Commit | Line | Data |
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16444a8a ACM |
1 | /* |
2 | * Infrastructure for profiling code inserted by 'gcc -pg'. | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2004-2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally ported from the -rt patch by: | |
8 | * Copyright (C) 2007 Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code in the latency_tracer, that is: | |
11 | * | |
12 | * Copyright (C) 2004-2006 Ingo Molnar | |
13 | * Copyright (C) 2004 William Lee Irwin III | |
14 | */ | |
15 | ||
3d083395 SR |
16 | #include <linux/stop_machine.h> |
17 | #include <linux/clocksource.h> | |
18 | #include <linux/kallsyms.h> | |
5072c59f | 19 | #include <linux/seq_file.h> |
4a2b8dda | 20 | #include <linux/suspend.h> |
5072c59f | 21 | #include <linux/debugfs.h> |
3d083395 | 22 | #include <linux/hardirq.h> |
2d8b820b | 23 | #include <linux/kthread.h> |
5072c59f | 24 | #include <linux/uaccess.h> |
5855fead | 25 | #include <linux/bsearch.h> |
56d82e00 | 26 | #include <linux/module.h> |
2d8b820b | 27 | #include <linux/ftrace.h> |
b0fc494f | 28 | #include <linux/sysctl.h> |
5a0e3ad6 | 29 | #include <linux/slab.h> |
5072c59f | 30 | #include <linux/ctype.h> |
68950619 | 31 | #include <linux/sort.h> |
3d083395 | 32 | #include <linux/list.h> |
59df055f | 33 | #include <linux/hash.h> |
3f379b03 | 34 | #include <linux/rcupdate.h> |
3d083395 | 35 | |
ad8d75ff | 36 | #include <trace/events/sched.h> |
8aef2d28 | 37 | |
2af15d6a | 38 | #include <asm/setup.h> |
395a59d0 | 39 | |
0706f1c4 | 40 | #include "trace_output.h" |
bac429f0 | 41 | #include "trace_stat.h" |
16444a8a | 42 | |
6912896e | 43 | #define FTRACE_WARN_ON(cond) \ |
0778d9ad SR |
44 | ({ \ |
45 | int ___r = cond; \ | |
46 | if (WARN_ON(___r)) \ | |
6912896e | 47 | ftrace_kill(); \ |
0778d9ad SR |
48 | ___r; \ |
49 | }) | |
6912896e SR |
50 | |
51 | #define FTRACE_WARN_ON_ONCE(cond) \ | |
0778d9ad SR |
52 | ({ \ |
53 | int ___r = cond; \ | |
54 | if (WARN_ON_ONCE(___r)) \ | |
6912896e | 55 | ftrace_kill(); \ |
0778d9ad SR |
56 | ___r; \ |
57 | }) | |
6912896e | 58 | |
8fc0c701 SR |
59 | /* hash bits for specific function selection */ |
60 | #define FTRACE_HASH_BITS 7 | |
61 | #define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS) | |
33dc9b12 SR |
62 | #define FTRACE_HASH_DEFAULT_BITS 10 |
63 | #define FTRACE_HASH_MAX_BITS 12 | |
8fc0c701 | 64 | |
e248491a JO |
65 | #define FL_GLOBAL_CONTROL_MASK (FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_CONTROL) |
66 | ||
2f5f6ad9 SR |
67 | static struct ftrace_ops ftrace_list_end __read_mostly = { |
68 | .func = ftrace_stub, | |
4740974a | 69 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
2f5f6ad9 SR |
70 | }; |
71 | ||
4eebcc81 SR |
72 | /* ftrace_enabled is a method to turn ftrace on or off */ |
73 | int ftrace_enabled __read_mostly; | |
d61f82d0 | 74 | static int last_ftrace_enabled; |
b0fc494f | 75 | |
60a7ecf4 | 76 | /* Quick disabling of function tracer. */ |
2f5f6ad9 SR |
77 | int function_trace_stop __read_mostly; |
78 | ||
79 | /* Current function tracing op */ | |
80 | struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end; | |
60a7ecf4 | 81 | |
756d17ee | 82 | /* List for set_ftrace_pid's pids. */ |
83 | LIST_HEAD(ftrace_pids); | |
84 | struct ftrace_pid { | |
85 | struct list_head list; | |
86 | struct pid *pid; | |
87 | }; | |
88 | ||
4eebcc81 SR |
89 | /* |
90 | * ftrace_disabled is set when an anomaly is discovered. | |
91 | * ftrace_disabled is much stronger than ftrace_enabled. | |
92 | */ | |
93 | static int ftrace_disabled __read_mostly; | |
94 | ||
52baf119 | 95 | static DEFINE_MUTEX(ftrace_lock); |
b0fc494f | 96 | |
b848914c | 97 | static struct ftrace_ops *ftrace_global_list __read_mostly = &ftrace_list_end; |
e248491a | 98 | static struct ftrace_ops *ftrace_control_list __read_mostly = &ftrace_list_end; |
b848914c | 99 | static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end; |
16444a8a | 100 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; |
df4fc315 | 101 | ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub; |
2b499381 | 102 | static struct ftrace_ops global_ops; |
e248491a | 103 | static struct ftrace_ops control_ops; |
16444a8a | 104 | |
2f5f6ad9 SR |
105 | #if ARCH_SUPPORTS_FTRACE_OPS |
106 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 107 | struct ftrace_ops *op, struct pt_regs *regs); |
2f5f6ad9 SR |
108 | #else |
109 | /* See comment below, where ftrace_ops_list_func is defined */ | |
110 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip); | |
111 | #define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops) | |
112 | #endif | |
b848914c | 113 | |
ea701f11 SR |
114 | /** |
115 | * ftrace_nr_registered_ops - return number of ops registered | |
116 | * | |
117 | * Returns the number of ftrace_ops registered and tracing functions | |
118 | */ | |
119 | int ftrace_nr_registered_ops(void) | |
120 | { | |
121 | struct ftrace_ops *ops; | |
122 | int cnt = 0; | |
123 | ||
124 | mutex_lock(&ftrace_lock); | |
125 | ||
126 | for (ops = ftrace_ops_list; | |
127 | ops != &ftrace_list_end; ops = ops->next) | |
128 | cnt++; | |
129 | ||
130 | mutex_unlock(&ftrace_lock); | |
131 | ||
132 | return cnt; | |
133 | } | |
134 | ||
3f379b03 | 135 | /* |
b848914c | 136 | * Traverse the ftrace_global_list, invoking all entries. The reason that we |
3f379b03 PM |
137 | * can use rcu_dereference_raw() is that elements removed from this list |
138 | * are simply leaked, so there is no need to interact with a grace-period | |
139 | * mechanism. The rcu_dereference_raw() calls are needed to handle | |
b848914c | 140 | * concurrent insertions into the ftrace_global_list. |
3f379b03 PM |
141 | * |
142 | * Silly Alpha and silly pointer-speculation compiler optimizations! | |
143 | */ | |
2f5f6ad9 SR |
144 | static void |
145 | ftrace_global_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 146 | struct ftrace_ops *op, struct pt_regs *regs) |
16444a8a | 147 | { |
b1cff0ad SR |
148 | if (unlikely(trace_recursion_test(TRACE_GLOBAL_BIT))) |
149 | return; | |
16444a8a | 150 | |
b1cff0ad SR |
151 | trace_recursion_set(TRACE_GLOBAL_BIT); |
152 | op = rcu_dereference_raw(ftrace_global_list); /*see above*/ | |
16444a8a | 153 | while (op != &ftrace_list_end) { |
a1e2e31d | 154 | op->func(ip, parent_ip, op, regs); |
3f379b03 | 155 | op = rcu_dereference_raw(op->next); /*see above*/ |
16444a8a | 156 | }; |
b1cff0ad | 157 | trace_recursion_clear(TRACE_GLOBAL_BIT); |
16444a8a ACM |
158 | } |
159 | ||
2f5f6ad9 | 160 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 161 | struct ftrace_ops *op, struct pt_regs *regs) |
df4fc315 | 162 | { |
0ef8cde5 | 163 | if (!test_tsk_trace_trace(current)) |
df4fc315 SR |
164 | return; |
165 | ||
a1e2e31d | 166 | ftrace_pid_function(ip, parent_ip, op, regs); |
df4fc315 SR |
167 | } |
168 | ||
169 | static void set_ftrace_pid_function(ftrace_func_t func) | |
170 | { | |
171 | /* do not set ftrace_pid_function to itself! */ | |
172 | if (func != ftrace_pid_func) | |
173 | ftrace_pid_function = func; | |
174 | } | |
175 | ||
16444a8a | 176 | /** |
3d083395 | 177 | * clear_ftrace_function - reset the ftrace function |
16444a8a | 178 | * |
3d083395 SR |
179 | * This NULLs the ftrace function and in essence stops |
180 | * tracing. There may be lag | |
16444a8a | 181 | */ |
3d083395 | 182 | void clear_ftrace_function(void) |
16444a8a | 183 | { |
3d083395 | 184 | ftrace_trace_function = ftrace_stub; |
df4fc315 | 185 | ftrace_pid_function = ftrace_stub; |
3d083395 SR |
186 | } |
187 | ||
e248491a JO |
188 | static void control_ops_disable_all(struct ftrace_ops *ops) |
189 | { | |
190 | int cpu; | |
191 | ||
192 | for_each_possible_cpu(cpu) | |
193 | *per_cpu_ptr(ops->disabled, cpu) = 1; | |
194 | } | |
195 | ||
196 | static int control_ops_alloc(struct ftrace_ops *ops) | |
197 | { | |
198 | int __percpu *disabled; | |
199 | ||
200 | disabled = alloc_percpu(int); | |
201 | if (!disabled) | |
202 | return -ENOMEM; | |
203 | ||
204 | ops->disabled = disabled; | |
205 | control_ops_disable_all(ops); | |
206 | return 0; | |
207 | } | |
208 | ||
209 | static void control_ops_free(struct ftrace_ops *ops) | |
210 | { | |
211 | free_percpu(ops->disabled); | |
212 | } | |
213 | ||
2b499381 | 214 | static void update_global_ops(void) |
491d0dcf SR |
215 | { |
216 | ftrace_func_t func; | |
217 | ||
218 | /* | |
219 | * If there's only one function registered, then call that | |
220 | * function directly. Otherwise, we need to iterate over the | |
221 | * registered callers. | |
222 | */ | |
b848914c SR |
223 | if (ftrace_global_list == &ftrace_list_end || |
224 | ftrace_global_list->next == &ftrace_list_end) | |
225 | func = ftrace_global_list->func; | |
491d0dcf | 226 | else |
b848914c | 227 | func = ftrace_global_list_func; |
491d0dcf SR |
228 | |
229 | /* If we filter on pids, update to use the pid function */ | |
230 | if (!list_empty(&ftrace_pids)) { | |
231 | set_ftrace_pid_function(func); | |
232 | func = ftrace_pid_func; | |
233 | } | |
2b499381 SR |
234 | |
235 | global_ops.func = func; | |
236 | } | |
237 | ||
238 | static void update_ftrace_function(void) | |
239 | { | |
240 | ftrace_func_t func; | |
241 | ||
242 | update_global_ops(); | |
243 | ||
cdbe61bf SR |
244 | /* |
245 | * If we are at the end of the list and this ops is | |
4740974a SR |
246 | * recursion safe and not dynamic and the arch supports passing ops, |
247 | * then have the mcount trampoline call the function directly. | |
cdbe61bf | 248 | */ |
b848914c | 249 | if (ftrace_ops_list == &ftrace_list_end || |
cdbe61bf | 250 | (ftrace_ops_list->next == &ftrace_list_end && |
2f5f6ad9 | 251 | !(ftrace_ops_list->flags & FTRACE_OPS_FL_DYNAMIC) && |
4740974a | 252 | (ftrace_ops_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) && |
ccf3672d | 253 | !FTRACE_FORCE_LIST_FUNC)) { |
2f5f6ad9 SR |
254 | /* Set the ftrace_ops that the arch callback uses */ |
255 | if (ftrace_ops_list == &global_ops) | |
256 | function_trace_op = ftrace_global_list; | |
257 | else | |
258 | function_trace_op = ftrace_ops_list; | |
b848914c | 259 | func = ftrace_ops_list->func; |
2f5f6ad9 SR |
260 | } else { |
261 | /* Just use the default ftrace_ops */ | |
262 | function_trace_op = &ftrace_list_end; | |
b848914c | 263 | func = ftrace_ops_list_func; |
2f5f6ad9 | 264 | } |
2b499381 | 265 | |
491d0dcf | 266 | ftrace_trace_function = func; |
491d0dcf SR |
267 | } |
268 | ||
2b499381 | 269 | static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
3d083395 | 270 | { |
2b499381 | 271 | ops->next = *list; |
16444a8a | 272 | /* |
b848914c | 273 | * We are entering ops into the list but another |
16444a8a ACM |
274 | * CPU might be walking that list. We need to make sure |
275 | * the ops->next pointer is valid before another CPU sees | |
b848914c | 276 | * the ops pointer included into the list. |
16444a8a | 277 | */ |
2b499381 | 278 | rcu_assign_pointer(*list, ops); |
16444a8a ACM |
279 | } |
280 | ||
2b499381 | 281 | static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
16444a8a | 282 | { |
16444a8a | 283 | struct ftrace_ops **p; |
16444a8a ACM |
284 | |
285 | /* | |
3d083395 SR |
286 | * If we are removing the last function, then simply point |
287 | * to the ftrace_stub. | |
16444a8a | 288 | */ |
2b499381 SR |
289 | if (*list == ops && ops->next == &ftrace_list_end) { |
290 | *list = &ftrace_list_end; | |
e6ea44e9 | 291 | return 0; |
16444a8a ACM |
292 | } |
293 | ||
2b499381 | 294 | for (p = list; *p != &ftrace_list_end; p = &(*p)->next) |
16444a8a ACM |
295 | if (*p == ops) |
296 | break; | |
297 | ||
e6ea44e9 SR |
298 | if (*p != ops) |
299 | return -1; | |
16444a8a ACM |
300 | |
301 | *p = (*p)->next; | |
2b499381 SR |
302 | return 0; |
303 | } | |
16444a8a | 304 | |
e248491a JO |
305 | static void add_ftrace_list_ops(struct ftrace_ops **list, |
306 | struct ftrace_ops *main_ops, | |
307 | struct ftrace_ops *ops) | |
308 | { | |
309 | int first = *list == &ftrace_list_end; | |
310 | add_ftrace_ops(list, ops); | |
311 | if (first) | |
312 | add_ftrace_ops(&ftrace_ops_list, main_ops); | |
313 | } | |
314 | ||
315 | static int remove_ftrace_list_ops(struct ftrace_ops **list, | |
316 | struct ftrace_ops *main_ops, | |
317 | struct ftrace_ops *ops) | |
318 | { | |
319 | int ret = remove_ftrace_ops(list, ops); | |
320 | if (!ret && *list == &ftrace_list_end) | |
321 | ret = remove_ftrace_ops(&ftrace_ops_list, main_ops); | |
322 | return ret; | |
323 | } | |
324 | ||
2b499381 SR |
325 | static int __register_ftrace_function(struct ftrace_ops *ops) |
326 | { | |
8d240dd8 | 327 | if (unlikely(ftrace_disabled)) |
2b499381 SR |
328 | return -ENODEV; |
329 | ||
330 | if (FTRACE_WARN_ON(ops == &global_ops)) | |
331 | return -EINVAL; | |
332 | ||
b848914c SR |
333 | if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED)) |
334 | return -EBUSY; | |
335 | ||
e248491a JO |
336 | /* We don't support both control and global flags set. */ |
337 | if ((ops->flags & FL_GLOBAL_CONTROL_MASK) == FL_GLOBAL_CONTROL_MASK) | |
338 | return -EINVAL; | |
339 | ||
08f6fba5 SR |
340 | #ifndef ARCH_SUPPORTS_FTRACE_SAVE_REGS |
341 | /* | |
342 | * If the ftrace_ops specifies SAVE_REGS, then it only can be used | |
343 | * if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set. | |
344 | * Setting SAVE_REGS_IF_SUPPORTED makes SAVE_REGS irrelevant. | |
345 | */ | |
346 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS && | |
347 | !(ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)) | |
348 | return -EINVAL; | |
349 | ||
350 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED) | |
351 | ops->flags |= FTRACE_OPS_FL_SAVE_REGS; | |
352 | #endif | |
353 | ||
cdbe61bf SR |
354 | if (!core_kernel_data((unsigned long)ops)) |
355 | ops->flags |= FTRACE_OPS_FL_DYNAMIC; | |
356 | ||
b848914c | 357 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
e248491a | 358 | add_ftrace_list_ops(&ftrace_global_list, &global_ops, ops); |
b848914c | 359 | ops->flags |= FTRACE_OPS_FL_ENABLED; |
e248491a JO |
360 | } else if (ops->flags & FTRACE_OPS_FL_CONTROL) { |
361 | if (control_ops_alloc(ops)) | |
362 | return -ENOMEM; | |
363 | add_ftrace_list_ops(&ftrace_control_list, &control_ops, ops); | |
b848914c SR |
364 | } else |
365 | add_ftrace_ops(&ftrace_ops_list, ops); | |
366 | ||
2b499381 SR |
367 | if (ftrace_enabled) |
368 | update_ftrace_function(); | |
369 | ||
370 | return 0; | |
371 | } | |
372 | ||
373 | static int __unregister_ftrace_function(struct ftrace_ops *ops) | |
374 | { | |
375 | int ret; | |
376 | ||
377 | if (ftrace_disabled) | |
378 | return -ENODEV; | |
379 | ||
b848914c SR |
380 | if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) |
381 | return -EBUSY; | |
382 | ||
2b499381 SR |
383 | if (FTRACE_WARN_ON(ops == &global_ops)) |
384 | return -EINVAL; | |
385 | ||
b848914c | 386 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
e248491a JO |
387 | ret = remove_ftrace_list_ops(&ftrace_global_list, |
388 | &global_ops, ops); | |
b848914c SR |
389 | if (!ret) |
390 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; | |
e248491a JO |
391 | } else if (ops->flags & FTRACE_OPS_FL_CONTROL) { |
392 | ret = remove_ftrace_list_ops(&ftrace_control_list, | |
393 | &control_ops, ops); | |
394 | if (!ret) { | |
395 | /* | |
396 | * The ftrace_ops is now removed from the list, | |
397 | * so there'll be no new users. We must ensure | |
398 | * all current users are done before we free | |
399 | * the control data. | |
400 | */ | |
401 | synchronize_sched(); | |
402 | control_ops_free(ops); | |
403 | } | |
b848914c SR |
404 | } else |
405 | ret = remove_ftrace_ops(&ftrace_ops_list, ops); | |
406 | ||
2b499381 SR |
407 | if (ret < 0) |
408 | return ret; | |
b848914c | 409 | |
491d0dcf SR |
410 | if (ftrace_enabled) |
411 | update_ftrace_function(); | |
16444a8a | 412 | |
cdbe61bf SR |
413 | /* |
414 | * Dynamic ops may be freed, we must make sure that all | |
415 | * callers are done before leaving this function. | |
416 | */ | |
417 | if (ops->flags & FTRACE_OPS_FL_DYNAMIC) | |
418 | synchronize_sched(); | |
419 | ||
e6ea44e9 | 420 | return 0; |
3d083395 SR |
421 | } |
422 | ||
df4fc315 SR |
423 | static void ftrace_update_pid_func(void) |
424 | { | |
491d0dcf | 425 | /* Only do something if we are tracing something */ |
df4fc315 | 426 | if (ftrace_trace_function == ftrace_stub) |
10dd3ebe | 427 | return; |
df4fc315 | 428 | |
491d0dcf | 429 | update_ftrace_function(); |
df4fc315 SR |
430 | } |
431 | ||
493762fc SR |
432 | #ifdef CONFIG_FUNCTION_PROFILER |
433 | struct ftrace_profile { | |
434 | struct hlist_node node; | |
435 | unsigned long ip; | |
436 | unsigned long counter; | |
0706f1c4 SR |
437 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
438 | unsigned long long time; | |
e330b3bc | 439 | unsigned long long time_squared; |
0706f1c4 | 440 | #endif |
8fc0c701 SR |
441 | }; |
442 | ||
493762fc SR |
443 | struct ftrace_profile_page { |
444 | struct ftrace_profile_page *next; | |
445 | unsigned long index; | |
446 | struct ftrace_profile records[]; | |
d61f82d0 SR |
447 | }; |
448 | ||
cafb168a SR |
449 | struct ftrace_profile_stat { |
450 | atomic_t disabled; | |
451 | struct hlist_head *hash; | |
452 | struct ftrace_profile_page *pages; | |
453 | struct ftrace_profile_page *start; | |
454 | struct tracer_stat stat; | |
455 | }; | |
456 | ||
493762fc SR |
457 | #define PROFILE_RECORDS_SIZE \ |
458 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | |
5072c59f | 459 | |
493762fc SR |
460 | #define PROFILES_PER_PAGE \ |
461 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | |
3d083395 | 462 | |
fb9fb015 SR |
463 | static int ftrace_profile_bits __read_mostly; |
464 | static int ftrace_profile_enabled __read_mostly; | |
465 | ||
466 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ | |
bac429f0 SR |
467 | static DEFINE_MUTEX(ftrace_profile_lock); |
468 | ||
cafb168a | 469 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); |
493762fc SR |
470 | |
471 | #define FTRACE_PROFILE_HASH_SIZE 1024 /* must be power of 2 */ | |
472 | ||
bac429f0 SR |
473 | static void * |
474 | function_stat_next(void *v, int idx) | |
475 | { | |
493762fc SR |
476 | struct ftrace_profile *rec = v; |
477 | struct ftrace_profile_page *pg; | |
bac429f0 | 478 | |
493762fc | 479 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
bac429f0 SR |
480 | |
481 | again: | |
0296e425 LZ |
482 | if (idx != 0) |
483 | rec++; | |
484 | ||
bac429f0 SR |
485 | if ((void *)rec >= (void *)&pg->records[pg->index]) { |
486 | pg = pg->next; | |
487 | if (!pg) | |
488 | return NULL; | |
489 | rec = &pg->records[0]; | |
493762fc SR |
490 | if (!rec->counter) |
491 | goto again; | |
bac429f0 SR |
492 | } |
493 | ||
bac429f0 SR |
494 | return rec; |
495 | } | |
496 | ||
497 | static void *function_stat_start(struct tracer_stat *trace) | |
498 | { | |
cafb168a SR |
499 | struct ftrace_profile_stat *stat = |
500 | container_of(trace, struct ftrace_profile_stat, stat); | |
501 | ||
502 | if (!stat || !stat->start) | |
503 | return NULL; | |
504 | ||
505 | return function_stat_next(&stat->start->records[0], 0); | |
bac429f0 SR |
506 | } |
507 | ||
0706f1c4 SR |
508 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
509 | /* function graph compares on total time */ | |
510 | static int function_stat_cmp(void *p1, void *p2) | |
511 | { | |
512 | struct ftrace_profile *a = p1; | |
513 | struct ftrace_profile *b = p2; | |
514 | ||
515 | if (a->time < b->time) | |
516 | return -1; | |
517 | if (a->time > b->time) | |
518 | return 1; | |
519 | else | |
520 | return 0; | |
521 | } | |
522 | #else | |
523 | /* not function graph compares against hits */ | |
bac429f0 SR |
524 | static int function_stat_cmp(void *p1, void *p2) |
525 | { | |
493762fc SR |
526 | struct ftrace_profile *a = p1; |
527 | struct ftrace_profile *b = p2; | |
bac429f0 SR |
528 | |
529 | if (a->counter < b->counter) | |
530 | return -1; | |
531 | if (a->counter > b->counter) | |
532 | return 1; | |
533 | else | |
534 | return 0; | |
535 | } | |
0706f1c4 | 536 | #endif |
bac429f0 SR |
537 | |
538 | static int function_stat_headers(struct seq_file *m) | |
539 | { | |
0706f1c4 | 540 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b | 541 | seq_printf(m, " Function " |
e330b3bc | 542 | "Hit Time Avg s^2\n" |
34886c8b | 543 | " -------- " |
e330b3bc | 544 | "--- ---- --- ---\n"); |
0706f1c4 | 545 | #else |
bac429f0 SR |
546 | seq_printf(m, " Function Hit\n" |
547 | " -------- ---\n"); | |
0706f1c4 | 548 | #endif |
bac429f0 SR |
549 | return 0; |
550 | } | |
551 | ||
552 | static int function_stat_show(struct seq_file *m, void *v) | |
553 | { | |
493762fc | 554 | struct ftrace_profile *rec = v; |
bac429f0 | 555 | char str[KSYM_SYMBOL_LEN]; |
3aaba20f | 556 | int ret = 0; |
0706f1c4 | 557 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b SR |
558 | static struct trace_seq s; |
559 | unsigned long long avg; | |
e330b3bc | 560 | unsigned long long stddev; |
0706f1c4 | 561 | #endif |
3aaba20f LZ |
562 | mutex_lock(&ftrace_profile_lock); |
563 | ||
564 | /* we raced with function_profile_reset() */ | |
565 | if (unlikely(rec->counter == 0)) { | |
566 | ret = -EBUSY; | |
567 | goto out; | |
568 | } | |
bac429f0 SR |
569 | |
570 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
0706f1c4 SR |
571 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); |
572 | ||
573 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
574 | seq_printf(m, " "); | |
34886c8b SR |
575 | avg = rec->time; |
576 | do_div(avg, rec->counter); | |
577 | ||
e330b3bc CD |
578 | /* Sample standard deviation (s^2) */ |
579 | if (rec->counter <= 1) | |
580 | stddev = 0; | |
581 | else { | |
582 | stddev = rec->time_squared - rec->counter * avg * avg; | |
583 | /* | |
584 | * Divide only 1000 for ns^2 -> us^2 conversion. | |
585 | * trace_print_graph_duration will divide 1000 again. | |
586 | */ | |
587 | do_div(stddev, (rec->counter - 1) * 1000); | |
588 | } | |
589 | ||
34886c8b SR |
590 | trace_seq_init(&s); |
591 | trace_print_graph_duration(rec->time, &s); | |
592 | trace_seq_puts(&s, " "); | |
593 | trace_print_graph_duration(avg, &s); | |
e330b3bc CD |
594 | trace_seq_puts(&s, " "); |
595 | trace_print_graph_duration(stddev, &s); | |
0706f1c4 | 596 | trace_print_seq(m, &s); |
0706f1c4 SR |
597 | #endif |
598 | seq_putc(m, '\n'); | |
3aaba20f LZ |
599 | out: |
600 | mutex_unlock(&ftrace_profile_lock); | |
bac429f0 | 601 | |
3aaba20f | 602 | return ret; |
bac429f0 SR |
603 | } |
604 | ||
cafb168a | 605 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) |
bac429f0 | 606 | { |
493762fc | 607 | struct ftrace_profile_page *pg; |
bac429f0 | 608 | |
cafb168a | 609 | pg = stat->pages = stat->start; |
bac429f0 | 610 | |
493762fc SR |
611 | while (pg) { |
612 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | |
613 | pg->index = 0; | |
614 | pg = pg->next; | |
bac429f0 SR |
615 | } |
616 | ||
cafb168a | 617 | memset(stat->hash, 0, |
493762fc SR |
618 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); |
619 | } | |
bac429f0 | 620 | |
cafb168a | 621 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) |
493762fc SR |
622 | { |
623 | struct ftrace_profile_page *pg; | |
318e0a73 SR |
624 | int functions; |
625 | int pages; | |
493762fc | 626 | int i; |
bac429f0 | 627 | |
493762fc | 628 | /* If we already allocated, do nothing */ |
cafb168a | 629 | if (stat->pages) |
493762fc | 630 | return 0; |
bac429f0 | 631 | |
cafb168a SR |
632 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); |
633 | if (!stat->pages) | |
493762fc | 634 | return -ENOMEM; |
bac429f0 | 635 | |
318e0a73 SR |
636 | #ifdef CONFIG_DYNAMIC_FTRACE |
637 | functions = ftrace_update_tot_cnt; | |
638 | #else | |
639 | /* | |
640 | * We do not know the number of functions that exist because | |
641 | * dynamic tracing is what counts them. With past experience | |
642 | * we have around 20K functions. That should be more than enough. | |
643 | * It is highly unlikely we will execute every function in | |
644 | * the kernel. | |
645 | */ | |
646 | functions = 20000; | |
647 | #endif | |
648 | ||
cafb168a | 649 | pg = stat->start = stat->pages; |
bac429f0 | 650 | |
318e0a73 SR |
651 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); |
652 | ||
653 | for (i = 0; i < pages; i++) { | |
493762fc | 654 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
493762fc | 655 | if (!pg->next) |
318e0a73 | 656 | goto out_free; |
493762fc SR |
657 | pg = pg->next; |
658 | } | |
659 | ||
660 | return 0; | |
318e0a73 SR |
661 | |
662 | out_free: | |
663 | pg = stat->start; | |
664 | while (pg) { | |
665 | unsigned long tmp = (unsigned long)pg; | |
666 | ||
667 | pg = pg->next; | |
668 | free_page(tmp); | |
669 | } | |
670 | ||
671 | free_page((unsigned long)stat->pages); | |
672 | stat->pages = NULL; | |
673 | stat->start = NULL; | |
674 | ||
675 | return -ENOMEM; | |
bac429f0 SR |
676 | } |
677 | ||
cafb168a | 678 | static int ftrace_profile_init_cpu(int cpu) |
bac429f0 | 679 | { |
cafb168a | 680 | struct ftrace_profile_stat *stat; |
493762fc | 681 | int size; |
bac429f0 | 682 | |
cafb168a SR |
683 | stat = &per_cpu(ftrace_profile_stats, cpu); |
684 | ||
685 | if (stat->hash) { | |
493762fc | 686 | /* If the profile is already created, simply reset it */ |
cafb168a | 687 | ftrace_profile_reset(stat); |
493762fc SR |
688 | return 0; |
689 | } | |
bac429f0 | 690 | |
493762fc SR |
691 | /* |
692 | * We are profiling all functions, but usually only a few thousand | |
693 | * functions are hit. We'll make a hash of 1024 items. | |
694 | */ | |
695 | size = FTRACE_PROFILE_HASH_SIZE; | |
bac429f0 | 696 | |
cafb168a | 697 | stat->hash = kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL); |
493762fc | 698 | |
cafb168a | 699 | if (!stat->hash) |
493762fc SR |
700 | return -ENOMEM; |
701 | ||
cafb168a SR |
702 | if (!ftrace_profile_bits) { |
703 | size--; | |
493762fc | 704 | |
cafb168a SR |
705 | for (; size; size >>= 1) |
706 | ftrace_profile_bits++; | |
707 | } | |
493762fc | 708 | |
318e0a73 | 709 | /* Preallocate the function profiling pages */ |
cafb168a SR |
710 | if (ftrace_profile_pages_init(stat) < 0) { |
711 | kfree(stat->hash); | |
712 | stat->hash = NULL; | |
493762fc SR |
713 | return -ENOMEM; |
714 | } | |
715 | ||
716 | return 0; | |
bac429f0 SR |
717 | } |
718 | ||
cafb168a SR |
719 | static int ftrace_profile_init(void) |
720 | { | |
721 | int cpu; | |
722 | int ret = 0; | |
723 | ||
724 | for_each_online_cpu(cpu) { | |
725 | ret = ftrace_profile_init_cpu(cpu); | |
726 | if (ret) | |
727 | break; | |
728 | } | |
729 | ||
730 | return ret; | |
731 | } | |
732 | ||
493762fc | 733 | /* interrupts must be disabled */ |
cafb168a SR |
734 | static struct ftrace_profile * |
735 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) | |
bac429f0 | 736 | { |
493762fc | 737 | struct ftrace_profile *rec; |
bac429f0 SR |
738 | struct hlist_head *hhd; |
739 | struct hlist_node *n; | |
bac429f0 SR |
740 | unsigned long key; |
741 | ||
bac429f0 | 742 | key = hash_long(ip, ftrace_profile_bits); |
cafb168a | 743 | hhd = &stat->hash[key]; |
bac429f0 SR |
744 | |
745 | if (hlist_empty(hhd)) | |
746 | return NULL; | |
747 | ||
bac429f0 SR |
748 | hlist_for_each_entry_rcu(rec, n, hhd, node) { |
749 | if (rec->ip == ip) | |
493762fc SR |
750 | return rec; |
751 | } | |
752 | ||
753 | return NULL; | |
754 | } | |
755 | ||
cafb168a SR |
756 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, |
757 | struct ftrace_profile *rec) | |
493762fc SR |
758 | { |
759 | unsigned long key; | |
760 | ||
761 | key = hash_long(rec->ip, ftrace_profile_bits); | |
cafb168a | 762 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); |
493762fc SR |
763 | } |
764 | ||
318e0a73 SR |
765 | /* |
766 | * The memory is already allocated, this simply finds a new record to use. | |
767 | */ | |
493762fc | 768 | static struct ftrace_profile * |
318e0a73 | 769 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) |
493762fc SR |
770 | { |
771 | struct ftrace_profile *rec = NULL; | |
772 | ||
318e0a73 | 773 | /* prevent recursion (from NMIs) */ |
cafb168a | 774 | if (atomic_inc_return(&stat->disabled) != 1) |
493762fc SR |
775 | goto out; |
776 | ||
493762fc | 777 | /* |
318e0a73 SR |
778 | * Try to find the function again since an NMI |
779 | * could have added it | |
493762fc | 780 | */ |
cafb168a | 781 | rec = ftrace_find_profiled_func(stat, ip); |
493762fc | 782 | if (rec) |
cafb168a | 783 | goto out; |
493762fc | 784 | |
cafb168a SR |
785 | if (stat->pages->index == PROFILES_PER_PAGE) { |
786 | if (!stat->pages->next) | |
787 | goto out; | |
788 | stat->pages = stat->pages->next; | |
bac429f0 | 789 | } |
493762fc | 790 | |
cafb168a | 791 | rec = &stat->pages->records[stat->pages->index++]; |
493762fc | 792 | rec->ip = ip; |
cafb168a | 793 | ftrace_add_profile(stat, rec); |
493762fc | 794 | |
bac429f0 | 795 | out: |
cafb168a | 796 | atomic_dec(&stat->disabled); |
bac429f0 SR |
797 | |
798 | return rec; | |
799 | } | |
800 | ||
801 | static void | |
2f5f6ad9 | 802 | function_profile_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 803 | struct ftrace_ops *ops, struct pt_regs *regs) |
bac429f0 | 804 | { |
cafb168a | 805 | struct ftrace_profile_stat *stat; |
493762fc | 806 | struct ftrace_profile *rec; |
bac429f0 SR |
807 | unsigned long flags; |
808 | ||
809 | if (!ftrace_profile_enabled) | |
810 | return; | |
811 | ||
812 | local_irq_save(flags); | |
cafb168a SR |
813 | |
814 | stat = &__get_cpu_var(ftrace_profile_stats); | |
0f6ce3de | 815 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
816 | goto out; |
817 | ||
818 | rec = ftrace_find_profiled_func(stat, ip); | |
493762fc | 819 | if (!rec) { |
318e0a73 | 820 | rec = ftrace_profile_alloc(stat, ip); |
493762fc SR |
821 | if (!rec) |
822 | goto out; | |
823 | } | |
bac429f0 SR |
824 | |
825 | rec->counter++; | |
826 | out: | |
827 | local_irq_restore(flags); | |
828 | } | |
829 | ||
0706f1c4 SR |
830 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
831 | static int profile_graph_entry(struct ftrace_graph_ent *trace) | |
832 | { | |
a1e2e31d | 833 | function_profile_call(trace->func, 0, NULL, NULL); |
0706f1c4 SR |
834 | return 1; |
835 | } | |
836 | ||
837 | static void profile_graph_return(struct ftrace_graph_ret *trace) | |
838 | { | |
cafb168a | 839 | struct ftrace_profile_stat *stat; |
a2a16d6a | 840 | unsigned long long calltime; |
0706f1c4 | 841 | struct ftrace_profile *rec; |
cafb168a | 842 | unsigned long flags; |
0706f1c4 SR |
843 | |
844 | local_irq_save(flags); | |
cafb168a | 845 | stat = &__get_cpu_var(ftrace_profile_stats); |
0f6ce3de | 846 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
847 | goto out; |
848 | ||
37e44bc5 SR |
849 | /* If the calltime was zero'd ignore it */ |
850 | if (!trace->calltime) | |
851 | goto out; | |
852 | ||
a2a16d6a SR |
853 | calltime = trace->rettime - trace->calltime; |
854 | ||
855 | if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) { | |
856 | int index; | |
857 | ||
858 | index = trace->depth; | |
859 | ||
860 | /* Append this call time to the parent time to subtract */ | |
861 | if (index) | |
862 | current->ret_stack[index - 1].subtime += calltime; | |
863 | ||
864 | if (current->ret_stack[index].subtime < calltime) | |
865 | calltime -= current->ret_stack[index].subtime; | |
866 | else | |
867 | calltime = 0; | |
868 | } | |
869 | ||
cafb168a | 870 | rec = ftrace_find_profiled_func(stat, trace->func); |
e330b3bc | 871 | if (rec) { |
a2a16d6a | 872 | rec->time += calltime; |
e330b3bc CD |
873 | rec->time_squared += calltime * calltime; |
874 | } | |
a2a16d6a | 875 | |
cafb168a | 876 | out: |
0706f1c4 SR |
877 | local_irq_restore(flags); |
878 | } | |
879 | ||
880 | static int register_ftrace_profiler(void) | |
881 | { | |
882 | return register_ftrace_graph(&profile_graph_return, | |
883 | &profile_graph_entry); | |
884 | } | |
885 | ||
886 | static void unregister_ftrace_profiler(void) | |
887 | { | |
888 | unregister_ftrace_graph(); | |
889 | } | |
890 | #else | |
bd38c0e6 | 891 | static struct ftrace_ops ftrace_profile_ops __read_mostly = { |
fb9fb015 | 892 | .func = function_profile_call, |
4740974a | 893 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
bac429f0 SR |
894 | }; |
895 | ||
0706f1c4 SR |
896 | static int register_ftrace_profiler(void) |
897 | { | |
898 | return register_ftrace_function(&ftrace_profile_ops); | |
899 | } | |
900 | ||
901 | static void unregister_ftrace_profiler(void) | |
902 | { | |
903 | unregister_ftrace_function(&ftrace_profile_ops); | |
904 | } | |
905 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
906 | ||
bac429f0 SR |
907 | static ssize_t |
908 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | |
909 | size_t cnt, loff_t *ppos) | |
910 | { | |
911 | unsigned long val; | |
bac429f0 SR |
912 | int ret; |
913 | ||
22fe9b54 PH |
914 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
915 | if (ret) | |
bac429f0 SR |
916 | return ret; |
917 | ||
918 | val = !!val; | |
919 | ||
920 | mutex_lock(&ftrace_profile_lock); | |
921 | if (ftrace_profile_enabled ^ val) { | |
922 | if (val) { | |
493762fc SR |
923 | ret = ftrace_profile_init(); |
924 | if (ret < 0) { | |
925 | cnt = ret; | |
926 | goto out; | |
927 | } | |
928 | ||
0706f1c4 SR |
929 | ret = register_ftrace_profiler(); |
930 | if (ret < 0) { | |
931 | cnt = ret; | |
932 | goto out; | |
933 | } | |
bac429f0 SR |
934 | ftrace_profile_enabled = 1; |
935 | } else { | |
936 | ftrace_profile_enabled = 0; | |
0f6ce3de SR |
937 | /* |
938 | * unregister_ftrace_profiler calls stop_machine | |
939 | * so this acts like an synchronize_sched. | |
940 | */ | |
0706f1c4 | 941 | unregister_ftrace_profiler(); |
bac429f0 SR |
942 | } |
943 | } | |
493762fc | 944 | out: |
bac429f0 SR |
945 | mutex_unlock(&ftrace_profile_lock); |
946 | ||
cf8517cf | 947 | *ppos += cnt; |
bac429f0 SR |
948 | |
949 | return cnt; | |
950 | } | |
951 | ||
493762fc SR |
952 | static ssize_t |
953 | ftrace_profile_read(struct file *filp, char __user *ubuf, | |
954 | size_t cnt, loff_t *ppos) | |
955 | { | |
fb9fb015 | 956 | char buf[64]; /* big enough to hold a number */ |
493762fc SR |
957 | int r; |
958 | ||
959 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | |
960 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
961 | } | |
962 | ||
bac429f0 SR |
963 | static const struct file_operations ftrace_profile_fops = { |
964 | .open = tracing_open_generic, | |
965 | .read = ftrace_profile_read, | |
966 | .write = ftrace_profile_write, | |
6038f373 | 967 | .llseek = default_llseek, |
bac429f0 SR |
968 | }; |
969 | ||
cafb168a SR |
970 | /* used to initialize the real stat files */ |
971 | static struct tracer_stat function_stats __initdata = { | |
fb9fb015 SR |
972 | .name = "functions", |
973 | .stat_start = function_stat_start, | |
974 | .stat_next = function_stat_next, | |
975 | .stat_cmp = function_stat_cmp, | |
976 | .stat_headers = function_stat_headers, | |
977 | .stat_show = function_stat_show | |
cafb168a SR |
978 | }; |
979 | ||
6ab5d668 | 980 | static __init void ftrace_profile_debugfs(struct dentry *d_tracer) |
bac429f0 | 981 | { |
cafb168a | 982 | struct ftrace_profile_stat *stat; |
bac429f0 | 983 | struct dentry *entry; |
cafb168a | 984 | char *name; |
bac429f0 | 985 | int ret; |
cafb168a SR |
986 | int cpu; |
987 | ||
988 | for_each_possible_cpu(cpu) { | |
989 | stat = &per_cpu(ftrace_profile_stats, cpu); | |
990 | ||
991 | /* allocate enough for function name + cpu number */ | |
992 | name = kmalloc(32, GFP_KERNEL); | |
993 | if (!name) { | |
994 | /* | |
995 | * The files created are permanent, if something happens | |
996 | * we still do not free memory. | |
997 | */ | |
cafb168a SR |
998 | WARN(1, |
999 | "Could not allocate stat file for cpu %d\n", | |
1000 | cpu); | |
1001 | return; | |
1002 | } | |
1003 | stat->stat = function_stats; | |
1004 | snprintf(name, 32, "function%d", cpu); | |
1005 | stat->stat.name = name; | |
1006 | ret = register_stat_tracer(&stat->stat); | |
1007 | if (ret) { | |
1008 | WARN(1, | |
1009 | "Could not register function stat for cpu %d\n", | |
1010 | cpu); | |
1011 | kfree(name); | |
1012 | return; | |
1013 | } | |
bac429f0 SR |
1014 | } |
1015 | ||
1016 | entry = debugfs_create_file("function_profile_enabled", 0644, | |
1017 | d_tracer, NULL, &ftrace_profile_fops); | |
1018 | if (!entry) | |
1019 | pr_warning("Could not create debugfs " | |
1020 | "'function_profile_enabled' entry\n"); | |
1021 | } | |
1022 | ||
bac429f0 | 1023 | #else /* CONFIG_FUNCTION_PROFILER */ |
6ab5d668 | 1024 | static __init void ftrace_profile_debugfs(struct dentry *d_tracer) |
bac429f0 SR |
1025 | { |
1026 | } | |
bac429f0 SR |
1027 | #endif /* CONFIG_FUNCTION_PROFILER */ |
1028 | ||
493762fc SR |
1029 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; |
1030 | ||
1031 | #ifdef CONFIG_DYNAMIC_FTRACE | |
1032 | ||
1033 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD | |
1034 | # error Dynamic ftrace depends on MCOUNT_RECORD | |
1035 | #endif | |
1036 | ||
1037 | static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly; | |
1038 | ||
1039 | struct ftrace_func_probe { | |
1040 | struct hlist_node node; | |
1041 | struct ftrace_probe_ops *ops; | |
1042 | unsigned long flags; | |
1043 | unsigned long ip; | |
1044 | void *data; | |
1045 | struct rcu_head rcu; | |
1046 | }; | |
1047 | ||
b448c4e3 SR |
1048 | struct ftrace_func_entry { |
1049 | struct hlist_node hlist; | |
1050 | unsigned long ip; | |
1051 | }; | |
1052 | ||
1053 | struct ftrace_hash { | |
1054 | unsigned long size_bits; | |
1055 | struct hlist_head *buckets; | |
1056 | unsigned long count; | |
07fd5515 | 1057 | struct rcu_head rcu; |
b448c4e3 SR |
1058 | }; |
1059 | ||
33dc9b12 SR |
1060 | /* |
1061 | * We make these constant because no one should touch them, | |
1062 | * but they are used as the default "empty hash", to avoid allocating | |
1063 | * it all the time. These are in a read only section such that if | |
1064 | * anyone does try to modify it, it will cause an exception. | |
1065 | */ | |
1066 | static const struct hlist_head empty_buckets[1]; | |
1067 | static const struct ftrace_hash empty_hash = { | |
1068 | .buckets = (struct hlist_head *)empty_buckets, | |
1cf41dd7 | 1069 | }; |
33dc9b12 | 1070 | #define EMPTY_HASH ((struct ftrace_hash *)&empty_hash) |
493762fc | 1071 | |
2b499381 | 1072 | static struct ftrace_ops global_ops = { |
f45948e8 | 1073 | .func = ftrace_stub, |
33dc9b12 SR |
1074 | .notrace_hash = EMPTY_HASH, |
1075 | .filter_hash = EMPTY_HASH, | |
4740974a | 1076 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
f45948e8 SR |
1077 | }; |
1078 | ||
493762fc SR |
1079 | static DEFINE_MUTEX(ftrace_regex_lock); |
1080 | ||
1081 | struct ftrace_page { | |
1082 | struct ftrace_page *next; | |
a7900875 | 1083 | struct dyn_ftrace *records; |
493762fc | 1084 | int index; |
a7900875 | 1085 | int size; |
493762fc SR |
1086 | }; |
1087 | ||
85ae32ae SR |
1088 | static struct ftrace_page *ftrace_new_pgs; |
1089 | ||
a7900875 SR |
1090 | #define ENTRY_SIZE sizeof(struct dyn_ftrace) |
1091 | #define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE) | |
493762fc SR |
1092 | |
1093 | /* estimate from running different kernels */ | |
1094 | #define NR_TO_INIT 10000 | |
1095 | ||
1096 | static struct ftrace_page *ftrace_pages_start; | |
1097 | static struct ftrace_page *ftrace_pages; | |
1098 | ||
06a51d93 SR |
1099 | static bool ftrace_hash_empty(struct ftrace_hash *hash) |
1100 | { | |
1101 | return !hash || !hash->count; | |
1102 | } | |
1103 | ||
b448c4e3 SR |
1104 | static struct ftrace_func_entry * |
1105 | ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
1106 | { | |
1107 | unsigned long key; | |
1108 | struct ftrace_func_entry *entry; | |
1109 | struct hlist_head *hhd; | |
1110 | struct hlist_node *n; | |
1111 | ||
06a51d93 | 1112 | if (ftrace_hash_empty(hash)) |
b448c4e3 SR |
1113 | return NULL; |
1114 | ||
1115 | if (hash->size_bits > 0) | |
1116 | key = hash_long(ip, hash->size_bits); | |
1117 | else | |
1118 | key = 0; | |
1119 | ||
1120 | hhd = &hash->buckets[key]; | |
1121 | ||
1122 | hlist_for_each_entry_rcu(entry, n, hhd, hlist) { | |
1123 | if (entry->ip == ip) | |
1124 | return entry; | |
1125 | } | |
1126 | return NULL; | |
1127 | } | |
1128 | ||
33dc9b12 SR |
1129 | static void __add_hash_entry(struct ftrace_hash *hash, |
1130 | struct ftrace_func_entry *entry) | |
b448c4e3 | 1131 | { |
b448c4e3 SR |
1132 | struct hlist_head *hhd; |
1133 | unsigned long key; | |
1134 | ||
b448c4e3 | 1135 | if (hash->size_bits) |
33dc9b12 | 1136 | key = hash_long(entry->ip, hash->size_bits); |
b448c4e3 SR |
1137 | else |
1138 | key = 0; | |
1139 | ||
b448c4e3 SR |
1140 | hhd = &hash->buckets[key]; |
1141 | hlist_add_head(&entry->hlist, hhd); | |
1142 | hash->count++; | |
33dc9b12 SR |
1143 | } |
1144 | ||
1145 | static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) | |
1146 | { | |
1147 | struct ftrace_func_entry *entry; | |
1148 | ||
1149 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
1150 | if (!entry) | |
1151 | return -ENOMEM; | |
1152 | ||
1153 | entry->ip = ip; | |
1154 | __add_hash_entry(hash, entry); | |
b448c4e3 SR |
1155 | |
1156 | return 0; | |
1157 | } | |
1158 | ||
1159 | static void | |
33dc9b12 | 1160 | free_hash_entry(struct ftrace_hash *hash, |
b448c4e3 SR |
1161 | struct ftrace_func_entry *entry) |
1162 | { | |
1163 | hlist_del(&entry->hlist); | |
1164 | kfree(entry); | |
1165 | hash->count--; | |
1166 | } | |
1167 | ||
33dc9b12 SR |
1168 | static void |
1169 | remove_hash_entry(struct ftrace_hash *hash, | |
1170 | struct ftrace_func_entry *entry) | |
1171 | { | |
1172 | hlist_del(&entry->hlist); | |
1173 | hash->count--; | |
1174 | } | |
1175 | ||
b448c4e3 SR |
1176 | static void ftrace_hash_clear(struct ftrace_hash *hash) |
1177 | { | |
1178 | struct hlist_head *hhd; | |
1179 | struct hlist_node *tp, *tn; | |
1180 | struct ftrace_func_entry *entry; | |
1181 | int size = 1 << hash->size_bits; | |
1182 | int i; | |
1183 | ||
33dc9b12 SR |
1184 | if (!hash->count) |
1185 | return; | |
1186 | ||
b448c4e3 SR |
1187 | for (i = 0; i < size; i++) { |
1188 | hhd = &hash->buckets[i]; | |
1189 | hlist_for_each_entry_safe(entry, tp, tn, hhd, hlist) | |
33dc9b12 | 1190 | free_hash_entry(hash, entry); |
b448c4e3 SR |
1191 | } |
1192 | FTRACE_WARN_ON(hash->count); | |
1193 | } | |
1194 | ||
33dc9b12 SR |
1195 | static void free_ftrace_hash(struct ftrace_hash *hash) |
1196 | { | |
1197 | if (!hash || hash == EMPTY_HASH) | |
1198 | return; | |
1199 | ftrace_hash_clear(hash); | |
1200 | kfree(hash->buckets); | |
1201 | kfree(hash); | |
1202 | } | |
1203 | ||
07fd5515 SR |
1204 | static void __free_ftrace_hash_rcu(struct rcu_head *rcu) |
1205 | { | |
1206 | struct ftrace_hash *hash; | |
1207 | ||
1208 | hash = container_of(rcu, struct ftrace_hash, rcu); | |
1209 | free_ftrace_hash(hash); | |
1210 | } | |
1211 | ||
1212 | static void free_ftrace_hash_rcu(struct ftrace_hash *hash) | |
1213 | { | |
1214 | if (!hash || hash == EMPTY_HASH) | |
1215 | return; | |
1216 | call_rcu_sched(&hash->rcu, __free_ftrace_hash_rcu); | |
1217 | } | |
1218 | ||
5500fa51 JO |
1219 | void ftrace_free_filter(struct ftrace_ops *ops) |
1220 | { | |
1221 | free_ftrace_hash(ops->filter_hash); | |
1222 | free_ftrace_hash(ops->notrace_hash); | |
1223 | } | |
1224 | ||
33dc9b12 SR |
1225 | static struct ftrace_hash *alloc_ftrace_hash(int size_bits) |
1226 | { | |
1227 | struct ftrace_hash *hash; | |
1228 | int size; | |
1229 | ||
1230 | hash = kzalloc(sizeof(*hash), GFP_KERNEL); | |
1231 | if (!hash) | |
1232 | return NULL; | |
1233 | ||
1234 | size = 1 << size_bits; | |
47b0edcb | 1235 | hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL); |
33dc9b12 SR |
1236 | |
1237 | if (!hash->buckets) { | |
1238 | kfree(hash); | |
1239 | return NULL; | |
1240 | } | |
1241 | ||
1242 | hash->size_bits = size_bits; | |
1243 | ||
1244 | return hash; | |
1245 | } | |
1246 | ||
1247 | static struct ftrace_hash * | |
1248 | alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) | |
1249 | { | |
1250 | struct ftrace_func_entry *entry; | |
1251 | struct ftrace_hash *new_hash; | |
1252 | struct hlist_node *tp; | |
1253 | int size; | |
1254 | int ret; | |
1255 | int i; | |
1256 | ||
1257 | new_hash = alloc_ftrace_hash(size_bits); | |
1258 | if (!new_hash) | |
1259 | return NULL; | |
1260 | ||
1261 | /* Empty hash? */ | |
06a51d93 | 1262 | if (ftrace_hash_empty(hash)) |
33dc9b12 SR |
1263 | return new_hash; |
1264 | ||
1265 | size = 1 << hash->size_bits; | |
1266 | for (i = 0; i < size; i++) { | |
1267 | hlist_for_each_entry(entry, tp, &hash->buckets[i], hlist) { | |
1268 | ret = add_hash_entry(new_hash, entry->ip); | |
1269 | if (ret < 0) | |
1270 | goto free_hash; | |
1271 | } | |
1272 | } | |
1273 | ||
1274 | FTRACE_WARN_ON(new_hash->count != hash->count); | |
1275 | ||
1276 | return new_hash; | |
1277 | ||
1278 | free_hash: | |
1279 | free_ftrace_hash(new_hash); | |
1280 | return NULL; | |
1281 | } | |
1282 | ||
41fb61c2 SR |
1283 | static void |
1284 | ftrace_hash_rec_disable(struct ftrace_ops *ops, int filter_hash); | |
1285 | static void | |
1286 | ftrace_hash_rec_enable(struct ftrace_ops *ops, int filter_hash); | |
1287 | ||
33dc9b12 | 1288 | static int |
41fb61c2 SR |
1289 | ftrace_hash_move(struct ftrace_ops *ops, int enable, |
1290 | struct ftrace_hash **dst, struct ftrace_hash *src) | |
33dc9b12 SR |
1291 | { |
1292 | struct ftrace_func_entry *entry; | |
1293 | struct hlist_node *tp, *tn; | |
1294 | struct hlist_head *hhd; | |
07fd5515 SR |
1295 | struct ftrace_hash *old_hash; |
1296 | struct ftrace_hash *new_hash; | |
33dc9b12 SR |
1297 | unsigned long key; |
1298 | int size = src->count; | |
1299 | int bits = 0; | |
41fb61c2 | 1300 | int ret; |
33dc9b12 SR |
1301 | int i; |
1302 | ||
41fb61c2 SR |
1303 | /* |
1304 | * Remove the current set, update the hash and add | |
1305 | * them back. | |
1306 | */ | |
1307 | ftrace_hash_rec_disable(ops, enable); | |
1308 | ||
33dc9b12 SR |
1309 | /* |
1310 | * If the new source is empty, just free dst and assign it | |
1311 | * the empty_hash. | |
1312 | */ | |
1313 | if (!src->count) { | |
07fd5515 SR |
1314 | free_ftrace_hash_rcu(*dst); |
1315 | rcu_assign_pointer(*dst, EMPTY_HASH); | |
d4d34b98 SR |
1316 | /* still need to update the function records */ |
1317 | ret = 0; | |
1318 | goto out; | |
33dc9b12 SR |
1319 | } |
1320 | ||
33dc9b12 SR |
1321 | /* |
1322 | * Make the hash size about 1/2 the # found | |
1323 | */ | |
1324 | for (size /= 2; size; size >>= 1) | |
1325 | bits++; | |
1326 | ||
1327 | /* Don't allocate too much */ | |
1328 | if (bits > FTRACE_HASH_MAX_BITS) | |
1329 | bits = FTRACE_HASH_MAX_BITS; | |
1330 | ||
41fb61c2 | 1331 | ret = -ENOMEM; |
07fd5515 SR |
1332 | new_hash = alloc_ftrace_hash(bits); |
1333 | if (!new_hash) | |
41fb61c2 | 1334 | goto out; |
33dc9b12 SR |
1335 | |
1336 | size = 1 << src->size_bits; | |
1337 | for (i = 0; i < size; i++) { | |
1338 | hhd = &src->buckets[i]; | |
1339 | hlist_for_each_entry_safe(entry, tp, tn, hhd, hlist) { | |
1340 | if (bits > 0) | |
1341 | key = hash_long(entry->ip, bits); | |
1342 | else | |
1343 | key = 0; | |
1344 | remove_hash_entry(src, entry); | |
07fd5515 | 1345 | __add_hash_entry(new_hash, entry); |
33dc9b12 SR |
1346 | } |
1347 | } | |
1348 | ||
07fd5515 SR |
1349 | old_hash = *dst; |
1350 | rcu_assign_pointer(*dst, new_hash); | |
1351 | free_ftrace_hash_rcu(old_hash); | |
1352 | ||
41fb61c2 SR |
1353 | ret = 0; |
1354 | out: | |
1355 | /* | |
1356 | * Enable regardless of ret: | |
1357 | * On success, we enable the new hash. | |
1358 | * On failure, we re-enable the original hash. | |
1359 | */ | |
1360 | ftrace_hash_rec_enable(ops, enable); | |
1361 | ||
1362 | return ret; | |
33dc9b12 SR |
1363 | } |
1364 | ||
b848914c SR |
1365 | /* |
1366 | * Test the hashes for this ops to see if we want to call | |
1367 | * the ops->func or not. | |
1368 | * | |
1369 | * It's a match if the ip is in the ops->filter_hash or | |
1370 | * the filter_hash does not exist or is empty, | |
1371 | * AND | |
1372 | * the ip is not in the ops->notrace_hash. | |
cdbe61bf SR |
1373 | * |
1374 | * This needs to be called with preemption disabled as | |
1375 | * the hashes are freed with call_rcu_sched(). | |
b848914c SR |
1376 | */ |
1377 | static int | |
1378 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip) | |
1379 | { | |
1380 | struct ftrace_hash *filter_hash; | |
1381 | struct ftrace_hash *notrace_hash; | |
1382 | int ret; | |
1383 | ||
b848914c SR |
1384 | filter_hash = rcu_dereference_raw(ops->filter_hash); |
1385 | notrace_hash = rcu_dereference_raw(ops->notrace_hash); | |
1386 | ||
06a51d93 | 1387 | if ((ftrace_hash_empty(filter_hash) || |
b848914c | 1388 | ftrace_lookup_ip(filter_hash, ip)) && |
06a51d93 | 1389 | (ftrace_hash_empty(notrace_hash) || |
b848914c SR |
1390 | !ftrace_lookup_ip(notrace_hash, ip))) |
1391 | ret = 1; | |
1392 | else | |
1393 | ret = 0; | |
b848914c SR |
1394 | |
1395 | return ret; | |
1396 | } | |
1397 | ||
493762fc SR |
1398 | /* |
1399 | * This is a double for. Do not use 'break' to break out of the loop, | |
1400 | * you must use a goto. | |
1401 | */ | |
1402 | #define do_for_each_ftrace_rec(pg, rec) \ | |
1403 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
1404 | int _____i; \ | |
1405 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
1406 | rec = &pg->records[_____i]; | |
1407 | ||
1408 | #define while_for_each_ftrace_rec() \ | |
1409 | } \ | |
1410 | } | |
1411 | ||
5855fead SR |
1412 | |
1413 | static int ftrace_cmp_recs(const void *a, const void *b) | |
1414 | { | |
a650e02a SR |
1415 | const struct dyn_ftrace *key = a; |
1416 | const struct dyn_ftrace *rec = b; | |
5855fead | 1417 | |
a650e02a | 1418 | if (key->flags < rec->ip) |
5855fead | 1419 | return -1; |
a650e02a SR |
1420 | if (key->ip >= rec->ip + MCOUNT_INSN_SIZE) |
1421 | return 1; | |
5855fead SR |
1422 | return 0; |
1423 | } | |
1424 | ||
f0cf973a | 1425 | static unsigned long ftrace_location_range(unsigned long start, unsigned long end) |
c88fd863 SR |
1426 | { |
1427 | struct ftrace_page *pg; | |
1428 | struct dyn_ftrace *rec; | |
5855fead | 1429 | struct dyn_ftrace key; |
c88fd863 | 1430 | |
a650e02a SR |
1431 | key.ip = start; |
1432 | key.flags = end; /* overload flags, as it is unsigned long */ | |
5855fead SR |
1433 | |
1434 | for (pg = ftrace_pages_start; pg; pg = pg->next) { | |
a650e02a SR |
1435 | if (end < pg->records[0].ip || |
1436 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) | |
9644302e | 1437 | continue; |
5855fead SR |
1438 | rec = bsearch(&key, pg->records, pg->index, |
1439 | sizeof(struct dyn_ftrace), | |
1440 | ftrace_cmp_recs); | |
1441 | if (rec) | |
f0cf973a | 1442 | return rec->ip; |
5855fead | 1443 | } |
c88fd863 SR |
1444 | |
1445 | return 0; | |
1446 | } | |
1447 | ||
a650e02a SR |
1448 | /** |
1449 | * ftrace_location - return true if the ip giving is a traced location | |
1450 | * @ip: the instruction pointer to check | |
1451 | * | |
f0cf973a | 1452 | * Returns rec->ip if @ip given is a pointer to a ftrace location. |
a650e02a SR |
1453 | * That is, the instruction that is either a NOP or call to |
1454 | * the function tracer. It checks the ftrace internal tables to | |
1455 | * determine if the address belongs or not. | |
1456 | */ | |
f0cf973a | 1457 | unsigned long ftrace_location(unsigned long ip) |
a650e02a SR |
1458 | { |
1459 | return ftrace_location_range(ip, ip); | |
1460 | } | |
1461 | ||
1462 | /** | |
1463 | * ftrace_text_reserved - return true if range contains an ftrace location | |
1464 | * @start: start of range to search | |
1465 | * @end: end of range to search (inclusive). @end points to the last byte to check. | |
1466 | * | |
1467 | * Returns 1 if @start and @end contains a ftrace location. | |
1468 | * That is, the instruction that is either a NOP or call to | |
1469 | * the function tracer. It checks the ftrace internal tables to | |
1470 | * determine if the address belongs or not. | |
1471 | */ | |
1472 | int ftrace_text_reserved(void *start, void *end) | |
1473 | { | |
f0cf973a SR |
1474 | unsigned long ret; |
1475 | ||
1476 | ret = ftrace_location_range((unsigned long)start, | |
1477 | (unsigned long)end); | |
1478 | ||
1479 | return (int)!!ret; | |
a650e02a SR |
1480 | } |
1481 | ||
ed926f9b SR |
1482 | static void __ftrace_hash_rec_update(struct ftrace_ops *ops, |
1483 | int filter_hash, | |
1484 | bool inc) | |
1485 | { | |
1486 | struct ftrace_hash *hash; | |
1487 | struct ftrace_hash *other_hash; | |
1488 | struct ftrace_page *pg; | |
1489 | struct dyn_ftrace *rec; | |
1490 | int count = 0; | |
1491 | int all = 0; | |
1492 | ||
1493 | /* Only update if the ops has been registered */ | |
1494 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
1495 | return; | |
1496 | ||
1497 | /* | |
1498 | * In the filter_hash case: | |
1499 | * If the count is zero, we update all records. | |
1500 | * Otherwise we just update the items in the hash. | |
1501 | * | |
1502 | * In the notrace_hash case: | |
1503 | * We enable the update in the hash. | |
1504 | * As disabling notrace means enabling the tracing, | |
1505 | * and enabling notrace means disabling, the inc variable | |
1506 | * gets inversed. | |
1507 | */ | |
1508 | if (filter_hash) { | |
1509 | hash = ops->filter_hash; | |
1510 | other_hash = ops->notrace_hash; | |
06a51d93 | 1511 | if (ftrace_hash_empty(hash)) |
ed926f9b SR |
1512 | all = 1; |
1513 | } else { | |
1514 | inc = !inc; | |
1515 | hash = ops->notrace_hash; | |
1516 | other_hash = ops->filter_hash; | |
1517 | /* | |
1518 | * If the notrace hash has no items, | |
1519 | * then there's nothing to do. | |
1520 | */ | |
06a51d93 | 1521 | if (ftrace_hash_empty(hash)) |
ed926f9b SR |
1522 | return; |
1523 | } | |
1524 | ||
1525 | do_for_each_ftrace_rec(pg, rec) { | |
1526 | int in_other_hash = 0; | |
1527 | int in_hash = 0; | |
1528 | int match = 0; | |
1529 | ||
1530 | if (all) { | |
1531 | /* | |
1532 | * Only the filter_hash affects all records. | |
1533 | * Update if the record is not in the notrace hash. | |
1534 | */ | |
b848914c | 1535 | if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip)) |
ed926f9b SR |
1536 | match = 1; |
1537 | } else { | |
06a51d93 SR |
1538 | in_hash = !!ftrace_lookup_ip(hash, rec->ip); |
1539 | in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip); | |
ed926f9b SR |
1540 | |
1541 | /* | |
1542 | * | |
1543 | */ | |
1544 | if (filter_hash && in_hash && !in_other_hash) | |
1545 | match = 1; | |
1546 | else if (!filter_hash && in_hash && | |
06a51d93 | 1547 | (in_other_hash || ftrace_hash_empty(other_hash))) |
ed926f9b SR |
1548 | match = 1; |
1549 | } | |
1550 | if (!match) | |
1551 | continue; | |
1552 | ||
1553 | if (inc) { | |
1554 | rec->flags++; | |
1555 | if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == FTRACE_REF_MAX)) | |
1556 | return; | |
08f6fba5 SR |
1557 | /* |
1558 | * If any ops wants regs saved for this function | |
1559 | * then all ops will get saved regs. | |
1560 | */ | |
1561 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) | |
1562 | rec->flags |= FTRACE_FL_REGS; | |
ed926f9b SR |
1563 | } else { |
1564 | if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == 0)) | |
1565 | return; | |
1566 | rec->flags--; | |
1567 | } | |
1568 | count++; | |
1569 | /* Shortcut, if we handled all records, we are done. */ | |
1570 | if (!all && count == hash->count) | |
1571 | return; | |
1572 | } while_for_each_ftrace_rec(); | |
1573 | } | |
1574 | ||
1575 | static void ftrace_hash_rec_disable(struct ftrace_ops *ops, | |
1576 | int filter_hash) | |
1577 | { | |
1578 | __ftrace_hash_rec_update(ops, filter_hash, 0); | |
1579 | } | |
1580 | ||
1581 | static void ftrace_hash_rec_enable(struct ftrace_ops *ops, | |
1582 | int filter_hash) | |
1583 | { | |
1584 | __ftrace_hash_rec_update(ops, filter_hash, 1); | |
1585 | } | |
1586 | ||
b17e8a37 SR |
1587 | static void print_ip_ins(const char *fmt, unsigned char *p) |
1588 | { | |
1589 | int i; | |
1590 | ||
1591 | printk(KERN_CONT "%s", fmt); | |
1592 | ||
1593 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
1594 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
1595 | } | |
1596 | ||
c88fd863 SR |
1597 | /** |
1598 | * ftrace_bug - report and shutdown function tracer | |
1599 | * @failed: The failed type (EFAULT, EINVAL, EPERM) | |
1600 | * @ip: The address that failed | |
1601 | * | |
1602 | * The arch code that enables or disables the function tracing | |
1603 | * can call ftrace_bug() when it has detected a problem in | |
1604 | * modifying the code. @failed should be one of either: | |
1605 | * EFAULT - if the problem happens on reading the @ip address | |
1606 | * EINVAL - if what is read at @ip is not what was expected | |
1607 | * EPERM - if the problem happens on writting to the @ip address | |
1608 | */ | |
1609 | void ftrace_bug(int failed, unsigned long ip) | |
b17e8a37 SR |
1610 | { |
1611 | switch (failed) { | |
1612 | case -EFAULT: | |
1613 | FTRACE_WARN_ON_ONCE(1); | |
1614 | pr_info("ftrace faulted on modifying "); | |
1615 | print_ip_sym(ip); | |
1616 | break; | |
1617 | case -EINVAL: | |
1618 | FTRACE_WARN_ON_ONCE(1); | |
1619 | pr_info("ftrace failed to modify "); | |
1620 | print_ip_sym(ip); | |
b17e8a37 | 1621 | print_ip_ins(" actual: ", (unsigned char *)ip); |
b17e8a37 SR |
1622 | printk(KERN_CONT "\n"); |
1623 | break; | |
1624 | case -EPERM: | |
1625 | FTRACE_WARN_ON_ONCE(1); | |
1626 | pr_info("ftrace faulted on writing "); | |
1627 | print_ip_sym(ip); | |
1628 | break; | |
1629 | default: | |
1630 | FTRACE_WARN_ON_ONCE(1); | |
1631 | pr_info("ftrace faulted on unknown error "); | |
1632 | print_ip_sym(ip); | |
1633 | } | |
1634 | } | |
1635 | ||
c88fd863 | 1636 | static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update) |
5072c59f | 1637 | { |
64fbcd16 | 1638 | unsigned long flag = 0UL; |
e7d3737e | 1639 | |
982c350b | 1640 | /* |
30fb6aa7 | 1641 | * If we are updating calls: |
982c350b | 1642 | * |
ed926f9b SR |
1643 | * If the record has a ref count, then we need to enable it |
1644 | * because someone is using it. | |
982c350b | 1645 | * |
ed926f9b SR |
1646 | * Otherwise we make sure its disabled. |
1647 | * | |
30fb6aa7 | 1648 | * If we are disabling calls, then disable all records that |
ed926f9b | 1649 | * are enabled. |
982c350b | 1650 | */ |
c88fd863 | 1651 | if (enable && (rec->flags & ~FTRACE_FL_MASK)) |
ed926f9b | 1652 | flag = FTRACE_FL_ENABLED; |
982c350b | 1653 | |
08f6fba5 SR |
1654 | /* |
1655 | * If enabling and the REGS flag does not match the REGS_EN, then | |
1656 | * do not ignore this record. Set flags to fail the compare against | |
1657 | * ENABLED. | |
1658 | */ | |
1659 | if (flag && | |
1660 | (!(rec->flags & FTRACE_FL_REGS) != !(rec->flags & FTRACE_FL_REGS_EN))) | |
1661 | flag |= FTRACE_FL_REGS; | |
1662 | ||
64fbcd16 XG |
1663 | /* If the state of this record hasn't changed, then do nothing */ |
1664 | if ((rec->flags & FTRACE_FL_ENABLED) == flag) | |
c88fd863 | 1665 | return FTRACE_UPDATE_IGNORE; |
982c350b | 1666 | |
64fbcd16 | 1667 | if (flag) { |
08f6fba5 SR |
1668 | /* Save off if rec is being enabled (for return value) */ |
1669 | flag ^= rec->flags & FTRACE_FL_ENABLED; | |
1670 | ||
1671 | if (update) { | |
c88fd863 | 1672 | rec->flags |= FTRACE_FL_ENABLED; |
08f6fba5 SR |
1673 | if (flag & FTRACE_FL_REGS) { |
1674 | if (rec->flags & FTRACE_FL_REGS) | |
1675 | rec->flags |= FTRACE_FL_REGS_EN; | |
1676 | else | |
1677 | rec->flags &= ~FTRACE_FL_REGS_EN; | |
1678 | } | |
1679 | } | |
1680 | ||
1681 | /* | |
1682 | * If this record is being updated from a nop, then | |
1683 | * return UPDATE_MAKE_CALL. | |
1684 | * Otherwise, if the EN flag is set, then return | |
1685 | * UPDATE_MODIFY_CALL_REGS to tell the caller to convert | |
1686 | * from the non-save regs, to a save regs function. | |
1687 | * Otherwise, | |
1688 | * return UPDATE_MODIFY_CALL to tell the caller to convert | |
1689 | * from the save regs, to a non-save regs function. | |
1690 | */ | |
1691 | if (flag & FTRACE_FL_ENABLED) | |
1692 | return FTRACE_UPDATE_MAKE_CALL; | |
1693 | else if (rec->flags & FTRACE_FL_REGS_EN) | |
1694 | return FTRACE_UPDATE_MODIFY_CALL_REGS; | |
1695 | else | |
1696 | return FTRACE_UPDATE_MODIFY_CALL; | |
c88fd863 SR |
1697 | } |
1698 | ||
08f6fba5 SR |
1699 | if (update) { |
1700 | /* If there's no more users, clear all flags */ | |
1701 | if (!(rec->flags & ~FTRACE_FL_MASK)) | |
1702 | rec->flags = 0; | |
1703 | else | |
1704 | /* Just disable the record (keep REGS state) */ | |
1705 | rec->flags &= ~FTRACE_FL_ENABLED; | |
1706 | } | |
c88fd863 SR |
1707 | |
1708 | return FTRACE_UPDATE_MAKE_NOP; | |
1709 | } | |
1710 | ||
1711 | /** | |
1712 | * ftrace_update_record, set a record that now is tracing or not | |
1713 | * @rec: the record to update | |
1714 | * @enable: set to 1 if the record is tracing, zero to force disable | |
1715 | * | |
1716 | * The records that represent all functions that can be traced need | |
1717 | * to be updated when tracing has been enabled. | |
1718 | */ | |
1719 | int ftrace_update_record(struct dyn_ftrace *rec, int enable) | |
1720 | { | |
1721 | return ftrace_check_record(rec, enable, 1); | |
1722 | } | |
1723 | ||
1724 | /** | |
1725 | * ftrace_test_record, check if the record has been enabled or not | |
1726 | * @rec: the record to test | |
1727 | * @enable: set to 1 to check if enabled, 0 if it is disabled | |
1728 | * | |
1729 | * The arch code may need to test if a record is already set to | |
1730 | * tracing to determine how to modify the function code that it | |
1731 | * represents. | |
1732 | */ | |
1733 | int ftrace_test_record(struct dyn_ftrace *rec, int enable) | |
1734 | { | |
1735 | return ftrace_check_record(rec, enable, 0); | |
1736 | } | |
1737 | ||
1738 | static int | |
1739 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) | |
1740 | { | |
08f6fba5 | 1741 | unsigned long ftrace_old_addr; |
c88fd863 SR |
1742 | unsigned long ftrace_addr; |
1743 | int ret; | |
1744 | ||
c88fd863 SR |
1745 | ret = ftrace_update_record(rec, enable); |
1746 | ||
08f6fba5 SR |
1747 | if (rec->flags & FTRACE_FL_REGS) |
1748 | ftrace_addr = (unsigned long)FTRACE_REGS_ADDR; | |
1749 | else | |
1750 | ftrace_addr = (unsigned long)FTRACE_ADDR; | |
1751 | ||
c88fd863 SR |
1752 | switch (ret) { |
1753 | case FTRACE_UPDATE_IGNORE: | |
1754 | return 0; | |
1755 | ||
1756 | case FTRACE_UPDATE_MAKE_CALL: | |
64fbcd16 | 1757 | return ftrace_make_call(rec, ftrace_addr); |
c88fd863 SR |
1758 | |
1759 | case FTRACE_UPDATE_MAKE_NOP: | |
1760 | return ftrace_make_nop(NULL, rec, ftrace_addr); | |
08f6fba5 SR |
1761 | |
1762 | case FTRACE_UPDATE_MODIFY_CALL_REGS: | |
1763 | case FTRACE_UPDATE_MODIFY_CALL: | |
1764 | if (rec->flags & FTRACE_FL_REGS) | |
1765 | ftrace_old_addr = (unsigned long)FTRACE_ADDR; | |
1766 | else | |
1767 | ftrace_old_addr = (unsigned long)FTRACE_REGS_ADDR; | |
1768 | ||
1769 | return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr); | |
5072c59f SR |
1770 | } |
1771 | ||
c88fd863 | 1772 | return -1; /* unknow ftrace bug */ |
5072c59f SR |
1773 | } |
1774 | ||
e4f5d544 | 1775 | void __weak ftrace_replace_code(int enable) |
3c1720f0 | 1776 | { |
3c1720f0 SR |
1777 | struct dyn_ftrace *rec; |
1778 | struct ftrace_page *pg; | |
6a24a244 | 1779 | int failed; |
3c1720f0 | 1780 | |
45a4a237 SR |
1781 | if (unlikely(ftrace_disabled)) |
1782 | return; | |
1783 | ||
265c831c | 1784 | do_for_each_ftrace_rec(pg, rec) { |
e4f5d544 | 1785 | failed = __ftrace_replace_code(rec, enable); |
fa9d13cf | 1786 | if (failed) { |
3279ba37 SR |
1787 | ftrace_bug(failed, rec->ip); |
1788 | /* Stop processing */ | |
1789 | return; | |
3c1720f0 | 1790 | } |
265c831c | 1791 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
1792 | } |
1793 | ||
c88fd863 SR |
1794 | struct ftrace_rec_iter { |
1795 | struct ftrace_page *pg; | |
1796 | int index; | |
1797 | }; | |
1798 | ||
1799 | /** | |
1800 | * ftrace_rec_iter_start, start up iterating over traced functions | |
1801 | * | |
1802 | * Returns an iterator handle that is used to iterate over all | |
1803 | * the records that represent address locations where functions | |
1804 | * are traced. | |
1805 | * | |
1806 | * May return NULL if no records are available. | |
1807 | */ | |
1808 | struct ftrace_rec_iter *ftrace_rec_iter_start(void) | |
1809 | { | |
1810 | /* | |
1811 | * We only use a single iterator. | |
1812 | * Protected by the ftrace_lock mutex. | |
1813 | */ | |
1814 | static struct ftrace_rec_iter ftrace_rec_iter; | |
1815 | struct ftrace_rec_iter *iter = &ftrace_rec_iter; | |
1816 | ||
1817 | iter->pg = ftrace_pages_start; | |
1818 | iter->index = 0; | |
1819 | ||
1820 | /* Could have empty pages */ | |
1821 | while (iter->pg && !iter->pg->index) | |
1822 | iter->pg = iter->pg->next; | |
1823 | ||
1824 | if (!iter->pg) | |
1825 | return NULL; | |
1826 | ||
1827 | return iter; | |
1828 | } | |
1829 | ||
1830 | /** | |
1831 | * ftrace_rec_iter_next, get the next record to process. | |
1832 | * @iter: The handle to the iterator. | |
1833 | * | |
1834 | * Returns the next iterator after the given iterator @iter. | |
1835 | */ | |
1836 | struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter) | |
1837 | { | |
1838 | iter->index++; | |
1839 | ||
1840 | if (iter->index >= iter->pg->index) { | |
1841 | iter->pg = iter->pg->next; | |
1842 | iter->index = 0; | |
1843 | ||
1844 | /* Could have empty pages */ | |
1845 | while (iter->pg && !iter->pg->index) | |
1846 | iter->pg = iter->pg->next; | |
1847 | } | |
1848 | ||
1849 | if (!iter->pg) | |
1850 | return NULL; | |
1851 | ||
1852 | return iter; | |
1853 | } | |
1854 | ||
1855 | /** | |
1856 | * ftrace_rec_iter_record, get the record at the iterator location | |
1857 | * @iter: The current iterator location | |
1858 | * | |
1859 | * Returns the record that the current @iter is at. | |
1860 | */ | |
1861 | struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter) | |
1862 | { | |
1863 | return &iter->pg->records[iter->index]; | |
1864 | } | |
1865 | ||
492a7ea5 | 1866 | static int |
31e88909 | 1867 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 SR |
1868 | { |
1869 | unsigned long ip; | |
593eb8a2 | 1870 | int ret; |
3c1720f0 SR |
1871 | |
1872 | ip = rec->ip; | |
1873 | ||
45a4a237 SR |
1874 | if (unlikely(ftrace_disabled)) |
1875 | return 0; | |
1876 | ||
25aac9dc | 1877 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
593eb8a2 | 1878 | if (ret) { |
31e88909 | 1879 | ftrace_bug(ret, ip); |
492a7ea5 | 1880 | return 0; |
37ad5084 | 1881 | } |
492a7ea5 | 1882 | return 1; |
3c1720f0 SR |
1883 | } |
1884 | ||
000ab691 SR |
1885 | /* |
1886 | * archs can override this function if they must do something | |
1887 | * before the modifying code is performed. | |
1888 | */ | |
1889 | int __weak ftrace_arch_code_modify_prepare(void) | |
1890 | { | |
1891 | return 0; | |
1892 | } | |
1893 | ||
1894 | /* | |
1895 | * archs can override this function if they must do something | |
1896 | * after the modifying code is performed. | |
1897 | */ | |
1898 | int __weak ftrace_arch_code_modify_post_process(void) | |
1899 | { | |
1900 | return 0; | |
1901 | } | |
1902 | ||
8ed3e2cf | 1903 | void ftrace_modify_all_code(int command) |
3d083395 | 1904 | { |
8ed3e2cf | 1905 | if (command & FTRACE_UPDATE_CALLS) |
d61f82d0 | 1906 | ftrace_replace_code(1); |
8ed3e2cf | 1907 | else if (command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
1908 | ftrace_replace_code(0); |
1909 | ||
8ed3e2cf | 1910 | if (command & FTRACE_UPDATE_TRACE_FUNC) |
d61f82d0 SR |
1911 | ftrace_update_ftrace_func(ftrace_trace_function); |
1912 | ||
8ed3e2cf | 1913 | if (command & FTRACE_START_FUNC_RET) |
5a45cfe1 | 1914 | ftrace_enable_ftrace_graph_caller(); |
8ed3e2cf | 1915 | else if (command & FTRACE_STOP_FUNC_RET) |
5a45cfe1 | 1916 | ftrace_disable_ftrace_graph_caller(); |
8ed3e2cf SR |
1917 | } |
1918 | ||
1919 | static int __ftrace_modify_code(void *data) | |
1920 | { | |
1921 | int *command = data; | |
1922 | ||
1923 | ftrace_modify_all_code(*command); | |
5a45cfe1 | 1924 | |
d61f82d0 | 1925 | return 0; |
3d083395 SR |
1926 | } |
1927 | ||
c88fd863 SR |
1928 | /** |
1929 | * ftrace_run_stop_machine, go back to the stop machine method | |
1930 | * @command: The command to tell ftrace what to do | |
1931 | * | |
1932 | * If an arch needs to fall back to the stop machine method, the | |
1933 | * it can call this function. | |
1934 | */ | |
1935 | void ftrace_run_stop_machine(int command) | |
1936 | { | |
1937 | stop_machine(__ftrace_modify_code, &command, NULL); | |
1938 | } | |
1939 | ||
1940 | /** | |
1941 | * arch_ftrace_update_code, modify the code to trace or not trace | |
1942 | * @command: The command that needs to be done | |
1943 | * | |
1944 | * Archs can override this function if it does not need to | |
1945 | * run stop_machine() to modify code. | |
1946 | */ | |
1947 | void __weak arch_ftrace_update_code(int command) | |
1948 | { | |
1949 | ftrace_run_stop_machine(command); | |
1950 | } | |
1951 | ||
e309b41d | 1952 | static void ftrace_run_update_code(int command) |
3d083395 | 1953 | { |
000ab691 SR |
1954 | int ret; |
1955 | ||
1956 | ret = ftrace_arch_code_modify_prepare(); | |
1957 | FTRACE_WARN_ON(ret); | |
1958 | if (ret) | |
1959 | return; | |
c88fd863 SR |
1960 | /* |
1961 | * Do not call function tracer while we update the code. | |
1962 | * We are in stop machine. | |
1963 | */ | |
1964 | function_trace_stop++; | |
000ab691 | 1965 | |
c88fd863 SR |
1966 | /* |
1967 | * By default we use stop_machine() to modify the code. | |
1968 | * But archs can do what ever they want as long as it | |
1969 | * is safe. The stop_machine() is the safest, but also | |
1970 | * produces the most overhead. | |
1971 | */ | |
1972 | arch_ftrace_update_code(command); | |
1973 | ||
c88fd863 | 1974 | function_trace_stop--; |
000ab691 SR |
1975 | |
1976 | ret = ftrace_arch_code_modify_post_process(); | |
1977 | FTRACE_WARN_ON(ret); | |
3d083395 SR |
1978 | } |
1979 | ||
d61f82d0 | 1980 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 1981 | static int ftrace_start_up; |
b848914c | 1982 | static int global_start_up; |
df4fc315 SR |
1983 | |
1984 | static void ftrace_startup_enable(int command) | |
1985 | { | |
1986 | if (saved_ftrace_func != ftrace_trace_function) { | |
1987 | saved_ftrace_func = ftrace_trace_function; | |
1988 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
1989 | } | |
1990 | ||
1991 | if (!command || !ftrace_enabled) | |
1992 | return; | |
1993 | ||
1994 | ftrace_run_update_code(command); | |
1995 | } | |
d61f82d0 | 1996 | |
a1cd6173 | 1997 | static int ftrace_startup(struct ftrace_ops *ops, int command) |
3d083395 | 1998 | { |
b848914c SR |
1999 | bool hash_enable = true; |
2000 | ||
4eebcc81 | 2001 | if (unlikely(ftrace_disabled)) |
a1cd6173 | 2002 | return -ENODEV; |
4eebcc81 | 2003 | |
60a7ecf4 | 2004 | ftrace_start_up++; |
30fb6aa7 | 2005 | command |= FTRACE_UPDATE_CALLS; |
d61f82d0 | 2006 | |
b848914c SR |
2007 | /* ops marked global share the filter hashes */ |
2008 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { | |
2009 | ops = &global_ops; | |
2010 | /* Don't update hash if global is already set */ | |
2011 | if (global_start_up) | |
2012 | hash_enable = false; | |
2013 | global_start_up++; | |
2014 | } | |
2015 | ||
ed926f9b | 2016 | ops->flags |= FTRACE_OPS_FL_ENABLED; |
b848914c | 2017 | if (hash_enable) |
ed926f9b SR |
2018 | ftrace_hash_rec_enable(ops, 1); |
2019 | ||
df4fc315 | 2020 | ftrace_startup_enable(command); |
a1cd6173 SR |
2021 | |
2022 | return 0; | |
3d083395 SR |
2023 | } |
2024 | ||
bd69c30b | 2025 | static void ftrace_shutdown(struct ftrace_ops *ops, int command) |
3d083395 | 2026 | { |
b848914c SR |
2027 | bool hash_disable = true; |
2028 | ||
4eebcc81 SR |
2029 | if (unlikely(ftrace_disabled)) |
2030 | return; | |
2031 | ||
60a7ecf4 | 2032 | ftrace_start_up--; |
9ea1a153 FW |
2033 | /* |
2034 | * Just warn in case of unbalance, no need to kill ftrace, it's not | |
2035 | * critical but the ftrace_call callers may be never nopped again after | |
2036 | * further ftrace uses. | |
2037 | */ | |
2038 | WARN_ON_ONCE(ftrace_start_up < 0); | |
2039 | ||
b848914c SR |
2040 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
2041 | ops = &global_ops; | |
2042 | global_start_up--; | |
2043 | WARN_ON_ONCE(global_start_up < 0); | |
2044 | /* Don't update hash if global still has users */ | |
2045 | if (global_start_up) { | |
2046 | WARN_ON_ONCE(!ftrace_start_up); | |
2047 | hash_disable = false; | |
2048 | } | |
2049 | } | |
2050 | ||
2051 | if (hash_disable) | |
ed926f9b SR |
2052 | ftrace_hash_rec_disable(ops, 1); |
2053 | ||
b848914c | 2054 | if (ops != &global_ops || !global_start_up) |
ed926f9b | 2055 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; |
b848914c | 2056 | |
30fb6aa7 | 2057 | command |= FTRACE_UPDATE_CALLS; |
3d083395 | 2058 | |
d61f82d0 SR |
2059 | if (saved_ftrace_func != ftrace_trace_function) { |
2060 | saved_ftrace_func = ftrace_trace_function; | |
2061 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2062 | } | |
3d083395 | 2063 | |
d61f82d0 | 2064 | if (!command || !ftrace_enabled) |
e6ea44e9 | 2065 | return; |
d61f82d0 SR |
2066 | |
2067 | ftrace_run_update_code(command); | |
3d083395 SR |
2068 | } |
2069 | ||
e309b41d | 2070 | static void ftrace_startup_sysctl(void) |
b0fc494f | 2071 | { |
4eebcc81 SR |
2072 | if (unlikely(ftrace_disabled)) |
2073 | return; | |
2074 | ||
d61f82d0 SR |
2075 | /* Force update next time */ |
2076 | saved_ftrace_func = NULL; | |
60a7ecf4 SR |
2077 | /* ftrace_start_up is true if we want ftrace running */ |
2078 | if (ftrace_start_up) | |
30fb6aa7 | 2079 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); |
b0fc494f SR |
2080 | } |
2081 | ||
e309b41d | 2082 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 2083 | { |
4eebcc81 SR |
2084 | if (unlikely(ftrace_disabled)) |
2085 | return; | |
2086 | ||
60a7ecf4 SR |
2087 | /* ftrace_start_up is true if ftrace is running */ |
2088 | if (ftrace_start_up) | |
79e406d7 | 2089 | ftrace_run_update_code(FTRACE_DISABLE_CALLS); |
b0fc494f SR |
2090 | } |
2091 | ||
3d083395 SR |
2092 | static cycle_t ftrace_update_time; |
2093 | static unsigned long ftrace_update_cnt; | |
2094 | unsigned long ftrace_update_tot_cnt; | |
2095 | ||
f7bc8b61 SR |
2096 | static int ops_traces_mod(struct ftrace_ops *ops) |
2097 | { | |
2098 | struct ftrace_hash *hash; | |
2099 | ||
2100 | hash = ops->filter_hash; | |
06a51d93 | 2101 | return ftrace_hash_empty(hash); |
f7bc8b61 SR |
2102 | } |
2103 | ||
31e88909 | 2104 | static int ftrace_update_code(struct module *mod) |
3d083395 | 2105 | { |
85ae32ae | 2106 | struct ftrace_page *pg; |
e94142a6 | 2107 | struct dyn_ftrace *p; |
f22f9a89 | 2108 | cycle_t start, stop; |
f7bc8b61 | 2109 | unsigned long ref = 0; |
85ae32ae | 2110 | int i; |
f7bc8b61 SR |
2111 | |
2112 | /* | |
2113 | * When adding a module, we need to check if tracers are | |
2114 | * currently enabled and if they are set to trace all functions. | |
2115 | * If they are, we need to enable the module functions as well | |
2116 | * as update the reference counts for those function records. | |
2117 | */ | |
2118 | if (mod) { | |
2119 | struct ftrace_ops *ops; | |
2120 | ||
2121 | for (ops = ftrace_ops_list; | |
2122 | ops != &ftrace_list_end; ops = ops->next) { | |
2123 | if (ops->flags & FTRACE_OPS_FL_ENABLED && | |
2124 | ops_traces_mod(ops)) | |
2125 | ref++; | |
2126 | } | |
2127 | } | |
3d083395 | 2128 | |
750ed1a4 | 2129 | start = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
2130 | ftrace_update_cnt = 0; |
2131 | ||
85ae32ae | 2132 | for (pg = ftrace_new_pgs; pg; pg = pg->next) { |
3d083395 | 2133 | |
85ae32ae SR |
2134 | for (i = 0; i < pg->index; i++) { |
2135 | /* If something went wrong, bail without enabling anything */ | |
2136 | if (unlikely(ftrace_disabled)) | |
2137 | return -1; | |
f22f9a89 | 2138 | |
85ae32ae SR |
2139 | p = &pg->records[i]; |
2140 | p->flags = ref; | |
f22f9a89 | 2141 | |
85ae32ae SR |
2142 | /* |
2143 | * Do the initial record conversion from mcount jump | |
2144 | * to the NOP instructions. | |
2145 | */ | |
2146 | if (!ftrace_code_disable(mod, p)) | |
2147 | break; | |
5cb084bb | 2148 | |
85ae32ae | 2149 | ftrace_update_cnt++; |
5cb084bb | 2150 | |
85ae32ae SR |
2151 | /* |
2152 | * If the tracing is enabled, go ahead and enable the record. | |
2153 | * | |
2154 | * The reason not to enable the record immediatelly is the | |
2155 | * inherent check of ftrace_make_nop/ftrace_make_call for | |
2156 | * correct previous instructions. Making first the NOP | |
2157 | * conversion puts the module to the correct state, thus | |
2158 | * passing the ftrace_make_call check. | |
2159 | */ | |
2160 | if (ftrace_start_up && ref) { | |
2161 | int failed = __ftrace_replace_code(p, 1); | |
2162 | if (failed) | |
2163 | ftrace_bug(failed, p->ip); | |
2164 | } | |
5cb084bb | 2165 | } |
3d083395 SR |
2166 | } |
2167 | ||
85ae32ae SR |
2168 | ftrace_new_pgs = NULL; |
2169 | ||
750ed1a4 | 2170 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
2171 | ftrace_update_time = stop - start; |
2172 | ftrace_update_tot_cnt += ftrace_update_cnt; | |
2173 | ||
16444a8a ACM |
2174 | return 0; |
2175 | } | |
2176 | ||
a7900875 | 2177 | static int ftrace_allocate_records(struct ftrace_page *pg, int count) |
3c1720f0 | 2178 | { |
a7900875 | 2179 | int order; |
3c1720f0 | 2180 | int cnt; |
3c1720f0 | 2181 | |
a7900875 SR |
2182 | if (WARN_ON(!count)) |
2183 | return -EINVAL; | |
2184 | ||
2185 | order = get_count_order(DIV_ROUND_UP(count, ENTRIES_PER_PAGE)); | |
3c1720f0 SR |
2186 | |
2187 | /* | |
a7900875 SR |
2188 | * We want to fill as much as possible. No more than a page |
2189 | * may be empty. | |
3c1720f0 | 2190 | */ |
a7900875 SR |
2191 | while ((PAGE_SIZE << order) / ENTRY_SIZE >= count + ENTRIES_PER_PAGE) |
2192 | order--; | |
3c1720f0 | 2193 | |
a7900875 SR |
2194 | again: |
2195 | pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); | |
3c1720f0 | 2196 | |
a7900875 SR |
2197 | if (!pg->records) { |
2198 | /* if we can't allocate this size, try something smaller */ | |
2199 | if (!order) | |
2200 | return -ENOMEM; | |
2201 | order >>= 1; | |
2202 | goto again; | |
2203 | } | |
3c1720f0 | 2204 | |
a7900875 SR |
2205 | cnt = (PAGE_SIZE << order) / ENTRY_SIZE; |
2206 | pg->size = cnt; | |
3c1720f0 | 2207 | |
a7900875 SR |
2208 | if (cnt > count) |
2209 | cnt = count; | |
2210 | ||
2211 | return cnt; | |
2212 | } | |
2213 | ||
2214 | static struct ftrace_page * | |
2215 | ftrace_allocate_pages(unsigned long num_to_init) | |
2216 | { | |
2217 | struct ftrace_page *start_pg; | |
2218 | struct ftrace_page *pg; | |
2219 | int order; | |
2220 | int cnt; | |
2221 | ||
2222 | if (!num_to_init) | |
2223 | return 0; | |
2224 | ||
2225 | start_pg = pg = kzalloc(sizeof(*pg), GFP_KERNEL); | |
2226 | if (!pg) | |
2227 | return NULL; | |
2228 | ||
2229 | /* | |
2230 | * Try to allocate as much as possible in one continues | |
2231 | * location that fills in all of the space. We want to | |
2232 | * waste as little space as possible. | |
2233 | */ | |
2234 | for (;;) { | |
2235 | cnt = ftrace_allocate_records(pg, num_to_init); | |
2236 | if (cnt < 0) | |
2237 | goto free_pages; | |
2238 | ||
2239 | num_to_init -= cnt; | |
2240 | if (!num_to_init) | |
3c1720f0 SR |
2241 | break; |
2242 | ||
a7900875 SR |
2243 | pg->next = kzalloc(sizeof(*pg), GFP_KERNEL); |
2244 | if (!pg->next) | |
2245 | goto free_pages; | |
2246 | ||
3c1720f0 SR |
2247 | pg = pg->next; |
2248 | } | |
2249 | ||
a7900875 SR |
2250 | return start_pg; |
2251 | ||
2252 | free_pages: | |
2253 | while (start_pg) { | |
2254 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); | |
2255 | free_pages((unsigned long)pg->records, order); | |
2256 | start_pg = pg->next; | |
2257 | kfree(pg); | |
2258 | pg = start_pg; | |
2259 | } | |
2260 | pr_info("ftrace: FAILED to allocate memory for functions\n"); | |
2261 | return NULL; | |
2262 | } | |
2263 | ||
2264 | static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) | |
2265 | { | |
2266 | int cnt; | |
2267 | ||
2268 | if (!num_to_init) { | |
2269 | pr_info("ftrace: No functions to be traced?\n"); | |
2270 | return -1; | |
2271 | } | |
2272 | ||
2273 | cnt = num_to_init / ENTRIES_PER_PAGE; | |
2274 | pr_info("ftrace: allocating %ld entries in %d pages\n", | |
2275 | num_to_init, cnt + 1); | |
2276 | ||
3c1720f0 SR |
2277 | return 0; |
2278 | } | |
2279 | ||
5072c59f SR |
2280 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ |
2281 | ||
2282 | struct ftrace_iterator { | |
98c4fd04 | 2283 | loff_t pos; |
4aeb6967 SR |
2284 | loff_t func_pos; |
2285 | struct ftrace_page *pg; | |
2286 | struct dyn_ftrace *func; | |
2287 | struct ftrace_func_probe *probe; | |
2288 | struct trace_parser parser; | |
1cf41dd7 | 2289 | struct ftrace_hash *hash; |
33dc9b12 | 2290 | struct ftrace_ops *ops; |
4aeb6967 SR |
2291 | int hidx; |
2292 | int idx; | |
2293 | unsigned flags; | |
5072c59f SR |
2294 | }; |
2295 | ||
8fc0c701 | 2296 | static void * |
4aeb6967 | 2297 | t_hash_next(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
2298 | { |
2299 | struct ftrace_iterator *iter = m->private; | |
4aeb6967 | 2300 | struct hlist_node *hnd = NULL; |
8fc0c701 SR |
2301 | struct hlist_head *hhd; |
2302 | ||
8fc0c701 | 2303 | (*pos)++; |
98c4fd04 | 2304 | iter->pos = *pos; |
8fc0c701 | 2305 | |
4aeb6967 SR |
2306 | if (iter->probe) |
2307 | hnd = &iter->probe->node; | |
8fc0c701 SR |
2308 | retry: |
2309 | if (iter->hidx >= FTRACE_FUNC_HASHSIZE) | |
2310 | return NULL; | |
2311 | ||
2312 | hhd = &ftrace_func_hash[iter->hidx]; | |
2313 | ||
2314 | if (hlist_empty(hhd)) { | |
2315 | iter->hidx++; | |
2316 | hnd = NULL; | |
2317 | goto retry; | |
2318 | } | |
2319 | ||
2320 | if (!hnd) | |
2321 | hnd = hhd->first; | |
2322 | else { | |
2323 | hnd = hnd->next; | |
2324 | if (!hnd) { | |
2325 | iter->hidx++; | |
2326 | goto retry; | |
2327 | } | |
2328 | } | |
2329 | ||
4aeb6967 SR |
2330 | if (WARN_ON_ONCE(!hnd)) |
2331 | return NULL; | |
2332 | ||
2333 | iter->probe = hlist_entry(hnd, struct ftrace_func_probe, node); | |
2334 | ||
2335 | return iter; | |
8fc0c701 SR |
2336 | } |
2337 | ||
2338 | static void *t_hash_start(struct seq_file *m, loff_t *pos) | |
2339 | { | |
2340 | struct ftrace_iterator *iter = m->private; | |
2341 | void *p = NULL; | |
d82d6244 LZ |
2342 | loff_t l; |
2343 | ||
69a3083c SR |
2344 | if (!(iter->flags & FTRACE_ITER_DO_HASH)) |
2345 | return NULL; | |
2346 | ||
2bccfffd SR |
2347 | if (iter->func_pos > *pos) |
2348 | return NULL; | |
8fc0c701 | 2349 | |
d82d6244 | 2350 | iter->hidx = 0; |
2bccfffd | 2351 | for (l = 0; l <= (*pos - iter->func_pos); ) { |
4aeb6967 | 2352 | p = t_hash_next(m, &l); |
d82d6244 LZ |
2353 | if (!p) |
2354 | break; | |
2355 | } | |
4aeb6967 SR |
2356 | if (!p) |
2357 | return NULL; | |
2358 | ||
98c4fd04 SR |
2359 | /* Only set this if we have an item */ |
2360 | iter->flags |= FTRACE_ITER_HASH; | |
2361 | ||
4aeb6967 | 2362 | return iter; |
8fc0c701 SR |
2363 | } |
2364 | ||
4aeb6967 SR |
2365 | static int |
2366 | t_hash_show(struct seq_file *m, struct ftrace_iterator *iter) | |
8fc0c701 | 2367 | { |
b6887d79 | 2368 | struct ftrace_func_probe *rec; |
8fc0c701 | 2369 | |
4aeb6967 SR |
2370 | rec = iter->probe; |
2371 | if (WARN_ON_ONCE(!rec)) | |
2372 | return -EIO; | |
8fc0c701 | 2373 | |
809dcf29 SR |
2374 | if (rec->ops->print) |
2375 | return rec->ops->print(m, rec->ip, rec->ops, rec->data); | |
2376 | ||
b375a11a | 2377 | seq_printf(m, "%ps:%ps", (void *)rec->ip, (void *)rec->ops->func); |
8fc0c701 SR |
2378 | |
2379 | if (rec->data) | |
2380 | seq_printf(m, ":%p", rec->data); | |
2381 | seq_putc(m, '\n'); | |
2382 | ||
2383 | return 0; | |
2384 | } | |
2385 | ||
e309b41d | 2386 | static void * |
5072c59f SR |
2387 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2388 | { | |
2389 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 2390 | struct ftrace_ops *ops = iter->ops; |
5072c59f SR |
2391 | struct dyn_ftrace *rec = NULL; |
2392 | ||
45a4a237 SR |
2393 | if (unlikely(ftrace_disabled)) |
2394 | return NULL; | |
2395 | ||
8fc0c701 | 2396 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 2397 | return t_hash_next(m, pos); |
8fc0c701 | 2398 | |
5072c59f | 2399 | (*pos)++; |
1106b699 | 2400 | iter->pos = iter->func_pos = *pos; |
5072c59f | 2401 | |
0c75a3ed | 2402 | if (iter->flags & FTRACE_ITER_PRINTALL) |
57c072c7 | 2403 | return t_hash_start(m, pos); |
0c75a3ed | 2404 | |
5072c59f SR |
2405 | retry: |
2406 | if (iter->idx >= iter->pg->index) { | |
2407 | if (iter->pg->next) { | |
2408 | iter->pg = iter->pg->next; | |
2409 | iter->idx = 0; | |
2410 | goto retry; | |
2411 | } | |
2412 | } else { | |
2413 | rec = &iter->pg->records[iter->idx++]; | |
32082309 | 2414 | if (((iter->flags & FTRACE_ITER_FILTER) && |
f45948e8 | 2415 | !(ftrace_lookup_ip(ops->filter_hash, rec->ip))) || |
0183fb1c | 2416 | |
41c52c0d | 2417 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
647bcd03 SR |
2418 | !ftrace_lookup_ip(ops->notrace_hash, rec->ip)) || |
2419 | ||
2420 | ((iter->flags & FTRACE_ITER_ENABLED) && | |
2421 | !(rec->flags & ~FTRACE_FL_MASK))) { | |
2422 | ||
5072c59f SR |
2423 | rec = NULL; |
2424 | goto retry; | |
2425 | } | |
2426 | } | |
2427 | ||
4aeb6967 | 2428 | if (!rec) |
57c072c7 | 2429 | return t_hash_start(m, pos); |
4aeb6967 SR |
2430 | |
2431 | iter->func = rec; | |
2432 | ||
2433 | return iter; | |
5072c59f SR |
2434 | } |
2435 | ||
98c4fd04 SR |
2436 | static void reset_iter_read(struct ftrace_iterator *iter) |
2437 | { | |
2438 | iter->pos = 0; | |
2439 | iter->func_pos = 0; | |
2440 | iter->flags &= ~(FTRACE_ITER_PRINTALL & FTRACE_ITER_HASH); | |
5072c59f SR |
2441 | } |
2442 | ||
2443 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2444 | { | |
2445 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 2446 | struct ftrace_ops *ops = iter->ops; |
5072c59f | 2447 | void *p = NULL; |
694ce0a5 | 2448 | loff_t l; |
5072c59f | 2449 | |
8fc0c701 | 2450 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
2451 | |
2452 | if (unlikely(ftrace_disabled)) | |
2453 | return NULL; | |
2454 | ||
98c4fd04 SR |
2455 | /* |
2456 | * If an lseek was done, then reset and start from beginning. | |
2457 | */ | |
2458 | if (*pos < iter->pos) | |
2459 | reset_iter_read(iter); | |
2460 | ||
0c75a3ed SR |
2461 | /* |
2462 | * For set_ftrace_filter reading, if we have the filter | |
2463 | * off, we can short cut and just print out that all | |
2464 | * functions are enabled. | |
2465 | */ | |
06a51d93 SR |
2466 | if (iter->flags & FTRACE_ITER_FILTER && |
2467 | ftrace_hash_empty(ops->filter_hash)) { | |
0c75a3ed | 2468 | if (*pos > 0) |
8fc0c701 | 2469 | return t_hash_start(m, pos); |
0c75a3ed | 2470 | iter->flags |= FTRACE_ITER_PRINTALL; |
df091625 CW |
2471 | /* reset in case of seek/pread */ |
2472 | iter->flags &= ~FTRACE_ITER_HASH; | |
0c75a3ed SR |
2473 | return iter; |
2474 | } | |
2475 | ||
8fc0c701 SR |
2476 | if (iter->flags & FTRACE_ITER_HASH) |
2477 | return t_hash_start(m, pos); | |
2478 | ||
98c4fd04 SR |
2479 | /* |
2480 | * Unfortunately, we need to restart at ftrace_pages_start | |
2481 | * every time we let go of the ftrace_mutex. This is because | |
2482 | * those pointers can change without the lock. | |
2483 | */ | |
694ce0a5 LZ |
2484 | iter->pg = ftrace_pages_start; |
2485 | iter->idx = 0; | |
2486 | for (l = 0; l <= *pos; ) { | |
2487 | p = t_next(m, p, &l); | |
2488 | if (!p) | |
2489 | break; | |
50cdaf08 | 2490 | } |
5821e1b7 | 2491 | |
69a3083c SR |
2492 | if (!p) |
2493 | return t_hash_start(m, pos); | |
4aeb6967 SR |
2494 | |
2495 | return iter; | |
5072c59f SR |
2496 | } |
2497 | ||
2498 | static void t_stop(struct seq_file *m, void *p) | |
2499 | { | |
8fc0c701 | 2500 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
2501 | } |
2502 | ||
2503 | static int t_show(struct seq_file *m, void *v) | |
2504 | { | |
0c75a3ed | 2505 | struct ftrace_iterator *iter = m->private; |
4aeb6967 | 2506 | struct dyn_ftrace *rec; |
5072c59f | 2507 | |
8fc0c701 | 2508 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 2509 | return t_hash_show(m, iter); |
8fc0c701 | 2510 | |
0c75a3ed SR |
2511 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
2512 | seq_printf(m, "#### all functions enabled ####\n"); | |
2513 | return 0; | |
2514 | } | |
2515 | ||
4aeb6967 SR |
2516 | rec = iter->func; |
2517 | ||
5072c59f SR |
2518 | if (!rec) |
2519 | return 0; | |
2520 | ||
647bcd03 SR |
2521 | seq_printf(m, "%ps", (void *)rec->ip); |
2522 | if (iter->flags & FTRACE_ITER_ENABLED) | |
08f6fba5 SR |
2523 | seq_printf(m, " (%ld)%s", |
2524 | rec->flags & ~FTRACE_FL_MASK, | |
2525 | rec->flags & FTRACE_FL_REGS ? " R" : ""); | |
647bcd03 | 2526 | seq_printf(m, "\n"); |
5072c59f SR |
2527 | |
2528 | return 0; | |
2529 | } | |
2530 | ||
88e9d34c | 2531 | static const struct seq_operations show_ftrace_seq_ops = { |
5072c59f SR |
2532 | .start = t_start, |
2533 | .next = t_next, | |
2534 | .stop = t_stop, | |
2535 | .show = t_show, | |
2536 | }; | |
2537 | ||
e309b41d | 2538 | static int |
5072c59f SR |
2539 | ftrace_avail_open(struct inode *inode, struct file *file) |
2540 | { | |
2541 | struct ftrace_iterator *iter; | |
5072c59f | 2542 | |
4eebcc81 SR |
2543 | if (unlikely(ftrace_disabled)) |
2544 | return -ENODEV; | |
2545 | ||
50e18b94 JO |
2546 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
2547 | if (iter) { | |
2548 | iter->pg = ftrace_pages_start; | |
2549 | iter->ops = &global_ops; | |
4bf39a94 | 2550 | } |
5072c59f | 2551 | |
50e18b94 | 2552 | return iter ? 0 : -ENOMEM; |
5072c59f SR |
2553 | } |
2554 | ||
647bcd03 SR |
2555 | static int |
2556 | ftrace_enabled_open(struct inode *inode, struct file *file) | |
2557 | { | |
2558 | struct ftrace_iterator *iter; | |
647bcd03 SR |
2559 | |
2560 | if (unlikely(ftrace_disabled)) | |
2561 | return -ENODEV; | |
2562 | ||
50e18b94 JO |
2563 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
2564 | if (iter) { | |
2565 | iter->pg = ftrace_pages_start; | |
2566 | iter->flags = FTRACE_ITER_ENABLED; | |
2567 | iter->ops = &global_ops; | |
647bcd03 SR |
2568 | } |
2569 | ||
50e18b94 | 2570 | return iter ? 0 : -ENOMEM; |
647bcd03 SR |
2571 | } |
2572 | ||
1cf41dd7 | 2573 | static void ftrace_filter_reset(struct ftrace_hash *hash) |
5072c59f | 2574 | { |
52baf119 | 2575 | mutex_lock(&ftrace_lock); |
1cf41dd7 | 2576 | ftrace_hash_clear(hash); |
52baf119 | 2577 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
2578 | } |
2579 | ||
fc13cb0c SR |
2580 | /** |
2581 | * ftrace_regex_open - initialize function tracer filter files | |
2582 | * @ops: The ftrace_ops that hold the hash filters | |
2583 | * @flag: The type of filter to process | |
2584 | * @inode: The inode, usually passed in to your open routine | |
2585 | * @file: The file, usually passed in to your open routine | |
2586 | * | |
2587 | * ftrace_regex_open() initializes the filter files for the | |
2588 | * @ops. Depending on @flag it may process the filter hash or | |
2589 | * the notrace hash of @ops. With this called from the open | |
2590 | * routine, you can use ftrace_filter_write() for the write | |
2591 | * routine if @flag has FTRACE_ITER_FILTER set, or | |
2592 | * ftrace_notrace_write() if @flag has FTRACE_ITER_NOTRACE set. | |
2593 | * ftrace_regex_lseek() should be used as the lseek routine, and | |
2594 | * release must call ftrace_regex_release(). | |
2595 | */ | |
2596 | int | |
f45948e8 | 2597 | ftrace_regex_open(struct ftrace_ops *ops, int flag, |
1cf41dd7 | 2598 | struct inode *inode, struct file *file) |
5072c59f SR |
2599 | { |
2600 | struct ftrace_iterator *iter; | |
f45948e8 | 2601 | struct ftrace_hash *hash; |
5072c59f SR |
2602 | int ret = 0; |
2603 | ||
4eebcc81 SR |
2604 | if (unlikely(ftrace_disabled)) |
2605 | return -ENODEV; | |
2606 | ||
5072c59f SR |
2607 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
2608 | if (!iter) | |
2609 | return -ENOMEM; | |
2610 | ||
689fd8b6 | 2611 | if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) { |
2612 | kfree(iter); | |
2613 | return -ENOMEM; | |
2614 | } | |
2615 | ||
f45948e8 SR |
2616 | if (flag & FTRACE_ITER_NOTRACE) |
2617 | hash = ops->notrace_hash; | |
2618 | else | |
2619 | hash = ops->filter_hash; | |
2620 | ||
33dc9b12 SR |
2621 | iter->ops = ops; |
2622 | iter->flags = flag; | |
2623 | ||
2624 | if (file->f_mode & FMODE_WRITE) { | |
2625 | mutex_lock(&ftrace_lock); | |
2626 | iter->hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash); | |
2627 | mutex_unlock(&ftrace_lock); | |
2628 | ||
2629 | if (!iter->hash) { | |
2630 | trace_parser_put(&iter->parser); | |
2631 | kfree(iter); | |
2632 | return -ENOMEM; | |
2633 | } | |
2634 | } | |
1cf41dd7 | 2635 | |
41c52c0d | 2636 | mutex_lock(&ftrace_regex_lock); |
33dc9b12 | 2637 | |
5072c59f | 2638 | if ((file->f_mode & FMODE_WRITE) && |
8650ae32 | 2639 | (file->f_flags & O_TRUNC)) |
33dc9b12 | 2640 | ftrace_filter_reset(iter->hash); |
5072c59f SR |
2641 | |
2642 | if (file->f_mode & FMODE_READ) { | |
2643 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
2644 | |
2645 | ret = seq_open(file, &show_ftrace_seq_ops); | |
2646 | if (!ret) { | |
2647 | struct seq_file *m = file->private_data; | |
2648 | m->private = iter; | |
79fe249c | 2649 | } else { |
33dc9b12 SR |
2650 | /* Failed */ |
2651 | free_ftrace_hash(iter->hash); | |
79fe249c | 2652 | trace_parser_put(&iter->parser); |
5072c59f | 2653 | kfree(iter); |
79fe249c | 2654 | } |
5072c59f SR |
2655 | } else |
2656 | file->private_data = iter; | |
41c52c0d | 2657 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
2658 | |
2659 | return ret; | |
2660 | } | |
2661 | ||
41c52c0d SR |
2662 | static int |
2663 | ftrace_filter_open(struct inode *inode, struct file *file) | |
2664 | { | |
69a3083c SR |
2665 | return ftrace_regex_open(&global_ops, |
2666 | FTRACE_ITER_FILTER | FTRACE_ITER_DO_HASH, | |
2667 | inode, file); | |
41c52c0d SR |
2668 | } |
2669 | ||
2670 | static int | |
2671 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
2672 | { | |
f45948e8 | 2673 | return ftrace_regex_open(&global_ops, FTRACE_ITER_NOTRACE, |
1cf41dd7 | 2674 | inode, file); |
41c52c0d SR |
2675 | } |
2676 | ||
fc13cb0c | 2677 | loff_t |
41c52c0d | 2678 | ftrace_regex_lseek(struct file *file, loff_t offset, int origin) |
5072c59f SR |
2679 | { |
2680 | loff_t ret; | |
2681 | ||
2682 | if (file->f_mode & FMODE_READ) | |
2683 | ret = seq_lseek(file, offset, origin); | |
2684 | else | |
2685 | file->f_pos = ret = 1; | |
2686 | ||
2687 | return ret; | |
2688 | } | |
2689 | ||
64e7c440 | 2690 | static int ftrace_match(char *str, char *regex, int len, int type) |
9f4801e3 | 2691 | { |
9f4801e3 | 2692 | int matched = 0; |
751e9983 | 2693 | int slen; |
9f4801e3 | 2694 | |
9f4801e3 SR |
2695 | switch (type) { |
2696 | case MATCH_FULL: | |
2697 | if (strcmp(str, regex) == 0) | |
2698 | matched = 1; | |
2699 | break; | |
2700 | case MATCH_FRONT_ONLY: | |
2701 | if (strncmp(str, regex, len) == 0) | |
2702 | matched = 1; | |
2703 | break; | |
2704 | case MATCH_MIDDLE_ONLY: | |
2705 | if (strstr(str, regex)) | |
2706 | matched = 1; | |
2707 | break; | |
2708 | case MATCH_END_ONLY: | |
751e9983 LZ |
2709 | slen = strlen(str); |
2710 | if (slen >= len && memcmp(str + slen - len, regex, len) == 0) | |
9f4801e3 SR |
2711 | matched = 1; |
2712 | break; | |
2713 | } | |
2714 | ||
2715 | return matched; | |
2716 | } | |
2717 | ||
b448c4e3 | 2718 | static int |
1cf41dd7 | 2719 | enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int not) |
996e87be | 2720 | { |
b448c4e3 | 2721 | struct ftrace_func_entry *entry; |
b448c4e3 SR |
2722 | int ret = 0; |
2723 | ||
1cf41dd7 SR |
2724 | entry = ftrace_lookup_ip(hash, rec->ip); |
2725 | if (not) { | |
2726 | /* Do nothing if it doesn't exist */ | |
2727 | if (!entry) | |
2728 | return 0; | |
b448c4e3 | 2729 | |
33dc9b12 | 2730 | free_hash_entry(hash, entry); |
1cf41dd7 SR |
2731 | } else { |
2732 | /* Do nothing if it exists */ | |
2733 | if (entry) | |
2734 | return 0; | |
b448c4e3 | 2735 | |
1cf41dd7 | 2736 | ret = add_hash_entry(hash, rec->ip); |
b448c4e3 SR |
2737 | } |
2738 | return ret; | |
996e87be SR |
2739 | } |
2740 | ||
64e7c440 | 2741 | static int |
b9df92d2 SR |
2742 | ftrace_match_record(struct dyn_ftrace *rec, char *mod, |
2743 | char *regex, int len, int type) | |
64e7c440 SR |
2744 | { |
2745 | char str[KSYM_SYMBOL_LEN]; | |
b9df92d2 SR |
2746 | char *modname; |
2747 | ||
2748 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); | |
2749 | ||
2750 | if (mod) { | |
2751 | /* module lookup requires matching the module */ | |
2752 | if (!modname || strcmp(modname, mod)) | |
2753 | return 0; | |
2754 | ||
2755 | /* blank search means to match all funcs in the mod */ | |
2756 | if (!len) | |
2757 | return 1; | |
2758 | } | |
64e7c440 | 2759 | |
64e7c440 SR |
2760 | return ftrace_match(str, regex, len, type); |
2761 | } | |
2762 | ||
1cf41dd7 SR |
2763 | static int |
2764 | match_records(struct ftrace_hash *hash, char *buff, | |
2765 | int len, char *mod, int not) | |
9f4801e3 | 2766 | { |
b9df92d2 | 2767 | unsigned search_len = 0; |
9f4801e3 SR |
2768 | struct ftrace_page *pg; |
2769 | struct dyn_ftrace *rec; | |
b9df92d2 SR |
2770 | int type = MATCH_FULL; |
2771 | char *search = buff; | |
311d16da | 2772 | int found = 0; |
b448c4e3 | 2773 | int ret; |
9f4801e3 | 2774 | |
b9df92d2 SR |
2775 | if (len) { |
2776 | type = filter_parse_regex(buff, len, &search, ¬); | |
2777 | search_len = strlen(search); | |
2778 | } | |
9f4801e3 | 2779 | |
52baf119 | 2780 | mutex_lock(&ftrace_lock); |
265c831c | 2781 | |
b9df92d2 SR |
2782 | if (unlikely(ftrace_disabled)) |
2783 | goto out_unlock; | |
9f4801e3 | 2784 | |
265c831c | 2785 | do_for_each_ftrace_rec(pg, rec) { |
b9df92d2 | 2786 | if (ftrace_match_record(rec, mod, search, search_len, type)) { |
1cf41dd7 | 2787 | ret = enter_record(hash, rec, not); |
b448c4e3 SR |
2788 | if (ret < 0) { |
2789 | found = ret; | |
2790 | goto out_unlock; | |
2791 | } | |
311d16da | 2792 | found = 1; |
265c831c SR |
2793 | } |
2794 | } while_for_each_ftrace_rec(); | |
b9df92d2 | 2795 | out_unlock: |
52baf119 | 2796 | mutex_unlock(&ftrace_lock); |
311d16da LZ |
2797 | |
2798 | return found; | |
5072c59f SR |
2799 | } |
2800 | ||
64e7c440 | 2801 | static int |
1cf41dd7 | 2802 | ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) |
64e7c440 | 2803 | { |
1cf41dd7 | 2804 | return match_records(hash, buff, len, NULL, 0); |
64e7c440 SR |
2805 | } |
2806 | ||
1cf41dd7 SR |
2807 | static int |
2808 | ftrace_match_module_records(struct ftrace_hash *hash, char *buff, char *mod) | |
64e7c440 | 2809 | { |
64e7c440 | 2810 | int not = 0; |
6a24a244 | 2811 | |
64e7c440 SR |
2812 | /* blank or '*' mean the same */ |
2813 | if (strcmp(buff, "*") == 0) | |
2814 | buff[0] = 0; | |
2815 | ||
2816 | /* handle the case of 'dont filter this module' */ | |
2817 | if (strcmp(buff, "!") == 0 || strcmp(buff, "!*") == 0) { | |
2818 | buff[0] = 0; | |
2819 | not = 1; | |
2820 | } | |
2821 | ||
1cf41dd7 | 2822 | return match_records(hash, buff, strlen(buff), mod, not); |
64e7c440 SR |
2823 | } |
2824 | ||
f6180773 SR |
2825 | /* |
2826 | * We register the module command as a template to show others how | |
2827 | * to register the a command as well. | |
2828 | */ | |
2829 | ||
2830 | static int | |
43dd61c9 SR |
2831 | ftrace_mod_callback(struct ftrace_hash *hash, |
2832 | char *func, char *cmd, char *param, int enable) | |
f6180773 SR |
2833 | { |
2834 | char *mod; | |
b448c4e3 | 2835 | int ret = -EINVAL; |
f6180773 SR |
2836 | |
2837 | /* | |
2838 | * cmd == 'mod' because we only registered this func | |
2839 | * for the 'mod' ftrace_func_command. | |
2840 | * But if you register one func with multiple commands, | |
2841 | * you can tell which command was used by the cmd | |
2842 | * parameter. | |
2843 | */ | |
2844 | ||
2845 | /* we must have a module name */ | |
2846 | if (!param) | |
b448c4e3 | 2847 | return ret; |
f6180773 SR |
2848 | |
2849 | mod = strsep(¶m, ":"); | |
2850 | if (!strlen(mod)) | |
b448c4e3 | 2851 | return ret; |
f6180773 | 2852 | |
1cf41dd7 | 2853 | ret = ftrace_match_module_records(hash, func, mod); |
b448c4e3 SR |
2854 | if (!ret) |
2855 | ret = -EINVAL; | |
2856 | if (ret < 0) | |
2857 | return ret; | |
2858 | ||
2859 | return 0; | |
f6180773 SR |
2860 | } |
2861 | ||
2862 | static struct ftrace_func_command ftrace_mod_cmd = { | |
2863 | .name = "mod", | |
2864 | .func = ftrace_mod_callback, | |
2865 | }; | |
2866 | ||
2867 | static int __init ftrace_mod_cmd_init(void) | |
2868 | { | |
2869 | return register_ftrace_command(&ftrace_mod_cmd); | |
2870 | } | |
2871 | device_initcall(ftrace_mod_cmd_init); | |
2872 | ||
2f5f6ad9 | 2873 | static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 2874 | struct ftrace_ops *op, struct pt_regs *pt_regs) |
59df055f | 2875 | { |
b6887d79 | 2876 | struct ftrace_func_probe *entry; |
59df055f SR |
2877 | struct hlist_head *hhd; |
2878 | struct hlist_node *n; | |
2879 | unsigned long key; | |
59df055f SR |
2880 | |
2881 | key = hash_long(ip, FTRACE_HASH_BITS); | |
2882 | ||
2883 | hhd = &ftrace_func_hash[key]; | |
2884 | ||
2885 | if (hlist_empty(hhd)) | |
2886 | return; | |
2887 | ||
2888 | /* | |
2889 | * Disable preemption for these calls to prevent a RCU grace | |
2890 | * period. This syncs the hash iteration and freeing of items | |
2891 | * on the hash. rcu_read_lock is too dangerous here. | |
2892 | */ | |
5168ae50 | 2893 | preempt_disable_notrace(); |
59df055f SR |
2894 | hlist_for_each_entry_rcu(entry, n, hhd, node) { |
2895 | if (entry->ip == ip) | |
2896 | entry->ops->func(ip, parent_ip, &entry->data); | |
2897 | } | |
5168ae50 | 2898 | preempt_enable_notrace(); |
59df055f SR |
2899 | } |
2900 | ||
b6887d79 | 2901 | static struct ftrace_ops trace_probe_ops __read_mostly = |
59df055f | 2902 | { |
fb9fb015 | 2903 | .func = function_trace_probe_call, |
59df055f SR |
2904 | }; |
2905 | ||
b6887d79 | 2906 | static int ftrace_probe_registered; |
59df055f | 2907 | |
b6887d79 | 2908 | static void __enable_ftrace_function_probe(void) |
59df055f | 2909 | { |
b848914c | 2910 | int ret; |
59df055f SR |
2911 | int i; |
2912 | ||
b6887d79 | 2913 | if (ftrace_probe_registered) |
59df055f SR |
2914 | return; |
2915 | ||
2916 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
2917 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
2918 | if (hhd->first) | |
2919 | break; | |
2920 | } | |
2921 | /* Nothing registered? */ | |
2922 | if (i == FTRACE_FUNC_HASHSIZE) | |
2923 | return; | |
2924 | ||
b848914c SR |
2925 | ret = __register_ftrace_function(&trace_probe_ops); |
2926 | if (!ret) | |
a1cd6173 | 2927 | ret = ftrace_startup(&trace_probe_ops, 0); |
b848914c | 2928 | |
b6887d79 | 2929 | ftrace_probe_registered = 1; |
59df055f SR |
2930 | } |
2931 | ||
b6887d79 | 2932 | static void __disable_ftrace_function_probe(void) |
59df055f | 2933 | { |
b848914c | 2934 | int ret; |
59df055f SR |
2935 | int i; |
2936 | ||
b6887d79 | 2937 | if (!ftrace_probe_registered) |
59df055f SR |
2938 | return; |
2939 | ||
2940 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
2941 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
2942 | if (hhd->first) | |
2943 | return; | |
2944 | } | |
2945 | ||
2946 | /* no more funcs left */ | |
b848914c SR |
2947 | ret = __unregister_ftrace_function(&trace_probe_ops); |
2948 | if (!ret) | |
2949 | ftrace_shutdown(&trace_probe_ops, 0); | |
2950 | ||
b6887d79 | 2951 | ftrace_probe_registered = 0; |
59df055f SR |
2952 | } |
2953 | ||
2954 | ||
2955 | static void ftrace_free_entry_rcu(struct rcu_head *rhp) | |
2956 | { | |
b6887d79 SR |
2957 | struct ftrace_func_probe *entry = |
2958 | container_of(rhp, struct ftrace_func_probe, rcu); | |
59df055f SR |
2959 | |
2960 | if (entry->ops->free) | |
2961 | entry->ops->free(&entry->data); | |
2962 | kfree(entry); | |
2963 | } | |
2964 | ||
2965 | ||
2966 | int | |
b6887d79 | 2967 | register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
2968 | void *data) |
2969 | { | |
b6887d79 | 2970 | struct ftrace_func_probe *entry; |
59df055f SR |
2971 | struct ftrace_page *pg; |
2972 | struct dyn_ftrace *rec; | |
59df055f | 2973 | int type, len, not; |
6a24a244 | 2974 | unsigned long key; |
59df055f SR |
2975 | int count = 0; |
2976 | char *search; | |
2977 | ||
3f6fe06d | 2978 | type = filter_parse_regex(glob, strlen(glob), &search, ¬); |
59df055f SR |
2979 | len = strlen(search); |
2980 | ||
b6887d79 | 2981 | /* we do not support '!' for function probes */ |
59df055f SR |
2982 | if (WARN_ON(not)) |
2983 | return -EINVAL; | |
2984 | ||
2985 | mutex_lock(&ftrace_lock); | |
59df055f | 2986 | |
45a4a237 SR |
2987 | if (unlikely(ftrace_disabled)) |
2988 | goto out_unlock; | |
59df055f | 2989 | |
45a4a237 | 2990 | do_for_each_ftrace_rec(pg, rec) { |
59df055f | 2991 | |
b9df92d2 | 2992 | if (!ftrace_match_record(rec, NULL, search, len, type)) |
59df055f SR |
2993 | continue; |
2994 | ||
2995 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
2996 | if (!entry) { | |
b6887d79 | 2997 | /* If we did not process any, then return error */ |
59df055f SR |
2998 | if (!count) |
2999 | count = -ENOMEM; | |
3000 | goto out_unlock; | |
3001 | } | |
3002 | ||
3003 | count++; | |
3004 | ||
3005 | entry->data = data; | |
3006 | ||
3007 | /* | |
3008 | * The caller might want to do something special | |
3009 | * for each function we find. We call the callback | |
3010 | * to give the caller an opportunity to do so. | |
3011 | */ | |
3012 | if (ops->callback) { | |
3013 | if (ops->callback(rec->ip, &entry->data) < 0) { | |
3014 | /* caller does not like this func */ | |
3015 | kfree(entry); | |
3016 | continue; | |
3017 | } | |
3018 | } | |
3019 | ||
3020 | entry->ops = ops; | |
3021 | entry->ip = rec->ip; | |
3022 | ||
3023 | key = hash_long(entry->ip, FTRACE_HASH_BITS); | |
3024 | hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]); | |
3025 | ||
3026 | } while_for_each_ftrace_rec(); | |
b6887d79 | 3027 | __enable_ftrace_function_probe(); |
59df055f SR |
3028 | |
3029 | out_unlock: | |
3030 | mutex_unlock(&ftrace_lock); | |
3031 | ||
3032 | return count; | |
3033 | } | |
3034 | ||
3035 | enum { | |
b6887d79 SR |
3036 | PROBE_TEST_FUNC = 1, |
3037 | PROBE_TEST_DATA = 2 | |
59df055f SR |
3038 | }; |
3039 | ||
3040 | static void | |
b6887d79 | 3041 | __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3042 | void *data, int flags) |
3043 | { | |
b6887d79 | 3044 | struct ftrace_func_probe *entry; |
59df055f SR |
3045 | struct hlist_node *n, *tmp; |
3046 | char str[KSYM_SYMBOL_LEN]; | |
3047 | int type = MATCH_FULL; | |
3048 | int i, len = 0; | |
3049 | char *search; | |
3050 | ||
b36461da | 3051 | if (glob && (strcmp(glob, "*") == 0 || !strlen(glob))) |
59df055f | 3052 | glob = NULL; |
b36461da | 3053 | else if (glob) { |
59df055f SR |
3054 | int not; |
3055 | ||
3f6fe06d | 3056 | type = filter_parse_regex(glob, strlen(glob), &search, ¬); |
59df055f SR |
3057 | len = strlen(search); |
3058 | ||
b6887d79 | 3059 | /* we do not support '!' for function probes */ |
59df055f SR |
3060 | if (WARN_ON(not)) |
3061 | return; | |
3062 | } | |
3063 | ||
3064 | mutex_lock(&ftrace_lock); | |
3065 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
3066 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3067 | ||
3068 | hlist_for_each_entry_safe(entry, n, tmp, hhd, node) { | |
3069 | ||
3070 | /* break up if statements for readability */ | |
b6887d79 | 3071 | if ((flags & PROBE_TEST_FUNC) && entry->ops != ops) |
59df055f SR |
3072 | continue; |
3073 | ||
b6887d79 | 3074 | if ((flags & PROBE_TEST_DATA) && entry->data != data) |
59df055f SR |
3075 | continue; |
3076 | ||
3077 | /* do this last, since it is the most expensive */ | |
3078 | if (glob) { | |
3079 | kallsyms_lookup(entry->ip, NULL, NULL, | |
3080 | NULL, str); | |
3081 | if (!ftrace_match(str, glob, len, type)) | |
3082 | continue; | |
3083 | } | |
3084 | ||
3085 | hlist_del(&entry->node); | |
3086 | call_rcu(&entry->rcu, ftrace_free_entry_rcu); | |
3087 | } | |
3088 | } | |
b6887d79 | 3089 | __disable_ftrace_function_probe(); |
59df055f SR |
3090 | mutex_unlock(&ftrace_lock); |
3091 | } | |
3092 | ||
3093 | void | |
b6887d79 | 3094 | unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3095 | void *data) |
3096 | { | |
b6887d79 SR |
3097 | __unregister_ftrace_function_probe(glob, ops, data, |
3098 | PROBE_TEST_FUNC | PROBE_TEST_DATA); | |
59df055f SR |
3099 | } |
3100 | ||
3101 | void | |
b6887d79 | 3102 | unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops) |
59df055f | 3103 | { |
b6887d79 | 3104 | __unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC); |
59df055f SR |
3105 | } |
3106 | ||
b6887d79 | 3107 | void unregister_ftrace_function_probe_all(char *glob) |
59df055f | 3108 | { |
b6887d79 | 3109 | __unregister_ftrace_function_probe(glob, NULL, NULL, 0); |
59df055f SR |
3110 | } |
3111 | ||
f6180773 SR |
3112 | static LIST_HEAD(ftrace_commands); |
3113 | static DEFINE_MUTEX(ftrace_cmd_mutex); | |
3114 | ||
3115 | int register_ftrace_command(struct ftrace_func_command *cmd) | |
3116 | { | |
3117 | struct ftrace_func_command *p; | |
3118 | int ret = 0; | |
3119 | ||
3120 | mutex_lock(&ftrace_cmd_mutex); | |
3121 | list_for_each_entry(p, &ftrace_commands, list) { | |
3122 | if (strcmp(cmd->name, p->name) == 0) { | |
3123 | ret = -EBUSY; | |
3124 | goto out_unlock; | |
3125 | } | |
3126 | } | |
3127 | list_add(&cmd->list, &ftrace_commands); | |
3128 | out_unlock: | |
3129 | mutex_unlock(&ftrace_cmd_mutex); | |
3130 | ||
3131 | return ret; | |
3132 | } | |
3133 | ||
3134 | int unregister_ftrace_command(struct ftrace_func_command *cmd) | |
3135 | { | |
3136 | struct ftrace_func_command *p, *n; | |
3137 | int ret = -ENODEV; | |
3138 | ||
3139 | mutex_lock(&ftrace_cmd_mutex); | |
3140 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { | |
3141 | if (strcmp(cmd->name, p->name) == 0) { | |
3142 | ret = 0; | |
3143 | list_del_init(&p->list); | |
3144 | goto out_unlock; | |
3145 | } | |
3146 | } | |
3147 | out_unlock: | |
3148 | mutex_unlock(&ftrace_cmd_mutex); | |
3149 | ||
3150 | return ret; | |
3151 | } | |
3152 | ||
33dc9b12 SR |
3153 | static int ftrace_process_regex(struct ftrace_hash *hash, |
3154 | char *buff, int len, int enable) | |
64e7c440 | 3155 | { |
f6180773 | 3156 | char *func, *command, *next = buff; |
6a24a244 | 3157 | struct ftrace_func_command *p; |
0aff1c0c | 3158 | int ret = -EINVAL; |
64e7c440 SR |
3159 | |
3160 | func = strsep(&next, ":"); | |
3161 | ||
3162 | if (!next) { | |
1cf41dd7 | 3163 | ret = ftrace_match_records(hash, func, len); |
b448c4e3 SR |
3164 | if (!ret) |
3165 | ret = -EINVAL; | |
3166 | if (ret < 0) | |
3167 | return ret; | |
3168 | return 0; | |
64e7c440 SR |
3169 | } |
3170 | ||
f6180773 | 3171 | /* command found */ |
64e7c440 SR |
3172 | |
3173 | command = strsep(&next, ":"); | |
3174 | ||
f6180773 SR |
3175 | mutex_lock(&ftrace_cmd_mutex); |
3176 | list_for_each_entry(p, &ftrace_commands, list) { | |
3177 | if (strcmp(p->name, command) == 0) { | |
43dd61c9 | 3178 | ret = p->func(hash, func, command, next, enable); |
f6180773 SR |
3179 | goto out_unlock; |
3180 | } | |
64e7c440 | 3181 | } |
f6180773 SR |
3182 | out_unlock: |
3183 | mutex_unlock(&ftrace_cmd_mutex); | |
64e7c440 | 3184 | |
f6180773 | 3185 | return ret; |
64e7c440 SR |
3186 | } |
3187 | ||
e309b41d | 3188 | static ssize_t |
41c52c0d SR |
3189 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
3190 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
3191 | { |
3192 | struct ftrace_iterator *iter; | |
689fd8b6 | 3193 | struct trace_parser *parser; |
3194 | ssize_t ret, read; | |
5072c59f | 3195 | |
4ba7978e | 3196 | if (!cnt) |
5072c59f SR |
3197 | return 0; |
3198 | ||
41c52c0d | 3199 | mutex_lock(&ftrace_regex_lock); |
5072c59f | 3200 | |
45a4a237 SR |
3201 | ret = -ENODEV; |
3202 | if (unlikely(ftrace_disabled)) | |
3203 | goto out_unlock; | |
3204 | ||
5072c59f SR |
3205 | if (file->f_mode & FMODE_READ) { |
3206 | struct seq_file *m = file->private_data; | |
3207 | iter = m->private; | |
3208 | } else | |
3209 | iter = file->private_data; | |
3210 | ||
689fd8b6 | 3211 | parser = &iter->parser; |
3212 | read = trace_get_user(parser, ubuf, cnt, ppos); | |
5072c59f | 3213 | |
4ba7978e | 3214 | if (read >= 0 && trace_parser_loaded(parser) && |
689fd8b6 | 3215 | !trace_parser_cont(parser)) { |
33dc9b12 | 3216 | ret = ftrace_process_regex(iter->hash, parser->buffer, |
689fd8b6 | 3217 | parser->idx, enable); |
313254a9 | 3218 | trace_parser_clear(parser); |
5072c59f | 3219 | if (ret) |
ed146b25 | 3220 | goto out_unlock; |
eda1e328 | 3221 | } |
5072c59f | 3222 | |
5072c59f | 3223 | ret = read; |
ed146b25 | 3224 | out_unlock: |
689fd8b6 | 3225 | mutex_unlock(&ftrace_regex_lock); |
ed146b25 | 3226 | |
5072c59f SR |
3227 | return ret; |
3228 | } | |
3229 | ||
fc13cb0c | 3230 | ssize_t |
41c52c0d SR |
3231 | ftrace_filter_write(struct file *file, const char __user *ubuf, |
3232 | size_t cnt, loff_t *ppos) | |
3233 | { | |
3234 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
3235 | } | |
3236 | ||
fc13cb0c | 3237 | ssize_t |
41c52c0d SR |
3238 | ftrace_notrace_write(struct file *file, const char __user *ubuf, |
3239 | size_t cnt, loff_t *ppos) | |
3240 | { | |
3241 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
3242 | } | |
3243 | ||
33dc9b12 | 3244 | static int |
647664ea MH |
3245 | ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) |
3246 | { | |
3247 | struct ftrace_func_entry *entry; | |
3248 | ||
3249 | if (!ftrace_location(ip)) | |
3250 | return -EINVAL; | |
3251 | ||
3252 | if (remove) { | |
3253 | entry = ftrace_lookup_ip(hash, ip); | |
3254 | if (!entry) | |
3255 | return -ENOENT; | |
3256 | free_hash_entry(hash, entry); | |
3257 | return 0; | |
3258 | } | |
3259 | ||
3260 | return add_hash_entry(hash, ip); | |
3261 | } | |
3262 | ||
3263 | static int | |
3264 | ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, | |
3265 | unsigned long ip, int remove, int reset, int enable) | |
41c52c0d | 3266 | { |
33dc9b12 | 3267 | struct ftrace_hash **orig_hash; |
f45948e8 | 3268 | struct ftrace_hash *hash; |
33dc9b12 | 3269 | int ret; |
f45948e8 | 3270 | |
936e074b SR |
3271 | /* All global ops uses the global ops filters */ |
3272 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) | |
3273 | ops = &global_ops; | |
3274 | ||
41c52c0d | 3275 | if (unlikely(ftrace_disabled)) |
33dc9b12 | 3276 | return -ENODEV; |
41c52c0d | 3277 | |
f45948e8 | 3278 | if (enable) |
33dc9b12 | 3279 | orig_hash = &ops->filter_hash; |
f45948e8 | 3280 | else |
33dc9b12 SR |
3281 | orig_hash = &ops->notrace_hash; |
3282 | ||
3283 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
3284 | if (!hash) | |
3285 | return -ENOMEM; | |
f45948e8 | 3286 | |
41c52c0d SR |
3287 | mutex_lock(&ftrace_regex_lock); |
3288 | if (reset) | |
1cf41dd7 | 3289 | ftrace_filter_reset(hash); |
ac483c44 JO |
3290 | if (buf && !ftrace_match_records(hash, buf, len)) { |
3291 | ret = -EINVAL; | |
3292 | goto out_regex_unlock; | |
3293 | } | |
647664ea MH |
3294 | if (ip) { |
3295 | ret = ftrace_match_addr(hash, ip, remove); | |
3296 | if (ret < 0) | |
3297 | goto out_regex_unlock; | |
3298 | } | |
33dc9b12 SR |
3299 | |
3300 | mutex_lock(&ftrace_lock); | |
41fb61c2 | 3301 | ret = ftrace_hash_move(ops, enable, orig_hash, hash); |
072126f4 SR |
3302 | if (!ret && ops->flags & FTRACE_OPS_FL_ENABLED |
3303 | && ftrace_enabled) | |
30fb6aa7 | 3304 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); |
072126f4 | 3305 | |
33dc9b12 SR |
3306 | mutex_unlock(&ftrace_lock); |
3307 | ||
ac483c44 | 3308 | out_regex_unlock: |
41c52c0d | 3309 | mutex_unlock(&ftrace_regex_lock); |
33dc9b12 SR |
3310 | |
3311 | free_ftrace_hash(hash); | |
3312 | return ret; | |
41c52c0d SR |
3313 | } |
3314 | ||
647664ea MH |
3315 | static int |
3316 | ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove, | |
3317 | int reset, int enable) | |
3318 | { | |
3319 | return ftrace_set_hash(ops, 0, 0, ip, remove, reset, enable); | |
3320 | } | |
3321 | ||
3322 | /** | |
3323 | * ftrace_set_filter_ip - set a function to filter on in ftrace by address | |
3324 | * @ops - the ops to set the filter with | |
3325 | * @ip - the address to add to or remove from the filter. | |
3326 | * @remove - non zero to remove the ip from the filter | |
3327 | * @reset - non zero to reset all filters before applying this filter. | |
3328 | * | |
3329 | * Filters denote which functions should be enabled when tracing is enabled | |
3330 | * If @ip is NULL, it failes to update filter. | |
3331 | */ | |
3332 | int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, | |
3333 | int remove, int reset) | |
3334 | { | |
3335 | return ftrace_set_addr(ops, ip, remove, reset, 1); | |
3336 | } | |
3337 | EXPORT_SYMBOL_GPL(ftrace_set_filter_ip); | |
3338 | ||
3339 | static int | |
3340 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, | |
3341 | int reset, int enable) | |
3342 | { | |
3343 | return ftrace_set_hash(ops, buf, len, 0, 0, reset, enable); | |
3344 | } | |
3345 | ||
77a2b37d SR |
3346 | /** |
3347 | * ftrace_set_filter - set a function to filter on in ftrace | |
936e074b SR |
3348 | * @ops - the ops to set the filter with |
3349 | * @buf - the string that holds the function filter text. | |
3350 | * @len - the length of the string. | |
3351 | * @reset - non zero to reset all filters before applying this filter. | |
3352 | * | |
3353 | * Filters denote which functions should be enabled when tracing is enabled. | |
3354 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
3355 | */ | |
ac483c44 | 3356 | int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
3357 | int len, int reset) |
3358 | { | |
ac483c44 | 3359 | return ftrace_set_regex(ops, buf, len, reset, 1); |
936e074b SR |
3360 | } |
3361 | EXPORT_SYMBOL_GPL(ftrace_set_filter); | |
3362 | ||
3363 | /** | |
3364 | * ftrace_set_notrace - set a function to not trace in ftrace | |
3365 | * @ops - the ops to set the notrace filter with | |
3366 | * @buf - the string that holds the function notrace text. | |
3367 | * @len - the length of the string. | |
3368 | * @reset - non zero to reset all filters before applying this filter. | |
3369 | * | |
3370 | * Notrace Filters denote which functions should not be enabled when tracing | |
3371 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
3372 | * for tracing. | |
3373 | */ | |
ac483c44 | 3374 | int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
3375 | int len, int reset) |
3376 | { | |
ac483c44 | 3377 | return ftrace_set_regex(ops, buf, len, reset, 0); |
936e074b SR |
3378 | } |
3379 | EXPORT_SYMBOL_GPL(ftrace_set_notrace); | |
3380 | /** | |
3381 | * ftrace_set_filter - set a function to filter on in ftrace | |
3382 | * @ops - the ops to set the filter with | |
77a2b37d SR |
3383 | * @buf - the string that holds the function filter text. |
3384 | * @len - the length of the string. | |
3385 | * @reset - non zero to reset all filters before applying this filter. | |
3386 | * | |
3387 | * Filters denote which functions should be enabled when tracing is enabled. | |
3388 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
3389 | */ | |
936e074b | 3390 | void ftrace_set_global_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 3391 | { |
f45948e8 | 3392 | ftrace_set_regex(&global_ops, buf, len, reset, 1); |
41c52c0d | 3393 | } |
936e074b | 3394 | EXPORT_SYMBOL_GPL(ftrace_set_global_filter); |
4eebcc81 | 3395 | |
41c52c0d SR |
3396 | /** |
3397 | * ftrace_set_notrace - set a function to not trace in ftrace | |
936e074b | 3398 | * @ops - the ops to set the notrace filter with |
41c52c0d SR |
3399 | * @buf - the string that holds the function notrace text. |
3400 | * @len - the length of the string. | |
3401 | * @reset - non zero to reset all filters before applying this filter. | |
3402 | * | |
3403 | * Notrace Filters denote which functions should not be enabled when tracing | |
3404 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
3405 | * for tracing. | |
3406 | */ | |
936e074b | 3407 | void ftrace_set_global_notrace(unsigned char *buf, int len, int reset) |
41c52c0d | 3408 | { |
f45948e8 | 3409 | ftrace_set_regex(&global_ops, buf, len, reset, 0); |
77a2b37d | 3410 | } |
936e074b | 3411 | EXPORT_SYMBOL_GPL(ftrace_set_global_notrace); |
77a2b37d | 3412 | |
2af15d6a SR |
3413 | /* |
3414 | * command line interface to allow users to set filters on boot up. | |
3415 | */ | |
3416 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE | |
3417 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; | |
3418 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; | |
3419 | ||
3420 | static int __init set_ftrace_notrace(char *str) | |
3421 | { | |
3422 | strncpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); | |
3423 | return 1; | |
3424 | } | |
3425 | __setup("ftrace_notrace=", set_ftrace_notrace); | |
3426 | ||
3427 | static int __init set_ftrace_filter(char *str) | |
3428 | { | |
3429 | strncpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); | |
3430 | return 1; | |
3431 | } | |
3432 | __setup("ftrace_filter=", set_ftrace_filter); | |
3433 | ||
369bc18f | 3434 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
f6060f46 | 3435 | static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; |
801c29fd SR |
3436 | static int ftrace_set_func(unsigned long *array, int *idx, char *buffer); |
3437 | ||
369bc18f SA |
3438 | static int __init set_graph_function(char *str) |
3439 | { | |
06f43d66 | 3440 | strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); |
369bc18f SA |
3441 | return 1; |
3442 | } | |
3443 | __setup("ftrace_graph_filter=", set_graph_function); | |
3444 | ||
3445 | static void __init set_ftrace_early_graph(char *buf) | |
3446 | { | |
3447 | int ret; | |
3448 | char *func; | |
3449 | ||
3450 | while (buf) { | |
3451 | func = strsep(&buf, ","); | |
3452 | /* we allow only one expression at a time */ | |
3453 | ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, | |
3454 | func); | |
3455 | if (ret) | |
3456 | printk(KERN_DEBUG "ftrace: function %s not " | |
3457 | "traceable\n", func); | |
3458 | } | |
3459 | } | |
3460 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
3461 | ||
2a85a37f SR |
3462 | void __init |
3463 | ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable) | |
2af15d6a SR |
3464 | { |
3465 | char *func; | |
3466 | ||
3467 | while (buf) { | |
3468 | func = strsep(&buf, ","); | |
f45948e8 | 3469 | ftrace_set_regex(ops, func, strlen(func), 0, enable); |
2af15d6a SR |
3470 | } |
3471 | } | |
3472 | ||
3473 | static void __init set_ftrace_early_filters(void) | |
3474 | { | |
3475 | if (ftrace_filter_buf[0]) | |
2a85a37f | 3476 | ftrace_set_early_filter(&global_ops, ftrace_filter_buf, 1); |
2af15d6a | 3477 | if (ftrace_notrace_buf[0]) |
2a85a37f | 3478 | ftrace_set_early_filter(&global_ops, ftrace_notrace_buf, 0); |
369bc18f SA |
3479 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
3480 | if (ftrace_graph_buf[0]) | |
3481 | set_ftrace_early_graph(ftrace_graph_buf); | |
3482 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
2af15d6a SR |
3483 | } |
3484 | ||
fc13cb0c | 3485 | int ftrace_regex_release(struct inode *inode, struct file *file) |
5072c59f SR |
3486 | { |
3487 | struct seq_file *m = (struct seq_file *)file->private_data; | |
3488 | struct ftrace_iterator *iter; | |
33dc9b12 | 3489 | struct ftrace_hash **orig_hash; |
689fd8b6 | 3490 | struct trace_parser *parser; |
ed926f9b | 3491 | int filter_hash; |
33dc9b12 | 3492 | int ret; |
5072c59f | 3493 | |
41c52c0d | 3494 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
3495 | if (file->f_mode & FMODE_READ) { |
3496 | iter = m->private; | |
3497 | ||
3498 | seq_release(inode, file); | |
3499 | } else | |
3500 | iter = file->private_data; | |
3501 | ||
689fd8b6 | 3502 | parser = &iter->parser; |
3503 | if (trace_parser_loaded(parser)) { | |
3504 | parser->buffer[parser->idx] = 0; | |
1cf41dd7 | 3505 | ftrace_match_records(iter->hash, parser->buffer, parser->idx); |
5072c59f SR |
3506 | } |
3507 | ||
689fd8b6 | 3508 | trace_parser_put(parser); |
689fd8b6 | 3509 | |
058e297d | 3510 | if (file->f_mode & FMODE_WRITE) { |
ed926f9b SR |
3511 | filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); |
3512 | ||
3513 | if (filter_hash) | |
33dc9b12 | 3514 | orig_hash = &iter->ops->filter_hash; |
ed926f9b SR |
3515 | else |
3516 | orig_hash = &iter->ops->notrace_hash; | |
33dc9b12 | 3517 | |
058e297d | 3518 | mutex_lock(&ftrace_lock); |
41fb61c2 SR |
3519 | ret = ftrace_hash_move(iter->ops, filter_hash, |
3520 | orig_hash, iter->hash); | |
3521 | if (!ret && (iter->ops->flags & FTRACE_OPS_FL_ENABLED) | |
3522 | && ftrace_enabled) | |
30fb6aa7 | 3523 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); |
41fb61c2 | 3524 | |
058e297d SR |
3525 | mutex_unlock(&ftrace_lock); |
3526 | } | |
33dc9b12 SR |
3527 | free_ftrace_hash(iter->hash); |
3528 | kfree(iter); | |
058e297d | 3529 | |
41c52c0d | 3530 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
3531 | return 0; |
3532 | } | |
3533 | ||
5e2336a0 | 3534 | static const struct file_operations ftrace_avail_fops = { |
5072c59f SR |
3535 | .open = ftrace_avail_open, |
3536 | .read = seq_read, | |
3537 | .llseek = seq_lseek, | |
3be04b47 | 3538 | .release = seq_release_private, |
5072c59f SR |
3539 | }; |
3540 | ||
647bcd03 SR |
3541 | static const struct file_operations ftrace_enabled_fops = { |
3542 | .open = ftrace_enabled_open, | |
3543 | .read = seq_read, | |
3544 | .llseek = seq_lseek, | |
3545 | .release = seq_release_private, | |
3546 | }; | |
3547 | ||
5e2336a0 | 3548 | static const struct file_operations ftrace_filter_fops = { |
5072c59f | 3549 | .open = ftrace_filter_open, |
850a80cf | 3550 | .read = seq_read, |
5072c59f | 3551 | .write = ftrace_filter_write, |
98c4fd04 | 3552 | .llseek = ftrace_regex_lseek, |
1cf41dd7 | 3553 | .release = ftrace_regex_release, |
5072c59f SR |
3554 | }; |
3555 | ||
5e2336a0 | 3556 | static const struct file_operations ftrace_notrace_fops = { |
41c52c0d | 3557 | .open = ftrace_notrace_open, |
850a80cf | 3558 | .read = seq_read, |
41c52c0d SR |
3559 | .write = ftrace_notrace_write, |
3560 | .llseek = ftrace_regex_lseek, | |
1cf41dd7 | 3561 | .release = ftrace_regex_release, |
41c52c0d SR |
3562 | }; |
3563 | ||
ea4e2bc4 SR |
3564 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
3565 | ||
3566 | static DEFINE_MUTEX(graph_lock); | |
3567 | ||
3568 | int ftrace_graph_count; | |
c7c6b1fe | 3569 | int ftrace_graph_filter_enabled; |
ea4e2bc4 SR |
3570 | unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; |
3571 | ||
3572 | static void * | |
85951842 | 3573 | __g_next(struct seq_file *m, loff_t *pos) |
ea4e2bc4 | 3574 | { |
85951842 | 3575 | if (*pos >= ftrace_graph_count) |
ea4e2bc4 | 3576 | return NULL; |
a4ec5e0c | 3577 | return &ftrace_graph_funcs[*pos]; |
85951842 | 3578 | } |
ea4e2bc4 | 3579 | |
85951842 LZ |
3580 | static void * |
3581 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
3582 | { | |
3583 | (*pos)++; | |
3584 | return __g_next(m, pos); | |
ea4e2bc4 SR |
3585 | } |
3586 | ||
3587 | static void *g_start(struct seq_file *m, loff_t *pos) | |
3588 | { | |
ea4e2bc4 SR |
3589 | mutex_lock(&graph_lock); |
3590 | ||
f9349a8f | 3591 | /* Nothing, tell g_show to print all functions are enabled */ |
c7c6b1fe | 3592 | if (!ftrace_graph_filter_enabled && !*pos) |
f9349a8f FW |
3593 | return (void *)1; |
3594 | ||
85951842 | 3595 | return __g_next(m, pos); |
ea4e2bc4 SR |
3596 | } |
3597 | ||
3598 | static void g_stop(struct seq_file *m, void *p) | |
3599 | { | |
3600 | mutex_unlock(&graph_lock); | |
3601 | } | |
3602 | ||
3603 | static int g_show(struct seq_file *m, void *v) | |
3604 | { | |
3605 | unsigned long *ptr = v; | |
ea4e2bc4 SR |
3606 | |
3607 | if (!ptr) | |
3608 | return 0; | |
3609 | ||
f9349a8f FW |
3610 | if (ptr == (unsigned long *)1) { |
3611 | seq_printf(m, "#### all functions enabled ####\n"); | |
3612 | return 0; | |
3613 | } | |
3614 | ||
b375a11a | 3615 | seq_printf(m, "%ps\n", (void *)*ptr); |
ea4e2bc4 SR |
3616 | |
3617 | return 0; | |
3618 | } | |
3619 | ||
88e9d34c | 3620 | static const struct seq_operations ftrace_graph_seq_ops = { |
ea4e2bc4 SR |
3621 | .start = g_start, |
3622 | .next = g_next, | |
3623 | .stop = g_stop, | |
3624 | .show = g_show, | |
3625 | }; | |
3626 | ||
3627 | static int | |
3628 | ftrace_graph_open(struct inode *inode, struct file *file) | |
3629 | { | |
3630 | int ret = 0; | |
3631 | ||
3632 | if (unlikely(ftrace_disabled)) | |
3633 | return -ENODEV; | |
3634 | ||
3635 | mutex_lock(&graph_lock); | |
3636 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 3637 | (file->f_flags & O_TRUNC)) { |
c7c6b1fe | 3638 | ftrace_graph_filter_enabled = 0; |
ea4e2bc4 SR |
3639 | ftrace_graph_count = 0; |
3640 | memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); | |
3641 | } | |
a4ec5e0c | 3642 | mutex_unlock(&graph_lock); |
ea4e2bc4 | 3643 | |
a4ec5e0c | 3644 | if (file->f_mode & FMODE_READ) |
ea4e2bc4 | 3645 | ret = seq_open(file, &ftrace_graph_seq_ops); |
ea4e2bc4 SR |
3646 | |
3647 | return ret; | |
3648 | } | |
3649 | ||
87827111 LZ |
3650 | static int |
3651 | ftrace_graph_release(struct inode *inode, struct file *file) | |
3652 | { | |
3653 | if (file->f_mode & FMODE_READ) | |
3654 | seq_release(inode, file); | |
3655 | return 0; | |
3656 | } | |
3657 | ||
ea4e2bc4 | 3658 | static int |
f9349a8f | 3659 | ftrace_set_func(unsigned long *array, int *idx, char *buffer) |
ea4e2bc4 | 3660 | { |
ea4e2bc4 SR |
3661 | struct dyn_ftrace *rec; |
3662 | struct ftrace_page *pg; | |
f9349a8f | 3663 | int search_len; |
c7c6b1fe | 3664 | int fail = 1; |
f9349a8f FW |
3665 | int type, not; |
3666 | char *search; | |
3667 | bool exists; | |
3668 | int i; | |
ea4e2bc4 | 3669 | |
f9349a8f | 3670 | /* decode regex */ |
3f6fe06d | 3671 | type = filter_parse_regex(buffer, strlen(buffer), &search, ¬); |
c7c6b1fe LZ |
3672 | if (!not && *idx >= FTRACE_GRAPH_MAX_FUNCS) |
3673 | return -EBUSY; | |
f9349a8f FW |
3674 | |
3675 | search_len = strlen(search); | |
3676 | ||
52baf119 | 3677 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
3678 | |
3679 | if (unlikely(ftrace_disabled)) { | |
3680 | mutex_unlock(&ftrace_lock); | |
3681 | return -ENODEV; | |
3682 | } | |
3683 | ||
265c831c SR |
3684 | do_for_each_ftrace_rec(pg, rec) { |
3685 | ||
b9df92d2 | 3686 | if (ftrace_match_record(rec, NULL, search, search_len, type)) { |
c7c6b1fe | 3687 | /* if it is in the array */ |
f9349a8f | 3688 | exists = false; |
c7c6b1fe | 3689 | for (i = 0; i < *idx; i++) { |
f9349a8f FW |
3690 | if (array[i] == rec->ip) { |
3691 | exists = true; | |
265c831c SR |
3692 | break; |
3693 | } | |
c7c6b1fe LZ |
3694 | } |
3695 | ||
3696 | if (!not) { | |
3697 | fail = 0; | |
3698 | if (!exists) { | |
3699 | array[(*idx)++] = rec->ip; | |
3700 | if (*idx >= FTRACE_GRAPH_MAX_FUNCS) | |
3701 | goto out; | |
3702 | } | |
3703 | } else { | |
3704 | if (exists) { | |
3705 | array[i] = array[--(*idx)]; | |
3706 | array[*idx] = 0; | |
3707 | fail = 0; | |
3708 | } | |
3709 | } | |
ea4e2bc4 | 3710 | } |
265c831c | 3711 | } while_for_each_ftrace_rec(); |
c7c6b1fe | 3712 | out: |
52baf119 | 3713 | mutex_unlock(&ftrace_lock); |
ea4e2bc4 | 3714 | |
c7c6b1fe LZ |
3715 | if (fail) |
3716 | return -EINVAL; | |
3717 | ||
3718 | ftrace_graph_filter_enabled = 1; | |
3719 | return 0; | |
ea4e2bc4 SR |
3720 | } |
3721 | ||
3722 | static ssize_t | |
3723 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
3724 | size_t cnt, loff_t *ppos) | |
3725 | { | |
689fd8b6 | 3726 | struct trace_parser parser; |
4ba7978e | 3727 | ssize_t read, ret; |
ea4e2bc4 | 3728 | |
c7c6b1fe | 3729 | if (!cnt) |
ea4e2bc4 SR |
3730 | return 0; |
3731 | ||
3732 | mutex_lock(&graph_lock); | |
3733 | ||
689fd8b6 | 3734 | if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) { |
3735 | ret = -ENOMEM; | |
1eb90f13 | 3736 | goto out_unlock; |
ea4e2bc4 SR |
3737 | } |
3738 | ||
689fd8b6 | 3739 | read = trace_get_user(&parser, ubuf, cnt, ppos); |
ea4e2bc4 | 3740 | |
4ba7978e | 3741 | if (read >= 0 && trace_parser_loaded((&parser))) { |
689fd8b6 | 3742 | parser.buffer[parser.idx] = 0; |
3743 | ||
3744 | /* we allow only one expression at a time */ | |
a4ec5e0c | 3745 | ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, |
689fd8b6 | 3746 | parser.buffer); |
ea4e2bc4 | 3747 | if (ret) |
1eb90f13 | 3748 | goto out_free; |
ea4e2bc4 | 3749 | } |
ea4e2bc4 SR |
3750 | |
3751 | ret = read; | |
1eb90f13 LZ |
3752 | |
3753 | out_free: | |
689fd8b6 | 3754 | trace_parser_put(&parser); |
1eb90f13 | 3755 | out_unlock: |
ea4e2bc4 SR |
3756 | mutex_unlock(&graph_lock); |
3757 | ||
3758 | return ret; | |
3759 | } | |
3760 | ||
3761 | static const struct file_operations ftrace_graph_fops = { | |
87827111 LZ |
3762 | .open = ftrace_graph_open, |
3763 | .read = seq_read, | |
3764 | .write = ftrace_graph_write, | |
3765 | .release = ftrace_graph_release, | |
6038f373 | 3766 | .llseek = seq_lseek, |
ea4e2bc4 SR |
3767 | }; |
3768 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
3769 | ||
df4fc315 | 3770 | static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) |
5072c59f | 3771 | { |
5072c59f | 3772 | |
5452af66 FW |
3773 | trace_create_file("available_filter_functions", 0444, |
3774 | d_tracer, NULL, &ftrace_avail_fops); | |
5072c59f | 3775 | |
647bcd03 SR |
3776 | trace_create_file("enabled_functions", 0444, |
3777 | d_tracer, NULL, &ftrace_enabled_fops); | |
3778 | ||
5452af66 FW |
3779 | trace_create_file("set_ftrace_filter", 0644, d_tracer, |
3780 | NULL, &ftrace_filter_fops); | |
41c52c0d | 3781 | |
5452af66 | 3782 | trace_create_file("set_ftrace_notrace", 0644, d_tracer, |
41c52c0d | 3783 | NULL, &ftrace_notrace_fops); |
ad90c0e3 | 3784 | |
ea4e2bc4 | 3785 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5452af66 | 3786 | trace_create_file("set_graph_function", 0444, d_tracer, |
ea4e2bc4 SR |
3787 | NULL, |
3788 | &ftrace_graph_fops); | |
ea4e2bc4 SR |
3789 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
3790 | ||
5072c59f SR |
3791 | return 0; |
3792 | } | |
3793 | ||
9fd49328 | 3794 | static int ftrace_cmp_ips(const void *a, const void *b) |
68950619 | 3795 | { |
9fd49328 SR |
3796 | const unsigned long *ipa = a; |
3797 | const unsigned long *ipb = b; | |
68950619 | 3798 | |
9fd49328 SR |
3799 | if (*ipa > *ipb) |
3800 | return 1; | |
3801 | if (*ipa < *ipb) | |
3802 | return -1; | |
3803 | return 0; | |
3804 | } | |
3805 | ||
3806 | static void ftrace_swap_ips(void *a, void *b, int size) | |
3807 | { | |
3808 | unsigned long *ipa = a; | |
3809 | unsigned long *ipb = b; | |
3810 | unsigned long t; | |
3811 | ||
3812 | t = *ipa; | |
3813 | *ipa = *ipb; | |
3814 | *ipb = t; | |
68950619 SR |
3815 | } |
3816 | ||
5cb084bb | 3817 | static int ftrace_process_locs(struct module *mod, |
31e88909 | 3818 | unsigned long *start, |
68bf21aa SR |
3819 | unsigned long *end) |
3820 | { | |
706c81f8 | 3821 | struct ftrace_page *start_pg; |
a7900875 | 3822 | struct ftrace_page *pg; |
706c81f8 | 3823 | struct dyn_ftrace *rec; |
a7900875 | 3824 | unsigned long count; |
68bf21aa SR |
3825 | unsigned long *p; |
3826 | unsigned long addr; | |
4376cac6 | 3827 | unsigned long flags = 0; /* Shut up gcc */ |
a7900875 SR |
3828 | int ret = -ENOMEM; |
3829 | ||
3830 | count = end - start; | |
3831 | ||
3832 | if (!count) | |
3833 | return 0; | |
3834 | ||
9fd49328 SR |
3835 | sort(start, count, sizeof(*start), |
3836 | ftrace_cmp_ips, ftrace_swap_ips); | |
3837 | ||
706c81f8 SR |
3838 | start_pg = ftrace_allocate_pages(count); |
3839 | if (!start_pg) | |
a7900875 | 3840 | return -ENOMEM; |
68bf21aa | 3841 | |
e6ea44e9 | 3842 | mutex_lock(&ftrace_lock); |
a7900875 | 3843 | |
32082309 SR |
3844 | /* |
3845 | * Core and each module needs their own pages, as | |
3846 | * modules will free them when they are removed. | |
3847 | * Force a new page to be allocated for modules. | |
3848 | */ | |
a7900875 SR |
3849 | if (!mod) { |
3850 | WARN_ON(ftrace_pages || ftrace_pages_start); | |
3851 | /* First initialization */ | |
706c81f8 | 3852 | ftrace_pages = ftrace_pages_start = start_pg; |
a7900875 | 3853 | } else { |
32082309 | 3854 | if (!ftrace_pages) |
a7900875 | 3855 | goto out; |
32082309 | 3856 | |
a7900875 SR |
3857 | if (WARN_ON(ftrace_pages->next)) { |
3858 | /* Hmm, we have free pages? */ | |
3859 | while (ftrace_pages->next) | |
3860 | ftrace_pages = ftrace_pages->next; | |
32082309 | 3861 | } |
a7900875 | 3862 | |
706c81f8 | 3863 | ftrace_pages->next = start_pg; |
32082309 SR |
3864 | } |
3865 | ||
68bf21aa | 3866 | p = start; |
706c81f8 | 3867 | pg = start_pg; |
68bf21aa SR |
3868 | while (p < end) { |
3869 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
3870 | /* |
3871 | * Some architecture linkers will pad between | |
3872 | * the different mcount_loc sections of different | |
3873 | * object files to satisfy alignments. | |
3874 | * Skip any NULL pointers. | |
3875 | */ | |
3876 | if (!addr) | |
3877 | continue; | |
706c81f8 SR |
3878 | |
3879 | if (pg->index == pg->size) { | |
3880 | /* We should have allocated enough */ | |
3881 | if (WARN_ON(!pg->next)) | |
3882 | break; | |
3883 | pg = pg->next; | |
3884 | } | |
3885 | ||
3886 | rec = &pg->records[pg->index++]; | |
3887 | rec->ip = addr; | |
68bf21aa SR |
3888 | } |
3889 | ||
706c81f8 SR |
3890 | /* We should have used all pages */ |
3891 | WARN_ON(pg->next); | |
3892 | ||
3893 | /* Assign the last page to ftrace_pages */ | |
3894 | ftrace_pages = pg; | |
3895 | ||
85ae32ae | 3896 | /* These new locations need to be initialized */ |
706c81f8 | 3897 | ftrace_new_pgs = start_pg; |
85ae32ae | 3898 | |
a4f18ed1 | 3899 | /* |
4376cac6 SR |
3900 | * We only need to disable interrupts on start up |
3901 | * because we are modifying code that an interrupt | |
3902 | * may execute, and the modification is not atomic. | |
3903 | * But for modules, nothing runs the code we modify | |
3904 | * until we are finished with it, and there's no | |
3905 | * reason to cause large interrupt latencies while we do it. | |
a4f18ed1 | 3906 | */ |
4376cac6 SR |
3907 | if (!mod) |
3908 | local_irq_save(flags); | |
31e88909 | 3909 | ftrace_update_code(mod); |
4376cac6 SR |
3910 | if (!mod) |
3911 | local_irq_restore(flags); | |
a7900875 SR |
3912 | ret = 0; |
3913 | out: | |
e6ea44e9 | 3914 | mutex_unlock(&ftrace_lock); |
68bf21aa | 3915 | |
a7900875 | 3916 | return ret; |
68bf21aa SR |
3917 | } |
3918 | ||
93eb677d | 3919 | #ifdef CONFIG_MODULES |
32082309 SR |
3920 | |
3921 | #define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next) | |
3922 | ||
e7247a15 | 3923 | void ftrace_release_mod(struct module *mod) |
93eb677d SR |
3924 | { |
3925 | struct dyn_ftrace *rec; | |
32082309 | 3926 | struct ftrace_page **last_pg; |
93eb677d | 3927 | struct ftrace_page *pg; |
a7900875 | 3928 | int order; |
93eb677d | 3929 | |
45a4a237 SR |
3930 | mutex_lock(&ftrace_lock); |
3931 | ||
e7247a15 | 3932 | if (ftrace_disabled) |
45a4a237 | 3933 | goto out_unlock; |
93eb677d | 3934 | |
32082309 SR |
3935 | /* |
3936 | * Each module has its own ftrace_pages, remove | |
3937 | * them from the list. | |
3938 | */ | |
3939 | last_pg = &ftrace_pages_start; | |
3940 | for (pg = ftrace_pages_start; pg; pg = *last_pg) { | |
3941 | rec = &pg->records[0]; | |
e7247a15 | 3942 | if (within_module_core(rec->ip, mod)) { |
93eb677d | 3943 | /* |
32082309 SR |
3944 | * As core pages are first, the first |
3945 | * page should never be a module page. | |
93eb677d | 3946 | */ |
32082309 SR |
3947 | if (WARN_ON(pg == ftrace_pages_start)) |
3948 | goto out_unlock; | |
3949 | ||
3950 | /* Check if we are deleting the last page */ | |
3951 | if (pg == ftrace_pages) | |
3952 | ftrace_pages = next_to_ftrace_page(last_pg); | |
3953 | ||
3954 | *last_pg = pg->next; | |
a7900875 SR |
3955 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); |
3956 | free_pages((unsigned long)pg->records, order); | |
3957 | kfree(pg); | |
32082309 SR |
3958 | } else |
3959 | last_pg = &pg->next; | |
3960 | } | |
45a4a237 | 3961 | out_unlock: |
93eb677d SR |
3962 | mutex_unlock(&ftrace_lock); |
3963 | } | |
3964 | ||
3965 | static void ftrace_init_module(struct module *mod, | |
3966 | unsigned long *start, unsigned long *end) | |
90d595fe | 3967 | { |
00fd61ae | 3968 | if (ftrace_disabled || start == end) |
fed1939c | 3969 | return; |
5cb084bb | 3970 | ftrace_process_locs(mod, start, end); |
90d595fe SR |
3971 | } |
3972 | ||
93eb677d SR |
3973 | static int ftrace_module_notify(struct notifier_block *self, |
3974 | unsigned long val, void *data) | |
3975 | { | |
3976 | struct module *mod = data; | |
3977 | ||
3978 | switch (val) { | |
3979 | case MODULE_STATE_COMING: | |
3980 | ftrace_init_module(mod, mod->ftrace_callsites, | |
3981 | mod->ftrace_callsites + | |
3982 | mod->num_ftrace_callsites); | |
3983 | break; | |
3984 | case MODULE_STATE_GOING: | |
e7247a15 | 3985 | ftrace_release_mod(mod); |
93eb677d SR |
3986 | break; |
3987 | } | |
3988 | ||
3989 | return 0; | |
3990 | } | |
3991 | #else | |
3992 | static int ftrace_module_notify(struct notifier_block *self, | |
3993 | unsigned long val, void *data) | |
3994 | { | |
3995 | return 0; | |
3996 | } | |
3997 | #endif /* CONFIG_MODULES */ | |
3998 | ||
3999 | struct notifier_block ftrace_module_nb = { | |
4000 | .notifier_call = ftrace_module_notify, | |
4001 | .priority = 0, | |
4002 | }; | |
4003 | ||
68bf21aa SR |
4004 | extern unsigned long __start_mcount_loc[]; |
4005 | extern unsigned long __stop_mcount_loc[]; | |
4006 | ||
4007 | void __init ftrace_init(void) | |
4008 | { | |
4009 | unsigned long count, addr, flags; | |
4010 | int ret; | |
4011 | ||
4012 | /* Keep the ftrace pointer to the stub */ | |
4013 | addr = (unsigned long)ftrace_stub; | |
4014 | ||
4015 | local_irq_save(flags); | |
4016 | ftrace_dyn_arch_init(&addr); | |
4017 | local_irq_restore(flags); | |
4018 | ||
4019 | /* ftrace_dyn_arch_init places the return code in addr */ | |
4020 | if (addr) | |
4021 | goto failed; | |
4022 | ||
4023 | count = __stop_mcount_loc - __start_mcount_loc; | |
4024 | ||
4025 | ret = ftrace_dyn_table_alloc(count); | |
4026 | if (ret) | |
4027 | goto failed; | |
4028 | ||
4029 | last_ftrace_enabled = ftrace_enabled = 1; | |
4030 | ||
5cb084bb | 4031 | ret = ftrace_process_locs(NULL, |
31e88909 | 4032 | __start_mcount_loc, |
68bf21aa SR |
4033 | __stop_mcount_loc); |
4034 | ||
93eb677d | 4035 | ret = register_module_notifier(&ftrace_module_nb); |
24ed0c4b | 4036 | if (ret) |
93eb677d SR |
4037 | pr_warning("Failed to register trace ftrace module notifier\n"); |
4038 | ||
2af15d6a SR |
4039 | set_ftrace_early_filters(); |
4040 | ||
68bf21aa SR |
4041 | return; |
4042 | failed: | |
4043 | ftrace_disabled = 1; | |
4044 | } | |
68bf21aa | 4045 | |
3d083395 | 4046 | #else |
0b6e4d56 | 4047 | |
2b499381 | 4048 | static struct ftrace_ops global_ops = { |
bd69c30b | 4049 | .func = ftrace_stub, |
4740974a | 4050 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
bd69c30b SR |
4051 | }; |
4052 | ||
0b6e4d56 FW |
4053 | static int __init ftrace_nodyn_init(void) |
4054 | { | |
4055 | ftrace_enabled = 1; | |
4056 | return 0; | |
4057 | } | |
4058 | device_initcall(ftrace_nodyn_init); | |
4059 | ||
df4fc315 SR |
4060 | static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } |
4061 | static inline void ftrace_startup_enable(int command) { } | |
5a45cfe1 | 4062 | /* Keep as macros so we do not need to define the commands */ |
3b6cfdb1 SR |
4063 | # define ftrace_startup(ops, command) \ |
4064 | ({ \ | |
4065 | (ops)->flags |= FTRACE_OPS_FL_ENABLED; \ | |
4066 | 0; \ | |
4067 | }) | |
bd69c30b | 4068 | # define ftrace_shutdown(ops, command) do { } while (0) |
c7aafc54 IM |
4069 | # define ftrace_startup_sysctl() do { } while (0) |
4070 | # define ftrace_shutdown_sysctl() do { } while (0) | |
b848914c SR |
4071 | |
4072 | static inline int | |
4073 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip) | |
4074 | { | |
4075 | return 1; | |
4076 | } | |
4077 | ||
3d083395 SR |
4078 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
4079 | ||
e248491a | 4080 | static void |
2f5f6ad9 | 4081 | ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 4082 | struct ftrace_ops *op, struct pt_regs *regs) |
e248491a | 4083 | { |
e248491a JO |
4084 | if (unlikely(trace_recursion_test(TRACE_CONTROL_BIT))) |
4085 | return; | |
4086 | ||
4087 | /* | |
4088 | * Some of the ops may be dynamically allocated, | |
4089 | * they must be freed after a synchronize_sched(). | |
4090 | */ | |
4091 | preempt_disable_notrace(); | |
4092 | trace_recursion_set(TRACE_CONTROL_BIT); | |
4093 | op = rcu_dereference_raw(ftrace_control_list); | |
4094 | while (op != &ftrace_list_end) { | |
4095 | if (!ftrace_function_local_disabled(op) && | |
4096 | ftrace_ops_test(op, ip)) | |
a1e2e31d | 4097 | op->func(ip, parent_ip, op, regs); |
e248491a JO |
4098 | |
4099 | op = rcu_dereference_raw(op->next); | |
4100 | }; | |
4101 | trace_recursion_clear(TRACE_CONTROL_BIT); | |
4102 | preempt_enable_notrace(); | |
4103 | } | |
4104 | ||
4105 | static struct ftrace_ops control_ops = { | |
4106 | .func = ftrace_ops_control_func, | |
4740974a | 4107 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
e248491a JO |
4108 | }; |
4109 | ||
2f5f6ad9 SR |
4110 | static inline void |
4111 | __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 4112 | struct ftrace_ops *ignored, struct pt_regs *regs) |
b848914c | 4113 | { |
cdbe61bf | 4114 | struct ftrace_ops *op; |
b848914c | 4115 | |
ccf3672d SR |
4116 | if (function_trace_stop) |
4117 | return; | |
4118 | ||
b1cff0ad SR |
4119 | if (unlikely(trace_recursion_test(TRACE_INTERNAL_BIT))) |
4120 | return; | |
4121 | ||
4122 | trace_recursion_set(TRACE_INTERNAL_BIT); | |
cdbe61bf SR |
4123 | /* |
4124 | * Some of the ops may be dynamically allocated, | |
4125 | * they must be freed after a synchronize_sched(). | |
4126 | */ | |
4127 | preempt_disable_notrace(); | |
4128 | op = rcu_dereference_raw(ftrace_ops_list); | |
b848914c SR |
4129 | while (op != &ftrace_list_end) { |
4130 | if (ftrace_ops_test(op, ip)) | |
a1e2e31d | 4131 | op->func(ip, parent_ip, op, regs); |
b848914c SR |
4132 | op = rcu_dereference_raw(op->next); |
4133 | }; | |
cdbe61bf | 4134 | preempt_enable_notrace(); |
b1cff0ad | 4135 | trace_recursion_clear(TRACE_INTERNAL_BIT); |
b848914c SR |
4136 | } |
4137 | ||
2f5f6ad9 SR |
4138 | /* |
4139 | * Some archs only support passing ip and parent_ip. Even though | |
4140 | * the list function ignores the op parameter, we do not want any | |
4141 | * C side effects, where a function is called without the caller | |
4142 | * sending a third parameter. | |
a1e2e31d SR |
4143 | * Archs are to support both the regs and ftrace_ops at the same time. |
4144 | * If they support ftrace_ops, it is assumed they support regs. | |
4145 | * If call backs want to use regs, they must either check for regs | |
4146 | * being NULL, or ARCH_SUPPORTS_FTRACE_SAVE_REGS. | |
4147 | * Note, ARCH_SUPPORT_SAVE_REGS expects a full regs to be saved. | |
4148 | * An architecture can pass partial regs with ftrace_ops and still | |
4149 | * set the ARCH_SUPPORT_FTARCE_OPS. | |
2f5f6ad9 SR |
4150 | */ |
4151 | #if ARCH_SUPPORTS_FTRACE_OPS | |
4152 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 4153 | struct ftrace_ops *op, struct pt_regs *regs) |
2f5f6ad9 | 4154 | { |
a1e2e31d | 4155 | __ftrace_ops_list_func(ip, parent_ip, NULL, regs); |
2f5f6ad9 SR |
4156 | } |
4157 | #else | |
4158 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip) | |
4159 | { | |
a1e2e31d | 4160 | __ftrace_ops_list_func(ip, parent_ip, NULL, NULL); |
2f5f6ad9 SR |
4161 | } |
4162 | #endif | |
4163 | ||
e32d8956 | 4164 | static void clear_ftrace_swapper(void) |
978f3a45 SR |
4165 | { |
4166 | struct task_struct *p; | |
e32d8956 | 4167 | int cpu; |
978f3a45 | 4168 | |
e32d8956 SR |
4169 | get_online_cpus(); |
4170 | for_each_online_cpu(cpu) { | |
4171 | p = idle_task(cpu); | |
978f3a45 | 4172 | clear_tsk_trace_trace(p); |
e32d8956 SR |
4173 | } |
4174 | put_online_cpus(); | |
4175 | } | |
978f3a45 | 4176 | |
e32d8956 SR |
4177 | static void set_ftrace_swapper(void) |
4178 | { | |
4179 | struct task_struct *p; | |
4180 | int cpu; | |
4181 | ||
4182 | get_online_cpus(); | |
4183 | for_each_online_cpu(cpu) { | |
4184 | p = idle_task(cpu); | |
4185 | set_tsk_trace_trace(p); | |
4186 | } | |
4187 | put_online_cpus(); | |
978f3a45 SR |
4188 | } |
4189 | ||
e32d8956 SR |
4190 | static void clear_ftrace_pid(struct pid *pid) |
4191 | { | |
4192 | struct task_struct *p; | |
4193 | ||
229c4ef8 | 4194 | rcu_read_lock(); |
e32d8956 SR |
4195 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
4196 | clear_tsk_trace_trace(p); | |
4197 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 ON |
4198 | rcu_read_unlock(); |
4199 | ||
e32d8956 SR |
4200 | put_pid(pid); |
4201 | } | |
4202 | ||
4203 | static void set_ftrace_pid(struct pid *pid) | |
978f3a45 SR |
4204 | { |
4205 | struct task_struct *p; | |
4206 | ||
229c4ef8 | 4207 | rcu_read_lock(); |
978f3a45 SR |
4208 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
4209 | set_tsk_trace_trace(p); | |
4210 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 | 4211 | rcu_read_unlock(); |
978f3a45 SR |
4212 | } |
4213 | ||
756d17ee | 4214 | static void clear_ftrace_pid_task(struct pid *pid) |
e32d8956 | 4215 | { |
756d17ee | 4216 | if (pid == ftrace_swapper_pid) |
e32d8956 SR |
4217 | clear_ftrace_swapper(); |
4218 | else | |
756d17ee | 4219 | clear_ftrace_pid(pid); |
e32d8956 SR |
4220 | } |
4221 | ||
4222 | static void set_ftrace_pid_task(struct pid *pid) | |
4223 | { | |
4224 | if (pid == ftrace_swapper_pid) | |
4225 | set_ftrace_swapper(); | |
4226 | else | |
4227 | set_ftrace_pid(pid); | |
4228 | } | |
4229 | ||
756d17ee | 4230 | static int ftrace_pid_add(int p) |
df4fc315 | 4231 | { |
978f3a45 | 4232 | struct pid *pid; |
756d17ee | 4233 | struct ftrace_pid *fpid; |
4234 | int ret = -EINVAL; | |
df4fc315 | 4235 | |
756d17ee | 4236 | mutex_lock(&ftrace_lock); |
df4fc315 | 4237 | |
756d17ee | 4238 | if (!p) |
4239 | pid = ftrace_swapper_pid; | |
4240 | else | |
4241 | pid = find_get_pid(p); | |
df4fc315 | 4242 | |
756d17ee | 4243 | if (!pid) |
4244 | goto out; | |
df4fc315 | 4245 | |
756d17ee | 4246 | ret = 0; |
df4fc315 | 4247 | |
756d17ee | 4248 | list_for_each_entry(fpid, &ftrace_pids, list) |
4249 | if (fpid->pid == pid) | |
4250 | goto out_put; | |
978f3a45 | 4251 | |
756d17ee | 4252 | ret = -ENOMEM; |
df4fc315 | 4253 | |
756d17ee | 4254 | fpid = kmalloc(sizeof(*fpid), GFP_KERNEL); |
4255 | if (!fpid) | |
4256 | goto out_put; | |
df4fc315 | 4257 | |
756d17ee | 4258 | list_add(&fpid->list, &ftrace_pids); |
4259 | fpid->pid = pid; | |
0ef8cde5 | 4260 | |
756d17ee | 4261 | set_ftrace_pid_task(pid); |
978f3a45 | 4262 | |
756d17ee | 4263 | ftrace_update_pid_func(); |
4264 | ftrace_startup_enable(0); | |
4265 | ||
4266 | mutex_unlock(&ftrace_lock); | |
4267 | return 0; | |
4268 | ||
4269 | out_put: | |
4270 | if (pid != ftrace_swapper_pid) | |
4271 | put_pid(pid); | |
978f3a45 | 4272 | |
756d17ee | 4273 | out: |
4274 | mutex_unlock(&ftrace_lock); | |
4275 | return ret; | |
4276 | } | |
4277 | ||
4278 | static void ftrace_pid_reset(void) | |
4279 | { | |
4280 | struct ftrace_pid *fpid, *safe; | |
978f3a45 | 4281 | |
756d17ee | 4282 | mutex_lock(&ftrace_lock); |
4283 | list_for_each_entry_safe(fpid, safe, &ftrace_pids, list) { | |
4284 | struct pid *pid = fpid->pid; | |
4285 | ||
4286 | clear_ftrace_pid_task(pid); | |
4287 | ||
4288 | list_del(&fpid->list); | |
4289 | kfree(fpid); | |
df4fc315 SR |
4290 | } |
4291 | ||
df4fc315 SR |
4292 | ftrace_update_pid_func(); |
4293 | ftrace_startup_enable(0); | |
4294 | ||
e6ea44e9 | 4295 | mutex_unlock(&ftrace_lock); |
756d17ee | 4296 | } |
df4fc315 | 4297 | |
756d17ee | 4298 | static void *fpid_start(struct seq_file *m, loff_t *pos) |
4299 | { | |
4300 | mutex_lock(&ftrace_lock); | |
4301 | ||
4302 | if (list_empty(&ftrace_pids) && (!*pos)) | |
4303 | return (void *) 1; | |
4304 | ||
4305 | return seq_list_start(&ftrace_pids, *pos); | |
4306 | } | |
4307 | ||
4308 | static void *fpid_next(struct seq_file *m, void *v, loff_t *pos) | |
4309 | { | |
4310 | if (v == (void *)1) | |
4311 | return NULL; | |
4312 | ||
4313 | return seq_list_next(v, &ftrace_pids, pos); | |
4314 | } | |
4315 | ||
4316 | static void fpid_stop(struct seq_file *m, void *p) | |
4317 | { | |
4318 | mutex_unlock(&ftrace_lock); | |
4319 | } | |
4320 | ||
4321 | static int fpid_show(struct seq_file *m, void *v) | |
4322 | { | |
4323 | const struct ftrace_pid *fpid = list_entry(v, struct ftrace_pid, list); | |
4324 | ||
4325 | if (v == (void *)1) { | |
4326 | seq_printf(m, "no pid\n"); | |
4327 | return 0; | |
4328 | } | |
4329 | ||
4330 | if (fpid->pid == ftrace_swapper_pid) | |
4331 | seq_printf(m, "swapper tasks\n"); | |
4332 | else | |
4333 | seq_printf(m, "%u\n", pid_vnr(fpid->pid)); | |
4334 | ||
4335 | return 0; | |
4336 | } | |
4337 | ||
4338 | static const struct seq_operations ftrace_pid_sops = { | |
4339 | .start = fpid_start, | |
4340 | .next = fpid_next, | |
4341 | .stop = fpid_stop, | |
4342 | .show = fpid_show, | |
4343 | }; | |
4344 | ||
4345 | static int | |
4346 | ftrace_pid_open(struct inode *inode, struct file *file) | |
4347 | { | |
4348 | int ret = 0; | |
4349 | ||
4350 | if ((file->f_mode & FMODE_WRITE) && | |
4351 | (file->f_flags & O_TRUNC)) | |
4352 | ftrace_pid_reset(); | |
4353 | ||
4354 | if (file->f_mode & FMODE_READ) | |
4355 | ret = seq_open(file, &ftrace_pid_sops); | |
4356 | ||
4357 | return ret; | |
4358 | } | |
4359 | ||
df4fc315 SR |
4360 | static ssize_t |
4361 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
4362 | size_t cnt, loff_t *ppos) | |
4363 | { | |
457dc928 | 4364 | char buf[64], *tmp; |
df4fc315 SR |
4365 | long val; |
4366 | int ret; | |
4367 | ||
4368 | if (cnt >= sizeof(buf)) | |
4369 | return -EINVAL; | |
4370 | ||
4371 | if (copy_from_user(&buf, ubuf, cnt)) | |
4372 | return -EFAULT; | |
4373 | ||
4374 | buf[cnt] = 0; | |
4375 | ||
756d17ee | 4376 | /* |
4377 | * Allow "echo > set_ftrace_pid" or "echo -n '' > set_ftrace_pid" | |
4378 | * to clean the filter quietly. | |
4379 | */ | |
457dc928 IM |
4380 | tmp = strstrip(buf); |
4381 | if (strlen(tmp) == 0) | |
756d17ee | 4382 | return 1; |
4383 | ||
457dc928 | 4384 | ret = strict_strtol(tmp, 10, &val); |
df4fc315 SR |
4385 | if (ret < 0) |
4386 | return ret; | |
4387 | ||
756d17ee | 4388 | ret = ftrace_pid_add(val); |
df4fc315 | 4389 | |
756d17ee | 4390 | return ret ? ret : cnt; |
4391 | } | |
df4fc315 | 4392 | |
756d17ee | 4393 | static int |
4394 | ftrace_pid_release(struct inode *inode, struct file *file) | |
4395 | { | |
4396 | if (file->f_mode & FMODE_READ) | |
4397 | seq_release(inode, file); | |
df4fc315 | 4398 | |
756d17ee | 4399 | return 0; |
df4fc315 SR |
4400 | } |
4401 | ||
5e2336a0 | 4402 | static const struct file_operations ftrace_pid_fops = { |
756d17ee | 4403 | .open = ftrace_pid_open, |
4404 | .write = ftrace_pid_write, | |
4405 | .read = seq_read, | |
4406 | .llseek = seq_lseek, | |
4407 | .release = ftrace_pid_release, | |
df4fc315 SR |
4408 | }; |
4409 | ||
4410 | static __init int ftrace_init_debugfs(void) | |
4411 | { | |
4412 | struct dentry *d_tracer; | |
df4fc315 SR |
4413 | |
4414 | d_tracer = tracing_init_dentry(); | |
4415 | if (!d_tracer) | |
4416 | return 0; | |
4417 | ||
4418 | ftrace_init_dyn_debugfs(d_tracer); | |
4419 | ||
5452af66 FW |
4420 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
4421 | NULL, &ftrace_pid_fops); | |
493762fc SR |
4422 | |
4423 | ftrace_profile_debugfs(d_tracer); | |
4424 | ||
df4fc315 SR |
4425 | return 0; |
4426 | } | |
df4fc315 SR |
4427 | fs_initcall(ftrace_init_debugfs); |
4428 | ||
a2bb6a3d | 4429 | /** |
81adbdc0 | 4430 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
4431 | * |
4432 | * This function should be used by panic code. It stops ftrace | |
4433 | * but in a not so nice way. If you need to simply kill ftrace | |
4434 | * from a non-atomic section, use ftrace_kill. | |
4435 | */ | |
81adbdc0 | 4436 | void ftrace_kill(void) |
a2bb6a3d SR |
4437 | { |
4438 | ftrace_disabled = 1; | |
4439 | ftrace_enabled = 0; | |
a2bb6a3d SR |
4440 | clear_ftrace_function(); |
4441 | } | |
4442 | ||
e0a413f6 SR |
4443 | /** |
4444 | * Test if ftrace is dead or not. | |
4445 | */ | |
4446 | int ftrace_is_dead(void) | |
4447 | { | |
4448 | return ftrace_disabled; | |
4449 | } | |
4450 | ||
16444a8a | 4451 | /** |
3d083395 SR |
4452 | * register_ftrace_function - register a function for profiling |
4453 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 4454 | * |
3d083395 SR |
4455 | * Register a function to be called by all functions in the |
4456 | * kernel. | |
4457 | * | |
4458 | * Note: @ops->func and all the functions it calls must be labeled | |
4459 | * with "notrace", otherwise it will go into a | |
4460 | * recursive loop. | |
16444a8a | 4461 | */ |
3d083395 | 4462 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 4463 | { |
45a4a237 | 4464 | int ret = -1; |
4eebcc81 | 4465 | |
e6ea44e9 | 4466 | mutex_lock(&ftrace_lock); |
e7d3737e | 4467 | |
b0fc494f | 4468 | ret = __register_ftrace_function(ops); |
b848914c | 4469 | if (!ret) |
a1cd6173 | 4470 | ret = ftrace_startup(ops, 0); |
b848914c | 4471 | |
e6ea44e9 | 4472 | mutex_unlock(&ftrace_lock); |
8d240dd8 | 4473 | |
b0fc494f | 4474 | return ret; |
3d083395 | 4475 | } |
cdbe61bf | 4476 | EXPORT_SYMBOL_GPL(register_ftrace_function); |
3d083395 SR |
4477 | |
4478 | /** | |
32632920 | 4479 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
4480 | * @ops - ops structure that holds the function to unregister |
4481 | * | |
4482 | * Unregister a function that was added to be called by ftrace profiling. | |
4483 | */ | |
4484 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
4485 | { | |
4486 | int ret; | |
4487 | ||
e6ea44e9 | 4488 | mutex_lock(&ftrace_lock); |
3d083395 | 4489 | ret = __unregister_ftrace_function(ops); |
b848914c SR |
4490 | if (!ret) |
4491 | ftrace_shutdown(ops, 0); | |
e6ea44e9 | 4492 | mutex_unlock(&ftrace_lock); |
b0fc494f SR |
4493 | |
4494 | return ret; | |
4495 | } | |
cdbe61bf | 4496 | EXPORT_SYMBOL_GPL(unregister_ftrace_function); |
b0fc494f | 4497 | |
e309b41d | 4498 | int |
b0fc494f | 4499 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
8d65af78 | 4500 | void __user *buffer, size_t *lenp, |
b0fc494f SR |
4501 | loff_t *ppos) |
4502 | { | |
45a4a237 | 4503 | int ret = -ENODEV; |
4eebcc81 | 4504 | |
e6ea44e9 | 4505 | mutex_lock(&ftrace_lock); |
b0fc494f | 4506 | |
45a4a237 SR |
4507 | if (unlikely(ftrace_disabled)) |
4508 | goto out; | |
4509 | ||
4510 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
b0fc494f | 4511 | |
a32c7765 | 4512 | if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) |
b0fc494f SR |
4513 | goto out; |
4514 | ||
a32c7765 | 4515 | last_ftrace_enabled = !!ftrace_enabled; |
b0fc494f SR |
4516 | |
4517 | if (ftrace_enabled) { | |
4518 | ||
4519 | ftrace_startup_sysctl(); | |
4520 | ||
4521 | /* we are starting ftrace again */ | |
b848914c SR |
4522 | if (ftrace_ops_list != &ftrace_list_end) { |
4523 | if (ftrace_ops_list->next == &ftrace_list_end) | |
4524 | ftrace_trace_function = ftrace_ops_list->func; | |
b0fc494f | 4525 | else |
b848914c | 4526 | ftrace_trace_function = ftrace_ops_list_func; |
b0fc494f SR |
4527 | } |
4528 | ||
4529 | } else { | |
4530 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
4531 | ftrace_trace_function = ftrace_stub; | |
4532 | ||
4533 | ftrace_shutdown_sysctl(); | |
4534 | } | |
4535 | ||
4536 | out: | |
e6ea44e9 | 4537 | mutex_unlock(&ftrace_lock); |
3d083395 | 4538 | return ret; |
16444a8a | 4539 | } |
f17845e5 | 4540 | |
fb52607a | 4541 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 4542 | |
597af815 | 4543 | static int ftrace_graph_active; |
4a2b8dda | 4544 | static struct notifier_block ftrace_suspend_notifier; |
e7d3737e | 4545 | |
e49dc19c SR |
4546 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
4547 | { | |
4548 | return 0; | |
4549 | } | |
4550 | ||
287b6e68 FW |
4551 | /* The callbacks that hook a function */ |
4552 | trace_func_graph_ret_t ftrace_graph_return = | |
4553 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 4554 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
4555 | |
4556 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
4557 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
4558 | { | |
4559 | int i; | |
4560 | int ret = 0; | |
4561 | unsigned long flags; | |
4562 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; | |
4563 | struct task_struct *g, *t; | |
4564 | ||
4565 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
4566 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
4567 | * sizeof(struct ftrace_ret_stack), | |
4568 | GFP_KERNEL); | |
4569 | if (!ret_stack_list[i]) { | |
4570 | start = 0; | |
4571 | end = i; | |
4572 | ret = -ENOMEM; | |
4573 | goto free; | |
4574 | } | |
4575 | } | |
4576 | ||
4577 | read_lock_irqsave(&tasklist_lock, flags); | |
4578 | do_each_thread(g, t) { | |
4579 | if (start == end) { | |
4580 | ret = -EAGAIN; | |
4581 | goto unlock; | |
4582 | } | |
4583 | ||
4584 | if (t->ret_stack == NULL) { | |
380c4b14 | 4585 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 | 4586 | atomic_set(&t->trace_overrun, 0); |
26c01624 SR |
4587 | t->curr_ret_stack = -1; |
4588 | /* Make sure the tasks see the -1 first: */ | |
4589 | smp_wmb(); | |
4590 | t->ret_stack = ret_stack_list[start++]; | |
f201ae23 FW |
4591 | } |
4592 | } while_each_thread(g, t); | |
4593 | ||
4594 | unlock: | |
4595 | read_unlock_irqrestore(&tasklist_lock, flags); | |
4596 | free: | |
4597 | for (i = start; i < end; i++) | |
4598 | kfree(ret_stack_list[i]); | |
4599 | return ret; | |
4600 | } | |
4601 | ||
8aef2d28 | 4602 | static void |
38516ab5 SR |
4603 | ftrace_graph_probe_sched_switch(void *ignore, |
4604 | struct task_struct *prev, struct task_struct *next) | |
8aef2d28 SR |
4605 | { |
4606 | unsigned long long timestamp; | |
4607 | int index; | |
4608 | ||
be6f164a SR |
4609 | /* |
4610 | * Does the user want to count the time a function was asleep. | |
4611 | * If so, do not update the time stamps. | |
4612 | */ | |
4613 | if (trace_flags & TRACE_ITER_SLEEP_TIME) | |
4614 | return; | |
4615 | ||
8aef2d28 SR |
4616 | timestamp = trace_clock_local(); |
4617 | ||
4618 | prev->ftrace_timestamp = timestamp; | |
4619 | ||
4620 | /* only process tasks that we timestamped */ | |
4621 | if (!next->ftrace_timestamp) | |
4622 | return; | |
4623 | ||
4624 | /* | |
4625 | * Update all the counters in next to make up for the | |
4626 | * time next was sleeping. | |
4627 | */ | |
4628 | timestamp -= next->ftrace_timestamp; | |
4629 | ||
4630 | for (index = next->curr_ret_stack; index >= 0; index--) | |
4631 | next->ret_stack[index].calltime += timestamp; | |
4632 | } | |
4633 | ||
f201ae23 | 4634 | /* Allocate a return stack for each task */ |
fb52607a | 4635 | static int start_graph_tracing(void) |
f201ae23 FW |
4636 | { |
4637 | struct ftrace_ret_stack **ret_stack_list; | |
5b058bcd | 4638 | int ret, cpu; |
f201ae23 FW |
4639 | |
4640 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
4641 | sizeof(struct ftrace_ret_stack *), | |
4642 | GFP_KERNEL); | |
4643 | ||
4644 | if (!ret_stack_list) | |
4645 | return -ENOMEM; | |
4646 | ||
5b058bcd | 4647 | /* The cpu_boot init_task->ret_stack will never be freed */ |
179c498a SR |
4648 | for_each_online_cpu(cpu) { |
4649 | if (!idle_task(cpu)->ret_stack) | |
868baf07 | 4650 | ftrace_graph_init_idle_task(idle_task(cpu), cpu); |
179c498a | 4651 | } |
5b058bcd | 4652 | |
f201ae23 FW |
4653 | do { |
4654 | ret = alloc_retstack_tasklist(ret_stack_list); | |
4655 | } while (ret == -EAGAIN); | |
4656 | ||
8aef2d28 | 4657 | if (!ret) { |
38516ab5 | 4658 | ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
8aef2d28 SR |
4659 | if (ret) |
4660 | pr_info("ftrace_graph: Couldn't activate tracepoint" | |
4661 | " probe to kernel_sched_switch\n"); | |
4662 | } | |
4663 | ||
f201ae23 FW |
4664 | kfree(ret_stack_list); |
4665 | return ret; | |
4666 | } | |
4667 | ||
4a2b8dda FW |
4668 | /* |
4669 | * Hibernation protection. | |
4670 | * The state of the current task is too much unstable during | |
4671 | * suspend/restore to disk. We want to protect against that. | |
4672 | */ | |
4673 | static int | |
4674 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, | |
4675 | void *unused) | |
4676 | { | |
4677 | switch (state) { | |
4678 | case PM_HIBERNATION_PREPARE: | |
4679 | pause_graph_tracing(); | |
4680 | break; | |
4681 | ||
4682 | case PM_POST_HIBERNATION: | |
4683 | unpause_graph_tracing(); | |
4684 | break; | |
4685 | } | |
4686 | return NOTIFY_DONE; | |
4687 | } | |
4688 | ||
287b6e68 FW |
4689 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
4690 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 4691 | { |
e7d3737e FW |
4692 | int ret = 0; |
4693 | ||
e6ea44e9 | 4694 | mutex_lock(&ftrace_lock); |
e7d3737e | 4695 | |
05ce5818 | 4696 | /* we currently allow only one tracer registered at a time */ |
597af815 | 4697 | if (ftrace_graph_active) { |
05ce5818 SR |
4698 | ret = -EBUSY; |
4699 | goto out; | |
4700 | } | |
4701 | ||
4a2b8dda FW |
4702 | ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call; |
4703 | register_pm_notifier(&ftrace_suspend_notifier); | |
4704 | ||
597af815 | 4705 | ftrace_graph_active++; |
fb52607a | 4706 | ret = start_graph_tracing(); |
f201ae23 | 4707 | if (ret) { |
597af815 | 4708 | ftrace_graph_active--; |
f201ae23 FW |
4709 | goto out; |
4710 | } | |
e53a6319 | 4711 | |
287b6e68 FW |
4712 | ftrace_graph_return = retfunc; |
4713 | ftrace_graph_entry = entryfunc; | |
e53a6319 | 4714 | |
a1cd6173 | 4715 | ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET); |
e7d3737e FW |
4716 | |
4717 | out: | |
e6ea44e9 | 4718 | mutex_unlock(&ftrace_lock); |
e7d3737e | 4719 | return ret; |
15e6cb36 FW |
4720 | } |
4721 | ||
fb52607a | 4722 | void unregister_ftrace_graph(void) |
15e6cb36 | 4723 | { |
e6ea44e9 | 4724 | mutex_lock(&ftrace_lock); |
e7d3737e | 4725 | |
597af815 | 4726 | if (unlikely(!ftrace_graph_active)) |
2aad1b76 SR |
4727 | goto out; |
4728 | ||
597af815 | 4729 | ftrace_graph_active--; |
287b6e68 | 4730 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; |
e49dc19c | 4731 | ftrace_graph_entry = ftrace_graph_entry_stub; |
bd69c30b | 4732 | ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET); |
4a2b8dda | 4733 | unregister_pm_notifier(&ftrace_suspend_notifier); |
38516ab5 | 4734 | unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
e7d3737e | 4735 | |
2aad1b76 | 4736 | out: |
e6ea44e9 | 4737 | mutex_unlock(&ftrace_lock); |
15e6cb36 | 4738 | } |
f201ae23 | 4739 | |
868baf07 SR |
4740 | static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack); |
4741 | ||
4742 | static void | |
4743 | graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack) | |
4744 | { | |
4745 | atomic_set(&t->tracing_graph_pause, 0); | |
4746 | atomic_set(&t->trace_overrun, 0); | |
4747 | t->ftrace_timestamp = 0; | |
25985edc | 4748 | /* make curr_ret_stack visible before we add the ret_stack */ |
868baf07 SR |
4749 | smp_wmb(); |
4750 | t->ret_stack = ret_stack; | |
4751 | } | |
4752 | ||
4753 | /* | |
4754 | * Allocate a return stack for the idle task. May be the first | |
4755 | * time through, or it may be done by CPU hotplug online. | |
4756 | */ | |
4757 | void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) | |
4758 | { | |
4759 | t->curr_ret_stack = -1; | |
4760 | /* | |
4761 | * The idle task has no parent, it either has its own | |
4762 | * stack or no stack at all. | |
4763 | */ | |
4764 | if (t->ret_stack) | |
4765 | WARN_ON(t->ret_stack != per_cpu(idle_ret_stack, cpu)); | |
4766 | ||
4767 | if (ftrace_graph_active) { | |
4768 | struct ftrace_ret_stack *ret_stack; | |
4769 | ||
4770 | ret_stack = per_cpu(idle_ret_stack, cpu); | |
4771 | if (!ret_stack) { | |
4772 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
4773 | * sizeof(struct ftrace_ret_stack), | |
4774 | GFP_KERNEL); | |
4775 | if (!ret_stack) | |
4776 | return; | |
4777 | per_cpu(idle_ret_stack, cpu) = ret_stack; | |
4778 | } | |
4779 | graph_init_task(t, ret_stack); | |
4780 | } | |
4781 | } | |
4782 | ||
f201ae23 | 4783 | /* Allocate a return stack for newly created task */ |
fb52607a | 4784 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 4785 | { |
84047e36 SR |
4786 | /* Make sure we do not use the parent ret_stack */ |
4787 | t->ret_stack = NULL; | |
ea14eb71 | 4788 | t->curr_ret_stack = -1; |
84047e36 | 4789 | |
597af815 | 4790 | if (ftrace_graph_active) { |
82310a32 SR |
4791 | struct ftrace_ret_stack *ret_stack; |
4792 | ||
4793 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
f201ae23 FW |
4794 | * sizeof(struct ftrace_ret_stack), |
4795 | GFP_KERNEL); | |
82310a32 | 4796 | if (!ret_stack) |
f201ae23 | 4797 | return; |
868baf07 | 4798 | graph_init_task(t, ret_stack); |
84047e36 | 4799 | } |
f201ae23 FW |
4800 | } |
4801 | ||
fb52607a | 4802 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 4803 | { |
eae849ca FW |
4804 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
4805 | ||
f201ae23 | 4806 | t->ret_stack = NULL; |
eae849ca FW |
4807 | /* NULL must become visible to IRQs before we free it: */ |
4808 | barrier(); | |
4809 | ||
4810 | kfree(ret_stack); | |
f201ae23 | 4811 | } |
14a866c5 SR |
4812 | |
4813 | void ftrace_graph_stop(void) | |
4814 | { | |
4815 | ftrace_stop(); | |
4816 | } | |
15e6cb36 | 4817 | #endif |