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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 | |
0a016409 SR |
114 | /* |
115 | * Traverse the ftrace_global_list, invoking all entries. The reason that we | |
116 | * can use rcu_dereference_raw() is that elements removed from this list | |
117 | * are simply leaked, so there is no need to interact with a grace-period | |
118 | * mechanism. The rcu_dereference_raw() calls are needed to handle | |
119 | * concurrent insertions into the ftrace_global_list. | |
120 | * | |
121 | * Silly Alpha and silly pointer-speculation compiler optimizations! | |
122 | */ | |
123 | #define do_for_each_ftrace_op(op, list) \ | |
124 | op = rcu_dereference_raw(list); \ | |
125 | do | |
126 | ||
127 | /* | |
128 | * Optimized for just a single item in the list (as that is the normal case). | |
129 | */ | |
130 | #define while_for_each_ftrace_op(op) \ | |
131 | while (likely(op = rcu_dereference_raw((op)->next)) && \ | |
132 | unlikely((op) != &ftrace_list_end)) | |
133 | ||
ea701f11 SR |
134 | /** |
135 | * ftrace_nr_registered_ops - return number of ops registered | |
136 | * | |
137 | * Returns the number of ftrace_ops registered and tracing functions | |
138 | */ | |
139 | int ftrace_nr_registered_ops(void) | |
140 | { | |
141 | struct ftrace_ops *ops; | |
142 | int cnt = 0; | |
143 | ||
144 | mutex_lock(&ftrace_lock); | |
145 | ||
146 | for (ops = ftrace_ops_list; | |
147 | ops != &ftrace_list_end; ops = ops->next) | |
148 | cnt++; | |
149 | ||
150 | mutex_unlock(&ftrace_lock); | |
151 | ||
152 | return cnt; | |
153 | } | |
154 | ||
2f5f6ad9 SR |
155 | static void |
156 | ftrace_global_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 157 | struct ftrace_ops *op, struct pt_regs *regs) |
16444a8a | 158 | { |
c29f122c SR |
159 | int bit; |
160 | ||
edc15caf SR |
161 | bit = trace_test_and_set_recursion(TRACE_GLOBAL_START, TRACE_GLOBAL_MAX); |
162 | if (bit < 0) | |
b1cff0ad | 163 | return; |
16444a8a | 164 | |
0a016409 | 165 | do_for_each_ftrace_op(op, ftrace_global_list) { |
a1e2e31d | 166 | op->func(ip, parent_ip, op, regs); |
0a016409 | 167 | } while_for_each_ftrace_op(op); |
edc15caf SR |
168 | |
169 | trace_clear_recursion(bit); | |
16444a8a ACM |
170 | } |
171 | ||
2f5f6ad9 | 172 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 173 | struct ftrace_ops *op, struct pt_regs *regs) |
df4fc315 | 174 | { |
0ef8cde5 | 175 | if (!test_tsk_trace_trace(current)) |
df4fc315 SR |
176 | return; |
177 | ||
a1e2e31d | 178 | ftrace_pid_function(ip, parent_ip, op, regs); |
df4fc315 SR |
179 | } |
180 | ||
181 | static void set_ftrace_pid_function(ftrace_func_t func) | |
182 | { | |
183 | /* do not set ftrace_pid_function to itself! */ | |
184 | if (func != ftrace_pid_func) | |
185 | ftrace_pid_function = func; | |
186 | } | |
187 | ||
16444a8a | 188 | /** |
3d083395 | 189 | * clear_ftrace_function - reset the ftrace function |
16444a8a | 190 | * |
3d083395 SR |
191 | * This NULLs the ftrace function and in essence stops |
192 | * tracing. There may be lag | |
16444a8a | 193 | */ |
3d083395 | 194 | void clear_ftrace_function(void) |
16444a8a | 195 | { |
3d083395 | 196 | ftrace_trace_function = ftrace_stub; |
df4fc315 | 197 | ftrace_pid_function = ftrace_stub; |
3d083395 SR |
198 | } |
199 | ||
e248491a JO |
200 | static void control_ops_disable_all(struct ftrace_ops *ops) |
201 | { | |
202 | int cpu; | |
203 | ||
204 | for_each_possible_cpu(cpu) | |
205 | *per_cpu_ptr(ops->disabled, cpu) = 1; | |
206 | } | |
207 | ||
208 | static int control_ops_alloc(struct ftrace_ops *ops) | |
209 | { | |
210 | int __percpu *disabled; | |
211 | ||
212 | disabled = alloc_percpu(int); | |
213 | if (!disabled) | |
214 | return -ENOMEM; | |
215 | ||
216 | ops->disabled = disabled; | |
217 | control_ops_disable_all(ops); | |
218 | return 0; | |
219 | } | |
220 | ||
221 | static void control_ops_free(struct ftrace_ops *ops) | |
222 | { | |
223 | free_percpu(ops->disabled); | |
224 | } | |
225 | ||
2b499381 | 226 | static void update_global_ops(void) |
491d0dcf SR |
227 | { |
228 | ftrace_func_t func; | |
229 | ||
230 | /* | |
231 | * If there's only one function registered, then call that | |
232 | * function directly. Otherwise, we need to iterate over the | |
233 | * registered callers. | |
234 | */ | |
b848914c | 235 | if (ftrace_global_list == &ftrace_list_end || |
63503794 | 236 | ftrace_global_list->next == &ftrace_list_end) { |
b848914c | 237 | func = ftrace_global_list->func; |
63503794 SR |
238 | /* |
239 | * As we are calling the function directly. | |
240 | * If it does not have recursion protection, | |
241 | * the function_trace_op needs to be updated | |
242 | * accordingly. | |
243 | */ | |
244 | if (ftrace_global_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) | |
245 | global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE; | |
246 | else | |
247 | global_ops.flags &= ~FTRACE_OPS_FL_RECURSION_SAFE; | |
248 | } else { | |
b848914c | 249 | func = ftrace_global_list_func; |
63503794 SR |
250 | /* The list has its own recursion protection. */ |
251 | global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE; | |
252 | } | |
253 | ||
491d0dcf SR |
254 | |
255 | /* If we filter on pids, update to use the pid function */ | |
256 | if (!list_empty(&ftrace_pids)) { | |
257 | set_ftrace_pid_function(func); | |
258 | func = ftrace_pid_func; | |
259 | } | |
2b499381 SR |
260 | |
261 | global_ops.func = func; | |
262 | } | |
263 | ||
264 | static void update_ftrace_function(void) | |
265 | { | |
266 | ftrace_func_t func; | |
267 | ||
268 | update_global_ops(); | |
269 | ||
cdbe61bf SR |
270 | /* |
271 | * If we are at the end of the list and this ops is | |
4740974a SR |
272 | * recursion safe and not dynamic and the arch supports passing ops, |
273 | * then have the mcount trampoline call the function directly. | |
cdbe61bf | 274 | */ |
b848914c | 275 | if (ftrace_ops_list == &ftrace_list_end || |
cdbe61bf | 276 | (ftrace_ops_list->next == &ftrace_list_end && |
2f5f6ad9 | 277 | !(ftrace_ops_list->flags & FTRACE_OPS_FL_DYNAMIC) && |
4740974a | 278 | (ftrace_ops_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) && |
ccf3672d | 279 | !FTRACE_FORCE_LIST_FUNC)) { |
2f5f6ad9 SR |
280 | /* Set the ftrace_ops that the arch callback uses */ |
281 | if (ftrace_ops_list == &global_ops) | |
282 | function_trace_op = ftrace_global_list; | |
283 | else | |
284 | function_trace_op = ftrace_ops_list; | |
b848914c | 285 | func = ftrace_ops_list->func; |
2f5f6ad9 SR |
286 | } else { |
287 | /* Just use the default ftrace_ops */ | |
288 | function_trace_op = &ftrace_list_end; | |
b848914c | 289 | func = ftrace_ops_list_func; |
2f5f6ad9 | 290 | } |
2b499381 | 291 | |
491d0dcf | 292 | ftrace_trace_function = func; |
491d0dcf SR |
293 | } |
294 | ||
2b499381 | 295 | static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
3d083395 | 296 | { |
2b499381 | 297 | ops->next = *list; |
16444a8a | 298 | /* |
b848914c | 299 | * We are entering ops into the list but another |
16444a8a ACM |
300 | * CPU might be walking that list. We need to make sure |
301 | * the ops->next pointer is valid before another CPU sees | |
b848914c | 302 | * the ops pointer included into the list. |
16444a8a | 303 | */ |
2b499381 | 304 | rcu_assign_pointer(*list, ops); |
16444a8a ACM |
305 | } |
306 | ||
2b499381 | 307 | static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
16444a8a | 308 | { |
16444a8a | 309 | struct ftrace_ops **p; |
16444a8a ACM |
310 | |
311 | /* | |
3d083395 SR |
312 | * If we are removing the last function, then simply point |
313 | * to the ftrace_stub. | |
16444a8a | 314 | */ |
2b499381 SR |
315 | if (*list == ops && ops->next == &ftrace_list_end) { |
316 | *list = &ftrace_list_end; | |
e6ea44e9 | 317 | return 0; |
16444a8a ACM |
318 | } |
319 | ||
2b499381 | 320 | for (p = list; *p != &ftrace_list_end; p = &(*p)->next) |
16444a8a ACM |
321 | if (*p == ops) |
322 | break; | |
323 | ||
e6ea44e9 SR |
324 | if (*p != ops) |
325 | return -1; | |
16444a8a ACM |
326 | |
327 | *p = (*p)->next; | |
2b499381 SR |
328 | return 0; |
329 | } | |
16444a8a | 330 | |
e248491a JO |
331 | static void add_ftrace_list_ops(struct ftrace_ops **list, |
332 | struct ftrace_ops *main_ops, | |
333 | struct ftrace_ops *ops) | |
334 | { | |
335 | int first = *list == &ftrace_list_end; | |
336 | add_ftrace_ops(list, ops); | |
337 | if (first) | |
338 | add_ftrace_ops(&ftrace_ops_list, main_ops); | |
339 | } | |
340 | ||
341 | static int remove_ftrace_list_ops(struct ftrace_ops **list, | |
342 | struct ftrace_ops *main_ops, | |
343 | struct ftrace_ops *ops) | |
344 | { | |
345 | int ret = remove_ftrace_ops(list, ops); | |
346 | if (!ret && *list == &ftrace_list_end) | |
347 | ret = remove_ftrace_ops(&ftrace_ops_list, main_ops); | |
348 | return ret; | |
349 | } | |
350 | ||
2b499381 SR |
351 | static int __register_ftrace_function(struct ftrace_ops *ops) |
352 | { | |
8d240dd8 | 353 | if (unlikely(ftrace_disabled)) |
2b499381 SR |
354 | return -ENODEV; |
355 | ||
356 | if (FTRACE_WARN_ON(ops == &global_ops)) | |
357 | return -EINVAL; | |
358 | ||
b848914c SR |
359 | if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED)) |
360 | return -EBUSY; | |
361 | ||
e248491a JO |
362 | /* We don't support both control and global flags set. */ |
363 | if ((ops->flags & FL_GLOBAL_CONTROL_MASK) == FL_GLOBAL_CONTROL_MASK) | |
364 | return -EINVAL; | |
365 | ||
06aeaaea | 366 | #ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
08f6fba5 SR |
367 | /* |
368 | * If the ftrace_ops specifies SAVE_REGS, then it only can be used | |
369 | * if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set. | |
370 | * Setting SAVE_REGS_IF_SUPPORTED makes SAVE_REGS irrelevant. | |
371 | */ | |
372 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS && | |
373 | !(ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)) | |
374 | return -EINVAL; | |
375 | ||
376 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED) | |
377 | ops->flags |= FTRACE_OPS_FL_SAVE_REGS; | |
378 | #endif | |
379 | ||
cdbe61bf SR |
380 | if (!core_kernel_data((unsigned long)ops)) |
381 | ops->flags |= FTRACE_OPS_FL_DYNAMIC; | |
382 | ||
b848914c | 383 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
e248491a | 384 | add_ftrace_list_ops(&ftrace_global_list, &global_ops, ops); |
b848914c | 385 | ops->flags |= FTRACE_OPS_FL_ENABLED; |
e248491a JO |
386 | } else if (ops->flags & FTRACE_OPS_FL_CONTROL) { |
387 | if (control_ops_alloc(ops)) | |
388 | return -ENOMEM; | |
389 | add_ftrace_list_ops(&ftrace_control_list, &control_ops, ops); | |
b848914c SR |
390 | } else |
391 | add_ftrace_ops(&ftrace_ops_list, ops); | |
392 | ||
2b499381 SR |
393 | if (ftrace_enabled) |
394 | update_ftrace_function(); | |
395 | ||
396 | return 0; | |
397 | } | |
398 | ||
399 | static int __unregister_ftrace_function(struct ftrace_ops *ops) | |
400 | { | |
401 | int ret; | |
402 | ||
403 | if (ftrace_disabled) | |
404 | return -ENODEV; | |
405 | ||
b848914c SR |
406 | if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) |
407 | return -EBUSY; | |
408 | ||
2b499381 SR |
409 | if (FTRACE_WARN_ON(ops == &global_ops)) |
410 | return -EINVAL; | |
411 | ||
b848914c | 412 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
e248491a JO |
413 | ret = remove_ftrace_list_ops(&ftrace_global_list, |
414 | &global_ops, ops); | |
b848914c SR |
415 | if (!ret) |
416 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; | |
e248491a JO |
417 | } else if (ops->flags & FTRACE_OPS_FL_CONTROL) { |
418 | ret = remove_ftrace_list_ops(&ftrace_control_list, | |
419 | &control_ops, ops); | |
420 | if (!ret) { | |
421 | /* | |
422 | * The ftrace_ops is now removed from the list, | |
423 | * so there'll be no new users. We must ensure | |
424 | * all current users are done before we free | |
425 | * the control data. | |
426 | */ | |
427 | synchronize_sched(); | |
428 | control_ops_free(ops); | |
429 | } | |
b848914c SR |
430 | } else |
431 | ret = remove_ftrace_ops(&ftrace_ops_list, ops); | |
432 | ||
2b499381 SR |
433 | if (ret < 0) |
434 | return ret; | |
b848914c | 435 | |
491d0dcf SR |
436 | if (ftrace_enabled) |
437 | update_ftrace_function(); | |
16444a8a | 438 | |
cdbe61bf SR |
439 | /* |
440 | * Dynamic ops may be freed, we must make sure that all | |
441 | * callers are done before leaving this function. | |
442 | */ | |
443 | if (ops->flags & FTRACE_OPS_FL_DYNAMIC) | |
444 | synchronize_sched(); | |
445 | ||
e6ea44e9 | 446 | return 0; |
3d083395 SR |
447 | } |
448 | ||
df4fc315 SR |
449 | static void ftrace_update_pid_func(void) |
450 | { | |
491d0dcf | 451 | /* Only do something if we are tracing something */ |
df4fc315 | 452 | if (ftrace_trace_function == ftrace_stub) |
10dd3ebe | 453 | return; |
df4fc315 | 454 | |
491d0dcf | 455 | update_ftrace_function(); |
df4fc315 SR |
456 | } |
457 | ||
493762fc SR |
458 | #ifdef CONFIG_FUNCTION_PROFILER |
459 | struct ftrace_profile { | |
460 | struct hlist_node node; | |
461 | unsigned long ip; | |
462 | unsigned long counter; | |
0706f1c4 SR |
463 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
464 | unsigned long long time; | |
e330b3bc | 465 | unsigned long long time_squared; |
0706f1c4 | 466 | #endif |
8fc0c701 SR |
467 | }; |
468 | ||
493762fc SR |
469 | struct ftrace_profile_page { |
470 | struct ftrace_profile_page *next; | |
471 | unsigned long index; | |
472 | struct ftrace_profile records[]; | |
d61f82d0 SR |
473 | }; |
474 | ||
cafb168a SR |
475 | struct ftrace_profile_stat { |
476 | atomic_t disabled; | |
477 | struct hlist_head *hash; | |
478 | struct ftrace_profile_page *pages; | |
479 | struct ftrace_profile_page *start; | |
480 | struct tracer_stat stat; | |
481 | }; | |
482 | ||
493762fc SR |
483 | #define PROFILE_RECORDS_SIZE \ |
484 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | |
5072c59f | 485 | |
493762fc SR |
486 | #define PROFILES_PER_PAGE \ |
487 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | |
3d083395 | 488 | |
fb9fb015 SR |
489 | static int ftrace_profile_bits __read_mostly; |
490 | static int ftrace_profile_enabled __read_mostly; | |
491 | ||
492 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ | |
bac429f0 SR |
493 | static DEFINE_MUTEX(ftrace_profile_lock); |
494 | ||
cafb168a | 495 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); |
493762fc SR |
496 | |
497 | #define FTRACE_PROFILE_HASH_SIZE 1024 /* must be power of 2 */ | |
498 | ||
bac429f0 SR |
499 | static void * |
500 | function_stat_next(void *v, int idx) | |
501 | { | |
493762fc SR |
502 | struct ftrace_profile *rec = v; |
503 | struct ftrace_profile_page *pg; | |
bac429f0 | 504 | |
493762fc | 505 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
bac429f0 SR |
506 | |
507 | again: | |
0296e425 LZ |
508 | if (idx != 0) |
509 | rec++; | |
510 | ||
bac429f0 SR |
511 | if ((void *)rec >= (void *)&pg->records[pg->index]) { |
512 | pg = pg->next; | |
513 | if (!pg) | |
514 | return NULL; | |
515 | rec = &pg->records[0]; | |
493762fc SR |
516 | if (!rec->counter) |
517 | goto again; | |
bac429f0 SR |
518 | } |
519 | ||
bac429f0 SR |
520 | return rec; |
521 | } | |
522 | ||
523 | static void *function_stat_start(struct tracer_stat *trace) | |
524 | { | |
cafb168a SR |
525 | struct ftrace_profile_stat *stat = |
526 | container_of(trace, struct ftrace_profile_stat, stat); | |
527 | ||
528 | if (!stat || !stat->start) | |
529 | return NULL; | |
530 | ||
531 | return function_stat_next(&stat->start->records[0], 0); | |
bac429f0 SR |
532 | } |
533 | ||
0706f1c4 SR |
534 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
535 | /* function graph compares on total time */ | |
536 | static int function_stat_cmp(void *p1, void *p2) | |
537 | { | |
538 | struct ftrace_profile *a = p1; | |
539 | struct ftrace_profile *b = p2; | |
540 | ||
541 | if (a->time < b->time) | |
542 | return -1; | |
543 | if (a->time > b->time) | |
544 | return 1; | |
545 | else | |
546 | return 0; | |
547 | } | |
548 | #else | |
549 | /* not function graph compares against hits */ | |
bac429f0 SR |
550 | static int function_stat_cmp(void *p1, void *p2) |
551 | { | |
493762fc SR |
552 | struct ftrace_profile *a = p1; |
553 | struct ftrace_profile *b = p2; | |
bac429f0 SR |
554 | |
555 | if (a->counter < b->counter) | |
556 | return -1; | |
557 | if (a->counter > b->counter) | |
558 | return 1; | |
559 | else | |
560 | return 0; | |
561 | } | |
0706f1c4 | 562 | #endif |
bac429f0 SR |
563 | |
564 | static int function_stat_headers(struct seq_file *m) | |
565 | { | |
0706f1c4 | 566 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b | 567 | seq_printf(m, " Function " |
e330b3bc | 568 | "Hit Time Avg s^2\n" |
34886c8b | 569 | " -------- " |
e330b3bc | 570 | "--- ---- --- ---\n"); |
0706f1c4 | 571 | #else |
bac429f0 SR |
572 | seq_printf(m, " Function Hit\n" |
573 | " -------- ---\n"); | |
0706f1c4 | 574 | #endif |
bac429f0 SR |
575 | return 0; |
576 | } | |
577 | ||
578 | static int function_stat_show(struct seq_file *m, void *v) | |
579 | { | |
493762fc | 580 | struct ftrace_profile *rec = v; |
bac429f0 | 581 | char str[KSYM_SYMBOL_LEN]; |
3aaba20f | 582 | int ret = 0; |
0706f1c4 | 583 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b SR |
584 | static struct trace_seq s; |
585 | unsigned long long avg; | |
e330b3bc | 586 | unsigned long long stddev; |
0706f1c4 | 587 | #endif |
3aaba20f LZ |
588 | mutex_lock(&ftrace_profile_lock); |
589 | ||
590 | /* we raced with function_profile_reset() */ | |
591 | if (unlikely(rec->counter == 0)) { | |
592 | ret = -EBUSY; | |
593 | goto out; | |
594 | } | |
bac429f0 SR |
595 | |
596 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
0706f1c4 SR |
597 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); |
598 | ||
599 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
600 | seq_printf(m, " "); | |
34886c8b SR |
601 | avg = rec->time; |
602 | do_div(avg, rec->counter); | |
603 | ||
e330b3bc CD |
604 | /* Sample standard deviation (s^2) */ |
605 | if (rec->counter <= 1) | |
606 | stddev = 0; | |
607 | else { | |
608 | stddev = rec->time_squared - rec->counter * avg * avg; | |
609 | /* | |
610 | * Divide only 1000 for ns^2 -> us^2 conversion. | |
611 | * trace_print_graph_duration will divide 1000 again. | |
612 | */ | |
613 | do_div(stddev, (rec->counter - 1) * 1000); | |
614 | } | |
615 | ||
34886c8b SR |
616 | trace_seq_init(&s); |
617 | trace_print_graph_duration(rec->time, &s); | |
618 | trace_seq_puts(&s, " "); | |
619 | trace_print_graph_duration(avg, &s); | |
e330b3bc CD |
620 | trace_seq_puts(&s, " "); |
621 | trace_print_graph_duration(stddev, &s); | |
0706f1c4 | 622 | trace_print_seq(m, &s); |
0706f1c4 SR |
623 | #endif |
624 | seq_putc(m, '\n'); | |
3aaba20f LZ |
625 | out: |
626 | mutex_unlock(&ftrace_profile_lock); | |
bac429f0 | 627 | |
3aaba20f | 628 | return ret; |
bac429f0 SR |
629 | } |
630 | ||
cafb168a | 631 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) |
bac429f0 | 632 | { |
493762fc | 633 | struct ftrace_profile_page *pg; |
bac429f0 | 634 | |
cafb168a | 635 | pg = stat->pages = stat->start; |
bac429f0 | 636 | |
493762fc SR |
637 | while (pg) { |
638 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | |
639 | pg->index = 0; | |
640 | pg = pg->next; | |
bac429f0 SR |
641 | } |
642 | ||
cafb168a | 643 | memset(stat->hash, 0, |
493762fc SR |
644 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); |
645 | } | |
bac429f0 | 646 | |
cafb168a | 647 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) |
493762fc SR |
648 | { |
649 | struct ftrace_profile_page *pg; | |
318e0a73 SR |
650 | int functions; |
651 | int pages; | |
493762fc | 652 | int i; |
bac429f0 | 653 | |
493762fc | 654 | /* If we already allocated, do nothing */ |
cafb168a | 655 | if (stat->pages) |
493762fc | 656 | return 0; |
bac429f0 | 657 | |
cafb168a SR |
658 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); |
659 | if (!stat->pages) | |
493762fc | 660 | return -ENOMEM; |
bac429f0 | 661 | |
318e0a73 SR |
662 | #ifdef CONFIG_DYNAMIC_FTRACE |
663 | functions = ftrace_update_tot_cnt; | |
664 | #else | |
665 | /* | |
666 | * We do not know the number of functions that exist because | |
667 | * dynamic tracing is what counts them. With past experience | |
668 | * we have around 20K functions. That should be more than enough. | |
669 | * It is highly unlikely we will execute every function in | |
670 | * the kernel. | |
671 | */ | |
672 | functions = 20000; | |
673 | #endif | |
674 | ||
cafb168a | 675 | pg = stat->start = stat->pages; |
bac429f0 | 676 | |
318e0a73 SR |
677 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); |
678 | ||
679 | for (i = 0; i < pages; i++) { | |
493762fc | 680 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
493762fc | 681 | if (!pg->next) |
318e0a73 | 682 | goto out_free; |
493762fc SR |
683 | pg = pg->next; |
684 | } | |
685 | ||
686 | return 0; | |
318e0a73 SR |
687 | |
688 | out_free: | |
689 | pg = stat->start; | |
690 | while (pg) { | |
691 | unsigned long tmp = (unsigned long)pg; | |
692 | ||
693 | pg = pg->next; | |
694 | free_page(tmp); | |
695 | } | |
696 | ||
697 | free_page((unsigned long)stat->pages); | |
698 | stat->pages = NULL; | |
699 | stat->start = NULL; | |
700 | ||
701 | return -ENOMEM; | |
bac429f0 SR |
702 | } |
703 | ||
cafb168a | 704 | static int ftrace_profile_init_cpu(int cpu) |
bac429f0 | 705 | { |
cafb168a | 706 | struct ftrace_profile_stat *stat; |
493762fc | 707 | int size; |
bac429f0 | 708 | |
cafb168a SR |
709 | stat = &per_cpu(ftrace_profile_stats, cpu); |
710 | ||
711 | if (stat->hash) { | |
493762fc | 712 | /* If the profile is already created, simply reset it */ |
cafb168a | 713 | ftrace_profile_reset(stat); |
493762fc SR |
714 | return 0; |
715 | } | |
bac429f0 | 716 | |
493762fc SR |
717 | /* |
718 | * We are profiling all functions, but usually only a few thousand | |
719 | * functions are hit. We'll make a hash of 1024 items. | |
720 | */ | |
721 | size = FTRACE_PROFILE_HASH_SIZE; | |
bac429f0 | 722 | |
cafb168a | 723 | stat->hash = kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL); |
493762fc | 724 | |
cafb168a | 725 | if (!stat->hash) |
493762fc SR |
726 | return -ENOMEM; |
727 | ||
cafb168a SR |
728 | if (!ftrace_profile_bits) { |
729 | size--; | |
493762fc | 730 | |
cafb168a SR |
731 | for (; size; size >>= 1) |
732 | ftrace_profile_bits++; | |
733 | } | |
493762fc | 734 | |
318e0a73 | 735 | /* Preallocate the function profiling pages */ |
cafb168a SR |
736 | if (ftrace_profile_pages_init(stat) < 0) { |
737 | kfree(stat->hash); | |
738 | stat->hash = NULL; | |
493762fc SR |
739 | return -ENOMEM; |
740 | } | |
741 | ||
742 | return 0; | |
bac429f0 SR |
743 | } |
744 | ||
cafb168a SR |
745 | static int ftrace_profile_init(void) |
746 | { | |
747 | int cpu; | |
748 | int ret = 0; | |
749 | ||
750 | for_each_online_cpu(cpu) { | |
751 | ret = ftrace_profile_init_cpu(cpu); | |
752 | if (ret) | |
753 | break; | |
754 | } | |
755 | ||
756 | return ret; | |
757 | } | |
758 | ||
493762fc | 759 | /* interrupts must be disabled */ |
cafb168a SR |
760 | static struct ftrace_profile * |
761 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) | |
bac429f0 | 762 | { |
493762fc | 763 | struct ftrace_profile *rec; |
bac429f0 | 764 | struct hlist_head *hhd; |
bac429f0 SR |
765 | unsigned long key; |
766 | ||
bac429f0 | 767 | key = hash_long(ip, ftrace_profile_bits); |
cafb168a | 768 | hhd = &stat->hash[key]; |
bac429f0 SR |
769 | |
770 | if (hlist_empty(hhd)) | |
771 | return NULL; | |
772 | ||
b67bfe0d | 773 | hlist_for_each_entry_rcu(rec, hhd, node) { |
bac429f0 | 774 | if (rec->ip == ip) |
493762fc SR |
775 | return rec; |
776 | } | |
777 | ||
778 | return NULL; | |
779 | } | |
780 | ||
cafb168a SR |
781 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, |
782 | struct ftrace_profile *rec) | |
493762fc SR |
783 | { |
784 | unsigned long key; | |
785 | ||
786 | key = hash_long(rec->ip, ftrace_profile_bits); | |
cafb168a | 787 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); |
493762fc SR |
788 | } |
789 | ||
318e0a73 SR |
790 | /* |
791 | * The memory is already allocated, this simply finds a new record to use. | |
792 | */ | |
493762fc | 793 | static struct ftrace_profile * |
318e0a73 | 794 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) |
493762fc SR |
795 | { |
796 | struct ftrace_profile *rec = NULL; | |
797 | ||
318e0a73 | 798 | /* prevent recursion (from NMIs) */ |
cafb168a | 799 | if (atomic_inc_return(&stat->disabled) != 1) |
493762fc SR |
800 | goto out; |
801 | ||
493762fc | 802 | /* |
318e0a73 SR |
803 | * Try to find the function again since an NMI |
804 | * could have added it | |
493762fc | 805 | */ |
cafb168a | 806 | rec = ftrace_find_profiled_func(stat, ip); |
493762fc | 807 | if (rec) |
cafb168a | 808 | goto out; |
493762fc | 809 | |
cafb168a SR |
810 | if (stat->pages->index == PROFILES_PER_PAGE) { |
811 | if (!stat->pages->next) | |
812 | goto out; | |
813 | stat->pages = stat->pages->next; | |
bac429f0 | 814 | } |
493762fc | 815 | |
cafb168a | 816 | rec = &stat->pages->records[stat->pages->index++]; |
493762fc | 817 | rec->ip = ip; |
cafb168a | 818 | ftrace_add_profile(stat, rec); |
493762fc | 819 | |
bac429f0 | 820 | out: |
cafb168a | 821 | atomic_dec(&stat->disabled); |
bac429f0 SR |
822 | |
823 | return rec; | |
824 | } | |
825 | ||
826 | static void | |
2f5f6ad9 | 827 | function_profile_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 828 | struct ftrace_ops *ops, struct pt_regs *regs) |
bac429f0 | 829 | { |
cafb168a | 830 | struct ftrace_profile_stat *stat; |
493762fc | 831 | struct ftrace_profile *rec; |
bac429f0 SR |
832 | unsigned long flags; |
833 | ||
834 | if (!ftrace_profile_enabled) | |
835 | return; | |
836 | ||
837 | local_irq_save(flags); | |
cafb168a SR |
838 | |
839 | stat = &__get_cpu_var(ftrace_profile_stats); | |
0f6ce3de | 840 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
841 | goto out; |
842 | ||
843 | rec = ftrace_find_profiled_func(stat, ip); | |
493762fc | 844 | if (!rec) { |
318e0a73 | 845 | rec = ftrace_profile_alloc(stat, ip); |
493762fc SR |
846 | if (!rec) |
847 | goto out; | |
848 | } | |
bac429f0 SR |
849 | |
850 | rec->counter++; | |
851 | out: | |
852 | local_irq_restore(flags); | |
853 | } | |
854 | ||
0706f1c4 SR |
855 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
856 | static int profile_graph_entry(struct ftrace_graph_ent *trace) | |
857 | { | |
a1e2e31d | 858 | function_profile_call(trace->func, 0, NULL, NULL); |
0706f1c4 SR |
859 | return 1; |
860 | } | |
861 | ||
862 | static void profile_graph_return(struct ftrace_graph_ret *trace) | |
863 | { | |
cafb168a | 864 | struct ftrace_profile_stat *stat; |
a2a16d6a | 865 | unsigned long long calltime; |
0706f1c4 | 866 | struct ftrace_profile *rec; |
cafb168a | 867 | unsigned long flags; |
0706f1c4 SR |
868 | |
869 | local_irq_save(flags); | |
cafb168a | 870 | stat = &__get_cpu_var(ftrace_profile_stats); |
0f6ce3de | 871 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
872 | goto out; |
873 | ||
37e44bc5 SR |
874 | /* If the calltime was zero'd ignore it */ |
875 | if (!trace->calltime) | |
876 | goto out; | |
877 | ||
a2a16d6a SR |
878 | calltime = trace->rettime - trace->calltime; |
879 | ||
880 | if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) { | |
881 | int index; | |
882 | ||
883 | index = trace->depth; | |
884 | ||
885 | /* Append this call time to the parent time to subtract */ | |
886 | if (index) | |
887 | current->ret_stack[index - 1].subtime += calltime; | |
888 | ||
889 | if (current->ret_stack[index].subtime < calltime) | |
890 | calltime -= current->ret_stack[index].subtime; | |
891 | else | |
892 | calltime = 0; | |
893 | } | |
894 | ||
cafb168a | 895 | rec = ftrace_find_profiled_func(stat, trace->func); |
e330b3bc | 896 | if (rec) { |
a2a16d6a | 897 | rec->time += calltime; |
e330b3bc CD |
898 | rec->time_squared += calltime * calltime; |
899 | } | |
a2a16d6a | 900 | |
cafb168a | 901 | out: |
0706f1c4 SR |
902 | local_irq_restore(flags); |
903 | } | |
904 | ||
905 | static int register_ftrace_profiler(void) | |
906 | { | |
907 | return register_ftrace_graph(&profile_graph_return, | |
908 | &profile_graph_entry); | |
909 | } | |
910 | ||
911 | static void unregister_ftrace_profiler(void) | |
912 | { | |
913 | unregister_ftrace_graph(); | |
914 | } | |
915 | #else | |
bd38c0e6 | 916 | static struct ftrace_ops ftrace_profile_ops __read_mostly = { |
fb9fb015 | 917 | .func = function_profile_call, |
4740974a | 918 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
bac429f0 SR |
919 | }; |
920 | ||
0706f1c4 SR |
921 | static int register_ftrace_profiler(void) |
922 | { | |
923 | return register_ftrace_function(&ftrace_profile_ops); | |
924 | } | |
925 | ||
926 | static void unregister_ftrace_profiler(void) | |
927 | { | |
928 | unregister_ftrace_function(&ftrace_profile_ops); | |
929 | } | |
930 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
931 | ||
bac429f0 SR |
932 | static ssize_t |
933 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | |
934 | size_t cnt, loff_t *ppos) | |
935 | { | |
936 | unsigned long val; | |
bac429f0 SR |
937 | int ret; |
938 | ||
22fe9b54 PH |
939 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
940 | if (ret) | |
bac429f0 SR |
941 | return ret; |
942 | ||
943 | val = !!val; | |
944 | ||
945 | mutex_lock(&ftrace_profile_lock); | |
946 | if (ftrace_profile_enabled ^ val) { | |
947 | if (val) { | |
493762fc SR |
948 | ret = ftrace_profile_init(); |
949 | if (ret < 0) { | |
950 | cnt = ret; | |
951 | goto out; | |
952 | } | |
953 | ||
0706f1c4 SR |
954 | ret = register_ftrace_profiler(); |
955 | if (ret < 0) { | |
956 | cnt = ret; | |
957 | goto out; | |
958 | } | |
bac429f0 SR |
959 | ftrace_profile_enabled = 1; |
960 | } else { | |
961 | ftrace_profile_enabled = 0; | |
0f6ce3de SR |
962 | /* |
963 | * unregister_ftrace_profiler calls stop_machine | |
964 | * so this acts like an synchronize_sched. | |
965 | */ | |
0706f1c4 | 966 | unregister_ftrace_profiler(); |
bac429f0 SR |
967 | } |
968 | } | |
493762fc | 969 | out: |
bac429f0 SR |
970 | mutex_unlock(&ftrace_profile_lock); |
971 | ||
cf8517cf | 972 | *ppos += cnt; |
bac429f0 SR |
973 | |
974 | return cnt; | |
975 | } | |
976 | ||
493762fc SR |
977 | static ssize_t |
978 | ftrace_profile_read(struct file *filp, char __user *ubuf, | |
979 | size_t cnt, loff_t *ppos) | |
980 | { | |
fb9fb015 | 981 | char buf[64]; /* big enough to hold a number */ |
493762fc SR |
982 | int r; |
983 | ||
984 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | |
985 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
986 | } | |
987 | ||
bac429f0 SR |
988 | static const struct file_operations ftrace_profile_fops = { |
989 | .open = tracing_open_generic, | |
990 | .read = ftrace_profile_read, | |
991 | .write = ftrace_profile_write, | |
6038f373 | 992 | .llseek = default_llseek, |
bac429f0 SR |
993 | }; |
994 | ||
cafb168a SR |
995 | /* used to initialize the real stat files */ |
996 | static struct tracer_stat function_stats __initdata = { | |
fb9fb015 SR |
997 | .name = "functions", |
998 | .stat_start = function_stat_start, | |
999 | .stat_next = function_stat_next, | |
1000 | .stat_cmp = function_stat_cmp, | |
1001 | .stat_headers = function_stat_headers, | |
1002 | .stat_show = function_stat_show | |
cafb168a SR |
1003 | }; |
1004 | ||
6ab5d668 | 1005 | static __init void ftrace_profile_debugfs(struct dentry *d_tracer) |
bac429f0 | 1006 | { |
cafb168a | 1007 | struct ftrace_profile_stat *stat; |
bac429f0 | 1008 | struct dentry *entry; |
cafb168a | 1009 | char *name; |
bac429f0 | 1010 | int ret; |
cafb168a SR |
1011 | int cpu; |
1012 | ||
1013 | for_each_possible_cpu(cpu) { | |
1014 | stat = &per_cpu(ftrace_profile_stats, cpu); | |
1015 | ||
1016 | /* allocate enough for function name + cpu number */ | |
1017 | name = kmalloc(32, GFP_KERNEL); | |
1018 | if (!name) { | |
1019 | /* | |
1020 | * The files created are permanent, if something happens | |
1021 | * we still do not free memory. | |
1022 | */ | |
cafb168a SR |
1023 | WARN(1, |
1024 | "Could not allocate stat file for cpu %d\n", | |
1025 | cpu); | |
1026 | return; | |
1027 | } | |
1028 | stat->stat = function_stats; | |
1029 | snprintf(name, 32, "function%d", cpu); | |
1030 | stat->stat.name = name; | |
1031 | ret = register_stat_tracer(&stat->stat); | |
1032 | if (ret) { | |
1033 | WARN(1, | |
1034 | "Could not register function stat for cpu %d\n", | |
1035 | cpu); | |
1036 | kfree(name); | |
1037 | return; | |
1038 | } | |
bac429f0 SR |
1039 | } |
1040 | ||
1041 | entry = debugfs_create_file("function_profile_enabled", 0644, | |
1042 | d_tracer, NULL, &ftrace_profile_fops); | |
1043 | if (!entry) | |
1044 | pr_warning("Could not create debugfs " | |
1045 | "'function_profile_enabled' entry\n"); | |
1046 | } | |
1047 | ||
bac429f0 | 1048 | #else /* CONFIG_FUNCTION_PROFILER */ |
6ab5d668 | 1049 | static __init void ftrace_profile_debugfs(struct dentry *d_tracer) |
bac429f0 SR |
1050 | { |
1051 | } | |
bac429f0 SR |
1052 | #endif /* CONFIG_FUNCTION_PROFILER */ |
1053 | ||
493762fc SR |
1054 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; |
1055 | ||
1056 | #ifdef CONFIG_DYNAMIC_FTRACE | |
1057 | ||
1058 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD | |
1059 | # error Dynamic ftrace depends on MCOUNT_RECORD | |
1060 | #endif | |
1061 | ||
1062 | static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly; | |
1063 | ||
1064 | struct ftrace_func_probe { | |
1065 | struct hlist_node node; | |
1066 | struct ftrace_probe_ops *ops; | |
1067 | unsigned long flags; | |
1068 | unsigned long ip; | |
1069 | void *data; | |
1070 | struct rcu_head rcu; | |
1071 | }; | |
1072 | ||
b448c4e3 SR |
1073 | struct ftrace_func_entry { |
1074 | struct hlist_node hlist; | |
1075 | unsigned long ip; | |
1076 | }; | |
1077 | ||
1078 | struct ftrace_hash { | |
1079 | unsigned long size_bits; | |
1080 | struct hlist_head *buckets; | |
1081 | unsigned long count; | |
07fd5515 | 1082 | struct rcu_head rcu; |
b448c4e3 SR |
1083 | }; |
1084 | ||
33dc9b12 SR |
1085 | /* |
1086 | * We make these constant because no one should touch them, | |
1087 | * but they are used as the default "empty hash", to avoid allocating | |
1088 | * it all the time. These are in a read only section such that if | |
1089 | * anyone does try to modify it, it will cause an exception. | |
1090 | */ | |
1091 | static const struct hlist_head empty_buckets[1]; | |
1092 | static const struct ftrace_hash empty_hash = { | |
1093 | .buckets = (struct hlist_head *)empty_buckets, | |
1cf41dd7 | 1094 | }; |
33dc9b12 | 1095 | #define EMPTY_HASH ((struct ftrace_hash *)&empty_hash) |
493762fc | 1096 | |
2b499381 | 1097 | static struct ftrace_ops global_ops = { |
f45948e8 | 1098 | .func = ftrace_stub, |
33dc9b12 SR |
1099 | .notrace_hash = EMPTY_HASH, |
1100 | .filter_hash = EMPTY_HASH, | |
4740974a | 1101 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
f45948e8 SR |
1102 | }; |
1103 | ||
493762fc SR |
1104 | static DEFINE_MUTEX(ftrace_regex_lock); |
1105 | ||
1106 | struct ftrace_page { | |
1107 | struct ftrace_page *next; | |
a7900875 | 1108 | struct dyn_ftrace *records; |
493762fc | 1109 | int index; |
a7900875 | 1110 | int size; |
493762fc SR |
1111 | }; |
1112 | ||
85ae32ae SR |
1113 | static struct ftrace_page *ftrace_new_pgs; |
1114 | ||
a7900875 SR |
1115 | #define ENTRY_SIZE sizeof(struct dyn_ftrace) |
1116 | #define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE) | |
493762fc SR |
1117 | |
1118 | /* estimate from running different kernels */ | |
1119 | #define NR_TO_INIT 10000 | |
1120 | ||
1121 | static struct ftrace_page *ftrace_pages_start; | |
1122 | static struct ftrace_page *ftrace_pages; | |
1123 | ||
06a51d93 SR |
1124 | static bool ftrace_hash_empty(struct ftrace_hash *hash) |
1125 | { | |
1126 | return !hash || !hash->count; | |
1127 | } | |
1128 | ||
b448c4e3 SR |
1129 | static struct ftrace_func_entry * |
1130 | ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
1131 | { | |
1132 | unsigned long key; | |
1133 | struct ftrace_func_entry *entry; | |
1134 | struct hlist_head *hhd; | |
b448c4e3 | 1135 | |
06a51d93 | 1136 | if (ftrace_hash_empty(hash)) |
b448c4e3 SR |
1137 | return NULL; |
1138 | ||
1139 | if (hash->size_bits > 0) | |
1140 | key = hash_long(ip, hash->size_bits); | |
1141 | else | |
1142 | key = 0; | |
1143 | ||
1144 | hhd = &hash->buckets[key]; | |
1145 | ||
b67bfe0d | 1146 | hlist_for_each_entry_rcu(entry, hhd, hlist) { |
b448c4e3 SR |
1147 | if (entry->ip == ip) |
1148 | return entry; | |
1149 | } | |
1150 | return NULL; | |
1151 | } | |
1152 | ||
33dc9b12 SR |
1153 | static void __add_hash_entry(struct ftrace_hash *hash, |
1154 | struct ftrace_func_entry *entry) | |
b448c4e3 | 1155 | { |
b448c4e3 SR |
1156 | struct hlist_head *hhd; |
1157 | unsigned long key; | |
1158 | ||
b448c4e3 | 1159 | if (hash->size_bits) |
33dc9b12 | 1160 | key = hash_long(entry->ip, hash->size_bits); |
b448c4e3 SR |
1161 | else |
1162 | key = 0; | |
1163 | ||
b448c4e3 SR |
1164 | hhd = &hash->buckets[key]; |
1165 | hlist_add_head(&entry->hlist, hhd); | |
1166 | hash->count++; | |
33dc9b12 SR |
1167 | } |
1168 | ||
1169 | static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) | |
1170 | { | |
1171 | struct ftrace_func_entry *entry; | |
1172 | ||
1173 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
1174 | if (!entry) | |
1175 | return -ENOMEM; | |
1176 | ||
1177 | entry->ip = ip; | |
1178 | __add_hash_entry(hash, entry); | |
b448c4e3 SR |
1179 | |
1180 | return 0; | |
1181 | } | |
1182 | ||
1183 | static void | |
33dc9b12 | 1184 | free_hash_entry(struct ftrace_hash *hash, |
b448c4e3 SR |
1185 | struct ftrace_func_entry *entry) |
1186 | { | |
1187 | hlist_del(&entry->hlist); | |
1188 | kfree(entry); | |
1189 | hash->count--; | |
1190 | } | |
1191 | ||
33dc9b12 SR |
1192 | static void |
1193 | remove_hash_entry(struct ftrace_hash *hash, | |
1194 | struct ftrace_func_entry *entry) | |
1195 | { | |
1196 | hlist_del(&entry->hlist); | |
1197 | hash->count--; | |
1198 | } | |
1199 | ||
b448c4e3 SR |
1200 | static void ftrace_hash_clear(struct ftrace_hash *hash) |
1201 | { | |
1202 | struct hlist_head *hhd; | |
b67bfe0d | 1203 | struct hlist_node *tn; |
b448c4e3 SR |
1204 | struct ftrace_func_entry *entry; |
1205 | int size = 1 << hash->size_bits; | |
1206 | int i; | |
1207 | ||
33dc9b12 SR |
1208 | if (!hash->count) |
1209 | return; | |
1210 | ||
b448c4e3 SR |
1211 | for (i = 0; i < size; i++) { |
1212 | hhd = &hash->buckets[i]; | |
b67bfe0d | 1213 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) |
33dc9b12 | 1214 | free_hash_entry(hash, entry); |
b448c4e3 SR |
1215 | } |
1216 | FTRACE_WARN_ON(hash->count); | |
1217 | } | |
1218 | ||
33dc9b12 SR |
1219 | static void free_ftrace_hash(struct ftrace_hash *hash) |
1220 | { | |
1221 | if (!hash || hash == EMPTY_HASH) | |
1222 | return; | |
1223 | ftrace_hash_clear(hash); | |
1224 | kfree(hash->buckets); | |
1225 | kfree(hash); | |
1226 | } | |
1227 | ||
07fd5515 SR |
1228 | static void __free_ftrace_hash_rcu(struct rcu_head *rcu) |
1229 | { | |
1230 | struct ftrace_hash *hash; | |
1231 | ||
1232 | hash = container_of(rcu, struct ftrace_hash, rcu); | |
1233 | free_ftrace_hash(hash); | |
1234 | } | |
1235 | ||
1236 | static void free_ftrace_hash_rcu(struct ftrace_hash *hash) | |
1237 | { | |
1238 | if (!hash || hash == EMPTY_HASH) | |
1239 | return; | |
1240 | call_rcu_sched(&hash->rcu, __free_ftrace_hash_rcu); | |
1241 | } | |
1242 | ||
5500fa51 JO |
1243 | void ftrace_free_filter(struct ftrace_ops *ops) |
1244 | { | |
1245 | free_ftrace_hash(ops->filter_hash); | |
1246 | free_ftrace_hash(ops->notrace_hash); | |
1247 | } | |
1248 | ||
33dc9b12 SR |
1249 | static struct ftrace_hash *alloc_ftrace_hash(int size_bits) |
1250 | { | |
1251 | struct ftrace_hash *hash; | |
1252 | int size; | |
1253 | ||
1254 | hash = kzalloc(sizeof(*hash), GFP_KERNEL); | |
1255 | if (!hash) | |
1256 | return NULL; | |
1257 | ||
1258 | size = 1 << size_bits; | |
47b0edcb | 1259 | hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL); |
33dc9b12 SR |
1260 | |
1261 | if (!hash->buckets) { | |
1262 | kfree(hash); | |
1263 | return NULL; | |
1264 | } | |
1265 | ||
1266 | hash->size_bits = size_bits; | |
1267 | ||
1268 | return hash; | |
1269 | } | |
1270 | ||
1271 | static struct ftrace_hash * | |
1272 | alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) | |
1273 | { | |
1274 | struct ftrace_func_entry *entry; | |
1275 | struct ftrace_hash *new_hash; | |
33dc9b12 SR |
1276 | int size; |
1277 | int ret; | |
1278 | int i; | |
1279 | ||
1280 | new_hash = alloc_ftrace_hash(size_bits); | |
1281 | if (!new_hash) | |
1282 | return NULL; | |
1283 | ||
1284 | /* Empty hash? */ | |
06a51d93 | 1285 | if (ftrace_hash_empty(hash)) |
33dc9b12 SR |
1286 | return new_hash; |
1287 | ||
1288 | size = 1 << hash->size_bits; | |
1289 | for (i = 0; i < size; i++) { | |
b67bfe0d | 1290 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { |
33dc9b12 SR |
1291 | ret = add_hash_entry(new_hash, entry->ip); |
1292 | if (ret < 0) | |
1293 | goto free_hash; | |
1294 | } | |
1295 | } | |
1296 | ||
1297 | FTRACE_WARN_ON(new_hash->count != hash->count); | |
1298 | ||
1299 | return new_hash; | |
1300 | ||
1301 | free_hash: | |
1302 | free_ftrace_hash(new_hash); | |
1303 | return NULL; | |
1304 | } | |
1305 | ||
41fb61c2 SR |
1306 | static void |
1307 | ftrace_hash_rec_disable(struct ftrace_ops *ops, int filter_hash); | |
1308 | static void | |
1309 | ftrace_hash_rec_enable(struct ftrace_ops *ops, int filter_hash); | |
1310 | ||
33dc9b12 | 1311 | static int |
41fb61c2 SR |
1312 | ftrace_hash_move(struct ftrace_ops *ops, int enable, |
1313 | struct ftrace_hash **dst, struct ftrace_hash *src) | |
33dc9b12 SR |
1314 | { |
1315 | struct ftrace_func_entry *entry; | |
b67bfe0d | 1316 | struct hlist_node *tn; |
33dc9b12 | 1317 | struct hlist_head *hhd; |
07fd5515 SR |
1318 | struct ftrace_hash *old_hash; |
1319 | struct ftrace_hash *new_hash; | |
33dc9b12 SR |
1320 | unsigned long key; |
1321 | int size = src->count; | |
1322 | int bits = 0; | |
41fb61c2 | 1323 | int ret; |
33dc9b12 SR |
1324 | int i; |
1325 | ||
41fb61c2 SR |
1326 | /* |
1327 | * Remove the current set, update the hash and add | |
1328 | * them back. | |
1329 | */ | |
1330 | ftrace_hash_rec_disable(ops, enable); | |
1331 | ||
33dc9b12 SR |
1332 | /* |
1333 | * If the new source is empty, just free dst and assign it | |
1334 | * the empty_hash. | |
1335 | */ | |
1336 | if (!src->count) { | |
07fd5515 SR |
1337 | free_ftrace_hash_rcu(*dst); |
1338 | rcu_assign_pointer(*dst, EMPTY_HASH); | |
d4d34b98 SR |
1339 | /* still need to update the function records */ |
1340 | ret = 0; | |
1341 | goto out; | |
33dc9b12 SR |
1342 | } |
1343 | ||
33dc9b12 SR |
1344 | /* |
1345 | * Make the hash size about 1/2 the # found | |
1346 | */ | |
1347 | for (size /= 2; size; size >>= 1) | |
1348 | bits++; | |
1349 | ||
1350 | /* Don't allocate too much */ | |
1351 | if (bits > FTRACE_HASH_MAX_BITS) | |
1352 | bits = FTRACE_HASH_MAX_BITS; | |
1353 | ||
41fb61c2 | 1354 | ret = -ENOMEM; |
07fd5515 SR |
1355 | new_hash = alloc_ftrace_hash(bits); |
1356 | if (!new_hash) | |
41fb61c2 | 1357 | goto out; |
33dc9b12 SR |
1358 | |
1359 | size = 1 << src->size_bits; | |
1360 | for (i = 0; i < size; i++) { | |
1361 | hhd = &src->buckets[i]; | |
b67bfe0d | 1362 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) { |
33dc9b12 SR |
1363 | if (bits > 0) |
1364 | key = hash_long(entry->ip, bits); | |
1365 | else | |
1366 | key = 0; | |
1367 | remove_hash_entry(src, entry); | |
07fd5515 | 1368 | __add_hash_entry(new_hash, entry); |
33dc9b12 SR |
1369 | } |
1370 | } | |
1371 | ||
07fd5515 SR |
1372 | old_hash = *dst; |
1373 | rcu_assign_pointer(*dst, new_hash); | |
1374 | free_ftrace_hash_rcu(old_hash); | |
1375 | ||
41fb61c2 SR |
1376 | ret = 0; |
1377 | out: | |
1378 | /* | |
1379 | * Enable regardless of ret: | |
1380 | * On success, we enable the new hash. | |
1381 | * On failure, we re-enable the original hash. | |
1382 | */ | |
1383 | ftrace_hash_rec_enable(ops, enable); | |
1384 | ||
1385 | return ret; | |
33dc9b12 SR |
1386 | } |
1387 | ||
b848914c SR |
1388 | /* |
1389 | * Test the hashes for this ops to see if we want to call | |
1390 | * the ops->func or not. | |
1391 | * | |
1392 | * It's a match if the ip is in the ops->filter_hash or | |
1393 | * the filter_hash does not exist or is empty, | |
1394 | * AND | |
1395 | * the ip is not in the ops->notrace_hash. | |
cdbe61bf SR |
1396 | * |
1397 | * This needs to be called with preemption disabled as | |
1398 | * the hashes are freed with call_rcu_sched(). | |
b848914c SR |
1399 | */ |
1400 | static int | |
1401 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip) | |
1402 | { | |
1403 | struct ftrace_hash *filter_hash; | |
1404 | struct ftrace_hash *notrace_hash; | |
1405 | int ret; | |
1406 | ||
b848914c SR |
1407 | filter_hash = rcu_dereference_raw(ops->filter_hash); |
1408 | notrace_hash = rcu_dereference_raw(ops->notrace_hash); | |
1409 | ||
06a51d93 | 1410 | if ((ftrace_hash_empty(filter_hash) || |
b848914c | 1411 | ftrace_lookup_ip(filter_hash, ip)) && |
06a51d93 | 1412 | (ftrace_hash_empty(notrace_hash) || |
b848914c SR |
1413 | !ftrace_lookup_ip(notrace_hash, ip))) |
1414 | ret = 1; | |
1415 | else | |
1416 | ret = 0; | |
b848914c SR |
1417 | |
1418 | return ret; | |
1419 | } | |
1420 | ||
493762fc SR |
1421 | /* |
1422 | * This is a double for. Do not use 'break' to break out of the loop, | |
1423 | * you must use a goto. | |
1424 | */ | |
1425 | #define do_for_each_ftrace_rec(pg, rec) \ | |
1426 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
1427 | int _____i; \ | |
1428 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
1429 | rec = &pg->records[_____i]; | |
1430 | ||
1431 | #define while_for_each_ftrace_rec() \ | |
1432 | } \ | |
1433 | } | |
1434 | ||
5855fead SR |
1435 | |
1436 | static int ftrace_cmp_recs(const void *a, const void *b) | |
1437 | { | |
a650e02a SR |
1438 | const struct dyn_ftrace *key = a; |
1439 | const struct dyn_ftrace *rec = b; | |
5855fead | 1440 | |
a650e02a | 1441 | if (key->flags < rec->ip) |
5855fead | 1442 | return -1; |
a650e02a SR |
1443 | if (key->ip >= rec->ip + MCOUNT_INSN_SIZE) |
1444 | return 1; | |
5855fead SR |
1445 | return 0; |
1446 | } | |
1447 | ||
f0cf973a | 1448 | static unsigned long ftrace_location_range(unsigned long start, unsigned long end) |
c88fd863 SR |
1449 | { |
1450 | struct ftrace_page *pg; | |
1451 | struct dyn_ftrace *rec; | |
5855fead | 1452 | struct dyn_ftrace key; |
c88fd863 | 1453 | |
a650e02a SR |
1454 | key.ip = start; |
1455 | key.flags = end; /* overload flags, as it is unsigned long */ | |
5855fead SR |
1456 | |
1457 | for (pg = ftrace_pages_start; pg; pg = pg->next) { | |
a650e02a SR |
1458 | if (end < pg->records[0].ip || |
1459 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) | |
9644302e | 1460 | continue; |
5855fead SR |
1461 | rec = bsearch(&key, pg->records, pg->index, |
1462 | sizeof(struct dyn_ftrace), | |
1463 | ftrace_cmp_recs); | |
1464 | if (rec) | |
f0cf973a | 1465 | return rec->ip; |
5855fead | 1466 | } |
c88fd863 SR |
1467 | |
1468 | return 0; | |
1469 | } | |
1470 | ||
a650e02a SR |
1471 | /** |
1472 | * ftrace_location - return true if the ip giving is a traced location | |
1473 | * @ip: the instruction pointer to check | |
1474 | * | |
f0cf973a | 1475 | * Returns rec->ip if @ip given is a pointer to a ftrace location. |
a650e02a SR |
1476 | * That is, the instruction that is either a NOP or call to |
1477 | * the function tracer. It checks the ftrace internal tables to | |
1478 | * determine if the address belongs or not. | |
1479 | */ | |
f0cf973a | 1480 | unsigned long ftrace_location(unsigned long ip) |
a650e02a SR |
1481 | { |
1482 | return ftrace_location_range(ip, ip); | |
1483 | } | |
1484 | ||
1485 | /** | |
1486 | * ftrace_text_reserved - return true if range contains an ftrace location | |
1487 | * @start: start of range to search | |
1488 | * @end: end of range to search (inclusive). @end points to the last byte to check. | |
1489 | * | |
1490 | * Returns 1 if @start and @end contains a ftrace location. | |
1491 | * That is, the instruction that is either a NOP or call to | |
1492 | * the function tracer. It checks the ftrace internal tables to | |
1493 | * determine if the address belongs or not. | |
1494 | */ | |
1495 | int ftrace_text_reserved(void *start, void *end) | |
1496 | { | |
f0cf973a SR |
1497 | unsigned long ret; |
1498 | ||
1499 | ret = ftrace_location_range((unsigned long)start, | |
1500 | (unsigned long)end); | |
1501 | ||
1502 | return (int)!!ret; | |
a650e02a SR |
1503 | } |
1504 | ||
ed926f9b SR |
1505 | static void __ftrace_hash_rec_update(struct ftrace_ops *ops, |
1506 | int filter_hash, | |
1507 | bool inc) | |
1508 | { | |
1509 | struct ftrace_hash *hash; | |
1510 | struct ftrace_hash *other_hash; | |
1511 | struct ftrace_page *pg; | |
1512 | struct dyn_ftrace *rec; | |
1513 | int count = 0; | |
1514 | int all = 0; | |
1515 | ||
1516 | /* Only update if the ops has been registered */ | |
1517 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
1518 | return; | |
1519 | ||
1520 | /* | |
1521 | * In the filter_hash case: | |
1522 | * If the count is zero, we update all records. | |
1523 | * Otherwise we just update the items in the hash. | |
1524 | * | |
1525 | * In the notrace_hash case: | |
1526 | * We enable the update in the hash. | |
1527 | * As disabling notrace means enabling the tracing, | |
1528 | * and enabling notrace means disabling, the inc variable | |
1529 | * gets inversed. | |
1530 | */ | |
1531 | if (filter_hash) { | |
1532 | hash = ops->filter_hash; | |
1533 | other_hash = ops->notrace_hash; | |
06a51d93 | 1534 | if (ftrace_hash_empty(hash)) |
ed926f9b SR |
1535 | all = 1; |
1536 | } else { | |
1537 | inc = !inc; | |
1538 | hash = ops->notrace_hash; | |
1539 | other_hash = ops->filter_hash; | |
1540 | /* | |
1541 | * If the notrace hash has no items, | |
1542 | * then there's nothing to do. | |
1543 | */ | |
06a51d93 | 1544 | if (ftrace_hash_empty(hash)) |
ed926f9b SR |
1545 | return; |
1546 | } | |
1547 | ||
1548 | do_for_each_ftrace_rec(pg, rec) { | |
1549 | int in_other_hash = 0; | |
1550 | int in_hash = 0; | |
1551 | int match = 0; | |
1552 | ||
1553 | if (all) { | |
1554 | /* | |
1555 | * Only the filter_hash affects all records. | |
1556 | * Update if the record is not in the notrace hash. | |
1557 | */ | |
b848914c | 1558 | if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip)) |
ed926f9b SR |
1559 | match = 1; |
1560 | } else { | |
06a51d93 SR |
1561 | in_hash = !!ftrace_lookup_ip(hash, rec->ip); |
1562 | in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip); | |
ed926f9b SR |
1563 | |
1564 | /* | |
1565 | * | |
1566 | */ | |
1567 | if (filter_hash && in_hash && !in_other_hash) | |
1568 | match = 1; | |
1569 | else if (!filter_hash && in_hash && | |
06a51d93 | 1570 | (in_other_hash || ftrace_hash_empty(other_hash))) |
ed926f9b SR |
1571 | match = 1; |
1572 | } | |
1573 | if (!match) | |
1574 | continue; | |
1575 | ||
1576 | if (inc) { | |
1577 | rec->flags++; | |
1578 | if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == FTRACE_REF_MAX)) | |
1579 | return; | |
08f6fba5 SR |
1580 | /* |
1581 | * If any ops wants regs saved for this function | |
1582 | * then all ops will get saved regs. | |
1583 | */ | |
1584 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) | |
1585 | rec->flags |= FTRACE_FL_REGS; | |
ed926f9b SR |
1586 | } else { |
1587 | if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == 0)) | |
1588 | return; | |
1589 | rec->flags--; | |
1590 | } | |
1591 | count++; | |
1592 | /* Shortcut, if we handled all records, we are done. */ | |
1593 | if (!all && count == hash->count) | |
1594 | return; | |
1595 | } while_for_each_ftrace_rec(); | |
1596 | } | |
1597 | ||
1598 | static void ftrace_hash_rec_disable(struct ftrace_ops *ops, | |
1599 | int filter_hash) | |
1600 | { | |
1601 | __ftrace_hash_rec_update(ops, filter_hash, 0); | |
1602 | } | |
1603 | ||
1604 | static void ftrace_hash_rec_enable(struct ftrace_ops *ops, | |
1605 | int filter_hash) | |
1606 | { | |
1607 | __ftrace_hash_rec_update(ops, filter_hash, 1); | |
1608 | } | |
1609 | ||
b17e8a37 SR |
1610 | static void print_ip_ins(const char *fmt, unsigned char *p) |
1611 | { | |
1612 | int i; | |
1613 | ||
1614 | printk(KERN_CONT "%s", fmt); | |
1615 | ||
1616 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
1617 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
1618 | } | |
1619 | ||
c88fd863 SR |
1620 | /** |
1621 | * ftrace_bug - report and shutdown function tracer | |
1622 | * @failed: The failed type (EFAULT, EINVAL, EPERM) | |
1623 | * @ip: The address that failed | |
1624 | * | |
1625 | * The arch code that enables or disables the function tracing | |
1626 | * can call ftrace_bug() when it has detected a problem in | |
1627 | * modifying the code. @failed should be one of either: | |
1628 | * EFAULT - if the problem happens on reading the @ip address | |
1629 | * EINVAL - if what is read at @ip is not what was expected | |
1630 | * EPERM - if the problem happens on writting to the @ip address | |
1631 | */ | |
1632 | void ftrace_bug(int failed, unsigned long ip) | |
b17e8a37 SR |
1633 | { |
1634 | switch (failed) { | |
1635 | case -EFAULT: | |
1636 | FTRACE_WARN_ON_ONCE(1); | |
1637 | pr_info("ftrace faulted on modifying "); | |
1638 | print_ip_sym(ip); | |
1639 | break; | |
1640 | case -EINVAL: | |
1641 | FTRACE_WARN_ON_ONCE(1); | |
1642 | pr_info("ftrace failed to modify "); | |
1643 | print_ip_sym(ip); | |
b17e8a37 | 1644 | print_ip_ins(" actual: ", (unsigned char *)ip); |
b17e8a37 SR |
1645 | printk(KERN_CONT "\n"); |
1646 | break; | |
1647 | case -EPERM: | |
1648 | FTRACE_WARN_ON_ONCE(1); | |
1649 | pr_info("ftrace faulted on writing "); | |
1650 | print_ip_sym(ip); | |
1651 | break; | |
1652 | default: | |
1653 | FTRACE_WARN_ON_ONCE(1); | |
1654 | pr_info("ftrace faulted on unknown error "); | |
1655 | print_ip_sym(ip); | |
1656 | } | |
1657 | } | |
1658 | ||
c88fd863 | 1659 | static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update) |
5072c59f | 1660 | { |
64fbcd16 | 1661 | unsigned long flag = 0UL; |
e7d3737e | 1662 | |
982c350b | 1663 | /* |
30fb6aa7 | 1664 | * If we are updating calls: |
982c350b | 1665 | * |
ed926f9b SR |
1666 | * If the record has a ref count, then we need to enable it |
1667 | * because someone is using it. | |
982c350b | 1668 | * |
ed926f9b SR |
1669 | * Otherwise we make sure its disabled. |
1670 | * | |
30fb6aa7 | 1671 | * If we are disabling calls, then disable all records that |
ed926f9b | 1672 | * are enabled. |
982c350b | 1673 | */ |
c88fd863 | 1674 | if (enable && (rec->flags & ~FTRACE_FL_MASK)) |
ed926f9b | 1675 | flag = FTRACE_FL_ENABLED; |
982c350b | 1676 | |
08f6fba5 SR |
1677 | /* |
1678 | * If enabling and the REGS flag does not match the REGS_EN, then | |
1679 | * do not ignore this record. Set flags to fail the compare against | |
1680 | * ENABLED. | |
1681 | */ | |
1682 | if (flag && | |
1683 | (!(rec->flags & FTRACE_FL_REGS) != !(rec->flags & FTRACE_FL_REGS_EN))) | |
1684 | flag |= FTRACE_FL_REGS; | |
1685 | ||
64fbcd16 XG |
1686 | /* If the state of this record hasn't changed, then do nothing */ |
1687 | if ((rec->flags & FTRACE_FL_ENABLED) == flag) | |
c88fd863 | 1688 | return FTRACE_UPDATE_IGNORE; |
982c350b | 1689 | |
64fbcd16 | 1690 | if (flag) { |
08f6fba5 SR |
1691 | /* Save off if rec is being enabled (for return value) */ |
1692 | flag ^= rec->flags & FTRACE_FL_ENABLED; | |
1693 | ||
1694 | if (update) { | |
c88fd863 | 1695 | rec->flags |= FTRACE_FL_ENABLED; |
08f6fba5 SR |
1696 | if (flag & FTRACE_FL_REGS) { |
1697 | if (rec->flags & FTRACE_FL_REGS) | |
1698 | rec->flags |= FTRACE_FL_REGS_EN; | |
1699 | else | |
1700 | rec->flags &= ~FTRACE_FL_REGS_EN; | |
1701 | } | |
1702 | } | |
1703 | ||
1704 | /* | |
1705 | * If this record is being updated from a nop, then | |
1706 | * return UPDATE_MAKE_CALL. | |
1707 | * Otherwise, if the EN flag is set, then return | |
1708 | * UPDATE_MODIFY_CALL_REGS to tell the caller to convert | |
1709 | * from the non-save regs, to a save regs function. | |
1710 | * Otherwise, | |
1711 | * return UPDATE_MODIFY_CALL to tell the caller to convert | |
1712 | * from the save regs, to a non-save regs function. | |
1713 | */ | |
1714 | if (flag & FTRACE_FL_ENABLED) | |
1715 | return FTRACE_UPDATE_MAKE_CALL; | |
1716 | else if (rec->flags & FTRACE_FL_REGS_EN) | |
1717 | return FTRACE_UPDATE_MODIFY_CALL_REGS; | |
1718 | else | |
1719 | return FTRACE_UPDATE_MODIFY_CALL; | |
c88fd863 SR |
1720 | } |
1721 | ||
08f6fba5 SR |
1722 | if (update) { |
1723 | /* If there's no more users, clear all flags */ | |
1724 | if (!(rec->flags & ~FTRACE_FL_MASK)) | |
1725 | rec->flags = 0; | |
1726 | else | |
1727 | /* Just disable the record (keep REGS state) */ | |
1728 | rec->flags &= ~FTRACE_FL_ENABLED; | |
1729 | } | |
c88fd863 SR |
1730 | |
1731 | return FTRACE_UPDATE_MAKE_NOP; | |
1732 | } | |
1733 | ||
1734 | /** | |
1735 | * ftrace_update_record, set a record that now is tracing or not | |
1736 | * @rec: the record to update | |
1737 | * @enable: set to 1 if the record is tracing, zero to force disable | |
1738 | * | |
1739 | * The records that represent all functions that can be traced need | |
1740 | * to be updated when tracing has been enabled. | |
1741 | */ | |
1742 | int ftrace_update_record(struct dyn_ftrace *rec, int enable) | |
1743 | { | |
1744 | return ftrace_check_record(rec, enable, 1); | |
1745 | } | |
1746 | ||
1747 | /** | |
1748 | * ftrace_test_record, check if the record has been enabled or not | |
1749 | * @rec: the record to test | |
1750 | * @enable: set to 1 to check if enabled, 0 if it is disabled | |
1751 | * | |
1752 | * The arch code may need to test if a record is already set to | |
1753 | * tracing to determine how to modify the function code that it | |
1754 | * represents. | |
1755 | */ | |
1756 | int ftrace_test_record(struct dyn_ftrace *rec, int enable) | |
1757 | { | |
1758 | return ftrace_check_record(rec, enable, 0); | |
1759 | } | |
1760 | ||
1761 | static int | |
1762 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) | |
1763 | { | |
08f6fba5 | 1764 | unsigned long ftrace_old_addr; |
c88fd863 SR |
1765 | unsigned long ftrace_addr; |
1766 | int ret; | |
1767 | ||
c88fd863 SR |
1768 | ret = ftrace_update_record(rec, enable); |
1769 | ||
08f6fba5 SR |
1770 | if (rec->flags & FTRACE_FL_REGS) |
1771 | ftrace_addr = (unsigned long)FTRACE_REGS_ADDR; | |
1772 | else | |
1773 | ftrace_addr = (unsigned long)FTRACE_ADDR; | |
1774 | ||
c88fd863 SR |
1775 | switch (ret) { |
1776 | case FTRACE_UPDATE_IGNORE: | |
1777 | return 0; | |
1778 | ||
1779 | case FTRACE_UPDATE_MAKE_CALL: | |
64fbcd16 | 1780 | return ftrace_make_call(rec, ftrace_addr); |
c88fd863 SR |
1781 | |
1782 | case FTRACE_UPDATE_MAKE_NOP: | |
1783 | return ftrace_make_nop(NULL, rec, ftrace_addr); | |
08f6fba5 SR |
1784 | |
1785 | case FTRACE_UPDATE_MODIFY_CALL_REGS: | |
1786 | case FTRACE_UPDATE_MODIFY_CALL: | |
1787 | if (rec->flags & FTRACE_FL_REGS) | |
1788 | ftrace_old_addr = (unsigned long)FTRACE_ADDR; | |
1789 | else | |
1790 | ftrace_old_addr = (unsigned long)FTRACE_REGS_ADDR; | |
1791 | ||
1792 | return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr); | |
5072c59f SR |
1793 | } |
1794 | ||
c88fd863 | 1795 | return -1; /* unknow ftrace bug */ |
5072c59f SR |
1796 | } |
1797 | ||
e4f5d544 | 1798 | void __weak ftrace_replace_code(int enable) |
3c1720f0 | 1799 | { |
3c1720f0 SR |
1800 | struct dyn_ftrace *rec; |
1801 | struct ftrace_page *pg; | |
6a24a244 | 1802 | int failed; |
3c1720f0 | 1803 | |
45a4a237 SR |
1804 | if (unlikely(ftrace_disabled)) |
1805 | return; | |
1806 | ||
265c831c | 1807 | do_for_each_ftrace_rec(pg, rec) { |
e4f5d544 | 1808 | failed = __ftrace_replace_code(rec, enable); |
fa9d13cf | 1809 | if (failed) { |
3279ba37 SR |
1810 | ftrace_bug(failed, rec->ip); |
1811 | /* Stop processing */ | |
1812 | return; | |
3c1720f0 | 1813 | } |
265c831c | 1814 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
1815 | } |
1816 | ||
c88fd863 SR |
1817 | struct ftrace_rec_iter { |
1818 | struct ftrace_page *pg; | |
1819 | int index; | |
1820 | }; | |
1821 | ||
1822 | /** | |
1823 | * ftrace_rec_iter_start, start up iterating over traced functions | |
1824 | * | |
1825 | * Returns an iterator handle that is used to iterate over all | |
1826 | * the records that represent address locations where functions | |
1827 | * are traced. | |
1828 | * | |
1829 | * May return NULL if no records are available. | |
1830 | */ | |
1831 | struct ftrace_rec_iter *ftrace_rec_iter_start(void) | |
1832 | { | |
1833 | /* | |
1834 | * We only use a single iterator. | |
1835 | * Protected by the ftrace_lock mutex. | |
1836 | */ | |
1837 | static struct ftrace_rec_iter ftrace_rec_iter; | |
1838 | struct ftrace_rec_iter *iter = &ftrace_rec_iter; | |
1839 | ||
1840 | iter->pg = ftrace_pages_start; | |
1841 | iter->index = 0; | |
1842 | ||
1843 | /* Could have empty pages */ | |
1844 | while (iter->pg && !iter->pg->index) | |
1845 | iter->pg = iter->pg->next; | |
1846 | ||
1847 | if (!iter->pg) | |
1848 | return NULL; | |
1849 | ||
1850 | return iter; | |
1851 | } | |
1852 | ||
1853 | /** | |
1854 | * ftrace_rec_iter_next, get the next record to process. | |
1855 | * @iter: The handle to the iterator. | |
1856 | * | |
1857 | * Returns the next iterator after the given iterator @iter. | |
1858 | */ | |
1859 | struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter) | |
1860 | { | |
1861 | iter->index++; | |
1862 | ||
1863 | if (iter->index >= iter->pg->index) { | |
1864 | iter->pg = iter->pg->next; | |
1865 | iter->index = 0; | |
1866 | ||
1867 | /* Could have empty pages */ | |
1868 | while (iter->pg && !iter->pg->index) | |
1869 | iter->pg = iter->pg->next; | |
1870 | } | |
1871 | ||
1872 | if (!iter->pg) | |
1873 | return NULL; | |
1874 | ||
1875 | return iter; | |
1876 | } | |
1877 | ||
1878 | /** | |
1879 | * ftrace_rec_iter_record, get the record at the iterator location | |
1880 | * @iter: The current iterator location | |
1881 | * | |
1882 | * Returns the record that the current @iter is at. | |
1883 | */ | |
1884 | struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter) | |
1885 | { | |
1886 | return &iter->pg->records[iter->index]; | |
1887 | } | |
1888 | ||
492a7ea5 | 1889 | static int |
31e88909 | 1890 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 SR |
1891 | { |
1892 | unsigned long ip; | |
593eb8a2 | 1893 | int ret; |
3c1720f0 SR |
1894 | |
1895 | ip = rec->ip; | |
1896 | ||
45a4a237 SR |
1897 | if (unlikely(ftrace_disabled)) |
1898 | return 0; | |
1899 | ||
25aac9dc | 1900 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
593eb8a2 | 1901 | if (ret) { |
31e88909 | 1902 | ftrace_bug(ret, ip); |
492a7ea5 | 1903 | return 0; |
37ad5084 | 1904 | } |
492a7ea5 | 1905 | return 1; |
3c1720f0 SR |
1906 | } |
1907 | ||
000ab691 SR |
1908 | /* |
1909 | * archs can override this function if they must do something | |
1910 | * before the modifying code is performed. | |
1911 | */ | |
1912 | int __weak ftrace_arch_code_modify_prepare(void) | |
1913 | { | |
1914 | return 0; | |
1915 | } | |
1916 | ||
1917 | /* | |
1918 | * archs can override this function if they must do something | |
1919 | * after the modifying code is performed. | |
1920 | */ | |
1921 | int __weak ftrace_arch_code_modify_post_process(void) | |
1922 | { | |
1923 | return 0; | |
1924 | } | |
1925 | ||
8ed3e2cf | 1926 | void ftrace_modify_all_code(int command) |
3d083395 | 1927 | { |
8ed3e2cf | 1928 | if (command & FTRACE_UPDATE_CALLS) |
d61f82d0 | 1929 | ftrace_replace_code(1); |
8ed3e2cf | 1930 | else if (command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
1931 | ftrace_replace_code(0); |
1932 | ||
8ed3e2cf | 1933 | if (command & FTRACE_UPDATE_TRACE_FUNC) |
d61f82d0 SR |
1934 | ftrace_update_ftrace_func(ftrace_trace_function); |
1935 | ||
8ed3e2cf | 1936 | if (command & FTRACE_START_FUNC_RET) |
5a45cfe1 | 1937 | ftrace_enable_ftrace_graph_caller(); |
8ed3e2cf | 1938 | else if (command & FTRACE_STOP_FUNC_RET) |
5a45cfe1 | 1939 | ftrace_disable_ftrace_graph_caller(); |
8ed3e2cf SR |
1940 | } |
1941 | ||
1942 | static int __ftrace_modify_code(void *data) | |
1943 | { | |
1944 | int *command = data; | |
1945 | ||
1946 | ftrace_modify_all_code(*command); | |
5a45cfe1 | 1947 | |
d61f82d0 | 1948 | return 0; |
3d083395 SR |
1949 | } |
1950 | ||
c88fd863 SR |
1951 | /** |
1952 | * ftrace_run_stop_machine, go back to the stop machine method | |
1953 | * @command: The command to tell ftrace what to do | |
1954 | * | |
1955 | * If an arch needs to fall back to the stop machine method, the | |
1956 | * it can call this function. | |
1957 | */ | |
1958 | void ftrace_run_stop_machine(int command) | |
1959 | { | |
1960 | stop_machine(__ftrace_modify_code, &command, NULL); | |
1961 | } | |
1962 | ||
1963 | /** | |
1964 | * arch_ftrace_update_code, modify the code to trace or not trace | |
1965 | * @command: The command that needs to be done | |
1966 | * | |
1967 | * Archs can override this function if it does not need to | |
1968 | * run stop_machine() to modify code. | |
1969 | */ | |
1970 | void __weak arch_ftrace_update_code(int command) | |
1971 | { | |
1972 | ftrace_run_stop_machine(command); | |
1973 | } | |
1974 | ||
e309b41d | 1975 | static void ftrace_run_update_code(int command) |
3d083395 | 1976 | { |
000ab691 SR |
1977 | int ret; |
1978 | ||
1979 | ret = ftrace_arch_code_modify_prepare(); | |
1980 | FTRACE_WARN_ON(ret); | |
1981 | if (ret) | |
1982 | return; | |
c88fd863 SR |
1983 | /* |
1984 | * Do not call function tracer while we update the code. | |
1985 | * We are in stop machine. | |
1986 | */ | |
1987 | function_trace_stop++; | |
000ab691 | 1988 | |
c88fd863 SR |
1989 | /* |
1990 | * By default we use stop_machine() to modify the code. | |
1991 | * But archs can do what ever they want as long as it | |
1992 | * is safe. The stop_machine() is the safest, but also | |
1993 | * produces the most overhead. | |
1994 | */ | |
1995 | arch_ftrace_update_code(command); | |
1996 | ||
c88fd863 | 1997 | function_trace_stop--; |
000ab691 SR |
1998 | |
1999 | ret = ftrace_arch_code_modify_post_process(); | |
2000 | FTRACE_WARN_ON(ret); | |
3d083395 SR |
2001 | } |
2002 | ||
d61f82d0 | 2003 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 2004 | static int ftrace_start_up; |
b848914c | 2005 | static int global_start_up; |
df4fc315 SR |
2006 | |
2007 | static void ftrace_startup_enable(int command) | |
2008 | { | |
2009 | if (saved_ftrace_func != ftrace_trace_function) { | |
2010 | saved_ftrace_func = ftrace_trace_function; | |
2011 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2012 | } | |
2013 | ||
2014 | if (!command || !ftrace_enabled) | |
2015 | return; | |
2016 | ||
2017 | ftrace_run_update_code(command); | |
2018 | } | |
d61f82d0 | 2019 | |
a1cd6173 | 2020 | static int ftrace_startup(struct ftrace_ops *ops, int command) |
3d083395 | 2021 | { |
b848914c SR |
2022 | bool hash_enable = true; |
2023 | ||
4eebcc81 | 2024 | if (unlikely(ftrace_disabled)) |
a1cd6173 | 2025 | return -ENODEV; |
4eebcc81 | 2026 | |
60a7ecf4 | 2027 | ftrace_start_up++; |
30fb6aa7 | 2028 | command |= FTRACE_UPDATE_CALLS; |
d61f82d0 | 2029 | |
b848914c SR |
2030 | /* ops marked global share the filter hashes */ |
2031 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { | |
2032 | ops = &global_ops; | |
2033 | /* Don't update hash if global is already set */ | |
2034 | if (global_start_up) | |
2035 | hash_enable = false; | |
2036 | global_start_up++; | |
2037 | } | |
2038 | ||
ed926f9b | 2039 | ops->flags |= FTRACE_OPS_FL_ENABLED; |
b848914c | 2040 | if (hash_enable) |
ed926f9b SR |
2041 | ftrace_hash_rec_enable(ops, 1); |
2042 | ||
df4fc315 | 2043 | ftrace_startup_enable(command); |
a1cd6173 SR |
2044 | |
2045 | return 0; | |
3d083395 SR |
2046 | } |
2047 | ||
bd69c30b | 2048 | static void ftrace_shutdown(struct ftrace_ops *ops, int command) |
3d083395 | 2049 | { |
b848914c SR |
2050 | bool hash_disable = true; |
2051 | ||
4eebcc81 SR |
2052 | if (unlikely(ftrace_disabled)) |
2053 | return; | |
2054 | ||
60a7ecf4 | 2055 | ftrace_start_up--; |
9ea1a153 FW |
2056 | /* |
2057 | * Just warn in case of unbalance, no need to kill ftrace, it's not | |
2058 | * critical but the ftrace_call callers may be never nopped again after | |
2059 | * further ftrace uses. | |
2060 | */ | |
2061 | WARN_ON_ONCE(ftrace_start_up < 0); | |
2062 | ||
b848914c SR |
2063 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
2064 | ops = &global_ops; | |
2065 | global_start_up--; | |
2066 | WARN_ON_ONCE(global_start_up < 0); | |
2067 | /* Don't update hash if global still has users */ | |
2068 | if (global_start_up) { | |
2069 | WARN_ON_ONCE(!ftrace_start_up); | |
2070 | hash_disable = false; | |
2071 | } | |
2072 | } | |
2073 | ||
2074 | if (hash_disable) | |
ed926f9b SR |
2075 | ftrace_hash_rec_disable(ops, 1); |
2076 | ||
b848914c | 2077 | if (ops != &global_ops || !global_start_up) |
ed926f9b | 2078 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; |
b848914c | 2079 | |
30fb6aa7 | 2080 | command |= FTRACE_UPDATE_CALLS; |
3d083395 | 2081 | |
d61f82d0 SR |
2082 | if (saved_ftrace_func != ftrace_trace_function) { |
2083 | saved_ftrace_func = ftrace_trace_function; | |
2084 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2085 | } | |
3d083395 | 2086 | |
d61f82d0 | 2087 | if (!command || !ftrace_enabled) |
e6ea44e9 | 2088 | return; |
d61f82d0 SR |
2089 | |
2090 | ftrace_run_update_code(command); | |
3d083395 SR |
2091 | } |
2092 | ||
e309b41d | 2093 | static void ftrace_startup_sysctl(void) |
b0fc494f | 2094 | { |
4eebcc81 SR |
2095 | if (unlikely(ftrace_disabled)) |
2096 | return; | |
2097 | ||
d61f82d0 SR |
2098 | /* Force update next time */ |
2099 | saved_ftrace_func = NULL; | |
60a7ecf4 SR |
2100 | /* ftrace_start_up is true if we want ftrace running */ |
2101 | if (ftrace_start_up) | |
30fb6aa7 | 2102 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); |
b0fc494f SR |
2103 | } |
2104 | ||
e309b41d | 2105 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 2106 | { |
4eebcc81 SR |
2107 | if (unlikely(ftrace_disabled)) |
2108 | return; | |
2109 | ||
60a7ecf4 SR |
2110 | /* ftrace_start_up is true if ftrace is running */ |
2111 | if (ftrace_start_up) | |
79e406d7 | 2112 | ftrace_run_update_code(FTRACE_DISABLE_CALLS); |
b0fc494f SR |
2113 | } |
2114 | ||
3d083395 SR |
2115 | static cycle_t ftrace_update_time; |
2116 | static unsigned long ftrace_update_cnt; | |
2117 | unsigned long ftrace_update_tot_cnt; | |
2118 | ||
f7bc8b61 SR |
2119 | static int ops_traces_mod(struct ftrace_ops *ops) |
2120 | { | |
2121 | struct ftrace_hash *hash; | |
2122 | ||
2123 | hash = ops->filter_hash; | |
06a51d93 | 2124 | return ftrace_hash_empty(hash); |
f7bc8b61 SR |
2125 | } |
2126 | ||
31e88909 | 2127 | static int ftrace_update_code(struct module *mod) |
3d083395 | 2128 | { |
85ae32ae | 2129 | struct ftrace_page *pg; |
e94142a6 | 2130 | struct dyn_ftrace *p; |
f22f9a89 | 2131 | cycle_t start, stop; |
f7bc8b61 | 2132 | unsigned long ref = 0; |
85ae32ae | 2133 | int i; |
f7bc8b61 SR |
2134 | |
2135 | /* | |
2136 | * When adding a module, we need to check if tracers are | |
2137 | * currently enabled and if they are set to trace all functions. | |
2138 | * If they are, we need to enable the module functions as well | |
2139 | * as update the reference counts for those function records. | |
2140 | */ | |
2141 | if (mod) { | |
2142 | struct ftrace_ops *ops; | |
2143 | ||
2144 | for (ops = ftrace_ops_list; | |
2145 | ops != &ftrace_list_end; ops = ops->next) { | |
2146 | if (ops->flags & FTRACE_OPS_FL_ENABLED && | |
2147 | ops_traces_mod(ops)) | |
2148 | ref++; | |
2149 | } | |
2150 | } | |
3d083395 | 2151 | |
750ed1a4 | 2152 | start = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
2153 | ftrace_update_cnt = 0; |
2154 | ||
85ae32ae | 2155 | for (pg = ftrace_new_pgs; pg; pg = pg->next) { |
3d083395 | 2156 | |
85ae32ae SR |
2157 | for (i = 0; i < pg->index; i++) { |
2158 | /* If something went wrong, bail without enabling anything */ | |
2159 | if (unlikely(ftrace_disabled)) | |
2160 | return -1; | |
f22f9a89 | 2161 | |
85ae32ae SR |
2162 | p = &pg->records[i]; |
2163 | p->flags = ref; | |
f22f9a89 | 2164 | |
85ae32ae SR |
2165 | /* |
2166 | * Do the initial record conversion from mcount jump | |
2167 | * to the NOP instructions. | |
2168 | */ | |
2169 | if (!ftrace_code_disable(mod, p)) | |
2170 | break; | |
5cb084bb | 2171 | |
85ae32ae | 2172 | ftrace_update_cnt++; |
5cb084bb | 2173 | |
85ae32ae SR |
2174 | /* |
2175 | * If the tracing is enabled, go ahead and enable the record. | |
2176 | * | |
2177 | * The reason not to enable the record immediatelly is the | |
2178 | * inherent check of ftrace_make_nop/ftrace_make_call for | |
2179 | * correct previous instructions. Making first the NOP | |
2180 | * conversion puts the module to the correct state, thus | |
2181 | * passing the ftrace_make_call check. | |
2182 | */ | |
2183 | if (ftrace_start_up && ref) { | |
2184 | int failed = __ftrace_replace_code(p, 1); | |
2185 | if (failed) | |
2186 | ftrace_bug(failed, p->ip); | |
2187 | } | |
5cb084bb | 2188 | } |
3d083395 SR |
2189 | } |
2190 | ||
85ae32ae SR |
2191 | ftrace_new_pgs = NULL; |
2192 | ||
750ed1a4 | 2193 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
2194 | ftrace_update_time = stop - start; |
2195 | ftrace_update_tot_cnt += ftrace_update_cnt; | |
2196 | ||
16444a8a ACM |
2197 | return 0; |
2198 | } | |
2199 | ||
a7900875 | 2200 | static int ftrace_allocate_records(struct ftrace_page *pg, int count) |
3c1720f0 | 2201 | { |
a7900875 | 2202 | int order; |
3c1720f0 | 2203 | int cnt; |
3c1720f0 | 2204 | |
a7900875 SR |
2205 | if (WARN_ON(!count)) |
2206 | return -EINVAL; | |
2207 | ||
2208 | order = get_count_order(DIV_ROUND_UP(count, ENTRIES_PER_PAGE)); | |
3c1720f0 SR |
2209 | |
2210 | /* | |
a7900875 SR |
2211 | * We want to fill as much as possible. No more than a page |
2212 | * may be empty. | |
3c1720f0 | 2213 | */ |
a7900875 SR |
2214 | while ((PAGE_SIZE << order) / ENTRY_SIZE >= count + ENTRIES_PER_PAGE) |
2215 | order--; | |
3c1720f0 | 2216 | |
a7900875 SR |
2217 | again: |
2218 | pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); | |
3c1720f0 | 2219 | |
a7900875 SR |
2220 | if (!pg->records) { |
2221 | /* if we can't allocate this size, try something smaller */ | |
2222 | if (!order) | |
2223 | return -ENOMEM; | |
2224 | order >>= 1; | |
2225 | goto again; | |
2226 | } | |
3c1720f0 | 2227 | |
a7900875 SR |
2228 | cnt = (PAGE_SIZE << order) / ENTRY_SIZE; |
2229 | pg->size = cnt; | |
3c1720f0 | 2230 | |
a7900875 SR |
2231 | if (cnt > count) |
2232 | cnt = count; | |
2233 | ||
2234 | return cnt; | |
2235 | } | |
2236 | ||
2237 | static struct ftrace_page * | |
2238 | ftrace_allocate_pages(unsigned long num_to_init) | |
2239 | { | |
2240 | struct ftrace_page *start_pg; | |
2241 | struct ftrace_page *pg; | |
2242 | int order; | |
2243 | int cnt; | |
2244 | ||
2245 | if (!num_to_init) | |
2246 | return 0; | |
2247 | ||
2248 | start_pg = pg = kzalloc(sizeof(*pg), GFP_KERNEL); | |
2249 | if (!pg) | |
2250 | return NULL; | |
2251 | ||
2252 | /* | |
2253 | * Try to allocate as much as possible in one continues | |
2254 | * location that fills in all of the space. We want to | |
2255 | * waste as little space as possible. | |
2256 | */ | |
2257 | for (;;) { | |
2258 | cnt = ftrace_allocate_records(pg, num_to_init); | |
2259 | if (cnt < 0) | |
2260 | goto free_pages; | |
2261 | ||
2262 | num_to_init -= cnt; | |
2263 | if (!num_to_init) | |
3c1720f0 SR |
2264 | break; |
2265 | ||
a7900875 SR |
2266 | pg->next = kzalloc(sizeof(*pg), GFP_KERNEL); |
2267 | if (!pg->next) | |
2268 | goto free_pages; | |
2269 | ||
3c1720f0 SR |
2270 | pg = pg->next; |
2271 | } | |
2272 | ||
a7900875 SR |
2273 | return start_pg; |
2274 | ||
2275 | free_pages: | |
2276 | while (start_pg) { | |
2277 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); | |
2278 | free_pages((unsigned long)pg->records, order); | |
2279 | start_pg = pg->next; | |
2280 | kfree(pg); | |
2281 | pg = start_pg; | |
2282 | } | |
2283 | pr_info("ftrace: FAILED to allocate memory for functions\n"); | |
2284 | return NULL; | |
2285 | } | |
2286 | ||
2287 | static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) | |
2288 | { | |
2289 | int cnt; | |
2290 | ||
2291 | if (!num_to_init) { | |
2292 | pr_info("ftrace: No functions to be traced?\n"); | |
2293 | return -1; | |
2294 | } | |
2295 | ||
2296 | cnt = num_to_init / ENTRIES_PER_PAGE; | |
2297 | pr_info("ftrace: allocating %ld entries in %d pages\n", | |
2298 | num_to_init, cnt + 1); | |
2299 | ||
3c1720f0 SR |
2300 | return 0; |
2301 | } | |
2302 | ||
5072c59f SR |
2303 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ |
2304 | ||
2305 | struct ftrace_iterator { | |
98c4fd04 | 2306 | loff_t pos; |
4aeb6967 SR |
2307 | loff_t func_pos; |
2308 | struct ftrace_page *pg; | |
2309 | struct dyn_ftrace *func; | |
2310 | struct ftrace_func_probe *probe; | |
2311 | struct trace_parser parser; | |
1cf41dd7 | 2312 | struct ftrace_hash *hash; |
33dc9b12 | 2313 | struct ftrace_ops *ops; |
4aeb6967 SR |
2314 | int hidx; |
2315 | int idx; | |
2316 | unsigned flags; | |
5072c59f SR |
2317 | }; |
2318 | ||
8fc0c701 | 2319 | static void * |
4aeb6967 | 2320 | t_hash_next(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
2321 | { |
2322 | struct ftrace_iterator *iter = m->private; | |
4aeb6967 | 2323 | struct hlist_node *hnd = NULL; |
8fc0c701 SR |
2324 | struct hlist_head *hhd; |
2325 | ||
8fc0c701 | 2326 | (*pos)++; |
98c4fd04 | 2327 | iter->pos = *pos; |
8fc0c701 | 2328 | |
4aeb6967 SR |
2329 | if (iter->probe) |
2330 | hnd = &iter->probe->node; | |
8fc0c701 SR |
2331 | retry: |
2332 | if (iter->hidx >= FTRACE_FUNC_HASHSIZE) | |
2333 | return NULL; | |
2334 | ||
2335 | hhd = &ftrace_func_hash[iter->hidx]; | |
2336 | ||
2337 | if (hlist_empty(hhd)) { | |
2338 | iter->hidx++; | |
2339 | hnd = NULL; | |
2340 | goto retry; | |
2341 | } | |
2342 | ||
2343 | if (!hnd) | |
2344 | hnd = hhd->first; | |
2345 | else { | |
2346 | hnd = hnd->next; | |
2347 | if (!hnd) { | |
2348 | iter->hidx++; | |
2349 | goto retry; | |
2350 | } | |
2351 | } | |
2352 | ||
4aeb6967 SR |
2353 | if (WARN_ON_ONCE(!hnd)) |
2354 | return NULL; | |
2355 | ||
2356 | iter->probe = hlist_entry(hnd, struct ftrace_func_probe, node); | |
2357 | ||
2358 | return iter; | |
8fc0c701 SR |
2359 | } |
2360 | ||
2361 | static void *t_hash_start(struct seq_file *m, loff_t *pos) | |
2362 | { | |
2363 | struct ftrace_iterator *iter = m->private; | |
2364 | void *p = NULL; | |
d82d6244 LZ |
2365 | loff_t l; |
2366 | ||
69a3083c SR |
2367 | if (!(iter->flags & FTRACE_ITER_DO_HASH)) |
2368 | return NULL; | |
2369 | ||
2bccfffd SR |
2370 | if (iter->func_pos > *pos) |
2371 | return NULL; | |
8fc0c701 | 2372 | |
d82d6244 | 2373 | iter->hidx = 0; |
2bccfffd | 2374 | for (l = 0; l <= (*pos - iter->func_pos); ) { |
4aeb6967 | 2375 | p = t_hash_next(m, &l); |
d82d6244 LZ |
2376 | if (!p) |
2377 | break; | |
2378 | } | |
4aeb6967 SR |
2379 | if (!p) |
2380 | return NULL; | |
2381 | ||
98c4fd04 SR |
2382 | /* Only set this if we have an item */ |
2383 | iter->flags |= FTRACE_ITER_HASH; | |
2384 | ||
4aeb6967 | 2385 | return iter; |
8fc0c701 SR |
2386 | } |
2387 | ||
4aeb6967 SR |
2388 | static int |
2389 | t_hash_show(struct seq_file *m, struct ftrace_iterator *iter) | |
8fc0c701 | 2390 | { |
b6887d79 | 2391 | struct ftrace_func_probe *rec; |
8fc0c701 | 2392 | |
4aeb6967 SR |
2393 | rec = iter->probe; |
2394 | if (WARN_ON_ONCE(!rec)) | |
2395 | return -EIO; | |
8fc0c701 | 2396 | |
809dcf29 SR |
2397 | if (rec->ops->print) |
2398 | return rec->ops->print(m, rec->ip, rec->ops, rec->data); | |
2399 | ||
b375a11a | 2400 | seq_printf(m, "%ps:%ps", (void *)rec->ip, (void *)rec->ops->func); |
8fc0c701 SR |
2401 | |
2402 | if (rec->data) | |
2403 | seq_printf(m, ":%p", rec->data); | |
2404 | seq_putc(m, '\n'); | |
2405 | ||
2406 | return 0; | |
2407 | } | |
2408 | ||
e309b41d | 2409 | static void * |
5072c59f SR |
2410 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2411 | { | |
2412 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 2413 | struct ftrace_ops *ops = iter->ops; |
5072c59f SR |
2414 | struct dyn_ftrace *rec = NULL; |
2415 | ||
45a4a237 SR |
2416 | if (unlikely(ftrace_disabled)) |
2417 | return NULL; | |
2418 | ||
8fc0c701 | 2419 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 2420 | return t_hash_next(m, pos); |
8fc0c701 | 2421 | |
5072c59f | 2422 | (*pos)++; |
1106b699 | 2423 | iter->pos = iter->func_pos = *pos; |
5072c59f | 2424 | |
0c75a3ed | 2425 | if (iter->flags & FTRACE_ITER_PRINTALL) |
57c072c7 | 2426 | return t_hash_start(m, pos); |
0c75a3ed | 2427 | |
5072c59f SR |
2428 | retry: |
2429 | if (iter->idx >= iter->pg->index) { | |
2430 | if (iter->pg->next) { | |
2431 | iter->pg = iter->pg->next; | |
2432 | iter->idx = 0; | |
2433 | goto retry; | |
2434 | } | |
2435 | } else { | |
2436 | rec = &iter->pg->records[iter->idx++]; | |
32082309 | 2437 | if (((iter->flags & FTRACE_ITER_FILTER) && |
f45948e8 | 2438 | !(ftrace_lookup_ip(ops->filter_hash, rec->ip))) || |
0183fb1c | 2439 | |
41c52c0d | 2440 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
647bcd03 SR |
2441 | !ftrace_lookup_ip(ops->notrace_hash, rec->ip)) || |
2442 | ||
2443 | ((iter->flags & FTRACE_ITER_ENABLED) && | |
2444 | !(rec->flags & ~FTRACE_FL_MASK))) { | |
2445 | ||
5072c59f SR |
2446 | rec = NULL; |
2447 | goto retry; | |
2448 | } | |
2449 | } | |
2450 | ||
4aeb6967 | 2451 | if (!rec) |
57c072c7 | 2452 | return t_hash_start(m, pos); |
4aeb6967 SR |
2453 | |
2454 | iter->func = rec; | |
2455 | ||
2456 | return iter; | |
5072c59f SR |
2457 | } |
2458 | ||
98c4fd04 SR |
2459 | static void reset_iter_read(struct ftrace_iterator *iter) |
2460 | { | |
2461 | iter->pos = 0; | |
2462 | iter->func_pos = 0; | |
70f77b3f | 2463 | iter->flags &= ~(FTRACE_ITER_PRINTALL | FTRACE_ITER_HASH); |
5072c59f SR |
2464 | } |
2465 | ||
2466 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2467 | { | |
2468 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 2469 | struct ftrace_ops *ops = iter->ops; |
5072c59f | 2470 | void *p = NULL; |
694ce0a5 | 2471 | loff_t l; |
5072c59f | 2472 | |
8fc0c701 | 2473 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
2474 | |
2475 | if (unlikely(ftrace_disabled)) | |
2476 | return NULL; | |
2477 | ||
98c4fd04 SR |
2478 | /* |
2479 | * If an lseek was done, then reset and start from beginning. | |
2480 | */ | |
2481 | if (*pos < iter->pos) | |
2482 | reset_iter_read(iter); | |
2483 | ||
0c75a3ed SR |
2484 | /* |
2485 | * For set_ftrace_filter reading, if we have the filter | |
2486 | * off, we can short cut and just print out that all | |
2487 | * functions are enabled. | |
2488 | */ | |
06a51d93 SR |
2489 | if (iter->flags & FTRACE_ITER_FILTER && |
2490 | ftrace_hash_empty(ops->filter_hash)) { | |
0c75a3ed | 2491 | if (*pos > 0) |
8fc0c701 | 2492 | return t_hash_start(m, pos); |
0c75a3ed | 2493 | iter->flags |= FTRACE_ITER_PRINTALL; |
df091625 CW |
2494 | /* reset in case of seek/pread */ |
2495 | iter->flags &= ~FTRACE_ITER_HASH; | |
0c75a3ed SR |
2496 | return iter; |
2497 | } | |
2498 | ||
8fc0c701 SR |
2499 | if (iter->flags & FTRACE_ITER_HASH) |
2500 | return t_hash_start(m, pos); | |
2501 | ||
98c4fd04 SR |
2502 | /* |
2503 | * Unfortunately, we need to restart at ftrace_pages_start | |
2504 | * every time we let go of the ftrace_mutex. This is because | |
2505 | * those pointers can change without the lock. | |
2506 | */ | |
694ce0a5 LZ |
2507 | iter->pg = ftrace_pages_start; |
2508 | iter->idx = 0; | |
2509 | for (l = 0; l <= *pos; ) { | |
2510 | p = t_next(m, p, &l); | |
2511 | if (!p) | |
2512 | break; | |
50cdaf08 | 2513 | } |
5821e1b7 | 2514 | |
69a3083c SR |
2515 | if (!p) |
2516 | return t_hash_start(m, pos); | |
4aeb6967 SR |
2517 | |
2518 | return iter; | |
5072c59f SR |
2519 | } |
2520 | ||
2521 | static void t_stop(struct seq_file *m, void *p) | |
2522 | { | |
8fc0c701 | 2523 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
2524 | } |
2525 | ||
2526 | static int t_show(struct seq_file *m, void *v) | |
2527 | { | |
0c75a3ed | 2528 | struct ftrace_iterator *iter = m->private; |
4aeb6967 | 2529 | struct dyn_ftrace *rec; |
5072c59f | 2530 | |
8fc0c701 | 2531 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 2532 | return t_hash_show(m, iter); |
8fc0c701 | 2533 | |
0c75a3ed SR |
2534 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
2535 | seq_printf(m, "#### all functions enabled ####\n"); | |
2536 | return 0; | |
2537 | } | |
2538 | ||
4aeb6967 SR |
2539 | rec = iter->func; |
2540 | ||
5072c59f SR |
2541 | if (!rec) |
2542 | return 0; | |
2543 | ||
647bcd03 SR |
2544 | seq_printf(m, "%ps", (void *)rec->ip); |
2545 | if (iter->flags & FTRACE_ITER_ENABLED) | |
08f6fba5 SR |
2546 | seq_printf(m, " (%ld)%s", |
2547 | rec->flags & ~FTRACE_FL_MASK, | |
2548 | rec->flags & FTRACE_FL_REGS ? " R" : ""); | |
647bcd03 | 2549 | seq_printf(m, "\n"); |
5072c59f SR |
2550 | |
2551 | return 0; | |
2552 | } | |
2553 | ||
88e9d34c | 2554 | static const struct seq_operations show_ftrace_seq_ops = { |
5072c59f SR |
2555 | .start = t_start, |
2556 | .next = t_next, | |
2557 | .stop = t_stop, | |
2558 | .show = t_show, | |
2559 | }; | |
2560 | ||
e309b41d | 2561 | static int |
5072c59f SR |
2562 | ftrace_avail_open(struct inode *inode, struct file *file) |
2563 | { | |
2564 | struct ftrace_iterator *iter; | |
5072c59f | 2565 | |
4eebcc81 SR |
2566 | if (unlikely(ftrace_disabled)) |
2567 | return -ENODEV; | |
2568 | ||
50e18b94 JO |
2569 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
2570 | if (iter) { | |
2571 | iter->pg = ftrace_pages_start; | |
2572 | iter->ops = &global_ops; | |
4bf39a94 | 2573 | } |
5072c59f | 2574 | |
50e18b94 | 2575 | return iter ? 0 : -ENOMEM; |
5072c59f SR |
2576 | } |
2577 | ||
647bcd03 SR |
2578 | static int |
2579 | ftrace_enabled_open(struct inode *inode, struct file *file) | |
2580 | { | |
2581 | struct ftrace_iterator *iter; | |
647bcd03 SR |
2582 | |
2583 | if (unlikely(ftrace_disabled)) | |
2584 | return -ENODEV; | |
2585 | ||
50e18b94 JO |
2586 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
2587 | if (iter) { | |
2588 | iter->pg = ftrace_pages_start; | |
2589 | iter->flags = FTRACE_ITER_ENABLED; | |
2590 | iter->ops = &global_ops; | |
647bcd03 SR |
2591 | } |
2592 | ||
50e18b94 | 2593 | return iter ? 0 : -ENOMEM; |
647bcd03 SR |
2594 | } |
2595 | ||
1cf41dd7 | 2596 | static void ftrace_filter_reset(struct ftrace_hash *hash) |
5072c59f | 2597 | { |
52baf119 | 2598 | mutex_lock(&ftrace_lock); |
1cf41dd7 | 2599 | ftrace_hash_clear(hash); |
52baf119 | 2600 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
2601 | } |
2602 | ||
fc13cb0c SR |
2603 | /** |
2604 | * ftrace_regex_open - initialize function tracer filter files | |
2605 | * @ops: The ftrace_ops that hold the hash filters | |
2606 | * @flag: The type of filter to process | |
2607 | * @inode: The inode, usually passed in to your open routine | |
2608 | * @file: The file, usually passed in to your open routine | |
2609 | * | |
2610 | * ftrace_regex_open() initializes the filter files for the | |
2611 | * @ops. Depending on @flag it may process the filter hash or | |
2612 | * the notrace hash of @ops. With this called from the open | |
2613 | * routine, you can use ftrace_filter_write() for the write | |
2614 | * routine if @flag has FTRACE_ITER_FILTER set, or | |
2615 | * ftrace_notrace_write() if @flag has FTRACE_ITER_NOTRACE set. | |
2616 | * ftrace_regex_lseek() should be used as the lseek routine, and | |
2617 | * release must call ftrace_regex_release(). | |
2618 | */ | |
2619 | int | |
f45948e8 | 2620 | ftrace_regex_open(struct ftrace_ops *ops, int flag, |
1cf41dd7 | 2621 | struct inode *inode, struct file *file) |
5072c59f SR |
2622 | { |
2623 | struct ftrace_iterator *iter; | |
f45948e8 | 2624 | struct ftrace_hash *hash; |
5072c59f SR |
2625 | int ret = 0; |
2626 | ||
4eebcc81 SR |
2627 | if (unlikely(ftrace_disabled)) |
2628 | return -ENODEV; | |
2629 | ||
5072c59f SR |
2630 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
2631 | if (!iter) | |
2632 | return -ENOMEM; | |
2633 | ||
689fd8b6 | 2634 | if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) { |
2635 | kfree(iter); | |
2636 | return -ENOMEM; | |
2637 | } | |
2638 | ||
f45948e8 SR |
2639 | if (flag & FTRACE_ITER_NOTRACE) |
2640 | hash = ops->notrace_hash; | |
2641 | else | |
2642 | hash = ops->filter_hash; | |
2643 | ||
33dc9b12 SR |
2644 | iter->ops = ops; |
2645 | iter->flags = flag; | |
2646 | ||
2647 | if (file->f_mode & FMODE_WRITE) { | |
2648 | mutex_lock(&ftrace_lock); | |
2649 | iter->hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash); | |
2650 | mutex_unlock(&ftrace_lock); | |
2651 | ||
2652 | if (!iter->hash) { | |
2653 | trace_parser_put(&iter->parser); | |
2654 | kfree(iter); | |
2655 | return -ENOMEM; | |
2656 | } | |
2657 | } | |
1cf41dd7 | 2658 | |
41c52c0d | 2659 | mutex_lock(&ftrace_regex_lock); |
33dc9b12 | 2660 | |
5072c59f | 2661 | if ((file->f_mode & FMODE_WRITE) && |
8650ae32 | 2662 | (file->f_flags & O_TRUNC)) |
33dc9b12 | 2663 | ftrace_filter_reset(iter->hash); |
5072c59f SR |
2664 | |
2665 | if (file->f_mode & FMODE_READ) { | |
2666 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
2667 | |
2668 | ret = seq_open(file, &show_ftrace_seq_ops); | |
2669 | if (!ret) { | |
2670 | struct seq_file *m = file->private_data; | |
2671 | m->private = iter; | |
79fe249c | 2672 | } else { |
33dc9b12 SR |
2673 | /* Failed */ |
2674 | free_ftrace_hash(iter->hash); | |
79fe249c | 2675 | trace_parser_put(&iter->parser); |
5072c59f | 2676 | kfree(iter); |
79fe249c | 2677 | } |
5072c59f SR |
2678 | } else |
2679 | file->private_data = iter; | |
41c52c0d | 2680 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
2681 | |
2682 | return ret; | |
2683 | } | |
2684 | ||
41c52c0d SR |
2685 | static int |
2686 | ftrace_filter_open(struct inode *inode, struct file *file) | |
2687 | { | |
69a3083c SR |
2688 | return ftrace_regex_open(&global_ops, |
2689 | FTRACE_ITER_FILTER | FTRACE_ITER_DO_HASH, | |
2690 | inode, file); | |
41c52c0d SR |
2691 | } |
2692 | ||
2693 | static int | |
2694 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
2695 | { | |
f45948e8 | 2696 | return ftrace_regex_open(&global_ops, FTRACE_ITER_NOTRACE, |
1cf41dd7 | 2697 | inode, file); |
41c52c0d SR |
2698 | } |
2699 | ||
fc13cb0c | 2700 | loff_t |
965c8e59 | 2701 | ftrace_regex_lseek(struct file *file, loff_t offset, int whence) |
5072c59f SR |
2702 | { |
2703 | loff_t ret; | |
2704 | ||
2705 | if (file->f_mode & FMODE_READ) | |
965c8e59 | 2706 | ret = seq_lseek(file, offset, whence); |
5072c59f SR |
2707 | else |
2708 | file->f_pos = ret = 1; | |
2709 | ||
2710 | return ret; | |
2711 | } | |
2712 | ||
64e7c440 | 2713 | static int ftrace_match(char *str, char *regex, int len, int type) |
9f4801e3 | 2714 | { |
9f4801e3 | 2715 | int matched = 0; |
751e9983 | 2716 | int slen; |
9f4801e3 | 2717 | |
9f4801e3 SR |
2718 | switch (type) { |
2719 | case MATCH_FULL: | |
2720 | if (strcmp(str, regex) == 0) | |
2721 | matched = 1; | |
2722 | break; | |
2723 | case MATCH_FRONT_ONLY: | |
2724 | if (strncmp(str, regex, len) == 0) | |
2725 | matched = 1; | |
2726 | break; | |
2727 | case MATCH_MIDDLE_ONLY: | |
2728 | if (strstr(str, regex)) | |
2729 | matched = 1; | |
2730 | break; | |
2731 | case MATCH_END_ONLY: | |
751e9983 LZ |
2732 | slen = strlen(str); |
2733 | if (slen >= len && memcmp(str + slen - len, regex, len) == 0) | |
9f4801e3 SR |
2734 | matched = 1; |
2735 | break; | |
2736 | } | |
2737 | ||
2738 | return matched; | |
2739 | } | |
2740 | ||
b448c4e3 | 2741 | static int |
1cf41dd7 | 2742 | enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int not) |
996e87be | 2743 | { |
b448c4e3 | 2744 | struct ftrace_func_entry *entry; |
b448c4e3 SR |
2745 | int ret = 0; |
2746 | ||
1cf41dd7 SR |
2747 | entry = ftrace_lookup_ip(hash, rec->ip); |
2748 | if (not) { | |
2749 | /* Do nothing if it doesn't exist */ | |
2750 | if (!entry) | |
2751 | return 0; | |
b448c4e3 | 2752 | |
33dc9b12 | 2753 | free_hash_entry(hash, entry); |
1cf41dd7 SR |
2754 | } else { |
2755 | /* Do nothing if it exists */ | |
2756 | if (entry) | |
2757 | return 0; | |
b448c4e3 | 2758 | |
1cf41dd7 | 2759 | ret = add_hash_entry(hash, rec->ip); |
b448c4e3 SR |
2760 | } |
2761 | return ret; | |
996e87be SR |
2762 | } |
2763 | ||
64e7c440 | 2764 | static int |
b9df92d2 SR |
2765 | ftrace_match_record(struct dyn_ftrace *rec, char *mod, |
2766 | char *regex, int len, int type) | |
64e7c440 SR |
2767 | { |
2768 | char str[KSYM_SYMBOL_LEN]; | |
b9df92d2 SR |
2769 | char *modname; |
2770 | ||
2771 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); | |
2772 | ||
2773 | if (mod) { | |
2774 | /* module lookup requires matching the module */ | |
2775 | if (!modname || strcmp(modname, mod)) | |
2776 | return 0; | |
2777 | ||
2778 | /* blank search means to match all funcs in the mod */ | |
2779 | if (!len) | |
2780 | return 1; | |
2781 | } | |
64e7c440 | 2782 | |
64e7c440 SR |
2783 | return ftrace_match(str, regex, len, type); |
2784 | } | |
2785 | ||
1cf41dd7 SR |
2786 | static int |
2787 | match_records(struct ftrace_hash *hash, char *buff, | |
2788 | int len, char *mod, int not) | |
9f4801e3 | 2789 | { |
b9df92d2 | 2790 | unsigned search_len = 0; |
9f4801e3 SR |
2791 | struct ftrace_page *pg; |
2792 | struct dyn_ftrace *rec; | |
b9df92d2 SR |
2793 | int type = MATCH_FULL; |
2794 | char *search = buff; | |
311d16da | 2795 | int found = 0; |
b448c4e3 | 2796 | int ret; |
9f4801e3 | 2797 | |
b9df92d2 SR |
2798 | if (len) { |
2799 | type = filter_parse_regex(buff, len, &search, ¬); | |
2800 | search_len = strlen(search); | |
2801 | } | |
9f4801e3 | 2802 | |
52baf119 | 2803 | mutex_lock(&ftrace_lock); |
265c831c | 2804 | |
b9df92d2 SR |
2805 | if (unlikely(ftrace_disabled)) |
2806 | goto out_unlock; | |
9f4801e3 | 2807 | |
265c831c | 2808 | do_for_each_ftrace_rec(pg, rec) { |
b9df92d2 | 2809 | if (ftrace_match_record(rec, mod, search, search_len, type)) { |
1cf41dd7 | 2810 | ret = enter_record(hash, rec, not); |
b448c4e3 SR |
2811 | if (ret < 0) { |
2812 | found = ret; | |
2813 | goto out_unlock; | |
2814 | } | |
311d16da | 2815 | found = 1; |
265c831c SR |
2816 | } |
2817 | } while_for_each_ftrace_rec(); | |
b9df92d2 | 2818 | out_unlock: |
52baf119 | 2819 | mutex_unlock(&ftrace_lock); |
311d16da LZ |
2820 | |
2821 | return found; | |
5072c59f SR |
2822 | } |
2823 | ||
64e7c440 | 2824 | static int |
1cf41dd7 | 2825 | ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) |
64e7c440 | 2826 | { |
1cf41dd7 | 2827 | return match_records(hash, buff, len, NULL, 0); |
64e7c440 SR |
2828 | } |
2829 | ||
1cf41dd7 SR |
2830 | static int |
2831 | ftrace_match_module_records(struct ftrace_hash *hash, char *buff, char *mod) | |
64e7c440 | 2832 | { |
64e7c440 | 2833 | int not = 0; |
6a24a244 | 2834 | |
64e7c440 SR |
2835 | /* blank or '*' mean the same */ |
2836 | if (strcmp(buff, "*") == 0) | |
2837 | buff[0] = 0; | |
2838 | ||
2839 | /* handle the case of 'dont filter this module' */ | |
2840 | if (strcmp(buff, "!") == 0 || strcmp(buff, "!*") == 0) { | |
2841 | buff[0] = 0; | |
2842 | not = 1; | |
2843 | } | |
2844 | ||
1cf41dd7 | 2845 | return match_records(hash, buff, strlen(buff), mod, not); |
64e7c440 SR |
2846 | } |
2847 | ||
f6180773 SR |
2848 | /* |
2849 | * We register the module command as a template to show others how | |
2850 | * to register the a command as well. | |
2851 | */ | |
2852 | ||
2853 | static int | |
43dd61c9 SR |
2854 | ftrace_mod_callback(struct ftrace_hash *hash, |
2855 | char *func, char *cmd, char *param, int enable) | |
f6180773 SR |
2856 | { |
2857 | char *mod; | |
b448c4e3 | 2858 | int ret = -EINVAL; |
f6180773 SR |
2859 | |
2860 | /* | |
2861 | * cmd == 'mod' because we only registered this func | |
2862 | * for the 'mod' ftrace_func_command. | |
2863 | * But if you register one func with multiple commands, | |
2864 | * you can tell which command was used by the cmd | |
2865 | * parameter. | |
2866 | */ | |
2867 | ||
2868 | /* we must have a module name */ | |
2869 | if (!param) | |
b448c4e3 | 2870 | return ret; |
f6180773 SR |
2871 | |
2872 | mod = strsep(¶m, ":"); | |
2873 | if (!strlen(mod)) | |
b448c4e3 | 2874 | return ret; |
f6180773 | 2875 | |
1cf41dd7 | 2876 | ret = ftrace_match_module_records(hash, func, mod); |
b448c4e3 SR |
2877 | if (!ret) |
2878 | ret = -EINVAL; | |
2879 | if (ret < 0) | |
2880 | return ret; | |
2881 | ||
2882 | return 0; | |
f6180773 SR |
2883 | } |
2884 | ||
2885 | static struct ftrace_func_command ftrace_mod_cmd = { | |
2886 | .name = "mod", | |
2887 | .func = ftrace_mod_callback, | |
2888 | }; | |
2889 | ||
2890 | static int __init ftrace_mod_cmd_init(void) | |
2891 | { | |
2892 | return register_ftrace_command(&ftrace_mod_cmd); | |
2893 | } | |
6f415672 | 2894 | core_initcall(ftrace_mod_cmd_init); |
f6180773 | 2895 | |
2f5f6ad9 | 2896 | static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 2897 | struct ftrace_ops *op, struct pt_regs *pt_regs) |
59df055f | 2898 | { |
b6887d79 | 2899 | struct ftrace_func_probe *entry; |
59df055f | 2900 | struct hlist_head *hhd; |
59df055f | 2901 | unsigned long key; |
59df055f SR |
2902 | |
2903 | key = hash_long(ip, FTRACE_HASH_BITS); | |
2904 | ||
2905 | hhd = &ftrace_func_hash[key]; | |
2906 | ||
2907 | if (hlist_empty(hhd)) | |
2908 | return; | |
2909 | ||
2910 | /* | |
2911 | * Disable preemption for these calls to prevent a RCU grace | |
2912 | * period. This syncs the hash iteration and freeing of items | |
2913 | * on the hash. rcu_read_lock is too dangerous here. | |
2914 | */ | |
5168ae50 | 2915 | preempt_disable_notrace(); |
b67bfe0d | 2916 | hlist_for_each_entry_rcu(entry, hhd, node) { |
59df055f SR |
2917 | if (entry->ip == ip) |
2918 | entry->ops->func(ip, parent_ip, &entry->data); | |
2919 | } | |
5168ae50 | 2920 | preempt_enable_notrace(); |
59df055f SR |
2921 | } |
2922 | ||
b6887d79 | 2923 | static struct ftrace_ops trace_probe_ops __read_mostly = |
59df055f | 2924 | { |
fb9fb015 | 2925 | .func = function_trace_probe_call, |
59df055f SR |
2926 | }; |
2927 | ||
b6887d79 | 2928 | static int ftrace_probe_registered; |
59df055f | 2929 | |
b6887d79 | 2930 | static void __enable_ftrace_function_probe(void) |
59df055f | 2931 | { |
b848914c | 2932 | int ret; |
59df055f SR |
2933 | int i; |
2934 | ||
b6887d79 | 2935 | if (ftrace_probe_registered) |
59df055f SR |
2936 | return; |
2937 | ||
2938 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
2939 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
2940 | if (hhd->first) | |
2941 | break; | |
2942 | } | |
2943 | /* Nothing registered? */ | |
2944 | if (i == FTRACE_FUNC_HASHSIZE) | |
2945 | return; | |
2946 | ||
b848914c SR |
2947 | ret = __register_ftrace_function(&trace_probe_ops); |
2948 | if (!ret) | |
a1cd6173 | 2949 | ret = ftrace_startup(&trace_probe_ops, 0); |
b848914c | 2950 | |
b6887d79 | 2951 | ftrace_probe_registered = 1; |
59df055f SR |
2952 | } |
2953 | ||
b6887d79 | 2954 | static void __disable_ftrace_function_probe(void) |
59df055f | 2955 | { |
b848914c | 2956 | int ret; |
59df055f SR |
2957 | int i; |
2958 | ||
b6887d79 | 2959 | if (!ftrace_probe_registered) |
59df055f SR |
2960 | return; |
2961 | ||
2962 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
2963 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
2964 | if (hhd->first) | |
2965 | return; | |
2966 | } | |
2967 | ||
2968 | /* no more funcs left */ | |
b848914c SR |
2969 | ret = __unregister_ftrace_function(&trace_probe_ops); |
2970 | if (!ret) | |
2971 | ftrace_shutdown(&trace_probe_ops, 0); | |
2972 | ||
b6887d79 | 2973 | ftrace_probe_registered = 0; |
59df055f SR |
2974 | } |
2975 | ||
2976 | ||
2977 | static void ftrace_free_entry_rcu(struct rcu_head *rhp) | |
2978 | { | |
b6887d79 SR |
2979 | struct ftrace_func_probe *entry = |
2980 | container_of(rhp, struct ftrace_func_probe, rcu); | |
59df055f SR |
2981 | |
2982 | if (entry->ops->free) | |
2983 | entry->ops->free(&entry->data); | |
2984 | kfree(entry); | |
2985 | } | |
2986 | ||
2987 | ||
2988 | int | |
b6887d79 | 2989 | register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
2990 | void *data) |
2991 | { | |
b6887d79 | 2992 | struct ftrace_func_probe *entry; |
59df055f SR |
2993 | struct ftrace_page *pg; |
2994 | struct dyn_ftrace *rec; | |
59df055f | 2995 | int type, len, not; |
6a24a244 | 2996 | unsigned long key; |
59df055f SR |
2997 | int count = 0; |
2998 | char *search; | |
2999 | ||
3f6fe06d | 3000 | type = filter_parse_regex(glob, strlen(glob), &search, ¬); |
59df055f SR |
3001 | len = strlen(search); |
3002 | ||
b6887d79 | 3003 | /* we do not support '!' for function probes */ |
59df055f SR |
3004 | if (WARN_ON(not)) |
3005 | return -EINVAL; | |
3006 | ||
3007 | mutex_lock(&ftrace_lock); | |
59df055f | 3008 | |
45a4a237 SR |
3009 | if (unlikely(ftrace_disabled)) |
3010 | goto out_unlock; | |
59df055f | 3011 | |
45a4a237 | 3012 | do_for_each_ftrace_rec(pg, rec) { |
59df055f | 3013 | |
b9df92d2 | 3014 | if (!ftrace_match_record(rec, NULL, search, len, type)) |
59df055f SR |
3015 | continue; |
3016 | ||
3017 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
3018 | if (!entry) { | |
b6887d79 | 3019 | /* If we did not process any, then return error */ |
59df055f SR |
3020 | if (!count) |
3021 | count = -ENOMEM; | |
3022 | goto out_unlock; | |
3023 | } | |
3024 | ||
3025 | count++; | |
3026 | ||
3027 | entry->data = data; | |
3028 | ||
3029 | /* | |
3030 | * The caller might want to do something special | |
3031 | * for each function we find. We call the callback | |
3032 | * to give the caller an opportunity to do so. | |
3033 | */ | |
3034 | if (ops->callback) { | |
3035 | if (ops->callback(rec->ip, &entry->data) < 0) { | |
3036 | /* caller does not like this func */ | |
3037 | kfree(entry); | |
3038 | continue; | |
3039 | } | |
3040 | } | |
3041 | ||
3042 | entry->ops = ops; | |
3043 | entry->ip = rec->ip; | |
3044 | ||
3045 | key = hash_long(entry->ip, FTRACE_HASH_BITS); | |
3046 | hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]); | |
3047 | ||
3048 | } while_for_each_ftrace_rec(); | |
b6887d79 | 3049 | __enable_ftrace_function_probe(); |
59df055f SR |
3050 | |
3051 | out_unlock: | |
3052 | mutex_unlock(&ftrace_lock); | |
3053 | ||
3054 | return count; | |
3055 | } | |
3056 | ||
3057 | enum { | |
b6887d79 SR |
3058 | PROBE_TEST_FUNC = 1, |
3059 | PROBE_TEST_DATA = 2 | |
59df055f SR |
3060 | }; |
3061 | ||
3062 | static void | |
b6887d79 | 3063 | __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3064 | void *data, int flags) |
3065 | { | |
b6887d79 | 3066 | struct ftrace_func_probe *entry; |
b67bfe0d | 3067 | struct hlist_node *tmp; |
59df055f SR |
3068 | char str[KSYM_SYMBOL_LEN]; |
3069 | int type = MATCH_FULL; | |
3070 | int i, len = 0; | |
3071 | char *search; | |
3072 | ||
b36461da | 3073 | if (glob && (strcmp(glob, "*") == 0 || !strlen(glob))) |
59df055f | 3074 | glob = NULL; |
b36461da | 3075 | else if (glob) { |
59df055f SR |
3076 | int not; |
3077 | ||
3f6fe06d | 3078 | type = filter_parse_regex(glob, strlen(glob), &search, ¬); |
59df055f SR |
3079 | len = strlen(search); |
3080 | ||
b6887d79 | 3081 | /* we do not support '!' for function probes */ |
59df055f SR |
3082 | if (WARN_ON(not)) |
3083 | return; | |
3084 | } | |
3085 | ||
3086 | mutex_lock(&ftrace_lock); | |
3087 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
3088 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3089 | ||
b67bfe0d | 3090 | hlist_for_each_entry_safe(entry, tmp, hhd, node) { |
59df055f SR |
3091 | |
3092 | /* break up if statements for readability */ | |
b6887d79 | 3093 | if ((flags & PROBE_TEST_FUNC) && entry->ops != ops) |
59df055f SR |
3094 | continue; |
3095 | ||
b6887d79 | 3096 | if ((flags & PROBE_TEST_DATA) && entry->data != data) |
59df055f SR |
3097 | continue; |
3098 | ||
3099 | /* do this last, since it is the most expensive */ | |
3100 | if (glob) { | |
3101 | kallsyms_lookup(entry->ip, NULL, NULL, | |
3102 | NULL, str); | |
3103 | if (!ftrace_match(str, glob, len, type)) | |
3104 | continue; | |
3105 | } | |
3106 | ||
740466bc SRRH |
3107 | hlist_del_rcu(&entry->node); |
3108 | call_rcu_sched(&entry->rcu, ftrace_free_entry_rcu); | |
59df055f SR |
3109 | } |
3110 | } | |
b6887d79 | 3111 | __disable_ftrace_function_probe(); |
59df055f SR |
3112 | mutex_unlock(&ftrace_lock); |
3113 | } | |
3114 | ||
3115 | void | |
b6887d79 | 3116 | unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3117 | void *data) |
3118 | { | |
b6887d79 SR |
3119 | __unregister_ftrace_function_probe(glob, ops, data, |
3120 | PROBE_TEST_FUNC | PROBE_TEST_DATA); | |
59df055f SR |
3121 | } |
3122 | ||
3123 | void | |
b6887d79 | 3124 | unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops) |
59df055f | 3125 | { |
b6887d79 | 3126 | __unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC); |
59df055f SR |
3127 | } |
3128 | ||
b6887d79 | 3129 | void unregister_ftrace_function_probe_all(char *glob) |
59df055f | 3130 | { |
b6887d79 | 3131 | __unregister_ftrace_function_probe(glob, NULL, NULL, 0); |
59df055f SR |
3132 | } |
3133 | ||
f6180773 SR |
3134 | static LIST_HEAD(ftrace_commands); |
3135 | static DEFINE_MUTEX(ftrace_cmd_mutex); | |
3136 | ||
3137 | int register_ftrace_command(struct ftrace_func_command *cmd) | |
3138 | { | |
3139 | struct ftrace_func_command *p; | |
3140 | int ret = 0; | |
3141 | ||
3142 | mutex_lock(&ftrace_cmd_mutex); | |
3143 | list_for_each_entry(p, &ftrace_commands, list) { | |
3144 | if (strcmp(cmd->name, p->name) == 0) { | |
3145 | ret = -EBUSY; | |
3146 | goto out_unlock; | |
3147 | } | |
3148 | } | |
3149 | list_add(&cmd->list, &ftrace_commands); | |
3150 | out_unlock: | |
3151 | mutex_unlock(&ftrace_cmd_mutex); | |
3152 | ||
3153 | return ret; | |
3154 | } | |
3155 | ||
3156 | int unregister_ftrace_command(struct ftrace_func_command *cmd) | |
3157 | { | |
3158 | struct ftrace_func_command *p, *n; | |
3159 | int ret = -ENODEV; | |
3160 | ||
3161 | mutex_lock(&ftrace_cmd_mutex); | |
3162 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { | |
3163 | if (strcmp(cmd->name, p->name) == 0) { | |
3164 | ret = 0; | |
3165 | list_del_init(&p->list); | |
3166 | goto out_unlock; | |
3167 | } | |
3168 | } | |
3169 | out_unlock: | |
3170 | mutex_unlock(&ftrace_cmd_mutex); | |
3171 | ||
3172 | return ret; | |
3173 | } | |
3174 | ||
33dc9b12 SR |
3175 | static int ftrace_process_regex(struct ftrace_hash *hash, |
3176 | char *buff, int len, int enable) | |
64e7c440 | 3177 | { |
f6180773 | 3178 | char *func, *command, *next = buff; |
6a24a244 | 3179 | struct ftrace_func_command *p; |
0aff1c0c | 3180 | int ret = -EINVAL; |
64e7c440 SR |
3181 | |
3182 | func = strsep(&next, ":"); | |
3183 | ||
3184 | if (!next) { | |
1cf41dd7 | 3185 | ret = ftrace_match_records(hash, func, len); |
b448c4e3 SR |
3186 | if (!ret) |
3187 | ret = -EINVAL; | |
3188 | if (ret < 0) | |
3189 | return ret; | |
3190 | return 0; | |
64e7c440 SR |
3191 | } |
3192 | ||
f6180773 | 3193 | /* command found */ |
64e7c440 SR |
3194 | |
3195 | command = strsep(&next, ":"); | |
3196 | ||
f6180773 SR |
3197 | mutex_lock(&ftrace_cmd_mutex); |
3198 | list_for_each_entry(p, &ftrace_commands, list) { | |
3199 | if (strcmp(p->name, command) == 0) { | |
43dd61c9 | 3200 | ret = p->func(hash, func, command, next, enable); |
f6180773 SR |
3201 | goto out_unlock; |
3202 | } | |
64e7c440 | 3203 | } |
f6180773 SR |
3204 | out_unlock: |
3205 | mutex_unlock(&ftrace_cmd_mutex); | |
64e7c440 | 3206 | |
f6180773 | 3207 | return ret; |
64e7c440 SR |
3208 | } |
3209 | ||
e309b41d | 3210 | static ssize_t |
41c52c0d SR |
3211 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
3212 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
3213 | { |
3214 | struct ftrace_iterator *iter; | |
689fd8b6 | 3215 | struct trace_parser *parser; |
3216 | ssize_t ret, read; | |
5072c59f | 3217 | |
4ba7978e | 3218 | if (!cnt) |
5072c59f SR |
3219 | return 0; |
3220 | ||
41c52c0d | 3221 | mutex_lock(&ftrace_regex_lock); |
5072c59f | 3222 | |
45a4a237 SR |
3223 | ret = -ENODEV; |
3224 | if (unlikely(ftrace_disabled)) | |
3225 | goto out_unlock; | |
3226 | ||
5072c59f SR |
3227 | if (file->f_mode & FMODE_READ) { |
3228 | struct seq_file *m = file->private_data; | |
3229 | iter = m->private; | |
3230 | } else | |
3231 | iter = file->private_data; | |
3232 | ||
689fd8b6 | 3233 | parser = &iter->parser; |
3234 | read = trace_get_user(parser, ubuf, cnt, ppos); | |
5072c59f | 3235 | |
4ba7978e | 3236 | if (read >= 0 && trace_parser_loaded(parser) && |
689fd8b6 | 3237 | !trace_parser_cont(parser)) { |
33dc9b12 | 3238 | ret = ftrace_process_regex(iter->hash, parser->buffer, |
689fd8b6 | 3239 | parser->idx, enable); |
313254a9 | 3240 | trace_parser_clear(parser); |
5072c59f | 3241 | if (ret) |
ed146b25 | 3242 | goto out_unlock; |
eda1e328 | 3243 | } |
5072c59f | 3244 | |
5072c59f | 3245 | ret = read; |
ed146b25 | 3246 | out_unlock: |
689fd8b6 | 3247 | mutex_unlock(&ftrace_regex_lock); |
ed146b25 | 3248 | |
5072c59f SR |
3249 | return ret; |
3250 | } | |
3251 | ||
fc13cb0c | 3252 | ssize_t |
41c52c0d SR |
3253 | ftrace_filter_write(struct file *file, const char __user *ubuf, |
3254 | size_t cnt, loff_t *ppos) | |
3255 | { | |
3256 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
3257 | } | |
3258 | ||
fc13cb0c | 3259 | ssize_t |
41c52c0d SR |
3260 | ftrace_notrace_write(struct file *file, const char __user *ubuf, |
3261 | size_t cnt, loff_t *ppos) | |
3262 | { | |
3263 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
3264 | } | |
3265 | ||
33dc9b12 | 3266 | static int |
647664ea MH |
3267 | ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) |
3268 | { | |
3269 | struct ftrace_func_entry *entry; | |
3270 | ||
3271 | if (!ftrace_location(ip)) | |
3272 | return -EINVAL; | |
3273 | ||
3274 | if (remove) { | |
3275 | entry = ftrace_lookup_ip(hash, ip); | |
3276 | if (!entry) | |
3277 | return -ENOENT; | |
3278 | free_hash_entry(hash, entry); | |
3279 | return 0; | |
3280 | } | |
3281 | ||
3282 | return add_hash_entry(hash, ip); | |
3283 | } | |
3284 | ||
3285 | static int | |
3286 | ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, | |
3287 | unsigned long ip, int remove, int reset, int enable) | |
41c52c0d | 3288 | { |
33dc9b12 | 3289 | struct ftrace_hash **orig_hash; |
f45948e8 | 3290 | struct ftrace_hash *hash; |
33dc9b12 | 3291 | int ret; |
f45948e8 | 3292 | |
936e074b SR |
3293 | /* All global ops uses the global ops filters */ |
3294 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) | |
3295 | ops = &global_ops; | |
3296 | ||
41c52c0d | 3297 | if (unlikely(ftrace_disabled)) |
33dc9b12 | 3298 | return -ENODEV; |
41c52c0d | 3299 | |
f45948e8 | 3300 | if (enable) |
33dc9b12 | 3301 | orig_hash = &ops->filter_hash; |
f45948e8 | 3302 | else |
33dc9b12 SR |
3303 | orig_hash = &ops->notrace_hash; |
3304 | ||
3305 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
3306 | if (!hash) | |
3307 | return -ENOMEM; | |
f45948e8 | 3308 | |
41c52c0d SR |
3309 | mutex_lock(&ftrace_regex_lock); |
3310 | if (reset) | |
1cf41dd7 | 3311 | ftrace_filter_reset(hash); |
ac483c44 JO |
3312 | if (buf && !ftrace_match_records(hash, buf, len)) { |
3313 | ret = -EINVAL; | |
3314 | goto out_regex_unlock; | |
3315 | } | |
647664ea MH |
3316 | if (ip) { |
3317 | ret = ftrace_match_addr(hash, ip, remove); | |
3318 | if (ret < 0) | |
3319 | goto out_regex_unlock; | |
3320 | } | |
33dc9b12 SR |
3321 | |
3322 | mutex_lock(&ftrace_lock); | |
41fb61c2 | 3323 | ret = ftrace_hash_move(ops, enable, orig_hash, hash); |
072126f4 SR |
3324 | if (!ret && ops->flags & FTRACE_OPS_FL_ENABLED |
3325 | && ftrace_enabled) | |
30fb6aa7 | 3326 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); |
072126f4 | 3327 | |
33dc9b12 SR |
3328 | mutex_unlock(&ftrace_lock); |
3329 | ||
ac483c44 | 3330 | out_regex_unlock: |
41c52c0d | 3331 | mutex_unlock(&ftrace_regex_lock); |
33dc9b12 SR |
3332 | |
3333 | free_ftrace_hash(hash); | |
3334 | return ret; | |
41c52c0d SR |
3335 | } |
3336 | ||
647664ea MH |
3337 | static int |
3338 | ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove, | |
3339 | int reset, int enable) | |
3340 | { | |
3341 | return ftrace_set_hash(ops, 0, 0, ip, remove, reset, enable); | |
3342 | } | |
3343 | ||
3344 | /** | |
3345 | * ftrace_set_filter_ip - set a function to filter on in ftrace by address | |
3346 | * @ops - the ops to set the filter with | |
3347 | * @ip - the address to add to or remove from the filter. | |
3348 | * @remove - non zero to remove the ip from the filter | |
3349 | * @reset - non zero to reset all filters before applying this filter. | |
3350 | * | |
3351 | * Filters denote which functions should be enabled when tracing is enabled | |
3352 | * If @ip is NULL, it failes to update filter. | |
3353 | */ | |
3354 | int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, | |
3355 | int remove, int reset) | |
3356 | { | |
3357 | return ftrace_set_addr(ops, ip, remove, reset, 1); | |
3358 | } | |
3359 | EXPORT_SYMBOL_GPL(ftrace_set_filter_ip); | |
3360 | ||
3361 | static int | |
3362 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, | |
3363 | int reset, int enable) | |
3364 | { | |
3365 | return ftrace_set_hash(ops, buf, len, 0, 0, reset, enable); | |
3366 | } | |
3367 | ||
77a2b37d SR |
3368 | /** |
3369 | * ftrace_set_filter - set a function to filter on in ftrace | |
936e074b SR |
3370 | * @ops - the ops to set the filter with |
3371 | * @buf - the string that holds the function filter text. | |
3372 | * @len - the length of the string. | |
3373 | * @reset - non zero to reset all filters before applying this filter. | |
3374 | * | |
3375 | * Filters denote which functions should be enabled when tracing is enabled. | |
3376 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
3377 | */ | |
ac483c44 | 3378 | int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
3379 | int len, int reset) |
3380 | { | |
ac483c44 | 3381 | return ftrace_set_regex(ops, buf, len, reset, 1); |
936e074b SR |
3382 | } |
3383 | EXPORT_SYMBOL_GPL(ftrace_set_filter); | |
3384 | ||
3385 | /** | |
3386 | * ftrace_set_notrace - set a function to not trace in ftrace | |
3387 | * @ops - the ops to set the notrace filter with | |
3388 | * @buf - the string that holds the function notrace text. | |
3389 | * @len - the length of the string. | |
3390 | * @reset - non zero to reset all filters before applying this filter. | |
3391 | * | |
3392 | * Notrace Filters denote which functions should not be enabled when tracing | |
3393 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
3394 | * for tracing. | |
3395 | */ | |
ac483c44 | 3396 | int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
3397 | int len, int reset) |
3398 | { | |
ac483c44 | 3399 | return ftrace_set_regex(ops, buf, len, reset, 0); |
936e074b SR |
3400 | } |
3401 | EXPORT_SYMBOL_GPL(ftrace_set_notrace); | |
3402 | /** | |
3403 | * ftrace_set_filter - set a function to filter on in ftrace | |
3404 | * @ops - the ops to set the filter with | |
77a2b37d SR |
3405 | * @buf - the string that holds the function filter text. |
3406 | * @len - the length of the string. | |
3407 | * @reset - non zero to reset all filters before applying this filter. | |
3408 | * | |
3409 | * Filters denote which functions should be enabled when tracing is enabled. | |
3410 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
3411 | */ | |
936e074b | 3412 | void ftrace_set_global_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 3413 | { |
f45948e8 | 3414 | ftrace_set_regex(&global_ops, buf, len, reset, 1); |
41c52c0d | 3415 | } |
936e074b | 3416 | EXPORT_SYMBOL_GPL(ftrace_set_global_filter); |
4eebcc81 | 3417 | |
41c52c0d SR |
3418 | /** |
3419 | * ftrace_set_notrace - set a function to not trace in ftrace | |
936e074b | 3420 | * @ops - the ops to set the notrace filter with |
41c52c0d SR |
3421 | * @buf - the string that holds the function notrace text. |
3422 | * @len - the length of the string. | |
3423 | * @reset - non zero to reset all filters before applying this filter. | |
3424 | * | |
3425 | * Notrace Filters denote which functions should not be enabled when tracing | |
3426 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
3427 | * for tracing. | |
3428 | */ | |
936e074b | 3429 | void ftrace_set_global_notrace(unsigned char *buf, int len, int reset) |
41c52c0d | 3430 | { |
f45948e8 | 3431 | ftrace_set_regex(&global_ops, buf, len, reset, 0); |
77a2b37d | 3432 | } |
936e074b | 3433 | EXPORT_SYMBOL_GPL(ftrace_set_global_notrace); |
77a2b37d | 3434 | |
2af15d6a SR |
3435 | /* |
3436 | * command line interface to allow users to set filters on boot up. | |
3437 | */ | |
3438 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE | |
3439 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; | |
3440 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; | |
3441 | ||
3442 | static int __init set_ftrace_notrace(char *str) | |
3443 | { | |
3444 | strncpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); | |
3445 | return 1; | |
3446 | } | |
3447 | __setup("ftrace_notrace=", set_ftrace_notrace); | |
3448 | ||
3449 | static int __init set_ftrace_filter(char *str) | |
3450 | { | |
3451 | strncpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); | |
3452 | return 1; | |
3453 | } | |
3454 | __setup("ftrace_filter=", set_ftrace_filter); | |
3455 | ||
369bc18f | 3456 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
f6060f46 | 3457 | static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; |
801c29fd SR |
3458 | static int ftrace_set_func(unsigned long *array, int *idx, char *buffer); |
3459 | ||
369bc18f SA |
3460 | static int __init set_graph_function(char *str) |
3461 | { | |
06f43d66 | 3462 | strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); |
369bc18f SA |
3463 | return 1; |
3464 | } | |
3465 | __setup("ftrace_graph_filter=", set_graph_function); | |
3466 | ||
3467 | static void __init set_ftrace_early_graph(char *buf) | |
3468 | { | |
3469 | int ret; | |
3470 | char *func; | |
3471 | ||
3472 | while (buf) { | |
3473 | func = strsep(&buf, ","); | |
3474 | /* we allow only one expression at a time */ | |
3475 | ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, | |
3476 | func); | |
3477 | if (ret) | |
3478 | printk(KERN_DEBUG "ftrace: function %s not " | |
3479 | "traceable\n", func); | |
3480 | } | |
3481 | } | |
3482 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
3483 | ||
2a85a37f SR |
3484 | void __init |
3485 | ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable) | |
2af15d6a SR |
3486 | { |
3487 | char *func; | |
3488 | ||
3489 | while (buf) { | |
3490 | func = strsep(&buf, ","); | |
f45948e8 | 3491 | ftrace_set_regex(ops, func, strlen(func), 0, enable); |
2af15d6a SR |
3492 | } |
3493 | } | |
3494 | ||
3495 | static void __init set_ftrace_early_filters(void) | |
3496 | { | |
3497 | if (ftrace_filter_buf[0]) | |
2a85a37f | 3498 | ftrace_set_early_filter(&global_ops, ftrace_filter_buf, 1); |
2af15d6a | 3499 | if (ftrace_notrace_buf[0]) |
2a85a37f | 3500 | ftrace_set_early_filter(&global_ops, ftrace_notrace_buf, 0); |
369bc18f SA |
3501 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
3502 | if (ftrace_graph_buf[0]) | |
3503 | set_ftrace_early_graph(ftrace_graph_buf); | |
3504 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
2af15d6a SR |
3505 | } |
3506 | ||
fc13cb0c | 3507 | int ftrace_regex_release(struct inode *inode, struct file *file) |
5072c59f SR |
3508 | { |
3509 | struct seq_file *m = (struct seq_file *)file->private_data; | |
3510 | struct ftrace_iterator *iter; | |
33dc9b12 | 3511 | struct ftrace_hash **orig_hash; |
689fd8b6 | 3512 | struct trace_parser *parser; |
ed926f9b | 3513 | int filter_hash; |
33dc9b12 | 3514 | int ret; |
5072c59f | 3515 | |
41c52c0d | 3516 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
3517 | if (file->f_mode & FMODE_READ) { |
3518 | iter = m->private; | |
3519 | ||
3520 | seq_release(inode, file); | |
3521 | } else | |
3522 | iter = file->private_data; | |
3523 | ||
689fd8b6 | 3524 | parser = &iter->parser; |
3525 | if (trace_parser_loaded(parser)) { | |
3526 | parser->buffer[parser->idx] = 0; | |
1cf41dd7 | 3527 | ftrace_match_records(iter->hash, parser->buffer, parser->idx); |
5072c59f SR |
3528 | } |
3529 | ||
689fd8b6 | 3530 | trace_parser_put(parser); |
689fd8b6 | 3531 | |
058e297d | 3532 | if (file->f_mode & FMODE_WRITE) { |
ed926f9b SR |
3533 | filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); |
3534 | ||
3535 | if (filter_hash) | |
33dc9b12 | 3536 | orig_hash = &iter->ops->filter_hash; |
ed926f9b SR |
3537 | else |
3538 | orig_hash = &iter->ops->notrace_hash; | |
33dc9b12 | 3539 | |
058e297d | 3540 | mutex_lock(&ftrace_lock); |
41fb61c2 SR |
3541 | ret = ftrace_hash_move(iter->ops, filter_hash, |
3542 | orig_hash, iter->hash); | |
3543 | if (!ret && (iter->ops->flags & FTRACE_OPS_FL_ENABLED) | |
3544 | && ftrace_enabled) | |
30fb6aa7 | 3545 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); |
41fb61c2 | 3546 | |
058e297d SR |
3547 | mutex_unlock(&ftrace_lock); |
3548 | } | |
33dc9b12 SR |
3549 | free_ftrace_hash(iter->hash); |
3550 | kfree(iter); | |
058e297d | 3551 | |
41c52c0d | 3552 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
3553 | return 0; |
3554 | } | |
3555 | ||
5e2336a0 | 3556 | static const struct file_operations ftrace_avail_fops = { |
5072c59f SR |
3557 | .open = ftrace_avail_open, |
3558 | .read = seq_read, | |
3559 | .llseek = seq_lseek, | |
3be04b47 | 3560 | .release = seq_release_private, |
5072c59f SR |
3561 | }; |
3562 | ||
647bcd03 SR |
3563 | static const struct file_operations ftrace_enabled_fops = { |
3564 | .open = ftrace_enabled_open, | |
3565 | .read = seq_read, | |
3566 | .llseek = seq_lseek, | |
3567 | .release = seq_release_private, | |
3568 | }; | |
3569 | ||
5e2336a0 | 3570 | static const struct file_operations ftrace_filter_fops = { |
5072c59f | 3571 | .open = ftrace_filter_open, |
850a80cf | 3572 | .read = seq_read, |
5072c59f | 3573 | .write = ftrace_filter_write, |
98c4fd04 | 3574 | .llseek = ftrace_regex_lseek, |
1cf41dd7 | 3575 | .release = ftrace_regex_release, |
5072c59f SR |
3576 | }; |
3577 | ||
5e2336a0 | 3578 | static const struct file_operations ftrace_notrace_fops = { |
41c52c0d | 3579 | .open = ftrace_notrace_open, |
850a80cf | 3580 | .read = seq_read, |
41c52c0d SR |
3581 | .write = ftrace_notrace_write, |
3582 | .llseek = ftrace_regex_lseek, | |
1cf41dd7 | 3583 | .release = ftrace_regex_release, |
41c52c0d SR |
3584 | }; |
3585 | ||
ea4e2bc4 SR |
3586 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
3587 | ||
3588 | static DEFINE_MUTEX(graph_lock); | |
3589 | ||
3590 | int ftrace_graph_count; | |
c7c6b1fe | 3591 | int ftrace_graph_filter_enabled; |
ea4e2bc4 SR |
3592 | unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; |
3593 | ||
3594 | static void * | |
85951842 | 3595 | __g_next(struct seq_file *m, loff_t *pos) |
ea4e2bc4 | 3596 | { |
85951842 | 3597 | if (*pos >= ftrace_graph_count) |
ea4e2bc4 | 3598 | return NULL; |
a4ec5e0c | 3599 | return &ftrace_graph_funcs[*pos]; |
85951842 | 3600 | } |
ea4e2bc4 | 3601 | |
85951842 LZ |
3602 | static void * |
3603 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
3604 | { | |
3605 | (*pos)++; | |
3606 | return __g_next(m, pos); | |
ea4e2bc4 SR |
3607 | } |
3608 | ||
3609 | static void *g_start(struct seq_file *m, loff_t *pos) | |
3610 | { | |
ea4e2bc4 SR |
3611 | mutex_lock(&graph_lock); |
3612 | ||
f9349a8f | 3613 | /* Nothing, tell g_show to print all functions are enabled */ |
c7c6b1fe | 3614 | if (!ftrace_graph_filter_enabled && !*pos) |
f9349a8f FW |
3615 | return (void *)1; |
3616 | ||
85951842 | 3617 | return __g_next(m, pos); |
ea4e2bc4 SR |
3618 | } |
3619 | ||
3620 | static void g_stop(struct seq_file *m, void *p) | |
3621 | { | |
3622 | mutex_unlock(&graph_lock); | |
3623 | } | |
3624 | ||
3625 | static int g_show(struct seq_file *m, void *v) | |
3626 | { | |
3627 | unsigned long *ptr = v; | |
ea4e2bc4 SR |
3628 | |
3629 | if (!ptr) | |
3630 | return 0; | |
3631 | ||
f9349a8f FW |
3632 | if (ptr == (unsigned long *)1) { |
3633 | seq_printf(m, "#### all functions enabled ####\n"); | |
3634 | return 0; | |
3635 | } | |
3636 | ||
b375a11a | 3637 | seq_printf(m, "%ps\n", (void *)*ptr); |
ea4e2bc4 SR |
3638 | |
3639 | return 0; | |
3640 | } | |
3641 | ||
88e9d34c | 3642 | static const struct seq_operations ftrace_graph_seq_ops = { |
ea4e2bc4 SR |
3643 | .start = g_start, |
3644 | .next = g_next, | |
3645 | .stop = g_stop, | |
3646 | .show = g_show, | |
3647 | }; | |
3648 | ||
3649 | static int | |
3650 | ftrace_graph_open(struct inode *inode, struct file *file) | |
3651 | { | |
3652 | int ret = 0; | |
3653 | ||
3654 | if (unlikely(ftrace_disabled)) | |
3655 | return -ENODEV; | |
3656 | ||
3657 | mutex_lock(&graph_lock); | |
3658 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 3659 | (file->f_flags & O_TRUNC)) { |
c7c6b1fe | 3660 | ftrace_graph_filter_enabled = 0; |
ea4e2bc4 SR |
3661 | ftrace_graph_count = 0; |
3662 | memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); | |
3663 | } | |
a4ec5e0c | 3664 | mutex_unlock(&graph_lock); |
ea4e2bc4 | 3665 | |
a4ec5e0c | 3666 | if (file->f_mode & FMODE_READ) |
ea4e2bc4 | 3667 | ret = seq_open(file, &ftrace_graph_seq_ops); |
ea4e2bc4 SR |
3668 | |
3669 | return ret; | |
3670 | } | |
3671 | ||
87827111 LZ |
3672 | static int |
3673 | ftrace_graph_release(struct inode *inode, struct file *file) | |
3674 | { | |
3675 | if (file->f_mode & FMODE_READ) | |
3676 | seq_release(inode, file); | |
3677 | return 0; | |
3678 | } | |
3679 | ||
ea4e2bc4 | 3680 | static int |
f9349a8f | 3681 | ftrace_set_func(unsigned long *array, int *idx, char *buffer) |
ea4e2bc4 | 3682 | { |
ea4e2bc4 SR |
3683 | struct dyn_ftrace *rec; |
3684 | struct ftrace_page *pg; | |
f9349a8f | 3685 | int search_len; |
c7c6b1fe | 3686 | int fail = 1; |
f9349a8f FW |
3687 | int type, not; |
3688 | char *search; | |
3689 | bool exists; | |
3690 | int i; | |
ea4e2bc4 | 3691 | |
f9349a8f | 3692 | /* decode regex */ |
3f6fe06d | 3693 | type = filter_parse_regex(buffer, strlen(buffer), &search, ¬); |
c7c6b1fe LZ |
3694 | if (!not && *idx >= FTRACE_GRAPH_MAX_FUNCS) |
3695 | return -EBUSY; | |
f9349a8f FW |
3696 | |
3697 | search_len = strlen(search); | |
3698 | ||
52baf119 | 3699 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
3700 | |
3701 | if (unlikely(ftrace_disabled)) { | |
3702 | mutex_unlock(&ftrace_lock); | |
3703 | return -ENODEV; | |
3704 | } | |
3705 | ||
265c831c SR |
3706 | do_for_each_ftrace_rec(pg, rec) { |
3707 | ||
b9df92d2 | 3708 | if (ftrace_match_record(rec, NULL, search, search_len, type)) { |
c7c6b1fe | 3709 | /* if it is in the array */ |
f9349a8f | 3710 | exists = false; |
c7c6b1fe | 3711 | for (i = 0; i < *idx; i++) { |
f9349a8f FW |
3712 | if (array[i] == rec->ip) { |
3713 | exists = true; | |
265c831c SR |
3714 | break; |
3715 | } | |
c7c6b1fe LZ |
3716 | } |
3717 | ||
3718 | if (!not) { | |
3719 | fail = 0; | |
3720 | if (!exists) { | |
3721 | array[(*idx)++] = rec->ip; | |
3722 | if (*idx >= FTRACE_GRAPH_MAX_FUNCS) | |
3723 | goto out; | |
3724 | } | |
3725 | } else { | |
3726 | if (exists) { | |
3727 | array[i] = array[--(*idx)]; | |
3728 | array[*idx] = 0; | |
3729 | fail = 0; | |
3730 | } | |
3731 | } | |
ea4e2bc4 | 3732 | } |
265c831c | 3733 | } while_for_each_ftrace_rec(); |
c7c6b1fe | 3734 | out: |
52baf119 | 3735 | mutex_unlock(&ftrace_lock); |
ea4e2bc4 | 3736 | |
c7c6b1fe LZ |
3737 | if (fail) |
3738 | return -EINVAL; | |
3739 | ||
3740 | ftrace_graph_filter_enabled = 1; | |
3741 | return 0; | |
ea4e2bc4 SR |
3742 | } |
3743 | ||
3744 | static ssize_t | |
3745 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
3746 | size_t cnt, loff_t *ppos) | |
3747 | { | |
689fd8b6 | 3748 | struct trace_parser parser; |
4ba7978e | 3749 | ssize_t read, ret; |
ea4e2bc4 | 3750 | |
c7c6b1fe | 3751 | if (!cnt) |
ea4e2bc4 SR |
3752 | return 0; |
3753 | ||
3754 | mutex_lock(&graph_lock); | |
3755 | ||
689fd8b6 | 3756 | if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) { |
3757 | ret = -ENOMEM; | |
1eb90f13 | 3758 | goto out_unlock; |
ea4e2bc4 SR |
3759 | } |
3760 | ||
689fd8b6 | 3761 | read = trace_get_user(&parser, ubuf, cnt, ppos); |
ea4e2bc4 | 3762 | |
4ba7978e | 3763 | if (read >= 0 && trace_parser_loaded((&parser))) { |
689fd8b6 | 3764 | parser.buffer[parser.idx] = 0; |
3765 | ||
3766 | /* we allow only one expression at a time */ | |
a4ec5e0c | 3767 | ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, |
689fd8b6 | 3768 | parser.buffer); |
ea4e2bc4 | 3769 | if (ret) |
1eb90f13 | 3770 | goto out_free; |
ea4e2bc4 | 3771 | } |
ea4e2bc4 SR |
3772 | |
3773 | ret = read; | |
1eb90f13 LZ |
3774 | |
3775 | out_free: | |
689fd8b6 | 3776 | trace_parser_put(&parser); |
1eb90f13 | 3777 | out_unlock: |
ea4e2bc4 SR |
3778 | mutex_unlock(&graph_lock); |
3779 | ||
3780 | return ret; | |
3781 | } | |
3782 | ||
3783 | static const struct file_operations ftrace_graph_fops = { | |
87827111 LZ |
3784 | .open = ftrace_graph_open, |
3785 | .read = seq_read, | |
3786 | .write = ftrace_graph_write, | |
3787 | .release = ftrace_graph_release, | |
6038f373 | 3788 | .llseek = seq_lseek, |
ea4e2bc4 SR |
3789 | }; |
3790 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
3791 | ||
df4fc315 | 3792 | static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) |
5072c59f | 3793 | { |
5072c59f | 3794 | |
5452af66 FW |
3795 | trace_create_file("available_filter_functions", 0444, |
3796 | d_tracer, NULL, &ftrace_avail_fops); | |
5072c59f | 3797 | |
647bcd03 SR |
3798 | trace_create_file("enabled_functions", 0444, |
3799 | d_tracer, NULL, &ftrace_enabled_fops); | |
3800 | ||
5452af66 FW |
3801 | trace_create_file("set_ftrace_filter", 0644, d_tracer, |
3802 | NULL, &ftrace_filter_fops); | |
41c52c0d | 3803 | |
5452af66 | 3804 | trace_create_file("set_ftrace_notrace", 0644, d_tracer, |
41c52c0d | 3805 | NULL, &ftrace_notrace_fops); |
ad90c0e3 | 3806 | |
ea4e2bc4 | 3807 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5452af66 | 3808 | trace_create_file("set_graph_function", 0444, d_tracer, |
ea4e2bc4 SR |
3809 | NULL, |
3810 | &ftrace_graph_fops); | |
ea4e2bc4 SR |
3811 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
3812 | ||
5072c59f SR |
3813 | return 0; |
3814 | } | |
3815 | ||
9fd49328 | 3816 | static int ftrace_cmp_ips(const void *a, const void *b) |
68950619 | 3817 | { |
9fd49328 SR |
3818 | const unsigned long *ipa = a; |
3819 | const unsigned long *ipb = b; | |
68950619 | 3820 | |
9fd49328 SR |
3821 | if (*ipa > *ipb) |
3822 | return 1; | |
3823 | if (*ipa < *ipb) | |
3824 | return -1; | |
3825 | return 0; | |
3826 | } | |
3827 | ||
3828 | static void ftrace_swap_ips(void *a, void *b, int size) | |
3829 | { | |
3830 | unsigned long *ipa = a; | |
3831 | unsigned long *ipb = b; | |
3832 | unsigned long t; | |
3833 | ||
3834 | t = *ipa; | |
3835 | *ipa = *ipb; | |
3836 | *ipb = t; | |
68950619 SR |
3837 | } |
3838 | ||
5cb084bb | 3839 | static int ftrace_process_locs(struct module *mod, |
31e88909 | 3840 | unsigned long *start, |
68bf21aa SR |
3841 | unsigned long *end) |
3842 | { | |
706c81f8 | 3843 | struct ftrace_page *start_pg; |
a7900875 | 3844 | struct ftrace_page *pg; |
706c81f8 | 3845 | struct dyn_ftrace *rec; |
a7900875 | 3846 | unsigned long count; |
68bf21aa SR |
3847 | unsigned long *p; |
3848 | unsigned long addr; | |
4376cac6 | 3849 | unsigned long flags = 0; /* Shut up gcc */ |
a7900875 SR |
3850 | int ret = -ENOMEM; |
3851 | ||
3852 | count = end - start; | |
3853 | ||
3854 | if (!count) | |
3855 | return 0; | |
3856 | ||
9fd49328 SR |
3857 | sort(start, count, sizeof(*start), |
3858 | ftrace_cmp_ips, ftrace_swap_ips); | |
3859 | ||
706c81f8 SR |
3860 | start_pg = ftrace_allocate_pages(count); |
3861 | if (!start_pg) | |
a7900875 | 3862 | return -ENOMEM; |
68bf21aa | 3863 | |
e6ea44e9 | 3864 | mutex_lock(&ftrace_lock); |
a7900875 | 3865 | |
32082309 SR |
3866 | /* |
3867 | * Core and each module needs their own pages, as | |
3868 | * modules will free them when they are removed. | |
3869 | * Force a new page to be allocated for modules. | |
3870 | */ | |
a7900875 SR |
3871 | if (!mod) { |
3872 | WARN_ON(ftrace_pages || ftrace_pages_start); | |
3873 | /* First initialization */ | |
706c81f8 | 3874 | ftrace_pages = ftrace_pages_start = start_pg; |
a7900875 | 3875 | } else { |
32082309 | 3876 | if (!ftrace_pages) |
a7900875 | 3877 | goto out; |
32082309 | 3878 | |
a7900875 SR |
3879 | if (WARN_ON(ftrace_pages->next)) { |
3880 | /* Hmm, we have free pages? */ | |
3881 | while (ftrace_pages->next) | |
3882 | ftrace_pages = ftrace_pages->next; | |
32082309 | 3883 | } |
a7900875 | 3884 | |
706c81f8 | 3885 | ftrace_pages->next = start_pg; |
32082309 SR |
3886 | } |
3887 | ||
68bf21aa | 3888 | p = start; |
706c81f8 | 3889 | pg = start_pg; |
68bf21aa SR |
3890 | while (p < end) { |
3891 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
3892 | /* |
3893 | * Some architecture linkers will pad between | |
3894 | * the different mcount_loc sections of different | |
3895 | * object files to satisfy alignments. | |
3896 | * Skip any NULL pointers. | |
3897 | */ | |
3898 | if (!addr) | |
3899 | continue; | |
706c81f8 SR |
3900 | |
3901 | if (pg->index == pg->size) { | |
3902 | /* We should have allocated enough */ | |
3903 | if (WARN_ON(!pg->next)) | |
3904 | break; | |
3905 | pg = pg->next; | |
3906 | } | |
3907 | ||
3908 | rec = &pg->records[pg->index++]; | |
3909 | rec->ip = addr; | |
68bf21aa SR |
3910 | } |
3911 | ||
706c81f8 SR |
3912 | /* We should have used all pages */ |
3913 | WARN_ON(pg->next); | |
3914 | ||
3915 | /* Assign the last page to ftrace_pages */ | |
3916 | ftrace_pages = pg; | |
3917 | ||
85ae32ae | 3918 | /* These new locations need to be initialized */ |
706c81f8 | 3919 | ftrace_new_pgs = start_pg; |
85ae32ae | 3920 | |
a4f18ed1 | 3921 | /* |
4376cac6 SR |
3922 | * We only need to disable interrupts on start up |
3923 | * because we are modifying code that an interrupt | |
3924 | * may execute, and the modification is not atomic. | |
3925 | * But for modules, nothing runs the code we modify | |
3926 | * until we are finished with it, and there's no | |
3927 | * reason to cause large interrupt latencies while we do it. | |
a4f18ed1 | 3928 | */ |
4376cac6 SR |
3929 | if (!mod) |
3930 | local_irq_save(flags); | |
31e88909 | 3931 | ftrace_update_code(mod); |
4376cac6 SR |
3932 | if (!mod) |
3933 | local_irq_restore(flags); | |
a7900875 SR |
3934 | ret = 0; |
3935 | out: | |
e6ea44e9 | 3936 | mutex_unlock(&ftrace_lock); |
68bf21aa | 3937 | |
a7900875 | 3938 | return ret; |
68bf21aa SR |
3939 | } |
3940 | ||
93eb677d | 3941 | #ifdef CONFIG_MODULES |
32082309 SR |
3942 | |
3943 | #define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next) | |
3944 | ||
e7247a15 | 3945 | void ftrace_release_mod(struct module *mod) |
93eb677d SR |
3946 | { |
3947 | struct dyn_ftrace *rec; | |
32082309 | 3948 | struct ftrace_page **last_pg; |
93eb677d | 3949 | struct ftrace_page *pg; |
a7900875 | 3950 | int order; |
93eb677d | 3951 | |
45a4a237 SR |
3952 | mutex_lock(&ftrace_lock); |
3953 | ||
e7247a15 | 3954 | if (ftrace_disabled) |
45a4a237 | 3955 | goto out_unlock; |
93eb677d | 3956 | |
32082309 SR |
3957 | /* |
3958 | * Each module has its own ftrace_pages, remove | |
3959 | * them from the list. | |
3960 | */ | |
3961 | last_pg = &ftrace_pages_start; | |
3962 | for (pg = ftrace_pages_start; pg; pg = *last_pg) { | |
3963 | rec = &pg->records[0]; | |
e7247a15 | 3964 | if (within_module_core(rec->ip, mod)) { |
93eb677d | 3965 | /* |
32082309 SR |
3966 | * As core pages are first, the first |
3967 | * page should never be a module page. | |
93eb677d | 3968 | */ |
32082309 SR |
3969 | if (WARN_ON(pg == ftrace_pages_start)) |
3970 | goto out_unlock; | |
3971 | ||
3972 | /* Check if we are deleting the last page */ | |
3973 | if (pg == ftrace_pages) | |
3974 | ftrace_pages = next_to_ftrace_page(last_pg); | |
3975 | ||
3976 | *last_pg = pg->next; | |
a7900875 SR |
3977 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); |
3978 | free_pages((unsigned long)pg->records, order); | |
3979 | kfree(pg); | |
32082309 SR |
3980 | } else |
3981 | last_pg = &pg->next; | |
3982 | } | |
45a4a237 | 3983 | out_unlock: |
93eb677d SR |
3984 | mutex_unlock(&ftrace_lock); |
3985 | } | |
3986 | ||
3987 | static void ftrace_init_module(struct module *mod, | |
3988 | unsigned long *start, unsigned long *end) | |
90d595fe | 3989 | { |
00fd61ae | 3990 | if (ftrace_disabled || start == end) |
fed1939c | 3991 | return; |
5cb084bb | 3992 | ftrace_process_locs(mod, start, end); |
90d595fe SR |
3993 | } |
3994 | ||
8c189ea6 SRRH |
3995 | static int ftrace_module_notify_enter(struct notifier_block *self, |
3996 | unsigned long val, void *data) | |
93eb677d SR |
3997 | { |
3998 | struct module *mod = data; | |
3999 | ||
8c189ea6 | 4000 | if (val == MODULE_STATE_COMING) |
93eb677d SR |
4001 | ftrace_init_module(mod, mod->ftrace_callsites, |
4002 | mod->ftrace_callsites + | |
4003 | mod->num_ftrace_callsites); | |
8c189ea6 SRRH |
4004 | return 0; |
4005 | } | |
4006 | ||
4007 | static int ftrace_module_notify_exit(struct notifier_block *self, | |
4008 | unsigned long val, void *data) | |
4009 | { | |
4010 | struct module *mod = data; | |
4011 | ||
4012 | if (val == MODULE_STATE_GOING) | |
e7247a15 | 4013 | ftrace_release_mod(mod); |
93eb677d SR |
4014 | |
4015 | return 0; | |
4016 | } | |
4017 | #else | |
8c189ea6 SRRH |
4018 | static int ftrace_module_notify_enter(struct notifier_block *self, |
4019 | unsigned long val, void *data) | |
4020 | { | |
4021 | return 0; | |
4022 | } | |
4023 | static int ftrace_module_notify_exit(struct notifier_block *self, | |
4024 | unsigned long val, void *data) | |
93eb677d SR |
4025 | { |
4026 | return 0; | |
4027 | } | |
4028 | #endif /* CONFIG_MODULES */ | |
4029 | ||
8c189ea6 SRRH |
4030 | struct notifier_block ftrace_module_enter_nb = { |
4031 | .notifier_call = ftrace_module_notify_enter, | |
c1bf08ac | 4032 | .priority = INT_MAX, /* Run before anything that can use kprobes */ |
93eb677d SR |
4033 | }; |
4034 | ||
8c189ea6 SRRH |
4035 | struct notifier_block ftrace_module_exit_nb = { |
4036 | .notifier_call = ftrace_module_notify_exit, | |
4037 | .priority = INT_MIN, /* Run after anything that can remove kprobes */ | |
4038 | }; | |
4039 | ||
68bf21aa SR |
4040 | extern unsigned long __start_mcount_loc[]; |
4041 | extern unsigned long __stop_mcount_loc[]; | |
4042 | ||
4043 | void __init ftrace_init(void) | |
4044 | { | |
4045 | unsigned long count, addr, flags; | |
4046 | int ret; | |
4047 | ||
4048 | /* Keep the ftrace pointer to the stub */ | |
4049 | addr = (unsigned long)ftrace_stub; | |
4050 | ||
4051 | local_irq_save(flags); | |
4052 | ftrace_dyn_arch_init(&addr); | |
4053 | local_irq_restore(flags); | |
4054 | ||
4055 | /* ftrace_dyn_arch_init places the return code in addr */ | |
4056 | if (addr) | |
4057 | goto failed; | |
4058 | ||
4059 | count = __stop_mcount_loc - __start_mcount_loc; | |
4060 | ||
4061 | ret = ftrace_dyn_table_alloc(count); | |
4062 | if (ret) | |
4063 | goto failed; | |
4064 | ||
4065 | last_ftrace_enabled = ftrace_enabled = 1; | |
4066 | ||
5cb084bb | 4067 | ret = ftrace_process_locs(NULL, |
31e88909 | 4068 | __start_mcount_loc, |
68bf21aa SR |
4069 | __stop_mcount_loc); |
4070 | ||
8c189ea6 SRRH |
4071 | ret = register_module_notifier(&ftrace_module_enter_nb); |
4072 | if (ret) | |
4073 | pr_warning("Failed to register trace ftrace module enter notifier\n"); | |
4074 | ||
4075 | ret = register_module_notifier(&ftrace_module_exit_nb); | |
24ed0c4b | 4076 | if (ret) |
8c189ea6 | 4077 | pr_warning("Failed to register trace ftrace module exit notifier\n"); |
93eb677d | 4078 | |
2af15d6a SR |
4079 | set_ftrace_early_filters(); |
4080 | ||
68bf21aa SR |
4081 | return; |
4082 | failed: | |
4083 | ftrace_disabled = 1; | |
4084 | } | |
68bf21aa | 4085 | |
3d083395 | 4086 | #else |
0b6e4d56 | 4087 | |
2b499381 | 4088 | static struct ftrace_ops global_ops = { |
bd69c30b | 4089 | .func = ftrace_stub, |
4740974a | 4090 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
bd69c30b SR |
4091 | }; |
4092 | ||
0b6e4d56 FW |
4093 | static int __init ftrace_nodyn_init(void) |
4094 | { | |
4095 | ftrace_enabled = 1; | |
4096 | return 0; | |
4097 | } | |
6f415672 | 4098 | core_initcall(ftrace_nodyn_init); |
0b6e4d56 | 4099 | |
df4fc315 SR |
4100 | static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } |
4101 | static inline void ftrace_startup_enable(int command) { } | |
5a45cfe1 | 4102 | /* Keep as macros so we do not need to define the commands */ |
3b6cfdb1 SR |
4103 | # define ftrace_startup(ops, command) \ |
4104 | ({ \ | |
4105 | (ops)->flags |= FTRACE_OPS_FL_ENABLED; \ | |
4106 | 0; \ | |
4107 | }) | |
bd69c30b | 4108 | # define ftrace_shutdown(ops, command) do { } while (0) |
c7aafc54 IM |
4109 | # define ftrace_startup_sysctl() do { } while (0) |
4110 | # define ftrace_shutdown_sysctl() do { } while (0) | |
b848914c SR |
4111 | |
4112 | static inline int | |
4113 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip) | |
4114 | { | |
4115 | return 1; | |
4116 | } | |
4117 | ||
3d083395 SR |
4118 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
4119 | ||
e248491a | 4120 | static void |
2f5f6ad9 | 4121 | ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 4122 | struct ftrace_ops *op, struct pt_regs *regs) |
e248491a | 4123 | { |
e248491a JO |
4124 | if (unlikely(trace_recursion_test(TRACE_CONTROL_BIT))) |
4125 | return; | |
4126 | ||
4127 | /* | |
4128 | * Some of the ops may be dynamically allocated, | |
4129 | * they must be freed after a synchronize_sched(). | |
4130 | */ | |
4131 | preempt_disable_notrace(); | |
4132 | trace_recursion_set(TRACE_CONTROL_BIT); | |
0a016409 | 4133 | do_for_each_ftrace_op(op, ftrace_control_list) { |
e248491a JO |
4134 | if (!ftrace_function_local_disabled(op) && |
4135 | ftrace_ops_test(op, ip)) | |
a1e2e31d | 4136 | op->func(ip, parent_ip, op, regs); |
0a016409 | 4137 | } while_for_each_ftrace_op(op); |
e248491a JO |
4138 | trace_recursion_clear(TRACE_CONTROL_BIT); |
4139 | preempt_enable_notrace(); | |
4140 | } | |
4141 | ||
4142 | static struct ftrace_ops control_ops = { | |
4143 | .func = ftrace_ops_control_func, | |
4740974a | 4144 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
e248491a JO |
4145 | }; |
4146 | ||
2f5f6ad9 SR |
4147 | static inline void |
4148 | __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 4149 | struct ftrace_ops *ignored, struct pt_regs *regs) |
b848914c | 4150 | { |
cdbe61bf | 4151 | struct ftrace_ops *op; |
edc15caf | 4152 | int bit; |
b848914c | 4153 | |
ccf3672d SR |
4154 | if (function_trace_stop) |
4155 | return; | |
4156 | ||
edc15caf SR |
4157 | bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); |
4158 | if (bit < 0) | |
4159 | return; | |
b1cff0ad | 4160 | |
cdbe61bf SR |
4161 | /* |
4162 | * Some of the ops may be dynamically allocated, | |
4163 | * they must be freed after a synchronize_sched(). | |
4164 | */ | |
4165 | preempt_disable_notrace(); | |
0a016409 | 4166 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
b848914c | 4167 | if (ftrace_ops_test(op, ip)) |
a1e2e31d | 4168 | op->func(ip, parent_ip, op, regs); |
0a016409 | 4169 | } while_for_each_ftrace_op(op); |
cdbe61bf | 4170 | preempt_enable_notrace(); |
edc15caf | 4171 | trace_clear_recursion(bit); |
b848914c SR |
4172 | } |
4173 | ||
2f5f6ad9 SR |
4174 | /* |
4175 | * Some archs only support passing ip and parent_ip. Even though | |
4176 | * the list function ignores the op parameter, we do not want any | |
4177 | * C side effects, where a function is called without the caller | |
4178 | * sending a third parameter. | |
a1e2e31d SR |
4179 | * Archs are to support both the regs and ftrace_ops at the same time. |
4180 | * If they support ftrace_ops, it is assumed they support regs. | |
4181 | * If call backs want to use regs, they must either check for regs | |
06aeaaea MH |
4182 | * being NULL, or CONFIG_DYNAMIC_FTRACE_WITH_REGS. |
4183 | * Note, CONFIG_DYNAMIC_FTRACE_WITH_REGS expects a full regs to be saved. | |
a1e2e31d SR |
4184 | * An architecture can pass partial regs with ftrace_ops and still |
4185 | * set the ARCH_SUPPORT_FTARCE_OPS. | |
2f5f6ad9 SR |
4186 | */ |
4187 | #if ARCH_SUPPORTS_FTRACE_OPS | |
4188 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 4189 | struct ftrace_ops *op, struct pt_regs *regs) |
2f5f6ad9 | 4190 | { |
a1e2e31d | 4191 | __ftrace_ops_list_func(ip, parent_ip, NULL, regs); |
2f5f6ad9 SR |
4192 | } |
4193 | #else | |
4194 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip) | |
4195 | { | |
a1e2e31d | 4196 | __ftrace_ops_list_func(ip, parent_ip, NULL, NULL); |
2f5f6ad9 SR |
4197 | } |
4198 | #endif | |
4199 | ||
e32d8956 | 4200 | static void clear_ftrace_swapper(void) |
978f3a45 SR |
4201 | { |
4202 | struct task_struct *p; | |
e32d8956 | 4203 | int cpu; |
978f3a45 | 4204 | |
e32d8956 SR |
4205 | get_online_cpus(); |
4206 | for_each_online_cpu(cpu) { | |
4207 | p = idle_task(cpu); | |
978f3a45 | 4208 | clear_tsk_trace_trace(p); |
e32d8956 SR |
4209 | } |
4210 | put_online_cpus(); | |
4211 | } | |
978f3a45 | 4212 | |
e32d8956 SR |
4213 | static void set_ftrace_swapper(void) |
4214 | { | |
4215 | struct task_struct *p; | |
4216 | int cpu; | |
4217 | ||
4218 | get_online_cpus(); | |
4219 | for_each_online_cpu(cpu) { | |
4220 | p = idle_task(cpu); | |
4221 | set_tsk_trace_trace(p); | |
4222 | } | |
4223 | put_online_cpus(); | |
978f3a45 SR |
4224 | } |
4225 | ||
e32d8956 SR |
4226 | static void clear_ftrace_pid(struct pid *pid) |
4227 | { | |
4228 | struct task_struct *p; | |
4229 | ||
229c4ef8 | 4230 | rcu_read_lock(); |
e32d8956 SR |
4231 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
4232 | clear_tsk_trace_trace(p); | |
4233 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 ON |
4234 | rcu_read_unlock(); |
4235 | ||
e32d8956 SR |
4236 | put_pid(pid); |
4237 | } | |
4238 | ||
4239 | static void set_ftrace_pid(struct pid *pid) | |
978f3a45 SR |
4240 | { |
4241 | struct task_struct *p; | |
4242 | ||
229c4ef8 | 4243 | rcu_read_lock(); |
978f3a45 SR |
4244 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
4245 | set_tsk_trace_trace(p); | |
4246 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 | 4247 | rcu_read_unlock(); |
978f3a45 SR |
4248 | } |
4249 | ||
756d17ee | 4250 | static void clear_ftrace_pid_task(struct pid *pid) |
e32d8956 | 4251 | { |
756d17ee | 4252 | if (pid == ftrace_swapper_pid) |
e32d8956 SR |
4253 | clear_ftrace_swapper(); |
4254 | else | |
756d17ee | 4255 | clear_ftrace_pid(pid); |
e32d8956 SR |
4256 | } |
4257 | ||
4258 | static void set_ftrace_pid_task(struct pid *pid) | |
4259 | { | |
4260 | if (pid == ftrace_swapper_pid) | |
4261 | set_ftrace_swapper(); | |
4262 | else | |
4263 | set_ftrace_pid(pid); | |
4264 | } | |
4265 | ||
756d17ee | 4266 | static int ftrace_pid_add(int p) |
df4fc315 | 4267 | { |
978f3a45 | 4268 | struct pid *pid; |
756d17ee | 4269 | struct ftrace_pid *fpid; |
4270 | int ret = -EINVAL; | |
df4fc315 | 4271 | |
756d17ee | 4272 | mutex_lock(&ftrace_lock); |
df4fc315 | 4273 | |
756d17ee | 4274 | if (!p) |
4275 | pid = ftrace_swapper_pid; | |
4276 | else | |
4277 | pid = find_get_pid(p); | |
df4fc315 | 4278 | |
756d17ee | 4279 | if (!pid) |
4280 | goto out; | |
df4fc315 | 4281 | |
756d17ee | 4282 | ret = 0; |
df4fc315 | 4283 | |
756d17ee | 4284 | list_for_each_entry(fpid, &ftrace_pids, list) |
4285 | if (fpid->pid == pid) | |
4286 | goto out_put; | |
978f3a45 | 4287 | |
756d17ee | 4288 | ret = -ENOMEM; |
df4fc315 | 4289 | |
756d17ee | 4290 | fpid = kmalloc(sizeof(*fpid), GFP_KERNEL); |
4291 | if (!fpid) | |
4292 | goto out_put; | |
df4fc315 | 4293 | |
756d17ee | 4294 | list_add(&fpid->list, &ftrace_pids); |
4295 | fpid->pid = pid; | |
0ef8cde5 | 4296 | |
756d17ee | 4297 | set_ftrace_pid_task(pid); |
978f3a45 | 4298 | |
756d17ee | 4299 | ftrace_update_pid_func(); |
4300 | ftrace_startup_enable(0); | |
4301 | ||
4302 | mutex_unlock(&ftrace_lock); | |
4303 | return 0; | |
4304 | ||
4305 | out_put: | |
4306 | if (pid != ftrace_swapper_pid) | |
4307 | put_pid(pid); | |
978f3a45 | 4308 | |
756d17ee | 4309 | out: |
4310 | mutex_unlock(&ftrace_lock); | |
4311 | return ret; | |
4312 | } | |
4313 | ||
4314 | static void ftrace_pid_reset(void) | |
4315 | { | |
4316 | struct ftrace_pid *fpid, *safe; | |
978f3a45 | 4317 | |
756d17ee | 4318 | mutex_lock(&ftrace_lock); |
4319 | list_for_each_entry_safe(fpid, safe, &ftrace_pids, list) { | |
4320 | struct pid *pid = fpid->pid; | |
4321 | ||
4322 | clear_ftrace_pid_task(pid); | |
4323 | ||
4324 | list_del(&fpid->list); | |
4325 | kfree(fpid); | |
df4fc315 SR |
4326 | } |
4327 | ||
df4fc315 SR |
4328 | ftrace_update_pid_func(); |
4329 | ftrace_startup_enable(0); | |
4330 | ||
e6ea44e9 | 4331 | mutex_unlock(&ftrace_lock); |
756d17ee | 4332 | } |
df4fc315 | 4333 | |
756d17ee | 4334 | static void *fpid_start(struct seq_file *m, loff_t *pos) |
4335 | { | |
4336 | mutex_lock(&ftrace_lock); | |
4337 | ||
4338 | if (list_empty(&ftrace_pids) && (!*pos)) | |
4339 | return (void *) 1; | |
4340 | ||
4341 | return seq_list_start(&ftrace_pids, *pos); | |
4342 | } | |
4343 | ||
4344 | static void *fpid_next(struct seq_file *m, void *v, loff_t *pos) | |
4345 | { | |
4346 | if (v == (void *)1) | |
4347 | return NULL; | |
4348 | ||
4349 | return seq_list_next(v, &ftrace_pids, pos); | |
4350 | } | |
4351 | ||
4352 | static void fpid_stop(struct seq_file *m, void *p) | |
4353 | { | |
4354 | mutex_unlock(&ftrace_lock); | |
4355 | } | |
4356 | ||
4357 | static int fpid_show(struct seq_file *m, void *v) | |
4358 | { | |
4359 | const struct ftrace_pid *fpid = list_entry(v, struct ftrace_pid, list); | |
4360 | ||
4361 | if (v == (void *)1) { | |
4362 | seq_printf(m, "no pid\n"); | |
4363 | return 0; | |
4364 | } | |
4365 | ||
4366 | if (fpid->pid == ftrace_swapper_pid) | |
4367 | seq_printf(m, "swapper tasks\n"); | |
4368 | else | |
4369 | seq_printf(m, "%u\n", pid_vnr(fpid->pid)); | |
4370 | ||
4371 | return 0; | |
4372 | } | |
4373 | ||
4374 | static const struct seq_operations ftrace_pid_sops = { | |
4375 | .start = fpid_start, | |
4376 | .next = fpid_next, | |
4377 | .stop = fpid_stop, | |
4378 | .show = fpid_show, | |
4379 | }; | |
4380 | ||
4381 | static int | |
4382 | ftrace_pid_open(struct inode *inode, struct file *file) | |
4383 | { | |
4384 | int ret = 0; | |
4385 | ||
4386 | if ((file->f_mode & FMODE_WRITE) && | |
4387 | (file->f_flags & O_TRUNC)) | |
4388 | ftrace_pid_reset(); | |
4389 | ||
4390 | if (file->f_mode & FMODE_READ) | |
4391 | ret = seq_open(file, &ftrace_pid_sops); | |
4392 | ||
4393 | return ret; | |
4394 | } | |
4395 | ||
df4fc315 SR |
4396 | static ssize_t |
4397 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
4398 | size_t cnt, loff_t *ppos) | |
4399 | { | |
457dc928 | 4400 | char buf[64], *tmp; |
df4fc315 SR |
4401 | long val; |
4402 | int ret; | |
4403 | ||
4404 | if (cnt >= sizeof(buf)) | |
4405 | return -EINVAL; | |
4406 | ||
4407 | if (copy_from_user(&buf, ubuf, cnt)) | |
4408 | return -EFAULT; | |
4409 | ||
4410 | buf[cnt] = 0; | |
4411 | ||
756d17ee | 4412 | /* |
4413 | * Allow "echo > set_ftrace_pid" or "echo -n '' > set_ftrace_pid" | |
4414 | * to clean the filter quietly. | |
4415 | */ | |
457dc928 IM |
4416 | tmp = strstrip(buf); |
4417 | if (strlen(tmp) == 0) | |
756d17ee | 4418 | return 1; |
4419 | ||
bcd83ea6 | 4420 | ret = kstrtol(tmp, 10, &val); |
df4fc315 SR |
4421 | if (ret < 0) |
4422 | return ret; | |
4423 | ||
756d17ee | 4424 | ret = ftrace_pid_add(val); |
df4fc315 | 4425 | |
756d17ee | 4426 | return ret ? ret : cnt; |
4427 | } | |
df4fc315 | 4428 | |
756d17ee | 4429 | static int |
4430 | ftrace_pid_release(struct inode *inode, struct file *file) | |
4431 | { | |
4432 | if (file->f_mode & FMODE_READ) | |
4433 | seq_release(inode, file); | |
df4fc315 | 4434 | |
756d17ee | 4435 | return 0; |
df4fc315 SR |
4436 | } |
4437 | ||
5e2336a0 | 4438 | static const struct file_operations ftrace_pid_fops = { |
756d17ee | 4439 | .open = ftrace_pid_open, |
4440 | .write = ftrace_pid_write, | |
4441 | .read = seq_read, | |
4442 | .llseek = seq_lseek, | |
4443 | .release = ftrace_pid_release, | |
df4fc315 SR |
4444 | }; |
4445 | ||
4446 | static __init int ftrace_init_debugfs(void) | |
4447 | { | |
4448 | struct dentry *d_tracer; | |
df4fc315 SR |
4449 | |
4450 | d_tracer = tracing_init_dentry(); | |
4451 | if (!d_tracer) | |
4452 | return 0; | |
4453 | ||
4454 | ftrace_init_dyn_debugfs(d_tracer); | |
4455 | ||
5452af66 FW |
4456 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
4457 | NULL, &ftrace_pid_fops); | |
493762fc SR |
4458 | |
4459 | ftrace_profile_debugfs(d_tracer); | |
4460 | ||
df4fc315 SR |
4461 | return 0; |
4462 | } | |
df4fc315 SR |
4463 | fs_initcall(ftrace_init_debugfs); |
4464 | ||
a2bb6a3d | 4465 | /** |
81adbdc0 | 4466 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
4467 | * |
4468 | * This function should be used by panic code. It stops ftrace | |
4469 | * but in a not so nice way. If you need to simply kill ftrace | |
4470 | * from a non-atomic section, use ftrace_kill. | |
4471 | */ | |
81adbdc0 | 4472 | void ftrace_kill(void) |
a2bb6a3d SR |
4473 | { |
4474 | ftrace_disabled = 1; | |
4475 | ftrace_enabled = 0; | |
a2bb6a3d SR |
4476 | clear_ftrace_function(); |
4477 | } | |
4478 | ||
e0a413f6 SR |
4479 | /** |
4480 | * Test if ftrace is dead or not. | |
4481 | */ | |
4482 | int ftrace_is_dead(void) | |
4483 | { | |
4484 | return ftrace_disabled; | |
4485 | } | |
4486 | ||
16444a8a | 4487 | /** |
3d083395 SR |
4488 | * register_ftrace_function - register a function for profiling |
4489 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 4490 | * |
3d083395 SR |
4491 | * Register a function to be called by all functions in the |
4492 | * kernel. | |
4493 | * | |
4494 | * Note: @ops->func and all the functions it calls must be labeled | |
4495 | * with "notrace", otherwise it will go into a | |
4496 | * recursive loop. | |
16444a8a | 4497 | */ |
3d083395 | 4498 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 4499 | { |
45a4a237 | 4500 | int ret = -1; |
4eebcc81 | 4501 | |
e6ea44e9 | 4502 | mutex_lock(&ftrace_lock); |
e7d3737e | 4503 | |
b0fc494f | 4504 | ret = __register_ftrace_function(ops); |
b848914c | 4505 | if (!ret) |
a1cd6173 | 4506 | ret = ftrace_startup(ops, 0); |
b848914c | 4507 | |
e6ea44e9 | 4508 | mutex_unlock(&ftrace_lock); |
8d240dd8 | 4509 | |
b0fc494f | 4510 | return ret; |
3d083395 | 4511 | } |
cdbe61bf | 4512 | EXPORT_SYMBOL_GPL(register_ftrace_function); |
3d083395 SR |
4513 | |
4514 | /** | |
32632920 | 4515 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
4516 | * @ops - ops structure that holds the function to unregister |
4517 | * | |
4518 | * Unregister a function that was added to be called by ftrace profiling. | |
4519 | */ | |
4520 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
4521 | { | |
4522 | int ret; | |
4523 | ||
e6ea44e9 | 4524 | mutex_lock(&ftrace_lock); |
3d083395 | 4525 | ret = __unregister_ftrace_function(ops); |
b848914c SR |
4526 | if (!ret) |
4527 | ftrace_shutdown(ops, 0); | |
e6ea44e9 | 4528 | mutex_unlock(&ftrace_lock); |
b0fc494f SR |
4529 | |
4530 | return ret; | |
4531 | } | |
cdbe61bf | 4532 | EXPORT_SYMBOL_GPL(unregister_ftrace_function); |
b0fc494f | 4533 | |
e309b41d | 4534 | int |
b0fc494f | 4535 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
8d65af78 | 4536 | void __user *buffer, size_t *lenp, |
b0fc494f SR |
4537 | loff_t *ppos) |
4538 | { | |
45a4a237 | 4539 | int ret = -ENODEV; |
4eebcc81 | 4540 | |
e6ea44e9 | 4541 | mutex_lock(&ftrace_lock); |
b0fc494f | 4542 | |
45a4a237 SR |
4543 | if (unlikely(ftrace_disabled)) |
4544 | goto out; | |
4545 | ||
4546 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
b0fc494f | 4547 | |
a32c7765 | 4548 | if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) |
b0fc494f SR |
4549 | goto out; |
4550 | ||
a32c7765 | 4551 | last_ftrace_enabled = !!ftrace_enabled; |
b0fc494f SR |
4552 | |
4553 | if (ftrace_enabled) { | |
4554 | ||
4555 | ftrace_startup_sysctl(); | |
4556 | ||
4557 | /* we are starting ftrace again */ | |
b848914c SR |
4558 | if (ftrace_ops_list != &ftrace_list_end) { |
4559 | if (ftrace_ops_list->next == &ftrace_list_end) | |
4560 | ftrace_trace_function = ftrace_ops_list->func; | |
b0fc494f | 4561 | else |
b848914c | 4562 | ftrace_trace_function = ftrace_ops_list_func; |
b0fc494f SR |
4563 | } |
4564 | ||
4565 | } else { | |
4566 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
4567 | ftrace_trace_function = ftrace_stub; | |
4568 | ||
4569 | ftrace_shutdown_sysctl(); | |
4570 | } | |
4571 | ||
4572 | out: | |
e6ea44e9 | 4573 | mutex_unlock(&ftrace_lock); |
3d083395 | 4574 | return ret; |
16444a8a | 4575 | } |
f17845e5 | 4576 | |
fb52607a | 4577 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 4578 | |
597af815 | 4579 | static int ftrace_graph_active; |
4a2b8dda | 4580 | static struct notifier_block ftrace_suspend_notifier; |
e7d3737e | 4581 | |
e49dc19c SR |
4582 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
4583 | { | |
4584 | return 0; | |
4585 | } | |
4586 | ||
287b6e68 FW |
4587 | /* The callbacks that hook a function */ |
4588 | trace_func_graph_ret_t ftrace_graph_return = | |
4589 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 4590 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
4591 | |
4592 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
4593 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
4594 | { | |
4595 | int i; | |
4596 | int ret = 0; | |
4597 | unsigned long flags; | |
4598 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; | |
4599 | struct task_struct *g, *t; | |
4600 | ||
4601 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
4602 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
4603 | * sizeof(struct ftrace_ret_stack), | |
4604 | GFP_KERNEL); | |
4605 | if (!ret_stack_list[i]) { | |
4606 | start = 0; | |
4607 | end = i; | |
4608 | ret = -ENOMEM; | |
4609 | goto free; | |
4610 | } | |
4611 | } | |
4612 | ||
4613 | read_lock_irqsave(&tasklist_lock, flags); | |
4614 | do_each_thread(g, t) { | |
4615 | if (start == end) { | |
4616 | ret = -EAGAIN; | |
4617 | goto unlock; | |
4618 | } | |
4619 | ||
4620 | if (t->ret_stack == NULL) { | |
380c4b14 | 4621 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 | 4622 | atomic_set(&t->trace_overrun, 0); |
26c01624 SR |
4623 | t->curr_ret_stack = -1; |
4624 | /* Make sure the tasks see the -1 first: */ | |
4625 | smp_wmb(); | |
4626 | t->ret_stack = ret_stack_list[start++]; | |
f201ae23 FW |
4627 | } |
4628 | } while_each_thread(g, t); | |
4629 | ||
4630 | unlock: | |
4631 | read_unlock_irqrestore(&tasklist_lock, flags); | |
4632 | free: | |
4633 | for (i = start; i < end; i++) | |
4634 | kfree(ret_stack_list[i]); | |
4635 | return ret; | |
4636 | } | |
4637 | ||
8aef2d28 | 4638 | static void |
38516ab5 SR |
4639 | ftrace_graph_probe_sched_switch(void *ignore, |
4640 | struct task_struct *prev, struct task_struct *next) | |
8aef2d28 SR |
4641 | { |
4642 | unsigned long long timestamp; | |
4643 | int index; | |
4644 | ||
be6f164a SR |
4645 | /* |
4646 | * Does the user want to count the time a function was asleep. | |
4647 | * If so, do not update the time stamps. | |
4648 | */ | |
4649 | if (trace_flags & TRACE_ITER_SLEEP_TIME) | |
4650 | return; | |
4651 | ||
8aef2d28 SR |
4652 | timestamp = trace_clock_local(); |
4653 | ||
4654 | prev->ftrace_timestamp = timestamp; | |
4655 | ||
4656 | /* only process tasks that we timestamped */ | |
4657 | if (!next->ftrace_timestamp) | |
4658 | return; | |
4659 | ||
4660 | /* | |
4661 | * Update all the counters in next to make up for the | |
4662 | * time next was sleeping. | |
4663 | */ | |
4664 | timestamp -= next->ftrace_timestamp; | |
4665 | ||
4666 | for (index = next->curr_ret_stack; index >= 0; index--) | |
4667 | next->ret_stack[index].calltime += timestamp; | |
4668 | } | |
4669 | ||
f201ae23 | 4670 | /* Allocate a return stack for each task */ |
fb52607a | 4671 | static int start_graph_tracing(void) |
f201ae23 FW |
4672 | { |
4673 | struct ftrace_ret_stack **ret_stack_list; | |
5b058bcd | 4674 | int ret, cpu; |
f201ae23 FW |
4675 | |
4676 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
4677 | sizeof(struct ftrace_ret_stack *), | |
4678 | GFP_KERNEL); | |
4679 | ||
4680 | if (!ret_stack_list) | |
4681 | return -ENOMEM; | |
4682 | ||
5b058bcd | 4683 | /* The cpu_boot init_task->ret_stack will never be freed */ |
179c498a SR |
4684 | for_each_online_cpu(cpu) { |
4685 | if (!idle_task(cpu)->ret_stack) | |
868baf07 | 4686 | ftrace_graph_init_idle_task(idle_task(cpu), cpu); |
179c498a | 4687 | } |
5b058bcd | 4688 | |
f201ae23 FW |
4689 | do { |
4690 | ret = alloc_retstack_tasklist(ret_stack_list); | |
4691 | } while (ret == -EAGAIN); | |
4692 | ||
8aef2d28 | 4693 | if (!ret) { |
38516ab5 | 4694 | ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
8aef2d28 SR |
4695 | if (ret) |
4696 | pr_info("ftrace_graph: Couldn't activate tracepoint" | |
4697 | " probe to kernel_sched_switch\n"); | |
4698 | } | |
4699 | ||
f201ae23 FW |
4700 | kfree(ret_stack_list); |
4701 | return ret; | |
4702 | } | |
4703 | ||
4a2b8dda FW |
4704 | /* |
4705 | * Hibernation protection. | |
4706 | * The state of the current task is too much unstable during | |
4707 | * suspend/restore to disk. We want to protect against that. | |
4708 | */ | |
4709 | static int | |
4710 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, | |
4711 | void *unused) | |
4712 | { | |
4713 | switch (state) { | |
4714 | case PM_HIBERNATION_PREPARE: | |
4715 | pause_graph_tracing(); | |
4716 | break; | |
4717 | ||
4718 | case PM_POST_HIBERNATION: | |
4719 | unpause_graph_tracing(); | |
4720 | break; | |
4721 | } | |
4722 | return NOTIFY_DONE; | |
4723 | } | |
4724 | ||
287b6e68 FW |
4725 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
4726 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 4727 | { |
e7d3737e FW |
4728 | int ret = 0; |
4729 | ||
e6ea44e9 | 4730 | mutex_lock(&ftrace_lock); |
e7d3737e | 4731 | |
05ce5818 | 4732 | /* we currently allow only one tracer registered at a time */ |
597af815 | 4733 | if (ftrace_graph_active) { |
05ce5818 SR |
4734 | ret = -EBUSY; |
4735 | goto out; | |
4736 | } | |
4737 | ||
4a2b8dda FW |
4738 | ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call; |
4739 | register_pm_notifier(&ftrace_suspend_notifier); | |
4740 | ||
597af815 | 4741 | ftrace_graph_active++; |
fb52607a | 4742 | ret = start_graph_tracing(); |
f201ae23 | 4743 | if (ret) { |
597af815 | 4744 | ftrace_graph_active--; |
f201ae23 FW |
4745 | goto out; |
4746 | } | |
e53a6319 | 4747 | |
287b6e68 FW |
4748 | ftrace_graph_return = retfunc; |
4749 | ftrace_graph_entry = entryfunc; | |
e53a6319 | 4750 | |
a1cd6173 | 4751 | ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET); |
e7d3737e FW |
4752 | |
4753 | out: | |
e6ea44e9 | 4754 | mutex_unlock(&ftrace_lock); |
e7d3737e | 4755 | return ret; |
15e6cb36 FW |
4756 | } |
4757 | ||
fb52607a | 4758 | void unregister_ftrace_graph(void) |
15e6cb36 | 4759 | { |
e6ea44e9 | 4760 | mutex_lock(&ftrace_lock); |
e7d3737e | 4761 | |
597af815 | 4762 | if (unlikely(!ftrace_graph_active)) |
2aad1b76 SR |
4763 | goto out; |
4764 | ||
597af815 | 4765 | ftrace_graph_active--; |
287b6e68 | 4766 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; |
e49dc19c | 4767 | ftrace_graph_entry = ftrace_graph_entry_stub; |
bd69c30b | 4768 | ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET); |
4a2b8dda | 4769 | unregister_pm_notifier(&ftrace_suspend_notifier); |
38516ab5 | 4770 | unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
e7d3737e | 4771 | |
2aad1b76 | 4772 | out: |
e6ea44e9 | 4773 | mutex_unlock(&ftrace_lock); |
15e6cb36 | 4774 | } |
f201ae23 | 4775 | |
868baf07 SR |
4776 | static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack); |
4777 | ||
4778 | static void | |
4779 | graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack) | |
4780 | { | |
4781 | atomic_set(&t->tracing_graph_pause, 0); | |
4782 | atomic_set(&t->trace_overrun, 0); | |
4783 | t->ftrace_timestamp = 0; | |
25985edc | 4784 | /* make curr_ret_stack visible before we add the ret_stack */ |
868baf07 SR |
4785 | smp_wmb(); |
4786 | t->ret_stack = ret_stack; | |
4787 | } | |
4788 | ||
4789 | /* | |
4790 | * Allocate a return stack for the idle task. May be the first | |
4791 | * time through, or it may be done by CPU hotplug online. | |
4792 | */ | |
4793 | void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) | |
4794 | { | |
4795 | t->curr_ret_stack = -1; | |
4796 | /* | |
4797 | * The idle task has no parent, it either has its own | |
4798 | * stack or no stack at all. | |
4799 | */ | |
4800 | if (t->ret_stack) | |
4801 | WARN_ON(t->ret_stack != per_cpu(idle_ret_stack, cpu)); | |
4802 | ||
4803 | if (ftrace_graph_active) { | |
4804 | struct ftrace_ret_stack *ret_stack; | |
4805 | ||
4806 | ret_stack = per_cpu(idle_ret_stack, cpu); | |
4807 | if (!ret_stack) { | |
4808 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
4809 | * sizeof(struct ftrace_ret_stack), | |
4810 | GFP_KERNEL); | |
4811 | if (!ret_stack) | |
4812 | return; | |
4813 | per_cpu(idle_ret_stack, cpu) = ret_stack; | |
4814 | } | |
4815 | graph_init_task(t, ret_stack); | |
4816 | } | |
4817 | } | |
4818 | ||
f201ae23 | 4819 | /* Allocate a return stack for newly created task */ |
fb52607a | 4820 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 4821 | { |
84047e36 SR |
4822 | /* Make sure we do not use the parent ret_stack */ |
4823 | t->ret_stack = NULL; | |
ea14eb71 | 4824 | t->curr_ret_stack = -1; |
84047e36 | 4825 | |
597af815 | 4826 | if (ftrace_graph_active) { |
82310a32 SR |
4827 | struct ftrace_ret_stack *ret_stack; |
4828 | ||
4829 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
f201ae23 FW |
4830 | * sizeof(struct ftrace_ret_stack), |
4831 | GFP_KERNEL); | |
82310a32 | 4832 | if (!ret_stack) |
f201ae23 | 4833 | return; |
868baf07 | 4834 | graph_init_task(t, ret_stack); |
84047e36 | 4835 | } |
f201ae23 FW |
4836 | } |
4837 | ||
fb52607a | 4838 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 4839 | { |
eae849ca FW |
4840 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
4841 | ||
f201ae23 | 4842 | t->ret_stack = NULL; |
eae849ca FW |
4843 | /* NULL must become visible to IRQs before we free it: */ |
4844 | barrier(); | |
4845 | ||
4846 | kfree(ret_stack); | |
f201ae23 | 4847 | } |
14a866c5 SR |
4848 | |
4849 | void ftrace_graph_stop(void) | |
4850 | { | |
4851 | ftrace_stop(); | |
4852 | } | |
15e6cb36 | 4853 | #endif |