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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> | |
18 | #include <linux/kallsyms.h> | |
5072c59f | 19 | #include <linux/seq_file.h> |
4a2b8dda | 20 | #include <linux/suspend.h> |
8434dc93 | 21 | #include <linux/tracefs.h> |
3d083395 | 22 | #include <linux/hardirq.h> |
2d8b820b | 23 | #include <linux/kthread.h> |
5072c59f | 24 | #include <linux/uaccess.h> |
5855fead | 25 | #include <linux/bsearch.h> |
56d82e00 | 26 | #include <linux/module.h> |
2d8b820b | 27 | #include <linux/ftrace.h> |
b0fc494f | 28 | #include <linux/sysctl.h> |
5a0e3ad6 | 29 | #include <linux/slab.h> |
5072c59f | 30 | #include <linux/ctype.h> |
68950619 | 31 | #include <linux/sort.h> |
3d083395 | 32 | #include <linux/list.h> |
59df055f | 33 | #include <linux/hash.h> |
3f379b03 | 34 | #include <linux/rcupdate.h> |
3d083395 | 35 | |
ad8d75ff | 36 | #include <trace/events/sched.h> |
8aef2d28 | 37 | |
2af15d6a | 38 | #include <asm/setup.h> |
395a59d0 | 39 | |
0706f1c4 | 40 | #include "trace_output.h" |
bac429f0 | 41 | #include "trace_stat.h" |
16444a8a | 42 | |
6912896e | 43 | #define FTRACE_WARN_ON(cond) \ |
0778d9ad SR |
44 | ({ \ |
45 | int ___r = cond; \ | |
46 | if (WARN_ON(___r)) \ | |
6912896e | 47 | ftrace_kill(); \ |
0778d9ad SR |
48 | ___r; \ |
49 | }) | |
6912896e SR |
50 | |
51 | #define FTRACE_WARN_ON_ONCE(cond) \ | |
0778d9ad SR |
52 | ({ \ |
53 | int ___r = cond; \ | |
54 | if (WARN_ON_ONCE(___r)) \ | |
6912896e | 55 | ftrace_kill(); \ |
0778d9ad SR |
56 | ___r; \ |
57 | }) | |
6912896e | 58 | |
8fc0c701 SR |
59 | /* hash bits for specific function selection */ |
60 | #define FTRACE_HASH_BITS 7 | |
61 | #define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS) | |
33dc9b12 SR |
62 | #define FTRACE_HASH_DEFAULT_BITS 10 |
63 | #define FTRACE_HASH_MAX_BITS 12 | |
8fc0c701 | 64 | |
f04f24fb | 65 | #ifdef CONFIG_DYNAMIC_FTRACE |
33b7f99c SRRH |
66 | #define INIT_OPS_HASH(opsname) \ |
67 | .func_hash = &opsname.local_hash, \ | |
68 | .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock), | |
5f151b24 SRRH |
69 | #define ASSIGN_OPS_HASH(opsname, val) \ |
70 | .func_hash = val, \ | |
71 | .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock), | |
f04f24fb | 72 | #else |
33b7f99c | 73 | #define INIT_OPS_HASH(opsname) |
5f151b24 | 74 | #define ASSIGN_OPS_HASH(opsname, val) |
f04f24fb MH |
75 | #endif |
76 | ||
2f5f6ad9 SR |
77 | static struct ftrace_ops ftrace_list_end __read_mostly = { |
78 | .func = ftrace_stub, | |
395b97a3 | 79 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_STUB, |
33b7f99c | 80 | INIT_OPS_HASH(ftrace_list_end) |
2f5f6ad9 SR |
81 | }; |
82 | ||
4eebcc81 SR |
83 | /* ftrace_enabled is a method to turn ftrace on or off */ |
84 | int ftrace_enabled __read_mostly; | |
d61f82d0 | 85 | static int last_ftrace_enabled; |
b0fc494f | 86 | |
2f5f6ad9 SR |
87 | /* Current function tracing op */ |
88 | struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end; | |
405e1d83 SRRH |
89 | /* What to set function_trace_op to */ |
90 | static struct ftrace_ops *set_function_trace_op; | |
60a7ecf4 | 91 | |
345ddcc8 | 92 | static bool ftrace_pids_enabled(struct ftrace_ops *ops) |
e3eea140 | 93 | { |
345ddcc8 SRRH |
94 | struct trace_array *tr; |
95 | ||
96 | if (!(ops->flags & FTRACE_OPS_FL_PID) || !ops->private) | |
97 | return false; | |
98 | ||
99 | tr = ops->private; | |
100 | ||
101 | return tr->function_pids != NULL; | |
e3eea140 SRRH |
102 | } |
103 | ||
104 | static void ftrace_update_trampoline(struct ftrace_ops *ops); | |
105 | ||
4eebcc81 SR |
106 | /* |
107 | * ftrace_disabled is set when an anomaly is discovered. | |
108 | * ftrace_disabled is much stronger than ftrace_enabled. | |
109 | */ | |
110 | static int ftrace_disabled __read_mostly; | |
111 | ||
52baf119 | 112 | static DEFINE_MUTEX(ftrace_lock); |
b0fc494f | 113 | |
b848914c | 114 | static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end; |
16444a8a | 115 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; |
2b499381 | 116 | static struct ftrace_ops global_ops; |
16444a8a | 117 | |
2f5f6ad9 SR |
118 | #if ARCH_SUPPORTS_FTRACE_OPS |
119 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 120 | struct ftrace_ops *op, struct pt_regs *regs); |
2f5f6ad9 SR |
121 | #else |
122 | /* See comment below, where ftrace_ops_list_func is defined */ | |
123 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip); | |
124 | #define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops) | |
125 | #endif | |
b848914c | 126 | |
0a016409 SR |
127 | /* |
128 | * Traverse the ftrace_global_list, invoking all entries. The reason that we | |
1bb539ca | 129 | * can use rcu_dereference_raw_notrace() is that elements removed from this list |
0a016409 | 130 | * are simply leaked, so there is no need to interact with a grace-period |
1bb539ca | 131 | * mechanism. The rcu_dereference_raw_notrace() calls are needed to handle |
0a016409 SR |
132 | * concurrent insertions into the ftrace_global_list. |
133 | * | |
134 | * Silly Alpha and silly pointer-speculation compiler optimizations! | |
135 | */ | |
136 | #define do_for_each_ftrace_op(op, list) \ | |
1bb539ca | 137 | op = rcu_dereference_raw_notrace(list); \ |
0a016409 SR |
138 | do |
139 | ||
140 | /* | |
141 | * Optimized for just a single item in the list (as that is the normal case). | |
142 | */ | |
143 | #define while_for_each_ftrace_op(op) \ | |
1bb539ca | 144 | while (likely(op = rcu_dereference_raw_notrace((op)->next)) && \ |
0a016409 SR |
145 | unlikely((op) != &ftrace_list_end)) |
146 | ||
f04f24fb MH |
147 | static inline void ftrace_ops_init(struct ftrace_ops *ops) |
148 | { | |
149 | #ifdef CONFIG_DYNAMIC_FTRACE | |
150 | if (!(ops->flags & FTRACE_OPS_FL_INITIALIZED)) { | |
33b7f99c SRRH |
151 | mutex_init(&ops->local_hash.regex_lock); |
152 | ops->func_hash = &ops->local_hash; | |
f04f24fb MH |
153 | ops->flags |= FTRACE_OPS_FL_INITIALIZED; |
154 | } | |
155 | #endif | |
156 | } | |
157 | ||
ea701f11 SR |
158 | /** |
159 | * ftrace_nr_registered_ops - return number of ops registered | |
160 | * | |
161 | * Returns the number of ftrace_ops registered and tracing functions | |
162 | */ | |
163 | int ftrace_nr_registered_ops(void) | |
164 | { | |
165 | struct ftrace_ops *ops; | |
166 | int cnt = 0; | |
167 | ||
168 | mutex_lock(&ftrace_lock); | |
169 | ||
170 | for (ops = ftrace_ops_list; | |
171 | ops != &ftrace_list_end; ops = ops->next) | |
172 | cnt++; | |
173 | ||
174 | mutex_unlock(&ftrace_lock); | |
175 | ||
176 | return cnt; | |
177 | } | |
178 | ||
2f5f6ad9 | 179 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 180 | struct ftrace_ops *op, struct pt_regs *regs) |
df4fc315 | 181 | { |
345ddcc8 SRRH |
182 | struct trace_array *tr = op->private; |
183 | ||
184 | if (tr && this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid)) | |
df4fc315 SR |
185 | return; |
186 | ||
e3eea140 | 187 | op->saved_func(ip, parent_ip, op, regs); |
df4fc315 SR |
188 | } |
189 | ||
16444a8a | 190 | /** |
3d083395 | 191 | * clear_ftrace_function - reset the ftrace function |
16444a8a | 192 | * |
3d083395 SR |
193 | * This NULLs the ftrace function and in essence stops |
194 | * tracing. There may be lag | |
16444a8a | 195 | */ |
3d083395 | 196 | void clear_ftrace_function(void) |
16444a8a | 197 | { |
3d083395 SR |
198 | ftrace_trace_function = ftrace_stub; |
199 | } | |
200 | ||
ba27f2bc | 201 | static void per_cpu_ops_disable_all(struct ftrace_ops *ops) |
e248491a JO |
202 | { |
203 | int cpu; | |
204 | ||
205 | for_each_possible_cpu(cpu) | |
206 | *per_cpu_ptr(ops->disabled, cpu) = 1; | |
207 | } | |
208 | ||
ba27f2bc | 209 | static int per_cpu_ops_alloc(struct ftrace_ops *ops) |
e248491a JO |
210 | { |
211 | int __percpu *disabled; | |
212 | ||
ba27f2bc SRRH |
213 | if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_PER_CPU))) |
214 | return -EINVAL; | |
215 | ||
e248491a JO |
216 | disabled = alloc_percpu(int); |
217 | if (!disabled) | |
218 | return -ENOMEM; | |
219 | ||
220 | ops->disabled = disabled; | |
ba27f2bc | 221 | per_cpu_ops_disable_all(ops); |
e248491a JO |
222 | return 0; |
223 | } | |
224 | ||
405e1d83 SRRH |
225 | static void ftrace_sync(struct work_struct *work) |
226 | { | |
227 | /* | |
228 | * This function is just a stub to implement a hard force | |
229 | * of synchronize_sched(). This requires synchronizing | |
230 | * tasks even in userspace and idle. | |
231 | * | |
232 | * Yes, function tracing is rude. | |
233 | */ | |
234 | } | |
235 | ||
236 | static void ftrace_sync_ipi(void *data) | |
237 | { | |
238 | /* Probably not needed, but do it anyway */ | |
239 | smp_rmb(); | |
240 | } | |
241 | ||
23a8e844 SRRH |
242 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
243 | static void update_function_graph_func(void); | |
55577204 SRRH |
244 | |
245 | /* Both enabled by default (can be cleared by function_graph tracer flags */ | |
246 | static bool fgraph_sleep_time = true; | |
247 | static bool fgraph_graph_time = true; | |
248 | ||
23a8e844 SRRH |
249 | #else |
250 | static inline void update_function_graph_func(void) { } | |
251 | #endif | |
252 | ||
00ccbf2f SRRH |
253 | |
254 | static ftrace_func_t ftrace_ops_get_list_func(struct ftrace_ops *ops) | |
255 | { | |
256 | /* | |
ba27f2bc | 257 | * If this is a dynamic, RCU, or per CPU ops, or we force list func, |
00ccbf2f SRRH |
258 | * then it needs to call the list anyway. |
259 | */ | |
ba27f2bc SRRH |
260 | if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_PER_CPU | |
261 | FTRACE_OPS_FL_RCU) || FTRACE_FORCE_LIST_FUNC) | |
00ccbf2f SRRH |
262 | return ftrace_ops_list_func; |
263 | ||
264 | return ftrace_ops_get_func(ops); | |
265 | } | |
266 | ||
2b499381 SR |
267 | static void update_ftrace_function(void) |
268 | { | |
269 | ftrace_func_t func; | |
270 | ||
f7aad4e1 SRRH |
271 | /* |
272 | * Prepare the ftrace_ops that the arch callback will use. | |
273 | * If there's only one ftrace_ops registered, the ftrace_ops_list | |
274 | * will point to the ops we want. | |
275 | */ | |
276 | set_function_trace_op = ftrace_ops_list; | |
277 | ||
278 | /* If there's no ftrace_ops registered, just call the stub function */ | |
279 | if (ftrace_ops_list == &ftrace_list_end) { | |
280 | func = ftrace_stub; | |
281 | ||
cdbe61bf SR |
282 | /* |
283 | * If we are at the end of the list and this ops is | |
4740974a SR |
284 | * recursion safe and not dynamic and the arch supports passing ops, |
285 | * then have the mcount trampoline call the function directly. | |
cdbe61bf | 286 | */ |
f7aad4e1 | 287 | } else if (ftrace_ops_list->next == &ftrace_list_end) { |
00ccbf2f | 288 | func = ftrace_ops_get_list_func(ftrace_ops_list); |
f7aad4e1 | 289 | |
2f5f6ad9 SR |
290 | } else { |
291 | /* Just use the default ftrace_ops */ | |
405e1d83 | 292 | set_function_trace_op = &ftrace_list_end; |
b848914c | 293 | func = ftrace_ops_list_func; |
2f5f6ad9 | 294 | } |
2b499381 | 295 | |
5f8bf2d2 SRRH |
296 | update_function_graph_func(); |
297 | ||
405e1d83 SRRH |
298 | /* If there's no change, then do nothing more here */ |
299 | if (ftrace_trace_function == func) | |
300 | return; | |
301 | ||
302 | /* | |
303 | * If we are using the list function, it doesn't care | |
304 | * about the function_trace_ops. | |
305 | */ | |
306 | if (func == ftrace_ops_list_func) { | |
307 | ftrace_trace_function = func; | |
308 | /* | |
309 | * Don't even bother setting function_trace_ops, | |
310 | * it would be racy to do so anyway. | |
311 | */ | |
312 | return; | |
313 | } | |
314 | ||
315 | #ifndef CONFIG_DYNAMIC_FTRACE | |
316 | /* | |
317 | * For static tracing, we need to be a bit more careful. | |
318 | * The function change takes affect immediately. Thus, | |
319 | * we need to coorditate the setting of the function_trace_ops | |
320 | * with the setting of the ftrace_trace_function. | |
321 | * | |
322 | * Set the function to the list ops, which will call the | |
323 | * function we want, albeit indirectly, but it handles the | |
324 | * ftrace_ops and doesn't depend on function_trace_op. | |
325 | */ | |
326 | ftrace_trace_function = ftrace_ops_list_func; | |
327 | /* | |
328 | * Make sure all CPUs see this. Yes this is slow, but static | |
329 | * tracing is slow and nasty to have enabled. | |
330 | */ | |
331 | schedule_on_each_cpu(ftrace_sync); | |
332 | /* Now all cpus are using the list ops. */ | |
333 | function_trace_op = set_function_trace_op; | |
334 | /* Make sure the function_trace_op is visible on all CPUs */ | |
335 | smp_wmb(); | |
336 | /* Nasty way to force a rmb on all cpus */ | |
337 | smp_call_function(ftrace_sync_ipi, NULL, 1); | |
338 | /* OK, we are all set to update the ftrace_trace_function now! */ | |
339 | #endif /* !CONFIG_DYNAMIC_FTRACE */ | |
340 | ||
491d0dcf | 341 | ftrace_trace_function = func; |
491d0dcf SR |
342 | } |
343 | ||
7eea4fce JW |
344 | int using_ftrace_ops_list_func(void) |
345 | { | |
346 | return ftrace_trace_function == ftrace_ops_list_func; | |
347 | } | |
348 | ||
2b499381 | 349 | static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
3d083395 | 350 | { |
2b499381 | 351 | ops->next = *list; |
16444a8a | 352 | /* |
b848914c | 353 | * We are entering ops into the list but another |
16444a8a ACM |
354 | * CPU might be walking that list. We need to make sure |
355 | * the ops->next pointer is valid before another CPU sees | |
b848914c | 356 | * the ops pointer included into the list. |
16444a8a | 357 | */ |
2b499381 | 358 | rcu_assign_pointer(*list, ops); |
16444a8a ACM |
359 | } |
360 | ||
2b499381 | 361 | static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
16444a8a | 362 | { |
16444a8a | 363 | struct ftrace_ops **p; |
16444a8a ACM |
364 | |
365 | /* | |
3d083395 SR |
366 | * If we are removing the last function, then simply point |
367 | * to the ftrace_stub. | |
16444a8a | 368 | */ |
2b499381 SR |
369 | if (*list == ops && ops->next == &ftrace_list_end) { |
370 | *list = &ftrace_list_end; | |
e6ea44e9 | 371 | return 0; |
16444a8a ACM |
372 | } |
373 | ||
2b499381 | 374 | for (p = list; *p != &ftrace_list_end; p = &(*p)->next) |
16444a8a ACM |
375 | if (*p == ops) |
376 | break; | |
377 | ||
e6ea44e9 SR |
378 | if (*p != ops) |
379 | return -1; | |
16444a8a ACM |
380 | |
381 | *p = (*p)->next; | |
2b499381 SR |
382 | return 0; |
383 | } | |
16444a8a | 384 | |
f3bea491 SRRH |
385 | static void ftrace_update_trampoline(struct ftrace_ops *ops); |
386 | ||
2b499381 SR |
387 | static int __register_ftrace_function(struct ftrace_ops *ops) |
388 | { | |
591dffda SRRH |
389 | if (ops->flags & FTRACE_OPS_FL_DELETED) |
390 | return -EINVAL; | |
391 | ||
b848914c SR |
392 | if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED)) |
393 | return -EBUSY; | |
394 | ||
06aeaaea | 395 | #ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
08f6fba5 SR |
396 | /* |
397 | * If the ftrace_ops specifies SAVE_REGS, then it only can be used | |
398 | * if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set. | |
399 | * Setting SAVE_REGS_IF_SUPPORTED makes SAVE_REGS irrelevant. | |
400 | */ | |
401 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS && | |
402 | !(ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)) | |
403 | return -EINVAL; | |
404 | ||
405 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED) | |
406 | ops->flags |= FTRACE_OPS_FL_SAVE_REGS; | |
407 | #endif | |
408 | ||
cdbe61bf SR |
409 | if (!core_kernel_data((unsigned long)ops)) |
410 | ops->flags |= FTRACE_OPS_FL_DYNAMIC; | |
411 | ||
ba27f2bc SRRH |
412 | if (ops->flags & FTRACE_OPS_FL_PER_CPU) { |
413 | if (per_cpu_ops_alloc(ops)) | |
e248491a | 414 | return -ENOMEM; |
ba27f2bc SRRH |
415 | } |
416 | ||
417 | add_ftrace_ops(&ftrace_ops_list, ops); | |
b848914c | 418 | |
e3eea140 SRRH |
419 | /* Always save the function, and reset at unregistering */ |
420 | ops->saved_func = ops->func; | |
421 | ||
345ddcc8 | 422 | if (ftrace_pids_enabled(ops)) |
e3eea140 SRRH |
423 | ops->func = ftrace_pid_func; |
424 | ||
f3bea491 SRRH |
425 | ftrace_update_trampoline(ops); |
426 | ||
2b499381 SR |
427 | if (ftrace_enabled) |
428 | update_ftrace_function(); | |
429 | ||
430 | return 0; | |
431 | } | |
432 | ||
433 | static int __unregister_ftrace_function(struct ftrace_ops *ops) | |
434 | { | |
435 | int ret; | |
436 | ||
b848914c SR |
437 | if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) |
438 | return -EBUSY; | |
439 | ||
ba27f2bc | 440 | ret = remove_ftrace_ops(&ftrace_ops_list, ops); |
b848914c | 441 | |
2b499381 SR |
442 | if (ret < 0) |
443 | return ret; | |
b848914c | 444 | |
491d0dcf SR |
445 | if (ftrace_enabled) |
446 | update_ftrace_function(); | |
16444a8a | 447 | |
e3eea140 SRRH |
448 | ops->func = ops->saved_func; |
449 | ||
e6ea44e9 | 450 | return 0; |
3d083395 SR |
451 | } |
452 | ||
df4fc315 SR |
453 | static void ftrace_update_pid_func(void) |
454 | { | |
e3eea140 SRRH |
455 | struct ftrace_ops *op; |
456 | ||
491d0dcf | 457 | /* Only do something if we are tracing something */ |
df4fc315 | 458 | if (ftrace_trace_function == ftrace_stub) |
10dd3ebe | 459 | return; |
df4fc315 | 460 | |
e3eea140 SRRH |
461 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
462 | if (op->flags & FTRACE_OPS_FL_PID) { | |
345ddcc8 SRRH |
463 | op->func = ftrace_pids_enabled(op) ? |
464 | ftrace_pid_func : op->saved_func; | |
e3eea140 SRRH |
465 | ftrace_update_trampoline(op); |
466 | } | |
467 | } while_for_each_ftrace_op(op); | |
468 | ||
491d0dcf | 469 | update_ftrace_function(); |
df4fc315 SR |
470 | } |
471 | ||
493762fc SR |
472 | #ifdef CONFIG_FUNCTION_PROFILER |
473 | struct ftrace_profile { | |
474 | struct hlist_node node; | |
475 | unsigned long ip; | |
476 | unsigned long counter; | |
0706f1c4 SR |
477 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
478 | unsigned long long time; | |
e330b3bc | 479 | unsigned long long time_squared; |
0706f1c4 | 480 | #endif |
8fc0c701 SR |
481 | }; |
482 | ||
493762fc SR |
483 | struct ftrace_profile_page { |
484 | struct ftrace_profile_page *next; | |
485 | unsigned long index; | |
486 | struct ftrace_profile records[]; | |
d61f82d0 SR |
487 | }; |
488 | ||
cafb168a SR |
489 | struct ftrace_profile_stat { |
490 | atomic_t disabled; | |
491 | struct hlist_head *hash; | |
492 | struct ftrace_profile_page *pages; | |
493 | struct ftrace_profile_page *start; | |
494 | struct tracer_stat stat; | |
495 | }; | |
496 | ||
493762fc SR |
497 | #define PROFILE_RECORDS_SIZE \ |
498 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | |
5072c59f | 499 | |
493762fc SR |
500 | #define PROFILES_PER_PAGE \ |
501 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | |
3d083395 | 502 | |
fb9fb015 SR |
503 | static int ftrace_profile_enabled __read_mostly; |
504 | ||
505 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ | |
bac429f0 SR |
506 | static DEFINE_MUTEX(ftrace_profile_lock); |
507 | ||
cafb168a | 508 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); |
493762fc | 509 | |
20079ebe NK |
510 | #define FTRACE_PROFILE_HASH_BITS 10 |
511 | #define FTRACE_PROFILE_HASH_SIZE (1 << FTRACE_PROFILE_HASH_BITS) | |
493762fc | 512 | |
bac429f0 SR |
513 | static void * |
514 | function_stat_next(void *v, int idx) | |
515 | { | |
493762fc SR |
516 | struct ftrace_profile *rec = v; |
517 | struct ftrace_profile_page *pg; | |
bac429f0 | 518 | |
493762fc | 519 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
bac429f0 SR |
520 | |
521 | again: | |
0296e425 LZ |
522 | if (idx != 0) |
523 | rec++; | |
524 | ||
bac429f0 SR |
525 | if ((void *)rec >= (void *)&pg->records[pg->index]) { |
526 | pg = pg->next; | |
527 | if (!pg) | |
528 | return NULL; | |
529 | rec = &pg->records[0]; | |
493762fc SR |
530 | if (!rec->counter) |
531 | goto again; | |
bac429f0 SR |
532 | } |
533 | ||
bac429f0 SR |
534 | return rec; |
535 | } | |
536 | ||
537 | static void *function_stat_start(struct tracer_stat *trace) | |
538 | { | |
cafb168a SR |
539 | struct ftrace_profile_stat *stat = |
540 | container_of(trace, struct ftrace_profile_stat, stat); | |
541 | ||
542 | if (!stat || !stat->start) | |
543 | return NULL; | |
544 | ||
545 | return function_stat_next(&stat->start->records[0], 0); | |
bac429f0 SR |
546 | } |
547 | ||
0706f1c4 SR |
548 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
549 | /* function graph compares on total time */ | |
550 | static int function_stat_cmp(void *p1, void *p2) | |
551 | { | |
552 | struct ftrace_profile *a = p1; | |
553 | struct ftrace_profile *b = p2; | |
554 | ||
555 | if (a->time < b->time) | |
556 | return -1; | |
557 | if (a->time > b->time) | |
558 | return 1; | |
559 | else | |
560 | return 0; | |
561 | } | |
562 | #else | |
563 | /* not function graph compares against hits */ | |
bac429f0 SR |
564 | static int function_stat_cmp(void *p1, void *p2) |
565 | { | |
493762fc SR |
566 | struct ftrace_profile *a = p1; |
567 | struct ftrace_profile *b = p2; | |
bac429f0 SR |
568 | |
569 | if (a->counter < b->counter) | |
570 | return -1; | |
571 | if (a->counter > b->counter) | |
572 | return 1; | |
573 | else | |
574 | return 0; | |
575 | } | |
0706f1c4 | 576 | #endif |
bac429f0 SR |
577 | |
578 | static int function_stat_headers(struct seq_file *m) | |
579 | { | |
0706f1c4 | 580 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
fa6f0cc7 RV |
581 | seq_puts(m, " Function " |
582 | "Hit Time Avg s^2\n" | |
583 | " -------- " | |
584 | "--- ---- --- ---\n"); | |
0706f1c4 | 585 | #else |
fa6f0cc7 RV |
586 | seq_puts(m, " Function Hit\n" |
587 | " -------- ---\n"); | |
0706f1c4 | 588 | #endif |
bac429f0 SR |
589 | return 0; |
590 | } | |
591 | ||
592 | static int function_stat_show(struct seq_file *m, void *v) | |
593 | { | |
493762fc | 594 | struct ftrace_profile *rec = v; |
bac429f0 | 595 | char str[KSYM_SYMBOL_LEN]; |
3aaba20f | 596 | int ret = 0; |
0706f1c4 | 597 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b SR |
598 | static struct trace_seq s; |
599 | unsigned long long avg; | |
e330b3bc | 600 | unsigned long long stddev; |
0706f1c4 | 601 | #endif |
3aaba20f LZ |
602 | mutex_lock(&ftrace_profile_lock); |
603 | ||
604 | /* we raced with function_profile_reset() */ | |
605 | if (unlikely(rec->counter == 0)) { | |
606 | ret = -EBUSY; | |
607 | goto out; | |
608 | } | |
bac429f0 | 609 | |
8e436ca0 UT |
610 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
611 | avg = rec->time; | |
612 | do_div(avg, rec->counter); | |
613 | if (tracing_thresh && (avg < tracing_thresh)) | |
614 | goto out; | |
615 | #endif | |
616 | ||
bac429f0 | 617 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); |
0706f1c4 SR |
618 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); |
619 | ||
620 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
fa6f0cc7 | 621 | seq_puts(m, " "); |
34886c8b | 622 | |
e330b3bc CD |
623 | /* Sample standard deviation (s^2) */ |
624 | if (rec->counter <= 1) | |
625 | stddev = 0; | |
626 | else { | |
52d85d76 JL |
627 | /* |
628 | * Apply Welford's method: | |
629 | * s^2 = 1 / (n * (n-1)) * (n * \Sum (x_i)^2 - (\Sum x_i)^2) | |
630 | */ | |
631 | stddev = rec->counter * rec->time_squared - | |
632 | rec->time * rec->time; | |
633 | ||
e330b3bc CD |
634 | /* |
635 | * Divide only 1000 for ns^2 -> us^2 conversion. | |
636 | * trace_print_graph_duration will divide 1000 again. | |
637 | */ | |
52d85d76 | 638 | do_div(stddev, rec->counter * (rec->counter - 1) * 1000); |
e330b3bc CD |
639 | } |
640 | ||
34886c8b SR |
641 | trace_seq_init(&s); |
642 | trace_print_graph_duration(rec->time, &s); | |
643 | trace_seq_puts(&s, " "); | |
644 | trace_print_graph_duration(avg, &s); | |
e330b3bc CD |
645 | trace_seq_puts(&s, " "); |
646 | trace_print_graph_duration(stddev, &s); | |
0706f1c4 | 647 | trace_print_seq(m, &s); |
0706f1c4 SR |
648 | #endif |
649 | seq_putc(m, '\n'); | |
3aaba20f LZ |
650 | out: |
651 | mutex_unlock(&ftrace_profile_lock); | |
bac429f0 | 652 | |
3aaba20f | 653 | return ret; |
bac429f0 SR |
654 | } |
655 | ||
cafb168a | 656 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) |
bac429f0 | 657 | { |
493762fc | 658 | struct ftrace_profile_page *pg; |
bac429f0 | 659 | |
cafb168a | 660 | pg = stat->pages = stat->start; |
bac429f0 | 661 | |
493762fc SR |
662 | while (pg) { |
663 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | |
664 | pg->index = 0; | |
665 | pg = pg->next; | |
bac429f0 SR |
666 | } |
667 | ||
cafb168a | 668 | memset(stat->hash, 0, |
493762fc SR |
669 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); |
670 | } | |
bac429f0 | 671 | |
cafb168a | 672 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) |
493762fc SR |
673 | { |
674 | struct ftrace_profile_page *pg; | |
318e0a73 SR |
675 | int functions; |
676 | int pages; | |
493762fc | 677 | int i; |
bac429f0 | 678 | |
493762fc | 679 | /* If we already allocated, do nothing */ |
cafb168a | 680 | if (stat->pages) |
493762fc | 681 | return 0; |
bac429f0 | 682 | |
cafb168a SR |
683 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); |
684 | if (!stat->pages) | |
493762fc | 685 | return -ENOMEM; |
bac429f0 | 686 | |
318e0a73 SR |
687 | #ifdef CONFIG_DYNAMIC_FTRACE |
688 | functions = ftrace_update_tot_cnt; | |
689 | #else | |
690 | /* | |
691 | * We do not know the number of functions that exist because | |
692 | * dynamic tracing is what counts them. With past experience | |
693 | * we have around 20K functions. That should be more than enough. | |
694 | * It is highly unlikely we will execute every function in | |
695 | * the kernel. | |
696 | */ | |
697 | functions = 20000; | |
698 | #endif | |
699 | ||
cafb168a | 700 | pg = stat->start = stat->pages; |
bac429f0 | 701 | |
318e0a73 SR |
702 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); |
703 | ||
39e30cd1 | 704 | for (i = 1; i < pages; i++) { |
493762fc | 705 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
493762fc | 706 | if (!pg->next) |
318e0a73 | 707 | goto out_free; |
493762fc SR |
708 | pg = pg->next; |
709 | } | |
710 | ||
711 | return 0; | |
318e0a73 SR |
712 | |
713 | out_free: | |
714 | pg = stat->start; | |
715 | while (pg) { | |
716 | unsigned long tmp = (unsigned long)pg; | |
717 | ||
718 | pg = pg->next; | |
719 | free_page(tmp); | |
720 | } | |
721 | ||
318e0a73 SR |
722 | stat->pages = NULL; |
723 | stat->start = NULL; | |
724 | ||
725 | return -ENOMEM; | |
bac429f0 SR |
726 | } |
727 | ||
cafb168a | 728 | static int ftrace_profile_init_cpu(int cpu) |
bac429f0 | 729 | { |
cafb168a | 730 | struct ftrace_profile_stat *stat; |
493762fc | 731 | int size; |
bac429f0 | 732 | |
cafb168a SR |
733 | stat = &per_cpu(ftrace_profile_stats, cpu); |
734 | ||
735 | if (stat->hash) { | |
493762fc | 736 | /* If the profile is already created, simply reset it */ |
cafb168a | 737 | ftrace_profile_reset(stat); |
493762fc SR |
738 | return 0; |
739 | } | |
bac429f0 | 740 | |
493762fc SR |
741 | /* |
742 | * We are profiling all functions, but usually only a few thousand | |
743 | * functions are hit. We'll make a hash of 1024 items. | |
744 | */ | |
745 | size = FTRACE_PROFILE_HASH_SIZE; | |
bac429f0 | 746 | |
cafb168a | 747 | stat->hash = kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL); |
493762fc | 748 | |
cafb168a | 749 | if (!stat->hash) |
493762fc SR |
750 | return -ENOMEM; |
751 | ||
318e0a73 | 752 | /* Preallocate the function profiling pages */ |
cafb168a SR |
753 | if (ftrace_profile_pages_init(stat) < 0) { |
754 | kfree(stat->hash); | |
755 | stat->hash = NULL; | |
493762fc SR |
756 | return -ENOMEM; |
757 | } | |
758 | ||
759 | return 0; | |
bac429f0 SR |
760 | } |
761 | ||
cafb168a SR |
762 | static int ftrace_profile_init(void) |
763 | { | |
764 | int cpu; | |
765 | int ret = 0; | |
766 | ||
c4602c1c | 767 | for_each_possible_cpu(cpu) { |
cafb168a SR |
768 | ret = ftrace_profile_init_cpu(cpu); |
769 | if (ret) | |
770 | break; | |
771 | } | |
772 | ||
773 | return ret; | |
774 | } | |
775 | ||
493762fc | 776 | /* interrupts must be disabled */ |
cafb168a SR |
777 | static struct ftrace_profile * |
778 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) | |
bac429f0 | 779 | { |
493762fc | 780 | struct ftrace_profile *rec; |
bac429f0 | 781 | struct hlist_head *hhd; |
bac429f0 SR |
782 | unsigned long key; |
783 | ||
20079ebe | 784 | key = hash_long(ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 785 | hhd = &stat->hash[key]; |
bac429f0 SR |
786 | |
787 | if (hlist_empty(hhd)) | |
788 | return NULL; | |
789 | ||
1bb539ca | 790 | hlist_for_each_entry_rcu_notrace(rec, hhd, node) { |
bac429f0 | 791 | if (rec->ip == ip) |
493762fc SR |
792 | return rec; |
793 | } | |
794 | ||
795 | return NULL; | |
796 | } | |
797 | ||
cafb168a SR |
798 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, |
799 | struct ftrace_profile *rec) | |
493762fc SR |
800 | { |
801 | unsigned long key; | |
802 | ||
20079ebe | 803 | key = hash_long(rec->ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 804 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); |
493762fc SR |
805 | } |
806 | ||
318e0a73 SR |
807 | /* |
808 | * The memory is already allocated, this simply finds a new record to use. | |
809 | */ | |
493762fc | 810 | static struct ftrace_profile * |
318e0a73 | 811 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) |
493762fc SR |
812 | { |
813 | struct ftrace_profile *rec = NULL; | |
814 | ||
318e0a73 | 815 | /* prevent recursion (from NMIs) */ |
cafb168a | 816 | if (atomic_inc_return(&stat->disabled) != 1) |
493762fc SR |
817 | goto out; |
818 | ||
493762fc | 819 | /* |
318e0a73 SR |
820 | * Try to find the function again since an NMI |
821 | * could have added it | |
493762fc | 822 | */ |
cafb168a | 823 | rec = ftrace_find_profiled_func(stat, ip); |
493762fc | 824 | if (rec) |
cafb168a | 825 | goto out; |
493762fc | 826 | |
cafb168a SR |
827 | if (stat->pages->index == PROFILES_PER_PAGE) { |
828 | if (!stat->pages->next) | |
829 | goto out; | |
830 | stat->pages = stat->pages->next; | |
bac429f0 | 831 | } |
493762fc | 832 | |
cafb168a | 833 | rec = &stat->pages->records[stat->pages->index++]; |
493762fc | 834 | rec->ip = ip; |
cafb168a | 835 | ftrace_add_profile(stat, rec); |
493762fc | 836 | |
bac429f0 | 837 | out: |
cafb168a | 838 | atomic_dec(&stat->disabled); |
bac429f0 SR |
839 | |
840 | return rec; | |
841 | } | |
842 | ||
843 | static void | |
2f5f6ad9 | 844 | function_profile_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 845 | struct ftrace_ops *ops, struct pt_regs *regs) |
bac429f0 | 846 | { |
cafb168a | 847 | struct ftrace_profile_stat *stat; |
493762fc | 848 | struct ftrace_profile *rec; |
bac429f0 SR |
849 | unsigned long flags; |
850 | ||
851 | if (!ftrace_profile_enabled) | |
852 | return; | |
853 | ||
854 | local_irq_save(flags); | |
cafb168a | 855 | |
bdffd893 | 856 | stat = this_cpu_ptr(&ftrace_profile_stats); |
0f6ce3de | 857 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
858 | goto out; |
859 | ||
860 | rec = ftrace_find_profiled_func(stat, ip); | |
493762fc | 861 | if (!rec) { |
318e0a73 | 862 | rec = ftrace_profile_alloc(stat, ip); |
493762fc SR |
863 | if (!rec) |
864 | goto out; | |
865 | } | |
bac429f0 SR |
866 | |
867 | rec->counter++; | |
868 | out: | |
869 | local_irq_restore(flags); | |
870 | } | |
871 | ||
0706f1c4 SR |
872 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
873 | static int profile_graph_entry(struct ftrace_graph_ent *trace) | |
874 | { | |
a1e2e31d | 875 | function_profile_call(trace->func, 0, NULL, NULL); |
0706f1c4 SR |
876 | return 1; |
877 | } | |
878 | ||
879 | static void profile_graph_return(struct ftrace_graph_ret *trace) | |
880 | { | |
cafb168a | 881 | struct ftrace_profile_stat *stat; |
a2a16d6a | 882 | unsigned long long calltime; |
0706f1c4 | 883 | struct ftrace_profile *rec; |
cafb168a | 884 | unsigned long flags; |
0706f1c4 SR |
885 | |
886 | local_irq_save(flags); | |
bdffd893 | 887 | stat = this_cpu_ptr(&ftrace_profile_stats); |
0f6ce3de | 888 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
889 | goto out; |
890 | ||
37e44bc5 SR |
891 | /* If the calltime was zero'd ignore it */ |
892 | if (!trace->calltime) | |
893 | goto out; | |
894 | ||
a2a16d6a SR |
895 | calltime = trace->rettime - trace->calltime; |
896 | ||
55577204 | 897 | if (!fgraph_graph_time) { |
a2a16d6a SR |
898 | int index; |
899 | ||
900 | index = trace->depth; | |
901 | ||
902 | /* Append this call time to the parent time to subtract */ | |
903 | if (index) | |
904 | current->ret_stack[index - 1].subtime += calltime; | |
905 | ||
906 | if (current->ret_stack[index].subtime < calltime) | |
907 | calltime -= current->ret_stack[index].subtime; | |
908 | else | |
909 | calltime = 0; | |
910 | } | |
911 | ||
cafb168a | 912 | rec = ftrace_find_profiled_func(stat, trace->func); |
e330b3bc | 913 | if (rec) { |
a2a16d6a | 914 | rec->time += calltime; |
e330b3bc CD |
915 | rec->time_squared += calltime * calltime; |
916 | } | |
a2a16d6a | 917 | |
cafb168a | 918 | out: |
0706f1c4 SR |
919 | local_irq_restore(flags); |
920 | } | |
921 | ||
922 | static int register_ftrace_profiler(void) | |
923 | { | |
924 | return register_ftrace_graph(&profile_graph_return, | |
925 | &profile_graph_entry); | |
926 | } | |
927 | ||
928 | static void unregister_ftrace_profiler(void) | |
929 | { | |
930 | unregister_ftrace_graph(); | |
931 | } | |
932 | #else | |
bd38c0e6 | 933 | static struct ftrace_ops ftrace_profile_ops __read_mostly = { |
fb9fb015 | 934 | .func = function_profile_call, |
f04f24fb | 935 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, |
33b7f99c | 936 | INIT_OPS_HASH(ftrace_profile_ops) |
bac429f0 SR |
937 | }; |
938 | ||
0706f1c4 SR |
939 | static int register_ftrace_profiler(void) |
940 | { | |
941 | return register_ftrace_function(&ftrace_profile_ops); | |
942 | } | |
943 | ||
944 | static void unregister_ftrace_profiler(void) | |
945 | { | |
946 | unregister_ftrace_function(&ftrace_profile_ops); | |
947 | } | |
948 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
949 | ||
bac429f0 SR |
950 | static ssize_t |
951 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | |
952 | size_t cnt, loff_t *ppos) | |
953 | { | |
954 | unsigned long val; | |
bac429f0 SR |
955 | int ret; |
956 | ||
22fe9b54 PH |
957 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
958 | if (ret) | |
bac429f0 SR |
959 | return ret; |
960 | ||
961 | val = !!val; | |
962 | ||
963 | mutex_lock(&ftrace_profile_lock); | |
964 | if (ftrace_profile_enabled ^ val) { | |
965 | if (val) { | |
493762fc SR |
966 | ret = ftrace_profile_init(); |
967 | if (ret < 0) { | |
968 | cnt = ret; | |
969 | goto out; | |
970 | } | |
971 | ||
0706f1c4 SR |
972 | ret = register_ftrace_profiler(); |
973 | if (ret < 0) { | |
974 | cnt = ret; | |
975 | goto out; | |
976 | } | |
bac429f0 SR |
977 | ftrace_profile_enabled = 1; |
978 | } else { | |
979 | ftrace_profile_enabled = 0; | |
0f6ce3de SR |
980 | /* |
981 | * unregister_ftrace_profiler calls stop_machine | |
982 | * so this acts like an synchronize_sched. | |
983 | */ | |
0706f1c4 | 984 | unregister_ftrace_profiler(); |
bac429f0 SR |
985 | } |
986 | } | |
493762fc | 987 | out: |
bac429f0 SR |
988 | mutex_unlock(&ftrace_profile_lock); |
989 | ||
cf8517cf | 990 | *ppos += cnt; |
bac429f0 SR |
991 | |
992 | return cnt; | |
993 | } | |
994 | ||
493762fc SR |
995 | static ssize_t |
996 | ftrace_profile_read(struct file *filp, char __user *ubuf, | |
997 | size_t cnt, loff_t *ppos) | |
998 | { | |
fb9fb015 | 999 | char buf[64]; /* big enough to hold a number */ |
493762fc SR |
1000 | int r; |
1001 | ||
1002 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | |
1003 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
1004 | } | |
1005 | ||
bac429f0 SR |
1006 | static const struct file_operations ftrace_profile_fops = { |
1007 | .open = tracing_open_generic, | |
1008 | .read = ftrace_profile_read, | |
1009 | .write = ftrace_profile_write, | |
6038f373 | 1010 | .llseek = default_llseek, |
bac429f0 SR |
1011 | }; |
1012 | ||
cafb168a SR |
1013 | /* used to initialize the real stat files */ |
1014 | static struct tracer_stat function_stats __initdata = { | |
fb9fb015 SR |
1015 | .name = "functions", |
1016 | .stat_start = function_stat_start, | |
1017 | .stat_next = function_stat_next, | |
1018 | .stat_cmp = function_stat_cmp, | |
1019 | .stat_headers = function_stat_headers, | |
1020 | .stat_show = function_stat_show | |
cafb168a SR |
1021 | }; |
1022 | ||
8434dc93 | 1023 | static __init void ftrace_profile_tracefs(struct dentry *d_tracer) |
bac429f0 | 1024 | { |
cafb168a | 1025 | struct ftrace_profile_stat *stat; |
bac429f0 | 1026 | struct dentry *entry; |
cafb168a | 1027 | char *name; |
bac429f0 | 1028 | int ret; |
cafb168a SR |
1029 | int cpu; |
1030 | ||
1031 | for_each_possible_cpu(cpu) { | |
1032 | stat = &per_cpu(ftrace_profile_stats, cpu); | |
1033 | ||
6363c6b5 | 1034 | name = kasprintf(GFP_KERNEL, "function%d", cpu); |
cafb168a SR |
1035 | if (!name) { |
1036 | /* | |
1037 | * The files created are permanent, if something happens | |
1038 | * we still do not free memory. | |
1039 | */ | |
cafb168a SR |
1040 | WARN(1, |
1041 | "Could not allocate stat file for cpu %d\n", | |
1042 | cpu); | |
1043 | return; | |
1044 | } | |
1045 | stat->stat = function_stats; | |
cafb168a SR |
1046 | stat->stat.name = name; |
1047 | ret = register_stat_tracer(&stat->stat); | |
1048 | if (ret) { | |
1049 | WARN(1, | |
1050 | "Could not register function stat for cpu %d\n", | |
1051 | cpu); | |
1052 | kfree(name); | |
1053 | return; | |
1054 | } | |
bac429f0 SR |
1055 | } |
1056 | ||
8434dc93 | 1057 | entry = tracefs_create_file("function_profile_enabled", 0644, |
bac429f0 SR |
1058 | d_tracer, NULL, &ftrace_profile_fops); |
1059 | if (!entry) | |
a395d6a7 | 1060 | pr_warn("Could not create tracefs 'function_profile_enabled' entry\n"); |
bac429f0 SR |
1061 | } |
1062 | ||
bac429f0 | 1063 | #else /* CONFIG_FUNCTION_PROFILER */ |
8434dc93 | 1064 | static __init void ftrace_profile_tracefs(struct dentry *d_tracer) |
bac429f0 SR |
1065 | { |
1066 | } | |
bac429f0 SR |
1067 | #endif /* CONFIG_FUNCTION_PROFILER */ |
1068 | ||
493762fc SR |
1069 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; |
1070 | ||
1619dc3f PA |
1071 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
1072 | static int ftrace_graph_active; | |
1073 | #else | |
1074 | # define ftrace_graph_active 0 | |
1075 | #endif | |
1076 | ||
493762fc SR |
1077 | #ifdef CONFIG_DYNAMIC_FTRACE |
1078 | ||
79922b80 SRRH |
1079 | static struct ftrace_ops *removed_ops; |
1080 | ||
e1effa01 SRRH |
1081 | /* |
1082 | * Set when doing a global update, like enabling all recs or disabling them. | |
1083 | * It is not set when just updating a single ftrace_ops. | |
1084 | */ | |
1085 | static bool update_all_ops; | |
1086 | ||
493762fc SR |
1087 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD |
1088 | # error Dynamic ftrace depends on MCOUNT_RECORD | |
1089 | #endif | |
1090 | ||
1091 | static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly; | |
1092 | ||
1093 | struct ftrace_func_probe { | |
1094 | struct hlist_node node; | |
1095 | struct ftrace_probe_ops *ops; | |
1096 | unsigned long flags; | |
1097 | unsigned long ip; | |
1098 | void *data; | |
7818b388 | 1099 | struct list_head free_list; |
493762fc SR |
1100 | }; |
1101 | ||
b448c4e3 SR |
1102 | struct ftrace_func_entry { |
1103 | struct hlist_node hlist; | |
1104 | unsigned long ip; | |
1105 | }; | |
1106 | ||
1107 | struct ftrace_hash { | |
1108 | unsigned long size_bits; | |
1109 | struct hlist_head *buckets; | |
1110 | unsigned long count; | |
07fd5515 | 1111 | struct rcu_head rcu; |
b448c4e3 SR |
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 | ||
68f40969 | 1189 | static bool __always_inline ftrace_hash_empty(struct ftrace_hash *hash) |
06a51d93 SR |
1190 | { |
1191 | return !hash || !hash->count; | |
1192 | } | |
1193 | ||
b448c4e3 SR |
1194 | static struct ftrace_func_entry * |
1195 | ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
1196 | { | |
1197 | unsigned long key; | |
1198 | struct ftrace_func_entry *entry; | |
1199 | struct hlist_head *hhd; | |
b448c4e3 | 1200 | |
06a51d93 | 1201 | if (ftrace_hash_empty(hash)) |
b448c4e3 SR |
1202 | return NULL; |
1203 | ||
1204 | if (hash->size_bits > 0) | |
1205 | key = hash_long(ip, hash->size_bits); | |
1206 | else | |
1207 | key = 0; | |
1208 | ||
1209 | hhd = &hash->buckets[key]; | |
1210 | ||
1bb539ca | 1211 | hlist_for_each_entry_rcu_notrace(entry, hhd, hlist) { |
b448c4e3 SR |
1212 | if (entry->ip == ip) |
1213 | return entry; | |
1214 | } | |
1215 | return NULL; | |
1216 | } | |
1217 | ||
33dc9b12 SR |
1218 | static void __add_hash_entry(struct ftrace_hash *hash, |
1219 | struct ftrace_func_entry *entry) | |
b448c4e3 | 1220 | { |
b448c4e3 SR |
1221 | struct hlist_head *hhd; |
1222 | unsigned long key; | |
1223 | ||
b448c4e3 | 1224 | if (hash->size_bits) |
33dc9b12 | 1225 | key = hash_long(entry->ip, hash->size_bits); |
b448c4e3 SR |
1226 | else |
1227 | key = 0; | |
1228 | ||
b448c4e3 SR |
1229 | hhd = &hash->buckets[key]; |
1230 | hlist_add_head(&entry->hlist, hhd); | |
1231 | hash->count++; | |
33dc9b12 SR |
1232 | } |
1233 | ||
1234 | static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) | |
1235 | { | |
1236 | struct ftrace_func_entry *entry; | |
1237 | ||
1238 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
1239 | if (!entry) | |
1240 | return -ENOMEM; | |
1241 | ||
1242 | entry->ip = ip; | |
1243 | __add_hash_entry(hash, entry); | |
b448c4e3 SR |
1244 | |
1245 | return 0; | |
1246 | } | |
1247 | ||
1248 | static void | |
33dc9b12 | 1249 | free_hash_entry(struct ftrace_hash *hash, |
b448c4e3 SR |
1250 | struct ftrace_func_entry *entry) |
1251 | { | |
1252 | hlist_del(&entry->hlist); | |
1253 | kfree(entry); | |
1254 | hash->count--; | |
1255 | } | |
1256 | ||
33dc9b12 SR |
1257 | static void |
1258 | remove_hash_entry(struct ftrace_hash *hash, | |
1259 | struct ftrace_func_entry *entry) | |
1260 | { | |
1261 | hlist_del(&entry->hlist); | |
1262 | hash->count--; | |
1263 | } | |
1264 | ||
b448c4e3 SR |
1265 | static void ftrace_hash_clear(struct ftrace_hash *hash) |
1266 | { | |
1267 | struct hlist_head *hhd; | |
b67bfe0d | 1268 | struct hlist_node *tn; |
b448c4e3 SR |
1269 | struct ftrace_func_entry *entry; |
1270 | int size = 1 << hash->size_bits; | |
1271 | int i; | |
1272 | ||
33dc9b12 SR |
1273 | if (!hash->count) |
1274 | return; | |
1275 | ||
b448c4e3 SR |
1276 | for (i = 0; i < size; i++) { |
1277 | hhd = &hash->buckets[i]; | |
b67bfe0d | 1278 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) |
33dc9b12 | 1279 | free_hash_entry(hash, entry); |
b448c4e3 SR |
1280 | } |
1281 | FTRACE_WARN_ON(hash->count); | |
1282 | } | |
1283 | ||
33dc9b12 SR |
1284 | static void free_ftrace_hash(struct ftrace_hash *hash) |
1285 | { | |
1286 | if (!hash || hash == EMPTY_HASH) | |
1287 | return; | |
1288 | ftrace_hash_clear(hash); | |
1289 | kfree(hash->buckets); | |
1290 | kfree(hash); | |
1291 | } | |
1292 | ||
07fd5515 SR |
1293 | static void __free_ftrace_hash_rcu(struct rcu_head *rcu) |
1294 | { | |
1295 | struct ftrace_hash *hash; | |
1296 | ||
1297 | hash = container_of(rcu, struct ftrace_hash, rcu); | |
1298 | free_ftrace_hash(hash); | |
1299 | } | |
1300 | ||
1301 | static void free_ftrace_hash_rcu(struct ftrace_hash *hash) | |
1302 | { | |
1303 | if (!hash || hash == EMPTY_HASH) | |
1304 | return; | |
1305 | call_rcu_sched(&hash->rcu, __free_ftrace_hash_rcu); | |
1306 | } | |
1307 | ||
5500fa51 JO |
1308 | void ftrace_free_filter(struct ftrace_ops *ops) |
1309 | { | |
f04f24fb | 1310 | ftrace_ops_init(ops); |
33b7f99c SRRH |
1311 | free_ftrace_hash(ops->func_hash->filter_hash); |
1312 | free_ftrace_hash(ops->func_hash->notrace_hash); | |
5500fa51 JO |
1313 | } |
1314 | ||
33dc9b12 SR |
1315 | static struct ftrace_hash *alloc_ftrace_hash(int size_bits) |
1316 | { | |
1317 | struct ftrace_hash *hash; | |
1318 | int size; | |
1319 | ||
1320 | hash = kzalloc(sizeof(*hash), GFP_KERNEL); | |
1321 | if (!hash) | |
1322 | return NULL; | |
1323 | ||
1324 | size = 1 << size_bits; | |
47b0edcb | 1325 | hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL); |
33dc9b12 SR |
1326 | |
1327 | if (!hash->buckets) { | |
1328 | kfree(hash); | |
1329 | return NULL; | |
1330 | } | |
1331 | ||
1332 | hash->size_bits = size_bits; | |
1333 | ||
1334 | return hash; | |
1335 | } | |
1336 | ||
1337 | static struct ftrace_hash * | |
1338 | alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) | |
1339 | { | |
1340 | struct ftrace_func_entry *entry; | |
1341 | struct ftrace_hash *new_hash; | |
33dc9b12 SR |
1342 | int size; |
1343 | int ret; | |
1344 | int i; | |
1345 | ||
1346 | new_hash = alloc_ftrace_hash(size_bits); | |
1347 | if (!new_hash) | |
1348 | return NULL; | |
1349 | ||
1350 | /* Empty hash? */ | |
06a51d93 | 1351 | if (ftrace_hash_empty(hash)) |
33dc9b12 SR |
1352 | return new_hash; |
1353 | ||
1354 | size = 1 << hash->size_bits; | |
1355 | for (i = 0; i < size; i++) { | |
b67bfe0d | 1356 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { |
33dc9b12 SR |
1357 | ret = add_hash_entry(new_hash, entry->ip); |
1358 | if (ret < 0) | |
1359 | goto free_hash; | |
1360 | } | |
1361 | } | |
1362 | ||
1363 | FTRACE_WARN_ON(new_hash->count != hash->count); | |
1364 | ||
1365 | return new_hash; | |
1366 | ||
1367 | free_hash: | |
1368 | free_ftrace_hash(new_hash); | |
1369 | return NULL; | |
1370 | } | |
1371 | ||
41fb61c2 | 1372 | static void |
84261912 | 1373 | ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, int filter_hash); |
41fb61c2 | 1374 | static void |
84261912 | 1375 | ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, int filter_hash); |
41fb61c2 | 1376 | |
f8b8be8a MH |
1377 | static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops, |
1378 | struct ftrace_hash *new_hash); | |
1379 | ||
33dc9b12 | 1380 | static int |
41fb61c2 SR |
1381 | ftrace_hash_move(struct ftrace_ops *ops, int enable, |
1382 | struct ftrace_hash **dst, struct ftrace_hash *src) | |
33dc9b12 SR |
1383 | { |
1384 | struct ftrace_func_entry *entry; | |
b67bfe0d | 1385 | struct hlist_node *tn; |
33dc9b12 | 1386 | struct hlist_head *hhd; |
07fd5515 | 1387 | struct ftrace_hash *new_hash; |
33dc9b12 SR |
1388 | int size = src->count; |
1389 | int bits = 0; | |
f8b8be8a | 1390 | int ret; |
33dc9b12 SR |
1391 | int i; |
1392 | ||
f8b8be8a MH |
1393 | /* Reject setting notrace hash on IPMODIFY ftrace_ops */ |
1394 | if (ops->flags & FTRACE_OPS_FL_IPMODIFY && !enable) | |
1395 | return -EINVAL; | |
1396 | ||
33dc9b12 SR |
1397 | /* |
1398 | * If the new source is empty, just free dst and assign it | |
1399 | * the empty_hash. | |
1400 | */ | |
1401 | if (!src->count) { | |
5c27c775 MH |
1402 | new_hash = EMPTY_HASH; |
1403 | goto update; | |
33dc9b12 SR |
1404 | } |
1405 | ||
33dc9b12 SR |
1406 | /* |
1407 | * Make the hash size about 1/2 the # found | |
1408 | */ | |
1409 | for (size /= 2; size; size >>= 1) | |
1410 | bits++; | |
1411 | ||
1412 | /* Don't allocate too much */ | |
1413 | if (bits > FTRACE_HASH_MAX_BITS) | |
1414 | bits = FTRACE_HASH_MAX_BITS; | |
1415 | ||
07fd5515 SR |
1416 | new_hash = alloc_ftrace_hash(bits); |
1417 | if (!new_hash) | |
5c27c775 | 1418 | return -ENOMEM; |
33dc9b12 SR |
1419 | |
1420 | size = 1 << src->size_bits; | |
1421 | for (i = 0; i < size; i++) { | |
1422 | hhd = &src->buckets[i]; | |
b67bfe0d | 1423 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) { |
33dc9b12 | 1424 | remove_hash_entry(src, entry); |
07fd5515 | 1425 | __add_hash_entry(new_hash, entry); |
33dc9b12 SR |
1426 | } |
1427 | } | |
1428 | ||
5c27c775 | 1429 | update: |
f8b8be8a MH |
1430 | /* Make sure this can be applied if it is IPMODIFY ftrace_ops */ |
1431 | if (enable) { | |
1432 | /* IPMODIFY should be updated only when filter_hash updating */ | |
1433 | ret = ftrace_hash_ipmodify_update(ops, new_hash); | |
1434 | if (ret < 0) { | |
1435 | free_ftrace_hash(new_hash); | |
1436 | return ret; | |
1437 | } | |
1438 | } | |
1439 | ||
5c27c775 MH |
1440 | /* |
1441 | * Remove the current set, update the hash and add | |
1442 | * them back. | |
1443 | */ | |
84261912 | 1444 | ftrace_hash_rec_disable_modify(ops, enable); |
5c27c775 | 1445 | |
07fd5515 | 1446 | rcu_assign_pointer(*dst, new_hash); |
07fd5515 | 1447 | |
84261912 | 1448 | ftrace_hash_rec_enable_modify(ops, enable); |
41fb61c2 | 1449 | |
5c27c775 | 1450 | return 0; |
33dc9b12 SR |
1451 | } |
1452 | ||
fef5aeee SRRH |
1453 | static bool hash_contains_ip(unsigned long ip, |
1454 | struct ftrace_ops_hash *hash) | |
1455 | { | |
1456 | /* | |
1457 | * The function record is a match if it exists in the filter | |
1458 | * hash and not in the notrace hash. Note, an emty hash is | |
1459 | * considered a match for the filter hash, but an empty | |
1460 | * notrace hash is considered not in the notrace hash. | |
1461 | */ | |
1462 | return (ftrace_hash_empty(hash->filter_hash) || | |
1463 | ftrace_lookup_ip(hash->filter_hash, ip)) && | |
1464 | (ftrace_hash_empty(hash->notrace_hash) || | |
1465 | !ftrace_lookup_ip(hash->notrace_hash, ip)); | |
1466 | } | |
1467 | ||
b848914c SR |
1468 | /* |
1469 | * Test the hashes for this ops to see if we want to call | |
1470 | * the ops->func or not. | |
1471 | * | |
1472 | * It's a match if the ip is in the ops->filter_hash or | |
1473 | * the filter_hash does not exist or is empty, | |
1474 | * AND | |
1475 | * the ip is not in the ops->notrace_hash. | |
cdbe61bf SR |
1476 | * |
1477 | * This needs to be called with preemption disabled as | |
1478 | * the hashes are freed with call_rcu_sched(). | |
b848914c SR |
1479 | */ |
1480 | static int | |
195a8afc | 1481 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs) |
b848914c | 1482 | { |
fef5aeee | 1483 | struct ftrace_ops_hash hash; |
b848914c SR |
1484 | int ret; |
1485 | ||
195a8afc SRRH |
1486 | #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
1487 | /* | |
1488 | * There's a small race when adding ops that the ftrace handler | |
1489 | * that wants regs, may be called without them. We can not | |
1490 | * allow that handler to be called if regs is NULL. | |
1491 | */ | |
1492 | if (regs == NULL && (ops->flags & FTRACE_OPS_FL_SAVE_REGS)) | |
1493 | return 0; | |
1494 | #endif | |
1495 | ||
fef5aeee SRRH |
1496 | hash.filter_hash = rcu_dereference_raw_notrace(ops->func_hash->filter_hash); |
1497 | hash.notrace_hash = rcu_dereference_raw_notrace(ops->func_hash->notrace_hash); | |
b848914c | 1498 | |
fef5aeee | 1499 | if (hash_contains_ip(ip, &hash)) |
b848914c SR |
1500 | ret = 1; |
1501 | else | |
1502 | ret = 0; | |
b848914c SR |
1503 | |
1504 | return ret; | |
1505 | } | |
1506 | ||
493762fc SR |
1507 | /* |
1508 | * This is a double for. Do not use 'break' to break out of the loop, | |
1509 | * you must use a goto. | |
1510 | */ | |
1511 | #define do_for_each_ftrace_rec(pg, rec) \ | |
1512 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
1513 | int _____i; \ | |
1514 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
1515 | rec = &pg->records[_____i]; | |
1516 | ||
1517 | #define while_for_each_ftrace_rec() \ | |
1518 | } \ | |
1519 | } | |
1520 | ||
5855fead SR |
1521 | |
1522 | static int ftrace_cmp_recs(const void *a, const void *b) | |
1523 | { | |
a650e02a SR |
1524 | const struct dyn_ftrace *key = a; |
1525 | const struct dyn_ftrace *rec = b; | |
5855fead | 1526 | |
a650e02a | 1527 | if (key->flags < rec->ip) |
5855fead | 1528 | return -1; |
a650e02a SR |
1529 | if (key->ip >= rec->ip + MCOUNT_INSN_SIZE) |
1530 | return 1; | |
5855fead SR |
1531 | return 0; |
1532 | } | |
1533 | ||
04cf31a7 ME |
1534 | /** |
1535 | * ftrace_location_range - return the first address of a traced location | |
1536 | * if it touches the given ip range | |
1537 | * @start: start of range to search. | |
1538 | * @end: end of range to search (inclusive). @end points to the last byte | |
1539 | * to check. | |
1540 | * | |
1541 | * Returns rec->ip if the related ftrace location is a least partly within | |
1542 | * the given address range. That is, the first address of the instruction | |
1543 | * that is either a NOP or call to the function tracer. It checks the ftrace | |
1544 | * internal tables to determine if the address belongs or not. | |
1545 | */ | |
1546 | unsigned long ftrace_location_range(unsigned long start, unsigned long end) | |
c88fd863 SR |
1547 | { |
1548 | struct ftrace_page *pg; | |
1549 | struct dyn_ftrace *rec; | |
5855fead | 1550 | struct dyn_ftrace key; |
c88fd863 | 1551 | |
a650e02a SR |
1552 | key.ip = start; |
1553 | key.flags = end; /* overload flags, as it is unsigned long */ | |
5855fead SR |
1554 | |
1555 | for (pg = ftrace_pages_start; pg; pg = pg->next) { | |
a650e02a SR |
1556 | if (end < pg->records[0].ip || |
1557 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) | |
9644302e | 1558 | continue; |
5855fead SR |
1559 | rec = bsearch(&key, pg->records, pg->index, |
1560 | sizeof(struct dyn_ftrace), | |
1561 | ftrace_cmp_recs); | |
1562 | if (rec) | |
f0cf973a | 1563 | return rec->ip; |
5855fead | 1564 | } |
c88fd863 SR |
1565 | |
1566 | return 0; | |
1567 | } | |
1568 | ||
a650e02a SR |
1569 | /** |
1570 | * ftrace_location - return true if the ip giving is a traced location | |
1571 | * @ip: the instruction pointer to check | |
1572 | * | |
f0cf973a | 1573 | * Returns rec->ip if @ip given is a pointer to a ftrace location. |
a650e02a SR |
1574 | * That is, the instruction that is either a NOP or call to |
1575 | * the function tracer. It checks the ftrace internal tables to | |
1576 | * determine if the address belongs or not. | |
1577 | */ | |
f0cf973a | 1578 | unsigned long ftrace_location(unsigned long ip) |
a650e02a SR |
1579 | { |
1580 | return ftrace_location_range(ip, ip); | |
1581 | } | |
1582 | ||
1583 | /** | |
1584 | * ftrace_text_reserved - return true if range contains an ftrace location | |
1585 | * @start: start of range to search | |
1586 | * @end: end of range to search (inclusive). @end points to the last byte to check. | |
1587 | * | |
1588 | * Returns 1 if @start and @end contains a ftrace location. | |
1589 | * That is, the instruction that is either a NOP or call to | |
1590 | * the function tracer. It checks the ftrace internal tables to | |
1591 | * determine if the address belongs or not. | |
1592 | */ | |
d88471cb | 1593 | int ftrace_text_reserved(const void *start, const void *end) |
a650e02a | 1594 | { |
f0cf973a SR |
1595 | unsigned long ret; |
1596 | ||
1597 | ret = ftrace_location_range((unsigned long)start, | |
1598 | (unsigned long)end); | |
1599 | ||
1600 | return (int)!!ret; | |
a650e02a SR |
1601 | } |
1602 | ||
4fbb48cb SRRH |
1603 | /* Test if ops registered to this rec needs regs */ |
1604 | static bool test_rec_ops_needs_regs(struct dyn_ftrace *rec) | |
1605 | { | |
1606 | struct ftrace_ops *ops; | |
1607 | bool keep_regs = false; | |
1608 | ||
1609 | for (ops = ftrace_ops_list; | |
1610 | ops != &ftrace_list_end; ops = ops->next) { | |
1611 | /* pass rec in as regs to have non-NULL val */ | |
1612 | if (ftrace_ops_test(ops, rec->ip, rec)) { | |
1613 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) { | |
1614 | keep_regs = true; | |
1615 | break; | |
1616 | } | |
1617 | } | |
1618 | } | |
1619 | ||
1620 | return keep_regs; | |
1621 | } | |
1622 | ||
84b6d3e6 | 1623 | static bool __ftrace_hash_rec_update(struct ftrace_ops *ops, |
ed926f9b SR |
1624 | int filter_hash, |
1625 | bool inc) | |
1626 | { | |
1627 | struct ftrace_hash *hash; | |
1628 | struct ftrace_hash *other_hash; | |
1629 | struct ftrace_page *pg; | |
1630 | struct dyn_ftrace *rec; | |
84b6d3e6 | 1631 | bool update = false; |
ed926f9b SR |
1632 | int count = 0; |
1633 | int all = 0; | |
1634 | ||
1635 | /* Only update if the ops has been registered */ | |
1636 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
84b6d3e6 | 1637 | return false; |
ed926f9b SR |
1638 | |
1639 | /* | |
1640 | * In the filter_hash case: | |
1641 | * If the count is zero, we update all records. | |
1642 | * Otherwise we just update the items in the hash. | |
1643 | * | |
1644 | * In the notrace_hash case: | |
1645 | * We enable the update in the hash. | |
1646 | * As disabling notrace means enabling the tracing, | |
1647 | * and enabling notrace means disabling, the inc variable | |
1648 | * gets inversed. | |
1649 | */ | |
1650 | if (filter_hash) { | |
33b7f99c SRRH |
1651 | hash = ops->func_hash->filter_hash; |
1652 | other_hash = ops->func_hash->notrace_hash; | |
06a51d93 | 1653 | if (ftrace_hash_empty(hash)) |
ed926f9b SR |
1654 | all = 1; |
1655 | } else { | |
1656 | inc = !inc; | |
33b7f99c SRRH |
1657 | hash = ops->func_hash->notrace_hash; |
1658 | other_hash = ops->func_hash->filter_hash; | |
ed926f9b SR |
1659 | /* |
1660 | * If the notrace hash has no items, | |
1661 | * then there's nothing to do. | |
1662 | */ | |
06a51d93 | 1663 | if (ftrace_hash_empty(hash)) |
84b6d3e6 | 1664 | return false; |
ed926f9b SR |
1665 | } |
1666 | ||
1667 | do_for_each_ftrace_rec(pg, rec) { | |
1668 | int in_other_hash = 0; | |
1669 | int in_hash = 0; | |
1670 | int match = 0; | |
1671 | ||
b7ffffbb SRRH |
1672 | if (rec->flags & FTRACE_FL_DISABLED) |
1673 | continue; | |
1674 | ||
ed926f9b SR |
1675 | if (all) { |
1676 | /* | |
1677 | * Only the filter_hash affects all records. | |
1678 | * Update if the record is not in the notrace hash. | |
1679 | */ | |
b848914c | 1680 | if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip)) |
ed926f9b SR |
1681 | match = 1; |
1682 | } else { | |
06a51d93 SR |
1683 | in_hash = !!ftrace_lookup_ip(hash, rec->ip); |
1684 | in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip); | |
ed926f9b SR |
1685 | |
1686 | /* | |
19eab4a4 SRRH |
1687 | * If filter_hash is set, we want to match all functions |
1688 | * that are in the hash but not in the other hash. | |
ed926f9b | 1689 | * |
19eab4a4 SRRH |
1690 | * If filter_hash is not set, then we are decrementing. |
1691 | * That means we match anything that is in the hash | |
1692 | * and also in the other_hash. That is, we need to turn | |
1693 | * off functions in the other hash because they are disabled | |
1694 | * by this hash. | |
ed926f9b SR |
1695 | */ |
1696 | if (filter_hash && in_hash && !in_other_hash) | |
1697 | match = 1; | |
1698 | else if (!filter_hash && in_hash && | |
06a51d93 | 1699 | (in_other_hash || ftrace_hash_empty(other_hash))) |
ed926f9b SR |
1700 | match = 1; |
1701 | } | |
1702 | if (!match) | |
1703 | continue; | |
1704 | ||
1705 | if (inc) { | |
1706 | rec->flags++; | |
0376bde1 | 1707 | if (FTRACE_WARN_ON(ftrace_rec_count(rec) == FTRACE_REF_MAX)) |
84b6d3e6 | 1708 | return false; |
79922b80 SRRH |
1709 | |
1710 | /* | |
1711 | * If there's only a single callback registered to a | |
1712 | * function, and the ops has a trampoline registered | |
1713 | * for it, then we can call it directly. | |
1714 | */ | |
fef5aeee | 1715 | if (ftrace_rec_count(rec) == 1 && ops->trampoline) |
79922b80 | 1716 | rec->flags |= FTRACE_FL_TRAMP; |
fef5aeee | 1717 | else |
79922b80 SRRH |
1718 | /* |
1719 | * If we are adding another function callback | |
1720 | * to this function, and the previous had a | |
bce0b6c5 SRRH |
1721 | * custom trampoline in use, then we need to go |
1722 | * back to the default trampoline. | |
79922b80 | 1723 | */ |
fef5aeee | 1724 | rec->flags &= ~FTRACE_FL_TRAMP; |
79922b80 | 1725 | |
08f6fba5 SR |
1726 | /* |
1727 | * If any ops wants regs saved for this function | |
1728 | * then all ops will get saved regs. | |
1729 | */ | |
1730 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) | |
1731 | rec->flags |= FTRACE_FL_REGS; | |
ed926f9b | 1732 | } else { |
0376bde1 | 1733 | if (FTRACE_WARN_ON(ftrace_rec_count(rec) == 0)) |
84b6d3e6 | 1734 | return false; |
ed926f9b | 1735 | rec->flags--; |
79922b80 | 1736 | |
4fbb48cb SRRH |
1737 | /* |
1738 | * If the rec had REGS enabled and the ops that is | |
1739 | * being removed had REGS set, then see if there is | |
1740 | * still any ops for this record that wants regs. | |
1741 | * If not, we can stop recording them. | |
1742 | */ | |
0376bde1 | 1743 | if (ftrace_rec_count(rec) > 0 && |
4fbb48cb SRRH |
1744 | rec->flags & FTRACE_FL_REGS && |
1745 | ops->flags & FTRACE_OPS_FL_SAVE_REGS) { | |
1746 | if (!test_rec_ops_needs_regs(rec)) | |
1747 | rec->flags &= ~FTRACE_FL_REGS; | |
1748 | } | |
79922b80 | 1749 | |
fef5aeee SRRH |
1750 | /* |
1751 | * If the rec had TRAMP enabled, then it needs to | |
1752 | * be cleared. As TRAMP can only be enabled iff | |
1753 | * there is only a single ops attached to it. | |
1754 | * In otherwords, always disable it on decrementing. | |
1755 | * In the future, we may set it if rec count is | |
1756 | * decremented to one, and the ops that is left | |
1757 | * has a trampoline. | |
1758 | */ | |
1759 | rec->flags &= ~FTRACE_FL_TRAMP; | |
1760 | ||
79922b80 SRRH |
1761 | /* |
1762 | * flags will be cleared in ftrace_check_record() | |
1763 | * if rec count is zero. | |
1764 | */ | |
ed926f9b SR |
1765 | } |
1766 | count++; | |
84b6d3e6 JO |
1767 | |
1768 | /* Must match FTRACE_UPDATE_CALLS in ftrace_modify_all_code() */ | |
1769 | update |= ftrace_test_record(rec, 1) != FTRACE_UPDATE_IGNORE; | |
1770 | ||
ed926f9b SR |
1771 | /* Shortcut, if we handled all records, we are done. */ |
1772 | if (!all && count == hash->count) | |
84b6d3e6 | 1773 | return update; |
ed926f9b | 1774 | } while_for_each_ftrace_rec(); |
84b6d3e6 JO |
1775 | |
1776 | return update; | |
ed926f9b SR |
1777 | } |
1778 | ||
84b6d3e6 | 1779 | static bool ftrace_hash_rec_disable(struct ftrace_ops *ops, |
ed926f9b SR |
1780 | int filter_hash) |
1781 | { | |
84b6d3e6 | 1782 | return __ftrace_hash_rec_update(ops, filter_hash, 0); |
ed926f9b SR |
1783 | } |
1784 | ||
84b6d3e6 | 1785 | static bool ftrace_hash_rec_enable(struct ftrace_ops *ops, |
ed926f9b SR |
1786 | int filter_hash) |
1787 | { | |
84b6d3e6 | 1788 | return __ftrace_hash_rec_update(ops, filter_hash, 1); |
ed926f9b SR |
1789 | } |
1790 | ||
84261912 SRRH |
1791 | static void ftrace_hash_rec_update_modify(struct ftrace_ops *ops, |
1792 | int filter_hash, int inc) | |
1793 | { | |
1794 | struct ftrace_ops *op; | |
1795 | ||
1796 | __ftrace_hash_rec_update(ops, filter_hash, inc); | |
1797 | ||
1798 | if (ops->func_hash != &global_ops.local_hash) | |
1799 | return; | |
1800 | ||
1801 | /* | |
1802 | * If the ops shares the global_ops hash, then we need to update | |
1803 | * all ops that are enabled and use this hash. | |
1804 | */ | |
1805 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
1806 | /* Already done */ | |
1807 | if (op == ops) | |
1808 | continue; | |
1809 | if (op->func_hash == &global_ops.local_hash) | |
1810 | __ftrace_hash_rec_update(op, filter_hash, inc); | |
1811 | } while_for_each_ftrace_op(op); | |
1812 | } | |
1813 | ||
1814 | static void ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, | |
1815 | int filter_hash) | |
1816 | { | |
1817 | ftrace_hash_rec_update_modify(ops, filter_hash, 0); | |
1818 | } | |
1819 | ||
1820 | static void ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, | |
1821 | int filter_hash) | |
1822 | { | |
1823 | ftrace_hash_rec_update_modify(ops, filter_hash, 1); | |
1824 | } | |
1825 | ||
f8b8be8a MH |
1826 | /* |
1827 | * Try to update IPMODIFY flag on each ftrace_rec. Return 0 if it is OK | |
1828 | * or no-needed to update, -EBUSY if it detects a conflict of the flag | |
1829 | * on a ftrace_rec, and -EINVAL if the new_hash tries to trace all recs. | |
1830 | * Note that old_hash and new_hash has below meanings | |
1831 | * - If the hash is NULL, it hits all recs (if IPMODIFY is set, this is rejected) | |
1832 | * - If the hash is EMPTY_HASH, it hits nothing | |
1833 | * - Anything else hits the recs which match the hash entries. | |
1834 | */ | |
1835 | static int __ftrace_hash_update_ipmodify(struct ftrace_ops *ops, | |
1836 | struct ftrace_hash *old_hash, | |
1837 | struct ftrace_hash *new_hash) | |
1838 | { | |
1839 | struct ftrace_page *pg; | |
1840 | struct dyn_ftrace *rec, *end = NULL; | |
1841 | int in_old, in_new; | |
1842 | ||
1843 | /* Only update if the ops has been registered */ | |
1844 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
1845 | return 0; | |
1846 | ||
1847 | if (!(ops->flags & FTRACE_OPS_FL_IPMODIFY)) | |
1848 | return 0; | |
1849 | ||
1850 | /* | |
1851 | * Since the IPMODIFY is a very address sensitive action, we do not | |
1852 | * allow ftrace_ops to set all functions to new hash. | |
1853 | */ | |
1854 | if (!new_hash || !old_hash) | |
1855 | return -EINVAL; | |
1856 | ||
1857 | /* Update rec->flags */ | |
1858 | do_for_each_ftrace_rec(pg, rec) { | |
1859 | /* We need to update only differences of filter_hash */ | |
1860 | in_old = !!ftrace_lookup_ip(old_hash, rec->ip); | |
1861 | in_new = !!ftrace_lookup_ip(new_hash, rec->ip); | |
1862 | if (in_old == in_new) | |
1863 | continue; | |
1864 | ||
1865 | if (in_new) { | |
1866 | /* New entries must ensure no others are using it */ | |
1867 | if (rec->flags & FTRACE_FL_IPMODIFY) | |
1868 | goto rollback; | |
1869 | rec->flags |= FTRACE_FL_IPMODIFY; | |
1870 | } else /* Removed entry */ | |
1871 | rec->flags &= ~FTRACE_FL_IPMODIFY; | |
1872 | } while_for_each_ftrace_rec(); | |
1873 | ||
1874 | return 0; | |
1875 | ||
1876 | rollback: | |
1877 | end = rec; | |
1878 | ||
1879 | /* Roll back what we did above */ | |
1880 | do_for_each_ftrace_rec(pg, rec) { | |
1881 | if (rec == end) | |
1882 | goto err_out; | |
1883 | ||
1884 | in_old = !!ftrace_lookup_ip(old_hash, rec->ip); | |
1885 | in_new = !!ftrace_lookup_ip(new_hash, rec->ip); | |
1886 | if (in_old == in_new) | |
1887 | continue; | |
1888 | ||
1889 | if (in_new) | |
1890 | rec->flags &= ~FTRACE_FL_IPMODIFY; | |
1891 | else | |
1892 | rec->flags |= FTRACE_FL_IPMODIFY; | |
1893 | } while_for_each_ftrace_rec(); | |
1894 | ||
1895 | err_out: | |
1896 | return -EBUSY; | |
1897 | } | |
1898 | ||
1899 | static int ftrace_hash_ipmodify_enable(struct ftrace_ops *ops) | |
1900 | { | |
1901 | struct ftrace_hash *hash = ops->func_hash->filter_hash; | |
1902 | ||
1903 | if (ftrace_hash_empty(hash)) | |
1904 | hash = NULL; | |
1905 | ||
1906 | return __ftrace_hash_update_ipmodify(ops, EMPTY_HASH, hash); | |
1907 | } | |
1908 | ||
1909 | /* Disabling always succeeds */ | |
1910 | static void ftrace_hash_ipmodify_disable(struct ftrace_ops *ops) | |
1911 | { | |
1912 | struct ftrace_hash *hash = ops->func_hash->filter_hash; | |
1913 | ||
1914 | if (ftrace_hash_empty(hash)) | |
1915 | hash = NULL; | |
1916 | ||
1917 | __ftrace_hash_update_ipmodify(ops, hash, EMPTY_HASH); | |
1918 | } | |
1919 | ||
1920 | static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops, | |
1921 | struct ftrace_hash *new_hash) | |
1922 | { | |
1923 | struct ftrace_hash *old_hash = ops->func_hash->filter_hash; | |
1924 | ||
1925 | if (ftrace_hash_empty(old_hash)) | |
1926 | old_hash = NULL; | |
1927 | ||
1928 | if (ftrace_hash_empty(new_hash)) | |
1929 | new_hash = NULL; | |
1930 | ||
1931 | return __ftrace_hash_update_ipmodify(ops, old_hash, new_hash); | |
1932 | } | |
1933 | ||
b05086c7 | 1934 | static void print_ip_ins(const char *fmt, const unsigned char *p) |
b17e8a37 SR |
1935 | { |
1936 | int i; | |
1937 | ||
1938 | printk(KERN_CONT "%s", fmt); | |
1939 | ||
1940 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
1941 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
1942 | } | |
1943 | ||
4fd3279b SRRH |
1944 | static struct ftrace_ops * |
1945 | ftrace_find_tramp_ops_any(struct dyn_ftrace *rec); | |
39daa7b9 SRRH |
1946 | static struct ftrace_ops * |
1947 | ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, struct ftrace_ops *ops); | |
4fd3279b | 1948 | |
02a392a0 | 1949 | enum ftrace_bug_type ftrace_bug_type; |
b05086c7 | 1950 | const void *ftrace_expected; |
02a392a0 SRRH |
1951 | |
1952 | static void print_bug_type(void) | |
1953 | { | |
1954 | switch (ftrace_bug_type) { | |
1955 | case FTRACE_BUG_UNKNOWN: | |
1956 | break; | |
1957 | case FTRACE_BUG_INIT: | |
1958 | pr_info("Initializing ftrace call sites\n"); | |
1959 | break; | |
1960 | case FTRACE_BUG_NOP: | |
1961 | pr_info("Setting ftrace call site to NOP\n"); | |
1962 | break; | |
1963 | case FTRACE_BUG_CALL: | |
1964 | pr_info("Setting ftrace call site to call ftrace function\n"); | |
1965 | break; | |
1966 | case FTRACE_BUG_UPDATE: | |
1967 | pr_info("Updating ftrace call site to call a different ftrace function\n"); | |
1968 | break; | |
1969 | } | |
1970 | } | |
1971 | ||
c88fd863 SR |
1972 | /** |
1973 | * ftrace_bug - report and shutdown function tracer | |
1974 | * @failed: The failed type (EFAULT, EINVAL, EPERM) | |
4fd3279b | 1975 | * @rec: The record that failed |
c88fd863 SR |
1976 | * |
1977 | * The arch code that enables or disables the function tracing | |
1978 | * can call ftrace_bug() when it has detected a problem in | |
1979 | * modifying the code. @failed should be one of either: | |
1980 | * EFAULT - if the problem happens on reading the @ip address | |
1981 | * EINVAL - if what is read at @ip is not what was expected | |
1982 | * EPERM - if the problem happens on writting to the @ip address | |
1983 | */ | |
4fd3279b | 1984 | void ftrace_bug(int failed, struct dyn_ftrace *rec) |
b17e8a37 | 1985 | { |
4fd3279b SRRH |
1986 | unsigned long ip = rec ? rec->ip : 0; |
1987 | ||
b17e8a37 SR |
1988 | switch (failed) { |
1989 | case -EFAULT: | |
1990 | FTRACE_WARN_ON_ONCE(1); | |
1991 | pr_info("ftrace faulted on modifying "); | |
1992 | print_ip_sym(ip); | |
1993 | break; | |
1994 | case -EINVAL: | |
1995 | FTRACE_WARN_ON_ONCE(1); | |
1996 | pr_info("ftrace failed to modify "); | |
1997 | print_ip_sym(ip); | |
b05086c7 | 1998 | print_ip_ins(" actual: ", (unsigned char *)ip); |
4fd3279b | 1999 | pr_cont("\n"); |
b05086c7 SRRH |
2000 | if (ftrace_expected) { |
2001 | print_ip_ins(" expected: ", ftrace_expected); | |
2002 | pr_cont("\n"); | |
2003 | } | |
b17e8a37 SR |
2004 | break; |
2005 | case -EPERM: | |
2006 | FTRACE_WARN_ON_ONCE(1); | |
2007 | pr_info("ftrace faulted on writing "); | |
2008 | print_ip_sym(ip); | |
2009 | break; | |
2010 | default: | |
2011 | FTRACE_WARN_ON_ONCE(1); | |
2012 | pr_info("ftrace faulted on unknown error "); | |
2013 | print_ip_sym(ip); | |
2014 | } | |
02a392a0 | 2015 | print_bug_type(); |
4fd3279b SRRH |
2016 | if (rec) { |
2017 | struct ftrace_ops *ops = NULL; | |
2018 | ||
2019 | pr_info("ftrace record flags: %lx\n", rec->flags); | |
2020 | pr_cont(" (%ld)%s", ftrace_rec_count(rec), | |
2021 | rec->flags & FTRACE_FL_REGS ? " R" : " "); | |
2022 | if (rec->flags & FTRACE_FL_TRAMP_EN) { | |
2023 | ops = ftrace_find_tramp_ops_any(rec); | |
39daa7b9 SRRH |
2024 | if (ops) { |
2025 | do { | |
2026 | pr_cont("\ttramp: %pS (%pS)", | |
2027 | (void *)ops->trampoline, | |
2028 | (void *)ops->func); | |
2029 | ops = ftrace_find_tramp_ops_next(rec, ops); | |
2030 | } while (ops); | |
2031 | } else | |
4fd3279b SRRH |
2032 | pr_cont("\ttramp: ERROR!"); |
2033 | ||
2034 | } | |
2035 | ip = ftrace_get_addr_curr(rec); | |
39daa7b9 | 2036 | pr_cont("\n expected tramp: %lx\n", ip); |
4fd3279b | 2037 | } |
b17e8a37 SR |
2038 | } |
2039 | ||
c88fd863 | 2040 | static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update) |
5072c59f | 2041 | { |
64fbcd16 | 2042 | unsigned long flag = 0UL; |
e7d3737e | 2043 | |
02a392a0 SRRH |
2044 | ftrace_bug_type = FTRACE_BUG_UNKNOWN; |
2045 | ||
b7ffffbb SRRH |
2046 | if (rec->flags & FTRACE_FL_DISABLED) |
2047 | return FTRACE_UPDATE_IGNORE; | |
2048 | ||
982c350b | 2049 | /* |
30fb6aa7 | 2050 | * If we are updating calls: |
982c350b | 2051 | * |
ed926f9b SR |
2052 | * If the record has a ref count, then we need to enable it |
2053 | * because someone is using it. | |
982c350b | 2054 | * |
ed926f9b SR |
2055 | * Otherwise we make sure its disabled. |
2056 | * | |
30fb6aa7 | 2057 | * If we are disabling calls, then disable all records that |
ed926f9b | 2058 | * are enabled. |
982c350b | 2059 | */ |
0376bde1 | 2060 | if (enable && ftrace_rec_count(rec)) |
ed926f9b | 2061 | flag = FTRACE_FL_ENABLED; |
982c350b | 2062 | |
08f6fba5 | 2063 | /* |
79922b80 SRRH |
2064 | * If enabling and the REGS flag does not match the REGS_EN, or |
2065 | * the TRAMP flag doesn't match the TRAMP_EN, then do not ignore | |
2066 | * this record. Set flags to fail the compare against ENABLED. | |
08f6fba5 | 2067 | */ |
79922b80 SRRH |
2068 | if (flag) { |
2069 | if (!(rec->flags & FTRACE_FL_REGS) != | |
2070 | !(rec->flags & FTRACE_FL_REGS_EN)) | |
2071 | flag |= FTRACE_FL_REGS; | |
2072 | ||
2073 | if (!(rec->flags & FTRACE_FL_TRAMP) != | |
2074 | !(rec->flags & FTRACE_FL_TRAMP_EN)) | |
2075 | flag |= FTRACE_FL_TRAMP; | |
2076 | } | |
08f6fba5 | 2077 | |
64fbcd16 XG |
2078 | /* If the state of this record hasn't changed, then do nothing */ |
2079 | if ((rec->flags & FTRACE_FL_ENABLED) == flag) | |
c88fd863 | 2080 | return FTRACE_UPDATE_IGNORE; |
982c350b | 2081 | |
64fbcd16 | 2082 | if (flag) { |
08f6fba5 SR |
2083 | /* Save off if rec is being enabled (for return value) */ |
2084 | flag ^= rec->flags & FTRACE_FL_ENABLED; | |
2085 | ||
2086 | if (update) { | |
c88fd863 | 2087 | rec->flags |= FTRACE_FL_ENABLED; |
08f6fba5 SR |
2088 | if (flag & FTRACE_FL_REGS) { |
2089 | if (rec->flags & FTRACE_FL_REGS) | |
2090 | rec->flags |= FTRACE_FL_REGS_EN; | |
2091 | else | |
2092 | rec->flags &= ~FTRACE_FL_REGS_EN; | |
2093 | } | |
79922b80 SRRH |
2094 | if (flag & FTRACE_FL_TRAMP) { |
2095 | if (rec->flags & FTRACE_FL_TRAMP) | |
2096 | rec->flags |= FTRACE_FL_TRAMP_EN; | |
2097 | else | |
2098 | rec->flags &= ~FTRACE_FL_TRAMP_EN; | |
2099 | } | |
08f6fba5 SR |
2100 | } |
2101 | ||
2102 | /* | |
2103 | * If this record is being updated from a nop, then | |
2104 | * return UPDATE_MAKE_CALL. | |
08f6fba5 SR |
2105 | * Otherwise, |
2106 | * return UPDATE_MODIFY_CALL to tell the caller to convert | |
f1b2f2bd | 2107 | * from the save regs, to a non-save regs function or |
79922b80 | 2108 | * vice versa, or from a trampoline call. |
08f6fba5 | 2109 | */ |
02a392a0 SRRH |
2110 | if (flag & FTRACE_FL_ENABLED) { |
2111 | ftrace_bug_type = FTRACE_BUG_CALL; | |
08f6fba5 | 2112 | return FTRACE_UPDATE_MAKE_CALL; |
02a392a0 | 2113 | } |
f1b2f2bd | 2114 | |
02a392a0 | 2115 | ftrace_bug_type = FTRACE_BUG_UPDATE; |
f1b2f2bd | 2116 | return FTRACE_UPDATE_MODIFY_CALL; |
c88fd863 SR |
2117 | } |
2118 | ||
08f6fba5 SR |
2119 | if (update) { |
2120 | /* If there's no more users, clear all flags */ | |
0376bde1 | 2121 | if (!ftrace_rec_count(rec)) |
08f6fba5 SR |
2122 | rec->flags = 0; |
2123 | else | |
b24d443b SRRH |
2124 | /* |
2125 | * Just disable the record, but keep the ops TRAMP | |
2126 | * and REGS states. The _EN flags must be disabled though. | |
2127 | */ | |
2128 | rec->flags &= ~(FTRACE_FL_ENABLED | FTRACE_FL_TRAMP_EN | | |
2129 | FTRACE_FL_REGS_EN); | |
08f6fba5 | 2130 | } |
c88fd863 | 2131 | |
02a392a0 | 2132 | ftrace_bug_type = FTRACE_BUG_NOP; |
c88fd863 SR |
2133 | return FTRACE_UPDATE_MAKE_NOP; |
2134 | } | |
2135 | ||
2136 | /** | |
2137 | * ftrace_update_record, set a record that now is tracing or not | |
2138 | * @rec: the record to update | |
2139 | * @enable: set to 1 if the record is tracing, zero to force disable | |
2140 | * | |
2141 | * The records that represent all functions that can be traced need | |
2142 | * to be updated when tracing has been enabled. | |
2143 | */ | |
2144 | int ftrace_update_record(struct dyn_ftrace *rec, int enable) | |
2145 | { | |
2146 | return ftrace_check_record(rec, enable, 1); | |
2147 | } | |
2148 | ||
2149 | /** | |
2150 | * ftrace_test_record, check if the record has been enabled or not | |
2151 | * @rec: the record to test | |
2152 | * @enable: set to 1 to check if enabled, 0 if it is disabled | |
2153 | * | |
2154 | * The arch code may need to test if a record is already set to | |
2155 | * tracing to determine how to modify the function code that it | |
2156 | * represents. | |
2157 | */ | |
2158 | int ftrace_test_record(struct dyn_ftrace *rec, int enable) | |
2159 | { | |
2160 | return ftrace_check_record(rec, enable, 0); | |
2161 | } | |
2162 | ||
5fecaa04 SRRH |
2163 | static struct ftrace_ops * |
2164 | ftrace_find_tramp_ops_any(struct dyn_ftrace *rec) | |
2165 | { | |
2166 | struct ftrace_ops *op; | |
fef5aeee | 2167 | unsigned long ip = rec->ip; |
5fecaa04 SRRH |
2168 | |
2169 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
2170 | ||
2171 | if (!op->trampoline) | |
2172 | continue; | |
2173 | ||
fef5aeee | 2174 | if (hash_contains_ip(ip, op->func_hash)) |
5fecaa04 SRRH |
2175 | return op; |
2176 | } while_for_each_ftrace_op(op); | |
2177 | ||
2178 | return NULL; | |
2179 | } | |
2180 | ||
39daa7b9 SRRH |
2181 | static struct ftrace_ops * |
2182 | ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, | |
2183 | struct ftrace_ops *op) | |
2184 | { | |
2185 | unsigned long ip = rec->ip; | |
2186 | ||
2187 | while_for_each_ftrace_op(op) { | |
2188 | ||
2189 | if (!op->trampoline) | |
2190 | continue; | |
2191 | ||
2192 | if (hash_contains_ip(ip, op->func_hash)) | |
2193 | return op; | |
2194 | } | |
2195 | ||
2196 | return NULL; | |
2197 | } | |
2198 | ||
79922b80 SRRH |
2199 | static struct ftrace_ops * |
2200 | ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec) | |
2201 | { | |
2202 | struct ftrace_ops *op; | |
fef5aeee | 2203 | unsigned long ip = rec->ip; |
79922b80 | 2204 | |
fef5aeee SRRH |
2205 | /* |
2206 | * Need to check removed ops first. | |
2207 | * If they are being removed, and this rec has a tramp, | |
2208 | * and this rec is in the ops list, then it would be the | |
2209 | * one with the tramp. | |
2210 | */ | |
2211 | if (removed_ops) { | |
2212 | if (hash_contains_ip(ip, &removed_ops->old_hash)) | |
79922b80 SRRH |
2213 | return removed_ops; |
2214 | } | |
2215 | ||
fef5aeee SRRH |
2216 | /* |
2217 | * Need to find the current trampoline for a rec. | |
2218 | * Now, a trampoline is only attached to a rec if there | |
2219 | * was a single 'ops' attached to it. But this can be called | |
2220 | * when we are adding another op to the rec or removing the | |
2221 | * current one. Thus, if the op is being added, we can | |
2222 | * ignore it because it hasn't attached itself to the rec | |
4fc40904 SRRH |
2223 | * yet. |
2224 | * | |
2225 | * If an ops is being modified (hooking to different functions) | |
2226 | * then we don't care about the new functions that are being | |
2227 | * added, just the old ones (that are probably being removed). | |
2228 | * | |
2229 | * If we are adding an ops to a function that already is using | |
2230 | * a trampoline, it needs to be removed (trampolines are only | |
2231 | * for single ops connected), then an ops that is not being | |
2232 | * modified also needs to be checked. | |
fef5aeee | 2233 | */ |
79922b80 | 2234 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
fef5aeee SRRH |
2235 | |
2236 | if (!op->trampoline) | |
2237 | continue; | |
2238 | ||
2239 | /* | |
2240 | * If the ops is being added, it hasn't gotten to | |
2241 | * the point to be removed from this tree yet. | |
2242 | */ | |
2243 | if (op->flags & FTRACE_OPS_FL_ADDING) | |
79922b80 SRRH |
2244 | continue; |
2245 | ||
4fc40904 | 2246 | |
fef5aeee | 2247 | /* |
4fc40904 SRRH |
2248 | * If the ops is being modified and is in the old |
2249 | * hash, then it is probably being removed from this | |
2250 | * function. | |
fef5aeee | 2251 | */ |
fef5aeee SRRH |
2252 | if ((op->flags & FTRACE_OPS_FL_MODIFYING) && |
2253 | hash_contains_ip(ip, &op->old_hash)) | |
79922b80 | 2254 | return op; |
4fc40904 SRRH |
2255 | /* |
2256 | * If the ops is not being added or modified, and it's | |
2257 | * in its normal filter hash, then this must be the one | |
2258 | * we want! | |
2259 | */ | |
2260 | if (!(op->flags & FTRACE_OPS_FL_MODIFYING) && | |
2261 | hash_contains_ip(ip, op->func_hash)) | |
2262 | return op; | |
79922b80 SRRH |
2263 | |
2264 | } while_for_each_ftrace_op(op); | |
2265 | ||
2266 | return NULL; | |
2267 | } | |
2268 | ||
2269 | static struct ftrace_ops * | |
2270 | ftrace_find_tramp_ops_new(struct dyn_ftrace *rec) | |
2271 | { | |
2272 | struct ftrace_ops *op; | |
fef5aeee | 2273 | unsigned long ip = rec->ip; |
79922b80 SRRH |
2274 | |
2275 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
2276 | /* pass rec in as regs to have non-NULL val */ | |
fef5aeee | 2277 | if (hash_contains_ip(ip, op->func_hash)) |
79922b80 SRRH |
2278 | return op; |
2279 | } while_for_each_ftrace_op(op); | |
2280 | ||
2281 | return NULL; | |
2282 | } | |
2283 | ||
7413af1f SRRH |
2284 | /** |
2285 | * ftrace_get_addr_new - Get the call address to set to | |
2286 | * @rec: The ftrace record descriptor | |
2287 | * | |
2288 | * If the record has the FTRACE_FL_REGS set, that means that it | |
2289 | * wants to convert to a callback that saves all regs. If FTRACE_FL_REGS | |
2290 | * is not not set, then it wants to convert to the normal callback. | |
2291 | * | |
2292 | * Returns the address of the trampoline to set to | |
2293 | */ | |
2294 | unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec) | |
2295 | { | |
79922b80 SRRH |
2296 | struct ftrace_ops *ops; |
2297 | ||
2298 | /* Trampolines take precedence over regs */ | |
2299 | if (rec->flags & FTRACE_FL_TRAMP) { | |
2300 | ops = ftrace_find_tramp_ops_new(rec); | |
2301 | if (FTRACE_WARN_ON(!ops || !ops->trampoline)) { | |
bce0b6c5 SRRH |
2302 | pr_warn("Bad trampoline accounting at: %p (%pS) (%lx)\n", |
2303 | (void *)rec->ip, (void *)rec->ip, rec->flags); | |
79922b80 SRRH |
2304 | /* Ftrace is shutting down, return anything */ |
2305 | return (unsigned long)FTRACE_ADDR; | |
2306 | } | |
2307 | return ops->trampoline; | |
2308 | } | |
2309 | ||
7413af1f SRRH |
2310 | if (rec->flags & FTRACE_FL_REGS) |
2311 | return (unsigned long)FTRACE_REGS_ADDR; | |
2312 | else | |
2313 | return (unsigned long)FTRACE_ADDR; | |
2314 | } | |
2315 | ||
2316 | /** | |
2317 | * ftrace_get_addr_curr - Get the call address that is already there | |
2318 | * @rec: The ftrace record descriptor | |
2319 | * | |
2320 | * The FTRACE_FL_REGS_EN is set when the record already points to | |
2321 | * a function that saves all the regs. Basically the '_EN' version | |
2322 | * represents the current state of the function. | |
2323 | * | |
2324 | * Returns the address of the trampoline that is currently being called | |
2325 | */ | |
2326 | unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec) | |
2327 | { | |
79922b80 SRRH |
2328 | struct ftrace_ops *ops; |
2329 | ||
2330 | /* Trampolines take precedence over regs */ | |
2331 | if (rec->flags & FTRACE_FL_TRAMP_EN) { | |
2332 | ops = ftrace_find_tramp_ops_curr(rec); | |
2333 | if (FTRACE_WARN_ON(!ops)) { | |
a395d6a7 JP |
2334 | pr_warn("Bad trampoline accounting at: %p (%pS)\n", |
2335 | (void *)rec->ip, (void *)rec->ip); | |
79922b80 SRRH |
2336 | /* Ftrace is shutting down, return anything */ |
2337 | return (unsigned long)FTRACE_ADDR; | |
2338 | } | |
2339 | return ops->trampoline; | |
2340 | } | |
2341 | ||
7413af1f SRRH |
2342 | if (rec->flags & FTRACE_FL_REGS_EN) |
2343 | return (unsigned long)FTRACE_REGS_ADDR; | |
2344 | else | |
2345 | return (unsigned long)FTRACE_ADDR; | |
2346 | } | |
2347 | ||
c88fd863 SR |
2348 | static int |
2349 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) | |
2350 | { | |
08f6fba5 | 2351 | unsigned long ftrace_old_addr; |
c88fd863 SR |
2352 | unsigned long ftrace_addr; |
2353 | int ret; | |
2354 | ||
7c0868e0 | 2355 | ftrace_addr = ftrace_get_addr_new(rec); |
c88fd863 | 2356 | |
7c0868e0 SRRH |
2357 | /* This needs to be done before we call ftrace_update_record */ |
2358 | ftrace_old_addr = ftrace_get_addr_curr(rec); | |
2359 | ||
2360 | ret = ftrace_update_record(rec, enable); | |
08f6fba5 | 2361 | |
02a392a0 SRRH |
2362 | ftrace_bug_type = FTRACE_BUG_UNKNOWN; |
2363 | ||
c88fd863 SR |
2364 | switch (ret) { |
2365 | case FTRACE_UPDATE_IGNORE: | |
2366 | return 0; | |
2367 | ||
2368 | case FTRACE_UPDATE_MAKE_CALL: | |
02a392a0 | 2369 | ftrace_bug_type = FTRACE_BUG_CALL; |
64fbcd16 | 2370 | return ftrace_make_call(rec, ftrace_addr); |
c88fd863 SR |
2371 | |
2372 | case FTRACE_UPDATE_MAKE_NOP: | |
02a392a0 | 2373 | ftrace_bug_type = FTRACE_BUG_NOP; |
39b5552c | 2374 | return ftrace_make_nop(NULL, rec, ftrace_old_addr); |
08f6fba5 | 2375 | |
08f6fba5 | 2376 | case FTRACE_UPDATE_MODIFY_CALL: |
02a392a0 | 2377 | ftrace_bug_type = FTRACE_BUG_UPDATE; |
08f6fba5 | 2378 | return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr); |
5072c59f SR |
2379 | } |
2380 | ||
c88fd863 | 2381 | return -1; /* unknow ftrace bug */ |
5072c59f SR |
2382 | } |
2383 | ||
e4f5d544 | 2384 | void __weak ftrace_replace_code(int enable) |
3c1720f0 | 2385 | { |
3c1720f0 SR |
2386 | struct dyn_ftrace *rec; |
2387 | struct ftrace_page *pg; | |
6a24a244 | 2388 | int failed; |
3c1720f0 | 2389 | |
45a4a237 SR |
2390 | if (unlikely(ftrace_disabled)) |
2391 | return; | |
2392 | ||
265c831c | 2393 | do_for_each_ftrace_rec(pg, rec) { |
e4f5d544 | 2394 | failed = __ftrace_replace_code(rec, enable); |
fa9d13cf | 2395 | if (failed) { |
4fd3279b | 2396 | ftrace_bug(failed, rec); |
3279ba37 SR |
2397 | /* Stop processing */ |
2398 | return; | |
3c1720f0 | 2399 | } |
265c831c | 2400 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
2401 | } |
2402 | ||
c88fd863 SR |
2403 | struct ftrace_rec_iter { |
2404 | struct ftrace_page *pg; | |
2405 | int index; | |
2406 | }; | |
2407 | ||
2408 | /** | |
2409 | * ftrace_rec_iter_start, start up iterating over traced functions | |
2410 | * | |
2411 | * Returns an iterator handle that is used to iterate over all | |
2412 | * the records that represent address locations where functions | |
2413 | * are traced. | |
2414 | * | |
2415 | * May return NULL if no records are available. | |
2416 | */ | |
2417 | struct ftrace_rec_iter *ftrace_rec_iter_start(void) | |
2418 | { | |
2419 | /* | |
2420 | * We only use a single iterator. | |
2421 | * Protected by the ftrace_lock mutex. | |
2422 | */ | |
2423 | static struct ftrace_rec_iter ftrace_rec_iter; | |
2424 | struct ftrace_rec_iter *iter = &ftrace_rec_iter; | |
2425 | ||
2426 | iter->pg = ftrace_pages_start; | |
2427 | iter->index = 0; | |
2428 | ||
2429 | /* Could have empty pages */ | |
2430 | while (iter->pg && !iter->pg->index) | |
2431 | iter->pg = iter->pg->next; | |
2432 | ||
2433 | if (!iter->pg) | |
2434 | return NULL; | |
2435 | ||
2436 | return iter; | |
2437 | } | |
2438 | ||
2439 | /** | |
2440 | * ftrace_rec_iter_next, get the next record to process. | |
2441 | * @iter: The handle to the iterator. | |
2442 | * | |
2443 | * Returns the next iterator after the given iterator @iter. | |
2444 | */ | |
2445 | struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter) | |
2446 | { | |
2447 | iter->index++; | |
2448 | ||
2449 | if (iter->index >= iter->pg->index) { | |
2450 | iter->pg = iter->pg->next; | |
2451 | iter->index = 0; | |
2452 | ||
2453 | /* Could have empty pages */ | |
2454 | while (iter->pg && !iter->pg->index) | |
2455 | iter->pg = iter->pg->next; | |
2456 | } | |
2457 | ||
2458 | if (!iter->pg) | |
2459 | return NULL; | |
2460 | ||
2461 | return iter; | |
2462 | } | |
2463 | ||
2464 | /** | |
2465 | * ftrace_rec_iter_record, get the record at the iterator location | |
2466 | * @iter: The current iterator location | |
2467 | * | |
2468 | * Returns the record that the current @iter is at. | |
2469 | */ | |
2470 | struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter) | |
2471 | { | |
2472 | return &iter->pg->records[iter->index]; | |
2473 | } | |
2474 | ||
492a7ea5 | 2475 | static int |
31e88909 | 2476 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 | 2477 | { |
593eb8a2 | 2478 | int ret; |
3c1720f0 | 2479 | |
45a4a237 SR |
2480 | if (unlikely(ftrace_disabled)) |
2481 | return 0; | |
2482 | ||
25aac9dc | 2483 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
593eb8a2 | 2484 | if (ret) { |
02a392a0 | 2485 | ftrace_bug_type = FTRACE_BUG_INIT; |
4fd3279b | 2486 | ftrace_bug(ret, rec); |
492a7ea5 | 2487 | return 0; |
37ad5084 | 2488 | } |
492a7ea5 | 2489 | return 1; |
3c1720f0 SR |
2490 | } |
2491 | ||
000ab691 SR |
2492 | /* |
2493 | * archs can override this function if they must do something | |
2494 | * before the modifying code is performed. | |
2495 | */ | |
2496 | int __weak ftrace_arch_code_modify_prepare(void) | |
2497 | { | |
2498 | return 0; | |
2499 | } | |
2500 | ||
2501 | /* | |
2502 | * archs can override this function if they must do something | |
2503 | * after the modifying code is performed. | |
2504 | */ | |
2505 | int __weak ftrace_arch_code_modify_post_process(void) | |
2506 | { | |
2507 | return 0; | |
2508 | } | |
2509 | ||
8ed3e2cf | 2510 | void ftrace_modify_all_code(int command) |
3d083395 | 2511 | { |
59338f75 | 2512 | int update = command & FTRACE_UPDATE_TRACE_FUNC; |
cd21067f | 2513 | int err = 0; |
59338f75 SRRH |
2514 | |
2515 | /* | |
2516 | * If the ftrace_caller calls a ftrace_ops func directly, | |
2517 | * we need to make sure that it only traces functions it | |
2518 | * expects to trace. When doing the switch of functions, | |
2519 | * we need to update to the ftrace_ops_list_func first | |
2520 | * before the transition between old and new calls are set, | |
2521 | * as the ftrace_ops_list_func will check the ops hashes | |
2522 | * to make sure the ops are having the right functions | |
2523 | * traced. | |
2524 | */ | |
cd21067f PM |
2525 | if (update) { |
2526 | err = ftrace_update_ftrace_func(ftrace_ops_list_func); | |
2527 | if (FTRACE_WARN_ON(err)) | |
2528 | return; | |
2529 | } | |
59338f75 | 2530 | |
8ed3e2cf | 2531 | if (command & FTRACE_UPDATE_CALLS) |
d61f82d0 | 2532 | ftrace_replace_code(1); |
8ed3e2cf | 2533 | else if (command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
2534 | ftrace_replace_code(0); |
2535 | ||
405e1d83 SRRH |
2536 | if (update && ftrace_trace_function != ftrace_ops_list_func) { |
2537 | function_trace_op = set_function_trace_op; | |
2538 | smp_wmb(); | |
2539 | /* If irqs are disabled, we are in stop machine */ | |
2540 | if (!irqs_disabled()) | |
2541 | smp_call_function(ftrace_sync_ipi, NULL, 1); | |
cd21067f PM |
2542 | err = ftrace_update_ftrace_func(ftrace_trace_function); |
2543 | if (FTRACE_WARN_ON(err)) | |
2544 | return; | |
405e1d83 | 2545 | } |
d61f82d0 | 2546 | |
8ed3e2cf | 2547 | if (command & FTRACE_START_FUNC_RET) |
cd21067f | 2548 | err = ftrace_enable_ftrace_graph_caller(); |
8ed3e2cf | 2549 | else if (command & FTRACE_STOP_FUNC_RET) |
cd21067f PM |
2550 | err = ftrace_disable_ftrace_graph_caller(); |
2551 | FTRACE_WARN_ON(err); | |
8ed3e2cf SR |
2552 | } |
2553 | ||
2554 | static int __ftrace_modify_code(void *data) | |
2555 | { | |
2556 | int *command = data; | |
2557 | ||
2558 | ftrace_modify_all_code(*command); | |
5a45cfe1 | 2559 | |
d61f82d0 | 2560 | return 0; |
3d083395 SR |
2561 | } |
2562 | ||
c88fd863 SR |
2563 | /** |
2564 | * ftrace_run_stop_machine, go back to the stop machine method | |
2565 | * @command: The command to tell ftrace what to do | |
2566 | * | |
2567 | * If an arch needs to fall back to the stop machine method, the | |
2568 | * it can call this function. | |
2569 | */ | |
2570 | void ftrace_run_stop_machine(int command) | |
2571 | { | |
2572 | stop_machine(__ftrace_modify_code, &command, NULL); | |
2573 | } | |
2574 | ||
2575 | /** | |
2576 | * arch_ftrace_update_code, modify the code to trace or not trace | |
2577 | * @command: The command that needs to be done | |
2578 | * | |
2579 | * Archs can override this function if it does not need to | |
2580 | * run stop_machine() to modify code. | |
2581 | */ | |
2582 | void __weak arch_ftrace_update_code(int command) | |
2583 | { | |
2584 | ftrace_run_stop_machine(command); | |
2585 | } | |
2586 | ||
e309b41d | 2587 | static void ftrace_run_update_code(int command) |
3d083395 | 2588 | { |
000ab691 SR |
2589 | int ret; |
2590 | ||
2591 | ret = ftrace_arch_code_modify_prepare(); | |
2592 | FTRACE_WARN_ON(ret); | |
2593 | if (ret) | |
2594 | return; | |
2595 | ||
c88fd863 SR |
2596 | /* |
2597 | * By default we use stop_machine() to modify the code. | |
2598 | * But archs can do what ever they want as long as it | |
2599 | * is safe. The stop_machine() is the safest, but also | |
2600 | * produces the most overhead. | |
2601 | */ | |
2602 | arch_ftrace_update_code(command); | |
2603 | ||
000ab691 SR |
2604 | ret = ftrace_arch_code_modify_post_process(); |
2605 | FTRACE_WARN_ON(ret); | |
3d083395 SR |
2606 | } |
2607 | ||
8252ecf3 | 2608 | static void ftrace_run_modify_code(struct ftrace_ops *ops, int command, |
7485058e | 2609 | struct ftrace_ops_hash *old_hash) |
e1effa01 SRRH |
2610 | { |
2611 | ops->flags |= FTRACE_OPS_FL_MODIFYING; | |
7485058e SRRH |
2612 | ops->old_hash.filter_hash = old_hash->filter_hash; |
2613 | ops->old_hash.notrace_hash = old_hash->notrace_hash; | |
e1effa01 | 2614 | ftrace_run_update_code(command); |
8252ecf3 | 2615 | ops->old_hash.filter_hash = NULL; |
7485058e | 2616 | ops->old_hash.notrace_hash = NULL; |
e1effa01 SRRH |
2617 | ops->flags &= ~FTRACE_OPS_FL_MODIFYING; |
2618 | } | |
2619 | ||
d61f82d0 | 2620 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 2621 | static int ftrace_start_up; |
df4fc315 | 2622 | |
12cce594 SRRH |
2623 | void __weak arch_ftrace_trampoline_free(struct ftrace_ops *ops) |
2624 | { | |
2625 | } | |
2626 | ||
ba27f2bc | 2627 | static void per_cpu_ops_free(struct ftrace_ops *ops) |
db0fbadc JS |
2628 | { |
2629 | free_percpu(ops->disabled); | |
2630 | } | |
2631 | ||
df4fc315 SR |
2632 | static void ftrace_startup_enable(int command) |
2633 | { | |
2634 | if (saved_ftrace_func != ftrace_trace_function) { | |
2635 | saved_ftrace_func = ftrace_trace_function; | |
2636 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2637 | } | |
2638 | ||
2639 | if (!command || !ftrace_enabled) | |
2640 | return; | |
2641 | ||
2642 | ftrace_run_update_code(command); | |
2643 | } | |
d61f82d0 | 2644 | |
e1effa01 SRRH |
2645 | static void ftrace_startup_all(int command) |
2646 | { | |
2647 | update_all_ops = true; | |
2648 | ftrace_startup_enable(command); | |
2649 | update_all_ops = false; | |
2650 | } | |
2651 | ||
a1cd6173 | 2652 | static int ftrace_startup(struct ftrace_ops *ops, int command) |
3d083395 | 2653 | { |
8a56d776 | 2654 | int ret; |
b848914c | 2655 | |
4eebcc81 | 2656 | if (unlikely(ftrace_disabled)) |
a1cd6173 | 2657 | return -ENODEV; |
4eebcc81 | 2658 | |
8a56d776 SRRH |
2659 | ret = __register_ftrace_function(ops); |
2660 | if (ret) | |
2661 | return ret; | |
2662 | ||
60a7ecf4 | 2663 | ftrace_start_up++; |
d61f82d0 | 2664 | |
e1effa01 SRRH |
2665 | /* |
2666 | * Note that ftrace probes uses this to start up | |
2667 | * and modify functions it will probe. But we still | |
2668 | * set the ADDING flag for modification, as probes | |
2669 | * do not have trampolines. If they add them in the | |
2670 | * future, then the probes will need to distinguish | |
2671 | * between adding and updating probes. | |
2672 | */ | |
2673 | ops->flags |= FTRACE_OPS_FL_ENABLED | FTRACE_OPS_FL_ADDING; | |
66209a5b | 2674 | |
f8b8be8a MH |
2675 | ret = ftrace_hash_ipmodify_enable(ops); |
2676 | if (ret < 0) { | |
2677 | /* Rollback registration process */ | |
2678 | __unregister_ftrace_function(ops); | |
2679 | ftrace_start_up--; | |
2680 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; | |
2681 | return ret; | |
2682 | } | |
2683 | ||
7f50d06b JO |
2684 | if (ftrace_hash_rec_enable(ops, 1)) |
2685 | command |= FTRACE_UPDATE_CALLS; | |
ed926f9b | 2686 | |
df4fc315 | 2687 | ftrace_startup_enable(command); |
a1cd6173 | 2688 | |
e1effa01 SRRH |
2689 | ops->flags &= ~FTRACE_OPS_FL_ADDING; |
2690 | ||
a1cd6173 | 2691 | return 0; |
3d083395 SR |
2692 | } |
2693 | ||
8a56d776 | 2694 | static int ftrace_shutdown(struct ftrace_ops *ops, int command) |
3d083395 | 2695 | { |
8a56d776 | 2696 | int ret; |
b848914c | 2697 | |
4eebcc81 | 2698 | if (unlikely(ftrace_disabled)) |
8a56d776 SRRH |
2699 | return -ENODEV; |
2700 | ||
2701 | ret = __unregister_ftrace_function(ops); | |
2702 | if (ret) | |
2703 | return ret; | |
4eebcc81 | 2704 | |
60a7ecf4 | 2705 | ftrace_start_up--; |
9ea1a153 FW |
2706 | /* |
2707 | * Just warn in case of unbalance, no need to kill ftrace, it's not | |
2708 | * critical but the ftrace_call callers may be never nopped again after | |
2709 | * further ftrace uses. | |
2710 | */ | |
2711 | WARN_ON_ONCE(ftrace_start_up < 0); | |
2712 | ||
f8b8be8a MH |
2713 | /* Disabling ipmodify never fails */ |
2714 | ftrace_hash_ipmodify_disable(ops); | |
ed926f9b | 2715 | |
7f50d06b JO |
2716 | if (ftrace_hash_rec_disable(ops, 1)) |
2717 | command |= FTRACE_UPDATE_CALLS; | |
b848914c | 2718 | |
7f50d06b | 2719 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; |
3d083395 | 2720 | |
d61f82d0 SR |
2721 | if (saved_ftrace_func != ftrace_trace_function) { |
2722 | saved_ftrace_func = ftrace_trace_function; | |
2723 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2724 | } | |
3d083395 | 2725 | |
a4c35ed2 SRRH |
2726 | if (!command || !ftrace_enabled) { |
2727 | /* | |
ba27f2bc | 2728 | * If these are per_cpu ops, they still need their |
a4c35ed2 SRRH |
2729 | * per_cpu field freed. Since, function tracing is |
2730 | * not currently active, we can just free them | |
2731 | * without synchronizing all CPUs. | |
2732 | */ | |
ba27f2bc SRRH |
2733 | if (ops->flags & FTRACE_OPS_FL_PER_CPU) |
2734 | per_cpu_ops_free(ops); | |
8a56d776 | 2735 | return 0; |
a4c35ed2 | 2736 | } |
d61f82d0 | 2737 | |
79922b80 SRRH |
2738 | /* |
2739 | * If the ops uses a trampoline, then it needs to be | |
2740 | * tested first on update. | |
2741 | */ | |
e1effa01 | 2742 | ops->flags |= FTRACE_OPS_FL_REMOVING; |
79922b80 SRRH |
2743 | removed_ops = ops; |
2744 | ||
fef5aeee SRRH |
2745 | /* The trampoline logic checks the old hashes */ |
2746 | ops->old_hash.filter_hash = ops->func_hash->filter_hash; | |
2747 | ops->old_hash.notrace_hash = ops->func_hash->notrace_hash; | |
2748 | ||
d61f82d0 | 2749 | ftrace_run_update_code(command); |
a4c35ed2 | 2750 | |
84bde62c SRRH |
2751 | /* |
2752 | * If there's no more ops registered with ftrace, run a | |
2753 | * sanity check to make sure all rec flags are cleared. | |
2754 | */ | |
2755 | if (ftrace_ops_list == &ftrace_list_end) { | |
2756 | struct ftrace_page *pg; | |
2757 | struct dyn_ftrace *rec; | |
2758 | ||
2759 | do_for_each_ftrace_rec(pg, rec) { | |
2760 | if (FTRACE_WARN_ON_ONCE(rec->flags)) | |
2761 | pr_warn(" %pS flags:%lx\n", | |
2762 | (void *)rec->ip, rec->flags); | |
2763 | } while_for_each_ftrace_rec(); | |
2764 | } | |
2765 | ||
fef5aeee SRRH |
2766 | ops->old_hash.filter_hash = NULL; |
2767 | ops->old_hash.notrace_hash = NULL; | |
2768 | ||
2769 | removed_ops = NULL; | |
e1effa01 | 2770 | ops->flags &= ~FTRACE_OPS_FL_REMOVING; |
79922b80 | 2771 | |
a4c35ed2 SRRH |
2772 | /* |
2773 | * Dynamic ops may be freed, we must make sure that all | |
2774 | * callers are done before leaving this function. | |
ba27f2bc | 2775 | * The same goes for freeing the per_cpu data of the per_cpu |
a4c35ed2 SRRH |
2776 | * ops. |
2777 | * | |
2778 | * Again, normal synchronize_sched() is not good enough. | |
2779 | * We need to do a hard force of sched synchronization. | |
2780 | * This is because we use preempt_disable() to do RCU, but | |
2781 | * the function tracers can be called where RCU is not watching | |
2782 | * (like before user_exit()). We can not rely on the RCU | |
2783 | * infrastructure to do the synchronization, thus we must do it | |
2784 | * ourselves. | |
2785 | */ | |
ba27f2bc | 2786 | if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_PER_CPU)) { |
a4c35ed2 SRRH |
2787 | schedule_on_each_cpu(ftrace_sync); |
2788 | ||
12cce594 SRRH |
2789 | arch_ftrace_trampoline_free(ops); |
2790 | ||
ba27f2bc SRRH |
2791 | if (ops->flags & FTRACE_OPS_FL_PER_CPU) |
2792 | per_cpu_ops_free(ops); | |
a4c35ed2 SRRH |
2793 | } |
2794 | ||
8a56d776 | 2795 | return 0; |
3d083395 SR |
2796 | } |
2797 | ||
e309b41d | 2798 | static void ftrace_startup_sysctl(void) |
b0fc494f | 2799 | { |
1619dc3f PA |
2800 | int command; |
2801 | ||
4eebcc81 SR |
2802 | if (unlikely(ftrace_disabled)) |
2803 | return; | |
2804 | ||
d61f82d0 SR |
2805 | /* Force update next time */ |
2806 | saved_ftrace_func = NULL; | |
60a7ecf4 | 2807 | /* ftrace_start_up is true if we want ftrace running */ |
1619dc3f PA |
2808 | if (ftrace_start_up) { |
2809 | command = FTRACE_UPDATE_CALLS; | |
2810 | if (ftrace_graph_active) | |
2811 | command |= FTRACE_START_FUNC_RET; | |
524a3868 | 2812 | ftrace_startup_enable(command); |
1619dc3f | 2813 | } |
b0fc494f SR |
2814 | } |
2815 | ||
e309b41d | 2816 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 2817 | { |
1619dc3f PA |
2818 | int command; |
2819 | ||
4eebcc81 SR |
2820 | if (unlikely(ftrace_disabled)) |
2821 | return; | |
2822 | ||
60a7ecf4 | 2823 | /* ftrace_start_up is true if ftrace is running */ |
1619dc3f PA |
2824 | if (ftrace_start_up) { |
2825 | command = FTRACE_DISABLE_CALLS; | |
2826 | if (ftrace_graph_active) | |
2827 | command |= FTRACE_STOP_FUNC_RET; | |
2828 | ftrace_run_update_code(command); | |
2829 | } | |
b0fc494f SR |
2830 | } |
2831 | ||
3d083395 | 2832 | static cycle_t ftrace_update_time; |
3d083395 SR |
2833 | unsigned long ftrace_update_tot_cnt; |
2834 | ||
8c4f3c3f | 2835 | static inline int ops_traces_mod(struct ftrace_ops *ops) |
f7bc8b61 | 2836 | { |
8c4f3c3f SRRH |
2837 | /* |
2838 | * Filter_hash being empty will default to trace module. | |
2839 | * But notrace hash requires a test of individual module functions. | |
2840 | */ | |
33b7f99c SRRH |
2841 | return ftrace_hash_empty(ops->func_hash->filter_hash) && |
2842 | ftrace_hash_empty(ops->func_hash->notrace_hash); | |
8c4f3c3f SRRH |
2843 | } |
2844 | ||
2845 | /* | |
2846 | * Check if the current ops references the record. | |
2847 | * | |
2848 | * If the ops traces all functions, then it was already accounted for. | |
2849 | * If the ops does not trace the current record function, skip it. | |
2850 | * If the ops ignores the function via notrace filter, skip it. | |
2851 | */ | |
2852 | static inline bool | |
2853 | ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec) | |
2854 | { | |
2855 | /* If ops isn't enabled, ignore it */ | |
2856 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
2857 | return 0; | |
2858 | ||
b7ffffbb | 2859 | /* If ops traces all then it includes this function */ |
8c4f3c3f | 2860 | if (ops_traces_mod(ops)) |
b7ffffbb | 2861 | return 1; |
8c4f3c3f SRRH |
2862 | |
2863 | /* The function must be in the filter */ | |
33b7f99c SRRH |
2864 | if (!ftrace_hash_empty(ops->func_hash->filter_hash) && |
2865 | !ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip)) | |
8c4f3c3f | 2866 | return 0; |
f7bc8b61 | 2867 | |
8c4f3c3f | 2868 | /* If in notrace hash, we ignore it too */ |
33b7f99c | 2869 | if (ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip)) |
8c4f3c3f SRRH |
2870 | return 0; |
2871 | ||
2872 | return 1; | |
2873 | } | |
2874 | ||
1dc43cf0 | 2875 | static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs) |
3d083395 | 2876 | { |
85ae32ae | 2877 | struct ftrace_page *pg; |
e94142a6 | 2878 | struct dyn_ftrace *p; |
f22f9a89 | 2879 | cycle_t start, stop; |
1dc43cf0 | 2880 | unsigned long update_cnt = 0; |
b7ffffbb | 2881 | unsigned long rec_flags = 0; |
85ae32ae | 2882 | int i; |
f7bc8b61 | 2883 | |
b7ffffbb SRRH |
2884 | start = ftrace_now(raw_smp_processor_id()); |
2885 | ||
f7bc8b61 | 2886 | /* |
b7ffffbb SRRH |
2887 | * When a module is loaded, this function is called to convert |
2888 | * the calls to mcount in its text to nops, and also to create | |
2889 | * an entry in the ftrace data. Now, if ftrace is activated | |
2890 | * after this call, but before the module sets its text to | |
2891 | * read-only, the modification of enabling ftrace can fail if | |
2892 | * the read-only is done while ftrace is converting the calls. | |
2893 | * To prevent this, the module's records are set as disabled | |
2894 | * and will be enabled after the call to set the module's text | |
2895 | * to read-only. | |
f7bc8b61 | 2896 | */ |
b7ffffbb SRRH |
2897 | if (mod) |
2898 | rec_flags |= FTRACE_FL_DISABLED; | |
3d083395 | 2899 | |
1dc43cf0 | 2900 | for (pg = new_pgs; pg; pg = pg->next) { |
3d083395 | 2901 | |
85ae32ae | 2902 | for (i = 0; i < pg->index; i++) { |
8c4f3c3f | 2903 | |
85ae32ae SR |
2904 | /* If something went wrong, bail without enabling anything */ |
2905 | if (unlikely(ftrace_disabled)) | |
2906 | return -1; | |
f22f9a89 | 2907 | |
85ae32ae | 2908 | p = &pg->records[i]; |
b7ffffbb | 2909 | p->flags = rec_flags; |
f22f9a89 | 2910 | |
85ae32ae SR |
2911 | /* |
2912 | * Do the initial record conversion from mcount jump | |
2913 | * to the NOP instructions. | |
2914 | */ | |
2915 | if (!ftrace_code_disable(mod, p)) | |
2916 | break; | |
5cb084bb | 2917 | |
1dc43cf0 | 2918 | update_cnt++; |
5cb084bb | 2919 | } |
3d083395 SR |
2920 | } |
2921 | ||
750ed1a4 | 2922 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 | 2923 | ftrace_update_time = stop - start; |
1dc43cf0 | 2924 | ftrace_update_tot_cnt += update_cnt; |
3d083395 | 2925 | |
16444a8a ACM |
2926 | return 0; |
2927 | } | |
2928 | ||
a7900875 | 2929 | static int ftrace_allocate_records(struct ftrace_page *pg, int count) |
3c1720f0 | 2930 | { |
a7900875 | 2931 | int order; |
3c1720f0 | 2932 | int cnt; |
3c1720f0 | 2933 | |
a7900875 SR |
2934 | if (WARN_ON(!count)) |
2935 | return -EINVAL; | |
2936 | ||
2937 | order = get_count_order(DIV_ROUND_UP(count, ENTRIES_PER_PAGE)); | |
3c1720f0 SR |
2938 | |
2939 | /* | |
a7900875 SR |
2940 | * We want to fill as much as possible. No more than a page |
2941 | * may be empty. | |
3c1720f0 | 2942 | */ |
a7900875 SR |
2943 | while ((PAGE_SIZE << order) / ENTRY_SIZE >= count + ENTRIES_PER_PAGE) |
2944 | order--; | |
3c1720f0 | 2945 | |
a7900875 SR |
2946 | again: |
2947 | pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); | |
3c1720f0 | 2948 | |
a7900875 SR |
2949 | if (!pg->records) { |
2950 | /* if we can't allocate this size, try something smaller */ | |
2951 | if (!order) | |
2952 | return -ENOMEM; | |
2953 | order >>= 1; | |
2954 | goto again; | |
2955 | } | |
3c1720f0 | 2956 | |
a7900875 SR |
2957 | cnt = (PAGE_SIZE << order) / ENTRY_SIZE; |
2958 | pg->size = cnt; | |
3c1720f0 | 2959 | |
a7900875 SR |
2960 | if (cnt > count) |
2961 | cnt = count; | |
2962 | ||
2963 | return cnt; | |
2964 | } | |
2965 | ||
2966 | static struct ftrace_page * | |
2967 | ftrace_allocate_pages(unsigned long num_to_init) | |
2968 | { | |
2969 | struct ftrace_page *start_pg; | |
2970 | struct ftrace_page *pg; | |
2971 | int order; | |
2972 | int cnt; | |
2973 | ||
2974 | if (!num_to_init) | |
2975 | return 0; | |
2976 | ||
2977 | start_pg = pg = kzalloc(sizeof(*pg), GFP_KERNEL); | |
2978 | if (!pg) | |
2979 | return NULL; | |
2980 | ||
2981 | /* | |
2982 | * Try to allocate as much as possible in one continues | |
2983 | * location that fills in all of the space. We want to | |
2984 | * waste as little space as possible. | |
2985 | */ | |
2986 | for (;;) { | |
2987 | cnt = ftrace_allocate_records(pg, num_to_init); | |
2988 | if (cnt < 0) | |
2989 | goto free_pages; | |
2990 | ||
2991 | num_to_init -= cnt; | |
2992 | if (!num_to_init) | |
3c1720f0 SR |
2993 | break; |
2994 | ||
a7900875 SR |
2995 | pg->next = kzalloc(sizeof(*pg), GFP_KERNEL); |
2996 | if (!pg->next) | |
2997 | goto free_pages; | |
2998 | ||
3c1720f0 SR |
2999 | pg = pg->next; |
3000 | } | |
3001 | ||
a7900875 SR |
3002 | return start_pg; |
3003 | ||
3004 | free_pages: | |
1f61be00 NK |
3005 | pg = start_pg; |
3006 | while (pg) { | |
a7900875 SR |
3007 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); |
3008 | free_pages((unsigned long)pg->records, order); | |
3009 | start_pg = pg->next; | |
3010 | kfree(pg); | |
3011 | pg = start_pg; | |
3012 | } | |
3013 | pr_info("ftrace: FAILED to allocate memory for functions\n"); | |
3014 | return NULL; | |
3015 | } | |
3016 | ||
5072c59f SR |
3017 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ |
3018 | ||
3019 | struct ftrace_iterator { | |
98c4fd04 | 3020 | loff_t pos; |
4aeb6967 SR |
3021 | loff_t func_pos; |
3022 | struct ftrace_page *pg; | |
3023 | struct dyn_ftrace *func; | |
3024 | struct ftrace_func_probe *probe; | |
3025 | struct trace_parser parser; | |
1cf41dd7 | 3026 | struct ftrace_hash *hash; |
33dc9b12 | 3027 | struct ftrace_ops *ops; |
4aeb6967 SR |
3028 | int hidx; |
3029 | int idx; | |
3030 | unsigned flags; | |
5072c59f SR |
3031 | }; |
3032 | ||
8fc0c701 | 3033 | static void * |
4aeb6967 | 3034 | t_hash_next(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
3035 | { |
3036 | struct ftrace_iterator *iter = m->private; | |
4aeb6967 | 3037 | struct hlist_node *hnd = NULL; |
8fc0c701 SR |
3038 | struct hlist_head *hhd; |
3039 | ||
8fc0c701 | 3040 | (*pos)++; |
98c4fd04 | 3041 | iter->pos = *pos; |
8fc0c701 | 3042 | |
4aeb6967 SR |
3043 | if (iter->probe) |
3044 | hnd = &iter->probe->node; | |
8fc0c701 SR |
3045 | retry: |
3046 | if (iter->hidx >= FTRACE_FUNC_HASHSIZE) | |
3047 | return NULL; | |
3048 | ||
3049 | hhd = &ftrace_func_hash[iter->hidx]; | |
3050 | ||
3051 | if (hlist_empty(hhd)) { | |
3052 | iter->hidx++; | |
3053 | hnd = NULL; | |
3054 | goto retry; | |
3055 | } | |
3056 | ||
3057 | if (!hnd) | |
3058 | hnd = hhd->first; | |
3059 | else { | |
3060 | hnd = hnd->next; | |
3061 | if (!hnd) { | |
3062 | iter->hidx++; | |
3063 | goto retry; | |
3064 | } | |
3065 | } | |
3066 | ||
4aeb6967 SR |
3067 | if (WARN_ON_ONCE(!hnd)) |
3068 | return NULL; | |
3069 | ||
3070 | iter->probe = hlist_entry(hnd, struct ftrace_func_probe, node); | |
3071 | ||
3072 | return iter; | |
8fc0c701 SR |
3073 | } |
3074 | ||
3075 | static void *t_hash_start(struct seq_file *m, loff_t *pos) | |
3076 | { | |
3077 | struct ftrace_iterator *iter = m->private; | |
3078 | void *p = NULL; | |
d82d6244 LZ |
3079 | loff_t l; |
3080 | ||
69a3083c SR |
3081 | if (!(iter->flags & FTRACE_ITER_DO_HASH)) |
3082 | return NULL; | |
3083 | ||
2bccfffd SR |
3084 | if (iter->func_pos > *pos) |
3085 | return NULL; | |
8fc0c701 | 3086 | |
d82d6244 | 3087 | iter->hidx = 0; |
2bccfffd | 3088 | for (l = 0; l <= (*pos - iter->func_pos); ) { |
4aeb6967 | 3089 | p = t_hash_next(m, &l); |
d82d6244 LZ |
3090 | if (!p) |
3091 | break; | |
3092 | } | |
4aeb6967 SR |
3093 | if (!p) |
3094 | return NULL; | |
3095 | ||
98c4fd04 SR |
3096 | /* Only set this if we have an item */ |
3097 | iter->flags |= FTRACE_ITER_HASH; | |
3098 | ||
4aeb6967 | 3099 | return iter; |
8fc0c701 SR |
3100 | } |
3101 | ||
4aeb6967 SR |
3102 | static int |
3103 | t_hash_show(struct seq_file *m, struct ftrace_iterator *iter) | |
8fc0c701 | 3104 | { |
b6887d79 | 3105 | struct ftrace_func_probe *rec; |
8fc0c701 | 3106 | |
4aeb6967 SR |
3107 | rec = iter->probe; |
3108 | if (WARN_ON_ONCE(!rec)) | |
3109 | return -EIO; | |
8fc0c701 | 3110 | |
809dcf29 SR |
3111 | if (rec->ops->print) |
3112 | return rec->ops->print(m, rec->ip, rec->ops, rec->data); | |
3113 | ||
b375a11a | 3114 | seq_printf(m, "%ps:%ps", (void *)rec->ip, (void *)rec->ops->func); |
8fc0c701 SR |
3115 | |
3116 | if (rec->data) | |
3117 | seq_printf(m, ":%p", rec->data); | |
3118 | seq_putc(m, '\n'); | |
3119 | ||
3120 | return 0; | |
3121 | } | |
3122 | ||
e309b41d | 3123 | static void * |
5072c59f SR |
3124 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3125 | { | |
3126 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 3127 | struct ftrace_ops *ops = iter->ops; |
5072c59f SR |
3128 | struct dyn_ftrace *rec = NULL; |
3129 | ||
45a4a237 SR |
3130 | if (unlikely(ftrace_disabled)) |
3131 | return NULL; | |
3132 | ||
8fc0c701 | 3133 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 3134 | return t_hash_next(m, pos); |
8fc0c701 | 3135 | |
5072c59f | 3136 | (*pos)++; |
1106b699 | 3137 | iter->pos = iter->func_pos = *pos; |
5072c59f | 3138 | |
0c75a3ed | 3139 | if (iter->flags & FTRACE_ITER_PRINTALL) |
57c072c7 | 3140 | return t_hash_start(m, pos); |
0c75a3ed | 3141 | |
5072c59f SR |
3142 | retry: |
3143 | if (iter->idx >= iter->pg->index) { | |
3144 | if (iter->pg->next) { | |
3145 | iter->pg = iter->pg->next; | |
3146 | iter->idx = 0; | |
3147 | goto retry; | |
3148 | } | |
3149 | } else { | |
3150 | rec = &iter->pg->records[iter->idx++]; | |
32082309 | 3151 | if (((iter->flags & FTRACE_ITER_FILTER) && |
33b7f99c | 3152 | !(ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip))) || |
0183fb1c | 3153 | |
41c52c0d | 3154 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
33b7f99c | 3155 | !ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip)) || |
647bcd03 SR |
3156 | |
3157 | ((iter->flags & FTRACE_ITER_ENABLED) && | |
23ea9c4d | 3158 | !(rec->flags & FTRACE_FL_ENABLED))) { |
647bcd03 | 3159 | |
5072c59f SR |
3160 | rec = NULL; |
3161 | goto retry; | |
3162 | } | |
3163 | } | |
3164 | ||
4aeb6967 | 3165 | if (!rec) |
57c072c7 | 3166 | return t_hash_start(m, pos); |
4aeb6967 SR |
3167 | |
3168 | iter->func = rec; | |
3169 | ||
3170 | return iter; | |
5072c59f SR |
3171 | } |
3172 | ||
98c4fd04 SR |
3173 | static void reset_iter_read(struct ftrace_iterator *iter) |
3174 | { | |
3175 | iter->pos = 0; | |
3176 | iter->func_pos = 0; | |
70f77b3f | 3177 | iter->flags &= ~(FTRACE_ITER_PRINTALL | FTRACE_ITER_HASH); |
5072c59f SR |
3178 | } |
3179 | ||
3180 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3181 | { | |
3182 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 3183 | struct ftrace_ops *ops = iter->ops; |
5072c59f | 3184 | void *p = NULL; |
694ce0a5 | 3185 | loff_t l; |
5072c59f | 3186 | |
8fc0c701 | 3187 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
3188 | |
3189 | if (unlikely(ftrace_disabled)) | |
3190 | return NULL; | |
3191 | ||
98c4fd04 SR |
3192 | /* |
3193 | * If an lseek was done, then reset and start from beginning. | |
3194 | */ | |
3195 | if (*pos < iter->pos) | |
3196 | reset_iter_read(iter); | |
3197 | ||
0c75a3ed SR |
3198 | /* |
3199 | * For set_ftrace_filter reading, if we have the filter | |
3200 | * off, we can short cut and just print out that all | |
3201 | * functions are enabled. | |
3202 | */ | |
8c006cf7 | 3203 | if ((iter->flags & FTRACE_ITER_FILTER && |
33b7f99c | 3204 | ftrace_hash_empty(ops->func_hash->filter_hash)) || |
8c006cf7 | 3205 | (iter->flags & FTRACE_ITER_NOTRACE && |
33b7f99c | 3206 | ftrace_hash_empty(ops->func_hash->notrace_hash))) { |
0c75a3ed | 3207 | if (*pos > 0) |
8fc0c701 | 3208 | return t_hash_start(m, pos); |
0c75a3ed | 3209 | iter->flags |= FTRACE_ITER_PRINTALL; |
df091625 CW |
3210 | /* reset in case of seek/pread */ |
3211 | iter->flags &= ~FTRACE_ITER_HASH; | |
0c75a3ed SR |
3212 | return iter; |
3213 | } | |
3214 | ||
8fc0c701 SR |
3215 | if (iter->flags & FTRACE_ITER_HASH) |
3216 | return t_hash_start(m, pos); | |
3217 | ||
98c4fd04 SR |
3218 | /* |
3219 | * Unfortunately, we need to restart at ftrace_pages_start | |
3220 | * every time we let go of the ftrace_mutex. This is because | |
3221 | * those pointers can change without the lock. | |
3222 | */ | |
694ce0a5 LZ |
3223 | iter->pg = ftrace_pages_start; |
3224 | iter->idx = 0; | |
3225 | for (l = 0; l <= *pos; ) { | |
3226 | p = t_next(m, p, &l); | |
3227 | if (!p) | |
3228 | break; | |
50cdaf08 | 3229 | } |
5821e1b7 | 3230 | |
69a3083c SR |
3231 | if (!p) |
3232 | return t_hash_start(m, pos); | |
4aeb6967 SR |
3233 | |
3234 | return iter; | |
5072c59f SR |
3235 | } |
3236 | ||
3237 | static void t_stop(struct seq_file *m, void *p) | |
3238 | { | |
8fc0c701 | 3239 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
3240 | } |
3241 | ||
15d5b02c SRRH |
3242 | void * __weak |
3243 | arch_ftrace_trampoline_func(struct ftrace_ops *ops, struct dyn_ftrace *rec) | |
3244 | { | |
3245 | return NULL; | |
3246 | } | |
3247 | ||
3248 | static void add_trampoline_func(struct seq_file *m, struct ftrace_ops *ops, | |
3249 | struct dyn_ftrace *rec) | |
3250 | { | |
3251 | void *ptr; | |
3252 | ||
3253 | ptr = arch_ftrace_trampoline_func(ops, rec); | |
3254 | if (ptr) | |
3255 | seq_printf(m, " ->%pS", ptr); | |
3256 | } | |
3257 | ||
5072c59f SR |
3258 | static int t_show(struct seq_file *m, void *v) |
3259 | { | |
0c75a3ed | 3260 | struct ftrace_iterator *iter = m->private; |
4aeb6967 | 3261 | struct dyn_ftrace *rec; |
5072c59f | 3262 | |
8fc0c701 | 3263 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 3264 | return t_hash_show(m, iter); |
8fc0c701 | 3265 | |
0c75a3ed | 3266 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
8c006cf7 | 3267 | if (iter->flags & FTRACE_ITER_NOTRACE) |
fa6f0cc7 | 3268 | seq_puts(m, "#### no functions disabled ####\n"); |
8c006cf7 | 3269 | else |
fa6f0cc7 | 3270 | seq_puts(m, "#### all functions enabled ####\n"); |
0c75a3ed SR |
3271 | return 0; |
3272 | } | |
3273 | ||
4aeb6967 SR |
3274 | rec = iter->func; |
3275 | ||
5072c59f SR |
3276 | if (!rec) |
3277 | return 0; | |
3278 | ||
647bcd03 | 3279 | seq_printf(m, "%ps", (void *)rec->ip); |
9674b2fa | 3280 | if (iter->flags & FTRACE_ITER_ENABLED) { |
030f4e1c | 3281 | struct ftrace_ops *ops; |
15d5b02c | 3282 | |
f8b8be8a | 3283 | seq_printf(m, " (%ld)%s%s", |
0376bde1 | 3284 | ftrace_rec_count(rec), |
f8b8be8a MH |
3285 | rec->flags & FTRACE_FL_REGS ? " R" : " ", |
3286 | rec->flags & FTRACE_FL_IPMODIFY ? " I" : " "); | |
9674b2fa | 3287 | if (rec->flags & FTRACE_FL_TRAMP_EN) { |
5fecaa04 | 3288 | ops = ftrace_find_tramp_ops_any(rec); |
39daa7b9 SRRH |
3289 | if (ops) { |
3290 | do { | |
3291 | seq_printf(m, "\ttramp: %pS (%pS)", | |
3292 | (void *)ops->trampoline, | |
3293 | (void *)ops->func); | |
030f4e1c | 3294 | add_trampoline_func(m, ops, rec); |
39daa7b9 SRRH |
3295 | ops = ftrace_find_tramp_ops_next(rec, ops); |
3296 | } while (ops); | |
3297 | } else | |
fa6f0cc7 | 3298 | seq_puts(m, "\ttramp: ERROR!"); |
030f4e1c SRRH |
3299 | } else { |
3300 | add_trampoline_func(m, NULL, rec); | |
9674b2fa SRRH |
3301 | } |
3302 | } | |
3303 | ||
fa6f0cc7 | 3304 | seq_putc(m, '\n'); |
5072c59f SR |
3305 | |
3306 | return 0; | |
3307 | } | |
3308 | ||
88e9d34c | 3309 | static const struct seq_operations show_ftrace_seq_ops = { |
5072c59f SR |
3310 | .start = t_start, |
3311 | .next = t_next, | |
3312 | .stop = t_stop, | |
3313 | .show = t_show, | |
3314 | }; | |
3315 | ||
e309b41d | 3316 | static int |
5072c59f SR |
3317 | ftrace_avail_open(struct inode *inode, struct file *file) |
3318 | { | |
3319 | struct ftrace_iterator *iter; | |
5072c59f | 3320 | |
4eebcc81 SR |
3321 | if (unlikely(ftrace_disabled)) |
3322 | return -ENODEV; | |
3323 | ||
50e18b94 JO |
3324 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
3325 | if (iter) { | |
3326 | iter->pg = ftrace_pages_start; | |
3327 | iter->ops = &global_ops; | |
4bf39a94 | 3328 | } |
5072c59f | 3329 | |
50e18b94 | 3330 | return iter ? 0 : -ENOMEM; |
5072c59f SR |
3331 | } |
3332 | ||
647bcd03 SR |
3333 | static int |
3334 | ftrace_enabled_open(struct inode *inode, struct file *file) | |
3335 | { | |
3336 | struct ftrace_iterator *iter; | |
647bcd03 | 3337 | |
50e18b94 JO |
3338 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
3339 | if (iter) { | |
3340 | iter->pg = ftrace_pages_start; | |
3341 | iter->flags = FTRACE_ITER_ENABLED; | |
3342 | iter->ops = &global_ops; | |
647bcd03 SR |
3343 | } |
3344 | ||
50e18b94 | 3345 | return iter ? 0 : -ENOMEM; |
647bcd03 SR |
3346 | } |
3347 | ||
fc13cb0c SR |
3348 | /** |
3349 | * ftrace_regex_open - initialize function tracer filter files | |
3350 | * @ops: The ftrace_ops that hold the hash filters | |
3351 | * @flag: The type of filter to process | |
3352 | * @inode: The inode, usually passed in to your open routine | |
3353 | * @file: The file, usually passed in to your open routine | |
3354 | * | |
3355 | * ftrace_regex_open() initializes the filter files for the | |
3356 | * @ops. Depending on @flag it may process the filter hash or | |
3357 | * the notrace hash of @ops. With this called from the open | |
3358 | * routine, you can use ftrace_filter_write() for the write | |
3359 | * routine if @flag has FTRACE_ITER_FILTER set, or | |
3360 | * ftrace_notrace_write() if @flag has FTRACE_ITER_NOTRACE set. | |
098c879e | 3361 | * tracing_lseek() should be used as the lseek routine, and |
fc13cb0c SR |
3362 | * release must call ftrace_regex_release(). |
3363 | */ | |
3364 | int | |
f45948e8 | 3365 | ftrace_regex_open(struct ftrace_ops *ops, int flag, |
1cf41dd7 | 3366 | struct inode *inode, struct file *file) |
5072c59f SR |
3367 | { |
3368 | struct ftrace_iterator *iter; | |
f45948e8 | 3369 | struct ftrace_hash *hash; |
5072c59f SR |
3370 | int ret = 0; |
3371 | ||
f04f24fb MH |
3372 | ftrace_ops_init(ops); |
3373 | ||
4eebcc81 SR |
3374 | if (unlikely(ftrace_disabled)) |
3375 | return -ENODEV; | |
3376 | ||
5072c59f SR |
3377 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
3378 | if (!iter) | |
3379 | return -ENOMEM; | |
3380 | ||
689fd8b6 | 3381 | if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) { |
3382 | kfree(iter); | |
3383 | return -ENOMEM; | |
3384 | } | |
3385 | ||
3f2367ba MH |
3386 | iter->ops = ops; |
3387 | iter->flags = flag; | |
3388 | ||
33b7f99c | 3389 | mutex_lock(&ops->func_hash->regex_lock); |
3f2367ba | 3390 | |
f45948e8 | 3391 | if (flag & FTRACE_ITER_NOTRACE) |
33b7f99c | 3392 | hash = ops->func_hash->notrace_hash; |
f45948e8 | 3393 | else |
33b7f99c | 3394 | hash = ops->func_hash->filter_hash; |
f45948e8 | 3395 | |
33dc9b12 | 3396 | if (file->f_mode & FMODE_WRITE) { |
ef2fbe16 NK |
3397 | const int size_bits = FTRACE_HASH_DEFAULT_BITS; |
3398 | ||
3399 | if (file->f_flags & O_TRUNC) | |
3400 | iter->hash = alloc_ftrace_hash(size_bits); | |
3401 | else | |
3402 | iter->hash = alloc_and_copy_ftrace_hash(size_bits, hash); | |
3403 | ||
33dc9b12 SR |
3404 | if (!iter->hash) { |
3405 | trace_parser_put(&iter->parser); | |
3406 | kfree(iter); | |
3f2367ba MH |
3407 | ret = -ENOMEM; |
3408 | goto out_unlock; | |
33dc9b12 SR |
3409 | } |
3410 | } | |
1cf41dd7 | 3411 | |
5072c59f SR |
3412 | if (file->f_mode & FMODE_READ) { |
3413 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
3414 | |
3415 | ret = seq_open(file, &show_ftrace_seq_ops); | |
3416 | if (!ret) { | |
3417 | struct seq_file *m = file->private_data; | |
3418 | m->private = iter; | |
79fe249c | 3419 | } else { |
33dc9b12 SR |
3420 | /* Failed */ |
3421 | free_ftrace_hash(iter->hash); | |
79fe249c | 3422 | trace_parser_put(&iter->parser); |
5072c59f | 3423 | kfree(iter); |
79fe249c | 3424 | } |
5072c59f SR |
3425 | } else |
3426 | file->private_data = iter; | |
3f2367ba MH |
3427 | |
3428 | out_unlock: | |
33b7f99c | 3429 | mutex_unlock(&ops->func_hash->regex_lock); |
5072c59f SR |
3430 | |
3431 | return ret; | |
3432 | } | |
3433 | ||
41c52c0d SR |
3434 | static int |
3435 | ftrace_filter_open(struct inode *inode, struct file *file) | |
3436 | { | |
e3b3e2e8 SRRH |
3437 | struct ftrace_ops *ops = inode->i_private; |
3438 | ||
3439 | return ftrace_regex_open(ops, | |
69a3083c SR |
3440 | FTRACE_ITER_FILTER | FTRACE_ITER_DO_HASH, |
3441 | inode, file); | |
41c52c0d SR |
3442 | } |
3443 | ||
3444 | static int | |
3445 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
3446 | { | |
e3b3e2e8 SRRH |
3447 | struct ftrace_ops *ops = inode->i_private; |
3448 | ||
3449 | return ftrace_regex_open(ops, FTRACE_ITER_NOTRACE, | |
1cf41dd7 | 3450 | inode, file); |
41c52c0d SR |
3451 | } |
3452 | ||
3ba00929 DS |
3453 | /* Type for quick search ftrace basic regexes (globs) from filter_parse_regex */ |
3454 | struct ftrace_glob { | |
3455 | char *search; | |
3456 | unsigned len; | |
3457 | int type; | |
3458 | }; | |
3459 | ||
7132e2d6 TJB |
3460 | /* |
3461 | * If symbols in an architecture don't correspond exactly to the user-visible | |
3462 | * name of what they represent, it is possible to define this function to | |
3463 | * perform the necessary adjustments. | |
3464 | */ | |
3465 | char * __weak arch_ftrace_match_adjust(char *str, const char *search) | |
3466 | { | |
3467 | return str; | |
3468 | } | |
3469 | ||
3ba00929 | 3470 | static int ftrace_match(char *str, struct ftrace_glob *g) |
9f4801e3 | 3471 | { |
9f4801e3 | 3472 | int matched = 0; |
751e9983 | 3473 | int slen; |
9f4801e3 | 3474 | |
7132e2d6 TJB |
3475 | str = arch_ftrace_match_adjust(str, g->search); |
3476 | ||
3ba00929 | 3477 | switch (g->type) { |
9f4801e3 | 3478 | case MATCH_FULL: |
3ba00929 | 3479 | if (strcmp(str, g->search) == 0) |
9f4801e3 SR |
3480 | matched = 1; |
3481 | break; | |
3482 | case MATCH_FRONT_ONLY: | |
3ba00929 | 3483 | if (strncmp(str, g->search, g->len) == 0) |
9f4801e3 SR |
3484 | matched = 1; |
3485 | break; | |
3486 | case MATCH_MIDDLE_ONLY: | |
3ba00929 | 3487 | if (strstr(str, g->search)) |
9f4801e3 SR |
3488 | matched = 1; |
3489 | break; | |
3490 | case MATCH_END_ONLY: | |
751e9983 | 3491 | slen = strlen(str); |
3ba00929 DS |
3492 | if (slen >= g->len && |
3493 | memcmp(str + slen - g->len, g->search, g->len) == 0) | |
9f4801e3 SR |
3494 | matched = 1; |
3495 | break; | |
3496 | } | |
3497 | ||
3498 | return matched; | |
3499 | } | |
3500 | ||
b448c4e3 | 3501 | static int |
f0a3b154 | 3502 | enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int clear_filter) |
996e87be | 3503 | { |
b448c4e3 | 3504 | struct ftrace_func_entry *entry; |
b448c4e3 SR |
3505 | int ret = 0; |
3506 | ||
1cf41dd7 | 3507 | entry = ftrace_lookup_ip(hash, rec->ip); |
f0a3b154 | 3508 | if (clear_filter) { |
1cf41dd7 SR |
3509 | /* Do nothing if it doesn't exist */ |
3510 | if (!entry) | |
3511 | return 0; | |
b448c4e3 | 3512 | |
33dc9b12 | 3513 | free_hash_entry(hash, entry); |
1cf41dd7 SR |
3514 | } else { |
3515 | /* Do nothing if it exists */ | |
3516 | if (entry) | |
3517 | return 0; | |
b448c4e3 | 3518 | |
1cf41dd7 | 3519 | ret = add_hash_entry(hash, rec->ip); |
b448c4e3 SR |
3520 | } |
3521 | return ret; | |
996e87be SR |
3522 | } |
3523 | ||
64e7c440 | 3524 | static int |
0b507e1e DS |
3525 | ftrace_match_record(struct dyn_ftrace *rec, struct ftrace_glob *func_g, |
3526 | struct ftrace_glob *mod_g, int exclude_mod) | |
64e7c440 SR |
3527 | { |
3528 | char str[KSYM_SYMBOL_LEN]; | |
b9df92d2 SR |
3529 | char *modname; |
3530 | ||
3531 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); | |
3532 | ||
0b507e1e DS |
3533 | if (mod_g) { |
3534 | int mod_matches = (modname) ? ftrace_match(modname, mod_g) : 0; | |
3535 | ||
3536 | /* blank module name to match all modules */ | |
3537 | if (!mod_g->len) { | |
3538 | /* blank module globbing: modname xor exclude_mod */ | |
3539 | if ((!exclude_mod) != (!modname)) | |
3540 | goto func_match; | |
3541 | return 0; | |
3542 | } | |
3543 | ||
3544 | /* not matching the module */ | |
3545 | if (!modname || !mod_matches) { | |
3546 | if (exclude_mod) | |
3547 | goto func_match; | |
3548 | else | |
3549 | return 0; | |
3550 | } | |
3551 | ||
3552 | if (mod_matches && exclude_mod) | |
b9df92d2 SR |
3553 | return 0; |
3554 | ||
0b507e1e | 3555 | func_match: |
b9df92d2 | 3556 | /* blank search means to match all funcs in the mod */ |
3ba00929 | 3557 | if (!func_g->len) |
b9df92d2 SR |
3558 | return 1; |
3559 | } | |
64e7c440 | 3560 | |
3ba00929 | 3561 | return ftrace_match(str, func_g); |
64e7c440 SR |
3562 | } |
3563 | ||
1cf41dd7 | 3564 | static int |
3ba00929 | 3565 | match_records(struct ftrace_hash *hash, char *func, int len, char *mod) |
9f4801e3 | 3566 | { |
9f4801e3 SR |
3567 | struct ftrace_page *pg; |
3568 | struct dyn_ftrace *rec; | |
3ba00929 | 3569 | struct ftrace_glob func_g = { .type = MATCH_FULL }; |
0b507e1e DS |
3570 | struct ftrace_glob mod_g = { .type = MATCH_FULL }; |
3571 | struct ftrace_glob *mod_match = (mod) ? &mod_g : NULL; | |
3572 | int exclude_mod = 0; | |
311d16da | 3573 | int found = 0; |
b448c4e3 | 3574 | int ret; |
f0a3b154 | 3575 | int clear_filter; |
9f4801e3 | 3576 | |
0b507e1e | 3577 | if (func) { |
3ba00929 DS |
3578 | func_g.type = filter_parse_regex(func, len, &func_g.search, |
3579 | &clear_filter); | |
3580 | func_g.len = strlen(func_g.search); | |
b9df92d2 | 3581 | } |
9f4801e3 | 3582 | |
0b507e1e DS |
3583 | if (mod) { |
3584 | mod_g.type = filter_parse_regex(mod, strlen(mod), | |
3585 | &mod_g.search, &exclude_mod); | |
3586 | mod_g.len = strlen(mod_g.search); | |
b9df92d2 | 3587 | } |
9f4801e3 | 3588 | |
52baf119 | 3589 | mutex_lock(&ftrace_lock); |
265c831c | 3590 | |
b9df92d2 SR |
3591 | if (unlikely(ftrace_disabled)) |
3592 | goto out_unlock; | |
9f4801e3 | 3593 | |
265c831c | 3594 | do_for_each_ftrace_rec(pg, rec) { |
0b507e1e | 3595 | if (ftrace_match_record(rec, &func_g, mod_match, exclude_mod)) { |
f0a3b154 | 3596 | ret = enter_record(hash, rec, clear_filter); |
b448c4e3 SR |
3597 | if (ret < 0) { |
3598 | found = ret; | |
3599 | goto out_unlock; | |
3600 | } | |
311d16da | 3601 | found = 1; |
265c831c SR |
3602 | } |
3603 | } while_for_each_ftrace_rec(); | |
b9df92d2 | 3604 | out_unlock: |
52baf119 | 3605 | mutex_unlock(&ftrace_lock); |
311d16da LZ |
3606 | |
3607 | return found; | |
5072c59f SR |
3608 | } |
3609 | ||
64e7c440 | 3610 | static int |
1cf41dd7 | 3611 | ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) |
64e7c440 | 3612 | { |
f0a3b154 | 3613 | return match_records(hash, buff, len, NULL); |
64e7c440 SR |
3614 | } |
3615 | ||
64e7c440 | 3616 | |
f6180773 SR |
3617 | /* |
3618 | * We register the module command as a template to show others how | |
3619 | * to register the a command as well. | |
3620 | */ | |
3621 | ||
3622 | static int | |
43dd61c9 | 3623 | ftrace_mod_callback(struct ftrace_hash *hash, |
f0a3b154 | 3624 | char *func, char *cmd, char *module, int enable) |
f6180773 | 3625 | { |
5e3949f0 | 3626 | int ret; |
f6180773 SR |
3627 | |
3628 | /* | |
3629 | * cmd == 'mod' because we only registered this func | |
3630 | * for the 'mod' ftrace_func_command. | |
3631 | * But if you register one func with multiple commands, | |
3632 | * you can tell which command was used by the cmd | |
3633 | * parameter. | |
3634 | */ | |
f0a3b154 | 3635 | ret = match_records(hash, func, strlen(func), module); |
b448c4e3 | 3636 | if (!ret) |
5e3949f0 | 3637 | return -EINVAL; |
b448c4e3 SR |
3638 | if (ret < 0) |
3639 | return ret; | |
b448c4e3 | 3640 | return 0; |
f6180773 SR |
3641 | } |
3642 | ||
3643 | static struct ftrace_func_command ftrace_mod_cmd = { | |
3644 | .name = "mod", | |
3645 | .func = ftrace_mod_callback, | |
3646 | }; | |
3647 | ||
3648 | static int __init ftrace_mod_cmd_init(void) | |
3649 | { | |
3650 | return register_ftrace_command(&ftrace_mod_cmd); | |
3651 | } | |
6f415672 | 3652 | core_initcall(ftrace_mod_cmd_init); |
f6180773 | 3653 | |
2f5f6ad9 | 3654 | static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 3655 | struct ftrace_ops *op, struct pt_regs *pt_regs) |
59df055f | 3656 | { |
b6887d79 | 3657 | struct ftrace_func_probe *entry; |
59df055f | 3658 | struct hlist_head *hhd; |
59df055f | 3659 | unsigned long key; |
59df055f SR |
3660 | |
3661 | key = hash_long(ip, FTRACE_HASH_BITS); | |
3662 | ||
3663 | hhd = &ftrace_func_hash[key]; | |
3664 | ||
3665 | if (hlist_empty(hhd)) | |
3666 | return; | |
3667 | ||
3668 | /* | |
3669 | * Disable preemption for these calls to prevent a RCU grace | |
3670 | * period. This syncs the hash iteration and freeing of items | |
3671 | * on the hash. rcu_read_lock is too dangerous here. | |
3672 | */ | |
5168ae50 | 3673 | preempt_disable_notrace(); |
1bb539ca | 3674 | hlist_for_each_entry_rcu_notrace(entry, hhd, node) { |
59df055f SR |
3675 | if (entry->ip == ip) |
3676 | entry->ops->func(ip, parent_ip, &entry->data); | |
3677 | } | |
5168ae50 | 3678 | preempt_enable_notrace(); |
59df055f SR |
3679 | } |
3680 | ||
b6887d79 | 3681 | static struct ftrace_ops trace_probe_ops __read_mostly = |
59df055f | 3682 | { |
fb9fb015 | 3683 | .func = function_trace_probe_call, |
f04f24fb | 3684 | .flags = FTRACE_OPS_FL_INITIALIZED, |
33b7f99c | 3685 | INIT_OPS_HASH(trace_probe_ops) |
59df055f SR |
3686 | }; |
3687 | ||
b6887d79 | 3688 | static int ftrace_probe_registered; |
59df055f | 3689 | |
7485058e | 3690 | static void __enable_ftrace_function_probe(struct ftrace_ops_hash *old_hash) |
59df055f | 3691 | { |
b848914c | 3692 | int ret; |
59df055f SR |
3693 | int i; |
3694 | ||
19dd603e SRRH |
3695 | if (ftrace_probe_registered) { |
3696 | /* still need to update the function call sites */ | |
3697 | if (ftrace_enabled) | |
8252ecf3 SRRH |
3698 | ftrace_run_modify_code(&trace_probe_ops, FTRACE_UPDATE_CALLS, |
3699 | old_hash); | |
59df055f | 3700 | return; |
19dd603e | 3701 | } |
59df055f SR |
3702 | |
3703 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
3704 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3705 | if (hhd->first) | |
3706 | break; | |
3707 | } | |
3708 | /* Nothing registered? */ | |
3709 | if (i == FTRACE_FUNC_HASHSIZE) | |
3710 | return; | |
3711 | ||
8a56d776 | 3712 | ret = ftrace_startup(&trace_probe_ops, 0); |
b848914c | 3713 | |
b6887d79 | 3714 | ftrace_probe_registered = 1; |
59df055f SR |
3715 | } |
3716 | ||
b6887d79 | 3717 | static void __disable_ftrace_function_probe(void) |
59df055f SR |
3718 | { |
3719 | int i; | |
3720 | ||
b6887d79 | 3721 | if (!ftrace_probe_registered) |
59df055f SR |
3722 | return; |
3723 | ||
3724 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
3725 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3726 | if (hhd->first) | |
3727 | return; | |
3728 | } | |
3729 | ||
3730 | /* no more funcs left */ | |
8a56d776 | 3731 | ftrace_shutdown(&trace_probe_ops, 0); |
b848914c | 3732 | |
b6887d79 | 3733 | ftrace_probe_registered = 0; |
59df055f SR |
3734 | } |
3735 | ||
3736 | ||
7818b388 | 3737 | static void ftrace_free_entry(struct ftrace_func_probe *entry) |
59df055f | 3738 | { |
59df055f | 3739 | if (entry->ops->free) |
e67efb93 | 3740 | entry->ops->free(entry->ops, entry->ip, &entry->data); |
59df055f SR |
3741 | kfree(entry); |
3742 | } | |
3743 | ||
59df055f | 3744 | int |
b6887d79 | 3745 | register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3746 | void *data) |
3747 | { | |
7485058e | 3748 | struct ftrace_ops_hash old_hash_ops; |
b6887d79 | 3749 | struct ftrace_func_probe *entry; |
3ba00929 | 3750 | struct ftrace_glob func_g; |
33b7f99c | 3751 | struct ftrace_hash **orig_hash = &trace_probe_ops.func_hash->filter_hash; |
3296fc4e | 3752 | struct ftrace_hash *old_hash = *orig_hash; |
e1df4cb6 | 3753 | struct ftrace_hash *hash; |
59df055f SR |
3754 | struct ftrace_page *pg; |
3755 | struct dyn_ftrace *rec; | |
3ba00929 | 3756 | int not; |
6a24a244 | 3757 | unsigned long key; |
59df055f | 3758 | int count = 0; |
e1df4cb6 | 3759 | int ret; |
59df055f | 3760 | |
3ba00929 DS |
3761 | func_g.type = filter_parse_regex(glob, strlen(glob), |
3762 | &func_g.search, ¬); | |
3763 | func_g.len = strlen(func_g.search); | |
59df055f | 3764 | |
b6887d79 | 3765 | /* we do not support '!' for function probes */ |
59df055f SR |
3766 | if (WARN_ON(not)) |
3767 | return -EINVAL; | |
3768 | ||
33b7f99c | 3769 | mutex_lock(&trace_probe_ops.func_hash->regex_lock); |
59df055f | 3770 | |
7485058e SRRH |
3771 | old_hash_ops.filter_hash = old_hash; |
3772 | /* Probes only have filters */ | |
3773 | old_hash_ops.notrace_hash = NULL; | |
3774 | ||
3296fc4e | 3775 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash); |
e1df4cb6 SRRH |
3776 | if (!hash) { |
3777 | count = -ENOMEM; | |
5ae0bf59 | 3778 | goto out; |
e1df4cb6 SRRH |
3779 | } |
3780 | ||
3781 | if (unlikely(ftrace_disabled)) { | |
3782 | count = -ENODEV; | |
5ae0bf59 | 3783 | goto out; |
e1df4cb6 | 3784 | } |
59df055f | 3785 | |
5ae0bf59 SRRH |
3786 | mutex_lock(&ftrace_lock); |
3787 | ||
45a4a237 | 3788 | do_for_each_ftrace_rec(pg, rec) { |
59df055f | 3789 | |
0b507e1e | 3790 | if (!ftrace_match_record(rec, &func_g, NULL, 0)) |
59df055f SR |
3791 | continue; |
3792 | ||
3793 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
3794 | if (!entry) { | |
b6887d79 | 3795 | /* If we did not process any, then return error */ |
59df055f SR |
3796 | if (!count) |
3797 | count = -ENOMEM; | |
3798 | goto out_unlock; | |
3799 | } | |
3800 | ||
3801 | count++; | |
3802 | ||
3803 | entry->data = data; | |
3804 | ||
3805 | /* | |
3806 | * The caller might want to do something special | |
3807 | * for each function we find. We call the callback | |
3808 | * to give the caller an opportunity to do so. | |
3809 | */ | |
e67efb93 SRRH |
3810 | if (ops->init) { |
3811 | if (ops->init(ops, rec->ip, &entry->data) < 0) { | |
59df055f SR |
3812 | /* caller does not like this func */ |
3813 | kfree(entry); | |
3814 | continue; | |
3815 | } | |
3816 | } | |
3817 | ||
e1df4cb6 SRRH |
3818 | ret = enter_record(hash, rec, 0); |
3819 | if (ret < 0) { | |
3820 | kfree(entry); | |
3821 | count = ret; | |
3822 | goto out_unlock; | |
3823 | } | |
3824 | ||
59df055f SR |
3825 | entry->ops = ops; |
3826 | entry->ip = rec->ip; | |
3827 | ||
3828 | key = hash_long(entry->ip, FTRACE_HASH_BITS); | |
3829 | hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]); | |
3830 | ||
3831 | } while_for_each_ftrace_rec(); | |
e1df4cb6 SRRH |
3832 | |
3833 | ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash); | |
8252ecf3 | 3834 | |
7485058e | 3835 | __enable_ftrace_function_probe(&old_hash_ops); |
8252ecf3 | 3836 | |
3296fc4e SRRH |
3837 | if (!ret) |
3838 | free_ftrace_hash_rcu(old_hash); | |
3839 | else | |
e1df4cb6 SRRH |
3840 | count = ret; |
3841 | ||
59df055f | 3842 | out_unlock: |
5ae0bf59 SRRH |
3843 | mutex_unlock(&ftrace_lock); |
3844 | out: | |
33b7f99c | 3845 | mutex_unlock(&trace_probe_ops.func_hash->regex_lock); |
e1df4cb6 | 3846 | free_ftrace_hash(hash); |
59df055f SR |
3847 | |
3848 | return count; | |
3849 | } | |
3850 | ||
3851 | enum { | |
b6887d79 SR |
3852 | PROBE_TEST_FUNC = 1, |
3853 | PROBE_TEST_DATA = 2 | |
59df055f SR |
3854 | }; |
3855 | ||
3856 | static void | |
b6887d79 | 3857 | __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3858 | void *data, int flags) |
3859 | { | |
e1df4cb6 | 3860 | struct ftrace_func_entry *rec_entry; |
b6887d79 | 3861 | struct ftrace_func_probe *entry; |
7818b388 | 3862 | struct ftrace_func_probe *p; |
3ba00929 | 3863 | struct ftrace_glob func_g; |
33b7f99c | 3864 | struct ftrace_hash **orig_hash = &trace_probe_ops.func_hash->filter_hash; |
3296fc4e | 3865 | struct ftrace_hash *old_hash = *orig_hash; |
7818b388 | 3866 | struct list_head free_list; |
e1df4cb6 | 3867 | struct ftrace_hash *hash; |
b67bfe0d | 3868 | struct hlist_node *tmp; |
59df055f | 3869 | char str[KSYM_SYMBOL_LEN]; |
3ba00929 | 3870 | int i, ret; |
59df055f | 3871 | |
b36461da | 3872 | if (glob && (strcmp(glob, "*") == 0 || !strlen(glob))) |
3ba00929 | 3873 | func_g.search = NULL; |
b36461da | 3874 | else if (glob) { |
59df055f SR |
3875 | int not; |
3876 | ||
3ba00929 DS |
3877 | func_g.type = filter_parse_regex(glob, strlen(glob), |
3878 | &func_g.search, ¬); | |
3879 | func_g.len = strlen(func_g.search); | |
3880 | func_g.search = glob; | |
59df055f | 3881 | |
b6887d79 | 3882 | /* we do not support '!' for function probes */ |
59df055f SR |
3883 | if (WARN_ON(not)) |
3884 | return; | |
3885 | } | |
3886 | ||
33b7f99c | 3887 | mutex_lock(&trace_probe_ops.func_hash->regex_lock); |
e1df4cb6 SRRH |
3888 | |
3889 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
3890 | if (!hash) | |
3891 | /* Hmm, should report this somehow */ | |
3892 | goto out_unlock; | |
3893 | ||
7818b388 SRRH |
3894 | INIT_LIST_HEAD(&free_list); |
3895 | ||
59df055f SR |
3896 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { |
3897 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3898 | ||
b67bfe0d | 3899 | hlist_for_each_entry_safe(entry, tmp, hhd, node) { |
59df055f SR |
3900 | |
3901 | /* break up if statements for readability */ | |
b6887d79 | 3902 | if ((flags & PROBE_TEST_FUNC) && entry->ops != ops) |
59df055f SR |
3903 | continue; |
3904 | ||
b6887d79 | 3905 | if ((flags & PROBE_TEST_DATA) && entry->data != data) |
59df055f SR |
3906 | continue; |
3907 | ||
3908 | /* do this last, since it is the most expensive */ | |
3ba00929 | 3909 | if (func_g.search) { |
59df055f SR |
3910 | kallsyms_lookup(entry->ip, NULL, NULL, |
3911 | NULL, str); | |
3ba00929 | 3912 | if (!ftrace_match(str, &func_g)) |
59df055f SR |
3913 | continue; |
3914 | } | |
3915 | ||
e1df4cb6 SRRH |
3916 | rec_entry = ftrace_lookup_ip(hash, entry->ip); |
3917 | /* It is possible more than one entry had this ip */ | |
3918 | if (rec_entry) | |
3919 | free_hash_entry(hash, rec_entry); | |
3920 | ||
740466bc | 3921 | hlist_del_rcu(&entry->node); |
7818b388 | 3922 | list_add(&entry->free_list, &free_list); |
59df055f SR |
3923 | } |
3924 | } | |
3f2367ba | 3925 | mutex_lock(&ftrace_lock); |
b6887d79 | 3926 | __disable_ftrace_function_probe(); |
e1df4cb6 SRRH |
3927 | /* |
3928 | * Remove after the disable is called. Otherwise, if the last | |
3929 | * probe is removed, a null hash means *all enabled*. | |
3930 | */ | |
3296fc4e | 3931 | ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash); |
7818b388 | 3932 | synchronize_sched(); |
3296fc4e SRRH |
3933 | if (!ret) |
3934 | free_ftrace_hash_rcu(old_hash); | |
3935 | ||
7818b388 SRRH |
3936 | list_for_each_entry_safe(entry, p, &free_list, free_list) { |
3937 | list_del(&entry->free_list); | |
3938 | ftrace_free_entry(entry); | |
3939 | } | |
3f2367ba | 3940 | mutex_unlock(&ftrace_lock); |
3ba00929 | 3941 | |
e1df4cb6 | 3942 | out_unlock: |
33b7f99c | 3943 | mutex_unlock(&trace_probe_ops.func_hash->regex_lock); |
e1df4cb6 | 3944 | free_ftrace_hash(hash); |
59df055f SR |
3945 | } |
3946 | ||
3947 | void | |
b6887d79 | 3948 | unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3949 | void *data) |
3950 | { | |
b6887d79 SR |
3951 | __unregister_ftrace_function_probe(glob, ops, data, |
3952 | PROBE_TEST_FUNC | PROBE_TEST_DATA); | |
59df055f SR |
3953 | } |
3954 | ||
3955 | void | |
b6887d79 | 3956 | unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops) |
59df055f | 3957 | { |
b6887d79 | 3958 | __unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC); |
59df055f SR |
3959 | } |
3960 | ||
b6887d79 | 3961 | void unregister_ftrace_function_probe_all(char *glob) |
59df055f | 3962 | { |
b6887d79 | 3963 | __unregister_ftrace_function_probe(glob, NULL, NULL, 0); |
59df055f SR |
3964 | } |
3965 | ||
f6180773 SR |
3966 | static LIST_HEAD(ftrace_commands); |
3967 | static DEFINE_MUTEX(ftrace_cmd_mutex); | |
3968 | ||
38de93ab TZ |
3969 | /* |
3970 | * Currently we only register ftrace commands from __init, so mark this | |
3971 | * __init too. | |
3972 | */ | |
3973 | __init int register_ftrace_command(struct ftrace_func_command *cmd) | |
f6180773 SR |
3974 | { |
3975 | struct ftrace_func_command *p; | |
3976 | int ret = 0; | |
3977 | ||
3978 | mutex_lock(&ftrace_cmd_mutex); | |
3979 | list_for_each_entry(p, &ftrace_commands, list) { | |
3980 | if (strcmp(cmd->name, p->name) == 0) { | |
3981 | ret = -EBUSY; | |
3982 | goto out_unlock; | |
3983 | } | |
3984 | } | |
3985 | list_add(&cmd->list, &ftrace_commands); | |
3986 | out_unlock: | |
3987 | mutex_unlock(&ftrace_cmd_mutex); | |
3988 | ||
3989 | return ret; | |
3990 | } | |
3991 | ||
38de93ab TZ |
3992 | /* |
3993 | * Currently we only unregister ftrace commands from __init, so mark | |
3994 | * this __init too. | |
3995 | */ | |
3996 | __init int unregister_ftrace_command(struct ftrace_func_command *cmd) | |
f6180773 SR |
3997 | { |
3998 | struct ftrace_func_command *p, *n; | |
3999 | int ret = -ENODEV; | |
4000 | ||
4001 | mutex_lock(&ftrace_cmd_mutex); | |
4002 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { | |
4003 | if (strcmp(cmd->name, p->name) == 0) { | |
4004 | ret = 0; | |
4005 | list_del_init(&p->list); | |
4006 | goto out_unlock; | |
4007 | } | |
4008 | } | |
4009 | out_unlock: | |
4010 | mutex_unlock(&ftrace_cmd_mutex); | |
4011 | ||
4012 | return ret; | |
4013 | } | |
4014 | ||
33dc9b12 SR |
4015 | static int ftrace_process_regex(struct ftrace_hash *hash, |
4016 | char *buff, int len, int enable) | |
64e7c440 | 4017 | { |
f6180773 | 4018 | char *func, *command, *next = buff; |
6a24a244 | 4019 | struct ftrace_func_command *p; |
0aff1c0c | 4020 | int ret = -EINVAL; |
64e7c440 SR |
4021 | |
4022 | func = strsep(&next, ":"); | |
4023 | ||
4024 | if (!next) { | |
1cf41dd7 | 4025 | ret = ftrace_match_records(hash, func, len); |
b448c4e3 SR |
4026 | if (!ret) |
4027 | ret = -EINVAL; | |
4028 | if (ret < 0) | |
4029 | return ret; | |
4030 | return 0; | |
64e7c440 SR |
4031 | } |
4032 | ||
f6180773 | 4033 | /* command found */ |
64e7c440 SR |
4034 | |
4035 | command = strsep(&next, ":"); | |
4036 | ||
f6180773 SR |
4037 | mutex_lock(&ftrace_cmd_mutex); |
4038 | list_for_each_entry(p, &ftrace_commands, list) { | |
4039 | if (strcmp(p->name, command) == 0) { | |
43dd61c9 | 4040 | ret = p->func(hash, func, command, next, enable); |
f6180773 SR |
4041 | goto out_unlock; |
4042 | } | |
64e7c440 | 4043 | } |
f6180773 SR |
4044 | out_unlock: |
4045 | mutex_unlock(&ftrace_cmd_mutex); | |
64e7c440 | 4046 | |
f6180773 | 4047 | return ret; |
64e7c440 SR |
4048 | } |
4049 | ||
e309b41d | 4050 | static ssize_t |
41c52c0d SR |
4051 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
4052 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
4053 | { |
4054 | struct ftrace_iterator *iter; | |
689fd8b6 | 4055 | struct trace_parser *parser; |
4056 | ssize_t ret, read; | |
5072c59f | 4057 | |
4ba7978e | 4058 | if (!cnt) |
5072c59f SR |
4059 | return 0; |
4060 | ||
5072c59f SR |
4061 | if (file->f_mode & FMODE_READ) { |
4062 | struct seq_file *m = file->private_data; | |
4063 | iter = m->private; | |
4064 | } else | |
4065 | iter = file->private_data; | |
4066 | ||
f04f24fb | 4067 | if (unlikely(ftrace_disabled)) |
3f2367ba MH |
4068 | return -ENODEV; |
4069 | ||
4070 | /* iter->hash is a local copy, so we don't need regex_lock */ | |
f04f24fb | 4071 | |
689fd8b6 | 4072 | parser = &iter->parser; |
4073 | read = trace_get_user(parser, ubuf, cnt, ppos); | |
5072c59f | 4074 | |
4ba7978e | 4075 | if (read >= 0 && trace_parser_loaded(parser) && |
689fd8b6 | 4076 | !trace_parser_cont(parser)) { |
33dc9b12 | 4077 | ret = ftrace_process_regex(iter->hash, parser->buffer, |
689fd8b6 | 4078 | parser->idx, enable); |
313254a9 | 4079 | trace_parser_clear(parser); |
7c088b51 | 4080 | if (ret < 0) |
3f2367ba | 4081 | goto out; |
eda1e328 | 4082 | } |
5072c59f | 4083 | |
5072c59f | 4084 | ret = read; |
3f2367ba | 4085 | out: |
5072c59f SR |
4086 | return ret; |
4087 | } | |
4088 | ||
fc13cb0c | 4089 | ssize_t |
41c52c0d SR |
4090 | ftrace_filter_write(struct file *file, const char __user *ubuf, |
4091 | size_t cnt, loff_t *ppos) | |
4092 | { | |
4093 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
4094 | } | |
4095 | ||
fc13cb0c | 4096 | ssize_t |
41c52c0d SR |
4097 | ftrace_notrace_write(struct file *file, const char __user *ubuf, |
4098 | size_t cnt, loff_t *ppos) | |
4099 | { | |
4100 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
4101 | } | |
4102 | ||
33dc9b12 | 4103 | static int |
647664ea MH |
4104 | ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) |
4105 | { | |
4106 | struct ftrace_func_entry *entry; | |
4107 | ||
4108 | if (!ftrace_location(ip)) | |
4109 | return -EINVAL; | |
4110 | ||
4111 | if (remove) { | |
4112 | entry = ftrace_lookup_ip(hash, ip); | |
4113 | if (!entry) | |
4114 | return -ENOENT; | |
4115 | free_hash_entry(hash, entry); | |
4116 | return 0; | |
4117 | } | |
4118 | ||
4119 | return add_hash_entry(hash, ip); | |
4120 | } | |
4121 | ||
8252ecf3 | 4122 | static void ftrace_ops_update_code(struct ftrace_ops *ops, |
7485058e | 4123 | struct ftrace_ops_hash *old_hash) |
1c80c432 | 4124 | { |
8f86f837 SRRH |
4125 | struct ftrace_ops *op; |
4126 | ||
4127 | if (!ftrace_enabled) | |
4128 | return; | |
4129 | ||
4130 | if (ops->flags & FTRACE_OPS_FL_ENABLED) { | |
8252ecf3 | 4131 | ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS, old_hash); |
8f86f837 SRRH |
4132 | return; |
4133 | } | |
4134 | ||
4135 | /* | |
4136 | * If this is the shared global_ops filter, then we need to | |
4137 | * check if there is another ops that shares it, is enabled. | |
4138 | * If so, we still need to run the modify code. | |
4139 | */ | |
4140 | if (ops->func_hash != &global_ops.local_hash) | |
4141 | return; | |
4142 | ||
4143 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
4144 | if (op->func_hash == &global_ops.local_hash && | |
4145 | op->flags & FTRACE_OPS_FL_ENABLED) { | |
4146 | ftrace_run_modify_code(op, FTRACE_UPDATE_CALLS, old_hash); | |
4147 | /* Only need to do this once */ | |
4148 | return; | |
4149 | } | |
4150 | } while_for_each_ftrace_op(op); | |
1c80c432 SRRH |
4151 | } |
4152 | ||
647664ea MH |
4153 | static int |
4154 | ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, | |
4155 | unsigned long ip, int remove, int reset, int enable) | |
41c52c0d | 4156 | { |
33dc9b12 | 4157 | struct ftrace_hash **orig_hash; |
7485058e | 4158 | struct ftrace_ops_hash old_hash_ops; |
3296fc4e | 4159 | struct ftrace_hash *old_hash; |
f45948e8 | 4160 | struct ftrace_hash *hash; |
33dc9b12 | 4161 | int ret; |
f45948e8 | 4162 | |
41c52c0d | 4163 | if (unlikely(ftrace_disabled)) |
33dc9b12 | 4164 | return -ENODEV; |
41c52c0d | 4165 | |
33b7f99c | 4166 | mutex_lock(&ops->func_hash->regex_lock); |
3f2367ba | 4167 | |
f45948e8 | 4168 | if (enable) |
33b7f99c | 4169 | orig_hash = &ops->func_hash->filter_hash; |
f45948e8 | 4170 | else |
33b7f99c | 4171 | orig_hash = &ops->func_hash->notrace_hash; |
33dc9b12 | 4172 | |
b972cc58 WN |
4173 | if (reset) |
4174 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); | |
4175 | else | |
4176 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
4177 | ||
3f2367ba MH |
4178 | if (!hash) { |
4179 | ret = -ENOMEM; | |
4180 | goto out_regex_unlock; | |
4181 | } | |
f45948e8 | 4182 | |
ac483c44 JO |
4183 | if (buf && !ftrace_match_records(hash, buf, len)) { |
4184 | ret = -EINVAL; | |
4185 | goto out_regex_unlock; | |
4186 | } | |
647664ea MH |
4187 | if (ip) { |
4188 | ret = ftrace_match_addr(hash, ip, remove); | |
4189 | if (ret < 0) | |
4190 | goto out_regex_unlock; | |
4191 | } | |
33dc9b12 SR |
4192 | |
4193 | mutex_lock(&ftrace_lock); | |
3296fc4e | 4194 | old_hash = *orig_hash; |
7485058e SRRH |
4195 | old_hash_ops.filter_hash = ops->func_hash->filter_hash; |
4196 | old_hash_ops.notrace_hash = ops->func_hash->notrace_hash; | |
41fb61c2 | 4197 | ret = ftrace_hash_move(ops, enable, orig_hash, hash); |
3296fc4e | 4198 | if (!ret) { |
7485058e | 4199 | ftrace_ops_update_code(ops, &old_hash_ops); |
3296fc4e SRRH |
4200 | free_ftrace_hash_rcu(old_hash); |
4201 | } | |
33dc9b12 SR |
4202 | mutex_unlock(&ftrace_lock); |
4203 | ||
ac483c44 | 4204 | out_regex_unlock: |
33b7f99c | 4205 | mutex_unlock(&ops->func_hash->regex_lock); |
33dc9b12 SR |
4206 | |
4207 | free_ftrace_hash(hash); | |
4208 | return ret; | |
41c52c0d SR |
4209 | } |
4210 | ||
647664ea MH |
4211 | static int |
4212 | ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove, | |
4213 | int reset, int enable) | |
4214 | { | |
4215 | return ftrace_set_hash(ops, 0, 0, ip, remove, reset, enable); | |
4216 | } | |
4217 | ||
4218 | /** | |
4219 | * ftrace_set_filter_ip - set a function to filter on in ftrace by address | |
4220 | * @ops - the ops to set the filter with | |
4221 | * @ip - the address to add to or remove from the filter. | |
4222 | * @remove - non zero to remove the ip from the filter | |
4223 | * @reset - non zero to reset all filters before applying this filter. | |
4224 | * | |
4225 | * Filters denote which functions should be enabled when tracing is enabled | |
4226 | * If @ip is NULL, it failes to update filter. | |
4227 | */ | |
4228 | int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, | |
4229 | int remove, int reset) | |
4230 | { | |
f04f24fb | 4231 | ftrace_ops_init(ops); |
647664ea MH |
4232 | return ftrace_set_addr(ops, ip, remove, reset, 1); |
4233 | } | |
4234 | EXPORT_SYMBOL_GPL(ftrace_set_filter_ip); | |
4235 | ||
4236 | static int | |
4237 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, | |
4238 | int reset, int enable) | |
4239 | { | |
4240 | return ftrace_set_hash(ops, buf, len, 0, 0, reset, enable); | |
4241 | } | |
4242 | ||
77a2b37d SR |
4243 | /** |
4244 | * ftrace_set_filter - set a function to filter on in ftrace | |
936e074b SR |
4245 | * @ops - the ops to set the filter with |
4246 | * @buf - the string that holds the function filter text. | |
4247 | * @len - the length of the string. | |
4248 | * @reset - non zero to reset all filters before applying this filter. | |
4249 | * | |
4250 | * Filters denote which functions should be enabled when tracing is enabled. | |
4251 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
4252 | */ | |
ac483c44 | 4253 | int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
4254 | int len, int reset) |
4255 | { | |
f04f24fb | 4256 | ftrace_ops_init(ops); |
ac483c44 | 4257 | return ftrace_set_regex(ops, buf, len, reset, 1); |
936e074b SR |
4258 | } |
4259 | EXPORT_SYMBOL_GPL(ftrace_set_filter); | |
4260 | ||
4261 | /** | |
4262 | * ftrace_set_notrace - set a function to not trace in ftrace | |
4263 | * @ops - the ops to set the notrace filter with | |
4264 | * @buf - the string that holds the function notrace text. | |
4265 | * @len - the length of the string. | |
4266 | * @reset - non zero to reset all filters before applying this filter. | |
4267 | * | |
4268 | * Notrace Filters denote which functions should not be enabled when tracing | |
4269 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
4270 | * for tracing. | |
4271 | */ | |
ac483c44 | 4272 | int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
4273 | int len, int reset) |
4274 | { | |
f04f24fb | 4275 | ftrace_ops_init(ops); |
ac483c44 | 4276 | return ftrace_set_regex(ops, buf, len, reset, 0); |
936e074b SR |
4277 | } |
4278 | EXPORT_SYMBOL_GPL(ftrace_set_notrace); | |
4279 | /** | |
8d1b065d | 4280 | * ftrace_set_global_filter - set a function to filter on with global tracers |
77a2b37d SR |
4281 | * @buf - the string that holds the function filter text. |
4282 | * @len - the length of the string. | |
4283 | * @reset - non zero to reset all filters before applying this filter. | |
4284 | * | |
4285 | * Filters denote which functions should be enabled when tracing is enabled. | |
4286 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
4287 | */ | |
936e074b | 4288 | void ftrace_set_global_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 4289 | { |
f45948e8 | 4290 | ftrace_set_regex(&global_ops, buf, len, reset, 1); |
41c52c0d | 4291 | } |
936e074b | 4292 | EXPORT_SYMBOL_GPL(ftrace_set_global_filter); |
4eebcc81 | 4293 | |
41c52c0d | 4294 | /** |
8d1b065d | 4295 | * ftrace_set_global_notrace - set a function to not trace with global tracers |
41c52c0d SR |
4296 | * @buf - the string that holds the function notrace text. |
4297 | * @len - the length of the string. | |
4298 | * @reset - non zero to reset all filters before applying this filter. | |
4299 | * | |
4300 | * Notrace Filters denote which functions should not be enabled when tracing | |
4301 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
4302 | * for tracing. | |
4303 | */ | |
936e074b | 4304 | void ftrace_set_global_notrace(unsigned char *buf, int len, int reset) |
41c52c0d | 4305 | { |
f45948e8 | 4306 | ftrace_set_regex(&global_ops, buf, len, reset, 0); |
77a2b37d | 4307 | } |
936e074b | 4308 | EXPORT_SYMBOL_GPL(ftrace_set_global_notrace); |
77a2b37d | 4309 | |
2af15d6a SR |
4310 | /* |
4311 | * command line interface to allow users to set filters on boot up. | |
4312 | */ | |
4313 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE | |
4314 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; | |
4315 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; | |
4316 | ||
f1ed7c74 SRRH |
4317 | /* Used by function selftest to not test if filter is set */ |
4318 | bool ftrace_filter_param __initdata; | |
4319 | ||
2af15d6a SR |
4320 | static int __init set_ftrace_notrace(char *str) |
4321 | { | |
f1ed7c74 | 4322 | ftrace_filter_param = true; |
75761cc1 | 4323 | strlcpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
4324 | return 1; |
4325 | } | |
4326 | __setup("ftrace_notrace=", set_ftrace_notrace); | |
4327 | ||
4328 | static int __init set_ftrace_filter(char *str) | |
4329 | { | |
f1ed7c74 | 4330 | ftrace_filter_param = true; |
75761cc1 | 4331 | strlcpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
4332 | return 1; |
4333 | } | |
4334 | __setup("ftrace_filter=", set_ftrace_filter); | |
4335 | ||
369bc18f | 4336 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
f6060f46 | 4337 | static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; |
0d7d9a16 | 4338 | static char ftrace_graph_notrace_buf[FTRACE_FILTER_SIZE] __initdata; |
faf982a6 | 4339 | static int ftrace_set_func(unsigned long *array, int *idx, int size, char *buffer); |
801c29fd | 4340 | |
f3bea491 SRRH |
4341 | static unsigned long save_global_trampoline; |
4342 | static unsigned long save_global_flags; | |
4343 | ||
369bc18f SA |
4344 | static int __init set_graph_function(char *str) |
4345 | { | |
06f43d66 | 4346 | strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); |
369bc18f SA |
4347 | return 1; |
4348 | } | |
4349 | __setup("ftrace_graph_filter=", set_graph_function); | |
4350 | ||
0d7d9a16 NK |
4351 | static int __init set_graph_notrace_function(char *str) |
4352 | { | |
4353 | strlcpy(ftrace_graph_notrace_buf, str, FTRACE_FILTER_SIZE); | |
4354 | return 1; | |
4355 | } | |
4356 | __setup("ftrace_graph_notrace=", set_graph_notrace_function); | |
4357 | ||
4358 | static void __init set_ftrace_early_graph(char *buf, int enable) | |
369bc18f SA |
4359 | { |
4360 | int ret; | |
4361 | char *func; | |
0d7d9a16 NK |
4362 | unsigned long *table = ftrace_graph_funcs; |
4363 | int *count = &ftrace_graph_count; | |
4364 | ||
4365 | if (!enable) { | |
4366 | table = ftrace_graph_notrace_funcs; | |
4367 | count = &ftrace_graph_notrace_count; | |
4368 | } | |
369bc18f SA |
4369 | |
4370 | while (buf) { | |
4371 | func = strsep(&buf, ","); | |
4372 | /* we allow only one expression at a time */ | |
0d7d9a16 | 4373 | ret = ftrace_set_func(table, count, FTRACE_GRAPH_MAX_FUNCS, func); |
369bc18f SA |
4374 | if (ret) |
4375 | printk(KERN_DEBUG "ftrace: function %s not " | |
4376 | "traceable\n", func); | |
4377 | } | |
4378 | } | |
4379 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
4380 | ||
2a85a37f SR |
4381 | void __init |
4382 | ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable) | |
2af15d6a SR |
4383 | { |
4384 | char *func; | |
4385 | ||
f04f24fb MH |
4386 | ftrace_ops_init(ops); |
4387 | ||
2af15d6a SR |
4388 | while (buf) { |
4389 | func = strsep(&buf, ","); | |
f45948e8 | 4390 | ftrace_set_regex(ops, func, strlen(func), 0, enable); |
2af15d6a SR |
4391 | } |
4392 | } | |
4393 | ||
4394 | static void __init set_ftrace_early_filters(void) | |
4395 | { | |
4396 | if (ftrace_filter_buf[0]) | |
2a85a37f | 4397 | ftrace_set_early_filter(&global_ops, ftrace_filter_buf, 1); |
2af15d6a | 4398 | if (ftrace_notrace_buf[0]) |
2a85a37f | 4399 | ftrace_set_early_filter(&global_ops, ftrace_notrace_buf, 0); |
369bc18f SA |
4400 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
4401 | if (ftrace_graph_buf[0]) | |
0d7d9a16 NK |
4402 | set_ftrace_early_graph(ftrace_graph_buf, 1); |
4403 | if (ftrace_graph_notrace_buf[0]) | |
4404 | set_ftrace_early_graph(ftrace_graph_notrace_buf, 0); | |
369bc18f | 4405 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
2af15d6a SR |
4406 | } |
4407 | ||
fc13cb0c | 4408 | int ftrace_regex_release(struct inode *inode, struct file *file) |
5072c59f SR |
4409 | { |
4410 | struct seq_file *m = (struct seq_file *)file->private_data; | |
7485058e | 4411 | struct ftrace_ops_hash old_hash_ops; |
5072c59f | 4412 | struct ftrace_iterator *iter; |
33dc9b12 | 4413 | struct ftrace_hash **orig_hash; |
3296fc4e | 4414 | struct ftrace_hash *old_hash; |
689fd8b6 | 4415 | struct trace_parser *parser; |
ed926f9b | 4416 | int filter_hash; |
33dc9b12 | 4417 | int ret; |
5072c59f | 4418 | |
5072c59f SR |
4419 | if (file->f_mode & FMODE_READ) { |
4420 | iter = m->private; | |
5072c59f SR |
4421 | seq_release(inode, file); |
4422 | } else | |
4423 | iter = file->private_data; | |
4424 | ||
689fd8b6 | 4425 | parser = &iter->parser; |
4426 | if (trace_parser_loaded(parser)) { | |
4427 | parser->buffer[parser->idx] = 0; | |
1cf41dd7 | 4428 | ftrace_match_records(iter->hash, parser->buffer, parser->idx); |
5072c59f SR |
4429 | } |
4430 | ||
689fd8b6 | 4431 | trace_parser_put(parser); |
689fd8b6 | 4432 | |
33b7f99c | 4433 | mutex_lock(&iter->ops->func_hash->regex_lock); |
3f2367ba | 4434 | |
058e297d | 4435 | if (file->f_mode & FMODE_WRITE) { |
ed926f9b SR |
4436 | filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); |
4437 | ||
4438 | if (filter_hash) | |
33b7f99c | 4439 | orig_hash = &iter->ops->func_hash->filter_hash; |
ed926f9b | 4440 | else |
33b7f99c | 4441 | orig_hash = &iter->ops->func_hash->notrace_hash; |
33dc9b12 | 4442 | |
058e297d | 4443 | mutex_lock(&ftrace_lock); |
3296fc4e | 4444 | old_hash = *orig_hash; |
7485058e SRRH |
4445 | old_hash_ops.filter_hash = iter->ops->func_hash->filter_hash; |
4446 | old_hash_ops.notrace_hash = iter->ops->func_hash->notrace_hash; | |
41fb61c2 SR |
4447 | ret = ftrace_hash_move(iter->ops, filter_hash, |
4448 | orig_hash, iter->hash); | |
3296fc4e | 4449 | if (!ret) { |
7485058e | 4450 | ftrace_ops_update_code(iter->ops, &old_hash_ops); |
3296fc4e SRRH |
4451 | free_ftrace_hash_rcu(old_hash); |
4452 | } | |
058e297d SR |
4453 | mutex_unlock(&ftrace_lock); |
4454 | } | |
3f2367ba | 4455 | |
33b7f99c | 4456 | mutex_unlock(&iter->ops->func_hash->regex_lock); |
33dc9b12 SR |
4457 | free_ftrace_hash(iter->hash); |
4458 | kfree(iter); | |
058e297d | 4459 | |
5072c59f SR |
4460 | return 0; |
4461 | } | |
4462 | ||
5e2336a0 | 4463 | static const struct file_operations ftrace_avail_fops = { |
5072c59f SR |
4464 | .open = ftrace_avail_open, |
4465 | .read = seq_read, | |
4466 | .llseek = seq_lseek, | |
3be04b47 | 4467 | .release = seq_release_private, |
5072c59f SR |
4468 | }; |
4469 | ||
647bcd03 SR |
4470 | static const struct file_operations ftrace_enabled_fops = { |
4471 | .open = ftrace_enabled_open, | |
4472 | .read = seq_read, | |
4473 | .llseek = seq_lseek, | |
4474 | .release = seq_release_private, | |
4475 | }; | |
4476 | ||
5e2336a0 | 4477 | static const struct file_operations ftrace_filter_fops = { |
5072c59f | 4478 | .open = ftrace_filter_open, |
850a80cf | 4479 | .read = seq_read, |
5072c59f | 4480 | .write = ftrace_filter_write, |
098c879e | 4481 | .llseek = tracing_lseek, |
1cf41dd7 | 4482 | .release = ftrace_regex_release, |
5072c59f SR |
4483 | }; |
4484 | ||
5e2336a0 | 4485 | static const struct file_operations ftrace_notrace_fops = { |
41c52c0d | 4486 | .open = ftrace_notrace_open, |
850a80cf | 4487 | .read = seq_read, |
41c52c0d | 4488 | .write = ftrace_notrace_write, |
098c879e | 4489 | .llseek = tracing_lseek, |
1cf41dd7 | 4490 | .release = ftrace_regex_release, |
41c52c0d SR |
4491 | }; |
4492 | ||
ea4e2bc4 SR |
4493 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
4494 | ||
4495 | static DEFINE_MUTEX(graph_lock); | |
4496 | ||
4497 | int ftrace_graph_count; | |
29ad23b0 | 4498 | int ftrace_graph_notrace_count; |
ea4e2bc4 | 4499 | unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; |
29ad23b0 | 4500 | unsigned long ftrace_graph_notrace_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; |
ea4e2bc4 | 4501 | |
faf982a6 NK |
4502 | struct ftrace_graph_data { |
4503 | unsigned long *table; | |
4504 | size_t size; | |
4505 | int *count; | |
4506 | const struct seq_operations *seq_ops; | |
4507 | }; | |
4508 | ||
ea4e2bc4 | 4509 | static void * |
85951842 | 4510 | __g_next(struct seq_file *m, loff_t *pos) |
ea4e2bc4 | 4511 | { |
faf982a6 NK |
4512 | struct ftrace_graph_data *fgd = m->private; |
4513 | ||
4514 | if (*pos >= *fgd->count) | |
ea4e2bc4 | 4515 | return NULL; |
faf982a6 | 4516 | return &fgd->table[*pos]; |
85951842 | 4517 | } |
ea4e2bc4 | 4518 | |
85951842 LZ |
4519 | static void * |
4520 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
4521 | { | |
4522 | (*pos)++; | |
4523 | return __g_next(m, pos); | |
ea4e2bc4 SR |
4524 | } |
4525 | ||
4526 | static void *g_start(struct seq_file *m, loff_t *pos) | |
4527 | { | |
faf982a6 NK |
4528 | struct ftrace_graph_data *fgd = m->private; |
4529 | ||
ea4e2bc4 SR |
4530 | mutex_lock(&graph_lock); |
4531 | ||
f9349a8f | 4532 | /* Nothing, tell g_show to print all functions are enabled */ |
faf982a6 | 4533 | if (!*fgd->count && !*pos) |
f9349a8f FW |
4534 | return (void *)1; |
4535 | ||
85951842 | 4536 | return __g_next(m, pos); |
ea4e2bc4 SR |
4537 | } |
4538 | ||
4539 | static void g_stop(struct seq_file *m, void *p) | |
4540 | { | |
4541 | mutex_unlock(&graph_lock); | |
4542 | } | |
4543 | ||
4544 | static int g_show(struct seq_file *m, void *v) | |
4545 | { | |
4546 | unsigned long *ptr = v; | |
ea4e2bc4 SR |
4547 | |
4548 | if (!ptr) | |
4549 | return 0; | |
4550 | ||
f9349a8f | 4551 | if (ptr == (unsigned long *)1) { |
280d1429 NK |
4552 | struct ftrace_graph_data *fgd = m->private; |
4553 | ||
4554 | if (fgd->table == ftrace_graph_funcs) | |
fa6f0cc7 | 4555 | seq_puts(m, "#### all functions enabled ####\n"); |
280d1429 | 4556 | else |
fa6f0cc7 | 4557 | seq_puts(m, "#### no functions disabled ####\n"); |
f9349a8f FW |
4558 | return 0; |
4559 | } | |
4560 | ||
b375a11a | 4561 | seq_printf(m, "%ps\n", (void *)*ptr); |
ea4e2bc4 SR |
4562 | |
4563 | return 0; | |
4564 | } | |
4565 | ||
88e9d34c | 4566 | static const struct seq_operations ftrace_graph_seq_ops = { |
ea4e2bc4 SR |
4567 | .start = g_start, |
4568 | .next = g_next, | |
4569 | .stop = g_stop, | |
4570 | .show = g_show, | |
4571 | }; | |
4572 | ||
4573 | static int | |
faf982a6 NK |
4574 | __ftrace_graph_open(struct inode *inode, struct file *file, |
4575 | struct ftrace_graph_data *fgd) | |
ea4e2bc4 SR |
4576 | { |
4577 | int ret = 0; | |
4578 | ||
ea4e2bc4 SR |
4579 | mutex_lock(&graph_lock); |
4580 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 4581 | (file->f_flags & O_TRUNC)) { |
faf982a6 NK |
4582 | *fgd->count = 0; |
4583 | memset(fgd->table, 0, fgd->size * sizeof(*fgd->table)); | |
ea4e2bc4 | 4584 | } |
a4ec5e0c | 4585 | mutex_unlock(&graph_lock); |
ea4e2bc4 | 4586 | |
faf982a6 NK |
4587 | if (file->f_mode & FMODE_READ) { |
4588 | ret = seq_open(file, fgd->seq_ops); | |
4589 | if (!ret) { | |
4590 | struct seq_file *m = file->private_data; | |
4591 | m->private = fgd; | |
4592 | } | |
4593 | } else | |
4594 | file->private_data = fgd; | |
ea4e2bc4 SR |
4595 | |
4596 | return ret; | |
4597 | } | |
4598 | ||
faf982a6 NK |
4599 | static int |
4600 | ftrace_graph_open(struct inode *inode, struct file *file) | |
4601 | { | |
4602 | struct ftrace_graph_data *fgd; | |
4603 | ||
4604 | if (unlikely(ftrace_disabled)) | |
4605 | return -ENODEV; | |
4606 | ||
4607 | fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); | |
4608 | if (fgd == NULL) | |
4609 | return -ENOMEM; | |
4610 | ||
4611 | fgd->table = ftrace_graph_funcs; | |
4612 | fgd->size = FTRACE_GRAPH_MAX_FUNCS; | |
4613 | fgd->count = &ftrace_graph_count; | |
4614 | fgd->seq_ops = &ftrace_graph_seq_ops; | |
4615 | ||
4616 | return __ftrace_graph_open(inode, file, fgd); | |
4617 | } | |
4618 | ||
29ad23b0 NK |
4619 | static int |
4620 | ftrace_graph_notrace_open(struct inode *inode, struct file *file) | |
4621 | { | |
4622 | struct ftrace_graph_data *fgd; | |
4623 | ||
4624 | if (unlikely(ftrace_disabled)) | |
4625 | return -ENODEV; | |
4626 | ||
4627 | fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); | |
4628 | if (fgd == NULL) | |
4629 | return -ENOMEM; | |
4630 | ||
4631 | fgd->table = ftrace_graph_notrace_funcs; | |
4632 | fgd->size = FTRACE_GRAPH_MAX_FUNCS; | |
4633 | fgd->count = &ftrace_graph_notrace_count; | |
4634 | fgd->seq_ops = &ftrace_graph_seq_ops; | |
4635 | ||
4636 | return __ftrace_graph_open(inode, file, fgd); | |
4637 | } | |
4638 | ||
87827111 LZ |
4639 | static int |
4640 | ftrace_graph_release(struct inode *inode, struct file *file) | |
4641 | { | |
faf982a6 NK |
4642 | if (file->f_mode & FMODE_READ) { |
4643 | struct seq_file *m = file->private_data; | |
4644 | ||
4645 | kfree(m->private); | |
87827111 | 4646 | seq_release(inode, file); |
faf982a6 NK |
4647 | } else { |
4648 | kfree(file->private_data); | |
4649 | } | |
4650 | ||
87827111 LZ |
4651 | return 0; |
4652 | } | |
4653 | ||
ea4e2bc4 | 4654 | static int |
faf982a6 | 4655 | ftrace_set_func(unsigned long *array, int *idx, int size, char *buffer) |
ea4e2bc4 | 4656 | { |
3ba00929 | 4657 | struct ftrace_glob func_g; |
ea4e2bc4 SR |
4658 | struct dyn_ftrace *rec; |
4659 | struct ftrace_page *pg; | |
c7c6b1fe | 4660 | int fail = 1; |
3ba00929 | 4661 | int not; |
f9349a8f FW |
4662 | bool exists; |
4663 | int i; | |
ea4e2bc4 | 4664 | |
f9349a8f | 4665 | /* decode regex */ |
3ba00929 DS |
4666 | func_g.type = filter_parse_regex(buffer, strlen(buffer), |
4667 | &func_g.search, ¬); | |
faf982a6 | 4668 | if (!not && *idx >= size) |
c7c6b1fe | 4669 | return -EBUSY; |
f9349a8f | 4670 | |
3ba00929 | 4671 | func_g.len = strlen(func_g.search); |
f9349a8f | 4672 | |
52baf119 | 4673 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
4674 | |
4675 | if (unlikely(ftrace_disabled)) { | |
4676 | mutex_unlock(&ftrace_lock); | |
4677 | return -ENODEV; | |
4678 | } | |
4679 | ||
265c831c SR |
4680 | do_for_each_ftrace_rec(pg, rec) { |
4681 | ||
0b507e1e | 4682 | if (ftrace_match_record(rec, &func_g, NULL, 0)) { |
c7c6b1fe | 4683 | /* if it is in the array */ |
f9349a8f | 4684 | exists = false; |
c7c6b1fe | 4685 | for (i = 0; i < *idx; i++) { |
f9349a8f FW |
4686 | if (array[i] == rec->ip) { |
4687 | exists = true; | |
265c831c SR |
4688 | break; |
4689 | } | |
c7c6b1fe LZ |
4690 | } |
4691 | ||
4692 | if (!not) { | |
4693 | fail = 0; | |
4694 | if (!exists) { | |
4695 | array[(*idx)++] = rec->ip; | |
faf982a6 | 4696 | if (*idx >= size) |
c7c6b1fe LZ |
4697 | goto out; |
4698 | } | |
4699 | } else { | |
4700 | if (exists) { | |
4701 | array[i] = array[--(*idx)]; | |
4702 | array[*idx] = 0; | |
4703 | fail = 0; | |
4704 | } | |
4705 | } | |
ea4e2bc4 | 4706 | } |
265c831c | 4707 | } while_for_each_ftrace_rec(); |
c7c6b1fe | 4708 | out: |
52baf119 | 4709 | mutex_unlock(&ftrace_lock); |
ea4e2bc4 | 4710 | |
c7c6b1fe LZ |
4711 | if (fail) |
4712 | return -EINVAL; | |
4713 | ||
c7c6b1fe | 4714 | return 0; |
ea4e2bc4 SR |
4715 | } |
4716 | ||
4717 | static ssize_t | |
4718 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
4719 | size_t cnt, loff_t *ppos) | |
4720 | { | |
689fd8b6 | 4721 | struct trace_parser parser; |
6a10108b | 4722 | ssize_t read, ret = 0; |
faf982a6 | 4723 | struct ftrace_graph_data *fgd = file->private_data; |
ea4e2bc4 | 4724 | |
c7c6b1fe | 4725 | if (!cnt) |
ea4e2bc4 SR |
4726 | return 0; |
4727 | ||
6a10108b NK |
4728 | if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) |
4729 | return -ENOMEM; | |
ea4e2bc4 | 4730 | |
689fd8b6 | 4731 | read = trace_get_user(&parser, ubuf, cnt, ppos); |
ea4e2bc4 | 4732 | |
4ba7978e | 4733 | if (read >= 0 && trace_parser_loaded((&parser))) { |
689fd8b6 | 4734 | parser.buffer[parser.idx] = 0; |
4735 | ||
6a10108b NK |
4736 | mutex_lock(&graph_lock); |
4737 | ||
689fd8b6 | 4738 | /* we allow only one expression at a time */ |
faf982a6 NK |
4739 | ret = ftrace_set_func(fgd->table, fgd->count, fgd->size, |
4740 | parser.buffer); | |
6a10108b NK |
4741 | |
4742 | mutex_unlock(&graph_lock); | |
ea4e2bc4 | 4743 | } |
ea4e2bc4 | 4744 | |
6a10108b NK |
4745 | if (!ret) |
4746 | ret = read; | |
1eb90f13 | 4747 | |
689fd8b6 | 4748 | trace_parser_put(&parser); |
ea4e2bc4 SR |
4749 | |
4750 | return ret; | |
4751 | } | |
4752 | ||
4753 | static const struct file_operations ftrace_graph_fops = { | |
87827111 LZ |
4754 | .open = ftrace_graph_open, |
4755 | .read = seq_read, | |
4756 | .write = ftrace_graph_write, | |
098c879e | 4757 | .llseek = tracing_lseek, |
87827111 | 4758 | .release = ftrace_graph_release, |
ea4e2bc4 | 4759 | }; |
29ad23b0 NK |
4760 | |
4761 | static const struct file_operations ftrace_graph_notrace_fops = { | |
4762 | .open = ftrace_graph_notrace_open, | |
4763 | .read = seq_read, | |
4764 | .write = ftrace_graph_write, | |
098c879e | 4765 | .llseek = tracing_lseek, |
29ad23b0 NK |
4766 | .release = ftrace_graph_release, |
4767 | }; | |
ea4e2bc4 SR |
4768 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
4769 | ||
591dffda SRRH |
4770 | void ftrace_create_filter_files(struct ftrace_ops *ops, |
4771 | struct dentry *parent) | |
4772 | { | |
4773 | ||
4774 | trace_create_file("set_ftrace_filter", 0644, parent, | |
4775 | ops, &ftrace_filter_fops); | |
4776 | ||
4777 | trace_create_file("set_ftrace_notrace", 0644, parent, | |
4778 | ops, &ftrace_notrace_fops); | |
4779 | } | |
4780 | ||
4781 | /* | |
4782 | * The name "destroy_filter_files" is really a misnomer. Although | |
4783 | * in the future, it may actualy delete the files, but this is | |
4784 | * really intended to make sure the ops passed in are disabled | |
4785 | * and that when this function returns, the caller is free to | |
4786 | * free the ops. | |
4787 | * | |
4788 | * The "destroy" name is only to match the "create" name that this | |
4789 | * should be paired with. | |
4790 | */ | |
4791 | void ftrace_destroy_filter_files(struct ftrace_ops *ops) | |
4792 | { | |
4793 | mutex_lock(&ftrace_lock); | |
4794 | if (ops->flags & FTRACE_OPS_FL_ENABLED) | |
4795 | ftrace_shutdown(ops, 0); | |
4796 | ops->flags |= FTRACE_OPS_FL_DELETED; | |
4797 | mutex_unlock(&ftrace_lock); | |
4798 | } | |
4799 | ||
8434dc93 | 4800 | static __init int ftrace_init_dyn_tracefs(struct dentry *d_tracer) |
5072c59f | 4801 | { |
5072c59f | 4802 | |
5452af66 FW |
4803 | trace_create_file("available_filter_functions", 0444, |
4804 | d_tracer, NULL, &ftrace_avail_fops); | |
5072c59f | 4805 | |
647bcd03 SR |
4806 | trace_create_file("enabled_functions", 0444, |
4807 | d_tracer, NULL, &ftrace_enabled_fops); | |
4808 | ||
591dffda | 4809 | ftrace_create_filter_files(&global_ops, d_tracer); |
ad90c0e3 | 4810 | |
ea4e2bc4 | 4811 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5452af66 | 4812 | trace_create_file("set_graph_function", 0444, d_tracer, |
ea4e2bc4 SR |
4813 | NULL, |
4814 | &ftrace_graph_fops); | |
29ad23b0 NK |
4815 | trace_create_file("set_graph_notrace", 0444, d_tracer, |
4816 | NULL, | |
4817 | &ftrace_graph_notrace_fops); | |
ea4e2bc4 SR |
4818 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
4819 | ||
5072c59f SR |
4820 | return 0; |
4821 | } | |
4822 | ||
9fd49328 | 4823 | static int ftrace_cmp_ips(const void *a, const void *b) |
68950619 | 4824 | { |
9fd49328 SR |
4825 | const unsigned long *ipa = a; |
4826 | const unsigned long *ipb = b; | |
68950619 | 4827 | |
9fd49328 SR |
4828 | if (*ipa > *ipb) |
4829 | return 1; | |
4830 | if (*ipa < *ipb) | |
4831 | return -1; | |
4832 | return 0; | |
4833 | } | |
4834 | ||
5cb084bb | 4835 | static int ftrace_process_locs(struct module *mod, |
31e88909 | 4836 | unsigned long *start, |
68bf21aa SR |
4837 | unsigned long *end) |
4838 | { | |
706c81f8 | 4839 | struct ftrace_page *start_pg; |
a7900875 | 4840 | struct ftrace_page *pg; |
706c81f8 | 4841 | struct dyn_ftrace *rec; |
a7900875 | 4842 | unsigned long count; |
68bf21aa SR |
4843 | unsigned long *p; |
4844 | unsigned long addr; | |
4376cac6 | 4845 | unsigned long flags = 0; /* Shut up gcc */ |
a7900875 SR |
4846 | int ret = -ENOMEM; |
4847 | ||
4848 | count = end - start; | |
4849 | ||
4850 | if (!count) | |
4851 | return 0; | |
4852 | ||
9fd49328 | 4853 | sort(start, count, sizeof(*start), |
6db02903 | 4854 | ftrace_cmp_ips, NULL); |
9fd49328 | 4855 | |
706c81f8 SR |
4856 | start_pg = ftrace_allocate_pages(count); |
4857 | if (!start_pg) | |
a7900875 | 4858 | return -ENOMEM; |
68bf21aa | 4859 | |
e6ea44e9 | 4860 | mutex_lock(&ftrace_lock); |
a7900875 | 4861 | |
32082309 SR |
4862 | /* |
4863 | * Core and each module needs their own pages, as | |
4864 | * modules will free them when they are removed. | |
4865 | * Force a new page to be allocated for modules. | |
4866 | */ | |
a7900875 SR |
4867 | if (!mod) { |
4868 | WARN_ON(ftrace_pages || ftrace_pages_start); | |
4869 | /* First initialization */ | |
706c81f8 | 4870 | ftrace_pages = ftrace_pages_start = start_pg; |
a7900875 | 4871 | } else { |
32082309 | 4872 | if (!ftrace_pages) |
a7900875 | 4873 | goto out; |
32082309 | 4874 | |
a7900875 SR |
4875 | if (WARN_ON(ftrace_pages->next)) { |
4876 | /* Hmm, we have free pages? */ | |
4877 | while (ftrace_pages->next) | |
4878 | ftrace_pages = ftrace_pages->next; | |
32082309 | 4879 | } |
a7900875 | 4880 | |
706c81f8 | 4881 | ftrace_pages->next = start_pg; |
32082309 SR |
4882 | } |
4883 | ||
68bf21aa | 4884 | p = start; |
706c81f8 | 4885 | pg = start_pg; |
68bf21aa SR |
4886 | while (p < end) { |
4887 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
4888 | /* |
4889 | * Some architecture linkers will pad between | |
4890 | * the different mcount_loc sections of different | |
4891 | * object files to satisfy alignments. | |
4892 | * Skip any NULL pointers. | |
4893 | */ | |
4894 | if (!addr) | |
4895 | continue; | |
706c81f8 SR |
4896 | |
4897 | if (pg->index == pg->size) { | |
4898 | /* We should have allocated enough */ | |
4899 | if (WARN_ON(!pg->next)) | |
4900 | break; | |
4901 | pg = pg->next; | |
4902 | } | |
4903 | ||
4904 | rec = &pg->records[pg->index++]; | |
4905 | rec->ip = addr; | |
68bf21aa SR |
4906 | } |
4907 | ||
706c81f8 SR |
4908 | /* We should have used all pages */ |
4909 | WARN_ON(pg->next); | |
4910 | ||
4911 | /* Assign the last page to ftrace_pages */ | |
4912 | ftrace_pages = pg; | |
4913 | ||
a4f18ed1 | 4914 | /* |
4376cac6 SR |
4915 | * We only need to disable interrupts on start up |
4916 | * because we are modifying code that an interrupt | |
4917 | * may execute, and the modification is not atomic. | |
4918 | * But for modules, nothing runs the code we modify | |
4919 | * until we are finished with it, and there's no | |
4920 | * reason to cause large interrupt latencies while we do it. | |
a4f18ed1 | 4921 | */ |
4376cac6 SR |
4922 | if (!mod) |
4923 | local_irq_save(flags); | |
1dc43cf0 | 4924 | ftrace_update_code(mod, start_pg); |
4376cac6 SR |
4925 | if (!mod) |
4926 | local_irq_restore(flags); | |
a7900875 SR |
4927 | ret = 0; |
4928 | out: | |
e6ea44e9 | 4929 | mutex_unlock(&ftrace_lock); |
68bf21aa | 4930 | |
a7900875 | 4931 | return ret; |
68bf21aa SR |
4932 | } |
4933 | ||
93eb677d | 4934 | #ifdef CONFIG_MODULES |
32082309 SR |
4935 | |
4936 | #define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next) | |
4937 | ||
b7ffffbb SRRH |
4938 | static int referenced_filters(struct dyn_ftrace *rec) |
4939 | { | |
4940 | struct ftrace_ops *ops; | |
4941 | int cnt = 0; | |
4942 | ||
4943 | for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) { | |
4944 | if (ops_references_rec(ops, rec)) | |
4945 | cnt++; | |
4946 | } | |
4947 | ||
4948 | return cnt; | |
4949 | } | |
4950 | ||
e7247a15 | 4951 | void ftrace_release_mod(struct module *mod) |
93eb677d SR |
4952 | { |
4953 | struct dyn_ftrace *rec; | |
32082309 | 4954 | struct ftrace_page **last_pg; |
93eb677d | 4955 | struct ftrace_page *pg; |
a7900875 | 4956 | int order; |
93eb677d | 4957 | |
45a4a237 SR |
4958 | mutex_lock(&ftrace_lock); |
4959 | ||
e7247a15 | 4960 | if (ftrace_disabled) |
45a4a237 | 4961 | goto out_unlock; |
93eb677d | 4962 | |
32082309 SR |
4963 | /* |
4964 | * Each module has its own ftrace_pages, remove | |
4965 | * them from the list. | |
4966 | */ | |
4967 | last_pg = &ftrace_pages_start; | |
4968 | for (pg = ftrace_pages_start; pg; pg = *last_pg) { | |
4969 | rec = &pg->records[0]; | |
e7247a15 | 4970 | if (within_module_core(rec->ip, mod)) { |
93eb677d | 4971 | /* |
32082309 SR |
4972 | * As core pages are first, the first |
4973 | * page should never be a module page. | |
93eb677d | 4974 | */ |
32082309 SR |
4975 | if (WARN_ON(pg == ftrace_pages_start)) |
4976 | goto out_unlock; | |
4977 | ||
4978 | /* Check if we are deleting the last page */ | |
4979 | if (pg == ftrace_pages) | |
4980 | ftrace_pages = next_to_ftrace_page(last_pg); | |
4981 | ||
4982 | *last_pg = pg->next; | |
a7900875 SR |
4983 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); |
4984 | free_pages((unsigned long)pg->records, order); | |
4985 | kfree(pg); | |
32082309 SR |
4986 | } else |
4987 | last_pg = &pg->next; | |
4988 | } | |
45a4a237 | 4989 | out_unlock: |
93eb677d SR |
4990 | mutex_unlock(&ftrace_lock); |
4991 | } | |
4992 | ||
7dcd182b | 4993 | void ftrace_module_enable(struct module *mod) |
b7ffffbb SRRH |
4994 | { |
4995 | struct dyn_ftrace *rec; | |
4996 | struct ftrace_page *pg; | |
4997 | ||
4998 | mutex_lock(&ftrace_lock); | |
4999 | ||
5000 | if (ftrace_disabled) | |
5001 | goto out_unlock; | |
5002 | ||
5003 | /* | |
5004 | * If the tracing is enabled, go ahead and enable the record. | |
5005 | * | |
5006 | * The reason not to enable the record immediatelly is the | |
5007 | * inherent check of ftrace_make_nop/ftrace_make_call for | |
5008 | * correct previous instructions. Making first the NOP | |
5009 | * conversion puts the module to the correct state, thus | |
5010 | * passing the ftrace_make_call check. | |
5011 | * | |
5012 | * We also delay this to after the module code already set the | |
5013 | * text to read-only, as we now need to set it back to read-write | |
5014 | * so that we can modify the text. | |
5015 | */ | |
5016 | if (ftrace_start_up) | |
5017 | ftrace_arch_code_modify_prepare(); | |
5018 | ||
5019 | do_for_each_ftrace_rec(pg, rec) { | |
5020 | int cnt; | |
5021 | /* | |
5022 | * do_for_each_ftrace_rec() is a double loop. | |
5023 | * module text shares the pg. If a record is | |
5024 | * not part of this module, then skip this pg, | |
5025 | * which the "break" will do. | |
5026 | */ | |
5027 | if (!within_module_core(rec->ip, mod)) | |
5028 | break; | |
5029 | ||
5030 | cnt = 0; | |
5031 | ||
5032 | /* | |
5033 | * When adding a module, we need to check if tracers are | |
5034 | * currently enabled and if they are, and can trace this record, | |
5035 | * we need to enable the module functions as well as update the | |
5036 | * reference counts for those function records. | |
5037 | */ | |
5038 | if (ftrace_start_up) | |
5039 | cnt += referenced_filters(rec); | |
5040 | ||
5041 | /* This clears FTRACE_FL_DISABLED */ | |
5042 | rec->flags = cnt; | |
5043 | ||
5044 | if (ftrace_start_up && cnt) { | |
5045 | int failed = __ftrace_replace_code(rec, 1); | |
5046 | if (failed) { | |
5047 | ftrace_bug(failed, rec); | |
5048 | goto out_loop; | |
5049 | } | |
5050 | } | |
5051 | ||
5052 | } while_for_each_ftrace_rec(); | |
5053 | ||
5054 | out_loop: | |
5055 | if (ftrace_start_up) | |
5056 | ftrace_arch_code_modify_post_process(); | |
5057 | ||
5058 | out_unlock: | |
5059 | mutex_unlock(&ftrace_lock); | |
5060 | } | |
5061 | ||
b6b71f66 | 5062 | void ftrace_module_init(struct module *mod) |
90d595fe | 5063 | { |
97e9b4fc | 5064 | if (ftrace_disabled || !mod->num_ftrace_callsites) |
fed1939c | 5065 | return; |
90d595fe | 5066 | |
97e9b4fc SRRH |
5067 | ftrace_process_locs(mod, mod->ftrace_callsites, |
5068 | mod->ftrace_callsites + mod->num_ftrace_callsites); | |
8c189ea6 | 5069 | } |
93eb677d SR |
5070 | #endif /* CONFIG_MODULES */ |
5071 | ||
68bf21aa SR |
5072 | void __init ftrace_init(void) |
5073 | { | |
1dc43cf0 JS |
5074 | extern unsigned long __start_mcount_loc[]; |
5075 | extern unsigned long __stop_mcount_loc[]; | |
3a36cb11 | 5076 | unsigned long count, flags; |
68bf21aa SR |
5077 | int ret; |
5078 | ||
68bf21aa | 5079 | local_irq_save(flags); |
3a36cb11 | 5080 | ret = ftrace_dyn_arch_init(); |
68bf21aa | 5081 | local_irq_restore(flags); |
af64a7cb | 5082 | if (ret) |
68bf21aa SR |
5083 | goto failed; |
5084 | ||
5085 | count = __stop_mcount_loc - __start_mcount_loc; | |
c867ccd8 JS |
5086 | if (!count) { |
5087 | pr_info("ftrace: No functions to be traced?\n"); | |
68bf21aa | 5088 | goto failed; |
c867ccd8 JS |
5089 | } |
5090 | ||
5091 | pr_info("ftrace: allocating %ld entries in %ld pages\n", | |
5092 | count, count / ENTRIES_PER_PAGE + 1); | |
68bf21aa SR |
5093 | |
5094 | last_ftrace_enabled = ftrace_enabled = 1; | |
5095 | ||
5cb084bb | 5096 | ret = ftrace_process_locs(NULL, |
31e88909 | 5097 | __start_mcount_loc, |
68bf21aa SR |
5098 | __stop_mcount_loc); |
5099 | ||
2af15d6a SR |
5100 | set_ftrace_early_filters(); |
5101 | ||
68bf21aa SR |
5102 | return; |
5103 | failed: | |
5104 | ftrace_disabled = 1; | |
5105 | } | |
68bf21aa | 5106 | |
f3bea491 SRRH |
5107 | /* Do nothing if arch does not support this */ |
5108 | void __weak arch_ftrace_update_trampoline(struct ftrace_ops *ops) | |
5109 | { | |
5110 | } | |
5111 | ||
5112 | static void ftrace_update_trampoline(struct ftrace_ops *ops) | |
5113 | { | |
12cce594 SRRH |
5114 | |
5115 | /* | |
5116 | * Currently there's no safe way to free a trampoline when the kernel | |
5117 | * is configured with PREEMPT. That is because a task could be preempted | |
5118 | * when it jumped to the trampoline, it may be preempted for a long time | |
5119 | * depending on the system load, and currently there's no way to know | |
5120 | * when it will be off the trampoline. If the trampoline is freed | |
5121 | * too early, when the task runs again, it will be executing on freed | |
5122 | * memory and crash. | |
5123 | */ | |
5124 | #ifdef CONFIG_PREEMPT | |
f3bea491 SRRH |
5125 | /* Currently, only non dynamic ops can have a trampoline */ |
5126 | if (ops->flags & FTRACE_OPS_FL_DYNAMIC) | |
5127 | return; | |
12cce594 | 5128 | #endif |
f3bea491 SRRH |
5129 | |
5130 | arch_ftrace_update_trampoline(ops); | |
5131 | } | |
5132 | ||
3d083395 | 5133 | #else |
0b6e4d56 | 5134 | |
2b499381 | 5135 | static struct ftrace_ops global_ops = { |
bd69c30b | 5136 | .func = ftrace_stub, |
e3eea140 SRRH |
5137 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | |
5138 | FTRACE_OPS_FL_INITIALIZED | | |
5139 | FTRACE_OPS_FL_PID, | |
bd69c30b SR |
5140 | }; |
5141 | ||
0b6e4d56 FW |
5142 | static int __init ftrace_nodyn_init(void) |
5143 | { | |
5144 | ftrace_enabled = 1; | |
5145 | return 0; | |
5146 | } | |
6f415672 | 5147 | core_initcall(ftrace_nodyn_init); |
0b6e4d56 | 5148 | |
8434dc93 | 5149 | static inline int ftrace_init_dyn_tracefs(struct dentry *d_tracer) { return 0; } |
df4fc315 | 5150 | static inline void ftrace_startup_enable(int command) { } |
e1effa01 | 5151 | static inline void ftrace_startup_all(int command) { } |
5a45cfe1 | 5152 | /* Keep as macros so we do not need to define the commands */ |
8a56d776 SRRH |
5153 | # define ftrace_startup(ops, command) \ |
5154 | ({ \ | |
5155 | int ___ret = __register_ftrace_function(ops); \ | |
5156 | if (!___ret) \ | |
5157 | (ops)->flags |= FTRACE_OPS_FL_ENABLED; \ | |
5158 | ___ret; \ | |
3b6cfdb1 | 5159 | }) |
1fcc1553 SRRH |
5160 | # define ftrace_shutdown(ops, command) \ |
5161 | ({ \ | |
5162 | int ___ret = __unregister_ftrace_function(ops); \ | |
5163 | if (!___ret) \ | |
5164 | (ops)->flags &= ~FTRACE_OPS_FL_ENABLED; \ | |
5165 | ___ret; \ | |
5166 | }) | |
8a56d776 | 5167 | |
c7aafc54 IM |
5168 | # define ftrace_startup_sysctl() do { } while (0) |
5169 | # define ftrace_shutdown_sysctl() do { } while (0) | |
b848914c SR |
5170 | |
5171 | static inline int | |
195a8afc | 5172 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs) |
b848914c SR |
5173 | { |
5174 | return 1; | |
5175 | } | |
5176 | ||
f3bea491 SRRH |
5177 | static void ftrace_update_trampoline(struct ftrace_ops *ops) |
5178 | { | |
5179 | } | |
5180 | ||
3d083395 SR |
5181 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
5182 | ||
4104d326 SRRH |
5183 | __init void ftrace_init_global_array_ops(struct trace_array *tr) |
5184 | { | |
5185 | tr->ops = &global_ops; | |
5186 | tr->ops->private = tr; | |
5187 | } | |
5188 | ||
5189 | void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func) | |
5190 | { | |
5191 | /* If we filter on pids, update to use the pid function */ | |
5192 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { | |
5193 | if (WARN_ON(tr->ops->func != ftrace_stub)) | |
5194 | printk("ftrace ops had %pS for function\n", | |
5195 | tr->ops->func); | |
4104d326 SRRH |
5196 | } |
5197 | tr->ops->func = func; | |
5198 | tr->ops->private = tr; | |
5199 | } | |
5200 | ||
5201 | void ftrace_reset_array_ops(struct trace_array *tr) | |
5202 | { | |
5203 | tr->ops->func = ftrace_stub; | |
5204 | } | |
5205 | ||
2f5f6ad9 SR |
5206 | static inline void |
5207 | __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 5208 | struct ftrace_ops *ignored, struct pt_regs *regs) |
b848914c | 5209 | { |
cdbe61bf | 5210 | struct ftrace_ops *op; |
edc15caf | 5211 | int bit; |
b848914c | 5212 | |
edc15caf SR |
5213 | bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); |
5214 | if (bit < 0) | |
5215 | return; | |
b1cff0ad | 5216 | |
cdbe61bf SR |
5217 | /* |
5218 | * Some of the ops may be dynamically allocated, | |
5219 | * they must be freed after a synchronize_sched(). | |
5220 | */ | |
5221 | preempt_disable_notrace(); | |
ba27f2bc | 5222 | |
0a016409 | 5223 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
ba27f2bc SRRH |
5224 | /* |
5225 | * Check the following for each ops before calling their func: | |
5226 | * if RCU flag is set, then rcu_is_watching() must be true | |
5227 | * if PER_CPU is set, then ftrace_function_local_disable() | |
5228 | * must be false | |
5229 | * Otherwise test if the ip matches the ops filter | |
5230 | * | |
5231 | * If any of the above fails then the op->func() is not executed. | |
5232 | */ | |
5233 | if ((!(op->flags & FTRACE_OPS_FL_RCU) || rcu_is_watching()) && | |
5234 | (!(op->flags & FTRACE_OPS_FL_PER_CPU) || | |
5235 | !ftrace_function_local_disabled(op)) && | |
5236 | ftrace_ops_test(op, ip, regs)) { | |
5237 | ||
1d48d596 SRRH |
5238 | if (FTRACE_WARN_ON(!op->func)) { |
5239 | pr_warn("op=%p %pS\n", op, op); | |
4104d326 SRRH |
5240 | goto out; |
5241 | } | |
a1e2e31d | 5242 | op->func(ip, parent_ip, op, regs); |
4104d326 | 5243 | } |
0a016409 | 5244 | } while_for_each_ftrace_op(op); |
4104d326 | 5245 | out: |
cdbe61bf | 5246 | preempt_enable_notrace(); |
edc15caf | 5247 | trace_clear_recursion(bit); |
b848914c SR |
5248 | } |
5249 | ||
2f5f6ad9 SR |
5250 | /* |
5251 | * Some archs only support passing ip and parent_ip. Even though | |
5252 | * the list function ignores the op parameter, we do not want any | |
5253 | * C side effects, where a function is called without the caller | |
5254 | * sending a third parameter. | |
a1e2e31d SR |
5255 | * Archs are to support both the regs and ftrace_ops at the same time. |
5256 | * If they support ftrace_ops, it is assumed they support regs. | |
5257 | * If call backs want to use regs, they must either check for regs | |
06aeaaea MH |
5258 | * being NULL, or CONFIG_DYNAMIC_FTRACE_WITH_REGS. |
5259 | * Note, CONFIG_DYNAMIC_FTRACE_WITH_REGS expects a full regs to be saved. | |
a1e2e31d | 5260 | * An architecture can pass partial regs with ftrace_ops and still |
b8ec330a | 5261 | * set the ARCH_SUPPORTS_FTRACE_OPS. |
2f5f6ad9 SR |
5262 | */ |
5263 | #if ARCH_SUPPORTS_FTRACE_OPS | |
5264 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 5265 | struct ftrace_ops *op, struct pt_regs *regs) |
2f5f6ad9 | 5266 | { |
a1e2e31d | 5267 | __ftrace_ops_list_func(ip, parent_ip, NULL, regs); |
2f5f6ad9 SR |
5268 | } |
5269 | #else | |
5270 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip) | |
5271 | { | |
a1e2e31d | 5272 | __ftrace_ops_list_func(ip, parent_ip, NULL, NULL); |
2f5f6ad9 SR |
5273 | } |
5274 | #endif | |
5275 | ||
f1ff6348 SRRH |
5276 | /* |
5277 | * If there's only one function registered but it does not support | |
c68c0fa2 SRRH |
5278 | * recursion, needs RCU protection and/or requires per cpu handling, then |
5279 | * this function will be called by the mcount trampoline. | |
f1ff6348 | 5280 | */ |
c68c0fa2 | 5281 | static void ftrace_ops_assist_func(unsigned long ip, unsigned long parent_ip, |
f1ff6348 SRRH |
5282 | struct ftrace_ops *op, struct pt_regs *regs) |
5283 | { | |
5284 | int bit; | |
5285 | ||
c68c0fa2 SRRH |
5286 | if ((op->flags & FTRACE_OPS_FL_RCU) && !rcu_is_watching()) |
5287 | return; | |
5288 | ||
f1ff6348 SRRH |
5289 | bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); |
5290 | if (bit < 0) | |
5291 | return; | |
5292 | ||
c68c0fa2 | 5293 | preempt_disable_notrace(); |
f1ff6348 | 5294 | |
c68c0fa2 SRRH |
5295 | if (!(op->flags & FTRACE_OPS_FL_PER_CPU) || |
5296 | !ftrace_function_local_disabled(op)) { | |
5297 | op->func(ip, parent_ip, op, regs); | |
5298 | } | |
5299 | ||
5300 | preempt_enable_notrace(); | |
f1ff6348 SRRH |
5301 | trace_clear_recursion(bit); |
5302 | } | |
5303 | ||
87354059 SRRH |
5304 | /** |
5305 | * ftrace_ops_get_func - get the function a trampoline should call | |
5306 | * @ops: the ops to get the function for | |
5307 | * | |
5308 | * Normally the mcount trampoline will call the ops->func, but there | |
5309 | * are times that it should not. For example, if the ops does not | |
5310 | * have its own recursion protection, then it should call the | |
5311 | * ftrace_ops_recurs_func() instead. | |
5312 | * | |
5313 | * Returns the function that the trampoline should call for @ops. | |
5314 | */ | |
5315 | ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops) | |
5316 | { | |
87354059 | 5317 | /* |
c68c0fa2 SRRH |
5318 | * If the function does not handle recursion, needs to be RCU safe, |
5319 | * or does per cpu logic, then we need to call the assist handler. | |
87354059 | 5320 | */ |
c68c0fa2 SRRH |
5321 | if (!(ops->flags & FTRACE_OPS_FL_RECURSION_SAFE) || |
5322 | ops->flags & (FTRACE_OPS_FL_RCU | FTRACE_OPS_FL_PER_CPU)) | |
5323 | return ftrace_ops_assist_func; | |
87354059 SRRH |
5324 | |
5325 | return ops->func; | |
5326 | } | |
5327 | ||
345ddcc8 SRRH |
5328 | static void |
5329 | ftrace_filter_pid_sched_switch_probe(void *data, bool preempt, | |
5330 | struct task_struct *prev, struct task_struct *next) | |
978f3a45 | 5331 | { |
345ddcc8 SRRH |
5332 | struct trace_array *tr = data; |
5333 | struct trace_pid_list *pid_list; | |
978f3a45 | 5334 | |
345ddcc8 | 5335 | pid_list = rcu_dereference_sched(tr->function_pids); |
e32d8956 | 5336 | |
345ddcc8 SRRH |
5337 | this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid, |
5338 | trace_ignore_this_task(pid_list, next)); | |
978f3a45 SR |
5339 | } |
5340 | ||
345ddcc8 | 5341 | static void clear_ftrace_pids(struct trace_array *tr) |
e32d8956 | 5342 | { |
345ddcc8 SRRH |
5343 | struct trace_pid_list *pid_list; |
5344 | int cpu; | |
e32d8956 | 5345 | |
345ddcc8 SRRH |
5346 | pid_list = rcu_dereference_protected(tr->function_pids, |
5347 | lockdep_is_held(&ftrace_lock)); | |
5348 | if (!pid_list) | |
5349 | return; | |
229c4ef8 | 5350 | |
345ddcc8 | 5351 | unregister_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr); |
e32d8956 | 5352 | |
345ddcc8 SRRH |
5353 | for_each_possible_cpu(cpu) |
5354 | per_cpu_ptr(tr->trace_buffer.data, cpu)->ftrace_ignore_pid = false; | |
978f3a45 | 5355 | |
345ddcc8 | 5356 | rcu_assign_pointer(tr->function_pids, NULL); |
978f3a45 | 5357 | |
345ddcc8 SRRH |
5358 | /* Wait till all users are no longer using pid filtering */ |
5359 | synchronize_sched(); | |
e32d8956 | 5360 | |
345ddcc8 | 5361 | trace_free_pid_list(pid_list); |
e32d8956 SR |
5362 | } |
5363 | ||
345ddcc8 | 5364 | static void ftrace_pid_reset(struct trace_array *tr) |
df4fc315 | 5365 | { |
756d17ee | 5366 | mutex_lock(&ftrace_lock); |
345ddcc8 | 5367 | clear_ftrace_pids(tr); |
978f3a45 | 5368 | |
756d17ee | 5369 | ftrace_update_pid_func(); |
e1effa01 | 5370 | ftrace_startup_all(0); |
756d17ee | 5371 | |
5372 | mutex_unlock(&ftrace_lock); | |
756d17ee | 5373 | } |
5374 | ||
345ddcc8 SRRH |
5375 | /* Greater than any max PID */ |
5376 | #define FTRACE_NO_PIDS (void *)(PID_MAX_LIMIT + 1) | |
df4fc315 | 5377 | |
756d17ee | 5378 | static void *fpid_start(struct seq_file *m, loff_t *pos) |
345ddcc8 | 5379 | __acquires(RCU) |
756d17ee | 5380 | { |
345ddcc8 SRRH |
5381 | struct trace_pid_list *pid_list; |
5382 | struct trace_array *tr = m->private; | |
5383 | ||
756d17ee | 5384 | mutex_lock(&ftrace_lock); |
345ddcc8 SRRH |
5385 | rcu_read_lock_sched(); |
5386 | ||
5387 | pid_list = rcu_dereference_sched(tr->function_pids); | |
756d17ee | 5388 | |
345ddcc8 SRRH |
5389 | if (!pid_list) |
5390 | return !(*pos) ? FTRACE_NO_PIDS : NULL; | |
756d17ee | 5391 | |
345ddcc8 | 5392 | return trace_pid_start(pid_list, pos); |
756d17ee | 5393 | } |
5394 | ||
5395 | static void *fpid_next(struct seq_file *m, void *v, loff_t *pos) | |
5396 | { | |
345ddcc8 SRRH |
5397 | struct trace_array *tr = m->private; |
5398 | struct trace_pid_list *pid_list = rcu_dereference_sched(tr->function_pids); | |
5399 | ||
5400 | if (v == FTRACE_NO_PIDS) | |
756d17ee | 5401 | return NULL; |
5402 | ||
345ddcc8 | 5403 | return trace_pid_next(pid_list, v, pos); |
756d17ee | 5404 | } |
5405 | ||
5406 | static void fpid_stop(struct seq_file *m, void *p) | |
345ddcc8 | 5407 | __releases(RCU) |
756d17ee | 5408 | { |
345ddcc8 | 5409 | rcu_read_unlock_sched(); |
756d17ee | 5410 | mutex_unlock(&ftrace_lock); |
5411 | } | |
5412 | ||
5413 | static int fpid_show(struct seq_file *m, void *v) | |
5414 | { | |
345ddcc8 | 5415 | if (v == FTRACE_NO_PIDS) { |
fa6f0cc7 | 5416 | seq_puts(m, "no pid\n"); |
756d17ee | 5417 | return 0; |
5418 | } | |
5419 | ||
345ddcc8 | 5420 | return trace_pid_show(m, v); |
756d17ee | 5421 | } |
5422 | ||
5423 | static const struct seq_operations ftrace_pid_sops = { | |
5424 | .start = fpid_start, | |
5425 | .next = fpid_next, | |
5426 | .stop = fpid_stop, | |
5427 | .show = fpid_show, | |
5428 | }; | |
5429 | ||
5430 | static int | |
5431 | ftrace_pid_open(struct inode *inode, struct file *file) | |
5432 | { | |
345ddcc8 SRRH |
5433 | struct trace_array *tr = inode->i_private; |
5434 | struct seq_file *m; | |
756d17ee | 5435 | int ret = 0; |
5436 | ||
345ddcc8 SRRH |
5437 | if (trace_array_get(tr) < 0) |
5438 | return -ENODEV; | |
5439 | ||
756d17ee | 5440 | if ((file->f_mode & FMODE_WRITE) && |
5441 | (file->f_flags & O_TRUNC)) | |
345ddcc8 | 5442 | ftrace_pid_reset(tr); |
756d17ee | 5443 | |
345ddcc8 SRRH |
5444 | ret = seq_open(file, &ftrace_pid_sops); |
5445 | if (ret < 0) { | |
5446 | trace_array_put(tr); | |
5447 | } else { | |
5448 | m = file->private_data; | |
5449 | /* copy tr over to seq ops */ | |
5450 | m->private = tr; | |
5451 | } | |
756d17ee | 5452 | |
5453 | return ret; | |
5454 | } | |
5455 | ||
345ddcc8 SRRH |
5456 | static void ignore_task_cpu(void *data) |
5457 | { | |
5458 | struct trace_array *tr = data; | |
5459 | struct trace_pid_list *pid_list; | |
5460 | ||
5461 | /* | |
5462 | * This function is called by on_each_cpu() while the | |
5463 | * event_mutex is held. | |
5464 | */ | |
5465 | pid_list = rcu_dereference_protected(tr->function_pids, | |
5466 | mutex_is_locked(&ftrace_lock)); | |
5467 | ||
5468 | this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid, | |
5469 | trace_ignore_this_task(pid_list, current)); | |
5470 | } | |
5471 | ||
df4fc315 SR |
5472 | static ssize_t |
5473 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
5474 | size_t cnt, loff_t *ppos) | |
5475 | { | |
345ddcc8 SRRH |
5476 | struct seq_file *m = filp->private_data; |
5477 | struct trace_array *tr = m->private; | |
5478 | struct trace_pid_list *filtered_pids = NULL; | |
5479 | struct trace_pid_list *pid_list; | |
5480 | ssize_t ret; | |
df4fc315 | 5481 | |
345ddcc8 SRRH |
5482 | if (!cnt) |
5483 | return 0; | |
5484 | ||
5485 | mutex_lock(&ftrace_lock); | |
5486 | ||
5487 | filtered_pids = rcu_dereference_protected(tr->function_pids, | |
5488 | lockdep_is_held(&ftrace_lock)); | |
5489 | ||
5490 | ret = trace_pid_write(filtered_pids, &pid_list, ubuf, cnt); | |
5491 | if (ret < 0) | |
5492 | goto out; | |
df4fc315 | 5493 | |
345ddcc8 | 5494 | rcu_assign_pointer(tr->function_pids, pid_list); |
df4fc315 | 5495 | |
345ddcc8 SRRH |
5496 | if (filtered_pids) { |
5497 | synchronize_sched(); | |
5498 | trace_free_pid_list(filtered_pids); | |
5499 | } else if (pid_list) { | |
5500 | /* Register a probe to set whether to ignore the tracing of a task */ | |
5501 | register_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr); | |
5502 | } | |
df4fc315 | 5503 | |
756d17ee | 5504 | /* |
345ddcc8 SRRH |
5505 | * Ignoring of pids is done at task switch. But we have to |
5506 | * check for those tasks that are currently running. | |
5507 | * Always do this in case a pid was appended or removed. | |
756d17ee | 5508 | */ |
345ddcc8 | 5509 | on_each_cpu(ignore_task_cpu, tr, 1); |
756d17ee | 5510 | |
345ddcc8 SRRH |
5511 | ftrace_update_pid_func(); |
5512 | ftrace_startup_all(0); | |
5513 | out: | |
5514 | mutex_unlock(&ftrace_lock); | |
df4fc315 | 5515 | |
345ddcc8 SRRH |
5516 | if (ret > 0) |
5517 | *ppos += ret; | |
df4fc315 | 5518 | |
345ddcc8 | 5519 | return ret; |
756d17ee | 5520 | } |
df4fc315 | 5521 | |
756d17ee | 5522 | static int |
5523 | ftrace_pid_release(struct inode *inode, struct file *file) | |
5524 | { | |
345ddcc8 | 5525 | struct trace_array *tr = inode->i_private; |
df4fc315 | 5526 | |
345ddcc8 SRRH |
5527 | trace_array_put(tr); |
5528 | ||
5529 | return seq_release(inode, file); | |
df4fc315 SR |
5530 | } |
5531 | ||
5e2336a0 | 5532 | static const struct file_operations ftrace_pid_fops = { |
756d17ee | 5533 | .open = ftrace_pid_open, |
5534 | .write = ftrace_pid_write, | |
5535 | .read = seq_read, | |
098c879e | 5536 | .llseek = tracing_lseek, |
756d17ee | 5537 | .release = ftrace_pid_release, |
df4fc315 SR |
5538 | }; |
5539 | ||
345ddcc8 | 5540 | void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
df4fc315 | 5541 | { |
5452af66 | 5542 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
345ddcc8 | 5543 | tr, &ftrace_pid_fops); |
df4fc315 | 5544 | } |
df4fc315 | 5545 | |
501c2375 SRRH |
5546 | void __init ftrace_init_tracefs_toplevel(struct trace_array *tr, |
5547 | struct dentry *d_tracer) | |
5548 | { | |
5549 | /* Only the top level directory has the dyn_tracefs and profile */ | |
5550 | WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); | |
5551 | ||
5552 | ftrace_init_dyn_tracefs(d_tracer); | |
5553 | ftrace_profile_tracefs(d_tracer); | |
5554 | } | |
5555 | ||
a2bb6a3d | 5556 | /** |
81adbdc0 | 5557 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
5558 | * |
5559 | * This function should be used by panic code. It stops ftrace | |
5560 | * but in a not so nice way. If you need to simply kill ftrace | |
5561 | * from a non-atomic section, use ftrace_kill. | |
5562 | */ | |
81adbdc0 | 5563 | void ftrace_kill(void) |
a2bb6a3d SR |
5564 | { |
5565 | ftrace_disabled = 1; | |
5566 | ftrace_enabled = 0; | |
a2bb6a3d SR |
5567 | clear_ftrace_function(); |
5568 | } | |
5569 | ||
e0a413f6 SR |
5570 | /** |
5571 | * Test if ftrace is dead or not. | |
5572 | */ | |
5573 | int ftrace_is_dead(void) | |
5574 | { | |
5575 | return ftrace_disabled; | |
5576 | } | |
5577 | ||
16444a8a | 5578 | /** |
3d083395 SR |
5579 | * register_ftrace_function - register a function for profiling |
5580 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 5581 | * |
3d083395 SR |
5582 | * Register a function to be called by all functions in the |
5583 | * kernel. | |
5584 | * | |
5585 | * Note: @ops->func and all the functions it calls must be labeled | |
5586 | * with "notrace", otherwise it will go into a | |
5587 | * recursive loop. | |
16444a8a | 5588 | */ |
3d083395 | 5589 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 5590 | { |
45a4a237 | 5591 | int ret = -1; |
4eebcc81 | 5592 | |
f04f24fb MH |
5593 | ftrace_ops_init(ops); |
5594 | ||
e6ea44e9 | 5595 | mutex_lock(&ftrace_lock); |
e7d3737e | 5596 | |
8a56d776 | 5597 | ret = ftrace_startup(ops, 0); |
b848914c | 5598 | |
e6ea44e9 | 5599 | mutex_unlock(&ftrace_lock); |
8d240dd8 | 5600 | |
b0fc494f | 5601 | return ret; |
3d083395 | 5602 | } |
cdbe61bf | 5603 | EXPORT_SYMBOL_GPL(register_ftrace_function); |
3d083395 SR |
5604 | |
5605 | /** | |
32632920 | 5606 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
5607 | * @ops - ops structure that holds the function to unregister |
5608 | * | |
5609 | * Unregister a function that was added to be called by ftrace profiling. | |
5610 | */ | |
5611 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
5612 | { | |
5613 | int ret; | |
5614 | ||
e6ea44e9 | 5615 | mutex_lock(&ftrace_lock); |
8a56d776 | 5616 | ret = ftrace_shutdown(ops, 0); |
e6ea44e9 | 5617 | mutex_unlock(&ftrace_lock); |
b0fc494f SR |
5618 | |
5619 | return ret; | |
5620 | } | |
cdbe61bf | 5621 | EXPORT_SYMBOL_GPL(unregister_ftrace_function); |
b0fc494f | 5622 | |
e309b41d | 5623 | int |
b0fc494f | 5624 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
8d65af78 | 5625 | void __user *buffer, size_t *lenp, |
b0fc494f SR |
5626 | loff_t *ppos) |
5627 | { | |
45a4a237 | 5628 | int ret = -ENODEV; |
4eebcc81 | 5629 | |
e6ea44e9 | 5630 | mutex_lock(&ftrace_lock); |
b0fc494f | 5631 | |
45a4a237 SR |
5632 | if (unlikely(ftrace_disabled)) |
5633 | goto out; | |
5634 | ||
5635 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
b0fc494f | 5636 | |
a32c7765 | 5637 | if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) |
b0fc494f SR |
5638 | goto out; |
5639 | ||
a32c7765 | 5640 | last_ftrace_enabled = !!ftrace_enabled; |
b0fc494f SR |
5641 | |
5642 | if (ftrace_enabled) { | |
5643 | ||
b0fc494f | 5644 | /* we are starting ftrace again */ |
5000c418 JK |
5645 | if (ftrace_ops_list != &ftrace_list_end) |
5646 | update_ftrace_function(); | |
b0fc494f | 5647 | |
524a3868 SRRH |
5648 | ftrace_startup_sysctl(); |
5649 | ||
b0fc494f SR |
5650 | } else { |
5651 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
5652 | ftrace_trace_function = ftrace_stub; | |
5653 | ||
5654 | ftrace_shutdown_sysctl(); | |
5655 | } | |
5656 | ||
5657 | out: | |
e6ea44e9 | 5658 | mutex_unlock(&ftrace_lock); |
3d083395 | 5659 | return ret; |
16444a8a | 5660 | } |
f17845e5 | 5661 | |
fb52607a | 5662 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 5663 | |
5f151b24 SRRH |
5664 | static struct ftrace_ops graph_ops = { |
5665 | .func = ftrace_stub, | |
5666 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | | |
5667 | FTRACE_OPS_FL_INITIALIZED | | |
e3eea140 | 5668 | FTRACE_OPS_FL_PID | |
5f151b24 SRRH |
5669 | FTRACE_OPS_FL_STUB, |
5670 | #ifdef FTRACE_GRAPH_TRAMP_ADDR | |
5671 | .trampoline = FTRACE_GRAPH_TRAMP_ADDR, | |
aec0be2d | 5672 | /* trampoline_size is only needed for dynamically allocated tramps */ |
5f151b24 SRRH |
5673 | #endif |
5674 | ASSIGN_OPS_HASH(graph_ops, &global_ops.local_hash) | |
5675 | }; | |
5676 | ||
55577204 SRRH |
5677 | void ftrace_graph_sleep_time_control(bool enable) |
5678 | { | |
5679 | fgraph_sleep_time = enable; | |
5680 | } | |
5681 | ||
5682 | void ftrace_graph_graph_time_control(bool enable) | |
5683 | { | |
5684 | fgraph_graph_time = enable; | |
5685 | } | |
5686 | ||
e49dc19c SR |
5687 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
5688 | { | |
5689 | return 0; | |
5690 | } | |
5691 | ||
287b6e68 FW |
5692 | /* The callbacks that hook a function */ |
5693 | trace_func_graph_ret_t ftrace_graph_return = | |
5694 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 5695 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
23a8e844 | 5696 | static trace_func_graph_ent_t __ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
5697 | |
5698 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
5699 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
5700 | { | |
5701 | int i; | |
5702 | int ret = 0; | |
f201ae23 FW |
5703 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; |
5704 | struct task_struct *g, *t; | |
5705 | ||
5706 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
5707 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
5708 | * sizeof(struct ftrace_ret_stack), | |
5709 | GFP_KERNEL); | |
5710 | if (!ret_stack_list[i]) { | |
5711 | start = 0; | |
5712 | end = i; | |
5713 | ret = -ENOMEM; | |
5714 | goto free; | |
5715 | } | |
5716 | } | |
5717 | ||
6112a300 | 5718 | read_lock(&tasklist_lock); |
f201ae23 FW |
5719 | do_each_thread(g, t) { |
5720 | if (start == end) { | |
5721 | ret = -EAGAIN; | |
5722 | goto unlock; | |
5723 | } | |
5724 | ||
5725 | if (t->ret_stack == NULL) { | |
380c4b14 | 5726 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 | 5727 | atomic_set(&t->trace_overrun, 0); |
26c01624 SR |
5728 | t->curr_ret_stack = -1; |
5729 | /* Make sure the tasks see the -1 first: */ | |
5730 | smp_wmb(); | |
5731 | t->ret_stack = ret_stack_list[start++]; | |
f201ae23 FW |
5732 | } |
5733 | } while_each_thread(g, t); | |
5734 | ||
5735 | unlock: | |
6112a300 | 5736 | read_unlock(&tasklist_lock); |
f201ae23 FW |
5737 | free: |
5738 | for (i = start; i < end; i++) | |
5739 | kfree(ret_stack_list[i]); | |
5740 | return ret; | |
5741 | } | |
5742 | ||
8aef2d28 | 5743 | static void |
c73464b1 | 5744 | ftrace_graph_probe_sched_switch(void *ignore, bool preempt, |
38516ab5 | 5745 | struct task_struct *prev, struct task_struct *next) |
8aef2d28 SR |
5746 | { |
5747 | unsigned long long timestamp; | |
5748 | int index; | |
5749 | ||
be6f164a SR |
5750 | /* |
5751 | * Does the user want to count the time a function was asleep. | |
5752 | * If so, do not update the time stamps. | |
5753 | */ | |
55577204 | 5754 | if (fgraph_sleep_time) |
be6f164a SR |
5755 | return; |
5756 | ||
8aef2d28 SR |
5757 | timestamp = trace_clock_local(); |
5758 | ||
5759 | prev->ftrace_timestamp = timestamp; | |
5760 | ||
5761 | /* only process tasks that we timestamped */ | |
5762 | if (!next->ftrace_timestamp) | |
5763 | return; | |
5764 | ||
5765 | /* | |
5766 | * Update all the counters in next to make up for the | |
5767 | * time next was sleeping. | |
5768 | */ | |
5769 | timestamp -= next->ftrace_timestamp; | |
5770 | ||
5771 | for (index = next->curr_ret_stack; index >= 0; index--) | |
5772 | next->ret_stack[index].calltime += timestamp; | |
5773 | } | |
5774 | ||
f201ae23 | 5775 | /* Allocate a return stack for each task */ |
fb52607a | 5776 | static int start_graph_tracing(void) |
f201ae23 FW |
5777 | { |
5778 | struct ftrace_ret_stack **ret_stack_list; | |
5b058bcd | 5779 | int ret, cpu; |
f201ae23 FW |
5780 | |
5781 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
5782 | sizeof(struct ftrace_ret_stack *), | |
5783 | GFP_KERNEL); | |
5784 | ||
5785 | if (!ret_stack_list) | |
5786 | return -ENOMEM; | |
5787 | ||
5b058bcd | 5788 | /* The cpu_boot init_task->ret_stack will never be freed */ |
179c498a SR |
5789 | for_each_online_cpu(cpu) { |
5790 | if (!idle_task(cpu)->ret_stack) | |
868baf07 | 5791 | ftrace_graph_init_idle_task(idle_task(cpu), cpu); |
179c498a | 5792 | } |
5b058bcd | 5793 | |
f201ae23 FW |
5794 | do { |
5795 | ret = alloc_retstack_tasklist(ret_stack_list); | |
5796 | } while (ret == -EAGAIN); | |
5797 | ||
8aef2d28 | 5798 | if (!ret) { |
38516ab5 | 5799 | ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
8aef2d28 SR |
5800 | if (ret) |
5801 | pr_info("ftrace_graph: Couldn't activate tracepoint" | |
5802 | " probe to kernel_sched_switch\n"); | |
5803 | } | |
5804 | ||
f201ae23 FW |
5805 | kfree(ret_stack_list); |
5806 | return ret; | |
5807 | } | |
5808 | ||
4a2b8dda FW |
5809 | /* |
5810 | * Hibernation protection. | |
5811 | * The state of the current task is too much unstable during | |
5812 | * suspend/restore to disk. We want to protect against that. | |
5813 | */ | |
5814 | static int | |
5815 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, | |
5816 | void *unused) | |
5817 | { | |
5818 | switch (state) { | |
5819 | case PM_HIBERNATION_PREPARE: | |
5820 | pause_graph_tracing(); | |
5821 | break; | |
5822 | ||
5823 | case PM_POST_HIBERNATION: | |
5824 | unpause_graph_tracing(); | |
5825 | break; | |
5826 | } | |
5827 | return NOTIFY_DONE; | |
5828 | } | |
5829 | ||
23a8e844 SRRH |
5830 | static int ftrace_graph_entry_test(struct ftrace_graph_ent *trace) |
5831 | { | |
5832 | if (!ftrace_ops_test(&global_ops, trace->func, NULL)) | |
5833 | return 0; | |
5834 | return __ftrace_graph_entry(trace); | |
5835 | } | |
5836 | ||
5837 | /* | |
5838 | * The function graph tracer should only trace the functions defined | |
5839 | * by set_ftrace_filter and set_ftrace_notrace. If another function | |
5840 | * tracer ops is registered, the graph tracer requires testing the | |
5841 | * function against the global ops, and not just trace any function | |
5842 | * that any ftrace_ops registered. | |
5843 | */ | |
5844 | static void update_function_graph_func(void) | |
5845 | { | |
5f151b24 SRRH |
5846 | struct ftrace_ops *op; |
5847 | bool do_test = false; | |
5848 | ||
5849 | /* | |
5850 | * The graph and global ops share the same set of functions | |
5851 | * to test. If any other ops is on the list, then | |
5852 | * the graph tracing needs to test if its the function | |
5853 | * it should call. | |
5854 | */ | |
5855 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
5856 | if (op != &global_ops && op != &graph_ops && | |
5857 | op != &ftrace_list_end) { | |
5858 | do_test = true; | |
5859 | /* in double loop, break out with goto */ | |
5860 | goto out; | |
5861 | } | |
5862 | } while_for_each_ftrace_op(op); | |
5863 | out: | |
5864 | if (do_test) | |
23a8e844 | 5865 | ftrace_graph_entry = ftrace_graph_entry_test; |
5f151b24 SRRH |
5866 | else |
5867 | ftrace_graph_entry = __ftrace_graph_entry; | |
23a8e844 SRRH |
5868 | } |
5869 | ||
8275f69f MK |
5870 | static struct notifier_block ftrace_suspend_notifier = { |
5871 | .notifier_call = ftrace_suspend_notifier_call, | |
5872 | }; | |
5873 | ||
287b6e68 FW |
5874 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
5875 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 5876 | { |
e7d3737e FW |
5877 | int ret = 0; |
5878 | ||
e6ea44e9 | 5879 | mutex_lock(&ftrace_lock); |
e7d3737e | 5880 | |
05ce5818 | 5881 | /* we currently allow only one tracer registered at a time */ |
597af815 | 5882 | if (ftrace_graph_active) { |
05ce5818 SR |
5883 | ret = -EBUSY; |
5884 | goto out; | |
5885 | } | |
5886 | ||
4a2b8dda FW |
5887 | register_pm_notifier(&ftrace_suspend_notifier); |
5888 | ||
597af815 | 5889 | ftrace_graph_active++; |
fb52607a | 5890 | ret = start_graph_tracing(); |
f201ae23 | 5891 | if (ret) { |
597af815 | 5892 | ftrace_graph_active--; |
f201ae23 FW |
5893 | goto out; |
5894 | } | |
e53a6319 | 5895 | |
287b6e68 | 5896 | ftrace_graph_return = retfunc; |
23a8e844 SRRH |
5897 | |
5898 | /* | |
5899 | * Update the indirect function to the entryfunc, and the | |
5900 | * function that gets called to the entry_test first. Then | |
5901 | * call the update fgraph entry function to determine if | |
5902 | * the entryfunc should be called directly or not. | |
5903 | */ | |
5904 | __ftrace_graph_entry = entryfunc; | |
5905 | ftrace_graph_entry = ftrace_graph_entry_test; | |
5906 | update_function_graph_func(); | |
e53a6319 | 5907 | |
5f151b24 | 5908 | ret = ftrace_startup(&graph_ops, FTRACE_START_FUNC_RET); |
e7d3737e | 5909 | out: |
e6ea44e9 | 5910 | mutex_unlock(&ftrace_lock); |
e7d3737e | 5911 | return ret; |
15e6cb36 FW |
5912 | } |
5913 | ||
fb52607a | 5914 | void unregister_ftrace_graph(void) |
15e6cb36 | 5915 | { |
e6ea44e9 | 5916 | mutex_lock(&ftrace_lock); |
e7d3737e | 5917 | |
597af815 | 5918 | if (unlikely(!ftrace_graph_active)) |
2aad1b76 SR |
5919 | goto out; |
5920 | ||
597af815 | 5921 | ftrace_graph_active--; |
287b6e68 | 5922 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; |
e49dc19c | 5923 | ftrace_graph_entry = ftrace_graph_entry_stub; |
23a8e844 | 5924 | __ftrace_graph_entry = ftrace_graph_entry_stub; |
5f151b24 | 5925 | ftrace_shutdown(&graph_ops, FTRACE_STOP_FUNC_RET); |
4a2b8dda | 5926 | unregister_pm_notifier(&ftrace_suspend_notifier); |
38516ab5 | 5927 | unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
e7d3737e | 5928 | |
f3bea491 SRRH |
5929 | #ifdef CONFIG_DYNAMIC_FTRACE |
5930 | /* | |
5931 | * Function graph does not allocate the trampoline, but | |
5932 | * other global_ops do. We need to reset the ALLOC_TRAMP flag | |
5933 | * if one was used. | |
5934 | */ | |
5935 | global_ops.trampoline = save_global_trampoline; | |
5936 | if (save_global_flags & FTRACE_OPS_FL_ALLOC_TRAMP) | |
5937 | global_ops.flags |= FTRACE_OPS_FL_ALLOC_TRAMP; | |
5938 | #endif | |
5939 | ||
2aad1b76 | 5940 | out: |
e6ea44e9 | 5941 | mutex_unlock(&ftrace_lock); |
15e6cb36 | 5942 | } |
f201ae23 | 5943 | |
868baf07 SR |
5944 | static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack); |
5945 | ||
5946 | static void | |
5947 | graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack) | |
5948 | { | |
5949 | atomic_set(&t->tracing_graph_pause, 0); | |
5950 | atomic_set(&t->trace_overrun, 0); | |
5951 | t->ftrace_timestamp = 0; | |
25985edc | 5952 | /* make curr_ret_stack visible before we add the ret_stack */ |
868baf07 SR |
5953 | smp_wmb(); |
5954 | t->ret_stack = ret_stack; | |
5955 | } | |
5956 | ||
5957 | /* | |
5958 | * Allocate a return stack for the idle task. May be the first | |
5959 | * time through, or it may be done by CPU hotplug online. | |
5960 | */ | |
5961 | void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) | |
5962 | { | |
5963 | t->curr_ret_stack = -1; | |
5964 | /* | |
5965 | * The idle task has no parent, it either has its own | |
5966 | * stack or no stack at all. | |
5967 | */ | |
5968 | if (t->ret_stack) | |
5969 | WARN_ON(t->ret_stack != per_cpu(idle_ret_stack, cpu)); | |
5970 | ||
5971 | if (ftrace_graph_active) { | |
5972 | struct ftrace_ret_stack *ret_stack; | |
5973 | ||
5974 | ret_stack = per_cpu(idle_ret_stack, cpu); | |
5975 | if (!ret_stack) { | |
5976 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
5977 | * sizeof(struct ftrace_ret_stack), | |
5978 | GFP_KERNEL); | |
5979 | if (!ret_stack) | |
5980 | return; | |
5981 | per_cpu(idle_ret_stack, cpu) = ret_stack; | |
5982 | } | |
5983 | graph_init_task(t, ret_stack); | |
5984 | } | |
5985 | } | |
5986 | ||
f201ae23 | 5987 | /* Allocate a return stack for newly created task */ |
fb52607a | 5988 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 5989 | { |
84047e36 SR |
5990 | /* Make sure we do not use the parent ret_stack */ |
5991 | t->ret_stack = NULL; | |
ea14eb71 | 5992 | t->curr_ret_stack = -1; |
84047e36 | 5993 | |
597af815 | 5994 | if (ftrace_graph_active) { |
82310a32 SR |
5995 | struct ftrace_ret_stack *ret_stack; |
5996 | ||
5997 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
f201ae23 FW |
5998 | * sizeof(struct ftrace_ret_stack), |
5999 | GFP_KERNEL); | |
82310a32 | 6000 | if (!ret_stack) |
f201ae23 | 6001 | return; |
868baf07 | 6002 | graph_init_task(t, ret_stack); |
84047e36 | 6003 | } |
f201ae23 FW |
6004 | } |
6005 | ||
fb52607a | 6006 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 6007 | { |
eae849ca FW |
6008 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
6009 | ||
f201ae23 | 6010 | t->ret_stack = NULL; |
eae849ca FW |
6011 | /* NULL must become visible to IRQs before we free it: */ |
6012 | barrier(); | |
6013 | ||
6014 | kfree(ret_stack); | |
f201ae23 | 6015 | } |
15e6cb36 | 6016 | #endif |