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bcea3f96 | 1 | // SPDX-License-Identifier: GPL-2.0 |
16444a8a ACM |
2 | /* |
3 | * Infrastructure for profiling code inserted by 'gcc -pg'. | |
4 | * | |
5 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
6 | * Copyright (C) 2004-2008 Ingo Molnar <mingo@redhat.com> | |
7 | * | |
8 | * Originally ported from the -rt patch by: | |
9 | * Copyright (C) 2007 Arnaldo Carvalho de Melo <acme@redhat.com> | |
10 | * | |
11 | * Based on code in the latency_tracer, that is: | |
12 | * | |
13 | * Copyright (C) 2004-2006 Ingo Molnar | |
6d49e352 | 14 | * Copyright (C) 2004 Nadia Yvette Chambers |
16444a8a ACM |
15 | */ |
16 | ||
3d083395 SR |
17 | #include <linux/stop_machine.h> |
18 | #include <linux/clocksource.h> | |
29930025 | 19 | #include <linux/sched/task.h> |
3d083395 | 20 | #include <linux/kallsyms.h> |
17911ff3 | 21 | #include <linux/security.h> |
5072c59f | 22 | #include <linux/seq_file.h> |
8434dc93 | 23 | #include <linux/tracefs.h> |
3d083395 | 24 | #include <linux/hardirq.h> |
2d8b820b | 25 | #include <linux/kthread.h> |
5072c59f | 26 | #include <linux/uaccess.h> |
5855fead | 27 | #include <linux/bsearch.h> |
56d82e00 | 28 | #include <linux/module.h> |
2d8b820b | 29 | #include <linux/ftrace.h> |
b0fc494f | 30 | #include <linux/sysctl.h> |
5a0e3ad6 | 31 | #include <linux/slab.h> |
5072c59f | 32 | #include <linux/ctype.h> |
68950619 | 33 | #include <linux/sort.h> |
3d083395 | 34 | #include <linux/list.h> |
59df055f | 35 | #include <linux/hash.h> |
3f379b03 | 36 | #include <linux/rcupdate.h> |
fabe38ab | 37 | #include <linux/kprobes.h> |
3d083395 | 38 | |
ad8d75ff | 39 | #include <trace/events/sched.h> |
8aef2d28 | 40 | |
b80f0f6c | 41 | #include <asm/sections.h> |
2af15d6a | 42 | #include <asm/setup.h> |
395a59d0 | 43 | |
3306fc4a | 44 | #include "ftrace_internal.h" |
0706f1c4 | 45 | #include "trace_output.h" |
bac429f0 | 46 | #include "trace_stat.h" |
16444a8a | 47 | |
6912896e | 48 | #define FTRACE_WARN_ON(cond) \ |
0778d9ad SR |
49 | ({ \ |
50 | int ___r = cond; \ | |
51 | if (WARN_ON(___r)) \ | |
6912896e | 52 | ftrace_kill(); \ |
0778d9ad SR |
53 | ___r; \ |
54 | }) | |
6912896e SR |
55 | |
56 | #define FTRACE_WARN_ON_ONCE(cond) \ | |
0778d9ad SR |
57 | ({ \ |
58 | int ___r = cond; \ | |
59 | if (WARN_ON_ONCE(___r)) \ | |
6912896e | 60 | ftrace_kill(); \ |
0778d9ad SR |
61 | ___r; \ |
62 | }) | |
6912896e | 63 | |
8fc0c701 SR |
64 | /* hash bits for specific function selection */ |
65 | #define FTRACE_HASH_BITS 7 | |
66 | #define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS) | |
33dc9b12 SR |
67 | #define FTRACE_HASH_DEFAULT_BITS 10 |
68 | #define FTRACE_HASH_MAX_BITS 12 | |
8fc0c701 | 69 | |
f04f24fb | 70 | #ifdef CONFIG_DYNAMIC_FTRACE |
33b7f99c SRRH |
71 | #define INIT_OPS_HASH(opsname) \ |
72 | .func_hash = &opsname.local_hash, \ | |
73 | .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock), | |
f04f24fb | 74 | #else |
33b7f99c | 75 | #define INIT_OPS_HASH(opsname) |
f04f24fb MH |
76 | #endif |
77 | ||
a0572f68 SRV |
78 | enum { |
79 | FTRACE_MODIFY_ENABLE_FL = (1 << 0), | |
80 | FTRACE_MODIFY_MAY_SLEEP_FL = (1 << 1), | |
81 | }; | |
82 | ||
3306fc4a | 83 | struct ftrace_ops ftrace_list_end __read_mostly = { |
2f5f6ad9 | 84 | .func = ftrace_stub, |
395b97a3 | 85 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_STUB, |
33b7f99c | 86 | INIT_OPS_HASH(ftrace_list_end) |
2f5f6ad9 SR |
87 | }; |
88 | ||
4eebcc81 SR |
89 | /* ftrace_enabled is a method to turn ftrace on or off */ |
90 | int ftrace_enabled __read_mostly; | |
d61f82d0 | 91 | static int last_ftrace_enabled; |
b0fc494f | 92 | |
2f5f6ad9 SR |
93 | /* Current function tracing op */ |
94 | struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end; | |
405e1d83 SRRH |
95 | /* What to set function_trace_op to */ |
96 | static struct ftrace_ops *set_function_trace_op; | |
60a7ecf4 | 97 | |
345ddcc8 | 98 | static bool ftrace_pids_enabled(struct ftrace_ops *ops) |
e3eea140 | 99 | { |
345ddcc8 SRRH |
100 | struct trace_array *tr; |
101 | ||
102 | if (!(ops->flags & FTRACE_OPS_FL_PID) || !ops->private) | |
103 | return false; | |
104 | ||
105 | tr = ops->private; | |
106 | ||
107 | return tr->function_pids != NULL; | |
e3eea140 SRRH |
108 | } |
109 | ||
110 | static void ftrace_update_trampoline(struct ftrace_ops *ops); | |
111 | ||
4eebcc81 SR |
112 | /* |
113 | * ftrace_disabled is set when an anomaly is discovered. | |
114 | * ftrace_disabled is much stronger than ftrace_enabled. | |
115 | */ | |
116 | static int ftrace_disabled __read_mostly; | |
117 | ||
3306fc4a | 118 | DEFINE_MUTEX(ftrace_lock); |
b0fc494f | 119 | |
3306fc4a | 120 | struct ftrace_ops __rcu *ftrace_ops_list __read_mostly = &ftrace_list_end; |
16444a8a | 121 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; |
3306fc4a | 122 | struct ftrace_ops global_ops; |
16444a8a | 123 | |
2f5f6ad9 SR |
124 | #if ARCH_SUPPORTS_FTRACE_OPS |
125 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 126 | struct ftrace_ops *op, struct pt_regs *regs); |
2f5f6ad9 SR |
127 | #else |
128 | /* See comment below, where ftrace_ops_list_func is defined */ | |
129 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip); | |
130 | #define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops) | |
131 | #endif | |
b848914c | 132 | |
f04f24fb MH |
133 | static inline void ftrace_ops_init(struct ftrace_ops *ops) |
134 | { | |
135 | #ifdef CONFIG_DYNAMIC_FTRACE | |
136 | if (!(ops->flags & FTRACE_OPS_FL_INITIALIZED)) { | |
33b7f99c SRRH |
137 | mutex_init(&ops->local_hash.regex_lock); |
138 | ops->func_hash = &ops->local_hash; | |
f04f24fb MH |
139 | ops->flags |= FTRACE_OPS_FL_INITIALIZED; |
140 | } | |
141 | #endif | |
142 | } | |
143 | ||
2f5f6ad9 | 144 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 145 | struct ftrace_ops *op, struct pt_regs *regs) |
df4fc315 | 146 | { |
345ddcc8 SRRH |
147 | struct trace_array *tr = op->private; |
148 | ||
149 | if (tr && this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid)) | |
df4fc315 SR |
150 | return; |
151 | ||
e3eea140 | 152 | op->saved_func(ip, parent_ip, op, regs); |
df4fc315 SR |
153 | } |
154 | ||
405e1d83 SRRH |
155 | static void ftrace_sync(struct work_struct *work) |
156 | { | |
157 | /* | |
158 | * This function is just a stub to implement a hard force | |
74401729 | 159 | * of synchronize_rcu(). This requires synchronizing |
405e1d83 SRRH |
160 | * tasks even in userspace and idle. |
161 | * | |
162 | * Yes, function tracing is rude. | |
163 | */ | |
164 | } | |
165 | ||
166 | static void ftrace_sync_ipi(void *data) | |
167 | { | |
168 | /* Probably not needed, but do it anyway */ | |
169 | smp_rmb(); | |
170 | } | |
171 | ||
00ccbf2f SRRH |
172 | static ftrace_func_t ftrace_ops_get_list_func(struct ftrace_ops *ops) |
173 | { | |
174 | /* | |
ba27f2bc | 175 | * If this is a dynamic, RCU, or per CPU ops, or we force list func, |
00ccbf2f SRRH |
176 | * then it needs to call the list anyway. |
177 | */ | |
b3a88803 PZ |
178 | if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_RCU) || |
179 | FTRACE_FORCE_LIST_FUNC) | |
00ccbf2f SRRH |
180 | return ftrace_ops_list_func; |
181 | ||
182 | return ftrace_ops_get_func(ops); | |
183 | } | |
184 | ||
2b499381 SR |
185 | static void update_ftrace_function(void) |
186 | { | |
187 | ftrace_func_t func; | |
188 | ||
f7aad4e1 SRRH |
189 | /* |
190 | * Prepare the ftrace_ops that the arch callback will use. | |
191 | * If there's only one ftrace_ops registered, the ftrace_ops_list | |
192 | * will point to the ops we want. | |
193 | */ | |
f86f4180 CZ |
194 | set_function_trace_op = rcu_dereference_protected(ftrace_ops_list, |
195 | lockdep_is_held(&ftrace_lock)); | |
f7aad4e1 SRRH |
196 | |
197 | /* If there's no ftrace_ops registered, just call the stub function */ | |
f86f4180 | 198 | if (set_function_trace_op == &ftrace_list_end) { |
f7aad4e1 SRRH |
199 | func = ftrace_stub; |
200 | ||
cdbe61bf SR |
201 | /* |
202 | * If we are at the end of the list and this ops is | |
4740974a SR |
203 | * recursion safe and not dynamic and the arch supports passing ops, |
204 | * then have the mcount trampoline call the function directly. | |
cdbe61bf | 205 | */ |
f86f4180 CZ |
206 | } else if (rcu_dereference_protected(ftrace_ops_list->next, |
207 | lockdep_is_held(&ftrace_lock)) == &ftrace_list_end) { | |
00ccbf2f | 208 | func = ftrace_ops_get_list_func(ftrace_ops_list); |
f7aad4e1 | 209 | |
2f5f6ad9 SR |
210 | } else { |
211 | /* Just use the default ftrace_ops */ | |
405e1d83 | 212 | set_function_trace_op = &ftrace_list_end; |
b848914c | 213 | func = ftrace_ops_list_func; |
2f5f6ad9 | 214 | } |
2b499381 | 215 | |
5f8bf2d2 SRRH |
216 | update_function_graph_func(); |
217 | ||
405e1d83 SRRH |
218 | /* If there's no change, then do nothing more here */ |
219 | if (ftrace_trace_function == func) | |
220 | return; | |
221 | ||
222 | /* | |
223 | * If we are using the list function, it doesn't care | |
224 | * about the function_trace_ops. | |
225 | */ | |
226 | if (func == ftrace_ops_list_func) { | |
227 | ftrace_trace_function = func; | |
228 | /* | |
229 | * Don't even bother setting function_trace_ops, | |
230 | * it would be racy to do so anyway. | |
231 | */ | |
232 | return; | |
233 | } | |
234 | ||
235 | #ifndef CONFIG_DYNAMIC_FTRACE | |
236 | /* | |
237 | * For static tracing, we need to be a bit more careful. | |
238 | * The function change takes affect immediately. Thus, | |
239 | * we need to coorditate the setting of the function_trace_ops | |
240 | * with the setting of the ftrace_trace_function. | |
241 | * | |
242 | * Set the function to the list ops, which will call the | |
243 | * function we want, albeit indirectly, but it handles the | |
244 | * ftrace_ops and doesn't depend on function_trace_op. | |
245 | */ | |
246 | ftrace_trace_function = ftrace_ops_list_func; | |
247 | /* | |
248 | * Make sure all CPUs see this. Yes this is slow, but static | |
249 | * tracing is slow and nasty to have enabled. | |
250 | */ | |
251 | schedule_on_each_cpu(ftrace_sync); | |
252 | /* Now all cpus are using the list ops. */ | |
253 | function_trace_op = set_function_trace_op; | |
254 | /* Make sure the function_trace_op is visible on all CPUs */ | |
255 | smp_wmb(); | |
256 | /* Nasty way to force a rmb on all cpus */ | |
257 | smp_call_function(ftrace_sync_ipi, NULL, 1); | |
258 | /* OK, we are all set to update the ftrace_trace_function now! */ | |
259 | #endif /* !CONFIG_DYNAMIC_FTRACE */ | |
260 | ||
491d0dcf | 261 | ftrace_trace_function = func; |
491d0dcf SR |
262 | } |
263 | ||
f86f4180 CZ |
264 | static void add_ftrace_ops(struct ftrace_ops __rcu **list, |
265 | struct ftrace_ops *ops) | |
3d083395 | 266 | { |
f86f4180 CZ |
267 | rcu_assign_pointer(ops->next, *list); |
268 | ||
16444a8a | 269 | /* |
b848914c | 270 | * We are entering ops into the list but another |
16444a8a ACM |
271 | * CPU might be walking that list. We need to make sure |
272 | * the ops->next pointer is valid before another CPU sees | |
b848914c | 273 | * the ops pointer included into the list. |
16444a8a | 274 | */ |
2b499381 | 275 | rcu_assign_pointer(*list, ops); |
16444a8a ACM |
276 | } |
277 | ||
f86f4180 CZ |
278 | static int remove_ftrace_ops(struct ftrace_ops __rcu **list, |
279 | struct ftrace_ops *ops) | |
16444a8a | 280 | { |
16444a8a | 281 | struct ftrace_ops **p; |
16444a8a ACM |
282 | |
283 | /* | |
3d083395 SR |
284 | * If we are removing the last function, then simply point |
285 | * to the ftrace_stub. | |
16444a8a | 286 | */ |
f86f4180 CZ |
287 | if (rcu_dereference_protected(*list, |
288 | lockdep_is_held(&ftrace_lock)) == ops && | |
289 | rcu_dereference_protected(ops->next, | |
290 | lockdep_is_held(&ftrace_lock)) == &ftrace_list_end) { | |
2b499381 | 291 | *list = &ftrace_list_end; |
e6ea44e9 | 292 | return 0; |
16444a8a ACM |
293 | } |
294 | ||
2b499381 | 295 | for (p = list; *p != &ftrace_list_end; p = &(*p)->next) |
16444a8a ACM |
296 | if (*p == ops) |
297 | break; | |
298 | ||
e6ea44e9 SR |
299 | if (*p != ops) |
300 | return -1; | |
16444a8a ACM |
301 | |
302 | *p = (*p)->next; | |
2b499381 SR |
303 | return 0; |
304 | } | |
16444a8a | 305 | |
f3bea491 SRRH |
306 | static void ftrace_update_trampoline(struct ftrace_ops *ops); |
307 | ||
3306fc4a | 308 | int __register_ftrace_function(struct ftrace_ops *ops) |
2b499381 | 309 | { |
591dffda SRRH |
310 | if (ops->flags & FTRACE_OPS_FL_DELETED) |
311 | return -EINVAL; | |
312 | ||
b848914c SR |
313 | if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED)) |
314 | return -EBUSY; | |
315 | ||
06aeaaea | 316 | #ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
08f6fba5 SR |
317 | /* |
318 | * If the ftrace_ops specifies SAVE_REGS, then it only can be used | |
319 | * if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set. | |
320 | * Setting SAVE_REGS_IF_SUPPORTED makes SAVE_REGS irrelevant. | |
321 | */ | |
322 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS && | |
323 | !(ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)) | |
324 | return -EINVAL; | |
325 | ||
326 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED) | |
327 | ops->flags |= FTRACE_OPS_FL_SAVE_REGS; | |
328 | #endif | |
329 | ||
cdbe61bf SR |
330 | if (!core_kernel_data((unsigned long)ops)) |
331 | ops->flags |= FTRACE_OPS_FL_DYNAMIC; | |
332 | ||
ba27f2bc | 333 | add_ftrace_ops(&ftrace_ops_list, ops); |
b848914c | 334 | |
e3eea140 SRRH |
335 | /* Always save the function, and reset at unregistering */ |
336 | ops->saved_func = ops->func; | |
337 | ||
345ddcc8 | 338 | if (ftrace_pids_enabled(ops)) |
e3eea140 SRRH |
339 | ops->func = ftrace_pid_func; |
340 | ||
f3bea491 SRRH |
341 | ftrace_update_trampoline(ops); |
342 | ||
2b499381 SR |
343 | if (ftrace_enabled) |
344 | update_ftrace_function(); | |
345 | ||
346 | return 0; | |
347 | } | |
348 | ||
3306fc4a | 349 | int __unregister_ftrace_function(struct ftrace_ops *ops) |
2b499381 SR |
350 | { |
351 | int ret; | |
352 | ||
b848914c SR |
353 | if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) |
354 | return -EBUSY; | |
355 | ||
ba27f2bc | 356 | ret = remove_ftrace_ops(&ftrace_ops_list, ops); |
b848914c | 357 | |
2b499381 SR |
358 | if (ret < 0) |
359 | return ret; | |
b848914c | 360 | |
491d0dcf SR |
361 | if (ftrace_enabled) |
362 | update_ftrace_function(); | |
16444a8a | 363 | |
e3eea140 SRRH |
364 | ops->func = ops->saved_func; |
365 | ||
e6ea44e9 | 366 | return 0; |
3d083395 SR |
367 | } |
368 | ||
df4fc315 SR |
369 | static void ftrace_update_pid_func(void) |
370 | { | |
e3eea140 SRRH |
371 | struct ftrace_ops *op; |
372 | ||
491d0dcf | 373 | /* Only do something if we are tracing something */ |
df4fc315 | 374 | if (ftrace_trace_function == ftrace_stub) |
10dd3ebe | 375 | return; |
df4fc315 | 376 | |
e3eea140 SRRH |
377 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
378 | if (op->flags & FTRACE_OPS_FL_PID) { | |
345ddcc8 SRRH |
379 | op->func = ftrace_pids_enabled(op) ? |
380 | ftrace_pid_func : op->saved_func; | |
e3eea140 SRRH |
381 | ftrace_update_trampoline(op); |
382 | } | |
383 | } while_for_each_ftrace_op(op); | |
384 | ||
491d0dcf | 385 | update_ftrace_function(); |
df4fc315 SR |
386 | } |
387 | ||
493762fc SR |
388 | #ifdef CONFIG_FUNCTION_PROFILER |
389 | struct ftrace_profile { | |
390 | struct hlist_node node; | |
391 | unsigned long ip; | |
392 | unsigned long counter; | |
0706f1c4 SR |
393 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
394 | unsigned long long time; | |
e330b3bc | 395 | unsigned long long time_squared; |
0706f1c4 | 396 | #endif |
8fc0c701 SR |
397 | }; |
398 | ||
493762fc SR |
399 | struct ftrace_profile_page { |
400 | struct ftrace_profile_page *next; | |
401 | unsigned long index; | |
402 | struct ftrace_profile records[]; | |
d61f82d0 SR |
403 | }; |
404 | ||
cafb168a SR |
405 | struct ftrace_profile_stat { |
406 | atomic_t disabled; | |
407 | struct hlist_head *hash; | |
408 | struct ftrace_profile_page *pages; | |
409 | struct ftrace_profile_page *start; | |
410 | struct tracer_stat stat; | |
411 | }; | |
412 | ||
493762fc SR |
413 | #define PROFILE_RECORDS_SIZE \ |
414 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | |
5072c59f | 415 | |
493762fc SR |
416 | #define PROFILES_PER_PAGE \ |
417 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | |
3d083395 | 418 | |
fb9fb015 SR |
419 | static int ftrace_profile_enabled __read_mostly; |
420 | ||
421 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ | |
bac429f0 SR |
422 | static DEFINE_MUTEX(ftrace_profile_lock); |
423 | ||
cafb168a | 424 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); |
493762fc | 425 | |
20079ebe NK |
426 | #define FTRACE_PROFILE_HASH_BITS 10 |
427 | #define FTRACE_PROFILE_HASH_SIZE (1 << FTRACE_PROFILE_HASH_BITS) | |
493762fc | 428 | |
bac429f0 SR |
429 | static void * |
430 | function_stat_next(void *v, int idx) | |
431 | { | |
493762fc SR |
432 | struct ftrace_profile *rec = v; |
433 | struct ftrace_profile_page *pg; | |
bac429f0 | 434 | |
493762fc | 435 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
bac429f0 SR |
436 | |
437 | again: | |
0296e425 LZ |
438 | if (idx != 0) |
439 | rec++; | |
440 | ||
bac429f0 SR |
441 | if ((void *)rec >= (void *)&pg->records[pg->index]) { |
442 | pg = pg->next; | |
443 | if (!pg) | |
444 | return NULL; | |
445 | rec = &pg->records[0]; | |
493762fc SR |
446 | if (!rec->counter) |
447 | goto again; | |
bac429f0 SR |
448 | } |
449 | ||
bac429f0 SR |
450 | return rec; |
451 | } | |
452 | ||
453 | static void *function_stat_start(struct tracer_stat *trace) | |
454 | { | |
cafb168a SR |
455 | struct ftrace_profile_stat *stat = |
456 | container_of(trace, struct ftrace_profile_stat, stat); | |
457 | ||
458 | if (!stat || !stat->start) | |
459 | return NULL; | |
460 | ||
461 | return function_stat_next(&stat->start->records[0], 0); | |
bac429f0 SR |
462 | } |
463 | ||
0706f1c4 SR |
464 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
465 | /* function graph compares on total time */ | |
466 | static int function_stat_cmp(void *p1, void *p2) | |
467 | { | |
468 | struct ftrace_profile *a = p1; | |
469 | struct ftrace_profile *b = p2; | |
470 | ||
471 | if (a->time < b->time) | |
472 | return -1; | |
473 | if (a->time > b->time) | |
474 | return 1; | |
475 | else | |
476 | return 0; | |
477 | } | |
478 | #else | |
479 | /* not function graph compares against hits */ | |
bac429f0 SR |
480 | static int function_stat_cmp(void *p1, void *p2) |
481 | { | |
493762fc SR |
482 | struct ftrace_profile *a = p1; |
483 | struct ftrace_profile *b = p2; | |
bac429f0 SR |
484 | |
485 | if (a->counter < b->counter) | |
486 | return -1; | |
487 | if (a->counter > b->counter) | |
488 | return 1; | |
489 | else | |
490 | return 0; | |
491 | } | |
0706f1c4 | 492 | #endif |
bac429f0 SR |
493 | |
494 | static int function_stat_headers(struct seq_file *m) | |
495 | { | |
0706f1c4 | 496 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
fa6f0cc7 RV |
497 | seq_puts(m, " Function " |
498 | "Hit Time Avg s^2\n" | |
499 | " -------- " | |
500 | "--- ---- --- ---\n"); | |
0706f1c4 | 501 | #else |
fa6f0cc7 RV |
502 | seq_puts(m, " Function Hit\n" |
503 | " -------- ---\n"); | |
0706f1c4 | 504 | #endif |
bac429f0 SR |
505 | return 0; |
506 | } | |
507 | ||
508 | static int function_stat_show(struct seq_file *m, void *v) | |
509 | { | |
493762fc | 510 | struct ftrace_profile *rec = v; |
bac429f0 | 511 | char str[KSYM_SYMBOL_LEN]; |
3aaba20f | 512 | int ret = 0; |
0706f1c4 | 513 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b SR |
514 | static struct trace_seq s; |
515 | unsigned long long avg; | |
e330b3bc | 516 | unsigned long long stddev; |
0706f1c4 | 517 | #endif |
3aaba20f LZ |
518 | mutex_lock(&ftrace_profile_lock); |
519 | ||
520 | /* we raced with function_profile_reset() */ | |
521 | if (unlikely(rec->counter == 0)) { | |
522 | ret = -EBUSY; | |
523 | goto out; | |
524 | } | |
bac429f0 | 525 | |
8e436ca0 | 526 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
86fad0f1 | 527 | avg = div64_ul(rec->time, rec->counter); |
8e436ca0 UT |
528 | if (tracing_thresh && (avg < tracing_thresh)) |
529 | goto out; | |
530 | #endif | |
531 | ||
bac429f0 | 532 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); |
0706f1c4 SR |
533 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); |
534 | ||
535 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
fa6f0cc7 | 536 | seq_puts(m, " "); |
34886c8b | 537 | |
e330b3bc CD |
538 | /* Sample standard deviation (s^2) */ |
539 | if (rec->counter <= 1) | |
540 | stddev = 0; | |
541 | else { | |
52d85d76 JL |
542 | /* |
543 | * Apply Welford's method: | |
544 | * s^2 = 1 / (n * (n-1)) * (n * \Sum (x_i)^2 - (\Sum x_i)^2) | |
545 | */ | |
546 | stddev = rec->counter * rec->time_squared - | |
547 | rec->time * rec->time; | |
548 | ||
e330b3bc CD |
549 | /* |
550 | * Divide only 1000 for ns^2 -> us^2 conversion. | |
551 | * trace_print_graph_duration will divide 1000 again. | |
552 | */ | |
86fad0f1 WY |
553 | stddev = div64_ul(stddev, |
554 | rec->counter * (rec->counter - 1) * 1000); | |
e330b3bc CD |
555 | } |
556 | ||
34886c8b SR |
557 | trace_seq_init(&s); |
558 | trace_print_graph_duration(rec->time, &s); | |
559 | trace_seq_puts(&s, " "); | |
560 | trace_print_graph_duration(avg, &s); | |
e330b3bc CD |
561 | trace_seq_puts(&s, " "); |
562 | trace_print_graph_duration(stddev, &s); | |
0706f1c4 | 563 | trace_print_seq(m, &s); |
0706f1c4 SR |
564 | #endif |
565 | seq_putc(m, '\n'); | |
3aaba20f LZ |
566 | out: |
567 | mutex_unlock(&ftrace_profile_lock); | |
bac429f0 | 568 | |
3aaba20f | 569 | return ret; |
bac429f0 SR |
570 | } |
571 | ||
cafb168a | 572 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) |
bac429f0 | 573 | { |
493762fc | 574 | struct ftrace_profile_page *pg; |
bac429f0 | 575 | |
cafb168a | 576 | pg = stat->pages = stat->start; |
bac429f0 | 577 | |
493762fc SR |
578 | while (pg) { |
579 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | |
580 | pg->index = 0; | |
581 | pg = pg->next; | |
bac429f0 SR |
582 | } |
583 | ||
cafb168a | 584 | memset(stat->hash, 0, |
493762fc SR |
585 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); |
586 | } | |
bac429f0 | 587 | |
cafb168a | 588 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) |
493762fc SR |
589 | { |
590 | struct ftrace_profile_page *pg; | |
318e0a73 SR |
591 | int functions; |
592 | int pages; | |
493762fc | 593 | int i; |
bac429f0 | 594 | |
493762fc | 595 | /* If we already allocated, do nothing */ |
cafb168a | 596 | if (stat->pages) |
493762fc | 597 | return 0; |
bac429f0 | 598 | |
cafb168a SR |
599 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); |
600 | if (!stat->pages) | |
493762fc | 601 | return -ENOMEM; |
bac429f0 | 602 | |
318e0a73 SR |
603 | #ifdef CONFIG_DYNAMIC_FTRACE |
604 | functions = ftrace_update_tot_cnt; | |
605 | #else | |
606 | /* | |
607 | * We do not know the number of functions that exist because | |
608 | * dynamic tracing is what counts them. With past experience | |
609 | * we have around 20K functions. That should be more than enough. | |
610 | * It is highly unlikely we will execute every function in | |
611 | * the kernel. | |
612 | */ | |
613 | functions = 20000; | |
614 | #endif | |
615 | ||
cafb168a | 616 | pg = stat->start = stat->pages; |
bac429f0 | 617 | |
318e0a73 SR |
618 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); |
619 | ||
39e30cd1 | 620 | for (i = 1; i < pages; i++) { |
493762fc | 621 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
493762fc | 622 | if (!pg->next) |
318e0a73 | 623 | goto out_free; |
493762fc SR |
624 | pg = pg->next; |
625 | } | |
626 | ||
627 | return 0; | |
318e0a73 SR |
628 | |
629 | out_free: | |
630 | pg = stat->start; | |
631 | while (pg) { | |
632 | unsigned long tmp = (unsigned long)pg; | |
633 | ||
634 | pg = pg->next; | |
635 | free_page(tmp); | |
636 | } | |
637 | ||
318e0a73 SR |
638 | stat->pages = NULL; |
639 | stat->start = NULL; | |
640 | ||
641 | return -ENOMEM; | |
bac429f0 SR |
642 | } |
643 | ||
cafb168a | 644 | static int ftrace_profile_init_cpu(int cpu) |
bac429f0 | 645 | { |
cafb168a | 646 | struct ftrace_profile_stat *stat; |
493762fc | 647 | int size; |
bac429f0 | 648 | |
cafb168a SR |
649 | stat = &per_cpu(ftrace_profile_stats, cpu); |
650 | ||
651 | if (stat->hash) { | |
493762fc | 652 | /* If the profile is already created, simply reset it */ |
cafb168a | 653 | ftrace_profile_reset(stat); |
493762fc SR |
654 | return 0; |
655 | } | |
bac429f0 | 656 | |
493762fc SR |
657 | /* |
658 | * We are profiling all functions, but usually only a few thousand | |
659 | * functions are hit. We'll make a hash of 1024 items. | |
660 | */ | |
661 | size = FTRACE_PROFILE_HASH_SIZE; | |
bac429f0 | 662 | |
6396bb22 | 663 | stat->hash = kcalloc(size, sizeof(struct hlist_head), GFP_KERNEL); |
493762fc | 664 | |
cafb168a | 665 | if (!stat->hash) |
493762fc SR |
666 | return -ENOMEM; |
667 | ||
318e0a73 | 668 | /* Preallocate the function profiling pages */ |
cafb168a SR |
669 | if (ftrace_profile_pages_init(stat) < 0) { |
670 | kfree(stat->hash); | |
671 | stat->hash = NULL; | |
493762fc SR |
672 | return -ENOMEM; |
673 | } | |
674 | ||
675 | return 0; | |
bac429f0 SR |
676 | } |
677 | ||
cafb168a SR |
678 | static int ftrace_profile_init(void) |
679 | { | |
680 | int cpu; | |
681 | int ret = 0; | |
682 | ||
c4602c1c | 683 | for_each_possible_cpu(cpu) { |
cafb168a SR |
684 | ret = ftrace_profile_init_cpu(cpu); |
685 | if (ret) | |
686 | break; | |
687 | } | |
688 | ||
689 | return ret; | |
690 | } | |
691 | ||
493762fc | 692 | /* interrupts must be disabled */ |
cafb168a SR |
693 | static struct ftrace_profile * |
694 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) | |
bac429f0 | 695 | { |
493762fc | 696 | struct ftrace_profile *rec; |
bac429f0 | 697 | struct hlist_head *hhd; |
bac429f0 SR |
698 | unsigned long key; |
699 | ||
20079ebe | 700 | key = hash_long(ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 701 | hhd = &stat->hash[key]; |
bac429f0 SR |
702 | |
703 | if (hlist_empty(hhd)) | |
704 | return NULL; | |
705 | ||
1bb539ca | 706 | hlist_for_each_entry_rcu_notrace(rec, hhd, node) { |
bac429f0 | 707 | if (rec->ip == ip) |
493762fc SR |
708 | return rec; |
709 | } | |
710 | ||
711 | return NULL; | |
712 | } | |
713 | ||
cafb168a SR |
714 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, |
715 | struct ftrace_profile *rec) | |
493762fc SR |
716 | { |
717 | unsigned long key; | |
718 | ||
20079ebe | 719 | key = hash_long(rec->ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 720 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); |
493762fc SR |
721 | } |
722 | ||
318e0a73 SR |
723 | /* |
724 | * The memory is already allocated, this simply finds a new record to use. | |
725 | */ | |
493762fc | 726 | static struct ftrace_profile * |
318e0a73 | 727 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) |
493762fc SR |
728 | { |
729 | struct ftrace_profile *rec = NULL; | |
730 | ||
318e0a73 | 731 | /* prevent recursion (from NMIs) */ |
cafb168a | 732 | if (atomic_inc_return(&stat->disabled) != 1) |
493762fc SR |
733 | goto out; |
734 | ||
493762fc | 735 | /* |
318e0a73 SR |
736 | * Try to find the function again since an NMI |
737 | * could have added it | |
493762fc | 738 | */ |
cafb168a | 739 | rec = ftrace_find_profiled_func(stat, ip); |
493762fc | 740 | if (rec) |
cafb168a | 741 | goto out; |
493762fc | 742 | |
cafb168a SR |
743 | if (stat->pages->index == PROFILES_PER_PAGE) { |
744 | if (!stat->pages->next) | |
745 | goto out; | |
746 | stat->pages = stat->pages->next; | |
bac429f0 | 747 | } |
493762fc | 748 | |
cafb168a | 749 | rec = &stat->pages->records[stat->pages->index++]; |
493762fc | 750 | rec->ip = ip; |
cafb168a | 751 | ftrace_add_profile(stat, rec); |
493762fc | 752 | |
bac429f0 | 753 | out: |
cafb168a | 754 | atomic_dec(&stat->disabled); |
bac429f0 SR |
755 | |
756 | return rec; | |
757 | } | |
758 | ||
759 | static void | |
2f5f6ad9 | 760 | function_profile_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 761 | struct ftrace_ops *ops, struct pt_regs *regs) |
bac429f0 | 762 | { |
cafb168a | 763 | struct ftrace_profile_stat *stat; |
493762fc | 764 | struct ftrace_profile *rec; |
bac429f0 SR |
765 | unsigned long flags; |
766 | ||
767 | if (!ftrace_profile_enabled) | |
768 | return; | |
769 | ||
770 | local_irq_save(flags); | |
cafb168a | 771 | |
bdffd893 | 772 | stat = this_cpu_ptr(&ftrace_profile_stats); |
0f6ce3de | 773 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
774 | goto out; |
775 | ||
776 | rec = ftrace_find_profiled_func(stat, ip); | |
493762fc | 777 | if (!rec) { |
318e0a73 | 778 | rec = ftrace_profile_alloc(stat, ip); |
493762fc SR |
779 | if (!rec) |
780 | goto out; | |
781 | } | |
bac429f0 SR |
782 | |
783 | rec->counter++; | |
784 | out: | |
785 | local_irq_restore(flags); | |
786 | } | |
787 | ||
0706f1c4 | 788 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e73e679f SRV |
789 | static bool fgraph_graph_time = true; |
790 | ||
791 | void ftrace_graph_graph_time_control(bool enable) | |
792 | { | |
793 | fgraph_graph_time = enable; | |
794 | } | |
795 | ||
0706f1c4 SR |
796 | static int profile_graph_entry(struct ftrace_graph_ent *trace) |
797 | { | |
b0e21a61 | 798 | struct ftrace_ret_stack *ret_stack; |
8861dd30 | 799 | |
a1e2e31d | 800 | function_profile_call(trace->func, 0, NULL, NULL); |
8861dd30 | 801 | |
a8f0f9e4 SRV |
802 | /* If function graph is shutting down, ret_stack can be NULL */ |
803 | if (!current->ret_stack) | |
804 | return 0; | |
805 | ||
b0e21a61 SRV |
806 | ret_stack = ftrace_graph_get_ret_stack(current, 0); |
807 | if (ret_stack) | |
808 | ret_stack->subtime = 0; | |
8861dd30 | 809 | |
0706f1c4 SR |
810 | return 1; |
811 | } | |
812 | ||
813 | static void profile_graph_return(struct ftrace_graph_ret *trace) | |
814 | { | |
b0e21a61 | 815 | struct ftrace_ret_stack *ret_stack; |
cafb168a | 816 | struct ftrace_profile_stat *stat; |
a2a16d6a | 817 | unsigned long long calltime; |
0706f1c4 | 818 | struct ftrace_profile *rec; |
cafb168a | 819 | unsigned long flags; |
0706f1c4 SR |
820 | |
821 | local_irq_save(flags); | |
bdffd893 | 822 | stat = this_cpu_ptr(&ftrace_profile_stats); |
0f6ce3de | 823 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
824 | goto out; |
825 | ||
37e44bc5 SR |
826 | /* If the calltime was zero'd ignore it */ |
827 | if (!trace->calltime) | |
828 | goto out; | |
829 | ||
a2a16d6a SR |
830 | calltime = trace->rettime - trace->calltime; |
831 | ||
55577204 | 832 | if (!fgraph_graph_time) { |
a2a16d6a SR |
833 | |
834 | /* Append this call time to the parent time to subtract */ | |
b0e21a61 SRV |
835 | ret_stack = ftrace_graph_get_ret_stack(current, 1); |
836 | if (ret_stack) | |
837 | ret_stack->subtime += calltime; | |
a2a16d6a | 838 | |
b0e21a61 SRV |
839 | ret_stack = ftrace_graph_get_ret_stack(current, 0); |
840 | if (ret_stack && ret_stack->subtime < calltime) | |
841 | calltime -= ret_stack->subtime; | |
a2a16d6a SR |
842 | else |
843 | calltime = 0; | |
844 | } | |
845 | ||
cafb168a | 846 | rec = ftrace_find_profiled_func(stat, trace->func); |
e330b3bc | 847 | if (rec) { |
a2a16d6a | 848 | rec->time += calltime; |
e330b3bc CD |
849 | rec->time_squared += calltime * calltime; |
850 | } | |
a2a16d6a | 851 | |
cafb168a | 852 | out: |
0706f1c4 SR |
853 | local_irq_restore(flags); |
854 | } | |
855 | ||
688f7089 SRV |
856 | static struct fgraph_ops fprofiler_ops = { |
857 | .entryfunc = &profile_graph_entry, | |
858 | .retfunc = &profile_graph_return, | |
859 | }; | |
860 | ||
0706f1c4 SR |
861 | static int register_ftrace_profiler(void) |
862 | { | |
688f7089 | 863 | return register_ftrace_graph(&fprofiler_ops); |
0706f1c4 SR |
864 | } |
865 | ||
866 | static void unregister_ftrace_profiler(void) | |
867 | { | |
688f7089 | 868 | unregister_ftrace_graph(&fprofiler_ops); |
0706f1c4 SR |
869 | } |
870 | #else | |
bd38c0e6 | 871 | static struct ftrace_ops ftrace_profile_ops __read_mostly = { |
fb9fb015 | 872 | .func = function_profile_call, |
f04f24fb | 873 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, |
33b7f99c | 874 | INIT_OPS_HASH(ftrace_profile_ops) |
bac429f0 SR |
875 | }; |
876 | ||
0706f1c4 SR |
877 | static int register_ftrace_profiler(void) |
878 | { | |
879 | return register_ftrace_function(&ftrace_profile_ops); | |
880 | } | |
881 | ||
882 | static void unregister_ftrace_profiler(void) | |
883 | { | |
884 | unregister_ftrace_function(&ftrace_profile_ops); | |
885 | } | |
886 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
887 | ||
bac429f0 SR |
888 | static ssize_t |
889 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | |
890 | size_t cnt, loff_t *ppos) | |
891 | { | |
892 | unsigned long val; | |
bac429f0 SR |
893 | int ret; |
894 | ||
22fe9b54 PH |
895 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
896 | if (ret) | |
bac429f0 SR |
897 | return ret; |
898 | ||
899 | val = !!val; | |
900 | ||
901 | mutex_lock(&ftrace_profile_lock); | |
902 | if (ftrace_profile_enabled ^ val) { | |
903 | if (val) { | |
493762fc SR |
904 | ret = ftrace_profile_init(); |
905 | if (ret < 0) { | |
906 | cnt = ret; | |
907 | goto out; | |
908 | } | |
909 | ||
0706f1c4 SR |
910 | ret = register_ftrace_profiler(); |
911 | if (ret < 0) { | |
912 | cnt = ret; | |
913 | goto out; | |
914 | } | |
bac429f0 SR |
915 | ftrace_profile_enabled = 1; |
916 | } else { | |
917 | ftrace_profile_enabled = 0; | |
0f6ce3de SR |
918 | /* |
919 | * unregister_ftrace_profiler calls stop_machine | |
74401729 | 920 | * so this acts like an synchronize_rcu. |
0f6ce3de | 921 | */ |
0706f1c4 | 922 | unregister_ftrace_profiler(); |
bac429f0 SR |
923 | } |
924 | } | |
493762fc | 925 | out: |
bac429f0 SR |
926 | mutex_unlock(&ftrace_profile_lock); |
927 | ||
cf8517cf | 928 | *ppos += cnt; |
bac429f0 SR |
929 | |
930 | return cnt; | |
931 | } | |
932 | ||
493762fc SR |
933 | static ssize_t |
934 | ftrace_profile_read(struct file *filp, char __user *ubuf, | |
935 | size_t cnt, loff_t *ppos) | |
936 | { | |
fb9fb015 | 937 | char buf[64]; /* big enough to hold a number */ |
493762fc SR |
938 | int r; |
939 | ||
940 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | |
941 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
942 | } | |
943 | ||
bac429f0 SR |
944 | static const struct file_operations ftrace_profile_fops = { |
945 | .open = tracing_open_generic, | |
946 | .read = ftrace_profile_read, | |
947 | .write = ftrace_profile_write, | |
6038f373 | 948 | .llseek = default_llseek, |
bac429f0 SR |
949 | }; |
950 | ||
cafb168a SR |
951 | /* used to initialize the real stat files */ |
952 | static struct tracer_stat function_stats __initdata = { | |
fb9fb015 SR |
953 | .name = "functions", |
954 | .stat_start = function_stat_start, | |
955 | .stat_next = function_stat_next, | |
956 | .stat_cmp = function_stat_cmp, | |
957 | .stat_headers = function_stat_headers, | |
958 | .stat_show = function_stat_show | |
cafb168a SR |
959 | }; |
960 | ||
8434dc93 | 961 | static __init void ftrace_profile_tracefs(struct dentry *d_tracer) |
bac429f0 | 962 | { |
cafb168a | 963 | struct ftrace_profile_stat *stat; |
bac429f0 | 964 | struct dentry *entry; |
cafb168a | 965 | char *name; |
bac429f0 | 966 | int ret; |
cafb168a SR |
967 | int cpu; |
968 | ||
969 | for_each_possible_cpu(cpu) { | |
970 | stat = &per_cpu(ftrace_profile_stats, cpu); | |
971 | ||
6363c6b5 | 972 | name = kasprintf(GFP_KERNEL, "function%d", cpu); |
cafb168a SR |
973 | if (!name) { |
974 | /* | |
975 | * The files created are permanent, if something happens | |
976 | * we still do not free memory. | |
977 | */ | |
cafb168a SR |
978 | WARN(1, |
979 | "Could not allocate stat file for cpu %d\n", | |
980 | cpu); | |
981 | return; | |
982 | } | |
983 | stat->stat = function_stats; | |
cafb168a SR |
984 | stat->stat.name = name; |
985 | ret = register_stat_tracer(&stat->stat); | |
986 | if (ret) { | |
987 | WARN(1, | |
988 | "Could not register function stat for cpu %d\n", | |
989 | cpu); | |
990 | kfree(name); | |
991 | return; | |
992 | } | |
bac429f0 SR |
993 | } |
994 | ||
8434dc93 | 995 | entry = tracefs_create_file("function_profile_enabled", 0644, |
bac429f0 SR |
996 | d_tracer, NULL, &ftrace_profile_fops); |
997 | if (!entry) | |
a395d6a7 | 998 | pr_warn("Could not create tracefs 'function_profile_enabled' entry\n"); |
bac429f0 SR |
999 | } |
1000 | ||
bac429f0 | 1001 | #else /* CONFIG_FUNCTION_PROFILER */ |
8434dc93 | 1002 | static __init void ftrace_profile_tracefs(struct dentry *d_tracer) |
bac429f0 SR |
1003 | { |
1004 | } | |
bac429f0 SR |
1005 | #endif /* CONFIG_FUNCTION_PROFILER */ |
1006 | ||
493762fc SR |
1007 | #ifdef CONFIG_DYNAMIC_FTRACE |
1008 | ||
79922b80 SRRH |
1009 | static struct ftrace_ops *removed_ops; |
1010 | ||
e1effa01 SRRH |
1011 | /* |
1012 | * Set when doing a global update, like enabling all recs or disabling them. | |
1013 | * It is not set when just updating a single ftrace_ops. | |
1014 | */ | |
1015 | static bool update_all_ops; | |
1016 | ||
493762fc SR |
1017 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD |
1018 | # error Dynamic ftrace depends on MCOUNT_RECORD | |
1019 | #endif | |
1020 | ||
b448c4e3 SR |
1021 | struct ftrace_func_entry { |
1022 | struct hlist_node hlist; | |
1023 | unsigned long ip; | |
1024 | }; | |
1025 | ||
7b60f3d8 SRV |
1026 | struct ftrace_func_probe { |
1027 | struct ftrace_probe_ops *probe_ops; | |
1028 | struct ftrace_ops ops; | |
1029 | struct trace_array *tr; | |
1030 | struct list_head list; | |
6e444319 | 1031 | void *data; |
7b60f3d8 SRV |
1032 | int ref; |
1033 | }; | |
1034 | ||
33dc9b12 SR |
1035 | /* |
1036 | * We make these constant because no one should touch them, | |
1037 | * but they are used as the default "empty hash", to avoid allocating | |
1038 | * it all the time. These are in a read only section such that if | |
1039 | * anyone does try to modify it, it will cause an exception. | |
1040 | */ | |
1041 | static const struct hlist_head empty_buckets[1]; | |
1042 | static const struct ftrace_hash empty_hash = { | |
1043 | .buckets = (struct hlist_head *)empty_buckets, | |
1cf41dd7 | 1044 | }; |
33dc9b12 | 1045 | #define EMPTY_HASH ((struct ftrace_hash *)&empty_hash) |
493762fc | 1046 | |
3306fc4a | 1047 | struct ftrace_ops global_ops = { |
33b7f99c SRRH |
1048 | .func = ftrace_stub, |
1049 | .local_hash.notrace_hash = EMPTY_HASH, | |
1050 | .local_hash.filter_hash = EMPTY_HASH, | |
1051 | INIT_OPS_HASH(global_ops) | |
1052 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | | |
e3eea140 SRRH |
1053 | FTRACE_OPS_FL_INITIALIZED | |
1054 | FTRACE_OPS_FL_PID, | |
f45948e8 SR |
1055 | }; |
1056 | ||
aec0be2d | 1057 | /* |
6be7fa3c | 1058 | * Used by the stack undwinder to know about dynamic ftrace trampolines. |
aec0be2d | 1059 | */ |
6be7fa3c | 1060 | struct ftrace_ops *ftrace_ops_trampoline(unsigned long addr) |
aec0be2d | 1061 | { |
6be7fa3c | 1062 | struct ftrace_ops *op = NULL; |
aec0be2d SRRH |
1063 | |
1064 | /* | |
1065 | * Some of the ops may be dynamically allocated, | |
74401729 | 1066 | * they are freed after a synchronize_rcu(). |
aec0be2d SRRH |
1067 | */ |
1068 | preempt_disable_notrace(); | |
1069 | ||
1070 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
1071 | /* | |
1072 | * This is to check for dynamically allocated trampolines. | |
1073 | * Trampolines that are in kernel text will have | |
1074 | * core_kernel_text() return true. | |
1075 | */ | |
1076 | if (op->trampoline && op->trampoline_size) | |
1077 | if (addr >= op->trampoline && | |
1078 | addr < op->trampoline + op->trampoline_size) { | |
6be7fa3c SRV |
1079 | preempt_enable_notrace(); |
1080 | return op; | |
aec0be2d SRRH |
1081 | } |
1082 | } while_for_each_ftrace_op(op); | |
aec0be2d SRRH |
1083 | preempt_enable_notrace(); |
1084 | ||
6be7fa3c SRV |
1085 | return NULL; |
1086 | } | |
1087 | ||
1088 | /* | |
1089 | * This is used by __kernel_text_address() to return true if the | |
1090 | * address is on a dynamically allocated trampoline that would | |
1091 | * not return true for either core_kernel_text() or | |
1092 | * is_module_text_address(). | |
1093 | */ | |
1094 | bool is_ftrace_trampoline(unsigned long addr) | |
1095 | { | |
1096 | return ftrace_ops_trampoline(addr) != NULL; | |
aec0be2d SRRH |
1097 | } |
1098 | ||
493762fc SR |
1099 | struct ftrace_page { |
1100 | struct ftrace_page *next; | |
a7900875 | 1101 | struct dyn_ftrace *records; |
493762fc | 1102 | int index; |
a7900875 | 1103 | int size; |
493762fc SR |
1104 | }; |
1105 | ||
a7900875 SR |
1106 | #define ENTRY_SIZE sizeof(struct dyn_ftrace) |
1107 | #define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE) | |
493762fc SR |
1108 | |
1109 | /* estimate from running different kernels */ | |
1110 | #define NR_TO_INIT 10000 | |
1111 | ||
1112 | static struct ftrace_page *ftrace_pages_start; | |
1113 | static struct ftrace_page *ftrace_pages; | |
1114 | ||
2b0cce0e SRV |
1115 | static __always_inline unsigned long |
1116 | ftrace_hash_key(struct ftrace_hash *hash, unsigned long ip) | |
1117 | { | |
1118 | if (hash->size_bits > 0) | |
1119 | return hash_long(ip, hash->size_bits); | |
1120 | ||
1121 | return 0; | |
1122 | } | |
1123 | ||
2b2c279c SRV |
1124 | /* Only use this function if ftrace_hash_empty() has already been tested */ |
1125 | static __always_inline struct ftrace_func_entry * | |
1126 | __ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
b448c4e3 SR |
1127 | { |
1128 | unsigned long key; | |
1129 | struct ftrace_func_entry *entry; | |
1130 | struct hlist_head *hhd; | |
b448c4e3 | 1131 | |
2b0cce0e | 1132 | key = ftrace_hash_key(hash, ip); |
b448c4e3 SR |
1133 | hhd = &hash->buckets[key]; |
1134 | ||
1bb539ca | 1135 | hlist_for_each_entry_rcu_notrace(entry, hhd, hlist) { |
b448c4e3 SR |
1136 | if (entry->ip == ip) |
1137 | return entry; | |
1138 | } | |
1139 | return NULL; | |
1140 | } | |
1141 | ||
2b2c279c SRV |
1142 | /** |
1143 | * ftrace_lookup_ip - Test to see if an ip exists in an ftrace_hash | |
1144 | * @hash: The hash to look at | |
1145 | * @ip: The instruction pointer to test | |
1146 | * | |
1147 | * Search a given @hash to see if a given instruction pointer (@ip) | |
1148 | * exists in it. | |
1149 | * | |
1150 | * Returns the entry that holds the @ip if found. NULL otherwise. | |
1151 | */ | |
1152 | struct ftrace_func_entry * | |
1153 | ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
1154 | { | |
1155 | if (ftrace_hash_empty(hash)) | |
1156 | return NULL; | |
1157 | ||
1158 | return __ftrace_lookup_ip(hash, ip); | |
1159 | } | |
1160 | ||
33dc9b12 SR |
1161 | static void __add_hash_entry(struct ftrace_hash *hash, |
1162 | struct ftrace_func_entry *entry) | |
b448c4e3 | 1163 | { |
b448c4e3 SR |
1164 | struct hlist_head *hhd; |
1165 | unsigned long key; | |
1166 | ||
2b0cce0e | 1167 | key = ftrace_hash_key(hash, entry->ip); |
b448c4e3 SR |
1168 | hhd = &hash->buckets[key]; |
1169 | hlist_add_head(&entry->hlist, hhd); | |
1170 | hash->count++; | |
33dc9b12 SR |
1171 | } |
1172 | ||
1173 | static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) | |
1174 | { | |
1175 | struct ftrace_func_entry *entry; | |
1176 | ||
1177 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
1178 | if (!entry) | |
1179 | return -ENOMEM; | |
1180 | ||
1181 | entry->ip = ip; | |
1182 | __add_hash_entry(hash, entry); | |
b448c4e3 SR |
1183 | |
1184 | return 0; | |
1185 | } | |
1186 | ||
1187 | static void | |
33dc9b12 | 1188 | free_hash_entry(struct ftrace_hash *hash, |
b448c4e3 SR |
1189 | struct ftrace_func_entry *entry) |
1190 | { | |
1191 | hlist_del(&entry->hlist); | |
1192 | kfree(entry); | |
1193 | hash->count--; | |
1194 | } | |
1195 | ||
33dc9b12 SR |
1196 | static void |
1197 | remove_hash_entry(struct ftrace_hash *hash, | |
1198 | struct ftrace_func_entry *entry) | |
1199 | { | |
eee8ded1 | 1200 | hlist_del_rcu(&entry->hlist); |
33dc9b12 SR |
1201 | hash->count--; |
1202 | } | |
1203 | ||
b448c4e3 SR |
1204 | static void ftrace_hash_clear(struct ftrace_hash *hash) |
1205 | { | |
1206 | struct hlist_head *hhd; | |
b67bfe0d | 1207 | struct hlist_node *tn; |
b448c4e3 SR |
1208 | struct ftrace_func_entry *entry; |
1209 | int size = 1 << hash->size_bits; | |
1210 | int i; | |
1211 | ||
33dc9b12 SR |
1212 | if (!hash->count) |
1213 | return; | |
1214 | ||
b448c4e3 SR |
1215 | for (i = 0; i < size; i++) { |
1216 | hhd = &hash->buckets[i]; | |
b67bfe0d | 1217 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) |
33dc9b12 | 1218 | free_hash_entry(hash, entry); |
b448c4e3 SR |
1219 | } |
1220 | FTRACE_WARN_ON(hash->count); | |
1221 | } | |
1222 | ||
673feb9d SRV |
1223 | static void free_ftrace_mod(struct ftrace_mod_load *ftrace_mod) |
1224 | { | |
1225 | list_del(&ftrace_mod->list); | |
1226 | kfree(ftrace_mod->module); | |
1227 | kfree(ftrace_mod->func); | |
1228 | kfree(ftrace_mod); | |
1229 | } | |
1230 | ||
1231 | static void clear_ftrace_mod_list(struct list_head *head) | |
1232 | { | |
1233 | struct ftrace_mod_load *p, *n; | |
1234 | ||
1235 | /* stack tracer isn't supported yet */ | |
1236 | if (!head) | |
1237 | return; | |
1238 | ||
1239 | mutex_lock(&ftrace_lock); | |
1240 | list_for_each_entry_safe(p, n, head, list) | |
1241 | free_ftrace_mod(p); | |
1242 | mutex_unlock(&ftrace_lock); | |
1243 | } | |
1244 | ||
33dc9b12 SR |
1245 | static void free_ftrace_hash(struct ftrace_hash *hash) |
1246 | { | |
1247 | if (!hash || hash == EMPTY_HASH) | |
1248 | return; | |
1249 | ftrace_hash_clear(hash); | |
1250 | kfree(hash->buckets); | |
1251 | kfree(hash); | |
1252 | } | |
1253 | ||
07fd5515 SR |
1254 | static void __free_ftrace_hash_rcu(struct rcu_head *rcu) |
1255 | { | |
1256 | struct ftrace_hash *hash; | |
1257 | ||
1258 | hash = container_of(rcu, struct ftrace_hash, rcu); | |
1259 | free_ftrace_hash(hash); | |
1260 | } | |
1261 | ||
1262 | static void free_ftrace_hash_rcu(struct ftrace_hash *hash) | |
1263 | { | |
1264 | if (!hash || hash == EMPTY_HASH) | |
1265 | return; | |
74401729 | 1266 | call_rcu(&hash->rcu, __free_ftrace_hash_rcu); |
07fd5515 SR |
1267 | } |
1268 | ||
5500fa51 JO |
1269 | void ftrace_free_filter(struct ftrace_ops *ops) |
1270 | { | |
f04f24fb | 1271 | ftrace_ops_init(ops); |
33b7f99c SRRH |
1272 | free_ftrace_hash(ops->func_hash->filter_hash); |
1273 | free_ftrace_hash(ops->func_hash->notrace_hash); | |
5500fa51 JO |
1274 | } |
1275 | ||
33dc9b12 SR |
1276 | static struct ftrace_hash *alloc_ftrace_hash(int size_bits) |
1277 | { | |
1278 | struct ftrace_hash *hash; | |
1279 | int size; | |
1280 | ||
1281 | hash = kzalloc(sizeof(*hash), GFP_KERNEL); | |
1282 | if (!hash) | |
1283 | return NULL; | |
1284 | ||
1285 | size = 1 << size_bits; | |
47b0edcb | 1286 | hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL); |
33dc9b12 SR |
1287 | |
1288 | if (!hash->buckets) { | |
1289 | kfree(hash); | |
1290 | return NULL; | |
1291 | } | |
1292 | ||
1293 | hash->size_bits = size_bits; | |
1294 | ||
1295 | return hash; | |
1296 | } | |
1297 | ||
673feb9d SRV |
1298 | |
1299 | static int ftrace_add_mod(struct trace_array *tr, | |
1300 | const char *func, const char *module, | |
1301 | int enable) | |
1302 | { | |
1303 | struct ftrace_mod_load *ftrace_mod; | |
1304 | struct list_head *mod_head = enable ? &tr->mod_trace : &tr->mod_notrace; | |
1305 | ||
1306 | ftrace_mod = kzalloc(sizeof(*ftrace_mod), GFP_KERNEL); | |
1307 | if (!ftrace_mod) | |
1308 | return -ENOMEM; | |
1309 | ||
1310 | ftrace_mod->func = kstrdup(func, GFP_KERNEL); | |
1311 | ftrace_mod->module = kstrdup(module, GFP_KERNEL); | |
1312 | ftrace_mod->enable = enable; | |
1313 | ||
1314 | if (!ftrace_mod->func || !ftrace_mod->module) | |
1315 | goto out_free; | |
1316 | ||
1317 | list_add(&ftrace_mod->list, mod_head); | |
1318 | ||
1319 | return 0; | |
1320 | ||
1321 | out_free: | |
1322 | free_ftrace_mod(ftrace_mod); | |
1323 | ||
1324 | return -ENOMEM; | |
1325 | } | |
1326 | ||
33dc9b12 SR |
1327 | static struct ftrace_hash * |
1328 | alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) | |
1329 | { | |
1330 | struct ftrace_func_entry *entry; | |
1331 | struct ftrace_hash *new_hash; | |
33dc9b12 SR |
1332 | int size; |
1333 | int ret; | |
1334 | int i; | |
1335 | ||
1336 | new_hash = alloc_ftrace_hash(size_bits); | |
1337 | if (!new_hash) | |
1338 | return NULL; | |
1339 | ||
8c08f0d5 SRV |
1340 | if (hash) |
1341 | new_hash->flags = hash->flags; | |
1342 | ||
33dc9b12 | 1343 | /* Empty hash? */ |
06a51d93 | 1344 | if (ftrace_hash_empty(hash)) |
33dc9b12 SR |
1345 | return new_hash; |
1346 | ||
1347 | size = 1 << hash->size_bits; | |
1348 | for (i = 0; i < size; i++) { | |
b67bfe0d | 1349 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { |
33dc9b12 SR |
1350 | ret = add_hash_entry(new_hash, entry->ip); |
1351 | if (ret < 0) | |
1352 | goto free_hash; | |
1353 | } | |
1354 | } | |
1355 | ||
1356 | FTRACE_WARN_ON(new_hash->count != hash->count); | |
1357 | ||
1358 | return new_hash; | |
1359 | ||
1360 | free_hash: | |
1361 | free_ftrace_hash(new_hash); | |
1362 | return NULL; | |
1363 | } | |
1364 | ||
41fb61c2 | 1365 | static void |
84261912 | 1366 | ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, int filter_hash); |
41fb61c2 | 1367 | static void |
84261912 | 1368 | ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, int filter_hash); |
41fb61c2 | 1369 | |
f8b8be8a MH |
1370 | static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops, |
1371 | struct ftrace_hash *new_hash); | |
1372 | ||
3e278c0d NK |
1373 | static struct ftrace_hash * |
1374 | __ftrace_hash_move(struct ftrace_hash *src) | |
33dc9b12 SR |
1375 | { |
1376 | struct ftrace_func_entry *entry; | |
b67bfe0d | 1377 | struct hlist_node *tn; |
33dc9b12 | 1378 | struct hlist_head *hhd; |
07fd5515 | 1379 | struct ftrace_hash *new_hash; |
33dc9b12 SR |
1380 | int size = src->count; |
1381 | int bits = 0; | |
1382 | int i; | |
1383 | ||
1384 | /* | |
3e278c0d | 1385 | * If the new source is empty, just return the empty_hash. |
33dc9b12 | 1386 | */ |
8c08f0d5 | 1387 | if (ftrace_hash_empty(src)) |
3e278c0d | 1388 | return EMPTY_HASH; |
33dc9b12 | 1389 | |
33dc9b12 SR |
1390 | /* |
1391 | * Make the hash size about 1/2 the # found | |
1392 | */ | |
1393 | for (size /= 2; size; size >>= 1) | |
1394 | bits++; | |
1395 | ||
1396 | /* Don't allocate too much */ | |
1397 | if (bits > FTRACE_HASH_MAX_BITS) | |
1398 | bits = FTRACE_HASH_MAX_BITS; | |
1399 | ||
07fd5515 SR |
1400 | new_hash = alloc_ftrace_hash(bits); |
1401 | if (!new_hash) | |
3e278c0d | 1402 | return NULL; |
33dc9b12 | 1403 | |
8c08f0d5 SRV |
1404 | new_hash->flags = src->flags; |
1405 | ||
33dc9b12 SR |
1406 | size = 1 << src->size_bits; |
1407 | for (i = 0; i < size; i++) { | |
1408 | hhd = &src->buckets[i]; | |
b67bfe0d | 1409 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) { |
33dc9b12 | 1410 | remove_hash_entry(src, entry); |
07fd5515 | 1411 | __add_hash_entry(new_hash, entry); |
33dc9b12 SR |
1412 | } |
1413 | } | |
1414 | ||
3e278c0d NK |
1415 | return new_hash; |
1416 | } | |
1417 | ||
1418 | static int | |
1419 | ftrace_hash_move(struct ftrace_ops *ops, int enable, | |
1420 | struct ftrace_hash **dst, struct ftrace_hash *src) | |
1421 | { | |
1422 | struct ftrace_hash *new_hash; | |
1423 | int ret; | |
1424 | ||
1425 | /* Reject setting notrace hash on IPMODIFY ftrace_ops */ | |
1426 | if (ops->flags & FTRACE_OPS_FL_IPMODIFY && !enable) | |
1427 | return -EINVAL; | |
1428 | ||
1429 | new_hash = __ftrace_hash_move(src); | |
1430 | if (!new_hash) | |
1431 | return -ENOMEM; | |
1432 | ||
f8b8be8a MH |
1433 | /* Make sure this can be applied if it is IPMODIFY ftrace_ops */ |
1434 | if (enable) { | |
1435 | /* IPMODIFY should be updated only when filter_hash updating */ | |
1436 | ret = ftrace_hash_ipmodify_update(ops, new_hash); | |
1437 | if (ret < 0) { | |
1438 | free_ftrace_hash(new_hash); | |
1439 | return ret; | |
1440 | } | |
1441 | } | |
1442 | ||
5c27c775 MH |
1443 | /* |
1444 | * Remove the current set, update the hash and add | |
1445 | * them back. | |
1446 | */ | |
84261912 | 1447 | ftrace_hash_rec_disable_modify(ops, enable); |
5c27c775 | 1448 | |
07fd5515 | 1449 | rcu_assign_pointer(*dst, new_hash); |
07fd5515 | 1450 | |
84261912 | 1451 | ftrace_hash_rec_enable_modify(ops, enable); |
41fb61c2 | 1452 | |
5c27c775 | 1453 | return 0; |
33dc9b12 SR |
1454 | } |
1455 | ||
fef5aeee SRRH |
1456 | static bool hash_contains_ip(unsigned long ip, |
1457 | struct ftrace_ops_hash *hash) | |
1458 | { | |
1459 | /* | |
1460 | * The function record is a match if it exists in the filter | |
1461 | * hash and not in the notrace hash. Note, an emty hash is | |
1462 | * considered a match for the filter hash, but an empty | |
1463 | * notrace hash is considered not in the notrace hash. | |
1464 | */ | |
1465 | return (ftrace_hash_empty(hash->filter_hash) || | |
2b2c279c | 1466 | __ftrace_lookup_ip(hash->filter_hash, ip)) && |
fef5aeee | 1467 | (ftrace_hash_empty(hash->notrace_hash) || |
2b2c279c | 1468 | !__ftrace_lookup_ip(hash->notrace_hash, ip)); |
fef5aeee SRRH |
1469 | } |
1470 | ||
b848914c SR |
1471 | /* |
1472 | * Test the hashes for this ops to see if we want to call | |
1473 | * the ops->func or not. | |
1474 | * | |
1475 | * It's a match if the ip is in the ops->filter_hash or | |
1476 | * the filter_hash does not exist or is empty, | |
1477 | * AND | |
1478 | * the ip is not in the ops->notrace_hash. | |
cdbe61bf SR |
1479 | * |
1480 | * This needs to be called with preemption disabled as | |
74401729 | 1481 | * the hashes are freed with call_rcu(). |
b848914c | 1482 | */ |
3306fc4a | 1483 | int |
195a8afc | 1484 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs) |
b848914c | 1485 | { |
fef5aeee | 1486 | struct ftrace_ops_hash hash; |
b848914c SR |
1487 | int ret; |
1488 | ||
195a8afc SRRH |
1489 | #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
1490 | /* | |
1491 | * There's a small race when adding ops that the ftrace handler | |
1492 | * that wants regs, may be called without them. We can not | |
1493 | * allow that handler to be called if regs is NULL. | |
1494 | */ | |
1495 | if (regs == NULL && (ops->flags & FTRACE_OPS_FL_SAVE_REGS)) | |
1496 | return 0; | |
1497 | #endif | |
1498 | ||
f86f4180 CZ |
1499 | rcu_assign_pointer(hash.filter_hash, ops->func_hash->filter_hash); |
1500 | rcu_assign_pointer(hash.notrace_hash, ops->func_hash->notrace_hash); | |
b848914c | 1501 | |
fef5aeee | 1502 | if (hash_contains_ip(ip, &hash)) |
b848914c SR |
1503 | ret = 1; |
1504 | else | |
1505 | ret = 0; | |
b848914c SR |
1506 | |
1507 | return ret; | |
1508 | } | |
1509 | ||
493762fc SR |
1510 | /* |
1511 | * This is a double for. Do not use 'break' to break out of the loop, | |
1512 | * you must use a goto. | |
1513 | */ | |
1514 | #define do_for_each_ftrace_rec(pg, rec) \ | |
1515 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
1516 | int _____i; \ | |
1517 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
1518 | rec = &pg->records[_____i]; | |
1519 | ||
1520 | #define while_for_each_ftrace_rec() \ | |
1521 | } \ | |
1522 | } | |
1523 | ||
5855fead SR |
1524 | |
1525 | static int ftrace_cmp_recs(const void *a, const void *b) | |
1526 | { | |
a650e02a SR |
1527 | const struct dyn_ftrace *key = a; |
1528 | const struct dyn_ftrace *rec = b; | |
5855fead | 1529 | |
a650e02a | 1530 | if (key->flags < rec->ip) |
5855fead | 1531 | return -1; |
a650e02a SR |
1532 | if (key->ip >= rec->ip + MCOUNT_INSN_SIZE) |
1533 | return 1; | |
5855fead SR |
1534 | return 0; |
1535 | } | |
1536 | ||
04cf31a7 ME |
1537 | /** |
1538 | * ftrace_location_range - return the first address of a traced location | |
1539 | * if it touches the given ip range | |
1540 | * @start: start of range to search. | |
1541 | * @end: end of range to search (inclusive). @end points to the last byte | |
1542 | * to check. | |
1543 | * | |
1544 | * Returns rec->ip if the related ftrace location is a least partly within | |
1545 | * the given address range. That is, the first address of the instruction | |
1546 | * that is either a NOP or call to the function tracer. It checks the ftrace | |
1547 | * internal tables to determine if the address belongs or not. | |
1548 | */ | |
1549 | unsigned long ftrace_location_range(unsigned long start, unsigned long end) | |
c88fd863 SR |
1550 | { |
1551 | struct ftrace_page *pg; | |
1552 | struct dyn_ftrace *rec; | |
5855fead | 1553 | struct dyn_ftrace key; |
c88fd863 | 1554 | |
a650e02a SR |
1555 | key.ip = start; |
1556 | key.flags = end; /* overload flags, as it is unsigned long */ | |
5855fead SR |
1557 | |
1558 | for (pg = ftrace_pages_start; pg; pg = pg->next) { | |
a650e02a SR |
1559 | if (end < pg->records[0].ip || |
1560 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) | |
9644302e | 1561 | continue; |
5855fead SR |
1562 | rec = bsearch(&key, pg->records, pg->index, |
1563 | sizeof(struct dyn_ftrace), | |
1564 | ftrace_cmp_recs); | |
1565 | if (rec) | |
f0cf973a | 1566 | return rec->ip; |
5855fead | 1567 | } |
c88fd863 SR |
1568 | |
1569 | return 0; | |
1570 | } | |
1571 | ||
a650e02a SR |
1572 | /** |
1573 | * ftrace_location - return true if the ip giving is a traced location | |
1574 | * @ip: the instruction pointer to check | |
1575 | * | |
f0cf973a | 1576 | * Returns rec->ip if @ip given is a pointer to a ftrace location. |
a650e02a SR |
1577 | * That is, the instruction that is either a NOP or call to |
1578 | * the function tracer. It checks the ftrace internal tables to | |
1579 | * determine if the address belongs or not. | |
1580 | */ | |
f0cf973a | 1581 | unsigned long ftrace_location(unsigned long ip) |
a650e02a SR |
1582 | { |
1583 | return ftrace_location_range(ip, ip); | |
1584 | } | |
1585 | ||
1586 | /** | |
1587 | * ftrace_text_reserved - return true if range contains an ftrace location | |
1588 | * @start: start of range to search | |
1589 | * @end: end of range to search (inclusive). @end points to the last byte to check. | |
1590 | * | |
1591 | * Returns 1 if @start and @end contains a ftrace location. | |
1592 | * That is, the instruction that is either a NOP or call to | |
1593 | * the function tracer. It checks the ftrace internal tables to | |
1594 | * determine if the address belongs or not. | |
1595 | */ | |
d88471cb | 1596 | int ftrace_text_reserved(const void *start, const void *end) |
a650e02a | 1597 | { |
f0cf973a SR |
1598 | unsigned long ret; |
1599 | ||
1600 | ret = ftrace_location_range((unsigned long)start, | |
1601 | (unsigned long)end); | |
1602 | ||
1603 | return (int)!!ret; | |
a650e02a SR |
1604 | } |
1605 | ||
4fbb48cb SRRH |
1606 | /* Test if ops registered to this rec needs regs */ |
1607 | static bool test_rec_ops_needs_regs(struct dyn_ftrace *rec) | |
1608 | { | |
1609 | struct ftrace_ops *ops; | |
1610 | bool keep_regs = false; | |
1611 | ||
1612 | for (ops = ftrace_ops_list; | |
1613 | ops != &ftrace_list_end; ops = ops->next) { | |
1614 | /* pass rec in as regs to have non-NULL val */ | |
1615 | if (ftrace_ops_test(ops, rec->ip, rec)) { | |
1616 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) { | |
1617 | keep_regs = true; | |
1618 | break; | |
1619 | } | |
1620 | } | |
1621 | } | |
1622 | ||
1623 | return keep_regs; | |
1624 | } | |
1625 | ||
a124692b CJ |
1626 | static struct ftrace_ops * |
1627 | ftrace_find_tramp_ops_any(struct dyn_ftrace *rec); | |
1628 | static struct ftrace_ops * | |
1629 | ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, struct ftrace_ops *ops); | |
1630 | ||
84b6d3e6 | 1631 | static bool __ftrace_hash_rec_update(struct ftrace_ops *ops, |
ed926f9b SR |
1632 | int filter_hash, |
1633 | bool inc) | |
1634 | { | |
1635 | struct ftrace_hash *hash; | |
1636 | struct ftrace_hash *other_hash; | |
1637 | struct ftrace_page *pg; | |
1638 | struct dyn_ftrace *rec; | |
84b6d3e6 | 1639 | bool update = false; |
ed926f9b | 1640 | int count = 0; |
8c08f0d5 | 1641 | int all = false; |
ed926f9b SR |
1642 | |
1643 | /* Only update if the ops has been registered */ | |
1644 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
84b6d3e6 | 1645 | return false; |
ed926f9b SR |
1646 | |
1647 | /* | |
1648 | * In the filter_hash case: | |
1649 | * If the count is zero, we update all records. | |
1650 | * Otherwise we just update the items in the hash. | |
1651 | * | |
1652 | * In the notrace_hash case: | |
1653 | * We enable the update in the hash. | |
1654 | * As disabling notrace means enabling the tracing, | |
1655 | * and enabling notrace means disabling, the inc variable | |
1656 | * gets inversed. | |
1657 | */ | |
1658 | if (filter_hash) { | |
33b7f99c SRRH |
1659 | hash = ops->func_hash->filter_hash; |
1660 | other_hash = ops->func_hash->notrace_hash; | |
06a51d93 | 1661 | if (ftrace_hash_empty(hash)) |
8c08f0d5 | 1662 | all = true; |
ed926f9b SR |
1663 | } else { |
1664 | inc = !inc; | |
33b7f99c SRRH |
1665 | hash = ops->func_hash->notrace_hash; |
1666 | other_hash = ops->func_hash->filter_hash; | |
ed926f9b SR |
1667 | /* |
1668 | * If the notrace hash has no items, | |
1669 | * then there's nothing to do. | |
1670 | */ | |
06a51d93 | 1671 | if (ftrace_hash_empty(hash)) |
84b6d3e6 | 1672 | return false; |
ed926f9b SR |
1673 | } |
1674 | ||
1675 | do_for_each_ftrace_rec(pg, rec) { | |
1676 | int in_other_hash = 0; | |
1677 | int in_hash = 0; | |
1678 | int match = 0; | |
1679 | ||
b7ffffbb SRRH |
1680 | if (rec->flags & FTRACE_FL_DISABLED) |
1681 | continue; | |
1682 | ||
ed926f9b SR |
1683 | if (all) { |
1684 | /* | |
1685 | * Only the filter_hash affects all records. | |
1686 | * Update if the record is not in the notrace hash. | |
1687 | */ | |
b848914c | 1688 | if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip)) |
ed926f9b SR |
1689 | match = 1; |
1690 | } else { | |
06a51d93 SR |
1691 | in_hash = !!ftrace_lookup_ip(hash, rec->ip); |
1692 | in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip); | |
ed926f9b SR |
1693 | |
1694 | /* | |
19eab4a4 SRRH |
1695 | * If filter_hash is set, we want to match all functions |
1696 | * that are in the hash but not in the other hash. | |
ed926f9b | 1697 | * |
19eab4a4 SRRH |
1698 | * If filter_hash is not set, then we are decrementing. |
1699 | * That means we match anything that is in the hash | |
1700 | * and also in the other_hash. That is, we need to turn | |
1701 | * off functions in the other hash because they are disabled | |
1702 | * by this hash. | |
ed926f9b SR |
1703 | */ |
1704 | if (filter_hash && in_hash && !in_other_hash) | |
1705 | match = 1; | |
1706 | else if (!filter_hash && in_hash && | |
06a51d93 | 1707 | (in_other_hash || ftrace_hash_empty(other_hash))) |
ed926f9b SR |
1708 | match = 1; |
1709 | } | |
1710 | if (!match) | |
1711 | continue; | |
1712 | ||
1713 | if (inc) { | |
1714 | rec->flags++; | |
0376bde1 | 1715 | if (FTRACE_WARN_ON(ftrace_rec_count(rec) == FTRACE_REF_MAX)) |
84b6d3e6 | 1716 | return false; |
79922b80 SRRH |
1717 | |
1718 | /* | |
1719 | * If there's only a single callback registered to a | |
1720 | * function, and the ops has a trampoline registered | |
1721 | * for it, then we can call it directly. | |
1722 | */ | |
fef5aeee | 1723 | if (ftrace_rec_count(rec) == 1 && ops->trampoline) |
79922b80 | 1724 | rec->flags |= FTRACE_FL_TRAMP; |
fef5aeee | 1725 | else |
79922b80 SRRH |
1726 | /* |
1727 | * If we are adding another function callback | |
1728 | * to this function, and the previous had a | |
bce0b6c5 SRRH |
1729 | * custom trampoline in use, then we need to go |
1730 | * back to the default trampoline. | |
79922b80 | 1731 | */ |
fef5aeee | 1732 | rec->flags &= ~FTRACE_FL_TRAMP; |
79922b80 | 1733 | |
08f6fba5 SR |
1734 | /* |
1735 | * If any ops wants regs saved for this function | |
1736 | * then all ops will get saved regs. | |
1737 | */ | |
1738 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) | |
1739 | rec->flags |= FTRACE_FL_REGS; | |
ed926f9b | 1740 | } else { |
0376bde1 | 1741 | if (FTRACE_WARN_ON(ftrace_rec_count(rec) == 0)) |
84b6d3e6 | 1742 | return false; |
ed926f9b | 1743 | rec->flags--; |
79922b80 | 1744 | |
4fbb48cb SRRH |
1745 | /* |
1746 | * If the rec had REGS enabled and the ops that is | |
1747 | * being removed had REGS set, then see if there is | |
1748 | * still any ops for this record that wants regs. | |
1749 | * If not, we can stop recording them. | |
1750 | */ | |
0376bde1 | 1751 | if (ftrace_rec_count(rec) > 0 && |
4fbb48cb SRRH |
1752 | rec->flags & FTRACE_FL_REGS && |
1753 | ops->flags & FTRACE_OPS_FL_SAVE_REGS) { | |
1754 | if (!test_rec_ops_needs_regs(rec)) | |
1755 | rec->flags &= ~FTRACE_FL_REGS; | |
1756 | } | |
79922b80 | 1757 | |
fef5aeee | 1758 | /* |
a124692b CJ |
1759 | * The TRAMP needs to be set only if rec count |
1760 | * is decremented to one, and the ops that is | |
1761 | * left has a trampoline. As TRAMP can only be | |
1762 | * enabled if there is only a single ops attached | |
1763 | * to it. | |
fef5aeee | 1764 | */ |
a124692b CJ |
1765 | if (ftrace_rec_count(rec) == 1 && |
1766 | ftrace_find_tramp_ops_any(rec)) | |
1767 | rec->flags |= FTRACE_FL_TRAMP; | |
1768 | else | |
1769 | rec->flags &= ~FTRACE_FL_TRAMP; | |
fef5aeee | 1770 | |
79922b80 SRRH |
1771 | /* |
1772 | * flags will be cleared in ftrace_check_record() | |
1773 | * if rec count is zero. | |
1774 | */ | |
ed926f9b SR |
1775 | } |
1776 | count++; | |
84b6d3e6 JO |
1777 | |
1778 | /* Must match FTRACE_UPDATE_CALLS in ftrace_modify_all_code() */ | |
7375dca1 | 1779 | update |= ftrace_test_record(rec, true) != FTRACE_UPDATE_IGNORE; |
84b6d3e6 | 1780 | |
ed926f9b SR |
1781 | /* Shortcut, if we handled all records, we are done. */ |
1782 | if (!all && count == hash->count) | |
84b6d3e6 | 1783 | return update; |
ed926f9b | 1784 | } while_for_each_ftrace_rec(); |
84b6d3e6 JO |
1785 | |
1786 | return update; | |
ed926f9b SR |
1787 | } |
1788 | ||
84b6d3e6 | 1789 | static bool ftrace_hash_rec_disable(struct ftrace_ops *ops, |
ed926f9b SR |
1790 | int filter_hash) |
1791 | { | |
84b6d3e6 | 1792 | return __ftrace_hash_rec_update(ops, filter_hash, 0); |
ed926f9b SR |
1793 | } |
1794 | ||
84b6d3e6 | 1795 | static bool ftrace_hash_rec_enable(struct ftrace_ops *ops, |
ed926f9b SR |
1796 | int filter_hash) |
1797 | { | |
84b6d3e6 | 1798 | return __ftrace_hash_rec_update(ops, filter_hash, 1); |
ed926f9b SR |
1799 | } |
1800 | ||
84261912 SRRH |
1801 | static void ftrace_hash_rec_update_modify(struct ftrace_ops *ops, |
1802 | int filter_hash, int inc) | |
1803 | { | |
1804 | struct ftrace_ops *op; | |
1805 | ||
1806 | __ftrace_hash_rec_update(ops, filter_hash, inc); | |
1807 | ||
1808 | if (ops->func_hash != &global_ops.local_hash) | |
1809 | return; | |
1810 | ||
1811 | /* | |
1812 | * If the ops shares the global_ops hash, then we need to update | |
1813 | * all ops that are enabled and use this hash. | |
1814 | */ | |
1815 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
1816 | /* Already done */ | |
1817 | if (op == ops) | |
1818 | continue; | |
1819 | if (op->func_hash == &global_ops.local_hash) | |
1820 | __ftrace_hash_rec_update(op, filter_hash, inc); | |
1821 | } while_for_each_ftrace_op(op); | |
1822 | } | |
1823 | ||
1824 | static void ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, | |
1825 | int filter_hash) | |
1826 | { | |
1827 | ftrace_hash_rec_update_modify(ops, filter_hash, 0); | |
1828 | } | |
1829 | ||
1830 | static void ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, | |
1831 | int filter_hash) | |
1832 | { | |
1833 | ftrace_hash_rec_update_modify(ops, filter_hash, 1); | |
1834 | } | |
1835 | ||
f8b8be8a MH |
1836 | /* |
1837 | * Try to update IPMODIFY flag on each ftrace_rec. Return 0 if it is OK | |
1838 | * or no-needed to update, -EBUSY if it detects a conflict of the flag | |
1839 | * on a ftrace_rec, and -EINVAL if the new_hash tries to trace all recs. | |
1840 | * Note that old_hash and new_hash has below meanings | |
1841 | * - If the hash is NULL, it hits all recs (if IPMODIFY is set, this is rejected) | |
1842 | * - If the hash is EMPTY_HASH, it hits nothing | |
1843 | * - Anything else hits the recs which match the hash entries. | |
1844 | */ | |
1845 | static int __ftrace_hash_update_ipmodify(struct ftrace_ops *ops, | |
1846 | struct ftrace_hash *old_hash, | |
1847 | struct ftrace_hash *new_hash) | |
1848 | { | |
1849 | struct ftrace_page *pg; | |
1850 | struct dyn_ftrace *rec, *end = NULL; | |
1851 | int in_old, in_new; | |
1852 | ||
1853 | /* Only update if the ops has been registered */ | |
1854 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
1855 | return 0; | |
1856 | ||
1857 | if (!(ops->flags & FTRACE_OPS_FL_IPMODIFY)) | |
1858 | return 0; | |
1859 | ||
1860 | /* | |
1861 | * Since the IPMODIFY is a very address sensitive action, we do not | |
1862 | * allow ftrace_ops to set all functions to new hash. | |
1863 | */ | |
1864 | if (!new_hash || !old_hash) | |
1865 | return -EINVAL; | |
1866 | ||
1867 | /* Update rec->flags */ | |
1868 | do_for_each_ftrace_rec(pg, rec) { | |
546fece4 SRRH |
1869 | |
1870 | if (rec->flags & FTRACE_FL_DISABLED) | |
1871 | continue; | |
1872 | ||
f8b8be8a MH |
1873 | /* We need to update only differences of filter_hash */ |
1874 | in_old = !!ftrace_lookup_ip(old_hash, rec->ip); | |
1875 | in_new = !!ftrace_lookup_ip(new_hash, rec->ip); | |
1876 | if (in_old == in_new) | |
1877 | continue; | |
1878 | ||
1879 | if (in_new) { | |
1880 | /* New entries must ensure no others are using it */ | |
1881 | if (rec->flags & FTRACE_FL_IPMODIFY) | |
1882 | goto rollback; | |
1883 | rec->flags |= FTRACE_FL_IPMODIFY; | |
1884 | } else /* Removed entry */ | |
1885 | rec->flags &= ~FTRACE_FL_IPMODIFY; | |
1886 | } while_for_each_ftrace_rec(); | |
1887 | ||
1888 | return 0; | |
1889 | ||
1890 | rollback: | |
1891 | end = rec; | |
1892 | ||
1893 | /* Roll back what we did above */ | |
1894 | do_for_each_ftrace_rec(pg, rec) { | |
546fece4 SRRH |
1895 | |
1896 | if (rec->flags & FTRACE_FL_DISABLED) | |
1897 | continue; | |
1898 | ||
f8b8be8a MH |
1899 | if (rec == end) |
1900 | goto err_out; | |
1901 | ||
1902 | in_old = !!ftrace_lookup_ip(old_hash, rec->ip); | |
1903 | in_new = !!ftrace_lookup_ip(new_hash, rec->ip); | |
1904 | if (in_old == in_new) | |
1905 | continue; | |
1906 | ||
1907 | if (in_new) | |
1908 | rec->flags &= ~FTRACE_FL_IPMODIFY; | |
1909 | else | |
1910 | rec->flags |= FTRACE_FL_IPMODIFY; | |
1911 | } while_for_each_ftrace_rec(); | |
1912 | ||
1913 | err_out: | |
1914 | return -EBUSY; | |
1915 | } | |
1916 | ||
1917 | static int ftrace_hash_ipmodify_enable(struct ftrace_ops *ops) | |
1918 | { | |
1919 | struct ftrace_hash *hash = ops->func_hash->filter_hash; | |
1920 | ||
1921 | if (ftrace_hash_empty(hash)) | |
1922 | hash = NULL; | |
1923 | ||
1924 | return __ftrace_hash_update_ipmodify(ops, EMPTY_HASH, hash); | |
1925 | } | |
1926 | ||
1927 | /* Disabling always succeeds */ | |
1928 | static void ftrace_hash_ipmodify_disable(struct ftrace_ops *ops) | |
1929 | { | |
1930 | struct ftrace_hash *hash = ops->func_hash->filter_hash; | |
1931 | ||
1932 | if (ftrace_hash_empty(hash)) | |
1933 | hash = NULL; | |
1934 | ||
1935 | __ftrace_hash_update_ipmodify(ops, hash, EMPTY_HASH); | |
1936 | } | |
1937 | ||
1938 | static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops, | |
1939 | struct ftrace_hash *new_hash) | |
1940 | { | |
1941 | struct ftrace_hash *old_hash = ops->func_hash->filter_hash; | |
1942 | ||
1943 | if (ftrace_hash_empty(old_hash)) | |
1944 | old_hash = NULL; | |
1945 | ||
1946 | if (ftrace_hash_empty(new_hash)) | |
1947 | new_hash = NULL; | |
1948 | ||
1949 | return __ftrace_hash_update_ipmodify(ops, old_hash, new_hash); | |
1950 | } | |
1951 | ||
b05086c7 | 1952 | static void print_ip_ins(const char *fmt, const unsigned char *p) |
b17e8a37 SR |
1953 | { |
1954 | int i; | |
1955 | ||
1956 | printk(KERN_CONT "%s", fmt); | |
1957 | ||
1958 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
1959 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
1960 | } | |
1961 | ||
02a392a0 | 1962 | enum ftrace_bug_type ftrace_bug_type; |
b05086c7 | 1963 | const void *ftrace_expected; |
02a392a0 SRRH |
1964 | |
1965 | static void print_bug_type(void) | |
1966 | { | |
1967 | switch (ftrace_bug_type) { | |
1968 | case FTRACE_BUG_UNKNOWN: | |
1969 | break; | |
1970 | case FTRACE_BUG_INIT: | |
1971 | pr_info("Initializing ftrace call sites\n"); | |
1972 | break; | |
1973 | case FTRACE_BUG_NOP: | |
1974 | pr_info("Setting ftrace call site to NOP\n"); | |
1975 | break; | |
1976 | case FTRACE_BUG_CALL: | |
1977 | pr_info("Setting ftrace call site to call ftrace function\n"); | |
1978 | break; | |
1979 | case FTRACE_BUG_UPDATE: | |
1980 | pr_info("Updating ftrace call site to call a different ftrace function\n"); | |
1981 | break; | |
1982 | } | |
1983 | } | |
1984 | ||
c88fd863 SR |
1985 | /** |
1986 | * ftrace_bug - report and shutdown function tracer | |
1987 | * @failed: The failed type (EFAULT, EINVAL, EPERM) | |
4fd3279b | 1988 | * @rec: The record that failed |
c88fd863 SR |
1989 | * |
1990 | * The arch code that enables or disables the function tracing | |
1991 | * can call ftrace_bug() when it has detected a problem in | |
1992 | * modifying the code. @failed should be one of either: | |
1993 | * EFAULT - if the problem happens on reading the @ip address | |
1994 | * EINVAL - if what is read at @ip is not what was expected | |
9efb85c5 | 1995 | * EPERM - if the problem happens on writing to the @ip address |
c88fd863 | 1996 | */ |
4fd3279b | 1997 | void ftrace_bug(int failed, struct dyn_ftrace *rec) |
b17e8a37 | 1998 | { |
4fd3279b SRRH |
1999 | unsigned long ip = rec ? rec->ip : 0; |
2000 | ||
b17e8a37 SR |
2001 | switch (failed) { |
2002 | case -EFAULT: | |
2003 | FTRACE_WARN_ON_ONCE(1); | |
2004 | pr_info("ftrace faulted on modifying "); | |
2005 | print_ip_sym(ip); | |
2006 | break; | |
2007 | case -EINVAL: | |
2008 | FTRACE_WARN_ON_ONCE(1); | |
2009 | pr_info("ftrace failed to modify "); | |
2010 | print_ip_sym(ip); | |
b05086c7 | 2011 | print_ip_ins(" actual: ", (unsigned char *)ip); |
4fd3279b | 2012 | pr_cont("\n"); |
b05086c7 SRRH |
2013 | if (ftrace_expected) { |
2014 | print_ip_ins(" expected: ", ftrace_expected); | |
2015 | pr_cont("\n"); | |
2016 | } | |
b17e8a37 SR |
2017 | break; |
2018 | case -EPERM: | |
2019 | FTRACE_WARN_ON_ONCE(1); | |
2020 | pr_info("ftrace faulted on writing "); | |
2021 | print_ip_sym(ip); | |
2022 | break; | |
2023 | default: | |
2024 | FTRACE_WARN_ON_ONCE(1); | |
2025 | pr_info("ftrace faulted on unknown error "); | |
2026 | print_ip_sym(ip); | |
2027 | } | |
02a392a0 | 2028 | print_bug_type(); |
4fd3279b SRRH |
2029 | if (rec) { |
2030 | struct ftrace_ops *ops = NULL; | |
2031 | ||
2032 | pr_info("ftrace record flags: %lx\n", rec->flags); | |
2033 | pr_cont(" (%ld)%s", ftrace_rec_count(rec), | |
2034 | rec->flags & FTRACE_FL_REGS ? " R" : " "); | |
2035 | if (rec->flags & FTRACE_FL_TRAMP_EN) { | |
2036 | ops = ftrace_find_tramp_ops_any(rec); | |
39daa7b9 SRRH |
2037 | if (ops) { |
2038 | do { | |
2039 | pr_cont("\ttramp: %pS (%pS)", | |
2040 | (void *)ops->trampoline, | |
2041 | (void *)ops->func); | |
2042 | ops = ftrace_find_tramp_ops_next(rec, ops); | |
2043 | } while (ops); | |
2044 | } else | |
4fd3279b SRRH |
2045 | pr_cont("\ttramp: ERROR!"); |
2046 | ||
2047 | } | |
2048 | ip = ftrace_get_addr_curr(rec); | |
39daa7b9 | 2049 | pr_cont("\n expected tramp: %lx\n", ip); |
4fd3279b | 2050 | } |
b17e8a37 SR |
2051 | } |
2052 | ||
7375dca1 | 2053 | static int ftrace_check_record(struct dyn_ftrace *rec, bool enable, bool update) |
5072c59f | 2054 | { |
64fbcd16 | 2055 | unsigned long flag = 0UL; |
e7d3737e | 2056 | |
02a392a0 SRRH |
2057 | ftrace_bug_type = FTRACE_BUG_UNKNOWN; |
2058 | ||
b7ffffbb SRRH |
2059 | if (rec->flags & FTRACE_FL_DISABLED) |
2060 | return FTRACE_UPDATE_IGNORE; | |
2061 | ||
982c350b | 2062 | /* |
30fb6aa7 | 2063 | * If we are updating calls: |
982c350b | 2064 | * |
ed926f9b SR |
2065 | * If the record has a ref count, then we need to enable it |
2066 | * because someone is using it. | |
982c350b | 2067 | * |
ed926f9b SR |
2068 | * Otherwise we make sure its disabled. |
2069 | * | |
30fb6aa7 | 2070 | * If we are disabling calls, then disable all records that |
ed926f9b | 2071 | * are enabled. |
982c350b | 2072 | */ |
0376bde1 | 2073 | if (enable && ftrace_rec_count(rec)) |
ed926f9b | 2074 | flag = FTRACE_FL_ENABLED; |
982c350b | 2075 | |
08f6fba5 | 2076 | /* |
79922b80 SRRH |
2077 | * If enabling and the REGS flag does not match the REGS_EN, or |
2078 | * the TRAMP flag doesn't match the TRAMP_EN, then do not ignore | |
2079 | * this record. Set flags to fail the compare against ENABLED. | |
08f6fba5 | 2080 | */ |
79922b80 SRRH |
2081 | if (flag) { |
2082 | if (!(rec->flags & FTRACE_FL_REGS) != | |
2083 | !(rec->flags & FTRACE_FL_REGS_EN)) | |
2084 | flag |= FTRACE_FL_REGS; | |
2085 | ||
2086 | if (!(rec->flags & FTRACE_FL_TRAMP) != | |
2087 | !(rec->flags & FTRACE_FL_TRAMP_EN)) | |
2088 | flag |= FTRACE_FL_TRAMP; | |
2089 | } | |
08f6fba5 | 2090 | |
64fbcd16 XG |
2091 | /* If the state of this record hasn't changed, then do nothing */ |
2092 | if ((rec->flags & FTRACE_FL_ENABLED) == flag) | |
c88fd863 | 2093 | return FTRACE_UPDATE_IGNORE; |
982c350b | 2094 | |
64fbcd16 | 2095 | if (flag) { |
08f6fba5 SR |
2096 | /* Save off if rec is being enabled (for return value) */ |
2097 | flag ^= rec->flags & FTRACE_FL_ENABLED; | |
2098 | ||
2099 | if (update) { | |
c88fd863 | 2100 | rec->flags |= FTRACE_FL_ENABLED; |
08f6fba5 SR |
2101 | if (flag & FTRACE_FL_REGS) { |
2102 | if (rec->flags & FTRACE_FL_REGS) | |
2103 | rec->flags |= FTRACE_FL_REGS_EN; | |
2104 | else | |
2105 | rec->flags &= ~FTRACE_FL_REGS_EN; | |
2106 | } | |
79922b80 SRRH |
2107 | if (flag & FTRACE_FL_TRAMP) { |
2108 | if (rec->flags & FTRACE_FL_TRAMP) | |
2109 | rec->flags |= FTRACE_FL_TRAMP_EN; | |
2110 | else | |
2111 | rec->flags &= ~FTRACE_FL_TRAMP_EN; | |
2112 | } | |
08f6fba5 SR |
2113 | } |
2114 | ||
2115 | /* | |
2116 | * If this record is being updated from a nop, then | |
2117 | * return UPDATE_MAKE_CALL. | |
08f6fba5 SR |
2118 | * Otherwise, |
2119 | * return UPDATE_MODIFY_CALL to tell the caller to convert | |
f1b2f2bd | 2120 | * from the save regs, to a non-save regs function or |
79922b80 | 2121 | * vice versa, or from a trampoline call. |
08f6fba5 | 2122 | */ |
02a392a0 SRRH |
2123 | if (flag & FTRACE_FL_ENABLED) { |
2124 | ftrace_bug_type = FTRACE_BUG_CALL; | |
08f6fba5 | 2125 | return FTRACE_UPDATE_MAKE_CALL; |
02a392a0 | 2126 | } |
f1b2f2bd | 2127 | |
02a392a0 | 2128 | ftrace_bug_type = FTRACE_BUG_UPDATE; |
f1b2f2bd | 2129 | return FTRACE_UPDATE_MODIFY_CALL; |
c88fd863 SR |
2130 | } |
2131 | ||
08f6fba5 SR |
2132 | if (update) { |
2133 | /* If there's no more users, clear all flags */ | |
0376bde1 | 2134 | if (!ftrace_rec_count(rec)) |
08f6fba5 SR |
2135 | rec->flags = 0; |
2136 | else | |
b24d443b SRRH |
2137 | /* |
2138 | * Just disable the record, but keep the ops TRAMP | |
2139 | * and REGS states. The _EN flags must be disabled though. | |
2140 | */ | |
2141 | rec->flags &= ~(FTRACE_FL_ENABLED | FTRACE_FL_TRAMP_EN | | |
2142 | FTRACE_FL_REGS_EN); | |
08f6fba5 | 2143 | } |
c88fd863 | 2144 | |
02a392a0 | 2145 | ftrace_bug_type = FTRACE_BUG_NOP; |
c88fd863 SR |
2146 | return FTRACE_UPDATE_MAKE_NOP; |
2147 | } | |
2148 | ||
2149 | /** | |
2150 | * ftrace_update_record, set a record that now is tracing or not | |
2151 | * @rec: the record to update | |
7375dca1 | 2152 | * @enable: set to true if the record is tracing, false to force disable |
c88fd863 SR |
2153 | * |
2154 | * The records that represent all functions that can be traced need | |
2155 | * to be updated when tracing has been enabled. | |
2156 | */ | |
7375dca1 | 2157 | int ftrace_update_record(struct dyn_ftrace *rec, bool enable) |
c88fd863 | 2158 | { |
7375dca1 | 2159 | return ftrace_check_record(rec, enable, true); |
c88fd863 SR |
2160 | } |
2161 | ||
2162 | /** | |
2163 | * ftrace_test_record, check if the record has been enabled or not | |
2164 | * @rec: the record to test | |
7375dca1 | 2165 | * @enable: set to true to check if enabled, false if it is disabled |
c88fd863 SR |
2166 | * |
2167 | * The arch code may need to test if a record is already set to | |
2168 | * tracing to determine how to modify the function code that it | |
2169 | * represents. | |
2170 | */ | |
7375dca1 | 2171 | int ftrace_test_record(struct dyn_ftrace *rec, bool enable) |
c88fd863 | 2172 | { |
7375dca1 | 2173 | return ftrace_check_record(rec, enable, false); |
c88fd863 SR |
2174 | } |
2175 | ||
5fecaa04 SRRH |
2176 | static struct ftrace_ops * |
2177 | ftrace_find_tramp_ops_any(struct dyn_ftrace *rec) | |
2178 | { | |
2179 | struct ftrace_ops *op; | |
fef5aeee | 2180 | unsigned long ip = rec->ip; |
5fecaa04 SRRH |
2181 | |
2182 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
2183 | ||
2184 | if (!op->trampoline) | |
2185 | continue; | |
2186 | ||
fef5aeee | 2187 | if (hash_contains_ip(ip, op->func_hash)) |
5fecaa04 SRRH |
2188 | return op; |
2189 | } while_for_each_ftrace_op(op); | |
2190 | ||
2191 | return NULL; | |
2192 | } | |
2193 | ||
39daa7b9 SRRH |
2194 | static struct ftrace_ops * |
2195 | ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, | |
2196 | struct ftrace_ops *op) | |
2197 | { | |
2198 | unsigned long ip = rec->ip; | |
2199 | ||
2200 | while_for_each_ftrace_op(op) { | |
2201 | ||
2202 | if (!op->trampoline) | |
2203 | continue; | |
2204 | ||
2205 | if (hash_contains_ip(ip, op->func_hash)) | |
2206 | return op; | |
2207 | } | |
2208 | ||
2209 | return NULL; | |
2210 | } | |
2211 | ||
79922b80 SRRH |
2212 | static struct ftrace_ops * |
2213 | ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec) | |
2214 | { | |
2215 | struct ftrace_ops *op; | |
fef5aeee | 2216 | unsigned long ip = rec->ip; |
79922b80 | 2217 | |
fef5aeee SRRH |
2218 | /* |
2219 | * Need to check removed ops first. | |
2220 | * If they are being removed, and this rec has a tramp, | |
2221 | * and this rec is in the ops list, then it would be the | |
2222 | * one with the tramp. | |
2223 | */ | |
2224 | if (removed_ops) { | |
2225 | if (hash_contains_ip(ip, &removed_ops->old_hash)) | |
79922b80 SRRH |
2226 | return removed_ops; |
2227 | } | |
2228 | ||
fef5aeee SRRH |
2229 | /* |
2230 | * Need to find the current trampoline for a rec. | |
2231 | * Now, a trampoline is only attached to a rec if there | |
2232 | * was a single 'ops' attached to it. But this can be called | |
2233 | * when we are adding another op to the rec or removing the | |
2234 | * current one. Thus, if the op is being added, we can | |
2235 | * ignore it because it hasn't attached itself to the rec | |
4fc40904 SRRH |
2236 | * yet. |
2237 | * | |
2238 | * If an ops is being modified (hooking to different functions) | |
2239 | * then we don't care about the new functions that are being | |
2240 | * added, just the old ones (that are probably being removed). | |
2241 | * | |
2242 | * If we are adding an ops to a function that already is using | |
2243 | * a trampoline, it needs to be removed (trampolines are only | |
2244 | * for single ops connected), then an ops that is not being | |
2245 | * modified also needs to be checked. | |
fef5aeee | 2246 | */ |
79922b80 | 2247 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
fef5aeee SRRH |
2248 | |
2249 | if (!op->trampoline) | |
2250 | continue; | |
2251 | ||
2252 | /* | |
2253 | * If the ops is being added, it hasn't gotten to | |
2254 | * the point to be removed from this tree yet. | |
2255 | */ | |
2256 | if (op->flags & FTRACE_OPS_FL_ADDING) | |
79922b80 SRRH |
2257 | continue; |
2258 | ||
4fc40904 | 2259 | |
fef5aeee | 2260 | /* |
4fc40904 SRRH |
2261 | * If the ops is being modified and is in the old |
2262 | * hash, then it is probably being removed from this | |
2263 | * function. | |
fef5aeee | 2264 | */ |
fef5aeee SRRH |
2265 | if ((op->flags & FTRACE_OPS_FL_MODIFYING) && |
2266 | hash_contains_ip(ip, &op->old_hash)) | |
79922b80 | 2267 | return op; |
4fc40904 SRRH |
2268 | /* |
2269 | * If the ops is not being added or modified, and it's | |
2270 | * in its normal filter hash, then this must be the one | |
2271 | * we want! | |
2272 | */ | |
2273 | if (!(op->flags & FTRACE_OPS_FL_MODIFYING) && | |
2274 | hash_contains_ip(ip, op->func_hash)) | |
2275 | return op; | |
79922b80 SRRH |
2276 | |
2277 | } while_for_each_ftrace_op(op); | |
2278 | ||
2279 | return NULL; | |
2280 | } | |
2281 | ||
2282 | static struct ftrace_ops * | |
2283 | ftrace_find_tramp_ops_new(struct dyn_ftrace *rec) | |
2284 | { | |
2285 | struct ftrace_ops *op; | |
fef5aeee | 2286 | unsigned long ip = rec->ip; |
79922b80 SRRH |
2287 | |
2288 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
2289 | /* pass rec in as regs to have non-NULL val */ | |
fef5aeee | 2290 | if (hash_contains_ip(ip, op->func_hash)) |
79922b80 SRRH |
2291 | return op; |
2292 | } while_for_each_ftrace_op(op); | |
2293 | ||
2294 | return NULL; | |
2295 | } | |
2296 | ||
7413af1f SRRH |
2297 | /** |
2298 | * ftrace_get_addr_new - Get the call address to set to | |
2299 | * @rec: The ftrace record descriptor | |
2300 | * | |
2301 | * If the record has the FTRACE_FL_REGS set, that means that it | |
2302 | * wants to convert to a callback that saves all regs. If FTRACE_FL_REGS | |
2303 | * is not not set, then it wants to convert to the normal callback. | |
2304 | * | |
2305 | * Returns the address of the trampoline to set to | |
2306 | */ | |
2307 | unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec) | |
2308 | { | |
79922b80 SRRH |
2309 | struct ftrace_ops *ops; |
2310 | ||
2311 | /* Trampolines take precedence over regs */ | |
2312 | if (rec->flags & FTRACE_FL_TRAMP) { | |
2313 | ops = ftrace_find_tramp_ops_new(rec); | |
2314 | if (FTRACE_WARN_ON(!ops || !ops->trampoline)) { | |
bce0b6c5 SRRH |
2315 | pr_warn("Bad trampoline accounting at: %p (%pS) (%lx)\n", |
2316 | (void *)rec->ip, (void *)rec->ip, rec->flags); | |
79922b80 SRRH |
2317 | /* Ftrace is shutting down, return anything */ |
2318 | return (unsigned long)FTRACE_ADDR; | |
2319 | } | |
2320 | return ops->trampoline; | |
2321 | } | |
2322 | ||
7413af1f SRRH |
2323 | if (rec->flags & FTRACE_FL_REGS) |
2324 | return (unsigned long)FTRACE_REGS_ADDR; | |
2325 | else | |
2326 | return (unsigned long)FTRACE_ADDR; | |
2327 | } | |
2328 | ||
2329 | /** | |
2330 | * ftrace_get_addr_curr - Get the call address that is already there | |
2331 | * @rec: The ftrace record descriptor | |
2332 | * | |
2333 | * The FTRACE_FL_REGS_EN is set when the record already points to | |
2334 | * a function that saves all the regs. Basically the '_EN' version | |
2335 | * represents the current state of the function. | |
2336 | * | |
2337 | * Returns the address of the trampoline that is currently being called | |
2338 | */ | |
2339 | unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec) | |
2340 | { | |
79922b80 SRRH |
2341 | struct ftrace_ops *ops; |
2342 | ||
2343 | /* Trampolines take precedence over regs */ | |
2344 | if (rec->flags & FTRACE_FL_TRAMP_EN) { | |
2345 | ops = ftrace_find_tramp_ops_curr(rec); | |
2346 | if (FTRACE_WARN_ON(!ops)) { | |
a395d6a7 JP |
2347 | pr_warn("Bad trampoline accounting at: %p (%pS)\n", |
2348 | (void *)rec->ip, (void *)rec->ip); | |
79922b80 SRRH |
2349 | /* Ftrace is shutting down, return anything */ |
2350 | return (unsigned long)FTRACE_ADDR; | |
2351 | } | |
2352 | return ops->trampoline; | |
2353 | } | |
2354 | ||
7413af1f SRRH |
2355 | if (rec->flags & FTRACE_FL_REGS_EN) |
2356 | return (unsigned long)FTRACE_REGS_ADDR; | |
2357 | else | |
2358 | return (unsigned long)FTRACE_ADDR; | |
2359 | } | |
2360 | ||
c88fd863 | 2361 | static int |
7375dca1 | 2362 | __ftrace_replace_code(struct dyn_ftrace *rec, bool enable) |
c88fd863 | 2363 | { |
08f6fba5 | 2364 | unsigned long ftrace_old_addr; |
c88fd863 SR |
2365 | unsigned long ftrace_addr; |
2366 | int ret; | |
2367 | ||
7c0868e0 | 2368 | ftrace_addr = ftrace_get_addr_new(rec); |
c88fd863 | 2369 | |
7c0868e0 SRRH |
2370 | /* This needs to be done before we call ftrace_update_record */ |
2371 | ftrace_old_addr = ftrace_get_addr_curr(rec); | |
2372 | ||
2373 | ret = ftrace_update_record(rec, enable); | |
08f6fba5 | 2374 | |
02a392a0 SRRH |
2375 | ftrace_bug_type = FTRACE_BUG_UNKNOWN; |
2376 | ||
c88fd863 SR |
2377 | switch (ret) { |
2378 | case FTRACE_UPDATE_IGNORE: | |
2379 | return 0; | |
2380 | ||
2381 | case FTRACE_UPDATE_MAKE_CALL: | |
02a392a0 | 2382 | ftrace_bug_type = FTRACE_BUG_CALL; |
64fbcd16 | 2383 | return ftrace_make_call(rec, ftrace_addr); |
c88fd863 SR |
2384 | |
2385 | case FTRACE_UPDATE_MAKE_NOP: | |
02a392a0 | 2386 | ftrace_bug_type = FTRACE_BUG_NOP; |
39b5552c | 2387 | return ftrace_make_nop(NULL, rec, ftrace_old_addr); |
08f6fba5 | 2388 | |
08f6fba5 | 2389 | case FTRACE_UPDATE_MODIFY_CALL: |
02a392a0 | 2390 | ftrace_bug_type = FTRACE_BUG_UPDATE; |
08f6fba5 | 2391 | return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr); |
5072c59f SR |
2392 | } |
2393 | ||
9efb85c5 | 2394 | return -1; /* unknown ftrace bug */ |
5072c59f SR |
2395 | } |
2396 | ||
a0572f68 | 2397 | void __weak ftrace_replace_code(int mod_flags) |
3c1720f0 | 2398 | { |
3c1720f0 SR |
2399 | struct dyn_ftrace *rec; |
2400 | struct ftrace_page *pg; | |
7375dca1 | 2401 | bool enable = mod_flags & FTRACE_MODIFY_ENABLE_FL; |
a0572f68 | 2402 | int schedulable = mod_flags & FTRACE_MODIFY_MAY_SLEEP_FL; |
6a24a244 | 2403 | int failed; |
3c1720f0 | 2404 | |
45a4a237 SR |
2405 | if (unlikely(ftrace_disabled)) |
2406 | return; | |
2407 | ||
265c831c | 2408 | do_for_each_ftrace_rec(pg, rec) { |
546fece4 SRRH |
2409 | |
2410 | if (rec->flags & FTRACE_FL_DISABLED) | |
2411 | continue; | |
2412 | ||
e4f5d544 | 2413 | failed = __ftrace_replace_code(rec, enable); |
fa9d13cf | 2414 | if (failed) { |
4fd3279b | 2415 | ftrace_bug(failed, rec); |
3279ba37 SR |
2416 | /* Stop processing */ |
2417 | return; | |
3c1720f0 | 2418 | } |
a0572f68 SRV |
2419 | if (schedulable) |
2420 | cond_resched(); | |
265c831c | 2421 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
2422 | } |
2423 | ||
c88fd863 SR |
2424 | struct ftrace_rec_iter { |
2425 | struct ftrace_page *pg; | |
2426 | int index; | |
2427 | }; | |
2428 | ||
2429 | /** | |
2430 | * ftrace_rec_iter_start, start up iterating over traced functions | |
2431 | * | |
2432 | * Returns an iterator handle that is used to iterate over all | |
2433 | * the records that represent address locations where functions | |
2434 | * are traced. | |
2435 | * | |
2436 | * May return NULL if no records are available. | |
2437 | */ | |
2438 | struct ftrace_rec_iter *ftrace_rec_iter_start(void) | |
2439 | { | |
2440 | /* | |
2441 | * We only use a single iterator. | |
2442 | * Protected by the ftrace_lock mutex. | |
2443 | */ | |
2444 | static struct ftrace_rec_iter ftrace_rec_iter; | |
2445 | struct ftrace_rec_iter *iter = &ftrace_rec_iter; | |
2446 | ||
2447 | iter->pg = ftrace_pages_start; | |
2448 | iter->index = 0; | |
2449 | ||
2450 | /* Could have empty pages */ | |
2451 | while (iter->pg && !iter->pg->index) | |
2452 | iter->pg = iter->pg->next; | |
2453 | ||
2454 | if (!iter->pg) | |
2455 | return NULL; | |
2456 | ||
2457 | return iter; | |
2458 | } | |
2459 | ||
2460 | /** | |
2461 | * ftrace_rec_iter_next, get the next record to process. | |
2462 | * @iter: The handle to the iterator. | |
2463 | * | |
2464 | * Returns the next iterator after the given iterator @iter. | |
2465 | */ | |
2466 | struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter) | |
2467 | { | |
2468 | iter->index++; | |
2469 | ||
2470 | if (iter->index >= iter->pg->index) { | |
2471 | iter->pg = iter->pg->next; | |
2472 | iter->index = 0; | |
2473 | ||
2474 | /* Could have empty pages */ | |
2475 | while (iter->pg && !iter->pg->index) | |
2476 | iter->pg = iter->pg->next; | |
2477 | } | |
2478 | ||
2479 | if (!iter->pg) | |
2480 | return NULL; | |
2481 | ||
2482 | return iter; | |
2483 | } | |
2484 | ||
2485 | /** | |
2486 | * ftrace_rec_iter_record, get the record at the iterator location | |
2487 | * @iter: The current iterator location | |
2488 | * | |
2489 | * Returns the record that the current @iter is at. | |
2490 | */ | |
2491 | struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter) | |
2492 | { | |
2493 | return &iter->pg->records[iter->index]; | |
2494 | } | |
2495 | ||
492a7ea5 | 2496 | static int |
31e88909 | 2497 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 | 2498 | { |
593eb8a2 | 2499 | int ret; |
3c1720f0 | 2500 | |
45a4a237 SR |
2501 | if (unlikely(ftrace_disabled)) |
2502 | return 0; | |
2503 | ||
25aac9dc | 2504 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
593eb8a2 | 2505 | if (ret) { |
02a392a0 | 2506 | ftrace_bug_type = FTRACE_BUG_INIT; |
4fd3279b | 2507 | ftrace_bug(ret, rec); |
492a7ea5 | 2508 | return 0; |
37ad5084 | 2509 | } |
492a7ea5 | 2510 | return 1; |
3c1720f0 SR |
2511 | } |
2512 | ||
000ab691 SR |
2513 | /* |
2514 | * archs can override this function if they must do something | |
2515 | * before the modifying code is performed. | |
2516 | */ | |
2517 | int __weak ftrace_arch_code_modify_prepare(void) | |
2518 | { | |
2519 | return 0; | |
2520 | } | |
2521 | ||
2522 | /* | |
2523 | * archs can override this function if they must do something | |
2524 | * after the modifying code is performed. | |
2525 | */ | |
2526 | int __weak ftrace_arch_code_modify_post_process(void) | |
2527 | { | |
2528 | return 0; | |
2529 | } | |
2530 | ||
8ed3e2cf | 2531 | void ftrace_modify_all_code(int command) |
3d083395 | 2532 | { |
59338f75 | 2533 | int update = command & FTRACE_UPDATE_TRACE_FUNC; |
a0572f68 | 2534 | int mod_flags = 0; |
cd21067f | 2535 | int err = 0; |
59338f75 | 2536 | |
a0572f68 SRV |
2537 | if (command & FTRACE_MAY_SLEEP) |
2538 | mod_flags = FTRACE_MODIFY_MAY_SLEEP_FL; | |
2539 | ||
59338f75 SRRH |
2540 | /* |
2541 | * If the ftrace_caller calls a ftrace_ops func directly, | |
2542 | * we need to make sure that it only traces functions it | |
2543 | * expects to trace. When doing the switch of functions, | |
2544 | * we need to update to the ftrace_ops_list_func first | |
2545 | * before the transition between old and new calls are set, | |
2546 | * as the ftrace_ops_list_func will check the ops hashes | |
2547 | * to make sure the ops are having the right functions | |
2548 | * traced. | |
2549 | */ | |
cd21067f PM |
2550 | if (update) { |
2551 | err = ftrace_update_ftrace_func(ftrace_ops_list_func); | |
2552 | if (FTRACE_WARN_ON(err)) | |
2553 | return; | |
2554 | } | |
59338f75 | 2555 | |
8ed3e2cf | 2556 | if (command & FTRACE_UPDATE_CALLS) |
a0572f68 | 2557 | ftrace_replace_code(mod_flags | FTRACE_MODIFY_ENABLE_FL); |
8ed3e2cf | 2558 | else if (command & FTRACE_DISABLE_CALLS) |
a0572f68 | 2559 | ftrace_replace_code(mod_flags); |
d61f82d0 | 2560 | |
405e1d83 SRRH |
2561 | if (update && ftrace_trace_function != ftrace_ops_list_func) { |
2562 | function_trace_op = set_function_trace_op; | |
2563 | smp_wmb(); | |
2564 | /* If irqs are disabled, we are in stop machine */ | |
2565 | if (!irqs_disabled()) | |
2566 | smp_call_function(ftrace_sync_ipi, NULL, 1); | |
cd21067f PM |
2567 | err = ftrace_update_ftrace_func(ftrace_trace_function); |
2568 | if (FTRACE_WARN_ON(err)) | |
2569 | return; | |
405e1d83 | 2570 | } |
d61f82d0 | 2571 | |
8ed3e2cf | 2572 | if (command & FTRACE_START_FUNC_RET) |
cd21067f | 2573 | err = ftrace_enable_ftrace_graph_caller(); |
8ed3e2cf | 2574 | else if (command & FTRACE_STOP_FUNC_RET) |
cd21067f PM |
2575 | err = ftrace_disable_ftrace_graph_caller(); |
2576 | FTRACE_WARN_ON(err); | |
8ed3e2cf SR |
2577 | } |
2578 | ||
2579 | static int __ftrace_modify_code(void *data) | |
2580 | { | |
2581 | int *command = data; | |
2582 | ||
2583 | ftrace_modify_all_code(*command); | |
5a45cfe1 | 2584 | |
d61f82d0 | 2585 | return 0; |
3d083395 SR |
2586 | } |
2587 | ||
c88fd863 SR |
2588 | /** |
2589 | * ftrace_run_stop_machine, go back to the stop machine method | |
2590 | * @command: The command to tell ftrace what to do | |
2591 | * | |
2592 | * If an arch needs to fall back to the stop machine method, the | |
2593 | * it can call this function. | |
2594 | */ | |
2595 | void ftrace_run_stop_machine(int command) | |
2596 | { | |
2597 | stop_machine(__ftrace_modify_code, &command, NULL); | |
2598 | } | |
2599 | ||
2600 | /** | |
2601 | * arch_ftrace_update_code, modify the code to trace or not trace | |
2602 | * @command: The command that needs to be done | |
2603 | * | |
2604 | * Archs can override this function if it does not need to | |
2605 | * run stop_machine() to modify code. | |
2606 | */ | |
2607 | void __weak arch_ftrace_update_code(int command) | |
2608 | { | |
2609 | ftrace_run_stop_machine(command); | |
2610 | } | |
2611 | ||
e309b41d | 2612 | static void ftrace_run_update_code(int command) |
3d083395 | 2613 | { |
000ab691 SR |
2614 | int ret; |
2615 | ||
2616 | ret = ftrace_arch_code_modify_prepare(); | |
2617 | FTRACE_WARN_ON(ret); | |
2618 | if (ret) | |
d5b844a2 | 2619 | return; |
000ab691 | 2620 | |
c88fd863 SR |
2621 | /* |
2622 | * By default we use stop_machine() to modify the code. | |
2623 | * But archs can do what ever they want as long as it | |
2624 | * is safe. The stop_machine() is the safest, but also | |
2625 | * produces the most overhead. | |
2626 | */ | |
2627 | arch_ftrace_update_code(command); | |
2628 | ||
000ab691 SR |
2629 | ret = ftrace_arch_code_modify_post_process(); |
2630 | FTRACE_WARN_ON(ret); | |
3d083395 SR |
2631 | } |
2632 | ||
8252ecf3 | 2633 | static void ftrace_run_modify_code(struct ftrace_ops *ops, int command, |
7485058e | 2634 | struct ftrace_ops_hash *old_hash) |
e1effa01 SRRH |
2635 | { |
2636 | ops->flags |= FTRACE_OPS_FL_MODIFYING; | |
7485058e SRRH |
2637 | ops->old_hash.filter_hash = old_hash->filter_hash; |
2638 | ops->old_hash.notrace_hash = old_hash->notrace_hash; | |
e1effa01 | 2639 | ftrace_run_update_code(command); |
8252ecf3 | 2640 | ops->old_hash.filter_hash = NULL; |
7485058e | 2641 | ops->old_hash.notrace_hash = NULL; |
e1effa01 SRRH |
2642 | ops->flags &= ~FTRACE_OPS_FL_MODIFYING; |
2643 | } | |
2644 | ||
d61f82d0 | 2645 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 2646 | static int ftrace_start_up; |
df4fc315 | 2647 | |
12cce594 SRRH |
2648 | void __weak arch_ftrace_trampoline_free(struct ftrace_ops *ops) |
2649 | { | |
2650 | } | |
2651 | ||
df4fc315 SR |
2652 | static void ftrace_startup_enable(int command) |
2653 | { | |
2654 | if (saved_ftrace_func != ftrace_trace_function) { | |
2655 | saved_ftrace_func = ftrace_trace_function; | |
2656 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2657 | } | |
2658 | ||
2659 | if (!command || !ftrace_enabled) | |
2660 | return; | |
2661 | ||
2662 | ftrace_run_update_code(command); | |
2663 | } | |
d61f82d0 | 2664 | |
e1effa01 SRRH |
2665 | static void ftrace_startup_all(int command) |
2666 | { | |
2667 | update_all_ops = true; | |
2668 | ftrace_startup_enable(command); | |
2669 | update_all_ops = false; | |
2670 | } | |
2671 | ||
3306fc4a | 2672 | int ftrace_startup(struct ftrace_ops *ops, int command) |
3d083395 | 2673 | { |
8a56d776 | 2674 | int ret; |
b848914c | 2675 | |
4eebcc81 | 2676 | if (unlikely(ftrace_disabled)) |
a1cd6173 | 2677 | return -ENODEV; |
4eebcc81 | 2678 | |
8a56d776 SRRH |
2679 | ret = __register_ftrace_function(ops); |
2680 | if (ret) | |
2681 | return ret; | |
2682 | ||
60a7ecf4 | 2683 | ftrace_start_up++; |
d61f82d0 | 2684 | |
e1effa01 SRRH |
2685 | /* |
2686 | * Note that ftrace probes uses this to start up | |
2687 | * and modify functions it will probe. But we still | |
2688 | * set the ADDING flag for modification, as probes | |
2689 | * do not have trampolines. If they add them in the | |
2690 | * future, then the probes will need to distinguish | |
2691 | * between adding and updating probes. | |
2692 | */ | |
2693 | ops->flags |= FTRACE_OPS_FL_ENABLED | FTRACE_OPS_FL_ADDING; | |
66209a5b | 2694 | |
f8b8be8a MH |
2695 | ret = ftrace_hash_ipmodify_enable(ops); |
2696 | if (ret < 0) { | |
2697 | /* Rollback registration process */ | |
2698 | __unregister_ftrace_function(ops); | |
2699 | ftrace_start_up--; | |
2700 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; | |
2701 | return ret; | |
2702 | } | |
2703 | ||
7f50d06b JO |
2704 | if (ftrace_hash_rec_enable(ops, 1)) |
2705 | command |= FTRACE_UPDATE_CALLS; | |
ed926f9b | 2706 | |
df4fc315 | 2707 | ftrace_startup_enable(command); |
a1cd6173 | 2708 | |
e1effa01 SRRH |
2709 | ops->flags &= ~FTRACE_OPS_FL_ADDING; |
2710 | ||
a1cd6173 | 2711 | return 0; |
3d083395 SR |
2712 | } |
2713 | ||
3306fc4a | 2714 | int ftrace_shutdown(struct ftrace_ops *ops, int command) |
3d083395 | 2715 | { |
8a56d776 | 2716 | int ret; |
b848914c | 2717 | |
4eebcc81 | 2718 | if (unlikely(ftrace_disabled)) |
8a56d776 SRRH |
2719 | return -ENODEV; |
2720 | ||
2721 | ret = __unregister_ftrace_function(ops); | |
2722 | if (ret) | |
2723 | return ret; | |
4eebcc81 | 2724 | |
60a7ecf4 | 2725 | ftrace_start_up--; |
9ea1a153 FW |
2726 | /* |
2727 | * Just warn in case of unbalance, no need to kill ftrace, it's not | |
2728 | * critical but the ftrace_call callers may be never nopped again after | |
2729 | * further ftrace uses. | |
2730 | */ | |
2731 | WARN_ON_ONCE(ftrace_start_up < 0); | |
2732 | ||
f8b8be8a MH |
2733 | /* Disabling ipmodify never fails */ |
2734 | ftrace_hash_ipmodify_disable(ops); | |
ed926f9b | 2735 | |
7f50d06b JO |
2736 | if (ftrace_hash_rec_disable(ops, 1)) |
2737 | command |= FTRACE_UPDATE_CALLS; | |
b848914c | 2738 | |
7f50d06b | 2739 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; |
3d083395 | 2740 | |
d61f82d0 SR |
2741 | if (saved_ftrace_func != ftrace_trace_function) { |
2742 | saved_ftrace_func = ftrace_trace_function; | |
2743 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2744 | } | |
3d083395 | 2745 | |
a4c35ed2 SRRH |
2746 | if (!command || !ftrace_enabled) { |
2747 | /* | |
edb096e0 SRV |
2748 | * If these are dynamic or per_cpu ops, they still |
2749 | * need their data freed. Since, function tracing is | |
a4c35ed2 SRRH |
2750 | * not currently active, we can just free them |
2751 | * without synchronizing all CPUs. | |
2752 | */ | |
b3a88803 | 2753 | if (ops->flags & FTRACE_OPS_FL_DYNAMIC) |
edb096e0 SRV |
2754 | goto free_ops; |
2755 | ||
8a56d776 | 2756 | return 0; |
a4c35ed2 | 2757 | } |
d61f82d0 | 2758 | |
79922b80 SRRH |
2759 | /* |
2760 | * If the ops uses a trampoline, then it needs to be | |
2761 | * tested first on update. | |
2762 | */ | |
e1effa01 | 2763 | ops->flags |= FTRACE_OPS_FL_REMOVING; |
79922b80 SRRH |
2764 | removed_ops = ops; |
2765 | ||
fef5aeee SRRH |
2766 | /* The trampoline logic checks the old hashes */ |
2767 | ops->old_hash.filter_hash = ops->func_hash->filter_hash; | |
2768 | ops->old_hash.notrace_hash = ops->func_hash->notrace_hash; | |
2769 | ||
d61f82d0 | 2770 | ftrace_run_update_code(command); |
a4c35ed2 | 2771 | |
84bde62c SRRH |
2772 | /* |
2773 | * If there's no more ops registered with ftrace, run a | |
2774 | * sanity check to make sure all rec flags are cleared. | |
2775 | */ | |
f86f4180 CZ |
2776 | if (rcu_dereference_protected(ftrace_ops_list, |
2777 | lockdep_is_held(&ftrace_lock)) == &ftrace_list_end) { | |
84bde62c SRRH |
2778 | struct ftrace_page *pg; |
2779 | struct dyn_ftrace *rec; | |
2780 | ||
2781 | do_for_each_ftrace_rec(pg, rec) { | |
977c1f9c | 2782 | if (FTRACE_WARN_ON_ONCE(rec->flags & ~FTRACE_FL_DISABLED)) |
84bde62c SRRH |
2783 | pr_warn(" %pS flags:%lx\n", |
2784 | (void *)rec->ip, rec->flags); | |
2785 | } while_for_each_ftrace_rec(); | |
2786 | } | |
2787 | ||
fef5aeee SRRH |
2788 | ops->old_hash.filter_hash = NULL; |
2789 | ops->old_hash.notrace_hash = NULL; | |
2790 | ||
2791 | removed_ops = NULL; | |
e1effa01 | 2792 | ops->flags &= ~FTRACE_OPS_FL_REMOVING; |
79922b80 | 2793 | |
a4c35ed2 SRRH |
2794 | /* |
2795 | * Dynamic ops may be freed, we must make sure that all | |
2796 | * callers are done before leaving this function. | |
ba27f2bc | 2797 | * The same goes for freeing the per_cpu data of the per_cpu |
a4c35ed2 | 2798 | * ops. |
a4c35ed2 | 2799 | */ |
b3a88803 | 2800 | if (ops->flags & FTRACE_OPS_FL_DYNAMIC) { |
0598e4f0 SRV |
2801 | /* |
2802 | * We need to do a hard force of sched synchronization. | |
2803 | * This is because we use preempt_disable() to do RCU, but | |
2804 | * the function tracers can be called where RCU is not watching | |
2805 | * (like before user_exit()). We can not rely on the RCU | |
2806 | * infrastructure to do the synchronization, thus we must do it | |
2807 | * ourselves. | |
2808 | */ | |
a4c35ed2 SRRH |
2809 | schedule_on_each_cpu(ftrace_sync); |
2810 | ||
0598e4f0 SRV |
2811 | /* |
2812 | * When the kernel is preeptive, tasks can be preempted | |
2813 | * while on a ftrace trampoline. Just scheduling a task on | |
2814 | * a CPU is not good enough to flush them. Calling | |
2815 | * synchornize_rcu_tasks() will wait for those tasks to | |
2816 | * execute and either schedule voluntarily or enter user space. | |
2817 | */ | |
30c93704 | 2818 | if (IS_ENABLED(CONFIG_PREEMPTION)) |
0598e4f0 SRV |
2819 | synchronize_rcu_tasks(); |
2820 | ||
edb096e0 | 2821 | free_ops: |
12cce594 | 2822 | arch_ftrace_trampoline_free(ops); |
a4c35ed2 SRRH |
2823 | } |
2824 | ||
8a56d776 | 2825 | return 0; |
3d083395 SR |
2826 | } |
2827 | ||
e309b41d | 2828 | static void ftrace_startup_sysctl(void) |
b0fc494f | 2829 | { |
1619dc3f PA |
2830 | int command; |
2831 | ||
4eebcc81 SR |
2832 | if (unlikely(ftrace_disabled)) |
2833 | return; | |
2834 | ||
d61f82d0 SR |
2835 | /* Force update next time */ |
2836 | saved_ftrace_func = NULL; | |
60a7ecf4 | 2837 | /* ftrace_start_up is true if we want ftrace running */ |
1619dc3f PA |
2838 | if (ftrace_start_up) { |
2839 | command = FTRACE_UPDATE_CALLS; | |
2840 | if (ftrace_graph_active) | |
2841 | command |= FTRACE_START_FUNC_RET; | |
524a3868 | 2842 | ftrace_startup_enable(command); |
1619dc3f | 2843 | } |
b0fc494f SR |
2844 | } |
2845 | ||
e309b41d | 2846 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 2847 | { |
1619dc3f PA |
2848 | int command; |
2849 | ||
4eebcc81 SR |
2850 | if (unlikely(ftrace_disabled)) |
2851 | return; | |
2852 | ||
60a7ecf4 | 2853 | /* ftrace_start_up is true if ftrace is running */ |
1619dc3f PA |
2854 | if (ftrace_start_up) { |
2855 | command = FTRACE_DISABLE_CALLS; | |
2856 | if (ftrace_graph_active) | |
2857 | command |= FTRACE_STOP_FUNC_RET; | |
2858 | ftrace_run_update_code(command); | |
2859 | } | |
b0fc494f SR |
2860 | } |
2861 | ||
a5a1d1c2 | 2862 | static u64 ftrace_update_time; |
3d083395 SR |
2863 | unsigned long ftrace_update_tot_cnt; |
2864 | ||
8c4f3c3f | 2865 | static inline int ops_traces_mod(struct ftrace_ops *ops) |
f7bc8b61 | 2866 | { |
8c4f3c3f SRRH |
2867 | /* |
2868 | * Filter_hash being empty will default to trace module. | |
2869 | * But notrace hash requires a test of individual module functions. | |
2870 | */ | |
33b7f99c SRRH |
2871 | return ftrace_hash_empty(ops->func_hash->filter_hash) && |
2872 | ftrace_hash_empty(ops->func_hash->notrace_hash); | |
8c4f3c3f SRRH |
2873 | } |
2874 | ||
2875 | /* | |
2876 | * Check if the current ops references the record. | |
2877 | * | |
2878 | * If the ops traces all functions, then it was already accounted for. | |
2879 | * If the ops does not trace the current record function, skip it. | |
2880 | * If the ops ignores the function via notrace filter, skip it. | |
2881 | */ | |
2882 | static inline bool | |
2883 | ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec) | |
2884 | { | |
2885 | /* If ops isn't enabled, ignore it */ | |
2886 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
44ec3ec0 | 2887 | return false; |
8c4f3c3f | 2888 | |
b7ffffbb | 2889 | /* If ops traces all then it includes this function */ |
8c4f3c3f | 2890 | if (ops_traces_mod(ops)) |
44ec3ec0 | 2891 | return true; |
8c4f3c3f SRRH |
2892 | |
2893 | /* The function must be in the filter */ | |
33b7f99c | 2894 | if (!ftrace_hash_empty(ops->func_hash->filter_hash) && |
2b2c279c | 2895 | !__ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip)) |
44ec3ec0 | 2896 | return false; |
f7bc8b61 | 2897 | |
8c4f3c3f | 2898 | /* If in notrace hash, we ignore it too */ |
33b7f99c | 2899 | if (ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip)) |
44ec3ec0 | 2900 | return false; |
8c4f3c3f | 2901 | |
44ec3ec0 | 2902 | return true; |
8c4f3c3f SRRH |
2903 | } |
2904 | ||
1dc43cf0 | 2905 | static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs) |
3d083395 | 2906 | { |
85ae32ae | 2907 | struct ftrace_page *pg; |
e94142a6 | 2908 | struct dyn_ftrace *p; |
a5a1d1c2 | 2909 | u64 start, stop; |
1dc43cf0 | 2910 | unsigned long update_cnt = 0; |
b7ffffbb | 2911 | unsigned long rec_flags = 0; |
85ae32ae | 2912 | int i; |
f7bc8b61 | 2913 | |
b7ffffbb SRRH |
2914 | start = ftrace_now(raw_smp_processor_id()); |
2915 | ||
f7bc8b61 | 2916 | /* |
b7ffffbb SRRH |
2917 | * When a module is loaded, this function is called to convert |
2918 | * the calls to mcount in its text to nops, and also to create | |
2919 | * an entry in the ftrace data. Now, if ftrace is activated | |
2920 | * after this call, but before the module sets its text to | |
2921 | * read-only, the modification of enabling ftrace can fail if | |
2922 | * the read-only is done while ftrace is converting the calls. | |
2923 | * To prevent this, the module's records are set as disabled | |
2924 | * and will be enabled after the call to set the module's text | |
2925 | * to read-only. | |
f7bc8b61 | 2926 | */ |
b7ffffbb SRRH |
2927 | if (mod) |
2928 | rec_flags |= FTRACE_FL_DISABLED; | |
3d083395 | 2929 | |
1dc43cf0 | 2930 | for (pg = new_pgs; pg; pg = pg->next) { |
3d083395 | 2931 | |
85ae32ae | 2932 | for (i = 0; i < pg->index; i++) { |
8c4f3c3f | 2933 | |
85ae32ae SR |
2934 | /* If something went wrong, bail without enabling anything */ |
2935 | if (unlikely(ftrace_disabled)) | |
2936 | return -1; | |
f22f9a89 | 2937 | |
85ae32ae | 2938 | p = &pg->records[i]; |
b7ffffbb | 2939 | p->flags = rec_flags; |
f22f9a89 | 2940 | |
85ae32ae SR |
2941 | /* |
2942 | * Do the initial record conversion from mcount jump | |
2943 | * to the NOP instructions. | |
2944 | */ | |
cbdaeaf0 VG |
2945 | if (!__is_defined(CC_USING_NOP_MCOUNT) && |
2946 | !ftrace_code_disable(mod, p)) | |
85ae32ae | 2947 | break; |
5cb084bb | 2948 | |
1dc43cf0 | 2949 | update_cnt++; |
5cb084bb | 2950 | } |
3d083395 SR |
2951 | } |
2952 | ||
750ed1a4 | 2953 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 | 2954 | ftrace_update_time = stop - start; |
1dc43cf0 | 2955 | ftrace_update_tot_cnt += update_cnt; |
3d083395 | 2956 | |
16444a8a ACM |
2957 | return 0; |
2958 | } | |
2959 | ||
a7900875 | 2960 | static int ftrace_allocate_records(struct ftrace_page *pg, int count) |
3c1720f0 | 2961 | { |
a7900875 | 2962 | int order; |
3c1720f0 | 2963 | int cnt; |
3c1720f0 | 2964 | |
a7900875 SR |
2965 | if (WARN_ON(!count)) |
2966 | return -EINVAL; | |
2967 | ||
2968 | order = get_count_order(DIV_ROUND_UP(count, ENTRIES_PER_PAGE)); | |
3c1720f0 SR |
2969 | |
2970 | /* | |
a7900875 SR |
2971 | * We want to fill as much as possible. No more than a page |
2972 | * may be empty. | |
3c1720f0 | 2973 | */ |
a7900875 SR |
2974 | while ((PAGE_SIZE << order) / ENTRY_SIZE >= count + ENTRIES_PER_PAGE) |
2975 | order--; | |
3c1720f0 | 2976 | |
a7900875 SR |
2977 | again: |
2978 | pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); | |
3c1720f0 | 2979 | |
a7900875 SR |
2980 | if (!pg->records) { |
2981 | /* if we can't allocate this size, try something smaller */ | |
2982 | if (!order) | |
2983 | return -ENOMEM; | |
2984 | order >>= 1; | |
2985 | goto again; | |
2986 | } | |
3c1720f0 | 2987 | |
a7900875 SR |
2988 | cnt = (PAGE_SIZE << order) / ENTRY_SIZE; |
2989 | pg->size = cnt; | |
3c1720f0 | 2990 | |
a7900875 SR |
2991 | if (cnt > count) |
2992 | cnt = count; | |
2993 | ||
2994 | return cnt; | |
2995 | } | |
2996 | ||
2997 | static struct ftrace_page * | |
2998 | ftrace_allocate_pages(unsigned long num_to_init) | |
2999 | { | |
3000 | struct ftrace_page *start_pg; | |
3001 | struct ftrace_page *pg; | |
3002 | int order; | |
3003 | int cnt; | |
3004 | ||
3005 | if (!num_to_init) | |
9efb85c5 | 3006 | return NULL; |
a7900875 SR |
3007 | |
3008 | start_pg = pg = kzalloc(sizeof(*pg), GFP_KERNEL); | |
3009 | if (!pg) | |
3010 | return NULL; | |
3011 | ||
3012 | /* | |
3013 | * Try to allocate as much as possible in one continues | |
3014 | * location that fills in all of the space. We want to | |
3015 | * waste as little space as possible. | |
3016 | */ | |
3017 | for (;;) { | |
3018 | cnt = ftrace_allocate_records(pg, num_to_init); | |
3019 | if (cnt < 0) | |
3020 | goto free_pages; | |
3021 | ||
3022 | num_to_init -= cnt; | |
3023 | if (!num_to_init) | |
3c1720f0 SR |
3024 | break; |
3025 | ||
a7900875 SR |
3026 | pg->next = kzalloc(sizeof(*pg), GFP_KERNEL); |
3027 | if (!pg->next) | |
3028 | goto free_pages; | |
3029 | ||
3c1720f0 SR |
3030 | pg = pg->next; |
3031 | } | |
3032 | ||
a7900875 SR |
3033 | return start_pg; |
3034 | ||
3035 | free_pages: | |
1f61be00 NK |
3036 | pg = start_pg; |
3037 | while (pg) { | |
a7900875 SR |
3038 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); |
3039 | free_pages((unsigned long)pg->records, order); | |
3040 | start_pg = pg->next; | |
3041 | kfree(pg); | |
3042 | pg = start_pg; | |
3043 | } | |
3044 | pr_info("ftrace: FAILED to allocate memory for functions\n"); | |
3045 | return NULL; | |
3046 | } | |
3047 | ||
5072c59f SR |
3048 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ |
3049 | ||
3050 | struct ftrace_iterator { | |
98c4fd04 | 3051 | loff_t pos; |
4aeb6967 | 3052 | loff_t func_pos; |
5985ea8b | 3053 | loff_t mod_pos; |
4aeb6967 SR |
3054 | struct ftrace_page *pg; |
3055 | struct dyn_ftrace *func; | |
3056 | struct ftrace_func_probe *probe; | |
eee8ded1 | 3057 | struct ftrace_func_entry *probe_entry; |
4aeb6967 | 3058 | struct trace_parser parser; |
1cf41dd7 | 3059 | struct ftrace_hash *hash; |
33dc9b12 | 3060 | struct ftrace_ops *ops; |
5985ea8b SRV |
3061 | struct trace_array *tr; |
3062 | struct list_head *mod_list; | |
eee8ded1 | 3063 | int pidx; |
4aeb6967 SR |
3064 | int idx; |
3065 | unsigned flags; | |
5072c59f SR |
3066 | }; |
3067 | ||
8fc0c701 | 3068 | static void * |
eee8ded1 | 3069 | t_probe_next(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
3070 | { |
3071 | struct ftrace_iterator *iter = m->private; | |
d2afd57a | 3072 | struct trace_array *tr = iter->ops->private; |
04ec7bb6 | 3073 | struct list_head *func_probes; |
eee8ded1 SRV |
3074 | struct ftrace_hash *hash; |
3075 | struct list_head *next; | |
4aeb6967 | 3076 | struct hlist_node *hnd = NULL; |
8fc0c701 | 3077 | struct hlist_head *hhd; |
eee8ded1 | 3078 | int size; |
8fc0c701 | 3079 | |
8fc0c701 | 3080 | (*pos)++; |
98c4fd04 | 3081 | iter->pos = *pos; |
8fc0c701 | 3082 | |
04ec7bb6 | 3083 | if (!tr) |
8fc0c701 SR |
3084 | return NULL; |
3085 | ||
04ec7bb6 SRV |
3086 | func_probes = &tr->func_probes; |
3087 | if (list_empty(func_probes)) | |
8fc0c701 SR |
3088 | return NULL; |
3089 | ||
eee8ded1 | 3090 | if (!iter->probe) { |
04ec7bb6 | 3091 | next = func_probes->next; |
7b60f3d8 | 3092 | iter->probe = list_entry(next, struct ftrace_func_probe, list); |
eee8ded1 SRV |
3093 | } |
3094 | ||
3095 | if (iter->probe_entry) | |
3096 | hnd = &iter->probe_entry->hlist; | |
3097 | ||
3098 | hash = iter->probe->ops.func_hash->filter_hash; | |
7bd46644 | 3099 | |
372e0d01 SRV |
3100 | /* |
3101 | * A probe being registered may temporarily have an empty hash | |
3102 | * and it's at the end of the func_probes list. | |
3103 | */ | |
3104 | if (!hash || hash == EMPTY_HASH) | |
7bd46644 NR |
3105 | return NULL; |
3106 | ||
eee8ded1 SRV |
3107 | size = 1 << hash->size_bits; |
3108 | ||
3109 | retry: | |
3110 | if (iter->pidx >= size) { | |
04ec7bb6 | 3111 | if (iter->probe->list.next == func_probes) |
eee8ded1 SRV |
3112 | return NULL; |
3113 | next = iter->probe->list.next; | |
7b60f3d8 | 3114 | iter->probe = list_entry(next, struct ftrace_func_probe, list); |
eee8ded1 SRV |
3115 | hash = iter->probe->ops.func_hash->filter_hash; |
3116 | size = 1 << hash->size_bits; | |
3117 | iter->pidx = 0; | |
3118 | } | |
3119 | ||
3120 | hhd = &hash->buckets[iter->pidx]; | |
8fc0c701 SR |
3121 | |
3122 | if (hlist_empty(hhd)) { | |
eee8ded1 | 3123 | iter->pidx++; |
8fc0c701 SR |
3124 | hnd = NULL; |
3125 | goto retry; | |
3126 | } | |
3127 | ||
3128 | if (!hnd) | |
3129 | hnd = hhd->first; | |
3130 | else { | |
3131 | hnd = hnd->next; | |
3132 | if (!hnd) { | |
eee8ded1 | 3133 | iter->pidx++; |
8fc0c701 SR |
3134 | goto retry; |
3135 | } | |
3136 | } | |
3137 | ||
4aeb6967 SR |
3138 | if (WARN_ON_ONCE(!hnd)) |
3139 | return NULL; | |
3140 | ||
eee8ded1 | 3141 | iter->probe_entry = hlist_entry(hnd, struct ftrace_func_entry, hlist); |
4aeb6967 SR |
3142 | |
3143 | return iter; | |
8fc0c701 SR |
3144 | } |
3145 | ||
eee8ded1 | 3146 | static void *t_probe_start(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
3147 | { |
3148 | struct ftrace_iterator *iter = m->private; | |
3149 | void *p = NULL; | |
d82d6244 LZ |
3150 | loff_t l; |
3151 | ||
eee8ded1 | 3152 | if (!(iter->flags & FTRACE_ITER_DO_PROBES)) |
69a3083c SR |
3153 | return NULL; |
3154 | ||
5985ea8b | 3155 | if (iter->mod_pos > *pos) |
2bccfffd | 3156 | return NULL; |
8fc0c701 | 3157 | |
eee8ded1 SRV |
3158 | iter->probe = NULL; |
3159 | iter->probe_entry = NULL; | |
3160 | iter->pidx = 0; | |
5985ea8b | 3161 | for (l = 0; l <= (*pos - iter->mod_pos); ) { |
eee8ded1 | 3162 | p = t_probe_next(m, &l); |
d82d6244 LZ |
3163 | if (!p) |
3164 | break; | |
3165 | } | |
4aeb6967 SR |
3166 | if (!p) |
3167 | return NULL; | |
3168 | ||
98c4fd04 | 3169 | /* Only set this if we have an item */ |
eee8ded1 | 3170 | iter->flags |= FTRACE_ITER_PROBE; |
98c4fd04 | 3171 | |
4aeb6967 | 3172 | return iter; |
8fc0c701 SR |
3173 | } |
3174 | ||
4aeb6967 | 3175 | static int |
eee8ded1 | 3176 | t_probe_show(struct seq_file *m, struct ftrace_iterator *iter) |
8fc0c701 | 3177 | { |
eee8ded1 | 3178 | struct ftrace_func_entry *probe_entry; |
7b60f3d8 SRV |
3179 | struct ftrace_probe_ops *probe_ops; |
3180 | struct ftrace_func_probe *probe; | |
8fc0c701 | 3181 | |
eee8ded1 SRV |
3182 | probe = iter->probe; |
3183 | probe_entry = iter->probe_entry; | |
8fc0c701 | 3184 | |
eee8ded1 | 3185 | if (WARN_ON_ONCE(!probe || !probe_entry)) |
4aeb6967 | 3186 | return -EIO; |
8fc0c701 | 3187 | |
7b60f3d8 | 3188 | probe_ops = probe->probe_ops; |
809dcf29 | 3189 | |
7b60f3d8 | 3190 | if (probe_ops->print) |
6e444319 | 3191 | return probe_ops->print(m, probe_entry->ip, probe_ops, probe->data); |
8fc0c701 | 3192 | |
7b60f3d8 SRV |
3193 | seq_printf(m, "%ps:%ps\n", (void *)probe_entry->ip, |
3194 | (void *)probe_ops->func); | |
8fc0c701 SR |
3195 | |
3196 | return 0; | |
3197 | } | |
3198 | ||
5985ea8b SRV |
3199 | static void * |
3200 | t_mod_next(struct seq_file *m, loff_t *pos) | |
3201 | { | |
3202 | struct ftrace_iterator *iter = m->private; | |
3203 | struct trace_array *tr = iter->tr; | |
3204 | ||
3205 | (*pos)++; | |
3206 | iter->pos = *pos; | |
3207 | ||
3208 | iter->mod_list = iter->mod_list->next; | |
3209 | ||
3210 | if (iter->mod_list == &tr->mod_trace || | |
3211 | iter->mod_list == &tr->mod_notrace) { | |
3212 | iter->flags &= ~FTRACE_ITER_MOD; | |
3213 | return NULL; | |
3214 | } | |
3215 | ||
3216 | iter->mod_pos = *pos; | |
3217 | ||
3218 | return iter; | |
3219 | } | |
3220 | ||
3221 | static void *t_mod_start(struct seq_file *m, loff_t *pos) | |
3222 | { | |
3223 | struct ftrace_iterator *iter = m->private; | |
3224 | void *p = NULL; | |
3225 | loff_t l; | |
3226 | ||
3227 | if (iter->func_pos > *pos) | |
3228 | return NULL; | |
3229 | ||
3230 | iter->mod_pos = iter->func_pos; | |
3231 | ||
3232 | /* probes are only available if tr is set */ | |
3233 | if (!iter->tr) | |
3234 | return NULL; | |
3235 | ||
3236 | for (l = 0; l <= (*pos - iter->func_pos); ) { | |
3237 | p = t_mod_next(m, &l); | |
3238 | if (!p) | |
3239 | break; | |
3240 | } | |
3241 | if (!p) { | |
3242 | iter->flags &= ~FTRACE_ITER_MOD; | |
3243 | return t_probe_start(m, pos); | |
3244 | } | |
3245 | ||
3246 | /* Only set this if we have an item */ | |
3247 | iter->flags |= FTRACE_ITER_MOD; | |
3248 | ||
3249 | return iter; | |
3250 | } | |
3251 | ||
3252 | static int | |
3253 | t_mod_show(struct seq_file *m, struct ftrace_iterator *iter) | |
3254 | { | |
3255 | struct ftrace_mod_load *ftrace_mod; | |
3256 | struct trace_array *tr = iter->tr; | |
3257 | ||
3258 | if (WARN_ON_ONCE(!iter->mod_list) || | |
3259 | iter->mod_list == &tr->mod_trace || | |
3260 | iter->mod_list == &tr->mod_notrace) | |
3261 | return -EIO; | |
3262 | ||
3263 | ftrace_mod = list_entry(iter->mod_list, struct ftrace_mod_load, list); | |
3264 | ||
3265 | if (ftrace_mod->func) | |
3266 | seq_printf(m, "%s", ftrace_mod->func); | |
3267 | else | |
3268 | seq_putc(m, '*'); | |
3269 | ||
3270 | seq_printf(m, ":mod:%s\n", ftrace_mod->module); | |
3271 | ||
3272 | return 0; | |
3273 | } | |
3274 | ||
e309b41d | 3275 | static void * |
5bd84629 | 3276 | t_func_next(struct seq_file *m, loff_t *pos) |
5072c59f SR |
3277 | { |
3278 | struct ftrace_iterator *iter = m->private; | |
3279 | struct dyn_ftrace *rec = NULL; | |
3280 | ||
3281 | (*pos)++; | |
0c75a3ed | 3282 | |
5072c59f SR |
3283 | retry: |
3284 | if (iter->idx >= iter->pg->index) { | |
3285 | if (iter->pg->next) { | |
3286 | iter->pg = iter->pg->next; | |
3287 | iter->idx = 0; | |
3288 | goto retry; | |
3289 | } | |
3290 | } else { | |
3291 | rec = &iter->pg->records[iter->idx++]; | |
c20489da SRV |
3292 | if (((iter->flags & (FTRACE_ITER_FILTER | FTRACE_ITER_NOTRACE)) && |
3293 | !ftrace_lookup_ip(iter->hash, rec->ip)) || | |
647bcd03 SR |
3294 | |
3295 | ((iter->flags & FTRACE_ITER_ENABLED) && | |
23ea9c4d | 3296 | !(rec->flags & FTRACE_FL_ENABLED))) { |
647bcd03 | 3297 | |
5072c59f SR |
3298 | rec = NULL; |
3299 | goto retry; | |
3300 | } | |
3301 | } | |
3302 | ||
4aeb6967 | 3303 | if (!rec) |
5bd84629 | 3304 | return NULL; |
4aeb6967 | 3305 | |
5bd84629 | 3306 | iter->pos = iter->func_pos = *pos; |
4aeb6967 SR |
3307 | iter->func = rec; |
3308 | ||
3309 | return iter; | |
5072c59f SR |
3310 | } |
3311 | ||
5bd84629 SRV |
3312 | static void * |
3313 | t_next(struct seq_file *m, void *v, loff_t *pos) | |
3314 | { | |
3315 | struct ftrace_iterator *iter = m->private; | |
5985ea8b | 3316 | loff_t l = *pos; /* t_probe_start() must use original pos */ |
5bd84629 SRV |
3317 | void *ret; |
3318 | ||
3319 | if (unlikely(ftrace_disabled)) | |
3320 | return NULL; | |
3321 | ||
eee8ded1 SRV |
3322 | if (iter->flags & FTRACE_ITER_PROBE) |
3323 | return t_probe_next(m, pos); | |
5bd84629 | 3324 | |
5985ea8b SRV |
3325 | if (iter->flags & FTRACE_ITER_MOD) |
3326 | return t_mod_next(m, pos); | |
3327 | ||
5bd84629 | 3328 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
eee8ded1 | 3329 | /* next must increment pos, and t_probe_start does not */ |
5bd84629 | 3330 | (*pos)++; |
5985ea8b | 3331 | return t_mod_start(m, &l); |
5bd84629 SRV |
3332 | } |
3333 | ||
3334 | ret = t_func_next(m, pos); | |
3335 | ||
3336 | if (!ret) | |
5985ea8b | 3337 | return t_mod_start(m, &l); |
5bd84629 SRV |
3338 | |
3339 | return ret; | |
3340 | } | |
3341 | ||
98c4fd04 SR |
3342 | static void reset_iter_read(struct ftrace_iterator *iter) |
3343 | { | |
3344 | iter->pos = 0; | |
3345 | iter->func_pos = 0; | |
5985ea8b | 3346 | iter->flags &= ~(FTRACE_ITER_PRINTALL | FTRACE_ITER_PROBE | FTRACE_ITER_MOD); |
5072c59f SR |
3347 | } |
3348 | ||
3349 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3350 | { | |
3351 | struct ftrace_iterator *iter = m->private; | |
3352 | void *p = NULL; | |
694ce0a5 | 3353 | loff_t l; |
5072c59f | 3354 | |
8fc0c701 | 3355 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
3356 | |
3357 | if (unlikely(ftrace_disabled)) | |
3358 | return NULL; | |
3359 | ||
98c4fd04 SR |
3360 | /* |
3361 | * If an lseek was done, then reset and start from beginning. | |
3362 | */ | |
3363 | if (*pos < iter->pos) | |
3364 | reset_iter_read(iter); | |
3365 | ||
0c75a3ed SR |
3366 | /* |
3367 | * For set_ftrace_filter reading, if we have the filter | |
3368 | * off, we can short cut and just print out that all | |
3369 | * functions are enabled. | |
3370 | */ | |
c20489da SRV |
3371 | if ((iter->flags & (FTRACE_ITER_FILTER | FTRACE_ITER_NOTRACE)) && |
3372 | ftrace_hash_empty(iter->hash)) { | |
43ff926a | 3373 | iter->func_pos = 1; /* Account for the message */ |
0c75a3ed | 3374 | if (*pos > 0) |
5985ea8b | 3375 | return t_mod_start(m, pos); |
0c75a3ed | 3376 | iter->flags |= FTRACE_ITER_PRINTALL; |
df091625 | 3377 | /* reset in case of seek/pread */ |
eee8ded1 | 3378 | iter->flags &= ~FTRACE_ITER_PROBE; |
0c75a3ed SR |
3379 | return iter; |
3380 | } | |
3381 | ||
5985ea8b SRV |
3382 | if (iter->flags & FTRACE_ITER_MOD) |
3383 | return t_mod_start(m, pos); | |
8fc0c701 | 3384 | |
98c4fd04 SR |
3385 | /* |
3386 | * Unfortunately, we need to restart at ftrace_pages_start | |
3387 | * every time we let go of the ftrace_mutex. This is because | |
3388 | * those pointers can change without the lock. | |
3389 | */ | |
694ce0a5 LZ |
3390 | iter->pg = ftrace_pages_start; |
3391 | iter->idx = 0; | |
3392 | for (l = 0; l <= *pos; ) { | |
5bd84629 | 3393 | p = t_func_next(m, &l); |
694ce0a5 LZ |
3394 | if (!p) |
3395 | break; | |
50cdaf08 | 3396 | } |
5821e1b7 | 3397 | |
69a3083c | 3398 | if (!p) |
5985ea8b | 3399 | return t_mod_start(m, pos); |
4aeb6967 SR |
3400 | |
3401 | return iter; | |
5072c59f SR |
3402 | } |
3403 | ||
3404 | static void t_stop(struct seq_file *m, void *p) | |
3405 | { | |
8fc0c701 | 3406 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
3407 | } |
3408 | ||
15d5b02c SRRH |
3409 | void * __weak |
3410 | arch_ftrace_trampoline_func(struct ftrace_ops *ops, struct dyn_ftrace *rec) | |
3411 | { | |
3412 | return NULL; | |
3413 | } | |
3414 | ||
3415 | static void add_trampoline_func(struct seq_file *m, struct ftrace_ops *ops, | |
3416 | struct dyn_ftrace *rec) | |
3417 | { | |
3418 | void *ptr; | |
3419 | ||
3420 | ptr = arch_ftrace_trampoline_func(ops, rec); | |
3421 | if (ptr) | |
3422 | seq_printf(m, " ->%pS", ptr); | |
3423 | } | |
3424 | ||
5072c59f SR |
3425 | static int t_show(struct seq_file *m, void *v) |
3426 | { | |
0c75a3ed | 3427 | struct ftrace_iterator *iter = m->private; |
4aeb6967 | 3428 | struct dyn_ftrace *rec; |
5072c59f | 3429 | |
eee8ded1 SRV |
3430 | if (iter->flags & FTRACE_ITER_PROBE) |
3431 | return t_probe_show(m, iter); | |
8fc0c701 | 3432 | |
5985ea8b SRV |
3433 | if (iter->flags & FTRACE_ITER_MOD) |
3434 | return t_mod_show(m, iter); | |
3435 | ||
0c75a3ed | 3436 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
8c006cf7 | 3437 | if (iter->flags & FTRACE_ITER_NOTRACE) |
fa6f0cc7 | 3438 | seq_puts(m, "#### no functions disabled ####\n"); |
8c006cf7 | 3439 | else |
fa6f0cc7 | 3440 | seq_puts(m, "#### all functions enabled ####\n"); |
0c75a3ed SR |
3441 | return 0; |
3442 | } | |
3443 | ||
4aeb6967 SR |
3444 | rec = iter->func; |
3445 | ||
5072c59f SR |
3446 | if (!rec) |
3447 | return 0; | |
3448 | ||
647bcd03 | 3449 | seq_printf(m, "%ps", (void *)rec->ip); |
9674b2fa | 3450 | if (iter->flags & FTRACE_ITER_ENABLED) { |
030f4e1c | 3451 | struct ftrace_ops *ops; |
15d5b02c | 3452 | |
f8b8be8a | 3453 | seq_printf(m, " (%ld)%s%s", |
0376bde1 | 3454 | ftrace_rec_count(rec), |
f8b8be8a MH |
3455 | rec->flags & FTRACE_FL_REGS ? " R" : " ", |
3456 | rec->flags & FTRACE_FL_IPMODIFY ? " I" : " "); | |
9674b2fa | 3457 | if (rec->flags & FTRACE_FL_TRAMP_EN) { |
5fecaa04 | 3458 | ops = ftrace_find_tramp_ops_any(rec); |
39daa7b9 SRRH |
3459 | if (ops) { |
3460 | do { | |
3461 | seq_printf(m, "\ttramp: %pS (%pS)", | |
3462 | (void *)ops->trampoline, | |
3463 | (void *)ops->func); | |
030f4e1c | 3464 | add_trampoline_func(m, ops, rec); |
39daa7b9 SRRH |
3465 | ops = ftrace_find_tramp_ops_next(rec, ops); |
3466 | } while (ops); | |
3467 | } else | |
fa6f0cc7 | 3468 | seq_puts(m, "\ttramp: ERROR!"); |
030f4e1c SRRH |
3469 | } else { |
3470 | add_trampoline_func(m, NULL, rec); | |
9674b2fa SRRH |
3471 | } |
3472 | } | |
3473 | ||
fa6f0cc7 | 3474 | seq_putc(m, '\n'); |
5072c59f SR |
3475 | |
3476 | return 0; | |
3477 | } | |
3478 | ||
88e9d34c | 3479 | static const struct seq_operations show_ftrace_seq_ops = { |
5072c59f SR |
3480 | .start = t_start, |
3481 | .next = t_next, | |
3482 | .stop = t_stop, | |
3483 | .show = t_show, | |
3484 | }; | |
3485 | ||
e309b41d | 3486 | static int |
5072c59f SR |
3487 | ftrace_avail_open(struct inode *inode, struct file *file) |
3488 | { | |
3489 | struct ftrace_iterator *iter; | |
17911ff3 SRV |
3490 | int ret; |
3491 | ||
3492 | ret = security_locked_down(LOCKDOWN_TRACEFS); | |
3493 | if (ret) | |
3494 | return ret; | |
5072c59f | 3495 | |
4eebcc81 SR |
3496 | if (unlikely(ftrace_disabled)) |
3497 | return -ENODEV; | |
3498 | ||
50e18b94 | 3499 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
c1bc5919 SRV |
3500 | if (!iter) |
3501 | return -ENOMEM; | |
5072c59f | 3502 | |
c1bc5919 SRV |
3503 | iter->pg = ftrace_pages_start; |
3504 | iter->ops = &global_ops; | |
3505 | ||
3506 | return 0; | |
5072c59f SR |
3507 | } |
3508 | ||
647bcd03 SR |
3509 | static int |
3510 | ftrace_enabled_open(struct inode *inode, struct file *file) | |
3511 | { | |
3512 | struct ftrace_iterator *iter; | |
647bcd03 | 3513 | |
17911ff3 SRV |
3514 | /* |
3515 | * This shows us what functions are currently being | |
3516 | * traced and by what. Not sure if we want lockdown | |
3517 | * to hide such critical information for an admin. | |
3518 | * Although, perhaps it can show information we don't | |
3519 | * want people to see, but if something is tracing | |
3520 | * something, we probably want to know about it. | |
3521 | */ | |
3522 | ||
50e18b94 | 3523 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
c1bc5919 SRV |
3524 | if (!iter) |
3525 | return -ENOMEM; | |
647bcd03 | 3526 | |
c1bc5919 SRV |
3527 | iter->pg = ftrace_pages_start; |
3528 | iter->flags = FTRACE_ITER_ENABLED; | |
3529 | iter->ops = &global_ops; | |
3530 | ||
3531 | return 0; | |
647bcd03 SR |
3532 | } |
3533 | ||
fc13cb0c SR |
3534 | /** |
3535 | * ftrace_regex_open - initialize function tracer filter files | |
3536 | * @ops: The ftrace_ops that hold the hash filters | |
3537 | * @flag: The type of filter to process | |
3538 | * @inode: The inode, usually passed in to your open routine | |
3539 | * @file: The file, usually passed in to your open routine | |
3540 | * | |
3541 | * ftrace_regex_open() initializes the filter files for the | |
3542 | * @ops. Depending on @flag it may process the filter hash or | |
3543 | * the notrace hash of @ops. With this called from the open | |
3544 | * routine, you can use ftrace_filter_write() for the write | |
3545 | * routine if @flag has FTRACE_ITER_FILTER set, or | |
3546 | * ftrace_notrace_write() if @flag has FTRACE_ITER_NOTRACE set. | |
098c879e | 3547 | * tracing_lseek() should be used as the lseek routine, and |
fc13cb0c SR |
3548 | * release must call ftrace_regex_release(). |
3549 | */ | |
3550 | int | |
f45948e8 | 3551 | ftrace_regex_open(struct ftrace_ops *ops, int flag, |
1cf41dd7 | 3552 | struct inode *inode, struct file *file) |
5072c59f SR |
3553 | { |
3554 | struct ftrace_iterator *iter; | |
f45948e8 | 3555 | struct ftrace_hash *hash; |
673feb9d SRV |
3556 | struct list_head *mod_head; |
3557 | struct trace_array *tr = ops->private; | |
9ef16693 | 3558 | int ret = -ENOMEM; |
5072c59f | 3559 | |
f04f24fb MH |
3560 | ftrace_ops_init(ops); |
3561 | ||
4eebcc81 SR |
3562 | if (unlikely(ftrace_disabled)) |
3563 | return -ENODEV; | |
3564 | ||
8530dec6 | 3565 | if (tracing_check_open_get_tr(tr)) |
9ef16693 SRV |
3566 | return -ENODEV; |
3567 | ||
5072c59f SR |
3568 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
3569 | if (!iter) | |
9ef16693 | 3570 | goto out; |
5072c59f | 3571 | |
9ef16693 SRV |
3572 | if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) |
3573 | goto out; | |
689fd8b6 | 3574 | |
3f2367ba MH |
3575 | iter->ops = ops; |
3576 | iter->flags = flag; | |
5985ea8b | 3577 | iter->tr = tr; |
3f2367ba | 3578 | |
33b7f99c | 3579 | mutex_lock(&ops->func_hash->regex_lock); |
3f2367ba | 3580 | |
673feb9d | 3581 | if (flag & FTRACE_ITER_NOTRACE) { |
33b7f99c | 3582 | hash = ops->func_hash->notrace_hash; |
5985ea8b | 3583 | mod_head = tr ? &tr->mod_notrace : NULL; |
673feb9d | 3584 | } else { |
33b7f99c | 3585 | hash = ops->func_hash->filter_hash; |
5985ea8b | 3586 | mod_head = tr ? &tr->mod_trace : NULL; |
673feb9d | 3587 | } |
f45948e8 | 3588 | |
5985ea8b SRV |
3589 | iter->mod_list = mod_head; |
3590 | ||
33dc9b12 | 3591 | if (file->f_mode & FMODE_WRITE) { |
ef2fbe16 NK |
3592 | const int size_bits = FTRACE_HASH_DEFAULT_BITS; |
3593 | ||
673feb9d | 3594 | if (file->f_flags & O_TRUNC) { |
ef2fbe16 | 3595 | iter->hash = alloc_ftrace_hash(size_bits); |
673feb9d SRV |
3596 | clear_ftrace_mod_list(mod_head); |
3597 | } else { | |
ef2fbe16 | 3598 | iter->hash = alloc_and_copy_ftrace_hash(size_bits, hash); |
673feb9d | 3599 | } |
ef2fbe16 | 3600 | |
33dc9b12 SR |
3601 | if (!iter->hash) { |
3602 | trace_parser_put(&iter->parser); | |
3f2367ba | 3603 | goto out_unlock; |
33dc9b12 | 3604 | } |
c20489da SRV |
3605 | } else |
3606 | iter->hash = hash; | |
1cf41dd7 | 3607 | |
9ef16693 SRV |
3608 | ret = 0; |
3609 | ||
5072c59f SR |
3610 | if (file->f_mode & FMODE_READ) { |
3611 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
3612 | |
3613 | ret = seq_open(file, &show_ftrace_seq_ops); | |
3614 | if (!ret) { | |
3615 | struct seq_file *m = file->private_data; | |
3616 | m->private = iter; | |
79fe249c | 3617 | } else { |
33dc9b12 SR |
3618 | /* Failed */ |
3619 | free_ftrace_hash(iter->hash); | |
79fe249c | 3620 | trace_parser_put(&iter->parser); |
79fe249c | 3621 | } |
5072c59f SR |
3622 | } else |
3623 | file->private_data = iter; | |
3f2367ba MH |
3624 | |
3625 | out_unlock: | |
33b7f99c | 3626 | mutex_unlock(&ops->func_hash->regex_lock); |
5072c59f | 3627 | |
9ef16693 SRV |
3628 | out: |
3629 | if (ret) { | |
3630 | kfree(iter); | |
3631 | if (tr) | |
3632 | trace_array_put(tr); | |
3633 | } | |
3634 | ||
5072c59f SR |
3635 | return ret; |
3636 | } | |
3637 | ||
41c52c0d SR |
3638 | static int |
3639 | ftrace_filter_open(struct inode *inode, struct file *file) | |
3640 | { | |
e3b3e2e8 SRRH |
3641 | struct ftrace_ops *ops = inode->i_private; |
3642 | ||
17911ff3 | 3643 | /* Checks for tracefs lockdown */ |
e3b3e2e8 | 3644 | return ftrace_regex_open(ops, |
eee8ded1 | 3645 | FTRACE_ITER_FILTER | FTRACE_ITER_DO_PROBES, |
69a3083c | 3646 | inode, file); |
41c52c0d SR |
3647 | } |
3648 | ||
3649 | static int | |
3650 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
3651 | { | |
e3b3e2e8 SRRH |
3652 | struct ftrace_ops *ops = inode->i_private; |
3653 | ||
17911ff3 | 3654 | /* Checks for tracefs lockdown */ |
e3b3e2e8 | 3655 | return ftrace_regex_open(ops, FTRACE_ITER_NOTRACE, |
1cf41dd7 | 3656 | inode, file); |
41c52c0d SR |
3657 | } |
3658 | ||
3ba00929 DS |
3659 | /* Type for quick search ftrace basic regexes (globs) from filter_parse_regex */ |
3660 | struct ftrace_glob { | |
3661 | char *search; | |
3662 | unsigned len; | |
3663 | int type; | |
3664 | }; | |
3665 | ||
7132e2d6 TJB |
3666 | /* |
3667 | * If symbols in an architecture don't correspond exactly to the user-visible | |
3668 | * name of what they represent, it is possible to define this function to | |
3669 | * perform the necessary adjustments. | |
3670 | */ | |
3671 | char * __weak arch_ftrace_match_adjust(char *str, const char *search) | |
3672 | { | |
3673 | return str; | |
3674 | } | |
3675 | ||
3ba00929 | 3676 | static int ftrace_match(char *str, struct ftrace_glob *g) |
9f4801e3 | 3677 | { |
9f4801e3 | 3678 | int matched = 0; |
751e9983 | 3679 | int slen; |
9f4801e3 | 3680 | |
7132e2d6 TJB |
3681 | str = arch_ftrace_match_adjust(str, g->search); |
3682 | ||
3ba00929 | 3683 | switch (g->type) { |
9f4801e3 | 3684 | case MATCH_FULL: |
3ba00929 | 3685 | if (strcmp(str, g->search) == 0) |
9f4801e3 SR |
3686 | matched = 1; |
3687 | break; | |
3688 | case MATCH_FRONT_ONLY: | |
3ba00929 | 3689 | if (strncmp(str, g->search, g->len) == 0) |
9f4801e3 SR |
3690 | matched = 1; |
3691 | break; | |
3692 | case MATCH_MIDDLE_ONLY: | |
3ba00929 | 3693 | if (strstr(str, g->search)) |
9f4801e3 SR |
3694 | matched = 1; |
3695 | break; | |
3696 | case MATCH_END_ONLY: | |
751e9983 | 3697 | slen = strlen(str); |
3ba00929 DS |
3698 | if (slen >= g->len && |
3699 | memcmp(str + slen - g->len, g->search, g->len) == 0) | |
9f4801e3 SR |
3700 | matched = 1; |
3701 | break; | |
60f1d5e3 MH |
3702 | case MATCH_GLOB: |
3703 | if (glob_match(g->search, str)) | |
3704 | matched = 1; | |
3705 | break; | |
9f4801e3 SR |
3706 | } |
3707 | ||
3708 | return matched; | |
3709 | } | |
3710 | ||
b448c4e3 | 3711 | static int |
f0a3b154 | 3712 | enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int clear_filter) |
996e87be | 3713 | { |
b448c4e3 | 3714 | struct ftrace_func_entry *entry; |
b448c4e3 SR |
3715 | int ret = 0; |
3716 | ||
1cf41dd7 | 3717 | entry = ftrace_lookup_ip(hash, rec->ip); |
f0a3b154 | 3718 | if (clear_filter) { |
1cf41dd7 SR |
3719 | /* Do nothing if it doesn't exist */ |
3720 | if (!entry) | |
3721 | return 0; | |
b448c4e3 | 3722 | |
33dc9b12 | 3723 | free_hash_entry(hash, entry); |
1cf41dd7 SR |
3724 | } else { |
3725 | /* Do nothing if it exists */ | |
3726 | if (entry) | |
3727 | return 0; | |
b448c4e3 | 3728 | |
1cf41dd7 | 3729 | ret = add_hash_entry(hash, rec->ip); |
b448c4e3 SR |
3730 | } |
3731 | return ret; | |
996e87be SR |
3732 | } |
3733 | ||
f79b3f33 SRV |
3734 | static int |
3735 | add_rec_by_index(struct ftrace_hash *hash, struct ftrace_glob *func_g, | |
3736 | int clear_filter) | |
3737 | { | |
3738 | long index = simple_strtoul(func_g->search, NULL, 0); | |
3739 | struct ftrace_page *pg; | |
3740 | struct dyn_ftrace *rec; | |
3741 | ||
3742 | /* The index starts at 1 */ | |
3743 | if (--index < 0) | |
3744 | return 0; | |
3745 | ||
3746 | do_for_each_ftrace_rec(pg, rec) { | |
3747 | if (pg->index <= index) { | |
3748 | index -= pg->index; | |
3749 | /* this is a double loop, break goes to the next page */ | |
3750 | break; | |
3751 | } | |
3752 | rec = &pg->records[index]; | |
3753 | enter_record(hash, rec, clear_filter); | |
3754 | return 1; | |
3755 | } while_for_each_ftrace_rec(); | |
3756 | return 0; | |
3757 | } | |
3758 | ||
64e7c440 | 3759 | static int |
0b507e1e DS |
3760 | ftrace_match_record(struct dyn_ftrace *rec, struct ftrace_glob *func_g, |
3761 | struct ftrace_glob *mod_g, int exclude_mod) | |
64e7c440 SR |
3762 | { |
3763 | char str[KSYM_SYMBOL_LEN]; | |
b9df92d2 SR |
3764 | char *modname; |
3765 | ||
3766 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); | |
3767 | ||
0b507e1e DS |
3768 | if (mod_g) { |
3769 | int mod_matches = (modname) ? ftrace_match(modname, mod_g) : 0; | |
3770 | ||
3771 | /* blank module name to match all modules */ | |
3772 | if (!mod_g->len) { | |
3773 | /* blank module globbing: modname xor exclude_mod */ | |
77c0edde | 3774 | if (!exclude_mod != !modname) |
0b507e1e DS |
3775 | goto func_match; |
3776 | return 0; | |
3777 | } | |
3778 | ||
77c0edde SRV |
3779 | /* |
3780 | * exclude_mod is set to trace everything but the given | |
3781 | * module. If it is set and the module matches, then | |
3782 | * return 0. If it is not set, and the module doesn't match | |
3783 | * also return 0. Otherwise, check the function to see if | |
3784 | * that matches. | |
3785 | */ | |
3786 | if (!mod_matches == !exclude_mod) | |
b9df92d2 | 3787 | return 0; |
0b507e1e | 3788 | func_match: |
b9df92d2 | 3789 | /* blank search means to match all funcs in the mod */ |
3ba00929 | 3790 | if (!func_g->len) |
b9df92d2 SR |
3791 | return 1; |
3792 | } | |
64e7c440 | 3793 | |
3ba00929 | 3794 | return ftrace_match(str, func_g); |
64e7c440 SR |
3795 | } |
3796 | ||
1cf41dd7 | 3797 | static int |
3ba00929 | 3798 | match_records(struct ftrace_hash *hash, char *func, int len, char *mod) |
9f4801e3 | 3799 | { |
9f4801e3 SR |
3800 | struct ftrace_page *pg; |
3801 | struct dyn_ftrace *rec; | |
3ba00929 | 3802 | struct ftrace_glob func_g = { .type = MATCH_FULL }; |
0b507e1e DS |
3803 | struct ftrace_glob mod_g = { .type = MATCH_FULL }; |
3804 | struct ftrace_glob *mod_match = (mod) ? &mod_g : NULL; | |
3805 | int exclude_mod = 0; | |
311d16da | 3806 | int found = 0; |
b448c4e3 | 3807 | int ret; |
2e028c4f | 3808 | int clear_filter = 0; |
9f4801e3 | 3809 | |
0b507e1e | 3810 | if (func) { |
3ba00929 DS |
3811 | func_g.type = filter_parse_regex(func, len, &func_g.search, |
3812 | &clear_filter); | |
3813 | func_g.len = strlen(func_g.search); | |
b9df92d2 | 3814 | } |
9f4801e3 | 3815 | |
0b507e1e DS |
3816 | if (mod) { |
3817 | mod_g.type = filter_parse_regex(mod, strlen(mod), | |
3818 | &mod_g.search, &exclude_mod); | |
3819 | mod_g.len = strlen(mod_g.search); | |
b9df92d2 | 3820 | } |
9f4801e3 | 3821 | |
52baf119 | 3822 | mutex_lock(&ftrace_lock); |
265c831c | 3823 | |
b9df92d2 SR |
3824 | if (unlikely(ftrace_disabled)) |
3825 | goto out_unlock; | |
9f4801e3 | 3826 | |
f79b3f33 SRV |
3827 | if (func_g.type == MATCH_INDEX) { |
3828 | found = add_rec_by_index(hash, &func_g, clear_filter); | |
3829 | goto out_unlock; | |
3830 | } | |
3831 | ||
265c831c | 3832 | do_for_each_ftrace_rec(pg, rec) { |
546fece4 SRRH |
3833 | |
3834 | if (rec->flags & FTRACE_FL_DISABLED) | |
3835 | continue; | |
3836 | ||
0b507e1e | 3837 | if (ftrace_match_record(rec, &func_g, mod_match, exclude_mod)) { |
f0a3b154 | 3838 | ret = enter_record(hash, rec, clear_filter); |
b448c4e3 SR |
3839 | if (ret < 0) { |
3840 | found = ret; | |
3841 | goto out_unlock; | |
3842 | } | |
311d16da | 3843 | found = 1; |
265c831c SR |
3844 | } |
3845 | } while_for_each_ftrace_rec(); | |
b9df92d2 | 3846 | out_unlock: |
52baf119 | 3847 | mutex_unlock(&ftrace_lock); |
311d16da LZ |
3848 | |
3849 | return found; | |
5072c59f SR |
3850 | } |
3851 | ||
64e7c440 | 3852 | static int |
1cf41dd7 | 3853 | ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) |
64e7c440 | 3854 | { |
f0a3b154 | 3855 | return match_records(hash, buff, len, NULL); |
64e7c440 SR |
3856 | } |
3857 | ||
e16b35dd SRV |
3858 | static void ftrace_ops_update_code(struct ftrace_ops *ops, |
3859 | struct ftrace_ops_hash *old_hash) | |
3860 | { | |
3861 | struct ftrace_ops *op; | |
3862 | ||
3863 | if (!ftrace_enabled) | |
3864 | return; | |
3865 | ||
3866 | if (ops->flags & FTRACE_OPS_FL_ENABLED) { | |
3867 | ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS, old_hash); | |
3868 | return; | |
3869 | } | |
3870 | ||
3871 | /* | |
3872 | * If this is the shared global_ops filter, then we need to | |
3873 | * check if there is another ops that shares it, is enabled. | |
3874 | * If so, we still need to run the modify code. | |
3875 | */ | |
3876 | if (ops->func_hash != &global_ops.local_hash) | |
3877 | return; | |
3878 | ||
3879 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
3880 | if (op->func_hash == &global_ops.local_hash && | |
3881 | op->flags & FTRACE_OPS_FL_ENABLED) { | |
3882 | ftrace_run_modify_code(op, FTRACE_UPDATE_CALLS, old_hash); | |
3883 | /* Only need to do this once */ | |
3884 | return; | |
3885 | } | |
3886 | } while_for_each_ftrace_op(op); | |
3887 | } | |
3888 | ||
3889 | static int ftrace_hash_move_and_update_ops(struct ftrace_ops *ops, | |
3890 | struct ftrace_hash **orig_hash, | |
3891 | struct ftrace_hash *hash, | |
3892 | int enable) | |
3893 | { | |
3894 | struct ftrace_ops_hash old_hash_ops; | |
3895 | struct ftrace_hash *old_hash; | |
3896 | int ret; | |
3897 | ||
3898 | old_hash = *orig_hash; | |
3899 | old_hash_ops.filter_hash = ops->func_hash->filter_hash; | |
3900 | old_hash_ops.notrace_hash = ops->func_hash->notrace_hash; | |
3901 | ret = ftrace_hash_move(ops, enable, orig_hash, hash); | |
3902 | if (!ret) { | |
3903 | ftrace_ops_update_code(ops, &old_hash_ops); | |
3904 | free_ftrace_hash_rcu(old_hash); | |
3905 | } | |
3906 | return ret; | |
3907 | } | |
64e7c440 | 3908 | |
673feb9d SRV |
3909 | static bool module_exists(const char *module) |
3910 | { | |
3911 | /* All modules have the symbol __this_module */ | |
0f5e5a3a | 3912 | static const char this_mod[] = "__this_module"; |
419e9fe5 | 3913 | char modname[MAX_PARAM_PREFIX_LEN + sizeof(this_mod) + 2]; |
673feb9d SRV |
3914 | unsigned long val; |
3915 | int n; | |
3916 | ||
419e9fe5 | 3917 | n = snprintf(modname, sizeof(modname), "%s:%s", module, this_mod); |
673feb9d | 3918 | |
419e9fe5 | 3919 | if (n > sizeof(modname) - 1) |
673feb9d SRV |
3920 | return false; |
3921 | ||
3922 | val = module_kallsyms_lookup_name(modname); | |
3923 | return val != 0; | |
3924 | } | |
3925 | ||
3926 | static int cache_mod(struct trace_array *tr, | |
3927 | const char *func, char *module, int enable) | |
3928 | { | |
3929 | struct ftrace_mod_load *ftrace_mod, *n; | |
3930 | struct list_head *head = enable ? &tr->mod_trace : &tr->mod_notrace; | |
3931 | int ret; | |
3932 | ||
3933 | mutex_lock(&ftrace_lock); | |
3934 | ||
3935 | /* We do not cache inverse filters */ | |
3936 | if (func[0] == '!') { | |
3937 | func++; | |
3938 | ret = -EINVAL; | |
3939 | ||
3940 | /* Look to remove this hash */ | |
3941 | list_for_each_entry_safe(ftrace_mod, n, head, list) { | |
3942 | if (strcmp(ftrace_mod->module, module) != 0) | |
3943 | continue; | |
3944 | ||
3945 | /* no func matches all */ | |
44925dff | 3946 | if (strcmp(func, "*") == 0 || |
673feb9d SRV |
3947 | (ftrace_mod->func && |
3948 | strcmp(ftrace_mod->func, func) == 0)) { | |
3949 | ret = 0; | |
3950 | free_ftrace_mod(ftrace_mod); | |
3951 | continue; | |
3952 | } | |
3953 | } | |
3954 | goto out; | |
3955 | } | |
3956 | ||
3957 | ret = -EINVAL; | |
3958 | /* We only care about modules that have not been loaded yet */ | |
3959 | if (module_exists(module)) | |
3960 | goto out; | |
3961 | ||
3962 | /* Save this string off, and execute it when the module is loaded */ | |
3963 | ret = ftrace_add_mod(tr, func, module, enable); | |
3964 | out: | |
3965 | mutex_unlock(&ftrace_lock); | |
3966 | ||
3967 | return ret; | |
3968 | } | |
3969 | ||
d7fbf8df SRV |
3970 | static int |
3971 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, | |
3972 | int reset, int enable); | |
3973 | ||
69449bbd | 3974 | #ifdef CONFIG_MODULES |
d7fbf8df SRV |
3975 | static void process_mod_list(struct list_head *head, struct ftrace_ops *ops, |
3976 | char *mod, bool enable) | |
3977 | { | |
3978 | struct ftrace_mod_load *ftrace_mod, *n; | |
3979 | struct ftrace_hash **orig_hash, *new_hash; | |
3980 | LIST_HEAD(process_mods); | |
3981 | char *func; | |
3982 | int ret; | |
3983 | ||
3984 | mutex_lock(&ops->func_hash->regex_lock); | |
3985 | ||
3986 | if (enable) | |
3987 | orig_hash = &ops->func_hash->filter_hash; | |
3988 | else | |
3989 | orig_hash = &ops->func_hash->notrace_hash; | |
3990 | ||
3991 | new_hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, | |
3992 | *orig_hash); | |
3993 | if (!new_hash) | |
3b58a3c7 | 3994 | goto out; /* warn? */ |
d7fbf8df SRV |
3995 | |
3996 | mutex_lock(&ftrace_lock); | |
3997 | ||
3998 | list_for_each_entry_safe(ftrace_mod, n, head, list) { | |
3999 | ||
4000 | if (strcmp(ftrace_mod->module, mod) != 0) | |
4001 | continue; | |
4002 | ||
4003 | if (ftrace_mod->func) | |
4004 | func = kstrdup(ftrace_mod->func, GFP_KERNEL); | |
4005 | else | |
4006 | func = kstrdup("*", GFP_KERNEL); | |
4007 | ||
4008 | if (!func) /* warn? */ | |
4009 | continue; | |
4010 | ||
4011 | list_del(&ftrace_mod->list); | |
4012 | list_add(&ftrace_mod->list, &process_mods); | |
4013 | ||
4014 | /* Use the newly allocated func, as it may be "*" */ | |
4015 | kfree(ftrace_mod->func); | |
4016 | ftrace_mod->func = func; | |
4017 | } | |
4018 | ||
4019 | mutex_unlock(&ftrace_lock); | |
4020 | ||
4021 | list_for_each_entry_safe(ftrace_mod, n, &process_mods, list) { | |
4022 | ||
4023 | func = ftrace_mod->func; | |
4024 | ||
4025 | /* Grabs ftrace_lock, which is why we have this extra step */ | |
4026 | match_records(new_hash, func, strlen(func), mod); | |
4027 | free_ftrace_mod(ftrace_mod); | |
4028 | } | |
4029 | ||
8c08f0d5 SRV |
4030 | if (enable && list_empty(head)) |
4031 | new_hash->flags &= ~FTRACE_HASH_FL_MOD; | |
4032 | ||
d7fbf8df SRV |
4033 | mutex_lock(&ftrace_lock); |
4034 | ||
4035 | ret = ftrace_hash_move_and_update_ops(ops, orig_hash, | |
4036 | new_hash, enable); | |
4037 | mutex_unlock(&ftrace_lock); | |
4038 | ||
3b58a3c7 | 4039 | out: |
d7fbf8df SRV |
4040 | mutex_unlock(&ops->func_hash->regex_lock); |
4041 | ||
4042 | free_ftrace_hash(new_hash); | |
4043 | } | |
4044 | ||
4045 | static void process_cached_mods(const char *mod_name) | |
4046 | { | |
4047 | struct trace_array *tr; | |
4048 | char *mod; | |
4049 | ||
4050 | mod = kstrdup(mod_name, GFP_KERNEL); | |
4051 | if (!mod) | |
4052 | return; | |
4053 | ||
4054 | mutex_lock(&trace_types_lock); | |
4055 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
4056 | if (!list_empty(&tr->mod_trace)) | |
4057 | process_mod_list(&tr->mod_trace, tr->ops, mod, true); | |
4058 | if (!list_empty(&tr->mod_notrace)) | |
4059 | process_mod_list(&tr->mod_notrace, tr->ops, mod, false); | |
4060 | } | |
4061 | mutex_unlock(&trace_types_lock); | |
4062 | ||
4063 | kfree(mod); | |
4064 | } | |
69449bbd | 4065 | #endif |
d7fbf8df | 4066 | |
f6180773 SR |
4067 | /* |
4068 | * We register the module command as a template to show others how | |
4069 | * to register the a command as well. | |
4070 | */ | |
4071 | ||
4072 | static int | |
04ec7bb6 | 4073 | ftrace_mod_callback(struct trace_array *tr, struct ftrace_hash *hash, |
673feb9d | 4074 | char *func_orig, char *cmd, char *module, int enable) |
f6180773 | 4075 | { |
673feb9d | 4076 | char *func; |
5e3949f0 | 4077 | int ret; |
f6180773 | 4078 | |
673feb9d SRV |
4079 | /* match_records() modifies func, and we need the original */ |
4080 | func = kstrdup(func_orig, GFP_KERNEL); | |
4081 | if (!func) | |
4082 | return -ENOMEM; | |
4083 | ||
f6180773 SR |
4084 | /* |
4085 | * cmd == 'mod' because we only registered this func | |
4086 | * for the 'mod' ftrace_func_command. | |
4087 | * But if you register one func with multiple commands, | |
4088 | * you can tell which command was used by the cmd | |
4089 | * parameter. | |
4090 | */ | |
f0a3b154 | 4091 | ret = match_records(hash, func, strlen(func), module); |
673feb9d SRV |
4092 | kfree(func); |
4093 | ||
b448c4e3 | 4094 | if (!ret) |
673feb9d | 4095 | return cache_mod(tr, func_orig, module, enable); |
b448c4e3 SR |
4096 | if (ret < 0) |
4097 | return ret; | |
b448c4e3 | 4098 | return 0; |
f6180773 SR |
4099 | } |
4100 | ||
4101 | static struct ftrace_func_command ftrace_mod_cmd = { | |
4102 | .name = "mod", | |
4103 | .func = ftrace_mod_callback, | |
4104 | }; | |
4105 | ||
4106 | static int __init ftrace_mod_cmd_init(void) | |
4107 | { | |
4108 | return register_ftrace_command(&ftrace_mod_cmd); | |
4109 | } | |
6f415672 | 4110 | core_initcall(ftrace_mod_cmd_init); |
f6180773 | 4111 | |
2f5f6ad9 | 4112 | static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 4113 | struct ftrace_ops *op, struct pt_regs *pt_regs) |
59df055f | 4114 | { |
eee8ded1 | 4115 | struct ftrace_probe_ops *probe_ops; |
7b60f3d8 | 4116 | struct ftrace_func_probe *probe; |
59df055f | 4117 | |
7b60f3d8 SRV |
4118 | probe = container_of(op, struct ftrace_func_probe, ops); |
4119 | probe_ops = probe->probe_ops; | |
59df055f SR |
4120 | |
4121 | /* | |
4122 | * Disable preemption for these calls to prevent a RCU grace | |
4123 | * period. This syncs the hash iteration and freeing of items | |
4124 | * on the hash. rcu_read_lock is too dangerous here. | |
4125 | */ | |
5168ae50 | 4126 | preempt_disable_notrace(); |
6e444319 | 4127 | probe_ops->func(ip, parent_ip, probe->tr, probe_ops, probe->data); |
5168ae50 | 4128 | preempt_enable_notrace(); |
59df055f SR |
4129 | } |
4130 | ||
41794f19 SRV |
4131 | struct ftrace_func_map { |
4132 | struct ftrace_func_entry entry; | |
4133 | void *data; | |
59df055f SR |
4134 | }; |
4135 | ||
41794f19 SRV |
4136 | struct ftrace_func_mapper { |
4137 | struct ftrace_hash hash; | |
4138 | }; | |
59df055f | 4139 | |
41794f19 SRV |
4140 | /** |
4141 | * allocate_ftrace_func_mapper - allocate a new ftrace_func_mapper | |
4142 | * | |
4143 | * Returns a ftrace_func_mapper descriptor that can be used to map ips to data. | |
4144 | */ | |
4145 | struct ftrace_func_mapper *allocate_ftrace_func_mapper(void) | |
59df055f | 4146 | { |
41794f19 | 4147 | struct ftrace_hash *hash; |
59df055f | 4148 | |
41794f19 SRV |
4149 | /* |
4150 | * The mapper is simply a ftrace_hash, but since the entries | |
4151 | * in the hash are not ftrace_func_entry type, we define it | |
4152 | * as a separate structure. | |
4153 | */ | |
4154 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); | |
4155 | return (struct ftrace_func_mapper *)hash; | |
4156 | } | |
59df055f | 4157 | |
41794f19 SRV |
4158 | /** |
4159 | * ftrace_func_mapper_find_ip - Find some data mapped to an ip | |
4160 | * @mapper: The mapper that has the ip maps | |
4161 | * @ip: the instruction pointer to find the data for | |
4162 | * | |
4163 | * Returns the data mapped to @ip if found otherwise NULL. The return | |
4164 | * is actually the address of the mapper data pointer. The address is | |
4165 | * returned for use cases where the data is no bigger than a long, and | |
4166 | * the user can use the data pointer as its data instead of having to | |
4167 | * allocate more memory for the reference. | |
4168 | */ | |
4169 | void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper, | |
4170 | unsigned long ip) | |
4171 | { | |
4172 | struct ftrace_func_entry *entry; | |
4173 | struct ftrace_func_map *map; | |
59df055f | 4174 | |
41794f19 SRV |
4175 | entry = ftrace_lookup_ip(&mapper->hash, ip); |
4176 | if (!entry) | |
4177 | return NULL; | |
b848914c | 4178 | |
41794f19 SRV |
4179 | map = (struct ftrace_func_map *)entry; |
4180 | return &map->data; | |
59df055f SR |
4181 | } |
4182 | ||
41794f19 SRV |
4183 | /** |
4184 | * ftrace_func_mapper_add_ip - Map some data to an ip | |
4185 | * @mapper: The mapper that has the ip maps | |
4186 | * @ip: The instruction pointer address to map @data to | |
4187 | * @data: The data to map to @ip | |
4188 | * | |
4189 | * Returns 0 on succes otherwise an error. | |
4190 | */ | |
4191 | int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper, | |
4192 | unsigned long ip, void *data) | |
59df055f | 4193 | { |
41794f19 SRV |
4194 | struct ftrace_func_entry *entry; |
4195 | struct ftrace_func_map *map; | |
59df055f | 4196 | |
41794f19 SRV |
4197 | entry = ftrace_lookup_ip(&mapper->hash, ip); |
4198 | if (entry) | |
4199 | return -EBUSY; | |
59df055f | 4200 | |
41794f19 SRV |
4201 | map = kmalloc(sizeof(*map), GFP_KERNEL); |
4202 | if (!map) | |
4203 | return -ENOMEM; | |
59df055f | 4204 | |
41794f19 SRV |
4205 | map->entry.ip = ip; |
4206 | map->data = data; | |
b848914c | 4207 | |
41794f19 | 4208 | __add_hash_entry(&mapper->hash, &map->entry); |
59df055f | 4209 | |
41794f19 SRV |
4210 | return 0; |
4211 | } | |
59df055f | 4212 | |
41794f19 SRV |
4213 | /** |
4214 | * ftrace_func_mapper_remove_ip - Remove an ip from the mapping | |
4215 | * @mapper: The mapper that has the ip maps | |
4216 | * @ip: The instruction pointer address to remove the data from | |
4217 | * | |
4218 | * Returns the data if it is found, otherwise NULL. | |
4219 | * Note, if the data pointer is used as the data itself, (see | |
4220 | * ftrace_func_mapper_find_ip(), then the return value may be meaningless, | |
4221 | * if the data pointer was set to zero. | |
4222 | */ | |
4223 | void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper, | |
4224 | unsigned long ip) | |
59df055f | 4225 | { |
41794f19 SRV |
4226 | struct ftrace_func_entry *entry; |
4227 | struct ftrace_func_map *map; | |
4228 | void *data; | |
4229 | ||
4230 | entry = ftrace_lookup_ip(&mapper->hash, ip); | |
4231 | if (!entry) | |
4232 | return NULL; | |
4233 | ||
4234 | map = (struct ftrace_func_map *)entry; | |
4235 | data = map->data; | |
4236 | ||
4237 | remove_hash_entry(&mapper->hash, entry); | |
59df055f | 4238 | kfree(entry); |
41794f19 SRV |
4239 | |
4240 | return data; | |
4241 | } | |
4242 | ||
4243 | /** | |
4244 | * free_ftrace_func_mapper - free a mapping of ips and data | |
4245 | * @mapper: The mapper that has the ip maps | |
4246 | * @free_func: A function to be called on each data item. | |
4247 | * | |
4248 | * This is used to free the function mapper. The @free_func is optional | |
4249 | * and can be used if the data needs to be freed as well. | |
4250 | */ | |
4251 | void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper, | |
4252 | ftrace_mapper_func free_func) | |
4253 | { | |
4254 | struct ftrace_func_entry *entry; | |
4255 | struct ftrace_func_map *map; | |
4256 | struct hlist_head *hhd; | |
04e03d9a WL |
4257 | int size, i; |
4258 | ||
4259 | if (!mapper) | |
4260 | return; | |
41794f19 SRV |
4261 | |
4262 | if (free_func && mapper->hash.count) { | |
04e03d9a | 4263 | size = 1 << mapper->hash.size_bits; |
41794f19 SRV |
4264 | for (i = 0; i < size; i++) { |
4265 | hhd = &mapper->hash.buckets[i]; | |
4266 | hlist_for_each_entry(entry, hhd, hlist) { | |
4267 | map = (struct ftrace_func_map *)entry; | |
4268 | free_func(map); | |
4269 | } | |
4270 | } | |
4271 | } | |
4272 | free_ftrace_hash(&mapper->hash); | |
4273 | } | |
4274 | ||
7b60f3d8 SRV |
4275 | static void release_probe(struct ftrace_func_probe *probe) |
4276 | { | |
4277 | struct ftrace_probe_ops *probe_ops; | |
4278 | ||
4279 | mutex_lock(&ftrace_lock); | |
4280 | ||
4281 | WARN_ON(probe->ref <= 0); | |
4282 | ||
4283 | /* Subtract the ref that was used to protect this instance */ | |
4284 | probe->ref--; | |
4285 | ||
4286 | if (!probe->ref) { | |
4287 | probe_ops = probe->probe_ops; | |
6e444319 SRV |
4288 | /* |
4289 | * Sending zero as ip tells probe_ops to free | |
4290 | * the probe->data itself | |
4291 | */ | |
4292 | if (probe_ops->free) | |
4293 | probe_ops->free(probe_ops, probe->tr, 0, probe->data); | |
7b60f3d8 SRV |
4294 | list_del(&probe->list); |
4295 | kfree(probe); | |
4296 | } | |
4297 | mutex_unlock(&ftrace_lock); | |
4298 | } | |
4299 | ||
4300 | static void acquire_probe_locked(struct ftrace_func_probe *probe) | |
4301 | { | |
4302 | /* | |
4303 | * Add one ref to keep it from being freed when releasing the | |
4304 | * ftrace_lock mutex. | |
4305 | */ | |
4306 | probe->ref++; | |
59df055f SR |
4307 | } |
4308 | ||
59df055f | 4309 | int |
04ec7bb6 | 4310 | register_ftrace_function_probe(char *glob, struct trace_array *tr, |
7b60f3d8 SRV |
4311 | struct ftrace_probe_ops *probe_ops, |
4312 | void *data) | |
59df055f | 4313 | { |
1ec3a81a | 4314 | struct ftrace_func_entry *entry; |
7b60f3d8 | 4315 | struct ftrace_func_probe *probe; |
1ec3a81a SRV |
4316 | struct ftrace_hash **orig_hash; |
4317 | struct ftrace_hash *old_hash; | |
e1df4cb6 | 4318 | struct ftrace_hash *hash; |
59df055f | 4319 | int count = 0; |
1ec3a81a | 4320 | int size; |
e1df4cb6 | 4321 | int ret; |
1ec3a81a | 4322 | int i; |
59df055f | 4323 | |
04ec7bb6 | 4324 | if (WARN_ON(!tr)) |
59df055f SR |
4325 | return -EINVAL; |
4326 | ||
1ec3a81a SRV |
4327 | /* We do not support '!' for function probes */ |
4328 | if (WARN_ON(glob[0] == '!')) | |
59df055f | 4329 | return -EINVAL; |
59df055f | 4330 | |
7485058e | 4331 | |
7b60f3d8 SRV |
4332 | mutex_lock(&ftrace_lock); |
4333 | /* Check if the probe_ops is already registered */ | |
4334 | list_for_each_entry(probe, &tr->func_probes, list) { | |
4335 | if (probe->probe_ops == probe_ops) | |
4336 | break; | |
e1df4cb6 | 4337 | } |
7b60f3d8 SRV |
4338 | if (&probe->list == &tr->func_probes) { |
4339 | probe = kzalloc(sizeof(*probe), GFP_KERNEL); | |
4340 | if (!probe) { | |
4341 | mutex_unlock(&ftrace_lock); | |
4342 | return -ENOMEM; | |
4343 | } | |
4344 | probe->probe_ops = probe_ops; | |
4345 | probe->ops.func = function_trace_probe_call; | |
4346 | probe->tr = tr; | |
4347 | ftrace_ops_init(&probe->ops); | |
4348 | list_add(&probe->list, &tr->func_probes); | |
e1df4cb6 | 4349 | } |
59df055f | 4350 | |
7b60f3d8 | 4351 | acquire_probe_locked(probe); |
5ae0bf59 | 4352 | |
7b60f3d8 | 4353 | mutex_unlock(&ftrace_lock); |
59df055f | 4354 | |
372e0d01 SRV |
4355 | /* |
4356 | * Note, there's a small window here that the func_hash->filter_hash | |
4357 | * may be NULL or empty. Need to be carefule when reading the loop. | |
4358 | */ | |
7b60f3d8 | 4359 | mutex_lock(&probe->ops.func_hash->regex_lock); |
546fece4 | 4360 | |
7b60f3d8 | 4361 | orig_hash = &probe->ops.func_hash->filter_hash; |
1ec3a81a SRV |
4362 | old_hash = *orig_hash; |
4363 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash); | |
59df055f | 4364 | |
5b0022dd NR |
4365 | if (!hash) { |
4366 | ret = -ENOMEM; | |
4367 | goto out; | |
4368 | } | |
4369 | ||
1ec3a81a | 4370 | ret = ftrace_match_records(hash, glob, strlen(glob)); |
59df055f | 4371 | |
1ec3a81a SRV |
4372 | /* Nothing found? */ |
4373 | if (!ret) | |
4374 | ret = -EINVAL; | |
59df055f | 4375 | |
1ec3a81a SRV |
4376 | if (ret < 0) |
4377 | goto out; | |
59df055f | 4378 | |
1ec3a81a SRV |
4379 | size = 1 << hash->size_bits; |
4380 | for (i = 0; i < size; i++) { | |
4381 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { | |
4382 | if (ftrace_lookup_ip(old_hash, entry->ip)) | |
59df055f | 4383 | continue; |
1ec3a81a SRV |
4384 | /* |
4385 | * The caller might want to do something special | |
4386 | * for each function we find. We call the callback | |
4387 | * to give the caller an opportunity to do so. | |
4388 | */ | |
7b60f3d8 SRV |
4389 | if (probe_ops->init) { |
4390 | ret = probe_ops->init(probe_ops, tr, | |
6e444319 SRV |
4391 | entry->ip, data, |
4392 | &probe->data); | |
4393 | if (ret < 0) { | |
4394 | if (probe_ops->free && count) | |
4395 | probe_ops->free(probe_ops, tr, | |
4396 | 0, probe->data); | |
4397 | probe->data = NULL; | |
eee8ded1 | 4398 | goto out; |
6e444319 | 4399 | } |
59df055f | 4400 | } |
1ec3a81a | 4401 | count++; |
59df055f | 4402 | } |
1ec3a81a | 4403 | } |
59df055f | 4404 | |
1ec3a81a | 4405 | mutex_lock(&ftrace_lock); |
59df055f | 4406 | |
7b60f3d8 SRV |
4407 | if (!count) { |
4408 | /* Nothing was added? */ | |
4409 | ret = -EINVAL; | |
4410 | goto out_unlock; | |
4411 | } | |
e1df4cb6 | 4412 | |
7b60f3d8 SRV |
4413 | ret = ftrace_hash_move_and_update_ops(&probe->ops, orig_hash, |
4414 | hash, 1); | |
1ec3a81a | 4415 | if (ret < 0) |
8d70725e | 4416 | goto err_unlock; |
8252ecf3 | 4417 | |
7b60f3d8 SRV |
4418 | /* One ref for each new function traced */ |
4419 | probe->ref += count; | |
8252ecf3 | 4420 | |
7b60f3d8 SRV |
4421 | if (!(probe->ops.flags & FTRACE_OPS_FL_ENABLED)) |
4422 | ret = ftrace_startup(&probe->ops, 0); | |
e1df4cb6 | 4423 | |
59df055f | 4424 | out_unlock: |
5ae0bf59 | 4425 | mutex_unlock(&ftrace_lock); |
8252ecf3 | 4426 | |
3296fc4e | 4427 | if (!ret) |
1ec3a81a | 4428 | ret = count; |
5ae0bf59 | 4429 | out: |
7b60f3d8 | 4430 | mutex_unlock(&probe->ops.func_hash->regex_lock); |
e1df4cb6 | 4431 | free_ftrace_hash(hash); |
59df055f | 4432 | |
7b60f3d8 | 4433 | release_probe(probe); |
59df055f | 4434 | |
1ec3a81a | 4435 | return ret; |
59df055f | 4436 | |
8d70725e | 4437 | err_unlock: |
7b60f3d8 | 4438 | if (!probe_ops->free || !count) |
8d70725e SRV |
4439 | goto out_unlock; |
4440 | ||
4441 | /* Failed to do the move, need to call the free functions */ | |
4442 | for (i = 0; i < size; i++) { | |
4443 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { | |
4444 | if (ftrace_lookup_ip(old_hash, entry->ip)) | |
4445 | continue; | |
6e444319 | 4446 | probe_ops->free(probe_ops, tr, entry->ip, probe->data); |
8d70725e SRV |
4447 | } |
4448 | } | |
4449 | goto out_unlock; | |
59df055f SR |
4450 | } |
4451 | ||
d3d532d7 | 4452 | int |
7b60f3d8 SRV |
4453 | unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr, |
4454 | struct ftrace_probe_ops *probe_ops) | |
59df055f | 4455 | { |
82cc4fc2 | 4456 | struct ftrace_ops_hash old_hash_ops; |
eee8ded1 | 4457 | struct ftrace_func_entry *entry; |
7b60f3d8 | 4458 | struct ftrace_func_probe *probe; |
3ba00929 | 4459 | struct ftrace_glob func_g; |
1ec3a81a SRV |
4460 | struct ftrace_hash **orig_hash; |
4461 | struct ftrace_hash *old_hash; | |
1ec3a81a | 4462 | struct ftrace_hash *hash = NULL; |
b67bfe0d | 4463 | struct hlist_node *tmp; |
eee8ded1 | 4464 | struct hlist_head hhd; |
59df055f | 4465 | char str[KSYM_SYMBOL_LEN]; |
7b60f3d8 SRV |
4466 | int count = 0; |
4467 | int i, ret = -ENODEV; | |
eee8ded1 | 4468 | int size; |
59df055f | 4469 | |
cbab567c | 4470 | if (!glob || !strlen(glob) || !strcmp(glob, "*")) |
3ba00929 | 4471 | func_g.search = NULL; |
cbab567c | 4472 | else { |
59df055f SR |
4473 | int not; |
4474 | ||
3ba00929 DS |
4475 | func_g.type = filter_parse_regex(glob, strlen(glob), |
4476 | &func_g.search, ¬); | |
4477 | func_g.len = strlen(func_g.search); | |
59df055f | 4478 | |
b6887d79 | 4479 | /* we do not support '!' for function probes */ |
59df055f | 4480 | if (WARN_ON(not)) |
d3d532d7 | 4481 | return -EINVAL; |
59df055f SR |
4482 | } |
4483 | ||
7b60f3d8 SRV |
4484 | mutex_lock(&ftrace_lock); |
4485 | /* Check if the probe_ops is already registered */ | |
4486 | list_for_each_entry(probe, &tr->func_probes, list) { | |
4487 | if (probe->probe_ops == probe_ops) | |
4488 | break; | |
59df055f | 4489 | } |
7b60f3d8 SRV |
4490 | if (&probe->list == &tr->func_probes) |
4491 | goto err_unlock_ftrace; | |
4492 | ||
4493 | ret = -EINVAL; | |
4494 | if (!(probe->ops.flags & FTRACE_OPS_FL_INITIALIZED)) | |
4495 | goto err_unlock_ftrace; | |
4496 | ||
4497 | acquire_probe_locked(probe); | |
4498 | ||
4499 | mutex_unlock(&ftrace_lock); | |
59df055f | 4500 | |
7b60f3d8 | 4501 | mutex_lock(&probe->ops.func_hash->regex_lock); |
1ec3a81a | 4502 | |
7b60f3d8 | 4503 | orig_hash = &probe->ops.func_hash->filter_hash; |
1ec3a81a SRV |
4504 | old_hash = *orig_hash; |
4505 | ||
1ec3a81a SRV |
4506 | if (ftrace_hash_empty(old_hash)) |
4507 | goto out_unlock; | |
e1df4cb6 | 4508 | |
82cc4fc2 SRV |
4509 | old_hash_ops.filter_hash = old_hash; |
4510 | /* Probes only have filters */ | |
4511 | old_hash_ops.notrace_hash = NULL; | |
4512 | ||
d3d532d7 | 4513 | ret = -ENOMEM; |
1ec3a81a | 4514 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash); |
e1df4cb6 | 4515 | if (!hash) |
e1df4cb6 SRRH |
4516 | goto out_unlock; |
4517 | ||
eee8ded1 | 4518 | INIT_HLIST_HEAD(&hhd); |
59df055f | 4519 | |
eee8ded1 SRV |
4520 | size = 1 << hash->size_bits; |
4521 | for (i = 0; i < size; i++) { | |
4522 | hlist_for_each_entry_safe(entry, tmp, &hash->buckets[i], hlist) { | |
59df055f | 4523 | |
3ba00929 | 4524 | if (func_g.search) { |
59df055f SR |
4525 | kallsyms_lookup(entry->ip, NULL, NULL, |
4526 | NULL, str); | |
3ba00929 | 4527 | if (!ftrace_match(str, &func_g)) |
59df055f SR |
4528 | continue; |
4529 | } | |
7b60f3d8 | 4530 | count++; |
eee8ded1 SRV |
4531 | remove_hash_entry(hash, entry); |
4532 | hlist_add_head(&entry->hlist, &hhd); | |
59df055f SR |
4533 | } |
4534 | } | |
d3d532d7 SRV |
4535 | |
4536 | /* Nothing found? */ | |
7b60f3d8 | 4537 | if (!count) { |
d3d532d7 SRV |
4538 | ret = -EINVAL; |
4539 | goto out_unlock; | |
4540 | } | |
4541 | ||
3f2367ba | 4542 | mutex_lock(&ftrace_lock); |
1ec3a81a | 4543 | |
7b60f3d8 | 4544 | WARN_ON(probe->ref < count); |
eee8ded1 | 4545 | |
7b60f3d8 | 4546 | probe->ref -= count; |
1ec3a81a | 4547 | |
7b60f3d8 SRV |
4548 | if (ftrace_hash_empty(hash)) |
4549 | ftrace_shutdown(&probe->ops, 0); | |
4550 | ||
4551 | ret = ftrace_hash_move_and_update_ops(&probe->ops, orig_hash, | |
1ec3a81a | 4552 | hash, 1); |
82cc4fc2 SRV |
4553 | |
4554 | /* still need to update the function call sites */ | |
1ec3a81a | 4555 | if (ftrace_enabled && !ftrace_hash_empty(hash)) |
7b60f3d8 | 4556 | ftrace_run_modify_code(&probe->ops, FTRACE_UPDATE_CALLS, |
82cc4fc2 | 4557 | &old_hash_ops); |
74401729 | 4558 | synchronize_rcu(); |
3296fc4e | 4559 | |
eee8ded1 SRV |
4560 | hlist_for_each_entry_safe(entry, tmp, &hhd, hlist) { |
4561 | hlist_del(&entry->hlist); | |
7b60f3d8 | 4562 | if (probe_ops->free) |
6e444319 | 4563 | probe_ops->free(probe_ops, tr, entry->ip, probe->data); |
eee8ded1 | 4564 | kfree(entry); |
7818b388 | 4565 | } |
3f2367ba | 4566 | mutex_unlock(&ftrace_lock); |
3ba00929 | 4567 | |
e1df4cb6 | 4568 | out_unlock: |
7b60f3d8 | 4569 | mutex_unlock(&probe->ops.func_hash->regex_lock); |
e1df4cb6 | 4570 | free_ftrace_hash(hash); |
59df055f | 4571 | |
7b60f3d8 | 4572 | release_probe(probe); |
59df055f | 4573 | |
7b60f3d8 | 4574 | return ret; |
59df055f | 4575 | |
7b60f3d8 SRV |
4576 | err_unlock_ftrace: |
4577 | mutex_unlock(&ftrace_lock); | |
d3d532d7 | 4578 | return ret; |
59df055f SR |
4579 | } |
4580 | ||
a0e6369e NR |
4581 | void clear_ftrace_function_probes(struct trace_array *tr) |
4582 | { | |
4583 | struct ftrace_func_probe *probe, *n; | |
4584 | ||
4585 | list_for_each_entry_safe(probe, n, &tr->func_probes, list) | |
4586 | unregister_ftrace_function_probe_func(NULL, tr, probe->probe_ops); | |
4587 | } | |
4588 | ||
f6180773 SR |
4589 | static LIST_HEAD(ftrace_commands); |
4590 | static DEFINE_MUTEX(ftrace_cmd_mutex); | |
4591 | ||
38de93ab TZ |
4592 | /* |
4593 | * Currently we only register ftrace commands from __init, so mark this | |
4594 | * __init too. | |
4595 | */ | |
4596 | __init int register_ftrace_command(struct ftrace_func_command *cmd) | |
f6180773 SR |
4597 | { |
4598 | struct ftrace_func_command *p; | |
4599 | int ret = 0; | |
4600 | ||
4601 | mutex_lock(&ftrace_cmd_mutex); | |
4602 | list_for_each_entry(p, &ftrace_commands, list) { | |
4603 | if (strcmp(cmd->name, p->name) == 0) { | |
4604 | ret = -EBUSY; | |
4605 | goto out_unlock; | |
4606 | } | |
4607 | } | |
4608 | list_add(&cmd->list, &ftrace_commands); | |
4609 | out_unlock: | |
4610 | mutex_unlock(&ftrace_cmd_mutex); | |
4611 | ||
4612 | return ret; | |
4613 | } | |
4614 | ||
38de93ab TZ |
4615 | /* |
4616 | * Currently we only unregister ftrace commands from __init, so mark | |
4617 | * this __init too. | |
4618 | */ | |
4619 | __init int unregister_ftrace_command(struct ftrace_func_command *cmd) | |
f6180773 SR |
4620 | { |
4621 | struct ftrace_func_command *p, *n; | |
4622 | int ret = -ENODEV; | |
4623 | ||
4624 | mutex_lock(&ftrace_cmd_mutex); | |
4625 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { | |
4626 | if (strcmp(cmd->name, p->name) == 0) { | |
4627 | ret = 0; | |
4628 | list_del_init(&p->list); | |
4629 | goto out_unlock; | |
4630 | } | |
4631 | } | |
4632 | out_unlock: | |
4633 | mutex_unlock(&ftrace_cmd_mutex); | |
4634 | ||
4635 | return ret; | |
4636 | } | |
4637 | ||
04ec7bb6 | 4638 | static int ftrace_process_regex(struct ftrace_iterator *iter, |
33dc9b12 | 4639 | char *buff, int len, int enable) |
64e7c440 | 4640 | { |
04ec7bb6 | 4641 | struct ftrace_hash *hash = iter->hash; |
d2afd57a | 4642 | struct trace_array *tr = iter->ops->private; |
f6180773 | 4643 | char *func, *command, *next = buff; |
6a24a244 | 4644 | struct ftrace_func_command *p; |
0aff1c0c | 4645 | int ret = -EINVAL; |
64e7c440 SR |
4646 | |
4647 | func = strsep(&next, ":"); | |
4648 | ||
4649 | if (!next) { | |
1cf41dd7 | 4650 | ret = ftrace_match_records(hash, func, len); |
b448c4e3 SR |
4651 | if (!ret) |
4652 | ret = -EINVAL; | |
4653 | if (ret < 0) | |
4654 | return ret; | |
4655 | return 0; | |
64e7c440 SR |
4656 | } |
4657 | ||
f6180773 | 4658 | /* command found */ |
64e7c440 SR |
4659 | |
4660 | command = strsep(&next, ":"); | |
4661 | ||
f6180773 SR |
4662 | mutex_lock(&ftrace_cmd_mutex); |
4663 | list_for_each_entry(p, &ftrace_commands, list) { | |
4664 | if (strcmp(p->name, command) == 0) { | |
04ec7bb6 | 4665 | ret = p->func(tr, hash, func, command, next, enable); |
f6180773 SR |
4666 | goto out_unlock; |
4667 | } | |
64e7c440 | 4668 | } |
f6180773 SR |
4669 | out_unlock: |
4670 | mutex_unlock(&ftrace_cmd_mutex); | |
64e7c440 | 4671 | |
f6180773 | 4672 | return ret; |
64e7c440 SR |
4673 | } |
4674 | ||
e309b41d | 4675 | static ssize_t |
41c52c0d SR |
4676 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
4677 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
4678 | { |
4679 | struct ftrace_iterator *iter; | |
689fd8b6 | 4680 | struct trace_parser *parser; |
4681 | ssize_t ret, read; | |
5072c59f | 4682 | |
4ba7978e | 4683 | if (!cnt) |
5072c59f SR |
4684 | return 0; |
4685 | ||
5072c59f SR |
4686 | if (file->f_mode & FMODE_READ) { |
4687 | struct seq_file *m = file->private_data; | |
4688 | iter = m->private; | |
4689 | } else | |
4690 | iter = file->private_data; | |
4691 | ||
f04f24fb | 4692 | if (unlikely(ftrace_disabled)) |
3f2367ba MH |
4693 | return -ENODEV; |
4694 | ||
4695 | /* iter->hash is a local copy, so we don't need regex_lock */ | |
f04f24fb | 4696 | |
689fd8b6 | 4697 | parser = &iter->parser; |
4698 | read = trace_get_user(parser, ubuf, cnt, ppos); | |
5072c59f | 4699 | |
4ba7978e | 4700 | if (read >= 0 && trace_parser_loaded(parser) && |
689fd8b6 | 4701 | !trace_parser_cont(parser)) { |
04ec7bb6 | 4702 | ret = ftrace_process_regex(iter, parser->buffer, |
689fd8b6 | 4703 | parser->idx, enable); |
313254a9 | 4704 | trace_parser_clear(parser); |
7c088b51 | 4705 | if (ret < 0) |
3f2367ba | 4706 | goto out; |
eda1e328 | 4707 | } |
5072c59f | 4708 | |
5072c59f | 4709 | ret = read; |
3f2367ba | 4710 | out: |
5072c59f SR |
4711 | return ret; |
4712 | } | |
4713 | ||
fc13cb0c | 4714 | ssize_t |
41c52c0d SR |
4715 | ftrace_filter_write(struct file *file, const char __user *ubuf, |
4716 | size_t cnt, loff_t *ppos) | |
4717 | { | |
4718 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
4719 | } | |
4720 | ||
fc13cb0c | 4721 | ssize_t |
41c52c0d SR |
4722 | ftrace_notrace_write(struct file *file, const char __user *ubuf, |
4723 | size_t cnt, loff_t *ppos) | |
4724 | { | |
4725 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
4726 | } | |
4727 | ||
33dc9b12 | 4728 | static int |
647664ea MH |
4729 | ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) |
4730 | { | |
4731 | struct ftrace_func_entry *entry; | |
4732 | ||
4733 | if (!ftrace_location(ip)) | |
4734 | return -EINVAL; | |
4735 | ||
4736 | if (remove) { | |
4737 | entry = ftrace_lookup_ip(hash, ip); | |
4738 | if (!entry) | |
4739 | return -ENOENT; | |
4740 | free_hash_entry(hash, entry); | |
4741 | return 0; | |
4742 | } | |
4743 | ||
4744 | return add_hash_entry(hash, ip); | |
4745 | } | |
4746 | ||
4747 | static int | |
4748 | ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, | |
4749 | unsigned long ip, int remove, int reset, int enable) | |
41c52c0d | 4750 | { |
33dc9b12 | 4751 | struct ftrace_hash **orig_hash; |
f45948e8 | 4752 | struct ftrace_hash *hash; |
33dc9b12 | 4753 | int ret; |
f45948e8 | 4754 | |
41c52c0d | 4755 | if (unlikely(ftrace_disabled)) |
33dc9b12 | 4756 | return -ENODEV; |
41c52c0d | 4757 | |
33b7f99c | 4758 | mutex_lock(&ops->func_hash->regex_lock); |
3f2367ba | 4759 | |
f45948e8 | 4760 | if (enable) |
33b7f99c | 4761 | orig_hash = &ops->func_hash->filter_hash; |
f45948e8 | 4762 | else |
33b7f99c | 4763 | orig_hash = &ops->func_hash->notrace_hash; |
33dc9b12 | 4764 | |
b972cc58 WN |
4765 | if (reset) |
4766 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); | |
4767 | else | |
4768 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
4769 | ||
3f2367ba MH |
4770 | if (!hash) { |
4771 | ret = -ENOMEM; | |
4772 | goto out_regex_unlock; | |
4773 | } | |
f45948e8 | 4774 | |
ac483c44 JO |
4775 | if (buf && !ftrace_match_records(hash, buf, len)) { |
4776 | ret = -EINVAL; | |
4777 | goto out_regex_unlock; | |
4778 | } | |
647664ea MH |
4779 | if (ip) { |
4780 | ret = ftrace_match_addr(hash, ip, remove); | |
4781 | if (ret < 0) | |
4782 | goto out_regex_unlock; | |
4783 | } | |
33dc9b12 SR |
4784 | |
4785 | mutex_lock(&ftrace_lock); | |
e16b35dd | 4786 | ret = ftrace_hash_move_and_update_ops(ops, orig_hash, hash, enable); |
33dc9b12 SR |
4787 | mutex_unlock(&ftrace_lock); |
4788 | ||
ac483c44 | 4789 | out_regex_unlock: |
33b7f99c | 4790 | mutex_unlock(&ops->func_hash->regex_lock); |
33dc9b12 SR |
4791 | |
4792 | free_ftrace_hash(hash); | |
4793 | return ret; | |
41c52c0d SR |
4794 | } |
4795 | ||
647664ea MH |
4796 | static int |
4797 | ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove, | |
4798 | int reset, int enable) | |
4799 | { | |
9efb85c5 | 4800 | return ftrace_set_hash(ops, NULL, 0, ip, remove, reset, enable); |
647664ea MH |
4801 | } |
4802 | ||
4803 | /** | |
4804 | * ftrace_set_filter_ip - set a function to filter on in ftrace by address | |
4805 | * @ops - the ops to set the filter with | |
4806 | * @ip - the address to add to or remove from the filter. | |
4807 | * @remove - non zero to remove the ip from the filter | |
4808 | * @reset - non zero to reset all filters before applying this filter. | |
4809 | * | |
4810 | * Filters denote which functions should be enabled when tracing is enabled | |
4811 | * If @ip is NULL, it failes to update filter. | |
4812 | */ | |
4813 | int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, | |
4814 | int remove, int reset) | |
4815 | { | |
f04f24fb | 4816 | ftrace_ops_init(ops); |
647664ea MH |
4817 | return ftrace_set_addr(ops, ip, remove, reset, 1); |
4818 | } | |
4819 | EXPORT_SYMBOL_GPL(ftrace_set_filter_ip); | |
4820 | ||
d032ae89 JF |
4821 | /** |
4822 | * ftrace_ops_set_global_filter - setup ops to use global filters | |
4823 | * @ops - the ops which will use the global filters | |
4824 | * | |
4825 | * ftrace users who need global function trace filtering should call this. | |
4826 | * It can set the global filter only if ops were not initialized before. | |
4827 | */ | |
4828 | void ftrace_ops_set_global_filter(struct ftrace_ops *ops) | |
4829 | { | |
4830 | if (ops->flags & FTRACE_OPS_FL_INITIALIZED) | |
4831 | return; | |
4832 | ||
4833 | ftrace_ops_init(ops); | |
4834 | ops->func_hash = &global_ops.local_hash; | |
4835 | } | |
4836 | EXPORT_SYMBOL_GPL(ftrace_ops_set_global_filter); | |
4837 | ||
647664ea MH |
4838 | static int |
4839 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, | |
4840 | int reset, int enable) | |
4841 | { | |
4842 | return ftrace_set_hash(ops, buf, len, 0, 0, reset, enable); | |
4843 | } | |
4844 | ||
77a2b37d SR |
4845 | /** |
4846 | * ftrace_set_filter - set a function to filter on in ftrace | |
936e074b SR |
4847 | * @ops - the ops to set the filter with |
4848 | * @buf - the string that holds the function filter text. | |
4849 | * @len - the length of the string. | |
4850 | * @reset - non zero to reset all filters before applying this filter. | |
4851 | * | |
4852 | * Filters denote which functions should be enabled when tracing is enabled. | |
4853 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
4854 | */ | |
ac483c44 | 4855 | int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
4856 | int len, int reset) |
4857 | { | |
f04f24fb | 4858 | ftrace_ops_init(ops); |
ac483c44 | 4859 | return ftrace_set_regex(ops, buf, len, reset, 1); |
936e074b SR |
4860 | } |
4861 | EXPORT_SYMBOL_GPL(ftrace_set_filter); | |
4862 | ||
4863 | /** | |
4864 | * ftrace_set_notrace - set a function to not trace in ftrace | |
4865 | * @ops - the ops to set the notrace filter with | |
4866 | * @buf - the string that holds the function notrace text. | |
4867 | * @len - the length of the string. | |
4868 | * @reset - non zero to reset all filters before applying this filter. | |
4869 | * | |
4870 | * Notrace Filters denote which functions should not be enabled when tracing | |
4871 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
4872 | * for tracing. | |
4873 | */ | |
ac483c44 | 4874 | int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
4875 | int len, int reset) |
4876 | { | |
f04f24fb | 4877 | ftrace_ops_init(ops); |
ac483c44 | 4878 | return ftrace_set_regex(ops, buf, len, reset, 0); |
936e074b SR |
4879 | } |
4880 | EXPORT_SYMBOL_GPL(ftrace_set_notrace); | |
4881 | /** | |
8d1b065d | 4882 | * ftrace_set_global_filter - set a function to filter on with global tracers |
77a2b37d SR |
4883 | * @buf - the string that holds the function filter text. |
4884 | * @len - the length of the string. | |
4885 | * @reset - non zero to reset all filters before applying this filter. | |
4886 | * | |
4887 | * Filters denote which functions should be enabled when tracing is enabled. | |
4888 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
4889 | */ | |
936e074b | 4890 | void ftrace_set_global_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 4891 | { |
f45948e8 | 4892 | ftrace_set_regex(&global_ops, buf, len, reset, 1); |
41c52c0d | 4893 | } |
936e074b | 4894 | EXPORT_SYMBOL_GPL(ftrace_set_global_filter); |
4eebcc81 | 4895 | |
41c52c0d | 4896 | /** |
8d1b065d | 4897 | * ftrace_set_global_notrace - set a function to not trace with global tracers |
41c52c0d SR |
4898 | * @buf - the string that holds the function notrace text. |
4899 | * @len - the length of the string. | |
4900 | * @reset - non zero to reset all filters before applying this filter. | |
4901 | * | |
4902 | * Notrace Filters denote which functions should not be enabled when tracing | |
4903 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
4904 | * for tracing. | |
4905 | */ | |
936e074b | 4906 | void ftrace_set_global_notrace(unsigned char *buf, int len, int reset) |
41c52c0d | 4907 | { |
f45948e8 | 4908 | ftrace_set_regex(&global_ops, buf, len, reset, 0); |
77a2b37d | 4909 | } |
936e074b | 4910 | EXPORT_SYMBOL_GPL(ftrace_set_global_notrace); |
77a2b37d | 4911 | |
2af15d6a SR |
4912 | /* |
4913 | * command line interface to allow users to set filters on boot up. | |
4914 | */ | |
4915 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE | |
4916 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; | |
4917 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; | |
4918 | ||
f1ed7c74 SRRH |
4919 | /* Used by function selftest to not test if filter is set */ |
4920 | bool ftrace_filter_param __initdata; | |
4921 | ||
2af15d6a SR |
4922 | static int __init set_ftrace_notrace(char *str) |
4923 | { | |
f1ed7c74 | 4924 | ftrace_filter_param = true; |
75761cc1 | 4925 | strlcpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
4926 | return 1; |
4927 | } | |
4928 | __setup("ftrace_notrace=", set_ftrace_notrace); | |
4929 | ||
4930 | static int __init set_ftrace_filter(char *str) | |
4931 | { | |
f1ed7c74 | 4932 | ftrace_filter_param = true; |
75761cc1 | 4933 | strlcpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
4934 | return 1; |
4935 | } | |
4936 | __setup("ftrace_filter=", set_ftrace_filter); | |
4937 | ||
369bc18f | 4938 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
f6060f46 | 4939 | static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; |
0d7d9a16 | 4940 | static char ftrace_graph_notrace_buf[FTRACE_FILTER_SIZE] __initdata; |
b9b0c831 | 4941 | static int ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer); |
801c29fd | 4942 | |
369bc18f SA |
4943 | static int __init set_graph_function(char *str) |
4944 | { | |
06f43d66 | 4945 | strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); |
369bc18f SA |
4946 | return 1; |
4947 | } | |
4948 | __setup("ftrace_graph_filter=", set_graph_function); | |
4949 | ||
0d7d9a16 NK |
4950 | static int __init set_graph_notrace_function(char *str) |
4951 | { | |
4952 | strlcpy(ftrace_graph_notrace_buf, str, FTRACE_FILTER_SIZE); | |
4953 | return 1; | |
4954 | } | |
4955 | __setup("ftrace_graph_notrace=", set_graph_notrace_function); | |
4956 | ||
65a50c65 TB |
4957 | static int __init set_graph_max_depth_function(char *str) |
4958 | { | |
4959 | if (!str) | |
4960 | return 0; | |
4961 | fgraph_max_depth = simple_strtoul(str, NULL, 0); | |
4962 | return 1; | |
4963 | } | |
4964 | __setup("ftrace_graph_max_depth=", set_graph_max_depth_function); | |
0d7d9a16 NK |
4965 | |
4966 | static void __init set_ftrace_early_graph(char *buf, int enable) | |
369bc18f SA |
4967 | { |
4968 | int ret; | |
4969 | char *func; | |
b9b0c831 | 4970 | struct ftrace_hash *hash; |
0d7d9a16 | 4971 | |
92ad18ec SRV |
4972 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); |
4973 | if (WARN_ON(!hash)) | |
4974 | return; | |
369bc18f SA |
4975 | |
4976 | while (buf) { | |
4977 | func = strsep(&buf, ","); | |
4978 | /* we allow only one expression at a time */ | |
b9b0c831 | 4979 | ret = ftrace_graph_set_hash(hash, func); |
369bc18f SA |
4980 | if (ret) |
4981 | printk(KERN_DEBUG "ftrace: function %s not " | |
4982 | "traceable\n", func); | |
4983 | } | |
92ad18ec SRV |
4984 | |
4985 | if (enable) | |
4986 | ftrace_graph_hash = hash; | |
4987 | else | |
4988 | ftrace_graph_notrace_hash = hash; | |
369bc18f SA |
4989 | } |
4990 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
4991 | ||
2a85a37f SR |
4992 | void __init |
4993 | ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable) | |
2af15d6a SR |
4994 | { |
4995 | char *func; | |
4996 | ||
f04f24fb MH |
4997 | ftrace_ops_init(ops); |
4998 | ||
2af15d6a SR |
4999 | while (buf) { |
5000 | func = strsep(&buf, ","); | |
f45948e8 | 5001 | ftrace_set_regex(ops, func, strlen(func), 0, enable); |
2af15d6a SR |
5002 | } |
5003 | } | |
5004 | ||
5005 | static void __init set_ftrace_early_filters(void) | |
5006 | { | |
5007 | if (ftrace_filter_buf[0]) | |
2a85a37f | 5008 | ftrace_set_early_filter(&global_ops, ftrace_filter_buf, 1); |
2af15d6a | 5009 | if (ftrace_notrace_buf[0]) |
2a85a37f | 5010 | ftrace_set_early_filter(&global_ops, ftrace_notrace_buf, 0); |
369bc18f SA |
5011 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5012 | if (ftrace_graph_buf[0]) | |
0d7d9a16 NK |
5013 | set_ftrace_early_graph(ftrace_graph_buf, 1); |
5014 | if (ftrace_graph_notrace_buf[0]) | |
5015 | set_ftrace_early_graph(ftrace_graph_notrace_buf, 0); | |
369bc18f | 5016 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
2af15d6a SR |
5017 | } |
5018 | ||
fc13cb0c | 5019 | int ftrace_regex_release(struct inode *inode, struct file *file) |
5072c59f SR |
5020 | { |
5021 | struct seq_file *m = (struct seq_file *)file->private_data; | |
5022 | struct ftrace_iterator *iter; | |
33dc9b12 | 5023 | struct ftrace_hash **orig_hash; |
689fd8b6 | 5024 | struct trace_parser *parser; |
ed926f9b | 5025 | int filter_hash; |
33dc9b12 | 5026 | int ret; |
5072c59f | 5027 | |
5072c59f SR |
5028 | if (file->f_mode & FMODE_READ) { |
5029 | iter = m->private; | |
5072c59f SR |
5030 | seq_release(inode, file); |
5031 | } else | |
5032 | iter = file->private_data; | |
5033 | ||
689fd8b6 | 5034 | parser = &iter->parser; |
5035 | if (trace_parser_loaded(parser)) { | |
1cf41dd7 | 5036 | ftrace_match_records(iter->hash, parser->buffer, parser->idx); |
5072c59f SR |
5037 | } |
5038 | ||
689fd8b6 | 5039 | trace_parser_put(parser); |
689fd8b6 | 5040 | |
33b7f99c | 5041 | mutex_lock(&iter->ops->func_hash->regex_lock); |
3f2367ba | 5042 | |
058e297d | 5043 | if (file->f_mode & FMODE_WRITE) { |
ed926f9b SR |
5044 | filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); |
5045 | ||
8c08f0d5 | 5046 | if (filter_hash) { |
33b7f99c | 5047 | orig_hash = &iter->ops->func_hash->filter_hash; |
69d71879 | 5048 | if (iter->tr && !list_empty(&iter->tr->mod_trace)) |
8c08f0d5 SRV |
5049 | iter->hash->flags |= FTRACE_HASH_FL_MOD; |
5050 | } else | |
33b7f99c | 5051 | orig_hash = &iter->ops->func_hash->notrace_hash; |
33dc9b12 | 5052 | |
058e297d | 5053 | mutex_lock(&ftrace_lock); |
e16b35dd SRV |
5054 | ret = ftrace_hash_move_and_update_ops(iter->ops, orig_hash, |
5055 | iter->hash, filter_hash); | |
058e297d | 5056 | mutex_unlock(&ftrace_lock); |
c20489da SRV |
5057 | } else { |
5058 | /* For read only, the hash is the ops hash */ | |
5059 | iter->hash = NULL; | |
058e297d | 5060 | } |
3f2367ba | 5061 | |
33b7f99c | 5062 | mutex_unlock(&iter->ops->func_hash->regex_lock); |
33dc9b12 | 5063 | free_ftrace_hash(iter->hash); |
9ef16693 SRV |
5064 | if (iter->tr) |
5065 | trace_array_put(iter->tr); | |
33dc9b12 | 5066 | kfree(iter); |
058e297d | 5067 | |
5072c59f SR |
5068 | return 0; |
5069 | } | |
5070 | ||
5e2336a0 | 5071 | static const struct file_operations ftrace_avail_fops = { |
5072c59f SR |
5072 | .open = ftrace_avail_open, |
5073 | .read = seq_read, | |
5074 | .llseek = seq_lseek, | |
3be04b47 | 5075 | .release = seq_release_private, |
5072c59f SR |
5076 | }; |
5077 | ||
647bcd03 SR |
5078 | static const struct file_operations ftrace_enabled_fops = { |
5079 | .open = ftrace_enabled_open, | |
5080 | .read = seq_read, | |
5081 | .llseek = seq_lseek, | |
5082 | .release = seq_release_private, | |
5083 | }; | |
5084 | ||
5e2336a0 | 5085 | static const struct file_operations ftrace_filter_fops = { |
5072c59f | 5086 | .open = ftrace_filter_open, |
850a80cf | 5087 | .read = seq_read, |
5072c59f | 5088 | .write = ftrace_filter_write, |
098c879e | 5089 | .llseek = tracing_lseek, |
1cf41dd7 | 5090 | .release = ftrace_regex_release, |
5072c59f SR |
5091 | }; |
5092 | ||
5e2336a0 | 5093 | static const struct file_operations ftrace_notrace_fops = { |
41c52c0d | 5094 | .open = ftrace_notrace_open, |
850a80cf | 5095 | .read = seq_read, |
41c52c0d | 5096 | .write = ftrace_notrace_write, |
098c879e | 5097 | .llseek = tracing_lseek, |
1cf41dd7 | 5098 | .release = ftrace_regex_release, |
41c52c0d SR |
5099 | }; |
5100 | ||
ea4e2bc4 SR |
5101 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5102 | ||
5103 | static DEFINE_MUTEX(graph_lock); | |
5104 | ||
b9b0c831 NK |
5105 | struct ftrace_hash *ftrace_graph_hash = EMPTY_HASH; |
5106 | struct ftrace_hash *ftrace_graph_notrace_hash = EMPTY_HASH; | |
5107 | ||
5108 | enum graph_filter_type { | |
5109 | GRAPH_FILTER_NOTRACE = 0, | |
5110 | GRAPH_FILTER_FUNCTION, | |
5111 | }; | |
ea4e2bc4 | 5112 | |
555fc781 SRV |
5113 | #define FTRACE_GRAPH_EMPTY ((void *)1) |
5114 | ||
faf982a6 | 5115 | struct ftrace_graph_data { |
e704eff3 SRV |
5116 | struct ftrace_hash *hash; |
5117 | struct ftrace_func_entry *entry; | |
5118 | int idx; /* for hash table iteration */ | |
5119 | enum graph_filter_type type; | |
5120 | struct ftrace_hash *new_hash; | |
5121 | const struct seq_operations *seq_ops; | |
5122 | struct trace_parser parser; | |
faf982a6 NK |
5123 | }; |
5124 | ||
ea4e2bc4 | 5125 | static void * |
85951842 | 5126 | __g_next(struct seq_file *m, loff_t *pos) |
ea4e2bc4 | 5127 | { |
faf982a6 | 5128 | struct ftrace_graph_data *fgd = m->private; |
b9b0c831 NK |
5129 | struct ftrace_func_entry *entry = fgd->entry; |
5130 | struct hlist_head *head; | |
5131 | int i, idx = fgd->idx; | |
faf982a6 | 5132 | |
b9b0c831 | 5133 | if (*pos >= fgd->hash->count) |
ea4e2bc4 | 5134 | return NULL; |
b9b0c831 NK |
5135 | |
5136 | if (entry) { | |
5137 | hlist_for_each_entry_continue(entry, hlist) { | |
5138 | fgd->entry = entry; | |
5139 | return entry; | |
5140 | } | |
5141 | ||
5142 | idx++; | |
5143 | } | |
5144 | ||
5145 | for (i = idx; i < 1 << fgd->hash->size_bits; i++) { | |
5146 | head = &fgd->hash->buckets[i]; | |
5147 | hlist_for_each_entry(entry, head, hlist) { | |
5148 | fgd->entry = entry; | |
5149 | fgd->idx = i; | |
5150 | return entry; | |
5151 | } | |
5152 | } | |
5153 | return NULL; | |
85951842 | 5154 | } |
ea4e2bc4 | 5155 | |
85951842 LZ |
5156 | static void * |
5157 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
5158 | { | |
5159 | (*pos)++; | |
5160 | return __g_next(m, pos); | |
ea4e2bc4 SR |
5161 | } |
5162 | ||
5163 | static void *g_start(struct seq_file *m, loff_t *pos) | |
5164 | { | |
faf982a6 NK |
5165 | struct ftrace_graph_data *fgd = m->private; |
5166 | ||
ea4e2bc4 SR |
5167 | mutex_lock(&graph_lock); |
5168 | ||
649b988b SRV |
5169 | if (fgd->type == GRAPH_FILTER_FUNCTION) |
5170 | fgd->hash = rcu_dereference_protected(ftrace_graph_hash, | |
5171 | lockdep_is_held(&graph_lock)); | |
5172 | else | |
5173 | fgd->hash = rcu_dereference_protected(ftrace_graph_notrace_hash, | |
5174 | lockdep_is_held(&graph_lock)); | |
5175 | ||
f9349a8f | 5176 | /* Nothing, tell g_show to print all functions are enabled */ |
b9b0c831 | 5177 | if (ftrace_hash_empty(fgd->hash) && !*pos) |
555fc781 | 5178 | return FTRACE_GRAPH_EMPTY; |
f9349a8f | 5179 | |
b9b0c831 NK |
5180 | fgd->idx = 0; |
5181 | fgd->entry = NULL; | |
85951842 | 5182 | return __g_next(m, pos); |
ea4e2bc4 SR |
5183 | } |
5184 | ||
5185 | static void g_stop(struct seq_file *m, void *p) | |
5186 | { | |
5187 | mutex_unlock(&graph_lock); | |
5188 | } | |
5189 | ||
5190 | static int g_show(struct seq_file *m, void *v) | |
5191 | { | |
b9b0c831 | 5192 | struct ftrace_func_entry *entry = v; |
ea4e2bc4 | 5193 | |
b9b0c831 | 5194 | if (!entry) |
ea4e2bc4 SR |
5195 | return 0; |
5196 | ||
555fc781 | 5197 | if (entry == FTRACE_GRAPH_EMPTY) { |
280d1429 NK |
5198 | struct ftrace_graph_data *fgd = m->private; |
5199 | ||
b9b0c831 | 5200 | if (fgd->type == GRAPH_FILTER_FUNCTION) |
fa6f0cc7 | 5201 | seq_puts(m, "#### all functions enabled ####\n"); |
280d1429 | 5202 | else |
fa6f0cc7 | 5203 | seq_puts(m, "#### no functions disabled ####\n"); |
f9349a8f FW |
5204 | return 0; |
5205 | } | |
5206 | ||
b9b0c831 | 5207 | seq_printf(m, "%ps\n", (void *)entry->ip); |
ea4e2bc4 SR |
5208 | |
5209 | return 0; | |
5210 | } | |
5211 | ||
88e9d34c | 5212 | static const struct seq_operations ftrace_graph_seq_ops = { |
ea4e2bc4 SR |
5213 | .start = g_start, |
5214 | .next = g_next, | |
5215 | .stop = g_stop, | |
5216 | .show = g_show, | |
5217 | }; | |
5218 | ||
5219 | static int | |
faf982a6 NK |
5220 | __ftrace_graph_open(struct inode *inode, struct file *file, |
5221 | struct ftrace_graph_data *fgd) | |
ea4e2bc4 | 5222 | { |
17911ff3 | 5223 | int ret; |
b9b0c831 | 5224 | struct ftrace_hash *new_hash = NULL; |
ea4e2bc4 | 5225 | |
17911ff3 SRV |
5226 | ret = security_locked_down(LOCKDOWN_TRACEFS); |
5227 | if (ret) | |
5228 | return ret; | |
5229 | ||
b9b0c831 NK |
5230 | if (file->f_mode & FMODE_WRITE) { |
5231 | const int size_bits = FTRACE_HASH_DEFAULT_BITS; | |
5232 | ||
e704eff3 SRV |
5233 | if (trace_parser_get_init(&fgd->parser, FTRACE_BUFF_MAX)) |
5234 | return -ENOMEM; | |
5235 | ||
b9b0c831 NK |
5236 | if (file->f_flags & O_TRUNC) |
5237 | new_hash = alloc_ftrace_hash(size_bits); | |
5238 | else | |
5239 | new_hash = alloc_and_copy_ftrace_hash(size_bits, | |
5240 | fgd->hash); | |
5241 | if (!new_hash) { | |
5242 | ret = -ENOMEM; | |
5243 | goto out; | |
5244 | } | |
ea4e2bc4 SR |
5245 | } |
5246 | ||
faf982a6 | 5247 | if (file->f_mode & FMODE_READ) { |
b9b0c831 | 5248 | ret = seq_open(file, &ftrace_graph_seq_ops); |
faf982a6 NK |
5249 | if (!ret) { |
5250 | struct seq_file *m = file->private_data; | |
5251 | m->private = fgd; | |
b9b0c831 NK |
5252 | } else { |
5253 | /* Failed */ | |
5254 | free_ftrace_hash(new_hash); | |
5255 | new_hash = NULL; | |
faf982a6 NK |
5256 | } |
5257 | } else | |
5258 | file->private_data = fgd; | |
ea4e2bc4 | 5259 | |
b9b0c831 | 5260 | out: |
e704eff3 SRV |
5261 | if (ret < 0 && file->f_mode & FMODE_WRITE) |
5262 | trace_parser_put(&fgd->parser); | |
5263 | ||
b9b0c831 | 5264 | fgd->new_hash = new_hash; |
649b988b SRV |
5265 | |
5266 | /* | |
5267 | * All uses of fgd->hash must be taken with the graph_lock | |
5268 | * held. The graph_lock is going to be released, so force | |
5269 | * fgd->hash to be reinitialized when it is taken again. | |
5270 | */ | |
5271 | fgd->hash = NULL; | |
5272 | ||
ea4e2bc4 SR |
5273 | return ret; |
5274 | } | |
5275 | ||
faf982a6 NK |
5276 | static int |
5277 | ftrace_graph_open(struct inode *inode, struct file *file) | |
5278 | { | |
5279 | struct ftrace_graph_data *fgd; | |
b9b0c831 | 5280 | int ret; |
faf982a6 NK |
5281 | |
5282 | if (unlikely(ftrace_disabled)) | |
5283 | return -ENODEV; | |
5284 | ||
5285 | fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); | |
5286 | if (fgd == NULL) | |
5287 | return -ENOMEM; | |
5288 | ||
b9b0c831 NK |
5289 | mutex_lock(&graph_lock); |
5290 | ||
649b988b SRV |
5291 | fgd->hash = rcu_dereference_protected(ftrace_graph_hash, |
5292 | lockdep_is_held(&graph_lock)); | |
b9b0c831 | 5293 | fgd->type = GRAPH_FILTER_FUNCTION; |
faf982a6 NK |
5294 | fgd->seq_ops = &ftrace_graph_seq_ops; |
5295 | ||
b9b0c831 NK |
5296 | ret = __ftrace_graph_open(inode, file, fgd); |
5297 | if (ret < 0) | |
5298 | kfree(fgd); | |
5299 | ||
5300 | mutex_unlock(&graph_lock); | |
5301 | return ret; | |
faf982a6 NK |
5302 | } |
5303 | ||
29ad23b0 NK |
5304 | static int |
5305 | ftrace_graph_notrace_open(struct inode *inode, struct file *file) | |
5306 | { | |
5307 | struct ftrace_graph_data *fgd; | |
b9b0c831 | 5308 | int ret; |
29ad23b0 NK |
5309 | |
5310 | if (unlikely(ftrace_disabled)) | |
5311 | return -ENODEV; | |
5312 | ||
5313 | fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); | |
5314 | if (fgd == NULL) | |
5315 | return -ENOMEM; | |
5316 | ||
b9b0c831 NK |
5317 | mutex_lock(&graph_lock); |
5318 | ||
649b988b SRV |
5319 | fgd->hash = rcu_dereference_protected(ftrace_graph_notrace_hash, |
5320 | lockdep_is_held(&graph_lock)); | |
b9b0c831 | 5321 | fgd->type = GRAPH_FILTER_NOTRACE; |
29ad23b0 NK |
5322 | fgd->seq_ops = &ftrace_graph_seq_ops; |
5323 | ||
b9b0c831 NK |
5324 | ret = __ftrace_graph_open(inode, file, fgd); |
5325 | if (ret < 0) | |
5326 | kfree(fgd); | |
5327 | ||
5328 | mutex_unlock(&graph_lock); | |
5329 | return ret; | |
29ad23b0 NK |
5330 | } |
5331 | ||
87827111 LZ |
5332 | static int |
5333 | ftrace_graph_release(struct inode *inode, struct file *file) | |
5334 | { | |
b9b0c831 | 5335 | struct ftrace_graph_data *fgd; |
e704eff3 SRV |
5336 | struct ftrace_hash *old_hash, *new_hash; |
5337 | struct trace_parser *parser; | |
5338 | int ret = 0; | |
b9b0c831 | 5339 | |
faf982a6 NK |
5340 | if (file->f_mode & FMODE_READ) { |
5341 | struct seq_file *m = file->private_data; | |
5342 | ||
b9b0c831 | 5343 | fgd = m->private; |
87827111 | 5344 | seq_release(inode, file); |
faf982a6 | 5345 | } else { |
b9b0c831 | 5346 | fgd = file->private_data; |
faf982a6 NK |
5347 | } |
5348 | ||
e704eff3 SRV |
5349 | |
5350 | if (file->f_mode & FMODE_WRITE) { | |
5351 | ||
5352 | parser = &fgd->parser; | |
5353 | ||
5354 | if (trace_parser_loaded((parser))) { | |
e704eff3 SRV |
5355 | ret = ftrace_graph_set_hash(fgd->new_hash, |
5356 | parser->buffer); | |
5357 | } | |
5358 | ||
5359 | trace_parser_put(parser); | |
5360 | ||
5361 | new_hash = __ftrace_hash_move(fgd->new_hash); | |
5362 | if (!new_hash) { | |
5363 | ret = -ENOMEM; | |
5364 | goto out; | |
5365 | } | |
5366 | ||
5367 | mutex_lock(&graph_lock); | |
5368 | ||
5369 | if (fgd->type == GRAPH_FILTER_FUNCTION) { | |
5370 | old_hash = rcu_dereference_protected(ftrace_graph_hash, | |
5371 | lockdep_is_held(&graph_lock)); | |
5372 | rcu_assign_pointer(ftrace_graph_hash, new_hash); | |
5373 | } else { | |
5374 | old_hash = rcu_dereference_protected(ftrace_graph_notrace_hash, | |
5375 | lockdep_is_held(&graph_lock)); | |
5376 | rcu_assign_pointer(ftrace_graph_notrace_hash, new_hash); | |
5377 | } | |
5378 | ||
5379 | mutex_unlock(&graph_lock); | |
5380 | ||
5381 | /* Wait till all users are no longer using the old hash */ | |
74401729 | 5382 | synchronize_rcu(); |
e704eff3 SRV |
5383 | |
5384 | free_ftrace_hash(old_hash); | |
5385 | } | |
5386 | ||
5387 | out: | |
f9797c2f | 5388 | free_ftrace_hash(fgd->new_hash); |
b9b0c831 NK |
5389 | kfree(fgd); |
5390 | ||
e704eff3 | 5391 | return ret; |
87827111 LZ |
5392 | } |
5393 | ||
ea4e2bc4 | 5394 | static int |
b9b0c831 | 5395 | ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer) |
ea4e2bc4 | 5396 | { |
3ba00929 | 5397 | struct ftrace_glob func_g; |
ea4e2bc4 SR |
5398 | struct dyn_ftrace *rec; |
5399 | struct ftrace_page *pg; | |
b9b0c831 | 5400 | struct ftrace_func_entry *entry; |
c7c6b1fe | 5401 | int fail = 1; |
3ba00929 | 5402 | int not; |
ea4e2bc4 | 5403 | |
f9349a8f | 5404 | /* decode regex */ |
3ba00929 DS |
5405 | func_g.type = filter_parse_regex(buffer, strlen(buffer), |
5406 | &func_g.search, ¬); | |
f9349a8f | 5407 | |
3ba00929 | 5408 | func_g.len = strlen(func_g.search); |
f9349a8f | 5409 | |
52baf119 | 5410 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
5411 | |
5412 | if (unlikely(ftrace_disabled)) { | |
5413 | mutex_unlock(&ftrace_lock); | |
5414 | return -ENODEV; | |
5415 | } | |
5416 | ||
265c831c SR |
5417 | do_for_each_ftrace_rec(pg, rec) { |
5418 | ||
546fece4 SRRH |
5419 | if (rec->flags & FTRACE_FL_DISABLED) |
5420 | continue; | |
5421 | ||
0b507e1e | 5422 | if (ftrace_match_record(rec, &func_g, NULL, 0)) { |
b9b0c831 | 5423 | entry = ftrace_lookup_ip(hash, rec->ip); |
c7c6b1fe LZ |
5424 | |
5425 | if (!not) { | |
5426 | fail = 0; | |
b9b0c831 NK |
5427 | |
5428 | if (entry) | |
5429 | continue; | |
5430 | if (add_hash_entry(hash, rec->ip) < 0) | |
5431 | goto out; | |
c7c6b1fe | 5432 | } else { |
b9b0c831 NK |
5433 | if (entry) { |
5434 | free_hash_entry(hash, entry); | |
c7c6b1fe LZ |
5435 | fail = 0; |
5436 | } | |
5437 | } | |
ea4e2bc4 | 5438 | } |
265c831c | 5439 | } while_for_each_ftrace_rec(); |
c7c6b1fe | 5440 | out: |
52baf119 | 5441 | mutex_unlock(&ftrace_lock); |
ea4e2bc4 | 5442 | |
c7c6b1fe LZ |
5443 | if (fail) |
5444 | return -EINVAL; | |
5445 | ||
c7c6b1fe | 5446 | return 0; |
ea4e2bc4 SR |
5447 | } |
5448 | ||
5449 | static ssize_t | |
5450 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
5451 | size_t cnt, loff_t *ppos) | |
5452 | { | |
6a10108b | 5453 | ssize_t read, ret = 0; |
faf982a6 | 5454 | struct ftrace_graph_data *fgd = file->private_data; |
e704eff3 | 5455 | struct trace_parser *parser; |
ea4e2bc4 | 5456 | |
c7c6b1fe | 5457 | if (!cnt) |
ea4e2bc4 SR |
5458 | return 0; |
5459 | ||
ae98d27a SRV |
5460 | /* Read mode uses seq functions */ |
5461 | if (file->f_mode & FMODE_READ) { | |
5462 | struct seq_file *m = file->private_data; | |
5463 | fgd = m->private; | |
5464 | } | |
5465 | ||
e704eff3 | 5466 | parser = &fgd->parser; |
ea4e2bc4 | 5467 | |
e704eff3 | 5468 | read = trace_get_user(parser, ubuf, cnt, ppos); |
689fd8b6 | 5469 | |
e704eff3 SRV |
5470 | if (read >= 0 && trace_parser_loaded(parser) && |
5471 | !trace_parser_cont(parser)) { | |
6a10108b | 5472 | |
b9b0c831 | 5473 | ret = ftrace_graph_set_hash(fgd->new_hash, |
e704eff3 SRV |
5474 | parser->buffer); |
5475 | trace_parser_clear(parser); | |
ea4e2bc4 | 5476 | } |
ea4e2bc4 | 5477 | |
6a10108b NK |
5478 | if (!ret) |
5479 | ret = read; | |
1eb90f13 | 5480 | |
ea4e2bc4 SR |
5481 | return ret; |
5482 | } | |
5483 | ||
5484 | static const struct file_operations ftrace_graph_fops = { | |
87827111 LZ |
5485 | .open = ftrace_graph_open, |
5486 | .read = seq_read, | |
5487 | .write = ftrace_graph_write, | |
098c879e | 5488 | .llseek = tracing_lseek, |
87827111 | 5489 | .release = ftrace_graph_release, |
ea4e2bc4 | 5490 | }; |
29ad23b0 NK |
5491 | |
5492 | static const struct file_operations ftrace_graph_notrace_fops = { | |
5493 | .open = ftrace_graph_notrace_open, | |
5494 | .read = seq_read, | |
5495 | .write = ftrace_graph_write, | |
098c879e | 5496 | .llseek = tracing_lseek, |
29ad23b0 NK |
5497 | .release = ftrace_graph_release, |
5498 | }; | |
ea4e2bc4 SR |
5499 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
5500 | ||
591dffda SRRH |
5501 | void ftrace_create_filter_files(struct ftrace_ops *ops, |
5502 | struct dentry *parent) | |
5503 | { | |
5504 | ||
5505 | trace_create_file("set_ftrace_filter", 0644, parent, | |
5506 | ops, &ftrace_filter_fops); | |
5507 | ||
5508 | trace_create_file("set_ftrace_notrace", 0644, parent, | |
5509 | ops, &ftrace_notrace_fops); | |
5510 | } | |
5511 | ||
5512 | /* | |
5513 | * The name "destroy_filter_files" is really a misnomer. Although | |
9efb85c5 | 5514 | * in the future, it may actually delete the files, but this is |
591dffda SRRH |
5515 | * really intended to make sure the ops passed in are disabled |
5516 | * and that when this function returns, the caller is free to | |
5517 | * free the ops. | |
5518 | * | |
5519 | * The "destroy" name is only to match the "create" name that this | |
5520 | * should be paired with. | |
5521 | */ | |
5522 | void ftrace_destroy_filter_files(struct ftrace_ops *ops) | |
5523 | { | |
5524 | mutex_lock(&ftrace_lock); | |
5525 | if (ops->flags & FTRACE_OPS_FL_ENABLED) | |
5526 | ftrace_shutdown(ops, 0); | |
5527 | ops->flags |= FTRACE_OPS_FL_DELETED; | |
2840f84f | 5528 | ftrace_free_filter(ops); |
591dffda SRRH |
5529 | mutex_unlock(&ftrace_lock); |
5530 | } | |
5531 | ||
8434dc93 | 5532 | static __init int ftrace_init_dyn_tracefs(struct dentry *d_tracer) |
5072c59f | 5533 | { |
5072c59f | 5534 | |
5452af66 FW |
5535 | trace_create_file("available_filter_functions", 0444, |
5536 | d_tracer, NULL, &ftrace_avail_fops); | |
5072c59f | 5537 | |
647bcd03 SR |
5538 | trace_create_file("enabled_functions", 0444, |
5539 | d_tracer, NULL, &ftrace_enabled_fops); | |
5540 | ||
591dffda | 5541 | ftrace_create_filter_files(&global_ops, d_tracer); |
ad90c0e3 | 5542 | |
ea4e2bc4 | 5543 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
1ce0500d | 5544 | trace_create_file("set_graph_function", 0644, d_tracer, |
ea4e2bc4 SR |
5545 | NULL, |
5546 | &ftrace_graph_fops); | |
1ce0500d | 5547 | trace_create_file("set_graph_notrace", 0644, d_tracer, |
29ad23b0 NK |
5548 | NULL, |
5549 | &ftrace_graph_notrace_fops); | |
ea4e2bc4 SR |
5550 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
5551 | ||
5072c59f SR |
5552 | return 0; |
5553 | } | |
5554 | ||
9fd49328 | 5555 | static int ftrace_cmp_ips(const void *a, const void *b) |
68950619 | 5556 | { |
9fd49328 SR |
5557 | const unsigned long *ipa = a; |
5558 | const unsigned long *ipb = b; | |
68950619 | 5559 | |
9fd49328 SR |
5560 | if (*ipa > *ipb) |
5561 | return 1; | |
5562 | if (*ipa < *ipb) | |
5563 | return -1; | |
5564 | return 0; | |
5565 | } | |
5566 | ||
5cb084bb | 5567 | static int ftrace_process_locs(struct module *mod, |
31e88909 | 5568 | unsigned long *start, |
68bf21aa SR |
5569 | unsigned long *end) |
5570 | { | |
706c81f8 | 5571 | struct ftrace_page *start_pg; |
a7900875 | 5572 | struct ftrace_page *pg; |
706c81f8 | 5573 | struct dyn_ftrace *rec; |
a7900875 | 5574 | unsigned long count; |
68bf21aa SR |
5575 | unsigned long *p; |
5576 | unsigned long addr; | |
4376cac6 | 5577 | unsigned long flags = 0; /* Shut up gcc */ |
a7900875 SR |
5578 | int ret = -ENOMEM; |
5579 | ||
5580 | count = end - start; | |
5581 | ||
5582 | if (!count) | |
5583 | return 0; | |
5584 | ||
9fd49328 | 5585 | sort(start, count, sizeof(*start), |
6db02903 | 5586 | ftrace_cmp_ips, NULL); |
9fd49328 | 5587 | |
706c81f8 SR |
5588 | start_pg = ftrace_allocate_pages(count); |
5589 | if (!start_pg) | |
a7900875 | 5590 | return -ENOMEM; |
68bf21aa | 5591 | |
e6ea44e9 | 5592 | mutex_lock(&ftrace_lock); |
a7900875 | 5593 | |
32082309 SR |
5594 | /* |
5595 | * Core and each module needs their own pages, as | |
5596 | * modules will free them when they are removed. | |
5597 | * Force a new page to be allocated for modules. | |
5598 | */ | |
a7900875 SR |
5599 | if (!mod) { |
5600 | WARN_ON(ftrace_pages || ftrace_pages_start); | |
5601 | /* First initialization */ | |
706c81f8 | 5602 | ftrace_pages = ftrace_pages_start = start_pg; |
a7900875 | 5603 | } else { |
32082309 | 5604 | if (!ftrace_pages) |
a7900875 | 5605 | goto out; |
32082309 | 5606 | |
a7900875 SR |
5607 | if (WARN_ON(ftrace_pages->next)) { |
5608 | /* Hmm, we have free pages? */ | |
5609 | while (ftrace_pages->next) | |
5610 | ftrace_pages = ftrace_pages->next; | |
32082309 | 5611 | } |
a7900875 | 5612 | |
706c81f8 | 5613 | ftrace_pages->next = start_pg; |
32082309 SR |
5614 | } |
5615 | ||
68bf21aa | 5616 | p = start; |
706c81f8 | 5617 | pg = start_pg; |
68bf21aa SR |
5618 | while (p < end) { |
5619 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
5620 | /* |
5621 | * Some architecture linkers will pad between | |
5622 | * the different mcount_loc sections of different | |
5623 | * object files to satisfy alignments. | |
5624 | * Skip any NULL pointers. | |
5625 | */ | |
5626 | if (!addr) | |
5627 | continue; | |
706c81f8 SR |
5628 | |
5629 | if (pg->index == pg->size) { | |
5630 | /* We should have allocated enough */ | |
5631 | if (WARN_ON(!pg->next)) | |
5632 | break; | |
5633 | pg = pg->next; | |
5634 | } | |
5635 | ||
5636 | rec = &pg->records[pg->index++]; | |
5637 | rec->ip = addr; | |
68bf21aa SR |
5638 | } |
5639 | ||
706c81f8 SR |
5640 | /* We should have used all pages */ |
5641 | WARN_ON(pg->next); | |
5642 | ||
5643 | /* Assign the last page to ftrace_pages */ | |
5644 | ftrace_pages = pg; | |
5645 | ||
a4f18ed1 | 5646 | /* |
4376cac6 SR |
5647 | * We only need to disable interrupts on start up |
5648 | * because we are modifying code that an interrupt | |
5649 | * may execute, and the modification is not atomic. | |
5650 | * But for modules, nothing runs the code we modify | |
5651 | * until we are finished with it, and there's no | |
5652 | * reason to cause large interrupt latencies while we do it. | |
a4f18ed1 | 5653 | */ |
4376cac6 SR |
5654 | if (!mod) |
5655 | local_irq_save(flags); | |
1dc43cf0 | 5656 | ftrace_update_code(mod, start_pg); |
4376cac6 SR |
5657 | if (!mod) |
5658 | local_irq_restore(flags); | |
a7900875 SR |
5659 | ret = 0; |
5660 | out: | |
e6ea44e9 | 5661 | mutex_unlock(&ftrace_lock); |
68bf21aa | 5662 | |
a7900875 | 5663 | return ret; |
68bf21aa SR |
5664 | } |
5665 | ||
aba4b5c2 SRV |
5666 | struct ftrace_mod_func { |
5667 | struct list_head list; | |
5668 | char *name; | |
5669 | unsigned long ip; | |
5670 | unsigned int size; | |
5671 | }; | |
5672 | ||
5673 | struct ftrace_mod_map { | |
6aa69784 | 5674 | struct rcu_head rcu; |
aba4b5c2 SRV |
5675 | struct list_head list; |
5676 | struct module *mod; | |
5677 | unsigned long start_addr; | |
5678 | unsigned long end_addr; | |
5679 | struct list_head funcs; | |
6171a031 | 5680 | unsigned int num_funcs; |
aba4b5c2 SRV |
5681 | }; |
5682 | ||
93eb677d | 5683 | #ifdef CONFIG_MODULES |
32082309 SR |
5684 | |
5685 | #define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next) | |
5686 | ||
6aa69784 SRV |
5687 | static LIST_HEAD(ftrace_mod_maps); |
5688 | ||
b7ffffbb SRRH |
5689 | static int referenced_filters(struct dyn_ftrace *rec) |
5690 | { | |
5691 | struct ftrace_ops *ops; | |
5692 | int cnt = 0; | |
5693 | ||
5694 | for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) { | |
5695 | if (ops_references_rec(ops, rec)) | |
5696 | cnt++; | |
5697 | } | |
5698 | ||
5699 | return cnt; | |
5700 | } | |
5701 | ||
2a5bfe47 SRV |
5702 | static void |
5703 | clear_mod_from_hash(struct ftrace_page *pg, struct ftrace_hash *hash) | |
5704 | { | |
5705 | struct ftrace_func_entry *entry; | |
5706 | struct dyn_ftrace *rec; | |
5707 | int i; | |
5708 | ||
5709 | if (ftrace_hash_empty(hash)) | |
5710 | return; | |
5711 | ||
5712 | for (i = 0; i < pg->index; i++) { | |
5713 | rec = &pg->records[i]; | |
5714 | entry = __ftrace_lookup_ip(hash, rec->ip); | |
5715 | /* | |
5716 | * Do not allow this rec to match again. | |
5717 | * Yeah, it may waste some memory, but will be removed | |
5718 | * if/when the hash is modified again. | |
5719 | */ | |
5720 | if (entry) | |
5721 | entry->ip = 0; | |
5722 | } | |
5723 | } | |
5724 | ||
5725 | /* Clear any records from hashs */ | |
5726 | static void clear_mod_from_hashes(struct ftrace_page *pg) | |
5727 | { | |
5728 | struct trace_array *tr; | |
5729 | ||
5730 | mutex_lock(&trace_types_lock); | |
5731 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
5732 | if (!tr->ops || !tr->ops->func_hash) | |
5733 | continue; | |
5734 | mutex_lock(&tr->ops->func_hash->regex_lock); | |
5735 | clear_mod_from_hash(pg, tr->ops->func_hash->filter_hash); | |
5736 | clear_mod_from_hash(pg, tr->ops->func_hash->notrace_hash); | |
5737 | mutex_unlock(&tr->ops->func_hash->regex_lock); | |
5738 | } | |
5739 | mutex_unlock(&trace_types_lock); | |
5740 | } | |
5741 | ||
6aa69784 SRV |
5742 | static void ftrace_free_mod_map(struct rcu_head *rcu) |
5743 | { | |
5744 | struct ftrace_mod_map *mod_map = container_of(rcu, struct ftrace_mod_map, rcu); | |
5745 | struct ftrace_mod_func *mod_func; | |
5746 | struct ftrace_mod_func *n; | |
5747 | ||
5748 | /* All the contents of mod_map are now not visible to readers */ | |
5749 | list_for_each_entry_safe(mod_func, n, &mod_map->funcs, list) { | |
5750 | kfree(mod_func->name); | |
5751 | list_del(&mod_func->list); | |
5752 | kfree(mod_func); | |
5753 | } | |
5754 | ||
5755 | kfree(mod_map); | |
5756 | } | |
5757 | ||
e7247a15 | 5758 | void ftrace_release_mod(struct module *mod) |
93eb677d | 5759 | { |
6aa69784 SRV |
5760 | struct ftrace_mod_map *mod_map; |
5761 | struct ftrace_mod_map *n; | |
93eb677d | 5762 | struct dyn_ftrace *rec; |
32082309 | 5763 | struct ftrace_page **last_pg; |
2a5bfe47 | 5764 | struct ftrace_page *tmp_page = NULL; |
93eb677d | 5765 | struct ftrace_page *pg; |
a7900875 | 5766 | int order; |
93eb677d | 5767 | |
45a4a237 SR |
5768 | mutex_lock(&ftrace_lock); |
5769 | ||
e7247a15 | 5770 | if (ftrace_disabled) |
45a4a237 | 5771 | goto out_unlock; |
93eb677d | 5772 | |
6aa69784 SRV |
5773 | list_for_each_entry_safe(mod_map, n, &ftrace_mod_maps, list) { |
5774 | if (mod_map->mod == mod) { | |
5775 | list_del_rcu(&mod_map->list); | |
74401729 | 5776 | call_rcu(&mod_map->rcu, ftrace_free_mod_map); |
6aa69784 SRV |
5777 | break; |
5778 | } | |
5779 | } | |
5780 | ||
32082309 SR |
5781 | /* |
5782 | * Each module has its own ftrace_pages, remove | |
5783 | * them from the list. | |
5784 | */ | |
5785 | last_pg = &ftrace_pages_start; | |
5786 | for (pg = ftrace_pages_start; pg; pg = *last_pg) { | |
5787 | rec = &pg->records[0]; | |
3e234289 SRV |
5788 | if (within_module_core(rec->ip, mod) || |
5789 | within_module_init(rec->ip, mod)) { | |
93eb677d | 5790 | /* |
32082309 SR |
5791 | * As core pages are first, the first |
5792 | * page should never be a module page. | |
93eb677d | 5793 | */ |
32082309 SR |
5794 | if (WARN_ON(pg == ftrace_pages_start)) |
5795 | goto out_unlock; | |
5796 | ||
5797 | /* Check if we are deleting the last page */ | |
5798 | if (pg == ftrace_pages) | |
5799 | ftrace_pages = next_to_ftrace_page(last_pg); | |
5800 | ||
83dd1493 | 5801 | ftrace_update_tot_cnt -= pg->index; |
32082309 | 5802 | *last_pg = pg->next; |
2a5bfe47 SRV |
5803 | |
5804 | pg->next = tmp_page; | |
5805 | tmp_page = pg; | |
32082309 SR |
5806 | } else |
5807 | last_pg = &pg->next; | |
5808 | } | |
45a4a237 | 5809 | out_unlock: |
93eb677d | 5810 | mutex_unlock(&ftrace_lock); |
2a5bfe47 SRV |
5811 | |
5812 | for (pg = tmp_page; pg; pg = tmp_page) { | |
5813 | ||
5814 | /* Needs to be called outside of ftrace_lock */ | |
5815 | clear_mod_from_hashes(pg); | |
5816 | ||
5817 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); | |
5818 | free_pages((unsigned long)pg->records, order); | |
5819 | tmp_page = pg->next; | |
5820 | kfree(pg); | |
5821 | } | |
93eb677d SR |
5822 | } |
5823 | ||
7dcd182b | 5824 | void ftrace_module_enable(struct module *mod) |
b7ffffbb SRRH |
5825 | { |
5826 | struct dyn_ftrace *rec; | |
5827 | struct ftrace_page *pg; | |
5828 | ||
5829 | mutex_lock(&ftrace_lock); | |
5830 | ||
5831 | if (ftrace_disabled) | |
5832 | goto out_unlock; | |
5833 | ||
5834 | /* | |
5835 | * If the tracing is enabled, go ahead and enable the record. | |
5836 | * | |
9efb85c5 | 5837 | * The reason not to enable the record immediately is the |
b7ffffbb SRRH |
5838 | * inherent check of ftrace_make_nop/ftrace_make_call for |
5839 | * correct previous instructions. Making first the NOP | |
5840 | * conversion puts the module to the correct state, thus | |
5841 | * passing the ftrace_make_call check. | |
5842 | * | |
5843 | * We also delay this to after the module code already set the | |
5844 | * text to read-only, as we now need to set it back to read-write | |
5845 | * so that we can modify the text. | |
5846 | */ | |
5847 | if (ftrace_start_up) | |
5848 | ftrace_arch_code_modify_prepare(); | |
5849 | ||
5850 | do_for_each_ftrace_rec(pg, rec) { | |
5851 | int cnt; | |
5852 | /* | |
5853 | * do_for_each_ftrace_rec() is a double loop. | |
5854 | * module text shares the pg. If a record is | |
5855 | * not part of this module, then skip this pg, | |
5856 | * which the "break" will do. | |
5857 | */ | |
3e234289 SRV |
5858 | if (!within_module_core(rec->ip, mod) && |
5859 | !within_module_init(rec->ip, mod)) | |
b7ffffbb SRRH |
5860 | break; |
5861 | ||
5862 | cnt = 0; | |
5863 | ||
5864 | /* | |
5865 | * When adding a module, we need to check if tracers are | |
5866 | * currently enabled and if they are, and can trace this record, | |
5867 | * we need to enable the module functions as well as update the | |
5868 | * reference counts for those function records. | |
5869 | */ | |
5870 | if (ftrace_start_up) | |
5871 | cnt += referenced_filters(rec); | |
5872 | ||
5873 | /* This clears FTRACE_FL_DISABLED */ | |
5874 | rec->flags = cnt; | |
5875 | ||
5876 | if (ftrace_start_up && cnt) { | |
5877 | int failed = __ftrace_replace_code(rec, 1); | |
5878 | if (failed) { | |
5879 | ftrace_bug(failed, rec); | |
5880 | goto out_loop; | |
5881 | } | |
5882 | } | |
5883 | ||
5884 | } while_for_each_ftrace_rec(); | |
5885 | ||
5886 | out_loop: | |
5887 | if (ftrace_start_up) | |
5888 | ftrace_arch_code_modify_post_process(); | |
5889 | ||
5890 | out_unlock: | |
5891 | mutex_unlock(&ftrace_lock); | |
d7fbf8df SRV |
5892 | |
5893 | process_cached_mods(mod->name); | |
b7ffffbb SRRH |
5894 | } |
5895 | ||
b6b71f66 | 5896 | void ftrace_module_init(struct module *mod) |
90d595fe | 5897 | { |
97e9b4fc | 5898 | if (ftrace_disabled || !mod->num_ftrace_callsites) |
fed1939c | 5899 | return; |
90d595fe | 5900 | |
97e9b4fc SRRH |
5901 | ftrace_process_locs(mod, mod->ftrace_callsites, |
5902 | mod->ftrace_callsites + mod->num_ftrace_callsites); | |
8c189ea6 | 5903 | } |
aba4b5c2 SRV |
5904 | |
5905 | static void save_ftrace_mod_rec(struct ftrace_mod_map *mod_map, | |
5906 | struct dyn_ftrace *rec) | |
5907 | { | |
5908 | struct ftrace_mod_func *mod_func; | |
5909 | unsigned long symsize; | |
5910 | unsigned long offset; | |
5911 | char str[KSYM_SYMBOL_LEN]; | |
5912 | char *modname; | |
5913 | const char *ret; | |
5914 | ||
5915 | ret = kallsyms_lookup(rec->ip, &symsize, &offset, &modname, str); | |
5916 | if (!ret) | |
5917 | return; | |
5918 | ||
5919 | mod_func = kmalloc(sizeof(*mod_func), GFP_KERNEL); | |
5920 | if (!mod_func) | |
5921 | return; | |
5922 | ||
5923 | mod_func->name = kstrdup(str, GFP_KERNEL); | |
5924 | if (!mod_func->name) { | |
5925 | kfree(mod_func); | |
5926 | return; | |
5927 | } | |
5928 | ||
5929 | mod_func->ip = rec->ip - offset; | |
5930 | mod_func->size = symsize; | |
5931 | ||
6171a031 SRV |
5932 | mod_map->num_funcs++; |
5933 | ||
aba4b5c2 SRV |
5934 | list_add_rcu(&mod_func->list, &mod_map->funcs); |
5935 | } | |
5936 | ||
aba4b5c2 SRV |
5937 | static struct ftrace_mod_map * |
5938 | allocate_ftrace_mod_map(struct module *mod, | |
5939 | unsigned long start, unsigned long end) | |
5940 | { | |
5941 | struct ftrace_mod_map *mod_map; | |
5942 | ||
5943 | mod_map = kmalloc(sizeof(*mod_map), GFP_KERNEL); | |
5944 | if (!mod_map) | |
5945 | return NULL; | |
5946 | ||
5947 | mod_map->mod = mod; | |
5948 | mod_map->start_addr = start; | |
5949 | mod_map->end_addr = end; | |
6171a031 | 5950 | mod_map->num_funcs = 0; |
aba4b5c2 SRV |
5951 | |
5952 | INIT_LIST_HEAD_RCU(&mod_map->funcs); | |
5953 | ||
5954 | list_add_rcu(&mod_map->list, &ftrace_mod_maps); | |
5955 | ||
5956 | return mod_map; | |
5957 | } | |
5958 | ||
5959 | static const char * | |
5960 | ftrace_func_address_lookup(struct ftrace_mod_map *mod_map, | |
5961 | unsigned long addr, unsigned long *size, | |
5962 | unsigned long *off, char *sym) | |
5963 | { | |
5964 | struct ftrace_mod_func *found_func = NULL; | |
5965 | struct ftrace_mod_func *mod_func; | |
5966 | ||
5967 | list_for_each_entry_rcu(mod_func, &mod_map->funcs, list) { | |
5968 | if (addr >= mod_func->ip && | |
5969 | addr < mod_func->ip + mod_func->size) { | |
5970 | found_func = mod_func; | |
5971 | break; | |
5972 | } | |
5973 | } | |
5974 | ||
5975 | if (found_func) { | |
5976 | if (size) | |
5977 | *size = found_func->size; | |
5978 | if (off) | |
5979 | *off = addr - found_func->ip; | |
5980 | if (sym) | |
5981 | strlcpy(sym, found_func->name, KSYM_NAME_LEN); | |
5982 | ||
5983 | return found_func->name; | |
5984 | } | |
5985 | ||
5986 | return NULL; | |
5987 | } | |
5988 | ||
5989 | const char * | |
5990 | ftrace_mod_address_lookup(unsigned long addr, unsigned long *size, | |
5991 | unsigned long *off, char **modname, char *sym) | |
5992 | { | |
5993 | struct ftrace_mod_map *mod_map; | |
5994 | const char *ret = NULL; | |
5995 | ||
74401729 | 5996 | /* mod_map is freed via call_rcu() */ |
aba4b5c2 SRV |
5997 | preempt_disable(); |
5998 | list_for_each_entry_rcu(mod_map, &ftrace_mod_maps, list) { | |
5999 | ret = ftrace_func_address_lookup(mod_map, addr, size, off, sym); | |
6000 | if (ret) { | |
6001 | if (modname) | |
6002 | *modname = mod_map->mod->name; | |
6003 | break; | |
6004 | } | |
6005 | } | |
6006 | preempt_enable(); | |
6007 | ||
6008 | return ret; | |
6009 | } | |
6010 | ||
6171a031 SRV |
6011 | int ftrace_mod_get_kallsym(unsigned int symnum, unsigned long *value, |
6012 | char *type, char *name, | |
6013 | char *module_name, int *exported) | |
6014 | { | |
6015 | struct ftrace_mod_map *mod_map; | |
6016 | struct ftrace_mod_func *mod_func; | |
6017 | ||
6018 | preempt_disable(); | |
6019 | list_for_each_entry_rcu(mod_map, &ftrace_mod_maps, list) { | |
6020 | ||
6021 | if (symnum >= mod_map->num_funcs) { | |
6022 | symnum -= mod_map->num_funcs; | |
6023 | continue; | |
6024 | } | |
6025 | ||
6026 | list_for_each_entry_rcu(mod_func, &mod_map->funcs, list) { | |
6027 | if (symnum > 1) { | |
6028 | symnum--; | |
6029 | continue; | |
6030 | } | |
6031 | ||
6032 | *value = mod_func->ip; | |
6033 | *type = 'T'; | |
6034 | strlcpy(name, mod_func->name, KSYM_NAME_LEN); | |
6035 | strlcpy(module_name, mod_map->mod->name, MODULE_NAME_LEN); | |
6036 | *exported = 1; | |
6037 | preempt_enable(); | |
6038 | return 0; | |
6039 | } | |
6040 | WARN_ON(1); | |
6041 | break; | |
6042 | } | |
6043 | preempt_enable(); | |
6044 | return -ERANGE; | |
6045 | } | |
6046 | ||
aba4b5c2 SRV |
6047 | #else |
6048 | static void save_ftrace_mod_rec(struct ftrace_mod_map *mod_map, | |
6049 | struct dyn_ftrace *rec) { } | |
6050 | static inline struct ftrace_mod_map * | |
6051 | allocate_ftrace_mod_map(struct module *mod, | |
6052 | unsigned long start, unsigned long end) | |
6053 | { | |
6054 | return NULL; | |
6055 | } | |
93eb677d SR |
6056 | #endif /* CONFIG_MODULES */ |
6057 | ||
8715b108 JF |
6058 | struct ftrace_init_func { |
6059 | struct list_head list; | |
6060 | unsigned long ip; | |
6061 | }; | |
6062 | ||
6063 | /* Clear any init ips from hashes */ | |
6064 | static void | |
6065 | clear_func_from_hash(struct ftrace_init_func *func, struct ftrace_hash *hash) | |
42c269c8 | 6066 | { |
8715b108 JF |
6067 | struct ftrace_func_entry *entry; |
6068 | ||
08468754 | 6069 | entry = ftrace_lookup_ip(hash, func->ip); |
8715b108 JF |
6070 | /* |
6071 | * Do not allow this rec to match again. | |
6072 | * Yeah, it may waste some memory, but will be removed | |
6073 | * if/when the hash is modified again. | |
6074 | */ | |
6075 | if (entry) | |
6076 | entry->ip = 0; | |
6077 | } | |
6078 | ||
6079 | static void | |
6080 | clear_func_from_hashes(struct ftrace_init_func *func) | |
6081 | { | |
6082 | struct trace_array *tr; | |
6083 | ||
6084 | mutex_lock(&trace_types_lock); | |
6085 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6086 | if (!tr->ops || !tr->ops->func_hash) | |
6087 | continue; | |
6088 | mutex_lock(&tr->ops->func_hash->regex_lock); | |
6089 | clear_func_from_hash(func, tr->ops->func_hash->filter_hash); | |
6090 | clear_func_from_hash(func, tr->ops->func_hash->notrace_hash); | |
6091 | mutex_unlock(&tr->ops->func_hash->regex_lock); | |
6092 | } | |
6093 | mutex_unlock(&trace_types_lock); | |
6094 | } | |
6095 | ||
6096 | static void add_to_clear_hash_list(struct list_head *clear_list, | |
6097 | struct dyn_ftrace *rec) | |
6098 | { | |
6099 | struct ftrace_init_func *func; | |
6100 | ||
6101 | func = kmalloc(sizeof(*func), GFP_KERNEL); | |
6102 | if (!func) { | |
6103 | WARN_ONCE(1, "alloc failure, ftrace filter could be stale\n"); | |
6104 | return; | |
6105 | } | |
6106 | ||
6107 | func->ip = rec->ip; | |
6108 | list_add(&func->list, clear_list); | |
6109 | } | |
6110 | ||
aba4b5c2 | 6111 | void ftrace_free_mem(struct module *mod, void *start_ptr, void *end_ptr) |
42c269c8 | 6112 | { |
6cafbe15 SRV |
6113 | unsigned long start = (unsigned long)(start_ptr); |
6114 | unsigned long end = (unsigned long)(end_ptr); | |
42c269c8 SRV |
6115 | struct ftrace_page **last_pg = &ftrace_pages_start; |
6116 | struct ftrace_page *pg; | |
6117 | struct dyn_ftrace *rec; | |
6118 | struct dyn_ftrace key; | |
aba4b5c2 | 6119 | struct ftrace_mod_map *mod_map = NULL; |
8715b108 JF |
6120 | struct ftrace_init_func *func, *func_next; |
6121 | struct list_head clear_hash; | |
42c269c8 SRV |
6122 | int order; |
6123 | ||
8715b108 JF |
6124 | INIT_LIST_HEAD(&clear_hash); |
6125 | ||
42c269c8 SRV |
6126 | key.ip = start; |
6127 | key.flags = end; /* overload flags, as it is unsigned long */ | |
6128 | ||
6129 | mutex_lock(&ftrace_lock); | |
6130 | ||
aba4b5c2 SRV |
6131 | /* |
6132 | * If we are freeing module init memory, then check if | |
6133 | * any tracer is active. If so, we need to save a mapping of | |
6134 | * the module functions being freed with the address. | |
6135 | */ | |
6136 | if (mod && ftrace_ops_list != &ftrace_list_end) | |
6137 | mod_map = allocate_ftrace_mod_map(mod, start, end); | |
6138 | ||
42c269c8 SRV |
6139 | for (pg = ftrace_pages_start; pg; last_pg = &pg->next, pg = *last_pg) { |
6140 | if (end < pg->records[0].ip || | |
6141 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) | |
6142 | continue; | |
6143 | again: | |
6144 | rec = bsearch(&key, pg->records, pg->index, | |
6145 | sizeof(struct dyn_ftrace), | |
6146 | ftrace_cmp_recs); | |
6147 | if (!rec) | |
6148 | continue; | |
aba4b5c2 | 6149 | |
8715b108 JF |
6150 | /* rec will be cleared from hashes after ftrace_lock unlock */ |
6151 | add_to_clear_hash_list(&clear_hash, rec); | |
6152 | ||
aba4b5c2 SRV |
6153 | if (mod_map) |
6154 | save_ftrace_mod_rec(mod_map, rec); | |
6155 | ||
42c269c8 | 6156 | pg->index--; |
4ec78467 | 6157 | ftrace_update_tot_cnt--; |
42c269c8 SRV |
6158 | if (!pg->index) { |
6159 | *last_pg = pg->next; | |
6160 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); | |
6161 | free_pages((unsigned long)pg->records, order); | |
6162 | kfree(pg); | |
6163 | pg = container_of(last_pg, struct ftrace_page, next); | |
6164 | if (!(*last_pg)) | |
6165 | ftrace_pages = pg; | |
6166 | continue; | |
6167 | } | |
6168 | memmove(rec, rec + 1, | |
6169 | (pg->index - (rec - pg->records)) * sizeof(*rec)); | |
6170 | /* More than one function may be in this block */ | |
6171 | goto again; | |
6172 | } | |
6173 | mutex_unlock(&ftrace_lock); | |
8715b108 JF |
6174 | |
6175 | list_for_each_entry_safe(func, func_next, &clear_hash, list) { | |
6176 | clear_func_from_hashes(func); | |
6177 | kfree(func); | |
6178 | } | |
42c269c8 SRV |
6179 | } |
6180 | ||
6cafbe15 SRV |
6181 | void __init ftrace_free_init_mem(void) |
6182 | { | |
6183 | void *start = (void *)(&__init_begin); | |
6184 | void *end = (void *)(&__init_end); | |
6185 | ||
aba4b5c2 | 6186 | ftrace_free_mem(NULL, start, end); |
42c269c8 SRV |
6187 | } |
6188 | ||
68bf21aa SR |
6189 | void __init ftrace_init(void) |
6190 | { | |
1dc43cf0 JS |
6191 | extern unsigned long __start_mcount_loc[]; |
6192 | extern unsigned long __stop_mcount_loc[]; | |
3a36cb11 | 6193 | unsigned long count, flags; |
68bf21aa SR |
6194 | int ret; |
6195 | ||
68bf21aa | 6196 | local_irq_save(flags); |
3a36cb11 | 6197 | ret = ftrace_dyn_arch_init(); |
68bf21aa | 6198 | local_irq_restore(flags); |
af64a7cb | 6199 | if (ret) |
68bf21aa SR |
6200 | goto failed; |
6201 | ||
6202 | count = __stop_mcount_loc - __start_mcount_loc; | |
c867ccd8 JS |
6203 | if (!count) { |
6204 | pr_info("ftrace: No functions to be traced?\n"); | |
68bf21aa | 6205 | goto failed; |
c867ccd8 JS |
6206 | } |
6207 | ||
6208 | pr_info("ftrace: allocating %ld entries in %ld pages\n", | |
6209 | count, count / ENTRIES_PER_PAGE + 1); | |
68bf21aa SR |
6210 | |
6211 | last_ftrace_enabled = ftrace_enabled = 1; | |
6212 | ||
5cb084bb | 6213 | ret = ftrace_process_locs(NULL, |
31e88909 | 6214 | __start_mcount_loc, |
68bf21aa SR |
6215 | __stop_mcount_loc); |
6216 | ||
2af15d6a SR |
6217 | set_ftrace_early_filters(); |
6218 | ||
68bf21aa SR |
6219 | return; |
6220 | failed: | |
6221 | ftrace_disabled = 1; | |
6222 | } | |
68bf21aa | 6223 | |
f3bea491 SRRH |
6224 | /* Do nothing if arch does not support this */ |
6225 | void __weak arch_ftrace_update_trampoline(struct ftrace_ops *ops) | |
6226 | { | |
6227 | } | |
6228 | ||
6229 | static void ftrace_update_trampoline(struct ftrace_ops *ops) | |
6230 | { | |
f3bea491 SRRH |
6231 | arch_ftrace_update_trampoline(ops); |
6232 | } | |
6233 | ||
04ec7bb6 SRV |
6234 | void ftrace_init_trace_array(struct trace_array *tr) |
6235 | { | |
6236 | INIT_LIST_HEAD(&tr->func_probes); | |
673feb9d SRV |
6237 | INIT_LIST_HEAD(&tr->mod_trace); |
6238 | INIT_LIST_HEAD(&tr->mod_notrace); | |
04ec7bb6 | 6239 | } |
3d083395 | 6240 | #else |
0b6e4d56 | 6241 | |
3306fc4a | 6242 | struct ftrace_ops global_ops = { |
bd69c30b | 6243 | .func = ftrace_stub, |
e3eea140 SRRH |
6244 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | |
6245 | FTRACE_OPS_FL_INITIALIZED | | |
6246 | FTRACE_OPS_FL_PID, | |
bd69c30b SR |
6247 | }; |
6248 | ||
0b6e4d56 FW |
6249 | static int __init ftrace_nodyn_init(void) |
6250 | { | |
6251 | ftrace_enabled = 1; | |
6252 | return 0; | |
6253 | } | |
6f415672 | 6254 | core_initcall(ftrace_nodyn_init); |
0b6e4d56 | 6255 | |
8434dc93 | 6256 | static inline int ftrace_init_dyn_tracefs(struct dentry *d_tracer) { return 0; } |
df4fc315 | 6257 | static inline void ftrace_startup_enable(int command) { } |
e1effa01 | 6258 | static inline void ftrace_startup_all(int command) { } |
8a56d776 | 6259 | |
c7aafc54 IM |
6260 | # define ftrace_startup_sysctl() do { } while (0) |
6261 | # define ftrace_shutdown_sysctl() do { } while (0) | |
b848914c | 6262 | |
f3bea491 SRRH |
6263 | static void ftrace_update_trampoline(struct ftrace_ops *ops) |
6264 | { | |
6265 | } | |
6266 | ||
3d083395 SR |
6267 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
6268 | ||
4104d326 SRRH |
6269 | __init void ftrace_init_global_array_ops(struct trace_array *tr) |
6270 | { | |
6271 | tr->ops = &global_ops; | |
6272 | tr->ops->private = tr; | |
04ec7bb6 | 6273 | ftrace_init_trace_array(tr); |
4104d326 SRRH |
6274 | } |
6275 | ||
6276 | void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func) | |
6277 | { | |
6278 | /* If we filter on pids, update to use the pid function */ | |
6279 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { | |
6280 | if (WARN_ON(tr->ops->func != ftrace_stub)) | |
6281 | printk("ftrace ops had %pS for function\n", | |
6282 | tr->ops->func); | |
4104d326 SRRH |
6283 | } |
6284 | tr->ops->func = func; | |
6285 | tr->ops->private = tr; | |
6286 | } | |
6287 | ||
6288 | void ftrace_reset_array_ops(struct trace_array *tr) | |
6289 | { | |
6290 | tr->ops->func = ftrace_stub; | |
6291 | } | |
6292 | ||
fabe38ab | 6293 | static nokprobe_inline void |
2f5f6ad9 | 6294 | __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 6295 | struct ftrace_ops *ignored, struct pt_regs *regs) |
b848914c | 6296 | { |
cdbe61bf | 6297 | struct ftrace_ops *op; |
edc15caf | 6298 | int bit; |
b848914c | 6299 | |
edc15caf SR |
6300 | bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); |
6301 | if (bit < 0) | |
6302 | return; | |
b1cff0ad | 6303 | |
cdbe61bf SR |
6304 | /* |
6305 | * Some of the ops may be dynamically allocated, | |
74401729 | 6306 | * they must be freed after a synchronize_rcu(). |
cdbe61bf SR |
6307 | */ |
6308 | preempt_disable_notrace(); | |
ba27f2bc | 6309 | |
0a016409 | 6310 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
2fa717a0 SRV |
6311 | /* Stub functions don't need to be called nor tested */ |
6312 | if (op->flags & FTRACE_OPS_FL_STUB) | |
6313 | continue; | |
ba27f2bc SRRH |
6314 | /* |
6315 | * Check the following for each ops before calling their func: | |
6316 | * if RCU flag is set, then rcu_is_watching() must be true | |
6317 | * if PER_CPU is set, then ftrace_function_local_disable() | |
6318 | * must be false | |
6319 | * Otherwise test if the ip matches the ops filter | |
6320 | * | |
6321 | * If any of the above fails then the op->func() is not executed. | |
6322 | */ | |
6323 | if ((!(op->flags & FTRACE_OPS_FL_RCU) || rcu_is_watching()) && | |
ba27f2bc | 6324 | ftrace_ops_test(op, ip, regs)) { |
1d48d596 SRRH |
6325 | if (FTRACE_WARN_ON(!op->func)) { |
6326 | pr_warn("op=%p %pS\n", op, op); | |
4104d326 SRRH |
6327 | goto out; |
6328 | } | |
a1e2e31d | 6329 | op->func(ip, parent_ip, op, regs); |
4104d326 | 6330 | } |
0a016409 | 6331 | } while_for_each_ftrace_op(op); |
4104d326 | 6332 | out: |
cdbe61bf | 6333 | preempt_enable_notrace(); |
edc15caf | 6334 | trace_clear_recursion(bit); |
b848914c SR |
6335 | } |
6336 | ||
2f5f6ad9 SR |
6337 | /* |
6338 | * Some archs only support passing ip and parent_ip. Even though | |
6339 | * the list function ignores the op parameter, we do not want any | |
6340 | * C side effects, where a function is called without the caller | |
6341 | * sending a third parameter. | |
a1e2e31d SR |
6342 | * Archs are to support both the regs and ftrace_ops at the same time. |
6343 | * If they support ftrace_ops, it is assumed they support regs. | |
6344 | * If call backs want to use regs, they must either check for regs | |
06aeaaea MH |
6345 | * being NULL, or CONFIG_DYNAMIC_FTRACE_WITH_REGS. |
6346 | * Note, CONFIG_DYNAMIC_FTRACE_WITH_REGS expects a full regs to be saved. | |
a1e2e31d | 6347 | * An architecture can pass partial regs with ftrace_ops and still |
b8ec330a | 6348 | * set the ARCH_SUPPORTS_FTRACE_OPS. |
2f5f6ad9 SR |
6349 | */ |
6350 | #if ARCH_SUPPORTS_FTRACE_OPS | |
6351 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 6352 | struct ftrace_ops *op, struct pt_regs *regs) |
2f5f6ad9 | 6353 | { |
a1e2e31d | 6354 | __ftrace_ops_list_func(ip, parent_ip, NULL, regs); |
2f5f6ad9 | 6355 | } |
fabe38ab | 6356 | NOKPROBE_SYMBOL(ftrace_ops_list_func); |
2f5f6ad9 SR |
6357 | #else |
6358 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip) | |
6359 | { | |
a1e2e31d | 6360 | __ftrace_ops_list_func(ip, parent_ip, NULL, NULL); |
2f5f6ad9 | 6361 | } |
fabe38ab | 6362 | NOKPROBE_SYMBOL(ftrace_ops_no_ops); |
2f5f6ad9 SR |
6363 | #endif |
6364 | ||
f1ff6348 SRRH |
6365 | /* |
6366 | * If there's only one function registered but it does not support | |
c68c0fa2 SRRH |
6367 | * recursion, needs RCU protection and/or requires per cpu handling, then |
6368 | * this function will be called by the mcount trampoline. | |
f1ff6348 | 6369 | */ |
c68c0fa2 | 6370 | static void ftrace_ops_assist_func(unsigned long ip, unsigned long parent_ip, |
f1ff6348 SRRH |
6371 | struct ftrace_ops *op, struct pt_regs *regs) |
6372 | { | |
6373 | int bit; | |
6374 | ||
c68c0fa2 SRRH |
6375 | if ((op->flags & FTRACE_OPS_FL_RCU) && !rcu_is_watching()) |
6376 | return; | |
6377 | ||
f1ff6348 SRRH |
6378 | bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); |
6379 | if (bit < 0) | |
6380 | return; | |
6381 | ||
c68c0fa2 | 6382 | preempt_disable_notrace(); |
f1ff6348 | 6383 | |
b3a88803 | 6384 | op->func(ip, parent_ip, op, regs); |
c68c0fa2 SRRH |
6385 | |
6386 | preempt_enable_notrace(); | |
f1ff6348 SRRH |
6387 | trace_clear_recursion(bit); |
6388 | } | |
fabe38ab | 6389 | NOKPROBE_SYMBOL(ftrace_ops_assist_func); |
f1ff6348 | 6390 | |
87354059 SRRH |
6391 | /** |
6392 | * ftrace_ops_get_func - get the function a trampoline should call | |
6393 | * @ops: the ops to get the function for | |
6394 | * | |
6395 | * Normally the mcount trampoline will call the ops->func, but there | |
6396 | * are times that it should not. For example, if the ops does not | |
6397 | * have its own recursion protection, then it should call the | |
3a150df9 | 6398 | * ftrace_ops_assist_func() instead. |
87354059 SRRH |
6399 | * |
6400 | * Returns the function that the trampoline should call for @ops. | |
6401 | */ | |
6402 | ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops) | |
6403 | { | |
87354059 | 6404 | /* |
c68c0fa2 SRRH |
6405 | * If the function does not handle recursion, needs to be RCU safe, |
6406 | * or does per cpu logic, then we need to call the assist handler. | |
87354059 | 6407 | */ |
c68c0fa2 | 6408 | if (!(ops->flags & FTRACE_OPS_FL_RECURSION_SAFE) || |
b3a88803 | 6409 | ops->flags & FTRACE_OPS_FL_RCU) |
c68c0fa2 | 6410 | return ftrace_ops_assist_func; |
87354059 SRRH |
6411 | |
6412 | return ops->func; | |
6413 | } | |
6414 | ||
345ddcc8 SRRH |
6415 | static void |
6416 | ftrace_filter_pid_sched_switch_probe(void *data, bool preempt, | |
6417 | struct task_struct *prev, struct task_struct *next) | |
978f3a45 | 6418 | { |
345ddcc8 SRRH |
6419 | struct trace_array *tr = data; |
6420 | struct trace_pid_list *pid_list; | |
978f3a45 | 6421 | |
345ddcc8 | 6422 | pid_list = rcu_dereference_sched(tr->function_pids); |
e32d8956 | 6423 | |
345ddcc8 SRRH |
6424 | this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid, |
6425 | trace_ignore_this_task(pid_list, next)); | |
978f3a45 SR |
6426 | } |
6427 | ||
1e10486f NK |
6428 | static void |
6429 | ftrace_pid_follow_sched_process_fork(void *data, | |
6430 | struct task_struct *self, | |
6431 | struct task_struct *task) | |
6432 | { | |
6433 | struct trace_pid_list *pid_list; | |
6434 | struct trace_array *tr = data; | |
6435 | ||
6436 | pid_list = rcu_dereference_sched(tr->function_pids); | |
6437 | trace_filter_add_remove_task(pid_list, self, task); | |
6438 | } | |
6439 | ||
6440 | static void | |
6441 | ftrace_pid_follow_sched_process_exit(void *data, struct task_struct *task) | |
6442 | { | |
6443 | struct trace_pid_list *pid_list; | |
6444 | struct trace_array *tr = data; | |
6445 | ||
6446 | pid_list = rcu_dereference_sched(tr->function_pids); | |
6447 | trace_filter_add_remove_task(pid_list, NULL, task); | |
6448 | } | |
6449 | ||
6450 | void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) | |
6451 | { | |
6452 | if (enable) { | |
6453 | register_trace_sched_process_fork(ftrace_pid_follow_sched_process_fork, | |
6454 | tr); | |
6455 | register_trace_sched_process_exit(ftrace_pid_follow_sched_process_exit, | |
6456 | tr); | |
6457 | } else { | |
6458 | unregister_trace_sched_process_fork(ftrace_pid_follow_sched_process_fork, | |
6459 | tr); | |
6460 | unregister_trace_sched_process_exit(ftrace_pid_follow_sched_process_exit, | |
6461 | tr); | |
6462 | } | |
6463 | } | |
6464 | ||
345ddcc8 | 6465 | static void clear_ftrace_pids(struct trace_array *tr) |
e32d8956 | 6466 | { |
345ddcc8 SRRH |
6467 | struct trace_pid_list *pid_list; |
6468 | int cpu; | |
e32d8956 | 6469 | |
345ddcc8 SRRH |
6470 | pid_list = rcu_dereference_protected(tr->function_pids, |
6471 | lockdep_is_held(&ftrace_lock)); | |
6472 | if (!pid_list) | |
6473 | return; | |
229c4ef8 | 6474 | |
345ddcc8 | 6475 | unregister_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr); |
e32d8956 | 6476 | |
345ddcc8 SRRH |
6477 | for_each_possible_cpu(cpu) |
6478 | per_cpu_ptr(tr->trace_buffer.data, cpu)->ftrace_ignore_pid = false; | |
978f3a45 | 6479 | |
345ddcc8 | 6480 | rcu_assign_pointer(tr->function_pids, NULL); |
978f3a45 | 6481 | |
345ddcc8 | 6482 | /* Wait till all users are no longer using pid filtering */ |
74401729 | 6483 | synchronize_rcu(); |
e32d8956 | 6484 | |
345ddcc8 | 6485 | trace_free_pid_list(pid_list); |
e32d8956 SR |
6486 | } |
6487 | ||
d879d0b8 NK |
6488 | void ftrace_clear_pids(struct trace_array *tr) |
6489 | { | |
6490 | mutex_lock(&ftrace_lock); | |
6491 | ||
6492 | clear_ftrace_pids(tr); | |
6493 | ||
6494 | mutex_unlock(&ftrace_lock); | |
6495 | } | |
6496 | ||
345ddcc8 | 6497 | static void ftrace_pid_reset(struct trace_array *tr) |
df4fc315 | 6498 | { |
756d17ee | 6499 | mutex_lock(&ftrace_lock); |
345ddcc8 | 6500 | clear_ftrace_pids(tr); |
978f3a45 | 6501 | |
756d17ee | 6502 | ftrace_update_pid_func(); |
e1effa01 | 6503 | ftrace_startup_all(0); |
756d17ee | 6504 | |
6505 | mutex_unlock(&ftrace_lock); | |
756d17ee | 6506 | } |
6507 | ||
345ddcc8 SRRH |
6508 | /* Greater than any max PID */ |
6509 | #define FTRACE_NO_PIDS (void *)(PID_MAX_LIMIT + 1) | |
df4fc315 | 6510 | |
756d17ee | 6511 | static void *fpid_start(struct seq_file *m, loff_t *pos) |
345ddcc8 | 6512 | __acquires(RCU) |
756d17ee | 6513 | { |
345ddcc8 SRRH |
6514 | struct trace_pid_list *pid_list; |
6515 | struct trace_array *tr = m->private; | |
6516 | ||
756d17ee | 6517 | mutex_lock(&ftrace_lock); |
345ddcc8 SRRH |
6518 | rcu_read_lock_sched(); |
6519 | ||
6520 | pid_list = rcu_dereference_sched(tr->function_pids); | |
756d17ee | 6521 | |
345ddcc8 SRRH |
6522 | if (!pid_list) |
6523 | return !(*pos) ? FTRACE_NO_PIDS : NULL; | |
756d17ee | 6524 | |
345ddcc8 | 6525 | return trace_pid_start(pid_list, pos); |
756d17ee | 6526 | } |
6527 | ||
6528 | static void *fpid_next(struct seq_file *m, void *v, loff_t *pos) | |
6529 | { | |
345ddcc8 SRRH |
6530 | struct trace_array *tr = m->private; |
6531 | struct trace_pid_list *pid_list = rcu_dereference_sched(tr->function_pids); | |
6532 | ||
6533 | if (v == FTRACE_NO_PIDS) | |
756d17ee | 6534 | return NULL; |
6535 | ||
345ddcc8 | 6536 | return trace_pid_next(pid_list, v, pos); |
756d17ee | 6537 | } |
6538 | ||
6539 | static void fpid_stop(struct seq_file *m, void *p) | |
345ddcc8 | 6540 | __releases(RCU) |
756d17ee | 6541 | { |
345ddcc8 | 6542 | rcu_read_unlock_sched(); |
756d17ee | 6543 | mutex_unlock(&ftrace_lock); |
6544 | } | |
6545 | ||
6546 | static int fpid_show(struct seq_file *m, void *v) | |
6547 | { | |
345ddcc8 | 6548 | if (v == FTRACE_NO_PIDS) { |
fa6f0cc7 | 6549 | seq_puts(m, "no pid\n"); |
756d17ee | 6550 | return 0; |
6551 | } | |
6552 | ||
345ddcc8 | 6553 | return trace_pid_show(m, v); |
756d17ee | 6554 | } |
6555 | ||
6556 | static const struct seq_operations ftrace_pid_sops = { | |
6557 | .start = fpid_start, | |
6558 | .next = fpid_next, | |
6559 | .stop = fpid_stop, | |
6560 | .show = fpid_show, | |
6561 | }; | |
6562 | ||
6563 | static int | |
6564 | ftrace_pid_open(struct inode *inode, struct file *file) | |
6565 | { | |
345ddcc8 SRRH |
6566 | struct trace_array *tr = inode->i_private; |
6567 | struct seq_file *m; | |
756d17ee | 6568 | int ret = 0; |
6569 | ||
8530dec6 SRV |
6570 | ret = tracing_check_open_get_tr(tr); |
6571 | if (ret) | |
6572 | return ret; | |
345ddcc8 | 6573 | |
756d17ee | 6574 | if ((file->f_mode & FMODE_WRITE) && |
6575 | (file->f_flags & O_TRUNC)) | |
345ddcc8 | 6576 | ftrace_pid_reset(tr); |
756d17ee | 6577 | |
345ddcc8 SRRH |
6578 | ret = seq_open(file, &ftrace_pid_sops); |
6579 | if (ret < 0) { | |
6580 | trace_array_put(tr); | |
6581 | } else { | |
6582 | m = file->private_data; | |
6583 | /* copy tr over to seq ops */ | |
6584 | m->private = tr; | |
6585 | } | |
756d17ee | 6586 | |
6587 | return ret; | |
6588 | } | |
6589 | ||
345ddcc8 SRRH |
6590 | static void ignore_task_cpu(void *data) |
6591 | { | |
6592 | struct trace_array *tr = data; | |
6593 | struct trace_pid_list *pid_list; | |
6594 | ||
6595 | /* | |
6596 | * This function is called by on_each_cpu() while the | |
6597 | * event_mutex is held. | |
6598 | */ | |
6599 | pid_list = rcu_dereference_protected(tr->function_pids, | |
6600 | mutex_is_locked(&ftrace_lock)); | |
6601 | ||
6602 | this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid, | |
6603 | trace_ignore_this_task(pid_list, current)); | |
6604 | } | |
6605 | ||
df4fc315 SR |
6606 | static ssize_t |
6607 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
6608 | size_t cnt, loff_t *ppos) | |
6609 | { | |
345ddcc8 SRRH |
6610 | struct seq_file *m = filp->private_data; |
6611 | struct trace_array *tr = m->private; | |
6612 | struct trace_pid_list *filtered_pids = NULL; | |
6613 | struct trace_pid_list *pid_list; | |
6614 | ssize_t ret; | |
df4fc315 | 6615 | |
345ddcc8 SRRH |
6616 | if (!cnt) |
6617 | return 0; | |
6618 | ||
6619 | mutex_lock(&ftrace_lock); | |
6620 | ||
6621 | filtered_pids = rcu_dereference_protected(tr->function_pids, | |
6622 | lockdep_is_held(&ftrace_lock)); | |
6623 | ||
6624 | ret = trace_pid_write(filtered_pids, &pid_list, ubuf, cnt); | |
6625 | if (ret < 0) | |
6626 | goto out; | |
df4fc315 | 6627 | |
345ddcc8 | 6628 | rcu_assign_pointer(tr->function_pids, pid_list); |
df4fc315 | 6629 | |
345ddcc8 | 6630 | if (filtered_pids) { |
74401729 | 6631 | synchronize_rcu(); |
345ddcc8 SRRH |
6632 | trace_free_pid_list(filtered_pids); |
6633 | } else if (pid_list) { | |
6634 | /* Register a probe to set whether to ignore the tracing of a task */ | |
6635 | register_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr); | |
6636 | } | |
df4fc315 | 6637 | |
756d17ee | 6638 | /* |
345ddcc8 SRRH |
6639 | * Ignoring of pids is done at task switch. But we have to |
6640 | * check for those tasks that are currently running. | |
6641 | * Always do this in case a pid was appended or removed. | |
756d17ee | 6642 | */ |
345ddcc8 | 6643 | on_each_cpu(ignore_task_cpu, tr, 1); |
756d17ee | 6644 | |
345ddcc8 SRRH |
6645 | ftrace_update_pid_func(); |
6646 | ftrace_startup_all(0); | |
6647 | out: | |
6648 | mutex_unlock(&ftrace_lock); | |
df4fc315 | 6649 | |
345ddcc8 SRRH |
6650 | if (ret > 0) |
6651 | *ppos += ret; | |
df4fc315 | 6652 | |
345ddcc8 | 6653 | return ret; |
756d17ee | 6654 | } |
df4fc315 | 6655 | |
756d17ee | 6656 | static int |
6657 | ftrace_pid_release(struct inode *inode, struct file *file) | |
6658 | { | |
345ddcc8 | 6659 | struct trace_array *tr = inode->i_private; |
df4fc315 | 6660 | |
345ddcc8 SRRH |
6661 | trace_array_put(tr); |
6662 | ||
6663 | return seq_release(inode, file); | |
df4fc315 SR |
6664 | } |
6665 | ||
5e2336a0 | 6666 | static const struct file_operations ftrace_pid_fops = { |
756d17ee | 6667 | .open = ftrace_pid_open, |
6668 | .write = ftrace_pid_write, | |
6669 | .read = seq_read, | |
098c879e | 6670 | .llseek = tracing_lseek, |
756d17ee | 6671 | .release = ftrace_pid_release, |
df4fc315 SR |
6672 | }; |
6673 | ||
345ddcc8 | 6674 | void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
df4fc315 | 6675 | { |
5452af66 | 6676 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
345ddcc8 | 6677 | tr, &ftrace_pid_fops); |
df4fc315 | 6678 | } |
df4fc315 | 6679 | |
501c2375 SRRH |
6680 | void __init ftrace_init_tracefs_toplevel(struct trace_array *tr, |
6681 | struct dentry *d_tracer) | |
6682 | { | |
6683 | /* Only the top level directory has the dyn_tracefs and profile */ | |
6684 | WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); | |
6685 | ||
6686 | ftrace_init_dyn_tracefs(d_tracer); | |
6687 | ftrace_profile_tracefs(d_tracer); | |
6688 | } | |
6689 | ||
a2bb6a3d | 6690 | /** |
81adbdc0 | 6691 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
6692 | * |
6693 | * This function should be used by panic code. It stops ftrace | |
6694 | * but in a not so nice way. If you need to simply kill ftrace | |
6695 | * from a non-atomic section, use ftrace_kill. | |
6696 | */ | |
81adbdc0 | 6697 | void ftrace_kill(void) |
a2bb6a3d SR |
6698 | { |
6699 | ftrace_disabled = 1; | |
6700 | ftrace_enabled = 0; | |
5ccba64a | 6701 | ftrace_trace_function = ftrace_stub; |
a2bb6a3d SR |
6702 | } |
6703 | ||
e0a413f6 SR |
6704 | /** |
6705 | * Test if ftrace is dead or not. | |
6706 | */ | |
6707 | int ftrace_is_dead(void) | |
6708 | { | |
6709 | return ftrace_disabled; | |
6710 | } | |
6711 | ||
16444a8a | 6712 | /** |
3d083395 SR |
6713 | * register_ftrace_function - register a function for profiling |
6714 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 6715 | * |
3d083395 SR |
6716 | * Register a function to be called by all functions in the |
6717 | * kernel. | |
6718 | * | |
6719 | * Note: @ops->func and all the functions it calls must be labeled | |
6720 | * with "notrace", otherwise it will go into a | |
6721 | * recursive loop. | |
16444a8a | 6722 | */ |
3d083395 | 6723 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 6724 | { |
45a4a237 | 6725 | int ret = -1; |
4eebcc81 | 6726 | |
f04f24fb MH |
6727 | ftrace_ops_init(ops); |
6728 | ||
e6ea44e9 | 6729 | mutex_lock(&ftrace_lock); |
e7d3737e | 6730 | |
8a56d776 | 6731 | ret = ftrace_startup(ops, 0); |
b848914c | 6732 | |
e6ea44e9 | 6733 | mutex_unlock(&ftrace_lock); |
8d240dd8 | 6734 | |
b0fc494f | 6735 | return ret; |
3d083395 | 6736 | } |
cdbe61bf | 6737 | EXPORT_SYMBOL_GPL(register_ftrace_function); |
3d083395 SR |
6738 | |
6739 | /** | |
32632920 | 6740 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
6741 | * @ops - ops structure that holds the function to unregister |
6742 | * | |
6743 | * Unregister a function that was added to be called by ftrace profiling. | |
6744 | */ | |
6745 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
6746 | { | |
6747 | int ret; | |
6748 | ||
e6ea44e9 | 6749 | mutex_lock(&ftrace_lock); |
8a56d776 | 6750 | ret = ftrace_shutdown(ops, 0); |
e6ea44e9 | 6751 | mutex_unlock(&ftrace_lock); |
b0fc494f SR |
6752 | |
6753 | return ret; | |
6754 | } | |
cdbe61bf | 6755 | EXPORT_SYMBOL_GPL(unregister_ftrace_function); |
b0fc494f | 6756 | |
e309b41d | 6757 | int |
b0fc494f | 6758 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
8d65af78 | 6759 | void __user *buffer, size_t *lenp, |
b0fc494f SR |
6760 | loff_t *ppos) |
6761 | { | |
45a4a237 | 6762 | int ret = -ENODEV; |
4eebcc81 | 6763 | |
e6ea44e9 | 6764 | mutex_lock(&ftrace_lock); |
b0fc494f | 6765 | |
45a4a237 SR |
6766 | if (unlikely(ftrace_disabled)) |
6767 | goto out; | |
6768 | ||
6769 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
b0fc494f | 6770 | |
a32c7765 | 6771 | if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) |
b0fc494f SR |
6772 | goto out; |
6773 | ||
a32c7765 | 6774 | last_ftrace_enabled = !!ftrace_enabled; |
b0fc494f SR |
6775 | |
6776 | if (ftrace_enabled) { | |
6777 | ||
b0fc494f | 6778 | /* we are starting ftrace again */ |
f86f4180 CZ |
6779 | if (rcu_dereference_protected(ftrace_ops_list, |
6780 | lockdep_is_held(&ftrace_lock)) != &ftrace_list_end) | |
5000c418 | 6781 | update_ftrace_function(); |
b0fc494f | 6782 | |
524a3868 SRRH |
6783 | ftrace_startup_sysctl(); |
6784 | ||
b0fc494f SR |
6785 | } else { |
6786 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
6787 | ftrace_trace_function = ftrace_stub; | |
6788 | ||
6789 | ftrace_shutdown_sysctl(); | |
6790 | } | |
6791 | ||
6792 | out: | |
e6ea44e9 | 6793 | mutex_unlock(&ftrace_lock); |
3d083395 | 6794 | return ret; |
16444a8a | 6795 | } |