]>
Commit | Line | Data |
---|---|---|
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 | ||
90 | static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end; | |
91 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; | |
60a7ecf4 | 92 | ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub; |
df4fc315 | 93 | ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub; |
16444a8a | 94 | |
3f379b03 PM |
95 | /* |
96 | * Traverse the ftrace_list, invoking all entries. The reason that we | |
97 | * can use rcu_dereference_raw() is that elements removed from this list | |
98 | * are simply leaked, so there is no need to interact with a grace-period | |
99 | * mechanism. The rcu_dereference_raw() calls are needed to handle | |
100 | * concurrent insertions into the ftrace_list. | |
101 | * | |
102 | * Silly Alpha and silly pointer-speculation compiler optimizations! | |
103 | */ | |
f2252935 | 104 | static void ftrace_list_func(unsigned long ip, unsigned long parent_ip) |
16444a8a | 105 | { |
3f379b03 | 106 | struct ftrace_ops *op = rcu_dereference_raw(ftrace_list); /*see above*/ |
16444a8a ACM |
107 | |
108 | while (op != &ftrace_list_end) { | |
16444a8a | 109 | op->func(ip, parent_ip); |
3f379b03 | 110 | op = rcu_dereference_raw(op->next); /*see above*/ |
16444a8a ACM |
111 | }; |
112 | } | |
113 | ||
df4fc315 SR |
114 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip) |
115 | { | |
0ef8cde5 | 116 | if (!test_tsk_trace_trace(current)) |
df4fc315 SR |
117 | return; |
118 | ||
119 | ftrace_pid_function(ip, parent_ip); | |
120 | } | |
121 | ||
122 | static void set_ftrace_pid_function(ftrace_func_t func) | |
123 | { | |
124 | /* do not set ftrace_pid_function to itself! */ | |
125 | if (func != ftrace_pid_func) | |
126 | ftrace_pid_function = func; | |
127 | } | |
128 | ||
16444a8a | 129 | /** |
3d083395 | 130 | * clear_ftrace_function - reset the ftrace function |
16444a8a | 131 | * |
3d083395 SR |
132 | * This NULLs the ftrace function and in essence stops |
133 | * tracing. There may be lag | |
16444a8a | 134 | */ |
3d083395 | 135 | void clear_ftrace_function(void) |
16444a8a | 136 | { |
3d083395 | 137 | ftrace_trace_function = ftrace_stub; |
60a7ecf4 | 138 | __ftrace_trace_function = ftrace_stub; |
df4fc315 | 139 | ftrace_pid_function = ftrace_stub; |
3d083395 SR |
140 | } |
141 | ||
60a7ecf4 SR |
142 | #ifndef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
143 | /* | |
144 | * For those archs that do not test ftrace_trace_stop in their | |
145 | * mcount call site, we need to do it from C. | |
146 | */ | |
147 | static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip) | |
148 | { | |
149 | if (function_trace_stop) | |
150 | return; | |
151 | ||
152 | __ftrace_trace_function(ip, parent_ip); | |
153 | } | |
154 | #endif | |
155 | ||
491d0dcf SR |
156 | static void update_ftrace_function(void) |
157 | { | |
158 | ftrace_func_t func; | |
159 | ||
160 | /* | |
161 | * If there's only one function registered, then call that | |
162 | * function directly. Otherwise, we need to iterate over the | |
163 | * registered callers. | |
164 | */ | |
165 | if (ftrace_list == &ftrace_list_end || | |
166 | ftrace_list->next == &ftrace_list_end) | |
167 | func = ftrace_list->func; | |
168 | else | |
169 | func = ftrace_list_func; | |
170 | ||
171 | /* If we filter on pids, update to use the pid function */ | |
172 | if (!list_empty(&ftrace_pids)) { | |
173 | set_ftrace_pid_function(func); | |
174 | func = ftrace_pid_func; | |
175 | } | |
176 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST | |
177 | ftrace_trace_function = func; | |
178 | #else | |
179 | __ftrace_trace_function = func; | |
180 | ftrace_trace_function = ftrace_test_stop_func; | |
181 | #endif | |
182 | } | |
183 | ||
e309b41d | 184 | static int __register_ftrace_function(struct ftrace_ops *ops) |
3d083395 | 185 | { |
16444a8a ACM |
186 | ops->next = ftrace_list; |
187 | /* | |
188 | * We are entering ops into the ftrace_list but another | |
189 | * CPU might be walking that list. We need to make sure | |
190 | * the ops->next pointer is valid before another CPU sees | |
191 | * the ops pointer included into the ftrace_list. | |
192 | */ | |
3f379b03 | 193 | rcu_assign_pointer(ftrace_list, ops); |
3d083395 | 194 | |
491d0dcf SR |
195 | if (ftrace_enabled) |
196 | update_ftrace_function(); | |
3d083395 | 197 | |
16444a8a ACM |
198 | return 0; |
199 | } | |
200 | ||
e309b41d | 201 | static int __unregister_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 202 | { |
16444a8a | 203 | struct ftrace_ops **p; |
16444a8a ACM |
204 | |
205 | /* | |
3d083395 SR |
206 | * If we are removing the last function, then simply point |
207 | * to the ftrace_stub. | |
16444a8a ACM |
208 | */ |
209 | if (ftrace_list == ops && ops->next == &ftrace_list_end) { | |
210 | ftrace_trace_function = ftrace_stub; | |
211 | ftrace_list = &ftrace_list_end; | |
e6ea44e9 | 212 | return 0; |
16444a8a ACM |
213 | } |
214 | ||
215 | for (p = &ftrace_list; *p != &ftrace_list_end; p = &(*p)->next) | |
216 | if (*p == ops) | |
217 | break; | |
218 | ||
e6ea44e9 SR |
219 | if (*p != ops) |
220 | return -1; | |
16444a8a ACM |
221 | |
222 | *p = (*p)->next; | |
223 | ||
491d0dcf SR |
224 | if (ftrace_enabled) |
225 | update_ftrace_function(); | |
16444a8a | 226 | |
e6ea44e9 | 227 | return 0; |
3d083395 SR |
228 | } |
229 | ||
df4fc315 SR |
230 | static void ftrace_update_pid_func(void) |
231 | { | |
491d0dcf | 232 | /* Only do something if we are tracing something */ |
df4fc315 | 233 | if (ftrace_trace_function == ftrace_stub) |
10dd3ebe | 234 | return; |
df4fc315 | 235 | |
491d0dcf | 236 | update_ftrace_function(); |
df4fc315 SR |
237 | } |
238 | ||
493762fc SR |
239 | #ifdef CONFIG_FUNCTION_PROFILER |
240 | struct ftrace_profile { | |
241 | struct hlist_node node; | |
242 | unsigned long ip; | |
243 | unsigned long counter; | |
0706f1c4 SR |
244 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
245 | unsigned long long time; | |
e330b3bc | 246 | unsigned long long time_squared; |
0706f1c4 | 247 | #endif |
8fc0c701 SR |
248 | }; |
249 | ||
493762fc SR |
250 | struct ftrace_profile_page { |
251 | struct ftrace_profile_page *next; | |
252 | unsigned long index; | |
253 | struct ftrace_profile records[]; | |
d61f82d0 SR |
254 | }; |
255 | ||
cafb168a SR |
256 | struct ftrace_profile_stat { |
257 | atomic_t disabled; | |
258 | struct hlist_head *hash; | |
259 | struct ftrace_profile_page *pages; | |
260 | struct ftrace_profile_page *start; | |
261 | struct tracer_stat stat; | |
262 | }; | |
263 | ||
493762fc SR |
264 | #define PROFILE_RECORDS_SIZE \ |
265 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | |
5072c59f | 266 | |
493762fc SR |
267 | #define PROFILES_PER_PAGE \ |
268 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | |
3d083395 | 269 | |
fb9fb015 SR |
270 | static int ftrace_profile_bits __read_mostly; |
271 | static int ftrace_profile_enabled __read_mostly; | |
272 | ||
273 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ | |
bac429f0 SR |
274 | static DEFINE_MUTEX(ftrace_profile_lock); |
275 | ||
cafb168a | 276 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); |
493762fc SR |
277 | |
278 | #define FTRACE_PROFILE_HASH_SIZE 1024 /* must be power of 2 */ | |
279 | ||
bac429f0 SR |
280 | static void * |
281 | function_stat_next(void *v, int idx) | |
282 | { | |
493762fc SR |
283 | struct ftrace_profile *rec = v; |
284 | struct ftrace_profile_page *pg; | |
bac429f0 | 285 | |
493762fc | 286 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
bac429f0 SR |
287 | |
288 | again: | |
0296e425 LZ |
289 | if (idx != 0) |
290 | rec++; | |
291 | ||
bac429f0 SR |
292 | if ((void *)rec >= (void *)&pg->records[pg->index]) { |
293 | pg = pg->next; | |
294 | if (!pg) | |
295 | return NULL; | |
296 | rec = &pg->records[0]; | |
493762fc SR |
297 | if (!rec->counter) |
298 | goto again; | |
bac429f0 SR |
299 | } |
300 | ||
bac429f0 SR |
301 | return rec; |
302 | } | |
303 | ||
304 | static void *function_stat_start(struct tracer_stat *trace) | |
305 | { | |
cafb168a SR |
306 | struct ftrace_profile_stat *stat = |
307 | container_of(trace, struct ftrace_profile_stat, stat); | |
308 | ||
309 | if (!stat || !stat->start) | |
310 | return NULL; | |
311 | ||
312 | return function_stat_next(&stat->start->records[0], 0); | |
bac429f0 SR |
313 | } |
314 | ||
0706f1c4 SR |
315 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
316 | /* function graph compares on total time */ | |
317 | static int function_stat_cmp(void *p1, void *p2) | |
318 | { | |
319 | struct ftrace_profile *a = p1; | |
320 | struct ftrace_profile *b = p2; | |
321 | ||
322 | if (a->time < b->time) | |
323 | return -1; | |
324 | if (a->time > b->time) | |
325 | return 1; | |
326 | else | |
327 | return 0; | |
328 | } | |
329 | #else | |
330 | /* not function graph compares against hits */ | |
bac429f0 SR |
331 | static int function_stat_cmp(void *p1, void *p2) |
332 | { | |
493762fc SR |
333 | struct ftrace_profile *a = p1; |
334 | struct ftrace_profile *b = p2; | |
bac429f0 SR |
335 | |
336 | if (a->counter < b->counter) | |
337 | return -1; | |
338 | if (a->counter > b->counter) | |
339 | return 1; | |
340 | else | |
341 | return 0; | |
342 | } | |
0706f1c4 | 343 | #endif |
bac429f0 SR |
344 | |
345 | static int function_stat_headers(struct seq_file *m) | |
346 | { | |
0706f1c4 | 347 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b | 348 | seq_printf(m, " Function " |
e330b3bc | 349 | "Hit Time Avg s^2\n" |
34886c8b | 350 | " -------- " |
e330b3bc | 351 | "--- ---- --- ---\n"); |
0706f1c4 | 352 | #else |
bac429f0 SR |
353 | seq_printf(m, " Function Hit\n" |
354 | " -------- ---\n"); | |
0706f1c4 | 355 | #endif |
bac429f0 SR |
356 | return 0; |
357 | } | |
358 | ||
359 | static int function_stat_show(struct seq_file *m, void *v) | |
360 | { | |
493762fc | 361 | struct ftrace_profile *rec = v; |
bac429f0 | 362 | char str[KSYM_SYMBOL_LEN]; |
3aaba20f | 363 | int ret = 0; |
0706f1c4 | 364 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b SR |
365 | static struct trace_seq s; |
366 | unsigned long long avg; | |
e330b3bc | 367 | unsigned long long stddev; |
0706f1c4 | 368 | #endif |
3aaba20f LZ |
369 | mutex_lock(&ftrace_profile_lock); |
370 | ||
371 | /* we raced with function_profile_reset() */ | |
372 | if (unlikely(rec->counter == 0)) { | |
373 | ret = -EBUSY; | |
374 | goto out; | |
375 | } | |
bac429f0 SR |
376 | |
377 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
0706f1c4 SR |
378 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); |
379 | ||
380 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
381 | seq_printf(m, " "); | |
34886c8b SR |
382 | avg = rec->time; |
383 | do_div(avg, rec->counter); | |
384 | ||
e330b3bc CD |
385 | /* Sample standard deviation (s^2) */ |
386 | if (rec->counter <= 1) | |
387 | stddev = 0; | |
388 | else { | |
389 | stddev = rec->time_squared - rec->counter * avg * avg; | |
390 | /* | |
391 | * Divide only 1000 for ns^2 -> us^2 conversion. | |
392 | * trace_print_graph_duration will divide 1000 again. | |
393 | */ | |
394 | do_div(stddev, (rec->counter - 1) * 1000); | |
395 | } | |
396 | ||
34886c8b SR |
397 | trace_seq_init(&s); |
398 | trace_print_graph_duration(rec->time, &s); | |
399 | trace_seq_puts(&s, " "); | |
400 | trace_print_graph_duration(avg, &s); | |
e330b3bc CD |
401 | trace_seq_puts(&s, " "); |
402 | trace_print_graph_duration(stddev, &s); | |
0706f1c4 | 403 | trace_print_seq(m, &s); |
0706f1c4 SR |
404 | #endif |
405 | seq_putc(m, '\n'); | |
3aaba20f LZ |
406 | out: |
407 | mutex_unlock(&ftrace_profile_lock); | |
bac429f0 | 408 | |
3aaba20f | 409 | return ret; |
bac429f0 SR |
410 | } |
411 | ||
cafb168a | 412 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) |
bac429f0 | 413 | { |
493762fc | 414 | struct ftrace_profile_page *pg; |
bac429f0 | 415 | |
cafb168a | 416 | pg = stat->pages = stat->start; |
bac429f0 | 417 | |
493762fc SR |
418 | while (pg) { |
419 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | |
420 | pg->index = 0; | |
421 | pg = pg->next; | |
bac429f0 SR |
422 | } |
423 | ||
cafb168a | 424 | memset(stat->hash, 0, |
493762fc SR |
425 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); |
426 | } | |
bac429f0 | 427 | |
cafb168a | 428 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) |
493762fc SR |
429 | { |
430 | struct ftrace_profile_page *pg; | |
318e0a73 SR |
431 | int functions; |
432 | int pages; | |
493762fc | 433 | int i; |
bac429f0 | 434 | |
493762fc | 435 | /* If we already allocated, do nothing */ |
cafb168a | 436 | if (stat->pages) |
493762fc | 437 | return 0; |
bac429f0 | 438 | |
cafb168a SR |
439 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); |
440 | if (!stat->pages) | |
493762fc | 441 | return -ENOMEM; |
bac429f0 | 442 | |
318e0a73 SR |
443 | #ifdef CONFIG_DYNAMIC_FTRACE |
444 | functions = ftrace_update_tot_cnt; | |
445 | #else | |
446 | /* | |
447 | * We do not know the number of functions that exist because | |
448 | * dynamic tracing is what counts them. With past experience | |
449 | * we have around 20K functions. That should be more than enough. | |
450 | * It is highly unlikely we will execute every function in | |
451 | * the kernel. | |
452 | */ | |
453 | functions = 20000; | |
454 | #endif | |
455 | ||
cafb168a | 456 | pg = stat->start = stat->pages; |
bac429f0 | 457 | |
318e0a73 SR |
458 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); |
459 | ||
460 | for (i = 0; i < pages; i++) { | |
493762fc | 461 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
493762fc | 462 | if (!pg->next) |
318e0a73 | 463 | goto out_free; |
493762fc SR |
464 | pg = pg->next; |
465 | } | |
466 | ||
467 | return 0; | |
318e0a73 SR |
468 | |
469 | out_free: | |
470 | pg = stat->start; | |
471 | while (pg) { | |
472 | unsigned long tmp = (unsigned long)pg; | |
473 | ||
474 | pg = pg->next; | |
475 | free_page(tmp); | |
476 | } | |
477 | ||
478 | free_page((unsigned long)stat->pages); | |
479 | stat->pages = NULL; | |
480 | stat->start = NULL; | |
481 | ||
482 | return -ENOMEM; | |
bac429f0 SR |
483 | } |
484 | ||
cafb168a | 485 | static int ftrace_profile_init_cpu(int cpu) |
bac429f0 | 486 | { |
cafb168a | 487 | struct ftrace_profile_stat *stat; |
493762fc | 488 | int size; |
bac429f0 | 489 | |
cafb168a SR |
490 | stat = &per_cpu(ftrace_profile_stats, cpu); |
491 | ||
492 | if (stat->hash) { | |
493762fc | 493 | /* If the profile is already created, simply reset it */ |
cafb168a | 494 | ftrace_profile_reset(stat); |
493762fc SR |
495 | return 0; |
496 | } | |
bac429f0 | 497 | |
493762fc SR |
498 | /* |
499 | * We are profiling all functions, but usually only a few thousand | |
500 | * functions are hit. We'll make a hash of 1024 items. | |
501 | */ | |
502 | size = FTRACE_PROFILE_HASH_SIZE; | |
bac429f0 | 503 | |
cafb168a | 504 | stat->hash = kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL); |
493762fc | 505 | |
cafb168a | 506 | if (!stat->hash) |
493762fc SR |
507 | return -ENOMEM; |
508 | ||
cafb168a SR |
509 | if (!ftrace_profile_bits) { |
510 | size--; | |
493762fc | 511 | |
cafb168a SR |
512 | for (; size; size >>= 1) |
513 | ftrace_profile_bits++; | |
514 | } | |
493762fc | 515 | |
318e0a73 | 516 | /* Preallocate the function profiling pages */ |
cafb168a SR |
517 | if (ftrace_profile_pages_init(stat) < 0) { |
518 | kfree(stat->hash); | |
519 | stat->hash = NULL; | |
493762fc SR |
520 | return -ENOMEM; |
521 | } | |
522 | ||
523 | return 0; | |
bac429f0 SR |
524 | } |
525 | ||
cafb168a SR |
526 | static int ftrace_profile_init(void) |
527 | { | |
528 | int cpu; | |
529 | int ret = 0; | |
530 | ||
531 | for_each_online_cpu(cpu) { | |
532 | ret = ftrace_profile_init_cpu(cpu); | |
533 | if (ret) | |
534 | break; | |
535 | } | |
536 | ||
537 | return ret; | |
538 | } | |
539 | ||
493762fc | 540 | /* interrupts must be disabled */ |
cafb168a SR |
541 | static struct ftrace_profile * |
542 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) | |
bac429f0 | 543 | { |
493762fc | 544 | struct ftrace_profile *rec; |
bac429f0 SR |
545 | struct hlist_head *hhd; |
546 | struct hlist_node *n; | |
bac429f0 SR |
547 | unsigned long key; |
548 | ||
bac429f0 | 549 | key = hash_long(ip, ftrace_profile_bits); |
cafb168a | 550 | hhd = &stat->hash[key]; |
bac429f0 SR |
551 | |
552 | if (hlist_empty(hhd)) | |
553 | return NULL; | |
554 | ||
bac429f0 SR |
555 | hlist_for_each_entry_rcu(rec, n, hhd, node) { |
556 | if (rec->ip == ip) | |
493762fc SR |
557 | return rec; |
558 | } | |
559 | ||
560 | return NULL; | |
561 | } | |
562 | ||
cafb168a SR |
563 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, |
564 | struct ftrace_profile *rec) | |
493762fc SR |
565 | { |
566 | unsigned long key; | |
567 | ||
568 | key = hash_long(rec->ip, ftrace_profile_bits); | |
cafb168a | 569 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); |
493762fc SR |
570 | } |
571 | ||
318e0a73 SR |
572 | /* |
573 | * The memory is already allocated, this simply finds a new record to use. | |
574 | */ | |
493762fc | 575 | static struct ftrace_profile * |
318e0a73 | 576 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) |
493762fc SR |
577 | { |
578 | struct ftrace_profile *rec = NULL; | |
579 | ||
318e0a73 | 580 | /* prevent recursion (from NMIs) */ |
cafb168a | 581 | if (atomic_inc_return(&stat->disabled) != 1) |
493762fc SR |
582 | goto out; |
583 | ||
493762fc | 584 | /* |
318e0a73 SR |
585 | * Try to find the function again since an NMI |
586 | * could have added it | |
493762fc | 587 | */ |
cafb168a | 588 | rec = ftrace_find_profiled_func(stat, ip); |
493762fc | 589 | if (rec) |
cafb168a | 590 | goto out; |
493762fc | 591 | |
cafb168a SR |
592 | if (stat->pages->index == PROFILES_PER_PAGE) { |
593 | if (!stat->pages->next) | |
594 | goto out; | |
595 | stat->pages = stat->pages->next; | |
bac429f0 | 596 | } |
493762fc | 597 | |
cafb168a | 598 | rec = &stat->pages->records[stat->pages->index++]; |
493762fc | 599 | rec->ip = ip; |
cafb168a | 600 | ftrace_add_profile(stat, rec); |
493762fc | 601 | |
bac429f0 | 602 | out: |
cafb168a | 603 | atomic_dec(&stat->disabled); |
bac429f0 SR |
604 | |
605 | return rec; | |
606 | } | |
607 | ||
608 | static void | |
609 | function_profile_call(unsigned long ip, unsigned long parent_ip) | |
610 | { | |
cafb168a | 611 | struct ftrace_profile_stat *stat; |
493762fc | 612 | struct ftrace_profile *rec; |
bac429f0 SR |
613 | unsigned long flags; |
614 | ||
615 | if (!ftrace_profile_enabled) | |
616 | return; | |
617 | ||
618 | local_irq_save(flags); | |
cafb168a SR |
619 | |
620 | stat = &__get_cpu_var(ftrace_profile_stats); | |
0f6ce3de | 621 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
622 | goto out; |
623 | ||
624 | rec = ftrace_find_profiled_func(stat, ip); | |
493762fc | 625 | if (!rec) { |
318e0a73 | 626 | rec = ftrace_profile_alloc(stat, ip); |
493762fc SR |
627 | if (!rec) |
628 | goto out; | |
629 | } | |
bac429f0 SR |
630 | |
631 | rec->counter++; | |
632 | out: | |
633 | local_irq_restore(flags); | |
634 | } | |
635 | ||
0706f1c4 SR |
636 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
637 | static int profile_graph_entry(struct ftrace_graph_ent *trace) | |
638 | { | |
639 | function_profile_call(trace->func, 0); | |
640 | return 1; | |
641 | } | |
642 | ||
643 | static void profile_graph_return(struct ftrace_graph_ret *trace) | |
644 | { | |
cafb168a | 645 | struct ftrace_profile_stat *stat; |
a2a16d6a | 646 | unsigned long long calltime; |
0706f1c4 | 647 | struct ftrace_profile *rec; |
cafb168a | 648 | unsigned long flags; |
0706f1c4 SR |
649 | |
650 | local_irq_save(flags); | |
cafb168a | 651 | stat = &__get_cpu_var(ftrace_profile_stats); |
0f6ce3de | 652 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
653 | goto out; |
654 | ||
37e44bc5 SR |
655 | /* If the calltime was zero'd ignore it */ |
656 | if (!trace->calltime) | |
657 | goto out; | |
658 | ||
a2a16d6a SR |
659 | calltime = trace->rettime - trace->calltime; |
660 | ||
661 | if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) { | |
662 | int index; | |
663 | ||
664 | index = trace->depth; | |
665 | ||
666 | /* Append this call time to the parent time to subtract */ | |
667 | if (index) | |
668 | current->ret_stack[index - 1].subtime += calltime; | |
669 | ||
670 | if (current->ret_stack[index].subtime < calltime) | |
671 | calltime -= current->ret_stack[index].subtime; | |
672 | else | |
673 | calltime = 0; | |
674 | } | |
675 | ||
cafb168a | 676 | rec = ftrace_find_profiled_func(stat, trace->func); |
e330b3bc | 677 | if (rec) { |
a2a16d6a | 678 | rec->time += calltime; |
e330b3bc CD |
679 | rec->time_squared += calltime * calltime; |
680 | } | |
a2a16d6a | 681 | |
cafb168a | 682 | out: |
0706f1c4 SR |
683 | local_irq_restore(flags); |
684 | } | |
685 | ||
686 | static int register_ftrace_profiler(void) | |
687 | { | |
688 | return register_ftrace_graph(&profile_graph_return, | |
689 | &profile_graph_entry); | |
690 | } | |
691 | ||
692 | static void unregister_ftrace_profiler(void) | |
693 | { | |
694 | unregister_ftrace_graph(); | |
695 | } | |
696 | #else | |
bac429f0 SR |
697 | static struct ftrace_ops ftrace_profile_ops __read_mostly = |
698 | { | |
fb9fb015 | 699 | .func = function_profile_call, |
bac429f0 SR |
700 | }; |
701 | ||
0706f1c4 SR |
702 | static int register_ftrace_profiler(void) |
703 | { | |
704 | return register_ftrace_function(&ftrace_profile_ops); | |
705 | } | |
706 | ||
707 | static void unregister_ftrace_profiler(void) | |
708 | { | |
709 | unregister_ftrace_function(&ftrace_profile_ops); | |
710 | } | |
711 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
712 | ||
bac429f0 SR |
713 | static ssize_t |
714 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | |
715 | size_t cnt, loff_t *ppos) | |
716 | { | |
717 | unsigned long val; | |
fb9fb015 | 718 | char buf[64]; /* big enough to hold a number */ |
bac429f0 SR |
719 | int ret; |
720 | ||
bac429f0 SR |
721 | if (cnt >= sizeof(buf)) |
722 | return -EINVAL; | |
723 | ||
724 | if (copy_from_user(&buf, ubuf, cnt)) | |
725 | return -EFAULT; | |
726 | ||
727 | buf[cnt] = 0; | |
728 | ||
729 | ret = strict_strtoul(buf, 10, &val); | |
730 | if (ret < 0) | |
731 | return ret; | |
732 | ||
733 | val = !!val; | |
734 | ||
735 | mutex_lock(&ftrace_profile_lock); | |
736 | if (ftrace_profile_enabled ^ val) { | |
737 | if (val) { | |
493762fc SR |
738 | ret = ftrace_profile_init(); |
739 | if (ret < 0) { | |
740 | cnt = ret; | |
741 | goto out; | |
742 | } | |
743 | ||
0706f1c4 SR |
744 | ret = register_ftrace_profiler(); |
745 | if (ret < 0) { | |
746 | cnt = ret; | |
747 | goto out; | |
748 | } | |
bac429f0 SR |
749 | ftrace_profile_enabled = 1; |
750 | } else { | |
751 | ftrace_profile_enabled = 0; | |
0f6ce3de SR |
752 | /* |
753 | * unregister_ftrace_profiler calls stop_machine | |
754 | * so this acts like an synchronize_sched. | |
755 | */ | |
0706f1c4 | 756 | unregister_ftrace_profiler(); |
bac429f0 SR |
757 | } |
758 | } | |
493762fc | 759 | out: |
bac429f0 SR |
760 | mutex_unlock(&ftrace_profile_lock); |
761 | ||
cf8517cf | 762 | *ppos += cnt; |
bac429f0 SR |
763 | |
764 | return cnt; | |
765 | } | |
766 | ||
493762fc SR |
767 | static ssize_t |
768 | ftrace_profile_read(struct file *filp, char __user *ubuf, | |
769 | size_t cnt, loff_t *ppos) | |
770 | { | |
fb9fb015 | 771 | char buf[64]; /* big enough to hold a number */ |
493762fc SR |
772 | int r; |
773 | ||
774 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | |
775 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
776 | } | |
777 | ||
bac429f0 SR |
778 | static const struct file_operations ftrace_profile_fops = { |
779 | .open = tracing_open_generic, | |
780 | .read = ftrace_profile_read, | |
781 | .write = ftrace_profile_write, | |
6038f373 | 782 | .llseek = default_llseek, |
bac429f0 SR |
783 | }; |
784 | ||
cafb168a SR |
785 | /* used to initialize the real stat files */ |
786 | static struct tracer_stat function_stats __initdata = { | |
fb9fb015 SR |
787 | .name = "functions", |
788 | .stat_start = function_stat_start, | |
789 | .stat_next = function_stat_next, | |
790 | .stat_cmp = function_stat_cmp, | |
791 | .stat_headers = function_stat_headers, | |
792 | .stat_show = function_stat_show | |
cafb168a SR |
793 | }; |
794 | ||
6ab5d668 | 795 | static __init void ftrace_profile_debugfs(struct dentry *d_tracer) |
bac429f0 | 796 | { |
cafb168a | 797 | struct ftrace_profile_stat *stat; |
bac429f0 | 798 | struct dentry *entry; |
cafb168a | 799 | char *name; |
bac429f0 | 800 | int ret; |
cafb168a SR |
801 | int cpu; |
802 | ||
803 | for_each_possible_cpu(cpu) { | |
804 | stat = &per_cpu(ftrace_profile_stats, cpu); | |
805 | ||
806 | /* allocate enough for function name + cpu number */ | |
807 | name = kmalloc(32, GFP_KERNEL); | |
808 | if (!name) { | |
809 | /* | |
810 | * The files created are permanent, if something happens | |
811 | * we still do not free memory. | |
812 | */ | |
cafb168a SR |
813 | WARN(1, |
814 | "Could not allocate stat file for cpu %d\n", | |
815 | cpu); | |
816 | return; | |
817 | } | |
818 | stat->stat = function_stats; | |
819 | snprintf(name, 32, "function%d", cpu); | |
820 | stat->stat.name = name; | |
821 | ret = register_stat_tracer(&stat->stat); | |
822 | if (ret) { | |
823 | WARN(1, | |
824 | "Could not register function stat for cpu %d\n", | |
825 | cpu); | |
826 | kfree(name); | |
827 | return; | |
828 | } | |
bac429f0 SR |
829 | } |
830 | ||
831 | entry = debugfs_create_file("function_profile_enabled", 0644, | |
832 | d_tracer, NULL, &ftrace_profile_fops); | |
833 | if (!entry) | |
834 | pr_warning("Could not create debugfs " | |
835 | "'function_profile_enabled' entry\n"); | |
836 | } | |
837 | ||
bac429f0 | 838 | #else /* CONFIG_FUNCTION_PROFILER */ |
6ab5d668 | 839 | static __init void ftrace_profile_debugfs(struct dentry *d_tracer) |
bac429f0 SR |
840 | { |
841 | } | |
bac429f0 SR |
842 | #endif /* CONFIG_FUNCTION_PROFILER */ |
843 | ||
493762fc SR |
844 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; |
845 | ||
846 | #ifdef CONFIG_DYNAMIC_FTRACE | |
847 | ||
848 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD | |
849 | # error Dynamic ftrace depends on MCOUNT_RECORD | |
850 | #endif | |
851 | ||
852 | static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly; | |
853 | ||
854 | struct ftrace_func_probe { | |
855 | struct hlist_node node; | |
856 | struct ftrace_probe_ops *ops; | |
857 | unsigned long flags; | |
858 | unsigned long ip; | |
859 | void *data; | |
860 | struct rcu_head rcu; | |
861 | }; | |
862 | ||
863 | enum { | |
864 | FTRACE_ENABLE_CALLS = (1 << 0), | |
865 | FTRACE_DISABLE_CALLS = (1 << 1), | |
866 | FTRACE_UPDATE_TRACE_FUNC = (1 << 2), | |
79e406d7 SR |
867 | FTRACE_START_FUNC_RET = (1 << 3), |
868 | FTRACE_STOP_FUNC_RET = (1 << 4), | |
493762fc | 869 | }; |
b448c4e3 SR |
870 | struct ftrace_func_entry { |
871 | struct hlist_node hlist; | |
872 | unsigned long ip; | |
873 | }; | |
874 | ||
875 | struct ftrace_hash { | |
876 | unsigned long size_bits; | |
877 | struct hlist_head *buckets; | |
878 | unsigned long count; | |
879 | }; | |
880 | ||
33dc9b12 SR |
881 | /* |
882 | * We make these constant because no one should touch them, | |
883 | * but they are used as the default "empty hash", to avoid allocating | |
884 | * it all the time. These are in a read only section such that if | |
885 | * anyone does try to modify it, it will cause an exception. | |
886 | */ | |
887 | static const struct hlist_head empty_buckets[1]; | |
888 | static const struct ftrace_hash empty_hash = { | |
889 | .buckets = (struct hlist_head *)empty_buckets, | |
1cf41dd7 | 890 | }; |
33dc9b12 | 891 | #define EMPTY_HASH ((struct ftrace_hash *)&empty_hash) |
493762fc | 892 | |
ed926f9b SR |
893 | enum { |
894 | FTRACE_OPS_FL_ENABLED = 1, | |
895 | }; | |
896 | ||
f45948e8 SR |
897 | struct ftrace_ops global_ops = { |
898 | .func = ftrace_stub, | |
33dc9b12 SR |
899 | .notrace_hash = EMPTY_HASH, |
900 | .filter_hash = EMPTY_HASH, | |
f45948e8 SR |
901 | }; |
902 | ||
493762fc SR |
903 | static struct dyn_ftrace *ftrace_new_addrs; |
904 | ||
905 | static DEFINE_MUTEX(ftrace_regex_lock); | |
906 | ||
907 | struct ftrace_page { | |
908 | struct ftrace_page *next; | |
909 | int index; | |
910 | struct dyn_ftrace records[]; | |
911 | }; | |
912 | ||
913 | #define ENTRIES_PER_PAGE \ | |
914 | ((PAGE_SIZE - sizeof(struct ftrace_page)) / sizeof(struct dyn_ftrace)) | |
915 | ||
916 | /* estimate from running different kernels */ | |
917 | #define NR_TO_INIT 10000 | |
918 | ||
919 | static struct ftrace_page *ftrace_pages_start; | |
920 | static struct ftrace_page *ftrace_pages; | |
921 | ||
922 | static struct dyn_ftrace *ftrace_free_records; | |
923 | ||
b448c4e3 SR |
924 | static struct ftrace_func_entry * |
925 | ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
926 | { | |
927 | unsigned long key; | |
928 | struct ftrace_func_entry *entry; | |
929 | struct hlist_head *hhd; | |
930 | struct hlist_node *n; | |
931 | ||
932 | if (!hash->count) | |
933 | return NULL; | |
934 | ||
935 | if (hash->size_bits > 0) | |
936 | key = hash_long(ip, hash->size_bits); | |
937 | else | |
938 | key = 0; | |
939 | ||
940 | hhd = &hash->buckets[key]; | |
941 | ||
942 | hlist_for_each_entry_rcu(entry, n, hhd, hlist) { | |
943 | if (entry->ip == ip) | |
944 | return entry; | |
945 | } | |
946 | return NULL; | |
947 | } | |
948 | ||
33dc9b12 SR |
949 | static void __add_hash_entry(struct ftrace_hash *hash, |
950 | struct ftrace_func_entry *entry) | |
b448c4e3 | 951 | { |
b448c4e3 SR |
952 | struct hlist_head *hhd; |
953 | unsigned long key; | |
954 | ||
b448c4e3 | 955 | if (hash->size_bits) |
33dc9b12 | 956 | key = hash_long(entry->ip, hash->size_bits); |
b448c4e3 SR |
957 | else |
958 | key = 0; | |
959 | ||
b448c4e3 SR |
960 | hhd = &hash->buckets[key]; |
961 | hlist_add_head(&entry->hlist, hhd); | |
962 | hash->count++; | |
33dc9b12 SR |
963 | } |
964 | ||
965 | static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) | |
966 | { | |
967 | struct ftrace_func_entry *entry; | |
968 | ||
969 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
970 | if (!entry) | |
971 | return -ENOMEM; | |
972 | ||
973 | entry->ip = ip; | |
974 | __add_hash_entry(hash, entry); | |
b448c4e3 SR |
975 | |
976 | return 0; | |
977 | } | |
978 | ||
979 | static void | |
33dc9b12 | 980 | free_hash_entry(struct ftrace_hash *hash, |
b448c4e3 SR |
981 | struct ftrace_func_entry *entry) |
982 | { | |
983 | hlist_del(&entry->hlist); | |
984 | kfree(entry); | |
985 | hash->count--; | |
986 | } | |
987 | ||
33dc9b12 SR |
988 | static void |
989 | remove_hash_entry(struct ftrace_hash *hash, | |
990 | struct ftrace_func_entry *entry) | |
991 | { | |
992 | hlist_del(&entry->hlist); | |
993 | hash->count--; | |
994 | } | |
995 | ||
b448c4e3 SR |
996 | static void ftrace_hash_clear(struct ftrace_hash *hash) |
997 | { | |
998 | struct hlist_head *hhd; | |
999 | struct hlist_node *tp, *tn; | |
1000 | struct ftrace_func_entry *entry; | |
1001 | int size = 1 << hash->size_bits; | |
1002 | int i; | |
1003 | ||
33dc9b12 SR |
1004 | if (!hash->count) |
1005 | return; | |
1006 | ||
b448c4e3 SR |
1007 | for (i = 0; i < size; i++) { |
1008 | hhd = &hash->buckets[i]; | |
1009 | hlist_for_each_entry_safe(entry, tp, tn, hhd, hlist) | |
33dc9b12 | 1010 | free_hash_entry(hash, entry); |
b448c4e3 SR |
1011 | } |
1012 | FTRACE_WARN_ON(hash->count); | |
1013 | } | |
1014 | ||
33dc9b12 SR |
1015 | static void free_ftrace_hash(struct ftrace_hash *hash) |
1016 | { | |
1017 | if (!hash || hash == EMPTY_HASH) | |
1018 | return; | |
1019 | ftrace_hash_clear(hash); | |
1020 | kfree(hash->buckets); | |
1021 | kfree(hash); | |
1022 | } | |
1023 | ||
1024 | static struct ftrace_hash *alloc_ftrace_hash(int size_bits) | |
1025 | { | |
1026 | struct ftrace_hash *hash; | |
1027 | int size; | |
1028 | ||
1029 | hash = kzalloc(sizeof(*hash), GFP_KERNEL); | |
1030 | if (!hash) | |
1031 | return NULL; | |
1032 | ||
1033 | size = 1 << size_bits; | |
1034 | hash->buckets = kzalloc(sizeof(*hash->buckets) * size, GFP_KERNEL); | |
1035 | ||
1036 | if (!hash->buckets) { | |
1037 | kfree(hash); | |
1038 | return NULL; | |
1039 | } | |
1040 | ||
1041 | hash->size_bits = size_bits; | |
1042 | ||
1043 | return hash; | |
1044 | } | |
1045 | ||
1046 | static struct ftrace_hash * | |
1047 | alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) | |
1048 | { | |
1049 | struct ftrace_func_entry *entry; | |
1050 | struct ftrace_hash *new_hash; | |
1051 | struct hlist_node *tp; | |
1052 | int size; | |
1053 | int ret; | |
1054 | int i; | |
1055 | ||
1056 | new_hash = alloc_ftrace_hash(size_bits); | |
1057 | if (!new_hash) | |
1058 | return NULL; | |
1059 | ||
1060 | /* Empty hash? */ | |
1061 | if (!hash || !hash->count) | |
1062 | return new_hash; | |
1063 | ||
1064 | size = 1 << hash->size_bits; | |
1065 | for (i = 0; i < size; i++) { | |
1066 | hlist_for_each_entry(entry, tp, &hash->buckets[i], hlist) { | |
1067 | ret = add_hash_entry(new_hash, entry->ip); | |
1068 | if (ret < 0) | |
1069 | goto free_hash; | |
1070 | } | |
1071 | } | |
1072 | ||
1073 | FTRACE_WARN_ON(new_hash->count != hash->count); | |
1074 | ||
1075 | return new_hash; | |
1076 | ||
1077 | free_hash: | |
1078 | free_ftrace_hash(new_hash); | |
1079 | return NULL; | |
1080 | } | |
1081 | ||
1082 | static int | |
1083 | ftrace_hash_move(struct ftrace_hash **dst, struct ftrace_hash *src) | |
1084 | { | |
1085 | struct ftrace_func_entry *entry; | |
1086 | struct hlist_node *tp, *tn; | |
1087 | struct hlist_head *hhd; | |
1088 | struct ftrace_hash *hash = *dst; | |
1089 | unsigned long key; | |
1090 | int size = src->count; | |
1091 | int bits = 0; | |
1092 | int i; | |
1093 | ||
1094 | /* | |
1095 | * If the new source is empty, just free dst and assign it | |
1096 | * the empty_hash. | |
1097 | */ | |
1098 | if (!src->count) { | |
1099 | free_ftrace_hash(*dst); | |
1100 | *dst = EMPTY_HASH; | |
1101 | return 0; | |
1102 | } | |
1103 | ||
1104 | ftrace_hash_clear(hash); | |
1105 | ||
1106 | /* | |
1107 | * Make the hash size about 1/2 the # found | |
1108 | */ | |
1109 | for (size /= 2; size; size >>= 1) | |
1110 | bits++; | |
1111 | ||
1112 | /* Don't allocate too much */ | |
1113 | if (bits > FTRACE_HASH_MAX_BITS) | |
1114 | bits = FTRACE_HASH_MAX_BITS; | |
1115 | ||
1116 | /* We can't modify the empty_hash */ | |
1117 | if (hash == EMPTY_HASH) { | |
1118 | /* Create a new hash */ | |
1119 | *dst = alloc_ftrace_hash(bits); | |
1120 | if (!*dst) { | |
1121 | *dst = EMPTY_HASH; | |
1122 | return -ENOMEM; | |
1123 | } | |
1124 | hash = *dst; | |
1125 | } else { | |
1126 | size = 1 << bits; | |
1127 | ||
1128 | /* Use the old hash, but create new buckets */ | |
1129 | hhd = kzalloc(sizeof(*hhd) * size, GFP_KERNEL); | |
1130 | if (!hhd) | |
1131 | return -ENOMEM; | |
1132 | ||
1133 | kfree(hash->buckets); | |
1134 | hash->buckets = hhd; | |
1135 | hash->size_bits = bits; | |
1136 | } | |
1137 | ||
1138 | size = 1 << src->size_bits; | |
1139 | for (i = 0; i < size; i++) { | |
1140 | hhd = &src->buckets[i]; | |
1141 | hlist_for_each_entry_safe(entry, tp, tn, hhd, hlist) { | |
1142 | if (bits > 0) | |
1143 | key = hash_long(entry->ip, bits); | |
1144 | else | |
1145 | key = 0; | |
1146 | remove_hash_entry(src, entry); | |
1147 | __add_hash_entry(hash, entry); | |
1148 | } | |
1149 | } | |
1150 | ||
1151 | return 0; | |
1152 | } | |
1153 | ||
493762fc SR |
1154 | /* |
1155 | * This is a double for. Do not use 'break' to break out of the loop, | |
1156 | * you must use a goto. | |
1157 | */ | |
1158 | #define do_for_each_ftrace_rec(pg, rec) \ | |
1159 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
1160 | int _____i; \ | |
1161 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
1162 | rec = &pg->records[_____i]; | |
1163 | ||
1164 | #define while_for_each_ftrace_rec() \ | |
1165 | } \ | |
1166 | } | |
1167 | ||
ed926f9b SR |
1168 | static void __ftrace_hash_rec_update(struct ftrace_ops *ops, |
1169 | int filter_hash, | |
1170 | bool inc) | |
1171 | { | |
1172 | struct ftrace_hash *hash; | |
1173 | struct ftrace_hash *other_hash; | |
1174 | struct ftrace_page *pg; | |
1175 | struct dyn_ftrace *rec; | |
1176 | int count = 0; | |
1177 | int all = 0; | |
1178 | ||
1179 | /* Only update if the ops has been registered */ | |
1180 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
1181 | return; | |
1182 | ||
1183 | /* | |
1184 | * In the filter_hash case: | |
1185 | * If the count is zero, we update all records. | |
1186 | * Otherwise we just update the items in the hash. | |
1187 | * | |
1188 | * In the notrace_hash case: | |
1189 | * We enable the update in the hash. | |
1190 | * As disabling notrace means enabling the tracing, | |
1191 | * and enabling notrace means disabling, the inc variable | |
1192 | * gets inversed. | |
1193 | */ | |
1194 | if (filter_hash) { | |
1195 | hash = ops->filter_hash; | |
1196 | other_hash = ops->notrace_hash; | |
1197 | if (!hash->count) | |
1198 | all = 1; | |
1199 | } else { | |
1200 | inc = !inc; | |
1201 | hash = ops->notrace_hash; | |
1202 | other_hash = ops->filter_hash; | |
1203 | /* | |
1204 | * If the notrace hash has no items, | |
1205 | * then there's nothing to do. | |
1206 | */ | |
1207 | if (!hash->count) | |
1208 | return; | |
1209 | } | |
1210 | ||
1211 | do_for_each_ftrace_rec(pg, rec) { | |
1212 | int in_other_hash = 0; | |
1213 | int in_hash = 0; | |
1214 | int match = 0; | |
1215 | ||
1216 | if (all) { | |
1217 | /* | |
1218 | * Only the filter_hash affects all records. | |
1219 | * Update if the record is not in the notrace hash. | |
1220 | */ | |
1221 | if (!ftrace_lookup_ip(other_hash, rec->ip)) | |
1222 | match = 1; | |
1223 | } else { | |
1224 | in_hash = !!ftrace_lookup_ip(hash, rec->ip); | |
1225 | in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip); | |
1226 | ||
1227 | /* | |
1228 | * | |
1229 | */ | |
1230 | if (filter_hash && in_hash && !in_other_hash) | |
1231 | match = 1; | |
1232 | else if (!filter_hash && in_hash && | |
1233 | (in_other_hash || !other_hash->count)) | |
1234 | match = 1; | |
1235 | } | |
1236 | if (!match) | |
1237 | continue; | |
1238 | ||
1239 | if (inc) { | |
1240 | rec->flags++; | |
1241 | if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == FTRACE_REF_MAX)) | |
1242 | return; | |
1243 | } else { | |
1244 | if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == 0)) | |
1245 | return; | |
1246 | rec->flags--; | |
1247 | } | |
1248 | count++; | |
1249 | /* Shortcut, if we handled all records, we are done. */ | |
1250 | if (!all && count == hash->count) | |
1251 | return; | |
1252 | } while_for_each_ftrace_rec(); | |
1253 | } | |
1254 | ||
1255 | static void ftrace_hash_rec_disable(struct ftrace_ops *ops, | |
1256 | int filter_hash) | |
1257 | { | |
1258 | __ftrace_hash_rec_update(ops, filter_hash, 0); | |
1259 | } | |
1260 | ||
1261 | static void ftrace_hash_rec_enable(struct ftrace_ops *ops, | |
1262 | int filter_hash) | |
1263 | { | |
1264 | __ftrace_hash_rec_update(ops, filter_hash, 1); | |
1265 | } | |
1266 | ||
e309b41d | 1267 | static void ftrace_free_rec(struct dyn_ftrace *rec) |
37ad5084 | 1268 | { |
ee000b7f | 1269 | rec->freelist = ftrace_free_records; |
37ad5084 SR |
1270 | ftrace_free_records = rec; |
1271 | rec->flags |= FTRACE_FL_FREE; | |
1272 | } | |
1273 | ||
e309b41d | 1274 | static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip) |
3c1720f0 | 1275 | { |
37ad5084 SR |
1276 | struct dyn_ftrace *rec; |
1277 | ||
1278 | /* First check for freed records */ | |
1279 | if (ftrace_free_records) { | |
1280 | rec = ftrace_free_records; | |
1281 | ||
37ad5084 | 1282 | if (unlikely(!(rec->flags & FTRACE_FL_FREE))) { |
6912896e | 1283 | FTRACE_WARN_ON_ONCE(1); |
37ad5084 SR |
1284 | ftrace_free_records = NULL; |
1285 | return NULL; | |
1286 | } | |
1287 | ||
ee000b7f | 1288 | ftrace_free_records = rec->freelist; |
37ad5084 SR |
1289 | memset(rec, 0, sizeof(*rec)); |
1290 | return rec; | |
1291 | } | |
1292 | ||
3c1720f0 | 1293 | if (ftrace_pages->index == ENTRIES_PER_PAGE) { |
08f5ac90 SR |
1294 | if (!ftrace_pages->next) { |
1295 | /* allocate another page */ | |
1296 | ftrace_pages->next = | |
1297 | (void *)get_zeroed_page(GFP_KERNEL); | |
1298 | if (!ftrace_pages->next) | |
1299 | return NULL; | |
1300 | } | |
3c1720f0 SR |
1301 | ftrace_pages = ftrace_pages->next; |
1302 | } | |
1303 | ||
1304 | return &ftrace_pages->records[ftrace_pages->index++]; | |
1305 | } | |
1306 | ||
08f5ac90 | 1307 | static struct dyn_ftrace * |
d61f82d0 | 1308 | ftrace_record_ip(unsigned long ip) |
3d083395 | 1309 | { |
08f5ac90 | 1310 | struct dyn_ftrace *rec; |
3d083395 | 1311 | |
f3c7ac40 | 1312 | if (ftrace_disabled) |
08f5ac90 | 1313 | return NULL; |
3d083395 | 1314 | |
08f5ac90 SR |
1315 | rec = ftrace_alloc_dyn_node(ip); |
1316 | if (!rec) | |
1317 | return NULL; | |
3d083395 | 1318 | |
08f5ac90 | 1319 | rec->ip = ip; |
ee000b7f | 1320 | rec->newlist = ftrace_new_addrs; |
e94142a6 | 1321 | ftrace_new_addrs = rec; |
3d083395 | 1322 | |
08f5ac90 | 1323 | return rec; |
3d083395 SR |
1324 | } |
1325 | ||
b17e8a37 SR |
1326 | static void print_ip_ins(const char *fmt, unsigned char *p) |
1327 | { | |
1328 | int i; | |
1329 | ||
1330 | printk(KERN_CONT "%s", fmt); | |
1331 | ||
1332 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
1333 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
1334 | } | |
1335 | ||
31e88909 | 1336 | static void ftrace_bug(int failed, unsigned long ip) |
b17e8a37 SR |
1337 | { |
1338 | switch (failed) { | |
1339 | case -EFAULT: | |
1340 | FTRACE_WARN_ON_ONCE(1); | |
1341 | pr_info("ftrace faulted on modifying "); | |
1342 | print_ip_sym(ip); | |
1343 | break; | |
1344 | case -EINVAL: | |
1345 | FTRACE_WARN_ON_ONCE(1); | |
1346 | pr_info("ftrace failed to modify "); | |
1347 | print_ip_sym(ip); | |
b17e8a37 | 1348 | print_ip_ins(" actual: ", (unsigned char *)ip); |
b17e8a37 SR |
1349 | printk(KERN_CONT "\n"); |
1350 | break; | |
1351 | case -EPERM: | |
1352 | FTRACE_WARN_ON_ONCE(1); | |
1353 | pr_info("ftrace faulted on writing "); | |
1354 | print_ip_sym(ip); | |
1355 | break; | |
1356 | default: | |
1357 | FTRACE_WARN_ON_ONCE(1); | |
1358 | pr_info("ftrace faulted on unknown error "); | |
1359 | print_ip_sym(ip); | |
1360 | } | |
1361 | } | |
1362 | ||
3c1720f0 | 1363 | |
2cfa1978 MH |
1364 | /* Return 1 if the address range is reserved for ftrace */ |
1365 | int ftrace_text_reserved(void *start, void *end) | |
1366 | { | |
1367 | struct dyn_ftrace *rec; | |
1368 | struct ftrace_page *pg; | |
1369 | ||
1370 | do_for_each_ftrace_rec(pg, rec) { | |
1371 | if (rec->ip <= (unsigned long)end && | |
1372 | rec->ip + MCOUNT_INSN_SIZE > (unsigned long)start) | |
1373 | return 1; | |
1374 | } while_for_each_ftrace_rec(); | |
1375 | return 0; | |
1376 | } | |
1377 | ||
1378 | ||
0eb96701 | 1379 | static int |
31e88909 | 1380 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) |
5072c59f | 1381 | { |
e7d3737e | 1382 | unsigned long ftrace_addr; |
64fbcd16 | 1383 | unsigned long flag = 0UL; |
e7d3737e | 1384 | |
f0001207 | 1385 | ftrace_addr = (unsigned long)FTRACE_ADDR; |
5072c59f | 1386 | |
982c350b | 1387 | /* |
ed926f9b | 1388 | * If we are enabling tracing: |
982c350b | 1389 | * |
ed926f9b SR |
1390 | * If the record has a ref count, then we need to enable it |
1391 | * because someone is using it. | |
982c350b | 1392 | * |
ed926f9b SR |
1393 | * Otherwise we make sure its disabled. |
1394 | * | |
1395 | * If we are disabling tracing, then disable all records that | |
1396 | * are enabled. | |
982c350b | 1397 | */ |
ed926f9b SR |
1398 | if (enable && (rec->flags & ~FTRACE_FL_MASK)) |
1399 | flag = FTRACE_FL_ENABLED; | |
982c350b | 1400 | |
64fbcd16 XG |
1401 | /* If the state of this record hasn't changed, then do nothing */ |
1402 | if ((rec->flags & FTRACE_FL_ENABLED) == flag) | |
1403 | return 0; | |
982c350b | 1404 | |
64fbcd16 XG |
1405 | if (flag) { |
1406 | rec->flags |= FTRACE_FL_ENABLED; | |
1407 | return ftrace_make_call(rec, ftrace_addr); | |
5072c59f SR |
1408 | } |
1409 | ||
64fbcd16 XG |
1410 | rec->flags &= ~FTRACE_FL_ENABLED; |
1411 | return ftrace_make_nop(NULL, rec, ftrace_addr); | |
5072c59f SR |
1412 | } |
1413 | ||
e309b41d | 1414 | static void ftrace_replace_code(int enable) |
3c1720f0 | 1415 | { |
3c1720f0 SR |
1416 | struct dyn_ftrace *rec; |
1417 | struct ftrace_page *pg; | |
6a24a244 | 1418 | int failed; |
3c1720f0 | 1419 | |
45a4a237 SR |
1420 | if (unlikely(ftrace_disabled)) |
1421 | return; | |
1422 | ||
265c831c | 1423 | do_for_each_ftrace_rec(pg, rec) { |
d2c8c3ea SR |
1424 | /* Skip over free records */ |
1425 | if (rec->flags & FTRACE_FL_FREE) | |
265c831c SR |
1426 | continue; |
1427 | ||
265c831c | 1428 | failed = __ftrace_replace_code(rec, enable); |
fa9d13cf | 1429 | if (failed) { |
3279ba37 SR |
1430 | ftrace_bug(failed, rec->ip); |
1431 | /* Stop processing */ | |
1432 | return; | |
3c1720f0 | 1433 | } |
265c831c | 1434 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
1435 | } |
1436 | ||
492a7ea5 | 1437 | static int |
31e88909 | 1438 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 SR |
1439 | { |
1440 | unsigned long ip; | |
593eb8a2 | 1441 | int ret; |
3c1720f0 SR |
1442 | |
1443 | ip = rec->ip; | |
1444 | ||
45a4a237 SR |
1445 | if (unlikely(ftrace_disabled)) |
1446 | return 0; | |
1447 | ||
25aac9dc | 1448 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
593eb8a2 | 1449 | if (ret) { |
31e88909 | 1450 | ftrace_bug(ret, ip); |
492a7ea5 | 1451 | return 0; |
37ad5084 | 1452 | } |
492a7ea5 | 1453 | return 1; |
3c1720f0 SR |
1454 | } |
1455 | ||
000ab691 SR |
1456 | /* |
1457 | * archs can override this function if they must do something | |
1458 | * before the modifying code is performed. | |
1459 | */ | |
1460 | int __weak ftrace_arch_code_modify_prepare(void) | |
1461 | { | |
1462 | return 0; | |
1463 | } | |
1464 | ||
1465 | /* | |
1466 | * archs can override this function if they must do something | |
1467 | * after the modifying code is performed. | |
1468 | */ | |
1469 | int __weak ftrace_arch_code_modify_post_process(void) | |
1470 | { | |
1471 | return 0; | |
1472 | } | |
1473 | ||
e309b41d | 1474 | static int __ftrace_modify_code(void *data) |
3d083395 | 1475 | { |
d61f82d0 SR |
1476 | int *command = data; |
1477 | ||
a3583244 | 1478 | if (*command & FTRACE_ENABLE_CALLS) |
d61f82d0 | 1479 | ftrace_replace_code(1); |
a3583244 | 1480 | else if (*command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
1481 | ftrace_replace_code(0); |
1482 | ||
1483 | if (*command & FTRACE_UPDATE_TRACE_FUNC) | |
1484 | ftrace_update_ftrace_func(ftrace_trace_function); | |
1485 | ||
5a45cfe1 SR |
1486 | if (*command & FTRACE_START_FUNC_RET) |
1487 | ftrace_enable_ftrace_graph_caller(); | |
1488 | else if (*command & FTRACE_STOP_FUNC_RET) | |
1489 | ftrace_disable_ftrace_graph_caller(); | |
1490 | ||
d61f82d0 | 1491 | return 0; |
3d083395 SR |
1492 | } |
1493 | ||
e309b41d | 1494 | static void ftrace_run_update_code(int command) |
3d083395 | 1495 | { |
000ab691 SR |
1496 | int ret; |
1497 | ||
1498 | ret = ftrace_arch_code_modify_prepare(); | |
1499 | FTRACE_WARN_ON(ret); | |
1500 | if (ret) | |
1501 | return; | |
1502 | ||
784e2d76 | 1503 | stop_machine(__ftrace_modify_code, &command, NULL); |
000ab691 SR |
1504 | |
1505 | ret = ftrace_arch_code_modify_post_process(); | |
1506 | FTRACE_WARN_ON(ret); | |
3d083395 SR |
1507 | } |
1508 | ||
d61f82d0 | 1509 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 1510 | static int ftrace_start_up; |
df4fc315 SR |
1511 | |
1512 | static void ftrace_startup_enable(int command) | |
1513 | { | |
1514 | if (saved_ftrace_func != ftrace_trace_function) { | |
1515 | saved_ftrace_func = ftrace_trace_function; | |
1516 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
1517 | } | |
1518 | ||
1519 | if (!command || !ftrace_enabled) | |
1520 | return; | |
1521 | ||
1522 | ftrace_run_update_code(command); | |
1523 | } | |
d61f82d0 | 1524 | |
5a45cfe1 | 1525 | static void ftrace_startup(int command) |
3d083395 | 1526 | { |
ed926f9b SR |
1527 | struct ftrace_ops *ops = &global_ops; |
1528 | ||
4eebcc81 SR |
1529 | if (unlikely(ftrace_disabled)) |
1530 | return; | |
1531 | ||
60a7ecf4 | 1532 | ftrace_start_up++; |
982c350b | 1533 | command |= FTRACE_ENABLE_CALLS; |
d61f82d0 | 1534 | |
ed926f9b SR |
1535 | ops->flags |= FTRACE_OPS_FL_ENABLED; |
1536 | if (ftrace_start_up == 1) | |
1537 | ftrace_hash_rec_enable(ops, 1); | |
1538 | ||
df4fc315 | 1539 | ftrace_startup_enable(command); |
3d083395 SR |
1540 | } |
1541 | ||
5a45cfe1 | 1542 | static void ftrace_shutdown(int command) |
3d083395 | 1543 | { |
ed926f9b SR |
1544 | struct ftrace_ops *ops = &global_ops; |
1545 | ||
4eebcc81 SR |
1546 | if (unlikely(ftrace_disabled)) |
1547 | return; | |
1548 | ||
60a7ecf4 | 1549 | ftrace_start_up--; |
9ea1a153 FW |
1550 | /* |
1551 | * Just warn in case of unbalance, no need to kill ftrace, it's not | |
1552 | * critical but the ftrace_call callers may be never nopped again after | |
1553 | * further ftrace uses. | |
1554 | */ | |
1555 | WARN_ON_ONCE(ftrace_start_up < 0); | |
1556 | ||
60a7ecf4 | 1557 | if (!ftrace_start_up) |
ed926f9b SR |
1558 | ftrace_hash_rec_disable(ops, 1); |
1559 | ||
1560 | if (!ftrace_start_up) { | |
d61f82d0 | 1561 | command |= FTRACE_DISABLE_CALLS; |
ed926f9b SR |
1562 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; |
1563 | } | |
3d083395 | 1564 | |
d61f82d0 SR |
1565 | if (saved_ftrace_func != ftrace_trace_function) { |
1566 | saved_ftrace_func = ftrace_trace_function; | |
1567 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
1568 | } | |
3d083395 | 1569 | |
d61f82d0 | 1570 | if (!command || !ftrace_enabled) |
e6ea44e9 | 1571 | return; |
d61f82d0 SR |
1572 | |
1573 | ftrace_run_update_code(command); | |
3d083395 SR |
1574 | } |
1575 | ||
e309b41d | 1576 | static void ftrace_startup_sysctl(void) |
b0fc494f | 1577 | { |
4eebcc81 SR |
1578 | if (unlikely(ftrace_disabled)) |
1579 | return; | |
1580 | ||
d61f82d0 SR |
1581 | /* Force update next time */ |
1582 | saved_ftrace_func = NULL; | |
60a7ecf4 SR |
1583 | /* ftrace_start_up is true if we want ftrace running */ |
1584 | if (ftrace_start_up) | |
79e406d7 | 1585 | ftrace_run_update_code(FTRACE_ENABLE_CALLS); |
b0fc494f SR |
1586 | } |
1587 | ||
e309b41d | 1588 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 1589 | { |
4eebcc81 SR |
1590 | if (unlikely(ftrace_disabled)) |
1591 | return; | |
1592 | ||
60a7ecf4 SR |
1593 | /* ftrace_start_up is true if ftrace is running */ |
1594 | if (ftrace_start_up) | |
79e406d7 | 1595 | ftrace_run_update_code(FTRACE_DISABLE_CALLS); |
b0fc494f SR |
1596 | } |
1597 | ||
3d083395 SR |
1598 | static cycle_t ftrace_update_time; |
1599 | static unsigned long ftrace_update_cnt; | |
1600 | unsigned long ftrace_update_tot_cnt; | |
1601 | ||
31e88909 | 1602 | static int ftrace_update_code(struct module *mod) |
3d083395 | 1603 | { |
e94142a6 | 1604 | struct dyn_ftrace *p; |
f22f9a89 | 1605 | cycle_t start, stop; |
3d083395 | 1606 | |
750ed1a4 | 1607 | start = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
1608 | ftrace_update_cnt = 0; |
1609 | ||
e94142a6 | 1610 | while (ftrace_new_addrs) { |
3d083395 | 1611 | |
08f5ac90 SR |
1612 | /* If something went wrong, bail without enabling anything */ |
1613 | if (unlikely(ftrace_disabled)) | |
1614 | return -1; | |
f22f9a89 | 1615 | |
e94142a6 | 1616 | p = ftrace_new_addrs; |
ee000b7f | 1617 | ftrace_new_addrs = p->newlist; |
e94142a6 | 1618 | p->flags = 0L; |
f22f9a89 | 1619 | |
5cb084bb | 1620 | /* |
25985edc | 1621 | * Do the initial record conversion from mcount jump |
5cb084bb JO |
1622 | * to the NOP instructions. |
1623 | */ | |
1624 | if (!ftrace_code_disable(mod, p)) { | |
08f5ac90 | 1625 | ftrace_free_rec(p); |
d2c8c3ea SR |
1626 | /* Game over */ |
1627 | break; | |
5cb084bb JO |
1628 | } |
1629 | ||
5cb084bb JO |
1630 | ftrace_update_cnt++; |
1631 | ||
1632 | /* | |
1633 | * If the tracing is enabled, go ahead and enable the record. | |
1634 | * | |
1635 | * The reason not to enable the record immediatelly is the | |
1636 | * inherent check of ftrace_make_nop/ftrace_make_call for | |
1637 | * correct previous instructions. Making first the NOP | |
1638 | * conversion puts the module to the correct state, thus | |
1639 | * passing the ftrace_make_call check. | |
1640 | */ | |
1641 | if (ftrace_start_up) { | |
1642 | int failed = __ftrace_replace_code(p, 1); | |
1643 | if (failed) { | |
1644 | ftrace_bug(failed, p->ip); | |
1645 | ftrace_free_rec(p); | |
1646 | } | |
1647 | } | |
3d083395 SR |
1648 | } |
1649 | ||
750ed1a4 | 1650 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
1651 | ftrace_update_time = stop - start; |
1652 | ftrace_update_tot_cnt += ftrace_update_cnt; | |
1653 | ||
16444a8a ACM |
1654 | return 0; |
1655 | } | |
1656 | ||
68bf21aa | 1657 | static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) |
3c1720f0 SR |
1658 | { |
1659 | struct ftrace_page *pg; | |
1660 | int cnt; | |
1661 | int i; | |
3c1720f0 SR |
1662 | |
1663 | /* allocate a few pages */ | |
1664 | ftrace_pages_start = (void *)get_zeroed_page(GFP_KERNEL); | |
1665 | if (!ftrace_pages_start) | |
1666 | return -1; | |
1667 | ||
1668 | /* | |
1669 | * Allocate a few more pages. | |
1670 | * | |
1671 | * TODO: have some parser search vmlinux before | |
1672 | * final linking to find all calls to ftrace. | |
1673 | * Then we can: | |
1674 | * a) know how many pages to allocate. | |
1675 | * and/or | |
1676 | * b) set up the table then. | |
1677 | * | |
1678 | * The dynamic code is still necessary for | |
1679 | * modules. | |
1680 | */ | |
1681 | ||
1682 | pg = ftrace_pages = ftrace_pages_start; | |
1683 | ||
68bf21aa | 1684 | cnt = num_to_init / ENTRIES_PER_PAGE; |
08f5ac90 | 1685 | pr_info("ftrace: allocating %ld entries in %d pages\n", |
5821e1b7 | 1686 | num_to_init, cnt + 1); |
3c1720f0 SR |
1687 | |
1688 | for (i = 0; i < cnt; i++) { | |
1689 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); | |
1690 | ||
1691 | /* If we fail, we'll try later anyway */ | |
1692 | if (!pg->next) | |
1693 | break; | |
1694 | ||
1695 | pg = pg->next; | |
1696 | } | |
1697 | ||
1698 | return 0; | |
1699 | } | |
1700 | ||
5072c59f SR |
1701 | enum { |
1702 | FTRACE_ITER_FILTER = (1 << 0), | |
689fd8b6 | 1703 | FTRACE_ITER_NOTRACE = (1 << 1), |
3499e461 SR |
1704 | FTRACE_ITER_PRINTALL = (1 << 2), |
1705 | FTRACE_ITER_HASH = (1 << 3), | |
5072c59f SR |
1706 | }; |
1707 | ||
1708 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ | |
1709 | ||
1710 | struct ftrace_iterator { | |
98c4fd04 | 1711 | loff_t pos; |
4aeb6967 SR |
1712 | loff_t func_pos; |
1713 | struct ftrace_page *pg; | |
1714 | struct dyn_ftrace *func; | |
1715 | struct ftrace_func_probe *probe; | |
1716 | struct trace_parser parser; | |
1cf41dd7 | 1717 | struct ftrace_hash *hash; |
33dc9b12 | 1718 | struct ftrace_ops *ops; |
4aeb6967 SR |
1719 | int hidx; |
1720 | int idx; | |
1721 | unsigned flags; | |
5072c59f SR |
1722 | }; |
1723 | ||
8fc0c701 | 1724 | static void * |
4aeb6967 | 1725 | t_hash_next(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
1726 | { |
1727 | struct ftrace_iterator *iter = m->private; | |
4aeb6967 | 1728 | struct hlist_node *hnd = NULL; |
8fc0c701 SR |
1729 | struct hlist_head *hhd; |
1730 | ||
8fc0c701 | 1731 | (*pos)++; |
98c4fd04 | 1732 | iter->pos = *pos; |
8fc0c701 | 1733 | |
4aeb6967 SR |
1734 | if (iter->probe) |
1735 | hnd = &iter->probe->node; | |
8fc0c701 SR |
1736 | retry: |
1737 | if (iter->hidx >= FTRACE_FUNC_HASHSIZE) | |
1738 | return NULL; | |
1739 | ||
1740 | hhd = &ftrace_func_hash[iter->hidx]; | |
1741 | ||
1742 | if (hlist_empty(hhd)) { | |
1743 | iter->hidx++; | |
1744 | hnd = NULL; | |
1745 | goto retry; | |
1746 | } | |
1747 | ||
1748 | if (!hnd) | |
1749 | hnd = hhd->first; | |
1750 | else { | |
1751 | hnd = hnd->next; | |
1752 | if (!hnd) { | |
1753 | iter->hidx++; | |
1754 | goto retry; | |
1755 | } | |
1756 | } | |
1757 | ||
4aeb6967 SR |
1758 | if (WARN_ON_ONCE(!hnd)) |
1759 | return NULL; | |
1760 | ||
1761 | iter->probe = hlist_entry(hnd, struct ftrace_func_probe, node); | |
1762 | ||
1763 | return iter; | |
8fc0c701 SR |
1764 | } |
1765 | ||
1766 | static void *t_hash_start(struct seq_file *m, loff_t *pos) | |
1767 | { | |
1768 | struct ftrace_iterator *iter = m->private; | |
1769 | void *p = NULL; | |
d82d6244 LZ |
1770 | loff_t l; |
1771 | ||
2bccfffd SR |
1772 | if (iter->func_pos > *pos) |
1773 | return NULL; | |
8fc0c701 | 1774 | |
d82d6244 | 1775 | iter->hidx = 0; |
2bccfffd | 1776 | for (l = 0; l <= (*pos - iter->func_pos); ) { |
4aeb6967 | 1777 | p = t_hash_next(m, &l); |
d82d6244 LZ |
1778 | if (!p) |
1779 | break; | |
1780 | } | |
4aeb6967 SR |
1781 | if (!p) |
1782 | return NULL; | |
1783 | ||
98c4fd04 SR |
1784 | /* Only set this if we have an item */ |
1785 | iter->flags |= FTRACE_ITER_HASH; | |
1786 | ||
4aeb6967 | 1787 | return iter; |
8fc0c701 SR |
1788 | } |
1789 | ||
4aeb6967 SR |
1790 | static int |
1791 | t_hash_show(struct seq_file *m, struct ftrace_iterator *iter) | |
8fc0c701 | 1792 | { |
b6887d79 | 1793 | struct ftrace_func_probe *rec; |
8fc0c701 | 1794 | |
4aeb6967 SR |
1795 | rec = iter->probe; |
1796 | if (WARN_ON_ONCE(!rec)) | |
1797 | return -EIO; | |
8fc0c701 | 1798 | |
809dcf29 SR |
1799 | if (rec->ops->print) |
1800 | return rec->ops->print(m, rec->ip, rec->ops, rec->data); | |
1801 | ||
b375a11a | 1802 | seq_printf(m, "%ps:%ps", (void *)rec->ip, (void *)rec->ops->func); |
8fc0c701 SR |
1803 | |
1804 | if (rec->data) | |
1805 | seq_printf(m, ":%p", rec->data); | |
1806 | seq_putc(m, '\n'); | |
1807 | ||
1808 | return 0; | |
1809 | } | |
1810 | ||
e309b41d | 1811 | static void * |
5072c59f SR |
1812 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1813 | { | |
1814 | struct ftrace_iterator *iter = m->private; | |
f45948e8 | 1815 | struct ftrace_ops *ops = &global_ops; |
5072c59f SR |
1816 | struct dyn_ftrace *rec = NULL; |
1817 | ||
45a4a237 SR |
1818 | if (unlikely(ftrace_disabled)) |
1819 | return NULL; | |
1820 | ||
8fc0c701 | 1821 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 1822 | return t_hash_next(m, pos); |
8fc0c701 | 1823 | |
5072c59f | 1824 | (*pos)++; |
1106b699 | 1825 | iter->pos = iter->func_pos = *pos; |
5072c59f | 1826 | |
0c75a3ed | 1827 | if (iter->flags & FTRACE_ITER_PRINTALL) |
57c072c7 | 1828 | return t_hash_start(m, pos); |
0c75a3ed | 1829 | |
5072c59f SR |
1830 | retry: |
1831 | if (iter->idx >= iter->pg->index) { | |
1832 | if (iter->pg->next) { | |
1833 | iter->pg = iter->pg->next; | |
1834 | iter->idx = 0; | |
1835 | goto retry; | |
1836 | } | |
1837 | } else { | |
1838 | rec = &iter->pg->records[iter->idx++]; | |
a9fdda33 SR |
1839 | if ((rec->flags & FTRACE_FL_FREE) || |
1840 | ||
0183fb1c | 1841 | ((iter->flags & FTRACE_ITER_FILTER) && |
f45948e8 | 1842 | !(ftrace_lookup_ip(ops->filter_hash, rec->ip))) || |
0183fb1c | 1843 | |
41c52c0d | 1844 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
f45948e8 | 1845 | !ftrace_lookup_ip(ops->notrace_hash, rec->ip))) { |
5072c59f SR |
1846 | rec = NULL; |
1847 | goto retry; | |
1848 | } | |
1849 | } | |
1850 | ||
4aeb6967 | 1851 | if (!rec) |
57c072c7 | 1852 | return t_hash_start(m, pos); |
4aeb6967 SR |
1853 | |
1854 | iter->func = rec; | |
1855 | ||
1856 | return iter; | |
5072c59f SR |
1857 | } |
1858 | ||
98c4fd04 SR |
1859 | static void reset_iter_read(struct ftrace_iterator *iter) |
1860 | { | |
1861 | iter->pos = 0; | |
1862 | iter->func_pos = 0; | |
1863 | iter->flags &= ~(FTRACE_ITER_PRINTALL & FTRACE_ITER_HASH); | |
5072c59f SR |
1864 | } |
1865 | ||
1866 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1867 | { | |
1868 | struct ftrace_iterator *iter = m->private; | |
f45948e8 | 1869 | struct ftrace_ops *ops = &global_ops; |
5072c59f | 1870 | void *p = NULL; |
694ce0a5 | 1871 | loff_t l; |
5072c59f | 1872 | |
8fc0c701 | 1873 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
1874 | |
1875 | if (unlikely(ftrace_disabled)) | |
1876 | return NULL; | |
1877 | ||
98c4fd04 SR |
1878 | /* |
1879 | * If an lseek was done, then reset and start from beginning. | |
1880 | */ | |
1881 | if (*pos < iter->pos) | |
1882 | reset_iter_read(iter); | |
1883 | ||
0c75a3ed SR |
1884 | /* |
1885 | * For set_ftrace_filter reading, if we have the filter | |
1886 | * off, we can short cut and just print out that all | |
1887 | * functions are enabled. | |
1888 | */ | |
f45948e8 | 1889 | if (iter->flags & FTRACE_ITER_FILTER && !ops->filter_hash->count) { |
0c75a3ed | 1890 | if (*pos > 0) |
8fc0c701 | 1891 | return t_hash_start(m, pos); |
0c75a3ed | 1892 | iter->flags |= FTRACE_ITER_PRINTALL; |
df091625 CW |
1893 | /* reset in case of seek/pread */ |
1894 | iter->flags &= ~FTRACE_ITER_HASH; | |
0c75a3ed SR |
1895 | return iter; |
1896 | } | |
1897 | ||
8fc0c701 SR |
1898 | if (iter->flags & FTRACE_ITER_HASH) |
1899 | return t_hash_start(m, pos); | |
1900 | ||
98c4fd04 SR |
1901 | /* |
1902 | * Unfortunately, we need to restart at ftrace_pages_start | |
1903 | * every time we let go of the ftrace_mutex. This is because | |
1904 | * those pointers can change without the lock. | |
1905 | */ | |
694ce0a5 LZ |
1906 | iter->pg = ftrace_pages_start; |
1907 | iter->idx = 0; | |
1908 | for (l = 0; l <= *pos; ) { | |
1909 | p = t_next(m, p, &l); | |
1910 | if (!p) | |
1911 | break; | |
50cdaf08 | 1912 | } |
5821e1b7 | 1913 | |
4aeb6967 SR |
1914 | if (!p) { |
1915 | if (iter->flags & FTRACE_ITER_FILTER) | |
1916 | return t_hash_start(m, pos); | |
8fc0c701 | 1917 | |
4aeb6967 SR |
1918 | return NULL; |
1919 | } | |
1920 | ||
1921 | return iter; | |
5072c59f SR |
1922 | } |
1923 | ||
1924 | static void t_stop(struct seq_file *m, void *p) | |
1925 | { | |
8fc0c701 | 1926 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
1927 | } |
1928 | ||
1929 | static int t_show(struct seq_file *m, void *v) | |
1930 | { | |
0c75a3ed | 1931 | struct ftrace_iterator *iter = m->private; |
4aeb6967 | 1932 | struct dyn_ftrace *rec; |
5072c59f | 1933 | |
8fc0c701 | 1934 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 1935 | return t_hash_show(m, iter); |
8fc0c701 | 1936 | |
0c75a3ed SR |
1937 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
1938 | seq_printf(m, "#### all functions enabled ####\n"); | |
1939 | return 0; | |
1940 | } | |
1941 | ||
4aeb6967 SR |
1942 | rec = iter->func; |
1943 | ||
5072c59f SR |
1944 | if (!rec) |
1945 | return 0; | |
1946 | ||
b375a11a | 1947 | seq_printf(m, "%ps\n", (void *)rec->ip); |
5072c59f SR |
1948 | |
1949 | return 0; | |
1950 | } | |
1951 | ||
88e9d34c | 1952 | static const struct seq_operations show_ftrace_seq_ops = { |
5072c59f SR |
1953 | .start = t_start, |
1954 | .next = t_next, | |
1955 | .stop = t_stop, | |
1956 | .show = t_show, | |
1957 | }; | |
1958 | ||
e309b41d | 1959 | static int |
5072c59f SR |
1960 | ftrace_avail_open(struct inode *inode, struct file *file) |
1961 | { | |
1962 | struct ftrace_iterator *iter; | |
1963 | int ret; | |
1964 | ||
4eebcc81 SR |
1965 | if (unlikely(ftrace_disabled)) |
1966 | return -ENODEV; | |
1967 | ||
5072c59f SR |
1968 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
1969 | if (!iter) | |
1970 | return -ENOMEM; | |
1971 | ||
1972 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
1973 | |
1974 | ret = seq_open(file, &show_ftrace_seq_ops); | |
1975 | if (!ret) { | |
1976 | struct seq_file *m = file->private_data; | |
4bf39a94 | 1977 | |
5072c59f | 1978 | m->private = iter; |
4bf39a94 | 1979 | } else { |
5072c59f | 1980 | kfree(iter); |
4bf39a94 | 1981 | } |
5072c59f SR |
1982 | |
1983 | return ret; | |
1984 | } | |
1985 | ||
1cf41dd7 | 1986 | static void ftrace_filter_reset(struct ftrace_hash *hash) |
5072c59f | 1987 | { |
52baf119 | 1988 | mutex_lock(&ftrace_lock); |
1cf41dd7 | 1989 | ftrace_hash_clear(hash); |
52baf119 | 1990 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
1991 | } |
1992 | ||
e309b41d | 1993 | static int |
f45948e8 | 1994 | ftrace_regex_open(struct ftrace_ops *ops, int flag, |
1cf41dd7 | 1995 | struct inode *inode, struct file *file) |
5072c59f SR |
1996 | { |
1997 | struct ftrace_iterator *iter; | |
f45948e8 | 1998 | struct ftrace_hash *hash; |
5072c59f SR |
1999 | int ret = 0; |
2000 | ||
4eebcc81 SR |
2001 | if (unlikely(ftrace_disabled)) |
2002 | return -ENODEV; | |
2003 | ||
5072c59f SR |
2004 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
2005 | if (!iter) | |
2006 | return -ENOMEM; | |
2007 | ||
689fd8b6 | 2008 | if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) { |
2009 | kfree(iter); | |
2010 | return -ENOMEM; | |
2011 | } | |
2012 | ||
f45948e8 SR |
2013 | if (flag & FTRACE_ITER_NOTRACE) |
2014 | hash = ops->notrace_hash; | |
2015 | else | |
2016 | hash = ops->filter_hash; | |
2017 | ||
33dc9b12 SR |
2018 | iter->ops = ops; |
2019 | iter->flags = flag; | |
2020 | ||
2021 | if (file->f_mode & FMODE_WRITE) { | |
2022 | mutex_lock(&ftrace_lock); | |
2023 | iter->hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash); | |
2024 | mutex_unlock(&ftrace_lock); | |
2025 | ||
2026 | if (!iter->hash) { | |
2027 | trace_parser_put(&iter->parser); | |
2028 | kfree(iter); | |
2029 | return -ENOMEM; | |
2030 | } | |
2031 | } | |
1cf41dd7 | 2032 | |
41c52c0d | 2033 | mutex_lock(&ftrace_regex_lock); |
33dc9b12 | 2034 | |
5072c59f | 2035 | if ((file->f_mode & FMODE_WRITE) && |
8650ae32 | 2036 | (file->f_flags & O_TRUNC)) |
33dc9b12 | 2037 | ftrace_filter_reset(iter->hash); |
5072c59f SR |
2038 | |
2039 | if (file->f_mode & FMODE_READ) { | |
2040 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
2041 | |
2042 | ret = seq_open(file, &show_ftrace_seq_ops); | |
2043 | if (!ret) { | |
2044 | struct seq_file *m = file->private_data; | |
2045 | m->private = iter; | |
79fe249c | 2046 | } else { |
33dc9b12 SR |
2047 | /* Failed */ |
2048 | free_ftrace_hash(iter->hash); | |
79fe249c | 2049 | trace_parser_put(&iter->parser); |
5072c59f | 2050 | kfree(iter); |
79fe249c | 2051 | } |
5072c59f SR |
2052 | } else |
2053 | file->private_data = iter; | |
41c52c0d | 2054 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
2055 | |
2056 | return ret; | |
2057 | } | |
2058 | ||
41c52c0d SR |
2059 | static int |
2060 | ftrace_filter_open(struct inode *inode, struct file *file) | |
2061 | { | |
f45948e8 | 2062 | return ftrace_regex_open(&global_ops, FTRACE_ITER_FILTER, |
1cf41dd7 | 2063 | inode, file); |
41c52c0d SR |
2064 | } |
2065 | ||
2066 | static int | |
2067 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
2068 | { | |
f45948e8 | 2069 | return ftrace_regex_open(&global_ops, FTRACE_ITER_NOTRACE, |
1cf41dd7 | 2070 | inode, file); |
41c52c0d SR |
2071 | } |
2072 | ||
e309b41d | 2073 | static loff_t |
41c52c0d | 2074 | ftrace_regex_lseek(struct file *file, loff_t offset, int origin) |
5072c59f SR |
2075 | { |
2076 | loff_t ret; | |
2077 | ||
2078 | if (file->f_mode & FMODE_READ) | |
2079 | ret = seq_lseek(file, offset, origin); | |
2080 | else | |
2081 | file->f_pos = ret = 1; | |
2082 | ||
2083 | return ret; | |
2084 | } | |
2085 | ||
64e7c440 | 2086 | static int ftrace_match(char *str, char *regex, int len, int type) |
9f4801e3 | 2087 | { |
9f4801e3 | 2088 | int matched = 0; |
751e9983 | 2089 | int slen; |
9f4801e3 | 2090 | |
9f4801e3 SR |
2091 | switch (type) { |
2092 | case MATCH_FULL: | |
2093 | if (strcmp(str, regex) == 0) | |
2094 | matched = 1; | |
2095 | break; | |
2096 | case MATCH_FRONT_ONLY: | |
2097 | if (strncmp(str, regex, len) == 0) | |
2098 | matched = 1; | |
2099 | break; | |
2100 | case MATCH_MIDDLE_ONLY: | |
2101 | if (strstr(str, regex)) | |
2102 | matched = 1; | |
2103 | break; | |
2104 | case MATCH_END_ONLY: | |
751e9983 LZ |
2105 | slen = strlen(str); |
2106 | if (slen >= len && memcmp(str + slen - len, regex, len) == 0) | |
9f4801e3 SR |
2107 | matched = 1; |
2108 | break; | |
2109 | } | |
2110 | ||
2111 | return matched; | |
2112 | } | |
2113 | ||
b448c4e3 | 2114 | static int |
1cf41dd7 | 2115 | enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int not) |
996e87be | 2116 | { |
b448c4e3 | 2117 | struct ftrace_func_entry *entry; |
b448c4e3 SR |
2118 | int ret = 0; |
2119 | ||
1cf41dd7 SR |
2120 | entry = ftrace_lookup_ip(hash, rec->ip); |
2121 | if (not) { | |
2122 | /* Do nothing if it doesn't exist */ | |
2123 | if (!entry) | |
2124 | return 0; | |
b448c4e3 | 2125 | |
33dc9b12 | 2126 | free_hash_entry(hash, entry); |
1cf41dd7 SR |
2127 | } else { |
2128 | /* Do nothing if it exists */ | |
2129 | if (entry) | |
2130 | return 0; | |
b448c4e3 | 2131 | |
1cf41dd7 | 2132 | ret = add_hash_entry(hash, rec->ip); |
b448c4e3 SR |
2133 | } |
2134 | return ret; | |
996e87be SR |
2135 | } |
2136 | ||
64e7c440 | 2137 | static int |
b9df92d2 SR |
2138 | ftrace_match_record(struct dyn_ftrace *rec, char *mod, |
2139 | char *regex, int len, int type) | |
64e7c440 SR |
2140 | { |
2141 | char str[KSYM_SYMBOL_LEN]; | |
b9df92d2 SR |
2142 | char *modname; |
2143 | ||
2144 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); | |
2145 | ||
2146 | if (mod) { | |
2147 | /* module lookup requires matching the module */ | |
2148 | if (!modname || strcmp(modname, mod)) | |
2149 | return 0; | |
2150 | ||
2151 | /* blank search means to match all funcs in the mod */ | |
2152 | if (!len) | |
2153 | return 1; | |
2154 | } | |
64e7c440 | 2155 | |
64e7c440 SR |
2156 | return ftrace_match(str, regex, len, type); |
2157 | } | |
2158 | ||
1cf41dd7 SR |
2159 | static int |
2160 | match_records(struct ftrace_hash *hash, char *buff, | |
2161 | int len, char *mod, int not) | |
9f4801e3 | 2162 | { |
b9df92d2 | 2163 | unsigned search_len = 0; |
9f4801e3 SR |
2164 | struct ftrace_page *pg; |
2165 | struct dyn_ftrace *rec; | |
b9df92d2 SR |
2166 | int type = MATCH_FULL; |
2167 | char *search = buff; | |
311d16da | 2168 | int found = 0; |
b448c4e3 | 2169 | int ret; |
9f4801e3 | 2170 | |
b9df92d2 SR |
2171 | if (len) { |
2172 | type = filter_parse_regex(buff, len, &search, ¬); | |
2173 | search_len = strlen(search); | |
2174 | } | |
9f4801e3 | 2175 | |
52baf119 | 2176 | mutex_lock(&ftrace_lock); |
265c831c | 2177 | |
b9df92d2 SR |
2178 | if (unlikely(ftrace_disabled)) |
2179 | goto out_unlock; | |
9f4801e3 | 2180 | |
265c831c | 2181 | do_for_each_ftrace_rec(pg, rec) { |
265c831c | 2182 | |
b9df92d2 | 2183 | if (ftrace_match_record(rec, mod, search, search_len, type)) { |
1cf41dd7 | 2184 | ret = enter_record(hash, rec, not); |
b448c4e3 SR |
2185 | if (ret < 0) { |
2186 | found = ret; | |
2187 | goto out_unlock; | |
2188 | } | |
311d16da | 2189 | found = 1; |
265c831c SR |
2190 | } |
2191 | } while_for_each_ftrace_rec(); | |
b9df92d2 | 2192 | out_unlock: |
52baf119 | 2193 | mutex_unlock(&ftrace_lock); |
311d16da LZ |
2194 | |
2195 | return found; | |
5072c59f SR |
2196 | } |
2197 | ||
64e7c440 | 2198 | static int |
1cf41dd7 | 2199 | ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) |
64e7c440 | 2200 | { |
1cf41dd7 | 2201 | return match_records(hash, buff, len, NULL, 0); |
64e7c440 SR |
2202 | } |
2203 | ||
1cf41dd7 SR |
2204 | static int |
2205 | ftrace_match_module_records(struct ftrace_hash *hash, char *buff, char *mod) | |
64e7c440 | 2206 | { |
64e7c440 | 2207 | int not = 0; |
6a24a244 | 2208 | |
64e7c440 SR |
2209 | /* blank or '*' mean the same */ |
2210 | if (strcmp(buff, "*") == 0) | |
2211 | buff[0] = 0; | |
2212 | ||
2213 | /* handle the case of 'dont filter this module' */ | |
2214 | if (strcmp(buff, "!") == 0 || strcmp(buff, "!*") == 0) { | |
2215 | buff[0] = 0; | |
2216 | not = 1; | |
2217 | } | |
2218 | ||
1cf41dd7 | 2219 | return match_records(hash, buff, strlen(buff), mod, not); |
64e7c440 SR |
2220 | } |
2221 | ||
f6180773 SR |
2222 | /* |
2223 | * We register the module command as a template to show others how | |
2224 | * to register the a command as well. | |
2225 | */ | |
2226 | ||
2227 | static int | |
2228 | ftrace_mod_callback(char *func, char *cmd, char *param, int enable) | |
2229 | { | |
f45948e8 | 2230 | struct ftrace_ops *ops = &global_ops; |
1cf41dd7 | 2231 | struct ftrace_hash *hash; |
f6180773 | 2232 | char *mod; |
b448c4e3 | 2233 | int ret = -EINVAL; |
f6180773 SR |
2234 | |
2235 | /* | |
2236 | * cmd == 'mod' because we only registered this func | |
2237 | * for the 'mod' ftrace_func_command. | |
2238 | * But if you register one func with multiple commands, | |
2239 | * you can tell which command was used by the cmd | |
2240 | * parameter. | |
2241 | */ | |
2242 | ||
2243 | /* we must have a module name */ | |
2244 | if (!param) | |
b448c4e3 | 2245 | return ret; |
f6180773 SR |
2246 | |
2247 | mod = strsep(¶m, ":"); | |
2248 | if (!strlen(mod)) | |
b448c4e3 | 2249 | return ret; |
f6180773 | 2250 | |
1cf41dd7 | 2251 | if (enable) |
f45948e8 | 2252 | hash = ops->filter_hash; |
1cf41dd7 | 2253 | else |
f45948e8 | 2254 | hash = ops->notrace_hash; |
1cf41dd7 SR |
2255 | |
2256 | ret = ftrace_match_module_records(hash, func, mod); | |
b448c4e3 SR |
2257 | if (!ret) |
2258 | ret = -EINVAL; | |
2259 | if (ret < 0) | |
2260 | return ret; | |
2261 | ||
2262 | return 0; | |
f6180773 SR |
2263 | } |
2264 | ||
2265 | static struct ftrace_func_command ftrace_mod_cmd = { | |
2266 | .name = "mod", | |
2267 | .func = ftrace_mod_callback, | |
2268 | }; | |
2269 | ||
2270 | static int __init ftrace_mod_cmd_init(void) | |
2271 | { | |
2272 | return register_ftrace_command(&ftrace_mod_cmd); | |
2273 | } | |
2274 | device_initcall(ftrace_mod_cmd_init); | |
2275 | ||
59df055f | 2276 | static void |
b6887d79 | 2277 | function_trace_probe_call(unsigned long ip, unsigned long parent_ip) |
59df055f | 2278 | { |
b6887d79 | 2279 | struct ftrace_func_probe *entry; |
59df055f SR |
2280 | struct hlist_head *hhd; |
2281 | struct hlist_node *n; | |
2282 | unsigned long key; | |
59df055f SR |
2283 | |
2284 | key = hash_long(ip, FTRACE_HASH_BITS); | |
2285 | ||
2286 | hhd = &ftrace_func_hash[key]; | |
2287 | ||
2288 | if (hlist_empty(hhd)) | |
2289 | return; | |
2290 | ||
2291 | /* | |
2292 | * Disable preemption for these calls to prevent a RCU grace | |
2293 | * period. This syncs the hash iteration and freeing of items | |
2294 | * on the hash. rcu_read_lock is too dangerous here. | |
2295 | */ | |
5168ae50 | 2296 | preempt_disable_notrace(); |
59df055f SR |
2297 | hlist_for_each_entry_rcu(entry, n, hhd, node) { |
2298 | if (entry->ip == ip) | |
2299 | entry->ops->func(ip, parent_ip, &entry->data); | |
2300 | } | |
5168ae50 | 2301 | preempt_enable_notrace(); |
59df055f SR |
2302 | } |
2303 | ||
b6887d79 | 2304 | static struct ftrace_ops trace_probe_ops __read_mostly = |
59df055f | 2305 | { |
fb9fb015 | 2306 | .func = function_trace_probe_call, |
59df055f SR |
2307 | }; |
2308 | ||
b6887d79 | 2309 | static int ftrace_probe_registered; |
59df055f | 2310 | |
b6887d79 | 2311 | static void __enable_ftrace_function_probe(void) |
59df055f SR |
2312 | { |
2313 | int i; | |
2314 | ||
b6887d79 | 2315 | if (ftrace_probe_registered) |
59df055f SR |
2316 | return; |
2317 | ||
2318 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
2319 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
2320 | if (hhd->first) | |
2321 | break; | |
2322 | } | |
2323 | /* Nothing registered? */ | |
2324 | if (i == FTRACE_FUNC_HASHSIZE) | |
2325 | return; | |
2326 | ||
b6887d79 | 2327 | __register_ftrace_function(&trace_probe_ops); |
59df055f | 2328 | ftrace_startup(0); |
b6887d79 | 2329 | ftrace_probe_registered = 1; |
59df055f SR |
2330 | } |
2331 | ||
b6887d79 | 2332 | static void __disable_ftrace_function_probe(void) |
59df055f SR |
2333 | { |
2334 | int i; | |
2335 | ||
b6887d79 | 2336 | if (!ftrace_probe_registered) |
59df055f SR |
2337 | return; |
2338 | ||
2339 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
2340 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
2341 | if (hhd->first) | |
2342 | return; | |
2343 | } | |
2344 | ||
2345 | /* no more funcs left */ | |
b6887d79 | 2346 | __unregister_ftrace_function(&trace_probe_ops); |
59df055f | 2347 | ftrace_shutdown(0); |
b6887d79 | 2348 | ftrace_probe_registered = 0; |
59df055f SR |
2349 | } |
2350 | ||
2351 | ||
2352 | static void ftrace_free_entry_rcu(struct rcu_head *rhp) | |
2353 | { | |
b6887d79 SR |
2354 | struct ftrace_func_probe *entry = |
2355 | container_of(rhp, struct ftrace_func_probe, rcu); | |
59df055f SR |
2356 | |
2357 | if (entry->ops->free) | |
2358 | entry->ops->free(&entry->data); | |
2359 | kfree(entry); | |
2360 | } | |
2361 | ||
2362 | ||
2363 | int | |
b6887d79 | 2364 | register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
2365 | void *data) |
2366 | { | |
b6887d79 | 2367 | struct ftrace_func_probe *entry; |
59df055f SR |
2368 | struct ftrace_page *pg; |
2369 | struct dyn_ftrace *rec; | |
59df055f | 2370 | int type, len, not; |
6a24a244 | 2371 | unsigned long key; |
59df055f SR |
2372 | int count = 0; |
2373 | char *search; | |
2374 | ||
3f6fe06d | 2375 | type = filter_parse_regex(glob, strlen(glob), &search, ¬); |
59df055f SR |
2376 | len = strlen(search); |
2377 | ||
b6887d79 | 2378 | /* we do not support '!' for function probes */ |
59df055f SR |
2379 | if (WARN_ON(not)) |
2380 | return -EINVAL; | |
2381 | ||
2382 | mutex_lock(&ftrace_lock); | |
59df055f | 2383 | |
45a4a237 SR |
2384 | if (unlikely(ftrace_disabled)) |
2385 | goto out_unlock; | |
59df055f | 2386 | |
45a4a237 | 2387 | do_for_each_ftrace_rec(pg, rec) { |
59df055f | 2388 | |
b9df92d2 | 2389 | if (!ftrace_match_record(rec, NULL, search, len, type)) |
59df055f SR |
2390 | continue; |
2391 | ||
2392 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
2393 | if (!entry) { | |
b6887d79 | 2394 | /* If we did not process any, then return error */ |
59df055f SR |
2395 | if (!count) |
2396 | count = -ENOMEM; | |
2397 | goto out_unlock; | |
2398 | } | |
2399 | ||
2400 | count++; | |
2401 | ||
2402 | entry->data = data; | |
2403 | ||
2404 | /* | |
2405 | * The caller might want to do something special | |
2406 | * for each function we find. We call the callback | |
2407 | * to give the caller an opportunity to do so. | |
2408 | */ | |
2409 | if (ops->callback) { | |
2410 | if (ops->callback(rec->ip, &entry->data) < 0) { | |
2411 | /* caller does not like this func */ | |
2412 | kfree(entry); | |
2413 | continue; | |
2414 | } | |
2415 | } | |
2416 | ||
2417 | entry->ops = ops; | |
2418 | entry->ip = rec->ip; | |
2419 | ||
2420 | key = hash_long(entry->ip, FTRACE_HASH_BITS); | |
2421 | hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]); | |
2422 | ||
2423 | } while_for_each_ftrace_rec(); | |
b6887d79 | 2424 | __enable_ftrace_function_probe(); |
59df055f SR |
2425 | |
2426 | out_unlock: | |
2427 | mutex_unlock(&ftrace_lock); | |
2428 | ||
2429 | return count; | |
2430 | } | |
2431 | ||
2432 | enum { | |
b6887d79 SR |
2433 | PROBE_TEST_FUNC = 1, |
2434 | PROBE_TEST_DATA = 2 | |
59df055f SR |
2435 | }; |
2436 | ||
2437 | static void | |
b6887d79 | 2438 | __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
2439 | void *data, int flags) |
2440 | { | |
b6887d79 | 2441 | struct ftrace_func_probe *entry; |
59df055f SR |
2442 | struct hlist_node *n, *tmp; |
2443 | char str[KSYM_SYMBOL_LEN]; | |
2444 | int type = MATCH_FULL; | |
2445 | int i, len = 0; | |
2446 | char *search; | |
2447 | ||
b36461da | 2448 | if (glob && (strcmp(glob, "*") == 0 || !strlen(glob))) |
59df055f | 2449 | glob = NULL; |
b36461da | 2450 | else if (glob) { |
59df055f SR |
2451 | int not; |
2452 | ||
3f6fe06d | 2453 | type = filter_parse_regex(glob, strlen(glob), &search, ¬); |
59df055f SR |
2454 | len = strlen(search); |
2455 | ||
b6887d79 | 2456 | /* we do not support '!' for function probes */ |
59df055f SR |
2457 | if (WARN_ON(not)) |
2458 | return; | |
2459 | } | |
2460 | ||
2461 | mutex_lock(&ftrace_lock); | |
2462 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
2463 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
2464 | ||
2465 | hlist_for_each_entry_safe(entry, n, tmp, hhd, node) { | |
2466 | ||
2467 | /* break up if statements for readability */ | |
b6887d79 | 2468 | if ((flags & PROBE_TEST_FUNC) && entry->ops != ops) |
59df055f SR |
2469 | continue; |
2470 | ||
b6887d79 | 2471 | if ((flags & PROBE_TEST_DATA) && entry->data != data) |
59df055f SR |
2472 | continue; |
2473 | ||
2474 | /* do this last, since it is the most expensive */ | |
2475 | if (glob) { | |
2476 | kallsyms_lookup(entry->ip, NULL, NULL, | |
2477 | NULL, str); | |
2478 | if (!ftrace_match(str, glob, len, type)) | |
2479 | continue; | |
2480 | } | |
2481 | ||
2482 | hlist_del(&entry->node); | |
2483 | call_rcu(&entry->rcu, ftrace_free_entry_rcu); | |
2484 | } | |
2485 | } | |
b6887d79 | 2486 | __disable_ftrace_function_probe(); |
59df055f SR |
2487 | mutex_unlock(&ftrace_lock); |
2488 | } | |
2489 | ||
2490 | void | |
b6887d79 | 2491 | unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
2492 | void *data) |
2493 | { | |
b6887d79 SR |
2494 | __unregister_ftrace_function_probe(glob, ops, data, |
2495 | PROBE_TEST_FUNC | PROBE_TEST_DATA); | |
59df055f SR |
2496 | } |
2497 | ||
2498 | void | |
b6887d79 | 2499 | unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops) |
59df055f | 2500 | { |
b6887d79 | 2501 | __unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC); |
59df055f SR |
2502 | } |
2503 | ||
b6887d79 | 2504 | void unregister_ftrace_function_probe_all(char *glob) |
59df055f | 2505 | { |
b6887d79 | 2506 | __unregister_ftrace_function_probe(glob, NULL, NULL, 0); |
59df055f SR |
2507 | } |
2508 | ||
f6180773 SR |
2509 | static LIST_HEAD(ftrace_commands); |
2510 | static DEFINE_MUTEX(ftrace_cmd_mutex); | |
2511 | ||
2512 | int register_ftrace_command(struct ftrace_func_command *cmd) | |
2513 | { | |
2514 | struct ftrace_func_command *p; | |
2515 | int ret = 0; | |
2516 | ||
2517 | mutex_lock(&ftrace_cmd_mutex); | |
2518 | list_for_each_entry(p, &ftrace_commands, list) { | |
2519 | if (strcmp(cmd->name, p->name) == 0) { | |
2520 | ret = -EBUSY; | |
2521 | goto out_unlock; | |
2522 | } | |
2523 | } | |
2524 | list_add(&cmd->list, &ftrace_commands); | |
2525 | out_unlock: | |
2526 | mutex_unlock(&ftrace_cmd_mutex); | |
2527 | ||
2528 | return ret; | |
2529 | } | |
2530 | ||
2531 | int unregister_ftrace_command(struct ftrace_func_command *cmd) | |
2532 | { | |
2533 | struct ftrace_func_command *p, *n; | |
2534 | int ret = -ENODEV; | |
2535 | ||
2536 | mutex_lock(&ftrace_cmd_mutex); | |
2537 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { | |
2538 | if (strcmp(cmd->name, p->name) == 0) { | |
2539 | ret = 0; | |
2540 | list_del_init(&p->list); | |
2541 | goto out_unlock; | |
2542 | } | |
2543 | } | |
2544 | out_unlock: | |
2545 | mutex_unlock(&ftrace_cmd_mutex); | |
2546 | ||
2547 | return ret; | |
2548 | } | |
2549 | ||
33dc9b12 SR |
2550 | static int ftrace_process_regex(struct ftrace_hash *hash, |
2551 | char *buff, int len, int enable) | |
64e7c440 | 2552 | { |
f6180773 | 2553 | char *func, *command, *next = buff; |
6a24a244 | 2554 | struct ftrace_func_command *p; |
b448c4e3 | 2555 | int ret; |
64e7c440 SR |
2556 | |
2557 | func = strsep(&next, ":"); | |
2558 | ||
2559 | if (!next) { | |
1cf41dd7 | 2560 | ret = ftrace_match_records(hash, func, len); |
b448c4e3 SR |
2561 | if (!ret) |
2562 | ret = -EINVAL; | |
2563 | if (ret < 0) | |
2564 | return ret; | |
2565 | return 0; | |
64e7c440 SR |
2566 | } |
2567 | ||
f6180773 | 2568 | /* command found */ |
64e7c440 SR |
2569 | |
2570 | command = strsep(&next, ":"); | |
2571 | ||
f6180773 SR |
2572 | mutex_lock(&ftrace_cmd_mutex); |
2573 | list_for_each_entry(p, &ftrace_commands, list) { | |
2574 | if (strcmp(p->name, command) == 0) { | |
2575 | ret = p->func(func, command, next, enable); | |
2576 | goto out_unlock; | |
2577 | } | |
64e7c440 | 2578 | } |
f6180773 SR |
2579 | out_unlock: |
2580 | mutex_unlock(&ftrace_cmd_mutex); | |
64e7c440 | 2581 | |
f6180773 | 2582 | return ret; |
64e7c440 SR |
2583 | } |
2584 | ||
e309b41d | 2585 | static ssize_t |
41c52c0d SR |
2586 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
2587 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
2588 | { |
2589 | struct ftrace_iterator *iter; | |
689fd8b6 | 2590 | struct trace_parser *parser; |
2591 | ssize_t ret, read; | |
5072c59f | 2592 | |
4ba7978e | 2593 | if (!cnt) |
5072c59f SR |
2594 | return 0; |
2595 | ||
41c52c0d | 2596 | mutex_lock(&ftrace_regex_lock); |
5072c59f | 2597 | |
45a4a237 SR |
2598 | ret = -ENODEV; |
2599 | if (unlikely(ftrace_disabled)) | |
2600 | goto out_unlock; | |
2601 | ||
5072c59f SR |
2602 | if (file->f_mode & FMODE_READ) { |
2603 | struct seq_file *m = file->private_data; | |
2604 | iter = m->private; | |
2605 | } else | |
2606 | iter = file->private_data; | |
2607 | ||
689fd8b6 | 2608 | parser = &iter->parser; |
2609 | read = trace_get_user(parser, ubuf, cnt, ppos); | |
5072c59f | 2610 | |
4ba7978e | 2611 | if (read >= 0 && trace_parser_loaded(parser) && |
689fd8b6 | 2612 | !trace_parser_cont(parser)) { |
33dc9b12 | 2613 | ret = ftrace_process_regex(iter->hash, parser->buffer, |
689fd8b6 | 2614 | parser->idx, enable); |
313254a9 | 2615 | trace_parser_clear(parser); |
5072c59f | 2616 | if (ret) |
ed146b25 | 2617 | goto out_unlock; |
eda1e328 | 2618 | } |
5072c59f | 2619 | |
5072c59f | 2620 | ret = read; |
ed146b25 | 2621 | out_unlock: |
689fd8b6 | 2622 | mutex_unlock(&ftrace_regex_lock); |
ed146b25 | 2623 | |
5072c59f SR |
2624 | return ret; |
2625 | } | |
2626 | ||
41c52c0d SR |
2627 | static ssize_t |
2628 | ftrace_filter_write(struct file *file, const char __user *ubuf, | |
2629 | size_t cnt, loff_t *ppos) | |
2630 | { | |
2631 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
2632 | } | |
2633 | ||
2634 | static ssize_t | |
2635 | ftrace_notrace_write(struct file *file, const char __user *ubuf, | |
2636 | size_t cnt, loff_t *ppos) | |
2637 | { | |
2638 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
2639 | } | |
2640 | ||
33dc9b12 | 2641 | static int |
f45948e8 SR |
2642 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, |
2643 | int reset, int enable) | |
41c52c0d | 2644 | { |
33dc9b12 | 2645 | struct ftrace_hash **orig_hash; |
f45948e8 | 2646 | struct ftrace_hash *hash; |
33dc9b12 | 2647 | int ret; |
f45948e8 | 2648 | |
41c52c0d | 2649 | if (unlikely(ftrace_disabled)) |
33dc9b12 | 2650 | return -ENODEV; |
41c52c0d | 2651 | |
f45948e8 | 2652 | if (enable) |
33dc9b12 | 2653 | orig_hash = &ops->filter_hash; |
f45948e8 | 2654 | else |
33dc9b12 SR |
2655 | orig_hash = &ops->notrace_hash; |
2656 | ||
2657 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
2658 | if (!hash) | |
2659 | return -ENOMEM; | |
f45948e8 | 2660 | |
41c52c0d SR |
2661 | mutex_lock(&ftrace_regex_lock); |
2662 | if (reset) | |
1cf41dd7 | 2663 | ftrace_filter_reset(hash); |
41c52c0d | 2664 | if (buf) |
1cf41dd7 | 2665 | ftrace_match_records(hash, buf, len); |
33dc9b12 SR |
2666 | |
2667 | mutex_lock(&ftrace_lock); | |
2668 | ret = ftrace_hash_move(orig_hash, hash); | |
2669 | mutex_unlock(&ftrace_lock); | |
2670 | ||
41c52c0d | 2671 | mutex_unlock(&ftrace_regex_lock); |
33dc9b12 SR |
2672 | |
2673 | free_ftrace_hash(hash); | |
2674 | return ret; | |
41c52c0d SR |
2675 | } |
2676 | ||
77a2b37d SR |
2677 | /** |
2678 | * ftrace_set_filter - set a function to filter on in ftrace | |
2679 | * @buf - the string that holds the function filter text. | |
2680 | * @len - the length of the string. | |
2681 | * @reset - non zero to reset all filters before applying this filter. | |
2682 | * | |
2683 | * Filters denote which functions should be enabled when tracing is enabled. | |
2684 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
2685 | */ | |
e309b41d | 2686 | void ftrace_set_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 2687 | { |
f45948e8 | 2688 | ftrace_set_regex(&global_ops, buf, len, reset, 1); |
41c52c0d | 2689 | } |
4eebcc81 | 2690 | |
41c52c0d SR |
2691 | /** |
2692 | * ftrace_set_notrace - set a function to not trace in ftrace | |
2693 | * @buf - the string that holds the function notrace text. | |
2694 | * @len - the length of the string. | |
2695 | * @reset - non zero to reset all filters before applying this filter. | |
2696 | * | |
2697 | * Notrace Filters denote which functions should not be enabled when tracing | |
2698 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
2699 | * for tracing. | |
2700 | */ | |
2701 | void ftrace_set_notrace(unsigned char *buf, int len, int reset) | |
2702 | { | |
f45948e8 | 2703 | ftrace_set_regex(&global_ops, buf, len, reset, 0); |
77a2b37d SR |
2704 | } |
2705 | ||
2af15d6a SR |
2706 | /* |
2707 | * command line interface to allow users to set filters on boot up. | |
2708 | */ | |
2709 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE | |
2710 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; | |
2711 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; | |
2712 | ||
2713 | static int __init set_ftrace_notrace(char *str) | |
2714 | { | |
2715 | strncpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); | |
2716 | return 1; | |
2717 | } | |
2718 | __setup("ftrace_notrace=", set_ftrace_notrace); | |
2719 | ||
2720 | static int __init set_ftrace_filter(char *str) | |
2721 | { | |
2722 | strncpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); | |
2723 | return 1; | |
2724 | } | |
2725 | __setup("ftrace_filter=", set_ftrace_filter); | |
2726 | ||
369bc18f | 2727 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
f6060f46 | 2728 | static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; |
801c29fd SR |
2729 | static int ftrace_set_func(unsigned long *array, int *idx, char *buffer); |
2730 | ||
369bc18f SA |
2731 | static int __init set_graph_function(char *str) |
2732 | { | |
06f43d66 | 2733 | strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); |
369bc18f SA |
2734 | return 1; |
2735 | } | |
2736 | __setup("ftrace_graph_filter=", set_graph_function); | |
2737 | ||
2738 | static void __init set_ftrace_early_graph(char *buf) | |
2739 | { | |
2740 | int ret; | |
2741 | char *func; | |
2742 | ||
2743 | while (buf) { | |
2744 | func = strsep(&buf, ","); | |
2745 | /* we allow only one expression at a time */ | |
2746 | ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, | |
2747 | func); | |
2748 | if (ret) | |
2749 | printk(KERN_DEBUG "ftrace: function %s not " | |
2750 | "traceable\n", func); | |
2751 | } | |
2752 | } | |
2753 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
2754 | ||
f45948e8 SR |
2755 | static void __init |
2756 | set_ftrace_early_filter(struct ftrace_ops *ops, char *buf, int enable) | |
2af15d6a SR |
2757 | { |
2758 | char *func; | |
2759 | ||
2760 | while (buf) { | |
2761 | func = strsep(&buf, ","); | |
f45948e8 | 2762 | ftrace_set_regex(ops, func, strlen(func), 0, enable); |
2af15d6a SR |
2763 | } |
2764 | } | |
2765 | ||
2766 | static void __init set_ftrace_early_filters(void) | |
2767 | { | |
2768 | if (ftrace_filter_buf[0]) | |
f45948e8 | 2769 | set_ftrace_early_filter(&global_ops, ftrace_filter_buf, 1); |
2af15d6a | 2770 | if (ftrace_notrace_buf[0]) |
f45948e8 | 2771 | set_ftrace_early_filter(&global_ops, ftrace_notrace_buf, 0); |
369bc18f SA |
2772 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
2773 | if (ftrace_graph_buf[0]) | |
2774 | set_ftrace_early_graph(ftrace_graph_buf); | |
2775 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
2af15d6a SR |
2776 | } |
2777 | ||
e309b41d | 2778 | static int |
1cf41dd7 | 2779 | ftrace_regex_release(struct inode *inode, struct file *file) |
5072c59f SR |
2780 | { |
2781 | struct seq_file *m = (struct seq_file *)file->private_data; | |
2782 | struct ftrace_iterator *iter; | |
33dc9b12 | 2783 | struct ftrace_hash **orig_hash; |
689fd8b6 | 2784 | struct trace_parser *parser; |
ed926f9b | 2785 | int filter_hash; |
33dc9b12 | 2786 | int ret; |
5072c59f | 2787 | |
41c52c0d | 2788 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
2789 | if (file->f_mode & FMODE_READ) { |
2790 | iter = m->private; | |
2791 | ||
2792 | seq_release(inode, file); | |
2793 | } else | |
2794 | iter = file->private_data; | |
2795 | ||
689fd8b6 | 2796 | parser = &iter->parser; |
2797 | if (trace_parser_loaded(parser)) { | |
2798 | parser->buffer[parser->idx] = 0; | |
1cf41dd7 | 2799 | ftrace_match_records(iter->hash, parser->buffer, parser->idx); |
5072c59f SR |
2800 | } |
2801 | ||
689fd8b6 | 2802 | trace_parser_put(parser); |
689fd8b6 | 2803 | |
058e297d | 2804 | if (file->f_mode & FMODE_WRITE) { |
ed926f9b SR |
2805 | filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); |
2806 | ||
2807 | if (filter_hash) | |
33dc9b12 | 2808 | orig_hash = &iter->ops->filter_hash; |
ed926f9b SR |
2809 | else |
2810 | orig_hash = &iter->ops->notrace_hash; | |
33dc9b12 | 2811 | |
058e297d | 2812 | mutex_lock(&ftrace_lock); |
ed926f9b SR |
2813 | /* |
2814 | * Remove the current set, update the hash and add | |
2815 | * them back. | |
2816 | */ | |
2817 | ftrace_hash_rec_disable(iter->ops, filter_hash); | |
33dc9b12 | 2818 | ret = ftrace_hash_move(orig_hash, iter->hash); |
ed926f9b SR |
2819 | if (!ret) { |
2820 | ftrace_hash_rec_enable(iter->ops, filter_hash); | |
2821 | if (iter->ops->flags & FTRACE_OPS_FL_ENABLED | |
2822 | && ftrace_enabled) | |
2823 | ftrace_run_update_code(FTRACE_ENABLE_CALLS); | |
2824 | } | |
058e297d SR |
2825 | mutex_unlock(&ftrace_lock); |
2826 | } | |
33dc9b12 SR |
2827 | free_ftrace_hash(iter->hash); |
2828 | kfree(iter); | |
058e297d | 2829 | |
41c52c0d | 2830 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
2831 | return 0; |
2832 | } | |
2833 | ||
5e2336a0 | 2834 | static const struct file_operations ftrace_avail_fops = { |
5072c59f SR |
2835 | .open = ftrace_avail_open, |
2836 | .read = seq_read, | |
2837 | .llseek = seq_lseek, | |
3be04b47 | 2838 | .release = seq_release_private, |
5072c59f SR |
2839 | }; |
2840 | ||
5e2336a0 | 2841 | static const struct file_operations ftrace_filter_fops = { |
5072c59f | 2842 | .open = ftrace_filter_open, |
850a80cf | 2843 | .read = seq_read, |
5072c59f | 2844 | .write = ftrace_filter_write, |
98c4fd04 | 2845 | .llseek = ftrace_regex_lseek, |
1cf41dd7 | 2846 | .release = ftrace_regex_release, |
5072c59f SR |
2847 | }; |
2848 | ||
5e2336a0 | 2849 | static const struct file_operations ftrace_notrace_fops = { |
41c52c0d | 2850 | .open = ftrace_notrace_open, |
850a80cf | 2851 | .read = seq_read, |
41c52c0d SR |
2852 | .write = ftrace_notrace_write, |
2853 | .llseek = ftrace_regex_lseek, | |
1cf41dd7 | 2854 | .release = ftrace_regex_release, |
41c52c0d SR |
2855 | }; |
2856 | ||
ea4e2bc4 SR |
2857 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
2858 | ||
2859 | static DEFINE_MUTEX(graph_lock); | |
2860 | ||
2861 | int ftrace_graph_count; | |
c7c6b1fe | 2862 | int ftrace_graph_filter_enabled; |
ea4e2bc4 SR |
2863 | unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; |
2864 | ||
2865 | static void * | |
85951842 | 2866 | __g_next(struct seq_file *m, loff_t *pos) |
ea4e2bc4 | 2867 | { |
85951842 | 2868 | if (*pos >= ftrace_graph_count) |
ea4e2bc4 | 2869 | return NULL; |
a4ec5e0c | 2870 | return &ftrace_graph_funcs[*pos]; |
85951842 | 2871 | } |
ea4e2bc4 | 2872 | |
85951842 LZ |
2873 | static void * |
2874 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
2875 | { | |
2876 | (*pos)++; | |
2877 | return __g_next(m, pos); | |
ea4e2bc4 SR |
2878 | } |
2879 | ||
2880 | static void *g_start(struct seq_file *m, loff_t *pos) | |
2881 | { | |
ea4e2bc4 SR |
2882 | mutex_lock(&graph_lock); |
2883 | ||
f9349a8f | 2884 | /* Nothing, tell g_show to print all functions are enabled */ |
c7c6b1fe | 2885 | if (!ftrace_graph_filter_enabled && !*pos) |
f9349a8f FW |
2886 | return (void *)1; |
2887 | ||
85951842 | 2888 | return __g_next(m, pos); |
ea4e2bc4 SR |
2889 | } |
2890 | ||
2891 | static void g_stop(struct seq_file *m, void *p) | |
2892 | { | |
2893 | mutex_unlock(&graph_lock); | |
2894 | } | |
2895 | ||
2896 | static int g_show(struct seq_file *m, void *v) | |
2897 | { | |
2898 | unsigned long *ptr = v; | |
ea4e2bc4 SR |
2899 | |
2900 | if (!ptr) | |
2901 | return 0; | |
2902 | ||
f9349a8f FW |
2903 | if (ptr == (unsigned long *)1) { |
2904 | seq_printf(m, "#### all functions enabled ####\n"); | |
2905 | return 0; | |
2906 | } | |
2907 | ||
b375a11a | 2908 | seq_printf(m, "%ps\n", (void *)*ptr); |
ea4e2bc4 SR |
2909 | |
2910 | return 0; | |
2911 | } | |
2912 | ||
88e9d34c | 2913 | static const struct seq_operations ftrace_graph_seq_ops = { |
ea4e2bc4 SR |
2914 | .start = g_start, |
2915 | .next = g_next, | |
2916 | .stop = g_stop, | |
2917 | .show = g_show, | |
2918 | }; | |
2919 | ||
2920 | static int | |
2921 | ftrace_graph_open(struct inode *inode, struct file *file) | |
2922 | { | |
2923 | int ret = 0; | |
2924 | ||
2925 | if (unlikely(ftrace_disabled)) | |
2926 | return -ENODEV; | |
2927 | ||
2928 | mutex_lock(&graph_lock); | |
2929 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2930 | (file->f_flags & O_TRUNC)) { |
c7c6b1fe | 2931 | ftrace_graph_filter_enabled = 0; |
ea4e2bc4 SR |
2932 | ftrace_graph_count = 0; |
2933 | memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); | |
2934 | } | |
a4ec5e0c | 2935 | mutex_unlock(&graph_lock); |
ea4e2bc4 | 2936 | |
a4ec5e0c | 2937 | if (file->f_mode & FMODE_READ) |
ea4e2bc4 | 2938 | ret = seq_open(file, &ftrace_graph_seq_ops); |
ea4e2bc4 SR |
2939 | |
2940 | return ret; | |
2941 | } | |
2942 | ||
87827111 LZ |
2943 | static int |
2944 | ftrace_graph_release(struct inode *inode, struct file *file) | |
2945 | { | |
2946 | if (file->f_mode & FMODE_READ) | |
2947 | seq_release(inode, file); | |
2948 | return 0; | |
2949 | } | |
2950 | ||
ea4e2bc4 | 2951 | static int |
f9349a8f | 2952 | ftrace_set_func(unsigned long *array, int *idx, char *buffer) |
ea4e2bc4 | 2953 | { |
ea4e2bc4 SR |
2954 | struct dyn_ftrace *rec; |
2955 | struct ftrace_page *pg; | |
f9349a8f | 2956 | int search_len; |
c7c6b1fe | 2957 | int fail = 1; |
f9349a8f FW |
2958 | int type, not; |
2959 | char *search; | |
2960 | bool exists; | |
2961 | int i; | |
ea4e2bc4 | 2962 | |
f9349a8f | 2963 | /* decode regex */ |
3f6fe06d | 2964 | type = filter_parse_regex(buffer, strlen(buffer), &search, ¬); |
c7c6b1fe LZ |
2965 | if (!not && *idx >= FTRACE_GRAPH_MAX_FUNCS) |
2966 | return -EBUSY; | |
f9349a8f FW |
2967 | |
2968 | search_len = strlen(search); | |
2969 | ||
52baf119 | 2970 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
2971 | |
2972 | if (unlikely(ftrace_disabled)) { | |
2973 | mutex_unlock(&ftrace_lock); | |
2974 | return -ENODEV; | |
2975 | } | |
2976 | ||
265c831c SR |
2977 | do_for_each_ftrace_rec(pg, rec) { |
2978 | ||
45a4a237 | 2979 | if (rec->flags & FTRACE_FL_FREE) |
265c831c SR |
2980 | continue; |
2981 | ||
b9df92d2 | 2982 | if (ftrace_match_record(rec, NULL, search, search_len, type)) { |
c7c6b1fe | 2983 | /* if it is in the array */ |
f9349a8f | 2984 | exists = false; |
c7c6b1fe | 2985 | for (i = 0; i < *idx; i++) { |
f9349a8f FW |
2986 | if (array[i] == rec->ip) { |
2987 | exists = true; | |
265c831c SR |
2988 | break; |
2989 | } | |
c7c6b1fe LZ |
2990 | } |
2991 | ||
2992 | if (!not) { | |
2993 | fail = 0; | |
2994 | if (!exists) { | |
2995 | array[(*idx)++] = rec->ip; | |
2996 | if (*idx >= FTRACE_GRAPH_MAX_FUNCS) | |
2997 | goto out; | |
2998 | } | |
2999 | } else { | |
3000 | if (exists) { | |
3001 | array[i] = array[--(*idx)]; | |
3002 | array[*idx] = 0; | |
3003 | fail = 0; | |
3004 | } | |
3005 | } | |
ea4e2bc4 | 3006 | } |
265c831c | 3007 | } while_for_each_ftrace_rec(); |
c7c6b1fe | 3008 | out: |
52baf119 | 3009 | mutex_unlock(&ftrace_lock); |
ea4e2bc4 | 3010 | |
c7c6b1fe LZ |
3011 | if (fail) |
3012 | return -EINVAL; | |
3013 | ||
3014 | ftrace_graph_filter_enabled = 1; | |
3015 | return 0; | |
ea4e2bc4 SR |
3016 | } |
3017 | ||
3018 | static ssize_t | |
3019 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
3020 | size_t cnt, loff_t *ppos) | |
3021 | { | |
689fd8b6 | 3022 | struct trace_parser parser; |
4ba7978e | 3023 | ssize_t read, ret; |
ea4e2bc4 | 3024 | |
c7c6b1fe | 3025 | if (!cnt) |
ea4e2bc4 SR |
3026 | return 0; |
3027 | ||
3028 | mutex_lock(&graph_lock); | |
3029 | ||
689fd8b6 | 3030 | if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) { |
3031 | ret = -ENOMEM; | |
1eb90f13 | 3032 | goto out_unlock; |
ea4e2bc4 SR |
3033 | } |
3034 | ||
689fd8b6 | 3035 | read = trace_get_user(&parser, ubuf, cnt, ppos); |
ea4e2bc4 | 3036 | |
4ba7978e | 3037 | if (read >= 0 && trace_parser_loaded((&parser))) { |
689fd8b6 | 3038 | parser.buffer[parser.idx] = 0; |
3039 | ||
3040 | /* we allow only one expression at a time */ | |
a4ec5e0c | 3041 | ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, |
689fd8b6 | 3042 | parser.buffer); |
ea4e2bc4 | 3043 | if (ret) |
1eb90f13 | 3044 | goto out_free; |
ea4e2bc4 | 3045 | } |
ea4e2bc4 SR |
3046 | |
3047 | ret = read; | |
1eb90f13 LZ |
3048 | |
3049 | out_free: | |
689fd8b6 | 3050 | trace_parser_put(&parser); |
1eb90f13 | 3051 | out_unlock: |
ea4e2bc4 SR |
3052 | mutex_unlock(&graph_lock); |
3053 | ||
3054 | return ret; | |
3055 | } | |
3056 | ||
3057 | static const struct file_operations ftrace_graph_fops = { | |
87827111 LZ |
3058 | .open = ftrace_graph_open, |
3059 | .read = seq_read, | |
3060 | .write = ftrace_graph_write, | |
3061 | .release = ftrace_graph_release, | |
6038f373 | 3062 | .llseek = seq_lseek, |
ea4e2bc4 SR |
3063 | }; |
3064 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
3065 | ||
df4fc315 | 3066 | static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) |
5072c59f | 3067 | { |
5072c59f | 3068 | |
5452af66 FW |
3069 | trace_create_file("available_filter_functions", 0444, |
3070 | d_tracer, NULL, &ftrace_avail_fops); | |
5072c59f | 3071 | |
5452af66 FW |
3072 | trace_create_file("set_ftrace_filter", 0644, d_tracer, |
3073 | NULL, &ftrace_filter_fops); | |
41c52c0d | 3074 | |
5452af66 | 3075 | trace_create_file("set_ftrace_notrace", 0644, d_tracer, |
41c52c0d | 3076 | NULL, &ftrace_notrace_fops); |
ad90c0e3 | 3077 | |
ea4e2bc4 | 3078 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5452af66 | 3079 | trace_create_file("set_graph_function", 0444, d_tracer, |
ea4e2bc4 SR |
3080 | NULL, |
3081 | &ftrace_graph_fops); | |
ea4e2bc4 SR |
3082 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
3083 | ||
5072c59f SR |
3084 | return 0; |
3085 | } | |
3086 | ||
5cb084bb | 3087 | static int ftrace_process_locs(struct module *mod, |
31e88909 | 3088 | unsigned long *start, |
68bf21aa SR |
3089 | unsigned long *end) |
3090 | { | |
3091 | unsigned long *p; | |
3092 | unsigned long addr; | |
68bf21aa | 3093 | |
e6ea44e9 | 3094 | mutex_lock(&ftrace_lock); |
68bf21aa SR |
3095 | p = start; |
3096 | while (p < end) { | |
3097 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
3098 | /* |
3099 | * Some architecture linkers will pad between | |
3100 | * the different mcount_loc sections of different | |
3101 | * object files to satisfy alignments. | |
3102 | * Skip any NULL pointers. | |
3103 | */ | |
3104 | if (!addr) | |
3105 | continue; | |
68bf21aa | 3106 | ftrace_record_ip(addr); |
68bf21aa SR |
3107 | } |
3108 | ||
31e88909 | 3109 | ftrace_update_code(mod); |
e6ea44e9 | 3110 | mutex_unlock(&ftrace_lock); |
68bf21aa SR |
3111 | |
3112 | return 0; | |
3113 | } | |
3114 | ||
93eb677d | 3115 | #ifdef CONFIG_MODULES |
e7247a15 | 3116 | void ftrace_release_mod(struct module *mod) |
93eb677d SR |
3117 | { |
3118 | struct dyn_ftrace *rec; | |
3119 | struct ftrace_page *pg; | |
93eb677d | 3120 | |
45a4a237 SR |
3121 | mutex_lock(&ftrace_lock); |
3122 | ||
e7247a15 | 3123 | if (ftrace_disabled) |
45a4a237 | 3124 | goto out_unlock; |
93eb677d | 3125 | |
93eb677d | 3126 | do_for_each_ftrace_rec(pg, rec) { |
e7247a15 | 3127 | if (within_module_core(rec->ip, mod)) { |
93eb677d SR |
3128 | /* |
3129 | * rec->ip is changed in ftrace_free_rec() | |
3130 | * It should not between s and e if record was freed. | |
3131 | */ | |
3132 | FTRACE_WARN_ON(rec->flags & FTRACE_FL_FREE); | |
3133 | ftrace_free_rec(rec); | |
3134 | } | |
3135 | } while_for_each_ftrace_rec(); | |
45a4a237 | 3136 | out_unlock: |
93eb677d SR |
3137 | mutex_unlock(&ftrace_lock); |
3138 | } | |
3139 | ||
3140 | static void ftrace_init_module(struct module *mod, | |
3141 | unsigned long *start, unsigned long *end) | |
90d595fe | 3142 | { |
00fd61ae | 3143 | if (ftrace_disabled || start == end) |
fed1939c | 3144 | return; |
5cb084bb | 3145 | ftrace_process_locs(mod, start, end); |
90d595fe SR |
3146 | } |
3147 | ||
93eb677d SR |
3148 | static int ftrace_module_notify(struct notifier_block *self, |
3149 | unsigned long val, void *data) | |
3150 | { | |
3151 | struct module *mod = data; | |
3152 | ||
3153 | switch (val) { | |
3154 | case MODULE_STATE_COMING: | |
3155 | ftrace_init_module(mod, mod->ftrace_callsites, | |
3156 | mod->ftrace_callsites + | |
3157 | mod->num_ftrace_callsites); | |
3158 | break; | |
3159 | case MODULE_STATE_GOING: | |
e7247a15 | 3160 | ftrace_release_mod(mod); |
93eb677d SR |
3161 | break; |
3162 | } | |
3163 | ||
3164 | return 0; | |
3165 | } | |
3166 | #else | |
3167 | static int ftrace_module_notify(struct notifier_block *self, | |
3168 | unsigned long val, void *data) | |
3169 | { | |
3170 | return 0; | |
3171 | } | |
3172 | #endif /* CONFIG_MODULES */ | |
3173 | ||
3174 | struct notifier_block ftrace_module_nb = { | |
3175 | .notifier_call = ftrace_module_notify, | |
3176 | .priority = 0, | |
3177 | }; | |
3178 | ||
68bf21aa SR |
3179 | extern unsigned long __start_mcount_loc[]; |
3180 | extern unsigned long __stop_mcount_loc[]; | |
3181 | ||
3182 | void __init ftrace_init(void) | |
3183 | { | |
3184 | unsigned long count, addr, flags; | |
3185 | int ret; | |
3186 | ||
3187 | /* Keep the ftrace pointer to the stub */ | |
3188 | addr = (unsigned long)ftrace_stub; | |
3189 | ||
3190 | local_irq_save(flags); | |
3191 | ftrace_dyn_arch_init(&addr); | |
3192 | local_irq_restore(flags); | |
3193 | ||
3194 | /* ftrace_dyn_arch_init places the return code in addr */ | |
3195 | if (addr) | |
3196 | goto failed; | |
3197 | ||
3198 | count = __stop_mcount_loc - __start_mcount_loc; | |
3199 | ||
3200 | ret = ftrace_dyn_table_alloc(count); | |
3201 | if (ret) | |
3202 | goto failed; | |
3203 | ||
3204 | last_ftrace_enabled = ftrace_enabled = 1; | |
3205 | ||
5cb084bb | 3206 | ret = ftrace_process_locs(NULL, |
31e88909 | 3207 | __start_mcount_loc, |
68bf21aa SR |
3208 | __stop_mcount_loc); |
3209 | ||
93eb677d | 3210 | ret = register_module_notifier(&ftrace_module_nb); |
24ed0c4b | 3211 | if (ret) |
93eb677d SR |
3212 | pr_warning("Failed to register trace ftrace module notifier\n"); |
3213 | ||
2af15d6a SR |
3214 | set_ftrace_early_filters(); |
3215 | ||
68bf21aa SR |
3216 | return; |
3217 | failed: | |
3218 | ftrace_disabled = 1; | |
3219 | } | |
68bf21aa | 3220 | |
3d083395 | 3221 | #else |
0b6e4d56 FW |
3222 | |
3223 | static int __init ftrace_nodyn_init(void) | |
3224 | { | |
3225 | ftrace_enabled = 1; | |
3226 | return 0; | |
3227 | } | |
3228 | device_initcall(ftrace_nodyn_init); | |
3229 | ||
df4fc315 SR |
3230 | static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } |
3231 | static inline void ftrace_startup_enable(int command) { } | |
5a45cfe1 SR |
3232 | /* Keep as macros so we do not need to define the commands */ |
3233 | # define ftrace_startup(command) do { } while (0) | |
3234 | # define ftrace_shutdown(command) do { } while (0) | |
c7aafc54 IM |
3235 | # define ftrace_startup_sysctl() do { } while (0) |
3236 | # define ftrace_shutdown_sysctl() do { } while (0) | |
3d083395 SR |
3237 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
3238 | ||
e32d8956 | 3239 | static void clear_ftrace_swapper(void) |
978f3a45 SR |
3240 | { |
3241 | struct task_struct *p; | |
e32d8956 | 3242 | int cpu; |
978f3a45 | 3243 | |
e32d8956 SR |
3244 | get_online_cpus(); |
3245 | for_each_online_cpu(cpu) { | |
3246 | p = idle_task(cpu); | |
978f3a45 | 3247 | clear_tsk_trace_trace(p); |
e32d8956 SR |
3248 | } |
3249 | put_online_cpus(); | |
3250 | } | |
978f3a45 | 3251 | |
e32d8956 SR |
3252 | static void set_ftrace_swapper(void) |
3253 | { | |
3254 | struct task_struct *p; | |
3255 | int cpu; | |
3256 | ||
3257 | get_online_cpus(); | |
3258 | for_each_online_cpu(cpu) { | |
3259 | p = idle_task(cpu); | |
3260 | set_tsk_trace_trace(p); | |
3261 | } | |
3262 | put_online_cpus(); | |
978f3a45 SR |
3263 | } |
3264 | ||
e32d8956 SR |
3265 | static void clear_ftrace_pid(struct pid *pid) |
3266 | { | |
3267 | struct task_struct *p; | |
3268 | ||
229c4ef8 | 3269 | rcu_read_lock(); |
e32d8956 SR |
3270 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
3271 | clear_tsk_trace_trace(p); | |
3272 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 ON |
3273 | rcu_read_unlock(); |
3274 | ||
e32d8956 SR |
3275 | put_pid(pid); |
3276 | } | |
3277 | ||
3278 | static void set_ftrace_pid(struct pid *pid) | |
978f3a45 SR |
3279 | { |
3280 | struct task_struct *p; | |
3281 | ||
229c4ef8 | 3282 | rcu_read_lock(); |
978f3a45 SR |
3283 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
3284 | set_tsk_trace_trace(p); | |
3285 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 | 3286 | rcu_read_unlock(); |
978f3a45 SR |
3287 | } |
3288 | ||
756d17ee | 3289 | static void clear_ftrace_pid_task(struct pid *pid) |
e32d8956 | 3290 | { |
756d17ee | 3291 | if (pid == ftrace_swapper_pid) |
e32d8956 SR |
3292 | clear_ftrace_swapper(); |
3293 | else | |
756d17ee | 3294 | clear_ftrace_pid(pid); |
e32d8956 SR |
3295 | } |
3296 | ||
3297 | static void set_ftrace_pid_task(struct pid *pid) | |
3298 | { | |
3299 | if (pid == ftrace_swapper_pid) | |
3300 | set_ftrace_swapper(); | |
3301 | else | |
3302 | set_ftrace_pid(pid); | |
3303 | } | |
3304 | ||
756d17ee | 3305 | static int ftrace_pid_add(int p) |
df4fc315 | 3306 | { |
978f3a45 | 3307 | struct pid *pid; |
756d17ee | 3308 | struct ftrace_pid *fpid; |
3309 | int ret = -EINVAL; | |
df4fc315 | 3310 | |
756d17ee | 3311 | mutex_lock(&ftrace_lock); |
df4fc315 | 3312 | |
756d17ee | 3313 | if (!p) |
3314 | pid = ftrace_swapper_pid; | |
3315 | else | |
3316 | pid = find_get_pid(p); | |
df4fc315 | 3317 | |
756d17ee | 3318 | if (!pid) |
3319 | goto out; | |
df4fc315 | 3320 | |
756d17ee | 3321 | ret = 0; |
df4fc315 | 3322 | |
756d17ee | 3323 | list_for_each_entry(fpid, &ftrace_pids, list) |
3324 | if (fpid->pid == pid) | |
3325 | goto out_put; | |
978f3a45 | 3326 | |
756d17ee | 3327 | ret = -ENOMEM; |
df4fc315 | 3328 | |
756d17ee | 3329 | fpid = kmalloc(sizeof(*fpid), GFP_KERNEL); |
3330 | if (!fpid) | |
3331 | goto out_put; | |
df4fc315 | 3332 | |
756d17ee | 3333 | list_add(&fpid->list, &ftrace_pids); |
3334 | fpid->pid = pid; | |
0ef8cde5 | 3335 | |
756d17ee | 3336 | set_ftrace_pid_task(pid); |
978f3a45 | 3337 | |
756d17ee | 3338 | ftrace_update_pid_func(); |
3339 | ftrace_startup_enable(0); | |
3340 | ||
3341 | mutex_unlock(&ftrace_lock); | |
3342 | return 0; | |
3343 | ||
3344 | out_put: | |
3345 | if (pid != ftrace_swapper_pid) | |
3346 | put_pid(pid); | |
978f3a45 | 3347 | |
756d17ee | 3348 | out: |
3349 | mutex_unlock(&ftrace_lock); | |
3350 | return ret; | |
3351 | } | |
3352 | ||
3353 | static void ftrace_pid_reset(void) | |
3354 | { | |
3355 | struct ftrace_pid *fpid, *safe; | |
978f3a45 | 3356 | |
756d17ee | 3357 | mutex_lock(&ftrace_lock); |
3358 | list_for_each_entry_safe(fpid, safe, &ftrace_pids, list) { | |
3359 | struct pid *pid = fpid->pid; | |
3360 | ||
3361 | clear_ftrace_pid_task(pid); | |
3362 | ||
3363 | list_del(&fpid->list); | |
3364 | kfree(fpid); | |
df4fc315 SR |
3365 | } |
3366 | ||
df4fc315 SR |
3367 | ftrace_update_pid_func(); |
3368 | ftrace_startup_enable(0); | |
3369 | ||
e6ea44e9 | 3370 | mutex_unlock(&ftrace_lock); |
756d17ee | 3371 | } |
df4fc315 | 3372 | |
756d17ee | 3373 | static void *fpid_start(struct seq_file *m, loff_t *pos) |
3374 | { | |
3375 | mutex_lock(&ftrace_lock); | |
3376 | ||
3377 | if (list_empty(&ftrace_pids) && (!*pos)) | |
3378 | return (void *) 1; | |
3379 | ||
3380 | return seq_list_start(&ftrace_pids, *pos); | |
3381 | } | |
3382 | ||
3383 | static void *fpid_next(struct seq_file *m, void *v, loff_t *pos) | |
3384 | { | |
3385 | if (v == (void *)1) | |
3386 | return NULL; | |
3387 | ||
3388 | return seq_list_next(v, &ftrace_pids, pos); | |
3389 | } | |
3390 | ||
3391 | static void fpid_stop(struct seq_file *m, void *p) | |
3392 | { | |
3393 | mutex_unlock(&ftrace_lock); | |
3394 | } | |
3395 | ||
3396 | static int fpid_show(struct seq_file *m, void *v) | |
3397 | { | |
3398 | const struct ftrace_pid *fpid = list_entry(v, struct ftrace_pid, list); | |
3399 | ||
3400 | if (v == (void *)1) { | |
3401 | seq_printf(m, "no pid\n"); | |
3402 | return 0; | |
3403 | } | |
3404 | ||
3405 | if (fpid->pid == ftrace_swapper_pid) | |
3406 | seq_printf(m, "swapper tasks\n"); | |
3407 | else | |
3408 | seq_printf(m, "%u\n", pid_vnr(fpid->pid)); | |
3409 | ||
3410 | return 0; | |
3411 | } | |
3412 | ||
3413 | static const struct seq_operations ftrace_pid_sops = { | |
3414 | .start = fpid_start, | |
3415 | .next = fpid_next, | |
3416 | .stop = fpid_stop, | |
3417 | .show = fpid_show, | |
3418 | }; | |
3419 | ||
3420 | static int | |
3421 | ftrace_pid_open(struct inode *inode, struct file *file) | |
3422 | { | |
3423 | int ret = 0; | |
3424 | ||
3425 | if ((file->f_mode & FMODE_WRITE) && | |
3426 | (file->f_flags & O_TRUNC)) | |
3427 | ftrace_pid_reset(); | |
3428 | ||
3429 | if (file->f_mode & FMODE_READ) | |
3430 | ret = seq_open(file, &ftrace_pid_sops); | |
3431 | ||
3432 | return ret; | |
3433 | } | |
3434 | ||
df4fc315 SR |
3435 | static ssize_t |
3436 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
3437 | size_t cnt, loff_t *ppos) | |
3438 | { | |
457dc928 | 3439 | char buf[64], *tmp; |
df4fc315 SR |
3440 | long val; |
3441 | int ret; | |
3442 | ||
3443 | if (cnt >= sizeof(buf)) | |
3444 | return -EINVAL; | |
3445 | ||
3446 | if (copy_from_user(&buf, ubuf, cnt)) | |
3447 | return -EFAULT; | |
3448 | ||
3449 | buf[cnt] = 0; | |
3450 | ||
756d17ee | 3451 | /* |
3452 | * Allow "echo > set_ftrace_pid" or "echo -n '' > set_ftrace_pid" | |
3453 | * to clean the filter quietly. | |
3454 | */ | |
457dc928 IM |
3455 | tmp = strstrip(buf); |
3456 | if (strlen(tmp) == 0) | |
756d17ee | 3457 | return 1; |
3458 | ||
457dc928 | 3459 | ret = strict_strtol(tmp, 10, &val); |
df4fc315 SR |
3460 | if (ret < 0) |
3461 | return ret; | |
3462 | ||
756d17ee | 3463 | ret = ftrace_pid_add(val); |
df4fc315 | 3464 | |
756d17ee | 3465 | return ret ? ret : cnt; |
3466 | } | |
df4fc315 | 3467 | |
756d17ee | 3468 | static int |
3469 | ftrace_pid_release(struct inode *inode, struct file *file) | |
3470 | { | |
3471 | if (file->f_mode & FMODE_READ) | |
3472 | seq_release(inode, file); | |
df4fc315 | 3473 | |
756d17ee | 3474 | return 0; |
df4fc315 SR |
3475 | } |
3476 | ||
5e2336a0 | 3477 | static const struct file_operations ftrace_pid_fops = { |
756d17ee | 3478 | .open = ftrace_pid_open, |
3479 | .write = ftrace_pid_write, | |
3480 | .read = seq_read, | |
3481 | .llseek = seq_lseek, | |
3482 | .release = ftrace_pid_release, | |
df4fc315 SR |
3483 | }; |
3484 | ||
3485 | static __init int ftrace_init_debugfs(void) | |
3486 | { | |
3487 | struct dentry *d_tracer; | |
df4fc315 SR |
3488 | |
3489 | d_tracer = tracing_init_dentry(); | |
3490 | if (!d_tracer) | |
3491 | return 0; | |
3492 | ||
3493 | ftrace_init_dyn_debugfs(d_tracer); | |
3494 | ||
5452af66 FW |
3495 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
3496 | NULL, &ftrace_pid_fops); | |
493762fc SR |
3497 | |
3498 | ftrace_profile_debugfs(d_tracer); | |
3499 | ||
df4fc315 SR |
3500 | return 0; |
3501 | } | |
df4fc315 SR |
3502 | fs_initcall(ftrace_init_debugfs); |
3503 | ||
a2bb6a3d | 3504 | /** |
81adbdc0 | 3505 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
3506 | * |
3507 | * This function should be used by panic code. It stops ftrace | |
3508 | * but in a not so nice way. If you need to simply kill ftrace | |
3509 | * from a non-atomic section, use ftrace_kill. | |
3510 | */ | |
81adbdc0 | 3511 | void ftrace_kill(void) |
a2bb6a3d SR |
3512 | { |
3513 | ftrace_disabled = 1; | |
3514 | ftrace_enabled = 0; | |
a2bb6a3d SR |
3515 | clear_ftrace_function(); |
3516 | } | |
3517 | ||
16444a8a | 3518 | /** |
3d083395 SR |
3519 | * register_ftrace_function - register a function for profiling |
3520 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 3521 | * |
3d083395 SR |
3522 | * Register a function to be called by all functions in the |
3523 | * kernel. | |
3524 | * | |
3525 | * Note: @ops->func and all the functions it calls must be labeled | |
3526 | * with "notrace", otherwise it will go into a | |
3527 | * recursive loop. | |
16444a8a | 3528 | */ |
3d083395 | 3529 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 3530 | { |
45a4a237 | 3531 | int ret = -1; |
4eebcc81 | 3532 | |
e6ea44e9 | 3533 | mutex_lock(&ftrace_lock); |
e7d3737e | 3534 | |
45a4a237 SR |
3535 | if (unlikely(ftrace_disabled)) |
3536 | goto out_unlock; | |
3537 | ||
b0fc494f | 3538 | ret = __register_ftrace_function(ops); |
5a45cfe1 | 3539 | ftrace_startup(0); |
b0fc494f | 3540 | |
45a4a237 | 3541 | out_unlock: |
e6ea44e9 | 3542 | mutex_unlock(&ftrace_lock); |
b0fc494f | 3543 | return ret; |
3d083395 SR |
3544 | } |
3545 | ||
3546 | /** | |
32632920 | 3547 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
3548 | * @ops - ops structure that holds the function to unregister |
3549 | * | |
3550 | * Unregister a function that was added to be called by ftrace profiling. | |
3551 | */ | |
3552 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
3553 | { | |
3554 | int ret; | |
3555 | ||
e6ea44e9 | 3556 | mutex_lock(&ftrace_lock); |
3d083395 | 3557 | ret = __unregister_ftrace_function(ops); |
5a45cfe1 | 3558 | ftrace_shutdown(0); |
e6ea44e9 | 3559 | mutex_unlock(&ftrace_lock); |
b0fc494f SR |
3560 | |
3561 | return ret; | |
3562 | } | |
3563 | ||
e309b41d | 3564 | int |
b0fc494f | 3565 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
8d65af78 | 3566 | void __user *buffer, size_t *lenp, |
b0fc494f SR |
3567 | loff_t *ppos) |
3568 | { | |
45a4a237 | 3569 | int ret = -ENODEV; |
4eebcc81 | 3570 | |
e6ea44e9 | 3571 | mutex_lock(&ftrace_lock); |
b0fc494f | 3572 | |
45a4a237 SR |
3573 | if (unlikely(ftrace_disabled)) |
3574 | goto out; | |
3575 | ||
3576 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
b0fc494f | 3577 | |
a32c7765 | 3578 | if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) |
b0fc494f SR |
3579 | goto out; |
3580 | ||
a32c7765 | 3581 | last_ftrace_enabled = !!ftrace_enabled; |
b0fc494f SR |
3582 | |
3583 | if (ftrace_enabled) { | |
3584 | ||
3585 | ftrace_startup_sysctl(); | |
3586 | ||
3587 | /* we are starting ftrace again */ | |
3588 | if (ftrace_list != &ftrace_list_end) { | |
3589 | if (ftrace_list->next == &ftrace_list_end) | |
3590 | ftrace_trace_function = ftrace_list->func; | |
3591 | else | |
3592 | ftrace_trace_function = ftrace_list_func; | |
3593 | } | |
3594 | ||
3595 | } else { | |
3596 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
3597 | ftrace_trace_function = ftrace_stub; | |
3598 | ||
3599 | ftrace_shutdown_sysctl(); | |
3600 | } | |
3601 | ||
3602 | out: | |
e6ea44e9 | 3603 | mutex_unlock(&ftrace_lock); |
3d083395 | 3604 | return ret; |
16444a8a | 3605 | } |
f17845e5 | 3606 | |
fb52607a | 3607 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 3608 | |
597af815 | 3609 | static int ftrace_graph_active; |
4a2b8dda | 3610 | static struct notifier_block ftrace_suspend_notifier; |
e7d3737e | 3611 | |
e49dc19c SR |
3612 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
3613 | { | |
3614 | return 0; | |
3615 | } | |
3616 | ||
287b6e68 FW |
3617 | /* The callbacks that hook a function */ |
3618 | trace_func_graph_ret_t ftrace_graph_return = | |
3619 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 3620 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
3621 | |
3622 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
3623 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
3624 | { | |
3625 | int i; | |
3626 | int ret = 0; | |
3627 | unsigned long flags; | |
3628 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; | |
3629 | struct task_struct *g, *t; | |
3630 | ||
3631 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
3632 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
3633 | * sizeof(struct ftrace_ret_stack), | |
3634 | GFP_KERNEL); | |
3635 | if (!ret_stack_list[i]) { | |
3636 | start = 0; | |
3637 | end = i; | |
3638 | ret = -ENOMEM; | |
3639 | goto free; | |
3640 | } | |
3641 | } | |
3642 | ||
3643 | read_lock_irqsave(&tasklist_lock, flags); | |
3644 | do_each_thread(g, t) { | |
3645 | if (start == end) { | |
3646 | ret = -EAGAIN; | |
3647 | goto unlock; | |
3648 | } | |
3649 | ||
3650 | if (t->ret_stack == NULL) { | |
380c4b14 | 3651 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 | 3652 | atomic_set(&t->trace_overrun, 0); |
26c01624 SR |
3653 | t->curr_ret_stack = -1; |
3654 | /* Make sure the tasks see the -1 first: */ | |
3655 | smp_wmb(); | |
3656 | t->ret_stack = ret_stack_list[start++]; | |
f201ae23 FW |
3657 | } |
3658 | } while_each_thread(g, t); | |
3659 | ||
3660 | unlock: | |
3661 | read_unlock_irqrestore(&tasklist_lock, flags); | |
3662 | free: | |
3663 | for (i = start; i < end; i++) | |
3664 | kfree(ret_stack_list[i]); | |
3665 | return ret; | |
3666 | } | |
3667 | ||
8aef2d28 | 3668 | static void |
38516ab5 SR |
3669 | ftrace_graph_probe_sched_switch(void *ignore, |
3670 | struct task_struct *prev, struct task_struct *next) | |
8aef2d28 SR |
3671 | { |
3672 | unsigned long long timestamp; | |
3673 | int index; | |
3674 | ||
be6f164a SR |
3675 | /* |
3676 | * Does the user want to count the time a function was asleep. | |
3677 | * If so, do not update the time stamps. | |
3678 | */ | |
3679 | if (trace_flags & TRACE_ITER_SLEEP_TIME) | |
3680 | return; | |
3681 | ||
8aef2d28 SR |
3682 | timestamp = trace_clock_local(); |
3683 | ||
3684 | prev->ftrace_timestamp = timestamp; | |
3685 | ||
3686 | /* only process tasks that we timestamped */ | |
3687 | if (!next->ftrace_timestamp) | |
3688 | return; | |
3689 | ||
3690 | /* | |
3691 | * Update all the counters in next to make up for the | |
3692 | * time next was sleeping. | |
3693 | */ | |
3694 | timestamp -= next->ftrace_timestamp; | |
3695 | ||
3696 | for (index = next->curr_ret_stack; index >= 0; index--) | |
3697 | next->ret_stack[index].calltime += timestamp; | |
3698 | } | |
3699 | ||
f201ae23 | 3700 | /* Allocate a return stack for each task */ |
fb52607a | 3701 | static int start_graph_tracing(void) |
f201ae23 FW |
3702 | { |
3703 | struct ftrace_ret_stack **ret_stack_list; | |
5b058bcd | 3704 | int ret, cpu; |
f201ae23 FW |
3705 | |
3706 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
3707 | sizeof(struct ftrace_ret_stack *), | |
3708 | GFP_KERNEL); | |
3709 | ||
3710 | if (!ret_stack_list) | |
3711 | return -ENOMEM; | |
3712 | ||
5b058bcd | 3713 | /* The cpu_boot init_task->ret_stack will never be freed */ |
179c498a SR |
3714 | for_each_online_cpu(cpu) { |
3715 | if (!idle_task(cpu)->ret_stack) | |
868baf07 | 3716 | ftrace_graph_init_idle_task(idle_task(cpu), cpu); |
179c498a | 3717 | } |
5b058bcd | 3718 | |
f201ae23 FW |
3719 | do { |
3720 | ret = alloc_retstack_tasklist(ret_stack_list); | |
3721 | } while (ret == -EAGAIN); | |
3722 | ||
8aef2d28 | 3723 | if (!ret) { |
38516ab5 | 3724 | ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
8aef2d28 SR |
3725 | if (ret) |
3726 | pr_info("ftrace_graph: Couldn't activate tracepoint" | |
3727 | " probe to kernel_sched_switch\n"); | |
3728 | } | |
3729 | ||
f201ae23 FW |
3730 | kfree(ret_stack_list); |
3731 | return ret; | |
3732 | } | |
3733 | ||
4a2b8dda FW |
3734 | /* |
3735 | * Hibernation protection. | |
3736 | * The state of the current task is too much unstable during | |
3737 | * suspend/restore to disk. We want to protect against that. | |
3738 | */ | |
3739 | static int | |
3740 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, | |
3741 | void *unused) | |
3742 | { | |
3743 | switch (state) { | |
3744 | case PM_HIBERNATION_PREPARE: | |
3745 | pause_graph_tracing(); | |
3746 | break; | |
3747 | ||
3748 | case PM_POST_HIBERNATION: | |
3749 | unpause_graph_tracing(); | |
3750 | break; | |
3751 | } | |
3752 | return NOTIFY_DONE; | |
3753 | } | |
3754 | ||
287b6e68 FW |
3755 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
3756 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 3757 | { |
e7d3737e FW |
3758 | int ret = 0; |
3759 | ||
e6ea44e9 | 3760 | mutex_lock(&ftrace_lock); |
e7d3737e | 3761 | |
05ce5818 | 3762 | /* we currently allow only one tracer registered at a time */ |
597af815 | 3763 | if (ftrace_graph_active) { |
05ce5818 SR |
3764 | ret = -EBUSY; |
3765 | goto out; | |
3766 | } | |
3767 | ||
4a2b8dda FW |
3768 | ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call; |
3769 | register_pm_notifier(&ftrace_suspend_notifier); | |
3770 | ||
597af815 | 3771 | ftrace_graph_active++; |
fb52607a | 3772 | ret = start_graph_tracing(); |
f201ae23 | 3773 | if (ret) { |
597af815 | 3774 | ftrace_graph_active--; |
f201ae23 FW |
3775 | goto out; |
3776 | } | |
e53a6319 | 3777 | |
287b6e68 FW |
3778 | ftrace_graph_return = retfunc; |
3779 | ftrace_graph_entry = entryfunc; | |
e53a6319 | 3780 | |
5a45cfe1 | 3781 | ftrace_startup(FTRACE_START_FUNC_RET); |
e7d3737e FW |
3782 | |
3783 | out: | |
e6ea44e9 | 3784 | mutex_unlock(&ftrace_lock); |
e7d3737e | 3785 | return ret; |
15e6cb36 FW |
3786 | } |
3787 | ||
fb52607a | 3788 | void unregister_ftrace_graph(void) |
15e6cb36 | 3789 | { |
e6ea44e9 | 3790 | mutex_lock(&ftrace_lock); |
e7d3737e | 3791 | |
597af815 | 3792 | if (unlikely(!ftrace_graph_active)) |
2aad1b76 SR |
3793 | goto out; |
3794 | ||
597af815 | 3795 | ftrace_graph_active--; |
287b6e68 | 3796 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; |
e49dc19c | 3797 | ftrace_graph_entry = ftrace_graph_entry_stub; |
5a45cfe1 | 3798 | ftrace_shutdown(FTRACE_STOP_FUNC_RET); |
4a2b8dda | 3799 | unregister_pm_notifier(&ftrace_suspend_notifier); |
38516ab5 | 3800 | unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
e7d3737e | 3801 | |
2aad1b76 | 3802 | out: |
e6ea44e9 | 3803 | mutex_unlock(&ftrace_lock); |
15e6cb36 | 3804 | } |
f201ae23 | 3805 | |
868baf07 SR |
3806 | static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack); |
3807 | ||
3808 | static void | |
3809 | graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack) | |
3810 | { | |
3811 | atomic_set(&t->tracing_graph_pause, 0); | |
3812 | atomic_set(&t->trace_overrun, 0); | |
3813 | t->ftrace_timestamp = 0; | |
25985edc | 3814 | /* make curr_ret_stack visible before we add the ret_stack */ |
868baf07 SR |
3815 | smp_wmb(); |
3816 | t->ret_stack = ret_stack; | |
3817 | } | |
3818 | ||
3819 | /* | |
3820 | * Allocate a return stack for the idle task. May be the first | |
3821 | * time through, or it may be done by CPU hotplug online. | |
3822 | */ | |
3823 | void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) | |
3824 | { | |
3825 | t->curr_ret_stack = -1; | |
3826 | /* | |
3827 | * The idle task has no parent, it either has its own | |
3828 | * stack or no stack at all. | |
3829 | */ | |
3830 | if (t->ret_stack) | |
3831 | WARN_ON(t->ret_stack != per_cpu(idle_ret_stack, cpu)); | |
3832 | ||
3833 | if (ftrace_graph_active) { | |
3834 | struct ftrace_ret_stack *ret_stack; | |
3835 | ||
3836 | ret_stack = per_cpu(idle_ret_stack, cpu); | |
3837 | if (!ret_stack) { | |
3838 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
3839 | * sizeof(struct ftrace_ret_stack), | |
3840 | GFP_KERNEL); | |
3841 | if (!ret_stack) | |
3842 | return; | |
3843 | per_cpu(idle_ret_stack, cpu) = ret_stack; | |
3844 | } | |
3845 | graph_init_task(t, ret_stack); | |
3846 | } | |
3847 | } | |
3848 | ||
f201ae23 | 3849 | /* Allocate a return stack for newly created task */ |
fb52607a | 3850 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 3851 | { |
84047e36 SR |
3852 | /* Make sure we do not use the parent ret_stack */ |
3853 | t->ret_stack = NULL; | |
ea14eb71 | 3854 | t->curr_ret_stack = -1; |
84047e36 | 3855 | |
597af815 | 3856 | if (ftrace_graph_active) { |
82310a32 SR |
3857 | struct ftrace_ret_stack *ret_stack; |
3858 | ||
3859 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
f201ae23 FW |
3860 | * sizeof(struct ftrace_ret_stack), |
3861 | GFP_KERNEL); | |
82310a32 | 3862 | if (!ret_stack) |
f201ae23 | 3863 | return; |
868baf07 | 3864 | graph_init_task(t, ret_stack); |
84047e36 | 3865 | } |
f201ae23 FW |
3866 | } |
3867 | ||
fb52607a | 3868 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 3869 | { |
eae849ca FW |
3870 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
3871 | ||
f201ae23 | 3872 | t->ret_stack = NULL; |
eae849ca FW |
3873 | /* NULL must become visible to IRQs before we free it: */ |
3874 | barrier(); | |
3875 | ||
3876 | kfree(ret_stack); | |
f201ae23 | 3877 | } |
14a866c5 SR |
3878 | |
3879 | void ftrace_graph_stop(void) | |
3880 | { | |
3881 | ftrace_stop(); | |
3882 | } | |
15e6cb36 | 3883 | #endif |