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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> |
bc0c38d1 | 15 | #include <linux/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> |
bc0c38d1 SR |
35 | #include <linux/ctype.h> |
36 | #include <linux/init.h> | |
2a2cc8f7 | 37 | #include <linux/poll.h> |
bc0c38d1 SR |
38 | #include <linux/gfp.h> |
39 | #include <linux/fs.h> | |
86387f7e | 40 | |
bc0c38d1 | 41 | #include "trace.h" |
f0868d1e | 42 | #include "trace_output.h" |
bc0c38d1 | 43 | |
3928a8a2 SR |
44 | #define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE) |
45 | ||
73c5162a SR |
46 | /* |
47 | * On boot up, the ring buffer is set to the minimum size, so that | |
48 | * we do not waste memory on systems that are not using tracing. | |
49 | */ | |
020e5f85 | 50 | int ring_buffer_expanded; |
73c5162a | 51 | |
8e1b82e0 FW |
52 | /* |
53 | * We need to change this state when a selftest is running. | |
ff32504f FW |
54 | * A selftest will lurk into the ring-buffer to count the |
55 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 56 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
57 | * at the same time, giving false positive or negative results. |
58 | */ | |
8e1b82e0 | 59 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 60 | |
b2821ae6 SR |
61 | /* |
62 | * If a tracer is running, we do not want to run SELFTEST. | |
63 | */ | |
020e5f85 | 64 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 65 | |
adf9f195 FW |
66 | /* For tracers that don't implement custom flags */ |
67 | static struct tracer_opt dummy_tracer_opt[] = { | |
68 | { } | |
69 | }; | |
70 | ||
71 | static struct tracer_flags dummy_tracer_flags = { | |
72 | .val = 0, | |
73 | .opts = dummy_tracer_opt | |
74 | }; | |
75 | ||
76 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
77 | { | |
78 | return 0; | |
79 | } | |
0f048701 SR |
80 | |
81 | /* | |
82 | * Kill all tracing for good (never come back). | |
83 | * It is initialized to 1 but will turn to zero if the initialization | |
84 | * of the tracer is successful. But that is the only place that sets | |
85 | * this back to zero. | |
86 | */ | |
4fd27358 | 87 | static int tracing_disabled = 1; |
0f048701 | 88 | |
9288f99a | 89 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f SR |
90 | |
91 | static inline void ftrace_disable_cpu(void) | |
92 | { | |
93 | preempt_disable(); | |
9288f99a | 94 | __this_cpu_inc(per_cpu_var(ftrace_cpu_disabled)); |
d769041f SR |
95 | } |
96 | ||
97 | static inline void ftrace_enable_cpu(void) | |
98 | { | |
9288f99a | 99 | __this_cpu_dec(per_cpu_var(ftrace_cpu_disabled)); |
d769041f SR |
100 | preempt_enable(); |
101 | } | |
102 | ||
9e01c1b7 | 103 | static cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 104 | |
b04cc6b1 FW |
105 | /* Define which cpu buffers are currently read in trace_pipe */ |
106 | static cpumask_var_t tracing_reader_cpumask; | |
107 | ||
ab46428c | 108 | #define for_each_tracing_cpu(cpu) \ |
9e01c1b7 | 109 | for_each_cpu(cpu, tracing_buffer_mask) |
ab46428c | 110 | |
944ac425 SR |
111 | /* |
112 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
113 | * | |
114 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
115 | * is set, then ftrace_dump is called. This will output the contents | |
116 | * of the ftrace buffers to the console. This is very useful for | |
117 | * capturing traces that lead to crashes and outputing it to a | |
118 | * serial console. | |
119 | * | |
120 | * It is default off, but you can enable it with either specifying | |
121 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
122 | * /proc/sys/kernel/ftrace_dump_on_oops to true. | |
123 | */ | |
124 | int ftrace_dump_on_oops; | |
125 | ||
b2821ae6 SR |
126 | static int tracing_set_tracer(const char *buf); |
127 | ||
ee6c2c1b LZ |
128 | #define MAX_TRACER_SIZE 100 |
129 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 130 | static char *default_bootup_tracer; |
d9e54076 PZ |
131 | |
132 | static int __init set_ftrace(char *str) | |
133 | { | |
ee6c2c1b | 134 | strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 135 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a SR |
136 | /* We are using ftrace early, expand it */ |
137 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
138 | return 1; |
139 | } | |
b2821ae6 | 140 | __setup("ftrace=", set_ftrace); |
d9e54076 | 141 | |
944ac425 SR |
142 | static int __init set_ftrace_dump_on_oops(char *str) |
143 | { | |
144 | ftrace_dump_on_oops = 1; | |
145 | return 1; | |
146 | } | |
147 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 148 | |
cf8e3474 | 149 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
150 | { |
151 | nsec += 500; | |
152 | do_div(nsec, 1000); | |
153 | return nsec; | |
154 | } | |
155 | ||
4fcdae83 SR |
156 | /* |
157 | * The global_trace is the descriptor that holds the tracing | |
158 | * buffers for the live tracing. For each CPU, it contains | |
159 | * a link list of pages that will store trace entries. The | |
160 | * page descriptor of the pages in the memory is used to hold | |
161 | * the link list by linking the lru item in the page descriptor | |
162 | * to each of the pages in the buffer per CPU. | |
163 | * | |
164 | * For each active CPU there is a data field that holds the | |
165 | * pages for the buffer for that CPU. Each CPU has the same number | |
166 | * of pages allocated for its buffer. | |
167 | */ | |
bc0c38d1 SR |
168 | static struct trace_array global_trace; |
169 | ||
170 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
171 | ||
e77405ad SR |
172 | int filter_current_check_discard(struct ring_buffer *buffer, |
173 | struct ftrace_event_call *call, void *rec, | |
eb02ce01 TZ |
174 | struct ring_buffer_event *event) |
175 | { | |
e77405ad | 176 | return filter_check_discard(call, rec, buffer, event); |
eb02ce01 | 177 | } |
17c873ec | 178 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 179 | |
37886f6a SR |
180 | cycle_t ftrace_now(int cpu) |
181 | { | |
182 | u64 ts; | |
183 | ||
184 | /* Early boot up does not have a buffer yet */ | |
185 | if (!global_trace.buffer) | |
186 | return trace_clock_local(); | |
187 | ||
188 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
189 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
190 | ||
191 | return ts; | |
192 | } | |
bc0c38d1 | 193 | |
4fcdae83 SR |
194 | /* |
195 | * The max_tr is used to snapshot the global_trace when a maximum | |
196 | * latency is reached. Some tracers will use this to store a maximum | |
197 | * trace while it continues examining live traces. | |
198 | * | |
199 | * The buffers for the max_tr are set up the same as the global_trace. | |
200 | * When a snapshot is taken, the link list of the max_tr is swapped | |
201 | * with the link list of the global_trace and the buffers are reset for | |
202 | * the global_trace so the tracing can continue. | |
203 | */ | |
bc0c38d1 SR |
204 | static struct trace_array max_tr; |
205 | ||
9705f69e | 206 | static DEFINE_PER_CPU(struct trace_array_cpu, max_tr_data); |
bc0c38d1 | 207 | |
4fcdae83 | 208 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 209 | static int tracer_enabled = 1; |
4fcdae83 | 210 | |
9036990d SR |
211 | /** |
212 | * tracing_is_enabled - return tracer_enabled status | |
213 | * | |
214 | * This function is used by other tracers to know the status | |
215 | * of the tracer_enabled flag. Tracers may use this function | |
216 | * to know if it should enable their features when starting | |
217 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
218 | */ | |
219 | int tracing_is_enabled(void) | |
220 | { | |
221 | return tracer_enabled; | |
222 | } | |
223 | ||
4fcdae83 | 224 | /* |
3928a8a2 SR |
225 | * trace_buf_size is the size in bytes that is allocated |
226 | * for a buffer. Note, the number of bytes is always rounded | |
227 | * to page size. | |
3f5a54e3 SR |
228 | * |
229 | * This number is purposely set to a low number of 16384. | |
230 | * If the dump on oops happens, it will be much appreciated | |
231 | * to not have to wait for all that output. Anyway this can be | |
232 | * boot time and run time configurable. | |
4fcdae83 | 233 | */ |
3928a8a2 | 234 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 235 | |
3928a8a2 | 236 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 237 | |
4fcdae83 | 238 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 239 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
240 | |
241 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 242 | static struct tracer *current_trace __read_mostly; |
4fcdae83 | 243 | |
4fcdae83 SR |
244 | /* |
245 | * trace_types_lock is used to protect the trace_types list. | |
246 | * This lock is also used to keep user access serialized. | |
247 | * Accesses from userspace will grab this lock while userspace | |
248 | * activities happen inside the kernel. | |
249 | */ | |
bc0c38d1 | 250 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
251 | |
252 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
253 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
254 | ||
ee6bce52 | 255 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 256 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a SR |
257 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
258 | TRACE_ITER_GRAPH_TIME; | |
4e655519 | 259 | |
b8de7bd1 SR |
260 | static int trace_stop_count; |
261 | static DEFINE_SPINLOCK(tracing_start_lock); | |
262 | ||
4fcdae83 SR |
263 | /** |
264 | * trace_wake_up - wake up tasks waiting for trace input | |
265 | * | |
266 | * Simply wakes up any task that is blocked on the trace_wait | |
267 | * queue. These is used with trace_poll for tasks polling the trace. | |
268 | */ | |
4e655519 IM |
269 | void trace_wake_up(void) |
270 | { | |
89f19f04 AM |
271 | int cpu; |
272 | ||
273 | if (trace_flags & TRACE_ITER_BLOCK) | |
274 | return; | |
017730c1 IM |
275 | /* |
276 | * The runqueue_is_locked() can fail, but this is the best we | |
277 | * have for now: | |
278 | */ | |
89f19f04 AM |
279 | cpu = get_cpu(); |
280 | if (!runqueue_is_locked(cpu)) | |
4e655519 | 281 | wake_up(&trace_wait); |
89f19f04 | 282 | put_cpu(); |
4e655519 | 283 | } |
bc0c38d1 | 284 | |
3928a8a2 | 285 | static int __init set_buf_size(char *str) |
bc0c38d1 | 286 | { |
3928a8a2 | 287 | unsigned long buf_size; |
c6caeeb1 | 288 | |
bc0c38d1 SR |
289 | if (!str) |
290 | return 0; | |
9d612bef | 291 | buf_size = memparse(str, &str); |
c6caeeb1 | 292 | /* nr_entries can not be zero */ |
9d612bef | 293 | if (buf_size == 0) |
c6caeeb1 | 294 | return 0; |
3928a8a2 | 295 | trace_buf_size = buf_size; |
bc0c38d1 SR |
296 | return 1; |
297 | } | |
3928a8a2 | 298 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 299 | |
57f50be1 SR |
300 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
301 | { | |
302 | return nsecs / 1000; | |
303 | } | |
304 | ||
4fcdae83 | 305 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
306 | static const char *trace_options[] = { |
307 | "print-parent", | |
308 | "sym-offset", | |
309 | "sym-addr", | |
310 | "verbose", | |
f9896bf3 | 311 | "raw", |
5e3ca0ec | 312 | "hex", |
cb0f12aa | 313 | "bin", |
2a2cc8f7 | 314 | "block", |
86387f7e | 315 | "stacktrace", |
4ac3ba41 | 316 | "sched-tree", |
5e1607a0 | 317 | "trace_printk", |
b2a866f9 | 318 | "ftrace_preempt", |
9f029e83 | 319 | "branch", |
12ef7d44 | 320 | "annotate", |
02b67518 | 321 | "userstacktrace", |
b54d3de9 | 322 | "sym-userobj", |
66896a85 | 323 | "printk-msg-only", |
c4a8e8be | 324 | "context-info", |
c032ef64 | 325 | "latency-format", |
be6f164a | 326 | "sleep-time", |
a2a16d6a | 327 | "graph-time", |
bc0c38d1 SR |
328 | NULL |
329 | }; | |
330 | ||
5079f326 Z |
331 | static struct { |
332 | u64 (*func)(void); | |
333 | const char *name; | |
334 | } trace_clocks[] = { | |
335 | { trace_clock_local, "local" }, | |
336 | { trace_clock_global, "global" }, | |
337 | }; | |
338 | ||
339 | int trace_clock_id; | |
340 | ||
b63f39ea | 341 | /* |
342 | * trace_parser_get_init - gets the buffer for trace parser | |
343 | */ | |
344 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
345 | { | |
346 | memset(parser, 0, sizeof(*parser)); | |
347 | ||
348 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
349 | if (!parser->buffer) | |
350 | return 1; | |
351 | ||
352 | parser->size = size; | |
353 | return 0; | |
354 | } | |
355 | ||
356 | /* | |
357 | * trace_parser_put - frees the buffer for trace parser | |
358 | */ | |
359 | void trace_parser_put(struct trace_parser *parser) | |
360 | { | |
361 | kfree(parser->buffer); | |
362 | } | |
363 | ||
364 | /* | |
365 | * trace_get_user - reads the user input string separated by space | |
366 | * (matched by isspace(ch)) | |
367 | * | |
368 | * For each string found the 'struct trace_parser' is updated, | |
369 | * and the function returns. | |
370 | * | |
371 | * Returns number of bytes read. | |
372 | * | |
373 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
374 | */ | |
375 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
376 | size_t cnt, loff_t *ppos) | |
377 | { | |
378 | char ch; | |
379 | size_t read = 0; | |
380 | ssize_t ret; | |
381 | ||
382 | if (!*ppos) | |
383 | trace_parser_clear(parser); | |
384 | ||
385 | ret = get_user(ch, ubuf++); | |
386 | if (ret) | |
387 | goto out; | |
388 | ||
389 | read++; | |
390 | cnt--; | |
391 | ||
392 | /* | |
393 | * The parser is not finished with the last write, | |
394 | * continue reading the user input without skipping spaces. | |
395 | */ | |
396 | if (!parser->cont) { | |
397 | /* skip white space */ | |
398 | while (cnt && isspace(ch)) { | |
399 | ret = get_user(ch, ubuf++); | |
400 | if (ret) | |
401 | goto out; | |
402 | read++; | |
403 | cnt--; | |
404 | } | |
405 | ||
406 | /* only spaces were written */ | |
407 | if (isspace(ch)) { | |
408 | *ppos += read; | |
409 | ret = read; | |
410 | goto out; | |
411 | } | |
412 | ||
413 | parser->idx = 0; | |
414 | } | |
415 | ||
416 | /* read the non-space input */ | |
417 | while (cnt && !isspace(ch)) { | |
3c235a33 | 418 | if (parser->idx < parser->size - 1) |
b63f39ea | 419 | parser->buffer[parser->idx++] = ch; |
420 | else { | |
421 | ret = -EINVAL; | |
422 | goto out; | |
423 | } | |
424 | ret = get_user(ch, ubuf++); | |
425 | if (ret) | |
426 | goto out; | |
427 | read++; | |
428 | cnt--; | |
429 | } | |
430 | ||
431 | /* We either got finished input or we have to wait for another call. */ | |
432 | if (isspace(ch)) { | |
433 | parser->buffer[parser->idx] = 0; | |
434 | parser->cont = false; | |
435 | } else { | |
436 | parser->cont = true; | |
437 | parser->buffer[parser->idx++] = ch; | |
438 | } | |
439 | ||
440 | *ppos += read; | |
441 | ret = read; | |
442 | ||
443 | out: | |
444 | return ret; | |
445 | } | |
446 | ||
6c6c2796 PP |
447 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
448 | { | |
449 | int len; | |
450 | int ret; | |
451 | ||
2dc5d12b SR |
452 | if (!cnt) |
453 | return 0; | |
454 | ||
6c6c2796 PP |
455 | if (s->len <= s->readpos) |
456 | return -EBUSY; | |
457 | ||
458 | len = s->len - s->readpos; | |
459 | if (cnt > len) | |
460 | cnt = len; | |
461 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 462 | if (ret == cnt) |
6c6c2796 PP |
463 | return -EFAULT; |
464 | ||
2dc5d12b SR |
465 | cnt -= ret; |
466 | ||
e74da523 | 467 | s->readpos += cnt; |
6c6c2796 | 468 | return cnt; |
214023c3 SR |
469 | } |
470 | ||
b8b94265 | 471 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
472 | { |
473 | int len; | |
474 | void *ret; | |
475 | ||
476 | if (s->len <= s->readpos) | |
477 | return -EBUSY; | |
478 | ||
479 | len = s->len - s->readpos; | |
480 | if (cnt > len) | |
481 | cnt = len; | |
482 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
483 | if (!ret) | |
484 | return -EFAULT; | |
485 | ||
e74da523 | 486 | s->readpos += cnt; |
3c56819b EGM |
487 | return cnt; |
488 | } | |
489 | ||
5d4a9dba SR |
490 | /* |
491 | * ftrace_max_lock is used to protect the swapping of buffers | |
492 | * when taking a max snapshot. The buffers themselves are | |
493 | * protected by per_cpu spinlocks. But the action of the swap | |
494 | * needs its own lock. | |
495 | * | |
496 | * This is defined as a raw_spinlock_t in order to help | |
497 | * with performance when lockdep debugging is enabled. | |
498 | * | |
499 | * It is also used in other places outside the update_max_tr | |
500 | * so it needs to be defined outside of the | |
501 | * CONFIG_TRACER_MAX_TRACE. | |
502 | */ | |
503 | static raw_spinlock_t ftrace_max_lock = | |
504 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
505 | ||
506 | #ifdef CONFIG_TRACER_MAX_TRACE | |
507 | unsigned long __read_mostly tracing_max_latency; | |
508 | unsigned long __read_mostly tracing_thresh; | |
509 | ||
510 | /* | |
511 | * Copy the new maximum trace into the separate maximum-trace | |
512 | * structure. (this way the maximum trace is permanently saved, | |
513 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
514 | */ | |
515 | static void | |
516 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
517 | { | |
518 | struct trace_array_cpu *data = tr->data[cpu]; | |
8248ac05 | 519 | struct trace_array_cpu *max_data = tr->data[cpu]; |
5d4a9dba SR |
520 | |
521 | max_tr.cpu = cpu; | |
522 | max_tr.time_start = data->preempt_timestamp; | |
523 | ||
8248ac05 SR |
524 | max_data = max_tr.data[cpu]; |
525 | max_data->saved_latency = tracing_max_latency; | |
526 | max_data->critical_start = data->critical_start; | |
527 | max_data->critical_end = data->critical_end; | |
5d4a9dba SR |
528 | |
529 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
8248ac05 SR |
530 | max_data->pid = tsk->pid; |
531 | max_data->uid = task_uid(tsk); | |
532 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
533 | max_data->policy = tsk->policy; | |
534 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
535 | |
536 | /* record this tasks comm */ | |
537 | tracing_record_cmdline(tsk); | |
538 | } | |
539 | ||
4fcdae83 SR |
540 | /** |
541 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
542 | * @tr: tracer | |
543 | * @tsk: the task with the latency | |
544 | * @cpu: The cpu that initiated the trace. | |
545 | * | |
546 | * Flip the buffers between the @tr and the max_tr and record information | |
547 | * about which task was the cause of this latency. | |
548 | */ | |
e309b41d | 549 | void |
bc0c38d1 SR |
550 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
551 | { | |
3928a8a2 | 552 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 553 | |
b8de7bd1 SR |
554 | if (trace_stop_count) |
555 | return; | |
556 | ||
4c11d7ae | 557 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 558 | __raw_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
559 | |
560 | tr->buffer = max_tr.buffer; | |
561 | max_tr.buffer = buf; | |
562 | ||
bc0c38d1 | 563 | __update_max_tr(tr, tsk, cpu); |
92205c23 | 564 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
565 | } |
566 | ||
567 | /** | |
568 | * update_max_tr_single - only copy one trace over, and reset the rest | |
569 | * @tr - tracer | |
570 | * @tsk - task with the latency | |
571 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
572 | * |
573 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 574 | */ |
e309b41d | 575 | void |
bc0c38d1 SR |
576 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
577 | { | |
3928a8a2 | 578 | int ret; |
bc0c38d1 | 579 | |
b8de7bd1 SR |
580 | if (trace_stop_count) |
581 | return; | |
582 | ||
4c11d7ae | 583 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 584 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 585 | |
d769041f SR |
586 | ftrace_disable_cpu(); |
587 | ||
3928a8a2 SR |
588 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); |
589 | ||
e8165dbb SR |
590 | if (ret == -EBUSY) { |
591 | /* | |
592 | * We failed to swap the buffer due to a commit taking | |
593 | * place on this CPU. We fail to record, but we reset | |
594 | * the max trace buffer (no one writes directly to it) | |
595 | * and flag that it failed. | |
596 | */ | |
597 | trace_array_printk(&max_tr, _THIS_IP_, | |
598 | "Failed to swap buffers due to commit in progress\n"); | |
599 | } | |
600 | ||
d769041f SR |
601 | ftrace_enable_cpu(); |
602 | ||
e8165dbb | 603 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
604 | |
605 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 606 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 607 | } |
5d4a9dba | 608 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 609 | |
4fcdae83 SR |
610 | /** |
611 | * register_tracer - register a tracer with the ftrace system. | |
612 | * @type - the plugin for the tracer | |
613 | * | |
614 | * Register a new plugin tracer. | |
615 | */ | |
bc0c38d1 | 616 | int register_tracer(struct tracer *type) |
e7669b8e HE |
617 | __releases(kernel_lock) |
618 | __acquires(kernel_lock) | |
bc0c38d1 SR |
619 | { |
620 | struct tracer *t; | |
bc0c38d1 SR |
621 | int ret = 0; |
622 | ||
623 | if (!type->name) { | |
624 | pr_info("Tracer must have a name\n"); | |
625 | return -1; | |
626 | } | |
627 | ||
ee6c2c1b LZ |
628 | if (strlen(type->name) > MAX_TRACER_SIZE) { |
629 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); | |
630 | return -1; | |
631 | } | |
632 | ||
86fa2f60 IM |
633 | /* |
634 | * When this gets called we hold the BKL which means that | |
635 | * preemption is disabled. Various trace selftests however | |
636 | * need to disable and enable preemption for successful tests. | |
637 | * So we drop the BKL here and grab it after the tests again. | |
638 | */ | |
639 | unlock_kernel(); | |
bc0c38d1 | 640 | mutex_lock(&trace_types_lock); |
86fa2f60 | 641 | |
8e1b82e0 FW |
642 | tracing_selftest_running = true; |
643 | ||
bc0c38d1 SR |
644 | for (t = trace_types; t; t = t->next) { |
645 | if (strcmp(type->name, t->name) == 0) { | |
646 | /* already found */ | |
ee6c2c1b | 647 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
648 | type->name); |
649 | ret = -1; | |
650 | goto out; | |
651 | } | |
652 | } | |
653 | ||
adf9f195 FW |
654 | if (!type->set_flag) |
655 | type->set_flag = &dummy_set_flag; | |
656 | if (!type->flags) | |
657 | type->flags = &dummy_tracer_flags; | |
658 | else | |
659 | if (!type->flags->opts) | |
660 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
661 | if (!type->wait_pipe) |
662 | type->wait_pipe = default_wait_pipe; | |
663 | ||
adf9f195 | 664 | |
60a11774 | 665 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 666 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 667 | struct tracer *saved_tracer = current_trace; |
60a11774 | 668 | struct trace_array *tr = &global_trace; |
ff32504f | 669 | |
60a11774 SR |
670 | /* |
671 | * Run a selftest on this tracer. | |
672 | * Here we reset the trace buffer, and set the current | |
673 | * tracer to be this tracer. The tracer can then run some | |
674 | * internal tracing to verify that everything is in order. | |
675 | * If we fail, we do not register this tracer. | |
676 | */ | |
76f0d073 | 677 | tracing_reset_online_cpus(tr); |
86fa2f60 | 678 | |
60a11774 | 679 | current_trace = type; |
60a11774 SR |
680 | /* the test is responsible for initializing and enabling */ |
681 | pr_info("Testing tracer %s: ", type->name); | |
682 | ret = type->selftest(type, tr); | |
683 | /* the test is responsible for resetting too */ | |
684 | current_trace = saved_tracer; | |
60a11774 SR |
685 | if (ret) { |
686 | printk(KERN_CONT "FAILED!\n"); | |
687 | goto out; | |
688 | } | |
1d4db00a | 689 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 690 | tracing_reset_online_cpus(tr); |
86fa2f60 | 691 | |
60a11774 SR |
692 | printk(KERN_CONT "PASSED\n"); |
693 | } | |
694 | #endif | |
695 | ||
bc0c38d1 SR |
696 | type->next = trace_types; |
697 | trace_types = type; | |
60a11774 | 698 | |
bc0c38d1 | 699 | out: |
8e1b82e0 | 700 | tracing_selftest_running = false; |
bc0c38d1 SR |
701 | mutex_unlock(&trace_types_lock); |
702 | ||
dac74940 SR |
703 | if (ret || !default_bootup_tracer) |
704 | goto out_unlock; | |
705 | ||
ee6c2c1b | 706 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
707 | goto out_unlock; |
708 | ||
709 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
710 | /* Do we want this tracer to start on bootup? */ | |
711 | tracing_set_tracer(type->name); | |
712 | default_bootup_tracer = NULL; | |
713 | /* disable other selftests, since this will break it. */ | |
714 | tracing_selftest_disabled = 1; | |
b2821ae6 | 715 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
716 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
717 | type->name); | |
b2821ae6 | 718 | #endif |
b2821ae6 | 719 | |
dac74940 | 720 | out_unlock: |
b2821ae6 | 721 | lock_kernel(); |
bc0c38d1 SR |
722 | return ret; |
723 | } | |
724 | ||
725 | void unregister_tracer(struct tracer *type) | |
726 | { | |
727 | struct tracer **t; | |
bc0c38d1 SR |
728 | |
729 | mutex_lock(&trace_types_lock); | |
730 | for (t = &trace_types; *t; t = &(*t)->next) { | |
731 | if (*t == type) | |
732 | goto found; | |
733 | } | |
ee6c2c1b | 734 | pr_info("Tracer %s not registered\n", type->name); |
bc0c38d1 SR |
735 | goto out; |
736 | ||
737 | found: | |
738 | *t = (*t)->next; | |
b5db03c4 ACM |
739 | |
740 | if (type == current_trace && tracer_enabled) { | |
741 | tracer_enabled = 0; | |
742 | tracing_stop(); | |
743 | if (current_trace->stop) | |
744 | current_trace->stop(&global_trace); | |
745 | current_trace = &nop_trace; | |
746 | } | |
ee6c2c1b | 747 | out: |
bc0c38d1 SR |
748 | mutex_unlock(&trace_types_lock); |
749 | } | |
750 | ||
f633903a | 751 | static void __tracing_reset(struct trace_array *tr, int cpu) |
bc0c38d1 | 752 | { |
d769041f | 753 | ftrace_disable_cpu(); |
3928a8a2 | 754 | ring_buffer_reset_cpu(tr->buffer, cpu); |
d769041f | 755 | ftrace_enable_cpu(); |
bc0c38d1 SR |
756 | } |
757 | ||
f633903a SR |
758 | void tracing_reset(struct trace_array *tr, int cpu) |
759 | { | |
760 | struct ring_buffer *buffer = tr->buffer; | |
761 | ||
762 | ring_buffer_record_disable(buffer); | |
763 | ||
764 | /* Make sure all commits have finished */ | |
765 | synchronize_sched(); | |
766 | __tracing_reset(tr, cpu); | |
767 | ||
768 | ring_buffer_record_enable(buffer); | |
769 | } | |
770 | ||
213cc060 PE |
771 | void tracing_reset_online_cpus(struct trace_array *tr) |
772 | { | |
621968cd | 773 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
774 | int cpu; |
775 | ||
621968cd SR |
776 | ring_buffer_record_disable(buffer); |
777 | ||
778 | /* Make sure all commits have finished */ | |
779 | synchronize_sched(); | |
780 | ||
213cc060 PE |
781 | tr->time_start = ftrace_now(tr->cpu); |
782 | ||
783 | for_each_online_cpu(cpu) | |
f633903a | 784 | __tracing_reset(tr, cpu); |
621968cd SR |
785 | |
786 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
787 | } |
788 | ||
9456f0fa SR |
789 | void tracing_reset_current(int cpu) |
790 | { | |
791 | tracing_reset(&global_trace, cpu); | |
792 | } | |
793 | ||
794 | void tracing_reset_current_online_cpus(void) | |
795 | { | |
796 | tracing_reset_online_cpus(&global_trace); | |
797 | } | |
798 | ||
bc0c38d1 | 799 | #define SAVED_CMDLINES 128 |
2c7eea4c | 800 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
801 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
802 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
803 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
804 | static int cmdline_idx; | |
efed792d | 805 | static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; |
25b0b44a | 806 | |
25b0b44a | 807 | /* temporary disable recording */ |
4fd27358 | 808 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
809 | |
810 | static void trace_init_cmdlines(void) | |
811 | { | |
2c7eea4c TG |
812 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
813 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
814 | cmdline_idx = 0; |
815 | } | |
816 | ||
b5130b1e CE |
817 | int is_tracing_stopped(void) |
818 | { | |
819 | return trace_stop_count; | |
820 | } | |
821 | ||
69bb54ec SR |
822 | /** |
823 | * ftrace_off_permanent - disable all ftrace code permanently | |
824 | * | |
825 | * This should only be called when a serious anomally has | |
826 | * been detected. This will turn off the function tracing, | |
827 | * ring buffers, and other tracing utilites. It takes no | |
828 | * locks and can be called from any context. | |
829 | */ | |
830 | void ftrace_off_permanent(void) | |
831 | { | |
832 | tracing_disabled = 1; | |
833 | ftrace_stop(); | |
834 | tracing_off_permanent(); | |
835 | } | |
836 | ||
0f048701 SR |
837 | /** |
838 | * tracing_start - quick start of the tracer | |
839 | * | |
840 | * If tracing is enabled but was stopped by tracing_stop, | |
841 | * this will start the tracer back up. | |
842 | */ | |
843 | void tracing_start(void) | |
844 | { | |
845 | struct ring_buffer *buffer; | |
846 | unsigned long flags; | |
847 | ||
848 | if (tracing_disabled) | |
849 | return; | |
850 | ||
851 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
852 | if (--trace_stop_count) { |
853 | if (trace_stop_count < 0) { | |
854 | /* Someone screwed up their debugging */ | |
855 | WARN_ON_ONCE(1); | |
856 | trace_stop_count = 0; | |
857 | } | |
0f048701 SR |
858 | goto out; |
859 | } | |
860 | ||
861 | ||
862 | buffer = global_trace.buffer; | |
863 | if (buffer) | |
864 | ring_buffer_record_enable(buffer); | |
865 | ||
866 | buffer = max_tr.buffer; | |
867 | if (buffer) | |
868 | ring_buffer_record_enable(buffer); | |
869 | ||
870 | ftrace_start(); | |
871 | out: | |
872 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
873 | } | |
874 | ||
875 | /** | |
876 | * tracing_stop - quick stop of the tracer | |
877 | * | |
878 | * Light weight way to stop tracing. Use in conjunction with | |
879 | * tracing_start. | |
880 | */ | |
881 | void tracing_stop(void) | |
882 | { | |
883 | struct ring_buffer *buffer; | |
884 | unsigned long flags; | |
885 | ||
886 | ftrace_stop(); | |
887 | spin_lock_irqsave(&tracing_start_lock, flags); | |
888 | if (trace_stop_count++) | |
889 | goto out; | |
890 | ||
891 | buffer = global_trace.buffer; | |
892 | if (buffer) | |
893 | ring_buffer_record_disable(buffer); | |
894 | ||
895 | buffer = max_tr.buffer; | |
896 | if (buffer) | |
897 | ring_buffer_record_disable(buffer); | |
898 | ||
899 | out: | |
900 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
901 | } | |
902 | ||
e309b41d | 903 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 904 | |
e309b41d | 905 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 906 | { |
a635cf04 | 907 | unsigned pid, idx; |
bc0c38d1 SR |
908 | |
909 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
910 | return; | |
911 | ||
912 | /* | |
913 | * It's not the end of the world if we don't get | |
914 | * the lock, but we also don't want to spin | |
915 | * nor do we want to disable interrupts, | |
916 | * so if we miss here, then better luck next time. | |
917 | */ | |
efed792d | 918 | if (!__raw_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
919 | return; |
920 | ||
921 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 922 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
923 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
924 | ||
a635cf04 CE |
925 | /* |
926 | * Check whether the cmdline buffer at idx has a pid | |
927 | * mapped. We are going to overwrite that entry so we | |
928 | * need to clear the map_pid_to_cmdline. Otherwise we | |
929 | * would read the new comm for the old pid. | |
930 | */ | |
931 | pid = map_cmdline_to_pid[idx]; | |
932 | if (pid != NO_CMDLINE_MAP) | |
933 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 934 | |
a635cf04 | 935 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
936 | map_pid_to_cmdline[tsk->pid] = idx; |
937 | ||
938 | cmdline_idx = idx; | |
939 | } | |
940 | ||
941 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
942 | ||
efed792d | 943 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
944 | } |
945 | ||
4ca53085 | 946 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 947 | { |
bc0c38d1 SR |
948 | unsigned map; |
949 | ||
4ca53085 SR |
950 | if (!pid) { |
951 | strcpy(comm, "<idle>"); | |
952 | return; | |
953 | } | |
bc0c38d1 | 954 | |
4ca53085 SR |
955 | if (pid > PID_MAX_DEFAULT) { |
956 | strcpy(comm, "<...>"); | |
957 | return; | |
958 | } | |
bc0c38d1 | 959 | |
5b6045a9 | 960 | preempt_disable(); |
4ca53085 | 961 | __raw_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 962 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
963 | if (map != NO_CMDLINE_MAP) |
964 | strcpy(comm, saved_cmdlines[map]); | |
965 | else | |
966 | strcpy(comm, "<...>"); | |
bc0c38d1 | 967 | |
4ca53085 | 968 | __raw_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 969 | preempt_enable(); |
bc0c38d1 SR |
970 | } |
971 | ||
e309b41d | 972 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 973 | { |
18aecd36 TG |
974 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
975 | !tracing_is_on()) | |
bc0c38d1 SR |
976 | return; |
977 | ||
978 | trace_save_cmdline(tsk); | |
979 | } | |
980 | ||
45dcd8b8 | 981 | void |
38697053 SR |
982 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
983 | int pc) | |
bc0c38d1 SR |
984 | { |
985 | struct task_struct *tsk = current; | |
bc0c38d1 | 986 | |
777e208d SR |
987 | entry->preempt_count = pc & 0xff; |
988 | entry->pid = (tsk) ? tsk->pid : 0; | |
637e7e86 | 989 | entry->lock_depth = (tsk) ? tsk->lock_depth : 0; |
777e208d | 990 | entry->flags = |
9244489a | 991 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 992 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
993 | #else |
994 | TRACE_FLAG_IRQS_NOSUPPORT | | |
995 | #endif | |
bc0c38d1 SR |
996 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
997 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
998 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
999 | } | |
f413cdb8 | 1000 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1001 | |
e77405ad SR |
1002 | struct ring_buffer_event * |
1003 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1004 | int type, | |
1005 | unsigned long len, | |
1006 | unsigned long flags, int pc) | |
51a763dd ACM |
1007 | { |
1008 | struct ring_buffer_event *event; | |
1009 | ||
e77405ad | 1010 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1011 | if (event != NULL) { |
1012 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1013 | ||
1014 | tracing_generic_entry_update(ent, flags, pc); | |
1015 | ent->type = type; | |
1016 | } | |
1017 | ||
1018 | return event; | |
1019 | } | |
51a763dd | 1020 | |
e77405ad SR |
1021 | static inline void |
1022 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1023 | struct ring_buffer_event *event, | |
1024 | unsigned long flags, int pc, | |
1025 | int wake) | |
51a763dd | 1026 | { |
e77405ad | 1027 | ring_buffer_unlock_commit(buffer, event); |
51a763dd | 1028 | |
e77405ad SR |
1029 | ftrace_trace_stack(buffer, flags, 6, pc); |
1030 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1031 | |
1032 | if (wake) | |
1033 | trace_wake_up(); | |
1034 | } | |
1035 | ||
e77405ad SR |
1036 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1037 | struct ring_buffer_event *event, | |
1038 | unsigned long flags, int pc) | |
07edf712 | 1039 | { |
e77405ad | 1040 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
51a763dd ACM |
1041 | } |
1042 | ||
ef5580d0 | 1043 | struct ring_buffer_event * |
e77405ad SR |
1044 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1045 | int type, unsigned long len, | |
ef5580d0 SR |
1046 | unsigned long flags, int pc) |
1047 | { | |
e77405ad SR |
1048 | *current_rb = global_trace.buffer; |
1049 | return trace_buffer_lock_reserve(*current_rb, | |
ef5580d0 SR |
1050 | type, len, flags, pc); |
1051 | } | |
94487d6d | 1052 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1053 | |
e77405ad SR |
1054 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1055 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1056 | unsigned long flags, int pc) |
1057 | { | |
e77405ad | 1058 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
07edf712 | 1059 | } |
94487d6d | 1060 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1061 | |
e77405ad SR |
1062 | void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer, |
1063 | struct ring_buffer_event *event, | |
1064 | unsigned long flags, int pc) | |
07edf712 | 1065 | { |
e77405ad | 1066 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 0); |
77d9f465 | 1067 | } |
94487d6d | 1068 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 | 1069 | |
e77405ad SR |
1070 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1071 | struct ring_buffer_event *event) | |
77d9f465 | 1072 | { |
e77405ad | 1073 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1074 | } |
12acd473 | 1075 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1076 | |
e309b41d | 1077 | void |
7be42151 | 1078 | trace_function(struct trace_array *tr, |
38697053 SR |
1079 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1080 | int pc) | |
bc0c38d1 | 1081 | { |
e1112b4d | 1082 | struct ftrace_event_call *call = &event_function; |
e77405ad | 1083 | struct ring_buffer *buffer = tr->buffer; |
3928a8a2 | 1084 | struct ring_buffer_event *event; |
777e208d | 1085 | struct ftrace_entry *entry; |
bc0c38d1 | 1086 | |
d769041f | 1087 | /* If we are reading the ring buffer, don't trace */ |
9288f99a | 1088 | if (unlikely(__this_cpu_read(per_cpu_var(ftrace_cpu_disabled)))) |
d769041f SR |
1089 | return; |
1090 | ||
e77405ad | 1091 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1092 | flags, pc); |
3928a8a2 SR |
1093 | if (!event) |
1094 | return; | |
1095 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1096 | entry->ip = ip; |
1097 | entry->parent_ip = parent_ip; | |
e1112b4d | 1098 | |
e77405ad SR |
1099 | if (!filter_check_discard(call, entry, buffer, event)) |
1100 | ring_buffer_unlock_commit(buffer, event); | |
bc0c38d1 SR |
1101 | } |
1102 | ||
e309b41d | 1103 | void |
2e0f5761 | 1104 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1105 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1106 | int pc) | |
2e0f5761 IM |
1107 | { |
1108 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1109 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1110 | } |
1111 | ||
c0a0d0d3 | 1112 | #ifdef CONFIG_STACKTRACE |
e77405ad | 1113 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 SR |
1114 | unsigned long flags, |
1115 | int skip, int pc) | |
86387f7e | 1116 | { |
e1112b4d | 1117 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1118 | struct ring_buffer_event *event; |
777e208d | 1119 | struct stack_entry *entry; |
86387f7e IM |
1120 | struct stack_trace trace; |
1121 | ||
e77405ad | 1122 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
51a763dd | 1123 | sizeof(*entry), flags, pc); |
3928a8a2 SR |
1124 | if (!event) |
1125 | return; | |
1126 | entry = ring_buffer_event_data(event); | |
777e208d | 1127 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
1128 | |
1129 | trace.nr_entries = 0; | |
1130 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1131 | trace.skip = skip; | |
777e208d | 1132 | trace.entries = entry->caller; |
86387f7e IM |
1133 | |
1134 | save_stack_trace(&trace); | |
e77405ad SR |
1135 | if (!filter_check_discard(call, entry, buffer, event)) |
1136 | ring_buffer_unlock_commit(buffer, event); | |
f0a920d5 IM |
1137 | } |
1138 | ||
e77405ad SR |
1139 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1140 | int skip, int pc) | |
53614991 SR |
1141 | { |
1142 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1143 | return; | |
1144 | ||
e77405ad | 1145 | __ftrace_trace_stack(buffer, flags, skip, pc); |
53614991 SR |
1146 | } |
1147 | ||
c0a0d0d3 FW |
1148 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1149 | int pc) | |
38697053 | 1150 | { |
e77405ad | 1151 | __ftrace_trace_stack(tr->buffer, flags, skip, pc); |
38697053 SR |
1152 | } |
1153 | ||
e77405ad SR |
1154 | void |
1155 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1156 | { |
e1112b4d | 1157 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1158 | struct ring_buffer_event *event; |
02b67518 TE |
1159 | struct userstack_entry *entry; |
1160 | struct stack_trace trace; | |
02b67518 TE |
1161 | |
1162 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1163 | return; | |
1164 | ||
e77405ad | 1165 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1166 | sizeof(*entry), flags, pc); |
02b67518 TE |
1167 | if (!event) |
1168 | return; | |
1169 | entry = ring_buffer_event_data(event); | |
02b67518 | 1170 | |
48659d31 | 1171 | entry->tgid = current->tgid; |
02b67518 TE |
1172 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1173 | ||
1174 | trace.nr_entries = 0; | |
1175 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1176 | trace.skip = 0; | |
1177 | trace.entries = entry->caller; | |
1178 | ||
1179 | save_stack_trace_user(&trace); | |
e77405ad SR |
1180 | if (!filter_check_discard(call, entry, buffer, event)) |
1181 | ring_buffer_unlock_commit(buffer, event); | |
02b67518 TE |
1182 | } |
1183 | ||
4fd27358 HE |
1184 | #ifdef UNUSED |
1185 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1186 | { |
7be42151 | 1187 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1188 | } |
4fd27358 | 1189 | #endif /* UNUSED */ |
02b67518 | 1190 | |
c0a0d0d3 FW |
1191 | #endif /* CONFIG_STACKTRACE */ |
1192 | ||
38697053 | 1193 | static void |
7be42151 | 1194 | ftrace_trace_special(void *__tr, |
38697053 SR |
1195 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1196 | int pc) | |
a4feb834 | 1197 | { |
60ba7702 | 1198 | struct ftrace_event_call *call = &event_special; |
3928a8a2 | 1199 | struct ring_buffer_event *event; |
a4feb834 | 1200 | struct trace_array *tr = __tr; |
e77405ad | 1201 | struct ring_buffer *buffer = tr->buffer; |
777e208d | 1202 | struct special_entry *entry; |
a4feb834 | 1203 | |
e77405ad | 1204 | event = trace_buffer_lock_reserve(buffer, TRACE_SPECIAL, |
51a763dd | 1205 | sizeof(*entry), 0, pc); |
3928a8a2 SR |
1206 | if (!event) |
1207 | return; | |
1208 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1209 | entry->arg1 = arg1; |
1210 | entry->arg2 = arg2; | |
1211 | entry->arg3 = arg3; | |
60ba7702 SR |
1212 | |
1213 | if (!filter_check_discard(call, entry, buffer, event)) | |
1214 | trace_buffer_unlock_commit(buffer, event, 0, pc); | |
a4feb834 IM |
1215 | } |
1216 | ||
38697053 SR |
1217 | void |
1218 | __trace_special(void *__tr, void *__data, | |
1219 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1220 | { | |
7be42151 | 1221 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1222 | } |
1223 | ||
4902f884 SR |
1224 | void |
1225 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1226 | { | |
1227 | struct trace_array *tr = &global_trace; | |
1228 | struct trace_array_cpu *data; | |
5aa1ba6a | 1229 | unsigned long flags; |
4902f884 | 1230 | int cpu; |
38697053 | 1231 | int pc; |
4902f884 | 1232 | |
c76f0694 | 1233 | if (tracing_disabled) |
4902f884 SR |
1234 | return; |
1235 | ||
38697053 | 1236 | pc = preempt_count(); |
5aa1ba6a | 1237 | local_irq_save(flags); |
4902f884 SR |
1238 | cpu = raw_smp_processor_id(); |
1239 | data = tr->data[cpu]; | |
4902f884 | 1240 | |
5aa1ba6a | 1241 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1242 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1243 | |
5aa1ba6a SR |
1244 | atomic_dec(&data->disabled); |
1245 | local_irq_restore(flags); | |
4902f884 SR |
1246 | } |
1247 | ||
769b0441 | 1248 | /** |
48ead020 | 1249 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1250 | * |
1251 | */ | |
40ce74f1 | 1252 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1253 | { |
80370cb7 SR |
1254 | static raw_spinlock_t trace_buf_lock = |
1255 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
769b0441 FW |
1256 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1257 | ||
e1112b4d | 1258 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1259 | struct ring_buffer_event *event; |
e77405ad | 1260 | struct ring_buffer *buffer; |
769b0441 FW |
1261 | struct trace_array *tr = &global_trace; |
1262 | struct trace_array_cpu *data; | |
48ead020 | 1263 | struct bprint_entry *entry; |
769b0441 | 1264 | unsigned long flags; |
3189cdb3 | 1265 | int disable; |
769b0441 FW |
1266 | int resched; |
1267 | int cpu, len = 0, size, pc; | |
1268 | ||
1269 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1270 | return 0; | |
1271 | ||
1272 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1273 | pause_graph_tracing(); | |
1274 | ||
1275 | pc = preempt_count(); | |
1276 | resched = ftrace_preempt_disable(); | |
1277 | cpu = raw_smp_processor_id(); | |
1278 | data = tr->data[cpu]; | |
1279 | ||
3189cdb3 SR |
1280 | disable = atomic_inc_return(&data->disabled); |
1281 | if (unlikely(disable != 1)) | |
769b0441 FW |
1282 | goto out; |
1283 | ||
80370cb7 SR |
1284 | /* Lockdep uses trace_printk for lock tracing */ |
1285 | local_irq_save(flags); | |
1286 | __raw_spin_lock(&trace_buf_lock); | |
769b0441 FW |
1287 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1288 | ||
1289 | if (len > TRACE_BUF_SIZE || len < 0) | |
1290 | goto out_unlock; | |
1291 | ||
1292 | size = sizeof(*entry) + sizeof(u32) * len; | |
e77405ad SR |
1293 | buffer = tr->buffer; |
1294 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, | |
1295 | flags, pc); | |
769b0441 FW |
1296 | if (!event) |
1297 | goto out_unlock; | |
1298 | entry = ring_buffer_event_data(event); | |
1299 | entry->ip = ip; | |
769b0441 FW |
1300 | entry->fmt = fmt; |
1301 | ||
1302 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
e77405ad SR |
1303 | if (!filter_check_discard(call, entry, buffer, event)) |
1304 | ring_buffer_unlock_commit(buffer, event); | |
769b0441 FW |
1305 | |
1306 | out_unlock: | |
80370cb7 SR |
1307 | __raw_spin_unlock(&trace_buf_lock); |
1308 | local_irq_restore(flags); | |
769b0441 FW |
1309 | |
1310 | out: | |
3189cdb3 | 1311 | atomic_dec_return(&data->disabled); |
769b0441 FW |
1312 | ftrace_preempt_enable(resched); |
1313 | unpause_graph_tracing(); | |
1314 | ||
1315 | return len; | |
1316 | } | |
48ead020 FW |
1317 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1318 | ||
659372d3 SR |
1319 | int trace_array_printk(struct trace_array *tr, |
1320 | unsigned long ip, const char *fmt, ...) | |
1321 | { | |
1322 | int ret; | |
1323 | va_list ap; | |
1324 | ||
1325 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1326 | return 0; | |
1327 | ||
1328 | va_start(ap, fmt); | |
1329 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
1330 | va_end(ap); | |
1331 | return ret; | |
1332 | } | |
1333 | ||
1334 | int trace_array_vprintk(struct trace_array *tr, | |
1335 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 FW |
1336 | { |
1337 | static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; | |
1338 | static char trace_buf[TRACE_BUF_SIZE]; | |
1339 | ||
e1112b4d | 1340 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1341 | struct ring_buffer_event *event; |
e77405ad | 1342 | struct ring_buffer *buffer; |
48ead020 FW |
1343 | struct trace_array_cpu *data; |
1344 | int cpu, len = 0, size, pc; | |
1345 | struct print_entry *entry; | |
1346 | unsigned long irq_flags; | |
3189cdb3 | 1347 | int disable; |
48ead020 FW |
1348 | |
1349 | if (tracing_disabled || tracing_selftest_running) | |
1350 | return 0; | |
1351 | ||
1352 | pc = preempt_count(); | |
1353 | preempt_disable_notrace(); | |
1354 | cpu = raw_smp_processor_id(); | |
1355 | data = tr->data[cpu]; | |
1356 | ||
3189cdb3 SR |
1357 | disable = atomic_inc_return(&data->disabled); |
1358 | if (unlikely(disable != 1)) | |
48ead020 FW |
1359 | goto out; |
1360 | ||
1361 | pause_graph_tracing(); | |
1362 | raw_local_irq_save(irq_flags); | |
1363 | __raw_spin_lock(&trace_buf_lock); | |
1364 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); | |
1365 | ||
1366 | len = min(len, TRACE_BUF_SIZE-1); | |
1367 | trace_buf[len] = 0; | |
1368 | ||
1369 | size = sizeof(*entry) + len + 1; | |
e77405ad SR |
1370 | buffer = tr->buffer; |
1371 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
1372 | irq_flags, pc); | |
48ead020 FW |
1373 | if (!event) |
1374 | goto out_unlock; | |
1375 | entry = ring_buffer_event_data(event); | |
1376 | entry->ip = ip; | |
48ead020 FW |
1377 | |
1378 | memcpy(&entry->buf, trace_buf, len); | |
1379 | entry->buf[len] = 0; | |
e77405ad SR |
1380 | if (!filter_check_discard(call, entry, buffer, event)) |
1381 | ring_buffer_unlock_commit(buffer, event); | |
48ead020 FW |
1382 | |
1383 | out_unlock: | |
1384 | __raw_spin_unlock(&trace_buf_lock); | |
1385 | raw_local_irq_restore(irq_flags); | |
1386 | unpause_graph_tracing(); | |
1387 | out: | |
3189cdb3 | 1388 | atomic_dec_return(&data->disabled); |
48ead020 FW |
1389 | preempt_enable_notrace(); |
1390 | ||
1391 | return len; | |
1392 | } | |
659372d3 SR |
1393 | |
1394 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) | |
1395 | { | |
1396 | return trace_array_printk(&global_trace, ip, fmt, args); | |
1397 | } | |
769b0441 FW |
1398 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1399 | ||
bc0c38d1 SR |
1400 | enum trace_file_type { |
1401 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1402 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1403 | }; |
1404 | ||
e2ac8ef5 | 1405 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1406 | { |
d769041f SR |
1407 | /* Don't allow ftrace to trace into the ring buffers */ |
1408 | ftrace_disable_cpu(); | |
1409 | ||
5a90f577 | 1410 | iter->idx++; |
d769041f SR |
1411 | if (iter->buffer_iter[iter->cpu]) |
1412 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1413 | ||
1414 | ftrace_enable_cpu(); | |
5a90f577 SR |
1415 | } |
1416 | ||
e309b41d | 1417 | static struct trace_entry * |
3928a8a2 | 1418 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1419 | { |
3928a8a2 SR |
1420 | struct ring_buffer_event *event; |
1421 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1422 | |
d769041f SR |
1423 | /* Don't allow ftrace to trace into the ring buffers */ |
1424 | ftrace_disable_cpu(); | |
1425 | ||
1426 | if (buf_iter) | |
1427 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1428 | else | |
1429 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1430 | ||
1431 | ftrace_enable_cpu(); | |
1432 | ||
3928a8a2 | 1433 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1434 | } |
d769041f | 1435 | |
dd0e545f | 1436 | static struct trace_entry * |
3928a8a2 | 1437 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1438 | { |
3928a8a2 | 1439 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1440 | struct trace_entry *ent, *next = NULL; |
b04cc6b1 | 1441 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1442 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1443 | int next_cpu = -1; |
1444 | int cpu; | |
1445 | ||
b04cc6b1 FW |
1446 | /* |
1447 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1448 | * all cpu and peek directly. | |
1449 | */ | |
1450 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1451 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1452 | return NULL; | |
1453 | ent = peek_next_entry(iter, cpu_file, ent_ts); | |
1454 | if (ent_cpu) | |
1455 | *ent_cpu = cpu_file; | |
1456 | ||
1457 | return ent; | |
1458 | } | |
1459 | ||
ab46428c | 1460 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1461 | |
3928a8a2 SR |
1462 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1463 | continue; | |
dd0e545f | 1464 | |
3928a8a2 | 1465 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1466 | |
cdd31cd2 IM |
1467 | /* |
1468 | * Pick the entry with the smallest timestamp: | |
1469 | */ | |
3928a8a2 | 1470 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1471 | next = ent; |
1472 | next_cpu = cpu; | |
3928a8a2 | 1473 | next_ts = ts; |
bc0c38d1 SR |
1474 | } |
1475 | } | |
1476 | ||
1477 | if (ent_cpu) | |
1478 | *ent_cpu = next_cpu; | |
1479 | ||
3928a8a2 SR |
1480 | if (ent_ts) |
1481 | *ent_ts = next_ts; | |
1482 | ||
bc0c38d1 SR |
1483 | return next; |
1484 | } | |
1485 | ||
dd0e545f | 1486 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1487 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1488 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1489 | { |
3928a8a2 | 1490 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1491 | } |
1492 | ||
1493 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1494 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1495 | { | |
3928a8a2 | 1496 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1497 | |
3928a8a2 | 1498 | if (iter->ent) |
e2ac8ef5 | 1499 | trace_iterator_increment(iter); |
dd0e545f | 1500 | |
3928a8a2 | 1501 | return iter->ent ? iter : NULL; |
b3806b43 | 1502 | } |
bc0c38d1 | 1503 | |
e309b41d | 1504 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1505 | { |
d769041f SR |
1506 | /* Don't allow ftrace to trace into the ring buffers */ |
1507 | ftrace_disable_cpu(); | |
3928a8a2 | 1508 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1509 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1510 | } |
1511 | ||
e309b41d | 1512 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1513 | { |
1514 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1515 | int i = (int)*pos; |
4e3c3333 | 1516 | void *ent; |
bc0c38d1 SR |
1517 | |
1518 | (*pos)++; | |
1519 | ||
1520 | /* can't go backwards */ | |
1521 | if (iter->idx > i) | |
1522 | return NULL; | |
1523 | ||
1524 | if (iter->idx < 0) | |
1525 | ent = find_next_entry_inc(iter); | |
1526 | else | |
1527 | ent = iter; | |
1528 | ||
1529 | while (ent && iter->idx < i) | |
1530 | ent = find_next_entry_inc(iter); | |
1531 | ||
1532 | iter->pos = *pos; | |
1533 | ||
bc0c38d1 SR |
1534 | return ent; |
1535 | } | |
1536 | ||
2f26ebd5 SR |
1537 | static void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
1538 | { | |
1539 | struct trace_array *tr = iter->tr; | |
1540 | struct ring_buffer_event *event; | |
1541 | struct ring_buffer_iter *buf_iter; | |
1542 | unsigned long entries = 0; | |
1543 | u64 ts; | |
1544 | ||
1545 | tr->data[cpu]->skipped_entries = 0; | |
1546 | ||
1547 | if (!iter->buffer_iter[cpu]) | |
1548 | return; | |
1549 | ||
1550 | buf_iter = iter->buffer_iter[cpu]; | |
1551 | ring_buffer_iter_reset(buf_iter); | |
1552 | ||
1553 | /* | |
1554 | * We could have the case with the max latency tracers | |
1555 | * that a reset never took place on a cpu. This is evident | |
1556 | * by the timestamp being before the start of the buffer. | |
1557 | */ | |
1558 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
1559 | if (ts >= iter->tr->time_start) | |
1560 | break; | |
1561 | entries++; | |
1562 | ring_buffer_read(buf_iter, NULL); | |
1563 | } | |
1564 | ||
1565 | tr->data[cpu]->skipped_entries = entries; | |
1566 | } | |
1567 | ||
d7350c3f FW |
1568 | /* |
1569 | * No necessary locking here. The worst thing which can | |
1570 | * happen is loosing events consumed at the same time | |
1571 | * by a trace_pipe reader. | |
1572 | * Other than that, we don't risk to crash the ring buffer | |
1573 | * because it serializes the readers. | |
1574 | * | |
1575 | * The current tracer is copied to avoid a global locking | |
1576 | * all around. | |
1577 | */ | |
bc0c38d1 SR |
1578 | static void *s_start(struct seq_file *m, loff_t *pos) |
1579 | { | |
1580 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1581 | static struct tracer *old_tracer; |
b04cc6b1 | 1582 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1583 | void *p = NULL; |
1584 | loff_t l = 0; | |
3928a8a2 | 1585 | int cpu; |
bc0c38d1 | 1586 | |
d7350c3f | 1587 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1588 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1589 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1590 | old_tracer = current_trace; | |
1591 | *iter->trace = *current_trace; | |
d15f57f2 | 1592 | } |
d7350c3f | 1593 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1594 | |
1595 | atomic_inc(&trace_record_cmdline_disabled); | |
1596 | ||
bc0c38d1 SR |
1597 | if (*pos != iter->pos) { |
1598 | iter->ent = NULL; | |
1599 | iter->cpu = 0; | |
1600 | iter->idx = -1; | |
1601 | ||
d769041f SR |
1602 | ftrace_disable_cpu(); |
1603 | ||
b04cc6b1 FW |
1604 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1605 | for_each_tracing_cpu(cpu) | |
2f26ebd5 | 1606 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 1607 | } else |
2f26ebd5 | 1608 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 1609 | |
d769041f SR |
1610 | ftrace_enable_cpu(); |
1611 | ||
bc0c38d1 SR |
1612 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1613 | ; | |
1614 | ||
1615 | } else { | |
4c11d7ae | 1616 | l = *pos - 1; |
bc0c38d1 SR |
1617 | p = s_next(m, p, &l); |
1618 | } | |
1619 | ||
4f535968 | 1620 | trace_event_read_lock(); |
bc0c38d1 SR |
1621 | return p; |
1622 | } | |
1623 | ||
1624 | static void s_stop(struct seq_file *m, void *p) | |
1625 | { | |
bc0c38d1 | 1626 | atomic_dec(&trace_record_cmdline_disabled); |
4f535968 | 1627 | trace_event_read_unlock(); |
bc0c38d1 SR |
1628 | } |
1629 | ||
e309b41d | 1630 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1631 | { |
a6168353 ME |
1632 | seq_puts(m, "# _------=> CPU# \n"); |
1633 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1634 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1635 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1636 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
637e7e86 SR |
1637 | seq_puts(m, "# |||| /_--=> lock-depth \n"); |
1638 | seq_puts(m, "# |||||/ delay \n"); | |
1639 | seq_puts(m, "# cmd pid |||||| time | caller \n"); | |
1640 | seq_puts(m, "# \\ / |||||| \\ | / \n"); | |
bc0c38d1 SR |
1641 | } |
1642 | ||
e309b41d | 1643 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1644 | { |
a6168353 ME |
1645 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1646 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1647 | } |
1648 | ||
1649 | ||
e309b41d | 1650 | static void |
bc0c38d1 SR |
1651 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1652 | { | |
1653 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1654 | struct trace_array *tr = iter->tr; | |
1655 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1656 | struct tracer *type = current_trace; | |
2f26ebd5 SR |
1657 | unsigned long entries = 0; |
1658 | unsigned long total = 0; | |
1659 | unsigned long count; | |
bc0c38d1 | 1660 | const char *name = "preemption"; |
2f26ebd5 | 1661 | int cpu; |
bc0c38d1 SR |
1662 | |
1663 | if (type) | |
1664 | name = type->name; | |
1665 | ||
2f26ebd5 SR |
1666 | |
1667 | for_each_tracing_cpu(cpu) { | |
1668 | count = ring_buffer_entries_cpu(tr->buffer, cpu); | |
1669 | /* | |
1670 | * If this buffer has skipped entries, then we hold all | |
1671 | * entries for the trace and we need to ignore the | |
1672 | * ones before the time stamp. | |
1673 | */ | |
1674 | if (tr->data[cpu]->skipped_entries) { | |
1675 | count -= tr->data[cpu]->skipped_entries; | |
1676 | /* total is the same as the entries */ | |
1677 | total += count; | |
1678 | } else | |
1679 | total += count + | |
1680 | ring_buffer_overrun_cpu(tr->buffer, cpu); | |
1681 | entries += count; | |
1682 | } | |
bc0c38d1 | 1683 | |
888b55dc | 1684 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1685 | name, UTS_RELEASE); |
888b55dc | 1686 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1687 | "---------------------------------\n"); |
888b55dc | 1688 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1689 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1690 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1691 | entries, |
4c11d7ae | 1692 | total, |
bc0c38d1 SR |
1693 | tr->cpu, |
1694 | #if defined(CONFIG_PREEMPT_NONE) | |
1695 | "server", | |
1696 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1697 | "desktop", | |
b5c21b45 | 1698 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1699 | "preempt", |
1700 | #else | |
1701 | "unknown", | |
1702 | #endif | |
1703 | /* These are reserved for later use */ | |
1704 | 0, 0, 0, 0); | |
1705 | #ifdef CONFIG_SMP | |
1706 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1707 | #else | |
1708 | seq_puts(m, ")\n"); | |
1709 | #endif | |
888b55dc KM |
1710 | seq_puts(m, "# -----------------\n"); |
1711 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1712 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1713 | data->comm, data->pid, data->uid, data->nice, | |
1714 | data->policy, data->rt_priority); | |
888b55dc | 1715 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1716 | |
1717 | if (data->critical_start) { | |
888b55dc | 1718 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1719 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1720 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1721 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1722 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1723 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 1724 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
1725 | } |
1726 | ||
888b55dc | 1727 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1728 | } |
1729 | ||
a309720c SR |
1730 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1731 | { | |
1732 | struct trace_seq *s = &iter->seq; | |
1733 | ||
12ef7d44 SR |
1734 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1735 | return; | |
1736 | ||
1737 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1738 | return; | |
1739 | ||
4462344e | 1740 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1741 | return; |
1742 | ||
2f26ebd5 SR |
1743 | if (iter->tr->data[iter->cpu]->skipped_entries) |
1744 | return; | |
1745 | ||
4462344e | 1746 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1747 | |
1748 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1749 | if (iter->idx > 1) | |
1750 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1751 | iter->cpu); | |
a309720c SR |
1752 | } |
1753 | ||
2c4f035f | 1754 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1755 | { |
214023c3 | 1756 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1757 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1758 | struct trace_entry *entry; |
f633cef0 | 1759 | struct trace_event *event; |
bc0c38d1 | 1760 | |
4e3c3333 | 1761 | entry = iter->ent; |
dd0e545f | 1762 | |
a309720c SR |
1763 | test_cpu_buff_start(iter); |
1764 | ||
c4a8e8be | 1765 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1766 | |
c4a8e8be | 1767 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1768 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1769 | if (!trace_print_lat_context(iter)) | |
1770 | goto partial; | |
1771 | } else { | |
1772 | if (!trace_print_context(iter)) | |
1773 | goto partial; | |
1774 | } | |
c4a8e8be | 1775 | } |
bc0c38d1 | 1776 | |
268ccda0 | 1777 | if (event) |
d9793bd8 ACM |
1778 | return event->trace(iter, sym_flags); |
1779 | ||
1780 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1781 | goto partial; | |
02b67518 | 1782 | |
2c4f035f | 1783 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1784 | partial: |
1785 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1786 | } |
1787 | ||
2c4f035f | 1788 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1789 | { |
1790 | struct trace_seq *s = &iter->seq; | |
1791 | struct trace_entry *entry; | |
f633cef0 | 1792 | struct trace_event *event; |
f9896bf3 IM |
1793 | |
1794 | entry = iter->ent; | |
dd0e545f | 1795 | |
c4a8e8be | 1796 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1797 | if (!trace_seq_printf(s, "%d %d %llu ", |
1798 | entry->pid, iter->cpu, iter->ts)) | |
1799 | goto partial; | |
c4a8e8be | 1800 | } |
f9896bf3 | 1801 | |
f633cef0 | 1802 | event = ftrace_find_event(entry->type); |
268ccda0 | 1803 | if (event) |
d9793bd8 ACM |
1804 | return event->raw(iter, 0); |
1805 | ||
1806 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1807 | goto partial; | |
777e208d | 1808 | |
2c4f035f | 1809 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1810 | partial: |
1811 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1812 | } |
1813 | ||
2c4f035f | 1814 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1815 | { |
1816 | struct trace_seq *s = &iter->seq; | |
1817 | unsigned char newline = '\n'; | |
1818 | struct trace_entry *entry; | |
f633cef0 | 1819 | struct trace_event *event; |
5e3ca0ec IM |
1820 | |
1821 | entry = iter->ent; | |
dd0e545f | 1822 | |
c4a8e8be FW |
1823 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1824 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1825 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1826 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1827 | } | |
5e3ca0ec | 1828 | |
f633cef0 | 1829 | event = ftrace_find_event(entry->type); |
268ccda0 | 1830 | if (event) { |
ae7462b4 | 1831 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1832 | if (ret != TRACE_TYPE_HANDLED) |
1833 | return ret; | |
1834 | } | |
7104f300 | 1835 | |
5e3ca0ec IM |
1836 | SEQ_PUT_FIELD_RET(s, newline); |
1837 | ||
2c4f035f | 1838 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1839 | } |
1840 | ||
2c4f035f | 1841 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1842 | { |
1843 | struct trace_seq *s = &iter->seq; | |
1844 | struct trace_entry *entry; | |
f633cef0 | 1845 | struct trace_event *event; |
cb0f12aa IM |
1846 | |
1847 | entry = iter->ent; | |
dd0e545f | 1848 | |
c4a8e8be FW |
1849 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1850 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1851 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1852 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1853 | } | |
cb0f12aa | 1854 | |
f633cef0 | 1855 | event = ftrace_find_event(entry->type); |
268ccda0 | 1856 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1857 | } |
1858 | ||
bc0c38d1 SR |
1859 | static int trace_empty(struct trace_iterator *iter) |
1860 | { | |
bc0c38d1 SR |
1861 | int cpu; |
1862 | ||
9aba60fe SR |
1863 | /* If we are looking at one CPU buffer, only check that one */ |
1864 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1865 | cpu = iter->cpu_file; | |
1866 | if (iter->buffer_iter[cpu]) { | |
1867 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1868 | return 0; | |
1869 | } else { | |
1870 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1871 | return 0; | |
1872 | } | |
1873 | return 1; | |
1874 | } | |
1875 | ||
ab46428c | 1876 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1877 | if (iter->buffer_iter[cpu]) { |
1878 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1879 | return 0; | |
1880 | } else { | |
1881 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1882 | return 0; | |
1883 | } | |
bc0c38d1 | 1884 | } |
d769041f | 1885 | |
797d3712 | 1886 | return 1; |
bc0c38d1 SR |
1887 | } |
1888 | ||
4f535968 | 1889 | /* Called with trace_event_read_lock() held. */ |
2c4f035f | 1890 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1891 | { |
2c4f035f FW |
1892 | enum print_line_t ret; |
1893 | ||
1894 | if (iter->trace && iter->trace->print_line) { | |
1895 | ret = iter->trace->print_line(iter); | |
1896 | if (ret != TRACE_TYPE_UNHANDLED) | |
1897 | return ret; | |
1898 | } | |
72829bc3 | 1899 | |
48ead020 FW |
1900 | if (iter->ent->type == TRACE_BPRINT && |
1901 | trace_flags & TRACE_ITER_PRINTK && | |
1902 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1903 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 1904 | |
66896a85 FW |
1905 | if (iter->ent->type == TRACE_PRINT && |
1906 | trace_flags & TRACE_ITER_PRINTK && | |
1907 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1908 | return trace_print_printk_msg_only(iter); |
66896a85 | 1909 | |
cb0f12aa IM |
1910 | if (trace_flags & TRACE_ITER_BIN) |
1911 | return print_bin_fmt(iter); | |
1912 | ||
5e3ca0ec IM |
1913 | if (trace_flags & TRACE_ITER_HEX) |
1914 | return print_hex_fmt(iter); | |
1915 | ||
f9896bf3 IM |
1916 | if (trace_flags & TRACE_ITER_RAW) |
1917 | return print_raw_fmt(iter); | |
1918 | ||
f9896bf3 IM |
1919 | return print_trace_fmt(iter); |
1920 | } | |
1921 | ||
bc0c38d1 SR |
1922 | static int s_show(struct seq_file *m, void *v) |
1923 | { | |
1924 | struct trace_iterator *iter = v; | |
1925 | ||
1926 | if (iter->ent == NULL) { | |
1927 | if (iter->tr) { | |
1928 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1929 | seq_puts(m, "#\n"); | |
1930 | } | |
8bba1bf5 MM |
1931 | if (iter->trace && iter->trace->print_header) |
1932 | iter->trace->print_header(m); | |
1933 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
1934 | /* print nothing if the buffers are empty */ |
1935 | if (trace_empty(iter)) | |
1936 | return 0; | |
1937 | print_trace_header(m, iter); | |
1938 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1939 | print_lat_help_header(m); | |
1940 | } else { | |
1941 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1942 | print_func_help_header(m); | |
1943 | } | |
1944 | } else { | |
f9896bf3 | 1945 | print_trace_line(iter); |
214023c3 | 1946 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1947 | } |
1948 | ||
1949 | return 0; | |
1950 | } | |
1951 | ||
88e9d34c | 1952 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
1953 | .start = s_start, |
1954 | .next = s_next, | |
1955 | .stop = s_stop, | |
1956 | .show = s_show, | |
bc0c38d1 SR |
1957 | }; |
1958 | ||
e309b41d | 1959 | static struct trace_iterator * |
85a2f9b4 | 1960 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 1961 | { |
b04cc6b1 | 1962 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 1963 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 1964 | struct trace_iterator *iter; |
3928a8a2 | 1965 | struct seq_file *m; |
85a2f9b4 | 1966 | int cpu, ret; |
bc0c38d1 | 1967 | |
85a2f9b4 SR |
1968 | if (tracing_disabled) |
1969 | return ERR_PTR(-ENODEV); | |
60a11774 | 1970 | |
bc0c38d1 | 1971 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
1972 | if (!iter) |
1973 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 1974 | |
d7350c3f FW |
1975 | /* |
1976 | * We make a copy of the current tracer to avoid concurrent | |
1977 | * changes on it while we are reading. | |
1978 | */ | |
bc0c38d1 | 1979 | mutex_lock(&trace_types_lock); |
d7350c3f | 1980 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 1981 | if (!iter->trace) |
d7350c3f | 1982 | goto fail; |
85a2f9b4 | 1983 | |
d7350c3f FW |
1984 | if (current_trace) |
1985 | *iter->trace = *current_trace; | |
1986 | ||
79f55997 | 1987 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
1988 | goto fail; |
1989 | ||
bc0c38d1 SR |
1990 | if (current_trace && current_trace->print_max) |
1991 | iter->tr = &max_tr; | |
1992 | else | |
b04cc6b1 | 1993 | iter->tr = &global_trace; |
bc0c38d1 | 1994 | iter->pos = -1; |
d7350c3f | 1995 | mutex_init(&iter->mutex); |
b04cc6b1 | 1996 | iter->cpu_file = cpu_file; |
bc0c38d1 | 1997 | |
8bba1bf5 MM |
1998 | /* Notify the tracer early; before we stop tracing. */ |
1999 | if (iter->trace && iter->trace->open) | |
a93751ca | 2000 | iter->trace->open(iter); |
8bba1bf5 | 2001 | |
12ef7d44 SR |
2002 | /* Annotate start of buffers if we had overruns */ |
2003 | if (ring_buffer_overruns(iter->tr->buffer)) | |
2004 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
2005 | ||
2f26ebd5 SR |
2006 | /* stop the trace while dumping */ |
2007 | tracing_stop(); | |
2008 | ||
b04cc6b1 FW |
2009 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
2010 | for_each_tracing_cpu(cpu) { | |
12ef7d44 | 2011 | |
b04cc6b1 FW |
2012 | iter->buffer_iter[cpu] = |
2013 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
2f26ebd5 | 2014 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2015 | } |
2016 | } else { | |
2017 | cpu = iter->cpu_file; | |
3928a8a2 | 2018 | iter->buffer_iter[cpu] = |
b04cc6b1 | 2019 | ring_buffer_read_start(iter->tr->buffer, cpu); |
2f26ebd5 | 2020 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2021 | } |
2022 | ||
85a2f9b4 SR |
2023 | ret = seq_open(file, &tracer_seq_ops); |
2024 | if (ret < 0) { | |
2025 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 2026 | goto fail_buffer; |
85a2f9b4 | 2027 | } |
bc0c38d1 | 2028 | |
3928a8a2 SR |
2029 | m = file->private_data; |
2030 | m->private = iter; | |
bc0c38d1 | 2031 | |
bc0c38d1 SR |
2032 | mutex_unlock(&trace_types_lock); |
2033 | ||
bc0c38d1 | 2034 | return iter; |
3928a8a2 SR |
2035 | |
2036 | fail_buffer: | |
2037 | for_each_tracing_cpu(cpu) { | |
2038 | if (iter->buffer_iter[cpu]) | |
2039 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2040 | } | |
b0dfa978 | 2041 | free_cpumask_var(iter->started); |
2f26ebd5 | 2042 | tracing_start(); |
d7350c3f | 2043 | fail: |
3928a8a2 | 2044 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2045 | kfree(iter->trace); |
0bb943c7 | 2046 | kfree(iter); |
3928a8a2 | 2047 | |
85a2f9b4 | 2048 | return fail_ret; |
bc0c38d1 SR |
2049 | } |
2050 | ||
2051 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2052 | { | |
60a11774 SR |
2053 | if (tracing_disabled) |
2054 | return -ENODEV; | |
2055 | ||
bc0c38d1 SR |
2056 | filp->private_data = inode->i_private; |
2057 | return 0; | |
2058 | } | |
2059 | ||
4fd27358 | 2060 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
2061 | { |
2062 | struct seq_file *m = (struct seq_file *)file->private_data; | |
4acd4d00 | 2063 | struct trace_iterator *iter; |
3928a8a2 | 2064 | int cpu; |
bc0c38d1 | 2065 | |
4acd4d00 SR |
2066 | if (!(file->f_mode & FMODE_READ)) |
2067 | return 0; | |
2068 | ||
2069 | iter = m->private; | |
2070 | ||
bc0c38d1 | 2071 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
2072 | for_each_tracing_cpu(cpu) { |
2073 | if (iter->buffer_iter[cpu]) | |
2074 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2075 | } | |
2076 | ||
bc0c38d1 SR |
2077 | if (iter->trace && iter->trace->close) |
2078 | iter->trace->close(iter); | |
2079 | ||
2080 | /* reenable tracing if it was previously enabled */ | |
9036990d | 2081 | tracing_start(); |
bc0c38d1 SR |
2082 | mutex_unlock(&trace_types_lock); |
2083 | ||
2084 | seq_release(inode, file); | |
d7350c3f | 2085 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2086 | free_cpumask_var(iter->started); |
d7350c3f | 2087 | kfree(iter->trace); |
bc0c38d1 SR |
2088 | kfree(iter); |
2089 | return 0; | |
2090 | } | |
2091 | ||
2092 | static int tracing_open(struct inode *inode, struct file *file) | |
2093 | { | |
85a2f9b4 SR |
2094 | struct trace_iterator *iter; |
2095 | int ret = 0; | |
bc0c38d1 | 2096 | |
4acd4d00 SR |
2097 | /* If this file was open for write, then erase contents */ |
2098 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2099 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 2100 | long cpu = (long) inode->i_private; |
bc0c38d1 | 2101 | |
4acd4d00 SR |
2102 | if (cpu == TRACE_PIPE_ALL_CPU) |
2103 | tracing_reset_online_cpus(&global_trace); | |
2104 | else | |
2105 | tracing_reset(&global_trace, cpu); | |
2106 | } | |
bc0c38d1 | 2107 | |
4acd4d00 SR |
2108 | if (file->f_mode & FMODE_READ) { |
2109 | iter = __tracing_open(inode, file); | |
2110 | if (IS_ERR(iter)) | |
2111 | ret = PTR_ERR(iter); | |
2112 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2113 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2114 | } | |
bc0c38d1 SR |
2115 | return ret; |
2116 | } | |
2117 | ||
e309b41d | 2118 | static void * |
bc0c38d1 SR |
2119 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2120 | { | |
f129e965 | 2121 | struct tracer *t = v; |
bc0c38d1 SR |
2122 | |
2123 | (*pos)++; | |
2124 | ||
2125 | if (t) | |
2126 | t = t->next; | |
2127 | ||
bc0c38d1 SR |
2128 | return t; |
2129 | } | |
2130 | ||
2131 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2132 | { | |
f129e965 | 2133 | struct tracer *t; |
bc0c38d1 SR |
2134 | loff_t l = 0; |
2135 | ||
2136 | mutex_lock(&trace_types_lock); | |
f129e965 | 2137 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2138 | ; |
2139 | ||
2140 | return t; | |
2141 | } | |
2142 | ||
2143 | static void t_stop(struct seq_file *m, void *p) | |
2144 | { | |
2145 | mutex_unlock(&trace_types_lock); | |
2146 | } | |
2147 | ||
2148 | static int t_show(struct seq_file *m, void *v) | |
2149 | { | |
2150 | struct tracer *t = v; | |
2151 | ||
2152 | if (!t) | |
2153 | return 0; | |
2154 | ||
2155 | seq_printf(m, "%s", t->name); | |
2156 | if (t->next) | |
2157 | seq_putc(m, ' '); | |
2158 | else | |
2159 | seq_putc(m, '\n'); | |
2160 | ||
2161 | return 0; | |
2162 | } | |
2163 | ||
88e9d34c | 2164 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
2165 | .start = t_start, |
2166 | .next = t_next, | |
2167 | .stop = t_stop, | |
2168 | .show = t_show, | |
bc0c38d1 SR |
2169 | }; |
2170 | ||
2171 | static int show_traces_open(struct inode *inode, struct file *file) | |
2172 | { | |
60a11774 SR |
2173 | if (tracing_disabled) |
2174 | return -ENODEV; | |
2175 | ||
f129e965 | 2176 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2177 | } |
2178 | ||
4acd4d00 SR |
2179 | static ssize_t |
2180 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2181 | size_t count, loff_t *ppos) | |
2182 | { | |
2183 | return count; | |
2184 | } | |
2185 | ||
5e2336a0 | 2186 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2187 | .open = tracing_open, |
2188 | .read = seq_read, | |
4acd4d00 | 2189 | .write = tracing_write_stub, |
4bf39a94 IM |
2190 | .llseek = seq_lseek, |
2191 | .release = tracing_release, | |
bc0c38d1 SR |
2192 | }; |
2193 | ||
5e2336a0 | 2194 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2195 | .open = show_traces_open, |
2196 | .read = seq_read, | |
2197 | .release = seq_release, | |
2198 | }; | |
2199 | ||
36dfe925 IM |
2200 | /* |
2201 | * Only trace on a CPU if the bitmask is set: | |
2202 | */ | |
9e01c1b7 | 2203 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2204 | |
2205 | /* | |
2206 | * The tracer itself will not take this lock, but still we want | |
2207 | * to provide a consistent cpumask to user-space: | |
2208 | */ | |
2209 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2210 | ||
2211 | /* | |
2212 | * Temporary storage for the character representation of the | |
2213 | * CPU bitmask (and one more byte for the newline): | |
2214 | */ | |
2215 | static char mask_str[NR_CPUS + 1]; | |
2216 | ||
c7078de1 IM |
2217 | static ssize_t |
2218 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2219 | size_t count, loff_t *ppos) | |
2220 | { | |
36dfe925 | 2221 | int len; |
c7078de1 IM |
2222 | |
2223 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2224 | |
9e01c1b7 | 2225 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2226 | if (count - len < 2) { |
2227 | count = -EINVAL; | |
2228 | goto out_err; | |
2229 | } | |
2230 | len += sprintf(mask_str + len, "\n"); | |
2231 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2232 | ||
2233 | out_err: | |
c7078de1 IM |
2234 | mutex_unlock(&tracing_cpumask_update_lock); |
2235 | ||
2236 | return count; | |
2237 | } | |
2238 | ||
2239 | static ssize_t | |
2240 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2241 | size_t count, loff_t *ppos) | |
2242 | { | |
36dfe925 | 2243 | int err, cpu; |
9e01c1b7 RR |
2244 | cpumask_var_t tracing_cpumask_new; |
2245 | ||
2246 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2247 | return -ENOMEM; | |
c7078de1 | 2248 | |
9e01c1b7 | 2249 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2250 | if (err) |
36dfe925 IM |
2251 | goto err_unlock; |
2252 | ||
215368e8 LZ |
2253 | mutex_lock(&tracing_cpumask_update_lock); |
2254 | ||
a5e25883 | 2255 | local_irq_disable(); |
92205c23 | 2256 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 2257 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2258 | /* |
2259 | * Increase/decrease the disabled counter if we are | |
2260 | * about to flip a bit in the cpumask: | |
2261 | */ | |
9e01c1b7 RR |
2262 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2263 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2264 | atomic_inc(&global_trace.data[cpu]->disabled); |
2265 | } | |
9e01c1b7 RR |
2266 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2267 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2268 | atomic_dec(&global_trace.data[cpu]->disabled); |
2269 | } | |
2270 | } | |
92205c23 | 2271 | __raw_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2272 | local_irq_enable(); |
36dfe925 | 2273 | |
9e01c1b7 | 2274 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2275 | |
2276 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2277 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2278 | |
2279 | return count; | |
36dfe925 IM |
2280 | |
2281 | err_unlock: | |
215368e8 | 2282 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2283 | |
2284 | return err; | |
c7078de1 IM |
2285 | } |
2286 | ||
5e2336a0 | 2287 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2288 | .open = tracing_open_generic, |
2289 | .read = tracing_cpumask_read, | |
2290 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2291 | }; |
2292 | ||
2293 | static ssize_t | |
ee6bce52 | 2294 | tracing_trace_options_read(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
2295 | size_t cnt, loff_t *ppos) |
2296 | { | |
d8e83d26 SR |
2297 | struct tracer_opt *trace_opts; |
2298 | u32 tracer_flags; | |
2299 | int len = 0; | |
bc0c38d1 SR |
2300 | char *buf; |
2301 | int r = 0; | |
d8e83d26 | 2302 | int i; |
adf9f195 | 2303 | |
bc0c38d1 | 2304 | |
c3706f00 | 2305 | /* calculate max size */ |
bc0c38d1 SR |
2306 | for (i = 0; trace_options[i]; i++) { |
2307 | len += strlen(trace_options[i]); | |
5c6a3ae1 | 2308 | len += 3; /* "no" and newline */ |
bc0c38d1 SR |
2309 | } |
2310 | ||
d8e83d26 SR |
2311 | mutex_lock(&trace_types_lock); |
2312 | tracer_flags = current_trace->flags->val; | |
2313 | trace_opts = current_trace->flags->opts; | |
2314 | ||
adf9f195 FW |
2315 | /* |
2316 | * Increase the size with names of options specific | |
2317 | * of the current tracer. | |
2318 | */ | |
2319 | for (i = 0; trace_opts[i].name; i++) { | |
2320 | len += strlen(trace_opts[i].name); | |
5c6a3ae1 | 2321 | len += 3; /* "no" and newline */ |
adf9f195 FW |
2322 | } |
2323 | ||
ff4e9da2 XG |
2324 | /* +1 for \0 */ |
2325 | buf = kmalloc(len + 1, GFP_KERNEL); | |
d8e83d26 SR |
2326 | if (!buf) { |
2327 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 2328 | return -ENOMEM; |
d8e83d26 | 2329 | } |
bc0c38d1 SR |
2330 | |
2331 | for (i = 0; trace_options[i]; i++) { | |
2332 | if (trace_flags & (1 << i)) | |
5c6a3ae1 | 2333 | r += sprintf(buf + r, "%s\n", trace_options[i]); |
bc0c38d1 | 2334 | else |
5c6a3ae1 | 2335 | r += sprintf(buf + r, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2336 | } |
2337 | ||
adf9f195 FW |
2338 | for (i = 0; trace_opts[i].name; i++) { |
2339 | if (tracer_flags & trace_opts[i].bit) | |
5c6a3ae1 | 2340 | r += sprintf(buf + r, "%s\n", |
adf9f195 FW |
2341 | trace_opts[i].name); |
2342 | else | |
5c6a3ae1 | 2343 | r += sprintf(buf + r, "no%s\n", |
adf9f195 FW |
2344 | trace_opts[i].name); |
2345 | } | |
d8e83d26 | 2346 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2347 | |
ff4e9da2 | 2348 | WARN_ON(r >= len + 1); |
bc0c38d1 | 2349 | |
36dfe925 | 2350 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2351 | |
2352 | kfree(buf); | |
bc0c38d1 SR |
2353 | return r; |
2354 | } | |
2355 | ||
adf9f195 FW |
2356 | /* Try to assign a tracer specific option */ |
2357 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2358 | { | |
7770841e | 2359 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 FW |
2360 | struct tracer_opt *opts = NULL; |
2361 | int ret = 0, i = 0; | |
2362 | int len; | |
2363 | ||
7770841e Z |
2364 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2365 | opts = &tracer_flags->opts[i]; | |
adf9f195 FW |
2366 | len = strlen(opts->name); |
2367 | ||
2368 | if (strncmp(cmp, opts->name, len) == 0) { | |
7770841e | 2369 | ret = trace->set_flag(tracer_flags->val, |
adf9f195 FW |
2370 | opts->bit, !neg); |
2371 | break; | |
2372 | } | |
2373 | } | |
2374 | /* Not found */ | |
7770841e | 2375 | if (!tracer_flags->opts[i].name) |
adf9f195 FW |
2376 | return -EINVAL; |
2377 | ||
2378 | /* Refused to handle */ | |
2379 | if (ret) | |
2380 | return ret; | |
2381 | ||
2382 | if (neg) | |
7770841e | 2383 | tracer_flags->val &= ~opts->bit; |
adf9f195 | 2384 | else |
7770841e | 2385 | tracer_flags->val |= opts->bit; |
adf9f195 FW |
2386 | |
2387 | return 0; | |
2388 | } | |
2389 | ||
af4617bd SR |
2390 | static void set_tracer_flags(unsigned int mask, int enabled) |
2391 | { | |
2392 | /* do nothing if flag is already set */ | |
2393 | if (!!(trace_flags & mask) == !!enabled) | |
2394 | return; | |
2395 | ||
2396 | if (enabled) | |
2397 | trace_flags |= mask; | |
2398 | else | |
2399 | trace_flags &= ~mask; | |
af4617bd SR |
2400 | } |
2401 | ||
bc0c38d1 | 2402 | static ssize_t |
ee6bce52 | 2403 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2404 | size_t cnt, loff_t *ppos) |
2405 | { | |
2406 | char buf[64]; | |
2407 | char *cmp = buf; | |
2408 | int neg = 0; | |
adf9f195 | 2409 | int ret; |
bc0c38d1 SR |
2410 | int i; |
2411 | ||
cffae437 SR |
2412 | if (cnt >= sizeof(buf)) |
2413 | return -EINVAL; | |
bc0c38d1 SR |
2414 | |
2415 | if (copy_from_user(&buf, ubuf, cnt)) | |
2416 | return -EFAULT; | |
2417 | ||
2418 | buf[cnt] = 0; | |
2419 | ||
2420 | if (strncmp(buf, "no", 2) == 0) { | |
2421 | neg = 1; | |
2422 | cmp += 2; | |
2423 | } | |
2424 | ||
2425 | for (i = 0; trace_options[i]; i++) { | |
2426 | int len = strlen(trace_options[i]); | |
2427 | ||
2428 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
af4617bd | 2429 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2430 | break; |
2431 | } | |
2432 | } | |
adf9f195 FW |
2433 | |
2434 | /* If no option could be set, test the specific tracer options */ | |
2435 | if (!trace_options[i]) { | |
d8e83d26 | 2436 | mutex_lock(&trace_types_lock); |
adf9f195 | 2437 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2438 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2439 | if (ret) |
2440 | return ret; | |
2441 | } | |
bc0c38d1 SR |
2442 | |
2443 | filp->f_pos += cnt; | |
2444 | ||
2445 | return cnt; | |
2446 | } | |
2447 | ||
5e2336a0 | 2448 | static const struct file_operations tracing_iter_fops = { |
c7078de1 | 2449 | .open = tracing_open_generic, |
ee6bce52 SR |
2450 | .read = tracing_trace_options_read, |
2451 | .write = tracing_trace_options_write, | |
bc0c38d1 SR |
2452 | }; |
2453 | ||
7bd2f24c IM |
2454 | static const char readme_msg[] = |
2455 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2456 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2457 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
bc2b6871 | 2458 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
156f5a78 | 2459 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2460 | "nop\n" |
156f5a78 GL |
2461 | "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" |
2462 | "# cat /sys/kernel/debug/tracing/current_tracer\n" | |
7bd2f24c | 2463 | "sched_switch\n" |
156f5a78 | 2464 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2465 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 GL |
2466 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
2467 | "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
2468 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" | |
2469 | "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
7bd2f24c IM |
2470 | ; |
2471 | ||
2472 | static ssize_t | |
2473 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2474 | size_t cnt, loff_t *ppos) | |
2475 | { | |
2476 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2477 | readme_msg, strlen(readme_msg)); | |
2478 | } | |
2479 | ||
5e2336a0 | 2480 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2481 | .open = tracing_open_generic, |
2482 | .read = tracing_readme_read, | |
7bd2f24c IM |
2483 | }; |
2484 | ||
69abe6a5 AP |
2485 | static ssize_t |
2486 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2487 | size_t cnt, loff_t *ppos) | |
2488 | { | |
2489 | char *buf_comm; | |
2490 | char *file_buf; | |
2491 | char *buf; | |
2492 | int len = 0; | |
2493 | int pid; | |
2494 | int i; | |
2495 | ||
2496 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2497 | if (!file_buf) | |
2498 | return -ENOMEM; | |
2499 | ||
2500 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2501 | if (!buf_comm) { | |
2502 | kfree(file_buf); | |
2503 | return -ENOMEM; | |
2504 | } | |
2505 | ||
2506 | buf = file_buf; | |
2507 | ||
2508 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2509 | int r; | |
2510 | ||
2511 | pid = map_cmdline_to_pid[i]; | |
2512 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2513 | continue; | |
2514 | ||
2515 | trace_find_cmdline(pid, buf_comm); | |
2516 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2517 | buf += r; | |
2518 | len += r; | |
2519 | } | |
2520 | ||
2521 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2522 | file_buf, len); | |
2523 | ||
2524 | kfree(file_buf); | |
2525 | kfree(buf_comm); | |
2526 | ||
2527 | return len; | |
2528 | } | |
2529 | ||
2530 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2531 | .open = tracing_open_generic, | |
2532 | .read = tracing_saved_cmdlines_read, | |
2533 | }; | |
2534 | ||
bc0c38d1 SR |
2535 | static ssize_t |
2536 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2537 | size_t cnt, loff_t *ppos) | |
2538 | { | |
bc0c38d1 SR |
2539 | char buf[64]; |
2540 | int r; | |
2541 | ||
9036990d | 2542 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2543 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2544 | } |
2545 | ||
2546 | static ssize_t | |
2547 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2548 | size_t cnt, loff_t *ppos) | |
2549 | { | |
2550 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2551 | char buf[64]; |
5e39841c | 2552 | unsigned long val; |
c6caeeb1 | 2553 | int ret; |
bc0c38d1 | 2554 | |
cffae437 SR |
2555 | if (cnt >= sizeof(buf)) |
2556 | return -EINVAL; | |
bc0c38d1 SR |
2557 | |
2558 | if (copy_from_user(&buf, ubuf, cnt)) | |
2559 | return -EFAULT; | |
2560 | ||
2561 | buf[cnt] = 0; | |
2562 | ||
c6caeeb1 SR |
2563 | ret = strict_strtoul(buf, 10, &val); |
2564 | if (ret < 0) | |
2565 | return ret; | |
bc0c38d1 SR |
2566 | |
2567 | val = !!val; | |
2568 | ||
2569 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2570 | if (tracer_enabled ^ val) { |
2571 | if (val) { | |
bc0c38d1 | 2572 | tracer_enabled = 1; |
9036990d SR |
2573 | if (current_trace->start) |
2574 | current_trace->start(tr); | |
2575 | tracing_start(); | |
2576 | } else { | |
bc0c38d1 | 2577 | tracer_enabled = 0; |
9036990d SR |
2578 | tracing_stop(); |
2579 | if (current_trace->stop) | |
2580 | current_trace->stop(tr); | |
2581 | } | |
bc0c38d1 SR |
2582 | } |
2583 | mutex_unlock(&trace_types_lock); | |
2584 | ||
2585 | filp->f_pos += cnt; | |
2586 | ||
2587 | return cnt; | |
2588 | } | |
2589 | ||
2590 | static ssize_t | |
2591 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2592 | size_t cnt, loff_t *ppos) | |
2593 | { | |
ee6c2c1b | 2594 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
2595 | int r; |
2596 | ||
2597 | mutex_lock(&trace_types_lock); | |
2598 | if (current_trace) | |
2599 | r = sprintf(buf, "%s\n", current_trace->name); | |
2600 | else | |
2601 | r = sprintf(buf, "\n"); | |
2602 | mutex_unlock(&trace_types_lock); | |
2603 | ||
4bf39a94 | 2604 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2605 | } |
2606 | ||
b6f11df2 ACM |
2607 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2608 | { | |
2609 | tracing_reset_online_cpus(tr); | |
2610 | return t->init(tr); | |
2611 | } | |
2612 | ||
73c5162a SR |
2613 | static int tracing_resize_ring_buffer(unsigned long size) |
2614 | { | |
2615 | int ret; | |
2616 | ||
2617 | /* | |
2618 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2619 | * we use the size that was given, and we can forget about |
2620 | * expanding it later. | |
73c5162a SR |
2621 | */ |
2622 | ring_buffer_expanded = 1; | |
2623 | ||
2624 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2625 | if (ret < 0) | |
2626 | return ret; | |
2627 | ||
2628 | ret = ring_buffer_resize(max_tr.buffer, size); | |
2629 | if (ret < 0) { | |
2630 | int r; | |
2631 | ||
2632 | r = ring_buffer_resize(global_trace.buffer, | |
2633 | global_trace.entries); | |
2634 | if (r < 0) { | |
a123c52b SR |
2635 | /* |
2636 | * AARGH! We are left with different | |
2637 | * size max buffer!!!! | |
2638 | * The max buffer is our "snapshot" buffer. | |
2639 | * When a tracer needs a snapshot (one of the | |
2640 | * latency tracers), it swaps the max buffer | |
2641 | * with the saved snap shot. We succeeded to | |
2642 | * update the size of the main buffer, but failed to | |
2643 | * update the size of the max buffer. But when we tried | |
2644 | * to reset the main buffer to the original size, we | |
2645 | * failed there too. This is very unlikely to | |
2646 | * happen, but if it does, warn and kill all | |
2647 | * tracing. | |
2648 | */ | |
73c5162a SR |
2649 | WARN_ON(1); |
2650 | tracing_disabled = 1; | |
2651 | } | |
2652 | return ret; | |
2653 | } | |
2654 | ||
2655 | global_trace.entries = size; | |
2656 | ||
2657 | return ret; | |
2658 | } | |
2659 | ||
1852fcce SR |
2660 | /** |
2661 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2662 | * | |
2663 | * To save on memory when the tracing is never used on a system with it | |
2664 | * configured in. The ring buffers are set to a minimum size. But once | |
2665 | * a user starts to use the tracing facility, then they need to grow | |
2666 | * to their default size. | |
2667 | * | |
2668 | * This function is to be called when a tracer is about to be used. | |
2669 | */ | |
2670 | int tracing_update_buffers(void) | |
2671 | { | |
2672 | int ret = 0; | |
2673 | ||
1027fcb2 | 2674 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2675 | if (!ring_buffer_expanded) |
2676 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2677 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2678 | |
2679 | return ret; | |
2680 | } | |
2681 | ||
577b785f SR |
2682 | struct trace_option_dentry; |
2683 | ||
2684 | static struct trace_option_dentry * | |
2685 | create_trace_option_files(struct tracer *tracer); | |
2686 | ||
2687 | static void | |
2688 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2689 | ||
b2821ae6 | 2690 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2691 | { |
577b785f | 2692 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2693 | struct trace_array *tr = &global_trace; |
2694 | struct tracer *t; | |
d9e54076 | 2695 | int ret = 0; |
bc0c38d1 | 2696 | |
1027fcb2 SR |
2697 | mutex_lock(&trace_types_lock); |
2698 | ||
73c5162a SR |
2699 | if (!ring_buffer_expanded) { |
2700 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2701 | if (ret < 0) | |
59f586db | 2702 | goto out; |
73c5162a SR |
2703 | ret = 0; |
2704 | } | |
2705 | ||
bc0c38d1 SR |
2706 | for (t = trace_types; t; t = t->next) { |
2707 | if (strcmp(t->name, buf) == 0) | |
2708 | break; | |
2709 | } | |
c2931e05 FW |
2710 | if (!t) { |
2711 | ret = -EINVAL; | |
2712 | goto out; | |
2713 | } | |
2714 | if (t == current_trace) | |
bc0c38d1 SR |
2715 | goto out; |
2716 | ||
9f029e83 | 2717 | trace_branch_disable(); |
bc0c38d1 SR |
2718 | if (current_trace && current_trace->reset) |
2719 | current_trace->reset(tr); | |
2720 | ||
577b785f SR |
2721 | destroy_trace_option_files(topts); |
2722 | ||
bc0c38d1 | 2723 | current_trace = t; |
577b785f SR |
2724 | |
2725 | topts = create_trace_option_files(current_trace); | |
2726 | ||
1c80025a | 2727 | if (t->init) { |
b6f11df2 | 2728 | ret = tracer_init(t, tr); |
1c80025a FW |
2729 | if (ret) |
2730 | goto out; | |
2731 | } | |
bc0c38d1 | 2732 | |
9f029e83 | 2733 | trace_branch_enable(tr); |
bc0c38d1 SR |
2734 | out: |
2735 | mutex_unlock(&trace_types_lock); | |
2736 | ||
d9e54076 PZ |
2737 | return ret; |
2738 | } | |
2739 | ||
2740 | static ssize_t | |
2741 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2742 | size_t cnt, loff_t *ppos) | |
2743 | { | |
ee6c2c1b | 2744 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
2745 | int i; |
2746 | size_t ret; | |
e6e7a65a FW |
2747 | int err; |
2748 | ||
2749 | ret = cnt; | |
d9e54076 | 2750 | |
ee6c2c1b LZ |
2751 | if (cnt > MAX_TRACER_SIZE) |
2752 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
2753 | |
2754 | if (copy_from_user(&buf, ubuf, cnt)) | |
2755 | return -EFAULT; | |
2756 | ||
2757 | buf[cnt] = 0; | |
2758 | ||
2759 | /* strip ending whitespace. */ | |
2760 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2761 | buf[i] = 0; | |
2762 | ||
e6e7a65a FW |
2763 | err = tracing_set_tracer(buf); |
2764 | if (err) | |
2765 | return err; | |
d9e54076 | 2766 | |
e6e7a65a | 2767 | filp->f_pos += ret; |
bc0c38d1 | 2768 | |
c2931e05 | 2769 | return ret; |
bc0c38d1 SR |
2770 | } |
2771 | ||
2772 | static ssize_t | |
2773 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2774 | size_t cnt, loff_t *ppos) | |
2775 | { | |
2776 | unsigned long *ptr = filp->private_data; | |
2777 | char buf[64]; | |
2778 | int r; | |
2779 | ||
cffae437 | 2780 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2781 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2782 | if (r > sizeof(buf)) |
2783 | r = sizeof(buf); | |
4bf39a94 | 2784 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2785 | } |
2786 | ||
2787 | static ssize_t | |
2788 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2789 | size_t cnt, loff_t *ppos) | |
2790 | { | |
5e39841c | 2791 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2792 | char buf[64]; |
5e39841c | 2793 | unsigned long val; |
c6caeeb1 | 2794 | int ret; |
bc0c38d1 | 2795 | |
cffae437 SR |
2796 | if (cnt >= sizeof(buf)) |
2797 | return -EINVAL; | |
bc0c38d1 SR |
2798 | |
2799 | if (copy_from_user(&buf, ubuf, cnt)) | |
2800 | return -EFAULT; | |
2801 | ||
2802 | buf[cnt] = 0; | |
2803 | ||
c6caeeb1 SR |
2804 | ret = strict_strtoul(buf, 10, &val); |
2805 | if (ret < 0) | |
2806 | return ret; | |
bc0c38d1 SR |
2807 | |
2808 | *ptr = val * 1000; | |
2809 | ||
2810 | return cnt; | |
2811 | } | |
2812 | ||
b3806b43 SR |
2813 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2814 | { | |
b04cc6b1 | 2815 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2816 | struct trace_iterator *iter; |
b04cc6b1 | 2817 | int ret = 0; |
b3806b43 SR |
2818 | |
2819 | if (tracing_disabled) | |
2820 | return -ENODEV; | |
2821 | ||
b04cc6b1 FW |
2822 | mutex_lock(&trace_types_lock); |
2823 | ||
2824 | /* We only allow one reader per cpu */ | |
2825 | if (cpu_file == TRACE_PIPE_ALL_CPU) { | |
2826 | if (!cpumask_empty(tracing_reader_cpumask)) { | |
2827 | ret = -EBUSY; | |
2828 | goto out; | |
2829 | } | |
2830 | cpumask_setall(tracing_reader_cpumask); | |
2831 | } else { | |
2832 | if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask)) | |
2833 | cpumask_set_cpu(cpu_file, tracing_reader_cpumask); | |
2834 | else { | |
2835 | ret = -EBUSY; | |
2836 | goto out; | |
2837 | } | |
b3806b43 SR |
2838 | } |
2839 | ||
2840 | /* create a buffer to store the information to pass to userspace */ | |
2841 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2842 | if (!iter) { |
2843 | ret = -ENOMEM; | |
2844 | goto out; | |
2845 | } | |
b3806b43 | 2846 | |
d7350c3f FW |
2847 | /* |
2848 | * We make a copy of the current tracer to avoid concurrent | |
2849 | * changes on it while we are reading. | |
2850 | */ | |
2851 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
2852 | if (!iter->trace) { | |
2853 | ret = -ENOMEM; | |
2854 | goto fail; | |
2855 | } | |
2856 | if (current_trace) | |
2857 | *iter->trace = *current_trace; | |
2858 | ||
4462344e | 2859 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 2860 | ret = -ENOMEM; |
d7350c3f | 2861 | goto fail; |
4462344e RR |
2862 | } |
2863 | ||
a309720c | 2864 | /* trace pipe does not show start of buffer */ |
4462344e | 2865 | cpumask_setall(iter->started); |
a309720c | 2866 | |
112f38a7 SR |
2867 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
2868 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2869 | ||
b04cc6b1 | 2870 | iter->cpu_file = cpu_file; |
b3806b43 | 2871 | iter->tr = &global_trace; |
d7350c3f | 2872 | mutex_init(&iter->mutex); |
b3806b43 SR |
2873 | filp->private_data = iter; |
2874 | ||
107bad8b SR |
2875 | if (iter->trace->pipe_open) |
2876 | iter->trace->pipe_open(iter); | |
107bad8b | 2877 | |
b04cc6b1 FW |
2878 | out: |
2879 | mutex_unlock(&trace_types_lock); | |
2880 | return ret; | |
d7350c3f FW |
2881 | |
2882 | fail: | |
2883 | kfree(iter->trace); | |
2884 | kfree(iter); | |
2885 | mutex_unlock(&trace_types_lock); | |
2886 | return ret; | |
b3806b43 SR |
2887 | } |
2888 | ||
2889 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2890 | { | |
2891 | struct trace_iterator *iter = file->private_data; | |
2892 | ||
b04cc6b1 FW |
2893 | mutex_lock(&trace_types_lock); |
2894 | ||
2895 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) | |
2896 | cpumask_clear(tracing_reader_cpumask); | |
2897 | else | |
2898 | cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); | |
2899 | ||
2900 | mutex_unlock(&trace_types_lock); | |
2901 | ||
4462344e | 2902 | free_cpumask_var(iter->started); |
d7350c3f FW |
2903 | mutex_destroy(&iter->mutex); |
2904 | kfree(iter->trace); | |
b3806b43 | 2905 | kfree(iter); |
b3806b43 SR |
2906 | |
2907 | return 0; | |
2908 | } | |
2909 | ||
2a2cc8f7 SSP |
2910 | static unsigned int |
2911 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2912 | { | |
2913 | struct trace_iterator *iter = filp->private_data; | |
2914 | ||
2915 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2916 | /* | |
2917 | * Always select as readable when in blocking mode | |
2918 | */ | |
2919 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2920 | } else { |
2a2cc8f7 SSP |
2921 | if (!trace_empty(iter)) |
2922 | return POLLIN | POLLRDNORM; | |
2923 | poll_wait(filp, &trace_wait, poll_table); | |
2924 | if (!trace_empty(iter)) | |
2925 | return POLLIN | POLLRDNORM; | |
2926 | ||
2927 | return 0; | |
2928 | } | |
2929 | } | |
2930 | ||
6eaaa5d5 FW |
2931 | |
2932 | void default_wait_pipe(struct trace_iterator *iter) | |
2933 | { | |
2934 | DEFINE_WAIT(wait); | |
2935 | ||
2936 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
2937 | ||
2938 | if (trace_empty(iter)) | |
2939 | schedule(); | |
2940 | ||
2941 | finish_wait(&trace_wait, &wait); | |
2942 | } | |
2943 | ||
2944 | /* | |
2945 | * This is a make-shift waitqueue. | |
2946 | * A tracer might use this callback on some rare cases: | |
2947 | * | |
2948 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
2949 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
2950 | * 2) the function tracers, trace all functions, we don't want | |
2951 | * the overhead of calling wake_up and friends | |
2952 | * (and tracing them too) | |
2953 | * | |
2954 | * Anyway, this is really very primitive wakeup. | |
2955 | */ | |
2956 | void poll_wait_pipe(struct trace_iterator *iter) | |
2957 | { | |
2958 | set_current_state(TASK_INTERRUPTIBLE); | |
2959 | /* sleep for 100 msecs, and try again. */ | |
2960 | schedule_timeout(HZ / 10); | |
2961 | } | |
2962 | ||
ff98781b EGM |
2963 | /* Must be called with trace_types_lock mutex held. */ |
2964 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
2965 | { |
2966 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 2967 | |
b3806b43 | 2968 | while (trace_empty(iter)) { |
2dc8f095 | 2969 | |
107bad8b | 2970 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 2971 | return -EAGAIN; |
107bad8b | 2972 | } |
2dc8f095 | 2973 | |
d7350c3f | 2974 | mutex_unlock(&iter->mutex); |
107bad8b | 2975 | |
6eaaa5d5 | 2976 | iter->trace->wait_pipe(iter); |
b3806b43 | 2977 | |
d7350c3f | 2978 | mutex_lock(&iter->mutex); |
107bad8b | 2979 | |
6eaaa5d5 | 2980 | if (signal_pending(current)) |
ff98781b | 2981 | return -EINTR; |
b3806b43 SR |
2982 | |
2983 | /* | |
2984 | * We block until we read something and tracing is disabled. | |
2985 | * We still block if tracing is disabled, but we have never | |
2986 | * read anything. This allows a user to cat this file, and | |
2987 | * then enable tracing. But after we have read something, | |
2988 | * we give an EOF when tracing is again disabled. | |
2989 | * | |
2990 | * iter->pos will be 0 if we haven't read anything. | |
2991 | */ | |
2992 | if (!tracer_enabled && iter->pos) | |
2993 | break; | |
b3806b43 SR |
2994 | } |
2995 | ||
ff98781b EGM |
2996 | return 1; |
2997 | } | |
2998 | ||
2999 | /* | |
3000 | * Consumer reader. | |
3001 | */ | |
3002 | static ssize_t | |
3003 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
3004 | size_t cnt, loff_t *ppos) | |
3005 | { | |
3006 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 3007 | static struct tracer *old_tracer; |
ff98781b EGM |
3008 | ssize_t sret; |
3009 | ||
3010 | /* return any leftover data */ | |
3011 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
3012 | if (sret != -EBUSY) | |
3013 | return sret; | |
3014 | ||
f9520750 | 3015 | trace_seq_init(&iter->seq); |
ff98781b | 3016 | |
d7350c3f | 3017 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 3018 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3019 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3020 | old_tracer = current_trace; | |
3021 | *iter->trace = *current_trace; | |
3022 | } | |
3023 | mutex_unlock(&trace_types_lock); | |
3024 | ||
3025 | /* | |
3026 | * Avoid more than one consumer on a single file descriptor | |
3027 | * This is just a matter of traces coherency, the ring buffer itself | |
3028 | * is protected. | |
3029 | */ | |
3030 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
3031 | if (iter->trace->read) { |
3032 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
3033 | if (sret) | |
3034 | goto out; | |
3035 | } | |
3036 | ||
3037 | waitagain: | |
3038 | sret = tracing_wait_pipe(filp); | |
3039 | if (sret <= 0) | |
3040 | goto out; | |
3041 | ||
b3806b43 | 3042 | /* stop when tracing is finished */ |
ff98781b EGM |
3043 | if (trace_empty(iter)) { |
3044 | sret = 0; | |
107bad8b | 3045 | goto out; |
ff98781b | 3046 | } |
b3806b43 SR |
3047 | |
3048 | if (cnt >= PAGE_SIZE) | |
3049 | cnt = PAGE_SIZE - 1; | |
3050 | ||
53d0aa77 | 3051 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
3052 | memset(&iter->seq, 0, |
3053 | sizeof(struct trace_iterator) - | |
3054 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 3055 | iter->pos = -1; |
b3806b43 | 3056 | |
4f535968 | 3057 | trace_event_read_lock(); |
088b1e42 | 3058 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 3059 | enum print_line_t ret; |
088b1e42 SR |
3060 | int len = iter->seq.len; |
3061 | ||
f9896bf3 | 3062 | ret = print_trace_line(iter); |
2c4f035f | 3063 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
3064 | /* don't print partial lines */ |
3065 | iter->seq.len = len; | |
b3806b43 | 3066 | break; |
088b1e42 | 3067 | } |
b91facc3 FW |
3068 | if (ret != TRACE_TYPE_NO_CONSUME) |
3069 | trace_consume(iter); | |
b3806b43 SR |
3070 | |
3071 | if (iter->seq.len >= cnt) | |
3072 | break; | |
b3806b43 | 3073 | } |
4f535968 | 3074 | trace_event_read_unlock(); |
b3806b43 | 3075 | |
b3806b43 | 3076 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3077 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3078 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3079 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3080 | |
3081 | /* | |
3082 | * If there was nothing to send to user, inspite of consuming trace | |
3083 | * entries, go back to wait for more entries. | |
3084 | */ | |
6c6c2796 | 3085 | if (sret == -EBUSY) |
9ff4b974 | 3086 | goto waitagain; |
b3806b43 | 3087 | |
107bad8b | 3088 | out: |
d7350c3f | 3089 | mutex_unlock(&iter->mutex); |
107bad8b | 3090 | |
6c6c2796 | 3091 | return sret; |
b3806b43 SR |
3092 | } |
3093 | ||
3c56819b EGM |
3094 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3095 | struct pipe_buffer *buf) | |
3096 | { | |
3097 | __free_page(buf->page); | |
3098 | } | |
3099 | ||
3100 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3101 | unsigned int idx) | |
3102 | { | |
3103 | __free_page(spd->pages[idx]); | |
3104 | } | |
3105 | ||
3106 | static struct pipe_buf_operations tracing_pipe_buf_ops = { | |
34cd4998 SR |
3107 | .can_merge = 0, |
3108 | .map = generic_pipe_buf_map, | |
3109 | .unmap = generic_pipe_buf_unmap, | |
3110 | .confirm = generic_pipe_buf_confirm, | |
3111 | .release = tracing_pipe_buf_release, | |
3112 | .steal = generic_pipe_buf_steal, | |
3113 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3114 | }; |
3115 | ||
34cd4998 | 3116 | static size_t |
fa7c7f6e | 3117 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3118 | { |
3119 | size_t count; | |
3120 | int ret; | |
3121 | ||
3122 | /* Seq buffer is page-sized, exactly what we need. */ | |
3123 | for (;;) { | |
3124 | count = iter->seq.len; | |
3125 | ret = print_trace_line(iter); | |
3126 | count = iter->seq.len - count; | |
3127 | if (rem < count) { | |
3128 | rem = 0; | |
3129 | iter->seq.len -= count; | |
3130 | break; | |
3131 | } | |
3132 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3133 | iter->seq.len -= count; | |
3134 | break; | |
3135 | } | |
3136 | ||
74e7ff8c LJ |
3137 | if (ret != TRACE_TYPE_NO_CONSUME) |
3138 | trace_consume(iter); | |
34cd4998 SR |
3139 | rem -= count; |
3140 | if (!find_next_entry_inc(iter)) { | |
3141 | rem = 0; | |
3142 | iter->ent = NULL; | |
3143 | break; | |
3144 | } | |
3145 | } | |
3146 | ||
3147 | return rem; | |
3148 | } | |
3149 | ||
3c56819b EGM |
3150 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3151 | loff_t *ppos, | |
3152 | struct pipe_inode_info *pipe, | |
3153 | size_t len, | |
3154 | unsigned int flags) | |
3155 | { | |
3156 | struct page *pages[PIPE_BUFFERS]; | |
3157 | struct partial_page partial[PIPE_BUFFERS]; | |
3158 | struct trace_iterator *iter = filp->private_data; | |
3159 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
3160 | .pages = pages, |
3161 | .partial = partial, | |
3162 | .nr_pages = 0, /* This gets updated below. */ | |
3163 | .flags = flags, | |
3164 | .ops = &tracing_pipe_buf_ops, | |
3165 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3166 | }; |
d7350c3f | 3167 | static struct tracer *old_tracer; |
3c56819b | 3168 | ssize_t ret; |
34cd4998 | 3169 | size_t rem; |
3c56819b EGM |
3170 | unsigned int i; |
3171 | ||
d7350c3f | 3172 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3173 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3174 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3175 | old_tracer = current_trace; | |
3176 | *iter->trace = *current_trace; | |
3177 | } | |
3178 | mutex_unlock(&trace_types_lock); | |
3179 | ||
3180 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3181 | |
3182 | if (iter->trace->splice_read) { | |
3183 | ret = iter->trace->splice_read(iter, filp, | |
3184 | ppos, pipe, len, flags); | |
3185 | if (ret) | |
34cd4998 | 3186 | goto out_err; |
3c56819b EGM |
3187 | } |
3188 | ||
3189 | ret = tracing_wait_pipe(filp); | |
3190 | if (ret <= 0) | |
34cd4998 | 3191 | goto out_err; |
3c56819b EGM |
3192 | |
3193 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
3194 | ret = -EFAULT; | |
34cd4998 | 3195 | goto out_err; |
3c56819b EGM |
3196 | } |
3197 | ||
4f535968 LJ |
3198 | trace_event_read_lock(); |
3199 | ||
3c56819b EGM |
3200 | /* Fill as many pages as possible. */ |
3201 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
3202 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
3203 | if (!pages[i]) |
3204 | break; | |
3c56819b | 3205 | |
fa7c7f6e | 3206 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3207 | |
3208 | /* Copy the data into the page, so we can start over. */ | |
3209 | ret = trace_seq_to_buffer(&iter->seq, | |
3210 | page_address(pages[i]), | |
3211 | iter->seq.len); | |
3212 | if (ret < 0) { | |
3213 | __free_page(pages[i]); | |
3214 | break; | |
3215 | } | |
3216 | partial[i].offset = 0; | |
3217 | partial[i].len = iter->seq.len; | |
3218 | ||
f9520750 | 3219 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3220 | } |
3221 | ||
4f535968 | 3222 | trace_event_read_unlock(); |
d7350c3f | 3223 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3224 | |
3225 | spd.nr_pages = i; | |
3226 | ||
3227 | return splice_to_pipe(pipe, &spd); | |
3228 | ||
34cd4998 | 3229 | out_err: |
d7350c3f | 3230 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3231 | |
3232 | return ret; | |
3233 | } | |
3234 | ||
a98a3c3f SR |
3235 | static ssize_t |
3236 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3237 | size_t cnt, loff_t *ppos) | |
3238 | { | |
3239 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3240 | char buf[96]; |
a98a3c3f SR |
3241 | int r; |
3242 | ||
db526ca3 SR |
3243 | mutex_lock(&trace_types_lock); |
3244 | if (!ring_buffer_expanded) | |
3245 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3246 | tr->entries >> 10, | |
3247 | trace_buf_size >> 10); | |
3248 | else | |
3249 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3250 | mutex_unlock(&trace_types_lock); | |
3251 | ||
a98a3c3f SR |
3252 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3253 | } | |
3254 | ||
3255 | static ssize_t | |
3256 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3257 | size_t cnt, loff_t *ppos) | |
3258 | { | |
3259 | unsigned long val; | |
3260 | char buf[64]; | |
bf5e6519 | 3261 | int ret, cpu; |
a98a3c3f | 3262 | |
cffae437 SR |
3263 | if (cnt >= sizeof(buf)) |
3264 | return -EINVAL; | |
a98a3c3f SR |
3265 | |
3266 | if (copy_from_user(&buf, ubuf, cnt)) | |
3267 | return -EFAULT; | |
3268 | ||
3269 | buf[cnt] = 0; | |
3270 | ||
c6caeeb1 SR |
3271 | ret = strict_strtoul(buf, 10, &val); |
3272 | if (ret < 0) | |
3273 | return ret; | |
a98a3c3f SR |
3274 | |
3275 | /* must have at least 1 entry */ | |
3276 | if (!val) | |
3277 | return -EINVAL; | |
3278 | ||
3279 | mutex_lock(&trace_types_lock); | |
3280 | ||
c76f0694 | 3281 | tracing_stop(); |
a98a3c3f | 3282 | |
bf5e6519 SR |
3283 | /* disable all cpu buffers */ |
3284 | for_each_tracing_cpu(cpu) { | |
3285 | if (global_trace.data[cpu]) | |
3286 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3287 | if (max_tr.data[cpu]) | |
3288 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3289 | } | |
3290 | ||
1696b2b0 SR |
3291 | /* value is in KB */ |
3292 | val <<= 10; | |
3293 | ||
3928a8a2 | 3294 | if (val != global_trace.entries) { |
73c5162a | 3295 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3296 | if (ret < 0) { |
3297 | cnt = ret; | |
3eefae99 SR |
3298 | goto out; |
3299 | } | |
a98a3c3f SR |
3300 | } |
3301 | ||
3302 | filp->f_pos += cnt; | |
3303 | ||
19384c03 SR |
3304 | /* If check pages failed, return ENOMEM */ |
3305 | if (tracing_disabled) | |
3306 | cnt = -ENOMEM; | |
a98a3c3f | 3307 | out: |
bf5e6519 SR |
3308 | for_each_tracing_cpu(cpu) { |
3309 | if (global_trace.data[cpu]) | |
3310 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3311 | if (max_tr.data[cpu]) | |
3312 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3313 | } | |
3314 | ||
c76f0694 | 3315 | tracing_start(); |
a98a3c3f SR |
3316 | max_tr.entries = global_trace.entries; |
3317 | mutex_unlock(&trace_types_lock); | |
3318 | ||
3319 | return cnt; | |
3320 | } | |
3321 | ||
5bf9a1ee PP |
3322 | static int mark_printk(const char *fmt, ...) |
3323 | { | |
3324 | int ret; | |
3325 | va_list args; | |
3326 | va_start(args, fmt); | |
40ce74f1 | 3327 | ret = trace_vprintk(0, fmt, args); |
5bf9a1ee PP |
3328 | va_end(args); |
3329 | return ret; | |
3330 | } | |
3331 | ||
3332 | static ssize_t | |
3333 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3334 | size_t cnt, loff_t *fpos) | |
3335 | { | |
3336 | char *buf; | |
3337 | char *end; | |
5bf9a1ee | 3338 | |
c76f0694 | 3339 | if (tracing_disabled) |
5bf9a1ee PP |
3340 | return -EINVAL; |
3341 | ||
3342 | if (cnt > TRACE_BUF_SIZE) | |
3343 | cnt = TRACE_BUF_SIZE; | |
3344 | ||
3345 | buf = kmalloc(cnt + 1, GFP_KERNEL); | |
3346 | if (buf == NULL) | |
3347 | return -ENOMEM; | |
3348 | ||
3349 | if (copy_from_user(buf, ubuf, cnt)) { | |
3350 | kfree(buf); | |
3351 | return -EFAULT; | |
3352 | } | |
3353 | ||
3354 | /* Cut from the first nil or newline. */ | |
3355 | buf[cnt] = '\0'; | |
3356 | end = strchr(buf, '\n'); | |
3357 | if (end) | |
3358 | *end = '\0'; | |
3359 | ||
3360 | cnt = mark_printk("%s\n", buf); | |
3361 | kfree(buf); | |
3362 | *fpos += cnt; | |
3363 | ||
3364 | return cnt; | |
3365 | } | |
3366 | ||
5079f326 Z |
3367 | static ssize_t tracing_clock_read(struct file *filp, char __user *ubuf, |
3368 | size_t cnt, loff_t *ppos) | |
3369 | { | |
3370 | char buf[64]; | |
3371 | int bufiter = 0; | |
3372 | int i; | |
3373 | ||
3374 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
3375 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, | |
3376 | "%s%s%s%s", i ? " " : "", | |
3377 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3378 | i == trace_clock_id ? "]" : ""); | |
3379 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, "\n"); | |
3380 | ||
3381 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, bufiter); | |
3382 | } | |
3383 | ||
3384 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
3385 | size_t cnt, loff_t *fpos) | |
3386 | { | |
3387 | char buf[64]; | |
3388 | const char *clockstr; | |
3389 | int i; | |
3390 | ||
3391 | if (cnt >= sizeof(buf)) | |
3392 | return -EINVAL; | |
3393 | ||
3394 | if (copy_from_user(&buf, ubuf, cnt)) | |
3395 | return -EFAULT; | |
3396 | ||
3397 | buf[cnt] = 0; | |
3398 | ||
3399 | clockstr = strstrip(buf); | |
3400 | ||
3401 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
3402 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
3403 | break; | |
3404 | } | |
3405 | if (i == ARRAY_SIZE(trace_clocks)) | |
3406 | return -EINVAL; | |
3407 | ||
3408 | trace_clock_id = i; | |
3409 | ||
3410 | mutex_lock(&trace_types_lock); | |
3411 | ||
3412 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
3413 | if (max_tr.buffer) | |
3414 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
3415 | ||
3416 | mutex_unlock(&trace_types_lock); | |
3417 | ||
3418 | *fpos += cnt; | |
3419 | ||
3420 | return cnt; | |
3421 | } | |
3422 | ||
5e2336a0 | 3423 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3424 | .open = tracing_open_generic, |
3425 | .read = tracing_max_lat_read, | |
3426 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
3427 | }; |
3428 | ||
5e2336a0 | 3429 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3430 | .open = tracing_open_generic, |
3431 | .read = tracing_ctrl_read, | |
3432 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
3433 | }; |
3434 | ||
5e2336a0 | 3435 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3436 | .open = tracing_open_generic, |
3437 | .read = tracing_set_trace_read, | |
3438 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
3439 | }; |
3440 | ||
5e2336a0 | 3441 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3442 | .open = tracing_open_pipe, |
2a2cc8f7 | 3443 | .poll = tracing_poll_pipe, |
4bf39a94 | 3444 | .read = tracing_read_pipe, |
3c56819b | 3445 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3446 | .release = tracing_release_pipe, |
b3806b43 SR |
3447 | }; |
3448 | ||
5e2336a0 | 3449 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3450 | .open = tracing_open_generic, |
3451 | .read = tracing_entries_read, | |
3452 | .write = tracing_entries_write, | |
3453 | }; | |
3454 | ||
5e2336a0 | 3455 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3456 | .open = tracing_open_generic, |
5bf9a1ee PP |
3457 | .write = tracing_mark_write, |
3458 | }; | |
3459 | ||
5079f326 Z |
3460 | static const struct file_operations trace_clock_fops = { |
3461 | .open = tracing_open_generic, | |
3462 | .read = tracing_clock_read, | |
3463 | .write = tracing_clock_write, | |
3464 | }; | |
3465 | ||
2cadf913 SR |
3466 | struct ftrace_buffer_info { |
3467 | struct trace_array *tr; | |
3468 | void *spare; | |
3469 | int cpu; | |
3470 | unsigned int read; | |
3471 | }; | |
3472 | ||
3473 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3474 | { | |
3475 | int cpu = (int)(long)inode->i_private; | |
3476 | struct ftrace_buffer_info *info; | |
3477 | ||
3478 | if (tracing_disabled) | |
3479 | return -ENODEV; | |
3480 | ||
3481 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3482 | if (!info) | |
3483 | return -ENOMEM; | |
3484 | ||
3485 | info->tr = &global_trace; | |
3486 | info->cpu = cpu; | |
ddd538f3 | 3487 | info->spare = NULL; |
2cadf913 SR |
3488 | /* Force reading ring buffer for first read */ |
3489 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3490 | |
3491 | filp->private_data = info; | |
3492 | ||
d1e7e02f | 3493 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3494 | } |
3495 | ||
3496 | static ssize_t | |
3497 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3498 | size_t count, loff_t *ppos) | |
3499 | { | |
3500 | struct ftrace_buffer_info *info = filp->private_data; | |
3501 | unsigned int pos; | |
3502 | ssize_t ret; | |
3503 | size_t size; | |
3504 | ||
2dc5d12b SR |
3505 | if (!count) |
3506 | return 0; | |
3507 | ||
ddd538f3 LJ |
3508 | if (!info->spare) |
3509 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3510 | if (!info->spare) | |
3511 | return -ENOMEM; | |
3512 | ||
2cadf913 SR |
3513 | /* Do we have previous read data to read? */ |
3514 | if (info->read < PAGE_SIZE) | |
3515 | goto read; | |
3516 | ||
3517 | info->read = 0; | |
3518 | ||
3519 | ret = ring_buffer_read_page(info->tr->buffer, | |
3520 | &info->spare, | |
3521 | count, | |
3522 | info->cpu, 0); | |
3523 | if (ret < 0) | |
3524 | return 0; | |
3525 | ||
3526 | pos = ring_buffer_page_len(info->spare); | |
3527 | ||
3528 | if (pos < PAGE_SIZE) | |
3529 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3530 | ||
3531 | read: | |
3532 | size = PAGE_SIZE - info->read; | |
3533 | if (size > count) | |
3534 | size = count; | |
3535 | ||
3536 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3537 | if (ret == size) |
2cadf913 | 3538 | return -EFAULT; |
2dc5d12b SR |
3539 | size -= ret; |
3540 | ||
2cadf913 SR |
3541 | *ppos += size; |
3542 | info->read += size; | |
3543 | ||
3544 | return size; | |
3545 | } | |
3546 | ||
3547 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3548 | { | |
3549 | struct ftrace_buffer_info *info = file->private_data; | |
3550 | ||
ddd538f3 LJ |
3551 | if (info->spare) |
3552 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3553 | kfree(info); |
3554 | ||
3555 | return 0; | |
3556 | } | |
3557 | ||
3558 | struct buffer_ref { | |
3559 | struct ring_buffer *buffer; | |
3560 | void *page; | |
3561 | int ref; | |
3562 | }; | |
3563 | ||
3564 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3565 | struct pipe_buffer *buf) | |
3566 | { | |
3567 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3568 | ||
3569 | if (--ref->ref) | |
3570 | return; | |
3571 | ||
3572 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3573 | kfree(ref); | |
3574 | buf->private = 0; | |
3575 | } | |
3576 | ||
3577 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3578 | struct pipe_buffer *buf) | |
3579 | { | |
3580 | return 1; | |
3581 | } | |
3582 | ||
3583 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3584 | struct pipe_buffer *buf) | |
3585 | { | |
3586 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3587 | ||
3588 | ref->ref++; | |
3589 | } | |
3590 | ||
3591 | /* Pipe buffer operations for a buffer. */ | |
3592 | static struct pipe_buf_operations buffer_pipe_buf_ops = { | |
3593 | .can_merge = 0, | |
3594 | .map = generic_pipe_buf_map, | |
3595 | .unmap = generic_pipe_buf_unmap, | |
3596 | .confirm = generic_pipe_buf_confirm, | |
3597 | .release = buffer_pipe_buf_release, | |
3598 | .steal = buffer_pipe_buf_steal, | |
3599 | .get = buffer_pipe_buf_get, | |
3600 | }; | |
3601 | ||
3602 | /* | |
3603 | * Callback from splice_to_pipe(), if we need to release some pages | |
3604 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3605 | */ | |
3606 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3607 | { | |
3608 | struct buffer_ref *ref = | |
3609 | (struct buffer_ref *)spd->partial[i].private; | |
3610 | ||
3611 | if (--ref->ref) | |
3612 | return; | |
3613 | ||
3614 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3615 | kfree(ref); | |
3616 | spd->partial[i].private = 0; | |
3617 | } | |
3618 | ||
3619 | static ssize_t | |
3620 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3621 | struct pipe_inode_info *pipe, size_t len, | |
3622 | unsigned int flags) | |
3623 | { | |
3624 | struct ftrace_buffer_info *info = file->private_data; | |
3625 | struct partial_page partial[PIPE_BUFFERS]; | |
3626 | struct page *pages[PIPE_BUFFERS]; | |
3627 | struct splice_pipe_desc spd = { | |
3628 | .pages = pages, | |
3629 | .partial = partial, | |
3630 | .flags = flags, | |
3631 | .ops = &buffer_pipe_buf_ops, | |
3632 | .spd_release = buffer_spd_release, | |
3633 | }; | |
3634 | struct buffer_ref *ref; | |
93459c6c | 3635 | int entries, size, i; |
2cadf913 SR |
3636 | size_t ret; |
3637 | ||
93cfb3c9 LJ |
3638 | if (*ppos & (PAGE_SIZE - 1)) { |
3639 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
3640 | return -EINVAL; | |
3641 | } | |
3642 | ||
3643 | if (len & (PAGE_SIZE - 1)) { | |
3644 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
3645 | if (len < PAGE_SIZE) | |
3646 | return -EINVAL; | |
3647 | len &= PAGE_MASK; | |
3648 | } | |
3649 | ||
93459c6c SR |
3650 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
3651 | ||
3652 | for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) { | |
2cadf913 SR |
3653 | struct page *page; |
3654 | int r; | |
3655 | ||
3656 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3657 | if (!ref) | |
3658 | break; | |
3659 | ||
7267fa68 | 3660 | ref->ref = 1; |
2cadf913 SR |
3661 | ref->buffer = info->tr->buffer; |
3662 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3663 | if (!ref->page) { | |
3664 | kfree(ref); | |
3665 | break; | |
3666 | } | |
3667 | ||
3668 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 3669 | len, info->cpu, 1); |
2cadf913 SR |
3670 | if (r < 0) { |
3671 | ring_buffer_free_read_page(ref->buffer, | |
3672 | ref->page); | |
3673 | kfree(ref); | |
3674 | break; | |
3675 | } | |
3676 | ||
3677 | /* | |
3678 | * zero out any left over data, this is going to | |
3679 | * user land. | |
3680 | */ | |
3681 | size = ring_buffer_page_len(ref->page); | |
3682 | if (size < PAGE_SIZE) | |
3683 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3684 | ||
3685 | page = virt_to_page(ref->page); | |
3686 | ||
3687 | spd.pages[i] = page; | |
3688 | spd.partial[i].len = PAGE_SIZE; | |
3689 | spd.partial[i].offset = 0; | |
3690 | spd.partial[i].private = (unsigned long)ref; | |
3691 | spd.nr_pages++; | |
93cfb3c9 | 3692 | *ppos += PAGE_SIZE; |
93459c6c SR |
3693 | |
3694 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
3695 | } |
3696 | ||
3697 | spd.nr_pages = i; | |
3698 | ||
3699 | /* did we read anything? */ | |
3700 | if (!spd.nr_pages) { | |
3701 | if (flags & SPLICE_F_NONBLOCK) | |
3702 | ret = -EAGAIN; | |
3703 | else | |
3704 | ret = 0; | |
3705 | /* TODO: block */ | |
3706 | return ret; | |
3707 | } | |
3708 | ||
3709 | ret = splice_to_pipe(pipe, &spd); | |
3710 | ||
3711 | return ret; | |
3712 | } | |
3713 | ||
3714 | static const struct file_operations tracing_buffers_fops = { | |
3715 | .open = tracing_buffers_open, | |
3716 | .read = tracing_buffers_read, | |
3717 | .release = tracing_buffers_release, | |
3718 | .splice_read = tracing_buffers_splice_read, | |
3719 | .llseek = no_llseek, | |
3720 | }; | |
3721 | ||
c8d77183 SR |
3722 | static ssize_t |
3723 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
3724 | size_t count, loff_t *ppos) | |
3725 | { | |
3726 | unsigned long cpu = (unsigned long)filp->private_data; | |
3727 | struct trace_array *tr = &global_trace; | |
3728 | struct trace_seq *s; | |
3729 | unsigned long cnt; | |
3730 | ||
e4f2d10f | 3731 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 SR |
3732 | if (!s) |
3733 | return ENOMEM; | |
3734 | ||
3735 | trace_seq_init(s); | |
3736 | ||
3737 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
3738 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
3739 | ||
3740 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
3741 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
3742 | ||
3743 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
3744 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
3745 | ||
c8d77183 SR |
3746 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
3747 | ||
3748 | kfree(s); | |
3749 | ||
3750 | return count; | |
3751 | } | |
3752 | ||
3753 | static const struct file_operations tracing_stats_fops = { | |
3754 | .open = tracing_open_generic, | |
3755 | .read = tracing_stats_read, | |
3756 | }; | |
3757 | ||
bc0c38d1 SR |
3758 | #ifdef CONFIG_DYNAMIC_FTRACE |
3759 | ||
b807c3d0 SR |
3760 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3761 | { | |
3762 | return 0; | |
3763 | } | |
3764 | ||
bc0c38d1 | 3765 | static ssize_t |
b807c3d0 | 3766 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3767 | size_t cnt, loff_t *ppos) |
3768 | { | |
a26a2a27 SR |
3769 | static char ftrace_dyn_info_buffer[1024]; |
3770 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3771 | unsigned long *p = filp->private_data; |
b807c3d0 | 3772 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3773 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3774 | int r; |
3775 | ||
b807c3d0 SR |
3776 | mutex_lock(&dyn_info_mutex); |
3777 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3778 | |
a26a2a27 | 3779 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3780 | buf[r++] = '\n'; |
3781 | ||
3782 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3783 | ||
3784 | mutex_unlock(&dyn_info_mutex); | |
3785 | ||
3786 | return r; | |
bc0c38d1 SR |
3787 | } |
3788 | ||
5e2336a0 | 3789 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3790 | .open = tracing_open_generic, |
b807c3d0 | 3791 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3792 | }; |
3793 | #endif | |
3794 | ||
3795 | static struct dentry *d_tracer; | |
3796 | ||
3797 | struct dentry *tracing_init_dentry(void) | |
3798 | { | |
3799 | static int once; | |
3800 | ||
3801 | if (d_tracer) | |
3802 | return d_tracer; | |
3803 | ||
3e1f60b8 FW |
3804 | if (!debugfs_initialized()) |
3805 | return NULL; | |
3806 | ||
bc0c38d1 SR |
3807 | d_tracer = debugfs_create_dir("tracing", NULL); |
3808 | ||
3809 | if (!d_tracer && !once) { | |
3810 | once = 1; | |
3811 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3812 | return NULL; | |
3813 | } | |
3814 | ||
3815 | return d_tracer; | |
3816 | } | |
3817 | ||
b04cc6b1 FW |
3818 | static struct dentry *d_percpu; |
3819 | ||
3820 | struct dentry *tracing_dentry_percpu(void) | |
3821 | { | |
3822 | static int once; | |
3823 | struct dentry *d_tracer; | |
3824 | ||
3825 | if (d_percpu) | |
3826 | return d_percpu; | |
3827 | ||
3828 | d_tracer = tracing_init_dentry(); | |
3829 | ||
3830 | if (!d_tracer) | |
3831 | return NULL; | |
3832 | ||
3833 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
3834 | ||
3835 | if (!d_percpu && !once) { | |
3836 | once = 1; | |
3837 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
3838 | return NULL; | |
3839 | } | |
3840 | ||
3841 | return d_percpu; | |
3842 | } | |
3843 | ||
3844 | static void tracing_init_debugfs_percpu(long cpu) | |
3845 | { | |
3846 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 3847 | struct dentry *d_cpu; |
8656e7a2 FW |
3848 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ |
3849 | char cpu_dir[7]; | |
b04cc6b1 FW |
3850 | |
3851 | if (cpu > 999 || cpu < 0) | |
3852 | return; | |
3853 | ||
8656e7a2 FW |
3854 | sprintf(cpu_dir, "cpu%ld", cpu); |
3855 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
3856 | if (!d_cpu) { | |
3857 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
3858 | return; | |
3859 | } | |
b04cc6b1 | 3860 | |
8656e7a2 | 3861 | /* per cpu trace_pipe */ |
5452af66 FW |
3862 | trace_create_file("trace_pipe", 0444, d_cpu, |
3863 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
3864 | |
3865 | /* per cpu trace */ | |
5452af66 FW |
3866 | trace_create_file("trace", 0644, d_cpu, |
3867 | (void *) cpu, &tracing_fops); | |
7f96f93f | 3868 | |
5452af66 FW |
3869 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
3870 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 3871 | |
c8d77183 SR |
3872 | trace_create_file("stats", 0444, d_cpu, |
3873 | (void *) cpu, &tracing_stats_fops); | |
b04cc6b1 FW |
3874 | } |
3875 | ||
60a11774 SR |
3876 | #ifdef CONFIG_FTRACE_SELFTEST |
3877 | /* Let selftest have access to static functions in this file */ | |
3878 | #include "trace_selftest.c" | |
3879 | #endif | |
3880 | ||
577b785f SR |
3881 | struct trace_option_dentry { |
3882 | struct tracer_opt *opt; | |
3883 | struct tracer_flags *flags; | |
3884 | struct dentry *entry; | |
3885 | }; | |
3886 | ||
3887 | static ssize_t | |
3888 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3889 | loff_t *ppos) | |
3890 | { | |
3891 | struct trace_option_dentry *topt = filp->private_data; | |
3892 | char *buf; | |
3893 | ||
3894 | if (topt->flags->val & topt->opt->bit) | |
3895 | buf = "1\n"; | |
3896 | else | |
3897 | buf = "0\n"; | |
3898 | ||
3899 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3900 | } | |
3901 | ||
3902 | static ssize_t | |
3903 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3904 | loff_t *ppos) | |
3905 | { | |
3906 | struct trace_option_dentry *topt = filp->private_data; | |
3907 | unsigned long val; | |
3908 | char buf[64]; | |
3909 | int ret; | |
3910 | ||
3911 | if (cnt >= sizeof(buf)) | |
3912 | return -EINVAL; | |
3913 | ||
3914 | if (copy_from_user(&buf, ubuf, cnt)) | |
3915 | return -EFAULT; | |
3916 | ||
3917 | buf[cnt] = 0; | |
3918 | ||
3919 | ret = strict_strtoul(buf, 10, &val); | |
3920 | if (ret < 0) | |
3921 | return ret; | |
3922 | ||
3923 | ret = 0; | |
3924 | switch (val) { | |
3925 | case 0: | |
3926 | /* do nothing if already cleared */ | |
3927 | if (!(topt->flags->val & topt->opt->bit)) | |
3928 | break; | |
3929 | ||
3930 | mutex_lock(&trace_types_lock); | |
3931 | if (current_trace->set_flag) | |
3932 | ret = current_trace->set_flag(topt->flags->val, | |
3933 | topt->opt->bit, 0); | |
3934 | mutex_unlock(&trace_types_lock); | |
3935 | if (ret) | |
3936 | return ret; | |
3937 | topt->flags->val &= ~topt->opt->bit; | |
3938 | break; | |
3939 | case 1: | |
3940 | /* do nothing if already set */ | |
3941 | if (topt->flags->val & topt->opt->bit) | |
3942 | break; | |
3943 | ||
3944 | mutex_lock(&trace_types_lock); | |
3945 | if (current_trace->set_flag) | |
3946 | ret = current_trace->set_flag(topt->flags->val, | |
3947 | topt->opt->bit, 1); | |
3948 | mutex_unlock(&trace_types_lock); | |
3949 | if (ret) | |
3950 | return ret; | |
3951 | topt->flags->val |= topt->opt->bit; | |
3952 | break; | |
3953 | ||
3954 | default: | |
3955 | return -EINVAL; | |
3956 | } | |
3957 | ||
3958 | *ppos += cnt; | |
3959 | ||
3960 | return cnt; | |
3961 | } | |
3962 | ||
3963 | ||
3964 | static const struct file_operations trace_options_fops = { | |
3965 | .open = tracing_open_generic, | |
3966 | .read = trace_options_read, | |
3967 | .write = trace_options_write, | |
3968 | }; | |
3969 | ||
a8259075 SR |
3970 | static ssize_t |
3971 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3972 | loff_t *ppos) | |
3973 | { | |
3974 | long index = (long)filp->private_data; | |
3975 | char *buf; | |
3976 | ||
3977 | if (trace_flags & (1 << index)) | |
3978 | buf = "1\n"; | |
3979 | else | |
3980 | buf = "0\n"; | |
3981 | ||
3982 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3983 | } | |
3984 | ||
3985 | static ssize_t | |
3986 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3987 | loff_t *ppos) | |
3988 | { | |
3989 | long index = (long)filp->private_data; | |
3990 | char buf[64]; | |
3991 | unsigned long val; | |
3992 | int ret; | |
3993 | ||
3994 | if (cnt >= sizeof(buf)) | |
3995 | return -EINVAL; | |
3996 | ||
3997 | if (copy_from_user(&buf, ubuf, cnt)) | |
3998 | return -EFAULT; | |
3999 | ||
4000 | buf[cnt] = 0; | |
4001 | ||
4002 | ret = strict_strtoul(buf, 10, &val); | |
4003 | if (ret < 0) | |
4004 | return ret; | |
4005 | ||
f2d84b65 | 4006 | if (val != 0 && val != 1) |
a8259075 | 4007 | return -EINVAL; |
f2d84b65 | 4008 | set_tracer_flags(1 << index, val); |
a8259075 SR |
4009 | |
4010 | *ppos += cnt; | |
4011 | ||
4012 | return cnt; | |
4013 | } | |
4014 | ||
a8259075 SR |
4015 | static const struct file_operations trace_options_core_fops = { |
4016 | .open = tracing_open_generic, | |
4017 | .read = trace_options_core_read, | |
4018 | .write = trace_options_core_write, | |
4019 | }; | |
4020 | ||
5452af66 FW |
4021 | struct dentry *trace_create_file(const char *name, |
4022 | mode_t mode, | |
4023 | struct dentry *parent, | |
4024 | void *data, | |
4025 | const struct file_operations *fops) | |
4026 | { | |
4027 | struct dentry *ret; | |
4028 | ||
4029 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
4030 | if (!ret) | |
4031 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
4032 | ||
4033 | return ret; | |
4034 | } | |
4035 | ||
4036 | ||
a8259075 SR |
4037 | static struct dentry *trace_options_init_dentry(void) |
4038 | { | |
4039 | struct dentry *d_tracer; | |
4040 | static struct dentry *t_options; | |
4041 | ||
4042 | if (t_options) | |
4043 | return t_options; | |
4044 | ||
4045 | d_tracer = tracing_init_dentry(); | |
4046 | if (!d_tracer) | |
4047 | return NULL; | |
4048 | ||
4049 | t_options = debugfs_create_dir("options", d_tracer); | |
4050 | if (!t_options) { | |
4051 | pr_warning("Could not create debugfs directory 'options'\n"); | |
4052 | return NULL; | |
4053 | } | |
4054 | ||
4055 | return t_options; | |
4056 | } | |
4057 | ||
577b785f SR |
4058 | static void |
4059 | create_trace_option_file(struct trace_option_dentry *topt, | |
4060 | struct tracer_flags *flags, | |
4061 | struct tracer_opt *opt) | |
4062 | { | |
4063 | struct dentry *t_options; | |
577b785f SR |
4064 | |
4065 | t_options = trace_options_init_dentry(); | |
4066 | if (!t_options) | |
4067 | return; | |
4068 | ||
4069 | topt->flags = flags; | |
4070 | topt->opt = opt; | |
4071 | ||
5452af66 | 4072 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
4073 | &trace_options_fops); |
4074 | ||
577b785f SR |
4075 | } |
4076 | ||
4077 | static struct trace_option_dentry * | |
4078 | create_trace_option_files(struct tracer *tracer) | |
4079 | { | |
4080 | struct trace_option_dentry *topts; | |
4081 | struct tracer_flags *flags; | |
4082 | struct tracer_opt *opts; | |
4083 | int cnt; | |
4084 | ||
4085 | if (!tracer) | |
4086 | return NULL; | |
4087 | ||
4088 | flags = tracer->flags; | |
4089 | ||
4090 | if (!flags || !flags->opts) | |
4091 | return NULL; | |
4092 | ||
4093 | opts = flags->opts; | |
4094 | ||
4095 | for (cnt = 0; opts[cnt].name; cnt++) | |
4096 | ; | |
4097 | ||
0cfe8245 | 4098 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
4099 | if (!topts) |
4100 | return NULL; | |
4101 | ||
4102 | for (cnt = 0; opts[cnt].name; cnt++) | |
4103 | create_trace_option_file(&topts[cnt], flags, | |
4104 | &opts[cnt]); | |
4105 | ||
4106 | return topts; | |
4107 | } | |
4108 | ||
4109 | static void | |
4110 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
4111 | { | |
4112 | int cnt; | |
4113 | ||
4114 | if (!topts) | |
4115 | return; | |
4116 | ||
4117 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
4118 | if (topts[cnt].entry) | |
4119 | debugfs_remove(topts[cnt].entry); | |
4120 | } | |
4121 | ||
4122 | kfree(topts); | |
4123 | } | |
4124 | ||
a8259075 SR |
4125 | static struct dentry * |
4126 | create_trace_option_core_file(const char *option, long index) | |
4127 | { | |
4128 | struct dentry *t_options; | |
a8259075 SR |
4129 | |
4130 | t_options = trace_options_init_dentry(); | |
4131 | if (!t_options) | |
4132 | return NULL; | |
4133 | ||
5452af66 | 4134 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 4135 | &trace_options_core_fops); |
a8259075 SR |
4136 | } |
4137 | ||
4138 | static __init void create_trace_options_dir(void) | |
4139 | { | |
4140 | struct dentry *t_options; | |
a8259075 SR |
4141 | int i; |
4142 | ||
4143 | t_options = trace_options_init_dentry(); | |
4144 | if (!t_options) | |
4145 | return; | |
4146 | ||
5452af66 FW |
4147 | for (i = 0; trace_options[i]; i++) |
4148 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4149 | } |
4150 | ||
b5ad384e | 4151 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4152 | { |
4153 | struct dentry *d_tracer; | |
b04cc6b1 | 4154 | int cpu; |
bc0c38d1 SR |
4155 | |
4156 | d_tracer = tracing_init_dentry(); | |
4157 | ||
5452af66 FW |
4158 | trace_create_file("tracing_enabled", 0644, d_tracer, |
4159 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 4160 | |
5452af66 FW |
4161 | trace_create_file("trace_options", 0644, d_tracer, |
4162 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4163 | |
5452af66 FW |
4164 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4165 | NULL, &tracing_cpumask_fops); | |
4166 | ||
4167 | trace_create_file("trace", 0644, d_tracer, | |
4168 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 4169 | |
5452af66 FW |
4170 | trace_create_file("available_tracers", 0444, d_tracer, |
4171 | &global_trace, &show_traces_fops); | |
4172 | ||
339ae5d3 | 4173 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4174 | &global_trace, &set_tracer_fops); |
4175 | ||
5d4a9dba | 4176 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
4177 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
4178 | &tracing_max_latency, &tracing_max_lat_fops); | |
4179 | ||
4180 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4181 | &tracing_thresh, &tracing_max_lat_fops); | |
5d4a9dba | 4182 | #endif |
a8259075 | 4183 | |
339ae5d3 | 4184 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4185 | NULL, &tracing_readme_fops); |
4186 | ||
4187 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4188 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4189 | |
4190 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
4191 | &global_trace, &tracing_entries_fops); | |
4192 | ||
4193 | trace_create_file("trace_marker", 0220, d_tracer, | |
4194 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4195 | |
69abe6a5 AP |
4196 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4197 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 4198 | |
5079f326 Z |
4199 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
4200 | &trace_clock_fops); | |
4201 | ||
bc0c38d1 | 4202 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4203 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4204 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4205 | #endif |
d618b3e6 IM |
4206 | #ifdef CONFIG_SYSPROF_TRACER |
4207 | init_tracer_sysprof_debugfs(d_tracer); | |
4208 | #endif | |
b04cc6b1 | 4209 | |
5452af66 FW |
4210 | create_trace_options_dir(); |
4211 | ||
b04cc6b1 FW |
4212 | for_each_tracing_cpu(cpu) |
4213 | tracing_init_debugfs_percpu(cpu); | |
4214 | ||
b5ad384e | 4215 | return 0; |
bc0c38d1 SR |
4216 | } |
4217 | ||
3f5a54e3 SR |
4218 | static int trace_panic_handler(struct notifier_block *this, |
4219 | unsigned long event, void *unused) | |
4220 | { | |
944ac425 SR |
4221 | if (ftrace_dump_on_oops) |
4222 | ftrace_dump(); | |
3f5a54e3 SR |
4223 | return NOTIFY_OK; |
4224 | } | |
4225 | ||
4226 | static struct notifier_block trace_panic_notifier = { | |
4227 | .notifier_call = trace_panic_handler, | |
4228 | .next = NULL, | |
4229 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4230 | }; | |
4231 | ||
4232 | static int trace_die_handler(struct notifier_block *self, | |
4233 | unsigned long val, | |
4234 | void *data) | |
4235 | { | |
4236 | switch (val) { | |
4237 | case DIE_OOPS: | |
944ac425 SR |
4238 | if (ftrace_dump_on_oops) |
4239 | ftrace_dump(); | |
3f5a54e3 SR |
4240 | break; |
4241 | default: | |
4242 | break; | |
4243 | } | |
4244 | return NOTIFY_OK; | |
4245 | } | |
4246 | ||
4247 | static struct notifier_block trace_die_notifier = { | |
4248 | .notifier_call = trace_die_handler, | |
4249 | .priority = 200 | |
4250 | }; | |
4251 | ||
4252 | /* | |
4253 | * printk is set to max of 1024, we really don't need it that big. | |
4254 | * Nothing should be printing 1000 characters anyway. | |
4255 | */ | |
4256 | #define TRACE_MAX_PRINT 1000 | |
4257 | ||
4258 | /* | |
4259 | * Define here KERN_TRACE so that we have one place to modify | |
4260 | * it if we decide to change what log level the ftrace dump | |
4261 | * should be at. | |
4262 | */ | |
428aee14 | 4263 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
4264 | |
4265 | static void | |
4266 | trace_printk_seq(struct trace_seq *s) | |
4267 | { | |
4268 | /* Probably should print a warning here. */ | |
4269 | if (s->len >= 1000) | |
4270 | s->len = 1000; | |
4271 | ||
4272 | /* should be zero ended, but we are paranoid. */ | |
4273 | s->buffer[s->len] = 0; | |
4274 | ||
4275 | printk(KERN_TRACE "%s", s->buffer); | |
4276 | ||
f9520750 | 4277 | trace_seq_init(s); |
3f5a54e3 SR |
4278 | } |
4279 | ||
cf586b61 | 4280 | static void __ftrace_dump(bool disable_tracing) |
3f5a54e3 | 4281 | { |
cd891ae0 SR |
4282 | static raw_spinlock_t ftrace_dump_lock = |
4283 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
3f5a54e3 SR |
4284 | /* use static because iter can be a bit big for the stack */ |
4285 | static struct trace_iterator iter; | |
cf586b61 | 4286 | unsigned int old_userobj; |
3f5a54e3 | 4287 | static int dump_ran; |
d769041f SR |
4288 | unsigned long flags; |
4289 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4290 | |
4291 | /* only one dump */ | |
cd891ae0 SR |
4292 | local_irq_save(flags); |
4293 | __raw_spin_lock(&ftrace_dump_lock); | |
3f5a54e3 SR |
4294 | if (dump_ran) |
4295 | goto out; | |
4296 | ||
4297 | dump_ran = 1; | |
4298 | ||
0ee6b6cf | 4299 | tracing_off(); |
cf586b61 FW |
4300 | |
4301 | if (disable_tracing) | |
4302 | ftrace_kill(); | |
3f5a54e3 | 4303 | |
d769041f SR |
4304 | for_each_tracing_cpu(cpu) { |
4305 | atomic_inc(&global_trace.data[cpu]->disabled); | |
4306 | } | |
4307 | ||
cf586b61 FW |
4308 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4309 | ||
b54d3de9 TE |
4310 | /* don't look at user memory in panic mode */ |
4311 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4312 | ||
3f5a54e3 SR |
4313 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
4314 | ||
e543ad76 | 4315 | /* Simulate the iterator */ |
3f5a54e3 SR |
4316 | iter.tr = &global_trace; |
4317 | iter.trace = current_trace; | |
e543ad76 | 4318 | iter.cpu_file = TRACE_PIPE_ALL_CPU; |
3f5a54e3 SR |
4319 | |
4320 | /* | |
4321 | * We need to stop all tracing on all CPUS to read the | |
4322 | * the next buffer. This is a bit expensive, but is | |
4323 | * not done often. We fill all what we can read, | |
4324 | * and then release the locks again. | |
4325 | */ | |
4326 | ||
3f5a54e3 SR |
4327 | while (!trace_empty(&iter)) { |
4328 | ||
4329 | if (!cnt) | |
4330 | printk(KERN_TRACE "---------------------------------\n"); | |
4331 | ||
4332 | cnt++; | |
4333 | ||
4334 | /* reset all but tr, trace, and overruns */ | |
4335 | memset(&iter.seq, 0, | |
4336 | sizeof(struct trace_iterator) - | |
4337 | offsetof(struct trace_iterator, seq)); | |
4338 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4339 | iter.pos = -1; | |
4340 | ||
4341 | if (find_next_entry_inc(&iter) != NULL) { | |
74e7ff8c LJ |
4342 | int ret; |
4343 | ||
4344 | ret = print_trace_line(&iter); | |
4345 | if (ret != TRACE_TYPE_NO_CONSUME) | |
4346 | trace_consume(&iter); | |
3f5a54e3 SR |
4347 | } |
4348 | ||
4349 | trace_printk_seq(&iter.seq); | |
4350 | } | |
4351 | ||
4352 | if (!cnt) | |
4353 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4354 | else | |
4355 | printk(KERN_TRACE "---------------------------------\n"); | |
4356 | ||
cf586b61 FW |
4357 | /* Re-enable tracing if requested */ |
4358 | if (!disable_tracing) { | |
4359 | trace_flags |= old_userobj; | |
4360 | ||
4361 | for_each_tracing_cpu(cpu) { | |
4362 | atomic_dec(&global_trace.data[cpu]->disabled); | |
4363 | } | |
4364 | tracing_on(); | |
4365 | } | |
4366 | ||
3f5a54e3 | 4367 | out: |
cd891ae0 SR |
4368 | __raw_spin_unlock(&ftrace_dump_lock); |
4369 | local_irq_restore(flags); | |
3f5a54e3 SR |
4370 | } |
4371 | ||
cf586b61 FW |
4372 | /* By default: disable tracing after the dump */ |
4373 | void ftrace_dump(void) | |
4374 | { | |
4375 | __ftrace_dump(true); | |
4376 | } | |
4377 | ||
3928a8a2 | 4378 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4379 | { |
73c5162a | 4380 | int ring_buf_size; |
4c11d7ae | 4381 | int i; |
9e01c1b7 | 4382 | int ret = -ENOMEM; |
4c11d7ae | 4383 | |
9e01c1b7 RR |
4384 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4385 | goto out; | |
4386 | ||
4387 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4388 | goto out_free_buffer_mask; | |
4c11d7ae | 4389 | |
79f55997 | 4390 | if (!zalloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) |
b04cc6b1 FW |
4391 | goto out_free_tracing_cpumask; |
4392 | ||
73c5162a SR |
4393 | /* To save memory, keep the ring buffer size to its minimum */ |
4394 | if (ring_buffer_expanded) | |
4395 | ring_buf_size = trace_buf_size; | |
4396 | else | |
4397 | ring_buf_size = 1; | |
4398 | ||
9e01c1b7 RR |
4399 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4400 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
4401 | ||
4402 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
73c5162a | 4403 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4404 | TRACE_BUFFER_FLAGS); |
4405 | if (!global_trace.buffer) { | |
4406 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4407 | WARN_ON(1); | |
9e01c1b7 | 4408 | goto out_free_cpumask; |
4c11d7ae | 4409 | } |
3928a8a2 | 4410 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4411 | |
9e01c1b7 | 4412 | |
4c11d7ae | 4413 | #ifdef CONFIG_TRACER_MAX_TRACE |
73c5162a | 4414 | max_tr.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4415 | TRACE_BUFFER_FLAGS); |
4416 | if (!max_tr.buffer) { | |
4417 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4418 | WARN_ON(1); | |
4419 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4420 | goto out_free_cpumask; |
4c11d7ae | 4421 | } |
3928a8a2 SR |
4422 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
4423 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 4424 | #endif |
ab46428c | 4425 | |
4c11d7ae | 4426 | /* Allocate the first page for all buffers */ |
ab46428c | 4427 | for_each_tracing_cpu(i) { |
566b0aaf | 4428 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
9705f69e | 4429 | max_tr.data[i] = &per_cpu(max_tr_data, i); |
4c11d7ae | 4430 | } |
bc0c38d1 | 4431 | |
bc0c38d1 SR |
4432 | trace_init_cmdlines(); |
4433 | ||
43a15386 | 4434 | register_tracer(&nop_trace); |
79fb0768 | 4435 | current_trace = &nop_trace; |
b5ad384e FW |
4436 | #ifdef CONFIG_BOOT_TRACER |
4437 | register_tracer(&boot_tracer); | |
b5ad384e | 4438 | #endif |
60a11774 SR |
4439 | /* All seems OK, enable tracing */ |
4440 | tracing_disabled = 0; | |
3928a8a2 | 4441 | |
3f5a54e3 SR |
4442 | atomic_notifier_chain_register(&panic_notifier_list, |
4443 | &trace_panic_notifier); | |
4444 | ||
4445 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4446 | |
4447 | return 0; | |
3f5a54e3 | 4448 | |
9e01c1b7 | 4449 | out_free_cpumask: |
b04cc6b1 FW |
4450 | free_cpumask_var(tracing_reader_cpumask); |
4451 | out_free_tracing_cpumask: | |
9e01c1b7 RR |
4452 | free_cpumask_var(tracing_cpumask); |
4453 | out_free_buffer_mask: | |
4454 | free_cpumask_var(tracing_buffer_mask); | |
4455 | out: | |
4456 | return ret; | |
bc0c38d1 | 4457 | } |
b2821ae6 SR |
4458 | |
4459 | __init static int clear_boot_tracer(void) | |
4460 | { | |
4461 | /* | |
4462 | * The default tracer at boot buffer is an init section. | |
4463 | * This function is called in lateinit. If we did not | |
4464 | * find the boot tracer, then clear it out, to prevent | |
4465 | * later registration from accessing the buffer that is | |
4466 | * about to be freed. | |
4467 | */ | |
4468 | if (!default_bootup_tracer) | |
4469 | return 0; | |
4470 | ||
4471 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4472 | default_bootup_tracer); | |
4473 | default_bootup_tracer = NULL; | |
4474 | ||
4475 | return 0; | |
4476 | } | |
4477 | ||
b5ad384e FW |
4478 | early_initcall(tracer_alloc_buffers); |
4479 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4480 | late_initcall(clear_boot_tracer); |