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Commit | Line | Data |
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16444a8a ACM |
1 | /* |
2 | * Infrastructure for profiling code inserted by 'gcc -pg'. | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2004-2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally ported from the -rt patch by: | |
8 | * Copyright (C) 2007 Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code in the latency_tracer, that is: | |
11 | * | |
12 | * Copyright (C) 2004-2006 Ingo Molnar | |
6d49e352 | 13 | * Copyright (C) 2004 Nadia Yvette Chambers |
16444a8a ACM |
14 | */ |
15 | ||
3d083395 SR |
16 | #include <linux/stop_machine.h> |
17 | #include <linux/clocksource.h> | |
29930025 | 18 | #include <linux/sched/task.h> |
3d083395 | 19 | #include <linux/kallsyms.h> |
5072c59f | 20 | #include <linux/seq_file.h> |
4a2b8dda | 21 | #include <linux/suspend.h> |
8434dc93 | 22 | #include <linux/tracefs.h> |
3d083395 | 23 | #include <linux/hardirq.h> |
2d8b820b | 24 | #include <linux/kthread.h> |
5072c59f | 25 | #include <linux/uaccess.h> |
5855fead | 26 | #include <linux/bsearch.h> |
56d82e00 | 27 | #include <linux/module.h> |
2d8b820b | 28 | #include <linux/ftrace.h> |
b0fc494f | 29 | #include <linux/sysctl.h> |
5a0e3ad6 | 30 | #include <linux/slab.h> |
5072c59f | 31 | #include <linux/ctype.h> |
68950619 | 32 | #include <linux/sort.h> |
3d083395 | 33 | #include <linux/list.h> |
59df055f | 34 | #include <linux/hash.h> |
3f379b03 | 35 | #include <linux/rcupdate.h> |
3d083395 | 36 | |
ad8d75ff | 37 | #include <trace/events/sched.h> |
8aef2d28 | 38 | |
2af15d6a | 39 | #include <asm/setup.h> |
395a59d0 | 40 | |
0706f1c4 | 41 | #include "trace_output.h" |
bac429f0 | 42 | #include "trace_stat.h" |
16444a8a | 43 | |
6912896e | 44 | #define FTRACE_WARN_ON(cond) \ |
0778d9ad SR |
45 | ({ \ |
46 | int ___r = cond; \ | |
47 | if (WARN_ON(___r)) \ | |
6912896e | 48 | ftrace_kill(); \ |
0778d9ad SR |
49 | ___r; \ |
50 | }) | |
6912896e SR |
51 | |
52 | #define FTRACE_WARN_ON_ONCE(cond) \ | |
0778d9ad SR |
53 | ({ \ |
54 | int ___r = cond; \ | |
55 | if (WARN_ON_ONCE(___r)) \ | |
6912896e | 56 | ftrace_kill(); \ |
0778d9ad SR |
57 | ___r; \ |
58 | }) | |
6912896e | 59 | |
8fc0c701 SR |
60 | /* hash bits for specific function selection */ |
61 | #define FTRACE_HASH_BITS 7 | |
62 | #define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS) | |
33dc9b12 SR |
63 | #define FTRACE_HASH_DEFAULT_BITS 10 |
64 | #define FTRACE_HASH_MAX_BITS 12 | |
8fc0c701 | 65 | |
f04f24fb | 66 | #ifdef CONFIG_DYNAMIC_FTRACE |
33b7f99c SRRH |
67 | #define INIT_OPS_HASH(opsname) \ |
68 | .func_hash = &opsname.local_hash, \ | |
69 | .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock), | |
5f151b24 SRRH |
70 | #define ASSIGN_OPS_HASH(opsname, val) \ |
71 | .func_hash = val, \ | |
72 | .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock), | |
f04f24fb | 73 | #else |
33b7f99c | 74 | #define INIT_OPS_HASH(opsname) |
5f151b24 | 75 | #define ASSIGN_OPS_HASH(opsname, val) |
f04f24fb MH |
76 | #endif |
77 | ||
2f5f6ad9 SR |
78 | static struct ftrace_ops ftrace_list_end __read_mostly = { |
79 | .func = ftrace_stub, | |
395b97a3 | 80 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_STUB, |
33b7f99c | 81 | INIT_OPS_HASH(ftrace_list_end) |
2f5f6ad9 SR |
82 | }; |
83 | ||
4eebcc81 SR |
84 | /* ftrace_enabled is a method to turn ftrace on or off */ |
85 | int ftrace_enabled __read_mostly; | |
d61f82d0 | 86 | static int last_ftrace_enabled; |
b0fc494f | 87 | |
2f5f6ad9 SR |
88 | /* Current function tracing op */ |
89 | struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end; | |
405e1d83 SRRH |
90 | /* What to set function_trace_op to */ |
91 | static struct ftrace_ops *set_function_trace_op; | |
60a7ecf4 | 92 | |
345ddcc8 | 93 | static bool ftrace_pids_enabled(struct ftrace_ops *ops) |
e3eea140 | 94 | { |
345ddcc8 SRRH |
95 | struct trace_array *tr; |
96 | ||
97 | if (!(ops->flags & FTRACE_OPS_FL_PID) || !ops->private) | |
98 | return false; | |
99 | ||
100 | tr = ops->private; | |
101 | ||
102 | return tr->function_pids != NULL; | |
e3eea140 SRRH |
103 | } |
104 | ||
105 | static void ftrace_update_trampoline(struct ftrace_ops *ops); | |
106 | ||
4eebcc81 SR |
107 | /* |
108 | * ftrace_disabled is set when an anomaly is discovered. | |
109 | * ftrace_disabled is much stronger than ftrace_enabled. | |
110 | */ | |
111 | static int ftrace_disabled __read_mostly; | |
112 | ||
52baf119 | 113 | static DEFINE_MUTEX(ftrace_lock); |
b0fc494f | 114 | |
b848914c | 115 | static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end; |
16444a8a | 116 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; |
2b499381 | 117 | static struct ftrace_ops global_ops; |
16444a8a | 118 | |
2f5f6ad9 SR |
119 | #if ARCH_SUPPORTS_FTRACE_OPS |
120 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 121 | struct ftrace_ops *op, struct pt_regs *regs); |
2f5f6ad9 SR |
122 | #else |
123 | /* See comment below, where ftrace_ops_list_func is defined */ | |
124 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip); | |
125 | #define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops) | |
126 | #endif | |
b848914c | 127 | |
0a016409 SR |
128 | /* |
129 | * Traverse the ftrace_global_list, invoking all entries. The reason that we | |
1bb539ca | 130 | * can use rcu_dereference_raw_notrace() is that elements removed from this list |
0a016409 | 131 | * are simply leaked, so there is no need to interact with a grace-period |
1bb539ca | 132 | * mechanism. The rcu_dereference_raw_notrace() calls are needed to handle |
0a016409 SR |
133 | * concurrent insertions into the ftrace_global_list. |
134 | * | |
135 | * Silly Alpha and silly pointer-speculation compiler optimizations! | |
136 | */ | |
137 | #define do_for_each_ftrace_op(op, list) \ | |
1bb539ca | 138 | op = rcu_dereference_raw_notrace(list); \ |
0a016409 SR |
139 | do |
140 | ||
141 | /* | |
142 | * Optimized for just a single item in the list (as that is the normal case). | |
143 | */ | |
144 | #define while_for_each_ftrace_op(op) \ | |
1bb539ca | 145 | while (likely(op = rcu_dereference_raw_notrace((op)->next)) && \ |
0a016409 SR |
146 | unlikely((op) != &ftrace_list_end)) |
147 | ||
f04f24fb MH |
148 | static inline void ftrace_ops_init(struct ftrace_ops *ops) |
149 | { | |
150 | #ifdef CONFIG_DYNAMIC_FTRACE | |
151 | if (!(ops->flags & FTRACE_OPS_FL_INITIALIZED)) { | |
33b7f99c SRRH |
152 | mutex_init(&ops->local_hash.regex_lock); |
153 | ops->func_hash = &ops->local_hash; | |
f04f24fb MH |
154 | ops->flags |= FTRACE_OPS_FL_INITIALIZED; |
155 | } | |
156 | #endif | |
157 | } | |
158 | ||
ea701f11 SR |
159 | /** |
160 | * ftrace_nr_registered_ops - return number of ops registered | |
161 | * | |
162 | * Returns the number of ftrace_ops registered and tracing functions | |
163 | */ | |
164 | int ftrace_nr_registered_ops(void) | |
165 | { | |
166 | struct ftrace_ops *ops; | |
167 | int cnt = 0; | |
168 | ||
169 | mutex_lock(&ftrace_lock); | |
170 | ||
171 | for (ops = ftrace_ops_list; | |
172 | ops != &ftrace_list_end; ops = ops->next) | |
173 | cnt++; | |
174 | ||
175 | mutex_unlock(&ftrace_lock); | |
176 | ||
177 | return cnt; | |
178 | } | |
179 | ||
2f5f6ad9 | 180 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 181 | struct ftrace_ops *op, struct pt_regs *regs) |
df4fc315 | 182 | { |
345ddcc8 SRRH |
183 | struct trace_array *tr = op->private; |
184 | ||
185 | if (tr && this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid)) | |
df4fc315 SR |
186 | return; |
187 | ||
e3eea140 | 188 | op->saved_func(ip, parent_ip, op, regs); |
df4fc315 SR |
189 | } |
190 | ||
16444a8a | 191 | /** |
3d083395 | 192 | * clear_ftrace_function - reset the ftrace function |
16444a8a | 193 | * |
3d083395 SR |
194 | * This NULLs the ftrace function and in essence stops |
195 | * tracing. There may be lag | |
16444a8a | 196 | */ |
3d083395 | 197 | void clear_ftrace_function(void) |
16444a8a | 198 | { |
3d083395 SR |
199 | ftrace_trace_function = ftrace_stub; |
200 | } | |
201 | ||
ba27f2bc | 202 | static void per_cpu_ops_disable_all(struct ftrace_ops *ops) |
e248491a JO |
203 | { |
204 | int cpu; | |
205 | ||
206 | for_each_possible_cpu(cpu) | |
207 | *per_cpu_ptr(ops->disabled, cpu) = 1; | |
208 | } | |
209 | ||
ba27f2bc | 210 | static int per_cpu_ops_alloc(struct ftrace_ops *ops) |
e248491a JO |
211 | { |
212 | int __percpu *disabled; | |
213 | ||
ba27f2bc SRRH |
214 | if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_PER_CPU))) |
215 | return -EINVAL; | |
216 | ||
e248491a JO |
217 | disabled = alloc_percpu(int); |
218 | if (!disabled) | |
219 | return -ENOMEM; | |
220 | ||
221 | ops->disabled = disabled; | |
ba27f2bc | 222 | per_cpu_ops_disable_all(ops); |
e248491a JO |
223 | return 0; |
224 | } | |
225 | ||
405e1d83 SRRH |
226 | static void ftrace_sync(struct work_struct *work) |
227 | { | |
228 | /* | |
229 | * This function is just a stub to implement a hard force | |
230 | * of synchronize_sched(). This requires synchronizing | |
231 | * tasks even in userspace and idle. | |
232 | * | |
233 | * Yes, function tracing is rude. | |
234 | */ | |
235 | } | |
236 | ||
237 | static void ftrace_sync_ipi(void *data) | |
238 | { | |
239 | /* Probably not needed, but do it anyway */ | |
240 | smp_rmb(); | |
241 | } | |
242 | ||
23a8e844 SRRH |
243 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
244 | static void update_function_graph_func(void); | |
55577204 SRRH |
245 | |
246 | /* Both enabled by default (can be cleared by function_graph tracer flags */ | |
247 | static bool fgraph_sleep_time = true; | |
248 | static bool fgraph_graph_time = true; | |
249 | ||
23a8e844 SRRH |
250 | #else |
251 | static inline void update_function_graph_func(void) { } | |
252 | #endif | |
253 | ||
00ccbf2f SRRH |
254 | |
255 | static ftrace_func_t ftrace_ops_get_list_func(struct ftrace_ops *ops) | |
256 | { | |
257 | /* | |
ba27f2bc | 258 | * If this is a dynamic, RCU, or per CPU ops, or we force list func, |
00ccbf2f SRRH |
259 | * then it needs to call the list anyway. |
260 | */ | |
ba27f2bc SRRH |
261 | if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_PER_CPU | |
262 | FTRACE_OPS_FL_RCU) || FTRACE_FORCE_LIST_FUNC) | |
00ccbf2f SRRH |
263 | return ftrace_ops_list_func; |
264 | ||
265 | return ftrace_ops_get_func(ops); | |
266 | } | |
267 | ||
2b499381 SR |
268 | static void update_ftrace_function(void) |
269 | { | |
270 | ftrace_func_t func; | |
271 | ||
f7aad4e1 SRRH |
272 | /* |
273 | * Prepare the ftrace_ops that the arch callback will use. | |
274 | * If there's only one ftrace_ops registered, the ftrace_ops_list | |
275 | * will point to the ops we want. | |
276 | */ | |
277 | set_function_trace_op = ftrace_ops_list; | |
278 | ||
279 | /* If there's no ftrace_ops registered, just call the stub function */ | |
280 | if (ftrace_ops_list == &ftrace_list_end) { | |
281 | func = ftrace_stub; | |
282 | ||
cdbe61bf SR |
283 | /* |
284 | * If we are at the end of the list and this ops is | |
4740974a SR |
285 | * recursion safe and not dynamic and the arch supports passing ops, |
286 | * then have the mcount trampoline call the function directly. | |
cdbe61bf | 287 | */ |
f7aad4e1 | 288 | } else if (ftrace_ops_list->next == &ftrace_list_end) { |
00ccbf2f | 289 | func = ftrace_ops_get_list_func(ftrace_ops_list); |
f7aad4e1 | 290 | |
2f5f6ad9 SR |
291 | } else { |
292 | /* Just use the default ftrace_ops */ | |
405e1d83 | 293 | set_function_trace_op = &ftrace_list_end; |
b848914c | 294 | func = ftrace_ops_list_func; |
2f5f6ad9 | 295 | } |
2b499381 | 296 | |
5f8bf2d2 SRRH |
297 | update_function_graph_func(); |
298 | ||
405e1d83 SRRH |
299 | /* If there's no change, then do nothing more here */ |
300 | if (ftrace_trace_function == func) | |
301 | return; | |
302 | ||
303 | /* | |
304 | * If we are using the list function, it doesn't care | |
305 | * about the function_trace_ops. | |
306 | */ | |
307 | if (func == ftrace_ops_list_func) { | |
308 | ftrace_trace_function = func; | |
309 | /* | |
310 | * Don't even bother setting function_trace_ops, | |
311 | * it would be racy to do so anyway. | |
312 | */ | |
313 | return; | |
314 | } | |
315 | ||
316 | #ifndef CONFIG_DYNAMIC_FTRACE | |
317 | /* | |
318 | * For static tracing, we need to be a bit more careful. | |
319 | * The function change takes affect immediately. Thus, | |
320 | * we need to coorditate the setting of the function_trace_ops | |
321 | * with the setting of the ftrace_trace_function. | |
322 | * | |
323 | * Set the function to the list ops, which will call the | |
324 | * function we want, albeit indirectly, but it handles the | |
325 | * ftrace_ops and doesn't depend on function_trace_op. | |
326 | */ | |
327 | ftrace_trace_function = ftrace_ops_list_func; | |
328 | /* | |
329 | * Make sure all CPUs see this. Yes this is slow, but static | |
330 | * tracing is slow and nasty to have enabled. | |
331 | */ | |
332 | schedule_on_each_cpu(ftrace_sync); | |
333 | /* Now all cpus are using the list ops. */ | |
334 | function_trace_op = set_function_trace_op; | |
335 | /* Make sure the function_trace_op is visible on all CPUs */ | |
336 | smp_wmb(); | |
337 | /* Nasty way to force a rmb on all cpus */ | |
338 | smp_call_function(ftrace_sync_ipi, NULL, 1); | |
339 | /* OK, we are all set to update the ftrace_trace_function now! */ | |
340 | #endif /* !CONFIG_DYNAMIC_FTRACE */ | |
341 | ||
491d0dcf | 342 | ftrace_trace_function = func; |
491d0dcf SR |
343 | } |
344 | ||
7eea4fce JW |
345 | int using_ftrace_ops_list_func(void) |
346 | { | |
347 | return ftrace_trace_function == ftrace_ops_list_func; | |
348 | } | |
349 | ||
2b499381 | 350 | static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
3d083395 | 351 | { |
2b499381 | 352 | ops->next = *list; |
16444a8a | 353 | /* |
b848914c | 354 | * We are entering ops into the list but another |
16444a8a ACM |
355 | * CPU might be walking that list. We need to make sure |
356 | * the ops->next pointer is valid before another CPU sees | |
b848914c | 357 | * the ops pointer included into the list. |
16444a8a | 358 | */ |
2b499381 | 359 | rcu_assign_pointer(*list, ops); |
16444a8a ACM |
360 | } |
361 | ||
2b499381 | 362 | static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
16444a8a | 363 | { |
16444a8a | 364 | struct ftrace_ops **p; |
16444a8a ACM |
365 | |
366 | /* | |
3d083395 SR |
367 | * If we are removing the last function, then simply point |
368 | * to the ftrace_stub. | |
16444a8a | 369 | */ |
2b499381 SR |
370 | if (*list == ops && ops->next == &ftrace_list_end) { |
371 | *list = &ftrace_list_end; | |
e6ea44e9 | 372 | return 0; |
16444a8a ACM |
373 | } |
374 | ||
2b499381 | 375 | for (p = list; *p != &ftrace_list_end; p = &(*p)->next) |
16444a8a ACM |
376 | if (*p == ops) |
377 | break; | |
378 | ||
e6ea44e9 SR |
379 | if (*p != ops) |
380 | return -1; | |
16444a8a ACM |
381 | |
382 | *p = (*p)->next; | |
2b499381 SR |
383 | return 0; |
384 | } | |
16444a8a | 385 | |
f3bea491 SRRH |
386 | static void ftrace_update_trampoline(struct ftrace_ops *ops); |
387 | ||
2b499381 SR |
388 | static int __register_ftrace_function(struct ftrace_ops *ops) |
389 | { | |
591dffda SRRH |
390 | if (ops->flags & FTRACE_OPS_FL_DELETED) |
391 | return -EINVAL; | |
392 | ||
b848914c SR |
393 | if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED)) |
394 | return -EBUSY; | |
395 | ||
06aeaaea | 396 | #ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
08f6fba5 SR |
397 | /* |
398 | * If the ftrace_ops specifies SAVE_REGS, then it only can be used | |
399 | * if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set. | |
400 | * Setting SAVE_REGS_IF_SUPPORTED makes SAVE_REGS irrelevant. | |
401 | */ | |
402 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS && | |
403 | !(ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)) | |
404 | return -EINVAL; | |
405 | ||
406 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED) | |
407 | ops->flags |= FTRACE_OPS_FL_SAVE_REGS; | |
408 | #endif | |
409 | ||
cdbe61bf SR |
410 | if (!core_kernel_data((unsigned long)ops)) |
411 | ops->flags |= FTRACE_OPS_FL_DYNAMIC; | |
412 | ||
ba27f2bc SRRH |
413 | if (ops->flags & FTRACE_OPS_FL_PER_CPU) { |
414 | if (per_cpu_ops_alloc(ops)) | |
e248491a | 415 | return -ENOMEM; |
ba27f2bc SRRH |
416 | } |
417 | ||
418 | add_ftrace_ops(&ftrace_ops_list, ops); | |
b848914c | 419 | |
e3eea140 SRRH |
420 | /* Always save the function, and reset at unregistering */ |
421 | ops->saved_func = ops->func; | |
422 | ||
345ddcc8 | 423 | if (ftrace_pids_enabled(ops)) |
e3eea140 SRRH |
424 | ops->func = ftrace_pid_func; |
425 | ||
f3bea491 SRRH |
426 | ftrace_update_trampoline(ops); |
427 | ||
2b499381 SR |
428 | if (ftrace_enabled) |
429 | update_ftrace_function(); | |
430 | ||
431 | return 0; | |
432 | } | |
433 | ||
434 | static int __unregister_ftrace_function(struct ftrace_ops *ops) | |
435 | { | |
436 | int ret; | |
437 | ||
b848914c SR |
438 | if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) |
439 | return -EBUSY; | |
440 | ||
ba27f2bc | 441 | ret = remove_ftrace_ops(&ftrace_ops_list, ops); |
b848914c | 442 | |
2b499381 SR |
443 | if (ret < 0) |
444 | return ret; | |
b848914c | 445 | |
491d0dcf SR |
446 | if (ftrace_enabled) |
447 | update_ftrace_function(); | |
16444a8a | 448 | |
e3eea140 SRRH |
449 | ops->func = ops->saved_func; |
450 | ||
e6ea44e9 | 451 | return 0; |
3d083395 SR |
452 | } |
453 | ||
df4fc315 SR |
454 | static void ftrace_update_pid_func(void) |
455 | { | |
e3eea140 SRRH |
456 | struct ftrace_ops *op; |
457 | ||
491d0dcf | 458 | /* Only do something if we are tracing something */ |
df4fc315 | 459 | if (ftrace_trace_function == ftrace_stub) |
10dd3ebe | 460 | return; |
df4fc315 | 461 | |
e3eea140 SRRH |
462 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
463 | if (op->flags & FTRACE_OPS_FL_PID) { | |
345ddcc8 SRRH |
464 | op->func = ftrace_pids_enabled(op) ? |
465 | ftrace_pid_func : op->saved_func; | |
e3eea140 SRRH |
466 | ftrace_update_trampoline(op); |
467 | } | |
468 | } while_for_each_ftrace_op(op); | |
469 | ||
491d0dcf | 470 | update_ftrace_function(); |
df4fc315 SR |
471 | } |
472 | ||
493762fc SR |
473 | #ifdef CONFIG_FUNCTION_PROFILER |
474 | struct ftrace_profile { | |
475 | struct hlist_node node; | |
476 | unsigned long ip; | |
477 | unsigned long counter; | |
0706f1c4 SR |
478 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
479 | unsigned long long time; | |
e330b3bc | 480 | unsigned long long time_squared; |
0706f1c4 | 481 | #endif |
8fc0c701 SR |
482 | }; |
483 | ||
493762fc SR |
484 | struct ftrace_profile_page { |
485 | struct ftrace_profile_page *next; | |
486 | unsigned long index; | |
487 | struct ftrace_profile records[]; | |
d61f82d0 SR |
488 | }; |
489 | ||
cafb168a SR |
490 | struct ftrace_profile_stat { |
491 | atomic_t disabled; | |
492 | struct hlist_head *hash; | |
493 | struct ftrace_profile_page *pages; | |
494 | struct ftrace_profile_page *start; | |
495 | struct tracer_stat stat; | |
496 | }; | |
497 | ||
493762fc SR |
498 | #define PROFILE_RECORDS_SIZE \ |
499 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | |
5072c59f | 500 | |
493762fc SR |
501 | #define PROFILES_PER_PAGE \ |
502 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | |
3d083395 | 503 | |
fb9fb015 SR |
504 | static int ftrace_profile_enabled __read_mostly; |
505 | ||
506 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ | |
bac429f0 SR |
507 | static DEFINE_MUTEX(ftrace_profile_lock); |
508 | ||
cafb168a | 509 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); |
493762fc | 510 | |
20079ebe NK |
511 | #define FTRACE_PROFILE_HASH_BITS 10 |
512 | #define FTRACE_PROFILE_HASH_SIZE (1 << FTRACE_PROFILE_HASH_BITS) | |
493762fc | 513 | |
bac429f0 SR |
514 | static void * |
515 | function_stat_next(void *v, int idx) | |
516 | { | |
493762fc SR |
517 | struct ftrace_profile *rec = v; |
518 | struct ftrace_profile_page *pg; | |
bac429f0 | 519 | |
493762fc | 520 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
bac429f0 SR |
521 | |
522 | again: | |
0296e425 LZ |
523 | if (idx != 0) |
524 | rec++; | |
525 | ||
bac429f0 SR |
526 | if ((void *)rec >= (void *)&pg->records[pg->index]) { |
527 | pg = pg->next; | |
528 | if (!pg) | |
529 | return NULL; | |
530 | rec = &pg->records[0]; | |
493762fc SR |
531 | if (!rec->counter) |
532 | goto again; | |
bac429f0 SR |
533 | } |
534 | ||
bac429f0 SR |
535 | return rec; |
536 | } | |
537 | ||
538 | static void *function_stat_start(struct tracer_stat *trace) | |
539 | { | |
cafb168a SR |
540 | struct ftrace_profile_stat *stat = |
541 | container_of(trace, struct ftrace_profile_stat, stat); | |
542 | ||
543 | if (!stat || !stat->start) | |
544 | return NULL; | |
545 | ||
546 | return function_stat_next(&stat->start->records[0], 0); | |
bac429f0 SR |
547 | } |
548 | ||
0706f1c4 SR |
549 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
550 | /* function graph compares on total time */ | |
551 | static int function_stat_cmp(void *p1, void *p2) | |
552 | { | |
553 | struct ftrace_profile *a = p1; | |
554 | struct ftrace_profile *b = p2; | |
555 | ||
556 | if (a->time < b->time) | |
557 | return -1; | |
558 | if (a->time > b->time) | |
559 | return 1; | |
560 | else | |
561 | return 0; | |
562 | } | |
563 | #else | |
564 | /* not function graph compares against hits */ | |
bac429f0 SR |
565 | static int function_stat_cmp(void *p1, void *p2) |
566 | { | |
493762fc SR |
567 | struct ftrace_profile *a = p1; |
568 | struct ftrace_profile *b = p2; | |
bac429f0 SR |
569 | |
570 | if (a->counter < b->counter) | |
571 | return -1; | |
572 | if (a->counter > b->counter) | |
573 | return 1; | |
574 | else | |
575 | return 0; | |
576 | } | |
0706f1c4 | 577 | #endif |
bac429f0 SR |
578 | |
579 | static int function_stat_headers(struct seq_file *m) | |
580 | { | |
0706f1c4 | 581 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
fa6f0cc7 RV |
582 | seq_puts(m, " Function " |
583 | "Hit Time Avg s^2\n" | |
584 | " -------- " | |
585 | "--- ---- --- ---\n"); | |
0706f1c4 | 586 | #else |
fa6f0cc7 RV |
587 | seq_puts(m, " Function Hit\n" |
588 | " -------- ---\n"); | |
0706f1c4 | 589 | #endif |
bac429f0 SR |
590 | return 0; |
591 | } | |
592 | ||
593 | static int function_stat_show(struct seq_file *m, void *v) | |
594 | { | |
493762fc | 595 | struct ftrace_profile *rec = v; |
bac429f0 | 596 | char str[KSYM_SYMBOL_LEN]; |
3aaba20f | 597 | int ret = 0; |
0706f1c4 | 598 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b SR |
599 | static struct trace_seq s; |
600 | unsigned long long avg; | |
e330b3bc | 601 | unsigned long long stddev; |
0706f1c4 | 602 | #endif |
3aaba20f LZ |
603 | mutex_lock(&ftrace_profile_lock); |
604 | ||
605 | /* we raced with function_profile_reset() */ | |
606 | if (unlikely(rec->counter == 0)) { | |
607 | ret = -EBUSY; | |
608 | goto out; | |
609 | } | |
bac429f0 | 610 | |
8e436ca0 UT |
611 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
612 | avg = rec->time; | |
613 | do_div(avg, rec->counter); | |
614 | if (tracing_thresh && (avg < tracing_thresh)) | |
615 | goto out; | |
616 | #endif | |
617 | ||
bac429f0 | 618 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); |
0706f1c4 SR |
619 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); |
620 | ||
621 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
fa6f0cc7 | 622 | seq_puts(m, " "); |
34886c8b | 623 | |
e330b3bc CD |
624 | /* Sample standard deviation (s^2) */ |
625 | if (rec->counter <= 1) | |
626 | stddev = 0; | |
627 | else { | |
52d85d76 JL |
628 | /* |
629 | * Apply Welford's method: | |
630 | * s^2 = 1 / (n * (n-1)) * (n * \Sum (x_i)^2 - (\Sum x_i)^2) | |
631 | */ | |
632 | stddev = rec->counter * rec->time_squared - | |
633 | rec->time * rec->time; | |
634 | ||
e330b3bc CD |
635 | /* |
636 | * Divide only 1000 for ns^2 -> us^2 conversion. | |
637 | * trace_print_graph_duration will divide 1000 again. | |
638 | */ | |
52d85d76 | 639 | do_div(stddev, rec->counter * (rec->counter - 1) * 1000); |
e330b3bc CD |
640 | } |
641 | ||
34886c8b SR |
642 | trace_seq_init(&s); |
643 | trace_print_graph_duration(rec->time, &s); | |
644 | trace_seq_puts(&s, " "); | |
645 | trace_print_graph_duration(avg, &s); | |
e330b3bc CD |
646 | trace_seq_puts(&s, " "); |
647 | trace_print_graph_duration(stddev, &s); | |
0706f1c4 | 648 | trace_print_seq(m, &s); |
0706f1c4 SR |
649 | #endif |
650 | seq_putc(m, '\n'); | |
3aaba20f LZ |
651 | out: |
652 | mutex_unlock(&ftrace_profile_lock); | |
bac429f0 | 653 | |
3aaba20f | 654 | return ret; |
bac429f0 SR |
655 | } |
656 | ||
cafb168a | 657 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) |
bac429f0 | 658 | { |
493762fc | 659 | struct ftrace_profile_page *pg; |
bac429f0 | 660 | |
cafb168a | 661 | pg = stat->pages = stat->start; |
bac429f0 | 662 | |
493762fc SR |
663 | while (pg) { |
664 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | |
665 | pg->index = 0; | |
666 | pg = pg->next; | |
bac429f0 SR |
667 | } |
668 | ||
cafb168a | 669 | memset(stat->hash, 0, |
493762fc SR |
670 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); |
671 | } | |
bac429f0 | 672 | |
cafb168a | 673 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) |
493762fc SR |
674 | { |
675 | struct ftrace_profile_page *pg; | |
318e0a73 SR |
676 | int functions; |
677 | int pages; | |
493762fc | 678 | int i; |
bac429f0 | 679 | |
493762fc | 680 | /* If we already allocated, do nothing */ |
cafb168a | 681 | if (stat->pages) |
493762fc | 682 | return 0; |
bac429f0 | 683 | |
cafb168a SR |
684 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); |
685 | if (!stat->pages) | |
493762fc | 686 | return -ENOMEM; |
bac429f0 | 687 | |
318e0a73 SR |
688 | #ifdef CONFIG_DYNAMIC_FTRACE |
689 | functions = ftrace_update_tot_cnt; | |
690 | #else | |
691 | /* | |
692 | * We do not know the number of functions that exist because | |
693 | * dynamic tracing is what counts them. With past experience | |
694 | * we have around 20K functions. That should be more than enough. | |
695 | * It is highly unlikely we will execute every function in | |
696 | * the kernel. | |
697 | */ | |
698 | functions = 20000; | |
699 | #endif | |
700 | ||
cafb168a | 701 | pg = stat->start = stat->pages; |
bac429f0 | 702 | |
318e0a73 SR |
703 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); |
704 | ||
39e30cd1 | 705 | for (i = 1; i < pages; i++) { |
493762fc | 706 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
493762fc | 707 | if (!pg->next) |
318e0a73 | 708 | goto out_free; |
493762fc SR |
709 | pg = pg->next; |
710 | } | |
711 | ||
712 | return 0; | |
318e0a73 SR |
713 | |
714 | out_free: | |
715 | pg = stat->start; | |
716 | while (pg) { | |
717 | unsigned long tmp = (unsigned long)pg; | |
718 | ||
719 | pg = pg->next; | |
720 | free_page(tmp); | |
721 | } | |
722 | ||
318e0a73 SR |
723 | stat->pages = NULL; |
724 | stat->start = NULL; | |
725 | ||
726 | return -ENOMEM; | |
bac429f0 SR |
727 | } |
728 | ||
cafb168a | 729 | static int ftrace_profile_init_cpu(int cpu) |
bac429f0 | 730 | { |
cafb168a | 731 | struct ftrace_profile_stat *stat; |
493762fc | 732 | int size; |
bac429f0 | 733 | |
cafb168a SR |
734 | stat = &per_cpu(ftrace_profile_stats, cpu); |
735 | ||
736 | if (stat->hash) { | |
493762fc | 737 | /* If the profile is already created, simply reset it */ |
cafb168a | 738 | ftrace_profile_reset(stat); |
493762fc SR |
739 | return 0; |
740 | } | |
bac429f0 | 741 | |
493762fc SR |
742 | /* |
743 | * We are profiling all functions, but usually only a few thousand | |
744 | * functions are hit. We'll make a hash of 1024 items. | |
745 | */ | |
746 | size = FTRACE_PROFILE_HASH_SIZE; | |
bac429f0 | 747 | |
cafb168a | 748 | stat->hash = kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL); |
493762fc | 749 | |
cafb168a | 750 | if (!stat->hash) |
493762fc SR |
751 | return -ENOMEM; |
752 | ||
318e0a73 | 753 | /* Preallocate the function profiling pages */ |
cafb168a SR |
754 | if (ftrace_profile_pages_init(stat) < 0) { |
755 | kfree(stat->hash); | |
756 | stat->hash = NULL; | |
493762fc SR |
757 | return -ENOMEM; |
758 | } | |
759 | ||
760 | return 0; | |
bac429f0 SR |
761 | } |
762 | ||
cafb168a SR |
763 | static int ftrace_profile_init(void) |
764 | { | |
765 | int cpu; | |
766 | int ret = 0; | |
767 | ||
c4602c1c | 768 | for_each_possible_cpu(cpu) { |
cafb168a SR |
769 | ret = ftrace_profile_init_cpu(cpu); |
770 | if (ret) | |
771 | break; | |
772 | } | |
773 | ||
774 | return ret; | |
775 | } | |
776 | ||
493762fc | 777 | /* interrupts must be disabled */ |
cafb168a SR |
778 | static struct ftrace_profile * |
779 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) | |
bac429f0 | 780 | { |
493762fc | 781 | struct ftrace_profile *rec; |
bac429f0 | 782 | struct hlist_head *hhd; |
bac429f0 SR |
783 | unsigned long key; |
784 | ||
20079ebe | 785 | key = hash_long(ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 786 | hhd = &stat->hash[key]; |
bac429f0 SR |
787 | |
788 | if (hlist_empty(hhd)) | |
789 | return NULL; | |
790 | ||
1bb539ca | 791 | hlist_for_each_entry_rcu_notrace(rec, hhd, node) { |
bac429f0 | 792 | if (rec->ip == ip) |
493762fc SR |
793 | return rec; |
794 | } | |
795 | ||
796 | return NULL; | |
797 | } | |
798 | ||
cafb168a SR |
799 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, |
800 | struct ftrace_profile *rec) | |
493762fc SR |
801 | { |
802 | unsigned long key; | |
803 | ||
20079ebe | 804 | key = hash_long(rec->ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 805 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); |
493762fc SR |
806 | } |
807 | ||
318e0a73 SR |
808 | /* |
809 | * The memory is already allocated, this simply finds a new record to use. | |
810 | */ | |
493762fc | 811 | static struct ftrace_profile * |
318e0a73 | 812 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) |
493762fc SR |
813 | { |
814 | struct ftrace_profile *rec = NULL; | |
815 | ||
318e0a73 | 816 | /* prevent recursion (from NMIs) */ |
cafb168a | 817 | if (atomic_inc_return(&stat->disabled) != 1) |
493762fc SR |
818 | goto out; |
819 | ||
493762fc | 820 | /* |
318e0a73 SR |
821 | * Try to find the function again since an NMI |
822 | * could have added it | |
493762fc | 823 | */ |
cafb168a | 824 | rec = ftrace_find_profiled_func(stat, ip); |
493762fc | 825 | if (rec) |
cafb168a | 826 | goto out; |
493762fc | 827 | |
cafb168a SR |
828 | if (stat->pages->index == PROFILES_PER_PAGE) { |
829 | if (!stat->pages->next) | |
830 | goto out; | |
831 | stat->pages = stat->pages->next; | |
bac429f0 | 832 | } |
493762fc | 833 | |
cafb168a | 834 | rec = &stat->pages->records[stat->pages->index++]; |
493762fc | 835 | rec->ip = ip; |
cafb168a | 836 | ftrace_add_profile(stat, rec); |
493762fc | 837 | |
bac429f0 | 838 | out: |
cafb168a | 839 | atomic_dec(&stat->disabled); |
bac429f0 SR |
840 | |
841 | return rec; | |
842 | } | |
843 | ||
844 | static void | |
2f5f6ad9 | 845 | function_profile_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 846 | struct ftrace_ops *ops, struct pt_regs *regs) |
bac429f0 | 847 | { |
cafb168a | 848 | struct ftrace_profile_stat *stat; |
493762fc | 849 | struct ftrace_profile *rec; |
bac429f0 SR |
850 | unsigned long flags; |
851 | ||
852 | if (!ftrace_profile_enabled) | |
853 | return; | |
854 | ||
855 | local_irq_save(flags); | |
cafb168a | 856 | |
bdffd893 | 857 | stat = this_cpu_ptr(&ftrace_profile_stats); |
0f6ce3de | 858 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
859 | goto out; |
860 | ||
861 | rec = ftrace_find_profiled_func(stat, ip); | |
493762fc | 862 | if (!rec) { |
318e0a73 | 863 | rec = ftrace_profile_alloc(stat, ip); |
493762fc SR |
864 | if (!rec) |
865 | goto out; | |
866 | } | |
bac429f0 SR |
867 | |
868 | rec->counter++; | |
869 | out: | |
870 | local_irq_restore(flags); | |
871 | } | |
872 | ||
0706f1c4 SR |
873 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
874 | static int profile_graph_entry(struct ftrace_graph_ent *trace) | |
875 | { | |
8861dd30 NK |
876 | int index = trace->depth; |
877 | ||
a1e2e31d | 878 | function_profile_call(trace->func, 0, NULL, NULL); |
8861dd30 NK |
879 | |
880 | if (index >= 0 && index < FTRACE_RETFUNC_DEPTH) | |
881 | current->ret_stack[index].subtime = 0; | |
882 | ||
0706f1c4 SR |
883 | return 1; |
884 | } | |
885 | ||
886 | static void profile_graph_return(struct ftrace_graph_ret *trace) | |
887 | { | |
cafb168a | 888 | struct ftrace_profile_stat *stat; |
a2a16d6a | 889 | unsigned long long calltime; |
0706f1c4 | 890 | struct ftrace_profile *rec; |
cafb168a | 891 | unsigned long flags; |
0706f1c4 SR |
892 | |
893 | local_irq_save(flags); | |
bdffd893 | 894 | stat = this_cpu_ptr(&ftrace_profile_stats); |
0f6ce3de | 895 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
896 | goto out; |
897 | ||
37e44bc5 SR |
898 | /* If the calltime was zero'd ignore it */ |
899 | if (!trace->calltime) | |
900 | goto out; | |
901 | ||
a2a16d6a SR |
902 | calltime = trace->rettime - trace->calltime; |
903 | ||
55577204 | 904 | if (!fgraph_graph_time) { |
a2a16d6a SR |
905 | int index; |
906 | ||
907 | index = trace->depth; | |
908 | ||
909 | /* Append this call time to the parent time to subtract */ | |
910 | if (index) | |
911 | current->ret_stack[index - 1].subtime += calltime; | |
912 | ||
913 | if (current->ret_stack[index].subtime < calltime) | |
914 | calltime -= current->ret_stack[index].subtime; | |
915 | else | |
916 | calltime = 0; | |
917 | } | |
918 | ||
cafb168a | 919 | rec = ftrace_find_profiled_func(stat, trace->func); |
e330b3bc | 920 | if (rec) { |
a2a16d6a | 921 | rec->time += calltime; |
e330b3bc CD |
922 | rec->time_squared += calltime * calltime; |
923 | } | |
a2a16d6a | 924 | |
cafb168a | 925 | out: |
0706f1c4 SR |
926 | local_irq_restore(flags); |
927 | } | |
928 | ||
929 | static int register_ftrace_profiler(void) | |
930 | { | |
931 | return register_ftrace_graph(&profile_graph_return, | |
932 | &profile_graph_entry); | |
933 | } | |
934 | ||
935 | static void unregister_ftrace_profiler(void) | |
936 | { | |
937 | unregister_ftrace_graph(); | |
938 | } | |
939 | #else | |
bd38c0e6 | 940 | static struct ftrace_ops ftrace_profile_ops __read_mostly = { |
fb9fb015 | 941 | .func = function_profile_call, |
f04f24fb | 942 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, |
33b7f99c | 943 | INIT_OPS_HASH(ftrace_profile_ops) |
bac429f0 SR |
944 | }; |
945 | ||
0706f1c4 SR |
946 | static int register_ftrace_profiler(void) |
947 | { | |
948 | return register_ftrace_function(&ftrace_profile_ops); | |
949 | } | |
950 | ||
951 | static void unregister_ftrace_profiler(void) | |
952 | { | |
953 | unregister_ftrace_function(&ftrace_profile_ops); | |
954 | } | |
955 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
956 | ||
bac429f0 SR |
957 | static ssize_t |
958 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | |
959 | size_t cnt, loff_t *ppos) | |
960 | { | |
961 | unsigned long val; | |
bac429f0 SR |
962 | int ret; |
963 | ||
22fe9b54 PH |
964 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
965 | if (ret) | |
bac429f0 SR |
966 | return ret; |
967 | ||
968 | val = !!val; | |
969 | ||
970 | mutex_lock(&ftrace_profile_lock); | |
971 | if (ftrace_profile_enabled ^ val) { | |
972 | if (val) { | |
493762fc SR |
973 | ret = ftrace_profile_init(); |
974 | if (ret < 0) { | |
975 | cnt = ret; | |
976 | goto out; | |
977 | } | |
978 | ||
0706f1c4 SR |
979 | ret = register_ftrace_profiler(); |
980 | if (ret < 0) { | |
981 | cnt = ret; | |
982 | goto out; | |
983 | } | |
bac429f0 SR |
984 | ftrace_profile_enabled = 1; |
985 | } else { | |
986 | ftrace_profile_enabled = 0; | |
0f6ce3de SR |
987 | /* |
988 | * unregister_ftrace_profiler calls stop_machine | |
989 | * so this acts like an synchronize_sched. | |
990 | */ | |
0706f1c4 | 991 | unregister_ftrace_profiler(); |
bac429f0 SR |
992 | } |
993 | } | |
493762fc | 994 | out: |
bac429f0 SR |
995 | mutex_unlock(&ftrace_profile_lock); |
996 | ||
cf8517cf | 997 | *ppos += cnt; |
bac429f0 SR |
998 | |
999 | return cnt; | |
1000 | } | |
1001 | ||
493762fc SR |
1002 | static ssize_t |
1003 | ftrace_profile_read(struct file *filp, char __user *ubuf, | |
1004 | size_t cnt, loff_t *ppos) | |
1005 | { | |
fb9fb015 | 1006 | char buf[64]; /* big enough to hold a number */ |
493762fc SR |
1007 | int r; |
1008 | ||
1009 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | |
1010 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
1011 | } | |
1012 | ||
bac429f0 SR |
1013 | static const struct file_operations ftrace_profile_fops = { |
1014 | .open = tracing_open_generic, | |
1015 | .read = ftrace_profile_read, | |
1016 | .write = ftrace_profile_write, | |
6038f373 | 1017 | .llseek = default_llseek, |
bac429f0 SR |
1018 | }; |
1019 | ||
cafb168a SR |
1020 | /* used to initialize the real stat files */ |
1021 | static struct tracer_stat function_stats __initdata = { | |
fb9fb015 SR |
1022 | .name = "functions", |
1023 | .stat_start = function_stat_start, | |
1024 | .stat_next = function_stat_next, | |
1025 | .stat_cmp = function_stat_cmp, | |
1026 | .stat_headers = function_stat_headers, | |
1027 | .stat_show = function_stat_show | |
cafb168a SR |
1028 | }; |
1029 | ||
8434dc93 | 1030 | static __init void ftrace_profile_tracefs(struct dentry *d_tracer) |
bac429f0 | 1031 | { |
cafb168a | 1032 | struct ftrace_profile_stat *stat; |
bac429f0 | 1033 | struct dentry *entry; |
cafb168a | 1034 | char *name; |
bac429f0 | 1035 | int ret; |
cafb168a SR |
1036 | int cpu; |
1037 | ||
1038 | for_each_possible_cpu(cpu) { | |
1039 | stat = &per_cpu(ftrace_profile_stats, cpu); | |
1040 | ||
6363c6b5 | 1041 | name = kasprintf(GFP_KERNEL, "function%d", cpu); |
cafb168a SR |
1042 | if (!name) { |
1043 | /* | |
1044 | * The files created are permanent, if something happens | |
1045 | * we still do not free memory. | |
1046 | */ | |
cafb168a SR |
1047 | WARN(1, |
1048 | "Could not allocate stat file for cpu %d\n", | |
1049 | cpu); | |
1050 | return; | |
1051 | } | |
1052 | stat->stat = function_stats; | |
cafb168a SR |
1053 | stat->stat.name = name; |
1054 | ret = register_stat_tracer(&stat->stat); | |
1055 | if (ret) { | |
1056 | WARN(1, | |
1057 | "Could not register function stat for cpu %d\n", | |
1058 | cpu); | |
1059 | kfree(name); | |
1060 | return; | |
1061 | } | |
bac429f0 SR |
1062 | } |
1063 | ||
8434dc93 | 1064 | entry = tracefs_create_file("function_profile_enabled", 0644, |
bac429f0 SR |
1065 | d_tracer, NULL, &ftrace_profile_fops); |
1066 | if (!entry) | |
a395d6a7 | 1067 | pr_warn("Could not create tracefs 'function_profile_enabled' entry\n"); |
bac429f0 SR |
1068 | } |
1069 | ||
bac429f0 | 1070 | #else /* CONFIG_FUNCTION_PROFILER */ |
8434dc93 | 1071 | static __init void ftrace_profile_tracefs(struct dentry *d_tracer) |
bac429f0 SR |
1072 | { |
1073 | } | |
bac429f0 SR |
1074 | #endif /* CONFIG_FUNCTION_PROFILER */ |
1075 | ||
493762fc SR |
1076 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; |
1077 | ||
1619dc3f PA |
1078 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
1079 | static int ftrace_graph_active; | |
1080 | #else | |
1081 | # define ftrace_graph_active 0 | |
1082 | #endif | |
1083 | ||
493762fc SR |
1084 | #ifdef CONFIG_DYNAMIC_FTRACE |
1085 | ||
79922b80 SRRH |
1086 | static struct ftrace_ops *removed_ops; |
1087 | ||
e1effa01 SRRH |
1088 | /* |
1089 | * Set when doing a global update, like enabling all recs or disabling them. | |
1090 | * It is not set when just updating a single ftrace_ops. | |
1091 | */ | |
1092 | static bool update_all_ops; | |
1093 | ||
493762fc SR |
1094 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD |
1095 | # error Dynamic ftrace depends on MCOUNT_RECORD | |
1096 | #endif | |
1097 | ||
1098 | static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly; | |
1099 | ||
1100 | struct ftrace_func_probe { | |
1101 | struct hlist_node node; | |
1102 | struct ftrace_probe_ops *ops; | |
1103 | unsigned long flags; | |
1104 | unsigned long ip; | |
1105 | void *data; | |
7818b388 | 1106 | struct list_head free_list; |
493762fc SR |
1107 | }; |
1108 | ||
b448c4e3 SR |
1109 | struct ftrace_func_entry { |
1110 | struct hlist_node hlist; | |
1111 | unsigned long ip; | |
1112 | }; | |
1113 | ||
33dc9b12 SR |
1114 | /* |
1115 | * We make these constant because no one should touch them, | |
1116 | * but they are used as the default "empty hash", to avoid allocating | |
1117 | * it all the time. These are in a read only section such that if | |
1118 | * anyone does try to modify it, it will cause an exception. | |
1119 | */ | |
1120 | static const struct hlist_head empty_buckets[1]; | |
1121 | static const struct ftrace_hash empty_hash = { | |
1122 | .buckets = (struct hlist_head *)empty_buckets, | |
1cf41dd7 | 1123 | }; |
33dc9b12 | 1124 | #define EMPTY_HASH ((struct ftrace_hash *)&empty_hash) |
493762fc | 1125 | |
2b499381 | 1126 | static struct ftrace_ops global_ops = { |
33b7f99c SRRH |
1127 | .func = ftrace_stub, |
1128 | .local_hash.notrace_hash = EMPTY_HASH, | |
1129 | .local_hash.filter_hash = EMPTY_HASH, | |
1130 | INIT_OPS_HASH(global_ops) | |
1131 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | | |
e3eea140 SRRH |
1132 | FTRACE_OPS_FL_INITIALIZED | |
1133 | FTRACE_OPS_FL_PID, | |
f45948e8 SR |
1134 | }; |
1135 | ||
aec0be2d SRRH |
1136 | /* |
1137 | * This is used by __kernel_text_address() to return true if the | |
0af26492 | 1138 | * address is on a dynamically allocated trampoline that would |
aec0be2d SRRH |
1139 | * not return true for either core_kernel_text() or |
1140 | * is_module_text_address(). | |
1141 | */ | |
1142 | bool is_ftrace_trampoline(unsigned long addr) | |
1143 | { | |
1144 | struct ftrace_ops *op; | |
1145 | bool ret = false; | |
1146 | ||
1147 | /* | |
1148 | * Some of the ops may be dynamically allocated, | |
1149 | * they are freed after a synchronize_sched(). | |
1150 | */ | |
1151 | preempt_disable_notrace(); | |
1152 | ||
1153 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
1154 | /* | |
1155 | * This is to check for dynamically allocated trampolines. | |
1156 | * Trampolines that are in kernel text will have | |
1157 | * core_kernel_text() return true. | |
1158 | */ | |
1159 | if (op->trampoline && op->trampoline_size) | |
1160 | if (addr >= op->trampoline && | |
1161 | addr < op->trampoline + op->trampoline_size) { | |
1162 | ret = true; | |
1163 | goto out; | |
1164 | } | |
1165 | } while_for_each_ftrace_op(op); | |
1166 | ||
1167 | out: | |
1168 | preempt_enable_notrace(); | |
1169 | ||
1170 | return ret; | |
1171 | } | |
1172 | ||
493762fc SR |
1173 | struct ftrace_page { |
1174 | struct ftrace_page *next; | |
a7900875 | 1175 | struct dyn_ftrace *records; |
493762fc | 1176 | int index; |
a7900875 | 1177 | int size; |
493762fc SR |
1178 | }; |
1179 | ||
a7900875 SR |
1180 | #define ENTRY_SIZE sizeof(struct dyn_ftrace) |
1181 | #define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE) | |
493762fc SR |
1182 | |
1183 | /* estimate from running different kernels */ | |
1184 | #define NR_TO_INIT 10000 | |
1185 | ||
1186 | static struct ftrace_page *ftrace_pages_start; | |
1187 | static struct ftrace_page *ftrace_pages; | |
1188 | ||
2b0cce0e SRV |
1189 | static __always_inline unsigned long |
1190 | ftrace_hash_key(struct ftrace_hash *hash, unsigned long ip) | |
1191 | { | |
1192 | if (hash->size_bits > 0) | |
1193 | return hash_long(ip, hash->size_bits); | |
1194 | ||
1195 | return 0; | |
1196 | } | |
1197 | ||
2b2c279c SRV |
1198 | /* Only use this function if ftrace_hash_empty() has already been tested */ |
1199 | static __always_inline struct ftrace_func_entry * | |
1200 | __ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
b448c4e3 SR |
1201 | { |
1202 | unsigned long key; | |
1203 | struct ftrace_func_entry *entry; | |
1204 | struct hlist_head *hhd; | |
b448c4e3 | 1205 | |
2b0cce0e | 1206 | key = ftrace_hash_key(hash, ip); |
b448c4e3 SR |
1207 | hhd = &hash->buckets[key]; |
1208 | ||
1bb539ca | 1209 | hlist_for_each_entry_rcu_notrace(entry, hhd, hlist) { |
b448c4e3 SR |
1210 | if (entry->ip == ip) |
1211 | return entry; | |
1212 | } | |
1213 | return NULL; | |
1214 | } | |
1215 | ||
2b2c279c SRV |
1216 | /** |
1217 | * ftrace_lookup_ip - Test to see if an ip exists in an ftrace_hash | |
1218 | * @hash: The hash to look at | |
1219 | * @ip: The instruction pointer to test | |
1220 | * | |
1221 | * Search a given @hash to see if a given instruction pointer (@ip) | |
1222 | * exists in it. | |
1223 | * | |
1224 | * Returns the entry that holds the @ip if found. NULL otherwise. | |
1225 | */ | |
1226 | struct ftrace_func_entry * | |
1227 | ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
1228 | { | |
1229 | if (ftrace_hash_empty(hash)) | |
1230 | return NULL; | |
1231 | ||
1232 | return __ftrace_lookup_ip(hash, ip); | |
1233 | } | |
1234 | ||
33dc9b12 SR |
1235 | static void __add_hash_entry(struct ftrace_hash *hash, |
1236 | struct ftrace_func_entry *entry) | |
b448c4e3 | 1237 | { |
b448c4e3 SR |
1238 | struct hlist_head *hhd; |
1239 | unsigned long key; | |
1240 | ||
2b0cce0e | 1241 | key = ftrace_hash_key(hash, entry->ip); |
b448c4e3 SR |
1242 | hhd = &hash->buckets[key]; |
1243 | hlist_add_head(&entry->hlist, hhd); | |
1244 | hash->count++; | |
33dc9b12 SR |
1245 | } |
1246 | ||
1247 | static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) | |
1248 | { | |
1249 | struct ftrace_func_entry *entry; | |
1250 | ||
1251 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
1252 | if (!entry) | |
1253 | return -ENOMEM; | |
1254 | ||
1255 | entry->ip = ip; | |
1256 | __add_hash_entry(hash, entry); | |
b448c4e3 SR |
1257 | |
1258 | return 0; | |
1259 | } | |
1260 | ||
1261 | static void | |
33dc9b12 | 1262 | free_hash_entry(struct ftrace_hash *hash, |
b448c4e3 SR |
1263 | struct ftrace_func_entry *entry) |
1264 | { | |
1265 | hlist_del(&entry->hlist); | |
1266 | kfree(entry); | |
1267 | hash->count--; | |
1268 | } | |
1269 | ||
33dc9b12 SR |
1270 | static void |
1271 | remove_hash_entry(struct ftrace_hash *hash, | |
1272 | struct ftrace_func_entry *entry) | |
1273 | { | |
1274 | hlist_del(&entry->hlist); | |
1275 | hash->count--; | |
1276 | } | |
1277 | ||
b448c4e3 SR |
1278 | static void ftrace_hash_clear(struct ftrace_hash *hash) |
1279 | { | |
1280 | struct hlist_head *hhd; | |
b67bfe0d | 1281 | struct hlist_node *tn; |
b448c4e3 SR |
1282 | struct ftrace_func_entry *entry; |
1283 | int size = 1 << hash->size_bits; | |
1284 | int i; | |
1285 | ||
33dc9b12 SR |
1286 | if (!hash->count) |
1287 | return; | |
1288 | ||
b448c4e3 SR |
1289 | for (i = 0; i < size; i++) { |
1290 | hhd = &hash->buckets[i]; | |
b67bfe0d | 1291 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) |
33dc9b12 | 1292 | free_hash_entry(hash, entry); |
b448c4e3 SR |
1293 | } |
1294 | FTRACE_WARN_ON(hash->count); | |
1295 | } | |
1296 | ||
33dc9b12 SR |
1297 | static void free_ftrace_hash(struct ftrace_hash *hash) |
1298 | { | |
1299 | if (!hash || hash == EMPTY_HASH) | |
1300 | return; | |
1301 | ftrace_hash_clear(hash); | |
1302 | kfree(hash->buckets); | |
1303 | kfree(hash); | |
1304 | } | |
1305 | ||
07fd5515 SR |
1306 | static void __free_ftrace_hash_rcu(struct rcu_head *rcu) |
1307 | { | |
1308 | struct ftrace_hash *hash; | |
1309 | ||
1310 | hash = container_of(rcu, struct ftrace_hash, rcu); | |
1311 | free_ftrace_hash(hash); | |
1312 | } | |
1313 | ||
1314 | static void free_ftrace_hash_rcu(struct ftrace_hash *hash) | |
1315 | { | |
1316 | if (!hash || hash == EMPTY_HASH) | |
1317 | return; | |
1318 | call_rcu_sched(&hash->rcu, __free_ftrace_hash_rcu); | |
1319 | } | |
1320 | ||
5500fa51 JO |
1321 | void ftrace_free_filter(struct ftrace_ops *ops) |
1322 | { | |
f04f24fb | 1323 | ftrace_ops_init(ops); |
33b7f99c SRRH |
1324 | free_ftrace_hash(ops->func_hash->filter_hash); |
1325 | free_ftrace_hash(ops->func_hash->notrace_hash); | |
5500fa51 JO |
1326 | } |
1327 | ||
33dc9b12 SR |
1328 | static struct ftrace_hash *alloc_ftrace_hash(int size_bits) |
1329 | { | |
1330 | struct ftrace_hash *hash; | |
1331 | int size; | |
1332 | ||
1333 | hash = kzalloc(sizeof(*hash), GFP_KERNEL); | |
1334 | if (!hash) | |
1335 | return NULL; | |
1336 | ||
1337 | size = 1 << size_bits; | |
47b0edcb | 1338 | hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL); |
33dc9b12 SR |
1339 | |
1340 | if (!hash->buckets) { | |
1341 | kfree(hash); | |
1342 | return NULL; | |
1343 | } | |
1344 | ||
1345 | hash->size_bits = size_bits; | |
1346 | ||
1347 | return hash; | |
1348 | } | |
1349 | ||
1350 | static struct ftrace_hash * | |
1351 | alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) | |
1352 | { | |
1353 | struct ftrace_func_entry *entry; | |
1354 | struct ftrace_hash *new_hash; | |
33dc9b12 SR |
1355 | int size; |
1356 | int ret; | |
1357 | int i; | |
1358 | ||
1359 | new_hash = alloc_ftrace_hash(size_bits); | |
1360 | if (!new_hash) | |
1361 | return NULL; | |
1362 | ||
1363 | /* Empty hash? */ | |
06a51d93 | 1364 | if (ftrace_hash_empty(hash)) |
33dc9b12 SR |
1365 | return new_hash; |
1366 | ||
1367 | size = 1 << hash->size_bits; | |
1368 | for (i = 0; i < size; i++) { | |
b67bfe0d | 1369 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { |
33dc9b12 SR |
1370 | ret = add_hash_entry(new_hash, entry->ip); |
1371 | if (ret < 0) | |
1372 | goto free_hash; | |
1373 | } | |
1374 | } | |
1375 | ||
1376 | FTRACE_WARN_ON(new_hash->count != hash->count); | |
1377 | ||
1378 | return new_hash; | |
1379 | ||
1380 | free_hash: | |
1381 | free_ftrace_hash(new_hash); | |
1382 | return NULL; | |
1383 | } | |
1384 | ||
41fb61c2 | 1385 | static void |
84261912 | 1386 | ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, int filter_hash); |
41fb61c2 | 1387 | static void |
84261912 | 1388 | ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, int filter_hash); |
41fb61c2 | 1389 | |
f8b8be8a MH |
1390 | static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops, |
1391 | struct ftrace_hash *new_hash); | |
1392 | ||
3e278c0d NK |
1393 | static struct ftrace_hash * |
1394 | __ftrace_hash_move(struct ftrace_hash *src) | |
33dc9b12 SR |
1395 | { |
1396 | struct ftrace_func_entry *entry; | |
b67bfe0d | 1397 | struct hlist_node *tn; |
33dc9b12 | 1398 | struct hlist_head *hhd; |
07fd5515 | 1399 | struct ftrace_hash *new_hash; |
33dc9b12 SR |
1400 | int size = src->count; |
1401 | int bits = 0; | |
1402 | int i; | |
1403 | ||
1404 | /* | |
3e278c0d | 1405 | * If the new source is empty, just return the empty_hash. |
33dc9b12 | 1406 | */ |
3e278c0d NK |
1407 | if (!src->count) |
1408 | return EMPTY_HASH; | |
33dc9b12 | 1409 | |
33dc9b12 SR |
1410 | /* |
1411 | * Make the hash size about 1/2 the # found | |
1412 | */ | |
1413 | for (size /= 2; size; size >>= 1) | |
1414 | bits++; | |
1415 | ||
1416 | /* Don't allocate too much */ | |
1417 | if (bits > FTRACE_HASH_MAX_BITS) | |
1418 | bits = FTRACE_HASH_MAX_BITS; | |
1419 | ||
07fd5515 SR |
1420 | new_hash = alloc_ftrace_hash(bits); |
1421 | if (!new_hash) | |
3e278c0d | 1422 | return NULL; |
33dc9b12 SR |
1423 | |
1424 | size = 1 << src->size_bits; | |
1425 | for (i = 0; i < size; i++) { | |
1426 | hhd = &src->buckets[i]; | |
b67bfe0d | 1427 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) { |
33dc9b12 | 1428 | remove_hash_entry(src, entry); |
07fd5515 | 1429 | __add_hash_entry(new_hash, entry); |
33dc9b12 SR |
1430 | } |
1431 | } | |
1432 | ||
3e278c0d NK |
1433 | return new_hash; |
1434 | } | |
1435 | ||
1436 | static int | |
1437 | ftrace_hash_move(struct ftrace_ops *ops, int enable, | |
1438 | struct ftrace_hash **dst, struct ftrace_hash *src) | |
1439 | { | |
1440 | struct ftrace_hash *new_hash; | |
1441 | int ret; | |
1442 | ||
1443 | /* Reject setting notrace hash on IPMODIFY ftrace_ops */ | |
1444 | if (ops->flags & FTRACE_OPS_FL_IPMODIFY && !enable) | |
1445 | return -EINVAL; | |
1446 | ||
1447 | new_hash = __ftrace_hash_move(src); | |
1448 | if (!new_hash) | |
1449 | return -ENOMEM; | |
1450 | ||
f8b8be8a MH |
1451 | /* Make sure this can be applied if it is IPMODIFY ftrace_ops */ |
1452 | if (enable) { | |
1453 | /* IPMODIFY should be updated only when filter_hash updating */ | |
1454 | ret = ftrace_hash_ipmodify_update(ops, new_hash); | |
1455 | if (ret < 0) { | |
1456 | free_ftrace_hash(new_hash); | |
1457 | return ret; | |
1458 | } | |
1459 | } | |
1460 | ||
5c27c775 MH |
1461 | /* |
1462 | * Remove the current set, update the hash and add | |
1463 | * them back. | |
1464 | */ | |
84261912 | 1465 | ftrace_hash_rec_disable_modify(ops, enable); |
5c27c775 | 1466 | |
07fd5515 | 1467 | rcu_assign_pointer(*dst, new_hash); |
07fd5515 | 1468 | |
84261912 | 1469 | ftrace_hash_rec_enable_modify(ops, enable); |
41fb61c2 | 1470 | |
5c27c775 | 1471 | return 0; |
33dc9b12 SR |
1472 | } |
1473 | ||
fef5aeee SRRH |
1474 | static bool hash_contains_ip(unsigned long ip, |
1475 | struct ftrace_ops_hash *hash) | |
1476 | { | |
1477 | /* | |
1478 | * The function record is a match if it exists in the filter | |
1479 | * hash and not in the notrace hash. Note, an emty hash is | |
1480 | * considered a match for the filter hash, but an empty | |
1481 | * notrace hash is considered not in the notrace hash. | |
1482 | */ | |
1483 | return (ftrace_hash_empty(hash->filter_hash) || | |
2b2c279c | 1484 | __ftrace_lookup_ip(hash->filter_hash, ip)) && |
fef5aeee | 1485 | (ftrace_hash_empty(hash->notrace_hash) || |
2b2c279c | 1486 | !__ftrace_lookup_ip(hash->notrace_hash, ip)); |
fef5aeee SRRH |
1487 | } |
1488 | ||
b848914c SR |
1489 | /* |
1490 | * Test the hashes for this ops to see if we want to call | |
1491 | * the ops->func or not. | |
1492 | * | |
1493 | * It's a match if the ip is in the ops->filter_hash or | |
1494 | * the filter_hash does not exist or is empty, | |
1495 | * AND | |
1496 | * the ip is not in the ops->notrace_hash. | |
cdbe61bf SR |
1497 | * |
1498 | * This needs to be called with preemption disabled as | |
1499 | * the hashes are freed with call_rcu_sched(). | |
b848914c SR |
1500 | */ |
1501 | static int | |
195a8afc | 1502 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs) |
b848914c | 1503 | { |
fef5aeee | 1504 | struct ftrace_ops_hash hash; |
b848914c SR |
1505 | int ret; |
1506 | ||
195a8afc SRRH |
1507 | #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
1508 | /* | |
1509 | * There's a small race when adding ops that the ftrace handler | |
1510 | * that wants regs, may be called without them. We can not | |
1511 | * allow that handler to be called if regs is NULL. | |
1512 | */ | |
1513 | if (regs == NULL && (ops->flags & FTRACE_OPS_FL_SAVE_REGS)) | |
1514 | return 0; | |
1515 | #endif | |
1516 | ||
fef5aeee SRRH |
1517 | hash.filter_hash = rcu_dereference_raw_notrace(ops->func_hash->filter_hash); |
1518 | hash.notrace_hash = rcu_dereference_raw_notrace(ops->func_hash->notrace_hash); | |
b848914c | 1519 | |
fef5aeee | 1520 | if (hash_contains_ip(ip, &hash)) |
b848914c SR |
1521 | ret = 1; |
1522 | else | |
1523 | ret = 0; | |
b848914c SR |
1524 | |
1525 | return ret; | |
1526 | } | |
1527 | ||
493762fc SR |
1528 | /* |
1529 | * This is a double for. Do not use 'break' to break out of the loop, | |
1530 | * you must use a goto. | |
1531 | */ | |
1532 | #define do_for_each_ftrace_rec(pg, rec) \ | |
1533 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
1534 | int _____i; \ | |
1535 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
1536 | rec = &pg->records[_____i]; | |
1537 | ||
1538 | #define while_for_each_ftrace_rec() \ | |
1539 | } \ | |
1540 | } | |
1541 | ||
5855fead SR |
1542 | |
1543 | static int ftrace_cmp_recs(const void *a, const void *b) | |
1544 | { | |
a650e02a SR |
1545 | const struct dyn_ftrace *key = a; |
1546 | const struct dyn_ftrace *rec = b; | |
5855fead | 1547 | |
a650e02a | 1548 | if (key->flags < rec->ip) |
5855fead | 1549 | return -1; |
a650e02a SR |
1550 | if (key->ip >= rec->ip + MCOUNT_INSN_SIZE) |
1551 | return 1; | |
5855fead SR |
1552 | return 0; |
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 SR |
1568 | { |
1569 | struct ftrace_page *pg; | |
1570 | struct dyn_ftrace *rec; | |
5855fead | 1571 | struct dyn_ftrace key; |
c88fd863 | 1572 | |
a650e02a SR |
1573 | key.ip = start; |
1574 | key.flags = end; /* overload flags, as it is unsigned long */ | |
5855fead SR |
1575 | |
1576 | for (pg = ftrace_pages_start; pg; pg = pg->next) { | |
a650e02a SR |
1577 | if (end < pg->records[0].ip || |
1578 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) | |
9644302e | 1579 | continue; |
5855fead SR |
1580 | rec = bsearch(&key, pg->records, pg->index, |
1581 | sizeof(struct dyn_ftrace), | |
1582 | ftrace_cmp_recs); | |
1583 | if (rec) | |
f0cf973a | 1584 | return rec->ip; |
5855fead | 1585 | } |
c88fd863 SR |
1586 | |
1587 | return 0; | |
1588 | } | |
1589 | ||
a650e02a SR |
1590 | /** |
1591 | * ftrace_location - return true if the ip giving is a traced location | |
1592 | * @ip: the instruction pointer to check | |
1593 | * | |
f0cf973a | 1594 | * Returns rec->ip if @ip given is a pointer to a ftrace location. |
a650e02a SR |
1595 | * That is, the instruction that is either a NOP or call to |
1596 | * the function tracer. It checks the ftrace internal tables to | |
1597 | * determine if the address belongs or not. | |
1598 | */ | |
f0cf973a | 1599 | unsigned long ftrace_location(unsigned long ip) |
a650e02a SR |
1600 | { |
1601 | return ftrace_location_range(ip, ip); | |
1602 | } | |
1603 | ||
1604 | /** | |
1605 | * ftrace_text_reserved - return true if range contains an ftrace location | |
1606 | * @start: start of range to search | |
1607 | * @end: end of range to search (inclusive). @end points to the last byte to check. | |
1608 | * | |
1609 | * Returns 1 if @start and @end contains a ftrace location. | |
1610 | * That is, the instruction that is either a NOP or call to | |
1611 | * the function tracer. It checks the ftrace internal tables to | |
1612 | * determine if the address belongs or not. | |
1613 | */ | |
d88471cb | 1614 | int ftrace_text_reserved(const void *start, const void *end) |
a650e02a | 1615 | { |
f0cf973a SR |
1616 | unsigned long ret; |
1617 | ||
1618 | ret = ftrace_location_range((unsigned long)start, | |
1619 | (unsigned long)end); | |
1620 | ||
1621 | return (int)!!ret; | |
a650e02a SR |
1622 | } |
1623 | ||
4fbb48cb SRRH |
1624 | /* Test if ops registered to this rec needs regs */ |
1625 | static bool test_rec_ops_needs_regs(struct dyn_ftrace *rec) | |
1626 | { | |
1627 | struct ftrace_ops *ops; | |
1628 | bool keep_regs = false; | |
1629 | ||
1630 | for (ops = ftrace_ops_list; | |
1631 | ops != &ftrace_list_end; ops = ops->next) { | |
1632 | /* pass rec in as regs to have non-NULL val */ | |
1633 | if (ftrace_ops_test(ops, rec->ip, rec)) { | |
1634 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) { | |
1635 | keep_regs = true; | |
1636 | break; | |
1637 | } | |
1638 | } | |
1639 | } | |
1640 | ||
1641 | return keep_regs; | |
1642 | } | |
1643 | ||
84b6d3e6 | 1644 | static bool __ftrace_hash_rec_update(struct ftrace_ops *ops, |
ed926f9b SR |
1645 | int filter_hash, |
1646 | bool inc) | |
1647 | { | |
1648 | struct ftrace_hash *hash; | |
1649 | struct ftrace_hash *other_hash; | |
1650 | struct ftrace_page *pg; | |
1651 | struct dyn_ftrace *rec; | |
84b6d3e6 | 1652 | bool update = false; |
ed926f9b SR |
1653 | int count = 0; |
1654 | int all = 0; | |
1655 | ||
1656 | /* Only update if the ops has been registered */ | |
1657 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
84b6d3e6 | 1658 | return false; |
ed926f9b SR |
1659 | |
1660 | /* | |
1661 | * In the filter_hash case: | |
1662 | * If the count is zero, we update all records. | |
1663 | * Otherwise we just update the items in the hash. | |
1664 | * | |
1665 | * In the notrace_hash case: | |
1666 | * We enable the update in the hash. | |
1667 | * As disabling notrace means enabling the tracing, | |
1668 | * and enabling notrace means disabling, the inc variable | |
1669 | * gets inversed. | |
1670 | */ | |
1671 | if (filter_hash) { | |
33b7f99c SRRH |
1672 | hash = ops->func_hash->filter_hash; |
1673 | other_hash = ops->func_hash->notrace_hash; | |
06a51d93 | 1674 | if (ftrace_hash_empty(hash)) |
ed926f9b SR |
1675 | all = 1; |
1676 | } else { | |
1677 | inc = !inc; | |
33b7f99c SRRH |
1678 | hash = ops->func_hash->notrace_hash; |
1679 | other_hash = ops->func_hash->filter_hash; | |
ed926f9b SR |
1680 | /* |
1681 | * If the notrace hash has no items, | |
1682 | * then there's nothing to do. | |
1683 | */ | |
06a51d93 | 1684 | if (ftrace_hash_empty(hash)) |
84b6d3e6 | 1685 | return false; |
ed926f9b SR |
1686 | } |
1687 | ||
1688 | do_for_each_ftrace_rec(pg, rec) { | |
1689 | int in_other_hash = 0; | |
1690 | int in_hash = 0; | |
1691 | int match = 0; | |
1692 | ||
b7ffffbb SRRH |
1693 | if (rec->flags & FTRACE_FL_DISABLED) |
1694 | continue; | |
1695 | ||
ed926f9b SR |
1696 | if (all) { |
1697 | /* | |
1698 | * Only the filter_hash affects all records. | |
1699 | * Update if the record is not in the notrace hash. | |
1700 | */ | |
b848914c | 1701 | if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip)) |
ed926f9b SR |
1702 | match = 1; |
1703 | } else { | |
06a51d93 SR |
1704 | in_hash = !!ftrace_lookup_ip(hash, rec->ip); |
1705 | in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip); | |
ed926f9b SR |
1706 | |
1707 | /* | |
19eab4a4 SRRH |
1708 | * If filter_hash is set, we want to match all functions |
1709 | * that are in the hash but not in the other hash. | |
ed926f9b | 1710 | * |
19eab4a4 SRRH |
1711 | * If filter_hash is not set, then we are decrementing. |
1712 | * That means we match anything that is in the hash | |
1713 | * and also in the other_hash. That is, we need to turn | |
1714 | * off functions in the other hash because they are disabled | |
1715 | * by this hash. | |
ed926f9b SR |
1716 | */ |
1717 | if (filter_hash && in_hash && !in_other_hash) | |
1718 | match = 1; | |
1719 | else if (!filter_hash && in_hash && | |
06a51d93 | 1720 | (in_other_hash || ftrace_hash_empty(other_hash))) |
ed926f9b SR |
1721 | match = 1; |
1722 | } | |
1723 | if (!match) | |
1724 | continue; | |
1725 | ||
1726 | if (inc) { | |
1727 | rec->flags++; | |
0376bde1 | 1728 | if (FTRACE_WARN_ON(ftrace_rec_count(rec) == FTRACE_REF_MAX)) |
84b6d3e6 | 1729 | return false; |
79922b80 SRRH |
1730 | |
1731 | /* | |
1732 | * If there's only a single callback registered to a | |
1733 | * function, and the ops has a trampoline registered | |
1734 | * for it, then we can call it directly. | |
1735 | */ | |
fef5aeee | 1736 | if (ftrace_rec_count(rec) == 1 && ops->trampoline) |
79922b80 | 1737 | rec->flags |= FTRACE_FL_TRAMP; |
fef5aeee | 1738 | else |
79922b80 SRRH |
1739 | /* |
1740 | * If we are adding another function callback | |
1741 | * to this function, and the previous had a | |
bce0b6c5 SRRH |
1742 | * custom trampoline in use, then we need to go |
1743 | * back to the default trampoline. | |
79922b80 | 1744 | */ |
fef5aeee | 1745 | rec->flags &= ~FTRACE_FL_TRAMP; |
79922b80 | 1746 | |
08f6fba5 SR |
1747 | /* |
1748 | * If any ops wants regs saved for this function | |
1749 | * then all ops will get saved regs. | |
1750 | */ | |
1751 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) | |
1752 | rec->flags |= FTRACE_FL_REGS; | |
ed926f9b | 1753 | } else { |
0376bde1 | 1754 | if (FTRACE_WARN_ON(ftrace_rec_count(rec) == 0)) |
84b6d3e6 | 1755 | return false; |
ed926f9b | 1756 | rec->flags--; |
79922b80 | 1757 | |
4fbb48cb SRRH |
1758 | /* |
1759 | * If the rec had REGS enabled and the ops that is | |
1760 | * being removed had REGS set, then see if there is | |
1761 | * still any ops for this record that wants regs. | |
1762 | * If not, we can stop recording them. | |
1763 | */ | |
0376bde1 | 1764 | if (ftrace_rec_count(rec) > 0 && |
4fbb48cb SRRH |
1765 | rec->flags & FTRACE_FL_REGS && |
1766 | ops->flags & FTRACE_OPS_FL_SAVE_REGS) { | |
1767 | if (!test_rec_ops_needs_regs(rec)) | |
1768 | rec->flags &= ~FTRACE_FL_REGS; | |
1769 | } | |
79922b80 | 1770 | |
fef5aeee SRRH |
1771 | /* |
1772 | * If the rec had TRAMP enabled, then it needs to | |
1773 | * be cleared. As TRAMP can only be enabled iff | |
1774 | * there is only a single ops attached to it. | |
1775 | * In otherwords, always disable it on decrementing. | |
1776 | * In the future, we may set it if rec count is | |
1777 | * decremented to one, and the ops that is left | |
1778 | * has a trampoline. | |
1779 | */ | |
1780 | rec->flags &= ~FTRACE_FL_TRAMP; | |
1781 | ||
79922b80 SRRH |
1782 | /* |
1783 | * flags will be cleared in ftrace_check_record() | |
1784 | * if rec count is zero. | |
1785 | */ | |
ed926f9b SR |
1786 | } |
1787 | count++; | |
84b6d3e6 JO |
1788 | |
1789 | /* Must match FTRACE_UPDATE_CALLS in ftrace_modify_all_code() */ | |
1790 | update |= ftrace_test_record(rec, 1) != FTRACE_UPDATE_IGNORE; | |
1791 | ||
ed926f9b SR |
1792 | /* Shortcut, if we handled all records, we are done. */ |
1793 | if (!all && count == hash->count) | |
84b6d3e6 | 1794 | return update; |
ed926f9b | 1795 | } while_for_each_ftrace_rec(); |
84b6d3e6 JO |
1796 | |
1797 | return update; | |
ed926f9b SR |
1798 | } |
1799 | ||
84b6d3e6 | 1800 | static bool ftrace_hash_rec_disable(struct ftrace_ops *ops, |
ed926f9b SR |
1801 | int filter_hash) |
1802 | { | |
84b6d3e6 | 1803 | return __ftrace_hash_rec_update(ops, filter_hash, 0); |
ed926f9b SR |
1804 | } |
1805 | ||
84b6d3e6 | 1806 | static bool ftrace_hash_rec_enable(struct ftrace_ops *ops, |
ed926f9b SR |
1807 | int filter_hash) |
1808 | { | |
84b6d3e6 | 1809 | return __ftrace_hash_rec_update(ops, filter_hash, 1); |
ed926f9b SR |
1810 | } |
1811 | ||
84261912 SRRH |
1812 | static void ftrace_hash_rec_update_modify(struct ftrace_ops *ops, |
1813 | int filter_hash, int inc) | |
1814 | { | |
1815 | struct ftrace_ops *op; | |
1816 | ||
1817 | __ftrace_hash_rec_update(ops, filter_hash, inc); | |
1818 | ||
1819 | if (ops->func_hash != &global_ops.local_hash) | |
1820 | return; | |
1821 | ||
1822 | /* | |
1823 | * If the ops shares the global_ops hash, then we need to update | |
1824 | * all ops that are enabled and use this hash. | |
1825 | */ | |
1826 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
1827 | /* Already done */ | |
1828 | if (op == ops) | |
1829 | continue; | |
1830 | if (op->func_hash == &global_ops.local_hash) | |
1831 | __ftrace_hash_rec_update(op, filter_hash, inc); | |
1832 | } while_for_each_ftrace_op(op); | |
1833 | } | |
1834 | ||
1835 | static void ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, | |
1836 | int filter_hash) | |
1837 | { | |
1838 | ftrace_hash_rec_update_modify(ops, filter_hash, 0); | |
1839 | } | |
1840 | ||
1841 | static void ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, | |
1842 | int filter_hash) | |
1843 | { | |
1844 | ftrace_hash_rec_update_modify(ops, filter_hash, 1); | |
1845 | } | |
1846 | ||
f8b8be8a MH |
1847 | /* |
1848 | * Try to update IPMODIFY flag on each ftrace_rec. Return 0 if it is OK | |
1849 | * or no-needed to update, -EBUSY if it detects a conflict of the flag | |
1850 | * on a ftrace_rec, and -EINVAL if the new_hash tries to trace all recs. | |
1851 | * Note that old_hash and new_hash has below meanings | |
1852 | * - If the hash is NULL, it hits all recs (if IPMODIFY is set, this is rejected) | |
1853 | * - If the hash is EMPTY_HASH, it hits nothing | |
1854 | * - Anything else hits the recs which match the hash entries. | |
1855 | */ | |
1856 | static int __ftrace_hash_update_ipmodify(struct ftrace_ops *ops, | |
1857 | struct ftrace_hash *old_hash, | |
1858 | struct ftrace_hash *new_hash) | |
1859 | { | |
1860 | struct ftrace_page *pg; | |
1861 | struct dyn_ftrace *rec, *end = NULL; | |
1862 | int in_old, in_new; | |
1863 | ||
1864 | /* Only update if the ops has been registered */ | |
1865 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
1866 | return 0; | |
1867 | ||
1868 | if (!(ops->flags & FTRACE_OPS_FL_IPMODIFY)) | |
1869 | return 0; | |
1870 | ||
1871 | /* | |
1872 | * Since the IPMODIFY is a very address sensitive action, we do not | |
1873 | * allow ftrace_ops to set all functions to new hash. | |
1874 | */ | |
1875 | if (!new_hash || !old_hash) | |
1876 | return -EINVAL; | |
1877 | ||
1878 | /* Update rec->flags */ | |
1879 | do_for_each_ftrace_rec(pg, rec) { | |
546fece4 SRRH |
1880 | |
1881 | if (rec->flags & FTRACE_FL_DISABLED) | |
1882 | continue; | |
1883 | ||
f8b8be8a MH |
1884 | /* We need to update only differences of filter_hash */ |
1885 | in_old = !!ftrace_lookup_ip(old_hash, rec->ip); | |
1886 | in_new = !!ftrace_lookup_ip(new_hash, rec->ip); | |
1887 | if (in_old == in_new) | |
1888 | continue; | |
1889 | ||
1890 | if (in_new) { | |
1891 | /* New entries must ensure no others are using it */ | |
1892 | if (rec->flags & FTRACE_FL_IPMODIFY) | |
1893 | goto rollback; | |
1894 | rec->flags |= FTRACE_FL_IPMODIFY; | |
1895 | } else /* Removed entry */ | |
1896 | rec->flags &= ~FTRACE_FL_IPMODIFY; | |
1897 | } while_for_each_ftrace_rec(); | |
1898 | ||
1899 | return 0; | |
1900 | ||
1901 | rollback: | |
1902 | end = rec; | |
1903 | ||
1904 | /* Roll back what we did above */ | |
1905 | do_for_each_ftrace_rec(pg, rec) { | |
546fece4 SRRH |
1906 | |
1907 | if (rec->flags & FTRACE_FL_DISABLED) | |
1908 | continue; | |
1909 | ||
f8b8be8a MH |
1910 | if (rec == end) |
1911 | goto err_out; | |
1912 | ||
1913 | in_old = !!ftrace_lookup_ip(old_hash, rec->ip); | |
1914 | in_new = !!ftrace_lookup_ip(new_hash, rec->ip); | |
1915 | if (in_old == in_new) | |
1916 | continue; | |
1917 | ||
1918 | if (in_new) | |
1919 | rec->flags &= ~FTRACE_FL_IPMODIFY; | |
1920 | else | |
1921 | rec->flags |= FTRACE_FL_IPMODIFY; | |
1922 | } while_for_each_ftrace_rec(); | |
1923 | ||
1924 | err_out: | |
1925 | return -EBUSY; | |
1926 | } | |
1927 | ||
1928 | static int ftrace_hash_ipmodify_enable(struct ftrace_ops *ops) | |
1929 | { | |
1930 | struct ftrace_hash *hash = ops->func_hash->filter_hash; | |
1931 | ||
1932 | if (ftrace_hash_empty(hash)) | |
1933 | hash = NULL; | |
1934 | ||
1935 | return __ftrace_hash_update_ipmodify(ops, EMPTY_HASH, hash); | |
1936 | } | |
1937 | ||
1938 | /* Disabling always succeeds */ | |
1939 | static void ftrace_hash_ipmodify_disable(struct ftrace_ops *ops) | |
1940 | { | |
1941 | struct ftrace_hash *hash = ops->func_hash->filter_hash; | |
1942 | ||
1943 | if (ftrace_hash_empty(hash)) | |
1944 | hash = NULL; | |
1945 | ||
1946 | __ftrace_hash_update_ipmodify(ops, hash, EMPTY_HASH); | |
1947 | } | |
1948 | ||
1949 | static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops, | |
1950 | struct ftrace_hash *new_hash) | |
1951 | { | |
1952 | struct ftrace_hash *old_hash = ops->func_hash->filter_hash; | |
1953 | ||
1954 | if (ftrace_hash_empty(old_hash)) | |
1955 | old_hash = NULL; | |
1956 | ||
1957 | if (ftrace_hash_empty(new_hash)) | |
1958 | new_hash = NULL; | |
1959 | ||
1960 | return __ftrace_hash_update_ipmodify(ops, old_hash, new_hash); | |
1961 | } | |
1962 | ||
b05086c7 | 1963 | static void print_ip_ins(const char *fmt, const unsigned char *p) |
b17e8a37 SR |
1964 | { |
1965 | int i; | |
1966 | ||
1967 | printk(KERN_CONT "%s", fmt); | |
1968 | ||
1969 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
1970 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
1971 | } | |
1972 | ||
4fd3279b SRRH |
1973 | static struct ftrace_ops * |
1974 | ftrace_find_tramp_ops_any(struct dyn_ftrace *rec); | |
39daa7b9 SRRH |
1975 | static struct ftrace_ops * |
1976 | ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, struct ftrace_ops *ops); | |
4fd3279b | 1977 | |
02a392a0 | 1978 | enum ftrace_bug_type ftrace_bug_type; |
b05086c7 | 1979 | const void *ftrace_expected; |
02a392a0 SRRH |
1980 | |
1981 | static void print_bug_type(void) | |
1982 | { | |
1983 | switch (ftrace_bug_type) { | |
1984 | case FTRACE_BUG_UNKNOWN: | |
1985 | break; | |
1986 | case FTRACE_BUG_INIT: | |
1987 | pr_info("Initializing ftrace call sites\n"); | |
1988 | break; | |
1989 | case FTRACE_BUG_NOP: | |
1990 | pr_info("Setting ftrace call site to NOP\n"); | |
1991 | break; | |
1992 | case FTRACE_BUG_CALL: | |
1993 | pr_info("Setting ftrace call site to call ftrace function\n"); | |
1994 | break; | |
1995 | case FTRACE_BUG_UPDATE: | |
1996 | pr_info("Updating ftrace call site to call a different ftrace function\n"); | |
1997 | break; | |
1998 | } | |
1999 | } | |
2000 | ||
c88fd863 SR |
2001 | /** |
2002 | * ftrace_bug - report and shutdown function tracer | |
2003 | * @failed: The failed type (EFAULT, EINVAL, EPERM) | |
4fd3279b | 2004 | * @rec: The record that failed |
c88fd863 SR |
2005 | * |
2006 | * The arch code that enables or disables the function tracing | |
2007 | * can call ftrace_bug() when it has detected a problem in | |
2008 | * modifying the code. @failed should be one of either: | |
2009 | * EFAULT - if the problem happens on reading the @ip address | |
2010 | * EINVAL - if what is read at @ip is not what was expected | |
2011 | * EPERM - if the problem happens on writting to the @ip address | |
2012 | */ | |
4fd3279b | 2013 | void ftrace_bug(int failed, struct dyn_ftrace *rec) |
b17e8a37 | 2014 | { |
4fd3279b SRRH |
2015 | unsigned long ip = rec ? rec->ip : 0; |
2016 | ||
b17e8a37 SR |
2017 | switch (failed) { |
2018 | case -EFAULT: | |
2019 | FTRACE_WARN_ON_ONCE(1); | |
2020 | pr_info("ftrace faulted on modifying "); | |
2021 | print_ip_sym(ip); | |
2022 | break; | |
2023 | case -EINVAL: | |
2024 | FTRACE_WARN_ON_ONCE(1); | |
2025 | pr_info("ftrace failed to modify "); | |
2026 | print_ip_sym(ip); | |
b05086c7 | 2027 | print_ip_ins(" actual: ", (unsigned char *)ip); |
4fd3279b | 2028 | pr_cont("\n"); |
b05086c7 SRRH |
2029 | if (ftrace_expected) { |
2030 | print_ip_ins(" expected: ", ftrace_expected); | |
2031 | pr_cont("\n"); | |
2032 | } | |
b17e8a37 SR |
2033 | break; |
2034 | case -EPERM: | |
2035 | FTRACE_WARN_ON_ONCE(1); | |
2036 | pr_info("ftrace faulted on writing "); | |
2037 | print_ip_sym(ip); | |
2038 | break; | |
2039 | default: | |
2040 | FTRACE_WARN_ON_ONCE(1); | |
2041 | pr_info("ftrace faulted on unknown error "); | |
2042 | print_ip_sym(ip); | |
2043 | } | |
02a392a0 | 2044 | print_bug_type(); |
4fd3279b SRRH |
2045 | if (rec) { |
2046 | struct ftrace_ops *ops = NULL; | |
2047 | ||
2048 | pr_info("ftrace record flags: %lx\n", rec->flags); | |
2049 | pr_cont(" (%ld)%s", ftrace_rec_count(rec), | |
2050 | rec->flags & FTRACE_FL_REGS ? " R" : " "); | |
2051 | if (rec->flags & FTRACE_FL_TRAMP_EN) { | |
2052 | ops = ftrace_find_tramp_ops_any(rec); | |
39daa7b9 SRRH |
2053 | if (ops) { |
2054 | do { | |
2055 | pr_cont("\ttramp: %pS (%pS)", | |
2056 | (void *)ops->trampoline, | |
2057 | (void *)ops->func); | |
2058 | ops = ftrace_find_tramp_ops_next(rec, ops); | |
2059 | } while (ops); | |
2060 | } else | |
4fd3279b SRRH |
2061 | pr_cont("\ttramp: ERROR!"); |
2062 | ||
2063 | } | |
2064 | ip = ftrace_get_addr_curr(rec); | |
39daa7b9 | 2065 | pr_cont("\n expected tramp: %lx\n", ip); |
4fd3279b | 2066 | } |
b17e8a37 SR |
2067 | } |
2068 | ||
c88fd863 | 2069 | static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update) |
5072c59f | 2070 | { |
64fbcd16 | 2071 | unsigned long flag = 0UL; |
e7d3737e | 2072 | |
02a392a0 SRRH |
2073 | ftrace_bug_type = FTRACE_BUG_UNKNOWN; |
2074 | ||
b7ffffbb SRRH |
2075 | if (rec->flags & FTRACE_FL_DISABLED) |
2076 | return FTRACE_UPDATE_IGNORE; | |
2077 | ||
982c350b | 2078 | /* |
30fb6aa7 | 2079 | * If we are updating calls: |
982c350b | 2080 | * |
ed926f9b SR |
2081 | * If the record has a ref count, then we need to enable it |
2082 | * because someone is using it. | |
982c350b | 2083 | * |
ed926f9b SR |
2084 | * Otherwise we make sure its disabled. |
2085 | * | |
30fb6aa7 | 2086 | * If we are disabling calls, then disable all records that |
ed926f9b | 2087 | * are enabled. |
982c350b | 2088 | */ |
0376bde1 | 2089 | if (enable && ftrace_rec_count(rec)) |
ed926f9b | 2090 | flag = FTRACE_FL_ENABLED; |
982c350b | 2091 | |
08f6fba5 | 2092 | /* |
79922b80 SRRH |
2093 | * If enabling and the REGS flag does not match the REGS_EN, or |
2094 | * the TRAMP flag doesn't match the TRAMP_EN, then do not ignore | |
2095 | * this record. Set flags to fail the compare against ENABLED. | |
08f6fba5 | 2096 | */ |
79922b80 SRRH |
2097 | if (flag) { |
2098 | if (!(rec->flags & FTRACE_FL_REGS) != | |
2099 | !(rec->flags & FTRACE_FL_REGS_EN)) | |
2100 | flag |= FTRACE_FL_REGS; | |
2101 | ||
2102 | if (!(rec->flags & FTRACE_FL_TRAMP) != | |
2103 | !(rec->flags & FTRACE_FL_TRAMP_EN)) | |
2104 | flag |= FTRACE_FL_TRAMP; | |
2105 | } | |
08f6fba5 | 2106 | |
64fbcd16 XG |
2107 | /* If the state of this record hasn't changed, then do nothing */ |
2108 | if ((rec->flags & FTRACE_FL_ENABLED) == flag) | |
c88fd863 | 2109 | return FTRACE_UPDATE_IGNORE; |
982c350b | 2110 | |
64fbcd16 | 2111 | if (flag) { |
08f6fba5 SR |
2112 | /* Save off if rec is being enabled (for return value) */ |
2113 | flag ^= rec->flags & FTRACE_FL_ENABLED; | |
2114 | ||
2115 | if (update) { | |
c88fd863 | 2116 | rec->flags |= FTRACE_FL_ENABLED; |
08f6fba5 SR |
2117 | if (flag & FTRACE_FL_REGS) { |
2118 | if (rec->flags & FTRACE_FL_REGS) | |
2119 | rec->flags |= FTRACE_FL_REGS_EN; | |
2120 | else | |
2121 | rec->flags &= ~FTRACE_FL_REGS_EN; | |
2122 | } | |
79922b80 SRRH |
2123 | if (flag & FTRACE_FL_TRAMP) { |
2124 | if (rec->flags & FTRACE_FL_TRAMP) | |
2125 | rec->flags |= FTRACE_FL_TRAMP_EN; | |
2126 | else | |
2127 | rec->flags &= ~FTRACE_FL_TRAMP_EN; | |
2128 | } | |
08f6fba5 SR |
2129 | } |
2130 | ||
2131 | /* | |
2132 | * If this record is being updated from a nop, then | |
2133 | * return UPDATE_MAKE_CALL. | |
08f6fba5 SR |
2134 | * Otherwise, |
2135 | * return UPDATE_MODIFY_CALL to tell the caller to convert | |
f1b2f2bd | 2136 | * from the save regs, to a non-save regs function or |
79922b80 | 2137 | * vice versa, or from a trampoline call. |
08f6fba5 | 2138 | */ |
02a392a0 SRRH |
2139 | if (flag & FTRACE_FL_ENABLED) { |
2140 | ftrace_bug_type = FTRACE_BUG_CALL; | |
08f6fba5 | 2141 | return FTRACE_UPDATE_MAKE_CALL; |
02a392a0 | 2142 | } |
f1b2f2bd | 2143 | |
02a392a0 | 2144 | ftrace_bug_type = FTRACE_BUG_UPDATE; |
f1b2f2bd | 2145 | return FTRACE_UPDATE_MODIFY_CALL; |
c88fd863 SR |
2146 | } |
2147 | ||
08f6fba5 SR |
2148 | if (update) { |
2149 | /* If there's no more users, clear all flags */ | |
0376bde1 | 2150 | if (!ftrace_rec_count(rec)) |
08f6fba5 SR |
2151 | rec->flags = 0; |
2152 | else | |
b24d443b SRRH |
2153 | /* |
2154 | * Just disable the record, but keep the ops TRAMP | |
2155 | * and REGS states. The _EN flags must be disabled though. | |
2156 | */ | |
2157 | rec->flags &= ~(FTRACE_FL_ENABLED | FTRACE_FL_TRAMP_EN | | |
2158 | FTRACE_FL_REGS_EN); | |
08f6fba5 | 2159 | } |
c88fd863 | 2160 | |
02a392a0 | 2161 | ftrace_bug_type = FTRACE_BUG_NOP; |
c88fd863 SR |
2162 | return FTRACE_UPDATE_MAKE_NOP; |
2163 | } | |
2164 | ||
2165 | /** | |
2166 | * ftrace_update_record, set a record that now is tracing or not | |
2167 | * @rec: the record to update | |
2168 | * @enable: set to 1 if the record is tracing, zero to force disable | |
2169 | * | |
2170 | * The records that represent all functions that can be traced need | |
2171 | * to be updated when tracing has been enabled. | |
2172 | */ | |
2173 | int ftrace_update_record(struct dyn_ftrace *rec, int enable) | |
2174 | { | |
2175 | return ftrace_check_record(rec, enable, 1); | |
2176 | } | |
2177 | ||
2178 | /** | |
2179 | * ftrace_test_record, check if the record has been enabled or not | |
2180 | * @rec: the record to test | |
2181 | * @enable: set to 1 to check if enabled, 0 if it is disabled | |
2182 | * | |
2183 | * The arch code may need to test if a record is already set to | |
2184 | * tracing to determine how to modify the function code that it | |
2185 | * represents. | |
2186 | */ | |
2187 | int ftrace_test_record(struct dyn_ftrace *rec, int enable) | |
2188 | { | |
2189 | return ftrace_check_record(rec, enable, 0); | |
2190 | } | |
2191 | ||
5fecaa04 SRRH |
2192 | static struct ftrace_ops * |
2193 | ftrace_find_tramp_ops_any(struct dyn_ftrace *rec) | |
2194 | { | |
2195 | struct ftrace_ops *op; | |
fef5aeee | 2196 | unsigned long ip = rec->ip; |
5fecaa04 SRRH |
2197 | |
2198 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
2199 | ||
2200 | if (!op->trampoline) | |
2201 | continue; | |
2202 | ||
fef5aeee | 2203 | if (hash_contains_ip(ip, op->func_hash)) |
5fecaa04 SRRH |
2204 | return op; |
2205 | } while_for_each_ftrace_op(op); | |
2206 | ||
2207 | return NULL; | |
2208 | } | |
2209 | ||
39daa7b9 SRRH |
2210 | static struct ftrace_ops * |
2211 | ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, | |
2212 | struct ftrace_ops *op) | |
2213 | { | |
2214 | unsigned long ip = rec->ip; | |
2215 | ||
2216 | while_for_each_ftrace_op(op) { | |
2217 | ||
2218 | if (!op->trampoline) | |
2219 | continue; | |
2220 | ||
2221 | if (hash_contains_ip(ip, op->func_hash)) | |
2222 | return op; | |
2223 | } | |
2224 | ||
2225 | return NULL; | |
2226 | } | |
2227 | ||
79922b80 SRRH |
2228 | static struct ftrace_ops * |
2229 | ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec) | |
2230 | { | |
2231 | struct ftrace_ops *op; | |
fef5aeee | 2232 | unsigned long ip = rec->ip; |
79922b80 | 2233 | |
fef5aeee SRRH |
2234 | /* |
2235 | * Need to check removed ops first. | |
2236 | * If they are being removed, and this rec has a tramp, | |
2237 | * and this rec is in the ops list, then it would be the | |
2238 | * one with the tramp. | |
2239 | */ | |
2240 | if (removed_ops) { | |
2241 | if (hash_contains_ip(ip, &removed_ops->old_hash)) | |
79922b80 SRRH |
2242 | return removed_ops; |
2243 | } | |
2244 | ||
fef5aeee SRRH |
2245 | /* |
2246 | * Need to find the current trampoline for a rec. | |
2247 | * Now, a trampoline is only attached to a rec if there | |
2248 | * was a single 'ops' attached to it. But this can be called | |
2249 | * when we are adding another op to the rec or removing the | |
2250 | * current one. Thus, if the op is being added, we can | |
2251 | * ignore it because it hasn't attached itself to the rec | |
4fc40904 SRRH |
2252 | * yet. |
2253 | * | |
2254 | * If an ops is being modified (hooking to different functions) | |
2255 | * then we don't care about the new functions that are being | |
2256 | * added, just the old ones (that are probably being removed). | |
2257 | * | |
2258 | * If we are adding an ops to a function that already is using | |
2259 | * a trampoline, it needs to be removed (trampolines are only | |
2260 | * for single ops connected), then an ops that is not being | |
2261 | * modified also needs to be checked. | |
fef5aeee | 2262 | */ |
79922b80 | 2263 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
fef5aeee SRRH |
2264 | |
2265 | if (!op->trampoline) | |
2266 | continue; | |
2267 | ||
2268 | /* | |
2269 | * If the ops is being added, it hasn't gotten to | |
2270 | * the point to be removed from this tree yet. | |
2271 | */ | |
2272 | if (op->flags & FTRACE_OPS_FL_ADDING) | |
79922b80 SRRH |
2273 | continue; |
2274 | ||
4fc40904 | 2275 | |
fef5aeee | 2276 | /* |
4fc40904 SRRH |
2277 | * If the ops is being modified and is in the old |
2278 | * hash, then it is probably being removed from this | |
2279 | * function. | |
fef5aeee | 2280 | */ |
fef5aeee SRRH |
2281 | if ((op->flags & FTRACE_OPS_FL_MODIFYING) && |
2282 | hash_contains_ip(ip, &op->old_hash)) | |
79922b80 | 2283 | return op; |
4fc40904 SRRH |
2284 | /* |
2285 | * If the ops is not being added or modified, and it's | |
2286 | * in its normal filter hash, then this must be the one | |
2287 | * we want! | |
2288 | */ | |
2289 | if (!(op->flags & FTRACE_OPS_FL_MODIFYING) && | |
2290 | hash_contains_ip(ip, op->func_hash)) | |
2291 | return op; | |
79922b80 SRRH |
2292 | |
2293 | } while_for_each_ftrace_op(op); | |
2294 | ||
2295 | return NULL; | |
2296 | } | |
2297 | ||
2298 | static struct ftrace_ops * | |
2299 | ftrace_find_tramp_ops_new(struct dyn_ftrace *rec) | |
2300 | { | |
2301 | struct ftrace_ops *op; | |
fef5aeee | 2302 | unsigned long ip = rec->ip; |
79922b80 SRRH |
2303 | |
2304 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
2305 | /* pass rec in as regs to have non-NULL val */ | |
fef5aeee | 2306 | if (hash_contains_ip(ip, op->func_hash)) |
79922b80 SRRH |
2307 | return op; |
2308 | } while_for_each_ftrace_op(op); | |
2309 | ||
2310 | return NULL; | |
2311 | } | |
2312 | ||
7413af1f SRRH |
2313 | /** |
2314 | * ftrace_get_addr_new - Get the call address to set to | |
2315 | * @rec: The ftrace record descriptor | |
2316 | * | |
2317 | * If the record has the FTRACE_FL_REGS set, that means that it | |
2318 | * wants to convert to a callback that saves all regs. If FTRACE_FL_REGS | |
2319 | * is not not set, then it wants to convert to the normal callback. | |
2320 | * | |
2321 | * Returns the address of the trampoline to set to | |
2322 | */ | |
2323 | unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec) | |
2324 | { | |
79922b80 SRRH |
2325 | struct ftrace_ops *ops; |
2326 | ||
2327 | /* Trampolines take precedence over regs */ | |
2328 | if (rec->flags & FTRACE_FL_TRAMP) { | |
2329 | ops = ftrace_find_tramp_ops_new(rec); | |
2330 | if (FTRACE_WARN_ON(!ops || !ops->trampoline)) { | |
bce0b6c5 SRRH |
2331 | pr_warn("Bad trampoline accounting at: %p (%pS) (%lx)\n", |
2332 | (void *)rec->ip, (void *)rec->ip, rec->flags); | |
79922b80 SRRH |
2333 | /* Ftrace is shutting down, return anything */ |
2334 | return (unsigned long)FTRACE_ADDR; | |
2335 | } | |
2336 | return ops->trampoline; | |
2337 | } | |
2338 | ||
7413af1f SRRH |
2339 | if (rec->flags & FTRACE_FL_REGS) |
2340 | return (unsigned long)FTRACE_REGS_ADDR; | |
2341 | else | |
2342 | return (unsigned long)FTRACE_ADDR; | |
2343 | } | |
2344 | ||
2345 | /** | |
2346 | * ftrace_get_addr_curr - Get the call address that is already there | |
2347 | * @rec: The ftrace record descriptor | |
2348 | * | |
2349 | * The FTRACE_FL_REGS_EN is set when the record already points to | |
2350 | * a function that saves all the regs. Basically the '_EN' version | |
2351 | * represents the current state of the function. | |
2352 | * | |
2353 | * Returns the address of the trampoline that is currently being called | |
2354 | */ | |
2355 | unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec) | |
2356 | { | |
79922b80 SRRH |
2357 | struct ftrace_ops *ops; |
2358 | ||
2359 | /* Trampolines take precedence over regs */ | |
2360 | if (rec->flags & FTRACE_FL_TRAMP_EN) { | |
2361 | ops = ftrace_find_tramp_ops_curr(rec); | |
2362 | if (FTRACE_WARN_ON(!ops)) { | |
a395d6a7 JP |
2363 | pr_warn("Bad trampoline accounting at: %p (%pS)\n", |
2364 | (void *)rec->ip, (void *)rec->ip); | |
79922b80 SRRH |
2365 | /* Ftrace is shutting down, return anything */ |
2366 | return (unsigned long)FTRACE_ADDR; | |
2367 | } | |
2368 | return ops->trampoline; | |
2369 | } | |
2370 | ||
7413af1f SRRH |
2371 | if (rec->flags & FTRACE_FL_REGS_EN) |
2372 | return (unsigned long)FTRACE_REGS_ADDR; | |
2373 | else | |
2374 | return (unsigned long)FTRACE_ADDR; | |
2375 | } | |
2376 | ||
c88fd863 SR |
2377 | static int |
2378 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) | |
2379 | { | |
08f6fba5 | 2380 | unsigned long ftrace_old_addr; |
c88fd863 SR |
2381 | unsigned long ftrace_addr; |
2382 | int ret; | |
2383 | ||
7c0868e0 | 2384 | ftrace_addr = ftrace_get_addr_new(rec); |
c88fd863 | 2385 | |
7c0868e0 SRRH |
2386 | /* This needs to be done before we call ftrace_update_record */ |
2387 | ftrace_old_addr = ftrace_get_addr_curr(rec); | |
2388 | ||
2389 | ret = ftrace_update_record(rec, enable); | |
08f6fba5 | 2390 | |
02a392a0 SRRH |
2391 | ftrace_bug_type = FTRACE_BUG_UNKNOWN; |
2392 | ||
c88fd863 SR |
2393 | switch (ret) { |
2394 | case FTRACE_UPDATE_IGNORE: | |
2395 | return 0; | |
2396 | ||
2397 | case FTRACE_UPDATE_MAKE_CALL: | |
02a392a0 | 2398 | ftrace_bug_type = FTRACE_BUG_CALL; |
64fbcd16 | 2399 | return ftrace_make_call(rec, ftrace_addr); |
c88fd863 SR |
2400 | |
2401 | case FTRACE_UPDATE_MAKE_NOP: | |
02a392a0 | 2402 | ftrace_bug_type = FTRACE_BUG_NOP; |
39b5552c | 2403 | return ftrace_make_nop(NULL, rec, ftrace_old_addr); |
08f6fba5 | 2404 | |
08f6fba5 | 2405 | case FTRACE_UPDATE_MODIFY_CALL: |
02a392a0 | 2406 | ftrace_bug_type = FTRACE_BUG_UPDATE; |
08f6fba5 | 2407 | return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr); |
5072c59f SR |
2408 | } |
2409 | ||
c88fd863 | 2410 | return -1; /* unknow ftrace bug */ |
5072c59f SR |
2411 | } |
2412 | ||
e4f5d544 | 2413 | void __weak ftrace_replace_code(int enable) |
3c1720f0 | 2414 | { |
3c1720f0 SR |
2415 | struct dyn_ftrace *rec; |
2416 | struct ftrace_page *pg; | |
6a24a244 | 2417 | int failed; |
3c1720f0 | 2418 | |
45a4a237 SR |
2419 | if (unlikely(ftrace_disabled)) |
2420 | return; | |
2421 | ||
265c831c | 2422 | do_for_each_ftrace_rec(pg, rec) { |
546fece4 SRRH |
2423 | |
2424 | if (rec->flags & FTRACE_FL_DISABLED) | |
2425 | continue; | |
2426 | ||
e4f5d544 | 2427 | failed = __ftrace_replace_code(rec, enable); |
fa9d13cf | 2428 | if (failed) { |
4fd3279b | 2429 | ftrace_bug(failed, rec); |
3279ba37 SR |
2430 | /* Stop processing */ |
2431 | return; | |
3c1720f0 | 2432 | } |
265c831c | 2433 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
2434 | } |
2435 | ||
c88fd863 SR |
2436 | struct ftrace_rec_iter { |
2437 | struct ftrace_page *pg; | |
2438 | int index; | |
2439 | }; | |
2440 | ||
2441 | /** | |
2442 | * ftrace_rec_iter_start, start up iterating over traced functions | |
2443 | * | |
2444 | * Returns an iterator handle that is used to iterate over all | |
2445 | * the records that represent address locations where functions | |
2446 | * are traced. | |
2447 | * | |
2448 | * May return NULL if no records are available. | |
2449 | */ | |
2450 | struct ftrace_rec_iter *ftrace_rec_iter_start(void) | |
2451 | { | |
2452 | /* | |
2453 | * We only use a single iterator. | |
2454 | * Protected by the ftrace_lock mutex. | |
2455 | */ | |
2456 | static struct ftrace_rec_iter ftrace_rec_iter; | |
2457 | struct ftrace_rec_iter *iter = &ftrace_rec_iter; | |
2458 | ||
2459 | iter->pg = ftrace_pages_start; | |
2460 | iter->index = 0; | |
2461 | ||
2462 | /* Could have empty pages */ | |
2463 | while (iter->pg && !iter->pg->index) | |
2464 | iter->pg = iter->pg->next; | |
2465 | ||
2466 | if (!iter->pg) | |
2467 | return NULL; | |
2468 | ||
2469 | return iter; | |
2470 | } | |
2471 | ||
2472 | /** | |
2473 | * ftrace_rec_iter_next, get the next record to process. | |
2474 | * @iter: The handle to the iterator. | |
2475 | * | |
2476 | * Returns the next iterator after the given iterator @iter. | |
2477 | */ | |
2478 | struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter) | |
2479 | { | |
2480 | iter->index++; | |
2481 | ||
2482 | if (iter->index >= iter->pg->index) { | |
2483 | iter->pg = iter->pg->next; | |
2484 | iter->index = 0; | |
2485 | ||
2486 | /* Could have empty pages */ | |
2487 | while (iter->pg && !iter->pg->index) | |
2488 | iter->pg = iter->pg->next; | |
2489 | } | |
2490 | ||
2491 | if (!iter->pg) | |
2492 | return NULL; | |
2493 | ||
2494 | return iter; | |
2495 | } | |
2496 | ||
2497 | /** | |
2498 | * ftrace_rec_iter_record, get the record at the iterator location | |
2499 | * @iter: The current iterator location | |
2500 | * | |
2501 | * Returns the record that the current @iter is at. | |
2502 | */ | |
2503 | struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter) | |
2504 | { | |
2505 | return &iter->pg->records[iter->index]; | |
2506 | } | |
2507 | ||
492a7ea5 | 2508 | static int |
31e88909 | 2509 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 | 2510 | { |
593eb8a2 | 2511 | int ret; |
3c1720f0 | 2512 | |
45a4a237 SR |
2513 | if (unlikely(ftrace_disabled)) |
2514 | return 0; | |
2515 | ||
25aac9dc | 2516 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
593eb8a2 | 2517 | if (ret) { |
02a392a0 | 2518 | ftrace_bug_type = FTRACE_BUG_INIT; |
4fd3279b | 2519 | ftrace_bug(ret, rec); |
492a7ea5 | 2520 | return 0; |
37ad5084 | 2521 | } |
492a7ea5 | 2522 | return 1; |
3c1720f0 SR |
2523 | } |
2524 | ||
000ab691 SR |
2525 | /* |
2526 | * archs can override this function if they must do something | |
2527 | * before the modifying code is performed. | |
2528 | */ | |
2529 | int __weak ftrace_arch_code_modify_prepare(void) | |
2530 | { | |
2531 | return 0; | |
2532 | } | |
2533 | ||
2534 | /* | |
2535 | * archs can override this function if they must do something | |
2536 | * after the modifying code is performed. | |
2537 | */ | |
2538 | int __weak ftrace_arch_code_modify_post_process(void) | |
2539 | { | |
2540 | return 0; | |
2541 | } | |
2542 | ||
8ed3e2cf | 2543 | void ftrace_modify_all_code(int command) |
3d083395 | 2544 | { |
59338f75 | 2545 | int update = command & FTRACE_UPDATE_TRACE_FUNC; |
cd21067f | 2546 | int err = 0; |
59338f75 SRRH |
2547 | |
2548 | /* | |
2549 | * If the ftrace_caller calls a ftrace_ops func directly, | |
2550 | * we need to make sure that it only traces functions it | |
2551 | * expects to trace. When doing the switch of functions, | |
2552 | * we need to update to the ftrace_ops_list_func first | |
2553 | * before the transition between old and new calls are set, | |
2554 | * as the ftrace_ops_list_func will check the ops hashes | |
2555 | * to make sure the ops are having the right functions | |
2556 | * traced. | |
2557 | */ | |
cd21067f PM |
2558 | if (update) { |
2559 | err = ftrace_update_ftrace_func(ftrace_ops_list_func); | |
2560 | if (FTRACE_WARN_ON(err)) | |
2561 | return; | |
2562 | } | |
59338f75 | 2563 | |
8ed3e2cf | 2564 | if (command & FTRACE_UPDATE_CALLS) |
d61f82d0 | 2565 | ftrace_replace_code(1); |
8ed3e2cf | 2566 | else if (command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
2567 | ftrace_replace_code(0); |
2568 | ||
405e1d83 SRRH |
2569 | if (update && ftrace_trace_function != ftrace_ops_list_func) { |
2570 | function_trace_op = set_function_trace_op; | |
2571 | smp_wmb(); | |
2572 | /* If irqs are disabled, we are in stop machine */ | |
2573 | if (!irqs_disabled()) | |
2574 | smp_call_function(ftrace_sync_ipi, NULL, 1); | |
cd21067f PM |
2575 | err = ftrace_update_ftrace_func(ftrace_trace_function); |
2576 | if (FTRACE_WARN_ON(err)) | |
2577 | return; | |
405e1d83 | 2578 | } |
d61f82d0 | 2579 | |
8ed3e2cf | 2580 | if (command & FTRACE_START_FUNC_RET) |
cd21067f | 2581 | err = ftrace_enable_ftrace_graph_caller(); |
8ed3e2cf | 2582 | else if (command & FTRACE_STOP_FUNC_RET) |
cd21067f PM |
2583 | err = ftrace_disable_ftrace_graph_caller(); |
2584 | FTRACE_WARN_ON(err); | |
8ed3e2cf SR |
2585 | } |
2586 | ||
2587 | static int __ftrace_modify_code(void *data) | |
2588 | { | |
2589 | int *command = data; | |
2590 | ||
2591 | ftrace_modify_all_code(*command); | |
5a45cfe1 | 2592 | |
d61f82d0 | 2593 | return 0; |
3d083395 SR |
2594 | } |
2595 | ||
c88fd863 SR |
2596 | /** |
2597 | * ftrace_run_stop_machine, go back to the stop machine method | |
2598 | * @command: The command to tell ftrace what to do | |
2599 | * | |
2600 | * If an arch needs to fall back to the stop machine method, the | |
2601 | * it can call this function. | |
2602 | */ | |
2603 | void ftrace_run_stop_machine(int command) | |
2604 | { | |
2605 | stop_machine(__ftrace_modify_code, &command, NULL); | |
2606 | } | |
2607 | ||
2608 | /** | |
2609 | * arch_ftrace_update_code, modify the code to trace or not trace | |
2610 | * @command: The command that needs to be done | |
2611 | * | |
2612 | * Archs can override this function if it does not need to | |
2613 | * run stop_machine() to modify code. | |
2614 | */ | |
2615 | void __weak arch_ftrace_update_code(int command) | |
2616 | { | |
2617 | ftrace_run_stop_machine(command); | |
2618 | } | |
2619 | ||
e309b41d | 2620 | static void ftrace_run_update_code(int command) |
3d083395 | 2621 | { |
000ab691 SR |
2622 | int ret; |
2623 | ||
2624 | ret = ftrace_arch_code_modify_prepare(); | |
2625 | FTRACE_WARN_ON(ret); | |
2626 | if (ret) | |
2627 | return; | |
2628 | ||
c88fd863 SR |
2629 | /* |
2630 | * By default we use stop_machine() to modify the code. | |
2631 | * But archs can do what ever they want as long as it | |
2632 | * is safe. The stop_machine() is the safest, but also | |
2633 | * produces the most overhead. | |
2634 | */ | |
2635 | arch_ftrace_update_code(command); | |
2636 | ||
000ab691 SR |
2637 | ret = ftrace_arch_code_modify_post_process(); |
2638 | FTRACE_WARN_ON(ret); | |
3d083395 SR |
2639 | } |
2640 | ||
8252ecf3 | 2641 | static void ftrace_run_modify_code(struct ftrace_ops *ops, int command, |
7485058e | 2642 | struct ftrace_ops_hash *old_hash) |
e1effa01 SRRH |
2643 | { |
2644 | ops->flags |= FTRACE_OPS_FL_MODIFYING; | |
7485058e SRRH |
2645 | ops->old_hash.filter_hash = old_hash->filter_hash; |
2646 | ops->old_hash.notrace_hash = old_hash->notrace_hash; | |
e1effa01 | 2647 | ftrace_run_update_code(command); |
8252ecf3 | 2648 | ops->old_hash.filter_hash = NULL; |
7485058e | 2649 | ops->old_hash.notrace_hash = NULL; |
e1effa01 SRRH |
2650 | ops->flags &= ~FTRACE_OPS_FL_MODIFYING; |
2651 | } | |
2652 | ||
d61f82d0 | 2653 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 2654 | static int ftrace_start_up; |
df4fc315 | 2655 | |
12cce594 SRRH |
2656 | void __weak arch_ftrace_trampoline_free(struct ftrace_ops *ops) |
2657 | { | |
2658 | } | |
2659 | ||
ba27f2bc | 2660 | static void per_cpu_ops_free(struct ftrace_ops *ops) |
db0fbadc JS |
2661 | { |
2662 | free_percpu(ops->disabled); | |
2663 | } | |
2664 | ||
df4fc315 SR |
2665 | static void ftrace_startup_enable(int command) |
2666 | { | |
2667 | if (saved_ftrace_func != ftrace_trace_function) { | |
2668 | saved_ftrace_func = ftrace_trace_function; | |
2669 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2670 | } | |
2671 | ||
2672 | if (!command || !ftrace_enabled) | |
2673 | return; | |
2674 | ||
2675 | ftrace_run_update_code(command); | |
2676 | } | |
d61f82d0 | 2677 | |
e1effa01 SRRH |
2678 | static void ftrace_startup_all(int command) |
2679 | { | |
2680 | update_all_ops = true; | |
2681 | ftrace_startup_enable(command); | |
2682 | update_all_ops = false; | |
2683 | } | |
2684 | ||
a1cd6173 | 2685 | static int ftrace_startup(struct ftrace_ops *ops, int command) |
3d083395 | 2686 | { |
8a56d776 | 2687 | int ret; |
b848914c | 2688 | |
4eebcc81 | 2689 | if (unlikely(ftrace_disabled)) |
a1cd6173 | 2690 | return -ENODEV; |
4eebcc81 | 2691 | |
8a56d776 SRRH |
2692 | ret = __register_ftrace_function(ops); |
2693 | if (ret) | |
2694 | return ret; | |
2695 | ||
60a7ecf4 | 2696 | ftrace_start_up++; |
d61f82d0 | 2697 | |
e1effa01 SRRH |
2698 | /* |
2699 | * Note that ftrace probes uses this to start up | |
2700 | * and modify functions it will probe. But we still | |
2701 | * set the ADDING flag for modification, as probes | |
2702 | * do not have trampolines. If they add them in the | |
2703 | * future, then the probes will need to distinguish | |
2704 | * between adding and updating probes. | |
2705 | */ | |
2706 | ops->flags |= FTRACE_OPS_FL_ENABLED | FTRACE_OPS_FL_ADDING; | |
66209a5b | 2707 | |
f8b8be8a MH |
2708 | ret = ftrace_hash_ipmodify_enable(ops); |
2709 | if (ret < 0) { | |
2710 | /* Rollback registration process */ | |
2711 | __unregister_ftrace_function(ops); | |
2712 | ftrace_start_up--; | |
2713 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; | |
2714 | return ret; | |
2715 | } | |
2716 | ||
7f50d06b JO |
2717 | if (ftrace_hash_rec_enable(ops, 1)) |
2718 | command |= FTRACE_UPDATE_CALLS; | |
ed926f9b | 2719 | |
df4fc315 | 2720 | ftrace_startup_enable(command); |
a1cd6173 | 2721 | |
e1effa01 SRRH |
2722 | ops->flags &= ~FTRACE_OPS_FL_ADDING; |
2723 | ||
a1cd6173 | 2724 | return 0; |
3d083395 SR |
2725 | } |
2726 | ||
8a56d776 | 2727 | static int ftrace_shutdown(struct ftrace_ops *ops, int command) |
3d083395 | 2728 | { |
8a56d776 | 2729 | int ret; |
b848914c | 2730 | |
4eebcc81 | 2731 | if (unlikely(ftrace_disabled)) |
8a56d776 SRRH |
2732 | return -ENODEV; |
2733 | ||
2734 | ret = __unregister_ftrace_function(ops); | |
2735 | if (ret) | |
2736 | return ret; | |
4eebcc81 | 2737 | |
60a7ecf4 | 2738 | ftrace_start_up--; |
9ea1a153 FW |
2739 | /* |
2740 | * Just warn in case of unbalance, no need to kill ftrace, it's not | |
2741 | * critical but the ftrace_call callers may be never nopped again after | |
2742 | * further ftrace uses. | |
2743 | */ | |
2744 | WARN_ON_ONCE(ftrace_start_up < 0); | |
2745 | ||
f8b8be8a MH |
2746 | /* Disabling ipmodify never fails */ |
2747 | ftrace_hash_ipmodify_disable(ops); | |
ed926f9b | 2748 | |
7f50d06b JO |
2749 | if (ftrace_hash_rec_disable(ops, 1)) |
2750 | command |= FTRACE_UPDATE_CALLS; | |
b848914c | 2751 | |
7f50d06b | 2752 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; |
3d083395 | 2753 | |
d61f82d0 SR |
2754 | if (saved_ftrace_func != ftrace_trace_function) { |
2755 | saved_ftrace_func = ftrace_trace_function; | |
2756 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2757 | } | |
3d083395 | 2758 | |
a4c35ed2 SRRH |
2759 | if (!command || !ftrace_enabled) { |
2760 | /* | |
ba27f2bc | 2761 | * If these are per_cpu ops, they still need their |
a4c35ed2 SRRH |
2762 | * per_cpu field freed. Since, function tracing is |
2763 | * not currently active, we can just free them | |
2764 | * without synchronizing all CPUs. | |
2765 | */ | |
ba27f2bc SRRH |
2766 | if (ops->flags & FTRACE_OPS_FL_PER_CPU) |
2767 | per_cpu_ops_free(ops); | |
8a56d776 | 2768 | return 0; |
a4c35ed2 | 2769 | } |
d61f82d0 | 2770 | |
79922b80 SRRH |
2771 | /* |
2772 | * If the ops uses a trampoline, then it needs to be | |
2773 | * tested first on update. | |
2774 | */ | |
e1effa01 | 2775 | ops->flags |= FTRACE_OPS_FL_REMOVING; |
79922b80 SRRH |
2776 | removed_ops = ops; |
2777 | ||
fef5aeee SRRH |
2778 | /* The trampoline logic checks the old hashes */ |
2779 | ops->old_hash.filter_hash = ops->func_hash->filter_hash; | |
2780 | ops->old_hash.notrace_hash = ops->func_hash->notrace_hash; | |
2781 | ||
d61f82d0 | 2782 | ftrace_run_update_code(command); |
a4c35ed2 | 2783 | |
84bde62c SRRH |
2784 | /* |
2785 | * If there's no more ops registered with ftrace, run a | |
2786 | * sanity check to make sure all rec flags are cleared. | |
2787 | */ | |
2788 | if (ftrace_ops_list == &ftrace_list_end) { | |
2789 | struct ftrace_page *pg; | |
2790 | struct dyn_ftrace *rec; | |
2791 | ||
2792 | do_for_each_ftrace_rec(pg, rec) { | |
977c1f9c | 2793 | if (FTRACE_WARN_ON_ONCE(rec->flags & ~FTRACE_FL_DISABLED)) |
84bde62c SRRH |
2794 | pr_warn(" %pS flags:%lx\n", |
2795 | (void *)rec->ip, rec->flags); | |
2796 | } while_for_each_ftrace_rec(); | |
2797 | } | |
2798 | ||
fef5aeee SRRH |
2799 | ops->old_hash.filter_hash = NULL; |
2800 | ops->old_hash.notrace_hash = NULL; | |
2801 | ||
2802 | removed_ops = NULL; | |
e1effa01 | 2803 | ops->flags &= ~FTRACE_OPS_FL_REMOVING; |
79922b80 | 2804 | |
a4c35ed2 SRRH |
2805 | /* |
2806 | * Dynamic ops may be freed, we must make sure that all | |
2807 | * callers are done before leaving this function. | |
ba27f2bc | 2808 | * The same goes for freeing the per_cpu data of the per_cpu |
a4c35ed2 SRRH |
2809 | * ops. |
2810 | * | |
2811 | * Again, normal synchronize_sched() is not good enough. | |
2812 | * We need to do a hard force of sched synchronization. | |
2813 | * This is because we use preempt_disable() to do RCU, but | |
2814 | * the function tracers can be called where RCU is not watching | |
2815 | * (like before user_exit()). We can not rely on the RCU | |
2816 | * infrastructure to do the synchronization, thus we must do it | |
2817 | * ourselves. | |
2818 | */ | |
ba27f2bc | 2819 | if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_PER_CPU)) { |
a4c35ed2 SRRH |
2820 | schedule_on_each_cpu(ftrace_sync); |
2821 | ||
12cce594 SRRH |
2822 | arch_ftrace_trampoline_free(ops); |
2823 | ||
ba27f2bc SRRH |
2824 | if (ops->flags & FTRACE_OPS_FL_PER_CPU) |
2825 | per_cpu_ops_free(ops); | |
a4c35ed2 SRRH |
2826 | } |
2827 | ||
8a56d776 | 2828 | return 0; |
3d083395 SR |
2829 | } |
2830 | ||
e309b41d | 2831 | static void ftrace_startup_sysctl(void) |
b0fc494f | 2832 | { |
1619dc3f PA |
2833 | int command; |
2834 | ||
4eebcc81 SR |
2835 | if (unlikely(ftrace_disabled)) |
2836 | return; | |
2837 | ||
d61f82d0 SR |
2838 | /* Force update next time */ |
2839 | saved_ftrace_func = NULL; | |
60a7ecf4 | 2840 | /* ftrace_start_up is true if we want ftrace running */ |
1619dc3f PA |
2841 | if (ftrace_start_up) { |
2842 | command = FTRACE_UPDATE_CALLS; | |
2843 | if (ftrace_graph_active) | |
2844 | command |= FTRACE_START_FUNC_RET; | |
524a3868 | 2845 | ftrace_startup_enable(command); |
1619dc3f | 2846 | } |
b0fc494f SR |
2847 | } |
2848 | ||
e309b41d | 2849 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 2850 | { |
1619dc3f PA |
2851 | int command; |
2852 | ||
4eebcc81 SR |
2853 | if (unlikely(ftrace_disabled)) |
2854 | return; | |
2855 | ||
60a7ecf4 | 2856 | /* ftrace_start_up is true if ftrace is running */ |
1619dc3f PA |
2857 | if (ftrace_start_up) { |
2858 | command = FTRACE_DISABLE_CALLS; | |
2859 | if (ftrace_graph_active) | |
2860 | command |= FTRACE_STOP_FUNC_RET; | |
2861 | ftrace_run_update_code(command); | |
2862 | } | |
b0fc494f SR |
2863 | } |
2864 | ||
a5a1d1c2 | 2865 | static u64 ftrace_update_time; |
3d083395 SR |
2866 | unsigned long ftrace_update_tot_cnt; |
2867 | ||
8c4f3c3f | 2868 | static inline int ops_traces_mod(struct ftrace_ops *ops) |
f7bc8b61 | 2869 | { |
8c4f3c3f SRRH |
2870 | /* |
2871 | * Filter_hash being empty will default to trace module. | |
2872 | * But notrace hash requires a test of individual module functions. | |
2873 | */ | |
33b7f99c SRRH |
2874 | return ftrace_hash_empty(ops->func_hash->filter_hash) && |
2875 | ftrace_hash_empty(ops->func_hash->notrace_hash); | |
8c4f3c3f SRRH |
2876 | } |
2877 | ||
2878 | /* | |
2879 | * Check if the current ops references the record. | |
2880 | * | |
2881 | * If the ops traces all functions, then it was already accounted for. | |
2882 | * If the ops does not trace the current record function, skip it. | |
2883 | * If the ops ignores the function via notrace filter, skip it. | |
2884 | */ | |
2885 | static inline bool | |
2886 | ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec) | |
2887 | { | |
2888 | /* If ops isn't enabled, ignore it */ | |
2889 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
2890 | return 0; | |
2891 | ||
b7ffffbb | 2892 | /* If ops traces all then it includes this function */ |
8c4f3c3f | 2893 | if (ops_traces_mod(ops)) |
b7ffffbb | 2894 | return 1; |
8c4f3c3f SRRH |
2895 | |
2896 | /* The function must be in the filter */ | |
33b7f99c | 2897 | if (!ftrace_hash_empty(ops->func_hash->filter_hash) && |
2b2c279c | 2898 | !__ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip)) |
8c4f3c3f | 2899 | return 0; |
f7bc8b61 | 2900 | |
8c4f3c3f | 2901 | /* If in notrace hash, we ignore it too */ |
33b7f99c | 2902 | if (ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip)) |
8c4f3c3f SRRH |
2903 | return 0; |
2904 | ||
2905 | return 1; | |
2906 | } | |
2907 | ||
1dc43cf0 | 2908 | static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs) |
3d083395 | 2909 | { |
85ae32ae | 2910 | struct ftrace_page *pg; |
e94142a6 | 2911 | struct dyn_ftrace *p; |
a5a1d1c2 | 2912 | u64 start, stop; |
1dc43cf0 | 2913 | unsigned long update_cnt = 0; |
b7ffffbb | 2914 | unsigned long rec_flags = 0; |
85ae32ae | 2915 | int i; |
f7bc8b61 | 2916 | |
b7ffffbb SRRH |
2917 | start = ftrace_now(raw_smp_processor_id()); |
2918 | ||
f7bc8b61 | 2919 | /* |
b7ffffbb SRRH |
2920 | * When a module is loaded, this function is called to convert |
2921 | * the calls to mcount in its text to nops, and also to create | |
2922 | * an entry in the ftrace data. Now, if ftrace is activated | |
2923 | * after this call, but before the module sets its text to | |
2924 | * read-only, the modification of enabling ftrace can fail if | |
2925 | * the read-only is done while ftrace is converting the calls. | |
2926 | * To prevent this, the module's records are set as disabled | |
2927 | * and will be enabled after the call to set the module's text | |
2928 | * to read-only. | |
f7bc8b61 | 2929 | */ |
b7ffffbb SRRH |
2930 | if (mod) |
2931 | rec_flags |= FTRACE_FL_DISABLED; | |
3d083395 | 2932 | |
1dc43cf0 | 2933 | for (pg = new_pgs; pg; pg = pg->next) { |
3d083395 | 2934 | |
85ae32ae | 2935 | for (i = 0; i < pg->index; i++) { |
8c4f3c3f | 2936 | |
85ae32ae SR |
2937 | /* If something went wrong, bail without enabling anything */ |
2938 | if (unlikely(ftrace_disabled)) | |
2939 | return -1; | |
f22f9a89 | 2940 | |
85ae32ae | 2941 | p = &pg->records[i]; |
b7ffffbb | 2942 | p->flags = rec_flags; |
f22f9a89 | 2943 | |
85ae32ae SR |
2944 | /* |
2945 | * Do the initial record conversion from mcount jump | |
2946 | * to the NOP instructions. | |
2947 | */ | |
2948 | if (!ftrace_code_disable(mod, p)) | |
2949 | break; | |
5cb084bb | 2950 | |
1dc43cf0 | 2951 | update_cnt++; |
5cb084bb | 2952 | } |
3d083395 SR |
2953 | } |
2954 | ||
750ed1a4 | 2955 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 | 2956 | ftrace_update_time = stop - start; |
1dc43cf0 | 2957 | ftrace_update_tot_cnt += update_cnt; |
3d083395 | 2958 | |
16444a8a ACM |
2959 | return 0; |
2960 | } | |
2961 | ||
a7900875 | 2962 | static int ftrace_allocate_records(struct ftrace_page *pg, int count) |
3c1720f0 | 2963 | { |
a7900875 | 2964 | int order; |
3c1720f0 | 2965 | int cnt; |
3c1720f0 | 2966 | |
a7900875 SR |
2967 | if (WARN_ON(!count)) |
2968 | return -EINVAL; | |
2969 | ||
2970 | order = get_count_order(DIV_ROUND_UP(count, ENTRIES_PER_PAGE)); | |
3c1720f0 SR |
2971 | |
2972 | /* | |
a7900875 SR |
2973 | * We want to fill as much as possible. No more than a page |
2974 | * may be empty. | |
3c1720f0 | 2975 | */ |
a7900875 SR |
2976 | while ((PAGE_SIZE << order) / ENTRY_SIZE >= count + ENTRIES_PER_PAGE) |
2977 | order--; | |
3c1720f0 | 2978 | |
a7900875 SR |
2979 | again: |
2980 | pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); | |
3c1720f0 | 2981 | |
a7900875 SR |
2982 | if (!pg->records) { |
2983 | /* if we can't allocate this size, try something smaller */ | |
2984 | if (!order) | |
2985 | return -ENOMEM; | |
2986 | order >>= 1; | |
2987 | goto again; | |
2988 | } | |
3c1720f0 | 2989 | |
a7900875 SR |
2990 | cnt = (PAGE_SIZE << order) / ENTRY_SIZE; |
2991 | pg->size = cnt; | |
3c1720f0 | 2992 | |
a7900875 SR |
2993 | if (cnt > count) |
2994 | cnt = count; | |
2995 | ||
2996 | return cnt; | |
2997 | } | |
2998 | ||
2999 | static struct ftrace_page * | |
3000 | ftrace_allocate_pages(unsigned long num_to_init) | |
3001 | { | |
3002 | struct ftrace_page *start_pg; | |
3003 | struct ftrace_page *pg; | |
3004 | int order; | |
3005 | int cnt; | |
3006 | ||
3007 | if (!num_to_init) | |
3008 | return 0; | |
3009 | ||
3010 | start_pg = pg = kzalloc(sizeof(*pg), GFP_KERNEL); | |
3011 | if (!pg) | |
3012 | return NULL; | |
3013 | ||
3014 | /* | |
3015 | * Try to allocate as much as possible in one continues | |
3016 | * location that fills in all of the space. We want to | |
3017 | * waste as little space as possible. | |
3018 | */ | |
3019 | for (;;) { | |
3020 | cnt = ftrace_allocate_records(pg, num_to_init); | |
3021 | if (cnt < 0) | |
3022 | goto free_pages; | |
3023 | ||
3024 | num_to_init -= cnt; | |
3025 | if (!num_to_init) | |
3c1720f0 SR |
3026 | break; |
3027 | ||
a7900875 SR |
3028 | pg->next = kzalloc(sizeof(*pg), GFP_KERNEL); |
3029 | if (!pg->next) | |
3030 | goto free_pages; | |
3031 | ||
3c1720f0 SR |
3032 | pg = pg->next; |
3033 | } | |
3034 | ||
a7900875 SR |
3035 | return start_pg; |
3036 | ||
3037 | free_pages: | |
1f61be00 NK |
3038 | pg = start_pg; |
3039 | while (pg) { | |
a7900875 SR |
3040 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); |
3041 | free_pages((unsigned long)pg->records, order); | |
3042 | start_pg = pg->next; | |
3043 | kfree(pg); | |
3044 | pg = start_pg; | |
3045 | } | |
3046 | pr_info("ftrace: FAILED to allocate memory for functions\n"); | |
3047 | return NULL; | |
3048 | } | |
3049 | ||
5072c59f SR |
3050 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ |
3051 | ||
3052 | struct ftrace_iterator { | |
98c4fd04 | 3053 | loff_t pos; |
4aeb6967 SR |
3054 | loff_t func_pos; |
3055 | struct ftrace_page *pg; | |
3056 | struct dyn_ftrace *func; | |
3057 | struct ftrace_func_probe *probe; | |
3058 | struct trace_parser parser; | |
1cf41dd7 | 3059 | struct ftrace_hash *hash; |
33dc9b12 | 3060 | struct ftrace_ops *ops; |
4aeb6967 SR |
3061 | int hidx; |
3062 | int idx; | |
3063 | unsigned flags; | |
5072c59f SR |
3064 | }; |
3065 | ||
8fc0c701 | 3066 | static void * |
4aeb6967 | 3067 | t_hash_next(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
3068 | { |
3069 | struct ftrace_iterator *iter = m->private; | |
4aeb6967 | 3070 | struct hlist_node *hnd = NULL; |
8fc0c701 SR |
3071 | struct hlist_head *hhd; |
3072 | ||
8fc0c701 | 3073 | (*pos)++; |
98c4fd04 | 3074 | iter->pos = *pos; |
8fc0c701 | 3075 | |
4aeb6967 SR |
3076 | if (iter->probe) |
3077 | hnd = &iter->probe->node; | |
8fc0c701 SR |
3078 | retry: |
3079 | if (iter->hidx >= FTRACE_FUNC_HASHSIZE) | |
3080 | return NULL; | |
3081 | ||
3082 | hhd = &ftrace_func_hash[iter->hidx]; | |
3083 | ||
3084 | if (hlist_empty(hhd)) { | |
3085 | iter->hidx++; | |
3086 | hnd = NULL; | |
3087 | goto retry; | |
3088 | } | |
3089 | ||
3090 | if (!hnd) | |
3091 | hnd = hhd->first; | |
3092 | else { | |
3093 | hnd = hnd->next; | |
3094 | if (!hnd) { | |
3095 | iter->hidx++; | |
3096 | goto retry; | |
3097 | } | |
3098 | } | |
3099 | ||
4aeb6967 SR |
3100 | if (WARN_ON_ONCE(!hnd)) |
3101 | return NULL; | |
3102 | ||
3103 | iter->probe = hlist_entry(hnd, struct ftrace_func_probe, node); | |
3104 | ||
3105 | return iter; | |
8fc0c701 SR |
3106 | } |
3107 | ||
3108 | static void *t_hash_start(struct seq_file *m, loff_t *pos) | |
3109 | { | |
3110 | struct ftrace_iterator *iter = m->private; | |
3111 | void *p = NULL; | |
d82d6244 LZ |
3112 | loff_t l; |
3113 | ||
69a3083c SR |
3114 | if (!(iter->flags & FTRACE_ITER_DO_HASH)) |
3115 | return NULL; | |
3116 | ||
2bccfffd SR |
3117 | if (iter->func_pos > *pos) |
3118 | return NULL; | |
8fc0c701 | 3119 | |
d82d6244 | 3120 | iter->hidx = 0; |
2bccfffd | 3121 | for (l = 0; l <= (*pos - iter->func_pos); ) { |
4aeb6967 | 3122 | p = t_hash_next(m, &l); |
d82d6244 LZ |
3123 | if (!p) |
3124 | break; | |
3125 | } | |
4aeb6967 SR |
3126 | if (!p) |
3127 | return NULL; | |
3128 | ||
98c4fd04 SR |
3129 | /* Only set this if we have an item */ |
3130 | iter->flags |= FTRACE_ITER_HASH; | |
3131 | ||
4aeb6967 | 3132 | return iter; |
8fc0c701 SR |
3133 | } |
3134 | ||
4aeb6967 SR |
3135 | static int |
3136 | t_hash_show(struct seq_file *m, struct ftrace_iterator *iter) | |
8fc0c701 | 3137 | { |
b6887d79 | 3138 | struct ftrace_func_probe *rec; |
8fc0c701 | 3139 | |
4aeb6967 SR |
3140 | rec = iter->probe; |
3141 | if (WARN_ON_ONCE(!rec)) | |
3142 | return -EIO; | |
8fc0c701 | 3143 | |
809dcf29 SR |
3144 | if (rec->ops->print) |
3145 | return rec->ops->print(m, rec->ip, rec->ops, rec->data); | |
3146 | ||
b375a11a | 3147 | seq_printf(m, "%ps:%ps", (void *)rec->ip, (void *)rec->ops->func); |
8fc0c701 SR |
3148 | |
3149 | if (rec->data) | |
3150 | seq_printf(m, ":%p", rec->data); | |
3151 | seq_putc(m, '\n'); | |
3152 | ||
3153 | return 0; | |
3154 | } | |
3155 | ||
e309b41d | 3156 | static void * |
5072c59f SR |
3157 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3158 | { | |
3159 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 3160 | struct ftrace_ops *ops = iter->ops; |
5072c59f SR |
3161 | struct dyn_ftrace *rec = NULL; |
3162 | ||
45a4a237 SR |
3163 | if (unlikely(ftrace_disabled)) |
3164 | return NULL; | |
3165 | ||
8fc0c701 | 3166 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 3167 | return t_hash_next(m, pos); |
8fc0c701 | 3168 | |
5072c59f | 3169 | (*pos)++; |
1106b699 | 3170 | iter->pos = iter->func_pos = *pos; |
5072c59f | 3171 | |
0c75a3ed | 3172 | if (iter->flags & FTRACE_ITER_PRINTALL) |
57c072c7 | 3173 | return t_hash_start(m, pos); |
0c75a3ed | 3174 | |
5072c59f SR |
3175 | retry: |
3176 | if (iter->idx >= iter->pg->index) { | |
3177 | if (iter->pg->next) { | |
3178 | iter->pg = iter->pg->next; | |
3179 | iter->idx = 0; | |
3180 | goto retry; | |
3181 | } | |
3182 | } else { | |
3183 | rec = &iter->pg->records[iter->idx++]; | |
32082309 | 3184 | if (((iter->flags & FTRACE_ITER_FILTER) && |
33b7f99c | 3185 | !(ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip))) || |
0183fb1c | 3186 | |
41c52c0d | 3187 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
33b7f99c | 3188 | !ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip)) || |
647bcd03 SR |
3189 | |
3190 | ((iter->flags & FTRACE_ITER_ENABLED) && | |
23ea9c4d | 3191 | !(rec->flags & FTRACE_FL_ENABLED))) { |
647bcd03 | 3192 | |
5072c59f SR |
3193 | rec = NULL; |
3194 | goto retry; | |
3195 | } | |
3196 | } | |
3197 | ||
4aeb6967 | 3198 | if (!rec) |
57c072c7 | 3199 | return t_hash_start(m, pos); |
4aeb6967 SR |
3200 | |
3201 | iter->func = rec; | |
3202 | ||
3203 | return iter; | |
5072c59f SR |
3204 | } |
3205 | ||
98c4fd04 SR |
3206 | static void reset_iter_read(struct ftrace_iterator *iter) |
3207 | { | |
3208 | iter->pos = 0; | |
3209 | iter->func_pos = 0; | |
70f77b3f | 3210 | iter->flags &= ~(FTRACE_ITER_PRINTALL | FTRACE_ITER_HASH); |
5072c59f SR |
3211 | } |
3212 | ||
3213 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3214 | { | |
3215 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 3216 | struct ftrace_ops *ops = iter->ops; |
5072c59f | 3217 | void *p = NULL; |
694ce0a5 | 3218 | loff_t l; |
5072c59f | 3219 | |
8fc0c701 | 3220 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
3221 | |
3222 | if (unlikely(ftrace_disabled)) | |
3223 | return NULL; | |
3224 | ||
98c4fd04 SR |
3225 | /* |
3226 | * If an lseek was done, then reset and start from beginning. | |
3227 | */ | |
3228 | if (*pos < iter->pos) | |
3229 | reset_iter_read(iter); | |
3230 | ||
0c75a3ed SR |
3231 | /* |
3232 | * For set_ftrace_filter reading, if we have the filter | |
3233 | * off, we can short cut and just print out that all | |
3234 | * functions are enabled. | |
3235 | */ | |
8c006cf7 | 3236 | if ((iter->flags & FTRACE_ITER_FILTER && |
33b7f99c | 3237 | ftrace_hash_empty(ops->func_hash->filter_hash)) || |
8c006cf7 | 3238 | (iter->flags & FTRACE_ITER_NOTRACE && |
33b7f99c | 3239 | ftrace_hash_empty(ops->func_hash->notrace_hash))) { |
0c75a3ed | 3240 | if (*pos > 0) |
8fc0c701 | 3241 | return t_hash_start(m, pos); |
0c75a3ed | 3242 | iter->flags |= FTRACE_ITER_PRINTALL; |
df091625 CW |
3243 | /* reset in case of seek/pread */ |
3244 | iter->flags &= ~FTRACE_ITER_HASH; | |
0c75a3ed SR |
3245 | return iter; |
3246 | } | |
3247 | ||
8fc0c701 SR |
3248 | if (iter->flags & FTRACE_ITER_HASH) |
3249 | return t_hash_start(m, pos); | |
3250 | ||
98c4fd04 SR |
3251 | /* |
3252 | * Unfortunately, we need to restart at ftrace_pages_start | |
3253 | * every time we let go of the ftrace_mutex. This is because | |
3254 | * those pointers can change without the lock. | |
3255 | */ | |
694ce0a5 LZ |
3256 | iter->pg = ftrace_pages_start; |
3257 | iter->idx = 0; | |
3258 | for (l = 0; l <= *pos; ) { | |
3259 | p = t_next(m, p, &l); | |
3260 | if (!p) | |
3261 | break; | |
50cdaf08 | 3262 | } |
5821e1b7 | 3263 | |
69a3083c SR |
3264 | if (!p) |
3265 | return t_hash_start(m, pos); | |
4aeb6967 SR |
3266 | |
3267 | return iter; | |
5072c59f SR |
3268 | } |
3269 | ||
3270 | static void t_stop(struct seq_file *m, void *p) | |
3271 | { | |
8fc0c701 | 3272 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
3273 | } |
3274 | ||
15d5b02c SRRH |
3275 | void * __weak |
3276 | arch_ftrace_trampoline_func(struct ftrace_ops *ops, struct dyn_ftrace *rec) | |
3277 | { | |
3278 | return NULL; | |
3279 | } | |
3280 | ||
3281 | static void add_trampoline_func(struct seq_file *m, struct ftrace_ops *ops, | |
3282 | struct dyn_ftrace *rec) | |
3283 | { | |
3284 | void *ptr; | |
3285 | ||
3286 | ptr = arch_ftrace_trampoline_func(ops, rec); | |
3287 | if (ptr) | |
3288 | seq_printf(m, " ->%pS", ptr); | |
3289 | } | |
3290 | ||
5072c59f SR |
3291 | static int t_show(struct seq_file *m, void *v) |
3292 | { | |
0c75a3ed | 3293 | struct ftrace_iterator *iter = m->private; |
4aeb6967 | 3294 | struct dyn_ftrace *rec; |
5072c59f | 3295 | |
8fc0c701 | 3296 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 3297 | return t_hash_show(m, iter); |
8fc0c701 | 3298 | |
0c75a3ed | 3299 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
8c006cf7 | 3300 | if (iter->flags & FTRACE_ITER_NOTRACE) |
fa6f0cc7 | 3301 | seq_puts(m, "#### no functions disabled ####\n"); |
8c006cf7 | 3302 | else |
fa6f0cc7 | 3303 | seq_puts(m, "#### all functions enabled ####\n"); |
0c75a3ed SR |
3304 | return 0; |
3305 | } | |
3306 | ||
4aeb6967 SR |
3307 | rec = iter->func; |
3308 | ||
5072c59f SR |
3309 | if (!rec) |
3310 | return 0; | |
3311 | ||
647bcd03 | 3312 | seq_printf(m, "%ps", (void *)rec->ip); |
9674b2fa | 3313 | if (iter->flags & FTRACE_ITER_ENABLED) { |
030f4e1c | 3314 | struct ftrace_ops *ops; |
15d5b02c | 3315 | |
f8b8be8a | 3316 | seq_printf(m, " (%ld)%s%s", |
0376bde1 | 3317 | ftrace_rec_count(rec), |
f8b8be8a MH |
3318 | rec->flags & FTRACE_FL_REGS ? " R" : " ", |
3319 | rec->flags & FTRACE_FL_IPMODIFY ? " I" : " "); | |
9674b2fa | 3320 | if (rec->flags & FTRACE_FL_TRAMP_EN) { |
5fecaa04 | 3321 | ops = ftrace_find_tramp_ops_any(rec); |
39daa7b9 SRRH |
3322 | if (ops) { |
3323 | do { | |
3324 | seq_printf(m, "\ttramp: %pS (%pS)", | |
3325 | (void *)ops->trampoline, | |
3326 | (void *)ops->func); | |
030f4e1c | 3327 | add_trampoline_func(m, ops, rec); |
39daa7b9 SRRH |
3328 | ops = ftrace_find_tramp_ops_next(rec, ops); |
3329 | } while (ops); | |
3330 | } else | |
fa6f0cc7 | 3331 | seq_puts(m, "\ttramp: ERROR!"); |
030f4e1c SRRH |
3332 | } else { |
3333 | add_trampoline_func(m, NULL, rec); | |
9674b2fa SRRH |
3334 | } |
3335 | } | |
3336 | ||
fa6f0cc7 | 3337 | seq_putc(m, '\n'); |
5072c59f SR |
3338 | |
3339 | return 0; | |
3340 | } | |
3341 | ||
88e9d34c | 3342 | static const struct seq_operations show_ftrace_seq_ops = { |
5072c59f SR |
3343 | .start = t_start, |
3344 | .next = t_next, | |
3345 | .stop = t_stop, | |
3346 | .show = t_show, | |
3347 | }; | |
3348 | ||
e309b41d | 3349 | static int |
5072c59f SR |
3350 | ftrace_avail_open(struct inode *inode, struct file *file) |
3351 | { | |
3352 | struct ftrace_iterator *iter; | |
5072c59f | 3353 | |
4eebcc81 SR |
3354 | if (unlikely(ftrace_disabled)) |
3355 | return -ENODEV; | |
3356 | ||
50e18b94 JO |
3357 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
3358 | if (iter) { | |
3359 | iter->pg = ftrace_pages_start; | |
3360 | iter->ops = &global_ops; | |
4bf39a94 | 3361 | } |
5072c59f | 3362 | |
50e18b94 | 3363 | return iter ? 0 : -ENOMEM; |
5072c59f SR |
3364 | } |
3365 | ||
647bcd03 SR |
3366 | static int |
3367 | ftrace_enabled_open(struct inode *inode, struct file *file) | |
3368 | { | |
3369 | struct ftrace_iterator *iter; | |
647bcd03 | 3370 | |
50e18b94 JO |
3371 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
3372 | if (iter) { | |
3373 | iter->pg = ftrace_pages_start; | |
3374 | iter->flags = FTRACE_ITER_ENABLED; | |
3375 | iter->ops = &global_ops; | |
647bcd03 SR |
3376 | } |
3377 | ||
50e18b94 | 3378 | return iter ? 0 : -ENOMEM; |
647bcd03 SR |
3379 | } |
3380 | ||
fc13cb0c SR |
3381 | /** |
3382 | * ftrace_regex_open - initialize function tracer filter files | |
3383 | * @ops: The ftrace_ops that hold the hash filters | |
3384 | * @flag: The type of filter to process | |
3385 | * @inode: The inode, usually passed in to your open routine | |
3386 | * @file: The file, usually passed in to your open routine | |
3387 | * | |
3388 | * ftrace_regex_open() initializes the filter files for the | |
3389 | * @ops. Depending on @flag it may process the filter hash or | |
3390 | * the notrace hash of @ops. With this called from the open | |
3391 | * routine, you can use ftrace_filter_write() for the write | |
3392 | * routine if @flag has FTRACE_ITER_FILTER set, or | |
3393 | * ftrace_notrace_write() if @flag has FTRACE_ITER_NOTRACE set. | |
098c879e | 3394 | * tracing_lseek() should be used as the lseek routine, and |
fc13cb0c SR |
3395 | * release must call ftrace_regex_release(). |
3396 | */ | |
3397 | int | |
f45948e8 | 3398 | ftrace_regex_open(struct ftrace_ops *ops, int flag, |
1cf41dd7 | 3399 | struct inode *inode, struct file *file) |
5072c59f SR |
3400 | { |
3401 | struct ftrace_iterator *iter; | |
f45948e8 | 3402 | struct ftrace_hash *hash; |
5072c59f SR |
3403 | int ret = 0; |
3404 | ||
f04f24fb MH |
3405 | ftrace_ops_init(ops); |
3406 | ||
4eebcc81 SR |
3407 | if (unlikely(ftrace_disabled)) |
3408 | return -ENODEV; | |
3409 | ||
5072c59f SR |
3410 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
3411 | if (!iter) | |
3412 | return -ENOMEM; | |
3413 | ||
689fd8b6 | 3414 | if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) { |
3415 | kfree(iter); | |
3416 | return -ENOMEM; | |
3417 | } | |
3418 | ||
3f2367ba MH |
3419 | iter->ops = ops; |
3420 | iter->flags = flag; | |
3421 | ||
33b7f99c | 3422 | mutex_lock(&ops->func_hash->regex_lock); |
3f2367ba | 3423 | |
f45948e8 | 3424 | if (flag & FTRACE_ITER_NOTRACE) |
33b7f99c | 3425 | hash = ops->func_hash->notrace_hash; |
f45948e8 | 3426 | else |
33b7f99c | 3427 | hash = ops->func_hash->filter_hash; |
f45948e8 | 3428 | |
33dc9b12 | 3429 | if (file->f_mode & FMODE_WRITE) { |
ef2fbe16 NK |
3430 | const int size_bits = FTRACE_HASH_DEFAULT_BITS; |
3431 | ||
3432 | if (file->f_flags & O_TRUNC) | |
3433 | iter->hash = alloc_ftrace_hash(size_bits); | |
3434 | else | |
3435 | iter->hash = alloc_and_copy_ftrace_hash(size_bits, hash); | |
3436 | ||
33dc9b12 SR |
3437 | if (!iter->hash) { |
3438 | trace_parser_put(&iter->parser); | |
3439 | kfree(iter); | |
3f2367ba MH |
3440 | ret = -ENOMEM; |
3441 | goto out_unlock; | |
33dc9b12 SR |
3442 | } |
3443 | } | |
1cf41dd7 | 3444 | |
5072c59f SR |
3445 | if (file->f_mode & FMODE_READ) { |
3446 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
3447 | |
3448 | ret = seq_open(file, &show_ftrace_seq_ops); | |
3449 | if (!ret) { | |
3450 | struct seq_file *m = file->private_data; | |
3451 | m->private = iter; | |
79fe249c | 3452 | } else { |
33dc9b12 SR |
3453 | /* Failed */ |
3454 | free_ftrace_hash(iter->hash); | |
79fe249c | 3455 | trace_parser_put(&iter->parser); |
5072c59f | 3456 | kfree(iter); |
79fe249c | 3457 | } |
5072c59f SR |
3458 | } else |
3459 | file->private_data = iter; | |
3f2367ba MH |
3460 | |
3461 | out_unlock: | |
33b7f99c | 3462 | mutex_unlock(&ops->func_hash->regex_lock); |
5072c59f SR |
3463 | |
3464 | return ret; | |
3465 | } | |
3466 | ||
41c52c0d SR |
3467 | static int |
3468 | ftrace_filter_open(struct inode *inode, struct file *file) | |
3469 | { | |
e3b3e2e8 SRRH |
3470 | struct ftrace_ops *ops = inode->i_private; |
3471 | ||
3472 | return ftrace_regex_open(ops, | |
69a3083c SR |
3473 | FTRACE_ITER_FILTER | FTRACE_ITER_DO_HASH, |
3474 | inode, file); | |
41c52c0d SR |
3475 | } |
3476 | ||
3477 | static int | |
3478 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
3479 | { | |
e3b3e2e8 SRRH |
3480 | struct ftrace_ops *ops = inode->i_private; |
3481 | ||
3482 | return ftrace_regex_open(ops, FTRACE_ITER_NOTRACE, | |
1cf41dd7 | 3483 | inode, file); |
41c52c0d SR |
3484 | } |
3485 | ||
3ba00929 DS |
3486 | /* Type for quick search ftrace basic regexes (globs) from filter_parse_regex */ |
3487 | struct ftrace_glob { | |
3488 | char *search; | |
3489 | unsigned len; | |
3490 | int type; | |
3491 | }; | |
3492 | ||
7132e2d6 TJB |
3493 | /* |
3494 | * If symbols in an architecture don't correspond exactly to the user-visible | |
3495 | * name of what they represent, it is possible to define this function to | |
3496 | * perform the necessary adjustments. | |
3497 | */ | |
3498 | char * __weak arch_ftrace_match_adjust(char *str, const char *search) | |
3499 | { | |
3500 | return str; | |
3501 | } | |
3502 | ||
3ba00929 | 3503 | static int ftrace_match(char *str, struct ftrace_glob *g) |
9f4801e3 | 3504 | { |
9f4801e3 | 3505 | int matched = 0; |
751e9983 | 3506 | int slen; |
9f4801e3 | 3507 | |
7132e2d6 TJB |
3508 | str = arch_ftrace_match_adjust(str, g->search); |
3509 | ||
3ba00929 | 3510 | switch (g->type) { |
9f4801e3 | 3511 | case MATCH_FULL: |
3ba00929 | 3512 | if (strcmp(str, g->search) == 0) |
9f4801e3 SR |
3513 | matched = 1; |
3514 | break; | |
3515 | case MATCH_FRONT_ONLY: | |
3ba00929 | 3516 | if (strncmp(str, g->search, g->len) == 0) |
9f4801e3 SR |
3517 | matched = 1; |
3518 | break; | |
3519 | case MATCH_MIDDLE_ONLY: | |
3ba00929 | 3520 | if (strstr(str, g->search)) |
9f4801e3 SR |
3521 | matched = 1; |
3522 | break; | |
3523 | case MATCH_END_ONLY: | |
751e9983 | 3524 | slen = strlen(str); |
3ba00929 DS |
3525 | if (slen >= g->len && |
3526 | memcmp(str + slen - g->len, g->search, g->len) == 0) | |
9f4801e3 SR |
3527 | matched = 1; |
3528 | break; | |
60f1d5e3 MH |
3529 | case MATCH_GLOB: |
3530 | if (glob_match(g->search, str)) | |
3531 | matched = 1; | |
3532 | break; | |
9f4801e3 SR |
3533 | } |
3534 | ||
3535 | return matched; | |
3536 | } | |
3537 | ||
b448c4e3 | 3538 | static int |
f0a3b154 | 3539 | enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int clear_filter) |
996e87be | 3540 | { |
b448c4e3 | 3541 | struct ftrace_func_entry *entry; |
b448c4e3 SR |
3542 | int ret = 0; |
3543 | ||
1cf41dd7 | 3544 | entry = ftrace_lookup_ip(hash, rec->ip); |
f0a3b154 | 3545 | if (clear_filter) { |
1cf41dd7 SR |
3546 | /* Do nothing if it doesn't exist */ |
3547 | if (!entry) | |
3548 | return 0; | |
b448c4e3 | 3549 | |
33dc9b12 | 3550 | free_hash_entry(hash, entry); |
1cf41dd7 SR |
3551 | } else { |
3552 | /* Do nothing if it exists */ | |
3553 | if (entry) | |
3554 | return 0; | |
b448c4e3 | 3555 | |
1cf41dd7 | 3556 | ret = add_hash_entry(hash, rec->ip); |
b448c4e3 SR |
3557 | } |
3558 | return ret; | |
996e87be SR |
3559 | } |
3560 | ||
64e7c440 | 3561 | static int |
0b507e1e DS |
3562 | ftrace_match_record(struct dyn_ftrace *rec, struct ftrace_glob *func_g, |
3563 | struct ftrace_glob *mod_g, int exclude_mod) | |
64e7c440 SR |
3564 | { |
3565 | char str[KSYM_SYMBOL_LEN]; | |
b9df92d2 SR |
3566 | char *modname; |
3567 | ||
3568 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); | |
3569 | ||
0b507e1e DS |
3570 | if (mod_g) { |
3571 | int mod_matches = (modname) ? ftrace_match(modname, mod_g) : 0; | |
3572 | ||
3573 | /* blank module name to match all modules */ | |
3574 | if (!mod_g->len) { | |
3575 | /* blank module globbing: modname xor exclude_mod */ | |
3576 | if ((!exclude_mod) != (!modname)) | |
3577 | goto func_match; | |
3578 | return 0; | |
3579 | } | |
3580 | ||
3581 | /* not matching the module */ | |
3582 | if (!modname || !mod_matches) { | |
3583 | if (exclude_mod) | |
3584 | goto func_match; | |
3585 | else | |
3586 | return 0; | |
3587 | } | |
3588 | ||
3589 | if (mod_matches && exclude_mod) | |
b9df92d2 SR |
3590 | return 0; |
3591 | ||
0b507e1e | 3592 | func_match: |
b9df92d2 | 3593 | /* blank search means to match all funcs in the mod */ |
3ba00929 | 3594 | if (!func_g->len) |
b9df92d2 SR |
3595 | return 1; |
3596 | } | |
64e7c440 | 3597 | |
3ba00929 | 3598 | return ftrace_match(str, func_g); |
64e7c440 SR |
3599 | } |
3600 | ||
1cf41dd7 | 3601 | static int |
3ba00929 | 3602 | match_records(struct ftrace_hash *hash, char *func, int len, char *mod) |
9f4801e3 | 3603 | { |
9f4801e3 SR |
3604 | struct ftrace_page *pg; |
3605 | struct dyn_ftrace *rec; | |
3ba00929 | 3606 | struct ftrace_glob func_g = { .type = MATCH_FULL }; |
0b507e1e DS |
3607 | struct ftrace_glob mod_g = { .type = MATCH_FULL }; |
3608 | struct ftrace_glob *mod_match = (mod) ? &mod_g : NULL; | |
3609 | int exclude_mod = 0; | |
311d16da | 3610 | int found = 0; |
b448c4e3 | 3611 | int ret; |
f0a3b154 | 3612 | int clear_filter; |
9f4801e3 | 3613 | |
0b507e1e | 3614 | if (func) { |
3ba00929 DS |
3615 | func_g.type = filter_parse_regex(func, len, &func_g.search, |
3616 | &clear_filter); | |
3617 | func_g.len = strlen(func_g.search); | |
b9df92d2 | 3618 | } |
9f4801e3 | 3619 | |
0b507e1e DS |
3620 | if (mod) { |
3621 | mod_g.type = filter_parse_regex(mod, strlen(mod), | |
3622 | &mod_g.search, &exclude_mod); | |
3623 | mod_g.len = strlen(mod_g.search); | |
b9df92d2 | 3624 | } |
9f4801e3 | 3625 | |
52baf119 | 3626 | mutex_lock(&ftrace_lock); |
265c831c | 3627 | |
b9df92d2 SR |
3628 | if (unlikely(ftrace_disabled)) |
3629 | goto out_unlock; | |
9f4801e3 | 3630 | |
265c831c | 3631 | do_for_each_ftrace_rec(pg, rec) { |
546fece4 SRRH |
3632 | |
3633 | if (rec->flags & FTRACE_FL_DISABLED) | |
3634 | continue; | |
3635 | ||
0b507e1e | 3636 | if (ftrace_match_record(rec, &func_g, mod_match, exclude_mod)) { |
f0a3b154 | 3637 | ret = enter_record(hash, rec, clear_filter); |
b448c4e3 SR |
3638 | if (ret < 0) { |
3639 | found = ret; | |
3640 | goto out_unlock; | |
3641 | } | |
311d16da | 3642 | found = 1; |
265c831c SR |
3643 | } |
3644 | } while_for_each_ftrace_rec(); | |
b9df92d2 | 3645 | out_unlock: |
52baf119 | 3646 | mutex_unlock(&ftrace_lock); |
311d16da LZ |
3647 | |
3648 | return found; | |
5072c59f SR |
3649 | } |
3650 | ||
64e7c440 | 3651 | static int |
1cf41dd7 | 3652 | ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) |
64e7c440 | 3653 | { |
f0a3b154 | 3654 | return match_records(hash, buff, len, NULL); |
64e7c440 SR |
3655 | } |
3656 | ||
64e7c440 | 3657 | |
f6180773 SR |
3658 | /* |
3659 | * We register the module command as a template to show others how | |
3660 | * to register the a command as well. | |
3661 | */ | |
3662 | ||
3663 | static int | |
43dd61c9 | 3664 | ftrace_mod_callback(struct ftrace_hash *hash, |
f0a3b154 | 3665 | char *func, char *cmd, char *module, int enable) |
f6180773 | 3666 | { |
5e3949f0 | 3667 | int ret; |
f6180773 SR |
3668 | |
3669 | /* | |
3670 | * cmd == 'mod' because we only registered this func | |
3671 | * for the 'mod' ftrace_func_command. | |
3672 | * But if you register one func with multiple commands, | |
3673 | * you can tell which command was used by the cmd | |
3674 | * parameter. | |
3675 | */ | |
f0a3b154 | 3676 | ret = match_records(hash, func, strlen(func), module); |
b448c4e3 | 3677 | if (!ret) |
5e3949f0 | 3678 | return -EINVAL; |
b448c4e3 SR |
3679 | if (ret < 0) |
3680 | return ret; | |
b448c4e3 | 3681 | return 0; |
f6180773 SR |
3682 | } |
3683 | ||
3684 | static struct ftrace_func_command ftrace_mod_cmd = { | |
3685 | .name = "mod", | |
3686 | .func = ftrace_mod_callback, | |
3687 | }; | |
3688 | ||
3689 | static int __init ftrace_mod_cmd_init(void) | |
3690 | { | |
3691 | return register_ftrace_command(&ftrace_mod_cmd); | |
3692 | } | |
6f415672 | 3693 | core_initcall(ftrace_mod_cmd_init); |
f6180773 | 3694 | |
2f5f6ad9 | 3695 | static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 3696 | struct ftrace_ops *op, struct pt_regs *pt_regs) |
59df055f | 3697 | { |
b6887d79 | 3698 | struct ftrace_func_probe *entry; |
59df055f | 3699 | struct hlist_head *hhd; |
59df055f | 3700 | unsigned long key; |
59df055f SR |
3701 | |
3702 | key = hash_long(ip, FTRACE_HASH_BITS); | |
3703 | ||
3704 | hhd = &ftrace_func_hash[key]; | |
3705 | ||
3706 | if (hlist_empty(hhd)) | |
3707 | return; | |
3708 | ||
3709 | /* | |
3710 | * Disable preemption for these calls to prevent a RCU grace | |
3711 | * period. This syncs the hash iteration and freeing of items | |
3712 | * on the hash. rcu_read_lock is too dangerous here. | |
3713 | */ | |
5168ae50 | 3714 | preempt_disable_notrace(); |
1bb539ca | 3715 | hlist_for_each_entry_rcu_notrace(entry, hhd, node) { |
59df055f SR |
3716 | if (entry->ip == ip) |
3717 | entry->ops->func(ip, parent_ip, &entry->data); | |
3718 | } | |
5168ae50 | 3719 | preempt_enable_notrace(); |
59df055f SR |
3720 | } |
3721 | ||
b6887d79 | 3722 | static struct ftrace_ops trace_probe_ops __read_mostly = |
59df055f | 3723 | { |
fb9fb015 | 3724 | .func = function_trace_probe_call, |
f04f24fb | 3725 | .flags = FTRACE_OPS_FL_INITIALIZED, |
33b7f99c | 3726 | INIT_OPS_HASH(trace_probe_ops) |
59df055f SR |
3727 | }; |
3728 | ||
b6887d79 | 3729 | static int ftrace_probe_registered; |
59df055f | 3730 | |
7485058e | 3731 | static void __enable_ftrace_function_probe(struct ftrace_ops_hash *old_hash) |
59df055f | 3732 | { |
b848914c | 3733 | int ret; |
59df055f SR |
3734 | int i; |
3735 | ||
19dd603e SRRH |
3736 | if (ftrace_probe_registered) { |
3737 | /* still need to update the function call sites */ | |
3738 | if (ftrace_enabled) | |
8252ecf3 SRRH |
3739 | ftrace_run_modify_code(&trace_probe_ops, FTRACE_UPDATE_CALLS, |
3740 | old_hash); | |
59df055f | 3741 | return; |
19dd603e | 3742 | } |
59df055f SR |
3743 | |
3744 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
3745 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3746 | if (hhd->first) | |
3747 | break; | |
3748 | } | |
3749 | /* Nothing registered? */ | |
3750 | if (i == FTRACE_FUNC_HASHSIZE) | |
3751 | return; | |
3752 | ||
8a56d776 | 3753 | ret = ftrace_startup(&trace_probe_ops, 0); |
b848914c | 3754 | |
b6887d79 | 3755 | ftrace_probe_registered = 1; |
59df055f SR |
3756 | } |
3757 | ||
b6887d79 | 3758 | static void __disable_ftrace_function_probe(void) |
59df055f SR |
3759 | { |
3760 | int i; | |
3761 | ||
b6887d79 | 3762 | if (!ftrace_probe_registered) |
59df055f SR |
3763 | return; |
3764 | ||
3765 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
3766 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3767 | if (hhd->first) | |
3768 | return; | |
3769 | } | |
3770 | ||
3771 | /* no more funcs left */ | |
8a56d776 | 3772 | ftrace_shutdown(&trace_probe_ops, 0); |
b848914c | 3773 | |
b6887d79 | 3774 | ftrace_probe_registered = 0; |
59df055f SR |
3775 | } |
3776 | ||
3777 | ||
7818b388 | 3778 | static void ftrace_free_entry(struct ftrace_func_probe *entry) |
59df055f | 3779 | { |
59df055f | 3780 | if (entry->ops->free) |
e67efb93 | 3781 | entry->ops->free(entry->ops, entry->ip, &entry->data); |
59df055f SR |
3782 | kfree(entry); |
3783 | } | |
3784 | ||
59df055f | 3785 | int |
b6887d79 | 3786 | register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3787 | void *data) |
3788 | { | |
7485058e | 3789 | struct ftrace_ops_hash old_hash_ops; |
b6887d79 | 3790 | struct ftrace_func_probe *entry; |
3ba00929 | 3791 | struct ftrace_glob func_g; |
33b7f99c | 3792 | struct ftrace_hash **orig_hash = &trace_probe_ops.func_hash->filter_hash; |
3296fc4e | 3793 | struct ftrace_hash *old_hash = *orig_hash; |
e1df4cb6 | 3794 | struct ftrace_hash *hash; |
59df055f SR |
3795 | struct ftrace_page *pg; |
3796 | struct dyn_ftrace *rec; | |
3ba00929 | 3797 | int not; |
6a24a244 | 3798 | unsigned long key; |
59df055f | 3799 | int count = 0; |
e1df4cb6 | 3800 | int ret; |
59df055f | 3801 | |
3ba00929 DS |
3802 | func_g.type = filter_parse_regex(glob, strlen(glob), |
3803 | &func_g.search, ¬); | |
3804 | func_g.len = strlen(func_g.search); | |
59df055f | 3805 | |
b6887d79 | 3806 | /* we do not support '!' for function probes */ |
59df055f SR |
3807 | if (WARN_ON(not)) |
3808 | return -EINVAL; | |
3809 | ||
33b7f99c | 3810 | mutex_lock(&trace_probe_ops.func_hash->regex_lock); |
59df055f | 3811 | |
7485058e SRRH |
3812 | old_hash_ops.filter_hash = old_hash; |
3813 | /* Probes only have filters */ | |
3814 | old_hash_ops.notrace_hash = NULL; | |
3815 | ||
3296fc4e | 3816 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash); |
e1df4cb6 SRRH |
3817 | if (!hash) { |
3818 | count = -ENOMEM; | |
5ae0bf59 | 3819 | goto out; |
e1df4cb6 SRRH |
3820 | } |
3821 | ||
3822 | if (unlikely(ftrace_disabled)) { | |
3823 | count = -ENODEV; | |
5ae0bf59 | 3824 | goto out; |
e1df4cb6 | 3825 | } |
59df055f | 3826 | |
5ae0bf59 SRRH |
3827 | mutex_lock(&ftrace_lock); |
3828 | ||
45a4a237 | 3829 | do_for_each_ftrace_rec(pg, rec) { |
59df055f | 3830 | |
546fece4 SRRH |
3831 | if (rec->flags & FTRACE_FL_DISABLED) |
3832 | continue; | |
3833 | ||
0b507e1e | 3834 | if (!ftrace_match_record(rec, &func_g, NULL, 0)) |
59df055f SR |
3835 | continue; |
3836 | ||
3837 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
3838 | if (!entry) { | |
b6887d79 | 3839 | /* If we did not process any, then return error */ |
59df055f SR |
3840 | if (!count) |
3841 | count = -ENOMEM; | |
3842 | goto out_unlock; | |
3843 | } | |
3844 | ||
3845 | count++; | |
3846 | ||
3847 | entry->data = data; | |
3848 | ||
3849 | /* | |
3850 | * The caller might want to do something special | |
3851 | * for each function we find. We call the callback | |
3852 | * to give the caller an opportunity to do so. | |
3853 | */ | |
e67efb93 SRRH |
3854 | if (ops->init) { |
3855 | if (ops->init(ops, rec->ip, &entry->data) < 0) { | |
59df055f SR |
3856 | /* caller does not like this func */ |
3857 | kfree(entry); | |
3858 | continue; | |
3859 | } | |
3860 | } | |
3861 | ||
e1df4cb6 SRRH |
3862 | ret = enter_record(hash, rec, 0); |
3863 | if (ret < 0) { | |
3864 | kfree(entry); | |
3865 | count = ret; | |
3866 | goto out_unlock; | |
3867 | } | |
3868 | ||
59df055f SR |
3869 | entry->ops = ops; |
3870 | entry->ip = rec->ip; | |
3871 | ||
3872 | key = hash_long(entry->ip, FTRACE_HASH_BITS); | |
3873 | hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]); | |
3874 | ||
3875 | } while_for_each_ftrace_rec(); | |
e1df4cb6 SRRH |
3876 | |
3877 | ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash); | |
8252ecf3 | 3878 | |
7485058e | 3879 | __enable_ftrace_function_probe(&old_hash_ops); |
8252ecf3 | 3880 | |
3296fc4e SRRH |
3881 | if (!ret) |
3882 | free_ftrace_hash_rcu(old_hash); | |
3883 | else | |
e1df4cb6 SRRH |
3884 | count = ret; |
3885 | ||
59df055f | 3886 | out_unlock: |
5ae0bf59 SRRH |
3887 | mutex_unlock(&ftrace_lock); |
3888 | out: | |
33b7f99c | 3889 | mutex_unlock(&trace_probe_ops.func_hash->regex_lock); |
e1df4cb6 | 3890 | free_ftrace_hash(hash); |
59df055f SR |
3891 | |
3892 | return count; | |
3893 | } | |
3894 | ||
3895 | enum { | |
b6887d79 SR |
3896 | PROBE_TEST_FUNC = 1, |
3897 | PROBE_TEST_DATA = 2 | |
59df055f SR |
3898 | }; |
3899 | ||
3900 | static void | |
b6887d79 | 3901 | __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3902 | void *data, int flags) |
3903 | { | |
e1df4cb6 | 3904 | struct ftrace_func_entry *rec_entry; |
b6887d79 | 3905 | struct ftrace_func_probe *entry; |
7818b388 | 3906 | struct ftrace_func_probe *p; |
3ba00929 | 3907 | struct ftrace_glob func_g; |
33b7f99c | 3908 | struct ftrace_hash **orig_hash = &trace_probe_ops.func_hash->filter_hash; |
3296fc4e | 3909 | struct ftrace_hash *old_hash = *orig_hash; |
7818b388 | 3910 | struct list_head free_list; |
e1df4cb6 | 3911 | struct ftrace_hash *hash; |
b67bfe0d | 3912 | struct hlist_node *tmp; |
59df055f | 3913 | char str[KSYM_SYMBOL_LEN]; |
3ba00929 | 3914 | int i, ret; |
59df055f | 3915 | |
b36461da | 3916 | if (glob && (strcmp(glob, "*") == 0 || !strlen(glob))) |
3ba00929 | 3917 | func_g.search = NULL; |
b36461da | 3918 | else if (glob) { |
59df055f SR |
3919 | int not; |
3920 | ||
3ba00929 DS |
3921 | func_g.type = filter_parse_regex(glob, strlen(glob), |
3922 | &func_g.search, ¬); | |
3923 | func_g.len = strlen(func_g.search); | |
3924 | func_g.search = glob; | |
59df055f | 3925 | |
b6887d79 | 3926 | /* we do not support '!' for function probes */ |
59df055f SR |
3927 | if (WARN_ON(not)) |
3928 | return; | |
3929 | } | |
3930 | ||
33b7f99c | 3931 | mutex_lock(&trace_probe_ops.func_hash->regex_lock); |
e1df4cb6 SRRH |
3932 | |
3933 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
3934 | if (!hash) | |
3935 | /* Hmm, should report this somehow */ | |
3936 | goto out_unlock; | |
3937 | ||
7818b388 SRRH |
3938 | INIT_LIST_HEAD(&free_list); |
3939 | ||
59df055f SR |
3940 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { |
3941 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3942 | ||
b67bfe0d | 3943 | hlist_for_each_entry_safe(entry, tmp, hhd, node) { |
59df055f SR |
3944 | |
3945 | /* break up if statements for readability */ | |
b6887d79 | 3946 | if ((flags & PROBE_TEST_FUNC) && entry->ops != ops) |
59df055f SR |
3947 | continue; |
3948 | ||
b6887d79 | 3949 | if ((flags & PROBE_TEST_DATA) && entry->data != data) |
59df055f SR |
3950 | continue; |
3951 | ||
3952 | /* do this last, since it is the most expensive */ | |
3ba00929 | 3953 | if (func_g.search) { |
59df055f SR |
3954 | kallsyms_lookup(entry->ip, NULL, NULL, |
3955 | NULL, str); | |
3ba00929 | 3956 | if (!ftrace_match(str, &func_g)) |
59df055f SR |
3957 | continue; |
3958 | } | |
3959 | ||
e1df4cb6 SRRH |
3960 | rec_entry = ftrace_lookup_ip(hash, entry->ip); |
3961 | /* It is possible more than one entry had this ip */ | |
3962 | if (rec_entry) | |
3963 | free_hash_entry(hash, rec_entry); | |
3964 | ||
740466bc | 3965 | hlist_del_rcu(&entry->node); |
7818b388 | 3966 | list_add(&entry->free_list, &free_list); |
59df055f SR |
3967 | } |
3968 | } | |
3f2367ba | 3969 | mutex_lock(&ftrace_lock); |
b6887d79 | 3970 | __disable_ftrace_function_probe(); |
e1df4cb6 SRRH |
3971 | /* |
3972 | * Remove after the disable is called. Otherwise, if the last | |
3973 | * probe is removed, a null hash means *all enabled*. | |
3974 | */ | |
3296fc4e | 3975 | ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash); |
7818b388 | 3976 | synchronize_sched(); |
3296fc4e SRRH |
3977 | if (!ret) |
3978 | free_ftrace_hash_rcu(old_hash); | |
3979 | ||
7818b388 SRRH |
3980 | list_for_each_entry_safe(entry, p, &free_list, free_list) { |
3981 | list_del(&entry->free_list); | |
3982 | ftrace_free_entry(entry); | |
3983 | } | |
3f2367ba | 3984 | mutex_unlock(&ftrace_lock); |
3ba00929 | 3985 | |
e1df4cb6 | 3986 | out_unlock: |
33b7f99c | 3987 | mutex_unlock(&trace_probe_ops.func_hash->regex_lock); |
e1df4cb6 | 3988 | free_ftrace_hash(hash); |
59df055f SR |
3989 | } |
3990 | ||
3991 | void | |
b6887d79 | 3992 | unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3993 | void *data) |
3994 | { | |
b6887d79 SR |
3995 | __unregister_ftrace_function_probe(glob, ops, data, |
3996 | PROBE_TEST_FUNC | PROBE_TEST_DATA); | |
59df055f SR |
3997 | } |
3998 | ||
3999 | void | |
b6887d79 | 4000 | unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops) |
59df055f | 4001 | { |
b6887d79 | 4002 | __unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC); |
59df055f SR |
4003 | } |
4004 | ||
b6887d79 | 4005 | void unregister_ftrace_function_probe_all(char *glob) |
59df055f | 4006 | { |
b6887d79 | 4007 | __unregister_ftrace_function_probe(glob, NULL, NULL, 0); |
59df055f SR |
4008 | } |
4009 | ||
f6180773 SR |
4010 | static LIST_HEAD(ftrace_commands); |
4011 | static DEFINE_MUTEX(ftrace_cmd_mutex); | |
4012 | ||
38de93ab TZ |
4013 | /* |
4014 | * Currently we only register ftrace commands from __init, so mark this | |
4015 | * __init too. | |
4016 | */ | |
4017 | __init int register_ftrace_command(struct ftrace_func_command *cmd) | |
f6180773 SR |
4018 | { |
4019 | struct ftrace_func_command *p; | |
4020 | int ret = 0; | |
4021 | ||
4022 | mutex_lock(&ftrace_cmd_mutex); | |
4023 | list_for_each_entry(p, &ftrace_commands, list) { | |
4024 | if (strcmp(cmd->name, p->name) == 0) { | |
4025 | ret = -EBUSY; | |
4026 | goto out_unlock; | |
4027 | } | |
4028 | } | |
4029 | list_add(&cmd->list, &ftrace_commands); | |
4030 | out_unlock: | |
4031 | mutex_unlock(&ftrace_cmd_mutex); | |
4032 | ||
4033 | return ret; | |
4034 | } | |
4035 | ||
38de93ab TZ |
4036 | /* |
4037 | * Currently we only unregister ftrace commands from __init, so mark | |
4038 | * this __init too. | |
4039 | */ | |
4040 | __init int unregister_ftrace_command(struct ftrace_func_command *cmd) | |
f6180773 SR |
4041 | { |
4042 | struct ftrace_func_command *p, *n; | |
4043 | int ret = -ENODEV; | |
4044 | ||
4045 | mutex_lock(&ftrace_cmd_mutex); | |
4046 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { | |
4047 | if (strcmp(cmd->name, p->name) == 0) { | |
4048 | ret = 0; | |
4049 | list_del_init(&p->list); | |
4050 | goto out_unlock; | |
4051 | } | |
4052 | } | |
4053 | out_unlock: | |
4054 | mutex_unlock(&ftrace_cmd_mutex); | |
4055 | ||
4056 | return ret; | |
4057 | } | |
4058 | ||
33dc9b12 SR |
4059 | static int ftrace_process_regex(struct ftrace_hash *hash, |
4060 | char *buff, int len, int enable) | |
64e7c440 | 4061 | { |
f6180773 | 4062 | char *func, *command, *next = buff; |
6a24a244 | 4063 | struct ftrace_func_command *p; |
0aff1c0c | 4064 | int ret = -EINVAL; |
64e7c440 SR |
4065 | |
4066 | func = strsep(&next, ":"); | |
4067 | ||
4068 | if (!next) { | |
1cf41dd7 | 4069 | ret = ftrace_match_records(hash, func, len); |
b448c4e3 SR |
4070 | if (!ret) |
4071 | ret = -EINVAL; | |
4072 | if (ret < 0) | |
4073 | return ret; | |
4074 | return 0; | |
64e7c440 SR |
4075 | } |
4076 | ||
f6180773 | 4077 | /* command found */ |
64e7c440 SR |
4078 | |
4079 | command = strsep(&next, ":"); | |
4080 | ||
f6180773 SR |
4081 | mutex_lock(&ftrace_cmd_mutex); |
4082 | list_for_each_entry(p, &ftrace_commands, list) { | |
4083 | if (strcmp(p->name, command) == 0) { | |
43dd61c9 | 4084 | ret = p->func(hash, func, command, next, enable); |
f6180773 SR |
4085 | goto out_unlock; |
4086 | } | |
64e7c440 | 4087 | } |
f6180773 SR |
4088 | out_unlock: |
4089 | mutex_unlock(&ftrace_cmd_mutex); | |
64e7c440 | 4090 | |
f6180773 | 4091 | return ret; |
64e7c440 SR |
4092 | } |
4093 | ||
e309b41d | 4094 | static ssize_t |
41c52c0d SR |
4095 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
4096 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
4097 | { |
4098 | struct ftrace_iterator *iter; | |
689fd8b6 | 4099 | struct trace_parser *parser; |
4100 | ssize_t ret, read; | |
5072c59f | 4101 | |
4ba7978e | 4102 | if (!cnt) |
5072c59f SR |
4103 | return 0; |
4104 | ||
5072c59f SR |
4105 | if (file->f_mode & FMODE_READ) { |
4106 | struct seq_file *m = file->private_data; | |
4107 | iter = m->private; | |
4108 | } else | |
4109 | iter = file->private_data; | |
4110 | ||
f04f24fb | 4111 | if (unlikely(ftrace_disabled)) |
3f2367ba MH |
4112 | return -ENODEV; |
4113 | ||
4114 | /* iter->hash is a local copy, so we don't need regex_lock */ | |
f04f24fb | 4115 | |
689fd8b6 | 4116 | parser = &iter->parser; |
4117 | read = trace_get_user(parser, ubuf, cnt, ppos); | |
5072c59f | 4118 | |
4ba7978e | 4119 | if (read >= 0 && trace_parser_loaded(parser) && |
689fd8b6 | 4120 | !trace_parser_cont(parser)) { |
33dc9b12 | 4121 | ret = ftrace_process_regex(iter->hash, parser->buffer, |
689fd8b6 | 4122 | parser->idx, enable); |
313254a9 | 4123 | trace_parser_clear(parser); |
7c088b51 | 4124 | if (ret < 0) |
3f2367ba | 4125 | goto out; |
eda1e328 | 4126 | } |
5072c59f | 4127 | |
5072c59f | 4128 | ret = read; |
3f2367ba | 4129 | out: |
5072c59f SR |
4130 | return ret; |
4131 | } | |
4132 | ||
fc13cb0c | 4133 | ssize_t |
41c52c0d SR |
4134 | ftrace_filter_write(struct file *file, const char __user *ubuf, |
4135 | size_t cnt, loff_t *ppos) | |
4136 | { | |
4137 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
4138 | } | |
4139 | ||
fc13cb0c | 4140 | ssize_t |
41c52c0d SR |
4141 | ftrace_notrace_write(struct file *file, const char __user *ubuf, |
4142 | size_t cnt, loff_t *ppos) | |
4143 | { | |
4144 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
4145 | } | |
4146 | ||
33dc9b12 | 4147 | static int |
647664ea MH |
4148 | ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) |
4149 | { | |
4150 | struct ftrace_func_entry *entry; | |
4151 | ||
4152 | if (!ftrace_location(ip)) | |
4153 | return -EINVAL; | |
4154 | ||
4155 | if (remove) { | |
4156 | entry = ftrace_lookup_ip(hash, ip); | |
4157 | if (!entry) | |
4158 | return -ENOENT; | |
4159 | free_hash_entry(hash, entry); | |
4160 | return 0; | |
4161 | } | |
4162 | ||
4163 | return add_hash_entry(hash, ip); | |
4164 | } | |
4165 | ||
8252ecf3 | 4166 | static void ftrace_ops_update_code(struct ftrace_ops *ops, |
7485058e | 4167 | struct ftrace_ops_hash *old_hash) |
1c80c432 | 4168 | { |
8f86f837 SRRH |
4169 | struct ftrace_ops *op; |
4170 | ||
4171 | if (!ftrace_enabled) | |
4172 | return; | |
4173 | ||
4174 | if (ops->flags & FTRACE_OPS_FL_ENABLED) { | |
8252ecf3 | 4175 | ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS, old_hash); |
8f86f837 SRRH |
4176 | return; |
4177 | } | |
4178 | ||
4179 | /* | |
4180 | * If this is the shared global_ops filter, then we need to | |
4181 | * check if there is another ops that shares it, is enabled. | |
4182 | * If so, we still need to run the modify code. | |
4183 | */ | |
4184 | if (ops->func_hash != &global_ops.local_hash) | |
4185 | return; | |
4186 | ||
4187 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
4188 | if (op->func_hash == &global_ops.local_hash && | |
4189 | op->flags & FTRACE_OPS_FL_ENABLED) { | |
4190 | ftrace_run_modify_code(op, FTRACE_UPDATE_CALLS, old_hash); | |
4191 | /* Only need to do this once */ | |
4192 | return; | |
4193 | } | |
4194 | } while_for_each_ftrace_op(op); | |
1c80c432 SRRH |
4195 | } |
4196 | ||
647664ea MH |
4197 | static int |
4198 | ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, | |
4199 | unsigned long ip, int remove, int reset, int enable) | |
41c52c0d | 4200 | { |
33dc9b12 | 4201 | struct ftrace_hash **orig_hash; |
7485058e | 4202 | struct ftrace_ops_hash old_hash_ops; |
3296fc4e | 4203 | struct ftrace_hash *old_hash; |
f45948e8 | 4204 | struct ftrace_hash *hash; |
33dc9b12 | 4205 | int ret; |
f45948e8 | 4206 | |
41c52c0d | 4207 | if (unlikely(ftrace_disabled)) |
33dc9b12 | 4208 | return -ENODEV; |
41c52c0d | 4209 | |
33b7f99c | 4210 | mutex_lock(&ops->func_hash->regex_lock); |
3f2367ba | 4211 | |
f45948e8 | 4212 | if (enable) |
33b7f99c | 4213 | orig_hash = &ops->func_hash->filter_hash; |
f45948e8 | 4214 | else |
33b7f99c | 4215 | orig_hash = &ops->func_hash->notrace_hash; |
33dc9b12 | 4216 | |
b972cc58 WN |
4217 | if (reset) |
4218 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); | |
4219 | else | |
4220 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
4221 | ||
3f2367ba MH |
4222 | if (!hash) { |
4223 | ret = -ENOMEM; | |
4224 | goto out_regex_unlock; | |
4225 | } | |
f45948e8 | 4226 | |
ac483c44 JO |
4227 | if (buf && !ftrace_match_records(hash, buf, len)) { |
4228 | ret = -EINVAL; | |
4229 | goto out_regex_unlock; | |
4230 | } | |
647664ea MH |
4231 | if (ip) { |
4232 | ret = ftrace_match_addr(hash, ip, remove); | |
4233 | if (ret < 0) | |
4234 | goto out_regex_unlock; | |
4235 | } | |
33dc9b12 SR |
4236 | |
4237 | mutex_lock(&ftrace_lock); | |
3296fc4e | 4238 | old_hash = *orig_hash; |
7485058e SRRH |
4239 | old_hash_ops.filter_hash = ops->func_hash->filter_hash; |
4240 | old_hash_ops.notrace_hash = ops->func_hash->notrace_hash; | |
41fb61c2 | 4241 | ret = ftrace_hash_move(ops, enable, orig_hash, hash); |
3296fc4e | 4242 | if (!ret) { |
7485058e | 4243 | ftrace_ops_update_code(ops, &old_hash_ops); |
3296fc4e SRRH |
4244 | free_ftrace_hash_rcu(old_hash); |
4245 | } | |
33dc9b12 SR |
4246 | mutex_unlock(&ftrace_lock); |
4247 | ||
ac483c44 | 4248 | out_regex_unlock: |
33b7f99c | 4249 | mutex_unlock(&ops->func_hash->regex_lock); |
33dc9b12 SR |
4250 | |
4251 | free_ftrace_hash(hash); | |
4252 | return ret; | |
41c52c0d SR |
4253 | } |
4254 | ||
647664ea MH |
4255 | static int |
4256 | ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove, | |
4257 | int reset, int enable) | |
4258 | { | |
4259 | return ftrace_set_hash(ops, 0, 0, ip, remove, reset, enable); | |
4260 | } | |
4261 | ||
4262 | /** | |
4263 | * ftrace_set_filter_ip - set a function to filter on in ftrace by address | |
4264 | * @ops - the ops to set the filter with | |
4265 | * @ip - the address to add to or remove from the filter. | |
4266 | * @remove - non zero to remove the ip from the filter | |
4267 | * @reset - non zero to reset all filters before applying this filter. | |
4268 | * | |
4269 | * Filters denote which functions should be enabled when tracing is enabled | |
4270 | * If @ip is NULL, it failes to update filter. | |
4271 | */ | |
4272 | int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, | |
4273 | int remove, int reset) | |
4274 | { | |
f04f24fb | 4275 | ftrace_ops_init(ops); |
647664ea MH |
4276 | return ftrace_set_addr(ops, ip, remove, reset, 1); |
4277 | } | |
4278 | EXPORT_SYMBOL_GPL(ftrace_set_filter_ip); | |
4279 | ||
d032ae89 JF |
4280 | /** |
4281 | * ftrace_ops_set_global_filter - setup ops to use global filters | |
4282 | * @ops - the ops which will use the global filters | |
4283 | * | |
4284 | * ftrace users who need global function trace filtering should call this. | |
4285 | * It can set the global filter only if ops were not initialized before. | |
4286 | */ | |
4287 | void ftrace_ops_set_global_filter(struct ftrace_ops *ops) | |
4288 | { | |
4289 | if (ops->flags & FTRACE_OPS_FL_INITIALIZED) | |
4290 | return; | |
4291 | ||
4292 | ftrace_ops_init(ops); | |
4293 | ops->func_hash = &global_ops.local_hash; | |
4294 | } | |
4295 | EXPORT_SYMBOL_GPL(ftrace_ops_set_global_filter); | |
4296 | ||
647664ea MH |
4297 | static int |
4298 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, | |
4299 | int reset, int enable) | |
4300 | { | |
4301 | return ftrace_set_hash(ops, buf, len, 0, 0, reset, enable); | |
4302 | } | |
4303 | ||
77a2b37d SR |
4304 | /** |
4305 | * ftrace_set_filter - set a function to filter on in ftrace | |
936e074b SR |
4306 | * @ops - the ops to set the filter with |
4307 | * @buf - the string that holds the function filter text. | |
4308 | * @len - the length of the string. | |
4309 | * @reset - non zero to reset all filters before applying this filter. | |
4310 | * | |
4311 | * Filters denote which functions should be enabled when tracing is enabled. | |
4312 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
4313 | */ | |
ac483c44 | 4314 | int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
4315 | int len, int reset) |
4316 | { | |
f04f24fb | 4317 | ftrace_ops_init(ops); |
ac483c44 | 4318 | return ftrace_set_regex(ops, buf, len, reset, 1); |
936e074b SR |
4319 | } |
4320 | EXPORT_SYMBOL_GPL(ftrace_set_filter); | |
4321 | ||
4322 | /** | |
4323 | * ftrace_set_notrace - set a function to not trace in ftrace | |
4324 | * @ops - the ops to set the notrace filter with | |
4325 | * @buf - the string that holds the function notrace text. | |
4326 | * @len - the length of the string. | |
4327 | * @reset - non zero to reset all filters before applying this filter. | |
4328 | * | |
4329 | * Notrace Filters denote which functions should not be enabled when tracing | |
4330 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
4331 | * for tracing. | |
4332 | */ | |
ac483c44 | 4333 | int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
4334 | int len, int reset) |
4335 | { | |
f04f24fb | 4336 | ftrace_ops_init(ops); |
ac483c44 | 4337 | return ftrace_set_regex(ops, buf, len, reset, 0); |
936e074b SR |
4338 | } |
4339 | EXPORT_SYMBOL_GPL(ftrace_set_notrace); | |
4340 | /** | |
8d1b065d | 4341 | * ftrace_set_global_filter - set a function to filter on with global tracers |
77a2b37d SR |
4342 | * @buf - the string that holds the function filter text. |
4343 | * @len - the length of the string. | |
4344 | * @reset - non zero to reset all filters before applying this filter. | |
4345 | * | |
4346 | * Filters denote which functions should be enabled when tracing is enabled. | |
4347 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
4348 | */ | |
936e074b | 4349 | void ftrace_set_global_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 4350 | { |
f45948e8 | 4351 | ftrace_set_regex(&global_ops, buf, len, reset, 1); |
41c52c0d | 4352 | } |
936e074b | 4353 | EXPORT_SYMBOL_GPL(ftrace_set_global_filter); |
4eebcc81 | 4354 | |
41c52c0d | 4355 | /** |
8d1b065d | 4356 | * ftrace_set_global_notrace - set a function to not trace with global tracers |
41c52c0d SR |
4357 | * @buf - the string that holds the function notrace text. |
4358 | * @len - the length of the string. | |
4359 | * @reset - non zero to reset all filters before applying this filter. | |
4360 | * | |
4361 | * Notrace Filters denote which functions should not be enabled when tracing | |
4362 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
4363 | * for tracing. | |
4364 | */ | |
936e074b | 4365 | void ftrace_set_global_notrace(unsigned char *buf, int len, int reset) |
41c52c0d | 4366 | { |
f45948e8 | 4367 | ftrace_set_regex(&global_ops, buf, len, reset, 0); |
77a2b37d | 4368 | } |
936e074b | 4369 | EXPORT_SYMBOL_GPL(ftrace_set_global_notrace); |
77a2b37d | 4370 | |
2af15d6a SR |
4371 | /* |
4372 | * command line interface to allow users to set filters on boot up. | |
4373 | */ | |
4374 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE | |
4375 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; | |
4376 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; | |
4377 | ||
f1ed7c74 SRRH |
4378 | /* Used by function selftest to not test if filter is set */ |
4379 | bool ftrace_filter_param __initdata; | |
4380 | ||
2af15d6a SR |
4381 | static int __init set_ftrace_notrace(char *str) |
4382 | { | |
f1ed7c74 | 4383 | ftrace_filter_param = true; |
75761cc1 | 4384 | strlcpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
4385 | return 1; |
4386 | } | |
4387 | __setup("ftrace_notrace=", set_ftrace_notrace); | |
4388 | ||
4389 | static int __init set_ftrace_filter(char *str) | |
4390 | { | |
f1ed7c74 | 4391 | ftrace_filter_param = true; |
75761cc1 | 4392 | strlcpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
4393 | return 1; |
4394 | } | |
4395 | __setup("ftrace_filter=", set_ftrace_filter); | |
4396 | ||
369bc18f | 4397 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
f6060f46 | 4398 | static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; |
0d7d9a16 | 4399 | static char ftrace_graph_notrace_buf[FTRACE_FILTER_SIZE] __initdata; |
b9b0c831 | 4400 | static int ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer); |
801c29fd | 4401 | |
f3bea491 SRRH |
4402 | static unsigned long save_global_trampoline; |
4403 | static unsigned long save_global_flags; | |
4404 | ||
369bc18f SA |
4405 | static int __init set_graph_function(char *str) |
4406 | { | |
06f43d66 | 4407 | strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); |
369bc18f SA |
4408 | return 1; |
4409 | } | |
4410 | __setup("ftrace_graph_filter=", set_graph_function); | |
4411 | ||
0d7d9a16 NK |
4412 | static int __init set_graph_notrace_function(char *str) |
4413 | { | |
4414 | strlcpy(ftrace_graph_notrace_buf, str, FTRACE_FILTER_SIZE); | |
4415 | return 1; | |
4416 | } | |
4417 | __setup("ftrace_graph_notrace=", set_graph_notrace_function); | |
4418 | ||
65a50c65 TB |
4419 | static int __init set_graph_max_depth_function(char *str) |
4420 | { | |
4421 | if (!str) | |
4422 | return 0; | |
4423 | fgraph_max_depth = simple_strtoul(str, NULL, 0); | |
4424 | return 1; | |
4425 | } | |
4426 | __setup("ftrace_graph_max_depth=", set_graph_max_depth_function); | |
0d7d9a16 NK |
4427 | |
4428 | static void __init set_ftrace_early_graph(char *buf, int enable) | |
369bc18f SA |
4429 | { |
4430 | int ret; | |
4431 | char *func; | |
b9b0c831 | 4432 | struct ftrace_hash *hash; |
0d7d9a16 | 4433 | |
92ad18ec SRV |
4434 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); |
4435 | if (WARN_ON(!hash)) | |
4436 | return; | |
369bc18f SA |
4437 | |
4438 | while (buf) { | |
4439 | func = strsep(&buf, ","); | |
4440 | /* we allow only one expression at a time */ | |
b9b0c831 | 4441 | ret = ftrace_graph_set_hash(hash, func); |
369bc18f SA |
4442 | if (ret) |
4443 | printk(KERN_DEBUG "ftrace: function %s not " | |
4444 | "traceable\n", func); | |
4445 | } | |
92ad18ec SRV |
4446 | |
4447 | if (enable) | |
4448 | ftrace_graph_hash = hash; | |
4449 | else | |
4450 | ftrace_graph_notrace_hash = hash; | |
369bc18f SA |
4451 | } |
4452 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
4453 | ||
2a85a37f SR |
4454 | void __init |
4455 | ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable) | |
2af15d6a SR |
4456 | { |
4457 | char *func; | |
4458 | ||
f04f24fb MH |
4459 | ftrace_ops_init(ops); |
4460 | ||
2af15d6a SR |
4461 | while (buf) { |
4462 | func = strsep(&buf, ","); | |
f45948e8 | 4463 | ftrace_set_regex(ops, func, strlen(func), 0, enable); |
2af15d6a SR |
4464 | } |
4465 | } | |
4466 | ||
4467 | static void __init set_ftrace_early_filters(void) | |
4468 | { | |
4469 | if (ftrace_filter_buf[0]) | |
2a85a37f | 4470 | ftrace_set_early_filter(&global_ops, ftrace_filter_buf, 1); |
2af15d6a | 4471 | if (ftrace_notrace_buf[0]) |
2a85a37f | 4472 | ftrace_set_early_filter(&global_ops, ftrace_notrace_buf, 0); |
369bc18f SA |
4473 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
4474 | if (ftrace_graph_buf[0]) | |
0d7d9a16 NK |
4475 | set_ftrace_early_graph(ftrace_graph_buf, 1); |
4476 | if (ftrace_graph_notrace_buf[0]) | |
4477 | set_ftrace_early_graph(ftrace_graph_notrace_buf, 0); | |
369bc18f | 4478 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
2af15d6a SR |
4479 | } |
4480 | ||
fc13cb0c | 4481 | int ftrace_regex_release(struct inode *inode, struct file *file) |
5072c59f SR |
4482 | { |
4483 | struct seq_file *m = (struct seq_file *)file->private_data; | |
7485058e | 4484 | struct ftrace_ops_hash old_hash_ops; |
5072c59f | 4485 | struct ftrace_iterator *iter; |
33dc9b12 | 4486 | struct ftrace_hash **orig_hash; |
3296fc4e | 4487 | struct ftrace_hash *old_hash; |
689fd8b6 | 4488 | struct trace_parser *parser; |
ed926f9b | 4489 | int filter_hash; |
33dc9b12 | 4490 | int ret; |
5072c59f | 4491 | |
5072c59f SR |
4492 | if (file->f_mode & FMODE_READ) { |
4493 | iter = m->private; | |
5072c59f SR |
4494 | seq_release(inode, file); |
4495 | } else | |
4496 | iter = file->private_data; | |
4497 | ||
689fd8b6 | 4498 | parser = &iter->parser; |
4499 | if (trace_parser_loaded(parser)) { | |
4500 | parser->buffer[parser->idx] = 0; | |
1cf41dd7 | 4501 | ftrace_match_records(iter->hash, parser->buffer, parser->idx); |
5072c59f SR |
4502 | } |
4503 | ||
689fd8b6 | 4504 | trace_parser_put(parser); |
689fd8b6 | 4505 | |
33b7f99c | 4506 | mutex_lock(&iter->ops->func_hash->regex_lock); |
3f2367ba | 4507 | |
058e297d | 4508 | if (file->f_mode & FMODE_WRITE) { |
ed926f9b SR |
4509 | filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); |
4510 | ||
4511 | if (filter_hash) | |
33b7f99c | 4512 | orig_hash = &iter->ops->func_hash->filter_hash; |
ed926f9b | 4513 | else |
33b7f99c | 4514 | orig_hash = &iter->ops->func_hash->notrace_hash; |
33dc9b12 | 4515 | |
058e297d | 4516 | mutex_lock(&ftrace_lock); |
3296fc4e | 4517 | old_hash = *orig_hash; |
7485058e SRRH |
4518 | old_hash_ops.filter_hash = iter->ops->func_hash->filter_hash; |
4519 | old_hash_ops.notrace_hash = iter->ops->func_hash->notrace_hash; | |
41fb61c2 SR |
4520 | ret = ftrace_hash_move(iter->ops, filter_hash, |
4521 | orig_hash, iter->hash); | |
3296fc4e | 4522 | if (!ret) { |
7485058e | 4523 | ftrace_ops_update_code(iter->ops, &old_hash_ops); |
3296fc4e SRRH |
4524 | free_ftrace_hash_rcu(old_hash); |
4525 | } | |
058e297d SR |
4526 | mutex_unlock(&ftrace_lock); |
4527 | } | |
3f2367ba | 4528 | |
33b7f99c | 4529 | mutex_unlock(&iter->ops->func_hash->regex_lock); |
33dc9b12 SR |
4530 | free_ftrace_hash(iter->hash); |
4531 | kfree(iter); | |
058e297d | 4532 | |
5072c59f SR |
4533 | return 0; |
4534 | } | |
4535 | ||
5e2336a0 | 4536 | static const struct file_operations ftrace_avail_fops = { |
5072c59f SR |
4537 | .open = ftrace_avail_open, |
4538 | .read = seq_read, | |
4539 | .llseek = seq_lseek, | |
3be04b47 | 4540 | .release = seq_release_private, |
5072c59f SR |
4541 | }; |
4542 | ||
647bcd03 SR |
4543 | static const struct file_operations ftrace_enabled_fops = { |
4544 | .open = ftrace_enabled_open, | |
4545 | .read = seq_read, | |
4546 | .llseek = seq_lseek, | |
4547 | .release = seq_release_private, | |
4548 | }; | |
4549 | ||
5e2336a0 | 4550 | static const struct file_operations ftrace_filter_fops = { |
5072c59f | 4551 | .open = ftrace_filter_open, |
850a80cf | 4552 | .read = seq_read, |
5072c59f | 4553 | .write = ftrace_filter_write, |
098c879e | 4554 | .llseek = tracing_lseek, |
1cf41dd7 | 4555 | .release = ftrace_regex_release, |
5072c59f SR |
4556 | }; |
4557 | ||
5e2336a0 | 4558 | static const struct file_operations ftrace_notrace_fops = { |
41c52c0d | 4559 | .open = ftrace_notrace_open, |
850a80cf | 4560 | .read = seq_read, |
41c52c0d | 4561 | .write = ftrace_notrace_write, |
098c879e | 4562 | .llseek = tracing_lseek, |
1cf41dd7 | 4563 | .release = ftrace_regex_release, |
41c52c0d SR |
4564 | }; |
4565 | ||
ea4e2bc4 SR |
4566 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
4567 | ||
4568 | static DEFINE_MUTEX(graph_lock); | |
4569 | ||
b9b0c831 NK |
4570 | struct ftrace_hash *ftrace_graph_hash = EMPTY_HASH; |
4571 | struct ftrace_hash *ftrace_graph_notrace_hash = EMPTY_HASH; | |
4572 | ||
4573 | enum graph_filter_type { | |
4574 | GRAPH_FILTER_NOTRACE = 0, | |
4575 | GRAPH_FILTER_FUNCTION, | |
4576 | }; | |
ea4e2bc4 | 4577 | |
555fc781 SRV |
4578 | #define FTRACE_GRAPH_EMPTY ((void *)1) |
4579 | ||
faf982a6 | 4580 | struct ftrace_graph_data { |
e704eff3 SRV |
4581 | struct ftrace_hash *hash; |
4582 | struct ftrace_func_entry *entry; | |
4583 | int idx; /* for hash table iteration */ | |
4584 | enum graph_filter_type type; | |
4585 | struct ftrace_hash *new_hash; | |
4586 | const struct seq_operations *seq_ops; | |
4587 | struct trace_parser parser; | |
faf982a6 NK |
4588 | }; |
4589 | ||
ea4e2bc4 | 4590 | static void * |
85951842 | 4591 | __g_next(struct seq_file *m, loff_t *pos) |
ea4e2bc4 | 4592 | { |
faf982a6 | 4593 | struct ftrace_graph_data *fgd = m->private; |
b9b0c831 NK |
4594 | struct ftrace_func_entry *entry = fgd->entry; |
4595 | struct hlist_head *head; | |
4596 | int i, idx = fgd->idx; | |
faf982a6 | 4597 | |
b9b0c831 | 4598 | if (*pos >= fgd->hash->count) |
ea4e2bc4 | 4599 | return NULL; |
b9b0c831 NK |
4600 | |
4601 | if (entry) { | |
4602 | hlist_for_each_entry_continue(entry, hlist) { | |
4603 | fgd->entry = entry; | |
4604 | return entry; | |
4605 | } | |
4606 | ||
4607 | idx++; | |
4608 | } | |
4609 | ||
4610 | for (i = idx; i < 1 << fgd->hash->size_bits; i++) { | |
4611 | head = &fgd->hash->buckets[i]; | |
4612 | hlist_for_each_entry(entry, head, hlist) { | |
4613 | fgd->entry = entry; | |
4614 | fgd->idx = i; | |
4615 | return entry; | |
4616 | } | |
4617 | } | |
4618 | return NULL; | |
85951842 | 4619 | } |
ea4e2bc4 | 4620 | |
85951842 LZ |
4621 | static void * |
4622 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
4623 | { | |
4624 | (*pos)++; | |
4625 | return __g_next(m, pos); | |
ea4e2bc4 SR |
4626 | } |
4627 | ||
4628 | static void *g_start(struct seq_file *m, loff_t *pos) | |
4629 | { | |
faf982a6 NK |
4630 | struct ftrace_graph_data *fgd = m->private; |
4631 | ||
ea4e2bc4 SR |
4632 | mutex_lock(&graph_lock); |
4633 | ||
649b988b SRV |
4634 | if (fgd->type == GRAPH_FILTER_FUNCTION) |
4635 | fgd->hash = rcu_dereference_protected(ftrace_graph_hash, | |
4636 | lockdep_is_held(&graph_lock)); | |
4637 | else | |
4638 | fgd->hash = rcu_dereference_protected(ftrace_graph_notrace_hash, | |
4639 | lockdep_is_held(&graph_lock)); | |
4640 | ||
f9349a8f | 4641 | /* Nothing, tell g_show to print all functions are enabled */ |
b9b0c831 | 4642 | if (ftrace_hash_empty(fgd->hash) && !*pos) |
555fc781 | 4643 | return FTRACE_GRAPH_EMPTY; |
f9349a8f | 4644 | |
b9b0c831 NK |
4645 | fgd->idx = 0; |
4646 | fgd->entry = NULL; | |
85951842 | 4647 | return __g_next(m, pos); |
ea4e2bc4 SR |
4648 | } |
4649 | ||
4650 | static void g_stop(struct seq_file *m, void *p) | |
4651 | { | |
4652 | mutex_unlock(&graph_lock); | |
4653 | } | |
4654 | ||
4655 | static int g_show(struct seq_file *m, void *v) | |
4656 | { | |
b9b0c831 | 4657 | struct ftrace_func_entry *entry = v; |
ea4e2bc4 | 4658 | |
b9b0c831 | 4659 | if (!entry) |
ea4e2bc4 SR |
4660 | return 0; |
4661 | ||
555fc781 | 4662 | if (entry == FTRACE_GRAPH_EMPTY) { |
280d1429 NK |
4663 | struct ftrace_graph_data *fgd = m->private; |
4664 | ||
b9b0c831 | 4665 | if (fgd->type == GRAPH_FILTER_FUNCTION) |
fa6f0cc7 | 4666 | seq_puts(m, "#### all functions enabled ####\n"); |
280d1429 | 4667 | else |
fa6f0cc7 | 4668 | seq_puts(m, "#### no functions disabled ####\n"); |
f9349a8f FW |
4669 | return 0; |
4670 | } | |
4671 | ||
b9b0c831 | 4672 | seq_printf(m, "%ps\n", (void *)entry->ip); |
ea4e2bc4 SR |
4673 | |
4674 | return 0; | |
4675 | } | |
4676 | ||
88e9d34c | 4677 | static const struct seq_operations ftrace_graph_seq_ops = { |
ea4e2bc4 SR |
4678 | .start = g_start, |
4679 | .next = g_next, | |
4680 | .stop = g_stop, | |
4681 | .show = g_show, | |
4682 | }; | |
4683 | ||
4684 | static int | |
faf982a6 NK |
4685 | __ftrace_graph_open(struct inode *inode, struct file *file, |
4686 | struct ftrace_graph_data *fgd) | |
ea4e2bc4 SR |
4687 | { |
4688 | int ret = 0; | |
b9b0c831 | 4689 | struct ftrace_hash *new_hash = NULL; |
ea4e2bc4 | 4690 | |
b9b0c831 NK |
4691 | if (file->f_mode & FMODE_WRITE) { |
4692 | const int size_bits = FTRACE_HASH_DEFAULT_BITS; | |
4693 | ||
e704eff3 SRV |
4694 | if (trace_parser_get_init(&fgd->parser, FTRACE_BUFF_MAX)) |
4695 | return -ENOMEM; | |
4696 | ||
b9b0c831 NK |
4697 | if (file->f_flags & O_TRUNC) |
4698 | new_hash = alloc_ftrace_hash(size_bits); | |
4699 | else | |
4700 | new_hash = alloc_and_copy_ftrace_hash(size_bits, | |
4701 | fgd->hash); | |
4702 | if (!new_hash) { | |
4703 | ret = -ENOMEM; | |
4704 | goto out; | |
4705 | } | |
ea4e2bc4 SR |
4706 | } |
4707 | ||
faf982a6 | 4708 | if (file->f_mode & FMODE_READ) { |
b9b0c831 | 4709 | ret = seq_open(file, &ftrace_graph_seq_ops); |
faf982a6 NK |
4710 | if (!ret) { |
4711 | struct seq_file *m = file->private_data; | |
4712 | m->private = fgd; | |
b9b0c831 NK |
4713 | } else { |
4714 | /* Failed */ | |
4715 | free_ftrace_hash(new_hash); | |
4716 | new_hash = NULL; | |
faf982a6 NK |
4717 | } |
4718 | } else | |
4719 | file->private_data = fgd; | |
ea4e2bc4 | 4720 | |
b9b0c831 | 4721 | out: |
e704eff3 SRV |
4722 | if (ret < 0 && file->f_mode & FMODE_WRITE) |
4723 | trace_parser_put(&fgd->parser); | |
4724 | ||
b9b0c831 | 4725 | fgd->new_hash = new_hash; |
649b988b SRV |
4726 | |
4727 | /* | |
4728 | * All uses of fgd->hash must be taken with the graph_lock | |
4729 | * held. The graph_lock is going to be released, so force | |
4730 | * fgd->hash to be reinitialized when it is taken again. | |
4731 | */ | |
4732 | fgd->hash = NULL; | |
4733 | ||
ea4e2bc4 SR |
4734 | return ret; |
4735 | } | |
4736 | ||
faf982a6 NK |
4737 | static int |
4738 | ftrace_graph_open(struct inode *inode, struct file *file) | |
4739 | { | |
4740 | struct ftrace_graph_data *fgd; | |
b9b0c831 | 4741 | int ret; |
faf982a6 NK |
4742 | |
4743 | if (unlikely(ftrace_disabled)) | |
4744 | return -ENODEV; | |
4745 | ||
4746 | fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); | |
4747 | if (fgd == NULL) | |
4748 | return -ENOMEM; | |
4749 | ||
b9b0c831 NK |
4750 | mutex_lock(&graph_lock); |
4751 | ||
649b988b SRV |
4752 | fgd->hash = rcu_dereference_protected(ftrace_graph_hash, |
4753 | lockdep_is_held(&graph_lock)); | |
b9b0c831 | 4754 | fgd->type = GRAPH_FILTER_FUNCTION; |
faf982a6 NK |
4755 | fgd->seq_ops = &ftrace_graph_seq_ops; |
4756 | ||
b9b0c831 NK |
4757 | ret = __ftrace_graph_open(inode, file, fgd); |
4758 | if (ret < 0) | |
4759 | kfree(fgd); | |
4760 | ||
4761 | mutex_unlock(&graph_lock); | |
4762 | return ret; | |
faf982a6 NK |
4763 | } |
4764 | ||
29ad23b0 NK |
4765 | static int |
4766 | ftrace_graph_notrace_open(struct inode *inode, struct file *file) | |
4767 | { | |
4768 | struct ftrace_graph_data *fgd; | |
b9b0c831 | 4769 | int ret; |
29ad23b0 NK |
4770 | |
4771 | if (unlikely(ftrace_disabled)) | |
4772 | return -ENODEV; | |
4773 | ||
4774 | fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); | |
4775 | if (fgd == NULL) | |
4776 | return -ENOMEM; | |
4777 | ||
b9b0c831 NK |
4778 | mutex_lock(&graph_lock); |
4779 | ||
649b988b SRV |
4780 | fgd->hash = rcu_dereference_protected(ftrace_graph_notrace_hash, |
4781 | lockdep_is_held(&graph_lock)); | |
b9b0c831 | 4782 | fgd->type = GRAPH_FILTER_NOTRACE; |
29ad23b0 NK |
4783 | fgd->seq_ops = &ftrace_graph_seq_ops; |
4784 | ||
b9b0c831 NK |
4785 | ret = __ftrace_graph_open(inode, file, fgd); |
4786 | if (ret < 0) | |
4787 | kfree(fgd); | |
4788 | ||
4789 | mutex_unlock(&graph_lock); | |
4790 | return ret; | |
29ad23b0 NK |
4791 | } |
4792 | ||
87827111 LZ |
4793 | static int |
4794 | ftrace_graph_release(struct inode *inode, struct file *file) | |
4795 | { | |
b9b0c831 | 4796 | struct ftrace_graph_data *fgd; |
e704eff3 SRV |
4797 | struct ftrace_hash *old_hash, *new_hash; |
4798 | struct trace_parser *parser; | |
4799 | int ret = 0; | |
b9b0c831 | 4800 | |
faf982a6 NK |
4801 | if (file->f_mode & FMODE_READ) { |
4802 | struct seq_file *m = file->private_data; | |
4803 | ||
b9b0c831 | 4804 | fgd = m->private; |
87827111 | 4805 | seq_release(inode, file); |
faf982a6 | 4806 | } else { |
b9b0c831 | 4807 | fgd = file->private_data; |
faf982a6 NK |
4808 | } |
4809 | ||
e704eff3 SRV |
4810 | |
4811 | if (file->f_mode & FMODE_WRITE) { | |
4812 | ||
4813 | parser = &fgd->parser; | |
4814 | ||
4815 | if (trace_parser_loaded((parser))) { | |
4816 | parser->buffer[parser->idx] = 0; | |
4817 | ret = ftrace_graph_set_hash(fgd->new_hash, | |
4818 | parser->buffer); | |
4819 | } | |
4820 | ||
4821 | trace_parser_put(parser); | |
4822 | ||
4823 | new_hash = __ftrace_hash_move(fgd->new_hash); | |
4824 | if (!new_hash) { | |
4825 | ret = -ENOMEM; | |
4826 | goto out; | |
4827 | } | |
4828 | ||
4829 | mutex_lock(&graph_lock); | |
4830 | ||
4831 | if (fgd->type == GRAPH_FILTER_FUNCTION) { | |
4832 | old_hash = rcu_dereference_protected(ftrace_graph_hash, | |
4833 | lockdep_is_held(&graph_lock)); | |
4834 | rcu_assign_pointer(ftrace_graph_hash, new_hash); | |
4835 | } else { | |
4836 | old_hash = rcu_dereference_protected(ftrace_graph_notrace_hash, | |
4837 | lockdep_is_held(&graph_lock)); | |
4838 | rcu_assign_pointer(ftrace_graph_notrace_hash, new_hash); | |
4839 | } | |
4840 | ||
4841 | mutex_unlock(&graph_lock); | |
4842 | ||
4843 | /* Wait till all users are no longer using the old hash */ | |
4844 | synchronize_sched(); | |
4845 | ||
4846 | free_ftrace_hash(old_hash); | |
4847 | } | |
4848 | ||
4849 | out: | |
b9b0c831 NK |
4850 | kfree(fgd->new_hash); |
4851 | kfree(fgd); | |
4852 | ||
e704eff3 | 4853 | return ret; |
87827111 LZ |
4854 | } |
4855 | ||
ea4e2bc4 | 4856 | static int |
b9b0c831 | 4857 | ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer) |
ea4e2bc4 | 4858 | { |
3ba00929 | 4859 | struct ftrace_glob func_g; |
ea4e2bc4 SR |
4860 | struct dyn_ftrace *rec; |
4861 | struct ftrace_page *pg; | |
b9b0c831 | 4862 | struct ftrace_func_entry *entry; |
c7c6b1fe | 4863 | int fail = 1; |
3ba00929 | 4864 | int not; |
ea4e2bc4 | 4865 | |
f9349a8f | 4866 | /* decode regex */ |
3ba00929 DS |
4867 | func_g.type = filter_parse_regex(buffer, strlen(buffer), |
4868 | &func_g.search, ¬); | |
f9349a8f | 4869 | |
3ba00929 | 4870 | func_g.len = strlen(func_g.search); |
f9349a8f | 4871 | |
52baf119 | 4872 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
4873 | |
4874 | if (unlikely(ftrace_disabled)) { | |
4875 | mutex_unlock(&ftrace_lock); | |
4876 | return -ENODEV; | |
4877 | } | |
4878 | ||
265c831c SR |
4879 | do_for_each_ftrace_rec(pg, rec) { |
4880 | ||
546fece4 SRRH |
4881 | if (rec->flags & FTRACE_FL_DISABLED) |
4882 | continue; | |
4883 | ||
0b507e1e | 4884 | if (ftrace_match_record(rec, &func_g, NULL, 0)) { |
b9b0c831 | 4885 | entry = ftrace_lookup_ip(hash, rec->ip); |
c7c6b1fe LZ |
4886 | |
4887 | if (!not) { | |
4888 | fail = 0; | |
b9b0c831 NK |
4889 | |
4890 | if (entry) | |
4891 | continue; | |
4892 | if (add_hash_entry(hash, rec->ip) < 0) | |
4893 | goto out; | |
c7c6b1fe | 4894 | } else { |
b9b0c831 NK |
4895 | if (entry) { |
4896 | free_hash_entry(hash, entry); | |
c7c6b1fe LZ |
4897 | fail = 0; |
4898 | } | |
4899 | } | |
ea4e2bc4 | 4900 | } |
265c831c | 4901 | } while_for_each_ftrace_rec(); |
c7c6b1fe | 4902 | out: |
52baf119 | 4903 | mutex_unlock(&ftrace_lock); |
ea4e2bc4 | 4904 | |
c7c6b1fe LZ |
4905 | if (fail) |
4906 | return -EINVAL; | |
4907 | ||
c7c6b1fe | 4908 | return 0; |
ea4e2bc4 SR |
4909 | } |
4910 | ||
4911 | static ssize_t | |
4912 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
4913 | size_t cnt, loff_t *ppos) | |
4914 | { | |
6a10108b | 4915 | ssize_t read, ret = 0; |
faf982a6 | 4916 | struct ftrace_graph_data *fgd = file->private_data; |
e704eff3 | 4917 | struct trace_parser *parser; |
ea4e2bc4 | 4918 | |
c7c6b1fe | 4919 | if (!cnt) |
ea4e2bc4 SR |
4920 | return 0; |
4921 | ||
ae98d27a SRV |
4922 | /* Read mode uses seq functions */ |
4923 | if (file->f_mode & FMODE_READ) { | |
4924 | struct seq_file *m = file->private_data; | |
4925 | fgd = m->private; | |
4926 | } | |
4927 | ||
e704eff3 | 4928 | parser = &fgd->parser; |
ea4e2bc4 | 4929 | |
e704eff3 | 4930 | read = trace_get_user(parser, ubuf, cnt, ppos); |
689fd8b6 | 4931 | |
e704eff3 SRV |
4932 | if (read >= 0 && trace_parser_loaded(parser) && |
4933 | !trace_parser_cont(parser)) { | |
6a10108b | 4934 | |
b9b0c831 | 4935 | ret = ftrace_graph_set_hash(fgd->new_hash, |
e704eff3 SRV |
4936 | parser->buffer); |
4937 | trace_parser_clear(parser); | |
ea4e2bc4 | 4938 | } |
ea4e2bc4 | 4939 | |
6a10108b NK |
4940 | if (!ret) |
4941 | ret = read; | |
1eb90f13 | 4942 | |
ea4e2bc4 SR |
4943 | return ret; |
4944 | } | |
4945 | ||
4946 | static const struct file_operations ftrace_graph_fops = { | |
87827111 LZ |
4947 | .open = ftrace_graph_open, |
4948 | .read = seq_read, | |
4949 | .write = ftrace_graph_write, | |
098c879e | 4950 | .llseek = tracing_lseek, |
87827111 | 4951 | .release = ftrace_graph_release, |
ea4e2bc4 | 4952 | }; |
29ad23b0 NK |
4953 | |
4954 | static const struct file_operations ftrace_graph_notrace_fops = { | |
4955 | .open = ftrace_graph_notrace_open, | |
4956 | .read = seq_read, | |
4957 | .write = ftrace_graph_write, | |
098c879e | 4958 | .llseek = tracing_lseek, |
29ad23b0 NK |
4959 | .release = ftrace_graph_release, |
4960 | }; | |
ea4e2bc4 SR |
4961 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
4962 | ||
591dffda SRRH |
4963 | void ftrace_create_filter_files(struct ftrace_ops *ops, |
4964 | struct dentry *parent) | |
4965 | { | |
4966 | ||
4967 | trace_create_file("set_ftrace_filter", 0644, parent, | |
4968 | ops, &ftrace_filter_fops); | |
4969 | ||
4970 | trace_create_file("set_ftrace_notrace", 0644, parent, | |
4971 | ops, &ftrace_notrace_fops); | |
4972 | } | |
4973 | ||
4974 | /* | |
4975 | * The name "destroy_filter_files" is really a misnomer. Although | |
4976 | * in the future, it may actualy delete the files, but this is | |
4977 | * really intended to make sure the ops passed in are disabled | |
4978 | * and that when this function returns, the caller is free to | |
4979 | * free the ops. | |
4980 | * | |
4981 | * The "destroy" name is only to match the "create" name that this | |
4982 | * should be paired with. | |
4983 | */ | |
4984 | void ftrace_destroy_filter_files(struct ftrace_ops *ops) | |
4985 | { | |
4986 | mutex_lock(&ftrace_lock); | |
4987 | if (ops->flags & FTRACE_OPS_FL_ENABLED) | |
4988 | ftrace_shutdown(ops, 0); | |
4989 | ops->flags |= FTRACE_OPS_FL_DELETED; | |
4990 | mutex_unlock(&ftrace_lock); | |
4991 | } | |
4992 | ||
8434dc93 | 4993 | static __init int ftrace_init_dyn_tracefs(struct dentry *d_tracer) |
5072c59f | 4994 | { |
5072c59f | 4995 | |
5452af66 FW |
4996 | trace_create_file("available_filter_functions", 0444, |
4997 | d_tracer, NULL, &ftrace_avail_fops); | |
5072c59f | 4998 | |
647bcd03 SR |
4999 | trace_create_file("enabled_functions", 0444, |
5000 | d_tracer, NULL, &ftrace_enabled_fops); | |
5001 | ||
591dffda | 5002 | ftrace_create_filter_files(&global_ops, d_tracer); |
ad90c0e3 | 5003 | |
ea4e2bc4 | 5004 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5452af66 | 5005 | trace_create_file("set_graph_function", 0444, d_tracer, |
ea4e2bc4 SR |
5006 | NULL, |
5007 | &ftrace_graph_fops); | |
29ad23b0 NK |
5008 | trace_create_file("set_graph_notrace", 0444, d_tracer, |
5009 | NULL, | |
5010 | &ftrace_graph_notrace_fops); | |
ea4e2bc4 SR |
5011 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
5012 | ||
5072c59f SR |
5013 | return 0; |
5014 | } | |
5015 | ||
9fd49328 | 5016 | static int ftrace_cmp_ips(const void *a, const void *b) |
68950619 | 5017 | { |
9fd49328 SR |
5018 | const unsigned long *ipa = a; |
5019 | const unsigned long *ipb = b; | |
68950619 | 5020 | |
9fd49328 SR |
5021 | if (*ipa > *ipb) |
5022 | return 1; | |
5023 | if (*ipa < *ipb) | |
5024 | return -1; | |
5025 | return 0; | |
5026 | } | |
5027 | ||
5cb084bb | 5028 | static int ftrace_process_locs(struct module *mod, |
31e88909 | 5029 | unsigned long *start, |
68bf21aa SR |
5030 | unsigned long *end) |
5031 | { | |
706c81f8 | 5032 | struct ftrace_page *start_pg; |
a7900875 | 5033 | struct ftrace_page *pg; |
706c81f8 | 5034 | struct dyn_ftrace *rec; |
a7900875 | 5035 | unsigned long count; |
68bf21aa SR |
5036 | unsigned long *p; |
5037 | unsigned long addr; | |
4376cac6 | 5038 | unsigned long flags = 0; /* Shut up gcc */ |
a7900875 SR |
5039 | int ret = -ENOMEM; |
5040 | ||
5041 | count = end - start; | |
5042 | ||
5043 | if (!count) | |
5044 | return 0; | |
5045 | ||
9fd49328 | 5046 | sort(start, count, sizeof(*start), |
6db02903 | 5047 | ftrace_cmp_ips, NULL); |
9fd49328 | 5048 | |
706c81f8 SR |
5049 | start_pg = ftrace_allocate_pages(count); |
5050 | if (!start_pg) | |
a7900875 | 5051 | return -ENOMEM; |
68bf21aa | 5052 | |
e6ea44e9 | 5053 | mutex_lock(&ftrace_lock); |
a7900875 | 5054 | |
32082309 SR |
5055 | /* |
5056 | * Core and each module needs their own pages, as | |
5057 | * modules will free them when they are removed. | |
5058 | * Force a new page to be allocated for modules. | |
5059 | */ | |
a7900875 SR |
5060 | if (!mod) { |
5061 | WARN_ON(ftrace_pages || ftrace_pages_start); | |
5062 | /* First initialization */ | |
706c81f8 | 5063 | ftrace_pages = ftrace_pages_start = start_pg; |
a7900875 | 5064 | } else { |
32082309 | 5065 | if (!ftrace_pages) |
a7900875 | 5066 | goto out; |
32082309 | 5067 | |
a7900875 SR |
5068 | if (WARN_ON(ftrace_pages->next)) { |
5069 | /* Hmm, we have free pages? */ | |
5070 | while (ftrace_pages->next) | |
5071 | ftrace_pages = ftrace_pages->next; | |
32082309 | 5072 | } |
a7900875 | 5073 | |
706c81f8 | 5074 | ftrace_pages->next = start_pg; |
32082309 SR |
5075 | } |
5076 | ||
68bf21aa | 5077 | p = start; |
706c81f8 | 5078 | pg = start_pg; |
68bf21aa SR |
5079 | while (p < end) { |
5080 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
5081 | /* |
5082 | * Some architecture linkers will pad between | |
5083 | * the different mcount_loc sections of different | |
5084 | * object files to satisfy alignments. | |
5085 | * Skip any NULL pointers. | |
5086 | */ | |
5087 | if (!addr) | |
5088 | continue; | |
706c81f8 SR |
5089 | |
5090 | if (pg->index == pg->size) { | |
5091 | /* We should have allocated enough */ | |
5092 | if (WARN_ON(!pg->next)) | |
5093 | break; | |
5094 | pg = pg->next; | |
5095 | } | |
5096 | ||
5097 | rec = &pg->records[pg->index++]; | |
5098 | rec->ip = addr; | |
68bf21aa SR |
5099 | } |
5100 | ||
706c81f8 SR |
5101 | /* We should have used all pages */ |
5102 | WARN_ON(pg->next); | |
5103 | ||
5104 | /* Assign the last page to ftrace_pages */ | |
5105 | ftrace_pages = pg; | |
5106 | ||
a4f18ed1 | 5107 | /* |
4376cac6 SR |
5108 | * We only need to disable interrupts on start up |
5109 | * because we are modifying code that an interrupt | |
5110 | * may execute, and the modification is not atomic. | |
5111 | * But for modules, nothing runs the code we modify | |
5112 | * until we are finished with it, and there's no | |
5113 | * reason to cause large interrupt latencies while we do it. | |
a4f18ed1 | 5114 | */ |
4376cac6 SR |
5115 | if (!mod) |
5116 | local_irq_save(flags); | |
1dc43cf0 | 5117 | ftrace_update_code(mod, start_pg); |
4376cac6 SR |
5118 | if (!mod) |
5119 | local_irq_restore(flags); | |
a7900875 SR |
5120 | ret = 0; |
5121 | out: | |
e6ea44e9 | 5122 | mutex_unlock(&ftrace_lock); |
68bf21aa | 5123 | |
a7900875 | 5124 | return ret; |
68bf21aa SR |
5125 | } |
5126 | ||
93eb677d | 5127 | #ifdef CONFIG_MODULES |
32082309 SR |
5128 | |
5129 | #define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next) | |
5130 | ||
b7ffffbb SRRH |
5131 | static int referenced_filters(struct dyn_ftrace *rec) |
5132 | { | |
5133 | struct ftrace_ops *ops; | |
5134 | int cnt = 0; | |
5135 | ||
5136 | for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) { | |
5137 | if (ops_references_rec(ops, rec)) | |
5138 | cnt++; | |
5139 | } | |
5140 | ||
5141 | return cnt; | |
5142 | } | |
5143 | ||
e7247a15 | 5144 | void ftrace_release_mod(struct module *mod) |
93eb677d SR |
5145 | { |
5146 | struct dyn_ftrace *rec; | |
32082309 | 5147 | struct ftrace_page **last_pg; |
93eb677d | 5148 | struct ftrace_page *pg; |
a7900875 | 5149 | int order; |
93eb677d | 5150 | |
45a4a237 SR |
5151 | mutex_lock(&ftrace_lock); |
5152 | ||
e7247a15 | 5153 | if (ftrace_disabled) |
45a4a237 | 5154 | goto out_unlock; |
93eb677d | 5155 | |
32082309 SR |
5156 | /* |
5157 | * Each module has its own ftrace_pages, remove | |
5158 | * them from the list. | |
5159 | */ | |
5160 | last_pg = &ftrace_pages_start; | |
5161 | for (pg = ftrace_pages_start; pg; pg = *last_pg) { | |
5162 | rec = &pg->records[0]; | |
e7247a15 | 5163 | if (within_module_core(rec->ip, mod)) { |
93eb677d | 5164 | /* |
32082309 SR |
5165 | * As core pages are first, the first |
5166 | * page should never be a module page. | |
93eb677d | 5167 | */ |
32082309 SR |
5168 | if (WARN_ON(pg == ftrace_pages_start)) |
5169 | goto out_unlock; | |
5170 | ||
5171 | /* Check if we are deleting the last page */ | |
5172 | if (pg == ftrace_pages) | |
5173 | ftrace_pages = next_to_ftrace_page(last_pg); | |
5174 | ||
5175 | *last_pg = pg->next; | |
a7900875 SR |
5176 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); |
5177 | free_pages((unsigned long)pg->records, order); | |
5178 | kfree(pg); | |
32082309 SR |
5179 | } else |
5180 | last_pg = &pg->next; | |
5181 | } | |
45a4a237 | 5182 | out_unlock: |
93eb677d SR |
5183 | mutex_unlock(&ftrace_lock); |
5184 | } | |
5185 | ||
7dcd182b | 5186 | void ftrace_module_enable(struct module *mod) |
b7ffffbb SRRH |
5187 | { |
5188 | struct dyn_ftrace *rec; | |
5189 | struct ftrace_page *pg; | |
5190 | ||
5191 | mutex_lock(&ftrace_lock); | |
5192 | ||
5193 | if (ftrace_disabled) | |
5194 | goto out_unlock; | |
5195 | ||
5196 | /* | |
5197 | * If the tracing is enabled, go ahead and enable the record. | |
5198 | * | |
5199 | * The reason not to enable the record immediatelly is the | |
5200 | * inherent check of ftrace_make_nop/ftrace_make_call for | |
5201 | * correct previous instructions. Making first the NOP | |
5202 | * conversion puts the module to the correct state, thus | |
5203 | * passing the ftrace_make_call check. | |
5204 | * | |
5205 | * We also delay this to after the module code already set the | |
5206 | * text to read-only, as we now need to set it back to read-write | |
5207 | * so that we can modify the text. | |
5208 | */ | |
5209 | if (ftrace_start_up) | |
5210 | ftrace_arch_code_modify_prepare(); | |
5211 | ||
5212 | do_for_each_ftrace_rec(pg, rec) { | |
5213 | int cnt; | |
5214 | /* | |
5215 | * do_for_each_ftrace_rec() is a double loop. | |
5216 | * module text shares the pg. If a record is | |
5217 | * not part of this module, then skip this pg, | |
5218 | * which the "break" will do. | |
5219 | */ | |
5220 | if (!within_module_core(rec->ip, mod)) | |
5221 | break; | |
5222 | ||
5223 | cnt = 0; | |
5224 | ||
5225 | /* | |
5226 | * When adding a module, we need to check if tracers are | |
5227 | * currently enabled and if they are, and can trace this record, | |
5228 | * we need to enable the module functions as well as update the | |
5229 | * reference counts for those function records. | |
5230 | */ | |
5231 | if (ftrace_start_up) | |
5232 | cnt += referenced_filters(rec); | |
5233 | ||
5234 | /* This clears FTRACE_FL_DISABLED */ | |
5235 | rec->flags = cnt; | |
5236 | ||
5237 | if (ftrace_start_up && cnt) { | |
5238 | int failed = __ftrace_replace_code(rec, 1); | |
5239 | if (failed) { | |
5240 | ftrace_bug(failed, rec); | |
5241 | goto out_loop; | |
5242 | } | |
5243 | } | |
5244 | ||
5245 | } while_for_each_ftrace_rec(); | |
5246 | ||
5247 | out_loop: | |
5248 | if (ftrace_start_up) | |
5249 | ftrace_arch_code_modify_post_process(); | |
5250 | ||
5251 | out_unlock: | |
5252 | mutex_unlock(&ftrace_lock); | |
5253 | } | |
5254 | ||
b6b71f66 | 5255 | void ftrace_module_init(struct module *mod) |
90d595fe | 5256 | { |
97e9b4fc | 5257 | if (ftrace_disabled || !mod->num_ftrace_callsites) |
fed1939c | 5258 | return; |
90d595fe | 5259 | |
97e9b4fc SRRH |
5260 | ftrace_process_locs(mod, mod->ftrace_callsites, |
5261 | mod->ftrace_callsites + mod->num_ftrace_callsites); | |
8c189ea6 | 5262 | } |
93eb677d SR |
5263 | #endif /* CONFIG_MODULES */ |
5264 | ||
68bf21aa SR |
5265 | void __init ftrace_init(void) |
5266 | { | |
1dc43cf0 JS |
5267 | extern unsigned long __start_mcount_loc[]; |
5268 | extern unsigned long __stop_mcount_loc[]; | |
3a36cb11 | 5269 | unsigned long count, flags; |
68bf21aa SR |
5270 | int ret; |
5271 | ||
68bf21aa | 5272 | local_irq_save(flags); |
3a36cb11 | 5273 | ret = ftrace_dyn_arch_init(); |
68bf21aa | 5274 | local_irq_restore(flags); |
af64a7cb | 5275 | if (ret) |
68bf21aa SR |
5276 | goto failed; |
5277 | ||
5278 | count = __stop_mcount_loc - __start_mcount_loc; | |
c867ccd8 JS |
5279 | if (!count) { |
5280 | pr_info("ftrace: No functions to be traced?\n"); | |
68bf21aa | 5281 | goto failed; |
c867ccd8 JS |
5282 | } |
5283 | ||
5284 | pr_info("ftrace: allocating %ld entries in %ld pages\n", | |
5285 | count, count / ENTRIES_PER_PAGE + 1); | |
68bf21aa SR |
5286 | |
5287 | last_ftrace_enabled = ftrace_enabled = 1; | |
5288 | ||
5cb084bb | 5289 | ret = ftrace_process_locs(NULL, |
31e88909 | 5290 | __start_mcount_loc, |
68bf21aa SR |
5291 | __stop_mcount_loc); |
5292 | ||
2af15d6a SR |
5293 | set_ftrace_early_filters(); |
5294 | ||
68bf21aa SR |
5295 | return; |
5296 | failed: | |
5297 | ftrace_disabled = 1; | |
5298 | } | |
68bf21aa | 5299 | |
f3bea491 SRRH |
5300 | /* Do nothing if arch does not support this */ |
5301 | void __weak arch_ftrace_update_trampoline(struct ftrace_ops *ops) | |
5302 | { | |
5303 | } | |
5304 | ||
5305 | static void ftrace_update_trampoline(struct ftrace_ops *ops) | |
5306 | { | |
12cce594 SRRH |
5307 | |
5308 | /* | |
5309 | * Currently there's no safe way to free a trampoline when the kernel | |
5310 | * is configured with PREEMPT. That is because a task could be preempted | |
5311 | * when it jumped to the trampoline, it may be preempted for a long time | |
5312 | * depending on the system load, and currently there's no way to know | |
5313 | * when it will be off the trampoline. If the trampoline is freed | |
5314 | * too early, when the task runs again, it will be executing on freed | |
5315 | * memory and crash. | |
5316 | */ | |
5317 | #ifdef CONFIG_PREEMPT | |
f3bea491 SRRH |
5318 | /* Currently, only non dynamic ops can have a trampoline */ |
5319 | if (ops->flags & FTRACE_OPS_FL_DYNAMIC) | |
5320 | return; | |
12cce594 | 5321 | #endif |
f3bea491 SRRH |
5322 | |
5323 | arch_ftrace_update_trampoline(ops); | |
5324 | } | |
5325 | ||
3d083395 | 5326 | #else |
0b6e4d56 | 5327 | |
2b499381 | 5328 | static struct ftrace_ops global_ops = { |
bd69c30b | 5329 | .func = ftrace_stub, |
e3eea140 SRRH |
5330 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | |
5331 | FTRACE_OPS_FL_INITIALIZED | | |
5332 | FTRACE_OPS_FL_PID, | |
bd69c30b SR |
5333 | }; |
5334 | ||
0b6e4d56 FW |
5335 | static int __init ftrace_nodyn_init(void) |
5336 | { | |
5337 | ftrace_enabled = 1; | |
5338 | return 0; | |
5339 | } | |
6f415672 | 5340 | core_initcall(ftrace_nodyn_init); |
0b6e4d56 | 5341 | |
8434dc93 | 5342 | static inline int ftrace_init_dyn_tracefs(struct dentry *d_tracer) { return 0; } |
df4fc315 | 5343 | static inline void ftrace_startup_enable(int command) { } |
e1effa01 | 5344 | static inline void ftrace_startup_all(int command) { } |
5a45cfe1 | 5345 | /* Keep as macros so we do not need to define the commands */ |
8a56d776 SRRH |
5346 | # define ftrace_startup(ops, command) \ |
5347 | ({ \ | |
5348 | int ___ret = __register_ftrace_function(ops); \ | |
5349 | if (!___ret) \ | |
5350 | (ops)->flags |= FTRACE_OPS_FL_ENABLED; \ | |
5351 | ___ret; \ | |
3b6cfdb1 | 5352 | }) |
1fcc1553 SRRH |
5353 | # define ftrace_shutdown(ops, command) \ |
5354 | ({ \ | |
5355 | int ___ret = __unregister_ftrace_function(ops); \ | |
5356 | if (!___ret) \ | |
5357 | (ops)->flags &= ~FTRACE_OPS_FL_ENABLED; \ | |
5358 | ___ret; \ | |
5359 | }) | |
8a56d776 | 5360 | |
c7aafc54 IM |
5361 | # define ftrace_startup_sysctl() do { } while (0) |
5362 | # define ftrace_shutdown_sysctl() do { } while (0) | |
b848914c SR |
5363 | |
5364 | static inline int | |
195a8afc | 5365 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs) |
b848914c SR |
5366 | { |
5367 | return 1; | |
5368 | } | |
5369 | ||
f3bea491 SRRH |
5370 | static void ftrace_update_trampoline(struct ftrace_ops *ops) |
5371 | { | |
5372 | } | |
5373 | ||
3d083395 SR |
5374 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
5375 | ||
4104d326 SRRH |
5376 | __init void ftrace_init_global_array_ops(struct trace_array *tr) |
5377 | { | |
5378 | tr->ops = &global_ops; | |
5379 | tr->ops->private = tr; | |
5380 | } | |
5381 | ||
5382 | void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func) | |
5383 | { | |
5384 | /* If we filter on pids, update to use the pid function */ | |
5385 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { | |
5386 | if (WARN_ON(tr->ops->func != ftrace_stub)) | |
5387 | printk("ftrace ops had %pS for function\n", | |
5388 | tr->ops->func); | |
4104d326 SRRH |
5389 | } |
5390 | tr->ops->func = func; | |
5391 | tr->ops->private = tr; | |
5392 | } | |
5393 | ||
5394 | void ftrace_reset_array_ops(struct trace_array *tr) | |
5395 | { | |
5396 | tr->ops->func = ftrace_stub; | |
5397 | } | |
5398 | ||
2f5f6ad9 SR |
5399 | static inline void |
5400 | __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 5401 | struct ftrace_ops *ignored, struct pt_regs *regs) |
b848914c | 5402 | { |
cdbe61bf | 5403 | struct ftrace_ops *op; |
edc15caf | 5404 | int bit; |
b848914c | 5405 | |
edc15caf SR |
5406 | bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); |
5407 | if (bit < 0) | |
5408 | return; | |
b1cff0ad | 5409 | |
cdbe61bf SR |
5410 | /* |
5411 | * Some of the ops may be dynamically allocated, | |
5412 | * they must be freed after a synchronize_sched(). | |
5413 | */ | |
5414 | preempt_disable_notrace(); | |
ba27f2bc | 5415 | |
0a016409 | 5416 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
ba27f2bc SRRH |
5417 | /* |
5418 | * Check the following for each ops before calling their func: | |
5419 | * if RCU flag is set, then rcu_is_watching() must be true | |
5420 | * if PER_CPU is set, then ftrace_function_local_disable() | |
5421 | * must be false | |
5422 | * Otherwise test if the ip matches the ops filter | |
5423 | * | |
5424 | * If any of the above fails then the op->func() is not executed. | |
5425 | */ | |
5426 | if ((!(op->flags & FTRACE_OPS_FL_RCU) || rcu_is_watching()) && | |
5427 | (!(op->flags & FTRACE_OPS_FL_PER_CPU) || | |
5428 | !ftrace_function_local_disabled(op)) && | |
5429 | ftrace_ops_test(op, ip, regs)) { | |
5430 | ||
1d48d596 SRRH |
5431 | if (FTRACE_WARN_ON(!op->func)) { |
5432 | pr_warn("op=%p %pS\n", op, op); | |
4104d326 SRRH |
5433 | goto out; |
5434 | } | |
a1e2e31d | 5435 | op->func(ip, parent_ip, op, regs); |
4104d326 | 5436 | } |
0a016409 | 5437 | } while_for_each_ftrace_op(op); |
4104d326 | 5438 | out: |
cdbe61bf | 5439 | preempt_enable_notrace(); |
edc15caf | 5440 | trace_clear_recursion(bit); |
b848914c SR |
5441 | } |
5442 | ||
2f5f6ad9 SR |
5443 | /* |
5444 | * Some archs only support passing ip and parent_ip. Even though | |
5445 | * the list function ignores the op parameter, we do not want any | |
5446 | * C side effects, where a function is called without the caller | |
5447 | * sending a third parameter. | |
a1e2e31d SR |
5448 | * Archs are to support both the regs and ftrace_ops at the same time. |
5449 | * If they support ftrace_ops, it is assumed they support regs. | |
5450 | * If call backs want to use regs, they must either check for regs | |
06aeaaea MH |
5451 | * being NULL, or CONFIG_DYNAMIC_FTRACE_WITH_REGS. |
5452 | * Note, CONFIG_DYNAMIC_FTRACE_WITH_REGS expects a full regs to be saved. | |
a1e2e31d | 5453 | * An architecture can pass partial regs with ftrace_ops and still |
b8ec330a | 5454 | * set the ARCH_SUPPORTS_FTRACE_OPS. |
2f5f6ad9 SR |
5455 | */ |
5456 | #if ARCH_SUPPORTS_FTRACE_OPS | |
5457 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 5458 | struct ftrace_ops *op, struct pt_regs *regs) |
2f5f6ad9 | 5459 | { |
a1e2e31d | 5460 | __ftrace_ops_list_func(ip, parent_ip, NULL, regs); |
2f5f6ad9 SR |
5461 | } |
5462 | #else | |
5463 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip) | |
5464 | { | |
a1e2e31d | 5465 | __ftrace_ops_list_func(ip, parent_ip, NULL, NULL); |
2f5f6ad9 SR |
5466 | } |
5467 | #endif | |
5468 | ||
f1ff6348 SRRH |
5469 | /* |
5470 | * If there's only one function registered but it does not support | |
c68c0fa2 SRRH |
5471 | * recursion, needs RCU protection and/or requires per cpu handling, then |
5472 | * this function will be called by the mcount trampoline. | |
f1ff6348 | 5473 | */ |
c68c0fa2 | 5474 | static void ftrace_ops_assist_func(unsigned long ip, unsigned long parent_ip, |
f1ff6348 SRRH |
5475 | struct ftrace_ops *op, struct pt_regs *regs) |
5476 | { | |
5477 | int bit; | |
5478 | ||
c68c0fa2 SRRH |
5479 | if ((op->flags & FTRACE_OPS_FL_RCU) && !rcu_is_watching()) |
5480 | return; | |
5481 | ||
f1ff6348 SRRH |
5482 | bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); |
5483 | if (bit < 0) | |
5484 | return; | |
5485 | ||
c68c0fa2 | 5486 | preempt_disable_notrace(); |
f1ff6348 | 5487 | |
c68c0fa2 SRRH |
5488 | if (!(op->flags & FTRACE_OPS_FL_PER_CPU) || |
5489 | !ftrace_function_local_disabled(op)) { | |
5490 | op->func(ip, parent_ip, op, regs); | |
5491 | } | |
5492 | ||
5493 | preempt_enable_notrace(); | |
f1ff6348 SRRH |
5494 | trace_clear_recursion(bit); |
5495 | } | |
5496 | ||
87354059 SRRH |
5497 | /** |
5498 | * ftrace_ops_get_func - get the function a trampoline should call | |
5499 | * @ops: the ops to get the function for | |
5500 | * | |
5501 | * Normally the mcount trampoline will call the ops->func, but there | |
5502 | * are times that it should not. For example, if the ops does not | |
5503 | * have its own recursion protection, then it should call the | |
3a150df9 | 5504 | * ftrace_ops_assist_func() instead. |
87354059 SRRH |
5505 | * |
5506 | * Returns the function that the trampoline should call for @ops. | |
5507 | */ | |
5508 | ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops) | |
5509 | { | |
87354059 | 5510 | /* |
c68c0fa2 SRRH |
5511 | * If the function does not handle recursion, needs to be RCU safe, |
5512 | * or does per cpu logic, then we need to call the assist handler. | |
87354059 | 5513 | */ |
c68c0fa2 SRRH |
5514 | if (!(ops->flags & FTRACE_OPS_FL_RECURSION_SAFE) || |
5515 | ops->flags & (FTRACE_OPS_FL_RCU | FTRACE_OPS_FL_PER_CPU)) | |
5516 | return ftrace_ops_assist_func; | |
87354059 SRRH |
5517 | |
5518 | return ops->func; | |
5519 | } | |
5520 | ||
345ddcc8 SRRH |
5521 | static void |
5522 | ftrace_filter_pid_sched_switch_probe(void *data, bool preempt, | |
5523 | struct task_struct *prev, struct task_struct *next) | |
978f3a45 | 5524 | { |
345ddcc8 SRRH |
5525 | struct trace_array *tr = data; |
5526 | struct trace_pid_list *pid_list; | |
978f3a45 | 5527 | |
345ddcc8 | 5528 | pid_list = rcu_dereference_sched(tr->function_pids); |
e32d8956 | 5529 | |
345ddcc8 SRRH |
5530 | this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid, |
5531 | trace_ignore_this_task(pid_list, next)); | |
978f3a45 SR |
5532 | } |
5533 | ||
345ddcc8 | 5534 | static void clear_ftrace_pids(struct trace_array *tr) |
e32d8956 | 5535 | { |
345ddcc8 SRRH |
5536 | struct trace_pid_list *pid_list; |
5537 | int cpu; | |
e32d8956 | 5538 | |
345ddcc8 SRRH |
5539 | pid_list = rcu_dereference_protected(tr->function_pids, |
5540 | lockdep_is_held(&ftrace_lock)); | |
5541 | if (!pid_list) | |
5542 | return; | |
229c4ef8 | 5543 | |
345ddcc8 | 5544 | unregister_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr); |
e32d8956 | 5545 | |
345ddcc8 SRRH |
5546 | for_each_possible_cpu(cpu) |
5547 | per_cpu_ptr(tr->trace_buffer.data, cpu)->ftrace_ignore_pid = false; | |
978f3a45 | 5548 | |
345ddcc8 | 5549 | rcu_assign_pointer(tr->function_pids, NULL); |
978f3a45 | 5550 | |
345ddcc8 SRRH |
5551 | /* Wait till all users are no longer using pid filtering */ |
5552 | synchronize_sched(); | |
e32d8956 | 5553 | |
345ddcc8 | 5554 | trace_free_pid_list(pid_list); |
e32d8956 SR |
5555 | } |
5556 | ||
345ddcc8 | 5557 | static void ftrace_pid_reset(struct trace_array *tr) |
df4fc315 | 5558 | { |
756d17ee | 5559 | mutex_lock(&ftrace_lock); |
345ddcc8 | 5560 | clear_ftrace_pids(tr); |
978f3a45 | 5561 | |
756d17ee | 5562 | ftrace_update_pid_func(); |
e1effa01 | 5563 | ftrace_startup_all(0); |
756d17ee | 5564 | |
5565 | mutex_unlock(&ftrace_lock); | |
756d17ee | 5566 | } |
5567 | ||
345ddcc8 SRRH |
5568 | /* Greater than any max PID */ |
5569 | #define FTRACE_NO_PIDS (void *)(PID_MAX_LIMIT + 1) | |
df4fc315 | 5570 | |
756d17ee | 5571 | static void *fpid_start(struct seq_file *m, loff_t *pos) |
345ddcc8 | 5572 | __acquires(RCU) |
756d17ee | 5573 | { |
345ddcc8 SRRH |
5574 | struct trace_pid_list *pid_list; |
5575 | struct trace_array *tr = m->private; | |
5576 | ||
756d17ee | 5577 | mutex_lock(&ftrace_lock); |
345ddcc8 SRRH |
5578 | rcu_read_lock_sched(); |
5579 | ||
5580 | pid_list = rcu_dereference_sched(tr->function_pids); | |
756d17ee | 5581 | |
345ddcc8 SRRH |
5582 | if (!pid_list) |
5583 | return !(*pos) ? FTRACE_NO_PIDS : NULL; | |
756d17ee | 5584 | |
345ddcc8 | 5585 | return trace_pid_start(pid_list, pos); |
756d17ee | 5586 | } |
5587 | ||
5588 | static void *fpid_next(struct seq_file *m, void *v, loff_t *pos) | |
5589 | { | |
345ddcc8 SRRH |
5590 | struct trace_array *tr = m->private; |
5591 | struct trace_pid_list *pid_list = rcu_dereference_sched(tr->function_pids); | |
5592 | ||
5593 | if (v == FTRACE_NO_PIDS) | |
756d17ee | 5594 | return NULL; |
5595 | ||
345ddcc8 | 5596 | return trace_pid_next(pid_list, v, pos); |
756d17ee | 5597 | } |
5598 | ||
5599 | static void fpid_stop(struct seq_file *m, void *p) | |
345ddcc8 | 5600 | __releases(RCU) |
756d17ee | 5601 | { |
345ddcc8 | 5602 | rcu_read_unlock_sched(); |
756d17ee | 5603 | mutex_unlock(&ftrace_lock); |
5604 | } | |
5605 | ||
5606 | static int fpid_show(struct seq_file *m, void *v) | |
5607 | { | |
345ddcc8 | 5608 | if (v == FTRACE_NO_PIDS) { |
fa6f0cc7 | 5609 | seq_puts(m, "no pid\n"); |
756d17ee | 5610 | return 0; |
5611 | } | |
5612 | ||
345ddcc8 | 5613 | return trace_pid_show(m, v); |
756d17ee | 5614 | } |
5615 | ||
5616 | static const struct seq_operations ftrace_pid_sops = { | |
5617 | .start = fpid_start, | |
5618 | .next = fpid_next, | |
5619 | .stop = fpid_stop, | |
5620 | .show = fpid_show, | |
5621 | }; | |
5622 | ||
5623 | static int | |
5624 | ftrace_pid_open(struct inode *inode, struct file *file) | |
5625 | { | |
345ddcc8 SRRH |
5626 | struct trace_array *tr = inode->i_private; |
5627 | struct seq_file *m; | |
756d17ee | 5628 | int ret = 0; |
5629 | ||
345ddcc8 SRRH |
5630 | if (trace_array_get(tr) < 0) |
5631 | return -ENODEV; | |
5632 | ||
756d17ee | 5633 | if ((file->f_mode & FMODE_WRITE) && |
5634 | (file->f_flags & O_TRUNC)) | |
345ddcc8 | 5635 | ftrace_pid_reset(tr); |
756d17ee | 5636 | |
345ddcc8 SRRH |
5637 | ret = seq_open(file, &ftrace_pid_sops); |
5638 | if (ret < 0) { | |
5639 | trace_array_put(tr); | |
5640 | } else { | |
5641 | m = file->private_data; | |
5642 | /* copy tr over to seq ops */ | |
5643 | m->private = tr; | |
5644 | } | |
756d17ee | 5645 | |
5646 | return ret; | |
5647 | } | |
5648 | ||
345ddcc8 SRRH |
5649 | static void ignore_task_cpu(void *data) |
5650 | { | |
5651 | struct trace_array *tr = data; | |
5652 | struct trace_pid_list *pid_list; | |
5653 | ||
5654 | /* | |
5655 | * This function is called by on_each_cpu() while the | |
5656 | * event_mutex is held. | |
5657 | */ | |
5658 | pid_list = rcu_dereference_protected(tr->function_pids, | |
5659 | mutex_is_locked(&ftrace_lock)); | |
5660 | ||
5661 | this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid, | |
5662 | trace_ignore_this_task(pid_list, current)); | |
5663 | } | |
5664 | ||
df4fc315 SR |
5665 | static ssize_t |
5666 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
5667 | size_t cnt, loff_t *ppos) | |
5668 | { | |
345ddcc8 SRRH |
5669 | struct seq_file *m = filp->private_data; |
5670 | struct trace_array *tr = m->private; | |
5671 | struct trace_pid_list *filtered_pids = NULL; | |
5672 | struct trace_pid_list *pid_list; | |
5673 | ssize_t ret; | |
df4fc315 | 5674 | |
345ddcc8 SRRH |
5675 | if (!cnt) |
5676 | return 0; | |
5677 | ||
5678 | mutex_lock(&ftrace_lock); | |
5679 | ||
5680 | filtered_pids = rcu_dereference_protected(tr->function_pids, | |
5681 | lockdep_is_held(&ftrace_lock)); | |
5682 | ||
5683 | ret = trace_pid_write(filtered_pids, &pid_list, ubuf, cnt); | |
5684 | if (ret < 0) | |
5685 | goto out; | |
df4fc315 | 5686 | |
345ddcc8 | 5687 | rcu_assign_pointer(tr->function_pids, pid_list); |
df4fc315 | 5688 | |
345ddcc8 SRRH |
5689 | if (filtered_pids) { |
5690 | synchronize_sched(); | |
5691 | trace_free_pid_list(filtered_pids); | |
5692 | } else if (pid_list) { | |
5693 | /* Register a probe to set whether to ignore the tracing of a task */ | |
5694 | register_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr); | |
5695 | } | |
df4fc315 | 5696 | |
756d17ee | 5697 | /* |
345ddcc8 SRRH |
5698 | * Ignoring of pids is done at task switch. But we have to |
5699 | * check for those tasks that are currently running. | |
5700 | * Always do this in case a pid was appended or removed. | |
756d17ee | 5701 | */ |
345ddcc8 | 5702 | on_each_cpu(ignore_task_cpu, tr, 1); |
756d17ee | 5703 | |
345ddcc8 SRRH |
5704 | ftrace_update_pid_func(); |
5705 | ftrace_startup_all(0); | |
5706 | out: | |
5707 | mutex_unlock(&ftrace_lock); | |
df4fc315 | 5708 | |
345ddcc8 SRRH |
5709 | if (ret > 0) |
5710 | *ppos += ret; | |
df4fc315 | 5711 | |
345ddcc8 | 5712 | return ret; |
756d17ee | 5713 | } |
df4fc315 | 5714 | |
756d17ee | 5715 | static int |
5716 | ftrace_pid_release(struct inode *inode, struct file *file) | |
5717 | { | |
345ddcc8 | 5718 | struct trace_array *tr = inode->i_private; |
df4fc315 | 5719 | |
345ddcc8 SRRH |
5720 | trace_array_put(tr); |
5721 | ||
5722 | return seq_release(inode, file); | |
df4fc315 SR |
5723 | } |
5724 | ||
5e2336a0 | 5725 | static const struct file_operations ftrace_pid_fops = { |
756d17ee | 5726 | .open = ftrace_pid_open, |
5727 | .write = ftrace_pid_write, | |
5728 | .read = seq_read, | |
098c879e | 5729 | .llseek = tracing_lseek, |
756d17ee | 5730 | .release = ftrace_pid_release, |
df4fc315 SR |
5731 | }; |
5732 | ||
345ddcc8 | 5733 | void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
df4fc315 | 5734 | { |
5452af66 | 5735 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
345ddcc8 | 5736 | tr, &ftrace_pid_fops); |
df4fc315 | 5737 | } |
df4fc315 | 5738 | |
501c2375 SRRH |
5739 | void __init ftrace_init_tracefs_toplevel(struct trace_array *tr, |
5740 | struct dentry *d_tracer) | |
5741 | { | |
5742 | /* Only the top level directory has the dyn_tracefs and profile */ | |
5743 | WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); | |
5744 | ||
5745 | ftrace_init_dyn_tracefs(d_tracer); | |
5746 | ftrace_profile_tracefs(d_tracer); | |
5747 | } | |
5748 | ||
a2bb6a3d | 5749 | /** |
81adbdc0 | 5750 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
5751 | * |
5752 | * This function should be used by panic code. It stops ftrace | |
5753 | * but in a not so nice way. If you need to simply kill ftrace | |
5754 | * from a non-atomic section, use ftrace_kill. | |
5755 | */ | |
81adbdc0 | 5756 | void ftrace_kill(void) |
a2bb6a3d SR |
5757 | { |
5758 | ftrace_disabled = 1; | |
5759 | ftrace_enabled = 0; | |
a2bb6a3d SR |
5760 | clear_ftrace_function(); |
5761 | } | |
5762 | ||
e0a413f6 SR |
5763 | /** |
5764 | * Test if ftrace is dead or not. | |
5765 | */ | |
5766 | int ftrace_is_dead(void) | |
5767 | { | |
5768 | return ftrace_disabled; | |
5769 | } | |
5770 | ||
16444a8a | 5771 | /** |
3d083395 SR |
5772 | * register_ftrace_function - register a function for profiling |
5773 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 5774 | * |
3d083395 SR |
5775 | * Register a function to be called by all functions in the |
5776 | * kernel. | |
5777 | * | |
5778 | * Note: @ops->func and all the functions it calls must be labeled | |
5779 | * with "notrace", otherwise it will go into a | |
5780 | * recursive loop. | |
16444a8a | 5781 | */ |
3d083395 | 5782 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 5783 | { |
45a4a237 | 5784 | int ret = -1; |
4eebcc81 | 5785 | |
f04f24fb MH |
5786 | ftrace_ops_init(ops); |
5787 | ||
e6ea44e9 | 5788 | mutex_lock(&ftrace_lock); |
e7d3737e | 5789 | |
8a56d776 | 5790 | ret = ftrace_startup(ops, 0); |
b848914c | 5791 | |
e6ea44e9 | 5792 | mutex_unlock(&ftrace_lock); |
8d240dd8 | 5793 | |
b0fc494f | 5794 | return ret; |
3d083395 | 5795 | } |
cdbe61bf | 5796 | EXPORT_SYMBOL_GPL(register_ftrace_function); |
3d083395 SR |
5797 | |
5798 | /** | |
32632920 | 5799 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
5800 | * @ops - ops structure that holds the function to unregister |
5801 | * | |
5802 | * Unregister a function that was added to be called by ftrace profiling. | |
5803 | */ | |
5804 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
5805 | { | |
5806 | int ret; | |
5807 | ||
e6ea44e9 | 5808 | mutex_lock(&ftrace_lock); |
8a56d776 | 5809 | ret = ftrace_shutdown(ops, 0); |
e6ea44e9 | 5810 | mutex_unlock(&ftrace_lock); |
b0fc494f SR |
5811 | |
5812 | return ret; | |
5813 | } | |
cdbe61bf | 5814 | EXPORT_SYMBOL_GPL(unregister_ftrace_function); |
b0fc494f | 5815 | |
e309b41d | 5816 | int |
b0fc494f | 5817 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
8d65af78 | 5818 | void __user *buffer, size_t *lenp, |
b0fc494f SR |
5819 | loff_t *ppos) |
5820 | { | |
45a4a237 | 5821 | int ret = -ENODEV; |
4eebcc81 | 5822 | |
e6ea44e9 | 5823 | mutex_lock(&ftrace_lock); |
b0fc494f | 5824 | |
45a4a237 SR |
5825 | if (unlikely(ftrace_disabled)) |
5826 | goto out; | |
5827 | ||
5828 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
b0fc494f | 5829 | |
a32c7765 | 5830 | if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) |
b0fc494f SR |
5831 | goto out; |
5832 | ||
a32c7765 | 5833 | last_ftrace_enabled = !!ftrace_enabled; |
b0fc494f SR |
5834 | |
5835 | if (ftrace_enabled) { | |
5836 | ||
b0fc494f | 5837 | /* we are starting ftrace again */ |
5000c418 JK |
5838 | if (ftrace_ops_list != &ftrace_list_end) |
5839 | update_ftrace_function(); | |
b0fc494f | 5840 | |
524a3868 SRRH |
5841 | ftrace_startup_sysctl(); |
5842 | ||
b0fc494f SR |
5843 | } else { |
5844 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
5845 | ftrace_trace_function = ftrace_stub; | |
5846 | ||
5847 | ftrace_shutdown_sysctl(); | |
5848 | } | |
5849 | ||
5850 | out: | |
e6ea44e9 | 5851 | mutex_unlock(&ftrace_lock); |
3d083395 | 5852 | return ret; |
16444a8a | 5853 | } |
f17845e5 | 5854 | |
fb52607a | 5855 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 5856 | |
5f151b24 SRRH |
5857 | static struct ftrace_ops graph_ops = { |
5858 | .func = ftrace_stub, | |
5859 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | | |
5860 | FTRACE_OPS_FL_INITIALIZED | | |
e3eea140 | 5861 | FTRACE_OPS_FL_PID | |
5f151b24 SRRH |
5862 | FTRACE_OPS_FL_STUB, |
5863 | #ifdef FTRACE_GRAPH_TRAMP_ADDR | |
5864 | .trampoline = FTRACE_GRAPH_TRAMP_ADDR, | |
aec0be2d | 5865 | /* trampoline_size is only needed for dynamically allocated tramps */ |
5f151b24 SRRH |
5866 | #endif |
5867 | ASSIGN_OPS_HASH(graph_ops, &global_ops.local_hash) | |
5868 | }; | |
5869 | ||
55577204 SRRH |
5870 | void ftrace_graph_sleep_time_control(bool enable) |
5871 | { | |
5872 | fgraph_sleep_time = enable; | |
5873 | } | |
5874 | ||
5875 | void ftrace_graph_graph_time_control(bool enable) | |
5876 | { | |
5877 | fgraph_graph_time = enable; | |
5878 | } | |
5879 | ||
e49dc19c SR |
5880 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
5881 | { | |
5882 | return 0; | |
5883 | } | |
5884 | ||
287b6e68 FW |
5885 | /* The callbacks that hook a function */ |
5886 | trace_func_graph_ret_t ftrace_graph_return = | |
5887 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 5888 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
23a8e844 | 5889 | static trace_func_graph_ent_t __ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
5890 | |
5891 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
5892 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
5893 | { | |
5894 | int i; | |
5895 | int ret = 0; | |
f201ae23 FW |
5896 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; |
5897 | struct task_struct *g, *t; | |
5898 | ||
5899 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
5900 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
5901 | * sizeof(struct ftrace_ret_stack), | |
5902 | GFP_KERNEL); | |
5903 | if (!ret_stack_list[i]) { | |
5904 | start = 0; | |
5905 | end = i; | |
5906 | ret = -ENOMEM; | |
5907 | goto free; | |
5908 | } | |
5909 | } | |
5910 | ||
6112a300 | 5911 | read_lock(&tasklist_lock); |
f201ae23 FW |
5912 | do_each_thread(g, t) { |
5913 | if (start == end) { | |
5914 | ret = -EAGAIN; | |
5915 | goto unlock; | |
5916 | } | |
5917 | ||
5918 | if (t->ret_stack == NULL) { | |
380c4b14 | 5919 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 | 5920 | atomic_set(&t->trace_overrun, 0); |
26c01624 SR |
5921 | t->curr_ret_stack = -1; |
5922 | /* Make sure the tasks see the -1 first: */ | |
5923 | smp_wmb(); | |
5924 | t->ret_stack = ret_stack_list[start++]; | |
f201ae23 FW |
5925 | } |
5926 | } while_each_thread(g, t); | |
5927 | ||
5928 | unlock: | |
6112a300 | 5929 | read_unlock(&tasklist_lock); |
f201ae23 FW |
5930 | free: |
5931 | for (i = start; i < end; i++) | |
5932 | kfree(ret_stack_list[i]); | |
5933 | return ret; | |
5934 | } | |
5935 | ||
8aef2d28 | 5936 | static void |
c73464b1 | 5937 | ftrace_graph_probe_sched_switch(void *ignore, bool preempt, |
38516ab5 | 5938 | struct task_struct *prev, struct task_struct *next) |
8aef2d28 SR |
5939 | { |
5940 | unsigned long long timestamp; | |
5941 | int index; | |
5942 | ||
be6f164a SR |
5943 | /* |
5944 | * Does the user want to count the time a function was asleep. | |
5945 | * If so, do not update the time stamps. | |
5946 | */ | |
55577204 | 5947 | if (fgraph_sleep_time) |
be6f164a SR |
5948 | return; |
5949 | ||
8aef2d28 SR |
5950 | timestamp = trace_clock_local(); |
5951 | ||
5952 | prev->ftrace_timestamp = timestamp; | |
5953 | ||
5954 | /* only process tasks that we timestamped */ | |
5955 | if (!next->ftrace_timestamp) | |
5956 | return; | |
5957 | ||
5958 | /* | |
5959 | * Update all the counters in next to make up for the | |
5960 | * time next was sleeping. | |
5961 | */ | |
5962 | timestamp -= next->ftrace_timestamp; | |
5963 | ||
5964 | for (index = next->curr_ret_stack; index >= 0; index--) | |
5965 | next->ret_stack[index].calltime += timestamp; | |
5966 | } | |
5967 | ||
f201ae23 | 5968 | /* Allocate a return stack for each task */ |
fb52607a | 5969 | static int start_graph_tracing(void) |
f201ae23 FW |
5970 | { |
5971 | struct ftrace_ret_stack **ret_stack_list; | |
5b058bcd | 5972 | int ret, cpu; |
f201ae23 FW |
5973 | |
5974 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
5975 | sizeof(struct ftrace_ret_stack *), | |
5976 | GFP_KERNEL); | |
5977 | ||
5978 | if (!ret_stack_list) | |
5979 | return -ENOMEM; | |
5980 | ||
5b058bcd | 5981 | /* The cpu_boot init_task->ret_stack will never be freed */ |
179c498a SR |
5982 | for_each_online_cpu(cpu) { |
5983 | if (!idle_task(cpu)->ret_stack) | |
868baf07 | 5984 | ftrace_graph_init_idle_task(idle_task(cpu), cpu); |
179c498a | 5985 | } |
5b058bcd | 5986 | |
f201ae23 FW |
5987 | do { |
5988 | ret = alloc_retstack_tasklist(ret_stack_list); | |
5989 | } while (ret == -EAGAIN); | |
5990 | ||
8aef2d28 | 5991 | if (!ret) { |
38516ab5 | 5992 | ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
8aef2d28 SR |
5993 | if (ret) |
5994 | pr_info("ftrace_graph: Couldn't activate tracepoint" | |
5995 | " probe to kernel_sched_switch\n"); | |
5996 | } | |
5997 | ||
f201ae23 FW |
5998 | kfree(ret_stack_list); |
5999 | return ret; | |
6000 | } | |
6001 | ||
4a2b8dda FW |
6002 | /* |
6003 | * Hibernation protection. | |
6004 | * The state of the current task is too much unstable during | |
6005 | * suspend/restore to disk. We want to protect against that. | |
6006 | */ | |
6007 | static int | |
6008 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, | |
6009 | void *unused) | |
6010 | { | |
6011 | switch (state) { | |
6012 | case PM_HIBERNATION_PREPARE: | |
6013 | pause_graph_tracing(); | |
6014 | break; | |
6015 | ||
6016 | case PM_POST_HIBERNATION: | |
6017 | unpause_graph_tracing(); | |
6018 | break; | |
6019 | } | |
6020 | return NOTIFY_DONE; | |
6021 | } | |
6022 | ||
23a8e844 SRRH |
6023 | static int ftrace_graph_entry_test(struct ftrace_graph_ent *trace) |
6024 | { | |
6025 | if (!ftrace_ops_test(&global_ops, trace->func, NULL)) | |
6026 | return 0; | |
6027 | return __ftrace_graph_entry(trace); | |
6028 | } | |
6029 | ||
6030 | /* | |
6031 | * The function graph tracer should only trace the functions defined | |
6032 | * by set_ftrace_filter and set_ftrace_notrace. If another function | |
6033 | * tracer ops is registered, the graph tracer requires testing the | |
6034 | * function against the global ops, and not just trace any function | |
6035 | * that any ftrace_ops registered. | |
6036 | */ | |
6037 | static void update_function_graph_func(void) | |
6038 | { | |
5f151b24 SRRH |
6039 | struct ftrace_ops *op; |
6040 | bool do_test = false; | |
6041 | ||
6042 | /* | |
6043 | * The graph and global ops share the same set of functions | |
6044 | * to test. If any other ops is on the list, then | |
6045 | * the graph tracing needs to test if its the function | |
6046 | * it should call. | |
6047 | */ | |
6048 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
6049 | if (op != &global_ops && op != &graph_ops && | |
6050 | op != &ftrace_list_end) { | |
6051 | do_test = true; | |
6052 | /* in double loop, break out with goto */ | |
6053 | goto out; | |
6054 | } | |
6055 | } while_for_each_ftrace_op(op); | |
6056 | out: | |
6057 | if (do_test) | |
23a8e844 | 6058 | ftrace_graph_entry = ftrace_graph_entry_test; |
5f151b24 SRRH |
6059 | else |
6060 | ftrace_graph_entry = __ftrace_graph_entry; | |
23a8e844 SRRH |
6061 | } |
6062 | ||
8275f69f MK |
6063 | static struct notifier_block ftrace_suspend_notifier = { |
6064 | .notifier_call = ftrace_suspend_notifier_call, | |
6065 | }; | |
6066 | ||
287b6e68 FW |
6067 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
6068 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 6069 | { |
e7d3737e FW |
6070 | int ret = 0; |
6071 | ||
e6ea44e9 | 6072 | mutex_lock(&ftrace_lock); |
e7d3737e | 6073 | |
05ce5818 | 6074 | /* we currently allow only one tracer registered at a time */ |
597af815 | 6075 | if (ftrace_graph_active) { |
05ce5818 SR |
6076 | ret = -EBUSY; |
6077 | goto out; | |
6078 | } | |
6079 | ||
4a2b8dda FW |
6080 | register_pm_notifier(&ftrace_suspend_notifier); |
6081 | ||
597af815 | 6082 | ftrace_graph_active++; |
fb52607a | 6083 | ret = start_graph_tracing(); |
f201ae23 | 6084 | if (ret) { |
597af815 | 6085 | ftrace_graph_active--; |
f201ae23 FW |
6086 | goto out; |
6087 | } | |
e53a6319 | 6088 | |
287b6e68 | 6089 | ftrace_graph_return = retfunc; |
23a8e844 SRRH |
6090 | |
6091 | /* | |
6092 | * Update the indirect function to the entryfunc, and the | |
6093 | * function that gets called to the entry_test first. Then | |
6094 | * call the update fgraph entry function to determine if | |
6095 | * the entryfunc should be called directly or not. | |
6096 | */ | |
6097 | __ftrace_graph_entry = entryfunc; | |
6098 | ftrace_graph_entry = ftrace_graph_entry_test; | |
6099 | update_function_graph_func(); | |
e53a6319 | 6100 | |
5f151b24 | 6101 | ret = ftrace_startup(&graph_ops, FTRACE_START_FUNC_RET); |
e7d3737e | 6102 | out: |
e6ea44e9 | 6103 | mutex_unlock(&ftrace_lock); |
e7d3737e | 6104 | return ret; |
15e6cb36 FW |
6105 | } |
6106 | ||
fb52607a | 6107 | void unregister_ftrace_graph(void) |
15e6cb36 | 6108 | { |
e6ea44e9 | 6109 | mutex_lock(&ftrace_lock); |
e7d3737e | 6110 | |
597af815 | 6111 | if (unlikely(!ftrace_graph_active)) |
2aad1b76 SR |
6112 | goto out; |
6113 | ||
597af815 | 6114 | ftrace_graph_active--; |
287b6e68 | 6115 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; |
e49dc19c | 6116 | ftrace_graph_entry = ftrace_graph_entry_stub; |
23a8e844 | 6117 | __ftrace_graph_entry = ftrace_graph_entry_stub; |
5f151b24 | 6118 | ftrace_shutdown(&graph_ops, FTRACE_STOP_FUNC_RET); |
4a2b8dda | 6119 | unregister_pm_notifier(&ftrace_suspend_notifier); |
38516ab5 | 6120 | unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
e7d3737e | 6121 | |
f3bea491 SRRH |
6122 | #ifdef CONFIG_DYNAMIC_FTRACE |
6123 | /* | |
6124 | * Function graph does not allocate the trampoline, but | |
6125 | * other global_ops do. We need to reset the ALLOC_TRAMP flag | |
6126 | * if one was used. | |
6127 | */ | |
6128 | global_ops.trampoline = save_global_trampoline; | |
6129 | if (save_global_flags & FTRACE_OPS_FL_ALLOC_TRAMP) | |
6130 | global_ops.flags |= FTRACE_OPS_FL_ALLOC_TRAMP; | |
6131 | #endif | |
6132 | ||
2aad1b76 | 6133 | out: |
e6ea44e9 | 6134 | mutex_unlock(&ftrace_lock); |
15e6cb36 | 6135 | } |
f201ae23 | 6136 | |
868baf07 SR |
6137 | static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack); |
6138 | ||
6139 | static void | |
6140 | graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack) | |
6141 | { | |
6142 | atomic_set(&t->tracing_graph_pause, 0); | |
6143 | atomic_set(&t->trace_overrun, 0); | |
6144 | t->ftrace_timestamp = 0; | |
25985edc | 6145 | /* make curr_ret_stack visible before we add the ret_stack */ |
868baf07 SR |
6146 | smp_wmb(); |
6147 | t->ret_stack = ret_stack; | |
6148 | } | |
6149 | ||
6150 | /* | |
6151 | * Allocate a return stack for the idle task. May be the first | |
6152 | * time through, or it may be done by CPU hotplug online. | |
6153 | */ | |
6154 | void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) | |
6155 | { | |
6156 | t->curr_ret_stack = -1; | |
6157 | /* | |
6158 | * The idle task has no parent, it either has its own | |
6159 | * stack or no stack at all. | |
6160 | */ | |
6161 | if (t->ret_stack) | |
6162 | WARN_ON(t->ret_stack != per_cpu(idle_ret_stack, cpu)); | |
6163 | ||
6164 | if (ftrace_graph_active) { | |
6165 | struct ftrace_ret_stack *ret_stack; | |
6166 | ||
6167 | ret_stack = per_cpu(idle_ret_stack, cpu); | |
6168 | if (!ret_stack) { | |
6169 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
6170 | * sizeof(struct ftrace_ret_stack), | |
6171 | GFP_KERNEL); | |
6172 | if (!ret_stack) | |
6173 | return; | |
6174 | per_cpu(idle_ret_stack, cpu) = ret_stack; | |
6175 | } | |
6176 | graph_init_task(t, ret_stack); | |
6177 | } | |
6178 | } | |
6179 | ||
f201ae23 | 6180 | /* Allocate a return stack for newly created task */ |
fb52607a | 6181 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 6182 | { |
84047e36 SR |
6183 | /* Make sure we do not use the parent ret_stack */ |
6184 | t->ret_stack = NULL; | |
ea14eb71 | 6185 | t->curr_ret_stack = -1; |
84047e36 | 6186 | |
597af815 | 6187 | if (ftrace_graph_active) { |
82310a32 SR |
6188 | struct ftrace_ret_stack *ret_stack; |
6189 | ||
6190 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
f201ae23 FW |
6191 | * sizeof(struct ftrace_ret_stack), |
6192 | GFP_KERNEL); | |
82310a32 | 6193 | if (!ret_stack) |
f201ae23 | 6194 | return; |
868baf07 | 6195 | graph_init_task(t, ret_stack); |
84047e36 | 6196 | } |
f201ae23 FW |
6197 | } |
6198 | ||
fb52607a | 6199 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 6200 | { |
eae849ca FW |
6201 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
6202 | ||
f201ae23 | 6203 | t->ret_stack = NULL; |
eae849ca FW |
6204 | /* NULL must become visible to IRQs before we free it: */ |
6205 | barrier(); | |
6206 | ||
6207 | kfree(ret_stack); | |
f201ae23 | 6208 | } |
15e6cb36 | 6209 | #endif |