Commit | Line | Data |
---|---|---|
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 | |
5e5bf483 | 89 | DEFINE_PER_CPU(local_t, ftrace_cpu_disabled); |
d769041f SR |
90 | |
91 | static inline void ftrace_disable_cpu(void) | |
92 | { | |
93 | preempt_disable(); | |
94 | local_inc(&__get_cpu_var(ftrace_cpu_disabled)); | |
95 | } | |
96 | ||
97 | static inline void ftrace_enable_cpu(void) | |
98 | { | |
99 | local_dec(&__get_cpu_var(ftrace_cpu_disabled)); | |
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 | ||
128 | #define BOOTUP_TRACER_SIZE 100 | |
129 | static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata; | |
130 | static char *default_bootup_tracer; | |
d9e54076 PZ |
131 | |
132 | static int __init set_ftrace(char *str) | |
133 | { | |
b2821ae6 SR |
134 | strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); |
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 | ||
206 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
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 SR |
243 | |
244 | /* | |
245 | * max_tracer_type_len is used to simplify the allocating of | |
246 | * buffers to read userspace tracer names. We keep track of | |
247 | * the longest tracer name registered. | |
248 | */ | |
bc0c38d1 SR |
249 | static int max_tracer_type_len; |
250 | ||
4fcdae83 SR |
251 | /* |
252 | * trace_types_lock is used to protect the trace_types list. | |
253 | * This lock is also used to keep user access serialized. | |
254 | * Accesses from userspace will grab this lock while userspace | |
255 | * activities happen inside the kernel. | |
256 | */ | |
bc0c38d1 | 257 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
258 | |
259 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
260 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
261 | ||
ee6bce52 | 262 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 263 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a SR |
264 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
265 | TRACE_ITER_GRAPH_TIME; | |
4e655519 | 266 | |
b8de7bd1 SR |
267 | static int trace_stop_count; |
268 | static DEFINE_SPINLOCK(tracing_start_lock); | |
269 | ||
4fcdae83 SR |
270 | /** |
271 | * trace_wake_up - wake up tasks waiting for trace input | |
272 | * | |
273 | * Simply wakes up any task that is blocked on the trace_wait | |
274 | * queue. These is used with trace_poll for tasks polling the trace. | |
275 | */ | |
4e655519 IM |
276 | void trace_wake_up(void) |
277 | { | |
017730c1 IM |
278 | /* |
279 | * The runqueue_is_locked() can fail, but this is the best we | |
280 | * have for now: | |
281 | */ | |
282 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
283 | wake_up(&trace_wait); |
284 | } | |
bc0c38d1 | 285 | |
3928a8a2 | 286 | static int __init set_buf_size(char *str) |
bc0c38d1 | 287 | { |
3928a8a2 | 288 | unsigned long buf_size; |
c6caeeb1 | 289 | |
bc0c38d1 SR |
290 | if (!str) |
291 | return 0; | |
9d612bef | 292 | buf_size = memparse(str, &str); |
c6caeeb1 | 293 | /* nr_entries can not be zero */ |
9d612bef | 294 | if (buf_size == 0) |
c6caeeb1 | 295 | return 0; |
3928a8a2 | 296 | trace_buf_size = buf_size; |
bc0c38d1 SR |
297 | return 1; |
298 | } | |
3928a8a2 | 299 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 300 | |
57f50be1 SR |
301 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
302 | { | |
303 | return nsecs / 1000; | |
304 | } | |
305 | ||
4fcdae83 | 306 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
307 | static const char *trace_options[] = { |
308 | "print-parent", | |
309 | "sym-offset", | |
310 | "sym-addr", | |
311 | "verbose", | |
f9896bf3 | 312 | "raw", |
5e3ca0ec | 313 | "hex", |
cb0f12aa | 314 | "bin", |
2a2cc8f7 | 315 | "block", |
86387f7e | 316 | "stacktrace", |
4ac3ba41 | 317 | "sched-tree", |
5e1607a0 | 318 | "trace_printk", |
b2a866f9 | 319 | "ftrace_preempt", |
9f029e83 | 320 | "branch", |
12ef7d44 | 321 | "annotate", |
02b67518 | 322 | "userstacktrace", |
b54d3de9 | 323 | "sym-userobj", |
66896a85 | 324 | "printk-msg-only", |
c4a8e8be | 325 | "context-info", |
c032ef64 | 326 | "latency-format", |
be6f164a | 327 | "sleep-time", |
a2a16d6a | 328 | "graph-time", |
bc0c38d1 SR |
329 | NULL |
330 | }; | |
331 | ||
5079f326 Z |
332 | static struct { |
333 | u64 (*func)(void); | |
334 | const char *name; | |
335 | } trace_clocks[] = { | |
336 | { trace_clock_local, "local" }, | |
337 | { trace_clock_global, "global" }, | |
338 | }; | |
339 | ||
340 | int trace_clock_id; | |
341 | ||
b63f39ea | 342 | /* |
343 | * trace_parser_get_init - gets the buffer for trace parser | |
344 | */ | |
345 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
346 | { | |
347 | memset(parser, 0, sizeof(*parser)); | |
348 | ||
349 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
350 | if (!parser->buffer) | |
351 | return 1; | |
352 | ||
353 | parser->size = size; | |
354 | return 0; | |
355 | } | |
356 | ||
357 | /* | |
358 | * trace_parser_put - frees the buffer for trace parser | |
359 | */ | |
360 | void trace_parser_put(struct trace_parser *parser) | |
361 | { | |
362 | kfree(parser->buffer); | |
363 | } | |
364 | ||
365 | /* | |
366 | * trace_get_user - reads the user input string separated by space | |
367 | * (matched by isspace(ch)) | |
368 | * | |
369 | * For each string found the 'struct trace_parser' is updated, | |
370 | * and the function returns. | |
371 | * | |
372 | * Returns number of bytes read. | |
373 | * | |
374 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
375 | */ | |
376 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
377 | size_t cnt, loff_t *ppos) | |
378 | { | |
379 | char ch; | |
380 | size_t read = 0; | |
381 | ssize_t ret; | |
382 | ||
383 | if (!*ppos) | |
384 | trace_parser_clear(parser); | |
385 | ||
386 | ret = get_user(ch, ubuf++); | |
387 | if (ret) | |
388 | goto out; | |
389 | ||
390 | read++; | |
391 | cnt--; | |
392 | ||
393 | /* | |
394 | * The parser is not finished with the last write, | |
395 | * continue reading the user input without skipping spaces. | |
396 | */ | |
397 | if (!parser->cont) { | |
398 | /* skip white space */ | |
399 | while (cnt && isspace(ch)) { | |
400 | ret = get_user(ch, ubuf++); | |
401 | if (ret) | |
402 | goto out; | |
403 | read++; | |
404 | cnt--; | |
405 | } | |
406 | ||
407 | /* only spaces were written */ | |
408 | if (isspace(ch)) { | |
409 | *ppos += read; | |
410 | ret = read; | |
411 | goto out; | |
412 | } | |
413 | ||
414 | parser->idx = 0; | |
415 | } | |
416 | ||
417 | /* read the non-space input */ | |
418 | while (cnt && !isspace(ch)) { | |
419 | if (parser->idx < parser->size) | |
420 | parser->buffer[parser->idx++] = ch; | |
421 | else { | |
422 | ret = -EINVAL; | |
423 | goto out; | |
424 | } | |
425 | ret = get_user(ch, ubuf++); | |
426 | if (ret) | |
427 | goto out; | |
428 | read++; | |
429 | cnt--; | |
430 | } | |
431 | ||
432 | /* We either got finished input or we have to wait for another call. */ | |
433 | if (isspace(ch)) { | |
434 | parser->buffer[parser->idx] = 0; | |
435 | parser->cont = false; | |
436 | } else { | |
437 | parser->cont = true; | |
438 | parser->buffer[parser->idx++] = ch; | |
439 | } | |
440 | ||
441 | *ppos += read; | |
442 | ret = read; | |
443 | ||
444 | out: | |
445 | return ret; | |
446 | } | |
447 | ||
6c6c2796 PP |
448 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
449 | { | |
450 | int len; | |
451 | int ret; | |
452 | ||
2dc5d12b SR |
453 | if (!cnt) |
454 | return 0; | |
455 | ||
6c6c2796 PP |
456 | if (s->len <= s->readpos) |
457 | return -EBUSY; | |
458 | ||
459 | len = s->len - s->readpos; | |
460 | if (cnt > len) | |
461 | cnt = len; | |
462 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 463 | if (ret == cnt) |
6c6c2796 PP |
464 | return -EFAULT; |
465 | ||
2dc5d12b SR |
466 | cnt -= ret; |
467 | ||
e74da523 | 468 | s->readpos += cnt; |
6c6c2796 | 469 | return cnt; |
214023c3 SR |
470 | } |
471 | ||
b8b94265 | 472 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
473 | { |
474 | int len; | |
475 | void *ret; | |
476 | ||
477 | if (s->len <= s->readpos) | |
478 | return -EBUSY; | |
479 | ||
480 | len = s->len - s->readpos; | |
481 | if (cnt > len) | |
482 | cnt = len; | |
483 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
484 | if (!ret) | |
485 | return -EFAULT; | |
486 | ||
e74da523 | 487 | s->readpos += cnt; |
3c56819b EGM |
488 | return cnt; |
489 | } | |
490 | ||
5d4a9dba SR |
491 | /* |
492 | * ftrace_max_lock is used to protect the swapping of buffers | |
493 | * when taking a max snapshot. The buffers themselves are | |
494 | * protected by per_cpu spinlocks. But the action of the swap | |
495 | * needs its own lock. | |
496 | * | |
497 | * This is defined as a raw_spinlock_t in order to help | |
498 | * with performance when lockdep debugging is enabled. | |
499 | * | |
500 | * It is also used in other places outside the update_max_tr | |
501 | * so it needs to be defined outside of the | |
502 | * CONFIG_TRACER_MAX_TRACE. | |
503 | */ | |
504 | static raw_spinlock_t ftrace_max_lock = | |
505 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
506 | ||
507 | #ifdef CONFIG_TRACER_MAX_TRACE | |
508 | unsigned long __read_mostly tracing_max_latency; | |
509 | unsigned long __read_mostly tracing_thresh; | |
510 | ||
511 | /* | |
512 | * Copy the new maximum trace into the separate maximum-trace | |
513 | * structure. (this way the maximum trace is permanently saved, | |
514 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
515 | */ | |
516 | static void | |
517 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
518 | { | |
519 | struct trace_array_cpu *data = tr->data[cpu]; | |
8248ac05 | 520 | struct trace_array_cpu *max_data = tr->data[cpu]; |
5d4a9dba SR |
521 | |
522 | max_tr.cpu = cpu; | |
523 | max_tr.time_start = data->preempt_timestamp; | |
524 | ||
8248ac05 SR |
525 | max_data = max_tr.data[cpu]; |
526 | max_data->saved_latency = tracing_max_latency; | |
527 | max_data->critical_start = data->critical_start; | |
528 | max_data->critical_end = data->critical_end; | |
5d4a9dba SR |
529 | |
530 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
8248ac05 SR |
531 | max_data->pid = tsk->pid; |
532 | max_data->uid = task_uid(tsk); | |
533 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
534 | max_data->policy = tsk->policy; | |
535 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
536 | |
537 | /* record this tasks comm */ | |
538 | tracing_record_cmdline(tsk); | |
539 | } | |
540 | ||
4fcdae83 SR |
541 | /** |
542 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
543 | * @tr: tracer | |
544 | * @tsk: the task with the latency | |
545 | * @cpu: The cpu that initiated the trace. | |
546 | * | |
547 | * Flip the buffers between the @tr and the max_tr and record information | |
548 | * about which task was the cause of this latency. | |
549 | */ | |
e309b41d | 550 | void |
bc0c38d1 SR |
551 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
552 | { | |
3928a8a2 | 553 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 554 | |
b8de7bd1 SR |
555 | if (trace_stop_count) |
556 | return; | |
557 | ||
4c11d7ae | 558 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 559 | __raw_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
560 | |
561 | tr->buffer = max_tr.buffer; | |
562 | max_tr.buffer = buf; | |
563 | ||
bc0c38d1 | 564 | __update_max_tr(tr, tsk, cpu); |
92205c23 | 565 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
566 | } |
567 | ||
568 | /** | |
569 | * update_max_tr_single - only copy one trace over, and reset the rest | |
570 | * @tr - tracer | |
571 | * @tsk - task with the latency | |
572 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
573 | * |
574 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 575 | */ |
e309b41d | 576 | void |
bc0c38d1 SR |
577 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
578 | { | |
3928a8a2 | 579 | int ret; |
bc0c38d1 | 580 | |
b8de7bd1 SR |
581 | if (trace_stop_count) |
582 | return; | |
583 | ||
4c11d7ae | 584 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 585 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 586 | |
d769041f SR |
587 | ftrace_disable_cpu(); |
588 | ||
3928a8a2 SR |
589 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); |
590 | ||
e8165dbb SR |
591 | if (ret == -EBUSY) { |
592 | /* | |
593 | * We failed to swap the buffer due to a commit taking | |
594 | * place on this CPU. We fail to record, but we reset | |
595 | * the max trace buffer (no one writes directly to it) | |
596 | * and flag that it failed. | |
597 | */ | |
598 | trace_array_printk(&max_tr, _THIS_IP_, | |
599 | "Failed to swap buffers due to commit in progress\n"); | |
600 | } | |
601 | ||
d769041f SR |
602 | ftrace_enable_cpu(); |
603 | ||
e8165dbb | 604 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
605 | |
606 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 607 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 608 | } |
5d4a9dba | 609 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 610 | |
4fcdae83 SR |
611 | /** |
612 | * register_tracer - register a tracer with the ftrace system. | |
613 | * @type - the plugin for the tracer | |
614 | * | |
615 | * Register a new plugin tracer. | |
616 | */ | |
bc0c38d1 | 617 | int register_tracer(struct tracer *type) |
e7669b8e HE |
618 | __releases(kernel_lock) |
619 | __acquires(kernel_lock) | |
bc0c38d1 SR |
620 | { |
621 | struct tracer *t; | |
622 | int len; | |
623 | int ret = 0; | |
624 | ||
625 | if (!type->name) { | |
626 | pr_info("Tracer must have a name\n"); | |
627 | return -1; | |
628 | } | |
629 | ||
86fa2f60 IM |
630 | /* |
631 | * When this gets called we hold the BKL which means that | |
632 | * preemption is disabled. Various trace selftests however | |
633 | * need to disable and enable preemption for successful tests. | |
634 | * So we drop the BKL here and grab it after the tests again. | |
635 | */ | |
636 | unlock_kernel(); | |
bc0c38d1 | 637 | mutex_lock(&trace_types_lock); |
86fa2f60 | 638 | |
8e1b82e0 FW |
639 | tracing_selftest_running = true; |
640 | ||
bc0c38d1 SR |
641 | for (t = trace_types; t; t = t->next) { |
642 | if (strcmp(type->name, t->name) == 0) { | |
643 | /* already found */ | |
644 | pr_info("Trace %s already registered\n", | |
645 | type->name); | |
646 | ret = -1; | |
647 | goto out; | |
648 | } | |
649 | } | |
650 | ||
adf9f195 FW |
651 | if (!type->set_flag) |
652 | type->set_flag = &dummy_set_flag; | |
653 | if (!type->flags) | |
654 | type->flags = &dummy_tracer_flags; | |
655 | else | |
656 | if (!type->flags->opts) | |
657 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
658 | if (!type->wait_pipe) |
659 | type->wait_pipe = default_wait_pipe; | |
660 | ||
adf9f195 | 661 | |
60a11774 | 662 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 663 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 664 | struct tracer *saved_tracer = current_trace; |
60a11774 | 665 | struct trace_array *tr = &global_trace; |
ff32504f | 666 | |
60a11774 SR |
667 | /* |
668 | * Run a selftest on this tracer. | |
669 | * Here we reset the trace buffer, and set the current | |
670 | * tracer to be this tracer. The tracer can then run some | |
671 | * internal tracing to verify that everything is in order. | |
672 | * If we fail, we do not register this tracer. | |
673 | */ | |
76f0d073 | 674 | tracing_reset_online_cpus(tr); |
86fa2f60 | 675 | |
60a11774 | 676 | current_trace = type; |
60a11774 SR |
677 | /* the test is responsible for initializing and enabling */ |
678 | pr_info("Testing tracer %s: ", type->name); | |
679 | ret = type->selftest(type, tr); | |
680 | /* the test is responsible for resetting too */ | |
681 | current_trace = saved_tracer; | |
60a11774 SR |
682 | if (ret) { |
683 | printk(KERN_CONT "FAILED!\n"); | |
684 | goto out; | |
685 | } | |
1d4db00a | 686 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 687 | tracing_reset_online_cpus(tr); |
86fa2f60 | 688 | |
60a11774 SR |
689 | printk(KERN_CONT "PASSED\n"); |
690 | } | |
691 | #endif | |
692 | ||
bc0c38d1 SR |
693 | type->next = trace_types; |
694 | trace_types = type; | |
695 | len = strlen(type->name); | |
696 | if (len > max_tracer_type_len) | |
697 | max_tracer_type_len = len; | |
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 | ||
706 | if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE)) | |
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; | |
728 | int len; | |
729 | ||
730 | mutex_lock(&trace_types_lock); | |
731 | for (t = &trace_types; *t; t = &(*t)->next) { | |
732 | if (*t == type) | |
733 | goto found; | |
734 | } | |
735 | pr_info("Trace %s not registered\n", type->name); | |
736 | goto out; | |
737 | ||
738 | found: | |
739 | *t = (*t)->next; | |
b5db03c4 ACM |
740 | |
741 | if (type == current_trace && tracer_enabled) { | |
742 | tracer_enabled = 0; | |
743 | tracing_stop(); | |
744 | if (current_trace->stop) | |
745 | current_trace->stop(&global_trace); | |
746 | current_trace = &nop_trace; | |
747 | } | |
748 | ||
bc0c38d1 SR |
749 | if (strlen(type->name) != max_tracer_type_len) |
750 | goto out; | |
751 | ||
752 | max_tracer_type_len = 0; | |
753 | for (t = &trace_types; *t; t = &(*t)->next) { | |
754 | len = strlen((*t)->name); | |
755 | if (len > max_tracer_type_len) | |
756 | max_tracer_type_len = len; | |
757 | } | |
758 | out: | |
759 | mutex_unlock(&trace_types_lock); | |
760 | } | |
761 | ||
f633903a | 762 | static void __tracing_reset(struct trace_array *tr, int cpu) |
bc0c38d1 | 763 | { |
d769041f | 764 | ftrace_disable_cpu(); |
3928a8a2 | 765 | ring_buffer_reset_cpu(tr->buffer, cpu); |
d769041f | 766 | ftrace_enable_cpu(); |
bc0c38d1 SR |
767 | } |
768 | ||
f633903a SR |
769 | void tracing_reset(struct trace_array *tr, int cpu) |
770 | { | |
771 | struct ring_buffer *buffer = tr->buffer; | |
772 | ||
773 | ring_buffer_record_disable(buffer); | |
774 | ||
775 | /* Make sure all commits have finished */ | |
776 | synchronize_sched(); | |
777 | __tracing_reset(tr, cpu); | |
778 | ||
779 | ring_buffer_record_enable(buffer); | |
780 | } | |
781 | ||
213cc060 PE |
782 | void tracing_reset_online_cpus(struct trace_array *tr) |
783 | { | |
621968cd | 784 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
785 | int cpu; |
786 | ||
621968cd SR |
787 | ring_buffer_record_disable(buffer); |
788 | ||
789 | /* Make sure all commits have finished */ | |
790 | synchronize_sched(); | |
791 | ||
213cc060 PE |
792 | tr->time_start = ftrace_now(tr->cpu); |
793 | ||
794 | for_each_online_cpu(cpu) | |
f633903a | 795 | __tracing_reset(tr, cpu); |
621968cd SR |
796 | |
797 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
798 | } |
799 | ||
9456f0fa SR |
800 | void tracing_reset_current(int cpu) |
801 | { | |
802 | tracing_reset(&global_trace, cpu); | |
803 | } | |
804 | ||
805 | void tracing_reset_current_online_cpus(void) | |
806 | { | |
807 | tracing_reset_online_cpus(&global_trace); | |
808 | } | |
809 | ||
bc0c38d1 | 810 | #define SAVED_CMDLINES 128 |
2c7eea4c | 811 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
812 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
813 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
814 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
815 | static int cmdline_idx; | |
efed792d | 816 | static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; |
25b0b44a | 817 | |
25b0b44a | 818 | /* temporary disable recording */ |
4fd27358 | 819 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
820 | |
821 | static void trace_init_cmdlines(void) | |
822 | { | |
2c7eea4c TG |
823 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
824 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
825 | cmdline_idx = 0; |
826 | } | |
827 | ||
b5130b1e CE |
828 | int is_tracing_stopped(void) |
829 | { | |
830 | return trace_stop_count; | |
831 | } | |
832 | ||
69bb54ec SR |
833 | /** |
834 | * ftrace_off_permanent - disable all ftrace code permanently | |
835 | * | |
836 | * This should only be called when a serious anomally has | |
837 | * been detected. This will turn off the function tracing, | |
838 | * ring buffers, and other tracing utilites. It takes no | |
839 | * locks and can be called from any context. | |
840 | */ | |
841 | void ftrace_off_permanent(void) | |
842 | { | |
843 | tracing_disabled = 1; | |
844 | ftrace_stop(); | |
845 | tracing_off_permanent(); | |
846 | } | |
847 | ||
0f048701 SR |
848 | /** |
849 | * tracing_start - quick start of the tracer | |
850 | * | |
851 | * If tracing is enabled but was stopped by tracing_stop, | |
852 | * this will start the tracer back up. | |
853 | */ | |
854 | void tracing_start(void) | |
855 | { | |
856 | struct ring_buffer *buffer; | |
857 | unsigned long flags; | |
858 | ||
859 | if (tracing_disabled) | |
860 | return; | |
861 | ||
862 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
863 | if (--trace_stop_count) { |
864 | if (trace_stop_count < 0) { | |
865 | /* Someone screwed up their debugging */ | |
866 | WARN_ON_ONCE(1); | |
867 | trace_stop_count = 0; | |
868 | } | |
0f048701 SR |
869 | goto out; |
870 | } | |
871 | ||
872 | ||
873 | buffer = global_trace.buffer; | |
874 | if (buffer) | |
875 | ring_buffer_record_enable(buffer); | |
876 | ||
877 | buffer = max_tr.buffer; | |
878 | if (buffer) | |
879 | ring_buffer_record_enable(buffer); | |
880 | ||
881 | ftrace_start(); | |
882 | out: | |
883 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
884 | } | |
885 | ||
886 | /** | |
887 | * tracing_stop - quick stop of the tracer | |
888 | * | |
889 | * Light weight way to stop tracing. Use in conjunction with | |
890 | * tracing_start. | |
891 | */ | |
892 | void tracing_stop(void) | |
893 | { | |
894 | struct ring_buffer *buffer; | |
895 | unsigned long flags; | |
896 | ||
897 | ftrace_stop(); | |
898 | spin_lock_irqsave(&tracing_start_lock, flags); | |
899 | if (trace_stop_count++) | |
900 | goto out; | |
901 | ||
902 | buffer = global_trace.buffer; | |
903 | if (buffer) | |
904 | ring_buffer_record_disable(buffer); | |
905 | ||
906 | buffer = max_tr.buffer; | |
907 | if (buffer) | |
908 | ring_buffer_record_disable(buffer); | |
909 | ||
910 | out: | |
911 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
912 | } | |
913 | ||
e309b41d | 914 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 915 | |
e309b41d | 916 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 917 | { |
a635cf04 | 918 | unsigned pid, idx; |
bc0c38d1 SR |
919 | |
920 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
921 | return; | |
922 | ||
923 | /* | |
924 | * It's not the end of the world if we don't get | |
925 | * the lock, but we also don't want to spin | |
926 | * nor do we want to disable interrupts, | |
927 | * so if we miss here, then better luck next time. | |
928 | */ | |
efed792d | 929 | if (!__raw_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
930 | return; |
931 | ||
932 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 933 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
934 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
935 | ||
a635cf04 CE |
936 | /* |
937 | * Check whether the cmdline buffer at idx has a pid | |
938 | * mapped. We are going to overwrite that entry so we | |
939 | * need to clear the map_pid_to_cmdline. Otherwise we | |
940 | * would read the new comm for the old pid. | |
941 | */ | |
942 | pid = map_cmdline_to_pid[idx]; | |
943 | if (pid != NO_CMDLINE_MAP) | |
944 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 945 | |
a635cf04 | 946 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
947 | map_pid_to_cmdline[tsk->pid] = idx; |
948 | ||
949 | cmdline_idx = idx; | |
950 | } | |
951 | ||
952 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
953 | ||
efed792d | 954 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
955 | } |
956 | ||
4ca53085 | 957 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 958 | { |
bc0c38d1 SR |
959 | unsigned map; |
960 | ||
4ca53085 SR |
961 | if (!pid) { |
962 | strcpy(comm, "<idle>"); | |
963 | return; | |
964 | } | |
bc0c38d1 | 965 | |
4ca53085 SR |
966 | if (pid > PID_MAX_DEFAULT) { |
967 | strcpy(comm, "<...>"); | |
968 | return; | |
969 | } | |
bc0c38d1 | 970 | |
5b6045a9 | 971 | preempt_disable(); |
4ca53085 | 972 | __raw_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 973 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
974 | if (map != NO_CMDLINE_MAP) |
975 | strcpy(comm, saved_cmdlines[map]); | |
976 | else | |
977 | strcpy(comm, "<...>"); | |
bc0c38d1 | 978 | |
4ca53085 | 979 | __raw_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 980 | preempt_enable(); |
bc0c38d1 SR |
981 | } |
982 | ||
e309b41d | 983 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 984 | { |
18aecd36 TG |
985 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
986 | !tracing_is_on()) | |
bc0c38d1 SR |
987 | return; |
988 | ||
989 | trace_save_cmdline(tsk); | |
990 | } | |
991 | ||
45dcd8b8 | 992 | void |
38697053 SR |
993 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
994 | int pc) | |
bc0c38d1 SR |
995 | { |
996 | struct task_struct *tsk = current; | |
bc0c38d1 | 997 | |
777e208d SR |
998 | entry->preempt_count = pc & 0xff; |
999 | entry->pid = (tsk) ? tsk->pid : 0; | |
637e7e86 | 1000 | entry->lock_depth = (tsk) ? tsk->lock_depth : 0; |
777e208d | 1001 | entry->flags = |
9244489a | 1002 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1003 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1004 | #else |
1005 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1006 | #endif | |
bc0c38d1 SR |
1007 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1008 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1009 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1010 | } | |
f413cdb8 | 1011 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1012 | |
e77405ad SR |
1013 | struct ring_buffer_event * |
1014 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1015 | int type, | |
1016 | unsigned long len, | |
1017 | unsigned long flags, int pc) | |
51a763dd ACM |
1018 | { |
1019 | struct ring_buffer_event *event; | |
1020 | ||
e77405ad | 1021 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1022 | if (event != NULL) { |
1023 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1024 | ||
1025 | tracing_generic_entry_update(ent, flags, pc); | |
1026 | ent->type = type; | |
1027 | } | |
1028 | ||
1029 | return event; | |
1030 | } | |
51a763dd | 1031 | |
e77405ad SR |
1032 | static inline void |
1033 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1034 | struct ring_buffer_event *event, | |
1035 | unsigned long flags, int pc, | |
1036 | int wake) | |
51a763dd | 1037 | { |
e77405ad | 1038 | ring_buffer_unlock_commit(buffer, event); |
51a763dd | 1039 | |
e77405ad SR |
1040 | ftrace_trace_stack(buffer, flags, 6, pc); |
1041 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1042 | |
1043 | if (wake) | |
1044 | trace_wake_up(); | |
1045 | } | |
1046 | ||
e77405ad SR |
1047 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1048 | struct ring_buffer_event *event, | |
1049 | unsigned long flags, int pc) | |
07edf712 | 1050 | { |
e77405ad | 1051 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
51a763dd ACM |
1052 | } |
1053 | ||
ef5580d0 | 1054 | struct ring_buffer_event * |
e77405ad SR |
1055 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1056 | int type, unsigned long len, | |
ef5580d0 SR |
1057 | unsigned long flags, int pc) |
1058 | { | |
e77405ad SR |
1059 | *current_rb = global_trace.buffer; |
1060 | return trace_buffer_lock_reserve(*current_rb, | |
ef5580d0 SR |
1061 | type, len, flags, pc); |
1062 | } | |
94487d6d | 1063 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1064 | |
e77405ad SR |
1065 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1066 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1067 | unsigned long flags, int pc) |
1068 | { | |
e77405ad | 1069 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
07edf712 | 1070 | } |
94487d6d | 1071 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1072 | |
e77405ad SR |
1073 | void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer, |
1074 | struct ring_buffer_event *event, | |
1075 | unsigned long flags, int pc) | |
07edf712 | 1076 | { |
e77405ad | 1077 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 0); |
77d9f465 | 1078 | } |
94487d6d | 1079 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 | 1080 | |
e77405ad SR |
1081 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1082 | struct ring_buffer_event *event) | |
77d9f465 | 1083 | { |
e77405ad | 1084 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1085 | } |
12acd473 | 1086 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1087 | |
e309b41d | 1088 | void |
7be42151 | 1089 | trace_function(struct trace_array *tr, |
38697053 SR |
1090 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1091 | int pc) | |
bc0c38d1 | 1092 | { |
e1112b4d | 1093 | struct ftrace_event_call *call = &event_function; |
e77405ad | 1094 | struct ring_buffer *buffer = tr->buffer; |
3928a8a2 | 1095 | struct ring_buffer_event *event; |
777e208d | 1096 | struct ftrace_entry *entry; |
bc0c38d1 | 1097 | |
d769041f SR |
1098 | /* If we are reading the ring buffer, don't trace */ |
1099 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
1100 | return; | |
1101 | ||
e77405ad | 1102 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1103 | flags, pc); |
3928a8a2 SR |
1104 | if (!event) |
1105 | return; | |
1106 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1107 | entry->ip = ip; |
1108 | entry->parent_ip = parent_ip; | |
e1112b4d | 1109 | |
e77405ad SR |
1110 | if (!filter_check_discard(call, entry, buffer, event)) |
1111 | ring_buffer_unlock_commit(buffer, event); | |
bc0c38d1 SR |
1112 | } |
1113 | ||
e309b41d | 1114 | void |
2e0f5761 | 1115 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1116 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1117 | int pc) | |
2e0f5761 IM |
1118 | { |
1119 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1120 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1121 | } |
1122 | ||
c0a0d0d3 | 1123 | #ifdef CONFIG_STACKTRACE |
e77405ad | 1124 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 SR |
1125 | unsigned long flags, |
1126 | int skip, int pc) | |
86387f7e | 1127 | { |
e1112b4d | 1128 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1129 | struct ring_buffer_event *event; |
777e208d | 1130 | struct stack_entry *entry; |
86387f7e IM |
1131 | struct stack_trace trace; |
1132 | ||
e77405ad | 1133 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
51a763dd | 1134 | sizeof(*entry), flags, pc); |
3928a8a2 SR |
1135 | if (!event) |
1136 | return; | |
1137 | entry = ring_buffer_event_data(event); | |
777e208d | 1138 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
1139 | |
1140 | trace.nr_entries = 0; | |
1141 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1142 | trace.skip = skip; | |
777e208d | 1143 | trace.entries = entry->caller; |
86387f7e IM |
1144 | |
1145 | save_stack_trace(&trace); | |
e77405ad SR |
1146 | if (!filter_check_discard(call, entry, buffer, event)) |
1147 | ring_buffer_unlock_commit(buffer, event); | |
f0a920d5 IM |
1148 | } |
1149 | ||
e77405ad SR |
1150 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1151 | int skip, int pc) | |
53614991 SR |
1152 | { |
1153 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1154 | return; | |
1155 | ||
e77405ad | 1156 | __ftrace_trace_stack(buffer, flags, skip, pc); |
53614991 SR |
1157 | } |
1158 | ||
c0a0d0d3 FW |
1159 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1160 | int pc) | |
38697053 | 1161 | { |
e77405ad | 1162 | __ftrace_trace_stack(tr->buffer, flags, skip, pc); |
38697053 SR |
1163 | } |
1164 | ||
e77405ad SR |
1165 | void |
1166 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1167 | { |
e1112b4d | 1168 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1169 | struct ring_buffer_event *event; |
02b67518 TE |
1170 | struct userstack_entry *entry; |
1171 | struct stack_trace trace; | |
02b67518 TE |
1172 | |
1173 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1174 | return; | |
1175 | ||
e77405ad | 1176 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1177 | sizeof(*entry), flags, pc); |
02b67518 TE |
1178 | if (!event) |
1179 | return; | |
1180 | entry = ring_buffer_event_data(event); | |
02b67518 | 1181 | |
48659d31 | 1182 | entry->tgid = current->tgid; |
02b67518 TE |
1183 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1184 | ||
1185 | trace.nr_entries = 0; | |
1186 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1187 | trace.skip = 0; | |
1188 | trace.entries = entry->caller; | |
1189 | ||
1190 | save_stack_trace_user(&trace); | |
e77405ad SR |
1191 | if (!filter_check_discard(call, entry, buffer, event)) |
1192 | ring_buffer_unlock_commit(buffer, event); | |
02b67518 TE |
1193 | } |
1194 | ||
4fd27358 HE |
1195 | #ifdef UNUSED |
1196 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1197 | { |
7be42151 | 1198 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1199 | } |
4fd27358 | 1200 | #endif /* UNUSED */ |
02b67518 | 1201 | |
c0a0d0d3 FW |
1202 | #endif /* CONFIG_STACKTRACE */ |
1203 | ||
38697053 | 1204 | static void |
7be42151 | 1205 | ftrace_trace_special(void *__tr, |
38697053 SR |
1206 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1207 | int pc) | |
a4feb834 | 1208 | { |
60ba7702 | 1209 | struct ftrace_event_call *call = &event_special; |
3928a8a2 | 1210 | struct ring_buffer_event *event; |
a4feb834 | 1211 | struct trace_array *tr = __tr; |
e77405ad | 1212 | struct ring_buffer *buffer = tr->buffer; |
777e208d | 1213 | struct special_entry *entry; |
a4feb834 | 1214 | |
e77405ad | 1215 | event = trace_buffer_lock_reserve(buffer, TRACE_SPECIAL, |
51a763dd | 1216 | sizeof(*entry), 0, pc); |
3928a8a2 SR |
1217 | if (!event) |
1218 | return; | |
1219 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1220 | entry->arg1 = arg1; |
1221 | entry->arg2 = arg2; | |
1222 | entry->arg3 = arg3; | |
60ba7702 SR |
1223 | |
1224 | if (!filter_check_discard(call, entry, buffer, event)) | |
1225 | trace_buffer_unlock_commit(buffer, event, 0, pc); | |
a4feb834 IM |
1226 | } |
1227 | ||
38697053 SR |
1228 | void |
1229 | __trace_special(void *__tr, void *__data, | |
1230 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1231 | { | |
7be42151 | 1232 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1233 | } |
1234 | ||
4902f884 SR |
1235 | void |
1236 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1237 | { | |
1238 | struct trace_array *tr = &global_trace; | |
1239 | struct trace_array_cpu *data; | |
5aa1ba6a | 1240 | unsigned long flags; |
4902f884 | 1241 | int cpu; |
38697053 | 1242 | int pc; |
4902f884 | 1243 | |
c76f0694 | 1244 | if (tracing_disabled) |
4902f884 SR |
1245 | return; |
1246 | ||
38697053 | 1247 | pc = preempt_count(); |
5aa1ba6a | 1248 | local_irq_save(flags); |
4902f884 SR |
1249 | cpu = raw_smp_processor_id(); |
1250 | data = tr->data[cpu]; | |
4902f884 | 1251 | |
5aa1ba6a | 1252 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1253 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1254 | |
5aa1ba6a SR |
1255 | atomic_dec(&data->disabled); |
1256 | local_irq_restore(flags); | |
4902f884 SR |
1257 | } |
1258 | ||
769b0441 | 1259 | /** |
48ead020 | 1260 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1261 | * |
1262 | */ | |
40ce74f1 | 1263 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1264 | { |
80370cb7 SR |
1265 | static raw_spinlock_t trace_buf_lock = |
1266 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
769b0441 FW |
1267 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1268 | ||
e1112b4d | 1269 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1270 | struct ring_buffer_event *event; |
e77405ad | 1271 | struct ring_buffer *buffer; |
769b0441 FW |
1272 | struct trace_array *tr = &global_trace; |
1273 | struct trace_array_cpu *data; | |
48ead020 | 1274 | struct bprint_entry *entry; |
769b0441 | 1275 | unsigned long flags; |
3189cdb3 | 1276 | int disable; |
769b0441 FW |
1277 | int resched; |
1278 | int cpu, len = 0, size, pc; | |
1279 | ||
1280 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1281 | return 0; | |
1282 | ||
1283 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1284 | pause_graph_tracing(); | |
1285 | ||
1286 | pc = preempt_count(); | |
1287 | resched = ftrace_preempt_disable(); | |
1288 | cpu = raw_smp_processor_id(); | |
1289 | data = tr->data[cpu]; | |
1290 | ||
3189cdb3 SR |
1291 | disable = atomic_inc_return(&data->disabled); |
1292 | if (unlikely(disable != 1)) | |
769b0441 FW |
1293 | goto out; |
1294 | ||
80370cb7 SR |
1295 | /* Lockdep uses trace_printk for lock tracing */ |
1296 | local_irq_save(flags); | |
1297 | __raw_spin_lock(&trace_buf_lock); | |
769b0441 FW |
1298 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1299 | ||
1300 | if (len > TRACE_BUF_SIZE || len < 0) | |
1301 | goto out_unlock; | |
1302 | ||
1303 | size = sizeof(*entry) + sizeof(u32) * len; | |
e77405ad SR |
1304 | buffer = tr->buffer; |
1305 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, | |
1306 | flags, pc); | |
769b0441 FW |
1307 | if (!event) |
1308 | goto out_unlock; | |
1309 | entry = ring_buffer_event_data(event); | |
1310 | entry->ip = ip; | |
769b0441 FW |
1311 | entry->fmt = fmt; |
1312 | ||
1313 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
e77405ad SR |
1314 | if (!filter_check_discard(call, entry, buffer, event)) |
1315 | ring_buffer_unlock_commit(buffer, event); | |
769b0441 FW |
1316 | |
1317 | out_unlock: | |
80370cb7 SR |
1318 | __raw_spin_unlock(&trace_buf_lock); |
1319 | local_irq_restore(flags); | |
769b0441 FW |
1320 | |
1321 | out: | |
3189cdb3 | 1322 | atomic_dec_return(&data->disabled); |
769b0441 FW |
1323 | ftrace_preempt_enable(resched); |
1324 | unpause_graph_tracing(); | |
1325 | ||
1326 | return len; | |
1327 | } | |
48ead020 FW |
1328 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1329 | ||
659372d3 SR |
1330 | int trace_array_printk(struct trace_array *tr, |
1331 | unsigned long ip, const char *fmt, ...) | |
1332 | { | |
1333 | int ret; | |
1334 | va_list ap; | |
1335 | ||
1336 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1337 | return 0; | |
1338 | ||
1339 | va_start(ap, fmt); | |
1340 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
1341 | va_end(ap); | |
1342 | return ret; | |
1343 | } | |
1344 | ||
1345 | int trace_array_vprintk(struct trace_array *tr, | |
1346 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 FW |
1347 | { |
1348 | static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; | |
1349 | static char trace_buf[TRACE_BUF_SIZE]; | |
1350 | ||
e1112b4d | 1351 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1352 | struct ring_buffer_event *event; |
e77405ad | 1353 | struct ring_buffer *buffer; |
48ead020 FW |
1354 | struct trace_array_cpu *data; |
1355 | int cpu, len = 0, size, pc; | |
1356 | struct print_entry *entry; | |
1357 | unsigned long irq_flags; | |
3189cdb3 | 1358 | int disable; |
48ead020 FW |
1359 | |
1360 | if (tracing_disabled || tracing_selftest_running) | |
1361 | return 0; | |
1362 | ||
1363 | pc = preempt_count(); | |
1364 | preempt_disable_notrace(); | |
1365 | cpu = raw_smp_processor_id(); | |
1366 | data = tr->data[cpu]; | |
1367 | ||
3189cdb3 SR |
1368 | disable = atomic_inc_return(&data->disabled); |
1369 | if (unlikely(disable != 1)) | |
48ead020 FW |
1370 | goto out; |
1371 | ||
1372 | pause_graph_tracing(); | |
1373 | raw_local_irq_save(irq_flags); | |
1374 | __raw_spin_lock(&trace_buf_lock); | |
1375 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); | |
1376 | ||
1377 | len = min(len, TRACE_BUF_SIZE-1); | |
1378 | trace_buf[len] = 0; | |
1379 | ||
1380 | size = sizeof(*entry) + len + 1; | |
e77405ad SR |
1381 | buffer = tr->buffer; |
1382 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
1383 | irq_flags, pc); | |
48ead020 FW |
1384 | if (!event) |
1385 | goto out_unlock; | |
1386 | entry = ring_buffer_event_data(event); | |
1387 | entry->ip = ip; | |
48ead020 FW |
1388 | |
1389 | memcpy(&entry->buf, trace_buf, len); | |
1390 | entry->buf[len] = 0; | |
e77405ad SR |
1391 | if (!filter_check_discard(call, entry, buffer, event)) |
1392 | ring_buffer_unlock_commit(buffer, event); | |
48ead020 FW |
1393 | |
1394 | out_unlock: | |
1395 | __raw_spin_unlock(&trace_buf_lock); | |
1396 | raw_local_irq_restore(irq_flags); | |
1397 | unpause_graph_tracing(); | |
1398 | out: | |
3189cdb3 | 1399 | atomic_dec_return(&data->disabled); |
48ead020 FW |
1400 | preempt_enable_notrace(); |
1401 | ||
1402 | return len; | |
1403 | } | |
659372d3 SR |
1404 | |
1405 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) | |
1406 | { | |
1407 | return trace_array_printk(&global_trace, ip, fmt, args); | |
1408 | } | |
769b0441 FW |
1409 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1410 | ||
bc0c38d1 SR |
1411 | enum trace_file_type { |
1412 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1413 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1414 | }; |
1415 | ||
e2ac8ef5 | 1416 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1417 | { |
d769041f SR |
1418 | /* Don't allow ftrace to trace into the ring buffers */ |
1419 | ftrace_disable_cpu(); | |
1420 | ||
5a90f577 | 1421 | iter->idx++; |
d769041f SR |
1422 | if (iter->buffer_iter[iter->cpu]) |
1423 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1424 | ||
1425 | ftrace_enable_cpu(); | |
5a90f577 SR |
1426 | } |
1427 | ||
e309b41d | 1428 | static struct trace_entry * |
3928a8a2 | 1429 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1430 | { |
3928a8a2 SR |
1431 | struct ring_buffer_event *event; |
1432 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1433 | |
d769041f SR |
1434 | /* Don't allow ftrace to trace into the ring buffers */ |
1435 | ftrace_disable_cpu(); | |
1436 | ||
1437 | if (buf_iter) | |
1438 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1439 | else | |
1440 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1441 | ||
1442 | ftrace_enable_cpu(); | |
1443 | ||
3928a8a2 | 1444 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1445 | } |
d769041f | 1446 | |
dd0e545f | 1447 | static struct trace_entry * |
3928a8a2 | 1448 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1449 | { |
3928a8a2 | 1450 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1451 | struct trace_entry *ent, *next = NULL; |
b04cc6b1 | 1452 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1453 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1454 | int next_cpu = -1; |
1455 | int cpu; | |
1456 | ||
b04cc6b1 FW |
1457 | /* |
1458 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1459 | * all cpu and peek directly. | |
1460 | */ | |
1461 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1462 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1463 | return NULL; | |
1464 | ent = peek_next_entry(iter, cpu_file, ent_ts); | |
1465 | if (ent_cpu) | |
1466 | *ent_cpu = cpu_file; | |
1467 | ||
1468 | return ent; | |
1469 | } | |
1470 | ||
ab46428c | 1471 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1472 | |
3928a8a2 SR |
1473 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1474 | continue; | |
dd0e545f | 1475 | |
3928a8a2 | 1476 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1477 | |
cdd31cd2 IM |
1478 | /* |
1479 | * Pick the entry with the smallest timestamp: | |
1480 | */ | |
3928a8a2 | 1481 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1482 | next = ent; |
1483 | next_cpu = cpu; | |
3928a8a2 | 1484 | next_ts = ts; |
bc0c38d1 SR |
1485 | } |
1486 | } | |
1487 | ||
1488 | if (ent_cpu) | |
1489 | *ent_cpu = next_cpu; | |
1490 | ||
3928a8a2 SR |
1491 | if (ent_ts) |
1492 | *ent_ts = next_ts; | |
1493 | ||
bc0c38d1 SR |
1494 | return next; |
1495 | } | |
1496 | ||
dd0e545f | 1497 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1498 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1499 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1500 | { |
3928a8a2 | 1501 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1502 | } |
1503 | ||
1504 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1505 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1506 | { | |
3928a8a2 | 1507 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1508 | |
3928a8a2 | 1509 | if (iter->ent) |
e2ac8ef5 | 1510 | trace_iterator_increment(iter); |
dd0e545f | 1511 | |
3928a8a2 | 1512 | return iter->ent ? iter : NULL; |
b3806b43 | 1513 | } |
bc0c38d1 | 1514 | |
e309b41d | 1515 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1516 | { |
d769041f SR |
1517 | /* Don't allow ftrace to trace into the ring buffers */ |
1518 | ftrace_disable_cpu(); | |
3928a8a2 | 1519 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1520 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1521 | } |
1522 | ||
e309b41d | 1523 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1524 | { |
1525 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1526 | int i = (int)*pos; |
4e3c3333 | 1527 | void *ent; |
bc0c38d1 SR |
1528 | |
1529 | (*pos)++; | |
1530 | ||
1531 | /* can't go backwards */ | |
1532 | if (iter->idx > i) | |
1533 | return NULL; | |
1534 | ||
1535 | if (iter->idx < 0) | |
1536 | ent = find_next_entry_inc(iter); | |
1537 | else | |
1538 | ent = iter; | |
1539 | ||
1540 | while (ent && iter->idx < i) | |
1541 | ent = find_next_entry_inc(iter); | |
1542 | ||
1543 | iter->pos = *pos; | |
1544 | ||
bc0c38d1 SR |
1545 | return ent; |
1546 | } | |
1547 | ||
2f26ebd5 SR |
1548 | static void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
1549 | { | |
1550 | struct trace_array *tr = iter->tr; | |
1551 | struct ring_buffer_event *event; | |
1552 | struct ring_buffer_iter *buf_iter; | |
1553 | unsigned long entries = 0; | |
1554 | u64 ts; | |
1555 | ||
1556 | tr->data[cpu]->skipped_entries = 0; | |
1557 | ||
1558 | if (!iter->buffer_iter[cpu]) | |
1559 | return; | |
1560 | ||
1561 | buf_iter = iter->buffer_iter[cpu]; | |
1562 | ring_buffer_iter_reset(buf_iter); | |
1563 | ||
1564 | /* | |
1565 | * We could have the case with the max latency tracers | |
1566 | * that a reset never took place on a cpu. This is evident | |
1567 | * by the timestamp being before the start of the buffer. | |
1568 | */ | |
1569 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
1570 | if (ts >= iter->tr->time_start) | |
1571 | break; | |
1572 | entries++; | |
1573 | ring_buffer_read(buf_iter, NULL); | |
1574 | } | |
1575 | ||
1576 | tr->data[cpu]->skipped_entries = entries; | |
1577 | } | |
1578 | ||
d7350c3f FW |
1579 | /* |
1580 | * No necessary locking here. The worst thing which can | |
1581 | * happen is loosing events consumed at the same time | |
1582 | * by a trace_pipe reader. | |
1583 | * Other than that, we don't risk to crash the ring buffer | |
1584 | * because it serializes the readers. | |
1585 | * | |
1586 | * The current tracer is copied to avoid a global locking | |
1587 | * all around. | |
1588 | */ | |
bc0c38d1 SR |
1589 | static void *s_start(struct seq_file *m, loff_t *pos) |
1590 | { | |
1591 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1592 | static struct tracer *old_tracer; |
b04cc6b1 | 1593 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1594 | void *p = NULL; |
1595 | loff_t l = 0; | |
3928a8a2 | 1596 | int cpu; |
bc0c38d1 | 1597 | |
d7350c3f | 1598 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1599 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1600 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1601 | old_tracer = current_trace; | |
1602 | *iter->trace = *current_trace; | |
d15f57f2 | 1603 | } |
d7350c3f | 1604 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1605 | |
1606 | atomic_inc(&trace_record_cmdline_disabled); | |
1607 | ||
bc0c38d1 SR |
1608 | if (*pos != iter->pos) { |
1609 | iter->ent = NULL; | |
1610 | iter->cpu = 0; | |
1611 | iter->idx = -1; | |
1612 | ||
d769041f SR |
1613 | ftrace_disable_cpu(); |
1614 | ||
b04cc6b1 FW |
1615 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1616 | for_each_tracing_cpu(cpu) | |
2f26ebd5 | 1617 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 1618 | } else |
2f26ebd5 | 1619 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 1620 | |
d769041f SR |
1621 | ftrace_enable_cpu(); |
1622 | ||
bc0c38d1 SR |
1623 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1624 | ; | |
1625 | ||
1626 | } else { | |
4c11d7ae | 1627 | l = *pos - 1; |
bc0c38d1 SR |
1628 | p = s_next(m, p, &l); |
1629 | } | |
1630 | ||
4f535968 | 1631 | trace_event_read_lock(); |
bc0c38d1 SR |
1632 | return p; |
1633 | } | |
1634 | ||
1635 | static void s_stop(struct seq_file *m, void *p) | |
1636 | { | |
bc0c38d1 | 1637 | atomic_dec(&trace_record_cmdline_disabled); |
4f535968 | 1638 | trace_event_read_unlock(); |
bc0c38d1 SR |
1639 | } |
1640 | ||
e309b41d | 1641 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1642 | { |
a6168353 ME |
1643 | seq_puts(m, "# _------=> CPU# \n"); |
1644 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1645 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1646 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1647 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
637e7e86 SR |
1648 | seq_puts(m, "# |||| /_--=> lock-depth \n"); |
1649 | seq_puts(m, "# |||||/ delay \n"); | |
1650 | seq_puts(m, "# cmd pid |||||| time | caller \n"); | |
1651 | seq_puts(m, "# \\ / |||||| \\ | / \n"); | |
bc0c38d1 SR |
1652 | } |
1653 | ||
e309b41d | 1654 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1655 | { |
a6168353 ME |
1656 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1657 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1658 | } |
1659 | ||
1660 | ||
e309b41d | 1661 | static void |
bc0c38d1 SR |
1662 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1663 | { | |
1664 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1665 | struct trace_array *tr = iter->tr; | |
1666 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1667 | struct tracer *type = current_trace; | |
2f26ebd5 SR |
1668 | unsigned long entries = 0; |
1669 | unsigned long total = 0; | |
1670 | unsigned long count; | |
bc0c38d1 | 1671 | const char *name = "preemption"; |
2f26ebd5 | 1672 | int cpu; |
bc0c38d1 SR |
1673 | |
1674 | if (type) | |
1675 | name = type->name; | |
1676 | ||
2f26ebd5 SR |
1677 | |
1678 | for_each_tracing_cpu(cpu) { | |
1679 | count = ring_buffer_entries_cpu(tr->buffer, cpu); | |
1680 | /* | |
1681 | * If this buffer has skipped entries, then we hold all | |
1682 | * entries for the trace and we need to ignore the | |
1683 | * ones before the time stamp. | |
1684 | */ | |
1685 | if (tr->data[cpu]->skipped_entries) { | |
1686 | count -= tr->data[cpu]->skipped_entries; | |
1687 | /* total is the same as the entries */ | |
1688 | total += count; | |
1689 | } else | |
1690 | total += count + | |
1691 | ring_buffer_overrun_cpu(tr->buffer, cpu); | |
1692 | entries += count; | |
1693 | } | |
bc0c38d1 | 1694 | |
888b55dc | 1695 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1696 | name, UTS_RELEASE); |
888b55dc | 1697 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1698 | "---------------------------------\n"); |
888b55dc | 1699 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1700 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1701 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1702 | entries, |
4c11d7ae | 1703 | total, |
bc0c38d1 SR |
1704 | tr->cpu, |
1705 | #if defined(CONFIG_PREEMPT_NONE) | |
1706 | "server", | |
1707 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1708 | "desktop", | |
b5c21b45 | 1709 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1710 | "preempt", |
1711 | #else | |
1712 | "unknown", | |
1713 | #endif | |
1714 | /* These are reserved for later use */ | |
1715 | 0, 0, 0, 0); | |
1716 | #ifdef CONFIG_SMP | |
1717 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1718 | #else | |
1719 | seq_puts(m, ")\n"); | |
1720 | #endif | |
888b55dc KM |
1721 | seq_puts(m, "# -----------------\n"); |
1722 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1723 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1724 | data->comm, data->pid, data->uid, data->nice, | |
1725 | data->policy, data->rt_priority); | |
888b55dc | 1726 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1727 | |
1728 | if (data->critical_start) { | |
888b55dc | 1729 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1730 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1731 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1732 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1733 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1734 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 1735 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
1736 | } |
1737 | ||
888b55dc | 1738 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1739 | } |
1740 | ||
a309720c SR |
1741 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1742 | { | |
1743 | struct trace_seq *s = &iter->seq; | |
1744 | ||
12ef7d44 SR |
1745 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1746 | return; | |
1747 | ||
1748 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1749 | return; | |
1750 | ||
4462344e | 1751 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1752 | return; |
1753 | ||
2f26ebd5 SR |
1754 | if (iter->tr->data[iter->cpu]->skipped_entries) |
1755 | return; | |
1756 | ||
4462344e | 1757 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1758 | |
1759 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1760 | if (iter->idx > 1) | |
1761 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1762 | iter->cpu); | |
a309720c SR |
1763 | } |
1764 | ||
2c4f035f | 1765 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1766 | { |
214023c3 | 1767 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1768 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1769 | struct trace_entry *entry; |
f633cef0 | 1770 | struct trace_event *event; |
bc0c38d1 | 1771 | |
4e3c3333 | 1772 | entry = iter->ent; |
dd0e545f | 1773 | |
a309720c SR |
1774 | test_cpu_buff_start(iter); |
1775 | ||
c4a8e8be | 1776 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1777 | |
c4a8e8be | 1778 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1779 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1780 | if (!trace_print_lat_context(iter)) | |
1781 | goto partial; | |
1782 | } else { | |
1783 | if (!trace_print_context(iter)) | |
1784 | goto partial; | |
1785 | } | |
c4a8e8be | 1786 | } |
bc0c38d1 | 1787 | |
268ccda0 | 1788 | if (event) |
d9793bd8 ACM |
1789 | return event->trace(iter, sym_flags); |
1790 | ||
1791 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1792 | goto partial; | |
02b67518 | 1793 | |
2c4f035f | 1794 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1795 | partial: |
1796 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1797 | } |
1798 | ||
2c4f035f | 1799 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1800 | { |
1801 | struct trace_seq *s = &iter->seq; | |
1802 | struct trace_entry *entry; | |
f633cef0 | 1803 | struct trace_event *event; |
f9896bf3 IM |
1804 | |
1805 | entry = iter->ent; | |
dd0e545f | 1806 | |
c4a8e8be | 1807 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1808 | if (!trace_seq_printf(s, "%d %d %llu ", |
1809 | entry->pid, iter->cpu, iter->ts)) | |
1810 | goto partial; | |
c4a8e8be | 1811 | } |
f9896bf3 | 1812 | |
f633cef0 | 1813 | event = ftrace_find_event(entry->type); |
268ccda0 | 1814 | if (event) |
d9793bd8 ACM |
1815 | return event->raw(iter, 0); |
1816 | ||
1817 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1818 | goto partial; | |
777e208d | 1819 | |
2c4f035f | 1820 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1821 | partial: |
1822 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1823 | } |
1824 | ||
2c4f035f | 1825 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1826 | { |
1827 | struct trace_seq *s = &iter->seq; | |
1828 | unsigned char newline = '\n'; | |
1829 | struct trace_entry *entry; | |
f633cef0 | 1830 | struct trace_event *event; |
5e3ca0ec IM |
1831 | |
1832 | entry = iter->ent; | |
dd0e545f | 1833 | |
c4a8e8be FW |
1834 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1835 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1836 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1837 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1838 | } | |
5e3ca0ec | 1839 | |
f633cef0 | 1840 | event = ftrace_find_event(entry->type); |
268ccda0 | 1841 | if (event) { |
ae7462b4 | 1842 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1843 | if (ret != TRACE_TYPE_HANDLED) |
1844 | return ret; | |
1845 | } | |
7104f300 | 1846 | |
5e3ca0ec IM |
1847 | SEQ_PUT_FIELD_RET(s, newline); |
1848 | ||
2c4f035f | 1849 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1850 | } |
1851 | ||
2c4f035f | 1852 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1853 | { |
1854 | struct trace_seq *s = &iter->seq; | |
1855 | struct trace_entry *entry; | |
f633cef0 | 1856 | struct trace_event *event; |
cb0f12aa IM |
1857 | |
1858 | entry = iter->ent; | |
dd0e545f | 1859 | |
c4a8e8be FW |
1860 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1861 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1862 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1863 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1864 | } | |
cb0f12aa | 1865 | |
f633cef0 | 1866 | event = ftrace_find_event(entry->type); |
268ccda0 | 1867 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1868 | } |
1869 | ||
bc0c38d1 SR |
1870 | static int trace_empty(struct trace_iterator *iter) |
1871 | { | |
bc0c38d1 SR |
1872 | int cpu; |
1873 | ||
9aba60fe SR |
1874 | /* If we are looking at one CPU buffer, only check that one */ |
1875 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1876 | cpu = iter->cpu_file; | |
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 | } | |
1884 | return 1; | |
1885 | } | |
1886 | ||
ab46428c | 1887 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1888 | if (iter->buffer_iter[cpu]) { |
1889 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1890 | return 0; | |
1891 | } else { | |
1892 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1893 | return 0; | |
1894 | } | |
bc0c38d1 | 1895 | } |
d769041f | 1896 | |
797d3712 | 1897 | return 1; |
bc0c38d1 SR |
1898 | } |
1899 | ||
4f535968 | 1900 | /* Called with trace_event_read_lock() held. */ |
2c4f035f | 1901 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1902 | { |
2c4f035f FW |
1903 | enum print_line_t ret; |
1904 | ||
1905 | if (iter->trace && iter->trace->print_line) { | |
1906 | ret = iter->trace->print_line(iter); | |
1907 | if (ret != TRACE_TYPE_UNHANDLED) | |
1908 | return ret; | |
1909 | } | |
72829bc3 | 1910 | |
48ead020 FW |
1911 | if (iter->ent->type == TRACE_BPRINT && |
1912 | trace_flags & TRACE_ITER_PRINTK && | |
1913 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1914 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 1915 | |
66896a85 FW |
1916 | if (iter->ent->type == TRACE_PRINT && |
1917 | trace_flags & TRACE_ITER_PRINTK && | |
1918 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1919 | return trace_print_printk_msg_only(iter); |
66896a85 | 1920 | |
cb0f12aa IM |
1921 | if (trace_flags & TRACE_ITER_BIN) |
1922 | return print_bin_fmt(iter); | |
1923 | ||
5e3ca0ec IM |
1924 | if (trace_flags & TRACE_ITER_HEX) |
1925 | return print_hex_fmt(iter); | |
1926 | ||
f9896bf3 IM |
1927 | if (trace_flags & TRACE_ITER_RAW) |
1928 | return print_raw_fmt(iter); | |
1929 | ||
f9896bf3 IM |
1930 | return print_trace_fmt(iter); |
1931 | } | |
1932 | ||
bc0c38d1 SR |
1933 | static int s_show(struct seq_file *m, void *v) |
1934 | { | |
1935 | struct trace_iterator *iter = v; | |
1936 | ||
1937 | if (iter->ent == NULL) { | |
1938 | if (iter->tr) { | |
1939 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1940 | seq_puts(m, "#\n"); | |
1941 | } | |
8bba1bf5 MM |
1942 | if (iter->trace && iter->trace->print_header) |
1943 | iter->trace->print_header(m); | |
1944 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
1945 | /* print nothing if the buffers are empty */ |
1946 | if (trace_empty(iter)) | |
1947 | return 0; | |
1948 | print_trace_header(m, iter); | |
1949 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1950 | print_lat_help_header(m); | |
1951 | } else { | |
1952 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1953 | print_func_help_header(m); | |
1954 | } | |
1955 | } else { | |
f9896bf3 | 1956 | print_trace_line(iter); |
214023c3 | 1957 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1958 | } |
1959 | ||
1960 | return 0; | |
1961 | } | |
1962 | ||
1963 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1964 | .start = s_start, |
1965 | .next = s_next, | |
1966 | .stop = s_stop, | |
1967 | .show = s_show, | |
bc0c38d1 SR |
1968 | }; |
1969 | ||
e309b41d | 1970 | static struct trace_iterator * |
85a2f9b4 | 1971 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 1972 | { |
b04cc6b1 | 1973 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 1974 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 1975 | struct trace_iterator *iter; |
3928a8a2 | 1976 | struct seq_file *m; |
85a2f9b4 | 1977 | int cpu, ret; |
bc0c38d1 | 1978 | |
85a2f9b4 SR |
1979 | if (tracing_disabled) |
1980 | return ERR_PTR(-ENODEV); | |
60a11774 | 1981 | |
bc0c38d1 | 1982 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
1983 | if (!iter) |
1984 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 1985 | |
d7350c3f FW |
1986 | /* |
1987 | * We make a copy of the current tracer to avoid concurrent | |
1988 | * changes on it while we are reading. | |
1989 | */ | |
bc0c38d1 | 1990 | mutex_lock(&trace_types_lock); |
d7350c3f | 1991 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 1992 | if (!iter->trace) |
d7350c3f | 1993 | goto fail; |
85a2f9b4 | 1994 | |
d7350c3f FW |
1995 | if (current_trace) |
1996 | *iter->trace = *current_trace; | |
1997 | ||
b0dfa978 FW |
1998 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) |
1999 | goto fail; | |
2000 | ||
2001 | cpumask_clear(iter->started); | |
2002 | ||
bc0c38d1 SR |
2003 | if (current_trace && current_trace->print_max) |
2004 | iter->tr = &max_tr; | |
2005 | else | |
b04cc6b1 | 2006 | iter->tr = &global_trace; |
bc0c38d1 | 2007 | iter->pos = -1; |
d7350c3f | 2008 | mutex_init(&iter->mutex); |
b04cc6b1 | 2009 | iter->cpu_file = cpu_file; |
bc0c38d1 | 2010 | |
8bba1bf5 MM |
2011 | /* Notify the tracer early; before we stop tracing. */ |
2012 | if (iter->trace && iter->trace->open) | |
a93751ca | 2013 | iter->trace->open(iter); |
8bba1bf5 | 2014 | |
12ef7d44 SR |
2015 | /* Annotate start of buffers if we had overruns */ |
2016 | if (ring_buffer_overruns(iter->tr->buffer)) | |
2017 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
2018 | ||
2f26ebd5 SR |
2019 | /* stop the trace while dumping */ |
2020 | tracing_stop(); | |
2021 | ||
b04cc6b1 FW |
2022 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
2023 | for_each_tracing_cpu(cpu) { | |
12ef7d44 | 2024 | |
b04cc6b1 FW |
2025 | iter->buffer_iter[cpu] = |
2026 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
2f26ebd5 | 2027 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2028 | } |
2029 | } else { | |
2030 | cpu = iter->cpu_file; | |
3928a8a2 | 2031 | iter->buffer_iter[cpu] = |
b04cc6b1 | 2032 | ring_buffer_read_start(iter->tr->buffer, cpu); |
2f26ebd5 | 2033 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2034 | } |
2035 | ||
85a2f9b4 SR |
2036 | ret = seq_open(file, &tracer_seq_ops); |
2037 | if (ret < 0) { | |
2038 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 2039 | goto fail_buffer; |
85a2f9b4 | 2040 | } |
bc0c38d1 | 2041 | |
3928a8a2 SR |
2042 | m = file->private_data; |
2043 | m->private = iter; | |
bc0c38d1 | 2044 | |
bc0c38d1 SR |
2045 | mutex_unlock(&trace_types_lock); |
2046 | ||
bc0c38d1 | 2047 | return iter; |
3928a8a2 SR |
2048 | |
2049 | fail_buffer: | |
2050 | for_each_tracing_cpu(cpu) { | |
2051 | if (iter->buffer_iter[cpu]) | |
2052 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2053 | } | |
b0dfa978 | 2054 | free_cpumask_var(iter->started); |
2f26ebd5 | 2055 | tracing_start(); |
d7350c3f | 2056 | fail: |
3928a8a2 | 2057 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2058 | kfree(iter->trace); |
0bb943c7 | 2059 | kfree(iter); |
3928a8a2 | 2060 | |
85a2f9b4 | 2061 | return fail_ret; |
bc0c38d1 SR |
2062 | } |
2063 | ||
2064 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2065 | { | |
60a11774 SR |
2066 | if (tracing_disabled) |
2067 | return -ENODEV; | |
2068 | ||
bc0c38d1 SR |
2069 | filp->private_data = inode->i_private; |
2070 | return 0; | |
2071 | } | |
2072 | ||
4fd27358 | 2073 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
2074 | { |
2075 | struct seq_file *m = (struct seq_file *)file->private_data; | |
4acd4d00 | 2076 | struct trace_iterator *iter; |
3928a8a2 | 2077 | int cpu; |
bc0c38d1 | 2078 | |
4acd4d00 SR |
2079 | if (!(file->f_mode & FMODE_READ)) |
2080 | return 0; | |
2081 | ||
2082 | iter = m->private; | |
2083 | ||
bc0c38d1 | 2084 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
2085 | for_each_tracing_cpu(cpu) { |
2086 | if (iter->buffer_iter[cpu]) | |
2087 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2088 | } | |
2089 | ||
bc0c38d1 SR |
2090 | if (iter->trace && iter->trace->close) |
2091 | iter->trace->close(iter); | |
2092 | ||
2093 | /* reenable tracing if it was previously enabled */ | |
9036990d | 2094 | tracing_start(); |
bc0c38d1 SR |
2095 | mutex_unlock(&trace_types_lock); |
2096 | ||
2097 | seq_release(inode, file); | |
d7350c3f | 2098 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2099 | free_cpumask_var(iter->started); |
d7350c3f | 2100 | kfree(iter->trace); |
bc0c38d1 SR |
2101 | kfree(iter); |
2102 | return 0; | |
2103 | } | |
2104 | ||
2105 | static int tracing_open(struct inode *inode, struct file *file) | |
2106 | { | |
85a2f9b4 SR |
2107 | struct trace_iterator *iter; |
2108 | int ret = 0; | |
bc0c38d1 | 2109 | |
4acd4d00 SR |
2110 | /* If this file was open for write, then erase contents */ |
2111 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2112 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 2113 | long cpu = (long) inode->i_private; |
bc0c38d1 | 2114 | |
4acd4d00 SR |
2115 | if (cpu == TRACE_PIPE_ALL_CPU) |
2116 | tracing_reset_online_cpus(&global_trace); | |
2117 | else | |
2118 | tracing_reset(&global_trace, cpu); | |
2119 | } | |
bc0c38d1 | 2120 | |
4acd4d00 SR |
2121 | if (file->f_mode & FMODE_READ) { |
2122 | iter = __tracing_open(inode, file); | |
2123 | if (IS_ERR(iter)) | |
2124 | ret = PTR_ERR(iter); | |
2125 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2126 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2127 | } | |
bc0c38d1 SR |
2128 | return ret; |
2129 | } | |
2130 | ||
e309b41d | 2131 | static void * |
bc0c38d1 SR |
2132 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2133 | { | |
f129e965 | 2134 | struct tracer *t = v; |
bc0c38d1 SR |
2135 | |
2136 | (*pos)++; | |
2137 | ||
2138 | if (t) | |
2139 | t = t->next; | |
2140 | ||
bc0c38d1 SR |
2141 | return t; |
2142 | } | |
2143 | ||
2144 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2145 | { | |
f129e965 | 2146 | struct tracer *t; |
bc0c38d1 SR |
2147 | loff_t l = 0; |
2148 | ||
2149 | mutex_lock(&trace_types_lock); | |
f129e965 | 2150 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2151 | ; |
2152 | ||
2153 | return t; | |
2154 | } | |
2155 | ||
2156 | static void t_stop(struct seq_file *m, void *p) | |
2157 | { | |
2158 | mutex_unlock(&trace_types_lock); | |
2159 | } | |
2160 | ||
2161 | static int t_show(struct seq_file *m, void *v) | |
2162 | { | |
2163 | struct tracer *t = v; | |
2164 | ||
2165 | if (!t) | |
2166 | return 0; | |
2167 | ||
2168 | seq_printf(m, "%s", t->name); | |
2169 | if (t->next) | |
2170 | seq_putc(m, ' '); | |
2171 | else | |
2172 | seq_putc(m, '\n'); | |
2173 | ||
2174 | return 0; | |
2175 | } | |
2176 | ||
2177 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
2178 | .start = t_start, |
2179 | .next = t_next, | |
2180 | .stop = t_stop, | |
2181 | .show = t_show, | |
bc0c38d1 SR |
2182 | }; |
2183 | ||
2184 | static int show_traces_open(struct inode *inode, struct file *file) | |
2185 | { | |
60a11774 SR |
2186 | if (tracing_disabled) |
2187 | return -ENODEV; | |
2188 | ||
f129e965 | 2189 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2190 | } |
2191 | ||
4acd4d00 SR |
2192 | static ssize_t |
2193 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2194 | size_t count, loff_t *ppos) | |
2195 | { | |
2196 | return count; | |
2197 | } | |
2198 | ||
5e2336a0 | 2199 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2200 | .open = tracing_open, |
2201 | .read = seq_read, | |
4acd4d00 | 2202 | .write = tracing_write_stub, |
4bf39a94 IM |
2203 | .llseek = seq_lseek, |
2204 | .release = tracing_release, | |
bc0c38d1 SR |
2205 | }; |
2206 | ||
5e2336a0 | 2207 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2208 | .open = show_traces_open, |
2209 | .read = seq_read, | |
2210 | .release = seq_release, | |
2211 | }; | |
2212 | ||
36dfe925 IM |
2213 | /* |
2214 | * Only trace on a CPU if the bitmask is set: | |
2215 | */ | |
9e01c1b7 | 2216 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2217 | |
2218 | /* | |
2219 | * The tracer itself will not take this lock, but still we want | |
2220 | * to provide a consistent cpumask to user-space: | |
2221 | */ | |
2222 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2223 | ||
2224 | /* | |
2225 | * Temporary storage for the character representation of the | |
2226 | * CPU bitmask (and one more byte for the newline): | |
2227 | */ | |
2228 | static char mask_str[NR_CPUS + 1]; | |
2229 | ||
c7078de1 IM |
2230 | static ssize_t |
2231 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2232 | size_t count, loff_t *ppos) | |
2233 | { | |
36dfe925 | 2234 | int len; |
c7078de1 IM |
2235 | |
2236 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2237 | |
9e01c1b7 | 2238 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2239 | if (count - len < 2) { |
2240 | count = -EINVAL; | |
2241 | goto out_err; | |
2242 | } | |
2243 | len += sprintf(mask_str + len, "\n"); | |
2244 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2245 | ||
2246 | out_err: | |
c7078de1 IM |
2247 | mutex_unlock(&tracing_cpumask_update_lock); |
2248 | ||
2249 | return count; | |
2250 | } | |
2251 | ||
2252 | static ssize_t | |
2253 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2254 | size_t count, loff_t *ppos) | |
2255 | { | |
36dfe925 | 2256 | int err, cpu; |
9e01c1b7 RR |
2257 | cpumask_var_t tracing_cpumask_new; |
2258 | ||
2259 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2260 | return -ENOMEM; | |
c7078de1 | 2261 | |
9e01c1b7 | 2262 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2263 | if (err) |
36dfe925 IM |
2264 | goto err_unlock; |
2265 | ||
215368e8 LZ |
2266 | mutex_lock(&tracing_cpumask_update_lock); |
2267 | ||
a5e25883 | 2268 | local_irq_disable(); |
92205c23 | 2269 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 2270 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2271 | /* |
2272 | * Increase/decrease the disabled counter if we are | |
2273 | * about to flip a bit in the cpumask: | |
2274 | */ | |
9e01c1b7 RR |
2275 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2276 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2277 | atomic_inc(&global_trace.data[cpu]->disabled); |
2278 | } | |
9e01c1b7 RR |
2279 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2280 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2281 | atomic_dec(&global_trace.data[cpu]->disabled); |
2282 | } | |
2283 | } | |
92205c23 | 2284 | __raw_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2285 | local_irq_enable(); |
36dfe925 | 2286 | |
9e01c1b7 | 2287 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2288 | |
2289 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2290 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2291 | |
2292 | return count; | |
36dfe925 IM |
2293 | |
2294 | err_unlock: | |
215368e8 | 2295 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2296 | |
2297 | return err; | |
c7078de1 IM |
2298 | } |
2299 | ||
5e2336a0 | 2300 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2301 | .open = tracing_open_generic, |
2302 | .read = tracing_cpumask_read, | |
2303 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2304 | }; |
2305 | ||
2306 | static ssize_t | |
ee6bce52 | 2307 | tracing_trace_options_read(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
2308 | size_t cnt, loff_t *ppos) |
2309 | { | |
d8e83d26 SR |
2310 | struct tracer_opt *trace_opts; |
2311 | u32 tracer_flags; | |
2312 | int len = 0; | |
bc0c38d1 SR |
2313 | char *buf; |
2314 | int r = 0; | |
d8e83d26 | 2315 | int i; |
adf9f195 | 2316 | |
bc0c38d1 | 2317 | |
c3706f00 | 2318 | /* calculate max size */ |
bc0c38d1 SR |
2319 | for (i = 0; trace_options[i]; i++) { |
2320 | len += strlen(trace_options[i]); | |
5c6a3ae1 | 2321 | len += 3; /* "no" and newline */ |
bc0c38d1 SR |
2322 | } |
2323 | ||
d8e83d26 SR |
2324 | mutex_lock(&trace_types_lock); |
2325 | tracer_flags = current_trace->flags->val; | |
2326 | trace_opts = current_trace->flags->opts; | |
2327 | ||
adf9f195 FW |
2328 | /* |
2329 | * Increase the size with names of options specific | |
2330 | * of the current tracer. | |
2331 | */ | |
2332 | for (i = 0; trace_opts[i].name; i++) { | |
2333 | len += strlen(trace_opts[i].name); | |
5c6a3ae1 | 2334 | len += 3; /* "no" and newline */ |
adf9f195 FW |
2335 | } |
2336 | ||
ff4e9da2 XG |
2337 | /* +1 for \0 */ |
2338 | buf = kmalloc(len + 1, GFP_KERNEL); | |
d8e83d26 SR |
2339 | if (!buf) { |
2340 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 2341 | return -ENOMEM; |
d8e83d26 | 2342 | } |
bc0c38d1 SR |
2343 | |
2344 | for (i = 0; trace_options[i]; i++) { | |
2345 | if (trace_flags & (1 << i)) | |
5c6a3ae1 | 2346 | r += sprintf(buf + r, "%s\n", trace_options[i]); |
bc0c38d1 | 2347 | else |
5c6a3ae1 | 2348 | r += sprintf(buf + r, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2349 | } |
2350 | ||
adf9f195 FW |
2351 | for (i = 0; trace_opts[i].name; i++) { |
2352 | if (tracer_flags & trace_opts[i].bit) | |
5c6a3ae1 | 2353 | r += sprintf(buf + r, "%s\n", |
adf9f195 FW |
2354 | trace_opts[i].name); |
2355 | else | |
5c6a3ae1 | 2356 | r += sprintf(buf + r, "no%s\n", |
adf9f195 FW |
2357 | trace_opts[i].name); |
2358 | } | |
d8e83d26 | 2359 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2360 | |
ff4e9da2 | 2361 | WARN_ON(r >= len + 1); |
bc0c38d1 | 2362 | |
36dfe925 | 2363 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2364 | |
2365 | kfree(buf); | |
bc0c38d1 SR |
2366 | return r; |
2367 | } | |
2368 | ||
adf9f195 FW |
2369 | /* Try to assign a tracer specific option */ |
2370 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2371 | { | |
7770841e | 2372 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 FW |
2373 | struct tracer_opt *opts = NULL; |
2374 | int ret = 0, i = 0; | |
2375 | int len; | |
2376 | ||
7770841e Z |
2377 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2378 | opts = &tracer_flags->opts[i]; | |
adf9f195 FW |
2379 | len = strlen(opts->name); |
2380 | ||
2381 | if (strncmp(cmp, opts->name, len) == 0) { | |
7770841e | 2382 | ret = trace->set_flag(tracer_flags->val, |
adf9f195 FW |
2383 | opts->bit, !neg); |
2384 | break; | |
2385 | } | |
2386 | } | |
2387 | /* Not found */ | |
7770841e | 2388 | if (!tracer_flags->opts[i].name) |
adf9f195 FW |
2389 | return -EINVAL; |
2390 | ||
2391 | /* Refused to handle */ | |
2392 | if (ret) | |
2393 | return ret; | |
2394 | ||
2395 | if (neg) | |
7770841e | 2396 | tracer_flags->val &= ~opts->bit; |
adf9f195 | 2397 | else |
7770841e | 2398 | tracer_flags->val |= opts->bit; |
adf9f195 FW |
2399 | |
2400 | return 0; | |
2401 | } | |
2402 | ||
af4617bd SR |
2403 | static void set_tracer_flags(unsigned int mask, int enabled) |
2404 | { | |
2405 | /* do nothing if flag is already set */ | |
2406 | if (!!(trace_flags & mask) == !!enabled) | |
2407 | return; | |
2408 | ||
2409 | if (enabled) | |
2410 | trace_flags |= mask; | |
2411 | else | |
2412 | trace_flags &= ~mask; | |
af4617bd SR |
2413 | } |
2414 | ||
bc0c38d1 | 2415 | static ssize_t |
ee6bce52 | 2416 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2417 | size_t cnt, loff_t *ppos) |
2418 | { | |
2419 | char buf[64]; | |
2420 | char *cmp = buf; | |
2421 | int neg = 0; | |
adf9f195 | 2422 | int ret; |
bc0c38d1 SR |
2423 | int i; |
2424 | ||
cffae437 SR |
2425 | if (cnt >= sizeof(buf)) |
2426 | return -EINVAL; | |
bc0c38d1 SR |
2427 | |
2428 | if (copy_from_user(&buf, ubuf, cnt)) | |
2429 | return -EFAULT; | |
2430 | ||
2431 | buf[cnt] = 0; | |
2432 | ||
2433 | if (strncmp(buf, "no", 2) == 0) { | |
2434 | neg = 1; | |
2435 | cmp += 2; | |
2436 | } | |
2437 | ||
2438 | for (i = 0; trace_options[i]; i++) { | |
2439 | int len = strlen(trace_options[i]); | |
2440 | ||
2441 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
af4617bd | 2442 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2443 | break; |
2444 | } | |
2445 | } | |
adf9f195 FW |
2446 | |
2447 | /* If no option could be set, test the specific tracer options */ | |
2448 | if (!trace_options[i]) { | |
d8e83d26 | 2449 | mutex_lock(&trace_types_lock); |
adf9f195 | 2450 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2451 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2452 | if (ret) |
2453 | return ret; | |
2454 | } | |
bc0c38d1 SR |
2455 | |
2456 | filp->f_pos += cnt; | |
2457 | ||
2458 | return cnt; | |
2459 | } | |
2460 | ||
5e2336a0 | 2461 | static const struct file_operations tracing_iter_fops = { |
c7078de1 | 2462 | .open = tracing_open_generic, |
ee6bce52 SR |
2463 | .read = tracing_trace_options_read, |
2464 | .write = tracing_trace_options_write, | |
bc0c38d1 SR |
2465 | }; |
2466 | ||
7bd2f24c IM |
2467 | static const char readme_msg[] = |
2468 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2469 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2470 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
bc2b6871 | 2471 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
156f5a78 | 2472 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2473 | "nop\n" |
156f5a78 GL |
2474 | "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" |
2475 | "# cat /sys/kernel/debug/tracing/current_tracer\n" | |
7bd2f24c | 2476 | "sched_switch\n" |
156f5a78 | 2477 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2478 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 GL |
2479 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
2480 | "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
2481 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" | |
2482 | "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
7bd2f24c IM |
2483 | ; |
2484 | ||
2485 | static ssize_t | |
2486 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2487 | size_t cnt, loff_t *ppos) | |
2488 | { | |
2489 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2490 | readme_msg, strlen(readme_msg)); | |
2491 | } | |
2492 | ||
5e2336a0 | 2493 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2494 | .open = tracing_open_generic, |
2495 | .read = tracing_readme_read, | |
7bd2f24c IM |
2496 | }; |
2497 | ||
69abe6a5 AP |
2498 | static ssize_t |
2499 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2500 | size_t cnt, loff_t *ppos) | |
2501 | { | |
2502 | char *buf_comm; | |
2503 | char *file_buf; | |
2504 | char *buf; | |
2505 | int len = 0; | |
2506 | int pid; | |
2507 | int i; | |
2508 | ||
2509 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2510 | if (!file_buf) | |
2511 | return -ENOMEM; | |
2512 | ||
2513 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2514 | if (!buf_comm) { | |
2515 | kfree(file_buf); | |
2516 | return -ENOMEM; | |
2517 | } | |
2518 | ||
2519 | buf = file_buf; | |
2520 | ||
2521 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2522 | int r; | |
2523 | ||
2524 | pid = map_cmdline_to_pid[i]; | |
2525 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2526 | continue; | |
2527 | ||
2528 | trace_find_cmdline(pid, buf_comm); | |
2529 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2530 | buf += r; | |
2531 | len += r; | |
2532 | } | |
2533 | ||
2534 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2535 | file_buf, len); | |
2536 | ||
2537 | kfree(file_buf); | |
2538 | kfree(buf_comm); | |
2539 | ||
2540 | return len; | |
2541 | } | |
2542 | ||
2543 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2544 | .open = tracing_open_generic, | |
2545 | .read = tracing_saved_cmdlines_read, | |
2546 | }; | |
2547 | ||
bc0c38d1 SR |
2548 | static ssize_t |
2549 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2550 | size_t cnt, loff_t *ppos) | |
2551 | { | |
bc0c38d1 SR |
2552 | char buf[64]; |
2553 | int r; | |
2554 | ||
9036990d | 2555 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2556 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2557 | } |
2558 | ||
2559 | static ssize_t | |
2560 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2561 | size_t cnt, loff_t *ppos) | |
2562 | { | |
2563 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2564 | char buf[64]; |
5e39841c | 2565 | unsigned long val; |
c6caeeb1 | 2566 | int ret; |
bc0c38d1 | 2567 | |
cffae437 SR |
2568 | if (cnt >= sizeof(buf)) |
2569 | return -EINVAL; | |
bc0c38d1 SR |
2570 | |
2571 | if (copy_from_user(&buf, ubuf, cnt)) | |
2572 | return -EFAULT; | |
2573 | ||
2574 | buf[cnt] = 0; | |
2575 | ||
c6caeeb1 SR |
2576 | ret = strict_strtoul(buf, 10, &val); |
2577 | if (ret < 0) | |
2578 | return ret; | |
bc0c38d1 SR |
2579 | |
2580 | val = !!val; | |
2581 | ||
2582 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2583 | if (tracer_enabled ^ val) { |
2584 | if (val) { | |
bc0c38d1 | 2585 | tracer_enabled = 1; |
9036990d SR |
2586 | if (current_trace->start) |
2587 | current_trace->start(tr); | |
2588 | tracing_start(); | |
2589 | } else { | |
bc0c38d1 | 2590 | tracer_enabled = 0; |
9036990d SR |
2591 | tracing_stop(); |
2592 | if (current_trace->stop) | |
2593 | current_trace->stop(tr); | |
2594 | } | |
bc0c38d1 SR |
2595 | } |
2596 | mutex_unlock(&trace_types_lock); | |
2597 | ||
2598 | filp->f_pos += cnt; | |
2599 | ||
2600 | return cnt; | |
2601 | } | |
2602 | ||
2603 | static ssize_t | |
2604 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2605 | size_t cnt, loff_t *ppos) | |
2606 | { | |
2607 | char buf[max_tracer_type_len+2]; | |
2608 | int r; | |
2609 | ||
2610 | mutex_lock(&trace_types_lock); | |
2611 | if (current_trace) | |
2612 | r = sprintf(buf, "%s\n", current_trace->name); | |
2613 | else | |
2614 | r = sprintf(buf, "\n"); | |
2615 | mutex_unlock(&trace_types_lock); | |
2616 | ||
4bf39a94 | 2617 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2618 | } |
2619 | ||
b6f11df2 ACM |
2620 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2621 | { | |
2622 | tracing_reset_online_cpus(tr); | |
2623 | return t->init(tr); | |
2624 | } | |
2625 | ||
73c5162a SR |
2626 | static int tracing_resize_ring_buffer(unsigned long size) |
2627 | { | |
2628 | int ret; | |
2629 | ||
2630 | /* | |
2631 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2632 | * we use the size that was given, and we can forget about |
2633 | * expanding it later. | |
73c5162a SR |
2634 | */ |
2635 | ring_buffer_expanded = 1; | |
2636 | ||
2637 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2638 | if (ret < 0) | |
2639 | return ret; | |
2640 | ||
2641 | ret = ring_buffer_resize(max_tr.buffer, size); | |
2642 | if (ret < 0) { | |
2643 | int r; | |
2644 | ||
2645 | r = ring_buffer_resize(global_trace.buffer, | |
2646 | global_trace.entries); | |
2647 | if (r < 0) { | |
a123c52b SR |
2648 | /* |
2649 | * AARGH! We are left with different | |
2650 | * size max buffer!!!! | |
2651 | * The max buffer is our "snapshot" buffer. | |
2652 | * When a tracer needs a snapshot (one of the | |
2653 | * latency tracers), it swaps the max buffer | |
2654 | * with the saved snap shot. We succeeded to | |
2655 | * update the size of the main buffer, but failed to | |
2656 | * update the size of the max buffer. But when we tried | |
2657 | * to reset the main buffer to the original size, we | |
2658 | * failed there too. This is very unlikely to | |
2659 | * happen, but if it does, warn and kill all | |
2660 | * tracing. | |
2661 | */ | |
73c5162a SR |
2662 | WARN_ON(1); |
2663 | tracing_disabled = 1; | |
2664 | } | |
2665 | return ret; | |
2666 | } | |
2667 | ||
2668 | global_trace.entries = size; | |
2669 | ||
2670 | return ret; | |
2671 | } | |
2672 | ||
1852fcce SR |
2673 | /** |
2674 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2675 | * | |
2676 | * To save on memory when the tracing is never used on a system with it | |
2677 | * configured in. The ring buffers are set to a minimum size. But once | |
2678 | * a user starts to use the tracing facility, then they need to grow | |
2679 | * to their default size. | |
2680 | * | |
2681 | * This function is to be called when a tracer is about to be used. | |
2682 | */ | |
2683 | int tracing_update_buffers(void) | |
2684 | { | |
2685 | int ret = 0; | |
2686 | ||
1027fcb2 | 2687 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2688 | if (!ring_buffer_expanded) |
2689 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2690 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2691 | |
2692 | return ret; | |
2693 | } | |
2694 | ||
577b785f SR |
2695 | struct trace_option_dentry; |
2696 | ||
2697 | static struct trace_option_dentry * | |
2698 | create_trace_option_files(struct tracer *tracer); | |
2699 | ||
2700 | static void | |
2701 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2702 | ||
b2821ae6 | 2703 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2704 | { |
577b785f | 2705 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2706 | struct trace_array *tr = &global_trace; |
2707 | struct tracer *t; | |
d9e54076 | 2708 | int ret = 0; |
bc0c38d1 | 2709 | |
1027fcb2 SR |
2710 | mutex_lock(&trace_types_lock); |
2711 | ||
73c5162a SR |
2712 | if (!ring_buffer_expanded) { |
2713 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2714 | if (ret < 0) | |
59f586db | 2715 | goto out; |
73c5162a SR |
2716 | ret = 0; |
2717 | } | |
2718 | ||
bc0c38d1 SR |
2719 | for (t = trace_types; t; t = t->next) { |
2720 | if (strcmp(t->name, buf) == 0) | |
2721 | break; | |
2722 | } | |
c2931e05 FW |
2723 | if (!t) { |
2724 | ret = -EINVAL; | |
2725 | goto out; | |
2726 | } | |
2727 | if (t == current_trace) | |
bc0c38d1 SR |
2728 | goto out; |
2729 | ||
9f029e83 | 2730 | trace_branch_disable(); |
bc0c38d1 SR |
2731 | if (current_trace && current_trace->reset) |
2732 | current_trace->reset(tr); | |
2733 | ||
577b785f SR |
2734 | destroy_trace_option_files(topts); |
2735 | ||
bc0c38d1 | 2736 | current_trace = t; |
577b785f SR |
2737 | |
2738 | topts = create_trace_option_files(current_trace); | |
2739 | ||
1c80025a | 2740 | if (t->init) { |
b6f11df2 | 2741 | ret = tracer_init(t, tr); |
1c80025a FW |
2742 | if (ret) |
2743 | goto out; | |
2744 | } | |
bc0c38d1 | 2745 | |
9f029e83 | 2746 | trace_branch_enable(tr); |
bc0c38d1 SR |
2747 | out: |
2748 | mutex_unlock(&trace_types_lock); | |
2749 | ||
d9e54076 PZ |
2750 | return ret; |
2751 | } | |
2752 | ||
2753 | static ssize_t | |
2754 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2755 | size_t cnt, loff_t *ppos) | |
2756 | { | |
2757 | char buf[max_tracer_type_len+1]; | |
2758 | int i; | |
2759 | size_t ret; | |
e6e7a65a FW |
2760 | int err; |
2761 | ||
2762 | ret = cnt; | |
d9e54076 PZ |
2763 | |
2764 | if (cnt > max_tracer_type_len) | |
2765 | cnt = max_tracer_type_len; | |
2766 | ||
2767 | if (copy_from_user(&buf, ubuf, cnt)) | |
2768 | return -EFAULT; | |
2769 | ||
2770 | buf[cnt] = 0; | |
2771 | ||
2772 | /* strip ending whitespace. */ | |
2773 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2774 | buf[i] = 0; | |
2775 | ||
e6e7a65a FW |
2776 | err = tracing_set_tracer(buf); |
2777 | if (err) | |
2778 | return err; | |
d9e54076 | 2779 | |
e6e7a65a | 2780 | filp->f_pos += ret; |
bc0c38d1 | 2781 | |
c2931e05 | 2782 | return ret; |
bc0c38d1 SR |
2783 | } |
2784 | ||
2785 | static ssize_t | |
2786 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2787 | size_t cnt, loff_t *ppos) | |
2788 | { | |
2789 | unsigned long *ptr = filp->private_data; | |
2790 | char buf[64]; | |
2791 | int r; | |
2792 | ||
cffae437 | 2793 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2794 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2795 | if (r > sizeof(buf)) |
2796 | r = sizeof(buf); | |
4bf39a94 | 2797 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2798 | } |
2799 | ||
2800 | static ssize_t | |
2801 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2802 | size_t cnt, loff_t *ppos) | |
2803 | { | |
5e39841c | 2804 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2805 | char buf[64]; |
5e39841c | 2806 | unsigned long val; |
c6caeeb1 | 2807 | int ret; |
bc0c38d1 | 2808 | |
cffae437 SR |
2809 | if (cnt >= sizeof(buf)) |
2810 | return -EINVAL; | |
bc0c38d1 SR |
2811 | |
2812 | if (copy_from_user(&buf, ubuf, cnt)) | |
2813 | return -EFAULT; | |
2814 | ||
2815 | buf[cnt] = 0; | |
2816 | ||
c6caeeb1 SR |
2817 | ret = strict_strtoul(buf, 10, &val); |
2818 | if (ret < 0) | |
2819 | return ret; | |
bc0c38d1 SR |
2820 | |
2821 | *ptr = val * 1000; | |
2822 | ||
2823 | return cnt; | |
2824 | } | |
2825 | ||
b3806b43 SR |
2826 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2827 | { | |
b04cc6b1 | 2828 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2829 | struct trace_iterator *iter; |
b04cc6b1 | 2830 | int ret = 0; |
b3806b43 SR |
2831 | |
2832 | if (tracing_disabled) | |
2833 | return -ENODEV; | |
2834 | ||
b04cc6b1 FW |
2835 | mutex_lock(&trace_types_lock); |
2836 | ||
2837 | /* We only allow one reader per cpu */ | |
2838 | if (cpu_file == TRACE_PIPE_ALL_CPU) { | |
2839 | if (!cpumask_empty(tracing_reader_cpumask)) { | |
2840 | ret = -EBUSY; | |
2841 | goto out; | |
2842 | } | |
2843 | cpumask_setall(tracing_reader_cpumask); | |
2844 | } else { | |
2845 | if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask)) | |
2846 | cpumask_set_cpu(cpu_file, tracing_reader_cpumask); | |
2847 | else { | |
2848 | ret = -EBUSY; | |
2849 | goto out; | |
2850 | } | |
b3806b43 SR |
2851 | } |
2852 | ||
2853 | /* create a buffer to store the information to pass to userspace */ | |
2854 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2855 | if (!iter) { |
2856 | ret = -ENOMEM; | |
2857 | goto out; | |
2858 | } | |
b3806b43 | 2859 | |
d7350c3f FW |
2860 | /* |
2861 | * We make a copy of the current tracer to avoid concurrent | |
2862 | * changes on it while we are reading. | |
2863 | */ | |
2864 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
2865 | if (!iter->trace) { | |
2866 | ret = -ENOMEM; | |
2867 | goto fail; | |
2868 | } | |
2869 | if (current_trace) | |
2870 | *iter->trace = *current_trace; | |
2871 | ||
4462344e | 2872 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 2873 | ret = -ENOMEM; |
d7350c3f | 2874 | goto fail; |
4462344e RR |
2875 | } |
2876 | ||
a309720c | 2877 | /* trace pipe does not show start of buffer */ |
4462344e | 2878 | cpumask_setall(iter->started); |
a309720c | 2879 | |
112f38a7 SR |
2880 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
2881 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2882 | ||
b04cc6b1 | 2883 | iter->cpu_file = cpu_file; |
b3806b43 | 2884 | iter->tr = &global_trace; |
d7350c3f | 2885 | mutex_init(&iter->mutex); |
b3806b43 SR |
2886 | filp->private_data = iter; |
2887 | ||
107bad8b SR |
2888 | if (iter->trace->pipe_open) |
2889 | iter->trace->pipe_open(iter); | |
107bad8b | 2890 | |
b04cc6b1 FW |
2891 | out: |
2892 | mutex_unlock(&trace_types_lock); | |
2893 | return ret; | |
d7350c3f FW |
2894 | |
2895 | fail: | |
2896 | kfree(iter->trace); | |
2897 | kfree(iter); | |
2898 | mutex_unlock(&trace_types_lock); | |
2899 | return ret; | |
b3806b43 SR |
2900 | } |
2901 | ||
2902 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2903 | { | |
2904 | struct trace_iterator *iter = file->private_data; | |
2905 | ||
b04cc6b1 FW |
2906 | mutex_lock(&trace_types_lock); |
2907 | ||
2908 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) | |
2909 | cpumask_clear(tracing_reader_cpumask); | |
2910 | else | |
2911 | cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); | |
2912 | ||
2913 | mutex_unlock(&trace_types_lock); | |
2914 | ||
4462344e | 2915 | free_cpumask_var(iter->started); |
d7350c3f FW |
2916 | mutex_destroy(&iter->mutex); |
2917 | kfree(iter->trace); | |
b3806b43 | 2918 | kfree(iter); |
b3806b43 SR |
2919 | |
2920 | return 0; | |
2921 | } | |
2922 | ||
2a2cc8f7 SSP |
2923 | static unsigned int |
2924 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2925 | { | |
2926 | struct trace_iterator *iter = filp->private_data; | |
2927 | ||
2928 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2929 | /* | |
2930 | * Always select as readable when in blocking mode | |
2931 | */ | |
2932 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2933 | } else { |
2a2cc8f7 SSP |
2934 | if (!trace_empty(iter)) |
2935 | return POLLIN | POLLRDNORM; | |
2936 | poll_wait(filp, &trace_wait, poll_table); | |
2937 | if (!trace_empty(iter)) | |
2938 | return POLLIN | POLLRDNORM; | |
2939 | ||
2940 | return 0; | |
2941 | } | |
2942 | } | |
2943 | ||
6eaaa5d5 FW |
2944 | |
2945 | void default_wait_pipe(struct trace_iterator *iter) | |
2946 | { | |
2947 | DEFINE_WAIT(wait); | |
2948 | ||
2949 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
2950 | ||
2951 | if (trace_empty(iter)) | |
2952 | schedule(); | |
2953 | ||
2954 | finish_wait(&trace_wait, &wait); | |
2955 | } | |
2956 | ||
2957 | /* | |
2958 | * This is a make-shift waitqueue. | |
2959 | * A tracer might use this callback on some rare cases: | |
2960 | * | |
2961 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
2962 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
2963 | * 2) the function tracers, trace all functions, we don't want | |
2964 | * the overhead of calling wake_up and friends | |
2965 | * (and tracing them too) | |
2966 | * | |
2967 | * Anyway, this is really very primitive wakeup. | |
2968 | */ | |
2969 | void poll_wait_pipe(struct trace_iterator *iter) | |
2970 | { | |
2971 | set_current_state(TASK_INTERRUPTIBLE); | |
2972 | /* sleep for 100 msecs, and try again. */ | |
2973 | schedule_timeout(HZ / 10); | |
2974 | } | |
2975 | ||
ff98781b EGM |
2976 | /* Must be called with trace_types_lock mutex held. */ |
2977 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
2978 | { |
2979 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 2980 | |
b3806b43 | 2981 | while (trace_empty(iter)) { |
2dc8f095 | 2982 | |
107bad8b | 2983 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 2984 | return -EAGAIN; |
107bad8b | 2985 | } |
2dc8f095 | 2986 | |
d7350c3f | 2987 | mutex_unlock(&iter->mutex); |
107bad8b | 2988 | |
6eaaa5d5 | 2989 | iter->trace->wait_pipe(iter); |
b3806b43 | 2990 | |
d7350c3f | 2991 | mutex_lock(&iter->mutex); |
107bad8b | 2992 | |
6eaaa5d5 | 2993 | if (signal_pending(current)) |
ff98781b | 2994 | return -EINTR; |
b3806b43 SR |
2995 | |
2996 | /* | |
2997 | * We block until we read something and tracing is disabled. | |
2998 | * We still block if tracing is disabled, but we have never | |
2999 | * read anything. This allows a user to cat this file, and | |
3000 | * then enable tracing. But after we have read something, | |
3001 | * we give an EOF when tracing is again disabled. | |
3002 | * | |
3003 | * iter->pos will be 0 if we haven't read anything. | |
3004 | */ | |
3005 | if (!tracer_enabled && iter->pos) | |
3006 | break; | |
b3806b43 SR |
3007 | } |
3008 | ||
ff98781b EGM |
3009 | return 1; |
3010 | } | |
3011 | ||
3012 | /* | |
3013 | * Consumer reader. | |
3014 | */ | |
3015 | static ssize_t | |
3016 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
3017 | size_t cnt, loff_t *ppos) | |
3018 | { | |
3019 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 3020 | static struct tracer *old_tracer; |
ff98781b EGM |
3021 | ssize_t sret; |
3022 | ||
3023 | /* return any leftover data */ | |
3024 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
3025 | if (sret != -EBUSY) | |
3026 | return sret; | |
3027 | ||
f9520750 | 3028 | trace_seq_init(&iter->seq); |
ff98781b | 3029 | |
d7350c3f | 3030 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 3031 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3032 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3033 | old_tracer = current_trace; | |
3034 | *iter->trace = *current_trace; | |
3035 | } | |
3036 | mutex_unlock(&trace_types_lock); | |
3037 | ||
3038 | /* | |
3039 | * Avoid more than one consumer on a single file descriptor | |
3040 | * This is just a matter of traces coherency, the ring buffer itself | |
3041 | * is protected. | |
3042 | */ | |
3043 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
3044 | if (iter->trace->read) { |
3045 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
3046 | if (sret) | |
3047 | goto out; | |
3048 | } | |
3049 | ||
3050 | waitagain: | |
3051 | sret = tracing_wait_pipe(filp); | |
3052 | if (sret <= 0) | |
3053 | goto out; | |
3054 | ||
b3806b43 | 3055 | /* stop when tracing is finished */ |
ff98781b EGM |
3056 | if (trace_empty(iter)) { |
3057 | sret = 0; | |
107bad8b | 3058 | goto out; |
ff98781b | 3059 | } |
b3806b43 SR |
3060 | |
3061 | if (cnt >= PAGE_SIZE) | |
3062 | cnt = PAGE_SIZE - 1; | |
3063 | ||
53d0aa77 | 3064 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
3065 | memset(&iter->seq, 0, |
3066 | sizeof(struct trace_iterator) - | |
3067 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 3068 | iter->pos = -1; |
b3806b43 | 3069 | |
4f535968 | 3070 | trace_event_read_lock(); |
088b1e42 | 3071 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 3072 | enum print_line_t ret; |
088b1e42 SR |
3073 | int len = iter->seq.len; |
3074 | ||
f9896bf3 | 3075 | ret = print_trace_line(iter); |
2c4f035f | 3076 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
3077 | /* don't print partial lines */ |
3078 | iter->seq.len = len; | |
b3806b43 | 3079 | break; |
088b1e42 | 3080 | } |
b91facc3 FW |
3081 | if (ret != TRACE_TYPE_NO_CONSUME) |
3082 | trace_consume(iter); | |
b3806b43 SR |
3083 | |
3084 | if (iter->seq.len >= cnt) | |
3085 | break; | |
b3806b43 | 3086 | } |
4f535968 | 3087 | trace_event_read_unlock(); |
b3806b43 | 3088 | |
b3806b43 | 3089 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3090 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3091 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3092 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3093 | |
3094 | /* | |
3095 | * If there was nothing to send to user, inspite of consuming trace | |
3096 | * entries, go back to wait for more entries. | |
3097 | */ | |
6c6c2796 | 3098 | if (sret == -EBUSY) |
9ff4b974 | 3099 | goto waitagain; |
b3806b43 | 3100 | |
107bad8b | 3101 | out: |
d7350c3f | 3102 | mutex_unlock(&iter->mutex); |
107bad8b | 3103 | |
6c6c2796 | 3104 | return sret; |
b3806b43 SR |
3105 | } |
3106 | ||
3c56819b EGM |
3107 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3108 | struct pipe_buffer *buf) | |
3109 | { | |
3110 | __free_page(buf->page); | |
3111 | } | |
3112 | ||
3113 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3114 | unsigned int idx) | |
3115 | { | |
3116 | __free_page(spd->pages[idx]); | |
3117 | } | |
3118 | ||
3119 | static struct pipe_buf_operations tracing_pipe_buf_ops = { | |
34cd4998 SR |
3120 | .can_merge = 0, |
3121 | .map = generic_pipe_buf_map, | |
3122 | .unmap = generic_pipe_buf_unmap, | |
3123 | .confirm = generic_pipe_buf_confirm, | |
3124 | .release = tracing_pipe_buf_release, | |
3125 | .steal = generic_pipe_buf_steal, | |
3126 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3127 | }; |
3128 | ||
34cd4998 | 3129 | static size_t |
fa7c7f6e | 3130 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3131 | { |
3132 | size_t count; | |
3133 | int ret; | |
3134 | ||
3135 | /* Seq buffer is page-sized, exactly what we need. */ | |
3136 | for (;;) { | |
3137 | count = iter->seq.len; | |
3138 | ret = print_trace_line(iter); | |
3139 | count = iter->seq.len - count; | |
3140 | if (rem < count) { | |
3141 | rem = 0; | |
3142 | iter->seq.len -= count; | |
3143 | break; | |
3144 | } | |
3145 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3146 | iter->seq.len -= count; | |
3147 | break; | |
3148 | } | |
3149 | ||
74e7ff8c LJ |
3150 | if (ret != TRACE_TYPE_NO_CONSUME) |
3151 | trace_consume(iter); | |
34cd4998 SR |
3152 | rem -= count; |
3153 | if (!find_next_entry_inc(iter)) { | |
3154 | rem = 0; | |
3155 | iter->ent = NULL; | |
3156 | break; | |
3157 | } | |
3158 | } | |
3159 | ||
3160 | return rem; | |
3161 | } | |
3162 | ||
3c56819b EGM |
3163 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3164 | loff_t *ppos, | |
3165 | struct pipe_inode_info *pipe, | |
3166 | size_t len, | |
3167 | unsigned int flags) | |
3168 | { | |
3169 | struct page *pages[PIPE_BUFFERS]; | |
3170 | struct partial_page partial[PIPE_BUFFERS]; | |
3171 | struct trace_iterator *iter = filp->private_data; | |
3172 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
3173 | .pages = pages, |
3174 | .partial = partial, | |
3175 | .nr_pages = 0, /* This gets updated below. */ | |
3176 | .flags = flags, | |
3177 | .ops = &tracing_pipe_buf_ops, | |
3178 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3179 | }; |
d7350c3f | 3180 | static struct tracer *old_tracer; |
3c56819b | 3181 | ssize_t ret; |
34cd4998 | 3182 | size_t rem; |
3c56819b EGM |
3183 | unsigned int i; |
3184 | ||
d7350c3f | 3185 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3186 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3187 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3188 | old_tracer = current_trace; | |
3189 | *iter->trace = *current_trace; | |
3190 | } | |
3191 | mutex_unlock(&trace_types_lock); | |
3192 | ||
3193 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3194 | |
3195 | if (iter->trace->splice_read) { | |
3196 | ret = iter->trace->splice_read(iter, filp, | |
3197 | ppos, pipe, len, flags); | |
3198 | if (ret) | |
34cd4998 | 3199 | goto out_err; |
3c56819b EGM |
3200 | } |
3201 | ||
3202 | ret = tracing_wait_pipe(filp); | |
3203 | if (ret <= 0) | |
34cd4998 | 3204 | goto out_err; |
3c56819b EGM |
3205 | |
3206 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
3207 | ret = -EFAULT; | |
34cd4998 | 3208 | goto out_err; |
3c56819b EGM |
3209 | } |
3210 | ||
4f535968 LJ |
3211 | trace_event_read_lock(); |
3212 | ||
3c56819b EGM |
3213 | /* Fill as many pages as possible. */ |
3214 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
3215 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
3216 | if (!pages[i]) |
3217 | break; | |
3c56819b | 3218 | |
fa7c7f6e | 3219 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3220 | |
3221 | /* Copy the data into the page, so we can start over. */ | |
3222 | ret = trace_seq_to_buffer(&iter->seq, | |
3223 | page_address(pages[i]), | |
3224 | iter->seq.len); | |
3225 | if (ret < 0) { | |
3226 | __free_page(pages[i]); | |
3227 | break; | |
3228 | } | |
3229 | partial[i].offset = 0; | |
3230 | partial[i].len = iter->seq.len; | |
3231 | ||
f9520750 | 3232 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3233 | } |
3234 | ||
4f535968 | 3235 | trace_event_read_unlock(); |
d7350c3f | 3236 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3237 | |
3238 | spd.nr_pages = i; | |
3239 | ||
3240 | return splice_to_pipe(pipe, &spd); | |
3241 | ||
34cd4998 | 3242 | out_err: |
d7350c3f | 3243 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3244 | |
3245 | return ret; | |
3246 | } | |
3247 | ||
a98a3c3f SR |
3248 | static ssize_t |
3249 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3250 | size_t cnt, loff_t *ppos) | |
3251 | { | |
3252 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3253 | char buf[96]; |
a98a3c3f SR |
3254 | int r; |
3255 | ||
db526ca3 SR |
3256 | mutex_lock(&trace_types_lock); |
3257 | if (!ring_buffer_expanded) | |
3258 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3259 | tr->entries >> 10, | |
3260 | trace_buf_size >> 10); | |
3261 | else | |
3262 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3263 | mutex_unlock(&trace_types_lock); | |
3264 | ||
a98a3c3f SR |
3265 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3266 | } | |
3267 | ||
3268 | static ssize_t | |
3269 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3270 | size_t cnt, loff_t *ppos) | |
3271 | { | |
3272 | unsigned long val; | |
3273 | char buf[64]; | |
bf5e6519 | 3274 | int ret, cpu; |
a98a3c3f | 3275 | |
cffae437 SR |
3276 | if (cnt >= sizeof(buf)) |
3277 | return -EINVAL; | |
a98a3c3f SR |
3278 | |
3279 | if (copy_from_user(&buf, ubuf, cnt)) | |
3280 | return -EFAULT; | |
3281 | ||
3282 | buf[cnt] = 0; | |
3283 | ||
c6caeeb1 SR |
3284 | ret = strict_strtoul(buf, 10, &val); |
3285 | if (ret < 0) | |
3286 | return ret; | |
a98a3c3f SR |
3287 | |
3288 | /* must have at least 1 entry */ | |
3289 | if (!val) | |
3290 | return -EINVAL; | |
3291 | ||
3292 | mutex_lock(&trace_types_lock); | |
3293 | ||
c76f0694 | 3294 | tracing_stop(); |
a98a3c3f | 3295 | |
bf5e6519 SR |
3296 | /* disable all cpu buffers */ |
3297 | for_each_tracing_cpu(cpu) { | |
3298 | if (global_trace.data[cpu]) | |
3299 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3300 | if (max_tr.data[cpu]) | |
3301 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3302 | } | |
3303 | ||
1696b2b0 SR |
3304 | /* value is in KB */ |
3305 | val <<= 10; | |
3306 | ||
3928a8a2 | 3307 | if (val != global_trace.entries) { |
73c5162a | 3308 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3309 | if (ret < 0) { |
3310 | cnt = ret; | |
3eefae99 SR |
3311 | goto out; |
3312 | } | |
a98a3c3f SR |
3313 | } |
3314 | ||
3315 | filp->f_pos += cnt; | |
3316 | ||
19384c03 SR |
3317 | /* If check pages failed, return ENOMEM */ |
3318 | if (tracing_disabled) | |
3319 | cnt = -ENOMEM; | |
a98a3c3f | 3320 | out: |
bf5e6519 SR |
3321 | for_each_tracing_cpu(cpu) { |
3322 | if (global_trace.data[cpu]) | |
3323 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3324 | if (max_tr.data[cpu]) | |
3325 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3326 | } | |
3327 | ||
c76f0694 | 3328 | tracing_start(); |
a98a3c3f SR |
3329 | max_tr.entries = global_trace.entries; |
3330 | mutex_unlock(&trace_types_lock); | |
3331 | ||
3332 | return cnt; | |
3333 | } | |
3334 | ||
5bf9a1ee PP |
3335 | static int mark_printk(const char *fmt, ...) |
3336 | { | |
3337 | int ret; | |
3338 | va_list args; | |
3339 | va_start(args, fmt); | |
40ce74f1 | 3340 | ret = trace_vprintk(0, fmt, args); |
5bf9a1ee PP |
3341 | va_end(args); |
3342 | return ret; | |
3343 | } | |
3344 | ||
3345 | static ssize_t | |
3346 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3347 | size_t cnt, loff_t *fpos) | |
3348 | { | |
3349 | char *buf; | |
3350 | char *end; | |
5bf9a1ee | 3351 | |
c76f0694 | 3352 | if (tracing_disabled) |
5bf9a1ee PP |
3353 | return -EINVAL; |
3354 | ||
3355 | if (cnt > TRACE_BUF_SIZE) | |
3356 | cnt = TRACE_BUF_SIZE; | |
3357 | ||
3358 | buf = kmalloc(cnt + 1, GFP_KERNEL); | |
3359 | if (buf == NULL) | |
3360 | return -ENOMEM; | |
3361 | ||
3362 | if (copy_from_user(buf, ubuf, cnt)) { | |
3363 | kfree(buf); | |
3364 | return -EFAULT; | |
3365 | } | |
3366 | ||
3367 | /* Cut from the first nil or newline. */ | |
3368 | buf[cnt] = '\0'; | |
3369 | end = strchr(buf, '\n'); | |
3370 | if (end) | |
3371 | *end = '\0'; | |
3372 | ||
3373 | cnt = mark_printk("%s\n", buf); | |
3374 | kfree(buf); | |
3375 | *fpos += cnt; | |
3376 | ||
3377 | return cnt; | |
3378 | } | |
3379 | ||
5079f326 Z |
3380 | static ssize_t tracing_clock_read(struct file *filp, char __user *ubuf, |
3381 | size_t cnt, loff_t *ppos) | |
3382 | { | |
3383 | char buf[64]; | |
3384 | int bufiter = 0; | |
3385 | int i; | |
3386 | ||
3387 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
3388 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, | |
3389 | "%s%s%s%s", i ? " " : "", | |
3390 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3391 | i == trace_clock_id ? "]" : ""); | |
3392 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, "\n"); | |
3393 | ||
3394 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, bufiter); | |
3395 | } | |
3396 | ||
3397 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
3398 | size_t cnt, loff_t *fpos) | |
3399 | { | |
3400 | char buf[64]; | |
3401 | const char *clockstr; | |
3402 | int i; | |
3403 | ||
3404 | if (cnt >= sizeof(buf)) | |
3405 | return -EINVAL; | |
3406 | ||
3407 | if (copy_from_user(&buf, ubuf, cnt)) | |
3408 | return -EFAULT; | |
3409 | ||
3410 | buf[cnt] = 0; | |
3411 | ||
3412 | clockstr = strstrip(buf); | |
3413 | ||
3414 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
3415 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
3416 | break; | |
3417 | } | |
3418 | if (i == ARRAY_SIZE(trace_clocks)) | |
3419 | return -EINVAL; | |
3420 | ||
3421 | trace_clock_id = i; | |
3422 | ||
3423 | mutex_lock(&trace_types_lock); | |
3424 | ||
3425 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
3426 | if (max_tr.buffer) | |
3427 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
3428 | ||
3429 | mutex_unlock(&trace_types_lock); | |
3430 | ||
3431 | *fpos += cnt; | |
3432 | ||
3433 | return cnt; | |
3434 | } | |
3435 | ||
5e2336a0 | 3436 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3437 | .open = tracing_open_generic, |
3438 | .read = tracing_max_lat_read, | |
3439 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
3440 | }; |
3441 | ||
5e2336a0 | 3442 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3443 | .open = tracing_open_generic, |
3444 | .read = tracing_ctrl_read, | |
3445 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
3446 | }; |
3447 | ||
5e2336a0 | 3448 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3449 | .open = tracing_open_generic, |
3450 | .read = tracing_set_trace_read, | |
3451 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
3452 | }; |
3453 | ||
5e2336a0 | 3454 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3455 | .open = tracing_open_pipe, |
2a2cc8f7 | 3456 | .poll = tracing_poll_pipe, |
4bf39a94 | 3457 | .read = tracing_read_pipe, |
3c56819b | 3458 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3459 | .release = tracing_release_pipe, |
b3806b43 SR |
3460 | }; |
3461 | ||
5e2336a0 | 3462 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3463 | .open = tracing_open_generic, |
3464 | .read = tracing_entries_read, | |
3465 | .write = tracing_entries_write, | |
3466 | }; | |
3467 | ||
5e2336a0 | 3468 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3469 | .open = tracing_open_generic, |
5bf9a1ee PP |
3470 | .write = tracing_mark_write, |
3471 | }; | |
3472 | ||
5079f326 Z |
3473 | static const struct file_operations trace_clock_fops = { |
3474 | .open = tracing_open_generic, | |
3475 | .read = tracing_clock_read, | |
3476 | .write = tracing_clock_write, | |
3477 | }; | |
3478 | ||
2cadf913 SR |
3479 | struct ftrace_buffer_info { |
3480 | struct trace_array *tr; | |
3481 | void *spare; | |
3482 | int cpu; | |
3483 | unsigned int read; | |
3484 | }; | |
3485 | ||
3486 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3487 | { | |
3488 | int cpu = (int)(long)inode->i_private; | |
3489 | struct ftrace_buffer_info *info; | |
3490 | ||
3491 | if (tracing_disabled) | |
3492 | return -ENODEV; | |
3493 | ||
3494 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3495 | if (!info) | |
3496 | return -ENOMEM; | |
3497 | ||
3498 | info->tr = &global_trace; | |
3499 | info->cpu = cpu; | |
ddd538f3 | 3500 | info->spare = NULL; |
2cadf913 SR |
3501 | /* Force reading ring buffer for first read */ |
3502 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3503 | |
3504 | filp->private_data = info; | |
3505 | ||
d1e7e02f | 3506 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3507 | } |
3508 | ||
3509 | static ssize_t | |
3510 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3511 | size_t count, loff_t *ppos) | |
3512 | { | |
3513 | struct ftrace_buffer_info *info = filp->private_data; | |
3514 | unsigned int pos; | |
3515 | ssize_t ret; | |
3516 | size_t size; | |
3517 | ||
2dc5d12b SR |
3518 | if (!count) |
3519 | return 0; | |
3520 | ||
ddd538f3 LJ |
3521 | if (!info->spare) |
3522 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3523 | if (!info->spare) | |
3524 | return -ENOMEM; | |
3525 | ||
2cadf913 SR |
3526 | /* Do we have previous read data to read? */ |
3527 | if (info->read < PAGE_SIZE) | |
3528 | goto read; | |
3529 | ||
3530 | info->read = 0; | |
3531 | ||
3532 | ret = ring_buffer_read_page(info->tr->buffer, | |
3533 | &info->spare, | |
3534 | count, | |
3535 | info->cpu, 0); | |
3536 | if (ret < 0) | |
3537 | return 0; | |
3538 | ||
3539 | pos = ring_buffer_page_len(info->spare); | |
3540 | ||
3541 | if (pos < PAGE_SIZE) | |
3542 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3543 | ||
3544 | read: | |
3545 | size = PAGE_SIZE - info->read; | |
3546 | if (size > count) | |
3547 | size = count; | |
3548 | ||
3549 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3550 | if (ret == size) |
2cadf913 | 3551 | return -EFAULT; |
2dc5d12b SR |
3552 | size -= ret; |
3553 | ||
2cadf913 SR |
3554 | *ppos += size; |
3555 | info->read += size; | |
3556 | ||
3557 | return size; | |
3558 | } | |
3559 | ||
3560 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3561 | { | |
3562 | struct ftrace_buffer_info *info = file->private_data; | |
3563 | ||
ddd538f3 LJ |
3564 | if (info->spare) |
3565 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3566 | kfree(info); |
3567 | ||
3568 | return 0; | |
3569 | } | |
3570 | ||
3571 | struct buffer_ref { | |
3572 | struct ring_buffer *buffer; | |
3573 | void *page; | |
3574 | int ref; | |
3575 | }; | |
3576 | ||
3577 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3578 | struct pipe_buffer *buf) | |
3579 | { | |
3580 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3581 | ||
3582 | if (--ref->ref) | |
3583 | return; | |
3584 | ||
3585 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3586 | kfree(ref); | |
3587 | buf->private = 0; | |
3588 | } | |
3589 | ||
3590 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3591 | struct pipe_buffer *buf) | |
3592 | { | |
3593 | return 1; | |
3594 | } | |
3595 | ||
3596 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3597 | struct pipe_buffer *buf) | |
3598 | { | |
3599 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3600 | ||
3601 | ref->ref++; | |
3602 | } | |
3603 | ||
3604 | /* Pipe buffer operations for a buffer. */ | |
3605 | static struct pipe_buf_operations buffer_pipe_buf_ops = { | |
3606 | .can_merge = 0, | |
3607 | .map = generic_pipe_buf_map, | |
3608 | .unmap = generic_pipe_buf_unmap, | |
3609 | .confirm = generic_pipe_buf_confirm, | |
3610 | .release = buffer_pipe_buf_release, | |
3611 | .steal = buffer_pipe_buf_steal, | |
3612 | .get = buffer_pipe_buf_get, | |
3613 | }; | |
3614 | ||
3615 | /* | |
3616 | * Callback from splice_to_pipe(), if we need to release some pages | |
3617 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3618 | */ | |
3619 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3620 | { | |
3621 | struct buffer_ref *ref = | |
3622 | (struct buffer_ref *)spd->partial[i].private; | |
3623 | ||
3624 | if (--ref->ref) | |
3625 | return; | |
3626 | ||
3627 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3628 | kfree(ref); | |
3629 | spd->partial[i].private = 0; | |
3630 | } | |
3631 | ||
3632 | static ssize_t | |
3633 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3634 | struct pipe_inode_info *pipe, size_t len, | |
3635 | unsigned int flags) | |
3636 | { | |
3637 | struct ftrace_buffer_info *info = file->private_data; | |
3638 | struct partial_page partial[PIPE_BUFFERS]; | |
3639 | struct page *pages[PIPE_BUFFERS]; | |
3640 | struct splice_pipe_desc spd = { | |
3641 | .pages = pages, | |
3642 | .partial = partial, | |
3643 | .flags = flags, | |
3644 | .ops = &buffer_pipe_buf_ops, | |
3645 | .spd_release = buffer_spd_release, | |
3646 | }; | |
3647 | struct buffer_ref *ref; | |
93459c6c | 3648 | int entries, size, i; |
2cadf913 SR |
3649 | size_t ret; |
3650 | ||
93cfb3c9 LJ |
3651 | if (*ppos & (PAGE_SIZE - 1)) { |
3652 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
3653 | return -EINVAL; | |
3654 | } | |
3655 | ||
3656 | if (len & (PAGE_SIZE - 1)) { | |
3657 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
3658 | if (len < PAGE_SIZE) | |
3659 | return -EINVAL; | |
3660 | len &= PAGE_MASK; | |
3661 | } | |
3662 | ||
93459c6c SR |
3663 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
3664 | ||
3665 | for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) { | |
2cadf913 SR |
3666 | struct page *page; |
3667 | int r; | |
3668 | ||
3669 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3670 | if (!ref) | |
3671 | break; | |
3672 | ||
7267fa68 | 3673 | ref->ref = 1; |
2cadf913 SR |
3674 | ref->buffer = info->tr->buffer; |
3675 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3676 | if (!ref->page) { | |
3677 | kfree(ref); | |
3678 | break; | |
3679 | } | |
3680 | ||
3681 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 3682 | len, info->cpu, 1); |
2cadf913 SR |
3683 | if (r < 0) { |
3684 | ring_buffer_free_read_page(ref->buffer, | |
3685 | ref->page); | |
3686 | kfree(ref); | |
3687 | break; | |
3688 | } | |
3689 | ||
3690 | /* | |
3691 | * zero out any left over data, this is going to | |
3692 | * user land. | |
3693 | */ | |
3694 | size = ring_buffer_page_len(ref->page); | |
3695 | if (size < PAGE_SIZE) | |
3696 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3697 | ||
3698 | page = virt_to_page(ref->page); | |
3699 | ||
3700 | spd.pages[i] = page; | |
3701 | spd.partial[i].len = PAGE_SIZE; | |
3702 | spd.partial[i].offset = 0; | |
3703 | spd.partial[i].private = (unsigned long)ref; | |
3704 | spd.nr_pages++; | |
93cfb3c9 | 3705 | *ppos += PAGE_SIZE; |
93459c6c SR |
3706 | |
3707 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
3708 | } |
3709 | ||
3710 | spd.nr_pages = i; | |
3711 | ||
3712 | /* did we read anything? */ | |
3713 | if (!spd.nr_pages) { | |
3714 | if (flags & SPLICE_F_NONBLOCK) | |
3715 | ret = -EAGAIN; | |
3716 | else | |
3717 | ret = 0; | |
3718 | /* TODO: block */ | |
3719 | return ret; | |
3720 | } | |
3721 | ||
3722 | ret = splice_to_pipe(pipe, &spd); | |
3723 | ||
3724 | return ret; | |
3725 | } | |
3726 | ||
3727 | static const struct file_operations tracing_buffers_fops = { | |
3728 | .open = tracing_buffers_open, | |
3729 | .read = tracing_buffers_read, | |
3730 | .release = tracing_buffers_release, | |
3731 | .splice_read = tracing_buffers_splice_read, | |
3732 | .llseek = no_llseek, | |
3733 | }; | |
3734 | ||
c8d77183 SR |
3735 | static ssize_t |
3736 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
3737 | size_t count, loff_t *ppos) | |
3738 | { | |
3739 | unsigned long cpu = (unsigned long)filp->private_data; | |
3740 | struct trace_array *tr = &global_trace; | |
3741 | struct trace_seq *s; | |
3742 | unsigned long cnt; | |
3743 | ||
e4f2d10f | 3744 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 SR |
3745 | if (!s) |
3746 | return ENOMEM; | |
3747 | ||
3748 | trace_seq_init(s); | |
3749 | ||
3750 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
3751 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
3752 | ||
3753 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
3754 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
3755 | ||
3756 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
3757 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
3758 | ||
c8d77183 SR |
3759 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
3760 | ||
3761 | kfree(s); | |
3762 | ||
3763 | return count; | |
3764 | } | |
3765 | ||
3766 | static const struct file_operations tracing_stats_fops = { | |
3767 | .open = tracing_open_generic, | |
3768 | .read = tracing_stats_read, | |
3769 | }; | |
3770 | ||
bc0c38d1 SR |
3771 | #ifdef CONFIG_DYNAMIC_FTRACE |
3772 | ||
b807c3d0 SR |
3773 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3774 | { | |
3775 | return 0; | |
3776 | } | |
3777 | ||
bc0c38d1 | 3778 | static ssize_t |
b807c3d0 | 3779 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3780 | size_t cnt, loff_t *ppos) |
3781 | { | |
a26a2a27 SR |
3782 | static char ftrace_dyn_info_buffer[1024]; |
3783 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3784 | unsigned long *p = filp->private_data; |
b807c3d0 | 3785 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3786 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3787 | int r; |
3788 | ||
b807c3d0 SR |
3789 | mutex_lock(&dyn_info_mutex); |
3790 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3791 | |
a26a2a27 | 3792 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3793 | buf[r++] = '\n'; |
3794 | ||
3795 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3796 | ||
3797 | mutex_unlock(&dyn_info_mutex); | |
3798 | ||
3799 | return r; | |
bc0c38d1 SR |
3800 | } |
3801 | ||
5e2336a0 | 3802 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3803 | .open = tracing_open_generic, |
b807c3d0 | 3804 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3805 | }; |
3806 | #endif | |
3807 | ||
3808 | static struct dentry *d_tracer; | |
3809 | ||
3810 | struct dentry *tracing_init_dentry(void) | |
3811 | { | |
3812 | static int once; | |
3813 | ||
3814 | if (d_tracer) | |
3815 | return d_tracer; | |
3816 | ||
3e1f60b8 FW |
3817 | if (!debugfs_initialized()) |
3818 | return NULL; | |
3819 | ||
bc0c38d1 SR |
3820 | d_tracer = debugfs_create_dir("tracing", NULL); |
3821 | ||
3822 | if (!d_tracer && !once) { | |
3823 | once = 1; | |
3824 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3825 | return NULL; | |
3826 | } | |
3827 | ||
3828 | return d_tracer; | |
3829 | } | |
3830 | ||
b04cc6b1 FW |
3831 | static struct dentry *d_percpu; |
3832 | ||
3833 | struct dentry *tracing_dentry_percpu(void) | |
3834 | { | |
3835 | static int once; | |
3836 | struct dentry *d_tracer; | |
3837 | ||
3838 | if (d_percpu) | |
3839 | return d_percpu; | |
3840 | ||
3841 | d_tracer = tracing_init_dentry(); | |
3842 | ||
3843 | if (!d_tracer) | |
3844 | return NULL; | |
3845 | ||
3846 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
3847 | ||
3848 | if (!d_percpu && !once) { | |
3849 | once = 1; | |
3850 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
3851 | return NULL; | |
3852 | } | |
3853 | ||
3854 | return d_percpu; | |
3855 | } | |
3856 | ||
3857 | static void tracing_init_debugfs_percpu(long cpu) | |
3858 | { | |
3859 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 3860 | struct dentry *d_cpu; |
8656e7a2 FW |
3861 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ |
3862 | char cpu_dir[7]; | |
b04cc6b1 FW |
3863 | |
3864 | if (cpu > 999 || cpu < 0) | |
3865 | return; | |
3866 | ||
8656e7a2 FW |
3867 | sprintf(cpu_dir, "cpu%ld", cpu); |
3868 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
3869 | if (!d_cpu) { | |
3870 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
3871 | return; | |
3872 | } | |
b04cc6b1 | 3873 | |
8656e7a2 | 3874 | /* per cpu trace_pipe */ |
5452af66 FW |
3875 | trace_create_file("trace_pipe", 0444, d_cpu, |
3876 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
3877 | |
3878 | /* per cpu trace */ | |
5452af66 FW |
3879 | trace_create_file("trace", 0644, d_cpu, |
3880 | (void *) cpu, &tracing_fops); | |
7f96f93f | 3881 | |
5452af66 FW |
3882 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
3883 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 3884 | |
c8d77183 SR |
3885 | trace_create_file("stats", 0444, d_cpu, |
3886 | (void *) cpu, &tracing_stats_fops); | |
b04cc6b1 FW |
3887 | } |
3888 | ||
60a11774 SR |
3889 | #ifdef CONFIG_FTRACE_SELFTEST |
3890 | /* Let selftest have access to static functions in this file */ | |
3891 | #include "trace_selftest.c" | |
3892 | #endif | |
3893 | ||
577b785f SR |
3894 | struct trace_option_dentry { |
3895 | struct tracer_opt *opt; | |
3896 | struct tracer_flags *flags; | |
3897 | struct dentry *entry; | |
3898 | }; | |
3899 | ||
3900 | static ssize_t | |
3901 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3902 | loff_t *ppos) | |
3903 | { | |
3904 | struct trace_option_dentry *topt = filp->private_data; | |
3905 | char *buf; | |
3906 | ||
3907 | if (topt->flags->val & topt->opt->bit) | |
3908 | buf = "1\n"; | |
3909 | else | |
3910 | buf = "0\n"; | |
3911 | ||
3912 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3913 | } | |
3914 | ||
3915 | static ssize_t | |
3916 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3917 | loff_t *ppos) | |
3918 | { | |
3919 | struct trace_option_dentry *topt = filp->private_data; | |
3920 | unsigned long val; | |
3921 | char buf[64]; | |
3922 | int ret; | |
3923 | ||
3924 | if (cnt >= sizeof(buf)) | |
3925 | return -EINVAL; | |
3926 | ||
3927 | if (copy_from_user(&buf, ubuf, cnt)) | |
3928 | return -EFAULT; | |
3929 | ||
3930 | buf[cnt] = 0; | |
3931 | ||
3932 | ret = strict_strtoul(buf, 10, &val); | |
3933 | if (ret < 0) | |
3934 | return ret; | |
3935 | ||
3936 | ret = 0; | |
3937 | switch (val) { | |
3938 | case 0: | |
3939 | /* do nothing if already cleared */ | |
3940 | if (!(topt->flags->val & topt->opt->bit)) | |
3941 | break; | |
3942 | ||
3943 | mutex_lock(&trace_types_lock); | |
3944 | if (current_trace->set_flag) | |
3945 | ret = current_trace->set_flag(topt->flags->val, | |
3946 | topt->opt->bit, 0); | |
3947 | mutex_unlock(&trace_types_lock); | |
3948 | if (ret) | |
3949 | return ret; | |
3950 | topt->flags->val &= ~topt->opt->bit; | |
3951 | break; | |
3952 | case 1: | |
3953 | /* do nothing if already set */ | |
3954 | if (topt->flags->val & topt->opt->bit) | |
3955 | break; | |
3956 | ||
3957 | mutex_lock(&trace_types_lock); | |
3958 | if (current_trace->set_flag) | |
3959 | ret = current_trace->set_flag(topt->flags->val, | |
3960 | topt->opt->bit, 1); | |
3961 | mutex_unlock(&trace_types_lock); | |
3962 | if (ret) | |
3963 | return ret; | |
3964 | topt->flags->val |= topt->opt->bit; | |
3965 | break; | |
3966 | ||
3967 | default: | |
3968 | return -EINVAL; | |
3969 | } | |
3970 | ||
3971 | *ppos += cnt; | |
3972 | ||
3973 | return cnt; | |
3974 | } | |
3975 | ||
3976 | ||
3977 | static const struct file_operations trace_options_fops = { | |
3978 | .open = tracing_open_generic, | |
3979 | .read = trace_options_read, | |
3980 | .write = trace_options_write, | |
3981 | }; | |
3982 | ||
a8259075 SR |
3983 | static ssize_t |
3984 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3985 | loff_t *ppos) | |
3986 | { | |
3987 | long index = (long)filp->private_data; | |
3988 | char *buf; | |
3989 | ||
3990 | if (trace_flags & (1 << index)) | |
3991 | buf = "1\n"; | |
3992 | else | |
3993 | buf = "0\n"; | |
3994 | ||
3995 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3996 | } | |
3997 | ||
3998 | static ssize_t | |
3999 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4000 | loff_t *ppos) | |
4001 | { | |
4002 | long index = (long)filp->private_data; | |
4003 | char buf[64]; | |
4004 | unsigned long val; | |
4005 | int ret; | |
4006 | ||
4007 | if (cnt >= sizeof(buf)) | |
4008 | return -EINVAL; | |
4009 | ||
4010 | if (copy_from_user(&buf, ubuf, cnt)) | |
4011 | return -EFAULT; | |
4012 | ||
4013 | buf[cnt] = 0; | |
4014 | ||
4015 | ret = strict_strtoul(buf, 10, &val); | |
4016 | if (ret < 0) | |
4017 | return ret; | |
4018 | ||
f2d84b65 | 4019 | if (val != 0 && val != 1) |
a8259075 | 4020 | return -EINVAL; |
f2d84b65 | 4021 | set_tracer_flags(1 << index, val); |
a8259075 SR |
4022 | |
4023 | *ppos += cnt; | |
4024 | ||
4025 | return cnt; | |
4026 | } | |
4027 | ||
a8259075 SR |
4028 | static const struct file_operations trace_options_core_fops = { |
4029 | .open = tracing_open_generic, | |
4030 | .read = trace_options_core_read, | |
4031 | .write = trace_options_core_write, | |
4032 | }; | |
4033 | ||
5452af66 FW |
4034 | struct dentry *trace_create_file(const char *name, |
4035 | mode_t mode, | |
4036 | struct dentry *parent, | |
4037 | void *data, | |
4038 | const struct file_operations *fops) | |
4039 | { | |
4040 | struct dentry *ret; | |
4041 | ||
4042 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
4043 | if (!ret) | |
4044 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
4045 | ||
4046 | return ret; | |
4047 | } | |
4048 | ||
4049 | ||
a8259075 SR |
4050 | static struct dentry *trace_options_init_dentry(void) |
4051 | { | |
4052 | struct dentry *d_tracer; | |
4053 | static struct dentry *t_options; | |
4054 | ||
4055 | if (t_options) | |
4056 | return t_options; | |
4057 | ||
4058 | d_tracer = tracing_init_dentry(); | |
4059 | if (!d_tracer) | |
4060 | return NULL; | |
4061 | ||
4062 | t_options = debugfs_create_dir("options", d_tracer); | |
4063 | if (!t_options) { | |
4064 | pr_warning("Could not create debugfs directory 'options'\n"); | |
4065 | return NULL; | |
4066 | } | |
4067 | ||
4068 | return t_options; | |
4069 | } | |
4070 | ||
577b785f SR |
4071 | static void |
4072 | create_trace_option_file(struct trace_option_dentry *topt, | |
4073 | struct tracer_flags *flags, | |
4074 | struct tracer_opt *opt) | |
4075 | { | |
4076 | struct dentry *t_options; | |
577b785f SR |
4077 | |
4078 | t_options = trace_options_init_dentry(); | |
4079 | if (!t_options) | |
4080 | return; | |
4081 | ||
4082 | topt->flags = flags; | |
4083 | topt->opt = opt; | |
4084 | ||
5452af66 | 4085 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
4086 | &trace_options_fops); |
4087 | ||
577b785f SR |
4088 | } |
4089 | ||
4090 | static struct trace_option_dentry * | |
4091 | create_trace_option_files(struct tracer *tracer) | |
4092 | { | |
4093 | struct trace_option_dentry *topts; | |
4094 | struct tracer_flags *flags; | |
4095 | struct tracer_opt *opts; | |
4096 | int cnt; | |
4097 | ||
4098 | if (!tracer) | |
4099 | return NULL; | |
4100 | ||
4101 | flags = tracer->flags; | |
4102 | ||
4103 | if (!flags || !flags->opts) | |
4104 | return NULL; | |
4105 | ||
4106 | opts = flags->opts; | |
4107 | ||
4108 | for (cnt = 0; opts[cnt].name; cnt++) | |
4109 | ; | |
4110 | ||
0cfe8245 | 4111 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
4112 | if (!topts) |
4113 | return NULL; | |
4114 | ||
4115 | for (cnt = 0; opts[cnt].name; cnt++) | |
4116 | create_trace_option_file(&topts[cnt], flags, | |
4117 | &opts[cnt]); | |
4118 | ||
4119 | return topts; | |
4120 | } | |
4121 | ||
4122 | static void | |
4123 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
4124 | { | |
4125 | int cnt; | |
4126 | ||
4127 | if (!topts) | |
4128 | return; | |
4129 | ||
4130 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
4131 | if (topts[cnt].entry) | |
4132 | debugfs_remove(topts[cnt].entry); | |
4133 | } | |
4134 | ||
4135 | kfree(topts); | |
4136 | } | |
4137 | ||
a8259075 SR |
4138 | static struct dentry * |
4139 | create_trace_option_core_file(const char *option, long index) | |
4140 | { | |
4141 | struct dentry *t_options; | |
a8259075 SR |
4142 | |
4143 | t_options = trace_options_init_dentry(); | |
4144 | if (!t_options) | |
4145 | return NULL; | |
4146 | ||
5452af66 | 4147 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 4148 | &trace_options_core_fops); |
a8259075 SR |
4149 | } |
4150 | ||
4151 | static __init void create_trace_options_dir(void) | |
4152 | { | |
4153 | struct dentry *t_options; | |
a8259075 SR |
4154 | int i; |
4155 | ||
4156 | t_options = trace_options_init_dentry(); | |
4157 | if (!t_options) | |
4158 | return; | |
4159 | ||
5452af66 FW |
4160 | for (i = 0; trace_options[i]; i++) |
4161 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4162 | } |
4163 | ||
b5ad384e | 4164 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4165 | { |
4166 | struct dentry *d_tracer; | |
b04cc6b1 | 4167 | int cpu; |
bc0c38d1 SR |
4168 | |
4169 | d_tracer = tracing_init_dentry(); | |
4170 | ||
5452af66 FW |
4171 | trace_create_file("tracing_enabled", 0644, d_tracer, |
4172 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 4173 | |
5452af66 FW |
4174 | trace_create_file("trace_options", 0644, d_tracer, |
4175 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4176 | |
5452af66 FW |
4177 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4178 | NULL, &tracing_cpumask_fops); | |
4179 | ||
4180 | trace_create_file("trace", 0644, d_tracer, | |
4181 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 4182 | |
5452af66 FW |
4183 | trace_create_file("available_tracers", 0444, d_tracer, |
4184 | &global_trace, &show_traces_fops); | |
4185 | ||
339ae5d3 | 4186 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4187 | &global_trace, &set_tracer_fops); |
4188 | ||
5d4a9dba | 4189 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
4190 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
4191 | &tracing_max_latency, &tracing_max_lat_fops); | |
4192 | ||
4193 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4194 | &tracing_thresh, &tracing_max_lat_fops); | |
5d4a9dba | 4195 | #endif |
a8259075 | 4196 | |
339ae5d3 | 4197 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4198 | NULL, &tracing_readme_fops); |
4199 | ||
4200 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4201 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4202 | |
4203 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
4204 | &global_trace, &tracing_entries_fops); | |
4205 | ||
4206 | trace_create_file("trace_marker", 0220, d_tracer, | |
4207 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4208 | |
69abe6a5 AP |
4209 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4210 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 4211 | |
5079f326 Z |
4212 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
4213 | &trace_clock_fops); | |
4214 | ||
bc0c38d1 | 4215 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4216 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4217 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4218 | #endif |
d618b3e6 IM |
4219 | #ifdef CONFIG_SYSPROF_TRACER |
4220 | init_tracer_sysprof_debugfs(d_tracer); | |
4221 | #endif | |
b04cc6b1 | 4222 | |
5452af66 FW |
4223 | create_trace_options_dir(); |
4224 | ||
b04cc6b1 FW |
4225 | for_each_tracing_cpu(cpu) |
4226 | tracing_init_debugfs_percpu(cpu); | |
4227 | ||
b5ad384e | 4228 | return 0; |
bc0c38d1 SR |
4229 | } |
4230 | ||
3f5a54e3 SR |
4231 | static int trace_panic_handler(struct notifier_block *this, |
4232 | unsigned long event, void *unused) | |
4233 | { | |
944ac425 SR |
4234 | if (ftrace_dump_on_oops) |
4235 | ftrace_dump(); | |
3f5a54e3 SR |
4236 | return NOTIFY_OK; |
4237 | } | |
4238 | ||
4239 | static struct notifier_block trace_panic_notifier = { | |
4240 | .notifier_call = trace_panic_handler, | |
4241 | .next = NULL, | |
4242 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4243 | }; | |
4244 | ||
4245 | static int trace_die_handler(struct notifier_block *self, | |
4246 | unsigned long val, | |
4247 | void *data) | |
4248 | { | |
4249 | switch (val) { | |
4250 | case DIE_OOPS: | |
944ac425 SR |
4251 | if (ftrace_dump_on_oops) |
4252 | ftrace_dump(); | |
3f5a54e3 SR |
4253 | break; |
4254 | default: | |
4255 | break; | |
4256 | } | |
4257 | return NOTIFY_OK; | |
4258 | } | |
4259 | ||
4260 | static struct notifier_block trace_die_notifier = { | |
4261 | .notifier_call = trace_die_handler, | |
4262 | .priority = 200 | |
4263 | }; | |
4264 | ||
4265 | /* | |
4266 | * printk is set to max of 1024, we really don't need it that big. | |
4267 | * Nothing should be printing 1000 characters anyway. | |
4268 | */ | |
4269 | #define TRACE_MAX_PRINT 1000 | |
4270 | ||
4271 | /* | |
4272 | * Define here KERN_TRACE so that we have one place to modify | |
4273 | * it if we decide to change what log level the ftrace dump | |
4274 | * should be at. | |
4275 | */ | |
428aee14 | 4276 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
4277 | |
4278 | static void | |
4279 | trace_printk_seq(struct trace_seq *s) | |
4280 | { | |
4281 | /* Probably should print a warning here. */ | |
4282 | if (s->len >= 1000) | |
4283 | s->len = 1000; | |
4284 | ||
4285 | /* should be zero ended, but we are paranoid. */ | |
4286 | s->buffer[s->len] = 0; | |
4287 | ||
4288 | printk(KERN_TRACE "%s", s->buffer); | |
4289 | ||
f9520750 | 4290 | trace_seq_init(s); |
3f5a54e3 SR |
4291 | } |
4292 | ||
cf586b61 | 4293 | static void __ftrace_dump(bool disable_tracing) |
3f5a54e3 | 4294 | { |
cd891ae0 SR |
4295 | static raw_spinlock_t ftrace_dump_lock = |
4296 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
3f5a54e3 SR |
4297 | /* use static because iter can be a bit big for the stack */ |
4298 | static struct trace_iterator iter; | |
cf586b61 | 4299 | unsigned int old_userobj; |
3f5a54e3 | 4300 | static int dump_ran; |
d769041f SR |
4301 | unsigned long flags; |
4302 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4303 | |
4304 | /* only one dump */ | |
cd891ae0 SR |
4305 | local_irq_save(flags); |
4306 | __raw_spin_lock(&ftrace_dump_lock); | |
3f5a54e3 SR |
4307 | if (dump_ran) |
4308 | goto out; | |
4309 | ||
4310 | dump_ran = 1; | |
4311 | ||
0ee6b6cf | 4312 | tracing_off(); |
cf586b61 FW |
4313 | |
4314 | if (disable_tracing) | |
4315 | ftrace_kill(); | |
3f5a54e3 | 4316 | |
d769041f SR |
4317 | for_each_tracing_cpu(cpu) { |
4318 | atomic_inc(&global_trace.data[cpu]->disabled); | |
4319 | } | |
4320 | ||
cf586b61 FW |
4321 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4322 | ||
b54d3de9 TE |
4323 | /* don't look at user memory in panic mode */ |
4324 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4325 | ||
3f5a54e3 SR |
4326 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
4327 | ||
e543ad76 | 4328 | /* Simulate the iterator */ |
3f5a54e3 SR |
4329 | iter.tr = &global_trace; |
4330 | iter.trace = current_trace; | |
e543ad76 | 4331 | iter.cpu_file = TRACE_PIPE_ALL_CPU; |
3f5a54e3 SR |
4332 | |
4333 | /* | |
4334 | * We need to stop all tracing on all CPUS to read the | |
4335 | * the next buffer. This is a bit expensive, but is | |
4336 | * not done often. We fill all what we can read, | |
4337 | * and then release the locks again. | |
4338 | */ | |
4339 | ||
3f5a54e3 SR |
4340 | while (!trace_empty(&iter)) { |
4341 | ||
4342 | if (!cnt) | |
4343 | printk(KERN_TRACE "---------------------------------\n"); | |
4344 | ||
4345 | cnt++; | |
4346 | ||
4347 | /* reset all but tr, trace, and overruns */ | |
4348 | memset(&iter.seq, 0, | |
4349 | sizeof(struct trace_iterator) - | |
4350 | offsetof(struct trace_iterator, seq)); | |
4351 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4352 | iter.pos = -1; | |
4353 | ||
4354 | if (find_next_entry_inc(&iter) != NULL) { | |
74e7ff8c LJ |
4355 | int ret; |
4356 | ||
4357 | ret = print_trace_line(&iter); | |
4358 | if (ret != TRACE_TYPE_NO_CONSUME) | |
4359 | trace_consume(&iter); | |
3f5a54e3 SR |
4360 | } |
4361 | ||
4362 | trace_printk_seq(&iter.seq); | |
4363 | } | |
4364 | ||
4365 | if (!cnt) | |
4366 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4367 | else | |
4368 | printk(KERN_TRACE "---------------------------------\n"); | |
4369 | ||
cf586b61 FW |
4370 | /* Re-enable tracing if requested */ |
4371 | if (!disable_tracing) { | |
4372 | trace_flags |= old_userobj; | |
4373 | ||
4374 | for_each_tracing_cpu(cpu) { | |
4375 | atomic_dec(&global_trace.data[cpu]->disabled); | |
4376 | } | |
4377 | tracing_on(); | |
4378 | } | |
4379 | ||
3f5a54e3 | 4380 | out: |
cd891ae0 SR |
4381 | __raw_spin_unlock(&ftrace_dump_lock); |
4382 | local_irq_restore(flags); | |
3f5a54e3 SR |
4383 | } |
4384 | ||
cf586b61 FW |
4385 | /* By default: disable tracing after the dump */ |
4386 | void ftrace_dump(void) | |
4387 | { | |
4388 | __ftrace_dump(true); | |
4389 | } | |
4390 | ||
3928a8a2 | 4391 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4392 | { |
73c5162a | 4393 | int ring_buf_size; |
4c11d7ae | 4394 | int i; |
9e01c1b7 | 4395 | int ret = -ENOMEM; |
4c11d7ae | 4396 | |
9e01c1b7 RR |
4397 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4398 | goto out; | |
4399 | ||
4400 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4401 | goto out_free_buffer_mask; | |
4c11d7ae | 4402 | |
b04cc6b1 FW |
4403 | if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) |
4404 | goto out_free_tracing_cpumask; | |
4405 | ||
73c5162a SR |
4406 | /* To save memory, keep the ring buffer size to its minimum */ |
4407 | if (ring_buffer_expanded) | |
4408 | ring_buf_size = trace_buf_size; | |
4409 | else | |
4410 | ring_buf_size = 1; | |
4411 | ||
9e01c1b7 RR |
4412 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4413 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
b04cc6b1 | 4414 | cpumask_clear(tracing_reader_cpumask); |
9e01c1b7 RR |
4415 | |
4416 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
73c5162a | 4417 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4418 | TRACE_BUFFER_FLAGS); |
4419 | if (!global_trace.buffer) { | |
4420 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4421 | WARN_ON(1); | |
9e01c1b7 | 4422 | goto out_free_cpumask; |
4c11d7ae | 4423 | } |
3928a8a2 | 4424 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4425 | |
9e01c1b7 | 4426 | |
4c11d7ae | 4427 | #ifdef CONFIG_TRACER_MAX_TRACE |
73c5162a | 4428 | max_tr.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4429 | TRACE_BUFFER_FLAGS); |
4430 | if (!max_tr.buffer) { | |
4431 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4432 | WARN_ON(1); | |
4433 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4434 | goto out_free_cpumask; |
4c11d7ae | 4435 | } |
3928a8a2 SR |
4436 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
4437 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 4438 | #endif |
ab46428c | 4439 | |
4c11d7ae | 4440 | /* Allocate the first page for all buffers */ |
ab46428c | 4441 | for_each_tracing_cpu(i) { |
566b0aaf | 4442 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 | 4443 | max_tr.data[i] = &per_cpu(max_data, i); |
4c11d7ae | 4444 | } |
bc0c38d1 | 4445 | |
bc0c38d1 SR |
4446 | trace_init_cmdlines(); |
4447 | ||
43a15386 | 4448 | register_tracer(&nop_trace); |
79fb0768 | 4449 | current_trace = &nop_trace; |
b5ad384e FW |
4450 | #ifdef CONFIG_BOOT_TRACER |
4451 | register_tracer(&boot_tracer); | |
b5ad384e | 4452 | #endif |
60a11774 SR |
4453 | /* All seems OK, enable tracing */ |
4454 | tracing_disabled = 0; | |
3928a8a2 | 4455 | |
3f5a54e3 SR |
4456 | atomic_notifier_chain_register(&panic_notifier_list, |
4457 | &trace_panic_notifier); | |
4458 | ||
4459 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4460 | |
4461 | return 0; | |
3f5a54e3 | 4462 | |
9e01c1b7 | 4463 | out_free_cpumask: |
b04cc6b1 FW |
4464 | free_cpumask_var(tracing_reader_cpumask); |
4465 | out_free_tracing_cpumask: | |
9e01c1b7 RR |
4466 | free_cpumask_var(tracing_cpumask); |
4467 | out_free_buffer_mask: | |
4468 | free_cpumask_var(tracing_buffer_mask); | |
4469 | out: | |
4470 | return ret; | |
bc0c38d1 | 4471 | } |
b2821ae6 SR |
4472 | |
4473 | __init static int clear_boot_tracer(void) | |
4474 | { | |
4475 | /* | |
4476 | * The default tracer at boot buffer is an init section. | |
4477 | * This function is called in lateinit. If we did not | |
4478 | * find the boot tracer, then clear it out, to prevent | |
4479 | * later registration from accessing the buffer that is | |
4480 | * about to be freed. | |
4481 | */ | |
4482 | if (!default_bootup_tracer) | |
4483 | return 0; | |
4484 | ||
4485 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4486 | default_bootup_tracer); | |
4487 | default_bootup_tracer = NULL; | |
4488 | ||
4489 | return 0; | |
4490 | } | |
4491 | ||
b5ad384e FW |
4492 | early_initcall(tracer_alloc_buffers); |
4493 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4494 | late_initcall(clear_boot_tracer); |