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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 | 64 | /* hash bits for specific function selection */ |
33dc9b12 SR |
65 | #define FTRACE_HASH_DEFAULT_BITS 10 |
66 | #define FTRACE_HASH_MAX_BITS 12 | |
8fc0c701 | 67 | |
f04f24fb | 68 | #ifdef CONFIG_DYNAMIC_FTRACE |
33b7f99c SRRH |
69 | #define INIT_OPS_HASH(opsname) \ |
70 | .func_hash = &opsname.local_hash, \ | |
71 | .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock), | |
f04f24fb | 72 | #else |
33b7f99c | 73 | #define INIT_OPS_HASH(opsname) |
f04f24fb MH |
74 | #endif |
75 | ||
a0572f68 SRV |
76 | enum { |
77 | FTRACE_MODIFY_ENABLE_FL = (1 << 0), | |
78 | FTRACE_MODIFY_MAY_SLEEP_FL = (1 << 1), | |
79 | }; | |
80 | ||
3306fc4a | 81 | struct ftrace_ops ftrace_list_end __read_mostly = { |
2f5f6ad9 | 82 | .func = ftrace_stub, |
395b97a3 | 83 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_STUB, |
33b7f99c | 84 | INIT_OPS_HASH(ftrace_list_end) |
2f5f6ad9 SR |
85 | }; |
86 | ||
4eebcc81 SR |
87 | /* ftrace_enabled is a method to turn ftrace on or off */ |
88 | int ftrace_enabled __read_mostly; | |
d61f82d0 | 89 | static int last_ftrace_enabled; |
b0fc494f | 90 | |
2f5f6ad9 SR |
91 | /* Current function tracing op */ |
92 | struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end; | |
405e1d83 SRRH |
93 | /* What to set function_trace_op to */ |
94 | static struct ftrace_ops *set_function_trace_op; | |
60a7ecf4 | 95 | |
345ddcc8 | 96 | static bool ftrace_pids_enabled(struct ftrace_ops *ops) |
e3eea140 | 97 | { |
345ddcc8 SRRH |
98 | struct trace_array *tr; |
99 | ||
100 | if (!(ops->flags & FTRACE_OPS_FL_PID) || !ops->private) | |
101 | return false; | |
102 | ||
103 | tr = ops->private; | |
104 | ||
b3b1e6ed | 105 | return tr->function_pids != NULL || tr->function_no_pids != NULL; |
e3eea140 SRRH |
106 | } |
107 | ||
108 | static void ftrace_update_trampoline(struct ftrace_ops *ops); | |
109 | ||
4eebcc81 SR |
110 | /* |
111 | * ftrace_disabled is set when an anomaly is discovered. | |
112 | * ftrace_disabled is much stronger than ftrace_enabled. | |
113 | */ | |
114 | static int ftrace_disabled __read_mostly; | |
115 | ||
3306fc4a | 116 | DEFINE_MUTEX(ftrace_lock); |
b0fc494f | 117 | |
3306fc4a | 118 | struct ftrace_ops __rcu *ftrace_ops_list __read_mostly = &ftrace_list_end; |
16444a8a | 119 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; |
3306fc4a | 120 | struct ftrace_ops global_ops; |
16444a8a | 121 | |
2f5f6ad9 SR |
122 | #if ARCH_SUPPORTS_FTRACE_OPS |
123 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 124 | struct ftrace_ops *op, struct pt_regs *regs); |
2f5f6ad9 SR |
125 | #else |
126 | /* See comment below, where ftrace_ops_list_func is defined */ | |
127 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip); | |
128 | #define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops) | |
129 | #endif | |
b848914c | 130 | |
f04f24fb MH |
131 | static inline void ftrace_ops_init(struct ftrace_ops *ops) |
132 | { | |
133 | #ifdef CONFIG_DYNAMIC_FTRACE | |
134 | if (!(ops->flags & FTRACE_OPS_FL_INITIALIZED)) { | |
33b7f99c SRRH |
135 | mutex_init(&ops->local_hash.regex_lock); |
136 | ops->func_hash = &ops->local_hash; | |
f04f24fb MH |
137 | ops->flags |= FTRACE_OPS_FL_INITIALIZED; |
138 | } | |
139 | #endif | |
140 | } | |
141 | ||
717e3f5e SRV |
142 | #define FTRACE_PID_IGNORE -1 |
143 | #define FTRACE_PID_TRACE -2 | |
144 | ||
2f5f6ad9 | 145 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 146 | struct ftrace_ops *op, struct pt_regs *regs) |
df4fc315 | 147 | { |
345ddcc8 | 148 | struct trace_array *tr = op->private; |
717e3f5e | 149 | int pid; |
345ddcc8 | 150 | |
717e3f5e SRV |
151 | if (tr) { |
152 | pid = this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid); | |
153 | if (pid == FTRACE_PID_IGNORE) | |
154 | return; | |
155 | if (pid != FTRACE_PID_TRACE && | |
156 | pid != current->pid) | |
157 | return; | |
158 | } | |
df4fc315 | 159 | |
e3eea140 | 160 | op->saved_func(ip, parent_ip, op, regs); |
df4fc315 SR |
161 | } |
162 | ||
405e1d83 SRRH |
163 | static void ftrace_sync_ipi(void *data) |
164 | { | |
165 | /* Probably not needed, but do it anyway */ | |
166 | smp_rmb(); | |
167 | } | |
168 | ||
00ccbf2f SRRH |
169 | static ftrace_func_t ftrace_ops_get_list_func(struct ftrace_ops *ops) |
170 | { | |
171 | /* | |
ba27f2bc | 172 | * If this is a dynamic, RCU, or per CPU ops, or we force list func, |
00ccbf2f SRRH |
173 | * then it needs to call the list anyway. |
174 | */ | |
b3a88803 PZ |
175 | if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_RCU) || |
176 | FTRACE_FORCE_LIST_FUNC) | |
00ccbf2f SRRH |
177 | return ftrace_ops_list_func; |
178 | ||
179 | return ftrace_ops_get_func(ops); | |
180 | } | |
181 | ||
2b499381 SR |
182 | static void update_ftrace_function(void) |
183 | { | |
184 | ftrace_func_t func; | |
185 | ||
f7aad4e1 SRRH |
186 | /* |
187 | * Prepare the ftrace_ops that the arch callback will use. | |
188 | * If there's only one ftrace_ops registered, the ftrace_ops_list | |
189 | * will point to the ops we want. | |
190 | */ | |
f86f4180 CZ |
191 | set_function_trace_op = rcu_dereference_protected(ftrace_ops_list, |
192 | lockdep_is_held(&ftrace_lock)); | |
f7aad4e1 SRRH |
193 | |
194 | /* If there's no ftrace_ops registered, just call the stub function */ | |
f86f4180 | 195 | if (set_function_trace_op == &ftrace_list_end) { |
f7aad4e1 SRRH |
196 | func = ftrace_stub; |
197 | ||
cdbe61bf SR |
198 | /* |
199 | * If we are at the end of the list and this ops is | |
4740974a SR |
200 | * recursion safe and not dynamic and the arch supports passing ops, |
201 | * then have the mcount trampoline call the function directly. | |
cdbe61bf | 202 | */ |
f86f4180 CZ |
203 | } else if (rcu_dereference_protected(ftrace_ops_list->next, |
204 | lockdep_is_held(&ftrace_lock)) == &ftrace_list_end) { | |
00ccbf2f | 205 | func = ftrace_ops_get_list_func(ftrace_ops_list); |
f7aad4e1 | 206 | |
2f5f6ad9 SR |
207 | } else { |
208 | /* Just use the default ftrace_ops */ | |
405e1d83 | 209 | set_function_trace_op = &ftrace_list_end; |
b848914c | 210 | func = ftrace_ops_list_func; |
2f5f6ad9 | 211 | } |
2b499381 | 212 | |
5f8bf2d2 SRRH |
213 | update_function_graph_func(); |
214 | ||
405e1d83 SRRH |
215 | /* If there's no change, then do nothing more here */ |
216 | if (ftrace_trace_function == func) | |
217 | return; | |
218 | ||
219 | /* | |
220 | * If we are using the list function, it doesn't care | |
221 | * about the function_trace_ops. | |
222 | */ | |
223 | if (func == ftrace_ops_list_func) { | |
224 | ftrace_trace_function = func; | |
225 | /* | |
226 | * Don't even bother setting function_trace_ops, | |
227 | * it would be racy to do so anyway. | |
228 | */ | |
229 | return; | |
230 | } | |
231 | ||
232 | #ifndef CONFIG_DYNAMIC_FTRACE | |
233 | /* | |
234 | * For static tracing, we need to be a bit more careful. | |
235 | * The function change takes affect immediately. Thus, | |
236 | * we need to coorditate the setting of the function_trace_ops | |
237 | * with the setting of the ftrace_trace_function. | |
238 | * | |
239 | * Set the function to the list ops, which will call the | |
240 | * function we want, albeit indirectly, but it handles the | |
241 | * ftrace_ops and doesn't depend on function_trace_op. | |
242 | */ | |
243 | ftrace_trace_function = ftrace_ops_list_func; | |
244 | /* | |
245 | * Make sure all CPUs see this. Yes this is slow, but static | |
246 | * tracing is slow and nasty to have enabled. | |
247 | */ | |
e5a971d7 | 248 | synchronize_rcu_tasks_rude(); |
405e1d83 SRRH |
249 | /* Now all cpus are using the list ops. */ |
250 | function_trace_op = set_function_trace_op; | |
251 | /* Make sure the function_trace_op is visible on all CPUs */ | |
252 | smp_wmb(); | |
253 | /* Nasty way to force a rmb on all cpus */ | |
254 | smp_call_function(ftrace_sync_ipi, NULL, 1); | |
255 | /* OK, we are all set to update the ftrace_trace_function now! */ | |
256 | #endif /* !CONFIG_DYNAMIC_FTRACE */ | |
257 | ||
491d0dcf | 258 | ftrace_trace_function = func; |
491d0dcf SR |
259 | } |
260 | ||
f86f4180 CZ |
261 | static void add_ftrace_ops(struct ftrace_ops __rcu **list, |
262 | struct ftrace_ops *ops) | |
3d083395 | 263 | { |
f86f4180 CZ |
264 | rcu_assign_pointer(ops->next, *list); |
265 | ||
16444a8a | 266 | /* |
b848914c | 267 | * We are entering ops into the list but another |
16444a8a ACM |
268 | * CPU might be walking that list. We need to make sure |
269 | * the ops->next pointer is valid before another CPU sees | |
b848914c | 270 | * the ops pointer included into the list. |
16444a8a | 271 | */ |
2b499381 | 272 | rcu_assign_pointer(*list, ops); |
16444a8a ACM |
273 | } |
274 | ||
f86f4180 CZ |
275 | static int remove_ftrace_ops(struct ftrace_ops __rcu **list, |
276 | struct ftrace_ops *ops) | |
16444a8a | 277 | { |
16444a8a | 278 | struct ftrace_ops **p; |
16444a8a ACM |
279 | |
280 | /* | |
3d083395 SR |
281 | * If we are removing the last function, then simply point |
282 | * to the ftrace_stub. | |
16444a8a | 283 | */ |
f86f4180 CZ |
284 | if (rcu_dereference_protected(*list, |
285 | lockdep_is_held(&ftrace_lock)) == ops && | |
286 | rcu_dereference_protected(ops->next, | |
287 | lockdep_is_held(&ftrace_lock)) == &ftrace_list_end) { | |
2b499381 | 288 | *list = &ftrace_list_end; |
e6ea44e9 | 289 | return 0; |
16444a8a ACM |
290 | } |
291 | ||
2b499381 | 292 | for (p = list; *p != &ftrace_list_end; p = &(*p)->next) |
16444a8a ACM |
293 | if (*p == ops) |
294 | break; | |
295 | ||
e6ea44e9 SR |
296 | if (*p != ops) |
297 | return -1; | |
16444a8a ACM |
298 | |
299 | *p = (*p)->next; | |
2b499381 SR |
300 | return 0; |
301 | } | |
16444a8a | 302 | |
f3bea491 SRRH |
303 | static void ftrace_update_trampoline(struct ftrace_ops *ops); |
304 | ||
3306fc4a | 305 | int __register_ftrace_function(struct ftrace_ops *ops) |
2b499381 | 306 | { |
591dffda SRRH |
307 | if (ops->flags & FTRACE_OPS_FL_DELETED) |
308 | return -EINVAL; | |
309 | ||
b848914c SR |
310 | if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED)) |
311 | return -EBUSY; | |
312 | ||
06aeaaea | 313 | #ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
08f6fba5 SR |
314 | /* |
315 | * If the ftrace_ops specifies SAVE_REGS, then it only can be used | |
316 | * if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set. | |
317 | * Setting SAVE_REGS_IF_SUPPORTED makes SAVE_REGS irrelevant. | |
318 | */ | |
319 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS && | |
320 | !(ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)) | |
321 | return -EINVAL; | |
322 | ||
323 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED) | |
324 | ops->flags |= FTRACE_OPS_FL_SAVE_REGS; | |
325 | #endif | |
7162431d MB |
326 | if (!ftrace_enabled && (ops->flags & FTRACE_OPS_FL_PERMANENT)) |
327 | return -EBUSY; | |
08f6fba5 | 328 | |
cdbe61bf SR |
329 | if (!core_kernel_data((unsigned long)ops)) |
330 | ops->flags |= FTRACE_OPS_FL_DYNAMIC; | |
331 | ||
ba27f2bc | 332 | add_ftrace_ops(&ftrace_ops_list, ops); |
b848914c | 333 | |
e3eea140 SRRH |
334 | /* Always save the function, and reset at unregistering */ |
335 | ops->saved_func = ops->func; | |
336 | ||
345ddcc8 | 337 | if (ftrace_pids_enabled(ops)) |
e3eea140 SRRH |
338 | ops->func = ftrace_pid_func; |
339 | ||
f3bea491 SRRH |
340 | ftrace_update_trampoline(ops); |
341 | ||
2b499381 SR |
342 | if (ftrace_enabled) |
343 | update_ftrace_function(); | |
344 | ||
345 | return 0; | |
346 | } | |
347 | ||
3306fc4a | 348 | int __unregister_ftrace_function(struct ftrace_ops *ops) |
2b499381 SR |
349 | { |
350 | int ret; | |
351 | ||
b848914c SR |
352 | if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) |
353 | return -EBUSY; | |
354 | ||
ba27f2bc | 355 | ret = remove_ftrace_ops(&ftrace_ops_list, ops); |
b848914c | 356 | |
2b499381 SR |
357 | if (ret < 0) |
358 | return ret; | |
b848914c | 359 | |
491d0dcf SR |
360 | if (ftrace_enabled) |
361 | update_ftrace_function(); | |
16444a8a | 362 | |
e3eea140 SRRH |
363 | ops->func = ops->saved_func; |
364 | ||
e6ea44e9 | 365 | return 0; |
3d083395 SR |
366 | } |
367 | ||
df4fc315 SR |
368 | static void ftrace_update_pid_func(void) |
369 | { | |
e3eea140 SRRH |
370 | struct ftrace_ops *op; |
371 | ||
491d0dcf | 372 | /* Only do something if we are tracing something */ |
df4fc315 | 373 | if (ftrace_trace_function == ftrace_stub) |
10dd3ebe | 374 | return; |
df4fc315 | 375 | |
e3eea140 SRRH |
376 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
377 | if (op->flags & FTRACE_OPS_FL_PID) { | |
345ddcc8 SRRH |
378 | op->func = ftrace_pids_enabled(op) ? |
379 | ftrace_pid_func : op->saved_func; | |
e3eea140 SRRH |
380 | ftrace_update_trampoline(op); |
381 | } | |
382 | } while_for_each_ftrace_op(op); | |
383 | ||
491d0dcf | 384 | update_ftrace_function(); |
df4fc315 SR |
385 | } |
386 | ||
493762fc SR |
387 | #ifdef CONFIG_FUNCTION_PROFILER |
388 | struct ftrace_profile { | |
389 | struct hlist_node node; | |
390 | unsigned long ip; | |
391 | unsigned long counter; | |
0706f1c4 SR |
392 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
393 | unsigned long long time; | |
e330b3bc | 394 | unsigned long long time_squared; |
0706f1c4 | 395 | #endif |
8fc0c701 SR |
396 | }; |
397 | ||
493762fc SR |
398 | struct ftrace_profile_page { |
399 | struct ftrace_profile_page *next; | |
400 | unsigned long index; | |
401 | struct ftrace_profile records[]; | |
d61f82d0 SR |
402 | }; |
403 | ||
cafb168a SR |
404 | struct ftrace_profile_stat { |
405 | atomic_t disabled; | |
406 | struct hlist_head *hash; | |
407 | struct ftrace_profile_page *pages; | |
408 | struct ftrace_profile_page *start; | |
409 | struct tracer_stat stat; | |
410 | }; | |
411 | ||
493762fc SR |
412 | #define PROFILE_RECORDS_SIZE \ |
413 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | |
5072c59f | 414 | |
493762fc SR |
415 | #define PROFILES_PER_PAGE \ |
416 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | |
3d083395 | 417 | |
fb9fb015 SR |
418 | static int ftrace_profile_enabled __read_mostly; |
419 | ||
420 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ | |
bac429f0 SR |
421 | static DEFINE_MUTEX(ftrace_profile_lock); |
422 | ||
cafb168a | 423 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); |
493762fc | 424 | |
20079ebe NK |
425 | #define FTRACE_PROFILE_HASH_BITS 10 |
426 | #define FTRACE_PROFILE_HASH_SIZE (1 << FTRACE_PROFILE_HASH_BITS) | |
493762fc | 427 | |
bac429f0 SR |
428 | static void * |
429 | function_stat_next(void *v, int idx) | |
430 | { | |
493762fc SR |
431 | struct ftrace_profile *rec = v; |
432 | struct ftrace_profile_page *pg; | |
bac429f0 | 433 | |
493762fc | 434 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
bac429f0 SR |
435 | |
436 | again: | |
0296e425 LZ |
437 | if (idx != 0) |
438 | rec++; | |
439 | ||
bac429f0 SR |
440 | if ((void *)rec >= (void *)&pg->records[pg->index]) { |
441 | pg = pg->next; | |
442 | if (!pg) | |
443 | return NULL; | |
444 | rec = &pg->records[0]; | |
493762fc SR |
445 | if (!rec->counter) |
446 | goto again; | |
bac429f0 SR |
447 | } |
448 | ||
bac429f0 SR |
449 | return rec; |
450 | } | |
451 | ||
452 | static void *function_stat_start(struct tracer_stat *trace) | |
453 | { | |
cafb168a SR |
454 | struct ftrace_profile_stat *stat = |
455 | container_of(trace, struct ftrace_profile_stat, stat); | |
456 | ||
457 | if (!stat || !stat->start) | |
458 | return NULL; | |
459 | ||
460 | return function_stat_next(&stat->start->records[0], 0); | |
bac429f0 SR |
461 | } |
462 | ||
0706f1c4 SR |
463 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
464 | /* function graph compares on total time */ | |
80042c8f | 465 | static int function_stat_cmp(const void *p1, const void *p2) |
0706f1c4 | 466 | { |
80042c8f AS |
467 | const struct ftrace_profile *a = p1; |
468 | const struct ftrace_profile *b = p2; | |
0706f1c4 SR |
469 | |
470 | if (a->time < b->time) | |
471 | return -1; | |
472 | if (a->time > b->time) | |
473 | return 1; | |
474 | else | |
475 | return 0; | |
476 | } | |
477 | #else | |
478 | /* not function graph compares against hits */ | |
80042c8f | 479 | static int function_stat_cmp(const void *p1, const void *p2) |
bac429f0 | 480 | { |
80042c8f AS |
481 | const struct ftrace_profile *a = p1; |
482 | const struct ftrace_profile *b = p2; | |
bac429f0 SR |
483 | |
484 | if (a->counter < b->counter) | |
485 | return -1; | |
486 | if (a->counter > b->counter) | |
487 | return 1; | |
488 | else | |
489 | return 0; | |
490 | } | |
0706f1c4 | 491 | #endif |
bac429f0 SR |
492 | |
493 | static int function_stat_headers(struct seq_file *m) | |
494 | { | |
0706f1c4 | 495 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
fa6f0cc7 RV |
496 | seq_puts(m, " Function " |
497 | "Hit Time Avg s^2\n" | |
498 | " -------- " | |
499 | "--- ---- --- ---\n"); | |
0706f1c4 | 500 | #else |
fa6f0cc7 RV |
501 | seq_puts(m, " Function Hit\n" |
502 | " -------- ---\n"); | |
0706f1c4 | 503 | #endif |
bac429f0 SR |
504 | return 0; |
505 | } | |
506 | ||
507 | static int function_stat_show(struct seq_file *m, void *v) | |
508 | { | |
493762fc | 509 | struct ftrace_profile *rec = v; |
bac429f0 | 510 | char str[KSYM_SYMBOL_LEN]; |
3aaba20f | 511 | int ret = 0; |
0706f1c4 | 512 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b SR |
513 | static struct trace_seq s; |
514 | unsigned long long avg; | |
e330b3bc | 515 | unsigned long long stddev; |
0706f1c4 | 516 | #endif |
3aaba20f LZ |
517 | mutex_lock(&ftrace_profile_lock); |
518 | ||
519 | /* we raced with function_profile_reset() */ | |
520 | if (unlikely(rec->counter == 0)) { | |
521 | ret = -EBUSY; | |
522 | goto out; | |
523 | } | |
bac429f0 | 524 | |
8e436ca0 | 525 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e31f7939 | 526 | avg = div64_ul(rec->time, rec->counter); |
8e436ca0 UT |
527 | if (tracing_thresh && (avg < tracing_thresh)) |
528 | goto out; | |
529 | #endif | |
530 | ||
bac429f0 | 531 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); |
0706f1c4 SR |
532 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); |
533 | ||
534 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
fa6f0cc7 | 535 | seq_puts(m, " "); |
34886c8b | 536 | |
e330b3bc CD |
537 | /* Sample standard deviation (s^2) */ |
538 | if (rec->counter <= 1) | |
539 | stddev = 0; | |
540 | else { | |
52d85d76 JL |
541 | /* |
542 | * Apply Welford's method: | |
543 | * s^2 = 1 / (n * (n-1)) * (n * \Sum (x_i)^2 - (\Sum x_i)^2) | |
544 | */ | |
545 | stddev = rec->counter * rec->time_squared - | |
546 | rec->time * rec->time; | |
547 | ||
e330b3bc CD |
548 | /* |
549 | * Divide only 1000 for ns^2 -> us^2 conversion. | |
550 | * trace_print_graph_duration will divide 1000 again. | |
551 | */ | |
e31f7939 WY |
552 | stddev = div64_ul(stddev, |
553 | rec->counter * (rec->counter - 1) * 1000); | |
e330b3bc CD |
554 | } |
555 | ||
34886c8b SR |
556 | trace_seq_init(&s); |
557 | trace_print_graph_duration(rec->time, &s); | |
558 | trace_seq_puts(&s, " "); | |
559 | trace_print_graph_duration(avg, &s); | |
e330b3bc CD |
560 | trace_seq_puts(&s, " "); |
561 | trace_print_graph_duration(stddev, &s); | |
0706f1c4 | 562 | trace_print_seq(m, &s); |
0706f1c4 SR |
563 | #endif |
564 | seq_putc(m, '\n'); | |
3aaba20f LZ |
565 | out: |
566 | mutex_unlock(&ftrace_profile_lock); | |
bac429f0 | 567 | |
3aaba20f | 568 | return ret; |
bac429f0 SR |
569 | } |
570 | ||
cafb168a | 571 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) |
bac429f0 | 572 | { |
493762fc | 573 | struct ftrace_profile_page *pg; |
bac429f0 | 574 | |
cafb168a | 575 | pg = stat->pages = stat->start; |
bac429f0 | 576 | |
493762fc SR |
577 | while (pg) { |
578 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | |
579 | pg->index = 0; | |
580 | pg = pg->next; | |
bac429f0 SR |
581 | } |
582 | ||
cafb168a | 583 | memset(stat->hash, 0, |
493762fc SR |
584 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); |
585 | } | |
bac429f0 | 586 | |
cafb168a | 587 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) |
493762fc SR |
588 | { |
589 | struct ftrace_profile_page *pg; | |
318e0a73 SR |
590 | int functions; |
591 | int pages; | |
493762fc | 592 | int i; |
bac429f0 | 593 | |
493762fc | 594 | /* If we already allocated, do nothing */ |
cafb168a | 595 | if (stat->pages) |
493762fc | 596 | return 0; |
bac429f0 | 597 | |
cafb168a SR |
598 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); |
599 | if (!stat->pages) | |
493762fc | 600 | return -ENOMEM; |
bac429f0 | 601 | |
318e0a73 SR |
602 | #ifdef CONFIG_DYNAMIC_FTRACE |
603 | functions = ftrace_update_tot_cnt; | |
604 | #else | |
605 | /* | |
606 | * We do not know the number of functions that exist because | |
607 | * dynamic tracing is what counts them. With past experience | |
608 | * we have around 20K functions. That should be more than enough. | |
609 | * It is highly unlikely we will execute every function in | |
610 | * the kernel. | |
611 | */ | |
612 | functions = 20000; | |
613 | #endif | |
614 | ||
cafb168a | 615 | pg = stat->start = stat->pages; |
bac429f0 | 616 | |
318e0a73 SR |
617 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); |
618 | ||
39e30cd1 | 619 | for (i = 1; i < pages; i++) { |
493762fc | 620 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
493762fc | 621 | if (!pg->next) |
318e0a73 | 622 | goto out_free; |
493762fc SR |
623 | pg = pg->next; |
624 | } | |
625 | ||
626 | return 0; | |
318e0a73 SR |
627 | |
628 | out_free: | |
629 | pg = stat->start; | |
630 | while (pg) { | |
631 | unsigned long tmp = (unsigned long)pg; | |
632 | ||
633 | pg = pg->next; | |
634 | free_page(tmp); | |
635 | } | |
636 | ||
318e0a73 SR |
637 | stat->pages = NULL; |
638 | stat->start = NULL; | |
639 | ||
640 | return -ENOMEM; | |
bac429f0 SR |
641 | } |
642 | ||
cafb168a | 643 | static int ftrace_profile_init_cpu(int cpu) |
bac429f0 | 644 | { |
cafb168a | 645 | struct ftrace_profile_stat *stat; |
493762fc | 646 | int size; |
bac429f0 | 647 | |
cafb168a SR |
648 | stat = &per_cpu(ftrace_profile_stats, cpu); |
649 | ||
650 | if (stat->hash) { | |
493762fc | 651 | /* If the profile is already created, simply reset it */ |
cafb168a | 652 | ftrace_profile_reset(stat); |
493762fc SR |
653 | return 0; |
654 | } | |
bac429f0 | 655 | |
493762fc SR |
656 | /* |
657 | * We are profiling all functions, but usually only a few thousand | |
658 | * functions are hit. We'll make a hash of 1024 items. | |
659 | */ | |
660 | size = FTRACE_PROFILE_HASH_SIZE; | |
bac429f0 | 661 | |
6396bb22 | 662 | stat->hash = kcalloc(size, sizeof(struct hlist_head), GFP_KERNEL); |
493762fc | 663 | |
cafb168a | 664 | if (!stat->hash) |
493762fc SR |
665 | return -ENOMEM; |
666 | ||
318e0a73 | 667 | /* Preallocate the function profiling pages */ |
cafb168a SR |
668 | if (ftrace_profile_pages_init(stat) < 0) { |
669 | kfree(stat->hash); | |
670 | stat->hash = NULL; | |
493762fc SR |
671 | return -ENOMEM; |
672 | } | |
673 | ||
674 | return 0; | |
bac429f0 SR |
675 | } |
676 | ||
cafb168a SR |
677 | static int ftrace_profile_init(void) |
678 | { | |
679 | int cpu; | |
680 | int ret = 0; | |
681 | ||
c4602c1c | 682 | for_each_possible_cpu(cpu) { |
cafb168a SR |
683 | ret = ftrace_profile_init_cpu(cpu); |
684 | if (ret) | |
685 | break; | |
686 | } | |
687 | ||
688 | return ret; | |
689 | } | |
690 | ||
493762fc | 691 | /* interrupts must be disabled */ |
cafb168a SR |
692 | static struct ftrace_profile * |
693 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) | |
bac429f0 | 694 | { |
493762fc | 695 | struct ftrace_profile *rec; |
bac429f0 | 696 | struct hlist_head *hhd; |
bac429f0 SR |
697 | unsigned long key; |
698 | ||
20079ebe | 699 | key = hash_long(ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 700 | hhd = &stat->hash[key]; |
bac429f0 SR |
701 | |
702 | if (hlist_empty(hhd)) | |
703 | return NULL; | |
704 | ||
1bb539ca | 705 | hlist_for_each_entry_rcu_notrace(rec, hhd, node) { |
bac429f0 | 706 | if (rec->ip == ip) |
493762fc SR |
707 | return rec; |
708 | } | |
709 | ||
710 | return NULL; | |
711 | } | |
712 | ||
cafb168a SR |
713 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, |
714 | struct ftrace_profile *rec) | |
493762fc SR |
715 | { |
716 | unsigned long key; | |
717 | ||
20079ebe | 718 | key = hash_long(rec->ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 719 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); |
493762fc SR |
720 | } |
721 | ||
318e0a73 SR |
722 | /* |
723 | * The memory is already allocated, this simply finds a new record to use. | |
724 | */ | |
493762fc | 725 | static struct ftrace_profile * |
318e0a73 | 726 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) |
493762fc SR |
727 | { |
728 | struct ftrace_profile *rec = NULL; | |
729 | ||
318e0a73 | 730 | /* prevent recursion (from NMIs) */ |
cafb168a | 731 | if (atomic_inc_return(&stat->disabled) != 1) |
493762fc SR |
732 | goto out; |
733 | ||
493762fc | 734 | /* |
318e0a73 SR |
735 | * Try to find the function again since an NMI |
736 | * could have added it | |
493762fc | 737 | */ |
cafb168a | 738 | rec = ftrace_find_profiled_func(stat, ip); |
493762fc | 739 | if (rec) |
cafb168a | 740 | goto out; |
493762fc | 741 | |
cafb168a SR |
742 | if (stat->pages->index == PROFILES_PER_PAGE) { |
743 | if (!stat->pages->next) | |
744 | goto out; | |
745 | stat->pages = stat->pages->next; | |
bac429f0 | 746 | } |
493762fc | 747 | |
cafb168a | 748 | rec = &stat->pages->records[stat->pages->index++]; |
493762fc | 749 | rec->ip = ip; |
cafb168a | 750 | ftrace_add_profile(stat, rec); |
493762fc | 751 | |
bac429f0 | 752 | out: |
cafb168a | 753 | atomic_dec(&stat->disabled); |
bac429f0 SR |
754 | |
755 | return rec; | |
756 | } | |
757 | ||
758 | static void | |
2f5f6ad9 | 759 | function_profile_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 760 | struct ftrace_ops *ops, struct pt_regs *regs) |
bac429f0 | 761 | { |
cafb168a | 762 | struct ftrace_profile_stat *stat; |
493762fc | 763 | struct ftrace_profile *rec; |
bac429f0 SR |
764 | unsigned long flags; |
765 | ||
766 | if (!ftrace_profile_enabled) | |
767 | return; | |
768 | ||
769 | local_irq_save(flags); | |
cafb168a | 770 | |
bdffd893 | 771 | stat = this_cpu_ptr(&ftrace_profile_stats); |
0f6ce3de | 772 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
773 | goto out; |
774 | ||
775 | rec = ftrace_find_profiled_func(stat, ip); | |
493762fc | 776 | if (!rec) { |
318e0a73 | 777 | rec = ftrace_profile_alloc(stat, ip); |
493762fc SR |
778 | if (!rec) |
779 | goto out; | |
780 | } | |
bac429f0 SR |
781 | |
782 | rec->counter++; | |
783 | out: | |
784 | local_irq_restore(flags); | |
785 | } | |
786 | ||
0706f1c4 | 787 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e73e679f SRV |
788 | static bool fgraph_graph_time = true; |
789 | ||
790 | void ftrace_graph_graph_time_control(bool enable) | |
791 | { | |
792 | fgraph_graph_time = enable; | |
793 | } | |
794 | ||
0706f1c4 SR |
795 | static int profile_graph_entry(struct ftrace_graph_ent *trace) |
796 | { | |
b0e21a61 | 797 | struct ftrace_ret_stack *ret_stack; |
8861dd30 | 798 | |
a1e2e31d | 799 | function_profile_call(trace->func, 0, NULL, NULL); |
8861dd30 | 800 | |
a8f0f9e4 SRV |
801 | /* If function graph is shutting down, ret_stack can be NULL */ |
802 | if (!current->ret_stack) | |
803 | return 0; | |
804 | ||
b0e21a61 SRV |
805 | ret_stack = ftrace_graph_get_ret_stack(current, 0); |
806 | if (ret_stack) | |
807 | ret_stack->subtime = 0; | |
8861dd30 | 808 | |
0706f1c4 SR |
809 | return 1; |
810 | } | |
811 | ||
812 | static void profile_graph_return(struct ftrace_graph_ret *trace) | |
813 | { | |
b0e21a61 | 814 | struct ftrace_ret_stack *ret_stack; |
cafb168a | 815 | struct ftrace_profile_stat *stat; |
a2a16d6a | 816 | unsigned long long calltime; |
0706f1c4 | 817 | struct ftrace_profile *rec; |
cafb168a | 818 | unsigned long flags; |
0706f1c4 SR |
819 | |
820 | local_irq_save(flags); | |
bdffd893 | 821 | stat = this_cpu_ptr(&ftrace_profile_stats); |
0f6ce3de | 822 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
823 | goto out; |
824 | ||
37e44bc5 SR |
825 | /* If the calltime was zero'd ignore it */ |
826 | if (!trace->calltime) | |
827 | goto out; | |
828 | ||
a2a16d6a SR |
829 | calltime = trace->rettime - trace->calltime; |
830 | ||
55577204 | 831 | if (!fgraph_graph_time) { |
a2a16d6a SR |
832 | |
833 | /* Append this call time to the parent time to subtract */ | |
b0e21a61 SRV |
834 | ret_stack = ftrace_graph_get_ret_stack(current, 1); |
835 | if (ret_stack) | |
836 | ret_stack->subtime += calltime; | |
a2a16d6a | 837 | |
b0e21a61 SRV |
838 | ret_stack = ftrace_graph_get_ret_stack(current, 0); |
839 | if (ret_stack && ret_stack->subtime < calltime) | |
840 | calltime -= ret_stack->subtime; | |
a2a16d6a SR |
841 | else |
842 | calltime = 0; | |
843 | } | |
844 | ||
cafb168a | 845 | rec = ftrace_find_profiled_func(stat, trace->func); |
e330b3bc | 846 | if (rec) { |
a2a16d6a | 847 | rec->time += calltime; |
e330b3bc CD |
848 | rec->time_squared += calltime * calltime; |
849 | } | |
a2a16d6a | 850 | |
cafb168a | 851 | out: |
0706f1c4 SR |
852 | local_irq_restore(flags); |
853 | } | |
854 | ||
688f7089 SRV |
855 | static struct fgraph_ops fprofiler_ops = { |
856 | .entryfunc = &profile_graph_entry, | |
857 | .retfunc = &profile_graph_return, | |
858 | }; | |
859 | ||
0706f1c4 SR |
860 | static int register_ftrace_profiler(void) |
861 | { | |
688f7089 | 862 | return register_ftrace_graph(&fprofiler_ops); |
0706f1c4 SR |
863 | } |
864 | ||
865 | static void unregister_ftrace_profiler(void) | |
866 | { | |
688f7089 | 867 | unregister_ftrace_graph(&fprofiler_ops); |
0706f1c4 SR |
868 | } |
869 | #else | |
bd38c0e6 | 870 | static struct ftrace_ops ftrace_profile_ops __read_mostly = { |
fb9fb015 | 871 | .func = function_profile_call, |
f04f24fb | 872 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, |
33b7f99c | 873 | INIT_OPS_HASH(ftrace_profile_ops) |
bac429f0 SR |
874 | }; |
875 | ||
0706f1c4 SR |
876 | static int register_ftrace_profiler(void) |
877 | { | |
878 | return register_ftrace_function(&ftrace_profile_ops); | |
879 | } | |
880 | ||
881 | static void unregister_ftrace_profiler(void) | |
882 | { | |
883 | unregister_ftrace_function(&ftrace_profile_ops); | |
884 | } | |
885 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
886 | ||
bac429f0 SR |
887 | static ssize_t |
888 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | |
889 | size_t cnt, loff_t *ppos) | |
890 | { | |
891 | unsigned long val; | |
bac429f0 SR |
892 | int ret; |
893 | ||
22fe9b54 PH |
894 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
895 | if (ret) | |
bac429f0 SR |
896 | return ret; |
897 | ||
898 | val = !!val; | |
899 | ||
900 | mutex_lock(&ftrace_profile_lock); | |
901 | if (ftrace_profile_enabled ^ val) { | |
902 | if (val) { | |
493762fc SR |
903 | ret = ftrace_profile_init(); |
904 | if (ret < 0) { | |
905 | cnt = ret; | |
906 | goto out; | |
907 | } | |
908 | ||
0706f1c4 SR |
909 | ret = register_ftrace_profiler(); |
910 | if (ret < 0) { | |
911 | cnt = ret; | |
912 | goto out; | |
913 | } | |
bac429f0 SR |
914 | ftrace_profile_enabled = 1; |
915 | } else { | |
916 | ftrace_profile_enabled = 0; | |
0f6ce3de SR |
917 | /* |
918 | * unregister_ftrace_profiler calls stop_machine | |
74401729 | 919 | * so this acts like an synchronize_rcu. |
0f6ce3de | 920 | */ |
0706f1c4 | 921 | unregister_ftrace_profiler(); |
bac429f0 SR |
922 | } |
923 | } | |
493762fc | 924 | out: |
bac429f0 SR |
925 | mutex_unlock(&ftrace_profile_lock); |
926 | ||
cf8517cf | 927 | *ppos += cnt; |
bac429f0 SR |
928 | |
929 | return cnt; | |
930 | } | |
931 | ||
493762fc SR |
932 | static ssize_t |
933 | ftrace_profile_read(struct file *filp, char __user *ubuf, | |
934 | size_t cnt, loff_t *ppos) | |
935 | { | |
fb9fb015 | 936 | char buf[64]; /* big enough to hold a number */ |
493762fc SR |
937 | int r; |
938 | ||
939 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | |
940 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
941 | } | |
942 | ||
bac429f0 SR |
943 | static const struct file_operations ftrace_profile_fops = { |
944 | .open = tracing_open_generic, | |
945 | .read = ftrace_profile_read, | |
946 | .write = ftrace_profile_write, | |
6038f373 | 947 | .llseek = default_llseek, |
bac429f0 SR |
948 | }; |
949 | ||
cafb168a SR |
950 | /* used to initialize the real stat files */ |
951 | static struct tracer_stat function_stats __initdata = { | |
fb9fb015 SR |
952 | .name = "functions", |
953 | .stat_start = function_stat_start, | |
954 | .stat_next = function_stat_next, | |
955 | .stat_cmp = function_stat_cmp, | |
956 | .stat_headers = function_stat_headers, | |
957 | .stat_show = function_stat_show | |
cafb168a SR |
958 | }; |
959 | ||
8434dc93 | 960 | static __init void ftrace_profile_tracefs(struct dentry *d_tracer) |
bac429f0 | 961 | { |
cafb168a | 962 | struct ftrace_profile_stat *stat; |
bac429f0 | 963 | struct dentry *entry; |
cafb168a | 964 | char *name; |
bac429f0 | 965 | int ret; |
cafb168a SR |
966 | int cpu; |
967 | ||
968 | for_each_possible_cpu(cpu) { | |
969 | stat = &per_cpu(ftrace_profile_stats, cpu); | |
970 | ||
6363c6b5 | 971 | name = kasprintf(GFP_KERNEL, "function%d", cpu); |
cafb168a SR |
972 | if (!name) { |
973 | /* | |
974 | * The files created are permanent, if something happens | |
975 | * we still do not free memory. | |
976 | */ | |
cafb168a SR |
977 | WARN(1, |
978 | "Could not allocate stat file for cpu %d\n", | |
979 | cpu); | |
980 | return; | |
981 | } | |
982 | stat->stat = function_stats; | |
cafb168a SR |
983 | stat->stat.name = name; |
984 | ret = register_stat_tracer(&stat->stat); | |
985 | if (ret) { | |
986 | WARN(1, | |
987 | "Could not register function stat for cpu %d\n", | |
988 | cpu); | |
989 | kfree(name); | |
990 | return; | |
991 | } | |
bac429f0 SR |
992 | } |
993 | ||
8434dc93 | 994 | entry = tracefs_create_file("function_profile_enabled", 0644, |
bac429f0 SR |
995 | d_tracer, NULL, &ftrace_profile_fops); |
996 | if (!entry) | |
a395d6a7 | 997 | pr_warn("Could not create tracefs 'function_profile_enabled' entry\n"); |
bac429f0 SR |
998 | } |
999 | ||
bac429f0 | 1000 | #else /* CONFIG_FUNCTION_PROFILER */ |
8434dc93 | 1001 | static __init void ftrace_profile_tracefs(struct dentry *d_tracer) |
bac429f0 SR |
1002 | { |
1003 | } | |
bac429f0 SR |
1004 | #endif /* CONFIG_FUNCTION_PROFILER */ |
1005 | ||
493762fc SR |
1006 | #ifdef CONFIG_DYNAMIC_FTRACE |
1007 | ||
79922b80 SRRH |
1008 | static struct ftrace_ops *removed_ops; |
1009 | ||
e1effa01 SRRH |
1010 | /* |
1011 | * Set when doing a global update, like enabling all recs or disabling them. | |
1012 | * It is not set when just updating a single ftrace_ops. | |
1013 | */ | |
1014 | static bool update_all_ops; | |
1015 | ||
493762fc SR |
1016 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD |
1017 | # error Dynamic ftrace depends on MCOUNT_RECORD | |
1018 | #endif | |
1019 | ||
7b60f3d8 SRV |
1020 | struct ftrace_func_probe { |
1021 | struct ftrace_probe_ops *probe_ops; | |
1022 | struct ftrace_ops ops; | |
1023 | struct trace_array *tr; | |
1024 | struct list_head list; | |
6e444319 | 1025 | void *data; |
7b60f3d8 SRV |
1026 | int ref; |
1027 | }; | |
1028 | ||
33dc9b12 SR |
1029 | /* |
1030 | * We make these constant because no one should touch them, | |
1031 | * but they are used as the default "empty hash", to avoid allocating | |
1032 | * it all the time. These are in a read only section such that if | |
1033 | * anyone does try to modify it, it will cause an exception. | |
1034 | */ | |
1035 | static const struct hlist_head empty_buckets[1]; | |
1036 | static const struct ftrace_hash empty_hash = { | |
1037 | .buckets = (struct hlist_head *)empty_buckets, | |
1cf41dd7 | 1038 | }; |
33dc9b12 | 1039 | #define EMPTY_HASH ((struct ftrace_hash *)&empty_hash) |
493762fc | 1040 | |
3306fc4a | 1041 | struct ftrace_ops global_ops = { |
33b7f99c SRRH |
1042 | .func = ftrace_stub, |
1043 | .local_hash.notrace_hash = EMPTY_HASH, | |
1044 | .local_hash.filter_hash = EMPTY_HASH, | |
1045 | INIT_OPS_HASH(global_ops) | |
1046 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | | |
e3eea140 SRRH |
1047 | FTRACE_OPS_FL_INITIALIZED | |
1048 | FTRACE_OPS_FL_PID, | |
f45948e8 SR |
1049 | }; |
1050 | ||
aec0be2d | 1051 | /* |
6be7fa3c | 1052 | * Used by the stack undwinder to know about dynamic ftrace trampolines. |
aec0be2d | 1053 | */ |
6be7fa3c | 1054 | struct ftrace_ops *ftrace_ops_trampoline(unsigned long addr) |
aec0be2d | 1055 | { |
6be7fa3c | 1056 | struct ftrace_ops *op = NULL; |
aec0be2d SRRH |
1057 | |
1058 | /* | |
1059 | * Some of the ops may be dynamically allocated, | |
74401729 | 1060 | * they are freed after a synchronize_rcu(). |
aec0be2d SRRH |
1061 | */ |
1062 | preempt_disable_notrace(); | |
1063 | ||
1064 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
1065 | /* | |
1066 | * This is to check for dynamically allocated trampolines. | |
1067 | * Trampolines that are in kernel text will have | |
1068 | * core_kernel_text() return true. | |
1069 | */ | |
1070 | if (op->trampoline && op->trampoline_size) | |
1071 | if (addr >= op->trampoline && | |
1072 | addr < op->trampoline + op->trampoline_size) { | |
6be7fa3c SRV |
1073 | preempt_enable_notrace(); |
1074 | return op; | |
aec0be2d SRRH |
1075 | } |
1076 | } while_for_each_ftrace_op(op); | |
aec0be2d SRRH |
1077 | preempt_enable_notrace(); |
1078 | ||
6be7fa3c SRV |
1079 | return NULL; |
1080 | } | |
1081 | ||
1082 | /* | |
1083 | * This is used by __kernel_text_address() to return true if the | |
1084 | * address is on a dynamically allocated trampoline that would | |
1085 | * not return true for either core_kernel_text() or | |
1086 | * is_module_text_address(). | |
1087 | */ | |
1088 | bool is_ftrace_trampoline(unsigned long addr) | |
1089 | { | |
1090 | return ftrace_ops_trampoline(addr) != NULL; | |
aec0be2d SRRH |
1091 | } |
1092 | ||
493762fc SR |
1093 | struct ftrace_page { |
1094 | struct ftrace_page *next; | |
a7900875 | 1095 | struct dyn_ftrace *records; |
493762fc | 1096 | int index; |
a7900875 | 1097 | int size; |
493762fc SR |
1098 | }; |
1099 | ||
a7900875 SR |
1100 | #define ENTRY_SIZE sizeof(struct dyn_ftrace) |
1101 | #define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE) | |
493762fc | 1102 | |
493762fc SR |
1103 | static struct ftrace_page *ftrace_pages_start; |
1104 | static struct ftrace_page *ftrace_pages; | |
1105 | ||
2b0cce0e SRV |
1106 | static __always_inline unsigned long |
1107 | ftrace_hash_key(struct ftrace_hash *hash, unsigned long ip) | |
1108 | { | |
1109 | if (hash->size_bits > 0) | |
1110 | return hash_long(ip, hash->size_bits); | |
1111 | ||
1112 | return 0; | |
1113 | } | |
1114 | ||
2b2c279c SRV |
1115 | /* Only use this function if ftrace_hash_empty() has already been tested */ |
1116 | static __always_inline struct ftrace_func_entry * | |
1117 | __ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
b448c4e3 SR |
1118 | { |
1119 | unsigned long key; | |
1120 | struct ftrace_func_entry *entry; | |
1121 | struct hlist_head *hhd; | |
b448c4e3 | 1122 | |
2b0cce0e | 1123 | key = ftrace_hash_key(hash, ip); |
b448c4e3 SR |
1124 | hhd = &hash->buckets[key]; |
1125 | ||
1bb539ca | 1126 | hlist_for_each_entry_rcu_notrace(entry, hhd, hlist) { |
b448c4e3 SR |
1127 | if (entry->ip == ip) |
1128 | return entry; | |
1129 | } | |
1130 | return NULL; | |
1131 | } | |
1132 | ||
2b2c279c SRV |
1133 | /** |
1134 | * ftrace_lookup_ip - Test to see if an ip exists in an ftrace_hash | |
1135 | * @hash: The hash to look at | |
1136 | * @ip: The instruction pointer to test | |
1137 | * | |
1138 | * Search a given @hash to see if a given instruction pointer (@ip) | |
1139 | * exists in it. | |
1140 | * | |
1141 | * Returns the entry that holds the @ip if found. NULL otherwise. | |
1142 | */ | |
1143 | struct ftrace_func_entry * | |
1144 | ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
1145 | { | |
1146 | if (ftrace_hash_empty(hash)) | |
1147 | return NULL; | |
1148 | ||
1149 | return __ftrace_lookup_ip(hash, ip); | |
1150 | } | |
1151 | ||
33dc9b12 SR |
1152 | static void __add_hash_entry(struct ftrace_hash *hash, |
1153 | struct ftrace_func_entry *entry) | |
b448c4e3 | 1154 | { |
b448c4e3 SR |
1155 | struct hlist_head *hhd; |
1156 | unsigned long key; | |
1157 | ||
2b0cce0e | 1158 | key = ftrace_hash_key(hash, entry->ip); |
b448c4e3 SR |
1159 | hhd = &hash->buckets[key]; |
1160 | hlist_add_head(&entry->hlist, hhd); | |
1161 | hash->count++; | |
33dc9b12 SR |
1162 | } |
1163 | ||
1164 | static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) | |
1165 | { | |
1166 | struct ftrace_func_entry *entry; | |
1167 | ||
1168 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
1169 | if (!entry) | |
1170 | return -ENOMEM; | |
1171 | ||
1172 | entry->ip = ip; | |
1173 | __add_hash_entry(hash, entry); | |
b448c4e3 SR |
1174 | |
1175 | return 0; | |
1176 | } | |
1177 | ||
1178 | static void | |
33dc9b12 | 1179 | free_hash_entry(struct ftrace_hash *hash, |
b448c4e3 SR |
1180 | struct ftrace_func_entry *entry) |
1181 | { | |
1182 | hlist_del(&entry->hlist); | |
1183 | kfree(entry); | |
1184 | hash->count--; | |
1185 | } | |
1186 | ||
33dc9b12 SR |
1187 | static void |
1188 | remove_hash_entry(struct ftrace_hash *hash, | |
1189 | struct ftrace_func_entry *entry) | |
1190 | { | |
eee8ded1 | 1191 | hlist_del_rcu(&entry->hlist); |
33dc9b12 SR |
1192 | hash->count--; |
1193 | } | |
1194 | ||
b448c4e3 SR |
1195 | static void ftrace_hash_clear(struct ftrace_hash *hash) |
1196 | { | |
1197 | struct hlist_head *hhd; | |
b67bfe0d | 1198 | struct hlist_node *tn; |
b448c4e3 SR |
1199 | struct ftrace_func_entry *entry; |
1200 | int size = 1 << hash->size_bits; | |
1201 | int i; | |
1202 | ||
33dc9b12 SR |
1203 | if (!hash->count) |
1204 | return; | |
1205 | ||
b448c4e3 SR |
1206 | for (i = 0; i < size; i++) { |
1207 | hhd = &hash->buckets[i]; | |
b67bfe0d | 1208 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) |
33dc9b12 | 1209 | free_hash_entry(hash, entry); |
b448c4e3 SR |
1210 | } |
1211 | FTRACE_WARN_ON(hash->count); | |
1212 | } | |
1213 | ||
673feb9d SRV |
1214 | static void free_ftrace_mod(struct ftrace_mod_load *ftrace_mod) |
1215 | { | |
1216 | list_del(&ftrace_mod->list); | |
1217 | kfree(ftrace_mod->module); | |
1218 | kfree(ftrace_mod->func); | |
1219 | kfree(ftrace_mod); | |
1220 | } | |
1221 | ||
1222 | static void clear_ftrace_mod_list(struct list_head *head) | |
1223 | { | |
1224 | struct ftrace_mod_load *p, *n; | |
1225 | ||
1226 | /* stack tracer isn't supported yet */ | |
1227 | if (!head) | |
1228 | return; | |
1229 | ||
1230 | mutex_lock(&ftrace_lock); | |
1231 | list_for_each_entry_safe(p, n, head, list) | |
1232 | free_ftrace_mod(p); | |
1233 | mutex_unlock(&ftrace_lock); | |
1234 | } | |
1235 | ||
33dc9b12 SR |
1236 | static void free_ftrace_hash(struct ftrace_hash *hash) |
1237 | { | |
1238 | if (!hash || hash == EMPTY_HASH) | |
1239 | return; | |
1240 | ftrace_hash_clear(hash); | |
1241 | kfree(hash->buckets); | |
1242 | kfree(hash); | |
1243 | } | |
1244 | ||
07fd5515 SR |
1245 | static void __free_ftrace_hash_rcu(struct rcu_head *rcu) |
1246 | { | |
1247 | struct ftrace_hash *hash; | |
1248 | ||
1249 | hash = container_of(rcu, struct ftrace_hash, rcu); | |
1250 | free_ftrace_hash(hash); | |
1251 | } | |
1252 | ||
1253 | static void free_ftrace_hash_rcu(struct ftrace_hash *hash) | |
1254 | { | |
1255 | if (!hash || hash == EMPTY_HASH) | |
1256 | return; | |
74401729 | 1257 | call_rcu(&hash->rcu, __free_ftrace_hash_rcu); |
07fd5515 SR |
1258 | } |
1259 | ||
5500fa51 JO |
1260 | void ftrace_free_filter(struct ftrace_ops *ops) |
1261 | { | |
f04f24fb | 1262 | ftrace_ops_init(ops); |
33b7f99c SRRH |
1263 | free_ftrace_hash(ops->func_hash->filter_hash); |
1264 | free_ftrace_hash(ops->func_hash->notrace_hash); | |
5500fa51 JO |
1265 | } |
1266 | ||
33dc9b12 SR |
1267 | static struct ftrace_hash *alloc_ftrace_hash(int size_bits) |
1268 | { | |
1269 | struct ftrace_hash *hash; | |
1270 | int size; | |
1271 | ||
1272 | hash = kzalloc(sizeof(*hash), GFP_KERNEL); | |
1273 | if (!hash) | |
1274 | return NULL; | |
1275 | ||
1276 | size = 1 << size_bits; | |
47b0edcb | 1277 | hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL); |
33dc9b12 SR |
1278 | |
1279 | if (!hash->buckets) { | |
1280 | kfree(hash); | |
1281 | return NULL; | |
1282 | } | |
1283 | ||
1284 | hash->size_bits = size_bits; | |
1285 | ||
1286 | return hash; | |
1287 | } | |
1288 | ||
673feb9d SRV |
1289 | |
1290 | static int ftrace_add_mod(struct trace_array *tr, | |
1291 | const char *func, const char *module, | |
1292 | int enable) | |
1293 | { | |
1294 | struct ftrace_mod_load *ftrace_mod; | |
1295 | struct list_head *mod_head = enable ? &tr->mod_trace : &tr->mod_notrace; | |
1296 | ||
1297 | ftrace_mod = kzalloc(sizeof(*ftrace_mod), GFP_KERNEL); | |
1298 | if (!ftrace_mod) | |
1299 | return -ENOMEM; | |
1300 | ||
1301 | ftrace_mod->func = kstrdup(func, GFP_KERNEL); | |
1302 | ftrace_mod->module = kstrdup(module, GFP_KERNEL); | |
1303 | ftrace_mod->enable = enable; | |
1304 | ||
1305 | if (!ftrace_mod->func || !ftrace_mod->module) | |
1306 | goto out_free; | |
1307 | ||
1308 | list_add(&ftrace_mod->list, mod_head); | |
1309 | ||
1310 | return 0; | |
1311 | ||
1312 | out_free: | |
1313 | free_ftrace_mod(ftrace_mod); | |
1314 | ||
1315 | return -ENOMEM; | |
1316 | } | |
1317 | ||
33dc9b12 SR |
1318 | static struct ftrace_hash * |
1319 | alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) | |
1320 | { | |
1321 | struct ftrace_func_entry *entry; | |
1322 | struct ftrace_hash *new_hash; | |
33dc9b12 SR |
1323 | int size; |
1324 | int ret; | |
1325 | int i; | |
1326 | ||
1327 | new_hash = alloc_ftrace_hash(size_bits); | |
1328 | if (!new_hash) | |
1329 | return NULL; | |
1330 | ||
8c08f0d5 SRV |
1331 | if (hash) |
1332 | new_hash->flags = hash->flags; | |
1333 | ||
33dc9b12 | 1334 | /* Empty hash? */ |
06a51d93 | 1335 | if (ftrace_hash_empty(hash)) |
33dc9b12 SR |
1336 | return new_hash; |
1337 | ||
1338 | size = 1 << hash->size_bits; | |
1339 | for (i = 0; i < size; i++) { | |
b67bfe0d | 1340 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { |
33dc9b12 SR |
1341 | ret = add_hash_entry(new_hash, entry->ip); |
1342 | if (ret < 0) | |
1343 | goto free_hash; | |
1344 | } | |
1345 | } | |
1346 | ||
1347 | FTRACE_WARN_ON(new_hash->count != hash->count); | |
1348 | ||
1349 | return new_hash; | |
1350 | ||
1351 | free_hash: | |
1352 | free_ftrace_hash(new_hash); | |
1353 | return NULL; | |
1354 | } | |
1355 | ||
41fb61c2 | 1356 | static void |
84261912 | 1357 | ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, int filter_hash); |
41fb61c2 | 1358 | static void |
84261912 | 1359 | ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, int filter_hash); |
41fb61c2 | 1360 | |
f8b8be8a MH |
1361 | static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops, |
1362 | struct ftrace_hash *new_hash); | |
1363 | ||
714641c3 | 1364 | static struct ftrace_hash *dup_hash(struct ftrace_hash *src, int size) |
33dc9b12 SR |
1365 | { |
1366 | struct ftrace_func_entry *entry; | |
07fd5515 | 1367 | struct ftrace_hash *new_hash; |
714641c3 SRV |
1368 | struct hlist_head *hhd; |
1369 | struct hlist_node *tn; | |
33dc9b12 SR |
1370 | int bits = 0; |
1371 | int i; | |
1372 | ||
33dc9b12 SR |
1373 | /* |
1374 | * Make the hash size about 1/2 the # found | |
1375 | */ | |
1376 | for (size /= 2; size; size >>= 1) | |
1377 | bits++; | |
1378 | ||
1379 | /* Don't allocate too much */ | |
1380 | if (bits > FTRACE_HASH_MAX_BITS) | |
1381 | bits = FTRACE_HASH_MAX_BITS; | |
1382 | ||
07fd5515 SR |
1383 | new_hash = alloc_ftrace_hash(bits); |
1384 | if (!new_hash) | |
3e278c0d | 1385 | return NULL; |
33dc9b12 | 1386 | |
8c08f0d5 SRV |
1387 | new_hash->flags = src->flags; |
1388 | ||
33dc9b12 SR |
1389 | size = 1 << src->size_bits; |
1390 | for (i = 0; i < size; i++) { | |
1391 | hhd = &src->buckets[i]; | |
b67bfe0d | 1392 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) { |
33dc9b12 | 1393 | remove_hash_entry(src, entry); |
07fd5515 | 1394 | __add_hash_entry(new_hash, entry); |
33dc9b12 SR |
1395 | } |
1396 | } | |
3e278c0d NK |
1397 | return new_hash; |
1398 | } | |
1399 | ||
714641c3 SRV |
1400 | static struct ftrace_hash * |
1401 | __ftrace_hash_move(struct ftrace_hash *src) | |
1402 | { | |
1403 | int size = src->count; | |
1404 | ||
1405 | /* | |
1406 | * If the new source is empty, just return the empty_hash. | |
1407 | */ | |
1408 | if (ftrace_hash_empty(src)) | |
1409 | return EMPTY_HASH; | |
1410 | ||
1411 | return dup_hash(src, size); | |
1412 | } | |
1413 | ||
3e278c0d NK |
1414 | static int |
1415 | ftrace_hash_move(struct ftrace_ops *ops, int enable, | |
1416 | struct ftrace_hash **dst, struct ftrace_hash *src) | |
1417 | { | |
1418 | struct ftrace_hash *new_hash; | |
1419 | int ret; | |
1420 | ||
1421 | /* Reject setting notrace hash on IPMODIFY ftrace_ops */ | |
1422 | if (ops->flags & FTRACE_OPS_FL_IPMODIFY && !enable) | |
1423 | return -EINVAL; | |
1424 | ||
1425 | new_hash = __ftrace_hash_move(src); | |
1426 | if (!new_hash) | |
1427 | return -ENOMEM; | |
1428 | ||
f8b8be8a MH |
1429 | /* Make sure this can be applied if it is IPMODIFY ftrace_ops */ |
1430 | if (enable) { | |
1431 | /* IPMODIFY should be updated only when filter_hash updating */ | |
1432 | ret = ftrace_hash_ipmodify_update(ops, new_hash); | |
1433 | if (ret < 0) { | |
1434 | free_ftrace_hash(new_hash); | |
1435 | return ret; | |
1436 | } | |
1437 | } | |
1438 | ||
5c27c775 MH |
1439 | /* |
1440 | * Remove the current set, update the hash and add | |
1441 | * them back. | |
1442 | */ | |
84261912 | 1443 | ftrace_hash_rec_disable_modify(ops, enable); |
5c27c775 | 1444 | |
07fd5515 | 1445 | rcu_assign_pointer(*dst, new_hash); |
07fd5515 | 1446 | |
84261912 | 1447 | ftrace_hash_rec_enable_modify(ops, enable); |
41fb61c2 | 1448 | |
5c27c775 | 1449 | return 0; |
33dc9b12 SR |
1450 | } |
1451 | ||
fef5aeee SRRH |
1452 | static bool hash_contains_ip(unsigned long ip, |
1453 | struct ftrace_ops_hash *hash) | |
1454 | { | |
1455 | /* | |
1456 | * The function record is a match if it exists in the filter | |
1457 | * hash and not in the notrace hash. Note, an emty hash is | |
1458 | * considered a match for the filter hash, but an empty | |
1459 | * notrace hash is considered not in the notrace hash. | |
1460 | */ | |
1461 | return (ftrace_hash_empty(hash->filter_hash) || | |
2b2c279c | 1462 | __ftrace_lookup_ip(hash->filter_hash, ip)) && |
fef5aeee | 1463 | (ftrace_hash_empty(hash->notrace_hash) || |
2b2c279c | 1464 | !__ftrace_lookup_ip(hash->notrace_hash, ip)); |
fef5aeee SRRH |
1465 | } |
1466 | ||
b848914c SR |
1467 | /* |
1468 | * Test the hashes for this ops to see if we want to call | |
1469 | * the ops->func or not. | |
1470 | * | |
1471 | * It's a match if the ip is in the ops->filter_hash or | |
1472 | * the filter_hash does not exist or is empty, | |
1473 | * AND | |
1474 | * the ip is not in the ops->notrace_hash. | |
cdbe61bf SR |
1475 | * |
1476 | * This needs to be called with preemption disabled as | |
74401729 | 1477 | * the hashes are freed with call_rcu(). |
b848914c | 1478 | */ |
3306fc4a | 1479 | int |
195a8afc | 1480 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs) |
b848914c | 1481 | { |
fef5aeee | 1482 | struct ftrace_ops_hash hash; |
b848914c SR |
1483 | int ret; |
1484 | ||
195a8afc SRRH |
1485 | #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
1486 | /* | |
1487 | * There's a small race when adding ops that the ftrace handler | |
1488 | * that wants regs, may be called without them. We can not | |
1489 | * allow that handler to be called if regs is NULL. | |
1490 | */ | |
1491 | if (regs == NULL && (ops->flags & FTRACE_OPS_FL_SAVE_REGS)) | |
1492 | return 0; | |
1493 | #endif | |
1494 | ||
f86f4180 CZ |
1495 | rcu_assign_pointer(hash.filter_hash, ops->func_hash->filter_hash); |
1496 | rcu_assign_pointer(hash.notrace_hash, ops->func_hash->notrace_hash); | |
b848914c | 1497 | |
fef5aeee | 1498 | if (hash_contains_ip(ip, &hash)) |
b848914c SR |
1499 | ret = 1; |
1500 | else | |
1501 | ret = 0; | |
b848914c SR |
1502 | |
1503 | return ret; | |
1504 | } | |
1505 | ||
493762fc SR |
1506 | /* |
1507 | * This is a double for. Do not use 'break' to break out of the loop, | |
1508 | * you must use a goto. | |
1509 | */ | |
1510 | #define do_for_each_ftrace_rec(pg, rec) \ | |
1511 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
1512 | int _____i; \ | |
1513 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
1514 | rec = &pg->records[_____i]; | |
1515 | ||
1516 | #define while_for_each_ftrace_rec() \ | |
1517 | } \ | |
1518 | } | |
1519 | ||
5855fead SR |
1520 | |
1521 | static int ftrace_cmp_recs(const void *a, const void *b) | |
1522 | { | |
a650e02a SR |
1523 | const struct dyn_ftrace *key = a; |
1524 | const struct dyn_ftrace *rec = b; | |
5855fead | 1525 | |
a650e02a | 1526 | if (key->flags < rec->ip) |
5855fead | 1527 | return -1; |
a650e02a SR |
1528 | if (key->ip >= rec->ip + MCOUNT_INSN_SIZE) |
1529 | return 1; | |
5855fead SR |
1530 | return 0; |
1531 | } | |
1532 | ||
7e16f581 SRV |
1533 | static struct dyn_ftrace *lookup_rec(unsigned long start, unsigned long end) |
1534 | { | |
1535 | struct ftrace_page *pg; | |
1536 | struct dyn_ftrace *rec = NULL; | |
1537 | struct dyn_ftrace key; | |
1538 | ||
1539 | key.ip = start; | |
1540 | key.flags = end; /* overload flags, as it is unsigned long */ | |
1541 | ||
1542 | for (pg = ftrace_pages_start; pg; pg = pg->next) { | |
1543 | if (end < pg->records[0].ip || | |
1544 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) | |
1545 | continue; | |
1546 | rec = bsearch(&key, pg->records, pg->index, | |
1547 | sizeof(struct dyn_ftrace), | |
1548 | ftrace_cmp_recs); | |
d9815bff AS |
1549 | if (rec) |
1550 | break; | |
7e16f581 SRV |
1551 | } |
1552 | return rec; | |
1553 | } | |
1554 | ||
04cf31a7 ME |
1555 | /** |
1556 | * ftrace_location_range - return the first address of a traced location | |
1557 | * if it touches the given ip range | |
1558 | * @start: start of range to search. | |
1559 | * @end: end of range to search (inclusive). @end points to the last byte | |
1560 | * to check. | |
1561 | * | |
1562 | * Returns rec->ip if the related ftrace location is a least partly within | |
1563 | * the given address range. That is, the first address of the instruction | |
1564 | * that is either a NOP or call to the function tracer. It checks the ftrace | |
1565 | * internal tables to determine if the address belongs or not. | |
1566 | */ | |
1567 | unsigned long ftrace_location_range(unsigned long start, unsigned long end) | |
c88fd863 | 1568 | { |
c88fd863 | 1569 | struct dyn_ftrace *rec; |
5855fead | 1570 | |
7e16f581 SRV |
1571 | rec = lookup_rec(start, end); |
1572 | if (rec) | |
1573 | return rec->ip; | |
c88fd863 SR |
1574 | |
1575 | return 0; | |
1576 | } | |
1577 | ||
a650e02a SR |
1578 | /** |
1579 | * ftrace_location - return true if the ip giving is a traced location | |
1580 | * @ip: the instruction pointer to check | |
1581 | * | |
f0cf973a | 1582 | * Returns rec->ip if @ip given is a pointer to a ftrace location. |
a650e02a SR |
1583 | * That is, the instruction that is either a NOP or call to |
1584 | * the function tracer. It checks the ftrace internal tables to | |
1585 | * determine if the address belongs or not. | |
1586 | */ | |
f0cf973a | 1587 | unsigned long ftrace_location(unsigned long ip) |
a650e02a SR |
1588 | { |
1589 | return ftrace_location_range(ip, ip); | |
1590 | } | |
1591 | ||
1592 | /** | |
1593 | * ftrace_text_reserved - return true if range contains an ftrace location | |
1594 | * @start: start of range to search | |
1595 | * @end: end of range to search (inclusive). @end points to the last byte to check. | |
1596 | * | |
1597 | * Returns 1 if @start and @end contains a ftrace location. | |
1598 | * That is, the instruction that is either a NOP or call to | |
1599 | * the function tracer. It checks the ftrace internal tables to | |
1600 | * determine if the address belongs or not. | |
1601 | */ | |
d88471cb | 1602 | int ftrace_text_reserved(const void *start, const void *end) |
a650e02a | 1603 | { |
f0cf973a SR |
1604 | unsigned long ret; |
1605 | ||
1606 | ret = ftrace_location_range((unsigned long)start, | |
1607 | (unsigned long)end); | |
1608 | ||
1609 | return (int)!!ret; | |
a650e02a SR |
1610 | } |
1611 | ||
4fbb48cb SRRH |
1612 | /* Test if ops registered to this rec needs regs */ |
1613 | static bool test_rec_ops_needs_regs(struct dyn_ftrace *rec) | |
1614 | { | |
1615 | struct ftrace_ops *ops; | |
1616 | bool keep_regs = false; | |
1617 | ||
1618 | for (ops = ftrace_ops_list; | |
1619 | ops != &ftrace_list_end; ops = ops->next) { | |
1620 | /* pass rec in as regs to have non-NULL val */ | |
1621 | if (ftrace_ops_test(ops, rec->ip, rec)) { | |
1622 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) { | |
1623 | keep_regs = true; | |
1624 | break; | |
1625 | } | |
1626 | } | |
1627 | } | |
1628 | ||
1629 | return keep_regs; | |
1630 | } | |
1631 | ||
a124692b CJ |
1632 | static struct ftrace_ops * |
1633 | ftrace_find_tramp_ops_any(struct dyn_ftrace *rec); | |
1634 | static struct ftrace_ops * | |
1635 | ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, struct ftrace_ops *ops); | |
1636 | ||
84b6d3e6 | 1637 | static bool __ftrace_hash_rec_update(struct ftrace_ops *ops, |
ed926f9b SR |
1638 | int filter_hash, |
1639 | bool inc) | |
1640 | { | |
1641 | struct ftrace_hash *hash; | |
1642 | struct ftrace_hash *other_hash; | |
1643 | struct ftrace_page *pg; | |
1644 | struct dyn_ftrace *rec; | |
84b6d3e6 | 1645 | bool update = false; |
ed926f9b | 1646 | int count = 0; |
8c08f0d5 | 1647 | int all = false; |
ed926f9b SR |
1648 | |
1649 | /* Only update if the ops has been registered */ | |
1650 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
84b6d3e6 | 1651 | return false; |
ed926f9b SR |
1652 | |
1653 | /* | |
1654 | * In the filter_hash case: | |
1655 | * If the count is zero, we update all records. | |
1656 | * Otherwise we just update the items in the hash. | |
1657 | * | |
1658 | * In the notrace_hash case: | |
1659 | * We enable the update in the hash. | |
1660 | * As disabling notrace means enabling the tracing, | |
1661 | * and enabling notrace means disabling, the inc variable | |
1662 | * gets inversed. | |
1663 | */ | |
1664 | if (filter_hash) { | |
33b7f99c SRRH |
1665 | hash = ops->func_hash->filter_hash; |
1666 | other_hash = ops->func_hash->notrace_hash; | |
06a51d93 | 1667 | if (ftrace_hash_empty(hash)) |
8c08f0d5 | 1668 | all = true; |
ed926f9b SR |
1669 | } else { |
1670 | inc = !inc; | |
33b7f99c SRRH |
1671 | hash = ops->func_hash->notrace_hash; |
1672 | other_hash = ops->func_hash->filter_hash; | |
ed926f9b SR |
1673 | /* |
1674 | * If the notrace hash has no items, | |
1675 | * then there's nothing to do. | |
1676 | */ | |
06a51d93 | 1677 | if (ftrace_hash_empty(hash)) |
84b6d3e6 | 1678 | return false; |
ed926f9b SR |
1679 | } |
1680 | ||
1681 | do_for_each_ftrace_rec(pg, rec) { | |
1682 | int in_other_hash = 0; | |
1683 | int in_hash = 0; | |
1684 | int match = 0; | |
1685 | ||
b7ffffbb SRRH |
1686 | if (rec->flags & FTRACE_FL_DISABLED) |
1687 | continue; | |
1688 | ||
ed926f9b SR |
1689 | if (all) { |
1690 | /* | |
1691 | * Only the filter_hash affects all records. | |
1692 | * Update if the record is not in the notrace hash. | |
1693 | */ | |
b848914c | 1694 | if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip)) |
ed926f9b SR |
1695 | match = 1; |
1696 | } else { | |
06a51d93 SR |
1697 | in_hash = !!ftrace_lookup_ip(hash, rec->ip); |
1698 | in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip); | |
ed926f9b SR |
1699 | |
1700 | /* | |
19eab4a4 SRRH |
1701 | * If filter_hash is set, we want to match all functions |
1702 | * that are in the hash but not in the other hash. | |
ed926f9b | 1703 | * |
19eab4a4 SRRH |
1704 | * If filter_hash is not set, then we are decrementing. |
1705 | * That means we match anything that is in the hash | |
1706 | * and also in the other_hash. That is, we need to turn | |
1707 | * off functions in the other hash because they are disabled | |
1708 | * by this hash. | |
ed926f9b SR |
1709 | */ |
1710 | if (filter_hash && in_hash && !in_other_hash) | |
1711 | match = 1; | |
1712 | else if (!filter_hash && in_hash && | |
06a51d93 | 1713 | (in_other_hash || ftrace_hash_empty(other_hash))) |
ed926f9b SR |
1714 | match = 1; |
1715 | } | |
1716 | if (!match) | |
1717 | continue; | |
1718 | ||
1719 | if (inc) { | |
1720 | rec->flags++; | |
0376bde1 | 1721 | if (FTRACE_WARN_ON(ftrace_rec_count(rec) == FTRACE_REF_MAX)) |
84b6d3e6 | 1722 | return false; |
79922b80 | 1723 | |
763e34e7 SRV |
1724 | if (ops->flags & FTRACE_OPS_FL_DIRECT) |
1725 | rec->flags |= FTRACE_FL_DIRECT; | |
1726 | ||
79922b80 SRRH |
1727 | /* |
1728 | * If there's only a single callback registered to a | |
1729 | * function, and the ops has a trampoline registered | |
1730 | * for it, then we can call it directly. | |
1731 | */ | |
fef5aeee | 1732 | if (ftrace_rec_count(rec) == 1 && ops->trampoline) |
79922b80 | 1733 | rec->flags |= FTRACE_FL_TRAMP; |
fef5aeee | 1734 | else |
79922b80 SRRH |
1735 | /* |
1736 | * If we are adding another function callback | |
1737 | * to this function, and the previous had a | |
bce0b6c5 SRRH |
1738 | * custom trampoline in use, then we need to go |
1739 | * back to the default trampoline. | |
79922b80 | 1740 | */ |
fef5aeee | 1741 | rec->flags &= ~FTRACE_FL_TRAMP; |
79922b80 | 1742 | |
08f6fba5 SR |
1743 | /* |
1744 | * If any ops wants regs saved for this function | |
1745 | * then all ops will get saved regs. | |
1746 | */ | |
1747 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) | |
1748 | rec->flags |= FTRACE_FL_REGS; | |
ed926f9b | 1749 | } else { |
0376bde1 | 1750 | if (FTRACE_WARN_ON(ftrace_rec_count(rec) == 0)) |
84b6d3e6 | 1751 | return false; |
ed926f9b | 1752 | rec->flags--; |
79922b80 | 1753 | |
763e34e7 SRV |
1754 | /* |
1755 | * Only the internal direct_ops should have the | |
1756 | * DIRECT flag set. Thus, if it is removing a | |
1757 | * function, then that function should no longer | |
1758 | * be direct. | |
1759 | */ | |
1760 | if (ops->flags & FTRACE_OPS_FL_DIRECT) | |
1761 | rec->flags &= ~FTRACE_FL_DIRECT; | |
1762 | ||
4fbb48cb SRRH |
1763 | /* |
1764 | * If the rec had REGS enabled and the ops that is | |
1765 | * being removed had REGS set, then see if there is | |
1766 | * still any ops for this record that wants regs. | |
1767 | * If not, we can stop recording them. | |
1768 | */ | |
0376bde1 | 1769 | if (ftrace_rec_count(rec) > 0 && |
4fbb48cb SRRH |
1770 | rec->flags & FTRACE_FL_REGS && |
1771 | ops->flags & FTRACE_OPS_FL_SAVE_REGS) { | |
1772 | if (!test_rec_ops_needs_regs(rec)) | |
1773 | rec->flags &= ~FTRACE_FL_REGS; | |
1774 | } | |
79922b80 | 1775 | |
fef5aeee | 1776 | /* |
a124692b CJ |
1777 | * The TRAMP needs to be set only if rec count |
1778 | * is decremented to one, and the ops that is | |
1779 | * left has a trampoline. As TRAMP can only be | |
1780 | * enabled if there is only a single ops attached | |
1781 | * to it. | |
fef5aeee | 1782 | */ |
a124692b CJ |
1783 | if (ftrace_rec_count(rec) == 1 && |
1784 | ftrace_find_tramp_ops_any(rec)) | |
1785 | rec->flags |= FTRACE_FL_TRAMP; | |
1786 | else | |
1787 | rec->flags &= ~FTRACE_FL_TRAMP; | |
fef5aeee | 1788 | |
79922b80 SRRH |
1789 | /* |
1790 | * flags will be cleared in ftrace_check_record() | |
1791 | * if rec count is zero. | |
1792 | */ | |
ed926f9b SR |
1793 | } |
1794 | count++; | |
84b6d3e6 JO |
1795 | |
1796 | /* Must match FTRACE_UPDATE_CALLS in ftrace_modify_all_code() */ | |
7375dca1 | 1797 | update |= ftrace_test_record(rec, true) != FTRACE_UPDATE_IGNORE; |
84b6d3e6 | 1798 | |
ed926f9b SR |
1799 | /* Shortcut, if we handled all records, we are done. */ |
1800 | if (!all && count == hash->count) | |
84b6d3e6 | 1801 | return update; |
ed926f9b | 1802 | } while_for_each_ftrace_rec(); |
84b6d3e6 JO |
1803 | |
1804 | return update; | |
ed926f9b SR |
1805 | } |
1806 | ||
84b6d3e6 | 1807 | static bool ftrace_hash_rec_disable(struct ftrace_ops *ops, |
ed926f9b SR |
1808 | int filter_hash) |
1809 | { | |
84b6d3e6 | 1810 | return __ftrace_hash_rec_update(ops, filter_hash, 0); |
ed926f9b SR |
1811 | } |
1812 | ||
84b6d3e6 | 1813 | static bool ftrace_hash_rec_enable(struct ftrace_ops *ops, |
ed926f9b SR |
1814 | int filter_hash) |
1815 | { | |
84b6d3e6 | 1816 | return __ftrace_hash_rec_update(ops, filter_hash, 1); |
ed926f9b SR |
1817 | } |
1818 | ||
84261912 SRRH |
1819 | static void ftrace_hash_rec_update_modify(struct ftrace_ops *ops, |
1820 | int filter_hash, int inc) | |
1821 | { | |
1822 | struct ftrace_ops *op; | |
1823 | ||
1824 | __ftrace_hash_rec_update(ops, filter_hash, inc); | |
1825 | ||
1826 | if (ops->func_hash != &global_ops.local_hash) | |
1827 | return; | |
1828 | ||
1829 | /* | |
1830 | * If the ops shares the global_ops hash, then we need to update | |
1831 | * all ops that are enabled and use this hash. | |
1832 | */ | |
1833 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
1834 | /* Already done */ | |
1835 | if (op == ops) | |
1836 | continue; | |
1837 | if (op->func_hash == &global_ops.local_hash) | |
1838 | __ftrace_hash_rec_update(op, filter_hash, inc); | |
1839 | } while_for_each_ftrace_op(op); | |
1840 | } | |
1841 | ||
1842 | static void ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, | |
1843 | int filter_hash) | |
1844 | { | |
1845 | ftrace_hash_rec_update_modify(ops, filter_hash, 0); | |
1846 | } | |
1847 | ||
1848 | static void ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, | |
1849 | int filter_hash) | |
1850 | { | |
1851 | ftrace_hash_rec_update_modify(ops, filter_hash, 1); | |
1852 | } | |
1853 | ||
f8b8be8a MH |
1854 | /* |
1855 | * Try to update IPMODIFY flag on each ftrace_rec. Return 0 if it is OK | |
1856 | * or no-needed to update, -EBUSY if it detects a conflict of the flag | |
1857 | * on a ftrace_rec, and -EINVAL if the new_hash tries to trace all recs. | |
1858 | * Note that old_hash and new_hash has below meanings | |
1859 | * - If the hash is NULL, it hits all recs (if IPMODIFY is set, this is rejected) | |
1860 | * - If the hash is EMPTY_HASH, it hits nothing | |
1861 | * - Anything else hits the recs which match the hash entries. | |
1862 | */ | |
1863 | static int __ftrace_hash_update_ipmodify(struct ftrace_ops *ops, | |
1864 | struct ftrace_hash *old_hash, | |
1865 | struct ftrace_hash *new_hash) | |
1866 | { | |
1867 | struct ftrace_page *pg; | |
1868 | struct dyn_ftrace *rec, *end = NULL; | |
1869 | int in_old, in_new; | |
1870 | ||
1871 | /* Only update if the ops has been registered */ | |
1872 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
1873 | return 0; | |
1874 | ||
1875 | if (!(ops->flags & FTRACE_OPS_FL_IPMODIFY)) | |
1876 | return 0; | |
1877 | ||
1878 | /* | |
1879 | * Since the IPMODIFY is a very address sensitive action, we do not | |
1880 | * allow ftrace_ops to set all functions to new hash. | |
1881 | */ | |
1882 | if (!new_hash || !old_hash) | |
1883 | return -EINVAL; | |
1884 | ||
1885 | /* Update rec->flags */ | |
1886 | do_for_each_ftrace_rec(pg, rec) { | |
546fece4 SRRH |
1887 | |
1888 | if (rec->flags & FTRACE_FL_DISABLED) | |
1889 | continue; | |
1890 | ||
f8b8be8a MH |
1891 | /* We need to update only differences of filter_hash */ |
1892 | in_old = !!ftrace_lookup_ip(old_hash, rec->ip); | |
1893 | in_new = !!ftrace_lookup_ip(new_hash, rec->ip); | |
1894 | if (in_old == in_new) | |
1895 | continue; | |
1896 | ||
1897 | if (in_new) { | |
1898 | /* New entries must ensure no others are using it */ | |
1899 | if (rec->flags & FTRACE_FL_IPMODIFY) | |
1900 | goto rollback; | |
1901 | rec->flags |= FTRACE_FL_IPMODIFY; | |
1902 | } else /* Removed entry */ | |
1903 | rec->flags &= ~FTRACE_FL_IPMODIFY; | |
1904 | } while_for_each_ftrace_rec(); | |
1905 | ||
1906 | return 0; | |
1907 | ||
1908 | rollback: | |
1909 | end = rec; | |
1910 | ||
1911 | /* Roll back what we did above */ | |
1912 | do_for_each_ftrace_rec(pg, rec) { | |
546fece4 SRRH |
1913 | |
1914 | if (rec->flags & FTRACE_FL_DISABLED) | |
1915 | continue; | |
1916 | ||
f8b8be8a MH |
1917 | if (rec == end) |
1918 | goto err_out; | |
1919 | ||
1920 | in_old = !!ftrace_lookup_ip(old_hash, rec->ip); | |
1921 | in_new = !!ftrace_lookup_ip(new_hash, rec->ip); | |
1922 | if (in_old == in_new) | |
1923 | continue; | |
1924 | ||
1925 | if (in_new) | |
1926 | rec->flags &= ~FTRACE_FL_IPMODIFY; | |
1927 | else | |
1928 | rec->flags |= FTRACE_FL_IPMODIFY; | |
1929 | } while_for_each_ftrace_rec(); | |
1930 | ||
1931 | err_out: | |
1932 | return -EBUSY; | |
1933 | } | |
1934 | ||
1935 | static int ftrace_hash_ipmodify_enable(struct ftrace_ops *ops) | |
1936 | { | |
1937 | struct ftrace_hash *hash = ops->func_hash->filter_hash; | |
1938 | ||
1939 | if (ftrace_hash_empty(hash)) | |
1940 | hash = NULL; | |
1941 | ||
1942 | return __ftrace_hash_update_ipmodify(ops, EMPTY_HASH, hash); | |
1943 | } | |
1944 | ||
1945 | /* Disabling always succeeds */ | |
1946 | static void ftrace_hash_ipmodify_disable(struct ftrace_ops *ops) | |
1947 | { | |
1948 | struct ftrace_hash *hash = ops->func_hash->filter_hash; | |
1949 | ||
1950 | if (ftrace_hash_empty(hash)) | |
1951 | hash = NULL; | |
1952 | ||
1953 | __ftrace_hash_update_ipmodify(ops, hash, EMPTY_HASH); | |
1954 | } | |
1955 | ||
1956 | static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops, | |
1957 | struct ftrace_hash *new_hash) | |
1958 | { | |
1959 | struct ftrace_hash *old_hash = ops->func_hash->filter_hash; | |
1960 | ||
1961 | if (ftrace_hash_empty(old_hash)) | |
1962 | old_hash = NULL; | |
1963 | ||
1964 | if (ftrace_hash_empty(new_hash)) | |
1965 | new_hash = NULL; | |
1966 | ||
1967 | return __ftrace_hash_update_ipmodify(ops, old_hash, new_hash); | |
1968 | } | |
1969 | ||
b05086c7 | 1970 | static void print_ip_ins(const char *fmt, const unsigned char *p) |
b17e8a37 SR |
1971 | { |
1972 | int i; | |
1973 | ||
1974 | printk(KERN_CONT "%s", fmt); | |
1975 | ||
1976 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
1977 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
1978 | } | |
1979 | ||
02a392a0 | 1980 | enum ftrace_bug_type ftrace_bug_type; |
b05086c7 | 1981 | const void *ftrace_expected; |
02a392a0 SRRH |
1982 | |
1983 | static void print_bug_type(void) | |
1984 | { | |
1985 | switch (ftrace_bug_type) { | |
1986 | case FTRACE_BUG_UNKNOWN: | |
1987 | break; | |
1988 | case FTRACE_BUG_INIT: | |
1989 | pr_info("Initializing ftrace call sites\n"); | |
1990 | break; | |
1991 | case FTRACE_BUG_NOP: | |
1992 | pr_info("Setting ftrace call site to NOP\n"); | |
1993 | break; | |
1994 | case FTRACE_BUG_CALL: | |
1995 | pr_info("Setting ftrace call site to call ftrace function\n"); | |
1996 | break; | |
1997 | case FTRACE_BUG_UPDATE: | |
1998 | pr_info("Updating ftrace call site to call a different ftrace function\n"); | |
1999 | break; | |
2000 | } | |
2001 | } | |
2002 | ||
c88fd863 SR |
2003 | /** |
2004 | * ftrace_bug - report and shutdown function tracer | |
2005 | * @failed: The failed type (EFAULT, EINVAL, EPERM) | |
4fd3279b | 2006 | * @rec: The record that failed |
c88fd863 SR |
2007 | * |
2008 | * The arch code that enables or disables the function tracing | |
2009 | * can call ftrace_bug() when it has detected a problem in | |
2010 | * modifying the code. @failed should be one of either: | |
2011 | * EFAULT - if the problem happens on reading the @ip address | |
2012 | * EINVAL - if what is read at @ip is not what was expected | |
9efb85c5 | 2013 | * EPERM - if the problem happens on writing to the @ip address |
c88fd863 | 2014 | */ |
4fd3279b | 2015 | void ftrace_bug(int failed, struct dyn_ftrace *rec) |
b17e8a37 | 2016 | { |
4fd3279b SRRH |
2017 | unsigned long ip = rec ? rec->ip : 0; |
2018 | ||
b17e8a37 SR |
2019 | switch (failed) { |
2020 | case -EFAULT: | |
2021 | FTRACE_WARN_ON_ONCE(1); | |
2022 | pr_info("ftrace faulted on modifying "); | |
2023 | print_ip_sym(ip); | |
2024 | break; | |
2025 | case -EINVAL: | |
2026 | FTRACE_WARN_ON_ONCE(1); | |
2027 | pr_info("ftrace failed to modify "); | |
2028 | print_ip_sym(ip); | |
b05086c7 | 2029 | print_ip_ins(" actual: ", (unsigned char *)ip); |
4fd3279b | 2030 | pr_cont("\n"); |
b05086c7 SRRH |
2031 | if (ftrace_expected) { |
2032 | print_ip_ins(" expected: ", ftrace_expected); | |
2033 | pr_cont("\n"); | |
2034 | } | |
b17e8a37 SR |
2035 | break; |
2036 | case -EPERM: | |
2037 | FTRACE_WARN_ON_ONCE(1); | |
2038 | pr_info("ftrace faulted on writing "); | |
2039 | print_ip_sym(ip); | |
2040 | break; | |
2041 | default: | |
2042 | FTRACE_WARN_ON_ONCE(1); | |
2043 | pr_info("ftrace faulted on unknown error "); | |
2044 | print_ip_sym(ip); | |
2045 | } | |
02a392a0 | 2046 | print_bug_type(); |
4fd3279b SRRH |
2047 | if (rec) { |
2048 | struct ftrace_ops *ops = NULL; | |
2049 | ||
2050 | pr_info("ftrace record flags: %lx\n", rec->flags); | |
2051 | pr_cont(" (%ld)%s", ftrace_rec_count(rec), | |
2052 | rec->flags & FTRACE_FL_REGS ? " R" : " "); | |
2053 | if (rec->flags & FTRACE_FL_TRAMP_EN) { | |
2054 | ops = ftrace_find_tramp_ops_any(rec); | |
39daa7b9 SRRH |
2055 | if (ops) { |
2056 | do { | |
2057 | pr_cont("\ttramp: %pS (%pS)", | |
2058 | (void *)ops->trampoline, | |
2059 | (void *)ops->func); | |
2060 | ops = ftrace_find_tramp_ops_next(rec, ops); | |
2061 | } while (ops); | |
2062 | } else | |
4fd3279b SRRH |
2063 | pr_cont("\ttramp: ERROR!"); |
2064 | ||
2065 | } | |
2066 | ip = ftrace_get_addr_curr(rec); | |
39daa7b9 | 2067 | pr_cont("\n expected tramp: %lx\n", ip); |
4fd3279b | 2068 | } |
b17e8a37 SR |
2069 | } |
2070 | ||
7375dca1 | 2071 | static int ftrace_check_record(struct dyn_ftrace *rec, bool enable, bool update) |
5072c59f | 2072 | { |
64fbcd16 | 2073 | unsigned long flag = 0UL; |
e7d3737e | 2074 | |
02a392a0 SRRH |
2075 | ftrace_bug_type = FTRACE_BUG_UNKNOWN; |
2076 | ||
b7ffffbb SRRH |
2077 | if (rec->flags & FTRACE_FL_DISABLED) |
2078 | return FTRACE_UPDATE_IGNORE; | |
2079 | ||
982c350b | 2080 | /* |
30fb6aa7 | 2081 | * If we are updating calls: |
982c350b | 2082 | * |
ed926f9b SR |
2083 | * If the record has a ref count, then we need to enable it |
2084 | * because someone is using it. | |
982c350b | 2085 | * |
ed926f9b SR |
2086 | * Otherwise we make sure its disabled. |
2087 | * | |
30fb6aa7 | 2088 | * If we are disabling calls, then disable all records that |
ed926f9b | 2089 | * are enabled. |
982c350b | 2090 | */ |
0376bde1 | 2091 | if (enable && ftrace_rec_count(rec)) |
ed926f9b | 2092 | flag = FTRACE_FL_ENABLED; |
982c350b | 2093 | |
08f6fba5 | 2094 | /* |
79922b80 SRRH |
2095 | * If enabling and the REGS flag does not match the REGS_EN, or |
2096 | * the TRAMP flag doesn't match the TRAMP_EN, then do not ignore | |
2097 | * this record. Set flags to fail the compare against ENABLED. | |
763e34e7 | 2098 | * Same for direct calls. |
08f6fba5 | 2099 | */ |
79922b80 | 2100 | if (flag) { |
763e34e7 | 2101 | if (!(rec->flags & FTRACE_FL_REGS) != |
79922b80 SRRH |
2102 | !(rec->flags & FTRACE_FL_REGS_EN)) |
2103 | flag |= FTRACE_FL_REGS; | |
2104 | ||
763e34e7 | 2105 | if (!(rec->flags & FTRACE_FL_TRAMP) != |
79922b80 SRRH |
2106 | !(rec->flags & FTRACE_FL_TRAMP_EN)) |
2107 | flag |= FTRACE_FL_TRAMP; | |
763e34e7 SRV |
2108 | |
2109 | /* | |
2110 | * Direct calls are special, as count matters. | |
2111 | * We must test the record for direct, if the | |
2112 | * DIRECT and DIRECT_EN do not match, but only | |
2113 | * if the count is 1. That's because, if the | |
2114 | * count is something other than one, we do not | |
2115 | * want the direct enabled (it will be done via the | |
2116 | * direct helper). But if DIRECT_EN is set, and | |
2117 | * the count is not one, we need to clear it. | |
2118 | */ | |
2119 | if (ftrace_rec_count(rec) == 1) { | |
2120 | if (!(rec->flags & FTRACE_FL_DIRECT) != | |
2121 | !(rec->flags & FTRACE_FL_DIRECT_EN)) | |
2122 | flag |= FTRACE_FL_DIRECT; | |
2123 | } else if (rec->flags & FTRACE_FL_DIRECT_EN) { | |
2124 | flag |= FTRACE_FL_DIRECT; | |
2125 | } | |
79922b80 | 2126 | } |
08f6fba5 | 2127 | |
64fbcd16 XG |
2128 | /* If the state of this record hasn't changed, then do nothing */ |
2129 | if ((rec->flags & FTRACE_FL_ENABLED) == flag) | |
c88fd863 | 2130 | return FTRACE_UPDATE_IGNORE; |
982c350b | 2131 | |
64fbcd16 | 2132 | if (flag) { |
08f6fba5 SR |
2133 | /* Save off if rec is being enabled (for return value) */ |
2134 | flag ^= rec->flags & FTRACE_FL_ENABLED; | |
2135 | ||
2136 | if (update) { | |
c88fd863 | 2137 | rec->flags |= FTRACE_FL_ENABLED; |
08f6fba5 SR |
2138 | if (flag & FTRACE_FL_REGS) { |
2139 | if (rec->flags & FTRACE_FL_REGS) | |
2140 | rec->flags |= FTRACE_FL_REGS_EN; | |
2141 | else | |
2142 | rec->flags &= ~FTRACE_FL_REGS_EN; | |
2143 | } | |
79922b80 SRRH |
2144 | if (flag & FTRACE_FL_TRAMP) { |
2145 | if (rec->flags & FTRACE_FL_TRAMP) | |
2146 | rec->flags |= FTRACE_FL_TRAMP_EN; | |
2147 | else | |
2148 | rec->flags &= ~FTRACE_FL_TRAMP_EN; | |
2149 | } | |
763e34e7 SRV |
2150 | if (flag & FTRACE_FL_DIRECT) { |
2151 | /* | |
2152 | * If there's only one user (direct_ops helper) | |
2153 | * then we can call the direct function | |
2154 | * directly (no ftrace trampoline). | |
2155 | */ | |
2156 | if (ftrace_rec_count(rec) == 1) { | |
2157 | if (rec->flags & FTRACE_FL_DIRECT) | |
2158 | rec->flags |= FTRACE_FL_DIRECT_EN; | |
2159 | else | |
2160 | rec->flags &= ~FTRACE_FL_DIRECT_EN; | |
2161 | } else { | |
2162 | /* | |
2163 | * Can only call directly if there's | |
2164 | * only one callback to the function. | |
2165 | */ | |
2166 | rec->flags &= ~FTRACE_FL_DIRECT_EN; | |
2167 | } | |
2168 | } | |
08f6fba5 SR |
2169 | } |
2170 | ||
2171 | /* | |
2172 | * If this record is being updated from a nop, then | |
2173 | * return UPDATE_MAKE_CALL. | |
08f6fba5 SR |
2174 | * Otherwise, |
2175 | * return UPDATE_MODIFY_CALL to tell the caller to convert | |
f1b2f2bd | 2176 | * from the save regs, to a non-save regs function or |
79922b80 | 2177 | * vice versa, or from a trampoline call. |
08f6fba5 | 2178 | */ |
02a392a0 SRRH |
2179 | if (flag & FTRACE_FL_ENABLED) { |
2180 | ftrace_bug_type = FTRACE_BUG_CALL; | |
08f6fba5 | 2181 | return FTRACE_UPDATE_MAKE_CALL; |
02a392a0 | 2182 | } |
f1b2f2bd | 2183 | |
02a392a0 | 2184 | ftrace_bug_type = FTRACE_BUG_UPDATE; |
f1b2f2bd | 2185 | return FTRACE_UPDATE_MODIFY_CALL; |
c88fd863 SR |
2186 | } |
2187 | ||
08f6fba5 SR |
2188 | if (update) { |
2189 | /* If there's no more users, clear all flags */ | |
0376bde1 | 2190 | if (!ftrace_rec_count(rec)) |
08f6fba5 SR |
2191 | rec->flags = 0; |
2192 | else | |
b24d443b SRRH |
2193 | /* |
2194 | * Just disable the record, but keep the ops TRAMP | |
2195 | * and REGS states. The _EN flags must be disabled though. | |
2196 | */ | |
2197 | rec->flags &= ~(FTRACE_FL_ENABLED | FTRACE_FL_TRAMP_EN | | |
763e34e7 | 2198 | FTRACE_FL_REGS_EN | FTRACE_FL_DIRECT_EN); |
08f6fba5 | 2199 | } |
c88fd863 | 2200 | |
02a392a0 | 2201 | ftrace_bug_type = FTRACE_BUG_NOP; |
c88fd863 SR |
2202 | return FTRACE_UPDATE_MAKE_NOP; |
2203 | } | |
2204 | ||
2205 | /** | |
2206 | * ftrace_update_record, set a record that now is tracing or not | |
2207 | * @rec: the record to update | |
7375dca1 | 2208 | * @enable: set to true if the record is tracing, false to force disable |
c88fd863 SR |
2209 | * |
2210 | * The records that represent all functions that can be traced need | |
2211 | * to be updated when tracing has been enabled. | |
2212 | */ | |
7375dca1 | 2213 | int ftrace_update_record(struct dyn_ftrace *rec, bool enable) |
c88fd863 | 2214 | { |
7375dca1 | 2215 | return ftrace_check_record(rec, enable, true); |
c88fd863 SR |
2216 | } |
2217 | ||
2218 | /** | |
2219 | * ftrace_test_record, check if the record has been enabled or not | |
2220 | * @rec: the record to test | |
7375dca1 | 2221 | * @enable: set to true to check if enabled, false if it is disabled |
c88fd863 SR |
2222 | * |
2223 | * The arch code may need to test if a record is already set to | |
2224 | * tracing to determine how to modify the function code that it | |
2225 | * represents. | |
2226 | */ | |
7375dca1 | 2227 | int ftrace_test_record(struct dyn_ftrace *rec, bool enable) |
c88fd863 | 2228 | { |
7375dca1 | 2229 | return ftrace_check_record(rec, enable, false); |
c88fd863 SR |
2230 | } |
2231 | ||
5fecaa04 SRRH |
2232 | static struct ftrace_ops * |
2233 | ftrace_find_tramp_ops_any(struct dyn_ftrace *rec) | |
2234 | { | |
2235 | struct ftrace_ops *op; | |
fef5aeee | 2236 | unsigned long ip = rec->ip; |
5fecaa04 SRRH |
2237 | |
2238 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
2239 | ||
2240 | if (!op->trampoline) | |
2241 | continue; | |
2242 | ||
fef5aeee | 2243 | if (hash_contains_ip(ip, op->func_hash)) |
5fecaa04 SRRH |
2244 | return op; |
2245 | } while_for_each_ftrace_op(op); | |
2246 | ||
2247 | return NULL; | |
2248 | } | |
2249 | ||
39daa7b9 SRRH |
2250 | static struct ftrace_ops * |
2251 | ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, | |
2252 | struct ftrace_ops *op) | |
2253 | { | |
2254 | unsigned long ip = rec->ip; | |
2255 | ||
2256 | while_for_each_ftrace_op(op) { | |
2257 | ||
2258 | if (!op->trampoline) | |
2259 | continue; | |
2260 | ||
2261 | if (hash_contains_ip(ip, op->func_hash)) | |
2262 | return op; | |
2263 | } | |
2264 | ||
2265 | return NULL; | |
2266 | } | |
2267 | ||
79922b80 SRRH |
2268 | static struct ftrace_ops * |
2269 | ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec) | |
2270 | { | |
2271 | struct ftrace_ops *op; | |
fef5aeee | 2272 | unsigned long ip = rec->ip; |
79922b80 | 2273 | |
fef5aeee SRRH |
2274 | /* |
2275 | * Need to check removed ops first. | |
2276 | * If they are being removed, and this rec has a tramp, | |
2277 | * and this rec is in the ops list, then it would be the | |
2278 | * one with the tramp. | |
2279 | */ | |
2280 | if (removed_ops) { | |
2281 | if (hash_contains_ip(ip, &removed_ops->old_hash)) | |
79922b80 SRRH |
2282 | return removed_ops; |
2283 | } | |
2284 | ||
fef5aeee SRRH |
2285 | /* |
2286 | * Need to find the current trampoline for a rec. | |
2287 | * Now, a trampoline is only attached to a rec if there | |
2288 | * was a single 'ops' attached to it. But this can be called | |
2289 | * when we are adding another op to the rec or removing the | |
2290 | * current one. Thus, if the op is being added, we can | |
2291 | * ignore it because it hasn't attached itself to the rec | |
4fc40904 SRRH |
2292 | * yet. |
2293 | * | |
2294 | * If an ops is being modified (hooking to different functions) | |
2295 | * then we don't care about the new functions that are being | |
2296 | * added, just the old ones (that are probably being removed). | |
2297 | * | |
2298 | * If we are adding an ops to a function that already is using | |
2299 | * a trampoline, it needs to be removed (trampolines are only | |
2300 | * for single ops connected), then an ops that is not being | |
2301 | * modified also needs to be checked. | |
fef5aeee | 2302 | */ |
79922b80 | 2303 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
fef5aeee SRRH |
2304 | |
2305 | if (!op->trampoline) | |
2306 | continue; | |
2307 | ||
2308 | /* | |
2309 | * If the ops is being added, it hasn't gotten to | |
2310 | * the point to be removed from this tree yet. | |
2311 | */ | |
2312 | if (op->flags & FTRACE_OPS_FL_ADDING) | |
79922b80 SRRH |
2313 | continue; |
2314 | ||
4fc40904 | 2315 | |
fef5aeee | 2316 | /* |
4fc40904 SRRH |
2317 | * If the ops is being modified and is in the old |
2318 | * hash, then it is probably being removed from this | |
2319 | * function. | |
fef5aeee | 2320 | */ |
fef5aeee SRRH |
2321 | if ((op->flags & FTRACE_OPS_FL_MODIFYING) && |
2322 | hash_contains_ip(ip, &op->old_hash)) | |
79922b80 | 2323 | return op; |
4fc40904 SRRH |
2324 | /* |
2325 | * If the ops is not being added or modified, and it's | |
2326 | * in its normal filter hash, then this must be the one | |
2327 | * we want! | |
2328 | */ | |
2329 | if (!(op->flags & FTRACE_OPS_FL_MODIFYING) && | |
2330 | hash_contains_ip(ip, op->func_hash)) | |
2331 | return op; | |
79922b80 SRRH |
2332 | |
2333 | } while_for_each_ftrace_op(op); | |
2334 | ||
2335 | return NULL; | |
2336 | } | |
2337 | ||
2338 | static struct ftrace_ops * | |
2339 | ftrace_find_tramp_ops_new(struct dyn_ftrace *rec) | |
2340 | { | |
2341 | struct ftrace_ops *op; | |
fef5aeee | 2342 | unsigned long ip = rec->ip; |
79922b80 SRRH |
2343 | |
2344 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
2345 | /* pass rec in as regs to have non-NULL val */ | |
fef5aeee | 2346 | if (hash_contains_ip(ip, op->func_hash)) |
79922b80 SRRH |
2347 | return op; |
2348 | } while_for_each_ftrace_op(op); | |
2349 | ||
2350 | return NULL; | |
2351 | } | |
2352 | ||
763e34e7 SRV |
2353 | #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS |
2354 | /* Protected by rcu_tasks for reading, and direct_mutex for writing */ | |
2355 | static struct ftrace_hash *direct_functions = EMPTY_HASH; | |
2356 | static DEFINE_MUTEX(direct_mutex); | |
a3ad1a7e | 2357 | int ftrace_direct_func_count; |
763e34e7 SRV |
2358 | |
2359 | /* | |
2360 | * Search the direct_functions hash to see if the given instruction pointer | |
2361 | * has a direct caller attached to it. | |
2362 | */ | |
ff205766 | 2363 | unsigned long ftrace_find_rec_direct(unsigned long ip) |
763e34e7 SRV |
2364 | { |
2365 | struct ftrace_func_entry *entry; | |
2366 | ||
2367 | entry = __ftrace_lookup_ip(direct_functions, ip); | |
2368 | if (!entry) | |
2369 | return 0; | |
2370 | ||
2371 | return entry->direct; | |
2372 | } | |
2373 | ||
2374 | static void call_direct_funcs(unsigned long ip, unsigned long pip, | |
2375 | struct ftrace_ops *ops, struct pt_regs *regs) | |
2376 | { | |
2377 | unsigned long addr; | |
2378 | ||
ff205766 | 2379 | addr = ftrace_find_rec_direct(ip); |
763e34e7 SRV |
2380 | if (!addr) |
2381 | return; | |
2382 | ||
2383 | arch_ftrace_set_direct_caller(regs, addr); | |
2384 | } | |
2385 | ||
2386 | struct ftrace_ops direct_ops = { | |
2387 | .func = call_direct_funcs, | |
2388 | .flags = FTRACE_OPS_FL_IPMODIFY | FTRACE_OPS_FL_RECURSION_SAFE | |
2389 | | FTRACE_OPS_FL_DIRECT | FTRACE_OPS_FL_SAVE_REGS | |
2390 | | FTRACE_OPS_FL_PERMANENT, | |
2391 | }; | |
763e34e7 SRV |
2392 | #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */ |
2393 | ||
7413af1f SRRH |
2394 | /** |
2395 | * ftrace_get_addr_new - Get the call address to set to | |
2396 | * @rec: The ftrace record descriptor | |
2397 | * | |
2398 | * If the record has the FTRACE_FL_REGS set, that means that it | |
2399 | * wants to convert to a callback that saves all regs. If FTRACE_FL_REGS | |
2400 | * is not not set, then it wants to convert to the normal callback. | |
2401 | * | |
2402 | * Returns the address of the trampoline to set to | |
2403 | */ | |
2404 | unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec) | |
2405 | { | |
79922b80 | 2406 | struct ftrace_ops *ops; |
763e34e7 SRV |
2407 | unsigned long addr; |
2408 | ||
2409 | if ((rec->flags & FTRACE_FL_DIRECT) && | |
2410 | (ftrace_rec_count(rec) == 1)) { | |
ff205766 | 2411 | addr = ftrace_find_rec_direct(rec->ip); |
763e34e7 SRV |
2412 | if (addr) |
2413 | return addr; | |
2414 | WARN_ON_ONCE(1); | |
2415 | } | |
79922b80 SRRH |
2416 | |
2417 | /* Trampolines take precedence over regs */ | |
2418 | if (rec->flags & FTRACE_FL_TRAMP) { | |
2419 | ops = ftrace_find_tramp_ops_new(rec); | |
2420 | if (FTRACE_WARN_ON(!ops || !ops->trampoline)) { | |
bce0b6c5 SRRH |
2421 | pr_warn("Bad trampoline accounting at: %p (%pS) (%lx)\n", |
2422 | (void *)rec->ip, (void *)rec->ip, rec->flags); | |
79922b80 SRRH |
2423 | /* Ftrace is shutting down, return anything */ |
2424 | return (unsigned long)FTRACE_ADDR; | |
2425 | } | |
2426 | return ops->trampoline; | |
2427 | } | |
2428 | ||
7413af1f SRRH |
2429 | if (rec->flags & FTRACE_FL_REGS) |
2430 | return (unsigned long)FTRACE_REGS_ADDR; | |
2431 | else | |
2432 | return (unsigned long)FTRACE_ADDR; | |
2433 | } | |
2434 | ||
2435 | /** | |
2436 | * ftrace_get_addr_curr - Get the call address that is already there | |
2437 | * @rec: The ftrace record descriptor | |
2438 | * | |
2439 | * The FTRACE_FL_REGS_EN is set when the record already points to | |
2440 | * a function that saves all the regs. Basically the '_EN' version | |
2441 | * represents the current state of the function. | |
2442 | * | |
2443 | * Returns the address of the trampoline that is currently being called | |
2444 | */ | |
2445 | unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec) | |
2446 | { | |
79922b80 | 2447 | struct ftrace_ops *ops; |
763e34e7 SRV |
2448 | unsigned long addr; |
2449 | ||
2450 | /* Direct calls take precedence over trampolines */ | |
2451 | if (rec->flags & FTRACE_FL_DIRECT_EN) { | |
ff205766 | 2452 | addr = ftrace_find_rec_direct(rec->ip); |
763e34e7 SRV |
2453 | if (addr) |
2454 | return addr; | |
2455 | WARN_ON_ONCE(1); | |
2456 | } | |
79922b80 SRRH |
2457 | |
2458 | /* Trampolines take precedence over regs */ | |
2459 | if (rec->flags & FTRACE_FL_TRAMP_EN) { | |
2460 | ops = ftrace_find_tramp_ops_curr(rec); | |
2461 | if (FTRACE_WARN_ON(!ops)) { | |
a395d6a7 JP |
2462 | pr_warn("Bad trampoline accounting at: %p (%pS)\n", |
2463 | (void *)rec->ip, (void *)rec->ip); | |
79922b80 SRRH |
2464 | /* Ftrace is shutting down, return anything */ |
2465 | return (unsigned long)FTRACE_ADDR; | |
2466 | } | |
2467 | return ops->trampoline; | |
2468 | } | |
2469 | ||
7413af1f SRRH |
2470 | if (rec->flags & FTRACE_FL_REGS_EN) |
2471 | return (unsigned long)FTRACE_REGS_ADDR; | |
2472 | else | |
2473 | return (unsigned long)FTRACE_ADDR; | |
2474 | } | |
2475 | ||
c88fd863 | 2476 | static int |
7375dca1 | 2477 | __ftrace_replace_code(struct dyn_ftrace *rec, bool enable) |
c88fd863 | 2478 | { |
08f6fba5 | 2479 | unsigned long ftrace_old_addr; |
c88fd863 SR |
2480 | unsigned long ftrace_addr; |
2481 | int ret; | |
2482 | ||
7c0868e0 | 2483 | ftrace_addr = ftrace_get_addr_new(rec); |
c88fd863 | 2484 | |
7c0868e0 SRRH |
2485 | /* This needs to be done before we call ftrace_update_record */ |
2486 | ftrace_old_addr = ftrace_get_addr_curr(rec); | |
2487 | ||
2488 | ret = ftrace_update_record(rec, enable); | |
08f6fba5 | 2489 | |
02a392a0 SRRH |
2490 | ftrace_bug_type = FTRACE_BUG_UNKNOWN; |
2491 | ||
c88fd863 SR |
2492 | switch (ret) { |
2493 | case FTRACE_UPDATE_IGNORE: | |
2494 | return 0; | |
2495 | ||
2496 | case FTRACE_UPDATE_MAKE_CALL: | |
02a392a0 | 2497 | ftrace_bug_type = FTRACE_BUG_CALL; |
64fbcd16 | 2498 | return ftrace_make_call(rec, ftrace_addr); |
c88fd863 SR |
2499 | |
2500 | case FTRACE_UPDATE_MAKE_NOP: | |
02a392a0 | 2501 | ftrace_bug_type = FTRACE_BUG_NOP; |
39b5552c | 2502 | return ftrace_make_nop(NULL, rec, ftrace_old_addr); |
08f6fba5 | 2503 | |
08f6fba5 | 2504 | case FTRACE_UPDATE_MODIFY_CALL: |
02a392a0 | 2505 | ftrace_bug_type = FTRACE_BUG_UPDATE; |
08f6fba5 | 2506 | return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr); |
5072c59f SR |
2507 | } |
2508 | ||
9efb85c5 | 2509 | return -1; /* unknown ftrace bug */ |
5072c59f SR |
2510 | } |
2511 | ||
a0572f68 | 2512 | void __weak ftrace_replace_code(int mod_flags) |
3c1720f0 | 2513 | { |
3c1720f0 SR |
2514 | struct dyn_ftrace *rec; |
2515 | struct ftrace_page *pg; | |
7375dca1 | 2516 | bool enable = mod_flags & FTRACE_MODIFY_ENABLE_FL; |
a0572f68 | 2517 | int schedulable = mod_flags & FTRACE_MODIFY_MAY_SLEEP_FL; |
6a24a244 | 2518 | int failed; |
3c1720f0 | 2519 | |
45a4a237 SR |
2520 | if (unlikely(ftrace_disabled)) |
2521 | return; | |
2522 | ||
265c831c | 2523 | do_for_each_ftrace_rec(pg, rec) { |
546fece4 SRRH |
2524 | |
2525 | if (rec->flags & FTRACE_FL_DISABLED) | |
2526 | continue; | |
2527 | ||
e4f5d544 | 2528 | failed = __ftrace_replace_code(rec, enable); |
fa9d13cf | 2529 | if (failed) { |
4fd3279b | 2530 | ftrace_bug(failed, rec); |
3279ba37 SR |
2531 | /* Stop processing */ |
2532 | return; | |
3c1720f0 | 2533 | } |
a0572f68 SRV |
2534 | if (schedulable) |
2535 | cond_resched(); | |
265c831c | 2536 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
2537 | } |
2538 | ||
c88fd863 SR |
2539 | struct ftrace_rec_iter { |
2540 | struct ftrace_page *pg; | |
2541 | int index; | |
2542 | }; | |
2543 | ||
2544 | /** | |
2545 | * ftrace_rec_iter_start, start up iterating over traced functions | |
2546 | * | |
2547 | * Returns an iterator handle that is used to iterate over all | |
2548 | * the records that represent address locations where functions | |
2549 | * are traced. | |
2550 | * | |
2551 | * May return NULL if no records are available. | |
2552 | */ | |
2553 | struct ftrace_rec_iter *ftrace_rec_iter_start(void) | |
2554 | { | |
2555 | /* | |
2556 | * We only use a single iterator. | |
2557 | * Protected by the ftrace_lock mutex. | |
2558 | */ | |
2559 | static struct ftrace_rec_iter ftrace_rec_iter; | |
2560 | struct ftrace_rec_iter *iter = &ftrace_rec_iter; | |
2561 | ||
2562 | iter->pg = ftrace_pages_start; | |
2563 | iter->index = 0; | |
2564 | ||
2565 | /* Could have empty pages */ | |
2566 | while (iter->pg && !iter->pg->index) | |
2567 | iter->pg = iter->pg->next; | |
2568 | ||
2569 | if (!iter->pg) | |
2570 | return NULL; | |
2571 | ||
2572 | return iter; | |
2573 | } | |
2574 | ||
2575 | /** | |
2576 | * ftrace_rec_iter_next, get the next record to process. | |
2577 | * @iter: The handle to the iterator. | |
2578 | * | |
2579 | * Returns the next iterator after the given iterator @iter. | |
2580 | */ | |
2581 | struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter) | |
2582 | { | |
2583 | iter->index++; | |
2584 | ||
2585 | if (iter->index >= iter->pg->index) { | |
2586 | iter->pg = iter->pg->next; | |
2587 | iter->index = 0; | |
2588 | ||
2589 | /* Could have empty pages */ | |
2590 | while (iter->pg && !iter->pg->index) | |
2591 | iter->pg = iter->pg->next; | |
2592 | } | |
2593 | ||
2594 | if (!iter->pg) | |
2595 | return NULL; | |
2596 | ||
2597 | return iter; | |
2598 | } | |
2599 | ||
2600 | /** | |
2601 | * ftrace_rec_iter_record, get the record at the iterator location | |
2602 | * @iter: The current iterator location | |
2603 | * | |
2604 | * Returns the record that the current @iter is at. | |
2605 | */ | |
2606 | struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter) | |
2607 | { | |
2608 | return &iter->pg->records[iter->index]; | |
2609 | } | |
2610 | ||
492a7ea5 | 2611 | static int |
fbf6c73c | 2612 | ftrace_nop_initialize(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 | 2613 | { |
593eb8a2 | 2614 | int ret; |
3c1720f0 | 2615 | |
45a4a237 SR |
2616 | if (unlikely(ftrace_disabled)) |
2617 | return 0; | |
2618 | ||
fbf6c73c | 2619 | ret = ftrace_init_nop(mod, rec); |
593eb8a2 | 2620 | if (ret) { |
02a392a0 | 2621 | ftrace_bug_type = FTRACE_BUG_INIT; |
4fd3279b | 2622 | ftrace_bug(ret, rec); |
492a7ea5 | 2623 | return 0; |
37ad5084 | 2624 | } |
492a7ea5 | 2625 | return 1; |
3c1720f0 SR |
2626 | } |
2627 | ||
000ab691 SR |
2628 | /* |
2629 | * archs can override this function if they must do something | |
2630 | * before the modifying code is performed. | |
2631 | */ | |
2632 | int __weak ftrace_arch_code_modify_prepare(void) | |
2633 | { | |
2634 | return 0; | |
2635 | } | |
2636 | ||
2637 | /* | |
2638 | * archs can override this function if they must do something | |
2639 | * after the modifying code is performed. | |
2640 | */ | |
2641 | int __weak ftrace_arch_code_modify_post_process(void) | |
2642 | { | |
2643 | return 0; | |
2644 | } | |
2645 | ||
8ed3e2cf | 2646 | void ftrace_modify_all_code(int command) |
3d083395 | 2647 | { |
59338f75 | 2648 | int update = command & FTRACE_UPDATE_TRACE_FUNC; |
a0572f68 | 2649 | int mod_flags = 0; |
cd21067f | 2650 | int err = 0; |
59338f75 | 2651 | |
a0572f68 SRV |
2652 | if (command & FTRACE_MAY_SLEEP) |
2653 | mod_flags = FTRACE_MODIFY_MAY_SLEEP_FL; | |
2654 | ||
59338f75 SRRH |
2655 | /* |
2656 | * If the ftrace_caller calls a ftrace_ops func directly, | |
2657 | * we need to make sure that it only traces functions it | |
2658 | * expects to trace. When doing the switch of functions, | |
2659 | * we need to update to the ftrace_ops_list_func first | |
2660 | * before the transition between old and new calls are set, | |
2661 | * as the ftrace_ops_list_func will check the ops hashes | |
2662 | * to make sure the ops are having the right functions | |
2663 | * traced. | |
2664 | */ | |
cd21067f PM |
2665 | if (update) { |
2666 | err = ftrace_update_ftrace_func(ftrace_ops_list_func); | |
2667 | if (FTRACE_WARN_ON(err)) | |
2668 | return; | |
2669 | } | |
59338f75 | 2670 | |
8ed3e2cf | 2671 | if (command & FTRACE_UPDATE_CALLS) |
a0572f68 | 2672 | ftrace_replace_code(mod_flags | FTRACE_MODIFY_ENABLE_FL); |
8ed3e2cf | 2673 | else if (command & FTRACE_DISABLE_CALLS) |
a0572f68 | 2674 | ftrace_replace_code(mod_flags); |
d61f82d0 | 2675 | |
405e1d83 SRRH |
2676 | if (update && ftrace_trace_function != ftrace_ops_list_func) { |
2677 | function_trace_op = set_function_trace_op; | |
2678 | smp_wmb(); | |
2679 | /* If irqs are disabled, we are in stop machine */ | |
2680 | if (!irqs_disabled()) | |
2681 | smp_call_function(ftrace_sync_ipi, NULL, 1); | |
cd21067f PM |
2682 | err = ftrace_update_ftrace_func(ftrace_trace_function); |
2683 | if (FTRACE_WARN_ON(err)) | |
2684 | return; | |
405e1d83 | 2685 | } |
d61f82d0 | 2686 | |
8ed3e2cf | 2687 | if (command & FTRACE_START_FUNC_RET) |
cd21067f | 2688 | err = ftrace_enable_ftrace_graph_caller(); |
8ed3e2cf | 2689 | else if (command & FTRACE_STOP_FUNC_RET) |
cd21067f PM |
2690 | err = ftrace_disable_ftrace_graph_caller(); |
2691 | FTRACE_WARN_ON(err); | |
8ed3e2cf SR |
2692 | } |
2693 | ||
2694 | static int __ftrace_modify_code(void *data) | |
2695 | { | |
2696 | int *command = data; | |
2697 | ||
2698 | ftrace_modify_all_code(*command); | |
5a45cfe1 | 2699 | |
d61f82d0 | 2700 | return 0; |
3d083395 SR |
2701 | } |
2702 | ||
c88fd863 SR |
2703 | /** |
2704 | * ftrace_run_stop_machine, go back to the stop machine method | |
2705 | * @command: The command to tell ftrace what to do | |
2706 | * | |
2707 | * If an arch needs to fall back to the stop machine method, the | |
2708 | * it can call this function. | |
2709 | */ | |
2710 | void ftrace_run_stop_machine(int command) | |
2711 | { | |
2712 | stop_machine(__ftrace_modify_code, &command, NULL); | |
2713 | } | |
2714 | ||
2715 | /** | |
2716 | * arch_ftrace_update_code, modify the code to trace or not trace | |
2717 | * @command: The command that needs to be done | |
2718 | * | |
2719 | * Archs can override this function if it does not need to | |
2720 | * run stop_machine() to modify code. | |
2721 | */ | |
2722 | void __weak arch_ftrace_update_code(int command) | |
2723 | { | |
2724 | ftrace_run_stop_machine(command); | |
2725 | } | |
2726 | ||
e309b41d | 2727 | static void ftrace_run_update_code(int command) |
3d083395 | 2728 | { |
000ab691 SR |
2729 | int ret; |
2730 | ||
2731 | ret = ftrace_arch_code_modify_prepare(); | |
2732 | FTRACE_WARN_ON(ret); | |
2733 | if (ret) | |
d5b844a2 | 2734 | return; |
000ab691 | 2735 | |
c88fd863 SR |
2736 | /* |
2737 | * By default we use stop_machine() to modify the code. | |
2738 | * But archs can do what ever they want as long as it | |
2739 | * is safe. The stop_machine() is the safest, but also | |
2740 | * produces the most overhead. | |
2741 | */ | |
2742 | arch_ftrace_update_code(command); | |
2743 | ||
000ab691 SR |
2744 | ret = ftrace_arch_code_modify_post_process(); |
2745 | FTRACE_WARN_ON(ret); | |
3d083395 SR |
2746 | } |
2747 | ||
8252ecf3 | 2748 | static void ftrace_run_modify_code(struct ftrace_ops *ops, int command, |
7485058e | 2749 | struct ftrace_ops_hash *old_hash) |
e1effa01 SRRH |
2750 | { |
2751 | ops->flags |= FTRACE_OPS_FL_MODIFYING; | |
7485058e SRRH |
2752 | ops->old_hash.filter_hash = old_hash->filter_hash; |
2753 | ops->old_hash.notrace_hash = old_hash->notrace_hash; | |
e1effa01 | 2754 | ftrace_run_update_code(command); |
8252ecf3 | 2755 | ops->old_hash.filter_hash = NULL; |
7485058e | 2756 | ops->old_hash.notrace_hash = NULL; |
e1effa01 SRRH |
2757 | ops->flags &= ~FTRACE_OPS_FL_MODIFYING; |
2758 | } | |
2759 | ||
d61f82d0 | 2760 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 2761 | static int ftrace_start_up; |
df4fc315 | 2762 | |
12cce594 SRRH |
2763 | void __weak arch_ftrace_trampoline_free(struct ftrace_ops *ops) |
2764 | { | |
2765 | } | |
2766 | ||
df4fc315 SR |
2767 | static void ftrace_startup_enable(int command) |
2768 | { | |
2769 | if (saved_ftrace_func != ftrace_trace_function) { | |
2770 | saved_ftrace_func = ftrace_trace_function; | |
2771 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2772 | } | |
2773 | ||
2774 | if (!command || !ftrace_enabled) | |
2775 | return; | |
2776 | ||
2777 | ftrace_run_update_code(command); | |
2778 | } | |
d61f82d0 | 2779 | |
e1effa01 SRRH |
2780 | static void ftrace_startup_all(int command) |
2781 | { | |
2782 | update_all_ops = true; | |
2783 | ftrace_startup_enable(command); | |
2784 | update_all_ops = false; | |
2785 | } | |
2786 | ||
3306fc4a | 2787 | int ftrace_startup(struct ftrace_ops *ops, int command) |
3d083395 | 2788 | { |
8a56d776 | 2789 | int ret; |
b848914c | 2790 | |
4eebcc81 | 2791 | if (unlikely(ftrace_disabled)) |
a1cd6173 | 2792 | return -ENODEV; |
4eebcc81 | 2793 | |
8a56d776 SRRH |
2794 | ret = __register_ftrace_function(ops); |
2795 | if (ret) | |
2796 | return ret; | |
2797 | ||
60a7ecf4 | 2798 | ftrace_start_up++; |
d61f82d0 | 2799 | |
e1effa01 SRRH |
2800 | /* |
2801 | * Note that ftrace probes uses this to start up | |
2802 | * and modify functions it will probe. But we still | |
2803 | * set the ADDING flag for modification, as probes | |
2804 | * do not have trampolines. If they add them in the | |
2805 | * future, then the probes will need to distinguish | |
2806 | * between adding and updating probes. | |
2807 | */ | |
2808 | ops->flags |= FTRACE_OPS_FL_ENABLED | FTRACE_OPS_FL_ADDING; | |
66209a5b | 2809 | |
f8b8be8a MH |
2810 | ret = ftrace_hash_ipmodify_enable(ops); |
2811 | if (ret < 0) { | |
2812 | /* Rollback registration process */ | |
2813 | __unregister_ftrace_function(ops); | |
2814 | ftrace_start_up--; | |
2815 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; | |
2816 | return ret; | |
2817 | } | |
2818 | ||
7f50d06b JO |
2819 | if (ftrace_hash_rec_enable(ops, 1)) |
2820 | command |= FTRACE_UPDATE_CALLS; | |
ed926f9b | 2821 | |
df4fc315 | 2822 | ftrace_startup_enable(command); |
a1cd6173 | 2823 | |
e1effa01 SRRH |
2824 | ops->flags &= ~FTRACE_OPS_FL_ADDING; |
2825 | ||
a1cd6173 | 2826 | return 0; |
3d083395 SR |
2827 | } |
2828 | ||
3306fc4a | 2829 | int ftrace_shutdown(struct ftrace_ops *ops, int command) |
3d083395 | 2830 | { |
8a56d776 | 2831 | int ret; |
b848914c | 2832 | |
4eebcc81 | 2833 | if (unlikely(ftrace_disabled)) |
8a56d776 SRRH |
2834 | return -ENODEV; |
2835 | ||
2836 | ret = __unregister_ftrace_function(ops); | |
2837 | if (ret) | |
2838 | return ret; | |
4eebcc81 | 2839 | |
60a7ecf4 | 2840 | ftrace_start_up--; |
9ea1a153 FW |
2841 | /* |
2842 | * Just warn in case of unbalance, no need to kill ftrace, it's not | |
2843 | * critical but the ftrace_call callers may be never nopped again after | |
2844 | * further ftrace uses. | |
2845 | */ | |
2846 | WARN_ON_ONCE(ftrace_start_up < 0); | |
2847 | ||
f8b8be8a MH |
2848 | /* Disabling ipmodify never fails */ |
2849 | ftrace_hash_ipmodify_disable(ops); | |
ed926f9b | 2850 | |
7f50d06b JO |
2851 | if (ftrace_hash_rec_disable(ops, 1)) |
2852 | command |= FTRACE_UPDATE_CALLS; | |
b848914c | 2853 | |
7f50d06b | 2854 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; |
3d083395 | 2855 | |
d61f82d0 SR |
2856 | if (saved_ftrace_func != ftrace_trace_function) { |
2857 | saved_ftrace_func = ftrace_trace_function; | |
2858 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2859 | } | |
3d083395 | 2860 | |
a4c35ed2 SRRH |
2861 | if (!command || !ftrace_enabled) { |
2862 | /* | |
edb096e0 SRV |
2863 | * If these are dynamic or per_cpu ops, they still |
2864 | * need their data freed. Since, function tracing is | |
a4c35ed2 SRRH |
2865 | * not currently active, we can just free them |
2866 | * without synchronizing all CPUs. | |
2867 | */ | |
b3a88803 | 2868 | if (ops->flags & FTRACE_OPS_FL_DYNAMIC) |
edb096e0 SRV |
2869 | goto free_ops; |
2870 | ||
8a56d776 | 2871 | return 0; |
a4c35ed2 | 2872 | } |
d61f82d0 | 2873 | |
79922b80 SRRH |
2874 | /* |
2875 | * If the ops uses a trampoline, then it needs to be | |
2876 | * tested first on update. | |
2877 | */ | |
e1effa01 | 2878 | ops->flags |= FTRACE_OPS_FL_REMOVING; |
79922b80 SRRH |
2879 | removed_ops = ops; |
2880 | ||
fef5aeee SRRH |
2881 | /* The trampoline logic checks the old hashes */ |
2882 | ops->old_hash.filter_hash = ops->func_hash->filter_hash; | |
2883 | ops->old_hash.notrace_hash = ops->func_hash->notrace_hash; | |
2884 | ||
d61f82d0 | 2885 | ftrace_run_update_code(command); |
a4c35ed2 | 2886 | |
84bde62c SRRH |
2887 | /* |
2888 | * If there's no more ops registered with ftrace, run a | |
2889 | * sanity check to make sure all rec flags are cleared. | |
2890 | */ | |
f86f4180 CZ |
2891 | if (rcu_dereference_protected(ftrace_ops_list, |
2892 | lockdep_is_held(&ftrace_lock)) == &ftrace_list_end) { | |
84bde62c SRRH |
2893 | struct ftrace_page *pg; |
2894 | struct dyn_ftrace *rec; | |
2895 | ||
2896 | do_for_each_ftrace_rec(pg, rec) { | |
977c1f9c | 2897 | if (FTRACE_WARN_ON_ONCE(rec->flags & ~FTRACE_FL_DISABLED)) |
84bde62c SRRH |
2898 | pr_warn(" %pS flags:%lx\n", |
2899 | (void *)rec->ip, rec->flags); | |
2900 | } while_for_each_ftrace_rec(); | |
2901 | } | |
2902 | ||
fef5aeee SRRH |
2903 | ops->old_hash.filter_hash = NULL; |
2904 | ops->old_hash.notrace_hash = NULL; | |
2905 | ||
2906 | removed_ops = NULL; | |
e1effa01 | 2907 | ops->flags &= ~FTRACE_OPS_FL_REMOVING; |
79922b80 | 2908 | |
a4c35ed2 SRRH |
2909 | /* |
2910 | * Dynamic ops may be freed, we must make sure that all | |
2911 | * callers are done before leaving this function. | |
ba27f2bc | 2912 | * The same goes for freeing the per_cpu data of the per_cpu |
a4c35ed2 | 2913 | * ops. |
a4c35ed2 | 2914 | */ |
b3a88803 | 2915 | if (ops->flags & FTRACE_OPS_FL_DYNAMIC) { |
0598e4f0 SRV |
2916 | /* |
2917 | * We need to do a hard force of sched synchronization. | |
2918 | * This is because we use preempt_disable() to do RCU, but | |
2919 | * the function tracers can be called where RCU is not watching | |
2920 | * (like before user_exit()). We can not rely on the RCU | |
2921 | * infrastructure to do the synchronization, thus we must do it | |
2922 | * ourselves. | |
2923 | */ | |
e5a971d7 | 2924 | synchronize_rcu_tasks_rude(); |
a4c35ed2 | 2925 | |
0598e4f0 SRV |
2926 | /* |
2927 | * When the kernel is preeptive, tasks can be preempted | |
2928 | * while on a ftrace trampoline. Just scheduling a task on | |
2929 | * a CPU is not good enough to flush them. Calling | |
2930 | * synchornize_rcu_tasks() will wait for those tasks to | |
2931 | * execute and either schedule voluntarily or enter user space. | |
2932 | */ | |
30c93704 | 2933 | if (IS_ENABLED(CONFIG_PREEMPTION)) |
0598e4f0 SRV |
2934 | synchronize_rcu_tasks(); |
2935 | ||
edb096e0 | 2936 | free_ops: |
12cce594 | 2937 | arch_ftrace_trampoline_free(ops); |
a4c35ed2 SRRH |
2938 | } |
2939 | ||
8a56d776 | 2940 | return 0; |
3d083395 SR |
2941 | } |
2942 | ||
e309b41d | 2943 | static void ftrace_startup_sysctl(void) |
b0fc494f | 2944 | { |
1619dc3f PA |
2945 | int command; |
2946 | ||
4eebcc81 SR |
2947 | if (unlikely(ftrace_disabled)) |
2948 | return; | |
2949 | ||
d61f82d0 SR |
2950 | /* Force update next time */ |
2951 | saved_ftrace_func = NULL; | |
60a7ecf4 | 2952 | /* ftrace_start_up is true if we want ftrace running */ |
1619dc3f PA |
2953 | if (ftrace_start_up) { |
2954 | command = FTRACE_UPDATE_CALLS; | |
2955 | if (ftrace_graph_active) | |
2956 | command |= FTRACE_START_FUNC_RET; | |
524a3868 | 2957 | ftrace_startup_enable(command); |
1619dc3f | 2958 | } |
b0fc494f SR |
2959 | } |
2960 | ||
e309b41d | 2961 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 2962 | { |
1619dc3f PA |
2963 | int command; |
2964 | ||
4eebcc81 SR |
2965 | if (unlikely(ftrace_disabled)) |
2966 | return; | |
2967 | ||
60a7ecf4 | 2968 | /* ftrace_start_up is true if ftrace is running */ |
1619dc3f PA |
2969 | if (ftrace_start_up) { |
2970 | command = FTRACE_DISABLE_CALLS; | |
2971 | if (ftrace_graph_active) | |
2972 | command |= FTRACE_STOP_FUNC_RET; | |
2973 | ftrace_run_update_code(command); | |
2974 | } | |
b0fc494f SR |
2975 | } |
2976 | ||
a5a1d1c2 | 2977 | static u64 ftrace_update_time; |
3d083395 | 2978 | unsigned long ftrace_update_tot_cnt; |
da537f0a SRV |
2979 | unsigned long ftrace_number_of_pages; |
2980 | unsigned long ftrace_number_of_groups; | |
3d083395 | 2981 | |
8c4f3c3f | 2982 | static inline int ops_traces_mod(struct ftrace_ops *ops) |
f7bc8b61 | 2983 | { |
8c4f3c3f SRRH |
2984 | /* |
2985 | * Filter_hash being empty will default to trace module. | |
2986 | * But notrace hash requires a test of individual module functions. | |
2987 | */ | |
33b7f99c SRRH |
2988 | return ftrace_hash_empty(ops->func_hash->filter_hash) && |
2989 | ftrace_hash_empty(ops->func_hash->notrace_hash); | |
8c4f3c3f SRRH |
2990 | } |
2991 | ||
2992 | /* | |
2993 | * Check if the current ops references the record. | |
2994 | * | |
2995 | * If the ops traces all functions, then it was already accounted for. | |
2996 | * If the ops does not trace the current record function, skip it. | |
2997 | * If the ops ignores the function via notrace filter, skip it. | |
2998 | */ | |
2999 | static inline bool | |
3000 | ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec) | |
3001 | { | |
3002 | /* If ops isn't enabled, ignore it */ | |
3003 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
44ec3ec0 | 3004 | return false; |
8c4f3c3f | 3005 | |
b7ffffbb | 3006 | /* If ops traces all then it includes this function */ |
8c4f3c3f | 3007 | if (ops_traces_mod(ops)) |
44ec3ec0 | 3008 | return true; |
8c4f3c3f SRRH |
3009 | |
3010 | /* The function must be in the filter */ | |
33b7f99c | 3011 | if (!ftrace_hash_empty(ops->func_hash->filter_hash) && |
2b2c279c | 3012 | !__ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip)) |
44ec3ec0 | 3013 | return false; |
f7bc8b61 | 3014 | |
8c4f3c3f | 3015 | /* If in notrace hash, we ignore it too */ |
33b7f99c | 3016 | if (ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip)) |
44ec3ec0 | 3017 | return false; |
8c4f3c3f | 3018 | |
44ec3ec0 | 3019 | return true; |
8c4f3c3f SRRH |
3020 | } |
3021 | ||
1dc43cf0 | 3022 | static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs) |
3d083395 | 3023 | { |
85ae32ae | 3024 | struct ftrace_page *pg; |
e94142a6 | 3025 | struct dyn_ftrace *p; |
a5a1d1c2 | 3026 | u64 start, stop; |
1dc43cf0 | 3027 | unsigned long update_cnt = 0; |
b7ffffbb | 3028 | unsigned long rec_flags = 0; |
85ae32ae | 3029 | int i; |
f7bc8b61 | 3030 | |
b7ffffbb SRRH |
3031 | start = ftrace_now(raw_smp_processor_id()); |
3032 | ||
f7bc8b61 | 3033 | /* |
b7ffffbb SRRH |
3034 | * When a module is loaded, this function is called to convert |
3035 | * the calls to mcount in its text to nops, and also to create | |
3036 | * an entry in the ftrace data. Now, if ftrace is activated | |
3037 | * after this call, but before the module sets its text to | |
3038 | * read-only, the modification of enabling ftrace can fail if | |
3039 | * the read-only is done while ftrace is converting the calls. | |
3040 | * To prevent this, the module's records are set as disabled | |
3041 | * and will be enabled after the call to set the module's text | |
3042 | * to read-only. | |
f7bc8b61 | 3043 | */ |
b7ffffbb SRRH |
3044 | if (mod) |
3045 | rec_flags |= FTRACE_FL_DISABLED; | |
3d083395 | 3046 | |
1dc43cf0 | 3047 | for (pg = new_pgs; pg; pg = pg->next) { |
3d083395 | 3048 | |
85ae32ae | 3049 | for (i = 0; i < pg->index; i++) { |
8c4f3c3f | 3050 | |
85ae32ae SR |
3051 | /* If something went wrong, bail without enabling anything */ |
3052 | if (unlikely(ftrace_disabled)) | |
3053 | return -1; | |
f22f9a89 | 3054 | |
85ae32ae | 3055 | p = &pg->records[i]; |
b7ffffbb | 3056 | p->flags = rec_flags; |
f22f9a89 | 3057 | |
85ae32ae SR |
3058 | /* |
3059 | * Do the initial record conversion from mcount jump | |
3060 | * to the NOP instructions. | |
3061 | */ | |
cbdaeaf0 | 3062 | if (!__is_defined(CC_USING_NOP_MCOUNT) && |
fbf6c73c | 3063 | !ftrace_nop_initialize(mod, p)) |
85ae32ae | 3064 | break; |
5cb084bb | 3065 | |
1dc43cf0 | 3066 | update_cnt++; |
5cb084bb | 3067 | } |
3d083395 SR |
3068 | } |
3069 | ||
750ed1a4 | 3070 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 | 3071 | ftrace_update_time = stop - start; |
1dc43cf0 | 3072 | ftrace_update_tot_cnt += update_cnt; |
3d083395 | 3073 | |
16444a8a ACM |
3074 | return 0; |
3075 | } | |
3076 | ||
a7900875 | 3077 | static int ftrace_allocate_records(struct ftrace_page *pg, int count) |
3c1720f0 | 3078 | { |
a7900875 | 3079 | int order; |
3c1720f0 | 3080 | int cnt; |
3c1720f0 | 3081 | |
a7900875 SR |
3082 | if (WARN_ON(!count)) |
3083 | return -EINVAL; | |
3084 | ||
3085 | order = get_count_order(DIV_ROUND_UP(count, ENTRIES_PER_PAGE)); | |
3c1720f0 SR |
3086 | |
3087 | /* | |
a7900875 SR |
3088 | * We want to fill as much as possible. No more than a page |
3089 | * may be empty. | |
3c1720f0 | 3090 | */ |
a7900875 SR |
3091 | while ((PAGE_SIZE << order) / ENTRY_SIZE >= count + ENTRIES_PER_PAGE) |
3092 | order--; | |
3c1720f0 | 3093 | |
a7900875 SR |
3094 | again: |
3095 | pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); | |
3c1720f0 | 3096 | |
a7900875 SR |
3097 | if (!pg->records) { |
3098 | /* if we can't allocate this size, try something smaller */ | |
3099 | if (!order) | |
3100 | return -ENOMEM; | |
3101 | order >>= 1; | |
3102 | goto again; | |
3103 | } | |
3c1720f0 | 3104 | |
da537f0a SRV |
3105 | ftrace_number_of_pages += 1 << order; |
3106 | ftrace_number_of_groups++; | |
3107 | ||
a7900875 SR |
3108 | cnt = (PAGE_SIZE << order) / ENTRY_SIZE; |
3109 | pg->size = cnt; | |
3c1720f0 | 3110 | |
a7900875 SR |
3111 | if (cnt > count) |
3112 | cnt = count; | |
3113 | ||
3114 | return cnt; | |
3115 | } | |
3116 | ||
3117 | static struct ftrace_page * | |
3118 | ftrace_allocate_pages(unsigned long num_to_init) | |
3119 | { | |
3120 | struct ftrace_page *start_pg; | |
3121 | struct ftrace_page *pg; | |
3122 | int order; | |
3123 | int cnt; | |
3124 | ||
3125 | if (!num_to_init) | |
9efb85c5 | 3126 | return NULL; |
a7900875 SR |
3127 | |
3128 | start_pg = pg = kzalloc(sizeof(*pg), GFP_KERNEL); | |
3129 | if (!pg) | |
3130 | return NULL; | |
3131 | ||
3132 | /* | |
3133 | * Try to allocate as much as possible in one continues | |
3134 | * location that fills in all of the space. We want to | |
3135 | * waste as little space as possible. | |
3136 | */ | |
3137 | for (;;) { | |
3138 | cnt = ftrace_allocate_records(pg, num_to_init); | |
3139 | if (cnt < 0) | |
3140 | goto free_pages; | |
3141 | ||
3142 | num_to_init -= cnt; | |
3143 | if (!num_to_init) | |
3c1720f0 SR |
3144 | break; |
3145 | ||
a7900875 SR |
3146 | pg->next = kzalloc(sizeof(*pg), GFP_KERNEL); |
3147 | if (!pg->next) | |
3148 | goto free_pages; | |
3149 | ||
3c1720f0 SR |
3150 | pg = pg->next; |
3151 | } | |
3152 | ||
a7900875 SR |
3153 | return start_pg; |
3154 | ||
3155 | free_pages: | |
1f61be00 NK |
3156 | pg = start_pg; |
3157 | while (pg) { | |
a7900875 SR |
3158 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); |
3159 | free_pages((unsigned long)pg->records, order); | |
3160 | start_pg = pg->next; | |
3161 | kfree(pg); | |
3162 | pg = start_pg; | |
da537f0a SRV |
3163 | ftrace_number_of_pages -= 1 << order; |
3164 | ftrace_number_of_groups--; | |
a7900875 SR |
3165 | } |
3166 | pr_info("ftrace: FAILED to allocate memory for functions\n"); | |
3167 | return NULL; | |
3168 | } | |
3169 | ||
5072c59f SR |
3170 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ |
3171 | ||
3172 | struct ftrace_iterator { | |
98c4fd04 | 3173 | loff_t pos; |
4aeb6967 | 3174 | loff_t func_pos; |
5985ea8b | 3175 | loff_t mod_pos; |
4aeb6967 SR |
3176 | struct ftrace_page *pg; |
3177 | struct dyn_ftrace *func; | |
3178 | struct ftrace_func_probe *probe; | |
eee8ded1 | 3179 | struct ftrace_func_entry *probe_entry; |
4aeb6967 | 3180 | struct trace_parser parser; |
1cf41dd7 | 3181 | struct ftrace_hash *hash; |
33dc9b12 | 3182 | struct ftrace_ops *ops; |
5985ea8b SRV |
3183 | struct trace_array *tr; |
3184 | struct list_head *mod_list; | |
eee8ded1 | 3185 | int pidx; |
4aeb6967 SR |
3186 | int idx; |
3187 | unsigned flags; | |
5072c59f SR |
3188 | }; |
3189 | ||
8fc0c701 | 3190 | static void * |
eee8ded1 | 3191 | t_probe_next(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
3192 | { |
3193 | struct ftrace_iterator *iter = m->private; | |
d2afd57a | 3194 | struct trace_array *tr = iter->ops->private; |
04ec7bb6 | 3195 | struct list_head *func_probes; |
eee8ded1 SRV |
3196 | struct ftrace_hash *hash; |
3197 | struct list_head *next; | |
4aeb6967 | 3198 | struct hlist_node *hnd = NULL; |
8fc0c701 | 3199 | struct hlist_head *hhd; |
eee8ded1 | 3200 | int size; |
8fc0c701 | 3201 | |
8fc0c701 | 3202 | (*pos)++; |
98c4fd04 | 3203 | iter->pos = *pos; |
8fc0c701 | 3204 | |
04ec7bb6 | 3205 | if (!tr) |
8fc0c701 SR |
3206 | return NULL; |
3207 | ||
04ec7bb6 SRV |
3208 | func_probes = &tr->func_probes; |
3209 | if (list_empty(func_probes)) | |
8fc0c701 SR |
3210 | return NULL; |
3211 | ||
eee8ded1 | 3212 | if (!iter->probe) { |
04ec7bb6 | 3213 | next = func_probes->next; |
7b60f3d8 | 3214 | iter->probe = list_entry(next, struct ftrace_func_probe, list); |
eee8ded1 SRV |
3215 | } |
3216 | ||
3217 | if (iter->probe_entry) | |
3218 | hnd = &iter->probe_entry->hlist; | |
3219 | ||
3220 | hash = iter->probe->ops.func_hash->filter_hash; | |
7bd46644 | 3221 | |
372e0d01 SRV |
3222 | /* |
3223 | * A probe being registered may temporarily have an empty hash | |
3224 | * and it's at the end of the func_probes list. | |
3225 | */ | |
3226 | if (!hash || hash == EMPTY_HASH) | |
7bd46644 NR |
3227 | return NULL; |
3228 | ||
eee8ded1 SRV |
3229 | size = 1 << hash->size_bits; |
3230 | ||
3231 | retry: | |
3232 | if (iter->pidx >= size) { | |
04ec7bb6 | 3233 | if (iter->probe->list.next == func_probes) |
eee8ded1 SRV |
3234 | return NULL; |
3235 | next = iter->probe->list.next; | |
7b60f3d8 | 3236 | iter->probe = list_entry(next, struct ftrace_func_probe, list); |
eee8ded1 SRV |
3237 | hash = iter->probe->ops.func_hash->filter_hash; |
3238 | size = 1 << hash->size_bits; | |
3239 | iter->pidx = 0; | |
3240 | } | |
3241 | ||
3242 | hhd = &hash->buckets[iter->pidx]; | |
8fc0c701 SR |
3243 | |
3244 | if (hlist_empty(hhd)) { | |
eee8ded1 | 3245 | iter->pidx++; |
8fc0c701 SR |
3246 | hnd = NULL; |
3247 | goto retry; | |
3248 | } | |
3249 | ||
3250 | if (!hnd) | |
3251 | hnd = hhd->first; | |
3252 | else { | |
3253 | hnd = hnd->next; | |
3254 | if (!hnd) { | |
eee8ded1 | 3255 | iter->pidx++; |
8fc0c701 SR |
3256 | goto retry; |
3257 | } | |
3258 | } | |
3259 | ||
4aeb6967 SR |
3260 | if (WARN_ON_ONCE(!hnd)) |
3261 | return NULL; | |
3262 | ||
eee8ded1 | 3263 | iter->probe_entry = hlist_entry(hnd, struct ftrace_func_entry, hlist); |
4aeb6967 SR |
3264 | |
3265 | return iter; | |
8fc0c701 SR |
3266 | } |
3267 | ||
eee8ded1 | 3268 | static void *t_probe_start(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
3269 | { |
3270 | struct ftrace_iterator *iter = m->private; | |
3271 | void *p = NULL; | |
d82d6244 LZ |
3272 | loff_t l; |
3273 | ||
eee8ded1 | 3274 | if (!(iter->flags & FTRACE_ITER_DO_PROBES)) |
69a3083c SR |
3275 | return NULL; |
3276 | ||
5985ea8b | 3277 | if (iter->mod_pos > *pos) |
2bccfffd | 3278 | return NULL; |
8fc0c701 | 3279 | |
eee8ded1 SRV |
3280 | iter->probe = NULL; |
3281 | iter->probe_entry = NULL; | |
3282 | iter->pidx = 0; | |
5985ea8b | 3283 | for (l = 0; l <= (*pos - iter->mod_pos); ) { |
eee8ded1 | 3284 | p = t_probe_next(m, &l); |
d82d6244 LZ |
3285 | if (!p) |
3286 | break; | |
3287 | } | |
4aeb6967 SR |
3288 | if (!p) |
3289 | return NULL; | |
3290 | ||
98c4fd04 | 3291 | /* Only set this if we have an item */ |
eee8ded1 | 3292 | iter->flags |= FTRACE_ITER_PROBE; |
98c4fd04 | 3293 | |
4aeb6967 | 3294 | return iter; |
8fc0c701 SR |
3295 | } |
3296 | ||
4aeb6967 | 3297 | static int |
eee8ded1 | 3298 | t_probe_show(struct seq_file *m, struct ftrace_iterator *iter) |
8fc0c701 | 3299 | { |
eee8ded1 | 3300 | struct ftrace_func_entry *probe_entry; |
7b60f3d8 SRV |
3301 | struct ftrace_probe_ops *probe_ops; |
3302 | struct ftrace_func_probe *probe; | |
8fc0c701 | 3303 | |
eee8ded1 SRV |
3304 | probe = iter->probe; |
3305 | probe_entry = iter->probe_entry; | |
8fc0c701 | 3306 | |
eee8ded1 | 3307 | if (WARN_ON_ONCE(!probe || !probe_entry)) |
4aeb6967 | 3308 | return -EIO; |
8fc0c701 | 3309 | |
7b60f3d8 | 3310 | probe_ops = probe->probe_ops; |
809dcf29 | 3311 | |
7b60f3d8 | 3312 | if (probe_ops->print) |
6e444319 | 3313 | return probe_ops->print(m, probe_entry->ip, probe_ops, probe->data); |
8fc0c701 | 3314 | |
7b60f3d8 SRV |
3315 | seq_printf(m, "%ps:%ps\n", (void *)probe_entry->ip, |
3316 | (void *)probe_ops->func); | |
8fc0c701 SR |
3317 | |
3318 | return 0; | |
3319 | } | |
3320 | ||
5985ea8b SRV |
3321 | static void * |
3322 | t_mod_next(struct seq_file *m, loff_t *pos) | |
3323 | { | |
3324 | struct ftrace_iterator *iter = m->private; | |
3325 | struct trace_array *tr = iter->tr; | |
3326 | ||
3327 | (*pos)++; | |
3328 | iter->pos = *pos; | |
3329 | ||
3330 | iter->mod_list = iter->mod_list->next; | |
3331 | ||
3332 | if (iter->mod_list == &tr->mod_trace || | |
3333 | iter->mod_list == &tr->mod_notrace) { | |
3334 | iter->flags &= ~FTRACE_ITER_MOD; | |
3335 | return NULL; | |
3336 | } | |
3337 | ||
3338 | iter->mod_pos = *pos; | |
3339 | ||
3340 | return iter; | |
3341 | } | |
3342 | ||
3343 | static void *t_mod_start(struct seq_file *m, loff_t *pos) | |
3344 | { | |
3345 | struct ftrace_iterator *iter = m->private; | |
3346 | void *p = NULL; | |
3347 | loff_t l; | |
3348 | ||
3349 | if (iter->func_pos > *pos) | |
3350 | return NULL; | |
3351 | ||
3352 | iter->mod_pos = iter->func_pos; | |
3353 | ||
3354 | /* probes are only available if tr is set */ | |
3355 | if (!iter->tr) | |
3356 | return NULL; | |
3357 | ||
3358 | for (l = 0; l <= (*pos - iter->func_pos); ) { | |
3359 | p = t_mod_next(m, &l); | |
3360 | if (!p) | |
3361 | break; | |
3362 | } | |
3363 | if (!p) { | |
3364 | iter->flags &= ~FTRACE_ITER_MOD; | |
3365 | return t_probe_start(m, pos); | |
3366 | } | |
3367 | ||
3368 | /* Only set this if we have an item */ | |
3369 | iter->flags |= FTRACE_ITER_MOD; | |
3370 | ||
3371 | return iter; | |
3372 | } | |
3373 | ||
3374 | static int | |
3375 | t_mod_show(struct seq_file *m, struct ftrace_iterator *iter) | |
3376 | { | |
3377 | struct ftrace_mod_load *ftrace_mod; | |
3378 | struct trace_array *tr = iter->tr; | |
3379 | ||
3380 | if (WARN_ON_ONCE(!iter->mod_list) || | |
3381 | iter->mod_list == &tr->mod_trace || | |
3382 | iter->mod_list == &tr->mod_notrace) | |
3383 | return -EIO; | |
3384 | ||
3385 | ftrace_mod = list_entry(iter->mod_list, struct ftrace_mod_load, list); | |
3386 | ||
3387 | if (ftrace_mod->func) | |
3388 | seq_printf(m, "%s", ftrace_mod->func); | |
3389 | else | |
3390 | seq_putc(m, '*'); | |
3391 | ||
3392 | seq_printf(m, ":mod:%s\n", ftrace_mod->module); | |
3393 | ||
3394 | return 0; | |
3395 | } | |
3396 | ||
e309b41d | 3397 | static void * |
5bd84629 | 3398 | t_func_next(struct seq_file *m, loff_t *pos) |
5072c59f SR |
3399 | { |
3400 | struct ftrace_iterator *iter = m->private; | |
3401 | struct dyn_ftrace *rec = NULL; | |
3402 | ||
3403 | (*pos)++; | |
0c75a3ed | 3404 | |
5072c59f SR |
3405 | retry: |
3406 | if (iter->idx >= iter->pg->index) { | |
3407 | if (iter->pg->next) { | |
3408 | iter->pg = iter->pg->next; | |
3409 | iter->idx = 0; | |
3410 | goto retry; | |
3411 | } | |
3412 | } else { | |
3413 | rec = &iter->pg->records[iter->idx++]; | |
c20489da SRV |
3414 | if (((iter->flags & (FTRACE_ITER_FILTER | FTRACE_ITER_NOTRACE)) && |
3415 | !ftrace_lookup_ip(iter->hash, rec->ip)) || | |
647bcd03 SR |
3416 | |
3417 | ((iter->flags & FTRACE_ITER_ENABLED) && | |
23ea9c4d | 3418 | !(rec->flags & FTRACE_FL_ENABLED))) { |
647bcd03 | 3419 | |
5072c59f SR |
3420 | rec = NULL; |
3421 | goto retry; | |
3422 | } | |
3423 | } | |
3424 | ||
4aeb6967 | 3425 | if (!rec) |
5bd84629 | 3426 | return NULL; |
4aeb6967 | 3427 | |
5bd84629 | 3428 | iter->pos = iter->func_pos = *pos; |
4aeb6967 SR |
3429 | iter->func = rec; |
3430 | ||
3431 | return iter; | |
5072c59f SR |
3432 | } |
3433 | ||
5bd84629 SRV |
3434 | static void * |
3435 | t_next(struct seq_file *m, void *v, loff_t *pos) | |
3436 | { | |
3437 | struct ftrace_iterator *iter = m->private; | |
5985ea8b | 3438 | loff_t l = *pos; /* t_probe_start() must use original pos */ |
5bd84629 SRV |
3439 | void *ret; |
3440 | ||
3441 | if (unlikely(ftrace_disabled)) | |
3442 | return NULL; | |
3443 | ||
eee8ded1 SRV |
3444 | if (iter->flags & FTRACE_ITER_PROBE) |
3445 | return t_probe_next(m, pos); | |
5bd84629 | 3446 | |
5985ea8b SRV |
3447 | if (iter->flags & FTRACE_ITER_MOD) |
3448 | return t_mod_next(m, pos); | |
3449 | ||
5bd84629 | 3450 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
eee8ded1 | 3451 | /* next must increment pos, and t_probe_start does not */ |
5bd84629 | 3452 | (*pos)++; |
5985ea8b | 3453 | return t_mod_start(m, &l); |
5bd84629 SRV |
3454 | } |
3455 | ||
3456 | ret = t_func_next(m, pos); | |
3457 | ||
3458 | if (!ret) | |
5985ea8b | 3459 | return t_mod_start(m, &l); |
5bd84629 SRV |
3460 | |
3461 | return ret; | |
3462 | } | |
3463 | ||
98c4fd04 SR |
3464 | static void reset_iter_read(struct ftrace_iterator *iter) |
3465 | { | |
3466 | iter->pos = 0; | |
3467 | iter->func_pos = 0; | |
5985ea8b | 3468 | iter->flags &= ~(FTRACE_ITER_PRINTALL | FTRACE_ITER_PROBE | FTRACE_ITER_MOD); |
5072c59f SR |
3469 | } |
3470 | ||
3471 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3472 | { | |
3473 | struct ftrace_iterator *iter = m->private; | |
3474 | void *p = NULL; | |
694ce0a5 | 3475 | loff_t l; |
5072c59f | 3476 | |
8fc0c701 | 3477 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
3478 | |
3479 | if (unlikely(ftrace_disabled)) | |
3480 | return NULL; | |
3481 | ||
98c4fd04 SR |
3482 | /* |
3483 | * If an lseek was done, then reset and start from beginning. | |
3484 | */ | |
3485 | if (*pos < iter->pos) | |
3486 | reset_iter_read(iter); | |
3487 | ||
0c75a3ed SR |
3488 | /* |
3489 | * For set_ftrace_filter reading, if we have the filter | |
3490 | * off, we can short cut and just print out that all | |
3491 | * functions are enabled. | |
3492 | */ | |
c20489da SRV |
3493 | if ((iter->flags & (FTRACE_ITER_FILTER | FTRACE_ITER_NOTRACE)) && |
3494 | ftrace_hash_empty(iter->hash)) { | |
43ff926a | 3495 | iter->func_pos = 1; /* Account for the message */ |
0c75a3ed | 3496 | if (*pos > 0) |
5985ea8b | 3497 | return t_mod_start(m, pos); |
0c75a3ed | 3498 | iter->flags |= FTRACE_ITER_PRINTALL; |
df091625 | 3499 | /* reset in case of seek/pread */ |
eee8ded1 | 3500 | iter->flags &= ~FTRACE_ITER_PROBE; |
0c75a3ed SR |
3501 | return iter; |
3502 | } | |
3503 | ||
5985ea8b SRV |
3504 | if (iter->flags & FTRACE_ITER_MOD) |
3505 | return t_mod_start(m, pos); | |
8fc0c701 | 3506 | |
98c4fd04 SR |
3507 | /* |
3508 | * Unfortunately, we need to restart at ftrace_pages_start | |
3509 | * every time we let go of the ftrace_mutex. This is because | |
3510 | * those pointers can change without the lock. | |
3511 | */ | |
694ce0a5 LZ |
3512 | iter->pg = ftrace_pages_start; |
3513 | iter->idx = 0; | |
3514 | for (l = 0; l <= *pos; ) { | |
5bd84629 | 3515 | p = t_func_next(m, &l); |
694ce0a5 LZ |
3516 | if (!p) |
3517 | break; | |
50cdaf08 | 3518 | } |
5821e1b7 | 3519 | |
69a3083c | 3520 | if (!p) |
5985ea8b | 3521 | return t_mod_start(m, pos); |
4aeb6967 SR |
3522 | |
3523 | return iter; | |
5072c59f SR |
3524 | } |
3525 | ||
3526 | static void t_stop(struct seq_file *m, void *p) | |
3527 | { | |
8fc0c701 | 3528 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
3529 | } |
3530 | ||
15d5b02c SRRH |
3531 | void * __weak |
3532 | arch_ftrace_trampoline_func(struct ftrace_ops *ops, struct dyn_ftrace *rec) | |
3533 | { | |
3534 | return NULL; | |
3535 | } | |
3536 | ||
3537 | static void add_trampoline_func(struct seq_file *m, struct ftrace_ops *ops, | |
3538 | struct dyn_ftrace *rec) | |
3539 | { | |
3540 | void *ptr; | |
3541 | ||
3542 | ptr = arch_ftrace_trampoline_func(ops, rec); | |
3543 | if (ptr) | |
3544 | seq_printf(m, " ->%pS", ptr); | |
3545 | } | |
3546 | ||
5072c59f SR |
3547 | static int t_show(struct seq_file *m, void *v) |
3548 | { | |
0c75a3ed | 3549 | struct ftrace_iterator *iter = m->private; |
4aeb6967 | 3550 | struct dyn_ftrace *rec; |
5072c59f | 3551 | |
eee8ded1 SRV |
3552 | if (iter->flags & FTRACE_ITER_PROBE) |
3553 | return t_probe_show(m, iter); | |
8fc0c701 | 3554 | |
5985ea8b SRV |
3555 | if (iter->flags & FTRACE_ITER_MOD) |
3556 | return t_mod_show(m, iter); | |
3557 | ||
0c75a3ed | 3558 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
8c006cf7 | 3559 | if (iter->flags & FTRACE_ITER_NOTRACE) |
fa6f0cc7 | 3560 | seq_puts(m, "#### no functions disabled ####\n"); |
8c006cf7 | 3561 | else |
fa6f0cc7 | 3562 | seq_puts(m, "#### all functions enabled ####\n"); |
0c75a3ed SR |
3563 | return 0; |
3564 | } | |
3565 | ||
4aeb6967 SR |
3566 | rec = iter->func; |
3567 | ||
5072c59f SR |
3568 | if (!rec) |
3569 | return 0; | |
3570 | ||
647bcd03 | 3571 | seq_printf(m, "%ps", (void *)rec->ip); |
9674b2fa | 3572 | if (iter->flags & FTRACE_ITER_ENABLED) { |
030f4e1c | 3573 | struct ftrace_ops *ops; |
15d5b02c | 3574 | |
763e34e7 | 3575 | seq_printf(m, " (%ld)%s%s%s", |
0376bde1 | 3576 | ftrace_rec_count(rec), |
f8b8be8a | 3577 | rec->flags & FTRACE_FL_REGS ? " R" : " ", |
763e34e7 SRV |
3578 | rec->flags & FTRACE_FL_IPMODIFY ? " I" : " ", |
3579 | rec->flags & FTRACE_FL_DIRECT ? " D" : " "); | |
9674b2fa | 3580 | if (rec->flags & FTRACE_FL_TRAMP_EN) { |
5fecaa04 | 3581 | ops = ftrace_find_tramp_ops_any(rec); |
39daa7b9 SRRH |
3582 | if (ops) { |
3583 | do { | |
3584 | seq_printf(m, "\ttramp: %pS (%pS)", | |
3585 | (void *)ops->trampoline, | |
3586 | (void *)ops->func); | |
030f4e1c | 3587 | add_trampoline_func(m, ops, rec); |
39daa7b9 SRRH |
3588 | ops = ftrace_find_tramp_ops_next(rec, ops); |
3589 | } while (ops); | |
3590 | } else | |
fa6f0cc7 | 3591 | seq_puts(m, "\ttramp: ERROR!"); |
030f4e1c SRRH |
3592 | } else { |
3593 | add_trampoline_func(m, NULL, rec); | |
9674b2fa | 3594 | } |
763e34e7 SRV |
3595 | if (rec->flags & FTRACE_FL_DIRECT) { |
3596 | unsigned long direct; | |
3597 | ||
ff205766 | 3598 | direct = ftrace_find_rec_direct(rec->ip); |
763e34e7 SRV |
3599 | if (direct) |
3600 | seq_printf(m, "\n\tdirect-->%pS", (void *)direct); | |
3601 | } | |
9674b2fa SRRH |
3602 | } |
3603 | ||
fa6f0cc7 | 3604 | seq_putc(m, '\n'); |
5072c59f SR |
3605 | |
3606 | return 0; | |
3607 | } | |
3608 | ||
88e9d34c | 3609 | static const struct seq_operations show_ftrace_seq_ops = { |
5072c59f SR |
3610 | .start = t_start, |
3611 | .next = t_next, | |
3612 | .stop = t_stop, | |
3613 | .show = t_show, | |
3614 | }; | |
3615 | ||
e309b41d | 3616 | static int |
5072c59f SR |
3617 | ftrace_avail_open(struct inode *inode, struct file *file) |
3618 | { | |
3619 | struct ftrace_iterator *iter; | |
17911ff3 SRV |
3620 | int ret; |
3621 | ||
3622 | ret = security_locked_down(LOCKDOWN_TRACEFS); | |
3623 | if (ret) | |
3624 | return ret; | |
5072c59f | 3625 | |
4eebcc81 SR |
3626 | if (unlikely(ftrace_disabled)) |
3627 | return -ENODEV; | |
3628 | ||
50e18b94 | 3629 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
c1bc5919 SRV |
3630 | if (!iter) |
3631 | return -ENOMEM; | |
5072c59f | 3632 | |
c1bc5919 SRV |
3633 | iter->pg = ftrace_pages_start; |
3634 | iter->ops = &global_ops; | |
3635 | ||
3636 | return 0; | |
5072c59f SR |
3637 | } |
3638 | ||
647bcd03 SR |
3639 | static int |
3640 | ftrace_enabled_open(struct inode *inode, struct file *file) | |
3641 | { | |
3642 | struct ftrace_iterator *iter; | |
647bcd03 | 3643 | |
17911ff3 SRV |
3644 | /* |
3645 | * This shows us what functions are currently being | |
3646 | * traced and by what. Not sure if we want lockdown | |
3647 | * to hide such critical information for an admin. | |
3648 | * Although, perhaps it can show information we don't | |
3649 | * want people to see, but if something is tracing | |
3650 | * something, we probably want to know about it. | |
3651 | */ | |
3652 | ||
50e18b94 | 3653 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
c1bc5919 SRV |
3654 | if (!iter) |
3655 | return -ENOMEM; | |
647bcd03 | 3656 | |
c1bc5919 SRV |
3657 | iter->pg = ftrace_pages_start; |
3658 | iter->flags = FTRACE_ITER_ENABLED; | |
3659 | iter->ops = &global_ops; | |
3660 | ||
3661 | return 0; | |
647bcd03 SR |
3662 | } |
3663 | ||
fc13cb0c SR |
3664 | /** |
3665 | * ftrace_regex_open - initialize function tracer filter files | |
3666 | * @ops: The ftrace_ops that hold the hash filters | |
3667 | * @flag: The type of filter to process | |
3668 | * @inode: The inode, usually passed in to your open routine | |
3669 | * @file: The file, usually passed in to your open routine | |
3670 | * | |
3671 | * ftrace_regex_open() initializes the filter files for the | |
3672 | * @ops. Depending on @flag it may process the filter hash or | |
3673 | * the notrace hash of @ops. With this called from the open | |
3674 | * routine, you can use ftrace_filter_write() for the write | |
3675 | * routine if @flag has FTRACE_ITER_FILTER set, or | |
3676 | * ftrace_notrace_write() if @flag has FTRACE_ITER_NOTRACE set. | |
098c879e | 3677 | * tracing_lseek() should be used as the lseek routine, and |
fc13cb0c SR |
3678 | * release must call ftrace_regex_release(). |
3679 | */ | |
3680 | int | |
f45948e8 | 3681 | ftrace_regex_open(struct ftrace_ops *ops, int flag, |
1cf41dd7 | 3682 | struct inode *inode, struct file *file) |
5072c59f SR |
3683 | { |
3684 | struct ftrace_iterator *iter; | |
f45948e8 | 3685 | struct ftrace_hash *hash; |
673feb9d SRV |
3686 | struct list_head *mod_head; |
3687 | struct trace_array *tr = ops->private; | |
9ef16693 | 3688 | int ret = -ENOMEM; |
5072c59f | 3689 | |
f04f24fb MH |
3690 | ftrace_ops_init(ops); |
3691 | ||
4eebcc81 SR |
3692 | if (unlikely(ftrace_disabled)) |
3693 | return -ENODEV; | |
3694 | ||
8530dec6 | 3695 | if (tracing_check_open_get_tr(tr)) |
9ef16693 SRV |
3696 | return -ENODEV; |
3697 | ||
5072c59f SR |
3698 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
3699 | if (!iter) | |
9ef16693 | 3700 | goto out; |
5072c59f | 3701 | |
9ef16693 SRV |
3702 | if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) |
3703 | goto out; | |
689fd8b6 | 3704 | |
3f2367ba MH |
3705 | iter->ops = ops; |
3706 | iter->flags = flag; | |
5985ea8b | 3707 | iter->tr = tr; |
3f2367ba | 3708 | |
33b7f99c | 3709 | mutex_lock(&ops->func_hash->regex_lock); |
3f2367ba | 3710 | |
673feb9d | 3711 | if (flag & FTRACE_ITER_NOTRACE) { |
33b7f99c | 3712 | hash = ops->func_hash->notrace_hash; |
5985ea8b | 3713 | mod_head = tr ? &tr->mod_notrace : NULL; |
673feb9d | 3714 | } else { |
33b7f99c | 3715 | hash = ops->func_hash->filter_hash; |
5985ea8b | 3716 | mod_head = tr ? &tr->mod_trace : NULL; |
673feb9d | 3717 | } |
f45948e8 | 3718 | |
5985ea8b SRV |
3719 | iter->mod_list = mod_head; |
3720 | ||
33dc9b12 | 3721 | if (file->f_mode & FMODE_WRITE) { |
ef2fbe16 NK |
3722 | const int size_bits = FTRACE_HASH_DEFAULT_BITS; |
3723 | ||
673feb9d | 3724 | if (file->f_flags & O_TRUNC) { |
ef2fbe16 | 3725 | iter->hash = alloc_ftrace_hash(size_bits); |
673feb9d SRV |
3726 | clear_ftrace_mod_list(mod_head); |
3727 | } else { | |
ef2fbe16 | 3728 | iter->hash = alloc_and_copy_ftrace_hash(size_bits, hash); |
673feb9d | 3729 | } |
ef2fbe16 | 3730 | |
33dc9b12 SR |
3731 | if (!iter->hash) { |
3732 | trace_parser_put(&iter->parser); | |
3f2367ba | 3733 | goto out_unlock; |
33dc9b12 | 3734 | } |
c20489da SRV |
3735 | } else |
3736 | iter->hash = hash; | |
1cf41dd7 | 3737 | |
9ef16693 SRV |
3738 | ret = 0; |
3739 | ||
5072c59f SR |
3740 | if (file->f_mode & FMODE_READ) { |
3741 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
3742 | |
3743 | ret = seq_open(file, &show_ftrace_seq_ops); | |
3744 | if (!ret) { | |
3745 | struct seq_file *m = file->private_data; | |
3746 | m->private = iter; | |
79fe249c | 3747 | } else { |
33dc9b12 SR |
3748 | /* Failed */ |
3749 | free_ftrace_hash(iter->hash); | |
79fe249c | 3750 | trace_parser_put(&iter->parser); |
79fe249c | 3751 | } |
5072c59f SR |
3752 | } else |
3753 | file->private_data = iter; | |
3f2367ba MH |
3754 | |
3755 | out_unlock: | |
33b7f99c | 3756 | mutex_unlock(&ops->func_hash->regex_lock); |
5072c59f | 3757 | |
9ef16693 SRV |
3758 | out: |
3759 | if (ret) { | |
3760 | kfree(iter); | |
3761 | if (tr) | |
3762 | trace_array_put(tr); | |
3763 | } | |
3764 | ||
5072c59f SR |
3765 | return ret; |
3766 | } | |
3767 | ||
41c52c0d SR |
3768 | static int |
3769 | ftrace_filter_open(struct inode *inode, struct file *file) | |
3770 | { | |
e3b3e2e8 SRRH |
3771 | struct ftrace_ops *ops = inode->i_private; |
3772 | ||
17911ff3 | 3773 | /* Checks for tracefs lockdown */ |
e3b3e2e8 | 3774 | return ftrace_regex_open(ops, |
eee8ded1 | 3775 | FTRACE_ITER_FILTER | FTRACE_ITER_DO_PROBES, |
69a3083c | 3776 | inode, file); |
41c52c0d SR |
3777 | } |
3778 | ||
3779 | static int | |
3780 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
3781 | { | |
e3b3e2e8 SRRH |
3782 | struct ftrace_ops *ops = inode->i_private; |
3783 | ||
17911ff3 | 3784 | /* Checks for tracefs lockdown */ |
e3b3e2e8 | 3785 | return ftrace_regex_open(ops, FTRACE_ITER_NOTRACE, |
1cf41dd7 | 3786 | inode, file); |
41c52c0d SR |
3787 | } |
3788 | ||
3ba00929 DS |
3789 | /* Type for quick search ftrace basic regexes (globs) from filter_parse_regex */ |
3790 | struct ftrace_glob { | |
3791 | char *search; | |
3792 | unsigned len; | |
3793 | int type; | |
3794 | }; | |
3795 | ||
7132e2d6 TJB |
3796 | /* |
3797 | * If symbols in an architecture don't correspond exactly to the user-visible | |
3798 | * name of what they represent, it is possible to define this function to | |
3799 | * perform the necessary adjustments. | |
3800 | */ | |
3801 | char * __weak arch_ftrace_match_adjust(char *str, const char *search) | |
3802 | { | |
3803 | return str; | |
3804 | } | |
3805 | ||
3ba00929 | 3806 | static int ftrace_match(char *str, struct ftrace_glob *g) |
9f4801e3 | 3807 | { |
9f4801e3 | 3808 | int matched = 0; |
751e9983 | 3809 | int slen; |
9f4801e3 | 3810 | |
7132e2d6 TJB |
3811 | str = arch_ftrace_match_adjust(str, g->search); |
3812 | ||
3ba00929 | 3813 | switch (g->type) { |
9f4801e3 | 3814 | case MATCH_FULL: |
3ba00929 | 3815 | if (strcmp(str, g->search) == 0) |
9f4801e3 SR |
3816 | matched = 1; |
3817 | break; | |
3818 | case MATCH_FRONT_ONLY: | |
3ba00929 | 3819 | if (strncmp(str, g->search, g->len) == 0) |
9f4801e3 SR |
3820 | matched = 1; |
3821 | break; | |
3822 | case MATCH_MIDDLE_ONLY: | |
3ba00929 | 3823 | if (strstr(str, g->search)) |
9f4801e3 SR |
3824 | matched = 1; |
3825 | break; | |
3826 | case MATCH_END_ONLY: | |
751e9983 | 3827 | slen = strlen(str); |
3ba00929 DS |
3828 | if (slen >= g->len && |
3829 | memcmp(str + slen - g->len, g->search, g->len) == 0) | |
9f4801e3 SR |
3830 | matched = 1; |
3831 | break; | |
60f1d5e3 MH |
3832 | case MATCH_GLOB: |
3833 | if (glob_match(g->search, str)) | |
3834 | matched = 1; | |
3835 | break; | |
9f4801e3 SR |
3836 | } |
3837 | ||
3838 | return matched; | |
3839 | } | |
3840 | ||
b448c4e3 | 3841 | static int |
f0a3b154 | 3842 | enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int clear_filter) |
996e87be | 3843 | { |
b448c4e3 | 3844 | struct ftrace_func_entry *entry; |
b448c4e3 SR |
3845 | int ret = 0; |
3846 | ||
1cf41dd7 | 3847 | entry = ftrace_lookup_ip(hash, rec->ip); |
f0a3b154 | 3848 | if (clear_filter) { |
1cf41dd7 SR |
3849 | /* Do nothing if it doesn't exist */ |
3850 | if (!entry) | |
3851 | return 0; | |
b448c4e3 | 3852 | |
33dc9b12 | 3853 | free_hash_entry(hash, entry); |
1cf41dd7 SR |
3854 | } else { |
3855 | /* Do nothing if it exists */ | |
3856 | if (entry) | |
3857 | return 0; | |
b448c4e3 | 3858 | |
1cf41dd7 | 3859 | ret = add_hash_entry(hash, rec->ip); |
b448c4e3 SR |
3860 | } |
3861 | return ret; | |
996e87be SR |
3862 | } |
3863 | ||
f79b3f33 SRV |
3864 | static int |
3865 | add_rec_by_index(struct ftrace_hash *hash, struct ftrace_glob *func_g, | |
3866 | int clear_filter) | |
3867 | { | |
3868 | long index = simple_strtoul(func_g->search, NULL, 0); | |
3869 | struct ftrace_page *pg; | |
3870 | struct dyn_ftrace *rec; | |
3871 | ||
3872 | /* The index starts at 1 */ | |
3873 | if (--index < 0) | |
3874 | return 0; | |
3875 | ||
3876 | do_for_each_ftrace_rec(pg, rec) { | |
3877 | if (pg->index <= index) { | |
3878 | index -= pg->index; | |
3879 | /* this is a double loop, break goes to the next page */ | |
3880 | break; | |
3881 | } | |
3882 | rec = &pg->records[index]; | |
3883 | enter_record(hash, rec, clear_filter); | |
3884 | return 1; | |
3885 | } while_for_each_ftrace_rec(); | |
3886 | return 0; | |
3887 | } | |
3888 | ||
64e7c440 | 3889 | static int |
0b507e1e DS |
3890 | ftrace_match_record(struct dyn_ftrace *rec, struct ftrace_glob *func_g, |
3891 | struct ftrace_glob *mod_g, int exclude_mod) | |
64e7c440 SR |
3892 | { |
3893 | char str[KSYM_SYMBOL_LEN]; | |
b9df92d2 SR |
3894 | char *modname; |
3895 | ||
3896 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); | |
3897 | ||
0b507e1e DS |
3898 | if (mod_g) { |
3899 | int mod_matches = (modname) ? ftrace_match(modname, mod_g) : 0; | |
3900 | ||
3901 | /* blank module name to match all modules */ | |
3902 | if (!mod_g->len) { | |
3903 | /* blank module globbing: modname xor exclude_mod */ | |
77c0edde | 3904 | if (!exclude_mod != !modname) |
0b507e1e DS |
3905 | goto func_match; |
3906 | return 0; | |
3907 | } | |
3908 | ||
77c0edde SRV |
3909 | /* |
3910 | * exclude_mod is set to trace everything but the given | |
3911 | * module. If it is set and the module matches, then | |
3912 | * return 0. If it is not set, and the module doesn't match | |
3913 | * also return 0. Otherwise, check the function to see if | |
3914 | * that matches. | |
3915 | */ | |
3916 | if (!mod_matches == !exclude_mod) | |
b9df92d2 | 3917 | return 0; |
0b507e1e | 3918 | func_match: |
b9df92d2 | 3919 | /* blank search means to match all funcs in the mod */ |
3ba00929 | 3920 | if (!func_g->len) |
b9df92d2 SR |
3921 | return 1; |
3922 | } | |
64e7c440 | 3923 | |
3ba00929 | 3924 | return ftrace_match(str, func_g); |
64e7c440 SR |
3925 | } |
3926 | ||
1cf41dd7 | 3927 | static int |
3ba00929 | 3928 | match_records(struct ftrace_hash *hash, char *func, int len, char *mod) |
9f4801e3 | 3929 | { |
9f4801e3 SR |
3930 | struct ftrace_page *pg; |
3931 | struct dyn_ftrace *rec; | |
3ba00929 | 3932 | struct ftrace_glob func_g = { .type = MATCH_FULL }; |
0b507e1e DS |
3933 | struct ftrace_glob mod_g = { .type = MATCH_FULL }; |
3934 | struct ftrace_glob *mod_match = (mod) ? &mod_g : NULL; | |
3935 | int exclude_mod = 0; | |
311d16da | 3936 | int found = 0; |
b448c4e3 | 3937 | int ret; |
2e028c4f | 3938 | int clear_filter = 0; |
9f4801e3 | 3939 | |
0b507e1e | 3940 | if (func) { |
3ba00929 DS |
3941 | func_g.type = filter_parse_regex(func, len, &func_g.search, |
3942 | &clear_filter); | |
3943 | func_g.len = strlen(func_g.search); | |
b9df92d2 | 3944 | } |
9f4801e3 | 3945 | |
0b507e1e DS |
3946 | if (mod) { |
3947 | mod_g.type = filter_parse_regex(mod, strlen(mod), | |
3948 | &mod_g.search, &exclude_mod); | |
3949 | mod_g.len = strlen(mod_g.search); | |
b9df92d2 | 3950 | } |
9f4801e3 | 3951 | |
52baf119 | 3952 | mutex_lock(&ftrace_lock); |
265c831c | 3953 | |
b9df92d2 SR |
3954 | if (unlikely(ftrace_disabled)) |
3955 | goto out_unlock; | |
9f4801e3 | 3956 | |
f79b3f33 SRV |
3957 | if (func_g.type == MATCH_INDEX) { |
3958 | found = add_rec_by_index(hash, &func_g, clear_filter); | |
3959 | goto out_unlock; | |
3960 | } | |
3961 | ||
265c831c | 3962 | do_for_each_ftrace_rec(pg, rec) { |
546fece4 SRRH |
3963 | |
3964 | if (rec->flags & FTRACE_FL_DISABLED) | |
3965 | continue; | |
3966 | ||
0b507e1e | 3967 | if (ftrace_match_record(rec, &func_g, mod_match, exclude_mod)) { |
f0a3b154 | 3968 | ret = enter_record(hash, rec, clear_filter); |
b448c4e3 SR |
3969 | if (ret < 0) { |
3970 | found = ret; | |
3971 | goto out_unlock; | |
3972 | } | |
311d16da | 3973 | found = 1; |
265c831c SR |
3974 | } |
3975 | } while_for_each_ftrace_rec(); | |
b9df92d2 | 3976 | out_unlock: |
52baf119 | 3977 | mutex_unlock(&ftrace_lock); |
311d16da LZ |
3978 | |
3979 | return found; | |
5072c59f SR |
3980 | } |
3981 | ||
64e7c440 | 3982 | static int |
1cf41dd7 | 3983 | ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) |
64e7c440 | 3984 | { |
f0a3b154 | 3985 | return match_records(hash, buff, len, NULL); |
64e7c440 SR |
3986 | } |
3987 | ||
e16b35dd SRV |
3988 | static void ftrace_ops_update_code(struct ftrace_ops *ops, |
3989 | struct ftrace_ops_hash *old_hash) | |
3990 | { | |
3991 | struct ftrace_ops *op; | |
3992 | ||
3993 | if (!ftrace_enabled) | |
3994 | return; | |
3995 | ||
3996 | if (ops->flags & FTRACE_OPS_FL_ENABLED) { | |
3997 | ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS, old_hash); | |
3998 | return; | |
3999 | } | |
4000 | ||
4001 | /* | |
4002 | * If this is the shared global_ops filter, then we need to | |
4003 | * check if there is another ops that shares it, is enabled. | |
4004 | * If so, we still need to run the modify code. | |
4005 | */ | |
4006 | if (ops->func_hash != &global_ops.local_hash) | |
4007 | return; | |
4008 | ||
4009 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
4010 | if (op->func_hash == &global_ops.local_hash && | |
4011 | op->flags & FTRACE_OPS_FL_ENABLED) { | |
4012 | ftrace_run_modify_code(op, FTRACE_UPDATE_CALLS, old_hash); | |
4013 | /* Only need to do this once */ | |
4014 | return; | |
4015 | } | |
4016 | } while_for_each_ftrace_op(op); | |
4017 | } | |
4018 | ||
4019 | static int ftrace_hash_move_and_update_ops(struct ftrace_ops *ops, | |
4020 | struct ftrace_hash **orig_hash, | |
4021 | struct ftrace_hash *hash, | |
4022 | int enable) | |
4023 | { | |
4024 | struct ftrace_ops_hash old_hash_ops; | |
4025 | struct ftrace_hash *old_hash; | |
4026 | int ret; | |
4027 | ||
4028 | old_hash = *orig_hash; | |
4029 | old_hash_ops.filter_hash = ops->func_hash->filter_hash; | |
4030 | old_hash_ops.notrace_hash = ops->func_hash->notrace_hash; | |
4031 | ret = ftrace_hash_move(ops, enable, orig_hash, hash); | |
4032 | if (!ret) { | |
4033 | ftrace_ops_update_code(ops, &old_hash_ops); | |
4034 | free_ftrace_hash_rcu(old_hash); | |
4035 | } | |
4036 | return ret; | |
4037 | } | |
64e7c440 | 4038 | |
673feb9d SRV |
4039 | static bool module_exists(const char *module) |
4040 | { | |
4041 | /* All modules have the symbol __this_module */ | |
0f5e5a3a | 4042 | static const char this_mod[] = "__this_module"; |
419e9fe5 | 4043 | char modname[MAX_PARAM_PREFIX_LEN + sizeof(this_mod) + 2]; |
673feb9d SRV |
4044 | unsigned long val; |
4045 | int n; | |
4046 | ||
419e9fe5 | 4047 | n = snprintf(modname, sizeof(modname), "%s:%s", module, this_mod); |
673feb9d | 4048 | |
419e9fe5 | 4049 | if (n > sizeof(modname) - 1) |
673feb9d SRV |
4050 | return false; |
4051 | ||
4052 | val = module_kallsyms_lookup_name(modname); | |
4053 | return val != 0; | |
4054 | } | |
4055 | ||
4056 | static int cache_mod(struct trace_array *tr, | |
4057 | const char *func, char *module, int enable) | |
4058 | { | |
4059 | struct ftrace_mod_load *ftrace_mod, *n; | |
4060 | struct list_head *head = enable ? &tr->mod_trace : &tr->mod_notrace; | |
4061 | int ret; | |
4062 | ||
4063 | mutex_lock(&ftrace_lock); | |
4064 | ||
4065 | /* We do not cache inverse filters */ | |
4066 | if (func[0] == '!') { | |
4067 | func++; | |
4068 | ret = -EINVAL; | |
4069 | ||
4070 | /* Look to remove this hash */ | |
4071 | list_for_each_entry_safe(ftrace_mod, n, head, list) { | |
4072 | if (strcmp(ftrace_mod->module, module) != 0) | |
4073 | continue; | |
4074 | ||
4075 | /* no func matches all */ | |
44925dff | 4076 | if (strcmp(func, "*") == 0 || |
673feb9d SRV |
4077 | (ftrace_mod->func && |
4078 | strcmp(ftrace_mod->func, func) == 0)) { | |
4079 | ret = 0; | |
4080 | free_ftrace_mod(ftrace_mod); | |
4081 | continue; | |
4082 | } | |
4083 | } | |
4084 | goto out; | |
4085 | } | |
4086 | ||
4087 | ret = -EINVAL; | |
4088 | /* We only care about modules that have not been loaded yet */ | |
4089 | if (module_exists(module)) | |
4090 | goto out; | |
4091 | ||
4092 | /* Save this string off, and execute it when the module is loaded */ | |
4093 | ret = ftrace_add_mod(tr, func, module, enable); | |
4094 | out: | |
4095 | mutex_unlock(&ftrace_lock); | |
4096 | ||
4097 | return ret; | |
4098 | } | |
4099 | ||
d7fbf8df SRV |
4100 | static int |
4101 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, | |
4102 | int reset, int enable); | |
4103 | ||
69449bbd | 4104 | #ifdef CONFIG_MODULES |
d7fbf8df SRV |
4105 | static void process_mod_list(struct list_head *head, struct ftrace_ops *ops, |
4106 | char *mod, bool enable) | |
4107 | { | |
4108 | struct ftrace_mod_load *ftrace_mod, *n; | |
4109 | struct ftrace_hash **orig_hash, *new_hash; | |
4110 | LIST_HEAD(process_mods); | |
4111 | char *func; | |
4112 | int ret; | |
4113 | ||
4114 | mutex_lock(&ops->func_hash->regex_lock); | |
4115 | ||
4116 | if (enable) | |
4117 | orig_hash = &ops->func_hash->filter_hash; | |
4118 | else | |
4119 | orig_hash = &ops->func_hash->notrace_hash; | |
4120 | ||
4121 | new_hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, | |
4122 | *orig_hash); | |
4123 | if (!new_hash) | |
3b58a3c7 | 4124 | goto out; /* warn? */ |
d7fbf8df SRV |
4125 | |
4126 | mutex_lock(&ftrace_lock); | |
4127 | ||
4128 | list_for_each_entry_safe(ftrace_mod, n, head, list) { | |
4129 | ||
4130 | if (strcmp(ftrace_mod->module, mod) != 0) | |
4131 | continue; | |
4132 | ||
4133 | if (ftrace_mod->func) | |
4134 | func = kstrdup(ftrace_mod->func, GFP_KERNEL); | |
4135 | else | |
4136 | func = kstrdup("*", GFP_KERNEL); | |
4137 | ||
4138 | if (!func) /* warn? */ | |
4139 | continue; | |
4140 | ||
4141 | list_del(&ftrace_mod->list); | |
4142 | list_add(&ftrace_mod->list, &process_mods); | |
4143 | ||
4144 | /* Use the newly allocated func, as it may be "*" */ | |
4145 | kfree(ftrace_mod->func); | |
4146 | ftrace_mod->func = func; | |
4147 | } | |
4148 | ||
4149 | mutex_unlock(&ftrace_lock); | |
4150 | ||
4151 | list_for_each_entry_safe(ftrace_mod, n, &process_mods, list) { | |
4152 | ||
4153 | func = ftrace_mod->func; | |
4154 | ||
4155 | /* Grabs ftrace_lock, which is why we have this extra step */ | |
4156 | match_records(new_hash, func, strlen(func), mod); | |
4157 | free_ftrace_mod(ftrace_mod); | |
4158 | } | |
4159 | ||
8c08f0d5 SRV |
4160 | if (enable && list_empty(head)) |
4161 | new_hash->flags &= ~FTRACE_HASH_FL_MOD; | |
4162 | ||
d7fbf8df SRV |
4163 | mutex_lock(&ftrace_lock); |
4164 | ||
4165 | ret = ftrace_hash_move_and_update_ops(ops, orig_hash, | |
4166 | new_hash, enable); | |
4167 | mutex_unlock(&ftrace_lock); | |
4168 | ||
3b58a3c7 | 4169 | out: |
d7fbf8df SRV |
4170 | mutex_unlock(&ops->func_hash->regex_lock); |
4171 | ||
4172 | free_ftrace_hash(new_hash); | |
4173 | } | |
4174 | ||
4175 | static void process_cached_mods(const char *mod_name) | |
4176 | { | |
4177 | struct trace_array *tr; | |
4178 | char *mod; | |
4179 | ||
4180 | mod = kstrdup(mod_name, GFP_KERNEL); | |
4181 | if (!mod) | |
4182 | return; | |
4183 | ||
4184 | mutex_lock(&trace_types_lock); | |
4185 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
4186 | if (!list_empty(&tr->mod_trace)) | |
4187 | process_mod_list(&tr->mod_trace, tr->ops, mod, true); | |
4188 | if (!list_empty(&tr->mod_notrace)) | |
4189 | process_mod_list(&tr->mod_notrace, tr->ops, mod, false); | |
4190 | } | |
4191 | mutex_unlock(&trace_types_lock); | |
4192 | ||
4193 | kfree(mod); | |
4194 | } | |
69449bbd | 4195 | #endif |
d7fbf8df | 4196 | |
f6180773 SR |
4197 | /* |
4198 | * We register the module command as a template to show others how | |
4199 | * to register the a command as well. | |
4200 | */ | |
4201 | ||
4202 | static int | |
04ec7bb6 | 4203 | ftrace_mod_callback(struct trace_array *tr, struct ftrace_hash *hash, |
673feb9d | 4204 | char *func_orig, char *cmd, char *module, int enable) |
f6180773 | 4205 | { |
673feb9d | 4206 | char *func; |
5e3949f0 | 4207 | int ret; |
f6180773 | 4208 | |
673feb9d SRV |
4209 | /* match_records() modifies func, and we need the original */ |
4210 | func = kstrdup(func_orig, GFP_KERNEL); | |
4211 | if (!func) | |
4212 | return -ENOMEM; | |
4213 | ||
f6180773 SR |
4214 | /* |
4215 | * cmd == 'mod' because we only registered this func | |
4216 | * for the 'mod' ftrace_func_command. | |
4217 | * But if you register one func with multiple commands, | |
4218 | * you can tell which command was used by the cmd | |
4219 | * parameter. | |
4220 | */ | |
f0a3b154 | 4221 | ret = match_records(hash, func, strlen(func), module); |
673feb9d SRV |
4222 | kfree(func); |
4223 | ||
b448c4e3 | 4224 | if (!ret) |
673feb9d | 4225 | return cache_mod(tr, func_orig, module, enable); |
b448c4e3 SR |
4226 | if (ret < 0) |
4227 | return ret; | |
b448c4e3 | 4228 | return 0; |
f6180773 SR |
4229 | } |
4230 | ||
4231 | static struct ftrace_func_command ftrace_mod_cmd = { | |
4232 | .name = "mod", | |
4233 | .func = ftrace_mod_callback, | |
4234 | }; | |
4235 | ||
4236 | static int __init ftrace_mod_cmd_init(void) | |
4237 | { | |
4238 | return register_ftrace_command(&ftrace_mod_cmd); | |
4239 | } | |
6f415672 | 4240 | core_initcall(ftrace_mod_cmd_init); |
f6180773 | 4241 | |
2f5f6ad9 | 4242 | static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 4243 | struct ftrace_ops *op, struct pt_regs *pt_regs) |
59df055f | 4244 | { |
eee8ded1 | 4245 | struct ftrace_probe_ops *probe_ops; |
7b60f3d8 | 4246 | struct ftrace_func_probe *probe; |
59df055f | 4247 | |
7b60f3d8 SRV |
4248 | probe = container_of(op, struct ftrace_func_probe, ops); |
4249 | probe_ops = probe->probe_ops; | |
59df055f SR |
4250 | |
4251 | /* | |
4252 | * Disable preemption for these calls to prevent a RCU grace | |
4253 | * period. This syncs the hash iteration and freeing of items | |
4254 | * on the hash. rcu_read_lock is too dangerous here. | |
4255 | */ | |
5168ae50 | 4256 | preempt_disable_notrace(); |
6e444319 | 4257 | probe_ops->func(ip, parent_ip, probe->tr, probe_ops, probe->data); |
5168ae50 | 4258 | preempt_enable_notrace(); |
59df055f SR |
4259 | } |
4260 | ||
41794f19 SRV |
4261 | struct ftrace_func_map { |
4262 | struct ftrace_func_entry entry; | |
4263 | void *data; | |
59df055f SR |
4264 | }; |
4265 | ||
41794f19 SRV |
4266 | struct ftrace_func_mapper { |
4267 | struct ftrace_hash hash; | |
4268 | }; | |
59df055f | 4269 | |
41794f19 SRV |
4270 | /** |
4271 | * allocate_ftrace_func_mapper - allocate a new ftrace_func_mapper | |
4272 | * | |
4273 | * Returns a ftrace_func_mapper descriptor that can be used to map ips to data. | |
4274 | */ | |
4275 | struct ftrace_func_mapper *allocate_ftrace_func_mapper(void) | |
59df055f | 4276 | { |
41794f19 | 4277 | struct ftrace_hash *hash; |
59df055f | 4278 | |
41794f19 SRV |
4279 | /* |
4280 | * The mapper is simply a ftrace_hash, but since the entries | |
4281 | * in the hash are not ftrace_func_entry type, we define it | |
4282 | * as a separate structure. | |
4283 | */ | |
4284 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); | |
4285 | return (struct ftrace_func_mapper *)hash; | |
4286 | } | |
59df055f | 4287 | |
41794f19 SRV |
4288 | /** |
4289 | * ftrace_func_mapper_find_ip - Find some data mapped to an ip | |
4290 | * @mapper: The mapper that has the ip maps | |
4291 | * @ip: the instruction pointer to find the data for | |
4292 | * | |
4293 | * Returns the data mapped to @ip if found otherwise NULL. The return | |
4294 | * is actually the address of the mapper data pointer. The address is | |
4295 | * returned for use cases where the data is no bigger than a long, and | |
4296 | * the user can use the data pointer as its data instead of having to | |
4297 | * allocate more memory for the reference. | |
4298 | */ | |
4299 | void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper, | |
4300 | unsigned long ip) | |
4301 | { | |
4302 | struct ftrace_func_entry *entry; | |
4303 | struct ftrace_func_map *map; | |
59df055f | 4304 | |
41794f19 SRV |
4305 | entry = ftrace_lookup_ip(&mapper->hash, ip); |
4306 | if (!entry) | |
4307 | return NULL; | |
b848914c | 4308 | |
41794f19 SRV |
4309 | map = (struct ftrace_func_map *)entry; |
4310 | return &map->data; | |
59df055f SR |
4311 | } |
4312 | ||
41794f19 SRV |
4313 | /** |
4314 | * ftrace_func_mapper_add_ip - Map some data to an ip | |
4315 | * @mapper: The mapper that has the ip maps | |
4316 | * @ip: The instruction pointer address to map @data to | |
4317 | * @data: The data to map to @ip | |
4318 | * | |
4319 | * Returns 0 on succes otherwise an error. | |
4320 | */ | |
4321 | int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper, | |
4322 | unsigned long ip, void *data) | |
59df055f | 4323 | { |
41794f19 SRV |
4324 | struct ftrace_func_entry *entry; |
4325 | struct ftrace_func_map *map; | |
59df055f | 4326 | |
41794f19 SRV |
4327 | entry = ftrace_lookup_ip(&mapper->hash, ip); |
4328 | if (entry) | |
4329 | return -EBUSY; | |
59df055f | 4330 | |
41794f19 SRV |
4331 | map = kmalloc(sizeof(*map), GFP_KERNEL); |
4332 | if (!map) | |
4333 | return -ENOMEM; | |
59df055f | 4334 | |
41794f19 SRV |
4335 | map->entry.ip = ip; |
4336 | map->data = data; | |
b848914c | 4337 | |
41794f19 | 4338 | __add_hash_entry(&mapper->hash, &map->entry); |
59df055f | 4339 | |
41794f19 SRV |
4340 | return 0; |
4341 | } | |
59df055f | 4342 | |
41794f19 SRV |
4343 | /** |
4344 | * ftrace_func_mapper_remove_ip - Remove an ip from the mapping | |
4345 | * @mapper: The mapper that has the ip maps | |
4346 | * @ip: The instruction pointer address to remove the data from | |
4347 | * | |
4348 | * Returns the data if it is found, otherwise NULL. | |
4349 | * Note, if the data pointer is used as the data itself, (see | |
4350 | * ftrace_func_mapper_find_ip(), then the return value may be meaningless, | |
4351 | * if the data pointer was set to zero. | |
4352 | */ | |
4353 | void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper, | |
4354 | unsigned long ip) | |
59df055f | 4355 | { |
41794f19 SRV |
4356 | struct ftrace_func_entry *entry; |
4357 | struct ftrace_func_map *map; | |
4358 | void *data; | |
4359 | ||
4360 | entry = ftrace_lookup_ip(&mapper->hash, ip); | |
4361 | if (!entry) | |
4362 | return NULL; | |
4363 | ||
4364 | map = (struct ftrace_func_map *)entry; | |
4365 | data = map->data; | |
4366 | ||
4367 | remove_hash_entry(&mapper->hash, entry); | |
59df055f | 4368 | kfree(entry); |
41794f19 SRV |
4369 | |
4370 | return data; | |
4371 | } | |
4372 | ||
4373 | /** | |
4374 | * free_ftrace_func_mapper - free a mapping of ips and data | |
4375 | * @mapper: The mapper that has the ip maps | |
4376 | * @free_func: A function to be called on each data item. | |
4377 | * | |
4378 | * This is used to free the function mapper. The @free_func is optional | |
4379 | * and can be used if the data needs to be freed as well. | |
4380 | */ | |
4381 | void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper, | |
4382 | ftrace_mapper_func free_func) | |
4383 | { | |
4384 | struct ftrace_func_entry *entry; | |
4385 | struct ftrace_func_map *map; | |
4386 | struct hlist_head *hhd; | |
04e03d9a WL |
4387 | int size, i; |
4388 | ||
4389 | if (!mapper) | |
4390 | return; | |
41794f19 SRV |
4391 | |
4392 | if (free_func && mapper->hash.count) { | |
04e03d9a | 4393 | size = 1 << mapper->hash.size_bits; |
41794f19 SRV |
4394 | for (i = 0; i < size; i++) { |
4395 | hhd = &mapper->hash.buckets[i]; | |
4396 | hlist_for_each_entry(entry, hhd, hlist) { | |
4397 | map = (struct ftrace_func_map *)entry; | |
4398 | free_func(map); | |
4399 | } | |
4400 | } | |
4401 | } | |
4402 | free_ftrace_hash(&mapper->hash); | |
4403 | } | |
4404 | ||
7b60f3d8 SRV |
4405 | static void release_probe(struct ftrace_func_probe *probe) |
4406 | { | |
4407 | struct ftrace_probe_ops *probe_ops; | |
4408 | ||
4409 | mutex_lock(&ftrace_lock); | |
4410 | ||
4411 | WARN_ON(probe->ref <= 0); | |
4412 | ||
4413 | /* Subtract the ref that was used to protect this instance */ | |
4414 | probe->ref--; | |
4415 | ||
4416 | if (!probe->ref) { | |
4417 | probe_ops = probe->probe_ops; | |
6e444319 SRV |
4418 | /* |
4419 | * Sending zero as ip tells probe_ops to free | |
4420 | * the probe->data itself | |
4421 | */ | |
4422 | if (probe_ops->free) | |
4423 | probe_ops->free(probe_ops, probe->tr, 0, probe->data); | |
7b60f3d8 SRV |
4424 | list_del(&probe->list); |
4425 | kfree(probe); | |
4426 | } | |
4427 | mutex_unlock(&ftrace_lock); | |
4428 | } | |
4429 | ||
4430 | static void acquire_probe_locked(struct ftrace_func_probe *probe) | |
4431 | { | |
4432 | /* | |
4433 | * Add one ref to keep it from being freed when releasing the | |
4434 | * ftrace_lock mutex. | |
4435 | */ | |
4436 | probe->ref++; | |
59df055f SR |
4437 | } |
4438 | ||
59df055f | 4439 | int |
04ec7bb6 | 4440 | register_ftrace_function_probe(char *glob, struct trace_array *tr, |
7b60f3d8 SRV |
4441 | struct ftrace_probe_ops *probe_ops, |
4442 | void *data) | |
59df055f | 4443 | { |
1ec3a81a | 4444 | struct ftrace_func_entry *entry; |
7b60f3d8 | 4445 | struct ftrace_func_probe *probe; |
1ec3a81a SRV |
4446 | struct ftrace_hash **orig_hash; |
4447 | struct ftrace_hash *old_hash; | |
e1df4cb6 | 4448 | struct ftrace_hash *hash; |
59df055f | 4449 | int count = 0; |
1ec3a81a | 4450 | int size; |
e1df4cb6 | 4451 | int ret; |
1ec3a81a | 4452 | int i; |
59df055f | 4453 | |
04ec7bb6 | 4454 | if (WARN_ON(!tr)) |
59df055f SR |
4455 | return -EINVAL; |
4456 | ||
1ec3a81a SRV |
4457 | /* We do not support '!' for function probes */ |
4458 | if (WARN_ON(glob[0] == '!')) | |
59df055f | 4459 | return -EINVAL; |
59df055f | 4460 | |
7485058e | 4461 | |
7b60f3d8 SRV |
4462 | mutex_lock(&ftrace_lock); |
4463 | /* Check if the probe_ops is already registered */ | |
4464 | list_for_each_entry(probe, &tr->func_probes, list) { | |
4465 | if (probe->probe_ops == probe_ops) | |
4466 | break; | |
e1df4cb6 | 4467 | } |
7b60f3d8 SRV |
4468 | if (&probe->list == &tr->func_probes) { |
4469 | probe = kzalloc(sizeof(*probe), GFP_KERNEL); | |
4470 | if (!probe) { | |
4471 | mutex_unlock(&ftrace_lock); | |
4472 | return -ENOMEM; | |
4473 | } | |
4474 | probe->probe_ops = probe_ops; | |
4475 | probe->ops.func = function_trace_probe_call; | |
4476 | probe->tr = tr; | |
4477 | ftrace_ops_init(&probe->ops); | |
4478 | list_add(&probe->list, &tr->func_probes); | |
e1df4cb6 | 4479 | } |
59df055f | 4480 | |
7b60f3d8 | 4481 | acquire_probe_locked(probe); |
5ae0bf59 | 4482 | |
7b60f3d8 | 4483 | mutex_unlock(&ftrace_lock); |
59df055f | 4484 | |
372e0d01 SRV |
4485 | /* |
4486 | * Note, there's a small window here that the func_hash->filter_hash | |
4487 | * may be NULL or empty. Need to be carefule when reading the loop. | |
4488 | */ | |
7b60f3d8 | 4489 | mutex_lock(&probe->ops.func_hash->regex_lock); |
546fece4 | 4490 | |
7b60f3d8 | 4491 | orig_hash = &probe->ops.func_hash->filter_hash; |
1ec3a81a SRV |
4492 | old_hash = *orig_hash; |
4493 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash); | |
59df055f | 4494 | |
5b0022dd NR |
4495 | if (!hash) { |
4496 | ret = -ENOMEM; | |
4497 | goto out; | |
4498 | } | |
4499 | ||
1ec3a81a | 4500 | ret = ftrace_match_records(hash, glob, strlen(glob)); |
59df055f | 4501 | |
1ec3a81a SRV |
4502 | /* Nothing found? */ |
4503 | if (!ret) | |
4504 | ret = -EINVAL; | |
59df055f | 4505 | |
1ec3a81a SRV |
4506 | if (ret < 0) |
4507 | goto out; | |
59df055f | 4508 | |
1ec3a81a SRV |
4509 | size = 1 << hash->size_bits; |
4510 | for (i = 0; i < size; i++) { | |
4511 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { | |
4512 | if (ftrace_lookup_ip(old_hash, entry->ip)) | |
59df055f | 4513 | continue; |
1ec3a81a SRV |
4514 | /* |
4515 | * The caller might want to do something special | |
4516 | * for each function we find. We call the callback | |
4517 | * to give the caller an opportunity to do so. | |
4518 | */ | |
7b60f3d8 SRV |
4519 | if (probe_ops->init) { |
4520 | ret = probe_ops->init(probe_ops, tr, | |
6e444319 SRV |
4521 | entry->ip, data, |
4522 | &probe->data); | |
4523 | if (ret < 0) { | |
4524 | if (probe_ops->free && count) | |
4525 | probe_ops->free(probe_ops, tr, | |
4526 | 0, probe->data); | |
4527 | probe->data = NULL; | |
eee8ded1 | 4528 | goto out; |
6e444319 | 4529 | } |
59df055f | 4530 | } |
1ec3a81a | 4531 | count++; |
59df055f | 4532 | } |
1ec3a81a | 4533 | } |
59df055f | 4534 | |
1ec3a81a | 4535 | mutex_lock(&ftrace_lock); |
59df055f | 4536 | |
7b60f3d8 SRV |
4537 | if (!count) { |
4538 | /* Nothing was added? */ | |
4539 | ret = -EINVAL; | |
4540 | goto out_unlock; | |
4541 | } | |
e1df4cb6 | 4542 | |
7b60f3d8 SRV |
4543 | ret = ftrace_hash_move_and_update_ops(&probe->ops, orig_hash, |
4544 | hash, 1); | |
1ec3a81a | 4545 | if (ret < 0) |
8d70725e | 4546 | goto err_unlock; |
8252ecf3 | 4547 | |
7b60f3d8 SRV |
4548 | /* One ref for each new function traced */ |
4549 | probe->ref += count; | |
8252ecf3 | 4550 | |
7b60f3d8 SRV |
4551 | if (!(probe->ops.flags & FTRACE_OPS_FL_ENABLED)) |
4552 | ret = ftrace_startup(&probe->ops, 0); | |
e1df4cb6 | 4553 | |
59df055f | 4554 | out_unlock: |
5ae0bf59 | 4555 | mutex_unlock(&ftrace_lock); |
8252ecf3 | 4556 | |
3296fc4e | 4557 | if (!ret) |
1ec3a81a | 4558 | ret = count; |
5ae0bf59 | 4559 | out: |
7b60f3d8 | 4560 | mutex_unlock(&probe->ops.func_hash->regex_lock); |
e1df4cb6 | 4561 | free_ftrace_hash(hash); |
59df055f | 4562 | |
7b60f3d8 | 4563 | release_probe(probe); |
59df055f | 4564 | |
1ec3a81a | 4565 | return ret; |
59df055f | 4566 | |
8d70725e | 4567 | err_unlock: |
7b60f3d8 | 4568 | if (!probe_ops->free || !count) |
8d70725e SRV |
4569 | goto out_unlock; |
4570 | ||
4571 | /* Failed to do the move, need to call the free functions */ | |
4572 | for (i = 0; i < size; i++) { | |
4573 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { | |
4574 | if (ftrace_lookup_ip(old_hash, entry->ip)) | |
4575 | continue; | |
6e444319 | 4576 | probe_ops->free(probe_ops, tr, entry->ip, probe->data); |
8d70725e SRV |
4577 | } |
4578 | } | |
4579 | goto out_unlock; | |
59df055f SR |
4580 | } |
4581 | ||
d3d532d7 | 4582 | int |
7b60f3d8 SRV |
4583 | unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr, |
4584 | struct ftrace_probe_ops *probe_ops) | |
59df055f | 4585 | { |
82cc4fc2 | 4586 | struct ftrace_ops_hash old_hash_ops; |
eee8ded1 | 4587 | struct ftrace_func_entry *entry; |
7b60f3d8 | 4588 | struct ftrace_func_probe *probe; |
3ba00929 | 4589 | struct ftrace_glob func_g; |
1ec3a81a SRV |
4590 | struct ftrace_hash **orig_hash; |
4591 | struct ftrace_hash *old_hash; | |
1ec3a81a | 4592 | struct ftrace_hash *hash = NULL; |
b67bfe0d | 4593 | struct hlist_node *tmp; |
eee8ded1 | 4594 | struct hlist_head hhd; |
59df055f | 4595 | char str[KSYM_SYMBOL_LEN]; |
7b60f3d8 SRV |
4596 | int count = 0; |
4597 | int i, ret = -ENODEV; | |
eee8ded1 | 4598 | int size; |
59df055f | 4599 | |
cbab567c | 4600 | if (!glob || !strlen(glob) || !strcmp(glob, "*")) |
3ba00929 | 4601 | func_g.search = NULL; |
cbab567c | 4602 | else { |
59df055f SR |
4603 | int not; |
4604 | ||
3ba00929 DS |
4605 | func_g.type = filter_parse_regex(glob, strlen(glob), |
4606 | &func_g.search, ¬); | |
4607 | func_g.len = strlen(func_g.search); | |
59df055f | 4608 | |
b6887d79 | 4609 | /* we do not support '!' for function probes */ |
59df055f | 4610 | if (WARN_ON(not)) |
d3d532d7 | 4611 | return -EINVAL; |
59df055f SR |
4612 | } |
4613 | ||
7b60f3d8 SRV |
4614 | mutex_lock(&ftrace_lock); |
4615 | /* Check if the probe_ops is already registered */ | |
4616 | list_for_each_entry(probe, &tr->func_probes, list) { | |
4617 | if (probe->probe_ops == probe_ops) | |
4618 | break; | |
59df055f | 4619 | } |
7b60f3d8 SRV |
4620 | if (&probe->list == &tr->func_probes) |
4621 | goto err_unlock_ftrace; | |
4622 | ||
4623 | ret = -EINVAL; | |
4624 | if (!(probe->ops.flags & FTRACE_OPS_FL_INITIALIZED)) | |
4625 | goto err_unlock_ftrace; | |
4626 | ||
4627 | acquire_probe_locked(probe); | |
4628 | ||
4629 | mutex_unlock(&ftrace_lock); | |
59df055f | 4630 | |
7b60f3d8 | 4631 | mutex_lock(&probe->ops.func_hash->regex_lock); |
1ec3a81a | 4632 | |
7b60f3d8 | 4633 | orig_hash = &probe->ops.func_hash->filter_hash; |
1ec3a81a SRV |
4634 | old_hash = *orig_hash; |
4635 | ||
1ec3a81a SRV |
4636 | if (ftrace_hash_empty(old_hash)) |
4637 | goto out_unlock; | |
e1df4cb6 | 4638 | |
82cc4fc2 SRV |
4639 | old_hash_ops.filter_hash = old_hash; |
4640 | /* Probes only have filters */ | |
4641 | old_hash_ops.notrace_hash = NULL; | |
4642 | ||
d3d532d7 | 4643 | ret = -ENOMEM; |
1ec3a81a | 4644 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash); |
e1df4cb6 | 4645 | if (!hash) |
e1df4cb6 SRRH |
4646 | goto out_unlock; |
4647 | ||
eee8ded1 | 4648 | INIT_HLIST_HEAD(&hhd); |
59df055f | 4649 | |
eee8ded1 SRV |
4650 | size = 1 << hash->size_bits; |
4651 | for (i = 0; i < size; i++) { | |
4652 | hlist_for_each_entry_safe(entry, tmp, &hash->buckets[i], hlist) { | |
59df055f | 4653 | |
3ba00929 | 4654 | if (func_g.search) { |
59df055f SR |
4655 | kallsyms_lookup(entry->ip, NULL, NULL, |
4656 | NULL, str); | |
3ba00929 | 4657 | if (!ftrace_match(str, &func_g)) |
59df055f SR |
4658 | continue; |
4659 | } | |
7b60f3d8 | 4660 | count++; |
eee8ded1 SRV |
4661 | remove_hash_entry(hash, entry); |
4662 | hlist_add_head(&entry->hlist, &hhd); | |
59df055f SR |
4663 | } |
4664 | } | |
d3d532d7 SRV |
4665 | |
4666 | /* Nothing found? */ | |
7b60f3d8 | 4667 | if (!count) { |
d3d532d7 SRV |
4668 | ret = -EINVAL; |
4669 | goto out_unlock; | |
4670 | } | |
4671 | ||
3f2367ba | 4672 | mutex_lock(&ftrace_lock); |
1ec3a81a | 4673 | |
7b60f3d8 | 4674 | WARN_ON(probe->ref < count); |
eee8ded1 | 4675 | |
7b60f3d8 | 4676 | probe->ref -= count; |
1ec3a81a | 4677 | |
7b60f3d8 SRV |
4678 | if (ftrace_hash_empty(hash)) |
4679 | ftrace_shutdown(&probe->ops, 0); | |
4680 | ||
4681 | ret = ftrace_hash_move_and_update_ops(&probe->ops, orig_hash, | |
1ec3a81a | 4682 | hash, 1); |
82cc4fc2 SRV |
4683 | |
4684 | /* still need to update the function call sites */ | |
1ec3a81a | 4685 | if (ftrace_enabled && !ftrace_hash_empty(hash)) |
7b60f3d8 | 4686 | ftrace_run_modify_code(&probe->ops, FTRACE_UPDATE_CALLS, |
82cc4fc2 | 4687 | &old_hash_ops); |
74401729 | 4688 | synchronize_rcu(); |
3296fc4e | 4689 | |
eee8ded1 SRV |
4690 | hlist_for_each_entry_safe(entry, tmp, &hhd, hlist) { |
4691 | hlist_del(&entry->hlist); | |
7b60f3d8 | 4692 | if (probe_ops->free) |
6e444319 | 4693 | probe_ops->free(probe_ops, tr, entry->ip, probe->data); |
eee8ded1 | 4694 | kfree(entry); |
7818b388 | 4695 | } |
3f2367ba | 4696 | mutex_unlock(&ftrace_lock); |
3ba00929 | 4697 | |
e1df4cb6 | 4698 | out_unlock: |
7b60f3d8 | 4699 | mutex_unlock(&probe->ops.func_hash->regex_lock); |
e1df4cb6 | 4700 | free_ftrace_hash(hash); |
59df055f | 4701 | |
7b60f3d8 | 4702 | release_probe(probe); |
59df055f | 4703 | |
7b60f3d8 | 4704 | return ret; |
59df055f | 4705 | |
7b60f3d8 SRV |
4706 | err_unlock_ftrace: |
4707 | mutex_unlock(&ftrace_lock); | |
d3d532d7 | 4708 | return ret; |
59df055f SR |
4709 | } |
4710 | ||
a0e6369e NR |
4711 | void clear_ftrace_function_probes(struct trace_array *tr) |
4712 | { | |
4713 | struct ftrace_func_probe *probe, *n; | |
4714 | ||
4715 | list_for_each_entry_safe(probe, n, &tr->func_probes, list) | |
4716 | unregister_ftrace_function_probe_func(NULL, tr, probe->probe_ops); | |
4717 | } | |
4718 | ||
f6180773 SR |
4719 | static LIST_HEAD(ftrace_commands); |
4720 | static DEFINE_MUTEX(ftrace_cmd_mutex); | |
4721 | ||
38de93ab TZ |
4722 | /* |
4723 | * Currently we only register ftrace commands from __init, so mark this | |
4724 | * __init too. | |
4725 | */ | |
4726 | __init int register_ftrace_command(struct ftrace_func_command *cmd) | |
f6180773 SR |
4727 | { |
4728 | struct ftrace_func_command *p; | |
4729 | int ret = 0; | |
4730 | ||
4731 | mutex_lock(&ftrace_cmd_mutex); | |
4732 | list_for_each_entry(p, &ftrace_commands, list) { | |
4733 | if (strcmp(cmd->name, p->name) == 0) { | |
4734 | ret = -EBUSY; | |
4735 | goto out_unlock; | |
4736 | } | |
4737 | } | |
4738 | list_add(&cmd->list, &ftrace_commands); | |
4739 | out_unlock: | |
4740 | mutex_unlock(&ftrace_cmd_mutex); | |
4741 | ||
4742 | return ret; | |
4743 | } | |
4744 | ||
38de93ab TZ |
4745 | /* |
4746 | * Currently we only unregister ftrace commands from __init, so mark | |
4747 | * this __init too. | |
4748 | */ | |
4749 | __init int unregister_ftrace_command(struct ftrace_func_command *cmd) | |
f6180773 SR |
4750 | { |
4751 | struct ftrace_func_command *p, *n; | |
4752 | int ret = -ENODEV; | |
4753 | ||
4754 | mutex_lock(&ftrace_cmd_mutex); | |
4755 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { | |
4756 | if (strcmp(cmd->name, p->name) == 0) { | |
4757 | ret = 0; | |
4758 | list_del_init(&p->list); | |
4759 | goto out_unlock; | |
4760 | } | |
4761 | } | |
4762 | out_unlock: | |
4763 | mutex_unlock(&ftrace_cmd_mutex); | |
4764 | ||
4765 | return ret; | |
4766 | } | |
4767 | ||
04ec7bb6 | 4768 | static int ftrace_process_regex(struct ftrace_iterator *iter, |
33dc9b12 | 4769 | char *buff, int len, int enable) |
64e7c440 | 4770 | { |
04ec7bb6 | 4771 | struct ftrace_hash *hash = iter->hash; |
d2afd57a | 4772 | struct trace_array *tr = iter->ops->private; |
f6180773 | 4773 | char *func, *command, *next = buff; |
6a24a244 | 4774 | struct ftrace_func_command *p; |
0aff1c0c | 4775 | int ret = -EINVAL; |
64e7c440 SR |
4776 | |
4777 | func = strsep(&next, ":"); | |
4778 | ||
4779 | if (!next) { | |
1cf41dd7 | 4780 | ret = ftrace_match_records(hash, func, len); |
b448c4e3 SR |
4781 | if (!ret) |
4782 | ret = -EINVAL; | |
4783 | if (ret < 0) | |
4784 | return ret; | |
4785 | return 0; | |
64e7c440 SR |
4786 | } |
4787 | ||
f6180773 | 4788 | /* command found */ |
64e7c440 SR |
4789 | |
4790 | command = strsep(&next, ":"); | |
4791 | ||
f6180773 SR |
4792 | mutex_lock(&ftrace_cmd_mutex); |
4793 | list_for_each_entry(p, &ftrace_commands, list) { | |
4794 | if (strcmp(p->name, command) == 0) { | |
04ec7bb6 | 4795 | ret = p->func(tr, hash, func, command, next, enable); |
f6180773 SR |
4796 | goto out_unlock; |
4797 | } | |
64e7c440 | 4798 | } |
f6180773 SR |
4799 | out_unlock: |
4800 | mutex_unlock(&ftrace_cmd_mutex); | |
64e7c440 | 4801 | |
f6180773 | 4802 | return ret; |
64e7c440 SR |
4803 | } |
4804 | ||
e309b41d | 4805 | static ssize_t |
41c52c0d SR |
4806 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
4807 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
4808 | { |
4809 | struct ftrace_iterator *iter; | |
689fd8b6 | 4810 | struct trace_parser *parser; |
4811 | ssize_t ret, read; | |
5072c59f | 4812 | |
4ba7978e | 4813 | if (!cnt) |
5072c59f SR |
4814 | return 0; |
4815 | ||
5072c59f SR |
4816 | if (file->f_mode & FMODE_READ) { |
4817 | struct seq_file *m = file->private_data; | |
4818 | iter = m->private; | |
4819 | } else | |
4820 | iter = file->private_data; | |
4821 | ||
f04f24fb | 4822 | if (unlikely(ftrace_disabled)) |
3f2367ba MH |
4823 | return -ENODEV; |
4824 | ||
4825 | /* iter->hash is a local copy, so we don't need regex_lock */ | |
f04f24fb | 4826 | |
689fd8b6 | 4827 | parser = &iter->parser; |
4828 | read = trace_get_user(parser, ubuf, cnt, ppos); | |
5072c59f | 4829 | |
4ba7978e | 4830 | if (read >= 0 && trace_parser_loaded(parser) && |
689fd8b6 | 4831 | !trace_parser_cont(parser)) { |
04ec7bb6 | 4832 | ret = ftrace_process_regex(iter, parser->buffer, |
689fd8b6 | 4833 | parser->idx, enable); |
313254a9 | 4834 | trace_parser_clear(parser); |
7c088b51 | 4835 | if (ret < 0) |
3f2367ba | 4836 | goto out; |
eda1e328 | 4837 | } |
5072c59f | 4838 | |
5072c59f | 4839 | ret = read; |
3f2367ba | 4840 | out: |
5072c59f SR |
4841 | return ret; |
4842 | } | |
4843 | ||
fc13cb0c | 4844 | ssize_t |
41c52c0d SR |
4845 | ftrace_filter_write(struct file *file, const char __user *ubuf, |
4846 | size_t cnt, loff_t *ppos) | |
4847 | { | |
4848 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
4849 | } | |
4850 | ||
fc13cb0c | 4851 | ssize_t |
41c52c0d SR |
4852 | ftrace_notrace_write(struct file *file, const char __user *ubuf, |
4853 | size_t cnt, loff_t *ppos) | |
4854 | { | |
4855 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
4856 | } | |
4857 | ||
33dc9b12 | 4858 | static int |
647664ea MH |
4859 | ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) |
4860 | { | |
4861 | struct ftrace_func_entry *entry; | |
4862 | ||
4863 | if (!ftrace_location(ip)) | |
4864 | return -EINVAL; | |
4865 | ||
4866 | if (remove) { | |
4867 | entry = ftrace_lookup_ip(hash, ip); | |
4868 | if (!entry) | |
4869 | return -ENOENT; | |
4870 | free_hash_entry(hash, entry); | |
4871 | return 0; | |
4872 | } | |
4873 | ||
4874 | return add_hash_entry(hash, ip); | |
4875 | } | |
4876 | ||
4877 | static int | |
4878 | ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, | |
4879 | unsigned long ip, int remove, int reset, int enable) | |
41c52c0d | 4880 | { |
33dc9b12 | 4881 | struct ftrace_hash **orig_hash; |
f45948e8 | 4882 | struct ftrace_hash *hash; |
33dc9b12 | 4883 | int ret; |
f45948e8 | 4884 | |
41c52c0d | 4885 | if (unlikely(ftrace_disabled)) |
33dc9b12 | 4886 | return -ENODEV; |
41c52c0d | 4887 | |
33b7f99c | 4888 | mutex_lock(&ops->func_hash->regex_lock); |
3f2367ba | 4889 | |
f45948e8 | 4890 | if (enable) |
33b7f99c | 4891 | orig_hash = &ops->func_hash->filter_hash; |
f45948e8 | 4892 | else |
33b7f99c | 4893 | orig_hash = &ops->func_hash->notrace_hash; |
33dc9b12 | 4894 | |
b972cc58 WN |
4895 | if (reset) |
4896 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); | |
4897 | else | |
4898 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
4899 | ||
3f2367ba MH |
4900 | if (!hash) { |
4901 | ret = -ENOMEM; | |
4902 | goto out_regex_unlock; | |
4903 | } | |
f45948e8 | 4904 | |
ac483c44 JO |
4905 | if (buf && !ftrace_match_records(hash, buf, len)) { |
4906 | ret = -EINVAL; | |
4907 | goto out_regex_unlock; | |
4908 | } | |
647664ea MH |
4909 | if (ip) { |
4910 | ret = ftrace_match_addr(hash, ip, remove); | |
4911 | if (ret < 0) | |
4912 | goto out_regex_unlock; | |
4913 | } | |
33dc9b12 SR |
4914 | |
4915 | mutex_lock(&ftrace_lock); | |
e16b35dd | 4916 | ret = ftrace_hash_move_and_update_ops(ops, orig_hash, hash, enable); |
33dc9b12 SR |
4917 | mutex_unlock(&ftrace_lock); |
4918 | ||
ac483c44 | 4919 | out_regex_unlock: |
33b7f99c | 4920 | mutex_unlock(&ops->func_hash->regex_lock); |
33dc9b12 SR |
4921 | |
4922 | free_ftrace_hash(hash); | |
4923 | return ret; | |
41c52c0d SR |
4924 | } |
4925 | ||
647664ea MH |
4926 | static int |
4927 | ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove, | |
4928 | int reset, int enable) | |
4929 | { | |
9efb85c5 | 4930 | return ftrace_set_hash(ops, NULL, 0, ip, remove, reset, enable); |
647664ea MH |
4931 | } |
4932 | ||
763e34e7 | 4933 | #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS |
013bf0da SRV |
4934 | |
4935 | struct ftrace_direct_func { | |
4936 | struct list_head next; | |
4937 | unsigned long addr; | |
4938 | int count; | |
4939 | }; | |
4940 | ||
4941 | static LIST_HEAD(ftrace_direct_funcs); | |
4942 | ||
4943 | /** | |
4944 | * ftrace_find_direct_func - test an address if it is a registered direct caller | |
4945 | * @addr: The address of a registered direct caller | |
4946 | * | |
4947 | * This searches to see if a ftrace direct caller has been registered | |
4948 | * at a specific address, and if so, it returns a descriptor for it. | |
4949 | * | |
4950 | * This can be used by architecture code to see if an address is | |
4951 | * a direct caller (trampoline) attached to a fentry/mcount location. | |
4952 | * This is useful for the function_graph tracer, as it may need to | |
4953 | * do adjustments if it traced a location that also has a direct | |
4954 | * trampoline attached to it. | |
4955 | */ | |
4956 | struct ftrace_direct_func *ftrace_find_direct_func(unsigned long addr) | |
4957 | { | |
4958 | struct ftrace_direct_func *entry; | |
4959 | bool found = false; | |
4960 | ||
4961 | /* May be called by fgraph trampoline (protected by rcu tasks) */ | |
4962 | list_for_each_entry_rcu(entry, &ftrace_direct_funcs, next) { | |
4963 | if (entry->addr == addr) { | |
4964 | found = true; | |
4965 | break; | |
4966 | } | |
4967 | } | |
4968 | if (found) | |
4969 | return entry; | |
4970 | ||
4971 | return NULL; | |
4972 | } | |
4973 | ||
763e34e7 SRV |
4974 | /** |
4975 | * register_ftrace_direct - Call a custom trampoline directly | |
4976 | * @ip: The address of the nop at the beginning of a function | |
4977 | * @addr: The address of the trampoline to call at @ip | |
4978 | * | |
4979 | * This is used to connect a direct call from the nop location (@ip) | |
4980 | * at the start of ftrace traced functions. The location that it calls | |
4981 | * (@addr) must be able to handle a direct call, and save the parameters | |
4982 | * of the function being traced, and restore them (or inject new ones | |
4983 | * if needed), before returning. | |
4984 | * | |
4985 | * Returns: | |
4986 | * 0 on success | |
4987 | * -EBUSY - Another direct function is already attached (there can be only one) | |
4988 | * -ENODEV - @ip does not point to a ftrace nop location (or not supported) | |
4989 | * -ENOMEM - There was an allocation failure. | |
4990 | */ | |
4991 | int register_ftrace_direct(unsigned long ip, unsigned long addr) | |
4992 | { | |
013bf0da | 4993 | struct ftrace_direct_func *direct; |
763e34e7 SRV |
4994 | struct ftrace_func_entry *entry; |
4995 | struct ftrace_hash *free_hash = NULL; | |
4996 | struct dyn_ftrace *rec; | |
4997 | int ret = -EBUSY; | |
4998 | ||
4999 | mutex_lock(&direct_mutex); | |
5000 | ||
5001 | /* See if there's a direct function at @ip already */ | |
ff205766 | 5002 | if (ftrace_find_rec_direct(ip)) |
763e34e7 SRV |
5003 | goto out_unlock; |
5004 | ||
5005 | ret = -ENODEV; | |
5006 | rec = lookup_rec(ip, ip); | |
5007 | if (!rec) | |
5008 | goto out_unlock; | |
5009 | ||
5010 | /* | |
5011 | * Check if the rec says it has a direct call but we didn't | |
5012 | * find one earlier? | |
5013 | */ | |
5014 | if (WARN_ON(rec->flags & FTRACE_FL_DIRECT)) | |
5015 | goto out_unlock; | |
5016 | ||
5017 | /* Make sure the ip points to the exact record */ | |
406acdd3 SRV |
5018 | if (ip != rec->ip) { |
5019 | ip = rec->ip; | |
5020 | /* Need to check this ip for a direct. */ | |
ff205766 | 5021 | if (ftrace_find_rec_direct(ip)) |
406acdd3 SRV |
5022 | goto out_unlock; |
5023 | } | |
763e34e7 SRV |
5024 | |
5025 | ret = -ENOMEM; | |
5026 | if (ftrace_hash_empty(direct_functions) || | |
5027 | direct_functions->count > 2 * (1 << direct_functions->size_bits)) { | |
5028 | struct ftrace_hash *new_hash; | |
5029 | int size = ftrace_hash_empty(direct_functions) ? 0 : | |
5030 | direct_functions->count + 1; | |
5031 | ||
5032 | if (size < 32) | |
5033 | size = 32; | |
5034 | ||
5035 | new_hash = dup_hash(direct_functions, size); | |
5036 | if (!new_hash) | |
5037 | goto out_unlock; | |
5038 | ||
5039 | free_hash = direct_functions; | |
5040 | direct_functions = new_hash; | |
5041 | } | |
5042 | ||
5043 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
5044 | if (!entry) | |
5045 | goto out_unlock; | |
5046 | ||
013bf0da SRV |
5047 | direct = ftrace_find_direct_func(addr); |
5048 | if (!direct) { | |
5049 | direct = kmalloc(sizeof(*direct), GFP_KERNEL); | |
5050 | if (!direct) { | |
5051 | kfree(entry); | |
5052 | goto out_unlock; | |
5053 | } | |
5054 | direct->addr = addr; | |
5055 | direct->count = 0; | |
5056 | list_add_rcu(&direct->next, &ftrace_direct_funcs); | |
a3ad1a7e | 5057 | ftrace_direct_func_count++; |
013bf0da SRV |
5058 | } |
5059 | ||
763e34e7 SRV |
5060 | entry->ip = ip; |
5061 | entry->direct = addr; | |
5062 | __add_hash_entry(direct_functions, entry); | |
5063 | ||
5064 | ret = ftrace_set_filter_ip(&direct_ops, ip, 0, 0); | |
5065 | if (ret) | |
5066 | remove_hash_entry(direct_functions, entry); | |
5067 | ||
5068 | if (!ret && !(direct_ops.flags & FTRACE_OPS_FL_ENABLED)) { | |
5069 | ret = register_ftrace_function(&direct_ops); | |
5070 | if (ret) | |
5071 | ftrace_set_filter_ip(&direct_ops, ip, 1, 0); | |
5072 | } | |
5073 | ||
013bf0da | 5074 | if (ret) { |
763e34e7 | 5075 | kfree(entry); |
013bf0da SRV |
5076 | if (!direct->count) { |
5077 | list_del_rcu(&direct->next); | |
5078 | synchronize_rcu_tasks(); | |
5079 | kfree(direct); | |
5080 | if (free_hash) | |
5081 | free_ftrace_hash(free_hash); | |
5082 | free_hash = NULL; | |
a3ad1a7e | 5083 | ftrace_direct_func_count--; |
013bf0da SRV |
5084 | } |
5085 | } else { | |
1c7f9b67 | 5086 | direct->count++; |
013bf0da | 5087 | } |
763e34e7 SRV |
5088 | out_unlock: |
5089 | mutex_unlock(&direct_mutex); | |
5090 | ||
5091 | if (free_hash) { | |
5092 | synchronize_rcu_tasks(); | |
5093 | free_ftrace_hash(free_hash); | |
5094 | } | |
5095 | ||
5096 | return ret; | |
5097 | } | |
5098 | EXPORT_SYMBOL_GPL(register_ftrace_direct); | |
5099 | ||
ea806eb3 SRV |
5100 | static struct ftrace_func_entry *find_direct_entry(unsigned long *ip, |
5101 | struct dyn_ftrace **recp) | |
763e34e7 SRV |
5102 | { |
5103 | struct ftrace_func_entry *entry; | |
5104 | struct dyn_ftrace *rec; | |
763e34e7 | 5105 | |
128161f4 SRV |
5106 | rec = lookup_rec(*ip, *ip); |
5107 | if (!rec) | |
5108 | return NULL; | |
763e34e7 | 5109 | |
128161f4 | 5110 | entry = __ftrace_lookup_ip(direct_functions, rec->ip); |
763e34e7 | 5111 | if (!entry) { |
128161f4 SRV |
5112 | WARN_ON(rec->flags & FTRACE_FL_DIRECT); |
5113 | return NULL; | |
5114 | } | |
763e34e7 | 5115 | |
128161f4 | 5116 | WARN_ON(!(rec->flags & FTRACE_FL_DIRECT)); |
763e34e7 | 5117 | |
128161f4 SRV |
5118 | /* Passed in ip just needs to be on the call site */ |
5119 | *ip = rec->ip; | |
5120 | ||
ea806eb3 SRV |
5121 | if (recp) |
5122 | *recp = rec; | |
5123 | ||
128161f4 SRV |
5124 | return entry; |
5125 | } | |
5126 | ||
5127 | int unregister_ftrace_direct(unsigned long ip, unsigned long addr) | |
5128 | { | |
5129 | struct ftrace_direct_func *direct; | |
5130 | struct ftrace_func_entry *entry; | |
5131 | int ret = -ENODEV; | |
5132 | ||
5133 | mutex_lock(&direct_mutex); | |
5134 | ||
ea806eb3 | 5135 | entry = find_direct_entry(&ip, NULL); |
128161f4 SRV |
5136 | if (!entry) |
5137 | goto out_unlock; | |
763e34e7 SRV |
5138 | |
5139 | if (direct_functions->count == 1) | |
5140 | unregister_ftrace_function(&direct_ops); | |
5141 | ||
5142 | ret = ftrace_set_filter_ip(&direct_ops, ip, 1, 0); | |
5143 | ||
5144 | WARN_ON(ret); | |
5145 | ||
5146 | remove_hash_entry(direct_functions, entry); | |
5147 | ||
013bf0da SRV |
5148 | direct = ftrace_find_direct_func(addr); |
5149 | if (!WARN_ON(!direct)) { | |
5150 | /* This is the good path (see the ! before WARN) */ | |
5151 | direct->count--; | |
5152 | WARN_ON(direct->count < 0); | |
5153 | if (!direct->count) { | |
5154 | list_del_rcu(&direct->next); | |
5155 | synchronize_rcu_tasks(); | |
5156 | kfree(direct); | |
a3ad1a7e | 5157 | ftrace_direct_func_count--; |
013bf0da SRV |
5158 | } |
5159 | } | |
763e34e7 SRV |
5160 | out_unlock: |
5161 | mutex_unlock(&direct_mutex); | |
5162 | ||
5163 | return ret; | |
5164 | } | |
5165 | EXPORT_SYMBOL_GPL(unregister_ftrace_direct); | |
0567d680 SRV |
5166 | |
5167 | static struct ftrace_ops stub_ops = { | |
5168 | .func = ftrace_stub, | |
5169 | }; | |
5170 | ||
ea806eb3 SRV |
5171 | /** |
5172 | * ftrace_modify_direct_caller - modify ftrace nop directly | |
5173 | * @entry: The ftrace hash entry of the direct helper for @rec | |
5174 | * @rec: The record representing the function site to patch | |
5175 | * @old_addr: The location that the site at @rec->ip currently calls | |
5176 | * @new_addr: The location that the site at @rec->ip should call | |
5177 | * | |
5178 | * An architecture may overwrite this function to optimize the | |
5179 | * changing of the direct callback on an ftrace nop location. | |
5180 | * This is called with the ftrace_lock mutex held, and no other | |
5181 | * ftrace callbacks are on the associated record (@rec). Thus, | |
5182 | * it is safe to modify the ftrace record, where it should be | |
5183 | * currently calling @old_addr directly, to call @new_addr. | |
5184 | * | |
5185 | * Safety checks should be made to make sure that the code at | |
5186 | * @rec->ip is currently calling @old_addr. And this must | |
5187 | * also update entry->direct to @new_addr. | |
5188 | */ | |
5189 | int __weak ftrace_modify_direct_caller(struct ftrace_func_entry *entry, | |
5190 | struct dyn_ftrace *rec, | |
5191 | unsigned long old_addr, | |
5192 | unsigned long new_addr) | |
5193 | { | |
5194 | unsigned long ip = rec->ip; | |
5195 | int ret; | |
5196 | ||
5197 | /* | |
5198 | * The ftrace_lock was used to determine if the record | |
5199 | * had more than one registered user to it. If it did, | |
5200 | * we needed to prevent that from changing to do the quick | |
5201 | * switch. But if it did not (only a direct caller was attached) | |
5202 | * then this function is called. But this function can deal | |
5203 | * with attached callers to the rec that we care about, and | |
5204 | * since this function uses standard ftrace calls that take | |
5205 | * the ftrace_lock mutex, we need to release it. | |
5206 | */ | |
5207 | mutex_unlock(&ftrace_lock); | |
5208 | ||
5209 | /* | |
5210 | * By setting a stub function at the same address, we force | |
5211 | * the code to call the iterator and the direct_ops helper. | |
5212 | * This means that @ip does not call the direct call, and | |
5213 | * we can simply modify it. | |
5214 | */ | |
5215 | ret = ftrace_set_filter_ip(&stub_ops, ip, 0, 0); | |
5216 | if (ret) | |
5217 | goto out_lock; | |
5218 | ||
5219 | ret = register_ftrace_function(&stub_ops); | |
5220 | if (ret) { | |
5221 | ftrace_set_filter_ip(&stub_ops, ip, 1, 0); | |
5222 | goto out_lock; | |
5223 | } | |
5224 | ||
5225 | entry->direct = new_addr; | |
5226 | ||
5227 | /* | |
5228 | * By removing the stub, we put back the direct call, calling | |
5229 | * the @new_addr. | |
5230 | */ | |
5231 | unregister_ftrace_function(&stub_ops); | |
5232 | ftrace_set_filter_ip(&stub_ops, ip, 1, 0); | |
5233 | ||
5234 | out_lock: | |
5235 | mutex_lock(&ftrace_lock); | |
5236 | ||
5237 | return ret; | |
5238 | } | |
5239 | ||
0567d680 SRV |
5240 | /** |
5241 | * modify_ftrace_direct - Modify an existing direct call to call something else | |
5242 | * @ip: The instruction pointer to modify | |
5243 | * @old_addr: The address that the current @ip calls directly | |
5244 | * @new_addr: The address that the @ip should call | |
5245 | * | |
5246 | * This modifies a ftrace direct caller at an instruction pointer without | |
5247 | * having to disable it first. The direct call will switch over to the | |
5248 | * @new_addr without missing anything. | |
5249 | * | |
5250 | * Returns: zero on success. Non zero on error, which includes: | |
5251 | * -ENODEV : the @ip given has no direct caller attached | |
5252 | * -EINVAL : the @old_addr does not match the current direct caller | |
5253 | */ | |
5254 | int modify_ftrace_direct(unsigned long ip, | |
5255 | unsigned long old_addr, unsigned long new_addr) | |
5256 | { | |
5257 | struct ftrace_func_entry *entry; | |
ea806eb3 | 5258 | struct dyn_ftrace *rec; |
0567d680 SRV |
5259 | int ret = -ENODEV; |
5260 | ||
5261 | mutex_lock(&direct_mutex); | |
0567d680 | 5262 | |
ea806eb3 SRV |
5263 | mutex_lock(&ftrace_lock); |
5264 | entry = find_direct_entry(&ip, &rec); | |
128161f4 SRV |
5265 | if (!entry) |
5266 | goto out_unlock; | |
0567d680 SRV |
5267 | |
5268 | ret = -EINVAL; | |
5269 | if (entry->direct != old_addr) | |
5270 | goto out_unlock; | |
5271 | ||
5272 | /* | |
ea806eb3 SRV |
5273 | * If there's no other ftrace callback on the rec->ip location, |
5274 | * then it can be changed directly by the architecture. | |
5275 | * If there is another caller, then we just need to change the | |
5276 | * direct caller helper to point to @new_addr. | |
0567d680 | 5277 | */ |
ea806eb3 SRV |
5278 | if (ftrace_rec_count(rec) == 1) { |
5279 | ret = ftrace_modify_direct_caller(entry, rec, old_addr, new_addr); | |
5280 | } else { | |
5281 | entry->direct = new_addr; | |
5282 | ret = 0; | |
0567d680 SRV |
5283 | } |
5284 | ||
0567d680 | 5285 | out_unlock: |
ea806eb3 | 5286 | mutex_unlock(&ftrace_lock); |
0567d680 SRV |
5287 | mutex_unlock(&direct_mutex); |
5288 | return ret; | |
5289 | } | |
5290 | EXPORT_SYMBOL_GPL(modify_ftrace_direct); | |
763e34e7 SRV |
5291 | #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */ |
5292 | ||
647664ea MH |
5293 | /** |
5294 | * ftrace_set_filter_ip - set a function to filter on in ftrace by address | |
5295 | * @ops - the ops to set the filter with | |
5296 | * @ip - the address to add to or remove from the filter. | |
5297 | * @remove - non zero to remove the ip from the filter | |
5298 | * @reset - non zero to reset all filters before applying this filter. | |
5299 | * | |
5300 | * Filters denote which functions should be enabled when tracing is enabled | |
5301 | * If @ip is NULL, it failes to update filter. | |
5302 | */ | |
5303 | int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, | |
5304 | int remove, int reset) | |
5305 | { | |
f04f24fb | 5306 | ftrace_ops_init(ops); |
647664ea MH |
5307 | return ftrace_set_addr(ops, ip, remove, reset, 1); |
5308 | } | |
5309 | EXPORT_SYMBOL_GPL(ftrace_set_filter_ip); | |
5310 | ||
d032ae89 JF |
5311 | /** |
5312 | * ftrace_ops_set_global_filter - setup ops to use global filters | |
5313 | * @ops - the ops which will use the global filters | |
5314 | * | |
5315 | * ftrace users who need global function trace filtering should call this. | |
5316 | * It can set the global filter only if ops were not initialized before. | |
5317 | */ | |
5318 | void ftrace_ops_set_global_filter(struct ftrace_ops *ops) | |
5319 | { | |
5320 | if (ops->flags & FTRACE_OPS_FL_INITIALIZED) | |
5321 | return; | |
5322 | ||
5323 | ftrace_ops_init(ops); | |
5324 | ops->func_hash = &global_ops.local_hash; | |
5325 | } | |
5326 | EXPORT_SYMBOL_GPL(ftrace_ops_set_global_filter); | |
5327 | ||
647664ea MH |
5328 | static int |
5329 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, | |
5330 | int reset, int enable) | |
5331 | { | |
5332 | return ftrace_set_hash(ops, buf, len, 0, 0, reset, enable); | |
5333 | } | |
5334 | ||
77a2b37d SR |
5335 | /** |
5336 | * ftrace_set_filter - set a function to filter on in ftrace | |
936e074b SR |
5337 | * @ops - the ops to set the filter with |
5338 | * @buf - the string that holds the function filter text. | |
5339 | * @len - the length of the string. | |
5340 | * @reset - non zero to reset all filters before applying this filter. | |
5341 | * | |
5342 | * Filters denote which functions should be enabled when tracing is enabled. | |
5343 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
5344 | */ | |
ac483c44 | 5345 | int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
5346 | int len, int reset) |
5347 | { | |
f04f24fb | 5348 | ftrace_ops_init(ops); |
ac483c44 | 5349 | return ftrace_set_regex(ops, buf, len, reset, 1); |
936e074b SR |
5350 | } |
5351 | EXPORT_SYMBOL_GPL(ftrace_set_filter); | |
5352 | ||
5353 | /** | |
5354 | * ftrace_set_notrace - set a function to not trace in ftrace | |
5355 | * @ops - the ops to set the notrace filter with | |
5356 | * @buf - the string that holds the function notrace text. | |
5357 | * @len - the length of the string. | |
5358 | * @reset - non zero to reset all filters before applying this filter. | |
5359 | * | |
5360 | * Notrace Filters denote which functions should not be enabled when tracing | |
5361 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
5362 | * for tracing. | |
5363 | */ | |
ac483c44 | 5364 | int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
5365 | int len, int reset) |
5366 | { | |
f04f24fb | 5367 | ftrace_ops_init(ops); |
ac483c44 | 5368 | return ftrace_set_regex(ops, buf, len, reset, 0); |
936e074b SR |
5369 | } |
5370 | EXPORT_SYMBOL_GPL(ftrace_set_notrace); | |
5371 | /** | |
8d1b065d | 5372 | * ftrace_set_global_filter - set a function to filter on with global tracers |
77a2b37d SR |
5373 | * @buf - the string that holds the function filter text. |
5374 | * @len - the length of the string. | |
5375 | * @reset - non zero to reset all filters before applying this filter. | |
5376 | * | |
5377 | * Filters denote which functions should be enabled when tracing is enabled. | |
5378 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
5379 | */ | |
936e074b | 5380 | void ftrace_set_global_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 5381 | { |
f45948e8 | 5382 | ftrace_set_regex(&global_ops, buf, len, reset, 1); |
41c52c0d | 5383 | } |
936e074b | 5384 | EXPORT_SYMBOL_GPL(ftrace_set_global_filter); |
4eebcc81 | 5385 | |
41c52c0d | 5386 | /** |
8d1b065d | 5387 | * ftrace_set_global_notrace - set a function to not trace with global tracers |
41c52c0d SR |
5388 | * @buf - the string that holds the function notrace text. |
5389 | * @len - the length of the string. | |
5390 | * @reset - non zero to reset all filters before applying this filter. | |
5391 | * | |
5392 | * Notrace Filters denote which functions should not be enabled when tracing | |
5393 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
5394 | * for tracing. | |
5395 | */ | |
936e074b | 5396 | void ftrace_set_global_notrace(unsigned char *buf, int len, int reset) |
41c52c0d | 5397 | { |
f45948e8 | 5398 | ftrace_set_regex(&global_ops, buf, len, reset, 0); |
77a2b37d | 5399 | } |
936e074b | 5400 | EXPORT_SYMBOL_GPL(ftrace_set_global_notrace); |
77a2b37d | 5401 | |
2af15d6a SR |
5402 | /* |
5403 | * command line interface to allow users to set filters on boot up. | |
5404 | */ | |
5405 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE | |
5406 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; | |
5407 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; | |
5408 | ||
f1ed7c74 SRRH |
5409 | /* Used by function selftest to not test if filter is set */ |
5410 | bool ftrace_filter_param __initdata; | |
5411 | ||
2af15d6a SR |
5412 | static int __init set_ftrace_notrace(char *str) |
5413 | { | |
f1ed7c74 | 5414 | ftrace_filter_param = true; |
75761cc1 | 5415 | strlcpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
5416 | return 1; |
5417 | } | |
5418 | __setup("ftrace_notrace=", set_ftrace_notrace); | |
5419 | ||
5420 | static int __init set_ftrace_filter(char *str) | |
5421 | { | |
f1ed7c74 | 5422 | ftrace_filter_param = true; |
75761cc1 | 5423 | strlcpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
5424 | return 1; |
5425 | } | |
5426 | __setup("ftrace_filter=", set_ftrace_filter); | |
5427 | ||
369bc18f | 5428 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
f6060f46 | 5429 | static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; |
0d7d9a16 | 5430 | static char ftrace_graph_notrace_buf[FTRACE_FILTER_SIZE] __initdata; |
b9b0c831 | 5431 | static int ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer); |
801c29fd | 5432 | |
369bc18f SA |
5433 | static int __init set_graph_function(char *str) |
5434 | { | |
06f43d66 | 5435 | strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); |
369bc18f SA |
5436 | return 1; |
5437 | } | |
5438 | __setup("ftrace_graph_filter=", set_graph_function); | |
5439 | ||
0d7d9a16 NK |
5440 | static int __init set_graph_notrace_function(char *str) |
5441 | { | |
5442 | strlcpy(ftrace_graph_notrace_buf, str, FTRACE_FILTER_SIZE); | |
5443 | return 1; | |
5444 | } | |
5445 | __setup("ftrace_graph_notrace=", set_graph_notrace_function); | |
5446 | ||
65a50c65 TB |
5447 | static int __init set_graph_max_depth_function(char *str) |
5448 | { | |
5449 | if (!str) | |
5450 | return 0; | |
5451 | fgraph_max_depth = simple_strtoul(str, NULL, 0); | |
5452 | return 1; | |
5453 | } | |
5454 | __setup("ftrace_graph_max_depth=", set_graph_max_depth_function); | |
0d7d9a16 NK |
5455 | |
5456 | static void __init set_ftrace_early_graph(char *buf, int enable) | |
369bc18f SA |
5457 | { |
5458 | int ret; | |
5459 | char *func; | |
b9b0c831 | 5460 | struct ftrace_hash *hash; |
0d7d9a16 | 5461 | |
92ad18ec | 5462 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); |
24589e3a | 5463 | if (MEM_FAIL(!hash, "Failed to allocate hash\n")) |
92ad18ec | 5464 | return; |
369bc18f SA |
5465 | |
5466 | while (buf) { | |
5467 | func = strsep(&buf, ","); | |
5468 | /* we allow only one expression at a time */ | |
b9b0c831 | 5469 | ret = ftrace_graph_set_hash(hash, func); |
369bc18f SA |
5470 | if (ret) |
5471 | printk(KERN_DEBUG "ftrace: function %s not " | |
5472 | "traceable\n", func); | |
5473 | } | |
92ad18ec SRV |
5474 | |
5475 | if (enable) | |
5476 | ftrace_graph_hash = hash; | |
5477 | else | |
5478 | ftrace_graph_notrace_hash = hash; | |
369bc18f SA |
5479 | } |
5480 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
5481 | ||
2a85a37f SR |
5482 | void __init |
5483 | ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable) | |
2af15d6a SR |
5484 | { |
5485 | char *func; | |
5486 | ||
f04f24fb MH |
5487 | ftrace_ops_init(ops); |
5488 | ||
2af15d6a SR |
5489 | while (buf) { |
5490 | func = strsep(&buf, ","); | |
f45948e8 | 5491 | ftrace_set_regex(ops, func, strlen(func), 0, enable); |
2af15d6a SR |
5492 | } |
5493 | } | |
5494 | ||
5495 | static void __init set_ftrace_early_filters(void) | |
5496 | { | |
5497 | if (ftrace_filter_buf[0]) | |
2a85a37f | 5498 | ftrace_set_early_filter(&global_ops, ftrace_filter_buf, 1); |
2af15d6a | 5499 | if (ftrace_notrace_buf[0]) |
2a85a37f | 5500 | ftrace_set_early_filter(&global_ops, ftrace_notrace_buf, 0); |
369bc18f SA |
5501 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5502 | if (ftrace_graph_buf[0]) | |
0d7d9a16 NK |
5503 | set_ftrace_early_graph(ftrace_graph_buf, 1); |
5504 | if (ftrace_graph_notrace_buf[0]) | |
5505 | set_ftrace_early_graph(ftrace_graph_notrace_buf, 0); | |
369bc18f | 5506 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
2af15d6a SR |
5507 | } |
5508 | ||
fc13cb0c | 5509 | int ftrace_regex_release(struct inode *inode, struct file *file) |
5072c59f SR |
5510 | { |
5511 | struct seq_file *m = (struct seq_file *)file->private_data; | |
5512 | struct ftrace_iterator *iter; | |
33dc9b12 | 5513 | struct ftrace_hash **orig_hash; |
689fd8b6 | 5514 | struct trace_parser *parser; |
ed926f9b | 5515 | int filter_hash; |
33dc9b12 | 5516 | int ret; |
5072c59f | 5517 | |
5072c59f SR |
5518 | if (file->f_mode & FMODE_READ) { |
5519 | iter = m->private; | |
5072c59f SR |
5520 | seq_release(inode, file); |
5521 | } else | |
5522 | iter = file->private_data; | |
5523 | ||
689fd8b6 | 5524 | parser = &iter->parser; |
5525 | if (trace_parser_loaded(parser)) { | |
1cf41dd7 | 5526 | ftrace_match_records(iter->hash, parser->buffer, parser->idx); |
5072c59f SR |
5527 | } |
5528 | ||
689fd8b6 | 5529 | trace_parser_put(parser); |
689fd8b6 | 5530 | |
33b7f99c | 5531 | mutex_lock(&iter->ops->func_hash->regex_lock); |
3f2367ba | 5532 | |
058e297d | 5533 | if (file->f_mode & FMODE_WRITE) { |
ed926f9b SR |
5534 | filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); |
5535 | ||
8c08f0d5 | 5536 | if (filter_hash) { |
33b7f99c | 5537 | orig_hash = &iter->ops->func_hash->filter_hash; |
69d71879 | 5538 | if (iter->tr && !list_empty(&iter->tr->mod_trace)) |
8c08f0d5 SRV |
5539 | iter->hash->flags |= FTRACE_HASH_FL_MOD; |
5540 | } else | |
33b7f99c | 5541 | orig_hash = &iter->ops->func_hash->notrace_hash; |
33dc9b12 | 5542 | |
058e297d | 5543 | mutex_lock(&ftrace_lock); |
e16b35dd SRV |
5544 | ret = ftrace_hash_move_and_update_ops(iter->ops, orig_hash, |
5545 | iter->hash, filter_hash); | |
058e297d | 5546 | mutex_unlock(&ftrace_lock); |
c20489da SRV |
5547 | } else { |
5548 | /* For read only, the hash is the ops hash */ | |
5549 | iter->hash = NULL; | |
058e297d | 5550 | } |
3f2367ba | 5551 | |
33b7f99c | 5552 | mutex_unlock(&iter->ops->func_hash->regex_lock); |
33dc9b12 | 5553 | free_ftrace_hash(iter->hash); |
9ef16693 SRV |
5554 | if (iter->tr) |
5555 | trace_array_put(iter->tr); | |
33dc9b12 | 5556 | kfree(iter); |
058e297d | 5557 | |
5072c59f SR |
5558 | return 0; |
5559 | } | |
5560 | ||
5e2336a0 | 5561 | static const struct file_operations ftrace_avail_fops = { |
5072c59f SR |
5562 | .open = ftrace_avail_open, |
5563 | .read = seq_read, | |
5564 | .llseek = seq_lseek, | |
3be04b47 | 5565 | .release = seq_release_private, |
5072c59f SR |
5566 | }; |
5567 | ||
647bcd03 SR |
5568 | static const struct file_operations ftrace_enabled_fops = { |
5569 | .open = ftrace_enabled_open, | |
5570 | .read = seq_read, | |
5571 | .llseek = seq_lseek, | |
5572 | .release = seq_release_private, | |
5573 | }; | |
5574 | ||
5e2336a0 | 5575 | static const struct file_operations ftrace_filter_fops = { |
5072c59f | 5576 | .open = ftrace_filter_open, |
850a80cf | 5577 | .read = seq_read, |
5072c59f | 5578 | .write = ftrace_filter_write, |
098c879e | 5579 | .llseek = tracing_lseek, |
1cf41dd7 | 5580 | .release = ftrace_regex_release, |
5072c59f SR |
5581 | }; |
5582 | ||
5e2336a0 | 5583 | static const struct file_operations ftrace_notrace_fops = { |
41c52c0d | 5584 | .open = ftrace_notrace_open, |
850a80cf | 5585 | .read = seq_read, |
41c52c0d | 5586 | .write = ftrace_notrace_write, |
098c879e | 5587 | .llseek = tracing_lseek, |
1cf41dd7 | 5588 | .release = ftrace_regex_release, |
41c52c0d SR |
5589 | }; |
5590 | ||
ea4e2bc4 SR |
5591 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5592 | ||
5593 | static DEFINE_MUTEX(graph_lock); | |
5594 | ||
24a9729f | 5595 | struct ftrace_hash __rcu *ftrace_graph_hash = EMPTY_HASH; |
fd0e6852 | 5596 | struct ftrace_hash __rcu *ftrace_graph_notrace_hash = EMPTY_HASH; |
b9b0c831 NK |
5597 | |
5598 | enum graph_filter_type { | |
5599 | GRAPH_FILTER_NOTRACE = 0, | |
5600 | GRAPH_FILTER_FUNCTION, | |
5601 | }; | |
ea4e2bc4 | 5602 | |
555fc781 SRV |
5603 | #define FTRACE_GRAPH_EMPTY ((void *)1) |
5604 | ||
faf982a6 | 5605 | struct ftrace_graph_data { |
e704eff3 SRV |
5606 | struct ftrace_hash *hash; |
5607 | struct ftrace_func_entry *entry; | |
5608 | int idx; /* for hash table iteration */ | |
5609 | enum graph_filter_type type; | |
5610 | struct ftrace_hash *new_hash; | |
5611 | const struct seq_operations *seq_ops; | |
5612 | struct trace_parser parser; | |
faf982a6 NK |
5613 | }; |
5614 | ||
ea4e2bc4 | 5615 | static void * |
85951842 | 5616 | __g_next(struct seq_file *m, loff_t *pos) |
ea4e2bc4 | 5617 | { |
faf982a6 | 5618 | struct ftrace_graph_data *fgd = m->private; |
b9b0c831 NK |
5619 | struct ftrace_func_entry *entry = fgd->entry; |
5620 | struct hlist_head *head; | |
5621 | int i, idx = fgd->idx; | |
faf982a6 | 5622 | |
b9b0c831 | 5623 | if (*pos >= fgd->hash->count) |
ea4e2bc4 | 5624 | return NULL; |
b9b0c831 NK |
5625 | |
5626 | if (entry) { | |
5627 | hlist_for_each_entry_continue(entry, hlist) { | |
5628 | fgd->entry = entry; | |
5629 | return entry; | |
5630 | } | |
5631 | ||
5632 | idx++; | |
5633 | } | |
5634 | ||
5635 | for (i = idx; i < 1 << fgd->hash->size_bits; i++) { | |
5636 | head = &fgd->hash->buckets[i]; | |
5637 | hlist_for_each_entry(entry, head, hlist) { | |
5638 | fgd->entry = entry; | |
5639 | fgd->idx = i; | |
5640 | return entry; | |
5641 | } | |
5642 | } | |
5643 | return NULL; | |
85951842 | 5644 | } |
ea4e2bc4 | 5645 | |
85951842 LZ |
5646 | static void * |
5647 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
5648 | { | |
5649 | (*pos)++; | |
5650 | return __g_next(m, pos); | |
ea4e2bc4 SR |
5651 | } |
5652 | ||
5653 | static void *g_start(struct seq_file *m, loff_t *pos) | |
5654 | { | |
faf982a6 NK |
5655 | struct ftrace_graph_data *fgd = m->private; |
5656 | ||
ea4e2bc4 SR |
5657 | mutex_lock(&graph_lock); |
5658 | ||
649b988b SRV |
5659 | if (fgd->type == GRAPH_FILTER_FUNCTION) |
5660 | fgd->hash = rcu_dereference_protected(ftrace_graph_hash, | |
5661 | lockdep_is_held(&graph_lock)); | |
5662 | else | |
5663 | fgd->hash = rcu_dereference_protected(ftrace_graph_notrace_hash, | |
5664 | lockdep_is_held(&graph_lock)); | |
5665 | ||
f9349a8f | 5666 | /* Nothing, tell g_show to print all functions are enabled */ |
b9b0c831 | 5667 | if (ftrace_hash_empty(fgd->hash) && !*pos) |
555fc781 | 5668 | return FTRACE_GRAPH_EMPTY; |
f9349a8f | 5669 | |
b9b0c831 NK |
5670 | fgd->idx = 0; |
5671 | fgd->entry = NULL; | |
85951842 | 5672 | return __g_next(m, pos); |
ea4e2bc4 SR |
5673 | } |
5674 | ||
5675 | static void g_stop(struct seq_file *m, void *p) | |
5676 | { | |
5677 | mutex_unlock(&graph_lock); | |
5678 | } | |
5679 | ||
5680 | static int g_show(struct seq_file *m, void *v) | |
5681 | { | |
b9b0c831 | 5682 | struct ftrace_func_entry *entry = v; |
ea4e2bc4 | 5683 | |
b9b0c831 | 5684 | if (!entry) |
ea4e2bc4 SR |
5685 | return 0; |
5686 | ||
555fc781 | 5687 | if (entry == FTRACE_GRAPH_EMPTY) { |
280d1429 NK |
5688 | struct ftrace_graph_data *fgd = m->private; |
5689 | ||
b9b0c831 | 5690 | if (fgd->type == GRAPH_FILTER_FUNCTION) |
fa6f0cc7 | 5691 | seq_puts(m, "#### all functions enabled ####\n"); |
280d1429 | 5692 | else |
fa6f0cc7 | 5693 | seq_puts(m, "#### no functions disabled ####\n"); |
f9349a8f FW |
5694 | return 0; |
5695 | } | |
5696 | ||
b9b0c831 | 5697 | seq_printf(m, "%ps\n", (void *)entry->ip); |
ea4e2bc4 SR |
5698 | |
5699 | return 0; | |
5700 | } | |
5701 | ||
88e9d34c | 5702 | static const struct seq_operations ftrace_graph_seq_ops = { |
ea4e2bc4 SR |
5703 | .start = g_start, |
5704 | .next = g_next, | |
5705 | .stop = g_stop, | |
5706 | .show = g_show, | |
5707 | }; | |
5708 | ||
5709 | static int | |
faf982a6 NK |
5710 | __ftrace_graph_open(struct inode *inode, struct file *file, |
5711 | struct ftrace_graph_data *fgd) | |
ea4e2bc4 | 5712 | { |
17911ff3 | 5713 | int ret; |
b9b0c831 | 5714 | struct ftrace_hash *new_hash = NULL; |
ea4e2bc4 | 5715 | |
17911ff3 SRV |
5716 | ret = security_locked_down(LOCKDOWN_TRACEFS); |
5717 | if (ret) | |
5718 | return ret; | |
5719 | ||
b9b0c831 NK |
5720 | if (file->f_mode & FMODE_WRITE) { |
5721 | const int size_bits = FTRACE_HASH_DEFAULT_BITS; | |
5722 | ||
e704eff3 SRV |
5723 | if (trace_parser_get_init(&fgd->parser, FTRACE_BUFF_MAX)) |
5724 | return -ENOMEM; | |
5725 | ||
b9b0c831 NK |
5726 | if (file->f_flags & O_TRUNC) |
5727 | new_hash = alloc_ftrace_hash(size_bits); | |
5728 | else | |
5729 | new_hash = alloc_and_copy_ftrace_hash(size_bits, | |
5730 | fgd->hash); | |
5731 | if (!new_hash) { | |
5732 | ret = -ENOMEM; | |
5733 | goto out; | |
5734 | } | |
ea4e2bc4 SR |
5735 | } |
5736 | ||
faf982a6 | 5737 | if (file->f_mode & FMODE_READ) { |
b9b0c831 | 5738 | ret = seq_open(file, &ftrace_graph_seq_ops); |
faf982a6 NK |
5739 | if (!ret) { |
5740 | struct seq_file *m = file->private_data; | |
5741 | m->private = fgd; | |
b9b0c831 NK |
5742 | } else { |
5743 | /* Failed */ | |
5744 | free_ftrace_hash(new_hash); | |
5745 | new_hash = NULL; | |
faf982a6 NK |
5746 | } |
5747 | } else | |
5748 | file->private_data = fgd; | |
ea4e2bc4 | 5749 | |
b9b0c831 | 5750 | out: |
e704eff3 SRV |
5751 | if (ret < 0 && file->f_mode & FMODE_WRITE) |
5752 | trace_parser_put(&fgd->parser); | |
5753 | ||
b9b0c831 | 5754 | fgd->new_hash = new_hash; |
649b988b SRV |
5755 | |
5756 | /* | |
5757 | * All uses of fgd->hash must be taken with the graph_lock | |
5758 | * held. The graph_lock is going to be released, so force | |
5759 | * fgd->hash to be reinitialized when it is taken again. | |
5760 | */ | |
5761 | fgd->hash = NULL; | |
5762 | ||
ea4e2bc4 SR |
5763 | return ret; |
5764 | } | |
5765 | ||
faf982a6 NK |
5766 | static int |
5767 | ftrace_graph_open(struct inode *inode, struct file *file) | |
5768 | { | |
5769 | struct ftrace_graph_data *fgd; | |
b9b0c831 | 5770 | int ret; |
faf982a6 NK |
5771 | |
5772 | if (unlikely(ftrace_disabled)) | |
5773 | return -ENODEV; | |
5774 | ||
5775 | fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); | |
5776 | if (fgd == NULL) | |
5777 | return -ENOMEM; | |
5778 | ||
b9b0c831 NK |
5779 | mutex_lock(&graph_lock); |
5780 | ||
649b988b SRV |
5781 | fgd->hash = rcu_dereference_protected(ftrace_graph_hash, |
5782 | lockdep_is_held(&graph_lock)); | |
b9b0c831 | 5783 | fgd->type = GRAPH_FILTER_FUNCTION; |
faf982a6 NK |
5784 | fgd->seq_ops = &ftrace_graph_seq_ops; |
5785 | ||
b9b0c831 NK |
5786 | ret = __ftrace_graph_open(inode, file, fgd); |
5787 | if (ret < 0) | |
5788 | kfree(fgd); | |
5789 | ||
5790 | mutex_unlock(&graph_lock); | |
5791 | return ret; | |
faf982a6 NK |
5792 | } |
5793 | ||
29ad23b0 NK |
5794 | static int |
5795 | ftrace_graph_notrace_open(struct inode *inode, struct file *file) | |
5796 | { | |
5797 | struct ftrace_graph_data *fgd; | |
b9b0c831 | 5798 | int ret; |
29ad23b0 NK |
5799 | |
5800 | if (unlikely(ftrace_disabled)) | |
5801 | return -ENODEV; | |
5802 | ||
5803 | fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); | |
5804 | if (fgd == NULL) | |
5805 | return -ENOMEM; | |
5806 | ||
b9b0c831 NK |
5807 | mutex_lock(&graph_lock); |
5808 | ||
649b988b SRV |
5809 | fgd->hash = rcu_dereference_protected(ftrace_graph_notrace_hash, |
5810 | lockdep_is_held(&graph_lock)); | |
b9b0c831 | 5811 | fgd->type = GRAPH_FILTER_NOTRACE; |
29ad23b0 NK |
5812 | fgd->seq_ops = &ftrace_graph_seq_ops; |
5813 | ||
b9b0c831 NK |
5814 | ret = __ftrace_graph_open(inode, file, fgd); |
5815 | if (ret < 0) | |
5816 | kfree(fgd); | |
5817 | ||
5818 | mutex_unlock(&graph_lock); | |
5819 | return ret; | |
29ad23b0 NK |
5820 | } |
5821 | ||
87827111 LZ |
5822 | static int |
5823 | ftrace_graph_release(struct inode *inode, struct file *file) | |
5824 | { | |
b9b0c831 | 5825 | struct ftrace_graph_data *fgd; |
e704eff3 SRV |
5826 | struct ftrace_hash *old_hash, *new_hash; |
5827 | struct trace_parser *parser; | |
5828 | int ret = 0; | |
b9b0c831 | 5829 | |
faf982a6 NK |
5830 | if (file->f_mode & FMODE_READ) { |
5831 | struct seq_file *m = file->private_data; | |
5832 | ||
b9b0c831 | 5833 | fgd = m->private; |
87827111 | 5834 | seq_release(inode, file); |
faf982a6 | 5835 | } else { |
b9b0c831 | 5836 | fgd = file->private_data; |
faf982a6 NK |
5837 | } |
5838 | ||
e704eff3 SRV |
5839 | |
5840 | if (file->f_mode & FMODE_WRITE) { | |
5841 | ||
5842 | parser = &fgd->parser; | |
5843 | ||
5844 | if (trace_parser_loaded((parser))) { | |
e704eff3 SRV |
5845 | ret = ftrace_graph_set_hash(fgd->new_hash, |
5846 | parser->buffer); | |
5847 | } | |
5848 | ||
5849 | trace_parser_put(parser); | |
5850 | ||
5851 | new_hash = __ftrace_hash_move(fgd->new_hash); | |
5852 | if (!new_hash) { | |
5853 | ret = -ENOMEM; | |
5854 | goto out; | |
5855 | } | |
5856 | ||
5857 | mutex_lock(&graph_lock); | |
5858 | ||
5859 | if (fgd->type == GRAPH_FILTER_FUNCTION) { | |
5860 | old_hash = rcu_dereference_protected(ftrace_graph_hash, | |
5861 | lockdep_is_held(&graph_lock)); | |
5862 | rcu_assign_pointer(ftrace_graph_hash, new_hash); | |
5863 | } else { | |
5864 | old_hash = rcu_dereference_protected(ftrace_graph_notrace_hash, | |
5865 | lockdep_is_held(&graph_lock)); | |
5866 | rcu_assign_pointer(ftrace_graph_notrace_hash, new_hash); | |
5867 | } | |
5868 | ||
5869 | mutex_unlock(&graph_lock); | |
5870 | ||
54a16ff6 SRV |
5871 | /* |
5872 | * We need to do a hard force of sched synchronization. | |
5873 | * This is because we use preempt_disable() to do RCU, but | |
5874 | * the function tracers can be called where RCU is not watching | |
5875 | * (like before user_exit()). We can not rely on the RCU | |
5876 | * infrastructure to do the synchronization, thus we must do it | |
5877 | * ourselves. | |
5878 | */ | |
e5a971d7 | 5879 | synchronize_rcu_tasks_rude(); |
e704eff3 SRV |
5880 | |
5881 | free_ftrace_hash(old_hash); | |
5882 | } | |
5883 | ||
5884 | out: | |
f9797c2f | 5885 | free_ftrace_hash(fgd->new_hash); |
b9b0c831 NK |
5886 | kfree(fgd); |
5887 | ||
e704eff3 | 5888 | return ret; |
87827111 LZ |
5889 | } |
5890 | ||
ea4e2bc4 | 5891 | static int |
b9b0c831 | 5892 | ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer) |
ea4e2bc4 | 5893 | { |
3ba00929 | 5894 | struct ftrace_glob func_g; |
ea4e2bc4 SR |
5895 | struct dyn_ftrace *rec; |
5896 | struct ftrace_page *pg; | |
b9b0c831 | 5897 | struct ftrace_func_entry *entry; |
c7c6b1fe | 5898 | int fail = 1; |
3ba00929 | 5899 | int not; |
ea4e2bc4 | 5900 | |
f9349a8f | 5901 | /* decode regex */ |
3ba00929 DS |
5902 | func_g.type = filter_parse_regex(buffer, strlen(buffer), |
5903 | &func_g.search, ¬); | |
f9349a8f | 5904 | |
3ba00929 | 5905 | func_g.len = strlen(func_g.search); |
f9349a8f | 5906 | |
52baf119 | 5907 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
5908 | |
5909 | if (unlikely(ftrace_disabled)) { | |
5910 | mutex_unlock(&ftrace_lock); | |
5911 | return -ENODEV; | |
5912 | } | |
5913 | ||
265c831c SR |
5914 | do_for_each_ftrace_rec(pg, rec) { |
5915 | ||
546fece4 SRRH |
5916 | if (rec->flags & FTRACE_FL_DISABLED) |
5917 | continue; | |
5918 | ||
0b507e1e | 5919 | if (ftrace_match_record(rec, &func_g, NULL, 0)) { |
b9b0c831 | 5920 | entry = ftrace_lookup_ip(hash, rec->ip); |
c7c6b1fe LZ |
5921 | |
5922 | if (!not) { | |
5923 | fail = 0; | |
b9b0c831 NK |
5924 | |
5925 | if (entry) | |
5926 | continue; | |
5927 | if (add_hash_entry(hash, rec->ip) < 0) | |
5928 | goto out; | |
c7c6b1fe | 5929 | } else { |
b9b0c831 NK |
5930 | if (entry) { |
5931 | free_hash_entry(hash, entry); | |
c7c6b1fe LZ |
5932 | fail = 0; |
5933 | } | |
5934 | } | |
ea4e2bc4 | 5935 | } |
265c831c | 5936 | } while_for_each_ftrace_rec(); |
c7c6b1fe | 5937 | out: |
52baf119 | 5938 | mutex_unlock(&ftrace_lock); |
ea4e2bc4 | 5939 | |
c7c6b1fe LZ |
5940 | if (fail) |
5941 | return -EINVAL; | |
5942 | ||
c7c6b1fe | 5943 | return 0; |
ea4e2bc4 SR |
5944 | } |
5945 | ||
5946 | static ssize_t | |
5947 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
5948 | size_t cnt, loff_t *ppos) | |
5949 | { | |
6a10108b | 5950 | ssize_t read, ret = 0; |
faf982a6 | 5951 | struct ftrace_graph_data *fgd = file->private_data; |
e704eff3 | 5952 | struct trace_parser *parser; |
ea4e2bc4 | 5953 | |
c7c6b1fe | 5954 | if (!cnt) |
ea4e2bc4 SR |
5955 | return 0; |
5956 | ||
ae98d27a SRV |
5957 | /* Read mode uses seq functions */ |
5958 | if (file->f_mode & FMODE_READ) { | |
5959 | struct seq_file *m = file->private_data; | |
5960 | fgd = m->private; | |
5961 | } | |
5962 | ||
e704eff3 | 5963 | parser = &fgd->parser; |
ea4e2bc4 | 5964 | |
e704eff3 | 5965 | read = trace_get_user(parser, ubuf, cnt, ppos); |
689fd8b6 | 5966 | |
e704eff3 SRV |
5967 | if (read >= 0 && trace_parser_loaded(parser) && |
5968 | !trace_parser_cont(parser)) { | |
6a10108b | 5969 | |
b9b0c831 | 5970 | ret = ftrace_graph_set_hash(fgd->new_hash, |
e704eff3 SRV |
5971 | parser->buffer); |
5972 | trace_parser_clear(parser); | |
ea4e2bc4 | 5973 | } |
ea4e2bc4 | 5974 | |
6a10108b NK |
5975 | if (!ret) |
5976 | ret = read; | |
1eb90f13 | 5977 | |
ea4e2bc4 SR |
5978 | return ret; |
5979 | } | |
5980 | ||
5981 | static const struct file_operations ftrace_graph_fops = { | |
87827111 LZ |
5982 | .open = ftrace_graph_open, |
5983 | .read = seq_read, | |
5984 | .write = ftrace_graph_write, | |
098c879e | 5985 | .llseek = tracing_lseek, |
87827111 | 5986 | .release = ftrace_graph_release, |
ea4e2bc4 | 5987 | }; |
29ad23b0 NK |
5988 | |
5989 | static const struct file_operations ftrace_graph_notrace_fops = { | |
5990 | .open = ftrace_graph_notrace_open, | |
5991 | .read = seq_read, | |
5992 | .write = ftrace_graph_write, | |
098c879e | 5993 | .llseek = tracing_lseek, |
29ad23b0 NK |
5994 | .release = ftrace_graph_release, |
5995 | }; | |
ea4e2bc4 SR |
5996 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
5997 | ||
591dffda SRRH |
5998 | void ftrace_create_filter_files(struct ftrace_ops *ops, |
5999 | struct dentry *parent) | |
6000 | { | |
6001 | ||
6002 | trace_create_file("set_ftrace_filter", 0644, parent, | |
6003 | ops, &ftrace_filter_fops); | |
6004 | ||
6005 | trace_create_file("set_ftrace_notrace", 0644, parent, | |
6006 | ops, &ftrace_notrace_fops); | |
6007 | } | |
6008 | ||
6009 | /* | |
6010 | * The name "destroy_filter_files" is really a misnomer. Although | |
9efb85c5 | 6011 | * in the future, it may actually delete the files, but this is |
591dffda SRRH |
6012 | * really intended to make sure the ops passed in are disabled |
6013 | * and that when this function returns, the caller is free to | |
6014 | * free the ops. | |
6015 | * | |
6016 | * The "destroy" name is only to match the "create" name that this | |
6017 | * should be paired with. | |
6018 | */ | |
6019 | void ftrace_destroy_filter_files(struct ftrace_ops *ops) | |
6020 | { | |
6021 | mutex_lock(&ftrace_lock); | |
6022 | if (ops->flags & FTRACE_OPS_FL_ENABLED) | |
6023 | ftrace_shutdown(ops, 0); | |
6024 | ops->flags |= FTRACE_OPS_FL_DELETED; | |
2840f84f | 6025 | ftrace_free_filter(ops); |
591dffda SRRH |
6026 | mutex_unlock(&ftrace_lock); |
6027 | } | |
6028 | ||
8434dc93 | 6029 | static __init int ftrace_init_dyn_tracefs(struct dentry *d_tracer) |
5072c59f | 6030 | { |
5072c59f | 6031 | |
5452af66 FW |
6032 | trace_create_file("available_filter_functions", 0444, |
6033 | d_tracer, NULL, &ftrace_avail_fops); | |
5072c59f | 6034 | |
647bcd03 SR |
6035 | trace_create_file("enabled_functions", 0444, |
6036 | d_tracer, NULL, &ftrace_enabled_fops); | |
6037 | ||
591dffda | 6038 | ftrace_create_filter_files(&global_ops, d_tracer); |
ad90c0e3 | 6039 | |
ea4e2bc4 | 6040 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
1ce0500d | 6041 | trace_create_file("set_graph_function", 0644, d_tracer, |
ea4e2bc4 SR |
6042 | NULL, |
6043 | &ftrace_graph_fops); | |
1ce0500d | 6044 | trace_create_file("set_graph_notrace", 0644, d_tracer, |
29ad23b0 NK |
6045 | NULL, |
6046 | &ftrace_graph_notrace_fops); | |
ea4e2bc4 SR |
6047 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
6048 | ||
5072c59f SR |
6049 | return 0; |
6050 | } | |
6051 | ||
9fd49328 | 6052 | static int ftrace_cmp_ips(const void *a, const void *b) |
68950619 | 6053 | { |
9fd49328 SR |
6054 | const unsigned long *ipa = a; |
6055 | const unsigned long *ipb = b; | |
68950619 | 6056 | |
9fd49328 SR |
6057 | if (*ipa > *ipb) |
6058 | return 1; | |
6059 | if (*ipa < *ipb) | |
6060 | return -1; | |
6061 | return 0; | |
6062 | } | |
6063 | ||
5cb084bb | 6064 | static int ftrace_process_locs(struct module *mod, |
31e88909 | 6065 | unsigned long *start, |
68bf21aa SR |
6066 | unsigned long *end) |
6067 | { | |
706c81f8 | 6068 | struct ftrace_page *start_pg; |
a7900875 | 6069 | struct ftrace_page *pg; |
706c81f8 | 6070 | struct dyn_ftrace *rec; |
a7900875 | 6071 | unsigned long count; |
68bf21aa SR |
6072 | unsigned long *p; |
6073 | unsigned long addr; | |
4376cac6 | 6074 | unsigned long flags = 0; /* Shut up gcc */ |
a7900875 SR |
6075 | int ret = -ENOMEM; |
6076 | ||
6077 | count = end - start; | |
6078 | ||
6079 | if (!count) | |
6080 | return 0; | |
6081 | ||
9fd49328 | 6082 | sort(start, count, sizeof(*start), |
6db02903 | 6083 | ftrace_cmp_ips, NULL); |
9fd49328 | 6084 | |
706c81f8 SR |
6085 | start_pg = ftrace_allocate_pages(count); |
6086 | if (!start_pg) | |
a7900875 | 6087 | return -ENOMEM; |
68bf21aa | 6088 | |
e6ea44e9 | 6089 | mutex_lock(&ftrace_lock); |
a7900875 | 6090 | |
32082309 SR |
6091 | /* |
6092 | * Core and each module needs their own pages, as | |
6093 | * modules will free them when they are removed. | |
6094 | * Force a new page to be allocated for modules. | |
6095 | */ | |
a7900875 SR |
6096 | if (!mod) { |
6097 | WARN_ON(ftrace_pages || ftrace_pages_start); | |
6098 | /* First initialization */ | |
706c81f8 | 6099 | ftrace_pages = ftrace_pages_start = start_pg; |
a7900875 | 6100 | } else { |
32082309 | 6101 | if (!ftrace_pages) |
a7900875 | 6102 | goto out; |
32082309 | 6103 | |
a7900875 SR |
6104 | if (WARN_ON(ftrace_pages->next)) { |
6105 | /* Hmm, we have free pages? */ | |
6106 | while (ftrace_pages->next) | |
6107 | ftrace_pages = ftrace_pages->next; | |
32082309 | 6108 | } |
a7900875 | 6109 | |
706c81f8 | 6110 | ftrace_pages->next = start_pg; |
32082309 SR |
6111 | } |
6112 | ||
68bf21aa | 6113 | p = start; |
706c81f8 | 6114 | pg = start_pg; |
68bf21aa SR |
6115 | while (p < end) { |
6116 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
6117 | /* |
6118 | * Some architecture linkers will pad between | |
6119 | * the different mcount_loc sections of different | |
6120 | * object files to satisfy alignments. | |
6121 | * Skip any NULL pointers. | |
6122 | */ | |
6123 | if (!addr) | |
6124 | continue; | |
706c81f8 SR |
6125 | |
6126 | if (pg->index == pg->size) { | |
6127 | /* We should have allocated enough */ | |
6128 | if (WARN_ON(!pg->next)) | |
6129 | break; | |
6130 | pg = pg->next; | |
6131 | } | |
6132 | ||
6133 | rec = &pg->records[pg->index++]; | |
6134 | rec->ip = addr; | |
68bf21aa SR |
6135 | } |
6136 | ||
706c81f8 SR |
6137 | /* We should have used all pages */ |
6138 | WARN_ON(pg->next); | |
6139 | ||
6140 | /* Assign the last page to ftrace_pages */ | |
6141 | ftrace_pages = pg; | |
6142 | ||
a4f18ed1 | 6143 | /* |
4376cac6 SR |
6144 | * We only need to disable interrupts on start up |
6145 | * because we are modifying code that an interrupt | |
6146 | * may execute, and the modification is not atomic. | |
6147 | * But for modules, nothing runs the code we modify | |
6148 | * until we are finished with it, and there's no | |
6149 | * reason to cause large interrupt latencies while we do it. | |
a4f18ed1 | 6150 | */ |
4376cac6 SR |
6151 | if (!mod) |
6152 | local_irq_save(flags); | |
1dc43cf0 | 6153 | ftrace_update_code(mod, start_pg); |
4376cac6 SR |
6154 | if (!mod) |
6155 | local_irq_restore(flags); | |
a7900875 SR |
6156 | ret = 0; |
6157 | out: | |
e6ea44e9 | 6158 | mutex_unlock(&ftrace_lock); |
68bf21aa | 6159 | |
a7900875 | 6160 | return ret; |
68bf21aa SR |
6161 | } |
6162 | ||
aba4b5c2 SRV |
6163 | struct ftrace_mod_func { |
6164 | struct list_head list; | |
6165 | char *name; | |
6166 | unsigned long ip; | |
6167 | unsigned int size; | |
6168 | }; | |
6169 | ||
6170 | struct ftrace_mod_map { | |
6aa69784 | 6171 | struct rcu_head rcu; |
aba4b5c2 SRV |
6172 | struct list_head list; |
6173 | struct module *mod; | |
6174 | unsigned long start_addr; | |
6175 | unsigned long end_addr; | |
6176 | struct list_head funcs; | |
6171a031 | 6177 | unsigned int num_funcs; |
aba4b5c2 SRV |
6178 | }; |
6179 | ||
93eb677d | 6180 | #ifdef CONFIG_MODULES |
32082309 SR |
6181 | |
6182 | #define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next) | |
6183 | ||
6aa69784 SRV |
6184 | static LIST_HEAD(ftrace_mod_maps); |
6185 | ||
b7ffffbb SRRH |
6186 | static int referenced_filters(struct dyn_ftrace *rec) |
6187 | { | |
6188 | struct ftrace_ops *ops; | |
6189 | int cnt = 0; | |
6190 | ||
6191 | for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) { | |
6192 | if (ops_references_rec(ops, rec)) | |
6193 | cnt++; | |
6194 | } | |
6195 | ||
6196 | return cnt; | |
6197 | } | |
6198 | ||
2a5bfe47 SRV |
6199 | static void |
6200 | clear_mod_from_hash(struct ftrace_page *pg, struct ftrace_hash *hash) | |
6201 | { | |
6202 | struct ftrace_func_entry *entry; | |
6203 | struct dyn_ftrace *rec; | |
6204 | int i; | |
6205 | ||
6206 | if (ftrace_hash_empty(hash)) | |
6207 | return; | |
6208 | ||
6209 | for (i = 0; i < pg->index; i++) { | |
6210 | rec = &pg->records[i]; | |
6211 | entry = __ftrace_lookup_ip(hash, rec->ip); | |
6212 | /* | |
6213 | * Do not allow this rec to match again. | |
6214 | * Yeah, it may waste some memory, but will be removed | |
6215 | * if/when the hash is modified again. | |
6216 | */ | |
6217 | if (entry) | |
6218 | entry->ip = 0; | |
6219 | } | |
6220 | } | |
6221 | ||
6222 | /* Clear any records from hashs */ | |
6223 | static void clear_mod_from_hashes(struct ftrace_page *pg) | |
6224 | { | |
6225 | struct trace_array *tr; | |
6226 | ||
6227 | mutex_lock(&trace_types_lock); | |
6228 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6229 | if (!tr->ops || !tr->ops->func_hash) | |
6230 | continue; | |
6231 | mutex_lock(&tr->ops->func_hash->regex_lock); | |
6232 | clear_mod_from_hash(pg, tr->ops->func_hash->filter_hash); | |
6233 | clear_mod_from_hash(pg, tr->ops->func_hash->notrace_hash); | |
6234 | mutex_unlock(&tr->ops->func_hash->regex_lock); | |
6235 | } | |
6236 | mutex_unlock(&trace_types_lock); | |
6237 | } | |
6238 | ||
6aa69784 SRV |
6239 | static void ftrace_free_mod_map(struct rcu_head *rcu) |
6240 | { | |
6241 | struct ftrace_mod_map *mod_map = container_of(rcu, struct ftrace_mod_map, rcu); | |
6242 | struct ftrace_mod_func *mod_func; | |
6243 | struct ftrace_mod_func *n; | |
6244 | ||
6245 | /* All the contents of mod_map are now not visible to readers */ | |
6246 | list_for_each_entry_safe(mod_func, n, &mod_map->funcs, list) { | |
6247 | kfree(mod_func->name); | |
6248 | list_del(&mod_func->list); | |
6249 | kfree(mod_func); | |
6250 | } | |
6251 | ||
6252 | kfree(mod_map); | |
6253 | } | |
6254 | ||
e7247a15 | 6255 | void ftrace_release_mod(struct module *mod) |
93eb677d | 6256 | { |
6aa69784 SRV |
6257 | struct ftrace_mod_map *mod_map; |
6258 | struct ftrace_mod_map *n; | |
93eb677d | 6259 | struct dyn_ftrace *rec; |
32082309 | 6260 | struct ftrace_page **last_pg; |
2a5bfe47 | 6261 | struct ftrace_page *tmp_page = NULL; |
93eb677d | 6262 | struct ftrace_page *pg; |
a7900875 | 6263 | int order; |
93eb677d | 6264 | |
45a4a237 SR |
6265 | mutex_lock(&ftrace_lock); |
6266 | ||
e7247a15 | 6267 | if (ftrace_disabled) |
45a4a237 | 6268 | goto out_unlock; |
93eb677d | 6269 | |
6aa69784 SRV |
6270 | list_for_each_entry_safe(mod_map, n, &ftrace_mod_maps, list) { |
6271 | if (mod_map->mod == mod) { | |
6272 | list_del_rcu(&mod_map->list); | |
74401729 | 6273 | call_rcu(&mod_map->rcu, ftrace_free_mod_map); |
6aa69784 SRV |
6274 | break; |
6275 | } | |
6276 | } | |
6277 | ||
32082309 SR |
6278 | /* |
6279 | * Each module has its own ftrace_pages, remove | |
6280 | * them from the list. | |
6281 | */ | |
6282 | last_pg = &ftrace_pages_start; | |
6283 | for (pg = ftrace_pages_start; pg; pg = *last_pg) { | |
6284 | rec = &pg->records[0]; | |
3e234289 SRV |
6285 | if (within_module_core(rec->ip, mod) || |
6286 | within_module_init(rec->ip, mod)) { | |
93eb677d | 6287 | /* |
32082309 SR |
6288 | * As core pages are first, the first |
6289 | * page should never be a module page. | |
93eb677d | 6290 | */ |
32082309 SR |
6291 | if (WARN_ON(pg == ftrace_pages_start)) |
6292 | goto out_unlock; | |
6293 | ||
6294 | /* Check if we are deleting the last page */ | |
6295 | if (pg == ftrace_pages) | |
6296 | ftrace_pages = next_to_ftrace_page(last_pg); | |
6297 | ||
83dd1493 | 6298 | ftrace_update_tot_cnt -= pg->index; |
32082309 | 6299 | *last_pg = pg->next; |
2a5bfe47 SRV |
6300 | |
6301 | pg->next = tmp_page; | |
6302 | tmp_page = pg; | |
32082309 SR |
6303 | } else |
6304 | last_pg = &pg->next; | |
6305 | } | |
45a4a237 | 6306 | out_unlock: |
93eb677d | 6307 | mutex_unlock(&ftrace_lock); |
2a5bfe47 SRV |
6308 | |
6309 | for (pg = tmp_page; pg; pg = tmp_page) { | |
6310 | ||
6311 | /* Needs to be called outside of ftrace_lock */ | |
6312 | clear_mod_from_hashes(pg); | |
6313 | ||
6314 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); | |
6315 | free_pages((unsigned long)pg->records, order); | |
6316 | tmp_page = pg->next; | |
6317 | kfree(pg); | |
da537f0a SRV |
6318 | ftrace_number_of_pages -= 1 << order; |
6319 | ftrace_number_of_groups--; | |
2a5bfe47 | 6320 | } |
93eb677d SR |
6321 | } |
6322 | ||
7dcd182b | 6323 | void ftrace_module_enable(struct module *mod) |
b7ffffbb SRRH |
6324 | { |
6325 | struct dyn_ftrace *rec; | |
6326 | struct ftrace_page *pg; | |
6327 | ||
6328 | mutex_lock(&ftrace_lock); | |
6329 | ||
6330 | if (ftrace_disabled) | |
6331 | goto out_unlock; | |
6332 | ||
6333 | /* | |
6334 | * If the tracing is enabled, go ahead and enable the record. | |
6335 | * | |
9efb85c5 | 6336 | * The reason not to enable the record immediately is the |
b7ffffbb SRRH |
6337 | * inherent check of ftrace_make_nop/ftrace_make_call for |
6338 | * correct previous instructions. Making first the NOP | |
6339 | * conversion puts the module to the correct state, thus | |
6340 | * passing the ftrace_make_call check. | |
6341 | * | |
6342 | * We also delay this to after the module code already set the | |
6343 | * text to read-only, as we now need to set it back to read-write | |
6344 | * so that we can modify the text. | |
6345 | */ | |
6346 | if (ftrace_start_up) | |
6347 | ftrace_arch_code_modify_prepare(); | |
6348 | ||
6349 | do_for_each_ftrace_rec(pg, rec) { | |
6350 | int cnt; | |
6351 | /* | |
6352 | * do_for_each_ftrace_rec() is a double loop. | |
6353 | * module text shares the pg. If a record is | |
6354 | * not part of this module, then skip this pg, | |
6355 | * which the "break" will do. | |
6356 | */ | |
3e234289 SRV |
6357 | if (!within_module_core(rec->ip, mod) && |
6358 | !within_module_init(rec->ip, mod)) | |
b7ffffbb SRRH |
6359 | break; |
6360 | ||
6361 | cnt = 0; | |
6362 | ||
6363 | /* | |
6364 | * When adding a module, we need to check if tracers are | |
6365 | * currently enabled and if they are, and can trace this record, | |
6366 | * we need to enable the module functions as well as update the | |
6367 | * reference counts for those function records. | |
6368 | */ | |
6369 | if (ftrace_start_up) | |
6370 | cnt += referenced_filters(rec); | |
6371 | ||
6372 | /* This clears FTRACE_FL_DISABLED */ | |
6373 | rec->flags = cnt; | |
6374 | ||
6375 | if (ftrace_start_up && cnt) { | |
6376 | int failed = __ftrace_replace_code(rec, 1); | |
6377 | if (failed) { | |
6378 | ftrace_bug(failed, rec); | |
6379 | goto out_loop; | |
6380 | } | |
6381 | } | |
6382 | ||
6383 | } while_for_each_ftrace_rec(); | |
6384 | ||
6385 | out_loop: | |
6386 | if (ftrace_start_up) | |
6387 | ftrace_arch_code_modify_post_process(); | |
6388 | ||
6389 | out_unlock: | |
6390 | mutex_unlock(&ftrace_lock); | |
d7fbf8df SRV |
6391 | |
6392 | process_cached_mods(mod->name); | |
b7ffffbb SRRH |
6393 | } |
6394 | ||
b6b71f66 | 6395 | void ftrace_module_init(struct module *mod) |
90d595fe | 6396 | { |
97e9b4fc | 6397 | if (ftrace_disabled || !mod->num_ftrace_callsites) |
fed1939c | 6398 | return; |
90d595fe | 6399 | |
97e9b4fc SRRH |
6400 | ftrace_process_locs(mod, mod->ftrace_callsites, |
6401 | mod->ftrace_callsites + mod->num_ftrace_callsites); | |
8c189ea6 | 6402 | } |
aba4b5c2 SRV |
6403 | |
6404 | static void save_ftrace_mod_rec(struct ftrace_mod_map *mod_map, | |
6405 | struct dyn_ftrace *rec) | |
6406 | { | |
6407 | struct ftrace_mod_func *mod_func; | |
6408 | unsigned long symsize; | |
6409 | unsigned long offset; | |
6410 | char str[KSYM_SYMBOL_LEN]; | |
6411 | char *modname; | |
6412 | const char *ret; | |
6413 | ||
6414 | ret = kallsyms_lookup(rec->ip, &symsize, &offset, &modname, str); | |
6415 | if (!ret) | |
6416 | return; | |
6417 | ||
6418 | mod_func = kmalloc(sizeof(*mod_func), GFP_KERNEL); | |
6419 | if (!mod_func) | |
6420 | return; | |
6421 | ||
6422 | mod_func->name = kstrdup(str, GFP_KERNEL); | |
6423 | if (!mod_func->name) { | |
6424 | kfree(mod_func); | |
6425 | return; | |
6426 | } | |
6427 | ||
6428 | mod_func->ip = rec->ip - offset; | |
6429 | mod_func->size = symsize; | |
6430 | ||
6171a031 SRV |
6431 | mod_map->num_funcs++; |
6432 | ||
aba4b5c2 SRV |
6433 | list_add_rcu(&mod_func->list, &mod_map->funcs); |
6434 | } | |
6435 | ||
aba4b5c2 SRV |
6436 | static struct ftrace_mod_map * |
6437 | allocate_ftrace_mod_map(struct module *mod, | |
6438 | unsigned long start, unsigned long end) | |
6439 | { | |
6440 | struct ftrace_mod_map *mod_map; | |
6441 | ||
6442 | mod_map = kmalloc(sizeof(*mod_map), GFP_KERNEL); | |
6443 | if (!mod_map) | |
6444 | return NULL; | |
6445 | ||
6446 | mod_map->mod = mod; | |
6447 | mod_map->start_addr = start; | |
6448 | mod_map->end_addr = end; | |
6171a031 | 6449 | mod_map->num_funcs = 0; |
aba4b5c2 SRV |
6450 | |
6451 | INIT_LIST_HEAD_RCU(&mod_map->funcs); | |
6452 | ||
6453 | list_add_rcu(&mod_map->list, &ftrace_mod_maps); | |
6454 | ||
6455 | return mod_map; | |
6456 | } | |
6457 | ||
6458 | static const char * | |
6459 | ftrace_func_address_lookup(struct ftrace_mod_map *mod_map, | |
6460 | unsigned long addr, unsigned long *size, | |
6461 | unsigned long *off, char *sym) | |
6462 | { | |
6463 | struct ftrace_mod_func *found_func = NULL; | |
6464 | struct ftrace_mod_func *mod_func; | |
6465 | ||
6466 | list_for_each_entry_rcu(mod_func, &mod_map->funcs, list) { | |
6467 | if (addr >= mod_func->ip && | |
6468 | addr < mod_func->ip + mod_func->size) { | |
6469 | found_func = mod_func; | |
6470 | break; | |
6471 | } | |
6472 | } | |
6473 | ||
6474 | if (found_func) { | |
6475 | if (size) | |
6476 | *size = found_func->size; | |
6477 | if (off) | |
6478 | *off = addr - found_func->ip; | |
6479 | if (sym) | |
6480 | strlcpy(sym, found_func->name, KSYM_NAME_LEN); | |
6481 | ||
6482 | return found_func->name; | |
6483 | } | |
6484 | ||
6485 | return NULL; | |
6486 | } | |
6487 | ||
6488 | const char * | |
6489 | ftrace_mod_address_lookup(unsigned long addr, unsigned long *size, | |
6490 | unsigned long *off, char **modname, char *sym) | |
6491 | { | |
6492 | struct ftrace_mod_map *mod_map; | |
6493 | const char *ret = NULL; | |
6494 | ||
74401729 | 6495 | /* mod_map is freed via call_rcu() */ |
aba4b5c2 SRV |
6496 | preempt_disable(); |
6497 | list_for_each_entry_rcu(mod_map, &ftrace_mod_maps, list) { | |
6498 | ret = ftrace_func_address_lookup(mod_map, addr, size, off, sym); | |
6499 | if (ret) { | |
6500 | if (modname) | |
6501 | *modname = mod_map->mod->name; | |
6502 | break; | |
6503 | } | |
6504 | } | |
6505 | preempt_enable(); | |
6506 | ||
6507 | return ret; | |
6508 | } | |
6509 | ||
6171a031 SRV |
6510 | int ftrace_mod_get_kallsym(unsigned int symnum, unsigned long *value, |
6511 | char *type, char *name, | |
6512 | char *module_name, int *exported) | |
6513 | { | |
6514 | struct ftrace_mod_map *mod_map; | |
6515 | struct ftrace_mod_func *mod_func; | |
6516 | ||
6517 | preempt_disable(); | |
6518 | list_for_each_entry_rcu(mod_map, &ftrace_mod_maps, list) { | |
6519 | ||
6520 | if (symnum >= mod_map->num_funcs) { | |
6521 | symnum -= mod_map->num_funcs; | |
6522 | continue; | |
6523 | } | |
6524 | ||
6525 | list_for_each_entry_rcu(mod_func, &mod_map->funcs, list) { | |
6526 | if (symnum > 1) { | |
6527 | symnum--; | |
6528 | continue; | |
6529 | } | |
6530 | ||
6531 | *value = mod_func->ip; | |
6532 | *type = 'T'; | |
6533 | strlcpy(name, mod_func->name, KSYM_NAME_LEN); | |
6534 | strlcpy(module_name, mod_map->mod->name, MODULE_NAME_LEN); | |
6535 | *exported = 1; | |
6536 | preempt_enable(); | |
6537 | return 0; | |
6538 | } | |
6539 | WARN_ON(1); | |
6540 | break; | |
6541 | } | |
6542 | preempt_enable(); | |
6543 | return -ERANGE; | |
6544 | } | |
6545 | ||
aba4b5c2 SRV |
6546 | #else |
6547 | static void save_ftrace_mod_rec(struct ftrace_mod_map *mod_map, | |
6548 | struct dyn_ftrace *rec) { } | |
6549 | static inline struct ftrace_mod_map * | |
6550 | allocate_ftrace_mod_map(struct module *mod, | |
6551 | unsigned long start, unsigned long end) | |
6552 | { | |
6553 | return NULL; | |
6554 | } | |
93eb677d SR |
6555 | #endif /* CONFIG_MODULES */ |
6556 | ||
8715b108 JF |
6557 | struct ftrace_init_func { |
6558 | struct list_head list; | |
6559 | unsigned long ip; | |
6560 | }; | |
6561 | ||
6562 | /* Clear any init ips from hashes */ | |
6563 | static void | |
6564 | clear_func_from_hash(struct ftrace_init_func *func, struct ftrace_hash *hash) | |
42c269c8 | 6565 | { |
8715b108 JF |
6566 | struct ftrace_func_entry *entry; |
6567 | ||
08468754 | 6568 | entry = ftrace_lookup_ip(hash, func->ip); |
8715b108 JF |
6569 | /* |
6570 | * Do not allow this rec to match again. | |
6571 | * Yeah, it may waste some memory, but will be removed | |
6572 | * if/when the hash is modified again. | |
6573 | */ | |
6574 | if (entry) | |
6575 | entry->ip = 0; | |
6576 | } | |
6577 | ||
6578 | static void | |
6579 | clear_func_from_hashes(struct ftrace_init_func *func) | |
6580 | { | |
6581 | struct trace_array *tr; | |
6582 | ||
6583 | mutex_lock(&trace_types_lock); | |
6584 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6585 | if (!tr->ops || !tr->ops->func_hash) | |
6586 | continue; | |
6587 | mutex_lock(&tr->ops->func_hash->regex_lock); | |
6588 | clear_func_from_hash(func, tr->ops->func_hash->filter_hash); | |
6589 | clear_func_from_hash(func, tr->ops->func_hash->notrace_hash); | |
6590 | mutex_unlock(&tr->ops->func_hash->regex_lock); | |
6591 | } | |
6592 | mutex_unlock(&trace_types_lock); | |
6593 | } | |
6594 | ||
6595 | static void add_to_clear_hash_list(struct list_head *clear_list, | |
6596 | struct dyn_ftrace *rec) | |
6597 | { | |
6598 | struct ftrace_init_func *func; | |
6599 | ||
6600 | func = kmalloc(sizeof(*func), GFP_KERNEL); | |
6601 | if (!func) { | |
24589e3a | 6602 | MEM_FAIL(1, "alloc failure, ftrace filter could be stale\n"); |
8715b108 JF |
6603 | return; |
6604 | } | |
6605 | ||
6606 | func->ip = rec->ip; | |
6607 | list_add(&func->list, clear_list); | |
6608 | } | |
6609 | ||
aba4b5c2 | 6610 | void ftrace_free_mem(struct module *mod, void *start_ptr, void *end_ptr) |
42c269c8 | 6611 | { |
6cafbe15 SRV |
6612 | unsigned long start = (unsigned long)(start_ptr); |
6613 | unsigned long end = (unsigned long)(end_ptr); | |
42c269c8 SRV |
6614 | struct ftrace_page **last_pg = &ftrace_pages_start; |
6615 | struct ftrace_page *pg; | |
6616 | struct dyn_ftrace *rec; | |
6617 | struct dyn_ftrace key; | |
aba4b5c2 | 6618 | struct ftrace_mod_map *mod_map = NULL; |
8715b108 JF |
6619 | struct ftrace_init_func *func, *func_next; |
6620 | struct list_head clear_hash; | |
42c269c8 SRV |
6621 | int order; |
6622 | ||
8715b108 JF |
6623 | INIT_LIST_HEAD(&clear_hash); |
6624 | ||
42c269c8 SRV |
6625 | key.ip = start; |
6626 | key.flags = end; /* overload flags, as it is unsigned long */ | |
6627 | ||
6628 | mutex_lock(&ftrace_lock); | |
6629 | ||
aba4b5c2 SRV |
6630 | /* |
6631 | * If we are freeing module init memory, then check if | |
6632 | * any tracer is active. If so, we need to save a mapping of | |
6633 | * the module functions being freed with the address. | |
6634 | */ | |
6635 | if (mod && ftrace_ops_list != &ftrace_list_end) | |
6636 | mod_map = allocate_ftrace_mod_map(mod, start, end); | |
6637 | ||
42c269c8 SRV |
6638 | for (pg = ftrace_pages_start; pg; last_pg = &pg->next, pg = *last_pg) { |
6639 | if (end < pg->records[0].ip || | |
6640 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) | |
6641 | continue; | |
6642 | again: | |
6643 | rec = bsearch(&key, pg->records, pg->index, | |
6644 | sizeof(struct dyn_ftrace), | |
6645 | ftrace_cmp_recs); | |
6646 | if (!rec) | |
6647 | continue; | |
aba4b5c2 | 6648 | |
8715b108 JF |
6649 | /* rec will be cleared from hashes after ftrace_lock unlock */ |
6650 | add_to_clear_hash_list(&clear_hash, rec); | |
6651 | ||
aba4b5c2 SRV |
6652 | if (mod_map) |
6653 | save_ftrace_mod_rec(mod_map, rec); | |
6654 | ||
42c269c8 | 6655 | pg->index--; |
4ec78467 | 6656 | ftrace_update_tot_cnt--; |
42c269c8 SRV |
6657 | if (!pg->index) { |
6658 | *last_pg = pg->next; | |
6659 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); | |
6660 | free_pages((unsigned long)pg->records, order); | |
da537f0a SRV |
6661 | ftrace_number_of_pages -= 1 << order; |
6662 | ftrace_number_of_groups--; | |
42c269c8 SRV |
6663 | kfree(pg); |
6664 | pg = container_of(last_pg, struct ftrace_page, next); | |
6665 | if (!(*last_pg)) | |
6666 | ftrace_pages = pg; | |
6667 | continue; | |
6668 | } | |
6669 | memmove(rec, rec + 1, | |
6670 | (pg->index - (rec - pg->records)) * sizeof(*rec)); | |
6671 | /* More than one function may be in this block */ | |
6672 | goto again; | |
6673 | } | |
6674 | mutex_unlock(&ftrace_lock); | |
8715b108 JF |
6675 | |
6676 | list_for_each_entry_safe(func, func_next, &clear_hash, list) { | |
6677 | clear_func_from_hashes(func); | |
6678 | kfree(func); | |
6679 | } | |
42c269c8 SRV |
6680 | } |
6681 | ||
6cafbe15 SRV |
6682 | void __init ftrace_free_init_mem(void) |
6683 | { | |
6684 | void *start = (void *)(&__init_begin); | |
6685 | void *end = (void *)(&__init_end); | |
6686 | ||
aba4b5c2 | 6687 | ftrace_free_mem(NULL, start, end); |
42c269c8 SRV |
6688 | } |
6689 | ||
68bf21aa SR |
6690 | void __init ftrace_init(void) |
6691 | { | |
1dc43cf0 JS |
6692 | extern unsigned long __start_mcount_loc[]; |
6693 | extern unsigned long __stop_mcount_loc[]; | |
3a36cb11 | 6694 | unsigned long count, flags; |
68bf21aa SR |
6695 | int ret; |
6696 | ||
68bf21aa | 6697 | local_irq_save(flags); |
3a36cb11 | 6698 | ret = ftrace_dyn_arch_init(); |
68bf21aa | 6699 | local_irq_restore(flags); |
af64a7cb | 6700 | if (ret) |
68bf21aa SR |
6701 | goto failed; |
6702 | ||
6703 | count = __stop_mcount_loc - __start_mcount_loc; | |
c867ccd8 JS |
6704 | if (!count) { |
6705 | pr_info("ftrace: No functions to be traced?\n"); | |
68bf21aa | 6706 | goto failed; |
c867ccd8 JS |
6707 | } |
6708 | ||
6709 | pr_info("ftrace: allocating %ld entries in %ld pages\n", | |
6710 | count, count / ENTRIES_PER_PAGE + 1); | |
68bf21aa SR |
6711 | |
6712 | last_ftrace_enabled = ftrace_enabled = 1; | |
6713 | ||
5cb084bb | 6714 | ret = ftrace_process_locs(NULL, |
31e88909 | 6715 | __start_mcount_loc, |
68bf21aa SR |
6716 | __stop_mcount_loc); |
6717 | ||
da537f0a SRV |
6718 | pr_info("ftrace: allocated %ld pages with %ld groups\n", |
6719 | ftrace_number_of_pages, ftrace_number_of_groups); | |
6720 | ||
2af15d6a SR |
6721 | set_ftrace_early_filters(); |
6722 | ||
68bf21aa SR |
6723 | return; |
6724 | failed: | |
6725 | ftrace_disabled = 1; | |
6726 | } | |
68bf21aa | 6727 | |
f3bea491 SRRH |
6728 | /* Do nothing if arch does not support this */ |
6729 | void __weak arch_ftrace_update_trampoline(struct ftrace_ops *ops) | |
6730 | { | |
6731 | } | |
6732 | ||
6733 | static void ftrace_update_trampoline(struct ftrace_ops *ops) | |
6734 | { | |
f3bea491 SRRH |
6735 | arch_ftrace_update_trampoline(ops); |
6736 | } | |
6737 | ||
04ec7bb6 SRV |
6738 | void ftrace_init_trace_array(struct trace_array *tr) |
6739 | { | |
6740 | INIT_LIST_HEAD(&tr->func_probes); | |
673feb9d SRV |
6741 | INIT_LIST_HEAD(&tr->mod_trace); |
6742 | INIT_LIST_HEAD(&tr->mod_notrace); | |
04ec7bb6 | 6743 | } |
3d083395 | 6744 | #else |
0b6e4d56 | 6745 | |
3306fc4a | 6746 | struct ftrace_ops global_ops = { |
bd69c30b | 6747 | .func = ftrace_stub, |
e3eea140 SRRH |
6748 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | |
6749 | FTRACE_OPS_FL_INITIALIZED | | |
6750 | FTRACE_OPS_FL_PID, | |
bd69c30b SR |
6751 | }; |
6752 | ||
0b6e4d56 FW |
6753 | static int __init ftrace_nodyn_init(void) |
6754 | { | |
6755 | ftrace_enabled = 1; | |
6756 | return 0; | |
6757 | } | |
6f415672 | 6758 | core_initcall(ftrace_nodyn_init); |
0b6e4d56 | 6759 | |
8434dc93 | 6760 | static inline int ftrace_init_dyn_tracefs(struct dentry *d_tracer) { return 0; } |
df4fc315 | 6761 | static inline void ftrace_startup_enable(int command) { } |
e1effa01 | 6762 | static inline void ftrace_startup_all(int command) { } |
8a56d776 | 6763 | |
c7aafc54 IM |
6764 | # define ftrace_startup_sysctl() do { } while (0) |
6765 | # define ftrace_shutdown_sysctl() do { } while (0) | |
b848914c | 6766 | |
f3bea491 SRRH |
6767 | static void ftrace_update_trampoline(struct ftrace_ops *ops) |
6768 | { | |
6769 | } | |
6770 | ||
3d083395 SR |
6771 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
6772 | ||
4104d326 SRRH |
6773 | __init void ftrace_init_global_array_ops(struct trace_array *tr) |
6774 | { | |
6775 | tr->ops = &global_ops; | |
6776 | tr->ops->private = tr; | |
04ec7bb6 | 6777 | ftrace_init_trace_array(tr); |
4104d326 SRRH |
6778 | } |
6779 | ||
6780 | void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func) | |
6781 | { | |
6782 | /* If we filter on pids, update to use the pid function */ | |
6783 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { | |
6784 | if (WARN_ON(tr->ops->func != ftrace_stub)) | |
6785 | printk("ftrace ops had %pS for function\n", | |
6786 | tr->ops->func); | |
4104d326 SRRH |
6787 | } |
6788 | tr->ops->func = func; | |
6789 | tr->ops->private = tr; | |
6790 | } | |
6791 | ||
6792 | void ftrace_reset_array_ops(struct trace_array *tr) | |
6793 | { | |
6794 | tr->ops->func = ftrace_stub; | |
6795 | } | |
6796 | ||
fabe38ab | 6797 | static nokprobe_inline void |
2f5f6ad9 | 6798 | __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 6799 | struct ftrace_ops *ignored, struct pt_regs *regs) |
b848914c | 6800 | { |
cdbe61bf | 6801 | struct ftrace_ops *op; |
edc15caf | 6802 | int bit; |
b848914c | 6803 | |
edc15caf SR |
6804 | bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); |
6805 | if (bit < 0) | |
6806 | return; | |
b1cff0ad | 6807 | |
cdbe61bf SR |
6808 | /* |
6809 | * Some of the ops may be dynamically allocated, | |
74401729 | 6810 | * they must be freed after a synchronize_rcu(). |
cdbe61bf SR |
6811 | */ |
6812 | preempt_disable_notrace(); | |
ba27f2bc | 6813 | |
0a016409 | 6814 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
2fa717a0 SRV |
6815 | /* Stub functions don't need to be called nor tested */ |
6816 | if (op->flags & FTRACE_OPS_FL_STUB) | |
6817 | continue; | |
ba27f2bc SRRH |
6818 | /* |
6819 | * Check the following for each ops before calling their func: | |
6820 | * if RCU flag is set, then rcu_is_watching() must be true | |
6821 | * if PER_CPU is set, then ftrace_function_local_disable() | |
6822 | * must be false | |
6823 | * Otherwise test if the ip matches the ops filter | |
6824 | * | |
6825 | * If any of the above fails then the op->func() is not executed. | |
6826 | */ | |
6827 | if ((!(op->flags & FTRACE_OPS_FL_RCU) || rcu_is_watching()) && | |
ba27f2bc | 6828 | ftrace_ops_test(op, ip, regs)) { |
1d48d596 SRRH |
6829 | if (FTRACE_WARN_ON(!op->func)) { |
6830 | pr_warn("op=%p %pS\n", op, op); | |
4104d326 SRRH |
6831 | goto out; |
6832 | } | |
a1e2e31d | 6833 | op->func(ip, parent_ip, op, regs); |
4104d326 | 6834 | } |
0a016409 | 6835 | } while_for_each_ftrace_op(op); |
4104d326 | 6836 | out: |
cdbe61bf | 6837 | preempt_enable_notrace(); |
edc15caf | 6838 | trace_clear_recursion(bit); |
b848914c SR |
6839 | } |
6840 | ||
2f5f6ad9 SR |
6841 | /* |
6842 | * Some archs only support passing ip and parent_ip. Even though | |
6843 | * the list function ignores the op parameter, we do not want any | |
6844 | * C side effects, where a function is called without the caller | |
6845 | * sending a third parameter. | |
a1e2e31d SR |
6846 | * Archs are to support both the regs and ftrace_ops at the same time. |
6847 | * If they support ftrace_ops, it is assumed they support regs. | |
6848 | * If call backs want to use regs, they must either check for regs | |
06aeaaea MH |
6849 | * being NULL, or CONFIG_DYNAMIC_FTRACE_WITH_REGS. |
6850 | * Note, CONFIG_DYNAMIC_FTRACE_WITH_REGS expects a full regs to be saved. | |
a1e2e31d | 6851 | * An architecture can pass partial regs with ftrace_ops and still |
b8ec330a | 6852 | * set the ARCH_SUPPORTS_FTRACE_OPS. |
2f5f6ad9 SR |
6853 | */ |
6854 | #if ARCH_SUPPORTS_FTRACE_OPS | |
6855 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 6856 | struct ftrace_ops *op, struct pt_regs *regs) |
2f5f6ad9 | 6857 | { |
a1e2e31d | 6858 | __ftrace_ops_list_func(ip, parent_ip, NULL, regs); |
2f5f6ad9 | 6859 | } |
fabe38ab | 6860 | NOKPROBE_SYMBOL(ftrace_ops_list_func); |
2f5f6ad9 SR |
6861 | #else |
6862 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip) | |
6863 | { | |
a1e2e31d | 6864 | __ftrace_ops_list_func(ip, parent_ip, NULL, NULL); |
2f5f6ad9 | 6865 | } |
fabe38ab | 6866 | NOKPROBE_SYMBOL(ftrace_ops_no_ops); |
2f5f6ad9 SR |
6867 | #endif |
6868 | ||
f1ff6348 SRRH |
6869 | /* |
6870 | * If there's only one function registered but it does not support | |
c68c0fa2 SRRH |
6871 | * recursion, needs RCU protection and/or requires per cpu handling, then |
6872 | * this function will be called by the mcount trampoline. | |
f1ff6348 | 6873 | */ |
c68c0fa2 | 6874 | static void ftrace_ops_assist_func(unsigned long ip, unsigned long parent_ip, |
f1ff6348 SRRH |
6875 | struct ftrace_ops *op, struct pt_regs *regs) |
6876 | { | |
6877 | int bit; | |
6878 | ||
c68c0fa2 SRRH |
6879 | if ((op->flags & FTRACE_OPS_FL_RCU) && !rcu_is_watching()) |
6880 | return; | |
6881 | ||
f1ff6348 SRRH |
6882 | bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); |
6883 | if (bit < 0) | |
6884 | return; | |
6885 | ||
c68c0fa2 | 6886 | preempt_disable_notrace(); |
f1ff6348 | 6887 | |
b3a88803 | 6888 | op->func(ip, parent_ip, op, regs); |
c68c0fa2 SRRH |
6889 | |
6890 | preempt_enable_notrace(); | |
f1ff6348 SRRH |
6891 | trace_clear_recursion(bit); |
6892 | } | |
fabe38ab | 6893 | NOKPROBE_SYMBOL(ftrace_ops_assist_func); |
f1ff6348 | 6894 | |
87354059 SRRH |
6895 | /** |
6896 | * ftrace_ops_get_func - get the function a trampoline should call | |
6897 | * @ops: the ops to get the function for | |
6898 | * | |
6899 | * Normally the mcount trampoline will call the ops->func, but there | |
6900 | * are times that it should not. For example, if the ops does not | |
6901 | * have its own recursion protection, then it should call the | |
3a150df9 | 6902 | * ftrace_ops_assist_func() instead. |
87354059 SRRH |
6903 | * |
6904 | * Returns the function that the trampoline should call for @ops. | |
6905 | */ | |
6906 | ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops) | |
6907 | { | |
87354059 | 6908 | /* |
c68c0fa2 SRRH |
6909 | * If the function does not handle recursion, needs to be RCU safe, |
6910 | * or does per cpu logic, then we need to call the assist handler. | |
87354059 | 6911 | */ |
c68c0fa2 | 6912 | if (!(ops->flags & FTRACE_OPS_FL_RECURSION_SAFE) || |
b3a88803 | 6913 | ops->flags & FTRACE_OPS_FL_RCU) |
c68c0fa2 | 6914 | return ftrace_ops_assist_func; |
87354059 SRRH |
6915 | |
6916 | return ops->func; | |
6917 | } | |
6918 | ||
345ddcc8 SRRH |
6919 | static void |
6920 | ftrace_filter_pid_sched_switch_probe(void *data, bool preempt, | |
6921 | struct task_struct *prev, struct task_struct *next) | |
978f3a45 | 6922 | { |
345ddcc8 SRRH |
6923 | struct trace_array *tr = data; |
6924 | struct trace_pid_list *pid_list; | |
b3b1e6ed | 6925 | struct trace_pid_list *no_pid_list; |
978f3a45 | 6926 | |
345ddcc8 | 6927 | pid_list = rcu_dereference_sched(tr->function_pids); |
b3b1e6ed | 6928 | no_pid_list = rcu_dereference_sched(tr->function_no_pids); |
e32d8956 | 6929 | |
b3b1e6ed | 6930 | if (trace_ignore_this_task(pid_list, no_pid_list, next)) |
717e3f5e SRV |
6931 | this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid, |
6932 | FTRACE_PID_IGNORE); | |
6933 | else | |
6934 | this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid, | |
6935 | next->pid); | |
978f3a45 SR |
6936 | } |
6937 | ||
1e10486f NK |
6938 | static void |
6939 | ftrace_pid_follow_sched_process_fork(void *data, | |
6940 | struct task_struct *self, | |
6941 | struct task_struct *task) | |
6942 | { | |
6943 | struct trace_pid_list *pid_list; | |
6944 | struct trace_array *tr = data; | |
6945 | ||
6946 | pid_list = rcu_dereference_sched(tr->function_pids); | |
6947 | trace_filter_add_remove_task(pid_list, self, task); | |
b3b1e6ed SRV |
6948 | |
6949 | pid_list = rcu_dereference_sched(tr->function_no_pids); | |
6950 | trace_filter_add_remove_task(pid_list, self, task); | |
1e10486f NK |
6951 | } |
6952 | ||
6953 | static void | |
6954 | ftrace_pid_follow_sched_process_exit(void *data, struct task_struct *task) | |
6955 | { | |
6956 | struct trace_pid_list *pid_list; | |
6957 | struct trace_array *tr = data; | |
6958 | ||
6959 | pid_list = rcu_dereference_sched(tr->function_pids); | |
6960 | trace_filter_add_remove_task(pid_list, NULL, task); | |
b3b1e6ed SRV |
6961 | |
6962 | pid_list = rcu_dereference_sched(tr->function_no_pids); | |
6963 | trace_filter_add_remove_task(pid_list, NULL, task); | |
1e10486f NK |
6964 | } |
6965 | ||
6966 | void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) | |
6967 | { | |
6968 | if (enable) { | |
6969 | register_trace_sched_process_fork(ftrace_pid_follow_sched_process_fork, | |
6970 | tr); | |
6971 | register_trace_sched_process_exit(ftrace_pid_follow_sched_process_exit, | |
6972 | tr); | |
6973 | } else { | |
6974 | unregister_trace_sched_process_fork(ftrace_pid_follow_sched_process_fork, | |
6975 | tr); | |
6976 | unregister_trace_sched_process_exit(ftrace_pid_follow_sched_process_exit, | |
6977 | tr); | |
6978 | } | |
6979 | } | |
6980 | ||
b3b1e6ed | 6981 | static void clear_ftrace_pids(struct trace_array *tr, int type) |
e32d8956 | 6982 | { |
345ddcc8 | 6983 | struct trace_pid_list *pid_list; |
b3b1e6ed | 6984 | struct trace_pid_list *no_pid_list; |
345ddcc8 | 6985 | int cpu; |
e32d8956 | 6986 | |
345ddcc8 SRRH |
6987 | pid_list = rcu_dereference_protected(tr->function_pids, |
6988 | lockdep_is_held(&ftrace_lock)); | |
b3b1e6ed SRV |
6989 | no_pid_list = rcu_dereference_protected(tr->function_no_pids, |
6990 | lockdep_is_held(&ftrace_lock)); | |
6991 | ||
6992 | /* Make sure there's something to do */ | |
27683626 | 6993 | if (!pid_type_enabled(type, pid_list, no_pid_list)) |
345ddcc8 | 6994 | return; |
229c4ef8 | 6995 | |
b3b1e6ed | 6996 | /* See if the pids still need to be checked after this */ |
27683626 | 6997 | if (!still_need_pid_events(type, pid_list, no_pid_list)) { |
b3b1e6ed SRV |
6998 | unregister_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr); |
6999 | for_each_possible_cpu(cpu) | |
7000 | per_cpu_ptr(tr->array_buffer.data, cpu)->ftrace_ignore_pid = FTRACE_PID_TRACE; | |
7001 | } | |
e32d8956 | 7002 | |
b3b1e6ed SRV |
7003 | if (type & TRACE_PIDS) |
7004 | rcu_assign_pointer(tr->function_pids, NULL); | |
978f3a45 | 7005 | |
b3b1e6ed SRV |
7006 | if (type & TRACE_NO_PIDS) |
7007 | rcu_assign_pointer(tr->function_no_pids, NULL); | |
978f3a45 | 7008 | |
345ddcc8 | 7009 | /* Wait till all users are no longer using pid filtering */ |
74401729 | 7010 | synchronize_rcu(); |
e32d8956 | 7011 | |
b3b1e6ed SRV |
7012 | if ((type & TRACE_PIDS) && pid_list) |
7013 | trace_free_pid_list(pid_list); | |
7014 | ||
7015 | if ((type & TRACE_NO_PIDS) && no_pid_list) | |
7016 | trace_free_pid_list(no_pid_list); | |
e32d8956 SR |
7017 | } |
7018 | ||
d879d0b8 NK |
7019 | void ftrace_clear_pids(struct trace_array *tr) |
7020 | { | |
7021 | mutex_lock(&ftrace_lock); | |
7022 | ||
b3b1e6ed | 7023 | clear_ftrace_pids(tr, TRACE_PIDS | TRACE_NO_PIDS); |
d879d0b8 NK |
7024 | |
7025 | mutex_unlock(&ftrace_lock); | |
7026 | } | |
7027 | ||
b3b1e6ed | 7028 | static void ftrace_pid_reset(struct trace_array *tr, int type) |
df4fc315 | 7029 | { |
756d17ee | 7030 | mutex_lock(&ftrace_lock); |
b3b1e6ed | 7031 | clear_ftrace_pids(tr, type); |
978f3a45 | 7032 | |
756d17ee | 7033 | ftrace_update_pid_func(); |
e1effa01 | 7034 | ftrace_startup_all(0); |
756d17ee | 7035 | |
7036 | mutex_unlock(&ftrace_lock); | |
756d17ee | 7037 | } |
7038 | ||
345ddcc8 SRRH |
7039 | /* Greater than any max PID */ |
7040 | #define FTRACE_NO_PIDS (void *)(PID_MAX_LIMIT + 1) | |
df4fc315 | 7041 | |
756d17ee | 7042 | static void *fpid_start(struct seq_file *m, loff_t *pos) |
345ddcc8 | 7043 | __acquires(RCU) |
756d17ee | 7044 | { |
345ddcc8 SRRH |
7045 | struct trace_pid_list *pid_list; |
7046 | struct trace_array *tr = m->private; | |
7047 | ||
756d17ee | 7048 | mutex_lock(&ftrace_lock); |
345ddcc8 SRRH |
7049 | rcu_read_lock_sched(); |
7050 | ||
7051 | pid_list = rcu_dereference_sched(tr->function_pids); | |
756d17ee | 7052 | |
345ddcc8 SRRH |
7053 | if (!pid_list) |
7054 | return !(*pos) ? FTRACE_NO_PIDS : NULL; | |
756d17ee | 7055 | |
345ddcc8 | 7056 | return trace_pid_start(pid_list, pos); |
756d17ee | 7057 | } |
7058 | ||
7059 | static void *fpid_next(struct seq_file *m, void *v, loff_t *pos) | |
7060 | { | |
345ddcc8 SRRH |
7061 | struct trace_array *tr = m->private; |
7062 | struct trace_pid_list *pid_list = rcu_dereference_sched(tr->function_pids); | |
7063 | ||
e4075e8b VA |
7064 | if (v == FTRACE_NO_PIDS) { |
7065 | (*pos)++; | |
756d17ee | 7066 | return NULL; |
e4075e8b | 7067 | } |
345ddcc8 | 7068 | return trace_pid_next(pid_list, v, pos); |
756d17ee | 7069 | } |
7070 | ||
7071 | static void fpid_stop(struct seq_file *m, void *p) | |
345ddcc8 | 7072 | __releases(RCU) |
756d17ee | 7073 | { |
345ddcc8 | 7074 | rcu_read_unlock_sched(); |
756d17ee | 7075 | mutex_unlock(&ftrace_lock); |
7076 | } | |
7077 | ||
7078 | static int fpid_show(struct seq_file *m, void *v) | |
7079 | { | |
345ddcc8 | 7080 | if (v == FTRACE_NO_PIDS) { |
fa6f0cc7 | 7081 | seq_puts(m, "no pid\n"); |
756d17ee | 7082 | return 0; |
7083 | } | |
7084 | ||
345ddcc8 | 7085 | return trace_pid_show(m, v); |
756d17ee | 7086 | } |
7087 | ||
7088 | static const struct seq_operations ftrace_pid_sops = { | |
7089 | .start = fpid_start, | |
7090 | .next = fpid_next, | |
7091 | .stop = fpid_stop, | |
7092 | .show = fpid_show, | |
7093 | }; | |
7094 | ||
b3b1e6ed SRV |
7095 | static void *fnpid_start(struct seq_file *m, loff_t *pos) |
7096 | __acquires(RCU) | |
7097 | { | |
7098 | struct trace_pid_list *pid_list; | |
7099 | struct trace_array *tr = m->private; | |
7100 | ||
7101 | mutex_lock(&ftrace_lock); | |
7102 | rcu_read_lock_sched(); | |
7103 | ||
7104 | pid_list = rcu_dereference_sched(tr->function_no_pids); | |
7105 | ||
7106 | if (!pid_list) | |
7107 | return !(*pos) ? FTRACE_NO_PIDS : NULL; | |
7108 | ||
7109 | return trace_pid_start(pid_list, pos); | |
7110 | } | |
7111 | ||
7112 | static void *fnpid_next(struct seq_file *m, void *v, loff_t *pos) | |
756d17ee | 7113 | { |
b3b1e6ed SRV |
7114 | struct trace_array *tr = m->private; |
7115 | struct trace_pid_list *pid_list = rcu_dereference_sched(tr->function_no_pids); | |
7116 | ||
7117 | if (v == FTRACE_NO_PIDS) { | |
7118 | (*pos)++; | |
7119 | return NULL; | |
7120 | } | |
7121 | return trace_pid_next(pid_list, v, pos); | |
7122 | } | |
7123 | ||
7124 | static const struct seq_operations ftrace_no_pid_sops = { | |
7125 | .start = fnpid_start, | |
7126 | .next = fnpid_next, | |
7127 | .stop = fpid_stop, | |
7128 | .show = fpid_show, | |
7129 | }; | |
7130 | ||
7131 | static int pid_open(struct inode *inode, struct file *file, int type) | |
7132 | { | |
7133 | const struct seq_operations *seq_ops; | |
345ddcc8 SRRH |
7134 | struct trace_array *tr = inode->i_private; |
7135 | struct seq_file *m; | |
756d17ee | 7136 | int ret = 0; |
7137 | ||
8530dec6 SRV |
7138 | ret = tracing_check_open_get_tr(tr); |
7139 | if (ret) | |
7140 | return ret; | |
345ddcc8 | 7141 | |
756d17ee | 7142 | if ((file->f_mode & FMODE_WRITE) && |
7143 | (file->f_flags & O_TRUNC)) | |
b3b1e6ed SRV |
7144 | ftrace_pid_reset(tr, type); |
7145 | ||
7146 | switch (type) { | |
7147 | case TRACE_PIDS: | |
7148 | seq_ops = &ftrace_pid_sops; | |
7149 | break; | |
7150 | case TRACE_NO_PIDS: | |
7151 | seq_ops = &ftrace_no_pid_sops; | |
7152 | break; | |
7153 | } | |
756d17ee | 7154 | |
b3b1e6ed | 7155 | ret = seq_open(file, seq_ops); |
345ddcc8 SRRH |
7156 | if (ret < 0) { |
7157 | trace_array_put(tr); | |
7158 | } else { | |
7159 | m = file->private_data; | |
7160 | /* copy tr over to seq ops */ | |
7161 | m->private = tr; | |
7162 | } | |
756d17ee | 7163 | |
7164 | return ret; | |
7165 | } | |
7166 | ||
b3b1e6ed SRV |
7167 | static int |
7168 | ftrace_pid_open(struct inode *inode, struct file *file) | |
7169 | { | |
7170 | return pid_open(inode, file, TRACE_PIDS); | |
7171 | } | |
7172 | ||
7173 | static int | |
7174 | ftrace_no_pid_open(struct inode *inode, struct file *file) | |
7175 | { | |
7176 | return pid_open(inode, file, TRACE_NO_PIDS); | |
7177 | } | |
7178 | ||
345ddcc8 SRRH |
7179 | static void ignore_task_cpu(void *data) |
7180 | { | |
7181 | struct trace_array *tr = data; | |
7182 | struct trace_pid_list *pid_list; | |
b3b1e6ed | 7183 | struct trace_pid_list *no_pid_list; |
345ddcc8 SRRH |
7184 | |
7185 | /* | |
7186 | * This function is called by on_each_cpu() while the | |
7187 | * event_mutex is held. | |
7188 | */ | |
7189 | pid_list = rcu_dereference_protected(tr->function_pids, | |
7190 | mutex_is_locked(&ftrace_lock)); | |
b3b1e6ed SRV |
7191 | no_pid_list = rcu_dereference_protected(tr->function_no_pids, |
7192 | mutex_is_locked(&ftrace_lock)); | |
345ddcc8 | 7193 | |
b3b1e6ed | 7194 | if (trace_ignore_this_task(pid_list, no_pid_list, current)) |
717e3f5e SRV |
7195 | this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid, |
7196 | FTRACE_PID_IGNORE); | |
7197 | else | |
7198 | this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid, | |
7199 | current->pid); | |
345ddcc8 SRRH |
7200 | } |
7201 | ||
df4fc315 | 7202 | static ssize_t |
b3b1e6ed SRV |
7203 | pid_write(struct file *filp, const char __user *ubuf, |
7204 | size_t cnt, loff_t *ppos, int type) | |
df4fc315 | 7205 | { |
345ddcc8 SRRH |
7206 | struct seq_file *m = filp->private_data; |
7207 | struct trace_array *tr = m->private; | |
b3b1e6ed SRV |
7208 | struct trace_pid_list *filtered_pids; |
7209 | struct trace_pid_list *other_pids; | |
345ddcc8 SRRH |
7210 | struct trace_pid_list *pid_list; |
7211 | ssize_t ret; | |
df4fc315 | 7212 | |
345ddcc8 SRRH |
7213 | if (!cnt) |
7214 | return 0; | |
7215 | ||
7216 | mutex_lock(&ftrace_lock); | |
7217 | ||
b3b1e6ed SRV |
7218 | switch (type) { |
7219 | case TRACE_PIDS: | |
7220 | filtered_pids = rcu_dereference_protected(tr->function_pids, | |
345ddcc8 | 7221 | lockdep_is_held(&ftrace_lock)); |
b3b1e6ed SRV |
7222 | other_pids = rcu_dereference_protected(tr->function_no_pids, |
7223 | lockdep_is_held(&ftrace_lock)); | |
7224 | break; | |
7225 | case TRACE_NO_PIDS: | |
7226 | filtered_pids = rcu_dereference_protected(tr->function_no_pids, | |
7227 | lockdep_is_held(&ftrace_lock)); | |
7228 | other_pids = rcu_dereference_protected(tr->function_pids, | |
345ddcc8 | 7229 | lockdep_is_held(&ftrace_lock)); |
b3b1e6ed SRV |
7230 | break; |
7231 | } | |
345ddcc8 SRRH |
7232 | |
7233 | ret = trace_pid_write(filtered_pids, &pid_list, ubuf, cnt); | |
7234 | if (ret < 0) | |
7235 | goto out; | |
df4fc315 | 7236 | |
b3b1e6ed SRV |
7237 | switch (type) { |
7238 | case TRACE_PIDS: | |
7239 | rcu_assign_pointer(tr->function_pids, pid_list); | |
7240 | break; | |
7241 | case TRACE_NO_PIDS: | |
7242 | rcu_assign_pointer(tr->function_no_pids, pid_list); | |
7243 | break; | |
7244 | } | |
7245 | ||
df4fc315 | 7246 | |
345ddcc8 | 7247 | if (filtered_pids) { |
74401729 | 7248 | synchronize_rcu(); |
345ddcc8 | 7249 | trace_free_pid_list(filtered_pids); |
b3b1e6ed | 7250 | } else if (pid_list && !other_pids) { |
345ddcc8 SRRH |
7251 | /* Register a probe to set whether to ignore the tracing of a task */ |
7252 | register_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr); | |
7253 | } | |
df4fc315 | 7254 | |
756d17ee | 7255 | /* |
345ddcc8 SRRH |
7256 | * Ignoring of pids is done at task switch. But we have to |
7257 | * check for those tasks that are currently running. | |
7258 | * Always do this in case a pid was appended or removed. | |
756d17ee | 7259 | */ |
345ddcc8 | 7260 | on_each_cpu(ignore_task_cpu, tr, 1); |
756d17ee | 7261 | |
345ddcc8 SRRH |
7262 | ftrace_update_pid_func(); |
7263 | ftrace_startup_all(0); | |
7264 | out: | |
7265 | mutex_unlock(&ftrace_lock); | |
df4fc315 | 7266 | |
345ddcc8 SRRH |
7267 | if (ret > 0) |
7268 | *ppos += ret; | |
df4fc315 | 7269 | |
345ddcc8 | 7270 | return ret; |
756d17ee | 7271 | } |
df4fc315 | 7272 | |
b3b1e6ed SRV |
7273 | static ssize_t |
7274 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
7275 | size_t cnt, loff_t *ppos) | |
7276 | { | |
7277 | return pid_write(filp, ubuf, cnt, ppos, TRACE_PIDS); | |
7278 | } | |
7279 | ||
7280 | static ssize_t | |
7281 | ftrace_no_pid_write(struct file *filp, const char __user *ubuf, | |
7282 | size_t cnt, loff_t *ppos) | |
7283 | { | |
7284 | return pid_write(filp, ubuf, cnt, ppos, TRACE_NO_PIDS); | |
7285 | } | |
7286 | ||
756d17ee | 7287 | static int |
7288 | ftrace_pid_release(struct inode *inode, struct file *file) | |
7289 | { | |
345ddcc8 | 7290 | struct trace_array *tr = inode->i_private; |
df4fc315 | 7291 | |
345ddcc8 SRRH |
7292 | trace_array_put(tr); |
7293 | ||
7294 | return seq_release(inode, file); | |
df4fc315 SR |
7295 | } |
7296 | ||
5e2336a0 | 7297 | static const struct file_operations ftrace_pid_fops = { |
756d17ee | 7298 | .open = ftrace_pid_open, |
7299 | .write = ftrace_pid_write, | |
7300 | .read = seq_read, | |
098c879e | 7301 | .llseek = tracing_lseek, |
756d17ee | 7302 | .release = ftrace_pid_release, |
df4fc315 SR |
7303 | }; |
7304 | ||
b3b1e6ed SRV |
7305 | static const struct file_operations ftrace_no_pid_fops = { |
7306 | .open = ftrace_no_pid_open, | |
7307 | .write = ftrace_no_pid_write, | |
7308 | .read = seq_read, | |
7309 | .llseek = tracing_lseek, | |
7310 | .release = ftrace_pid_release, | |
7311 | }; | |
7312 | ||
345ddcc8 | 7313 | void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
df4fc315 | 7314 | { |
5452af66 | 7315 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
345ddcc8 | 7316 | tr, &ftrace_pid_fops); |
b3b1e6ed SRV |
7317 | trace_create_file("set_ftrace_notrace_pid", 0644, d_tracer, |
7318 | tr, &ftrace_no_pid_fops); | |
df4fc315 | 7319 | } |
df4fc315 | 7320 | |
501c2375 SRRH |
7321 | void __init ftrace_init_tracefs_toplevel(struct trace_array *tr, |
7322 | struct dentry *d_tracer) | |
7323 | { | |
7324 | /* Only the top level directory has the dyn_tracefs and profile */ | |
7325 | WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); | |
7326 | ||
7327 | ftrace_init_dyn_tracefs(d_tracer); | |
7328 | ftrace_profile_tracefs(d_tracer); | |
7329 | } | |
7330 | ||
a2bb6a3d | 7331 | /** |
81adbdc0 | 7332 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
7333 | * |
7334 | * This function should be used by panic code. It stops ftrace | |
7335 | * but in a not so nice way. If you need to simply kill ftrace | |
7336 | * from a non-atomic section, use ftrace_kill. | |
7337 | */ | |
81adbdc0 | 7338 | void ftrace_kill(void) |
a2bb6a3d SR |
7339 | { |
7340 | ftrace_disabled = 1; | |
7341 | ftrace_enabled = 0; | |
5ccba64a | 7342 | ftrace_trace_function = ftrace_stub; |
a2bb6a3d SR |
7343 | } |
7344 | ||
e0a413f6 SR |
7345 | /** |
7346 | * Test if ftrace is dead or not. | |
7347 | */ | |
7348 | int ftrace_is_dead(void) | |
7349 | { | |
7350 | return ftrace_disabled; | |
7351 | } | |
7352 | ||
16444a8a | 7353 | /** |
3d083395 SR |
7354 | * register_ftrace_function - register a function for profiling |
7355 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 7356 | * |
3d083395 SR |
7357 | * Register a function to be called by all functions in the |
7358 | * kernel. | |
7359 | * | |
7360 | * Note: @ops->func and all the functions it calls must be labeled | |
7361 | * with "notrace", otherwise it will go into a | |
7362 | * recursive loop. | |
16444a8a | 7363 | */ |
3d083395 | 7364 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 7365 | { |
45a4a237 | 7366 | int ret = -1; |
4eebcc81 | 7367 | |
f04f24fb MH |
7368 | ftrace_ops_init(ops); |
7369 | ||
e6ea44e9 | 7370 | mutex_lock(&ftrace_lock); |
e7d3737e | 7371 | |
8a56d776 | 7372 | ret = ftrace_startup(ops, 0); |
b848914c | 7373 | |
e6ea44e9 | 7374 | mutex_unlock(&ftrace_lock); |
8d240dd8 | 7375 | |
b0fc494f | 7376 | return ret; |
3d083395 | 7377 | } |
cdbe61bf | 7378 | EXPORT_SYMBOL_GPL(register_ftrace_function); |
3d083395 SR |
7379 | |
7380 | /** | |
32632920 | 7381 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
7382 | * @ops - ops structure that holds the function to unregister |
7383 | * | |
7384 | * Unregister a function that was added to be called by ftrace profiling. | |
7385 | */ | |
7386 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
7387 | { | |
7388 | int ret; | |
7389 | ||
e6ea44e9 | 7390 | mutex_lock(&ftrace_lock); |
8a56d776 | 7391 | ret = ftrace_shutdown(ops, 0); |
e6ea44e9 | 7392 | mutex_unlock(&ftrace_lock); |
b0fc494f SR |
7393 | |
7394 | return ret; | |
7395 | } | |
cdbe61bf | 7396 | EXPORT_SYMBOL_GPL(unregister_ftrace_function); |
b0fc494f | 7397 | |
7162431d MB |
7398 | static bool is_permanent_ops_registered(void) |
7399 | { | |
7400 | struct ftrace_ops *op; | |
7401 | ||
7402 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
7403 | if (op->flags & FTRACE_OPS_FL_PERMANENT) | |
7404 | return true; | |
7405 | } while_for_each_ftrace_op(op); | |
7406 | ||
7407 | return false; | |
7408 | } | |
7409 | ||
e309b41d | 7410 | int |
b0fc494f | 7411 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
8d65af78 | 7412 | void __user *buffer, size_t *lenp, |
b0fc494f SR |
7413 | loff_t *ppos) |
7414 | { | |
45a4a237 | 7415 | int ret = -ENODEV; |
4eebcc81 | 7416 | |
e6ea44e9 | 7417 | mutex_lock(&ftrace_lock); |
b0fc494f | 7418 | |
45a4a237 SR |
7419 | if (unlikely(ftrace_disabled)) |
7420 | goto out; | |
7421 | ||
7422 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
b0fc494f | 7423 | |
a32c7765 | 7424 | if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) |
b0fc494f SR |
7425 | goto out; |
7426 | ||
b0fc494f SR |
7427 | if (ftrace_enabled) { |
7428 | ||
b0fc494f | 7429 | /* we are starting ftrace again */ |
f86f4180 CZ |
7430 | if (rcu_dereference_protected(ftrace_ops_list, |
7431 | lockdep_is_held(&ftrace_lock)) != &ftrace_list_end) | |
5000c418 | 7432 | update_ftrace_function(); |
b0fc494f | 7433 | |
524a3868 SRRH |
7434 | ftrace_startup_sysctl(); |
7435 | ||
b0fc494f | 7436 | } else { |
7162431d MB |
7437 | if (is_permanent_ops_registered()) { |
7438 | ftrace_enabled = true; | |
7439 | ret = -EBUSY; | |
7440 | goto out; | |
7441 | } | |
7442 | ||
b0fc494f SR |
7443 | /* stopping ftrace calls (just send to ftrace_stub) */ |
7444 | ftrace_trace_function = ftrace_stub; | |
7445 | ||
7446 | ftrace_shutdown_sysctl(); | |
7447 | } | |
7448 | ||
7162431d | 7449 | last_ftrace_enabled = !!ftrace_enabled; |
b0fc494f | 7450 | out: |
e6ea44e9 | 7451 | mutex_unlock(&ftrace_lock); |
3d083395 | 7452 | return ret; |
16444a8a | 7453 | } |