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Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
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 | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
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> | |
405f5571 | 20 | #include <linux/smp_lock.h> |
3f5a54e3 | 21 | #include <linux/notifier.h> |
2cadf913 | 22 | #include <linux/irqflags.h> |
bc0c38d1 | 23 | #include <linux/debugfs.h> |
4c11d7ae | 24 | #include <linux/pagemap.h> |
bc0c38d1 SR |
25 | #include <linux/hardirq.h> |
26 | #include <linux/linkage.h> | |
27 | #include <linux/uaccess.h> | |
2cadf913 | 28 | #include <linux/kprobes.h> |
bc0c38d1 SR |
29 | #include <linux/ftrace.h> |
30 | #include <linux/module.h> | |
31 | #include <linux/percpu.h> | |
2cadf913 | 32 | #include <linux/splice.h> |
3f5a54e3 | 33 | #include <linux/kdebug.h> |
5f0c6c03 | 34 | #include <linux/string.h> |
7e53bd42 | 35 | #include <linux/rwsem.h> |
bc0c38d1 SR |
36 | #include <linux/ctype.h> |
37 | #include <linux/init.h> | |
2a2cc8f7 | 38 | #include <linux/poll.h> |
bc0c38d1 SR |
39 | #include <linux/gfp.h> |
40 | #include <linux/fs.h> | |
86387f7e | 41 | |
bc0c38d1 | 42 | #include "trace.h" |
f0868d1e | 43 | #include "trace_output.h" |
bc0c38d1 | 44 | |
3928a8a2 SR |
45 | #define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE) |
46 | ||
73c5162a SR |
47 | /* |
48 | * On boot up, the ring buffer is set to the minimum size, so that | |
49 | * we do not waste memory on systems that are not using tracing. | |
50 | */ | |
020e5f85 | 51 | int ring_buffer_expanded; |
73c5162a | 52 | |
8e1b82e0 FW |
53 | /* |
54 | * We need to change this state when a selftest is running. | |
ff32504f FW |
55 | * A selftest will lurk into the ring-buffer to count the |
56 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 57 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
58 | * at the same time, giving false positive or negative results. |
59 | */ | |
8e1b82e0 | 60 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 61 | |
b2821ae6 SR |
62 | /* |
63 | * If a tracer is running, we do not want to run SELFTEST. | |
64 | */ | |
020e5f85 | 65 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 66 | |
adf9f195 FW |
67 | /* For tracers that don't implement custom flags */ |
68 | static struct tracer_opt dummy_tracer_opt[] = { | |
69 | { } | |
70 | }; | |
71 | ||
72 | static struct tracer_flags dummy_tracer_flags = { | |
73 | .val = 0, | |
74 | .opts = dummy_tracer_opt | |
75 | }; | |
76 | ||
77 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
78 | { | |
79 | return 0; | |
80 | } | |
0f048701 SR |
81 | |
82 | /* | |
83 | * Kill all tracing for good (never come back). | |
84 | * It is initialized to 1 but will turn to zero if the initialization | |
85 | * of the tracer is successful. But that is the only place that sets | |
86 | * this back to zero. | |
87 | */ | |
4fd27358 | 88 | static int tracing_disabled = 1; |
0f048701 | 89 | |
9288f99a | 90 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f SR |
91 | |
92 | static inline void ftrace_disable_cpu(void) | |
93 | { | |
94 | preempt_disable(); | |
dd17c8f7 | 95 | __this_cpu_inc(ftrace_cpu_disabled); |
d769041f SR |
96 | } |
97 | ||
98 | static inline void ftrace_enable_cpu(void) | |
99 | { | |
dd17c8f7 | 100 | __this_cpu_dec(ftrace_cpu_disabled); |
d769041f SR |
101 | preempt_enable(); |
102 | } | |
103 | ||
9e01c1b7 | 104 | static cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c SR |
105 | |
106 | #define for_each_tracing_cpu(cpu) \ | |
9e01c1b7 | 107 | for_each_cpu(cpu, tracing_buffer_mask) |
ab46428c | 108 | |
944ac425 SR |
109 | /* |
110 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
111 | * | |
112 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
113 | * is set, then ftrace_dump is called. This will output the contents | |
114 | * of the ftrace buffers to the console. This is very useful for | |
115 | * capturing traces that lead to crashes and outputing it to a | |
116 | * serial console. | |
117 | * | |
118 | * It is default off, but you can enable it with either specifying | |
119 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
120 | * /proc/sys/kernel/ftrace_dump_on_oops to true. | |
121 | */ | |
122 | int ftrace_dump_on_oops; | |
123 | ||
b2821ae6 SR |
124 | static int tracing_set_tracer(const char *buf); |
125 | ||
ee6c2c1b LZ |
126 | #define MAX_TRACER_SIZE 100 |
127 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 128 | static char *default_bootup_tracer; |
d9e54076 | 129 | |
1beee96b | 130 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 131 | { |
ee6c2c1b | 132 | strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 133 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a SR |
134 | /* We are using ftrace early, expand it */ |
135 | ring_buffer_expanded = 1; | |
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 | { | |
142 | ftrace_dump_on_oops = 1; | |
143 | return 1; | |
144 | } | |
145 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 146 | |
cf8e3474 | 147 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
148 | { |
149 | nsec += 500; | |
150 | do_div(nsec, 1000); | |
151 | return nsec; | |
152 | } | |
153 | ||
4fcdae83 SR |
154 | /* |
155 | * The global_trace is the descriptor that holds the tracing | |
156 | * buffers for the live tracing. For each CPU, it contains | |
157 | * a link list of pages that will store trace entries. The | |
158 | * page descriptor of the pages in the memory is used to hold | |
159 | * the link list by linking the lru item in the page descriptor | |
160 | * to each of the pages in the buffer per CPU. | |
161 | * | |
162 | * For each active CPU there is a data field that holds the | |
163 | * pages for the buffer for that CPU. Each CPU has the same number | |
164 | * of pages allocated for its buffer. | |
165 | */ | |
bc0c38d1 SR |
166 | static struct trace_array global_trace; |
167 | ||
168 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
169 | ||
e77405ad SR |
170 | int filter_current_check_discard(struct ring_buffer *buffer, |
171 | struct ftrace_event_call *call, void *rec, | |
eb02ce01 TZ |
172 | struct ring_buffer_event *event) |
173 | { | |
e77405ad | 174 | return filter_check_discard(call, rec, buffer, event); |
eb02ce01 | 175 | } |
17c873ec | 176 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 177 | |
37886f6a SR |
178 | cycle_t ftrace_now(int cpu) |
179 | { | |
180 | u64 ts; | |
181 | ||
182 | /* Early boot up does not have a buffer yet */ | |
183 | if (!global_trace.buffer) | |
184 | return trace_clock_local(); | |
185 | ||
186 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
187 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
188 | ||
189 | return ts; | |
190 | } | |
bc0c38d1 | 191 | |
4fcdae83 SR |
192 | /* |
193 | * The max_tr is used to snapshot the global_trace when a maximum | |
194 | * latency is reached. Some tracers will use this to store a maximum | |
195 | * trace while it continues examining live traces. | |
196 | * | |
197 | * The buffers for the max_tr are set up the same as the global_trace. | |
198 | * When a snapshot is taken, the link list of the max_tr is swapped | |
199 | * with the link list of the global_trace and the buffers are reset for | |
200 | * the global_trace so the tracing can continue. | |
201 | */ | |
bc0c38d1 SR |
202 | static struct trace_array max_tr; |
203 | ||
9705f69e | 204 | static DEFINE_PER_CPU(struct trace_array_cpu, max_tr_data); |
bc0c38d1 | 205 | |
4fcdae83 | 206 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 207 | static int tracer_enabled = 1; |
4fcdae83 | 208 | |
9036990d SR |
209 | /** |
210 | * tracing_is_enabled - return tracer_enabled status | |
211 | * | |
212 | * This function is used by other tracers to know the status | |
213 | * of the tracer_enabled flag. Tracers may use this function | |
214 | * to know if it should enable their features when starting | |
215 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
216 | */ | |
217 | int tracing_is_enabled(void) | |
218 | { | |
219 | return tracer_enabled; | |
220 | } | |
221 | ||
4fcdae83 | 222 | /* |
3928a8a2 SR |
223 | * trace_buf_size is the size in bytes that is allocated |
224 | * for a buffer. Note, the number of bytes is always rounded | |
225 | * to page size. | |
3f5a54e3 SR |
226 | * |
227 | * This number is purposely set to a low number of 16384. | |
228 | * If the dump on oops happens, it will be much appreciated | |
229 | * to not have to wait for all that output. Anyway this can be | |
230 | * boot time and run time configurable. | |
4fcdae83 | 231 | */ |
3928a8a2 | 232 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 233 | |
3928a8a2 | 234 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 235 | |
4fcdae83 | 236 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 237 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
238 | |
239 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 240 | static struct tracer *current_trace __read_mostly; |
4fcdae83 | 241 | |
4fcdae83 SR |
242 | /* |
243 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 244 | */ |
bc0c38d1 | 245 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 246 | |
7e53bd42 LJ |
247 | /* |
248 | * serialize the access of the ring buffer | |
249 | * | |
250 | * ring buffer serializes readers, but it is low level protection. | |
251 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
252 | * are not protected by ring buffer. | |
253 | * | |
254 | * The content of events may become garbage if we allow other process consumes | |
255 | * these events concurrently: | |
256 | * A) the page of the consumed events may become a normal page | |
257 | * (not reader page) in ring buffer, and this page will be rewrited | |
258 | * by events producer. | |
259 | * B) The page of the consumed events may become a page for splice_read, | |
260 | * and this page will be returned to system. | |
261 | * | |
262 | * These primitives allow multi process access to different cpu ring buffer | |
263 | * concurrently. | |
264 | * | |
265 | * These primitives don't distinguish read-only and read-consume access. | |
266 | * Multi read-only access are also serialized. | |
267 | */ | |
268 | ||
269 | #ifdef CONFIG_SMP | |
270 | static DECLARE_RWSEM(all_cpu_access_lock); | |
271 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
272 | ||
273 | static inline void trace_access_lock(int cpu) | |
274 | { | |
275 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
276 | /* gain it for accessing the whole ring buffer. */ | |
277 | down_write(&all_cpu_access_lock); | |
278 | } else { | |
279 | /* gain it for accessing a cpu ring buffer. */ | |
280 | ||
281 | /* Firstly block other trace_access_lock(TRACE_PIPE_ALL_CPU). */ | |
282 | down_read(&all_cpu_access_lock); | |
283 | ||
284 | /* Secondly block other access to this @cpu ring buffer. */ | |
285 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
286 | } | |
287 | } | |
288 | ||
289 | static inline void trace_access_unlock(int cpu) | |
290 | { | |
291 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
292 | up_write(&all_cpu_access_lock); | |
293 | } else { | |
294 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
295 | up_read(&all_cpu_access_lock); | |
296 | } | |
297 | } | |
298 | ||
299 | static inline void trace_access_lock_init(void) | |
300 | { | |
301 | int cpu; | |
302 | ||
303 | for_each_possible_cpu(cpu) | |
304 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
305 | } | |
306 | ||
307 | #else | |
308 | ||
309 | static DEFINE_MUTEX(access_lock); | |
310 | ||
311 | static inline void trace_access_lock(int cpu) | |
312 | { | |
313 | (void)cpu; | |
314 | mutex_lock(&access_lock); | |
315 | } | |
316 | ||
317 | static inline void trace_access_unlock(int cpu) | |
318 | { | |
319 | (void)cpu; | |
320 | mutex_unlock(&access_lock); | |
321 | } | |
322 | ||
323 | static inline void trace_access_lock_init(void) | |
324 | { | |
325 | } | |
326 | ||
327 | #endif | |
328 | ||
4fcdae83 | 329 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ |
4e655519 IM |
330 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
331 | ||
ee6bce52 | 332 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 333 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a SR |
334 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
335 | TRACE_ITER_GRAPH_TIME; | |
4e655519 | 336 | |
b8de7bd1 SR |
337 | static int trace_stop_count; |
338 | static DEFINE_SPINLOCK(tracing_start_lock); | |
339 | ||
4fcdae83 SR |
340 | /** |
341 | * trace_wake_up - wake up tasks waiting for trace input | |
342 | * | |
343 | * Simply wakes up any task that is blocked on the trace_wait | |
344 | * queue. These is used with trace_poll for tasks polling the trace. | |
345 | */ | |
4e655519 IM |
346 | void trace_wake_up(void) |
347 | { | |
89f19f04 AM |
348 | int cpu; |
349 | ||
350 | if (trace_flags & TRACE_ITER_BLOCK) | |
351 | return; | |
017730c1 IM |
352 | /* |
353 | * The runqueue_is_locked() can fail, but this is the best we | |
354 | * have for now: | |
355 | */ | |
89f19f04 AM |
356 | cpu = get_cpu(); |
357 | if (!runqueue_is_locked(cpu)) | |
4e655519 | 358 | wake_up(&trace_wait); |
89f19f04 | 359 | put_cpu(); |
4e655519 | 360 | } |
bc0c38d1 | 361 | |
3928a8a2 | 362 | static int __init set_buf_size(char *str) |
bc0c38d1 | 363 | { |
3928a8a2 | 364 | unsigned long buf_size; |
c6caeeb1 | 365 | |
bc0c38d1 SR |
366 | if (!str) |
367 | return 0; | |
9d612bef | 368 | buf_size = memparse(str, &str); |
c6caeeb1 | 369 | /* nr_entries can not be zero */ |
9d612bef | 370 | if (buf_size == 0) |
c6caeeb1 | 371 | return 0; |
3928a8a2 | 372 | trace_buf_size = buf_size; |
bc0c38d1 SR |
373 | return 1; |
374 | } | |
3928a8a2 | 375 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 376 | |
57f50be1 SR |
377 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
378 | { | |
379 | return nsecs / 1000; | |
380 | } | |
381 | ||
4fcdae83 | 382 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
383 | static const char *trace_options[] = { |
384 | "print-parent", | |
385 | "sym-offset", | |
386 | "sym-addr", | |
387 | "verbose", | |
f9896bf3 | 388 | "raw", |
5e3ca0ec | 389 | "hex", |
cb0f12aa | 390 | "bin", |
2a2cc8f7 | 391 | "block", |
86387f7e | 392 | "stacktrace", |
5e1607a0 | 393 | "trace_printk", |
b2a866f9 | 394 | "ftrace_preempt", |
9f029e83 | 395 | "branch", |
12ef7d44 | 396 | "annotate", |
02b67518 | 397 | "userstacktrace", |
b54d3de9 | 398 | "sym-userobj", |
66896a85 | 399 | "printk-msg-only", |
c4a8e8be | 400 | "context-info", |
c032ef64 | 401 | "latency-format", |
be6f164a | 402 | "sleep-time", |
a2a16d6a | 403 | "graph-time", |
bc0c38d1 SR |
404 | NULL |
405 | }; | |
406 | ||
5079f326 Z |
407 | static struct { |
408 | u64 (*func)(void); | |
409 | const char *name; | |
410 | } trace_clocks[] = { | |
411 | { trace_clock_local, "local" }, | |
412 | { trace_clock_global, "global" }, | |
413 | }; | |
414 | ||
415 | int trace_clock_id; | |
416 | ||
b63f39ea | 417 | /* |
418 | * trace_parser_get_init - gets the buffer for trace parser | |
419 | */ | |
420 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
421 | { | |
422 | memset(parser, 0, sizeof(*parser)); | |
423 | ||
424 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
425 | if (!parser->buffer) | |
426 | return 1; | |
427 | ||
428 | parser->size = size; | |
429 | return 0; | |
430 | } | |
431 | ||
432 | /* | |
433 | * trace_parser_put - frees the buffer for trace parser | |
434 | */ | |
435 | void trace_parser_put(struct trace_parser *parser) | |
436 | { | |
437 | kfree(parser->buffer); | |
438 | } | |
439 | ||
440 | /* | |
441 | * trace_get_user - reads the user input string separated by space | |
442 | * (matched by isspace(ch)) | |
443 | * | |
444 | * For each string found the 'struct trace_parser' is updated, | |
445 | * and the function returns. | |
446 | * | |
447 | * Returns number of bytes read. | |
448 | * | |
449 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
450 | */ | |
451 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
452 | size_t cnt, loff_t *ppos) | |
453 | { | |
454 | char ch; | |
455 | size_t read = 0; | |
456 | ssize_t ret; | |
457 | ||
458 | if (!*ppos) | |
459 | trace_parser_clear(parser); | |
460 | ||
461 | ret = get_user(ch, ubuf++); | |
462 | if (ret) | |
463 | goto out; | |
464 | ||
465 | read++; | |
466 | cnt--; | |
467 | ||
468 | /* | |
469 | * The parser is not finished with the last write, | |
470 | * continue reading the user input without skipping spaces. | |
471 | */ | |
472 | if (!parser->cont) { | |
473 | /* skip white space */ | |
474 | while (cnt && isspace(ch)) { | |
475 | ret = get_user(ch, ubuf++); | |
476 | if (ret) | |
477 | goto out; | |
478 | read++; | |
479 | cnt--; | |
480 | } | |
481 | ||
482 | /* only spaces were written */ | |
483 | if (isspace(ch)) { | |
484 | *ppos += read; | |
485 | ret = read; | |
486 | goto out; | |
487 | } | |
488 | ||
489 | parser->idx = 0; | |
490 | } | |
491 | ||
492 | /* read the non-space input */ | |
493 | while (cnt && !isspace(ch)) { | |
3c235a33 | 494 | if (parser->idx < parser->size - 1) |
b63f39ea | 495 | parser->buffer[parser->idx++] = ch; |
496 | else { | |
497 | ret = -EINVAL; | |
498 | goto out; | |
499 | } | |
500 | ret = get_user(ch, ubuf++); | |
501 | if (ret) | |
502 | goto out; | |
503 | read++; | |
504 | cnt--; | |
505 | } | |
506 | ||
507 | /* We either got finished input or we have to wait for another call. */ | |
508 | if (isspace(ch)) { | |
509 | parser->buffer[parser->idx] = 0; | |
510 | parser->cont = false; | |
511 | } else { | |
512 | parser->cont = true; | |
513 | parser->buffer[parser->idx++] = ch; | |
514 | } | |
515 | ||
516 | *ppos += read; | |
517 | ret = read; | |
518 | ||
519 | out: | |
520 | return ret; | |
521 | } | |
522 | ||
6c6c2796 PP |
523 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
524 | { | |
525 | int len; | |
526 | int ret; | |
527 | ||
2dc5d12b SR |
528 | if (!cnt) |
529 | return 0; | |
530 | ||
6c6c2796 PP |
531 | if (s->len <= s->readpos) |
532 | return -EBUSY; | |
533 | ||
534 | len = s->len - s->readpos; | |
535 | if (cnt > len) | |
536 | cnt = len; | |
537 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 538 | if (ret == cnt) |
6c6c2796 PP |
539 | return -EFAULT; |
540 | ||
2dc5d12b SR |
541 | cnt -= ret; |
542 | ||
e74da523 | 543 | s->readpos += cnt; |
6c6c2796 | 544 | return cnt; |
214023c3 SR |
545 | } |
546 | ||
b8b94265 | 547 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
548 | { |
549 | int len; | |
550 | void *ret; | |
551 | ||
552 | if (s->len <= s->readpos) | |
553 | return -EBUSY; | |
554 | ||
555 | len = s->len - s->readpos; | |
556 | if (cnt > len) | |
557 | cnt = len; | |
558 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
559 | if (!ret) | |
560 | return -EFAULT; | |
561 | ||
e74da523 | 562 | s->readpos += cnt; |
3c56819b EGM |
563 | return cnt; |
564 | } | |
565 | ||
5d4a9dba SR |
566 | /* |
567 | * ftrace_max_lock is used to protect the swapping of buffers | |
568 | * when taking a max snapshot. The buffers themselves are | |
569 | * protected by per_cpu spinlocks. But the action of the swap | |
570 | * needs its own lock. | |
571 | * | |
445c8951 | 572 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
573 | * with performance when lockdep debugging is enabled. |
574 | * | |
575 | * It is also used in other places outside the update_max_tr | |
576 | * so it needs to be defined outside of the | |
577 | * CONFIG_TRACER_MAX_TRACE. | |
578 | */ | |
445c8951 | 579 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 580 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba SR |
581 | |
582 | #ifdef CONFIG_TRACER_MAX_TRACE | |
583 | unsigned long __read_mostly tracing_max_latency; | |
584 | unsigned long __read_mostly tracing_thresh; | |
585 | ||
586 | /* | |
587 | * Copy the new maximum trace into the separate maximum-trace | |
588 | * structure. (this way the maximum trace is permanently saved, | |
589 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
590 | */ | |
591 | static void | |
592 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
593 | { | |
594 | struct trace_array_cpu *data = tr->data[cpu]; | |
8248ac05 | 595 | struct trace_array_cpu *max_data = tr->data[cpu]; |
5d4a9dba SR |
596 | |
597 | max_tr.cpu = cpu; | |
598 | max_tr.time_start = data->preempt_timestamp; | |
599 | ||
8248ac05 SR |
600 | max_data = max_tr.data[cpu]; |
601 | max_data->saved_latency = tracing_max_latency; | |
602 | max_data->critical_start = data->critical_start; | |
603 | max_data->critical_end = data->critical_end; | |
5d4a9dba SR |
604 | |
605 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
8248ac05 SR |
606 | max_data->pid = tsk->pid; |
607 | max_data->uid = task_uid(tsk); | |
608 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
609 | max_data->policy = tsk->policy; | |
610 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
611 | |
612 | /* record this tasks comm */ | |
613 | tracing_record_cmdline(tsk); | |
614 | } | |
615 | ||
4fcdae83 SR |
616 | /** |
617 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
618 | * @tr: tracer | |
619 | * @tsk: the task with the latency | |
620 | * @cpu: The cpu that initiated the trace. | |
621 | * | |
622 | * Flip the buffers between the @tr and the max_tr and record information | |
623 | * about which task was the cause of this latency. | |
624 | */ | |
e309b41d | 625 | void |
bc0c38d1 SR |
626 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
627 | { | |
3928a8a2 | 628 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 629 | |
b8de7bd1 SR |
630 | if (trace_stop_count) |
631 | return; | |
632 | ||
4c11d7ae | 633 | WARN_ON_ONCE(!irqs_disabled()); |
0199c4e6 | 634 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
635 | |
636 | tr->buffer = max_tr.buffer; | |
637 | max_tr.buffer = buf; | |
638 | ||
bc0c38d1 | 639 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 640 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
641 | } |
642 | ||
643 | /** | |
644 | * update_max_tr_single - only copy one trace over, and reset the rest | |
645 | * @tr - tracer | |
646 | * @tsk - task with the latency | |
647 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
648 | * |
649 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 650 | */ |
e309b41d | 651 | void |
bc0c38d1 SR |
652 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
653 | { | |
3928a8a2 | 654 | int ret; |
bc0c38d1 | 655 | |
b8de7bd1 SR |
656 | if (trace_stop_count) |
657 | return; | |
658 | ||
4c11d7ae | 659 | WARN_ON_ONCE(!irqs_disabled()); |
0199c4e6 | 660 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 661 | |
d769041f SR |
662 | ftrace_disable_cpu(); |
663 | ||
3928a8a2 SR |
664 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); |
665 | ||
e8165dbb SR |
666 | if (ret == -EBUSY) { |
667 | /* | |
668 | * We failed to swap the buffer due to a commit taking | |
669 | * place on this CPU. We fail to record, but we reset | |
670 | * the max trace buffer (no one writes directly to it) | |
671 | * and flag that it failed. | |
672 | */ | |
673 | trace_array_printk(&max_tr, _THIS_IP_, | |
674 | "Failed to swap buffers due to commit in progress\n"); | |
675 | } | |
676 | ||
d769041f SR |
677 | ftrace_enable_cpu(); |
678 | ||
e8165dbb | 679 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
680 | |
681 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 682 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 683 | } |
5d4a9dba | 684 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 685 | |
4fcdae83 SR |
686 | /** |
687 | * register_tracer - register a tracer with the ftrace system. | |
688 | * @type - the plugin for the tracer | |
689 | * | |
690 | * Register a new plugin tracer. | |
691 | */ | |
bc0c38d1 | 692 | int register_tracer(struct tracer *type) |
e7669b8e HE |
693 | __releases(kernel_lock) |
694 | __acquires(kernel_lock) | |
bc0c38d1 SR |
695 | { |
696 | struct tracer *t; | |
bc0c38d1 SR |
697 | int ret = 0; |
698 | ||
699 | if (!type->name) { | |
700 | pr_info("Tracer must have a name\n"); | |
701 | return -1; | |
702 | } | |
703 | ||
ee6c2c1b LZ |
704 | if (strlen(type->name) > MAX_TRACER_SIZE) { |
705 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); | |
706 | return -1; | |
707 | } | |
708 | ||
86fa2f60 IM |
709 | /* |
710 | * When this gets called we hold the BKL which means that | |
711 | * preemption is disabled. Various trace selftests however | |
712 | * need to disable and enable preemption for successful tests. | |
713 | * So we drop the BKL here and grab it after the tests again. | |
714 | */ | |
715 | unlock_kernel(); | |
bc0c38d1 | 716 | mutex_lock(&trace_types_lock); |
86fa2f60 | 717 | |
8e1b82e0 FW |
718 | tracing_selftest_running = true; |
719 | ||
bc0c38d1 SR |
720 | for (t = trace_types; t; t = t->next) { |
721 | if (strcmp(type->name, t->name) == 0) { | |
722 | /* already found */ | |
ee6c2c1b | 723 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
724 | type->name); |
725 | ret = -1; | |
726 | goto out; | |
727 | } | |
728 | } | |
729 | ||
adf9f195 FW |
730 | if (!type->set_flag) |
731 | type->set_flag = &dummy_set_flag; | |
732 | if (!type->flags) | |
733 | type->flags = &dummy_tracer_flags; | |
734 | else | |
735 | if (!type->flags->opts) | |
736 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
737 | if (!type->wait_pipe) |
738 | type->wait_pipe = default_wait_pipe; | |
739 | ||
adf9f195 | 740 | |
60a11774 | 741 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 742 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 743 | struct tracer *saved_tracer = current_trace; |
60a11774 | 744 | struct trace_array *tr = &global_trace; |
ff32504f | 745 | |
60a11774 SR |
746 | /* |
747 | * Run a selftest on this tracer. | |
748 | * Here we reset the trace buffer, and set the current | |
749 | * tracer to be this tracer. The tracer can then run some | |
750 | * internal tracing to verify that everything is in order. | |
751 | * If we fail, we do not register this tracer. | |
752 | */ | |
76f0d073 | 753 | tracing_reset_online_cpus(tr); |
86fa2f60 | 754 | |
60a11774 | 755 | current_trace = type; |
60a11774 SR |
756 | /* the test is responsible for initializing and enabling */ |
757 | pr_info("Testing tracer %s: ", type->name); | |
758 | ret = type->selftest(type, tr); | |
759 | /* the test is responsible for resetting too */ | |
760 | current_trace = saved_tracer; | |
60a11774 SR |
761 | if (ret) { |
762 | printk(KERN_CONT "FAILED!\n"); | |
763 | goto out; | |
764 | } | |
1d4db00a | 765 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 766 | tracing_reset_online_cpus(tr); |
86fa2f60 | 767 | |
60a11774 SR |
768 | printk(KERN_CONT "PASSED\n"); |
769 | } | |
770 | #endif | |
771 | ||
bc0c38d1 SR |
772 | type->next = trace_types; |
773 | trace_types = type; | |
60a11774 | 774 | |
bc0c38d1 | 775 | out: |
8e1b82e0 | 776 | tracing_selftest_running = false; |
bc0c38d1 SR |
777 | mutex_unlock(&trace_types_lock); |
778 | ||
dac74940 SR |
779 | if (ret || !default_bootup_tracer) |
780 | goto out_unlock; | |
781 | ||
ee6c2c1b | 782 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
783 | goto out_unlock; |
784 | ||
785 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
786 | /* Do we want this tracer to start on bootup? */ | |
787 | tracing_set_tracer(type->name); | |
788 | default_bootup_tracer = NULL; | |
789 | /* disable other selftests, since this will break it. */ | |
790 | tracing_selftest_disabled = 1; | |
b2821ae6 | 791 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
792 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
793 | type->name); | |
b2821ae6 | 794 | #endif |
b2821ae6 | 795 | |
dac74940 | 796 | out_unlock: |
b2821ae6 | 797 | lock_kernel(); |
bc0c38d1 SR |
798 | return ret; |
799 | } | |
800 | ||
801 | void unregister_tracer(struct tracer *type) | |
802 | { | |
803 | struct tracer **t; | |
bc0c38d1 SR |
804 | |
805 | mutex_lock(&trace_types_lock); | |
806 | for (t = &trace_types; *t; t = &(*t)->next) { | |
807 | if (*t == type) | |
808 | goto found; | |
809 | } | |
ee6c2c1b | 810 | pr_info("Tracer %s not registered\n", type->name); |
bc0c38d1 SR |
811 | goto out; |
812 | ||
813 | found: | |
814 | *t = (*t)->next; | |
b5db03c4 ACM |
815 | |
816 | if (type == current_trace && tracer_enabled) { | |
817 | tracer_enabled = 0; | |
818 | tracing_stop(); | |
819 | if (current_trace->stop) | |
820 | current_trace->stop(&global_trace); | |
821 | current_trace = &nop_trace; | |
822 | } | |
ee6c2c1b | 823 | out: |
bc0c38d1 SR |
824 | mutex_unlock(&trace_types_lock); |
825 | } | |
826 | ||
f633903a | 827 | static void __tracing_reset(struct trace_array *tr, int cpu) |
bc0c38d1 | 828 | { |
d769041f | 829 | ftrace_disable_cpu(); |
3928a8a2 | 830 | ring_buffer_reset_cpu(tr->buffer, cpu); |
d769041f | 831 | ftrace_enable_cpu(); |
bc0c38d1 SR |
832 | } |
833 | ||
f633903a SR |
834 | void tracing_reset(struct trace_array *tr, int cpu) |
835 | { | |
836 | struct ring_buffer *buffer = tr->buffer; | |
837 | ||
838 | ring_buffer_record_disable(buffer); | |
839 | ||
840 | /* Make sure all commits have finished */ | |
841 | synchronize_sched(); | |
842 | __tracing_reset(tr, cpu); | |
843 | ||
844 | ring_buffer_record_enable(buffer); | |
845 | } | |
846 | ||
213cc060 PE |
847 | void tracing_reset_online_cpus(struct trace_array *tr) |
848 | { | |
621968cd | 849 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
850 | int cpu; |
851 | ||
621968cd SR |
852 | ring_buffer_record_disable(buffer); |
853 | ||
854 | /* Make sure all commits have finished */ | |
855 | synchronize_sched(); | |
856 | ||
213cc060 PE |
857 | tr->time_start = ftrace_now(tr->cpu); |
858 | ||
859 | for_each_online_cpu(cpu) | |
f633903a | 860 | __tracing_reset(tr, cpu); |
621968cd SR |
861 | |
862 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
863 | } |
864 | ||
9456f0fa SR |
865 | void tracing_reset_current(int cpu) |
866 | { | |
867 | tracing_reset(&global_trace, cpu); | |
868 | } | |
869 | ||
870 | void tracing_reset_current_online_cpus(void) | |
871 | { | |
872 | tracing_reset_online_cpus(&global_trace); | |
873 | } | |
874 | ||
bc0c38d1 | 875 | #define SAVED_CMDLINES 128 |
2c7eea4c | 876 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
877 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
878 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
879 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
880 | static int cmdline_idx; | |
edc35bd7 | 881 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 882 | |
25b0b44a | 883 | /* temporary disable recording */ |
4fd27358 | 884 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
885 | |
886 | static void trace_init_cmdlines(void) | |
887 | { | |
2c7eea4c TG |
888 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
889 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
890 | cmdline_idx = 0; |
891 | } | |
892 | ||
b5130b1e CE |
893 | int is_tracing_stopped(void) |
894 | { | |
895 | return trace_stop_count; | |
896 | } | |
897 | ||
69bb54ec SR |
898 | /** |
899 | * ftrace_off_permanent - disable all ftrace code permanently | |
900 | * | |
901 | * This should only be called when a serious anomally has | |
902 | * been detected. This will turn off the function tracing, | |
903 | * ring buffers, and other tracing utilites. It takes no | |
904 | * locks and can be called from any context. | |
905 | */ | |
906 | void ftrace_off_permanent(void) | |
907 | { | |
908 | tracing_disabled = 1; | |
909 | ftrace_stop(); | |
910 | tracing_off_permanent(); | |
911 | } | |
912 | ||
0f048701 SR |
913 | /** |
914 | * tracing_start - quick start of the tracer | |
915 | * | |
916 | * If tracing is enabled but was stopped by tracing_stop, | |
917 | * this will start the tracer back up. | |
918 | */ | |
919 | void tracing_start(void) | |
920 | { | |
921 | struct ring_buffer *buffer; | |
922 | unsigned long flags; | |
923 | ||
924 | if (tracing_disabled) | |
925 | return; | |
926 | ||
927 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
928 | if (--trace_stop_count) { |
929 | if (trace_stop_count < 0) { | |
930 | /* Someone screwed up their debugging */ | |
931 | WARN_ON_ONCE(1); | |
932 | trace_stop_count = 0; | |
933 | } | |
0f048701 SR |
934 | goto out; |
935 | } | |
936 | ||
937 | ||
938 | buffer = global_trace.buffer; | |
939 | if (buffer) | |
940 | ring_buffer_record_enable(buffer); | |
941 | ||
942 | buffer = max_tr.buffer; | |
943 | if (buffer) | |
944 | ring_buffer_record_enable(buffer); | |
945 | ||
946 | ftrace_start(); | |
947 | out: | |
948 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
949 | } | |
950 | ||
951 | /** | |
952 | * tracing_stop - quick stop of the tracer | |
953 | * | |
954 | * Light weight way to stop tracing. Use in conjunction with | |
955 | * tracing_start. | |
956 | */ | |
957 | void tracing_stop(void) | |
958 | { | |
959 | struct ring_buffer *buffer; | |
960 | unsigned long flags; | |
961 | ||
962 | ftrace_stop(); | |
963 | spin_lock_irqsave(&tracing_start_lock, flags); | |
964 | if (trace_stop_count++) | |
965 | goto out; | |
966 | ||
967 | buffer = global_trace.buffer; | |
968 | if (buffer) | |
969 | ring_buffer_record_disable(buffer); | |
970 | ||
971 | buffer = max_tr.buffer; | |
972 | if (buffer) | |
973 | ring_buffer_record_disable(buffer); | |
974 | ||
975 | out: | |
976 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
977 | } | |
978 | ||
e309b41d | 979 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 980 | |
e309b41d | 981 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 982 | { |
a635cf04 | 983 | unsigned pid, idx; |
bc0c38d1 SR |
984 | |
985 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
986 | return; | |
987 | ||
988 | /* | |
989 | * It's not the end of the world if we don't get | |
990 | * the lock, but we also don't want to spin | |
991 | * nor do we want to disable interrupts, | |
992 | * so if we miss here, then better luck next time. | |
993 | */ | |
0199c4e6 | 994 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
995 | return; |
996 | ||
997 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 998 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
999 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1000 | ||
a635cf04 CE |
1001 | /* |
1002 | * Check whether the cmdline buffer at idx has a pid | |
1003 | * mapped. We are going to overwrite that entry so we | |
1004 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1005 | * would read the new comm for the old pid. | |
1006 | */ | |
1007 | pid = map_cmdline_to_pid[idx]; | |
1008 | if (pid != NO_CMDLINE_MAP) | |
1009 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1010 | |
a635cf04 | 1011 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1012 | map_pid_to_cmdline[tsk->pid] = idx; |
1013 | ||
1014 | cmdline_idx = idx; | |
1015 | } | |
1016 | ||
1017 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1018 | ||
0199c4e6 | 1019 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1020 | } |
1021 | ||
4ca53085 | 1022 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1023 | { |
bc0c38d1 SR |
1024 | unsigned map; |
1025 | ||
4ca53085 SR |
1026 | if (!pid) { |
1027 | strcpy(comm, "<idle>"); | |
1028 | return; | |
1029 | } | |
bc0c38d1 | 1030 | |
74bf4076 SR |
1031 | if (WARN_ON_ONCE(pid < 0)) { |
1032 | strcpy(comm, "<XXX>"); | |
1033 | return; | |
1034 | } | |
1035 | ||
4ca53085 SR |
1036 | if (pid > PID_MAX_DEFAULT) { |
1037 | strcpy(comm, "<...>"); | |
1038 | return; | |
1039 | } | |
bc0c38d1 | 1040 | |
5b6045a9 | 1041 | preempt_disable(); |
0199c4e6 | 1042 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1043 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1044 | if (map != NO_CMDLINE_MAP) |
1045 | strcpy(comm, saved_cmdlines[map]); | |
1046 | else | |
1047 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1048 | |
0199c4e6 | 1049 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1050 | preempt_enable(); |
bc0c38d1 SR |
1051 | } |
1052 | ||
e309b41d | 1053 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1054 | { |
18aecd36 TG |
1055 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
1056 | !tracing_is_on()) | |
bc0c38d1 SR |
1057 | return; |
1058 | ||
1059 | trace_save_cmdline(tsk); | |
1060 | } | |
1061 | ||
45dcd8b8 | 1062 | void |
38697053 SR |
1063 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1064 | int pc) | |
bc0c38d1 SR |
1065 | { |
1066 | struct task_struct *tsk = current; | |
bc0c38d1 | 1067 | |
777e208d SR |
1068 | entry->preempt_count = pc & 0xff; |
1069 | entry->pid = (tsk) ? tsk->pid : 0; | |
637e7e86 | 1070 | entry->lock_depth = (tsk) ? tsk->lock_depth : 0; |
777e208d | 1071 | entry->flags = |
9244489a | 1072 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1073 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1074 | #else |
1075 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1076 | #endif | |
bc0c38d1 SR |
1077 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1078 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1079 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1080 | } | |
f413cdb8 | 1081 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1082 | |
e77405ad SR |
1083 | struct ring_buffer_event * |
1084 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1085 | int type, | |
1086 | unsigned long len, | |
1087 | unsigned long flags, int pc) | |
51a763dd ACM |
1088 | { |
1089 | struct ring_buffer_event *event; | |
1090 | ||
e77405ad | 1091 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1092 | if (event != NULL) { |
1093 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1094 | ||
1095 | tracing_generic_entry_update(ent, flags, pc); | |
1096 | ent->type = type; | |
1097 | } | |
1098 | ||
1099 | return event; | |
1100 | } | |
51a763dd | 1101 | |
e77405ad SR |
1102 | static inline void |
1103 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1104 | struct ring_buffer_event *event, | |
1105 | unsigned long flags, int pc, | |
1106 | int wake) | |
51a763dd | 1107 | { |
e77405ad | 1108 | ring_buffer_unlock_commit(buffer, event); |
51a763dd | 1109 | |
e77405ad SR |
1110 | ftrace_trace_stack(buffer, flags, 6, pc); |
1111 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1112 | |
1113 | if (wake) | |
1114 | trace_wake_up(); | |
1115 | } | |
1116 | ||
e77405ad SR |
1117 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1118 | struct ring_buffer_event *event, | |
1119 | unsigned long flags, int pc) | |
07edf712 | 1120 | { |
e77405ad | 1121 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
51a763dd ACM |
1122 | } |
1123 | ||
ef5580d0 | 1124 | struct ring_buffer_event * |
e77405ad SR |
1125 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1126 | int type, unsigned long len, | |
ef5580d0 SR |
1127 | unsigned long flags, int pc) |
1128 | { | |
e77405ad SR |
1129 | *current_rb = global_trace.buffer; |
1130 | return trace_buffer_lock_reserve(*current_rb, | |
ef5580d0 SR |
1131 | type, len, flags, pc); |
1132 | } | |
94487d6d | 1133 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1134 | |
e77405ad SR |
1135 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1136 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1137 | unsigned long flags, int pc) |
1138 | { | |
e77405ad | 1139 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
07edf712 | 1140 | } |
94487d6d | 1141 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1142 | |
e77405ad SR |
1143 | void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer, |
1144 | struct ring_buffer_event *event, | |
1145 | unsigned long flags, int pc) | |
07edf712 | 1146 | { |
e77405ad | 1147 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 0); |
77d9f465 | 1148 | } |
94487d6d | 1149 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 | 1150 | |
e77405ad SR |
1151 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1152 | struct ring_buffer_event *event) | |
77d9f465 | 1153 | { |
e77405ad | 1154 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1155 | } |
12acd473 | 1156 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1157 | |
e309b41d | 1158 | void |
7be42151 | 1159 | trace_function(struct trace_array *tr, |
38697053 SR |
1160 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1161 | int pc) | |
bc0c38d1 | 1162 | { |
e1112b4d | 1163 | struct ftrace_event_call *call = &event_function; |
e77405ad | 1164 | struct ring_buffer *buffer = tr->buffer; |
3928a8a2 | 1165 | struct ring_buffer_event *event; |
777e208d | 1166 | struct ftrace_entry *entry; |
bc0c38d1 | 1167 | |
d769041f | 1168 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1169 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1170 | return; |
1171 | ||
e77405ad | 1172 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1173 | flags, pc); |
3928a8a2 SR |
1174 | if (!event) |
1175 | return; | |
1176 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1177 | entry->ip = ip; |
1178 | entry->parent_ip = parent_ip; | |
e1112b4d | 1179 | |
e77405ad SR |
1180 | if (!filter_check_discard(call, entry, buffer, event)) |
1181 | ring_buffer_unlock_commit(buffer, event); | |
bc0c38d1 SR |
1182 | } |
1183 | ||
e309b41d | 1184 | void |
2e0f5761 | 1185 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1186 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1187 | int pc) | |
2e0f5761 IM |
1188 | { |
1189 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1190 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1191 | } |
1192 | ||
c0a0d0d3 | 1193 | #ifdef CONFIG_STACKTRACE |
e77405ad | 1194 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 SR |
1195 | unsigned long flags, |
1196 | int skip, int pc) | |
86387f7e | 1197 | { |
e1112b4d | 1198 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1199 | struct ring_buffer_event *event; |
777e208d | 1200 | struct stack_entry *entry; |
86387f7e IM |
1201 | struct stack_trace trace; |
1202 | ||
e77405ad | 1203 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
51a763dd | 1204 | sizeof(*entry), flags, pc); |
3928a8a2 SR |
1205 | if (!event) |
1206 | return; | |
1207 | entry = ring_buffer_event_data(event); | |
777e208d | 1208 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
1209 | |
1210 | trace.nr_entries = 0; | |
1211 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1212 | trace.skip = skip; | |
777e208d | 1213 | trace.entries = entry->caller; |
86387f7e IM |
1214 | |
1215 | save_stack_trace(&trace); | |
e77405ad SR |
1216 | if (!filter_check_discard(call, entry, buffer, event)) |
1217 | ring_buffer_unlock_commit(buffer, event); | |
f0a920d5 IM |
1218 | } |
1219 | ||
e77405ad SR |
1220 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1221 | int skip, int pc) | |
53614991 SR |
1222 | { |
1223 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1224 | return; | |
1225 | ||
e77405ad | 1226 | __ftrace_trace_stack(buffer, flags, skip, pc); |
53614991 SR |
1227 | } |
1228 | ||
c0a0d0d3 FW |
1229 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1230 | int pc) | |
38697053 | 1231 | { |
e77405ad | 1232 | __ftrace_trace_stack(tr->buffer, flags, skip, pc); |
38697053 SR |
1233 | } |
1234 | ||
03889384 SR |
1235 | /** |
1236 | * trace_dump_stack - record a stack back trace in the trace buffer | |
1237 | */ | |
1238 | void trace_dump_stack(void) | |
1239 | { | |
1240 | unsigned long flags; | |
1241 | ||
1242 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1243 | return; |
03889384 SR |
1244 | |
1245 | local_save_flags(flags); | |
1246 | ||
1247 | /* skipping 3 traces, seems to get us at the caller of this function */ | |
1248 | __ftrace_trace_stack(global_trace.buffer, flags, 3, preempt_count()); | |
1249 | } | |
1250 | ||
e77405ad SR |
1251 | void |
1252 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1253 | { |
e1112b4d | 1254 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1255 | struct ring_buffer_event *event; |
02b67518 TE |
1256 | struct userstack_entry *entry; |
1257 | struct stack_trace trace; | |
02b67518 TE |
1258 | |
1259 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1260 | return; | |
1261 | ||
e77405ad | 1262 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1263 | sizeof(*entry), flags, pc); |
02b67518 TE |
1264 | if (!event) |
1265 | return; | |
1266 | entry = ring_buffer_event_data(event); | |
02b67518 | 1267 | |
48659d31 | 1268 | entry->tgid = current->tgid; |
02b67518 TE |
1269 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1270 | ||
1271 | trace.nr_entries = 0; | |
1272 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1273 | trace.skip = 0; | |
1274 | trace.entries = entry->caller; | |
1275 | ||
1276 | save_stack_trace_user(&trace); | |
e77405ad SR |
1277 | if (!filter_check_discard(call, entry, buffer, event)) |
1278 | ring_buffer_unlock_commit(buffer, event); | |
02b67518 TE |
1279 | } |
1280 | ||
4fd27358 HE |
1281 | #ifdef UNUSED |
1282 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1283 | { |
7be42151 | 1284 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1285 | } |
4fd27358 | 1286 | #endif /* UNUSED */ |
02b67518 | 1287 | |
c0a0d0d3 FW |
1288 | #endif /* CONFIG_STACKTRACE */ |
1289 | ||
38697053 | 1290 | static void |
7be42151 | 1291 | ftrace_trace_special(void *__tr, |
38697053 SR |
1292 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1293 | int pc) | |
a4feb834 | 1294 | { |
60ba7702 | 1295 | struct ftrace_event_call *call = &event_special; |
3928a8a2 | 1296 | struct ring_buffer_event *event; |
a4feb834 | 1297 | struct trace_array *tr = __tr; |
e77405ad | 1298 | struct ring_buffer *buffer = tr->buffer; |
777e208d | 1299 | struct special_entry *entry; |
a4feb834 | 1300 | |
e77405ad | 1301 | event = trace_buffer_lock_reserve(buffer, TRACE_SPECIAL, |
51a763dd | 1302 | sizeof(*entry), 0, pc); |
3928a8a2 SR |
1303 | if (!event) |
1304 | return; | |
1305 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1306 | entry->arg1 = arg1; |
1307 | entry->arg2 = arg2; | |
1308 | entry->arg3 = arg3; | |
60ba7702 SR |
1309 | |
1310 | if (!filter_check_discard(call, entry, buffer, event)) | |
1311 | trace_buffer_unlock_commit(buffer, event, 0, pc); | |
a4feb834 IM |
1312 | } |
1313 | ||
38697053 SR |
1314 | void |
1315 | __trace_special(void *__tr, void *__data, | |
1316 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1317 | { | |
7be42151 | 1318 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1319 | } |
1320 | ||
4902f884 SR |
1321 | void |
1322 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1323 | { | |
1324 | struct trace_array *tr = &global_trace; | |
1325 | struct trace_array_cpu *data; | |
5aa1ba6a | 1326 | unsigned long flags; |
4902f884 | 1327 | int cpu; |
38697053 | 1328 | int pc; |
4902f884 | 1329 | |
c76f0694 | 1330 | if (tracing_disabled) |
4902f884 SR |
1331 | return; |
1332 | ||
38697053 | 1333 | pc = preempt_count(); |
5aa1ba6a | 1334 | local_irq_save(flags); |
4902f884 SR |
1335 | cpu = raw_smp_processor_id(); |
1336 | data = tr->data[cpu]; | |
4902f884 | 1337 | |
5aa1ba6a | 1338 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1339 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1340 | |
5aa1ba6a SR |
1341 | atomic_dec(&data->disabled); |
1342 | local_irq_restore(flags); | |
4902f884 SR |
1343 | } |
1344 | ||
769b0441 | 1345 | /** |
48ead020 | 1346 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1347 | * |
1348 | */ | |
40ce74f1 | 1349 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1350 | { |
445c8951 | 1351 | static arch_spinlock_t trace_buf_lock = |
edc35bd7 | 1352 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
769b0441 FW |
1353 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1354 | ||
e1112b4d | 1355 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1356 | struct ring_buffer_event *event; |
e77405ad | 1357 | struct ring_buffer *buffer; |
769b0441 FW |
1358 | struct trace_array *tr = &global_trace; |
1359 | struct trace_array_cpu *data; | |
48ead020 | 1360 | struct bprint_entry *entry; |
769b0441 | 1361 | unsigned long flags; |
3189cdb3 | 1362 | int disable; |
769b0441 FW |
1363 | int resched; |
1364 | int cpu, len = 0, size, pc; | |
1365 | ||
1366 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1367 | return 0; | |
1368 | ||
1369 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1370 | pause_graph_tracing(); | |
1371 | ||
1372 | pc = preempt_count(); | |
1373 | resched = ftrace_preempt_disable(); | |
1374 | cpu = raw_smp_processor_id(); | |
1375 | data = tr->data[cpu]; | |
1376 | ||
3189cdb3 SR |
1377 | disable = atomic_inc_return(&data->disabled); |
1378 | if (unlikely(disable != 1)) | |
769b0441 FW |
1379 | goto out; |
1380 | ||
80370cb7 SR |
1381 | /* Lockdep uses trace_printk for lock tracing */ |
1382 | local_irq_save(flags); | |
0199c4e6 | 1383 | arch_spin_lock(&trace_buf_lock); |
769b0441 FW |
1384 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1385 | ||
1386 | if (len > TRACE_BUF_SIZE || len < 0) | |
1387 | goto out_unlock; | |
1388 | ||
1389 | size = sizeof(*entry) + sizeof(u32) * len; | |
e77405ad SR |
1390 | buffer = tr->buffer; |
1391 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, | |
1392 | flags, pc); | |
769b0441 FW |
1393 | if (!event) |
1394 | goto out_unlock; | |
1395 | entry = ring_buffer_event_data(event); | |
1396 | entry->ip = ip; | |
769b0441 FW |
1397 | entry->fmt = fmt; |
1398 | ||
1399 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
d931369b | 1400 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1401 | ring_buffer_unlock_commit(buffer, event); |
d931369b SR |
1402 | ftrace_trace_stack(buffer, flags, 6, pc); |
1403 | } | |
769b0441 FW |
1404 | |
1405 | out_unlock: | |
0199c4e6 | 1406 | arch_spin_unlock(&trace_buf_lock); |
80370cb7 | 1407 | local_irq_restore(flags); |
769b0441 FW |
1408 | |
1409 | out: | |
3189cdb3 | 1410 | atomic_dec_return(&data->disabled); |
769b0441 FW |
1411 | ftrace_preempt_enable(resched); |
1412 | unpause_graph_tracing(); | |
1413 | ||
1414 | return len; | |
1415 | } | |
48ead020 FW |
1416 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1417 | ||
659372d3 SR |
1418 | int trace_array_printk(struct trace_array *tr, |
1419 | unsigned long ip, const char *fmt, ...) | |
1420 | { | |
1421 | int ret; | |
1422 | va_list ap; | |
1423 | ||
1424 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1425 | return 0; | |
1426 | ||
1427 | va_start(ap, fmt); | |
1428 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
1429 | va_end(ap); | |
1430 | return ret; | |
1431 | } | |
1432 | ||
1433 | int trace_array_vprintk(struct trace_array *tr, | |
1434 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 1435 | { |
edc35bd7 | 1436 | static arch_spinlock_t trace_buf_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
48ead020 FW |
1437 | static char trace_buf[TRACE_BUF_SIZE]; |
1438 | ||
e1112b4d | 1439 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1440 | struct ring_buffer_event *event; |
e77405ad | 1441 | struct ring_buffer *buffer; |
48ead020 FW |
1442 | struct trace_array_cpu *data; |
1443 | int cpu, len = 0, size, pc; | |
1444 | struct print_entry *entry; | |
1445 | unsigned long irq_flags; | |
3189cdb3 | 1446 | int disable; |
48ead020 FW |
1447 | |
1448 | if (tracing_disabled || tracing_selftest_running) | |
1449 | return 0; | |
1450 | ||
1451 | pc = preempt_count(); | |
1452 | preempt_disable_notrace(); | |
1453 | cpu = raw_smp_processor_id(); | |
1454 | data = tr->data[cpu]; | |
1455 | ||
3189cdb3 SR |
1456 | disable = atomic_inc_return(&data->disabled); |
1457 | if (unlikely(disable != 1)) | |
48ead020 FW |
1458 | goto out; |
1459 | ||
1460 | pause_graph_tracing(); | |
1461 | raw_local_irq_save(irq_flags); | |
0199c4e6 | 1462 | arch_spin_lock(&trace_buf_lock); |
f2942487 | 1463 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
48ead020 FW |
1464 | |
1465 | size = sizeof(*entry) + len + 1; | |
e77405ad SR |
1466 | buffer = tr->buffer; |
1467 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
1468 | irq_flags, pc); | |
48ead020 FW |
1469 | if (!event) |
1470 | goto out_unlock; | |
1471 | entry = ring_buffer_event_data(event); | |
c13d2f7c | 1472 | entry->ip = ip; |
48ead020 FW |
1473 | |
1474 | memcpy(&entry->buf, trace_buf, len); | |
c13d2f7c | 1475 | entry->buf[len] = '\0'; |
d931369b | 1476 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1477 | ring_buffer_unlock_commit(buffer, event); |
d931369b SR |
1478 | ftrace_trace_stack(buffer, irq_flags, 6, pc); |
1479 | } | |
48ead020 FW |
1480 | |
1481 | out_unlock: | |
0199c4e6 | 1482 | arch_spin_unlock(&trace_buf_lock); |
48ead020 FW |
1483 | raw_local_irq_restore(irq_flags); |
1484 | unpause_graph_tracing(); | |
1485 | out: | |
3189cdb3 | 1486 | atomic_dec_return(&data->disabled); |
48ead020 FW |
1487 | preempt_enable_notrace(); |
1488 | ||
1489 | return len; | |
1490 | } | |
659372d3 SR |
1491 | |
1492 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) | |
1493 | { | |
a813a159 | 1494 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 1495 | } |
769b0441 FW |
1496 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1497 | ||
bc0c38d1 SR |
1498 | enum trace_file_type { |
1499 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1500 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1501 | }; |
1502 | ||
e2ac8ef5 | 1503 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1504 | { |
d769041f SR |
1505 | /* Don't allow ftrace to trace into the ring buffers */ |
1506 | ftrace_disable_cpu(); | |
1507 | ||
5a90f577 | 1508 | iter->idx++; |
d769041f SR |
1509 | if (iter->buffer_iter[iter->cpu]) |
1510 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1511 | ||
1512 | ftrace_enable_cpu(); | |
5a90f577 SR |
1513 | } |
1514 | ||
e309b41d | 1515 | static struct trace_entry * |
3928a8a2 | 1516 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1517 | { |
3928a8a2 SR |
1518 | struct ring_buffer_event *event; |
1519 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1520 | |
d769041f SR |
1521 | /* Don't allow ftrace to trace into the ring buffers */ |
1522 | ftrace_disable_cpu(); | |
1523 | ||
1524 | if (buf_iter) | |
1525 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1526 | else | |
1527 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1528 | ||
1529 | ftrace_enable_cpu(); | |
1530 | ||
3928a8a2 | 1531 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1532 | } |
d769041f | 1533 | |
dd0e545f | 1534 | static struct trace_entry * |
3928a8a2 | 1535 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1536 | { |
3928a8a2 | 1537 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1538 | struct trace_entry *ent, *next = NULL; |
b04cc6b1 | 1539 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1540 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1541 | int next_cpu = -1; |
1542 | int cpu; | |
1543 | ||
b04cc6b1 FW |
1544 | /* |
1545 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1546 | * all cpu and peek directly. | |
1547 | */ | |
1548 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1549 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1550 | return NULL; | |
1551 | ent = peek_next_entry(iter, cpu_file, ent_ts); | |
1552 | if (ent_cpu) | |
1553 | *ent_cpu = cpu_file; | |
1554 | ||
1555 | return ent; | |
1556 | } | |
1557 | ||
ab46428c | 1558 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1559 | |
3928a8a2 SR |
1560 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1561 | continue; | |
dd0e545f | 1562 | |
3928a8a2 | 1563 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1564 | |
cdd31cd2 IM |
1565 | /* |
1566 | * Pick the entry with the smallest timestamp: | |
1567 | */ | |
3928a8a2 | 1568 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1569 | next = ent; |
1570 | next_cpu = cpu; | |
3928a8a2 | 1571 | next_ts = ts; |
bc0c38d1 SR |
1572 | } |
1573 | } | |
1574 | ||
1575 | if (ent_cpu) | |
1576 | *ent_cpu = next_cpu; | |
1577 | ||
3928a8a2 SR |
1578 | if (ent_ts) |
1579 | *ent_ts = next_ts; | |
1580 | ||
bc0c38d1 SR |
1581 | return next; |
1582 | } | |
1583 | ||
dd0e545f | 1584 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1585 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1586 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1587 | { |
3928a8a2 | 1588 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1589 | } |
1590 | ||
1591 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1592 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1593 | { | |
3928a8a2 | 1594 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1595 | |
3928a8a2 | 1596 | if (iter->ent) |
e2ac8ef5 | 1597 | trace_iterator_increment(iter); |
dd0e545f | 1598 | |
3928a8a2 | 1599 | return iter->ent ? iter : NULL; |
b3806b43 | 1600 | } |
bc0c38d1 | 1601 | |
e309b41d | 1602 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1603 | { |
d769041f SR |
1604 | /* Don't allow ftrace to trace into the ring buffers */ |
1605 | ftrace_disable_cpu(); | |
3928a8a2 | 1606 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1607 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1608 | } |
1609 | ||
e309b41d | 1610 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1611 | { |
1612 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1613 | int i = (int)*pos; |
4e3c3333 | 1614 | void *ent; |
bc0c38d1 | 1615 | |
a63ce5b3 SR |
1616 | WARN_ON_ONCE(iter->leftover); |
1617 | ||
bc0c38d1 SR |
1618 | (*pos)++; |
1619 | ||
1620 | /* can't go backwards */ | |
1621 | if (iter->idx > i) | |
1622 | return NULL; | |
1623 | ||
1624 | if (iter->idx < 0) | |
1625 | ent = find_next_entry_inc(iter); | |
1626 | else | |
1627 | ent = iter; | |
1628 | ||
1629 | while (ent && iter->idx < i) | |
1630 | ent = find_next_entry_inc(iter); | |
1631 | ||
1632 | iter->pos = *pos; | |
1633 | ||
bc0c38d1 SR |
1634 | return ent; |
1635 | } | |
1636 | ||
2f26ebd5 SR |
1637 | static void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
1638 | { | |
1639 | struct trace_array *tr = iter->tr; | |
1640 | struct ring_buffer_event *event; | |
1641 | struct ring_buffer_iter *buf_iter; | |
1642 | unsigned long entries = 0; | |
1643 | u64 ts; | |
1644 | ||
1645 | tr->data[cpu]->skipped_entries = 0; | |
1646 | ||
1647 | if (!iter->buffer_iter[cpu]) | |
1648 | return; | |
1649 | ||
1650 | buf_iter = iter->buffer_iter[cpu]; | |
1651 | ring_buffer_iter_reset(buf_iter); | |
1652 | ||
1653 | /* | |
1654 | * We could have the case with the max latency tracers | |
1655 | * that a reset never took place on a cpu. This is evident | |
1656 | * by the timestamp being before the start of the buffer. | |
1657 | */ | |
1658 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
1659 | if (ts >= iter->tr->time_start) | |
1660 | break; | |
1661 | entries++; | |
1662 | ring_buffer_read(buf_iter, NULL); | |
1663 | } | |
1664 | ||
1665 | tr->data[cpu]->skipped_entries = entries; | |
1666 | } | |
1667 | ||
d7350c3f | 1668 | /* |
d7350c3f FW |
1669 | * The current tracer is copied to avoid a global locking |
1670 | * all around. | |
1671 | */ | |
bc0c38d1 SR |
1672 | static void *s_start(struct seq_file *m, loff_t *pos) |
1673 | { | |
1674 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1675 | static struct tracer *old_tracer; |
b04cc6b1 | 1676 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1677 | void *p = NULL; |
1678 | loff_t l = 0; | |
3928a8a2 | 1679 | int cpu; |
bc0c38d1 | 1680 | |
d7350c3f | 1681 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1682 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1683 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1684 | old_tracer = current_trace; | |
1685 | *iter->trace = *current_trace; | |
d15f57f2 | 1686 | } |
d7350c3f | 1687 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1688 | |
1689 | atomic_inc(&trace_record_cmdline_disabled); | |
1690 | ||
bc0c38d1 SR |
1691 | if (*pos != iter->pos) { |
1692 | iter->ent = NULL; | |
1693 | iter->cpu = 0; | |
1694 | iter->idx = -1; | |
1695 | ||
d769041f SR |
1696 | ftrace_disable_cpu(); |
1697 | ||
b04cc6b1 FW |
1698 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1699 | for_each_tracing_cpu(cpu) | |
2f26ebd5 | 1700 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 1701 | } else |
2f26ebd5 | 1702 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 1703 | |
d769041f SR |
1704 | ftrace_enable_cpu(); |
1705 | ||
bc0c38d1 SR |
1706 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1707 | ; | |
1708 | ||
1709 | } else { | |
a63ce5b3 SR |
1710 | /* |
1711 | * If we overflowed the seq_file before, then we want | |
1712 | * to just reuse the trace_seq buffer again. | |
1713 | */ | |
1714 | if (iter->leftover) | |
1715 | p = iter; | |
1716 | else { | |
1717 | l = *pos - 1; | |
1718 | p = s_next(m, p, &l); | |
1719 | } | |
bc0c38d1 SR |
1720 | } |
1721 | ||
4f535968 | 1722 | trace_event_read_lock(); |
7e53bd42 | 1723 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
1724 | return p; |
1725 | } | |
1726 | ||
1727 | static void s_stop(struct seq_file *m, void *p) | |
1728 | { | |
7e53bd42 LJ |
1729 | struct trace_iterator *iter = m->private; |
1730 | ||
bc0c38d1 | 1731 | atomic_dec(&trace_record_cmdline_disabled); |
7e53bd42 | 1732 | trace_access_unlock(iter->cpu_file); |
4f535968 | 1733 | trace_event_read_unlock(); |
bc0c38d1 SR |
1734 | } |
1735 | ||
e309b41d | 1736 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1737 | { |
a6168353 ME |
1738 | seq_puts(m, "# _------=> CPU# \n"); |
1739 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1740 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1741 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1742 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
637e7e86 SR |
1743 | seq_puts(m, "# |||| /_--=> lock-depth \n"); |
1744 | seq_puts(m, "# |||||/ delay \n"); | |
1745 | seq_puts(m, "# cmd pid |||||| time | caller \n"); | |
1746 | seq_puts(m, "# \\ / |||||| \\ | / \n"); | |
bc0c38d1 SR |
1747 | } |
1748 | ||
e309b41d | 1749 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1750 | { |
a6168353 ME |
1751 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1752 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1753 | } |
1754 | ||
1755 | ||
e309b41d | 1756 | static void |
bc0c38d1 SR |
1757 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1758 | { | |
1759 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1760 | struct trace_array *tr = iter->tr; | |
1761 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1762 | struct tracer *type = current_trace; | |
2f26ebd5 SR |
1763 | unsigned long entries = 0; |
1764 | unsigned long total = 0; | |
1765 | unsigned long count; | |
bc0c38d1 | 1766 | const char *name = "preemption"; |
2f26ebd5 | 1767 | int cpu; |
bc0c38d1 SR |
1768 | |
1769 | if (type) | |
1770 | name = type->name; | |
1771 | ||
2f26ebd5 SR |
1772 | |
1773 | for_each_tracing_cpu(cpu) { | |
1774 | count = ring_buffer_entries_cpu(tr->buffer, cpu); | |
1775 | /* | |
1776 | * If this buffer has skipped entries, then we hold all | |
1777 | * entries for the trace and we need to ignore the | |
1778 | * ones before the time stamp. | |
1779 | */ | |
1780 | if (tr->data[cpu]->skipped_entries) { | |
1781 | count -= tr->data[cpu]->skipped_entries; | |
1782 | /* total is the same as the entries */ | |
1783 | total += count; | |
1784 | } else | |
1785 | total += count + | |
1786 | ring_buffer_overrun_cpu(tr->buffer, cpu); | |
1787 | entries += count; | |
1788 | } | |
bc0c38d1 | 1789 | |
888b55dc | 1790 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1791 | name, UTS_RELEASE); |
888b55dc | 1792 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1793 | "---------------------------------\n"); |
888b55dc | 1794 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1795 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1796 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1797 | entries, |
4c11d7ae | 1798 | total, |
bc0c38d1 SR |
1799 | tr->cpu, |
1800 | #if defined(CONFIG_PREEMPT_NONE) | |
1801 | "server", | |
1802 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1803 | "desktop", | |
b5c21b45 | 1804 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1805 | "preempt", |
1806 | #else | |
1807 | "unknown", | |
1808 | #endif | |
1809 | /* These are reserved for later use */ | |
1810 | 0, 0, 0, 0); | |
1811 | #ifdef CONFIG_SMP | |
1812 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1813 | #else | |
1814 | seq_puts(m, ")\n"); | |
1815 | #endif | |
888b55dc KM |
1816 | seq_puts(m, "# -----------------\n"); |
1817 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1818 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1819 | data->comm, data->pid, data->uid, data->nice, | |
1820 | data->policy, data->rt_priority); | |
888b55dc | 1821 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1822 | |
1823 | if (data->critical_start) { | |
888b55dc | 1824 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1825 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1826 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1827 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1828 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1829 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 1830 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
1831 | } |
1832 | ||
888b55dc | 1833 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1834 | } |
1835 | ||
a309720c SR |
1836 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1837 | { | |
1838 | struct trace_seq *s = &iter->seq; | |
1839 | ||
12ef7d44 SR |
1840 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1841 | return; | |
1842 | ||
1843 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1844 | return; | |
1845 | ||
4462344e | 1846 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1847 | return; |
1848 | ||
2f26ebd5 SR |
1849 | if (iter->tr->data[iter->cpu]->skipped_entries) |
1850 | return; | |
1851 | ||
4462344e | 1852 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1853 | |
1854 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1855 | if (iter->idx > 1) | |
1856 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1857 | iter->cpu); | |
a309720c SR |
1858 | } |
1859 | ||
2c4f035f | 1860 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1861 | { |
214023c3 | 1862 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1863 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1864 | struct trace_entry *entry; |
f633cef0 | 1865 | struct trace_event *event; |
bc0c38d1 | 1866 | |
4e3c3333 | 1867 | entry = iter->ent; |
dd0e545f | 1868 | |
a309720c SR |
1869 | test_cpu_buff_start(iter); |
1870 | ||
c4a8e8be | 1871 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1872 | |
c4a8e8be | 1873 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1874 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1875 | if (!trace_print_lat_context(iter)) | |
1876 | goto partial; | |
1877 | } else { | |
1878 | if (!trace_print_context(iter)) | |
1879 | goto partial; | |
1880 | } | |
c4a8e8be | 1881 | } |
bc0c38d1 | 1882 | |
268ccda0 | 1883 | if (event) |
d9793bd8 ACM |
1884 | return event->trace(iter, sym_flags); |
1885 | ||
1886 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1887 | goto partial; | |
02b67518 | 1888 | |
2c4f035f | 1889 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1890 | partial: |
1891 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1892 | } |
1893 | ||
2c4f035f | 1894 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1895 | { |
1896 | struct trace_seq *s = &iter->seq; | |
1897 | struct trace_entry *entry; | |
f633cef0 | 1898 | struct trace_event *event; |
f9896bf3 IM |
1899 | |
1900 | entry = iter->ent; | |
dd0e545f | 1901 | |
c4a8e8be | 1902 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1903 | if (!trace_seq_printf(s, "%d %d %llu ", |
1904 | entry->pid, iter->cpu, iter->ts)) | |
1905 | goto partial; | |
c4a8e8be | 1906 | } |
f9896bf3 | 1907 | |
f633cef0 | 1908 | event = ftrace_find_event(entry->type); |
268ccda0 | 1909 | if (event) |
d9793bd8 ACM |
1910 | return event->raw(iter, 0); |
1911 | ||
1912 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1913 | goto partial; | |
777e208d | 1914 | |
2c4f035f | 1915 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1916 | partial: |
1917 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1918 | } |
1919 | ||
2c4f035f | 1920 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1921 | { |
1922 | struct trace_seq *s = &iter->seq; | |
1923 | unsigned char newline = '\n'; | |
1924 | struct trace_entry *entry; | |
f633cef0 | 1925 | struct trace_event *event; |
5e3ca0ec IM |
1926 | |
1927 | entry = iter->ent; | |
dd0e545f | 1928 | |
c4a8e8be FW |
1929 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1930 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1931 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1932 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1933 | } | |
5e3ca0ec | 1934 | |
f633cef0 | 1935 | event = ftrace_find_event(entry->type); |
268ccda0 | 1936 | if (event) { |
ae7462b4 | 1937 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1938 | if (ret != TRACE_TYPE_HANDLED) |
1939 | return ret; | |
1940 | } | |
7104f300 | 1941 | |
5e3ca0ec IM |
1942 | SEQ_PUT_FIELD_RET(s, newline); |
1943 | ||
2c4f035f | 1944 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1945 | } |
1946 | ||
2c4f035f | 1947 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1948 | { |
1949 | struct trace_seq *s = &iter->seq; | |
1950 | struct trace_entry *entry; | |
f633cef0 | 1951 | struct trace_event *event; |
cb0f12aa IM |
1952 | |
1953 | entry = iter->ent; | |
dd0e545f | 1954 | |
c4a8e8be FW |
1955 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1956 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1957 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1958 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1959 | } | |
cb0f12aa | 1960 | |
f633cef0 | 1961 | event = ftrace_find_event(entry->type); |
268ccda0 | 1962 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1963 | } |
1964 | ||
bc0c38d1 SR |
1965 | static int trace_empty(struct trace_iterator *iter) |
1966 | { | |
bc0c38d1 SR |
1967 | int cpu; |
1968 | ||
9aba60fe SR |
1969 | /* If we are looking at one CPU buffer, only check that one */ |
1970 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1971 | cpu = iter->cpu_file; | |
1972 | if (iter->buffer_iter[cpu]) { | |
1973 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1974 | return 0; | |
1975 | } else { | |
1976 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1977 | return 0; | |
1978 | } | |
1979 | return 1; | |
1980 | } | |
1981 | ||
ab46428c | 1982 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1983 | if (iter->buffer_iter[cpu]) { |
1984 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1985 | return 0; | |
1986 | } else { | |
1987 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1988 | return 0; | |
1989 | } | |
bc0c38d1 | 1990 | } |
d769041f | 1991 | |
797d3712 | 1992 | return 1; |
bc0c38d1 SR |
1993 | } |
1994 | ||
4f535968 | 1995 | /* Called with trace_event_read_lock() held. */ |
2c4f035f | 1996 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1997 | { |
2c4f035f FW |
1998 | enum print_line_t ret; |
1999 | ||
2000 | if (iter->trace && iter->trace->print_line) { | |
2001 | ret = iter->trace->print_line(iter); | |
2002 | if (ret != TRACE_TYPE_UNHANDLED) | |
2003 | return ret; | |
2004 | } | |
72829bc3 | 2005 | |
48ead020 FW |
2006 | if (iter->ent->type == TRACE_BPRINT && |
2007 | trace_flags & TRACE_ITER_PRINTK && | |
2008 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2009 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2010 | |
66896a85 FW |
2011 | if (iter->ent->type == TRACE_PRINT && |
2012 | trace_flags & TRACE_ITER_PRINTK && | |
2013 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2014 | return trace_print_printk_msg_only(iter); |
66896a85 | 2015 | |
cb0f12aa IM |
2016 | if (trace_flags & TRACE_ITER_BIN) |
2017 | return print_bin_fmt(iter); | |
2018 | ||
5e3ca0ec IM |
2019 | if (trace_flags & TRACE_ITER_HEX) |
2020 | return print_hex_fmt(iter); | |
2021 | ||
f9896bf3 IM |
2022 | if (trace_flags & TRACE_ITER_RAW) |
2023 | return print_raw_fmt(iter); | |
2024 | ||
f9896bf3 IM |
2025 | return print_trace_fmt(iter); |
2026 | } | |
2027 | ||
bc0c38d1 SR |
2028 | static int s_show(struct seq_file *m, void *v) |
2029 | { | |
2030 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2031 | int ret; |
bc0c38d1 SR |
2032 | |
2033 | if (iter->ent == NULL) { | |
2034 | if (iter->tr) { | |
2035 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2036 | seq_puts(m, "#\n"); | |
2037 | } | |
8bba1bf5 MM |
2038 | if (iter->trace && iter->trace->print_header) |
2039 | iter->trace->print_header(m); | |
2040 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
2041 | /* print nothing if the buffers are empty */ |
2042 | if (trace_empty(iter)) | |
2043 | return 0; | |
2044 | print_trace_header(m, iter); | |
2045 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2046 | print_lat_help_header(m); | |
2047 | } else { | |
2048 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2049 | print_func_help_header(m); | |
2050 | } | |
a63ce5b3 SR |
2051 | } else if (iter->leftover) { |
2052 | /* | |
2053 | * If we filled the seq_file buffer earlier, we | |
2054 | * want to just show it now. | |
2055 | */ | |
2056 | ret = trace_print_seq(m, &iter->seq); | |
2057 | ||
2058 | /* ret should this time be zero, but you never know */ | |
2059 | iter->leftover = ret; | |
2060 | ||
bc0c38d1 | 2061 | } else { |
f9896bf3 | 2062 | print_trace_line(iter); |
a63ce5b3 SR |
2063 | ret = trace_print_seq(m, &iter->seq); |
2064 | /* | |
2065 | * If we overflow the seq_file buffer, then it will | |
2066 | * ask us for this data again at start up. | |
2067 | * Use that instead. | |
2068 | * ret is 0 if seq_file write succeeded. | |
2069 | * -1 otherwise. | |
2070 | */ | |
2071 | iter->leftover = ret; | |
bc0c38d1 SR |
2072 | } |
2073 | ||
2074 | return 0; | |
2075 | } | |
2076 | ||
88e9d34c | 2077 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2078 | .start = s_start, |
2079 | .next = s_next, | |
2080 | .stop = s_stop, | |
2081 | .show = s_show, | |
bc0c38d1 SR |
2082 | }; |
2083 | ||
e309b41d | 2084 | static struct trace_iterator * |
85a2f9b4 | 2085 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 2086 | { |
b04cc6b1 | 2087 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 2088 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 2089 | struct trace_iterator *iter; |
3928a8a2 | 2090 | struct seq_file *m; |
85a2f9b4 | 2091 | int cpu, ret; |
bc0c38d1 | 2092 | |
85a2f9b4 SR |
2093 | if (tracing_disabled) |
2094 | return ERR_PTR(-ENODEV); | |
60a11774 | 2095 | |
bc0c38d1 | 2096 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
2097 | if (!iter) |
2098 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2099 | |
d7350c3f FW |
2100 | /* |
2101 | * We make a copy of the current tracer to avoid concurrent | |
2102 | * changes on it while we are reading. | |
2103 | */ | |
bc0c38d1 | 2104 | mutex_lock(&trace_types_lock); |
d7350c3f | 2105 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2106 | if (!iter->trace) |
d7350c3f | 2107 | goto fail; |
85a2f9b4 | 2108 | |
d7350c3f FW |
2109 | if (current_trace) |
2110 | *iter->trace = *current_trace; | |
2111 | ||
79f55997 | 2112 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2113 | goto fail; |
2114 | ||
bc0c38d1 SR |
2115 | if (current_trace && current_trace->print_max) |
2116 | iter->tr = &max_tr; | |
2117 | else | |
b04cc6b1 | 2118 | iter->tr = &global_trace; |
bc0c38d1 | 2119 | iter->pos = -1; |
d7350c3f | 2120 | mutex_init(&iter->mutex); |
b04cc6b1 | 2121 | iter->cpu_file = cpu_file; |
bc0c38d1 | 2122 | |
8bba1bf5 MM |
2123 | /* Notify the tracer early; before we stop tracing. */ |
2124 | if (iter->trace && iter->trace->open) | |
a93751ca | 2125 | iter->trace->open(iter); |
8bba1bf5 | 2126 | |
12ef7d44 SR |
2127 | /* Annotate start of buffers if we had overruns */ |
2128 | if (ring_buffer_overruns(iter->tr->buffer)) | |
2129 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
2130 | ||
2f26ebd5 SR |
2131 | /* stop the trace while dumping */ |
2132 | tracing_stop(); | |
2133 | ||
b04cc6b1 FW |
2134 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
2135 | for_each_tracing_cpu(cpu) { | |
12ef7d44 | 2136 | |
b04cc6b1 FW |
2137 | iter->buffer_iter[cpu] = |
2138 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
2f26ebd5 | 2139 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2140 | } |
2141 | } else { | |
2142 | cpu = iter->cpu_file; | |
3928a8a2 | 2143 | iter->buffer_iter[cpu] = |
b04cc6b1 | 2144 | ring_buffer_read_start(iter->tr->buffer, cpu); |
2f26ebd5 | 2145 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2146 | } |
2147 | ||
85a2f9b4 SR |
2148 | ret = seq_open(file, &tracer_seq_ops); |
2149 | if (ret < 0) { | |
2150 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 2151 | goto fail_buffer; |
85a2f9b4 | 2152 | } |
bc0c38d1 | 2153 | |
3928a8a2 SR |
2154 | m = file->private_data; |
2155 | m->private = iter; | |
bc0c38d1 | 2156 | |
bc0c38d1 SR |
2157 | mutex_unlock(&trace_types_lock); |
2158 | ||
bc0c38d1 | 2159 | return iter; |
3928a8a2 SR |
2160 | |
2161 | fail_buffer: | |
2162 | for_each_tracing_cpu(cpu) { | |
2163 | if (iter->buffer_iter[cpu]) | |
2164 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2165 | } | |
b0dfa978 | 2166 | free_cpumask_var(iter->started); |
2f26ebd5 | 2167 | tracing_start(); |
d7350c3f | 2168 | fail: |
3928a8a2 | 2169 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2170 | kfree(iter->trace); |
0bb943c7 | 2171 | kfree(iter); |
3928a8a2 | 2172 | |
85a2f9b4 | 2173 | return fail_ret; |
bc0c38d1 SR |
2174 | } |
2175 | ||
2176 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2177 | { | |
60a11774 SR |
2178 | if (tracing_disabled) |
2179 | return -ENODEV; | |
2180 | ||
bc0c38d1 SR |
2181 | filp->private_data = inode->i_private; |
2182 | return 0; | |
2183 | } | |
2184 | ||
4fd27358 | 2185 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
2186 | { |
2187 | struct seq_file *m = (struct seq_file *)file->private_data; | |
4acd4d00 | 2188 | struct trace_iterator *iter; |
3928a8a2 | 2189 | int cpu; |
bc0c38d1 | 2190 | |
4acd4d00 SR |
2191 | if (!(file->f_mode & FMODE_READ)) |
2192 | return 0; | |
2193 | ||
2194 | iter = m->private; | |
2195 | ||
bc0c38d1 | 2196 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
2197 | for_each_tracing_cpu(cpu) { |
2198 | if (iter->buffer_iter[cpu]) | |
2199 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2200 | } | |
2201 | ||
bc0c38d1 SR |
2202 | if (iter->trace && iter->trace->close) |
2203 | iter->trace->close(iter); | |
2204 | ||
2205 | /* reenable tracing if it was previously enabled */ | |
9036990d | 2206 | tracing_start(); |
bc0c38d1 SR |
2207 | mutex_unlock(&trace_types_lock); |
2208 | ||
2209 | seq_release(inode, file); | |
d7350c3f | 2210 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2211 | free_cpumask_var(iter->started); |
d7350c3f | 2212 | kfree(iter->trace); |
bc0c38d1 SR |
2213 | kfree(iter); |
2214 | return 0; | |
2215 | } | |
2216 | ||
2217 | static int tracing_open(struct inode *inode, struct file *file) | |
2218 | { | |
85a2f9b4 SR |
2219 | struct trace_iterator *iter; |
2220 | int ret = 0; | |
bc0c38d1 | 2221 | |
4acd4d00 SR |
2222 | /* If this file was open for write, then erase contents */ |
2223 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2224 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 2225 | long cpu = (long) inode->i_private; |
bc0c38d1 | 2226 | |
4acd4d00 SR |
2227 | if (cpu == TRACE_PIPE_ALL_CPU) |
2228 | tracing_reset_online_cpus(&global_trace); | |
2229 | else | |
2230 | tracing_reset(&global_trace, cpu); | |
2231 | } | |
bc0c38d1 | 2232 | |
4acd4d00 SR |
2233 | if (file->f_mode & FMODE_READ) { |
2234 | iter = __tracing_open(inode, file); | |
2235 | if (IS_ERR(iter)) | |
2236 | ret = PTR_ERR(iter); | |
2237 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2238 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2239 | } | |
bc0c38d1 SR |
2240 | return ret; |
2241 | } | |
2242 | ||
e309b41d | 2243 | static void * |
bc0c38d1 SR |
2244 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2245 | { | |
f129e965 | 2246 | struct tracer *t = v; |
bc0c38d1 SR |
2247 | |
2248 | (*pos)++; | |
2249 | ||
2250 | if (t) | |
2251 | t = t->next; | |
2252 | ||
bc0c38d1 SR |
2253 | return t; |
2254 | } | |
2255 | ||
2256 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2257 | { | |
f129e965 | 2258 | struct tracer *t; |
bc0c38d1 SR |
2259 | loff_t l = 0; |
2260 | ||
2261 | mutex_lock(&trace_types_lock); | |
f129e965 | 2262 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2263 | ; |
2264 | ||
2265 | return t; | |
2266 | } | |
2267 | ||
2268 | static void t_stop(struct seq_file *m, void *p) | |
2269 | { | |
2270 | mutex_unlock(&trace_types_lock); | |
2271 | } | |
2272 | ||
2273 | static int t_show(struct seq_file *m, void *v) | |
2274 | { | |
2275 | struct tracer *t = v; | |
2276 | ||
2277 | if (!t) | |
2278 | return 0; | |
2279 | ||
2280 | seq_printf(m, "%s", t->name); | |
2281 | if (t->next) | |
2282 | seq_putc(m, ' '); | |
2283 | else | |
2284 | seq_putc(m, '\n'); | |
2285 | ||
2286 | return 0; | |
2287 | } | |
2288 | ||
88e9d34c | 2289 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
2290 | .start = t_start, |
2291 | .next = t_next, | |
2292 | .stop = t_stop, | |
2293 | .show = t_show, | |
bc0c38d1 SR |
2294 | }; |
2295 | ||
2296 | static int show_traces_open(struct inode *inode, struct file *file) | |
2297 | { | |
60a11774 SR |
2298 | if (tracing_disabled) |
2299 | return -ENODEV; | |
2300 | ||
f129e965 | 2301 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2302 | } |
2303 | ||
4acd4d00 SR |
2304 | static ssize_t |
2305 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2306 | size_t count, loff_t *ppos) | |
2307 | { | |
2308 | return count; | |
2309 | } | |
2310 | ||
5e2336a0 | 2311 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2312 | .open = tracing_open, |
2313 | .read = seq_read, | |
4acd4d00 | 2314 | .write = tracing_write_stub, |
4bf39a94 IM |
2315 | .llseek = seq_lseek, |
2316 | .release = tracing_release, | |
bc0c38d1 SR |
2317 | }; |
2318 | ||
5e2336a0 | 2319 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2320 | .open = show_traces_open, |
2321 | .read = seq_read, | |
2322 | .release = seq_release, | |
2323 | }; | |
2324 | ||
36dfe925 IM |
2325 | /* |
2326 | * Only trace on a CPU if the bitmask is set: | |
2327 | */ | |
9e01c1b7 | 2328 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2329 | |
2330 | /* | |
2331 | * The tracer itself will not take this lock, but still we want | |
2332 | * to provide a consistent cpumask to user-space: | |
2333 | */ | |
2334 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2335 | ||
2336 | /* | |
2337 | * Temporary storage for the character representation of the | |
2338 | * CPU bitmask (and one more byte for the newline): | |
2339 | */ | |
2340 | static char mask_str[NR_CPUS + 1]; | |
2341 | ||
c7078de1 IM |
2342 | static ssize_t |
2343 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2344 | size_t count, loff_t *ppos) | |
2345 | { | |
36dfe925 | 2346 | int len; |
c7078de1 IM |
2347 | |
2348 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2349 | |
9e01c1b7 | 2350 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2351 | if (count - len < 2) { |
2352 | count = -EINVAL; | |
2353 | goto out_err; | |
2354 | } | |
2355 | len += sprintf(mask_str + len, "\n"); | |
2356 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2357 | ||
2358 | out_err: | |
c7078de1 IM |
2359 | mutex_unlock(&tracing_cpumask_update_lock); |
2360 | ||
2361 | return count; | |
2362 | } | |
2363 | ||
2364 | static ssize_t | |
2365 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2366 | size_t count, loff_t *ppos) | |
2367 | { | |
36dfe925 | 2368 | int err, cpu; |
9e01c1b7 RR |
2369 | cpumask_var_t tracing_cpumask_new; |
2370 | ||
2371 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2372 | return -ENOMEM; | |
c7078de1 | 2373 | |
9e01c1b7 | 2374 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2375 | if (err) |
36dfe925 IM |
2376 | goto err_unlock; |
2377 | ||
215368e8 LZ |
2378 | mutex_lock(&tracing_cpumask_update_lock); |
2379 | ||
a5e25883 | 2380 | local_irq_disable(); |
0199c4e6 | 2381 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 2382 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2383 | /* |
2384 | * Increase/decrease the disabled counter if we are | |
2385 | * about to flip a bit in the cpumask: | |
2386 | */ | |
9e01c1b7 RR |
2387 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2388 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2389 | atomic_inc(&global_trace.data[cpu]->disabled); |
2390 | } | |
9e01c1b7 RR |
2391 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2392 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2393 | atomic_dec(&global_trace.data[cpu]->disabled); |
2394 | } | |
2395 | } | |
0199c4e6 | 2396 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2397 | local_irq_enable(); |
36dfe925 | 2398 | |
9e01c1b7 | 2399 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2400 | |
2401 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2402 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2403 | |
2404 | return count; | |
36dfe925 IM |
2405 | |
2406 | err_unlock: | |
215368e8 | 2407 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2408 | |
2409 | return err; | |
c7078de1 IM |
2410 | } |
2411 | ||
5e2336a0 | 2412 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2413 | .open = tracing_open_generic, |
2414 | .read = tracing_cpumask_read, | |
2415 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2416 | }; |
2417 | ||
fdb372ed | 2418 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 2419 | { |
d8e83d26 SR |
2420 | struct tracer_opt *trace_opts; |
2421 | u32 tracer_flags; | |
d8e83d26 | 2422 | int i; |
adf9f195 | 2423 | |
d8e83d26 SR |
2424 | mutex_lock(&trace_types_lock); |
2425 | tracer_flags = current_trace->flags->val; | |
2426 | trace_opts = current_trace->flags->opts; | |
2427 | ||
bc0c38d1 SR |
2428 | for (i = 0; trace_options[i]; i++) { |
2429 | if (trace_flags & (1 << i)) | |
fdb372ed | 2430 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 2431 | else |
fdb372ed | 2432 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2433 | } |
2434 | ||
adf9f195 FW |
2435 | for (i = 0; trace_opts[i].name; i++) { |
2436 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 2437 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 2438 | else |
fdb372ed | 2439 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 2440 | } |
d8e83d26 | 2441 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2442 | |
fdb372ed | 2443 | return 0; |
bc0c38d1 | 2444 | } |
bc0c38d1 | 2445 | |
8d18eaaf LZ |
2446 | static int __set_tracer_option(struct tracer *trace, |
2447 | struct tracer_flags *tracer_flags, | |
2448 | struct tracer_opt *opts, int neg) | |
2449 | { | |
2450 | int ret; | |
bc0c38d1 | 2451 | |
8d18eaaf LZ |
2452 | ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); |
2453 | if (ret) | |
2454 | return ret; | |
2455 | ||
2456 | if (neg) | |
2457 | tracer_flags->val &= ~opts->bit; | |
2458 | else | |
2459 | tracer_flags->val |= opts->bit; | |
2460 | return 0; | |
bc0c38d1 SR |
2461 | } |
2462 | ||
adf9f195 FW |
2463 | /* Try to assign a tracer specific option */ |
2464 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2465 | { | |
7770841e | 2466 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 2467 | struct tracer_opt *opts = NULL; |
8d18eaaf | 2468 | int i; |
adf9f195 | 2469 | |
7770841e Z |
2470 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2471 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 2472 | |
8d18eaaf LZ |
2473 | if (strcmp(cmp, opts->name) == 0) |
2474 | return __set_tracer_option(trace, trace->flags, | |
2475 | opts, neg); | |
adf9f195 | 2476 | } |
adf9f195 | 2477 | |
8d18eaaf | 2478 | return -EINVAL; |
adf9f195 FW |
2479 | } |
2480 | ||
af4617bd SR |
2481 | static void set_tracer_flags(unsigned int mask, int enabled) |
2482 | { | |
2483 | /* do nothing if flag is already set */ | |
2484 | if (!!(trace_flags & mask) == !!enabled) | |
2485 | return; | |
2486 | ||
2487 | if (enabled) | |
2488 | trace_flags |= mask; | |
2489 | else | |
2490 | trace_flags &= ~mask; | |
af4617bd SR |
2491 | } |
2492 | ||
bc0c38d1 | 2493 | static ssize_t |
ee6bce52 | 2494 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2495 | size_t cnt, loff_t *ppos) |
2496 | { | |
2497 | char buf[64]; | |
8d18eaaf | 2498 | char *cmp; |
bc0c38d1 | 2499 | int neg = 0; |
adf9f195 | 2500 | int ret; |
bc0c38d1 SR |
2501 | int i; |
2502 | ||
cffae437 SR |
2503 | if (cnt >= sizeof(buf)) |
2504 | return -EINVAL; | |
bc0c38d1 SR |
2505 | |
2506 | if (copy_from_user(&buf, ubuf, cnt)) | |
2507 | return -EFAULT; | |
2508 | ||
2509 | buf[cnt] = 0; | |
8d18eaaf | 2510 | cmp = strstrip(buf); |
bc0c38d1 | 2511 | |
8d18eaaf | 2512 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
2513 | neg = 1; |
2514 | cmp += 2; | |
2515 | } | |
2516 | ||
2517 | for (i = 0; trace_options[i]; i++) { | |
8d18eaaf | 2518 | if (strcmp(cmp, trace_options[i]) == 0) { |
af4617bd | 2519 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2520 | break; |
2521 | } | |
2522 | } | |
adf9f195 FW |
2523 | |
2524 | /* If no option could be set, test the specific tracer options */ | |
2525 | if (!trace_options[i]) { | |
d8e83d26 | 2526 | mutex_lock(&trace_types_lock); |
adf9f195 | 2527 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2528 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2529 | if (ret) |
2530 | return ret; | |
2531 | } | |
bc0c38d1 | 2532 | |
cf8517cf | 2533 | *ppos += cnt; |
bc0c38d1 SR |
2534 | |
2535 | return cnt; | |
2536 | } | |
2537 | ||
fdb372ed LZ |
2538 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
2539 | { | |
2540 | if (tracing_disabled) | |
2541 | return -ENODEV; | |
2542 | return single_open(file, tracing_trace_options_show, NULL); | |
2543 | } | |
2544 | ||
5e2336a0 | 2545 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
2546 | .open = tracing_trace_options_open, |
2547 | .read = seq_read, | |
2548 | .llseek = seq_lseek, | |
2549 | .release = single_release, | |
ee6bce52 | 2550 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
2551 | }; |
2552 | ||
7bd2f24c IM |
2553 | static const char readme_msg[] = |
2554 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2555 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2556 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
bc2b6871 | 2557 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
156f5a78 | 2558 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2559 | "nop\n" |
156f5a78 GL |
2560 | "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" |
2561 | "# cat /sys/kernel/debug/tracing/current_tracer\n" | |
7bd2f24c | 2562 | "sched_switch\n" |
156f5a78 | 2563 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2564 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 GL |
2565 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
2566 | "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
2567 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" | |
2568 | "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
7bd2f24c IM |
2569 | ; |
2570 | ||
2571 | static ssize_t | |
2572 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2573 | size_t cnt, loff_t *ppos) | |
2574 | { | |
2575 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2576 | readme_msg, strlen(readme_msg)); | |
2577 | } | |
2578 | ||
5e2336a0 | 2579 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2580 | .open = tracing_open_generic, |
2581 | .read = tracing_readme_read, | |
7bd2f24c IM |
2582 | }; |
2583 | ||
69abe6a5 AP |
2584 | static ssize_t |
2585 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2586 | size_t cnt, loff_t *ppos) | |
2587 | { | |
2588 | char *buf_comm; | |
2589 | char *file_buf; | |
2590 | char *buf; | |
2591 | int len = 0; | |
2592 | int pid; | |
2593 | int i; | |
2594 | ||
2595 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2596 | if (!file_buf) | |
2597 | return -ENOMEM; | |
2598 | ||
2599 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2600 | if (!buf_comm) { | |
2601 | kfree(file_buf); | |
2602 | return -ENOMEM; | |
2603 | } | |
2604 | ||
2605 | buf = file_buf; | |
2606 | ||
2607 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2608 | int r; | |
2609 | ||
2610 | pid = map_cmdline_to_pid[i]; | |
2611 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2612 | continue; | |
2613 | ||
2614 | trace_find_cmdline(pid, buf_comm); | |
2615 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2616 | buf += r; | |
2617 | len += r; | |
2618 | } | |
2619 | ||
2620 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2621 | file_buf, len); | |
2622 | ||
2623 | kfree(file_buf); | |
2624 | kfree(buf_comm); | |
2625 | ||
2626 | return len; | |
2627 | } | |
2628 | ||
2629 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2630 | .open = tracing_open_generic, | |
2631 | .read = tracing_saved_cmdlines_read, | |
2632 | }; | |
2633 | ||
bc0c38d1 SR |
2634 | static ssize_t |
2635 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2636 | size_t cnt, loff_t *ppos) | |
2637 | { | |
bc0c38d1 SR |
2638 | char buf[64]; |
2639 | int r; | |
2640 | ||
9036990d | 2641 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2642 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2643 | } |
2644 | ||
2645 | static ssize_t | |
2646 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2647 | size_t cnt, loff_t *ppos) | |
2648 | { | |
2649 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2650 | char buf[64]; |
5e39841c | 2651 | unsigned long val; |
c6caeeb1 | 2652 | int ret; |
bc0c38d1 | 2653 | |
cffae437 SR |
2654 | if (cnt >= sizeof(buf)) |
2655 | return -EINVAL; | |
bc0c38d1 SR |
2656 | |
2657 | if (copy_from_user(&buf, ubuf, cnt)) | |
2658 | return -EFAULT; | |
2659 | ||
2660 | buf[cnt] = 0; | |
2661 | ||
c6caeeb1 SR |
2662 | ret = strict_strtoul(buf, 10, &val); |
2663 | if (ret < 0) | |
2664 | return ret; | |
bc0c38d1 SR |
2665 | |
2666 | val = !!val; | |
2667 | ||
2668 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2669 | if (tracer_enabled ^ val) { |
2670 | if (val) { | |
bc0c38d1 | 2671 | tracer_enabled = 1; |
9036990d SR |
2672 | if (current_trace->start) |
2673 | current_trace->start(tr); | |
2674 | tracing_start(); | |
2675 | } else { | |
bc0c38d1 | 2676 | tracer_enabled = 0; |
9036990d SR |
2677 | tracing_stop(); |
2678 | if (current_trace->stop) | |
2679 | current_trace->stop(tr); | |
2680 | } | |
bc0c38d1 SR |
2681 | } |
2682 | mutex_unlock(&trace_types_lock); | |
2683 | ||
cf8517cf | 2684 | *ppos += cnt; |
bc0c38d1 SR |
2685 | |
2686 | return cnt; | |
2687 | } | |
2688 | ||
2689 | static ssize_t | |
2690 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2691 | size_t cnt, loff_t *ppos) | |
2692 | { | |
ee6c2c1b | 2693 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
2694 | int r; |
2695 | ||
2696 | mutex_lock(&trace_types_lock); | |
2697 | if (current_trace) | |
2698 | r = sprintf(buf, "%s\n", current_trace->name); | |
2699 | else | |
2700 | r = sprintf(buf, "\n"); | |
2701 | mutex_unlock(&trace_types_lock); | |
2702 | ||
4bf39a94 | 2703 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2704 | } |
2705 | ||
b6f11df2 ACM |
2706 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2707 | { | |
2708 | tracing_reset_online_cpus(tr); | |
2709 | return t->init(tr); | |
2710 | } | |
2711 | ||
73c5162a SR |
2712 | static int tracing_resize_ring_buffer(unsigned long size) |
2713 | { | |
2714 | int ret; | |
2715 | ||
2716 | /* | |
2717 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2718 | * we use the size that was given, and we can forget about |
2719 | * expanding it later. | |
73c5162a SR |
2720 | */ |
2721 | ring_buffer_expanded = 1; | |
2722 | ||
2723 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2724 | if (ret < 0) | |
2725 | return ret; | |
2726 | ||
2727 | ret = ring_buffer_resize(max_tr.buffer, size); | |
2728 | if (ret < 0) { | |
2729 | int r; | |
2730 | ||
2731 | r = ring_buffer_resize(global_trace.buffer, | |
2732 | global_trace.entries); | |
2733 | if (r < 0) { | |
a123c52b SR |
2734 | /* |
2735 | * AARGH! We are left with different | |
2736 | * size max buffer!!!! | |
2737 | * The max buffer is our "snapshot" buffer. | |
2738 | * When a tracer needs a snapshot (one of the | |
2739 | * latency tracers), it swaps the max buffer | |
2740 | * with the saved snap shot. We succeeded to | |
2741 | * update the size of the main buffer, but failed to | |
2742 | * update the size of the max buffer. But when we tried | |
2743 | * to reset the main buffer to the original size, we | |
2744 | * failed there too. This is very unlikely to | |
2745 | * happen, but if it does, warn and kill all | |
2746 | * tracing. | |
2747 | */ | |
73c5162a SR |
2748 | WARN_ON(1); |
2749 | tracing_disabled = 1; | |
2750 | } | |
2751 | return ret; | |
2752 | } | |
2753 | ||
2754 | global_trace.entries = size; | |
2755 | ||
2756 | return ret; | |
2757 | } | |
2758 | ||
1852fcce SR |
2759 | /** |
2760 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2761 | * | |
2762 | * To save on memory when the tracing is never used on a system with it | |
2763 | * configured in. The ring buffers are set to a minimum size. But once | |
2764 | * a user starts to use the tracing facility, then they need to grow | |
2765 | * to their default size. | |
2766 | * | |
2767 | * This function is to be called when a tracer is about to be used. | |
2768 | */ | |
2769 | int tracing_update_buffers(void) | |
2770 | { | |
2771 | int ret = 0; | |
2772 | ||
1027fcb2 | 2773 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2774 | if (!ring_buffer_expanded) |
2775 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2776 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2777 | |
2778 | return ret; | |
2779 | } | |
2780 | ||
577b785f SR |
2781 | struct trace_option_dentry; |
2782 | ||
2783 | static struct trace_option_dentry * | |
2784 | create_trace_option_files(struct tracer *tracer); | |
2785 | ||
2786 | static void | |
2787 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2788 | ||
b2821ae6 | 2789 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2790 | { |
577b785f | 2791 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2792 | struct trace_array *tr = &global_trace; |
2793 | struct tracer *t; | |
d9e54076 | 2794 | int ret = 0; |
bc0c38d1 | 2795 | |
1027fcb2 SR |
2796 | mutex_lock(&trace_types_lock); |
2797 | ||
73c5162a SR |
2798 | if (!ring_buffer_expanded) { |
2799 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2800 | if (ret < 0) | |
59f586db | 2801 | goto out; |
73c5162a SR |
2802 | ret = 0; |
2803 | } | |
2804 | ||
bc0c38d1 SR |
2805 | for (t = trace_types; t; t = t->next) { |
2806 | if (strcmp(t->name, buf) == 0) | |
2807 | break; | |
2808 | } | |
c2931e05 FW |
2809 | if (!t) { |
2810 | ret = -EINVAL; | |
2811 | goto out; | |
2812 | } | |
2813 | if (t == current_trace) | |
bc0c38d1 SR |
2814 | goto out; |
2815 | ||
9f029e83 | 2816 | trace_branch_disable(); |
bc0c38d1 SR |
2817 | if (current_trace && current_trace->reset) |
2818 | current_trace->reset(tr); | |
2819 | ||
577b785f SR |
2820 | destroy_trace_option_files(topts); |
2821 | ||
bc0c38d1 | 2822 | current_trace = t; |
577b785f SR |
2823 | |
2824 | topts = create_trace_option_files(current_trace); | |
2825 | ||
1c80025a | 2826 | if (t->init) { |
b6f11df2 | 2827 | ret = tracer_init(t, tr); |
1c80025a FW |
2828 | if (ret) |
2829 | goto out; | |
2830 | } | |
bc0c38d1 | 2831 | |
9f029e83 | 2832 | trace_branch_enable(tr); |
bc0c38d1 SR |
2833 | out: |
2834 | mutex_unlock(&trace_types_lock); | |
2835 | ||
d9e54076 PZ |
2836 | return ret; |
2837 | } | |
2838 | ||
2839 | static ssize_t | |
2840 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2841 | size_t cnt, loff_t *ppos) | |
2842 | { | |
ee6c2c1b | 2843 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
2844 | int i; |
2845 | size_t ret; | |
e6e7a65a FW |
2846 | int err; |
2847 | ||
2848 | ret = cnt; | |
d9e54076 | 2849 | |
ee6c2c1b LZ |
2850 | if (cnt > MAX_TRACER_SIZE) |
2851 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
2852 | |
2853 | if (copy_from_user(&buf, ubuf, cnt)) | |
2854 | return -EFAULT; | |
2855 | ||
2856 | buf[cnt] = 0; | |
2857 | ||
2858 | /* strip ending whitespace. */ | |
2859 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2860 | buf[i] = 0; | |
2861 | ||
e6e7a65a FW |
2862 | err = tracing_set_tracer(buf); |
2863 | if (err) | |
2864 | return err; | |
d9e54076 | 2865 | |
cf8517cf | 2866 | *ppos += ret; |
bc0c38d1 | 2867 | |
c2931e05 | 2868 | return ret; |
bc0c38d1 SR |
2869 | } |
2870 | ||
2871 | static ssize_t | |
2872 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2873 | size_t cnt, loff_t *ppos) | |
2874 | { | |
2875 | unsigned long *ptr = filp->private_data; | |
2876 | char buf[64]; | |
2877 | int r; | |
2878 | ||
cffae437 | 2879 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2880 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2881 | if (r > sizeof(buf)) |
2882 | r = sizeof(buf); | |
4bf39a94 | 2883 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2884 | } |
2885 | ||
2886 | static ssize_t | |
2887 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2888 | size_t cnt, loff_t *ppos) | |
2889 | { | |
5e39841c | 2890 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2891 | char buf[64]; |
5e39841c | 2892 | unsigned long val; |
c6caeeb1 | 2893 | int ret; |
bc0c38d1 | 2894 | |
cffae437 SR |
2895 | if (cnt >= sizeof(buf)) |
2896 | return -EINVAL; | |
bc0c38d1 SR |
2897 | |
2898 | if (copy_from_user(&buf, ubuf, cnt)) | |
2899 | return -EFAULT; | |
2900 | ||
2901 | buf[cnt] = 0; | |
2902 | ||
c6caeeb1 SR |
2903 | ret = strict_strtoul(buf, 10, &val); |
2904 | if (ret < 0) | |
2905 | return ret; | |
bc0c38d1 SR |
2906 | |
2907 | *ptr = val * 1000; | |
2908 | ||
2909 | return cnt; | |
2910 | } | |
2911 | ||
b3806b43 SR |
2912 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2913 | { | |
b04cc6b1 | 2914 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2915 | struct trace_iterator *iter; |
b04cc6b1 | 2916 | int ret = 0; |
b3806b43 SR |
2917 | |
2918 | if (tracing_disabled) | |
2919 | return -ENODEV; | |
2920 | ||
b04cc6b1 FW |
2921 | mutex_lock(&trace_types_lock); |
2922 | ||
b3806b43 SR |
2923 | /* create a buffer to store the information to pass to userspace */ |
2924 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2925 | if (!iter) { |
2926 | ret = -ENOMEM; | |
2927 | goto out; | |
2928 | } | |
b3806b43 | 2929 | |
d7350c3f FW |
2930 | /* |
2931 | * We make a copy of the current tracer to avoid concurrent | |
2932 | * changes on it while we are reading. | |
2933 | */ | |
2934 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
2935 | if (!iter->trace) { | |
2936 | ret = -ENOMEM; | |
2937 | goto fail; | |
2938 | } | |
2939 | if (current_trace) | |
2940 | *iter->trace = *current_trace; | |
2941 | ||
4462344e | 2942 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 2943 | ret = -ENOMEM; |
d7350c3f | 2944 | goto fail; |
4462344e RR |
2945 | } |
2946 | ||
a309720c | 2947 | /* trace pipe does not show start of buffer */ |
4462344e | 2948 | cpumask_setall(iter->started); |
a309720c | 2949 | |
112f38a7 SR |
2950 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
2951 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2952 | ||
b04cc6b1 | 2953 | iter->cpu_file = cpu_file; |
b3806b43 | 2954 | iter->tr = &global_trace; |
d7350c3f | 2955 | mutex_init(&iter->mutex); |
b3806b43 SR |
2956 | filp->private_data = iter; |
2957 | ||
107bad8b SR |
2958 | if (iter->trace->pipe_open) |
2959 | iter->trace->pipe_open(iter); | |
107bad8b | 2960 | |
b04cc6b1 FW |
2961 | out: |
2962 | mutex_unlock(&trace_types_lock); | |
2963 | return ret; | |
d7350c3f FW |
2964 | |
2965 | fail: | |
2966 | kfree(iter->trace); | |
2967 | kfree(iter); | |
2968 | mutex_unlock(&trace_types_lock); | |
2969 | return ret; | |
b3806b43 SR |
2970 | } |
2971 | ||
2972 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2973 | { | |
2974 | struct trace_iterator *iter = file->private_data; | |
2975 | ||
b04cc6b1 FW |
2976 | mutex_lock(&trace_types_lock); |
2977 | ||
29bf4a5e | 2978 | if (iter->trace->pipe_close) |
c521efd1 SR |
2979 | iter->trace->pipe_close(iter); |
2980 | ||
b04cc6b1 FW |
2981 | mutex_unlock(&trace_types_lock); |
2982 | ||
4462344e | 2983 | free_cpumask_var(iter->started); |
d7350c3f FW |
2984 | mutex_destroy(&iter->mutex); |
2985 | kfree(iter->trace); | |
b3806b43 | 2986 | kfree(iter); |
b3806b43 SR |
2987 | |
2988 | return 0; | |
2989 | } | |
2990 | ||
2a2cc8f7 SSP |
2991 | static unsigned int |
2992 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2993 | { | |
2994 | struct trace_iterator *iter = filp->private_data; | |
2995 | ||
2996 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2997 | /* | |
2998 | * Always select as readable when in blocking mode | |
2999 | */ | |
3000 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 3001 | } else { |
2a2cc8f7 SSP |
3002 | if (!trace_empty(iter)) |
3003 | return POLLIN | POLLRDNORM; | |
3004 | poll_wait(filp, &trace_wait, poll_table); | |
3005 | if (!trace_empty(iter)) | |
3006 | return POLLIN | POLLRDNORM; | |
3007 | ||
3008 | return 0; | |
3009 | } | |
3010 | } | |
3011 | ||
6eaaa5d5 FW |
3012 | |
3013 | void default_wait_pipe(struct trace_iterator *iter) | |
3014 | { | |
3015 | DEFINE_WAIT(wait); | |
3016 | ||
3017 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
3018 | ||
3019 | if (trace_empty(iter)) | |
3020 | schedule(); | |
3021 | ||
3022 | finish_wait(&trace_wait, &wait); | |
3023 | } | |
3024 | ||
3025 | /* | |
3026 | * This is a make-shift waitqueue. | |
3027 | * A tracer might use this callback on some rare cases: | |
3028 | * | |
3029 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
3030 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
3031 | * 2) the function tracers, trace all functions, we don't want | |
3032 | * the overhead of calling wake_up and friends | |
3033 | * (and tracing them too) | |
3034 | * | |
3035 | * Anyway, this is really very primitive wakeup. | |
3036 | */ | |
3037 | void poll_wait_pipe(struct trace_iterator *iter) | |
3038 | { | |
3039 | set_current_state(TASK_INTERRUPTIBLE); | |
3040 | /* sleep for 100 msecs, and try again. */ | |
3041 | schedule_timeout(HZ / 10); | |
3042 | } | |
3043 | ||
ff98781b EGM |
3044 | /* Must be called with trace_types_lock mutex held. */ |
3045 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
3046 | { |
3047 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 3048 | |
b3806b43 | 3049 | while (trace_empty(iter)) { |
2dc8f095 | 3050 | |
107bad8b | 3051 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 3052 | return -EAGAIN; |
107bad8b | 3053 | } |
2dc8f095 | 3054 | |
d7350c3f | 3055 | mutex_unlock(&iter->mutex); |
107bad8b | 3056 | |
6eaaa5d5 | 3057 | iter->trace->wait_pipe(iter); |
b3806b43 | 3058 | |
d7350c3f | 3059 | mutex_lock(&iter->mutex); |
107bad8b | 3060 | |
6eaaa5d5 | 3061 | if (signal_pending(current)) |
ff98781b | 3062 | return -EINTR; |
b3806b43 SR |
3063 | |
3064 | /* | |
3065 | * We block until we read something and tracing is disabled. | |
3066 | * We still block if tracing is disabled, but we have never | |
3067 | * read anything. This allows a user to cat this file, and | |
3068 | * then enable tracing. But after we have read something, | |
3069 | * we give an EOF when tracing is again disabled. | |
3070 | * | |
3071 | * iter->pos will be 0 if we haven't read anything. | |
3072 | */ | |
3073 | if (!tracer_enabled && iter->pos) | |
3074 | break; | |
b3806b43 SR |
3075 | } |
3076 | ||
ff98781b EGM |
3077 | return 1; |
3078 | } | |
3079 | ||
3080 | /* | |
3081 | * Consumer reader. | |
3082 | */ | |
3083 | static ssize_t | |
3084 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
3085 | size_t cnt, loff_t *ppos) | |
3086 | { | |
3087 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 3088 | static struct tracer *old_tracer; |
ff98781b EGM |
3089 | ssize_t sret; |
3090 | ||
3091 | /* return any leftover data */ | |
3092 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
3093 | if (sret != -EBUSY) | |
3094 | return sret; | |
3095 | ||
f9520750 | 3096 | trace_seq_init(&iter->seq); |
ff98781b | 3097 | |
d7350c3f | 3098 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 3099 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3100 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3101 | old_tracer = current_trace; | |
3102 | *iter->trace = *current_trace; | |
3103 | } | |
3104 | mutex_unlock(&trace_types_lock); | |
3105 | ||
3106 | /* | |
3107 | * Avoid more than one consumer on a single file descriptor | |
3108 | * This is just a matter of traces coherency, the ring buffer itself | |
3109 | * is protected. | |
3110 | */ | |
3111 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
3112 | if (iter->trace->read) { |
3113 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
3114 | if (sret) | |
3115 | goto out; | |
3116 | } | |
3117 | ||
3118 | waitagain: | |
3119 | sret = tracing_wait_pipe(filp); | |
3120 | if (sret <= 0) | |
3121 | goto out; | |
3122 | ||
b3806b43 | 3123 | /* stop when tracing is finished */ |
ff98781b EGM |
3124 | if (trace_empty(iter)) { |
3125 | sret = 0; | |
107bad8b | 3126 | goto out; |
ff98781b | 3127 | } |
b3806b43 SR |
3128 | |
3129 | if (cnt >= PAGE_SIZE) | |
3130 | cnt = PAGE_SIZE - 1; | |
3131 | ||
53d0aa77 | 3132 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
3133 | memset(&iter->seq, 0, |
3134 | sizeof(struct trace_iterator) - | |
3135 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 3136 | iter->pos = -1; |
b3806b43 | 3137 | |
4f535968 | 3138 | trace_event_read_lock(); |
7e53bd42 | 3139 | trace_access_lock(iter->cpu_file); |
088b1e42 | 3140 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 3141 | enum print_line_t ret; |
088b1e42 SR |
3142 | int len = iter->seq.len; |
3143 | ||
f9896bf3 | 3144 | ret = print_trace_line(iter); |
2c4f035f | 3145 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
3146 | /* don't print partial lines */ |
3147 | iter->seq.len = len; | |
b3806b43 | 3148 | break; |
088b1e42 | 3149 | } |
b91facc3 FW |
3150 | if (ret != TRACE_TYPE_NO_CONSUME) |
3151 | trace_consume(iter); | |
b3806b43 SR |
3152 | |
3153 | if (iter->seq.len >= cnt) | |
3154 | break; | |
b3806b43 | 3155 | } |
7e53bd42 | 3156 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3157 | trace_event_read_unlock(); |
b3806b43 | 3158 | |
b3806b43 | 3159 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3160 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3161 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3162 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3163 | |
3164 | /* | |
3165 | * If there was nothing to send to user, inspite of consuming trace | |
3166 | * entries, go back to wait for more entries. | |
3167 | */ | |
6c6c2796 | 3168 | if (sret == -EBUSY) |
9ff4b974 | 3169 | goto waitagain; |
b3806b43 | 3170 | |
107bad8b | 3171 | out: |
d7350c3f | 3172 | mutex_unlock(&iter->mutex); |
107bad8b | 3173 | |
6c6c2796 | 3174 | return sret; |
b3806b43 SR |
3175 | } |
3176 | ||
3c56819b EGM |
3177 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3178 | struct pipe_buffer *buf) | |
3179 | { | |
3180 | __free_page(buf->page); | |
3181 | } | |
3182 | ||
3183 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3184 | unsigned int idx) | |
3185 | { | |
3186 | __free_page(spd->pages[idx]); | |
3187 | } | |
3188 | ||
28dfef8f | 3189 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
3190 | .can_merge = 0, |
3191 | .map = generic_pipe_buf_map, | |
3192 | .unmap = generic_pipe_buf_unmap, | |
3193 | .confirm = generic_pipe_buf_confirm, | |
3194 | .release = tracing_pipe_buf_release, | |
3195 | .steal = generic_pipe_buf_steal, | |
3196 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3197 | }; |
3198 | ||
34cd4998 | 3199 | static size_t |
fa7c7f6e | 3200 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3201 | { |
3202 | size_t count; | |
3203 | int ret; | |
3204 | ||
3205 | /* Seq buffer is page-sized, exactly what we need. */ | |
3206 | for (;;) { | |
3207 | count = iter->seq.len; | |
3208 | ret = print_trace_line(iter); | |
3209 | count = iter->seq.len - count; | |
3210 | if (rem < count) { | |
3211 | rem = 0; | |
3212 | iter->seq.len -= count; | |
3213 | break; | |
3214 | } | |
3215 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3216 | iter->seq.len -= count; | |
3217 | break; | |
3218 | } | |
3219 | ||
74e7ff8c LJ |
3220 | if (ret != TRACE_TYPE_NO_CONSUME) |
3221 | trace_consume(iter); | |
34cd4998 SR |
3222 | rem -= count; |
3223 | if (!find_next_entry_inc(iter)) { | |
3224 | rem = 0; | |
3225 | iter->ent = NULL; | |
3226 | break; | |
3227 | } | |
3228 | } | |
3229 | ||
3230 | return rem; | |
3231 | } | |
3232 | ||
3c56819b EGM |
3233 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3234 | loff_t *ppos, | |
3235 | struct pipe_inode_info *pipe, | |
3236 | size_t len, | |
3237 | unsigned int flags) | |
3238 | { | |
3239 | struct page *pages[PIPE_BUFFERS]; | |
3240 | struct partial_page partial[PIPE_BUFFERS]; | |
3241 | struct trace_iterator *iter = filp->private_data; | |
3242 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
3243 | .pages = pages, |
3244 | .partial = partial, | |
3245 | .nr_pages = 0, /* This gets updated below. */ | |
3246 | .flags = flags, | |
3247 | .ops = &tracing_pipe_buf_ops, | |
3248 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3249 | }; |
d7350c3f | 3250 | static struct tracer *old_tracer; |
3c56819b | 3251 | ssize_t ret; |
34cd4998 | 3252 | size_t rem; |
3c56819b EGM |
3253 | unsigned int i; |
3254 | ||
d7350c3f | 3255 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3256 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3257 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3258 | old_tracer = current_trace; | |
3259 | *iter->trace = *current_trace; | |
3260 | } | |
3261 | mutex_unlock(&trace_types_lock); | |
3262 | ||
3263 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3264 | |
3265 | if (iter->trace->splice_read) { | |
3266 | ret = iter->trace->splice_read(iter, filp, | |
3267 | ppos, pipe, len, flags); | |
3268 | if (ret) | |
34cd4998 | 3269 | goto out_err; |
3c56819b EGM |
3270 | } |
3271 | ||
3272 | ret = tracing_wait_pipe(filp); | |
3273 | if (ret <= 0) | |
34cd4998 | 3274 | goto out_err; |
3c56819b EGM |
3275 | |
3276 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
3277 | ret = -EFAULT; | |
34cd4998 | 3278 | goto out_err; |
3c56819b EGM |
3279 | } |
3280 | ||
4f535968 | 3281 | trace_event_read_lock(); |
7e53bd42 | 3282 | trace_access_lock(iter->cpu_file); |
4f535968 | 3283 | |
3c56819b EGM |
3284 | /* Fill as many pages as possible. */ |
3285 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
3286 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
3287 | if (!pages[i]) |
3288 | break; | |
3c56819b | 3289 | |
fa7c7f6e | 3290 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3291 | |
3292 | /* Copy the data into the page, so we can start over. */ | |
3293 | ret = trace_seq_to_buffer(&iter->seq, | |
3294 | page_address(pages[i]), | |
3295 | iter->seq.len); | |
3296 | if (ret < 0) { | |
3297 | __free_page(pages[i]); | |
3298 | break; | |
3299 | } | |
3300 | partial[i].offset = 0; | |
3301 | partial[i].len = iter->seq.len; | |
3302 | ||
f9520750 | 3303 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3304 | } |
3305 | ||
7e53bd42 | 3306 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3307 | trace_event_read_unlock(); |
d7350c3f | 3308 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3309 | |
3310 | spd.nr_pages = i; | |
3311 | ||
3312 | return splice_to_pipe(pipe, &spd); | |
3313 | ||
34cd4998 | 3314 | out_err: |
d7350c3f | 3315 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3316 | |
3317 | return ret; | |
3318 | } | |
3319 | ||
a98a3c3f SR |
3320 | static ssize_t |
3321 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3322 | size_t cnt, loff_t *ppos) | |
3323 | { | |
3324 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3325 | char buf[96]; |
a98a3c3f SR |
3326 | int r; |
3327 | ||
db526ca3 SR |
3328 | mutex_lock(&trace_types_lock); |
3329 | if (!ring_buffer_expanded) | |
3330 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3331 | tr->entries >> 10, | |
3332 | trace_buf_size >> 10); | |
3333 | else | |
3334 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3335 | mutex_unlock(&trace_types_lock); | |
3336 | ||
a98a3c3f SR |
3337 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3338 | } | |
3339 | ||
3340 | static ssize_t | |
3341 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3342 | size_t cnt, loff_t *ppos) | |
3343 | { | |
3344 | unsigned long val; | |
3345 | char buf[64]; | |
bf5e6519 | 3346 | int ret, cpu; |
a98a3c3f | 3347 | |
cffae437 SR |
3348 | if (cnt >= sizeof(buf)) |
3349 | return -EINVAL; | |
a98a3c3f SR |
3350 | |
3351 | if (copy_from_user(&buf, ubuf, cnt)) | |
3352 | return -EFAULT; | |
3353 | ||
3354 | buf[cnt] = 0; | |
3355 | ||
c6caeeb1 SR |
3356 | ret = strict_strtoul(buf, 10, &val); |
3357 | if (ret < 0) | |
3358 | return ret; | |
a98a3c3f SR |
3359 | |
3360 | /* must have at least 1 entry */ | |
3361 | if (!val) | |
3362 | return -EINVAL; | |
3363 | ||
3364 | mutex_lock(&trace_types_lock); | |
3365 | ||
c76f0694 | 3366 | tracing_stop(); |
a98a3c3f | 3367 | |
bf5e6519 SR |
3368 | /* disable all cpu buffers */ |
3369 | for_each_tracing_cpu(cpu) { | |
3370 | if (global_trace.data[cpu]) | |
3371 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3372 | if (max_tr.data[cpu]) | |
3373 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3374 | } | |
3375 | ||
1696b2b0 SR |
3376 | /* value is in KB */ |
3377 | val <<= 10; | |
3378 | ||
3928a8a2 | 3379 | if (val != global_trace.entries) { |
73c5162a | 3380 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3381 | if (ret < 0) { |
3382 | cnt = ret; | |
3eefae99 SR |
3383 | goto out; |
3384 | } | |
a98a3c3f SR |
3385 | } |
3386 | ||
cf8517cf | 3387 | *ppos += cnt; |
a98a3c3f | 3388 | |
19384c03 SR |
3389 | /* If check pages failed, return ENOMEM */ |
3390 | if (tracing_disabled) | |
3391 | cnt = -ENOMEM; | |
a98a3c3f | 3392 | out: |
bf5e6519 SR |
3393 | for_each_tracing_cpu(cpu) { |
3394 | if (global_trace.data[cpu]) | |
3395 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3396 | if (max_tr.data[cpu]) | |
3397 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3398 | } | |
3399 | ||
c76f0694 | 3400 | tracing_start(); |
a98a3c3f SR |
3401 | max_tr.entries = global_trace.entries; |
3402 | mutex_unlock(&trace_types_lock); | |
3403 | ||
3404 | return cnt; | |
3405 | } | |
3406 | ||
f2942487 CE |
3407 | static int mark_printk(const char *fmt, ...) |
3408 | { | |
3409 | int ret; | |
3410 | va_list args; | |
3411 | va_start(args, fmt); | |
3412 | ret = trace_vprintk(0, fmt, args); | |
3413 | va_end(args); | |
3414 | return ret; | |
3415 | } | |
3416 | ||
5bf9a1ee PP |
3417 | static ssize_t |
3418 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3419 | size_t cnt, loff_t *fpos) | |
3420 | { | |
3421 | char *buf; | |
5bf9a1ee | 3422 | |
c76f0694 | 3423 | if (tracing_disabled) |
5bf9a1ee PP |
3424 | return -EINVAL; |
3425 | ||
3426 | if (cnt > TRACE_BUF_SIZE) | |
3427 | cnt = TRACE_BUF_SIZE; | |
3428 | ||
c13d2f7c | 3429 | buf = kmalloc(cnt + 2, GFP_KERNEL); |
5bf9a1ee PP |
3430 | if (buf == NULL) |
3431 | return -ENOMEM; | |
3432 | ||
3433 | if (copy_from_user(buf, ubuf, cnt)) { | |
3434 | kfree(buf); | |
3435 | return -EFAULT; | |
3436 | } | |
c13d2f7c CE |
3437 | if (buf[cnt-1] != '\n') { |
3438 | buf[cnt] = '\n'; | |
3439 | buf[cnt+1] = '\0'; | |
3440 | } else | |
3441 | buf[cnt] = '\0'; | |
5bf9a1ee | 3442 | |
f2942487 | 3443 | cnt = mark_printk("%s", buf); |
5bf9a1ee PP |
3444 | kfree(buf); |
3445 | *fpos += cnt; | |
3446 | ||
3447 | return cnt; | |
3448 | } | |
3449 | ||
13f16d20 | 3450 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 3451 | { |
5079f326 Z |
3452 | int i; |
3453 | ||
3454 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 3455 | seq_printf(m, |
5079f326 Z |
3456 | "%s%s%s%s", i ? " " : "", |
3457 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3458 | i == trace_clock_id ? "]" : ""); | |
13f16d20 | 3459 | seq_putc(m, '\n'); |
5079f326 | 3460 | |
13f16d20 | 3461 | return 0; |
5079f326 Z |
3462 | } |
3463 | ||
3464 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
3465 | size_t cnt, loff_t *fpos) | |
3466 | { | |
3467 | char buf[64]; | |
3468 | const char *clockstr; | |
3469 | int i; | |
3470 | ||
3471 | if (cnt >= sizeof(buf)) | |
3472 | return -EINVAL; | |
3473 | ||
3474 | if (copy_from_user(&buf, ubuf, cnt)) | |
3475 | return -EFAULT; | |
3476 | ||
3477 | buf[cnt] = 0; | |
3478 | ||
3479 | clockstr = strstrip(buf); | |
3480 | ||
3481 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
3482 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
3483 | break; | |
3484 | } | |
3485 | if (i == ARRAY_SIZE(trace_clocks)) | |
3486 | return -EINVAL; | |
3487 | ||
3488 | trace_clock_id = i; | |
3489 | ||
3490 | mutex_lock(&trace_types_lock); | |
3491 | ||
3492 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
3493 | if (max_tr.buffer) | |
3494 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
3495 | ||
3496 | mutex_unlock(&trace_types_lock); | |
3497 | ||
3498 | *fpos += cnt; | |
3499 | ||
3500 | return cnt; | |
3501 | } | |
3502 | ||
13f16d20 LZ |
3503 | static int tracing_clock_open(struct inode *inode, struct file *file) |
3504 | { | |
3505 | if (tracing_disabled) | |
3506 | return -ENODEV; | |
3507 | return single_open(file, tracing_clock_show, NULL); | |
3508 | } | |
3509 | ||
5e2336a0 | 3510 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3511 | .open = tracing_open_generic, |
3512 | .read = tracing_max_lat_read, | |
3513 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
3514 | }; |
3515 | ||
5e2336a0 | 3516 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3517 | .open = tracing_open_generic, |
3518 | .read = tracing_ctrl_read, | |
3519 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
3520 | }; |
3521 | ||
5e2336a0 | 3522 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3523 | .open = tracing_open_generic, |
3524 | .read = tracing_set_trace_read, | |
3525 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
3526 | }; |
3527 | ||
5e2336a0 | 3528 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3529 | .open = tracing_open_pipe, |
2a2cc8f7 | 3530 | .poll = tracing_poll_pipe, |
4bf39a94 | 3531 | .read = tracing_read_pipe, |
3c56819b | 3532 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3533 | .release = tracing_release_pipe, |
b3806b43 SR |
3534 | }; |
3535 | ||
5e2336a0 | 3536 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3537 | .open = tracing_open_generic, |
3538 | .read = tracing_entries_read, | |
3539 | .write = tracing_entries_write, | |
3540 | }; | |
3541 | ||
5e2336a0 | 3542 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3543 | .open = tracing_open_generic, |
5bf9a1ee PP |
3544 | .write = tracing_mark_write, |
3545 | }; | |
3546 | ||
5079f326 | 3547 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
3548 | .open = tracing_clock_open, |
3549 | .read = seq_read, | |
3550 | .llseek = seq_lseek, | |
3551 | .release = single_release, | |
5079f326 Z |
3552 | .write = tracing_clock_write, |
3553 | }; | |
3554 | ||
2cadf913 SR |
3555 | struct ftrace_buffer_info { |
3556 | struct trace_array *tr; | |
3557 | void *spare; | |
3558 | int cpu; | |
3559 | unsigned int read; | |
3560 | }; | |
3561 | ||
3562 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3563 | { | |
3564 | int cpu = (int)(long)inode->i_private; | |
3565 | struct ftrace_buffer_info *info; | |
3566 | ||
3567 | if (tracing_disabled) | |
3568 | return -ENODEV; | |
3569 | ||
3570 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3571 | if (!info) | |
3572 | return -ENOMEM; | |
3573 | ||
3574 | info->tr = &global_trace; | |
3575 | info->cpu = cpu; | |
ddd538f3 | 3576 | info->spare = NULL; |
2cadf913 SR |
3577 | /* Force reading ring buffer for first read */ |
3578 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3579 | |
3580 | filp->private_data = info; | |
3581 | ||
d1e7e02f | 3582 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3583 | } |
3584 | ||
3585 | static ssize_t | |
3586 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3587 | size_t count, loff_t *ppos) | |
3588 | { | |
3589 | struct ftrace_buffer_info *info = filp->private_data; | |
3590 | unsigned int pos; | |
3591 | ssize_t ret; | |
3592 | size_t size; | |
3593 | ||
2dc5d12b SR |
3594 | if (!count) |
3595 | return 0; | |
3596 | ||
ddd538f3 LJ |
3597 | if (!info->spare) |
3598 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3599 | if (!info->spare) | |
3600 | return -ENOMEM; | |
3601 | ||
2cadf913 SR |
3602 | /* Do we have previous read data to read? */ |
3603 | if (info->read < PAGE_SIZE) | |
3604 | goto read; | |
3605 | ||
3606 | info->read = 0; | |
3607 | ||
7e53bd42 | 3608 | trace_access_lock(info->cpu); |
2cadf913 SR |
3609 | ret = ring_buffer_read_page(info->tr->buffer, |
3610 | &info->spare, | |
3611 | count, | |
3612 | info->cpu, 0); | |
7e53bd42 | 3613 | trace_access_unlock(info->cpu); |
2cadf913 SR |
3614 | if (ret < 0) |
3615 | return 0; | |
3616 | ||
3617 | pos = ring_buffer_page_len(info->spare); | |
3618 | ||
3619 | if (pos < PAGE_SIZE) | |
3620 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3621 | ||
3622 | read: | |
3623 | size = PAGE_SIZE - info->read; | |
3624 | if (size > count) | |
3625 | size = count; | |
3626 | ||
3627 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3628 | if (ret == size) |
2cadf913 | 3629 | return -EFAULT; |
2dc5d12b SR |
3630 | size -= ret; |
3631 | ||
2cadf913 SR |
3632 | *ppos += size; |
3633 | info->read += size; | |
3634 | ||
3635 | return size; | |
3636 | } | |
3637 | ||
3638 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3639 | { | |
3640 | struct ftrace_buffer_info *info = file->private_data; | |
3641 | ||
ddd538f3 LJ |
3642 | if (info->spare) |
3643 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3644 | kfree(info); |
3645 | ||
3646 | return 0; | |
3647 | } | |
3648 | ||
3649 | struct buffer_ref { | |
3650 | struct ring_buffer *buffer; | |
3651 | void *page; | |
3652 | int ref; | |
3653 | }; | |
3654 | ||
3655 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3656 | struct pipe_buffer *buf) | |
3657 | { | |
3658 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3659 | ||
3660 | if (--ref->ref) | |
3661 | return; | |
3662 | ||
3663 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3664 | kfree(ref); | |
3665 | buf->private = 0; | |
3666 | } | |
3667 | ||
3668 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3669 | struct pipe_buffer *buf) | |
3670 | { | |
3671 | return 1; | |
3672 | } | |
3673 | ||
3674 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3675 | struct pipe_buffer *buf) | |
3676 | { | |
3677 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3678 | ||
3679 | ref->ref++; | |
3680 | } | |
3681 | ||
3682 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 3683 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
3684 | .can_merge = 0, |
3685 | .map = generic_pipe_buf_map, | |
3686 | .unmap = generic_pipe_buf_unmap, | |
3687 | .confirm = generic_pipe_buf_confirm, | |
3688 | .release = buffer_pipe_buf_release, | |
3689 | .steal = buffer_pipe_buf_steal, | |
3690 | .get = buffer_pipe_buf_get, | |
3691 | }; | |
3692 | ||
3693 | /* | |
3694 | * Callback from splice_to_pipe(), if we need to release some pages | |
3695 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3696 | */ | |
3697 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3698 | { | |
3699 | struct buffer_ref *ref = | |
3700 | (struct buffer_ref *)spd->partial[i].private; | |
3701 | ||
3702 | if (--ref->ref) | |
3703 | return; | |
3704 | ||
3705 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3706 | kfree(ref); | |
3707 | spd->partial[i].private = 0; | |
3708 | } | |
3709 | ||
3710 | static ssize_t | |
3711 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3712 | struct pipe_inode_info *pipe, size_t len, | |
3713 | unsigned int flags) | |
3714 | { | |
3715 | struct ftrace_buffer_info *info = file->private_data; | |
3716 | struct partial_page partial[PIPE_BUFFERS]; | |
3717 | struct page *pages[PIPE_BUFFERS]; | |
3718 | struct splice_pipe_desc spd = { | |
3719 | .pages = pages, | |
3720 | .partial = partial, | |
3721 | .flags = flags, | |
3722 | .ops = &buffer_pipe_buf_ops, | |
3723 | .spd_release = buffer_spd_release, | |
3724 | }; | |
3725 | struct buffer_ref *ref; | |
93459c6c | 3726 | int entries, size, i; |
2cadf913 SR |
3727 | size_t ret; |
3728 | ||
93cfb3c9 LJ |
3729 | if (*ppos & (PAGE_SIZE - 1)) { |
3730 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
3731 | return -EINVAL; | |
3732 | } | |
3733 | ||
3734 | if (len & (PAGE_SIZE - 1)) { | |
3735 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
3736 | if (len < PAGE_SIZE) | |
3737 | return -EINVAL; | |
3738 | len &= PAGE_MASK; | |
3739 | } | |
3740 | ||
7e53bd42 | 3741 | trace_access_lock(info->cpu); |
93459c6c SR |
3742 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
3743 | ||
3744 | for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) { | |
2cadf913 SR |
3745 | struct page *page; |
3746 | int r; | |
3747 | ||
3748 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3749 | if (!ref) | |
3750 | break; | |
3751 | ||
7267fa68 | 3752 | ref->ref = 1; |
2cadf913 SR |
3753 | ref->buffer = info->tr->buffer; |
3754 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3755 | if (!ref->page) { | |
3756 | kfree(ref); | |
3757 | break; | |
3758 | } | |
3759 | ||
3760 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 3761 | len, info->cpu, 1); |
2cadf913 SR |
3762 | if (r < 0) { |
3763 | ring_buffer_free_read_page(ref->buffer, | |
3764 | ref->page); | |
3765 | kfree(ref); | |
3766 | break; | |
3767 | } | |
3768 | ||
3769 | /* | |
3770 | * zero out any left over data, this is going to | |
3771 | * user land. | |
3772 | */ | |
3773 | size = ring_buffer_page_len(ref->page); | |
3774 | if (size < PAGE_SIZE) | |
3775 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3776 | ||
3777 | page = virt_to_page(ref->page); | |
3778 | ||
3779 | spd.pages[i] = page; | |
3780 | spd.partial[i].len = PAGE_SIZE; | |
3781 | spd.partial[i].offset = 0; | |
3782 | spd.partial[i].private = (unsigned long)ref; | |
3783 | spd.nr_pages++; | |
93cfb3c9 | 3784 | *ppos += PAGE_SIZE; |
93459c6c SR |
3785 | |
3786 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
3787 | } |
3788 | ||
7e53bd42 | 3789 | trace_access_unlock(info->cpu); |
2cadf913 SR |
3790 | spd.nr_pages = i; |
3791 | ||
3792 | /* did we read anything? */ | |
3793 | if (!spd.nr_pages) { | |
3794 | if (flags & SPLICE_F_NONBLOCK) | |
3795 | ret = -EAGAIN; | |
3796 | else | |
3797 | ret = 0; | |
3798 | /* TODO: block */ | |
3799 | return ret; | |
3800 | } | |
3801 | ||
3802 | ret = splice_to_pipe(pipe, &spd); | |
3803 | ||
3804 | return ret; | |
3805 | } | |
3806 | ||
3807 | static const struct file_operations tracing_buffers_fops = { | |
3808 | .open = tracing_buffers_open, | |
3809 | .read = tracing_buffers_read, | |
3810 | .release = tracing_buffers_release, | |
3811 | .splice_read = tracing_buffers_splice_read, | |
3812 | .llseek = no_llseek, | |
3813 | }; | |
3814 | ||
c8d77183 SR |
3815 | static ssize_t |
3816 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
3817 | size_t count, loff_t *ppos) | |
3818 | { | |
3819 | unsigned long cpu = (unsigned long)filp->private_data; | |
3820 | struct trace_array *tr = &global_trace; | |
3821 | struct trace_seq *s; | |
3822 | unsigned long cnt; | |
3823 | ||
e4f2d10f | 3824 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 3825 | if (!s) |
a646365c | 3826 | return -ENOMEM; |
c8d77183 SR |
3827 | |
3828 | trace_seq_init(s); | |
3829 | ||
3830 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
3831 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
3832 | ||
3833 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
3834 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
3835 | ||
3836 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
3837 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
3838 | ||
c8d77183 SR |
3839 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
3840 | ||
3841 | kfree(s); | |
3842 | ||
3843 | return count; | |
3844 | } | |
3845 | ||
3846 | static const struct file_operations tracing_stats_fops = { | |
3847 | .open = tracing_open_generic, | |
3848 | .read = tracing_stats_read, | |
3849 | }; | |
3850 | ||
bc0c38d1 SR |
3851 | #ifdef CONFIG_DYNAMIC_FTRACE |
3852 | ||
b807c3d0 SR |
3853 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3854 | { | |
3855 | return 0; | |
3856 | } | |
3857 | ||
bc0c38d1 | 3858 | static ssize_t |
b807c3d0 | 3859 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3860 | size_t cnt, loff_t *ppos) |
3861 | { | |
a26a2a27 SR |
3862 | static char ftrace_dyn_info_buffer[1024]; |
3863 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3864 | unsigned long *p = filp->private_data; |
b807c3d0 | 3865 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3866 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3867 | int r; |
3868 | ||
b807c3d0 SR |
3869 | mutex_lock(&dyn_info_mutex); |
3870 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3871 | |
a26a2a27 | 3872 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3873 | buf[r++] = '\n'; |
3874 | ||
3875 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3876 | ||
3877 | mutex_unlock(&dyn_info_mutex); | |
3878 | ||
3879 | return r; | |
bc0c38d1 SR |
3880 | } |
3881 | ||
5e2336a0 | 3882 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3883 | .open = tracing_open_generic, |
b807c3d0 | 3884 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3885 | }; |
3886 | #endif | |
3887 | ||
3888 | static struct dentry *d_tracer; | |
3889 | ||
3890 | struct dentry *tracing_init_dentry(void) | |
3891 | { | |
3892 | static int once; | |
3893 | ||
3894 | if (d_tracer) | |
3895 | return d_tracer; | |
3896 | ||
3e1f60b8 FW |
3897 | if (!debugfs_initialized()) |
3898 | return NULL; | |
3899 | ||
bc0c38d1 SR |
3900 | d_tracer = debugfs_create_dir("tracing", NULL); |
3901 | ||
3902 | if (!d_tracer && !once) { | |
3903 | once = 1; | |
3904 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3905 | return NULL; | |
3906 | } | |
3907 | ||
3908 | return d_tracer; | |
3909 | } | |
3910 | ||
b04cc6b1 FW |
3911 | static struct dentry *d_percpu; |
3912 | ||
3913 | struct dentry *tracing_dentry_percpu(void) | |
3914 | { | |
3915 | static int once; | |
3916 | struct dentry *d_tracer; | |
3917 | ||
3918 | if (d_percpu) | |
3919 | return d_percpu; | |
3920 | ||
3921 | d_tracer = tracing_init_dentry(); | |
3922 | ||
3923 | if (!d_tracer) | |
3924 | return NULL; | |
3925 | ||
3926 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
3927 | ||
3928 | if (!d_percpu && !once) { | |
3929 | once = 1; | |
3930 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
3931 | return NULL; | |
3932 | } | |
3933 | ||
3934 | return d_percpu; | |
3935 | } | |
3936 | ||
3937 | static void tracing_init_debugfs_percpu(long cpu) | |
3938 | { | |
3939 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 3940 | struct dentry *d_cpu; |
8656e7a2 FW |
3941 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ |
3942 | char cpu_dir[7]; | |
b04cc6b1 FW |
3943 | |
3944 | if (cpu > 999 || cpu < 0) | |
3945 | return; | |
3946 | ||
8656e7a2 FW |
3947 | sprintf(cpu_dir, "cpu%ld", cpu); |
3948 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
3949 | if (!d_cpu) { | |
3950 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
3951 | return; | |
3952 | } | |
b04cc6b1 | 3953 | |
8656e7a2 | 3954 | /* per cpu trace_pipe */ |
5452af66 FW |
3955 | trace_create_file("trace_pipe", 0444, d_cpu, |
3956 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
3957 | |
3958 | /* per cpu trace */ | |
5452af66 FW |
3959 | trace_create_file("trace", 0644, d_cpu, |
3960 | (void *) cpu, &tracing_fops); | |
7f96f93f | 3961 | |
5452af66 FW |
3962 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
3963 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 3964 | |
c8d77183 SR |
3965 | trace_create_file("stats", 0444, d_cpu, |
3966 | (void *) cpu, &tracing_stats_fops); | |
b04cc6b1 FW |
3967 | } |
3968 | ||
60a11774 SR |
3969 | #ifdef CONFIG_FTRACE_SELFTEST |
3970 | /* Let selftest have access to static functions in this file */ | |
3971 | #include "trace_selftest.c" | |
3972 | #endif | |
3973 | ||
577b785f SR |
3974 | struct trace_option_dentry { |
3975 | struct tracer_opt *opt; | |
3976 | struct tracer_flags *flags; | |
3977 | struct dentry *entry; | |
3978 | }; | |
3979 | ||
3980 | static ssize_t | |
3981 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3982 | loff_t *ppos) | |
3983 | { | |
3984 | struct trace_option_dentry *topt = filp->private_data; | |
3985 | char *buf; | |
3986 | ||
3987 | if (topt->flags->val & topt->opt->bit) | |
3988 | buf = "1\n"; | |
3989 | else | |
3990 | buf = "0\n"; | |
3991 | ||
3992 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3993 | } | |
3994 | ||
3995 | static ssize_t | |
3996 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3997 | loff_t *ppos) | |
3998 | { | |
3999 | struct trace_option_dentry *topt = filp->private_data; | |
4000 | unsigned long val; | |
4001 | char buf[64]; | |
4002 | int ret; | |
4003 | ||
4004 | if (cnt >= sizeof(buf)) | |
4005 | return -EINVAL; | |
4006 | ||
4007 | if (copy_from_user(&buf, ubuf, cnt)) | |
4008 | return -EFAULT; | |
4009 | ||
4010 | buf[cnt] = 0; | |
4011 | ||
4012 | ret = strict_strtoul(buf, 10, &val); | |
4013 | if (ret < 0) | |
4014 | return ret; | |
4015 | ||
8d18eaaf LZ |
4016 | if (val != 0 && val != 1) |
4017 | return -EINVAL; | |
577b785f | 4018 | |
8d18eaaf | 4019 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 4020 | mutex_lock(&trace_types_lock); |
8d18eaaf | 4021 | ret = __set_tracer_option(current_trace, topt->flags, |
c757bea9 | 4022 | topt->opt, !val); |
577b785f SR |
4023 | mutex_unlock(&trace_types_lock); |
4024 | if (ret) | |
4025 | return ret; | |
577b785f SR |
4026 | } |
4027 | ||
4028 | *ppos += cnt; | |
4029 | ||
4030 | return cnt; | |
4031 | } | |
4032 | ||
4033 | ||
4034 | static const struct file_operations trace_options_fops = { | |
4035 | .open = tracing_open_generic, | |
4036 | .read = trace_options_read, | |
4037 | .write = trace_options_write, | |
4038 | }; | |
4039 | ||
a8259075 SR |
4040 | static ssize_t |
4041 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4042 | loff_t *ppos) | |
4043 | { | |
4044 | long index = (long)filp->private_data; | |
4045 | char *buf; | |
4046 | ||
4047 | if (trace_flags & (1 << index)) | |
4048 | buf = "1\n"; | |
4049 | else | |
4050 | buf = "0\n"; | |
4051 | ||
4052 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4053 | } | |
4054 | ||
4055 | static ssize_t | |
4056 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4057 | loff_t *ppos) | |
4058 | { | |
4059 | long index = (long)filp->private_data; | |
4060 | char buf[64]; | |
4061 | unsigned long val; | |
4062 | int ret; | |
4063 | ||
4064 | if (cnt >= sizeof(buf)) | |
4065 | return -EINVAL; | |
4066 | ||
4067 | if (copy_from_user(&buf, ubuf, cnt)) | |
4068 | return -EFAULT; | |
4069 | ||
4070 | buf[cnt] = 0; | |
4071 | ||
4072 | ret = strict_strtoul(buf, 10, &val); | |
4073 | if (ret < 0) | |
4074 | return ret; | |
4075 | ||
f2d84b65 | 4076 | if (val != 0 && val != 1) |
a8259075 | 4077 | return -EINVAL; |
f2d84b65 | 4078 | set_tracer_flags(1 << index, val); |
a8259075 SR |
4079 | |
4080 | *ppos += cnt; | |
4081 | ||
4082 | return cnt; | |
4083 | } | |
4084 | ||
a8259075 SR |
4085 | static const struct file_operations trace_options_core_fops = { |
4086 | .open = tracing_open_generic, | |
4087 | .read = trace_options_core_read, | |
4088 | .write = trace_options_core_write, | |
4089 | }; | |
4090 | ||
5452af66 FW |
4091 | struct dentry *trace_create_file(const char *name, |
4092 | mode_t mode, | |
4093 | struct dentry *parent, | |
4094 | void *data, | |
4095 | const struct file_operations *fops) | |
4096 | { | |
4097 | struct dentry *ret; | |
4098 | ||
4099 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
4100 | if (!ret) | |
4101 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
4102 | ||
4103 | return ret; | |
4104 | } | |
4105 | ||
4106 | ||
a8259075 SR |
4107 | static struct dentry *trace_options_init_dentry(void) |
4108 | { | |
4109 | struct dentry *d_tracer; | |
4110 | static struct dentry *t_options; | |
4111 | ||
4112 | if (t_options) | |
4113 | return t_options; | |
4114 | ||
4115 | d_tracer = tracing_init_dentry(); | |
4116 | if (!d_tracer) | |
4117 | return NULL; | |
4118 | ||
4119 | t_options = debugfs_create_dir("options", d_tracer); | |
4120 | if (!t_options) { | |
4121 | pr_warning("Could not create debugfs directory 'options'\n"); | |
4122 | return NULL; | |
4123 | } | |
4124 | ||
4125 | return t_options; | |
4126 | } | |
4127 | ||
577b785f SR |
4128 | static void |
4129 | create_trace_option_file(struct trace_option_dentry *topt, | |
4130 | struct tracer_flags *flags, | |
4131 | struct tracer_opt *opt) | |
4132 | { | |
4133 | struct dentry *t_options; | |
577b785f SR |
4134 | |
4135 | t_options = trace_options_init_dentry(); | |
4136 | if (!t_options) | |
4137 | return; | |
4138 | ||
4139 | topt->flags = flags; | |
4140 | topt->opt = opt; | |
4141 | ||
5452af66 | 4142 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
4143 | &trace_options_fops); |
4144 | ||
577b785f SR |
4145 | } |
4146 | ||
4147 | static struct trace_option_dentry * | |
4148 | create_trace_option_files(struct tracer *tracer) | |
4149 | { | |
4150 | struct trace_option_dentry *topts; | |
4151 | struct tracer_flags *flags; | |
4152 | struct tracer_opt *opts; | |
4153 | int cnt; | |
4154 | ||
4155 | if (!tracer) | |
4156 | return NULL; | |
4157 | ||
4158 | flags = tracer->flags; | |
4159 | ||
4160 | if (!flags || !flags->opts) | |
4161 | return NULL; | |
4162 | ||
4163 | opts = flags->opts; | |
4164 | ||
4165 | for (cnt = 0; opts[cnt].name; cnt++) | |
4166 | ; | |
4167 | ||
0cfe8245 | 4168 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
4169 | if (!topts) |
4170 | return NULL; | |
4171 | ||
4172 | for (cnt = 0; opts[cnt].name; cnt++) | |
4173 | create_trace_option_file(&topts[cnt], flags, | |
4174 | &opts[cnt]); | |
4175 | ||
4176 | return topts; | |
4177 | } | |
4178 | ||
4179 | static void | |
4180 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
4181 | { | |
4182 | int cnt; | |
4183 | ||
4184 | if (!topts) | |
4185 | return; | |
4186 | ||
4187 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
4188 | if (topts[cnt].entry) | |
4189 | debugfs_remove(topts[cnt].entry); | |
4190 | } | |
4191 | ||
4192 | kfree(topts); | |
4193 | } | |
4194 | ||
a8259075 SR |
4195 | static struct dentry * |
4196 | create_trace_option_core_file(const char *option, long index) | |
4197 | { | |
4198 | struct dentry *t_options; | |
a8259075 SR |
4199 | |
4200 | t_options = trace_options_init_dentry(); | |
4201 | if (!t_options) | |
4202 | return NULL; | |
4203 | ||
5452af66 | 4204 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 4205 | &trace_options_core_fops); |
a8259075 SR |
4206 | } |
4207 | ||
4208 | static __init void create_trace_options_dir(void) | |
4209 | { | |
4210 | struct dentry *t_options; | |
a8259075 SR |
4211 | int i; |
4212 | ||
4213 | t_options = trace_options_init_dentry(); | |
4214 | if (!t_options) | |
4215 | return; | |
4216 | ||
5452af66 FW |
4217 | for (i = 0; trace_options[i]; i++) |
4218 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4219 | } |
4220 | ||
b5ad384e | 4221 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4222 | { |
4223 | struct dentry *d_tracer; | |
b04cc6b1 | 4224 | int cpu; |
bc0c38d1 | 4225 | |
7e53bd42 LJ |
4226 | trace_access_lock_init(); |
4227 | ||
bc0c38d1 SR |
4228 | d_tracer = tracing_init_dentry(); |
4229 | ||
5452af66 FW |
4230 | trace_create_file("tracing_enabled", 0644, d_tracer, |
4231 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 4232 | |
5452af66 FW |
4233 | trace_create_file("trace_options", 0644, d_tracer, |
4234 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4235 | |
5452af66 FW |
4236 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4237 | NULL, &tracing_cpumask_fops); | |
4238 | ||
4239 | trace_create_file("trace", 0644, d_tracer, | |
4240 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 4241 | |
5452af66 FW |
4242 | trace_create_file("available_tracers", 0444, d_tracer, |
4243 | &global_trace, &show_traces_fops); | |
4244 | ||
339ae5d3 | 4245 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4246 | &global_trace, &set_tracer_fops); |
4247 | ||
5d4a9dba | 4248 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
4249 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
4250 | &tracing_max_latency, &tracing_max_lat_fops); | |
4251 | ||
4252 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4253 | &tracing_thresh, &tracing_max_lat_fops); | |
5d4a9dba | 4254 | #endif |
a8259075 | 4255 | |
339ae5d3 | 4256 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4257 | NULL, &tracing_readme_fops); |
4258 | ||
4259 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4260 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4261 | |
4262 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
4263 | &global_trace, &tracing_entries_fops); | |
4264 | ||
4265 | trace_create_file("trace_marker", 0220, d_tracer, | |
4266 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4267 | |
69abe6a5 AP |
4268 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4269 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 4270 | |
5079f326 Z |
4271 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
4272 | &trace_clock_fops); | |
4273 | ||
bc0c38d1 | 4274 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4275 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4276 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4277 | #endif |
d618b3e6 IM |
4278 | #ifdef CONFIG_SYSPROF_TRACER |
4279 | init_tracer_sysprof_debugfs(d_tracer); | |
4280 | #endif | |
b04cc6b1 | 4281 | |
5452af66 FW |
4282 | create_trace_options_dir(); |
4283 | ||
b04cc6b1 FW |
4284 | for_each_tracing_cpu(cpu) |
4285 | tracing_init_debugfs_percpu(cpu); | |
4286 | ||
b5ad384e | 4287 | return 0; |
bc0c38d1 SR |
4288 | } |
4289 | ||
3f5a54e3 SR |
4290 | static int trace_panic_handler(struct notifier_block *this, |
4291 | unsigned long event, void *unused) | |
4292 | { | |
944ac425 SR |
4293 | if (ftrace_dump_on_oops) |
4294 | ftrace_dump(); | |
3f5a54e3 SR |
4295 | return NOTIFY_OK; |
4296 | } | |
4297 | ||
4298 | static struct notifier_block trace_panic_notifier = { | |
4299 | .notifier_call = trace_panic_handler, | |
4300 | .next = NULL, | |
4301 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4302 | }; | |
4303 | ||
4304 | static int trace_die_handler(struct notifier_block *self, | |
4305 | unsigned long val, | |
4306 | void *data) | |
4307 | { | |
4308 | switch (val) { | |
4309 | case DIE_OOPS: | |
944ac425 SR |
4310 | if (ftrace_dump_on_oops) |
4311 | ftrace_dump(); | |
3f5a54e3 SR |
4312 | break; |
4313 | default: | |
4314 | break; | |
4315 | } | |
4316 | return NOTIFY_OK; | |
4317 | } | |
4318 | ||
4319 | static struct notifier_block trace_die_notifier = { | |
4320 | .notifier_call = trace_die_handler, | |
4321 | .priority = 200 | |
4322 | }; | |
4323 | ||
4324 | /* | |
4325 | * printk is set to max of 1024, we really don't need it that big. | |
4326 | * Nothing should be printing 1000 characters anyway. | |
4327 | */ | |
4328 | #define TRACE_MAX_PRINT 1000 | |
4329 | ||
4330 | /* | |
4331 | * Define here KERN_TRACE so that we have one place to modify | |
4332 | * it if we decide to change what log level the ftrace dump | |
4333 | * should be at. | |
4334 | */ | |
428aee14 | 4335 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
4336 | |
4337 | static void | |
4338 | trace_printk_seq(struct trace_seq *s) | |
4339 | { | |
4340 | /* Probably should print a warning here. */ | |
4341 | if (s->len >= 1000) | |
4342 | s->len = 1000; | |
4343 | ||
4344 | /* should be zero ended, but we are paranoid. */ | |
4345 | s->buffer[s->len] = 0; | |
4346 | ||
4347 | printk(KERN_TRACE "%s", s->buffer); | |
4348 | ||
f9520750 | 4349 | trace_seq_init(s); |
3f5a54e3 SR |
4350 | } |
4351 | ||
cf586b61 | 4352 | static void __ftrace_dump(bool disable_tracing) |
3f5a54e3 | 4353 | { |
445c8951 | 4354 | static arch_spinlock_t ftrace_dump_lock = |
edc35bd7 | 4355 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
3f5a54e3 SR |
4356 | /* use static because iter can be a bit big for the stack */ |
4357 | static struct trace_iterator iter; | |
cf586b61 | 4358 | unsigned int old_userobj; |
3f5a54e3 | 4359 | static int dump_ran; |
d769041f SR |
4360 | unsigned long flags; |
4361 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4362 | |
4363 | /* only one dump */ | |
cd891ae0 | 4364 | local_irq_save(flags); |
0199c4e6 | 4365 | arch_spin_lock(&ftrace_dump_lock); |
3f5a54e3 SR |
4366 | if (dump_ran) |
4367 | goto out; | |
4368 | ||
4369 | dump_ran = 1; | |
4370 | ||
0ee6b6cf | 4371 | tracing_off(); |
cf586b61 FW |
4372 | |
4373 | if (disable_tracing) | |
4374 | ftrace_kill(); | |
3f5a54e3 | 4375 | |
d769041f SR |
4376 | for_each_tracing_cpu(cpu) { |
4377 | atomic_inc(&global_trace.data[cpu]->disabled); | |
4378 | } | |
4379 | ||
cf586b61 FW |
4380 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4381 | ||
b54d3de9 TE |
4382 | /* don't look at user memory in panic mode */ |
4383 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4384 | ||
3f5a54e3 SR |
4385 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
4386 | ||
e543ad76 | 4387 | /* Simulate the iterator */ |
3f5a54e3 SR |
4388 | iter.tr = &global_trace; |
4389 | iter.trace = current_trace; | |
e543ad76 | 4390 | iter.cpu_file = TRACE_PIPE_ALL_CPU; |
3f5a54e3 SR |
4391 | |
4392 | /* | |
4393 | * We need to stop all tracing on all CPUS to read the | |
4394 | * the next buffer. This is a bit expensive, but is | |
4395 | * not done often. We fill all what we can read, | |
4396 | * and then release the locks again. | |
4397 | */ | |
4398 | ||
3f5a54e3 SR |
4399 | while (!trace_empty(&iter)) { |
4400 | ||
4401 | if (!cnt) | |
4402 | printk(KERN_TRACE "---------------------------------\n"); | |
4403 | ||
4404 | cnt++; | |
4405 | ||
4406 | /* reset all but tr, trace, and overruns */ | |
4407 | memset(&iter.seq, 0, | |
4408 | sizeof(struct trace_iterator) - | |
4409 | offsetof(struct trace_iterator, seq)); | |
4410 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4411 | iter.pos = -1; | |
4412 | ||
4413 | if (find_next_entry_inc(&iter) != NULL) { | |
74e7ff8c LJ |
4414 | int ret; |
4415 | ||
4416 | ret = print_trace_line(&iter); | |
4417 | if (ret != TRACE_TYPE_NO_CONSUME) | |
4418 | trace_consume(&iter); | |
3f5a54e3 SR |
4419 | } |
4420 | ||
4421 | trace_printk_seq(&iter.seq); | |
4422 | } | |
4423 | ||
4424 | if (!cnt) | |
4425 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4426 | else | |
4427 | printk(KERN_TRACE "---------------------------------\n"); | |
4428 | ||
cf586b61 FW |
4429 | /* Re-enable tracing if requested */ |
4430 | if (!disable_tracing) { | |
4431 | trace_flags |= old_userobj; | |
4432 | ||
4433 | for_each_tracing_cpu(cpu) { | |
4434 | atomic_dec(&global_trace.data[cpu]->disabled); | |
4435 | } | |
4436 | tracing_on(); | |
4437 | } | |
4438 | ||
3f5a54e3 | 4439 | out: |
0199c4e6 | 4440 | arch_spin_unlock(&ftrace_dump_lock); |
cd891ae0 | 4441 | local_irq_restore(flags); |
3f5a54e3 SR |
4442 | } |
4443 | ||
cf586b61 FW |
4444 | /* By default: disable tracing after the dump */ |
4445 | void ftrace_dump(void) | |
4446 | { | |
4447 | __ftrace_dump(true); | |
4448 | } | |
4449 | ||
3928a8a2 | 4450 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4451 | { |
73c5162a | 4452 | int ring_buf_size; |
4c11d7ae | 4453 | int i; |
9e01c1b7 | 4454 | int ret = -ENOMEM; |
4c11d7ae | 4455 | |
9e01c1b7 RR |
4456 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4457 | goto out; | |
4458 | ||
4459 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4460 | goto out_free_buffer_mask; | |
4c11d7ae | 4461 | |
73c5162a SR |
4462 | /* To save memory, keep the ring buffer size to its minimum */ |
4463 | if (ring_buffer_expanded) | |
4464 | ring_buf_size = trace_buf_size; | |
4465 | else | |
4466 | ring_buf_size = 1; | |
4467 | ||
9e01c1b7 RR |
4468 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4469 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
4470 | ||
4471 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
73c5162a | 4472 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4473 | TRACE_BUFFER_FLAGS); |
4474 | if (!global_trace.buffer) { | |
4475 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4476 | WARN_ON(1); | |
9e01c1b7 | 4477 | goto out_free_cpumask; |
4c11d7ae | 4478 | } |
3928a8a2 | 4479 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4480 | |
9e01c1b7 | 4481 | |
4c11d7ae | 4482 | #ifdef CONFIG_TRACER_MAX_TRACE |
73c5162a | 4483 | max_tr.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4484 | TRACE_BUFFER_FLAGS); |
4485 | if (!max_tr.buffer) { | |
4486 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4487 | WARN_ON(1); | |
4488 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4489 | goto out_free_cpumask; |
4c11d7ae | 4490 | } |
3928a8a2 SR |
4491 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
4492 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 4493 | #endif |
ab46428c | 4494 | |
4c11d7ae | 4495 | /* Allocate the first page for all buffers */ |
ab46428c | 4496 | for_each_tracing_cpu(i) { |
566b0aaf | 4497 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
9705f69e | 4498 | max_tr.data[i] = &per_cpu(max_tr_data, i); |
4c11d7ae | 4499 | } |
bc0c38d1 | 4500 | |
bc0c38d1 SR |
4501 | trace_init_cmdlines(); |
4502 | ||
43a15386 | 4503 | register_tracer(&nop_trace); |
79fb0768 | 4504 | current_trace = &nop_trace; |
b5ad384e FW |
4505 | #ifdef CONFIG_BOOT_TRACER |
4506 | register_tracer(&boot_tracer); | |
b5ad384e | 4507 | #endif |
60a11774 SR |
4508 | /* All seems OK, enable tracing */ |
4509 | tracing_disabled = 0; | |
3928a8a2 | 4510 | |
3f5a54e3 SR |
4511 | atomic_notifier_chain_register(&panic_notifier_list, |
4512 | &trace_panic_notifier); | |
4513 | ||
4514 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4515 | |
4516 | return 0; | |
3f5a54e3 | 4517 | |
9e01c1b7 RR |
4518 | out_free_cpumask: |
4519 | free_cpumask_var(tracing_cpumask); | |
4520 | out_free_buffer_mask: | |
4521 | free_cpumask_var(tracing_buffer_mask); | |
4522 | out: | |
4523 | return ret; | |
bc0c38d1 | 4524 | } |
b2821ae6 SR |
4525 | |
4526 | __init static int clear_boot_tracer(void) | |
4527 | { | |
4528 | /* | |
4529 | * The default tracer at boot buffer is an init section. | |
4530 | * This function is called in lateinit. If we did not | |
4531 | * find the boot tracer, then clear it out, to prevent | |
4532 | * later registration from accessing the buffer that is | |
4533 | * about to be freed. | |
4534 | */ | |
4535 | if (!default_bootup_tracer) | |
4536 | return 0; | |
4537 | ||
4538 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4539 | default_bootup_tracer); | |
4540 | default_bootup_tracer = NULL; | |
4541 | ||
4542 | return 0; | |
4543 | } | |
4544 | ||
b5ad384e FW |
4545 | early_initcall(tracer_alloc_buffers); |
4546 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4547 | late_initcall(clear_boot_tracer); |