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Commit | Line | Data |
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16444a8a ACM |
1 | /* |
2 | * Infrastructure for profiling code inserted by 'gcc -pg'. | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2004-2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally ported from the -rt patch by: | |
8 | * Copyright (C) 2007 Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code in the latency_tracer, that is: | |
11 | * | |
12 | * Copyright (C) 2004-2006 Ingo Molnar | |
13 | * Copyright (C) 2004 William Lee Irwin III | |
14 | */ | |
15 | ||
3d083395 SR |
16 | #include <linux/stop_machine.h> |
17 | #include <linux/clocksource.h> | |
18 | #include <linux/kallsyms.h> | |
5072c59f | 19 | #include <linux/seq_file.h> |
4a2b8dda | 20 | #include <linux/suspend.h> |
5072c59f | 21 | #include <linux/debugfs.h> |
3d083395 | 22 | #include <linux/hardirq.h> |
2d8b820b | 23 | #include <linux/kthread.h> |
5072c59f | 24 | #include <linux/uaccess.h> |
f22f9a89 | 25 | #include <linux/kprobes.h> |
2d8b820b | 26 | #include <linux/ftrace.h> |
b0fc494f | 27 | #include <linux/sysctl.h> |
5072c59f | 28 | #include <linux/ctype.h> |
3d083395 | 29 | #include <linux/list.h> |
59df055f | 30 | #include <linux/hash.h> |
3d083395 | 31 | |
8aef2d28 SR |
32 | #include <trace/sched.h> |
33 | ||
395a59d0 AS |
34 | #include <asm/ftrace.h> |
35 | ||
3d083395 | 36 | #include "trace.h" |
bac429f0 | 37 | #include "trace_stat.h" |
16444a8a | 38 | |
6912896e SR |
39 | #define FTRACE_WARN_ON(cond) \ |
40 | do { \ | |
41 | if (WARN_ON(cond)) \ | |
42 | ftrace_kill(); \ | |
43 | } while (0) | |
44 | ||
45 | #define FTRACE_WARN_ON_ONCE(cond) \ | |
46 | do { \ | |
47 | if (WARN_ON_ONCE(cond)) \ | |
48 | ftrace_kill(); \ | |
49 | } while (0) | |
50 | ||
8fc0c701 SR |
51 | /* hash bits for specific function selection */ |
52 | #define FTRACE_HASH_BITS 7 | |
53 | #define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS) | |
54 | ||
4eebcc81 SR |
55 | /* ftrace_enabled is a method to turn ftrace on or off */ |
56 | int ftrace_enabled __read_mostly; | |
d61f82d0 | 57 | static int last_ftrace_enabled; |
b0fc494f | 58 | |
60a7ecf4 SR |
59 | /* Quick disabling of function tracer. */ |
60 | int function_trace_stop; | |
61 | ||
4eebcc81 SR |
62 | /* |
63 | * ftrace_disabled is set when an anomaly is discovered. | |
64 | * ftrace_disabled is much stronger than ftrace_enabled. | |
65 | */ | |
66 | static int ftrace_disabled __read_mostly; | |
67 | ||
52baf119 | 68 | static DEFINE_MUTEX(ftrace_lock); |
b0fc494f | 69 | |
16444a8a ACM |
70 | static struct ftrace_ops ftrace_list_end __read_mostly = |
71 | { | |
72 | .func = ftrace_stub, | |
73 | }; | |
74 | ||
75 | static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end; | |
76 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; | |
60a7ecf4 | 77 | ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub; |
df4fc315 | 78 | ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub; |
16444a8a | 79 | |
f2252935 | 80 | static void ftrace_list_func(unsigned long ip, unsigned long parent_ip) |
16444a8a ACM |
81 | { |
82 | struct ftrace_ops *op = ftrace_list; | |
83 | ||
84 | /* in case someone actually ports this to alpha! */ | |
85 | read_barrier_depends(); | |
86 | ||
87 | while (op != &ftrace_list_end) { | |
88 | /* silly alpha */ | |
89 | read_barrier_depends(); | |
90 | op->func(ip, parent_ip); | |
91 | op = op->next; | |
92 | }; | |
93 | } | |
94 | ||
df4fc315 SR |
95 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip) |
96 | { | |
0ef8cde5 | 97 | if (!test_tsk_trace_trace(current)) |
df4fc315 SR |
98 | return; |
99 | ||
100 | ftrace_pid_function(ip, parent_ip); | |
101 | } | |
102 | ||
103 | static void set_ftrace_pid_function(ftrace_func_t func) | |
104 | { | |
105 | /* do not set ftrace_pid_function to itself! */ | |
106 | if (func != ftrace_pid_func) | |
107 | ftrace_pid_function = func; | |
108 | } | |
109 | ||
16444a8a | 110 | /** |
3d083395 | 111 | * clear_ftrace_function - reset the ftrace function |
16444a8a | 112 | * |
3d083395 SR |
113 | * This NULLs the ftrace function and in essence stops |
114 | * tracing. There may be lag | |
16444a8a | 115 | */ |
3d083395 | 116 | void clear_ftrace_function(void) |
16444a8a | 117 | { |
3d083395 | 118 | ftrace_trace_function = ftrace_stub; |
60a7ecf4 | 119 | __ftrace_trace_function = ftrace_stub; |
df4fc315 | 120 | ftrace_pid_function = ftrace_stub; |
3d083395 SR |
121 | } |
122 | ||
60a7ecf4 SR |
123 | #ifndef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
124 | /* | |
125 | * For those archs that do not test ftrace_trace_stop in their | |
126 | * mcount call site, we need to do it from C. | |
127 | */ | |
128 | static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip) | |
129 | { | |
130 | if (function_trace_stop) | |
131 | return; | |
132 | ||
133 | __ftrace_trace_function(ip, parent_ip); | |
134 | } | |
135 | #endif | |
136 | ||
e309b41d | 137 | static int __register_ftrace_function(struct ftrace_ops *ops) |
3d083395 | 138 | { |
16444a8a ACM |
139 | ops->next = ftrace_list; |
140 | /* | |
141 | * We are entering ops into the ftrace_list but another | |
142 | * CPU might be walking that list. We need to make sure | |
143 | * the ops->next pointer is valid before another CPU sees | |
144 | * the ops pointer included into the ftrace_list. | |
145 | */ | |
146 | smp_wmb(); | |
147 | ftrace_list = ops; | |
3d083395 | 148 | |
b0fc494f | 149 | if (ftrace_enabled) { |
df4fc315 SR |
150 | ftrace_func_t func; |
151 | ||
152 | if (ops->next == &ftrace_list_end) | |
153 | func = ops->func; | |
154 | else | |
155 | func = ftrace_list_func; | |
156 | ||
978f3a45 | 157 | if (ftrace_pid_trace) { |
df4fc315 SR |
158 | set_ftrace_pid_function(func); |
159 | func = ftrace_pid_func; | |
160 | } | |
161 | ||
b0fc494f SR |
162 | /* |
163 | * For one func, simply call it directly. | |
164 | * For more than one func, call the chain. | |
165 | */ | |
60a7ecf4 | 166 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
df4fc315 | 167 | ftrace_trace_function = func; |
60a7ecf4 | 168 | #else |
df4fc315 | 169 | __ftrace_trace_function = func; |
60a7ecf4 SR |
170 | ftrace_trace_function = ftrace_test_stop_func; |
171 | #endif | |
b0fc494f | 172 | } |
3d083395 | 173 | |
16444a8a ACM |
174 | return 0; |
175 | } | |
176 | ||
e309b41d | 177 | static int __unregister_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 178 | { |
16444a8a | 179 | struct ftrace_ops **p; |
16444a8a ACM |
180 | |
181 | /* | |
3d083395 SR |
182 | * If we are removing the last function, then simply point |
183 | * to the ftrace_stub. | |
16444a8a ACM |
184 | */ |
185 | if (ftrace_list == ops && ops->next == &ftrace_list_end) { | |
186 | ftrace_trace_function = ftrace_stub; | |
187 | ftrace_list = &ftrace_list_end; | |
e6ea44e9 | 188 | return 0; |
16444a8a ACM |
189 | } |
190 | ||
191 | for (p = &ftrace_list; *p != &ftrace_list_end; p = &(*p)->next) | |
192 | if (*p == ops) | |
193 | break; | |
194 | ||
e6ea44e9 SR |
195 | if (*p != ops) |
196 | return -1; | |
16444a8a ACM |
197 | |
198 | *p = (*p)->next; | |
199 | ||
b0fc494f SR |
200 | if (ftrace_enabled) { |
201 | /* If we only have one func left, then call that directly */ | |
df4fc315 SR |
202 | if (ftrace_list->next == &ftrace_list_end) { |
203 | ftrace_func_t func = ftrace_list->func; | |
204 | ||
978f3a45 | 205 | if (ftrace_pid_trace) { |
df4fc315 SR |
206 | set_ftrace_pid_function(func); |
207 | func = ftrace_pid_func; | |
208 | } | |
209 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST | |
210 | ftrace_trace_function = func; | |
211 | #else | |
212 | __ftrace_trace_function = func; | |
213 | #endif | |
214 | } | |
b0fc494f | 215 | } |
16444a8a | 216 | |
e6ea44e9 | 217 | return 0; |
3d083395 SR |
218 | } |
219 | ||
df4fc315 SR |
220 | static void ftrace_update_pid_func(void) |
221 | { | |
222 | ftrace_func_t func; | |
223 | ||
df4fc315 | 224 | if (ftrace_trace_function == ftrace_stub) |
10dd3ebe | 225 | return; |
df4fc315 SR |
226 | |
227 | func = ftrace_trace_function; | |
228 | ||
978f3a45 | 229 | if (ftrace_pid_trace) { |
df4fc315 SR |
230 | set_ftrace_pid_function(func); |
231 | func = ftrace_pid_func; | |
232 | } else { | |
66eafebc LW |
233 | if (func == ftrace_pid_func) |
234 | func = ftrace_pid_function; | |
df4fc315 SR |
235 | } |
236 | ||
237 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST | |
238 | ftrace_trace_function = func; | |
239 | #else | |
240 | __ftrace_trace_function = func; | |
241 | #endif | |
df4fc315 SR |
242 | } |
243 | ||
493762fc SR |
244 | #ifdef CONFIG_FUNCTION_PROFILER |
245 | struct ftrace_profile { | |
246 | struct hlist_node node; | |
247 | unsigned long ip; | |
248 | unsigned long counter; | |
8fc0c701 SR |
249 | }; |
250 | ||
493762fc SR |
251 | struct ftrace_profile_page { |
252 | struct ftrace_profile_page *next; | |
253 | unsigned long index; | |
254 | struct ftrace_profile records[]; | |
d61f82d0 SR |
255 | }; |
256 | ||
493762fc SR |
257 | #define PROFILE_RECORDS_SIZE \ |
258 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | |
5072c59f | 259 | |
493762fc SR |
260 | #define PROFILES_PER_PAGE \ |
261 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | |
3d083395 | 262 | |
493762fc SR |
263 | /* TODO: make these percpu, to prevent cache line bouncing */ |
264 | static struct ftrace_profile_page *profile_pages_start; | |
265 | static struct ftrace_profile_page *profile_pages; | |
3c1720f0 | 266 | |
bac429f0 SR |
267 | static struct hlist_head *ftrace_profile_hash; |
268 | static int ftrace_profile_bits; | |
269 | static int ftrace_profile_enabled; | |
270 | static DEFINE_MUTEX(ftrace_profile_lock); | |
271 | ||
493762fc SR |
272 | static DEFINE_PER_CPU(atomic_t, ftrace_profile_disable); |
273 | ||
274 | #define FTRACE_PROFILE_HASH_SIZE 1024 /* must be power of 2 */ | |
275 | ||
276 | static raw_spinlock_t ftrace_profile_rec_lock = | |
277 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
278 | ||
bac429f0 SR |
279 | static void * |
280 | function_stat_next(void *v, int idx) | |
281 | { | |
493762fc SR |
282 | struct ftrace_profile *rec = v; |
283 | struct ftrace_profile_page *pg; | |
bac429f0 | 284 | |
493762fc | 285 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
bac429f0 SR |
286 | |
287 | again: | |
288 | rec++; | |
289 | if ((void *)rec >= (void *)&pg->records[pg->index]) { | |
290 | pg = pg->next; | |
291 | if (!pg) | |
292 | return NULL; | |
293 | rec = &pg->records[0]; | |
493762fc SR |
294 | if (!rec->counter) |
295 | goto again; | |
bac429f0 SR |
296 | } |
297 | ||
bac429f0 SR |
298 | return rec; |
299 | } | |
300 | ||
301 | static void *function_stat_start(struct tracer_stat *trace) | |
302 | { | |
493762fc | 303 | return function_stat_next(&profile_pages_start->records[0], 0); |
bac429f0 SR |
304 | } |
305 | ||
306 | static int function_stat_cmp(void *p1, void *p2) | |
307 | { | |
493762fc SR |
308 | struct ftrace_profile *a = p1; |
309 | struct ftrace_profile *b = p2; | |
bac429f0 SR |
310 | |
311 | if (a->counter < b->counter) | |
312 | return -1; | |
313 | if (a->counter > b->counter) | |
314 | return 1; | |
315 | else | |
316 | return 0; | |
317 | } | |
318 | ||
319 | static int function_stat_headers(struct seq_file *m) | |
320 | { | |
321 | seq_printf(m, " Function Hit\n" | |
322 | " -------- ---\n"); | |
323 | return 0; | |
324 | } | |
325 | ||
326 | static int function_stat_show(struct seq_file *m, void *v) | |
327 | { | |
493762fc | 328 | struct ftrace_profile *rec = v; |
bac429f0 SR |
329 | char str[KSYM_SYMBOL_LEN]; |
330 | ||
331 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
332 | ||
333 | seq_printf(m, " %-30.30s %10lu\n", str, rec->counter); | |
334 | return 0; | |
335 | } | |
336 | ||
337 | static struct tracer_stat function_stats = { | |
338 | .name = "functions", | |
339 | .stat_start = function_stat_start, | |
340 | .stat_next = function_stat_next, | |
341 | .stat_cmp = function_stat_cmp, | |
342 | .stat_headers = function_stat_headers, | |
343 | .stat_show = function_stat_show | |
344 | }; | |
345 | ||
493762fc | 346 | static void ftrace_profile_reset(void) |
bac429f0 | 347 | { |
493762fc | 348 | struct ftrace_profile_page *pg; |
bac429f0 | 349 | |
493762fc | 350 | pg = profile_pages = profile_pages_start; |
bac429f0 | 351 | |
493762fc SR |
352 | while (pg) { |
353 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | |
354 | pg->index = 0; | |
355 | pg = pg->next; | |
bac429f0 SR |
356 | } |
357 | ||
493762fc SR |
358 | memset(ftrace_profile_hash, 0, |
359 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); | |
360 | } | |
bac429f0 | 361 | |
493762fc SR |
362 | int ftrace_profile_pages_init(void) |
363 | { | |
364 | struct ftrace_profile_page *pg; | |
365 | int i; | |
bac429f0 | 366 | |
493762fc SR |
367 | /* If we already allocated, do nothing */ |
368 | if (profile_pages) | |
369 | return 0; | |
bac429f0 | 370 | |
493762fc SR |
371 | profile_pages = (void *)get_zeroed_page(GFP_KERNEL); |
372 | if (!profile_pages) | |
373 | return -ENOMEM; | |
bac429f0 | 374 | |
493762fc | 375 | pg = profile_pages_start = profile_pages; |
bac429f0 | 376 | |
493762fc SR |
377 | /* allocate 10 more pages to start */ |
378 | for (i = 0; i < 10; i++) { | |
379 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); | |
380 | /* | |
381 | * We only care about allocating profile_pages, if | |
382 | * we failed to allocate here, hopefully we will allocate | |
383 | * later. | |
384 | */ | |
385 | if (!pg->next) | |
386 | break; | |
387 | pg = pg->next; | |
388 | } | |
389 | ||
390 | return 0; | |
bac429f0 SR |
391 | } |
392 | ||
493762fc | 393 | static int ftrace_profile_init(void) |
bac429f0 | 394 | { |
493762fc | 395 | int size; |
bac429f0 | 396 | |
493762fc SR |
397 | if (ftrace_profile_hash) { |
398 | /* If the profile is already created, simply reset it */ | |
399 | ftrace_profile_reset(); | |
400 | return 0; | |
401 | } | |
bac429f0 | 402 | |
493762fc SR |
403 | /* |
404 | * We are profiling all functions, but usually only a few thousand | |
405 | * functions are hit. We'll make a hash of 1024 items. | |
406 | */ | |
407 | size = FTRACE_PROFILE_HASH_SIZE; | |
bac429f0 | 408 | |
493762fc SR |
409 | ftrace_profile_hash = |
410 | kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL); | |
411 | ||
412 | if (!ftrace_profile_hash) | |
413 | return -ENOMEM; | |
414 | ||
415 | size--; | |
416 | ||
417 | for (; size; size >>= 1) | |
418 | ftrace_profile_bits++; | |
419 | ||
420 | /* Preallocate a few pages */ | |
421 | if (ftrace_profile_pages_init() < 0) { | |
422 | kfree(ftrace_profile_hash); | |
423 | ftrace_profile_hash = NULL; | |
424 | return -ENOMEM; | |
425 | } | |
426 | ||
427 | return 0; | |
bac429f0 SR |
428 | } |
429 | ||
493762fc SR |
430 | /* interrupts must be disabled */ |
431 | static struct ftrace_profile *ftrace_find_profiled_func(unsigned long ip) | |
bac429f0 | 432 | { |
493762fc | 433 | struct ftrace_profile *rec; |
bac429f0 SR |
434 | struct hlist_head *hhd; |
435 | struct hlist_node *n; | |
bac429f0 SR |
436 | unsigned long key; |
437 | ||
bac429f0 SR |
438 | key = hash_long(ip, ftrace_profile_bits); |
439 | hhd = &ftrace_profile_hash[key]; | |
440 | ||
441 | if (hlist_empty(hhd)) | |
442 | return NULL; | |
443 | ||
bac429f0 SR |
444 | hlist_for_each_entry_rcu(rec, n, hhd, node) { |
445 | if (rec->ip == ip) | |
493762fc SR |
446 | return rec; |
447 | } | |
448 | ||
449 | return NULL; | |
450 | } | |
451 | ||
452 | static void ftrace_add_profile(struct ftrace_profile *rec) | |
453 | { | |
454 | unsigned long key; | |
455 | ||
456 | key = hash_long(rec->ip, ftrace_profile_bits); | |
457 | hlist_add_head_rcu(&rec->node, &ftrace_profile_hash[key]); | |
458 | } | |
459 | ||
460 | /* Interrupts must be disabled calling this */ | |
461 | static struct ftrace_profile * | |
462 | ftrace_profile_alloc(unsigned long ip, bool alloc_safe) | |
463 | { | |
464 | struct ftrace_profile *rec = NULL; | |
465 | ||
466 | /* prevent recursion */ | |
467 | if (atomic_inc_return(&__get_cpu_var(ftrace_profile_disable)) != 1) | |
468 | goto out; | |
469 | ||
470 | __raw_spin_lock(&ftrace_profile_rec_lock); | |
471 | ||
472 | /* Try to always keep another page available */ | |
473 | if (!profile_pages->next && alloc_safe) | |
474 | profile_pages->next = (void *)get_zeroed_page(GFP_ATOMIC); | |
475 | ||
476 | /* | |
477 | * Try to find the function again since another | |
478 | * task on another CPU could have added it | |
479 | */ | |
480 | rec = ftrace_find_profiled_func(ip); | |
481 | if (rec) | |
482 | goto out_unlock; | |
483 | ||
484 | if (profile_pages->index == PROFILES_PER_PAGE) { | |
485 | if (!profile_pages->next) | |
486 | goto out_unlock; | |
487 | profile_pages = profile_pages->next; | |
bac429f0 | 488 | } |
493762fc SR |
489 | |
490 | rec = &profile_pages->records[profile_pages->index++]; | |
491 | rec->ip = ip; | |
492 | ftrace_add_profile(rec); | |
493 | ||
494 | out_unlock: | |
495 | __raw_spin_unlock(&ftrace_profile_rec_lock); | |
bac429f0 | 496 | out: |
493762fc | 497 | atomic_dec(&__get_cpu_var(ftrace_profile_disable)); |
bac429f0 SR |
498 | |
499 | return rec; | |
500 | } | |
501 | ||
493762fc SR |
502 | /* |
503 | * If we are not in an interrupt, or softirq and | |
504 | * and interrupts are disabled and preemption is not enabled | |
505 | * (not in a spinlock) then it should be safe to allocate memory. | |
506 | */ | |
507 | static bool ftrace_safe_to_allocate(void) | |
508 | { | |
509 | return !in_interrupt() && irqs_disabled() && !preempt_count(); | |
510 | } | |
511 | ||
bac429f0 SR |
512 | static void |
513 | function_profile_call(unsigned long ip, unsigned long parent_ip) | |
514 | { | |
493762fc | 515 | struct ftrace_profile *rec; |
bac429f0 | 516 | unsigned long flags; |
493762fc | 517 | bool alloc_safe; |
bac429f0 SR |
518 | |
519 | if (!ftrace_profile_enabled) | |
520 | return; | |
521 | ||
493762fc SR |
522 | alloc_safe = ftrace_safe_to_allocate(); |
523 | ||
bac429f0 SR |
524 | local_irq_save(flags); |
525 | rec = ftrace_find_profiled_func(ip); | |
493762fc SR |
526 | if (!rec) { |
527 | rec = ftrace_profile_alloc(ip, alloc_safe); | |
528 | if (!rec) | |
529 | goto out; | |
530 | } | |
bac429f0 SR |
531 | |
532 | rec->counter++; | |
533 | out: | |
534 | local_irq_restore(flags); | |
535 | } | |
536 | ||
537 | static struct ftrace_ops ftrace_profile_ops __read_mostly = | |
538 | { | |
539 | .func = function_profile_call, | |
540 | }; | |
541 | ||
542 | static ssize_t | |
543 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | |
544 | size_t cnt, loff_t *ppos) | |
545 | { | |
546 | unsigned long val; | |
547 | char buf[64]; | |
548 | int ret; | |
549 | ||
bac429f0 SR |
550 | if (cnt >= sizeof(buf)) |
551 | return -EINVAL; | |
552 | ||
553 | if (copy_from_user(&buf, ubuf, cnt)) | |
554 | return -EFAULT; | |
555 | ||
556 | buf[cnt] = 0; | |
557 | ||
558 | ret = strict_strtoul(buf, 10, &val); | |
559 | if (ret < 0) | |
560 | return ret; | |
561 | ||
562 | val = !!val; | |
563 | ||
564 | mutex_lock(&ftrace_profile_lock); | |
565 | if (ftrace_profile_enabled ^ val) { | |
566 | if (val) { | |
493762fc SR |
567 | ret = ftrace_profile_init(); |
568 | if (ret < 0) { | |
569 | cnt = ret; | |
570 | goto out; | |
571 | } | |
572 | ||
bac429f0 SR |
573 | register_ftrace_function(&ftrace_profile_ops); |
574 | ftrace_profile_enabled = 1; | |
575 | } else { | |
576 | ftrace_profile_enabled = 0; | |
577 | unregister_ftrace_function(&ftrace_profile_ops); | |
578 | } | |
579 | } | |
493762fc | 580 | out: |
bac429f0 SR |
581 | mutex_unlock(&ftrace_profile_lock); |
582 | ||
583 | filp->f_pos += cnt; | |
584 | ||
585 | return cnt; | |
586 | } | |
587 | ||
493762fc SR |
588 | static ssize_t |
589 | ftrace_profile_read(struct file *filp, char __user *ubuf, | |
590 | size_t cnt, loff_t *ppos) | |
591 | { | |
592 | char buf[64]; | |
593 | int r; | |
594 | ||
595 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | |
596 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
597 | } | |
598 | ||
bac429f0 SR |
599 | static const struct file_operations ftrace_profile_fops = { |
600 | .open = tracing_open_generic, | |
601 | .read = ftrace_profile_read, | |
602 | .write = ftrace_profile_write, | |
603 | }; | |
604 | ||
605 | static void ftrace_profile_debugfs(struct dentry *d_tracer) | |
606 | { | |
607 | struct dentry *entry; | |
608 | int ret; | |
609 | ||
610 | ret = register_stat_tracer(&function_stats); | |
611 | if (ret) { | |
612 | pr_warning("Warning: could not register " | |
613 | "function stats\n"); | |
614 | return; | |
615 | } | |
616 | ||
617 | entry = debugfs_create_file("function_profile_enabled", 0644, | |
618 | d_tracer, NULL, &ftrace_profile_fops); | |
619 | if (!entry) | |
620 | pr_warning("Could not create debugfs " | |
621 | "'function_profile_enabled' entry\n"); | |
622 | } | |
623 | ||
bac429f0 | 624 | #else /* CONFIG_FUNCTION_PROFILER */ |
bac429f0 SR |
625 | static void ftrace_profile_debugfs(struct dentry *d_tracer) |
626 | { | |
627 | } | |
bac429f0 SR |
628 | #endif /* CONFIG_FUNCTION_PROFILER */ |
629 | ||
493762fc SR |
630 | /* set when tracing only a pid */ |
631 | struct pid *ftrace_pid_trace; | |
632 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; | |
633 | ||
634 | #ifdef CONFIG_DYNAMIC_FTRACE | |
635 | ||
636 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD | |
637 | # error Dynamic ftrace depends on MCOUNT_RECORD | |
638 | #endif | |
639 | ||
640 | static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly; | |
641 | ||
642 | struct ftrace_func_probe { | |
643 | struct hlist_node node; | |
644 | struct ftrace_probe_ops *ops; | |
645 | unsigned long flags; | |
646 | unsigned long ip; | |
647 | void *data; | |
648 | struct rcu_head rcu; | |
649 | }; | |
650 | ||
651 | enum { | |
652 | FTRACE_ENABLE_CALLS = (1 << 0), | |
653 | FTRACE_DISABLE_CALLS = (1 << 1), | |
654 | FTRACE_UPDATE_TRACE_FUNC = (1 << 2), | |
655 | FTRACE_ENABLE_MCOUNT = (1 << 3), | |
656 | FTRACE_DISABLE_MCOUNT = (1 << 4), | |
657 | FTRACE_START_FUNC_RET = (1 << 5), | |
658 | FTRACE_STOP_FUNC_RET = (1 << 6), | |
659 | }; | |
660 | ||
661 | static int ftrace_filtered; | |
662 | ||
663 | static struct dyn_ftrace *ftrace_new_addrs; | |
664 | ||
665 | static DEFINE_MUTEX(ftrace_regex_lock); | |
666 | ||
667 | struct ftrace_page { | |
668 | struct ftrace_page *next; | |
669 | int index; | |
670 | struct dyn_ftrace records[]; | |
671 | }; | |
672 | ||
673 | #define ENTRIES_PER_PAGE \ | |
674 | ((PAGE_SIZE - sizeof(struct ftrace_page)) / sizeof(struct dyn_ftrace)) | |
675 | ||
676 | /* estimate from running different kernels */ | |
677 | #define NR_TO_INIT 10000 | |
678 | ||
679 | static struct ftrace_page *ftrace_pages_start; | |
680 | static struct ftrace_page *ftrace_pages; | |
681 | ||
682 | static struct dyn_ftrace *ftrace_free_records; | |
683 | ||
684 | /* | |
685 | * This is a double for. Do not use 'break' to break out of the loop, | |
686 | * you must use a goto. | |
687 | */ | |
688 | #define do_for_each_ftrace_rec(pg, rec) \ | |
689 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
690 | int _____i; \ | |
691 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
692 | rec = &pg->records[_____i]; | |
693 | ||
694 | #define while_for_each_ftrace_rec() \ | |
695 | } \ | |
696 | } | |
697 | ||
ecea656d | 698 | #ifdef CONFIG_KPROBES |
f17845e5 IM |
699 | |
700 | static int frozen_record_count; | |
701 | ||
ecea656d AS |
702 | static inline void freeze_record(struct dyn_ftrace *rec) |
703 | { | |
704 | if (!(rec->flags & FTRACE_FL_FROZEN)) { | |
705 | rec->flags |= FTRACE_FL_FROZEN; | |
706 | frozen_record_count++; | |
707 | } | |
708 | } | |
709 | ||
710 | static inline void unfreeze_record(struct dyn_ftrace *rec) | |
711 | { | |
712 | if (rec->flags & FTRACE_FL_FROZEN) { | |
713 | rec->flags &= ~FTRACE_FL_FROZEN; | |
714 | frozen_record_count--; | |
715 | } | |
716 | } | |
717 | ||
718 | static inline int record_frozen(struct dyn_ftrace *rec) | |
719 | { | |
720 | return rec->flags & FTRACE_FL_FROZEN; | |
721 | } | |
722 | #else | |
723 | # define freeze_record(rec) ({ 0; }) | |
724 | # define unfreeze_record(rec) ({ 0; }) | |
725 | # define record_frozen(rec) ({ 0; }) | |
726 | #endif /* CONFIG_KPROBES */ | |
727 | ||
e309b41d | 728 | static void ftrace_free_rec(struct dyn_ftrace *rec) |
37ad5084 | 729 | { |
ee000b7f | 730 | rec->freelist = ftrace_free_records; |
37ad5084 SR |
731 | ftrace_free_records = rec; |
732 | rec->flags |= FTRACE_FL_FREE; | |
733 | } | |
734 | ||
fed1939c SR |
735 | void ftrace_release(void *start, unsigned long size) |
736 | { | |
737 | struct dyn_ftrace *rec; | |
738 | struct ftrace_page *pg; | |
739 | unsigned long s = (unsigned long)start; | |
740 | unsigned long e = s + size; | |
fed1939c | 741 | |
00fd61ae | 742 | if (ftrace_disabled || !start) |
fed1939c SR |
743 | return; |
744 | ||
52baf119 | 745 | mutex_lock(&ftrace_lock); |
265c831c | 746 | do_for_each_ftrace_rec(pg, rec) { |
b00f0b6d | 747 | if ((rec->ip >= s) && (rec->ip < e) && |
493762fc | 748 | !(rec->flags & FTRACE_FL_FREE)) |
265c831c SR |
749 | ftrace_free_rec(rec); |
750 | } while_for_each_ftrace_rec(); | |
52baf119 | 751 | mutex_unlock(&ftrace_lock); |
fed1939c SR |
752 | } |
753 | ||
e309b41d | 754 | static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip) |
3c1720f0 | 755 | { |
37ad5084 SR |
756 | struct dyn_ftrace *rec; |
757 | ||
758 | /* First check for freed records */ | |
759 | if (ftrace_free_records) { | |
760 | rec = ftrace_free_records; | |
761 | ||
37ad5084 | 762 | if (unlikely(!(rec->flags & FTRACE_FL_FREE))) { |
6912896e | 763 | FTRACE_WARN_ON_ONCE(1); |
37ad5084 SR |
764 | ftrace_free_records = NULL; |
765 | return NULL; | |
766 | } | |
767 | ||
ee000b7f | 768 | ftrace_free_records = rec->freelist; |
37ad5084 SR |
769 | memset(rec, 0, sizeof(*rec)); |
770 | return rec; | |
771 | } | |
772 | ||
3c1720f0 | 773 | if (ftrace_pages->index == ENTRIES_PER_PAGE) { |
08f5ac90 SR |
774 | if (!ftrace_pages->next) { |
775 | /* allocate another page */ | |
776 | ftrace_pages->next = | |
777 | (void *)get_zeroed_page(GFP_KERNEL); | |
778 | if (!ftrace_pages->next) | |
779 | return NULL; | |
780 | } | |
3c1720f0 SR |
781 | ftrace_pages = ftrace_pages->next; |
782 | } | |
783 | ||
784 | return &ftrace_pages->records[ftrace_pages->index++]; | |
785 | } | |
786 | ||
08f5ac90 | 787 | static struct dyn_ftrace * |
d61f82d0 | 788 | ftrace_record_ip(unsigned long ip) |
3d083395 | 789 | { |
08f5ac90 | 790 | struct dyn_ftrace *rec; |
3d083395 | 791 | |
f3c7ac40 | 792 | if (ftrace_disabled) |
08f5ac90 | 793 | return NULL; |
3d083395 | 794 | |
08f5ac90 SR |
795 | rec = ftrace_alloc_dyn_node(ip); |
796 | if (!rec) | |
797 | return NULL; | |
3d083395 | 798 | |
08f5ac90 | 799 | rec->ip = ip; |
ee000b7f | 800 | rec->newlist = ftrace_new_addrs; |
e94142a6 | 801 | ftrace_new_addrs = rec; |
3d083395 | 802 | |
08f5ac90 | 803 | return rec; |
3d083395 SR |
804 | } |
805 | ||
b17e8a37 SR |
806 | static void print_ip_ins(const char *fmt, unsigned char *p) |
807 | { | |
808 | int i; | |
809 | ||
810 | printk(KERN_CONT "%s", fmt); | |
811 | ||
812 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
813 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
814 | } | |
815 | ||
31e88909 | 816 | static void ftrace_bug(int failed, unsigned long ip) |
b17e8a37 SR |
817 | { |
818 | switch (failed) { | |
819 | case -EFAULT: | |
820 | FTRACE_WARN_ON_ONCE(1); | |
821 | pr_info("ftrace faulted on modifying "); | |
822 | print_ip_sym(ip); | |
823 | break; | |
824 | case -EINVAL: | |
825 | FTRACE_WARN_ON_ONCE(1); | |
826 | pr_info("ftrace failed to modify "); | |
827 | print_ip_sym(ip); | |
b17e8a37 | 828 | print_ip_ins(" actual: ", (unsigned char *)ip); |
b17e8a37 SR |
829 | printk(KERN_CONT "\n"); |
830 | break; | |
831 | case -EPERM: | |
832 | FTRACE_WARN_ON_ONCE(1); | |
833 | pr_info("ftrace faulted on writing "); | |
834 | print_ip_sym(ip); | |
835 | break; | |
836 | default: | |
837 | FTRACE_WARN_ON_ONCE(1); | |
838 | pr_info("ftrace faulted on unknown error "); | |
839 | print_ip_sym(ip); | |
840 | } | |
841 | } | |
842 | ||
3c1720f0 | 843 | |
0eb96701 | 844 | static int |
31e88909 | 845 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) |
5072c59f | 846 | { |
e7d3737e | 847 | unsigned long ftrace_addr; |
6a24a244 | 848 | unsigned long ip, fl; |
e7d3737e | 849 | |
f0001207 | 850 | ftrace_addr = (unsigned long)FTRACE_ADDR; |
5072c59f SR |
851 | |
852 | ip = rec->ip; | |
853 | ||
982c350b SR |
854 | /* |
855 | * If this record is not to be traced and | |
856 | * it is not enabled then do nothing. | |
857 | * | |
858 | * If this record is not to be traced and | |
57794a9d | 859 | * it is enabled then disable it. |
982c350b SR |
860 | * |
861 | */ | |
862 | if (rec->flags & FTRACE_FL_NOTRACE) { | |
863 | if (rec->flags & FTRACE_FL_ENABLED) | |
864 | rec->flags &= ~FTRACE_FL_ENABLED; | |
865 | else | |
866 | return 0; | |
867 | ||
868 | } else if (ftrace_filtered && enable) { | |
5072c59f | 869 | /* |
982c350b | 870 | * Filtering is on: |
5072c59f | 871 | */ |
a4500b84 | 872 | |
982c350b | 873 | fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED); |
5072c59f | 874 | |
982c350b SR |
875 | /* Record is filtered and enabled, do nothing */ |
876 | if (fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED)) | |
0eb96701 | 877 | return 0; |
5072c59f | 878 | |
57794a9d | 879 | /* Record is not filtered or enabled, do nothing */ |
982c350b SR |
880 | if (!fl) |
881 | return 0; | |
882 | ||
883 | /* Record is not filtered but enabled, disable it */ | |
884 | if (fl == FTRACE_FL_ENABLED) | |
5072c59f | 885 | rec->flags &= ~FTRACE_FL_ENABLED; |
982c350b SR |
886 | else |
887 | /* Otherwise record is filtered but not enabled, enable it */ | |
5072c59f | 888 | rec->flags |= FTRACE_FL_ENABLED; |
5072c59f | 889 | } else { |
982c350b | 890 | /* Disable or not filtered */ |
5072c59f | 891 | |
41c52c0d | 892 | if (enable) { |
982c350b | 893 | /* if record is enabled, do nothing */ |
5072c59f | 894 | if (rec->flags & FTRACE_FL_ENABLED) |
0eb96701 | 895 | return 0; |
982c350b | 896 | |
5072c59f | 897 | rec->flags |= FTRACE_FL_ENABLED; |
982c350b | 898 | |
5072c59f | 899 | } else { |
982c350b | 900 | |
57794a9d | 901 | /* if record is not enabled, do nothing */ |
5072c59f | 902 | if (!(rec->flags & FTRACE_FL_ENABLED)) |
0eb96701 | 903 | return 0; |
982c350b | 904 | |
5072c59f SR |
905 | rec->flags &= ~FTRACE_FL_ENABLED; |
906 | } | |
907 | } | |
908 | ||
982c350b | 909 | if (rec->flags & FTRACE_FL_ENABLED) |
e7d3737e | 910 | return ftrace_make_call(rec, ftrace_addr); |
31e88909 | 911 | else |
e7d3737e | 912 | return ftrace_make_nop(NULL, rec, ftrace_addr); |
5072c59f SR |
913 | } |
914 | ||
e309b41d | 915 | static void ftrace_replace_code(int enable) |
3c1720f0 | 916 | { |
3c1720f0 SR |
917 | struct dyn_ftrace *rec; |
918 | struct ftrace_page *pg; | |
6a24a244 | 919 | int failed; |
3c1720f0 | 920 | |
265c831c SR |
921 | do_for_each_ftrace_rec(pg, rec) { |
922 | /* | |
fa9d13cf Z |
923 | * Skip over free records, records that have |
924 | * failed and not converted. | |
265c831c SR |
925 | */ |
926 | if (rec->flags & FTRACE_FL_FREE || | |
fa9d13cf | 927 | rec->flags & FTRACE_FL_FAILED || |
03303549 | 928 | !(rec->flags & FTRACE_FL_CONVERTED)) |
265c831c SR |
929 | continue; |
930 | ||
931 | /* ignore updates to this record's mcount site */ | |
932 | if (get_kprobe((void *)rec->ip)) { | |
933 | freeze_record(rec); | |
934 | continue; | |
935 | } else { | |
936 | unfreeze_record(rec); | |
937 | } | |
f22f9a89 | 938 | |
265c831c | 939 | failed = __ftrace_replace_code(rec, enable); |
fa9d13cf | 940 | if (failed) { |
265c831c SR |
941 | rec->flags |= FTRACE_FL_FAILED; |
942 | if ((system_state == SYSTEM_BOOTING) || | |
943 | !core_kernel_text(rec->ip)) { | |
944 | ftrace_free_rec(rec); | |
4377245a | 945 | } else { |
265c831c | 946 | ftrace_bug(failed, rec->ip); |
4377245a SR |
947 | /* Stop processing */ |
948 | return; | |
949 | } | |
3c1720f0 | 950 | } |
265c831c | 951 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
952 | } |
953 | ||
492a7ea5 | 954 | static int |
31e88909 | 955 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 SR |
956 | { |
957 | unsigned long ip; | |
593eb8a2 | 958 | int ret; |
3c1720f0 SR |
959 | |
960 | ip = rec->ip; | |
961 | ||
25aac9dc | 962 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
593eb8a2 | 963 | if (ret) { |
31e88909 | 964 | ftrace_bug(ret, ip); |
3c1720f0 | 965 | rec->flags |= FTRACE_FL_FAILED; |
492a7ea5 | 966 | return 0; |
37ad5084 | 967 | } |
492a7ea5 | 968 | return 1; |
3c1720f0 SR |
969 | } |
970 | ||
000ab691 SR |
971 | /* |
972 | * archs can override this function if they must do something | |
973 | * before the modifying code is performed. | |
974 | */ | |
975 | int __weak ftrace_arch_code_modify_prepare(void) | |
976 | { | |
977 | return 0; | |
978 | } | |
979 | ||
980 | /* | |
981 | * archs can override this function if they must do something | |
982 | * after the modifying code is performed. | |
983 | */ | |
984 | int __weak ftrace_arch_code_modify_post_process(void) | |
985 | { | |
986 | return 0; | |
987 | } | |
988 | ||
e309b41d | 989 | static int __ftrace_modify_code(void *data) |
3d083395 | 990 | { |
d61f82d0 SR |
991 | int *command = data; |
992 | ||
a3583244 | 993 | if (*command & FTRACE_ENABLE_CALLS) |
d61f82d0 | 994 | ftrace_replace_code(1); |
a3583244 | 995 | else if (*command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
996 | ftrace_replace_code(0); |
997 | ||
998 | if (*command & FTRACE_UPDATE_TRACE_FUNC) | |
999 | ftrace_update_ftrace_func(ftrace_trace_function); | |
1000 | ||
5a45cfe1 SR |
1001 | if (*command & FTRACE_START_FUNC_RET) |
1002 | ftrace_enable_ftrace_graph_caller(); | |
1003 | else if (*command & FTRACE_STOP_FUNC_RET) | |
1004 | ftrace_disable_ftrace_graph_caller(); | |
1005 | ||
d61f82d0 | 1006 | return 0; |
3d083395 SR |
1007 | } |
1008 | ||
e309b41d | 1009 | static void ftrace_run_update_code(int command) |
3d083395 | 1010 | { |
000ab691 SR |
1011 | int ret; |
1012 | ||
1013 | ret = ftrace_arch_code_modify_prepare(); | |
1014 | FTRACE_WARN_ON(ret); | |
1015 | if (ret) | |
1016 | return; | |
1017 | ||
784e2d76 | 1018 | stop_machine(__ftrace_modify_code, &command, NULL); |
000ab691 SR |
1019 | |
1020 | ret = ftrace_arch_code_modify_post_process(); | |
1021 | FTRACE_WARN_ON(ret); | |
3d083395 SR |
1022 | } |
1023 | ||
d61f82d0 | 1024 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 1025 | static int ftrace_start_up; |
df4fc315 SR |
1026 | |
1027 | static void ftrace_startup_enable(int command) | |
1028 | { | |
1029 | if (saved_ftrace_func != ftrace_trace_function) { | |
1030 | saved_ftrace_func = ftrace_trace_function; | |
1031 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
1032 | } | |
1033 | ||
1034 | if (!command || !ftrace_enabled) | |
1035 | return; | |
1036 | ||
1037 | ftrace_run_update_code(command); | |
1038 | } | |
d61f82d0 | 1039 | |
5a45cfe1 | 1040 | static void ftrace_startup(int command) |
3d083395 | 1041 | { |
4eebcc81 SR |
1042 | if (unlikely(ftrace_disabled)) |
1043 | return; | |
1044 | ||
60a7ecf4 | 1045 | ftrace_start_up++; |
982c350b | 1046 | command |= FTRACE_ENABLE_CALLS; |
d61f82d0 | 1047 | |
df4fc315 | 1048 | ftrace_startup_enable(command); |
3d083395 SR |
1049 | } |
1050 | ||
5a45cfe1 | 1051 | static void ftrace_shutdown(int command) |
3d083395 | 1052 | { |
4eebcc81 SR |
1053 | if (unlikely(ftrace_disabled)) |
1054 | return; | |
1055 | ||
60a7ecf4 SR |
1056 | ftrace_start_up--; |
1057 | if (!ftrace_start_up) | |
d61f82d0 | 1058 | command |= FTRACE_DISABLE_CALLS; |
3d083395 | 1059 | |
d61f82d0 SR |
1060 | if (saved_ftrace_func != ftrace_trace_function) { |
1061 | saved_ftrace_func = ftrace_trace_function; | |
1062 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
1063 | } | |
3d083395 | 1064 | |
d61f82d0 | 1065 | if (!command || !ftrace_enabled) |
e6ea44e9 | 1066 | return; |
d61f82d0 SR |
1067 | |
1068 | ftrace_run_update_code(command); | |
3d083395 SR |
1069 | } |
1070 | ||
e309b41d | 1071 | static void ftrace_startup_sysctl(void) |
b0fc494f | 1072 | { |
d61f82d0 SR |
1073 | int command = FTRACE_ENABLE_MCOUNT; |
1074 | ||
4eebcc81 SR |
1075 | if (unlikely(ftrace_disabled)) |
1076 | return; | |
1077 | ||
d61f82d0 SR |
1078 | /* Force update next time */ |
1079 | saved_ftrace_func = NULL; | |
60a7ecf4 SR |
1080 | /* ftrace_start_up is true if we want ftrace running */ |
1081 | if (ftrace_start_up) | |
d61f82d0 SR |
1082 | command |= FTRACE_ENABLE_CALLS; |
1083 | ||
1084 | ftrace_run_update_code(command); | |
b0fc494f SR |
1085 | } |
1086 | ||
e309b41d | 1087 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 1088 | { |
d61f82d0 SR |
1089 | int command = FTRACE_DISABLE_MCOUNT; |
1090 | ||
4eebcc81 SR |
1091 | if (unlikely(ftrace_disabled)) |
1092 | return; | |
1093 | ||
60a7ecf4 SR |
1094 | /* ftrace_start_up is true if ftrace is running */ |
1095 | if (ftrace_start_up) | |
d61f82d0 SR |
1096 | command |= FTRACE_DISABLE_CALLS; |
1097 | ||
1098 | ftrace_run_update_code(command); | |
b0fc494f SR |
1099 | } |
1100 | ||
3d083395 SR |
1101 | static cycle_t ftrace_update_time; |
1102 | static unsigned long ftrace_update_cnt; | |
1103 | unsigned long ftrace_update_tot_cnt; | |
1104 | ||
31e88909 | 1105 | static int ftrace_update_code(struct module *mod) |
3d083395 | 1106 | { |
e94142a6 | 1107 | struct dyn_ftrace *p; |
f22f9a89 | 1108 | cycle_t start, stop; |
3d083395 | 1109 | |
750ed1a4 | 1110 | start = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
1111 | ftrace_update_cnt = 0; |
1112 | ||
e94142a6 | 1113 | while (ftrace_new_addrs) { |
3d083395 | 1114 | |
08f5ac90 SR |
1115 | /* If something went wrong, bail without enabling anything */ |
1116 | if (unlikely(ftrace_disabled)) | |
1117 | return -1; | |
f22f9a89 | 1118 | |
e94142a6 | 1119 | p = ftrace_new_addrs; |
ee000b7f | 1120 | ftrace_new_addrs = p->newlist; |
e94142a6 | 1121 | p->flags = 0L; |
f22f9a89 | 1122 | |
08f5ac90 | 1123 | /* convert record (i.e, patch mcount-call with NOP) */ |
31e88909 | 1124 | if (ftrace_code_disable(mod, p)) { |
08f5ac90 SR |
1125 | p->flags |= FTRACE_FL_CONVERTED; |
1126 | ftrace_update_cnt++; | |
1127 | } else | |
1128 | ftrace_free_rec(p); | |
3d083395 SR |
1129 | } |
1130 | ||
750ed1a4 | 1131 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
1132 | ftrace_update_time = stop - start; |
1133 | ftrace_update_tot_cnt += ftrace_update_cnt; | |
1134 | ||
16444a8a ACM |
1135 | return 0; |
1136 | } | |
1137 | ||
68bf21aa | 1138 | static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) |
3c1720f0 SR |
1139 | { |
1140 | struct ftrace_page *pg; | |
1141 | int cnt; | |
1142 | int i; | |
3c1720f0 SR |
1143 | |
1144 | /* allocate a few pages */ | |
1145 | ftrace_pages_start = (void *)get_zeroed_page(GFP_KERNEL); | |
1146 | if (!ftrace_pages_start) | |
1147 | return -1; | |
1148 | ||
1149 | /* | |
1150 | * Allocate a few more pages. | |
1151 | * | |
1152 | * TODO: have some parser search vmlinux before | |
1153 | * final linking to find all calls to ftrace. | |
1154 | * Then we can: | |
1155 | * a) know how many pages to allocate. | |
1156 | * and/or | |
1157 | * b) set up the table then. | |
1158 | * | |
1159 | * The dynamic code is still necessary for | |
1160 | * modules. | |
1161 | */ | |
1162 | ||
1163 | pg = ftrace_pages = ftrace_pages_start; | |
1164 | ||
68bf21aa | 1165 | cnt = num_to_init / ENTRIES_PER_PAGE; |
08f5ac90 | 1166 | pr_info("ftrace: allocating %ld entries in %d pages\n", |
5821e1b7 | 1167 | num_to_init, cnt + 1); |
3c1720f0 SR |
1168 | |
1169 | for (i = 0; i < cnt; i++) { | |
1170 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); | |
1171 | ||
1172 | /* If we fail, we'll try later anyway */ | |
1173 | if (!pg->next) | |
1174 | break; | |
1175 | ||
1176 | pg = pg->next; | |
1177 | } | |
1178 | ||
1179 | return 0; | |
1180 | } | |
1181 | ||
5072c59f SR |
1182 | enum { |
1183 | FTRACE_ITER_FILTER = (1 << 0), | |
1184 | FTRACE_ITER_CONT = (1 << 1), | |
41c52c0d | 1185 | FTRACE_ITER_NOTRACE = (1 << 2), |
eb9a7bf0 | 1186 | FTRACE_ITER_FAILURES = (1 << 3), |
0c75a3ed | 1187 | FTRACE_ITER_PRINTALL = (1 << 4), |
8fc0c701 | 1188 | FTRACE_ITER_HASH = (1 << 5), |
5072c59f SR |
1189 | }; |
1190 | ||
1191 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ | |
1192 | ||
1193 | struct ftrace_iterator { | |
5072c59f | 1194 | struct ftrace_page *pg; |
8fc0c701 | 1195 | int hidx; |
431aa3fb | 1196 | int idx; |
5072c59f SR |
1197 | unsigned flags; |
1198 | unsigned char buffer[FTRACE_BUFF_MAX+1]; | |
1199 | unsigned buffer_idx; | |
1200 | unsigned filtered; | |
1201 | }; | |
1202 | ||
8fc0c701 SR |
1203 | static void * |
1204 | t_hash_next(struct seq_file *m, void *v, loff_t *pos) | |
1205 | { | |
1206 | struct ftrace_iterator *iter = m->private; | |
1207 | struct hlist_node *hnd = v; | |
1208 | struct hlist_head *hhd; | |
1209 | ||
1210 | WARN_ON(!(iter->flags & FTRACE_ITER_HASH)); | |
1211 | ||
1212 | (*pos)++; | |
1213 | ||
1214 | retry: | |
1215 | if (iter->hidx >= FTRACE_FUNC_HASHSIZE) | |
1216 | return NULL; | |
1217 | ||
1218 | hhd = &ftrace_func_hash[iter->hidx]; | |
1219 | ||
1220 | if (hlist_empty(hhd)) { | |
1221 | iter->hidx++; | |
1222 | hnd = NULL; | |
1223 | goto retry; | |
1224 | } | |
1225 | ||
1226 | if (!hnd) | |
1227 | hnd = hhd->first; | |
1228 | else { | |
1229 | hnd = hnd->next; | |
1230 | if (!hnd) { | |
1231 | iter->hidx++; | |
1232 | goto retry; | |
1233 | } | |
1234 | } | |
1235 | ||
1236 | return hnd; | |
1237 | } | |
1238 | ||
1239 | static void *t_hash_start(struct seq_file *m, loff_t *pos) | |
1240 | { | |
1241 | struct ftrace_iterator *iter = m->private; | |
1242 | void *p = NULL; | |
1243 | ||
1244 | iter->flags |= FTRACE_ITER_HASH; | |
1245 | ||
1246 | return t_hash_next(m, p, pos); | |
1247 | } | |
1248 | ||
1249 | static int t_hash_show(struct seq_file *m, void *v) | |
1250 | { | |
b6887d79 | 1251 | struct ftrace_func_probe *rec; |
8fc0c701 SR |
1252 | struct hlist_node *hnd = v; |
1253 | char str[KSYM_SYMBOL_LEN]; | |
1254 | ||
b6887d79 | 1255 | rec = hlist_entry(hnd, struct ftrace_func_probe, node); |
8fc0c701 | 1256 | |
809dcf29 SR |
1257 | if (rec->ops->print) |
1258 | return rec->ops->print(m, rec->ip, rec->ops, rec->data); | |
1259 | ||
8fc0c701 SR |
1260 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); |
1261 | seq_printf(m, "%s:", str); | |
1262 | ||
1263 | kallsyms_lookup((unsigned long)rec->ops->func, NULL, NULL, NULL, str); | |
1264 | seq_printf(m, "%s", str); | |
1265 | ||
1266 | if (rec->data) | |
1267 | seq_printf(m, ":%p", rec->data); | |
1268 | seq_putc(m, '\n'); | |
1269 | ||
1270 | return 0; | |
1271 | } | |
1272 | ||
e309b41d | 1273 | static void * |
5072c59f SR |
1274 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1275 | { | |
1276 | struct ftrace_iterator *iter = m->private; | |
1277 | struct dyn_ftrace *rec = NULL; | |
1278 | ||
8fc0c701 SR |
1279 | if (iter->flags & FTRACE_ITER_HASH) |
1280 | return t_hash_next(m, v, pos); | |
1281 | ||
5072c59f SR |
1282 | (*pos)++; |
1283 | ||
0c75a3ed SR |
1284 | if (iter->flags & FTRACE_ITER_PRINTALL) |
1285 | return NULL; | |
1286 | ||
5072c59f SR |
1287 | retry: |
1288 | if (iter->idx >= iter->pg->index) { | |
1289 | if (iter->pg->next) { | |
1290 | iter->pg = iter->pg->next; | |
1291 | iter->idx = 0; | |
1292 | goto retry; | |
50cdaf08 LW |
1293 | } else { |
1294 | iter->idx = -1; | |
5072c59f SR |
1295 | } |
1296 | } else { | |
1297 | rec = &iter->pg->records[iter->idx++]; | |
a9fdda33 SR |
1298 | if ((rec->flags & FTRACE_FL_FREE) || |
1299 | ||
1300 | (!(iter->flags & FTRACE_ITER_FAILURES) && | |
eb9a7bf0 AS |
1301 | (rec->flags & FTRACE_FL_FAILED)) || |
1302 | ||
1303 | ((iter->flags & FTRACE_ITER_FAILURES) && | |
a9fdda33 | 1304 | !(rec->flags & FTRACE_FL_FAILED)) || |
eb9a7bf0 | 1305 | |
0183fb1c SR |
1306 | ((iter->flags & FTRACE_ITER_FILTER) && |
1307 | !(rec->flags & FTRACE_FL_FILTER)) || | |
1308 | ||
41c52c0d SR |
1309 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
1310 | !(rec->flags & FTRACE_FL_NOTRACE))) { | |
5072c59f SR |
1311 | rec = NULL; |
1312 | goto retry; | |
1313 | } | |
1314 | } | |
1315 | ||
5072c59f SR |
1316 | return rec; |
1317 | } | |
1318 | ||
1319 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1320 | { | |
1321 | struct ftrace_iterator *iter = m->private; | |
1322 | void *p = NULL; | |
5072c59f | 1323 | |
8fc0c701 | 1324 | mutex_lock(&ftrace_lock); |
0c75a3ed SR |
1325 | /* |
1326 | * For set_ftrace_filter reading, if we have the filter | |
1327 | * off, we can short cut and just print out that all | |
1328 | * functions are enabled. | |
1329 | */ | |
1330 | if (iter->flags & FTRACE_ITER_FILTER && !ftrace_filtered) { | |
1331 | if (*pos > 0) | |
8fc0c701 | 1332 | return t_hash_start(m, pos); |
0c75a3ed SR |
1333 | iter->flags |= FTRACE_ITER_PRINTALL; |
1334 | (*pos)++; | |
1335 | return iter; | |
1336 | } | |
1337 | ||
8fc0c701 SR |
1338 | if (iter->flags & FTRACE_ITER_HASH) |
1339 | return t_hash_start(m, pos); | |
1340 | ||
50cdaf08 LW |
1341 | if (*pos > 0) { |
1342 | if (iter->idx < 0) | |
1343 | return p; | |
1344 | (*pos)--; | |
1345 | iter->idx--; | |
1346 | } | |
5821e1b7 | 1347 | |
50cdaf08 | 1348 | p = t_next(m, p, pos); |
5072c59f | 1349 | |
8fc0c701 SR |
1350 | if (!p) |
1351 | return t_hash_start(m, pos); | |
1352 | ||
5072c59f SR |
1353 | return p; |
1354 | } | |
1355 | ||
1356 | static void t_stop(struct seq_file *m, void *p) | |
1357 | { | |
8fc0c701 | 1358 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
1359 | } |
1360 | ||
1361 | static int t_show(struct seq_file *m, void *v) | |
1362 | { | |
0c75a3ed | 1363 | struct ftrace_iterator *iter = m->private; |
5072c59f SR |
1364 | struct dyn_ftrace *rec = v; |
1365 | char str[KSYM_SYMBOL_LEN]; | |
1366 | ||
8fc0c701 SR |
1367 | if (iter->flags & FTRACE_ITER_HASH) |
1368 | return t_hash_show(m, v); | |
1369 | ||
0c75a3ed SR |
1370 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
1371 | seq_printf(m, "#### all functions enabled ####\n"); | |
1372 | return 0; | |
1373 | } | |
1374 | ||
5072c59f SR |
1375 | if (!rec) |
1376 | return 0; | |
1377 | ||
1378 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
1379 | ||
50cdaf08 | 1380 | seq_printf(m, "%s\n", str); |
5072c59f SR |
1381 | |
1382 | return 0; | |
1383 | } | |
1384 | ||
1385 | static struct seq_operations show_ftrace_seq_ops = { | |
1386 | .start = t_start, | |
1387 | .next = t_next, | |
1388 | .stop = t_stop, | |
1389 | .show = t_show, | |
1390 | }; | |
1391 | ||
e309b41d | 1392 | static int |
5072c59f SR |
1393 | ftrace_avail_open(struct inode *inode, struct file *file) |
1394 | { | |
1395 | struct ftrace_iterator *iter; | |
1396 | int ret; | |
1397 | ||
4eebcc81 SR |
1398 | if (unlikely(ftrace_disabled)) |
1399 | return -ENODEV; | |
1400 | ||
5072c59f SR |
1401 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
1402 | if (!iter) | |
1403 | return -ENOMEM; | |
1404 | ||
1405 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
1406 | |
1407 | ret = seq_open(file, &show_ftrace_seq_ops); | |
1408 | if (!ret) { | |
1409 | struct seq_file *m = file->private_data; | |
4bf39a94 | 1410 | |
5072c59f | 1411 | m->private = iter; |
4bf39a94 | 1412 | } else { |
5072c59f | 1413 | kfree(iter); |
4bf39a94 | 1414 | } |
5072c59f SR |
1415 | |
1416 | return ret; | |
1417 | } | |
1418 | ||
1419 | int ftrace_avail_release(struct inode *inode, struct file *file) | |
1420 | { | |
1421 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1422 | struct ftrace_iterator *iter = m->private; | |
1423 | ||
1424 | seq_release(inode, file); | |
1425 | kfree(iter); | |
4bf39a94 | 1426 | |
5072c59f SR |
1427 | return 0; |
1428 | } | |
1429 | ||
eb9a7bf0 AS |
1430 | static int |
1431 | ftrace_failures_open(struct inode *inode, struct file *file) | |
1432 | { | |
1433 | int ret; | |
1434 | struct seq_file *m; | |
1435 | struct ftrace_iterator *iter; | |
1436 | ||
1437 | ret = ftrace_avail_open(inode, file); | |
1438 | if (!ret) { | |
1439 | m = (struct seq_file *)file->private_data; | |
1440 | iter = (struct ftrace_iterator *)m->private; | |
1441 | iter->flags = FTRACE_ITER_FAILURES; | |
1442 | } | |
1443 | ||
1444 | return ret; | |
1445 | } | |
1446 | ||
1447 | ||
41c52c0d | 1448 | static void ftrace_filter_reset(int enable) |
5072c59f SR |
1449 | { |
1450 | struct ftrace_page *pg; | |
1451 | struct dyn_ftrace *rec; | |
41c52c0d | 1452 | unsigned long type = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
5072c59f | 1453 | |
52baf119 | 1454 | mutex_lock(&ftrace_lock); |
41c52c0d SR |
1455 | if (enable) |
1456 | ftrace_filtered = 0; | |
265c831c SR |
1457 | do_for_each_ftrace_rec(pg, rec) { |
1458 | if (rec->flags & FTRACE_FL_FAILED) | |
1459 | continue; | |
1460 | rec->flags &= ~type; | |
1461 | } while_for_each_ftrace_rec(); | |
52baf119 | 1462 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
1463 | } |
1464 | ||
e309b41d | 1465 | static int |
41c52c0d | 1466 | ftrace_regex_open(struct inode *inode, struct file *file, int enable) |
5072c59f SR |
1467 | { |
1468 | struct ftrace_iterator *iter; | |
1469 | int ret = 0; | |
1470 | ||
4eebcc81 SR |
1471 | if (unlikely(ftrace_disabled)) |
1472 | return -ENODEV; | |
1473 | ||
5072c59f SR |
1474 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
1475 | if (!iter) | |
1476 | return -ENOMEM; | |
1477 | ||
41c52c0d | 1478 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
1479 | if ((file->f_mode & FMODE_WRITE) && |
1480 | !(file->f_flags & O_APPEND)) | |
41c52c0d | 1481 | ftrace_filter_reset(enable); |
5072c59f SR |
1482 | |
1483 | if (file->f_mode & FMODE_READ) { | |
1484 | iter->pg = ftrace_pages_start; | |
41c52c0d SR |
1485 | iter->flags = enable ? FTRACE_ITER_FILTER : |
1486 | FTRACE_ITER_NOTRACE; | |
5072c59f SR |
1487 | |
1488 | ret = seq_open(file, &show_ftrace_seq_ops); | |
1489 | if (!ret) { | |
1490 | struct seq_file *m = file->private_data; | |
1491 | m->private = iter; | |
1492 | } else | |
1493 | kfree(iter); | |
1494 | } else | |
1495 | file->private_data = iter; | |
41c52c0d | 1496 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
1497 | |
1498 | return ret; | |
1499 | } | |
1500 | ||
41c52c0d SR |
1501 | static int |
1502 | ftrace_filter_open(struct inode *inode, struct file *file) | |
1503 | { | |
1504 | return ftrace_regex_open(inode, file, 1); | |
1505 | } | |
1506 | ||
1507 | static int | |
1508 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
1509 | { | |
1510 | return ftrace_regex_open(inode, file, 0); | |
1511 | } | |
1512 | ||
e309b41d | 1513 | static loff_t |
41c52c0d | 1514 | ftrace_regex_lseek(struct file *file, loff_t offset, int origin) |
5072c59f SR |
1515 | { |
1516 | loff_t ret; | |
1517 | ||
1518 | if (file->f_mode & FMODE_READ) | |
1519 | ret = seq_lseek(file, offset, origin); | |
1520 | else | |
1521 | file->f_pos = ret = 1; | |
1522 | ||
1523 | return ret; | |
1524 | } | |
1525 | ||
1526 | enum { | |
1527 | MATCH_FULL, | |
1528 | MATCH_FRONT_ONLY, | |
1529 | MATCH_MIDDLE_ONLY, | |
1530 | MATCH_END_ONLY, | |
1531 | }; | |
1532 | ||
9f4801e3 SR |
1533 | /* |
1534 | * (static function - no need for kernel doc) | |
1535 | * | |
1536 | * Pass in a buffer containing a glob and this function will | |
1537 | * set search to point to the search part of the buffer and | |
1538 | * return the type of search it is (see enum above). | |
1539 | * This does modify buff. | |
1540 | * | |
1541 | * Returns enum type. | |
1542 | * search returns the pointer to use for comparison. | |
1543 | * not returns 1 if buff started with a '!' | |
1544 | * 0 otherwise. | |
1545 | */ | |
1546 | static int | |
64e7c440 | 1547 | ftrace_setup_glob(char *buff, int len, char **search, int *not) |
5072c59f | 1548 | { |
5072c59f | 1549 | int type = MATCH_FULL; |
9f4801e3 | 1550 | int i; |
ea3a6d6d SR |
1551 | |
1552 | if (buff[0] == '!') { | |
9f4801e3 | 1553 | *not = 1; |
ea3a6d6d SR |
1554 | buff++; |
1555 | len--; | |
9f4801e3 SR |
1556 | } else |
1557 | *not = 0; | |
1558 | ||
1559 | *search = buff; | |
5072c59f SR |
1560 | |
1561 | for (i = 0; i < len; i++) { | |
1562 | if (buff[i] == '*') { | |
1563 | if (!i) { | |
9f4801e3 | 1564 | *search = buff + 1; |
5072c59f | 1565 | type = MATCH_END_ONLY; |
5072c59f | 1566 | } else { |
9f4801e3 | 1567 | if (type == MATCH_END_ONLY) |
5072c59f | 1568 | type = MATCH_MIDDLE_ONLY; |
9f4801e3 | 1569 | else |
5072c59f | 1570 | type = MATCH_FRONT_ONLY; |
5072c59f SR |
1571 | buff[i] = 0; |
1572 | break; | |
1573 | } | |
1574 | } | |
1575 | } | |
1576 | ||
9f4801e3 SR |
1577 | return type; |
1578 | } | |
1579 | ||
64e7c440 | 1580 | static int ftrace_match(char *str, char *regex, int len, int type) |
9f4801e3 | 1581 | { |
9f4801e3 SR |
1582 | int matched = 0; |
1583 | char *ptr; | |
1584 | ||
9f4801e3 SR |
1585 | switch (type) { |
1586 | case MATCH_FULL: | |
1587 | if (strcmp(str, regex) == 0) | |
1588 | matched = 1; | |
1589 | break; | |
1590 | case MATCH_FRONT_ONLY: | |
1591 | if (strncmp(str, regex, len) == 0) | |
1592 | matched = 1; | |
1593 | break; | |
1594 | case MATCH_MIDDLE_ONLY: | |
1595 | if (strstr(str, regex)) | |
1596 | matched = 1; | |
1597 | break; | |
1598 | case MATCH_END_ONLY: | |
1599 | ptr = strstr(str, regex); | |
1600 | if (ptr && (ptr[len] == 0)) | |
1601 | matched = 1; | |
1602 | break; | |
1603 | } | |
1604 | ||
1605 | return matched; | |
1606 | } | |
1607 | ||
64e7c440 SR |
1608 | static int |
1609 | ftrace_match_record(struct dyn_ftrace *rec, char *regex, int len, int type) | |
1610 | { | |
1611 | char str[KSYM_SYMBOL_LEN]; | |
1612 | ||
1613 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
1614 | return ftrace_match(str, regex, len, type); | |
1615 | } | |
1616 | ||
9f4801e3 SR |
1617 | static void ftrace_match_records(char *buff, int len, int enable) |
1618 | { | |
6a24a244 | 1619 | unsigned int search_len; |
9f4801e3 SR |
1620 | struct ftrace_page *pg; |
1621 | struct dyn_ftrace *rec; | |
6a24a244 SR |
1622 | unsigned long flag; |
1623 | char *search; | |
9f4801e3 | 1624 | int type; |
9f4801e3 SR |
1625 | int not; |
1626 | ||
6a24a244 | 1627 | flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
9f4801e3 SR |
1628 | type = ftrace_setup_glob(buff, len, &search, ¬); |
1629 | ||
1630 | search_len = strlen(search); | |
1631 | ||
52baf119 | 1632 | mutex_lock(&ftrace_lock); |
265c831c | 1633 | do_for_each_ftrace_rec(pg, rec) { |
265c831c SR |
1634 | |
1635 | if (rec->flags & FTRACE_FL_FAILED) | |
1636 | continue; | |
9f4801e3 SR |
1637 | |
1638 | if (ftrace_match_record(rec, search, search_len, type)) { | |
265c831c SR |
1639 | if (not) |
1640 | rec->flags &= ~flag; | |
1641 | else | |
1642 | rec->flags |= flag; | |
1643 | } | |
e68746a2 SR |
1644 | /* |
1645 | * Only enable filtering if we have a function that | |
1646 | * is filtered on. | |
1647 | */ | |
1648 | if (enable && (rec->flags & FTRACE_FL_FILTER)) | |
1649 | ftrace_filtered = 1; | |
265c831c | 1650 | } while_for_each_ftrace_rec(); |
52baf119 | 1651 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
1652 | } |
1653 | ||
64e7c440 SR |
1654 | static int |
1655 | ftrace_match_module_record(struct dyn_ftrace *rec, char *mod, | |
1656 | char *regex, int len, int type) | |
1657 | { | |
1658 | char str[KSYM_SYMBOL_LEN]; | |
1659 | char *modname; | |
1660 | ||
1661 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); | |
1662 | ||
1663 | if (!modname || strcmp(modname, mod)) | |
1664 | return 0; | |
1665 | ||
1666 | /* blank search means to match all funcs in the mod */ | |
1667 | if (len) | |
1668 | return ftrace_match(str, regex, len, type); | |
1669 | else | |
1670 | return 1; | |
1671 | } | |
1672 | ||
1673 | static void ftrace_match_module_records(char *buff, char *mod, int enable) | |
1674 | { | |
6a24a244 | 1675 | unsigned search_len = 0; |
64e7c440 SR |
1676 | struct ftrace_page *pg; |
1677 | struct dyn_ftrace *rec; | |
1678 | int type = MATCH_FULL; | |
6a24a244 SR |
1679 | char *search = buff; |
1680 | unsigned long flag; | |
64e7c440 SR |
1681 | int not = 0; |
1682 | ||
6a24a244 SR |
1683 | flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
1684 | ||
64e7c440 SR |
1685 | /* blank or '*' mean the same */ |
1686 | if (strcmp(buff, "*") == 0) | |
1687 | buff[0] = 0; | |
1688 | ||
1689 | /* handle the case of 'dont filter this module' */ | |
1690 | if (strcmp(buff, "!") == 0 || strcmp(buff, "!*") == 0) { | |
1691 | buff[0] = 0; | |
1692 | not = 1; | |
1693 | } | |
1694 | ||
1695 | if (strlen(buff)) { | |
1696 | type = ftrace_setup_glob(buff, strlen(buff), &search, ¬); | |
1697 | search_len = strlen(search); | |
1698 | } | |
1699 | ||
52baf119 | 1700 | mutex_lock(&ftrace_lock); |
64e7c440 SR |
1701 | do_for_each_ftrace_rec(pg, rec) { |
1702 | ||
1703 | if (rec->flags & FTRACE_FL_FAILED) | |
1704 | continue; | |
1705 | ||
1706 | if (ftrace_match_module_record(rec, mod, | |
1707 | search, search_len, type)) { | |
1708 | if (not) | |
1709 | rec->flags &= ~flag; | |
1710 | else | |
1711 | rec->flags |= flag; | |
1712 | } | |
e68746a2 SR |
1713 | if (enable && (rec->flags & FTRACE_FL_FILTER)) |
1714 | ftrace_filtered = 1; | |
64e7c440 SR |
1715 | |
1716 | } while_for_each_ftrace_rec(); | |
52baf119 | 1717 | mutex_unlock(&ftrace_lock); |
64e7c440 SR |
1718 | } |
1719 | ||
f6180773 SR |
1720 | /* |
1721 | * We register the module command as a template to show others how | |
1722 | * to register the a command as well. | |
1723 | */ | |
1724 | ||
1725 | static int | |
1726 | ftrace_mod_callback(char *func, char *cmd, char *param, int enable) | |
1727 | { | |
1728 | char *mod; | |
1729 | ||
1730 | /* | |
1731 | * cmd == 'mod' because we only registered this func | |
1732 | * for the 'mod' ftrace_func_command. | |
1733 | * But if you register one func with multiple commands, | |
1734 | * you can tell which command was used by the cmd | |
1735 | * parameter. | |
1736 | */ | |
1737 | ||
1738 | /* we must have a module name */ | |
1739 | if (!param) | |
1740 | return -EINVAL; | |
1741 | ||
1742 | mod = strsep(¶m, ":"); | |
1743 | if (!strlen(mod)) | |
1744 | return -EINVAL; | |
1745 | ||
1746 | ftrace_match_module_records(func, mod, enable); | |
1747 | return 0; | |
1748 | } | |
1749 | ||
1750 | static struct ftrace_func_command ftrace_mod_cmd = { | |
1751 | .name = "mod", | |
1752 | .func = ftrace_mod_callback, | |
1753 | }; | |
1754 | ||
1755 | static int __init ftrace_mod_cmd_init(void) | |
1756 | { | |
1757 | return register_ftrace_command(&ftrace_mod_cmd); | |
1758 | } | |
1759 | device_initcall(ftrace_mod_cmd_init); | |
1760 | ||
59df055f | 1761 | static void |
b6887d79 | 1762 | function_trace_probe_call(unsigned long ip, unsigned long parent_ip) |
59df055f | 1763 | { |
b6887d79 | 1764 | struct ftrace_func_probe *entry; |
59df055f SR |
1765 | struct hlist_head *hhd; |
1766 | struct hlist_node *n; | |
1767 | unsigned long key; | |
1768 | int resched; | |
1769 | ||
1770 | key = hash_long(ip, FTRACE_HASH_BITS); | |
1771 | ||
1772 | hhd = &ftrace_func_hash[key]; | |
1773 | ||
1774 | if (hlist_empty(hhd)) | |
1775 | return; | |
1776 | ||
1777 | /* | |
1778 | * Disable preemption for these calls to prevent a RCU grace | |
1779 | * period. This syncs the hash iteration and freeing of items | |
1780 | * on the hash. rcu_read_lock is too dangerous here. | |
1781 | */ | |
1782 | resched = ftrace_preempt_disable(); | |
1783 | hlist_for_each_entry_rcu(entry, n, hhd, node) { | |
1784 | if (entry->ip == ip) | |
1785 | entry->ops->func(ip, parent_ip, &entry->data); | |
1786 | } | |
1787 | ftrace_preempt_enable(resched); | |
1788 | } | |
1789 | ||
b6887d79 | 1790 | static struct ftrace_ops trace_probe_ops __read_mostly = |
59df055f | 1791 | { |
b6887d79 | 1792 | .func = function_trace_probe_call, |
59df055f SR |
1793 | }; |
1794 | ||
b6887d79 | 1795 | static int ftrace_probe_registered; |
59df055f | 1796 | |
b6887d79 | 1797 | static void __enable_ftrace_function_probe(void) |
59df055f SR |
1798 | { |
1799 | int i; | |
1800 | ||
b6887d79 | 1801 | if (ftrace_probe_registered) |
59df055f SR |
1802 | return; |
1803 | ||
1804 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
1805 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
1806 | if (hhd->first) | |
1807 | break; | |
1808 | } | |
1809 | /* Nothing registered? */ | |
1810 | if (i == FTRACE_FUNC_HASHSIZE) | |
1811 | return; | |
1812 | ||
b6887d79 | 1813 | __register_ftrace_function(&trace_probe_ops); |
59df055f | 1814 | ftrace_startup(0); |
b6887d79 | 1815 | ftrace_probe_registered = 1; |
59df055f SR |
1816 | } |
1817 | ||
b6887d79 | 1818 | static void __disable_ftrace_function_probe(void) |
59df055f SR |
1819 | { |
1820 | int i; | |
1821 | ||
b6887d79 | 1822 | if (!ftrace_probe_registered) |
59df055f SR |
1823 | return; |
1824 | ||
1825 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
1826 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
1827 | if (hhd->first) | |
1828 | return; | |
1829 | } | |
1830 | ||
1831 | /* no more funcs left */ | |
b6887d79 | 1832 | __unregister_ftrace_function(&trace_probe_ops); |
59df055f | 1833 | ftrace_shutdown(0); |
b6887d79 | 1834 | ftrace_probe_registered = 0; |
59df055f SR |
1835 | } |
1836 | ||
1837 | ||
1838 | static void ftrace_free_entry_rcu(struct rcu_head *rhp) | |
1839 | { | |
b6887d79 SR |
1840 | struct ftrace_func_probe *entry = |
1841 | container_of(rhp, struct ftrace_func_probe, rcu); | |
59df055f SR |
1842 | |
1843 | if (entry->ops->free) | |
1844 | entry->ops->free(&entry->data); | |
1845 | kfree(entry); | |
1846 | } | |
1847 | ||
1848 | ||
1849 | int | |
b6887d79 | 1850 | register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
1851 | void *data) |
1852 | { | |
b6887d79 | 1853 | struct ftrace_func_probe *entry; |
59df055f SR |
1854 | struct ftrace_page *pg; |
1855 | struct dyn_ftrace *rec; | |
59df055f | 1856 | int type, len, not; |
6a24a244 | 1857 | unsigned long key; |
59df055f SR |
1858 | int count = 0; |
1859 | char *search; | |
1860 | ||
1861 | type = ftrace_setup_glob(glob, strlen(glob), &search, ¬); | |
1862 | len = strlen(search); | |
1863 | ||
b6887d79 | 1864 | /* we do not support '!' for function probes */ |
59df055f SR |
1865 | if (WARN_ON(not)) |
1866 | return -EINVAL; | |
1867 | ||
1868 | mutex_lock(&ftrace_lock); | |
1869 | do_for_each_ftrace_rec(pg, rec) { | |
1870 | ||
1871 | if (rec->flags & FTRACE_FL_FAILED) | |
1872 | continue; | |
1873 | ||
1874 | if (!ftrace_match_record(rec, search, len, type)) | |
1875 | continue; | |
1876 | ||
1877 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
1878 | if (!entry) { | |
b6887d79 | 1879 | /* If we did not process any, then return error */ |
59df055f SR |
1880 | if (!count) |
1881 | count = -ENOMEM; | |
1882 | goto out_unlock; | |
1883 | } | |
1884 | ||
1885 | count++; | |
1886 | ||
1887 | entry->data = data; | |
1888 | ||
1889 | /* | |
1890 | * The caller might want to do something special | |
1891 | * for each function we find. We call the callback | |
1892 | * to give the caller an opportunity to do so. | |
1893 | */ | |
1894 | if (ops->callback) { | |
1895 | if (ops->callback(rec->ip, &entry->data) < 0) { | |
1896 | /* caller does not like this func */ | |
1897 | kfree(entry); | |
1898 | continue; | |
1899 | } | |
1900 | } | |
1901 | ||
1902 | entry->ops = ops; | |
1903 | entry->ip = rec->ip; | |
1904 | ||
1905 | key = hash_long(entry->ip, FTRACE_HASH_BITS); | |
1906 | hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]); | |
1907 | ||
1908 | } while_for_each_ftrace_rec(); | |
b6887d79 | 1909 | __enable_ftrace_function_probe(); |
59df055f SR |
1910 | |
1911 | out_unlock: | |
1912 | mutex_unlock(&ftrace_lock); | |
1913 | ||
1914 | return count; | |
1915 | } | |
1916 | ||
1917 | enum { | |
b6887d79 SR |
1918 | PROBE_TEST_FUNC = 1, |
1919 | PROBE_TEST_DATA = 2 | |
59df055f SR |
1920 | }; |
1921 | ||
1922 | static void | |
b6887d79 | 1923 | __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
1924 | void *data, int flags) |
1925 | { | |
b6887d79 | 1926 | struct ftrace_func_probe *entry; |
59df055f SR |
1927 | struct hlist_node *n, *tmp; |
1928 | char str[KSYM_SYMBOL_LEN]; | |
1929 | int type = MATCH_FULL; | |
1930 | int i, len = 0; | |
1931 | char *search; | |
1932 | ||
1933 | if (glob && (strcmp(glob, "*") || !strlen(glob))) | |
1934 | glob = NULL; | |
1935 | else { | |
1936 | int not; | |
1937 | ||
1938 | type = ftrace_setup_glob(glob, strlen(glob), &search, ¬); | |
1939 | len = strlen(search); | |
1940 | ||
b6887d79 | 1941 | /* we do not support '!' for function probes */ |
59df055f SR |
1942 | if (WARN_ON(not)) |
1943 | return; | |
1944 | } | |
1945 | ||
1946 | mutex_lock(&ftrace_lock); | |
1947 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
1948 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
1949 | ||
1950 | hlist_for_each_entry_safe(entry, n, tmp, hhd, node) { | |
1951 | ||
1952 | /* break up if statements for readability */ | |
b6887d79 | 1953 | if ((flags & PROBE_TEST_FUNC) && entry->ops != ops) |
59df055f SR |
1954 | continue; |
1955 | ||
b6887d79 | 1956 | if ((flags & PROBE_TEST_DATA) && entry->data != data) |
59df055f SR |
1957 | continue; |
1958 | ||
1959 | /* do this last, since it is the most expensive */ | |
1960 | if (glob) { | |
1961 | kallsyms_lookup(entry->ip, NULL, NULL, | |
1962 | NULL, str); | |
1963 | if (!ftrace_match(str, glob, len, type)) | |
1964 | continue; | |
1965 | } | |
1966 | ||
1967 | hlist_del(&entry->node); | |
1968 | call_rcu(&entry->rcu, ftrace_free_entry_rcu); | |
1969 | } | |
1970 | } | |
b6887d79 | 1971 | __disable_ftrace_function_probe(); |
59df055f SR |
1972 | mutex_unlock(&ftrace_lock); |
1973 | } | |
1974 | ||
1975 | void | |
b6887d79 | 1976 | unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
1977 | void *data) |
1978 | { | |
b6887d79 SR |
1979 | __unregister_ftrace_function_probe(glob, ops, data, |
1980 | PROBE_TEST_FUNC | PROBE_TEST_DATA); | |
59df055f SR |
1981 | } |
1982 | ||
1983 | void | |
b6887d79 | 1984 | unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops) |
59df055f | 1985 | { |
b6887d79 | 1986 | __unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC); |
59df055f SR |
1987 | } |
1988 | ||
b6887d79 | 1989 | void unregister_ftrace_function_probe_all(char *glob) |
59df055f | 1990 | { |
b6887d79 | 1991 | __unregister_ftrace_function_probe(glob, NULL, NULL, 0); |
59df055f SR |
1992 | } |
1993 | ||
f6180773 SR |
1994 | static LIST_HEAD(ftrace_commands); |
1995 | static DEFINE_MUTEX(ftrace_cmd_mutex); | |
1996 | ||
1997 | int register_ftrace_command(struct ftrace_func_command *cmd) | |
1998 | { | |
1999 | struct ftrace_func_command *p; | |
2000 | int ret = 0; | |
2001 | ||
2002 | mutex_lock(&ftrace_cmd_mutex); | |
2003 | list_for_each_entry(p, &ftrace_commands, list) { | |
2004 | if (strcmp(cmd->name, p->name) == 0) { | |
2005 | ret = -EBUSY; | |
2006 | goto out_unlock; | |
2007 | } | |
2008 | } | |
2009 | list_add(&cmd->list, &ftrace_commands); | |
2010 | out_unlock: | |
2011 | mutex_unlock(&ftrace_cmd_mutex); | |
2012 | ||
2013 | return ret; | |
2014 | } | |
2015 | ||
2016 | int unregister_ftrace_command(struct ftrace_func_command *cmd) | |
2017 | { | |
2018 | struct ftrace_func_command *p, *n; | |
2019 | int ret = -ENODEV; | |
2020 | ||
2021 | mutex_lock(&ftrace_cmd_mutex); | |
2022 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { | |
2023 | if (strcmp(cmd->name, p->name) == 0) { | |
2024 | ret = 0; | |
2025 | list_del_init(&p->list); | |
2026 | goto out_unlock; | |
2027 | } | |
2028 | } | |
2029 | out_unlock: | |
2030 | mutex_unlock(&ftrace_cmd_mutex); | |
2031 | ||
2032 | return ret; | |
2033 | } | |
2034 | ||
64e7c440 SR |
2035 | static int ftrace_process_regex(char *buff, int len, int enable) |
2036 | { | |
f6180773 | 2037 | char *func, *command, *next = buff; |
6a24a244 | 2038 | struct ftrace_func_command *p; |
f6180773 | 2039 | int ret = -EINVAL; |
64e7c440 SR |
2040 | |
2041 | func = strsep(&next, ":"); | |
2042 | ||
2043 | if (!next) { | |
2044 | ftrace_match_records(func, len, enable); | |
2045 | return 0; | |
2046 | } | |
2047 | ||
f6180773 | 2048 | /* command found */ |
64e7c440 SR |
2049 | |
2050 | command = strsep(&next, ":"); | |
2051 | ||
f6180773 SR |
2052 | mutex_lock(&ftrace_cmd_mutex); |
2053 | list_for_each_entry(p, &ftrace_commands, list) { | |
2054 | if (strcmp(p->name, command) == 0) { | |
2055 | ret = p->func(func, command, next, enable); | |
2056 | goto out_unlock; | |
2057 | } | |
64e7c440 | 2058 | } |
f6180773 SR |
2059 | out_unlock: |
2060 | mutex_unlock(&ftrace_cmd_mutex); | |
64e7c440 | 2061 | |
f6180773 | 2062 | return ret; |
64e7c440 SR |
2063 | } |
2064 | ||
e309b41d | 2065 | static ssize_t |
41c52c0d SR |
2066 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
2067 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
2068 | { |
2069 | struct ftrace_iterator *iter; | |
2070 | char ch; | |
2071 | size_t read = 0; | |
2072 | ssize_t ret; | |
2073 | ||
2074 | if (!cnt || cnt < 0) | |
2075 | return 0; | |
2076 | ||
41c52c0d | 2077 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
2078 | |
2079 | if (file->f_mode & FMODE_READ) { | |
2080 | struct seq_file *m = file->private_data; | |
2081 | iter = m->private; | |
2082 | } else | |
2083 | iter = file->private_data; | |
2084 | ||
2085 | if (!*ppos) { | |
2086 | iter->flags &= ~FTRACE_ITER_CONT; | |
2087 | iter->buffer_idx = 0; | |
2088 | } | |
2089 | ||
2090 | ret = get_user(ch, ubuf++); | |
2091 | if (ret) | |
2092 | goto out; | |
2093 | read++; | |
2094 | cnt--; | |
2095 | ||
2096 | if (!(iter->flags & ~FTRACE_ITER_CONT)) { | |
2097 | /* skip white space */ | |
2098 | while (cnt && isspace(ch)) { | |
2099 | ret = get_user(ch, ubuf++); | |
2100 | if (ret) | |
2101 | goto out; | |
2102 | read++; | |
2103 | cnt--; | |
2104 | } | |
2105 | ||
5072c59f SR |
2106 | if (isspace(ch)) { |
2107 | file->f_pos += read; | |
2108 | ret = read; | |
2109 | goto out; | |
2110 | } | |
2111 | ||
2112 | iter->buffer_idx = 0; | |
2113 | } | |
2114 | ||
2115 | while (cnt && !isspace(ch)) { | |
2116 | if (iter->buffer_idx < FTRACE_BUFF_MAX) | |
2117 | iter->buffer[iter->buffer_idx++] = ch; | |
2118 | else { | |
2119 | ret = -EINVAL; | |
2120 | goto out; | |
2121 | } | |
2122 | ret = get_user(ch, ubuf++); | |
2123 | if (ret) | |
2124 | goto out; | |
2125 | read++; | |
2126 | cnt--; | |
2127 | } | |
2128 | ||
2129 | if (isspace(ch)) { | |
2130 | iter->filtered++; | |
2131 | iter->buffer[iter->buffer_idx] = 0; | |
64e7c440 SR |
2132 | ret = ftrace_process_regex(iter->buffer, |
2133 | iter->buffer_idx, enable); | |
2134 | if (ret) | |
2135 | goto out; | |
5072c59f SR |
2136 | iter->buffer_idx = 0; |
2137 | } else | |
2138 | iter->flags |= FTRACE_ITER_CONT; | |
2139 | ||
2140 | ||
2141 | file->f_pos += read; | |
2142 | ||
2143 | ret = read; | |
2144 | out: | |
41c52c0d | 2145 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
2146 | |
2147 | return ret; | |
2148 | } | |
2149 | ||
41c52c0d SR |
2150 | static ssize_t |
2151 | ftrace_filter_write(struct file *file, const char __user *ubuf, | |
2152 | size_t cnt, loff_t *ppos) | |
2153 | { | |
2154 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
2155 | } | |
2156 | ||
2157 | static ssize_t | |
2158 | ftrace_notrace_write(struct file *file, const char __user *ubuf, | |
2159 | size_t cnt, loff_t *ppos) | |
2160 | { | |
2161 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
2162 | } | |
2163 | ||
2164 | static void | |
2165 | ftrace_set_regex(unsigned char *buf, int len, int reset, int enable) | |
2166 | { | |
2167 | if (unlikely(ftrace_disabled)) | |
2168 | return; | |
2169 | ||
2170 | mutex_lock(&ftrace_regex_lock); | |
2171 | if (reset) | |
2172 | ftrace_filter_reset(enable); | |
2173 | if (buf) | |
7f24b31b | 2174 | ftrace_match_records(buf, len, enable); |
41c52c0d SR |
2175 | mutex_unlock(&ftrace_regex_lock); |
2176 | } | |
2177 | ||
77a2b37d SR |
2178 | /** |
2179 | * ftrace_set_filter - set a function to filter on in ftrace | |
2180 | * @buf - the string that holds the function filter text. | |
2181 | * @len - the length of the string. | |
2182 | * @reset - non zero to reset all filters before applying this filter. | |
2183 | * | |
2184 | * Filters denote which functions should be enabled when tracing is enabled. | |
2185 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
2186 | */ | |
e309b41d | 2187 | void ftrace_set_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 2188 | { |
41c52c0d SR |
2189 | ftrace_set_regex(buf, len, reset, 1); |
2190 | } | |
4eebcc81 | 2191 | |
41c52c0d SR |
2192 | /** |
2193 | * ftrace_set_notrace - set a function to not trace in ftrace | |
2194 | * @buf - the string that holds the function notrace text. | |
2195 | * @len - the length of the string. | |
2196 | * @reset - non zero to reset all filters before applying this filter. | |
2197 | * | |
2198 | * Notrace Filters denote which functions should not be enabled when tracing | |
2199 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
2200 | * for tracing. | |
2201 | */ | |
2202 | void ftrace_set_notrace(unsigned char *buf, int len, int reset) | |
2203 | { | |
2204 | ftrace_set_regex(buf, len, reset, 0); | |
77a2b37d SR |
2205 | } |
2206 | ||
e309b41d | 2207 | static int |
41c52c0d | 2208 | ftrace_regex_release(struct inode *inode, struct file *file, int enable) |
5072c59f SR |
2209 | { |
2210 | struct seq_file *m = (struct seq_file *)file->private_data; | |
2211 | struct ftrace_iterator *iter; | |
2212 | ||
41c52c0d | 2213 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
2214 | if (file->f_mode & FMODE_READ) { |
2215 | iter = m->private; | |
2216 | ||
2217 | seq_release(inode, file); | |
2218 | } else | |
2219 | iter = file->private_data; | |
2220 | ||
2221 | if (iter->buffer_idx) { | |
2222 | iter->filtered++; | |
2223 | iter->buffer[iter->buffer_idx] = 0; | |
7f24b31b | 2224 | ftrace_match_records(iter->buffer, iter->buffer_idx, enable); |
5072c59f SR |
2225 | } |
2226 | ||
e6ea44e9 | 2227 | mutex_lock(&ftrace_lock); |
ee02a2e5 | 2228 | if (ftrace_start_up && ftrace_enabled) |
5072c59f | 2229 | ftrace_run_update_code(FTRACE_ENABLE_CALLS); |
e6ea44e9 | 2230 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
2231 | |
2232 | kfree(iter); | |
41c52c0d | 2233 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
2234 | return 0; |
2235 | } | |
2236 | ||
41c52c0d SR |
2237 | static int |
2238 | ftrace_filter_release(struct inode *inode, struct file *file) | |
2239 | { | |
2240 | return ftrace_regex_release(inode, file, 1); | |
2241 | } | |
2242 | ||
2243 | static int | |
2244 | ftrace_notrace_release(struct inode *inode, struct file *file) | |
2245 | { | |
2246 | return ftrace_regex_release(inode, file, 0); | |
2247 | } | |
2248 | ||
5e2336a0 | 2249 | static const struct file_operations ftrace_avail_fops = { |
5072c59f SR |
2250 | .open = ftrace_avail_open, |
2251 | .read = seq_read, | |
2252 | .llseek = seq_lseek, | |
2253 | .release = ftrace_avail_release, | |
2254 | }; | |
2255 | ||
5e2336a0 | 2256 | static const struct file_operations ftrace_failures_fops = { |
eb9a7bf0 AS |
2257 | .open = ftrace_failures_open, |
2258 | .read = seq_read, | |
2259 | .llseek = seq_lseek, | |
2260 | .release = ftrace_avail_release, | |
2261 | }; | |
2262 | ||
5e2336a0 | 2263 | static const struct file_operations ftrace_filter_fops = { |
5072c59f | 2264 | .open = ftrace_filter_open, |
850a80cf | 2265 | .read = seq_read, |
5072c59f | 2266 | .write = ftrace_filter_write, |
41c52c0d | 2267 | .llseek = ftrace_regex_lseek, |
5072c59f SR |
2268 | .release = ftrace_filter_release, |
2269 | }; | |
2270 | ||
5e2336a0 | 2271 | static const struct file_operations ftrace_notrace_fops = { |
41c52c0d | 2272 | .open = ftrace_notrace_open, |
850a80cf | 2273 | .read = seq_read, |
41c52c0d SR |
2274 | .write = ftrace_notrace_write, |
2275 | .llseek = ftrace_regex_lseek, | |
2276 | .release = ftrace_notrace_release, | |
2277 | }; | |
2278 | ||
ea4e2bc4 SR |
2279 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
2280 | ||
2281 | static DEFINE_MUTEX(graph_lock); | |
2282 | ||
2283 | int ftrace_graph_count; | |
2284 | unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; | |
2285 | ||
2286 | static void * | |
2287 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
2288 | { | |
2289 | unsigned long *array = m->private; | |
2290 | int index = *pos; | |
2291 | ||
2292 | (*pos)++; | |
2293 | ||
2294 | if (index >= ftrace_graph_count) | |
2295 | return NULL; | |
2296 | ||
2297 | return &array[index]; | |
2298 | } | |
2299 | ||
2300 | static void *g_start(struct seq_file *m, loff_t *pos) | |
2301 | { | |
2302 | void *p = NULL; | |
2303 | ||
2304 | mutex_lock(&graph_lock); | |
2305 | ||
f9349a8f FW |
2306 | /* Nothing, tell g_show to print all functions are enabled */ |
2307 | if (!ftrace_graph_count && !*pos) | |
2308 | return (void *)1; | |
2309 | ||
ea4e2bc4 SR |
2310 | p = g_next(m, p, pos); |
2311 | ||
2312 | return p; | |
2313 | } | |
2314 | ||
2315 | static void g_stop(struct seq_file *m, void *p) | |
2316 | { | |
2317 | mutex_unlock(&graph_lock); | |
2318 | } | |
2319 | ||
2320 | static int g_show(struct seq_file *m, void *v) | |
2321 | { | |
2322 | unsigned long *ptr = v; | |
2323 | char str[KSYM_SYMBOL_LEN]; | |
2324 | ||
2325 | if (!ptr) | |
2326 | return 0; | |
2327 | ||
f9349a8f FW |
2328 | if (ptr == (unsigned long *)1) { |
2329 | seq_printf(m, "#### all functions enabled ####\n"); | |
2330 | return 0; | |
2331 | } | |
2332 | ||
ea4e2bc4 SR |
2333 | kallsyms_lookup(*ptr, NULL, NULL, NULL, str); |
2334 | ||
2335 | seq_printf(m, "%s\n", str); | |
2336 | ||
2337 | return 0; | |
2338 | } | |
2339 | ||
2340 | static struct seq_operations ftrace_graph_seq_ops = { | |
2341 | .start = g_start, | |
2342 | .next = g_next, | |
2343 | .stop = g_stop, | |
2344 | .show = g_show, | |
2345 | }; | |
2346 | ||
2347 | static int | |
2348 | ftrace_graph_open(struct inode *inode, struct file *file) | |
2349 | { | |
2350 | int ret = 0; | |
2351 | ||
2352 | if (unlikely(ftrace_disabled)) | |
2353 | return -ENODEV; | |
2354 | ||
2355 | mutex_lock(&graph_lock); | |
2356 | if ((file->f_mode & FMODE_WRITE) && | |
2357 | !(file->f_flags & O_APPEND)) { | |
2358 | ftrace_graph_count = 0; | |
2359 | memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); | |
2360 | } | |
2361 | ||
2362 | if (file->f_mode & FMODE_READ) { | |
2363 | ret = seq_open(file, &ftrace_graph_seq_ops); | |
2364 | if (!ret) { | |
2365 | struct seq_file *m = file->private_data; | |
2366 | m->private = ftrace_graph_funcs; | |
2367 | } | |
2368 | } else | |
2369 | file->private_data = ftrace_graph_funcs; | |
2370 | mutex_unlock(&graph_lock); | |
2371 | ||
2372 | return ret; | |
2373 | } | |
2374 | ||
ea4e2bc4 | 2375 | static int |
f9349a8f | 2376 | ftrace_set_func(unsigned long *array, int *idx, char *buffer) |
ea4e2bc4 | 2377 | { |
ea4e2bc4 SR |
2378 | struct dyn_ftrace *rec; |
2379 | struct ftrace_page *pg; | |
f9349a8f | 2380 | int search_len; |
ea4e2bc4 | 2381 | int found = 0; |
f9349a8f FW |
2382 | int type, not; |
2383 | char *search; | |
2384 | bool exists; | |
2385 | int i; | |
ea4e2bc4 SR |
2386 | |
2387 | if (ftrace_disabled) | |
2388 | return -ENODEV; | |
2389 | ||
f9349a8f FW |
2390 | /* decode regex */ |
2391 | type = ftrace_setup_glob(buffer, strlen(buffer), &search, ¬); | |
2392 | if (not) | |
2393 | return -EINVAL; | |
2394 | ||
2395 | search_len = strlen(search); | |
2396 | ||
52baf119 | 2397 | mutex_lock(&ftrace_lock); |
265c831c SR |
2398 | do_for_each_ftrace_rec(pg, rec) { |
2399 | ||
f9349a8f FW |
2400 | if (*idx >= FTRACE_GRAPH_MAX_FUNCS) |
2401 | break; | |
2402 | ||
265c831c SR |
2403 | if (rec->flags & (FTRACE_FL_FAILED | FTRACE_FL_FREE)) |
2404 | continue; | |
2405 | ||
f9349a8f FW |
2406 | if (ftrace_match_record(rec, search, search_len, type)) { |
2407 | /* ensure it is not already in the array */ | |
2408 | exists = false; | |
2409 | for (i = 0; i < *idx; i++) | |
2410 | if (array[i] == rec->ip) { | |
2411 | exists = true; | |
265c831c SR |
2412 | break; |
2413 | } | |
f9349a8f FW |
2414 | if (!exists) { |
2415 | array[(*idx)++] = rec->ip; | |
2416 | found = 1; | |
2417 | } | |
ea4e2bc4 | 2418 | } |
265c831c | 2419 | } while_for_each_ftrace_rec(); |
f9349a8f | 2420 | |
52baf119 | 2421 | mutex_unlock(&ftrace_lock); |
ea4e2bc4 SR |
2422 | |
2423 | return found ? 0 : -EINVAL; | |
2424 | } | |
2425 | ||
2426 | static ssize_t | |
2427 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
2428 | size_t cnt, loff_t *ppos) | |
2429 | { | |
2430 | unsigned char buffer[FTRACE_BUFF_MAX+1]; | |
2431 | unsigned long *array; | |
2432 | size_t read = 0; | |
2433 | ssize_t ret; | |
2434 | int index = 0; | |
2435 | char ch; | |
2436 | ||
2437 | if (!cnt || cnt < 0) | |
2438 | return 0; | |
2439 | ||
2440 | mutex_lock(&graph_lock); | |
2441 | ||
2442 | if (ftrace_graph_count >= FTRACE_GRAPH_MAX_FUNCS) { | |
2443 | ret = -EBUSY; | |
2444 | goto out; | |
2445 | } | |
2446 | ||
2447 | if (file->f_mode & FMODE_READ) { | |
2448 | struct seq_file *m = file->private_data; | |
2449 | array = m->private; | |
2450 | } else | |
2451 | array = file->private_data; | |
2452 | ||
2453 | ret = get_user(ch, ubuf++); | |
2454 | if (ret) | |
2455 | goto out; | |
2456 | read++; | |
2457 | cnt--; | |
2458 | ||
2459 | /* skip white space */ | |
2460 | while (cnt && isspace(ch)) { | |
2461 | ret = get_user(ch, ubuf++); | |
2462 | if (ret) | |
2463 | goto out; | |
2464 | read++; | |
2465 | cnt--; | |
2466 | } | |
2467 | ||
2468 | if (isspace(ch)) { | |
2469 | *ppos += read; | |
2470 | ret = read; | |
2471 | goto out; | |
2472 | } | |
2473 | ||
2474 | while (cnt && !isspace(ch)) { | |
2475 | if (index < FTRACE_BUFF_MAX) | |
2476 | buffer[index++] = ch; | |
2477 | else { | |
2478 | ret = -EINVAL; | |
2479 | goto out; | |
2480 | } | |
2481 | ret = get_user(ch, ubuf++); | |
2482 | if (ret) | |
2483 | goto out; | |
2484 | read++; | |
2485 | cnt--; | |
2486 | } | |
2487 | buffer[index] = 0; | |
2488 | ||
f9349a8f FW |
2489 | /* we allow only one expression at a time */ |
2490 | ret = ftrace_set_func(array, &ftrace_graph_count, buffer); | |
ea4e2bc4 SR |
2491 | if (ret) |
2492 | goto out; | |
2493 | ||
ea4e2bc4 SR |
2494 | file->f_pos += read; |
2495 | ||
2496 | ret = read; | |
2497 | out: | |
2498 | mutex_unlock(&graph_lock); | |
2499 | ||
2500 | return ret; | |
2501 | } | |
2502 | ||
2503 | static const struct file_operations ftrace_graph_fops = { | |
2504 | .open = ftrace_graph_open, | |
850a80cf | 2505 | .read = seq_read, |
ea4e2bc4 SR |
2506 | .write = ftrace_graph_write, |
2507 | }; | |
2508 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
2509 | ||
df4fc315 | 2510 | static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) |
5072c59f | 2511 | { |
5072c59f SR |
2512 | struct dentry *entry; |
2513 | ||
5072c59f SR |
2514 | entry = debugfs_create_file("available_filter_functions", 0444, |
2515 | d_tracer, NULL, &ftrace_avail_fops); | |
2516 | if (!entry) | |
2517 | pr_warning("Could not create debugfs " | |
2518 | "'available_filter_functions' entry\n"); | |
2519 | ||
eb9a7bf0 AS |
2520 | entry = debugfs_create_file("failures", 0444, |
2521 | d_tracer, NULL, &ftrace_failures_fops); | |
2522 | if (!entry) | |
2523 | pr_warning("Could not create debugfs 'failures' entry\n"); | |
2524 | ||
5072c59f SR |
2525 | entry = debugfs_create_file("set_ftrace_filter", 0644, d_tracer, |
2526 | NULL, &ftrace_filter_fops); | |
2527 | if (!entry) | |
2528 | pr_warning("Could not create debugfs " | |
2529 | "'set_ftrace_filter' entry\n"); | |
41c52c0d SR |
2530 | |
2531 | entry = debugfs_create_file("set_ftrace_notrace", 0644, d_tracer, | |
2532 | NULL, &ftrace_notrace_fops); | |
2533 | if (!entry) | |
2534 | pr_warning("Could not create debugfs " | |
2535 | "'set_ftrace_notrace' entry\n"); | |
ad90c0e3 | 2536 | |
ea4e2bc4 SR |
2537 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
2538 | entry = debugfs_create_file("set_graph_function", 0444, d_tracer, | |
2539 | NULL, | |
2540 | &ftrace_graph_fops); | |
2541 | if (!entry) | |
2542 | pr_warning("Could not create debugfs " | |
2543 | "'set_graph_function' entry\n"); | |
2544 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
2545 | ||
5072c59f SR |
2546 | return 0; |
2547 | } | |
2548 | ||
31e88909 SR |
2549 | static int ftrace_convert_nops(struct module *mod, |
2550 | unsigned long *start, | |
68bf21aa SR |
2551 | unsigned long *end) |
2552 | { | |
2553 | unsigned long *p; | |
2554 | unsigned long addr; | |
2555 | unsigned long flags; | |
2556 | ||
e6ea44e9 | 2557 | mutex_lock(&ftrace_lock); |
68bf21aa SR |
2558 | p = start; |
2559 | while (p < end) { | |
2560 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
2561 | /* |
2562 | * Some architecture linkers will pad between | |
2563 | * the different mcount_loc sections of different | |
2564 | * object files to satisfy alignments. | |
2565 | * Skip any NULL pointers. | |
2566 | */ | |
2567 | if (!addr) | |
2568 | continue; | |
68bf21aa | 2569 | ftrace_record_ip(addr); |
68bf21aa SR |
2570 | } |
2571 | ||
08f5ac90 | 2572 | /* disable interrupts to prevent kstop machine */ |
68bf21aa | 2573 | local_irq_save(flags); |
31e88909 | 2574 | ftrace_update_code(mod); |
68bf21aa | 2575 | local_irq_restore(flags); |
e6ea44e9 | 2576 | mutex_unlock(&ftrace_lock); |
68bf21aa SR |
2577 | |
2578 | return 0; | |
2579 | } | |
2580 | ||
31e88909 SR |
2581 | void ftrace_init_module(struct module *mod, |
2582 | unsigned long *start, unsigned long *end) | |
90d595fe | 2583 | { |
00fd61ae | 2584 | if (ftrace_disabled || start == end) |
fed1939c | 2585 | return; |
31e88909 | 2586 | ftrace_convert_nops(mod, start, end); |
90d595fe SR |
2587 | } |
2588 | ||
68bf21aa SR |
2589 | extern unsigned long __start_mcount_loc[]; |
2590 | extern unsigned long __stop_mcount_loc[]; | |
2591 | ||
2592 | void __init ftrace_init(void) | |
2593 | { | |
2594 | unsigned long count, addr, flags; | |
2595 | int ret; | |
2596 | ||
2597 | /* Keep the ftrace pointer to the stub */ | |
2598 | addr = (unsigned long)ftrace_stub; | |
2599 | ||
2600 | local_irq_save(flags); | |
2601 | ftrace_dyn_arch_init(&addr); | |
2602 | local_irq_restore(flags); | |
2603 | ||
2604 | /* ftrace_dyn_arch_init places the return code in addr */ | |
2605 | if (addr) | |
2606 | goto failed; | |
2607 | ||
2608 | count = __stop_mcount_loc - __start_mcount_loc; | |
2609 | ||
2610 | ret = ftrace_dyn_table_alloc(count); | |
2611 | if (ret) | |
2612 | goto failed; | |
2613 | ||
2614 | last_ftrace_enabled = ftrace_enabled = 1; | |
2615 | ||
31e88909 SR |
2616 | ret = ftrace_convert_nops(NULL, |
2617 | __start_mcount_loc, | |
68bf21aa SR |
2618 | __stop_mcount_loc); |
2619 | ||
2620 | return; | |
2621 | failed: | |
2622 | ftrace_disabled = 1; | |
2623 | } | |
68bf21aa | 2624 | |
3d083395 | 2625 | #else |
0b6e4d56 FW |
2626 | |
2627 | static int __init ftrace_nodyn_init(void) | |
2628 | { | |
2629 | ftrace_enabled = 1; | |
2630 | return 0; | |
2631 | } | |
2632 | device_initcall(ftrace_nodyn_init); | |
2633 | ||
df4fc315 SR |
2634 | static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } |
2635 | static inline void ftrace_startup_enable(int command) { } | |
5a45cfe1 SR |
2636 | /* Keep as macros so we do not need to define the commands */ |
2637 | # define ftrace_startup(command) do { } while (0) | |
2638 | # define ftrace_shutdown(command) do { } while (0) | |
c7aafc54 IM |
2639 | # define ftrace_startup_sysctl() do { } while (0) |
2640 | # define ftrace_shutdown_sysctl() do { } while (0) | |
3d083395 SR |
2641 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
2642 | ||
df4fc315 SR |
2643 | static ssize_t |
2644 | ftrace_pid_read(struct file *file, char __user *ubuf, | |
2645 | size_t cnt, loff_t *ppos) | |
2646 | { | |
2647 | char buf[64]; | |
2648 | int r; | |
2649 | ||
e32d8956 SR |
2650 | if (ftrace_pid_trace == ftrace_swapper_pid) |
2651 | r = sprintf(buf, "swapper tasks\n"); | |
2652 | else if (ftrace_pid_trace) | |
cc59c9e8 | 2653 | r = sprintf(buf, "%u\n", pid_vnr(ftrace_pid_trace)); |
df4fc315 SR |
2654 | else |
2655 | r = sprintf(buf, "no pid\n"); | |
2656 | ||
2657 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
2658 | } | |
2659 | ||
e32d8956 | 2660 | static void clear_ftrace_swapper(void) |
978f3a45 SR |
2661 | { |
2662 | struct task_struct *p; | |
e32d8956 | 2663 | int cpu; |
978f3a45 | 2664 | |
e32d8956 SR |
2665 | get_online_cpus(); |
2666 | for_each_online_cpu(cpu) { | |
2667 | p = idle_task(cpu); | |
978f3a45 | 2668 | clear_tsk_trace_trace(p); |
e32d8956 SR |
2669 | } |
2670 | put_online_cpus(); | |
2671 | } | |
978f3a45 | 2672 | |
e32d8956 SR |
2673 | static void set_ftrace_swapper(void) |
2674 | { | |
2675 | struct task_struct *p; | |
2676 | int cpu; | |
2677 | ||
2678 | get_online_cpus(); | |
2679 | for_each_online_cpu(cpu) { | |
2680 | p = idle_task(cpu); | |
2681 | set_tsk_trace_trace(p); | |
2682 | } | |
2683 | put_online_cpus(); | |
978f3a45 SR |
2684 | } |
2685 | ||
e32d8956 SR |
2686 | static void clear_ftrace_pid(struct pid *pid) |
2687 | { | |
2688 | struct task_struct *p; | |
2689 | ||
229c4ef8 | 2690 | rcu_read_lock(); |
e32d8956 SR |
2691 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
2692 | clear_tsk_trace_trace(p); | |
2693 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 ON |
2694 | rcu_read_unlock(); |
2695 | ||
e32d8956 SR |
2696 | put_pid(pid); |
2697 | } | |
2698 | ||
2699 | static void set_ftrace_pid(struct pid *pid) | |
978f3a45 SR |
2700 | { |
2701 | struct task_struct *p; | |
2702 | ||
229c4ef8 | 2703 | rcu_read_lock(); |
978f3a45 SR |
2704 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
2705 | set_tsk_trace_trace(p); | |
2706 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 | 2707 | rcu_read_unlock(); |
978f3a45 SR |
2708 | } |
2709 | ||
e32d8956 SR |
2710 | static void clear_ftrace_pid_task(struct pid **pid) |
2711 | { | |
2712 | if (*pid == ftrace_swapper_pid) | |
2713 | clear_ftrace_swapper(); | |
2714 | else | |
2715 | clear_ftrace_pid(*pid); | |
2716 | ||
2717 | *pid = NULL; | |
2718 | } | |
2719 | ||
2720 | static void set_ftrace_pid_task(struct pid *pid) | |
2721 | { | |
2722 | if (pid == ftrace_swapper_pid) | |
2723 | set_ftrace_swapper(); | |
2724 | else | |
2725 | set_ftrace_pid(pid); | |
2726 | } | |
2727 | ||
df4fc315 SR |
2728 | static ssize_t |
2729 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
2730 | size_t cnt, loff_t *ppos) | |
2731 | { | |
978f3a45 | 2732 | struct pid *pid; |
df4fc315 SR |
2733 | char buf[64]; |
2734 | long val; | |
2735 | int ret; | |
2736 | ||
2737 | if (cnt >= sizeof(buf)) | |
2738 | return -EINVAL; | |
2739 | ||
2740 | if (copy_from_user(&buf, ubuf, cnt)) | |
2741 | return -EFAULT; | |
2742 | ||
2743 | buf[cnt] = 0; | |
2744 | ||
2745 | ret = strict_strtol(buf, 10, &val); | |
2746 | if (ret < 0) | |
2747 | return ret; | |
2748 | ||
e6ea44e9 | 2749 | mutex_lock(&ftrace_lock); |
978f3a45 | 2750 | if (val < 0) { |
df4fc315 | 2751 | /* disable pid tracing */ |
978f3a45 | 2752 | if (!ftrace_pid_trace) |
df4fc315 | 2753 | goto out; |
978f3a45 SR |
2754 | |
2755 | clear_ftrace_pid_task(&ftrace_pid_trace); | |
df4fc315 SR |
2756 | |
2757 | } else { | |
e32d8956 SR |
2758 | /* swapper task is special */ |
2759 | if (!val) { | |
2760 | pid = ftrace_swapper_pid; | |
2761 | if (pid == ftrace_pid_trace) | |
2762 | goto out; | |
2763 | } else { | |
2764 | pid = find_get_pid(val); | |
df4fc315 | 2765 | |
e32d8956 SR |
2766 | if (pid == ftrace_pid_trace) { |
2767 | put_pid(pid); | |
2768 | goto out; | |
2769 | } | |
0ef8cde5 | 2770 | } |
0ef8cde5 | 2771 | |
978f3a45 SR |
2772 | if (ftrace_pid_trace) |
2773 | clear_ftrace_pid_task(&ftrace_pid_trace); | |
2774 | ||
2775 | if (!pid) | |
2776 | goto out; | |
2777 | ||
2778 | ftrace_pid_trace = pid; | |
2779 | ||
2780 | set_ftrace_pid_task(ftrace_pid_trace); | |
df4fc315 SR |
2781 | } |
2782 | ||
2783 | /* update the function call */ | |
2784 | ftrace_update_pid_func(); | |
2785 | ftrace_startup_enable(0); | |
2786 | ||
2787 | out: | |
e6ea44e9 | 2788 | mutex_unlock(&ftrace_lock); |
df4fc315 SR |
2789 | |
2790 | return cnt; | |
2791 | } | |
2792 | ||
5e2336a0 | 2793 | static const struct file_operations ftrace_pid_fops = { |
df4fc315 SR |
2794 | .read = ftrace_pid_read, |
2795 | .write = ftrace_pid_write, | |
2796 | }; | |
2797 | ||
2798 | static __init int ftrace_init_debugfs(void) | |
2799 | { | |
2800 | struct dentry *d_tracer; | |
2801 | struct dentry *entry; | |
2802 | ||
2803 | d_tracer = tracing_init_dentry(); | |
2804 | if (!d_tracer) | |
2805 | return 0; | |
2806 | ||
2807 | ftrace_init_dyn_debugfs(d_tracer); | |
2808 | ||
2809 | entry = debugfs_create_file("set_ftrace_pid", 0644, d_tracer, | |
2810 | NULL, &ftrace_pid_fops); | |
2811 | if (!entry) | |
2812 | pr_warning("Could not create debugfs " | |
2813 | "'set_ftrace_pid' entry\n"); | |
493762fc SR |
2814 | |
2815 | ftrace_profile_debugfs(d_tracer); | |
2816 | ||
df4fc315 SR |
2817 | return 0; |
2818 | } | |
df4fc315 SR |
2819 | fs_initcall(ftrace_init_debugfs); |
2820 | ||
a2bb6a3d | 2821 | /** |
81adbdc0 | 2822 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
2823 | * |
2824 | * This function should be used by panic code. It stops ftrace | |
2825 | * but in a not so nice way. If you need to simply kill ftrace | |
2826 | * from a non-atomic section, use ftrace_kill. | |
2827 | */ | |
81adbdc0 | 2828 | void ftrace_kill(void) |
a2bb6a3d SR |
2829 | { |
2830 | ftrace_disabled = 1; | |
2831 | ftrace_enabled = 0; | |
a2bb6a3d SR |
2832 | clear_ftrace_function(); |
2833 | } | |
2834 | ||
16444a8a | 2835 | /** |
3d083395 SR |
2836 | * register_ftrace_function - register a function for profiling |
2837 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 2838 | * |
3d083395 SR |
2839 | * Register a function to be called by all functions in the |
2840 | * kernel. | |
2841 | * | |
2842 | * Note: @ops->func and all the functions it calls must be labeled | |
2843 | * with "notrace", otherwise it will go into a | |
2844 | * recursive loop. | |
16444a8a | 2845 | */ |
3d083395 | 2846 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 2847 | { |
b0fc494f SR |
2848 | int ret; |
2849 | ||
4eebcc81 SR |
2850 | if (unlikely(ftrace_disabled)) |
2851 | return -1; | |
2852 | ||
e6ea44e9 | 2853 | mutex_lock(&ftrace_lock); |
e7d3737e | 2854 | |
b0fc494f | 2855 | ret = __register_ftrace_function(ops); |
5a45cfe1 | 2856 | ftrace_startup(0); |
b0fc494f | 2857 | |
e6ea44e9 | 2858 | mutex_unlock(&ftrace_lock); |
b0fc494f | 2859 | return ret; |
3d083395 SR |
2860 | } |
2861 | ||
2862 | /** | |
32632920 | 2863 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
2864 | * @ops - ops structure that holds the function to unregister |
2865 | * | |
2866 | * Unregister a function that was added to be called by ftrace profiling. | |
2867 | */ | |
2868 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
2869 | { | |
2870 | int ret; | |
2871 | ||
e6ea44e9 | 2872 | mutex_lock(&ftrace_lock); |
3d083395 | 2873 | ret = __unregister_ftrace_function(ops); |
5a45cfe1 | 2874 | ftrace_shutdown(0); |
e6ea44e9 | 2875 | mutex_unlock(&ftrace_lock); |
b0fc494f SR |
2876 | |
2877 | return ret; | |
2878 | } | |
2879 | ||
e309b41d | 2880 | int |
b0fc494f | 2881 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
5072c59f | 2882 | struct file *file, void __user *buffer, size_t *lenp, |
b0fc494f SR |
2883 | loff_t *ppos) |
2884 | { | |
2885 | int ret; | |
2886 | ||
4eebcc81 SR |
2887 | if (unlikely(ftrace_disabled)) |
2888 | return -ENODEV; | |
2889 | ||
e6ea44e9 | 2890 | mutex_lock(&ftrace_lock); |
b0fc494f | 2891 | |
5072c59f | 2892 | ret = proc_dointvec(table, write, file, buffer, lenp, ppos); |
b0fc494f SR |
2893 | |
2894 | if (ret || !write || (last_ftrace_enabled == ftrace_enabled)) | |
2895 | goto out; | |
2896 | ||
2897 | last_ftrace_enabled = ftrace_enabled; | |
2898 | ||
2899 | if (ftrace_enabled) { | |
2900 | ||
2901 | ftrace_startup_sysctl(); | |
2902 | ||
2903 | /* we are starting ftrace again */ | |
2904 | if (ftrace_list != &ftrace_list_end) { | |
2905 | if (ftrace_list->next == &ftrace_list_end) | |
2906 | ftrace_trace_function = ftrace_list->func; | |
2907 | else | |
2908 | ftrace_trace_function = ftrace_list_func; | |
2909 | } | |
2910 | ||
2911 | } else { | |
2912 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
2913 | ftrace_trace_function = ftrace_stub; | |
2914 | ||
2915 | ftrace_shutdown_sysctl(); | |
2916 | } | |
2917 | ||
2918 | out: | |
e6ea44e9 | 2919 | mutex_unlock(&ftrace_lock); |
3d083395 | 2920 | return ret; |
16444a8a | 2921 | } |
f17845e5 | 2922 | |
fb52607a | 2923 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 2924 | |
287b6e68 | 2925 | static atomic_t ftrace_graph_active; |
4a2b8dda | 2926 | static struct notifier_block ftrace_suspend_notifier; |
e7d3737e | 2927 | |
e49dc19c SR |
2928 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
2929 | { | |
2930 | return 0; | |
2931 | } | |
2932 | ||
287b6e68 FW |
2933 | /* The callbacks that hook a function */ |
2934 | trace_func_graph_ret_t ftrace_graph_return = | |
2935 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 2936 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
2937 | |
2938 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
2939 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
2940 | { | |
2941 | int i; | |
2942 | int ret = 0; | |
2943 | unsigned long flags; | |
2944 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; | |
2945 | struct task_struct *g, *t; | |
2946 | ||
2947 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
2948 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
2949 | * sizeof(struct ftrace_ret_stack), | |
2950 | GFP_KERNEL); | |
2951 | if (!ret_stack_list[i]) { | |
2952 | start = 0; | |
2953 | end = i; | |
2954 | ret = -ENOMEM; | |
2955 | goto free; | |
2956 | } | |
2957 | } | |
2958 | ||
2959 | read_lock_irqsave(&tasklist_lock, flags); | |
2960 | do_each_thread(g, t) { | |
2961 | if (start == end) { | |
2962 | ret = -EAGAIN; | |
2963 | goto unlock; | |
2964 | } | |
2965 | ||
2966 | if (t->ret_stack == NULL) { | |
f201ae23 | 2967 | t->curr_ret_stack = -1; |
48d68b20 FW |
2968 | /* Make sure IRQs see the -1 first: */ |
2969 | barrier(); | |
2970 | t->ret_stack = ret_stack_list[start++]; | |
380c4b14 | 2971 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 FW |
2972 | atomic_set(&t->trace_overrun, 0); |
2973 | } | |
2974 | } while_each_thread(g, t); | |
2975 | ||
2976 | unlock: | |
2977 | read_unlock_irqrestore(&tasklist_lock, flags); | |
2978 | free: | |
2979 | for (i = start; i < end; i++) | |
2980 | kfree(ret_stack_list[i]); | |
2981 | return ret; | |
2982 | } | |
2983 | ||
8aef2d28 SR |
2984 | static void |
2985 | ftrace_graph_probe_sched_switch(struct rq *__rq, struct task_struct *prev, | |
2986 | struct task_struct *next) | |
2987 | { | |
2988 | unsigned long long timestamp; | |
2989 | int index; | |
2990 | ||
be6f164a SR |
2991 | /* |
2992 | * Does the user want to count the time a function was asleep. | |
2993 | * If so, do not update the time stamps. | |
2994 | */ | |
2995 | if (trace_flags & TRACE_ITER_SLEEP_TIME) | |
2996 | return; | |
2997 | ||
8aef2d28 SR |
2998 | timestamp = trace_clock_local(); |
2999 | ||
3000 | prev->ftrace_timestamp = timestamp; | |
3001 | ||
3002 | /* only process tasks that we timestamped */ | |
3003 | if (!next->ftrace_timestamp) | |
3004 | return; | |
3005 | ||
3006 | /* | |
3007 | * Update all the counters in next to make up for the | |
3008 | * time next was sleeping. | |
3009 | */ | |
3010 | timestamp -= next->ftrace_timestamp; | |
3011 | ||
3012 | for (index = next->curr_ret_stack; index >= 0; index--) | |
3013 | next->ret_stack[index].calltime += timestamp; | |
3014 | } | |
3015 | ||
f201ae23 | 3016 | /* Allocate a return stack for each task */ |
fb52607a | 3017 | static int start_graph_tracing(void) |
f201ae23 FW |
3018 | { |
3019 | struct ftrace_ret_stack **ret_stack_list; | |
5b058bcd | 3020 | int ret, cpu; |
f201ae23 FW |
3021 | |
3022 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
3023 | sizeof(struct ftrace_ret_stack *), | |
3024 | GFP_KERNEL); | |
3025 | ||
3026 | if (!ret_stack_list) | |
3027 | return -ENOMEM; | |
3028 | ||
5b058bcd FW |
3029 | /* The cpu_boot init_task->ret_stack will never be freed */ |
3030 | for_each_online_cpu(cpu) | |
3031 | ftrace_graph_init_task(idle_task(cpu)); | |
3032 | ||
f201ae23 FW |
3033 | do { |
3034 | ret = alloc_retstack_tasklist(ret_stack_list); | |
3035 | } while (ret == -EAGAIN); | |
3036 | ||
8aef2d28 SR |
3037 | if (!ret) { |
3038 | ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch); | |
3039 | if (ret) | |
3040 | pr_info("ftrace_graph: Couldn't activate tracepoint" | |
3041 | " probe to kernel_sched_switch\n"); | |
3042 | } | |
3043 | ||
f201ae23 FW |
3044 | kfree(ret_stack_list); |
3045 | return ret; | |
3046 | } | |
3047 | ||
4a2b8dda FW |
3048 | /* |
3049 | * Hibernation protection. | |
3050 | * The state of the current task is too much unstable during | |
3051 | * suspend/restore to disk. We want to protect against that. | |
3052 | */ | |
3053 | static int | |
3054 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, | |
3055 | void *unused) | |
3056 | { | |
3057 | switch (state) { | |
3058 | case PM_HIBERNATION_PREPARE: | |
3059 | pause_graph_tracing(); | |
3060 | break; | |
3061 | ||
3062 | case PM_POST_HIBERNATION: | |
3063 | unpause_graph_tracing(); | |
3064 | break; | |
3065 | } | |
3066 | return NOTIFY_DONE; | |
3067 | } | |
3068 | ||
287b6e68 FW |
3069 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
3070 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 3071 | { |
e7d3737e FW |
3072 | int ret = 0; |
3073 | ||
e6ea44e9 | 3074 | mutex_lock(&ftrace_lock); |
e7d3737e | 3075 | |
05ce5818 SR |
3076 | /* we currently allow only one tracer registered at a time */ |
3077 | if (atomic_read(&ftrace_graph_active)) { | |
3078 | ret = -EBUSY; | |
3079 | goto out; | |
3080 | } | |
3081 | ||
4a2b8dda FW |
3082 | ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call; |
3083 | register_pm_notifier(&ftrace_suspend_notifier); | |
3084 | ||
287b6e68 | 3085 | atomic_inc(&ftrace_graph_active); |
fb52607a | 3086 | ret = start_graph_tracing(); |
f201ae23 | 3087 | if (ret) { |
287b6e68 | 3088 | atomic_dec(&ftrace_graph_active); |
f201ae23 FW |
3089 | goto out; |
3090 | } | |
e53a6319 | 3091 | |
287b6e68 FW |
3092 | ftrace_graph_return = retfunc; |
3093 | ftrace_graph_entry = entryfunc; | |
e53a6319 | 3094 | |
5a45cfe1 | 3095 | ftrace_startup(FTRACE_START_FUNC_RET); |
e7d3737e FW |
3096 | |
3097 | out: | |
e6ea44e9 | 3098 | mutex_unlock(&ftrace_lock); |
e7d3737e | 3099 | return ret; |
15e6cb36 FW |
3100 | } |
3101 | ||
fb52607a | 3102 | void unregister_ftrace_graph(void) |
15e6cb36 | 3103 | { |
e6ea44e9 | 3104 | mutex_lock(&ftrace_lock); |
e7d3737e | 3105 | |
287b6e68 | 3106 | atomic_dec(&ftrace_graph_active); |
8aef2d28 | 3107 | unregister_trace_sched_switch(ftrace_graph_probe_sched_switch); |
287b6e68 | 3108 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; |
e49dc19c | 3109 | ftrace_graph_entry = ftrace_graph_entry_stub; |
5a45cfe1 | 3110 | ftrace_shutdown(FTRACE_STOP_FUNC_RET); |
4a2b8dda | 3111 | unregister_pm_notifier(&ftrace_suspend_notifier); |
e7d3737e | 3112 | |
e6ea44e9 | 3113 | mutex_unlock(&ftrace_lock); |
15e6cb36 | 3114 | } |
f201ae23 FW |
3115 | |
3116 | /* Allocate a return stack for newly created task */ | |
fb52607a | 3117 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 3118 | { |
287b6e68 | 3119 | if (atomic_read(&ftrace_graph_active)) { |
f201ae23 FW |
3120 | t->ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH |
3121 | * sizeof(struct ftrace_ret_stack), | |
3122 | GFP_KERNEL); | |
3123 | if (!t->ret_stack) | |
3124 | return; | |
3125 | t->curr_ret_stack = -1; | |
380c4b14 | 3126 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 | 3127 | atomic_set(&t->trace_overrun, 0); |
8aef2d28 | 3128 | t->ftrace_timestamp = 0; |
f201ae23 FW |
3129 | } else |
3130 | t->ret_stack = NULL; | |
3131 | } | |
3132 | ||
fb52607a | 3133 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 3134 | { |
eae849ca FW |
3135 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
3136 | ||
f201ae23 | 3137 | t->ret_stack = NULL; |
eae849ca FW |
3138 | /* NULL must become visible to IRQs before we free it: */ |
3139 | barrier(); | |
3140 | ||
3141 | kfree(ret_stack); | |
f201ae23 | 3142 | } |
14a866c5 SR |
3143 | |
3144 | void ftrace_graph_stop(void) | |
3145 | { | |
3146 | ftrace_stop(); | |
3147 | } | |
15e6cb36 FW |
3148 | #endif |
3149 |