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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 | ||
f04f24fb MH |
67 | #ifdef CONFIG_DYNAMIC_FTRACE |
68 | #define INIT_REGEX_LOCK(opsname) \ | |
69 | .regex_lock = __MUTEX_INITIALIZER(opsname.regex_lock), | |
70 | #else | |
71 | #define INIT_REGEX_LOCK(opsname) | |
72 | #endif | |
73 | ||
2f5f6ad9 SR |
74 | static struct ftrace_ops ftrace_list_end __read_mostly = { |
75 | .func = ftrace_stub, | |
395b97a3 | 76 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_STUB, |
2f5f6ad9 SR |
77 | }; |
78 | ||
4eebcc81 SR |
79 | /* ftrace_enabled is a method to turn ftrace on or off */ |
80 | int ftrace_enabled __read_mostly; | |
d61f82d0 | 81 | static int last_ftrace_enabled; |
b0fc494f | 82 | |
60a7ecf4 | 83 | /* Quick disabling of function tracer. */ |
2f5f6ad9 SR |
84 | int function_trace_stop __read_mostly; |
85 | ||
86 | /* Current function tracing op */ | |
87 | struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end; | |
60a7ecf4 | 88 | |
756d17ee | 89 | /* List for set_ftrace_pid's pids. */ |
90 | LIST_HEAD(ftrace_pids); | |
91 | struct ftrace_pid { | |
92 | struct list_head list; | |
93 | struct pid *pid; | |
94 | }; | |
95 | ||
4eebcc81 SR |
96 | /* |
97 | * ftrace_disabled is set when an anomaly is discovered. | |
98 | * ftrace_disabled is much stronger than ftrace_enabled. | |
99 | */ | |
100 | static int ftrace_disabled __read_mostly; | |
101 | ||
52baf119 | 102 | static DEFINE_MUTEX(ftrace_lock); |
b0fc494f | 103 | |
b848914c | 104 | static struct ftrace_ops *ftrace_global_list __read_mostly = &ftrace_list_end; |
e248491a | 105 | static struct ftrace_ops *ftrace_control_list __read_mostly = &ftrace_list_end; |
b848914c | 106 | static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end; |
16444a8a | 107 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; |
df4fc315 | 108 | ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub; |
2b499381 | 109 | static struct ftrace_ops global_ops; |
e248491a | 110 | static struct ftrace_ops control_ops; |
16444a8a | 111 | |
2f5f6ad9 SR |
112 | #if ARCH_SUPPORTS_FTRACE_OPS |
113 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 114 | struct ftrace_ops *op, struct pt_regs *regs); |
2f5f6ad9 SR |
115 | #else |
116 | /* See comment below, where ftrace_ops_list_func is defined */ | |
117 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip); | |
118 | #define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops) | |
119 | #endif | |
b848914c | 120 | |
0a016409 SR |
121 | /* |
122 | * Traverse the ftrace_global_list, invoking all entries. The reason that we | |
123 | * can use rcu_dereference_raw() is that elements removed from this list | |
124 | * are simply leaked, so there is no need to interact with a grace-period | |
125 | * mechanism. The rcu_dereference_raw() calls are needed to handle | |
126 | * concurrent insertions into the ftrace_global_list. | |
127 | * | |
128 | * Silly Alpha and silly pointer-speculation compiler optimizations! | |
129 | */ | |
130 | #define do_for_each_ftrace_op(op, list) \ | |
131 | op = rcu_dereference_raw(list); \ | |
132 | do | |
133 | ||
134 | /* | |
135 | * Optimized for just a single item in the list (as that is the normal case). | |
136 | */ | |
137 | #define while_for_each_ftrace_op(op) \ | |
138 | while (likely(op = rcu_dereference_raw((op)->next)) && \ | |
139 | unlikely((op) != &ftrace_list_end)) | |
140 | ||
f04f24fb MH |
141 | static inline void ftrace_ops_init(struct ftrace_ops *ops) |
142 | { | |
143 | #ifdef CONFIG_DYNAMIC_FTRACE | |
144 | if (!(ops->flags & FTRACE_OPS_FL_INITIALIZED)) { | |
145 | mutex_init(&ops->regex_lock); | |
146 | ops->flags |= FTRACE_OPS_FL_INITIALIZED; | |
147 | } | |
148 | #endif | |
149 | } | |
150 | ||
ea701f11 SR |
151 | /** |
152 | * ftrace_nr_registered_ops - return number of ops registered | |
153 | * | |
154 | * Returns the number of ftrace_ops registered and tracing functions | |
155 | */ | |
156 | int ftrace_nr_registered_ops(void) | |
157 | { | |
158 | struct ftrace_ops *ops; | |
159 | int cnt = 0; | |
160 | ||
161 | mutex_lock(&ftrace_lock); | |
162 | ||
163 | for (ops = ftrace_ops_list; | |
164 | ops != &ftrace_list_end; ops = ops->next) | |
165 | cnt++; | |
166 | ||
167 | mutex_unlock(&ftrace_lock); | |
168 | ||
169 | return cnt; | |
170 | } | |
171 | ||
2f5f6ad9 SR |
172 | static void |
173 | ftrace_global_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 174 | struct ftrace_ops *op, struct pt_regs *regs) |
16444a8a | 175 | { |
c29f122c SR |
176 | int bit; |
177 | ||
edc15caf SR |
178 | bit = trace_test_and_set_recursion(TRACE_GLOBAL_START, TRACE_GLOBAL_MAX); |
179 | if (bit < 0) | |
b1cff0ad | 180 | return; |
16444a8a | 181 | |
0a016409 | 182 | do_for_each_ftrace_op(op, ftrace_global_list) { |
a1e2e31d | 183 | op->func(ip, parent_ip, op, regs); |
0a016409 | 184 | } while_for_each_ftrace_op(op); |
edc15caf SR |
185 | |
186 | trace_clear_recursion(bit); | |
16444a8a ACM |
187 | } |
188 | ||
2f5f6ad9 | 189 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 190 | struct ftrace_ops *op, struct pt_regs *regs) |
df4fc315 | 191 | { |
0ef8cde5 | 192 | if (!test_tsk_trace_trace(current)) |
df4fc315 SR |
193 | return; |
194 | ||
a1e2e31d | 195 | ftrace_pid_function(ip, parent_ip, op, regs); |
df4fc315 SR |
196 | } |
197 | ||
198 | static void set_ftrace_pid_function(ftrace_func_t func) | |
199 | { | |
200 | /* do not set ftrace_pid_function to itself! */ | |
201 | if (func != ftrace_pid_func) | |
202 | ftrace_pid_function = func; | |
203 | } | |
204 | ||
16444a8a | 205 | /** |
3d083395 | 206 | * clear_ftrace_function - reset the ftrace function |
16444a8a | 207 | * |
3d083395 SR |
208 | * This NULLs the ftrace function and in essence stops |
209 | * tracing. There may be lag | |
16444a8a | 210 | */ |
3d083395 | 211 | void clear_ftrace_function(void) |
16444a8a | 212 | { |
3d083395 | 213 | ftrace_trace_function = ftrace_stub; |
df4fc315 | 214 | ftrace_pid_function = ftrace_stub; |
3d083395 SR |
215 | } |
216 | ||
e248491a JO |
217 | static void control_ops_disable_all(struct ftrace_ops *ops) |
218 | { | |
219 | int cpu; | |
220 | ||
221 | for_each_possible_cpu(cpu) | |
222 | *per_cpu_ptr(ops->disabled, cpu) = 1; | |
223 | } | |
224 | ||
225 | static int control_ops_alloc(struct ftrace_ops *ops) | |
226 | { | |
227 | int __percpu *disabled; | |
228 | ||
229 | disabled = alloc_percpu(int); | |
230 | if (!disabled) | |
231 | return -ENOMEM; | |
232 | ||
233 | ops->disabled = disabled; | |
234 | control_ops_disable_all(ops); | |
235 | return 0; | |
236 | } | |
237 | ||
238 | static void control_ops_free(struct ftrace_ops *ops) | |
239 | { | |
240 | free_percpu(ops->disabled); | |
241 | } | |
242 | ||
2b499381 | 243 | static void update_global_ops(void) |
491d0dcf SR |
244 | { |
245 | ftrace_func_t func; | |
246 | ||
247 | /* | |
248 | * If there's only one function registered, then call that | |
249 | * function directly. Otherwise, we need to iterate over the | |
250 | * registered callers. | |
251 | */ | |
b848914c | 252 | if (ftrace_global_list == &ftrace_list_end || |
63503794 | 253 | ftrace_global_list->next == &ftrace_list_end) { |
b848914c | 254 | func = ftrace_global_list->func; |
63503794 SR |
255 | /* |
256 | * As we are calling the function directly. | |
257 | * If it does not have recursion protection, | |
258 | * the function_trace_op needs to be updated | |
259 | * accordingly. | |
260 | */ | |
261 | if (ftrace_global_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) | |
262 | global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE; | |
263 | else | |
264 | global_ops.flags &= ~FTRACE_OPS_FL_RECURSION_SAFE; | |
265 | } else { | |
b848914c | 266 | func = ftrace_global_list_func; |
63503794 SR |
267 | /* The list has its own recursion protection. */ |
268 | global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE; | |
269 | } | |
270 | ||
491d0dcf SR |
271 | |
272 | /* If we filter on pids, update to use the pid function */ | |
273 | if (!list_empty(&ftrace_pids)) { | |
274 | set_ftrace_pid_function(func); | |
275 | func = ftrace_pid_func; | |
276 | } | |
2b499381 SR |
277 | |
278 | global_ops.func = func; | |
279 | } | |
280 | ||
281 | static void update_ftrace_function(void) | |
282 | { | |
283 | ftrace_func_t func; | |
284 | ||
285 | update_global_ops(); | |
286 | ||
cdbe61bf SR |
287 | /* |
288 | * If we are at the end of the list and this ops is | |
4740974a SR |
289 | * recursion safe and not dynamic and the arch supports passing ops, |
290 | * then have the mcount trampoline call the function directly. | |
cdbe61bf | 291 | */ |
b848914c | 292 | if (ftrace_ops_list == &ftrace_list_end || |
cdbe61bf | 293 | (ftrace_ops_list->next == &ftrace_list_end && |
2f5f6ad9 | 294 | !(ftrace_ops_list->flags & FTRACE_OPS_FL_DYNAMIC) && |
4740974a | 295 | (ftrace_ops_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) && |
ccf3672d | 296 | !FTRACE_FORCE_LIST_FUNC)) { |
2f5f6ad9 SR |
297 | /* Set the ftrace_ops that the arch callback uses */ |
298 | if (ftrace_ops_list == &global_ops) | |
299 | function_trace_op = ftrace_global_list; | |
300 | else | |
301 | function_trace_op = ftrace_ops_list; | |
b848914c | 302 | func = ftrace_ops_list->func; |
2f5f6ad9 SR |
303 | } else { |
304 | /* Just use the default ftrace_ops */ | |
305 | function_trace_op = &ftrace_list_end; | |
b848914c | 306 | func = ftrace_ops_list_func; |
2f5f6ad9 | 307 | } |
2b499381 | 308 | |
491d0dcf | 309 | ftrace_trace_function = func; |
491d0dcf SR |
310 | } |
311 | ||
2b499381 | 312 | static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
3d083395 | 313 | { |
2b499381 | 314 | ops->next = *list; |
16444a8a | 315 | /* |
b848914c | 316 | * We are entering ops into the list but another |
16444a8a ACM |
317 | * CPU might be walking that list. We need to make sure |
318 | * the ops->next pointer is valid before another CPU sees | |
b848914c | 319 | * the ops pointer included into the list. |
16444a8a | 320 | */ |
2b499381 | 321 | rcu_assign_pointer(*list, ops); |
16444a8a ACM |
322 | } |
323 | ||
2b499381 | 324 | static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
16444a8a | 325 | { |
16444a8a | 326 | struct ftrace_ops **p; |
16444a8a ACM |
327 | |
328 | /* | |
3d083395 SR |
329 | * If we are removing the last function, then simply point |
330 | * to the ftrace_stub. | |
16444a8a | 331 | */ |
2b499381 SR |
332 | if (*list == ops && ops->next == &ftrace_list_end) { |
333 | *list = &ftrace_list_end; | |
e6ea44e9 | 334 | return 0; |
16444a8a ACM |
335 | } |
336 | ||
2b499381 | 337 | for (p = list; *p != &ftrace_list_end; p = &(*p)->next) |
16444a8a ACM |
338 | if (*p == ops) |
339 | break; | |
340 | ||
e6ea44e9 SR |
341 | if (*p != ops) |
342 | return -1; | |
16444a8a ACM |
343 | |
344 | *p = (*p)->next; | |
2b499381 SR |
345 | return 0; |
346 | } | |
16444a8a | 347 | |
e248491a JO |
348 | static void add_ftrace_list_ops(struct ftrace_ops **list, |
349 | struct ftrace_ops *main_ops, | |
350 | struct ftrace_ops *ops) | |
351 | { | |
352 | int first = *list == &ftrace_list_end; | |
353 | add_ftrace_ops(list, ops); | |
354 | if (first) | |
355 | add_ftrace_ops(&ftrace_ops_list, main_ops); | |
356 | } | |
357 | ||
358 | static int remove_ftrace_list_ops(struct ftrace_ops **list, | |
359 | struct ftrace_ops *main_ops, | |
360 | struct ftrace_ops *ops) | |
361 | { | |
362 | int ret = remove_ftrace_ops(list, ops); | |
363 | if (!ret && *list == &ftrace_list_end) | |
364 | ret = remove_ftrace_ops(&ftrace_ops_list, main_ops); | |
365 | return ret; | |
366 | } | |
367 | ||
2b499381 SR |
368 | static int __register_ftrace_function(struct ftrace_ops *ops) |
369 | { | |
8d240dd8 | 370 | if (unlikely(ftrace_disabled)) |
2b499381 SR |
371 | return -ENODEV; |
372 | ||
373 | if (FTRACE_WARN_ON(ops == &global_ops)) | |
374 | return -EINVAL; | |
375 | ||
b848914c SR |
376 | if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED)) |
377 | return -EBUSY; | |
378 | ||
e248491a JO |
379 | /* We don't support both control and global flags set. */ |
380 | if ((ops->flags & FL_GLOBAL_CONTROL_MASK) == FL_GLOBAL_CONTROL_MASK) | |
381 | return -EINVAL; | |
382 | ||
06aeaaea | 383 | #ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
08f6fba5 SR |
384 | /* |
385 | * If the ftrace_ops specifies SAVE_REGS, then it only can be used | |
386 | * if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set. | |
387 | * Setting SAVE_REGS_IF_SUPPORTED makes SAVE_REGS irrelevant. | |
388 | */ | |
389 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS && | |
390 | !(ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)) | |
391 | return -EINVAL; | |
392 | ||
393 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED) | |
394 | ops->flags |= FTRACE_OPS_FL_SAVE_REGS; | |
395 | #endif | |
396 | ||
cdbe61bf SR |
397 | if (!core_kernel_data((unsigned long)ops)) |
398 | ops->flags |= FTRACE_OPS_FL_DYNAMIC; | |
399 | ||
b848914c | 400 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
e248491a | 401 | add_ftrace_list_ops(&ftrace_global_list, &global_ops, ops); |
b848914c | 402 | ops->flags |= FTRACE_OPS_FL_ENABLED; |
e248491a JO |
403 | } else if (ops->flags & FTRACE_OPS_FL_CONTROL) { |
404 | if (control_ops_alloc(ops)) | |
405 | return -ENOMEM; | |
406 | add_ftrace_list_ops(&ftrace_control_list, &control_ops, ops); | |
b848914c SR |
407 | } else |
408 | add_ftrace_ops(&ftrace_ops_list, ops); | |
409 | ||
2b499381 SR |
410 | if (ftrace_enabled) |
411 | update_ftrace_function(); | |
412 | ||
413 | return 0; | |
414 | } | |
415 | ||
416 | static int __unregister_ftrace_function(struct ftrace_ops *ops) | |
417 | { | |
418 | int ret; | |
419 | ||
420 | if (ftrace_disabled) | |
421 | return -ENODEV; | |
422 | ||
b848914c SR |
423 | if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) |
424 | return -EBUSY; | |
425 | ||
2b499381 SR |
426 | if (FTRACE_WARN_ON(ops == &global_ops)) |
427 | return -EINVAL; | |
428 | ||
b848914c | 429 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
e248491a JO |
430 | ret = remove_ftrace_list_ops(&ftrace_global_list, |
431 | &global_ops, ops); | |
b848914c SR |
432 | if (!ret) |
433 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; | |
e248491a JO |
434 | } else if (ops->flags & FTRACE_OPS_FL_CONTROL) { |
435 | ret = remove_ftrace_list_ops(&ftrace_control_list, | |
436 | &control_ops, ops); | |
437 | if (!ret) { | |
438 | /* | |
439 | * The ftrace_ops is now removed from the list, | |
440 | * so there'll be no new users. We must ensure | |
441 | * all current users are done before we free | |
442 | * the control data. | |
443 | */ | |
444 | synchronize_sched(); | |
445 | control_ops_free(ops); | |
446 | } | |
b848914c SR |
447 | } else |
448 | ret = remove_ftrace_ops(&ftrace_ops_list, ops); | |
449 | ||
2b499381 SR |
450 | if (ret < 0) |
451 | return ret; | |
b848914c | 452 | |
491d0dcf SR |
453 | if (ftrace_enabled) |
454 | update_ftrace_function(); | |
16444a8a | 455 | |
cdbe61bf SR |
456 | /* |
457 | * Dynamic ops may be freed, we must make sure that all | |
458 | * callers are done before leaving this function. | |
459 | */ | |
460 | if (ops->flags & FTRACE_OPS_FL_DYNAMIC) | |
461 | synchronize_sched(); | |
462 | ||
e6ea44e9 | 463 | return 0; |
3d083395 SR |
464 | } |
465 | ||
df4fc315 SR |
466 | static void ftrace_update_pid_func(void) |
467 | { | |
491d0dcf | 468 | /* Only do something if we are tracing something */ |
df4fc315 | 469 | if (ftrace_trace_function == ftrace_stub) |
10dd3ebe | 470 | return; |
df4fc315 | 471 | |
491d0dcf | 472 | update_ftrace_function(); |
df4fc315 SR |
473 | } |
474 | ||
493762fc SR |
475 | #ifdef CONFIG_FUNCTION_PROFILER |
476 | struct ftrace_profile { | |
477 | struct hlist_node node; | |
478 | unsigned long ip; | |
479 | unsigned long counter; | |
0706f1c4 SR |
480 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
481 | unsigned long long time; | |
e330b3bc | 482 | unsigned long long time_squared; |
0706f1c4 | 483 | #endif |
8fc0c701 SR |
484 | }; |
485 | ||
493762fc SR |
486 | struct ftrace_profile_page { |
487 | struct ftrace_profile_page *next; | |
488 | unsigned long index; | |
489 | struct ftrace_profile records[]; | |
d61f82d0 SR |
490 | }; |
491 | ||
cafb168a SR |
492 | struct ftrace_profile_stat { |
493 | atomic_t disabled; | |
494 | struct hlist_head *hash; | |
495 | struct ftrace_profile_page *pages; | |
496 | struct ftrace_profile_page *start; | |
497 | struct tracer_stat stat; | |
498 | }; | |
499 | ||
493762fc SR |
500 | #define PROFILE_RECORDS_SIZE \ |
501 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | |
5072c59f | 502 | |
493762fc SR |
503 | #define PROFILES_PER_PAGE \ |
504 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | |
3d083395 | 505 | |
fb9fb015 SR |
506 | static int ftrace_profile_enabled __read_mostly; |
507 | ||
508 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ | |
bac429f0 SR |
509 | static DEFINE_MUTEX(ftrace_profile_lock); |
510 | ||
cafb168a | 511 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); |
493762fc | 512 | |
20079ebe NK |
513 | #define FTRACE_PROFILE_HASH_BITS 10 |
514 | #define FTRACE_PROFILE_HASH_SIZE (1 << FTRACE_PROFILE_HASH_BITS) | |
493762fc | 515 | |
bac429f0 SR |
516 | static void * |
517 | function_stat_next(void *v, int idx) | |
518 | { | |
493762fc SR |
519 | struct ftrace_profile *rec = v; |
520 | struct ftrace_profile_page *pg; | |
bac429f0 | 521 | |
493762fc | 522 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
bac429f0 SR |
523 | |
524 | again: | |
0296e425 LZ |
525 | if (idx != 0) |
526 | rec++; | |
527 | ||
bac429f0 SR |
528 | if ((void *)rec >= (void *)&pg->records[pg->index]) { |
529 | pg = pg->next; | |
530 | if (!pg) | |
531 | return NULL; | |
532 | rec = &pg->records[0]; | |
493762fc SR |
533 | if (!rec->counter) |
534 | goto again; | |
bac429f0 SR |
535 | } |
536 | ||
bac429f0 SR |
537 | return rec; |
538 | } | |
539 | ||
540 | static void *function_stat_start(struct tracer_stat *trace) | |
541 | { | |
cafb168a SR |
542 | struct ftrace_profile_stat *stat = |
543 | container_of(trace, struct ftrace_profile_stat, stat); | |
544 | ||
545 | if (!stat || !stat->start) | |
546 | return NULL; | |
547 | ||
548 | return function_stat_next(&stat->start->records[0], 0); | |
bac429f0 SR |
549 | } |
550 | ||
0706f1c4 SR |
551 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
552 | /* function graph compares on total time */ | |
553 | static int function_stat_cmp(void *p1, void *p2) | |
554 | { | |
555 | struct ftrace_profile *a = p1; | |
556 | struct ftrace_profile *b = p2; | |
557 | ||
558 | if (a->time < b->time) | |
559 | return -1; | |
560 | if (a->time > b->time) | |
561 | return 1; | |
562 | else | |
563 | return 0; | |
564 | } | |
565 | #else | |
566 | /* not function graph compares against hits */ | |
bac429f0 SR |
567 | static int function_stat_cmp(void *p1, void *p2) |
568 | { | |
493762fc SR |
569 | struct ftrace_profile *a = p1; |
570 | struct ftrace_profile *b = p2; | |
bac429f0 SR |
571 | |
572 | if (a->counter < b->counter) | |
573 | return -1; | |
574 | if (a->counter > b->counter) | |
575 | return 1; | |
576 | else | |
577 | return 0; | |
578 | } | |
0706f1c4 | 579 | #endif |
bac429f0 SR |
580 | |
581 | static int function_stat_headers(struct seq_file *m) | |
582 | { | |
0706f1c4 | 583 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b | 584 | seq_printf(m, " Function " |
e330b3bc | 585 | "Hit Time Avg s^2\n" |
34886c8b | 586 | " -------- " |
e330b3bc | 587 | "--- ---- --- ---\n"); |
0706f1c4 | 588 | #else |
bac429f0 SR |
589 | seq_printf(m, " Function Hit\n" |
590 | " -------- ---\n"); | |
0706f1c4 | 591 | #endif |
bac429f0 SR |
592 | return 0; |
593 | } | |
594 | ||
595 | static int function_stat_show(struct seq_file *m, void *v) | |
596 | { | |
493762fc | 597 | struct ftrace_profile *rec = v; |
bac429f0 | 598 | char str[KSYM_SYMBOL_LEN]; |
3aaba20f | 599 | int ret = 0; |
0706f1c4 | 600 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b SR |
601 | static struct trace_seq s; |
602 | unsigned long long avg; | |
e330b3bc | 603 | unsigned long long stddev; |
0706f1c4 | 604 | #endif |
3aaba20f LZ |
605 | mutex_lock(&ftrace_profile_lock); |
606 | ||
607 | /* we raced with function_profile_reset() */ | |
608 | if (unlikely(rec->counter == 0)) { | |
609 | ret = -EBUSY; | |
610 | goto out; | |
611 | } | |
bac429f0 SR |
612 | |
613 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
0706f1c4 SR |
614 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); |
615 | ||
616 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
617 | seq_printf(m, " "); | |
34886c8b SR |
618 | avg = rec->time; |
619 | do_div(avg, rec->counter); | |
620 | ||
e330b3bc CD |
621 | /* Sample standard deviation (s^2) */ |
622 | if (rec->counter <= 1) | |
623 | stddev = 0; | |
624 | else { | |
625 | stddev = rec->time_squared - rec->counter * avg * avg; | |
626 | /* | |
627 | * Divide only 1000 for ns^2 -> us^2 conversion. | |
628 | * trace_print_graph_duration will divide 1000 again. | |
629 | */ | |
630 | do_div(stddev, (rec->counter - 1) * 1000); | |
631 | } | |
632 | ||
34886c8b SR |
633 | trace_seq_init(&s); |
634 | trace_print_graph_duration(rec->time, &s); | |
635 | trace_seq_puts(&s, " "); | |
636 | trace_print_graph_duration(avg, &s); | |
e330b3bc CD |
637 | trace_seq_puts(&s, " "); |
638 | trace_print_graph_duration(stddev, &s); | |
0706f1c4 | 639 | trace_print_seq(m, &s); |
0706f1c4 SR |
640 | #endif |
641 | seq_putc(m, '\n'); | |
3aaba20f LZ |
642 | out: |
643 | mutex_unlock(&ftrace_profile_lock); | |
bac429f0 | 644 | |
3aaba20f | 645 | return ret; |
bac429f0 SR |
646 | } |
647 | ||
cafb168a | 648 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) |
bac429f0 | 649 | { |
493762fc | 650 | struct ftrace_profile_page *pg; |
bac429f0 | 651 | |
cafb168a | 652 | pg = stat->pages = stat->start; |
bac429f0 | 653 | |
493762fc SR |
654 | while (pg) { |
655 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | |
656 | pg->index = 0; | |
657 | pg = pg->next; | |
bac429f0 SR |
658 | } |
659 | ||
cafb168a | 660 | memset(stat->hash, 0, |
493762fc SR |
661 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); |
662 | } | |
bac429f0 | 663 | |
cafb168a | 664 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) |
493762fc SR |
665 | { |
666 | struct ftrace_profile_page *pg; | |
318e0a73 SR |
667 | int functions; |
668 | int pages; | |
493762fc | 669 | int i; |
bac429f0 | 670 | |
493762fc | 671 | /* If we already allocated, do nothing */ |
cafb168a | 672 | if (stat->pages) |
493762fc | 673 | return 0; |
bac429f0 | 674 | |
cafb168a SR |
675 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); |
676 | if (!stat->pages) | |
493762fc | 677 | return -ENOMEM; |
bac429f0 | 678 | |
318e0a73 SR |
679 | #ifdef CONFIG_DYNAMIC_FTRACE |
680 | functions = ftrace_update_tot_cnt; | |
681 | #else | |
682 | /* | |
683 | * We do not know the number of functions that exist because | |
684 | * dynamic tracing is what counts them. With past experience | |
685 | * we have around 20K functions. That should be more than enough. | |
686 | * It is highly unlikely we will execute every function in | |
687 | * the kernel. | |
688 | */ | |
689 | functions = 20000; | |
690 | #endif | |
691 | ||
cafb168a | 692 | pg = stat->start = stat->pages; |
bac429f0 | 693 | |
318e0a73 SR |
694 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); |
695 | ||
39e30cd1 | 696 | for (i = 1; i < pages; i++) { |
493762fc | 697 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
493762fc | 698 | if (!pg->next) |
318e0a73 | 699 | goto out_free; |
493762fc SR |
700 | pg = pg->next; |
701 | } | |
702 | ||
703 | return 0; | |
318e0a73 SR |
704 | |
705 | out_free: | |
706 | pg = stat->start; | |
707 | while (pg) { | |
708 | unsigned long tmp = (unsigned long)pg; | |
709 | ||
710 | pg = pg->next; | |
711 | free_page(tmp); | |
712 | } | |
713 | ||
318e0a73 SR |
714 | stat->pages = NULL; |
715 | stat->start = NULL; | |
716 | ||
717 | return -ENOMEM; | |
bac429f0 SR |
718 | } |
719 | ||
cafb168a | 720 | static int ftrace_profile_init_cpu(int cpu) |
bac429f0 | 721 | { |
cafb168a | 722 | struct ftrace_profile_stat *stat; |
493762fc | 723 | int size; |
bac429f0 | 724 | |
cafb168a SR |
725 | stat = &per_cpu(ftrace_profile_stats, cpu); |
726 | ||
727 | if (stat->hash) { | |
493762fc | 728 | /* If the profile is already created, simply reset it */ |
cafb168a | 729 | ftrace_profile_reset(stat); |
493762fc SR |
730 | return 0; |
731 | } | |
bac429f0 | 732 | |
493762fc SR |
733 | /* |
734 | * We are profiling all functions, but usually only a few thousand | |
735 | * functions are hit. We'll make a hash of 1024 items. | |
736 | */ | |
737 | size = FTRACE_PROFILE_HASH_SIZE; | |
bac429f0 | 738 | |
cafb168a | 739 | stat->hash = kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL); |
493762fc | 740 | |
cafb168a | 741 | if (!stat->hash) |
493762fc SR |
742 | return -ENOMEM; |
743 | ||
318e0a73 | 744 | /* Preallocate the function profiling pages */ |
cafb168a SR |
745 | if (ftrace_profile_pages_init(stat) < 0) { |
746 | kfree(stat->hash); | |
747 | stat->hash = NULL; | |
493762fc SR |
748 | return -ENOMEM; |
749 | } | |
750 | ||
751 | return 0; | |
bac429f0 SR |
752 | } |
753 | ||
cafb168a SR |
754 | static int ftrace_profile_init(void) |
755 | { | |
756 | int cpu; | |
757 | int ret = 0; | |
758 | ||
759 | for_each_online_cpu(cpu) { | |
760 | ret = ftrace_profile_init_cpu(cpu); | |
761 | if (ret) | |
762 | break; | |
763 | } | |
764 | ||
765 | return ret; | |
766 | } | |
767 | ||
493762fc | 768 | /* interrupts must be disabled */ |
cafb168a SR |
769 | static struct ftrace_profile * |
770 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) | |
bac429f0 | 771 | { |
493762fc | 772 | struct ftrace_profile *rec; |
bac429f0 | 773 | struct hlist_head *hhd; |
bac429f0 SR |
774 | unsigned long key; |
775 | ||
20079ebe | 776 | key = hash_long(ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 777 | hhd = &stat->hash[key]; |
bac429f0 SR |
778 | |
779 | if (hlist_empty(hhd)) | |
780 | return NULL; | |
781 | ||
b67bfe0d | 782 | hlist_for_each_entry_rcu(rec, hhd, node) { |
bac429f0 | 783 | if (rec->ip == ip) |
493762fc SR |
784 | return rec; |
785 | } | |
786 | ||
787 | return NULL; | |
788 | } | |
789 | ||
cafb168a SR |
790 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, |
791 | struct ftrace_profile *rec) | |
493762fc SR |
792 | { |
793 | unsigned long key; | |
794 | ||
20079ebe | 795 | key = hash_long(rec->ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 796 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); |
493762fc SR |
797 | } |
798 | ||
318e0a73 SR |
799 | /* |
800 | * The memory is already allocated, this simply finds a new record to use. | |
801 | */ | |
493762fc | 802 | static struct ftrace_profile * |
318e0a73 | 803 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) |
493762fc SR |
804 | { |
805 | struct ftrace_profile *rec = NULL; | |
806 | ||
318e0a73 | 807 | /* prevent recursion (from NMIs) */ |
cafb168a | 808 | if (atomic_inc_return(&stat->disabled) != 1) |
493762fc SR |
809 | goto out; |
810 | ||
493762fc | 811 | /* |
318e0a73 SR |
812 | * Try to find the function again since an NMI |
813 | * could have added it | |
493762fc | 814 | */ |
cafb168a | 815 | rec = ftrace_find_profiled_func(stat, ip); |
493762fc | 816 | if (rec) |
cafb168a | 817 | goto out; |
493762fc | 818 | |
cafb168a SR |
819 | if (stat->pages->index == PROFILES_PER_PAGE) { |
820 | if (!stat->pages->next) | |
821 | goto out; | |
822 | stat->pages = stat->pages->next; | |
bac429f0 | 823 | } |
493762fc | 824 | |
cafb168a | 825 | rec = &stat->pages->records[stat->pages->index++]; |
493762fc | 826 | rec->ip = ip; |
cafb168a | 827 | ftrace_add_profile(stat, rec); |
493762fc | 828 | |
bac429f0 | 829 | out: |
cafb168a | 830 | atomic_dec(&stat->disabled); |
bac429f0 SR |
831 | |
832 | return rec; | |
833 | } | |
834 | ||
835 | static void | |
2f5f6ad9 | 836 | function_profile_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 837 | struct ftrace_ops *ops, struct pt_regs *regs) |
bac429f0 | 838 | { |
cafb168a | 839 | struct ftrace_profile_stat *stat; |
493762fc | 840 | struct ftrace_profile *rec; |
bac429f0 SR |
841 | unsigned long flags; |
842 | ||
843 | if (!ftrace_profile_enabled) | |
844 | return; | |
845 | ||
846 | local_irq_save(flags); | |
cafb168a SR |
847 | |
848 | stat = &__get_cpu_var(ftrace_profile_stats); | |
0f6ce3de | 849 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
850 | goto out; |
851 | ||
852 | rec = ftrace_find_profiled_func(stat, ip); | |
493762fc | 853 | if (!rec) { |
318e0a73 | 854 | rec = ftrace_profile_alloc(stat, ip); |
493762fc SR |
855 | if (!rec) |
856 | goto out; | |
857 | } | |
bac429f0 SR |
858 | |
859 | rec->counter++; | |
860 | out: | |
861 | local_irq_restore(flags); | |
862 | } | |
863 | ||
0706f1c4 SR |
864 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
865 | static int profile_graph_entry(struct ftrace_graph_ent *trace) | |
866 | { | |
a1e2e31d | 867 | function_profile_call(trace->func, 0, NULL, NULL); |
0706f1c4 SR |
868 | return 1; |
869 | } | |
870 | ||
871 | static void profile_graph_return(struct ftrace_graph_ret *trace) | |
872 | { | |
cafb168a | 873 | struct ftrace_profile_stat *stat; |
a2a16d6a | 874 | unsigned long long calltime; |
0706f1c4 | 875 | struct ftrace_profile *rec; |
cafb168a | 876 | unsigned long flags; |
0706f1c4 SR |
877 | |
878 | local_irq_save(flags); | |
cafb168a | 879 | stat = &__get_cpu_var(ftrace_profile_stats); |
0f6ce3de | 880 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
881 | goto out; |
882 | ||
37e44bc5 SR |
883 | /* If the calltime was zero'd ignore it */ |
884 | if (!trace->calltime) | |
885 | goto out; | |
886 | ||
a2a16d6a SR |
887 | calltime = trace->rettime - trace->calltime; |
888 | ||
889 | if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) { | |
890 | int index; | |
891 | ||
892 | index = trace->depth; | |
893 | ||
894 | /* Append this call time to the parent time to subtract */ | |
895 | if (index) | |
896 | current->ret_stack[index - 1].subtime += calltime; | |
897 | ||
898 | if (current->ret_stack[index].subtime < calltime) | |
899 | calltime -= current->ret_stack[index].subtime; | |
900 | else | |
901 | calltime = 0; | |
902 | } | |
903 | ||
cafb168a | 904 | rec = ftrace_find_profiled_func(stat, trace->func); |
e330b3bc | 905 | if (rec) { |
a2a16d6a | 906 | rec->time += calltime; |
e330b3bc CD |
907 | rec->time_squared += calltime * calltime; |
908 | } | |
a2a16d6a | 909 | |
cafb168a | 910 | out: |
0706f1c4 SR |
911 | local_irq_restore(flags); |
912 | } | |
913 | ||
914 | static int register_ftrace_profiler(void) | |
915 | { | |
916 | return register_ftrace_graph(&profile_graph_return, | |
917 | &profile_graph_entry); | |
918 | } | |
919 | ||
920 | static void unregister_ftrace_profiler(void) | |
921 | { | |
922 | unregister_ftrace_graph(); | |
923 | } | |
924 | #else | |
bd38c0e6 | 925 | static struct ftrace_ops ftrace_profile_ops __read_mostly = { |
fb9fb015 | 926 | .func = function_profile_call, |
f04f24fb MH |
927 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, |
928 | INIT_REGEX_LOCK(ftrace_profile_ops) | |
bac429f0 SR |
929 | }; |
930 | ||
0706f1c4 SR |
931 | static int register_ftrace_profiler(void) |
932 | { | |
933 | return register_ftrace_function(&ftrace_profile_ops); | |
934 | } | |
935 | ||
936 | static void unregister_ftrace_profiler(void) | |
937 | { | |
938 | unregister_ftrace_function(&ftrace_profile_ops); | |
939 | } | |
940 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
941 | ||
bac429f0 SR |
942 | static ssize_t |
943 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | |
944 | size_t cnt, loff_t *ppos) | |
945 | { | |
946 | unsigned long val; | |
bac429f0 SR |
947 | int ret; |
948 | ||
22fe9b54 PH |
949 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
950 | if (ret) | |
bac429f0 SR |
951 | return ret; |
952 | ||
953 | val = !!val; | |
954 | ||
955 | mutex_lock(&ftrace_profile_lock); | |
956 | if (ftrace_profile_enabled ^ val) { | |
957 | if (val) { | |
493762fc SR |
958 | ret = ftrace_profile_init(); |
959 | if (ret < 0) { | |
960 | cnt = ret; | |
961 | goto out; | |
962 | } | |
963 | ||
0706f1c4 SR |
964 | ret = register_ftrace_profiler(); |
965 | if (ret < 0) { | |
966 | cnt = ret; | |
967 | goto out; | |
968 | } | |
bac429f0 SR |
969 | ftrace_profile_enabled = 1; |
970 | } else { | |
971 | ftrace_profile_enabled = 0; | |
0f6ce3de SR |
972 | /* |
973 | * unregister_ftrace_profiler calls stop_machine | |
974 | * so this acts like an synchronize_sched. | |
975 | */ | |
0706f1c4 | 976 | unregister_ftrace_profiler(); |
bac429f0 SR |
977 | } |
978 | } | |
493762fc | 979 | out: |
bac429f0 SR |
980 | mutex_unlock(&ftrace_profile_lock); |
981 | ||
cf8517cf | 982 | *ppos += cnt; |
bac429f0 SR |
983 | |
984 | return cnt; | |
985 | } | |
986 | ||
493762fc SR |
987 | static ssize_t |
988 | ftrace_profile_read(struct file *filp, char __user *ubuf, | |
989 | size_t cnt, loff_t *ppos) | |
990 | { | |
fb9fb015 | 991 | char buf[64]; /* big enough to hold a number */ |
493762fc SR |
992 | int r; |
993 | ||
994 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | |
995 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
996 | } | |
997 | ||
bac429f0 SR |
998 | static const struct file_operations ftrace_profile_fops = { |
999 | .open = tracing_open_generic, | |
1000 | .read = ftrace_profile_read, | |
1001 | .write = ftrace_profile_write, | |
6038f373 | 1002 | .llseek = default_llseek, |
bac429f0 SR |
1003 | }; |
1004 | ||
cafb168a SR |
1005 | /* used to initialize the real stat files */ |
1006 | static struct tracer_stat function_stats __initdata = { | |
fb9fb015 SR |
1007 | .name = "functions", |
1008 | .stat_start = function_stat_start, | |
1009 | .stat_next = function_stat_next, | |
1010 | .stat_cmp = function_stat_cmp, | |
1011 | .stat_headers = function_stat_headers, | |
1012 | .stat_show = function_stat_show | |
cafb168a SR |
1013 | }; |
1014 | ||
6ab5d668 | 1015 | static __init void ftrace_profile_debugfs(struct dentry *d_tracer) |
bac429f0 | 1016 | { |
cafb168a | 1017 | struct ftrace_profile_stat *stat; |
bac429f0 | 1018 | struct dentry *entry; |
cafb168a | 1019 | char *name; |
bac429f0 | 1020 | int ret; |
cafb168a SR |
1021 | int cpu; |
1022 | ||
1023 | for_each_possible_cpu(cpu) { | |
1024 | stat = &per_cpu(ftrace_profile_stats, cpu); | |
1025 | ||
1026 | /* allocate enough for function name + cpu number */ | |
1027 | name = kmalloc(32, GFP_KERNEL); | |
1028 | if (!name) { | |
1029 | /* | |
1030 | * The files created are permanent, if something happens | |
1031 | * we still do not free memory. | |
1032 | */ | |
cafb168a SR |
1033 | WARN(1, |
1034 | "Could not allocate stat file for cpu %d\n", | |
1035 | cpu); | |
1036 | return; | |
1037 | } | |
1038 | stat->stat = function_stats; | |
1039 | snprintf(name, 32, "function%d", cpu); | |
1040 | stat->stat.name = name; | |
1041 | ret = register_stat_tracer(&stat->stat); | |
1042 | if (ret) { | |
1043 | WARN(1, | |
1044 | "Could not register function stat for cpu %d\n", | |
1045 | cpu); | |
1046 | kfree(name); | |
1047 | return; | |
1048 | } | |
bac429f0 SR |
1049 | } |
1050 | ||
1051 | entry = debugfs_create_file("function_profile_enabled", 0644, | |
1052 | d_tracer, NULL, &ftrace_profile_fops); | |
1053 | if (!entry) | |
1054 | pr_warning("Could not create debugfs " | |
1055 | "'function_profile_enabled' entry\n"); | |
1056 | } | |
1057 | ||
bac429f0 | 1058 | #else /* CONFIG_FUNCTION_PROFILER */ |
6ab5d668 | 1059 | static __init void ftrace_profile_debugfs(struct dentry *d_tracer) |
bac429f0 SR |
1060 | { |
1061 | } | |
bac429f0 SR |
1062 | #endif /* CONFIG_FUNCTION_PROFILER */ |
1063 | ||
493762fc SR |
1064 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; |
1065 | ||
7f49ef69 SRRH |
1066 | loff_t |
1067 | ftrace_filter_lseek(struct file *file, loff_t offset, int whence) | |
1068 | { | |
1069 | loff_t ret; | |
1070 | ||
1071 | if (file->f_mode & FMODE_READ) | |
1072 | ret = seq_lseek(file, offset, whence); | |
1073 | else | |
1074 | file->f_pos = ret = 1; | |
1075 | ||
1076 | return ret; | |
1077 | } | |
1078 | ||
493762fc SR |
1079 | #ifdef CONFIG_DYNAMIC_FTRACE |
1080 | ||
1081 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD | |
1082 | # error Dynamic ftrace depends on MCOUNT_RECORD | |
1083 | #endif | |
1084 | ||
1085 | static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly; | |
1086 | ||
1087 | struct ftrace_func_probe { | |
1088 | struct hlist_node node; | |
1089 | struct ftrace_probe_ops *ops; | |
1090 | unsigned long flags; | |
1091 | unsigned long ip; | |
1092 | void *data; | |
7818b388 | 1093 | struct list_head free_list; |
493762fc SR |
1094 | }; |
1095 | ||
b448c4e3 SR |
1096 | struct ftrace_func_entry { |
1097 | struct hlist_node hlist; | |
1098 | unsigned long ip; | |
1099 | }; | |
1100 | ||
1101 | struct ftrace_hash { | |
1102 | unsigned long size_bits; | |
1103 | struct hlist_head *buckets; | |
1104 | unsigned long count; | |
07fd5515 | 1105 | struct rcu_head rcu; |
b448c4e3 SR |
1106 | }; |
1107 | ||
33dc9b12 SR |
1108 | /* |
1109 | * We make these constant because no one should touch them, | |
1110 | * but they are used as the default "empty hash", to avoid allocating | |
1111 | * it all the time. These are in a read only section such that if | |
1112 | * anyone does try to modify it, it will cause an exception. | |
1113 | */ | |
1114 | static const struct hlist_head empty_buckets[1]; | |
1115 | static const struct ftrace_hash empty_hash = { | |
1116 | .buckets = (struct hlist_head *)empty_buckets, | |
1cf41dd7 | 1117 | }; |
33dc9b12 | 1118 | #define EMPTY_HASH ((struct ftrace_hash *)&empty_hash) |
493762fc | 1119 | |
2b499381 | 1120 | static struct ftrace_ops global_ops = { |
f45948e8 | 1121 | .func = ftrace_stub, |
33dc9b12 SR |
1122 | .notrace_hash = EMPTY_HASH, |
1123 | .filter_hash = EMPTY_HASH, | |
f04f24fb MH |
1124 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, |
1125 | INIT_REGEX_LOCK(global_ops) | |
f45948e8 SR |
1126 | }; |
1127 | ||
493762fc SR |
1128 | struct ftrace_page { |
1129 | struct ftrace_page *next; | |
a7900875 | 1130 | struct dyn_ftrace *records; |
493762fc | 1131 | int index; |
a7900875 | 1132 | int size; |
493762fc SR |
1133 | }; |
1134 | ||
85ae32ae SR |
1135 | static struct ftrace_page *ftrace_new_pgs; |
1136 | ||
a7900875 SR |
1137 | #define ENTRY_SIZE sizeof(struct dyn_ftrace) |
1138 | #define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE) | |
493762fc SR |
1139 | |
1140 | /* estimate from running different kernels */ | |
1141 | #define NR_TO_INIT 10000 | |
1142 | ||
1143 | static struct ftrace_page *ftrace_pages_start; | |
1144 | static struct ftrace_page *ftrace_pages; | |
1145 | ||
06a51d93 SR |
1146 | static bool ftrace_hash_empty(struct ftrace_hash *hash) |
1147 | { | |
1148 | return !hash || !hash->count; | |
1149 | } | |
1150 | ||
b448c4e3 SR |
1151 | static struct ftrace_func_entry * |
1152 | ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
1153 | { | |
1154 | unsigned long key; | |
1155 | struct ftrace_func_entry *entry; | |
1156 | struct hlist_head *hhd; | |
b448c4e3 | 1157 | |
06a51d93 | 1158 | if (ftrace_hash_empty(hash)) |
b448c4e3 SR |
1159 | return NULL; |
1160 | ||
1161 | if (hash->size_bits > 0) | |
1162 | key = hash_long(ip, hash->size_bits); | |
1163 | else | |
1164 | key = 0; | |
1165 | ||
1166 | hhd = &hash->buckets[key]; | |
1167 | ||
b67bfe0d | 1168 | hlist_for_each_entry_rcu(entry, hhd, hlist) { |
b448c4e3 SR |
1169 | if (entry->ip == ip) |
1170 | return entry; | |
1171 | } | |
1172 | return NULL; | |
1173 | } | |
1174 | ||
33dc9b12 SR |
1175 | static void __add_hash_entry(struct ftrace_hash *hash, |
1176 | struct ftrace_func_entry *entry) | |
b448c4e3 | 1177 | { |
b448c4e3 SR |
1178 | struct hlist_head *hhd; |
1179 | unsigned long key; | |
1180 | ||
b448c4e3 | 1181 | if (hash->size_bits) |
33dc9b12 | 1182 | key = hash_long(entry->ip, hash->size_bits); |
b448c4e3 SR |
1183 | else |
1184 | key = 0; | |
1185 | ||
b448c4e3 SR |
1186 | hhd = &hash->buckets[key]; |
1187 | hlist_add_head(&entry->hlist, hhd); | |
1188 | hash->count++; | |
33dc9b12 SR |
1189 | } |
1190 | ||
1191 | static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) | |
1192 | { | |
1193 | struct ftrace_func_entry *entry; | |
1194 | ||
1195 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
1196 | if (!entry) | |
1197 | return -ENOMEM; | |
1198 | ||
1199 | entry->ip = ip; | |
1200 | __add_hash_entry(hash, entry); | |
b448c4e3 SR |
1201 | |
1202 | return 0; | |
1203 | } | |
1204 | ||
1205 | static void | |
33dc9b12 | 1206 | free_hash_entry(struct ftrace_hash *hash, |
b448c4e3 SR |
1207 | struct ftrace_func_entry *entry) |
1208 | { | |
1209 | hlist_del(&entry->hlist); | |
1210 | kfree(entry); | |
1211 | hash->count--; | |
1212 | } | |
1213 | ||
33dc9b12 SR |
1214 | static void |
1215 | remove_hash_entry(struct ftrace_hash *hash, | |
1216 | struct ftrace_func_entry *entry) | |
1217 | { | |
1218 | hlist_del(&entry->hlist); | |
1219 | hash->count--; | |
1220 | } | |
1221 | ||
b448c4e3 SR |
1222 | static void ftrace_hash_clear(struct ftrace_hash *hash) |
1223 | { | |
1224 | struct hlist_head *hhd; | |
b67bfe0d | 1225 | struct hlist_node *tn; |
b448c4e3 SR |
1226 | struct ftrace_func_entry *entry; |
1227 | int size = 1 << hash->size_bits; | |
1228 | int i; | |
1229 | ||
33dc9b12 SR |
1230 | if (!hash->count) |
1231 | return; | |
1232 | ||
b448c4e3 SR |
1233 | for (i = 0; i < size; i++) { |
1234 | hhd = &hash->buckets[i]; | |
b67bfe0d | 1235 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) |
33dc9b12 | 1236 | free_hash_entry(hash, entry); |
b448c4e3 SR |
1237 | } |
1238 | FTRACE_WARN_ON(hash->count); | |
1239 | } | |
1240 | ||
33dc9b12 SR |
1241 | static void free_ftrace_hash(struct ftrace_hash *hash) |
1242 | { | |
1243 | if (!hash || hash == EMPTY_HASH) | |
1244 | return; | |
1245 | ftrace_hash_clear(hash); | |
1246 | kfree(hash->buckets); | |
1247 | kfree(hash); | |
1248 | } | |
1249 | ||
07fd5515 SR |
1250 | static void __free_ftrace_hash_rcu(struct rcu_head *rcu) |
1251 | { | |
1252 | struct ftrace_hash *hash; | |
1253 | ||
1254 | hash = container_of(rcu, struct ftrace_hash, rcu); | |
1255 | free_ftrace_hash(hash); | |
1256 | } | |
1257 | ||
1258 | static void free_ftrace_hash_rcu(struct ftrace_hash *hash) | |
1259 | { | |
1260 | if (!hash || hash == EMPTY_HASH) | |
1261 | return; | |
1262 | call_rcu_sched(&hash->rcu, __free_ftrace_hash_rcu); | |
1263 | } | |
1264 | ||
5500fa51 JO |
1265 | void ftrace_free_filter(struct ftrace_ops *ops) |
1266 | { | |
f04f24fb | 1267 | ftrace_ops_init(ops); |
5500fa51 JO |
1268 | free_ftrace_hash(ops->filter_hash); |
1269 | free_ftrace_hash(ops->notrace_hash); | |
1270 | } | |
1271 | ||
33dc9b12 SR |
1272 | static struct ftrace_hash *alloc_ftrace_hash(int size_bits) |
1273 | { | |
1274 | struct ftrace_hash *hash; | |
1275 | int size; | |
1276 | ||
1277 | hash = kzalloc(sizeof(*hash), GFP_KERNEL); | |
1278 | if (!hash) | |
1279 | return NULL; | |
1280 | ||
1281 | size = 1 << size_bits; | |
47b0edcb | 1282 | hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL); |
33dc9b12 SR |
1283 | |
1284 | if (!hash->buckets) { | |
1285 | kfree(hash); | |
1286 | return NULL; | |
1287 | } | |
1288 | ||
1289 | hash->size_bits = size_bits; | |
1290 | ||
1291 | return hash; | |
1292 | } | |
1293 | ||
1294 | static struct ftrace_hash * | |
1295 | alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) | |
1296 | { | |
1297 | struct ftrace_func_entry *entry; | |
1298 | struct ftrace_hash *new_hash; | |
33dc9b12 SR |
1299 | int size; |
1300 | int ret; | |
1301 | int i; | |
1302 | ||
1303 | new_hash = alloc_ftrace_hash(size_bits); | |
1304 | if (!new_hash) | |
1305 | return NULL; | |
1306 | ||
1307 | /* Empty hash? */ | |
06a51d93 | 1308 | if (ftrace_hash_empty(hash)) |
33dc9b12 SR |
1309 | return new_hash; |
1310 | ||
1311 | size = 1 << hash->size_bits; | |
1312 | for (i = 0; i < size; i++) { | |
b67bfe0d | 1313 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { |
33dc9b12 SR |
1314 | ret = add_hash_entry(new_hash, entry->ip); |
1315 | if (ret < 0) | |
1316 | goto free_hash; | |
1317 | } | |
1318 | } | |
1319 | ||
1320 | FTRACE_WARN_ON(new_hash->count != hash->count); | |
1321 | ||
1322 | return new_hash; | |
1323 | ||
1324 | free_hash: | |
1325 | free_ftrace_hash(new_hash); | |
1326 | return NULL; | |
1327 | } | |
1328 | ||
41fb61c2 SR |
1329 | static void |
1330 | ftrace_hash_rec_disable(struct ftrace_ops *ops, int filter_hash); | |
1331 | static void | |
1332 | ftrace_hash_rec_enable(struct ftrace_ops *ops, int filter_hash); | |
1333 | ||
33dc9b12 | 1334 | static int |
41fb61c2 SR |
1335 | ftrace_hash_move(struct ftrace_ops *ops, int enable, |
1336 | struct ftrace_hash **dst, struct ftrace_hash *src) | |
33dc9b12 SR |
1337 | { |
1338 | struct ftrace_func_entry *entry; | |
b67bfe0d | 1339 | struct hlist_node *tn; |
33dc9b12 | 1340 | struct hlist_head *hhd; |
07fd5515 SR |
1341 | struct ftrace_hash *old_hash; |
1342 | struct ftrace_hash *new_hash; | |
33dc9b12 SR |
1343 | int size = src->count; |
1344 | int bits = 0; | |
41fb61c2 | 1345 | int ret; |
33dc9b12 SR |
1346 | int i; |
1347 | ||
41fb61c2 SR |
1348 | /* |
1349 | * Remove the current set, update the hash and add | |
1350 | * them back. | |
1351 | */ | |
1352 | ftrace_hash_rec_disable(ops, enable); | |
1353 | ||
33dc9b12 SR |
1354 | /* |
1355 | * If the new source is empty, just free dst and assign it | |
1356 | * the empty_hash. | |
1357 | */ | |
1358 | if (!src->count) { | |
07fd5515 SR |
1359 | free_ftrace_hash_rcu(*dst); |
1360 | rcu_assign_pointer(*dst, EMPTY_HASH); | |
d4d34b98 SR |
1361 | /* still need to update the function records */ |
1362 | ret = 0; | |
1363 | goto out; | |
33dc9b12 SR |
1364 | } |
1365 | ||
33dc9b12 SR |
1366 | /* |
1367 | * Make the hash size about 1/2 the # found | |
1368 | */ | |
1369 | for (size /= 2; size; size >>= 1) | |
1370 | bits++; | |
1371 | ||
1372 | /* Don't allocate too much */ | |
1373 | if (bits > FTRACE_HASH_MAX_BITS) | |
1374 | bits = FTRACE_HASH_MAX_BITS; | |
1375 | ||
41fb61c2 | 1376 | ret = -ENOMEM; |
07fd5515 SR |
1377 | new_hash = alloc_ftrace_hash(bits); |
1378 | if (!new_hash) | |
41fb61c2 | 1379 | goto out; |
33dc9b12 SR |
1380 | |
1381 | size = 1 << src->size_bits; | |
1382 | for (i = 0; i < size; i++) { | |
1383 | hhd = &src->buckets[i]; | |
b67bfe0d | 1384 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) { |
33dc9b12 | 1385 | remove_hash_entry(src, entry); |
07fd5515 | 1386 | __add_hash_entry(new_hash, entry); |
33dc9b12 SR |
1387 | } |
1388 | } | |
1389 | ||
07fd5515 SR |
1390 | old_hash = *dst; |
1391 | rcu_assign_pointer(*dst, new_hash); | |
1392 | free_ftrace_hash_rcu(old_hash); | |
1393 | ||
41fb61c2 SR |
1394 | ret = 0; |
1395 | out: | |
1396 | /* | |
1397 | * Enable regardless of ret: | |
1398 | * On success, we enable the new hash. | |
1399 | * On failure, we re-enable the original hash. | |
1400 | */ | |
1401 | ftrace_hash_rec_enable(ops, enable); | |
1402 | ||
1403 | return ret; | |
33dc9b12 SR |
1404 | } |
1405 | ||
b848914c SR |
1406 | /* |
1407 | * Test the hashes for this ops to see if we want to call | |
1408 | * the ops->func or not. | |
1409 | * | |
1410 | * It's a match if the ip is in the ops->filter_hash or | |
1411 | * the filter_hash does not exist or is empty, | |
1412 | * AND | |
1413 | * the ip is not in the ops->notrace_hash. | |
cdbe61bf SR |
1414 | * |
1415 | * This needs to be called with preemption disabled as | |
1416 | * the hashes are freed with call_rcu_sched(). | |
b848914c SR |
1417 | */ |
1418 | static int | |
1419 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip) | |
1420 | { | |
1421 | struct ftrace_hash *filter_hash; | |
1422 | struct ftrace_hash *notrace_hash; | |
1423 | int ret; | |
1424 | ||
b848914c SR |
1425 | filter_hash = rcu_dereference_raw(ops->filter_hash); |
1426 | notrace_hash = rcu_dereference_raw(ops->notrace_hash); | |
1427 | ||
06a51d93 | 1428 | if ((ftrace_hash_empty(filter_hash) || |
b848914c | 1429 | ftrace_lookup_ip(filter_hash, ip)) && |
06a51d93 | 1430 | (ftrace_hash_empty(notrace_hash) || |
b848914c SR |
1431 | !ftrace_lookup_ip(notrace_hash, ip))) |
1432 | ret = 1; | |
1433 | else | |
1434 | ret = 0; | |
b848914c SR |
1435 | |
1436 | return ret; | |
1437 | } | |
1438 | ||
493762fc SR |
1439 | /* |
1440 | * This is a double for. Do not use 'break' to break out of the loop, | |
1441 | * you must use a goto. | |
1442 | */ | |
1443 | #define do_for_each_ftrace_rec(pg, rec) \ | |
1444 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
1445 | int _____i; \ | |
1446 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
1447 | rec = &pg->records[_____i]; | |
1448 | ||
1449 | #define while_for_each_ftrace_rec() \ | |
1450 | } \ | |
1451 | } | |
1452 | ||
5855fead SR |
1453 | |
1454 | static int ftrace_cmp_recs(const void *a, const void *b) | |
1455 | { | |
a650e02a SR |
1456 | const struct dyn_ftrace *key = a; |
1457 | const struct dyn_ftrace *rec = b; | |
5855fead | 1458 | |
a650e02a | 1459 | if (key->flags < rec->ip) |
5855fead | 1460 | return -1; |
a650e02a SR |
1461 | if (key->ip >= rec->ip + MCOUNT_INSN_SIZE) |
1462 | return 1; | |
5855fead SR |
1463 | return 0; |
1464 | } | |
1465 | ||
f0cf973a | 1466 | static unsigned long ftrace_location_range(unsigned long start, unsigned long end) |
c88fd863 SR |
1467 | { |
1468 | struct ftrace_page *pg; | |
1469 | struct dyn_ftrace *rec; | |
5855fead | 1470 | struct dyn_ftrace key; |
c88fd863 | 1471 | |
a650e02a SR |
1472 | key.ip = start; |
1473 | key.flags = end; /* overload flags, as it is unsigned long */ | |
5855fead SR |
1474 | |
1475 | for (pg = ftrace_pages_start; pg; pg = pg->next) { | |
a650e02a SR |
1476 | if (end < pg->records[0].ip || |
1477 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) | |
9644302e | 1478 | continue; |
5855fead SR |
1479 | rec = bsearch(&key, pg->records, pg->index, |
1480 | sizeof(struct dyn_ftrace), | |
1481 | ftrace_cmp_recs); | |
1482 | if (rec) | |
f0cf973a | 1483 | return rec->ip; |
5855fead | 1484 | } |
c88fd863 SR |
1485 | |
1486 | return 0; | |
1487 | } | |
1488 | ||
a650e02a SR |
1489 | /** |
1490 | * ftrace_location - return true if the ip giving is a traced location | |
1491 | * @ip: the instruction pointer to check | |
1492 | * | |
f0cf973a | 1493 | * Returns rec->ip if @ip given is a pointer to a ftrace location. |
a650e02a SR |
1494 | * That is, the instruction that is either a NOP or call to |
1495 | * the function tracer. It checks the ftrace internal tables to | |
1496 | * determine if the address belongs or not. | |
1497 | */ | |
f0cf973a | 1498 | unsigned long ftrace_location(unsigned long ip) |
a650e02a SR |
1499 | { |
1500 | return ftrace_location_range(ip, ip); | |
1501 | } | |
1502 | ||
1503 | /** | |
1504 | * ftrace_text_reserved - return true if range contains an ftrace location | |
1505 | * @start: start of range to search | |
1506 | * @end: end of range to search (inclusive). @end points to the last byte to check. | |
1507 | * | |
1508 | * Returns 1 if @start and @end contains a ftrace location. | |
1509 | * That is, the instruction that is either a NOP or call to | |
1510 | * the function tracer. It checks the ftrace internal tables to | |
1511 | * determine if the address belongs or not. | |
1512 | */ | |
1513 | int ftrace_text_reserved(void *start, void *end) | |
1514 | { | |
f0cf973a SR |
1515 | unsigned long ret; |
1516 | ||
1517 | ret = ftrace_location_range((unsigned long)start, | |
1518 | (unsigned long)end); | |
1519 | ||
1520 | return (int)!!ret; | |
a650e02a SR |
1521 | } |
1522 | ||
ed926f9b SR |
1523 | static void __ftrace_hash_rec_update(struct ftrace_ops *ops, |
1524 | int filter_hash, | |
1525 | bool inc) | |
1526 | { | |
1527 | struct ftrace_hash *hash; | |
1528 | struct ftrace_hash *other_hash; | |
1529 | struct ftrace_page *pg; | |
1530 | struct dyn_ftrace *rec; | |
1531 | int count = 0; | |
1532 | int all = 0; | |
1533 | ||
1534 | /* Only update if the ops has been registered */ | |
1535 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
1536 | return; | |
1537 | ||
1538 | /* | |
1539 | * In the filter_hash case: | |
1540 | * If the count is zero, we update all records. | |
1541 | * Otherwise we just update the items in the hash. | |
1542 | * | |
1543 | * In the notrace_hash case: | |
1544 | * We enable the update in the hash. | |
1545 | * As disabling notrace means enabling the tracing, | |
1546 | * and enabling notrace means disabling, the inc variable | |
1547 | * gets inversed. | |
1548 | */ | |
1549 | if (filter_hash) { | |
1550 | hash = ops->filter_hash; | |
1551 | other_hash = ops->notrace_hash; | |
06a51d93 | 1552 | if (ftrace_hash_empty(hash)) |
ed926f9b SR |
1553 | all = 1; |
1554 | } else { | |
1555 | inc = !inc; | |
1556 | hash = ops->notrace_hash; | |
1557 | other_hash = ops->filter_hash; | |
1558 | /* | |
1559 | * If the notrace hash has no items, | |
1560 | * then there's nothing to do. | |
1561 | */ | |
06a51d93 | 1562 | if (ftrace_hash_empty(hash)) |
ed926f9b SR |
1563 | return; |
1564 | } | |
1565 | ||
1566 | do_for_each_ftrace_rec(pg, rec) { | |
1567 | int in_other_hash = 0; | |
1568 | int in_hash = 0; | |
1569 | int match = 0; | |
1570 | ||
1571 | if (all) { | |
1572 | /* | |
1573 | * Only the filter_hash affects all records. | |
1574 | * Update if the record is not in the notrace hash. | |
1575 | */ | |
b848914c | 1576 | if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip)) |
ed926f9b SR |
1577 | match = 1; |
1578 | } else { | |
06a51d93 SR |
1579 | in_hash = !!ftrace_lookup_ip(hash, rec->ip); |
1580 | in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip); | |
ed926f9b SR |
1581 | |
1582 | /* | |
1583 | * | |
1584 | */ | |
1585 | if (filter_hash && in_hash && !in_other_hash) | |
1586 | match = 1; | |
1587 | else if (!filter_hash && in_hash && | |
06a51d93 | 1588 | (in_other_hash || ftrace_hash_empty(other_hash))) |
ed926f9b SR |
1589 | match = 1; |
1590 | } | |
1591 | if (!match) | |
1592 | continue; | |
1593 | ||
1594 | if (inc) { | |
1595 | rec->flags++; | |
1596 | if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == FTRACE_REF_MAX)) | |
1597 | return; | |
08f6fba5 SR |
1598 | /* |
1599 | * If any ops wants regs saved for this function | |
1600 | * then all ops will get saved regs. | |
1601 | */ | |
1602 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) | |
1603 | rec->flags |= FTRACE_FL_REGS; | |
ed926f9b SR |
1604 | } else { |
1605 | if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == 0)) | |
1606 | return; | |
1607 | rec->flags--; | |
1608 | } | |
1609 | count++; | |
1610 | /* Shortcut, if we handled all records, we are done. */ | |
1611 | if (!all && count == hash->count) | |
1612 | return; | |
1613 | } while_for_each_ftrace_rec(); | |
1614 | } | |
1615 | ||
1616 | static void ftrace_hash_rec_disable(struct ftrace_ops *ops, | |
1617 | int filter_hash) | |
1618 | { | |
1619 | __ftrace_hash_rec_update(ops, filter_hash, 0); | |
1620 | } | |
1621 | ||
1622 | static void ftrace_hash_rec_enable(struct ftrace_ops *ops, | |
1623 | int filter_hash) | |
1624 | { | |
1625 | __ftrace_hash_rec_update(ops, filter_hash, 1); | |
1626 | } | |
1627 | ||
b17e8a37 SR |
1628 | static void print_ip_ins(const char *fmt, unsigned char *p) |
1629 | { | |
1630 | int i; | |
1631 | ||
1632 | printk(KERN_CONT "%s", fmt); | |
1633 | ||
1634 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
1635 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
1636 | } | |
1637 | ||
c88fd863 SR |
1638 | /** |
1639 | * ftrace_bug - report and shutdown function tracer | |
1640 | * @failed: The failed type (EFAULT, EINVAL, EPERM) | |
1641 | * @ip: The address that failed | |
1642 | * | |
1643 | * The arch code that enables or disables the function tracing | |
1644 | * can call ftrace_bug() when it has detected a problem in | |
1645 | * modifying the code. @failed should be one of either: | |
1646 | * EFAULT - if the problem happens on reading the @ip address | |
1647 | * EINVAL - if what is read at @ip is not what was expected | |
1648 | * EPERM - if the problem happens on writting to the @ip address | |
1649 | */ | |
1650 | void ftrace_bug(int failed, unsigned long ip) | |
b17e8a37 SR |
1651 | { |
1652 | switch (failed) { | |
1653 | case -EFAULT: | |
1654 | FTRACE_WARN_ON_ONCE(1); | |
1655 | pr_info("ftrace faulted on modifying "); | |
1656 | print_ip_sym(ip); | |
1657 | break; | |
1658 | case -EINVAL: | |
1659 | FTRACE_WARN_ON_ONCE(1); | |
1660 | pr_info("ftrace failed to modify "); | |
1661 | print_ip_sym(ip); | |
b17e8a37 | 1662 | print_ip_ins(" actual: ", (unsigned char *)ip); |
b17e8a37 SR |
1663 | printk(KERN_CONT "\n"); |
1664 | break; | |
1665 | case -EPERM: | |
1666 | FTRACE_WARN_ON_ONCE(1); | |
1667 | pr_info("ftrace faulted on writing "); | |
1668 | print_ip_sym(ip); | |
1669 | break; | |
1670 | default: | |
1671 | FTRACE_WARN_ON_ONCE(1); | |
1672 | pr_info("ftrace faulted on unknown error "); | |
1673 | print_ip_sym(ip); | |
1674 | } | |
1675 | } | |
1676 | ||
c88fd863 | 1677 | static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update) |
5072c59f | 1678 | { |
64fbcd16 | 1679 | unsigned long flag = 0UL; |
e7d3737e | 1680 | |
982c350b | 1681 | /* |
30fb6aa7 | 1682 | * If we are updating calls: |
982c350b | 1683 | * |
ed926f9b SR |
1684 | * If the record has a ref count, then we need to enable it |
1685 | * because someone is using it. | |
982c350b | 1686 | * |
ed926f9b SR |
1687 | * Otherwise we make sure its disabled. |
1688 | * | |
30fb6aa7 | 1689 | * If we are disabling calls, then disable all records that |
ed926f9b | 1690 | * are enabled. |
982c350b | 1691 | */ |
c88fd863 | 1692 | if (enable && (rec->flags & ~FTRACE_FL_MASK)) |
ed926f9b | 1693 | flag = FTRACE_FL_ENABLED; |
982c350b | 1694 | |
08f6fba5 SR |
1695 | /* |
1696 | * If enabling and the REGS flag does not match the REGS_EN, then | |
1697 | * do not ignore this record. Set flags to fail the compare against | |
1698 | * ENABLED. | |
1699 | */ | |
1700 | if (flag && | |
1701 | (!(rec->flags & FTRACE_FL_REGS) != !(rec->flags & FTRACE_FL_REGS_EN))) | |
1702 | flag |= FTRACE_FL_REGS; | |
1703 | ||
64fbcd16 XG |
1704 | /* If the state of this record hasn't changed, then do nothing */ |
1705 | if ((rec->flags & FTRACE_FL_ENABLED) == flag) | |
c88fd863 | 1706 | return FTRACE_UPDATE_IGNORE; |
982c350b | 1707 | |
64fbcd16 | 1708 | if (flag) { |
08f6fba5 SR |
1709 | /* Save off if rec is being enabled (for return value) */ |
1710 | flag ^= rec->flags & FTRACE_FL_ENABLED; | |
1711 | ||
1712 | if (update) { | |
c88fd863 | 1713 | rec->flags |= FTRACE_FL_ENABLED; |
08f6fba5 SR |
1714 | if (flag & FTRACE_FL_REGS) { |
1715 | if (rec->flags & FTRACE_FL_REGS) | |
1716 | rec->flags |= FTRACE_FL_REGS_EN; | |
1717 | else | |
1718 | rec->flags &= ~FTRACE_FL_REGS_EN; | |
1719 | } | |
1720 | } | |
1721 | ||
1722 | /* | |
1723 | * If this record is being updated from a nop, then | |
1724 | * return UPDATE_MAKE_CALL. | |
1725 | * Otherwise, if the EN flag is set, then return | |
1726 | * UPDATE_MODIFY_CALL_REGS to tell the caller to convert | |
1727 | * from the non-save regs, to a save regs function. | |
1728 | * Otherwise, | |
1729 | * return UPDATE_MODIFY_CALL to tell the caller to convert | |
1730 | * from the save regs, to a non-save regs function. | |
1731 | */ | |
1732 | if (flag & FTRACE_FL_ENABLED) | |
1733 | return FTRACE_UPDATE_MAKE_CALL; | |
1734 | else if (rec->flags & FTRACE_FL_REGS_EN) | |
1735 | return FTRACE_UPDATE_MODIFY_CALL_REGS; | |
1736 | else | |
1737 | return FTRACE_UPDATE_MODIFY_CALL; | |
c88fd863 SR |
1738 | } |
1739 | ||
08f6fba5 SR |
1740 | if (update) { |
1741 | /* If there's no more users, clear all flags */ | |
1742 | if (!(rec->flags & ~FTRACE_FL_MASK)) | |
1743 | rec->flags = 0; | |
1744 | else | |
1745 | /* Just disable the record (keep REGS state) */ | |
1746 | rec->flags &= ~FTRACE_FL_ENABLED; | |
1747 | } | |
c88fd863 SR |
1748 | |
1749 | return FTRACE_UPDATE_MAKE_NOP; | |
1750 | } | |
1751 | ||
1752 | /** | |
1753 | * ftrace_update_record, set a record that now is tracing or not | |
1754 | * @rec: the record to update | |
1755 | * @enable: set to 1 if the record is tracing, zero to force disable | |
1756 | * | |
1757 | * The records that represent all functions that can be traced need | |
1758 | * to be updated when tracing has been enabled. | |
1759 | */ | |
1760 | int ftrace_update_record(struct dyn_ftrace *rec, int enable) | |
1761 | { | |
1762 | return ftrace_check_record(rec, enable, 1); | |
1763 | } | |
1764 | ||
1765 | /** | |
1766 | * ftrace_test_record, check if the record has been enabled or not | |
1767 | * @rec: the record to test | |
1768 | * @enable: set to 1 to check if enabled, 0 if it is disabled | |
1769 | * | |
1770 | * The arch code may need to test if a record is already set to | |
1771 | * tracing to determine how to modify the function code that it | |
1772 | * represents. | |
1773 | */ | |
1774 | int ftrace_test_record(struct dyn_ftrace *rec, int enable) | |
1775 | { | |
1776 | return ftrace_check_record(rec, enable, 0); | |
1777 | } | |
1778 | ||
1779 | static int | |
1780 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) | |
1781 | { | |
08f6fba5 | 1782 | unsigned long ftrace_old_addr; |
c88fd863 SR |
1783 | unsigned long ftrace_addr; |
1784 | int ret; | |
1785 | ||
c88fd863 SR |
1786 | ret = ftrace_update_record(rec, enable); |
1787 | ||
08f6fba5 SR |
1788 | if (rec->flags & FTRACE_FL_REGS) |
1789 | ftrace_addr = (unsigned long)FTRACE_REGS_ADDR; | |
1790 | else | |
1791 | ftrace_addr = (unsigned long)FTRACE_ADDR; | |
1792 | ||
c88fd863 SR |
1793 | switch (ret) { |
1794 | case FTRACE_UPDATE_IGNORE: | |
1795 | return 0; | |
1796 | ||
1797 | case FTRACE_UPDATE_MAKE_CALL: | |
64fbcd16 | 1798 | return ftrace_make_call(rec, ftrace_addr); |
c88fd863 SR |
1799 | |
1800 | case FTRACE_UPDATE_MAKE_NOP: | |
1801 | return ftrace_make_nop(NULL, rec, ftrace_addr); | |
08f6fba5 SR |
1802 | |
1803 | case FTRACE_UPDATE_MODIFY_CALL_REGS: | |
1804 | case FTRACE_UPDATE_MODIFY_CALL: | |
1805 | if (rec->flags & FTRACE_FL_REGS) | |
1806 | ftrace_old_addr = (unsigned long)FTRACE_ADDR; | |
1807 | else | |
1808 | ftrace_old_addr = (unsigned long)FTRACE_REGS_ADDR; | |
1809 | ||
1810 | return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr); | |
5072c59f SR |
1811 | } |
1812 | ||
c88fd863 | 1813 | return -1; /* unknow ftrace bug */ |
5072c59f SR |
1814 | } |
1815 | ||
e4f5d544 | 1816 | void __weak ftrace_replace_code(int enable) |
3c1720f0 | 1817 | { |
3c1720f0 SR |
1818 | struct dyn_ftrace *rec; |
1819 | struct ftrace_page *pg; | |
6a24a244 | 1820 | int failed; |
3c1720f0 | 1821 | |
45a4a237 SR |
1822 | if (unlikely(ftrace_disabled)) |
1823 | return; | |
1824 | ||
265c831c | 1825 | do_for_each_ftrace_rec(pg, rec) { |
e4f5d544 | 1826 | failed = __ftrace_replace_code(rec, enable); |
fa9d13cf | 1827 | if (failed) { |
3279ba37 SR |
1828 | ftrace_bug(failed, rec->ip); |
1829 | /* Stop processing */ | |
1830 | return; | |
3c1720f0 | 1831 | } |
265c831c | 1832 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
1833 | } |
1834 | ||
c88fd863 SR |
1835 | struct ftrace_rec_iter { |
1836 | struct ftrace_page *pg; | |
1837 | int index; | |
1838 | }; | |
1839 | ||
1840 | /** | |
1841 | * ftrace_rec_iter_start, start up iterating over traced functions | |
1842 | * | |
1843 | * Returns an iterator handle that is used to iterate over all | |
1844 | * the records that represent address locations where functions | |
1845 | * are traced. | |
1846 | * | |
1847 | * May return NULL if no records are available. | |
1848 | */ | |
1849 | struct ftrace_rec_iter *ftrace_rec_iter_start(void) | |
1850 | { | |
1851 | /* | |
1852 | * We only use a single iterator. | |
1853 | * Protected by the ftrace_lock mutex. | |
1854 | */ | |
1855 | static struct ftrace_rec_iter ftrace_rec_iter; | |
1856 | struct ftrace_rec_iter *iter = &ftrace_rec_iter; | |
1857 | ||
1858 | iter->pg = ftrace_pages_start; | |
1859 | iter->index = 0; | |
1860 | ||
1861 | /* Could have empty pages */ | |
1862 | while (iter->pg && !iter->pg->index) | |
1863 | iter->pg = iter->pg->next; | |
1864 | ||
1865 | if (!iter->pg) | |
1866 | return NULL; | |
1867 | ||
1868 | return iter; | |
1869 | } | |
1870 | ||
1871 | /** | |
1872 | * ftrace_rec_iter_next, get the next record to process. | |
1873 | * @iter: The handle to the iterator. | |
1874 | * | |
1875 | * Returns the next iterator after the given iterator @iter. | |
1876 | */ | |
1877 | struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter) | |
1878 | { | |
1879 | iter->index++; | |
1880 | ||
1881 | if (iter->index >= iter->pg->index) { | |
1882 | iter->pg = iter->pg->next; | |
1883 | iter->index = 0; | |
1884 | ||
1885 | /* Could have empty pages */ | |
1886 | while (iter->pg && !iter->pg->index) | |
1887 | iter->pg = iter->pg->next; | |
1888 | } | |
1889 | ||
1890 | if (!iter->pg) | |
1891 | return NULL; | |
1892 | ||
1893 | return iter; | |
1894 | } | |
1895 | ||
1896 | /** | |
1897 | * ftrace_rec_iter_record, get the record at the iterator location | |
1898 | * @iter: The current iterator location | |
1899 | * | |
1900 | * Returns the record that the current @iter is at. | |
1901 | */ | |
1902 | struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter) | |
1903 | { | |
1904 | return &iter->pg->records[iter->index]; | |
1905 | } | |
1906 | ||
492a7ea5 | 1907 | static int |
31e88909 | 1908 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 SR |
1909 | { |
1910 | unsigned long ip; | |
593eb8a2 | 1911 | int ret; |
3c1720f0 SR |
1912 | |
1913 | ip = rec->ip; | |
1914 | ||
45a4a237 SR |
1915 | if (unlikely(ftrace_disabled)) |
1916 | return 0; | |
1917 | ||
25aac9dc | 1918 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
593eb8a2 | 1919 | if (ret) { |
31e88909 | 1920 | ftrace_bug(ret, ip); |
492a7ea5 | 1921 | return 0; |
37ad5084 | 1922 | } |
492a7ea5 | 1923 | return 1; |
3c1720f0 SR |
1924 | } |
1925 | ||
000ab691 SR |
1926 | /* |
1927 | * archs can override this function if they must do something | |
1928 | * before the modifying code is performed. | |
1929 | */ | |
1930 | int __weak ftrace_arch_code_modify_prepare(void) | |
1931 | { | |
1932 | return 0; | |
1933 | } | |
1934 | ||
1935 | /* | |
1936 | * archs can override this function if they must do something | |
1937 | * after the modifying code is performed. | |
1938 | */ | |
1939 | int __weak ftrace_arch_code_modify_post_process(void) | |
1940 | { | |
1941 | return 0; | |
1942 | } | |
1943 | ||
8ed3e2cf | 1944 | void ftrace_modify_all_code(int command) |
3d083395 | 1945 | { |
8ed3e2cf | 1946 | if (command & FTRACE_UPDATE_CALLS) |
d61f82d0 | 1947 | ftrace_replace_code(1); |
8ed3e2cf | 1948 | else if (command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
1949 | ftrace_replace_code(0); |
1950 | ||
8ed3e2cf | 1951 | if (command & FTRACE_UPDATE_TRACE_FUNC) |
d61f82d0 SR |
1952 | ftrace_update_ftrace_func(ftrace_trace_function); |
1953 | ||
8ed3e2cf | 1954 | if (command & FTRACE_START_FUNC_RET) |
5a45cfe1 | 1955 | ftrace_enable_ftrace_graph_caller(); |
8ed3e2cf | 1956 | else if (command & FTRACE_STOP_FUNC_RET) |
5a45cfe1 | 1957 | ftrace_disable_ftrace_graph_caller(); |
8ed3e2cf SR |
1958 | } |
1959 | ||
1960 | static int __ftrace_modify_code(void *data) | |
1961 | { | |
1962 | int *command = data; | |
1963 | ||
1964 | ftrace_modify_all_code(*command); | |
5a45cfe1 | 1965 | |
d61f82d0 | 1966 | return 0; |
3d083395 SR |
1967 | } |
1968 | ||
c88fd863 SR |
1969 | /** |
1970 | * ftrace_run_stop_machine, go back to the stop machine method | |
1971 | * @command: The command to tell ftrace what to do | |
1972 | * | |
1973 | * If an arch needs to fall back to the stop machine method, the | |
1974 | * it can call this function. | |
1975 | */ | |
1976 | void ftrace_run_stop_machine(int command) | |
1977 | { | |
1978 | stop_machine(__ftrace_modify_code, &command, NULL); | |
1979 | } | |
1980 | ||
1981 | /** | |
1982 | * arch_ftrace_update_code, modify the code to trace or not trace | |
1983 | * @command: The command that needs to be done | |
1984 | * | |
1985 | * Archs can override this function if it does not need to | |
1986 | * run stop_machine() to modify code. | |
1987 | */ | |
1988 | void __weak arch_ftrace_update_code(int command) | |
1989 | { | |
1990 | ftrace_run_stop_machine(command); | |
1991 | } | |
1992 | ||
e309b41d | 1993 | static void ftrace_run_update_code(int command) |
3d083395 | 1994 | { |
000ab691 SR |
1995 | int ret; |
1996 | ||
1997 | ret = ftrace_arch_code_modify_prepare(); | |
1998 | FTRACE_WARN_ON(ret); | |
1999 | if (ret) | |
2000 | return; | |
c88fd863 SR |
2001 | /* |
2002 | * Do not call function tracer while we update the code. | |
2003 | * We are in stop machine. | |
2004 | */ | |
2005 | function_trace_stop++; | |
000ab691 | 2006 | |
c88fd863 SR |
2007 | /* |
2008 | * By default we use stop_machine() to modify the code. | |
2009 | * But archs can do what ever they want as long as it | |
2010 | * is safe. The stop_machine() is the safest, but also | |
2011 | * produces the most overhead. | |
2012 | */ | |
2013 | arch_ftrace_update_code(command); | |
2014 | ||
c88fd863 | 2015 | function_trace_stop--; |
000ab691 SR |
2016 | |
2017 | ret = ftrace_arch_code_modify_post_process(); | |
2018 | FTRACE_WARN_ON(ret); | |
3d083395 SR |
2019 | } |
2020 | ||
d61f82d0 | 2021 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 2022 | static int ftrace_start_up; |
b848914c | 2023 | static int global_start_up; |
df4fc315 SR |
2024 | |
2025 | static void ftrace_startup_enable(int command) | |
2026 | { | |
2027 | if (saved_ftrace_func != ftrace_trace_function) { | |
2028 | saved_ftrace_func = ftrace_trace_function; | |
2029 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2030 | } | |
2031 | ||
2032 | if (!command || !ftrace_enabled) | |
2033 | return; | |
2034 | ||
2035 | ftrace_run_update_code(command); | |
2036 | } | |
d61f82d0 | 2037 | |
a1cd6173 | 2038 | static int ftrace_startup(struct ftrace_ops *ops, int command) |
3d083395 | 2039 | { |
b848914c SR |
2040 | bool hash_enable = true; |
2041 | ||
4eebcc81 | 2042 | if (unlikely(ftrace_disabled)) |
a1cd6173 | 2043 | return -ENODEV; |
4eebcc81 | 2044 | |
60a7ecf4 | 2045 | ftrace_start_up++; |
30fb6aa7 | 2046 | command |= FTRACE_UPDATE_CALLS; |
d61f82d0 | 2047 | |
b848914c SR |
2048 | /* ops marked global share the filter hashes */ |
2049 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { | |
2050 | ops = &global_ops; | |
2051 | /* Don't update hash if global is already set */ | |
2052 | if (global_start_up) | |
2053 | hash_enable = false; | |
2054 | global_start_up++; | |
2055 | } | |
2056 | ||
ed926f9b | 2057 | ops->flags |= FTRACE_OPS_FL_ENABLED; |
b848914c | 2058 | if (hash_enable) |
ed926f9b SR |
2059 | ftrace_hash_rec_enable(ops, 1); |
2060 | ||
df4fc315 | 2061 | ftrace_startup_enable(command); |
a1cd6173 SR |
2062 | |
2063 | return 0; | |
3d083395 SR |
2064 | } |
2065 | ||
bd69c30b | 2066 | static void ftrace_shutdown(struct ftrace_ops *ops, int command) |
3d083395 | 2067 | { |
b848914c SR |
2068 | bool hash_disable = true; |
2069 | ||
4eebcc81 SR |
2070 | if (unlikely(ftrace_disabled)) |
2071 | return; | |
2072 | ||
60a7ecf4 | 2073 | ftrace_start_up--; |
9ea1a153 FW |
2074 | /* |
2075 | * Just warn in case of unbalance, no need to kill ftrace, it's not | |
2076 | * critical but the ftrace_call callers may be never nopped again after | |
2077 | * further ftrace uses. | |
2078 | */ | |
2079 | WARN_ON_ONCE(ftrace_start_up < 0); | |
2080 | ||
b848914c SR |
2081 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
2082 | ops = &global_ops; | |
2083 | global_start_up--; | |
2084 | WARN_ON_ONCE(global_start_up < 0); | |
2085 | /* Don't update hash if global still has users */ | |
2086 | if (global_start_up) { | |
2087 | WARN_ON_ONCE(!ftrace_start_up); | |
2088 | hash_disable = false; | |
2089 | } | |
2090 | } | |
2091 | ||
2092 | if (hash_disable) | |
ed926f9b SR |
2093 | ftrace_hash_rec_disable(ops, 1); |
2094 | ||
b848914c | 2095 | if (ops != &global_ops || !global_start_up) |
ed926f9b | 2096 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; |
b848914c | 2097 | |
30fb6aa7 | 2098 | command |= FTRACE_UPDATE_CALLS; |
3d083395 | 2099 | |
d61f82d0 SR |
2100 | if (saved_ftrace_func != ftrace_trace_function) { |
2101 | saved_ftrace_func = ftrace_trace_function; | |
2102 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2103 | } | |
3d083395 | 2104 | |
d61f82d0 | 2105 | if (!command || !ftrace_enabled) |
e6ea44e9 | 2106 | return; |
d61f82d0 SR |
2107 | |
2108 | ftrace_run_update_code(command); | |
3d083395 SR |
2109 | } |
2110 | ||
e309b41d | 2111 | static void ftrace_startup_sysctl(void) |
b0fc494f | 2112 | { |
4eebcc81 SR |
2113 | if (unlikely(ftrace_disabled)) |
2114 | return; | |
2115 | ||
d61f82d0 SR |
2116 | /* Force update next time */ |
2117 | saved_ftrace_func = NULL; | |
60a7ecf4 SR |
2118 | /* ftrace_start_up is true if we want ftrace running */ |
2119 | if (ftrace_start_up) | |
30fb6aa7 | 2120 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); |
b0fc494f SR |
2121 | } |
2122 | ||
e309b41d | 2123 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 2124 | { |
4eebcc81 SR |
2125 | if (unlikely(ftrace_disabled)) |
2126 | return; | |
2127 | ||
60a7ecf4 SR |
2128 | /* ftrace_start_up is true if ftrace is running */ |
2129 | if (ftrace_start_up) | |
79e406d7 | 2130 | ftrace_run_update_code(FTRACE_DISABLE_CALLS); |
b0fc494f SR |
2131 | } |
2132 | ||
3d083395 SR |
2133 | static cycle_t ftrace_update_time; |
2134 | static unsigned long ftrace_update_cnt; | |
2135 | unsigned long ftrace_update_tot_cnt; | |
2136 | ||
f7bc8b61 SR |
2137 | static int ops_traces_mod(struct ftrace_ops *ops) |
2138 | { | |
2139 | struct ftrace_hash *hash; | |
2140 | ||
2141 | hash = ops->filter_hash; | |
06a51d93 | 2142 | return ftrace_hash_empty(hash); |
f7bc8b61 SR |
2143 | } |
2144 | ||
31e88909 | 2145 | static int ftrace_update_code(struct module *mod) |
3d083395 | 2146 | { |
85ae32ae | 2147 | struct ftrace_page *pg; |
e94142a6 | 2148 | struct dyn_ftrace *p; |
f22f9a89 | 2149 | cycle_t start, stop; |
f7bc8b61 | 2150 | unsigned long ref = 0; |
85ae32ae | 2151 | int i; |
f7bc8b61 SR |
2152 | |
2153 | /* | |
2154 | * When adding a module, we need to check if tracers are | |
2155 | * currently enabled and if they are set to trace all functions. | |
2156 | * If they are, we need to enable the module functions as well | |
2157 | * as update the reference counts for those function records. | |
2158 | */ | |
2159 | if (mod) { | |
2160 | struct ftrace_ops *ops; | |
2161 | ||
2162 | for (ops = ftrace_ops_list; | |
2163 | ops != &ftrace_list_end; ops = ops->next) { | |
2164 | if (ops->flags & FTRACE_OPS_FL_ENABLED && | |
2165 | ops_traces_mod(ops)) | |
2166 | ref++; | |
2167 | } | |
2168 | } | |
3d083395 | 2169 | |
750ed1a4 | 2170 | start = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
2171 | ftrace_update_cnt = 0; |
2172 | ||
85ae32ae | 2173 | for (pg = ftrace_new_pgs; pg; pg = pg->next) { |
3d083395 | 2174 | |
85ae32ae SR |
2175 | for (i = 0; i < pg->index; i++) { |
2176 | /* If something went wrong, bail without enabling anything */ | |
2177 | if (unlikely(ftrace_disabled)) | |
2178 | return -1; | |
f22f9a89 | 2179 | |
85ae32ae SR |
2180 | p = &pg->records[i]; |
2181 | p->flags = ref; | |
f22f9a89 | 2182 | |
85ae32ae SR |
2183 | /* |
2184 | * Do the initial record conversion from mcount jump | |
2185 | * to the NOP instructions. | |
2186 | */ | |
2187 | if (!ftrace_code_disable(mod, p)) | |
2188 | break; | |
5cb084bb | 2189 | |
85ae32ae | 2190 | ftrace_update_cnt++; |
5cb084bb | 2191 | |
85ae32ae SR |
2192 | /* |
2193 | * If the tracing is enabled, go ahead and enable the record. | |
2194 | * | |
2195 | * The reason not to enable the record immediatelly is the | |
2196 | * inherent check of ftrace_make_nop/ftrace_make_call for | |
2197 | * correct previous instructions. Making first the NOP | |
2198 | * conversion puts the module to the correct state, thus | |
2199 | * passing the ftrace_make_call check. | |
2200 | */ | |
2201 | if (ftrace_start_up && ref) { | |
2202 | int failed = __ftrace_replace_code(p, 1); | |
2203 | if (failed) | |
2204 | ftrace_bug(failed, p->ip); | |
2205 | } | |
5cb084bb | 2206 | } |
3d083395 SR |
2207 | } |
2208 | ||
85ae32ae SR |
2209 | ftrace_new_pgs = NULL; |
2210 | ||
750ed1a4 | 2211 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
2212 | ftrace_update_time = stop - start; |
2213 | ftrace_update_tot_cnt += ftrace_update_cnt; | |
2214 | ||
16444a8a ACM |
2215 | return 0; |
2216 | } | |
2217 | ||
a7900875 | 2218 | static int ftrace_allocate_records(struct ftrace_page *pg, int count) |
3c1720f0 | 2219 | { |
a7900875 | 2220 | int order; |
3c1720f0 | 2221 | int cnt; |
3c1720f0 | 2222 | |
a7900875 SR |
2223 | if (WARN_ON(!count)) |
2224 | return -EINVAL; | |
2225 | ||
2226 | order = get_count_order(DIV_ROUND_UP(count, ENTRIES_PER_PAGE)); | |
3c1720f0 SR |
2227 | |
2228 | /* | |
a7900875 SR |
2229 | * We want to fill as much as possible. No more than a page |
2230 | * may be empty. | |
3c1720f0 | 2231 | */ |
a7900875 SR |
2232 | while ((PAGE_SIZE << order) / ENTRY_SIZE >= count + ENTRIES_PER_PAGE) |
2233 | order--; | |
3c1720f0 | 2234 | |
a7900875 SR |
2235 | again: |
2236 | pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); | |
3c1720f0 | 2237 | |
a7900875 SR |
2238 | if (!pg->records) { |
2239 | /* if we can't allocate this size, try something smaller */ | |
2240 | if (!order) | |
2241 | return -ENOMEM; | |
2242 | order >>= 1; | |
2243 | goto again; | |
2244 | } | |
3c1720f0 | 2245 | |
a7900875 SR |
2246 | cnt = (PAGE_SIZE << order) / ENTRY_SIZE; |
2247 | pg->size = cnt; | |
3c1720f0 | 2248 | |
a7900875 SR |
2249 | if (cnt > count) |
2250 | cnt = count; | |
2251 | ||
2252 | return cnt; | |
2253 | } | |
2254 | ||
2255 | static struct ftrace_page * | |
2256 | ftrace_allocate_pages(unsigned long num_to_init) | |
2257 | { | |
2258 | struct ftrace_page *start_pg; | |
2259 | struct ftrace_page *pg; | |
2260 | int order; | |
2261 | int cnt; | |
2262 | ||
2263 | if (!num_to_init) | |
2264 | return 0; | |
2265 | ||
2266 | start_pg = pg = kzalloc(sizeof(*pg), GFP_KERNEL); | |
2267 | if (!pg) | |
2268 | return NULL; | |
2269 | ||
2270 | /* | |
2271 | * Try to allocate as much as possible in one continues | |
2272 | * location that fills in all of the space. We want to | |
2273 | * waste as little space as possible. | |
2274 | */ | |
2275 | for (;;) { | |
2276 | cnt = ftrace_allocate_records(pg, num_to_init); | |
2277 | if (cnt < 0) | |
2278 | goto free_pages; | |
2279 | ||
2280 | num_to_init -= cnt; | |
2281 | if (!num_to_init) | |
3c1720f0 SR |
2282 | break; |
2283 | ||
a7900875 SR |
2284 | pg->next = kzalloc(sizeof(*pg), GFP_KERNEL); |
2285 | if (!pg->next) | |
2286 | goto free_pages; | |
2287 | ||
3c1720f0 SR |
2288 | pg = pg->next; |
2289 | } | |
2290 | ||
a7900875 SR |
2291 | return start_pg; |
2292 | ||
2293 | free_pages: | |
2294 | while (start_pg) { | |
2295 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); | |
2296 | free_pages((unsigned long)pg->records, order); | |
2297 | start_pg = pg->next; | |
2298 | kfree(pg); | |
2299 | pg = start_pg; | |
2300 | } | |
2301 | pr_info("ftrace: FAILED to allocate memory for functions\n"); | |
2302 | return NULL; | |
2303 | } | |
2304 | ||
2305 | static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) | |
2306 | { | |
2307 | int cnt; | |
2308 | ||
2309 | if (!num_to_init) { | |
2310 | pr_info("ftrace: No functions to be traced?\n"); | |
2311 | return -1; | |
2312 | } | |
2313 | ||
2314 | cnt = num_to_init / ENTRIES_PER_PAGE; | |
2315 | pr_info("ftrace: allocating %ld entries in %d pages\n", | |
2316 | num_to_init, cnt + 1); | |
2317 | ||
3c1720f0 SR |
2318 | return 0; |
2319 | } | |
2320 | ||
5072c59f SR |
2321 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ |
2322 | ||
2323 | struct ftrace_iterator { | |
98c4fd04 | 2324 | loff_t pos; |
4aeb6967 SR |
2325 | loff_t func_pos; |
2326 | struct ftrace_page *pg; | |
2327 | struct dyn_ftrace *func; | |
2328 | struct ftrace_func_probe *probe; | |
2329 | struct trace_parser parser; | |
1cf41dd7 | 2330 | struct ftrace_hash *hash; |
33dc9b12 | 2331 | struct ftrace_ops *ops; |
4aeb6967 SR |
2332 | int hidx; |
2333 | int idx; | |
2334 | unsigned flags; | |
5072c59f SR |
2335 | }; |
2336 | ||
8fc0c701 | 2337 | static void * |
4aeb6967 | 2338 | t_hash_next(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
2339 | { |
2340 | struct ftrace_iterator *iter = m->private; | |
4aeb6967 | 2341 | struct hlist_node *hnd = NULL; |
8fc0c701 SR |
2342 | struct hlist_head *hhd; |
2343 | ||
8fc0c701 | 2344 | (*pos)++; |
98c4fd04 | 2345 | iter->pos = *pos; |
8fc0c701 | 2346 | |
4aeb6967 SR |
2347 | if (iter->probe) |
2348 | hnd = &iter->probe->node; | |
8fc0c701 SR |
2349 | retry: |
2350 | if (iter->hidx >= FTRACE_FUNC_HASHSIZE) | |
2351 | return NULL; | |
2352 | ||
2353 | hhd = &ftrace_func_hash[iter->hidx]; | |
2354 | ||
2355 | if (hlist_empty(hhd)) { | |
2356 | iter->hidx++; | |
2357 | hnd = NULL; | |
2358 | goto retry; | |
2359 | } | |
2360 | ||
2361 | if (!hnd) | |
2362 | hnd = hhd->first; | |
2363 | else { | |
2364 | hnd = hnd->next; | |
2365 | if (!hnd) { | |
2366 | iter->hidx++; | |
2367 | goto retry; | |
2368 | } | |
2369 | } | |
2370 | ||
4aeb6967 SR |
2371 | if (WARN_ON_ONCE(!hnd)) |
2372 | return NULL; | |
2373 | ||
2374 | iter->probe = hlist_entry(hnd, struct ftrace_func_probe, node); | |
2375 | ||
2376 | return iter; | |
8fc0c701 SR |
2377 | } |
2378 | ||
2379 | static void *t_hash_start(struct seq_file *m, loff_t *pos) | |
2380 | { | |
2381 | struct ftrace_iterator *iter = m->private; | |
2382 | void *p = NULL; | |
d82d6244 LZ |
2383 | loff_t l; |
2384 | ||
69a3083c SR |
2385 | if (!(iter->flags & FTRACE_ITER_DO_HASH)) |
2386 | return NULL; | |
2387 | ||
2bccfffd SR |
2388 | if (iter->func_pos > *pos) |
2389 | return NULL; | |
8fc0c701 | 2390 | |
d82d6244 | 2391 | iter->hidx = 0; |
2bccfffd | 2392 | for (l = 0; l <= (*pos - iter->func_pos); ) { |
4aeb6967 | 2393 | p = t_hash_next(m, &l); |
d82d6244 LZ |
2394 | if (!p) |
2395 | break; | |
2396 | } | |
4aeb6967 SR |
2397 | if (!p) |
2398 | return NULL; | |
2399 | ||
98c4fd04 SR |
2400 | /* Only set this if we have an item */ |
2401 | iter->flags |= FTRACE_ITER_HASH; | |
2402 | ||
4aeb6967 | 2403 | return iter; |
8fc0c701 SR |
2404 | } |
2405 | ||
4aeb6967 SR |
2406 | static int |
2407 | t_hash_show(struct seq_file *m, struct ftrace_iterator *iter) | |
8fc0c701 | 2408 | { |
b6887d79 | 2409 | struct ftrace_func_probe *rec; |
8fc0c701 | 2410 | |
4aeb6967 SR |
2411 | rec = iter->probe; |
2412 | if (WARN_ON_ONCE(!rec)) | |
2413 | return -EIO; | |
8fc0c701 | 2414 | |
809dcf29 SR |
2415 | if (rec->ops->print) |
2416 | return rec->ops->print(m, rec->ip, rec->ops, rec->data); | |
2417 | ||
b375a11a | 2418 | seq_printf(m, "%ps:%ps", (void *)rec->ip, (void *)rec->ops->func); |
8fc0c701 SR |
2419 | |
2420 | if (rec->data) | |
2421 | seq_printf(m, ":%p", rec->data); | |
2422 | seq_putc(m, '\n'); | |
2423 | ||
2424 | return 0; | |
2425 | } | |
2426 | ||
e309b41d | 2427 | static void * |
5072c59f SR |
2428 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2429 | { | |
2430 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 2431 | struct ftrace_ops *ops = iter->ops; |
5072c59f SR |
2432 | struct dyn_ftrace *rec = NULL; |
2433 | ||
45a4a237 SR |
2434 | if (unlikely(ftrace_disabled)) |
2435 | return NULL; | |
2436 | ||
8fc0c701 | 2437 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 2438 | return t_hash_next(m, pos); |
8fc0c701 | 2439 | |
5072c59f | 2440 | (*pos)++; |
1106b699 | 2441 | iter->pos = iter->func_pos = *pos; |
5072c59f | 2442 | |
0c75a3ed | 2443 | if (iter->flags & FTRACE_ITER_PRINTALL) |
57c072c7 | 2444 | return t_hash_start(m, pos); |
0c75a3ed | 2445 | |
5072c59f SR |
2446 | retry: |
2447 | if (iter->idx >= iter->pg->index) { | |
2448 | if (iter->pg->next) { | |
2449 | iter->pg = iter->pg->next; | |
2450 | iter->idx = 0; | |
2451 | goto retry; | |
2452 | } | |
2453 | } else { | |
2454 | rec = &iter->pg->records[iter->idx++]; | |
32082309 | 2455 | if (((iter->flags & FTRACE_ITER_FILTER) && |
f45948e8 | 2456 | !(ftrace_lookup_ip(ops->filter_hash, rec->ip))) || |
0183fb1c | 2457 | |
41c52c0d | 2458 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
647bcd03 SR |
2459 | !ftrace_lookup_ip(ops->notrace_hash, rec->ip)) || |
2460 | ||
2461 | ((iter->flags & FTRACE_ITER_ENABLED) && | |
2462 | !(rec->flags & ~FTRACE_FL_MASK))) { | |
2463 | ||
5072c59f SR |
2464 | rec = NULL; |
2465 | goto retry; | |
2466 | } | |
2467 | } | |
2468 | ||
4aeb6967 | 2469 | if (!rec) |
57c072c7 | 2470 | return t_hash_start(m, pos); |
4aeb6967 SR |
2471 | |
2472 | iter->func = rec; | |
2473 | ||
2474 | return iter; | |
5072c59f SR |
2475 | } |
2476 | ||
98c4fd04 SR |
2477 | static void reset_iter_read(struct ftrace_iterator *iter) |
2478 | { | |
2479 | iter->pos = 0; | |
2480 | iter->func_pos = 0; | |
70f77b3f | 2481 | iter->flags &= ~(FTRACE_ITER_PRINTALL | FTRACE_ITER_HASH); |
5072c59f SR |
2482 | } |
2483 | ||
2484 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2485 | { | |
2486 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 2487 | struct ftrace_ops *ops = iter->ops; |
5072c59f | 2488 | void *p = NULL; |
694ce0a5 | 2489 | loff_t l; |
5072c59f | 2490 | |
8fc0c701 | 2491 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
2492 | |
2493 | if (unlikely(ftrace_disabled)) | |
2494 | return NULL; | |
2495 | ||
98c4fd04 SR |
2496 | /* |
2497 | * If an lseek was done, then reset and start from beginning. | |
2498 | */ | |
2499 | if (*pos < iter->pos) | |
2500 | reset_iter_read(iter); | |
2501 | ||
0c75a3ed SR |
2502 | /* |
2503 | * For set_ftrace_filter reading, if we have the filter | |
2504 | * off, we can short cut and just print out that all | |
2505 | * functions are enabled. | |
2506 | */ | |
06a51d93 SR |
2507 | if (iter->flags & FTRACE_ITER_FILTER && |
2508 | ftrace_hash_empty(ops->filter_hash)) { | |
0c75a3ed | 2509 | if (*pos > 0) |
8fc0c701 | 2510 | return t_hash_start(m, pos); |
0c75a3ed | 2511 | iter->flags |= FTRACE_ITER_PRINTALL; |
df091625 CW |
2512 | /* reset in case of seek/pread */ |
2513 | iter->flags &= ~FTRACE_ITER_HASH; | |
0c75a3ed SR |
2514 | return iter; |
2515 | } | |
2516 | ||
8fc0c701 SR |
2517 | if (iter->flags & FTRACE_ITER_HASH) |
2518 | return t_hash_start(m, pos); | |
2519 | ||
98c4fd04 SR |
2520 | /* |
2521 | * Unfortunately, we need to restart at ftrace_pages_start | |
2522 | * every time we let go of the ftrace_mutex. This is because | |
2523 | * those pointers can change without the lock. | |
2524 | */ | |
694ce0a5 LZ |
2525 | iter->pg = ftrace_pages_start; |
2526 | iter->idx = 0; | |
2527 | for (l = 0; l <= *pos; ) { | |
2528 | p = t_next(m, p, &l); | |
2529 | if (!p) | |
2530 | break; | |
50cdaf08 | 2531 | } |
5821e1b7 | 2532 | |
69a3083c SR |
2533 | if (!p) |
2534 | return t_hash_start(m, pos); | |
4aeb6967 SR |
2535 | |
2536 | return iter; | |
5072c59f SR |
2537 | } |
2538 | ||
2539 | static void t_stop(struct seq_file *m, void *p) | |
2540 | { | |
8fc0c701 | 2541 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
2542 | } |
2543 | ||
2544 | static int t_show(struct seq_file *m, void *v) | |
2545 | { | |
0c75a3ed | 2546 | struct ftrace_iterator *iter = m->private; |
4aeb6967 | 2547 | struct dyn_ftrace *rec; |
5072c59f | 2548 | |
8fc0c701 | 2549 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 2550 | return t_hash_show(m, iter); |
8fc0c701 | 2551 | |
0c75a3ed SR |
2552 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
2553 | seq_printf(m, "#### all functions enabled ####\n"); | |
2554 | return 0; | |
2555 | } | |
2556 | ||
4aeb6967 SR |
2557 | rec = iter->func; |
2558 | ||
5072c59f SR |
2559 | if (!rec) |
2560 | return 0; | |
2561 | ||
647bcd03 SR |
2562 | seq_printf(m, "%ps", (void *)rec->ip); |
2563 | if (iter->flags & FTRACE_ITER_ENABLED) | |
08f6fba5 SR |
2564 | seq_printf(m, " (%ld)%s", |
2565 | rec->flags & ~FTRACE_FL_MASK, | |
2566 | rec->flags & FTRACE_FL_REGS ? " R" : ""); | |
647bcd03 | 2567 | seq_printf(m, "\n"); |
5072c59f SR |
2568 | |
2569 | return 0; | |
2570 | } | |
2571 | ||
88e9d34c | 2572 | static const struct seq_operations show_ftrace_seq_ops = { |
5072c59f SR |
2573 | .start = t_start, |
2574 | .next = t_next, | |
2575 | .stop = t_stop, | |
2576 | .show = t_show, | |
2577 | }; | |
2578 | ||
e309b41d | 2579 | static int |
5072c59f SR |
2580 | ftrace_avail_open(struct inode *inode, struct file *file) |
2581 | { | |
2582 | struct ftrace_iterator *iter; | |
5072c59f | 2583 | |
4eebcc81 SR |
2584 | if (unlikely(ftrace_disabled)) |
2585 | return -ENODEV; | |
2586 | ||
50e18b94 JO |
2587 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
2588 | if (iter) { | |
2589 | iter->pg = ftrace_pages_start; | |
2590 | iter->ops = &global_ops; | |
4bf39a94 | 2591 | } |
5072c59f | 2592 | |
50e18b94 | 2593 | return iter ? 0 : -ENOMEM; |
5072c59f SR |
2594 | } |
2595 | ||
647bcd03 SR |
2596 | static int |
2597 | ftrace_enabled_open(struct inode *inode, struct file *file) | |
2598 | { | |
2599 | struct ftrace_iterator *iter; | |
647bcd03 SR |
2600 | |
2601 | if (unlikely(ftrace_disabled)) | |
2602 | return -ENODEV; | |
2603 | ||
50e18b94 JO |
2604 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
2605 | if (iter) { | |
2606 | iter->pg = ftrace_pages_start; | |
2607 | iter->flags = FTRACE_ITER_ENABLED; | |
2608 | iter->ops = &global_ops; | |
647bcd03 SR |
2609 | } |
2610 | ||
50e18b94 | 2611 | return iter ? 0 : -ENOMEM; |
647bcd03 SR |
2612 | } |
2613 | ||
1cf41dd7 | 2614 | static void ftrace_filter_reset(struct ftrace_hash *hash) |
5072c59f | 2615 | { |
52baf119 | 2616 | mutex_lock(&ftrace_lock); |
1cf41dd7 | 2617 | ftrace_hash_clear(hash); |
52baf119 | 2618 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
2619 | } |
2620 | ||
fc13cb0c SR |
2621 | /** |
2622 | * ftrace_regex_open - initialize function tracer filter files | |
2623 | * @ops: The ftrace_ops that hold the hash filters | |
2624 | * @flag: The type of filter to process | |
2625 | * @inode: The inode, usually passed in to your open routine | |
2626 | * @file: The file, usually passed in to your open routine | |
2627 | * | |
2628 | * ftrace_regex_open() initializes the filter files for the | |
2629 | * @ops. Depending on @flag it may process the filter hash or | |
2630 | * the notrace hash of @ops. With this called from the open | |
2631 | * routine, you can use ftrace_filter_write() for the write | |
2632 | * routine if @flag has FTRACE_ITER_FILTER set, or | |
2633 | * ftrace_notrace_write() if @flag has FTRACE_ITER_NOTRACE set. | |
7f49ef69 | 2634 | * ftrace_filter_lseek() should be used as the lseek routine, and |
fc13cb0c SR |
2635 | * release must call ftrace_regex_release(). |
2636 | */ | |
2637 | int | |
f45948e8 | 2638 | ftrace_regex_open(struct ftrace_ops *ops, int flag, |
1cf41dd7 | 2639 | struct inode *inode, struct file *file) |
5072c59f SR |
2640 | { |
2641 | struct ftrace_iterator *iter; | |
f45948e8 | 2642 | struct ftrace_hash *hash; |
5072c59f SR |
2643 | int ret = 0; |
2644 | ||
f04f24fb MH |
2645 | ftrace_ops_init(ops); |
2646 | ||
4eebcc81 SR |
2647 | if (unlikely(ftrace_disabled)) |
2648 | return -ENODEV; | |
2649 | ||
5072c59f SR |
2650 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
2651 | if (!iter) | |
2652 | return -ENOMEM; | |
2653 | ||
689fd8b6 | 2654 | if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) { |
2655 | kfree(iter); | |
2656 | return -ENOMEM; | |
2657 | } | |
2658 | ||
f45948e8 SR |
2659 | if (flag & FTRACE_ITER_NOTRACE) |
2660 | hash = ops->notrace_hash; | |
2661 | else | |
2662 | hash = ops->filter_hash; | |
2663 | ||
33dc9b12 SR |
2664 | iter->ops = ops; |
2665 | iter->flags = flag; | |
2666 | ||
2667 | if (file->f_mode & FMODE_WRITE) { | |
2668 | mutex_lock(&ftrace_lock); | |
2669 | iter->hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash); | |
2670 | mutex_unlock(&ftrace_lock); | |
2671 | ||
2672 | if (!iter->hash) { | |
2673 | trace_parser_put(&iter->parser); | |
2674 | kfree(iter); | |
2675 | return -ENOMEM; | |
2676 | } | |
2677 | } | |
1cf41dd7 | 2678 | |
f04f24fb | 2679 | mutex_lock(&ops->regex_lock); |
33dc9b12 | 2680 | |
5072c59f | 2681 | if ((file->f_mode & FMODE_WRITE) && |
8650ae32 | 2682 | (file->f_flags & O_TRUNC)) |
33dc9b12 | 2683 | ftrace_filter_reset(iter->hash); |
5072c59f SR |
2684 | |
2685 | if (file->f_mode & FMODE_READ) { | |
2686 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
2687 | |
2688 | ret = seq_open(file, &show_ftrace_seq_ops); | |
2689 | if (!ret) { | |
2690 | struct seq_file *m = file->private_data; | |
2691 | m->private = iter; | |
79fe249c | 2692 | } else { |
33dc9b12 SR |
2693 | /* Failed */ |
2694 | free_ftrace_hash(iter->hash); | |
79fe249c | 2695 | trace_parser_put(&iter->parser); |
5072c59f | 2696 | kfree(iter); |
79fe249c | 2697 | } |
5072c59f SR |
2698 | } else |
2699 | file->private_data = iter; | |
f04f24fb | 2700 | mutex_unlock(&ops->regex_lock); |
5072c59f SR |
2701 | |
2702 | return ret; | |
2703 | } | |
2704 | ||
41c52c0d SR |
2705 | static int |
2706 | ftrace_filter_open(struct inode *inode, struct file *file) | |
2707 | { | |
69a3083c SR |
2708 | return ftrace_regex_open(&global_ops, |
2709 | FTRACE_ITER_FILTER | FTRACE_ITER_DO_HASH, | |
2710 | inode, file); | |
41c52c0d SR |
2711 | } |
2712 | ||
2713 | static int | |
2714 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
2715 | { | |
f45948e8 | 2716 | return ftrace_regex_open(&global_ops, FTRACE_ITER_NOTRACE, |
1cf41dd7 | 2717 | inode, file); |
41c52c0d SR |
2718 | } |
2719 | ||
64e7c440 | 2720 | static int ftrace_match(char *str, char *regex, int len, int type) |
9f4801e3 | 2721 | { |
9f4801e3 | 2722 | int matched = 0; |
751e9983 | 2723 | int slen; |
9f4801e3 | 2724 | |
9f4801e3 SR |
2725 | switch (type) { |
2726 | case MATCH_FULL: | |
2727 | if (strcmp(str, regex) == 0) | |
2728 | matched = 1; | |
2729 | break; | |
2730 | case MATCH_FRONT_ONLY: | |
2731 | if (strncmp(str, regex, len) == 0) | |
2732 | matched = 1; | |
2733 | break; | |
2734 | case MATCH_MIDDLE_ONLY: | |
2735 | if (strstr(str, regex)) | |
2736 | matched = 1; | |
2737 | break; | |
2738 | case MATCH_END_ONLY: | |
751e9983 LZ |
2739 | slen = strlen(str); |
2740 | if (slen >= len && memcmp(str + slen - len, regex, len) == 0) | |
9f4801e3 SR |
2741 | matched = 1; |
2742 | break; | |
2743 | } | |
2744 | ||
2745 | return matched; | |
2746 | } | |
2747 | ||
b448c4e3 | 2748 | static int |
1cf41dd7 | 2749 | enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int not) |
996e87be | 2750 | { |
b448c4e3 | 2751 | struct ftrace_func_entry *entry; |
b448c4e3 SR |
2752 | int ret = 0; |
2753 | ||
1cf41dd7 SR |
2754 | entry = ftrace_lookup_ip(hash, rec->ip); |
2755 | if (not) { | |
2756 | /* Do nothing if it doesn't exist */ | |
2757 | if (!entry) | |
2758 | return 0; | |
b448c4e3 | 2759 | |
33dc9b12 | 2760 | free_hash_entry(hash, entry); |
1cf41dd7 SR |
2761 | } else { |
2762 | /* Do nothing if it exists */ | |
2763 | if (entry) | |
2764 | return 0; | |
b448c4e3 | 2765 | |
1cf41dd7 | 2766 | ret = add_hash_entry(hash, rec->ip); |
b448c4e3 SR |
2767 | } |
2768 | return ret; | |
996e87be SR |
2769 | } |
2770 | ||
64e7c440 | 2771 | static int |
b9df92d2 SR |
2772 | ftrace_match_record(struct dyn_ftrace *rec, char *mod, |
2773 | char *regex, int len, int type) | |
64e7c440 SR |
2774 | { |
2775 | char str[KSYM_SYMBOL_LEN]; | |
b9df92d2 SR |
2776 | char *modname; |
2777 | ||
2778 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); | |
2779 | ||
2780 | if (mod) { | |
2781 | /* module lookup requires matching the module */ | |
2782 | if (!modname || strcmp(modname, mod)) | |
2783 | return 0; | |
2784 | ||
2785 | /* blank search means to match all funcs in the mod */ | |
2786 | if (!len) | |
2787 | return 1; | |
2788 | } | |
64e7c440 | 2789 | |
64e7c440 SR |
2790 | return ftrace_match(str, regex, len, type); |
2791 | } | |
2792 | ||
1cf41dd7 SR |
2793 | static int |
2794 | match_records(struct ftrace_hash *hash, char *buff, | |
2795 | int len, char *mod, int not) | |
9f4801e3 | 2796 | { |
b9df92d2 | 2797 | unsigned search_len = 0; |
9f4801e3 SR |
2798 | struct ftrace_page *pg; |
2799 | struct dyn_ftrace *rec; | |
b9df92d2 SR |
2800 | int type = MATCH_FULL; |
2801 | char *search = buff; | |
311d16da | 2802 | int found = 0; |
b448c4e3 | 2803 | int ret; |
9f4801e3 | 2804 | |
b9df92d2 SR |
2805 | if (len) { |
2806 | type = filter_parse_regex(buff, len, &search, ¬); | |
2807 | search_len = strlen(search); | |
2808 | } | |
9f4801e3 | 2809 | |
52baf119 | 2810 | mutex_lock(&ftrace_lock); |
265c831c | 2811 | |
b9df92d2 SR |
2812 | if (unlikely(ftrace_disabled)) |
2813 | goto out_unlock; | |
9f4801e3 | 2814 | |
265c831c | 2815 | do_for_each_ftrace_rec(pg, rec) { |
b9df92d2 | 2816 | if (ftrace_match_record(rec, mod, search, search_len, type)) { |
1cf41dd7 | 2817 | ret = enter_record(hash, rec, not); |
b448c4e3 SR |
2818 | if (ret < 0) { |
2819 | found = ret; | |
2820 | goto out_unlock; | |
2821 | } | |
311d16da | 2822 | found = 1; |
265c831c SR |
2823 | } |
2824 | } while_for_each_ftrace_rec(); | |
b9df92d2 | 2825 | out_unlock: |
52baf119 | 2826 | mutex_unlock(&ftrace_lock); |
311d16da LZ |
2827 | |
2828 | return found; | |
5072c59f SR |
2829 | } |
2830 | ||
64e7c440 | 2831 | static int |
1cf41dd7 | 2832 | ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) |
64e7c440 | 2833 | { |
1cf41dd7 | 2834 | return match_records(hash, buff, len, NULL, 0); |
64e7c440 SR |
2835 | } |
2836 | ||
1cf41dd7 SR |
2837 | static int |
2838 | ftrace_match_module_records(struct ftrace_hash *hash, char *buff, char *mod) | |
64e7c440 | 2839 | { |
64e7c440 | 2840 | int not = 0; |
6a24a244 | 2841 | |
64e7c440 SR |
2842 | /* blank or '*' mean the same */ |
2843 | if (strcmp(buff, "*") == 0) | |
2844 | buff[0] = 0; | |
2845 | ||
2846 | /* handle the case of 'dont filter this module' */ | |
2847 | if (strcmp(buff, "!") == 0 || strcmp(buff, "!*") == 0) { | |
2848 | buff[0] = 0; | |
2849 | not = 1; | |
2850 | } | |
2851 | ||
1cf41dd7 | 2852 | return match_records(hash, buff, strlen(buff), mod, not); |
64e7c440 SR |
2853 | } |
2854 | ||
f6180773 SR |
2855 | /* |
2856 | * We register the module command as a template to show others how | |
2857 | * to register the a command as well. | |
2858 | */ | |
2859 | ||
2860 | static int | |
43dd61c9 SR |
2861 | ftrace_mod_callback(struct ftrace_hash *hash, |
2862 | char *func, char *cmd, char *param, int enable) | |
f6180773 SR |
2863 | { |
2864 | char *mod; | |
b448c4e3 | 2865 | int ret = -EINVAL; |
f6180773 SR |
2866 | |
2867 | /* | |
2868 | * cmd == 'mod' because we only registered this func | |
2869 | * for the 'mod' ftrace_func_command. | |
2870 | * But if you register one func with multiple commands, | |
2871 | * you can tell which command was used by the cmd | |
2872 | * parameter. | |
2873 | */ | |
2874 | ||
2875 | /* we must have a module name */ | |
2876 | if (!param) | |
b448c4e3 | 2877 | return ret; |
f6180773 SR |
2878 | |
2879 | mod = strsep(¶m, ":"); | |
2880 | if (!strlen(mod)) | |
b448c4e3 | 2881 | return ret; |
f6180773 | 2882 | |
1cf41dd7 | 2883 | ret = ftrace_match_module_records(hash, func, mod); |
b448c4e3 SR |
2884 | if (!ret) |
2885 | ret = -EINVAL; | |
2886 | if (ret < 0) | |
2887 | return ret; | |
2888 | ||
2889 | return 0; | |
f6180773 SR |
2890 | } |
2891 | ||
2892 | static struct ftrace_func_command ftrace_mod_cmd = { | |
2893 | .name = "mod", | |
2894 | .func = ftrace_mod_callback, | |
2895 | }; | |
2896 | ||
2897 | static int __init ftrace_mod_cmd_init(void) | |
2898 | { | |
2899 | return register_ftrace_command(&ftrace_mod_cmd); | |
2900 | } | |
6f415672 | 2901 | core_initcall(ftrace_mod_cmd_init); |
f6180773 | 2902 | |
2f5f6ad9 | 2903 | static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 2904 | struct ftrace_ops *op, struct pt_regs *pt_regs) |
59df055f | 2905 | { |
b6887d79 | 2906 | struct ftrace_func_probe *entry; |
59df055f | 2907 | struct hlist_head *hhd; |
59df055f | 2908 | unsigned long key; |
59df055f SR |
2909 | |
2910 | key = hash_long(ip, FTRACE_HASH_BITS); | |
2911 | ||
2912 | hhd = &ftrace_func_hash[key]; | |
2913 | ||
2914 | if (hlist_empty(hhd)) | |
2915 | return; | |
2916 | ||
2917 | /* | |
2918 | * Disable preemption for these calls to prevent a RCU grace | |
2919 | * period. This syncs the hash iteration and freeing of items | |
2920 | * on the hash. rcu_read_lock is too dangerous here. | |
2921 | */ | |
5168ae50 | 2922 | preempt_disable_notrace(); |
b67bfe0d | 2923 | hlist_for_each_entry_rcu(entry, hhd, node) { |
59df055f SR |
2924 | if (entry->ip == ip) |
2925 | entry->ops->func(ip, parent_ip, &entry->data); | |
2926 | } | |
5168ae50 | 2927 | preempt_enable_notrace(); |
59df055f SR |
2928 | } |
2929 | ||
b6887d79 | 2930 | static struct ftrace_ops trace_probe_ops __read_mostly = |
59df055f | 2931 | { |
fb9fb015 | 2932 | .func = function_trace_probe_call, |
f04f24fb MH |
2933 | .flags = FTRACE_OPS_FL_INITIALIZED, |
2934 | INIT_REGEX_LOCK(trace_probe_ops) | |
59df055f SR |
2935 | }; |
2936 | ||
b6887d79 | 2937 | static int ftrace_probe_registered; |
59df055f | 2938 | |
b6887d79 | 2939 | static void __enable_ftrace_function_probe(void) |
59df055f | 2940 | { |
b848914c | 2941 | int ret; |
59df055f SR |
2942 | int i; |
2943 | ||
b6887d79 | 2944 | if (ftrace_probe_registered) |
59df055f SR |
2945 | return; |
2946 | ||
2947 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
2948 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
2949 | if (hhd->first) | |
2950 | break; | |
2951 | } | |
2952 | /* Nothing registered? */ | |
2953 | if (i == FTRACE_FUNC_HASHSIZE) | |
2954 | return; | |
2955 | ||
b848914c SR |
2956 | ret = __register_ftrace_function(&trace_probe_ops); |
2957 | if (!ret) | |
a1cd6173 | 2958 | ret = ftrace_startup(&trace_probe_ops, 0); |
b848914c | 2959 | |
b6887d79 | 2960 | ftrace_probe_registered = 1; |
59df055f SR |
2961 | } |
2962 | ||
b6887d79 | 2963 | static void __disable_ftrace_function_probe(void) |
59df055f | 2964 | { |
b848914c | 2965 | int ret; |
59df055f SR |
2966 | int i; |
2967 | ||
b6887d79 | 2968 | if (!ftrace_probe_registered) |
59df055f SR |
2969 | return; |
2970 | ||
2971 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
2972 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
2973 | if (hhd->first) | |
2974 | return; | |
2975 | } | |
2976 | ||
2977 | /* no more funcs left */ | |
b848914c SR |
2978 | ret = __unregister_ftrace_function(&trace_probe_ops); |
2979 | if (!ret) | |
2980 | ftrace_shutdown(&trace_probe_ops, 0); | |
2981 | ||
b6887d79 | 2982 | ftrace_probe_registered = 0; |
59df055f SR |
2983 | } |
2984 | ||
2985 | ||
7818b388 | 2986 | static void ftrace_free_entry(struct ftrace_func_probe *entry) |
59df055f | 2987 | { |
59df055f | 2988 | if (entry->ops->free) |
e67efb93 | 2989 | entry->ops->free(entry->ops, entry->ip, &entry->data); |
59df055f SR |
2990 | kfree(entry); |
2991 | } | |
2992 | ||
59df055f | 2993 | int |
b6887d79 | 2994 | register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
2995 | void *data) |
2996 | { | |
b6887d79 | 2997 | struct ftrace_func_probe *entry; |
e1df4cb6 SRRH |
2998 | struct ftrace_hash **orig_hash = &trace_probe_ops.filter_hash; |
2999 | struct ftrace_hash *hash; | |
59df055f SR |
3000 | struct ftrace_page *pg; |
3001 | struct dyn_ftrace *rec; | |
59df055f | 3002 | int type, len, not; |
6a24a244 | 3003 | unsigned long key; |
59df055f SR |
3004 | int count = 0; |
3005 | char *search; | |
e1df4cb6 | 3006 | int ret; |
59df055f | 3007 | |
3f6fe06d | 3008 | type = filter_parse_regex(glob, strlen(glob), &search, ¬); |
59df055f SR |
3009 | len = strlen(search); |
3010 | ||
b6887d79 | 3011 | /* we do not support '!' for function probes */ |
59df055f SR |
3012 | if (WARN_ON(not)) |
3013 | return -EINVAL; | |
3014 | ||
3015 | mutex_lock(&ftrace_lock); | |
59df055f | 3016 | |
e1df4cb6 SRRH |
3017 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); |
3018 | if (!hash) { | |
3019 | count = -ENOMEM; | |
45a4a237 | 3020 | goto out_unlock; |
e1df4cb6 SRRH |
3021 | } |
3022 | ||
3023 | if (unlikely(ftrace_disabled)) { | |
3024 | count = -ENODEV; | |
3025 | goto out_unlock; | |
3026 | } | |
59df055f | 3027 | |
45a4a237 | 3028 | do_for_each_ftrace_rec(pg, rec) { |
59df055f | 3029 | |
b9df92d2 | 3030 | if (!ftrace_match_record(rec, NULL, search, len, type)) |
59df055f SR |
3031 | continue; |
3032 | ||
3033 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
3034 | if (!entry) { | |
b6887d79 | 3035 | /* If we did not process any, then return error */ |
59df055f SR |
3036 | if (!count) |
3037 | count = -ENOMEM; | |
3038 | goto out_unlock; | |
3039 | } | |
3040 | ||
3041 | count++; | |
3042 | ||
3043 | entry->data = data; | |
3044 | ||
3045 | /* | |
3046 | * The caller might want to do something special | |
3047 | * for each function we find. We call the callback | |
3048 | * to give the caller an opportunity to do so. | |
3049 | */ | |
e67efb93 SRRH |
3050 | if (ops->init) { |
3051 | if (ops->init(ops, rec->ip, &entry->data) < 0) { | |
59df055f SR |
3052 | /* caller does not like this func */ |
3053 | kfree(entry); | |
3054 | continue; | |
3055 | } | |
3056 | } | |
3057 | ||
e1df4cb6 SRRH |
3058 | ret = enter_record(hash, rec, 0); |
3059 | if (ret < 0) { | |
3060 | kfree(entry); | |
3061 | count = ret; | |
3062 | goto out_unlock; | |
3063 | } | |
3064 | ||
59df055f SR |
3065 | entry->ops = ops; |
3066 | entry->ip = rec->ip; | |
3067 | ||
3068 | key = hash_long(entry->ip, FTRACE_HASH_BITS); | |
3069 | hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]); | |
3070 | ||
3071 | } while_for_each_ftrace_rec(); | |
e1df4cb6 SRRH |
3072 | |
3073 | ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash); | |
3074 | if (ret < 0) | |
3075 | count = ret; | |
3076 | ||
b6887d79 | 3077 | __enable_ftrace_function_probe(); |
59df055f SR |
3078 | |
3079 | out_unlock: | |
3080 | mutex_unlock(&ftrace_lock); | |
e1df4cb6 | 3081 | free_ftrace_hash(hash); |
59df055f SR |
3082 | |
3083 | return count; | |
3084 | } | |
3085 | ||
3086 | enum { | |
b6887d79 SR |
3087 | PROBE_TEST_FUNC = 1, |
3088 | PROBE_TEST_DATA = 2 | |
59df055f SR |
3089 | }; |
3090 | ||
3091 | static void | |
b6887d79 | 3092 | __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3093 | void *data, int flags) |
3094 | { | |
e1df4cb6 | 3095 | struct ftrace_func_entry *rec_entry; |
b6887d79 | 3096 | struct ftrace_func_probe *entry; |
7818b388 | 3097 | struct ftrace_func_probe *p; |
e1df4cb6 | 3098 | struct ftrace_hash **orig_hash = &trace_probe_ops.filter_hash; |
7818b388 | 3099 | struct list_head free_list; |
e1df4cb6 | 3100 | struct ftrace_hash *hash; |
b67bfe0d | 3101 | struct hlist_node *tmp; |
59df055f SR |
3102 | char str[KSYM_SYMBOL_LEN]; |
3103 | int type = MATCH_FULL; | |
3104 | int i, len = 0; | |
3105 | char *search; | |
3106 | ||
b36461da | 3107 | if (glob && (strcmp(glob, "*") == 0 || !strlen(glob))) |
59df055f | 3108 | glob = NULL; |
b36461da | 3109 | else if (glob) { |
59df055f SR |
3110 | int not; |
3111 | ||
3f6fe06d | 3112 | type = filter_parse_regex(glob, strlen(glob), &search, ¬); |
59df055f SR |
3113 | len = strlen(search); |
3114 | ||
b6887d79 | 3115 | /* we do not support '!' for function probes */ |
59df055f SR |
3116 | if (WARN_ON(not)) |
3117 | return; | |
3118 | } | |
3119 | ||
3120 | mutex_lock(&ftrace_lock); | |
e1df4cb6 SRRH |
3121 | |
3122 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
3123 | if (!hash) | |
3124 | /* Hmm, should report this somehow */ | |
3125 | goto out_unlock; | |
3126 | ||
7818b388 SRRH |
3127 | INIT_LIST_HEAD(&free_list); |
3128 | ||
59df055f SR |
3129 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { |
3130 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3131 | ||
b67bfe0d | 3132 | hlist_for_each_entry_safe(entry, tmp, hhd, node) { |
59df055f SR |
3133 | |
3134 | /* break up if statements for readability */ | |
b6887d79 | 3135 | if ((flags & PROBE_TEST_FUNC) && entry->ops != ops) |
59df055f SR |
3136 | continue; |
3137 | ||
b6887d79 | 3138 | if ((flags & PROBE_TEST_DATA) && entry->data != data) |
59df055f SR |
3139 | continue; |
3140 | ||
3141 | /* do this last, since it is the most expensive */ | |
3142 | if (glob) { | |
3143 | kallsyms_lookup(entry->ip, NULL, NULL, | |
3144 | NULL, str); | |
3145 | if (!ftrace_match(str, glob, len, type)) | |
3146 | continue; | |
3147 | } | |
3148 | ||
e1df4cb6 SRRH |
3149 | rec_entry = ftrace_lookup_ip(hash, entry->ip); |
3150 | /* It is possible more than one entry had this ip */ | |
3151 | if (rec_entry) | |
3152 | free_hash_entry(hash, rec_entry); | |
3153 | ||
740466bc | 3154 | hlist_del_rcu(&entry->node); |
7818b388 | 3155 | list_add(&entry->free_list, &free_list); |
59df055f SR |
3156 | } |
3157 | } | |
b6887d79 | 3158 | __disable_ftrace_function_probe(); |
e1df4cb6 SRRH |
3159 | /* |
3160 | * Remove after the disable is called. Otherwise, if the last | |
3161 | * probe is removed, a null hash means *all enabled*. | |
3162 | */ | |
3163 | ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash); | |
7818b388 SRRH |
3164 | synchronize_sched(); |
3165 | list_for_each_entry_safe(entry, p, &free_list, free_list) { | |
3166 | list_del(&entry->free_list); | |
3167 | ftrace_free_entry(entry); | |
3168 | } | |
3169 | ||
e1df4cb6 | 3170 | out_unlock: |
59df055f | 3171 | mutex_unlock(&ftrace_lock); |
e1df4cb6 | 3172 | free_ftrace_hash(hash); |
59df055f SR |
3173 | } |
3174 | ||
3175 | void | |
b6887d79 | 3176 | unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3177 | void *data) |
3178 | { | |
b6887d79 SR |
3179 | __unregister_ftrace_function_probe(glob, ops, data, |
3180 | PROBE_TEST_FUNC | PROBE_TEST_DATA); | |
59df055f SR |
3181 | } |
3182 | ||
3183 | void | |
b6887d79 | 3184 | unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops) |
59df055f | 3185 | { |
b6887d79 | 3186 | __unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC); |
59df055f SR |
3187 | } |
3188 | ||
b6887d79 | 3189 | void unregister_ftrace_function_probe_all(char *glob) |
59df055f | 3190 | { |
b6887d79 | 3191 | __unregister_ftrace_function_probe(glob, NULL, NULL, 0); |
59df055f SR |
3192 | } |
3193 | ||
f6180773 SR |
3194 | static LIST_HEAD(ftrace_commands); |
3195 | static DEFINE_MUTEX(ftrace_cmd_mutex); | |
3196 | ||
3197 | int register_ftrace_command(struct ftrace_func_command *cmd) | |
3198 | { | |
3199 | struct ftrace_func_command *p; | |
3200 | int ret = 0; | |
3201 | ||
3202 | mutex_lock(&ftrace_cmd_mutex); | |
3203 | list_for_each_entry(p, &ftrace_commands, list) { | |
3204 | if (strcmp(cmd->name, p->name) == 0) { | |
3205 | ret = -EBUSY; | |
3206 | goto out_unlock; | |
3207 | } | |
3208 | } | |
3209 | list_add(&cmd->list, &ftrace_commands); | |
3210 | out_unlock: | |
3211 | mutex_unlock(&ftrace_cmd_mutex); | |
3212 | ||
3213 | return ret; | |
3214 | } | |
3215 | ||
3216 | int unregister_ftrace_command(struct ftrace_func_command *cmd) | |
3217 | { | |
3218 | struct ftrace_func_command *p, *n; | |
3219 | int ret = -ENODEV; | |
3220 | ||
3221 | mutex_lock(&ftrace_cmd_mutex); | |
3222 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { | |
3223 | if (strcmp(cmd->name, p->name) == 0) { | |
3224 | ret = 0; | |
3225 | list_del_init(&p->list); | |
3226 | goto out_unlock; | |
3227 | } | |
3228 | } | |
3229 | out_unlock: | |
3230 | mutex_unlock(&ftrace_cmd_mutex); | |
3231 | ||
3232 | return ret; | |
3233 | } | |
3234 | ||
33dc9b12 SR |
3235 | static int ftrace_process_regex(struct ftrace_hash *hash, |
3236 | char *buff, int len, int enable) | |
64e7c440 | 3237 | { |
f6180773 | 3238 | char *func, *command, *next = buff; |
6a24a244 | 3239 | struct ftrace_func_command *p; |
0aff1c0c | 3240 | int ret = -EINVAL; |
64e7c440 SR |
3241 | |
3242 | func = strsep(&next, ":"); | |
3243 | ||
3244 | if (!next) { | |
1cf41dd7 | 3245 | ret = ftrace_match_records(hash, func, len); |
b448c4e3 SR |
3246 | if (!ret) |
3247 | ret = -EINVAL; | |
3248 | if (ret < 0) | |
3249 | return ret; | |
3250 | return 0; | |
64e7c440 SR |
3251 | } |
3252 | ||
f6180773 | 3253 | /* command found */ |
64e7c440 SR |
3254 | |
3255 | command = strsep(&next, ":"); | |
3256 | ||
f6180773 SR |
3257 | mutex_lock(&ftrace_cmd_mutex); |
3258 | list_for_each_entry(p, &ftrace_commands, list) { | |
3259 | if (strcmp(p->name, command) == 0) { | |
43dd61c9 | 3260 | ret = p->func(hash, func, command, next, enable); |
f6180773 SR |
3261 | goto out_unlock; |
3262 | } | |
64e7c440 | 3263 | } |
f6180773 SR |
3264 | out_unlock: |
3265 | mutex_unlock(&ftrace_cmd_mutex); | |
64e7c440 | 3266 | |
f6180773 | 3267 | return ret; |
64e7c440 SR |
3268 | } |
3269 | ||
e309b41d | 3270 | static ssize_t |
41c52c0d SR |
3271 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
3272 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
3273 | { |
3274 | struct ftrace_iterator *iter; | |
689fd8b6 | 3275 | struct trace_parser *parser; |
3276 | ssize_t ret, read; | |
5072c59f | 3277 | |
4ba7978e | 3278 | if (!cnt) |
5072c59f SR |
3279 | return 0; |
3280 | ||
5072c59f SR |
3281 | if (file->f_mode & FMODE_READ) { |
3282 | struct seq_file *m = file->private_data; | |
3283 | iter = m->private; | |
3284 | } else | |
3285 | iter = file->private_data; | |
3286 | ||
f04f24fb MH |
3287 | mutex_lock(&iter->ops->regex_lock); |
3288 | ||
3289 | ret = -ENODEV; | |
3290 | if (unlikely(ftrace_disabled)) | |
3291 | goto out_unlock; | |
3292 | ||
689fd8b6 | 3293 | parser = &iter->parser; |
3294 | read = trace_get_user(parser, ubuf, cnt, ppos); | |
5072c59f | 3295 | |
4ba7978e | 3296 | if (read >= 0 && trace_parser_loaded(parser) && |
689fd8b6 | 3297 | !trace_parser_cont(parser)) { |
33dc9b12 | 3298 | ret = ftrace_process_regex(iter->hash, parser->buffer, |
689fd8b6 | 3299 | parser->idx, enable); |
313254a9 | 3300 | trace_parser_clear(parser); |
7c088b51 | 3301 | if (ret < 0) |
ed146b25 | 3302 | goto out_unlock; |
eda1e328 | 3303 | } |
5072c59f | 3304 | |
5072c59f | 3305 | ret = read; |
ed146b25 | 3306 | out_unlock: |
f04f24fb | 3307 | mutex_unlock(&iter->ops->regex_lock); |
ed146b25 | 3308 | |
5072c59f SR |
3309 | return ret; |
3310 | } | |
3311 | ||
fc13cb0c | 3312 | ssize_t |
41c52c0d SR |
3313 | ftrace_filter_write(struct file *file, const char __user *ubuf, |
3314 | size_t cnt, loff_t *ppos) | |
3315 | { | |
3316 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
3317 | } | |
3318 | ||
fc13cb0c | 3319 | ssize_t |
41c52c0d SR |
3320 | ftrace_notrace_write(struct file *file, const char __user *ubuf, |
3321 | size_t cnt, loff_t *ppos) | |
3322 | { | |
3323 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
3324 | } | |
3325 | ||
33dc9b12 | 3326 | static int |
647664ea MH |
3327 | ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) |
3328 | { | |
3329 | struct ftrace_func_entry *entry; | |
3330 | ||
3331 | if (!ftrace_location(ip)) | |
3332 | return -EINVAL; | |
3333 | ||
3334 | if (remove) { | |
3335 | entry = ftrace_lookup_ip(hash, ip); | |
3336 | if (!entry) | |
3337 | return -ENOENT; | |
3338 | free_hash_entry(hash, entry); | |
3339 | return 0; | |
3340 | } | |
3341 | ||
3342 | return add_hash_entry(hash, ip); | |
3343 | } | |
3344 | ||
3345 | static int | |
3346 | ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, | |
3347 | unsigned long ip, int remove, int reset, int enable) | |
41c52c0d | 3348 | { |
33dc9b12 | 3349 | struct ftrace_hash **orig_hash; |
f45948e8 | 3350 | struct ftrace_hash *hash; |
33dc9b12 | 3351 | int ret; |
f45948e8 | 3352 | |
936e074b SR |
3353 | /* All global ops uses the global ops filters */ |
3354 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) | |
3355 | ops = &global_ops; | |
3356 | ||
41c52c0d | 3357 | if (unlikely(ftrace_disabled)) |
33dc9b12 | 3358 | return -ENODEV; |
41c52c0d | 3359 | |
f45948e8 | 3360 | if (enable) |
33dc9b12 | 3361 | orig_hash = &ops->filter_hash; |
f45948e8 | 3362 | else |
33dc9b12 SR |
3363 | orig_hash = &ops->notrace_hash; |
3364 | ||
3365 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
3366 | if (!hash) | |
3367 | return -ENOMEM; | |
f45948e8 | 3368 | |
f04f24fb | 3369 | mutex_lock(&ops->regex_lock); |
41c52c0d | 3370 | if (reset) |
1cf41dd7 | 3371 | ftrace_filter_reset(hash); |
ac483c44 JO |
3372 | if (buf && !ftrace_match_records(hash, buf, len)) { |
3373 | ret = -EINVAL; | |
3374 | goto out_regex_unlock; | |
3375 | } | |
647664ea MH |
3376 | if (ip) { |
3377 | ret = ftrace_match_addr(hash, ip, remove); | |
3378 | if (ret < 0) | |
3379 | goto out_regex_unlock; | |
3380 | } | |
33dc9b12 SR |
3381 | |
3382 | mutex_lock(&ftrace_lock); | |
41fb61c2 | 3383 | ret = ftrace_hash_move(ops, enable, orig_hash, hash); |
072126f4 SR |
3384 | if (!ret && ops->flags & FTRACE_OPS_FL_ENABLED |
3385 | && ftrace_enabled) | |
30fb6aa7 | 3386 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); |
072126f4 | 3387 | |
33dc9b12 SR |
3388 | mutex_unlock(&ftrace_lock); |
3389 | ||
ac483c44 | 3390 | out_regex_unlock: |
f04f24fb | 3391 | mutex_unlock(&ops->regex_lock); |
33dc9b12 SR |
3392 | |
3393 | free_ftrace_hash(hash); | |
3394 | return ret; | |
41c52c0d SR |
3395 | } |
3396 | ||
647664ea MH |
3397 | static int |
3398 | ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove, | |
3399 | int reset, int enable) | |
3400 | { | |
3401 | return ftrace_set_hash(ops, 0, 0, ip, remove, reset, enable); | |
3402 | } | |
3403 | ||
3404 | /** | |
3405 | * ftrace_set_filter_ip - set a function to filter on in ftrace by address | |
3406 | * @ops - the ops to set the filter with | |
3407 | * @ip - the address to add to or remove from the filter. | |
3408 | * @remove - non zero to remove the ip from the filter | |
3409 | * @reset - non zero to reset all filters before applying this filter. | |
3410 | * | |
3411 | * Filters denote which functions should be enabled when tracing is enabled | |
3412 | * If @ip is NULL, it failes to update filter. | |
3413 | */ | |
3414 | int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, | |
3415 | int remove, int reset) | |
3416 | { | |
f04f24fb | 3417 | ftrace_ops_init(ops); |
647664ea MH |
3418 | return ftrace_set_addr(ops, ip, remove, reset, 1); |
3419 | } | |
3420 | EXPORT_SYMBOL_GPL(ftrace_set_filter_ip); | |
3421 | ||
3422 | static int | |
3423 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, | |
3424 | int reset, int enable) | |
3425 | { | |
3426 | return ftrace_set_hash(ops, buf, len, 0, 0, reset, enable); | |
3427 | } | |
3428 | ||
77a2b37d SR |
3429 | /** |
3430 | * ftrace_set_filter - set a function to filter on in ftrace | |
936e074b SR |
3431 | * @ops - the ops to set the filter with |
3432 | * @buf - the string that holds the function filter text. | |
3433 | * @len - the length of the string. | |
3434 | * @reset - non zero to reset all filters before applying this filter. | |
3435 | * | |
3436 | * Filters denote which functions should be enabled when tracing is enabled. | |
3437 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
3438 | */ | |
ac483c44 | 3439 | int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
3440 | int len, int reset) |
3441 | { | |
f04f24fb | 3442 | ftrace_ops_init(ops); |
ac483c44 | 3443 | return ftrace_set_regex(ops, buf, len, reset, 1); |
936e074b SR |
3444 | } |
3445 | EXPORT_SYMBOL_GPL(ftrace_set_filter); | |
3446 | ||
3447 | /** | |
3448 | * ftrace_set_notrace - set a function to not trace in ftrace | |
3449 | * @ops - the ops to set the notrace filter with | |
3450 | * @buf - the string that holds the function notrace text. | |
3451 | * @len - the length of the string. | |
3452 | * @reset - non zero to reset all filters before applying this filter. | |
3453 | * | |
3454 | * Notrace Filters denote which functions should not be enabled when tracing | |
3455 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
3456 | * for tracing. | |
3457 | */ | |
ac483c44 | 3458 | int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
3459 | int len, int reset) |
3460 | { | |
f04f24fb | 3461 | ftrace_ops_init(ops); |
ac483c44 | 3462 | return ftrace_set_regex(ops, buf, len, reset, 0); |
936e074b SR |
3463 | } |
3464 | EXPORT_SYMBOL_GPL(ftrace_set_notrace); | |
3465 | /** | |
3466 | * ftrace_set_filter - set a function to filter on in ftrace | |
3467 | * @ops - the ops to set the filter with | |
77a2b37d SR |
3468 | * @buf - the string that holds the function filter text. |
3469 | * @len - the length of the string. | |
3470 | * @reset - non zero to reset all filters before applying this filter. | |
3471 | * | |
3472 | * Filters denote which functions should be enabled when tracing is enabled. | |
3473 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
3474 | */ | |
936e074b | 3475 | void ftrace_set_global_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 3476 | { |
f45948e8 | 3477 | ftrace_set_regex(&global_ops, buf, len, reset, 1); |
41c52c0d | 3478 | } |
936e074b | 3479 | EXPORT_SYMBOL_GPL(ftrace_set_global_filter); |
4eebcc81 | 3480 | |
41c52c0d SR |
3481 | /** |
3482 | * ftrace_set_notrace - set a function to not trace in ftrace | |
936e074b | 3483 | * @ops - the ops to set the notrace filter with |
41c52c0d SR |
3484 | * @buf - the string that holds the function notrace text. |
3485 | * @len - the length of the string. | |
3486 | * @reset - non zero to reset all filters before applying this filter. | |
3487 | * | |
3488 | * Notrace Filters denote which functions should not be enabled when tracing | |
3489 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
3490 | * for tracing. | |
3491 | */ | |
936e074b | 3492 | void ftrace_set_global_notrace(unsigned char *buf, int len, int reset) |
41c52c0d | 3493 | { |
f45948e8 | 3494 | ftrace_set_regex(&global_ops, buf, len, reset, 0); |
77a2b37d | 3495 | } |
936e074b | 3496 | EXPORT_SYMBOL_GPL(ftrace_set_global_notrace); |
77a2b37d | 3497 | |
2af15d6a SR |
3498 | /* |
3499 | * command line interface to allow users to set filters on boot up. | |
3500 | */ | |
3501 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE | |
3502 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; | |
3503 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; | |
3504 | ||
3505 | static int __init set_ftrace_notrace(char *str) | |
3506 | { | |
75761cc1 | 3507 | strlcpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
3508 | return 1; |
3509 | } | |
3510 | __setup("ftrace_notrace=", set_ftrace_notrace); | |
3511 | ||
3512 | static int __init set_ftrace_filter(char *str) | |
3513 | { | |
75761cc1 | 3514 | strlcpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
3515 | return 1; |
3516 | } | |
3517 | __setup("ftrace_filter=", set_ftrace_filter); | |
3518 | ||
369bc18f | 3519 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
f6060f46 | 3520 | static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; |
801c29fd SR |
3521 | static int ftrace_set_func(unsigned long *array, int *idx, char *buffer); |
3522 | ||
369bc18f SA |
3523 | static int __init set_graph_function(char *str) |
3524 | { | |
06f43d66 | 3525 | strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); |
369bc18f SA |
3526 | return 1; |
3527 | } | |
3528 | __setup("ftrace_graph_filter=", set_graph_function); | |
3529 | ||
3530 | static void __init set_ftrace_early_graph(char *buf) | |
3531 | { | |
3532 | int ret; | |
3533 | char *func; | |
3534 | ||
3535 | while (buf) { | |
3536 | func = strsep(&buf, ","); | |
3537 | /* we allow only one expression at a time */ | |
3538 | ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, | |
3539 | func); | |
3540 | if (ret) | |
3541 | printk(KERN_DEBUG "ftrace: function %s not " | |
3542 | "traceable\n", func); | |
3543 | } | |
3544 | } | |
3545 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
3546 | ||
2a85a37f SR |
3547 | void __init |
3548 | ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable) | |
2af15d6a SR |
3549 | { |
3550 | char *func; | |
3551 | ||
f04f24fb MH |
3552 | ftrace_ops_init(ops); |
3553 | ||
2af15d6a SR |
3554 | while (buf) { |
3555 | func = strsep(&buf, ","); | |
f45948e8 | 3556 | ftrace_set_regex(ops, func, strlen(func), 0, enable); |
2af15d6a SR |
3557 | } |
3558 | } | |
3559 | ||
3560 | static void __init set_ftrace_early_filters(void) | |
3561 | { | |
3562 | if (ftrace_filter_buf[0]) | |
2a85a37f | 3563 | ftrace_set_early_filter(&global_ops, ftrace_filter_buf, 1); |
2af15d6a | 3564 | if (ftrace_notrace_buf[0]) |
2a85a37f | 3565 | ftrace_set_early_filter(&global_ops, ftrace_notrace_buf, 0); |
369bc18f SA |
3566 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
3567 | if (ftrace_graph_buf[0]) | |
3568 | set_ftrace_early_graph(ftrace_graph_buf); | |
3569 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
2af15d6a SR |
3570 | } |
3571 | ||
fc13cb0c | 3572 | int ftrace_regex_release(struct inode *inode, struct file *file) |
5072c59f SR |
3573 | { |
3574 | struct seq_file *m = (struct seq_file *)file->private_data; | |
3575 | struct ftrace_iterator *iter; | |
33dc9b12 | 3576 | struct ftrace_hash **orig_hash; |
689fd8b6 | 3577 | struct trace_parser *parser; |
ed926f9b | 3578 | int filter_hash; |
33dc9b12 | 3579 | int ret; |
5072c59f | 3580 | |
5072c59f SR |
3581 | if (file->f_mode & FMODE_READ) { |
3582 | iter = m->private; | |
5072c59f SR |
3583 | seq_release(inode, file); |
3584 | } else | |
3585 | iter = file->private_data; | |
3586 | ||
f04f24fb MH |
3587 | mutex_lock(&iter->ops->regex_lock); |
3588 | ||
689fd8b6 | 3589 | parser = &iter->parser; |
3590 | if (trace_parser_loaded(parser)) { | |
3591 | parser->buffer[parser->idx] = 0; | |
1cf41dd7 | 3592 | ftrace_match_records(iter->hash, parser->buffer, parser->idx); |
5072c59f SR |
3593 | } |
3594 | ||
689fd8b6 | 3595 | trace_parser_put(parser); |
689fd8b6 | 3596 | |
058e297d | 3597 | if (file->f_mode & FMODE_WRITE) { |
ed926f9b SR |
3598 | filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); |
3599 | ||
3600 | if (filter_hash) | |
33dc9b12 | 3601 | orig_hash = &iter->ops->filter_hash; |
ed926f9b SR |
3602 | else |
3603 | orig_hash = &iter->ops->notrace_hash; | |
33dc9b12 | 3604 | |
058e297d | 3605 | mutex_lock(&ftrace_lock); |
41fb61c2 SR |
3606 | ret = ftrace_hash_move(iter->ops, filter_hash, |
3607 | orig_hash, iter->hash); | |
3608 | if (!ret && (iter->ops->flags & FTRACE_OPS_FL_ENABLED) | |
3609 | && ftrace_enabled) | |
30fb6aa7 | 3610 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); |
41fb61c2 | 3611 | |
058e297d SR |
3612 | mutex_unlock(&ftrace_lock); |
3613 | } | |
33dc9b12 SR |
3614 | free_ftrace_hash(iter->hash); |
3615 | kfree(iter); | |
058e297d | 3616 | |
f04f24fb | 3617 | mutex_unlock(&iter->ops->regex_lock); |
5072c59f SR |
3618 | return 0; |
3619 | } | |
3620 | ||
5e2336a0 | 3621 | static const struct file_operations ftrace_avail_fops = { |
5072c59f SR |
3622 | .open = ftrace_avail_open, |
3623 | .read = seq_read, | |
3624 | .llseek = seq_lseek, | |
3be04b47 | 3625 | .release = seq_release_private, |
5072c59f SR |
3626 | }; |
3627 | ||
647bcd03 SR |
3628 | static const struct file_operations ftrace_enabled_fops = { |
3629 | .open = ftrace_enabled_open, | |
3630 | .read = seq_read, | |
3631 | .llseek = seq_lseek, | |
3632 | .release = seq_release_private, | |
3633 | }; | |
3634 | ||
5e2336a0 | 3635 | static const struct file_operations ftrace_filter_fops = { |
5072c59f | 3636 | .open = ftrace_filter_open, |
850a80cf | 3637 | .read = seq_read, |
5072c59f | 3638 | .write = ftrace_filter_write, |
6a76f8c0 | 3639 | .llseek = ftrace_filter_lseek, |
1cf41dd7 | 3640 | .release = ftrace_regex_release, |
5072c59f SR |
3641 | }; |
3642 | ||
5e2336a0 | 3643 | static const struct file_operations ftrace_notrace_fops = { |
41c52c0d | 3644 | .open = ftrace_notrace_open, |
850a80cf | 3645 | .read = seq_read, |
41c52c0d | 3646 | .write = ftrace_notrace_write, |
6a76f8c0 | 3647 | .llseek = ftrace_filter_lseek, |
1cf41dd7 | 3648 | .release = ftrace_regex_release, |
41c52c0d SR |
3649 | }; |
3650 | ||
ea4e2bc4 SR |
3651 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
3652 | ||
3653 | static DEFINE_MUTEX(graph_lock); | |
3654 | ||
3655 | int ftrace_graph_count; | |
c7c6b1fe | 3656 | int ftrace_graph_filter_enabled; |
ea4e2bc4 SR |
3657 | unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; |
3658 | ||
3659 | static void * | |
85951842 | 3660 | __g_next(struct seq_file *m, loff_t *pos) |
ea4e2bc4 | 3661 | { |
85951842 | 3662 | if (*pos >= ftrace_graph_count) |
ea4e2bc4 | 3663 | return NULL; |
a4ec5e0c | 3664 | return &ftrace_graph_funcs[*pos]; |
85951842 | 3665 | } |
ea4e2bc4 | 3666 | |
85951842 LZ |
3667 | static void * |
3668 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
3669 | { | |
3670 | (*pos)++; | |
3671 | return __g_next(m, pos); | |
ea4e2bc4 SR |
3672 | } |
3673 | ||
3674 | static void *g_start(struct seq_file *m, loff_t *pos) | |
3675 | { | |
ea4e2bc4 SR |
3676 | mutex_lock(&graph_lock); |
3677 | ||
f9349a8f | 3678 | /* Nothing, tell g_show to print all functions are enabled */ |
c7c6b1fe | 3679 | if (!ftrace_graph_filter_enabled && !*pos) |
f9349a8f FW |
3680 | return (void *)1; |
3681 | ||
85951842 | 3682 | return __g_next(m, pos); |
ea4e2bc4 SR |
3683 | } |
3684 | ||
3685 | static void g_stop(struct seq_file *m, void *p) | |
3686 | { | |
3687 | mutex_unlock(&graph_lock); | |
3688 | } | |
3689 | ||
3690 | static int g_show(struct seq_file *m, void *v) | |
3691 | { | |
3692 | unsigned long *ptr = v; | |
ea4e2bc4 SR |
3693 | |
3694 | if (!ptr) | |
3695 | return 0; | |
3696 | ||
f9349a8f FW |
3697 | if (ptr == (unsigned long *)1) { |
3698 | seq_printf(m, "#### all functions enabled ####\n"); | |
3699 | return 0; | |
3700 | } | |
3701 | ||
b375a11a | 3702 | seq_printf(m, "%ps\n", (void *)*ptr); |
ea4e2bc4 SR |
3703 | |
3704 | return 0; | |
3705 | } | |
3706 | ||
88e9d34c | 3707 | static const struct seq_operations ftrace_graph_seq_ops = { |
ea4e2bc4 SR |
3708 | .start = g_start, |
3709 | .next = g_next, | |
3710 | .stop = g_stop, | |
3711 | .show = g_show, | |
3712 | }; | |
3713 | ||
3714 | static int | |
3715 | ftrace_graph_open(struct inode *inode, struct file *file) | |
3716 | { | |
3717 | int ret = 0; | |
3718 | ||
3719 | if (unlikely(ftrace_disabled)) | |
3720 | return -ENODEV; | |
3721 | ||
3722 | mutex_lock(&graph_lock); | |
3723 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 3724 | (file->f_flags & O_TRUNC)) { |
c7c6b1fe | 3725 | ftrace_graph_filter_enabled = 0; |
ea4e2bc4 SR |
3726 | ftrace_graph_count = 0; |
3727 | memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); | |
3728 | } | |
a4ec5e0c | 3729 | mutex_unlock(&graph_lock); |
ea4e2bc4 | 3730 | |
a4ec5e0c | 3731 | if (file->f_mode & FMODE_READ) |
ea4e2bc4 | 3732 | ret = seq_open(file, &ftrace_graph_seq_ops); |
ea4e2bc4 SR |
3733 | |
3734 | return ret; | |
3735 | } | |
3736 | ||
87827111 LZ |
3737 | static int |
3738 | ftrace_graph_release(struct inode *inode, struct file *file) | |
3739 | { | |
3740 | if (file->f_mode & FMODE_READ) | |
3741 | seq_release(inode, file); | |
3742 | return 0; | |
3743 | } | |
3744 | ||
ea4e2bc4 | 3745 | static int |
f9349a8f | 3746 | ftrace_set_func(unsigned long *array, int *idx, char *buffer) |
ea4e2bc4 | 3747 | { |
ea4e2bc4 SR |
3748 | struct dyn_ftrace *rec; |
3749 | struct ftrace_page *pg; | |
f9349a8f | 3750 | int search_len; |
c7c6b1fe | 3751 | int fail = 1; |
f9349a8f FW |
3752 | int type, not; |
3753 | char *search; | |
3754 | bool exists; | |
3755 | int i; | |
ea4e2bc4 | 3756 | |
f9349a8f | 3757 | /* decode regex */ |
3f6fe06d | 3758 | type = filter_parse_regex(buffer, strlen(buffer), &search, ¬); |
c7c6b1fe LZ |
3759 | if (!not && *idx >= FTRACE_GRAPH_MAX_FUNCS) |
3760 | return -EBUSY; | |
f9349a8f FW |
3761 | |
3762 | search_len = strlen(search); | |
3763 | ||
52baf119 | 3764 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
3765 | |
3766 | if (unlikely(ftrace_disabled)) { | |
3767 | mutex_unlock(&ftrace_lock); | |
3768 | return -ENODEV; | |
3769 | } | |
3770 | ||
265c831c SR |
3771 | do_for_each_ftrace_rec(pg, rec) { |
3772 | ||
b9df92d2 | 3773 | if (ftrace_match_record(rec, NULL, search, search_len, type)) { |
c7c6b1fe | 3774 | /* if it is in the array */ |
f9349a8f | 3775 | exists = false; |
c7c6b1fe | 3776 | for (i = 0; i < *idx; i++) { |
f9349a8f FW |
3777 | if (array[i] == rec->ip) { |
3778 | exists = true; | |
265c831c SR |
3779 | break; |
3780 | } | |
c7c6b1fe LZ |
3781 | } |
3782 | ||
3783 | if (!not) { | |
3784 | fail = 0; | |
3785 | if (!exists) { | |
3786 | array[(*idx)++] = rec->ip; | |
3787 | if (*idx >= FTRACE_GRAPH_MAX_FUNCS) | |
3788 | goto out; | |
3789 | } | |
3790 | } else { | |
3791 | if (exists) { | |
3792 | array[i] = array[--(*idx)]; | |
3793 | array[*idx] = 0; | |
3794 | fail = 0; | |
3795 | } | |
3796 | } | |
ea4e2bc4 | 3797 | } |
265c831c | 3798 | } while_for_each_ftrace_rec(); |
c7c6b1fe | 3799 | out: |
52baf119 | 3800 | mutex_unlock(&ftrace_lock); |
ea4e2bc4 | 3801 | |
c7c6b1fe LZ |
3802 | if (fail) |
3803 | return -EINVAL; | |
3804 | ||
9f50afcc NK |
3805 | ftrace_graph_filter_enabled = !!(*idx); |
3806 | ||
c7c6b1fe | 3807 | return 0; |
ea4e2bc4 SR |
3808 | } |
3809 | ||
3810 | static ssize_t | |
3811 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
3812 | size_t cnt, loff_t *ppos) | |
3813 | { | |
689fd8b6 | 3814 | struct trace_parser parser; |
4ba7978e | 3815 | ssize_t read, ret; |
ea4e2bc4 | 3816 | |
c7c6b1fe | 3817 | if (!cnt) |
ea4e2bc4 SR |
3818 | return 0; |
3819 | ||
3820 | mutex_lock(&graph_lock); | |
3821 | ||
689fd8b6 | 3822 | if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) { |
3823 | ret = -ENOMEM; | |
1eb90f13 | 3824 | goto out_unlock; |
ea4e2bc4 SR |
3825 | } |
3826 | ||
689fd8b6 | 3827 | read = trace_get_user(&parser, ubuf, cnt, ppos); |
ea4e2bc4 | 3828 | |
4ba7978e | 3829 | if (read >= 0 && trace_parser_loaded((&parser))) { |
689fd8b6 | 3830 | parser.buffer[parser.idx] = 0; |
3831 | ||
3832 | /* we allow only one expression at a time */ | |
a4ec5e0c | 3833 | ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, |
689fd8b6 | 3834 | parser.buffer); |
ea4e2bc4 | 3835 | if (ret) |
1eb90f13 | 3836 | goto out_free; |
ea4e2bc4 | 3837 | } |
ea4e2bc4 SR |
3838 | |
3839 | ret = read; | |
1eb90f13 LZ |
3840 | |
3841 | out_free: | |
689fd8b6 | 3842 | trace_parser_put(&parser); |
1eb90f13 | 3843 | out_unlock: |
ea4e2bc4 SR |
3844 | mutex_unlock(&graph_lock); |
3845 | ||
3846 | return ret; | |
3847 | } | |
3848 | ||
3849 | static const struct file_operations ftrace_graph_fops = { | |
87827111 LZ |
3850 | .open = ftrace_graph_open, |
3851 | .read = seq_read, | |
3852 | .write = ftrace_graph_write, | |
6a76f8c0 | 3853 | .llseek = ftrace_filter_lseek, |
87827111 | 3854 | .release = ftrace_graph_release, |
ea4e2bc4 SR |
3855 | }; |
3856 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
3857 | ||
df4fc315 | 3858 | static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) |
5072c59f | 3859 | { |
5072c59f | 3860 | |
5452af66 FW |
3861 | trace_create_file("available_filter_functions", 0444, |
3862 | d_tracer, NULL, &ftrace_avail_fops); | |
5072c59f | 3863 | |
647bcd03 SR |
3864 | trace_create_file("enabled_functions", 0444, |
3865 | d_tracer, NULL, &ftrace_enabled_fops); | |
3866 | ||
5452af66 FW |
3867 | trace_create_file("set_ftrace_filter", 0644, d_tracer, |
3868 | NULL, &ftrace_filter_fops); | |
41c52c0d | 3869 | |
5452af66 | 3870 | trace_create_file("set_ftrace_notrace", 0644, d_tracer, |
41c52c0d | 3871 | NULL, &ftrace_notrace_fops); |
ad90c0e3 | 3872 | |
ea4e2bc4 | 3873 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5452af66 | 3874 | trace_create_file("set_graph_function", 0444, d_tracer, |
ea4e2bc4 SR |
3875 | NULL, |
3876 | &ftrace_graph_fops); | |
ea4e2bc4 SR |
3877 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
3878 | ||
5072c59f SR |
3879 | return 0; |
3880 | } | |
3881 | ||
9fd49328 | 3882 | static int ftrace_cmp_ips(const void *a, const void *b) |
68950619 | 3883 | { |
9fd49328 SR |
3884 | const unsigned long *ipa = a; |
3885 | const unsigned long *ipb = b; | |
68950619 | 3886 | |
9fd49328 SR |
3887 | if (*ipa > *ipb) |
3888 | return 1; | |
3889 | if (*ipa < *ipb) | |
3890 | return -1; | |
3891 | return 0; | |
3892 | } | |
3893 | ||
3894 | static void ftrace_swap_ips(void *a, void *b, int size) | |
3895 | { | |
3896 | unsigned long *ipa = a; | |
3897 | unsigned long *ipb = b; | |
3898 | unsigned long t; | |
3899 | ||
3900 | t = *ipa; | |
3901 | *ipa = *ipb; | |
3902 | *ipb = t; | |
68950619 SR |
3903 | } |
3904 | ||
5cb084bb | 3905 | static int ftrace_process_locs(struct module *mod, |
31e88909 | 3906 | unsigned long *start, |
68bf21aa SR |
3907 | unsigned long *end) |
3908 | { | |
706c81f8 | 3909 | struct ftrace_page *start_pg; |
a7900875 | 3910 | struct ftrace_page *pg; |
706c81f8 | 3911 | struct dyn_ftrace *rec; |
a7900875 | 3912 | unsigned long count; |
68bf21aa SR |
3913 | unsigned long *p; |
3914 | unsigned long addr; | |
4376cac6 | 3915 | unsigned long flags = 0; /* Shut up gcc */ |
a7900875 SR |
3916 | int ret = -ENOMEM; |
3917 | ||
3918 | count = end - start; | |
3919 | ||
3920 | if (!count) | |
3921 | return 0; | |
3922 | ||
9fd49328 SR |
3923 | sort(start, count, sizeof(*start), |
3924 | ftrace_cmp_ips, ftrace_swap_ips); | |
3925 | ||
706c81f8 SR |
3926 | start_pg = ftrace_allocate_pages(count); |
3927 | if (!start_pg) | |
a7900875 | 3928 | return -ENOMEM; |
68bf21aa | 3929 | |
e6ea44e9 | 3930 | mutex_lock(&ftrace_lock); |
a7900875 | 3931 | |
32082309 SR |
3932 | /* |
3933 | * Core and each module needs their own pages, as | |
3934 | * modules will free them when they are removed. | |
3935 | * Force a new page to be allocated for modules. | |
3936 | */ | |
a7900875 SR |
3937 | if (!mod) { |
3938 | WARN_ON(ftrace_pages || ftrace_pages_start); | |
3939 | /* First initialization */ | |
706c81f8 | 3940 | ftrace_pages = ftrace_pages_start = start_pg; |
a7900875 | 3941 | } else { |
32082309 | 3942 | if (!ftrace_pages) |
a7900875 | 3943 | goto out; |
32082309 | 3944 | |
a7900875 SR |
3945 | if (WARN_ON(ftrace_pages->next)) { |
3946 | /* Hmm, we have free pages? */ | |
3947 | while (ftrace_pages->next) | |
3948 | ftrace_pages = ftrace_pages->next; | |
32082309 | 3949 | } |
a7900875 | 3950 | |
706c81f8 | 3951 | ftrace_pages->next = start_pg; |
32082309 SR |
3952 | } |
3953 | ||
68bf21aa | 3954 | p = start; |
706c81f8 | 3955 | pg = start_pg; |
68bf21aa SR |
3956 | while (p < end) { |
3957 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
3958 | /* |
3959 | * Some architecture linkers will pad between | |
3960 | * the different mcount_loc sections of different | |
3961 | * object files to satisfy alignments. | |
3962 | * Skip any NULL pointers. | |
3963 | */ | |
3964 | if (!addr) | |
3965 | continue; | |
706c81f8 SR |
3966 | |
3967 | if (pg->index == pg->size) { | |
3968 | /* We should have allocated enough */ | |
3969 | if (WARN_ON(!pg->next)) | |
3970 | break; | |
3971 | pg = pg->next; | |
3972 | } | |
3973 | ||
3974 | rec = &pg->records[pg->index++]; | |
3975 | rec->ip = addr; | |
68bf21aa SR |
3976 | } |
3977 | ||
706c81f8 SR |
3978 | /* We should have used all pages */ |
3979 | WARN_ON(pg->next); | |
3980 | ||
3981 | /* Assign the last page to ftrace_pages */ | |
3982 | ftrace_pages = pg; | |
3983 | ||
85ae32ae | 3984 | /* These new locations need to be initialized */ |
706c81f8 | 3985 | ftrace_new_pgs = start_pg; |
85ae32ae | 3986 | |
a4f18ed1 | 3987 | /* |
4376cac6 SR |
3988 | * We only need to disable interrupts on start up |
3989 | * because we are modifying code that an interrupt | |
3990 | * may execute, and the modification is not atomic. | |
3991 | * But for modules, nothing runs the code we modify | |
3992 | * until we are finished with it, and there's no | |
3993 | * reason to cause large interrupt latencies while we do it. | |
a4f18ed1 | 3994 | */ |
4376cac6 SR |
3995 | if (!mod) |
3996 | local_irq_save(flags); | |
31e88909 | 3997 | ftrace_update_code(mod); |
4376cac6 SR |
3998 | if (!mod) |
3999 | local_irq_restore(flags); | |
a7900875 SR |
4000 | ret = 0; |
4001 | out: | |
e6ea44e9 | 4002 | mutex_unlock(&ftrace_lock); |
68bf21aa | 4003 | |
a7900875 | 4004 | return ret; |
68bf21aa SR |
4005 | } |
4006 | ||
93eb677d | 4007 | #ifdef CONFIG_MODULES |
32082309 SR |
4008 | |
4009 | #define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next) | |
4010 | ||
e7247a15 | 4011 | void ftrace_release_mod(struct module *mod) |
93eb677d SR |
4012 | { |
4013 | struct dyn_ftrace *rec; | |
32082309 | 4014 | struct ftrace_page **last_pg; |
93eb677d | 4015 | struct ftrace_page *pg; |
a7900875 | 4016 | int order; |
93eb677d | 4017 | |
45a4a237 SR |
4018 | mutex_lock(&ftrace_lock); |
4019 | ||
e7247a15 | 4020 | if (ftrace_disabled) |
45a4a237 | 4021 | goto out_unlock; |
93eb677d | 4022 | |
32082309 SR |
4023 | /* |
4024 | * Each module has its own ftrace_pages, remove | |
4025 | * them from the list. | |
4026 | */ | |
4027 | last_pg = &ftrace_pages_start; | |
4028 | for (pg = ftrace_pages_start; pg; pg = *last_pg) { | |
4029 | rec = &pg->records[0]; | |
e7247a15 | 4030 | if (within_module_core(rec->ip, mod)) { |
93eb677d | 4031 | /* |
32082309 SR |
4032 | * As core pages are first, the first |
4033 | * page should never be a module page. | |
93eb677d | 4034 | */ |
32082309 SR |
4035 | if (WARN_ON(pg == ftrace_pages_start)) |
4036 | goto out_unlock; | |
4037 | ||
4038 | /* Check if we are deleting the last page */ | |
4039 | if (pg == ftrace_pages) | |
4040 | ftrace_pages = next_to_ftrace_page(last_pg); | |
4041 | ||
4042 | *last_pg = pg->next; | |
a7900875 SR |
4043 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); |
4044 | free_pages((unsigned long)pg->records, order); | |
4045 | kfree(pg); | |
32082309 SR |
4046 | } else |
4047 | last_pg = &pg->next; | |
4048 | } | |
45a4a237 | 4049 | out_unlock: |
93eb677d SR |
4050 | mutex_unlock(&ftrace_lock); |
4051 | } | |
4052 | ||
4053 | static void ftrace_init_module(struct module *mod, | |
4054 | unsigned long *start, unsigned long *end) | |
90d595fe | 4055 | { |
00fd61ae | 4056 | if (ftrace_disabled || start == end) |
fed1939c | 4057 | return; |
5cb084bb | 4058 | ftrace_process_locs(mod, start, end); |
90d595fe SR |
4059 | } |
4060 | ||
8c189ea6 SRRH |
4061 | static int ftrace_module_notify_enter(struct notifier_block *self, |
4062 | unsigned long val, void *data) | |
93eb677d SR |
4063 | { |
4064 | struct module *mod = data; | |
4065 | ||
8c189ea6 | 4066 | if (val == MODULE_STATE_COMING) |
93eb677d SR |
4067 | ftrace_init_module(mod, mod->ftrace_callsites, |
4068 | mod->ftrace_callsites + | |
4069 | mod->num_ftrace_callsites); | |
8c189ea6 SRRH |
4070 | return 0; |
4071 | } | |
4072 | ||
4073 | static int ftrace_module_notify_exit(struct notifier_block *self, | |
4074 | unsigned long val, void *data) | |
4075 | { | |
4076 | struct module *mod = data; | |
4077 | ||
4078 | if (val == MODULE_STATE_GOING) | |
e7247a15 | 4079 | ftrace_release_mod(mod); |
93eb677d SR |
4080 | |
4081 | return 0; | |
4082 | } | |
4083 | #else | |
8c189ea6 SRRH |
4084 | static int ftrace_module_notify_enter(struct notifier_block *self, |
4085 | unsigned long val, void *data) | |
4086 | { | |
4087 | return 0; | |
4088 | } | |
4089 | static int ftrace_module_notify_exit(struct notifier_block *self, | |
4090 | unsigned long val, void *data) | |
93eb677d SR |
4091 | { |
4092 | return 0; | |
4093 | } | |
4094 | #endif /* CONFIG_MODULES */ | |
4095 | ||
8c189ea6 SRRH |
4096 | struct notifier_block ftrace_module_enter_nb = { |
4097 | .notifier_call = ftrace_module_notify_enter, | |
c1bf08ac | 4098 | .priority = INT_MAX, /* Run before anything that can use kprobes */ |
93eb677d SR |
4099 | }; |
4100 | ||
8c189ea6 SRRH |
4101 | struct notifier_block ftrace_module_exit_nb = { |
4102 | .notifier_call = ftrace_module_notify_exit, | |
4103 | .priority = INT_MIN, /* Run after anything that can remove kprobes */ | |
4104 | }; | |
4105 | ||
68bf21aa SR |
4106 | extern unsigned long __start_mcount_loc[]; |
4107 | extern unsigned long __stop_mcount_loc[]; | |
4108 | ||
4109 | void __init ftrace_init(void) | |
4110 | { | |
4111 | unsigned long count, addr, flags; | |
4112 | int ret; | |
4113 | ||
4114 | /* Keep the ftrace pointer to the stub */ | |
4115 | addr = (unsigned long)ftrace_stub; | |
4116 | ||
4117 | local_irq_save(flags); | |
4118 | ftrace_dyn_arch_init(&addr); | |
4119 | local_irq_restore(flags); | |
4120 | ||
4121 | /* ftrace_dyn_arch_init places the return code in addr */ | |
4122 | if (addr) | |
4123 | goto failed; | |
4124 | ||
4125 | count = __stop_mcount_loc - __start_mcount_loc; | |
4126 | ||
4127 | ret = ftrace_dyn_table_alloc(count); | |
4128 | if (ret) | |
4129 | goto failed; | |
4130 | ||
4131 | last_ftrace_enabled = ftrace_enabled = 1; | |
4132 | ||
5cb084bb | 4133 | ret = ftrace_process_locs(NULL, |
31e88909 | 4134 | __start_mcount_loc, |
68bf21aa SR |
4135 | __stop_mcount_loc); |
4136 | ||
8c189ea6 SRRH |
4137 | ret = register_module_notifier(&ftrace_module_enter_nb); |
4138 | if (ret) | |
4139 | pr_warning("Failed to register trace ftrace module enter notifier\n"); | |
4140 | ||
4141 | ret = register_module_notifier(&ftrace_module_exit_nb); | |
24ed0c4b | 4142 | if (ret) |
8c189ea6 | 4143 | pr_warning("Failed to register trace ftrace module exit notifier\n"); |
93eb677d | 4144 | |
2af15d6a SR |
4145 | set_ftrace_early_filters(); |
4146 | ||
68bf21aa SR |
4147 | return; |
4148 | failed: | |
4149 | ftrace_disabled = 1; | |
4150 | } | |
68bf21aa | 4151 | |
3d083395 | 4152 | #else |
0b6e4d56 | 4153 | |
2b499381 | 4154 | static struct ftrace_ops global_ops = { |
bd69c30b | 4155 | .func = ftrace_stub, |
f04f24fb MH |
4156 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, |
4157 | INIT_REGEX_LOCK(global_ops) | |
bd69c30b SR |
4158 | }; |
4159 | ||
0b6e4d56 FW |
4160 | static int __init ftrace_nodyn_init(void) |
4161 | { | |
4162 | ftrace_enabled = 1; | |
4163 | return 0; | |
4164 | } | |
6f415672 | 4165 | core_initcall(ftrace_nodyn_init); |
0b6e4d56 | 4166 | |
df4fc315 SR |
4167 | static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } |
4168 | static inline void ftrace_startup_enable(int command) { } | |
5a45cfe1 | 4169 | /* Keep as macros so we do not need to define the commands */ |
3b6cfdb1 SR |
4170 | # define ftrace_startup(ops, command) \ |
4171 | ({ \ | |
4172 | (ops)->flags |= FTRACE_OPS_FL_ENABLED; \ | |
4173 | 0; \ | |
4174 | }) | |
bd69c30b | 4175 | # define ftrace_shutdown(ops, command) do { } while (0) |
c7aafc54 IM |
4176 | # define ftrace_startup_sysctl() do { } while (0) |
4177 | # define ftrace_shutdown_sysctl() do { } while (0) | |
b848914c SR |
4178 | |
4179 | static inline int | |
4180 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip) | |
4181 | { | |
4182 | return 1; | |
4183 | } | |
4184 | ||
3d083395 SR |
4185 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
4186 | ||
e248491a | 4187 | static void |
2f5f6ad9 | 4188 | ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 4189 | struct ftrace_ops *op, struct pt_regs *regs) |
e248491a | 4190 | { |
e248491a JO |
4191 | if (unlikely(trace_recursion_test(TRACE_CONTROL_BIT))) |
4192 | return; | |
4193 | ||
4194 | /* | |
4195 | * Some of the ops may be dynamically allocated, | |
4196 | * they must be freed after a synchronize_sched(). | |
4197 | */ | |
4198 | preempt_disable_notrace(); | |
4199 | trace_recursion_set(TRACE_CONTROL_BIT); | |
0a016409 | 4200 | do_for_each_ftrace_op(op, ftrace_control_list) { |
395b97a3 SRRH |
4201 | if (!(op->flags & FTRACE_OPS_FL_STUB) && |
4202 | !ftrace_function_local_disabled(op) && | |
e248491a | 4203 | ftrace_ops_test(op, ip)) |
a1e2e31d | 4204 | op->func(ip, parent_ip, op, regs); |
0a016409 | 4205 | } while_for_each_ftrace_op(op); |
e248491a JO |
4206 | trace_recursion_clear(TRACE_CONTROL_BIT); |
4207 | preempt_enable_notrace(); | |
4208 | } | |
4209 | ||
4210 | static struct ftrace_ops control_ops = { | |
f04f24fb MH |
4211 | .func = ftrace_ops_control_func, |
4212 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, | |
4213 | INIT_REGEX_LOCK(control_ops) | |
e248491a JO |
4214 | }; |
4215 | ||
2f5f6ad9 SR |
4216 | static inline void |
4217 | __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 4218 | struct ftrace_ops *ignored, struct pt_regs *regs) |
b848914c | 4219 | { |
cdbe61bf | 4220 | struct ftrace_ops *op; |
edc15caf | 4221 | int bit; |
b848914c | 4222 | |
ccf3672d SR |
4223 | if (function_trace_stop) |
4224 | return; | |
4225 | ||
edc15caf SR |
4226 | bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); |
4227 | if (bit < 0) | |
4228 | return; | |
b1cff0ad | 4229 | |
cdbe61bf SR |
4230 | /* |
4231 | * Some of the ops may be dynamically allocated, | |
4232 | * they must be freed after a synchronize_sched(). | |
4233 | */ | |
4234 | preempt_disable_notrace(); | |
0a016409 | 4235 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
b848914c | 4236 | if (ftrace_ops_test(op, ip)) |
a1e2e31d | 4237 | op->func(ip, parent_ip, op, regs); |
0a016409 | 4238 | } while_for_each_ftrace_op(op); |
cdbe61bf | 4239 | preempt_enable_notrace(); |
edc15caf | 4240 | trace_clear_recursion(bit); |
b848914c SR |
4241 | } |
4242 | ||
2f5f6ad9 SR |
4243 | /* |
4244 | * Some archs only support passing ip and parent_ip. Even though | |
4245 | * the list function ignores the op parameter, we do not want any | |
4246 | * C side effects, where a function is called without the caller | |
4247 | * sending a third parameter. | |
a1e2e31d SR |
4248 | * Archs are to support both the regs and ftrace_ops at the same time. |
4249 | * If they support ftrace_ops, it is assumed they support regs. | |
4250 | * If call backs want to use regs, they must either check for regs | |
06aeaaea MH |
4251 | * being NULL, or CONFIG_DYNAMIC_FTRACE_WITH_REGS. |
4252 | * Note, CONFIG_DYNAMIC_FTRACE_WITH_REGS expects a full regs to be saved. | |
a1e2e31d SR |
4253 | * An architecture can pass partial regs with ftrace_ops and still |
4254 | * set the ARCH_SUPPORT_FTARCE_OPS. | |
2f5f6ad9 SR |
4255 | */ |
4256 | #if ARCH_SUPPORTS_FTRACE_OPS | |
4257 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 4258 | struct ftrace_ops *op, struct pt_regs *regs) |
2f5f6ad9 | 4259 | { |
a1e2e31d | 4260 | __ftrace_ops_list_func(ip, parent_ip, NULL, regs); |
2f5f6ad9 SR |
4261 | } |
4262 | #else | |
4263 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip) | |
4264 | { | |
a1e2e31d | 4265 | __ftrace_ops_list_func(ip, parent_ip, NULL, NULL); |
2f5f6ad9 SR |
4266 | } |
4267 | #endif | |
4268 | ||
e32d8956 | 4269 | static void clear_ftrace_swapper(void) |
978f3a45 SR |
4270 | { |
4271 | struct task_struct *p; | |
e32d8956 | 4272 | int cpu; |
978f3a45 | 4273 | |
e32d8956 SR |
4274 | get_online_cpus(); |
4275 | for_each_online_cpu(cpu) { | |
4276 | p = idle_task(cpu); | |
978f3a45 | 4277 | clear_tsk_trace_trace(p); |
e32d8956 SR |
4278 | } |
4279 | put_online_cpus(); | |
4280 | } | |
978f3a45 | 4281 | |
e32d8956 SR |
4282 | static void set_ftrace_swapper(void) |
4283 | { | |
4284 | struct task_struct *p; | |
4285 | int cpu; | |
4286 | ||
4287 | get_online_cpus(); | |
4288 | for_each_online_cpu(cpu) { | |
4289 | p = idle_task(cpu); | |
4290 | set_tsk_trace_trace(p); | |
4291 | } | |
4292 | put_online_cpus(); | |
978f3a45 SR |
4293 | } |
4294 | ||
e32d8956 SR |
4295 | static void clear_ftrace_pid(struct pid *pid) |
4296 | { | |
4297 | struct task_struct *p; | |
4298 | ||
229c4ef8 | 4299 | rcu_read_lock(); |
e32d8956 SR |
4300 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
4301 | clear_tsk_trace_trace(p); | |
4302 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 ON |
4303 | rcu_read_unlock(); |
4304 | ||
e32d8956 SR |
4305 | put_pid(pid); |
4306 | } | |
4307 | ||
4308 | static void set_ftrace_pid(struct pid *pid) | |
978f3a45 SR |
4309 | { |
4310 | struct task_struct *p; | |
4311 | ||
229c4ef8 | 4312 | rcu_read_lock(); |
978f3a45 SR |
4313 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
4314 | set_tsk_trace_trace(p); | |
4315 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 | 4316 | rcu_read_unlock(); |
978f3a45 SR |
4317 | } |
4318 | ||
756d17ee | 4319 | static void clear_ftrace_pid_task(struct pid *pid) |
e32d8956 | 4320 | { |
756d17ee | 4321 | if (pid == ftrace_swapper_pid) |
e32d8956 SR |
4322 | clear_ftrace_swapper(); |
4323 | else | |
756d17ee | 4324 | clear_ftrace_pid(pid); |
e32d8956 SR |
4325 | } |
4326 | ||
4327 | static void set_ftrace_pid_task(struct pid *pid) | |
4328 | { | |
4329 | if (pid == ftrace_swapper_pid) | |
4330 | set_ftrace_swapper(); | |
4331 | else | |
4332 | set_ftrace_pid(pid); | |
4333 | } | |
4334 | ||
756d17ee | 4335 | static int ftrace_pid_add(int p) |
df4fc315 | 4336 | { |
978f3a45 | 4337 | struct pid *pid; |
756d17ee | 4338 | struct ftrace_pid *fpid; |
4339 | int ret = -EINVAL; | |
df4fc315 | 4340 | |
756d17ee | 4341 | mutex_lock(&ftrace_lock); |
df4fc315 | 4342 | |
756d17ee | 4343 | if (!p) |
4344 | pid = ftrace_swapper_pid; | |
4345 | else | |
4346 | pid = find_get_pid(p); | |
df4fc315 | 4347 | |
756d17ee | 4348 | if (!pid) |
4349 | goto out; | |
df4fc315 | 4350 | |
756d17ee | 4351 | ret = 0; |
df4fc315 | 4352 | |
756d17ee | 4353 | list_for_each_entry(fpid, &ftrace_pids, list) |
4354 | if (fpid->pid == pid) | |
4355 | goto out_put; | |
978f3a45 | 4356 | |
756d17ee | 4357 | ret = -ENOMEM; |
df4fc315 | 4358 | |
756d17ee | 4359 | fpid = kmalloc(sizeof(*fpid), GFP_KERNEL); |
4360 | if (!fpid) | |
4361 | goto out_put; | |
df4fc315 | 4362 | |
756d17ee | 4363 | list_add(&fpid->list, &ftrace_pids); |
4364 | fpid->pid = pid; | |
0ef8cde5 | 4365 | |
756d17ee | 4366 | set_ftrace_pid_task(pid); |
978f3a45 | 4367 | |
756d17ee | 4368 | ftrace_update_pid_func(); |
4369 | ftrace_startup_enable(0); | |
4370 | ||
4371 | mutex_unlock(&ftrace_lock); | |
4372 | return 0; | |
4373 | ||
4374 | out_put: | |
4375 | if (pid != ftrace_swapper_pid) | |
4376 | put_pid(pid); | |
978f3a45 | 4377 | |
756d17ee | 4378 | out: |
4379 | mutex_unlock(&ftrace_lock); | |
4380 | return ret; | |
4381 | } | |
4382 | ||
4383 | static void ftrace_pid_reset(void) | |
4384 | { | |
4385 | struct ftrace_pid *fpid, *safe; | |
978f3a45 | 4386 | |
756d17ee | 4387 | mutex_lock(&ftrace_lock); |
4388 | list_for_each_entry_safe(fpid, safe, &ftrace_pids, list) { | |
4389 | struct pid *pid = fpid->pid; | |
4390 | ||
4391 | clear_ftrace_pid_task(pid); | |
4392 | ||
4393 | list_del(&fpid->list); | |
4394 | kfree(fpid); | |
df4fc315 SR |
4395 | } |
4396 | ||
df4fc315 SR |
4397 | ftrace_update_pid_func(); |
4398 | ftrace_startup_enable(0); | |
4399 | ||
e6ea44e9 | 4400 | mutex_unlock(&ftrace_lock); |
756d17ee | 4401 | } |
df4fc315 | 4402 | |
756d17ee | 4403 | static void *fpid_start(struct seq_file *m, loff_t *pos) |
4404 | { | |
4405 | mutex_lock(&ftrace_lock); | |
4406 | ||
4407 | if (list_empty(&ftrace_pids) && (!*pos)) | |
4408 | return (void *) 1; | |
4409 | ||
4410 | return seq_list_start(&ftrace_pids, *pos); | |
4411 | } | |
4412 | ||
4413 | static void *fpid_next(struct seq_file *m, void *v, loff_t *pos) | |
4414 | { | |
4415 | if (v == (void *)1) | |
4416 | return NULL; | |
4417 | ||
4418 | return seq_list_next(v, &ftrace_pids, pos); | |
4419 | } | |
4420 | ||
4421 | static void fpid_stop(struct seq_file *m, void *p) | |
4422 | { | |
4423 | mutex_unlock(&ftrace_lock); | |
4424 | } | |
4425 | ||
4426 | static int fpid_show(struct seq_file *m, void *v) | |
4427 | { | |
4428 | const struct ftrace_pid *fpid = list_entry(v, struct ftrace_pid, list); | |
4429 | ||
4430 | if (v == (void *)1) { | |
4431 | seq_printf(m, "no pid\n"); | |
4432 | return 0; | |
4433 | } | |
4434 | ||
4435 | if (fpid->pid == ftrace_swapper_pid) | |
4436 | seq_printf(m, "swapper tasks\n"); | |
4437 | else | |
4438 | seq_printf(m, "%u\n", pid_vnr(fpid->pid)); | |
4439 | ||
4440 | return 0; | |
4441 | } | |
4442 | ||
4443 | static const struct seq_operations ftrace_pid_sops = { | |
4444 | .start = fpid_start, | |
4445 | .next = fpid_next, | |
4446 | .stop = fpid_stop, | |
4447 | .show = fpid_show, | |
4448 | }; | |
4449 | ||
4450 | static int | |
4451 | ftrace_pid_open(struct inode *inode, struct file *file) | |
4452 | { | |
4453 | int ret = 0; | |
4454 | ||
4455 | if ((file->f_mode & FMODE_WRITE) && | |
4456 | (file->f_flags & O_TRUNC)) | |
4457 | ftrace_pid_reset(); | |
4458 | ||
4459 | if (file->f_mode & FMODE_READ) | |
4460 | ret = seq_open(file, &ftrace_pid_sops); | |
4461 | ||
4462 | return ret; | |
4463 | } | |
4464 | ||
df4fc315 SR |
4465 | static ssize_t |
4466 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
4467 | size_t cnt, loff_t *ppos) | |
4468 | { | |
457dc928 | 4469 | char buf[64], *tmp; |
df4fc315 SR |
4470 | long val; |
4471 | int ret; | |
4472 | ||
4473 | if (cnt >= sizeof(buf)) | |
4474 | return -EINVAL; | |
4475 | ||
4476 | if (copy_from_user(&buf, ubuf, cnt)) | |
4477 | return -EFAULT; | |
4478 | ||
4479 | buf[cnt] = 0; | |
4480 | ||
756d17ee | 4481 | /* |
4482 | * Allow "echo > set_ftrace_pid" or "echo -n '' > set_ftrace_pid" | |
4483 | * to clean the filter quietly. | |
4484 | */ | |
457dc928 IM |
4485 | tmp = strstrip(buf); |
4486 | if (strlen(tmp) == 0) | |
756d17ee | 4487 | return 1; |
4488 | ||
bcd83ea6 | 4489 | ret = kstrtol(tmp, 10, &val); |
df4fc315 SR |
4490 | if (ret < 0) |
4491 | return ret; | |
4492 | ||
756d17ee | 4493 | ret = ftrace_pid_add(val); |
df4fc315 | 4494 | |
756d17ee | 4495 | return ret ? ret : cnt; |
4496 | } | |
df4fc315 | 4497 | |
756d17ee | 4498 | static int |
4499 | ftrace_pid_release(struct inode *inode, struct file *file) | |
4500 | { | |
4501 | if (file->f_mode & FMODE_READ) | |
4502 | seq_release(inode, file); | |
df4fc315 | 4503 | |
756d17ee | 4504 | return 0; |
df4fc315 SR |
4505 | } |
4506 | ||
5e2336a0 | 4507 | static const struct file_operations ftrace_pid_fops = { |
756d17ee | 4508 | .open = ftrace_pid_open, |
4509 | .write = ftrace_pid_write, | |
4510 | .read = seq_read, | |
6a76f8c0 | 4511 | .llseek = ftrace_filter_lseek, |
756d17ee | 4512 | .release = ftrace_pid_release, |
df4fc315 SR |
4513 | }; |
4514 | ||
4515 | static __init int ftrace_init_debugfs(void) | |
4516 | { | |
4517 | struct dentry *d_tracer; | |
df4fc315 SR |
4518 | |
4519 | d_tracer = tracing_init_dentry(); | |
4520 | if (!d_tracer) | |
4521 | return 0; | |
4522 | ||
4523 | ftrace_init_dyn_debugfs(d_tracer); | |
4524 | ||
5452af66 FW |
4525 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
4526 | NULL, &ftrace_pid_fops); | |
493762fc SR |
4527 | |
4528 | ftrace_profile_debugfs(d_tracer); | |
4529 | ||
df4fc315 SR |
4530 | return 0; |
4531 | } | |
df4fc315 SR |
4532 | fs_initcall(ftrace_init_debugfs); |
4533 | ||
a2bb6a3d | 4534 | /** |
81adbdc0 | 4535 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
4536 | * |
4537 | * This function should be used by panic code. It stops ftrace | |
4538 | * but in a not so nice way. If you need to simply kill ftrace | |
4539 | * from a non-atomic section, use ftrace_kill. | |
4540 | */ | |
81adbdc0 | 4541 | void ftrace_kill(void) |
a2bb6a3d SR |
4542 | { |
4543 | ftrace_disabled = 1; | |
4544 | ftrace_enabled = 0; | |
a2bb6a3d SR |
4545 | clear_ftrace_function(); |
4546 | } | |
4547 | ||
e0a413f6 SR |
4548 | /** |
4549 | * Test if ftrace is dead or not. | |
4550 | */ | |
4551 | int ftrace_is_dead(void) | |
4552 | { | |
4553 | return ftrace_disabled; | |
4554 | } | |
4555 | ||
16444a8a | 4556 | /** |
3d083395 SR |
4557 | * register_ftrace_function - register a function for profiling |
4558 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 4559 | * |
3d083395 SR |
4560 | * Register a function to be called by all functions in the |
4561 | * kernel. | |
4562 | * | |
4563 | * Note: @ops->func and all the functions it calls must be labeled | |
4564 | * with "notrace", otherwise it will go into a | |
4565 | * recursive loop. | |
16444a8a | 4566 | */ |
3d083395 | 4567 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 4568 | { |
45a4a237 | 4569 | int ret = -1; |
4eebcc81 | 4570 | |
f04f24fb MH |
4571 | ftrace_ops_init(ops); |
4572 | ||
e6ea44e9 | 4573 | mutex_lock(&ftrace_lock); |
e7d3737e | 4574 | |
b0fc494f | 4575 | ret = __register_ftrace_function(ops); |
b848914c | 4576 | if (!ret) |
a1cd6173 | 4577 | ret = ftrace_startup(ops, 0); |
b848914c | 4578 | |
e6ea44e9 | 4579 | mutex_unlock(&ftrace_lock); |
8d240dd8 | 4580 | |
b0fc494f | 4581 | return ret; |
3d083395 | 4582 | } |
cdbe61bf | 4583 | EXPORT_SYMBOL_GPL(register_ftrace_function); |
3d083395 SR |
4584 | |
4585 | /** | |
32632920 | 4586 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
4587 | * @ops - ops structure that holds the function to unregister |
4588 | * | |
4589 | * Unregister a function that was added to be called by ftrace profiling. | |
4590 | */ | |
4591 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
4592 | { | |
4593 | int ret; | |
4594 | ||
e6ea44e9 | 4595 | mutex_lock(&ftrace_lock); |
3d083395 | 4596 | ret = __unregister_ftrace_function(ops); |
b848914c SR |
4597 | if (!ret) |
4598 | ftrace_shutdown(ops, 0); | |
e6ea44e9 | 4599 | mutex_unlock(&ftrace_lock); |
b0fc494f SR |
4600 | |
4601 | return ret; | |
4602 | } | |
cdbe61bf | 4603 | EXPORT_SYMBOL_GPL(unregister_ftrace_function); |
b0fc494f | 4604 | |
e309b41d | 4605 | int |
b0fc494f | 4606 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
8d65af78 | 4607 | void __user *buffer, size_t *lenp, |
b0fc494f SR |
4608 | loff_t *ppos) |
4609 | { | |
45a4a237 | 4610 | int ret = -ENODEV; |
4eebcc81 | 4611 | |
e6ea44e9 | 4612 | mutex_lock(&ftrace_lock); |
b0fc494f | 4613 | |
45a4a237 SR |
4614 | if (unlikely(ftrace_disabled)) |
4615 | goto out; | |
4616 | ||
4617 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
b0fc494f | 4618 | |
a32c7765 | 4619 | if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) |
b0fc494f SR |
4620 | goto out; |
4621 | ||
a32c7765 | 4622 | last_ftrace_enabled = !!ftrace_enabled; |
b0fc494f SR |
4623 | |
4624 | if (ftrace_enabled) { | |
4625 | ||
4626 | ftrace_startup_sysctl(); | |
4627 | ||
4628 | /* we are starting ftrace again */ | |
5000c418 JK |
4629 | if (ftrace_ops_list != &ftrace_list_end) |
4630 | update_ftrace_function(); | |
b0fc494f SR |
4631 | |
4632 | } else { | |
4633 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
4634 | ftrace_trace_function = ftrace_stub; | |
4635 | ||
4636 | ftrace_shutdown_sysctl(); | |
4637 | } | |
4638 | ||
4639 | out: | |
e6ea44e9 | 4640 | mutex_unlock(&ftrace_lock); |
3d083395 | 4641 | return ret; |
16444a8a | 4642 | } |
f17845e5 | 4643 | |
fb52607a | 4644 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 4645 | |
597af815 | 4646 | static int ftrace_graph_active; |
4a2b8dda | 4647 | static struct notifier_block ftrace_suspend_notifier; |
e7d3737e | 4648 | |
e49dc19c SR |
4649 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
4650 | { | |
4651 | return 0; | |
4652 | } | |
4653 | ||
287b6e68 FW |
4654 | /* The callbacks that hook a function */ |
4655 | trace_func_graph_ret_t ftrace_graph_return = | |
4656 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 4657 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
4658 | |
4659 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
4660 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
4661 | { | |
4662 | int i; | |
4663 | int ret = 0; | |
4664 | unsigned long flags; | |
4665 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; | |
4666 | struct task_struct *g, *t; | |
4667 | ||
4668 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
4669 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
4670 | * sizeof(struct ftrace_ret_stack), | |
4671 | GFP_KERNEL); | |
4672 | if (!ret_stack_list[i]) { | |
4673 | start = 0; | |
4674 | end = i; | |
4675 | ret = -ENOMEM; | |
4676 | goto free; | |
4677 | } | |
4678 | } | |
4679 | ||
4680 | read_lock_irqsave(&tasklist_lock, flags); | |
4681 | do_each_thread(g, t) { | |
4682 | if (start == end) { | |
4683 | ret = -EAGAIN; | |
4684 | goto unlock; | |
4685 | } | |
4686 | ||
4687 | if (t->ret_stack == NULL) { | |
380c4b14 | 4688 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 | 4689 | atomic_set(&t->trace_overrun, 0); |
26c01624 SR |
4690 | t->curr_ret_stack = -1; |
4691 | /* Make sure the tasks see the -1 first: */ | |
4692 | smp_wmb(); | |
4693 | t->ret_stack = ret_stack_list[start++]; | |
f201ae23 FW |
4694 | } |
4695 | } while_each_thread(g, t); | |
4696 | ||
4697 | unlock: | |
4698 | read_unlock_irqrestore(&tasklist_lock, flags); | |
4699 | free: | |
4700 | for (i = start; i < end; i++) | |
4701 | kfree(ret_stack_list[i]); | |
4702 | return ret; | |
4703 | } | |
4704 | ||
8aef2d28 | 4705 | static void |
38516ab5 SR |
4706 | ftrace_graph_probe_sched_switch(void *ignore, |
4707 | struct task_struct *prev, struct task_struct *next) | |
8aef2d28 SR |
4708 | { |
4709 | unsigned long long timestamp; | |
4710 | int index; | |
4711 | ||
be6f164a SR |
4712 | /* |
4713 | * Does the user want to count the time a function was asleep. | |
4714 | * If so, do not update the time stamps. | |
4715 | */ | |
4716 | if (trace_flags & TRACE_ITER_SLEEP_TIME) | |
4717 | return; | |
4718 | ||
8aef2d28 SR |
4719 | timestamp = trace_clock_local(); |
4720 | ||
4721 | prev->ftrace_timestamp = timestamp; | |
4722 | ||
4723 | /* only process tasks that we timestamped */ | |
4724 | if (!next->ftrace_timestamp) | |
4725 | return; | |
4726 | ||
4727 | /* | |
4728 | * Update all the counters in next to make up for the | |
4729 | * time next was sleeping. | |
4730 | */ | |
4731 | timestamp -= next->ftrace_timestamp; | |
4732 | ||
4733 | for (index = next->curr_ret_stack; index >= 0; index--) | |
4734 | next->ret_stack[index].calltime += timestamp; | |
4735 | } | |
4736 | ||
f201ae23 | 4737 | /* Allocate a return stack for each task */ |
fb52607a | 4738 | static int start_graph_tracing(void) |
f201ae23 FW |
4739 | { |
4740 | struct ftrace_ret_stack **ret_stack_list; | |
5b058bcd | 4741 | int ret, cpu; |
f201ae23 FW |
4742 | |
4743 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
4744 | sizeof(struct ftrace_ret_stack *), | |
4745 | GFP_KERNEL); | |
4746 | ||
4747 | if (!ret_stack_list) | |
4748 | return -ENOMEM; | |
4749 | ||
5b058bcd | 4750 | /* The cpu_boot init_task->ret_stack will never be freed */ |
179c498a SR |
4751 | for_each_online_cpu(cpu) { |
4752 | if (!idle_task(cpu)->ret_stack) | |
868baf07 | 4753 | ftrace_graph_init_idle_task(idle_task(cpu), cpu); |
179c498a | 4754 | } |
5b058bcd | 4755 | |
f201ae23 FW |
4756 | do { |
4757 | ret = alloc_retstack_tasklist(ret_stack_list); | |
4758 | } while (ret == -EAGAIN); | |
4759 | ||
8aef2d28 | 4760 | if (!ret) { |
38516ab5 | 4761 | ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
8aef2d28 SR |
4762 | if (ret) |
4763 | pr_info("ftrace_graph: Couldn't activate tracepoint" | |
4764 | " probe to kernel_sched_switch\n"); | |
4765 | } | |
4766 | ||
f201ae23 FW |
4767 | kfree(ret_stack_list); |
4768 | return ret; | |
4769 | } | |
4770 | ||
4a2b8dda FW |
4771 | /* |
4772 | * Hibernation protection. | |
4773 | * The state of the current task is too much unstable during | |
4774 | * suspend/restore to disk. We want to protect against that. | |
4775 | */ | |
4776 | static int | |
4777 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, | |
4778 | void *unused) | |
4779 | { | |
4780 | switch (state) { | |
4781 | case PM_HIBERNATION_PREPARE: | |
4782 | pause_graph_tracing(); | |
4783 | break; | |
4784 | ||
4785 | case PM_POST_HIBERNATION: | |
4786 | unpause_graph_tracing(); | |
4787 | break; | |
4788 | } | |
4789 | return NOTIFY_DONE; | |
4790 | } | |
4791 | ||
287b6e68 FW |
4792 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
4793 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 4794 | { |
e7d3737e FW |
4795 | int ret = 0; |
4796 | ||
e6ea44e9 | 4797 | mutex_lock(&ftrace_lock); |
e7d3737e | 4798 | |
05ce5818 | 4799 | /* we currently allow only one tracer registered at a time */ |
597af815 | 4800 | if (ftrace_graph_active) { |
05ce5818 SR |
4801 | ret = -EBUSY; |
4802 | goto out; | |
4803 | } | |
4804 | ||
4a2b8dda FW |
4805 | ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call; |
4806 | register_pm_notifier(&ftrace_suspend_notifier); | |
4807 | ||
597af815 | 4808 | ftrace_graph_active++; |
fb52607a | 4809 | ret = start_graph_tracing(); |
f201ae23 | 4810 | if (ret) { |
597af815 | 4811 | ftrace_graph_active--; |
f201ae23 FW |
4812 | goto out; |
4813 | } | |
e53a6319 | 4814 | |
287b6e68 FW |
4815 | ftrace_graph_return = retfunc; |
4816 | ftrace_graph_entry = entryfunc; | |
e53a6319 | 4817 | |
a1cd6173 | 4818 | ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET); |
e7d3737e FW |
4819 | |
4820 | out: | |
e6ea44e9 | 4821 | mutex_unlock(&ftrace_lock); |
e7d3737e | 4822 | return ret; |
15e6cb36 FW |
4823 | } |
4824 | ||
fb52607a | 4825 | void unregister_ftrace_graph(void) |
15e6cb36 | 4826 | { |
e6ea44e9 | 4827 | mutex_lock(&ftrace_lock); |
e7d3737e | 4828 | |
597af815 | 4829 | if (unlikely(!ftrace_graph_active)) |
2aad1b76 SR |
4830 | goto out; |
4831 | ||
597af815 | 4832 | ftrace_graph_active--; |
287b6e68 | 4833 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; |
e49dc19c | 4834 | ftrace_graph_entry = ftrace_graph_entry_stub; |
bd69c30b | 4835 | ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET); |
4a2b8dda | 4836 | unregister_pm_notifier(&ftrace_suspend_notifier); |
38516ab5 | 4837 | unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
e7d3737e | 4838 | |
2aad1b76 | 4839 | out: |
e6ea44e9 | 4840 | mutex_unlock(&ftrace_lock); |
15e6cb36 | 4841 | } |
f201ae23 | 4842 | |
868baf07 SR |
4843 | static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack); |
4844 | ||
4845 | static void | |
4846 | graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack) | |
4847 | { | |
4848 | atomic_set(&t->tracing_graph_pause, 0); | |
4849 | atomic_set(&t->trace_overrun, 0); | |
4850 | t->ftrace_timestamp = 0; | |
25985edc | 4851 | /* make curr_ret_stack visible before we add the ret_stack */ |
868baf07 SR |
4852 | smp_wmb(); |
4853 | t->ret_stack = ret_stack; | |
4854 | } | |
4855 | ||
4856 | /* | |
4857 | * Allocate a return stack for the idle task. May be the first | |
4858 | * time through, or it may be done by CPU hotplug online. | |
4859 | */ | |
4860 | void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) | |
4861 | { | |
4862 | t->curr_ret_stack = -1; | |
4863 | /* | |
4864 | * The idle task has no parent, it either has its own | |
4865 | * stack or no stack at all. | |
4866 | */ | |
4867 | if (t->ret_stack) | |
4868 | WARN_ON(t->ret_stack != per_cpu(idle_ret_stack, cpu)); | |
4869 | ||
4870 | if (ftrace_graph_active) { | |
4871 | struct ftrace_ret_stack *ret_stack; | |
4872 | ||
4873 | ret_stack = per_cpu(idle_ret_stack, cpu); | |
4874 | if (!ret_stack) { | |
4875 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
4876 | * sizeof(struct ftrace_ret_stack), | |
4877 | GFP_KERNEL); | |
4878 | if (!ret_stack) | |
4879 | return; | |
4880 | per_cpu(idle_ret_stack, cpu) = ret_stack; | |
4881 | } | |
4882 | graph_init_task(t, ret_stack); | |
4883 | } | |
4884 | } | |
4885 | ||
f201ae23 | 4886 | /* Allocate a return stack for newly created task */ |
fb52607a | 4887 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 4888 | { |
84047e36 SR |
4889 | /* Make sure we do not use the parent ret_stack */ |
4890 | t->ret_stack = NULL; | |
ea14eb71 | 4891 | t->curr_ret_stack = -1; |
84047e36 | 4892 | |
597af815 | 4893 | if (ftrace_graph_active) { |
82310a32 SR |
4894 | struct ftrace_ret_stack *ret_stack; |
4895 | ||
4896 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
f201ae23 FW |
4897 | * sizeof(struct ftrace_ret_stack), |
4898 | GFP_KERNEL); | |
82310a32 | 4899 | if (!ret_stack) |
f201ae23 | 4900 | return; |
868baf07 | 4901 | graph_init_task(t, ret_stack); |
84047e36 | 4902 | } |
f201ae23 FW |
4903 | } |
4904 | ||
fb52607a | 4905 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 4906 | { |
eae849ca FW |
4907 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
4908 | ||
f201ae23 | 4909 | t->ret_stack = NULL; |
eae849ca FW |
4910 | /* NULL must become visible to IRQs before we free it: */ |
4911 | barrier(); | |
4912 | ||
4913 | kfree(ret_stack); | |
f201ae23 | 4914 | } |
14a866c5 SR |
4915 | |
4916 | void ftrace_graph_stop(void) | |
4917 | { | |
4918 | ftrace_stop(); | |
4919 | } | |
15e6cb36 | 4920 | #endif |