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