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