iter *buf_iter; | |
2308 | unsigned long entries = 0; | |
2309 | u64 ts; | |
2310 | ||
12883efb | 2311 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 2312 | |
6d158a81 SR |
2313 | buf_iter = trace_buffer_iter(iter, cpu); |
2314 | if (!buf_iter) | |
2f26ebd5 SR |
2315 | return; |
2316 | ||
2f26ebd5 SR |
2317 | ring_buffer_iter_reset(buf_iter); |
2318 | ||
2319 | /* | |
2320 | * We could have the case with the max latency tracers | |
2321 | * that a reset never took place on a cpu. This is evident | |
2322 | * by the timestamp being before the start of the buffer. | |
2323 | */ | |
2324 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 2325 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
2326 | break; |
2327 | entries++; | |
2328 | ring_buffer_read(buf_iter, NULL); | |
2329 | } | |
2330 | ||
12883efb | 2331 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2332 | } |
2333 | ||
d7350c3f | 2334 | /* |
d7350c3f FW |
2335 | * The current tracer is copied to avoid a global locking |
2336 | * all around. | |
2337 | */ | |
bc0c38d1 SR |
2338 | static void *s_start(struct seq_file *m, loff_t *pos) |
2339 | { | |
2340 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2341 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2342 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2343 | void *p = NULL; |
2344 | loff_t l = 0; | |
3928a8a2 | 2345 | int cpu; |
bc0c38d1 | 2346 | |
2fd196ec HT |
2347 | /* |
2348 | * copy the tracer to avoid using a global lock all around. | |
2349 | * iter->trace is a copy of current_trace, the pointer to the | |
2350 | * name may be used instead of a strcmp(), as iter->trace->name | |
2351 | * will point to the same string as current_trace->name. | |
2352 | */ | |
bc0c38d1 | 2353 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2354 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2355 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2356 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2357 | |
12883efb | 2358 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2359 | if (iter->snapshot && iter->trace->use_max_tr) |
2360 | return ERR_PTR(-EBUSY); | |
12883efb | 2361 | #endif |
debdd57f HT |
2362 | |
2363 | if (!iter->snapshot) | |
2364 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2365 | |
bc0c38d1 SR |
2366 | if (*pos != iter->pos) { |
2367 | iter->ent = NULL; | |
2368 | iter->cpu = 0; | |
2369 | iter->idx = -1; | |
2370 | ||
ae3b5093 | 2371 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2372 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2373 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2374 | } else |
2f26ebd5 | 2375 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2376 | |
ac91d854 | 2377 | iter->leftover = 0; |
bc0c38d1 SR |
2378 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2379 | ; | |
2380 | ||
2381 | } else { | |
a63ce5b3 SR |
2382 | /* |
2383 | * If we overflowed the seq_file before, then we want | |
2384 | * to just reuse the trace_seq buffer again. | |
2385 | */ | |
2386 | if (iter->leftover) | |
2387 | p = iter; | |
2388 | else { | |
2389 | l = *pos - 1; | |
2390 | p = s_next(m, p, &l); | |
2391 | } | |
bc0c38d1 SR |
2392 | } |
2393 | ||
4f535968 | 2394 | trace_event_read_lock(); |
7e53bd42 | 2395 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2396 | return p; |
2397 | } | |
2398 | ||
2399 | static void s_stop(struct seq_file *m, void *p) | |
2400 | { | |
7e53bd42 LJ |
2401 | struct trace_iterator *iter = m->private; |
2402 | ||
12883efb | 2403 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2404 | if (iter->snapshot && iter->trace->use_max_tr) |
2405 | return; | |
12883efb | 2406 | #endif |
debdd57f HT |
2407 | |
2408 | if (!iter->snapshot) | |
2409 | atomic_dec(&trace_record_cmdline_disabled); | |
12883efb | 2410 | |
7e53bd42 | 2411 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2412 | trace_event_read_unlock(); |
bc0c38d1 SR |
2413 | } |
2414 | ||
39eaf7ef | 2415 | static void |
12883efb SRRH |
2416 | get_total_entries(struct trace_buffer *buf, |
2417 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
2418 | { |
2419 | unsigned long count; | |
2420 | int cpu; | |
2421 | ||
2422 | *total = 0; | |
2423 | *entries = 0; | |
2424 | ||
2425 | for_each_tracing_cpu(cpu) { | |
12883efb | 2426 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2427 | /* |
2428 | * If this buffer has skipped entries, then we hold all | |
2429 | * entries for the trace and we need to ignore the | |
2430 | * ones before the time stamp. | |
2431 | */ | |
12883efb SRRH |
2432 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
2433 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2434 | /* total is the same as the entries */ |
2435 | *total += count; | |
2436 | } else | |
2437 | *total += count + | |
12883efb | 2438 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2439 | *entries += count; |
2440 | } | |
2441 | } | |
2442 | ||
e309b41d | 2443 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2444 | { |
a6168353 ME |
2445 | seq_puts(m, "# _------=> CPU# \n"); |
2446 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
2447 | seq_puts(m, "# | / _----=> need-resched \n"); | |
2448 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
2449 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
2450 | seq_puts(m, "# |||| / delay \n"); |
2451 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
2452 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2453 | } |
2454 | ||
12883efb | 2455 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 2456 | { |
39eaf7ef SR |
2457 | unsigned long total; |
2458 | unsigned long entries; | |
2459 | ||
12883efb | 2460 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
2461 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
2462 | entries, total, num_online_cpus()); | |
2463 | seq_puts(m, "#\n"); | |
2464 | } | |
2465 | ||
12883efb | 2466 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) |
39eaf7ef | 2467 | { |
12883efb | 2468 | print_event_info(buf, m); |
77271ce4 | 2469 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
a6168353 | 2470 | seq_puts(m, "# | | | | |\n"); |
bc0c38d1 SR |
2471 | } |
2472 | ||
12883efb | 2473 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) |
77271ce4 | 2474 | { |
12883efb | 2475 | print_event_info(buf, m); |
77271ce4 SR |
2476 | seq_puts(m, "# _-----=> irqs-off\n"); |
2477 | seq_puts(m, "# / _----=> need-resched\n"); | |
2478 | seq_puts(m, "# | / _---=> hardirq/softirq\n"); | |
2479 | seq_puts(m, "# || / _--=> preempt-depth\n"); | |
2480 | seq_puts(m, "# ||| / delay\n"); | |
2481 | seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); | |
2482 | seq_puts(m, "# | | | |||| | |\n"); | |
2483 | } | |
bc0c38d1 | 2484 | |
62b915f1 | 2485 | void |
bc0c38d1 SR |
2486 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2487 | { | |
2488 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
12883efb SRRH |
2489 | struct trace_buffer *buf = iter->trace_buffer; |
2490 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 2491 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2492 | unsigned long entries; |
2493 | unsigned long total; | |
bc0c38d1 SR |
2494 | const char *name = "preemption"; |
2495 | ||
d840f718 | 2496 | name = type->name; |
bc0c38d1 | 2497 | |
12883efb | 2498 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 2499 | |
888b55dc | 2500 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2501 | name, UTS_RELEASE); |
888b55dc | 2502 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2503 | "---------------------------------\n"); |
888b55dc | 2504 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2505 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2506 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2507 | entries, |
4c11d7ae | 2508 | total, |
12883efb | 2509 | buf->cpu, |
bc0c38d1 SR |
2510 | #if defined(CONFIG_PREEMPT_NONE) |
2511 | "server", | |
2512 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2513 | "desktop", | |
b5c21b45 | 2514 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2515 | "preempt", |
2516 | #else | |
2517 | "unknown", | |
2518 | #endif | |
2519 | /* These are reserved for later use */ | |
2520 | 0, 0, 0, 0); | |
2521 | #ifdef CONFIG_SMP | |
2522 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2523 | #else | |
2524 | seq_puts(m, ")\n"); | |
2525 | #endif | |
888b55dc KM |
2526 | seq_puts(m, "# -----------------\n"); |
2527 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2528 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2529 | data->comm, data->pid, |
2530 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2531 | data->policy, data->rt_priority); |
888b55dc | 2532 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2533 | |
2534 | if (data->critical_start) { | |
888b55dc | 2535 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2536 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2537 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2538 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2539 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2540 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2541 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2542 | } |
2543 | ||
888b55dc | 2544 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2545 | } |
2546 | ||
a309720c SR |
2547 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2548 | { | |
2549 | struct trace_seq *s = &iter->seq; | |
2550 | ||
12ef7d44 SR |
2551 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2552 | return; | |
2553 | ||
2554 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2555 | return; | |
2556 | ||
4462344e | 2557 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2558 | return; |
2559 | ||
12883efb | 2560 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
2561 | return; |
2562 | ||
4462344e | 2563 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2564 | |
2565 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2566 | if (iter->idx > 1) | |
2567 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2568 | iter->cpu); | |
a309720c SR |
2569 | } |
2570 | ||
2c4f035f | 2571 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2572 | { |
214023c3 | 2573 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2574 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2575 | struct trace_entry *entry; |
f633cef0 | 2576 | struct trace_event *event; |
bc0c38d1 | 2577 | |
4e3c3333 | 2578 | entry = iter->ent; |
dd0e545f | 2579 | |
a309720c SR |
2580 | test_cpu_buff_start(iter); |
2581 | ||
c4a8e8be | 2582 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2583 | |
c4a8e8be | 2584 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
2585 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2586 | if (!trace_print_lat_context(iter)) | |
2587 | goto partial; | |
2588 | } else { | |
2589 | if (!trace_print_context(iter)) | |
2590 | goto partial; | |
2591 | } | |
c4a8e8be | 2592 | } |
bc0c38d1 | 2593 | |
268ccda0 | 2594 | if (event) |
a9a57763 | 2595 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
2596 | |
2597 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
2598 | goto partial; | |
02b67518 | 2599 | |
2c4f035f | 2600 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2601 | partial: |
2602 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
2603 | } |
2604 | ||
2c4f035f | 2605 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2606 | { |
2607 | struct trace_seq *s = &iter->seq; | |
2608 | struct trace_entry *entry; | |
f633cef0 | 2609 | struct trace_event *event; |
f9896bf3 IM |
2610 | |
2611 | entry = iter->ent; | |
dd0e545f | 2612 | |
c4a8e8be | 2613 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
2614 | if (!trace_seq_printf(s, "%d %d %llu ", |
2615 | entry->pid, iter->cpu, iter->ts)) | |
2616 | goto partial; | |
c4a8e8be | 2617 | } |
f9896bf3 | 2618 | |
f633cef0 | 2619 | event = ftrace_find_event(entry->type); |
268ccda0 | 2620 | if (event) |
a9a57763 | 2621 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
2622 | |
2623 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
2624 | goto partial; | |
777e208d | 2625 | |
2c4f035f | 2626 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2627 | partial: |
2628 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
2629 | } |
2630 | ||
2c4f035f | 2631 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2632 | { |
2633 | struct trace_seq *s = &iter->seq; | |
2634 | unsigned char newline = '\n'; | |
2635 | struct trace_entry *entry; | |
f633cef0 | 2636 | struct trace_event *event; |
5e3ca0ec IM |
2637 | |
2638 | entry = iter->ent; | |
dd0e545f | 2639 | |
c4a8e8be FW |
2640 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2641 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
2642 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
2643 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
2644 | } | |
5e3ca0ec | 2645 | |
f633cef0 | 2646 | event = ftrace_find_event(entry->type); |
268ccda0 | 2647 | if (event) { |
a9a57763 | 2648 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2649 | if (ret != TRACE_TYPE_HANDLED) |
2650 | return ret; | |
2651 | } | |
7104f300 | 2652 | |
5e3ca0ec IM |
2653 | SEQ_PUT_FIELD_RET(s, newline); |
2654 | ||
2c4f035f | 2655 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
2656 | } |
2657 | ||
2c4f035f | 2658 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2659 | { |
2660 | struct trace_seq *s = &iter->seq; | |
2661 | struct trace_entry *entry; | |
f633cef0 | 2662 | struct trace_event *event; |
cb0f12aa IM |
2663 | |
2664 | entry = iter->ent; | |
dd0e545f | 2665 | |
c4a8e8be FW |
2666 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2667 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 2668 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2669 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2670 | } | |
cb0f12aa | 2671 | |
f633cef0 | 2672 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2673 | return event ? event->funcs->binary(iter, 0, event) : |
2674 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2675 | } |
2676 | ||
62b915f1 | 2677 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2678 | { |
6d158a81 | 2679 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2680 | int cpu; |
2681 | ||
9aba60fe | 2682 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 2683 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 2684 | cpu = iter->cpu_file; |
6d158a81 SR |
2685 | buf_iter = trace_buffer_iter(iter, cpu); |
2686 | if (buf_iter) { | |
2687 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2688 | return 0; |
2689 | } else { | |
12883efb | 2690 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
2691 | return 0; |
2692 | } | |
2693 | return 1; | |
2694 | } | |
2695 | ||
ab46428c | 2696 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2697 | buf_iter = trace_buffer_iter(iter, cpu); |
2698 | if (buf_iter) { | |
2699 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2700 | return 0; |
2701 | } else { | |
12883efb | 2702 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
2703 | return 0; |
2704 | } | |
bc0c38d1 | 2705 | } |
d769041f | 2706 | |
797d3712 | 2707 | return 1; |
bc0c38d1 SR |
2708 | } |
2709 | ||
4f535968 | 2710 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2711 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2712 | { |
2c4f035f FW |
2713 | enum print_line_t ret; |
2714 | ||
ee5e51f5 JO |
2715 | if (iter->lost_events && |
2716 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2717 | iter->cpu, iter->lost_events)) | |
2718 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2719 | |
2c4f035f FW |
2720 | if (iter->trace && iter->trace->print_line) { |
2721 | ret = iter->trace->print_line(iter); | |
2722 | if (ret != TRACE_TYPE_UNHANDLED) | |
2723 | return ret; | |
2724 | } | |
72829bc3 | 2725 | |
09ae7234 SRRH |
2726 | if (iter->ent->type == TRACE_BPUTS && |
2727 | trace_flags & TRACE_ITER_PRINTK && | |
2728 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
2729 | return trace_print_bputs_msg_only(iter); | |
2730 | ||
48ead020 FW |
2731 | if (iter->ent->type == TRACE_BPRINT && |
2732 | trace_flags & TRACE_ITER_PRINTK && | |
2733 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2734 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2735 | |
66896a85 FW |
2736 | if (iter->ent->type == TRACE_PRINT && |
2737 | trace_flags & TRACE_ITER_PRINTK && | |
2738 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2739 | return trace_print_printk_msg_only(iter); |
66896a85 | 2740 | |
cb0f12aa IM |
2741 | if (trace_flags & TRACE_ITER_BIN) |
2742 | return print_bin_fmt(iter); | |
2743 | ||
5e3ca0ec IM |
2744 | if (trace_flags & TRACE_ITER_HEX) |
2745 | return print_hex_fmt(iter); | |
2746 | ||
f9896bf3 IM |
2747 | if (trace_flags & TRACE_ITER_RAW) |
2748 | return print_raw_fmt(iter); | |
2749 | ||
f9896bf3 IM |
2750 | return print_trace_fmt(iter); |
2751 | } | |
2752 | ||
7e9a49ef JO |
2753 | void trace_latency_header(struct seq_file *m) |
2754 | { | |
2755 | struct trace_iterator *iter = m->private; | |
2756 | ||
2757 | /* print nothing if the buffers are empty */ | |
2758 | if (trace_empty(iter)) | |
2759 | return; | |
2760 | ||
2761 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2762 | print_trace_header(m, iter); | |
2763 | ||
2764 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2765 | print_lat_help_header(m); | |
2766 | } | |
2767 | ||
62b915f1 JO |
2768 | void trace_default_header(struct seq_file *m) |
2769 | { | |
2770 | struct trace_iterator *iter = m->private; | |
2771 | ||
f56e7f8e JO |
2772 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2773 | return; | |
2774 | ||
62b915f1 JO |
2775 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2776 | /* print nothing if the buffers are empty */ | |
2777 | if (trace_empty(iter)) | |
2778 | return; | |
2779 | print_trace_header(m, iter); | |
2780 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2781 | print_lat_help_header(m); | |
2782 | } else { | |
77271ce4 SR |
2783 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2784 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
12883efb | 2785 | print_func_help_header_irq(iter->trace_buffer, m); |
77271ce4 | 2786 | else |
12883efb | 2787 | print_func_help_header(iter->trace_buffer, m); |
77271ce4 | 2788 | } |
62b915f1 JO |
2789 | } |
2790 | } | |
2791 | ||
e0a413f6 SR |
2792 | static void test_ftrace_alive(struct seq_file *m) |
2793 | { | |
2794 | if (!ftrace_is_dead()) | |
2795 | return; | |
2796 | seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
2797 | seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n"); | |
2798 | } | |
2799 | ||
d8741e2e | 2800 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 2801 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 2802 | { |
d8741e2e SRRH |
2803 | seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n"); |
2804 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2805 | seq_printf(m, "# Takes a snapshot of the main buffer.\n"); | |
b9be6d02 | 2806 | seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n"); |
d8741e2e SRRH |
2807 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); |
2808 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2809 | } | |
f1affcaa SRRH |
2810 | |
2811 | static void show_snapshot_percpu_help(struct seq_file *m) | |
2812 | { | |
2813 | seq_printf(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); | |
2814 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP | |
2815 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2816 | seq_printf(m, "# Takes a snapshot of the main buffer for this cpu.\n"); | |
2817 | #else | |
2818 | seq_printf(m, "# echo 1 > snapshot : Not supported with this kernel.\n"); | |
2819 | seq_printf(m, "# Must use main snapshot file to allocate.\n"); | |
2820 | #endif | |
2821 | seq_printf(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n"); | |
2822 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); | |
2823 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2824 | } | |
2825 | ||
d8741e2e SRRH |
2826 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
2827 | { | |
45ad21ca | 2828 | if (iter->tr->allocated_snapshot) |
d8741e2e SRRH |
2829 | seq_printf(m, "#\n# * Snapshot is allocated *\n#\n"); |
2830 | else | |
2831 | seq_printf(m, "#\n# * Snapshot is freed *\n#\n"); | |
2832 | ||
2833 | seq_printf(m, "# Snapshot commands:\n"); | |
f1affcaa SRRH |
2834 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
2835 | show_snapshot_main_help(m); | |
2836 | else | |
2837 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
2838 | } |
2839 | #else | |
2840 | /* Should never be called */ | |
2841 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
2842 | #endif | |
2843 | ||
bc0c38d1 SR |
2844 | static int s_show(struct seq_file *m, void *v) |
2845 | { | |
2846 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2847 | int ret; |
bc0c38d1 SR |
2848 | |
2849 | if (iter->ent == NULL) { | |
2850 | if (iter->tr) { | |
2851 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2852 | seq_puts(m, "#\n"); | |
e0a413f6 | 2853 | test_ftrace_alive(m); |
bc0c38d1 | 2854 | } |
d8741e2e SRRH |
2855 | if (iter->snapshot && trace_empty(iter)) |
2856 | print_snapshot_help(m, iter); | |
2857 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 2858 | iter->trace->print_header(m); |
62b915f1 JO |
2859 | else |
2860 | trace_default_header(m); | |
2861 | ||
a63ce5b3 SR |
2862 | } else if (iter->leftover) { |
2863 | /* | |
2864 | * If we filled the seq_file buffer earlier, we | |
2865 | * want to just show it now. | |
2866 | */ | |
2867 | ret = trace_print_seq(m, &iter->seq); | |
2868 | ||
2869 | /* ret should this time be zero, but you never know */ | |
2870 | iter->leftover = ret; | |
2871 | ||
bc0c38d1 | 2872 | } else { |
f9896bf3 | 2873 | print_trace_line(iter); |
a63ce5b3 SR |
2874 | ret = trace_print_seq(m, &iter->seq); |
2875 | /* | |
2876 | * If we overflow the seq_file buffer, then it will | |
2877 | * ask us for this data again at start up. | |
2878 | * Use that instead. | |
2879 | * ret is 0 if seq_file write succeeded. | |
2880 | * -1 otherwise. | |
2881 | */ | |
2882 | iter->leftover = ret; | |
bc0c38d1 SR |
2883 | } |
2884 | ||
2885 | return 0; | |
2886 | } | |
2887 | ||
649e9c70 ON |
2888 | /* |
2889 | * Should be used after trace_array_get(), trace_types_lock | |
2890 | * ensures that i_cdev was already initialized. | |
2891 | */ | |
2892 | static inline int tracing_get_cpu(struct inode *inode) | |
2893 | { | |
2894 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
2895 | return (long)inode->i_cdev - 1; | |
2896 | return RING_BUFFER_ALL_CPUS; | |
2897 | } | |
2898 | ||
88e9d34c | 2899 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2900 | .start = s_start, |
2901 | .next = s_next, | |
2902 | .stop = s_stop, | |
2903 | .show = s_show, | |
bc0c38d1 SR |
2904 | }; |
2905 | ||
e309b41d | 2906 | static struct trace_iterator * |
6484c71c | 2907 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 2908 | { |
6484c71c | 2909 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 2910 | struct trace_iterator *iter; |
50e18b94 | 2911 | int cpu; |
bc0c38d1 | 2912 | |
85a2f9b4 SR |
2913 | if (tracing_disabled) |
2914 | return ERR_PTR(-ENODEV); | |
60a11774 | 2915 | |
50e18b94 | 2916 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2917 | if (!iter) |
2918 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2919 | |
6d158a81 SR |
2920 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
2921 | GFP_KERNEL); | |
93574fcc DC |
2922 | if (!iter->buffer_iter) |
2923 | goto release; | |
2924 | ||
d7350c3f FW |
2925 | /* |
2926 | * We make a copy of the current tracer to avoid concurrent | |
2927 | * changes on it while we are reading. | |
2928 | */ | |
bc0c38d1 | 2929 | mutex_lock(&trace_types_lock); |
d7350c3f | 2930 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2931 | if (!iter->trace) |
d7350c3f | 2932 | goto fail; |
85a2f9b4 | 2933 | |
2b6080f2 | 2934 | *iter->trace = *tr->current_trace; |
d7350c3f | 2935 | |
79f55997 | 2936 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2937 | goto fail; |
2938 | ||
12883efb SRRH |
2939 | iter->tr = tr; |
2940 | ||
2941 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
2942 | /* Currently only the top directory has a snapshot */ |
2943 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 2944 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 2945 | else |
12883efb SRRH |
2946 | #endif |
2947 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 2948 | iter->snapshot = snapshot; |
bc0c38d1 | 2949 | iter->pos = -1; |
6484c71c | 2950 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 2951 | mutex_init(&iter->mutex); |
bc0c38d1 | 2952 | |
8bba1bf5 MM |
2953 | /* Notify the tracer early; before we stop tracing. */ |
2954 | if (iter->trace && iter->trace->open) | |
a93751ca | 2955 | iter->trace->open(iter); |
8bba1bf5 | 2956 | |
12ef7d44 | 2957 | /* Annotate start of buffers if we had overruns */ |
12883efb | 2958 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
2959 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
2960 | ||
8be0709f | 2961 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 2962 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
2963 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
2964 | ||
debdd57f HT |
2965 | /* stop the trace while dumping if we are not opening "snapshot" */ |
2966 | if (!iter->snapshot) | |
2b6080f2 | 2967 | tracing_stop_tr(tr); |
2f26ebd5 | 2968 | |
ae3b5093 | 2969 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2970 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 2971 | iter->buffer_iter[cpu] = |
12883efb | 2972 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
2973 | } |
2974 | ring_buffer_read_prepare_sync(); | |
2975 | for_each_tracing_cpu(cpu) { | |
2976 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2977 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2978 | } |
2979 | } else { | |
2980 | cpu = iter->cpu_file; | |
3928a8a2 | 2981 | iter->buffer_iter[cpu] = |
12883efb | 2982 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
2983 | ring_buffer_read_prepare_sync(); |
2984 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2985 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2986 | } |
2987 | ||
bc0c38d1 SR |
2988 | mutex_unlock(&trace_types_lock); |
2989 | ||
bc0c38d1 | 2990 | return iter; |
3928a8a2 | 2991 | |
d7350c3f | 2992 | fail: |
3928a8a2 | 2993 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2994 | kfree(iter->trace); |
6d158a81 | 2995 | kfree(iter->buffer_iter); |
93574fcc | 2996 | release: |
50e18b94 JO |
2997 | seq_release_private(inode, file); |
2998 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
2999 | } |
3000 | ||
3001 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
3002 | { | |
60a11774 SR |
3003 | if (tracing_disabled) |
3004 | return -ENODEV; | |
3005 | ||
bc0c38d1 SR |
3006 | filp->private_data = inode->i_private; |
3007 | return 0; | |
3008 | } | |
3009 | ||
2e86421d GB |
3010 | bool tracing_is_disabled(void) |
3011 | { | |
3012 | return (tracing_disabled) ? true: false; | |
3013 | } | |
3014 | ||
7b85af63 SRRH |
3015 | /* |
3016 | * Open and update trace_array ref count. | |
3017 | * Must have the current trace_array passed to it. | |
3018 | */ | |
dcc30223 | 3019 | static int tracing_open_generic_tr(struct inode *inode, struct file *filp) |
7b85af63 SRRH |
3020 | { |
3021 | struct trace_array *tr = inode->i_private; | |
3022 | ||
3023 | if (tracing_disabled) | |
3024 | return -ENODEV; | |
3025 | ||
3026 | if (trace_array_get(tr) < 0) | |
3027 | return -ENODEV; | |
3028 | ||
3029 | filp->private_data = inode->i_private; | |
3030 | ||
3031 | return 0; | |
7b85af63 SRRH |
3032 | } |
3033 | ||
4fd27358 | 3034 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 3035 | { |
6484c71c | 3036 | struct trace_array *tr = inode->i_private; |
907f2784 | 3037 | struct seq_file *m = file->private_data; |
4acd4d00 | 3038 | struct trace_iterator *iter; |
3928a8a2 | 3039 | int cpu; |
bc0c38d1 | 3040 | |
ff451961 | 3041 | if (!(file->f_mode & FMODE_READ)) { |
6484c71c | 3042 | trace_array_put(tr); |
4acd4d00 | 3043 | return 0; |
ff451961 | 3044 | } |
4acd4d00 | 3045 | |
6484c71c | 3046 | /* Writes do not use seq_file */ |
4acd4d00 | 3047 | iter = m->private; |
bc0c38d1 | 3048 | mutex_lock(&trace_types_lock); |
a695cb58 | 3049 | |
3928a8a2 SR |
3050 | for_each_tracing_cpu(cpu) { |
3051 | if (iter->buffer_iter[cpu]) | |
3052 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
3053 | } | |
3054 | ||
bc0c38d1 SR |
3055 | if (iter->trace && iter->trace->close) |
3056 | iter->trace->close(iter); | |
3057 | ||
debdd57f HT |
3058 | if (!iter->snapshot) |
3059 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 3060 | tracing_start_tr(tr); |
f77d09a3 AL |
3061 | |
3062 | __trace_array_put(tr); | |
3063 | ||
bc0c38d1 SR |
3064 | mutex_unlock(&trace_types_lock); |
3065 | ||
d7350c3f | 3066 | mutex_destroy(&iter->mutex); |
b0dfa978 | 3067 | free_cpumask_var(iter->started); |
d7350c3f | 3068 | kfree(iter->trace); |
6d158a81 | 3069 | kfree(iter->buffer_iter); |
50e18b94 | 3070 | seq_release_private(inode, file); |
ff451961 | 3071 | |
bc0c38d1 SR |
3072 | return 0; |
3073 | } | |
3074 | ||
7b85af63 SRRH |
3075 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
3076 | { | |
3077 | struct trace_array *tr = inode->i_private; | |
3078 | ||
3079 | trace_array_put(tr); | |
bc0c38d1 SR |
3080 | return 0; |
3081 | } | |
3082 | ||
7b85af63 SRRH |
3083 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
3084 | { | |
3085 | struct trace_array *tr = inode->i_private; | |
3086 | ||
3087 | trace_array_put(tr); | |
3088 | ||
3089 | return single_release(inode, file); | |
3090 | } | |
3091 | ||
bc0c38d1 SR |
3092 | static int tracing_open(struct inode *inode, struct file *file) |
3093 | { | |
6484c71c | 3094 | struct trace_array *tr = inode->i_private; |
85a2f9b4 SR |
3095 | struct trace_iterator *iter; |
3096 | int ret = 0; | |
bc0c38d1 | 3097 | |
ff451961 SRRH |
3098 | if (trace_array_get(tr) < 0) |
3099 | return -ENODEV; | |
3100 | ||
4acd4d00 | 3101 | /* If this file was open for write, then erase contents */ |
6484c71c ON |
3102 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
3103 | int cpu = tracing_get_cpu(inode); | |
3104 | ||
3105 | if (cpu == RING_BUFFER_ALL_CPUS) | |
12883efb | 3106 | tracing_reset_online_cpus(&tr->trace_buffer); |
4acd4d00 | 3107 | else |
6484c71c | 3108 | tracing_reset(&tr->trace_buffer, cpu); |
4acd4d00 | 3109 | } |
bc0c38d1 | 3110 | |
4acd4d00 | 3111 | if (file->f_mode & FMODE_READ) { |
6484c71c | 3112 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
3113 | if (IS_ERR(iter)) |
3114 | ret = PTR_ERR(iter); | |
3115 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
3116 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3117 | } | |
ff451961 SRRH |
3118 | |
3119 | if (ret < 0) | |
3120 | trace_array_put(tr); | |
3121 | ||
bc0c38d1 SR |
3122 | return ret; |
3123 | } | |
3124 | ||
e309b41d | 3125 | static void * |
bc0c38d1 SR |
3126 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3127 | { | |
f129e965 | 3128 | struct tracer *t = v; |
bc0c38d1 SR |
3129 | |
3130 | (*pos)++; | |
3131 | ||
3132 | if (t) | |
3133 | t = t->next; | |
3134 | ||
bc0c38d1 SR |
3135 | return t; |
3136 | } | |
3137 | ||
3138 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3139 | { | |
f129e965 | 3140 | struct tracer *t; |
bc0c38d1 SR |
3141 | loff_t l = 0; |
3142 | ||
3143 | mutex_lock(&trace_types_lock); | |
f129e965 | 3144 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
3145 | ; |
3146 | ||
3147 | return t; | |
3148 | } | |
3149 | ||
3150 | static void t_stop(struct seq_file *m, void *p) | |
3151 | { | |
3152 | mutex_unlock(&trace_types_lock); | |
3153 | } | |
3154 | ||
3155 | static int t_show(struct seq_file *m, void *v) | |
3156 | { | |
3157 | struct tracer *t = v; | |
3158 | ||
3159 | if (!t) | |
3160 | return 0; | |
3161 | ||
3162 | seq_printf(m, "%s", t->name); | |
3163 | if (t->next) | |
3164 | seq_putc(m, ' '); | |
3165 | else | |
3166 | seq_putc(m, '\n'); | |
3167 | ||
3168 | return 0; | |
3169 | } | |
3170 | ||
88e9d34c | 3171 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
3172 | .start = t_start, |
3173 | .next = t_next, | |
3174 | .stop = t_stop, | |
3175 | .show = t_show, | |
bc0c38d1 SR |
3176 | }; |
3177 | ||
3178 | static int show_traces_open(struct inode *inode, struct file *file) | |
3179 | { | |
60a11774 SR |
3180 | if (tracing_disabled) |
3181 | return -ENODEV; | |
3182 | ||
f129e965 | 3183 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
3184 | } |
3185 | ||
4acd4d00 SR |
3186 | static ssize_t |
3187 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
3188 | size_t count, loff_t *ppos) | |
3189 | { | |
3190 | return count; | |
3191 | } | |
3192 | ||
098c879e | 3193 | loff_t tracing_lseek(struct file *file, loff_t offset, int whence) |
364829b1 | 3194 | { |
098c879e SRRH |
3195 | int ret; |
3196 | ||
364829b1 | 3197 | if (file->f_mode & FMODE_READ) |
098c879e | 3198 | ret = seq_lseek(file, offset, whence); |
364829b1 | 3199 | else |
098c879e SRRH |
3200 | file->f_pos = ret = 0; |
3201 | ||
3202 | return ret; | |
364829b1 SP |
3203 | } |
3204 | ||
5e2336a0 | 3205 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
3206 | .open = tracing_open, |
3207 | .read = seq_read, | |
4acd4d00 | 3208 | .write = tracing_write_stub, |
098c879e | 3209 | .llseek = tracing_lseek, |
4bf39a94 | 3210 | .release = tracing_release, |
bc0c38d1 SR |
3211 | }; |
3212 | ||
5e2336a0 | 3213 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
3214 | .open = show_traces_open, |
3215 | .read = seq_read, | |
3216 | .release = seq_release, | |
b444786f | 3217 | .llseek = seq_lseek, |
c7078de1 IM |
3218 | }; |
3219 | ||
36dfe925 IM |
3220 | /* |
3221 | * The tracer itself will not take this lock, but still we want | |
3222 | * to provide a consistent cpumask to user-space: | |
3223 | */ | |
3224 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
3225 | ||
3226 | /* | |
3227 | * Temporary storage for the character representation of the | |
3228 | * CPU bitmask (and one more byte for the newline): | |
3229 | */ | |
3230 | static char mask_str[NR_CPUS + 1]; | |
3231 | ||
c7078de1 IM |
3232 | static ssize_t |
3233 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
3234 | size_t count, loff_t *ppos) | |
3235 | { | |
ccfe9e42 | 3236 | struct trace_array *tr = file_inode(filp)->i_private; |
36dfe925 | 3237 | int len; |
c7078de1 IM |
3238 | |
3239 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 3240 | |
ccfe9e42 | 3241 | len = cpumask_scnprintf(mask_str, count, tr->tracing_cpumask); |
36dfe925 IM |
3242 | if (count - len < 2) { |
3243 | count = -EINVAL; | |
3244 | goto out_err; | |
3245 | } | |
3246 | len += sprintf(mask_str + len, "\n"); | |
3247 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
3248 | ||
3249 | out_err: | |
c7078de1 IM |
3250 | mutex_unlock(&tracing_cpumask_update_lock); |
3251 | ||
3252 | return count; | |
3253 | } | |
3254 | ||
3255 | static ssize_t | |
3256 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
3257 | size_t count, loff_t *ppos) | |
3258 | { | |
ccfe9e42 | 3259 | struct trace_array *tr = file_inode(filp)->i_private; |
9e01c1b7 | 3260 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 3261 | int err, cpu; |
9e01c1b7 RR |
3262 | |
3263 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
3264 | return -ENOMEM; | |
c7078de1 | 3265 | |
9e01c1b7 | 3266 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 3267 | if (err) |
36dfe925 IM |
3268 | goto err_unlock; |
3269 | ||
215368e8 LZ |
3270 | mutex_lock(&tracing_cpumask_update_lock); |
3271 | ||
a5e25883 | 3272 | local_irq_disable(); |
0199c4e6 | 3273 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 3274 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
3275 | /* |
3276 | * Increase/decrease the disabled counter if we are | |
3277 | * about to flip a bit in the cpumask: | |
3278 | */ | |
ccfe9e42 | 3279 | if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3280 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3281 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3282 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 3283 | } |
ccfe9e42 | 3284 | if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3285 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3286 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3287 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
3288 | } |
3289 | } | |
0199c4e6 | 3290 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 3291 | local_irq_enable(); |
36dfe925 | 3292 | |
ccfe9e42 | 3293 | cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
3294 | |
3295 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 3296 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
3297 | |
3298 | return count; | |
36dfe925 IM |
3299 | |
3300 | err_unlock: | |
215368e8 | 3301 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
3302 | |
3303 | return err; | |
c7078de1 IM |
3304 | } |
3305 | ||
5e2336a0 | 3306 | static const struct file_operations tracing_cpumask_fops = { |
ccfe9e42 | 3307 | .open = tracing_open_generic_tr, |
c7078de1 IM |
3308 | .read = tracing_cpumask_read, |
3309 | .write = tracing_cpumask_write, | |
ccfe9e42 | 3310 | .release = tracing_release_generic_tr, |
b444786f | 3311 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3312 | }; |
3313 | ||
fdb372ed | 3314 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 3315 | { |
d8e83d26 | 3316 | struct tracer_opt *trace_opts; |
2b6080f2 | 3317 | struct trace_array *tr = m->private; |
d8e83d26 | 3318 | u32 tracer_flags; |
d8e83d26 | 3319 | int i; |
adf9f195 | 3320 | |
d8e83d26 | 3321 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3322 | tracer_flags = tr->current_trace->flags->val; |
3323 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 3324 | |
bc0c38d1 SR |
3325 | for (i = 0; trace_options[i]; i++) { |
3326 | if (trace_flags & (1 << i)) | |
fdb372ed | 3327 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 3328 | else |
fdb372ed | 3329 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
3330 | } |
3331 | ||
adf9f195 FW |
3332 | for (i = 0; trace_opts[i].name; i++) { |
3333 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 3334 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 3335 | else |
fdb372ed | 3336 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 3337 | } |
d8e83d26 | 3338 | mutex_unlock(&trace_types_lock); |
adf9f195 | 3339 | |
fdb372ed | 3340 | return 0; |
bc0c38d1 | 3341 | } |
bc0c38d1 | 3342 | |
8c1a49ae | 3343 | static int __set_tracer_option(struct trace_array *tr, |
8d18eaaf LZ |
3344 | struct tracer_flags *tracer_flags, |
3345 | struct tracer_opt *opts, int neg) | |
3346 | { | |
8c1a49ae | 3347 | struct tracer *trace = tr->current_trace; |
8d18eaaf | 3348 | int ret; |
bc0c38d1 | 3349 | |
8c1a49ae | 3350 | ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); |
8d18eaaf LZ |
3351 | if (ret) |
3352 | return ret; | |
3353 | ||
3354 | if (neg) | |
3355 | tracer_flags->val &= ~opts->bit; | |
3356 | else | |
3357 | tracer_flags->val |= opts->bit; | |
3358 | return 0; | |
bc0c38d1 SR |
3359 | } |
3360 | ||
adf9f195 | 3361 | /* Try to assign a tracer specific option */ |
8c1a49ae | 3362 | static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) |
adf9f195 | 3363 | { |
8c1a49ae | 3364 | struct tracer *trace = tr->current_trace; |
7770841e | 3365 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 3366 | struct tracer_opt *opts = NULL; |
8d18eaaf | 3367 | int i; |
adf9f195 | 3368 | |
7770841e Z |
3369 | for (i = 0; tracer_flags->opts[i].name; i++) { |
3370 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 3371 | |
8d18eaaf | 3372 | if (strcmp(cmp, opts->name) == 0) |
8c1a49ae | 3373 | return __set_tracer_option(tr, trace->flags, opts, neg); |
adf9f195 | 3374 | } |
adf9f195 | 3375 | |
8d18eaaf | 3376 | return -EINVAL; |
adf9f195 FW |
3377 | } |
3378 | ||
613f04a0 SRRH |
3379 | /* Some tracers require overwrite to stay enabled */ |
3380 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
3381 | { | |
3382 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
3383 | return -1; | |
3384 | ||
3385 | return 0; | |
3386 | } | |
3387 | ||
2b6080f2 | 3388 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
3389 | { |
3390 | /* do nothing if flag is already set */ | |
3391 | if (!!(trace_flags & mask) == !!enabled) | |
613f04a0 SRRH |
3392 | return 0; |
3393 | ||
3394 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 SR |
3395 | if (tr->current_trace->flag_changed) |
3396 | if (tr->current_trace->flag_changed(tr->current_trace, mask, !!enabled)) | |
613f04a0 | 3397 | return -EINVAL; |
af4617bd SR |
3398 | |
3399 | if (enabled) | |
3400 | trace_flags |= mask; | |
3401 | else | |
3402 | trace_flags &= ~mask; | |
e870e9a1 LZ |
3403 | |
3404 | if (mask == TRACE_ITER_RECORD_CMD) | |
3405 | trace_event_enable_cmd_record(enabled); | |
750912fa | 3406 | |
80902822 | 3407 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 3408 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 3409 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 3410 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
3411 | #endif |
3412 | } | |
81698831 SR |
3413 | |
3414 | if (mask == TRACE_ITER_PRINTK) | |
3415 | trace_printk_start_stop_comm(enabled); | |
613f04a0 SRRH |
3416 | |
3417 | return 0; | |
af4617bd SR |
3418 | } |
3419 | ||
2b6080f2 | 3420 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 3421 | { |
8d18eaaf | 3422 | char *cmp; |
bc0c38d1 | 3423 | int neg = 0; |
613f04a0 | 3424 | int ret = -ENODEV; |
bc0c38d1 SR |
3425 | int i; |
3426 | ||
7bcfaf54 | 3427 | cmp = strstrip(option); |
bc0c38d1 | 3428 | |
8d18eaaf | 3429 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3430 | neg = 1; |
3431 | cmp += 2; | |
3432 | } | |
3433 | ||
69d34da2 SRRH |
3434 | mutex_lock(&trace_types_lock); |
3435 | ||
bc0c38d1 | 3436 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3437 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3438 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3439 | break; |
3440 | } | |
3441 | } | |
adf9f195 FW |
3442 | |
3443 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3444 | if (!trace_options[i]) |
8c1a49ae | 3445 | ret = set_tracer_option(tr, cmp, neg); |
69d34da2 SRRH |
3446 | |
3447 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3448 | |
7bcfaf54 SR |
3449 | return ret; |
3450 | } | |
3451 | ||
3452 | static ssize_t | |
3453 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3454 | size_t cnt, loff_t *ppos) | |
3455 | { | |
2b6080f2 SR |
3456 | struct seq_file *m = filp->private_data; |
3457 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3458 | char buf[64]; |
613f04a0 | 3459 | int ret; |
7bcfaf54 SR |
3460 | |
3461 | if (cnt >= sizeof(buf)) | |
3462 | return -EINVAL; | |
3463 | ||
3464 | if (copy_from_user(&buf, ubuf, cnt)) | |
3465 | return -EFAULT; | |
3466 | ||
a8dd2176 SR |
3467 | buf[cnt] = 0; |
3468 | ||
2b6080f2 | 3469 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
3470 | if (ret < 0) |
3471 | return ret; | |
7bcfaf54 | 3472 | |
cf8517cf | 3473 | *ppos += cnt; |
bc0c38d1 SR |
3474 | |
3475 | return cnt; | |
3476 | } | |
3477 | ||
fdb372ed LZ |
3478 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
3479 | { | |
7b85af63 | 3480 | struct trace_array *tr = inode->i_private; |
f77d09a3 | 3481 | int ret; |
7b85af63 | 3482 | |
fdb372ed LZ |
3483 | if (tracing_disabled) |
3484 | return -ENODEV; | |
2b6080f2 | 3485 | |
7b85af63 SRRH |
3486 | if (trace_array_get(tr) < 0) |
3487 | return -ENODEV; | |
3488 | ||
f77d09a3 AL |
3489 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
3490 | if (ret < 0) | |
3491 | trace_array_put(tr); | |
3492 | ||
3493 | return ret; | |
fdb372ed LZ |
3494 | } |
3495 | ||
5e2336a0 | 3496 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
3497 | .open = tracing_trace_options_open, |
3498 | .read = seq_read, | |
3499 | .llseek = seq_lseek, | |
7b85af63 | 3500 | .release = tracing_single_release_tr, |
ee6bce52 | 3501 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
3502 | }; |
3503 | ||
7bd2f24c IM |
3504 | static const char readme_msg[] = |
3505 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
3506 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
3507 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
3508 | " Important files:\n" | |
3509 | " trace\t\t\t- The static contents of the buffer\n" | |
3510 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
3511 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
3512 | " current_tracer\t- function and latency tracers\n" | |
3513 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
3514 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" | |
3515 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
3516 | " trace_clock\t\t-change the clock used to order events\n" | |
3517 | " local: Per cpu clock but may not be synced across CPUs\n" | |
3518 | " global: Synced across CPUs but slows tracing down.\n" | |
3519 | " counter: Not a clock, but just an increment\n" | |
3520 | " uptime: Jiffy counter from time of boot\n" | |
3521 | " perf: Same clock that perf events use\n" | |
3522 | #ifdef CONFIG_X86_64 | |
3523 | " x86-tsc: TSC cycle counter\n" | |
3524 | #endif | |
3525 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" | |
3526 | " tracing_cpumask\t- Limit which CPUs to trace\n" | |
3527 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
3528 | "\t\t\t Remove sub-buffer with rmdir\n" | |
3529 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
71485c45 SRRH |
3530 | "\t\t\t Disable an option by adding a suffix 'no' to the\n" |
3531 | "\t\t\t option name\n" | |
22f45649 SRRH |
3532 | #ifdef CONFIG_DYNAMIC_FTRACE |
3533 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
71485c45 SRRH |
3534 | " set_ftrace_filter\t- echo function name in here to only trace these\n" |
3535 | "\t\t\t functions\n" | |
3536 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3537 | "\t modules: Can select a group via module\n" | |
3538 | "\t Format: :mod:<module-name>\n" | |
3539 | "\t example: echo :mod:ext3 > set_ftrace_filter\n" | |
3540 | "\t triggers: a command to perform when function is hit\n" | |
3541 | "\t Format: <function>:<trigger>[:count]\n" | |
3542 | "\t trigger: traceon, traceoff\n" | |
3543 | "\t\t enable_event:<system>:<event>\n" | |
3544 | "\t\t disable_event:<system>:<event>\n" | |
22f45649 | 3545 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3546 | "\t\t stacktrace\n" |
22f45649 SRRH |
3547 | #endif |
3548 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3549 | "\t\t snapshot\n" |
22f45649 | 3550 | #endif |
71485c45 SRRH |
3551 | "\t example: echo do_fault:traceoff > set_ftrace_filter\n" |
3552 | "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
3553 | "\t The first one will disable tracing every time do_fault is hit\n" | |
3554 | "\t The second will disable tracing at most 3 times when do_trap is hit\n" | |
3555 | "\t The first time do trap is hit and it disables tracing, the\n" | |
3556 | "\t counter will decrement to 2. If tracing is already disabled,\n" | |
3557 | "\t the counter will not decrement. It only decrements when the\n" | |
3558 | "\t trigger did work\n" | |
3559 | "\t To remove trigger without count:\n" | |
3560 | "\t echo '!<function>:<trigger> > set_ftrace_filter\n" | |
3561 | "\t To remove trigger with a count:\n" | |
3562 | "\t echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
22f45649 | 3563 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" |
71485c45 SRRH |
3564 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" |
3565 | "\t modules: Can select a group via module command :mod:\n" | |
3566 | "\t Does not accept triggers\n" | |
22f45649 SRRH |
3567 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
3568 | #ifdef CONFIG_FUNCTION_TRACER | |
71485c45 SRRH |
3569 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" |
3570 | "\t\t (function)\n" | |
22f45649 SRRH |
3571 | #endif |
3572 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
3573 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
3574 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" | |
3575 | #endif | |
3576 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 SRRH |
3577 | "\n snapshot\t\t- Like 'trace' but shows the content of the static\n" |
3578 | "\t\t\t snapshot buffer. Read the contents for more\n" | |
3579 | "\t\t\t information\n" | |
22f45649 | 3580 | #endif |
991821c8 | 3581 | #ifdef CONFIG_STACK_TRACER |
22f45649 SRRH |
3582 | " stack_trace\t\t- Shows the max stack trace when active\n" |
3583 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
71485c45 SRRH |
3584 | "\t\t\t Write into this file to reset the max size (trigger a\n" |
3585 | "\t\t\t new trace)\n" | |
22f45649 | 3586 | #ifdef CONFIG_DYNAMIC_FTRACE |
71485c45 SRRH |
3587 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n" |
3588 | "\t\t\t traces\n" | |
22f45649 | 3589 | #endif |
991821c8 | 3590 | #endif /* CONFIG_STACK_TRACER */ |
26f25564 TZ |
3591 | " events/\t\t- Directory containing all trace event subsystems:\n" |
3592 | " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" | |
3593 | " events/<system>/\t- Directory containing all trace events for <system>:\n" | |
71485c45 SRRH |
3594 | " enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n" |
3595 | "\t\t\t events\n" | |
26f25564 | 3596 | " filter\t\t- If set, only events passing filter are traced\n" |
71485c45 SRRH |
3597 | " events/<system>/<event>/\t- Directory containing control files for\n" |
3598 | "\t\t\t <event>:\n" | |
26f25564 TZ |
3599 | " enable\t\t- Write 0/1 to enable/disable tracing of <event>\n" |
3600 | " filter\t\t- If set, only events passing filter are traced\n" | |
3601 | " trigger\t\t- If set, a command to perform when event is hit\n" | |
71485c45 SRRH |
3602 | "\t Format: <trigger>[:count][if <filter>]\n" |
3603 | "\t trigger: traceon, traceoff\n" | |
3604 | "\t enable_event:<system>:<event>\n" | |
3605 | "\t disable_event:<system>:<event>\n" | |
26f25564 | 3606 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3607 | "\t\t stacktrace\n" |
26f25564 TZ |
3608 | #endif |
3609 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3610 | "\t\t snapshot\n" |
26f25564 | 3611 | #endif |
71485c45 SRRH |
3612 | "\t example: echo traceoff > events/block/block_unplug/trigger\n" |
3613 | "\t echo traceoff:3 > events/block/block_unplug/trigger\n" | |
3614 | "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" | |
3615 | "\t events/block/block_unplug/trigger\n" | |
3616 | "\t The first disables tracing every time block_unplug is hit.\n" | |
3617 | "\t The second disables tracing the first 3 times block_unplug is hit.\n" | |
3618 | "\t The third enables the kmalloc event the first 3 times block_unplug\n" | |
3619 | "\t is hit and has value of greater than 1 for the 'nr_rq' event field.\n" | |
3620 | "\t Like function triggers, the counter is only decremented if it\n" | |
3621 | "\t enabled or disabled tracing.\n" | |
3622 | "\t To remove a trigger without a count:\n" | |
3623 | "\t echo '!<trigger> > <system>/<event>/trigger\n" | |
3624 | "\t To remove a trigger with a count:\n" | |
3625 | "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" | |
3626 | "\t Filters can be ignored when removing a trigger.\n" | |
7bd2f24c IM |
3627 | ; |
3628 | ||
3629 | static ssize_t | |
3630 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
3631 | size_t cnt, loff_t *ppos) | |
3632 | { | |
3633 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
3634 | readme_msg, strlen(readme_msg)); | |
3635 | } | |
3636 | ||
5e2336a0 | 3637 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
3638 | .open = tracing_open_generic, |
3639 | .read = tracing_readme_read, | |
b444786f | 3640 | .llseek = generic_file_llseek, |
7bd2f24c IM |
3641 | }; |
3642 | ||
69abe6a5 AP |
3643 | static ssize_t |
3644 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
3645 | size_t cnt, loff_t *ppos) | |
3646 | { | |
3647 | char *buf_comm; | |
3648 | char *file_buf; | |
3649 | char *buf; | |
3650 | int len = 0; | |
3651 | int pid; | |
3652 | int i; | |
3653 | ||
3654 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
3655 | if (!file_buf) | |
3656 | return -ENOMEM; | |
3657 | ||
3658 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
3659 | if (!buf_comm) { | |
3660 | kfree(file_buf); | |
3661 | return -ENOMEM; | |
3662 | } | |
3663 | ||
3664 | buf = file_buf; | |
3665 | ||
3666 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
3667 | int r; | |
3668 | ||
3669 | pid = map_cmdline_to_pid[i]; | |
3670 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
3671 | continue; | |
3672 | ||
3673 | trace_find_cmdline(pid, buf_comm); | |
3674 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
3675 | buf += r; | |
3676 | len += r; | |
3677 | } | |
3678 | ||
3679 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
3680 | file_buf, len); | |
3681 | ||
3682 | kfree(file_buf); | |
3683 | kfree(buf_comm); | |
3684 | ||
3685 | return len; | |
3686 | } | |
3687 | ||
3688 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
3689 | .open = tracing_open_generic, | |
3690 | .read = tracing_saved_cmdlines_read, | |
b444786f | 3691 | .llseek = generic_file_llseek, |
69abe6a5 AP |
3692 | }; |
3693 | ||
bc0c38d1 SR |
3694 | static ssize_t |
3695 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
3696 | size_t cnt, loff_t *ppos) | |
3697 | { | |
2b6080f2 | 3698 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 3699 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
3700 | int r; |
3701 | ||
3702 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 3703 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
3704 | mutex_unlock(&trace_types_lock); |
3705 | ||
4bf39a94 | 3706 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3707 | } |
3708 | ||
b6f11df2 ACM |
3709 | int tracer_init(struct tracer *t, struct trace_array *tr) |
3710 | { | |
12883efb | 3711 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
3712 | return t->init(tr); |
3713 | } | |
3714 | ||
12883efb | 3715 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
3716 | { |
3717 | int cpu; | |
737223fb | 3718 | |
438ced17 | 3719 | for_each_tracing_cpu(cpu) |
12883efb | 3720 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
3721 | } |
3722 | ||
12883efb | 3723 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 3724 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
3725 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
3726 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
3727 | { |
3728 | int cpu, ret = 0; | |
3729 | ||
3730 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
3731 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
3732 | ret = ring_buffer_resize(trace_buf->buffer, |
3733 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
3734 | if (ret < 0) |
3735 | break; | |
12883efb SRRH |
3736 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
3737 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
3738 | } |
3739 | } else { | |
12883efb SRRH |
3740 | ret = ring_buffer_resize(trace_buf->buffer, |
3741 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 3742 | if (ret == 0) |
12883efb SRRH |
3743 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
3744 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
3745 | } |
3746 | ||
3747 | return ret; | |
3748 | } | |
12883efb | 3749 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 3750 | |
2b6080f2 SR |
3751 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
3752 | unsigned long size, int cpu) | |
73c5162a SR |
3753 | { |
3754 | int ret; | |
3755 | ||
3756 | /* | |
3757 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3758 | * we use the size that was given, and we can forget about |
3759 | * expanding it later. | |
73c5162a | 3760 | */ |
55034cd6 | 3761 | ring_buffer_expanded = true; |
73c5162a | 3762 | |
b382ede6 | 3763 | /* May be called before buffers are initialized */ |
12883efb | 3764 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
3765 | return 0; |
3766 | ||
12883efb | 3767 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
3768 | if (ret < 0) |
3769 | return ret; | |
3770 | ||
12883efb | 3771 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
3772 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
3773 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
3774 | goto out; |
3775 | ||
12883efb | 3776 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 3777 | if (ret < 0) { |
12883efb SRRH |
3778 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
3779 | &tr->trace_buffer, cpu); | |
73c5162a | 3780 | if (r < 0) { |
a123c52b SR |
3781 | /* |
3782 | * AARGH! We are left with different | |
3783 | * size max buffer!!!! | |
3784 | * The max buffer is our "snapshot" buffer. | |
3785 | * When a tracer needs a snapshot (one of the | |
3786 | * latency tracers), it swaps the max buffer | |
3787 | * with the saved snap shot. We succeeded to | |
3788 | * update the size of the main buffer, but failed to | |
3789 | * update the size of the max buffer. But when we tried | |
3790 | * to reset the main buffer to the original size, we | |
3791 | * failed there too. This is very unlikely to | |
3792 | * happen, but if it does, warn and kill all | |
3793 | * tracing. | |
3794 | */ | |
73c5162a SR |
3795 | WARN_ON(1); |
3796 | tracing_disabled = 1; | |
3797 | } | |
3798 | return ret; | |
3799 | } | |
3800 | ||
438ced17 | 3801 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3802 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 3803 | else |
12883efb | 3804 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 3805 | |
ef710e10 | 3806 | out: |
12883efb SRRH |
3807 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
3808 | ||
438ced17 | 3809 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3810 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 3811 | else |
12883efb | 3812 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
3813 | |
3814 | return ret; | |
3815 | } | |
3816 | ||
2b6080f2 SR |
3817 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
3818 | unsigned long size, int cpu_id) | |
4f271a2a | 3819 | { |
83f40318 | 3820 | int ret = size; |
4f271a2a VN |
3821 | |
3822 | mutex_lock(&trace_types_lock); | |
3823 | ||
438ced17 VN |
3824 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
3825 | /* make sure, this cpu is enabled in the mask */ | |
3826 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
3827 | ret = -EINVAL; | |
3828 | goto out; | |
3829 | } | |
3830 | } | |
4f271a2a | 3831 | |
2b6080f2 | 3832 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
3833 | if (ret < 0) |
3834 | ret = -ENOMEM; | |
3835 | ||
438ced17 | 3836 | out: |
4f271a2a VN |
3837 | mutex_unlock(&trace_types_lock); |
3838 | ||
3839 | return ret; | |
3840 | } | |
3841 | ||
ef710e10 | 3842 | |
1852fcce SR |
3843 | /** |
3844 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
3845 | * | |
3846 | * To save on memory when the tracing is never used on a system with it | |
3847 | * configured in. The ring buffers are set to a minimum size. But once | |
3848 | * a user starts to use the tracing facility, then they need to grow | |
3849 | * to their default size. | |
3850 | * | |
3851 | * This function is to be called when a tracer is about to be used. | |
3852 | */ | |
3853 | int tracing_update_buffers(void) | |
3854 | { | |
3855 | int ret = 0; | |
3856 | ||
1027fcb2 | 3857 | mutex_lock(&trace_types_lock); |
1852fcce | 3858 | if (!ring_buffer_expanded) |
2b6080f2 | 3859 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 3860 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 3861 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
3862 | |
3863 | return ret; | |
3864 | } | |
3865 | ||
577b785f SR |
3866 | struct trace_option_dentry; |
3867 | ||
3868 | static struct trace_option_dentry * | |
2b6080f2 | 3869 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f SR |
3870 | |
3871 | static void | |
3872 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
3873 | ||
b2821ae6 | 3874 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 3875 | { |
577b785f | 3876 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
3877 | struct trace_array *tr = &global_trace; |
3878 | struct tracer *t; | |
12883efb | 3879 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 3880 | bool had_max_tr; |
12883efb | 3881 | #endif |
d9e54076 | 3882 | int ret = 0; |
bc0c38d1 | 3883 | |
1027fcb2 SR |
3884 | mutex_lock(&trace_types_lock); |
3885 | ||
73c5162a | 3886 | if (!ring_buffer_expanded) { |
2b6080f2 | 3887 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 3888 | RING_BUFFER_ALL_CPUS); |
73c5162a | 3889 | if (ret < 0) |
59f586db | 3890 | goto out; |
73c5162a SR |
3891 | ret = 0; |
3892 | } | |
3893 | ||
bc0c38d1 SR |
3894 | for (t = trace_types; t; t = t->next) { |
3895 | if (strcmp(t->name, buf) == 0) | |
3896 | break; | |
3897 | } | |
c2931e05 FW |
3898 | if (!t) { |
3899 | ret = -EINVAL; | |
3900 | goto out; | |
3901 | } | |
2b6080f2 | 3902 | if (t == tr->current_trace) |
bc0c38d1 SR |
3903 | goto out; |
3904 | ||
9f029e83 | 3905 | trace_branch_disable(); |
613f04a0 | 3906 | |
2b6080f2 | 3907 | tr->current_trace->enabled = false; |
613f04a0 | 3908 | |
2b6080f2 SR |
3909 | if (tr->current_trace->reset) |
3910 | tr->current_trace->reset(tr); | |
34600f0e | 3911 | |
12883efb | 3912 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 3913 | tr->current_trace = &nop_trace; |
34600f0e | 3914 | |
45ad21ca SRRH |
3915 | #ifdef CONFIG_TRACER_MAX_TRACE |
3916 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
3917 | |
3918 | if (had_max_tr && !t->use_max_tr) { | |
3919 | /* | |
3920 | * We need to make sure that the update_max_tr sees that | |
3921 | * current_trace changed to nop_trace to keep it from | |
3922 | * swapping the buffers after we resize it. | |
3923 | * The update_max_tr is called from interrupts disabled | |
3924 | * so a synchronized_sched() is sufficient. | |
3925 | */ | |
3926 | synchronize_sched(); | |
3209cff4 | 3927 | free_snapshot(tr); |
ef710e10 | 3928 | } |
12883efb | 3929 | #endif |
577b785f SR |
3930 | destroy_trace_option_files(topts); |
3931 | ||
2b6080f2 | 3932 | topts = create_trace_option_files(tr, t); |
12883efb SRRH |
3933 | |
3934 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 3935 | if (t->use_max_tr && !had_max_tr) { |
3209cff4 | 3936 | ret = alloc_snapshot(tr); |
d60da506 HT |
3937 | if (ret < 0) |
3938 | goto out; | |
ef710e10 | 3939 | } |
12883efb | 3940 | #endif |
577b785f | 3941 | |
1c80025a | 3942 | if (t->init) { |
b6f11df2 | 3943 | ret = tracer_init(t, tr); |
1c80025a FW |
3944 | if (ret) |
3945 | goto out; | |
3946 | } | |
bc0c38d1 | 3947 | |
2b6080f2 SR |
3948 | tr->current_trace = t; |
3949 | tr->current_trace->enabled = true; | |
9f029e83 | 3950 | trace_branch_enable(tr); |
bc0c38d1 SR |
3951 | out: |
3952 | mutex_unlock(&trace_types_lock); | |
3953 | ||
d9e54076 PZ |
3954 | return ret; |
3955 | } | |
3956 | ||
3957 | static ssize_t | |
3958 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
3959 | size_t cnt, loff_t *ppos) | |
3960 | { | |
ee6c2c1b | 3961 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
3962 | int i; |
3963 | size_t ret; | |
e6e7a65a FW |
3964 | int err; |
3965 | ||
3966 | ret = cnt; | |
d9e54076 | 3967 | |
ee6c2c1b LZ |
3968 | if (cnt > MAX_TRACER_SIZE) |
3969 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
3970 | |
3971 | if (copy_from_user(&buf, ubuf, cnt)) | |
3972 | return -EFAULT; | |
3973 | ||
3974 | buf[cnt] = 0; | |
3975 | ||
3976 | /* strip ending whitespace. */ | |
3977 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
3978 | buf[i] = 0; | |
3979 | ||
e6e7a65a FW |
3980 | err = tracing_set_tracer(buf); |
3981 | if (err) | |
3982 | return err; | |
d9e54076 | 3983 | |
cf8517cf | 3984 | *ppos += ret; |
bc0c38d1 | 3985 | |
c2931e05 | 3986 | return ret; |
bc0c38d1 SR |
3987 | } |
3988 | ||
3989 | static ssize_t | |
3990 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
3991 | size_t cnt, loff_t *ppos) | |
3992 | { | |
3993 | unsigned long *ptr = filp->private_data; | |
3994 | char buf[64]; | |
3995 | int r; | |
3996 | ||
cffae437 | 3997 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 3998 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
3999 | if (r > sizeof(buf)) |
4000 | r = sizeof(buf); | |
4bf39a94 | 4001 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
4002 | } |
4003 | ||
4004 | static ssize_t | |
4005 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
4006 | size_t cnt, loff_t *ppos) | |
4007 | { | |
5e39841c | 4008 | unsigned long *ptr = filp->private_data; |
5e39841c | 4009 | unsigned long val; |
c6caeeb1 | 4010 | int ret; |
bc0c38d1 | 4011 | |
22fe9b54 PH |
4012 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4013 | if (ret) | |
c6caeeb1 | 4014 | return ret; |
bc0c38d1 SR |
4015 | |
4016 | *ptr = val * 1000; | |
4017 | ||
4018 | return cnt; | |
4019 | } | |
4020 | ||
b3806b43 SR |
4021 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
4022 | { | |
15544209 | 4023 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4024 | struct trace_iterator *iter; |
b04cc6b1 | 4025 | int ret = 0; |
b3806b43 SR |
4026 | |
4027 | if (tracing_disabled) | |
4028 | return -ENODEV; | |
4029 | ||
7b85af63 SRRH |
4030 | if (trace_array_get(tr) < 0) |
4031 | return -ENODEV; | |
4032 | ||
b04cc6b1 FW |
4033 | mutex_lock(&trace_types_lock); |
4034 | ||
b3806b43 SR |
4035 | /* create a buffer to store the information to pass to userspace */ |
4036 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
4037 | if (!iter) { |
4038 | ret = -ENOMEM; | |
f77d09a3 | 4039 | __trace_array_put(tr); |
b04cc6b1 FW |
4040 | goto out; |
4041 | } | |
b3806b43 | 4042 | |
d7350c3f FW |
4043 | /* |
4044 | * We make a copy of the current tracer to avoid concurrent | |
4045 | * changes on it while we are reading. | |
4046 | */ | |
4047 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
4048 | if (!iter->trace) { | |
4049 | ret = -ENOMEM; | |
4050 | goto fail; | |
4051 | } | |
2b6080f2 | 4052 | *iter->trace = *tr->current_trace; |
d7350c3f | 4053 | |
4462344e | 4054 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 4055 | ret = -ENOMEM; |
d7350c3f | 4056 | goto fail; |
4462344e RR |
4057 | } |
4058 | ||
a309720c | 4059 | /* trace pipe does not show start of buffer */ |
4462344e | 4060 | cpumask_setall(iter->started); |
a309720c | 4061 | |
112f38a7 SR |
4062 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
4063 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
4064 | ||
8be0709f | 4065 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 4066 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
4067 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
4068 | ||
15544209 ON |
4069 | iter->tr = tr; |
4070 | iter->trace_buffer = &tr->trace_buffer; | |
4071 | iter->cpu_file = tracing_get_cpu(inode); | |
d7350c3f | 4072 | mutex_init(&iter->mutex); |
b3806b43 SR |
4073 | filp->private_data = iter; |
4074 | ||
107bad8b SR |
4075 | if (iter->trace->pipe_open) |
4076 | iter->trace->pipe_open(iter); | |
107bad8b | 4077 | |
b444786f | 4078 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
4079 | out: |
4080 | mutex_unlock(&trace_types_lock); | |
4081 | return ret; | |
d7350c3f FW |
4082 | |
4083 | fail: | |
4084 | kfree(iter->trace); | |
4085 | kfree(iter); | |
7b85af63 | 4086 | __trace_array_put(tr); |
d7350c3f FW |
4087 | mutex_unlock(&trace_types_lock); |
4088 | return ret; | |
b3806b43 SR |
4089 | } |
4090 | ||
4091 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
4092 | { | |
4093 | struct trace_iterator *iter = file->private_data; | |
15544209 | 4094 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4095 | |
b04cc6b1 FW |
4096 | mutex_lock(&trace_types_lock); |
4097 | ||
29bf4a5e | 4098 | if (iter->trace->pipe_close) |
c521efd1 SR |
4099 | iter->trace->pipe_close(iter); |
4100 | ||
b04cc6b1 FW |
4101 | mutex_unlock(&trace_types_lock); |
4102 | ||
4462344e | 4103 | free_cpumask_var(iter->started); |
d7350c3f FW |
4104 | mutex_destroy(&iter->mutex); |
4105 | kfree(iter->trace); | |
b3806b43 | 4106 | kfree(iter); |
b3806b43 | 4107 | |
7b85af63 SRRH |
4108 | trace_array_put(tr); |
4109 | ||
b3806b43 SR |
4110 | return 0; |
4111 | } | |
4112 | ||
2a2cc8f7 | 4113 | static unsigned int |
cc60cdc9 | 4114 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 4115 | { |
15693458 SRRH |
4116 | /* Iterators are static, they should be filled or empty */ |
4117 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
4118 | return POLLIN | POLLRDNORM; | |
2a2cc8f7 | 4119 | |
15693458 | 4120 | if (trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
4121 | /* |
4122 | * Always select as readable when in blocking mode | |
4123 | */ | |
4124 | return POLLIN | POLLRDNORM; | |
15693458 | 4125 | else |
12883efb | 4126 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 4127 | filp, poll_table); |
2a2cc8f7 | 4128 | } |
2a2cc8f7 | 4129 | |
cc60cdc9 SR |
4130 | static unsigned int |
4131 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
4132 | { | |
4133 | struct trace_iterator *iter = filp->private_data; | |
4134 | ||
4135 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
4136 | } |
4137 | ||
6eaaa5d5 FW |
4138 | /* |
4139 | * This is a make-shift waitqueue. | |
4140 | * A tracer might use this callback on some rare cases: | |
4141 | * | |
4142 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
4143 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
4144 | * 2) the function tracers, trace all functions, we don't want | |
4145 | * the overhead of calling wake_up and friends | |
4146 | * (and tracing them too) | |
4147 | * | |
4148 | * Anyway, this is really very primitive wakeup. | |
4149 | */ | |
4150 | void poll_wait_pipe(struct trace_iterator *iter) | |
4151 | { | |
4152 | set_current_state(TASK_INTERRUPTIBLE); | |
4153 | /* sleep for 100 msecs, and try again. */ | |
4154 | schedule_timeout(HZ / 10); | |
4155 | } | |
4156 | ||
ff98781b EGM |
4157 | /* Must be called with trace_types_lock mutex held. */ |
4158 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
4159 | { |
4160 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 4161 | |
b3806b43 | 4162 | while (trace_empty(iter)) { |
2dc8f095 | 4163 | |
107bad8b | 4164 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 4165 | return -EAGAIN; |
107bad8b | 4166 | } |
2dc8f095 | 4167 | |
d7350c3f | 4168 | mutex_unlock(&iter->mutex); |
107bad8b | 4169 | |
6eaaa5d5 | 4170 | iter->trace->wait_pipe(iter); |
b3806b43 | 4171 | |
d7350c3f | 4172 | mutex_lock(&iter->mutex); |
107bad8b | 4173 | |
6eaaa5d5 | 4174 | if (signal_pending(current)) |
ff98781b | 4175 | return -EINTR; |
b3806b43 SR |
4176 | |
4177 | /* | |
250bfd3d | 4178 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
4179 | * We still block if tracing is disabled, but we have never |
4180 | * read anything. This allows a user to cat this file, and | |
4181 | * then enable tracing. But after we have read something, | |
4182 | * we give an EOF when tracing is again disabled. | |
4183 | * | |
4184 | * iter->pos will be 0 if we haven't read anything. | |
4185 | */ | |
10246fa3 | 4186 | if (!tracing_is_on() && iter->pos) |
b3806b43 | 4187 | break; |
b3806b43 SR |
4188 | } |
4189 | ||
ff98781b EGM |
4190 | return 1; |
4191 | } | |
4192 | ||
4193 | /* | |
4194 | * Consumer reader. | |
4195 | */ | |
4196 | static ssize_t | |
4197 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
4198 | size_t cnt, loff_t *ppos) | |
4199 | { | |
4200 | struct trace_iterator *iter = filp->private_data; | |
2b6080f2 | 4201 | struct trace_array *tr = iter->tr; |
ff98781b EGM |
4202 | ssize_t sret; |
4203 | ||
4204 | /* return any leftover data */ | |
4205 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
4206 | if (sret != -EBUSY) | |
4207 | return sret; | |
4208 | ||
f9520750 | 4209 | trace_seq_init(&iter->seq); |
ff98781b | 4210 | |
d7350c3f | 4211 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 4212 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4213 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4214 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4215 | mutex_unlock(&trace_types_lock); |
4216 | ||
4217 | /* | |
4218 | * Avoid more than one consumer on a single file descriptor | |
4219 | * This is just a matter of traces coherency, the ring buffer itself | |
4220 | * is protected. | |
4221 | */ | |
4222 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
4223 | if (iter->trace->read) { |
4224 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
4225 | if (sret) | |
4226 | goto out; | |
4227 | } | |
4228 | ||
4229 | waitagain: | |
4230 | sret = tracing_wait_pipe(filp); | |
4231 | if (sret <= 0) | |
4232 | goto out; | |
4233 | ||
b3806b43 | 4234 | /* stop when tracing is finished */ |
ff98781b EGM |
4235 | if (trace_empty(iter)) { |
4236 | sret = 0; | |
107bad8b | 4237 | goto out; |
ff98781b | 4238 | } |
b3806b43 SR |
4239 | |
4240 | if (cnt >= PAGE_SIZE) | |
4241 | cnt = PAGE_SIZE - 1; | |
4242 | ||
53d0aa77 | 4243 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
4244 | memset(&iter->seq, 0, |
4245 | sizeof(struct trace_iterator) - | |
4246 | offsetof(struct trace_iterator, seq)); | |
ed5467da | 4247 | cpumask_clear(iter->started); |
4823ed7e | 4248 | iter->pos = -1; |
b3806b43 | 4249 | |
4f535968 | 4250 | trace_event_read_lock(); |
7e53bd42 | 4251 | trace_access_lock(iter->cpu_file); |
955b61e5 | 4252 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 4253 | enum print_line_t ret; |
088b1e42 SR |
4254 | int len = iter->seq.len; |
4255 | ||
f9896bf3 | 4256 | ret = print_trace_line(iter); |
2c4f035f | 4257 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
4258 | /* don't print partial lines */ |
4259 | iter->seq.len = len; | |
b3806b43 | 4260 | break; |
088b1e42 | 4261 | } |
b91facc3 FW |
4262 | if (ret != TRACE_TYPE_NO_CONSUME) |
4263 | trace_consume(iter); | |
b3806b43 SR |
4264 | |
4265 | if (iter->seq.len >= cnt) | |
4266 | break; | |
ee5e51f5 JO |
4267 | |
4268 | /* | |
4269 | * Setting the full flag means we reached the trace_seq buffer | |
4270 | * size and we should leave by partial output condition above. | |
4271 | * One of the trace_seq_* functions is not used properly. | |
4272 | */ | |
4273 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
4274 | iter->ent->type); | |
b3806b43 | 4275 | } |
7e53bd42 | 4276 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4277 | trace_event_read_unlock(); |
b3806b43 | 4278 | |
b3806b43 | 4279 | /* Now copy what we have to the user */ |
6c6c2796 PP |
4280 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
4281 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 4282 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
4283 | |
4284 | /* | |
25985edc | 4285 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
4286 | * entries, go back to wait for more entries. |
4287 | */ | |
6c6c2796 | 4288 | if (sret == -EBUSY) |
9ff4b974 | 4289 | goto waitagain; |
b3806b43 | 4290 | |
107bad8b | 4291 | out: |
d7350c3f | 4292 | mutex_unlock(&iter->mutex); |
107bad8b | 4293 | |
6c6c2796 | 4294 | return sret; |
b3806b43 SR |
4295 | } |
4296 | ||
3c56819b EGM |
4297 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, |
4298 | unsigned int idx) | |
4299 | { | |
4300 | __free_page(spd->pages[idx]); | |
4301 | } | |
4302 | ||
28dfef8f | 4303 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
4304 | .can_merge = 0, |
4305 | .map = generic_pipe_buf_map, | |
4306 | .unmap = generic_pipe_buf_unmap, | |
4307 | .confirm = generic_pipe_buf_confirm, | |
92fdd98c | 4308 | .release = generic_pipe_buf_release, |
34cd4998 SR |
4309 | .steal = generic_pipe_buf_steal, |
4310 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
4311 | }; |
4312 | ||
34cd4998 | 4313 | static size_t |
fa7c7f6e | 4314 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
4315 | { |
4316 | size_t count; | |
4317 | int ret; | |
4318 | ||
4319 | /* Seq buffer is page-sized, exactly what we need. */ | |
4320 | for (;;) { | |
4321 | count = iter->seq.len; | |
4322 | ret = print_trace_line(iter); | |
4323 | count = iter->seq.len - count; | |
4324 | if (rem < count) { | |
4325 | rem = 0; | |
4326 | iter->seq.len -= count; | |
4327 | break; | |
4328 | } | |
4329 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
4330 | iter->seq.len -= count; | |
4331 | break; | |
4332 | } | |
4333 | ||
74e7ff8c LJ |
4334 | if (ret != TRACE_TYPE_NO_CONSUME) |
4335 | trace_consume(iter); | |
34cd4998 | 4336 | rem -= count; |
955b61e5 | 4337 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
4338 | rem = 0; |
4339 | iter->ent = NULL; | |
4340 | break; | |
4341 | } | |
4342 | } | |
4343 | ||
4344 | return rem; | |
4345 | } | |
4346 | ||
3c56819b EGM |
4347 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
4348 | loff_t *ppos, | |
4349 | struct pipe_inode_info *pipe, | |
4350 | size_t len, | |
4351 | unsigned int flags) | |
4352 | { | |
35f3d14d JA |
4353 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
4354 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
4355 | struct trace_iterator *iter = filp->private_data; |
4356 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
4357 | .pages = pages_def, |
4358 | .partial = partial_def, | |
34cd4998 | 4359 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 4360 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
4361 | .flags = flags, |
4362 | .ops = &tracing_pipe_buf_ops, | |
4363 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 4364 | }; |
2b6080f2 | 4365 | struct trace_array *tr = iter->tr; |
3c56819b | 4366 | ssize_t ret; |
34cd4998 | 4367 | size_t rem; |
3c56819b EGM |
4368 | unsigned int i; |
4369 | ||
35f3d14d JA |
4370 | if (splice_grow_spd(pipe, &spd)) |
4371 | return -ENOMEM; | |
4372 | ||
d7350c3f | 4373 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 4374 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4375 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4376 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4377 | mutex_unlock(&trace_types_lock); |
4378 | ||
4379 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
4380 | |
4381 | if (iter->trace->splice_read) { | |
4382 | ret = iter->trace->splice_read(iter, filp, | |
4383 | ppos, pipe, len, flags); | |
4384 | if (ret) | |
34cd4998 | 4385 | goto out_err; |
3c56819b EGM |
4386 | } |
4387 | ||
4388 | ret = tracing_wait_pipe(filp); | |
4389 | if (ret <= 0) | |
34cd4998 | 4390 | goto out_err; |
3c56819b | 4391 | |
955b61e5 | 4392 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 4393 | ret = -EFAULT; |
34cd4998 | 4394 | goto out_err; |
3c56819b EGM |
4395 | } |
4396 | ||
4f535968 | 4397 | trace_event_read_lock(); |
7e53bd42 | 4398 | trace_access_lock(iter->cpu_file); |
4f535968 | 4399 | |
3c56819b | 4400 | /* Fill as many pages as possible. */ |
35f3d14d JA |
4401 | for (i = 0, rem = len; i < pipe->buffers && rem; i++) { |
4402 | spd.pages[i] = alloc_page(GFP_KERNEL); | |
4403 | if (!spd.pages[i]) | |
34cd4998 | 4404 | break; |
3c56819b | 4405 | |
fa7c7f6e | 4406 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
4407 | |
4408 | /* Copy the data into the page, so we can start over. */ | |
4409 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 4410 | page_address(spd.pages[i]), |
3c56819b EGM |
4411 | iter->seq.len); |
4412 | if (ret < 0) { | |
35f3d14d | 4413 | __free_page(spd.pages[i]); |
3c56819b EGM |
4414 | break; |
4415 | } | |
35f3d14d JA |
4416 | spd.partial[i].offset = 0; |
4417 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 4418 | |
f9520750 | 4419 | trace_seq_init(&iter->seq); |
3c56819b EGM |
4420 | } |
4421 | ||
7e53bd42 | 4422 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4423 | trace_event_read_unlock(); |
d7350c3f | 4424 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
4425 | |
4426 | spd.nr_pages = i; | |
4427 | ||
35f3d14d JA |
4428 | ret = splice_to_pipe(pipe, &spd); |
4429 | out: | |
047fe360 | 4430 | splice_shrink_spd(&spd); |
35f3d14d | 4431 | return ret; |
3c56819b | 4432 | |
34cd4998 | 4433 | out_err: |
d7350c3f | 4434 | mutex_unlock(&iter->mutex); |
35f3d14d | 4435 | goto out; |
3c56819b EGM |
4436 | } |
4437 | ||
a98a3c3f SR |
4438 | static ssize_t |
4439 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
4440 | size_t cnt, loff_t *ppos) | |
4441 | { | |
0bc392ee ON |
4442 | struct inode *inode = file_inode(filp); |
4443 | struct trace_array *tr = inode->i_private; | |
4444 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
4445 | char buf[64]; |
4446 | int r = 0; | |
4447 | ssize_t ret; | |
a98a3c3f | 4448 | |
db526ca3 | 4449 | mutex_lock(&trace_types_lock); |
438ced17 | 4450 | |
0bc392ee | 4451 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
4452 | int cpu, buf_size_same; |
4453 | unsigned long size; | |
4454 | ||
4455 | size = 0; | |
4456 | buf_size_same = 1; | |
4457 | /* check if all cpu sizes are same */ | |
4458 | for_each_tracing_cpu(cpu) { | |
4459 | /* fill in the size from first enabled cpu */ | |
4460 | if (size == 0) | |
12883efb SRRH |
4461 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
4462 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
4463 | buf_size_same = 0; |
4464 | break; | |
4465 | } | |
4466 | } | |
4467 | ||
4468 | if (buf_size_same) { | |
4469 | if (!ring_buffer_expanded) | |
4470 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
4471 | size >> 10, | |
4472 | trace_buf_size >> 10); | |
4473 | else | |
4474 | r = sprintf(buf, "%lu\n", size >> 10); | |
4475 | } else | |
4476 | r = sprintf(buf, "X\n"); | |
4477 | } else | |
0bc392ee | 4478 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10); |
438ced17 | 4479 | |
db526ca3 SR |
4480 | mutex_unlock(&trace_types_lock); |
4481 | ||
438ced17 VN |
4482 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
4483 | return ret; | |
a98a3c3f SR |
4484 | } |
4485 | ||
4486 | static ssize_t | |
4487 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
4488 | size_t cnt, loff_t *ppos) | |
4489 | { | |
0bc392ee ON |
4490 | struct inode *inode = file_inode(filp); |
4491 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 4492 | unsigned long val; |
4f271a2a | 4493 | int ret; |
a98a3c3f | 4494 | |
22fe9b54 PH |
4495 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4496 | if (ret) | |
c6caeeb1 | 4497 | return ret; |
a98a3c3f SR |
4498 | |
4499 | /* must have at least 1 entry */ | |
4500 | if (!val) | |
4501 | return -EINVAL; | |
4502 | ||
1696b2b0 SR |
4503 | /* value is in KB */ |
4504 | val <<= 10; | |
0bc392ee | 4505 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
4506 | if (ret < 0) |
4507 | return ret; | |
a98a3c3f | 4508 | |
cf8517cf | 4509 | *ppos += cnt; |
a98a3c3f | 4510 | |
4f271a2a VN |
4511 | return cnt; |
4512 | } | |
bf5e6519 | 4513 | |
f81ab074 VN |
4514 | static ssize_t |
4515 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
4516 | size_t cnt, loff_t *ppos) | |
4517 | { | |
4518 | struct trace_array *tr = filp->private_data; | |
4519 | char buf[64]; | |
4520 | int r, cpu; | |
4521 | unsigned long size = 0, expanded_size = 0; | |
4522 | ||
4523 | mutex_lock(&trace_types_lock); | |
4524 | for_each_tracing_cpu(cpu) { | |
12883efb | 4525 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
4526 | if (!ring_buffer_expanded) |
4527 | expanded_size += trace_buf_size >> 10; | |
4528 | } | |
4529 | if (ring_buffer_expanded) | |
4530 | r = sprintf(buf, "%lu\n", size); | |
4531 | else | |
4532 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
4533 | mutex_unlock(&trace_types_lock); | |
4534 | ||
4535 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4536 | } | |
4537 | ||
4f271a2a VN |
4538 | static ssize_t |
4539 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
4540 | size_t cnt, loff_t *ppos) | |
4541 | { | |
4542 | /* | |
4543 | * There is no need to read what the user has written, this function | |
4544 | * is just to make sure that there is no error when "echo" is used | |
4545 | */ | |
4546 | ||
4547 | *ppos += cnt; | |
a98a3c3f SR |
4548 | |
4549 | return cnt; | |
4550 | } | |
4551 | ||
4f271a2a VN |
4552 | static int |
4553 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
4554 | { | |
2b6080f2 SR |
4555 | struct trace_array *tr = inode->i_private; |
4556 | ||
cf30cf67 SR |
4557 | /* disable tracing ? */ |
4558 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
711e1243 | 4559 | tracer_tracing_off(tr); |
4f271a2a | 4560 | /* resize the ring buffer to 0 */ |
2b6080f2 | 4561 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 4562 | |
7b85af63 SRRH |
4563 | trace_array_put(tr); |
4564 | ||
4f271a2a VN |
4565 | return 0; |
4566 | } | |
4567 | ||
5bf9a1ee PP |
4568 | static ssize_t |
4569 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
4570 | size_t cnt, loff_t *fpos) | |
4571 | { | |
d696b58c | 4572 | unsigned long addr = (unsigned long)ubuf; |
2d71619c | 4573 | struct trace_array *tr = filp->private_data; |
d696b58c SR |
4574 | struct ring_buffer_event *event; |
4575 | struct ring_buffer *buffer; | |
4576 | struct print_entry *entry; | |
4577 | unsigned long irq_flags; | |
4578 | struct page *pages[2]; | |
6edb2a8a | 4579 | void *map_page[2]; |
d696b58c SR |
4580 | int nr_pages = 1; |
4581 | ssize_t written; | |
d696b58c SR |
4582 | int offset; |
4583 | int size; | |
4584 | int len; | |
4585 | int ret; | |
6edb2a8a | 4586 | int i; |
5bf9a1ee | 4587 | |
c76f0694 | 4588 | if (tracing_disabled) |
5bf9a1ee PP |
4589 | return -EINVAL; |
4590 | ||
5224c3a3 MSB |
4591 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
4592 | return -EINVAL; | |
4593 | ||
5bf9a1ee PP |
4594 | if (cnt > TRACE_BUF_SIZE) |
4595 | cnt = TRACE_BUF_SIZE; | |
4596 | ||
d696b58c SR |
4597 | /* |
4598 | * Userspace is injecting traces into the kernel trace buffer. | |
4599 | * We want to be as non intrusive as possible. | |
4600 | * To do so, we do not want to allocate any special buffers | |
4601 | * or take any locks, but instead write the userspace data | |
4602 | * straight into the ring buffer. | |
4603 | * | |
4604 | * First we need to pin the userspace buffer into memory, | |
4605 | * which, most likely it is, because it just referenced it. | |
4606 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
4607 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
4608 | * pages directly. We then write the data directly into the | |
4609 | * ring buffer. | |
4610 | */ | |
4611 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 4612 | |
d696b58c SR |
4613 | /* check if we cross pages */ |
4614 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
4615 | nr_pages = 2; | |
4616 | ||
4617 | offset = addr & (PAGE_SIZE - 1); | |
4618 | addr &= PAGE_MASK; | |
4619 | ||
4620 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
4621 | if (ret < nr_pages) { | |
4622 | while (--ret >= 0) | |
4623 | put_page(pages[ret]); | |
4624 | written = -EFAULT; | |
4625 | goto out; | |
5bf9a1ee | 4626 | } |
d696b58c | 4627 | |
6edb2a8a SR |
4628 | for (i = 0; i < nr_pages; i++) |
4629 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
4630 | |
4631 | local_save_flags(irq_flags); | |
4632 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
2d71619c | 4633 | buffer = tr->trace_buffer.buffer; |
d696b58c SR |
4634 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
4635 | irq_flags, preempt_count()); | |
4636 | if (!event) { | |
4637 | /* Ring buffer disabled, return as if not open for write */ | |
4638 | written = -EBADF; | |
4639 | goto out_unlock; | |
5bf9a1ee | 4640 | } |
d696b58c SR |
4641 | |
4642 | entry = ring_buffer_event_data(event); | |
4643 | entry->ip = _THIS_IP_; | |
4644 | ||
4645 | if (nr_pages == 2) { | |
4646 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
4647 | memcpy(&entry->buf, map_page[0] + offset, len); |
4648 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 4649 | } else |
6edb2a8a | 4650 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 4651 | |
d696b58c SR |
4652 | if (entry->buf[cnt - 1] != '\n') { |
4653 | entry->buf[cnt] = '\n'; | |
4654 | entry->buf[cnt + 1] = '\0'; | |
4655 | } else | |
4656 | entry->buf[cnt] = '\0'; | |
4657 | ||
7ffbd48d | 4658 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 4659 | |
d696b58c | 4660 | written = cnt; |
5bf9a1ee | 4661 | |
d696b58c | 4662 | *fpos += written; |
1aa54bca | 4663 | |
d696b58c | 4664 | out_unlock: |
6edb2a8a SR |
4665 | for (i = 0; i < nr_pages; i++){ |
4666 | kunmap_atomic(map_page[i]); | |
4667 | put_page(pages[i]); | |
4668 | } | |
d696b58c | 4669 | out: |
1aa54bca | 4670 | return written; |
5bf9a1ee PP |
4671 | } |
4672 | ||
13f16d20 | 4673 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 4674 | { |
2b6080f2 | 4675 | struct trace_array *tr = m->private; |
5079f326 Z |
4676 | int i; |
4677 | ||
4678 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 4679 | seq_printf(m, |
5079f326 | 4680 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
4681 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
4682 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 4683 | seq_putc(m, '\n'); |
5079f326 | 4684 | |
13f16d20 | 4685 | return 0; |
5079f326 Z |
4686 | } |
4687 | ||
4688 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
4689 | size_t cnt, loff_t *fpos) | |
4690 | { | |
2b6080f2 SR |
4691 | struct seq_file *m = filp->private_data; |
4692 | struct trace_array *tr = m->private; | |
5079f326 Z |
4693 | char buf[64]; |
4694 | const char *clockstr; | |
4695 | int i; | |
4696 | ||
4697 | if (cnt >= sizeof(buf)) | |
4698 | return -EINVAL; | |
4699 | ||
4700 | if (copy_from_user(&buf, ubuf, cnt)) | |
4701 | return -EFAULT; | |
4702 | ||
4703 | buf[cnt] = 0; | |
4704 | ||
4705 | clockstr = strstrip(buf); | |
4706 | ||
4707 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
4708 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
4709 | break; | |
4710 | } | |
4711 | if (i == ARRAY_SIZE(trace_clocks)) | |
4712 | return -EINVAL; | |
4713 | ||
5079f326 Z |
4714 | mutex_lock(&trace_types_lock); |
4715 | ||
2b6080f2 SR |
4716 | tr->clock_id = i; |
4717 | ||
12883efb | 4718 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 4719 | |
60303ed3 DS |
4720 | /* |
4721 | * New clock may not be consistent with the previous clock. | |
4722 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
4723 | */ | |
9457158b | 4724 | tracing_reset_online_cpus(&tr->trace_buffer); |
12883efb SRRH |
4725 | |
4726 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4727 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) | |
4728 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); | |
9457158b | 4729 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 4730 | #endif |
60303ed3 | 4731 | |
5079f326 Z |
4732 | mutex_unlock(&trace_types_lock); |
4733 | ||
4734 | *fpos += cnt; | |
4735 | ||
4736 | return cnt; | |
4737 | } | |
4738 | ||
13f16d20 LZ |
4739 | static int tracing_clock_open(struct inode *inode, struct file *file) |
4740 | { | |
7b85af63 SRRH |
4741 | struct trace_array *tr = inode->i_private; |
4742 | int ret; | |
4743 | ||
13f16d20 LZ |
4744 | if (tracing_disabled) |
4745 | return -ENODEV; | |
2b6080f2 | 4746 | |
7b85af63 SRRH |
4747 | if (trace_array_get(tr)) |
4748 | return -ENODEV; | |
4749 | ||
4750 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
4751 | if (ret < 0) | |
4752 | trace_array_put(tr); | |
4753 | ||
4754 | return ret; | |
13f16d20 LZ |
4755 | } |
4756 | ||
6de58e62 SRRH |
4757 | struct ftrace_buffer_info { |
4758 | struct trace_iterator iter; | |
4759 | void *spare; | |
4760 | unsigned int read; | |
4761 | }; | |
4762 | ||
debdd57f HT |
4763 | #ifdef CONFIG_TRACER_SNAPSHOT |
4764 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
4765 | { | |
6484c71c | 4766 | struct trace_array *tr = inode->i_private; |
debdd57f | 4767 | struct trace_iterator *iter; |
2b6080f2 | 4768 | struct seq_file *m; |
debdd57f HT |
4769 | int ret = 0; |
4770 | ||
ff451961 SRRH |
4771 | if (trace_array_get(tr) < 0) |
4772 | return -ENODEV; | |
4773 | ||
debdd57f | 4774 | if (file->f_mode & FMODE_READ) { |
6484c71c | 4775 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
4776 | if (IS_ERR(iter)) |
4777 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
4778 | } else { |
4779 | /* Writes still need the seq_file to hold the private data */ | |
f77d09a3 | 4780 | ret = -ENOMEM; |
2b6080f2 SR |
4781 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
4782 | if (!m) | |
f77d09a3 | 4783 | goto out; |
2b6080f2 SR |
4784 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
4785 | if (!iter) { | |
4786 | kfree(m); | |
f77d09a3 | 4787 | goto out; |
2b6080f2 | 4788 | } |
f77d09a3 AL |
4789 | ret = 0; |
4790 | ||
ff451961 | 4791 | iter->tr = tr; |
6484c71c ON |
4792 | iter->trace_buffer = &tr->max_buffer; |
4793 | iter->cpu_file = tracing_get_cpu(inode); | |
2b6080f2 SR |
4794 | m->private = iter; |
4795 | file->private_data = m; | |
debdd57f | 4796 | } |
f77d09a3 | 4797 | out: |
ff451961 SRRH |
4798 | if (ret < 0) |
4799 | trace_array_put(tr); | |
4800 | ||
debdd57f HT |
4801 | return ret; |
4802 | } | |
4803 | ||
4804 | static ssize_t | |
4805 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4806 | loff_t *ppos) | |
4807 | { | |
2b6080f2 SR |
4808 | struct seq_file *m = filp->private_data; |
4809 | struct trace_iterator *iter = m->private; | |
4810 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
4811 | unsigned long val; |
4812 | int ret; | |
4813 | ||
4814 | ret = tracing_update_buffers(); | |
4815 | if (ret < 0) | |
4816 | return ret; | |
4817 | ||
4818 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
4819 | if (ret) | |
4820 | return ret; | |
4821 | ||
4822 | mutex_lock(&trace_types_lock); | |
4823 | ||
2b6080f2 | 4824 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
4825 | ret = -EBUSY; |
4826 | goto out; | |
4827 | } | |
4828 | ||
4829 | switch (val) { | |
4830 | case 0: | |
f1affcaa SRRH |
4831 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
4832 | ret = -EINVAL; | |
4833 | break; | |
debdd57f | 4834 | } |
3209cff4 SRRH |
4835 | if (tr->allocated_snapshot) |
4836 | free_snapshot(tr); | |
debdd57f HT |
4837 | break; |
4838 | case 1: | |
f1affcaa SRRH |
4839 | /* Only allow per-cpu swap if the ring buffer supports it */ |
4840 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
4841 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
4842 | ret = -EINVAL; | |
4843 | break; | |
4844 | } | |
4845 | #endif | |
45ad21ca | 4846 | if (!tr->allocated_snapshot) { |
3209cff4 | 4847 | ret = alloc_snapshot(tr); |
debdd57f HT |
4848 | if (ret < 0) |
4849 | break; | |
debdd57f | 4850 | } |
debdd57f HT |
4851 | local_irq_disable(); |
4852 | /* Now, we're going to swap */ | |
f1affcaa | 4853 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 4854 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 4855 | else |
ce9bae55 | 4856 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
4857 | local_irq_enable(); |
4858 | break; | |
4859 | default: | |
45ad21ca | 4860 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
4861 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
4862 | tracing_reset_online_cpus(&tr->max_buffer); | |
4863 | else | |
4864 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
4865 | } | |
debdd57f HT |
4866 | break; |
4867 | } | |
4868 | ||
4869 | if (ret >= 0) { | |
4870 | *ppos += cnt; | |
4871 | ret = cnt; | |
4872 | } | |
4873 | out: | |
4874 | mutex_unlock(&trace_types_lock); | |
4875 | return ret; | |
4876 | } | |
2b6080f2 SR |
4877 | |
4878 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
4879 | { | |
4880 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
4881 | int ret; |
4882 | ||
4883 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
4884 | |
4885 | if (file->f_mode & FMODE_READ) | |
ff451961 | 4886 | return ret; |
2b6080f2 SR |
4887 | |
4888 | /* If write only, the seq_file is just a stub */ | |
4889 | if (m) | |
4890 | kfree(m->private); | |
4891 | kfree(m); | |
4892 | ||
4893 | return 0; | |
4894 | } | |
4895 | ||
6de58e62 SRRH |
4896 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
4897 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4898 | size_t count, loff_t *ppos); | |
4899 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
4900 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
4901 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
4902 | ||
4903 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
4904 | { | |
4905 | struct ftrace_buffer_info *info; | |
4906 | int ret; | |
4907 | ||
4908 | ret = tracing_buffers_open(inode, filp); | |
4909 | if (ret < 0) | |
4910 | return ret; | |
4911 | ||
4912 | info = filp->private_data; | |
4913 | ||
4914 | if (info->iter.trace->use_max_tr) { | |
4915 | tracing_buffers_release(inode, filp); | |
4916 | return -EBUSY; | |
4917 | } | |
4918 | ||
4919 | info->iter.snapshot = true; | |
4920 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
4921 | ||
4922 | return ret; | |
4923 | } | |
4924 | ||
debdd57f HT |
4925 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
4926 | ||
4927 | ||
5e2336a0 | 4928 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
4929 | .open = tracing_open_generic, |
4930 | .read = tracing_max_lat_read, | |
4931 | .write = tracing_max_lat_write, | |
b444786f | 4932 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4933 | }; |
4934 | ||
5e2336a0 | 4935 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
4936 | .open = tracing_open_generic, |
4937 | .read = tracing_set_trace_read, | |
4938 | .write = tracing_set_trace_write, | |
b444786f | 4939 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4940 | }; |
4941 | ||
5e2336a0 | 4942 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 4943 | .open = tracing_open_pipe, |
2a2cc8f7 | 4944 | .poll = tracing_poll_pipe, |
4bf39a94 | 4945 | .read = tracing_read_pipe, |
3c56819b | 4946 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 4947 | .release = tracing_release_pipe, |
b444786f | 4948 | .llseek = no_llseek, |
b3806b43 SR |
4949 | }; |
4950 | ||
5e2336a0 | 4951 | static const struct file_operations tracing_entries_fops = { |
0bc392ee | 4952 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
4953 | .read = tracing_entries_read, |
4954 | .write = tracing_entries_write, | |
b444786f | 4955 | .llseek = generic_file_llseek, |
0bc392ee | 4956 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
4957 | }; |
4958 | ||
f81ab074 | 4959 | static const struct file_operations tracing_total_entries_fops = { |
7b85af63 | 4960 | .open = tracing_open_generic_tr, |
f81ab074 VN |
4961 | .read = tracing_total_entries_read, |
4962 | .llseek = generic_file_llseek, | |
7b85af63 | 4963 | .release = tracing_release_generic_tr, |
f81ab074 VN |
4964 | }; |
4965 | ||
4f271a2a | 4966 | static const struct file_operations tracing_free_buffer_fops = { |
7b85af63 | 4967 | .open = tracing_open_generic_tr, |
4f271a2a VN |
4968 | .write = tracing_free_buffer_write, |
4969 | .release = tracing_free_buffer_release, | |
4970 | }; | |
4971 | ||
5e2336a0 | 4972 | static const struct file_operations tracing_mark_fops = { |
7b85af63 | 4973 | .open = tracing_open_generic_tr, |
5bf9a1ee | 4974 | .write = tracing_mark_write, |
b444786f | 4975 | .llseek = generic_file_llseek, |
7b85af63 | 4976 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
4977 | }; |
4978 | ||
5079f326 | 4979 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
4980 | .open = tracing_clock_open, |
4981 | .read = seq_read, | |
4982 | .llseek = seq_lseek, | |
7b85af63 | 4983 | .release = tracing_single_release_tr, |
5079f326 Z |
4984 | .write = tracing_clock_write, |
4985 | }; | |
4986 | ||
debdd57f HT |
4987 | #ifdef CONFIG_TRACER_SNAPSHOT |
4988 | static const struct file_operations snapshot_fops = { | |
4989 | .open = tracing_snapshot_open, | |
4990 | .read = seq_read, | |
4991 | .write = tracing_snapshot_write, | |
098c879e | 4992 | .llseek = tracing_lseek, |
2b6080f2 | 4993 | .release = tracing_snapshot_release, |
debdd57f | 4994 | }; |
debdd57f | 4995 | |
6de58e62 SRRH |
4996 | static const struct file_operations snapshot_raw_fops = { |
4997 | .open = snapshot_raw_open, | |
4998 | .read = tracing_buffers_read, | |
4999 | .release = tracing_buffers_release, | |
5000 | .splice_read = tracing_buffers_splice_read, | |
5001 | .llseek = no_llseek, | |
2cadf913 SR |
5002 | }; |
5003 | ||
6de58e62 SRRH |
5004 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5005 | ||
2cadf913 SR |
5006 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
5007 | { | |
46ef2be0 | 5008 | struct trace_array *tr = inode->i_private; |
2cadf913 | 5009 | struct ftrace_buffer_info *info; |
7b85af63 | 5010 | int ret; |
2cadf913 SR |
5011 | |
5012 | if (tracing_disabled) | |
5013 | return -ENODEV; | |
5014 | ||
7b85af63 SRRH |
5015 | if (trace_array_get(tr) < 0) |
5016 | return -ENODEV; | |
5017 | ||
2cadf913 | 5018 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
7b85af63 SRRH |
5019 | if (!info) { |
5020 | trace_array_put(tr); | |
2cadf913 | 5021 | return -ENOMEM; |
7b85af63 | 5022 | } |
2cadf913 | 5023 | |
a695cb58 SRRH |
5024 | mutex_lock(&trace_types_lock); |
5025 | ||
cc60cdc9 | 5026 | info->iter.tr = tr; |
46ef2be0 | 5027 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 5028 | info->iter.trace = tr->current_trace; |
12883efb | 5029 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 5030 | info->spare = NULL; |
2cadf913 | 5031 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 5032 | info->read = (unsigned int)-1; |
2cadf913 SR |
5033 | |
5034 | filp->private_data = info; | |
5035 | ||
a695cb58 SRRH |
5036 | mutex_unlock(&trace_types_lock); |
5037 | ||
7b85af63 SRRH |
5038 | ret = nonseekable_open(inode, filp); |
5039 | if (ret < 0) | |
5040 | trace_array_put(tr); | |
5041 | ||
5042 | return ret; | |
2cadf913 SR |
5043 | } |
5044 | ||
cc60cdc9 SR |
5045 | static unsigned int |
5046 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
5047 | { | |
5048 | struct ftrace_buffer_info *info = filp->private_data; | |
5049 | struct trace_iterator *iter = &info->iter; | |
5050 | ||
5051 | return trace_poll(iter, filp, poll_table); | |
5052 | } | |
5053 | ||
2cadf913 SR |
5054 | static ssize_t |
5055 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5056 | size_t count, loff_t *ppos) | |
5057 | { | |
5058 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 5059 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5060 | ssize_t ret; |
6de58e62 | 5061 | ssize_t size; |
2cadf913 | 5062 | |
2dc5d12b SR |
5063 | if (!count) |
5064 | return 0; | |
5065 | ||
6de58e62 SRRH |
5066 | mutex_lock(&trace_types_lock); |
5067 | ||
5068 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5069 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
5070 | size = -EBUSY; | |
5071 | goto out_unlock; | |
5072 | } | |
5073 | #endif | |
5074 | ||
ddd538f3 | 5075 | if (!info->spare) |
12883efb SRRH |
5076 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
5077 | iter->cpu_file); | |
6de58e62 | 5078 | size = -ENOMEM; |
ddd538f3 | 5079 | if (!info->spare) |
6de58e62 | 5080 | goto out_unlock; |
ddd538f3 | 5081 | |
2cadf913 SR |
5082 | /* Do we have previous read data to read? */ |
5083 | if (info->read < PAGE_SIZE) | |
5084 | goto read; | |
5085 | ||
b627344f | 5086 | again: |
cc60cdc9 | 5087 | trace_access_lock(iter->cpu_file); |
12883efb | 5088 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
5089 | &info->spare, |
5090 | count, | |
cc60cdc9 SR |
5091 | iter->cpu_file, 0); |
5092 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 5093 | |
b627344f SR |
5094 | if (ret < 0) { |
5095 | if (trace_empty(iter)) { | |
6de58e62 SRRH |
5096 | if ((filp->f_flags & O_NONBLOCK)) { |
5097 | size = -EAGAIN; | |
5098 | goto out_unlock; | |
5099 | } | |
5100 | mutex_unlock(&trace_types_lock); | |
b627344f | 5101 | iter->trace->wait_pipe(iter); |
6de58e62 SRRH |
5102 | mutex_lock(&trace_types_lock); |
5103 | if (signal_pending(current)) { | |
5104 | size = -EINTR; | |
5105 | goto out_unlock; | |
5106 | } | |
b627344f SR |
5107 | goto again; |
5108 | } | |
6de58e62 SRRH |
5109 | size = 0; |
5110 | goto out_unlock; | |
b627344f | 5111 | } |
436fc280 | 5112 | |
436fc280 | 5113 | info->read = 0; |
b627344f | 5114 | read: |
2cadf913 SR |
5115 | size = PAGE_SIZE - info->read; |
5116 | if (size > count) | |
5117 | size = count; | |
5118 | ||
5119 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
6de58e62 SRRH |
5120 | if (ret == size) { |
5121 | size = -EFAULT; | |
5122 | goto out_unlock; | |
5123 | } | |
2dc5d12b SR |
5124 | size -= ret; |
5125 | ||
2cadf913 SR |
5126 | *ppos += size; |
5127 | info->read += size; | |
5128 | ||
6de58e62 SRRH |
5129 | out_unlock: |
5130 | mutex_unlock(&trace_types_lock); | |
5131 | ||
2cadf913 SR |
5132 | return size; |
5133 | } | |
5134 | ||
5135 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
5136 | { | |
5137 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5138 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5139 | |
a695cb58 SRRH |
5140 | mutex_lock(&trace_types_lock); |
5141 | ||
ff451961 | 5142 | __trace_array_put(iter->tr); |
2cadf913 | 5143 | |
ddd538f3 | 5144 | if (info->spare) |
12883efb | 5145 | ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); |
2cadf913 SR |
5146 | kfree(info); |
5147 | ||
a695cb58 SRRH |
5148 | mutex_unlock(&trace_types_lock); |
5149 | ||
2cadf913 SR |
5150 | return 0; |
5151 | } | |
5152 | ||
5153 | struct buffer_ref { | |
5154 | struct ring_buffer *buffer; | |
5155 | void *page; | |
5156 | int ref; | |
5157 | }; | |
5158 | ||
5159 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
5160 | struct pipe_buffer *buf) | |
5161 | { | |
5162 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5163 | ||
5164 | if (--ref->ref) | |
5165 | return; | |
5166 | ||
5167 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5168 | kfree(ref); | |
5169 | buf->private = 0; | |
5170 | } | |
5171 | ||
2cadf913 SR |
5172 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
5173 | struct pipe_buffer *buf) | |
5174 | { | |
5175 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5176 | ||
5177 | ref->ref++; | |
5178 | } | |
5179 | ||
5180 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 5181 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
5182 | .can_merge = 0, |
5183 | .map = generic_pipe_buf_map, | |
5184 | .unmap = generic_pipe_buf_unmap, | |
5185 | .confirm = generic_pipe_buf_confirm, | |
5186 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 5187 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
5188 | .get = buffer_pipe_buf_get, |
5189 | }; | |
5190 | ||
5191 | /* | |
5192 | * Callback from splice_to_pipe(), if we need to release some pages | |
5193 | * at the end of the spd in case we error'ed out in filling the pipe. | |
5194 | */ | |
5195 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
5196 | { | |
5197 | struct buffer_ref *ref = | |
5198 | (struct buffer_ref *)spd->partial[i].private; | |
5199 | ||
5200 | if (--ref->ref) | |
5201 | return; | |
5202 | ||
5203 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5204 | kfree(ref); | |
5205 | spd->partial[i].private = 0; | |
5206 | } | |
5207 | ||
5208 | static ssize_t | |
5209 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5210 | struct pipe_inode_info *pipe, size_t len, | |
5211 | unsigned int flags) | |
5212 | { | |
5213 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5214 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
5215 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
5216 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 5217 | struct splice_pipe_desc spd = { |
35f3d14d JA |
5218 | .pages = pages_def, |
5219 | .partial = partial_def, | |
047fe360 | 5220 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
5221 | .flags = flags, |
5222 | .ops = &buffer_pipe_buf_ops, | |
5223 | .spd_release = buffer_spd_release, | |
5224 | }; | |
5225 | struct buffer_ref *ref; | |
93459c6c | 5226 | int entries, size, i; |
6de58e62 | 5227 | ssize_t ret; |
2cadf913 | 5228 | |
6de58e62 SRRH |
5229 | mutex_lock(&trace_types_lock); |
5230 | ||
5231 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5232 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
5233 | ret = -EBUSY; | |
5234 | goto out; | |
5235 | } | |
5236 | #endif | |
5237 | ||
5238 | if (splice_grow_spd(pipe, &spd)) { | |
5239 | ret = -ENOMEM; | |
5240 | goto out; | |
5241 | } | |
35f3d14d | 5242 | |
93cfb3c9 | 5243 | if (*ppos & (PAGE_SIZE - 1)) { |
35f3d14d JA |
5244 | ret = -EINVAL; |
5245 | goto out; | |
93cfb3c9 LJ |
5246 | } |
5247 | ||
5248 | if (len & (PAGE_SIZE - 1)) { | |
35f3d14d JA |
5249 | if (len < PAGE_SIZE) { |
5250 | ret = -EINVAL; | |
5251 | goto out; | |
5252 | } | |
93cfb3c9 LJ |
5253 | len &= PAGE_MASK; |
5254 | } | |
5255 | ||
cc60cdc9 SR |
5256 | again: |
5257 | trace_access_lock(iter->cpu_file); | |
12883efb | 5258 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 5259 | |
35f3d14d | 5260 | for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
5261 | struct page *page; |
5262 | int r; | |
5263 | ||
5264 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
5265 | if (!ref) | |
5266 | break; | |
5267 | ||
7267fa68 | 5268 | ref->ref = 1; |
12883efb | 5269 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 5270 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
2cadf913 SR |
5271 | if (!ref->page) { |
5272 | kfree(ref); | |
5273 | break; | |
5274 | } | |
5275 | ||
5276 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 5277 | len, iter->cpu_file, 1); |
2cadf913 | 5278 | if (r < 0) { |
7ea59064 | 5279 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
5280 | kfree(ref); |
5281 | break; | |
5282 | } | |
5283 | ||
5284 | /* | |
5285 | * zero out any left over data, this is going to | |
5286 | * user land. | |
5287 | */ | |
5288 | size = ring_buffer_page_len(ref->page); | |
5289 | if (size < PAGE_SIZE) | |
5290 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
5291 | ||
5292 | page = virt_to_page(ref->page); | |
5293 | ||
5294 | spd.pages[i] = page; | |
5295 | spd.partial[i].len = PAGE_SIZE; | |
5296 | spd.partial[i].offset = 0; | |
5297 | spd.partial[i].private = (unsigned long)ref; | |
5298 | spd.nr_pages++; | |
93cfb3c9 | 5299 | *ppos += PAGE_SIZE; |
93459c6c | 5300 | |
12883efb | 5301 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
5302 | } |
5303 | ||
cc60cdc9 | 5304 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
5305 | spd.nr_pages = i; |
5306 | ||
5307 | /* did we read anything? */ | |
5308 | if (!spd.nr_pages) { | |
cc60cdc9 | 5309 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) { |
2cadf913 | 5310 | ret = -EAGAIN; |
cc60cdc9 SR |
5311 | goto out; |
5312 | } | |
6de58e62 | 5313 | mutex_unlock(&trace_types_lock); |
b627344f | 5314 | iter->trace->wait_pipe(iter); |
6de58e62 | 5315 | mutex_lock(&trace_types_lock); |
cc60cdc9 SR |
5316 | if (signal_pending(current)) { |
5317 | ret = -EINTR; | |
5318 | goto out; | |
5319 | } | |
5320 | goto again; | |
2cadf913 SR |
5321 | } |
5322 | ||
5323 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 5324 | splice_shrink_spd(&spd); |
35f3d14d | 5325 | out: |
6de58e62 SRRH |
5326 | mutex_unlock(&trace_types_lock); |
5327 | ||
2cadf913 SR |
5328 | return ret; |
5329 | } | |
5330 | ||
5331 | static const struct file_operations tracing_buffers_fops = { | |
5332 | .open = tracing_buffers_open, | |
5333 | .read = tracing_buffers_read, | |
cc60cdc9 | 5334 | .poll = tracing_buffers_poll, |
2cadf913 SR |
5335 | .release = tracing_buffers_release, |
5336 | .splice_read = tracing_buffers_splice_read, | |
5337 | .llseek = no_llseek, | |
5338 | }; | |
5339 | ||
c8d77183 SR |
5340 | static ssize_t |
5341 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
5342 | size_t count, loff_t *ppos) | |
5343 | { | |
4d3435b8 ON |
5344 | struct inode *inode = file_inode(filp); |
5345 | struct trace_array *tr = inode->i_private; | |
12883efb | 5346 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
4d3435b8 | 5347 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
5348 | struct trace_seq *s; |
5349 | unsigned long cnt; | |
c64e148a VN |
5350 | unsigned long long t; |
5351 | unsigned long usec_rem; | |
c8d77183 | 5352 | |
e4f2d10f | 5353 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 5354 | if (!s) |
a646365c | 5355 | return -ENOMEM; |
c8d77183 SR |
5356 | |
5357 | trace_seq_init(s); | |
5358 | ||
12883efb | 5359 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5360 | trace_seq_printf(s, "entries: %ld\n", cnt); |
5361 | ||
12883efb | 5362 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5363 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
5364 | ||
12883efb | 5365 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5366 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
5367 | ||
12883efb | 5368 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
5369 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
5370 | ||
58e8eedf | 5371 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 5372 | /* local or global for trace_clock */ |
12883efb | 5373 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
5374 | usec_rem = do_div(t, USEC_PER_SEC); |
5375 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
5376 | t, usec_rem); | |
5377 | ||
12883efb | 5378 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
5379 | usec_rem = do_div(t, USEC_PER_SEC); |
5380 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
5381 | } else { | |
5382 | /* counter or tsc mode for trace_clock */ | |
5383 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 5384 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 5385 | |
11043d8b | 5386 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 5387 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 5388 | } |
c64e148a | 5389 | |
12883efb | 5390 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
5391 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
5392 | ||
12883efb | 5393 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
5394 | trace_seq_printf(s, "read events: %ld\n", cnt); |
5395 | ||
c8d77183 SR |
5396 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
5397 | ||
5398 | kfree(s); | |
5399 | ||
5400 | return count; | |
5401 | } | |
5402 | ||
5403 | static const struct file_operations tracing_stats_fops = { | |
4d3435b8 | 5404 | .open = tracing_open_generic_tr, |
c8d77183 | 5405 | .read = tracing_stats_read, |
b444786f | 5406 | .llseek = generic_file_llseek, |
4d3435b8 | 5407 | .release = tracing_release_generic_tr, |
c8d77183 SR |
5408 | }; |
5409 | ||
bc0c38d1 SR |
5410 | #ifdef CONFIG_DYNAMIC_FTRACE |
5411 | ||
b807c3d0 SR |
5412 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
5413 | { | |
5414 | return 0; | |
5415 | } | |
5416 | ||
bc0c38d1 | 5417 | static ssize_t |
b807c3d0 | 5418 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
5419 | size_t cnt, loff_t *ppos) |
5420 | { | |
a26a2a27 SR |
5421 | static char ftrace_dyn_info_buffer[1024]; |
5422 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 5423 | unsigned long *p = filp->private_data; |
b807c3d0 | 5424 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 5425 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
5426 | int r; |
5427 | ||
b807c3d0 SR |
5428 | mutex_lock(&dyn_info_mutex); |
5429 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 5430 | |
a26a2a27 | 5431 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
5432 | buf[r++] = '\n'; |
5433 | ||
5434 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5435 | ||
5436 | mutex_unlock(&dyn_info_mutex); | |
5437 | ||
5438 | return r; | |
bc0c38d1 SR |
5439 | } |
5440 | ||
5e2336a0 | 5441 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 5442 | .open = tracing_open_generic, |
b807c3d0 | 5443 | .read = tracing_read_dyn_info, |
b444786f | 5444 | .llseek = generic_file_llseek, |
bc0c38d1 | 5445 | }; |
77fd5c15 | 5446 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 5447 | |
77fd5c15 SRRH |
5448 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
5449 | static void | |
5450 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
5451 | { | |
5452 | tracing_snapshot(); | |
5453 | } | |
bc0c38d1 | 5454 | |
77fd5c15 SRRH |
5455 | static void |
5456 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
bc0c38d1 | 5457 | { |
77fd5c15 SRRH |
5458 | unsigned long *count = (long *)data; |
5459 | ||
5460 | if (!*count) | |
5461 | return; | |
bc0c38d1 | 5462 | |
77fd5c15 SRRH |
5463 | if (*count != -1) |
5464 | (*count)--; | |
5465 | ||
5466 | tracing_snapshot(); | |
5467 | } | |
5468 | ||
5469 | static int | |
5470 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
5471 | struct ftrace_probe_ops *ops, void *data) | |
5472 | { | |
5473 | long count = (long)data; | |
5474 | ||
5475 | seq_printf(m, "%ps:", (void *)ip); | |
5476 | ||
5477 | seq_printf(m, "snapshot"); | |
5478 | ||
5479 | if (count == -1) | |
5480 | seq_printf(m, ":unlimited\n"); | |
5481 | else | |
5482 | seq_printf(m, ":count=%ld\n", count); | |
5483 | ||
5484 | return 0; | |
5485 | } | |
5486 | ||
5487 | static struct ftrace_probe_ops snapshot_probe_ops = { | |
5488 | .func = ftrace_snapshot, | |
5489 | .print = ftrace_snapshot_print, | |
5490 | }; | |
5491 | ||
5492 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
5493 | .func = ftrace_count_snapshot, | |
5494 | .print = ftrace_snapshot_print, | |
5495 | }; | |
5496 | ||
5497 | static int | |
5498 | ftrace_trace_snapshot_callback(struct ftrace_hash *hash, | |
5499 | char *glob, char *cmd, char *param, int enable) | |
5500 | { | |
5501 | struct ftrace_probe_ops *ops; | |
5502 | void *count = (void *)-1; | |
5503 | char *number; | |
5504 | int ret; | |
5505 | ||
5506 | /* hash funcs only work with set_ftrace_filter */ | |
5507 | if (!enable) | |
5508 | return -EINVAL; | |
5509 | ||
5510 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
5511 | ||
5512 | if (glob[0] == '!') { | |
5513 | unregister_ftrace_function_probe_func(glob+1, ops); | |
5514 | return 0; | |
5515 | } | |
5516 | ||
5517 | if (!param) | |
5518 | goto out_reg; | |
5519 | ||
5520 | number = strsep(¶m, ":"); | |
5521 | ||
5522 | if (!strlen(number)) | |
5523 | goto out_reg; | |
5524 | ||
5525 | /* | |
5526 | * We use the callback data field (which is a pointer) | |
5527 | * as our counter. | |
5528 | */ | |
5529 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
5530 | if (ret) | |
5531 | return ret; | |
5532 | ||
5533 | out_reg: | |
5534 | ret = register_ftrace_function_probe(glob, ops, count); | |
5535 | ||
5536 | if (ret >= 0) | |
5537 | alloc_snapshot(&global_trace); | |
5538 | ||
5539 | return ret < 0 ? ret : 0; | |
5540 | } | |
5541 | ||
5542 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
5543 | .name = "snapshot", | |
5544 | .func = ftrace_trace_snapshot_callback, | |
5545 | }; | |
5546 | ||
38de93ab | 5547 | static __init int register_snapshot_cmd(void) |
77fd5c15 SRRH |
5548 | { |
5549 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
5550 | } | |
5551 | #else | |
38de93ab | 5552 | static inline __init int register_snapshot_cmd(void) { return 0; } |
77fd5c15 | 5553 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ |
bc0c38d1 | 5554 | |
2b6080f2 | 5555 | struct dentry *tracing_init_dentry_tr(struct trace_array *tr) |
bc0c38d1 | 5556 | { |
2b6080f2 SR |
5557 | if (tr->dir) |
5558 | return tr->dir; | |
bc0c38d1 | 5559 | |
3e1f60b8 FW |
5560 | if (!debugfs_initialized()) |
5561 | return NULL; | |
5562 | ||
2b6080f2 SR |
5563 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) |
5564 | tr->dir = debugfs_create_dir("tracing", NULL); | |
bc0c38d1 | 5565 | |
687c878a J |
5566 | if (!tr->dir) |
5567 | pr_warn_once("Could not create debugfs directory 'tracing'\n"); | |
bc0c38d1 | 5568 | |
2b6080f2 | 5569 | return tr->dir; |
bc0c38d1 SR |
5570 | } |
5571 | ||
2b6080f2 SR |
5572 | struct dentry *tracing_init_dentry(void) |
5573 | { | |
5574 | return tracing_init_dentry_tr(&global_trace); | |
5575 | } | |
b04cc6b1 | 5576 | |
2b6080f2 | 5577 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 5578 | { |
b04cc6b1 FW |
5579 | struct dentry *d_tracer; |
5580 | ||
2b6080f2 SR |
5581 | if (tr->percpu_dir) |
5582 | return tr->percpu_dir; | |
b04cc6b1 | 5583 | |
2b6080f2 | 5584 | d_tracer = tracing_init_dentry_tr(tr); |
b04cc6b1 FW |
5585 | if (!d_tracer) |
5586 | return NULL; | |
5587 | ||
2b6080f2 | 5588 | tr->percpu_dir = debugfs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 5589 | |
2b6080f2 SR |
5590 | WARN_ONCE(!tr->percpu_dir, |
5591 | "Could not create debugfs directory 'per_cpu/%d'\n", cpu); | |
b04cc6b1 | 5592 | |
2b6080f2 | 5593 | return tr->percpu_dir; |
b04cc6b1 FW |
5594 | } |
5595 | ||
649e9c70 ON |
5596 | static struct dentry * |
5597 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
5598 | void *data, long cpu, const struct file_operations *fops) | |
5599 | { | |
5600 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
5601 | ||
5602 | if (ret) /* See tracing_get_cpu() */ | |
5603 | ret->d_inode->i_cdev = (void *)(cpu + 1); | |
5604 | return ret; | |
5605 | } | |
5606 | ||
2b6080f2 SR |
5607 | static void |
5608 | tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) | |
b04cc6b1 | 5609 | { |
2b6080f2 | 5610 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 5611 | struct dentry *d_cpu; |
dd49a38c | 5612 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 5613 | |
0a3d7ce7 NK |
5614 | if (!d_percpu) |
5615 | return; | |
5616 | ||
dd49a38c | 5617 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
5618 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
5619 | if (!d_cpu) { | |
5620 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
5621 | return; | |
5622 | } | |
b04cc6b1 | 5623 | |
8656e7a2 | 5624 | /* per cpu trace_pipe */ |
649e9c70 | 5625 | trace_create_cpu_file("trace_pipe", 0444, d_cpu, |
15544209 | 5626 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
5627 | |
5628 | /* per cpu trace */ | |
649e9c70 | 5629 | trace_create_cpu_file("trace", 0644, d_cpu, |
6484c71c | 5630 | tr, cpu, &tracing_fops); |
7f96f93f | 5631 | |
649e9c70 | 5632 | trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, |
46ef2be0 | 5633 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 5634 | |
649e9c70 | 5635 | trace_create_cpu_file("stats", 0444, d_cpu, |
4d3435b8 | 5636 | tr, cpu, &tracing_stats_fops); |
438ced17 | 5637 | |
649e9c70 | 5638 | trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, |
0bc392ee | 5639 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
5640 | |
5641 | #ifdef CONFIG_TRACER_SNAPSHOT | |
649e9c70 | 5642 | trace_create_cpu_file("snapshot", 0644, d_cpu, |
6484c71c | 5643 | tr, cpu, &snapshot_fops); |
6de58e62 | 5644 | |
649e9c70 | 5645 | trace_create_cpu_file("snapshot_raw", 0444, d_cpu, |
46ef2be0 | 5646 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 5647 | #endif |
b04cc6b1 FW |
5648 | } |
5649 | ||
60a11774 SR |
5650 | #ifdef CONFIG_FTRACE_SELFTEST |
5651 | /* Let selftest have access to static functions in this file */ | |
5652 | #include "trace_selftest.c" | |
5653 | #endif | |
5654 | ||
577b785f SR |
5655 | struct trace_option_dentry { |
5656 | struct tracer_opt *opt; | |
5657 | struct tracer_flags *flags; | |
2b6080f2 | 5658 | struct trace_array *tr; |
577b785f SR |
5659 | struct dentry *entry; |
5660 | }; | |
5661 | ||
5662 | static ssize_t | |
5663 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5664 | loff_t *ppos) | |
5665 | { | |
5666 | struct trace_option_dentry *topt = filp->private_data; | |
5667 | char *buf; | |
5668 | ||
5669 | if (topt->flags->val & topt->opt->bit) | |
5670 | buf = "1\n"; | |
5671 | else | |
5672 | buf = "0\n"; | |
5673 | ||
5674 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5675 | } | |
5676 | ||
5677 | static ssize_t | |
5678 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5679 | loff_t *ppos) | |
5680 | { | |
5681 | struct trace_option_dentry *topt = filp->private_data; | |
5682 | unsigned long val; | |
577b785f SR |
5683 | int ret; |
5684 | ||
22fe9b54 PH |
5685 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5686 | if (ret) | |
577b785f SR |
5687 | return ret; |
5688 | ||
8d18eaaf LZ |
5689 | if (val != 0 && val != 1) |
5690 | return -EINVAL; | |
577b785f | 5691 | |
8d18eaaf | 5692 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 5693 | mutex_lock(&trace_types_lock); |
8c1a49ae | 5694 | ret = __set_tracer_option(topt->tr, topt->flags, |
c757bea9 | 5695 | topt->opt, !val); |
577b785f SR |
5696 | mutex_unlock(&trace_types_lock); |
5697 | if (ret) | |
5698 | return ret; | |
577b785f SR |
5699 | } |
5700 | ||
5701 | *ppos += cnt; | |
5702 | ||
5703 | return cnt; | |
5704 | } | |
5705 | ||
5706 | ||
5707 | static const struct file_operations trace_options_fops = { | |
5708 | .open = tracing_open_generic, | |
5709 | .read = trace_options_read, | |
5710 | .write = trace_options_write, | |
b444786f | 5711 | .llseek = generic_file_llseek, |
577b785f SR |
5712 | }; |
5713 | ||
a8259075 SR |
5714 | static ssize_t |
5715 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5716 | loff_t *ppos) | |
5717 | { | |
5718 | long index = (long)filp->private_data; | |
5719 | char *buf; | |
5720 | ||
5721 | if (trace_flags & (1 << index)) | |
5722 | buf = "1\n"; | |
5723 | else | |
5724 | buf = "0\n"; | |
5725 | ||
5726 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5727 | } | |
5728 | ||
5729 | static ssize_t | |
5730 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5731 | loff_t *ppos) | |
5732 | { | |
2b6080f2 | 5733 | struct trace_array *tr = &global_trace; |
a8259075 | 5734 | long index = (long)filp->private_data; |
a8259075 SR |
5735 | unsigned long val; |
5736 | int ret; | |
5737 | ||
22fe9b54 PH |
5738 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5739 | if (ret) | |
a8259075 SR |
5740 | return ret; |
5741 | ||
f2d84b65 | 5742 | if (val != 0 && val != 1) |
a8259075 | 5743 | return -EINVAL; |
69d34da2 SRRH |
5744 | |
5745 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 5746 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 5747 | mutex_unlock(&trace_types_lock); |
a8259075 | 5748 | |
613f04a0 SRRH |
5749 | if (ret < 0) |
5750 | return ret; | |
5751 | ||
a8259075 SR |
5752 | *ppos += cnt; |
5753 | ||
5754 | return cnt; | |
5755 | } | |
5756 | ||
a8259075 SR |
5757 | static const struct file_operations trace_options_core_fops = { |
5758 | .open = tracing_open_generic, | |
5759 | .read = trace_options_core_read, | |
5760 | .write = trace_options_core_write, | |
b444786f | 5761 | .llseek = generic_file_llseek, |
a8259075 SR |
5762 | }; |
5763 | ||
5452af66 | 5764 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 5765 | umode_t mode, |
5452af66 FW |
5766 | struct dentry *parent, |
5767 | void *data, | |
5768 | const struct file_operations *fops) | |
5769 | { | |
5770 | struct dentry *ret; | |
5771 | ||
5772 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
5773 | if (!ret) | |
5774 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
5775 | ||
5776 | return ret; | |
5777 | } | |
5778 | ||
5779 | ||
2b6080f2 | 5780 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
5781 | { |
5782 | struct dentry *d_tracer; | |
a8259075 | 5783 | |
2b6080f2 SR |
5784 | if (tr->options) |
5785 | return tr->options; | |
a8259075 | 5786 | |
2b6080f2 | 5787 | d_tracer = tracing_init_dentry_tr(tr); |
a8259075 SR |
5788 | if (!d_tracer) |
5789 | return NULL; | |
5790 | ||
2b6080f2 SR |
5791 | tr->options = debugfs_create_dir("options", d_tracer); |
5792 | if (!tr->options) { | |
a8259075 SR |
5793 | pr_warning("Could not create debugfs directory 'options'\n"); |
5794 | return NULL; | |
5795 | } | |
5796 | ||
2b6080f2 | 5797 | return tr->options; |
a8259075 SR |
5798 | } |
5799 | ||
577b785f | 5800 | static void |
2b6080f2 SR |
5801 | create_trace_option_file(struct trace_array *tr, |
5802 | struct trace_option_dentry *topt, | |
577b785f SR |
5803 | struct tracer_flags *flags, |
5804 | struct tracer_opt *opt) | |
5805 | { | |
5806 | struct dentry *t_options; | |
577b785f | 5807 | |
2b6080f2 | 5808 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
5809 | if (!t_options) |
5810 | return; | |
5811 | ||
5812 | topt->flags = flags; | |
5813 | topt->opt = opt; | |
2b6080f2 | 5814 | topt->tr = tr; |
577b785f | 5815 | |
5452af66 | 5816 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
5817 | &trace_options_fops); |
5818 | ||
577b785f SR |
5819 | } |
5820 | ||
5821 | static struct trace_option_dentry * | |
2b6080f2 | 5822 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
5823 | { |
5824 | struct trace_option_dentry *topts; | |
5825 | struct tracer_flags *flags; | |
5826 | struct tracer_opt *opts; | |
5827 | int cnt; | |
5828 | ||
5829 | if (!tracer) | |
5830 | return NULL; | |
5831 | ||
5832 | flags = tracer->flags; | |
5833 | ||
5834 | if (!flags || !flags->opts) | |
5835 | return NULL; | |
5836 | ||
5837 | opts = flags->opts; | |
5838 | ||
5839 | for (cnt = 0; opts[cnt].name; cnt++) | |
5840 | ; | |
5841 | ||
0cfe8245 | 5842 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
5843 | if (!topts) |
5844 | return NULL; | |
5845 | ||
5846 | for (cnt = 0; opts[cnt].name; cnt++) | |
2b6080f2 | 5847 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f SR |
5848 | &opts[cnt]); |
5849 | ||
5850 | return topts; | |
5851 | } | |
5852 | ||
5853 | static void | |
5854 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
5855 | { | |
5856 | int cnt; | |
5857 | ||
5858 | if (!topts) | |
5859 | return; | |
5860 | ||
5861 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
5862 | if (topts[cnt].entry) | |
5863 | debugfs_remove(topts[cnt].entry); | |
5864 | } | |
5865 | ||
5866 | kfree(topts); | |
5867 | } | |
5868 | ||
a8259075 | 5869 | static struct dentry * |
2b6080f2 SR |
5870 | create_trace_option_core_file(struct trace_array *tr, |
5871 | const char *option, long index) | |
a8259075 SR |
5872 | { |
5873 | struct dentry *t_options; | |
a8259075 | 5874 | |
2b6080f2 | 5875 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5876 | if (!t_options) |
5877 | return NULL; | |
5878 | ||
5452af66 | 5879 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 5880 | &trace_options_core_fops); |
a8259075 SR |
5881 | } |
5882 | ||
2b6080f2 | 5883 | static __init void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
5884 | { |
5885 | struct dentry *t_options; | |
a8259075 SR |
5886 | int i; |
5887 | ||
2b6080f2 | 5888 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5889 | if (!t_options) |
5890 | return; | |
5891 | ||
5452af66 | 5892 | for (i = 0; trace_options[i]; i++) |
2b6080f2 | 5893 | create_trace_option_core_file(tr, trace_options[i], i); |
a8259075 SR |
5894 | } |
5895 | ||
499e5470 SR |
5896 | static ssize_t |
5897 | rb_simple_read(struct file *filp, char __user *ubuf, | |
5898 | size_t cnt, loff_t *ppos) | |
5899 | { | |
348f0fc2 | 5900 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
5901 | char buf[64]; |
5902 | int r; | |
5903 | ||
10246fa3 | 5904 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
5905 | r = sprintf(buf, "%d\n", r); |
5906 | ||
5907 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5908 | } | |
5909 | ||
5910 | static ssize_t | |
5911 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
5912 | size_t cnt, loff_t *ppos) | |
5913 | { | |
348f0fc2 | 5914 | struct trace_array *tr = filp->private_data; |
12883efb | 5915 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
5916 | unsigned long val; |
5917 | int ret; | |
5918 | ||
5919 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5920 | if (ret) | |
5921 | return ret; | |
5922 | ||
5923 | if (buffer) { | |
2df8f8a6 SR |
5924 | mutex_lock(&trace_types_lock); |
5925 | if (val) { | |
10246fa3 | 5926 | tracer_tracing_on(tr); |
2b6080f2 SR |
5927 | if (tr->current_trace->start) |
5928 | tr->current_trace->start(tr); | |
2df8f8a6 | 5929 | } else { |
10246fa3 | 5930 | tracer_tracing_off(tr); |
2b6080f2 SR |
5931 | if (tr->current_trace->stop) |
5932 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
5933 | } |
5934 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
5935 | } |
5936 | ||
5937 | (*ppos)++; | |
5938 | ||
5939 | return cnt; | |
5940 | } | |
5941 | ||
5942 | static const struct file_operations rb_simple_fops = { | |
7b85af63 | 5943 | .open = tracing_open_generic_tr, |
499e5470 SR |
5944 | .read = rb_simple_read, |
5945 | .write = rb_simple_write, | |
7b85af63 | 5946 | .release = tracing_release_generic_tr, |
499e5470 SR |
5947 | .llseek = default_llseek, |
5948 | }; | |
5949 | ||
277ba044 SR |
5950 | struct dentry *trace_instance_dir; |
5951 | ||
5952 | static void | |
5953 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer); | |
5954 | ||
55034cd6 SRRH |
5955 | static int |
5956 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
5957 | { |
5958 | enum ring_buffer_flags rb_flags; | |
737223fb SRRH |
5959 | |
5960 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; | |
5961 | ||
dced341b SRRH |
5962 | buf->tr = tr; |
5963 | ||
55034cd6 SRRH |
5964 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
5965 | if (!buf->buffer) | |
5966 | return -ENOMEM; | |
737223fb | 5967 | |
55034cd6 SRRH |
5968 | buf->data = alloc_percpu(struct trace_array_cpu); |
5969 | if (!buf->data) { | |
5970 | ring_buffer_free(buf->buffer); | |
5971 | return -ENOMEM; | |
5972 | } | |
737223fb | 5973 | |
737223fb SRRH |
5974 | /* Allocate the first page for all buffers */ |
5975 | set_buffer_entries(&tr->trace_buffer, | |
5976 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
5977 | ||
55034cd6 SRRH |
5978 | return 0; |
5979 | } | |
737223fb | 5980 | |
55034cd6 SRRH |
5981 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
5982 | { | |
5983 | int ret; | |
737223fb | 5984 | |
55034cd6 SRRH |
5985 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
5986 | if (ret) | |
5987 | return ret; | |
737223fb | 5988 | |
55034cd6 SRRH |
5989 | #ifdef CONFIG_TRACER_MAX_TRACE |
5990 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
5991 | allocate_snapshot ? size : 1); | |
5992 | if (WARN_ON(ret)) { | |
737223fb | 5993 | ring_buffer_free(tr->trace_buffer.buffer); |
55034cd6 SRRH |
5994 | free_percpu(tr->trace_buffer.data); |
5995 | return -ENOMEM; | |
5996 | } | |
5997 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 5998 | |
55034cd6 SRRH |
5999 | /* |
6000 | * Only the top level trace array gets its snapshot allocated | |
6001 | * from the kernel command line. | |
6002 | */ | |
6003 | allocate_snapshot = false; | |
737223fb | 6004 | #endif |
55034cd6 | 6005 | return 0; |
737223fb SRRH |
6006 | } |
6007 | ||
6008 | static int new_instance_create(const char *name) | |
6009 | { | |
277ba044 SR |
6010 | struct trace_array *tr; |
6011 | int ret; | |
277ba044 SR |
6012 | |
6013 | mutex_lock(&trace_types_lock); | |
6014 | ||
6015 | ret = -EEXIST; | |
6016 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6017 | if (tr->name && strcmp(tr->name, name) == 0) | |
6018 | goto out_unlock; | |
6019 | } | |
6020 | ||
6021 | ret = -ENOMEM; | |
6022 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
6023 | if (!tr) | |
6024 | goto out_unlock; | |
6025 | ||
6026 | tr->name = kstrdup(name, GFP_KERNEL); | |
6027 | if (!tr->name) | |
6028 | goto out_free_tr; | |
6029 | ||
ccfe9e42 AL |
6030 | if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) |
6031 | goto out_free_tr; | |
6032 | ||
6033 | cpumask_copy(tr->tracing_cpumask, cpu_all_mask); | |
6034 | ||
277ba044 SR |
6035 | raw_spin_lock_init(&tr->start_lock); |
6036 | ||
6037 | tr->current_trace = &nop_trace; | |
6038 | ||
6039 | INIT_LIST_HEAD(&tr->systems); | |
6040 | INIT_LIST_HEAD(&tr->events); | |
6041 | ||
737223fb | 6042 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
6043 | goto out_free_tr; |
6044 | ||
277ba044 SR |
6045 | tr->dir = debugfs_create_dir(name, trace_instance_dir); |
6046 | if (!tr->dir) | |
6047 | goto out_free_tr; | |
6048 | ||
6049 | ret = event_trace_add_tracer(tr->dir, tr); | |
609e85a7 AL |
6050 | if (ret) { |
6051 | debugfs_remove_recursive(tr->dir); | |
277ba044 | 6052 | goto out_free_tr; |
609e85a7 | 6053 | } |
277ba044 SR |
6054 | |
6055 | init_tracer_debugfs(tr, tr->dir); | |
6056 | ||
6057 | list_add(&tr->list, &ftrace_trace_arrays); | |
6058 | ||
6059 | mutex_unlock(&trace_types_lock); | |
6060 | ||
6061 | return 0; | |
6062 | ||
6063 | out_free_tr: | |
12883efb SRRH |
6064 | if (tr->trace_buffer.buffer) |
6065 | ring_buffer_free(tr->trace_buffer.buffer); | |
ccfe9e42 | 6066 | free_cpumask_var(tr->tracing_cpumask); |
277ba044 SR |
6067 | kfree(tr->name); |
6068 | kfree(tr); | |
6069 | ||
6070 | out_unlock: | |
6071 | mutex_unlock(&trace_types_lock); | |
6072 | ||
6073 | return ret; | |
6074 | ||
6075 | } | |
6076 | ||
0c8916c3 SR |
6077 | static int instance_delete(const char *name) |
6078 | { | |
6079 | struct trace_array *tr; | |
6080 | int found = 0; | |
6081 | int ret; | |
6082 | ||
6083 | mutex_lock(&trace_types_lock); | |
6084 | ||
6085 | ret = -ENODEV; | |
6086 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6087 | if (tr->name && strcmp(tr->name, name) == 0) { | |
6088 | found = 1; | |
6089 | break; | |
6090 | } | |
6091 | } | |
6092 | if (!found) | |
6093 | goto out_unlock; | |
6094 | ||
a695cb58 SRRH |
6095 | ret = -EBUSY; |
6096 | if (tr->ref) | |
6097 | goto out_unlock; | |
6098 | ||
0c8916c3 SR |
6099 | list_del(&tr->list); |
6100 | ||
6101 | event_trace_del_tracer(tr); | |
6102 | debugfs_remove_recursive(tr->dir); | |
12883efb SRRH |
6103 | free_percpu(tr->trace_buffer.data); |
6104 | ring_buffer_free(tr->trace_buffer.buffer); | |
0c8916c3 SR |
6105 | |
6106 | kfree(tr->name); | |
6107 | kfree(tr); | |
6108 | ||
6109 | ret = 0; | |
6110 | ||
6111 | out_unlock: | |
6112 | mutex_unlock(&trace_types_lock); | |
6113 | ||
6114 | return ret; | |
6115 | } | |
6116 | ||
277ba044 SR |
6117 | static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t mode) |
6118 | { | |
6119 | struct dentry *parent; | |
6120 | int ret; | |
6121 | ||
6122 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
6123 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
6124 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
6125 | return -ENOENT; | |
6126 | ||
6127 | /* | |
6128 | * The inode mutex is locked, but debugfs_create_dir() will also | |
6129 | * take the mutex. As the instances directory can not be destroyed | |
6130 | * or changed in any other way, it is safe to unlock it, and | |
6131 | * let the dentry try. If two users try to make the same dir at | |
6132 | * the same time, then the new_instance_create() will determine the | |
6133 | * winner. | |
6134 | */ | |
6135 | mutex_unlock(&inode->i_mutex); | |
6136 | ||
6137 | ret = new_instance_create(dentry->d_iname); | |
6138 | ||
6139 | mutex_lock(&inode->i_mutex); | |
6140 | ||
6141 | return ret; | |
6142 | } | |
6143 | ||
0c8916c3 SR |
6144 | static int instance_rmdir(struct inode *inode, struct dentry *dentry) |
6145 | { | |
6146 | struct dentry *parent; | |
6147 | int ret; | |
6148 | ||
6149 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
6150 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
6151 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
6152 | return -ENOENT; | |
6153 | ||
6154 | /* The caller did a dget() on dentry */ | |
6155 | mutex_unlock(&dentry->d_inode->i_mutex); | |
6156 | ||
6157 | /* | |
6158 | * The inode mutex is locked, but debugfs_create_dir() will also | |
6159 | * take the mutex. As the instances directory can not be destroyed | |
6160 | * or changed in any other way, it is safe to unlock it, and | |
6161 | * let the dentry try. If two users try to make the same dir at | |
6162 | * the same time, then the instance_delete() will determine the | |
6163 | * winner. | |
6164 | */ | |
6165 | mutex_unlock(&inode->i_mutex); | |
6166 | ||
6167 | ret = instance_delete(dentry->d_iname); | |
6168 | ||
6169 | mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); | |
6170 | mutex_lock(&dentry->d_inode->i_mutex); | |
6171 | ||
6172 | return ret; | |
6173 | } | |
6174 | ||
277ba044 SR |
6175 | static const struct inode_operations instance_dir_inode_operations = { |
6176 | .lookup = simple_lookup, | |
6177 | .mkdir = instance_mkdir, | |
0c8916c3 | 6178 | .rmdir = instance_rmdir, |
277ba044 SR |
6179 | }; |
6180 | ||
6181 | static __init void create_trace_instances(struct dentry *d_tracer) | |
6182 | { | |
6183 | trace_instance_dir = debugfs_create_dir("instances", d_tracer); | |
6184 | if (WARN_ON(!trace_instance_dir)) | |
6185 | return; | |
6186 | ||
6187 | /* Hijack the dir inode operations, to allow mkdir */ | |
6188 | trace_instance_dir->d_inode->i_op = &instance_dir_inode_operations; | |
6189 | } | |
6190 | ||
2b6080f2 SR |
6191 | static void |
6192 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) | |
6193 | { | |
121aaee7 | 6194 | int cpu; |
2b6080f2 | 6195 | |
ccfe9e42 AL |
6196 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
6197 | tr, &tracing_cpumask_fops); | |
6198 | ||
2b6080f2 SR |
6199 | trace_create_file("trace_options", 0644, d_tracer, |
6200 | tr, &tracing_iter_fops); | |
6201 | ||
6202 | trace_create_file("trace", 0644, d_tracer, | |
6484c71c | 6203 | tr, &tracing_fops); |
2b6080f2 SR |
6204 | |
6205 | trace_create_file("trace_pipe", 0444, d_tracer, | |
15544209 | 6206 | tr, &tracing_pipe_fops); |
2b6080f2 SR |
6207 | |
6208 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
0bc392ee | 6209 | tr, &tracing_entries_fops); |
2b6080f2 SR |
6210 | |
6211 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
6212 | tr, &tracing_total_entries_fops); | |
6213 | ||
238ae93d | 6214 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
6215 | tr, &tracing_free_buffer_fops); |
6216 | ||
6217 | trace_create_file("trace_marker", 0220, d_tracer, | |
6218 | tr, &tracing_mark_fops); | |
6219 | ||
6220 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
6221 | &trace_clock_fops); | |
6222 | ||
6223 | trace_create_file("tracing_on", 0644, d_tracer, | |
6484c71c | 6224 | tr, &rb_simple_fops); |
ce9bae55 SRRH |
6225 | |
6226 | #ifdef CONFIG_TRACER_SNAPSHOT | |
6227 | trace_create_file("snapshot", 0644, d_tracer, | |
6484c71c | 6228 | tr, &snapshot_fops); |
ce9bae55 | 6229 | #endif |
121aaee7 SRRH |
6230 | |
6231 | for_each_tracing_cpu(cpu) | |
6232 | tracing_init_debugfs_percpu(tr, cpu); | |
6233 | ||
2b6080f2 SR |
6234 | } |
6235 | ||
b5ad384e | 6236 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
6237 | { |
6238 | struct dentry *d_tracer; | |
bc0c38d1 | 6239 | |
7e53bd42 LJ |
6240 | trace_access_lock_init(); |
6241 | ||
bc0c38d1 | 6242 | d_tracer = tracing_init_dentry(); |
ed6f1c99 NK |
6243 | if (!d_tracer) |
6244 | return 0; | |
bc0c38d1 | 6245 | |
2b6080f2 | 6246 | init_tracer_debugfs(&global_trace, d_tracer); |
bc0c38d1 | 6247 | |
5452af66 FW |
6248 | trace_create_file("available_tracers", 0444, d_tracer, |
6249 | &global_trace, &show_traces_fops); | |
6250 | ||
339ae5d3 | 6251 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
6252 | &global_trace, &set_tracer_fops); |
6253 | ||
5d4a9dba | 6254 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
6255 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
6256 | &tracing_max_latency, &tracing_max_lat_fops); | |
0e950173 | 6257 | #endif |
5452af66 FW |
6258 | |
6259 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
6260 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 6261 | |
339ae5d3 | 6262 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
6263 | NULL, &tracing_readme_fops); |
6264 | ||
69abe6a5 AP |
6265 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
6266 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 6267 | |
bc0c38d1 | 6268 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
6269 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
6270 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 6271 | #endif |
b04cc6b1 | 6272 | |
277ba044 | 6273 | create_trace_instances(d_tracer); |
5452af66 | 6274 | |
2b6080f2 | 6275 | create_trace_options_dir(&global_trace); |
b04cc6b1 | 6276 | |
b5ad384e | 6277 | return 0; |
bc0c38d1 SR |
6278 | } |
6279 | ||
3f5a54e3 SR |
6280 | static int trace_panic_handler(struct notifier_block *this, |
6281 | unsigned long event, void *unused) | |
6282 | { | |
944ac425 | 6283 | if (ftrace_dump_on_oops) |
cecbca96 | 6284 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6285 | return NOTIFY_OK; |
6286 | } | |
6287 | ||
6288 | static struct notifier_block trace_panic_notifier = { | |
6289 | .notifier_call = trace_panic_handler, | |
6290 | .next = NULL, | |
6291 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
6292 | }; | |
6293 | ||
6294 | static int trace_die_handler(struct notifier_block *self, | |
6295 | unsigned long val, | |
6296 | void *data) | |
6297 | { | |
6298 | switch (val) { | |
6299 | case DIE_OOPS: | |
944ac425 | 6300 | if (ftrace_dump_on_oops) |
cecbca96 | 6301 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6302 | break; |
6303 | default: | |
6304 | break; | |
6305 | } | |
6306 | return NOTIFY_OK; | |
6307 | } | |
6308 | ||
6309 | static struct notifier_block trace_die_notifier = { | |
6310 | .notifier_call = trace_die_handler, | |
6311 | .priority = 200 | |
6312 | }; | |
6313 | ||
6314 | /* | |
6315 | * printk is set to max of 1024, we really don't need it that big. | |
6316 | * Nothing should be printing 1000 characters anyway. | |
6317 | */ | |
6318 | #define TRACE_MAX_PRINT 1000 | |
6319 | ||
6320 | /* | |
6321 | * Define here KERN_TRACE so that we have one place to modify | |
6322 | * it if we decide to change what log level the ftrace dump | |
6323 | * should be at. | |
6324 | */ | |
428aee14 | 6325 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 6326 | |
955b61e5 | 6327 | void |
3f5a54e3 SR |
6328 | trace_printk_seq(struct trace_seq *s) |
6329 | { | |
6330 | /* Probably should print a warning here. */ | |
bd6df187 J |
6331 | if (s->len >= TRACE_MAX_PRINT) |
6332 | s->len = TRACE_MAX_PRINT; | |
3f5a54e3 SR |
6333 | |
6334 | /* should be zero ended, but we are paranoid. */ | |
6335 | s->buffer[s->len] = 0; | |
6336 | ||
6337 | printk(KERN_TRACE "%s", s->buffer); | |
6338 | ||
f9520750 | 6339 | trace_seq_init(s); |
3f5a54e3 SR |
6340 | } |
6341 | ||
955b61e5 JW |
6342 | void trace_init_global_iter(struct trace_iterator *iter) |
6343 | { | |
6344 | iter->tr = &global_trace; | |
2b6080f2 | 6345 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 6346 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 6347 | iter->trace_buffer = &global_trace.trace_buffer; |
b2f974d6 CS |
6348 | |
6349 | if (iter->trace && iter->trace->open) | |
6350 | iter->trace->open(iter); | |
6351 | ||
6352 | /* Annotate start of buffers if we had overruns */ | |
6353 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) | |
6354 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
6355 | ||
6356 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ | |
6357 | if (trace_clocks[iter->tr->clock_id].in_ns) | |
6358 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
955b61e5 JW |
6359 | } |
6360 | ||
7fe70b57 | 6361 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 6362 | { |
3f5a54e3 SR |
6363 | /* use static because iter can be a bit big for the stack */ |
6364 | static struct trace_iterator iter; | |
7fe70b57 | 6365 | static atomic_t dump_running; |
cf586b61 | 6366 | unsigned int old_userobj; |
d769041f SR |
6367 | unsigned long flags; |
6368 | int cnt = 0, cpu; | |
3f5a54e3 | 6369 | |
7fe70b57 SRRH |
6370 | /* Only allow one dump user at a time. */ |
6371 | if (atomic_inc_return(&dump_running) != 1) { | |
6372 | atomic_dec(&dump_running); | |
6373 | return; | |
6374 | } | |
3f5a54e3 | 6375 | |
7fe70b57 SRRH |
6376 | /* |
6377 | * Always turn off tracing when we dump. | |
6378 | * We don't need to show trace output of what happens | |
6379 | * between multiple crashes. | |
6380 | * | |
6381 | * If the user does a sysrq-z, then they can re-enable | |
6382 | * tracing with echo 1 > tracing_on. | |
6383 | */ | |
0ee6b6cf | 6384 | tracing_off(); |
cf586b61 | 6385 | |
7fe70b57 | 6386 | local_irq_save(flags); |
3f5a54e3 | 6387 | |
38dbe0b1 | 6388 | /* Simulate the iterator */ |
955b61e5 JW |
6389 | trace_init_global_iter(&iter); |
6390 | ||
d769041f | 6391 | for_each_tracing_cpu(cpu) { |
12883efb | 6392 | atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled); |
d769041f SR |
6393 | } |
6394 | ||
cf586b61 FW |
6395 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
6396 | ||
b54d3de9 TE |
6397 | /* don't look at user memory in panic mode */ |
6398 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
6399 | ||
cecbca96 FW |
6400 | switch (oops_dump_mode) { |
6401 | case DUMP_ALL: | |
ae3b5093 | 6402 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6403 | break; |
6404 | case DUMP_ORIG: | |
6405 | iter.cpu_file = raw_smp_processor_id(); | |
6406 | break; | |
6407 | case DUMP_NONE: | |
6408 | goto out_enable; | |
6409 | default: | |
6410 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 6411 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6412 | } |
6413 | ||
6414 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 6415 | |
7fe70b57 SRRH |
6416 | /* Did function tracer already get disabled? */ |
6417 | if (ftrace_is_dead()) { | |
6418 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
6419 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
6420 | } | |
6421 | ||
3f5a54e3 SR |
6422 | /* |
6423 | * We need to stop all tracing on all CPUS to read the | |
6424 | * the next buffer. This is a bit expensive, but is | |
6425 | * not done often. We fill all what we can read, | |
6426 | * and then release the locks again. | |
6427 | */ | |
6428 | ||
3f5a54e3 SR |
6429 | while (!trace_empty(&iter)) { |
6430 | ||
6431 | if (!cnt) | |
6432 | printk(KERN_TRACE "---------------------------------\n"); | |
6433 | ||
6434 | cnt++; | |
6435 | ||
6436 | /* reset all but tr, trace, and overruns */ | |
6437 | memset(&iter.seq, 0, | |
6438 | sizeof(struct trace_iterator) - | |
6439 | offsetof(struct trace_iterator, seq)); | |
6440 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
6441 | iter.pos = -1; | |
6442 | ||
955b61e5 | 6443 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
6444 | int ret; |
6445 | ||
6446 | ret = print_trace_line(&iter); | |
6447 | if (ret != TRACE_TYPE_NO_CONSUME) | |
6448 | trace_consume(&iter); | |
3f5a54e3 | 6449 | } |
b892e5c8 | 6450 | touch_nmi_watchdog(); |
3f5a54e3 SR |
6451 | |
6452 | trace_printk_seq(&iter.seq); | |
6453 | } | |
6454 | ||
6455 | if (!cnt) | |
6456 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
6457 | else | |
6458 | printk(KERN_TRACE "---------------------------------\n"); | |
6459 | ||
cecbca96 | 6460 | out_enable: |
7fe70b57 | 6461 | trace_flags |= old_userobj; |
cf586b61 | 6462 | |
7fe70b57 SRRH |
6463 | for_each_tracing_cpu(cpu) { |
6464 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); | |
cf586b61 | 6465 | } |
7fe70b57 | 6466 | atomic_dec(&dump_running); |
cd891ae0 | 6467 | local_irq_restore(flags); |
3f5a54e3 | 6468 | } |
a8eecf22 | 6469 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 6470 | |
3928a8a2 | 6471 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 6472 | { |
73c5162a | 6473 | int ring_buf_size; |
9e01c1b7 | 6474 | int ret = -ENOMEM; |
4c11d7ae | 6475 | |
750912fa | 6476 | |
9e01c1b7 RR |
6477 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
6478 | goto out; | |
6479 | ||
ccfe9e42 | 6480 | if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) |
9e01c1b7 | 6481 | goto out_free_buffer_mask; |
4c11d7ae | 6482 | |
07d777fe SR |
6483 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
6484 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 6485 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
6486 | trace_printk_init_buffers(); |
6487 | ||
73c5162a SR |
6488 | /* To save memory, keep the ring buffer size to its minimum */ |
6489 | if (ring_buffer_expanded) | |
6490 | ring_buf_size = trace_buf_size; | |
6491 | else | |
6492 | ring_buf_size = 1; | |
6493 | ||
9e01c1b7 | 6494 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
ccfe9e42 | 6495 | cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); |
9e01c1b7 | 6496 | |
2b6080f2 SR |
6497 | raw_spin_lock_init(&global_trace.start_lock); |
6498 | ||
9e01c1b7 | 6499 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 6500 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
6501 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
6502 | WARN_ON(1); | |
9e01c1b7 | 6503 | goto out_free_cpumask; |
4c11d7ae | 6504 | } |
a7603ff4 | 6505 | |
499e5470 SR |
6506 | if (global_trace.buffer_disabled) |
6507 | tracing_off(); | |
4c11d7ae | 6508 | |
bc0c38d1 SR |
6509 | trace_init_cmdlines(); |
6510 | ||
ca164318 SRRH |
6511 | /* |
6512 | * register_tracer() might reference current_trace, so it | |
6513 | * needs to be set before we register anything. This is | |
6514 | * just a bootstrap of current_trace anyway. | |
6515 | */ | |
2b6080f2 SR |
6516 | global_trace.current_trace = &nop_trace; |
6517 | ||
ca164318 SRRH |
6518 | register_tracer(&nop_trace); |
6519 | ||
60a11774 SR |
6520 | /* All seems OK, enable tracing */ |
6521 | tracing_disabled = 0; | |
3928a8a2 | 6522 | |
3f5a54e3 SR |
6523 | atomic_notifier_chain_register(&panic_notifier_list, |
6524 | &trace_panic_notifier); | |
6525 | ||
6526 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 6527 | |
ae63b31e SR |
6528 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
6529 | ||
6530 | INIT_LIST_HEAD(&global_trace.systems); | |
6531 | INIT_LIST_HEAD(&global_trace.events); | |
6532 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
6533 | ||
7bcfaf54 SR |
6534 | while (trace_boot_options) { |
6535 | char *option; | |
6536 | ||
6537 | option = strsep(&trace_boot_options, ","); | |
2b6080f2 | 6538 | trace_set_options(&global_trace, option); |
7bcfaf54 SR |
6539 | } |
6540 | ||
77fd5c15 SRRH |
6541 | register_snapshot_cmd(); |
6542 | ||
2fc1dfbe | 6543 | return 0; |
3f5a54e3 | 6544 | |
9e01c1b7 | 6545 | out_free_cpumask: |
12883efb SRRH |
6546 | free_percpu(global_trace.trace_buffer.data); |
6547 | #ifdef CONFIG_TRACER_MAX_TRACE | |
6548 | free_percpu(global_trace.max_buffer.data); | |
6549 | #endif | |
ccfe9e42 | 6550 | free_cpumask_var(global_trace.tracing_cpumask); |
9e01c1b7 RR |
6551 | out_free_buffer_mask: |
6552 | free_cpumask_var(tracing_buffer_mask); | |
6553 | out: | |
6554 | return ret; | |
bc0c38d1 | 6555 | } |
b2821ae6 SR |
6556 | |
6557 | __init static int clear_boot_tracer(void) | |
6558 | { | |
6559 | /* | |
6560 | * The default tracer at boot buffer is an init section. | |
6561 | * This function is called in lateinit. If we did not | |
6562 | * find the boot tracer, then clear it out, to prevent | |
6563 | * later registration from accessing the buffer that is | |
6564 | * about to be freed. | |
6565 | */ | |
6566 | if (!default_bootup_tracer) | |
6567 | return 0; | |
6568 | ||
6569 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
6570 | default_bootup_tracer); | |
6571 | default_bootup_tracer = NULL; | |
6572 | ||
6573 | return 0; | |
6574 | } | |
6575 | ||
b5ad384e FW |
6576 | early_initcall(tracer_alloc_buffers); |
6577 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 6578 | late_initcall(clear_boot_tracer); |