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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> |
56d82e00 | 25 | #include <linux/module.h> |
2d8b820b | 26 | #include <linux/ftrace.h> |
b0fc494f | 27 | #include <linux/sysctl.h> |
5a0e3ad6 | 28 | #include <linux/slab.h> |
5072c59f | 29 | #include <linux/ctype.h> |
3d083395 | 30 | #include <linux/list.h> |
59df055f | 31 | #include <linux/hash.h> |
3f379b03 | 32 | #include <linux/rcupdate.h> |
3d083395 | 33 | |
ad8d75ff | 34 | #include <trace/events/sched.h> |
8aef2d28 | 35 | |
2af15d6a | 36 | #include <asm/setup.h> |
395a59d0 | 37 | |
0706f1c4 | 38 | #include "trace_output.h" |
bac429f0 | 39 | #include "trace_stat.h" |
16444a8a | 40 | |
6912896e | 41 | #define FTRACE_WARN_ON(cond) \ |
0778d9ad SR |
42 | ({ \ |
43 | int ___r = cond; \ | |
44 | if (WARN_ON(___r)) \ | |
6912896e | 45 | ftrace_kill(); \ |
0778d9ad SR |
46 | ___r; \ |
47 | }) | |
6912896e SR |
48 | |
49 | #define FTRACE_WARN_ON_ONCE(cond) \ | |
0778d9ad SR |
50 | ({ \ |
51 | int ___r = cond; \ | |
52 | if (WARN_ON_ONCE(___r)) \ | |
6912896e | 53 | ftrace_kill(); \ |
0778d9ad SR |
54 | ___r; \ |
55 | }) | |
6912896e | 56 | |
8fc0c701 SR |
57 | /* hash bits for specific function selection */ |
58 | #define FTRACE_HASH_BITS 7 | |
59 | #define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS) | |
33dc9b12 SR |
60 | #define FTRACE_HASH_DEFAULT_BITS 10 |
61 | #define FTRACE_HASH_MAX_BITS 12 | |
8fc0c701 | 62 | |
4eebcc81 SR |
63 | /* ftrace_enabled is a method to turn ftrace on or off */ |
64 | int ftrace_enabled __read_mostly; | |
d61f82d0 | 65 | static int last_ftrace_enabled; |
b0fc494f | 66 | |
60a7ecf4 SR |
67 | /* Quick disabling of function tracer. */ |
68 | int function_trace_stop; | |
69 | ||
756d17ee | 70 | /* List for set_ftrace_pid's pids. */ |
71 | LIST_HEAD(ftrace_pids); | |
72 | struct ftrace_pid { | |
73 | struct list_head list; | |
74 | struct pid *pid; | |
75 | }; | |
76 | ||
4eebcc81 SR |
77 | /* |
78 | * ftrace_disabled is set when an anomaly is discovered. | |
79 | * ftrace_disabled is much stronger than ftrace_enabled. | |
80 | */ | |
81 | static int ftrace_disabled __read_mostly; | |
82 | ||
52baf119 | 83 | static DEFINE_MUTEX(ftrace_lock); |
b0fc494f | 84 | |
bd38c0e6 | 85 | static struct ftrace_ops ftrace_list_end __read_mostly = { |
fb9fb015 | 86 | .func = ftrace_stub, |
16444a8a ACM |
87 | }; |
88 | ||
b848914c SR |
89 | static struct ftrace_ops *ftrace_global_list __read_mostly = &ftrace_list_end; |
90 | static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end; | |
16444a8a | 91 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; |
6331c28c | 92 | static ftrace_func_t __ftrace_trace_function_delay __read_mostly = ftrace_stub; |
60a7ecf4 | 93 | ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub; |
df4fc315 | 94 | ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub; |
2b499381 | 95 | static struct ftrace_ops global_ops; |
16444a8a | 96 | |
b848914c SR |
97 | static void |
98 | ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip); | |
99 | ||
3f379b03 | 100 | /* |
b848914c | 101 | * Traverse the ftrace_global_list, invoking all entries. The reason that we |
3f379b03 PM |
102 | * can use rcu_dereference_raw() is that elements removed from this list |
103 | * are simply leaked, so there is no need to interact with a grace-period | |
104 | * mechanism. The rcu_dereference_raw() calls are needed to handle | |
b848914c | 105 | * concurrent insertions into the ftrace_global_list. |
3f379b03 PM |
106 | * |
107 | * Silly Alpha and silly pointer-speculation compiler optimizations! | |
108 | */ | |
b848914c SR |
109 | static void ftrace_global_list_func(unsigned long ip, |
110 | unsigned long parent_ip) | |
16444a8a | 111 | { |
b1cff0ad SR |
112 | struct ftrace_ops *op; |
113 | ||
114 | if (unlikely(trace_recursion_test(TRACE_GLOBAL_BIT))) | |
115 | return; | |
16444a8a | 116 | |
b1cff0ad SR |
117 | trace_recursion_set(TRACE_GLOBAL_BIT); |
118 | op = rcu_dereference_raw(ftrace_global_list); /*see above*/ | |
16444a8a | 119 | while (op != &ftrace_list_end) { |
16444a8a | 120 | op->func(ip, parent_ip); |
3f379b03 | 121 | op = rcu_dereference_raw(op->next); /*see above*/ |
16444a8a | 122 | }; |
b1cff0ad | 123 | trace_recursion_clear(TRACE_GLOBAL_BIT); |
16444a8a ACM |
124 | } |
125 | ||
df4fc315 SR |
126 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip) |
127 | { | |
0ef8cde5 | 128 | if (!test_tsk_trace_trace(current)) |
df4fc315 SR |
129 | return; |
130 | ||
131 | ftrace_pid_function(ip, parent_ip); | |
132 | } | |
133 | ||
134 | static void set_ftrace_pid_function(ftrace_func_t func) | |
135 | { | |
136 | /* do not set ftrace_pid_function to itself! */ | |
137 | if (func != ftrace_pid_func) | |
138 | ftrace_pid_function = func; | |
139 | } | |
140 | ||
16444a8a | 141 | /** |
3d083395 | 142 | * clear_ftrace_function - reset the ftrace function |
16444a8a | 143 | * |
3d083395 SR |
144 | * This NULLs the ftrace function and in essence stops |
145 | * tracing. There may be lag | |
16444a8a | 146 | */ |
3d083395 | 147 | void clear_ftrace_function(void) |
16444a8a | 148 | { |
3d083395 | 149 | ftrace_trace_function = ftrace_stub; |
60a7ecf4 | 150 | __ftrace_trace_function = ftrace_stub; |
6331c28c | 151 | __ftrace_trace_function_delay = ftrace_stub; |
df4fc315 | 152 | ftrace_pid_function = ftrace_stub; |
3d083395 SR |
153 | } |
154 | ||
60a7ecf4 SR |
155 | #ifndef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
156 | /* | |
157 | * For those archs that do not test ftrace_trace_stop in their | |
158 | * mcount call site, we need to do it from C. | |
159 | */ | |
160 | static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip) | |
161 | { | |
162 | if (function_trace_stop) | |
163 | return; | |
164 | ||
165 | __ftrace_trace_function(ip, parent_ip); | |
166 | } | |
167 | #endif | |
168 | ||
2b499381 | 169 | static void update_global_ops(void) |
491d0dcf SR |
170 | { |
171 | ftrace_func_t func; | |
172 | ||
173 | /* | |
174 | * If there's only one function registered, then call that | |
175 | * function directly. Otherwise, we need to iterate over the | |
176 | * registered callers. | |
177 | */ | |
b848914c SR |
178 | if (ftrace_global_list == &ftrace_list_end || |
179 | ftrace_global_list->next == &ftrace_list_end) | |
180 | func = ftrace_global_list->func; | |
491d0dcf | 181 | else |
b848914c | 182 | func = ftrace_global_list_func; |
491d0dcf SR |
183 | |
184 | /* If we filter on pids, update to use the pid function */ | |
185 | if (!list_empty(&ftrace_pids)) { | |
186 | set_ftrace_pid_function(func); | |
187 | func = ftrace_pid_func; | |
188 | } | |
2b499381 SR |
189 | |
190 | global_ops.func = func; | |
191 | } | |
192 | ||
193 | static void update_ftrace_function(void) | |
194 | { | |
195 | ftrace_func_t func; | |
196 | ||
197 | update_global_ops(); | |
198 | ||
cdbe61bf SR |
199 | /* |
200 | * If we are at the end of the list and this ops is | |
201 | * not dynamic, then have the mcount trampoline call | |
202 | * the function directly | |
203 | */ | |
b848914c | 204 | if (ftrace_ops_list == &ftrace_list_end || |
cdbe61bf SR |
205 | (ftrace_ops_list->next == &ftrace_list_end && |
206 | !(ftrace_ops_list->flags & FTRACE_OPS_FL_DYNAMIC))) | |
b848914c SR |
207 | func = ftrace_ops_list->func; |
208 | else | |
209 | func = ftrace_ops_list_func; | |
2b499381 | 210 | |
491d0dcf SR |
211 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
212 | ftrace_trace_function = func; | |
6331c28c SR |
213 | #else |
214 | #ifdef CONFIG_DYNAMIC_FTRACE | |
215 | /* do not update till all functions have been modified */ | |
216 | __ftrace_trace_function_delay = func; | |
491d0dcf SR |
217 | #else |
218 | __ftrace_trace_function = func; | |
6331c28c | 219 | #endif |
491d0dcf SR |
220 | ftrace_trace_function = ftrace_test_stop_func; |
221 | #endif | |
222 | } | |
223 | ||
2b499381 | 224 | static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
3d083395 | 225 | { |
2b499381 | 226 | ops->next = *list; |
16444a8a | 227 | /* |
b848914c | 228 | * We are entering ops into the list but another |
16444a8a ACM |
229 | * CPU might be walking that list. We need to make sure |
230 | * the ops->next pointer is valid before another CPU sees | |
b848914c | 231 | * the ops pointer included into the list. |
16444a8a | 232 | */ |
2b499381 | 233 | rcu_assign_pointer(*list, ops); |
16444a8a ACM |
234 | } |
235 | ||
2b499381 | 236 | static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
16444a8a | 237 | { |
16444a8a | 238 | struct ftrace_ops **p; |
16444a8a ACM |
239 | |
240 | /* | |
3d083395 SR |
241 | * If we are removing the last function, then simply point |
242 | * to the ftrace_stub. | |
16444a8a | 243 | */ |
2b499381 SR |
244 | if (*list == ops && ops->next == &ftrace_list_end) { |
245 | *list = &ftrace_list_end; | |
e6ea44e9 | 246 | return 0; |
16444a8a ACM |
247 | } |
248 | ||
2b499381 | 249 | for (p = list; *p != &ftrace_list_end; p = &(*p)->next) |
16444a8a ACM |
250 | if (*p == ops) |
251 | break; | |
252 | ||
e6ea44e9 SR |
253 | if (*p != ops) |
254 | return -1; | |
16444a8a ACM |
255 | |
256 | *p = (*p)->next; | |
2b499381 SR |
257 | return 0; |
258 | } | |
16444a8a | 259 | |
2b499381 SR |
260 | static int __register_ftrace_function(struct ftrace_ops *ops) |
261 | { | |
262 | if (ftrace_disabled) | |
263 | return -ENODEV; | |
264 | ||
265 | if (FTRACE_WARN_ON(ops == &global_ops)) | |
266 | return -EINVAL; | |
267 | ||
b848914c SR |
268 | if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED)) |
269 | return -EBUSY; | |
270 | ||
cdbe61bf SR |
271 | if (!core_kernel_data((unsigned long)ops)) |
272 | ops->flags |= FTRACE_OPS_FL_DYNAMIC; | |
273 | ||
b848914c SR |
274 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
275 | int first = ftrace_global_list == &ftrace_list_end; | |
276 | add_ftrace_ops(&ftrace_global_list, ops); | |
277 | ops->flags |= FTRACE_OPS_FL_ENABLED; | |
278 | if (first) | |
279 | add_ftrace_ops(&ftrace_ops_list, &global_ops); | |
280 | } else | |
281 | add_ftrace_ops(&ftrace_ops_list, ops); | |
282 | ||
2b499381 SR |
283 | if (ftrace_enabled) |
284 | update_ftrace_function(); | |
285 | ||
286 | return 0; | |
287 | } | |
288 | ||
289 | static int __unregister_ftrace_function(struct ftrace_ops *ops) | |
290 | { | |
291 | int ret; | |
292 | ||
293 | if (ftrace_disabled) | |
294 | return -ENODEV; | |
295 | ||
b848914c SR |
296 | if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) |
297 | return -EBUSY; | |
298 | ||
2b499381 SR |
299 | if (FTRACE_WARN_ON(ops == &global_ops)) |
300 | return -EINVAL; | |
301 | ||
b848914c SR |
302 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
303 | ret = remove_ftrace_ops(&ftrace_global_list, ops); | |
304 | if (!ret && ftrace_global_list == &ftrace_list_end) | |
305 | ret = remove_ftrace_ops(&ftrace_ops_list, &global_ops); | |
306 | if (!ret) | |
307 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; | |
308 | } else | |
309 | ret = remove_ftrace_ops(&ftrace_ops_list, ops); | |
310 | ||
2b499381 SR |
311 | if (ret < 0) |
312 | return ret; | |
b848914c | 313 | |
491d0dcf SR |
314 | if (ftrace_enabled) |
315 | update_ftrace_function(); | |
16444a8a | 316 | |
cdbe61bf SR |
317 | /* |
318 | * Dynamic ops may be freed, we must make sure that all | |
319 | * callers are done before leaving this function. | |
320 | */ | |
321 | if (ops->flags & FTRACE_OPS_FL_DYNAMIC) | |
322 | synchronize_sched(); | |
323 | ||
e6ea44e9 | 324 | return 0; |
3d083395 SR |
325 | } |
326 | ||
df4fc315 SR |
327 | static void ftrace_update_pid_func(void) |
328 | { | |
491d0dcf | 329 | /* Only do something if we are tracing something */ |
df4fc315 | 330 | if (ftrace_trace_function == ftrace_stub) |
10dd3ebe | 331 | return; |
df4fc315 | 332 | |
491d0dcf | 333 | update_ftrace_function(); |
df4fc315 SR |
334 | } |
335 | ||
493762fc SR |
336 | #ifdef CONFIG_FUNCTION_PROFILER |
337 | struct ftrace_profile { | |
338 | struct hlist_node node; | |
339 | unsigned long ip; | |
340 | unsigned long counter; | |
0706f1c4 SR |
341 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
342 | unsigned long long time; | |
e330b3bc | 343 | unsigned long long time_squared; |
0706f1c4 | 344 | #endif |
8fc0c701 SR |
345 | }; |
346 | ||
493762fc SR |
347 | struct ftrace_profile_page { |
348 | struct ftrace_profile_page *next; | |
349 | unsigned long index; | |
350 | struct ftrace_profile records[]; | |
d61f82d0 SR |
351 | }; |
352 | ||
cafb168a SR |
353 | struct ftrace_profile_stat { |
354 | atomic_t disabled; | |
355 | struct hlist_head *hash; | |
356 | struct ftrace_profile_page *pages; | |
357 | struct ftrace_profile_page *start; | |
358 | struct tracer_stat stat; | |
359 | }; | |
360 | ||
493762fc SR |
361 | #define PROFILE_RECORDS_SIZE \ |
362 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | |
5072c59f | 363 | |
493762fc SR |
364 | #define PROFILES_PER_PAGE \ |
365 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | |
3d083395 | 366 | |
fb9fb015 SR |
367 | static int ftrace_profile_bits __read_mostly; |
368 | static int ftrace_profile_enabled __read_mostly; | |
369 | ||
370 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ | |
bac429f0 SR |
371 | static DEFINE_MUTEX(ftrace_profile_lock); |
372 | ||
cafb168a | 373 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); |
493762fc SR |
374 | |
375 | #define FTRACE_PROFILE_HASH_SIZE 1024 /* must be power of 2 */ | |
376 | ||
bac429f0 SR |
377 | static void * |
378 | function_stat_next(void *v, int idx) | |
379 | { | |
493762fc SR |
380 | struct ftrace_profile *rec = v; |
381 | struct ftrace_profile_page *pg; | |
bac429f0 | 382 | |
493762fc | 383 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
bac429f0 SR |
384 | |
385 | again: | |
0296e425 LZ |
386 | if (idx != 0) |
387 | rec++; | |
388 | ||
bac429f0 SR |
389 | if ((void *)rec >= (void *)&pg->records[pg->index]) { |
390 | pg = pg->next; | |
391 | if (!pg) | |
392 | return NULL; | |
393 | rec = &pg->records[0]; | |
493762fc SR |
394 | if (!rec->counter) |
395 | goto again; | |
bac429f0 SR |
396 | } |
397 | ||
bac429f0 SR |
398 | return rec; |
399 | } | |
400 | ||
401 | static void *function_stat_start(struct tracer_stat *trace) | |
402 | { | |
cafb168a SR |
403 | struct ftrace_profile_stat *stat = |
404 | container_of(trace, struct ftrace_profile_stat, stat); | |
405 | ||
406 | if (!stat || !stat->start) | |
407 | return NULL; | |
408 | ||
409 | return function_stat_next(&stat->start->records[0], 0); | |
bac429f0 SR |
410 | } |
411 | ||
0706f1c4 SR |
412 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
413 | /* function graph compares on total time */ | |
414 | static int function_stat_cmp(void *p1, void *p2) | |
415 | { | |
416 | struct ftrace_profile *a = p1; | |
417 | struct ftrace_profile *b = p2; | |
418 | ||
419 | if (a->time < b->time) | |
420 | return -1; | |
421 | if (a->time > b->time) | |
422 | return 1; | |
423 | else | |
424 | return 0; | |
425 | } | |
426 | #else | |
427 | /* not function graph compares against hits */ | |
bac429f0 SR |
428 | static int function_stat_cmp(void *p1, void *p2) |
429 | { | |
493762fc SR |
430 | struct ftrace_profile *a = p1; |
431 | struct ftrace_profile *b = p2; | |
bac429f0 SR |
432 | |
433 | if (a->counter < b->counter) | |
434 | return -1; | |
435 | if (a->counter > b->counter) | |
436 | return 1; | |
437 | else | |
438 | return 0; | |
439 | } | |
0706f1c4 | 440 | #endif |
bac429f0 SR |
441 | |
442 | static int function_stat_headers(struct seq_file *m) | |
443 | { | |
0706f1c4 | 444 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b | 445 | seq_printf(m, " Function " |
e330b3bc | 446 | "Hit Time Avg s^2\n" |
34886c8b | 447 | " -------- " |
e330b3bc | 448 | "--- ---- --- ---\n"); |
0706f1c4 | 449 | #else |
bac429f0 SR |
450 | seq_printf(m, " Function Hit\n" |
451 | " -------- ---\n"); | |
0706f1c4 | 452 | #endif |
bac429f0 SR |
453 | return 0; |
454 | } | |
455 | ||
456 | static int function_stat_show(struct seq_file *m, void *v) | |
457 | { | |
493762fc | 458 | struct ftrace_profile *rec = v; |
bac429f0 | 459 | char str[KSYM_SYMBOL_LEN]; |
3aaba20f | 460 | int ret = 0; |
0706f1c4 | 461 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b SR |
462 | static struct trace_seq s; |
463 | unsigned long long avg; | |
e330b3bc | 464 | unsigned long long stddev; |
0706f1c4 | 465 | #endif |
3aaba20f LZ |
466 | mutex_lock(&ftrace_profile_lock); |
467 | ||
468 | /* we raced with function_profile_reset() */ | |
469 | if (unlikely(rec->counter == 0)) { | |
470 | ret = -EBUSY; | |
471 | goto out; | |
472 | } | |
bac429f0 SR |
473 | |
474 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
0706f1c4 SR |
475 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); |
476 | ||
477 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
478 | seq_printf(m, " "); | |
34886c8b SR |
479 | avg = rec->time; |
480 | do_div(avg, rec->counter); | |
481 | ||
e330b3bc CD |
482 | /* Sample standard deviation (s^2) */ |
483 | if (rec->counter <= 1) | |
484 | stddev = 0; | |
485 | else { | |
486 | stddev = rec->time_squared - rec->counter * avg * avg; | |
487 | /* | |
488 | * Divide only 1000 for ns^2 -> us^2 conversion. | |
489 | * trace_print_graph_duration will divide 1000 again. | |
490 | */ | |
491 | do_div(stddev, (rec->counter - 1) * 1000); | |
492 | } | |
493 | ||
34886c8b SR |
494 | trace_seq_init(&s); |
495 | trace_print_graph_duration(rec->time, &s); | |
496 | trace_seq_puts(&s, " "); | |
497 | trace_print_graph_duration(avg, &s); | |
e330b3bc CD |
498 | trace_seq_puts(&s, " "); |
499 | trace_print_graph_duration(stddev, &s); | |
0706f1c4 | 500 | trace_print_seq(m, &s); |
0706f1c4 SR |
501 | #endif |
502 | seq_putc(m, '\n'); | |
3aaba20f LZ |
503 | out: |
504 | mutex_unlock(&ftrace_profile_lock); | |
bac429f0 | 505 | |
3aaba20f | 506 | return ret; |
bac429f0 SR |
507 | } |
508 | ||
cafb168a | 509 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) |
bac429f0 | 510 | { |
493762fc | 511 | struct ftrace_profile_page *pg; |
bac429f0 | 512 | |
cafb168a | 513 | pg = stat->pages = stat->start; |
bac429f0 | 514 | |
493762fc SR |
515 | while (pg) { |
516 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | |
517 | pg->index = 0; | |
518 | pg = pg->next; | |
bac429f0 SR |
519 | } |
520 | ||
cafb168a | 521 | memset(stat->hash, 0, |
493762fc SR |
522 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); |
523 | } | |
bac429f0 | 524 | |
cafb168a | 525 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) |
493762fc SR |
526 | { |
527 | struct ftrace_profile_page *pg; | |
318e0a73 SR |
528 | int functions; |
529 | int pages; | |
493762fc | 530 | int i; |
bac429f0 | 531 | |
493762fc | 532 | /* If we already allocated, do nothing */ |
cafb168a | 533 | if (stat->pages) |
493762fc | 534 | return 0; |
bac429f0 | 535 | |
cafb168a SR |
536 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); |
537 | if (!stat->pages) | |
493762fc | 538 | return -ENOMEM; |
bac429f0 | 539 | |
318e0a73 SR |
540 | #ifdef CONFIG_DYNAMIC_FTRACE |
541 | functions = ftrace_update_tot_cnt; | |
542 | #else | |
543 | /* | |
544 | * We do not know the number of functions that exist because | |
545 | * dynamic tracing is what counts them. With past experience | |
546 | * we have around 20K functions. That should be more than enough. | |
547 | * It is highly unlikely we will execute every function in | |
548 | * the kernel. | |
549 | */ | |
550 | functions = 20000; | |
551 | #endif | |
552 | ||
cafb168a | 553 | pg = stat->start = stat->pages; |
bac429f0 | 554 | |
318e0a73 SR |
555 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); |
556 | ||
557 | for (i = 0; i < pages; i++) { | |
493762fc | 558 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
493762fc | 559 | if (!pg->next) |
318e0a73 | 560 | goto out_free; |
493762fc SR |
561 | pg = pg->next; |
562 | } | |
563 | ||
564 | return 0; | |
318e0a73 SR |
565 | |
566 | out_free: | |
567 | pg = stat->start; | |
568 | while (pg) { | |
569 | unsigned long tmp = (unsigned long)pg; | |
570 | ||
571 | pg = pg->next; | |
572 | free_page(tmp); | |
573 | } | |
574 | ||
575 | free_page((unsigned long)stat->pages); | |
576 | stat->pages = NULL; | |
577 | stat->start = NULL; | |
578 | ||
579 | return -ENOMEM; | |
bac429f0 SR |
580 | } |
581 | ||
cafb168a | 582 | static int ftrace_profile_init_cpu(int cpu) |
bac429f0 | 583 | { |
cafb168a | 584 | struct ftrace_profile_stat *stat; |
493762fc | 585 | int size; |
bac429f0 | 586 | |
cafb168a SR |
587 | stat = &per_cpu(ftrace_profile_stats, cpu); |
588 | ||
589 | if (stat->hash) { | |
493762fc | 590 | /* If the profile is already created, simply reset it */ |
cafb168a | 591 | ftrace_profile_reset(stat); |
493762fc SR |
592 | return 0; |
593 | } | |
bac429f0 | 594 | |
493762fc SR |
595 | /* |
596 | * We are profiling all functions, but usually only a few thousand | |
597 | * functions are hit. We'll make a hash of 1024 items. | |
598 | */ | |
599 | size = FTRACE_PROFILE_HASH_SIZE; | |
bac429f0 | 600 | |
cafb168a | 601 | stat->hash = kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL); |
493762fc | 602 | |
cafb168a | 603 | if (!stat->hash) |
493762fc SR |
604 | return -ENOMEM; |
605 | ||
cafb168a SR |
606 | if (!ftrace_profile_bits) { |
607 | size--; | |
493762fc | 608 | |
cafb168a SR |
609 | for (; size; size >>= 1) |
610 | ftrace_profile_bits++; | |
611 | } | |
493762fc | 612 | |
318e0a73 | 613 | /* Preallocate the function profiling pages */ |
cafb168a SR |
614 | if (ftrace_profile_pages_init(stat) < 0) { |
615 | kfree(stat->hash); | |
616 | stat->hash = NULL; | |
493762fc SR |
617 | return -ENOMEM; |
618 | } | |
619 | ||
620 | return 0; | |
bac429f0 SR |
621 | } |
622 | ||
cafb168a SR |
623 | static int ftrace_profile_init(void) |
624 | { | |
625 | int cpu; | |
626 | int ret = 0; | |
627 | ||
628 | for_each_online_cpu(cpu) { | |
629 | ret = ftrace_profile_init_cpu(cpu); | |
630 | if (ret) | |
631 | break; | |
632 | } | |
633 | ||
634 | return ret; | |
635 | } | |
636 | ||
493762fc | 637 | /* interrupts must be disabled */ |
cafb168a SR |
638 | static struct ftrace_profile * |
639 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) | |
bac429f0 | 640 | { |
493762fc | 641 | struct ftrace_profile *rec; |
bac429f0 SR |
642 | struct hlist_head *hhd; |
643 | struct hlist_node *n; | |
bac429f0 SR |
644 | unsigned long key; |
645 | ||
bac429f0 | 646 | key = hash_long(ip, ftrace_profile_bits); |
cafb168a | 647 | hhd = &stat->hash[key]; |
bac429f0 SR |
648 | |
649 | if (hlist_empty(hhd)) | |
650 | return NULL; | |
651 | ||
bac429f0 SR |
652 | hlist_for_each_entry_rcu(rec, n, hhd, node) { |
653 | if (rec->ip == ip) | |
493762fc SR |
654 | return rec; |
655 | } | |
656 | ||
657 | return NULL; | |
658 | } | |
659 | ||
cafb168a SR |
660 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, |
661 | struct ftrace_profile *rec) | |
493762fc SR |
662 | { |
663 | unsigned long key; | |
664 | ||
665 | key = hash_long(rec->ip, ftrace_profile_bits); | |
cafb168a | 666 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); |
493762fc SR |
667 | } |
668 | ||
318e0a73 SR |
669 | /* |
670 | * The memory is already allocated, this simply finds a new record to use. | |
671 | */ | |
493762fc | 672 | static struct ftrace_profile * |
318e0a73 | 673 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) |
493762fc SR |
674 | { |
675 | struct ftrace_profile *rec = NULL; | |
676 | ||
318e0a73 | 677 | /* prevent recursion (from NMIs) */ |
cafb168a | 678 | if (atomic_inc_return(&stat->disabled) != 1) |
493762fc SR |
679 | goto out; |
680 | ||
493762fc | 681 | /* |
318e0a73 SR |
682 | * Try to find the function again since an NMI |
683 | * could have added it | |
493762fc | 684 | */ |
cafb168a | 685 | rec = ftrace_find_profiled_func(stat, ip); |
493762fc | 686 | if (rec) |
cafb168a | 687 | goto out; |
493762fc | 688 | |
cafb168a SR |
689 | if (stat->pages->index == PROFILES_PER_PAGE) { |
690 | if (!stat->pages->next) | |
691 | goto out; | |
692 | stat->pages = stat->pages->next; | |
bac429f0 | 693 | } |
493762fc | 694 | |
cafb168a | 695 | rec = &stat->pages->records[stat->pages->index++]; |
493762fc | 696 | rec->ip = ip; |
cafb168a | 697 | ftrace_add_profile(stat, rec); |
493762fc | 698 | |
bac429f0 | 699 | out: |
cafb168a | 700 | atomic_dec(&stat->disabled); |
bac429f0 SR |
701 | |
702 | return rec; | |
703 | } | |
704 | ||
705 | static void | |
706 | function_profile_call(unsigned long ip, unsigned long parent_ip) | |
707 | { | |
cafb168a | 708 | struct ftrace_profile_stat *stat; |
493762fc | 709 | struct ftrace_profile *rec; |
bac429f0 SR |
710 | unsigned long flags; |
711 | ||
712 | if (!ftrace_profile_enabled) | |
713 | return; | |
714 | ||
715 | local_irq_save(flags); | |
cafb168a SR |
716 | |
717 | stat = &__get_cpu_var(ftrace_profile_stats); | |
0f6ce3de | 718 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
719 | goto out; |
720 | ||
721 | rec = ftrace_find_profiled_func(stat, ip); | |
493762fc | 722 | if (!rec) { |
318e0a73 | 723 | rec = ftrace_profile_alloc(stat, ip); |
493762fc SR |
724 | if (!rec) |
725 | goto out; | |
726 | } | |
bac429f0 SR |
727 | |
728 | rec->counter++; | |
729 | out: | |
730 | local_irq_restore(flags); | |
731 | } | |
732 | ||
0706f1c4 SR |
733 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
734 | static int profile_graph_entry(struct ftrace_graph_ent *trace) | |
735 | { | |
736 | function_profile_call(trace->func, 0); | |
737 | return 1; | |
738 | } | |
739 | ||
740 | static void profile_graph_return(struct ftrace_graph_ret *trace) | |
741 | { | |
cafb168a | 742 | struct ftrace_profile_stat *stat; |
a2a16d6a | 743 | unsigned long long calltime; |
0706f1c4 | 744 | struct ftrace_profile *rec; |
cafb168a | 745 | unsigned long flags; |
0706f1c4 SR |
746 | |
747 | local_irq_save(flags); | |
cafb168a | 748 | stat = &__get_cpu_var(ftrace_profile_stats); |
0f6ce3de | 749 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
750 | goto out; |
751 | ||
37e44bc5 SR |
752 | /* If the calltime was zero'd ignore it */ |
753 | if (!trace->calltime) | |
754 | goto out; | |
755 | ||
a2a16d6a SR |
756 | calltime = trace->rettime - trace->calltime; |
757 | ||
758 | if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) { | |
759 | int index; | |
760 | ||
761 | index = trace->depth; | |
762 | ||
763 | /* Append this call time to the parent time to subtract */ | |
764 | if (index) | |
765 | current->ret_stack[index - 1].subtime += calltime; | |
766 | ||
767 | if (current->ret_stack[index].subtime < calltime) | |
768 | calltime -= current->ret_stack[index].subtime; | |
769 | else | |
770 | calltime = 0; | |
771 | } | |
772 | ||
cafb168a | 773 | rec = ftrace_find_profiled_func(stat, trace->func); |
e330b3bc | 774 | if (rec) { |
a2a16d6a | 775 | rec->time += calltime; |
e330b3bc CD |
776 | rec->time_squared += calltime * calltime; |
777 | } | |
a2a16d6a | 778 | |
cafb168a | 779 | out: |
0706f1c4 SR |
780 | local_irq_restore(flags); |
781 | } | |
782 | ||
783 | static int register_ftrace_profiler(void) | |
784 | { | |
785 | return register_ftrace_graph(&profile_graph_return, | |
786 | &profile_graph_entry); | |
787 | } | |
788 | ||
789 | static void unregister_ftrace_profiler(void) | |
790 | { | |
791 | unregister_ftrace_graph(); | |
792 | } | |
793 | #else | |
bd38c0e6 | 794 | static struct ftrace_ops ftrace_profile_ops __read_mostly = { |
fb9fb015 | 795 | .func = function_profile_call, |
bac429f0 SR |
796 | }; |
797 | ||
0706f1c4 SR |
798 | static int register_ftrace_profiler(void) |
799 | { | |
800 | return register_ftrace_function(&ftrace_profile_ops); | |
801 | } | |
802 | ||
803 | static void unregister_ftrace_profiler(void) | |
804 | { | |
805 | unregister_ftrace_function(&ftrace_profile_ops); | |
806 | } | |
807 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
808 | ||
bac429f0 SR |
809 | static ssize_t |
810 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | |
811 | size_t cnt, loff_t *ppos) | |
812 | { | |
813 | unsigned long val; | |
bac429f0 SR |
814 | int ret; |
815 | ||
22fe9b54 PH |
816 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
817 | if (ret) | |
bac429f0 SR |
818 | return ret; |
819 | ||
820 | val = !!val; | |
821 | ||
822 | mutex_lock(&ftrace_profile_lock); | |
823 | if (ftrace_profile_enabled ^ val) { | |
824 | if (val) { | |
493762fc SR |
825 | ret = ftrace_profile_init(); |
826 | if (ret < 0) { | |
827 | cnt = ret; | |
828 | goto out; | |
829 | } | |
830 | ||
0706f1c4 SR |
831 | ret = register_ftrace_profiler(); |
832 | if (ret < 0) { | |
833 | cnt = ret; | |
834 | goto out; | |
835 | } | |
bac429f0 SR |
836 | ftrace_profile_enabled = 1; |
837 | } else { | |
838 | ftrace_profile_enabled = 0; | |
0f6ce3de SR |
839 | /* |
840 | * unregister_ftrace_profiler calls stop_machine | |
841 | * so this acts like an synchronize_sched. | |
842 | */ | |
0706f1c4 | 843 | unregister_ftrace_profiler(); |
bac429f0 SR |
844 | } |
845 | } | |
493762fc | 846 | out: |
bac429f0 SR |
847 | mutex_unlock(&ftrace_profile_lock); |
848 | ||
cf8517cf | 849 | *ppos += cnt; |
bac429f0 SR |
850 | |
851 | return cnt; | |
852 | } | |
853 | ||
493762fc SR |
854 | static ssize_t |
855 | ftrace_profile_read(struct file *filp, char __user *ubuf, | |
856 | size_t cnt, loff_t *ppos) | |
857 | { | |
fb9fb015 | 858 | char buf[64]; /* big enough to hold a number */ |
493762fc SR |
859 | int r; |
860 | ||
861 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | |
862 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
863 | } | |
864 | ||
bac429f0 SR |
865 | static const struct file_operations ftrace_profile_fops = { |
866 | .open = tracing_open_generic, | |
867 | .read = ftrace_profile_read, | |
868 | .write = ftrace_profile_write, | |
6038f373 | 869 | .llseek = default_llseek, |
bac429f0 SR |
870 | }; |
871 | ||
cafb168a SR |
872 | /* used to initialize the real stat files */ |
873 | static struct tracer_stat function_stats __initdata = { | |
fb9fb015 SR |
874 | .name = "functions", |
875 | .stat_start = function_stat_start, | |
876 | .stat_next = function_stat_next, | |
877 | .stat_cmp = function_stat_cmp, | |
878 | .stat_headers = function_stat_headers, | |
879 | .stat_show = function_stat_show | |
cafb168a SR |
880 | }; |
881 | ||
6ab5d668 | 882 | static __init void ftrace_profile_debugfs(struct dentry *d_tracer) |
bac429f0 | 883 | { |
cafb168a | 884 | struct ftrace_profile_stat *stat; |
bac429f0 | 885 | struct dentry *entry; |
cafb168a | 886 | char *name; |
bac429f0 | 887 | int ret; |
cafb168a SR |
888 | int cpu; |
889 | ||
890 | for_each_possible_cpu(cpu) { | |
891 | stat = &per_cpu(ftrace_profile_stats, cpu); | |
892 | ||
893 | /* allocate enough for function name + cpu number */ | |
894 | name = kmalloc(32, GFP_KERNEL); | |
895 | if (!name) { | |
896 | /* | |
897 | * The files created are permanent, if something happens | |
898 | * we still do not free memory. | |
899 | */ | |
cafb168a SR |
900 | WARN(1, |
901 | "Could not allocate stat file for cpu %d\n", | |
902 | cpu); | |
903 | return; | |
904 | } | |
905 | stat->stat = function_stats; | |
906 | snprintf(name, 32, "function%d", cpu); | |
907 | stat->stat.name = name; | |
908 | ret = register_stat_tracer(&stat->stat); | |
909 | if (ret) { | |
910 | WARN(1, | |
911 | "Could not register function stat for cpu %d\n", | |
912 | cpu); | |
913 | kfree(name); | |
914 | return; | |
915 | } | |
bac429f0 SR |
916 | } |
917 | ||
918 | entry = debugfs_create_file("function_profile_enabled", 0644, | |
919 | d_tracer, NULL, &ftrace_profile_fops); | |
920 | if (!entry) | |
921 | pr_warning("Could not create debugfs " | |
922 | "'function_profile_enabled' entry\n"); | |
923 | } | |
924 | ||
bac429f0 | 925 | #else /* CONFIG_FUNCTION_PROFILER */ |
6ab5d668 | 926 | static __init void ftrace_profile_debugfs(struct dentry *d_tracer) |
bac429f0 SR |
927 | { |
928 | } | |
bac429f0 SR |
929 | #endif /* CONFIG_FUNCTION_PROFILER */ |
930 | ||
493762fc SR |
931 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; |
932 | ||
933 | #ifdef CONFIG_DYNAMIC_FTRACE | |
934 | ||
935 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD | |
936 | # error Dynamic ftrace depends on MCOUNT_RECORD | |
937 | #endif | |
938 | ||
939 | static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly; | |
940 | ||
941 | struct ftrace_func_probe { | |
942 | struct hlist_node node; | |
943 | struct ftrace_probe_ops *ops; | |
944 | unsigned long flags; | |
945 | unsigned long ip; | |
946 | void *data; | |
947 | struct rcu_head rcu; | |
948 | }; | |
949 | ||
950 | enum { | |
951 | FTRACE_ENABLE_CALLS = (1 << 0), | |
952 | FTRACE_DISABLE_CALLS = (1 << 1), | |
953 | FTRACE_UPDATE_TRACE_FUNC = (1 << 2), | |
79e406d7 SR |
954 | FTRACE_START_FUNC_RET = (1 << 3), |
955 | FTRACE_STOP_FUNC_RET = (1 << 4), | |
493762fc | 956 | }; |
b448c4e3 SR |
957 | struct ftrace_func_entry { |
958 | struct hlist_node hlist; | |
959 | unsigned long ip; | |
960 | }; | |
961 | ||
962 | struct ftrace_hash { | |
963 | unsigned long size_bits; | |
964 | struct hlist_head *buckets; | |
965 | unsigned long count; | |
07fd5515 | 966 | struct rcu_head rcu; |
b448c4e3 SR |
967 | }; |
968 | ||
33dc9b12 SR |
969 | /* |
970 | * We make these constant because no one should touch them, | |
971 | * but they are used as the default "empty hash", to avoid allocating | |
972 | * it all the time. These are in a read only section such that if | |
973 | * anyone does try to modify it, it will cause an exception. | |
974 | */ | |
975 | static const struct hlist_head empty_buckets[1]; | |
976 | static const struct ftrace_hash empty_hash = { | |
977 | .buckets = (struct hlist_head *)empty_buckets, | |
1cf41dd7 | 978 | }; |
33dc9b12 | 979 | #define EMPTY_HASH ((struct ftrace_hash *)&empty_hash) |
493762fc | 980 | |
2b499381 | 981 | static struct ftrace_ops global_ops = { |
f45948e8 | 982 | .func = ftrace_stub, |
33dc9b12 SR |
983 | .notrace_hash = EMPTY_HASH, |
984 | .filter_hash = EMPTY_HASH, | |
f45948e8 SR |
985 | }; |
986 | ||
493762fc SR |
987 | static struct dyn_ftrace *ftrace_new_addrs; |
988 | ||
989 | static DEFINE_MUTEX(ftrace_regex_lock); | |
990 | ||
991 | struct ftrace_page { | |
992 | struct ftrace_page *next; | |
993 | int index; | |
994 | struct dyn_ftrace records[]; | |
995 | }; | |
996 | ||
997 | #define ENTRIES_PER_PAGE \ | |
998 | ((PAGE_SIZE - sizeof(struct ftrace_page)) / sizeof(struct dyn_ftrace)) | |
999 | ||
1000 | /* estimate from running different kernels */ | |
1001 | #define NR_TO_INIT 10000 | |
1002 | ||
1003 | static struct ftrace_page *ftrace_pages_start; | |
1004 | static struct ftrace_page *ftrace_pages; | |
1005 | ||
1006 | static struct dyn_ftrace *ftrace_free_records; | |
1007 | ||
b448c4e3 SR |
1008 | static struct ftrace_func_entry * |
1009 | ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
1010 | { | |
1011 | unsigned long key; | |
1012 | struct ftrace_func_entry *entry; | |
1013 | struct hlist_head *hhd; | |
1014 | struct hlist_node *n; | |
1015 | ||
1016 | if (!hash->count) | |
1017 | return NULL; | |
1018 | ||
1019 | if (hash->size_bits > 0) | |
1020 | key = hash_long(ip, hash->size_bits); | |
1021 | else | |
1022 | key = 0; | |
1023 | ||
1024 | hhd = &hash->buckets[key]; | |
1025 | ||
1026 | hlist_for_each_entry_rcu(entry, n, hhd, hlist) { | |
1027 | if (entry->ip == ip) | |
1028 | return entry; | |
1029 | } | |
1030 | return NULL; | |
1031 | } | |
1032 | ||
33dc9b12 SR |
1033 | static void __add_hash_entry(struct ftrace_hash *hash, |
1034 | struct ftrace_func_entry *entry) | |
b448c4e3 | 1035 | { |
b448c4e3 SR |
1036 | struct hlist_head *hhd; |
1037 | unsigned long key; | |
1038 | ||
b448c4e3 | 1039 | if (hash->size_bits) |
33dc9b12 | 1040 | key = hash_long(entry->ip, hash->size_bits); |
b448c4e3 SR |
1041 | else |
1042 | key = 0; | |
1043 | ||
b448c4e3 SR |
1044 | hhd = &hash->buckets[key]; |
1045 | hlist_add_head(&entry->hlist, hhd); | |
1046 | hash->count++; | |
33dc9b12 SR |
1047 | } |
1048 | ||
1049 | static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) | |
1050 | { | |
1051 | struct ftrace_func_entry *entry; | |
1052 | ||
1053 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
1054 | if (!entry) | |
1055 | return -ENOMEM; | |
1056 | ||
1057 | entry->ip = ip; | |
1058 | __add_hash_entry(hash, entry); | |
b448c4e3 SR |
1059 | |
1060 | return 0; | |
1061 | } | |
1062 | ||
1063 | static void | |
33dc9b12 | 1064 | free_hash_entry(struct ftrace_hash *hash, |
b448c4e3 SR |
1065 | struct ftrace_func_entry *entry) |
1066 | { | |
1067 | hlist_del(&entry->hlist); | |
1068 | kfree(entry); | |
1069 | hash->count--; | |
1070 | } | |
1071 | ||
33dc9b12 SR |
1072 | static void |
1073 | remove_hash_entry(struct ftrace_hash *hash, | |
1074 | struct ftrace_func_entry *entry) | |
1075 | { | |
1076 | hlist_del(&entry->hlist); | |
1077 | hash->count--; | |
1078 | } | |
1079 | ||
b448c4e3 SR |
1080 | static void ftrace_hash_clear(struct ftrace_hash *hash) |
1081 | { | |
1082 | struct hlist_head *hhd; | |
1083 | struct hlist_node *tp, *tn; | |
1084 | struct ftrace_func_entry *entry; | |
1085 | int size = 1 << hash->size_bits; | |
1086 | int i; | |
1087 | ||
33dc9b12 SR |
1088 | if (!hash->count) |
1089 | return; | |
1090 | ||
b448c4e3 SR |
1091 | for (i = 0; i < size; i++) { |
1092 | hhd = &hash->buckets[i]; | |
1093 | hlist_for_each_entry_safe(entry, tp, tn, hhd, hlist) | |
33dc9b12 | 1094 | free_hash_entry(hash, entry); |
b448c4e3 SR |
1095 | } |
1096 | FTRACE_WARN_ON(hash->count); | |
1097 | } | |
1098 | ||
33dc9b12 SR |
1099 | static void free_ftrace_hash(struct ftrace_hash *hash) |
1100 | { | |
1101 | if (!hash || hash == EMPTY_HASH) | |
1102 | return; | |
1103 | ftrace_hash_clear(hash); | |
1104 | kfree(hash->buckets); | |
1105 | kfree(hash); | |
1106 | } | |
1107 | ||
07fd5515 SR |
1108 | static void __free_ftrace_hash_rcu(struct rcu_head *rcu) |
1109 | { | |
1110 | struct ftrace_hash *hash; | |
1111 | ||
1112 | hash = container_of(rcu, struct ftrace_hash, rcu); | |
1113 | free_ftrace_hash(hash); | |
1114 | } | |
1115 | ||
1116 | static void free_ftrace_hash_rcu(struct ftrace_hash *hash) | |
1117 | { | |
1118 | if (!hash || hash == EMPTY_HASH) | |
1119 | return; | |
1120 | call_rcu_sched(&hash->rcu, __free_ftrace_hash_rcu); | |
1121 | } | |
1122 | ||
33dc9b12 SR |
1123 | static struct ftrace_hash *alloc_ftrace_hash(int size_bits) |
1124 | { | |
1125 | struct ftrace_hash *hash; | |
1126 | int size; | |
1127 | ||
1128 | hash = kzalloc(sizeof(*hash), GFP_KERNEL); | |
1129 | if (!hash) | |
1130 | return NULL; | |
1131 | ||
1132 | size = 1 << size_bits; | |
1133 | hash->buckets = kzalloc(sizeof(*hash->buckets) * size, GFP_KERNEL); | |
1134 | ||
1135 | if (!hash->buckets) { | |
1136 | kfree(hash); | |
1137 | return NULL; | |
1138 | } | |
1139 | ||
1140 | hash->size_bits = size_bits; | |
1141 | ||
1142 | return hash; | |
1143 | } | |
1144 | ||
1145 | static struct ftrace_hash * | |
1146 | alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) | |
1147 | { | |
1148 | struct ftrace_func_entry *entry; | |
1149 | struct ftrace_hash *new_hash; | |
1150 | struct hlist_node *tp; | |
1151 | int size; | |
1152 | int ret; | |
1153 | int i; | |
1154 | ||
1155 | new_hash = alloc_ftrace_hash(size_bits); | |
1156 | if (!new_hash) | |
1157 | return NULL; | |
1158 | ||
1159 | /* Empty hash? */ | |
1160 | if (!hash || !hash->count) | |
1161 | return new_hash; | |
1162 | ||
1163 | size = 1 << hash->size_bits; | |
1164 | for (i = 0; i < size; i++) { | |
1165 | hlist_for_each_entry(entry, tp, &hash->buckets[i], hlist) { | |
1166 | ret = add_hash_entry(new_hash, entry->ip); | |
1167 | if (ret < 0) | |
1168 | goto free_hash; | |
1169 | } | |
1170 | } | |
1171 | ||
1172 | FTRACE_WARN_ON(new_hash->count != hash->count); | |
1173 | ||
1174 | return new_hash; | |
1175 | ||
1176 | free_hash: | |
1177 | free_ftrace_hash(new_hash); | |
1178 | return NULL; | |
1179 | } | |
1180 | ||
41fb61c2 SR |
1181 | static void |
1182 | ftrace_hash_rec_disable(struct ftrace_ops *ops, int filter_hash); | |
1183 | static void | |
1184 | ftrace_hash_rec_enable(struct ftrace_ops *ops, int filter_hash); | |
1185 | ||
33dc9b12 | 1186 | static int |
41fb61c2 SR |
1187 | ftrace_hash_move(struct ftrace_ops *ops, int enable, |
1188 | struct ftrace_hash **dst, struct ftrace_hash *src) | |
33dc9b12 SR |
1189 | { |
1190 | struct ftrace_func_entry *entry; | |
1191 | struct hlist_node *tp, *tn; | |
1192 | struct hlist_head *hhd; | |
07fd5515 SR |
1193 | struct ftrace_hash *old_hash; |
1194 | struct ftrace_hash *new_hash; | |
33dc9b12 SR |
1195 | unsigned long key; |
1196 | int size = src->count; | |
1197 | int bits = 0; | |
41fb61c2 | 1198 | int ret; |
33dc9b12 SR |
1199 | int i; |
1200 | ||
41fb61c2 SR |
1201 | /* |
1202 | * Remove the current set, update the hash and add | |
1203 | * them back. | |
1204 | */ | |
1205 | ftrace_hash_rec_disable(ops, enable); | |
1206 | ||
33dc9b12 SR |
1207 | /* |
1208 | * If the new source is empty, just free dst and assign it | |
1209 | * the empty_hash. | |
1210 | */ | |
1211 | if (!src->count) { | |
07fd5515 SR |
1212 | free_ftrace_hash_rcu(*dst); |
1213 | rcu_assign_pointer(*dst, EMPTY_HASH); | |
d4d34b98 SR |
1214 | /* still need to update the function records */ |
1215 | ret = 0; | |
1216 | goto out; | |
33dc9b12 SR |
1217 | } |
1218 | ||
33dc9b12 SR |
1219 | /* |
1220 | * Make the hash size about 1/2 the # found | |
1221 | */ | |
1222 | for (size /= 2; size; size >>= 1) | |
1223 | bits++; | |
1224 | ||
1225 | /* Don't allocate too much */ | |
1226 | if (bits > FTRACE_HASH_MAX_BITS) | |
1227 | bits = FTRACE_HASH_MAX_BITS; | |
1228 | ||
41fb61c2 | 1229 | ret = -ENOMEM; |
07fd5515 SR |
1230 | new_hash = alloc_ftrace_hash(bits); |
1231 | if (!new_hash) | |
41fb61c2 | 1232 | goto out; |
33dc9b12 SR |
1233 | |
1234 | size = 1 << src->size_bits; | |
1235 | for (i = 0; i < size; i++) { | |
1236 | hhd = &src->buckets[i]; | |
1237 | hlist_for_each_entry_safe(entry, tp, tn, hhd, hlist) { | |
1238 | if (bits > 0) | |
1239 | key = hash_long(entry->ip, bits); | |
1240 | else | |
1241 | key = 0; | |
1242 | remove_hash_entry(src, entry); | |
07fd5515 | 1243 | __add_hash_entry(new_hash, entry); |
33dc9b12 SR |
1244 | } |
1245 | } | |
1246 | ||
07fd5515 SR |
1247 | old_hash = *dst; |
1248 | rcu_assign_pointer(*dst, new_hash); | |
1249 | free_ftrace_hash_rcu(old_hash); | |
1250 | ||
41fb61c2 SR |
1251 | ret = 0; |
1252 | out: | |
1253 | /* | |
1254 | * Enable regardless of ret: | |
1255 | * On success, we enable the new hash. | |
1256 | * On failure, we re-enable the original hash. | |
1257 | */ | |
1258 | ftrace_hash_rec_enable(ops, enable); | |
1259 | ||
1260 | return ret; | |
33dc9b12 SR |
1261 | } |
1262 | ||
b848914c SR |
1263 | /* |
1264 | * Test the hashes for this ops to see if we want to call | |
1265 | * the ops->func or not. | |
1266 | * | |
1267 | * It's a match if the ip is in the ops->filter_hash or | |
1268 | * the filter_hash does not exist or is empty, | |
1269 | * AND | |
1270 | * the ip is not in the ops->notrace_hash. | |
cdbe61bf SR |
1271 | * |
1272 | * This needs to be called with preemption disabled as | |
1273 | * the hashes are freed with call_rcu_sched(). | |
b848914c SR |
1274 | */ |
1275 | static int | |
1276 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip) | |
1277 | { | |
1278 | struct ftrace_hash *filter_hash; | |
1279 | struct ftrace_hash *notrace_hash; | |
1280 | int ret; | |
1281 | ||
b848914c SR |
1282 | filter_hash = rcu_dereference_raw(ops->filter_hash); |
1283 | notrace_hash = rcu_dereference_raw(ops->notrace_hash); | |
1284 | ||
1285 | if ((!filter_hash || !filter_hash->count || | |
1286 | ftrace_lookup_ip(filter_hash, ip)) && | |
1287 | (!notrace_hash || !notrace_hash->count || | |
1288 | !ftrace_lookup_ip(notrace_hash, ip))) | |
1289 | ret = 1; | |
1290 | else | |
1291 | ret = 0; | |
b848914c SR |
1292 | |
1293 | return ret; | |
1294 | } | |
1295 | ||
493762fc SR |
1296 | /* |
1297 | * This is a double for. Do not use 'break' to break out of the loop, | |
1298 | * you must use a goto. | |
1299 | */ | |
1300 | #define do_for_each_ftrace_rec(pg, rec) \ | |
1301 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
1302 | int _____i; \ | |
1303 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
1304 | rec = &pg->records[_____i]; | |
1305 | ||
1306 | #define while_for_each_ftrace_rec() \ | |
1307 | } \ | |
1308 | } | |
1309 | ||
ed926f9b SR |
1310 | static void __ftrace_hash_rec_update(struct ftrace_ops *ops, |
1311 | int filter_hash, | |
1312 | bool inc) | |
1313 | { | |
1314 | struct ftrace_hash *hash; | |
1315 | struct ftrace_hash *other_hash; | |
1316 | struct ftrace_page *pg; | |
1317 | struct dyn_ftrace *rec; | |
1318 | int count = 0; | |
1319 | int all = 0; | |
1320 | ||
1321 | /* Only update if the ops has been registered */ | |
1322 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
1323 | return; | |
1324 | ||
1325 | /* | |
1326 | * In the filter_hash case: | |
1327 | * If the count is zero, we update all records. | |
1328 | * Otherwise we just update the items in the hash. | |
1329 | * | |
1330 | * In the notrace_hash case: | |
1331 | * We enable the update in the hash. | |
1332 | * As disabling notrace means enabling the tracing, | |
1333 | * and enabling notrace means disabling, the inc variable | |
1334 | * gets inversed. | |
1335 | */ | |
1336 | if (filter_hash) { | |
1337 | hash = ops->filter_hash; | |
1338 | other_hash = ops->notrace_hash; | |
b848914c | 1339 | if (!hash || !hash->count) |
ed926f9b SR |
1340 | all = 1; |
1341 | } else { | |
1342 | inc = !inc; | |
1343 | hash = ops->notrace_hash; | |
1344 | other_hash = ops->filter_hash; | |
1345 | /* | |
1346 | * If the notrace hash has no items, | |
1347 | * then there's nothing to do. | |
1348 | */ | |
b848914c | 1349 | if (hash && !hash->count) |
ed926f9b SR |
1350 | return; |
1351 | } | |
1352 | ||
1353 | do_for_each_ftrace_rec(pg, rec) { | |
1354 | int in_other_hash = 0; | |
1355 | int in_hash = 0; | |
1356 | int match = 0; | |
1357 | ||
1358 | if (all) { | |
1359 | /* | |
1360 | * Only the filter_hash affects all records. | |
1361 | * Update if the record is not in the notrace hash. | |
1362 | */ | |
b848914c | 1363 | if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip)) |
ed926f9b SR |
1364 | match = 1; |
1365 | } else { | |
b848914c SR |
1366 | in_hash = hash && !!ftrace_lookup_ip(hash, rec->ip); |
1367 | in_other_hash = other_hash && !!ftrace_lookup_ip(other_hash, rec->ip); | |
ed926f9b SR |
1368 | |
1369 | /* | |
1370 | * | |
1371 | */ | |
1372 | if (filter_hash && in_hash && !in_other_hash) | |
1373 | match = 1; | |
1374 | else if (!filter_hash && in_hash && | |
1375 | (in_other_hash || !other_hash->count)) | |
1376 | match = 1; | |
1377 | } | |
1378 | if (!match) | |
1379 | continue; | |
1380 | ||
1381 | if (inc) { | |
1382 | rec->flags++; | |
1383 | if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == FTRACE_REF_MAX)) | |
1384 | return; | |
1385 | } else { | |
1386 | if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == 0)) | |
1387 | return; | |
1388 | rec->flags--; | |
1389 | } | |
1390 | count++; | |
1391 | /* Shortcut, if we handled all records, we are done. */ | |
1392 | if (!all && count == hash->count) | |
1393 | return; | |
1394 | } while_for_each_ftrace_rec(); | |
1395 | } | |
1396 | ||
1397 | static void ftrace_hash_rec_disable(struct ftrace_ops *ops, | |
1398 | int filter_hash) | |
1399 | { | |
1400 | __ftrace_hash_rec_update(ops, filter_hash, 0); | |
1401 | } | |
1402 | ||
1403 | static void ftrace_hash_rec_enable(struct ftrace_ops *ops, | |
1404 | int filter_hash) | |
1405 | { | |
1406 | __ftrace_hash_rec_update(ops, filter_hash, 1); | |
1407 | } | |
1408 | ||
e309b41d | 1409 | static void ftrace_free_rec(struct dyn_ftrace *rec) |
37ad5084 | 1410 | { |
ee000b7f | 1411 | rec->freelist = ftrace_free_records; |
37ad5084 SR |
1412 | ftrace_free_records = rec; |
1413 | rec->flags |= FTRACE_FL_FREE; | |
1414 | } | |
1415 | ||
e309b41d | 1416 | static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip) |
3c1720f0 | 1417 | { |
37ad5084 SR |
1418 | struct dyn_ftrace *rec; |
1419 | ||
1420 | /* First check for freed records */ | |
1421 | if (ftrace_free_records) { | |
1422 | rec = ftrace_free_records; | |
1423 | ||
37ad5084 | 1424 | if (unlikely(!(rec->flags & FTRACE_FL_FREE))) { |
6912896e | 1425 | FTRACE_WARN_ON_ONCE(1); |
37ad5084 SR |
1426 | ftrace_free_records = NULL; |
1427 | return NULL; | |
1428 | } | |
1429 | ||
ee000b7f | 1430 | ftrace_free_records = rec->freelist; |
37ad5084 SR |
1431 | memset(rec, 0, sizeof(*rec)); |
1432 | return rec; | |
1433 | } | |
1434 | ||
3c1720f0 | 1435 | if (ftrace_pages->index == ENTRIES_PER_PAGE) { |
08f5ac90 SR |
1436 | if (!ftrace_pages->next) { |
1437 | /* allocate another page */ | |
1438 | ftrace_pages->next = | |
1439 | (void *)get_zeroed_page(GFP_KERNEL); | |
1440 | if (!ftrace_pages->next) | |
1441 | return NULL; | |
1442 | } | |
3c1720f0 SR |
1443 | ftrace_pages = ftrace_pages->next; |
1444 | } | |
1445 | ||
1446 | return &ftrace_pages->records[ftrace_pages->index++]; | |
1447 | } | |
1448 | ||
08f5ac90 | 1449 | static struct dyn_ftrace * |
d61f82d0 | 1450 | ftrace_record_ip(unsigned long ip) |
3d083395 | 1451 | { |
08f5ac90 | 1452 | struct dyn_ftrace *rec; |
3d083395 | 1453 | |
f3c7ac40 | 1454 | if (ftrace_disabled) |
08f5ac90 | 1455 | return NULL; |
3d083395 | 1456 | |
08f5ac90 SR |
1457 | rec = ftrace_alloc_dyn_node(ip); |
1458 | if (!rec) | |
1459 | return NULL; | |
3d083395 | 1460 | |
08f5ac90 | 1461 | rec->ip = ip; |
ee000b7f | 1462 | rec->newlist = ftrace_new_addrs; |
e94142a6 | 1463 | ftrace_new_addrs = rec; |
3d083395 | 1464 | |
08f5ac90 | 1465 | return rec; |
3d083395 SR |
1466 | } |
1467 | ||
b17e8a37 SR |
1468 | static void print_ip_ins(const char *fmt, unsigned char *p) |
1469 | { | |
1470 | int i; | |
1471 | ||
1472 | printk(KERN_CONT "%s", fmt); | |
1473 | ||
1474 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
1475 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
1476 | } | |
1477 | ||
31e88909 | 1478 | static void ftrace_bug(int failed, unsigned long ip) |
b17e8a37 SR |
1479 | { |
1480 | switch (failed) { | |
1481 | case -EFAULT: | |
1482 | FTRACE_WARN_ON_ONCE(1); | |
1483 | pr_info("ftrace faulted on modifying "); | |
1484 | print_ip_sym(ip); | |
1485 | break; | |
1486 | case -EINVAL: | |
1487 | FTRACE_WARN_ON_ONCE(1); | |
1488 | pr_info("ftrace failed to modify "); | |
1489 | print_ip_sym(ip); | |
b17e8a37 | 1490 | print_ip_ins(" actual: ", (unsigned char *)ip); |
b17e8a37 SR |
1491 | printk(KERN_CONT "\n"); |
1492 | break; | |
1493 | case -EPERM: | |
1494 | FTRACE_WARN_ON_ONCE(1); | |
1495 | pr_info("ftrace faulted on writing "); | |
1496 | print_ip_sym(ip); | |
1497 | break; | |
1498 | default: | |
1499 | FTRACE_WARN_ON_ONCE(1); | |
1500 | pr_info("ftrace faulted on unknown error "); | |
1501 | print_ip_sym(ip); | |
1502 | } | |
1503 | } | |
1504 | ||
3c1720f0 | 1505 | |
2cfa1978 MH |
1506 | /* Return 1 if the address range is reserved for ftrace */ |
1507 | int ftrace_text_reserved(void *start, void *end) | |
1508 | { | |
1509 | struct dyn_ftrace *rec; | |
1510 | struct ftrace_page *pg; | |
1511 | ||
1512 | do_for_each_ftrace_rec(pg, rec) { | |
1513 | if (rec->ip <= (unsigned long)end && | |
1514 | rec->ip + MCOUNT_INSN_SIZE > (unsigned long)start) | |
1515 | return 1; | |
1516 | } while_for_each_ftrace_rec(); | |
1517 | return 0; | |
1518 | } | |
1519 | ||
1520 | ||
0eb96701 | 1521 | static int |
31e88909 | 1522 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) |
5072c59f | 1523 | { |
e7d3737e | 1524 | unsigned long ftrace_addr; |
64fbcd16 | 1525 | unsigned long flag = 0UL; |
e7d3737e | 1526 | |
f0001207 | 1527 | ftrace_addr = (unsigned long)FTRACE_ADDR; |
5072c59f | 1528 | |
982c350b | 1529 | /* |
ed926f9b | 1530 | * If we are enabling tracing: |
982c350b | 1531 | * |
ed926f9b SR |
1532 | * If the record has a ref count, then we need to enable it |
1533 | * because someone is using it. | |
982c350b | 1534 | * |
ed926f9b SR |
1535 | * Otherwise we make sure its disabled. |
1536 | * | |
1537 | * If we are disabling tracing, then disable all records that | |
1538 | * are enabled. | |
982c350b | 1539 | */ |
ed926f9b SR |
1540 | if (enable && (rec->flags & ~FTRACE_FL_MASK)) |
1541 | flag = FTRACE_FL_ENABLED; | |
982c350b | 1542 | |
64fbcd16 XG |
1543 | /* If the state of this record hasn't changed, then do nothing */ |
1544 | if ((rec->flags & FTRACE_FL_ENABLED) == flag) | |
1545 | return 0; | |
982c350b | 1546 | |
64fbcd16 XG |
1547 | if (flag) { |
1548 | rec->flags |= FTRACE_FL_ENABLED; | |
1549 | return ftrace_make_call(rec, ftrace_addr); | |
5072c59f SR |
1550 | } |
1551 | ||
64fbcd16 XG |
1552 | rec->flags &= ~FTRACE_FL_ENABLED; |
1553 | return ftrace_make_nop(NULL, rec, ftrace_addr); | |
5072c59f SR |
1554 | } |
1555 | ||
e309b41d | 1556 | static void ftrace_replace_code(int enable) |
3c1720f0 | 1557 | { |
3c1720f0 SR |
1558 | struct dyn_ftrace *rec; |
1559 | struct ftrace_page *pg; | |
6a24a244 | 1560 | int failed; |
3c1720f0 | 1561 | |
45a4a237 SR |
1562 | if (unlikely(ftrace_disabled)) |
1563 | return; | |
1564 | ||
265c831c | 1565 | do_for_each_ftrace_rec(pg, rec) { |
d2c8c3ea SR |
1566 | /* Skip over free records */ |
1567 | if (rec->flags & FTRACE_FL_FREE) | |
265c831c SR |
1568 | continue; |
1569 | ||
265c831c | 1570 | failed = __ftrace_replace_code(rec, enable); |
fa9d13cf | 1571 | if (failed) { |
3279ba37 SR |
1572 | ftrace_bug(failed, rec->ip); |
1573 | /* Stop processing */ | |
1574 | return; | |
3c1720f0 | 1575 | } |
265c831c | 1576 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
1577 | } |
1578 | ||
492a7ea5 | 1579 | static int |
31e88909 | 1580 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 SR |
1581 | { |
1582 | unsigned long ip; | |
593eb8a2 | 1583 | int ret; |
3c1720f0 SR |
1584 | |
1585 | ip = rec->ip; | |
1586 | ||
45a4a237 SR |
1587 | if (unlikely(ftrace_disabled)) |
1588 | return 0; | |
1589 | ||
25aac9dc | 1590 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
593eb8a2 | 1591 | if (ret) { |
31e88909 | 1592 | ftrace_bug(ret, ip); |
492a7ea5 | 1593 | return 0; |
37ad5084 | 1594 | } |
492a7ea5 | 1595 | return 1; |
3c1720f0 SR |
1596 | } |
1597 | ||
000ab691 SR |
1598 | /* |
1599 | * archs can override this function if they must do something | |
1600 | * before the modifying code is performed. | |
1601 | */ | |
1602 | int __weak ftrace_arch_code_modify_prepare(void) | |
1603 | { | |
1604 | return 0; | |
1605 | } | |
1606 | ||
1607 | /* | |
1608 | * archs can override this function if they must do something | |
1609 | * after the modifying code is performed. | |
1610 | */ | |
1611 | int __weak ftrace_arch_code_modify_post_process(void) | |
1612 | { | |
1613 | return 0; | |
1614 | } | |
1615 | ||
e309b41d | 1616 | static int __ftrace_modify_code(void *data) |
3d083395 | 1617 | { |
d61f82d0 SR |
1618 | int *command = data; |
1619 | ||
6331c28c SR |
1620 | /* |
1621 | * Do not call function tracer while we update the code. | |
1622 | * We are in stop machine, no worrying about races. | |
1623 | */ | |
1624 | function_trace_stop++; | |
1625 | ||
a3583244 | 1626 | if (*command & FTRACE_ENABLE_CALLS) |
d61f82d0 | 1627 | ftrace_replace_code(1); |
a3583244 | 1628 | else if (*command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
1629 | ftrace_replace_code(0); |
1630 | ||
1631 | if (*command & FTRACE_UPDATE_TRACE_FUNC) | |
1632 | ftrace_update_ftrace_func(ftrace_trace_function); | |
1633 | ||
5a45cfe1 SR |
1634 | if (*command & FTRACE_START_FUNC_RET) |
1635 | ftrace_enable_ftrace_graph_caller(); | |
1636 | else if (*command & FTRACE_STOP_FUNC_RET) | |
1637 | ftrace_disable_ftrace_graph_caller(); | |
1638 | ||
6331c28c SR |
1639 | #ifndef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
1640 | /* | |
1641 | * For archs that call ftrace_test_stop_func(), we must | |
1642 | * wait till after we update all the function callers | |
1643 | * before we update the callback. This keeps different | |
1644 | * ops that record different functions from corrupting | |
1645 | * each other. | |
1646 | */ | |
1647 | __ftrace_trace_function = __ftrace_trace_function_delay; | |
1648 | #endif | |
1649 | function_trace_stop--; | |
1650 | ||
d61f82d0 | 1651 | return 0; |
3d083395 SR |
1652 | } |
1653 | ||
e309b41d | 1654 | static void ftrace_run_update_code(int command) |
3d083395 | 1655 | { |
000ab691 SR |
1656 | int ret; |
1657 | ||
1658 | ret = ftrace_arch_code_modify_prepare(); | |
1659 | FTRACE_WARN_ON(ret); | |
1660 | if (ret) | |
1661 | return; | |
1662 | ||
784e2d76 | 1663 | stop_machine(__ftrace_modify_code, &command, NULL); |
000ab691 SR |
1664 | |
1665 | ret = ftrace_arch_code_modify_post_process(); | |
1666 | FTRACE_WARN_ON(ret); | |
3d083395 SR |
1667 | } |
1668 | ||
d61f82d0 | 1669 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 1670 | static int ftrace_start_up; |
b848914c | 1671 | static int global_start_up; |
df4fc315 SR |
1672 | |
1673 | static void ftrace_startup_enable(int command) | |
1674 | { | |
1675 | if (saved_ftrace_func != ftrace_trace_function) { | |
1676 | saved_ftrace_func = ftrace_trace_function; | |
1677 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
1678 | } | |
1679 | ||
1680 | if (!command || !ftrace_enabled) | |
1681 | return; | |
1682 | ||
1683 | ftrace_run_update_code(command); | |
1684 | } | |
d61f82d0 | 1685 | |
a1cd6173 | 1686 | static int ftrace_startup(struct ftrace_ops *ops, int command) |
3d083395 | 1687 | { |
b848914c SR |
1688 | bool hash_enable = true; |
1689 | ||
4eebcc81 | 1690 | if (unlikely(ftrace_disabled)) |
a1cd6173 | 1691 | return -ENODEV; |
4eebcc81 | 1692 | |
60a7ecf4 | 1693 | ftrace_start_up++; |
982c350b | 1694 | command |= FTRACE_ENABLE_CALLS; |
d61f82d0 | 1695 | |
b848914c SR |
1696 | /* ops marked global share the filter hashes */ |
1697 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { | |
1698 | ops = &global_ops; | |
1699 | /* Don't update hash if global is already set */ | |
1700 | if (global_start_up) | |
1701 | hash_enable = false; | |
1702 | global_start_up++; | |
1703 | } | |
1704 | ||
ed926f9b | 1705 | ops->flags |= FTRACE_OPS_FL_ENABLED; |
b848914c | 1706 | if (hash_enable) |
ed926f9b SR |
1707 | ftrace_hash_rec_enable(ops, 1); |
1708 | ||
df4fc315 | 1709 | ftrace_startup_enable(command); |
a1cd6173 SR |
1710 | |
1711 | return 0; | |
3d083395 SR |
1712 | } |
1713 | ||
bd69c30b | 1714 | static void ftrace_shutdown(struct ftrace_ops *ops, int command) |
3d083395 | 1715 | { |
b848914c SR |
1716 | bool hash_disable = true; |
1717 | ||
4eebcc81 SR |
1718 | if (unlikely(ftrace_disabled)) |
1719 | return; | |
1720 | ||
60a7ecf4 | 1721 | ftrace_start_up--; |
9ea1a153 FW |
1722 | /* |
1723 | * Just warn in case of unbalance, no need to kill ftrace, it's not | |
1724 | * critical but the ftrace_call callers may be never nopped again after | |
1725 | * further ftrace uses. | |
1726 | */ | |
1727 | WARN_ON_ONCE(ftrace_start_up < 0); | |
1728 | ||
b848914c SR |
1729 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
1730 | ops = &global_ops; | |
1731 | global_start_up--; | |
1732 | WARN_ON_ONCE(global_start_up < 0); | |
1733 | /* Don't update hash if global still has users */ | |
1734 | if (global_start_up) { | |
1735 | WARN_ON_ONCE(!ftrace_start_up); | |
1736 | hash_disable = false; | |
1737 | } | |
1738 | } | |
1739 | ||
1740 | if (hash_disable) | |
ed926f9b SR |
1741 | ftrace_hash_rec_disable(ops, 1); |
1742 | ||
b848914c | 1743 | if (ops != &global_ops || !global_start_up) |
ed926f9b | 1744 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; |
b848914c SR |
1745 | |
1746 | if (!ftrace_start_up) | |
1747 | command |= FTRACE_DISABLE_CALLS; | |
3d083395 | 1748 | |
d61f82d0 SR |
1749 | if (saved_ftrace_func != ftrace_trace_function) { |
1750 | saved_ftrace_func = ftrace_trace_function; | |
1751 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
1752 | } | |
3d083395 | 1753 | |
d61f82d0 | 1754 | if (!command || !ftrace_enabled) |
e6ea44e9 | 1755 | return; |
d61f82d0 SR |
1756 | |
1757 | ftrace_run_update_code(command); | |
3d083395 SR |
1758 | } |
1759 | ||
e309b41d | 1760 | static void ftrace_startup_sysctl(void) |
b0fc494f | 1761 | { |
4eebcc81 SR |
1762 | if (unlikely(ftrace_disabled)) |
1763 | return; | |
1764 | ||
d61f82d0 SR |
1765 | /* Force update next time */ |
1766 | saved_ftrace_func = NULL; | |
60a7ecf4 SR |
1767 | /* ftrace_start_up is true if we want ftrace running */ |
1768 | if (ftrace_start_up) | |
79e406d7 | 1769 | ftrace_run_update_code(FTRACE_ENABLE_CALLS); |
b0fc494f SR |
1770 | } |
1771 | ||
e309b41d | 1772 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 1773 | { |
4eebcc81 SR |
1774 | if (unlikely(ftrace_disabled)) |
1775 | return; | |
1776 | ||
60a7ecf4 SR |
1777 | /* ftrace_start_up is true if ftrace is running */ |
1778 | if (ftrace_start_up) | |
79e406d7 | 1779 | ftrace_run_update_code(FTRACE_DISABLE_CALLS); |
b0fc494f SR |
1780 | } |
1781 | ||
3d083395 SR |
1782 | static cycle_t ftrace_update_time; |
1783 | static unsigned long ftrace_update_cnt; | |
1784 | unsigned long ftrace_update_tot_cnt; | |
1785 | ||
f7bc8b61 SR |
1786 | static int ops_traces_mod(struct ftrace_ops *ops) |
1787 | { | |
1788 | struct ftrace_hash *hash; | |
1789 | ||
1790 | hash = ops->filter_hash; | |
1791 | return !!(!hash || !hash->count); | |
1792 | } | |
1793 | ||
31e88909 | 1794 | static int ftrace_update_code(struct module *mod) |
3d083395 | 1795 | { |
e94142a6 | 1796 | struct dyn_ftrace *p; |
f22f9a89 | 1797 | cycle_t start, stop; |
f7bc8b61 SR |
1798 | unsigned long ref = 0; |
1799 | ||
1800 | /* | |
1801 | * When adding a module, we need to check if tracers are | |
1802 | * currently enabled and if they are set to trace all functions. | |
1803 | * If they are, we need to enable the module functions as well | |
1804 | * as update the reference counts for those function records. | |
1805 | */ | |
1806 | if (mod) { | |
1807 | struct ftrace_ops *ops; | |
1808 | ||
1809 | for (ops = ftrace_ops_list; | |
1810 | ops != &ftrace_list_end; ops = ops->next) { | |
1811 | if (ops->flags & FTRACE_OPS_FL_ENABLED && | |
1812 | ops_traces_mod(ops)) | |
1813 | ref++; | |
1814 | } | |
1815 | } | |
3d083395 | 1816 | |
750ed1a4 | 1817 | start = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
1818 | ftrace_update_cnt = 0; |
1819 | ||
e94142a6 | 1820 | while (ftrace_new_addrs) { |
3d083395 | 1821 | |
08f5ac90 SR |
1822 | /* If something went wrong, bail without enabling anything */ |
1823 | if (unlikely(ftrace_disabled)) | |
1824 | return -1; | |
f22f9a89 | 1825 | |
e94142a6 | 1826 | p = ftrace_new_addrs; |
ee000b7f | 1827 | ftrace_new_addrs = p->newlist; |
f7bc8b61 | 1828 | p->flags = ref; |
f22f9a89 | 1829 | |
5cb084bb | 1830 | /* |
25985edc | 1831 | * Do the initial record conversion from mcount jump |
5cb084bb JO |
1832 | * to the NOP instructions. |
1833 | */ | |
1834 | if (!ftrace_code_disable(mod, p)) { | |
08f5ac90 | 1835 | ftrace_free_rec(p); |
d2c8c3ea SR |
1836 | /* Game over */ |
1837 | break; | |
5cb084bb JO |
1838 | } |
1839 | ||
5cb084bb JO |
1840 | ftrace_update_cnt++; |
1841 | ||
1842 | /* | |
1843 | * If the tracing is enabled, go ahead and enable the record. | |
1844 | * | |
1845 | * The reason not to enable the record immediatelly is the | |
1846 | * inherent check of ftrace_make_nop/ftrace_make_call for | |
1847 | * correct previous instructions. Making first the NOP | |
1848 | * conversion puts the module to the correct state, thus | |
1849 | * passing the ftrace_make_call check. | |
1850 | */ | |
f7bc8b61 | 1851 | if (ftrace_start_up && ref) { |
5cb084bb JO |
1852 | int failed = __ftrace_replace_code(p, 1); |
1853 | if (failed) { | |
1854 | ftrace_bug(failed, p->ip); | |
1855 | ftrace_free_rec(p); | |
1856 | } | |
1857 | } | |
3d083395 SR |
1858 | } |
1859 | ||
750ed1a4 | 1860 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
1861 | ftrace_update_time = stop - start; |
1862 | ftrace_update_tot_cnt += ftrace_update_cnt; | |
1863 | ||
16444a8a ACM |
1864 | return 0; |
1865 | } | |
1866 | ||
68bf21aa | 1867 | static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) |
3c1720f0 SR |
1868 | { |
1869 | struct ftrace_page *pg; | |
1870 | int cnt; | |
1871 | int i; | |
3c1720f0 SR |
1872 | |
1873 | /* allocate a few pages */ | |
1874 | ftrace_pages_start = (void *)get_zeroed_page(GFP_KERNEL); | |
1875 | if (!ftrace_pages_start) | |
1876 | return -1; | |
1877 | ||
1878 | /* | |
1879 | * Allocate a few more pages. | |
1880 | * | |
1881 | * TODO: have some parser search vmlinux before | |
1882 | * final linking to find all calls to ftrace. | |
1883 | * Then we can: | |
1884 | * a) know how many pages to allocate. | |
1885 | * and/or | |
1886 | * b) set up the table then. | |
1887 | * | |
1888 | * The dynamic code is still necessary for | |
1889 | * modules. | |
1890 | */ | |
1891 | ||
1892 | pg = ftrace_pages = ftrace_pages_start; | |
1893 | ||
68bf21aa | 1894 | cnt = num_to_init / ENTRIES_PER_PAGE; |
08f5ac90 | 1895 | pr_info("ftrace: allocating %ld entries in %d pages\n", |
5821e1b7 | 1896 | num_to_init, cnt + 1); |
3c1720f0 SR |
1897 | |
1898 | for (i = 0; i < cnt; i++) { | |
1899 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); | |
1900 | ||
1901 | /* If we fail, we'll try later anyway */ | |
1902 | if (!pg->next) | |
1903 | break; | |
1904 | ||
1905 | pg = pg->next; | |
1906 | } | |
1907 | ||
1908 | return 0; | |
1909 | } | |
1910 | ||
5072c59f SR |
1911 | enum { |
1912 | FTRACE_ITER_FILTER = (1 << 0), | |
689fd8b6 | 1913 | FTRACE_ITER_NOTRACE = (1 << 1), |
3499e461 SR |
1914 | FTRACE_ITER_PRINTALL = (1 << 2), |
1915 | FTRACE_ITER_HASH = (1 << 3), | |
647bcd03 | 1916 | FTRACE_ITER_ENABLED = (1 << 4), |
5072c59f SR |
1917 | }; |
1918 | ||
1919 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ | |
1920 | ||
1921 | struct ftrace_iterator { | |
98c4fd04 | 1922 | loff_t pos; |
4aeb6967 SR |
1923 | loff_t func_pos; |
1924 | struct ftrace_page *pg; | |
1925 | struct dyn_ftrace *func; | |
1926 | struct ftrace_func_probe *probe; | |
1927 | struct trace_parser parser; | |
1cf41dd7 | 1928 | struct ftrace_hash *hash; |
33dc9b12 | 1929 | struct ftrace_ops *ops; |
4aeb6967 SR |
1930 | int hidx; |
1931 | int idx; | |
1932 | unsigned flags; | |
5072c59f SR |
1933 | }; |
1934 | ||
8fc0c701 | 1935 | static void * |
4aeb6967 | 1936 | t_hash_next(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
1937 | { |
1938 | struct ftrace_iterator *iter = m->private; | |
4aeb6967 | 1939 | struct hlist_node *hnd = NULL; |
8fc0c701 SR |
1940 | struct hlist_head *hhd; |
1941 | ||
8fc0c701 | 1942 | (*pos)++; |
98c4fd04 | 1943 | iter->pos = *pos; |
8fc0c701 | 1944 | |
4aeb6967 SR |
1945 | if (iter->probe) |
1946 | hnd = &iter->probe->node; | |
8fc0c701 SR |
1947 | retry: |
1948 | if (iter->hidx >= FTRACE_FUNC_HASHSIZE) | |
1949 | return NULL; | |
1950 | ||
1951 | hhd = &ftrace_func_hash[iter->hidx]; | |
1952 | ||
1953 | if (hlist_empty(hhd)) { | |
1954 | iter->hidx++; | |
1955 | hnd = NULL; | |
1956 | goto retry; | |
1957 | } | |
1958 | ||
1959 | if (!hnd) | |
1960 | hnd = hhd->first; | |
1961 | else { | |
1962 | hnd = hnd->next; | |
1963 | if (!hnd) { | |
1964 | iter->hidx++; | |
1965 | goto retry; | |
1966 | } | |
1967 | } | |
1968 | ||
4aeb6967 SR |
1969 | if (WARN_ON_ONCE(!hnd)) |
1970 | return NULL; | |
1971 | ||
1972 | iter->probe = hlist_entry(hnd, struct ftrace_func_probe, node); | |
1973 | ||
1974 | return iter; | |
8fc0c701 SR |
1975 | } |
1976 | ||
1977 | static void *t_hash_start(struct seq_file *m, loff_t *pos) | |
1978 | { | |
1979 | struct ftrace_iterator *iter = m->private; | |
1980 | void *p = NULL; | |
d82d6244 LZ |
1981 | loff_t l; |
1982 | ||
2bccfffd SR |
1983 | if (iter->func_pos > *pos) |
1984 | return NULL; | |
8fc0c701 | 1985 | |
d82d6244 | 1986 | iter->hidx = 0; |
2bccfffd | 1987 | for (l = 0; l <= (*pos - iter->func_pos); ) { |
4aeb6967 | 1988 | p = t_hash_next(m, &l); |
d82d6244 LZ |
1989 | if (!p) |
1990 | break; | |
1991 | } | |
4aeb6967 SR |
1992 | if (!p) |
1993 | return NULL; | |
1994 | ||
98c4fd04 SR |
1995 | /* Only set this if we have an item */ |
1996 | iter->flags |= FTRACE_ITER_HASH; | |
1997 | ||
4aeb6967 | 1998 | return iter; |
8fc0c701 SR |
1999 | } |
2000 | ||
4aeb6967 SR |
2001 | static int |
2002 | t_hash_show(struct seq_file *m, struct ftrace_iterator *iter) | |
8fc0c701 | 2003 | { |
b6887d79 | 2004 | struct ftrace_func_probe *rec; |
8fc0c701 | 2005 | |
4aeb6967 SR |
2006 | rec = iter->probe; |
2007 | if (WARN_ON_ONCE(!rec)) | |
2008 | return -EIO; | |
8fc0c701 | 2009 | |
809dcf29 SR |
2010 | if (rec->ops->print) |
2011 | return rec->ops->print(m, rec->ip, rec->ops, rec->data); | |
2012 | ||
b375a11a | 2013 | seq_printf(m, "%ps:%ps", (void *)rec->ip, (void *)rec->ops->func); |
8fc0c701 SR |
2014 | |
2015 | if (rec->data) | |
2016 | seq_printf(m, ":%p", rec->data); | |
2017 | seq_putc(m, '\n'); | |
2018 | ||
2019 | return 0; | |
2020 | } | |
2021 | ||
e309b41d | 2022 | static void * |
5072c59f SR |
2023 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2024 | { | |
2025 | struct ftrace_iterator *iter = m->private; | |
f45948e8 | 2026 | struct ftrace_ops *ops = &global_ops; |
5072c59f SR |
2027 | struct dyn_ftrace *rec = NULL; |
2028 | ||
45a4a237 SR |
2029 | if (unlikely(ftrace_disabled)) |
2030 | return NULL; | |
2031 | ||
8fc0c701 | 2032 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 2033 | return t_hash_next(m, pos); |
8fc0c701 | 2034 | |
5072c59f | 2035 | (*pos)++; |
1106b699 | 2036 | iter->pos = iter->func_pos = *pos; |
5072c59f | 2037 | |
0c75a3ed | 2038 | if (iter->flags & FTRACE_ITER_PRINTALL) |
57c072c7 | 2039 | return t_hash_start(m, pos); |
0c75a3ed | 2040 | |
5072c59f SR |
2041 | retry: |
2042 | if (iter->idx >= iter->pg->index) { | |
2043 | if (iter->pg->next) { | |
2044 | iter->pg = iter->pg->next; | |
2045 | iter->idx = 0; | |
2046 | goto retry; | |
2047 | } | |
2048 | } else { | |
2049 | rec = &iter->pg->records[iter->idx++]; | |
a9fdda33 SR |
2050 | if ((rec->flags & FTRACE_FL_FREE) || |
2051 | ||
0183fb1c | 2052 | ((iter->flags & FTRACE_ITER_FILTER) && |
f45948e8 | 2053 | !(ftrace_lookup_ip(ops->filter_hash, rec->ip))) || |
0183fb1c | 2054 | |
41c52c0d | 2055 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
647bcd03 SR |
2056 | !ftrace_lookup_ip(ops->notrace_hash, rec->ip)) || |
2057 | ||
2058 | ((iter->flags & FTRACE_ITER_ENABLED) && | |
2059 | !(rec->flags & ~FTRACE_FL_MASK))) { | |
2060 | ||
5072c59f SR |
2061 | rec = NULL; |
2062 | goto retry; | |
2063 | } | |
2064 | } | |
2065 | ||
4aeb6967 | 2066 | if (!rec) |
57c072c7 | 2067 | return t_hash_start(m, pos); |
4aeb6967 SR |
2068 | |
2069 | iter->func = rec; | |
2070 | ||
2071 | return iter; | |
5072c59f SR |
2072 | } |
2073 | ||
98c4fd04 SR |
2074 | static void reset_iter_read(struct ftrace_iterator *iter) |
2075 | { | |
2076 | iter->pos = 0; | |
2077 | iter->func_pos = 0; | |
2078 | iter->flags &= ~(FTRACE_ITER_PRINTALL & FTRACE_ITER_HASH); | |
5072c59f SR |
2079 | } |
2080 | ||
2081 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2082 | { | |
2083 | struct ftrace_iterator *iter = m->private; | |
f45948e8 | 2084 | struct ftrace_ops *ops = &global_ops; |
5072c59f | 2085 | void *p = NULL; |
694ce0a5 | 2086 | loff_t l; |
5072c59f | 2087 | |
8fc0c701 | 2088 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
2089 | |
2090 | if (unlikely(ftrace_disabled)) | |
2091 | return NULL; | |
2092 | ||
98c4fd04 SR |
2093 | /* |
2094 | * If an lseek was done, then reset and start from beginning. | |
2095 | */ | |
2096 | if (*pos < iter->pos) | |
2097 | reset_iter_read(iter); | |
2098 | ||
0c75a3ed SR |
2099 | /* |
2100 | * For set_ftrace_filter reading, if we have the filter | |
2101 | * off, we can short cut and just print out that all | |
2102 | * functions are enabled. | |
2103 | */ | |
f45948e8 | 2104 | if (iter->flags & FTRACE_ITER_FILTER && !ops->filter_hash->count) { |
0c75a3ed | 2105 | if (*pos > 0) |
8fc0c701 | 2106 | return t_hash_start(m, pos); |
0c75a3ed | 2107 | iter->flags |= FTRACE_ITER_PRINTALL; |
df091625 CW |
2108 | /* reset in case of seek/pread */ |
2109 | iter->flags &= ~FTRACE_ITER_HASH; | |
0c75a3ed SR |
2110 | return iter; |
2111 | } | |
2112 | ||
8fc0c701 SR |
2113 | if (iter->flags & FTRACE_ITER_HASH) |
2114 | return t_hash_start(m, pos); | |
2115 | ||
98c4fd04 SR |
2116 | /* |
2117 | * Unfortunately, we need to restart at ftrace_pages_start | |
2118 | * every time we let go of the ftrace_mutex. This is because | |
2119 | * those pointers can change without the lock. | |
2120 | */ | |
694ce0a5 LZ |
2121 | iter->pg = ftrace_pages_start; |
2122 | iter->idx = 0; | |
2123 | for (l = 0; l <= *pos; ) { | |
2124 | p = t_next(m, p, &l); | |
2125 | if (!p) | |
2126 | break; | |
50cdaf08 | 2127 | } |
5821e1b7 | 2128 | |
4aeb6967 SR |
2129 | if (!p) { |
2130 | if (iter->flags & FTRACE_ITER_FILTER) | |
2131 | return t_hash_start(m, pos); | |
8fc0c701 | 2132 | |
4aeb6967 SR |
2133 | return NULL; |
2134 | } | |
2135 | ||
2136 | return iter; | |
5072c59f SR |
2137 | } |
2138 | ||
2139 | static void t_stop(struct seq_file *m, void *p) | |
2140 | { | |
8fc0c701 | 2141 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
2142 | } |
2143 | ||
2144 | static int t_show(struct seq_file *m, void *v) | |
2145 | { | |
0c75a3ed | 2146 | struct ftrace_iterator *iter = m->private; |
4aeb6967 | 2147 | struct dyn_ftrace *rec; |
5072c59f | 2148 | |
8fc0c701 | 2149 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 2150 | return t_hash_show(m, iter); |
8fc0c701 | 2151 | |
0c75a3ed SR |
2152 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
2153 | seq_printf(m, "#### all functions enabled ####\n"); | |
2154 | return 0; | |
2155 | } | |
2156 | ||
4aeb6967 SR |
2157 | rec = iter->func; |
2158 | ||
5072c59f SR |
2159 | if (!rec) |
2160 | return 0; | |
2161 | ||
647bcd03 SR |
2162 | seq_printf(m, "%ps", (void *)rec->ip); |
2163 | if (iter->flags & FTRACE_ITER_ENABLED) | |
2164 | seq_printf(m, " (%ld)", | |
2165 | rec->flags & ~FTRACE_FL_MASK); | |
2166 | seq_printf(m, "\n"); | |
5072c59f SR |
2167 | |
2168 | return 0; | |
2169 | } | |
2170 | ||
88e9d34c | 2171 | static const struct seq_operations show_ftrace_seq_ops = { |
5072c59f SR |
2172 | .start = t_start, |
2173 | .next = t_next, | |
2174 | .stop = t_stop, | |
2175 | .show = t_show, | |
2176 | }; | |
2177 | ||
e309b41d | 2178 | static int |
5072c59f SR |
2179 | ftrace_avail_open(struct inode *inode, struct file *file) |
2180 | { | |
2181 | struct ftrace_iterator *iter; | |
2182 | int ret; | |
2183 | ||
4eebcc81 SR |
2184 | if (unlikely(ftrace_disabled)) |
2185 | return -ENODEV; | |
2186 | ||
5072c59f SR |
2187 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
2188 | if (!iter) | |
2189 | return -ENOMEM; | |
2190 | ||
2191 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
2192 | |
2193 | ret = seq_open(file, &show_ftrace_seq_ops); | |
2194 | if (!ret) { | |
2195 | struct seq_file *m = file->private_data; | |
4bf39a94 | 2196 | |
5072c59f | 2197 | m->private = iter; |
4bf39a94 | 2198 | } else { |
5072c59f | 2199 | kfree(iter); |
4bf39a94 | 2200 | } |
5072c59f SR |
2201 | |
2202 | return ret; | |
2203 | } | |
2204 | ||
647bcd03 SR |
2205 | static int |
2206 | ftrace_enabled_open(struct inode *inode, struct file *file) | |
2207 | { | |
2208 | struct ftrace_iterator *iter; | |
2209 | int ret; | |
2210 | ||
2211 | if (unlikely(ftrace_disabled)) | |
2212 | return -ENODEV; | |
2213 | ||
2214 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
2215 | if (!iter) | |
2216 | return -ENOMEM; | |
2217 | ||
2218 | iter->pg = ftrace_pages_start; | |
2219 | iter->flags = FTRACE_ITER_ENABLED; | |
2220 | ||
2221 | ret = seq_open(file, &show_ftrace_seq_ops); | |
2222 | if (!ret) { | |
2223 | struct seq_file *m = file->private_data; | |
2224 | ||
2225 | m->private = iter; | |
2226 | } else { | |
2227 | kfree(iter); | |
2228 | } | |
2229 | ||
2230 | return ret; | |
2231 | } | |
2232 | ||
1cf41dd7 | 2233 | static void ftrace_filter_reset(struct ftrace_hash *hash) |
5072c59f | 2234 | { |
52baf119 | 2235 | mutex_lock(&ftrace_lock); |
1cf41dd7 | 2236 | ftrace_hash_clear(hash); |
52baf119 | 2237 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
2238 | } |
2239 | ||
e309b41d | 2240 | static int |
f45948e8 | 2241 | ftrace_regex_open(struct ftrace_ops *ops, int flag, |
1cf41dd7 | 2242 | struct inode *inode, struct file *file) |
5072c59f SR |
2243 | { |
2244 | struct ftrace_iterator *iter; | |
f45948e8 | 2245 | struct ftrace_hash *hash; |
5072c59f SR |
2246 | int ret = 0; |
2247 | ||
4eebcc81 SR |
2248 | if (unlikely(ftrace_disabled)) |
2249 | return -ENODEV; | |
2250 | ||
5072c59f SR |
2251 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
2252 | if (!iter) | |
2253 | return -ENOMEM; | |
2254 | ||
689fd8b6 | 2255 | if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) { |
2256 | kfree(iter); | |
2257 | return -ENOMEM; | |
2258 | } | |
2259 | ||
f45948e8 SR |
2260 | if (flag & FTRACE_ITER_NOTRACE) |
2261 | hash = ops->notrace_hash; | |
2262 | else | |
2263 | hash = ops->filter_hash; | |
2264 | ||
33dc9b12 SR |
2265 | iter->ops = ops; |
2266 | iter->flags = flag; | |
2267 | ||
2268 | if (file->f_mode & FMODE_WRITE) { | |
2269 | mutex_lock(&ftrace_lock); | |
2270 | iter->hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash); | |
2271 | mutex_unlock(&ftrace_lock); | |
2272 | ||
2273 | if (!iter->hash) { | |
2274 | trace_parser_put(&iter->parser); | |
2275 | kfree(iter); | |
2276 | return -ENOMEM; | |
2277 | } | |
2278 | } | |
1cf41dd7 | 2279 | |
41c52c0d | 2280 | mutex_lock(&ftrace_regex_lock); |
33dc9b12 | 2281 | |
5072c59f | 2282 | if ((file->f_mode & FMODE_WRITE) && |
8650ae32 | 2283 | (file->f_flags & O_TRUNC)) |
33dc9b12 | 2284 | ftrace_filter_reset(iter->hash); |
5072c59f SR |
2285 | |
2286 | if (file->f_mode & FMODE_READ) { | |
2287 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
2288 | |
2289 | ret = seq_open(file, &show_ftrace_seq_ops); | |
2290 | if (!ret) { | |
2291 | struct seq_file *m = file->private_data; | |
2292 | m->private = iter; | |
79fe249c | 2293 | } else { |
33dc9b12 SR |
2294 | /* Failed */ |
2295 | free_ftrace_hash(iter->hash); | |
79fe249c | 2296 | trace_parser_put(&iter->parser); |
5072c59f | 2297 | kfree(iter); |
79fe249c | 2298 | } |
5072c59f SR |
2299 | } else |
2300 | file->private_data = iter; | |
41c52c0d | 2301 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
2302 | |
2303 | return ret; | |
2304 | } | |
2305 | ||
41c52c0d SR |
2306 | static int |
2307 | ftrace_filter_open(struct inode *inode, struct file *file) | |
2308 | { | |
f45948e8 | 2309 | return ftrace_regex_open(&global_ops, FTRACE_ITER_FILTER, |
1cf41dd7 | 2310 | inode, file); |
41c52c0d SR |
2311 | } |
2312 | ||
2313 | static int | |
2314 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
2315 | { | |
f45948e8 | 2316 | return ftrace_regex_open(&global_ops, FTRACE_ITER_NOTRACE, |
1cf41dd7 | 2317 | inode, file); |
41c52c0d SR |
2318 | } |
2319 | ||
e309b41d | 2320 | static loff_t |
41c52c0d | 2321 | ftrace_regex_lseek(struct file *file, loff_t offset, int origin) |
5072c59f SR |
2322 | { |
2323 | loff_t ret; | |
2324 | ||
2325 | if (file->f_mode & FMODE_READ) | |
2326 | ret = seq_lseek(file, offset, origin); | |
2327 | else | |
2328 | file->f_pos = ret = 1; | |
2329 | ||
2330 | return ret; | |
2331 | } | |
2332 | ||
64e7c440 | 2333 | static int ftrace_match(char *str, char *regex, int len, int type) |
9f4801e3 | 2334 | { |
9f4801e3 | 2335 | int matched = 0; |
751e9983 | 2336 | int slen; |
9f4801e3 | 2337 | |
9f4801e3 SR |
2338 | switch (type) { |
2339 | case MATCH_FULL: | |
2340 | if (strcmp(str, regex) == 0) | |
2341 | matched = 1; | |
2342 | break; | |
2343 | case MATCH_FRONT_ONLY: | |
2344 | if (strncmp(str, regex, len) == 0) | |
2345 | matched = 1; | |
2346 | break; | |
2347 | case MATCH_MIDDLE_ONLY: | |
2348 | if (strstr(str, regex)) | |
2349 | matched = 1; | |
2350 | break; | |
2351 | case MATCH_END_ONLY: | |
751e9983 LZ |
2352 | slen = strlen(str); |
2353 | if (slen >= len && memcmp(str + slen - len, regex, len) == 0) | |
9f4801e3 SR |
2354 | matched = 1; |
2355 | break; | |
2356 | } | |
2357 | ||
2358 | return matched; | |
2359 | } | |
2360 | ||
b448c4e3 | 2361 | static int |
1cf41dd7 | 2362 | enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int not) |
996e87be | 2363 | { |
b448c4e3 | 2364 | struct ftrace_func_entry *entry; |
b448c4e3 SR |
2365 | int ret = 0; |
2366 | ||
1cf41dd7 SR |
2367 | entry = ftrace_lookup_ip(hash, rec->ip); |
2368 | if (not) { | |
2369 | /* Do nothing if it doesn't exist */ | |
2370 | if (!entry) | |
2371 | return 0; | |
b448c4e3 | 2372 | |
33dc9b12 | 2373 | free_hash_entry(hash, entry); |
1cf41dd7 SR |
2374 | } else { |
2375 | /* Do nothing if it exists */ | |
2376 | if (entry) | |
2377 | return 0; | |
b448c4e3 | 2378 | |
1cf41dd7 | 2379 | ret = add_hash_entry(hash, rec->ip); |
b448c4e3 SR |
2380 | } |
2381 | return ret; | |
996e87be SR |
2382 | } |
2383 | ||
64e7c440 | 2384 | static int |
b9df92d2 SR |
2385 | ftrace_match_record(struct dyn_ftrace *rec, char *mod, |
2386 | char *regex, int len, int type) | |
64e7c440 SR |
2387 | { |
2388 | char str[KSYM_SYMBOL_LEN]; | |
b9df92d2 SR |
2389 | char *modname; |
2390 | ||
2391 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); | |
2392 | ||
2393 | if (mod) { | |
2394 | /* module lookup requires matching the module */ | |
2395 | if (!modname || strcmp(modname, mod)) | |
2396 | return 0; | |
2397 | ||
2398 | /* blank search means to match all funcs in the mod */ | |
2399 | if (!len) | |
2400 | return 1; | |
2401 | } | |
64e7c440 | 2402 | |
64e7c440 SR |
2403 | return ftrace_match(str, regex, len, type); |
2404 | } | |
2405 | ||
1cf41dd7 SR |
2406 | static int |
2407 | match_records(struct ftrace_hash *hash, char *buff, | |
2408 | int len, char *mod, int not) | |
9f4801e3 | 2409 | { |
b9df92d2 | 2410 | unsigned search_len = 0; |
9f4801e3 SR |
2411 | struct ftrace_page *pg; |
2412 | struct dyn_ftrace *rec; | |
b9df92d2 SR |
2413 | int type = MATCH_FULL; |
2414 | char *search = buff; | |
311d16da | 2415 | int found = 0; |
b448c4e3 | 2416 | int ret; |
9f4801e3 | 2417 | |
b9df92d2 SR |
2418 | if (len) { |
2419 | type = filter_parse_regex(buff, len, &search, ¬); | |
2420 | search_len = strlen(search); | |
2421 | } | |
9f4801e3 | 2422 | |
52baf119 | 2423 | mutex_lock(&ftrace_lock); |
265c831c | 2424 | |
b9df92d2 SR |
2425 | if (unlikely(ftrace_disabled)) |
2426 | goto out_unlock; | |
9f4801e3 | 2427 | |
265c831c | 2428 | do_for_each_ftrace_rec(pg, rec) { |
265c831c | 2429 | |
b9df92d2 | 2430 | if (ftrace_match_record(rec, mod, search, search_len, type)) { |
1cf41dd7 | 2431 | ret = enter_record(hash, rec, not); |
b448c4e3 SR |
2432 | if (ret < 0) { |
2433 | found = ret; | |
2434 | goto out_unlock; | |
2435 | } | |
311d16da | 2436 | found = 1; |
265c831c SR |
2437 | } |
2438 | } while_for_each_ftrace_rec(); | |
b9df92d2 | 2439 | out_unlock: |
52baf119 | 2440 | mutex_unlock(&ftrace_lock); |
311d16da LZ |
2441 | |
2442 | return found; | |
5072c59f SR |
2443 | } |
2444 | ||
64e7c440 | 2445 | static int |
1cf41dd7 | 2446 | ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) |
64e7c440 | 2447 | { |
1cf41dd7 | 2448 | return match_records(hash, buff, len, NULL, 0); |
64e7c440 SR |
2449 | } |
2450 | ||
1cf41dd7 SR |
2451 | static int |
2452 | ftrace_match_module_records(struct ftrace_hash *hash, char *buff, char *mod) | |
64e7c440 | 2453 | { |
64e7c440 | 2454 | int not = 0; |
6a24a244 | 2455 | |
64e7c440 SR |
2456 | /* blank or '*' mean the same */ |
2457 | if (strcmp(buff, "*") == 0) | |
2458 | buff[0] = 0; | |
2459 | ||
2460 | /* handle the case of 'dont filter this module' */ | |
2461 | if (strcmp(buff, "!") == 0 || strcmp(buff, "!*") == 0) { | |
2462 | buff[0] = 0; | |
2463 | not = 1; | |
2464 | } | |
2465 | ||
1cf41dd7 | 2466 | return match_records(hash, buff, strlen(buff), mod, not); |
64e7c440 SR |
2467 | } |
2468 | ||
f6180773 SR |
2469 | /* |
2470 | * We register the module command as a template to show others how | |
2471 | * to register the a command as well. | |
2472 | */ | |
2473 | ||
2474 | static int | |
43dd61c9 SR |
2475 | ftrace_mod_callback(struct ftrace_hash *hash, |
2476 | char *func, char *cmd, char *param, int enable) | |
f6180773 SR |
2477 | { |
2478 | char *mod; | |
b448c4e3 | 2479 | int ret = -EINVAL; |
f6180773 SR |
2480 | |
2481 | /* | |
2482 | * cmd == 'mod' because we only registered this func | |
2483 | * for the 'mod' ftrace_func_command. | |
2484 | * But if you register one func with multiple commands, | |
2485 | * you can tell which command was used by the cmd | |
2486 | * parameter. | |
2487 | */ | |
2488 | ||
2489 | /* we must have a module name */ | |
2490 | if (!param) | |
b448c4e3 | 2491 | return ret; |
f6180773 SR |
2492 | |
2493 | mod = strsep(¶m, ":"); | |
2494 | if (!strlen(mod)) | |
b448c4e3 | 2495 | return ret; |
f6180773 | 2496 | |
1cf41dd7 | 2497 | ret = ftrace_match_module_records(hash, func, mod); |
b448c4e3 SR |
2498 | if (!ret) |
2499 | ret = -EINVAL; | |
2500 | if (ret < 0) | |
2501 | return ret; | |
2502 | ||
2503 | return 0; | |
f6180773 SR |
2504 | } |
2505 | ||
2506 | static struct ftrace_func_command ftrace_mod_cmd = { | |
2507 | .name = "mod", | |
2508 | .func = ftrace_mod_callback, | |
2509 | }; | |
2510 | ||
2511 | static int __init ftrace_mod_cmd_init(void) | |
2512 | { | |
2513 | return register_ftrace_command(&ftrace_mod_cmd); | |
2514 | } | |
2515 | device_initcall(ftrace_mod_cmd_init); | |
2516 | ||
59df055f | 2517 | static void |
b6887d79 | 2518 | function_trace_probe_call(unsigned long ip, unsigned long parent_ip) |
59df055f | 2519 | { |
b6887d79 | 2520 | struct ftrace_func_probe *entry; |
59df055f SR |
2521 | struct hlist_head *hhd; |
2522 | struct hlist_node *n; | |
2523 | unsigned long key; | |
59df055f SR |
2524 | |
2525 | key = hash_long(ip, FTRACE_HASH_BITS); | |
2526 | ||
2527 | hhd = &ftrace_func_hash[key]; | |
2528 | ||
2529 | if (hlist_empty(hhd)) | |
2530 | return; | |
2531 | ||
2532 | /* | |
2533 | * Disable preemption for these calls to prevent a RCU grace | |
2534 | * period. This syncs the hash iteration and freeing of items | |
2535 | * on the hash. rcu_read_lock is too dangerous here. | |
2536 | */ | |
5168ae50 | 2537 | preempt_disable_notrace(); |
59df055f SR |
2538 | hlist_for_each_entry_rcu(entry, n, hhd, node) { |
2539 | if (entry->ip == ip) | |
2540 | entry->ops->func(ip, parent_ip, &entry->data); | |
2541 | } | |
5168ae50 | 2542 | preempt_enable_notrace(); |
59df055f SR |
2543 | } |
2544 | ||
b6887d79 | 2545 | static struct ftrace_ops trace_probe_ops __read_mostly = |
59df055f | 2546 | { |
fb9fb015 | 2547 | .func = function_trace_probe_call, |
59df055f SR |
2548 | }; |
2549 | ||
b6887d79 | 2550 | static int ftrace_probe_registered; |
59df055f | 2551 | |
b6887d79 | 2552 | static void __enable_ftrace_function_probe(void) |
59df055f | 2553 | { |
b848914c | 2554 | int ret; |
59df055f SR |
2555 | int i; |
2556 | ||
b6887d79 | 2557 | if (ftrace_probe_registered) |
59df055f SR |
2558 | return; |
2559 | ||
2560 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
2561 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
2562 | if (hhd->first) | |
2563 | break; | |
2564 | } | |
2565 | /* Nothing registered? */ | |
2566 | if (i == FTRACE_FUNC_HASHSIZE) | |
2567 | return; | |
2568 | ||
b848914c SR |
2569 | ret = __register_ftrace_function(&trace_probe_ops); |
2570 | if (!ret) | |
a1cd6173 | 2571 | ret = ftrace_startup(&trace_probe_ops, 0); |
b848914c | 2572 | |
b6887d79 | 2573 | ftrace_probe_registered = 1; |
59df055f SR |
2574 | } |
2575 | ||
b6887d79 | 2576 | static void __disable_ftrace_function_probe(void) |
59df055f | 2577 | { |
b848914c | 2578 | int ret; |
59df055f SR |
2579 | int i; |
2580 | ||
b6887d79 | 2581 | if (!ftrace_probe_registered) |
59df055f SR |
2582 | return; |
2583 | ||
2584 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
2585 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
2586 | if (hhd->first) | |
2587 | return; | |
2588 | } | |
2589 | ||
2590 | /* no more funcs left */ | |
b848914c SR |
2591 | ret = __unregister_ftrace_function(&trace_probe_ops); |
2592 | if (!ret) | |
2593 | ftrace_shutdown(&trace_probe_ops, 0); | |
2594 | ||
b6887d79 | 2595 | ftrace_probe_registered = 0; |
59df055f SR |
2596 | } |
2597 | ||
2598 | ||
2599 | static void ftrace_free_entry_rcu(struct rcu_head *rhp) | |
2600 | { | |
b6887d79 SR |
2601 | struct ftrace_func_probe *entry = |
2602 | container_of(rhp, struct ftrace_func_probe, rcu); | |
59df055f SR |
2603 | |
2604 | if (entry->ops->free) | |
2605 | entry->ops->free(&entry->data); | |
2606 | kfree(entry); | |
2607 | } | |
2608 | ||
2609 | ||
2610 | int | |
b6887d79 | 2611 | register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
2612 | void *data) |
2613 | { | |
b6887d79 | 2614 | struct ftrace_func_probe *entry; |
59df055f SR |
2615 | struct ftrace_page *pg; |
2616 | struct dyn_ftrace *rec; | |
59df055f | 2617 | int type, len, not; |
6a24a244 | 2618 | unsigned long key; |
59df055f SR |
2619 | int count = 0; |
2620 | char *search; | |
2621 | ||
3f6fe06d | 2622 | type = filter_parse_regex(glob, strlen(glob), &search, ¬); |
59df055f SR |
2623 | len = strlen(search); |
2624 | ||
b6887d79 | 2625 | /* we do not support '!' for function probes */ |
59df055f SR |
2626 | if (WARN_ON(not)) |
2627 | return -EINVAL; | |
2628 | ||
2629 | mutex_lock(&ftrace_lock); | |
59df055f | 2630 | |
45a4a237 SR |
2631 | if (unlikely(ftrace_disabled)) |
2632 | goto out_unlock; | |
59df055f | 2633 | |
45a4a237 | 2634 | do_for_each_ftrace_rec(pg, rec) { |
59df055f | 2635 | |
b9df92d2 | 2636 | if (!ftrace_match_record(rec, NULL, search, len, type)) |
59df055f SR |
2637 | continue; |
2638 | ||
2639 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
2640 | if (!entry) { | |
b6887d79 | 2641 | /* If we did not process any, then return error */ |
59df055f SR |
2642 | if (!count) |
2643 | count = -ENOMEM; | |
2644 | goto out_unlock; | |
2645 | } | |
2646 | ||
2647 | count++; | |
2648 | ||
2649 | entry->data = data; | |
2650 | ||
2651 | /* | |
2652 | * The caller might want to do something special | |
2653 | * for each function we find. We call the callback | |
2654 | * to give the caller an opportunity to do so. | |
2655 | */ | |
2656 | if (ops->callback) { | |
2657 | if (ops->callback(rec->ip, &entry->data) < 0) { | |
2658 | /* caller does not like this func */ | |
2659 | kfree(entry); | |
2660 | continue; | |
2661 | } | |
2662 | } | |
2663 | ||
2664 | entry->ops = ops; | |
2665 | entry->ip = rec->ip; | |
2666 | ||
2667 | key = hash_long(entry->ip, FTRACE_HASH_BITS); | |
2668 | hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]); | |
2669 | ||
2670 | } while_for_each_ftrace_rec(); | |
b6887d79 | 2671 | __enable_ftrace_function_probe(); |
59df055f SR |
2672 | |
2673 | out_unlock: | |
2674 | mutex_unlock(&ftrace_lock); | |
2675 | ||
2676 | return count; | |
2677 | } | |
2678 | ||
2679 | enum { | |
b6887d79 SR |
2680 | PROBE_TEST_FUNC = 1, |
2681 | PROBE_TEST_DATA = 2 | |
59df055f SR |
2682 | }; |
2683 | ||
2684 | static void | |
b6887d79 | 2685 | __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
2686 | void *data, int flags) |
2687 | { | |
b6887d79 | 2688 | struct ftrace_func_probe *entry; |
59df055f SR |
2689 | struct hlist_node *n, *tmp; |
2690 | char str[KSYM_SYMBOL_LEN]; | |
2691 | int type = MATCH_FULL; | |
2692 | int i, len = 0; | |
2693 | char *search; | |
2694 | ||
b36461da | 2695 | if (glob && (strcmp(glob, "*") == 0 || !strlen(glob))) |
59df055f | 2696 | glob = NULL; |
b36461da | 2697 | else if (glob) { |
59df055f SR |
2698 | int not; |
2699 | ||
3f6fe06d | 2700 | type = filter_parse_regex(glob, strlen(glob), &search, ¬); |
59df055f SR |
2701 | len = strlen(search); |
2702 | ||
b6887d79 | 2703 | /* we do not support '!' for function probes */ |
59df055f SR |
2704 | if (WARN_ON(not)) |
2705 | return; | |
2706 | } | |
2707 | ||
2708 | mutex_lock(&ftrace_lock); | |
2709 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
2710 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
2711 | ||
2712 | hlist_for_each_entry_safe(entry, n, tmp, hhd, node) { | |
2713 | ||
2714 | /* break up if statements for readability */ | |
b6887d79 | 2715 | if ((flags & PROBE_TEST_FUNC) && entry->ops != ops) |
59df055f SR |
2716 | continue; |
2717 | ||
b6887d79 | 2718 | if ((flags & PROBE_TEST_DATA) && entry->data != data) |
59df055f SR |
2719 | continue; |
2720 | ||
2721 | /* do this last, since it is the most expensive */ | |
2722 | if (glob) { | |
2723 | kallsyms_lookup(entry->ip, NULL, NULL, | |
2724 | NULL, str); | |
2725 | if (!ftrace_match(str, glob, len, type)) | |
2726 | continue; | |
2727 | } | |
2728 | ||
2729 | hlist_del(&entry->node); | |
2730 | call_rcu(&entry->rcu, ftrace_free_entry_rcu); | |
2731 | } | |
2732 | } | |
b6887d79 | 2733 | __disable_ftrace_function_probe(); |
59df055f SR |
2734 | mutex_unlock(&ftrace_lock); |
2735 | } | |
2736 | ||
2737 | void | |
b6887d79 | 2738 | unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
2739 | void *data) |
2740 | { | |
b6887d79 SR |
2741 | __unregister_ftrace_function_probe(glob, ops, data, |
2742 | PROBE_TEST_FUNC | PROBE_TEST_DATA); | |
59df055f SR |
2743 | } |
2744 | ||
2745 | void | |
b6887d79 | 2746 | unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops) |
59df055f | 2747 | { |
b6887d79 | 2748 | __unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC); |
59df055f SR |
2749 | } |
2750 | ||
b6887d79 | 2751 | void unregister_ftrace_function_probe_all(char *glob) |
59df055f | 2752 | { |
b6887d79 | 2753 | __unregister_ftrace_function_probe(glob, NULL, NULL, 0); |
59df055f SR |
2754 | } |
2755 | ||
f6180773 SR |
2756 | static LIST_HEAD(ftrace_commands); |
2757 | static DEFINE_MUTEX(ftrace_cmd_mutex); | |
2758 | ||
2759 | int register_ftrace_command(struct ftrace_func_command *cmd) | |
2760 | { | |
2761 | struct ftrace_func_command *p; | |
2762 | int ret = 0; | |
2763 | ||
2764 | mutex_lock(&ftrace_cmd_mutex); | |
2765 | list_for_each_entry(p, &ftrace_commands, list) { | |
2766 | if (strcmp(cmd->name, p->name) == 0) { | |
2767 | ret = -EBUSY; | |
2768 | goto out_unlock; | |
2769 | } | |
2770 | } | |
2771 | list_add(&cmd->list, &ftrace_commands); | |
2772 | out_unlock: | |
2773 | mutex_unlock(&ftrace_cmd_mutex); | |
2774 | ||
2775 | return ret; | |
2776 | } | |
2777 | ||
2778 | int unregister_ftrace_command(struct ftrace_func_command *cmd) | |
2779 | { | |
2780 | struct ftrace_func_command *p, *n; | |
2781 | int ret = -ENODEV; | |
2782 | ||
2783 | mutex_lock(&ftrace_cmd_mutex); | |
2784 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { | |
2785 | if (strcmp(cmd->name, p->name) == 0) { | |
2786 | ret = 0; | |
2787 | list_del_init(&p->list); | |
2788 | goto out_unlock; | |
2789 | } | |
2790 | } | |
2791 | out_unlock: | |
2792 | mutex_unlock(&ftrace_cmd_mutex); | |
2793 | ||
2794 | return ret; | |
2795 | } | |
2796 | ||
33dc9b12 SR |
2797 | static int ftrace_process_regex(struct ftrace_hash *hash, |
2798 | char *buff, int len, int enable) | |
64e7c440 | 2799 | { |
f6180773 | 2800 | char *func, *command, *next = buff; |
6a24a244 | 2801 | struct ftrace_func_command *p; |
0aff1c0c | 2802 | int ret = -EINVAL; |
64e7c440 SR |
2803 | |
2804 | func = strsep(&next, ":"); | |
2805 | ||
2806 | if (!next) { | |
1cf41dd7 | 2807 | ret = ftrace_match_records(hash, func, len); |
b448c4e3 SR |
2808 | if (!ret) |
2809 | ret = -EINVAL; | |
2810 | if (ret < 0) | |
2811 | return ret; | |
2812 | return 0; | |
64e7c440 SR |
2813 | } |
2814 | ||
f6180773 | 2815 | /* command found */ |
64e7c440 SR |
2816 | |
2817 | command = strsep(&next, ":"); | |
2818 | ||
f6180773 SR |
2819 | mutex_lock(&ftrace_cmd_mutex); |
2820 | list_for_each_entry(p, &ftrace_commands, list) { | |
2821 | if (strcmp(p->name, command) == 0) { | |
43dd61c9 | 2822 | ret = p->func(hash, func, command, next, enable); |
f6180773 SR |
2823 | goto out_unlock; |
2824 | } | |
64e7c440 | 2825 | } |
f6180773 SR |
2826 | out_unlock: |
2827 | mutex_unlock(&ftrace_cmd_mutex); | |
64e7c440 | 2828 | |
f6180773 | 2829 | return ret; |
64e7c440 SR |
2830 | } |
2831 | ||
e309b41d | 2832 | static ssize_t |
41c52c0d SR |
2833 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
2834 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
2835 | { |
2836 | struct ftrace_iterator *iter; | |
689fd8b6 | 2837 | struct trace_parser *parser; |
2838 | ssize_t ret, read; | |
5072c59f | 2839 | |
4ba7978e | 2840 | if (!cnt) |
5072c59f SR |
2841 | return 0; |
2842 | ||
41c52c0d | 2843 | mutex_lock(&ftrace_regex_lock); |
5072c59f | 2844 | |
45a4a237 SR |
2845 | ret = -ENODEV; |
2846 | if (unlikely(ftrace_disabled)) | |
2847 | goto out_unlock; | |
2848 | ||
5072c59f SR |
2849 | if (file->f_mode & FMODE_READ) { |
2850 | struct seq_file *m = file->private_data; | |
2851 | iter = m->private; | |
2852 | } else | |
2853 | iter = file->private_data; | |
2854 | ||
689fd8b6 | 2855 | parser = &iter->parser; |
2856 | read = trace_get_user(parser, ubuf, cnt, ppos); | |
5072c59f | 2857 | |
4ba7978e | 2858 | if (read >= 0 && trace_parser_loaded(parser) && |
689fd8b6 | 2859 | !trace_parser_cont(parser)) { |
33dc9b12 | 2860 | ret = ftrace_process_regex(iter->hash, parser->buffer, |
689fd8b6 | 2861 | parser->idx, enable); |
313254a9 | 2862 | trace_parser_clear(parser); |
5072c59f | 2863 | if (ret) |
ed146b25 | 2864 | goto out_unlock; |
eda1e328 | 2865 | } |
5072c59f | 2866 | |
5072c59f | 2867 | ret = read; |
ed146b25 | 2868 | out_unlock: |
689fd8b6 | 2869 | mutex_unlock(&ftrace_regex_lock); |
ed146b25 | 2870 | |
5072c59f SR |
2871 | return ret; |
2872 | } | |
2873 | ||
41c52c0d SR |
2874 | static ssize_t |
2875 | ftrace_filter_write(struct file *file, const char __user *ubuf, | |
2876 | size_t cnt, loff_t *ppos) | |
2877 | { | |
2878 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
2879 | } | |
2880 | ||
2881 | static ssize_t | |
2882 | ftrace_notrace_write(struct file *file, const char __user *ubuf, | |
2883 | size_t cnt, loff_t *ppos) | |
2884 | { | |
2885 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
2886 | } | |
2887 | ||
33dc9b12 | 2888 | static int |
f45948e8 SR |
2889 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, |
2890 | int reset, int enable) | |
41c52c0d | 2891 | { |
33dc9b12 | 2892 | struct ftrace_hash **orig_hash; |
f45948e8 | 2893 | struct ftrace_hash *hash; |
33dc9b12 | 2894 | int ret; |
f45948e8 | 2895 | |
936e074b SR |
2896 | /* All global ops uses the global ops filters */ |
2897 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) | |
2898 | ops = &global_ops; | |
2899 | ||
41c52c0d | 2900 | if (unlikely(ftrace_disabled)) |
33dc9b12 | 2901 | return -ENODEV; |
41c52c0d | 2902 | |
f45948e8 | 2903 | if (enable) |
33dc9b12 | 2904 | orig_hash = &ops->filter_hash; |
f45948e8 | 2905 | else |
33dc9b12 SR |
2906 | orig_hash = &ops->notrace_hash; |
2907 | ||
2908 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
2909 | if (!hash) | |
2910 | return -ENOMEM; | |
f45948e8 | 2911 | |
41c52c0d SR |
2912 | mutex_lock(&ftrace_regex_lock); |
2913 | if (reset) | |
1cf41dd7 | 2914 | ftrace_filter_reset(hash); |
41c52c0d | 2915 | if (buf) |
1cf41dd7 | 2916 | ftrace_match_records(hash, buf, len); |
33dc9b12 SR |
2917 | |
2918 | mutex_lock(&ftrace_lock); | |
41fb61c2 | 2919 | ret = ftrace_hash_move(ops, enable, orig_hash, hash); |
072126f4 SR |
2920 | if (!ret && ops->flags & FTRACE_OPS_FL_ENABLED |
2921 | && ftrace_enabled) | |
2922 | ftrace_run_update_code(FTRACE_ENABLE_CALLS); | |
2923 | ||
33dc9b12 SR |
2924 | mutex_unlock(&ftrace_lock); |
2925 | ||
41c52c0d | 2926 | mutex_unlock(&ftrace_regex_lock); |
33dc9b12 SR |
2927 | |
2928 | free_ftrace_hash(hash); | |
2929 | return ret; | |
41c52c0d SR |
2930 | } |
2931 | ||
77a2b37d SR |
2932 | /** |
2933 | * ftrace_set_filter - set a function to filter on in ftrace | |
936e074b SR |
2934 | * @ops - the ops to set the filter with |
2935 | * @buf - the string that holds the function filter text. | |
2936 | * @len - the length of the string. | |
2937 | * @reset - non zero to reset all filters before applying this filter. | |
2938 | * | |
2939 | * Filters denote which functions should be enabled when tracing is enabled. | |
2940 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
2941 | */ | |
2942 | void ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, | |
2943 | int len, int reset) | |
2944 | { | |
2945 | ftrace_set_regex(ops, buf, len, reset, 1); | |
2946 | } | |
2947 | EXPORT_SYMBOL_GPL(ftrace_set_filter); | |
2948 | ||
2949 | /** | |
2950 | * ftrace_set_notrace - set a function to not trace in ftrace | |
2951 | * @ops - the ops to set the notrace filter with | |
2952 | * @buf - the string that holds the function notrace text. | |
2953 | * @len - the length of the string. | |
2954 | * @reset - non zero to reset all filters before applying this filter. | |
2955 | * | |
2956 | * Notrace Filters denote which functions should not be enabled when tracing | |
2957 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
2958 | * for tracing. | |
2959 | */ | |
2960 | void ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, | |
2961 | int len, int reset) | |
2962 | { | |
2963 | ftrace_set_regex(ops, buf, len, reset, 0); | |
2964 | } | |
2965 | EXPORT_SYMBOL_GPL(ftrace_set_notrace); | |
2966 | /** | |
2967 | * ftrace_set_filter - set a function to filter on in ftrace | |
2968 | * @ops - the ops to set the filter with | |
77a2b37d SR |
2969 | * @buf - the string that holds the function filter text. |
2970 | * @len - the length of the string. | |
2971 | * @reset - non zero to reset all filters before applying this filter. | |
2972 | * | |
2973 | * Filters denote which functions should be enabled when tracing is enabled. | |
2974 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
2975 | */ | |
936e074b | 2976 | void ftrace_set_global_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 2977 | { |
f45948e8 | 2978 | ftrace_set_regex(&global_ops, buf, len, reset, 1); |
41c52c0d | 2979 | } |
936e074b | 2980 | EXPORT_SYMBOL_GPL(ftrace_set_global_filter); |
4eebcc81 | 2981 | |
41c52c0d SR |
2982 | /** |
2983 | * ftrace_set_notrace - set a function to not trace in ftrace | |
936e074b | 2984 | * @ops - the ops to set the notrace filter with |
41c52c0d SR |
2985 | * @buf - the string that holds the function notrace text. |
2986 | * @len - the length of the string. | |
2987 | * @reset - non zero to reset all filters before applying this filter. | |
2988 | * | |
2989 | * Notrace Filters denote which functions should not be enabled when tracing | |
2990 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
2991 | * for tracing. | |
2992 | */ | |
936e074b | 2993 | void ftrace_set_global_notrace(unsigned char *buf, int len, int reset) |
41c52c0d | 2994 | { |
f45948e8 | 2995 | ftrace_set_regex(&global_ops, buf, len, reset, 0); |
77a2b37d | 2996 | } |
936e074b | 2997 | EXPORT_SYMBOL_GPL(ftrace_set_global_notrace); |
77a2b37d | 2998 | |
2af15d6a SR |
2999 | /* |
3000 | * command line interface to allow users to set filters on boot up. | |
3001 | */ | |
3002 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE | |
3003 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; | |
3004 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; | |
3005 | ||
3006 | static int __init set_ftrace_notrace(char *str) | |
3007 | { | |
3008 | strncpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); | |
3009 | return 1; | |
3010 | } | |
3011 | __setup("ftrace_notrace=", set_ftrace_notrace); | |
3012 | ||
3013 | static int __init set_ftrace_filter(char *str) | |
3014 | { | |
3015 | strncpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); | |
3016 | return 1; | |
3017 | } | |
3018 | __setup("ftrace_filter=", set_ftrace_filter); | |
3019 | ||
369bc18f | 3020 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
f6060f46 | 3021 | static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; |
801c29fd SR |
3022 | static int ftrace_set_func(unsigned long *array, int *idx, char *buffer); |
3023 | ||
369bc18f SA |
3024 | static int __init set_graph_function(char *str) |
3025 | { | |
06f43d66 | 3026 | strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); |
369bc18f SA |
3027 | return 1; |
3028 | } | |
3029 | __setup("ftrace_graph_filter=", set_graph_function); | |
3030 | ||
3031 | static void __init set_ftrace_early_graph(char *buf) | |
3032 | { | |
3033 | int ret; | |
3034 | char *func; | |
3035 | ||
3036 | while (buf) { | |
3037 | func = strsep(&buf, ","); | |
3038 | /* we allow only one expression at a time */ | |
3039 | ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, | |
3040 | func); | |
3041 | if (ret) | |
3042 | printk(KERN_DEBUG "ftrace: function %s not " | |
3043 | "traceable\n", func); | |
3044 | } | |
3045 | } | |
3046 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
3047 | ||
f45948e8 SR |
3048 | static void __init |
3049 | set_ftrace_early_filter(struct ftrace_ops *ops, char *buf, int enable) | |
2af15d6a SR |
3050 | { |
3051 | char *func; | |
3052 | ||
3053 | while (buf) { | |
3054 | func = strsep(&buf, ","); | |
f45948e8 | 3055 | ftrace_set_regex(ops, func, strlen(func), 0, enable); |
2af15d6a SR |
3056 | } |
3057 | } | |
3058 | ||
3059 | static void __init set_ftrace_early_filters(void) | |
3060 | { | |
3061 | if (ftrace_filter_buf[0]) | |
f45948e8 | 3062 | set_ftrace_early_filter(&global_ops, ftrace_filter_buf, 1); |
2af15d6a | 3063 | if (ftrace_notrace_buf[0]) |
f45948e8 | 3064 | set_ftrace_early_filter(&global_ops, ftrace_notrace_buf, 0); |
369bc18f SA |
3065 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
3066 | if (ftrace_graph_buf[0]) | |
3067 | set_ftrace_early_graph(ftrace_graph_buf); | |
3068 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
2af15d6a SR |
3069 | } |
3070 | ||
e309b41d | 3071 | static int |
1cf41dd7 | 3072 | ftrace_regex_release(struct inode *inode, struct file *file) |
5072c59f SR |
3073 | { |
3074 | struct seq_file *m = (struct seq_file *)file->private_data; | |
3075 | struct ftrace_iterator *iter; | |
33dc9b12 | 3076 | struct ftrace_hash **orig_hash; |
689fd8b6 | 3077 | struct trace_parser *parser; |
ed926f9b | 3078 | int filter_hash; |
33dc9b12 | 3079 | int ret; |
5072c59f | 3080 | |
41c52c0d | 3081 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
3082 | if (file->f_mode & FMODE_READ) { |
3083 | iter = m->private; | |
3084 | ||
3085 | seq_release(inode, file); | |
3086 | } else | |
3087 | iter = file->private_data; | |
3088 | ||
689fd8b6 | 3089 | parser = &iter->parser; |
3090 | if (trace_parser_loaded(parser)) { | |
3091 | parser->buffer[parser->idx] = 0; | |
1cf41dd7 | 3092 | ftrace_match_records(iter->hash, parser->buffer, parser->idx); |
5072c59f SR |
3093 | } |
3094 | ||
689fd8b6 | 3095 | trace_parser_put(parser); |
689fd8b6 | 3096 | |
058e297d | 3097 | if (file->f_mode & FMODE_WRITE) { |
ed926f9b SR |
3098 | filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); |
3099 | ||
3100 | if (filter_hash) | |
33dc9b12 | 3101 | orig_hash = &iter->ops->filter_hash; |
ed926f9b SR |
3102 | else |
3103 | orig_hash = &iter->ops->notrace_hash; | |
33dc9b12 | 3104 | |
058e297d | 3105 | mutex_lock(&ftrace_lock); |
41fb61c2 SR |
3106 | ret = ftrace_hash_move(iter->ops, filter_hash, |
3107 | orig_hash, iter->hash); | |
3108 | if (!ret && (iter->ops->flags & FTRACE_OPS_FL_ENABLED) | |
3109 | && ftrace_enabled) | |
3110 | ftrace_run_update_code(FTRACE_ENABLE_CALLS); | |
3111 | ||
058e297d SR |
3112 | mutex_unlock(&ftrace_lock); |
3113 | } | |
33dc9b12 SR |
3114 | free_ftrace_hash(iter->hash); |
3115 | kfree(iter); | |
058e297d | 3116 | |
41c52c0d | 3117 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
3118 | return 0; |
3119 | } | |
3120 | ||
5e2336a0 | 3121 | static const struct file_operations ftrace_avail_fops = { |
5072c59f SR |
3122 | .open = ftrace_avail_open, |
3123 | .read = seq_read, | |
3124 | .llseek = seq_lseek, | |
3be04b47 | 3125 | .release = seq_release_private, |
5072c59f SR |
3126 | }; |
3127 | ||
647bcd03 SR |
3128 | static const struct file_operations ftrace_enabled_fops = { |
3129 | .open = ftrace_enabled_open, | |
3130 | .read = seq_read, | |
3131 | .llseek = seq_lseek, | |
3132 | .release = seq_release_private, | |
3133 | }; | |
3134 | ||
5e2336a0 | 3135 | static const struct file_operations ftrace_filter_fops = { |
5072c59f | 3136 | .open = ftrace_filter_open, |
850a80cf | 3137 | .read = seq_read, |
5072c59f | 3138 | .write = ftrace_filter_write, |
98c4fd04 | 3139 | .llseek = ftrace_regex_lseek, |
1cf41dd7 | 3140 | .release = ftrace_regex_release, |
5072c59f SR |
3141 | }; |
3142 | ||
5e2336a0 | 3143 | static const struct file_operations ftrace_notrace_fops = { |
41c52c0d | 3144 | .open = ftrace_notrace_open, |
850a80cf | 3145 | .read = seq_read, |
41c52c0d SR |
3146 | .write = ftrace_notrace_write, |
3147 | .llseek = ftrace_regex_lseek, | |
1cf41dd7 | 3148 | .release = ftrace_regex_release, |
41c52c0d SR |
3149 | }; |
3150 | ||
ea4e2bc4 SR |
3151 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
3152 | ||
3153 | static DEFINE_MUTEX(graph_lock); | |
3154 | ||
3155 | int ftrace_graph_count; | |
c7c6b1fe | 3156 | int ftrace_graph_filter_enabled; |
ea4e2bc4 SR |
3157 | unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; |
3158 | ||
3159 | static void * | |
85951842 | 3160 | __g_next(struct seq_file *m, loff_t *pos) |
ea4e2bc4 | 3161 | { |
85951842 | 3162 | if (*pos >= ftrace_graph_count) |
ea4e2bc4 | 3163 | return NULL; |
a4ec5e0c | 3164 | return &ftrace_graph_funcs[*pos]; |
85951842 | 3165 | } |
ea4e2bc4 | 3166 | |
85951842 LZ |
3167 | static void * |
3168 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
3169 | { | |
3170 | (*pos)++; | |
3171 | return __g_next(m, pos); | |
ea4e2bc4 SR |
3172 | } |
3173 | ||
3174 | static void *g_start(struct seq_file *m, loff_t *pos) | |
3175 | { | |
ea4e2bc4 SR |
3176 | mutex_lock(&graph_lock); |
3177 | ||
f9349a8f | 3178 | /* Nothing, tell g_show to print all functions are enabled */ |
c7c6b1fe | 3179 | if (!ftrace_graph_filter_enabled && !*pos) |
f9349a8f FW |
3180 | return (void *)1; |
3181 | ||
85951842 | 3182 | return __g_next(m, pos); |
ea4e2bc4 SR |
3183 | } |
3184 | ||
3185 | static void g_stop(struct seq_file *m, void *p) | |
3186 | { | |
3187 | mutex_unlock(&graph_lock); | |
3188 | } | |
3189 | ||
3190 | static int g_show(struct seq_file *m, void *v) | |
3191 | { | |
3192 | unsigned long *ptr = v; | |
ea4e2bc4 SR |
3193 | |
3194 | if (!ptr) | |
3195 | return 0; | |
3196 | ||
f9349a8f FW |
3197 | if (ptr == (unsigned long *)1) { |
3198 | seq_printf(m, "#### all functions enabled ####\n"); | |
3199 | return 0; | |
3200 | } | |
3201 | ||
b375a11a | 3202 | seq_printf(m, "%ps\n", (void *)*ptr); |
ea4e2bc4 SR |
3203 | |
3204 | return 0; | |
3205 | } | |
3206 | ||
88e9d34c | 3207 | static const struct seq_operations ftrace_graph_seq_ops = { |
ea4e2bc4 SR |
3208 | .start = g_start, |
3209 | .next = g_next, | |
3210 | .stop = g_stop, | |
3211 | .show = g_show, | |
3212 | }; | |
3213 | ||
3214 | static int | |
3215 | ftrace_graph_open(struct inode *inode, struct file *file) | |
3216 | { | |
3217 | int ret = 0; | |
3218 | ||
3219 | if (unlikely(ftrace_disabled)) | |
3220 | return -ENODEV; | |
3221 | ||
3222 | mutex_lock(&graph_lock); | |
3223 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 3224 | (file->f_flags & O_TRUNC)) { |
c7c6b1fe | 3225 | ftrace_graph_filter_enabled = 0; |
ea4e2bc4 SR |
3226 | ftrace_graph_count = 0; |
3227 | memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); | |
3228 | } | |
a4ec5e0c | 3229 | mutex_unlock(&graph_lock); |
ea4e2bc4 | 3230 | |
a4ec5e0c | 3231 | if (file->f_mode & FMODE_READ) |
ea4e2bc4 | 3232 | ret = seq_open(file, &ftrace_graph_seq_ops); |
ea4e2bc4 SR |
3233 | |
3234 | return ret; | |
3235 | } | |
3236 | ||
87827111 LZ |
3237 | static int |
3238 | ftrace_graph_release(struct inode *inode, struct file *file) | |
3239 | { | |
3240 | if (file->f_mode & FMODE_READ) | |
3241 | seq_release(inode, file); | |
3242 | return 0; | |
3243 | } | |
3244 | ||
ea4e2bc4 | 3245 | static int |
f9349a8f | 3246 | ftrace_set_func(unsigned long *array, int *idx, char *buffer) |
ea4e2bc4 | 3247 | { |
ea4e2bc4 SR |
3248 | struct dyn_ftrace *rec; |
3249 | struct ftrace_page *pg; | |
f9349a8f | 3250 | int search_len; |
c7c6b1fe | 3251 | int fail = 1; |
f9349a8f FW |
3252 | int type, not; |
3253 | char *search; | |
3254 | bool exists; | |
3255 | int i; | |
ea4e2bc4 | 3256 | |
f9349a8f | 3257 | /* decode regex */ |
3f6fe06d | 3258 | type = filter_parse_regex(buffer, strlen(buffer), &search, ¬); |
c7c6b1fe LZ |
3259 | if (!not && *idx >= FTRACE_GRAPH_MAX_FUNCS) |
3260 | return -EBUSY; | |
f9349a8f FW |
3261 | |
3262 | search_len = strlen(search); | |
3263 | ||
52baf119 | 3264 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
3265 | |
3266 | if (unlikely(ftrace_disabled)) { | |
3267 | mutex_unlock(&ftrace_lock); | |
3268 | return -ENODEV; | |
3269 | } | |
3270 | ||
265c831c SR |
3271 | do_for_each_ftrace_rec(pg, rec) { |
3272 | ||
45a4a237 | 3273 | if (rec->flags & FTRACE_FL_FREE) |
265c831c SR |
3274 | continue; |
3275 | ||
b9df92d2 | 3276 | if (ftrace_match_record(rec, NULL, search, search_len, type)) { |
c7c6b1fe | 3277 | /* if it is in the array */ |
f9349a8f | 3278 | exists = false; |
c7c6b1fe | 3279 | for (i = 0; i < *idx; i++) { |
f9349a8f FW |
3280 | if (array[i] == rec->ip) { |
3281 | exists = true; | |
265c831c SR |
3282 | break; |
3283 | } | |
c7c6b1fe LZ |
3284 | } |
3285 | ||
3286 | if (!not) { | |
3287 | fail = 0; | |
3288 | if (!exists) { | |
3289 | array[(*idx)++] = rec->ip; | |
3290 | if (*idx >= FTRACE_GRAPH_MAX_FUNCS) | |
3291 | goto out; | |
3292 | } | |
3293 | } else { | |
3294 | if (exists) { | |
3295 | array[i] = array[--(*idx)]; | |
3296 | array[*idx] = 0; | |
3297 | fail = 0; | |
3298 | } | |
3299 | } | |
ea4e2bc4 | 3300 | } |
265c831c | 3301 | } while_for_each_ftrace_rec(); |
c7c6b1fe | 3302 | out: |
52baf119 | 3303 | mutex_unlock(&ftrace_lock); |
ea4e2bc4 | 3304 | |
c7c6b1fe LZ |
3305 | if (fail) |
3306 | return -EINVAL; | |
3307 | ||
3308 | ftrace_graph_filter_enabled = 1; | |
3309 | return 0; | |
ea4e2bc4 SR |
3310 | } |
3311 | ||
3312 | static ssize_t | |
3313 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
3314 | size_t cnt, loff_t *ppos) | |
3315 | { | |
689fd8b6 | 3316 | struct trace_parser parser; |
4ba7978e | 3317 | ssize_t read, ret; |
ea4e2bc4 | 3318 | |
c7c6b1fe | 3319 | if (!cnt) |
ea4e2bc4 SR |
3320 | return 0; |
3321 | ||
3322 | mutex_lock(&graph_lock); | |
3323 | ||
689fd8b6 | 3324 | if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) { |
3325 | ret = -ENOMEM; | |
1eb90f13 | 3326 | goto out_unlock; |
ea4e2bc4 SR |
3327 | } |
3328 | ||
689fd8b6 | 3329 | read = trace_get_user(&parser, ubuf, cnt, ppos); |
ea4e2bc4 | 3330 | |
4ba7978e | 3331 | if (read >= 0 && trace_parser_loaded((&parser))) { |
689fd8b6 | 3332 | parser.buffer[parser.idx] = 0; |
3333 | ||
3334 | /* we allow only one expression at a time */ | |
a4ec5e0c | 3335 | ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, |
689fd8b6 | 3336 | parser.buffer); |
ea4e2bc4 | 3337 | if (ret) |
1eb90f13 | 3338 | goto out_free; |
ea4e2bc4 | 3339 | } |
ea4e2bc4 SR |
3340 | |
3341 | ret = read; | |
1eb90f13 LZ |
3342 | |
3343 | out_free: | |
689fd8b6 | 3344 | trace_parser_put(&parser); |
1eb90f13 | 3345 | out_unlock: |
ea4e2bc4 SR |
3346 | mutex_unlock(&graph_lock); |
3347 | ||
3348 | return ret; | |
3349 | } | |
3350 | ||
3351 | static const struct file_operations ftrace_graph_fops = { | |
87827111 LZ |
3352 | .open = ftrace_graph_open, |
3353 | .read = seq_read, | |
3354 | .write = ftrace_graph_write, | |
3355 | .release = ftrace_graph_release, | |
6038f373 | 3356 | .llseek = seq_lseek, |
ea4e2bc4 SR |
3357 | }; |
3358 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
3359 | ||
df4fc315 | 3360 | static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) |
5072c59f | 3361 | { |
5072c59f | 3362 | |
5452af66 FW |
3363 | trace_create_file("available_filter_functions", 0444, |
3364 | d_tracer, NULL, &ftrace_avail_fops); | |
5072c59f | 3365 | |
647bcd03 SR |
3366 | trace_create_file("enabled_functions", 0444, |
3367 | d_tracer, NULL, &ftrace_enabled_fops); | |
3368 | ||
5452af66 FW |
3369 | trace_create_file("set_ftrace_filter", 0644, d_tracer, |
3370 | NULL, &ftrace_filter_fops); | |
41c52c0d | 3371 | |
5452af66 | 3372 | trace_create_file("set_ftrace_notrace", 0644, d_tracer, |
41c52c0d | 3373 | NULL, &ftrace_notrace_fops); |
ad90c0e3 | 3374 | |
ea4e2bc4 | 3375 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5452af66 | 3376 | trace_create_file("set_graph_function", 0444, d_tracer, |
ea4e2bc4 SR |
3377 | NULL, |
3378 | &ftrace_graph_fops); | |
ea4e2bc4 SR |
3379 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
3380 | ||
5072c59f SR |
3381 | return 0; |
3382 | } | |
3383 | ||
5cb084bb | 3384 | static int ftrace_process_locs(struct module *mod, |
31e88909 | 3385 | unsigned long *start, |
68bf21aa SR |
3386 | unsigned long *end) |
3387 | { | |
3388 | unsigned long *p; | |
3389 | unsigned long addr; | |
4376cac6 | 3390 | unsigned long flags = 0; /* Shut up gcc */ |
68bf21aa | 3391 | |
e6ea44e9 | 3392 | mutex_lock(&ftrace_lock); |
68bf21aa SR |
3393 | p = start; |
3394 | while (p < end) { | |
3395 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
3396 | /* |
3397 | * Some architecture linkers will pad between | |
3398 | * the different mcount_loc sections of different | |
3399 | * object files to satisfy alignments. | |
3400 | * Skip any NULL pointers. | |
3401 | */ | |
3402 | if (!addr) | |
3403 | continue; | |
68bf21aa | 3404 | ftrace_record_ip(addr); |
68bf21aa SR |
3405 | } |
3406 | ||
a4f18ed1 | 3407 | /* |
4376cac6 SR |
3408 | * We only need to disable interrupts on start up |
3409 | * because we are modifying code that an interrupt | |
3410 | * may execute, and the modification is not atomic. | |
3411 | * But for modules, nothing runs the code we modify | |
3412 | * until we are finished with it, and there's no | |
3413 | * reason to cause large interrupt latencies while we do it. | |
a4f18ed1 | 3414 | */ |
4376cac6 SR |
3415 | if (!mod) |
3416 | local_irq_save(flags); | |
31e88909 | 3417 | ftrace_update_code(mod); |
4376cac6 SR |
3418 | if (!mod) |
3419 | local_irq_restore(flags); | |
e6ea44e9 | 3420 | mutex_unlock(&ftrace_lock); |
68bf21aa SR |
3421 | |
3422 | return 0; | |
3423 | } | |
3424 | ||
93eb677d | 3425 | #ifdef CONFIG_MODULES |
e7247a15 | 3426 | void ftrace_release_mod(struct module *mod) |
93eb677d SR |
3427 | { |
3428 | struct dyn_ftrace *rec; | |
3429 | struct ftrace_page *pg; | |
93eb677d | 3430 | |
45a4a237 SR |
3431 | mutex_lock(&ftrace_lock); |
3432 | ||
e7247a15 | 3433 | if (ftrace_disabled) |
45a4a237 | 3434 | goto out_unlock; |
93eb677d | 3435 | |
93eb677d | 3436 | do_for_each_ftrace_rec(pg, rec) { |
e7247a15 | 3437 | if (within_module_core(rec->ip, mod)) { |
93eb677d SR |
3438 | /* |
3439 | * rec->ip is changed in ftrace_free_rec() | |
3440 | * It should not between s and e if record was freed. | |
3441 | */ | |
3442 | FTRACE_WARN_ON(rec->flags & FTRACE_FL_FREE); | |
3443 | ftrace_free_rec(rec); | |
3444 | } | |
3445 | } while_for_each_ftrace_rec(); | |
45a4a237 | 3446 | out_unlock: |
93eb677d SR |
3447 | mutex_unlock(&ftrace_lock); |
3448 | } | |
3449 | ||
3450 | static void ftrace_init_module(struct module *mod, | |
3451 | unsigned long *start, unsigned long *end) | |
90d595fe | 3452 | { |
00fd61ae | 3453 | if (ftrace_disabled || start == end) |
fed1939c | 3454 | return; |
5cb084bb | 3455 | ftrace_process_locs(mod, start, end); |
90d595fe SR |
3456 | } |
3457 | ||
93eb677d SR |
3458 | static int ftrace_module_notify(struct notifier_block *self, |
3459 | unsigned long val, void *data) | |
3460 | { | |
3461 | struct module *mod = data; | |
3462 | ||
3463 | switch (val) { | |
3464 | case MODULE_STATE_COMING: | |
3465 | ftrace_init_module(mod, mod->ftrace_callsites, | |
3466 | mod->ftrace_callsites + | |
3467 | mod->num_ftrace_callsites); | |
3468 | break; | |
3469 | case MODULE_STATE_GOING: | |
e7247a15 | 3470 | ftrace_release_mod(mod); |
93eb677d SR |
3471 | break; |
3472 | } | |
3473 | ||
3474 | return 0; | |
3475 | } | |
3476 | #else | |
3477 | static int ftrace_module_notify(struct notifier_block *self, | |
3478 | unsigned long val, void *data) | |
3479 | { | |
3480 | return 0; | |
3481 | } | |
3482 | #endif /* CONFIG_MODULES */ | |
3483 | ||
3484 | struct notifier_block ftrace_module_nb = { | |
3485 | .notifier_call = ftrace_module_notify, | |
3486 | .priority = 0, | |
3487 | }; | |
3488 | ||
68bf21aa SR |
3489 | extern unsigned long __start_mcount_loc[]; |
3490 | extern unsigned long __stop_mcount_loc[]; | |
3491 | ||
3492 | void __init ftrace_init(void) | |
3493 | { | |
3494 | unsigned long count, addr, flags; | |
3495 | int ret; | |
3496 | ||
3497 | /* Keep the ftrace pointer to the stub */ | |
3498 | addr = (unsigned long)ftrace_stub; | |
3499 | ||
3500 | local_irq_save(flags); | |
3501 | ftrace_dyn_arch_init(&addr); | |
3502 | local_irq_restore(flags); | |
3503 | ||
3504 | /* ftrace_dyn_arch_init places the return code in addr */ | |
3505 | if (addr) | |
3506 | goto failed; | |
3507 | ||
3508 | count = __stop_mcount_loc - __start_mcount_loc; | |
3509 | ||
3510 | ret = ftrace_dyn_table_alloc(count); | |
3511 | if (ret) | |
3512 | goto failed; | |
3513 | ||
3514 | last_ftrace_enabled = ftrace_enabled = 1; | |
3515 | ||
5cb084bb | 3516 | ret = ftrace_process_locs(NULL, |
31e88909 | 3517 | __start_mcount_loc, |
68bf21aa SR |
3518 | __stop_mcount_loc); |
3519 | ||
93eb677d | 3520 | ret = register_module_notifier(&ftrace_module_nb); |
24ed0c4b | 3521 | if (ret) |
93eb677d SR |
3522 | pr_warning("Failed to register trace ftrace module notifier\n"); |
3523 | ||
2af15d6a SR |
3524 | set_ftrace_early_filters(); |
3525 | ||
68bf21aa SR |
3526 | return; |
3527 | failed: | |
3528 | ftrace_disabled = 1; | |
3529 | } | |
68bf21aa | 3530 | |
3d083395 | 3531 | #else |
0b6e4d56 | 3532 | |
2b499381 | 3533 | static struct ftrace_ops global_ops = { |
bd69c30b SR |
3534 | .func = ftrace_stub, |
3535 | }; | |
3536 | ||
0b6e4d56 FW |
3537 | static int __init ftrace_nodyn_init(void) |
3538 | { | |
3539 | ftrace_enabled = 1; | |
3540 | return 0; | |
3541 | } | |
3542 | device_initcall(ftrace_nodyn_init); | |
3543 | ||
df4fc315 SR |
3544 | static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } |
3545 | static inline void ftrace_startup_enable(int command) { } | |
5a45cfe1 | 3546 | /* Keep as macros so we do not need to define the commands */ |
3b6cfdb1 SR |
3547 | # define ftrace_startup(ops, command) \ |
3548 | ({ \ | |
3549 | (ops)->flags |= FTRACE_OPS_FL_ENABLED; \ | |
3550 | 0; \ | |
3551 | }) | |
bd69c30b | 3552 | # define ftrace_shutdown(ops, command) do { } while (0) |
c7aafc54 IM |
3553 | # define ftrace_startup_sysctl() do { } while (0) |
3554 | # define ftrace_shutdown_sysctl() do { } while (0) | |
b848914c SR |
3555 | |
3556 | static inline int | |
3557 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip) | |
3558 | { | |
3559 | return 1; | |
3560 | } | |
3561 | ||
3d083395 SR |
3562 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
3563 | ||
b848914c SR |
3564 | static void |
3565 | ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip) | |
3566 | { | |
cdbe61bf | 3567 | struct ftrace_ops *op; |
b848914c | 3568 | |
b1cff0ad SR |
3569 | if (unlikely(trace_recursion_test(TRACE_INTERNAL_BIT))) |
3570 | return; | |
3571 | ||
3572 | trace_recursion_set(TRACE_INTERNAL_BIT); | |
cdbe61bf SR |
3573 | /* |
3574 | * Some of the ops may be dynamically allocated, | |
3575 | * they must be freed after a synchronize_sched(). | |
3576 | */ | |
3577 | preempt_disable_notrace(); | |
3578 | op = rcu_dereference_raw(ftrace_ops_list); | |
b848914c SR |
3579 | while (op != &ftrace_list_end) { |
3580 | if (ftrace_ops_test(op, ip)) | |
3581 | op->func(ip, parent_ip); | |
3582 | op = rcu_dereference_raw(op->next); | |
3583 | }; | |
cdbe61bf | 3584 | preempt_enable_notrace(); |
b1cff0ad | 3585 | trace_recursion_clear(TRACE_INTERNAL_BIT); |
b848914c SR |
3586 | } |
3587 | ||
e32d8956 | 3588 | static void clear_ftrace_swapper(void) |
978f3a45 SR |
3589 | { |
3590 | struct task_struct *p; | |
e32d8956 | 3591 | int cpu; |
978f3a45 | 3592 | |
e32d8956 SR |
3593 | get_online_cpus(); |
3594 | for_each_online_cpu(cpu) { | |
3595 | p = idle_task(cpu); | |
978f3a45 | 3596 | clear_tsk_trace_trace(p); |
e32d8956 SR |
3597 | } |
3598 | put_online_cpus(); | |
3599 | } | |
978f3a45 | 3600 | |
e32d8956 SR |
3601 | static void set_ftrace_swapper(void) |
3602 | { | |
3603 | struct task_struct *p; | |
3604 | int cpu; | |
3605 | ||
3606 | get_online_cpus(); | |
3607 | for_each_online_cpu(cpu) { | |
3608 | p = idle_task(cpu); | |
3609 | set_tsk_trace_trace(p); | |
3610 | } | |
3611 | put_online_cpus(); | |
978f3a45 SR |
3612 | } |
3613 | ||
e32d8956 SR |
3614 | static void clear_ftrace_pid(struct pid *pid) |
3615 | { | |
3616 | struct task_struct *p; | |
3617 | ||
229c4ef8 | 3618 | rcu_read_lock(); |
e32d8956 SR |
3619 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
3620 | clear_tsk_trace_trace(p); | |
3621 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 ON |
3622 | rcu_read_unlock(); |
3623 | ||
e32d8956 SR |
3624 | put_pid(pid); |
3625 | } | |
3626 | ||
3627 | static void set_ftrace_pid(struct pid *pid) | |
978f3a45 SR |
3628 | { |
3629 | struct task_struct *p; | |
3630 | ||
229c4ef8 | 3631 | rcu_read_lock(); |
978f3a45 SR |
3632 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
3633 | set_tsk_trace_trace(p); | |
3634 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 | 3635 | rcu_read_unlock(); |
978f3a45 SR |
3636 | } |
3637 | ||
756d17ee | 3638 | static void clear_ftrace_pid_task(struct pid *pid) |
e32d8956 | 3639 | { |
756d17ee | 3640 | if (pid == ftrace_swapper_pid) |
e32d8956 SR |
3641 | clear_ftrace_swapper(); |
3642 | else | |
756d17ee | 3643 | clear_ftrace_pid(pid); |
e32d8956 SR |
3644 | } |
3645 | ||
3646 | static void set_ftrace_pid_task(struct pid *pid) | |
3647 | { | |
3648 | if (pid == ftrace_swapper_pid) | |
3649 | set_ftrace_swapper(); | |
3650 | else | |
3651 | set_ftrace_pid(pid); | |
3652 | } | |
3653 | ||
756d17ee | 3654 | static int ftrace_pid_add(int p) |
df4fc315 | 3655 | { |
978f3a45 | 3656 | struct pid *pid; |
756d17ee | 3657 | struct ftrace_pid *fpid; |
3658 | int ret = -EINVAL; | |
df4fc315 | 3659 | |
756d17ee | 3660 | mutex_lock(&ftrace_lock); |
df4fc315 | 3661 | |
756d17ee | 3662 | if (!p) |
3663 | pid = ftrace_swapper_pid; | |
3664 | else | |
3665 | pid = find_get_pid(p); | |
df4fc315 | 3666 | |
756d17ee | 3667 | if (!pid) |
3668 | goto out; | |
df4fc315 | 3669 | |
756d17ee | 3670 | ret = 0; |
df4fc315 | 3671 | |
756d17ee | 3672 | list_for_each_entry(fpid, &ftrace_pids, list) |
3673 | if (fpid->pid == pid) | |
3674 | goto out_put; | |
978f3a45 | 3675 | |
756d17ee | 3676 | ret = -ENOMEM; |
df4fc315 | 3677 | |
756d17ee | 3678 | fpid = kmalloc(sizeof(*fpid), GFP_KERNEL); |
3679 | if (!fpid) | |
3680 | goto out_put; | |
df4fc315 | 3681 | |
756d17ee | 3682 | list_add(&fpid->list, &ftrace_pids); |
3683 | fpid->pid = pid; | |
0ef8cde5 | 3684 | |
756d17ee | 3685 | set_ftrace_pid_task(pid); |
978f3a45 | 3686 | |
756d17ee | 3687 | ftrace_update_pid_func(); |
3688 | ftrace_startup_enable(0); | |
3689 | ||
3690 | mutex_unlock(&ftrace_lock); | |
3691 | return 0; | |
3692 | ||
3693 | out_put: | |
3694 | if (pid != ftrace_swapper_pid) | |
3695 | put_pid(pid); | |
978f3a45 | 3696 | |
756d17ee | 3697 | out: |
3698 | mutex_unlock(&ftrace_lock); | |
3699 | return ret; | |
3700 | } | |
3701 | ||
3702 | static void ftrace_pid_reset(void) | |
3703 | { | |
3704 | struct ftrace_pid *fpid, *safe; | |
978f3a45 | 3705 | |
756d17ee | 3706 | mutex_lock(&ftrace_lock); |
3707 | list_for_each_entry_safe(fpid, safe, &ftrace_pids, list) { | |
3708 | struct pid *pid = fpid->pid; | |
3709 | ||
3710 | clear_ftrace_pid_task(pid); | |
3711 | ||
3712 | list_del(&fpid->list); | |
3713 | kfree(fpid); | |
df4fc315 SR |
3714 | } |
3715 | ||
df4fc315 SR |
3716 | ftrace_update_pid_func(); |
3717 | ftrace_startup_enable(0); | |
3718 | ||
e6ea44e9 | 3719 | mutex_unlock(&ftrace_lock); |
756d17ee | 3720 | } |
df4fc315 | 3721 | |
756d17ee | 3722 | static void *fpid_start(struct seq_file *m, loff_t *pos) |
3723 | { | |
3724 | mutex_lock(&ftrace_lock); | |
3725 | ||
3726 | if (list_empty(&ftrace_pids) && (!*pos)) | |
3727 | return (void *) 1; | |
3728 | ||
3729 | return seq_list_start(&ftrace_pids, *pos); | |
3730 | } | |
3731 | ||
3732 | static void *fpid_next(struct seq_file *m, void *v, loff_t *pos) | |
3733 | { | |
3734 | if (v == (void *)1) | |
3735 | return NULL; | |
3736 | ||
3737 | return seq_list_next(v, &ftrace_pids, pos); | |
3738 | } | |
3739 | ||
3740 | static void fpid_stop(struct seq_file *m, void *p) | |
3741 | { | |
3742 | mutex_unlock(&ftrace_lock); | |
3743 | } | |
3744 | ||
3745 | static int fpid_show(struct seq_file *m, void *v) | |
3746 | { | |
3747 | const struct ftrace_pid *fpid = list_entry(v, struct ftrace_pid, list); | |
3748 | ||
3749 | if (v == (void *)1) { | |
3750 | seq_printf(m, "no pid\n"); | |
3751 | return 0; | |
3752 | } | |
3753 | ||
3754 | if (fpid->pid == ftrace_swapper_pid) | |
3755 | seq_printf(m, "swapper tasks\n"); | |
3756 | else | |
3757 | seq_printf(m, "%u\n", pid_vnr(fpid->pid)); | |
3758 | ||
3759 | return 0; | |
3760 | } | |
3761 | ||
3762 | static const struct seq_operations ftrace_pid_sops = { | |
3763 | .start = fpid_start, | |
3764 | .next = fpid_next, | |
3765 | .stop = fpid_stop, | |
3766 | .show = fpid_show, | |
3767 | }; | |
3768 | ||
3769 | static int | |
3770 | ftrace_pid_open(struct inode *inode, struct file *file) | |
3771 | { | |
3772 | int ret = 0; | |
3773 | ||
3774 | if ((file->f_mode & FMODE_WRITE) && | |
3775 | (file->f_flags & O_TRUNC)) | |
3776 | ftrace_pid_reset(); | |
3777 | ||
3778 | if (file->f_mode & FMODE_READ) | |
3779 | ret = seq_open(file, &ftrace_pid_sops); | |
3780 | ||
3781 | return ret; | |
3782 | } | |
3783 | ||
df4fc315 SR |
3784 | static ssize_t |
3785 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
3786 | size_t cnt, loff_t *ppos) | |
3787 | { | |
457dc928 | 3788 | char buf[64], *tmp; |
df4fc315 SR |
3789 | long val; |
3790 | int ret; | |
3791 | ||
3792 | if (cnt >= sizeof(buf)) | |
3793 | return -EINVAL; | |
3794 | ||
3795 | if (copy_from_user(&buf, ubuf, cnt)) | |
3796 | return -EFAULT; | |
3797 | ||
3798 | buf[cnt] = 0; | |
3799 | ||
756d17ee | 3800 | /* |
3801 | * Allow "echo > set_ftrace_pid" or "echo -n '' > set_ftrace_pid" | |
3802 | * to clean the filter quietly. | |
3803 | */ | |
457dc928 IM |
3804 | tmp = strstrip(buf); |
3805 | if (strlen(tmp) == 0) | |
756d17ee | 3806 | return 1; |
3807 | ||
457dc928 | 3808 | ret = strict_strtol(tmp, 10, &val); |
df4fc315 SR |
3809 | if (ret < 0) |
3810 | return ret; | |
3811 | ||
756d17ee | 3812 | ret = ftrace_pid_add(val); |
df4fc315 | 3813 | |
756d17ee | 3814 | return ret ? ret : cnt; |
3815 | } | |
df4fc315 | 3816 | |
756d17ee | 3817 | static int |
3818 | ftrace_pid_release(struct inode *inode, struct file *file) | |
3819 | { | |
3820 | if (file->f_mode & FMODE_READ) | |
3821 | seq_release(inode, file); | |
df4fc315 | 3822 | |
756d17ee | 3823 | return 0; |
df4fc315 SR |
3824 | } |
3825 | ||
5e2336a0 | 3826 | static const struct file_operations ftrace_pid_fops = { |
756d17ee | 3827 | .open = ftrace_pid_open, |
3828 | .write = ftrace_pid_write, | |
3829 | .read = seq_read, | |
3830 | .llseek = seq_lseek, | |
3831 | .release = ftrace_pid_release, | |
df4fc315 SR |
3832 | }; |
3833 | ||
3834 | static __init int ftrace_init_debugfs(void) | |
3835 | { | |
3836 | struct dentry *d_tracer; | |
df4fc315 SR |
3837 | |
3838 | d_tracer = tracing_init_dentry(); | |
3839 | if (!d_tracer) | |
3840 | return 0; | |
3841 | ||
3842 | ftrace_init_dyn_debugfs(d_tracer); | |
3843 | ||
5452af66 FW |
3844 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
3845 | NULL, &ftrace_pid_fops); | |
493762fc SR |
3846 | |
3847 | ftrace_profile_debugfs(d_tracer); | |
3848 | ||
df4fc315 SR |
3849 | return 0; |
3850 | } | |
df4fc315 SR |
3851 | fs_initcall(ftrace_init_debugfs); |
3852 | ||
a2bb6a3d | 3853 | /** |
81adbdc0 | 3854 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
3855 | * |
3856 | * This function should be used by panic code. It stops ftrace | |
3857 | * but in a not so nice way. If you need to simply kill ftrace | |
3858 | * from a non-atomic section, use ftrace_kill. | |
3859 | */ | |
81adbdc0 | 3860 | void ftrace_kill(void) |
a2bb6a3d SR |
3861 | { |
3862 | ftrace_disabled = 1; | |
3863 | ftrace_enabled = 0; | |
a2bb6a3d SR |
3864 | clear_ftrace_function(); |
3865 | } | |
3866 | ||
e0a413f6 SR |
3867 | /** |
3868 | * Test if ftrace is dead or not. | |
3869 | */ | |
3870 | int ftrace_is_dead(void) | |
3871 | { | |
3872 | return ftrace_disabled; | |
3873 | } | |
3874 | ||
16444a8a | 3875 | /** |
3d083395 SR |
3876 | * register_ftrace_function - register a function for profiling |
3877 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 3878 | * |
3d083395 SR |
3879 | * Register a function to be called by all functions in the |
3880 | * kernel. | |
3881 | * | |
3882 | * Note: @ops->func and all the functions it calls must be labeled | |
3883 | * with "notrace", otherwise it will go into a | |
3884 | * recursive loop. | |
16444a8a | 3885 | */ |
3d083395 | 3886 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 3887 | { |
45a4a237 | 3888 | int ret = -1; |
4eebcc81 | 3889 | |
e6ea44e9 | 3890 | mutex_lock(&ftrace_lock); |
e7d3737e | 3891 | |
45a4a237 SR |
3892 | if (unlikely(ftrace_disabled)) |
3893 | goto out_unlock; | |
3894 | ||
b0fc494f | 3895 | ret = __register_ftrace_function(ops); |
b848914c | 3896 | if (!ret) |
a1cd6173 | 3897 | ret = ftrace_startup(ops, 0); |
b848914c | 3898 | |
b0fc494f | 3899 | |
45a4a237 | 3900 | out_unlock: |
e6ea44e9 | 3901 | mutex_unlock(&ftrace_lock); |
b0fc494f | 3902 | return ret; |
3d083395 | 3903 | } |
cdbe61bf | 3904 | EXPORT_SYMBOL_GPL(register_ftrace_function); |
3d083395 SR |
3905 | |
3906 | /** | |
32632920 | 3907 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
3908 | * @ops - ops structure that holds the function to unregister |
3909 | * | |
3910 | * Unregister a function that was added to be called by ftrace profiling. | |
3911 | */ | |
3912 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
3913 | { | |
3914 | int ret; | |
3915 | ||
e6ea44e9 | 3916 | mutex_lock(&ftrace_lock); |
3d083395 | 3917 | ret = __unregister_ftrace_function(ops); |
b848914c SR |
3918 | if (!ret) |
3919 | ftrace_shutdown(ops, 0); | |
e6ea44e9 | 3920 | mutex_unlock(&ftrace_lock); |
b0fc494f SR |
3921 | |
3922 | return ret; | |
3923 | } | |
cdbe61bf | 3924 | EXPORT_SYMBOL_GPL(unregister_ftrace_function); |
b0fc494f | 3925 | |
e309b41d | 3926 | int |
b0fc494f | 3927 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
8d65af78 | 3928 | void __user *buffer, size_t *lenp, |
b0fc494f SR |
3929 | loff_t *ppos) |
3930 | { | |
45a4a237 | 3931 | int ret = -ENODEV; |
4eebcc81 | 3932 | |
e6ea44e9 | 3933 | mutex_lock(&ftrace_lock); |
b0fc494f | 3934 | |
45a4a237 SR |
3935 | if (unlikely(ftrace_disabled)) |
3936 | goto out; | |
3937 | ||
3938 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
b0fc494f | 3939 | |
a32c7765 | 3940 | if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) |
b0fc494f SR |
3941 | goto out; |
3942 | ||
a32c7765 | 3943 | last_ftrace_enabled = !!ftrace_enabled; |
b0fc494f SR |
3944 | |
3945 | if (ftrace_enabled) { | |
3946 | ||
3947 | ftrace_startup_sysctl(); | |
3948 | ||
3949 | /* we are starting ftrace again */ | |
b848914c SR |
3950 | if (ftrace_ops_list != &ftrace_list_end) { |
3951 | if (ftrace_ops_list->next == &ftrace_list_end) | |
3952 | ftrace_trace_function = ftrace_ops_list->func; | |
b0fc494f | 3953 | else |
b848914c | 3954 | ftrace_trace_function = ftrace_ops_list_func; |
b0fc494f SR |
3955 | } |
3956 | ||
3957 | } else { | |
3958 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
3959 | ftrace_trace_function = ftrace_stub; | |
3960 | ||
3961 | ftrace_shutdown_sysctl(); | |
3962 | } | |
3963 | ||
3964 | out: | |
e6ea44e9 | 3965 | mutex_unlock(&ftrace_lock); |
3d083395 | 3966 | return ret; |
16444a8a | 3967 | } |
f17845e5 | 3968 | |
fb52607a | 3969 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 3970 | |
597af815 | 3971 | static int ftrace_graph_active; |
4a2b8dda | 3972 | static struct notifier_block ftrace_suspend_notifier; |
e7d3737e | 3973 | |
e49dc19c SR |
3974 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
3975 | { | |
3976 | return 0; | |
3977 | } | |
3978 | ||
287b6e68 FW |
3979 | /* The callbacks that hook a function */ |
3980 | trace_func_graph_ret_t ftrace_graph_return = | |
3981 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 3982 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
3983 | |
3984 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
3985 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
3986 | { | |
3987 | int i; | |
3988 | int ret = 0; | |
3989 | unsigned long flags; | |
3990 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; | |
3991 | struct task_struct *g, *t; | |
3992 | ||
3993 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
3994 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
3995 | * sizeof(struct ftrace_ret_stack), | |
3996 | GFP_KERNEL); | |
3997 | if (!ret_stack_list[i]) { | |
3998 | start = 0; | |
3999 | end = i; | |
4000 | ret = -ENOMEM; | |
4001 | goto free; | |
4002 | } | |
4003 | } | |
4004 | ||
4005 | read_lock_irqsave(&tasklist_lock, flags); | |
4006 | do_each_thread(g, t) { | |
4007 | if (start == end) { | |
4008 | ret = -EAGAIN; | |
4009 | goto unlock; | |
4010 | } | |
4011 | ||
4012 | if (t->ret_stack == NULL) { | |
380c4b14 | 4013 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 | 4014 | atomic_set(&t->trace_overrun, 0); |
26c01624 SR |
4015 | t->curr_ret_stack = -1; |
4016 | /* Make sure the tasks see the -1 first: */ | |
4017 | smp_wmb(); | |
4018 | t->ret_stack = ret_stack_list[start++]; | |
f201ae23 FW |
4019 | } |
4020 | } while_each_thread(g, t); | |
4021 | ||
4022 | unlock: | |
4023 | read_unlock_irqrestore(&tasklist_lock, flags); | |
4024 | free: | |
4025 | for (i = start; i < end; i++) | |
4026 | kfree(ret_stack_list[i]); | |
4027 | return ret; | |
4028 | } | |
4029 | ||
8aef2d28 | 4030 | static void |
38516ab5 SR |
4031 | ftrace_graph_probe_sched_switch(void *ignore, |
4032 | struct task_struct *prev, struct task_struct *next) | |
8aef2d28 SR |
4033 | { |
4034 | unsigned long long timestamp; | |
4035 | int index; | |
4036 | ||
be6f164a SR |
4037 | /* |
4038 | * Does the user want to count the time a function was asleep. | |
4039 | * If so, do not update the time stamps. | |
4040 | */ | |
4041 | if (trace_flags & TRACE_ITER_SLEEP_TIME) | |
4042 | return; | |
4043 | ||
8aef2d28 SR |
4044 | timestamp = trace_clock_local(); |
4045 | ||
4046 | prev->ftrace_timestamp = timestamp; | |
4047 | ||
4048 | /* only process tasks that we timestamped */ | |
4049 | if (!next->ftrace_timestamp) | |
4050 | return; | |
4051 | ||
4052 | /* | |
4053 | * Update all the counters in next to make up for the | |
4054 | * time next was sleeping. | |
4055 | */ | |
4056 | timestamp -= next->ftrace_timestamp; | |
4057 | ||
4058 | for (index = next->curr_ret_stack; index >= 0; index--) | |
4059 | next->ret_stack[index].calltime += timestamp; | |
4060 | } | |
4061 | ||
f201ae23 | 4062 | /* Allocate a return stack for each task */ |
fb52607a | 4063 | static int start_graph_tracing(void) |
f201ae23 FW |
4064 | { |
4065 | struct ftrace_ret_stack **ret_stack_list; | |
5b058bcd | 4066 | int ret, cpu; |
f201ae23 FW |
4067 | |
4068 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
4069 | sizeof(struct ftrace_ret_stack *), | |
4070 | GFP_KERNEL); | |
4071 | ||
4072 | if (!ret_stack_list) | |
4073 | return -ENOMEM; | |
4074 | ||
5b058bcd | 4075 | /* The cpu_boot init_task->ret_stack will never be freed */ |
179c498a SR |
4076 | for_each_online_cpu(cpu) { |
4077 | if (!idle_task(cpu)->ret_stack) | |
868baf07 | 4078 | ftrace_graph_init_idle_task(idle_task(cpu), cpu); |
179c498a | 4079 | } |
5b058bcd | 4080 | |
f201ae23 FW |
4081 | do { |
4082 | ret = alloc_retstack_tasklist(ret_stack_list); | |
4083 | } while (ret == -EAGAIN); | |
4084 | ||
8aef2d28 | 4085 | if (!ret) { |
38516ab5 | 4086 | ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
8aef2d28 SR |
4087 | if (ret) |
4088 | pr_info("ftrace_graph: Couldn't activate tracepoint" | |
4089 | " probe to kernel_sched_switch\n"); | |
4090 | } | |
4091 | ||
f201ae23 FW |
4092 | kfree(ret_stack_list); |
4093 | return ret; | |
4094 | } | |
4095 | ||
4a2b8dda FW |
4096 | /* |
4097 | * Hibernation protection. | |
4098 | * The state of the current task is too much unstable during | |
4099 | * suspend/restore to disk. We want to protect against that. | |
4100 | */ | |
4101 | static int | |
4102 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, | |
4103 | void *unused) | |
4104 | { | |
4105 | switch (state) { | |
4106 | case PM_HIBERNATION_PREPARE: | |
4107 | pause_graph_tracing(); | |
4108 | break; | |
4109 | ||
4110 | case PM_POST_HIBERNATION: | |
4111 | unpause_graph_tracing(); | |
4112 | break; | |
4113 | } | |
4114 | return NOTIFY_DONE; | |
4115 | } | |
4116 | ||
287b6e68 FW |
4117 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
4118 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 4119 | { |
e7d3737e FW |
4120 | int ret = 0; |
4121 | ||
e6ea44e9 | 4122 | mutex_lock(&ftrace_lock); |
e7d3737e | 4123 | |
05ce5818 | 4124 | /* we currently allow only one tracer registered at a time */ |
597af815 | 4125 | if (ftrace_graph_active) { |
05ce5818 SR |
4126 | ret = -EBUSY; |
4127 | goto out; | |
4128 | } | |
4129 | ||
4a2b8dda FW |
4130 | ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call; |
4131 | register_pm_notifier(&ftrace_suspend_notifier); | |
4132 | ||
597af815 | 4133 | ftrace_graph_active++; |
fb52607a | 4134 | ret = start_graph_tracing(); |
f201ae23 | 4135 | if (ret) { |
597af815 | 4136 | ftrace_graph_active--; |
f201ae23 FW |
4137 | goto out; |
4138 | } | |
e53a6319 | 4139 | |
287b6e68 FW |
4140 | ftrace_graph_return = retfunc; |
4141 | ftrace_graph_entry = entryfunc; | |
e53a6319 | 4142 | |
a1cd6173 | 4143 | ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET); |
e7d3737e FW |
4144 | |
4145 | out: | |
e6ea44e9 | 4146 | mutex_unlock(&ftrace_lock); |
e7d3737e | 4147 | return ret; |
15e6cb36 FW |
4148 | } |
4149 | ||
fb52607a | 4150 | void unregister_ftrace_graph(void) |
15e6cb36 | 4151 | { |
e6ea44e9 | 4152 | mutex_lock(&ftrace_lock); |
e7d3737e | 4153 | |
597af815 | 4154 | if (unlikely(!ftrace_graph_active)) |
2aad1b76 SR |
4155 | goto out; |
4156 | ||
597af815 | 4157 | ftrace_graph_active--; |
287b6e68 | 4158 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; |
e49dc19c | 4159 | ftrace_graph_entry = ftrace_graph_entry_stub; |
bd69c30b | 4160 | ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET); |
4a2b8dda | 4161 | unregister_pm_notifier(&ftrace_suspend_notifier); |
38516ab5 | 4162 | unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
e7d3737e | 4163 | |
2aad1b76 | 4164 | out: |
e6ea44e9 | 4165 | mutex_unlock(&ftrace_lock); |
15e6cb36 | 4166 | } |
f201ae23 | 4167 | |
868baf07 SR |
4168 | static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack); |
4169 | ||
4170 | static void | |
4171 | graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack) | |
4172 | { | |
4173 | atomic_set(&t->tracing_graph_pause, 0); | |
4174 | atomic_set(&t->trace_overrun, 0); | |
4175 | t->ftrace_timestamp = 0; | |
25985edc | 4176 | /* make curr_ret_stack visible before we add the ret_stack */ |
868baf07 SR |
4177 | smp_wmb(); |
4178 | t->ret_stack = ret_stack; | |
4179 | } | |
4180 | ||
4181 | /* | |
4182 | * Allocate a return stack for the idle task. May be the first | |
4183 | * time through, or it may be done by CPU hotplug online. | |
4184 | */ | |
4185 | void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) | |
4186 | { | |
4187 | t->curr_ret_stack = -1; | |
4188 | /* | |
4189 | * The idle task has no parent, it either has its own | |
4190 | * stack or no stack at all. | |
4191 | */ | |
4192 | if (t->ret_stack) | |
4193 | WARN_ON(t->ret_stack != per_cpu(idle_ret_stack, cpu)); | |
4194 | ||
4195 | if (ftrace_graph_active) { | |
4196 | struct ftrace_ret_stack *ret_stack; | |
4197 | ||
4198 | ret_stack = per_cpu(idle_ret_stack, cpu); | |
4199 | if (!ret_stack) { | |
4200 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
4201 | * sizeof(struct ftrace_ret_stack), | |
4202 | GFP_KERNEL); | |
4203 | if (!ret_stack) | |
4204 | return; | |
4205 | per_cpu(idle_ret_stack, cpu) = ret_stack; | |
4206 | } | |
4207 | graph_init_task(t, ret_stack); | |
4208 | } | |
4209 | } | |
4210 | ||
f201ae23 | 4211 | /* Allocate a return stack for newly created task */ |
fb52607a | 4212 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 4213 | { |
84047e36 SR |
4214 | /* Make sure we do not use the parent ret_stack */ |
4215 | t->ret_stack = NULL; | |
ea14eb71 | 4216 | t->curr_ret_stack = -1; |
84047e36 | 4217 | |
597af815 | 4218 | if (ftrace_graph_active) { |
82310a32 SR |
4219 | struct ftrace_ret_stack *ret_stack; |
4220 | ||
4221 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
f201ae23 FW |
4222 | * sizeof(struct ftrace_ret_stack), |
4223 | GFP_KERNEL); | |
82310a32 | 4224 | if (!ret_stack) |
f201ae23 | 4225 | return; |
868baf07 | 4226 | graph_init_task(t, ret_stack); |
84047e36 | 4227 | } |
f201ae23 FW |
4228 | } |
4229 | ||
fb52607a | 4230 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 4231 | { |
eae849ca FW |
4232 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
4233 | ||
f201ae23 | 4234 | t->ret_stack = NULL; |
eae849ca FW |
4235 | /* NULL must become visible to IRQs before we free it: */ |
4236 | barrier(); | |
4237 | ||
4238 | kfree(ret_stack); | |
f201ae23 | 4239 | } |
14a866c5 SR |
4240 | |
4241 | void ftrace_graph_stop(void) | |
4242 | { | |
4243 | ftrace_stop(); | |
4244 | } | |
15e6cb36 | 4245 | #endif |