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 | |
6d49e352 | 13 | * Copyright (C) 2004 Nadia Yvette Chambers |
16444a8a ACM |
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 | 223 | if (ftrace_global_list == &ftrace_list_end || |
63503794 | 224 | ftrace_global_list->next == &ftrace_list_end) { |
b848914c | 225 | func = ftrace_global_list->func; |
63503794 SR |
226 | /* |
227 | * As we are calling the function directly. | |
228 | * If it does not have recursion protection, | |
229 | * the function_trace_op needs to be updated | |
230 | * accordingly. | |
231 | */ | |
232 | if (ftrace_global_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) | |
233 | global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE; | |
234 | else | |
235 | global_ops.flags &= ~FTRACE_OPS_FL_RECURSION_SAFE; | |
236 | } else { | |
b848914c | 237 | func = ftrace_global_list_func; |
63503794 SR |
238 | /* The list has its own recursion protection. */ |
239 | global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE; | |
240 | } | |
241 | ||
491d0dcf SR |
242 | |
243 | /* If we filter on pids, update to use the pid function */ | |
244 | if (!list_empty(&ftrace_pids)) { | |
245 | set_ftrace_pid_function(func); | |
246 | func = ftrace_pid_func; | |
247 | } | |
2b499381 SR |
248 | |
249 | global_ops.func = func; | |
250 | } | |
251 | ||
252 | static void update_ftrace_function(void) | |
253 | { | |
254 | ftrace_func_t func; | |
255 | ||
256 | update_global_ops(); | |
257 | ||
cdbe61bf SR |
258 | /* |
259 | * If we are at the end of the list and this ops is | |
4740974a SR |
260 | * recursion safe and not dynamic and the arch supports passing ops, |
261 | * then have the mcount trampoline call the function directly. | |
cdbe61bf | 262 | */ |
b848914c | 263 | if (ftrace_ops_list == &ftrace_list_end || |
cdbe61bf | 264 | (ftrace_ops_list->next == &ftrace_list_end && |
2f5f6ad9 | 265 | !(ftrace_ops_list->flags & FTRACE_OPS_FL_DYNAMIC) && |
4740974a | 266 | (ftrace_ops_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) && |
ccf3672d | 267 | !FTRACE_FORCE_LIST_FUNC)) { |
2f5f6ad9 SR |
268 | /* Set the ftrace_ops that the arch callback uses */ |
269 | if (ftrace_ops_list == &global_ops) | |
270 | function_trace_op = ftrace_global_list; | |
271 | else | |
272 | function_trace_op = ftrace_ops_list; | |
b848914c | 273 | func = ftrace_ops_list->func; |
2f5f6ad9 SR |
274 | } else { |
275 | /* Just use the default ftrace_ops */ | |
276 | function_trace_op = &ftrace_list_end; | |
b848914c | 277 | func = ftrace_ops_list_func; |
2f5f6ad9 | 278 | } |
2b499381 | 279 | |
491d0dcf | 280 | ftrace_trace_function = func; |
491d0dcf SR |
281 | } |
282 | ||
2b499381 | 283 | static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
3d083395 | 284 | { |
2b499381 | 285 | ops->next = *list; |
16444a8a | 286 | /* |
b848914c | 287 | * We are entering ops into the list but another |
16444a8a ACM |
288 | * CPU might be walking that list. We need to make sure |
289 | * the ops->next pointer is valid before another CPU sees | |
b848914c | 290 | * the ops pointer included into the list. |
16444a8a | 291 | */ |
2b499381 | 292 | rcu_assign_pointer(*list, ops); |
16444a8a ACM |
293 | } |
294 | ||
2b499381 | 295 | static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
16444a8a | 296 | { |
16444a8a | 297 | struct ftrace_ops **p; |
16444a8a ACM |
298 | |
299 | /* | |
3d083395 SR |
300 | * If we are removing the last function, then simply point |
301 | * to the ftrace_stub. | |
16444a8a | 302 | */ |
2b499381 SR |
303 | if (*list == ops && ops->next == &ftrace_list_end) { |
304 | *list = &ftrace_list_end; | |
e6ea44e9 | 305 | return 0; |
16444a8a ACM |
306 | } |
307 | ||
2b499381 | 308 | for (p = list; *p != &ftrace_list_end; p = &(*p)->next) |
16444a8a ACM |
309 | if (*p == ops) |
310 | break; | |
311 | ||
e6ea44e9 SR |
312 | if (*p != ops) |
313 | return -1; | |
16444a8a ACM |
314 | |
315 | *p = (*p)->next; | |
2b499381 SR |
316 | return 0; |
317 | } | |
16444a8a | 318 | |
e248491a JO |
319 | static void add_ftrace_list_ops(struct ftrace_ops **list, |
320 | struct ftrace_ops *main_ops, | |
321 | struct ftrace_ops *ops) | |
322 | { | |
323 | int first = *list == &ftrace_list_end; | |
324 | add_ftrace_ops(list, ops); | |
325 | if (first) | |
326 | add_ftrace_ops(&ftrace_ops_list, main_ops); | |
327 | } | |
328 | ||
329 | static int remove_ftrace_list_ops(struct ftrace_ops **list, | |
330 | struct ftrace_ops *main_ops, | |
331 | struct ftrace_ops *ops) | |
332 | { | |
333 | int ret = remove_ftrace_ops(list, ops); | |
334 | if (!ret && *list == &ftrace_list_end) | |
335 | ret = remove_ftrace_ops(&ftrace_ops_list, main_ops); | |
336 | return ret; | |
337 | } | |
338 | ||
2b499381 SR |
339 | static int __register_ftrace_function(struct ftrace_ops *ops) |
340 | { | |
8d240dd8 | 341 | if (unlikely(ftrace_disabled)) |
2b499381 SR |
342 | return -ENODEV; |
343 | ||
344 | if (FTRACE_WARN_ON(ops == &global_ops)) | |
345 | return -EINVAL; | |
346 | ||
b848914c SR |
347 | if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED)) |
348 | return -EBUSY; | |
349 | ||
e248491a JO |
350 | /* We don't support both control and global flags set. */ |
351 | if ((ops->flags & FL_GLOBAL_CONTROL_MASK) == FL_GLOBAL_CONTROL_MASK) | |
352 | return -EINVAL; | |
353 | ||
06aeaaea | 354 | #ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
08f6fba5 SR |
355 | /* |
356 | * If the ftrace_ops specifies SAVE_REGS, then it only can be used | |
357 | * if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set. | |
358 | * Setting SAVE_REGS_IF_SUPPORTED makes SAVE_REGS irrelevant. | |
359 | */ | |
360 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS && | |
361 | !(ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)) | |
362 | return -EINVAL; | |
363 | ||
364 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED) | |
365 | ops->flags |= FTRACE_OPS_FL_SAVE_REGS; | |
366 | #endif | |
367 | ||
cdbe61bf SR |
368 | if (!core_kernel_data((unsigned long)ops)) |
369 | ops->flags |= FTRACE_OPS_FL_DYNAMIC; | |
370 | ||
b848914c | 371 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
e248491a | 372 | add_ftrace_list_ops(&ftrace_global_list, &global_ops, ops); |
b848914c | 373 | ops->flags |= FTRACE_OPS_FL_ENABLED; |
e248491a JO |
374 | } else if (ops->flags & FTRACE_OPS_FL_CONTROL) { |
375 | if (control_ops_alloc(ops)) | |
376 | return -ENOMEM; | |
377 | add_ftrace_list_ops(&ftrace_control_list, &control_ops, ops); | |
b848914c SR |
378 | } else |
379 | add_ftrace_ops(&ftrace_ops_list, ops); | |
380 | ||
2b499381 SR |
381 | if (ftrace_enabled) |
382 | update_ftrace_function(); | |
383 | ||
384 | return 0; | |
385 | } | |
386 | ||
387 | static int __unregister_ftrace_function(struct ftrace_ops *ops) | |
388 | { | |
389 | int ret; | |
390 | ||
391 | if (ftrace_disabled) | |
392 | return -ENODEV; | |
393 | ||
b848914c SR |
394 | if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) |
395 | return -EBUSY; | |
396 | ||
2b499381 SR |
397 | if (FTRACE_WARN_ON(ops == &global_ops)) |
398 | return -EINVAL; | |
399 | ||
b848914c | 400 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
e248491a JO |
401 | ret = remove_ftrace_list_ops(&ftrace_global_list, |
402 | &global_ops, ops); | |
b848914c SR |
403 | if (!ret) |
404 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; | |
e248491a JO |
405 | } else if (ops->flags & FTRACE_OPS_FL_CONTROL) { |
406 | ret = remove_ftrace_list_ops(&ftrace_control_list, | |
407 | &control_ops, ops); | |
408 | if (!ret) { | |
409 | /* | |
410 | * The ftrace_ops is now removed from the list, | |
411 | * so there'll be no new users. We must ensure | |
412 | * all current users are done before we free | |
413 | * the control data. | |
414 | */ | |
415 | synchronize_sched(); | |
416 | control_ops_free(ops); | |
417 | } | |
b848914c SR |
418 | } else |
419 | ret = remove_ftrace_ops(&ftrace_ops_list, ops); | |
420 | ||
2b499381 SR |
421 | if (ret < 0) |
422 | return ret; | |
b848914c | 423 | |
491d0dcf SR |
424 | if (ftrace_enabled) |
425 | update_ftrace_function(); | |
16444a8a | 426 | |
cdbe61bf SR |
427 | /* |
428 | * Dynamic ops may be freed, we must make sure that all | |
429 | * callers are done before leaving this function. | |
430 | */ | |
431 | if (ops->flags & FTRACE_OPS_FL_DYNAMIC) | |
432 | synchronize_sched(); | |
433 | ||
e6ea44e9 | 434 | return 0; |
3d083395 SR |
435 | } |
436 | ||
df4fc315 SR |
437 | static void ftrace_update_pid_func(void) |
438 | { | |
491d0dcf | 439 | /* Only do something if we are tracing something */ |
df4fc315 | 440 | if (ftrace_trace_function == ftrace_stub) |
10dd3ebe | 441 | return; |
df4fc315 | 442 | |
491d0dcf | 443 | update_ftrace_function(); |
df4fc315 SR |
444 | } |
445 | ||
493762fc SR |
446 | #ifdef CONFIG_FUNCTION_PROFILER |
447 | struct ftrace_profile { | |
448 | struct hlist_node node; | |
449 | unsigned long ip; | |
450 | unsigned long counter; | |
0706f1c4 SR |
451 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
452 | unsigned long long time; | |
e330b3bc | 453 | unsigned long long time_squared; |
0706f1c4 | 454 | #endif |
8fc0c701 SR |
455 | }; |
456 | ||
493762fc SR |
457 | struct ftrace_profile_page { |
458 | struct ftrace_profile_page *next; | |
459 | unsigned long index; | |
460 | struct ftrace_profile records[]; | |
d61f82d0 SR |
461 | }; |
462 | ||
cafb168a SR |
463 | struct ftrace_profile_stat { |
464 | atomic_t disabled; | |
465 | struct hlist_head *hash; | |
466 | struct ftrace_profile_page *pages; | |
467 | struct ftrace_profile_page *start; | |
468 | struct tracer_stat stat; | |
469 | }; | |
470 | ||
493762fc SR |
471 | #define PROFILE_RECORDS_SIZE \ |
472 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | |
5072c59f | 473 | |
493762fc SR |
474 | #define PROFILES_PER_PAGE \ |
475 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | |
3d083395 | 476 | |
fb9fb015 SR |
477 | static int ftrace_profile_bits __read_mostly; |
478 | static int ftrace_profile_enabled __read_mostly; | |
479 | ||
480 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ | |
bac429f0 SR |
481 | static DEFINE_MUTEX(ftrace_profile_lock); |
482 | ||
cafb168a | 483 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); |
493762fc SR |
484 | |
485 | #define FTRACE_PROFILE_HASH_SIZE 1024 /* must be power of 2 */ | |
486 | ||
bac429f0 SR |
487 | static void * |
488 | function_stat_next(void *v, int idx) | |
489 | { | |
493762fc SR |
490 | struct ftrace_profile *rec = v; |
491 | struct ftrace_profile_page *pg; | |
bac429f0 | 492 | |
493762fc | 493 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
bac429f0 SR |
494 | |
495 | again: | |
0296e425 LZ |
496 | if (idx != 0) |
497 | rec++; | |
498 | ||
bac429f0 SR |
499 | if ((void *)rec >= (void *)&pg->records[pg->index]) { |
500 | pg = pg->next; | |
501 | if (!pg) | |
502 | return NULL; | |
503 | rec = &pg->records[0]; | |
493762fc SR |
504 | if (!rec->counter) |
505 | goto again; | |
bac429f0 SR |
506 | } |
507 | ||
bac429f0 SR |
508 | return rec; |
509 | } | |
510 | ||
511 | static void *function_stat_start(struct tracer_stat *trace) | |
512 | { | |
cafb168a SR |
513 | struct ftrace_profile_stat *stat = |
514 | container_of(trace, struct ftrace_profile_stat, stat); | |
515 | ||
516 | if (!stat || !stat->start) | |
517 | return NULL; | |
518 | ||
519 | return function_stat_next(&stat->start->records[0], 0); | |
bac429f0 SR |
520 | } |
521 | ||
0706f1c4 SR |
522 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
523 | /* function graph compares on total time */ | |
524 | static int function_stat_cmp(void *p1, void *p2) | |
525 | { | |
526 | struct ftrace_profile *a = p1; | |
527 | struct ftrace_profile *b = p2; | |
528 | ||
529 | if (a->time < b->time) | |
530 | return -1; | |
531 | if (a->time > b->time) | |
532 | return 1; | |
533 | else | |
534 | return 0; | |
535 | } | |
536 | #else | |
537 | /* not function graph compares against hits */ | |
bac429f0 SR |
538 | static int function_stat_cmp(void *p1, void *p2) |
539 | { | |
493762fc SR |
540 | struct ftrace_profile *a = p1; |
541 | struct ftrace_profile *b = p2; | |
bac429f0 SR |
542 | |
543 | if (a->counter < b->counter) | |
544 | return -1; | |
545 | if (a->counter > b->counter) | |
546 | return 1; | |
547 | else | |
548 | return 0; | |
549 | } | |
0706f1c4 | 550 | #endif |
bac429f0 SR |
551 | |
552 | static int function_stat_headers(struct seq_file *m) | |
553 | { | |
0706f1c4 | 554 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b | 555 | seq_printf(m, " Function " |
e330b3bc | 556 | "Hit Time Avg s^2\n" |
34886c8b | 557 | " -------- " |
e330b3bc | 558 | "--- ---- --- ---\n"); |
0706f1c4 | 559 | #else |
bac429f0 SR |
560 | seq_printf(m, " Function Hit\n" |
561 | " -------- ---\n"); | |
0706f1c4 | 562 | #endif |
bac429f0 SR |
563 | return 0; |
564 | } | |
565 | ||
566 | static int function_stat_show(struct seq_file *m, void *v) | |
567 | { | |
493762fc | 568 | struct ftrace_profile *rec = v; |
bac429f0 | 569 | char str[KSYM_SYMBOL_LEN]; |
3aaba20f | 570 | int ret = 0; |
0706f1c4 | 571 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b SR |
572 | static struct trace_seq s; |
573 | unsigned long long avg; | |
e330b3bc | 574 | unsigned long long stddev; |
0706f1c4 | 575 | #endif |
3aaba20f LZ |
576 | mutex_lock(&ftrace_profile_lock); |
577 | ||
578 | /* we raced with function_profile_reset() */ | |
579 | if (unlikely(rec->counter == 0)) { | |
580 | ret = -EBUSY; | |
581 | goto out; | |
582 | } | |
bac429f0 SR |
583 | |
584 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
0706f1c4 SR |
585 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); |
586 | ||
587 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
588 | seq_printf(m, " "); | |
34886c8b SR |
589 | avg = rec->time; |
590 | do_div(avg, rec->counter); | |
591 | ||
e330b3bc CD |
592 | /* Sample standard deviation (s^2) */ |
593 | if (rec->counter <= 1) | |
594 | stddev = 0; | |
595 | else { | |
596 | stddev = rec->time_squared - rec->counter * avg * avg; | |
597 | /* | |
598 | * Divide only 1000 for ns^2 -> us^2 conversion. | |
599 | * trace_print_graph_duration will divide 1000 again. | |
600 | */ | |
601 | do_div(stddev, (rec->counter - 1) * 1000); | |
602 | } | |
603 | ||
34886c8b SR |
604 | trace_seq_init(&s); |
605 | trace_print_graph_duration(rec->time, &s); | |
606 | trace_seq_puts(&s, " "); | |
607 | trace_print_graph_duration(avg, &s); | |
e330b3bc CD |
608 | trace_seq_puts(&s, " "); |
609 | trace_print_graph_duration(stddev, &s); | |
0706f1c4 | 610 | trace_print_seq(m, &s); |
0706f1c4 SR |
611 | #endif |
612 | seq_putc(m, '\n'); | |
3aaba20f LZ |
613 | out: |
614 | mutex_unlock(&ftrace_profile_lock); | |
bac429f0 | 615 | |
3aaba20f | 616 | return ret; |
bac429f0 SR |
617 | } |
618 | ||
cafb168a | 619 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) |
bac429f0 | 620 | { |
493762fc | 621 | struct ftrace_profile_page *pg; |
bac429f0 | 622 | |
cafb168a | 623 | pg = stat->pages = stat->start; |
bac429f0 | 624 | |
493762fc SR |
625 | while (pg) { |
626 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | |
627 | pg->index = 0; | |
628 | pg = pg->next; | |
bac429f0 SR |
629 | } |
630 | ||
cafb168a | 631 | memset(stat->hash, 0, |
493762fc SR |
632 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); |
633 | } | |
bac429f0 | 634 | |
cafb168a | 635 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) |
493762fc SR |
636 | { |
637 | struct ftrace_profile_page *pg; | |
318e0a73 SR |
638 | int functions; |
639 | int pages; | |
493762fc | 640 | int i; |
bac429f0 | 641 | |
493762fc | 642 | /* If we already allocated, do nothing */ |
cafb168a | 643 | if (stat->pages) |
493762fc | 644 | return 0; |
bac429f0 | 645 | |
cafb168a SR |
646 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); |
647 | if (!stat->pages) | |
493762fc | 648 | return -ENOMEM; |
bac429f0 | 649 | |
318e0a73 SR |
650 | #ifdef CONFIG_DYNAMIC_FTRACE |
651 | functions = ftrace_update_tot_cnt; | |
652 | #else | |
653 | /* | |
654 | * We do not know the number of functions that exist because | |
655 | * dynamic tracing is what counts them. With past experience | |
656 | * we have around 20K functions. That should be more than enough. | |
657 | * It is highly unlikely we will execute every function in | |
658 | * the kernel. | |
659 | */ | |
660 | functions = 20000; | |
661 | #endif | |
662 | ||
cafb168a | 663 | pg = stat->start = stat->pages; |
bac429f0 | 664 | |
318e0a73 SR |
665 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); |
666 | ||
667 | for (i = 0; i < pages; i++) { | |
493762fc | 668 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
493762fc | 669 | if (!pg->next) |
318e0a73 | 670 | goto out_free; |
493762fc SR |
671 | pg = pg->next; |
672 | } | |
673 | ||
674 | return 0; | |
318e0a73 SR |
675 | |
676 | out_free: | |
677 | pg = stat->start; | |
678 | while (pg) { | |
679 | unsigned long tmp = (unsigned long)pg; | |
680 | ||
681 | pg = pg->next; | |
682 | free_page(tmp); | |
683 | } | |
684 | ||
685 | free_page((unsigned long)stat->pages); | |
686 | stat->pages = NULL; | |
687 | stat->start = NULL; | |
688 | ||
689 | return -ENOMEM; | |
bac429f0 SR |
690 | } |
691 | ||
cafb168a | 692 | static int ftrace_profile_init_cpu(int cpu) |
bac429f0 | 693 | { |
cafb168a | 694 | struct ftrace_profile_stat *stat; |
493762fc | 695 | int size; |
bac429f0 | 696 | |
cafb168a SR |
697 | stat = &per_cpu(ftrace_profile_stats, cpu); |
698 | ||
699 | if (stat->hash) { | |
493762fc | 700 | /* If the profile is already created, simply reset it */ |
cafb168a | 701 | ftrace_profile_reset(stat); |
493762fc SR |
702 | return 0; |
703 | } | |
bac429f0 | 704 | |
493762fc SR |
705 | /* |
706 | * We are profiling all functions, but usually only a few thousand | |
707 | * functions are hit. We'll make a hash of 1024 items. | |
708 | */ | |
709 | size = FTRACE_PROFILE_HASH_SIZE; | |
bac429f0 | 710 | |
cafb168a | 711 | stat->hash = kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL); |
493762fc | 712 | |
cafb168a | 713 | if (!stat->hash) |
493762fc SR |
714 | return -ENOMEM; |
715 | ||
cafb168a SR |
716 | if (!ftrace_profile_bits) { |
717 | size--; | |
493762fc | 718 | |
cafb168a SR |
719 | for (; size; size >>= 1) |
720 | ftrace_profile_bits++; | |
721 | } | |
493762fc | 722 | |
318e0a73 | 723 | /* Preallocate the function profiling pages */ |
cafb168a SR |
724 | if (ftrace_profile_pages_init(stat) < 0) { |
725 | kfree(stat->hash); | |
726 | stat->hash = NULL; | |
493762fc SR |
727 | return -ENOMEM; |
728 | } | |
729 | ||
730 | return 0; | |
bac429f0 SR |
731 | } |
732 | ||
cafb168a SR |
733 | static int ftrace_profile_init(void) |
734 | { | |
735 | int cpu; | |
736 | int ret = 0; | |
737 | ||
738 | for_each_online_cpu(cpu) { | |
739 | ret = ftrace_profile_init_cpu(cpu); | |
740 | if (ret) | |
741 | break; | |
742 | } | |
743 | ||
744 | return ret; | |
745 | } | |
746 | ||
493762fc | 747 | /* interrupts must be disabled */ |
cafb168a SR |
748 | static struct ftrace_profile * |
749 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) | |
bac429f0 | 750 | { |
493762fc | 751 | struct ftrace_profile *rec; |
bac429f0 SR |
752 | struct hlist_head *hhd; |
753 | struct hlist_node *n; | |
bac429f0 SR |
754 | unsigned long key; |
755 | ||
bac429f0 | 756 | key = hash_long(ip, ftrace_profile_bits); |
cafb168a | 757 | hhd = &stat->hash[key]; |
bac429f0 SR |
758 | |
759 | if (hlist_empty(hhd)) | |
760 | return NULL; | |
761 | ||
bac429f0 SR |
762 | hlist_for_each_entry_rcu(rec, n, hhd, node) { |
763 | if (rec->ip == ip) | |
493762fc SR |
764 | return rec; |
765 | } | |
766 | ||
767 | return NULL; | |
768 | } | |
769 | ||
cafb168a SR |
770 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, |
771 | struct ftrace_profile *rec) | |
493762fc SR |
772 | { |
773 | unsigned long key; | |
774 | ||
775 | key = hash_long(rec->ip, ftrace_profile_bits); | |
cafb168a | 776 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); |
493762fc SR |
777 | } |
778 | ||
318e0a73 SR |
779 | /* |
780 | * The memory is already allocated, this simply finds a new record to use. | |
781 | */ | |
493762fc | 782 | static struct ftrace_profile * |
318e0a73 | 783 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) |
493762fc SR |
784 | { |
785 | struct ftrace_profile *rec = NULL; | |
786 | ||
318e0a73 | 787 | /* prevent recursion (from NMIs) */ |
cafb168a | 788 | if (atomic_inc_return(&stat->disabled) != 1) |
493762fc SR |
789 | goto out; |
790 | ||
493762fc | 791 | /* |
318e0a73 SR |
792 | * Try to find the function again since an NMI |
793 | * could have added it | |
493762fc | 794 | */ |
cafb168a | 795 | rec = ftrace_find_profiled_func(stat, ip); |
493762fc | 796 | if (rec) |
cafb168a | 797 | goto out; |
493762fc | 798 | |
cafb168a SR |
799 | if (stat->pages->index == PROFILES_PER_PAGE) { |
800 | if (!stat->pages->next) | |
801 | goto out; | |
802 | stat->pages = stat->pages->next; | |
bac429f0 | 803 | } |
493762fc | 804 | |
cafb168a | 805 | rec = &stat->pages->records[stat->pages->index++]; |
493762fc | 806 | rec->ip = ip; |
cafb168a | 807 | ftrace_add_profile(stat, rec); |
493762fc | 808 | |
bac429f0 | 809 | out: |
cafb168a | 810 | atomic_dec(&stat->disabled); |
bac429f0 SR |
811 | |
812 | return rec; | |
813 | } | |
814 | ||
815 | static void | |
2f5f6ad9 | 816 | function_profile_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 817 | struct ftrace_ops *ops, struct pt_regs *regs) |
bac429f0 | 818 | { |
cafb168a | 819 | struct ftrace_profile_stat *stat; |
493762fc | 820 | struct ftrace_profile *rec; |
bac429f0 SR |
821 | unsigned long flags; |
822 | ||
823 | if (!ftrace_profile_enabled) | |
824 | return; | |
825 | ||
826 | local_irq_save(flags); | |
cafb168a SR |
827 | |
828 | stat = &__get_cpu_var(ftrace_profile_stats); | |
0f6ce3de | 829 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
830 | goto out; |
831 | ||
832 | rec = ftrace_find_profiled_func(stat, ip); | |
493762fc | 833 | if (!rec) { |
318e0a73 | 834 | rec = ftrace_profile_alloc(stat, ip); |
493762fc SR |
835 | if (!rec) |
836 | goto out; | |
837 | } | |
bac429f0 SR |
838 | |
839 | rec->counter++; | |
840 | out: | |
841 | local_irq_restore(flags); | |
842 | } | |
843 | ||
0706f1c4 SR |
844 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
845 | static int profile_graph_entry(struct ftrace_graph_ent *trace) | |
846 | { | |
a1e2e31d | 847 | function_profile_call(trace->func, 0, NULL, NULL); |
0706f1c4 SR |
848 | return 1; |
849 | } | |
850 | ||
851 | static void profile_graph_return(struct ftrace_graph_ret *trace) | |
852 | { | |
cafb168a | 853 | struct ftrace_profile_stat *stat; |
a2a16d6a | 854 | unsigned long long calltime; |
0706f1c4 | 855 | struct ftrace_profile *rec; |
cafb168a | 856 | unsigned long flags; |
0706f1c4 SR |
857 | |
858 | local_irq_save(flags); | |
cafb168a | 859 | stat = &__get_cpu_var(ftrace_profile_stats); |
0f6ce3de | 860 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
861 | goto out; |
862 | ||
37e44bc5 SR |
863 | /* If the calltime was zero'd ignore it */ |
864 | if (!trace->calltime) | |
865 | goto out; | |
866 | ||
a2a16d6a SR |
867 | calltime = trace->rettime - trace->calltime; |
868 | ||
869 | if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) { | |
870 | int index; | |
871 | ||
872 | index = trace->depth; | |
873 | ||
874 | /* Append this call time to the parent time to subtract */ | |
875 | if (index) | |
876 | current->ret_stack[index - 1].subtime += calltime; | |
877 | ||
878 | if (current->ret_stack[index].subtime < calltime) | |
879 | calltime -= current->ret_stack[index].subtime; | |
880 | else | |
881 | calltime = 0; | |
882 | } | |
883 | ||
cafb168a | 884 | rec = ftrace_find_profiled_func(stat, trace->func); |
e330b3bc | 885 | if (rec) { |
a2a16d6a | 886 | rec->time += calltime; |
e330b3bc CD |
887 | rec->time_squared += calltime * calltime; |
888 | } | |
a2a16d6a | 889 | |
cafb168a | 890 | out: |
0706f1c4 SR |
891 | local_irq_restore(flags); |
892 | } | |
893 | ||
894 | static int register_ftrace_profiler(void) | |
895 | { | |
896 | return register_ftrace_graph(&profile_graph_return, | |
897 | &profile_graph_entry); | |
898 | } | |
899 | ||
900 | static void unregister_ftrace_profiler(void) | |
901 | { | |
902 | unregister_ftrace_graph(); | |
903 | } | |
904 | #else | |
bd38c0e6 | 905 | static struct ftrace_ops ftrace_profile_ops __read_mostly = { |
fb9fb015 | 906 | .func = function_profile_call, |
4740974a | 907 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
bac429f0 SR |
908 | }; |
909 | ||
0706f1c4 SR |
910 | static int register_ftrace_profiler(void) |
911 | { | |
912 | return register_ftrace_function(&ftrace_profile_ops); | |
913 | } | |
914 | ||
915 | static void unregister_ftrace_profiler(void) | |
916 | { | |
917 | unregister_ftrace_function(&ftrace_profile_ops); | |
918 | } | |
919 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
920 | ||
bac429f0 SR |
921 | static ssize_t |
922 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | |
923 | size_t cnt, loff_t *ppos) | |
924 | { | |
925 | unsigned long val; | |
bac429f0 SR |
926 | int ret; |
927 | ||
22fe9b54 PH |
928 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
929 | if (ret) | |
bac429f0 SR |
930 | return ret; |
931 | ||
932 | val = !!val; | |
933 | ||
934 | mutex_lock(&ftrace_profile_lock); | |
935 | if (ftrace_profile_enabled ^ val) { | |
936 | if (val) { | |
493762fc SR |
937 | ret = ftrace_profile_init(); |
938 | if (ret < 0) { | |
939 | cnt = ret; | |
940 | goto out; | |
941 | } | |
942 | ||
0706f1c4 SR |
943 | ret = register_ftrace_profiler(); |
944 | if (ret < 0) { | |
945 | cnt = ret; | |
946 | goto out; | |
947 | } | |
bac429f0 SR |
948 | ftrace_profile_enabled = 1; |
949 | } else { | |
950 | ftrace_profile_enabled = 0; | |
0f6ce3de SR |
951 | /* |
952 | * unregister_ftrace_profiler calls stop_machine | |
953 | * so this acts like an synchronize_sched. | |
954 | */ | |
0706f1c4 | 955 | unregister_ftrace_profiler(); |
bac429f0 SR |
956 | } |
957 | } | |
493762fc | 958 | out: |
bac429f0 SR |
959 | mutex_unlock(&ftrace_profile_lock); |
960 | ||
cf8517cf | 961 | *ppos += cnt; |
bac429f0 SR |
962 | |
963 | return cnt; | |
964 | } | |
965 | ||
493762fc SR |
966 | static ssize_t |
967 | ftrace_profile_read(struct file *filp, char __user *ubuf, | |
968 | size_t cnt, loff_t *ppos) | |
969 | { | |
fb9fb015 | 970 | char buf[64]; /* big enough to hold a number */ |
493762fc SR |
971 | int r; |
972 | ||
973 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | |
974 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
975 | } | |
976 | ||
bac429f0 SR |
977 | static const struct file_operations ftrace_profile_fops = { |
978 | .open = tracing_open_generic, | |
979 | .read = ftrace_profile_read, | |
980 | .write = ftrace_profile_write, | |
6038f373 | 981 | .llseek = default_llseek, |
bac429f0 SR |
982 | }; |
983 | ||
cafb168a SR |
984 | /* used to initialize the real stat files */ |
985 | static struct tracer_stat function_stats __initdata = { | |
fb9fb015 SR |
986 | .name = "functions", |
987 | .stat_start = function_stat_start, | |
988 | .stat_next = function_stat_next, | |
989 | .stat_cmp = function_stat_cmp, | |
990 | .stat_headers = function_stat_headers, | |
991 | .stat_show = function_stat_show | |
cafb168a SR |
992 | }; |
993 | ||
6ab5d668 | 994 | static __init void ftrace_profile_debugfs(struct dentry *d_tracer) |
bac429f0 | 995 | { |
cafb168a | 996 | struct ftrace_profile_stat *stat; |
bac429f0 | 997 | struct dentry *entry; |
cafb168a | 998 | char *name; |
bac429f0 | 999 | int ret; |
cafb168a SR |
1000 | int cpu; |
1001 | ||
1002 | for_each_possible_cpu(cpu) { | |
1003 | stat = &per_cpu(ftrace_profile_stats, cpu); | |
1004 | ||
1005 | /* allocate enough for function name + cpu number */ | |
1006 | name = kmalloc(32, GFP_KERNEL); | |
1007 | if (!name) { | |
1008 | /* | |
1009 | * The files created are permanent, if something happens | |
1010 | * we still do not free memory. | |
1011 | */ | |
cafb168a SR |
1012 | WARN(1, |
1013 | "Could not allocate stat file for cpu %d\n", | |
1014 | cpu); | |
1015 | return; | |
1016 | } | |
1017 | stat->stat = function_stats; | |
1018 | snprintf(name, 32, "function%d", cpu); | |
1019 | stat->stat.name = name; | |
1020 | ret = register_stat_tracer(&stat->stat); | |
1021 | if (ret) { | |
1022 | WARN(1, | |
1023 | "Could not register function stat for cpu %d\n", | |
1024 | cpu); | |
1025 | kfree(name); | |
1026 | return; | |
1027 | } | |
bac429f0 SR |
1028 | } |
1029 | ||
1030 | entry = debugfs_create_file("function_profile_enabled", 0644, | |
1031 | d_tracer, NULL, &ftrace_profile_fops); | |
1032 | if (!entry) | |
1033 | pr_warning("Could not create debugfs " | |
1034 | "'function_profile_enabled' entry\n"); | |
1035 | } | |
1036 | ||
bac429f0 | 1037 | #else /* CONFIG_FUNCTION_PROFILER */ |
6ab5d668 | 1038 | static __init void ftrace_profile_debugfs(struct dentry *d_tracer) |
bac429f0 SR |
1039 | { |
1040 | } | |
bac429f0 SR |
1041 | #endif /* CONFIG_FUNCTION_PROFILER */ |
1042 | ||
493762fc SR |
1043 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; |
1044 | ||
1045 | #ifdef CONFIG_DYNAMIC_FTRACE | |
1046 | ||
1047 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD | |
1048 | # error Dynamic ftrace depends on MCOUNT_RECORD | |
1049 | #endif | |
1050 | ||
1051 | static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly; | |
1052 | ||
1053 | struct ftrace_func_probe { | |
1054 | struct hlist_node node; | |
1055 | struct ftrace_probe_ops *ops; | |
1056 | unsigned long flags; | |
1057 | unsigned long ip; | |
1058 | void *data; | |
1059 | struct rcu_head rcu; | |
1060 | }; | |
1061 | ||
b448c4e3 SR |
1062 | struct ftrace_func_entry { |
1063 | struct hlist_node hlist; | |
1064 | unsigned long ip; | |
1065 | }; | |
1066 | ||
1067 | struct ftrace_hash { | |
1068 | unsigned long size_bits; | |
1069 | struct hlist_head *buckets; | |
1070 | unsigned long count; | |
07fd5515 | 1071 | struct rcu_head rcu; |
b448c4e3 SR |
1072 | }; |
1073 | ||
33dc9b12 SR |
1074 | /* |
1075 | * We make these constant because no one should touch them, | |
1076 | * but they are used as the default "empty hash", to avoid allocating | |
1077 | * it all the time. These are in a read only section such that if | |
1078 | * anyone does try to modify it, it will cause an exception. | |
1079 | */ | |
1080 | static const struct hlist_head empty_buckets[1]; | |
1081 | static const struct ftrace_hash empty_hash = { | |
1082 | .buckets = (struct hlist_head *)empty_buckets, | |
1cf41dd7 | 1083 | }; |
33dc9b12 | 1084 | #define EMPTY_HASH ((struct ftrace_hash *)&empty_hash) |
493762fc | 1085 | |
2b499381 | 1086 | static struct ftrace_ops global_ops = { |
f45948e8 | 1087 | .func = ftrace_stub, |
33dc9b12 SR |
1088 | .notrace_hash = EMPTY_HASH, |
1089 | .filter_hash = EMPTY_HASH, | |
4740974a | 1090 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
f45948e8 SR |
1091 | }; |
1092 | ||
493762fc SR |
1093 | static DEFINE_MUTEX(ftrace_regex_lock); |
1094 | ||
1095 | struct ftrace_page { | |
1096 | struct ftrace_page *next; | |
a7900875 | 1097 | struct dyn_ftrace *records; |
493762fc | 1098 | int index; |
a7900875 | 1099 | int size; |
493762fc SR |
1100 | }; |
1101 | ||
85ae32ae SR |
1102 | static struct ftrace_page *ftrace_new_pgs; |
1103 | ||
a7900875 SR |
1104 | #define ENTRY_SIZE sizeof(struct dyn_ftrace) |
1105 | #define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE) | |
493762fc SR |
1106 | |
1107 | /* estimate from running different kernels */ | |
1108 | #define NR_TO_INIT 10000 | |
1109 | ||
1110 | static struct ftrace_page *ftrace_pages_start; | |
1111 | static struct ftrace_page *ftrace_pages; | |
1112 | ||
06a51d93 SR |
1113 | static bool ftrace_hash_empty(struct ftrace_hash *hash) |
1114 | { | |
1115 | return !hash || !hash->count; | |
1116 | } | |
1117 | ||
b448c4e3 SR |
1118 | static struct ftrace_func_entry * |
1119 | ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
1120 | { | |
1121 | unsigned long key; | |
1122 | struct ftrace_func_entry *entry; | |
1123 | struct hlist_head *hhd; | |
1124 | struct hlist_node *n; | |
1125 | ||
06a51d93 | 1126 | if (ftrace_hash_empty(hash)) |
b448c4e3 SR |
1127 | return NULL; |
1128 | ||
1129 | if (hash->size_bits > 0) | |
1130 | key = hash_long(ip, hash->size_bits); | |
1131 | else | |
1132 | key = 0; | |
1133 | ||
1134 | hhd = &hash->buckets[key]; | |
1135 | ||
1136 | hlist_for_each_entry_rcu(entry, n, hhd, hlist) { | |
1137 | if (entry->ip == ip) | |
1138 | return entry; | |
1139 | } | |
1140 | return NULL; | |
1141 | } | |
1142 | ||
33dc9b12 SR |
1143 | static void __add_hash_entry(struct ftrace_hash *hash, |
1144 | struct ftrace_func_entry *entry) | |
b448c4e3 | 1145 | { |
b448c4e3 SR |
1146 | struct hlist_head *hhd; |
1147 | unsigned long key; | |
1148 | ||
b448c4e3 | 1149 | if (hash->size_bits) |
33dc9b12 | 1150 | key = hash_long(entry->ip, hash->size_bits); |
b448c4e3 SR |
1151 | else |
1152 | key = 0; | |
1153 | ||
b448c4e3 SR |
1154 | hhd = &hash->buckets[key]; |
1155 | hlist_add_head(&entry->hlist, hhd); | |
1156 | hash->count++; | |
33dc9b12 SR |
1157 | } |
1158 | ||
1159 | static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) | |
1160 | { | |
1161 | struct ftrace_func_entry *entry; | |
1162 | ||
1163 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
1164 | if (!entry) | |
1165 | return -ENOMEM; | |
1166 | ||
1167 | entry->ip = ip; | |
1168 | __add_hash_entry(hash, entry); | |
b448c4e3 SR |
1169 | |
1170 | return 0; | |
1171 | } | |
1172 | ||
1173 | static void | |
33dc9b12 | 1174 | free_hash_entry(struct ftrace_hash *hash, |
b448c4e3 SR |
1175 | struct ftrace_func_entry *entry) |
1176 | { | |
1177 | hlist_del(&entry->hlist); | |
1178 | kfree(entry); | |
1179 | hash->count--; | |
1180 | } | |
1181 | ||
33dc9b12 SR |
1182 | static void |
1183 | remove_hash_entry(struct ftrace_hash *hash, | |
1184 | struct ftrace_func_entry *entry) | |
1185 | { | |
1186 | hlist_del(&entry->hlist); | |
1187 | hash->count--; | |
1188 | } | |
1189 | ||
b448c4e3 SR |
1190 | static void ftrace_hash_clear(struct ftrace_hash *hash) |
1191 | { | |
1192 | struct hlist_head *hhd; | |
1193 | struct hlist_node *tp, *tn; | |
1194 | struct ftrace_func_entry *entry; | |
1195 | int size = 1 << hash->size_bits; | |
1196 | int i; | |
1197 | ||
33dc9b12 SR |
1198 | if (!hash->count) |
1199 | return; | |
1200 | ||
b448c4e3 SR |
1201 | for (i = 0; i < size; i++) { |
1202 | hhd = &hash->buckets[i]; | |
1203 | hlist_for_each_entry_safe(entry, tp, tn, hhd, hlist) | |
33dc9b12 | 1204 | free_hash_entry(hash, entry); |
b448c4e3 SR |
1205 | } |
1206 | FTRACE_WARN_ON(hash->count); | |
1207 | } | |
1208 | ||
33dc9b12 SR |
1209 | static void free_ftrace_hash(struct ftrace_hash *hash) |
1210 | { | |
1211 | if (!hash || hash == EMPTY_HASH) | |
1212 | return; | |
1213 | ftrace_hash_clear(hash); | |
1214 | kfree(hash->buckets); | |
1215 | kfree(hash); | |
1216 | } | |
1217 | ||
07fd5515 SR |
1218 | static void __free_ftrace_hash_rcu(struct rcu_head *rcu) |
1219 | { | |
1220 | struct ftrace_hash *hash; | |
1221 | ||
1222 | hash = container_of(rcu, struct ftrace_hash, rcu); | |
1223 | free_ftrace_hash(hash); | |
1224 | } | |
1225 | ||
1226 | static void free_ftrace_hash_rcu(struct ftrace_hash *hash) | |
1227 | { | |
1228 | if (!hash || hash == EMPTY_HASH) | |
1229 | return; | |
1230 | call_rcu_sched(&hash->rcu, __free_ftrace_hash_rcu); | |
1231 | } | |
1232 | ||
5500fa51 JO |
1233 | void ftrace_free_filter(struct ftrace_ops *ops) |
1234 | { | |
1235 | free_ftrace_hash(ops->filter_hash); | |
1236 | free_ftrace_hash(ops->notrace_hash); | |
1237 | } | |
1238 | ||
33dc9b12 SR |
1239 | static struct ftrace_hash *alloc_ftrace_hash(int size_bits) |
1240 | { | |
1241 | struct ftrace_hash *hash; | |
1242 | int size; | |
1243 | ||
1244 | hash = kzalloc(sizeof(*hash), GFP_KERNEL); | |
1245 | if (!hash) | |
1246 | return NULL; | |
1247 | ||
1248 | size = 1 << size_bits; | |
47b0edcb | 1249 | hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL); |
33dc9b12 SR |
1250 | |
1251 | if (!hash->buckets) { | |
1252 | kfree(hash); | |
1253 | return NULL; | |
1254 | } | |
1255 | ||
1256 | hash->size_bits = size_bits; | |
1257 | ||
1258 | return hash; | |
1259 | } | |
1260 | ||
1261 | static struct ftrace_hash * | |
1262 | alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) | |
1263 | { | |
1264 | struct ftrace_func_entry *entry; | |
1265 | struct ftrace_hash *new_hash; | |
1266 | struct hlist_node *tp; | |
1267 | int size; | |
1268 | int ret; | |
1269 | int i; | |
1270 | ||
1271 | new_hash = alloc_ftrace_hash(size_bits); | |
1272 | if (!new_hash) | |
1273 | return NULL; | |
1274 | ||
1275 | /* Empty hash? */ | |
06a51d93 | 1276 | if (ftrace_hash_empty(hash)) |
33dc9b12 SR |
1277 | return new_hash; |
1278 | ||
1279 | size = 1 << hash->size_bits; | |
1280 | for (i = 0; i < size; i++) { | |
1281 | hlist_for_each_entry(entry, tp, &hash->buckets[i], hlist) { | |
1282 | ret = add_hash_entry(new_hash, entry->ip); | |
1283 | if (ret < 0) | |
1284 | goto free_hash; | |
1285 | } | |
1286 | } | |
1287 | ||
1288 | FTRACE_WARN_ON(new_hash->count != hash->count); | |
1289 | ||
1290 | return new_hash; | |
1291 | ||
1292 | free_hash: | |
1293 | free_ftrace_hash(new_hash); | |
1294 | return NULL; | |
1295 | } | |
1296 | ||
41fb61c2 SR |
1297 | static void |
1298 | ftrace_hash_rec_disable(struct ftrace_ops *ops, int filter_hash); | |
1299 | static void | |
1300 | ftrace_hash_rec_enable(struct ftrace_ops *ops, int filter_hash); | |
1301 | ||
33dc9b12 | 1302 | static int |
41fb61c2 SR |
1303 | ftrace_hash_move(struct ftrace_ops *ops, int enable, |
1304 | struct ftrace_hash **dst, struct ftrace_hash *src) | |
33dc9b12 SR |
1305 | { |
1306 | struct ftrace_func_entry *entry; | |
1307 | struct hlist_node *tp, *tn; | |
1308 | struct hlist_head *hhd; | |
07fd5515 SR |
1309 | struct ftrace_hash *old_hash; |
1310 | struct ftrace_hash *new_hash; | |
33dc9b12 SR |
1311 | unsigned long key; |
1312 | int size = src->count; | |
1313 | int bits = 0; | |
41fb61c2 | 1314 | int ret; |
33dc9b12 SR |
1315 | int i; |
1316 | ||
41fb61c2 SR |
1317 | /* |
1318 | * Remove the current set, update the hash and add | |
1319 | * them back. | |
1320 | */ | |
1321 | ftrace_hash_rec_disable(ops, enable); | |
1322 | ||
33dc9b12 SR |
1323 | /* |
1324 | * If the new source is empty, just free dst and assign it | |
1325 | * the empty_hash. | |
1326 | */ | |
1327 | if (!src->count) { | |
07fd5515 SR |
1328 | free_ftrace_hash_rcu(*dst); |
1329 | rcu_assign_pointer(*dst, EMPTY_HASH); | |
d4d34b98 SR |
1330 | /* still need to update the function records */ |
1331 | ret = 0; | |
1332 | goto out; | |
33dc9b12 SR |
1333 | } |
1334 | ||
33dc9b12 SR |
1335 | /* |
1336 | * Make the hash size about 1/2 the # found | |
1337 | */ | |
1338 | for (size /= 2; size; size >>= 1) | |
1339 | bits++; | |
1340 | ||
1341 | /* Don't allocate too much */ | |
1342 | if (bits > FTRACE_HASH_MAX_BITS) | |
1343 | bits = FTRACE_HASH_MAX_BITS; | |
1344 | ||
41fb61c2 | 1345 | ret = -ENOMEM; |
07fd5515 SR |
1346 | new_hash = alloc_ftrace_hash(bits); |
1347 | if (!new_hash) | |
41fb61c2 | 1348 | goto out; |
33dc9b12 SR |
1349 | |
1350 | size = 1 << src->size_bits; | |
1351 | for (i = 0; i < size; i++) { | |
1352 | hhd = &src->buckets[i]; | |
1353 | hlist_for_each_entry_safe(entry, tp, tn, hhd, hlist) { | |
1354 | if (bits > 0) | |
1355 | key = hash_long(entry->ip, bits); | |
1356 | else | |
1357 | key = 0; | |
1358 | remove_hash_entry(src, entry); | |
07fd5515 | 1359 | __add_hash_entry(new_hash, entry); |
33dc9b12 SR |
1360 | } |
1361 | } | |
1362 | ||
07fd5515 SR |
1363 | old_hash = *dst; |
1364 | rcu_assign_pointer(*dst, new_hash); | |
1365 | free_ftrace_hash_rcu(old_hash); | |
1366 | ||
41fb61c2 SR |
1367 | ret = 0; |
1368 | out: | |
1369 | /* | |
1370 | * Enable regardless of ret: | |
1371 | * On success, we enable the new hash. | |
1372 | * On failure, we re-enable the original hash. | |
1373 | */ | |
1374 | ftrace_hash_rec_enable(ops, enable); | |
1375 | ||
1376 | return ret; | |
33dc9b12 SR |
1377 | } |
1378 | ||
b848914c SR |
1379 | /* |
1380 | * Test the hashes for this ops to see if we want to call | |
1381 | * the ops->func or not. | |
1382 | * | |
1383 | * It's a match if the ip is in the ops->filter_hash or | |
1384 | * the filter_hash does not exist or is empty, | |
1385 | * AND | |
1386 | * the ip is not in the ops->notrace_hash. | |
cdbe61bf SR |
1387 | * |
1388 | * This needs to be called with preemption disabled as | |
1389 | * the hashes are freed with call_rcu_sched(). | |
b848914c SR |
1390 | */ |
1391 | static int | |
1392 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip) | |
1393 | { | |
1394 | struct ftrace_hash *filter_hash; | |
1395 | struct ftrace_hash *notrace_hash; | |
1396 | int ret; | |
1397 | ||
b848914c SR |
1398 | filter_hash = rcu_dereference_raw(ops->filter_hash); |
1399 | notrace_hash = rcu_dereference_raw(ops->notrace_hash); | |
1400 | ||
06a51d93 | 1401 | if ((ftrace_hash_empty(filter_hash) || |
b848914c | 1402 | ftrace_lookup_ip(filter_hash, ip)) && |
06a51d93 | 1403 | (ftrace_hash_empty(notrace_hash) || |
b848914c SR |
1404 | !ftrace_lookup_ip(notrace_hash, ip))) |
1405 | ret = 1; | |
1406 | else | |
1407 | ret = 0; | |
b848914c SR |
1408 | |
1409 | return ret; | |
1410 | } | |
1411 | ||
493762fc SR |
1412 | /* |
1413 | * This is a double for. Do not use 'break' to break out of the loop, | |
1414 | * you must use a goto. | |
1415 | */ | |
1416 | #define do_for_each_ftrace_rec(pg, rec) \ | |
1417 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
1418 | int _____i; \ | |
1419 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
1420 | rec = &pg->records[_____i]; | |
1421 | ||
1422 | #define while_for_each_ftrace_rec() \ | |
1423 | } \ | |
1424 | } | |
1425 | ||
5855fead SR |
1426 | |
1427 | static int ftrace_cmp_recs(const void *a, const void *b) | |
1428 | { | |
a650e02a SR |
1429 | const struct dyn_ftrace *key = a; |
1430 | const struct dyn_ftrace *rec = b; | |
5855fead | 1431 | |
a650e02a | 1432 | if (key->flags < rec->ip) |
5855fead | 1433 | return -1; |
a650e02a SR |
1434 | if (key->ip >= rec->ip + MCOUNT_INSN_SIZE) |
1435 | return 1; | |
5855fead SR |
1436 | return 0; |
1437 | } | |
1438 | ||
f0cf973a | 1439 | static unsigned long ftrace_location_range(unsigned long start, unsigned long end) |
c88fd863 SR |
1440 | { |
1441 | struct ftrace_page *pg; | |
1442 | struct dyn_ftrace *rec; | |
5855fead | 1443 | struct dyn_ftrace key; |
c88fd863 | 1444 | |
a650e02a SR |
1445 | key.ip = start; |
1446 | key.flags = end; /* overload flags, as it is unsigned long */ | |
5855fead SR |
1447 | |
1448 | for (pg = ftrace_pages_start; pg; pg = pg->next) { | |
a650e02a SR |
1449 | if (end < pg->records[0].ip || |
1450 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) | |
9644302e | 1451 | continue; |
5855fead SR |
1452 | rec = bsearch(&key, pg->records, pg->index, |
1453 | sizeof(struct dyn_ftrace), | |
1454 | ftrace_cmp_recs); | |
1455 | if (rec) | |
f0cf973a | 1456 | return rec->ip; |
5855fead | 1457 | } |
c88fd863 SR |
1458 | |
1459 | return 0; | |
1460 | } | |
1461 | ||
a650e02a SR |
1462 | /** |
1463 | * ftrace_location - return true if the ip giving is a traced location | |
1464 | * @ip: the instruction pointer to check | |
1465 | * | |
f0cf973a | 1466 | * Returns rec->ip if @ip given is a pointer to a ftrace location. |
a650e02a SR |
1467 | * That is, the instruction that is either a NOP or call to |
1468 | * the function tracer. It checks the ftrace internal tables to | |
1469 | * determine if the address belongs or not. | |
1470 | */ | |
f0cf973a | 1471 | unsigned long ftrace_location(unsigned long ip) |
a650e02a SR |
1472 | { |
1473 | return ftrace_location_range(ip, ip); | |
1474 | } | |
1475 | ||
1476 | /** | |
1477 | * ftrace_text_reserved - return true if range contains an ftrace location | |
1478 | * @start: start of range to search | |
1479 | * @end: end of range to search (inclusive). @end points to the last byte to check. | |
1480 | * | |
1481 | * Returns 1 if @start and @end contains a ftrace location. | |
1482 | * That is, the instruction that is either a NOP or call to | |
1483 | * the function tracer. It checks the ftrace internal tables to | |
1484 | * determine if the address belongs or not. | |
1485 | */ | |
1486 | int ftrace_text_reserved(void *start, void *end) | |
1487 | { | |
f0cf973a SR |
1488 | unsigned long ret; |
1489 | ||
1490 | ret = ftrace_location_range((unsigned long)start, | |
1491 | (unsigned long)end); | |
1492 | ||
1493 | return (int)!!ret; | |
a650e02a SR |
1494 | } |
1495 | ||
ed926f9b SR |
1496 | static void __ftrace_hash_rec_update(struct ftrace_ops *ops, |
1497 | int filter_hash, | |
1498 | bool inc) | |
1499 | { | |
1500 | struct ftrace_hash *hash; | |
1501 | struct ftrace_hash *other_hash; | |
1502 | struct ftrace_page *pg; | |
1503 | struct dyn_ftrace *rec; | |
1504 | int count = 0; | |
1505 | int all = 0; | |
1506 | ||
1507 | /* Only update if the ops has been registered */ | |
1508 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
1509 | return; | |
1510 | ||
1511 | /* | |
1512 | * In the filter_hash case: | |
1513 | * If the count is zero, we update all records. | |
1514 | * Otherwise we just update the items in the hash. | |
1515 | * | |
1516 | * In the notrace_hash case: | |
1517 | * We enable the update in the hash. | |
1518 | * As disabling notrace means enabling the tracing, | |
1519 | * and enabling notrace means disabling, the inc variable | |
1520 | * gets inversed. | |
1521 | */ | |
1522 | if (filter_hash) { | |
1523 | hash = ops->filter_hash; | |
1524 | other_hash = ops->notrace_hash; | |
06a51d93 | 1525 | if (ftrace_hash_empty(hash)) |
ed926f9b SR |
1526 | all = 1; |
1527 | } else { | |
1528 | inc = !inc; | |
1529 | hash = ops->notrace_hash; | |
1530 | other_hash = ops->filter_hash; | |
1531 | /* | |
1532 | * If the notrace hash has no items, | |
1533 | * then there's nothing to do. | |
1534 | */ | |
06a51d93 | 1535 | if (ftrace_hash_empty(hash)) |
ed926f9b SR |
1536 | return; |
1537 | } | |
1538 | ||
1539 | do_for_each_ftrace_rec(pg, rec) { | |
1540 | int in_other_hash = 0; | |
1541 | int in_hash = 0; | |
1542 | int match = 0; | |
1543 | ||
1544 | if (all) { | |
1545 | /* | |
1546 | * Only the filter_hash affects all records. | |
1547 | * Update if the record is not in the notrace hash. | |
1548 | */ | |
b848914c | 1549 | if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip)) |
ed926f9b SR |
1550 | match = 1; |
1551 | } else { | |
06a51d93 SR |
1552 | in_hash = !!ftrace_lookup_ip(hash, rec->ip); |
1553 | in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip); | |
ed926f9b SR |
1554 | |
1555 | /* | |
1556 | * | |
1557 | */ | |
1558 | if (filter_hash && in_hash && !in_other_hash) | |
1559 | match = 1; | |
1560 | else if (!filter_hash && in_hash && | |
06a51d93 | 1561 | (in_other_hash || ftrace_hash_empty(other_hash))) |
ed926f9b SR |
1562 | match = 1; |
1563 | } | |
1564 | if (!match) | |
1565 | continue; | |
1566 | ||
1567 | if (inc) { | |
1568 | rec->flags++; | |
1569 | if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == FTRACE_REF_MAX)) | |
1570 | return; | |
08f6fba5 SR |
1571 | /* |
1572 | * If any ops wants regs saved for this function | |
1573 | * then all ops will get saved regs. | |
1574 | */ | |
1575 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) | |
1576 | rec->flags |= FTRACE_FL_REGS; | |
ed926f9b SR |
1577 | } else { |
1578 | if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == 0)) | |
1579 | return; | |
1580 | rec->flags--; | |
1581 | } | |
1582 | count++; | |
1583 | /* Shortcut, if we handled all records, we are done. */ | |
1584 | if (!all && count == hash->count) | |
1585 | return; | |
1586 | } while_for_each_ftrace_rec(); | |
1587 | } | |
1588 | ||
1589 | static void ftrace_hash_rec_disable(struct ftrace_ops *ops, | |
1590 | int filter_hash) | |
1591 | { | |
1592 | __ftrace_hash_rec_update(ops, filter_hash, 0); | |
1593 | } | |
1594 | ||
1595 | static void ftrace_hash_rec_enable(struct ftrace_ops *ops, | |
1596 | int filter_hash) | |
1597 | { | |
1598 | __ftrace_hash_rec_update(ops, filter_hash, 1); | |
1599 | } | |
1600 | ||
b17e8a37 SR |
1601 | static void print_ip_ins(const char *fmt, unsigned char *p) |
1602 | { | |
1603 | int i; | |
1604 | ||
1605 | printk(KERN_CONT "%s", fmt); | |
1606 | ||
1607 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
1608 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
1609 | } | |
1610 | ||
c88fd863 SR |
1611 | /** |
1612 | * ftrace_bug - report and shutdown function tracer | |
1613 | * @failed: The failed type (EFAULT, EINVAL, EPERM) | |
1614 | * @ip: The address that failed | |
1615 | * | |
1616 | * The arch code that enables or disables the function tracing | |
1617 | * can call ftrace_bug() when it has detected a problem in | |
1618 | * modifying the code. @failed should be one of either: | |
1619 | * EFAULT - if the problem happens on reading the @ip address | |
1620 | * EINVAL - if what is read at @ip is not what was expected | |
1621 | * EPERM - if the problem happens on writting to the @ip address | |
1622 | */ | |
1623 | void ftrace_bug(int failed, unsigned long ip) | |
b17e8a37 SR |
1624 | { |
1625 | switch (failed) { | |
1626 | case -EFAULT: | |
1627 | FTRACE_WARN_ON_ONCE(1); | |
1628 | pr_info("ftrace faulted on modifying "); | |
1629 | print_ip_sym(ip); | |
1630 | break; | |
1631 | case -EINVAL: | |
1632 | FTRACE_WARN_ON_ONCE(1); | |
1633 | pr_info("ftrace failed to modify "); | |
1634 | print_ip_sym(ip); | |
b17e8a37 | 1635 | print_ip_ins(" actual: ", (unsigned char *)ip); |
b17e8a37 SR |
1636 | printk(KERN_CONT "\n"); |
1637 | break; | |
1638 | case -EPERM: | |
1639 | FTRACE_WARN_ON_ONCE(1); | |
1640 | pr_info("ftrace faulted on writing "); | |
1641 | print_ip_sym(ip); | |
1642 | break; | |
1643 | default: | |
1644 | FTRACE_WARN_ON_ONCE(1); | |
1645 | pr_info("ftrace faulted on unknown error "); | |
1646 | print_ip_sym(ip); | |
1647 | } | |
1648 | } | |
1649 | ||
c88fd863 | 1650 | static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update) |
5072c59f | 1651 | { |
64fbcd16 | 1652 | unsigned long flag = 0UL; |
e7d3737e | 1653 | |
982c350b | 1654 | /* |
30fb6aa7 | 1655 | * If we are updating calls: |
982c350b | 1656 | * |
ed926f9b SR |
1657 | * If the record has a ref count, then we need to enable it |
1658 | * because someone is using it. | |
982c350b | 1659 | * |
ed926f9b SR |
1660 | * Otherwise we make sure its disabled. |
1661 | * | |
30fb6aa7 | 1662 | * If we are disabling calls, then disable all records that |
ed926f9b | 1663 | * are enabled. |
982c350b | 1664 | */ |
c88fd863 | 1665 | if (enable && (rec->flags & ~FTRACE_FL_MASK)) |
ed926f9b | 1666 | flag = FTRACE_FL_ENABLED; |
982c350b | 1667 | |
08f6fba5 SR |
1668 | /* |
1669 | * If enabling and the REGS flag does not match the REGS_EN, then | |
1670 | * do not ignore this record. Set flags to fail the compare against | |
1671 | * ENABLED. | |
1672 | */ | |
1673 | if (flag && | |
1674 | (!(rec->flags & FTRACE_FL_REGS) != !(rec->flags & FTRACE_FL_REGS_EN))) | |
1675 | flag |= FTRACE_FL_REGS; | |
1676 | ||
64fbcd16 XG |
1677 | /* If the state of this record hasn't changed, then do nothing */ |
1678 | if ((rec->flags & FTRACE_FL_ENABLED) == flag) | |
c88fd863 | 1679 | return FTRACE_UPDATE_IGNORE; |
982c350b | 1680 | |
64fbcd16 | 1681 | if (flag) { |
08f6fba5 SR |
1682 | /* Save off if rec is being enabled (for return value) */ |
1683 | flag ^= rec->flags & FTRACE_FL_ENABLED; | |
1684 | ||
1685 | if (update) { | |
c88fd863 | 1686 | rec->flags |= FTRACE_FL_ENABLED; |
08f6fba5 SR |
1687 | if (flag & FTRACE_FL_REGS) { |
1688 | if (rec->flags & FTRACE_FL_REGS) | |
1689 | rec->flags |= FTRACE_FL_REGS_EN; | |
1690 | else | |
1691 | rec->flags &= ~FTRACE_FL_REGS_EN; | |
1692 | } | |
1693 | } | |
1694 | ||
1695 | /* | |
1696 | * If this record is being updated from a nop, then | |
1697 | * return UPDATE_MAKE_CALL. | |
1698 | * Otherwise, if the EN flag is set, then return | |
1699 | * UPDATE_MODIFY_CALL_REGS to tell the caller to convert | |
1700 | * from the non-save regs, to a save regs function. | |
1701 | * Otherwise, | |
1702 | * return UPDATE_MODIFY_CALL to tell the caller to convert | |
1703 | * from the save regs, to a non-save regs function. | |
1704 | */ | |
1705 | if (flag & FTRACE_FL_ENABLED) | |
1706 | return FTRACE_UPDATE_MAKE_CALL; | |
1707 | else if (rec->flags & FTRACE_FL_REGS_EN) | |
1708 | return FTRACE_UPDATE_MODIFY_CALL_REGS; | |
1709 | else | |
1710 | return FTRACE_UPDATE_MODIFY_CALL; | |
c88fd863 SR |
1711 | } |
1712 | ||
08f6fba5 SR |
1713 | if (update) { |
1714 | /* If there's no more users, clear all flags */ | |
1715 | if (!(rec->flags & ~FTRACE_FL_MASK)) | |
1716 | rec->flags = 0; | |
1717 | else | |
1718 | /* Just disable the record (keep REGS state) */ | |
1719 | rec->flags &= ~FTRACE_FL_ENABLED; | |
1720 | } | |
c88fd863 SR |
1721 | |
1722 | return FTRACE_UPDATE_MAKE_NOP; | |
1723 | } | |
1724 | ||
1725 | /** | |
1726 | * ftrace_update_record, set a record that now is tracing or not | |
1727 | * @rec: the record to update | |
1728 | * @enable: set to 1 if the record is tracing, zero to force disable | |
1729 | * | |
1730 | * The records that represent all functions that can be traced need | |
1731 | * to be updated when tracing has been enabled. | |
1732 | */ | |
1733 | int ftrace_update_record(struct dyn_ftrace *rec, int enable) | |
1734 | { | |
1735 | return ftrace_check_record(rec, enable, 1); | |
1736 | } | |
1737 | ||
1738 | /** | |
1739 | * ftrace_test_record, check if the record has been enabled or not | |
1740 | * @rec: the record to test | |
1741 | * @enable: set to 1 to check if enabled, 0 if it is disabled | |
1742 | * | |
1743 | * The arch code may need to test if a record is already set to | |
1744 | * tracing to determine how to modify the function code that it | |
1745 | * represents. | |
1746 | */ | |
1747 | int ftrace_test_record(struct dyn_ftrace *rec, int enable) | |
1748 | { | |
1749 | return ftrace_check_record(rec, enable, 0); | |
1750 | } | |
1751 | ||
1752 | static int | |
1753 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) | |
1754 | { | |
08f6fba5 | 1755 | unsigned long ftrace_old_addr; |
c88fd863 SR |
1756 | unsigned long ftrace_addr; |
1757 | int ret; | |
1758 | ||
c88fd863 SR |
1759 | ret = ftrace_update_record(rec, enable); |
1760 | ||
08f6fba5 SR |
1761 | if (rec->flags & FTRACE_FL_REGS) |
1762 | ftrace_addr = (unsigned long)FTRACE_REGS_ADDR; | |
1763 | else | |
1764 | ftrace_addr = (unsigned long)FTRACE_ADDR; | |
1765 | ||
c88fd863 SR |
1766 | switch (ret) { |
1767 | case FTRACE_UPDATE_IGNORE: | |
1768 | return 0; | |
1769 | ||
1770 | case FTRACE_UPDATE_MAKE_CALL: | |
64fbcd16 | 1771 | return ftrace_make_call(rec, ftrace_addr); |
c88fd863 SR |
1772 | |
1773 | case FTRACE_UPDATE_MAKE_NOP: | |
1774 | return ftrace_make_nop(NULL, rec, ftrace_addr); | |
08f6fba5 SR |
1775 | |
1776 | case FTRACE_UPDATE_MODIFY_CALL_REGS: | |
1777 | case FTRACE_UPDATE_MODIFY_CALL: | |
1778 | if (rec->flags & FTRACE_FL_REGS) | |
1779 | ftrace_old_addr = (unsigned long)FTRACE_ADDR; | |
1780 | else | |
1781 | ftrace_old_addr = (unsigned long)FTRACE_REGS_ADDR; | |
1782 | ||
1783 | return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr); | |
5072c59f SR |
1784 | } |
1785 | ||
c88fd863 | 1786 | return -1; /* unknow ftrace bug */ |
5072c59f SR |
1787 | } |
1788 | ||
e4f5d544 | 1789 | void __weak ftrace_replace_code(int enable) |
3c1720f0 | 1790 | { |
3c1720f0 SR |
1791 | struct dyn_ftrace *rec; |
1792 | struct ftrace_page *pg; | |
6a24a244 | 1793 | int failed; |
3c1720f0 | 1794 | |
45a4a237 SR |
1795 | if (unlikely(ftrace_disabled)) |
1796 | return; | |
1797 | ||
265c831c | 1798 | do_for_each_ftrace_rec(pg, rec) { |
e4f5d544 | 1799 | failed = __ftrace_replace_code(rec, enable); |
fa9d13cf | 1800 | if (failed) { |
3279ba37 SR |
1801 | ftrace_bug(failed, rec->ip); |
1802 | /* Stop processing */ | |
1803 | return; | |
3c1720f0 | 1804 | } |
265c831c | 1805 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
1806 | } |
1807 | ||
c88fd863 SR |
1808 | struct ftrace_rec_iter { |
1809 | struct ftrace_page *pg; | |
1810 | int index; | |
1811 | }; | |
1812 | ||
1813 | /** | |
1814 | * ftrace_rec_iter_start, start up iterating over traced functions | |
1815 | * | |
1816 | * Returns an iterator handle that is used to iterate over all | |
1817 | * the records that represent address locations where functions | |
1818 | * are traced. | |
1819 | * | |
1820 | * May return NULL if no records are available. | |
1821 | */ | |
1822 | struct ftrace_rec_iter *ftrace_rec_iter_start(void) | |
1823 | { | |
1824 | /* | |
1825 | * We only use a single iterator. | |
1826 | * Protected by the ftrace_lock mutex. | |
1827 | */ | |
1828 | static struct ftrace_rec_iter ftrace_rec_iter; | |
1829 | struct ftrace_rec_iter *iter = &ftrace_rec_iter; | |
1830 | ||
1831 | iter->pg = ftrace_pages_start; | |
1832 | iter->index = 0; | |
1833 | ||
1834 | /* Could have empty pages */ | |
1835 | while (iter->pg && !iter->pg->index) | |
1836 | iter->pg = iter->pg->next; | |
1837 | ||
1838 | if (!iter->pg) | |
1839 | return NULL; | |
1840 | ||
1841 | return iter; | |
1842 | } | |
1843 | ||
1844 | /** | |
1845 | * ftrace_rec_iter_next, get the next record to process. | |
1846 | * @iter: The handle to the iterator. | |
1847 | * | |
1848 | * Returns the next iterator after the given iterator @iter. | |
1849 | */ | |
1850 | struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter) | |
1851 | { | |
1852 | iter->index++; | |
1853 | ||
1854 | if (iter->index >= iter->pg->index) { | |
1855 | iter->pg = iter->pg->next; | |
1856 | iter->index = 0; | |
1857 | ||
1858 | /* Could have empty pages */ | |
1859 | while (iter->pg && !iter->pg->index) | |
1860 | iter->pg = iter->pg->next; | |
1861 | } | |
1862 | ||
1863 | if (!iter->pg) | |
1864 | return NULL; | |
1865 | ||
1866 | return iter; | |
1867 | } | |
1868 | ||
1869 | /** | |
1870 | * ftrace_rec_iter_record, get the record at the iterator location | |
1871 | * @iter: The current iterator location | |
1872 | * | |
1873 | * Returns the record that the current @iter is at. | |
1874 | */ | |
1875 | struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter) | |
1876 | { | |
1877 | return &iter->pg->records[iter->index]; | |
1878 | } | |
1879 | ||
492a7ea5 | 1880 | static int |
31e88909 | 1881 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 SR |
1882 | { |
1883 | unsigned long ip; | |
593eb8a2 | 1884 | int ret; |
3c1720f0 SR |
1885 | |
1886 | ip = rec->ip; | |
1887 | ||
45a4a237 SR |
1888 | if (unlikely(ftrace_disabled)) |
1889 | return 0; | |
1890 | ||
25aac9dc | 1891 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
593eb8a2 | 1892 | if (ret) { |
31e88909 | 1893 | ftrace_bug(ret, ip); |
492a7ea5 | 1894 | return 0; |
37ad5084 | 1895 | } |
492a7ea5 | 1896 | return 1; |
3c1720f0 SR |
1897 | } |
1898 | ||
000ab691 SR |
1899 | /* |
1900 | * archs can override this function if they must do something | |
1901 | * before the modifying code is performed. | |
1902 | */ | |
1903 | int __weak ftrace_arch_code_modify_prepare(void) | |
1904 | { | |
1905 | return 0; | |
1906 | } | |
1907 | ||
1908 | /* | |
1909 | * archs can override this function if they must do something | |
1910 | * after the modifying code is performed. | |
1911 | */ | |
1912 | int __weak ftrace_arch_code_modify_post_process(void) | |
1913 | { | |
1914 | return 0; | |
1915 | } | |
1916 | ||
8ed3e2cf | 1917 | void ftrace_modify_all_code(int command) |
3d083395 | 1918 | { |
8ed3e2cf | 1919 | if (command & FTRACE_UPDATE_CALLS) |
d61f82d0 | 1920 | ftrace_replace_code(1); |
8ed3e2cf | 1921 | else if (command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
1922 | ftrace_replace_code(0); |
1923 | ||
8ed3e2cf | 1924 | if (command & FTRACE_UPDATE_TRACE_FUNC) |
d61f82d0 SR |
1925 | ftrace_update_ftrace_func(ftrace_trace_function); |
1926 | ||
8ed3e2cf | 1927 | if (command & FTRACE_START_FUNC_RET) |
5a45cfe1 | 1928 | ftrace_enable_ftrace_graph_caller(); |
8ed3e2cf | 1929 | else if (command & FTRACE_STOP_FUNC_RET) |
5a45cfe1 | 1930 | ftrace_disable_ftrace_graph_caller(); |
8ed3e2cf SR |
1931 | } |
1932 | ||
1933 | static int __ftrace_modify_code(void *data) | |
1934 | { | |
1935 | int *command = data; | |
1936 | ||
1937 | ftrace_modify_all_code(*command); | |
5a45cfe1 | 1938 | |
d61f82d0 | 1939 | return 0; |
3d083395 SR |
1940 | } |
1941 | ||
c88fd863 SR |
1942 | /** |
1943 | * ftrace_run_stop_machine, go back to the stop machine method | |
1944 | * @command: The command to tell ftrace what to do | |
1945 | * | |
1946 | * If an arch needs to fall back to the stop machine method, the | |
1947 | * it can call this function. | |
1948 | */ | |
1949 | void ftrace_run_stop_machine(int command) | |
1950 | { | |
1951 | stop_machine(__ftrace_modify_code, &command, NULL); | |
1952 | } | |
1953 | ||
1954 | /** | |
1955 | * arch_ftrace_update_code, modify the code to trace or not trace | |
1956 | * @command: The command that needs to be done | |
1957 | * | |
1958 | * Archs can override this function if it does not need to | |
1959 | * run stop_machine() to modify code. | |
1960 | */ | |
1961 | void __weak arch_ftrace_update_code(int command) | |
1962 | { | |
1963 | ftrace_run_stop_machine(command); | |
1964 | } | |
1965 | ||
e309b41d | 1966 | static void ftrace_run_update_code(int command) |
3d083395 | 1967 | { |
000ab691 SR |
1968 | int ret; |
1969 | ||
1970 | ret = ftrace_arch_code_modify_prepare(); | |
1971 | FTRACE_WARN_ON(ret); | |
1972 | if (ret) | |
1973 | return; | |
c88fd863 SR |
1974 | /* |
1975 | * Do not call function tracer while we update the code. | |
1976 | * We are in stop machine. | |
1977 | */ | |
1978 | function_trace_stop++; | |
000ab691 | 1979 | |
c88fd863 SR |
1980 | /* |
1981 | * By default we use stop_machine() to modify the code. | |
1982 | * But archs can do what ever they want as long as it | |
1983 | * is safe. The stop_machine() is the safest, but also | |
1984 | * produces the most overhead. | |
1985 | */ | |
1986 | arch_ftrace_update_code(command); | |
1987 | ||
c88fd863 | 1988 | function_trace_stop--; |
000ab691 SR |
1989 | |
1990 | ret = ftrace_arch_code_modify_post_process(); | |
1991 | FTRACE_WARN_ON(ret); | |
3d083395 SR |
1992 | } |
1993 | ||
d61f82d0 | 1994 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 1995 | static int ftrace_start_up; |
b848914c | 1996 | static int global_start_up; |
df4fc315 SR |
1997 | |
1998 | static void ftrace_startup_enable(int command) | |
1999 | { | |
2000 | if (saved_ftrace_func != ftrace_trace_function) { | |
2001 | saved_ftrace_func = ftrace_trace_function; | |
2002 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2003 | } | |
2004 | ||
2005 | if (!command || !ftrace_enabled) | |
2006 | return; | |
2007 | ||
2008 | ftrace_run_update_code(command); | |
2009 | } | |
d61f82d0 | 2010 | |
a1cd6173 | 2011 | static int ftrace_startup(struct ftrace_ops *ops, int command) |
3d083395 | 2012 | { |
b848914c SR |
2013 | bool hash_enable = true; |
2014 | ||
4eebcc81 | 2015 | if (unlikely(ftrace_disabled)) |
a1cd6173 | 2016 | return -ENODEV; |
4eebcc81 | 2017 | |
60a7ecf4 | 2018 | ftrace_start_up++; |
30fb6aa7 | 2019 | command |= FTRACE_UPDATE_CALLS; |
d61f82d0 | 2020 | |
b848914c SR |
2021 | /* ops marked global share the filter hashes */ |
2022 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { | |
2023 | ops = &global_ops; | |
2024 | /* Don't update hash if global is already set */ | |
2025 | if (global_start_up) | |
2026 | hash_enable = false; | |
2027 | global_start_up++; | |
2028 | } | |
2029 | ||
ed926f9b | 2030 | ops->flags |= FTRACE_OPS_FL_ENABLED; |
b848914c | 2031 | if (hash_enable) |
ed926f9b SR |
2032 | ftrace_hash_rec_enable(ops, 1); |
2033 | ||
df4fc315 | 2034 | ftrace_startup_enable(command); |
a1cd6173 SR |
2035 | |
2036 | return 0; | |
3d083395 SR |
2037 | } |
2038 | ||
bd69c30b | 2039 | static void ftrace_shutdown(struct ftrace_ops *ops, int command) |
3d083395 | 2040 | { |
b848914c SR |
2041 | bool hash_disable = true; |
2042 | ||
4eebcc81 SR |
2043 | if (unlikely(ftrace_disabled)) |
2044 | return; | |
2045 | ||
60a7ecf4 | 2046 | ftrace_start_up--; |
9ea1a153 FW |
2047 | /* |
2048 | * Just warn in case of unbalance, no need to kill ftrace, it's not | |
2049 | * critical but the ftrace_call callers may be never nopped again after | |
2050 | * further ftrace uses. | |
2051 | */ | |
2052 | WARN_ON_ONCE(ftrace_start_up < 0); | |
2053 | ||
b848914c SR |
2054 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
2055 | ops = &global_ops; | |
2056 | global_start_up--; | |
2057 | WARN_ON_ONCE(global_start_up < 0); | |
2058 | /* Don't update hash if global still has users */ | |
2059 | if (global_start_up) { | |
2060 | WARN_ON_ONCE(!ftrace_start_up); | |
2061 | hash_disable = false; | |
2062 | } | |
2063 | } | |
2064 | ||
2065 | if (hash_disable) | |
ed926f9b SR |
2066 | ftrace_hash_rec_disable(ops, 1); |
2067 | ||
b848914c | 2068 | if (ops != &global_ops || !global_start_up) |
ed926f9b | 2069 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; |
b848914c | 2070 | |
30fb6aa7 | 2071 | command |= FTRACE_UPDATE_CALLS; |
3d083395 | 2072 | |
d61f82d0 SR |
2073 | if (saved_ftrace_func != ftrace_trace_function) { |
2074 | saved_ftrace_func = ftrace_trace_function; | |
2075 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2076 | } | |
3d083395 | 2077 | |
d61f82d0 | 2078 | if (!command || !ftrace_enabled) |
e6ea44e9 | 2079 | return; |
d61f82d0 SR |
2080 | |
2081 | ftrace_run_update_code(command); | |
3d083395 SR |
2082 | } |
2083 | ||
e309b41d | 2084 | static void ftrace_startup_sysctl(void) |
b0fc494f | 2085 | { |
4eebcc81 SR |
2086 | if (unlikely(ftrace_disabled)) |
2087 | return; | |
2088 | ||
d61f82d0 SR |
2089 | /* Force update next time */ |
2090 | saved_ftrace_func = NULL; | |
60a7ecf4 SR |
2091 | /* ftrace_start_up is true if we want ftrace running */ |
2092 | if (ftrace_start_up) | |
30fb6aa7 | 2093 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); |
b0fc494f SR |
2094 | } |
2095 | ||
e309b41d | 2096 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 2097 | { |
4eebcc81 SR |
2098 | if (unlikely(ftrace_disabled)) |
2099 | return; | |
2100 | ||
60a7ecf4 SR |
2101 | /* ftrace_start_up is true if ftrace is running */ |
2102 | if (ftrace_start_up) | |
79e406d7 | 2103 | ftrace_run_update_code(FTRACE_DISABLE_CALLS); |
b0fc494f SR |
2104 | } |
2105 | ||
3d083395 SR |
2106 | static cycle_t ftrace_update_time; |
2107 | static unsigned long ftrace_update_cnt; | |
2108 | unsigned long ftrace_update_tot_cnt; | |
2109 | ||
f7bc8b61 SR |
2110 | static int ops_traces_mod(struct ftrace_ops *ops) |
2111 | { | |
2112 | struct ftrace_hash *hash; | |
2113 | ||
2114 | hash = ops->filter_hash; | |
06a51d93 | 2115 | return ftrace_hash_empty(hash); |
f7bc8b61 SR |
2116 | } |
2117 | ||
31e88909 | 2118 | static int ftrace_update_code(struct module *mod) |
3d083395 | 2119 | { |
85ae32ae | 2120 | struct ftrace_page *pg; |
e94142a6 | 2121 | struct dyn_ftrace *p; |
f22f9a89 | 2122 | cycle_t start, stop; |
f7bc8b61 | 2123 | unsigned long ref = 0; |
85ae32ae | 2124 | int i; |
f7bc8b61 SR |
2125 | |
2126 | /* | |
2127 | * When adding a module, we need to check if tracers are | |
2128 | * currently enabled and if they are set to trace all functions. | |
2129 | * If they are, we need to enable the module functions as well | |
2130 | * as update the reference counts for those function records. | |
2131 | */ | |
2132 | if (mod) { | |
2133 | struct ftrace_ops *ops; | |
2134 | ||
2135 | for (ops = ftrace_ops_list; | |
2136 | ops != &ftrace_list_end; ops = ops->next) { | |
2137 | if (ops->flags & FTRACE_OPS_FL_ENABLED && | |
2138 | ops_traces_mod(ops)) | |
2139 | ref++; | |
2140 | } | |
2141 | } | |
3d083395 | 2142 | |
750ed1a4 | 2143 | start = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
2144 | ftrace_update_cnt = 0; |
2145 | ||
85ae32ae | 2146 | for (pg = ftrace_new_pgs; pg; pg = pg->next) { |
3d083395 | 2147 | |
85ae32ae SR |
2148 | for (i = 0; i < pg->index; i++) { |
2149 | /* If something went wrong, bail without enabling anything */ | |
2150 | if (unlikely(ftrace_disabled)) | |
2151 | return -1; | |
f22f9a89 | 2152 | |
85ae32ae SR |
2153 | p = &pg->records[i]; |
2154 | p->flags = ref; | |
f22f9a89 | 2155 | |
85ae32ae SR |
2156 | /* |
2157 | * Do the initial record conversion from mcount jump | |
2158 | * to the NOP instructions. | |
2159 | */ | |
2160 | if (!ftrace_code_disable(mod, p)) | |
2161 | break; | |
5cb084bb | 2162 | |
85ae32ae | 2163 | ftrace_update_cnt++; |
5cb084bb | 2164 | |
85ae32ae SR |
2165 | /* |
2166 | * If the tracing is enabled, go ahead and enable the record. | |
2167 | * | |
2168 | * The reason not to enable the record immediatelly is the | |
2169 | * inherent check of ftrace_make_nop/ftrace_make_call for | |
2170 | * correct previous instructions. Making first the NOP | |
2171 | * conversion puts the module to the correct state, thus | |
2172 | * passing the ftrace_make_call check. | |
2173 | */ | |
2174 | if (ftrace_start_up && ref) { | |
2175 | int failed = __ftrace_replace_code(p, 1); | |
2176 | if (failed) | |
2177 | ftrace_bug(failed, p->ip); | |
2178 | } | |
5cb084bb | 2179 | } |
3d083395 SR |
2180 | } |
2181 | ||
85ae32ae SR |
2182 | ftrace_new_pgs = NULL; |
2183 | ||
750ed1a4 | 2184 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
2185 | ftrace_update_time = stop - start; |
2186 | ftrace_update_tot_cnt += ftrace_update_cnt; | |
2187 | ||
16444a8a ACM |
2188 | return 0; |
2189 | } | |
2190 | ||
a7900875 | 2191 | static int ftrace_allocate_records(struct ftrace_page *pg, int count) |
3c1720f0 | 2192 | { |
a7900875 | 2193 | int order; |
3c1720f0 | 2194 | int cnt; |
3c1720f0 | 2195 | |
a7900875 SR |
2196 | if (WARN_ON(!count)) |
2197 | return -EINVAL; | |
2198 | ||
2199 | order = get_count_order(DIV_ROUND_UP(count, ENTRIES_PER_PAGE)); | |
3c1720f0 SR |
2200 | |
2201 | /* | |
a7900875 SR |
2202 | * We want to fill as much as possible. No more than a page |
2203 | * may be empty. | |
3c1720f0 | 2204 | */ |
a7900875 SR |
2205 | while ((PAGE_SIZE << order) / ENTRY_SIZE >= count + ENTRIES_PER_PAGE) |
2206 | order--; | |
3c1720f0 | 2207 | |
a7900875 SR |
2208 | again: |
2209 | pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); | |
3c1720f0 | 2210 | |
a7900875 SR |
2211 | if (!pg->records) { |
2212 | /* if we can't allocate this size, try something smaller */ | |
2213 | if (!order) | |
2214 | return -ENOMEM; | |
2215 | order >>= 1; | |
2216 | goto again; | |
2217 | } | |
3c1720f0 | 2218 | |
a7900875 SR |
2219 | cnt = (PAGE_SIZE << order) / ENTRY_SIZE; |
2220 | pg->size = cnt; | |
3c1720f0 | 2221 | |
a7900875 SR |
2222 | if (cnt > count) |
2223 | cnt = count; | |
2224 | ||
2225 | return cnt; | |
2226 | } | |
2227 | ||
2228 | static struct ftrace_page * | |
2229 | ftrace_allocate_pages(unsigned long num_to_init) | |
2230 | { | |
2231 | struct ftrace_page *start_pg; | |
2232 | struct ftrace_page *pg; | |
2233 | int order; | |
2234 | int cnt; | |
2235 | ||
2236 | if (!num_to_init) | |
2237 | return 0; | |
2238 | ||
2239 | start_pg = pg = kzalloc(sizeof(*pg), GFP_KERNEL); | |
2240 | if (!pg) | |
2241 | return NULL; | |
2242 | ||
2243 | /* | |
2244 | * Try to allocate as much as possible in one continues | |
2245 | * location that fills in all of the space. We want to | |
2246 | * waste as little space as possible. | |
2247 | */ | |
2248 | for (;;) { | |
2249 | cnt = ftrace_allocate_records(pg, num_to_init); | |
2250 | if (cnt < 0) | |
2251 | goto free_pages; | |
2252 | ||
2253 | num_to_init -= cnt; | |
2254 | if (!num_to_init) | |
3c1720f0 SR |
2255 | break; |
2256 | ||
a7900875 SR |
2257 | pg->next = kzalloc(sizeof(*pg), GFP_KERNEL); |
2258 | if (!pg->next) | |
2259 | goto free_pages; | |
2260 | ||
3c1720f0 SR |
2261 | pg = pg->next; |
2262 | } | |
2263 | ||
a7900875 SR |
2264 | return start_pg; |
2265 | ||
2266 | free_pages: | |
2267 | while (start_pg) { | |
2268 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); | |
2269 | free_pages((unsigned long)pg->records, order); | |
2270 | start_pg = pg->next; | |
2271 | kfree(pg); | |
2272 | pg = start_pg; | |
2273 | } | |
2274 | pr_info("ftrace: FAILED to allocate memory for functions\n"); | |
2275 | return NULL; | |
2276 | } | |
2277 | ||
2278 | static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) | |
2279 | { | |
2280 | int cnt; | |
2281 | ||
2282 | if (!num_to_init) { | |
2283 | pr_info("ftrace: No functions to be traced?\n"); | |
2284 | return -1; | |
2285 | } | |
2286 | ||
2287 | cnt = num_to_init / ENTRIES_PER_PAGE; | |
2288 | pr_info("ftrace: allocating %ld entries in %d pages\n", | |
2289 | num_to_init, cnt + 1); | |
2290 | ||
3c1720f0 SR |
2291 | return 0; |
2292 | } | |
2293 | ||
5072c59f SR |
2294 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ |
2295 | ||
2296 | struct ftrace_iterator { | |
98c4fd04 | 2297 | loff_t pos; |
4aeb6967 SR |
2298 | loff_t func_pos; |
2299 | struct ftrace_page *pg; | |
2300 | struct dyn_ftrace *func; | |
2301 | struct ftrace_func_probe *probe; | |
2302 | struct trace_parser parser; | |
1cf41dd7 | 2303 | struct ftrace_hash *hash; |
33dc9b12 | 2304 | struct ftrace_ops *ops; |
4aeb6967 SR |
2305 | int hidx; |
2306 | int idx; | |
2307 | unsigned flags; | |
5072c59f SR |
2308 | }; |
2309 | ||
8fc0c701 | 2310 | static void * |
4aeb6967 | 2311 | t_hash_next(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
2312 | { |
2313 | struct ftrace_iterator *iter = m->private; | |
4aeb6967 | 2314 | struct hlist_node *hnd = NULL; |
8fc0c701 SR |
2315 | struct hlist_head *hhd; |
2316 | ||
8fc0c701 | 2317 | (*pos)++; |
98c4fd04 | 2318 | iter->pos = *pos; |
8fc0c701 | 2319 | |
4aeb6967 SR |
2320 | if (iter->probe) |
2321 | hnd = &iter->probe->node; | |
8fc0c701 SR |
2322 | retry: |
2323 | if (iter->hidx >= FTRACE_FUNC_HASHSIZE) | |
2324 | return NULL; | |
2325 | ||
2326 | hhd = &ftrace_func_hash[iter->hidx]; | |
2327 | ||
2328 | if (hlist_empty(hhd)) { | |
2329 | iter->hidx++; | |
2330 | hnd = NULL; | |
2331 | goto retry; | |
2332 | } | |
2333 | ||
2334 | if (!hnd) | |
2335 | hnd = hhd->first; | |
2336 | else { | |
2337 | hnd = hnd->next; | |
2338 | if (!hnd) { | |
2339 | iter->hidx++; | |
2340 | goto retry; | |
2341 | } | |
2342 | } | |
2343 | ||
4aeb6967 SR |
2344 | if (WARN_ON_ONCE(!hnd)) |
2345 | return NULL; | |
2346 | ||
2347 | iter->probe = hlist_entry(hnd, struct ftrace_func_probe, node); | |
2348 | ||
2349 | return iter; | |
8fc0c701 SR |
2350 | } |
2351 | ||
2352 | static void *t_hash_start(struct seq_file *m, loff_t *pos) | |
2353 | { | |
2354 | struct ftrace_iterator *iter = m->private; | |
2355 | void *p = NULL; | |
d82d6244 LZ |
2356 | loff_t l; |
2357 | ||
69a3083c SR |
2358 | if (!(iter->flags & FTRACE_ITER_DO_HASH)) |
2359 | return NULL; | |
2360 | ||
2bccfffd SR |
2361 | if (iter->func_pos > *pos) |
2362 | return NULL; | |
8fc0c701 | 2363 | |
d82d6244 | 2364 | iter->hidx = 0; |
2bccfffd | 2365 | for (l = 0; l <= (*pos - iter->func_pos); ) { |
4aeb6967 | 2366 | p = t_hash_next(m, &l); |
d82d6244 LZ |
2367 | if (!p) |
2368 | break; | |
2369 | } | |
4aeb6967 SR |
2370 | if (!p) |
2371 | return NULL; | |
2372 | ||
98c4fd04 SR |
2373 | /* Only set this if we have an item */ |
2374 | iter->flags |= FTRACE_ITER_HASH; | |
2375 | ||
4aeb6967 | 2376 | return iter; |
8fc0c701 SR |
2377 | } |
2378 | ||
4aeb6967 SR |
2379 | static int |
2380 | t_hash_show(struct seq_file *m, struct ftrace_iterator *iter) | |
8fc0c701 | 2381 | { |
b6887d79 | 2382 | struct ftrace_func_probe *rec; |
8fc0c701 | 2383 | |
4aeb6967 SR |
2384 | rec = iter->probe; |
2385 | if (WARN_ON_ONCE(!rec)) | |
2386 | return -EIO; | |
8fc0c701 | 2387 | |
809dcf29 SR |
2388 | if (rec->ops->print) |
2389 | return rec->ops->print(m, rec->ip, rec->ops, rec->data); | |
2390 | ||
b375a11a | 2391 | seq_printf(m, "%ps:%ps", (void *)rec->ip, (void *)rec->ops->func); |
8fc0c701 SR |
2392 | |
2393 | if (rec->data) | |
2394 | seq_printf(m, ":%p", rec->data); | |
2395 | seq_putc(m, '\n'); | |
2396 | ||
2397 | return 0; | |
2398 | } | |
2399 | ||
e309b41d | 2400 | static void * |
5072c59f SR |
2401 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2402 | { | |
2403 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 2404 | struct ftrace_ops *ops = iter->ops; |
5072c59f SR |
2405 | struct dyn_ftrace *rec = NULL; |
2406 | ||
45a4a237 SR |
2407 | if (unlikely(ftrace_disabled)) |
2408 | return NULL; | |
2409 | ||
8fc0c701 | 2410 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 2411 | return t_hash_next(m, pos); |
8fc0c701 | 2412 | |
5072c59f | 2413 | (*pos)++; |
1106b699 | 2414 | iter->pos = iter->func_pos = *pos; |
5072c59f | 2415 | |
0c75a3ed | 2416 | if (iter->flags & FTRACE_ITER_PRINTALL) |
57c072c7 | 2417 | return t_hash_start(m, pos); |
0c75a3ed | 2418 | |
5072c59f SR |
2419 | retry: |
2420 | if (iter->idx >= iter->pg->index) { | |
2421 | if (iter->pg->next) { | |
2422 | iter->pg = iter->pg->next; | |
2423 | iter->idx = 0; | |
2424 | goto retry; | |
2425 | } | |
2426 | } else { | |
2427 | rec = &iter->pg->records[iter->idx++]; | |
32082309 | 2428 | if (((iter->flags & FTRACE_ITER_FILTER) && |
f45948e8 | 2429 | !(ftrace_lookup_ip(ops->filter_hash, rec->ip))) || |
0183fb1c | 2430 | |
41c52c0d | 2431 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
647bcd03 SR |
2432 | !ftrace_lookup_ip(ops->notrace_hash, rec->ip)) || |
2433 | ||
2434 | ((iter->flags & FTRACE_ITER_ENABLED) && | |
2435 | !(rec->flags & ~FTRACE_FL_MASK))) { | |
2436 | ||
5072c59f SR |
2437 | rec = NULL; |
2438 | goto retry; | |
2439 | } | |
2440 | } | |
2441 | ||
4aeb6967 | 2442 | if (!rec) |
57c072c7 | 2443 | return t_hash_start(m, pos); |
4aeb6967 SR |
2444 | |
2445 | iter->func = rec; | |
2446 | ||
2447 | return iter; | |
5072c59f SR |
2448 | } |
2449 | ||
98c4fd04 SR |
2450 | static void reset_iter_read(struct ftrace_iterator *iter) |
2451 | { | |
2452 | iter->pos = 0; | |
2453 | iter->func_pos = 0; | |
70f77b3f | 2454 | iter->flags &= ~(FTRACE_ITER_PRINTALL | FTRACE_ITER_HASH); |
5072c59f SR |
2455 | } |
2456 | ||
2457 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2458 | { | |
2459 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 2460 | struct ftrace_ops *ops = iter->ops; |
5072c59f | 2461 | void *p = NULL; |
694ce0a5 | 2462 | loff_t l; |
5072c59f | 2463 | |
8fc0c701 | 2464 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
2465 | |
2466 | if (unlikely(ftrace_disabled)) | |
2467 | return NULL; | |
2468 | ||
98c4fd04 SR |
2469 | /* |
2470 | * If an lseek was done, then reset and start from beginning. | |
2471 | */ | |
2472 | if (*pos < iter->pos) | |
2473 | reset_iter_read(iter); | |
2474 | ||
0c75a3ed SR |
2475 | /* |
2476 | * For set_ftrace_filter reading, if we have the filter | |
2477 | * off, we can short cut and just print out that all | |
2478 | * functions are enabled. | |
2479 | */ | |
06a51d93 SR |
2480 | if (iter->flags & FTRACE_ITER_FILTER && |
2481 | ftrace_hash_empty(ops->filter_hash)) { | |
0c75a3ed | 2482 | if (*pos > 0) |
8fc0c701 | 2483 | return t_hash_start(m, pos); |
0c75a3ed | 2484 | iter->flags |= FTRACE_ITER_PRINTALL; |
df091625 CW |
2485 | /* reset in case of seek/pread */ |
2486 | iter->flags &= ~FTRACE_ITER_HASH; | |
0c75a3ed SR |
2487 | return iter; |
2488 | } | |
2489 | ||
8fc0c701 SR |
2490 | if (iter->flags & FTRACE_ITER_HASH) |
2491 | return t_hash_start(m, pos); | |
2492 | ||
98c4fd04 SR |
2493 | /* |
2494 | * Unfortunately, we need to restart at ftrace_pages_start | |
2495 | * every time we let go of the ftrace_mutex. This is because | |
2496 | * those pointers can change without the lock. | |
2497 | */ | |
694ce0a5 LZ |
2498 | iter->pg = ftrace_pages_start; |
2499 | iter->idx = 0; | |
2500 | for (l = 0; l <= *pos; ) { | |
2501 | p = t_next(m, p, &l); | |
2502 | if (!p) | |
2503 | break; | |
50cdaf08 | 2504 | } |
5821e1b7 | 2505 | |
69a3083c SR |
2506 | if (!p) |
2507 | return t_hash_start(m, pos); | |
4aeb6967 SR |
2508 | |
2509 | return iter; | |
5072c59f SR |
2510 | } |
2511 | ||
2512 | static void t_stop(struct seq_file *m, void *p) | |
2513 | { | |
8fc0c701 | 2514 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
2515 | } |
2516 | ||
2517 | static int t_show(struct seq_file *m, void *v) | |
2518 | { | |
0c75a3ed | 2519 | struct ftrace_iterator *iter = m->private; |
4aeb6967 | 2520 | struct dyn_ftrace *rec; |
5072c59f | 2521 | |
8fc0c701 | 2522 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 2523 | return t_hash_show(m, iter); |
8fc0c701 | 2524 | |
0c75a3ed SR |
2525 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
2526 | seq_printf(m, "#### all functions enabled ####\n"); | |
2527 | return 0; | |
2528 | } | |
2529 | ||
4aeb6967 SR |
2530 | rec = iter->func; |
2531 | ||
5072c59f SR |
2532 | if (!rec) |
2533 | return 0; | |
2534 | ||
647bcd03 SR |
2535 | seq_printf(m, "%ps", (void *)rec->ip); |
2536 | if (iter->flags & FTRACE_ITER_ENABLED) | |
08f6fba5 SR |
2537 | seq_printf(m, " (%ld)%s", |
2538 | rec->flags & ~FTRACE_FL_MASK, | |
2539 | rec->flags & FTRACE_FL_REGS ? " R" : ""); | |
647bcd03 | 2540 | seq_printf(m, "\n"); |
5072c59f SR |
2541 | |
2542 | return 0; | |
2543 | } | |
2544 | ||
88e9d34c | 2545 | static const struct seq_operations show_ftrace_seq_ops = { |
5072c59f SR |
2546 | .start = t_start, |
2547 | .next = t_next, | |
2548 | .stop = t_stop, | |
2549 | .show = t_show, | |
2550 | }; | |
2551 | ||
e309b41d | 2552 | static int |
5072c59f SR |
2553 | ftrace_avail_open(struct inode *inode, struct file *file) |
2554 | { | |
2555 | struct ftrace_iterator *iter; | |
5072c59f | 2556 | |
4eebcc81 SR |
2557 | if (unlikely(ftrace_disabled)) |
2558 | return -ENODEV; | |
2559 | ||
50e18b94 JO |
2560 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
2561 | if (iter) { | |
2562 | iter->pg = ftrace_pages_start; | |
2563 | iter->ops = &global_ops; | |
4bf39a94 | 2564 | } |
5072c59f | 2565 | |
50e18b94 | 2566 | return iter ? 0 : -ENOMEM; |
5072c59f SR |
2567 | } |
2568 | ||
647bcd03 SR |
2569 | static int |
2570 | ftrace_enabled_open(struct inode *inode, struct file *file) | |
2571 | { | |
2572 | struct ftrace_iterator *iter; | |
647bcd03 SR |
2573 | |
2574 | if (unlikely(ftrace_disabled)) | |
2575 | return -ENODEV; | |
2576 | ||
50e18b94 JO |
2577 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
2578 | if (iter) { | |
2579 | iter->pg = ftrace_pages_start; | |
2580 | iter->flags = FTRACE_ITER_ENABLED; | |
2581 | iter->ops = &global_ops; | |
647bcd03 SR |
2582 | } |
2583 | ||
50e18b94 | 2584 | return iter ? 0 : -ENOMEM; |
647bcd03 SR |
2585 | } |
2586 | ||
1cf41dd7 | 2587 | static void ftrace_filter_reset(struct ftrace_hash *hash) |
5072c59f | 2588 | { |
52baf119 | 2589 | mutex_lock(&ftrace_lock); |
1cf41dd7 | 2590 | ftrace_hash_clear(hash); |
52baf119 | 2591 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
2592 | } |
2593 | ||
fc13cb0c SR |
2594 | /** |
2595 | * ftrace_regex_open - initialize function tracer filter files | |
2596 | * @ops: The ftrace_ops that hold the hash filters | |
2597 | * @flag: The type of filter to process | |
2598 | * @inode: The inode, usually passed in to your open routine | |
2599 | * @file: The file, usually passed in to your open routine | |
2600 | * | |
2601 | * ftrace_regex_open() initializes the filter files for the | |
2602 | * @ops. Depending on @flag it may process the filter hash or | |
2603 | * the notrace hash of @ops. With this called from the open | |
2604 | * routine, you can use ftrace_filter_write() for the write | |
2605 | * routine if @flag has FTRACE_ITER_FILTER set, or | |
2606 | * ftrace_notrace_write() if @flag has FTRACE_ITER_NOTRACE set. | |
2607 | * ftrace_regex_lseek() should be used as the lseek routine, and | |
2608 | * release must call ftrace_regex_release(). | |
2609 | */ | |
2610 | int | |
f45948e8 | 2611 | ftrace_regex_open(struct ftrace_ops *ops, int flag, |
1cf41dd7 | 2612 | struct inode *inode, struct file *file) |
5072c59f SR |
2613 | { |
2614 | struct ftrace_iterator *iter; | |
f45948e8 | 2615 | struct ftrace_hash *hash; |
5072c59f SR |
2616 | int ret = 0; |
2617 | ||
4eebcc81 SR |
2618 | if (unlikely(ftrace_disabled)) |
2619 | return -ENODEV; | |
2620 | ||
5072c59f SR |
2621 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
2622 | if (!iter) | |
2623 | return -ENOMEM; | |
2624 | ||
689fd8b6 | 2625 | if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) { |
2626 | kfree(iter); | |
2627 | return -ENOMEM; | |
2628 | } | |
2629 | ||
f45948e8 SR |
2630 | if (flag & FTRACE_ITER_NOTRACE) |
2631 | hash = ops->notrace_hash; | |
2632 | else | |
2633 | hash = ops->filter_hash; | |
2634 | ||
33dc9b12 SR |
2635 | iter->ops = ops; |
2636 | iter->flags = flag; | |
2637 | ||
2638 | if (file->f_mode & FMODE_WRITE) { | |
2639 | mutex_lock(&ftrace_lock); | |
2640 | iter->hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash); | |
2641 | mutex_unlock(&ftrace_lock); | |
2642 | ||
2643 | if (!iter->hash) { | |
2644 | trace_parser_put(&iter->parser); | |
2645 | kfree(iter); | |
2646 | return -ENOMEM; | |
2647 | } | |
2648 | } | |
1cf41dd7 | 2649 | |
41c52c0d | 2650 | mutex_lock(&ftrace_regex_lock); |
33dc9b12 | 2651 | |
5072c59f | 2652 | if ((file->f_mode & FMODE_WRITE) && |
8650ae32 | 2653 | (file->f_flags & O_TRUNC)) |
33dc9b12 | 2654 | ftrace_filter_reset(iter->hash); |
5072c59f SR |
2655 | |
2656 | if (file->f_mode & FMODE_READ) { | |
2657 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
2658 | |
2659 | ret = seq_open(file, &show_ftrace_seq_ops); | |
2660 | if (!ret) { | |
2661 | struct seq_file *m = file->private_data; | |
2662 | m->private = iter; | |
79fe249c | 2663 | } else { |
33dc9b12 SR |
2664 | /* Failed */ |
2665 | free_ftrace_hash(iter->hash); | |
79fe249c | 2666 | trace_parser_put(&iter->parser); |
5072c59f | 2667 | kfree(iter); |
79fe249c | 2668 | } |
5072c59f SR |
2669 | } else |
2670 | file->private_data = iter; | |
41c52c0d | 2671 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
2672 | |
2673 | return ret; | |
2674 | } | |
2675 | ||
41c52c0d SR |
2676 | static int |
2677 | ftrace_filter_open(struct inode *inode, struct file *file) | |
2678 | { | |
69a3083c SR |
2679 | return ftrace_regex_open(&global_ops, |
2680 | FTRACE_ITER_FILTER | FTRACE_ITER_DO_HASH, | |
2681 | inode, file); | |
41c52c0d SR |
2682 | } |
2683 | ||
2684 | static int | |
2685 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
2686 | { | |
f45948e8 | 2687 | return ftrace_regex_open(&global_ops, FTRACE_ITER_NOTRACE, |
1cf41dd7 | 2688 | inode, file); |
41c52c0d SR |
2689 | } |
2690 | ||
fc13cb0c | 2691 | loff_t |
965c8e59 | 2692 | ftrace_regex_lseek(struct file *file, loff_t offset, int whence) |
5072c59f SR |
2693 | { |
2694 | loff_t ret; | |
2695 | ||
2696 | if (file->f_mode & FMODE_READ) | |
965c8e59 | 2697 | ret = seq_lseek(file, offset, whence); |
5072c59f SR |
2698 | else |
2699 | file->f_pos = ret = 1; | |
2700 | ||
2701 | return ret; | |
2702 | } | |
2703 | ||
64e7c440 | 2704 | static int ftrace_match(char *str, char *regex, int len, int type) |
9f4801e3 | 2705 | { |
9f4801e3 | 2706 | int matched = 0; |
751e9983 | 2707 | int slen; |
9f4801e3 | 2708 | |
9f4801e3 SR |
2709 | switch (type) { |
2710 | case MATCH_FULL: | |
2711 | if (strcmp(str, regex) == 0) | |
2712 | matched = 1; | |
2713 | break; | |
2714 | case MATCH_FRONT_ONLY: | |
2715 | if (strncmp(str, regex, len) == 0) | |
2716 | matched = 1; | |
2717 | break; | |
2718 | case MATCH_MIDDLE_ONLY: | |
2719 | if (strstr(str, regex)) | |
2720 | matched = 1; | |
2721 | break; | |
2722 | case MATCH_END_ONLY: | |
751e9983 LZ |
2723 | slen = strlen(str); |
2724 | if (slen >= len && memcmp(str + slen - len, regex, len) == 0) | |
9f4801e3 SR |
2725 | matched = 1; |
2726 | break; | |
2727 | } | |
2728 | ||
2729 | return matched; | |
2730 | } | |
2731 | ||
b448c4e3 | 2732 | static int |
1cf41dd7 | 2733 | enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int not) |
996e87be | 2734 | { |
b448c4e3 | 2735 | struct ftrace_func_entry *entry; |
b448c4e3 SR |
2736 | int ret = 0; |
2737 | ||
1cf41dd7 SR |
2738 | entry = ftrace_lookup_ip(hash, rec->ip); |
2739 | if (not) { | |
2740 | /* Do nothing if it doesn't exist */ | |
2741 | if (!entry) | |
2742 | return 0; | |
b448c4e3 | 2743 | |
33dc9b12 | 2744 | free_hash_entry(hash, entry); |
1cf41dd7 SR |
2745 | } else { |
2746 | /* Do nothing if it exists */ | |
2747 | if (entry) | |
2748 | return 0; | |
b448c4e3 | 2749 | |
1cf41dd7 | 2750 | ret = add_hash_entry(hash, rec->ip); |
b448c4e3 SR |
2751 | } |
2752 | return ret; | |
996e87be SR |
2753 | } |
2754 | ||
64e7c440 | 2755 | static int |
b9df92d2 SR |
2756 | ftrace_match_record(struct dyn_ftrace *rec, char *mod, |
2757 | char *regex, int len, int type) | |
64e7c440 SR |
2758 | { |
2759 | char str[KSYM_SYMBOL_LEN]; | |
b9df92d2 SR |
2760 | char *modname; |
2761 | ||
2762 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); | |
2763 | ||
2764 | if (mod) { | |
2765 | /* module lookup requires matching the module */ | |
2766 | if (!modname || strcmp(modname, mod)) | |
2767 | return 0; | |
2768 | ||
2769 | /* blank search means to match all funcs in the mod */ | |
2770 | if (!len) | |
2771 | return 1; | |
2772 | } | |
64e7c440 | 2773 | |
64e7c440 SR |
2774 | return ftrace_match(str, regex, len, type); |
2775 | } | |
2776 | ||
1cf41dd7 SR |
2777 | static int |
2778 | match_records(struct ftrace_hash *hash, char *buff, | |
2779 | int len, char *mod, int not) | |
9f4801e3 | 2780 | { |
b9df92d2 | 2781 | unsigned search_len = 0; |
9f4801e3 SR |
2782 | struct ftrace_page *pg; |
2783 | struct dyn_ftrace *rec; | |
b9df92d2 SR |
2784 | int type = MATCH_FULL; |
2785 | char *search = buff; | |
311d16da | 2786 | int found = 0; |
b448c4e3 | 2787 | int ret; |
9f4801e3 | 2788 | |
b9df92d2 SR |
2789 | if (len) { |
2790 | type = filter_parse_regex(buff, len, &search, ¬); | |
2791 | search_len = strlen(search); | |
2792 | } | |
9f4801e3 | 2793 | |
52baf119 | 2794 | mutex_lock(&ftrace_lock); |
265c831c | 2795 | |
b9df92d2 SR |
2796 | if (unlikely(ftrace_disabled)) |
2797 | goto out_unlock; | |
9f4801e3 | 2798 | |
265c831c | 2799 | do_for_each_ftrace_rec(pg, rec) { |
b9df92d2 | 2800 | if (ftrace_match_record(rec, mod, search, search_len, type)) { |
1cf41dd7 | 2801 | ret = enter_record(hash, rec, not); |
b448c4e3 SR |
2802 | if (ret < 0) { |
2803 | found = ret; | |
2804 | goto out_unlock; | |
2805 | } | |
311d16da | 2806 | found = 1; |
265c831c SR |
2807 | } |
2808 | } while_for_each_ftrace_rec(); | |
b9df92d2 | 2809 | out_unlock: |
52baf119 | 2810 | mutex_unlock(&ftrace_lock); |
311d16da LZ |
2811 | |
2812 | return found; | |
5072c59f SR |
2813 | } |
2814 | ||
64e7c440 | 2815 | static int |
1cf41dd7 | 2816 | ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) |
64e7c440 | 2817 | { |
1cf41dd7 | 2818 | return match_records(hash, buff, len, NULL, 0); |
64e7c440 SR |
2819 | } |
2820 | ||
1cf41dd7 SR |
2821 | static int |
2822 | ftrace_match_module_records(struct ftrace_hash *hash, char *buff, char *mod) | |
64e7c440 | 2823 | { |
64e7c440 | 2824 | int not = 0; |
6a24a244 | 2825 | |
64e7c440 SR |
2826 | /* blank or '*' mean the same */ |
2827 | if (strcmp(buff, "*") == 0) | |
2828 | buff[0] = 0; | |
2829 | ||
2830 | /* handle the case of 'dont filter this module' */ | |
2831 | if (strcmp(buff, "!") == 0 || strcmp(buff, "!*") == 0) { | |
2832 | buff[0] = 0; | |
2833 | not = 1; | |
2834 | } | |
2835 | ||
1cf41dd7 | 2836 | return match_records(hash, buff, strlen(buff), mod, not); |
64e7c440 SR |
2837 | } |
2838 | ||
f6180773 SR |
2839 | /* |
2840 | * We register the module command as a template to show others how | |
2841 | * to register the a command as well. | |
2842 | */ | |
2843 | ||
2844 | static int | |
43dd61c9 SR |
2845 | ftrace_mod_callback(struct ftrace_hash *hash, |
2846 | char *func, char *cmd, char *param, int enable) | |
f6180773 SR |
2847 | { |
2848 | char *mod; | |
b448c4e3 | 2849 | int ret = -EINVAL; |
f6180773 SR |
2850 | |
2851 | /* | |
2852 | * cmd == 'mod' because we only registered this func | |
2853 | * for the 'mod' ftrace_func_command. | |
2854 | * But if you register one func with multiple commands, | |
2855 | * you can tell which command was used by the cmd | |
2856 | * parameter. | |
2857 | */ | |
2858 | ||
2859 | /* we must have a module name */ | |
2860 | if (!param) | |
b448c4e3 | 2861 | return ret; |
f6180773 SR |
2862 | |
2863 | mod = strsep(¶m, ":"); | |
2864 | if (!strlen(mod)) | |
b448c4e3 | 2865 | return ret; |
f6180773 | 2866 | |
1cf41dd7 | 2867 | ret = ftrace_match_module_records(hash, func, mod); |
b448c4e3 SR |
2868 | if (!ret) |
2869 | ret = -EINVAL; | |
2870 | if (ret < 0) | |
2871 | return ret; | |
2872 | ||
2873 | return 0; | |
f6180773 SR |
2874 | } |
2875 | ||
2876 | static struct ftrace_func_command ftrace_mod_cmd = { | |
2877 | .name = "mod", | |
2878 | .func = ftrace_mod_callback, | |
2879 | }; | |
2880 | ||
2881 | static int __init ftrace_mod_cmd_init(void) | |
2882 | { | |
2883 | return register_ftrace_command(&ftrace_mod_cmd); | |
2884 | } | |
6f415672 | 2885 | core_initcall(ftrace_mod_cmd_init); |
f6180773 | 2886 | |
2f5f6ad9 | 2887 | static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 2888 | struct ftrace_ops *op, struct pt_regs *pt_regs) |
59df055f | 2889 | { |
b6887d79 | 2890 | struct ftrace_func_probe *entry; |
59df055f SR |
2891 | struct hlist_head *hhd; |
2892 | struct hlist_node *n; | |
2893 | unsigned long key; | |
59df055f SR |
2894 | |
2895 | key = hash_long(ip, FTRACE_HASH_BITS); | |
2896 | ||
2897 | hhd = &ftrace_func_hash[key]; | |
2898 | ||
2899 | if (hlist_empty(hhd)) | |
2900 | return; | |
2901 | ||
2902 | /* | |
2903 | * Disable preemption for these calls to prevent a RCU grace | |
2904 | * period. This syncs the hash iteration and freeing of items | |
2905 | * on the hash. rcu_read_lock is too dangerous here. | |
2906 | */ | |
5168ae50 | 2907 | preempt_disable_notrace(); |
59df055f SR |
2908 | hlist_for_each_entry_rcu(entry, n, hhd, node) { |
2909 | if (entry->ip == ip) | |
2910 | entry->ops->func(ip, parent_ip, &entry->data); | |
2911 | } | |
5168ae50 | 2912 | preempt_enable_notrace(); |
59df055f SR |
2913 | } |
2914 | ||
b6887d79 | 2915 | static struct ftrace_ops trace_probe_ops __read_mostly = |
59df055f | 2916 | { |
fb9fb015 | 2917 | .func = function_trace_probe_call, |
59df055f SR |
2918 | }; |
2919 | ||
b6887d79 | 2920 | static int ftrace_probe_registered; |
59df055f | 2921 | |
b6887d79 | 2922 | static void __enable_ftrace_function_probe(void) |
59df055f | 2923 | { |
b848914c | 2924 | int ret; |
59df055f SR |
2925 | int i; |
2926 | ||
b6887d79 | 2927 | if (ftrace_probe_registered) |
59df055f SR |
2928 | return; |
2929 | ||
2930 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
2931 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
2932 | if (hhd->first) | |
2933 | break; | |
2934 | } | |
2935 | /* Nothing registered? */ | |
2936 | if (i == FTRACE_FUNC_HASHSIZE) | |
2937 | return; | |
2938 | ||
b848914c SR |
2939 | ret = __register_ftrace_function(&trace_probe_ops); |
2940 | if (!ret) | |
a1cd6173 | 2941 | ret = ftrace_startup(&trace_probe_ops, 0); |
b848914c | 2942 | |
b6887d79 | 2943 | ftrace_probe_registered = 1; |
59df055f SR |
2944 | } |
2945 | ||
b6887d79 | 2946 | static void __disable_ftrace_function_probe(void) |
59df055f | 2947 | { |
b848914c | 2948 | int ret; |
59df055f SR |
2949 | int i; |
2950 | ||
b6887d79 | 2951 | if (!ftrace_probe_registered) |
59df055f SR |
2952 | return; |
2953 | ||
2954 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
2955 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
2956 | if (hhd->first) | |
2957 | return; | |
2958 | } | |
2959 | ||
2960 | /* no more funcs left */ | |
b848914c SR |
2961 | ret = __unregister_ftrace_function(&trace_probe_ops); |
2962 | if (!ret) | |
2963 | ftrace_shutdown(&trace_probe_ops, 0); | |
2964 | ||
b6887d79 | 2965 | ftrace_probe_registered = 0; |
59df055f SR |
2966 | } |
2967 | ||
2968 | ||
2969 | static void ftrace_free_entry_rcu(struct rcu_head *rhp) | |
2970 | { | |
b6887d79 SR |
2971 | struct ftrace_func_probe *entry = |
2972 | container_of(rhp, struct ftrace_func_probe, rcu); | |
59df055f SR |
2973 | |
2974 | if (entry->ops->free) | |
2975 | entry->ops->free(&entry->data); | |
2976 | kfree(entry); | |
2977 | } | |
2978 | ||
2979 | ||
2980 | int | |
b6887d79 | 2981 | register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
2982 | void *data) |
2983 | { | |
b6887d79 | 2984 | struct ftrace_func_probe *entry; |
59df055f SR |
2985 | struct ftrace_page *pg; |
2986 | struct dyn_ftrace *rec; | |
59df055f | 2987 | int type, len, not; |
6a24a244 | 2988 | unsigned long key; |
59df055f SR |
2989 | int count = 0; |
2990 | char *search; | |
2991 | ||
3f6fe06d | 2992 | type = filter_parse_regex(glob, strlen(glob), &search, ¬); |
59df055f SR |
2993 | len = strlen(search); |
2994 | ||
b6887d79 | 2995 | /* we do not support '!' for function probes */ |
59df055f SR |
2996 | if (WARN_ON(not)) |
2997 | return -EINVAL; | |
2998 | ||
2999 | mutex_lock(&ftrace_lock); | |
59df055f | 3000 | |
45a4a237 SR |
3001 | if (unlikely(ftrace_disabled)) |
3002 | goto out_unlock; | |
59df055f | 3003 | |
45a4a237 | 3004 | do_for_each_ftrace_rec(pg, rec) { |
59df055f | 3005 | |
b9df92d2 | 3006 | if (!ftrace_match_record(rec, NULL, search, len, type)) |
59df055f SR |
3007 | continue; |
3008 | ||
3009 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
3010 | if (!entry) { | |
b6887d79 | 3011 | /* If we did not process any, then return error */ |
59df055f SR |
3012 | if (!count) |
3013 | count = -ENOMEM; | |
3014 | goto out_unlock; | |
3015 | } | |
3016 | ||
3017 | count++; | |
3018 | ||
3019 | entry->data = data; | |
3020 | ||
3021 | /* | |
3022 | * The caller might want to do something special | |
3023 | * for each function we find. We call the callback | |
3024 | * to give the caller an opportunity to do so. | |
3025 | */ | |
3026 | if (ops->callback) { | |
3027 | if (ops->callback(rec->ip, &entry->data) < 0) { | |
3028 | /* caller does not like this func */ | |
3029 | kfree(entry); | |
3030 | continue; | |
3031 | } | |
3032 | } | |
3033 | ||
3034 | entry->ops = ops; | |
3035 | entry->ip = rec->ip; | |
3036 | ||
3037 | key = hash_long(entry->ip, FTRACE_HASH_BITS); | |
3038 | hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]); | |
3039 | ||
3040 | } while_for_each_ftrace_rec(); | |
b6887d79 | 3041 | __enable_ftrace_function_probe(); |
59df055f SR |
3042 | |
3043 | out_unlock: | |
3044 | mutex_unlock(&ftrace_lock); | |
3045 | ||
3046 | return count; | |
3047 | } | |
3048 | ||
3049 | enum { | |
b6887d79 SR |
3050 | PROBE_TEST_FUNC = 1, |
3051 | PROBE_TEST_DATA = 2 | |
59df055f SR |
3052 | }; |
3053 | ||
3054 | static void | |
b6887d79 | 3055 | __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3056 | void *data, int flags) |
3057 | { | |
b6887d79 | 3058 | struct ftrace_func_probe *entry; |
59df055f SR |
3059 | struct hlist_node *n, *tmp; |
3060 | char str[KSYM_SYMBOL_LEN]; | |
3061 | int type = MATCH_FULL; | |
3062 | int i, len = 0; | |
3063 | char *search; | |
3064 | ||
b36461da | 3065 | if (glob && (strcmp(glob, "*") == 0 || !strlen(glob))) |
59df055f | 3066 | glob = NULL; |
b36461da | 3067 | else if (glob) { |
59df055f SR |
3068 | int not; |
3069 | ||
3f6fe06d | 3070 | type = filter_parse_regex(glob, strlen(glob), &search, ¬); |
59df055f SR |
3071 | len = strlen(search); |
3072 | ||
b6887d79 | 3073 | /* we do not support '!' for function probes */ |
59df055f SR |
3074 | if (WARN_ON(not)) |
3075 | return; | |
3076 | } | |
3077 | ||
3078 | mutex_lock(&ftrace_lock); | |
3079 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
3080 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3081 | ||
3082 | hlist_for_each_entry_safe(entry, n, tmp, hhd, node) { | |
3083 | ||
3084 | /* break up if statements for readability */ | |
b6887d79 | 3085 | if ((flags & PROBE_TEST_FUNC) && entry->ops != ops) |
59df055f SR |
3086 | continue; |
3087 | ||
b6887d79 | 3088 | if ((flags & PROBE_TEST_DATA) && entry->data != data) |
59df055f SR |
3089 | continue; |
3090 | ||
3091 | /* do this last, since it is the most expensive */ | |
3092 | if (glob) { | |
3093 | kallsyms_lookup(entry->ip, NULL, NULL, | |
3094 | NULL, str); | |
3095 | if (!ftrace_match(str, glob, len, type)) | |
3096 | continue; | |
3097 | } | |
3098 | ||
3099 | hlist_del(&entry->node); | |
3100 | call_rcu(&entry->rcu, ftrace_free_entry_rcu); | |
3101 | } | |
3102 | } | |
b6887d79 | 3103 | __disable_ftrace_function_probe(); |
59df055f SR |
3104 | mutex_unlock(&ftrace_lock); |
3105 | } | |
3106 | ||
3107 | void | |
b6887d79 | 3108 | unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3109 | void *data) |
3110 | { | |
b6887d79 SR |
3111 | __unregister_ftrace_function_probe(glob, ops, data, |
3112 | PROBE_TEST_FUNC | PROBE_TEST_DATA); | |
59df055f SR |
3113 | } |
3114 | ||
3115 | void | |
b6887d79 | 3116 | unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops) |
59df055f | 3117 | { |
b6887d79 | 3118 | __unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC); |
59df055f SR |
3119 | } |
3120 | ||
b6887d79 | 3121 | void unregister_ftrace_function_probe_all(char *glob) |
59df055f | 3122 | { |
b6887d79 | 3123 | __unregister_ftrace_function_probe(glob, NULL, NULL, 0); |
59df055f SR |
3124 | } |
3125 | ||
f6180773 SR |
3126 | static LIST_HEAD(ftrace_commands); |
3127 | static DEFINE_MUTEX(ftrace_cmd_mutex); | |
3128 | ||
3129 | int register_ftrace_command(struct ftrace_func_command *cmd) | |
3130 | { | |
3131 | struct ftrace_func_command *p; | |
3132 | int ret = 0; | |
3133 | ||
3134 | mutex_lock(&ftrace_cmd_mutex); | |
3135 | list_for_each_entry(p, &ftrace_commands, list) { | |
3136 | if (strcmp(cmd->name, p->name) == 0) { | |
3137 | ret = -EBUSY; | |
3138 | goto out_unlock; | |
3139 | } | |
3140 | } | |
3141 | list_add(&cmd->list, &ftrace_commands); | |
3142 | out_unlock: | |
3143 | mutex_unlock(&ftrace_cmd_mutex); | |
3144 | ||
3145 | return ret; | |
3146 | } | |
3147 | ||
3148 | int unregister_ftrace_command(struct ftrace_func_command *cmd) | |
3149 | { | |
3150 | struct ftrace_func_command *p, *n; | |
3151 | int ret = -ENODEV; | |
3152 | ||
3153 | mutex_lock(&ftrace_cmd_mutex); | |
3154 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { | |
3155 | if (strcmp(cmd->name, p->name) == 0) { | |
3156 | ret = 0; | |
3157 | list_del_init(&p->list); | |
3158 | goto out_unlock; | |
3159 | } | |
3160 | } | |
3161 | out_unlock: | |
3162 | mutex_unlock(&ftrace_cmd_mutex); | |
3163 | ||
3164 | return ret; | |
3165 | } | |
3166 | ||
33dc9b12 SR |
3167 | static int ftrace_process_regex(struct ftrace_hash *hash, |
3168 | char *buff, int len, int enable) | |
64e7c440 | 3169 | { |
f6180773 | 3170 | char *func, *command, *next = buff; |
6a24a244 | 3171 | struct ftrace_func_command *p; |
0aff1c0c | 3172 | int ret = -EINVAL; |
64e7c440 SR |
3173 | |
3174 | func = strsep(&next, ":"); | |
3175 | ||
3176 | if (!next) { | |
1cf41dd7 | 3177 | ret = ftrace_match_records(hash, func, len); |
b448c4e3 SR |
3178 | if (!ret) |
3179 | ret = -EINVAL; | |
3180 | if (ret < 0) | |
3181 | return ret; | |
3182 | return 0; | |
64e7c440 SR |
3183 | } |
3184 | ||
f6180773 | 3185 | /* command found */ |
64e7c440 SR |
3186 | |
3187 | command = strsep(&next, ":"); | |
3188 | ||
f6180773 SR |
3189 | mutex_lock(&ftrace_cmd_mutex); |
3190 | list_for_each_entry(p, &ftrace_commands, list) { | |
3191 | if (strcmp(p->name, command) == 0) { | |
43dd61c9 | 3192 | ret = p->func(hash, func, command, next, enable); |
f6180773 SR |
3193 | goto out_unlock; |
3194 | } | |
64e7c440 | 3195 | } |
f6180773 SR |
3196 | out_unlock: |
3197 | mutex_unlock(&ftrace_cmd_mutex); | |
64e7c440 | 3198 | |
f6180773 | 3199 | return ret; |
64e7c440 SR |
3200 | } |
3201 | ||
e309b41d | 3202 | static ssize_t |
41c52c0d SR |
3203 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
3204 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
3205 | { |
3206 | struct ftrace_iterator *iter; | |
689fd8b6 | 3207 | struct trace_parser *parser; |
3208 | ssize_t ret, read; | |
5072c59f | 3209 | |
4ba7978e | 3210 | if (!cnt) |
5072c59f SR |
3211 | return 0; |
3212 | ||
41c52c0d | 3213 | mutex_lock(&ftrace_regex_lock); |
5072c59f | 3214 | |
45a4a237 SR |
3215 | ret = -ENODEV; |
3216 | if (unlikely(ftrace_disabled)) | |
3217 | goto out_unlock; | |
3218 | ||
5072c59f SR |
3219 | if (file->f_mode & FMODE_READ) { |
3220 | struct seq_file *m = file->private_data; | |
3221 | iter = m->private; | |
3222 | } else | |
3223 | iter = file->private_data; | |
3224 | ||
689fd8b6 | 3225 | parser = &iter->parser; |
3226 | read = trace_get_user(parser, ubuf, cnt, ppos); | |
5072c59f | 3227 | |
4ba7978e | 3228 | if (read >= 0 && trace_parser_loaded(parser) && |
689fd8b6 | 3229 | !trace_parser_cont(parser)) { |
33dc9b12 | 3230 | ret = ftrace_process_regex(iter->hash, parser->buffer, |
689fd8b6 | 3231 | parser->idx, enable); |
313254a9 | 3232 | trace_parser_clear(parser); |
5072c59f | 3233 | if (ret) |
ed146b25 | 3234 | goto out_unlock; |
eda1e328 | 3235 | } |
5072c59f | 3236 | |
5072c59f | 3237 | ret = read; |
ed146b25 | 3238 | out_unlock: |
689fd8b6 | 3239 | mutex_unlock(&ftrace_regex_lock); |
ed146b25 | 3240 | |
5072c59f SR |
3241 | return ret; |
3242 | } | |
3243 | ||
fc13cb0c | 3244 | ssize_t |
41c52c0d SR |
3245 | ftrace_filter_write(struct file *file, const char __user *ubuf, |
3246 | size_t cnt, loff_t *ppos) | |
3247 | { | |
3248 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
3249 | } | |
3250 | ||
fc13cb0c | 3251 | ssize_t |
41c52c0d SR |
3252 | ftrace_notrace_write(struct file *file, const char __user *ubuf, |
3253 | size_t cnt, loff_t *ppos) | |
3254 | { | |
3255 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
3256 | } | |
3257 | ||
33dc9b12 | 3258 | static int |
647664ea MH |
3259 | ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) |
3260 | { | |
3261 | struct ftrace_func_entry *entry; | |
3262 | ||
3263 | if (!ftrace_location(ip)) | |
3264 | return -EINVAL; | |
3265 | ||
3266 | if (remove) { | |
3267 | entry = ftrace_lookup_ip(hash, ip); | |
3268 | if (!entry) | |
3269 | return -ENOENT; | |
3270 | free_hash_entry(hash, entry); | |
3271 | return 0; | |
3272 | } | |
3273 | ||
3274 | return add_hash_entry(hash, ip); | |
3275 | } | |
3276 | ||
3277 | static int | |
3278 | ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, | |
3279 | unsigned long ip, int remove, int reset, int enable) | |
41c52c0d | 3280 | { |
33dc9b12 | 3281 | struct ftrace_hash **orig_hash; |
f45948e8 | 3282 | struct ftrace_hash *hash; |
33dc9b12 | 3283 | int ret; |
f45948e8 | 3284 | |
936e074b SR |
3285 | /* All global ops uses the global ops filters */ |
3286 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) | |
3287 | ops = &global_ops; | |
3288 | ||
41c52c0d | 3289 | if (unlikely(ftrace_disabled)) |
33dc9b12 | 3290 | return -ENODEV; |
41c52c0d | 3291 | |
f45948e8 | 3292 | if (enable) |
33dc9b12 | 3293 | orig_hash = &ops->filter_hash; |
f45948e8 | 3294 | else |
33dc9b12 SR |
3295 | orig_hash = &ops->notrace_hash; |
3296 | ||
3297 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
3298 | if (!hash) | |
3299 | return -ENOMEM; | |
f45948e8 | 3300 | |
41c52c0d SR |
3301 | mutex_lock(&ftrace_regex_lock); |
3302 | if (reset) | |
1cf41dd7 | 3303 | ftrace_filter_reset(hash); |
ac483c44 JO |
3304 | if (buf && !ftrace_match_records(hash, buf, len)) { |
3305 | ret = -EINVAL; | |
3306 | goto out_regex_unlock; | |
3307 | } | |
647664ea MH |
3308 | if (ip) { |
3309 | ret = ftrace_match_addr(hash, ip, remove); | |
3310 | if (ret < 0) | |
3311 | goto out_regex_unlock; | |
3312 | } | |
33dc9b12 SR |
3313 | |
3314 | mutex_lock(&ftrace_lock); | |
41fb61c2 | 3315 | ret = ftrace_hash_move(ops, enable, orig_hash, hash); |
072126f4 SR |
3316 | if (!ret && ops->flags & FTRACE_OPS_FL_ENABLED |
3317 | && ftrace_enabled) | |
30fb6aa7 | 3318 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); |
072126f4 | 3319 | |
33dc9b12 SR |
3320 | mutex_unlock(&ftrace_lock); |
3321 | ||
ac483c44 | 3322 | out_regex_unlock: |
41c52c0d | 3323 | mutex_unlock(&ftrace_regex_lock); |
33dc9b12 SR |
3324 | |
3325 | free_ftrace_hash(hash); | |
3326 | return ret; | |
41c52c0d SR |
3327 | } |
3328 | ||
647664ea MH |
3329 | static int |
3330 | ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove, | |
3331 | int reset, int enable) | |
3332 | { | |
3333 | return ftrace_set_hash(ops, 0, 0, ip, remove, reset, enable); | |
3334 | } | |
3335 | ||
3336 | /** | |
3337 | * ftrace_set_filter_ip - set a function to filter on in ftrace by address | |
3338 | * @ops - the ops to set the filter with | |
3339 | * @ip - the address to add to or remove from the filter. | |
3340 | * @remove - non zero to remove the ip from the filter | |
3341 | * @reset - non zero to reset all filters before applying this filter. | |
3342 | * | |
3343 | * Filters denote which functions should be enabled when tracing is enabled | |
3344 | * If @ip is NULL, it failes to update filter. | |
3345 | */ | |
3346 | int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, | |
3347 | int remove, int reset) | |
3348 | { | |
3349 | return ftrace_set_addr(ops, ip, remove, reset, 1); | |
3350 | } | |
3351 | EXPORT_SYMBOL_GPL(ftrace_set_filter_ip); | |
3352 | ||
3353 | static int | |
3354 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, | |
3355 | int reset, int enable) | |
3356 | { | |
3357 | return ftrace_set_hash(ops, buf, len, 0, 0, reset, enable); | |
3358 | } | |
3359 | ||
77a2b37d SR |
3360 | /** |
3361 | * ftrace_set_filter - set a function to filter on in ftrace | |
936e074b SR |
3362 | * @ops - the ops to set the filter with |
3363 | * @buf - the string that holds the function filter text. | |
3364 | * @len - the length of the string. | |
3365 | * @reset - non zero to reset all filters before applying this filter. | |
3366 | * | |
3367 | * Filters denote which functions should be enabled when tracing is enabled. | |
3368 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
3369 | */ | |
ac483c44 | 3370 | int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
3371 | int len, int reset) |
3372 | { | |
ac483c44 | 3373 | return ftrace_set_regex(ops, buf, len, reset, 1); |
936e074b SR |
3374 | } |
3375 | EXPORT_SYMBOL_GPL(ftrace_set_filter); | |
3376 | ||
3377 | /** | |
3378 | * ftrace_set_notrace - set a function to not trace in ftrace | |
3379 | * @ops - the ops to set the notrace filter with | |
3380 | * @buf - the string that holds the function notrace text. | |
3381 | * @len - the length of the string. | |
3382 | * @reset - non zero to reset all filters before applying this filter. | |
3383 | * | |
3384 | * Notrace Filters denote which functions should not be enabled when tracing | |
3385 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
3386 | * for tracing. | |
3387 | */ | |
ac483c44 | 3388 | int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
3389 | int len, int reset) |
3390 | { | |
ac483c44 | 3391 | return ftrace_set_regex(ops, buf, len, reset, 0); |
936e074b SR |
3392 | } |
3393 | EXPORT_SYMBOL_GPL(ftrace_set_notrace); | |
3394 | /** | |
3395 | * ftrace_set_filter - set a function to filter on in ftrace | |
3396 | * @ops - the ops to set the filter with | |
77a2b37d SR |
3397 | * @buf - the string that holds the function filter text. |
3398 | * @len - the length of the string. | |
3399 | * @reset - non zero to reset all filters before applying this filter. | |
3400 | * | |
3401 | * Filters denote which functions should be enabled when tracing is enabled. | |
3402 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
3403 | */ | |
936e074b | 3404 | void ftrace_set_global_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 3405 | { |
f45948e8 | 3406 | ftrace_set_regex(&global_ops, buf, len, reset, 1); |
41c52c0d | 3407 | } |
936e074b | 3408 | EXPORT_SYMBOL_GPL(ftrace_set_global_filter); |
4eebcc81 | 3409 | |
41c52c0d SR |
3410 | /** |
3411 | * ftrace_set_notrace - set a function to not trace in ftrace | |
936e074b | 3412 | * @ops - the ops to set the notrace filter with |
41c52c0d SR |
3413 | * @buf - the string that holds the function notrace text. |
3414 | * @len - the length of the string. | |
3415 | * @reset - non zero to reset all filters before applying this filter. | |
3416 | * | |
3417 | * Notrace Filters denote which functions should not be enabled when tracing | |
3418 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
3419 | * for tracing. | |
3420 | */ | |
936e074b | 3421 | void ftrace_set_global_notrace(unsigned char *buf, int len, int reset) |
41c52c0d | 3422 | { |
f45948e8 | 3423 | ftrace_set_regex(&global_ops, buf, len, reset, 0); |
77a2b37d | 3424 | } |
936e074b | 3425 | EXPORT_SYMBOL_GPL(ftrace_set_global_notrace); |
77a2b37d | 3426 | |
2af15d6a SR |
3427 | /* |
3428 | * command line interface to allow users to set filters on boot up. | |
3429 | */ | |
3430 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE | |
3431 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; | |
3432 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; | |
3433 | ||
3434 | static int __init set_ftrace_notrace(char *str) | |
3435 | { | |
3436 | strncpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); | |
3437 | return 1; | |
3438 | } | |
3439 | __setup("ftrace_notrace=", set_ftrace_notrace); | |
3440 | ||
3441 | static int __init set_ftrace_filter(char *str) | |
3442 | { | |
3443 | strncpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); | |
3444 | return 1; | |
3445 | } | |
3446 | __setup("ftrace_filter=", set_ftrace_filter); | |
3447 | ||
369bc18f | 3448 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
f6060f46 | 3449 | static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; |
801c29fd SR |
3450 | static int ftrace_set_func(unsigned long *array, int *idx, char *buffer); |
3451 | ||
369bc18f SA |
3452 | static int __init set_graph_function(char *str) |
3453 | { | |
06f43d66 | 3454 | strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); |
369bc18f SA |
3455 | return 1; |
3456 | } | |
3457 | __setup("ftrace_graph_filter=", set_graph_function); | |
3458 | ||
3459 | static void __init set_ftrace_early_graph(char *buf) | |
3460 | { | |
3461 | int ret; | |
3462 | char *func; | |
3463 | ||
3464 | while (buf) { | |
3465 | func = strsep(&buf, ","); | |
3466 | /* we allow only one expression at a time */ | |
3467 | ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, | |
3468 | func); | |
3469 | if (ret) | |
3470 | printk(KERN_DEBUG "ftrace: function %s not " | |
3471 | "traceable\n", func); | |
3472 | } | |
3473 | } | |
3474 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
3475 | ||
2a85a37f SR |
3476 | void __init |
3477 | ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable) | |
2af15d6a SR |
3478 | { |
3479 | char *func; | |
3480 | ||
3481 | while (buf) { | |
3482 | func = strsep(&buf, ","); | |
f45948e8 | 3483 | ftrace_set_regex(ops, func, strlen(func), 0, enable); |
2af15d6a SR |
3484 | } |
3485 | } | |
3486 | ||
3487 | static void __init set_ftrace_early_filters(void) | |
3488 | { | |
3489 | if (ftrace_filter_buf[0]) | |
2a85a37f | 3490 | ftrace_set_early_filter(&global_ops, ftrace_filter_buf, 1); |
2af15d6a | 3491 | if (ftrace_notrace_buf[0]) |
2a85a37f | 3492 | ftrace_set_early_filter(&global_ops, ftrace_notrace_buf, 0); |
369bc18f SA |
3493 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
3494 | if (ftrace_graph_buf[0]) | |
3495 | set_ftrace_early_graph(ftrace_graph_buf); | |
3496 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
2af15d6a SR |
3497 | } |
3498 | ||
fc13cb0c | 3499 | int ftrace_regex_release(struct inode *inode, struct file *file) |
5072c59f SR |
3500 | { |
3501 | struct seq_file *m = (struct seq_file *)file->private_data; | |
3502 | struct ftrace_iterator *iter; | |
33dc9b12 | 3503 | struct ftrace_hash **orig_hash; |
689fd8b6 | 3504 | struct trace_parser *parser; |
ed926f9b | 3505 | int filter_hash; |
33dc9b12 | 3506 | int ret; |
5072c59f | 3507 | |
41c52c0d | 3508 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
3509 | if (file->f_mode & FMODE_READ) { |
3510 | iter = m->private; | |
3511 | ||
3512 | seq_release(inode, file); | |
3513 | } else | |
3514 | iter = file->private_data; | |
3515 | ||
689fd8b6 | 3516 | parser = &iter->parser; |
3517 | if (trace_parser_loaded(parser)) { | |
3518 | parser->buffer[parser->idx] = 0; | |
1cf41dd7 | 3519 | ftrace_match_records(iter->hash, parser->buffer, parser->idx); |
5072c59f SR |
3520 | } |
3521 | ||
689fd8b6 | 3522 | trace_parser_put(parser); |
689fd8b6 | 3523 | |
058e297d | 3524 | if (file->f_mode & FMODE_WRITE) { |
ed926f9b SR |
3525 | filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); |
3526 | ||
3527 | if (filter_hash) | |
33dc9b12 | 3528 | orig_hash = &iter->ops->filter_hash; |
ed926f9b SR |
3529 | else |
3530 | orig_hash = &iter->ops->notrace_hash; | |
33dc9b12 | 3531 | |
058e297d | 3532 | mutex_lock(&ftrace_lock); |
41fb61c2 SR |
3533 | ret = ftrace_hash_move(iter->ops, filter_hash, |
3534 | orig_hash, iter->hash); | |
3535 | if (!ret && (iter->ops->flags & FTRACE_OPS_FL_ENABLED) | |
3536 | && ftrace_enabled) | |
30fb6aa7 | 3537 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); |
41fb61c2 | 3538 | |
058e297d SR |
3539 | mutex_unlock(&ftrace_lock); |
3540 | } | |
33dc9b12 SR |
3541 | free_ftrace_hash(iter->hash); |
3542 | kfree(iter); | |
058e297d | 3543 | |
41c52c0d | 3544 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
3545 | return 0; |
3546 | } | |
3547 | ||
5e2336a0 | 3548 | static const struct file_operations ftrace_avail_fops = { |
5072c59f SR |
3549 | .open = ftrace_avail_open, |
3550 | .read = seq_read, | |
3551 | .llseek = seq_lseek, | |
3be04b47 | 3552 | .release = seq_release_private, |
5072c59f SR |
3553 | }; |
3554 | ||
647bcd03 SR |
3555 | static const struct file_operations ftrace_enabled_fops = { |
3556 | .open = ftrace_enabled_open, | |
3557 | .read = seq_read, | |
3558 | .llseek = seq_lseek, | |
3559 | .release = seq_release_private, | |
3560 | }; | |
3561 | ||
5e2336a0 | 3562 | static const struct file_operations ftrace_filter_fops = { |
5072c59f | 3563 | .open = ftrace_filter_open, |
850a80cf | 3564 | .read = seq_read, |
5072c59f | 3565 | .write = ftrace_filter_write, |
98c4fd04 | 3566 | .llseek = ftrace_regex_lseek, |
1cf41dd7 | 3567 | .release = ftrace_regex_release, |
5072c59f SR |
3568 | }; |
3569 | ||
5e2336a0 | 3570 | static const struct file_operations ftrace_notrace_fops = { |
41c52c0d | 3571 | .open = ftrace_notrace_open, |
850a80cf | 3572 | .read = seq_read, |
41c52c0d SR |
3573 | .write = ftrace_notrace_write, |
3574 | .llseek = ftrace_regex_lseek, | |
1cf41dd7 | 3575 | .release = ftrace_regex_release, |
41c52c0d SR |
3576 | }; |
3577 | ||
ea4e2bc4 SR |
3578 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
3579 | ||
3580 | static DEFINE_MUTEX(graph_lock); | |
3581 | ||
3582 | int ftrace_graph_count; | |
c7c6b1fe | 3583 | int ftrace_graph_filter_enabled; |
ea4e2bc4 SR |
3584 | unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; |
3585 | ||
3586 | static void * | |
85951842 | 3587 | __g_next(struct seq_file *m, loff_t *pos) |
ea4e2bc4 | 3588 | { |
85951842 | 3589 | if (*pos >= ftrace_graph_count) |
ea4e2bc4 | 3590 | return NULL; |
a4ec5e0c | 3591 | return &ftrace_graph_funcs[*pos]; |
85951842 | 3592 | } |
ea4e2bc4 | 3593 | |
85951842 LZ |
3594 | static void * |
3595 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
3596 | { | |
3597 | (*pos)++; | |
3598 | return __g_next(m, pos); | |
ea4e2bc4 SR |
3599 | } |
3600 | ||
3601 | static void *g_start(struct seq_file *m, loff_t *pos) | |
3602 | { | |
ea4e2bc4 SR |
3603 | mutex_lock(&graph_lock); |
3604 | ||
f9349a8f | 3605 | /* Nothing, tell g_show to print all functions are enabled */ |
c7c6b1fe | 3606 | if (!ftrace_graph_filter_enabled && !*pos) |
f9349a8f FW |
3607 | return (void *)1; |
3608 | ||
85951842 | 3609 | return __g_next(m, pos); |
ea4e2bc4 SR |
3610 | } |
3611 | ||
3612 | static void g_stop(struct seq_file *m, void *p) | |
3613 | { | |
3614 | mutex_unlock(&graph_lock); | |
3615 | } | |
3616 | ||
3617 | static int g_show(struct seq_file *m, void *v) | |
3618 | { | |
3619 | unsigned long *ptr = v; | |
ea4e2bc4 SR |
3620 | |
3621 | if (!ptr) | |
3622 | return 0; | |
3623 | ||
f9349a8f FW |
3624 | if (ptr == (unsigned long *)1) { |
3625 | seq_printf(m, "#### all functions enabled ####\n"); | |
3626 | return 0; | |
3627 | } | |
3628 | ||
b375a11a | 3629 | seq_printf(m, "%ps\n", (void *)*ptr); |
ea4e2bc4 SR |
3630 | |
3631 | return 0; | |
3632 | } | |
3633 | ||
88e9d34c | 3634 | static const struct seq_operations ftrace_graph_seq_ops = { |
ea4e2bc4 SR |
3635 | .start = g_start, |
3636 | .next = g_next, | |
3637 | .stop = g_stop, | |
3638 | .show = g_show, | |
3639 | }; | |
3640 | ||
3641 | static int | |
3642 | ftrace_graph_open(struct inode *inode, struct file *file) | |
3643 | { | |
3644 | int ret = 0; | |
3645 | ||
3646 | if (unlikely(ftrace_disabled)) | |
3647 | return -ENODEV; | |
3648 | ||
3649 | mutex_lock(&graph_lock); | |
3650 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 3651 | (file->f_flags & O_TRUNC)) { |
c7c6b1fe | 3652 | ftrace_graph_filter_enabled = 0; |
ea4e2bc4 SR |
3653 | ftrace_graph_count = 0; |
3654 | memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); | |
3655 | } | |
a4ec5e0c | 3656 | mutex_unlock(&graph_lock); |
ea4e2bc4 | 3657 | |
a4ec5e0c | 3658 | if (file->f_mode & FMODE_READ) |
ea4e2bc4 | 3659 | ret = seq_open(file, &ftrace_graph_seq_ops); |
ea4e2bc4 SR |
3660 | |
3661 | return ret; | |
3662 | } | |
3663 | ||
87827111 LZ |
3664 | static int |
3665 | ftrace_graph_release(struct inode *inode, struct file *file) | |
3666 | { | |
3667 | if (file->f_mode & FMODE_READ) | |
3668 | seq_release(inode, file); | |
3669 | return 0; | |
3670 | } | |
3671 | ||
ea4e2bc4 | 3672 | static int |
f9349a8f | 3673 | ftrace_set_func(unsigned long *array, int *idx, char *buffer) |
ea4e2bc4 | 3674 | { |
ea4e2bc4 SR |
3675 | struct dyn_ftrace *rec; |
3676 | struct ftrace_page *pg; | |
f9349a8f | 3677 | int search_len; |
c7c6b1fe | 3678 | int fail = 1; |
f9349a8f FW |
3679 | int type, not; |
3680 | char *search; | |
3681 | bool exists; | |
3682 | int i; | |
ea4e2bc4 | 3683 | |
f9349a8f | 3684 | /* decode regex */ |
3f6fe06d | 3685 | type = filter_parse_regex(buffer, strlen(buffer), &search, ¬); |
c7c6b1fe LZ |
3686 | if (!not && *idx >= FTRACE_GRAPH_MAX_FUNCS) |
3687 | return -EBUSY; | |
f9349a8f FW |
3688 | |
3689 | search_len = strlen(search); | |
3690 | ||
52baf119 | 3691 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
3692 | |
3693 | if (unlikely(ftrace_disabled)) { | |
3694 | mutex_unlock(&ftrace_lock); | |
3695 | return -ENODEV; | |
3696 | } | |
3697 | ||
265c831c SR |
3698 | do_for_each_ftrace_rec(pg, rec) { |
3699 | ||
b9df92d2 | 3700 | if (ftrace_match_record(rec, NULL, search, search_len, type)) { |
c7c6b1fe | 3701 | /* if it is in the array */ |
f9349a8f | 3702 | exists = false; |
c7c6b1fe | 3703 | for (i = 0; i < *idx; i++) { |
f9349a8f FW |
3704 | if (array[i] == rec->ip) { |
3705 | exists = true; | |
265c831c SR |
3706 | break; |
3707 | } | |
c7c6b1fe LZ |
3708 | } |
3709 | ||
3710 | if (!not) { | |
3711 | fail = 0; | |
3712 | if (!exists) { | |
3713 | array[(*idx)++] = rec->ip; | |
3714 | if (*idx >= FTRACE_GRAPH_MAX_FUNCS) | |
3715 | goto out; | |
3716 | } | |
3717 | } else { | |
3718 | if (exists) { | |
3719 | array[i] = array[--(*idx)]; | |
3720 | array[*idx] = 0; | |
3721 | fail = 0; | |
3722 | } | |
3723 | } | |
ea4e2bc4 | 3724 | } |
265c831c | 3725 | } while_for_each_ftrace_rec(); |
c7c6b1fe | 3726 | out: |
52baf119 | 3727 | mutex_unlock(&ftrace_lock); |
ea4e2bc4 | 3728 | |
c7c6b1fe LZ |
3729 | if (fail) |
3730 | return -EINVAL; | |
3731 | ||
3732 | ftrace_graph_filter_enabled = 1; | |
3733 | return 0; | |
ea4e2bc4 SR |
3734 | } |
3735 | ||
3736 | static ssize_t | |
3737 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
3738 | size_t cnt, loff_t *ppos) | |
3739 | { | |
689fd8b6 | 3740 | struct trace_parser parser; |
4ba7978e | 3741 | ssize_t read, ret; |
ea4e2bc4 | 3742 | |
c7c6b1fe | 3743 | if (!cnt) |
ea4e2bc4 SR |
3744 | return 0; |
3745 | ||
3746 | mutex_lock(&graph_lock); | |
3747 | ||
689fd8b6 | 3748 | if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) { |
3749 | ret = -ENOMEM; | |
1eb90f13 | 3750 | goto out_unlock; |
ea4e2bc4 SR |
3751 | } |
3752 | ||
689fd8b6 | 3753 | read = trace_get_user(&parser, ubuf, cnt, ppos); |
ea4e2bc4 | 3754 | |
4ba7978e | 3755 | if (read >= 0 && trace_parser_loaded((&parser))) { |
689fd8b6 | 3756 | parser.buffer[parser.idx] = 0; |
3757 | ||
3758 | /* we allow only one expression at a time */ | |
a4ec5e0c | 3759 | ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, |
689fd8b6 | 3760 | parser.buffer); |
ea4e2bc4 | 3761 | if (ret) |
1eb90f13 | 3762 | goto out_free; |
ea4e2bc4 | 3763 | } |
ea4e2bc4 SR |
3764 | |
3765 | ret = read; | |
1eb90f13 LZ |
3766 | |
3767 | out_free: | |
689fd8b6 | 3768 | trace_parser_put(&parser); |
1eb90f13 | 3769 | out_unlock: |
ea4e2bc4 SR |
3770 | mutex_unlock(&graph_lock); |
3771 | ||
3772 | return ret; | |
3773 | } | |
3774 | ||
3775 | static const struct file_operations ftrace_graph_fops = { | |
87827111 LZ |
3776 | .open = ftrace_graph_open, |
3777 | .read = seq_read, | |
3778 | .write = ftrace_graph_write, | |
3779 | .release = ftrace_graph_release, | |
6038f373 | 3780 | .llseek = seq_lseek, |
ea4e2bc4 SR |
3781 | }; |
3782 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
3783 | ||
df4fc315 | 3784 | static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) |
5072c59f | 3785 | { |
5072c59f | 3786 | |
5452af66 FW |
3787 | trace_create_file("available_filter_functions", 0444, |
3788 | d_tracer, NULL, &ftrace_avail_fops); | |
5072c59f | 3789 | |
647bcd03 SR |
3790 | trace_create_file("enabled_functions", 0444, |
3791 | d_tracer, NULL, &ftrace_enabled_fops); | |
3792 | ||
5452af66 FW |
3793 | trace_create_file("set_ftrace_filter", 0644, d_tracer, |
3794 | NULL, &ftrace_filter_fops); | |
41c52c0d | 3795 | |
5452af66 | 3796 | trace_create_file("set_ftrace_notrace", 0644, d_tracer, |
41c52c0d | 3797 | NULL, &ftrace_notrace_fops); |
ad90c0e3 | 3798 | |
ea4e2bc4 | 3799 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5452af66 | 3800 | trace_create_file("set_graph_function", 0444, d_tracer, |
ea4e2bc4 SR |
3801 | NULL, |
3802 | &ftrace_graph_fops); | |
ea4e2bc4 SR |
3803 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
3804 | ||
5072c59f SR |
3805 | return 0; |
3806 | } | |
3807 | ||
9fd49328 | 3808 | static int ftrace_cmp_ips(const void *a, const void *b) |
68950619 | 3809 | { |
9fd49328 SR |
3810 | const unsigned long *ipa = a; |
3811 | const unsigned long *ipb = b; | |
68950619 | 3812 | |
9fd49328 SR |
3813 | if (*ipa > *ipb) |
3814 | return 1; | |
3815 | if (*ipa < *ipb) | |
3816 | return -1; | |
3817 | return 0; | |
3818 | } | |
3819 | ||
3820 | static void ftrace_swap_ips(void *a, void *b, int size) | |
3821 | { | |
3822 | unsigned long *ipa = a; | |
3823 | unsigned long *ipb = b; | |
3824 | unsigned long t; | |
3825 | ||
3826 | t = *ipa; | |
3827 | *ipa = *ipb; | |
3828 | *ipb = t; | |
68950619 SR |
3829 | } |
3830 | ||
5cb084bb | 3831 | static int ftrace_process_locs(struct module *mod, |
31e88909 | 3832 | unsigned long *start, |
68bf21aa SR |
3833 | unsigned long *end) |
3834 | { | |
706c81f8 | 3835 | struct ftrace_page *start_pg; |
a7900875 | 3836 | struct ftrace_page *pg; |
706c81f8 | 3837 | struct dyn_ftrace *rec; |
a7900875 | 3838 | unsigned long count; |
68bf21aa SR |
3839 | unsigned long *p; |
3840 | unsigned long addr; | |
4376cac6 | 3841 | unsigned long flags = 0; /* Shut up gcc */ |
a7900875 SR |
3842 | int ret = -ENOMEM; |
3843 | ||
3844 | count = end - start; | |
3845 | ||
3846 | if (!count) | |
3847 | return 0; | |
3848 | ||
9fd49328 SR |
3849 | sort(start, count, sizeof(*start), |
3850 | ftrace_cmp_ips, ftrace_swap_ips); | |
3851 | ||
706c81f8 SR |
3852 | start_pg = ftrace_allocate_pages(count); |
3853 | if (!start_pg) | |
a7900875 | 3854 | return -ENOMEM; |
68bf21aa | 3855 | |
e6ea44e9 | 3856 | mutex_lock(&ftrace_lock); |
a7900875 | 3857 | |
32082309 SR |
3858 | /* |
3859 | * Core and each module needs their own pages, as | |
3860 | * modules will free them when they are removed. | |
3861 | * Force a new page to be allocated for modules. | |
3862 | */ | |
a7900875 SR |
3863 | if (!mod) { |
3864 | WARN_ON(ftrace_pages || ftrace_pages_start); | |
3865 | /* First initialization */ | |
706c81f8 | 3866 | ftrace_pages = ftrace_pages_start = start_pg; |
a7900875 | 3867 | } else { |
32082309 | 3868 | if (!ftrace_pages) |
a7900875 | 3869 | goto out; |
32082309 | 3870 | |
a7900875 SR |
3871 | if (WARN_ON(ftrace_pages->next)) { |
3872 | /* Hmm, we have free pages? */ | |
3873 | while (ftrace_pages->next) | |
3874 | ftrace_pages = ftrace_pages->next; | |
32082309 | 3875 | } |
a7900875 | 3876 | |
706c81f8 | 3877 | ftrace_pages->next = start_pg; |
32082309 SR |
3878 | } |
3879 | ||
68bf21aa | 3880 | p = start; |
706c81f8 | 3881 | pg = start_pg; |
68bf21aa SR |
3882 | while (p < end) { |
3883 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
3884 | /* |
3885 | * Some architecture linkers will pad between | |
3886 | * the different mcount_loc sections of different | |
3887 | * object files to satisfy alignments. | |
3888 | * Skip any NULL pointers. | |
3889 | */ | |
3890 | if (!addr) | |
3891 | continue; | |
706c81f8 SR |
3892 | |
3893 | if (pg->index == pg->size) { | |
3894 | /* We should have allocated enough */ | |
3895 | if (WARN_ON(!pg->next)) | |
3896 | break; | |
3897 | pg = pg->next; | |
3898 | } | |
3899 | ||
3900 | rec = &pg->records[pg->index++]; | |
3901 | rec->ip = addr; | |
68bf21aa SR |
3902 | } |
3903 | ||
706c81f8 SR |
3904 | /* We should have used all pages */ |
3905 | WARN_ON(pg->next); | |
3906 | ||
3907 | /* Assign the last page to ftrace_pages */ | |
3908 | ftrace_pages = pg; | |
3909 | ||
85ae32ae | 3910 | /* These new locations need to be initialized */ |
706c81f8 | 3911 | ftrace_new_pgs = start_pg; |
85ae32ae | 3912 | |
a4f18ed1 | 3913 | /* |
4376cac6 SR |
3914 | * We only need to disable interrupts on start up |
3915 | * because we are modifying code that an interrupt | |
3916 | * may execute, and the modification is not atomic. | |
3917 | * But for modules, nothing runs the code we modify | |
3918 | * until we are finished with it, and there's no | |
3919 | * reason to cause large interrupt latencies while we do it. | |
a4f18ed1 | 3920 | */ |
4376cac6 SR |
3921 | if (!mod) |
3922 | local_irq_save(flags); | |
31e88909 | 3923 | ftrace_update_code(mod); |
4376cac6 SR |
3924 | if (!mod) |
3925 | local_irq_restore(flags); | |
a7900875 SR |
3926 | ret = 0; |
3927 | out: | |
e6ea44e9 | 3928 | mutex_unlock(&ftrace_lock); |
68bf21aa | 3929 | |
a7900875 | 3930 | return ret; |
68bf21aa SR |
3931 | } |
3932 | ||
93eb677d | 3933 | #ifdef CONFIG_MODULES |
32082309 SR |
3934 | |
3935 | #define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next) | |
3936 | ||
e7247a15 | 3937 | void ftrace_release_mod(struct module *mod) |
93eb677d SR |
3938 | { |
3939 | struct dyn_ftrace *rec; | |
32082309 | 3940 | struct ftrace_page **last_pg; |
93eb677d | 3941 | struct ftrace_page *pg; |
a7900875 | 3942 | int order; |
93eb677d | 3943 | |
45a4a237 SR |
3944 | mutex_lock(&ftrace_lock); |
3945 | ||
e7247a15 | 3946 | if (ftrace_disabled) |
45a4a237 | 3947 | goto out_unlock; |
93eb677d | 3948 | |
32082309 SR |
3949 | /* |
3950 | * Each module has its own ftrace_pages, remove | |
3951 | * them from the list. | |
3952 | */ | |
3953 | last_pg = &ftrace_pages_start; | |
3954 | for (pg = ftrace_pages_start; pg; pg = *last_pg) { | |
3955 | rec = &pg->records[0]; | |
e7247a15 | 3956 | if (within_module_core(rec->ip, mod)) { |
93eb677d | 3957 | /* |
32082309 SR |
3958 | * As core pages are first, the first |
3959 | * page should never be a module page. | |
93eb677d | 3960 | */ |
32082309 SR |
3961 | if (WARN_ON(pg == ftrace_pages_start)) |
3962 | goto out_unlock; | |
3963 | ||
3964 | /* Check if we are deleting the last page */ | |
3965 | if (pg == ftrace_pages) | |
3966 | ftrace_pages = next_to_ftrace_page(last_pg); | |
3967 | ||
3968 | *last_pg = pg->next; | |
a7900875 SR |
3969 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); |
3970 | free_pages((unsigned long)pg->records, order); | |
3971 | kfree(pg); | |
32082309 SR |
3972 | } else |
3973 | last_pg = &pg->next; | |
3974 | } | |
45a4a237 | 3975 | out_unlock: |
93eb677d SR |
3976 | mutex_unlock(&ftrace_lock); |
3977 | } | |
3978 | ||
3979 | static void ftrace_init_module(struct module *mod, | |
3980 | unsigned long *start, unsigned long *end) | |
90d595fe | 3981 | { |
00fd61ae | 3982 | if (ftrace_disabled || start == end) |
fed1939c | 3983 | return; |
5cb084bb | 3984 | ftrace_process_locs(mod, start, end); |
90d595fe SR |
3985 | } |
3986 | ||
93eb677d SR |
3987 | static int ftrace_module_notify(struct notifier_block *self, |
3988 | unsigned long val, void *data) | |
3989 | { | |
3990 | struct module *mod = data; | |
3991 | ||
3992 | switch (val) { | |
3993 | case MODULE_STATE_COMING: | |
3994 | ftrace_init_module(mod, mod->ftrace_callsites, | |
3995 | mod->ftrace_callsites + | |
3996 | mod->num_ftrace_callsites); | |
3997 | break; | |
3998 | case MODULE_STATE_GOING: | |
e7247a15 | 3999 | ftrace_release_mod(mod); |
93eb677d SR |
4000 | break; |
4001 | } | |
4002 | ||
4003 | return 0; | |
4004 | } | |
4005 | #else | |
4006 | static int ftrace_module_notify(struct notifier_block *self, | |
4007 | unsigned long val, void *data) | |
4008 | { | |
4009 | return 0; | |
4010 | } | |
4011 | #endif /* CONFIG_MODULES */ | |
4012 | ||
4013 | struct notifier_block ftrace_module_nb = { | |
4014 | .notifier_call = ftrace_module_notify, | |
c1bf08ac | 4015 | .priority = INT_MAX, /* Run before anything that can use kprobes */ |
93eb677d SR |
4016 | }; |
4017 | ||
68bf21aa SR |
4018 | extern unsigned long __start_mcount_loc[]; |
4019 | extern unsigned long __stop_mcount_loc[]; | |
4020 | ||
4021 | void __init ftrace_init(void) | |
4022 | { | |
4023 | unsigned long count, addr, flags; | |
4024 | int ret; | |
4025 | ||
4026 | /* Keep the ftrace pointer to the stub */ | |
4027 | addr = (unsigned long)ftrace_stub; | |
4028 | ||
4029 | local_irq_save(flags); | |
4030 | ftrace_dyn_arch_init(&addr); | |
4031 | local_irq_restore(flags); | |
4032 | ||
4033 | /* ftrace_dyn_arch_init places the return code in addr */ | |
4034 | if (addr) | |
4035 | goto failed; | |
4036 | ||
4037 | count = __stop_mcount_loc - __start_mcount_loc; | |
4038 | ||
4039 | ret = ftrace_dyn_table_alloc(count); | |
4040 | if (ret) | |
4041 | goto failed; | |
4042 | ||
4043 | last_ftrace_enabled = ftrace_enabled = 1; | |
4044 | ||
5cb084bb | 4045 | ret = ftrace_process_locs(NULL, |
31e88909 | 4046 | __start_mcount_loc, |
68bf21aa SR |
4047 | __stop_mcount_loc); |
4048 | ||
93eb677d | 4049 | ret = register_module_notifier(&ftrace_module_nb); |
24ed0c4b | 4050 | if (ret) |
93eb677d SR |
4051 | pr_warning("Failed to register trace ftrace module notifier\n"); |
4052 | ||
2af15d6a SR |
4053 | set_ftrace_early_filters(); |
4054 | ||
68bf21aa SR |
4055 | return; |
4056 | failed: | |
4057 | ftrace_disabled = 1; | |
4058 | } | |
68bf21aa | 4059 | |
3d083395 | 4060 | #else |
0b6e4d56 | 4061 | |
2b499381 | 4062 | static struct ftrace_ops global_ops = { |
bd69c30b | 4063 | .func = ftrace_stub, |
4740974a | 4064 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
bd69c30b SR |
4065 | }; |
4066 | ||
0b6e4d56 FW |
4067 | static int __init ftrace_nodyn_init(void) |
4068 | { | |
4069 | ftrace_enabled = 1; | |
4070 | return 0; | |
4071 | } | |
6f415672 | 4072 | core_initcall(ftrace_nodyn_init); |
0b6e4d56 | 4073 | |
df4fc315 SR |
4074 | static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } |
4075 | static inline void ftrace_startup_enable(int command) { } | |
5a45cfe1 | 4076 | /* Keep as macros so we do not need to define the commands */ |
3b6cfdb1 SR |
4077 | # define ftrace_startup(ops, command) \ |
4078 | ({ \ | |
4079 | (ops)->flags |= FTRACE_OPS_FL_ENABLED; \ | |
4080 | 0; \ | |
4081 | }) | |
bd69c30b | 4082 | # define ftrace_shutdown(ops, command) do { } while (0) |
c7aafc54 IM |
4083 | # define ftrace_startup_sysctl() do { } while (0) |
4084 | # define ftrace_shutdown_sysctl() do { } while (0) | |
b848914c SR |
4085 | |
4086 | static inline int | |
4087 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip) | |
4088 | { | |
4089 | return 1; | |
4090 | } | |
4091 | ||
3d083395 SR |
4092 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
4093 | ||
e248491a | 4094 | static void |
2f5f6ad9 | 4095 | ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 4096 | struct ftrace_ops *op, struct pt_regs *regs) |
e248491a | 4097 | { |
e248491a JO |
4098 | if (unlikely(trace_recursion_test(TRACE_CONTROL_BIT))) |
4099 | return; | |
4100 | ||
4101 | /* | |
4102 | * Some of the ops may be dynamically allocated, | |
4103 | * they must be freed after a synchronize_sched(). | |
4104 | */ | |
4105 | preempt_disable_notrace(); | |
4106 | trace_recursion_set(TRACE_CONTROL_BIT); | |
4107 | op = rcu_dereference_raw(ftrace_control_list); | |
4108 | while (op != &ftrace_list_end) { | |
4109 | if (!ftrace_function_local_disabled(op) && | |
4110 | ftrace_ops_test(op, ip)) | |
a1e2e31d | 4111 | op->func(ip, parent_ip, op, regs); |
e248491a JO |
4112 | |
4113 | op = rcu_dereference_raw(op->next); | |
4114 | }; | |
4115 | trace_recursion_clear(TRACE_CONTROL_BIT); | |
4116 | preempt_enable_notrace(); | |
4117 | } | |
4118 | ||
4119 | static struct ftrace_ops control_ops = { | |
4120 | .func = ftrace_ops_control_func, | |
4740974a | 4121 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
e248491a JO |
4122 | }; |
4123 | ||
2f5f6ad9 SR |
4124 | static inline void |
4125 | __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 4126 | struct ftrace_ops *ignored, struct pt_regs *regs) |
b848914c | 4127 | { |
cdbe61bf | 4128 | struct ftrace_ops *op; |
b848914c | 4129 | |
ccf3672d SR |
4130 | if (function_trace_stop) |
4131 | return; | |
4132 | ||
b1cff0ad SR |
4133 | if (unlikely(trace_recursion_test(TRACE_INTERNAL_BIT))) |
4134 | return; | |
4135 | ||
4136 | trace_recursion_set(TRACE_INTERNAL_BIT); | |
cdbe61bf SR |
4137 | /* |
4138 | * Some of the ops may be dynamically allocated, | |
4139 | * they must be freed after a synchronize_sched(). | |
4140 | */ | |
4141 | preempt_disable_notrace(); | |
4142 | op = rcu_dereference_raw(ftrace_ops_list); | |
b848914c SR |
4143 | while (op != &ftrace_list_end) { |
4144 | if (ftrace_ops_test(op, ip)) | |
a1e2e31d | 4145 | op->func(ip, parent_ip, op, regs); |
b848914c SR |
4146 | op = rcu_dereference_raw(op->next); |
4147 | }; | |
cdbe61bf | 4148 | preempt_enable_notrace(); |
b1cff0ad | 4149 | trace_recursion_clear(TRACE_INTERNAL_BIT); |
b848914c SR |
4150 | } |
4151 | ||
2f5f6ad9 SR |
4152 | /* |
4153 | * Some archs only support passing ip and parent_ip. Even though | |
4154 | * the list function ignores the op parameter, we do not want any | |
4155 | * C side effects, where a function is called without the caller | |
4156 | * sending a third parameter. | |
a1e2e31d SR |
4157 | * Archs are to support both the regs and ftrace_ops at the same time. |
4158 | * If they support ftrace_ops, it is assumed they support regs. | |
4159 | * If call backs want to use regs, they must either check for regs | |
06aeaaea MH |
4160 | * being NULL, or CONFIG_DYNAMIC_FTRACE_WITH_REGS. |
4161 | * Note, CONFIG_DYNAMIC_FTRACE_WITH_REGS expects a full regs to be saved. | |
a1e2e31d SR |
4162 | * An architecture can pass partial regs with ftrace_ops and still |
4163 | * set the ARCH_SUPPORT_FTARCE_OPS. | |
2f5f6ad9 SR |
4164 | */ |
4165 | #if ARCH_SUPPORTS_FTRACE_OPS | |
4166 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 4167 | struct ftrace_ops *op, struct pt_regs *regs) |
2f5f6ad9 | 4168 | { |
a1e2e31d | 4169 | __ftrace_ops_list_func(ip, parent_ip, NULL, regs); |
2f5f6ad9 SR |
4170 | } |
4171 | #else | |
4172 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip) | |
4173 | { | |
a1e2e31d | 4174 | __ftrace_ops_list_func(ip, parent_ip, NULL, NULL); |
2f5f6ad9 SR |
4175 | } |
4176 | #endif | |
4177 | ||
e32d8956 | 4178 | static void clear_ftrace_swapper(void) |
978f3a45 SR |
4179 | { |
4180 | struct task_struct *p; | |
e32d8956 | 4181 | int cpu; |
978f3a45 | 4182 | |
e32d8956 SR |
4183 | get_online_cpus(); |
4184 | for_each_online_cpu(cpu) { | |
4185 | p = idle_task(cpu); | |
978f3a45 | 4186 | clear_tsk_trace_trace(p); |
e32d8956 SR |
4187 | } |
4188 | put_online_cpus(); | |
4189 | } | |
978f3a45 | 4190 | |
e32d8956 SR |
4191 | static void set_ftrace_swapper(void) |
4192 | { | |
4193 | struct task_struct *p; | |
4194 | int cpu; | |
4195 | ||
4196 | get_online_cpus(); | |
4197 | for_each_online_cpu(cpu) { | |
4198 | p = idle_task(cpu); | |
4199 | set_tsk_trace_trace(p); | |
4200 | } | |
4201 | put_online_cpus(); | |
978f3a45 SR |
4202 | } |
4203 | ||
e32d8956 SR |
4204 | static void clear_ftrace_pid(struct pid *pid) |
4205 | { | |
4206 | struct task_struct *p; | |
4207 | ||
229c4ef8 | 4208 | rcu_read_lock(); |
e32d8956 SR |
4209 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
4210 | clear_tsk_trace_trace(p); | |
4211 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 ON |
4212 | rcu_read_unlock(); |
4213 | ||
e32d8956 SR |
4214 | put_pid(pid); |
4215 | } | |
4216 | ||
4217 | static void set_ftrace_pid(struct pid *pid) | |
978f3a45 SR |
4218 | { |
4219 | struct task_struct *p; | |
4220 | ||
229c4ef8 | 4221 | rcu_read_lock(); |
978f3a45 SR |
4222 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
4223 | set_tsk_trace_trace(p); | |
4224 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 | 4225 | rcu_read_unlock(); |
978f3a45 SR |
4226 | } |
4227 | ||
756d17ee | 4228 | static void clear_ftrace_pid_task(struct pid *pid) |
e32d8956 | 4229 | { |
756d17ee | 4230 | if (pid == ftrace_swapper_pid) |
e32d8956 SR |
4231 | clear_ftrace_swapper(); |
4232 | else | |
756d17ee | 4233 | clear_ftrace_pid(pid); |
e32d8956 SR |
4234 | } |
4235 | ||
4236 | static void set_ftrace_pid_task(struct pid *pid) | |
4237 | { | |
4238 | if (pid == ftrace_swapper_pid) | |
4239 | set_ftrace_swapper(); | |
4240 | else | |
4241 | set_ftrace_pid(pid); | |
4242 | } | |
4243 | ||
756d17ee | 4244 | static int ftrace_pid_add(int p) |
df4fc315 | 4245 | { |
978f3a45 | 4246 | struct pid *pid; |
756d17ee | 4247 | struct ftrace_pid *fpid; |
4248 | int ret = -EINVAL; | |
df4fc315 | 4249 | |
756d17ee | 4250 | mutex_lock(&ftrace_lock); |
df4fc315 | 4251 | |
756d17ee | 4252 | if (!p) |
4253 | pid = ftrace_swapper_pid; | |
4254 | else | |
4255 | pid = find_get_pid(p); | |
df4fc315 | 4256 | |
756d17ee | 4257 | if (!pid) |
4258 | goto out; | |
df4fc315 | 4259 | |
756d17ee | 4260 | ret = 0; |
df4fc315 | 4261 | |
756d17ee | 4262 | list_for_each_entry(fpid, &ftrace_pids, list) |
4263 | if (fpid->pid == pid) | |
4264 | goto out_put; | |
978f3a45 | 4265 | |
756d17ee | 4266 | ret = -ENOMEM; |
df4fc315 | 4267 | |
756d17ee | 4268 | fpid = kmalloc(sizeof(*fpid), GFP_KERNEL); |
4269 | if (!fpid) | |
4270 | goto out_put; | |
df4fc315 | 4271 | |
756d17ee | 4272 | list_add(&fpid->list, &ftrace_pids); |
4273 | fpid->pid = pid; | |
0ef8cde5 | 4274 | |
756d17ee | 4275 | set_ftrace_pid_task(pid); |
978f3a45 | 4276 | |
756d17ee | 4277 | ftrace_update_pid_func(); |
4278 | ftrace_startup_enable(0); | |
4279 | ||
4280 | mutex_unlock(&ftrace_lock); | |
4281 | return 0; | |
4282 | ||
4283 | out_put: | |
4284 | if (pid != ftrace_swapper_pid) | |
4285 | put_pid(pid); | |
978f3a45 | 4286 | |
756d17ee | 4287 | out: |
4288 | mutex_unlock(&ftrace_lock); | |
4289 | return ret; | |
4290 | } | |
4291 | ||
4292 | static void ftrace_pid_reset(void) | |
4293 | { | |
4294 | struct ftrace_pid *fpid, *safe; | |
978f3a45 | 4295 | |
756d17ee | 4296 | mutex_lock(&ftrace_lock); |
4297 | list_for_each_entry_safe(fpid, safe, &ftrace_pids, list) { | |
4298 | struct pid *pid = fpid->pid; | |
4299 | ||
4300 | clear_ftrace_pid_task(pid); | |
4301 | ||
4302 | list_del(&fpid->list); | |
4303 | kfree(fpid); | |
df4fc315 SR |
4304 | } |
4305 | ||
df4fc315 SR |
4306 | ftrace_update_pid_func(); |
4307 | ftrace_startup_enable(0); | |
4308 | ||
e6ea44e9 | 4309 | mutex_unlock(&ftrace_lock); |
756d17ee | 4310 | } |
df4fc315 | 4311 | |
756d17ee | 4312 | static void *fpid_start(struct seq_file *m, loff_t *pos) |
4313 | { | |
4314 | mutex_lock(&ftrace_lock); | |
4315 | ||
4316 | if (list_empty(&ftrace_pids) && (!*pos)) | |
4317 | return (void *) 1; | |
4318 | ||
4319 | return seq_list_start(&ftrace_pids, *pos); | |
4320 | } | |
4321 | ||
4322 | static void *fpid_next(struct seq_file *m, void *v, loff_t *pos) | |
4323 | { | |
4324 | if (v == (void *)1) | |
4325 | return NULL; | |
4326 | ||
4327 | return seq_list_next(v, &ftrace_pids, pos); | |
4328 | } | |
4329 | ||
4330 | static void fpid_stop(struct seq_file *m, void *p) | |
4331 | { | |
4332 | mutex_unlock(&ftrace_lock); | |
4333 | } | |
4334 | ||
4335 | static int fpid_show(struct seq_file *m, void *v) | |
4336 | { | |
4337 | const struct ftrace_pid *fpid = list_entry(v, struct ftrace_pid, list); | |
4338 | ||
4339 | if (v == (void *)1) { | |
4340 | seq_printf(m, "no pid\n"); | |
4341 | return 0; | |
4342 | } | |
4343 | ||
4344 | if (fpid->pid == ftrace_swapper_pid) | |
4345 | seq_printf(m, "swapper tasks\n"); | |
4346 | else | |
4347 | seq_printf(m, "%u\n", pid_vnr(fpid->pid)); | |
4348 | ||
4349 | return 0; | |
4350 | } | |
4351 | ||
4352 | static const struct seq_operations ftrace_pid_sops = { | |
4353 | .start = fpid_start, | |
4354 | .next = fpid_next, | |
4355 | .stop = fpid_stop, | |
4356 | .show = fpid_show, | |
4357 | }; | |
4358 | ||
4359 | static int | |
4360 | ftrace_pid_open(struct inode *inode, struct file *file) | |
4361 | { | |
4362 | int ret = 0; | |
4363 | ||
4364 | if ((file->f_mode & FMODE_WRITE) && | |
4365 | (file->f_flags & O_TRUNC)) | |
4366 | ftrace_pid_reset(); | |
4367 | ||
4368 | if (file->f_mode & FMODE_READ) | |
4369 | ret = seq_open(file, &ftrace_pid_sops); | |
4370 | ||
4371 | return ret; | |
4372 | } | |
4373 | ||
df4fc315 SR |
4374 | static ssize_t |
4375 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
4376 | size_t cnt, loff_t *ppos) | |
4377 | { | |
457dc928 | 4378 | char buf[64], *tmp; |
df4fc315 SR |
4379 | long val; |
4380 | int ret; | |
4381 | ||
4382 | if (cnt >= sizeof(buf)) | |
4383 | return -EINVAL; | |
4384 | ||
4385 | if (copy_from_user(&buf, ubuf, cnt)) | |
4386 | return -EFAULT; | |
4387 | ||
4388 | buf[cnt] = 0; | |
4389 | ||
756d17ee | 4390 | /* |
4391 | * Allow "echo > set_ftrace_pid" or "echo -n '' > set_ftrace_pid" | |
4392 | * to clean the filter quietly. | |
4393 | */ | |
457dc928 IM |
4394 | tmp = strstrip(buf); |
4395 | if (strlen(tmp) == 0) | |
756d17ee | 4396 | return 1; |
4397 | ||
bcd83ea6 | 4398 | ret = kstrtol(tmp, 10, &val); |
df4fc315 SR |
4399 | if (ret < 0) |
4400 | return ret; | |
4401 | ||
756d17ee | 4402 | ret = ftrace_pid_add(val); |
df4fc315 | 4403 | |
756d17ee | 4404 | return ret ? ret : cnt; |
4405 | } | |
df4fc315 | 4406 | |
756d17ee | 4407 | static int |
4408 | ftrace_pid_release(struct inode *inode, struct file *file) | |
4409 | { | |
4410 | if (file->f_mode & FMODE_READ) | |
4411 | seq_release(inode, file); | |
df4fc315 | 4412 | |
756d17ee | 4413 | return 0; |
df4fc315 SR |
4414 | } |
4415 | ||
5e2336a0 | 4416 | static const struct file_operations ftrace_pid_fops = { |
756d17ee | 4417 | .open = ftrace_pid_open, |
4418 | .write = ftrace_pid_write, | |
4419 | .read = seq_read, | |
4420 | .llseek = seq_lseek, | |
4421 | .release = ftrace_pid_release, | |
df4fc315 SR |
4422 | }; |
4423 | ||
4424 | static __init int ftrace_init_debugfs(void) | |
4425 | { | |
4426 | struct dentry *d_tracer; | |
df4fc315 SR |
4427 | |
4428 | d_tracer = tracing_init_dentry(); | |
4429 | if (!d_tracer) | |
4430 | return 0; | |
4431 | ||
4432 | ftrace_init_dyn_debugfs(d_tracer); | |
4433 | ||
5452af66 FW |
4434 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
4435 | NULL, &ftrace_pid_fops); | |
493762fc SR |
4436 | |
4437 | ftrace_profile_debugfs(d_tracer); | |
4438 | ||
df4fc315 SR |
4439 | return 0; |
4440 | } | |
df4fc315 SR |
4441 | fs_initcall(ftrace_init_debugfs); |
4442 | ||
a2bb6a3d | 4443 | /** |
81adbdc0 | 4444 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
4445 | * |
4446 | * This function should be used by panic code. It stops ftrace | |
4447 | * but in a not so nice way. If you need to simply kill ftrace | |
4448 | * from a non-atomic section, use ftrace_kill. | |
4449 | */ | |
81adbdc0 | 4450 | void ftrace_kill(void) |
a2bb6a3d SR |
4451 | { |
4452 | ftrace_disabled = 1; | |
4453 | ftrace_enabled = 0; | |
a2bb6a3d SR |
4454 | clear_ftrace_function(); |
4455 | } | |
4456 | ||
e0a413f6 SR |
4457 | /** |
4458 | * Test if ftrace is dead or not. | |
4459 | */ | |
4460 | int ftrace_is_dead(void) | |
4461 | { | |
4462 | return ftrace_disabled; | |
4463 | } | |
4464 | ||
16444a8a | 4465 | /** |
3d083395 SR |
4466 | * register_ftrace_function - register a function for profiling |
4467 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 4468 | * |
3d083395 SR |
4469 | * Register a function to be called by all functions in the |
4470 | * kernel. | |
4471 | * | |
4472 | * Note: @ops->func and all the functions it calls must be labeled | |
4473 | * with "notrace", otherwise it will go into a | |
4474 | * recursive loop. | |
16444a8a | 4475 | */ |
3d083395 | 4476 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 4477 | { |
45a4a237 | 4478 | int ret = -1; |
4eebcc81 | 4479 | |
e6ea44e9 | 4480 | mutex_lock(&ftrace_lock); |
e7d3737e | 4481 | |
b0fc494f | 4482 | ret = __register_ftrace_function(ops); |
b848914c | 4483 | if (!ret) |
a1cd6173 | 4484 | ret = ftrace_startup(ops, 0); |
b848914c | 4485 | |
e6ea44e9 | 4486 | mutex_unlock(&ftrace_lock); |
8d240dd8 | 4487 | |
b0fc494f | 4488 | return ret; |
3d083395 | 4489 | } |
cdbe61bf | 4490 | EXPORT_SYMBOL_GPL(register_ftrace_function); |
3d083395 SR |
4491 | |
4492 | /** | |
32632920 | 4493 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
4494 | * @ops - ops structure that holds the function to unregister |
4495 | * | |
4496 | * Unregister a function that was added to be called by ftrace profiling. | |
4497 | */ | |
4498 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
4499 | { | |
4500 | int ret; | |
4501 | ||
e6ea44e9 | 4502 | mutex_lock(&ftrace_lock); |
3d083395 | 4503 | ret = __unregister_ftrace_function(ops); |
b848914c SR |
4504 | if (!ret) |
4505 | ftrace_shutdown(ops, 0); | |
e6ea44e9 | 4506 | mutex_unlock(&ftrace_lock); |
b0fc494f SR |
4507 | |
4508 | return ret; | |
4509 | } | |
cdbe61bf | 4510 | EXPORT_SYMBOL_GPL(unregister_ftrace_function); |
b0fc494f | 4511 | |
e309b41d | 4512 | int |
b0fc494f | 4513 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
8d65af78 | 4514 | void __user *buffer, size_t *lenp, |
b0fc494f SR |
4515 | loff_t *ppos) |
4516 | { | |
45a4a237 | 4517 | int ret = -ENODEV; |
4eebcc81 | 4518 | |
e6ea44e9 | 4519 | mutex_lock(&ftrace_lock); |
b0fc494f | 4520 | |
45a4a237 SR |
4521 | if (unlikely(ftrace_disabled)) |
4522 | goto out; | |
4523 | ||
4524 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
b0fc494f | 4525 | |
a32c7765 | 4526 | if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) |
b0fc494f SR |
4527 | goto out; |
4528 | ||
a32c7765 | 4529 | last_ftrace_enabled = !!ftrace_enabled; |
b0fc494f SR |
4530 | |
4531 | if (ftrace_enabled) { | |
4532 | ||
4533 | ftrace_startup_sysctl(); | |
4534 | ||
4535 | /* we are starting ftrace again */ | |
b848914c SR |
4536 | if (ftrace_ops_list != &ftrace_list_end) { |
4537 | if (ftrace_ops_list->next == &ftrace_list_end) | |
4538 | ftrace_trace_function = ftrace_ops_list->func; | |
b0fc494f | 4539 | else |
b848914c | 4540 | ftrace_trace_function = ftrace_ops_list_func; |
b0fc494f SR |
4541 | } |
4542 | ||
4543 | } else { | |
4544 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
4545 | ftrace_trace_function = ftrace_stub; | |
4546 | ||
4547 | ftrace_shutdown_sysctl(); | |
4548 | } | |
4549 | ||
4550 | out: | |
e6ea44e9 | 4551 | mutex_unlock(&ftrace_lock); |
3d083395 | 4552 | return ret; |
16444a8a | 4553 | } |
f17845e5 | 4554 | |
fb52607a | 4555 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 4556 | |
597af815 | 4557 | static int ftrace_graph_active; |
4a2b8dda | 4558 | static struct notifier_block ftrace_suspend_notifier; |
e7d3737e | 4559 | |
e49dc19c SR |
4560 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
4561 | { | |
4562 | return 0; | |
4563 | } | |
4564 | ||
287b6e68 FW |
4565 | /* The callbacks that hook a function */ |
4566 | trace_func_graph_ret_t ftrace_graph_return = | |
4567 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 4568 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
4569 | |
4570 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
4571 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
4572 | { | |
4573 | int i; | |
4574 | int ret = 0; | |
4575 | unsigned long flags; | |
4576 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; | |
4577 | struct task_struct *g, *t; | |
4578 | ||
4579 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
4580 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
4581 | * sizeof(struct ftrace_ret_stack), | |
4582 | GFP_KERNEL); | |
4583 | if (!ret_stack_list[i]) { | |
4584 | start = 0; | |
4585 | end = i; | |
4586 | ret = -ENOMEM; | |
4587 | goto free; | |
4588 | } | |
4589 | } | |
4590 | ||
4591 | read_lock_irqsave(&tasklist_lock, flags); | |
4592 | do_each_thread(g, t) { | |
4593 | if (start == end) { | |
4594 | ret = -EAGAIN; | |
4595 | goto unlock; | |
4596 | } | |
4597 | ||
4598 | if (t->ret_stack == NULL) { | |
380c4b14 | 4599 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 | 4600 | atomic_set(&t->trace_overrun, 0); |
26c01624 SR |
4601 | t->curr_ret_stack = -1; |
4602 | /* Make sure the tasks see the -1 first: */ | |
4603 | smp_wmb(); | |
4604 | t->ret_stack = ret_stack_list[start++]; | |
f201ae23 FW |
4605 | } |
4606 | } while_each_thread(g, t); | |
4607 | ||
4608 | unlock: | |
4609 | read_unlock_irqrestore(&tasklist_lock, flags); | |
4610 | free: | |
4611 | for (i = start; i < end; i++) | |
4612 | kfree(ret_stack_list[i]); | |
4613 | return ret; | |
4614 | } | |
4615 | ||
8aef2d28 | 4616 | static void |
38516ab5 SR |
4617 | ftrace_graph_probe_sched_switch(void *ignore, |
4618 | struct task_struct *prev, struct task_struct *next) | |
8aef2d28 SR |
4619 | { |
4620 | unsigned long long timestamp; | |
4621 | int index; | |
4622 | ||
be6f164a SR |
4623 | /* |
4624 | * Does the user want to count the time a function was asleep. | |
4625 | * If so, do not update the time stamps. | |
4626 | */ | |
4627 | if (trace_flags & TRACE_ITER_SLEEP_TIME) | |
4628 | return; | |
4629 | ||
8aef2d28 SR |
4630 | timestamp = trace_clock_local(); |
4631 | ||
4632 | prev->ftrace_timestamp = timestamp; | |
4633 | ||
4634 | /* only process tasks that we timestamped */ | |
4635 | if (!next->ftrace_timestamp) | |
4636 | return; | |
4637 | ||
4638 | /* | |
4639 | * Update all the counters in next to make up for the | |
4640 | * time next was sleeping. | |
4641 | */ | |
4642 | timestamp -= next->ftrace_timestamp; | |
4643 | ||
4644 | for (index = next->curr_ret_stack; index >= 0; index--) | |
4645 | next->ret_stack[index].calltime += timestamp; | |
4646 | } | |
4647 | ||
f201ae23 | 4648 | /* Allocate a return stack for each task */ |
fb52607a | 4649 | static int start_graph_tracing(void) |
f201ae23 FW |
4650 | { |
4651 | struct ftrace_ret_stack **ret_stack_list; | |
5b058bcd | 4652 | int ret, cpu; |
f201ae23 FW |
4653 | |
4654 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
4655 | sizeof(struct ftrace_ret_stack *), | |
4656 | GFP_KERNEL); | |
4657 | ||
4658 | if (!ret_stack_list) | |
4659 | return -ENOMEM; | |
4660 | ||
5b058bcd | 4661 | /* The cpu_boot init_task->ret_stack will never be freed */ |
179c498a SR |
4662 | for_each_online_cpu(cpu) { |
4663 | if (!idle_task(cpu)->ret_stack) | |
868baf07 | 4664 | ftrace_graph_init_idle_task(idle_task(cpu), cpu); |
179c498a | 4665 | } |
5b058bcd | 4666 | |
f201ae23 FW |
4667 | do { |
4668 | ret = alloc_retstack_tasklist(ret_stack_list); | |
4669 | } while (ret == -EAGAIN); | |
4670 | ||
8aef2d28 | 4671 | if (!ret) { |
38516ab5 | 4672 | ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
8aef2d28 SR |
4673 | if (ret) |
4674 | pr_info("ftrace_graph: Couldn't activate tracepoint" | |
4675 | " probe to kernel_sched_switch\n"); | |
4676 | } | |
4677 | ||
f201ae23 FW |
4678 | kfree(ret_stack_list); |
4679 | return ret; | |
4680 | } | |
4681 | ||
4a2b8dda FW |
4682 | /* |
4683 | * Hibernation protection. | |
4684 | * The state of the current task is too much unstable during | |
4685 | * suspend/restore to disk. We want to protect against that. | |
4686 | */ | |
4687 | static int | |
4688 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, | |
4689 | void *unused) | |
4690 | { | |
4691 | switch (state) { | |
4692 | case PM_HIBERNATION_PREPARE: | |
4693 | pause_graph_tracing(); | |
4694 | break; | |
4695 | ||
4696 | case PM_POST_HIBERNATION: | |
4697 | unpause_graph_tracing(); | |
4698 | break; | |
4699 | } | |
4700 | return NOTIFY_DONE; | |
4701 | } | |
4702 | ||
287b6e68 FW |
4703 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
4704 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 4705 | { |
e7d3737e FW |
4706 | int ret = 0; |
4707 | ||
e6ea44e9 | 4708 | mutex_lock(&ftrace_lock); |
e7d3737e | 4709 | |
05ce5818 | 4710 | /* we currently allow only one tracer registered at a time */ |
597af815 | 4711 | if (ftrace_graph_active) { |
05ce5818 SR |
4712 | ret = -EBUSY; |
4713 | goto out; | |
4714 | } | |
4715 | ||
4a2b8dda FW |
4716 | ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call; |
4717 | register_pm_notifier(&ftrace_suspend_notifier); | |
4718 | ||
597af815 | 4719 | ftrace_graph_active++; |
fb52607a | 4720 | ret = start_graph_tracing(); |
f201ae23 | 4721 | if (ret) { |
597af815 | 4722 | ftrace_graph_active--; |
f201ae23 FW |
4723 | goto out; |
4724 | } | |
e53a6319 | 4725 | |
287b6e68 FW |
4726 | ftrace_graph_return = retfunc; |
4727 | ftrace_graph_entry = entryfunc; | |
e53a6319 | 4728 | |
a1cd6173 | 4729 | ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET); |
e7d3737e FW |
4730 | |
4731 | out: | |
e6ea44e9 | 4732 | mutex_unlock(&ftrace_lock); |
e7d3737e | 4733 | return ret; |
15e6cb36 FW |
4734 | } |
4735 | ||
fb52607a | 4736 | void unregister_ftrace_graph(void) |
15e6cb36 | 4737 | { |
e6ea44e9 | 4738 | mutex_lock(&ftrace_lock); |
e7d3737e | 4739 | |
597af815 | 4740 | if (unlikely(!ftrace_graph_active)) |
2aad1b76 SR |
4741 | goto out; |
4742 | ||
597af815 | 4743 | ftrace_graph_active--; |
287b6e68 | 4744 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; |
e49dc19c | 4745 | ftrace_graph_entry = ftrace_graph_entry_stub; |
bd69c30b | 4746 | ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET); |
4a2b8dda | 4747 | unregister_pm_notifier(&ftrace_suspend_notifier); |
38516ab5 | 4748 | unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
e7d3737e | 4749 | |
2aad1b76 | 4750 | out: |
e6ea44e9 | 4751 | mutex_unlock(&ftrace_lock); |
15e6cb36 | 4752 | } |
f201ae23 | 4753 | |
868baf07 SR |
4754 | static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack); |
4755 | ||
4756 | static void | |
4757 | graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack) | |
4758 | { | |
4759 | atomic_set(&t->tracing_graph_pause, 0); | |
4760 | atomic_set(&t->trace_overrun, 0); | |
4761 | t->ftrace_timestamp = 0; | |
25985edc | 4762 | /* make curr_ret_stack visible before we add the ret_stack */ |
868baf07 SR |
4763 | smp_wmb(); |
4764 | t->ret_stack = ret_stack; | |
4765 | } | |
4766 | ||
4767 | /* | |
4768 | * Allocate a return stack for the idle task. May be the first | |
4769 | * time through, or it may be done by CPU hotplug online. | |
4770 | */ | |
4771 | void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) | |
4772 | { | |
4773 | t->curr_ret_stack = -1; | |
4774 | /* | |
4775 | * The idle task has no parent, it either has its own | |
4776 | * stack or no stack at all. | |
4777 | */ | |
4778 | if (t->ret_stack) | |
4779 | WARN_ON(t->ret_stack != per_cpu(idle_ret_stack, cpu)); | |
4780 | ||
4781 | if (ftrace_graph_active) { | |
4782 | struct ftrace_ret_stack *ret_stack; | |
4783 | ||
4784 | ret_stack = per_cpu(idle_ret_stack, cpu); | |
4785 | if (!ret_stack) { | |
4786 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
4787 | * sizeof(struct ftrace_ret_stack), | |
4788 | GFP_KERNEL); | |
4789 | if (!ret_stack) | |
4790 | return; | |
4791 | per_cpu(idle_ret_stack, cpu) = ret_stack; | |
4792 | } | |
4793 | graph_init_task(t, ret_stack); | |
4794 | } | |
4795 | } | |
4796 | ||
f201ae23 | 4797 | /* Allocate a return stack for newly created task */ |
fb52607a | 4798 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 4799 | { |
84047e36 SR |
4800 | /* Make sure we do not use the parent ret_stack */ |
4801 | t->ret_stack = NULL; | |
ea14eb71 | 4802 | t->curr_ret_stack = -1; |
84047e36 | 4803 | |
597af815 | 4804 | if (ftrace_graph_active) { |
82310a32 SR |
4805 | struct ftrace_ret_stack *ret_stack; |
4806 | ||
4807 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
f201ae23 FW |
4808 | * sizeof(struct ftrace_ret_stack), |
4809 | GFP_KERNEL); | |
82310a32 | 4810 | if (!ret_stack) |
f201ae23 | 4811 | return; |
868baf07 | 4812 | graph_init_task(t, ret_stack); |
84047e36 | 4813 | } |
f201ae23 FW |
4814 | } |
4815 | ||
fb52607a | 4816 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 4817 | { |
eae849ca FW |
4818 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
4819 | ||
f201ae23 | 4820 | t->ret_stack = NULL; |
eae849ca FW |
4821 | /* NULL must become visible to IRQs before we free it: */ |
4822 | barrier(); | |
4823 | ||
4824 | kfree(ret_stack); | |
f201ae23 | 4825 | } |
14a866c5 SR |
4826 | |
4827 | void ftrace_graph_stop(void) | |
4828 | { | |
4829 | ftrace_stop(); | |
4830 | } | |
15e6cb36 | 4831 | #endif |