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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 | |
ad8d75ff | 32 | #include <trace/events/sched.h> |
8aef2d28 | 33 | |
395a59d0 | 34 | #include <asm/ftrace.h> |
2af15d6a | 35 | #include <asm/setup.h> |
395a59d0 | 36 | |
0706f1c4 | 37 | #include "trace_output.h" |
bac429f0 | 38 | #include "trace_stat.h" |
16444a8a | 39 | |
6912896e SR |
40 | #define FTRACE_WARN_ON(cond) \ |
41 | do { \ | |
42 | if (WARN_ON(cond)) \ | |
43 | ftrace_kill(); \ | |
44 | } while (0) | |
45 | ||
46 | #define FTRACE_WARN_ON_ONCE(cond) \ | |
47 | do { \ | |
48 | if (WARN_ON_ONCE(cond)) \ | |
49 | ftrace_kill(); \ | |
50 | } while (0) | |
51 | ||
8fc0c701 SR |
52 | /* hash bits for specific function selection */ |
53 | #define FTRACE_HASH_BITS 7 | |
54 | #define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS) | |
55 | ||
4eebcc81 SR |
56 | /* ftrace_enabled is a method to turn ftrace on or off */ |
57 | int ftrace_enabled __read_mostly; | |
d61f82d0 | 58 | static int last_ftrace_enabled; |
b0fc494f | 59 | |
60a7ecf4 SR |
60 | /* Quick disabling of function tracer. */ |
61 | int function_trace_stop; | |
62 | ||
4eebcc81 SR |
63 | /* |
64 | * ftrace_disabled is set when an anomaly is discovered. | |
65 | * ftrace_disabled is much stronger than ftrace_enabled. | |
66 | */ | |
67 | static int ftrace_disabled __read_mostly; | |
68 | ||
52baf119 | 69 | static DEFINE_MUTEX(ftrace_lock); |
b0fc494f | 70 | |
16444a8a ACM |
71 | static struct ftrace_ops ftrace_list_end __read_mostly = |
72 | { | |
fb9fb015 | 73 | .func = ftrace_stub, |
16444a8a ACM |
74 | }; |
75 | ||
76 | static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end; | |
77 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; | |
60a7ecf4 | 78 | ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub; |
df4fc315 | 79 | ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub; |
16444a8a | 80 | |
f2252935 | 81 | static void ftrace_list_func(unsigned long ip, unsigned long parent_ip) |
16444a8a ACM |
82 | { |
83 | struct ftrace_ops *op = ftrace_list; | |
84 | ||
85 | /* in case someone actually ports this to alpha! */ | |
86 | read_barrier_depends(); | |
87 | ||
88 | while (op != &ftrace_list_end) { | |
89 | /* silly alpha */ | |
90 | read_barrier_depends(); | |
91 | op->func(ip, parent_ip); | |
92 | op = op->next; | |
93 | }; | |
94 | } | |
95 | ||
df4fc315 SR |
96 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip) |
97 | { | |
0ef8cde5 | 98 | if (!test_tsk_trace_trace(current)) |
df4fc315 SR |
99 | return; |
100 | ||
101 | ftrace_pid_function(ip, parent_ip); | |
102 | } | |
103 | ||
104 | static void set_ftrace_pid_function(ftrace_func_t func) | |
105 | { | |
106 | /* do not set ftrace_pid_function to itself! */ | |
107 | if (func != ftrace_pid_func) | |
108 | ftrace_pid_function = func; | |
109 | } | |
110 | ||
16444a8a | 111 | /** |
3d083395 | 112 | * clear_ftrace_function - reset the ftrace function |
16444a8a | 113 | * |
3d083395 SR |
114 | * This NULLs the ftrace function and in essence stops |
115 | * tracing. There may be lag | |
16444a8a | 116 | */ |
3d083395 | 117 | void clear_ftrace_function(void) |
16444a8a | 118 | { |
3d083395 | 119 | ftrace_trace_function = ftrace_stub; |
60a7ecf4 | 120 | __ftrace_trace_function = ftrace_stub; |
df4fc315 | 121 | ftrace_pid_function = ftrace_stub; |
3d083395 SR |
122 | } |
123 | ||
60a7ecf4 SR |
124 | #ifndef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
125 | /* | |
126 | * For those archs that do not test ftrace_trace_stop in their | |
127 | * mcount call site, we need to do it from C. | |
128 | */ | |
129 | static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip) | |
130 | { | |
131 | if (function_trace_stop) | |
132 | return; | |
133 | ||
134 | __ftrace_trace_function(ip, parent_ip); | |
135 | } | |
136 | #endif | |
137 | ||
e309b41d | 138 | static int __register_ftrace_function(struct ftrace_ops *ops) |
3d083395 | 139 | { |
16444a8a ACM |
140 | ops->next = ftrace_list; |
141 | /* | |
142 | * We are entering ops into the ftrace_list but another | |
143 | * CPU might be walking that list. We need to make sure | |
144 | * the ops->next pointer is valid before another CPU sees | |
145 | * the ops pointer included into the ftrace_list. | |
146 | */ | |
147 | smp_wmb(); | |
148 | ftrace_list = ops; | |
3d083395 | 149 | |
b0fc494f | 150 | if (ftrace_enabled) { |
df4fc315 SR |
151 | ftrace_func_t func; |
152 | ||
153 | if (ops->next == &ftrace_list_end) | |
154 | func = ops->func; | |
155 | else | |
156 | func = ftrace_list_func; | |
157 | ||
978f3a45 | 158 | if (ftrace_pid_trace) { |
df4fc315 SR |
159 | set_ftrace_pid_function(func); |
160 | func = ftrace_pid_func; | |
161 | } | |
162 | ||
b0fc494f SR |
163 | /* |
164 | * For one func, simply call it directly. | |
165 | * For more than one func, call the chain. | |
166 | */ | |
60a7ecf4 | 167 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
df4fc315 | 168 | ftrace_trace_function = func; |
60a7ecf4 | 169 | #else |
df4fc315 | 170 | __ftrace_trace_function = func; |
60a7ecf4 SR |
171 | ftrace_trace_function = ftrace_test_stop_func; |
172 | #endif | |
b0fc494f | 173 | } |
3d083395 | 174 | |
16444a8a ACM |
175 | return 0; |
176 | } | |
177 | ||
e309b41d | 178 | static int __unregister_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 179 | { |
16444a8a | 180 | struct ftrace_ops **p; |
16444a8a ACM |
181 | |
182 | /* | |
3d083395 SR |
183 | * If we are removing the last function, then simply point |
184 | * to the ftrace_stub. | |
16444a8a ACM |
185 | */ |
186 | if (ftrace_list == ops && ops->next == &ftrace_list_end) { | |
187 | ftrace_trace_function = ftrace_stub; | |
188 | ftrace_list = &ftrace_list_end; | |
e6ea44e9 | 189 | return 0; |
16444a8a ACM |
190 | } |
191 | ||
192 | for (p = &ftrace_list; *p != &ftrace_list_end; p = &(*p)->next) | |
193 | if (*p == ops) | |
194 | break; | |
195 | ||
e6ea44e9 SR |
196 | if (*p != ops) |
197 | return -1; | |
16444a8a ACM |
198 | |
199 | *p = (*p)->next; | |
200 | ||
b0fc494f SR |
201 | if (ftrace_enabled) { |
202 | /* If we only have one func left, then call that directly */ | |
df4fc315 SR |
203 | if (ftrace_list->next == &ftrace_list_end) { |
204 | ftrace_func_t func = ftrace_list->func; | |
205 | ||
978f3a45 | 206 | if (ftrace_pid_trace) { |
df4fc315 SR |
207 | set_ftrace_pid_function(func); |
208 | func = ftrace_pid_func; | |
209 | } | |
210 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST | |
211 | ftrace_trace_function = func; | |
212 | #else | |
213 | __ftrace_trace_function = func; | |
214 | #endif | |
215 | } | |
b0fc494f | 216 | } |
16444a8a | 217 | |
e6ea44e9 | 218 | return 0; |
3d083395 SR |
219 | } |
220 | ||
df4fc315 SR |
221 | static void ftrace_update_pid_func(void) |
222 | { | |
223 | ftrace_func_t func; | |
224 | ||
df4fc315 | 225 | if (ftrace_trace_function == ftrace_stub) |
10dd3ebe | 226 | return; |
df4fc315 SR |
227 | |
228 | func = ftrace_trace_function; | |
229 | ||
978f3a45 | 230 | if (ftrace_pid_trace) { |
df4fc315 SR |
231 | set_ftrace_pid_function(func); |
232 | func = ftrace_pid_func; | |
233 | } else { | |
66eafebc LW |
234 | if (func == ftrace_pid_func) |
235 | func = ftrace_pid_function; | |
df4fc315 SR |
236 | } |
237 | ||
238 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST | |
239 | ftrace_trace_function = func; | |
240 | #else | |
241 | __ftrace_trace_function = func; | |
242 | #endif | |
df4fc315 SR |
243 | } |
244 | ||
493762fc SR |
245 | #ifdef CONFIG_FUNCTION_PROFILER |
246 | struct ftrace_profile { | |
247 | struct hlist_node node; | |
248 | unsigned long ip; | |
249 | unsigned long counter; | |
0706f1c4 SR |
250 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
251 | unsigned long long time; | |
252 | #endif | |
8fc0c701 SR |
253 | }; |
254 | ||
493762fc SR |
255 | struct ftrace_profile_page { |
256 | struct ftrace_profile_page *next; | |
257 | unsigned long index; | |
258 | struct ftrace_profile records[]; | |
d61f82d0 SR |
259 | }; |
260 | ||
cafb168a SR |
261 | struct ftrace_profile_stat { |
262 | atomic_t disabled; | |
263 | struct hlist_head *hash; | |
264 | struct ftrace_profile_page *pages; | |
265 | struct ftrace_profile_page *start; | |
266 | struct tracer_stat stat; | |
267 | }; | |
268 | ||
493762fc SR |
269 | #define PROFILE_RECORDS_SIZE \ |
270 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | |
5072c59f | 271 | |
493762fc SR |
272 | #define PROFILES_PER_PAGE \ |
273 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | |
3d083395 | 274 | |
fb9fb015 SR |
275 | static int ftrace_profile_bits __read_mostly; |
276 | static int ftrace_profile_enabled __read_mostly; | |
277 | ||
278 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ | |
bac429f0 SR |
279 | static DEFINE_MUTEX(ftrace_profile_lock); |
280 | ||
cafb168a | 281 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); |
493762fc SR |
282 | |
283 | #define FTRACE_PROFILE_HASH_SIZE 1024 /* must be power of 2 */ | |
284 | ||
bac429f0 SR |
285 | static void * |
286 | function_stat_next(void *v, int idx) | |
287 | { | |
493762fc SR |
288 | struct ftrace_profile *rec = v; |
289 | struct ftrace_profile_page *pg; | |
bac429f0 | 290 | |
493762fc | 291 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
bac429f0 SR |
292 | |
293 | again: | |
294 | rec++; | |
295 | if ((void *)rec >= (void *)&pg->records[pg->index]) { | |
296 | pg = pg->next; | |
297 | if (!pg) | |
298 | return NULL; | |
299 | rec = &pg->records[0]; | |
493762fc SR |
300 | if (!rec->counter) |
301 | goto again; | |
bac429f0 SR |
302 | } |
303 | ||
bac429f0 SR |
304 | return rec; |
305 | } | |
306 | ||
307 | static void *function_stat_start(struct tracer_stat *trace) | |
308 | { | |
cafb168a SR |
309 | struct ftrace_profile_stat *stat = |
310 | container_of(trace, struct ftrace_profile_stat, stat); | |
311 | ||
312 | if (!stat || !stat->start) | |
313 | return NULL; | |
314 | ||
315 | return function_stat_next(&stat->start->records[0], 0); | |
bac429f0 SR |
316 | } |
317 | ||
0706f1c4 SR |
318 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
319 | /* function graph compares on total time */ | |
320 | static int function_stat_cmp(void *p1, void *p2) | |
321 | { | |
322 | struct ftrace_profile *a = p1; | |
323 | struct ftrace_profile *b = p2; | |
324 | ||
325 | if (a->time < b->time) | |
326 | return -1; | |
327 | if (a->time > b->time) | |
328 | return 1; | |
329 | else | |
330 | return 0; | |
331 | } | |
332 | #else | |
333 | /* not function graph compares against hits */ | |
bac429f0 SR |
334 | static int function_stat_cmp(void *p1, void *p2) |
335 | { | |
493762fc SR |
336 | struct ftrace_profile *a = p1; |
337 | struct ftrace_profile *b = p2; | |
bac429f0 SR |
338 | |
339 | if (a->counter < b->counter) | |
340 | return -1; | |
341 | if (a->counter > b->counter) | |
342 | return 1; | |
343 | else | |
344 | return 0; | |
345 | } | |
0706f1c4 | 346 | #endif |
bac429f0 SR |
347 | |
348 | static int function_stat_headers(struct seq_file *m) | |
349 | { | |
0706f1c4 | 350 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b SR |
351 | seq_printf(m, " Function " |
352 | "Hit Time Avg\n" | |
353 | " -------- " | |
354 | "--- ---- ---\n"); | |
0706f1c4 | 355 | #else |
bac429f0 SR |
356 | seq_printf(m, " Function Hit\n" |
357 | " -------- ---\n"); | |
0706f1c4 | 358 | #endif |
bac429f0 SR |
359 | return 0; |
360 | } | |
361 | ||
362 | static int function_stat_show(struct seq_file *m, void *v) | |
363 | { | |
493762fc | 364 | struct ftrace_profile *rec = v; |
bac429f0 | 365 | char str[KSYM_SYMBOL_LEN]; |
0706f1c4 | 366 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
0706f1c4 | 367 | static DEFINE_MUTEX(mutex); |
34886c8b SR |
368 | static struct trace_seq s; |
369 | unsigned long long avg; | |
0706f1c4 | 370 | #endif |
bac429f0 SR |
371 | |
372 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
0706f1c4 SR |
373 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); |
374 | ||
375 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
376 | seq_printf(m, " "); | |
34886c8b SR |
377 | avg = rec->time; |
378 | do_div(avg, rec->counter); | |
379 | ||
380 | mutex_lock(&mutex); | |
381 | trace_seq_init(&s); | |
382 | trace_print_graph_duration(rec->time, &s); | |
383 | trace_seq_puts(&s, " "); | |
384 | trace_print_graph_duration(avg, &s); | |
0706f1c4 SR |
385 | trace_print_seq(m, &s); |
386 | mutex_unlock(&mutex); | |
387 | #endif | |
388 | seq_putc(m, '\n'); | |
bac429f0 | 389 | |
bac429f0 SR |
390 | return 0; |
391 | } | |
392 | ||
cafb168a | 393 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) |
bac429f0 | 394 | { |
493762fc | 395 | struct ftrace_profile_page *pg; |
bac429f0 | 396 | |
cafb168a | 397 | pg = stat->pages = stat->start; |
bac429f0 | 398 | |
493762fc SR |
399 | while (pg) { |
400 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | |
401 | pg->index = 0; | |
402 | pg = pg->next; | |
bac429f0 SR |
403 | } |
404 | ||
cafb168a | 405 | memset(stat->hash, 0, |
493762fc SR |
406 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); |
407 | } | |
bac429f0 | 408 | |
cafb168a | 409 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) |
493762fc SR |
410 | { |
411 | struct ftrace_profile_page *pg; | |
318e0a73 SR |
412 | int functions; |
413 | int pages; | |
493762fc | 414 | int i; |
bac429f0 | 415 | |
493762fc | 416 | /* If we already allocated, do nothing */ |
cafb168a | 417 | if (stat->pages) |
493762fc | 418 | return 0; |
bac429f0 | 419 | |
cafb168a SR |
420 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); |
421 | if (!stat->pages) | |
493762fc | 422 | return -ENOMEM; |
bac429f0 | 423 | |
318e0a73 SR |
424 | #ifdef CONFIG_DYNAMIC_FTRACE |
425 | functions = ftrace_update_tot_cnt; | |
426 | #else | |
427 | /* | |
428 | * We do not know the number of functions that exist because | |
429 | * dynamic tracing is what counts them. With past experience | |
430 | * we have around 20K functions. That should be more than enough. | |
431 | * It is highly unlikely we will execute every function in | |
432 | * the kernel. | |
433 | */ | |
434 | functions = 20000; | |
435 | #endif | |
436 | ||
cafb168a | 437 | pg = stat->start = stat->pages; |
bac429f0 | 438 | |
318e0a73 SR |
439 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); |
440 | ||
441 | for (i = 0; i < pages; i++) { | |
493762fc | 442 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
493762fc | 443 | if (!pg->next) |
318e0a73 | 444 | goto out_free; |
493762fc SR |
445 | pg = pg->next; |
446 | } | |
447 | ||
448 | return 0; | |
318e0a73 SR |
449 | |
450 | out_free: | |
451 | pg = stat->start; | |
452 | while (pg) { | |
453 | unsigned long tmp = (unsigned long)pg; | |
454 | ||
455 | pg = pg->next; | |
456 | free_page(tmp); | |
457 | } | |
458 | ||
459 | free_page((unsigned long)stat->pages); | |
460 | stat->pages = NULL; | |
461 | stat->start = NULL; | |
462 | ||
463 | return -ENOMEM; | |
bac429f0 SR |
464 | } |
465 | ||
cafb168a | 466 | static int ftrace_profile_init_cpu(int cpu) |
bac429f0 | 467 | { |
cafb168a | 468 | struct ftrace_profile_stat *stat; |
493762fc | 469 | int size; |
bac429f0 | 470 | |
cafb168a SR |
471 | stat = &per_cpu(ftrace_profile_stats, cpu); |
472 | ||
473 | if (stat->hash) { | |
493762fc | 474 | /* If the profile is already created, simply reset it */ |
cafb168a | 475 | ftrace_profile_reset(stat); |
493762fc SR |
476 | return 0; |
477 | } | |
bac429f0 | 478 | |
493762fc SR |
479 | /* |
480 | * We are profiling all functions, but usually only a few thousand | |
481 | * functions are hit. We'll make a hash of 1024 items. | |
482 | */ | |
483 | size = FTRACE_PROFILE_HASH_SIZE; | |
bac429f0 | 484 | |
cafb168a | 485 | stat->hash = kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL); |
493762fc | 486 | |
cafb168a | 487 | if (!stat->hash) |
493762fc SR |
488 | return -ENOMEM; |
489 | ||
cafb168a SR |
490 | if (!ftrace_profile_bits) { |
491 | size--; | |
493762fc | 492 | |
cafb168a SR |
493 | for (; size; size >>= 1) |
494 | ftrace_profile_bits++; | |
495 | } | |
493762fc | 496 | |
318e0a73 | 497 | /* Preallocate the function profiling pages */ |
cafb168a SR |
498 | if (ftrace_profile_pages_init(stat) < 0) { |
499 | kfree(stat->hash); | |
500 | stat->hash = NULL; | |
493762fc SR |
501 | return -ENOMEM; |
502 | } | |
503 | ||
504 | return 0; | |
bac429f0 SR |
505 | } |
506 | ||
cafb168a SR |
507 | static int ftrace_profile_init(void) |
508 | { | |
509 | int cpu; | |
510 | int ret = 0; | |
511 | ||
512 | for_each_online_cpu(cpu) { | |
513 | ret = ftrace_profile_init_cpu(cpu); | |
514 | if (ret) | |
515 | break; | |
516 | } | |
517 | ||
518 | return ret; | |
519 | } | |
520 | ||
493762fc | 521 | /* interrupts must be disabled */ |
cafb168a SR |
522 | static struct ftrace_profile * |
523 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) | |
bac429f0 | 524 | { |
493762fc | 525 | struct ftrace_profile *rec; |
bac429f0 SR |
526 | struct hlist_head *hhd; |
527 | struct hlist_node *n; | |
bac429f0 SR |
528 | unsigned long key; |
529 | ||
bac429f0 | 530 | key = hash_long(ip, ftrace_profile_bits); |
cafb168a | 531 | hhd = &stat->hash[key]; |
bac429f0 SR |
532 | |
533 | if (hlist_empty(hhd)) | |
534 | return NULL; | |
535 | ||
bac429f0 SR |
536 | hlist_for_each_entry_rcu(rec, n, hhd, node) { |
537 | if (rec->ip == ip) | |
493762fc SR |
538 | return rec; |
539 | } | |
540 | ||
541 | return NULL; | |
542 | } | |
543 | ||
cafb168a SR |
544 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, |
545 | struct ftrace_profile *rec) | |
493762fc SR |
546 | { |
547 | unsigned long key; | |
548 | ||
549 | key = hash_long(rec->ip, ftrace_profile_bits); | |
cafb168a | 550 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); |
493762fc SR |
551 | } |
552 | ||
318e0a73 SR |
553 | /* |
554 | * The memory is already allocated, this simply finds a new record to use. | |
555 | */ | |
493762fc | 556 | static struct ftrace_profile * |
318e0a73 | 557 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) |
493762fc SR |
558 | { |
559 | struct ftrace_profile *rec = NULL; | |
560 | ||
318e0a73 | 561 | /* prevent recursion (from NMIs) */ |
cafb168a | 562 | if (atomic_inc_return(&stat->disabled) != 1) |
493762fc SR |
563 | goto out; |
564 | ||
493762fc | 565 | /* |
318e0a73 SR |
566 | * Try to find the function again since an NMI |
567 | * could have added it | |
493762fc | 568 | */ |
cafb168a | 569 | rec = ftrace_find_profiled_func(stat, ip); |
493762fc | 570 | if (rec) |
cafb168a | 571 | goto out; |
493762fc | 572 | |
cafb168a SR |
573 | if (stat->pages->index == PROFILES_PER_PAGE) { |
574 | if (!stat->pages->next) | |
575 | goto out; | |
576 | stat->pages = stat->pages->next; | |
bac429f0 | 577 | } |
493762fc | 578 | |
cafb168a | 579 | rec = &stat->pages->records[stat->pages->index++]; |
493762fc | 580 | rec->ip = ip; |
cafb168a | 581 | ftrace_add_profile(stat, rec); |
493762fc | 582 | |
bac429f0 | 583 | out: |
cafb168a | 584 | atomic_dec(&stat->disabled); |
bac429f0 SR |
585 | |
586 | return rec; | |
587 | } | |
588 | ||
589 | static void | |
590 | function_profile_call(unsigned long ip, unsigned long parent_ip) | |
591 | { | |
cafb168a | 592 | struct ftrace_profile_stat *stat; |
493762fc | 593 | struct ftrace_profile *rec; |
bac429f0 SR |
594 | unsigned long flags; |
595 | ||
596 | if (!ftrace_profile_enabled) | |
597 | return; | |
598 | ||
599 | local_irq_save(flags); | |
cafb168a SR |
600 | |
601 | stat = &__get_cpu_var(ftrace_profile_stats); | |
602 | if (!stat->hash) | |
603 | goto out; | |
604 | ||
605 | rec = ftrace_find_profiled_func(stat, ip); | |
493762fc | 606 | if (!rec) { |
318e0a73 | 607 | rec = ftrace_profile_alloc(stat, ip); |
493762fc SR |
608 | if (!rec) |
609 | goto out; | |
610 | } | |
bac429f0 SR |
611 | |
612 | rec->counter++; | |
613 | out: | |
614 | local_irq_restore(flags); | |
615 | } | |
616 | ||
0706f1c4 SR |
617 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
618 | static int profile_graph_entry(struct ftrace_graph_ent *trace) | |
619 | { | |
620 | function_profile_call(trace->func, 0); | |
621 | return 1; | |
622 | } | |
623 | ||
624 | static void profile_graph_return(struct ftrace_graph_ret *trace) | |
625 | { | |
cafb168a | 626 | struct ftrace_profile_stat *stat; |
a2a16d6a | 627 | unsigned long long calltime; |
0706f1c4 | 628 | struct ftrace_profile *rec; |
cafb168a | 629 | unsigned long flags; |
0706f1c4 SR |
630 | |
631 | local_irq_save(flags); | |
cafb168a SR |
632 | stat = &__get_cpu_var(ftrace_profile_stats); |
633 | if (!stat->hash) | |
634 | goto out; | |
635 | ||
a2a16d6a SR |
636 | calltime = trace->rettime - trace->calltime; |
637 | ||
638 | if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) { | |
639 | int index; | |
640 | ||
641 | index = trace->depth; | |
642 | ||
643 | /* Append this call time to the parent time to subtract */ | |
644 | if (index) | |
645 | current->ret_stack[index - 1].subtime += calltime; | |
646 | ||
647 | if (current->ret_stack[index].subtime < calltime) | |
648 | calltime -= current->ret_stack[index].subtime; | |
649 | else | |
650 | calltime = 0; | |
651 | } | |
652 | ||
cafb168a | 653 | rec = ftrace_find_profiled_func(stat, trace->func); |
0706f1c4 | 654 | if (rec) |
a2a16d6a SR |
655 | rec->time += calltime; |
656 | ||
cafb168a | 657 | out: |
0706f1c4 SR |
658 | local_irq_restore(flags); |
659 | } | |
660 | ||
661 | static int register_ftrace_profiler(void) | |
662 | { | |
663 | return register_ftrace_graph(&profile_graph_return, | |
664 | &profile_graph_entry); | |
665 | } | |
666 | ||
667 | static void unregister_ftrace_profiler(void) | |
668 | { | |
669 | unregister_ftrace_graph(); | |
670 | } | |
671 | #else | |
bac429f0 SR |
672 | static struct ftrace_ops ftrace_profile_ops __read_mostly = |
673 | { | |
fb9fb015 | 674 | .func = function_profile_call, |
bac429f0 SR |
675 | }; |
676 | ||
0706f1c4 SR |
677 | static int register_ftrace_profiler(void) |
678 | { | |
679 | return register_ftrace_function(&ftrace_profile_ops); | |
680 | } | |
681 | ||
682 | static void unregister_ftrace_profiler(void) | |
683 | { | |
684 | unregister_ftrace_function(&ftrace_profile_ops); | |
685 | } | |
686 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
687 | ||
bac429f0 SR |
688 | static ssize_t |
689 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | |
690 | size_t cnt, loff_t *ppos) | |
691 | { | |
692 | unsigned long val; | |
fb9fb015 | 693 | char buf[64]; /* big enough to hold a number */ |
bac429f0 SR |
694 | int ret; |
695 | ||
bac429f0 SR |
696 | if (cnt >= sizeof(buf)) |
697 | return -EINVAL; | |
698 | ||
699 | if (copy_from_user(&buf, ubuf, cnt)) | |
700 | return -EFAULT; | |
701 | ||
702 | buf[cnt] = 0; | |
703 | ||
704 | ret = strict_strtoul(buf, 10, &val); | |
705 | if (ret < 0) | |
706 | return ret; | |
707 | ||
708 | val = !!val; | |
709 | ||
710 | mutex_lock(&ftrace_profile_lock); | |
711 | if (ftrace_profile_enabled ^ val) { | |
712 | if (val) { | |
493762fc SR |
713 | ret = ftrace_profile_init(); |
714 | if (ret < 0) { | |
715 | cnt = ret; | |
716 | goto out; | |
717 | } | |
718 | ||
0706f1c4 SR |
719 | ret = register_ftrace_profiler(); |
720 | if (ret < 0) { | |
721 | cnt = ret; | |
722 | goto out; | |
723 | } | |
bac429f0 SR |
724 | ftrace_profile_enabled = 1; |
725 | } else { | |
726 | ftrace_profile_enabled = 0; | |
0706f1c4 | 727 | unregister_ftrace_profiler(); |
bac429f0 SR |
728 | } |
729 | } | |
493762fc | 730 | out: |
bac429f0 SR |
731 | mutex_unlock(&ftrace_profile_lock); |
732 | ||
733 | filp->f_pos += cnt; | |
734 | ||
735 | return cnt; | |
736 | } | |
737 | ||
493762fc SR |
738 | static ssize_t |
739 | ftrace_profile_read(struct file *filp, char __user *ubuf, | |
740 | size_t cnt, loff_t *ppos) | |
741 | { | |
fb9fb015 | 742 | char buf[64]; /* big enough to hold a number */ |
493762fc SR |
743 | int r; |
744 | ||
745 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | |
746 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
747 | } | |
748 | ||
bac429f0 SR |
749 | static const struct file_operations ftrace_profile_fops = { |
750 | .open = tracing_open_generic, | |
751 | .read = ftrace_profile_read, | |
752 | .write = ftrace_profile_write, | |
753 | }; | |
754 | ||
cafb168a SR |
755 | /* used to initialize the real stat files */ |
756 | static struct tracer_stat function_stats __initdata = { | |
fb9fb015 SR |
757 | .name = "functions", |
758 | .stat_start = function_stat_start, | |
759 | .stat_next = function_stat_next, | |
760 | .stat_cmp = function_stat_cmp, | |
761 | .stat_headers = function_stat_headers, | |
762 | .stat_show = function_stat_show | |
cafb168a SR |
763 | }; |
764 | ||
bac429f0 SR |
765 | static void ftrace_profile_debugfs(struct dentry *d_tracer) |
766 | { | |
cafb168a | 767 | struct ftrace_profile_stat *stat; |
bac429f0 | 768 | struct dentry *entry; |
cafb168a | 769 | char *name; |
bac429f0 | 770 | int ret; |
cafb168a SR |
771 | int cpu; |
772 | ||
773 | for_each_possible_cpu(cpu) { | |
774 | stat = &per_cpu(ftrace_profile_stats, cpu); | |
775 | ||
776 | /* allocate enough for function name + cpu number */ | |
777 | name = kmalloc(32, GFP_KERNEL); | |
778 | if (!name) { | |
779 | /* | |
780 | * The files created are permanent, if something happens | |
781 | * we still do not free memory. | |
782 | */ | |
783 | kfree(stat); | |
784 | WARN(1, | |
785 | "Could not allocate stat file for cpu %d\n", | |
786 | cpu); | |
787 | return; | |
788 | } | |
789 | stat->stat = function_stats; | |
790 | snprintf(name, 32, "function%d", cpu); | |
791 | stat->stat.name = name; | |
792 | ret = register_stat_tracer(&stat->stat); | |
793 | if (ret) { | |
794 | WARN(1, | |
795 | "Could not register function stat for cpu %d\n", | |
796 | cpu); | |
797 | kfree(name); | |
798 | return; | |
799 | } | |
bac429f0 SR |
800 | } |
801 | ||
802 | entry = debugfs_create_file("function_profile_enabled", 0644, | |
803 | d_tracer, NULL, &ftrace_profile_fops); | |
804 | if (!entry) | |
805 | pr_warning("Could not create debugfs " | |
806 | "'function_profile_enabled' entry\n"); | |
807 | } | |
808 | ||
bac429f0 | 809 | #else /* CONFIG_FUNCTION_PROFILER */ |
bac429f0 SR |
810 | static void ftrace_profile_debugfs(struct dentry *d_tracer) |
811 | { | |
812 | } | |
bac429f0 SR |
813 | #endif /* CONFIG_FUNCTION_PROFILER */ |
814 | ||
493762fc SR |
815 | /* set when tracing only a pid */ |
816 | struct pid *ftrace_pid_trace; | |
817 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; | |
818 | ||
819 | #ifdef CONFIG_DYNAMIC_FTRACE | |
820 | ||
821 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD | |
822 | # error Dynamic ftrace depends on MCOUNT_RECORD | |
823 | #endif | |
824 | ||
825 | static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly; | |
826 | ||
827 | struct ftrace_func_probe { | |
828 | struct hlist_node node; | |
829 | struct ftrace_probe_ops *ops; | |
830 | unsigned long flags; | |
831 | unsigned long ip; | |
832 | void *data; | |
833 | struct rcu_head rcu; | |
834 | }; | |
835 | ||
836 | enum { | |
837 | FTRACE_ENABLE_CALLS = (1 << 0), | |
838 | FTRACE_DISABLE_CALLS = (1 << 1), | |
839 | FTRACE_UPDATE_TRACE_FUNC = (1 << 2), | |
840 | FTRACE_ENABLE_MCOUNT = (1 << 3), | |
841 | FTRACE_DISABLE_MCOUNT = (1 << 4), | |
842 | FTRACE_START_FUNC_RET = (1 << 5), | |
843 | FTRACE_STOP_FUNC_RET = (1 << 6), | |
844 | }; | |
845 | ||
846 | static int ftrace_filtered; | |
847 | ||
848 | static struct dyn_ftrace *ftrace_new_addrs; | |
849 | ||
850 | static DEFINE_MUTEX(ftrace_regex_lock); | |
851 | ||
852 | struct ftrace_page { | |
853 | struct ftrace_page *next; | |
854 | int index; | |
855 | struct dyn_ftrace records[]; | |
856 | }; | |
857 | ||
858 | #define ENTRIES_PER_PAGE \ | |
859 | ((PAGE_SIZE - sizeof(struct ftrace_page)) / sizeof(struct dyn_ftrace)) | |
860 | ||
861 | /* estimate from running different kernels */ | |
862 | #define NR_TO_INIT 10000 | |
863 | ||
864 | static struct ftrace_page *ftrace_pages_start; | |
865 | static struct ftrace_page *ftrace_pages; | |
866 | ||
867 | static struct dyn_ftrace *ftrace_free_records; | |
868 | ||
869 | /* | |
870 | * This is a double for. Do not use 'break' to break out of the loop, | |
871 | * you must use a goto. | |
872 | */ | |
873 | #define do_for_each_ftrace_rec(pg, rec) \ | |
874 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
875 | int _____i; \ | |
876 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
877 | rec = &pg->records[_____i]; | |
878 | ||
879 | #define while_for_each_ftrace_rec() \ | |
880 | } \ | |
881 | } | |
882 | ||
ecea656d | 883 | #ifdef CONFIG_KPROBES |
f17845e5 IM |
884 | |
885 | static int frozen_record_count; | |
886 | ||
ecea656d AS |
887 | static inline void freeze_record(struct dyn_ftrace *rec) |
888 | { | |
889 | if (!(rec->flags & FTRACE_FL_FROZEN)) { | |
890 | rec->flags |= FTRACE_FL_FROZEN; | |
891 | frozen_record_count++; | |
892 | } | |
893 | } | |
894 | ||
895 | static inline void unfreeze_record(struct dyn_ftrace *rec) | |
896 | { | |
897 | if (rec->flags & FTRACE_FL_FROZEN) { | |
898 | rec->flags &= ~FTRACE_FL_FROZEN; | |
899 | frozen_record_count--; | |
900 | } | |
901 | } | |
902 | ||
903 | static inline int record_frozen(struct dyn_ftrace *rec) | |
904 | { | |
905 | return rec->flags & FTRACE_FL_FROZEN; | |
906 | } | |
907 | #else | |
908 | # define freeze_record(rec) ({ 0; }) | |
909 | # define unfreeze_record(rec) ({ 0; }) | |
910 | # define record_frozen(rec) ({ 0; }) | |
911 | #endif /* CONFIG_KPROBES */ | |
912 | ||
e309b41d | 913 | static void ftrace_free_rec(struct dyn_ftrace *rec) |
37ad5084 | 914 | { |
ee000b7f | 915 | rec->freelist = ftrace_free_records; |
37ad5084 SR |
916 | ftrace_free_records = rec; |
917 | rec->flags |= FTRACE_FL_FREE; | |
918 | } | |
919 | ||
e309b41d | 920 | static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip) |
3c1720f0 | 921 | { |
37ad5084 SR |
922 | struct dyn_ftrace *rec; |
923 | ||
924 | /* First check for freed records */ | |
925 | if (ftrace_free_records) { | |
926 | rec = ftrace_free_records; | |
927 | ||
37ad5084 | 928 | if (unlikely(!(rec->flags & FTRACE_FL_FREE))) { |
6912896e | 929 | FTRACE_WARN_ON_ONCE(1); |
37ad5084 SR |
930 | ftrace_free_records = NULL; |
931 | return NULL; | |
932 | } | |
933 | ||
ee000b7f | 934 | ftrace_free_records = rec->freelist; |
37ad5084 SR |
935 | memset(rec, 0, sizeof(*rec)); |
936 | return rec; | |
937 | } | |
938 | ||
3c1720f0 | 939 | if (ftrace_pages->index == ENTRIES_PER_PAGE) { |
08f5ac90 SR |
940 | if (!ftrace_pages->next) { |
941 | /* allocate another page */ | |
942 | ftrace_pages->next = | |
943 | (void *)get_zeroed_page(GFP_KERNEL); | |
944 | if (!ftrace_pages->next) | |
945 | return NULL; | |
946 | } | |
3c1720f0 SR |
947 | ftrace_pages = ftrace_pages->next; |
948 | } | |
949 | ||
950 | return &ftrace_pages->records[ftrace_pages->index++]; | |
951 | } | |
952 | ||
08f5ac90 | 953 | static struct dyn_ftrace * |
d61f82d0 | 954 | ftrace_record_ip(unsigned long ip) |
3d083395 | 955 | { |
08f5ac90 | 956 | struct dyn_ftrace *rec; |
3d083395 | 957 | |
f3c7ac40 | 958 | if (ftrace_disabled) |
08f5ac90 | 959 | return NULL; |
3d083395 | 960 | |
08f5ac90 SR |
961 | rec = ftrace_alloc_dyn_node(ip); |
962 | if (!rec) | |
963 | return NULL; | |
3d083395 | 964 | |
08f5ac90 | 965 | rec->ip = ip; |
ee000b7f | 966 | rec->newlist = ftrace_new_addrs; |
e94142a6 | 967 | ftrace_new_addrs = rec; |
3d083395 | 968 | |
08f5ac90 | 969 | return rec; |
3d083395 SR |
970 | } |
971 | ||
b17e8a37 SR |
972 | static void print_ip_ins(const char *fmt, unsigned char *p) |
973 | { | |
974 | int i; | |
975 | ||
976 | printk(KERN_CONT "%s", fmt); | |
977 | ||
978 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
979 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
980 | } | |
981 | ||
31e88909 | 982 | static void ftrace_bug(int failed, unsigned long ip) |
b17e8a37 SR |
983 | { |
984 | switch (failed) { | |
985 | case -EFAULT: | |
986 | FTRACE_WARN_ON_ONCE(1); | |
987 | pr_info("ftrace faulted on modifying "); | |
988 | print_ip_sym(ip); | |
989 | break; | |
990 | case -EINVAL: | |
991 | FTRACE_WARN_ON_ONCE(1); | |
992 | pr_info("ftrace failed to modify "); | |
993 | print_ip_sym(ip); | |
b17e8a37 | 994 | print_ip_ins(" actual: ", (unsigned char *)ip); |
b17e8a37 SR |
995 | printk(KERN_CONT "\n"); |
996 | break; | |
997 | case -EPERM: | |
998 | FTRACE_WARN_ON_ONCE(1); | |
999 | pr_info("ftrace faulted on writing "); | |
1000 | print_ip_sym(ip); | |
1001 | break; | |
1002 | default: | |
1003 | FTRACE_WARN_ON_ONCE(1); | |
1004 | pr_info("ftrace faulted on unknown error "); | |
1005 | print_ip_sym(ip); | |
1006 | } | |
1007 | } | |
1008 | ||
3c1720f0 | 1009 | |
0eb96701 | 1010 | static int |
31e88909 | 1011 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) |
5072c59f | 1012 | { |
e7d3737e | 1013 | unsigned long ftrace_addr; |
6a24a244 | 1014 | unsigned long ip, fl; |
e7d3737e | 1015 | |
f0001207 | 1016 | ftrace_addr = (unsigned long)FTRACE_ADDR; |
5072c59f SR |
1017 | |
1018 | ip = rec->ip; | |
1019 | ||
982c350b SR |
1020 | /* |
1021 | * If this record is not to be traced and | |
1022 | * it is not enabled then do nothing. | |
1023 | * | |
1024 | * If this record is not to be traced and | |
57794a9d | 1025 | * it is enabled then disable it. |
982c350b SR |
1026 | * |
1027 | */ | |
1028 | if (rec->flags & FTRACE_FL_NOTRACE) { | |
1029 | if (rec->flags & FTRACE_FL_ENABLED) | |
1030 | rec->flags &= ~FTRACE_FL_ENABLED; | |
1031 | else | |
1032 | return 0; | |
1033 | ||
1034 | } else if (ftrace_filtered && enable) { | |
5072c59f | 1035 | /* |
982c350b | 1036 | * Filtering is on: |
5072c59f | 1037 | */ |
a4500b84 | 1038 | |
982c350b | 1039 | fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED); |
5072c59f | 1040 | |
982c350b SR |
1041 | /* Record is filtered and enabled, do nothing */ |
1042 | if (fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED)) | |
0eb96701 | 1043 | return 0; |
5072c59f | 1044 | |
57794a9d | 1045 | /* Record is not filtered or enabled, do nothing */ |
982c350b SR |
1046 | if (!fl) |
1047 | return 0; | |
1048 | ||
1049 | /* Record is not filtered but enabled, disable it */ | |
1050 | if (fl == FTRACE_FL_ENABLED) | |
5072c59f | 1051 | rec->flags &= ~FTRACE_FL_ENABLED; |
982c350b SR |
1052 | else |
1053 | /* Otherwise record is filtered but not enabled, enable it */ | |
5072c59f | 1054 | rec->flags |= FTRACE_FL_ENABLED; |
5072c59f | 1055 | } else { |
982c350b | 1056 | /* Disable or not filtered */ |
5072c59f | 1057 | |
41c52c0d | 1058 | if (enable) { |
982c350b | 1059 | /* if record is enabled, do nothing */ |
5072c59f | 1060 | if (rec->flags & FTRACE_FL_ENABLED) |
0eb96701 | 1061 | return 0; |
982c350b | 1062 | |
5072c59f | 1063 | rec->flags |= FTRACE_FL_ENABLED; |
982c350b | 1064 | |
5072c59f | 1065 | } else { |
982c350b | 1066 | |
57794a9d | 1067 | /* if record is not enabled, do nothing */ |
5072c59f | 1068 | if (!(rec->flags & FTRACE_FL_ENABLED)) |
0eb96701 | 1069 | return 0; |
982c350b | 1070 | |
5072c59f SR |
1071 | rec->flags &= ~FTRACE_FL_ENABLED; |
1072 | } | |
1073 | } | |
1074 | ||
982c350b | 1075 | if (rec->flags & FTRACE_FL_ENABLED) |
e7d3737e | 1076 | return ftrace_make_call(rec, ftrace_addr); |
31e88909 | 1077 | else |
e7d3737e | 1078 | return ftrace_make_nop(NULL, rec, ftrace_addr); |
5072c59f SR |
1079 | } |
1080 | ||
e309b41d | 1081 | static void ftrace_replace_code(int enable) |
3c1720f0 | 1082 | { |
3c1720f0 SR |
1083 | struct dyn_ftrace *rec; |
1084 | struct ftrace_page *pg; | |
6a24a244 | 1085 | int failed; |
3c1720f0 | 1086 | |
265c831c SR |
1087 | do_for_each_ftrace_rec(pg, rec) { |
1088 | /* | |
fa9d13cf Z |
1089 | * Skip over free records, records that have |
1090 | * failed and not converted. | |
265c831c SR |
1091 | */ |
1092 | if (rec->flags & FTRACE_FL_FREE || | |
fa9d13cf | 1093 | rec->flags & FTRACE_FL_FAILED || |
03303549 | 1094 | !(rec->flags & FTRACE_FL_CONVERTED)) |
265c831c SR |
1095 | continue; |
1096 | ||
1097 | /* ignore updates to this record's mcount site */ | |
1098 | if (get_kprobe((void *)rec->ip)) { | |
1099 | freeze_record(rec); | |
1100 | continue; | |
1101 | } else { | |
1102 | unfreeze_record(rec); | |
1103 | } | |
f22f9a89 | 1104 | |
265c831c | 1105 | failed = __ftrace_replace_code(rec, enable); |
fa9d13cf | 1106 | if (failed) { |
265c831c SR |
1107 | rec->flags |= FTRACE_FL_FAILED; |
1108 | if ((system_state == SYSTEM_BOOTING) || | |
1109 | !core_kernel_text(rec->ip)) { | |
1110 | ftrace_free_rec(rec); | |
4377245a | 1111 | } else { |
265c831c | 1112 | ftrace_bug(failed, rec->ip); |
4377245a SR |
1113 | /* Stop processing */ |
1114 | return; | |
1115 | } | |
3c1720f0 | 1116 | } |
265c831c | 1117 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
1118 | } |
1119 | ||
492a7ea5 | 1120 | static int |
31e88909 | 1121 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 SR |
1122 | { |
1123 | unsigned long ip; | |
593eb8a2 | 1124 | int ret; |
3c1720f0 SR |
1125 | |
1126 | ip = rec->ip; | |
1127 | ||
25aac9dc | 1128 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
593eb8a2 | 1129 | if (ret) { |
31e88909 | 1130 | ftrace_bug(ret, ip); |
3c1720f0 | 1131 | rec->flags |= FTRACE_FL_FAILED; |
492a7ea5 | 1132 | return 0; |
37ad5084 | 1133 | } |
492a7ea5 | 1134 | return 1; |
3c1720f0 SR |
1135 | } |
1136 | ||
000ab691 SR |
1137 | /* |
1138 | * archs can override this function if they must do something | |
1139 | * before the modifying code is performed. | |
1140 | */ | |
1141 | int __weak ftrace_arch_code_modify_prepare(void) | |
1142 | { | |
1143 | return 0; | |
1144 | } | |
1145 | ||
1146 | /* | |
1147 | * archs can override this function if they must do something | |
1148 | * after the modifying code is performed. | |
1149 | */ | |
1150 | int __weak ftrace_arch_code_modify_post_process(void) | |
1151 | { | |
1152 | return 0; | |
1153 | } | |
1154 | ||
e309b41d | 1155 | static int __ftrace_modify_code(void *data) |
3d083395 | 1156 | { |
d61f82d0 SR |
1157 | int *command = data; |
1158 | ||
a3583244 | 1159 | if (*command & FTRACE_ENABLE_CALLS) |
d61f82d0 | 1160 | ftrace_replace_code(1); |
a3583244 | 1161 | else if (*command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
1162 | ftrace_replace_code(0); |
1163 | ||
1164 | if (*command & FTRACE_UPDATE_TRACE_FUNC) | |
1165 | ftrace_update_ftrace_func(ftrace_trace_function); | |
1166 | ||
5a45cfe1 SR |
1167 | if (*command & FTRACE_START_FUNC_RET) |
1168 | ftrace_enable_ftrace_graph_caller(); | |
1169 | else if (*command & FTRACE_STOP_FUNC_RET) | |
1170 | ftrace_disable_ftrace_graph_caller(); | |
1171 | ||
d61f82d0 | 1172 | return 0; |
3d083395 SR |
1173 | } |
1174 | ||
e309b41d | 1175 | static void ftrace_run_update_code(int command) |
3d083395 | 1176 | { |
000ab691 SR |
1177 | int ret; |
1178 | ||
1179 | ret = ftrace_arch_code_modify_prepare(); | |
1180 | FTRACE_WARN_ON(ret); | |
1181 | if (ret) | |
1182 | return; | |
1183 | ||
784e2d76 | 1184 | stop_machine(__ftrace_modify_code, &command, NULL); |
000ab691 SR |
1185 | |
1186 | ret = ftrace_arch_code_modify_post_process(); | |
1187 | FTRACE_WARN_ON(ret); | |
3d083395 SR |
1188 | } |
1189 | ||
d61f82d0 | 1190 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 1191 | static int ftrace_start_up; |
df4fc315 SR |
1192 | |
1193 | static void ftrace_startup_enable(int command) | |
1194 | { | |
1195 | if (saved_ftrace_func != ftrace_trace_function) { | |
1196 | saved_ftrace_func = ftrace_trace_function; | |
1197 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
1198 | } | |
1199 | ||
1200 | if (!command || !ftrace_enabled) | |
1201 | return; | |
1202 | ||
1203 | ftrace_run_update_code(command); | |
1204 | } | |
d61f82d0 | 1205 | |
5a45cfe1 | 1206 | static void ftrace_startup(int command) |
3d083395 | 1207 | { |
4eebcc81 SR |
1208 | if (unlikely(ftrace_disabled)) |
1209 | return; | |
1210 | ||
60a7ecf4 | 1211 | ftrace_start_up++; |
982c350b | 1212 | command |= FTRACE_ENABLE_CALLS; |
d61f82d0 | 1213 | |
df4fc315 | 1214 | ftrace_startup_enable(command); |
3d083395 SR |
1215 | } |
1216 | ||
5a45cfe1 | 1217 | static void ftrace_shutdown(int command) |
3d083395 | 1218 | { |
4eebcc81 SR |
1219 | if (unlikely(ftrace_disabled)) |
1220 | return; | |
1221 | ||
60a7ecf4 SR |
1222 | ftrace_start_up--; |
1223 | if (!ftrace_start_up) | |
d61f82d0 | 1224 | command |= FTRACE_DISABLE_CALLS; |
3d083395 | 1225 | |
d61f82d0 SR |
1226 | if (saved_ftrace_func != ftrace_trace_function) { |
1227 | saved_ftrace_func = ftrace_trace_function; | |
1228 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
1229 | } | |
3d083395 | 1230 | |
d61f82d0 | 1231 | if (!command || !ftrace_enabled) |
e6ea44e9 | 1232 | return; |
d61f82d0 SR |
1233 | |
1234 | ftrace_run_update_code(command); | |
3d083395 SR |
1235 | } |
1236 | ||
e309b41d | 1237 | static void ftrace_startup_sysctl(void) |
b0fc494f | 1238 | { |
d61f82d0 SR |
1239 | int command = FTRACE_ENABLE_MCOUNT; |
1240 | ||
4eebcc81 SR |
1241 | if (unlikely(ftrace_disabled)) |
1242 | return; | |
1243 | ||
d61f82d0 SR |
1244 | /* Force update next time */ |
1245 | saved_ftrace_func = NULL; | |
60a7ecf4 SR |
1246 | /* ftrace_start_up is true if we want ftrace running */ |
1247 | if (ftrace_start_up) | |
d61f82d0 SR |
1248 | command |= FTRACE_ENABLE_CALLS; |
1249 | ||
1250 | ftrace_run_update_code(command); | |
b0fc494f SR |
1251 | } |
1252 | ||
e309b41d | 1253 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 1254 | { |
d61f82d0 SR |
1255 | int command = FTRACE_DISABLE_MCOUNT; |
1256 | ||
4eebcc81 SR |
1257 | if (unlikely(ftrace_disabled)) |
1258 | return; | |
1259 | ||
60a7ecf4 SR |
1260 | /* ftrace_start_up is true if ftrace is running */ |
1261 | if (ftrace_start_up) | |
d61f82d0 SR |
1262 | command |= FTRACE_DISABLE_CALLS; |
1263 | ||
1264 | ftrace_run_update_code(command); | |
b0fc494f SR |
1265 | } |
1266 | ||
3d083395 SR |
1267 | static cycle_t ftrace_update_time; |
1268 | static unsigned long ftrace_update_cnt; | |
1269 | unsigned long ftrace_update_tot_cnt; | |
1270 | ||
31e88909 | 1271 | static int ftrace_update_code(struct module *mod) |
3d083395 | 1272 | { |
e94142a6 | 1273 | struct dyn_ftrace *p; |
f22f9a89 | 1274 | cycle_t start, stop; |
3d083395 | 1275 | |
750ed1a4 | 1276 | start = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
1277 | ftrace_update_cnt = 0; |
1278 | ||
e94142a6 | 1279 | while (ftrace_new_addrs) { |
3d083395 | 1280 | |
08f5ac90 SR |
1281 | /* If something went wrong, bail without enabling anything */ |
1282 | if (unlikely(ftrace_disabled)) | |
1283 | return -1; | |
f22f9a89 | 1284 | |
e94142a6 | 1285 | p = ftrace_new_addrs; |
ee000b7f | 1286 | ftrace_new_addrs = p->newlist; |
e94142a6 | 1287 | p->flags = 0L; |
f22f9a89 | 1288 | |
08f5ac90 | 1289 | /* convert record (i.e, patch mcount-call with NOP) */ |
31e88909 | 1290 | if (ftrace_code_disable(mod, p)) { |
08f5ac90 SR |
1291 | p->flags |= FTRACE_FL_CONVERTED; |
1292 | ftrace_update_cnt++; | |
1293 | } else | |
1294 | ftrace_free_rec(p); | |
3d083395 SR |
1295 | } |
1296 | ||
750ed1a4 | 1297 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
1298 | ftrace_update_time = stop - start; |
1299 | ftrace_update_tot_cnt += ftrace_update_cnt; | |
1300 | ||
16444a8a ACM |
1301 | return 0; |
1302 | } | |
1303 | ||
68bf21aa | 1304 | static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) |
3c1720f0 SR |
1305 | { |
1306 | struct ftrace_page *pg; | |
1307 | int cnt; | |
1308 | int i; | |
3c1720f0 SR |
1309 | |
1310 | /* allocate a few pages */ | |
1311 | ftrace_pages_start = (void *)get_zeroed_page(GFP_KERNEL); | |
1312 | if (!ftrace_pages_start) | |
1313 | return -1; | |
1314 | ||
1315 | /* | |
1316 | * Allocate a few more pages. | |
1317 | * | |
1318 | * TODO: have some parser search vmlinux before | |
1319 | * final linking to find all calls to ftrace. | |
1320 | * Then we can: | |
1321 | * a) know how many pages to allocate. | |
1322 | * and/or | |
1323 | * b) set up the table then. | |
1324 | * | |
1325 | * The dynamic code is still necessary for | |
1326 | * modules. | |
1327 | */ | |
1328 | ||
1329 | pg = ftrace_pages = ftrace_pages_start; | |
1330 | ||
68bf21aa | 1331 | cnt = num_to_init / ENTRIES_PER_PAGE; |
08f5ac90 | 1332 | pr_info("ftrace: allocating %ld entries in %d pages\n", |
5821e1b7 | 1333 | num_to_init, cnt + 1); |
3c1720f0 SR |
1334 | |
1335 | for (i = 0; i < cnt; i++) { | |
1336 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); | |
1337 | ||
1338 | /* If we fail, we'll try later anyway */ | |
1339 | if (!pg->next) | |
1340 | break; | |
1341 | ||
1342 | pg = pg->next; | |
1343 | } | |
1344 | ||
1345 | return 0; | |
1346 | } | |
1347 | ||
5072c59f SR |
1348 | enum { |
1349 | FTRACE_ITER_FILTER = (1 << 0), | |
1350 | FTRACE_ITER_CONT = (1 << 1), | |
41c52c0d | 1351 | FTRACE_ITER_NOTRACE = (1 << 2), |
eb9a7bf0 | 1352 | FTRACE_ITER_FAILURES = (1 << 3), |
0c75a3ed | 1353 | FTRACE_ITER_PRINTALL = (1 << 4), |
8fc0c701 | 1354 | FTRACE_ITER_HASH = (1 << 5), |
5072c59f SR |
1355 | }; |
1356 | ||
1357 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ | |
1358 | ||
1359 | struct ftrace_iterator { | |
5072c59f | 1360 | struct ftrace_page *pg; |
8fc0c701 | 1361 | int hidx; |
431aa3fb | 1362 | int idx; |
5072c59f SR |
1363 | unsigned flags; |
1364 | unsigned char buffer[FTRACE_BUFF_MAX+1]; | |
1365 | unsigned buffer_idx; | |
1366 | unsigned filtered; | |
1367 | }; | |
1368 | ||
8fc0c701 SR |
1369 | static void * |
1370 | t_hash_next(struct seq_file *m, void *v, loff_t *pos) | |
1371 | { | |
1372 | struct ftrace_iterator *iter = m->private; | |
1373 | struct hlist_node *hnd = v; | |
1374 | struct hlist_head *hhd; | |
1375 | ||
1376 | WARN_ON(!(iter->flags & FTRACE_ITER_HASH)); | |
1377 | ||
1378 | (*pos)++; | |
1379 | ||
1380 | retry: | |
1381 | if (iter->hidx >= FTRACE_FUNC_HASHSIZE) | |
1382 | return NULL; | |
1383 | ||
1384 | hhd = &ftrace_func_hash[iter->hidx]; | |
1385 | ||
1386 | if (hlist_empty(hhd)) { | |
1387 | iter->hidx++; | |
1388 | hnd = NULL; | |
1389 | goto retry; | |
1390 | } | |
1391 | ||
1392 | if (!hnd) | |
1393 | hnd = hhd->first; | |
1394 | else { | |
1395 | hnd = hnd->next; | |
1396 | if (!hnd) { | |
1397 | iter->hidx++; | |
1398 | goto retry; | |
1399 | } | |
1400 | } | |
1401 | ||
1402 | return hnd; | |
1403 | } | |
1404 | ||
1405 | static void *t_hash_start(struct seq_file *m, loff_t *pos) | |
1406 | { | |
1407 | struct ftrace_iterator *iter = m->private; | |
1408 | void *p = NULL; | |
1409 | ||
1410 | iter->flags |= FTRACE_ITER_HASH; | |
1411 | ||
1412 | return t_hash_next(m, p, pos); | |
1413 | } | |
1414 | ||
1415 | static int t_hash_show(struct seq_file *m, void *v) | |
1416 | { | |
b6887d79 | 1417 | struct ftrace_func_probe *rec; |
8fc0c701 SR |
1418 | struct hlist_node *hnd = v; |
1419 | char str[KSYM_SYMBOL_LEN]; | |
1420 | ||
b6887d79 | 1421 | rec = hlist_entry(hnd, struct ftrace_func_probe, node); |
8fc0c701 | 1422 | |
809dcf29 SR |
1423 | if (rec->ops->print) |
1424 | return rec->ops->print(m, rec->ip, rec->ops, rec->data); | |
1425 | ||
8fc0c701 SR |
1426 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); |
1427 | seq_printf(m, "%s:", str); | |
1428 | ||
1429 | kallsyms_lookup((unsigned long)rec->ops->func, NULL, NULL, NULL, str); | |
1430 | seq_printf(m, "%s", str); | |
1431 | ||
1432 | if (rec->data) | |
1433 | seq_printf(m, ":%p", rec->data); | |
1434 | seq_putc(m, '\n'); | |
1435 | ||
1436 | return 0; | |
1437 | } | |
1438 | ||
e309b41d | 1439 | static void * |
5072c59f SR |
1440 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1441 | { | |
1442 | struct ftrace_iterator *iter = m->private; | |
1443 | struct dyn_ftrace *rec = NULL; | |
1444 | ||
8fc0c701 SR |
1445 | if (iter->flags & FTRACE_ITER_HASH) |
1446 | return t_hash_next(m, v, pos); | |
1447 | ||
5072c59f SR |
1448 | (*pos)++; |
1449 | ||
0c75a3ed SR |
1450 | if (iter->flags & FTRACE_ITER_PRINTALL) |
1451 | return NULL; | |
1452 | ||
5072c59f SR |
1453 | retry: |
1454 | if (iter->idx >= iter->pg->index) { | |
1455 | if (iter->pg->next) { | |
1456 | iter->pg = iter->pg->next; | |
1457 | iter->idx = 0; | |
1458 | goto retry; | |
50cdaf08 LW |
1459 | } else { |
1460 | iter->idx = -1; | |
5072c59f SR |
1461 | } |
1462 | } else { | |
1463 | rec = &iter->pg->records[iter->idx++]; | |
a9fdda33 SR |
1464 | if ((rec->flags & FTRACE_FL_FREE) || |
1465 | ||
1466 | (!(iter->flags & FTRACE_ITER_FAILURES) && | |
eb9a7bf0 AS |
1467 | (rec->flags & FTRACE_FL_FAILED)) || |
1468 | ||
1469 | ((iter->flags & FTRACE_ITER_FAILURES) && | |
a9fdda33 | 1470 | !(rec->flags & FTRACE_FL_FAILED)) || |
eb9a7bf0 | 1471 | |
0183fb1c SR |
1472 | ((iter->flags & FTRACE_ITER_FILTER) && |
1473 | !(rec->flags & FTRACE_FL_FILTER)) || | |
1474 | ||
41c52c0d SR |
1475 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
1476 | !(rec->flags & FTRACE_FL_NOTRACE))) { | |
5072c59f SR |
1477 | rec = NULL; |
1478 | goto retry; | |
1479 | } | |
1480 | } | |
1481 | ||
5072c59f SR |
1482 | return rec; |
1483 | } | |
1484 | ||
1485 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1486 | { | |
1487 | struct ftrace_iterator *iter = m->private; | |
1488 | void *p = NULL; | |
5072c59f | 1489 | |
8fc0c701 | 1490 | mutex_lock(&ftrace_lock); |
0c75a3ed SR |
1491 | /* |
1492 | * For set_ftrace_filter reading, if we have the filter | |
1493 | * off, we can short cut and just print out that all | |
1494 | * functions are enabled. | |
1495 | */ | |
1496 | if (iter->flags & FTRACE_ITER_FILTER && !ftrace_filtered) { | |
1497 | if (*pos > 0) | |
8fc0c701 | 1498 | return t_hash_start(m, pos); |
0c75a3ed SR |
1499 | iter->flags |= FTRACE_ITER_PRINTALL; |
1500 | (*pos)++; | |
1501 | return iter; | |
1502 | } | |
1503 | ||
8fc0c701 SR |
1504 | if (iter->flags & FTRACE_ITER_HASH) |
1505 | return t_hash_start(m, pos); | |
1506 | ||
50cdaf08 LW |
1507 | if (*pos > 0) { |
1508 | if (iter->idx < 0) | |
1509 | return p; | |
1510 | (*pos)--; | |
1511 | iter->idx--; | |
1512 | } | |
5821e1b7 | 1513 | |
50cdaf08 | 1514 | p = t_next(m, p, pos); |
5072c59f | 1515 | |
8fc0c701 SR |
1516 | if (!p) |
1517 | return t_hash_start(m, pos); | |
1518 | ||
5072c59f SR |
1519 | return p; |
1520 | } | |
1521 | ||
1522 | static void t_stop(struct seq_file *m, void *p) | |
1523 | { | |
8fc0c701 | 1524 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
1525 | } |
1526 | ||
1527 | static int t_show(struct seq_file *m, void *v) | |
1528 | { | |
0c75a3ed | 1529 | struct ftrace_iterator *iter = m->private; |
5072c59f SR |
1530 | struct dyn_ftrace *rec = v; |
1531 | char str[KSYM_SYMBOL_LEN]; | |
1532 | ||
8fc0c701 SR |
1533 | if (iter->flags & FTRACE_ITER_HASH) |
1534 | return t_hash_show(m, v); | |
1535 | ||
0c75a3ed SR |
1536 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
1537 | seq_printf(m, "#### all functions enabled ####\n"); | |
1538 | return 0; | |
1539 | } | |
1540 | ||
5072c59f SR |
1541 | if (!rec) |
1542 | return 0; | |
1543 | ||
1544 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
1545 | ||
50cdaf08 | 1546 | seq_printf(m, "%s\n", str); |
5072c59f SR |
1547 | |
1548 | return 0; | |
1549 | } | |
1550 | ||
1551 | static struct seq_operations show_ftrace_seq_ops = { | |
1552 | .start = t_start, | |
1553 | .next = t_next, | |
1554 | .stop = t_stop, | |
1555 | .show = t_show, | |
1556 | }; | |
1557 | ||
e309b41d | 1558 | static int |
5072c59f SR |
1559 | ftrace_avail_open(struct inode *inode, struct file *file) |
1560 | { | |
1561 | struct ftrace_iterator *iter; | |
1562 | int ret; | |
1563 | ||
4eebcc81 SR |
1564 | if (unlikely(ftrace_disabled)) |
1565 | return -ENODEV; | |
1566 | ||
5072c59f SR |
1567 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
1568 | if (!iter) | |
1569 | return -ENOMEM; | |
1570 | ||
1571 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
1572 | |
1573 | ret = seq_open(file, &show_ftrace_seq_ops); | |
1574 | if (!ret) { | |
1575 | struct seq_file *m = file->private_data; | |
4bf39a94 | 1576 | |
5072c59f | 1577 | m->private = iter; |
4bf39a94 | 1578 | } else { |
5072c59f | 1579 | kfree(iter); |
4bf39a94 | 1580 | } |
5072c59f SR |
1581 | |
1582 | return ret; | |
1583 | } | |
1584 | ||
1585 | int ftrace_avail_release(struct inode *inode, struct file *file) | |
1586 | { | |
1587 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1588 | struct ftrace_iterator *iter = m->private; | |
1589 | ||
1590 | seq_release(inode, file); | |
1591 | kfree(iter); | |
4bf39a94 | 1592 | |
5072c59f SR |
1593 | return 0; |
1594 | } | |
1595 | ||
eb9a7bf0 AS |
1596 | static int |
1597 | ftrace_failures_open(struct inode *inode, struct file *file) | |
1598 | { | |
1599 | int ret; | |
1600 | struct seq_file *m; | |
1601 | struct ftrace_iterator *iter; | |
1602 | ||
1603 | ret = ftrace_avail_open(inode, file); | |
1604 | if (!ret) { | |
1605 | m = (struct seq_file *)file->private_data; | |
1606 | iter = (struct ftrace_iterator *)m->private; | |
1607 | iter->flags = FTRACE_ITER_FAILURES; | |
1608 | } | |
1609 | ||
1610 | return ret; | |
1611 | } | |
1612 | ||
1613 | ||
41c52c0d | 1614 | static void ftrace_filter_reset(int enable) |
5072c59f SR |
1615 | { |
1616 | struct ftrace_page *pg; | |
1617 | struct dyn_ftrace *rec; | |
41c52c0d | 1618 | unsigned long type = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
5072c59f | 1619 | |
52baf119 | 1620 | mutex_lock(&ftrace_lock); |
41c52c0d SR |
1621 | if (enable) |
1622 | ftrace_filtered = 0; | |
265c831c SR |
1623 | do_for_each_ftrace_rec(pg, rec) { |
1624 | if (rec->flags & FTRACE_FL_FAILED) | |
1625 | continue; | |
1626 | rec->flags &= ~type; | |
1627 | } while_for_each_ftrace_rec(); | |
52baf119 | 1628 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
1629 | } |
1630 | ||
e309b41d | 1631 | static int |
41c52c0d | 1632 | ftrace_regex_open(struct inode *inode, struct file *file, int enable) |
5072c59f SR |
1633 | { |
1634 | struct ftrace_iterator *iter; | |
1635 | int ret = 0; | |
1636 | ||
4eebcc81 SR |
1637 | if (unlikely(ftrace_disabled)) |
1638 | return -ENODEV; | |
1639 | ||
5072c59f SR |
1640 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
1641 | if (!iter) | |
1642 | return -ENOMEM; | |
1643 | ||
41c52c0d | 1644 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
1645 | if ((file->f_mode & FMODE_WRITE) && |
1646 | !(file->f_flags & O_APPEND)) | |
41c52c0d | 1647 | ftrace_filter_reset(enable); |
5072c59f SR |
1648 | |
1649 | if (file->f_mode & FMODE_READ) { | |
1650 | iter->pg = ftrace_pages_start; | |
41c52c0d SR |
1651 | iter->flags = enable ? FTRACE_ITER_FILTER : |
1652 | FTRACE_ITER_NOTRACE; | |
5072c59f SR |
1653 | |
1654 | ret = seq_open(file, &show_ftrace_seq_ops); | |
1655 | if (!ret) { | |
1656 | struct seq_file *m = file->private_data; | |
1657 | m->private = iter; | |
1658 | } else | |
1659 | kfree(iter); | |
1660 | } else | |
1661 | file->private_data = iter; | |
41c52c0d | 1662 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
1663 | |
1664 | return ret; | |
1665 | } | |
1666 | ||
41c52c0d SR |
1667 | static int |
1668 | ftrace_filter_open(struct inode *inode, struct file *file) | |
1669 | { | |
1670 | return ftrace_regex_open(inode, file, 1); | |
1671 | } | |
1672 | ||
1673 | static int | |
1674 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
1675 | { | |
1676 | return ftrace_regex_open(inode, file, 0); | |
1677 | } | |
1678 | ||
e309b41d | 1679 | static loff_t |
41c52c0d | 1680 | ftrace_regex_lseek(struct file *file, loff_t offset, int origin) |
5072c59f SR |
1681 | { |
1682 | loff_t ret; | |
1683 | ||
1684 | if (file->f_mode & FMODE_READ) | |
1685 | ret = seq_lseek(file, offset, origin); | |
1686 | else | |
1687 | file->f_pos = ret = 1; | |
1688 | ||
1689 | return ret; | |
1690 | } | |
1691 | ||
1692 | enum { | |
1693 | MATCH_FULL, | |
1694 | MATCH_FRONT_ONLY, | |
1695 | MATCH_MIDDLE_ONLY, | |
1696 | MATCH_END_ONLY, | |
1697 | }; | |
1698 | ||
9f4801e3 SR |
1699 | /* |
1700 | * (static function - no need for kernel doc) | |
1701 | * | |
1702 | * Pass in a buffer containing a glob and this function will | |
1703 | * set search to point to the search part of the buffer and | |
1704 | * return the type of search it is (see enum above). | |
1705 | * This does modify buff. | |
1706 | * | |
1707 | * Returns enum type. | |
1708 | * search returns the pointer to use for comparison. | |
1709 | * not returns 1 if buff started with a '!' | |
1710 | * 0 otherwise. | |
1711 | */ | |
1712 | static int | |
64e7c440 | 1713 | ftrace_setup_glob(char *buff, int len, char **search, int *not) |
5072c59f | 1714 | { |
5072c59f | 1715 | int type = MATCH_FULL; |
9f4801e3 | 1716 | int i; |
ea3a6d6d SR |
1717 | |
1718 | if (buff[0] == '!') { | |
9f4801e3 | 1719 | *not = 1; |
ea3a6d6d SR |
1720 | buff++; |
1721 | len--; | |
9f4801e3 SR |
1722 | } else |
1723 | *not = 0; | |
1724 | ||
1725 | *search = buff; | |
5072c59f SR |
1726 | |
1727 | for (i = 0; i < len; i++) { | |
1728 | if (buff[i] == '*') { | |
1729 | if (!i) { | |
9f4801e3 | 1730 | *search = buff + 1; |
5072c59f | 1731 | type = MATCH_END_ONLY; |
5072c59f | 1732 | } else { |
9f4801e3 | 1733 | if (type == MATCH_END_ONLY) |
5072c59f | 1734 | type = MATCH_MIDDLE_ONLY; |
9f4801e3 | 1735 | else |
5072c59f | 1736 | type = MATCH_FRONT_ONLY; |
5072c59f SR |
1737 | buff[i] = 0; |
1738 | break; | |
1739 | } | |
1740 | } | |
1741 | } | |
1742 | ||
9f4801e3 SR |
1743 | return type; |
1744 | } | |
1745 | ||
64e7c440 | 1746 | static int ftrace_match(char *str, char *regex, int len, int type) |
9f4801e3 | 1747 | { |
9f4801e3 SR |
1748 | int matched = 0; |
1749 | char *ptr; | |
1750 | ||
9f4801e3 SR |
1751 | switch (type) { |
1752 | case MATCH_FULL: | |
1753 | if (strcmp(str, regex) == 0) | |
1754 | matched = 1; | |
1755 | break; | |
1756 | case MATCH_FRONT_ONLY: | |
1757 | if (strncmp(str, regex, len) == 0) | |
1758 | matched = 1; | |
1759 | break; | |
1760 | case MATCH_MIDDLE_ONLY: | |
1761 | if (strstr(str, regex)) | |
1762 | matched = 1; | |
1763 | break; | |
1764 | case MATCH_END_ONLY: | |
1765 | ptr = strstr(str, regex); | |
1766 | if (ptr && (ptr[len] == 0)) | |
1767 | matched = 1; | |
1768 | break; | |
1769 | } | |
1770 | ||
1771 | return matched; | |
1772 | } | |
1773 | ||
64e7c440 SR |
1774 | static int |
1775 | ftrace_match_record(struct dyn_ftrace *rec, char *regex, int len, int type) | |
1776 | { | |
1777 | char str[KSYM_SYMBOL_LEN]; | |
1778 | ||
1779 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
1780 | return ftrace_match(str, regex, len, type); | |
1781 | } | |
1782 | ||
9f4801e3 SR |
1783 | static void ftrace_match_records(char *buff, int len, int enable) |
1784 | { | |
6a24a244 | 1785 | unsigned int search_len; |
9f4801e3 SR |
1786 | struct ftrace_page *pg; |
1787 | struct dyn_ftrace *rec; | |
6a24a244 SR |
1788 | unsigned long flag; |
1789 | char *search; | |
9f4801e3 | 1790 | int type; |
9f4801e3 SR |
1791 | int not; |
1792 | ||
6a24a244 | 1793 | flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
9f4801e3 SR |
1794 | type = ftrace_setup_glob(buff, len, &search, ¬); |
1795 | ||
1796 | search_len = strlen(search); | |
1797 | ||
52baf119 | 1798 | mutex_lock(&ftrace_lock); |
265c831c | 1799 | do_for_each_ftrace_rec(pg, rec) { |
265c831c SR |
1800 | |
1801 | if (rec->flags & FTRACE_FL_FAILED) | |
1802 | continue; | |
9f4801e3 SR |
1803 | |
1804 | if (ftrace_match_record(rec, search, search_len, type)) { | |
265c831c SR |
1805 | if (not) |
1806 | rec->flags &= ~flag; | |
1807 | else | |
1808 | rec->flags |= flag; | |
1809 | } | |
e68746a2 SR |
1810 | /* |
1811 | * Only enable filtering if we have a function that | |
1812 | * is filtered on. | |
1813 | */ | |
1814 | if (enable && (rec->flags & FTRACE_FL_FILTER)) | |
1815 | ftrace_filtered = 1; | |
265c831c | 1816 | } while_for_each_ftrace_rec(); |
52baf119 | 1817 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
1818 | } |
1819 | ||
64e7c440 SR |
1820 | static int |
1821 | ftrace_match_module_record(struct dyn_ftrace *rec, char *mod, | |
1822 | char *regex, int len, int type) | |
1823 | { | |
1824 | char str[KSYM_SYMBOL_LEN]; | |
1825 | char *modname; | |
1826 | ||
1827 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); | |
1828 | ||
1829 | if (!modname || strcmp(modname, mod)) | |
1830 | return 0; | |
1831 | ||
1832 | /* blank search means to match all funcs in the mod */ | |
1833 | if (len) | |
1834 | return ftrace_match(str, regex, len, type); | |
1835 | else | |
1836 | return 1; | |
1837 | } | |
1838 | ||
1839 | static void ftrace_match_module_records(char *buff, char *mod, int enable) | |
1840 | { | |
6a24a244 | 1841 | unsigned search_len = 0; |
64e7c440 SR |
1842 | struct ftrace_page *pg; |
1843 | struct dyn_ftrace *rec; | |
1844 | int type = MATCH_FULL; | |
6a24a244 SR |
1845 | char *search = buff; |
1846 | unsigned long flag; | |
64e7c440 SR |
1847 | int not = 0; |
1848 | ||
6a24a244 SR |
1849 | flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
1850 | ||
64e7c440 SR |
1851 | /* blank or '*' mean the same */ |
1852 | if (strcmp(buff, "*") == 0) | |
1853 | buff[0] = 0; | |
1854 | ||
1855 | /* handle the case of 'dont filter this module' */ | |
1856 | if (strcmp(buff, "!") == 0 || strcmp(buff, "!*") == 0) { | |
1857 | buff[0] = 0; | |
1858 | not = 1; | |
1859 | } | |
1860 | ||
1861 | if (strlen(buff)) { | |
1862 | type = ftrace_setup_glob(buff, strlen(buff), &search, ¬); | |
1863 | search_len = strlen(search); | |
1864 | } | |
1865 | ||
52baf119 | 1866 | mutex_lock(&ftrace_lock); |
64e7c440 SR |
1867 | do_for_each_ftrace_rec(pg, rec) { |
1868 | ||
1869 | if (rec->flags & FTRACE_FL_FAILED) | |
1870 | continue; | |
1871 | ||
1872 | if (ftrace_match_module_record(rec, mod, | |
1873 | search, search_len, type)) { | |
1874 | if (not) | |
1875 | rec->flags &= ~flag; | |
1876 | else | |
1877 | rec->flags |= flag; | |
1878 | } | |
e68746a2 SR |
1879 | if (enable && (rec->flags & FTRACE_FL_FILTER)) |
1880 | ftrace_filtered = 1; | |
64e7c440 SR |
1881 | |
1882 | } while_for_each_ftrace_rec(); | |
52baf119 | 1883 | mutex_unlock(&ftrace_lock); |
64e7c440 SR |
1884 | } |
1885 | ||
f6180773 SR |
1886 | /* |
1887 | * We register the module command as a template to show others how | |
1888 | * to register the a command as well. | |
1889 | */ | |
1890 | ||
1891 | static int | |
1892 | ftrace_mod_callback(char *func, char *cmd, char *param, int enable) | |
1893 | { | |
1894 | char *mod; | |
1895 | ||
1896 | /* | |
1897 | * cmd == 'mod' because we only registered this func | |
1898 | * for the 'mod' ftrace_func_command. | |
1899 | * But if you register one func with multiple commands, | |
1900 | * you can tell which command was used by the cmd | |
1901 | * parameter. | |
1902 | */ | |
1903 | ||
1904 | /* we must have a module name */ | |
1905 | if (!param) | |
1906 | return -EINVAL; | |
1907 | ||
1908 | mod = strsep(¶m, ":"); | |
1909 | if (!strlen(mod)) | |
1910 | return -EINVAL; | |
1911 | ||
1912 | ftrace_match_module_records(func, mod, enable); | |
1913 | return 0; | |
1914 | } | |
1915 | ||
1916 | static struct ftrace_func_command ftrace_mod_cmd = { | |
1917 | .name = "mod", | |
1918 | .func = ftrace_mod_callback, | |
1919 | }; | |
1920 | ||
1921 | static int __init ftrace_mod_cmd_init(void) | |
1922 | { | |
1923 | return register_ftrace_command(&ftrace_mod_cmd); | |
1924 | } | |
1925 | device_initcall(ftrace_mod_cmd_init); | |
1926 | ||
59df055f | 1927 | static void |
b6887d79 | 1928 | function_trace_probe_call(unsigned long ip, unsigned long parent_ip) |
59df055f | 1929 | { |
b6887d79 | 1930 | struct ftrace_func_probe *entry; |
59df055f SR |
1931 | struct hlist_head *hhd; |
1932 | struct hlist_node *n; | |
1933 | unsigned long key; | |
1934 | int resched; | |
1935 | ||
1936 | key = hash_long(ip, FTRACE_HASH_BITS); | |
1937 | ||
1938 | hhd = &ftrace_func_hash[key]; | |
1939 | ||
1940 | if (hlist_empty(hhd)) | |
1941 | return; | |
1942 | ||
1943 | /* | |
1944 | * Disable preemption for these calls to prevent a RCU grace | |
1945 | * period. This syncs the hash iteration and freeing of items | |
1946 | * on the hash. rcu_read_lock is too dangerous here. | |
1947 | */ | |
1948 | resched = ftrace_preempt_disable(); | |
1949 | hlist_for_each_entry_rcu(entry, n, hhd, node) { | |
1950 | if (entry->ip == ip) | |
1951 | entry->ops->func(ip, parent_ip, &entry->data); | |
1952 | } | |
1953 | ftrace_preempt_enable(resched); | |
1954 | } | |
1955 | ||
b6887d79 | 1956 | static struct ftrace_ops trace_probe_ops __read_mostly = |
59df055f | 1957 | { |
fb9fb015 | 1958 | .func = function_trace_probe_call, |
59df055f SR |
1959 | }; |
1960 | ||
b6887d79 | 1961 | static int ftrace_probe_registered; |
59df055f | 1962 | |
b6887d79 | 1963 | static void __enable_ftrace_function_probe(void) |
59df055f SR |
1964 | { |
1965 | int i; | |
1966 | ||
b6887d79 | 1967 | if (ftrace_probe_registered) |
59df055f SR |
1968 | return; |
1969 | ||
1970 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
1971 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
1972 | if (hhd->first) | |
1973 | break; | |
1974 | } | |
1975 | /* Nothing registered? */ | |
1976 | if (i == FTRACE_FUNC_HASHSIZE) | |
1977 | return; | |
1978 | ||
b6887d79 | 1979 | __register_ftrace_function(&trace_probe_ops); |
59df055f | 1980 | ftrace_startup(0); |
b6887d79 | 1981 | ftrace_probe_registered = 1; |
59df055f SR |
1982 | } |
1983 | ||
b6887d79 | 1984 | static void __disable_ftrace_function_probe(void) |
59df055f SR |
1985 | { |
1986 | int i; | |
1987 | ||
b6887d79 | 1988 | if (!ftrace_probe_registered) |
59df055f SR |
1989 | return; |
1990 | ||
1991 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
1992 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
1993 | if (hhd->first) | |
1994 | return; | |
1995 | } | |
1996 | ||
1997 | /* no more funcs left */ | |
b6887d79 | 1998 | __unregister_ftrace_function(&trace_probe_ops); |
59df055f | 1999 | ftrace_shutdown(0); |
b6887d79 | 2000 | ftrace_probe_registered = 0; |
59df055f SR |
2001 | } |
2002 | ||
2003 | ||
2004 | static void ftrace_free_entry_rcu(struct rcu_head *rhp) | |
2005 | { | |
b6887d79 SR |
2006 | struct ftrace_func_probe *entry = |
2007 | container_of(rhp, struct ftrace_func_probe, rcu); | |
59df055f SR |
2008 | |
2009 | if (entry->ops->free) | |
2010 | entry->ops->free(&entry->data); | |
2011 | kfree(entry); | |
2012 | } | |
2013 | ||
2014 | ||
2015 | int | |
b6887d79 | 2016 | register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
2017 | void *data) |
2018 | { | |
b6887d79 | 2019 | struct ftrace_func_probe *entry; |
59df055f SR |
2020 | struct ftrace_page *pg; |
2021 | struct dyn_ftrace *rec; | |
59df055f | 2022 | int type, len, not; |
6a24a244 | 2023 | unsigned long key; |
59df055f SR |
2024 | int count = 0; |
2025 | char *search; | |
2026 | ||
2027 | type = ftrace_setup_glob(glob, strlen(glob), &search, ¬); | |
2028 | len = strlen(search); | |
2029 | ||
b6887d79 | 2030 | /* we do not support '!' for function probes */ |
59df055f SR |
2031 | if (WARN_ON(not)) |
2032 | return -EINVAL; | |
2033 | ||
2034 | mutex_lock(&ftrace_lock); | |
2035 | do_for_each_ftrace_rec(pg, rec) { | |
2036 | ||
2037 | if (rec->flags & FTRACE_FL_FAILED) | |
2038 | continue; | |
2039 | ||
2040 | if (!ftrace_match_record(rec, search, len, type)) | |
2041 | continue; | |
2042 | ||
2043 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
2044 | if (!entry) { | |
b6887d79 | 2045 | /* If we did not process any, then return error */ |
59df055f SR |
2046 | if (!count) |
2047 | count = -ENOMEM; | |
2048 | goto out_unlock; | |
2049 | } | |
2050 | ||
2051 | count++; | |
2052 | ||
2053 | entry->data = data; | |
2054 | ||
2055 | /* | |
2056 | * The caller might want to do something special | |
2057 | * for each function we find. We call the callback | |
2058 | * to give the caller an opportunity to do so. | |
2059 | */ | |
2060 | if (ops->callback) { | |
2061 | if (ops->callback(rec->ip, &entry->data) < 0) { | |
2062 | /* caller does not like this func */ | |
2063 | kfree(entry); | |
2064 | continue; | |
2065 | } | |
2066 | } | |
2067 | ||
2068 | entry->ops = ops; | |
2069 | entry->ip = rec->ip; | |
2070 | ||
2071 | key = hash_long(entry->ip, FTRACE_HASH_BITS); | |
2072 | hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]); | |
2073 | ||
2074 | } while_for_each_ftrace_rec(); | |
b6887d79 | 2075 | __enable_ftrace_function_probe(); |
59df055f SR |
2076 | |
2077 | out_unlock: | |
2078 | mutex_unlock(&ftrace_lock); | |
2079 | ||
2080 | return count; | |
2081 | } | |
2082 | ||
2083 | enum { | |
b6887d79 SR |
2084 | PROBE_TEST_FUNC = 1, |
2085 | PROBE_TEST_DATA = 2 | |
59df055f SR |
2086 | }; |
2087 | ||
2088 | static void | |
b6887d79 | 2089 | __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
2090 | void *data, int flags) |
2091 | { | |
b6887d79 | 2092 | struct ftrace_func_probe *entry; |
59df055f SR |
2093 | struct hlist_node *n, *tmp; |
2094 | char str[KSYM_SYMBOL_LEN]; | |
2095 | int type = MATCH_FULL; | |
2096 | int i, len = 0; | |
2097 | char *search; | |
2098 | ||
2099 | if (glob && (strcmp(glob, "*") || !strlen(glob))) | |
2100 | glob = NULL; | |
2101 | else { | |
2102 | int not; | |
2103 | ||
2104 | type = ftrace_setup_glob(glob, strlen(glob), &search, ¬); | |
2105 | len = strlen(search); | |
2106 | ||
b6887d79 | 2107 | /* we do not support '!' for function probes */ |
59df055f SR |
2108 | if (WARN_ON(not)) |
2109 | return; | |
2110 | } | |
2111 | ||
2112 | mutex_lock(&ftrace_lock); | |
2113 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
2114 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
2115 | ||
2116 | hlist_for_each_entry_safe(entry, n, tmp, hhd, node) { | |
2117 | ||
2118 | /* break up if statements for readability */ | |
b6887d79 | 2119 | if ((flags & PROBE_TEST_FUNC) && entry->ops != ops) |
59df055f SR |
2120 | continue; |
2121 | ||
b6887d79 | 2122 | if ((flags & PROBE_TEST_DATA) && entry->data != data) |
59df055f SR |
2123 | continue; |
2124 | ||
2125 | /* do this last, since it is the most expensive */ | |
2126 | if (glob) { | |
2127 | kallsyms_lookup(entry->ip, NULL, NULL, | |
2128 | NULL, str); | |
2129 | if (!ftrace_match(str, glob, len, type)) | |
2130 | continue; | |
2131 | } | |
2132 | ||
2133 | hlist_del(&entry->node); | |
2134 | call_rcu(&entry->rcu, ftrace_free_entry_rcu); | |
2135 | } | |
2136 | } | |
b6887d79 | 2137 | __disable_ftrace_function_probe(); |
59df055f SR |
2138 | mutex_unlock(&ftrace_lock); |
2139 | } | |
2140 | ||
2141 | void | |
b6887d79 | 2142 | unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
2143 | void *data) |
2144 | { | |
b6887d79 SR |
2145 | __unregister_ftrace_function_probe(glob, ops, data, |
2146 | PROBE_TEST_FUNC | PROBE_TEST_DATA); | |
59df055f SR |
2147 | } |
2148 | ||
2149 | void | |
b6887d79 | 2150 | unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops) |
59df055f | 2151 | { |
b6887d79 | 2152 | __unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC); |
59df055f SR |
2153 | } |
2154 | ||
b6887d79 | 2155 | void unregister_ftrace_function_probe_all(char *glob) |
59df055f | 2156 | { |
b6887d79 | 2157 | __unregister_ftrace_function_probe(glob, NULL, NULL, 0); |
59df055f SR |
2158 | } |
2159 | ||
f6180773 SR |
2160 | static LIST_HEAD(ftrace_commands); |
2161 | static DEFINE_MUTEX(ftrace_cmd_mutex); | |
2162 | ||
2163 | int register_ftrace_command(struct ftrace_func_command *cmd) | |
2164 | { | |
2165 | struct ftrace_func_command *p; | |
2166 | int ret = 0; | |
2167 | ||
2168 | mutex_lock(&ftrace_cmd_mutex); | |
2169 | list_for_each_entry(p, &ftrace_commands, list) { | |
2170 | if (strcmp(cmd->name, p->name) == 0) { | |
2171 | ret = -EBUSY; | |
2172 | goto out_unlock; | |
2173 | } | |
2174 | } | |
2175 | list_add(&cmd->list, &ftrace_commands); | |
2176 | out_unlock: | |
2177 | mutex_unlock(&ftrace_cmd_mutex); | |
2178 | ||
2179 | return ret; | |
2180 | } | |
2181 | ||
2182 | int unregister_ftrace_command(struct ftrace_func_command *cmd) | |
2183 | { | |
2184 | struct ftrace_func_command *p, *n; | |
2185 | int ret = -ENODEV; | |
2186 | ||
2187 | mutex_lock(&ftrace_cmd_mutex); | |
2188 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { | |
2189 | if (strcmp(cmd->name, p->name) == 0) { | |
2190 | ret = 0; | |
2191 | list_del_init(&p->list); | |
2192 | goto out_unlock; | |
2193 | } | |
2194 | } | |
2195 | out_unlock: | |
2196 | mutex_unlock(&ftrace_cmd_mutex); | |
2197 | ||
2198 | return ret; | |
2199 | } | |
2200 | ||
64e7c440 SR |
2201 | static int ftrace_process_regex(char *buff, int len, int enable) |
2202 | { | |
f6180773 | 2203 | char *func, *command, *next = buff; |
6a24a244 | 2204 | struct ftrace_func_command *p; |
f6180773 | 2205 | int ret = -EINVAL; |
64e7c440 SR |
2206 | |
2207 | func = strsep(&next, ":"); | |
2208 | ||
2209 | if (!next) { | |
2210 | ftrace_match_records(func, len, enable); | |
2211 | return 0; | |
2212 | } | |
2213 | ||
f6180773 | 2214 | /* command found */ |
64e7c440 SR |
2215 | |
2216 | command = strsep(&next, ":"); | |
2217 | ||
f6180773 SR |
2218 | mutex_lock(&ftrace_cmd_mutex); |
2219 | list_for_each_entry(p, &ftrace_commands, list) { | |
2220 | if (strcmp(p->name, command) == 0) { | |
2221 | ret = p->func(func, command, next, enable); | |
2222 | goto out_unlock; | |
2223 | } | |
64e7c440 | 2224 | } |
f6180773 SR |
2225 | out_unlock: |
2226 | mutex_unlock(&ftrace_cmd_mutex); | |
64e7c440 | 2227 | |
f6180773 | 2228 | return ret; |
64e7c440 SR |
2229 | } |
2230 | ||
e309b41d | 2231 | static ssize_t |
41c52c0d SR |
2232 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
2233 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
2234 | { |
2235 | struct ftrace_iterator *iter; | |
2236 | char ch; | |
2237 | size_t read = 0; | |
2238 | ssize_t ret; | |
2239 | ||
2240 | if (!cnt || cnt < 0) | |
2241 | return 0; | |
2242 | ||
41c52c0d | 2243 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
2244 | |
2245 | if (file->f_mode & FMODE_READ) { | |
2246 | struct seq_file *m = file->private_data; | |
2247 | iter = m->private; | |
2248 | } else | |
2249 | iter = file->private_data; | |
2250 | ||
2251 | if (!*ppos) { | |
2252 | iter->flags &= ~FTRACE_ITER_CONT; | |
2253 | iter->buffer_idx = 0; | |
2254 | } | |
2255 | ||
2256 | ret = get_user(ch, ubuf++); | |
2257 | if (ret) | |
2258 | goto out; | |
2259 | read++; | |
2260 | cnt--; | |
2261 | ||
2262 | if (!(iter->flags & ~FTRACE_ITER_CONT)) { | |
2263 | /* skip white space */ | |
2264 | while (cnt && isspace(ch)) { | |
2265 | ret = get_user(ch, ubuf++); | |
2266 | if (ret) | |
2267 | goto out; | |
2268 | read++; | |
2269 | cnt--; | |
2270 | } | |
2271 | ||
5072c59f SR |
2272 | if (isspace(ch)) { |
2273 | file->f_pos += read; | |
2274 | ret = read; | |
2275 | goto out; | |
2276 | } | |
2277 | ||
2278 | iter->buffer_idx = 0; | |
2279 | } | |
2280 | ||
2281 | while (cnt && !isspace(ch)) { | |
2282 | if (iter->buffer_idx < FTRACE_BUFF_MAX) | |
2283 | iter->buffer[iter->buffer_idx++] = ch; | |
2284 | else { | |
2285 | ret = -EINVAL; | |
2286 | goto out; | |
2287 | } | |
2288 | ret = get_user(ch, ubuf++); | |
2289 | if (ret) | |
2290 | goto out; | |
2291 | read++; | |
2292 | cnt--; | |
2293 | } | |
2294 | ||
2295 | if (isspace(ch)) { | |
2296 | iter->filtered++; | |
2297 | iter->buffer[iter->buffer_idx] = 0; | |
64e7c440 SR |
2298 | ret = ftrace_process_regex(iter->buffer, |
2299 | iter->buffer_idx, enable); | |
2300 | if (ret) | |
2301 | goto out; | |
5072c59f SR |
2302 | iter->buffer_idx = 0; |
2303 | } else | |
2304 | iter->flags |= FTRACE_ITER_CONT; | |
2305 | ||
2306 | ||
2307 | file->f_pos += read; | |
2308 | ||
2309 | ret = read; | |
2310 | out: | |
41c52c0d | 2311 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
2312 | |
2313 | return ret; | |
2314 | } | |
2315 | ||
41c52c0d SR |
2316 | static ssize_t |
2317 | ftrace_filter_write(struct file *file, const char __user *ubuf, | |
2318 | size_t cnt, loff_t *ppos) | |
2319 | { | |
2320 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
2321 | } | |
2322 | ||
2323 | static ssize_t | |
2324 | ftrace_notrace_write(struct file *file, const char __user *ubuf, | |
2325 | size_t cnt, loff_t *ppos) | |
2326 | { | |
2327 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
2328 | } | |
2329 | ||
2330 | static void | |
2331 | ftrace_set_regex(unsigned char *buf, int len, int reset, int enable) | |
2332 | { | |
2333 | if (unlikely(ftrace_disabled)) | |
2334 | return; | |
2335 | ||
2336 | mutex_lock(&ftrace_regex_lock); | |
2337 | if (reset) | |
2338 | ftrace_filter_reset(enable); | |
2339 | if (buf) | |
7f24b31b | 2340 | ftrace_match_records(buf, len, enable); |
41c52c0d SR |
2341 | mutex_unlock(&ftrace_regex_lock); |
2342 | } | |
2343 | ||
77a2b37d SR |
2344 | /** |
2345 | * ftrace_set_filter - set a function to filter on in ftrace | |
2346 | * @buf - the string that holds the function filter text. | |
2347 | * @len - the length of the string. | |
2348 | * @reset - non zero to reset all filters before applying this filter. | |
2349 | * | |
2350 | * Filters denote which functions should be enabled when tracing is enabled. | |
2351 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
2352 | */ | |
e309b41d | 2353 | void ftrace_set_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 2354 | { |
41c52c0d SR |
2355 | ftrace_set_regex(buf, len, reset, 1); |
2356 | } | |
4eebcc81 | 2357 | |
41c52c0d SR |
2358 | /** |
2359 | * ftrace_set_notrace - set a function to not trace in ftrace | |
2360 | * @buf - the string that holds the function notrace text. | |
2361 | * @len - the length of the string. | |
2362 | * @reset - non zero to reset all filters before applying this filter. | |
2363 | * | |
2364 | * Notrace Filters denote which functions should not be enabled when tracing | |
2365 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
2366 | * for tracing. | |
2367 | */ | |
2368 | void ftrace_set_notrace(unsigned char *buf, int len, int reset) | |
2369 | { | |
2370 | ftrace_set_regex(buf, len, reset, 0); | |
77a2b37d SR |
2371 | } |
2372 | ||
2af15d6a SR |
2373 | /* |
2374 | * command line interface to allow users to set filters on boot up. | |
2375 | */ | |
2376 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE | |
2377 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; | |
2378 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; | |
2379 | ||
2380 | static int __init set_ftrace_notrace(char *str) | |
2381 | { | |
2382 | strncpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); | |
2383 | return 1; | |
2384 | } | |
2385 | __setup("ftrace_notrace=", set_ftrace_notrace); | |
2386 | ||
2387 | static int __init set_ftrace_filter(char *str) | |
2388 | { | |
2389 | strncpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); | |
2390 | return 1; | |
2391 | } | |
2392 | __setup("ftrace_filter=", set_ftrace_filter); | |
2393 | ||
2394 | static void __init set_ftrace_early_filter(char *buf, int enable) | |
2395 | { | |
2396 | char *func; | |
2397 | ||
2398 | while (buf) { | |
2399 | func = strsep(&buf, ","); | |
2400 | ftrace_set_regex(func, strlen(func), 0, enable); | |
2401 | } | |
2402 | } | |
2403 | ||
2404 | static void __init set_ftrace_early_filters(void) | |
2405 | { | |
2406 | if (ftrace_filter_buf[0]) | |
2407 | set_ftrace_early_filter(ftrace_filter_buf, 1); | |
2408 | if (ftrace_notrace_buf[0]) | |
2409 | set_ftrace_early_filter(ftrace_notrace_buf, 0); | |
2410 | } | |
2411 | ||
e309b41d | 2412 | static int |
41c52c0d | 2413 | ftrace_regex_release(struct inode *inode, struct file *file, int enable) |
5072c59f SR |
2414 | { |
2415 | struct seq_file *m = (struct seq_file *)file->private_data; | |
2416 | struct ftrace_iterator *iter; | |
2417 | ||
41c52c0d | 2418 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
2419 | if (file->f_mode & FMODE_READ) { |
2420 | iter = m->private; | |
2421 | ||
2422 | seq_release(inode, file); | |
2423 | } else | |
2424 | iter = file->private_data; | |
2425 | ||
2426 | if (iter->buffer_idx) { | |
2427 | iter->filtered++; | |
2428 | iter->buffer[iter->buffer_idx] = 0; | |
7f24b31b | 2429 | ftrace_match_records(iter->buffer, iter->buffer_idx, enable); |
5072c59f SR |
2430 | } |
2431 | ||
e6ea44e9 | 2432 | mutex_lock(&ftrace_lock); |
ee02a2e5 | 2433 | if (ftrace_start_up && ftrace_enabled) |
5072c59f | 2434 | ftrace_run_update_code(FTRACE_ENABLE_CALLS); |
e6ea44e9 | 2435 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
2436 | |
2437 | kfree(iter); | |
41c52c0d | 2438 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
2439 | return 0; |
2440 | } | |
2441 | ||
41c52c0d SR |
2442 | static int |
2443 | ftrace_filter_release(struct inode *inode, struct file *file) | |
2444 | { | |
2445 | return ftrace_regex_release(inode, file, 1); | |
2446 | } | |
2447 | ||
2448 | static int | |
2449 | ftrace_notrace_release(struct inode *inode, struct file *file) | |
2450 | { | |
2451 | return ftrace_regex_release(inode, file, 0); | |
2452 | } | |
2453 | ||
5e2336a0 | 2454 | static const struct file_operations ftrace_avail_fops = { |
5072c59f SR |
2455 | .open = ftrace_avail_open, |
2456 | .read = seq_read, | |
2457 | .llseek = seq_lseek, | |
2458 | .release = ftrace_avail_release, | |
2459 | }; | |
2460 | ||
5e2336a0 | 2461 | static const struct file_operations ftrace_failures_fops = { |
eb9a7bf0 AS |
2462 | .open = ftrace_failures_open, |
2463 | .read = seq_read, | |
2464 | .llseek = seq_lseek, | |
2465 | .release = ftrace_avail_release, | |
2466 | }; | |
2467 | ||
5e2336a0 | 2468 | static const struct file_operations ftrace_filter_fops = { |
5072c59f | 2469 | .open = ftrace_filter_open, |
850a80cf | 2470 | .read = seq_read, |
5072c59f | 2471 | .write = ftrace_filter_write, |
41c52c0d | 2472 | .llseek = ftrace_regex_lseek, |
5072c59f SR |
2473 | .release = ftrace_filter_release, |
2474 | }; | |
2475 | ||
5e2336a0 | 2476 | static const struct file_operations ftrace_notrace_fops = { |
41c52c0d | 2477 | .open = ftrace_notrace_open, |
850a80cf | 2478 | .read = seq_read, |
41c52c0d SR |
2479 | .write = ftrace_notrace_write, |
2480 | .llseek = ftrace_regex_lseek, | |
2481 | .release = ftrace_notrace_release, | |
2482 | }; | |
2483 | ||
ea4e2bc4 SR |
2484 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
2485 | ||
2486 | static DEFINE_MUTEX(graph_lock); | |
2487 | ||
2488 | int ftrace_graph_count; | |
2489 | unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; | |
2490 | ||
2491 | static void * | |
2492 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
2493 | { | |
2494 | unsigned long *array = m->private; | |
2495 | int index = *pos; | |
2496 | ||
2497 | (*pos)++; | |
2498 | ||
2499 | if (index >= ftrace_graph_count) | |
2500 | return NULL; | |
2501 | ||
2502 | return &array[index]; | |
2503 | } | |
2504 | ||
2505 | static void *g_start(struct seq_file *m, loff_t *pos) | |
2506 | { | |
2507 | void *p = NULL; | |
2508 | ||
2509 | mutex_lock(&graph_lock); | |
2510 | ||
f9349a8f FW |
2511 | /* Nothing, tell g_show to print all functions are enabled */ |
2512 | if (!ftrace_graph_count && !*pos) | |
2513 | return (void *)1; | |
2514 | ||
ea4e2bc4 SR |
2515 | p = g_next(m, p, pos); |
2516 | ||
2517 | return p; | |
2518 | } | |
2519 | ||
2520 | static void g_stop(struct seq_file *m, void *p) | |
2521 | { | |
2522 | mutex_unlock(&graph_lock); | |
2523 | } | |
2524 | ||
2525 | static int g_show(struct seq_file *m, void *v) | |
2526 | { | |
2527 | unsigned long *ptr = v; | |
2528 | char str[KSYM_SYMBOL_LEN]; | |
2529 | ||
2530 | if (!ptr) | |
2531 | return 0; | |
2532 | ||
f9349a8f FW |
2533 | if (ptr == (unsigned long *)1) { |
2534 | seq_printf(m, "#### all functions enabled ####\n"); | |
2535 | return 0; | |
2536 | } | |
2537 | ||
ea4e2bc4 SR |
2538 | kallsyms_lookup(*ptr, NULL, NULL, NULL, str); |
2539 | ||
2540 | seq_printf(m, "%s\n", str); | |
2541 | ||
2542 | return 0; | |
2543 | } | |
2544 | ||
2545 | static struct seq_operations ftrace_graph_seq_ops = { | |
2546 | .start = g_start, | |
2547 | .next = g_next, | |
2548 | .stop = g_stop, | |
2549 | .show = g_show, | |
2550 | }; | |
2551 | ||
2552 | static int | |
2553 | ftrace_graph_open(struct inode *inode, struct file *file) | |
2554 | { | |
2555 | int ret = 0; | |
2556 | ||
2557 | if (unlikely(ftrace_disabled)) | |
2558 | return -ENODEV; | |
2559 | ||
2560 | mutex_lock(&graph_lock); | |
2561 | if ((file->f_mode & FMODE_WRITE) && | |
2562 | !(file->f_flags & O_APPEND)) { | |
2563 | ftrace_graph_count = 0; | |
2564 | memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); | |
2565 | } | |
2566 | ||
2567 | if (file->f_mode & FMODE_READ) { | |
2568 | ret = seq_open(file, &ftrace_graph_seq_ops); | |
2569 | if (!ret) { | |
2570 | struct seq_file *m = file->private_data; | |
2571 | m->private = ftrace_graph_funcs; | |
2572 | } | |
2573 | } else | |
2574 | file->private_data = ftrace_graph_funcs; | |
2575 | mutex_unlock(&graph_lock); | |
2576 | ||
2577 | return ret; | |
2578 | } | |
2579 | ||
ea4e2bc4 | 2580 | static int |
f9349a8f | 2581 | ftrace_set_func(unsigned long *array, int *idx, char *buffer) |
ea4e2bc4 | 2582 | { |
ea4e2bc4 SR |
2583 | struct dyn_ftrace *rec; |
2584 | struct ftrace_page *pg; | |
f9349a8f | 2585 | int search_len; |
ea4e2bc4 | 2586 | int found = 0; |
f9349a8f FW |
2587 | int type, not; |
2588 | char *search; | |
2589 | bool exists; | |
2590 | int i; | |
ea4e2bc4 SR |
2591 | |
2592 | if (ftrace_disabled) | |
2593 | return -ENODEV; | |
2594 | ||
f9349a8f FW |
2595 | /* decode regex */ |
2596 | type = ftrace_setup_glob(buffer, strlen(buffer), &search, ¬); | |
2597 | if (not) | |
2598 | return -EINVAL; | |
2599 | ||
2600 | search_len = strlen(search); | |
2601 | ||
52baf119 | 2602 | mutex_lock(&ftrace_lock); |
265c831c SR |
2603 | do_for_each_ftrace_rec(pg, rec) { |
2604 | ||
f9349a8f FW |
2605 | if (*idx >= FTRACE_GRAPH_MAX_FUNCS) |
2606 | break; | |
2607 | ||
265c831c SR |
2608 | if (rec->flags & (FTRACE_FL_FAILED | FTRACE_FL_FREE)) |
2609 | continue; | |
2610 | ||
f9349a8f FW |
2611 | if (ftrace_match_record(rec, search, search_len, type)) { |
2612 | /* ensure it is not already in the array */ | |
2613 | exists = false; | |
2614 | for (i = 0; i < *idx; i++) | |
2615 | if (array[i] == rec->ip) { | |
2616 | exists = true; | |
265c831c SR |
2617 | break; |
2618 | } | |
f9349a8f FW |
2619 | if (!exists) { |
2620 | array[(*idx)++] = rec->ip; | |
2621 | found = 1; | |
2622 | } | |
ea4e2bc4 | 2623 | } |
265c831c | 2624 | } while_for_each_ftrace_rec(); |
f9349a8f | 2625 | |
52baf119 | 2626 | mutex_unlock(&ftrace_lock); |
ea4e2bc4 SR |
2627 | |
2628 | return found ? 0 : -EINVAL; | |
2629 | } | |
2630 | ||
2631 | static ssize_t | |
2632 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
2633 | size_t cnt, loff_t *ppos) | |
2634 | { | |
2635 | unsigned char buffer[FTRACE_BUFF_MAX+1]; | |
2636 | unsigned long *array; | |
2637 | size_t read = 0; | |
2638 | ssize_t ret; | |
2639 | int index = 0; | |
2640 | char ch; | |
2641 | ||
2642 | if (!cnt || cnt < 0) | |
2643 | return 0; | |
2644 | ||
2645 | mutex_lock(&graph_lock); | |
2646 | ||
2647 | if (ftrace_graph_count >= FTRACE_GRAPH_MAX_FUNCS) { | |
2648 | ret = -EBUSY; | |
2649 | goto out; | |
2650 | } | |
2651 | ||
2652 | if (file->f_mode & FMODE_READ) { | |
2653 | struct seq_file *m = file->private_data; | |
2654 | array = m->private; | |
2655 | } else | |
2656 | array = file->private_data; | |
2657 | ||
2658 | ret = get_user(ch, ubuf++); | |
2659 | if (ret) | |
2660 | goto out; | |
2661 | read++; | |
2662 | cnt--; | |
2663 | ||
2664 | /* skip white space */ | |
2665 | while (cnt && isspace(ch)) { | |
2666 | ret = get_user(ch, ubuf++); | |
2667 | if (ret) | |
2668 | goto out; | |
2669 | read++; | |
2670 | cnt--; | |
2671 | } | |
2672 | ||
2673 | if (isspace(ch)) { | |
2674 | *ppos += read; | |
2675 | ret = read; | |
2676 | goto out; | |
2677 | } | |
2678 | ||
2679 | while (cnt && !isspace(ch)) { | |
2680 | if (index < FTRACE_BUFF_MAX) | |
2681 | buffer[index++] = ch; | |
2682 | else { | |
2683 | ret = -EINVAL; | |
2684 | goto out; | |
2685 | } | |
2686 | ret = get_user(ch, ubuf++); | |
2687 | if (ret) | |
2688 | goto out; | |
2689 | read++; | |
2690 | cnt--; | |
2691 | } | |
2692 | buffer[index] = 0; | |
2693 | ||
f9349a8f FW |
2694 | /* we allow only one expression at a time */ |
2695 | ret = ftrace_set_func(array, &ftrace_graph_count, buffer); | |
ea4e2bc4 SR |
2696 | if (ret) |
2697 | goto out; | |
2698 | ||
ea4e2bc4 SR |
2699 | file->f_pos += read; |
2700 | ||
2701 | ret = read; | |
2702 | out: | |
2703 | mutex_unlock(&graph_lock); | |
2704 | ||
2705 | return ret; | |
2706 | } | |
2707 | ||
2708 | static const struct file_operations ftrace_graph_fops = { | |
2709 | .open = ftrace_graph_open, | |
850a80cf | 2710 | .read = seq_read, |
ea4e2bc4 SR |
2711 | .write = ftrace_graph_write, |
2712 | }; | |
2713 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
2714 | ||
df4fc315 | 2715 | static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) |
5072c59f | 2716 | { |
5072c59f | 2717 | |
5452af66 FW |
2718 | trace_create_file("available_filter_functions", 0444, |
2719 | d_tracer, NULL, &ftrace_avail_fops); | |
5072c59f | 2720 | |
5452af66 FW |
2721 | trace_create_file("failures", 0444, |
2722 | d_tracer, NULL, &ftrace_failures_fops); | |
eb9a7bf0 | 2723 | |
5452af66 FW |
2724 | trace_create_file("set_ftrace_filter", 0644, d_tracer, |
2725 | NULL, &ftrace_filter_fops); | |
41c52c0d | 2726 | |
5452af66 | 2727 | trace_create_file("set_ftrace_notrace", 0644, d_tracer, |
41c52c0d | 2728 | NULL, &ftrace_notrace_fops); |
ad90c0e3 | 2729 | |
ea4e2bc4 | 2730 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5452af66 | 2731 | trace_create_file("set_graph_function", 0444, d_tracer, |
ea4e2bc4 SR |
2732 | NULL, |
2733 | &ftrace_graph_fops); | |
ea4e2bc4 SR |
2734 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
2735 | ||
5072c59f SR |
2736 | return 0; |
2737 | } | |
2738 | ||
31e88909 SR |
2739 | static int ftrace_convert_nops(struct module *mod, |
2740 | unsigned long *start, | |
68bf21aa SR |
2741 | unsigned long *end) |
2742 | { | |
2743 | unsigned long *p; | |
2744 | unsigned long addr; | |
2745 | unsigned long flags; | |
2746 | ||
e6ea44e9 | 2747 | mutex_lock(&ftrace_lock); |
68bf21aa SR |
2748 | p = start; |
2749 | while (p < end) { | |
2750 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
2751 | /* |
2752 | * Some architecture linkers will pad between | |
2753 | * the different mcount_loc sections of different | |
2754 | * object files to satisfy alignments. | |
2755 | * Skip any NULL pointers. | |
2756 | */ | |
2757 | if (!addr) | |
2758 | continue; | |
68bf21aa | 2759 | ftrace_record_ip(addr); |
68bf21aa SR |
2760 | } |
2761 | ||
08f5ac90 | 2762 | /* disable interrupts to prevent kstop machine */ |
68bf21aa | 2763 | local_irq_save(flags); |
31e88909 | 2764 | ftrace_update_code(mod); |
68bf21aa | 2765 | local_irq_restore(flags); |
e6ea44e9 | 2766 | mutex_unlock(&ftrace_lock); |
68bf21aa SR |
2767 | |
2768 | return 0; | |
2769 | } | |
2770 | ||
93eb677d SR |
2771 | #ifdef CONFIG_MODULES |
2772 | void ftrace_release(void *start, void *end) | |
2773 | { | |
2774 | struct dyn_ftrace *rec; | |
2775 | struct ftrace_page *pg; | |
2776 | unsigned long s = (unsigned long)start; | |
2777 | unsigned long e = (unsigned long)end; | |
2778 | ||
2779 | if (ftrace_disabled || !start || start == end) | |
2780 | return; | |
2781 | ||
2782 | mutex_lock(&ftrace_lock); | |
2783 | do_for_each_ftrace_rec(pg, rec) { | |
2784 | if ((rec->ip >= s) && (rec->ip < e)) { | |
2785 | /* | |
2786 | * rec->ip is changed in ftrace_free_rec() | |
2787 | * It should not between s and e if record was freed. | |
2788 | */ | |
2789 | FTRACE_WARN_ON(rec->flags & FTRACE_FL_FREE); | |
2790 | ftrace_free_rec(rec); | |
2791 | } | |
2792 | } while_for_each_ftrace_rec(); | |
2793 | mutex_unlock(&ftrace_lock); | |
2794 | } | |
2795 | ||
2796 | static void ftrace_init_module(struct module *mod, | |
2797 | unsigned long *start, unsigned long *end) | |
90d595fe | 2798 | { |
00fd61ae | 2799 | if (ftrace_disabled || start == end) |
fed1939c | 2800 | return; |
31e88909 | 2801 | ftrace_convert_nops(mod, start, end); |
90d595fe SR |
2802 | } |
2803 | ||
93eb677d SR |
2804 | static int ftrace_module_notify(struct notifier_block *self, |
2805 | unsigned long val, void *data) | |
2806 | { | |
2807 | struct module *mod = data; | |
2808 | ||
2809 | switch (val) { | |
2810 | case MODULE_STATE_COMING: | |
2811 | ftrace_init_module(mod, mod->ftrace_callsites, | |
2812 | mod->ftrace_callsites + | |
2813 | mod->num_ftrace_callsites); | |
2814 | break; | |
2815 | case MODULE_STATE_GOING: | |
2816 | ftrace_release(mod->ftrace_callsites, | |
2817 | mod->ftrace_callsites + | |
2818 | mod->num_ftrace_callsites); | |
2819 | break; | |
2820 | } | |
2821 | ||
2822 | return 0; | |
2823 | } | |
2824 | #else | |
2825 | static int ftrace_module_notify(struct notifier_block *self, | |
2826 | unsigned long val, void *data) | |
2827 | { | |
2828 | return 0; | |
2829 | } | |
2830 | #endif /* CONFIG_MODULES */ | |
2831 | ||
2832 | struct notifier_block ftrace_module_nb = { | |
2833 | .notifier_call = ftrace_module_notify, | |
2834 | .priority = 0, | |
2835 | }; | |
2836 | ||
68bf21aa SR |
2837 | extern unsigned long __start_mcount_loc[]; |
2838 | extern unsigned long __stop_mcount_loc[]; | |
2839 | ||
2840 | void __init ftrace_init(void) | |
2841 | { | |
2842 | unsigned long count, addr, flags; | |
2843 | int ret; | |
2844 | ||
2845 | /* Keep the ftrace pointer to the stub */ | |
2846 | addr = (unsigned long)ftrace_stub; | |
2847 | ||
2848 | local_irq_save(flags); | |
2849 | ftrace_dyn_arch_init(&addr); | |
2850 | local_irq_restore(flags); | |
2851 | ||
2852 | /* ftrace_dyn_arch_init places the return code in addr */ | |
2853 | if (addr) | |
2854 | goto failed; | |
2855 | ||
2856 | count = __stop_mcount_loc - __start_mcount_loc; | |
2857 | ||
2858 | ret = ftrace_dyn_table_alloc(count); | |
2859 | if (ret) | |
2860 | goto failed; | |
2861 | ||
2862 | last_ftrace_enabled = ftrace_enabled = 1; | |
2863 | ||
31e88909 SR |
2864 | ret = ftrace_convert_nops(NULL, |
2865 | __start_mcount_loc, | |
68bf21aa SR |
2866 | __stop_mcount_loc); |
2867 | ||
93eb677d | 2868 | ret = register_module_notifier(&ftrace_module_nb); |
24ed0c4b | 2869 | if (ret) |
93eb677d SR |
2870 | pr_warning("Failed to register trace ftrace module notifier\n"); |
2871 | ||
2af15d6a SR |
2872 | set_ftrace_early_filters(); |
2873 | ||
68bf21aa SR |
2874 | return; |
2875 | failed: | |
2876 | ftrace_disabled = 1; | |
2877 | } | |
68bf21aa | 2878 | |
3d083395 | 2879 | #else |
0b6e4d56 FW |
2880 | |
2881 | static int __init ftrace_nodyn_init(void) | |
2882 | { | |
2883 | ftrace_enabled = 1; | |
2884 | return 0; | |
2885 | } | |
2886 | device_initcall(ftrace_nodyn_init); | |
2887 | ||
df4fc315 SR |
2888 | static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } |
2889 | static inline void ftrace_startup_enable(int command) { } | |
5a45cfe1 SR |
2890 | /* Keep as macros so we do not need to define the commands */ |
2891 | # define ftrace_startup(command) do { } while (0) | |
2892 | # define ftrace_shutdown(command) do { } while (0) | |
c7aafc54 IM |
2893 | # define ftrace_startup_sysctl() do { } while (0) |
2894 | # define ftrace_shutdown_sysctl() do { } while (0) | |
3d083395 SR |
2895 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
2896 | ||
df4fc315 SR |
2897 | static ssize_t |
2898 | ftrace_pid_read(struct file *file, char __user *ubuf, | |
2899 | size_t cnt, loff_t *ppos) | |
2900 | { | |
2901 | char buf[64]; | |
2902 | int r; | |
2903 | ||
e32d8956 SR |
2904 | if (ftrace_pid_trace == ftrace_swapper_pid) |
2905 | r = sprintf(buf, "swapper tasks\n"); | |
2906 | else if (ftrace_pid_trace) | |
cc59c9e8 | 2907 | r = sprintf(buf, "%u\n", pid_vnr(ftrace_pid_trace)); |
df4fc315 SR |
2908 | else |
2909 | r = sprintf(buf, "no pid\n"); | |
2910 | ||
2911 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
2912 | } | |
2913 | ||
e32d8956 | 2914 | static void clear_ftrace_swapper(void) |
978f3a45 SR |
2915 | { |
2916 | struct task_struct *p; | |
e32d8956 | 2917 | int cpu; |
978f3a45 | 2918 | |
e32d8956 SR |
2919 | get_online_cpus(); |
2920 | for_each_online_cpu(cpu) { | |
2921 | p = idle_task(cpu); | |
978f3a45 | 2922 | clear_tsk_trace_trace(p); |
e32d8956 SR |
2923 | } |
2924 | put_online_cpus(); | |
2925 | } | |
978f3a45 | 2926 | |
e32d8956 SR |
2927 | static void set_ftrace_swapper(void) |
2928 | { | |
2929 | struct task_struct *p; | |
2930 | int cpu; | |
2931 | ||
2932 | get_online_cpus(); | |
2933 | for_each_online_cpu(cpu) { | |
2934 | p = idle_task(cpu); | |
2935 | set_tsk_trace_trace(p); | |
2936 | } | |
2937 | put_online_cpus(); | |
978f3a45 SR |
2938 | } |
2939 | ||
e32d8956 SR |
2940 | static void clear_ftrace_pid(struct pid *pid) |
2941 | { | |
2942 | struct task_struct *p; | |
2943 | ||
229c4ef8 | 2944 | rcu_read_lock(); |
e32d8956 SR |
2945 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
2946 | clear_tsk_trace_trace(p); | |
2947 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 ON |
2948 | rcu_read_unlock(); |
2949 | ||
e32d8956 SR |
2950 | put_pid(pid); |
2951 | } | |
2952 | ||
2953 | static void set_ftrace_pid(struct pid *pid) | |
978f3a45 SR |
2954 | { |
2955 | struct task_struct *p; | |
2956 | ||
229c4ef8 | 2957 | rcu_read_lock(); |
978f3a45 SR |
2958 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
2959 | set_tsk_trace_trace(p); | |
2960 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 | 2961 | rcu_read_unlock(); |
978f3a45 SR |
2962 | } |
2963 | ||
e32d8956 SR |
2964 | static void clear_ftrace_pid_task(struct pid **pid) |
2965 | { | |
2966 | if (*pid == ftrace_swapper_pid) | |
2967 | clear_ftrace_swapper(); | |
2968 | else | |
2969 | clear_ftrace_pid(*pid); | |
2970 | ||
2971 | *pid = NULL; | |
2972 | } | |
2973 | ||
2974 | static void set_ftrace_pid_task(struct pid *pid) | |
2975 | { | |
2976 | if (pid == ftrace_swapper_pid) | |
2977 | set_ftrace_swapper(); | |
2978 | else | |
2979 | set_ftrace_pid(pid); | |
2980 | } | |
2981 | ||
df4fc315 SR |
2982 | static ssize_t |
2983 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
2984 | size_t cnt, loff_t *ppos) | |
2985 | { | |
978f3a45 | 2986 | struct pid *pid; |
df4fc315 SR |
2987 | char buf[64]; |
2988 | long val; | |
2989 | int ret; | |
2990 | ||
2991 | if (cnt >= sizeof(buf)) | |
2992 | return -EINVAL; | |
2993 | ||
2994 | if (copy_from_user(&buf, ubuf, cnt)) | |
2995 | return -EFAULT; | |
2996 | ||
2997 | buf[cnt] = 0; | |
2998 | ||
2999 | ret = strict_strtol(buf, 10, &val); | |
3000 | if (ret < 0) | |
3001 | return ret; | |
3002 | ||
e6ea44e9 | 3003 | mutex_lock(&ftrace_lock); |
978f3a45 | 3004 | if (val < 0) { |
df4fc315 | 3005 | /* disable pid tracing */ |
978f3a45 | 3006 | if (!ftrace_pid_trace) |
df4fc315 | 3007 | goto out; |
978f3a45 SR |
3008 | |
3009 | clear_ftrace_pid_task(&ftrace_pid_trace); | |
df4fc315 SR |
3010 | |
3011 | } else { | |
e32d8956 SR |
3012 | /* swapper task is special */ |
3013 | if (!val) { | |
3014 | pid = ftrace_swapper_pid; | |
3015 | if (pid == ftrace_pid_trace) | |
3016 | goto out; | |
3017 | } else { | |
3018 | pid = find_get_pid(val); | |
df4fc315 | 3019 | |
e32d8956 SR |
3020 | if (pid == ftrace_pid_trace) { |
3021 | put_pid(pid); | |
3022 | goto out; | |
3023 | } | |
0ef8cde5 | 3024 | } |
0ef8cde5 | 3025 | |
978f3a45 SR |
3026 | if (ftrace_pid_trace) |
3027 | clear_ftrace_pid_task(&ftrace_pid_trace); | |
3028 | ||
3029 | if (!pid) | |
3030 | goto out; | |
3031 | ||
3032 | ftrace_pid_trace = pid; | |
3033 | ||
3034 | set_ftrace_pid_task(ftrace_pid_trace); | |
df4fc315 SR |
3035 | } |
3036 | ||
3037 | /* update the function call */ | |
3038 | ftrace_update_pid_func(); | |
3039 | ftrace_startup_enable(0); | |
3040 | ||
3041 | out: | |
e6ea44e9 | 3042 | mutex_unlock(&ftrace_lock); |
df4fc315 SR |
3043 | |
3044 | return cnt; | |
3045 | } | |
3046 | ||
5e2336a0 | 3047 | static const struct file_operations ftrace_pid_fops = { |
df4fc315 SR |
3048 | .read = ftrace_pid_read, |
3049 | .write = ftrace_pid_write, | |
3050 | }; | |
3051 | ||
3052 | static __init int ftrace_init_debugfs(void) | |
3053 | { | |
3054 | struct dentry *d_tracer; | |
df4fc315 SR |
3055 | |
3056 | d_tracer = tracing_init_dentry(); | |
3057 | if (!d_tracer) | |
3058 | return 0; | |
3059 | ||
3060 | ftrace_init_dyn_debugfs(d_tracer); | |
3061 | ||
5452af66 FW |
3062 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
3063 | NULL, &ftrace_pid_fops); | |
493762fc SR |
3064 | |
3065 | ftrace_profile_debugfs(d_tracer); | |
3066 | ||
df4fc315 SR |
3067 | return 0; |
3068 | } | |
df4fc315 SR |
3069 | fs_initcall(ftrace_init_debugfs); |
3070 | ||
a2bb6a3d | 3071 | /** |
81adbdc0 | 3072 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
3073 | * |
3074 | * This function should be used by panic code. It stops ftrace | |
3075 | * but in a not so nice way. If you need to simply kill ftrace | |
3076 | * from a non-atomic section, use ftrace_kill. | |
3077 | */ | |
81adbdc0 | 3078 | void ftrace_kill(void) |
a2bb6a3d SR |
3079 | { |
3080 | ftrace_disabled = 1; | |
3081 | ftrace_enabled = 0; | |
a2bb6a3d SR |
3082 | clear_ftrace_function(); |
3083 | } | |
3084 | ||
16444a8a | 3085 | /** |
3d083395 SR |
3086 | * register_ftrace_function - register a function for profiling |
3087 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 3088 | * |
3d083395 SR |
3089 | * Register a function to be called by all functions in the |
3090 | * kernel. | |
3091 | * | |
3092 | * Note: @ops->func and all the functions it calls must be labeled | |
3093 | * with "notrace", otherwise it will go into a | |
3094 | * recursive loop. | |
16444a8a | 3095 | */ |
3d083395 | 3096 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 3097 | { |
b0fc494f SR |
3098 | int ret; |
3099 | ||
4eebcc81 SR |
3100 | if (unlikely(ftrace_disabled)) |
3101 | return -1; | |
3102 | ||
e6ea44e9 | 3103 | mutex_lock(&ftrace_lock); |
e7d3737e | 3104 | |
b0fc494f | 3105 | ret = __register_ftrace_function(ops); |
5a45cfe1 | 3106 | ftrace_startup(0); |
b0fc494f | 3107 | |
e6ea44e9 | 3108 | mutex_unlock(&ftrace_lock); |
b0fc494f | 3109 | return ret; |
3d083395 SR |
3110 | } |
3111 | ||
3112 | /** | |
32632920 | 3113 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
3114 | * @ops - ops structure that holds the function to unregister |
3115 | * | |
3116 | * Unregister a function that was added to be called by ftrace profiling. | |
3117 | */ | |
3118 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
3119 | { | |
3120 | int ret; | |
3121 | ||
e6ea44e9 | 3122 | mutex_lock(&ftrace_lock); |
3d083395 | 3123 | ret = __unregister_ftrace_function(ops); |
5a45cfe1 | 3124 | ftrace_shutdown(0); |
e6ea44e9 | 3125 | mutex_unlock(&ftrace_lock); |
b0fc494f SR |
3126 | |
3127 | return ret; | |
3128 | } | |
3129 | ||
e309b41d | 3130 | int |
b0fc494f | 3131 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
5072c59f | 3132 | struct file *file, void __user *buffer, size_t *lenp, |
b0fc494f SR |
3133 | loff_t *ppos) |
3134 | { | |
3135 | int ret; | |
3136 | ||
4eebcc81 SR |
3137 | if (unlikely(ftrace_disabled)) |
3138 | return -ENODEV; | |
3139 | ||
e6ea44e9 | 3140 | mutex_lock(&ftrace_lock); |
b0fc494f | 3141 | |
5072c59f | 3142 | ret = proc_dointvec(table, write, file, buffer, lenp, ppos); |
b0fc494f SR |
3143 | |
3144 | if (ret || !write || (last_ftrace_enabled == ftrace_enabled)) | |
3145 | goto out; | |
3146 | ||
3147 | last_ftrace_enabled = ftrace_enabled; | |
3148 | ||
3149 | if (ftrace_enabled) { | |
3150 | ||
3151 | ftrace_startup_sysctl(); | |
3152 | ||
3153 | /* we are starting ftrace again */ | |
3154 | if (ftrace_list != &ftrace_list_end) { | |
3155 | if (ftrace_list->next == &ftrace_list_end) | |
3156 | ftrace_trace_function = ftrace_list->func; | |
3157 | else | |
3158 | ftrace_trace_function = ftrace_list_func; | |
3159 | } | |
3160 | ||
3161 | } else { | |
3162 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
3163 | ftrace_trace_function = ftrace_stub; | |
3164 | ||
3165 | ftrace_shutdown_sysctl(); | |
3166 | } | |
3167 | ||
3168 | out: | |
e6ea44e9 | 3169 | mutex_unlock(&ftrace_lock); |
3d083395 | 3170 | return ret; |
16444a8a | 3171 | } |
f17845e5 | 3172 | |
fb52607a | 3173 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 3174 | |
597af815 | 3175 | static int ftrace_graph_active; |
4a2b8dda | 3176 | static struct notifier_block ftrace_suspend_notifier; |
e7d3737e | 3177 | |
e49dc19c SR |
3178 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
3179 | { | |
3180 | return 0; | |
3181 | } | |
3182 | ||
287b6e68 FW |
3183 | /* The callbacks that hook a function */ |
3184 | trace_func_graph_ret_t ftrace_graph_return = | |
3185 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 3186 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
3187 | |
3188 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
3189 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
3190 | { | |
3191 | int i; | |
3192 | int ret = 0; | |
3193 | unsigned long flags; | |
3194 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; | |
3195 | struct task_struct *g, *t; | |
3196 | ||
3197 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
3198 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
3199 | * sizeof(struct ftrace_ret_stack), | |
3200 | GFP_KERNEL); | |
3201 | if (!ret_stack_list[i]) { | |
3202 | start = 0; | |
3203 | end = i; | |
3204 | ret = -ENOMEM; | |
3205 | goto free; | |
3206 | } | |
3207 | } | |
3208 | ||
3209 | read_lock_irqsave(&tasklist_lock, flags); | |
3210 | do_each_thread(g, t) { | |
3211 | if (start == end) { | |
3212 | ret = -EAGAIN; | |
3213 | goto unlock; | |
3214 | } | |
3215 | ||
3216 | if (t->ret_stack == NULL) { | |
f201ae23 | 3217 | t->curr_ret_stack = -1; |
48d68b20 FW |
3218 | /* Make sure IRQs see the -1 first: */ |
3219 | barrier(); | |
3220 | t->ret_stack = ret_stack_list[start++]; | |
380c4b14 | 3221 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 FW |
3222 | atomic_set(&t->trace_overrun, 0); |
3223 | } | |
3224 | } while_each_thread(g, t); | |
3225 | ||
3226 | unlock: | |
3227 | read_unlock_irqrestore(&tasklist_lock, flags); | |
3228 | free: | |
3229 | for (i = start; i < end; i++) | |
3230 | kfree(ret_stack_list[i]); | |
3231 | return ret; | |
3232 | } | |
3233 | ||
8aef2d28 SR |
3234 | static void |
3235 | ftrace_graph_probe_sched_switch(struct rq *__rq, struct task_struct *prev, | |
3236 | struct task_struct *next) | |
3237 | { | |
3238 | unsigned long long timestamp; | |
3239 | int index; | |
3240 | ||
be6f164a SR |
3241 | /* |
3242 | * Does the user want to count the time a function was asleep. | |
3243 | * If so, do not update the time stamps. | |
3244 | */ | |
3245 | if (trace_flags & TRACE_ITER_SLEEP_TIME) | |
3246 | return; | |
3247 | ||
8aef2d28 SR |
3248 | timestamp = trace_clock_local(); |
3249 | ||
3250 | prev->ftrace_timestamp = timestamp; | |
3251 | ||
3252 | /* only process tasks that we timestamped */ | |
3253 | if (!next->ftrace_timestamp) | |
3254 | return; | |
3255 | ||
3256 | /* | |
3257 | * Update all the counters in next to make up for the | |
3258 | * time next was sleeping. | |
3259 | */ | |
3260 | timestamp -= next->ftrace_timestamp; | |
3261 | ||
3262 | for (index = next->curr_ret_stack; index >= 0; index--) | |
3263 | next->ret_stack[index].calltime += timestamp; | |
3264 | } | |
3265 | ||
f201ae23 | 3266 | /* Allocate a return stack for each task */ |
fb52607a | 3267 | static int start_graph_tracing(void) |
f201ae23 FW |
3268 | { |
3269 | struct ftrace_ret_stack **ret_stack_list; | |
5b058bcd | 3270 | int ret, cpu; |
f201ae23 FW |
3271 | |
3272 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
3273 | sizeof(struct ftrace_ret_stack *), | |
3274 | GFP_KERNEL); | |
3275 | ||
3276 | if (!ret_stack_list) | |
3277 | return -ENOMEM; | |
3278 | ||
5b058bcd FW |
3279 | /* The cpu_boot init_task->ret_stack will never be freed */ |
3280 | for_each_online_cpu(cpu) | |
3281 | ftrace_graph_init_task(idle_task(cpu)); | |
3282 | ||
f201ae23 FW |
3283 | do { |
3284 | ret = alloc_retstack_tasklist(ret_stack_list); | |
3285 | } while (ret == -EAGAIN); | |
3286 | ||
8aef2d28 SR |
3287 | if (!ret) { |
3288 | ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch); | |
3289 | if (ret) | |
3290 | pr_info("ftrace_graph: Couldn't activate tracepoint" | |
3291 | " probe to kernel_sched_switch\n"); | |
3292 | } | |
3293 | ||
f201ae23 FW |
3294 | kfree(ret_stack_list); |
3295 | return ret; | |
3296 | } | |
3297 | ||
4a2b8dda FW |
3298 | /* |
3299 | * Hibernation protection. | |
3300 | * The state of the current task is too much unstable during | |
3301 | * suspend/restore to disk. We want to protect against that. | |
3302 | */ | |
3303 | static int | |
3304 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, | |
3305 | void *unused) | |
3306 | { | |
3307 | switch (state) { | |
3308 | case PM_HIBERNATION_PREPARE: | |
3309 | pause_graph_tracing(); | |
3310 | break; | |
3311 | ||
3312 | case PM_POST_HIBERNATION: | |
3313 | unpause_graph_tracing(); | |
3314 | break; | |
3315 | } | |
3316 | return NOTIFY_DONE; | |
3317 | } | |
3318 | ||
287b6e68 FW |
3319 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
3320 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 3321 | { |
e7d3737e FW |
3322 | int ret = 0; |
3323 | ||
e6ea44e9 | 3324 | mutex_lock(&ftrace_lock); |
e7d3737e | 3325 | |
05ce5818 | 3326 | /* we currently allow only one tracer registered at a time */ |
597af815 | 3327 | if (ftrace_graph_active) { |
05ce5818 SR |
3328 | ret = -EBUSY; |
3329 | goto out; | |
3330 | } | |
3331 | ||
4a2b8dda FW |
3332 | ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call; |
3333 | register_pm_notifier(&ftrace_suspend_notifier); | |
3334 | ||
597af815 | 3335 | ftrace_graph_active++; |
fb52607a | 3336 | ret = start_graph_tracing(); |
f201ae23 | 3337 | if (ret) { |
597af815 | 3338 | ftrace_graph_active--; |
f201ae23 FW |
3339 | goto out; |
3340 | } | |
e53a6319 | 3341 | |
287b6e68 FW |
3342 | ftrace_graph_return = retfunc; |
3343 | ftrace_graph_entry = entryfunc; | |
e53a6319 | 3344 | |
5a45cfe1 | 3345 | ftrace_startup(FTRACE_START_FUNC_RET); |
e7d3737e FW |
3346 | |
3347 | out: | |
e6ea44e9 | 3348 | mutex_unlock(&ftrace_lock); |
e7d3737e | 3349 | return ret; |
15e6cb36 FW |
3350 | } |
3351 | ||
fb52607a | 3352 | void unregister_ftrace_graph(void) |
15e6cb36 | 3353 | { |
e6ea44e9 | 3354 | mutex_lock(&ftrace_lock); |
e7d3737e | 3355 | |
597af815 | 3356 | if (unlikely(!ftrace_graph_active)) |
2aad1b76 SR |
3357 | goto out; |
3358 | ||
597af815 | 3359 | ftrace_graph_active--; |
8aef2d28 | 3360 | unregister_trace_sched_switch(ftrace_graph_probe_sched_switch); |
287b6e68 | 3361 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; |
e49dc19c | 3362 | ftrace_graph_entry = ftrace_graph_entry_stub; |
5a45cfe1 | 3363 | ftrace_shutdown(FTRACE_STOP_FUNC_RET); |
4a2b8dda | 3364 | unregister_pm_notifier(&ftrace_suspend_notifier); |
e7d3737e | 3365 | |
2aad1b76 | 3366 | out: |
e6ea44e9 | 3367 | mutex_unlock(&ftrace_lock); |
15e6cb36 | 3368 | } |
f201ae23 FW |
3369 | |
3370 | /* Allocate a return stack for newly created task */ | |
fb52607a | 3371 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 3372 | { |
597af815 | 3373 | if (ftrace_graph_active) { |
f201ae23 FW |
3374 | t->ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH |
3375 | * sizeof(struct ftrace_ret_stack), | |
3376 | GFP_KERNEL); | |
3377 | if (!t->ret_stack) | |
3378 | return; | |
3379 | t->curr_ret_stack = -1; | |
380c4b14 | 3380 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 | 3381 | atomic_set(&t->trace_overrun, 0); |
8aef2d28 | 3382 | t->ftrace_timestamp = 0; |
f201ae23 FW |
3383 | } else |
3384 | t->ret_stack = NULL; | |
3385 | } | |
3386 | ||
fb52607a | 3387 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 3388 | { |
eae849ca FW |
3389 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
3390 | ||
f201ae23 | 3391 | t->ret_stack = NULL; |
eae849ca FW |
3392 | /* NULL must become visible to IRQs before we free it: */ |
3393 | barrier(); | |
3394 | ||
3395 | kfree(ret_stack); | |
f201ae23 | 3396 | } |
14a866c5 SR |
3397 | |
3398 | void ftrace_graph_stop(void) | |
3399 | { | |
3400 | ftrace_stop(); | |
3401 | } | |
15e6cb36 FW |
3402 | #endif |
3403 |