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Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
2b6080f2 | 4 | * Copyright (C) 2007-2012 Steven Rostedt <srostedt@redhat.com> |
bc0c38d1 SR |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
6d49e352 | 12 | * Copyright (C) 2004 Nadia Yvette Chambers |
bc0c38d1 | 13 | */ |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
273b281f | 15 | #include <generated/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
4c11d7ae | 23 | #include <linux/pagemap.h> |
bc0c38d1 SR |
24 | #include <linux/hardirq.h> |
25 | #include <linux/linkage.h> | |
26 | #include <linux/uaccess.h> | |
2cadf913 | 27 | #include <linux/kprobes.h> |
bc0c38d1 SR |
28 | #include <linux/ftrace.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/percpu.h> | |
2cadf913 | 31 | #include <linux/splice.h> |
3f5a54e3 | 32 | #include <linux/kdebug.h> |
5f0c6c03 | 33 | #include <linux/string.h> |
7e53bd42 | 34 | #include <linux/rwsem.h> |
5a0e3ad6 | 35 | #include <linux/slab.h> |
bc0c38d1 SR |
36 | #include <linux/ctype.h> |
37 | #include <linux/init.h> | |
2a2cc8f7 | 38 | #include <linux/poll.h> |
b892e5c8 | 39 | #include <linux/nmi.h> |
bc0c38d1 | 40 | #include <linux/fs.h> |
8bd75c77 | 41 | #include <linux/sched/rt.h> |
86387f7e | 42 | |
bc0c38d1 | 43 | #include "trace.h" |
f0868d1e | 44 | #include "trace_output.h" |
bc0c38d1 | 45 | |
73c5162a SR |
46 | /* |
47 | * On boot up, the ring buffer is set to the minimum size, so that | |
48 | * we do not waste memory on systems that are not using tracing. | |
49 | */ | |
55034cd6 | 50 | bool ring_buffer_expanded; |
73c5162a | 51 | |
8e1b82e0 FW |
52 | /* |
53 | * We need to change this state when a selftest is running. | |
ff32504f FW |
54 | * A selftest will lurk into the ring-buffer to count the |
55 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 56 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
57 | * at the same time, giving false positive or negative results. |
58 | */ | |
8e1b82e0 | 59 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 60 | |
b2821ae6 SR |
61 | /* |
62 | * If a tracer is running, we do not want to run SELFTEST. | |
63 | */ | |
020e5f85 | 64 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 65 | |
adf9f195 FW |
66 | /* For tracers that don't implement custom flags */ |
67 | static struct tracer_opt dummy_tracer_opt[] = { | |
68 | { } | |
69 | }; | |
70 | ||
71 | static struct tracer_flags dummy_tracer_flags = { | |
72 | .val = 0, | |
73 | .opts = dummy_tracer_opt | |
74 | }; | |
75 | ||
8c1a49ae SRRH |
76 | static int |
77 | dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) | |
adf9f195 FW |
78 | { |
79 | return 0; | |
80 | } | |
0f048701 | 81 | |
7ffbd48d SR |
82 | /* |
83 | * To prevent the comm cache from being overwritten when no | |
84 | * tracing is active, only save the comm when a trace event | |
85 | * occurred. | |
86 | */ | |
87 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
88 | ||
0f048701 SR |
89 | /* |
90 | * Kill all tracing for good (never come back). | |
91 | * It is initialized to 1 but will turn to zero if the initialization | |
92 | * of the tracer is successful. But that is the only place that sets | |
93 | * this back to zero. | |
94 | */ | |
4fd27358 | 95 | static int tracing_disabled = 1; |
0f048701 | 96 | |
9288f99a | 97 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 98 | |
955b61e5 | 99 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 100 | |
944ac425 SR |
101 | /* |
102 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
103 | * | |
104 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
105 | * is set, then ftrace_dump is called. This will output the contents | |
106 | * of the ftrace buffers to the console. This is very useful for | |
107 | * capturing traces that lead to crashes and outputing it to a | |
108 | * serial console. | |
109 | * | |
110 | * It is default off, but you can enable it with either specifying | |
111 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
112 | * /proc/sys/kernel/ftrace_dump_on_oops |
113 | * Set 1 if you want to dump buffers of all CPUs | |
114 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 115 | */ |
cecbca96 FW |
116 | |
117 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 118 | |
de7edd31 SRRH |
119 | /* When set, tracing will stop when a WARN*() is hit */ |
120 | int __disable_trace_on_warning; | |
121 | ||
607e2ea1 | 122 | static int tracing_set_tracer(struct trace_array *tr, const char *buf); |
b2821ae6 | 123 | |
ee6c2c1b LZ |
124 | #define MAX_TRACER_SIZE 100 |
125 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 126 | static char *default_bootup_tracer; |
d9e54076 | 127 | |
55034cd6 SRRH |
128 | static bool allocate_snapshot; |
129 | ||
1beee96b | 130 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 131 | { |
67012ab1 | 132 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 133 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 134 | /* We are using ftrace early, expand it */ |
55034cd6 | 135 | ring_buffer_expanded = true; |
d9e54076 PZ |
136 | return 1; |
137 | } | |
1beee96b | 138 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 139 | |
944ac425 SR |
140 | static int __init set_ftrace_dump_on_oops(char *str) |
141 | { | |
cecbca96 FW |
142 | if (*str++ != '=' || !*str) { |
143 | ftrace_dump_on_oops = DUMP_ALL; | |
144 | return 1; | |
145 | } | |
146 | ||
147 | if (!strcmp("orig_cpu", str)) { | |
148 | ftrace_dump_on_oops = DUMP_ORIG; | |
149 | return 1; | |
150 | } | |
151 | ||
152 | return 0; | |
944ac425 SR |
153 | } |
154 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 155 | |
de7edd31 SRRH |
156 | static int __init stop_trace_on_warning(char *str) |
157 | { | |
158 | __disable_trace_on_warning = 1; | |
159 | return 1; | |
160 | } | |
161 | __setup("traceoff_on_warning=", stop_trace_on_warning); | |
162 | ||
3209cff4 | 163 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
164 | { |
165 | allocate_snapshot = true; | |
166 | /* We also need the main ring buffer expanded */ | |
167 | ring_buffer_expanded = true; | |
168 | return 1; | |
169 | } | |
3209cff4 | 170 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 171 | |
7bcfaf54 SR |
172 | |
173 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
174 | static char *trace_boot_options __initdata; | |
175 | ||
176 | static int __init set_trace_boot_options(char *str) | |
177 | { | |
67012ab1 | 178 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
179 | trace_boot_options = trace_boot_options_buf; |
180 | return 0; | |
181 | } | |
182 | __setup("trace_options=", set_trace_boot_options); | |
183 | ||
e1e232ca SR |
184 | static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; |
185 | static char *trace_boot_clock __initdata; | |
186 | ||
187 | static int __init set_trace_boot_clock(char *str) | |
188 | { | |
189 | strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); | |
190 | trace_boot_clock = trace_boot_clock_buf; | |
191 | return 0; | |
192 | } | |
193 | __setup("trace_clock=", set_trace_boot_clock); | |
194 | ||
de7edd31 | 195 | |
cf8e3474 | 196 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
197 | { |
198 | nsec += 500; | |
199 | do_div(nsec, 1000); | |
200 | return nsec; | |
201 | } | |
202 | ||
4fcdae83 SR |
203 | /* |
204 | * The global_trace is the descriptor that holds the tracing | |
205 | * buffers for the live tracing. For each CPU, it contains | |
206 | * a link list of pages that will store trace entries. The | |
207 | * page descriptor of the pages in the memory is used to hold | |
208 | * the link list by linking the lru item in the page descriptor | |
209 | * to each of the pages in the buffer per CPU. | |
210 | * | |
211 | * For each active CPU there is a data field that holds the | |
212 | * pages for the buffer for that CPU. Each CPU has the same number | |
213 | * of pages allocated for its buffer. | |
214 | */ | |
bc0c38d1 SR |
215 | static struct trace_array global_trace; |
216 | ||
ae63b31e | 217 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 218 | |
ff451961 SRRH |
219 | int trace_array_get(struct trace_array *this_tr) |
220 | { | |
221 | struct trace_array *tr; | |
222 | int ret = -ENODEV; | |
223 | ||
224 | mutex_lock(&trace_types_lock); | |
225 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
226 | if (tr == this_tr) { | |
227 | tr->ref++; | |
228 | ret = 0; | |
229 | break; | |
230 | } | |
231 | } | |
232 | mutex_unlock(&trace_types_lock); | |
233 | ||
234 | return ret; | |
235 | } | |
236 | ||
237 | static void __trace_array_put(struct trace_array *this_tr) | |
238 | { | |
239 | WARN_ON(!this_tr->ref); | |
240 | this_tr->ref--; | |
241 | } | |
242 | ||
243 | void trace_array_put(struct trace_array *this_tr) | |
244 | { | |
245 | mutex_lock(&trace_types_lock); | |
246 | __trace_array_put(this_tr); | |
247 | mutex_unlock(&trace_types_lock); | |
248 | } | |
249 | ||
f306cc82 TZ |
250 | int filter_check_discard(struct ftrace_event_file *file, void *rec, |
251 | struct ring_buffer *buffer, | |
252 | struct ring_buffer_event *event) | |
eb02ce01 | 253 | { |
f306cc82 TZ |
254 | if (unlikely(file->flags & FTRACE_EVENT_FL_FILTERED) && |
255 | !filter_match_preds(file->filter, rec)) { | |
256 | ring_buffer_discard_commit(buffer, event); | |
257 | return 1; | |
258 | } | |
259 | ||
260 | return 0; | |
261 | } | |
262 | EXPORT_SYMBOL_GPL(filter_check_discard); | |
263 | ||
264 | int call_filter_check_discard(struct ftrace_event_call *call, void *rec, | |
265 | struct ring_buffer *buffer, | |
266 | struct ring_buffer_event *event) | |
267 | { | |
268 | if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && | |
269 | !filter_match_preds(call->filter, rec)) { | |
270 | ring_buffer_discard_commit(buffer, event); | |
271 | return 1; | |
272 | } | |
273 | ||
274 | return 0; | |
eb02ce01 | 275 | } |
f306cc82 | 276 | EXPORT_SYMBOL_GPL(call_filter_check_discard); |
eb02ce01 | 277 | |
ad1438a0 | 278 | static cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) |
37886f6a SR |
279 | { |
280 | u64 ts; | |
281 | ||
282 | /* Early boot up does not have a buffer yet */ | |
9457158b | 283 | if (!buf->buffer) |
37886f6a SR |
284 | return trace_clock_local(); |
285 | ||
9457158b AL |
286 | ts = ring_buffer_time_stamp(buf->buffer, cpu); |
287 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); | |
37886f6a SR |
288 | |
289 | return ts; | |
290 | } | |
bc0c38d1 | 291 | |
9457158b AL |
292 | cycle_t ftrace_now(int cpu) |
293 | { | |
294 | return buffer_ftrace_now(&global_trace.trace_buffer, cpu); | |
295 | } | |
296 | ||
10246fa3 SRRH |
297 | /** |
298 | * tracing_is_enabled - Show if global_trace has been disabled | |
299 | * | |
300 | * Shows if the global trace has been enabled or not. It uses the | |
301 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
302 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
303 | * need to know the accurate state, use tracing_is_on() which is a little | |
304 | * slower, but accurate. | |
305 | */ | |
9036990d SR |
306 | int tracing_is_enabled(void) |
307 | { | |
10246fa3 SRRH |
308 | /* |
309 | * For quick access (irqsoff uses this in fast path), just | |
310 | * return the mirror variable of the state of the ring buffer. | |
311 | * It's a little racy, but we don't really care. | |
312 | */ | |
313 | smp_rmb(); | |
314 | return !global_trace.buffer_disabled; | |
9036990d SR |
315 | } |
316 | ||
4fcdae83 | 317 | /* |
3928a8a2 SR |
318 | * trace_buf_size is the size in bytes that is allocated |
319 | * for a buffer. Note, the number of bytes is always rounded | |
320 | * to page size. | |
3f5a54e3 SR |
321 | * |
322 | * This number is purposely set to a low number of 16384. | |
323 | * If the dump on oops happens, it will be much appreciated | |
324 | * to not have to wait for all that output. Anyway this can be | |
325 | * boot time and run time configurable. | |
4fcdae83 | 326 | */ |
3928a8a2 | 327 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 328 | |
3928a8a2 | 329 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 330 | |
4fcdae83 | 331 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 332 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 333 | |
4fcdae83 SR |
334 | /* |
335 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 336 | */ |
a8227415 | 337 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 338 | |
7e53bd42 LJ |
339 | /* |
340 | * serialize the access of the ring buffer | |
341 | * | |
342 | * ring buffer serializes readers, but it is low level protection. | |
343 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
344 | * are not protected by ring buffer. | |
345 | * | |
346 | * The content of events may become garbage if we allow other process consumes | |
347 | * these events concurrently: | |
348 | * A) the page of the consumed events may become a normal page | |
349 | * (not reader page) in ring buffer, and this page will be rewrited | |
350 | * by events producer. | |
351 | * B) The page of the consumed events may become a page for splice_read, | |
352 | * and this page will be returned to system. | |
353 | * | |
354 | * These primitives allow multi process access to different cpu ring buffer | |
355 | * concurrently. | |
356 | * | |
357 | * These primitives don't distinguish read-only and read-consume access. | |
358 | * Multi read-only access are also serialized. | |
359 | */ | |
360 | ||
361 | #ifdef CONFIG_SMP | |
362 | static DECLARE_RWSEM(all_cpu_access_lock); | |
363 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
364 | ||
365 | static inline void trace_access_lock(int cpu) | |
366 | { | |
ae3b5093 | 367 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
368 | /* gain it for accessing the whole ring buffer. */ |
369 | down_write(&all_cpu_access_lock); | |
370 | } else { | |
371 | /* gain it for accessing a cpu ring buffer. */ | |
372 | ||
ae3b5093 | 373 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
374 | down_read(&all_cpu_access_lock); |
375 | ||
376 | /* Secondly block other access to this @cpu ring buffer. */ | |
377 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
378 | } | |
379 | } | |
380 | ||
381 | static inline void trace_access_unlock(int cpu) | |
382 | { | |
ae3b5093 | 383 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
384 | up_write(&all_cpu_access_lock); |
385 | } else { | |
386 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
387 | up_read(&all_cpu_access_lock); | |
388 | } | |
389 | } | |
390 | ||
391 | static inline void trace_access_lock_init(void) | |
392 | { | |
393 | int cpu; | |
394 | ||
395 | for_each_possible_cpu(cpu) | |
396 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
397 | } | |
398 | ||
399 | #else | |
400 | ||
401 | static DEFINE_MUTEX(access_lock); | |
402 | ||
403 | static inline void trace_access_lock(int cpu) | |
404 | { | |
405 | (void)cpu; | |
406 | mutex_lock(&access_lock); | |
407 | } | |
408 | ||
409 | static inline void trace_access_unlock(int cpu) | |
410 | { | |
411 | (void)cpu; | |
412 | mutex_unlock(&access_lock); | |
413 | } | |
414 | ||
415 | static inline void trace_access_lock_init(void) | |
416 | { | |
417 | } | |
418 | ||
419 | #endif | |
420 | ||
ee6bce52 | 421 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 422 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 423 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 | 424 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
328df475 | 425 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION; |
e7e2ee89 | 426 | |
5280bcef | 427 | static void tracer_tracing_on(struct trace_array *tr) |
10246fa3 SRRH |
428 | { |
429 | if (tr->trace_buffer.buffer) | |
430 | ring_buffer_record_on(tr->trace_buffer.buffer); | |
431 | /* | |
432 | * This flag is looked at when buffers haven't been allocated | |
433 | * yet, or by some tracers (like irqsoff), that just want to | |
434 | * know if the ring buffer has been disabled, but it can handle | |
435 | * races of where it gets disabled but we still do a record. | |
436 | * As the check is in the fast path of the tracers, it is more | |
437 | * important to be fast than accurate. | |
438 | */ | |
439 | tr->buffer_disabled = 0; | |
440 | /* Make the flag seen by readers */ | |
441 | smp_wmb(); | |
442 | } | |
443 | ||
499e5470 SR |
444 | /** |
445 | * tracing_on - enable tracing buffers | |
446 | * | |
447 | * This function enables tracing buffers that may have been | |
448 | * disabled with tracing_off. | |
449 | */ | |
450 | void tracing_on(void) | |
451 | { | |
10246fa3 | 452 | tracer_tracing_on(&global_trace); |
499e5470 SR |
453 | } |
454 | EXPORT_SYMBOL_GPL(tracing_on); | |
455 | ||
09ae7234 SRRH |
456 | /** |
457 | * __trace_puts - write a constant string into the trace buffer. | |
458 | * @ip: The address of the caller | |
459 | * @str: The constant string to write | |
460 | * @size: The size of the string. | |
461 | */ | |
462 | int __trace_puts(unsigned long ip, const char *str, int size) | |
463 | { | |
464 | struct ring_buffer_event *event; | |
465 | struct ring_buffer *buffer; | |
466 | struct print_entry *entry; | |
467 | unsigned long irq_flags; | |
468 | int alloc; | |
469 | ||
3132e107 SRRH |
470 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
471 | return 0; | |
472 | ||
09ae7234 SRRH |
473 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ |
474 | ||
475 | local_save_flags(irq_flags); | |
476 | buffer = global_trace.trace_buffer.buffer; | |
477 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, | |
478 | irq_flags, preempt_count()); | |
479 | if (!event) | |
480 | return 0; | |
481 | ||
482 | entry = ring_buffer_event_data(event); | |
483 | entry->ip = ip; | |
484 | ||
485 | memcpy(&entry->buf, str, size); | |
486 | ||
487 | /* Add a newline if necessary */ | |
488 | if (entry->buf[size - 1] != '\n') { | |
489 | entry->buf[size] = '\n'; | |
490 | entry->buf[size + 1] = '\0'; | |
491 | } else | |
492 | entry->buf[size] = '\0'; | |
493 | ||
494 | __buffer_unlock_commit(buffer, event); | |
495 | ||
496 | return size; | |
497 | } | |
498 | EXPORT_SYMBOL_GPL(__trace_puts); | |
499 | ||
500 | /** | |
501 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
502 | * @ip: The address of the caller | |
503 | * @str: The constant string to write to the buffer to | |
504 | */ | |
505 | int __trace_bputs(unsigned long ip, const char *str) | |
506 | { | |
507 | struct ring_buffer_event *event; | |
508 | struct ring_buffer *buffer; | |
509 | struct bputs_entry *entry; | |
510 | unsigned long irq_flags; | |
511 | int size = sizeof(struct bputs_entry); | |
512 | ||
3132e107 SRRH |
513 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
514 | return 0; | |
515 | ||
09ae7234 SRRH |
516 | local_save_flags(irq_flags); |
517 | buffer = global_trace.trace_buffer.buffer; | |
518 | event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, | |
519 | irq_flags, preempt_count()); | |
520 | if (!event) | |
521 | return 0; | |
522 | ||
523 | entry = ring_buffer_event_data(event); | |
524 | entry->ip = ip; | |
525 | entry->str = str; | |
526 | ||
527 | __buffer_unlock_commit(buffer, event); | |
528 | ||
529 | return 1; | |
530 | } | |
531 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
532 | ||
ad909e21 SRRH |
533 | #ifdef CONFIG_TRACER_SNAPSHOT |
534 | /** | |
535 | * trace_snapshot - take a snapshot of the current buffer. | |
536 | * | |
537 | * This causes a swap between the snapshot buffer and the current live | |
538 | * tracing buffer. You can use this to take snapshots of the live | |
539 | * trace when some condition is triggered, but continue to trace. | |
540 | * | |
541 | * Note, make sure to allocate the snapshot with either | |
542 | * a tracing_snapshot_alloc(), or by doing it manually | |
543 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
544 | * | |
545 | * If the snapshot buffer is not allocated, it will stop tracing. | |
546 | * Basically making a permanent snapshot. | |
547 | */ | |
548 | void tracing_snapshot(void) | |
549 | { | |
550 | struct trace_array *tr = &global_trace; | |
551 | struct tracer *tracer = tr->current_trace; | |
552 | unsigned long flags; | |
553 | ||
1b22e382 SRRH |
554 | if (in_nmi()) { |
555 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
556 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
557 | return; | |
558 | } | |
559 | ||
ad909e21 | 560 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
561 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
562 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
563 | tracing_off(); |
564 | return; | |
565 | } | |
566 | ||
567 | /* Note, snapshot can not be used when the tracer uses it */ | |
568 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
569 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
570 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
571 | return; |
572 | } | |
573 | ||
574 | local_irq_save(flags); | |
575 | update_max_tr(tr, current, smp_processor_id()); | |
576 | local_irq_restore(flags); | |
577 | } | |
1b22e382 | 578 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
579 | |
580 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
581 | struct trace_buffer *size_buf, int cpu_id); | |
3209cff4 SRRH |
582 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); |
583 | ||
584 | static int alloc_snapshot(struct trace_array *tr) | |
585 | { | |
586 | int ret; | |
587 | ||
588 | if (!tr->allocated_snapshot) { | |
589 | ||
590 | /* allocate spare buffer */ | |
591 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
592 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
593 | if (ret < 0) | |
594 | return ret; | |
595 | ||
596 | tr->allocated_snapshot = true; | |
597 | } | |
598 | ||
599 | return 0; | |
600 | } | |
601 | ||
ad1438a0 | 602 | static void free_snapshot(struct trace_array *tr) |
3209cff4 SRRH |
603 | { |
604 | /* | |
605 | * We don't free the ring buffer. instead, resize it because | |
606 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
607 | * we want preserve it. | |
608 | */ | |
609 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
610 | set_buffer_entries(&tr->max_buffer, 1); | |
611 | tracing_reset_online_cpus(&tr->max_buffer); | |
612 | tr->allocated_snapshot = false; | |
613 | } | |
ad909e21 | 614 | |
93e31ffb TZ |
615 | /** |
616 | * tracing_alloc_snapshot - allocate snapshot buffer. | |
617 | * | |
618 | * This only allocates the snapshot buffer if it isn't already | |
619 | * allocated - it doesn't also take a snapshot. | |
620 | * | |
621 | * This is meant to be used in cases where the snapshot buffer needs | |
622 | * to be set up for events that can't sleep but need to be able to | |
623 | * trigger a snapshot. | |
624 | */ | |
625 | int tracing_alloc_snapshot(void) | |
626 | { | |
627 | struct trace_array *tr = &global_trace; | |
628 | int ret; | |
629 | ||
630 | ret = alloc_snapshot(tr); | |
631 | WARN_ON(ret < 0); | |
632 | ||
633 | return ret; | |
634 | } | |
635 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
636 | ||
ad909e21 SRRH |
637 | /** |
638 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
639 | * | |
640 | * This is similar to trace_snapshot(), but it will allocate the | |
641 | * snapshot buffer if it isn't already allocated. Use this only | |
642 | * where it is safe to sleep, as the allocation may sleep. | |
643 | * | |
644 | * This causes a swap between the snapshot buffer and the current live | |
645 | * tracing buffer. You can use this to take snapshots of the live | |
646 | * trace when some condition is triggered, but continue to trace. | |
647 | */ | |
648 | void tracing_snapshot_alloc(void) | |
649 | { | |
ad909e21 SRRH |
650 | int ret; |
651 | ||
93e31ffb TZ |
652 | ret = tracing_alloc_snapshot(); |
653 | if (ret < 0) | |
3209cff4 | 654 | return; |
ad909e21 SRRH |
655 | |
656 | tracing_snapshot(); | |
657 | } | |
1b22e382 | 658 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
659 | #else |
660 | void tracing_snapshot(void) | |
661 | { | |
662 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
663 | } | |
1b22e382 | 664 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
93e31ffb TZ |
665 | int tracing_alloc_snapshot(void) |
666 | { | |
667 | WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); | |
668 | return -ENODEV; | |
669 | } | |
670 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
ad909e21 SRRH |
671 | void tracing_snapshot_alloc(void) |
672 | { | |
673 | /* Give warning */ | |
674 | tracing_snapshot(); | |
675 | } | |
1b22e382 | 676 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
677 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
678 | ||
5280bcef | 679 | static void tracer_tracing_off(struct trace_array *tr) |
10246fa3 SRRH |
680 | { |
681 | if (tr->trace_buffer.buffer) | |
682 | ring_buffer_record_off(tr->trace_buffer.buffer); | |
683 | /* | |
684 | * This flag is looked at when buffers haven't been allocated | |
685 | * yet, or by some tracers (like irqsoff), that just want to | |
686 | * know if the ring buffer has been disabled, but it can handle | |
687 | * races of where it gets disabled but we still do a record. | |
688 | * As the check is in the fast path of the tracers, it is more | |
689 | * important to be fast than accurate. | |
690 | */ | |
691 | tr->buffer_disabled = 1; | |
692 | /* Make the flag seen by readers */ | |
693 | smp_wmb(); | |
694 | } | |
695 | ||
499e5470 SR |
696 | /** |
697 | * tracing_off - turn off tracing buffers | |
698 | * | |
699 | * This function stops the tracing buffers from recording data. | |
700 | * It does not disable any overhead the tracers themselves may | |
701 | * be causing. This function simply causes all recording to | |
702 | * the ring buffers to fail. | |
703 | */ | |
704 | void tracing_off(void) | |
705 | { | |
10246fa3 | 706 | tracer_tracing_off(&global_trace); |
499e5470 SR |
707 | } |
708 | EXPORT_SYMBOL_GPL(tracing_off); | |
709 | ||
de7edd31 SRRH |
710 | void disable_trace_on_warning(void) |
711 | { | |
712 | if (__disable_trace_on_warning) | |
713 | tracing_off(); | |
714 | } | |
715 | ||
10246fa3 SRRH |
716 | /** |
717 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
718 | * @tr : the trace array to know if ring buffer is enabled | |
719 | * | |
720 | * Shows real state of the ring buffer if it is enabled or not. | |
721 | */ | |
5280bcef | 722 | static int tracer_tracing_is_on(struct trace_array *tr) |
10246fa3 SRRH |
723 | { |
724 | if (tr->trace_buffer.buffer) | |
725 | return ring_buffer_record_is_on(tr->trace_buffer.buffer); | |
726 | return !tr->buffer_disabled; | |
727 | } | |
728 | ||
499e5470 SR |
729 | /** |
730 | * tracing_is_on - show state of ring buffers enabled | |
731 | */ | |
732 | int tracing_is_on(void) | |
733 | { | |
10246fa3 | 734 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
735 | } |
736 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
737 | ||
3928a8a2 | 738 | static int __init set_buf_size(char *str) |
bc0c38d1 | 739 | { |
3928a8a2 | 740 | unsigned long buf_size; |
c6caeeb1 | 741 | |
bc0c38d1 SR |
742 | if (!str) |
743 | return 0; | |
9d612bef | 744 | buf_size = memparse(str, &str); |
c6caeeb1 | 745 | /* nr_entries can not be zero */ |
9d612bef | 746 | if (buf_size == 0) |
c6caeeb1 | 747 | return 0; |
3928a8a2 | 748 | trace_buf_size = buf_size; |
bc0c38d1 SR |
749 | return 1; |
750 | } | |
3928a8a2 | 751 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 752 | |
0e950173 TB |
753 | static int __init set_tracing_thresh(char *str) |
754 | { | |
87abb3b1 | 755 | unsigned long threshold; |
0e950173 TB |
756 | int ret; |
757 | ||
758 | if (!str) | |
759 | return 0; | |
bcd83ea6 | 760 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
761 | if (ret < 0) |
762 | return 0; | |
87abb3b1 | 763 | tracing_thresh = threshold * 1000; |
0e950173 TB |
764 | return 1; |
765 | } | |
766 | __setup("tracing_thresh=", set_tracing_thresh); | |
767 | ||
57f50be1 SR |
768 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
769 | { | |
770 | return nsecs / 1000; | |
771 | } | |
772 | ||
4fcdae83 | 773 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
774 | static const char *trace_options[] = { |
775 | "print-parent", | |
776 | "sym-offset", | |
777 | "sym-addr", | |
778 | "verbose", | |
f9896bf3 | 779 | "raw", |
5e3ca0ec | 780 | "hex", |
cb0f12aa | 781 | "bin", |
2a2cc8f7 | 782 | "block", |
86387f7e | 783 | "stacktrace", |
5e1607a0 | 784 | "trace_printk", |
b2a866f9 | 785 | "ftrace_preempt", |
9f029e83 | 786 | "branch", |
12ef7d44 | 787 | "annotate", |
02b67518 | 788 | "userstacktrace", |
b54d3de9 | 789 | "sym-userobj", |
66896a85 | 790 | "printk-msg-only", |
c4a8e8be | 791 | "context-info", |
c032ef64 | 792 | "latency-format", |
be6f164a | 793 | "sleep-time", |
a2a16d6a | 794 | "graph-time", |
e870e9a1 | 795 | "record-cmd", |
750912fa | 796 | "overwrite", |
cf30cf67 | 797 | "disable_on_free", |
77271ce4 | 798 | "irq-info", |
5224c3a3 | 799 | "markers", |
328df475 | 800 | "function-trace", |
bc0c38d1 SR |
801 | NULL |
802 | }; | |
803 | ||
5079f326 Z |
804 | static struct { |
805 | u64 (*func)(void); | |
806 | const char *name; | |
8be0709f | 807 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 808 | } trace_clocks[] = { |
8be0709f DS |
809 | { trace_clock_local, "local", 1 }, |
810 | { trace_clock_global, "global", 1 }, | |
811 | { trace_clock_counter, "counter", 0 }, | |
8aacf017 | 812 | { trace_clock_jiffies, "uptime", 1 }, |
76f11917 | 813 | { trace_clock, "perf", 1 }, |
8cbd9cc6 | 814 | ARCH_TRACE_CLOCKS |
5079f326 Z |
815 | }; |
816 | ||
b63f39ea | 817 | /* |
818 | * trace_parser_get_init - gets the buffer for trace parser | |
819 | */ | |
820 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
821 | { | |
822 | memset(parser, 0, sizeof(*parser)); | |
823 | ||
824 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
825 | if (!parser->buffer) | |
826 | return 1; | |
827 | ||
828 | parser->size = size; | |
829 | return 0; | |
830 | } | |
831 | ||
832 | /* | |
833 | * trace_parser_put - frees the buffer for trace parser | |
834 | */ | |
835 | void trace_parser_put(struct trace_parser *parser) | |
836 | { | |
837 | kfree(parser->buffer); | |
838 | } | |
839 | ||
840 | /* | |
841 | * trace_get_user - reads the user input string separated by space | |
842 | * (matched by isspace(ch)) | |
843 | * | |
844 | * For each string found the 'struct trace_parser' is updated, | |
845 | * and the function returns. | |
846 | * | |
847 | * Returns number of bytes read. | |
848 | * | |
849 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
850 | */ | |
851 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
852 | size_t cnt, loff_t *ppos) | |
853 | { | |
854 | char ch; | |
855 | size_t read = 0; | |
856 | ssize_t ret; | |
857 | ||
858 | if (!*ppos) | |
859 | trace_parser_clear(parser); | |
860 | ||
861 | ret = get_user(ch, ubuf++); | |
862 | if (ret) | |
863 | goto out; | |
864 | ||
865 | read++; | |
866 | cnt--; | |
867 | ||
868 | /* | |
869 | * The parser is not finished with the last write, | |
870 | * continue reading the user input without skipping spaces. | |
871 | */ | |
872 | if (!parser->cont) { | |
873 | /* skip white space */ | |
874 | while (cnt && isspace(ch)) { | |
875 | ret = get_user(ch, ubuf++); | |
876 | if (ret) | |
877 | goto out; | |
878 | read++; | |
879 | cnt--; | |
880 | } | |
881 | ||
882 | /* only spaces were written */ | |
883 | if (isspace(ch)) { | |
884 | *ppos += read; | |
885 | ret = read; | |
886 | goto out; | |
887 | } | |
888 | ||
889 | parser->idx = 0; | |
890 | } | |
891 | ||
892 | /* read the non-space input */ | |
893 | while (cnt && !isspace(ch)) { | |
3c235a33 | 894 | if (parser->idx < parser->size - 1) |
b63f39ea | 895 | parser->buffer[parser->idx++] = ch; |
896 | else { | |
897 | ret = -EINVAL; | |
898 | goto out; | |
899 | } | |
900 | ret = get_user(ch, ubuf++); | |
901 | if (ret) | |
902 | goto out; | |
903 | read++; | |
904 | cnt--; | |
905 | } | |
906 | ||
907 | /* We either got finished input or we have to wait for another call. */ | |
908 | if (isspace(ch)) { | |
909 | parser->buffer[parser->idx] = 0; | |
910 | parser->cont = false; | |
057db848 | 911 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 912 | parser->cont = true; |
913 | parser->buffer[parser->idx++] = ch; | |
057db848 SR |
914 | } else { |
915 | ret = -EINVAL; | |
916 | goto out; | |
b63f39ea | 917 | } |
918 | ||
919 | *ppos += read; | |
920 | ret = read; | |
921 | ||
922 | out: | |
923 | return ret; | |
924 | } | |
925 | ||
b8b94265 | 926 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
927 | { |
928 | int len; | |
3c56819b EGM |
929 | |
930 | if (s->len <= s->readpos) | |
931 | return -EBUSY; | |
932 | ||
933 | len = s->len - s->readpos; | |
934 | if (cnt > len) | |
935 | cnt = len; | |
5a26c8f0 | 936 | memcpy(buf, s->buffer + s->readpos, cnt); |
3c56819b | 937 | |
e74da523 | 938 | s->readpos += cnt; |
3c56819b EGM |
939 | return cnt; |
940 | } | |
941 | ||
0e950173 TB |
942 | unsigned long __read_mostly tracing_thresh; |
943 | ||
5d4a9dba | 944 | #ifdef CONFIG_TRACER_MAX_TRACE |
5d4a9dba SR |
945 | /* |
946 | * Copy the new maximum trace into the separate maximum-trace | |
947 | * structure. (this way the maximum trace is permanently saved, | |
948 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
949 | */ | |
950 | static void | |
951 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
952 | { | |
12883efb SRRH |
953 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
954 | struct trace_buffer *max_buf = &tr->max_buffer; | |
955 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
956 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 957 | |
12883efb SRRH |
958 | max_buf->cpu = cpu; |
959 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 960 | |
6d9b3fa5 | 961 | max_data->saved_latency = tr->max_latency; |
8248ac05 SR |
962 | max_data->critical_start = data->critical_start; |
963 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 964 | |
1acaa1b2 | 965 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 966 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
967 | /* |
968 | * If tsk == current, then use current_uid(), as that does not use | |
969 | * RCU. The irq tracer can be called out of RCU scope. | |
970 | */ | |
971 | if (tsk == current) | |
972 | max_data->uid = current_uid(); | |
973 | else | |
974 | max_data->uid = task_uid(tsk); | |
975 | ||
8248ac05 SR |
976 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
977 | max_data->policy = tsk->policy; | |
978 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
979 | |
980 | /* record this tasks comm */ | |
981 | tracing_record_cmdline(tsk); | |
982 | } | |
983 | ||
4fcdae83 SR |
984 | /** |
985 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
986 | * @tr: tracer | |
987 | * @tsk: the task with the latency | |
988 | * @cpu: The cpu that initiated the trace. | |
989 | * | |
990 | * Flip the buffers between the @tr and the max_tr and record information | |
991 | * about which task was the cause of this latency. | |
992 | */ | |
e309b41d | 993 | void |
bc0c38d1 SR |
994 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
995 | { | |
2721e72d | 996 | struct ring_buffer *buf; |
bc0c38d1 | 997 | |
2b6080f2 | 998 | if (tr->stop_count) |
b8de7bd1 SR |
999 | return; |
1000 | ||
4c11d7ae | 1001 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 1002 | |
45ad21ca | 1003 | if (!tr->allocated_snapshot) { |
debdd57f | 1004 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 1005 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 1006 | return; |
debdd57f | 1007 | } |
34600f0e | 1008 | |
0b9b12c1 | 1009 | arch_spin_lock(&tr->max_lock); |
3928a8a2 | 1010 | |
12883efb SRRH |
1011 | buf = tr->trace_buffer.buffer; |
1012 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
1013 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 1014 | |
bc0c38d1 | 1015 | __update_max_tr(tr, tsk, cpu); |
0b9b12c1 | 1016 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 SR |
1017 | } |
1018 | ||
1019 | /** | |
1020 | * update_max_tr_single - only copy one trace over, and reset the rest | |
1021 | * @tr - tracer | |
1022 | * @tsk - task with the latency | |
1023 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
1024 | * |
1025 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1026 | */ |
e309b41d | 1027 | void |
bc0c38d1 SR |
1028 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1029 | { | |
3928a8a2 | 1030 | int ret; |
bc0c38d1 | 1031 | |
2b6080f2 | 1032 | if (tr->stop_count) |
b8de7bd1 SR |
1033 | return; |
1034 | ||
4c11d7ae | 1035 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1036 | if (!tr->allocated_snapshot) { |
2930e04d | 1037 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1038 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1039 | return; |
2930e04d | 1040 | } |
ef710e10 | 1041 | |
0b9b12c1 | 1042 | arch_spin_lock(&tr->max_lock); |
bc0c38d1 | 1043 | |
12883efb | 1044 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 1045 | |
e8165dbb SR |
1046 | if (ret == -EBUSY) { |
1047 | /* | |
1048 | * We failed to swap the buffer due to a commit taking | |
1049 | * place on this CPU. We fail to record, but we reset | |
1050 | * the max trace buffer (no one writes directly to it) | |
1051 | * and flag that it failed. | |
1052 | */ | |
12883efb | 1053 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1054 | "Failed to swap buffers due to commit in progress\n"); |
1055 | } | |
1056 | ||
e8165dbb | 1057 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1058 | |
1059 | __update_max_tr(tr, tsk, cpu); | |
0b9b12c1 | 1060 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 | 1061 | } |
5d4a9dba | 1062 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1063 | |
8b8b3683 | 1064 | static int wait_on_pipe(struct trace_iterator *iter) |
0d5c6e1c | 1065 | { |
15693458 SRRH |
1066 | /* Iterators are static, they should be filled or empty */ |
1067 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
8b8b3683 | 1068 | return 0; |
0d5c6e1c | 1069 | |
8b8b3683 | 1070 | return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file); |
0d5c6e1c SR |
1071 | } |
1072 | ||
f4e781c0 SRRH |
1073 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
1074 | static int run_tracer_selftest(struct tracer *type) | |
1075 | { | |
1076 | struct trace_array *tr = &global_trace; | |
1077 | struct tracer *saved_tracer = tr->current_trace; | |
1078 | int ret; | |
0d5c6e1c | 1079 | |
f4e781c0 SRRH |
1080 | if (!type->selftest || tracing_selftest_disabled) |
1081 | return 0; | |
0d5c6e1c SR |
1082 | |
1083 | /* | |
f4e781c0 SRRH |
1084 | * Run a selftest on this tracer. |
1085 | * Here we reset the trace buffer, and set the current | |
1086 | * tracer to be this tracer. The tracer can then run some | |
1087 | * internal tracing to verify that everything is in order. | |
1088 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1089 | */ |
f4e781c0 | 1090 | tracing_reset_online_cpus(&tr->trace_buffer); |
0d5c6e1c | 1091 | |
f4e781c0 SRRH |
1092 | tr->current_trace = type; |
1093 | ||
1094 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1095 | if (type->use_max_tr) { | |
1096 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1097 | if (ring_buffer_expanded) | |
1098 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1099 | RING_BUFFER_ALL_CPUS); | |
1100 | tr->allocated_snapshot = true; | |
1101 | } | |
1102 | #endif | |
1103 | ||
1104 | /* the test is responsible for initializing and enabling */ | |
1105 | pr_info("Testing tracer %s: ", type->name); | |
1106 | ret = type->selftest(type, tr); | |
1107 | /* the test is responsible for resetting too */ | |
1108 | tr->current_trace = saved_tracer; | |
1109 | if (ret) { | |
1110 | printk(KERN_CONT "FAILED!\n"); | |
1111 | /* Add the warning after printing 'FAILED' */ | |
1112 | WARN_ON(1); | |
1113 | return -1; | |
1114 | } | |
1115 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1116 | tracing_reset_online_cpus(&tr->trace_buffer); | |
1117 | ||
1118 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1119 | if (type->use_max_tr) { | |
1120 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1121 | |
f4e781c0 SRRH |
1122 | /* Shrink the max buffer again */ |
1123 | if (ring_buffer_expanded) | |
1124 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1125 | RING_BUFFER_ALL_CPUS); | |
1126 | } | |
1127 | #endif | |
1128 | ||
1129 | printk(KERN_CONT "PASSED\n"); | |
1130 | return 0; | |
1131 | } | |
1132 | #else | |
1133 | static inline int run_tracer_selftest(struct tracer *type) | |
1134 | { | |
1135 | return 0; | |
0d5c6e1c | 1136 | } |
f4e781c0 | 1137 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 1138 | |
4fcdae83 SR |
1139 | /** |
1140 | * register_tracer - register a tracer with the ftrace system. | |
1141 | * @type - the plugin for the tracer | |
1142 | * | |
1143 | * Register a new plugin tracer. | |
1144 | */ | |
bc0c38d1 SR |
1145 | int register_tracer(struct tracer *type) |
1146 | { | |
1147 | struct tracer *t; | |
bc0c38d1 SR |
1148 | int ret = 0; |
1149 | ||
1150 | if (!type->name) { | |
1151 | pr_info("Tracer must have a name\n"); | |
1152 | return -1; | |
1153 | } | |
1154 | ||
24a461d5 | 1155 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
1156 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
1157 | return -1; | |
1158 | } | |
1159 | ||
bc0c38d1 | 1160 | mutex_lock(&trace_types_lock); |
86fa2f60 | 1161 | |
8e1b82e0 FW |
1162 | tracing_selftest_running = true; |
1163 | ||
bc0c38d1 SR |
1164 | for (t = trace_types; t; t = t->next) { |
1165 | if (strcmp(type->name, t->name) == 0) { | |
1166 | /* already found */ | |
ee6c2c1b | 1167 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
1168 | type->name); |
1169 | ret = -1; | |
1170 | goto out; | |
1171 | } | |
1172 | } | |
1173 | ||
adf9f195 FW |
1174 | if (!type->set_flag) |
1175 | type->set_flag = &dummy_set_flag; | |
1176 | if (!type->flags) | |
1177 | type->flags = &dummy_tracer_flags; | |
1178 | else | |
1179 | if (!type->flags->opts) | |
1180 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 | 1181 | |
f4e781c0 SRRH |
1182 | ret = run_tracer_selftest(type); |
1183 | if (ret < 0) | |
1184 | goto out; | |
60a11774 | 1185 | |
bc0c38d1 SR |
1186 | type->next = trace_types; |
1187 | trace_types = type; | |
60a11774 | 1188 | |
bc0c38d1 | 1189 | out: |
8e1b82e0 | 1190 | tracing_selftest_running = false; |
bc0c38d1 SR |
1191 | mutex_unlock(&trace_types_lock); |
1192 | ||
dac74940 SR |
1193 | if (ret || !default_bootup_tracer) |
1194 | goto out_unlock; | |
1195 | ||
ee6c2c1b | 1196 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1197 | goto out_unlock; |
1198 | ||
1199 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1200 | /* Do we want this tracer to start on bootup? */ | |
607e2ea1 | 1201 | tracing_set_tracer(&global_trace, type->name); |
dac74940 SR |
1202 | default_bootup_tracer = NULL; |
1203 | /* disable other selftests, since this will break it. */ | |
55034cd6 | 1204 | tracing_selftest_disabled = true; |
b2821ae6 | 1205 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1206 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1207 | type->name); | |
b2821ae6 | 1208 | #endif |
b2821ae6 | 1209 | |
dac74940 | 1210 | out_unlock: |
bc0c38d1 SR |
1211 | return ret; |
1212 | } | |
1213 | ||
12883efb | 1214 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1215 | { |
12883efb | 1216 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1217 | |
a5416411 HT |
1218 | if (!buffer) |
1219 | return; | |
1220 | ||
f633903a SR |
1221 | ring_buffer_record_disable(buffer); |
1222 | ||
1223 | /* Make sure all commits have finished */ | |
1224 | synchronize_sched(); | |
68179686 | 1225 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1226 | |
1227 | ring_buffer_record_enable(buffer); | |
1228 | } | |
1229 | ||
12883efb | 1230 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1231 | { |
12883efb | 1232 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1233 | int cpu; |
1234 | ||
a5416411 HT |
1235 | if (!buffer) |
1236 | return; | |
1237 | ||
621968cd SR |
1238 | ring_buffer_record_disable(buffer); |
1239 | ||
1240 | /* Make sure all commits have finished */ | |
1241 | synchronize_sched(); | |
1242 | ||
9457158b | 1243 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 PE |
1244 | |
1245 | for_each_online_cpu(cpu) | |
68179686 | 1246 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1247 | |
1248 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1249 | } |
1250 | ||
09d8091c | 1251 | /* Must have trace_types_lock held */ |
873c642f | 1252 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1253 | { |
873c642f SRRH |
1254 | struct trace_array *tr; |
1255 | ||
873c642f | 1256 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
12883efb SRRH |
1257 | tracing_reset_online_cpus(&tr->trace_buffer); |
1258 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1259 | tracing_reset_online_cpus(&tr->max_buffer); | |
1260 | #endif | |
873c642f | 1261 | } |
9456f0fa SR |
1262 | } |
1263 | ||
939c7a4f | 1264 | #define SAVED_CMDLINES_DEFAULT 128 |
2c7eea4c | 1265 | #define NO_CMDLINE_MAP UINT_MAX |
edc35bd7 | 1266 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
939c7a4f YY |
1267 | struct saved_cmdlines_buffer { |
1268 | unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
1269 | unsigned *map_cmdline_to_pid; | |
1270 | unsigned cmdline_num; | |
1271 | int cmdline_idx; | |
1272 | char *saved_cmdlines; | |
1273 | }; | |
1274 | static struct saved_cmdlines_buffer *savedcmd; | |
25b0b44a | 1275 | |
25b0b44a | 1276 | /* temporary disable recording */ |
4fd27358 | 1277 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 | 1278 | |
939c7a4f YY |
1279 | static inline char *get_saved_cmdlines(int idx) |
1280 | { | |
1281 | return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN]; | |
1282 | } | |
1283 | ||
1284 | static inline void set_cmdline(int idx, const char *cmdline) | |
bc0c38d1 | 1285 | { |
939c7a4f YY |
1286 | memcpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); |
1287 | } | |
1288 | ||
1289 | static int allocate_cmdlines_buffer(unsigned int val, | |
1290 | struct saved_cmdlines_buffer *s) | |
1291 | { | |
1292 | s->map_cmdline_to_pid = kmalloc(val * sizeof(*s->map_cmdline_to_pid), | |
1293 | GFP_KERNEL); | |
1294 | if (!s->map_cmdline_to_pid) | |
1295 | return -ENOMEM; | |
1296 | ||
1297 | s->saved_cmdlines = kmalloc(val * TASK_COMM_LEN, GFP_KERNEL); | |
1298 | if (!s->saved_cmdlines) { | |
1299 | kfree(s->map_cmdline_to_pid); | |
1300 | return -ENOMEM; | |
1301 | } | |
1302 | ||
1303 | s->cmdline_idx = 0; | |
1304 | s->cmdline_num = val; | |
1305 | memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP, | |
1306 | sizeof(s->map_pid_to_cmdline)); | |
1307 | memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP, | |
1308 | val * sizeof(*s->map_cmdline_to_pid)); | |
1309 | ||
1310 | return 0; | |
1311 | } | |
1312 | ||
1313 | static int trace_create_savedcmd(void) | |
1314 | { | |
1315 | int ret; | |
1316 | ||
a6af8fbf | 1317 | savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL); |
939c7a4f YY |
1318 | if (!savedcmd) |
1319 | return -ENOMEM; | |
1320 | ||
1321 | ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd); | |
1322 | if (ret < 0) { | |
1323 | kfree(savedcmd); | |
1324 | savedcmd = NULL; | |
1325 | return -ENOMEM; | |
1326 | } | |
1327 | ||
1328 | return 0; | |
bc0c38d1 SR |
1329 | } |
1330 | ||
b5130b1e CE |
1331 | int is_tracing_stopped(void) |
1332 | { | |
2b6080f2 | 1333 | return global_trace.stop_count; |
b5130b1e CE |
1334 | } |
1335 | ||
0f048701 SR |
1336 | /** |
1337 | * tracing_start - quick start of the tracer | |
1338 | * | |
1339 | * If tracing is enabled but was stopped by tracing_stop, | |
1340 | * this will start the tracer back up. | |
1341 | */ | |
1342 | void tracing_start(void) | |
1343 | { | |
1344 | struct ring_buffer *buffer; | |
1345 | unsigned long flags; | |
1346 | ||
1347 | if (tracing_disabled) | |
1348 | return; | |
1349 | ||
2b6080f2 SR |
1350 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1351 | if (--global_trace.stop_count) { | |
1352 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1353 | /* Someone screwed up their debugging */ |
1354 | WARN_ON_ONCE(1); | |
2b6080f2 | 1355 | global_trace.stop_count = 0; |
b06a8301 | 1356 | } |
0f048701 SR |
1357 | goto out; |
1358 | } | |
1359 | ||
a2f80714 | 1360 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1361 | arch_spin_lock(&global_trace.max_lock); |
0f048701 | 1362 | |
12883efb | 1363 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1364 | if (buffer) |
1365 | ring_buffer_record_enable(buffer); | |
1366 | ||
12883efb SRRH |
1367 | #ifdef CONFIG_TRACER_MAX_TRACE |
1368 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1369 | if (buffer) |
1370 | ring_buffer_record_enable(buffer); | |
12883efb | 1371 | #endif |
0f048701 | 1372 | |
0b9b12c1 | 1373 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1374 | |
0f048701 SR |
1375 | ftrace_start(); |
1376 | out: | |
2b6080f2 SR |
1377 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1378 | } | |
1379 | ||
1380 | static void tracing_start_tr(struct trace_array *tr) | |
1381 | { | |
1382 | struct ring_buffer *buffer; | |
1383 | unsigned long flags; | |
1384 | ||
1385 | if (tracing_disabled) | |
1386 | return; | |
1387 | ||
1388 | /* If global, we need to also start the max tracer */ | |
1389 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1390 | return tracing_start(); | |
1391 | ||
1392 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1393 | ||
1394 | if (--tr->stop_count) { | |
1395 | if (tr->stop_count < 0) { | |
1396 | /* Someone screwed up their debugging */ | |
1397 | WARN_ON_ONCE(1); | |
1398 | tr->stop_count = 0; | |
1399 | } | |
1400 | goto out; | |
1401 | } | |
1402 | ||
12883efb | 1403 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1404 | if (buffer) |
1405 | ring_buffer_record_enable(buffer); | |
1406 | ||
1407 | out: | |
1408 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1409 | } |
1410 | ||
1411 | /** | |
1412 | * tracing_stop - quick stop of the tracer | |
1413 | * | |
1414 | * Light weight way to stop tracing. Use in conjunction with | |
1415 | * tracing_start. | |
1416 | */ | |
1417 | void tracing_stop(void) | |
1418 | { | |
1419 | struct ring_buffer *buffer; | |
1420 | unsigned long flags; | |
1421 | ||
1422 | ftrace_stop(); | |
2b6080f2 SR |
1423 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1424 | if (global_trace.stop_count++) | |
0f048701 SR |
1425 | goto out; |
1426 | ||
a2f80714 | 1427 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1428 | arch_spin_lock(&global_trace.max_lock); |
a2f80714 | 1429 | |
12883efb | 1430 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1431 | if (buffer) |
1432 | ring_buffer_record_disable(buffer); | |
1433 | ||
12883efb SRRH |
1434 | #ifdef CONFIG_TRACER_MAX_TRACE |
1435 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1436 | if (buffer) |
1437 | ring_buffer_record_disable(buffer); | |
12883efb | 1438 | #endif |
0f048701 | 1439 | |
0b9b12c1 | 1440 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1441 | |
0f048701 | 1442 | out: |
2b6080f2 SR |
1443 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1444 | } | |
1445 | ||
1446 | static void tracing_stop_tr(struct trace_array *tr) | |
1447 | { | |
1448 | struct ring_buffer *buffer; | |
1449 | unsigned long flags; | |
1450 | ||
1451 | /* If global, we need to also stop the max tracer */ | |
1452 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1453 | return tracing_stop(); | |
1454 | ||
1455 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1456 | if (tr->stop_count++) | |
1457 | goto out; | |
1458 | ||
12883efb | 1459 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1460 | if (buffer) |
1461 | ring_buffer_record_disable(buffer); | |
1462 | ||
1463 | out: | |
1464 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1465 | } |
1466 | ||
e309b41d | 1467 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1468 | |
379cfdac | 1469 | static int trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1470 | { |
a635cf04 | 1471 | unsigned pid, idx; |
bc0c38d1 SR |
1472 | |
1473 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
379cfdac | 1474 | return 0; |
bc0c38d1 SR |
1475 | |
1476 | /* | |
1477 | * It's not the end of the world if we don't get | |
1478 | * the lock, but we also don't want to spin | |
1479 | * nor do we want to disable interrupts, | |
1480 | * so if we miss here, then better luck next time. | |
1481 | */ | |
0199c4e6 | 1482 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
379cfdac | 1483 | return 0; |
bc0c38d1 | 1484 | |
939c7a4f | 1485 | idx = savedcmd->map_pid_to_cmdline[tsk->pid]; |
2c7eea4c | 1486 | if (idx == NO_CMDLINE_MAP) { |
939c7a4f | 1487 | idx = (savedcmd->cmdline_idx + 1) % savedcmd->cmdline_num; |
bc0c38d1 | 1488 | |
a635cf04 CE |
1489 | /* |
1490 | * Check whether the cmdline buffer at idx has a pid | |
1491 | * mapped. We are going to overwrite that entry so we | |
1492 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1493 | * would read the new comm for the old pid. | |
1494 | */ | |
939c7a4f | 1495 | pid = savedcmd->map_cmdline_to_pid[idx]; |
a635cf04 | 1496 | if (pid != NO_CMDLINE_MAP) |
939c7a4f | 1497 | savedcmd->map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; |
bc0c38d1 | 1498 | |
939c7a4f YY |
1499 | savedcmd->map_cmdline_to_pid[idx] = tsk->pid; |
1500 | savedcmd->map_pid_to_cmdline[tsk->pid] = idx; | |
bc0c38d1 | 1501 | |
939c7a4f | 1502 | savedcmd->cmdline_idx = idx; |
bc0c38d1 SR |
1503 | } |
1504 | ||
939c7a4f | 1505 | set_cmdline(idx, tsk->comm); |
bc0c38d1 | 1506 | |
0199c4e6 | 1507 | arch_spin_unlock(&trace_cmdline_lock); |
379cfdac SRRH |
1508 | |
1509 | return 1; | |
bc0c38d1 SR |
1510 | } |
1511 | ||
4c27e756 | 1512 | static void __trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1513 | { |
bc0c38d1 SR |
1514 | unsigned map; |
1515 | ||
4ca53085 SR |
1516 | if (!pid) { |
1517 | strcpy(comm, "<idle>"); | |
1518 | return; | |
1519 | } | |
bc0c38d1 | 1520 | |
74bf4076 SR |
1521 | if (WARN_ON_ONCE(pid < 0)) { |
1522 | strcpy(comm, "<XXX>"); | |
1523 | return; | |
1524 | } | |
1525 | ||
4ca53085 SR |
1526 | if (pid > PID_MAX_DEFAULT) { |
1527 | strcpy(comm, "<...>"); | |
1528 | return; | |
1529 | } | |
bc0c38d1 | 1530 | |
939c7a4f | 1531 | map = savedcmd->map_pid_to_cmdline[pid]; |
50d88758 | 1532 | if (map != NO_CMDLINE_MAP) |
939c7a4f | 1533 | strcpy(comm, get_saved_cmdlines(map)); |
50d88758 TG |
1534 | else |
1535 | strcpy(comm, "<...>"); | |
4c27e756 SRRH |
1536 | } |
1537 | ||
1538 | void trace_find_cmdline(int pid, char comm[]) | |
1539 | { | |
1540 | preempt_disable(); | |
1541 | arch_spin_lock(&trace_cmdline_lock); | |
1542 | ||
1543 | __trace_find_cmdline(pid, comm); | |
bc0c38d1 | 1544 | |
0199c4e6 | 1545 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1546 | preempt_enable(); |
bc0c38d1 SR |
1547 | } |
1548 | ||
e309b41d | 1549 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1550 | { |
0fb9656d | 1551 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1552 | return; |
1553 | ||
7ffbd48d SR |
1554 | if (!__this_cpu_read(trace_cmdline_save)) |
1555 | return; | |
1556 | ||
379cfdac SRRH |
1557 | if (trace_save_cmdline(tsk)) |
1558 | __this_cpu_write(trace_cmdline_save, false); | |
bc0c38d1 SR |
1559 | } |
1560 | ||
45dcd8b8 | 1561 | void |
38697053 SR |
1562 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1563 | int pc) | |
bc0c38d1 SR |
1564 | { |
1565 | struct task_struct *tsk = current; | |
bc0c38d1 | 1566 | |
777e208d SR |
1567 | entry->preempt_count = pc & 0xff; |
1568 | entry->pid = (tsk) ? tsk->pid : 0; | |
1569 | entry->flags = | |
9244489a | 1570 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1571 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1572 | #else |
1573 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1574 | #endif | |
bc0c38d1 SR |
1575 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1576 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
e5137b50 PZ |
1577 | (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) | |
1578 | (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0); | |
bc0c38d1 | 1579 | } |
f413cdb8 | 1580 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1581 | |
e77405ad SR |
1582 | struct ring_buffer_event * |
1583 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1584 | int type, | |
1585 | unsigned long len, | |
1586 | unsigned long flags, int pc) | |
51a763dd ACM |
1587 | { |
1588 | struct ring_buffer_event *event; | |
1589 | ||
e77405ad | 1590 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1591 | if (event != NULL) { |
1592 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1593 | ||
1594 | tracing_generic_entry_update(ent, flags, pc); | |
1595 | ent->type = type; | |
1596 | } | |
1597 | ||
1598 | return event; | |
1599 | } | |
51a763dd | 1600 | |
7ffbd48d SR |
1601 | void |
1602 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1603 | { | |
1604 | __this_cpu_write(trace_cmdline_save, true); | |
1605 | ring_buffer_unlock_commit(buffer, event); | |
1606 | } | |
1607 | ||
e77405ad SR |
1608 | static inline void |
1609 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1610 | struct ring_buffer_event *event, | |
0d5c6e1c | 1611 | unsigned long flags, int pc) |
51a763dd | 1612 | { |
7ffbd48d | 1613 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1614 | |
e77405ad SR |
1615 | ftrace_trace_stack(buffer, flags, 6, pc); |
1616 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1617 | } |
1618 | ||
e77405ad SR |
1619 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1620 | struct ring_buffer_event *event, | |
1621 | unsigned long flags, int pc) | |
07edf712 | 1622 | { |
0d5c6e1c | 1623 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
51a763dd | 1624 | } |
0d5c6e1c | 1625 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1626 | |
2c4a33ab SRRH |
1627 | static struct ring_buffer *temp_buffer; |
1628 | ||
ccb469a1 SR |
1629 | struct ring_buffer_event * |
1630 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
1631 | struct ftrace_event_file *ftrace_file, | |
1632 | int type, unsigned long len, | |
1633 | unsigned long flags, int pc) | |
1634 | { | |
2c4a33ab SRRH |
1635 | struct ring_buffer_event *entry; |
1636 | ||
12883efb | 1637 | *current_rb = ftrace_file->tr->trace_buffer.buffer; |
2c4a33ab | 1638 | entry = trace_buffer_lock_reserve(*current_rb, |
ccb469a1 | 1639 | type, len, flags, pc); |
2c4a33ab SRRH |
1640 | /* |
1641 | * If tracing is off, but we have triggers enabled | |
1642 | * we still need to look at the event data. Use the temp_buffer | |
1643 | * to store the trace event for the tigger to use. It's recusive | |
1644 | * safe and will not be recorded anywhere. | |
1645 | */ | |
1646 | if (!entry && ftrace_file->flags & FTRACE_EVENT_FL_TRIGGER_COND) { | |
1647 | *current_rb = temp_buffer; | |
1648 | entry = trace_buffer_lock_reserve(*current_rb, | |
1649 | type, len, flags, pc); | |
1650 | } | |
1651 | return entry; | |
ccb469a1 SR |
1652 | } |
1653 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
1654 | ||
ef5580d0 | 1655 | struct ring_buffer_event * |
e77405ad SR |
1656 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1657 | int type, unsigned long len, | |
ef5580d0 SR |
1658 | unsigned long flags, int pc) |
1659 | { | |
12883efb | 1660 | *current_rb = global_trace.trace_buffer.buffer; |
e77405ad | 1661 | return trace_buffer_lock_reserve(*current_rb, |
ef5580d0 SR |
1662 | type, len, flags, pc); |
1663 | } | |
94487d6d | 1664 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1665 | |
e77405ad SR |
1666 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1667 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1668 | unsigned long flags, int pc) |
1669 | { | |
0d5c6e1c | 1670 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
07edf712 | 1671 | } |
94487d6d | 1672 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1673 | |
0d5c6e1c SR |
1674 | void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1675 | struct ring_buffer_event *event, | |
1676 | unsigned long flags, int pc, | |
1677 | struct pt_regs *regs) | |
1fd8df2c | 1678 | { |
7ffbd48d | 1679 | __buffer_unlock_commit(buffer, event); |
1fd8df2c MH |
1680 | |
1681 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1682 | ftrace_trace_userstack(buffer, flags, pc); | |
1683 | } | |
0d5c6e1c | 1684 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1685 | |
e77405ad SR |
1686 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1687 | struct ring_buffer_event *event) | |
77d9f465 | 1688 | { |
e77405ad | 1689 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1690 | } |
12acd473 | 1691 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1692 | |
e309b41d | 1693 | void |
7be42151 | 1694 | trace_function(struct trace_array *tr, |
38697053 SR |
1695 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1696 | int pc) | |
bc0c38d1 | 1697 | { |
e1112b4d | 1698 | struct ftrace_event_call *call = &event_function; |
12883efb | 1699 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 1700 | struct ring_buffer_event *event; |
777e208d | 1701 | struct ftrace_entry *entry; |
bc0c38d1 | 1702 | |
d769041f | 1703 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1704 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1705 | return; |
1706 | ||
e77405ad | 1707 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1708 | flags, pc); |
3928a8a2 SR |
1709 | if (!event) |
1710 | return; | |
1711 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1712 | entry->ip = ip; |
1713 | entry->parent_ip = parent_ip; | |
e1112b4d | 1714 | |
f306cc82 | 1715 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1716 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1717 | } |
1718 | ||
c0a0d0d3 | 1719 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1720 | |
1721 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1722 | struct ftrace_stack { | |
1723 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1724 | }; | |
1725 | ||
1726 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1727 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1728 | ||
e77405ad | 1729 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1730 | unsigned long flags, |
1fd8df2c | 1731 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1732 | { |
e1112b4d | 1733 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1734 | struct ring_buffer_event *event; |
777e208d | 1735 | struct stack_entry *entry; |
86387f7e | 1736 | struct stack_trace trace; |
4a9bd3f1 SR |
1737 | int use_stack; |
1738 | int size = FTRACE_STACK_ENTRIES; | |
1739 | ||
1740 | trace.nr_entries = 0; | |
1741 | trace.skip = skip; | |
1742 | ||
1743 | /* | |
1744 | * Since events can happen in NMIs there's no safe way to | |
1745 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1746 | * or NMI comes in, it will just have to use the default | |
1747 | * FTRACE_STACK_SIZE. | |
1748 | */ | |
1749 | preempt_disable_notrace(); | |
1750 | ||
82146529 | 1751 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
1752 | /* |
1753 | * We don't need any atomic variables, just a barrier. | |
1754 | * If an interrupt comes in, we don't care, because it would | |
1755 | * have exited and put the counter back to what we want. | |
1756 | * We just need a barrier to keep gcc from moving things | |
1757 | * around. | |
1758 | */ | |
1759 | barrier(); | |
1760 | if (use_stack == 1) { | |
bdffd893 | 1761 | trace.entries = this_cpu_ptr(ftrace_stack.calls); |
4a9bd3f1 SR |
1762 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; |
1763 | ||
1764 | if (regs) | |
1765 | save_stack_trace_regs(regs, &trace); | |
1766 | else | |
1767 | save_stack_trace(&trace); | |
1768 | ||
1769 | if (trace.nr_entries > size) | |
1770 | size = trace.nr_entries; | |
1771 | } else | |
1772 | /* From now on, use_stack is a boolean */ | |
1773 | use_stack = 0; | |
1774 | ||
1775 | size *= sizeof(unsigned long); | |
86387f7e | 1776 | |
e77405ad | 1777 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1778 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1779 | if (!event) |
4a9bd3f1 SR |
1780 | goto out; |
1781 | entry = ring_buffer_event_data(event); | |
86387f7e | 1782 | |
4a9bd3f1 SR |
1783 | memset(&entry->caller, 0, size); |
1784 | ||
1785 | if (use_stack) | |
1786 | memcpy(&entry->caller, trace.entries, | |
1787 | trace.nr_entries * sizeof(unsigned long)); | |
1788 | else { | |
1789 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1790 | trace.entries = entry->caller; | |
1791 | if (regs) | |
1792 | save_stack_trace_regs(regs, &trace); | |
1793 | else | |
1794 | save_stack_trace(&trace); | |
1795 | } | |
1796 | ||
1797 | entry->size = trace.nr_entries; | |
86387f7e | 1798 | |
f306cc82 | 1799 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1800 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1801 | |
1802 | out: | |
1803 | /* Again, don't let gcc optimize things here */ | |
1804 | barrier(); | |
82146529 | 1805 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
1806 | preempt_enable_notrace(); |
1807 | ||
f0a920d5 IM |
1808 | } |
1809 | ||
1fd8df2c MH |
1810 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1811 | int skip, int pc, struct pt_regs *regs) | |
1812 | { | |
1813 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1814 | return; | |
1815 | ||
1816 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1817 | } | |
1818 | ||
e77405ad SR |
1819 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1820 | int skip, int pc) | |
53614991 SR |
1821 | { |
1822 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1823 | return; | |
1824 | ||
1fd8df2c | 1825 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1826 | } |
1827 | ||
c0a0d0d3 FW |
1828 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1829 | int pc) | |
38697053 | 1830 | { |
12883efb | 1831 | __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); |
38697053 SR |
1832 | } |
1833 | ||
03889384 SR |
1834 | /** |
1835 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 1836 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 1837 | */ |
c142be8e | 1838 | void trace_dump_stack(int skip) |
03889384 SR |
1839 | { |
1840 | unsigned long flags; | |
1841 | ||
1842 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1843 | return; |
03889384 SR |
1844 | |
1845 | local_save_flags(flags); | |
1846 | ||
c142be8e SRRH |
1847 | /* |
1848 | * Skip 3 more, seems to get us at the caller of | |
1849 | * this function. | |
1850 | */ | |
1851 | skip += 3; | |
1852 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, | |
1853 | flags, skip, preempt_count(), NULL); | |
03889384 SR |
1854 | } |
1855 | ||
91e86e56 SR |
1856 | static DEFINE_PER_CPU(int, user_stack_count); |
1857 | ||
e77405ad SR |
1858 | void |
1859 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1860 | { |
e1112b4d | 1861 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1862 | struct ring_buffer_event *event; |
02b67518 TE |
1863 | struct userstack_entry *entry; |
1864 | struct stack_trace trace; | |
02b67518 TE |
1865 | |
1866 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1867 | return; | |
1868 | ||
b6345879 SR |
1869 | /* |
1870 | * NMIs can not handle page faults, even with fix ups. | |
1871 | * The save user stack can (and often does) fault. | |
1872 | */ | |
1873 | if (unlikely(in_nmi())) | |
1874 | return; | |
02b67518 | 1875 | |
91e86e56 SR |
1876 | /* |
1877 | * prevent recursion, since the user stack tracing may | |
1878 | * trigger other kernel events. | |
1879 | */ | |
1880 | preempt_disable(); | |
1881 | if (__this_cpu_read(user_stack_count)) | |
1882 | goto out; | |
1883 | ||
1884 | __this_cpu_inc(user_stack_count); | |
1885 | ||
e77405ad | 1886 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1887 | sizeof(*entry), flags, pc); |
02b67518 | 1888 | if (!event) |
1dbd1951 | 1889 | goto out_drop_count; |
02b67518 | 1890 | entry = ring_buffer_event_data(event); |
02b67518 | 1891 | |
48659d31 | 1892 | entry->tgid = current->tgid; |
02b67518 TE |
1893 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1894 | ||
1895 | trace.nr_entries = 0; | |
1896 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1897 | trace.skip = 0; | |
1898 | trace.entries = entry->caller; | |
1899 | ||
1900 | save_stack_trace_user(&trace); | |
f306cc82 | 1901 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1902 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1903 | |
1dbd1951 | 1904 | out_drop_count: |
91e86e56 | 1905 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1906 | out: |
1907 | preempt_enable(); | |
02b67518 TE |
1908 | } |
1909 | ||
4fd27358 HE |
1910 | #ifdef UNUSED |
1911 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1912 | { |
7be42151 | 1913 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1914 | } |
4fd27358 | 1915 | #endif /* UNUSED */ |
02b67518 | 1916 | |
c0a0d0d3 FW |
1917 | #endif /* CONFIG_STACKTRACE */ |
1918 | ||
07d777fe SR |
1919 | /* created for use with alloc_percpu */ |
1920 | struct trace_buffer_struct { | |
1921 | char buffer[TRACE_BUF_SIZE]; | |
1922 | }; | |
1923 | ||
1924 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1925 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1926 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1927 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1928 | ||
1929 | /* | |
1930 | * The buffer used is dependent on the context. There is a per cpu | |
1931 | * buffer for normal context, softirq contex, hard irq context and | |
1932 | * for NMI context. Thise allows for lockless recording. | |
1933 | * | |
1934 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1935 | */ | |
1936 | static char *get_trace_buf(void) | |
1937 | { | |
1938 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
1939 | |
1940 | /* | |
1941 | * If we have allocated per cpu buffers, then we do not | |
1942 | * need to do any locking. | |
1943 | */ | |
1944 | if (in_nmi()) | |
1945 | percpu_buffer = trace_percpu_nmi_buffer; | |
1946 | else if (in_irq()) | |
1947 | percpu_buffer = trace_percpu_irq_buffer; | |
1948 | else if (in_softirq()) | |
1949 | percpu_buffer = trace_percpu_sirq_buffer; | |
1950 | else | |
1951 | percpu_buffer = trace_percpu_buffer; | |
1952 | ||
1953 | if (!percpu_buffer) | |
1954 | return NULL; | |
1955 | ||
d8a0349c | 1956 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
1957 | } |
1958 | ||
1959 | static int alloc_percpu_trace_buffer(void) | |
1960 | { | |
1961 | struct trace_buffer_struct *buffers; | |
1962 | struct trace_buffer_struct *sirq_buffers; | |
1963 | struct trace_buffer_struct *irq_buffers; | |
1964 | struct trace_buffer_struct *nmi_buffers; | |
1965 | ||
1966 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1967 | if (!buffers) | |
1968 | goto err_warn; | |
1969 | ||
1970 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1971 | if (!sirq_buffers) | |
1972 | goto err_sirq; | |
1973 | ||
1974 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1975 | if (!irq_buffers) | |
1976 | goto err_irq; | |
1977 | ||
1978 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
1979 | if (!nmi_buffers) | |
1980 | goto err_nmi; | |
1981 | ||
1982 | trace_percpu_buffer = buffers; | |
1983 | trace_percpu_sirq_buffer = sirq_buffers; | |
1984 | trace_percpu_irq_buffer = irq_buffers; | |
1985 | trace_percpu_nmi_buffer = nmi_buffers; | |
1986 | ||
1987 | return 0; | |
1988 | ||
1989 | err_nmi: | |
1990 | free_percpu(irq_buffers); | |
1991 | err_irq: | |
1992 | free_percpu(sirq_buffers); | |
1993 | err_sirq: | |
1994 | free_percpu(buffers); | |
1995 | err_warn: | |
1996 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
1997 | return -ENOMEM; | |
1998 | } | |
1999 | ||
81698831 SR |
2000 | static int buffers_allocated; |
2001 | ||
07d777fe SR |
2002 | void trace_printk_init_buffers(void) |
2003 | { | |
07d777fe SR |
2004 | if (buffers_allocated) |
2005 | return; | |
2006 | ||
2007 | if (alloc_percpu_trace_buffer()) | |
2008 | return; | |
2009 | ||
2184db46 SR |
2010 | /* trace_printk() is for debug use only. Don't use it in production. */ |
2011 | ||
2012 | pr_warning("\n**********************************************************\n"); | |
2013 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
2014 | pr_warning("** **\n"); | |
2015 | pr_warning("** trace_printk() being used. Allocating extra memory. **\n"); | |
2016 | pr_warning("** **\n"); | |
2017 | pr_warning("** This means that this is a DEBUG kernel and it is **\n"); | |
2018 | pr_warning("** unsafe for produciton use. **\n"); | |
2019 | pr_warning("** **\n"); | |
2020 | pr_warning("** If you see this message and you are not debugging **\n"); | |
2021 | pr_warning("** the kernel, report this immediately to your vendor! **\n"); | |
2022 | pr_warning("** **\n"); | |
2023 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
2024 | pr_warning("**********************************************************\n"); | |
07d777fe | 2025 | |
b382ede6 SR |
2026 | /* Expand the buffers to set size */ |
2027 | tracing_update_buffers(); | |
2028 | ||
07d777fe | 2029 | buffers_allocated = 1; |
81698831 SR |
2030 | |
2031 | /* | |
2032 | * trace_printk_init_buffers() can be called by modules. | |
2033 | * If that happens, then we need to start cmdline recording | |
2034 | * directly here. If the global_trace.buffer is already | |
2035 | * allocated here, then this was called by module code. | |
2036 | */ | |
12883efb | 2037 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
2038 | tracing_start_cmdline_record(); |
2039 | } | |
2040 | ||
2041 | void trace_printk_start_comm(void) | |
2042 | { | |
2043 | /* Start tracing comms if trace printk is set */ | |
2044 | if (!buffers_allocated) | |
2045 | return; | |
2046 | tracing_start_cmdline_record(); | |
2047 | } | |
2048 | ||
2049 | static void trace_printk_start_stop_comm(int enabled) | |
2050 | { | |
2051 | if (!buffers_allocated) | |
2052 | return; | |
2053 | ||
2054 | if (enabled) | |
2055 | tracing_start_cmdline_record(); | |
2056 | else | |
2057 | tracing_stop_cmdline_record(); | |
07d777fe SR |
2058 | } |
2059 | ||
769b0441 | 2060 | /** |
48ead020 | 2061 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
2062 | * |
2063 | */ | |
40ce74f1 | 2064 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 2065 | { |
e1112b4d | 2066 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 2067 | struct ring_buffer_event *event; |
e77405ad | 2068 | struct ring_buffer *buffer; |
769b0441 | 2069 | struct trace_array *tr = &global_trace; |
48ead020 | 2070 | struct bprint_entry *entry; |
769b0441 | 2071 | unsigned long flags; |
07d777fe SR |
2072 | char *tbuffer; |
2073 | int len = 0, size, pc; | |
769b0441 FW |
2074 | |
2075 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
2076 | return 0; | |
2077 | ||
2078 | /* Don't pollute graph traces with trace_vprintk internals */ | |
2079 | pause_graph_tracing(); | |
2080 | ||
2081 | pc = preempt_count(); | |
5168ae50 | 2082 | preempt_disable_notrace(); |
769b0441 | 2083 | |
07d777fe SR |
2084 | tbuffer = get_trace_buf(); |
2085 | if (!tbuffer) { | |
2086 | len = 0; | |
769b0441 | 2087 | goto out; |
07d777fe | 2088 | } |
769b0441 | 2089 | |
07d777fe | 2090 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 2091 | |
07d777fe SR |
2092 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
2093 | goto out; | |
769b0441 | 2094 | |
07d777fe | 2095 | local_save_flags(flags); |
769b0441 | 2096 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 2097 | buffer = tr->trace_buffer.buffer; |
e77405ad SR |
2098 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
2099 | flags, pc); | |
769b0441 | 2100 | if (!event) |
07d777fe | 2101 | goto out; |
769b0441 FW |
2102 | entry = ring_buffer_event_data(event); |
2103 | entry->ip = ip; | |
769b0441 FW |
2104 | entry->fmt = fmt; |
2105 | ||
07d777fe | 2106 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
f306cc82 | 2107 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2108 | __buffer_unlock_commit(buffer, event); |
d931369b SR |
2109 | ftrace_trace_stack(buffer, flags, 6, pc); |
2110 | } | |
769b0441 | 2111 | |
769b0441 | 2112 | out: |
5168ae50 | 2113 | preempt_enable_notrace(); |
769b0441 FW |
2114 | unpause_graph_tracing(); |
2115 | ||
2116 | return len; | |
2117 | } | |
48ead020 FW |
2118 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
2119 | ||
12883efb SRRH |
2120 | static int |
2121 | __trace_array_vprintk(struct ring_buffer *buffer, | |
2122 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 2123 | { |
e1112b4d | 2124 | struct ftrace_event_call *call = &event_print; |
48ead020 | 2125 | struct ring_buffer_event *event; |
07d777fe | 2126 | int len = 0, size, pc; |
48ead020 | 2127 | struct print_entry *entry; |
07d777fe SR |
2128 | unsigned long flags; |
2129 | char *tbuffer; | |
48ead020 FW |
2130 | |
2131 | if (tracing_disabled || tracing_selftest_running) | |
2132 | return 0; | |
2133 | ||
07d777fe SR |
2134 | /* Don't pollute graph traces with trace_vprintk internals */ |
2135 | pause_graph_tracing(); | |
2136 | ||
48ead020 FW |
2137 | pc = preempt_count(); |
2138 | preempt_disable_notrace(); | |
48ead020 | 2139 | |
07d777fe SR |
2140 | |
2141 | tbuffer = get_trace_buf(); | |
2142 | if (!tbuffer) { | |
2143 | len = 0; | |
48ead020 | 2144 | goto out; |
07d777fe | 2145 | } |
48ead020 | 2146 | |
07d777fe SR |
2147 | len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
2148 | if (len > TRACE_BUF_SIZE) | |
2149 | goto out; | |
48ead020 | 2150 | |
07d777fe | 2151 | local_save_flags(flags); |
48ead020 | 2152 | size = sizeof(*entry) + len + 1; |
e77405ad | 2153 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
07d777fe | 2154 | flags, pc); |
48ead020 | 2155 | if (!event) |
07d777fe | 2156 | goto out; |
48ead020 | 2157 | entry = ring_buffer_event_data(event); |
c13d2f7c | 2158 | entry->ip = ip; |
48ead020 | 2159 | |
07d777fe | 2160 | memcpy(&entry->buf, tbuffer, len); |
c13d2f7c | 2161 | entry->buf[len] = '\0'; |
f306cc82 | 2162 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2163 | __buffer_unlock_commit(buffer, event); |
07d777fe | 2164 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 2165 | } |
48ead020 FW |
2166 | out: |
2167 | preempt_enable_notrace(); | |
07d777fe | 2168 | unpause_graph_tracing(); |
48ead020 FW |
2169 | |
2170 | return len; | |
2171 | } | |
659372d3 | 2172 | |
12883efb SRRH |
2173 | int trace_array_vprintk(struct trace_array *tr, |
2174 | unsigned long ip, const char *fmt, va_list args) | |
2175 | { | |
2176 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
2177 | } | |
2178 | ||
2179 | int trace_array_printk(struct trace_array *tr, | |
2180 | unsigned long ip, const char *fmt, ...) | |
2181 | { | |
2182 | int ret; | |
2183 | va_list ap; | |
2184 | ||
2185 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2186 | return 0; | |
2187 | ||
2188 | va_start(ap, fmt); | |
2189 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
2190 | va_end(ap); | |
2191 | return ret; | |
2192 | } | |
2193 | ||
2194 | int trace_array_printk_buf(struct ring_buffer *buffer, | |
2195 | unsigned long ip, const char *fmt, ...) | |
2196 | { | |
2197 | int ret; | |
2198 | va_list ap; | |
2199 | ||
2200 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2201 | return 0; | |
2202 | ||
2203 | va_start(ap, fmt); | |
2204 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
2205 | va_end(ap); | |
2206 | return ret; | |
2207 | } | |
2208 | ||
659372d3 SR |
2209 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
2210 | { | |
a813a159 | 2211 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 2212 | } |
769b0441 FW |
2213 | EXPORT_SYMBOL_GPL(trace_vprintk); |
2214 | ||
e2ac8ef5 | 2215 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 2216 | { |
6d158a81 SR |
2217 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
2218 | ||
5a90f577 | 2219 | iter->idx++; |
6d158a81 SR |
2220 | if (buf_iter) |
2221 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
2222 | } |
2223 | ||
e309b41d | 2224 | static struct trace_entry * |
bc21b478 SR |
2225 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
2226 | unsigned long *lost_events) | |
dd0e545f | 2227 | { |
3928a8a2 | 2228 | struct ring_buffer_event *event; |
6d158a81 | 2229 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 2230 | |
d769041f SR |
2231 | if (buf_iter) |
2232 | event = ring_buffer_iter_peek(buf_iter, ts); | |
2233 | else | |
12883efb | 2234 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 2235 | lost_events); |
d769041f | 2236 | |
4a9bd3f1 SR |
2237 | if (event) { |
2238 | iter->ent_size = ring_buffer_event_length(event); | |
2239 | return ring_buffer_event_data(event); | |
2240 | } | |
2241 | iter->ent_size = 0; | |
2242 | return NULL; | |
dd0e545f | 2243 | } |
d769041f | 2244 | |
dd0e545f | 2245 | static struct trace_entry * |
bc21b478 SR |
2246 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
2247 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 2248 | { |
12883efb | 2249 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 2250 | struct trace_entry *ent, *next = NULL; |
aa27497c | 2251 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 2252 | int cpu_file = iter->cpu_file; |
3928a8a2 | 2253 | u64 next_ts = 0, ts; |
bc0c38d1 | 2254 | int next_cpu = -1; |
12b5da34 | 2255 | int next_size = 0; |
bc0c38d1 SR |
2256 | int cpu; |
2257 | ||
b04cc6b1 FW |
2258 | /* |
2259 | * If we are in a per_cpu trace file, don't bother by iterating over | |
2260 | * all cpu and peek directly. | |
2261 | */ | |
ae3b5093 | 2262 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
2263 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
2264 | return NULL; | |
bc21b478 | 2265 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
2266 | if (ent_cpu) |
2267 | *ent_cpu = cpu_file; | |
2268 | ||
2269 | return ent; | |
2270 | } | |
2271 | ||
ab46428c | 2272 | for_each_tracing_cpu(cpu) { |
dd0e545f | 2273 | |
3928a8a2 SR |
2274 | if (ring_buffer_empty_cpu(buffer, cpu)) |
2275 | continue; | |
dd0e545f | 2276 | |
bc21b478 | 2277 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 2278 | |
cdd31cd2 IM |
2279 | /* |
2280 | * Pick the entry with the smallest timestamp: | |
2281 | */ | |
3928a8a2 | 2282 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
2283 | next = ent; |
2284 | next_cpu = cpu; | |
3928a8a2 | 2285 | next_ts = ts; |
bc21b478 | 2286 | next_lost = lost_events; |
12b5da34 | 2287 | next_size = iter->ent_size; |
bc0c38d1 SR |
2288 | } |
2289 | } | |
2290 | ||
12b5da34 SR |
2291 | iter->ent_size = next_size; |
2292 | ||
bc0c38d1 SR |
2293 | if (ent_cpu) |
2294 | *ent_cpu = next_cpu; | |
2295 | ||
3928a8a2 SR |
2296 | if (ent_ts) |
2297 | *ent_ts = next_ts; | |
2298 | ||
bc21b478 SR |
2299 | if (missing_events) |
2300 | *missing_events = next_lost; | |
2301 | ||
bc0c38d1 SR |
2302 | return next; |
2303 | } | |
2304 | ||
dd0e545f | 2305 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
2306 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
2307 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 2308 | { |
bc21b478 | 2309 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
2310 | } |
2311 | ||
2312 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 2313 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 2314 | { |
bc21b478 SR |
2315 | iter->ent = __find_next_entry(iter, &iter->cpu, |
2316 | &iter->lost_events, &iter->ts); | |
dd0e545f | 2317 | |
3928a8a2 | 2318 | if (iter->ent) |
e2ac8ef5 | 2319 | trace_iterator_increment(iter); |
dd0e545f | 2320 | |
3928a8a2 | 2321 | return iter->ent ? iter : NULL; |
b3806b43 | 2322 | } |
bc0c38d1 | 2323 | |
e309b41d | 2324 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 2325 | { |
12883efb | 2326 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 2327 | &iter->lost_events); |
bc0c38d1 SR |
2328 | } |
2329 | ||
e309b41d | 2330 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
2331 | { |
2332 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 2333 | int i = (int)*pos; |
4e3c3333 | 2334 | void *ent; |
bc0c38d1 | 2335 | |
a63ce5b3 SR |
2336 | WARN_ON_ONCE(iter->leftover); |
2337 | ||
bc0c38d1 SR |
2338 | (*pos)++; |
2339 | ||
2340 | /* can't go backwards */ | |
2341 | if (iter->idx > i) | |
2342 | return NULL; | |
2343 | ||
2344 | if (iter->idx < 0) | |
955b61e5 | 2345 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2346 | else |
2347 | ent = iter; | |
2348 | ||
2349 | while (ent && iter->idx < i) | |
955b61e5 | 2350 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2351 | |
2352 | iter->pos = *pos; | |
2353 | ||
bc0c38d1 SR |
2354 | return ent; |
2355 | } | |
2356 | ||
955b61e5 | 2357 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 2358 | { |
2f26ebd5 SR |
2359 | struct ring_buffer_event *event; |
2360 | struct ring_buffer_iter *buf_iter; | |
2361 | unsigned long entries = 0; | |
2362 | u64 ts; | |
2363 | ||
12883efb | 2364 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 2365 | |
6d158a81 SR |
2366 | buf_iter = trace_buffer_iter(iter, cpu); |
2367 | if (!buf_iter) | |
2f26ebd5 SR |
2368 | return; |
2369 | ||
2f26ebd5 SR |
2370 | ring_buffer_iter_reset(buf_iter); |
2371 | ||
2372 | /* | |
2373 | * We could have the case with the max latency tracers | |
2374 | * that a reset never took place on a cpu. This is evident | |
2375 | * by the timestamp being before the start of the buffer. | |
2376 | */ | |
2377 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 2378 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
2379 | break; |
2380 | entries++; | |
2381 | ring_buffer_read(buf_iter, NULL); | |
2382 | } | |
2383 | ||
12883efb | 2384 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2385 | } |
2386 | ||
d7350c3f | 2387 | /* |
d7350c3f FW |
2388 | * The current tracer is copied to avoid a global locking |
2389 | * all around. | |
2390 | */ | |
bc0c38d1 SR |
2391 | static void *s_start(struct seq_file *m, loff_t *pos) |
2392 | { | |
2393 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2394 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2395 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2396 | void *p = NULL; |
2397 | loff_t l = 0; | |
3928a8a2 | 2398 | int cpu; |
bc0c38d1 | 2399 | |
2fd196ec HT |
2400 | /* |
2401 | * copy the tracer to avoid using a global lock all around. | |
2402 | * iter->trace is a copy of current_trace, the pointer to the | |
2403 | * name may be used instead of a strcmp(), as iter->trace->name | |
2404 | * will point to the same string as current_trace->name. | |
2405 | */ | |
bc0c38d1 | 2406 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2407 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2408 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2409 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2410 | |
12883efb | 2411 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2412 | if (iter->snapshot && iter->trace->use_max_tr) |
2413 | return ERR_PTR(-EBUSY); | |
12883efb | 2414 | #endif |
debdd57f HT |
2415 | |
2416 | if (!iter->snapshot) | |
2417 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2418 | |
bc0c38d1 SR |
2419 | if (*pos != iter->pos) { |
2420 | iter->ent = NULL; | |
2421 | iter->cpu = 0; | |
2422 | iter->idx = -1; | |
2423 | ||
ae3b5093 | 2424 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2425 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2426 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2427 | } else |
2f26ebd5 | 2428 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2429 | |
ac91d854 | 2430 | iter->leftover = 0; |
bc0c38d1 SR |
2431 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2432 | ; | |
2433 | ||
2434 | } else { | |
a63ce5b3 SR |
2435 | /* |
2436 | * If we overflowed the seq_file before, then we want | |
2437 | * to just reuse the trace_seq buffer again. | |
2438 | */ | |
2439 | if (iter->leftover) | |
2440 | p = iter; | |
2441 | else { | |
2442 | l = *pos - 1; | |
2443 | p = s_next(m, p, &l); | |
2444 | } | |
bc0c38d1 SR |
2445 | } |
2446 | ||
4f535968 | 2447 | trace_event_read_lock(); |
7e53bd42 | 2448 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2449 | return p; |
2450 | } | |
2451 | ||
2452 | static void s_stop(struct seq_file *m, void *p) | |
2453 | { | |
7e53bd42 LJ |
2454 | struct trace_iterator *iter = m->private; |
2455 | ||
12883efb | 2456 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2457 | if (iter->snapshot && iter->trace->use_max_tr) |
2458 | return; | |
12883efb | 2459 | #endif |
debdd57f HT |
2460 | |
2461 | if (!iter->snapshot) | |
2462 | atomic_dec(&trace_record_cmdline_disabled); | |
12883efb | 2463 | |
7e53bd42 | 2464 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2465 | trace_event_read_unlock(); |
bc0c38d1 SR |
2466 | } |
2467 | ||
39eaf7ef | 2468 | static void |
12883efb SRRH |
2469 | get_total_entries(struct trace_buffer *buf, |
2470 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
2471 | { |
2472 | unsigned long count; | |
2473 | int cpu; | |
2474 | ||
2475 | *total = 0; | |
2476 | *entries = 0; | |
2477 | ||
2478 | for_each_tracing_cpu(cpu) { | |
12883efb | 2479 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2480 | /* |
2481 | * If this buffer has skipped entries, then we hold all | |
2482 | * entries for the trace and we need to ignore the | |
2483 | * ones before the time stamp. | |
2484 | */ | |
12883efb SRRH |
2485 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
2486 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2487 | /* total is the same as the entries */ |
2488 | *total += count; | |
2489 | } else | |
2490 | *total += count + | |
12883efb | 2491 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2492 | *entries += count; |
2493 | } | |
2494 | } | |
2495 | ||
e309b41d | 2496 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2497 | { |
a6168353 ME |
2498 | seq_puts(m, "# _------=> CPU# \n"); |
2499 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
2500 | seq_puts(m, "# | / _----=> need-resched \n"); | |
2501 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
2502 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
2503 | seq_puts(m, "# |||| / delay \n"); |
2504 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
2505 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2506 | } |
2507 | ||
12883efb | 2508 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 2509 | { |
39eaf7ef SR |
2510 | unsigned long total; |
2511 | unsigned long entries; | |
2512 | ||
12883efb | 2513 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
2514 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
2515 | entries, total, num_online_cpus()); | |
2516 | seq_puts(m, "#\n"); | |
2517 | } | |
2518 | ||
12883efb | 2519 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) |
39eaf7ef | 2520 | { |
12883efb | 2521 | print_event_info(buf, m); |
77271ce4 | 2522 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
a6168353 | 2523 | seq_puts(m, "# | | | | |\n"); |
bc0c38d1 SR |
2524 | } |
2525 | ||
12883efb | 2526 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) |
77271ce4 | 2527 | { |
12883efb | 2528 | print_event_info(buf, m); |
77271ce4 SR |
2529 | seq_puts(m, "# _-----=> irqs-off\n"); |
2530 | seq_puts(m, "# / _----=> need-resched\n"); | |
2531 | seq_puts(m, "# | / _---=> hardirq/softirq\n"); | |
2532 | seq_puts(m, "# || / _--=> preempt-depth\n"); | |
2533 | seq_puts(m, "# ||| / delay\n"); | |
2534 | seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); | |
2535 | seq_puts(m, "# | | | |||| | |\n"); | |
2536 | } | |
bc0c38d1 | 2537 | |
62b915f1 | 2538 | void |
bc0c38d1 SR |
2539 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2540 | { | |
2541 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
12883efb SRRH |
2542 | struct trace_buffer *buf = iter->trace_buffer; |
2543 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 2544 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2545 | unsigned long entries; |
2546 | unsigned long total; | |
bc0c38d1 SR |
2547 | const char *name = "preemption"; |
2548 | ||
d840f718 | 2549 | name = type->name; |
bc0c38d1 | 2550 | |
12883efb | 2551 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 2552 | |
888b55dc | 2553 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2554 | name, UTS_RELEASE); |
888b55dc | 2555 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2556 | "---------------------------------\n"); |
888b55dc | 2557 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2558 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2559 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2560 | entries, |
4c11d7ae | 2561 | total, |
12883efb | 2562 | buf->cpu, |
bc0c38d1 SR |
2563 | #if defined(CONFIG_PREEMPT_NONE) |
2564 | "server", | |
2565 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2566 | "desktop", | |
b5c21b45 | 2567 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2568 | "preempt", |
2569 | #else | |
2570 | "unknown", | |
2571 | #endif | |
2572 | /* These are reserved for later use */ | |
2573 | 0, 0, 0, 0); | |
2574 | #ifdef CONFIG_SMP | |
2575 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2576 | #else | |
2577 | seq_puts(m, ")\n"); | |
2578 | #endif | |
888b55dc KM |
2579 | seq_puts(m, "# -----------------\n"); |
2580 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2581 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2582 | data->comm, data->pid, |
2583 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2584 | data->policy, data->rt_priority); |
888b55dc | 2585 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2586 | |
2587 | if (data->critical_start) { | |
888b55dc | 2588 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2589 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2590 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2591 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2592 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2593 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2594 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2595 | } |
2596 | ||
888b55dc | 2597 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2598 | } |
2599 | ||
a309720c SR |
2600 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2601 | { | |
2602 | struct trace_seq *s = &iter->seq; | |
2603 | ||
12ef7d44 SR |
2604 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2605 | return; | |
2606 | ||
2607 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2608 | return; | |
2609 | ||
4462344e | 2610 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2611 | return; |
2612 | ||
12883efb | 2613 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
2614 | return; |
2615 | ||
4462344e | 2616 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2617 | |
2618 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2619 | if (iter->idx > 1) | |
2620 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2621 | iter->cpu); | |
a309720c SR |
2622 | } |
2623 | ||
2c4f035f | 2624 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2625 | { |
214023c3 | 2626 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2627 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2628 | struct trace_entry *entry; |
f633cef0 | 2629 | struct trace_event *event; |
bc0c38d1 | 2630 | |
4e3c3333 | 2631 | entry = iter->ent; |
dd0e545f | 2632 | |
a309720c SR |
2633 | test_cpu_buff_start(iter); |
2634 | ||
c4a8e8be | 2635 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2636 | |
c4a8e8be | 2637 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
2638 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2639 | if (!trace_print_lat_context(iter)) | |
2640 | goto partial; | |
2641 | } else { | |
2642 | if (!trace_print_context(iter)) | |
2643 | goto partial; | |
2644 | } | |
c4a8e8be | 2645 | } |
bc0c38d1 | 2646 | |
268ccda0 | 2647 | if (event) |
a9a57763 | 2648 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
2649 | |
2650 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
2651 | goto partial; | |
02b67518 | 2652 | |
2c4f035f | 2653 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2654 | partial: |
2655 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
2656 | } |
2657 | ||
2c4f035f | 2658 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2659 | { |
2660 | struct trace_seq *s = &iter->seq; | |
2661 | struct trace_entry *entry; | |
f633cef0 | 2662 | struct trace_event *event; |
f9896bf3 IM |
2663 | |
2664 | entry = iter->ent; | |
dd0e545f | 2665 | |
c4a8e8be | 2666 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
2667 | if (!trace_seq_printf(s, "%d %d %llu ", |
2668 | entry->pid, iter->cpu, iter->ts)) | |
2669 | goto partial; | |
c4a8e8be | 2670 | } |
f9896bf3 | 2671 | |
f633cef0 | 2672 | event = ftrace_find_event(entry->type); |
268ccda0 | 2673 | if (event) |
a9a57763 | 2674 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
2675 | |
2676 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
2677 | goto partial; | |
777e208d | 2678 | |
2c4f035f | 2679 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2680 | partial: |
2681 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
2682 | } |
2683 | ||
2c4f035f | 2684 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2685 | { |
2686 | struct trace_seq *s = &iter->seq; | |
2687 | unsigned char newline = '\n'; | |
2688 | struct trace_entry *entry; | |
f633cef0 | 2689 | struct trace_event *event; |
5e3ca0ec IM |
2690 | |
2691 | entry = iter->ent; | |
dd0e545f | 2692 | |
c4a8e8be FW |
2693 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2694 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
2695 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
2696 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
2697 | } | |
5e3ca0ec | 2698 | |
f633cef0 | 2699 | event = ftrace_find_event(entry->type); |
268ccda0 | 2700 | if (event) { |
a9a57763 | 2701 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2702 | if (ret != TRACE_TYPE_HANDLED) |
2703 | return ret; | |
2704 | } | |
7104f300 | 2705 | |
5e3ca0ec IM |
2706 | SEQ_PUT_FIELD_RET(s, newline); |
2707 | ||
2c4f035f | 2708 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
2709 | } |
2710 | ||
2c4f035f | 2711 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2712 | { |
2713 | struct trace_seq *s = &iter->seq; | |
2714 | struct trace_entry *entry; | |
f633cef0 | 2715 | struct trace_event *event; |
cb0f12aa IM |
2716 | |
2717 | entry = iter->ent; | |
dd0e545f | 2718 | |
c4a8e8be FW |
2719 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2720 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 2721 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2722 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2723 | } | |
cb0f12aa | 2724 | |
f633cef0 | 2725 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2726 | return event ? event->funcs->binary(iter, 0, event) : |
2727 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2728 | } |
2729 | ||
62b915f1 | 2730 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2731 | { |
6d158a81 | 2732 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2733 | int cpu; |
2734 | ||
9aba60fe | 2735 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 2736 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 2737 | cpu = iter->cpu_file; |
6d158a81 SR |
2738 | buf_iter = trace_buffer_iter(iter, cpu); |
2739 | if (buf_iter) { | |
2740 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2741 | return 0; |
2742 | } else { | |
12883efb | 2743 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
2744 | return 0; |
2745 | } | |
2746 | return 1; | |
2747 | } | |
2748 | ||
ab46428c | 2749 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2750 | buf_iter = trace_buffer_iter(iter, cpu); |
2751 | if (buf_iter) { | |
2752 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2753 | return 0; |
2754 | } else { | |
12883efb | 2755 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
2756 | return 0; |
2757 | } | |
bc0c38d1 | 2758 | } |
d769041f | 2759 | |
797d3712 | 2760 | return 1; |
bc0c38d1 SR |
2761 | } |
2762 | ||
4f535968 | 2763 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2764 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2765 | { |
2c4f035f FW |
2766 | enum print_line_t ret; |
2767 | ||
ee5e51f5 JO |
2768 | if (iter->lost_events && |
2769 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2770 | iter->cpu, iter->lost_events)) | |
2771 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2772 | |
2c4f035f FW |
2773 | if (iter->trace && iter->trace->print_line) { |
2774 | ret = iter->trace->print_line(iter); | |
2775 | if (ret != TRACE_TYPE_UNHANDLED) | |
2776 | return ret; | |
2777 | } | |
72829bc3 | 2778 | |
09ae7234 SRRH |
2779 | if (iter->ent->type == TRACE_BPUTS && |
2780 | trace_flags & TRACE_ITER_PRINTK && | |
2781 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
2782 | return trace_print_bputs_msg_only(iter); | |
2783 | ||
48ead020 FW |
2784 | if (iter->ent->type == TRACE_BPRINT && |
2785 | trace_flags & TRACE_ITER_PRINTK && | |
2786 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2787 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2788 | |
66896a85 FW |
2789 | if (iter->ent->type == TRACE_PRINT && |
2790 | trace_flags & TRACE_ITER_PRINTK && | |
2791 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2792 | return trace_print_printk_msg_only(iter); |
66896a85 | 2793 | |
cb0f12aa IM |
2794 | if (trace_flags & TRACE_ITER_BIN) |
2795 | return print_bin_fmt(iter); | |
2796 | ||
5e3ca0ec IM |
2797 | if (trace_flags & TRACE_ITER_HEX) |
2798 | return print_hex_fmt(iter); | |
2799 | ||
f9896bf3 IM |
2800 | if (trace_flags & TRACE_ITER_RAW) |
2801 | return print_raw_fmt(iter); | |
2802 | ||
f9896bf3 IM |
2803 | return print_trace_fmt(iter); |
2804 | } | |
2805 | ||
7e9a49ef JO |
2806 | void trace_latency_header(struct seq_file *m) |
2807 | { | |
2808 | struct trace_iterator *iter = m->private; | |
2809 | ||
2810 | /* print nothing if the buffers are empty */ | |
2811 | if (trace_empty(iter)) | |
2812 | return; | |
2813 | ||
2814 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2815 | print_trace_header(m, iter); | |
2816 | ||
2817 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2818 | print_lat_help_header(m); | |
2819 | } | |
2820 | ||
62b915f1 JO |
2821 | void trace_default_header(struct seq_file *m) |
2822 | { | |
2823 | struct trace_iterator *iter = m->private; | |
2824 | ||
f56e7f8e JO |
2825 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2826 | return; | |
2827 | ||
62b915f1 JO |
2828 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2829 | /* print nothing if the buffers are empty */ | |
2830 | if (trace_empty(iter)) | |
2831 | return; | |
2832 | print_trace_header(m, iter); | |
2833 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2834 | print_lat_help_header(m); | |
2835 | } else { | |
77271ce4 SR |
2836 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2837 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
12883efb | 2838 | print_func_help_header_irq(iter->trace_buffer, m); |
77271ce4 | 2839 | else |
12883efb | 2840 | print_func_help_header(iter->trace_buffer, m); |
77271ce4 | 2841 | } |
62b915f1 JO |
2842 | } |
2843 | } | |
2844 | ||
e0a413f6 SR |
2845 | static void test_ftrace_alive(struct seq_file *m) |
2846 | { | |
2847 | if (!ftrace_is_dead()) | |
2848 | return; | |
2849 | seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
2850 | seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n"); | |
2851 | } | |
2852 | ||
d8741e2e | 2853 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 2854 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 2855 | { |
d8741e2e SRRH |
2856 | seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n"); |
2857 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2858 | seq_printf(m, "# Takes a snapshot of the main buffer.\n"); | |
b9be6d02 | 2859 | seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n"); |
d8741e2e SRRH |
2860 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); |
2861 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2862 | } | |
f1affcaa SRRH |
2863 | |
2864 | static void show_snapshot_percpu_help(struct seq_file *m) | |
2865 | { | |
2866 | seq_printf(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); | |
2867 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP | |
2868 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2869 | seq_printf(m, "# Takes a snapshot of the main buffer for this cpu.\n"); | |
2870 | #else | |
2871 | seq_printf(m, "# echo 1 > snapshot : Not supported with this kernel.\n"); | |
2872 | seq_printf(m, "# Must use main snapshot file to allocate.\n"); | |
2873 | #endif | |
2874 | seq_printf(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n"); | |
2875 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); | |
2876 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2877 | } | |
2878 | ||
d8741e2e SRRH |
2879 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
2880 | { | |
45ad21ca | 2881 | if (iter->tr->allocated_snapshot) |
d8741e2e SRRH |
2882 | seq_printf(m, "#\n# * Snapshot is allocated *\n#\n"); |
2883 | else | |
2884 | seq_printf(m, "#\n# * Snapshot is freed *\n#\n"); | |
2885 | ||
2886 | seq_printf(m, "# Snapshot commands:\n"); | |
f1affcaa SRRH |
2887 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
2888 | show_snapshot_main_help(m); | |
2889 | else | |
2890 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
2891 | } |
2892 | #else | |
2893 | /* Should never be called */ | |
2894 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
2895 | #endif | |
2896 | ||
bc0c38d1 SR |
2897 | static int s_show(struct seq_file *m, void *v) |
2898 | { | |
2899 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2900 | int ret; |
bc0c38d1 SR |
2901 | |
2902 | if (iter->ent == NULL) { | |
2903 | if (iter->tr) { | |
2904 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2905 | seq_puts(m, "#\n"); | |
e0a413f6 | 2906 | test_ftrace_alive(m); |
bc0c38d1 | 2907 | } |
d8741e2e SRRH |
2908 | if (iter->snapshot && trace_empty(iter)) |
2909 | print_snapshot_help(m, iter); | |
2910 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 2911 | iter->trace->print_header(m); |
62b915f1 JO |
2912 | else |
2913 | trace_default_header(m); | |
2914 | ||
a63ce5b3 SR |
2915 | } else if (iter->leftover) { |
2916 | /* | |
2917 | * If we filled the seq_file buffer earlier, we | |
2918 | * want to just show it now. | |
2919 | */ | |
2920 | ret = trace_print_seq(m, &iter->seq); | |
2921 | ||
2922 | /* ret should this time be zero, but you never know */ | |
2923 | iter->leftover = ret; | |
2924 | ||
bc0c38d1 | 2925 | } else { |
f9896bf3 | 2926 | print_trace_line(iter); |
a63ce5b3 SR |
2927 | ret = trace_print_seq(m, &iter->seq); |
2928 | /* | |
2929 | * If we overflow the seq_file buffer, then it will | |
2930 | * ask us for this data again at start up. | |
2931 | * Use that instead. | |
2932 | * ret is 0 if seq_file write succeeded. | |
2933 | * -1 otherwise. | |
2934 | */ | |
2935 | iter->leftover = ret; | |
bc0c38d1 SR |
2936 | } |
2937 | ||
2938 | return 0; | |
2939 | } | |
2940 | ||
649e9c70 ON |
2941 | /* |
2942 | * Should be used after trace_array_get(), trace_types_lock | |
2943 | * ensures that i_cdev was already initialized. | |
2944 | */ | |
2945 | static inline int tracing_get_cpu(struct inode *inode) | |
2946 | { | |
2947 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
2948 | return (long)inode->i_cdev - 1; | |
2949 | return RING_BUFFER_ALL_CPUS; | |
2950 | } | |
2951 | ||
88e9d34c | 2952 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2953 | .start = s_start, |
2954 | .next = s_next, | |
2955 | .stop = s_stop, | |
2956 | .show = s_show, | |
bc0c38d1 SR |
2957 | }; |
2958 | ||
e309b41d | 2959 | static struct trace_iterator * |
6484c71c | 2960 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 2961 | { |
6484c71c | 2962 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 2963 | struct trace_iterator *iter; |
50e18b94 | 2964 | int cpu; |
bc0c38d1 | 2965 | |
85a2f9b4 SR |
2966 | if (tracing_disabled) |
2967 | return ERR_PTR(-ENODEV); | |
60a11774 | 2968 | |
50e18b94 | 2969 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2970 | if (!iter) |
2971 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2972 | |
6d158a81 SR |
2973 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
2974 | GFP_KERNEL); | |
93574fcc DC |
2975 | if (!iter->buffer_iter) |
2976 | goto release; | |
2977 | ||
d7350c3f FW |
2978 | /* |
2979 | * We make a copy of the current tracer to avoid concurrent | |
2980 | * changes on it while we are reading. | |
2981 | */ | |
bc0c38d1 | 2982 | mutex_lock(&trace_types_lock); |
d7350c3f | 2983 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2984 | if (!iter->trace) |
d7350c3f | 2985 | goto fail; |
85a2f9b4 | 2986 | |
2b6080f2 | 2987 | *iter->trace = *tr->current_trace; |
d7350c3f | 2988 | |
79f55997 | 2989 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2990 | goto fail; |
2991 | ||
12883efb SRRH |
2992 | iter->tr = tr; |
2993 | ||
2994 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
2995 | /* Currently only the top directory has a snapshot */ |
2996 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 2997 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 2998 | else |
12883efb SRRH |
2999 | #endif |
3000 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 3001 | iter->snapshot = snapshot; |
bc0c38d1 | 3002 | iter->pos = -1; |
6484c71c | 3003 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 3004 | mutex_init(&iter->mutex); |
bc0c38d1 | 3005 | |
8bba1bf5 MM |
3006 | /* Notify the tracer early; before we stop tracing. */ |
3007 | if (iter->trace && iter->trace->open) | |
a93751ca | 3008 | iter->trace->open(iter); |
8bba1bf5 | 3009 | |
12ef7d44 | 3010 | /* Annotate start of buffers if we had overruns */ |
12883efb | 3011 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
3012 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
3013 | ||
8be0709f | 3014 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 3015 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
3016 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
3017 | ||
debdd57f HT |
3018 | /* stop the trace while dumping if we are not opening "snapshot" */ |
3019 | if (!iter->snapshot) | |
2b6080f2 | 3020 | tracing_stop_tr(tr); |
2f26ebd5 | 3021 | |
ae3b5093 | 3022 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 3023 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 3024 | iter->buffer_iter[cpu] = |
12883efb | 3025 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3026 | } |
3027 | ring_buffer_read_prepare_sync(); | |
3028 | for_each_tracing_cpu(cpu) { | |
3029 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3030 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
3031 | } |
3032 | } else { | |
3033 | cpu = iter->cpu_file; | |
3928a8a2 | 3034 | iter->buffer_iter[cpu] = |
12883efb | 3035 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3036 | ring_buffer_read_prepare_sync(); |
3037 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3038 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
3039 | } |
3040 | ||
bc0c38d1 SR |
3041 | mutex_unlock(&trace_types_lock); |
3042 | ||
bc0c38d1 | 3043 | return iter; |
3928a8a2 | 3044 | |
d7350c3f | 3045 | fail: |
3928a8a2 | 3046 | mutex_unlock(&trace_types_lock); |
d7350c3f | 3047 | kfree(iter->trace); |
6d158a81 | 3048 | kfree(iter->buffer_iter); |
93574fcc | 3049 | release: |
50e18b94 JO |
3050 | seq_release_private(inode, file); |
3051 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
3052 | } |
3053 | ||
3054 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
3055 | { | |
60a11774 SR |
3056 | if (tracing_disabled) |
3057 | return -ENODEV; | |
3058 | ||
bc0c38d1 SR |
3059 | filp->private_data = inode->i_private; |
3060 | return 0; | |
3061 | } | |
3062 | ||
2e86421d GB |
3063 | bool tracing_is_disabled(void) |
3064 | { | |
3065 | return (tracing_disabled) ? true: false; | |
3066 | } | |
3067 | ||
7b85af63 SRRH |
3068 | /* |
3069 | * Open and update trace_array ref count. | |
3070 | * Must have the current trace_array passed to it. | |
3071 | */ | |
dcc30223 | 3072 | static int tracing_open_generic_tr(struct inode *inode, struct file *filp) |
7b85af63 SRRH |
3073 | { |
3074 | struct trace_array *tr = inode->i_private; | |
3075 | ||
3076 | if (tracing_disabled) | |
3077 | return -ENODEV; | |
3078 | ||
3079 | if (trace_array_get(tr) < 0) | |
3080 | return -ENODEV; | |
3081 | ||
3082 | filp->private_data = inode->i_private; | |
3083 | ||
3084 | return 0; | |
7b85af63 SRRH |
3085 | } |
3086 | ||
4fd27358 | 3087 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 3088 | { |
6484c71c | 3089 | struct trace_array *tr = inode->i_private; |
907f2784 | 3090 | struct seq_file *m = file->private_data; |
4acd4d00 | 3091 | struct trace_iterator *iter; |
3928a8a2 | 3092 | int cpu; |
bc0c38d1 | 3093 | |
ff451961 | 3094 | if (!(file->f_mode & FMODE_READ)) { |
6484c71c | 3095 | trace_array_put(tr); |
4acd4d00 | 3096 | return 0; |
ff451961 | 3097 | } |
4acd4d00 | 3098 | |
6484c71c | 3099 | /* Writes do not use seq_file */ |
4acd4d00 | 3100 | iter = m->private; |
bc0c38d1 | 3101 | mutex_lock(&trace_types_lock); |
a695cb58 | 3102 | |
3928a8a2 SR |
3103 | for_each_tracing_cpu(cpu) { |
3104 | if (iter->buffer_iter[cpu]) | |
3105 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
3106 | } | |
3107 | ||
bc0c38d1 SR |
3108 | if (iter->trace && iter->trace->close) |
3109 | iter->trace->close(iter); | |
3110 | ||
debdd57f HT |
3111 | if (!iter->snapshot) |
3112 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 3113 | tracing_start_tr(tr); |
f77d09a3 AL |
3114 | |
3115 | __trace_array_put(tr); | |
3116 | ||
bc0c38d1 SR |
3117 | mutex_unlock(&trace_types_lock); |
3118 | ||
d7350c3f | 3119 | mutex_destroy(&iter->mutex); |
b0dfa978 | 3120 | free_cpumask_var(iter->started); |
d7350c3f | 3121 | kfree(iter->trace); |
6d158a81 | 3122 | kfree(iter->buffer_iter); |
50e18b94 | 3123 | seq_release_private(inode, file); |
ff451961 | 3124 | |
bc0c38d1 SR |
3125 | return 0; |
3126 | } | |
3127 | ||
7b85af63 SRRH |
3128 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
3129 | { | |
3130 | struct trace_array *tr = inode->i_private; | |
3131 | ||
3132 | trace_array_put(tr); | |
bc0c38d1 SR |
3133 | return 0; |
3134 | } | |
3135 | ||
7b85af63 SRRH |
3136 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
3137 | { | |
3138 | struct trace_array *tr = inode->i_private; | |
3139 | ||
3140 | trace_array_put(tr); | |
3141 | ||
3142 | return single_release(inode, file); | |
3143 | } | |
3144 | ||
bc0c38d1 SR |
3145 | static int tracing_open(struct inode *inode, struct file *file) |
3146 | { | |
6484c71c | 3147 | struct trace_array *tr = inode->i_private; |
85a2f9b4 SR |
3148 | struct trace_iterator *iter; |
3149 | int ret = 0; | |
bc0c38d1 | 3150 | |
ff451961 SRRH |
3151 | if (trace_array_get(tr) < 0) |
3152 | return -ENODEV; | |
3153 | ||
4acd4d00 | 3154 | /* If this file was open for write, then erase contents */ |
6484c71c ON |
3155 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
3156 | int cpu = tracing_get_cpu(inode); | |
3157 | ||
3158 | if (cpu == RING_BUFFER_ALL_CPUS) | |
12883efb | 3159 | tracing_reset_online_cpus(&tr->trace_buffer); |
4acd4d00 | 3160 | else |
6484c71c | 3161 | tracing_reset(&tr->trace_buffer, cpu); |
4acd4d00 | 3162 | } |
bc0c38d1 | 3163 | |
4acd4d00 | 3164 | if (file->f_mode & FMODE_READ) { |
6484c71c | 3165 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
3166 | if (IS_ERR(iter)) |
3167 | ret = PTR_ERR(iter); | |
3168 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
3169 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3170 | } | |
ff451961 SRRH |
3171 | |
3172 | if (ret < 0) | |
3173 | trace_array_put(tr); | |
3174 | ||
bc0c38d1 SR |
3175 | return ret; |
3176 | } | |
3177 | ||
607e2ea1 SRRH |
3178 | /* |
3179 | * Some tracers are not suitable for instance buffers. | |
3180 | * A tracer is always available for the global array (toplevel) | |
3181 | * or if it explicitly states that it is. | |
3182 | */ | |
3183 | static bool | |
3184 | trace_ok_for_array(struct tracer *t, struct trace_array *tr) | |
3185 | { | |
3186 | return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; | |
3187 | } | |
3188 | ||
3189 | /* Find the next tracer that this trace array may use */ | |
3190 | static struct tracer * | |
3191 | get_tracer_for_array(struct trace_array *tr, struct tracer *t) | |
3192 | { | |
3193 | while (t && !trace_ok_for_array(t, tr)) | |
3194 | t = t->next; | |
3195 | ||
3196 | return t; | |
3197 | } | |
3198 | ||
e309b41d | 3199 | static void * |
bc0c38d1 SR |
3200 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3201 | { | |
607e2ea1 | 3202 | struct trace_array *tr = m->private; |
f129e965 | 3203 | struct tracer *t = v; |
bc0c38d1 SR |
3204 | |
3205 | (*pos)++; | |
3206 | ||
3207 | if (t) | |
607e2ea1 | 3208 | t = get_tracer_for_array(tr, t->next); |
bc0c38d1 | 3209 | |
bc0c38d1 SR |
3210 | return t; |
3211 | } | |
3212 | ||
3213 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3214 | { | |
607e2ea1 | 3215 | struct trace_array *tr = m->private; |
f129e965 | 3216 | struct tracer *t; |
bc0c38d1 SR |
3217 | loff_t l = 0; |
3218 | ||
3219 | mutex_lock(&trace_types_lock); | |
607e2ea1 SRRH |
3220 | |
3221 | t = get_tracer_for_array(tr, trace_types); | |
3222 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
3223 | ; | |
bc0c38d1 SR |
3224 | |
3225 | return t; | |
3226 | } | |
3227 | ||
3228 | static void t_stop(struct seq_file *m, void *p) | |
3229 | { | |
3230 | mutex_unlock(&trace_types_lock); | |
3231 | } | |
3232 | ||
3233 | static int t_show(struct seq_file *m, void *v) | |
3234 | { | |
3235 | struct tracer *t = v; | |
3236 | ||
3237 | if (!t) | |
3238 | return 0; | |
3239 | ||
3240 | seq_printf(m, "%s", t->name); | |
3241 | if (t->next) | |
3242 | seq_putc(m, ' '); | |
3243 | else | |
3244 | seq_putc(m, '\n'); | |
3245 | ||
3246 | return 0; | |
3247 | } | |
3248 | ||
88e9d34c | 3249 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
3250 | .start = t_start, |
3251 | .next = t_next, | |
3252 | .stop = t_stop, | |
3253 | .show = t_show, | |
bc0c38d1 SR |
3254 | }; |
3255 | ||
3256 | static int show_traces_open(struct inode *inode, struct file *file) | |
3257 | { | |
607e2ea1 SRRH |
3258 | struct trace_array *tr = inode->i_private; |
3259 | struct seq_file *m; | |
3260 | int ret; | |
3261 | ||
60a11774 SR |
3262 | if (tracing_disabled) |
3263 | return -ENODEV; | |
3264 | ||
607e2ea1 SRRH |
3265 | ret = seq_open(file, &show_traces_seq_ops); |
3266 | if (ret) | |
3267 | return ret; | |
3268 | ||
3269 | m = file->private_data; | |
3270 | m->private = tr; | |
3271 | ||
3272 | return 0; | |
bc0c38d1 SR |
3273 | } |
3274 | ||
4acd4d00 SR |
3275 | static ssize_t |
3276 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
3277 | size_t count, loff_t *ppos) | |
3278 | { | |
3279 | return count; | |
3280 | } | |
3281 | ||
098c879e | 3282 | loff_t tracing_lseek(struct file *file, loff_t offset, int whence) |
364829b1 | 3283 | { |
098c879e SRRH |
3284 | int ret; |
3285 | ||
364829b1 | 3286 | if (file->f_mode & FMODE_READ) |
098c879e | 3287 | ret = seq_lseek(file, offset, whence); |
364829b1 | 3288 | else |
098c879e SRRH |
3289 | file->f_pos = ret = 0; |
3290 | ||
3291 | return ret; | |
364829b1 SP |
3292 | } |
3293 | ||
5e2336a0 | 3294 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
3295 | .open = tracing_open, |
3296 | .read = seq_read, | |
4acd4d00 | 3297 | .write = tracing_write_stub, |
098c879e | 3298 | .llseek = tracing_lseek, |
4bf39a94 | 3299 | .release = tracing_release, |
bc0c38d1 SR |
3300 | }; |
3301 | ||
5e2336a0 | 3302 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
3303 | .open = show_traces_open, |
3304 | .read = seq_read, | |
3305 | .release = seq_release, | |
b444786f | 3306 | .llseek = seq_lseek, |
c7078de1 IM |
3307 | }; |
3308 | ||
36dfe925 IM |
3309 | /* |
3310 | * The tracer itself will not take this lock, but still we want | |
3311 | * to provide a consistent cpumask to user-space: | |
3312 | */ | |
3313 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
3314 | ||
3315 | /* | |
3316 | * Temporary storage for the character representation of the | |
3317 | * CPU bitmask (and one more byte for the newline): | |
3318 | */ | |
3319 | static char mask_str[NR_CPUS + 1]; | |
3320 | ||
c7078de1 IM |
3321 | static ssize_t |
3322 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
3323 | size_t count, loff_t *ppos) | |
3324 | { | |
ccfe9e42 | 3325 | struct trace_array *tr = file_inode(filp)->i_private; |
36dfe925 | 3326 | int len; |
c7078de1 IM |
3327 | |
3328 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 3329 | |
ccfe9e42 | 3330 | len = cpumask_scnprintf(mask_str, count, tr->tracing_cpumask); |
36dfe925 IM |
3331 | if (count - len < 2) { |
3332 | count = -EINVAL; | |
3333 | goto out_err; | |
3334 | } | |
3335 | len += sprintf(mask_str + len, "\n"); | |
3336 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
3337 | ||
3338 | out_err: | |
c7078de1 IM |
3339 | mutex_unlock(&tracing_cpumask_update_lock); |
3340 | ||
3341 | return count; | |
3342 | } | |
3343 | ||
3344 | static ssize_t | |
3345 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
3346 | size_t count, loff_t *ppos) | |
3347 | { | |
ccfe9e42 | 3348 | struct trace_array *tr = file_inode(filp)->i_private; |
9e01c1b7 | 3349 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 3350 | int err, cpu; |
9e01c1b7 RR |
3351 | |
3352 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
3353 | return -ENOMEM; | |
c7078de1 | 3354 | |
9e01c1b7 | 3355 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 3356 | if (err) |
36dfe925 IM |
3357 | goto err_unlock; |
3358 | ||
215368e8 LZ |
3359 | mutex_lock(&tracing_cpumask_update_lock); |
3360 | ||
a5e25883 | 3361 | local_irq_disable(); |
0b9b12c1 | 3362 | arch_spin_lock(&tr->max_lock); |
ab46428c | 3363 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
3364 | /* |
3365 | * Increase/decrease the disabled counter if we are | |
3366 | * about to flip a bit in the cpumask: | |
3367 | */ | |
ccfe9e42 | 3368 | if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3369 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3370 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3371 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 3372 | } |
ccfe9e42 | 3373 | if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3374 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3375 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3376 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
3377 | } |
3378 | } | |
0b9b12c1 | 3379 | arch_spin_unlock(&tr->max_lock); |
a5e25883 | 3380 | local_irq_enable(); |
36dfe925 | 3381 | |
ccfe9e42 | 3382 | cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
3383 | |
3384 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 3385 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
3386 | |
3387 | return count; | |
36dfe925 IM |
3388 | |
3389 | err_unlock: | |
215368e8 | 3390 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
3391 | |
3392 | return err; | |
c7078de1 IM |
3393 | } |
3394 | ||
5e2336a0 | 3395 | static const struct file_operations tracing_cpumask_fops = { |
ccfe9e42 | 3396 | .open = tracing_open_generic_tr, |
c7078de1 IM |
3397 | .read = tracing_cpumask_read, |
3398 | .write = tracing_cpumask_write, | |
ccfe9e42 | 3399 | .release = tracing_release_generic_tr, |
b444786f | 3400 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3401 | }; |
3402 | ||
fdb372ed | 3403 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 3404 | { |
d8e83d26 | 3405 | struct tracer_opt *trace_opts; |
2b6080f2 | 3406 | struct trace_array *tr = m->private; |
d8e83d26 | 3407 | u32 tracer_flags; |
d8e83d26 | 3408 | int i; |
adf9f195 | 3409 | |
d8e83d26 | 3410 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3411 | tracer_flags = tr->current_trace->flags->val; |
3412 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 3413 | |
bc0c38d1 SR |
3414 | for (i = 0; trace_options[i]; i++) { |
3415 | if (trace_flags & (1 << i)) | |
fdb372ed | 3416 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 3417 | else |
fdb372ed | 3418 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
3419 | } |
3420 | ||
adf9f195 FW |
3421 | for (i = 0; trace_opts[i].name; i++) { |
3422 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 3423 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 3424 | else |
fdb372ed | 3425 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 3426 | } |
d8e83d26 | 3427 | mutex_unlock(&trace_types_lock); |
adf9f195 | 3428 | |
fdb372ed | 3429 | return 0; |
bc0c38d1 | 3430 | } |
bc0c38d1 | 3431 | |
8c1a49ae | 3432 | static int __set_tracer_option(struct trace_array *tr, |
8d18eaaf LZ |
3433 | struct tracer_flags *tracer_flags, |
3434 | struct tracer_opt *opts, int neg) | |
3435 | { | |
8c1a49ae | 3436 | struct tracer *trace = tr->current_trace; |
8d18eaaf | 3437 | int ret; |
bc0c38d1 | 3438 | |
8c1a49ae | 3439 | ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); |
8d18eaaf LZ |
3440 | if (ret) |
3441 | return ret; | |
3442 | ||
3443 | if (neg) | |
3444 | tracer_flags->val &= ~opts->bit; | |
3445 | else | |
3446 | tracer_flags->val |= opts->bit; | |
3447 | return 0; | |
bc0c38d1 SR |
3448 | } |
3449 | ||
adf9f195 | 3450 | /* Try to assign a tracer specific option */ |
8c1a49ae | 3451 | static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) |
adf9f195 | 3452 | { |
8c1a49ae | 3453 | struct tracer *trace = tr->current_trace; |
7770841e | 3454 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 3455 | struct tracer_opt *opts = NULL; |
8d18eaaf | 3456 | int i; |
adf9f195 | 3457 | |
7770841e Z |
3458 | for (i = 0; tracer_flags->opts[i].name; i++) { |
3459 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 3460 | |
8d18eaaf | 3461 | if (strcmp(cmp, opts->name) == 0) |
8c1a49ae | 3462 | return __set_tracer_option(tr, trace->flags, opts, neg); |
adf9f195 | 3463 | } |
adf9f195 | 3464 | |
8d18eaaf | 3465 | return -EINVAL; |
adf9f195 FW |
3466 | } |
3467 | ||
613f04a0 SRRH |
3468 | /* Some tracers require overwrite to stay enabled */ |
3469 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
3470 | { | |
3471 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
3472 | return -1; | |
3473 | ||
3474 | return 0; | |
3475 | } | |
3476 | ||
2b6080f2 | 3477 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
3478 | { |
3479 | /* do nothing if flag is already set */ | |
3480 | if (!!(trace_flags & mask) == !!enabled) | |
613f04a0 SRRH |
3481 | return 0; |
3482 | ||
3483 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 | 3484 | if (tr->current_trace->flag_changed) |
bf6065b5 | 3485 | if (tr->current_trace->flag_changed(tr, mask, !!enabled)) |
613f04a0 | 3486 | return -EINVAL; |
af4617bd SR |
3487 | |
3488 | if (enabled) | |
3489 | trace_flags |= mask; | |
3490 | else | |
3491 | trace_flags &= ~mask; | |
e870e9a1 LZ |
3492 | |
3493 | if (mask == TRACE_ITER_RECORD_CMD) | |
3494 | trace_event_enable_cmd_record(enabled); | |
750912fa | 3495 | |
80902822 | 3496 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 3497 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 3498 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 3499 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
3500 | #endif |
3501 | } | |
81698831 SR |
3502 | |
3503 | if (mask == TRACE_ITER_PRINTK) | |
3504 | trace_printk_start_stop_comm(enabled); | |
613f04a0 SRRH |
3505 | |
3506 | return 0; | |
af4617bd SR |
3507 | } |
3508 | ||
2b6080f2 | 3509 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 3510 | { |
8d18eaaf | 3511 | char *cmp; |
bc0c38d1 | 3512 | int neg = 0; |
613f04a0 | 3513 | int ret = -ENODEV; |
bc0c38d1 SR |
3514 | int i; |
3515 | ||
7bcfaf54 | 3516 | cmp = strstrip(option); |
bc0c38d1 | 3517 | |
8d18eaaf | 3518 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3519 | neg = 1; |
3520 | cmp += 2; | |
3521 | } | |
3522 | ||
69d34da2 SRRH |
3523 | mutex_lock(&trace_types_lock); |
3524 | ||
bc0c38d1 | 3525 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3526 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3527 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3528 | break; |
3529 | } | |
3530 | } | |
adf9f195 FW |
3531 | |
3532 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3533 | if (!trace_options[i]) |
8c1a49ae | 3534 | ret = set_tracer_option(tr, cmp, neg); |
69d34da2 SRRH |
3535 | |
3536 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3537 | |
7bcfaf54 SR |
3538 | return ret; |
3539 | } | |
3540 | ||
3541 | static ssize_t | |
3542 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3543 | size_t cnt, loff_t *ppos) | |
3544 | { | |
2b6080f2 SR |
3545 | struct seq_file *m = filp->private_data; |
3546 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3547 | char buf[64]; |
613f04a0 | 3548 | int ret; |
7bcfaf54 SR |
3549 | |
3550 | if (cnt >= sizeof(buf)) | |
3551 | return -EINVAL; | |
3552 | ||
3553 | if (copy_from_user(&buf, ubuf, cnt)) | |
3554 | return -EFAULT; | |
3555 | ||
a8dd2176 SR |
3556 | buf[cnt] = 0; |
3557 | ||
2b6080f2 | 3558 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
3559 | if (ret < 0) |
3560 | return ret; | |
7bcfaf54 | 3561 | |
cf8517cf | 3562 | *ppos += cnt; |
bc0c38d1 SR |
3563 | |
3564 | return cnt; | |
3565 | } | |
3566 | ||
fdb372ed LZ |
3567 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
3568 | { | |
7b85af63 | 3569 | struct trace_array *tr = inode->i_private; |
f77d09a3 | 3570 | int ret; |
7b85af63 | 3571 | |
fdb372ed LZ |
3572 | if (tracing_disabled) |
3573 | return -ENODEV; | |
2b6080f2 | 3574 | |
7b85af63 SRRH |
3575 | if (trace_array_get(tr) < 0) |
3576 | return -ENODEV; | |
3577 | ||
f77d09a3 AL |
3578 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
3579 | if (ret < 0) | |
3580 | trace_array_put(tr); | |
3581 | ||
3582 | return ret; | |
fdb372ed LZ |
3583 | } |
3584 | ||
5e2336a0 | 3585 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
3586 | .open = tracing_trace_options_open, |
3587 | .read = seq_read, | |
3588 | .llseek = seq_lseek, | |
7b85af63 | 3589 | .release = tracing_single_release_tr, |
ee6bce52 | 3590 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
3591 | }; |
3592 | ||
7bd2f24c IM |
3593 | static const char readme_msg[] = |
3594 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
3595 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
3596 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
3597 | " Important files:\n" | |
3598 | " trace\t\t\t- The static contents of the buffer\n" | |
3599 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
3600 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
3601 | " current_tracer\t- function and latency tracers\n" | |
3602 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
3603 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" | |
3604 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
3605 | " trace_clock\t\t-change the clock used to order events\n" | |
3606 | " local: Per cpu clock but may not be synced across CPUs\n" | |
3607 | " global: Synced across CPUs but slows tracing down.\n" | |
3608 | " counter: Not a clock, but just an increment\n" | |
3609 | " uptime: Jiffy counter from time of boot\n" | |
3610 | " perf: Same clock that perf events use\n" | |
3611 | #ifdef CONFIG_X86_64 | |
3612 | " x86-tsc: TSC cycle counter\n" | |
3613 | #endif | |
3614 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" | |
3615 | " tracing_cpumask\t- Limit which CPUs to trace\n" | |
3616 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
3617 | "\t\t\t Remove sub-buffer with rmdir\n" | |
3618 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
71485c45 SRRH |
3619 | "\t\t\t Disable an option by adding a suffix 'no' to the\n" |
3620 | "\t\t\t option name\n" | |
939c7a4f | 3621 | " saved_cmdlines_size\t- echo command number in here to store comm-pid list\n" |
22f45649 SRRH |
3622 | #ifdef CONFIG_DYNAMIC_FTRACE |
3623 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
71485c45 SRRH |
3624 | " set_ftrace_filter\t- echo function name in here to only trace these\n" |
3625 | "\t\t\t functions\n" | |
3626 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3627 | "\t modules: Can select a group via module\n" | |
3628 | "\t Format: :mod:<module-name>\n" | |
3629 | "\t example: echo :mod:ext3 > set_ftrace_filter\n" | |
3630 | "\t triggers: a command to perform when function is hit\n" | |
3631 | "\t Format: <function>:<trigger>[:count]\n" | |
3632 | "\t trigger: traceon, traceoff\n" | |
3633 | "\t\t enable_event:<system>:<event>\n" | |
3634 | "\t\t disable_event:<system>:<event>\n" | |
22f45649 | 3635 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3636 | "\t\t stacktrace\n" |
22f45649 SRRH |
3637 | #endif |
3638 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3639 | "\t\t snapshot\n" |
22f45649 | 3640 | #endif |
17a280ea SRRH |
3641 | "\t\t dump\n" |
3642 | "\t\t cpudump\n" | |
71485c45 SRRH |
3643 | "\t example: echo do_fault:traceoff > set_ftrace_filter\n" |
3644 | "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
3645 | "\t The first one will disable tracing every time do_fault is hit\n" | |
3646 | "\t The second will disable tracing at most 3 times when do_trap is hit\n" | |
3647 | "\t The first time do trap is hit and it disables tracing, the\n" | |
3648 | "\t counter will decrement to 2. If tracing is already disabled,\n" | |
3649 | "\t the counter will not decrement. It only decrements when the\n" | |
3650 | "\t trigger did work\n" | |
3651 | "\t To remove trigger without count:\n" | |
3652 | "\t echo '!<function>:<trigger> > set_ftrace_filter\n" | |
3653 | "\t To remove trigger with a count:\n" | |
3654 | "\t echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
22f45649 | 3655 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" |
71485c45 SRRH |
3656 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" |
3657 | "\t modules: Can select a group via module command :mod:\n" | |
3658 | "\t Does not accept triggers\n" | |
22f45649 SRRH |
3659 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
3660 | #ifdef CONFIG_FUNCTION_TRACER | |
71485c45 SRRH |
3661 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" |
3662 | "\t\t (function)\n" | |
22f45649 SRRH |
3663 | #endif |
3664 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
3665 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
3666 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" | |
3667 | #endif | |
3668 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 SRRH |
3669 | "\n snapshot\t\t- Like 'trace' but shows the content of the static\n" |
3670 | "\t\t\t snapshot buffer. Read the contents for more\n" | |
3671 | "\t\t\t information\n" | |
22f45649 | 3672 | #endif |
991821c8 | 3673 | #ifdef CONFIG_STACK_TRACER |
22f45649 SRRH |
3674 | " stack_trace\t\t- Shows the max stack trace when active\n" |
3675 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
71485c45 SRRH |
3676 | "\t\t\t Write into this file to reset the max size (trigger a\n" |
3677 | "\t\t\t new trace)\n" | |
22f45649 | 3678 | #ifdef CONFIG_DYNAMIC_FTRACE |
71485c45 SRRH |
3679 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n" |
3680 | "\t\t\t traces\n" | |
22f45649 | 3681 | #endif |
991821c8 | 3682 | #endif /* CONFIG_STACK_TRACER */ |
26f25564 TZ |
3683 | " events/\t\t- Directory containing all trace event subsystems:\n" |
3684 | " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" | |
3685 | " events/<system>/\t- Directory containing all trace events for <system>:\n" | |
71485c45 SRRH |
3686 | " enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n" |
3687 | "\t\t\t events\n" | |
26f25564 | 3688 | " filter\t\t- If set, only events passing filter are traced\n" |
71485c45 SRRH |
3689 | " events/<system>/<event>/\t- Directory containing control files for\n" |
3690 | "\t\t\t <event>:\n" | |
26f25564 TZ |
3691 | " enable\t\t- Write 0/1 to enable/disable tracing of <event>\n" |
3692 | " filter\t\t- If set, only events passing filter are traced\n" | |
3693 | " trigger\t\t- If set, a command to perform when event is hit\n" | |
71485c45 SRRH |
3694 | "\t Format: <trigger>[:count][if <filter>]\n" |
3695 | "\t trigger: traceon, traceoff\n" | |
3696 | "\t enable_event:<system>:<event>\n" | |
3697 | "\t disable_event:<system>:<event>\n" | |
26f25564 | 3698 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3699 | "\t\t stacktrace\n" |
26f25564 TZ |
3700 | #endif |
3701 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3702 | "\t\t snapshot\n" |
26f25564 | 3703 | #endif |
71485c45 SRRH |
3704 | "\t example: echo traceoff > events/block/block_unplug/trigger\n" |
3705 | "\t echo traceoff:3 > events/block/block_unplug/trigger\n" | |
3706 | "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" | |
3707 | "\t events/block/block_unplug/trigger\n" | |
3708 | "\t The first disables tracing every time block_unplug is hit.\n" | |
3709 | "\t The second disables tracing the first 3 times block_unplug is hit.\n" | |
3710 | "\t The third enables the kmalloc event the first 3 times block_unplug\n" | |
3711 | "\t is hit and has value of greater than 1 for the 'nr_rq' event field.\n" | |
3712 | "\t Like function triggers, the counter is only decremented if it\n" | |
3713 | "\t enabled or disabled tracing.\n" | |
3714 | "\t To remove a trigger without a count:\n" | |
3715 | "\t echo '!<trigger> > <system>/<event>/trigger\n" | |
3716 | "\t To remove a trigger with a count:\n" | |
3717 | "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" | |
3718 | "\t Filters can be ignored when removing a trigger.\n" | |
7bd2f24c IM |
3719 | ; |
3720 | ||
3721 | static ssize_t | |
3722 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
3723 | size_t cnt, loff_t *ppos) | |
3724 | { | |
3725 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
3726 | readme_msg, strlen(readme_msg)); | |
3727 | } | |
3728 | ||
5e2336a0 | 3729 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
3730 | .open = tracing_open_generic, |
3731 | .read = tracing_readme_read, | |
b444786f | 3732 | .llseek = generic_file_llseek, |
7bd2f24c IM |
3733 | }; |
3734 | ||
42584c81 YY |
3735 | static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos) |
3736 | { | |
3737 | unsigned int *ptr = v; | |
69abe6a5 | 3738 | |
42584c81 YY |
3739 | if (*pos || m->count) |
3740 | ptr++; | |
69abe6a5 | 3741 | |
42584c81 | 3742 | (*pos)++; |
69abe6a5 | 3743 | |
939c7a4f YY |
3744 | for (; ptr < &savedcmd->map_cmdline_to_pid[savedcmd->cmdline_num]; |
3745 | ptr++) { | |
42584c81 YY |
3746 | if (*ptr == -1 || *ptr == NO_CMDLINE_MAP) |
3747 | continue; | |
69abe6a5 | 3748 | |
42584c81 YY |
3749 | return ptr; |
3750 | } | |
69abe6a5 | 3751 | |
42584c81 YY |
3752 | return NULL; |
3753 | } | |
3754 | ||
3755 | static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos) | |
3756 | { | |
3757 | void *v; | |
3758 | loff_t l = 0; | |
69abe6a5 | 3759 | |
4c27e756 SRRH |
3760 | preempt_disable(); |
3761 | arch_spin_lock(&trace_cmdline_lock); | |
3762 | ||
939c7a4f | 3763 | v = &savedcmd->map_cmdline_to_pid[0]; |
42584c81 YY |
3764 | while (l <= *pos) { |
3765 | v = saved_cmdlines_next(m, v, &l); | |
3766 | if (!v) | |
3767 | return NULL; | |
69abe6a5 AP |
3768 | } |
3769 | ||
42584c81 YY |
3770 | return v; |
3771 | } | |
3772 | ||
3773 | static void saved_cmdlines_stop(struct seq_file *m, void *v) | |
3774 | { | |
4c27e756 SRRH |
3775 | arch_spin_unlock(&trace_cmdline_lock); |
3776 | preempt_enable(); | |
42584c81 | 3777 | } |
69abe6a5 | 3778 | |
42584c81 YY |
3779 | static int saved_cmdlines_show(struct seq_file *m, void *v) |
3780 | { | |
3781 | char buf[TASK_COMM_LEN]; | |
3782 | unsigned int *pid = v; | |
69abe6a5 | 3783 | |
4c27e756 | 3784 | __trace_find_cmdline(*pid, buf); |
42584c81 YY |
3785 | seq_printf(m, "%d %s\n", *pid, buf); |
3786 | return 0; | |
3787 | } | |
3788 | ||
3789 | static const struct seq_operations tracing_saved_cmdlines_seq_ops = { | |
3790 | .start = saved_cmdlines_start, | |
3791 | .next = saved_cmdlines_next, | |
3792 | .stop = saved_cmdlines_stop, | |
3793 | .show = saved_cmdlines_show, | |
3794 | }; | |
3795 | ||
3796 | static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp) | |
3797 | { | |
3798 | if (tracing_disabled) | |
3799 | return -ENODEV; | |
3800 | ||
3801 | return seq_open(filp, &tracing_saved_cmdlines_seq_ops); | |
69abe6a5 AP |
3802 | } |
3803 | ||
3804 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
42584c81 YY |
3805 | .open = tracing_saved_cmdlines_open, |
3806 | .read = seq_read, | |
3807 | .llseek = seq_lseek, | |
3808 | .release = seq_release, | |
69abe6a5 AP |
3809 | }; |
3810 | ||
939c7a4f YY |
3811 | static ssize_t |
3812 | tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf, | |
3813 | size_t cnt, loff_t *ppos) | |
3814 | { | |
3815 | char buf[64]; | |
3816 | int r; | |
3817 | ||
3818 | arch_spin_lock(&trace_cmdline_lock); | |
a6af8fbf | 3819 | r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num); |
939c7a4f YY |
3820 | arch_spin_unlock(&trace_cmdline_lock); |
3821 | ||
3822 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3823 | } | |
3824 | ||
3825 | static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s) | |
3826 | { | |
3827 | kfree(s->saved_cmdlines); | |
3828 | kfree(s->map_cmdline_to_pid); | |
3829 | kfree(s); | |
3830 | } | |
3831 | ||
3832 | static int tracing_resize_saved_cmdlines(unsigned int val) | |
3833 | { | |
3834 | struct saved_cmdlines_buffer *s, *savedcmd_temp; | |
3835 | ||
a6af8fbf | 3836 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
939c7a4f YY |
3837 | if (!s) |
3838 | return -ENOMEM; | |
3839 | ||
3840 | if (allocate_cmdlines_buffer(val, s) < 0) { | |
3841 | kfree(s); | |
3842 | return -ENOMEM; | |
3843 | } | |
3844 | ||
3845 | arch_spin_lock(&trace_cmdline_lock); | |
3846 | savedcmd_temp = savedcmd; | |
3847 | savedcmd = s; | |
3848 | arch_spin_unlock(&trace_cmdline_lock); | |
3849 | free_saved_cmdlines_buffer(savedcmd_temp); | |
3850 | ||
3851 | return 0; | |
3852 | } | |
3853 | ||
3854 | static ssize_t | |
3855 | tracing_saved_cmdlines_size_write(struct file *filp, const char __user *ubuf, | |
3856 | size_t cnt, loff_t *ppos) | |
3857 | { | |
3858 | unsigned long val; | |
3859 | int ret; | |
3860 | ||
3861 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
3862 | if (ret) | |
3863 | return ret; | |
3864 | ||
3865 | /* must have at least 1 entry or less than PID_MAX_DEFAULT */ | |
3866 | if (!val || val > PID_MAX_DEFAULT) | |
3867 | return -EINVAL; | |
3868 | ||
3869 | ret = tracing_resize_saved_cmdlines((unsigned int)val); | |
3870 | if (ret < 0) | |
3871 | return ret; | |
3872 | ||
3873 | *ppos += cnt; | |
3874 | ||
3875 | return cnt; | |
3876 | } | |
3877 | ||
3878 | static const struct file_operations tracing_saved_cmdlines_size_fops = { | |
3879 | .open = tracing_open_generic, | |
3880 | .read = tracing_saved_cmdlines_size_read, | |
3881 | .write = tracing_saved_cmdlines_size_write, | |
3882 | }; | |
3883 | ||
bc0c38d1 SR |
3884 | static ssize_t |
3885 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
3886 | size_t cnt, loff_t *ppos) | |
3887 | { | |
2b6080f2 | 3888 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 3889 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
3890 | int r; |
3891 | ||
3892 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 3893 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
3894 | mutex_unlock(&trace_types_lock); |
3895 | ||
4bf39a94 | 3896 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3897 | } |
3898 | ||
b6f11df2 ACM |
3899 | int tracer_init(struct tracer *t, struct trace_array *tr) |
3900 | { | |
12883efb | 3901 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
3902 | return t->init(tr); |
3903 | } | |
3904 | ||
12883efb | 3905 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
3906 | { |
3907 | int cpu; | |
737223fb | 3908 | |
438ced17 | 3909 | for_each_tracing_cpu(cpu) |
12883efb | 3910 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
3911 | } |
3912 | ||
12883efb | 3913 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 3914 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
3915 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
3916 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
3917 | { |
3918 | int cpu, ret = 0; | |
3919 | ||
3920 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
3921 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
3922 | ret = ring_buffer_resize(trace_buf->buffer, |
3923 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
3924 | if (ret < 0) |
3925 | break; | |
12883efb SRRH |
3926 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
3927 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
3928 | } |
3929 | } else { | |
12883efb SRRH |
3930 | ret = ring_buffer_resize(trace_buf->buffer, |
3931 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 3932 | if (ret == 0) |
12883efb SRRH |
3933 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
3934 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
3935 | } |
3936 | ||
3937 | return ret; | |
3938 | } | |
12883efb | 3939 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 3940 | |
2b6080f2 SR |
3941 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
3942 | unsigned long size, int cpu) | |
73c5162a SR |
3943 | { |
3944 | int ret; | |
3945 | ||
3946 | /* | |
3947 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3948 | * we use the size that was given, and we can forget about |
3949 | * expanding it later. | |
73c5162a | 3950 | */ |
55034cd6 | 3951 | ring_buffer_expanded = true; |
73c5162a | 3952 | |
b382ede6 | 3953 | /* May be called before buffers are initialized */ |
12883efb | 3954 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
3955 | return 0; |
3956 | ||
12883efb | 3957 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
3958 | if (ret < 0) |
3959 | return ret; | |
3960 | ||
12883efb | 3961 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
3962 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
3963 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
3964 | goto out; |
3965 | ||
12883efb | 3966 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 3967 | if (ret < 0) { |
12883efb SRRH |
3968 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
3969 | &tr->trace_buffer, cpu); | |
73c5162a | 3970 | if (r < 0) { |
a123c52b SR |
3971 | /* |
3972 | * AARGH! We are left with different | |
3973 | * size max buffer!!!! | |
3974 | * The max buffer is our "snapshot" buffer. | |
3975 | * When a tracer needs a snapshot (one of the | |
3976 | * latency tracers), it swaps the max buffer | |
3977 | * with the saved snap shot. We succeeded to | |
3978 | * update the size of the main buffer, but failed to | |
3979 | * update the size of the max buffer. But when we tried | |
3980 | * to reset the main buffer to the original size, we | |
3981 | * failed there too. This is very unlikely to | |
3982 | * happen, but if it does, warn and kill all | |
3983 | * tracing. | |
3984 | */ | |
73c5162a SR |
3985 | WARN_ON(1); |
3986 | tracing_disabled = 1; | |
3987 | } | |
3988 | return ret; | |
3989 | } | |
3990 | ||
438ced17 | 3991 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3992 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 3993 | else |
12883efb | 3994 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 3995 | |
ef710e10 | 3996 | out: |
12883efb SRRH |
3997 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
3998 | ||
438ced17 | 3999 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 4000 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 4001 | else |
12883efb | 4002 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
4003 | |
4004 | return ret; | |
4005 | } | |
4006 | ||
2b6080f2 SR |
4007 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
4008 | unsigned long size, int cpu_id) | |
4f271a2a | 4009 | { |
83f40318 | 4010 | int ret = size; |
4f271a2a VN |
4011 | |
4012 | mutex_lock(&trace_types_lock); | |
4013 | ||
438ced17 VN |
4014 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
4015 | /* make sure, this cpu is enabled in the mask */ | |
4016 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
4017 | ret = -EINVAL; | |
4018 | goto out; | |
4019 | } | |
4020 | } | |
4f271a2a | 4021 | |
2b6080f2 | 4022 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
4023 | if (ret < 0) |
4024 | ret = -ENOMEM; | |
4025 | ||
438ced17 | 4026 | out: |
4f271a2a VN |
4027 | mutex_unlock(&trace_types_lock); |
4028 | ||
4029 | return ret; | |
4030 | } | |
4031 | ||
ef710e10 | 4032 | |
1852fcce SR |
4033 | /** |
4034 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
4035 | * | |
4036 | * To save on memory when the tracing is never used on a system with it | |
4037 | * configured in. The ring buffers are set to a minimum size. But once | |
4038 | * a user starts to use the tracing facility, then they need to grow | |
4039 | * to their default size. | |
4040 | * | |
4041 | * This function is to be called when a tracer is about to be used. | |
4042 | */ | |
4043 | int tracing_update_buffers(void) | |
4044 | { | |
4045 | int ret = 0; | |
4046 | ||
1027fcb2 | 4047 | mutex_lock(&trace_types_lock); |
1852fcce | 4048 | if (!ring_buffer_expanded) |
2b6080f2 | 4049 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 4050 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 4051 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
4052 | |
4053 | return ret; | |
4054 | } | |
4055 | ||
577b785f SR |
4056 | struct trace_option_dentry; |
4057 | ||
4058 | static struct trace_option_dentry * | |
2b6080f2 | 4059 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f SR |
4060 | |
4061 | static void | |
4062 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
4063 | ||
6b450d25 SRRH |
4064 | /* |
4065 | * Used to clear out the tracer before deletion of an instance. | |
4066 | * Must have trace_types_lock held. | |
4067 | */ | |
4068 | static void tracing_set_nop(struct trace_array *tr) | |
4069 | { | |
4070 | if (tr->current_trace == &nop_trace) | |
4071 | return; | |
4072 | ||
50512ab5 | 4073 | tr->current_trace->enabled--; |
6b450d25 SRRH |
4074 | |
4075 | if (tr->current_trace->reset) | |
4076 | tr->current_trace->reset(tr); | |
4077 | ||
4078 | tr->current_trace = &nop_trace; | |
4079 | } | |
4080 | ||
607e2ea1 | 4081 | static int tracing_set_tracer(struct trace_array *tr, const char *buf) |
bc0c38d1 | 4082 | { |
577b785f | 4083 | static struct trace_option_dentry *topts; |
bc0c38d1 | 4084 | struct tracer *t; |
12883efb | 4085 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 4086 | bool had_max_tr; |
12883efb | 4087 | #endif |
d9e54076 | 4088 | int ret = 0; |
bc0c38d1 | 4089 | |
1027fcb2 SR |
4090 | mutex_lock(&trace_types_lock); |
4091 | ||
73c5162a | 4092 | if (!ring_buffer_expanded) { |
2b6080f2 | 4093 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 4094 | RING_BUFFER_ALL_CPUS); |
73c5162a | 4095 | if (ret < 0) |
59f586db | 4096 | goto out; |
73c5162a SR |
4097 | ret = 0; |
4098 | } | |
4099 | ||
bc0c38d1 SR |
4100 | for (t = trace_types; t; t = t->next) { |
4101 | if (strcmp(t->name, buf) == 0) | |
4102 | break; | |
4103 | } | |
c2931e05 FW |
4104 | if (!t) { |
4105 | ret = -EINVAL; | |
4106 | goto out; | |
4107 | } | |
2b6080f2 | 4108 | if (t == tr->current_trace) |
bc0c38d1 SR |
4109 | goto out; |
4110 | ||
607e2ea1 SRRH |
4111 | /* Some tracers are only allowed for the top level buffer */ |
4112 | if (!trace_ok_for_array(t, tr)) { | |
4113 | ret = -EINVAL; | |
4114 | goto out; | |
4115 | } | |
4116 | ||
9f029e83 | 4117 | trace_branch_disable(); |
613f04a0 | 4118 | |
50512ab5 | 4119 | tr->current_trace->enabled--; |
613f04a0 | 4120 | |
2b6080f2 SR |
4121 | if (tr->current_trace->reset) |
4122 | tr->current_trace->reset(tr); | |
34600f0e | 4123 | |
12883efb | 4124 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 4125 | tr->current_trace = &nop_trace; |
34600f0e | 4126 | |
45ad21ca SRRH |
4127 | #ifdef CONFIG_TRACER_MAX_TRACE |
4128 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
4129 | |
4130 | if (had_max_tr && !t->use_max_tr) { | |
4131 | /* | |
4132 | * We need to make sure that the update_max_tr sees that | |
4133 | * current_trace changed to nop_trace to keep it from | |
4134 | * swapping the buffers after we resize it. | |
4135 | * The update_max_tr is called from interrupts disabled | |
4136 | * so a synchronized_sched() is sufficient. | |
4137 | */ | |
4138 | synchronize_sched(); | |
3209cff4 | 4139 | free_snapshot(tr); |
ef710e10 | 4140 | } |
12883efb | 4141 | #endif |
f1b21c9a SRRH |
4142 | /* Currently, only the top instance has options */ |
4143 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { | |
4144 | destroy_trace_option_files(topts); | |
4145 | topts = create_trace_option_files(tr, t); | |
4146 | } | |
12883efb SRRH |
4147 | |
4148 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 4149 | if (t->use_max_tr && !had_max_tr) { |
3209cff4 | 4150 | ret = alloc_snapshot(tr); |
d60da506 HT |
4151 | if (ret < 0) |
4152 | goto out; | |
ef710e10 | 4153 | } |
12883efb | 4154 | #endif |
577b785f | 4155 | |
1c80025a | 4156 | if (t->init) { |
b6f11df2 | 4157 | ret = tracer_init(t, tr); |
1c80025a FW |
4158 | if (ret) |
4159 | goto out; | |
4160 | } | |
bc0c38d1 | 4161 | |
2b6080f2 | 4162 | tr->current_trace = t; |
50512ab5 | 4163 | tr->current_trace->enabled++; |
9f029e83 | 4164 | trace_branch_enable(tr); |
bc0c38d1 SR |
4165 | out: |
4166 | mutex_unlock(&trace_types_lock); | |
4167 | ||
d9e54076 PZ |
4168 | return ret; |
4169 | } | |
4170 | ||
4171 | static ssize_t | |
4172 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
4173 | size_t cnt, loff_t *ppos) | |
4174 | { | |
607e2ea1 | 4175 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 4176 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
4177 | int i; |
4178 | size_t ret; | |
e6e7a65a FW |
4179 | int err; |
4180 | ||
4181 | ret = cnt; | |
d9e54076 | 4182 | |
ee6c2c1b LZ |
4183 | if (cnt > MAX_TRACER_SIZE) |
4184 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
4185 | |
4186 | if (copy_from_user(&buf, ubuf, cnt)) | |
4187 | return -EFAULT; | |
4188 | ||
4189 | buf[cnt] = 0; | |
4190 | ||
4191 | /* strip ending whitespace. */ | |
4192 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
4193 | buf[i] = 0; | |
4194 | ||
607e2ea1 | 4195 | err = tracing_set_tracer(tr, buf); |
e6e7a65a FW |
4196 | if (err) |
4197 | return err; | |
d9e54076 | 4198 | |
cf8517cf | 4199 | *ppos += ret; |
bc0c38d1 | 4200 | |
c2931e05 | 4201 | return ret; |
bc0c38d1 SR |
4202 | } |
4203 | ||
4204 | static ssize_t | |
4205 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
4206 | size_t cnt, loff_t *ppos) | |
4207 | { | |
4208 | unsigned long *ptr = filp->private_data; | |
4209 | char buf[64]; | |
4210 | int r; | |
4211 | ||
cffae437 | 4212 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 4213 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
4214 | if (r > sizeof(buf)) |
4215 | r = sizeof(buf); | |
4bf39a94 | 4216 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
4217 | } |
4218 | ||
4219 | static ssize_t | |
4220 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
4221 | size_t cnt, loff_t *ppos) | |
4222 | { | |
5e39841c | 4223 | unsigned long *ptr = filp->private_data; |
5e39841c | 4224 | unsigned long val; |
c6caeeb1 | 4225 | int ret; |
bc0c38d1 | 4226 | |
22fe9b54 PH |
4227 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4228 | if (ret) | |
c6caeeb1 | 4229 | return ret; |
bc0c38d1 SR |
4230 | |
4231 | *ptr = val * 1000; | |
4232 | ||
4233 | return cnt; | |
4234 | } | |
4235 | ||
b3806b43 SR |
4236 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
4237 | { | |
15544209 | 4238 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4239 | struct trace_iterator *iter; |
b04cc6b1 | 4240 | int ret = 0; |
b3806b43 SR |
4241 | |
4242 | if (tracing_disabled) | |
4243 | return -ENODEV; | |
4244 | ||
7b85af63 SRRH |
4245 | if (trace_array_get(tr) < 0) |
4246 | return -ENODEV; | |
4247 | ||
b04cc6b1 FW |
4248 | mutex_lock(&trace_types_lock); |
4249 | ||
b3806b43 SR |
4250 | /* create a buffer to store the information to pass to userspace */ |
4251 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
4252 | if (!iter) { |
4253 | ret = -ENOMEM; | |
f77d09a3 | 4254 | __trace_array_put(tr); |
b04cc6b1 FW |
4255 | goto out; |
4256 | } | |
b3806b43 | 4257 | |
d7350c3f FW |
4258 | /* |
4259 | * We make a copy of the current tracer to avoid concurrent | |
4260 | * changes on it while we are reading. | |
4261 | */ | |
4262 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
4263 | if (!iter->trace) { | |
4264 | ret = -ENOMEM; | |
4265 | goto fail; | |
4266 | } | |
2b6080f2 | 4267 | *iter->trace = *tr->current_trace; |
d7350c3f | 4268 | |
4462344e | 4269 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 4270 | ret = -ENOMEM; |
d7350c3f | 4271 | goto fail; |
4462344e RR |
4272 | } |
4273 | ||
a309720c | 4274 | /* trace pipe does not show start of buffer */ |
4462344e | 4275 | cpumask_setall(iter->started); |
a309720c | 4276 | |
112f38a7 SR |
4277 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
4278 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
4279 | ||
8be0709f | 4280 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 4281 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
4282 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
4283 | ||
15544209 ON |
4284 | iter->tr = tr; |
4285 | iter->trace_buffer = &tr->trace_buffer; | |
4286 | iter->cpu_file = tracing_get_cpu(inode); | |
d7350c3f | 4287 | mutex_init(&iter->mutex); |
b3806b43 SR |
4288 | filp->private_data = iter; |
4289 | ||
107bad8b SR |
4290 | if (iter->trace->pipe_open) |
4291 | iter->trace->pipe_open(iter); | |
107bad8b | 4292 | |
b444786f | 4293 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
4294 | out: |
4295 | mutex_unlock(&trace_types_lock); | |
4296 | return ret; | |
d7350c3f FW |
4297 | |
4298 | fail: | |
4299 | kfree(iter->trace); | |
4300 | kfree(iter); | |
7b85af63 | 4301 | __trace_array_put(tr); |
d7350c3f FW |
4302 | mutex_unlock(&trace_types_lock); |
4303 | return ret; | |
b3806b43 SR |
4304 | } |
4305 | ||
4306 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
4307 | { | |
4308 | struct trace_iterator *iter = file->private_data; | |
15544209 | 4309 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4310 | |
b04cc6b1 FW |
4311 | mutex_lock(&trace_types_lock); |
4312 | ||
29bf4a5e | 4313 | if (iter->trace->pipe_close) |
c521efd1 SR |
4314 | iter->trace->pipe_close(iter); |
4315 | ||
b04cc6b1 FW |
4316 | mutex_unlock(&trace_types_lock); |
4317 | ||
4462344e | 4318 | free_cpumask_var(iter->started); |
d7350c3f FW |
4319 | mutex_destroy(&iter->mutex); |
4320 | kfree(iter->trace); | |
b3806b43 | 4321 | kfree(iter); |
b3806b43 | 4322 | |
7b85af63 SRRH |
4323 | trace_array_put(tr); |
4324 | ||
b3806b43 SR |
4325 | return 0; |
4326 | } | |
4327 | ||
2a2cc8f7 | 4328 | static unsigned int |
cc60cdc9 | 4329 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 4330 | { |
15693458 SRRH |
4331 | /* Iterators are static, they should be filled or empty */ |
4332 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
4333 | return POLLIN | POLLRDNORM; | |
2a2cc8f7 | 4334 | |
15693458 | 4335 | if (trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
4336 | /* |
4337 | * Always select as readable when in blocking mode | |
4338 | */ | |
4339 | return POLLIN | POLLRDNORM; | |
15693458 | 4340 | else |
12883efb | 4341 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 4342 | filp, poll_table); |
2a2cc8f7 | 4343 | } |
2a2cc8f7 | 4344 | |
cc60cdc9 SR |
4345 | static unsigned int |
4346 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
4347 | { | |
4348 | struct trace_iterator *iter = filp->private_data; | |
4349 | ||
4350 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
4351 | } |
4352 | ||
ff98781b EGM |
4353 | /* Must be called with trace_types_lock mutex held. */ |
4354 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
4355 | { |
4356 | struct trace_iterator *iter = filp->private_data; | |
8b8b3683 | 4357 | int ret; |
b3806b43 | 4358 | |
b3806b43 | 4359 | while (trace_empty(iter)) { |
2dc8f095 | 4360 | |
107bad8b | 4361 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 4362 | return -EAGAIN; |
107bad8b | 4363 | } |
2dc8f095 | 4364 | |
b3806b43 | 4365 | /* |
250bfd3d | 4366 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
4367 | * We still block if tracing is disabled, but we have never |
4368 | * read anything. This allows a user to cat this file, and | |
4369 | * then enable tracing. But after we have read something, | |
4370 | * we give an EOF when tracing is again disabled. | |
4371 | * | |
4372 | * iter->pos will be 0 if we haven't read anything. | |
4373 | */ | |
10246fa3 | 4374 | if (!tracing_is_on() && iter->pos) |
b3806b43 | 4375 | break; |
f4874261 SRRH |
4376 | |
4377 | mutex_unlock(&iter->mutex); | |
4378 | ||
8b8b3683 | 4379 | ret = wait_on_pipe(iter); |
f4874261 SRRH |
4380 | |
4381 | mutex_lock(&iter->mutex); | |
4382 | ||
8b8b3683 SRRH |
4383 | if (ret) |
4384 | return ret; | |
4385 | ||
f4874261 SRRH |
4386 | if (signal_pending(current)) |
4387 | return -EINTR; | |
b3806b43 SR |
4388 | } |
4389 | ||
ff98781b EGM |
4390 | return 1; |
4391 | } | |
4392 | ||
4393 | /* | |
4394 | * Consumer reader. | |
4395 | */ | |
4396 | static ssize_t | |
4397 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
4398 | size_t cnt, loff_t *ppos) | |
4399 | { | |
4400 | struct trace_iterator *iter = filp->private_data; | |
2b6080f2 | 4401 | struct trace_array *tr = iter->tr; |
ff98781b EGM |
4402 | ssize_t sret; |
4403 | ||
4404 | /* return any leftover data */ | |
4405 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
4406 | if (sret != -EBUSY) | |
4407 | return sret; | |
4408 | ||
f9520750 | 4409 | trace_seq_init(&iter->seq); |
ff98781b | 4410 | |
d7350c3f | 4411 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 4412 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4413 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4414 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4415 | mutex_unlock(&trace_types_lock); |
4416 | ||
4417 | /* | |
4418 | * Avoid more than one consumer on a single file descriptor | |
4419 | * This is just a matter of traces coherency, the ring buffer itself | |
4420 | * is protected. | |
4421 | */ | |
4422 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
4423 | if (iter->trace->read) { |
4424 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
4425 | if (sret) | |
4426 | goto out; | |
4427 | } | |
4428 | ||
4429 | waitagain: | |
4430 | sret = tracing_wait_pipe(filp); | |
4431 | if (sret <= 0) | |
4432 | goto out; | |
4433 | ||
b3806b43 | 4434 | /* stop when tracing is finished */ |
ff98781b EGM |
4435 | if (trace_empty(iter)) { |
4436 | sret = 0; | |
107bad8b | 4437 | goto out; |
ff98781b | 4438 | } |
b3806b43 SR |
4439 | |
4440 | if (cnt >= PAGE_SIZE) | |
4441 | cnt = PAGE_SIZE - 1; | |
4442 | ||
53d0aa77 | 4443 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
4444 | memset(&iter->seq, 0, |
4445 | sizeof(struct trace_iterator) - | |
4446 | offsetof(struct trace_iterator, seq)); | |
ed5467da | 4447 | cpumask_clear(iter->started); |
4823ed7e | 4448 | iter->pos = -1; |
b3806b43 | 4449 | |
4f535968 | 4450 | trace_event_read_lock(); |
7e53bd42 | 4451 | trace_access_lock(iter->cpu_file); |
955b61e5 | 4452 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 4453 | enum print_line_t ret; |
088b1e42 SR |
4454 | int len = iter->seq.len; |
4455 | ||
f9896bf3 | 4456 | ret = print_trace_line(iter); |
2c4f035f | 4457 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
4458 | /* don't print partial lines */ |
4459 | iter->seq.len = len; | |
b3806b43 | 4460 | break; |
088b1e42 | 4461 | } |
b91facc3 FW |
4462 | if (ret != TRACE_TYPE_NO_CONSUME) |
4463 | trace_consume(iter); | |
b3806b43 SR |
4464 | |
4465 | if (iter->seq.len >= cnt) | |
4466 | break; | |
ee5e51f5 JO |
4467 | |
4468 | /* | |
4469 | * Setting the full flag means we reached the trace_seq buffer | |
4470 | * size and we should leave by partial output condition above. | |
4471 | * One of the trace_seq_* functions is not used properly. | |
4472 | */ | |
4473 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
4474 | iter->ent->type); | |
b3806b43 | 4475 | } |
7e53bd42 | 4476 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4477 | trace_event_read_unlock(); |
b3806b43 | 4478 | |
b3806b43 | 4479 | /* Now copy what we have to the user */ |
6c6c2796 PP |
4480 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
4481 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 4482 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
4483 | |
4484 | /* | |
25985edc | 4485 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
4486 | * entries, go back to wait for more entries. |
4487 | */ | |
6c6c2796 | 4488 | if (sret == -EBUSY) |
9ff4b974 | 4489 | goto waitagain; |
b3806b43 | 4490 | |
107bad8b | 4491 | out: |
d7350c3f | 4492 | mutex_unlock(&iter->mutex); |
107bad8b | 4493 | |
6c6c2796 | 4494 | return sret; |
b3806b43 SR |
4495 | } |
4496 | ||
3c56819b EGM |
4497 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, |
4498 | unsigned int idx) | |
4499 | { | |
4500 | __free_page(spd->pages[idx]); | |
4501 | } | |
4502 | ||
28dfef8f | 4503 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 | 4504 | .can_merge = 0, |
34cd4998 | 4505 | .confirm = generic_pipe_buf_confirm, |
92fdd98c | 4506 | .release = generic_pipe_buf_release, |
34cd4998 SR |
4507 | .steal = generic_pipe_buf_steal, |
4508 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
4509 | }; |
4510 | ||
34cd4998 | 4511 | static size_t |
fa7c7f6e | 4512 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
4513 | { |
4514 | size_t count; | |
4515 | int ret; | |
4516 | ||
4517 | /* Seq buffer is page-sized, exactly what we need. */ | |
4518 | for (;;) { | |
4519 | count = iter->seq.len; | |
4520 | ret = print_trace_line(iter); | |
4521 | count = iter->seq.len - count; | |
4522 | if (rem < count) { | |
4523 | rem = 0; | |
4524 | iter->seq.len -= count; | |
4525 | break; | |
4526 | } | |
4527 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
4528 | iter->seq.len -= count; | |
4529 | break; | |
4530 | } | |
4531 | ||
74e7ff8c LJ |
4532 | if (ret != TRACE_TYPE_NO_CONSUME) |
4533 | trace_consume(iter); | |
34cd4998 | 4534 | rem -= count; |
955b61e5 | 4535 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
4536 | rem = 0; |
4537 | iter->ent = NULL; | |
4538 | break; | |
4539 | } | |
4540 | } | |
4541 | ||
4542 | return rem; | |
4543 | } | |
4544 | ||
3c56819b EGM |
4545 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
4546 | loff_t *ppos, | |
4547 | struct pipe_inode_info *pipe, | |
4548 | size_t len, | |
4549 | unsigned int flags) | |
4550 | { | |
35f3d14d JA |
4551 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
4552 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
4553 | struct trace_iterator *iter = filp->private_data; |
4554 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
4555 | .pages = pages_def, |
4556 | .partial = partial_def, | |
34cd4998 | 4557 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 4558 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
4559 | .flags = flags, |
4560 | .ops = &tracing_pipe_buf_ops, | |
4561 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 4562 | }; |
2b6080f2 | 4563 | struct trace_array *tr = iter->tr; |
3c56819b | 4564 | ssize_t ret; |
34cd4998 | 4565 | size_t rem; |
3c56819b EGM |
4566 | unsigned int i; |
4567 | ||
35f3d14d JA |
4568 | if (splice_grow_spd(pipe, &spd)) |
4569 | return -ENOMEM; | |
4570 | ||
d7350c3f | 4571 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 4572 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4573 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4574 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4575 | mutex_unlock(&trace_types_lock); |
4576 | ||
4577 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
4578 | |
4579 | if (iter->trace->splice_read) { | |
4580 | ret = iter->trace->splice_read(iter, filp, | |
4581 | ppos, pipe, len, flags); | |
4582 | if (ret) | |
34cd4998 | 4583 | goto out_err; |
3c56819b EGM |
4584 | } |
4585 | ||
4586 | ret = tracing_wait_pipe(filp); | |
4587 | if (ret <= 0) | |
34cd4998 | 4588 | goto out_err; |
3c56819b | 4589 | |
955b61e5 | 4590 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 4591 | ret = -EFAULT; |
34cd4998 | 4592 | goto out_err; |
3c56819b EGM |
4593 | } |
4594 | ||
4f535968 | 4595 | trace_event_read_lock(); |
7e53bd42 | 4596 | trace_access_lock(iter->cpu_file); |
4f535968 | 4597 | |
3c56819b | 4598 | /* Fill as many pages as possible. */ |
a786c06d | 4599 | for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) { |
35f3d14d JA |
4600 | spd.pages[i] = alloc_page(GFP_KERNEL); |
4601 | if (!spd.pages[i]) | |
34cd4998 | 4602 | break; |
3c56819b | 4603 | |
fa7c7f6e | 4604 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
4605 | |
4606 | /* Copy the data into the page, so we can start over. */ | |
4607 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 4608 | page_address(spd.pages[i]), |
3c56819b EGM |
4609 | iter->seq.len); |
4610 | if (ret < 0) { | |
35f3d14d | 4611 | __free_page(spd.pages[i]); |
3c56819b EGM |
4612 | break; |
4613 | } | |
35f3d14d JA |
4614 | spd.partial[i].offset = 0; |
4615 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 4616 | |
f9520750 | 4617 | trace_seq_init(&iter->seq); |
3c56819b EGM |
4618 | } |
4619 | ||
7e53bd42 | 4620 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4621 | trace_event_read_unlock(); |
d7350c3f | 4622 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
4623 | |
4624 | spd.nr_pages = i; | |
4625 | ||
35f3d14d JA |
4626 | ret = splice_to_pipe(pipe, &spd); |
4627 | out: | |
047fe360 | 4628 | splice_shrink_spd(&spd); |
35f3d14d | 4629 | return ret; |
3c56819b | 4630 | |
34cd4998 | 4631 | out_err: |
d7350c3f | 4632 | mutex_unlock(&iter->mutex); |
35f3d14d | 4633 | goto out; |
3c56819b EGM |
4634 | } |
4635 | ||
a98a3c3f SR |
4636 | static ssize_t |
4637 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
4638 | size_t cnt, loff_t *ppos) | |
4639 | { | |
0bc392ee ON |
4640 | struct inode *inode = file_inode(filp); |
4641 | struct trace_array *tr = inode->i_private; | |
4642 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
4643 | char buf[64]; |
4644 | int r = 0; | |
4645 | ssize_t ret; | |
a98a3c3f | 4646 | |
db526ca3 | 4647 | mutex_lock(&trace_types_lock); |
438ced17 | 4648 | |
0bc392ee | 4649 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
4650 | int cpu, buf_size_same; |
4651 | unsigned long size; | |
4652 | ||
4653 | size = 0; | |
4654 | buf_size_same = 1; | |
4655 | /* check if all cpu sizes are same */ | |
4656 | for_each_tracing_cpu(cpu) { | |
4657 | /* fill in the size from first enabled cpu */ | |
4658 | if (size == 0) | |
12883efb SRRH |
4659 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
4660 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
4661 | buf_size_same = 0; |
4662 | break; | |
4663 | } | |
4664 | } | |
4665 | ||
4666 | if (buf_size_same) { | |
4667 | if (!ring_buffer_expanded) | |
4668 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
4669 | size >> 10, | |
4670 | trace_buf_size >> 10); | |
4671 | else | |
4672 | r = sprintf(buf, "%lu\n", size >> 10); | |
4673 | } else | |
4674 | r = sprintf(buf, "X\n"); | |
4675 | } else | |
0bc392ee | 4676 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10); |
438ced17 | 4677 | |
db526ca3 SR |
4678 | mutex_unlock(&trace_types_lock); |
4679 | ||
438ced17 VN |
4680 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
4681 | return ret; | |
a98a3c3f SR |
4682 | } |
4683 | ||
4684 | static ssize_t | |
4685 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
4686 | size_t cnt, loff_t *ppos) | |
4687 | { | |
0bc392ee ON |
4688 | struct inode *inode = file_inode(filp); |
4689 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 4690 | unsigned long val; |
4f271a2a | 4691 | int ret; |
a98a3c3f | 4692 | |
22fe9b54 PH |
4693 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4694 | if (ret) | |
c6caeeb1 | 4695 | return ret; |
a98a3c3f SR |
4696 | |
4697 | /* must have at least 1 entry */ | |
4698 | if (!val) | |
4699 | return -EINVAL; | |
4700 | ||
1696b2b0 SR |
4701 | /* value is in KB */ |
4702 | val <<= 10; | |
0bc392ee | 4703 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
4704 | if (ret < 0) |
4705 | return ret; | |
a98a3c3f | 4706 | |
cf8517cf | 4707 | *ppos += cnt; |
a98a3c3f | 4708 | |
4f271a2a VN |
4709 | return cnt; |
4710 | } | |
bf5e6519 | 4711 | |
f81ab074 VN |
4712 | static ssize_t |
4713 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
4714 | size_t cnt, loff_t *ppos) | |
4715 | { | |
4716 | struct trace_array *tr = filp->private_data; | |
4717 | char buf[64]; | |
4718 | int r, cpu; | |
4719 | unsigned long size = 0, expanded_size = 0; | |
4720 | ||
4721 | mutex_lock(&trace_types_lock); | |
4722 | for_each_tracing_cpu(cpu) { | |
12883efb | 4723 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
4724 | if (!ring_buffer_expanded) |
4725 | expanded_size += trace_buf_size >> 10; | |
4726 | } | |
4727 | if (ring_buffer_expanded) | |
4728 | r = sprintf(buf, "%lu\n", size); | |
4729 | else | |
4730 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
4731 | mutex_unlock(&trace_types_lock); | |
4732 | ||
4733 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4734 | } | |
4735 | ||
4f271a2a VN |
4736 | static ssize_t |
4737 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
4738 | size_t cnt, loff_t *ppos) | |
4739 | { | |
4740 | /* | |
4741 | * There is no need to read what the user has written, this function | |
4742 | * is just to make sure that there is no error when "echo" is used | |
4743 | */ | |
4744 | ||
4745 | *ppos += cnt; | |
a98a3c3f SR |
4746 | |
4747 | return cnt; | |
4748 | } | |
4749 | ||
4f271a2a VN |
4750 | static int |
4751 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
4752 | { | |
2b6080f2 SR |
4753 | struct trace_array *tr = inode->i_private; |
4754 | ||
cf30cf67 SR |
4755 | /* disable tracing ? */ |
4756 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
711e1243 | 4757 | tracer_tracing_off(tr); |
4f271a2a | 4758 | /* resize the ring buffer to 0 */ |
2b6080f2 | 4759 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 4760 | |
7b85af63 SRRH |
4761 | trace_array_put(tr); |
4762 | ||
4f271a2a VN |
4763 | return 0; |
4764 | } | |
4765 | ||
5bf9a1ee PP |
4766 | static ssize_t |
4767 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
4768 | size_t cnt, loff_t *fpos) | |
4769 | { | |
d696b58c | 4770 | unsigned long addr = (unsigned long)ubuf; |
2d71619c | 4771 | struct trace_array *tr = filp->private_data; |
d696b58c SR |
4772 | struct ring_buffer_event *event; |
4773 | struct ring_buffer *buffer; | |
4774 | struct print_entry *entry; | |
4775 | unsigned long irq_flags; | |
4776 | struct page *pages[2]; | |
6edb2a8a | 4777 | void *map_page[2]; |
d696b58c SR |
4778 | int nr_pages = 1; |
4779 | ssize_t written; | |
d696b58c SR |
4780 | int offset; |
4781 | int size; | |
4782 | int len; | |
4783 | int ret; | |
6edb2a8a | 4784 | int i; |
5bf9a1ee | 4785 | |
c76f0694 | 4786 | if (tracing_disabled) |
5bf9a1ee PP |
4787 | return -EINVAL; |
4788 | ||
5224c3a3 MSB |
4789 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
4790 | return -EINVAL; | |
4791 | ||
5bf9a1ee PP |
4792 | if (cnt > TRACE_BUF_SIZE) |
4793 | cnt = TRACE_BUF_SIZE; | |
4794 | ||
d696b58c SR |
4795 | /* |
4796 | * Userspace is injecting traces into the kernel trace buffer. | |
4797 | * We want to be as non intrusive as possible. | |
4798 | * To do so, we do not want to allocate any special buffers | |
4799 | * or take any locks, but instead write the userspace data | |
4800 | * straight into the ring buffer. | |
4801 | * | |
4802 | * First we need to pin the userspace buffer into memory, | |
4803 | * which, most likely it is, because it just referenced it. | |
4804 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
4805 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
4806 | * pages directly. We then write the data directly into the | |
4807 | * ring buffer. | |
4808 | */ | |
4809 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 4810 | |
d696b58c SR |
4811 | /* check if we cross pages */ |
4812 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
4813 | nr_pages = 2; | |
4814 | ||
4815 | offset = addr & (PAGE_SIZE - 1); | |
4816 | addr &= PAGE_MASK; | |
4817 | ||
4818 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
4819 | if (ret < nr_pages) { | |
4820 | while (--ret >= 0) | |
4821 | put_page(pages[ret]); | |
4822 | written = -EFAULT; | |
4823 | goto out; | |
5bf9a1ee | 4824 | } |
d696b58c | 4825 | |
6edb2a8a SR |
4826 | for (i = 0; i < nr_pages; i++) |
4827 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
4828 | |
4829 | local_save_flags(irq_flags); | |
4830 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
2d71619c | 4831 | buffer = tr->trace_buffer.buffer; |
d696b58c SR |
4832 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
4833 | irq_flags, preempt_count()); | |
4834 | if (!event) { | |
4835 | /* Ring buffer disabled, return as if not open for write */ | |
4836 | written = -EBADF; | |
4837 | goto out_unlock; | |
5bf9a1ee | 4838 | } |
d696b58c SR |
4839 | |
4840 | entry = ring_buffer_event_data(event); | |
4841 | entry->ip = _THIS_IP_; | |
4842 | ||
4843 | if (nr_pages == 2) { | |
4844 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
4845 | memcpy(&entry->buf, map_page[0] + offset, len); |
4846 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 4847 | } else |
6edb2a8a | 4848 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 4849 | |
d696b58c SR |
4850 | if (entry->buf[cnt - 1] != '\n') { |
4851 | entry->buf[cnt] = '\n'; | |
4852 | entry->buf[cnt + 1] = '\0'; | |
4853 | } else | |
4854 | entry->buf[cnt] = '\0'; | |
4855 | ||
7ffbd48d | 4856 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 4857 | |
d696b58c | 4858 | written = cnt; |
5bf9a1ee | 4859 | |
d696b58c | 4860 | *fpos += written; |
1aa54bca | 4861 | |
d696b58c | 4862 | out_unlock: |
6edb2a8a SR |
4863 | for (i = 0; i < nr_pages; i++){ |
4864 | kunmap_atomic(map_page[i]); | |
4865 | put_page(pages[i]); | |
4866 | } | |
d696b58c | 4867 | out: |
1aa54bca | 4868 | return written; |
5bf9a1ee PP |
4869 | } |
4870 | ||
13f16d20 | 4871 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 4872 | { |
2b6080f2 | 4873 | struct trace_array *tr = m->private; |
5079f326 Z |
4874 | int i; |
4875 | ||
4876 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 4877 | seq_printf(m, |
5079f326 | 4878 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
4879 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
4880 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 4881 | seq_putc(m, '\n'); |
5079f326 | 4882 | |
13f16d20 | 4883 | return 0; |
5079f326 Z |
4884 | } |
4885 | ||
e1e232ca | 4886 | static int tracing_set_clock(struct trace_array *tr, const char *clockstr) |
5079f326 | 4887 | { |
5079f326 Z |
4888 | int i; |
4889 | ||
5079f326 Z |
4890 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { |
4891 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
4892 | break; | |
4893 | } | |
4894 | if (i == ARRAY_SIZE(trace_clocks)) | |
4895 | return -EINVAL; | |
4896 | ||
5079f326 Z |
4897 | mutex_lock(&trace_types_lock); |
4898 | ||
2b6080f2 SR |
4899 | tr->clock_id = i; |
4900 | ||
12883efb | 4901 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 4902 | |
60303ed3 DS |
4903 | /* |
4904 | * New clock may not be consistent with the previous clock. | |
4905 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
4906 | */ | |
9457158b | 4907 | tracing_reset_online_cpus(&tr->trace_buffer); |
12883efb SRRH |
4908 | |
4909 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4910 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) | |
4911 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); | |
9457158b | 4912 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 4913 | #endif |
60303ed3 | 4914 | |
5079f326 Z |
4915 | mutex_unlock(&trace_types_lock); |
4916 | ||
e1e232ca SR |
4917 | return 0; |
4918 | } | |
4919 | ||
4920 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
4921 | size_t cnt, loff_t *fpos) | |
4922 | { | |
4923 | struct seq_file *m = filp->private_data; | |
4924 | struct trace_array *tr = m->private; | |
4925 | char buf[64]; | |
4926 | const char *clockstr; | |
4927 | int ret; | |
4928 | ||
4929 | if (cnt >= sizeof(buf)) | |
4930 | return -EINVAL; | |
4931 | ||
4932 | if (copy_from_user(&buf, ubuf, cnt)) | |
4933 | return -EFAULT; | |
4934 | ||
4935 | buf[cnt] = 0; | |
4936 | ||
4937 | clockstr = strstrip(buf); | |
4938 | ||
4939 | ret = tracing_set_clock(tr, clockstr); | |
4940 | if (ret) | |
4941 | return ret; | |
4942 | ||
5079f326 Z |
4943 | *fpos += cnt; |
4944 | ||
4945 | return cnt; | |
4946 | } | |
4947 | ||
13f16d20 LZ |
4948 | static int tracing_clock_open(struct inode *inode, struct file *file) |
4949 | { | |
7b85af63 SRRH |
4950 | struct trace_array *tr = inode->i_private; |
4951 | int ret; | |
4952 | ||
13f16d20 LZ |
4953 | if (tracing_disabled) |
4954 | return -ENODEV; | |
2b6080f2 | 4955 | |
7b85af63 SRRH |
4956 | if (trace_array_get(tr)) |
4957 | return -ENODEV; | |
4958 | ||
4959 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
4960 | if (ret < 0) | |
4961 | trace_array_put(tr); | |
4962 | ||
4963 | return ret; | |
13f16d20 LZ |
4964 | } |
4965 | ||
6de58e62 SRRH |
4966 | struct ftrace_buffer_info { |
4967 | struct trace_iterator iter; | |
4968 | void *spare; | |
4969 | unsigned int read; | |
4970 | }; | |
4971 | ||
debdd57f HT |
4972 | #ifdef CONFIG_TRACER_SNAPSHOT |
4973 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
4974 | { | |
6484c71c | 4975 | struct trace_array *tr = inode->i_private; |
debdd57f | 4976 | struct trace_iterator *iter; |
2b6080f2 | 4977 | struct seq_file *m; |
debdd57f HT |
4978 | int ret = 0; |
4979 | ||
ff451961 SRRH |
4980 | if (trace_array_get(tr) < 0) |
4981 | return -ENODEV; | |
4982 | ||
debdd57f | 4983 | if (file->f_mode & FMODE_READ) { |
6484c71c | 4984 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
4985 | if (IS_ERR(iter)) |
4986 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
4987 | } else { |
4988 | /* Writes still need the seq_file to hold the private data */ | |
f77d09a3 | 4989 | ret = -ENOMEM; |
2b6080f2 SR |
4990 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
4991 | if (!m) | |
f77d09a3 | 4992 | goto out; |
2b6080f2 SR |
4993 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
4994 | if (!iter) { | |
4995 | kfree(m); | |
f77d09a3 | 4996 | goto out; |
2b6080f2 | 4997 | } |
f77d09a3 AL |
4998 | ret = 0; |
4999 | ||
ff451961 | 5000 | iter->tr = tr; |
6484c71c ON |
5001 | iter->trace_buffer = &tr->max_buffer; |
5002 | iter->cpu_file = tracing_get_cpu(inode); | |
2b6080f2 SR |
5003 | m->private = iter; |
5004 | file->private_data = m; | |
debdd57f | 5005 | } |
f77d09a3 | 5006 | out: |
ff451961 SRRH |
5007 | if (ret < 0) |
5008 | trace_array_put(tr); | |
5009 | ||
debdd57f HT |
5010 | return ret; |
5011 | } | |
5012 | ||
5013 | static ssize_t | |
5014 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5015 | loff_t *ppos) | |
5016 | { | |
2b6080f2 SR |
5017 | struct seq_file *m = filp->private_data; |
5018 | struct trace_iterator *iter = m->private; | |
5019 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
5020 | unsigned long val; |
5021 | int ret; | |
5022 | ||
5023 | ret = tracing_update_buffers(); | |
5024 | if (ret < 0) | |
5025 | return ret; | |
5026 | ||
5027 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5028 | if (ret) | |
5029 | return ret; | |
5030 | ||
5031 | mutex_lock(&trace_types_lock); | |
5032 | ||
2b6080f2 | 5033 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
5034 | ret = -EBUSY; |
5035 | goto out; | |
5036 | } | |
5037 | ||
5038 | switch (val) { | |
5039 | case 0: | |
f1affcaa SRRH |
5040 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
5041 | ret = -EINVAL; | |
5042 | break; | |
debdd57f | 5043 | } |
3209cff4 SRRH |
5044 | if (tr->allocated_snapshot) |
5045 | free_snapshot(tr); | |
debdd57f HT |
5046 | break; |
5047 | case 1: | |
f1affcaa SRRH |
5048 | /* Only allow per-cpu swap if the ring buffer supports it */ |
5049 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
5050 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
5051 | ret = -EINVAL; | |
5052 | break; | |
5053 | } | |
5054 | #endif | |
45ad21ca | 5055 | if (!tr->allocated_snapshot) { |
3209cff4 | 5056 | ret = alloc_snapshot(tr); |
debdd57f HT |
5057 | if (ret < 0) |
5058 | break; | |
debdd57f | 5059 | } |
debdd57f HT |
5060 | local_irq_disable(); |
5061 | /* Now, we're going to swap */ | |
f1affcaa | 5062 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 5063 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 5064 | else |
ce9bae55 | 5065 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
5066 | local_irq_enable(); |
5067 | break; | |
5068 | default: | |
45ad21ca | 5069 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
5070 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
5071 | tracing_reset_online_cpus(&tr->max_buffer); | |
5072 | else | |
5073 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
5074 | } | |
debdd57f HT |
5075 | break; |
5076 | } | |
5077 | ||
5078 | if (ret >= 0) { | |
5079 | *ppos += cnt; | |
5080 | ret = cnt; | |
5081 | } | |
5082 | out: | |
5083 | mutex_unlock(&trace_types_lock); | |
5084 | return ret; | |
5085 | } | |
2b6080f2 SR |
5086 | |
5087 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
5088 | { | |
5089 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
5090 | int ret; |
5091 | ||
5092 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
5093 | |
5094 | if (file->f_mode & FMODE_READ) | |
ff451961 | 5095 | return ret; |
2b6080f2 SR |
5096 | |
5097 | /* If write only, the seq_file is just a stub */ | |
5098 | if (m) | |
5099 | kfree(m->private); | |
5100 | kfree(m); | |
5101 | ||
5102 | return 0; | |
5103 | } | |
5104 | ||
6de58e62 SRRH |
5105 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
5106 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5107 | size_t count, loff_t *ppos); | |
5108 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
5109 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5110 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
5111 | ||
5112 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
5113 | { | |
5114 | struct ftrace_buffer_info *info; | |
5115 | int ret; | |
5116 | ||
5117 | ret = tracing_buffers_open(inode, filp); | |
5118 | if (ret < 0) | |
5119 | return ret; | |
5120 | ||
5121 | info = filp->private_data; | |
5122 | ||
5123 | if (info->iter.trace->use_max_tr) { | |
5124 | tracing_buffers_release(inode, filp); | |
5125 | return -EBUSY; | |
5126 | } | |
5127 | ||
5128 | info->iter.snapshot = true; | |
5129 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
5130 | ||
5131 | return ret; | |
5132 | } | |
5133 | ||
debdd57f HT |
5134 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5135 | ||
5136 | ||
5e2336a0 | 5137 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
5138 | .open = tracing_open_generic, |
5139 | .read = tracing_max_lat_read, | |
5140 | .write = tracing_max_lat_write, | |
b444786f | 5141 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5142 | }; |
5143 | ||
5e2336a0 | 5144 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
5145 | .open = tracing_open_generic, |
5146 | .read = tracing_set_trace_read, | |
5147 | .write = tracing_set_trace_write, | |
b444786f | 5148 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5149 | }; |
5150 | ||
5e2336a0 | 5151 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 5152 | .open = tracing_open_pipe, |
2a2cc8f7 | 5153 | .poll = tracing_poll_pipe, |
4bf39a94 | 5154 | .read = tracing_read_pipe, |
3c56819b | 5155 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 5156 | .release = tracing_release_pipe, |
b444786f | 5157 | .llseek = no_llseek, |
b3806b43 SR |
5158 | }; |
5159 | ||
5e2336a0 | 5160 | static const struct file_operations tracing_entries_fops = { |
0bc392ee | 5161 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
5162 | .read = tracing_entries_read, |
5163 | .write = tracing_entries_write, | |
b444786f | 5164 | .llseek = generic_file_llseek, |
0bc392ee | 5165 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
5166 | }; |
5167 | ||
f81ab074 | 5168 | static const struct file_operations tracing_total_entries_fops = { |
7b85af63 | 5169 | .open = tracing_open_generic_tr, |
f81ab074 VN |
5170 | .read = tracing_total_entries_read, |
5171 | .llseek = generic_file_llseek, | |
7b85af63 | 5172 | .release = tracing_release_generic_tr, |
f81ab074 VN |
5173 | }; |
5174 | ||
4f271a2a | 5175 | static const struct file_operations tracing_free_buffer_fops = { |
7b85af63 | 5176 | .open = tracing_open_generic_tr, |
4f271a2a VN |
5177 | .write = tracing_free_buffer_write, |
5178 | .release = tracing_free_buffer_release, | |
5179 | }; | |
5180 | ||
5e2336a0 | 5181 | static const struct file_operations tracing_mark_fops = { |
7b85af63 | 5182 | .open = tracing_open_generic_tr, |
5bf9a1ee | 5183 | .write = tracing_mark_write, |
b444786f | 5184 | .llseek = generic_file_llseek, |
7b85af63 | 5185 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
5186 | }; |
5187 | ||
5079f326 | 5188 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
5189 | .open = tracing_clock_open, |
5190 | .read = seq_read, | |
5191 | .llseek = seq_lseek, | |
7b85af63 | 5192 | .release = tracing_single_release_tr, |
5079f326 Z |
5193 | .write = tracing_clock_write, |
5194 | }; | |
5195 | ||
debdd57f HT |
5196 | #ifdef CONFIG_TRACER_SNAPSHOT |
5197 | static const struct file_operations snapshot_fops = { | |
5198 | .open = tracing_snapshot_open, | |
5199 | .read = seq_read, | |
5200 | .write = tracing_snapshot_write, | |
098c879e | 5201 | .llseek = tracing_lseek, |
2b6080f2 | 5202 | .release = tracing_snapshot_release, |
debdd57f | 5203 | }; |
debdd57f | 5204 | |
6de58e62 SRRH |
5205 | static const struct file_operations snapshot_raw_fops = { |
5206 | .open = snapshot_raw_open, | |
5207 | .read = tracing_buffers_read, | |
5208 | .release = tracing_buffers_release, | |
5209 | .splice_read = tracing_buffers_splice_read, | |
5210 | .llseek = no_llseek, | |
2cadf913 SR |
5211 | }; |
5212 | ||
6de58e62 SRRH |
5213 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5214 | ||
2cadf913 SR |
5215 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
5216 | { | |
46ef2be0 | 5217 | struct trace_array *tr = inode->i_private; |
2cadf913 | 5218 | struct ftrace_buffer_info *info; |
7b85af63 | 5219 | int ret; |
2cadf913 SR |
5220 | |
5221 | if (tracing_disabled) | |
5222 | return -ENODEV; | |
5223 | ||
7b85af63 SRRH |
5224 | if (trace_array_get(tr) < 0) |
5225 | return -ENODEV; | |
5226 | ||
2cadf913 | 5227 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
7b85af63 SRRH |
5228 | if (!info) { |
5229 | trace_array_put(tr); | |
2cadf913 | 5230 | return -ENOMEM; |
7b85af63 | 5231 | } |
2cadf913 | 5232 | |
a695cb58 SRRH |
5233 | mutex_lock(&trace_types_lock); |
5234 | ||
cc60cdc9 | 5235 | info->iter.tr = tr; |
46ef2be0 | 5236 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 5237 | info->iter.trace = tr->current_trace; |
12883efb | 5238 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 5239 | info->spare = NULL; |
2cadf913 | 5240 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 5241 | info->read = (unsigned int)-1; |
2cadf913 SR |
5242 | |
5243 | filp->private_data = info; | |
5244 | ||
a695cb58 SRRH |
5245 | mutex_unlock(&trace_types_lock); |
5246 | ||
7b85af63 SRRH |
5247 | ret = nonseekable_open(inode, filp); |
5248 | if (ret < 0) | |
5249 | trace_array_put(tr); | |
5250 | ||
5251 | return ret; | |
2cadf913 SR |
5252 | } |
5253 | ||
cc60cdc9 SR |
5254 | static unsigned int |
5255 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
5256 | { | |
5257 | struct ftrace_buffer_info *info = filp->private_data; | |
5258 | struct trace_iterator *iter = &info->iter; | |
5259 | ||
5260 | return trace_poll(iter, filp, poll_table); | |
5261 | } | |
5262 | ||
2cadf913 SR |
5263 | static ssize_t |
5264 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5265 | size_t count, loff_t *ppos) | |
5266 | { | |
5267 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 5268 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5269 | ssize_t ret; |
6de58e62 | 5270 | ssize_t size; |
2cadf913 | 5271 | |
2dc5d12b SR |
5272 | if (!count) |
5273 | return 0; | |
5274 | ||
6de58e62 SRRH |
5275 | mutex_lock(&trace_types_lock); |
5276 | ||
5277 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5278 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
5279 | size = -EBUSY; | |
5280 | goto out_unlock; | |
5281 | } | |
5282 | #endif | |
5283 | ||
ddd538f3 | 5284 | if (!info->spare) |
12883efb SRRH |
5285 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
5286 | iter->cpu_file); | |
6de58e62 | 5287 | size = -ENOMEM; |
ddd538f3 | 5288 | if (!info->spare) |
6de58e62 | 5289 | goto out_unlock; |
ddd538f3 | 5290 | |
2cadf913 SR |
5291 | /* Do we have previous read data to read? */ |
5292 | if (info->read < PAGE_SIZE) | |
5293 | goto read; | |
5294 | ||
b627344f | 5295 | again: |
cc60cdc9 | 5296 | trace_access_lock(iter->cpu_file); |
12883efb | 5297 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
5298 | &info->spare, |
5299 | count, | |
cc60cdc9 SR |
5300 | iter->cpu_file, 0); |
5301 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 5302 | |
b627344f SR |
5303 | if (ret < 0) { |
5304 | if (trace_empty(iter)) { | |
6de58e62 SRRH |
5305 | if ((filp->f_flags & O_NONBLOCK)) { |
5306 | size = -EAGAIN; | |
5307 | goto out_unlock; | |
5308 | } | |
5309 | mutex_unlock(&trace_types_lock); | |
8b8b3683 | 5310 | ret = wait_on_pipe(iter); |
6de58e62 | 5311 | mutex_lock(&trace_types_lock); |
8b8b3683 SRRH |
5312 | if (ret) { |
5313 | size = ret; | |
5314 | goto out_unlock; | |
5315 | } | |
6de58e62 SRRH |
5316 | if (signal_pending(current)) { |
5317 | size = -EINTR; | |
5318 | goto out_unlock; | |
5319 | } | |
b627344f SR |
5320 | goto again; |
5321 | } | |
6de58e62 SRRH |
5322 | size = 0; |
5323 | goto out_unlock; | |
b627344f | 5324 | } |
436fc280 | 5325 | |
436fc280 | 5326 | info->read = 0; |
b627344f | 5327 | read: |
2cadf913 SR |
5328 | size = PAGE_SIZE - info->read; |
5329 | if (size > count) | |
5330 | size = count; | |
5331 | ||
5332 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
6de58e62 SRRH |
5333 | if (ret == size) { |
5334 | size = -EFAULT; | |
5335 | goto out_unlock; | |
5336 | } | |
2dc5d12b SR |
5337 | size -= ret; |
5338 | ||
2cadf913 SR |
5339 | *ppos += size; |
5340 | info->read += size; | |
5341 | ||
6de58e62 SRRH |
5342 | out_unlock: |
5343 | mutex_unlock(&trace_types_lock); | |
5344 | ||
2cadf913 SR |
5345 | return size; |
5346 | } | |
5347 | ||
5348 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
5349 | { | |
5350 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5351 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5352 | |
a695cb58 SRRH |
5353 | mutex_lock(&trace_types_lock); |
5354 | ||
ff451961 | 5355 | __trace_array_put(iter->tr); |
2cadf913 | 5356 | |
ddd538f3 | 5357 | if (info->spare) |
12883efb | 5358 | ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); |
2cadf913 SR |
5359 | kfree(info); |
5360 | ||
a695cb58 SRRH |
5361 | mutex_unlock(&trace_types_lock); |
5362 | ||
2cadf913 SR |
5363 | return 0; |
5364 | } | |
5365 | ||
5366 | struct buffer_ref { | |
5367 | struct ring_buffer *buffer; | |
5368 | void *page; | |
5369 | int ref; | |
5370 | }; | |
5371 | ||
5372 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
5373 | struct pipe_buffer *buf) | |
5374 | { | |
5375 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5376 | ||
5377 | if (--ref->ref) | |
5378 | return; | |
5379 | ||
5380 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5381 | kfree(ref); | |
5382 | buf->private = 0; | |
5383 | } | |
5384 | ||
2cadf913 SR |
5385 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
5386 | struct pipe_buffer *buf) | |
5387 | { | |
5388 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5389 | ||
5390 | ref->ref++; | |
5391 | } | |
5392 | ||
5393 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 5394 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 | 5395 | .can_merge = 0, |
2cadf913 SR |
5396 | .confirm = generic_pipe_buf_confirm, |
5397 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 5398 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
5399 | .get = buffer_pipe_buf_get, |
5400 | }; | |
5401 | ||
5402 | /* | |
5403 | * Callback from splice_to_pipe(), if we need to release some pages | |
5404 | * at the end of the spd in case we error'ed out in filling the pipe. | |
5405 | */ | |
5406 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
5407 | { | |
5408 | struct buffer_ref *ref = | |
5409 | (struct buffer_ref *)spd->partial[i].private; | |
5410 | ||
5411 | if (--ref->ref) | |
5412 | return; | |
5413 | ||
5414 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5415 | kfree(ref); | |
5416 | spd->partial[i].private = 0; | |
5417 | } | |
5418 | ||
5419 | static ssize_t | |
5420 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5421 | struct pipe_inode_info *pipe, size_t len, | |
5422 | unsigned int flags) | |
5423 | { | |
5424 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5425 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
5426 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
5427 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 5428 | struct splice_pipe_desc spd = { |
35f3d14d JA |
5429 | .pages = pages_def, |
5430 | .partial = partial_def, | |
047fe360 | 5431 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
5432 | .flags = flags, |
5433 | .ops = &buffer_pipe_buf_ops, | |
5434 | .spd_release = buffer_spd_release, | |
5435 | }; | |
5436 | struct buffer_ref *ref; | |
93459c6c | 5437 | int entries, size, i; |
6de58e62 | 5438 | ssize_t ret; |
2cadf913 | 5439 | |
6de58e62 SRRH |
5440 | mutex_lock(&trace_types_lock); |
5441 | ||
5442 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5443 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
5444 | ret = -EBUSY; | |
5445 | goto out; | |
5446 | } | |
5447 | #endif | |
5448 | ||
5449 | if (splice_grow_spd(pipe, &spd)) { | |
5450 | ret = -ENOMEM; | |
5451 | goto out; | |
5452 | } | |
35f3d14d | 5453 | |
93cfb3c9 | 5454 | if (*ppos & (PAGE_SIZE - 1)) { |
35f3d14d JA |
5455 | ret = -EINVAL; |
5456 | goto out; | |
93cfb3c9 LJ |
5457 | } |
5458 | ||
5459 | if (len & (PAGE_SIZE - 1)) { | |
35f3d14d JA |
5460 | if (len < PAGE_SIZE) { |
5461 | ret = -EINVAL; | |
5462 | goto out; | |
5463 | } | |
93cfb3c9 LJ |
5464 | len &= PAGE_MASK; |
5465 | } | |
5466 | ||
cc60cdc9 SR |
5467 | again: |
5468 | trace_access_lock(iter->cpu_file); | |
12883efb | 5469 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 5470 | |
a786c06d | 5471 | for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
5472 | struct page *page; |
5473 | int r; | |
5474 | ||
5475 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
5476 | if (!ref) | |
5477 | break; | |
5478 | ||
7267fa68 | 5479 | ref->ref = 1; |
12883efb | 5480 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 5481 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
2cadf913 SR |
5482 | if (!ref->page) { |
5483 | kfree(ref); | |
5484 | break; | |
5485 | } | |
5486 | ||
5487 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 5488 | len, iter->cpu_file, 1); |
2cadf913 | 5489 | if (r < 0) { |
7ea59064 | 5490 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
5491 | kfree(ref); |
5492 | break; | |
5493 | } | |
5494 | ||
5495 | /* | |
5496 | * zero out any left over data, this is going to | |
5497 | * user land. | |
5498 | */ | |
5499 | size = ring_buffer_page_len(ref->page); | |
5500 | if (size < PAGE_SIZE) | |
5501 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
5502 | ||
5503 | page = virt_to_page(ref->page); | |
5504 | ||
5505 | spd.pages[i] = page; | |
5506 | spd.partial[i].len = PAGE_SIZE; | |
5507 | spd.partial[i].offset = 0; | |
5508 | spd.partial[i].private = (unsigned long)ref; | |
5509 | spd.nr_pages++; | |
93cfb3c9 | 5510 | *ppos += PAGE_SIZE; |
93459c6c | 5511 | |
12883efb | 5512 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
5513 | } |
5514 | ||
cc60cdc9 | 5515 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
5516 | spd.nr_pages = i; |
5517 | ||
5518 | /* did we read anything? */ | |
5519 | if (!spd.nr_pages) { | |
cc60cdc9 | 5520 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) { |
2cadf913 | 5521 | ret = -EAGAIN; |
cc60cdc9 SR |
5522 | goto out; |
5523 | } | |
6de58e62 | 5524 | mutex_unlock(&trace_types_lock); |
8b8b3683 | 5525 | ret = wait_on_pipe(iter); |
6de58e62 | 5526 | mutex_lock(&trace_types_lock); |
8b8b3683 SRRH |
5527 | if (ret) |
5528 | goto out; | |
cc60cdc9 SR |
5529 | if (signal_pending(current)) { |
5530 | ret = -EINTR; | |
5531 | goto out; | |
5532 | } | |
5533 | goto again; | |
2cadf913 SR |
5534 | } |
5535 | ||
5536 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 5537 | splice_shrink_spd(&spd); |
35f3d14d | 5538 | out: |
6de58e62 SRRH |
5539 | mutex_unlock(&trace_types_lock); |
5540 | ||
2cadf913 SR |
5541 | return ret; |
5542 | } | |
5543 | ||
5544 | static const struct file_operations tracing_buffers_fops = { | |
5545 | .open = tracing_buffers_open, | |
5546 | .read = tracing_buffers_read, | |
cc60cdc9 | 5547 | .poll = tracing_buffers_poll, |
2cadf913 SR |
5548 | .release = tracing_buffers_release, |
5549 | .splice_read = tracing_buffers_splice_read, | |
5550 | .llseek = no_llseek, | |
5551 | }; | |
5552 | ||
c8d77183 SR |
5553 | static ssize_t |
5554 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
5555 | size_t count, loff_t *ppos) | |
5556 | { | |
4d3435b8 ON |
5557 | struct inode *inode = file_inode(filp); |
5558 | struct trace_array *tr = inode->i_private; | |
12883efb | 5559 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
4d3435b8 | 5560 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
5561 | struct trace_seq *s; |
5562 | unsigned long cnt; | |
c64e148a VN |
5563 | unsigned long long t; |
5564 | unsigned long usec_rem; | |
c8d77183 | 5565 | |
e4f2d10f | 5566 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 5567 | if (!s) |
a646365c | 5568 | return -ENOMEM; |
c8d77183 SR |
5569 | |
5570 | trace_seq_init(s); | |
5571 | ||
12883efb | 5572 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5573 | trace_seq_printf(s, "entries: %ld\n", cnt); |
5574 | ||
12883efb | 5575 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5576 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
5577 | ||
12883efb | 5578 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5579 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
5580 | ||
12883efb | 5581 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
5582 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
5583 | ||
58e8eedf | 5584 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 5585 | /* local or global for trace_clock */ |
12883efb | 5586 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
5587 | usec_rem = do_div(t, USEC_PER_SEC); |
5588 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
5589 | t, usec_rem); | |
5590 | ||
12883efb | 5591 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
5592 | usec_rem = do_div(t, USEC_PER_SEC); |
5593 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
5594 | } else { | |
5595 | /* counter or tsc mode for trace_clock */ | |
5596 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 5597 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 5598 | |
11043d8b | 5599 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 5600 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 5601 | } |
c64e148a | 5602 | |
12883efb | 5603 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
5604 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
5605 | ||
12883efb | 5606 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
5607 | trace_seq_printf(s, "read events: %ld\n", cnt); |
5608 | ||
c8d77183 SR |
5609 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
5610 | ||
5611 | kfree(s); | |
5612 | ||
5613 | return count; | |
5614 | } | |
5615 | ||
5616 | static const struct file_operations tracing_stats_fops = { | |
4d3435b8 | 5617 | .open = tracing_open_generic_tr, |
c8d77183 | 5618 | .read = tracing_stats_read, |
b444786f | 5619 | .llseek = generic_file_llseek, |
4d3435b8 | 5620 | .release = tracing_release_generic_tr, |
c8d77183 SR |
5621 | }; |
5622 | ||
bc0c38d1 SR |
5623 | #ifdef CONFIG_DYNAMIC_FTRACE |
5624 | ||
b807c3d0 SR |
5625 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
5626 | { | |
5627 | return 0; | |
5628 | } | |
5629 | ||
bc0c38d1 | 5630 | static ssize_t |
b807c3d0 | 5631 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
5632 | size_t cnt, loff_t *ppos) |
5633 | { | |
a26a2a27 SR |
5634 | static char ftrace_dyn_info_buffer[1024]; |
5635 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 5636 | unsigned long *p = filp->private_data; |
b807c3d0 | 5637 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 5638 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
5639 | int r; |
5640 | ||
b807c3d0 SR |
5641 | mutex_lock(&dyn_info_mutex); |
5642 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 5643 | |
a26a2a27 | 5644 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
5645 | buf[r++] = '\n'; |
5646 | ||
5647 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5648 | ||
5649 | mutex_unlock(&dyn_info_mutex); | |
5650 | ||
5651 | return r; | |
bc0c38d1 SR |
5652 | } |
5653 | ||
5e2336a0 | 5654 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 5655 | .open = tracing_open_generic, |
b807c3d0 | 5656 | .read = tracing_read_dyn_info, |
b444786f | 5657 | .llseek = generic_file_llseek, |
bc0c38d1 | 5658 | }; |
77fd5c15 | 5659 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 5660 | |
77fd5c15 SRRH |
5661 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
5662 | static void | |
5663 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
5664 | { | |
5665 | tracing_snapshot(); | |
5666 | } | |
bc0c38d1 | 5667 | |
77fd5c15 SRRH |
5668 | static void |
5669 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
bc0c38d1 | 5670 | { |
77fd5c15 SRRH |
5671 | unsigned long *count = (long *)data; |
5672 | ||
5673 | if (!*count) | |
5674 | return; | |
bc0c38d1 | 5675 | |
77fd5c15 SRRH |
5676 | if (*count != -1) |
5677 | (*count)--; | |
5678 | ||
5679 | tracing_snapshot(); | |
5680 | } | |
5681 | ||
5682 | static int | |
5683 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
5684 | struct ftrace_probe_ops *ops, void *data) | |
5685 | { | |
5686 | long count = (long)data; | |
5687 | ||
5688 | seq_printf(m, "%ps:", (void *)ip); | |
5689 | ||
5690 | seq_printf(m, "snapshot"); | |
5691 | ||
5692 | if (count == -1) | |
5693 | seq_printf(m, ":unlimited\n"); | |
5694 | else | |
5695 | seq_printf(m, ":count=%ld\n", count); | |
5696 | ||
5697 | return 0; | |
5698 | } | |
5699 | ||
5700 | static struct ftrace_probe_ops snapshot_probe_ops = { | |
5701 | .func = ftrace_snapshot, | |
5702 | .print = ftrace_snapshot_print, | |
5703 | }; | |
5704 | ||
5705 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
5706 | .func = ftrace_count_snapshot, | |
5707 | .print = ftrace_snapshot_print, | |
5708 | }; | |
5709 | ||
5710 | static int | |
5711 | ftrace_trace_snapshot_callback(struct ftrace_hash *hash, | |
5712 | char *glob, char *cmd, char *param, int enable) | |
5713 | { | |
5714 | struct ftrace_probe_ops *ops; | |
5715 | void *count = (void *)-1; | |
5716 | char *number; | |
5717 | int ret; | |
5718 | ||
5719 | /* hash funcs only work with set_ftrace_filter */ | |
5720 | if (!enable) | |
5721 | return -EINVAL; | |
5722 | ||
5723 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
5724 | ||
5725 | if (glob[0] == '!') { | |
5726 | unregister_ftrace_function_probe_func(glob+1, ops); | |
5727 | return 0; | |
5728 | } | |
5729 | ||
5730 | if (!param) | |
5731 | goto out_reg; | |
5732 | ||
5733 | number = strsep(¶m, ":"); | |
5734 | ||
5735 | if (!strlen(number)) | |
5736 | goto out_reg; | |
5737 | ||
5738 | /* | |
5739 | * We use the callback data field (which is a pointer) | |
5740 | * as our counter. | |
5741 | */ | |
5742 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
5743 | if (ret) | |
5744 | return ret; | |
5745 | ||
5746 | out_reg: | |
5747 | ret = register_ftrace_function_probe(glob, ops, count); | |
5748 | ||
5749 | if (ret >= 0) | |
5750 | alloc_snapshot(&global_trace); | |
5751 | ||
5752 | return ret < 0 ? ret : 0; | |
5753 | } | |
5754 | ||
5755 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
5756 | .name = "snapshot", | |
5757 | .func = ftrace_trace_snapshot_callback, | |
5758 | }; | |
5759 | ||
38de93ab | 5760 | static __init int register_snapshot_cmd(void) |
77fd5c15 SRRH |
5761 | { |
5762 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
5763 | } | |
5764 | #else | |
38de93ab | 5765 | static inline __init int register_snapshot_cmd(void) { return 0; } |
77fd5c15 | 5766 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ |
bc0c38d1 | 5767 | |
2b6080f2 | 5768 | struct dentry *tracing_init_dentry_tr(struct trace_array *tr) |
bc0c38d1 | 5769 | { |
2b6080f2 SR |
5770 | if (tr->dir) |
5771 | return tr->dir; | |
bc0c38d1 | 5772 | |
3e1f60b8 FW |
5773 | if (!debugfs_initialized()) |
5774 | return NULL; | |
5775 | ||
2b6080f2 SR |
5776 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) |
5777 | tr->dir = debugfs_create_dir("tracing", NULL); | |
bc0c38d1 | 5778 | |
687c878a J |
5779 | if (!tr->dir) |
5780 | pr_warn_once("Could not create debugfs directory 'tracing'\n"); | |
bc0c38d1 | 5781 | |
2b6080f2 | 5782 | return tr->dir; |
bc0c38d1 SR |
5783 | } |
5784 | ||
2b6080f2 SR |
5785 | struct dentry *tracing_init_dentry(void) |
5786 | { | |
5787 | return tracing_init_dentry_tr(&global_trace); | |
5788 | } | |
b04cc6b1 | 5789 | |
2b6080f2 | 5790 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 5791 | { |
b04cc6b1 FW |
5792 | struct dentry *d_tracer; |
5793 | ||
2b6080f2 SR |
5794 | if (tr->percpu_dir) |
5795 | return tr->percpu_dir; | |
b04cc6b1 | 5796 | |
2b6080f2 | 5797 | d_tracer = tracing_init_dentry_tr(tr); |
b04cc6b1 FW |
5798 | if (!d_tracer) |
5799 | return NULL; | |
5800 | ||
2b6080f2 | 5801 | tr->percpu_dir = debugfs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 5802 | |
2b6080f2 SR |
5803 | WARN_ONCE(!tr->percpu_dir, |
5804 | "Could not create debugfs directory 'per_cpu/%d'\n", cpu); | |
b04cc6b1 | 5805 | |
2b6080f2 | 5806 | return tr->percpu_dir; |
b04cc6b1 FW |
5807 | } |
5808 | ||
649e9c70 ON |
5809 | static struct dentry * |
5810 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
5811 | void *data, long cpu, const struct file_operations *fops) | |
5812 | { | |
5813 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
5814 | ||
5815 | if (ret) /* See tracing_get_cpu() */ | |
5816 | ret->d_inode->i_cdev = (void *)(cpu + 1); | |
5817 | return ret; | |
5818 | } | |
5819 | ||
2b6080f2 SR |
5820 | static void |
5821 | tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) | |
b04cc6b1 | 5822 | { |
2b6080f2 | 5823 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 5824 | struct dentry *d_cpu; |
dd49a38c | 5825 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 5826 | |
0a3d7ce7 NK |
5827 | if (!d_percpu) |
5828 | return; | |
5829 | ||
dd49a38c | 5830 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
5831 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
5832 | if (!d_cpu) { | |
5833 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
5834 | return; | |
5835 | } | |
b04cc6b1 | 5836 | |
8656e7a2 | 5837 | /* per cpu trace_pipe */ |
649e9c70 | 5838 | trace_create_cpu_file("trace_pipe", 0444, d_cpu, |
15544209 | 5839 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
5840 | |
5841 | /* per cpu trace */ | |
649e9c70 | 5842 | trace_create_cpu_file("trace", 0644, d_cpu, |
6484c71c | 5843 | tr, cpu, &tracing_fops); |
7f96f93f | 5844 | |
649e9c70 | 5845 | trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, |
46ef2be0 | 5846 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 5847 | |
649e9c70 | 5848 | trace_create_cpu_file("stats", 0444, d_cpu, |
4d3435b8 | 5849 | tr, cpu, &tracing_stats_fops); |
438ced17 | 5850 | |
649e9c70 | 5851 | trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, |
0bc392ee | 5852 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
5853 | |
5854 | #ifdef CONFIG_TRACER_SNAPSHOT | |
649e9c70 | 5855 | trace_create_cpu_file("snapshot", 0644, d_cpu, |
6484c71c | 5856 | tr, cpu, &snapshot_fops); |
6de58e62 | 5857 | |
649e9c70 | 5858 | trace_create_cpu_file("snapshot_raw", 0444, d_cpu, |
46ef2be0 | 5859 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 5860 | #endif |
b04cc6b1 FW |
5861 | } |
5862 | ||
60a11774 SR |
5863 | #ifdef CONFIG_FTRACE_SELFTEST |
5864 | /* Let selftest have access to static functions in this file */ | |
5865 | #include "trace_selftest.c" | |
5866 | #endif | |
5867 | ||
577b785f SR |
5868 | struct trace_option_dentry { |
5869 | struct tracer_opt *opt; | |
5870 | struct tracer_flags *flags; | |
2b6080f2 | 5871 | struct trace_array *tr; |
577b785f SR |
5872 | struct dentry *entry; |
5873 | }; | |
5874 | ||
5875 | static ssize_t | |
5876 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5877 | loff_t *ppos) | |
5878 | { | |
5879 | struct trace_option_dentry *topt = filp->private_data; | |
5880 | char *buf; | |
5881 | ||
5882 | if (topt->flags->val & topt->opt->bit) | |
5883 | buf = "1\n"; | |
5884 | else | |
5885 | buf = "0\n"; | |
5886 | ||
5887 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5888 | } | |
5889 | ||
5890 | static ssize_t | |
5891 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5892 | loff_t *ppos) | |
5893 | { | |
5894 | struct trace_option_dentry *topt = filp->private_data; | |
5895 | unsigned long val; | |
577b785f SR |
5896 | int ret; |
5897 | ||
22fe9b54 PH |
5898 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5899 | if (ret) | |
577b785f SR |
5900 | return ret; |
5901 | ||
8d18eaaf LZ |
5902 | if (val != 0 && val != 1) |
5903 | return -EINVAL; | |
577b785f | 5904 | |
8d18eaaf | 5905 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 5906 | mutex_lock(&trace_types_lock); |
8c1a49ae | 5907 | ret = __set_tracer_option(topt->tr, topt->flags, |
c757bea9 | 5908 | topt->opt, !val); |
577b785f SR |
5909 | mutex_unlock(&trace_types_lock); |
5910 | if (ret) | |
5911 | return ret; | |
577b785f SR |
5912 | } |
5913 | ||
5914 | *ppos += cnt; | |
5915 | ||
5916 | return cnt; | |
5917 | } | |
5918 | ||
5919 | ||
5920 | static const struct file_operations trace_options_fops = { | |
5921 | .open = tracing_open_generic, | |
5922 | .read = trace_options_read, | |
5923 | .write = trace_options_write, | |
b444786f | 5924 | .llseek = generic_file_llseek, |
577b785f SR |
5925 | }; |
5926 | ||
a8259075 SR |
5927 | static ssize_t |
5928 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5929 | loff_t *ppos) | |
5930 | { | |
5931 | long index = (long)filp->private_data; | |
5932 | char *buf; | |
5933 | ||
5934 | if (trace_flags & (1 << index)) | |
5935 | buf = "1\n"; | |
5936 | else | |
5937 | buf = "0\n"; | |
5938 | ||
5939 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5940 | } | |
5941 | ||
5942 | static ssize_t | |
5943 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5944 | loff_t *ppos) | |
5945 | { | |
2b6080f2 | 5946 | struct trace_array *tr = &global_trace; |
a8259075 | 5947 | long index = (long)filp->private_data; |
a8259075 SR |
5948 | unsigned long val; |
5949 | int ret; | |
5950 | ||
22fe9b54 PH |
5951 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5952 | if (ret) | |
a8259075 SR |
5953 | return ret; |
5954 | ||
f2d84b65 | 5955 | if (val != 0 && val != 1) |
a8259075 | 5956 | return -EINVAL; |
69d34da2 SRRH |
5957 | |
5958 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 5959 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 5960 | mutex_unlock(&trace_types_lock); |
a8259075 | 5961 | |
613f04a0 SRRH |
5962 | if (ret < 0) |
5963 | return ret; | |
5964 | ||
a8259075 SR |
5965 | *ppos += cnt; |
5966 | ||
5967 | return cnt; | |
5968 | } | |
5969 | ||
a8259075 SR |
5970 | static const struct file_operations trace_options_core_fops = { |
5971 | .open = tracing_open_generic, | |
5972 | .read = trace_options_core_read, | |
5973 | .write = trace_options_core_write, | |
b444786f | 5974 | .llseek = generic_file_llseek, |
a8259075 SR |
5975 | }; |
5976 | ||
5452af66 | 5977 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 5978 | umode_t mode, |
5452af66 FW |
5979 | struct dentry *parent, |
5980 | void *data, | |
5981 | const struct file_operations *fops) | |
5982 | { | |
5983 | struct dentry *ret; | |
5984 | ||
5985 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
5986 | if (!ret) | |
5987 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
5988 | ||
5989 | return ret; | |
5990 | } | |
5991 | ||
5992 | ||
2b6080f2 | 5993 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
5994 | { |
5995 | struct dentry *d_tracer; | |
a8259075 | 5996 | |
2b6080f2 SR |
5997 | if (tr->options) |
5998 | return tr->options; | |
a8259075 | 5999 | |
2b6080f2 | 6000 | d_tracer = tracing_init_dentry_tr(tr); |
a8259075 SR |
6001 | if (!d_tracer) |
6002 | return NULL; | |
6003 | ||
2b6080f2 SR |
6004 | tr->options = debugfs_create_dir("options", d_tracer); |
6005 | if (!tr->options) { | |
a8259075 SR |
6006 | pr_warning("Could not create debugfs directory 'options'\n"); |
6007 | return NULL; | |
6008 | } | |
6009 | ||
2b6080f2 | 6010 | return tr->options; |
a8259075 SR |
6011 | } |
6012 | ||
577b785f | 6013 | static void |
2b6080f2 SR |
6014 | create_trace_option_file(struct trace_array *tr, |
6015 | struct trace_option_dentry *topt, | |
577b785f SR |
6016 | struct tracer_flags *flags, |
6017 | struct tracer_opt *opt) | |
6018 | { | |
6019 | struct dentry *t_options; | |
577b785f | 6020 | |
2b6080f2 | 6021 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
6022 | if (!t_options) |
6023 | return; | |
6024 | ||
6025 | topt->flags = flags; | |
6026 | topt->opt = opt; | |
2b6080f2 | 6027 | topt->tr = tr; |
577b785f | 6028 | |
5452af66 | 6029 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
6030 | &trace_options_fops); |
6031 | ||
577b785f SR |
6032 | } |
6033 | ||
6034 | static struct trace_option_dentry * | |
2b6080f2 | 6035 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
6036 | { |
6037 | struct trace_option_dentry *topts; | |
6038 | struct tracer_flags *flags; | |
6039 | struct tracer_opt *opts; | |
6040 | int cnt; | |
6041 | ||
6042 | if (!tracer) | |
6043 | return NULL; | |
6044 | ||
6045 | flags = tracer->flags; | |
6046 | ||
6047 | if (!flags || !flags->opts) | |
6048 | return NULL; | |
6049 | ||
6050 | opts = flags->opts; | |
6051 | ||
6052 | for (cnt = 0; opts[cnt].name; cnt++) | |
6053 | ; | |
6054 | ||
0cfe8245 | 6055 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
6056 | if (!topts) |
6057 | return NULL; | |
6058 | ||
6059 | for (cnt = 0; opts[cnt].name; cnt++) | |
2b6080f2 | 6060 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f SR |
6061 | &opts[cnt]); |
6062 | ||
6063 | return topts; | |
6064 | } | |
6065 | ||
6066 | static void | |
6067 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
6068 | { | |
6069 | int cnt; | |
6070 | ||
6071 | if (!topts) | |
6072 | return; | |
6073 | ||
6074 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
6075 | if (topts[cnt].entry) | |
6076 | debugfs_remove(topts[cnt].entry); | |
6077 | } | |
6078 | ||
6079 | kfree(topts); | |
6080 | } | |
6081 | ||
a8259075 | 6082 | static struct dentry * |
2b6080f2 SR |
6083 | create_trace_option_core_file(struct trace_array *tr, |
6084 | const char *option, long index) | |
a8259075 SR |
6085 | { |
6086 | struct dentry *t_options; | |
a8259075 | 6087 | |
2b6080f2 | 6088 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
6089 | if (!t_options) |
6090 | return NULL; | |
6091 | ||
5452af66 | 6092 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 6093 | &trace_options_core_fops); |
a8259075 SR |
6094 | } |
6095 | ||
2b6080f2 | 6096 | static __init void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
6097 | { |
6098 | struct dentry *t_options; | |
a8259075 SR |
6099 | int i; |
6100 | ||
2b6080f2 | 6101 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
6102 | if (!t_options) |
6103 | return; | |
6104 | ||
5452af66 | 6105 | for (i = 0; trace_options[i]; i++) |
2b6080f2 | 6106 | create_trace_option_core_file(tr, trace_options[i], i); |
a8259075 SR |
6107 | } |
6108 | ||
499e5470 SR |
6109 | static ssize_t |
6110 | rb_simple_read(struct file *filp, char __user *ubuf, | |
6111 | size_t cnt, loff_t *ppos) | |
6112 | { | |
348f0fc2 | 6113 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
6114 | char buf[64]; |
6115 | int r; | |
6116 | ||
10246fa3 | 6117 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
6118 | r = sprintf(buf, "%d\n", r); |
6119 | ||
6120 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
6121 | } | |
6122 | ||
6123 | static ssize_t | |
6124 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
6125 | size_t cnt, loff_t *ppos) | |
6126 | { | |
348f0fc2 | 6127 | struct trace_array *tr = filp->private_data; |
12883efb | 6128 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
6129 | unsigned long val; |
6130 | int ret; | |
6131 | ||
6132 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
6133 | if (ret) | |
6134 | return ret; | |
6135 | ||
6136 | if (buffer) { | |
2df8f8a6 SR |
6137 | mutex_lock(&trace_types_lock); |
6138 | if (val) { | |
10246fa3 | 6139 | tracer_tracing_on(tr); |
2b6080f2 SR |
6140 | if (tr->current_trace->start) |
6141 | tr->current_trace->start(tr); | |
2df8f8a6 | 6142 | } else { |
10246fa3 | 6143 | tracer_tracing_off(tr); |
2b6080f2 SR |
6144 | if (tr->current_trace->stop) |
6145 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
6146 | } |
6147 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
6148 | } |
6149 | ||
6150 | (*ppos)++; | |
6151 | ||
6152 | return cnt; | |
6153 | } | |
6154 | ||
6155 | static const struct file_operations rb_simple_fops = { | |
7b85af63 | 6156 | .open = tracing_open_generic_tr, |
499e5470 SR |
6157 | .read = rb_simple_read, |
6158 | .write = rb_simple_write, | |
7b85af63 | 6159 | .release = tracing_release_generic_tr, |
499e5470 SR |
6160 | .llseek = default_llseek, |
6161 | }; | |
6162 | ||
277ba044 SR |
6163 | struct dentry *trace_instance_dir; |
6164 | ||
6165 | static void | |
6166 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer); | |
6167 | ||
55034cd6 SRRH |
6168 | static int |
6169 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
6170 | { |
6171 | enum ring_buffer_flags rb_flags; | |
737223fb SRRH |
6172 | |
6173 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; | |
6174 | ||
dced341b SRRH |
6175 | buf->tr = tr; |
6176 | ||
55034cd6 SRRH |
6177 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
6178 | if (!buf->buffer) | |
6179 | return -ENOMEM; | |
737223fb | 6180 | |
55034cd6 SRRH |
6181 | buf->data = alloc_percpu(struct trace_array_cpu); |
6182 | if (!buf->data) { | |
6183 | ring_buffer_free(buf->buffer); | |
6184 | return -ENOMEM; | |
6185 | } | |
737223fb | 6186 | |
737223fb SRRH |
6187 | /* Allocate the first page for all buffers */ |
6188 | set_buffer_entries(&tr->trace_buffer, | |
6189 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
6190 | ||
55034cd6 SRRH |
6191 | return 0; |
6192 | } | |
737223fb | 6193 | |
55034cd6 SRRH |
6194 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
6195 | { | |
6196 | int ret; | |
737223fb | 6197 | |
55034cd6 SRRH |
6198 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
6199 | if (ret) | |
6200 | return ret; | |
737223fb | 6201 | |
55034cd6 SRRH |
6202 | #ifdef CONFIG_TRACER_MAX_TRACE |
6203 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
6204 | allocate_snapshot ? size : 1); | |
6205 | if (WARN_ON(ret)) { | |
737223fb | 6206 | ring_buffer_free(tr->trace_buffer.buffer); |
55034cd6 SRRH |
6207 | free_percpu(tr->trace_buffer.data); |
6208 | return -ENOMEM; | |
6209 | } | |
6210 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 6211 | |
55034cd6 SRRH |
6212 | /* |
6213 | * Only the top level trace array gets its snapshot allocated | |
6214 | * from the kernel command line. | |
6215 | */ | |
6216 | allocate_snapshot = false; | |
737223fb | 6217 | #endif |
55034cd6 | 6218 | return 0; |
737223fb SRRH |
6219 | } |
6220 | ||
f0b70cc4 SRRH |
6221 | static void free_trace_buffer(struct trace_buffer *buf) |
6222 | { | |
6223 | if (buf->buffer) { | |
6224 | ring_buffer_free(buf->buffer); | |
6225 | buf->buffer = NULL; | |
6226 | free_percpu(buf->data); | |
6227 | buf->data = NULL; | |
6228 | } | |
6229 | } | |
6230 | ||
23aaa3c1 SRRH |
6231 | static void free_trace_buffers(struct trace_array *tr) |
6232 | { | |
6233 | if (!tr) | |
6234 | return; | |
6235 | ||
f0b70cc4 | 6236 | free_trace_buffer(&tr->trace_buffer); |
23aaa3c1 SRRH |
6237 | |
6238 | #ifdef CONFIG_TRACER_MAX_TRACE | |
f0b70cc4 | 6239 | free_trace_buffer(&tr->max_buffer); |
23aaa3c1 SRRH |
6240 | #endif |
6241 | } | |
6242 | ||
737223fb SRRH |
6243 | static int new_instance_create(const char *name) |
6244 | { | |
277ba044 SR |
6245 | struct trace_array *tr; |
6246 | int ret; | |
277ba044 SR |
6247 | |
6248 | mutex_lock(&trace_types_lock); | |
6249 | ||
6250 | ret = -EEXIST; | |
6251 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6252 | if (tr->name && strcmp(tr->name, name) == 0) | |
6253 | goto out_unlock; | |
6254 | } | |
6255 | ||
6256 | ret = -ENOMEM; | |
6257 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
6258 | if (!tr) | |
6259 | goto out_unlock; | |
6260 | ||
6261 | tr->name = kstrdup(name, GFP_KERNEL); | |
6262 | if (!tr->name) | |
6263 | goto out_free_tr; | |
6264 | ||
ccfe9e42 AL |
6265 | if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) |
6266 | goto out_free_tr; | |
6267 | ||
6268 | cpumask_copy(tr->tracing_cpumask, cpu_all_mask); | |
6269 | ||
277ba044 SR |
6270 | raw_spin_lock_init(&tr->start_lock); |
6271 | ||
0b9b12c1 SRRH |
6272 | tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
6273 | ||
277ba044 SR |
6274 | tr->current_trace = &nop_trace; |
6275 | ||
6276 | INIT_LIST_HEAD(&tr->systems); | |
6277 | INIT_LIST_HEAD(&tr->events); | |
6278 | ||
737223fb | 6279 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
6280 | goto out_free_tr; |
6281 | ||
277ba044 SR |
6282 | tr->dir = debugfs_create_dir(name, trace_instance_dir); |
6283 | if (!tr->dir) | |
6284 | goto out_free_tr; | |
6285 | ||
6286 | ret = event_trace_add_tracer(tr->dir, tr); | |
609e85a7 AL |
6287 | if (ret) { |
6288 | debugfs_remove_recursive(tr->dir); | |
277ba044 | 6289 | goto out_free_tr; |
609e85a7 | 6290 | } |
277ba044 SR |
6291 | |
6292 | init_tracer_debugfs(tr, tr->dir); | |
6293 | ||
6294 | list_add(&tr->list, &ftrace_trace_arrays); | |
6295 | ||
6296 | mutex_unlock(&trace_types_lock); | |
6297 | ||
6298 | return 0; | |
6299 | ||
6300 | out_free_tr: | |
23aaa3c1 | 6301 | free_trace_buffers(tr); |
ccfe9e42 | 6302 | free_cpumask_var(tr->tracing_cpumask); |
277ba044 SR |
6303 | kfree(tr->name); |
6304 | kfree(tr); | |
6305 | ||
6306 | out_unlock: | |
6307 | mutex_unlock(&trace_types_lock); | |
6308 | ||
6309 | return ret; | |
6310 | ||
6311 | } | |
6312 | ||
0c8916c3 SR |
6313 | static int instance_delete(const char *name) |
6314 | { | |
6315 | struct trace_array *tr; | |
6316 | int found = 0; | |
6317 | int ret; | |
6318 | ||
6319 | mutex_lock(&trace_types_lock); | |
6320 | ||
6321 | ret = -ENODEV; | |
6322 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6323 | if (tr->name && strcmp(tr->name, name) == 0) { | |
6324 | found = 1; | |
6325 | break; | |
6326 | } | |
6327 | } | |
6328 | if (!found) | |
6329 | goto out_unlock; | |
6330 | ||
a695cb58 SRRH |
6331 | ret = -EBUSY; |
6332 | if (tr->ref) | |
6333 | goto out_unlock; | |
6334 | ||
0c8916c3 SR |
6335 | list_del(&tr->list); |
6336 | ||
6b450d25 | 6337 | tracing_set_nop(tr); |
0c8916c3 | 6338 | event_trace_del_tracer(tr); |
591dffda | 6339 | ftrace_destroy_function_files(tr); |
0c8916c3 | 6340 | debugfs_remove_recursive(tr->dir); |
a9fcaaac | 6341 | free_trace_buffers(tr); |
0c8916c3 SR |
6342 | |
6343 | kfree(tr->name); | |
6344 | kfree(tr); | |
6345 | ||
6346 | ret = 0; | |
6347 | ||
6348 | out_unlock: | |
6349 | mutex_unlock(&trace_types_lock); | |
6350 | ||
6351 | return ret; | |
6352 | } | |
6353 | ||
277ba044 SR |
6354 | static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t mode) |
6355 | { | |
6356 | struct dentry *parent; | |
6357 | int ret; | |
6358 | ||
6359 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
6360 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
6361 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
6362 | return -ENOENT; | |
6363 | ||
6364 | /* | |
6365 | * The inode mutex is locked, but debugfs_create_dir() will also | |
6366 | * take the mutex. As the instances directory can not be destroyed | |
6367 | * or changed in any other way, it is safe to unlock it, and | |
6368 | * let the dentry try. If two users try to make the same dir at | |
6369 | * the same time, then the new_instance_create() will determine the | |
6370 | * winner. | |
6371 | */ | |
6372 | mutex_unlock(&inode->i_mutex); | |
6373 | ||
6374 | ret = new_instance_create(dentry->d_iname); | |
6375 | ||
6376 | mutex_lock(&inode->i_mutex); | |
6377 | ||
6378 | return ret; | |
6379 | } | |
6380 | ||
0c8916c3 SR |
6381 | static int instance_rmdir(struct inode *inode, struct dentry *dentry) |
6382 | { | |
6383 | struct dentry *parent; | |
6384 | int ret; | |
6385 | ||
6386 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
6387 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
6388 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
6389 | return -ENOENT; | |
6390 | ||
6391 | /* The caller did a dget() on dentry */ | |
6392 | mutex_unlock(&dentry->d_inode->i_mutex); | |
6393 | ||
6394 | /* | |
6395 | * The inode mutex is locked, but debugfs_create_dir() will also | |
6396 | * take the mutex. As the instances directory can not be destroyed | |
6397 | * or changed in any other way, it is safe to unlock it, and | |
6398 | * let the dentry try. If two users try to make the same dir at | |
6399 | * the same time, then the instance_delete() will determine the | |
6400 | * winner. | |
6401 | */ | |
6402 | mutex_unlock(&inode->i_mutex); | |
6403 | ||
6404 | ret = instance_delete(dentry->d_iname); | |
6405 | ||
6406 | mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); | |
6407 | mutex_lock(&dentry->d_inode->i_mutex); | |
6408 | ||
6409 | return ret; | |
6410 | } | |
6411 | ||
277ba044 SR |
6412 | static const struct inode_operations instance_dir_inode_operations = { |
6413 | .lookup = simple_lookup, | |
6414 | .mkdir = instance_mkdir, | |
0c8916c3 | 6415 | .rmdir = instance_rmdir, |
277ba044 SR |
6416 | }; |
6417 | ||
6418 | static __init void create_trace_instances(struct dentry *d_tracer) | |
6419 | { | |
6420 | trace_instance_dir = debugfs_create_dir("instances", d_tracer); | |
6421 | if (WARN_ON(!trace_instance_dir)) | |
6422 | return; | |
6423 | ||
6424 | /* Hijack the dir inode operations, to allow mkdir */ | |
6425 | trace_instance_dir->d_inode->i_op = &instance_dir_inode_operations; | |
6426 | } | |
6427 | ||
2b6080f2 SR |
6428 | static void |
6429 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) | |
6430 | { | |
121aaee7 | 6431 | int cpu; |
2b6080f2 | 6432 | |
607e2ea1 SRRH |
6433 | trace_create_file("available_tracers", 0444, d_tracer, |
6434 | tr, &show_traces_fops); | |
6435 | ||
6436 | trace_create_file("current_tracer", 0644, d_tracer, | |
6437 | tr, &set_tracer_fops); | |
6438 | ||
ccfe9e42 AL |
6439 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
6440 | tr, &tracing_cpumask_fops); | |
6441 | ||
2b6080f2 SR |
6442 | trace_create_file("trace_options", 0644, d_tracer, |
6443 | tr, &tracing_iter_fops); | |
6444 | ||
6445 | trace_create_file("trace", 0644, d_tracer, | |
6484c71c | 6446 | tr, &tracing_fops); |
2b6080f2 SR |
6447 | |
6448 | trace_create_file("trace_pipe", 0444, d_tracer, | |
15544209 | 6449 | tr, &tracing_pipe_fops); |
2b6080f2 SR |
6450 | |
6451 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
0bc392ee | 6452 | tr, &tracing_entries_fops); |
2b6080f2 SR |
6453 | |
6454 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
6455 | tr, &tracing_total_entries_fops); | |
6456 | ||
238ae93d | 6457 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
6458 | tr, &tracing_free_buffer_fops); |
6459 | ||
6460 | trace_create_file("trace_marker", 0220, d_tracer, | |
6461 | tr, &tracing_mark_fops); | |
6462 | ||
6463 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
6464 | &trace_clock_fops); | |
6465 | ||
6466 | trace_create_file("tracing_on", 0644, d_tracer, | |
6484c71c | 6467 | tr, &rb_simple_fops); |
ce9bae55 | 6468 | |
6d9b3fa5 SRRH |
6469 | #ifdef CONFIG_TRACER_MAX_TRACE |
6470 | trace_create_file("tracing_max_latency", 0644, d_tracer, | |
6471 | &tr->max_latency, &tracing_max_lat_fops); | |
6472 | #endif | |
6473 | ||
591dffda SRRH |
6474 | if (ftrace_create_function_files(tr, d_tracer)) |
6475 | WARN(1, "Could not allocate function filter files"); | |
6476 | ||
ce9bae55 SRRH |
6477 | #ifdef CONFIG_TRACER_SNAPSHOT |
6478 | trace_create_file("snapshot", 0644, d_tracer, | |
6484c71c | 6479 | tr, &snapshot_fops); |
ce9bae55 | 6480 | #endif |
121aaee7 SRRH |
6481 | |
6482 | for_each_tracing_cpu(cpu) | |
6483 | tracing_init_debugfs_percpu(tr, cpu); | |
6484 | ||
2b6080f2 SR |
6485 | } |
6486 | ||
b5ad384e | 6487 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
6488 | { |
6489 | struct dentry *d_tracer; | |
bc0c38d1 | 6490 | |
7e53bd42 LJ |
6491 | trace_access_lock_init(); |
6492 | ||
bc0c38d1 | 6493 | d_tracer = tracing_init_dentry(); |
ed6f1c99 NK |
6494 | if (!d_tracer) |
6495 | return 0; | |
bc0c38d1 | 6496 | |
2b6080f2 | 6497 | init_tracer_debugfs(&global_trace, d_tracer); |
bc0c38d1 | 6498 | |
5452af66 FW |
6499 | trace_create_file("tracing_thresh", 0644, d_tracer, |
6500 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 6501 | |
339ae5d3 | 6502 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
6503 | NULL, &tracing_readme_fops); |
6504 | ||
69abe6a5 AP |
6505 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
6506 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 6507 | |
939c7a4f YY |
6508 | trace_create_file("saved_cmdlines_size", 0644, d_tracer, |
6509 | NULL, &tracing_saved_cmdlines_size_fops); | |
6510 | ||
bc0c38d1 | 6511 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
6512 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
6513 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 6514 | #endif |
b04cc6b1 | 6515 | |
277ba044 | 6516 | create_trace_instances(d_tracer); |
5452af66 | 6517 | |
2b6080f2 | 6518 | create_trace_options_dir(&global_trace); |
b04cc6b1 | 6519 | |
b5ad384e | 6520 | return 0; |
bc0c38d1 SR |
6521 | } |
6522 | ||
3f5a54e3 SR |
6523 | static int trace_panic_handler(struct notifier_block *this, |
6524 | unsigned long event, void *unused) | |
6525 | { | |
944ac425 | 6526 | if (ftrace_dump_on_oops) |
cecbca96 | 6527 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6528 | return NOTIFY_OK; |
6529 | } | |
6530 | ||
6531 | static struct notifier_block trace_panic_notifier = { | |
6532 | .notifier_call = trace_panic_handler, | |
6533 | .next = NULL, | |
6534 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
6535 | }; | |
6536 | ||
6537 | static int trace_die_handler(struct notifier_block *self, | |
6538 | unsigned long val, | |
6539 | void *data) | |
6540 | { | |
6541 | switch (val) { | |
6542 | case DIE_OOPS: | |
944ac425 | 6543 | if (ftrace_dump_on_oops) |
cecbca96 | 6544 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6545 | break; |
6546 | default: | |
6547 | break; | |
6548 | } | |
6549 | return NOTIFY_OK; | |
6550 | } | |
6551 | ||
6552 | static struct notifier_block trace_die_notifier = { | |
6553 | .notifier_call = trace_die_handler, | |
6554 | .priority = 200 | |
6555 | }; | |
6556 | ||
6557 | /* | |
6558 | * printk is set to max of 1024, we really don't need it that big. | |
6559 | * Nothing should be printing 1000 characters anyway. | |
6560 | */ | |
6561 | #define TRACE_MAX_PRINT 1000 | |
6562 | ||
6563 | /* | |
6564 | * Define here KERN_TRACE so that we have one place to modify | |
6565 | * it if we decide to change what log level the ftrace dump | |
6566 | * should be at. | |
6567 | */ | |
428aee14 | 6568 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 6569 | |
955b61e5 | 6570 | void |
3f5a54e3 SR |
6571 | trace_printk_seq(struct trace_seq *s) |
6572 | { | |
6573 | /* Probably should print a warning here. */ | |
bd6df187 J |
6574 | if (s->len >= TRACE_MAX_PRINT) |
6575 | s->len = TRACE_MAX_PRINT; | |
3f5a54e3 SR |
6576 | |
6577 | /* should be zero ended, but we are paranoid. */ | |
6578 | s->buffer[s->len] = 0; | |
6579 | ||
6580 | printk(KERN_TRACE "%s", s->buffer); | |
6581 | ||
f9520750 | 6582 | trace_seq_init(s); |
3f5a54e3 SR |
6583 | } |
6584 | ||
955b61e5 JW |
6585 | void trace_init_global_iter(struct trace_iterator *iter) |
6586 | { | |
6587 | iter->tr = &global_trace; | |
2b6080f2 | 6588 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 6589 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 6590 | iter->trace_buffer = &global_trace.trace_buffer; |
b2f974d6 CS |
6591 | |
6592 | if (iter->trace && iter->trace->open) | |
6593 | iter->trace->open(iter); | |
6594 | ||
6595 | /* Annotate start of buffers if we had overruns */ | |
6596 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) | |
6597 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
6598 | ||
6599 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ | |
6600 | if (trace_clocks[iter->tr->clock_id].in_ns) | |
6601 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
955b61e5 JW |
6602 | } |
6603 | ||
7fe70b57 | 6604 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 6605 | { |
3f5a54e3 SR |
6606 | /* use static because iter can be a bit big for the stack */ |
6607 | static struct trace_iterator iter; | |
7fe70b57 | 6608 | static atomic_t dump_running; |
cf586b61 | 6609 | unsigned int old_userobj; |
d769041f SR |
6610 | unsigned long flags; |
6611 | int cnt = 0, cpu; | |
3f5a54e3 | 6612 | |
7fe70b57 SRRH |
6613 | /* Only allow one dump user at a time. */ |
6614 | if (atomic_inc_return(&dump_running) != 1) { | |
6615 | atomic_dec(&dump_running); | |
6616 | return; | |
6617 | } | |
3f5a54e3 | 6618 | |
7fe70b57 SRRH |
6619 | /* |
6620 | * Always turn off tracing when we dump. | |
6621 | * We don't need to show trace output of what happens | |
6622 | * between multiple crashes. | |
6623 | * | |
6624 | * If the user does a sysrq-z, then they can re-enable | |
6625 | * tracing with echo 1 > tracing_on. | |
6626 | */ | |
0ee6b6cf | 6627 | tracing_off(); |
cf586b61 | 6628 | |
7fe70b57 | 6629 | local_irq_save(flags); |
3f5a54e3 | 6630 | |
38dbe0b1 | 6631 | /* Simulate the iterator */ |
955b61e5 JW |
6632 | trace_init_global_iter(&iter); |
6633 | ||
d769041f | 6634 | for_each_tracing_cpu(cpu) { |
12883efb | 6635 | atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled); |
d769041f SR |
6636 | } |
6637 | ||
cf586b61 FW |
6638 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
6639 | ||
b54d3de9 TE |
6640 | /* don't look at user memory in panic mode */ |
6641 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
6642 | ||
cecbca96 FW |
6643 | switch (oops_dump_mode) { |
6644 | case DUMP_ALL: | |
ae3b5093 | 6645 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6646 | break; |
6647 | case DUMP_ORIG: | |
6648 | iter.cpu_file = raw_smp_processor_id(); | |
6649 | break; | |
6650 | case DUMP_NONE: | |
6651 | goto out_enable; | |
6652 | default: | |
6653 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 6654 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6655 | } |
6656 | ||
6657 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 6658 | |
7fe70b57 SRRH |
6659 | /* Did function tracer already get disabled? */ |
6660 | if (ftrace_is_dead()) { | |
6661 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
6662 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
6663 | } | |
6664 | ||
3f5a54e3 SR |
6665 | /* |
6666 | * We need to stop all tracing on all CPUS to read the | |
6667 | * the next buffer. This is a bit expensive, but is | |
6668 | * not done often. We fill all what we can read, | |
6669 | * and then release the locks again. | |
6670 | */ | |
6671 | ||
3f5a54e3 SR |
6672 | while (!trace_empty(&iter)) { |
6673 | ||
6674 | if (!cnt) | |
6675 | printk(KERN_TRACE "---------------------------------\n"); | |
6676 | ||
6677 | cnt++; | |
6678 | ||
6679 | /* reset all but tr, trace, and overruns */ | |
6680 | memset(&iter.seq, 0, | |
6681 | sizeof(struct trace_iterator) - | |
6682 | offsetof(struct trace_iterator, seq)); | |
6683 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
6684 | iter.pos = -1; | |
6685 | ||
955b61e5 | 6686 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
6687 | int ret; |
6688 | ||
6689 | ret = print_trace_line(&iter); | |
6690 | if (ret != TRACE_TYPE_NO_CONSUME) | |
6691 | trace_consume(&iter); | |
3f5a54e3 | 6692 | } |
b892e5c8 | 6693 | touch_nmi_watchdog(); |
3f5a54e3 SR |
6694 | |
6695 | trace_printk_seq(&iter.seq); | |
6696 | } | |
6697 | ||
6698 | if (!cnt) | |
6699 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
6700 | else | |
6701 | printk(KERN_TRACE "---------------------------------\n"); | |
6702 | ||
cecbca96 | 6703 | out_enable: |
7fe70b57 | 6704 | trace_flags |= old_userobj; |
cf586b61 | 6705 | |
7fe70b57 SRRH |
6706 | for_each_tracing_cpu(cpu) { |
6707 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); | |
cf586b61 | 6708 | } |
7fe70b57 | 6709 | atomic_dec(&dump_running); |
cd891ae0 | 6710 | local_irq_restore(flags); |
3f5a54e3 | 6711 | } |
a8eecf22 | 6712 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 6713 | |
3928a8a2 | 6714 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 6715 | { |
73c5162a | 6716 | int ring_buf_size; |
9e01c1b7 | 6717 | int ret = -ENOMEM; |
4c11d7ae | 6718 | |
750912fa | 6719 | |
9e01c1b7 RR |
6720 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
6721 | goto out; | |
6722 | ||
ccfe9e42 | 6723 | if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) |
9e01c1b7 | 6724 | goto out_free_buffer_mask; |
4c11d7ae | 6725 | |
07d777fe SR |
6726 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
6727 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 6728 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
6729 | trace_printk_init_buffers(); |
6730 | ||
73c5162a SR |
6731 | /* To save memory, keep the ring buffer size to its minimum */ |
6732 | if (ring_buffer_expanded) | |
6733 | ring_buf_size = trace_buf_size; | |
6734 | else | |
6735 | ring_buf_size = 1; | |
6736 | ||
9e01c1b7 | 6737 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
ccfe9e42 | 6738 | cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); |
9e01c1b7 | 6739 | |
2b6080f2 SR |
6740 | raw_spin_lock_init(&global_trace.start_lock); |
6741 | ||
2c4a33ab SRRH |
6742 | /* Used for event triggers */ |
6743 | temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); | |
6744 | if (!temp_buffer) | |
6745 | goto out_free_cpumask; | |
6746 | ||
939c7a4f YY |
6747 | if (trace_create_savedcmd() < 0) |
6748 | goto out_free_temp_buffer; | |
6749 | ||
9e01c1b7 | 6750 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 6751 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
6752 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
6753 | WARN_ON(1); | |
939c7a4f | 6754 | goto out_free_savedcmd; |
4c11d7ae | 6755 | } |
a7603ff4 | 6756 | |
499e5470 SR |
6757 | if (global_trace.buffer_disabled) |
6758 | tracing_off(); | |
4c11d7ae | 6759 | |
e1e232ca SR |
6760 | if (trace_boot_clock) { |
6761 | ret = tracing_set_clock(&global_trace, trace_boot_clock); | |
6762 | if (ret < 0) | |
6763 | pr_warning("Trace clock %s not defined, going back to default\n", | |
6764 | trace_boot_clock); | |
6765 | } | |
6766 | ||
ca164318 SRRH |
6767 | /* |
6768 | * register_tracer() might reference current_trace, so it | |
6769 | * needs to be set before we register anything. This is | |
6770 | * just a bootstrap of current_trace anyway. | |
6771 | */ | |
2b6080f2 SR |
6772 | global_trace.current_trace = &nop_trace; |
6773 | ||
0b9b12c1 SRRH |
6774 | global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
6775 | ||
4104d326 SRRH |
6776 | ftrace_init_global_array_ops(&global_trace); |
6777 | ||
ca164318 SRRH |
6778 | register_tracer(&nop_trace); |
6779 | ||
60a11774 SR |
6780 | /* All seems OK, enable tracing */ |
6781 | tracing_disabled = 0; | |
3928a8a2 | 6782 | |
3f5a54e3 SR |
6783 | atomic_notifier_chain_register(&panic_notifier_list, |
6784 | &trace_panic_notifier); | |
6785 | ||
6786 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 6787 | |
ae63b31e SR |
6788 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
6789 | ||
6790 | INIT_LIST_HEAD(&global_trace.systems); | |
6791 | INIT_LIST_HEAD(&global_trace.events); | |
6792 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
6793 | ||
7bcfaf54 SR |
6794 | while (trace_boot_options) { |
6795 | char *option; | |
6796 | ||
6797 | option = strsep(&trace_boot_options, ","); | |
2b6080f2 | 6798 | trace_set_options(&global_trace, option); |
7bcfaf54 SR |
6799 | } |
6800 | ||
77fd5c15 SRRH |
6801 | register_snapshot_cmd(); |
6802 | ||
2fc1dfbe | 6803 | return 0; |
3f5a54e3 | 6804 | |
939c7a4f YY |
6805 | out_free_savedcmd: |
6806 | free_saved_cmdlines_buffer(savedcmd); | |
2c4a33ab SRRH |
6807 | out_free_temp_buffer: |
6808 | ring_buffer_free(temp_buffer); | |
9e01c1b7 | 6809 | out_free_cpumask: |
ccfe9e42 | 6810 | free_cpumask_var(global_trace.tracing_cpumask); |
9e01c1b7 RR |
6811 | out_free_buffer_mask: |
6812 | free_cpumask_var(tracing_buffer_mask); | |
6813 | out: | |
6814 | return ret; | |
bc0c38d1 | 6815 | } |
b2821ae6 SR |
6816 | |
6817 | __init static int clear_boot_tracer(void) | |
6818 | { | |
6819 | /* | |
6820 | * The default tracer at boot buffer is an init section. | |
6821 | * This function is called in lateinit. If we did not | |
6822 | * find the boot tracer, then clear it out, to prevent | |
6823 | * later registration from accessing the buffer that is | |
6824 | * about to be freed. | |
6825 | */ | |
6826 | if (!default_bootup_tracer) | |
6827 | return 0; | |
6828 | ||
6829 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
6830 | default_bootup_tracer); | |
6831 | default_bootup_tracer = NULL; | |
6832 | ||
6833 | return 0; | |
6834 | } | |
6835 | ||
b5ad384e FW |
6836 | early_initcall(tracer_alloc_buffers); |
6837 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 6838 | late_initcall(clear_boot_tracer); |