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