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> |
5072c59f | 21 | #include <linux/debugfs.h> |
3d083395 | 22 | #include <linux/hardirq.h> |
2d8b820b | 23 | #include <linux/kthread.h> |
5072c59f | 24 | #include <linux/uaccess.h> |
5855fead | 25 | #include <linux/bsearch.h> |
56d82e00 | 26 | #include <linux/module.h> |
2d8b820b | 27 | #include <linux/ftrace.h> |
b0fc494f | 28 | #include <linux/sysctl.h> |
5a0e3ad6 | 29 | #include <linux/slab.h> |
5072c59f | 30 | #include <linux/ctype.h> |
68950619 | 31 | #include <linux/sort.h> |
3d083395 | 32 | #include <linux/list.h> |
59df055f | 33 | #include <linux/hash.h> |
3f379b03 | 34 | #include <linux/rcupdate.h> |
3d083395 | 35 | |
ad8d75ff | 36 | #include <trace/events/sched.h> |
8aef2d28 | 37 | |
2af15d6a | 38 | #include <asm/setup.h> |
395a59d0 | 39 | |
0706f1c4 | 40 | #include "trace_output.h" |
bac429f0 | 41 | #include "trace_stat.h" |
16444a8a | 42 | |
6912896e | 43 | #define FTRACE_WARN_ON(cond) \ |
0778d9ad SR |
44 | ({ \ |
45 | int ___r = cond; \ | |
46 | if (WARN_ON(___r)) \ | |
6912896e | 47 | ftrace_kill(); \ |
0778d9ad SR |
48 | ___r; \ |
49 | }) | |
6912896e SR |
50 | |
51 | #define FTRACE_WARN_ON_ONCE(cond) \ | |
0778d9ad SR |
52 | ({ \ |
53 | int ___r = cond; \ | |
54 | if (WARN_ON_ONCE(___r)) \ | |
6912896e | 55 | ftrace_kill(); \ |
0778d9ad SR |
56 | ___r; \ |
57 | }) | |
6912896e | 58 | |
8fc0c701 SR |
59 | /* hash bits for specific function selection */ |
60 | #define FTRACE_HASH_BITS 7 | |
61 | #define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS) | |
33dc9b12 SR |
62 | #define FTRACE_HASH_DEFAULT_BITS 10 |
63 | #define FTRACE_HASH_MAX_BITS 12 | |
8fc0c701 | 64 | |
e248491a JO |
65 | #define FL_GLOBAL_CONTROL_MASK (FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_CONTROL) |
66 | ||
f04f24fb MH |
67 | #ifdef CONFIG_DYNAMIC_FTRACE |
68 | #define INIT_REGEX_LOCK(opsname) \ | |
69 | .regex_lock = __MUTEX_INITIALIZER(opsname.regex_lock), | |
70 | #else | |
71 | #define INIT_REGEX_LOCK(opsname) | |
72 | #endif | |
73 | ||
2f5f6ad9 SR |
74 | static struct ftrace_ops ftrace_list_end __read_mostly = { |
75 | .func = ftrace_stub, | |
395b97a3 | 76 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_STUB, |
2f5f6ad9 SR |
77 | }; |
78 | ||
4eebcc81 SR |
79 | /* ftrace_enabled is a method to turn ftrace on or off */ |
80 | int ftrace_enabled __read_mostly; | |
d61f82d0 | 81 | static int last_ftrace_enabled; |
b0fc494f | 82 | |
60a7ecf4 | 83 | /* Quick disabling of function tracer. */ |
2f5f6ad9 SR |
84 | int function_trace_stop __read_mostly; |
85 | ||
86 | /* Current function tracing op */ | |
87 | struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end; | |
a0d0a2a5 SR |
88 | /* What to set function_trace_op to */ |
89 | static struct ftrace_ops *set_function_trace_op; | |
60a7ecf4 | 90 | |
756d17ee | 91 | /* List for set_ftrace_pid's pids. */ |
92 | LIST_HEAD(ftrace_pids); | |
93 | struct ftrace_pid { | |
94 | struct list_head list; | |
95 | struct pid *pid; | |
96 | }; | |
97 | ||
4eebcc81 SR |
98 | /* |
99 | * ftrace_disabled is set when an anomaly is discovered. | |
100 | * ftrace_disabled is much stronger than ftrace_enabled. | |
101 | */ | |
102 | static int ftrace_disabled __read_mostly; | |
103 | ||
52baf119 | 104 | static DEFINE_MUTEX(ftrace_lock); |
b0fc494f | 105 | |
b848914c | 106 | static struct ftrace_ops *ftrace_global_list __read_mostly = &ftrace_list_end; |
e248491a | 107 | static struct ftrace_ops *ftrace_control_list __read_mostly = &ftrace_list_end; |
b848914c | 108 | static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end; |
16444a8a | 109 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; |
df4fc315 | 110 | ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub; |
2b499381 | 111 | static struct ftrace_ops global_ops; |
e248491a | 112 | static struct ftrace_ops control_ops; |
16444a8a | 113 | |
2f5f6ad9 SR |
114 | #if ARCH_SUPPORTS_FTRACE_OPS |
115 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 116 | struct ftrace_ops *op, struct pt_regs *regs); |
2f5f6ad9 SR |
117 | #else |
118 | /* See comment below, where ftrace_ops_list_func is defined */ | |
119 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip); | |
120 | #define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops) | |
121 | #endif | |
b848914c | 122 | |
0a016409 SR |
123 | /* |
124 | * Traverse the ftrace_global_list, invoking all entries. The reason that we | |
1bb539ca | 125 | * can use rcu_dereference_raw_notrace() is that elements removed from this list |
0a016409 | 126 | * are simply leaked, so there is no need to interact with a grace-period |
1bb539ca | 127 | * mechanism. The rcu_dereference_raw_notrace() calls are needed to handle |
0a016409 SR |
128 | * concurrent insertions into the ftrace_global_list. |
129 | * | |
130 | * Silly Alpha and silly pointer-speculation compiler optimizations! | |
131 | */ | |
132 | #define do_for_each_ftrace_op(op, list) \ | |
1bb539ca | 133 | op = rcu_dereference_raw_notrace(list); \ |
0a016409 SR |
134 | do |
135 | ||
136 | /* | |
137 | * Optimized for just a single item in the list (as that is the normal case). | |
138 | */ | |
139 | #define while_for_each_ftrace_op(op) \ | |
1bb539ca | 140 | while (likely(op = rcu_dereference_raw_notrace((op)->next)) && \ |
0a016409 SR |
141 | unlikely((op) != &ftrace_list_end)) |
142 | ||
f04f24fb MH |
143 | static inline void ftrace_ops_init(struct ftrace_ops *ops) |
144 | { | |
145 | #ifdef CONFIG_DYNAMIC_FTRACE | |
146 | if (!(ops->flags & FTRACE_OPS_FL_INITIALIZED)) { | |
147 | mutex_init(&ops->regex_lock); | |
148 | ops->flags |= FTRACE_OPS_FL_INITIALIZED; | |
149 | } | |
150 | #endif | |
151 | } | |
152 | ||
ea701f11 SR |
153 | /** |
154 | * ftrace_nr_registered_ops - return number of ops registered | |
155 | * | |
156 | * Returns the number of ftrace_ops registered and tracing functions | |
157 | */ | |
158 | int ftrace_nr_registered_ops(void) | |
159 | { | |
160 | struct ftrace_ops *ops; | |
161 | int cnt = 0; | |
162 | ||
163 | mutex_lock(&ftrace_lock); | |
164 | ||
165 | for (ops = ftrace_ops_list; | |
166 | ops != &ftrace_list_end; ops = ops->next) | |
167 | cnt++; | |
168 | ||
169 | mutex_unlock(&ftrace_lock); | |
170 | ||
171 | return cnt; | |
172 | } | |
173 | ||
2f5f6ad9 SR |
174 | static void |
175 | ftrace_global_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 176 | struct ftrace_ops *op, struct pt_regs *regs) |
16444a8a | 177 | { |
c29f122c SR |
178 | int bit; |
179 | ||
edc15caf SR |
180 | bit = trace_test_and_set_recursion(TRACE_GLOBAL_START, TRACE_GLOBAL_MAX); |
181 | if (bit < 0) | |
b1cff0ad | 182 | return; |
16444a8a | 183 | |
0a016409 | 184 | do_for_each_ftrace_op(op, ftrace_global_list) { |
a1e2e31d | 185 | op->func(ip, parent_ip, op, regs); |
0a016409 | 186 | } while_for_each_ftrace_op(op); |
edc15caf SR |
187 | |
188 | trace_clear_recursion(bit); | |
16444a8a ACM |
189 | } |
190 | ||
2f5f6ad9 | 191 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 192 | struct ftrace_ops *op, struct pt_regs *regs) |
df4fc315 | 193 | { |
0ef8cde5 | 194 | if (!test_tsk_trace_trace(current)) |
df4fc315 SR |
195 | return; |
196 | ||
a1e2e31d | 197 | ftrace_pid_function(ip, parent_ip, op, regs); |
df4fc315 SR |
198 | } |
199 | ||
200 | static void set_ftrace_pid_function(ftrace_func_t func) | |
201 | { | |
202 | /* do not set ftrace_pid_function to itself! */ | |
203 | if (func != ftrace_pid_func) | |
204 | ftrace_pid_function = func; | |
205 | } | |
206 | ||
16444a8a | 207 | /** |
3d083395 | 208 | * clear_ftrace_function - reset the ftrace function |
16444a8a | 209 | * |
3d083395 SR |
210 | * This NULLs the ftrace function and in essence stops |
211 | * tracing. There may be lag | |
16444a8a | 212 | */ |
3d083395 | 213 | void clear_ftrace_function(void) |
16444a8a | 214 | { |
3d083395 | 215 | ftrace_trace_function = ftrace_stub; |
df4fc315 | 216 | ftrace_pid_function = ftrace_stub; |
3d083395 SR |
217 | } |
218 | ||
e248491a JO |
219 | static void control_ops_disable_all(struct ftrace_ops *ops) |
220 | { | |
221 | int cpu; | |
222 | ||
223 | for_each_possible_cpu(cpu) | |
224 | *per_cpu_ptr(ops->disabled, cpu) = 1; | |
225 | } | |
226 | ||
227 | static int control_ops_alloc(struct ftrace_ops *ops) | |
228 | { | |
229 | int __percpu *disabled; | |
230 | ||
231 | disabled = alloc_percpu(int); | |
232 | if (!disabled) | |
233 | return -ENOMEM; | |
234 | ||
235 | ops->disabled = disabled; | |
236 | control_ops_disable_all(ops); | |
237 | return 0; | |
238 | } | |
239 | ||
240 | static void control_ops_free(struct ftrace_ops *ops) | |
241 | { | |
242 | free_percpu(ops->disabled); | |
243 | } | |
244 | ||
2b499381 | 245 | static void update_global_ops(void) |
491d0dcf SR |
246 | { |
247 | ftrace_func_t func; | |
248 | ||
249 | /* | |
250 | * If there's only one function registered, then call that | |
251 | * function directly. Otherwise, we need to iterate over the | |
252 | * registered callers. | |
253 | */ | |
b848914c | 254 | if (ftrace_global_list == &ftrace_list_end || |
63503794 | 255 | ftrace_global_list->next == &ftrace_list_end) { |
b848914c | 256 | func = ftrace_global_list->func; |
63503794 SR |
257 | /* |
258 | * As we are calling the function directly. | |
259 | * If it does not have recursion protection, | |
260 | * the function_trace_op needs to be updated | |
261 | * accordingly. | |
262 | */ | |
263 | if (ftrace_global_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) | |
264 | global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE; | |
265 | else | |
266 | global_ops.flags &= ~FTRACE_OPS_FL_RECURSION_SAFE; | |
267 | } else { | |
b848914c | 268 | func = ftrace_global_list_func; |
63503794 SR |
269 | /* The list has its own recursion protection. */ |
270 | global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE; | |
271 | } | |
272 | ||
491d0dcf SR |
273 | |
274 | /* If we filter on pids, update to use the pid function */ | |
275 | if (!list_empty(&ftrace_pids)) { | |
276 | set_ftrace_pid_function(func); | |
277 | func = ftrace_pid_func; | |
278 | } | |
2b499381 SR |
279 | |
280 | global_ops.func = func; | |
281 | } | |
282 | ||
a0d0a2a5 SR |
283 | static void ftrace_sync(struct work_struct *work) |
284 | { | |
285 | /* | |
286 | * This function is just a stub to implement a hard force | |
287 | * of synchronize_sched(). This requires synchronizing | |
288 | * tasks even in userspace and idle. | |
289 | * | |
290 | * Yes, function tracing is rude. | |
291 | */ | |
292 | } | |
293 | ||
294 | static void ftrace_sync_ipi(void *data) | |
295 | { | |
296 | /* Probably not needed, but do it anyway */ | |
297 | smp_rmb(); | |
298 | } | |
299 | ||
1499a3eb SR |
300 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
301 | static void update_function_graph_func(void); | |
302 | #else | |
303 | static inline void update_function_graph_func(void) { } | |
304 | #endif | |
305 | ||
2b499381 SR |
306 | static void update_ftrace_function(void) |
307 | { | |
308 | ftrace_func_t func; | |
309 | ||
310 | update_global_ops(); | |
311 | ||
cdbe61bf SR |
312 | /* |
313 | * If we are at the end of the list and this ops is | |
4740974a SR |
314 | * recursion safe and not dynamic and the arch supports passing ops, |
315 | * then have the mcount trampoline call the function directly. | |
cdbe61bf | 316 | */ |
b848914c | 317 | if (ftrace_ops_list == &ftrace_list_end || |
cdbe61bf | 318 | (ftrace_ops_list->next == &ftrace_list_end && |
2f5f6ad9 | 319 | !(ftrace_ops_list->flags & FTRACE_OPS_FL_DYNAMIC) && |
4740974a | 320 | (ftrace_ops_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) && |
ccf3672d | 321 | !FTRACE_FORCE_LIST_FUNC)) { |
2f5f6ad9 SR |
322 | /* Set the ftrace_ops that the arch callback uses */ |
323 | if (ftrace_ops_list == &global_ops) | |
a0d0a2a5 | 324 | set_function_trace_op = ftrace_global_list; |
2f5f6ad9 | 325 | else |
a0d0a2a5 | 326 | set_function_trace_op = ftrace_ops_list; |
b848914c | 327 | func = ftrace_ops_list->func; |
2f5f6ad9 SR |
328 | } else { |
329 | /* Just use the default ftrace_ops */ | |
a0d0a2a5 | 330 | set_function_trace_op = &ftrace_list_end; |
b848914c | 331 | func = ftrace_ops_list_func; |
2f5f6ad9 | 332 | } |
2b499381 | 333 | |
9b87c4e5 SRRH |
334 | update_function_graph_func(); |
335 | ||
a0d0a2a5 SR |
336 | /* If there's no change, then do nothing more here */ |
337 | if (ftrace_trace_function == func) | |
338 | return; | |
339 | ||
340 | /* | |
341 | * If we are using the list function, it doesn't care | |
342 | * about the function_trace_ops. | |
343 | */ | |
344 | if (func == ftrace_ops_list_func) { | |
345 | ftrace_trace_function = func; | |
346 | /* | |
347 | * Don't even bother setting function_trace_ops, | |
348 | * it would be racy to do so anyway. | |
349 | */ | |
350 | return; | |
351 | } | |
352 | ||
353 | #ifndef CONFIG_DYNAMIC_FTRACE | |
354 | /* | |
355 | * For static tracing, we need to be a bit more careful. | |
356 | * The function change takes affect immediately. Thus, | |
357 | * we need to coorditate the setting of the function_trace_ops | |
358 | * with the setting of the ftrace_trace_function. | |
359 | * | |
360 | * Set the function to the list ops, which will call the | |
361 | * function we want, albeit indirectly, but it handles the | |
362 | * ftrace_ops and doesn't depend on function_trace_op. | |
363 | */ | |
364 | ftrace_trace_function = ftrace_ops_list_func; | |
365 | /* | |
366 | * Make sure all CPUs see this. Yes this is slow, but static | |
367 | * tracing is slow and nasty to have enabled. | |
368 | */ | |
369 | schedule_on_each_cpu(ftrace_sync); | |
370 | /* Now all cpus are using the list ops. */ | |
371 | function_trace_op = set_function_trace_op; | |
372 | /* Make sure the function_trace_op is visible on all CPUs */ | |
373 | smp_wmb(); | |
374 | /* Nasty way to force a rmb on all cpus */ | |
375 | smp_call_function(ftrace_sync_ipi, NULL, 1); | |
376 | /* OK, we are all set to update the ftrace_trace_function now! */ | |
377 | #endif /* !CONFIG_DYNAMIC_FTRACE */ | |
378 | ||
491d0dcf | 379 | ftrace_trace_function = func; |
491d0dcf SR |
380 | } |
381 | ||
2b499381 | 382 | static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
3d083395 | 383 | { |
2b499381 | 384 | ops->next = *list; |
16444a8a | 385 | /* |
b848914c | 386 | * We are entering ops into the list but another |
16444a8a ACM |
387 | * CPU might be walking that list. We need to make sure |
388 | * the ops->next pointer is valid before another CPU sees | |
b848914c | 389 | * the ops pointer included into the list. |
16444a8a | 390 | */ |
2b499381 | 391 | rcu_assign_pointer(*list, ops); |
16444a8a ACM |
392 | } |
393 | ||
2b499381 | 394 | static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
16444a8a | 395 | { |
16444a8a | 396 | struct ftrace_ops **p; |
16444a8a ACM |
397 | |
398 | /* | |
3d083395 SR |
399 | * If we are removing the last function, then simply point |
400 | * to the ftrace_stub. | |
16444a8a | 401 | */ |
2b499381 SR |
402 | if (*list == ops && ops->next == &ftrace_list_end) { |
403 | *list = &ftrace_list_end; | |
e6ea44e9 | 404 | return 0; |
16444a8a ACM |
405 | } |
406 | ||
2b499381 | 407 | for (p = list; *p != &ftrace_list_end; p = &(*p)->next) |
16444a8a ACM |
408 | if (*p == ops) |
409 | break; | |
410 | ||
e6ea44e9 SR |
411 | if (*p != ops) |
412 | return -1; | |
16444a8a ACM |
413 | |
414 | *p = (*p)->next; | |
2b499381 SR |
415 | return 0; |
416 | } | |
16444a8a | 417 | |
e248491a JO |
418 | static void add_ftrace_list_ops(struct ftrace_ops **list, |
419 | struct ftrace_ops *main_ops, | |
420 | struct ftrace_ops *ops) | |
421 | { | |
422 | int first = *list == &ftrace_list_end; | |
423 | add_ftrace_ops(list, ops); | |
424 | if (first) | |
425 | add_ftrace_ops(&ftrace_ops_list, main_ops); | |
426 | } | |
427 | ||
428 | static int remove_ftrace_list_ops(struct ftrace_ops **list, | |
429 | struct ftrace_ops *main_ops, | |
430 | struct ftrace_ops *ops) | |
431 | { | |
432 | int ret = remove_ftrace_ops(list, ops); | |
433 | if (!ret && *list == &ftrace_list_end) | |
434 | ret = remove_ftrace_ops(&ftrace_ops_list, main_ops); | |
435 | return ret; | |
436 | } | |
437 | ||
2b499381 SR |
438 | static int __register_ftrace_function(struct ftrace_ops *ops) |
439 | { | |
2b499381 SR |
440 | if (FTRACE_WARN_ON(ops == &global_ops)) |
441 | return -EINVAL; | |
442 | ||
b848914c SR |
443 | if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED)) |
444 | return -EBUSY; | |
445 | ||
e248491a JO |
446 | /* We don't support both control and global flags set. */ |
447 | if ((ops->flags & FL_GLOBAL_CONTROL_MASK) == FL_GLOBAL_CONTROL_MASK) | |
448 | return -EINVAL; | |
449 | ||
06aeaaea | 450 | #ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
08f6fba5 SR |
451 | /* |
452 | * If the ftrace_ops specifies SAVE_REGS, then it only can be used | |
453 | * if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set. | |
454 | * Setting SAVE_REGS_IF_SUPPORTED makes SAVE_REGS irrelevant. | |
455 | */ | |
456 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS && | |
457 | !(ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)) | |
458 | return -EINVAL; | |
459 | ||
460 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED) | |
461 | ops->flags |= FTRACE_OPS_FL_SAVE_REGS; | |
462 | #endif | |
463 | ||
cdbe61bf SR |
464 | if (!core_kernel_data((unsigned long)ops)) |
465 | ops->flags |= FTRACE_OPS_FL_DYNAMIC; | |
466 | ||
b848914c | 467 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
e248491a | 468 | add_ftrace_list_ops(&ftrace_global_list, &global_ops, ops); |
b848914c | 469 | ops->flags |= FTRACE_OPS_FL_ENABLED; |
e248491a JO |
470 | } else if (ops->flags & FTRACE_OPS_FL_CONTROL) { |
471 | if (control_ops_alloc(ops)) | |
472 | return -ENOMEM; | |
473 | add_ftrace_list_ops(&ftrace_control_list, &control_ops, ops); | |
b848914c SR |
474 | } else |
475 | add_ftrace_ops(&ftrace_ops_list, ops); | |
476 | ||
2b499381 SR |
477 | if (ftrace_enabled) |
478 | update_ftrace_function(); | |
479 | ||
480 | return 0; | |
481 | } | |
482 | ||
483 | static int __unregister_ftrace_function(struct ftrace_ops *ops) | |
484 | { | |
485 | int ret; | |
486 | ||
b848914c SR |
487 | if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) |
488 | return -EBUSY; | |
489 | ||
2b499381 SR |
490 | if (FTRACE_WARN_ON(ops == &global_ops)) |
491 | return -EINVAL; | |
492 | ||
b848914c | 493 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
e248491a JO |
494 | ret = remove_ftrace_list_ops(&ftrace_global_list, |
495 | &global_ops, ops); | |
b848914c SR |
496 | if (!ret) |
497 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; | |
e248491a JO |
498 | } else if (ops->flags & FTRACE_OPS_FL_CONTROL) { |
499 | ret = remove_ftrace_list_ops(&ftrace_control_list, | |
500 | &control_ops, ops); | |
b848914c SR |
501 | } else |
502 | ret = remove_ftrace_ops(&ftrace_ops_list, ops); | |
503 | ||
2b499381 SR |
504 | if (ret < 0) |
505 | return ret; | |
b848914c | 506 | |
491d0dcf SR |
507 | if (ftrace_enabled) |
508 | update_ftrace_function(); | |
16444a8a | 509 | |
e6ea44e9 | 510 | return 0; |
3d083395 SR |
511 | } |
512 | ||
df4fc315 SR |
513 | static void ftrace_update_pid_func(void) |
514 | { | |
491d0dcf | 515 | /* Only do something if we are tracing something */ |
df4fc315 | 516 | if (ftrace_trace_function == ftrace_stub) |
10dd3ebe | 517 | return; |
df4fc315 | 518 | |
491d0dcf | 519 | update_ftrace_function(); |
df4fc315 SR |
520 | } |
521 | ||
493762fc SR |
522 | #ifdef CONFIG_FUNCTION_PROFILER |
523 | struct ftrace_profile { | |
524 | struct hlist_node node; | |
525 | unsigned long ip; | |
526 | unsigned long counter; | |
0706f1c4 SR |
527 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
528 | unsigned long long time; | |
e330b3bc | 529 | unsigned long long time_squared; |
0706f1c4 | 530 | #endif |
8fc0c701 SR |
531 | }; |
532 | ||
493762fc SR |
533 | struct ftrace_profile_page { |
534 | struct ftrace_profile_page *next; | |
535 | unsigned long index; | |
536 | struct ftrace_profile records[]; | |
d61f82d0 SR |
537 | }; |
538 | ||
cafb168a SR |
539 | struct ftrace_profile_stat { |
540 | atomic_t disabled; | |
541 | struct hlist_head *hash; | |
542 | struct ftrace_profile_page *pages; | |
543 | struct ftrace_profile_page *start; | |
544 | struct tracer_stat stat; | |
545 | }; | |
546 | ||
493762fc SR |
547 | #define PROFILE_RECORDS_SIZE \ |
548 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | |
5072c59f | 549 | |
493762fc SR |
550 | #define PROFILES_PER_PAGE \ |
551 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | |
3d083395 | 552 | |
fb9fb015 SR |
553 | static int ftrace_profile_enabled __read_mostly; |
554 | ||
555 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ | |
bac429f0 SR |
556 | static DEFINE_MUTEX(ftrace_profile_lock); |
557 | ||
cafb168a | 558 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); |
493762fc | 559 | |
20079ebe NK |
560 | #define FTRACE_PROFILE_HASH_BITS 10 |
561 | #define FTRACE_PROFILE_HASH_SIZE (1 << FTRACE_PROFILE_HASH_BITS) | |
493762fc | 562 | |
bac429f0 SR |
563 | static void * |
564 | function_stat_next(void *v, int idx) | |
565 | { | |
493762fc SR |
566 | struct ftrace_profile *rec = v; |
567 | struct ftrace_profile_page *pg; | |
bac429f0 | 568 | |
493762fc | 569 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
bac429f0 SR |
570 | |
571 | again: | |
0296e425 LZ |
572 | if (idx != 0) |
573 | rec++; | |
574 | ||
bac429f0 SR |
575 | if ((void *)rec >= (void *)&pg->records[pg->index]) { |
576 | pg = pg->next; | |
577 | if (!pg) | |
578 | return NULL; | |
579 | rec = &pg->records[0]; | |
493762fc SR |
580 | if (!rec->counter) |
581 | goto again; | |
bac429f0 SR |
582 | } |
583 | ||
bac429f0 SR |
584 | return rec; |
585 | } | |
586 | ||
587 | static void *function_stat_start(struct tracer_stat *trace) | |
588 | { | |
cafb168a SR |
589 | struct ftrace_profile_stat *stat = |
590 | container_of(trace, struct ftrace_profile_stat, stat); | |
591 | ||
592 | if (!stat || !stat->start) | |
593 | return NULL; | |
594 | ||
595 | return function_stat_next(&stat->start->records[0], 0); | |
bac429f0 SR |
596 | } |
597 | ||
0706f1c4 SR |
598 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
599 | /* function graph compares on total time */ | |
600 | static int function_stat_cmp(void *p1, void *p2) | |
601 | { | |
602 | struct ftrace_profile *a = p1; | |
603 | struct ftrace_profile *b = p2; | |
604 | ||
605 | if (a->time < b->time) | |
606 | return -1; | |
607 | if (a->time > b->time) | |
608 | return 1; | |
609 | else | |
610 | return 0; | |
611 | } | |
612 | #else | |
613 | /* not function graph compares against hits */ | |
bac429f0 SR |
614 | static int function_stat_cmp(void *p1, void *p2) |
615 | { | |
493762fc SR |
616 | struct ftrace_profile *a = p1; |
617 | struct ftrace_profile *b = p2; | |
bac429f0 SR |
618 | |
619 | if (a->counter < b->counter) | |
620 | return -1; | |
621 | if (a->counter > b->counter) | |
622 | return 1; | |
623 | else | |
624 | return 0; | |
625 | } | |
0706f1c4 | 626 | #endif |
bac429f0 SR |
627 | |
628 | static int function_stat_headers(struct seq_file *m) | |
629 | { | |
0706f1c4 | 630 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b | 631 | seq_printf(m, " Function " |
e330b3bc | 632 | "Hit Time Avg s^2\n" |
34886c8b | 633 | " -------- " |
e330b3bc | 634 | "--- ---- --- ---\n"); |
0706f1c4 | 635 | #else |
bac429f0 SR |
636 | seq_printf(m, " Function Hit\n" |
637 | " -------- ---\n"); | |
0706f1c4 | 638 | #endif |
bac429f0 SR |
639 | return 0; |
640 | } | |
641 | ||
642 | static int function_stat_show(struct seq_file *m, void *v) | |
643 | { | |
493762fc | 644 | struct ftrace_profile *rec = v; |
bac429f0 | 645 | char str[KSYM_SYMBOL_LEN]; |
3aaba20f | 646 | int ret = 0; |
0706f1c4 | 647 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b SR |
648 | static struct trace_seq s; |
649 | unsigned long long avg; | |
e330b3bc | 650 | unsigned long long stddev; |
0706f1c4 | 651 | #endif |
3aaba20f LZ |
652 | mutex_lock(&ftrace_profile_lock); |
653 | ||
654 | /* we raced with function_profile_reset() */ | |
655 | if (unlikely(rec->counter == 0)) { | |
656 | ret = -EBUSY; | |
657 | goto out; | |
658 | } | |
bac429f0 SR |
659 | |
660 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
0706f1c4 SR |
661 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); |
662 | ||
663 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
664 | seq_printf(m, " "); | |
34886c8b SR |
665 | avg = rec->time; |
666 | do_div(avg, rec->counter); | |
667 | ||
e330b3bc CD |
668 | /* Sample standard deviation (s^2) */ |
669 | if (rec->counter <= 1) | |
670 | stddev = 0; | |
671 | else { | |
672 | stddev = rec->time_squared - rec->counter * avg * avg; | |
673 | /* | |
674 | * Divide only 1000 for ns^2 -> us^2 conversion. | |
675 | * trace_print_graph_duration will divide 1000 again. | |
676 | */ | |
677 | do_div(stddev, (rec->counter - 1) * 1000); | |
678 | } | |
679 | ||
34886c8b SR |
680 | trace_seq_init(&s); |
681 | trace_print_graph_duration(rec->time, &s); | |
682 | trace_seq_puts(&s, " "); | |
683 | trace_print_graph_duration(avg, &s); | |
e330b3bc CD |
684 | trace_seq_puts(&s, " "); |
685 | trace_print_graph_duration(stddev, &s); | |
0706f1c4 | 686 | trace_print_seq(m, &s); |
0706f1c4 SR |
687 | #endif |
688 | seq_putc(m, '\n'); | |
3aaba20f LZ |
689 | out: |
690 | mutex_unlock(&ftrace_profile_lock); | |
bac429f0 | 691 | |
3aaba20f | 692 | return ret; |
bac429f0 SR |
693 | } |
694 | ||
cafb168a | 695 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) |
bac429f0 | 696 | { |
493762fc | 697 | struct ftrace_profile_page *pg; |
bac429f0 | 698 | |
cafb168a | 699 | pg = stat->pages = stat->start; |
bac429f0 | 700 | |
493762fc SR |
701 | while (pg) { |
702 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | |
703 | pg->index = 0; | |
704 | pg = pg->next; | |
bac429f0 SR |
705 | } |
706 | ||
cafb168a | 707 | memset(stat->hash, 0, |
493762fc SR |
708 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); |
709 | } | |
bac429f0 | 710 | |
cafb168a | 711 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) |
493762fc SR |
712 | { |
713 | struct ftrace_profile_page *pg; | |
318e0a73 SR |
714 | int functions; |
715 | int pages; | |
493762fc | 716 | int i; |
bac429f0 | 717 | |
493762fc | 718 | /* If we already allocated, do nothing */ |
cafb168a | 719 | if (stat->pages) |
493762fc | 720 | return 0; |
bac429f0 | 721 | |
cafb168a SR |
722 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); |
723 | if (!stat->pages) | |
493762fc | 724 | return -ENOMEM; |
bac429f0 | 725 | |
318e0a73 SR |
726 | #ifdef CONFIG_DYNAMIC_FTRACE |
727 | functions = ftrace_update_tot_cnt; | |
728 | #else | |
729 | /* | |
730 | * We do not know the number of functions that exist because | |
731 | * dynamic tracing is what counts them. With past experience | |
732 | * we have around 20K functions. That should be more than enough. | |
733 | * It is highly unlikely we will execute every function in | |
734 | * the kernel. | |
735 | */ | |
736 | functions = 20000; | |
737 | #endif | |
738 | ||
cafb168a | 739 | pg = stat->start = stat->pages; |
bac429f0 | 740 | |
318e0a73 SR |
741 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); |
742 | ||
39e30cd1 | 743 | for (i = 1; i < pages; i++) { |
493762fc | 744 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
493762fc | 745 | if (!pg->next) |
318e0a73 | 746 | goto out_free; |
493762fc SR |
747 | pg = pg->next; |
748 | } | |
749 | ||
750 | return 0; | |
318e0a73 SR |
751 | |
752 | out_free: | |
753 | pg = stat->start; | |
754 | while (pg) { | |
755 | unsigned long tmp = (unsigned long)pg; | |
756 | ||
757 | pg = pg->next; | |
758 | free_page(tmp); | |
759 | } | |
760 | ||
318e0a73 SR |
761 | stat->pages = NULL; |
762 | stat->start = NULL; | |
763 | ||
764 | return -ENOMEM; | |
bac429f0 SR |
765 | } |
766 | ||
cafb168a | 767 | static int ftrace_profile_init_cpu(int cpu) |
bac429f0 | 768 | { |
cafb168a | 769 | struct ftrace_profile_stat *stat; |
493762fc | 770 | int size; |
bac429f0 | 771 | |
cafb168a SR |
772 | stat = &per_cpu(ftrace_profile_stats, cpu); |
773 | ||
774 | if (stat->hash) { | |
493762fc | 775 | /* If the profile is already created, simply reset it */ |
cafb168a | 776 | ftrace_profile_reset(stat); |
493762fc SR |
777 | return 0; |
778 | } | |
bac429f0 | 779 | |
493762fc SR |
780 | /* |
781 | * We are profiling all functions, but usually only a few thousand | |
782 | * functions are hit. We'll make a hash of 1024 items. | |
783 | */ | |
784 | size = FTRACE_PROFILE_HASH_SIZE; | |
bac429f0 | 785 | |
cafb168a | 786 | stat->hash = kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL); |
493762fc | 787 | |
cafb168a | 788 | if (!stat->hash) |
493762fc SR |
789 | return -ENOMEM; |
790 | ||
318e0a73 | 791 | /* Preallocate the function profiling pages */ |
cafb168a SR |
792 | if (ftrace_profile_pages_init(stat) < 0) { |
793 | kfree(stat->hash); | |
794 | stat->hash = NULL; | |
493762fc SR |
795 | return -ENOMEM; |
796 | } | |
797 | ||
798 | return 0; | |
bac429f0 SR |
799 | } |
800 | ||
cafb168a SR |
801 | static int ftrace_profile_init(void) |
802 | { | |
803 | int cpu; | |
804 | int ret = 0; | |
805 | ||
885154ce | 806 | for_each_possible_cpu(cpu) { |
cafb168a SR |
807 | ret = ftrace_profile_init_cpu(cpu); |
808 | if (ret) | |
809 | break; | |
810 | } | |
811 | ||
812 | return ret; | |
813 | } | |
814 | ||
493762fc | 815 | /* interrupts must be disabled */ |
cafb168a SR |
816 | static struct ftrace_profile * |
817 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) | |
bac429f0 | 818 | { |
493762fc | 819 | struct ftrace_profile *rec; |
bac429f0 | 820 | struct hlist_head *hhd; |
bac429f0 SR |
821 | unsigned long key; |
822 | ||
20079ebe | 823 | key = hash_long(ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 824 | hhd = &stat->hash[key]; |
bac429f0 SR |
825 | |
826 | if (hlist_empty(hhd)) | |
827 | return NULL; | |
828 | ||
1bb539ca | 829 | hlist_for_each_entry_rcu_notrace(rec, hhd, node) { |
bac429f0 | 830 | if (rec->ip == ip) |
493762fc SR |
831 | return rec; |
832 | } | |
833 | ||
834 | return NULL; | |
835 | } | |
836 | ||
cafb168a SR |
837 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, |
838 | struct ftrace_profile *rec) | |
493762fc SR |
839 | { |
840 | unsigned long key; | |
841 | ||
20079ebe | 842 | key = hash_long(rec->ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 843 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); |
493762fc SR |
844 | } |
845 | ||
318e0a73 SR |
846 | /* |
847 | * The memory is already allocated, this simply finds a new record to use. | |
848 | */ | |
493762fc | 849 | static struct ftrace_profile * |
318e0a73 | 850 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) |
493762fc SR |
851 | { |
852 | struct ftrace_profile *rec = NULL; | |
853 | ||
318e0a73 | 854 | /* prevent recursion (from NMIs) */ |
cafb168a | 855 | if (atomic_inc_return(&stat->disabled) != 1) |
493762fc SR |
856 | goto out; |
857 | ||
493762fc | 858 | /* |
318e0a73 SR |
859 | * Try to find the function again since an NMI |
860 | * could have added it | |
493762fc | 861 | */ |
cafb168a | 862 | rec = ftrace_find_profiled_func(stat, ip); |
493762fc | 863 | if (rec) |
cafb168a | 864 | goto out; |
493762fc | 865 | |
cafb168a SR |
866 | if (stat->pages->index == PROFILES_PER_PAGE) { |
867 | if (!stat->pages->next) | |
868 | goto out; | |
869 | stat->pages = stat->pages->next; | |
bac429f0 | 870 | } |
493762fc | 871 | |
cafb168a | 872 | rec = &stat->pages->records[stat->pages->index++]; |
493762fc | 873 | rec->ip = ip; |
cafb168a | 874 | ftrace_add_profile(stat, rec); |
493762fc | 875 | |
bac429f0 | 876 | out: |
cafb168a | 877 | atomic_dec(&stat->disabled); |
bac429f0 SR |
878 | |
879 | return rec; | |
880 | } | |
881 | ||
882 | static void | |
2f5f6ad9 | 883 | function_profile_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 884 | struct ftrace_ops *ops, struct pt_regs *regs) |
bac429f0 | 885 | { |
cafb168a | 886 | struct ftrace_profile_stat *stat; |
493762fc | 887 | struct ftrace_profile *rec; |
bac429f0 SR |
888 | unsigned long flags; |
889 | ||
890 | if (!ftrace_profile_enabled) | |
891 | return; | |
892 | ||
893 | local_irq_save(flags); | |
cafb168a SR |
894 | |
895 | stat = &__get_cpu_var(ftrace_profile_stats); | |
0f6ce3de | 896 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
897 | goto out; |
898 | ||
899 | rec = ftrace_find_profiled_func(stat, ip); | |
493762fc | 900 | if (!rec) { |
318e0a73 | 901 | rec = ftrace_profile_alloc(stat, ip); |
493762fc SR |
902 | if (!rec) |
903 | goto out; | |
904 | } | |
bac429f0 SR |
905 | |
906 | rec->counter++; | |
907 | out: | |
908 | local_irq_restore(flags); | |
909 | } | |
910 | ||
0706f1c4 SR |
911 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
912 | static int profile_graph_entry(struct ftrace_graph_ent *trace) | |
913 | { | |
a1e2e31d | 914 | function_profile_call(trace->func, 0, NULL, NULL); |
0706f1c4 SR |
915 | return 1; |
916 | } | |
917 | ||
918 | static void profile_graph_return(struct ftrace_graph_ret *trace) | |
919 | { | |
cafb168a | 920 | struct ftrace_profile_stat *stat; |
a2a16d6a | 921 | unsigned long long calltime; |
0706f1c4 | 922 | struct ftrace_profile *rec; |
cafb168a | 923 | unsigned long flags; |
0706f1c4 SR |
924 | |
925 | local_irq_save(flags); | |
cafb168a | 926 | stat = &__get_cpu_var(ftrace_profile_stats); |
0f6ce3de | 927 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
928 | goto out; |
929 | ||
37e44bc5 SR |
930 | /* If the calltime was zero'd ignore it */ |
931 | if (!trace->calltime) | |
932 | goto out; | |
933 | ||
a2a16d6a SR |
934 | calltime = trace->rettime - trace->calltime; |
935 | ||
936 | if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) { | |
937 | int index; | |
938 | ||
939 | index = trace->depth; | |
940 | ||
941 | /* Append this call time to the parent time to subtract */ | |
942 | if (index) | |
943 | current->ret_stack[index - 1].subtime += calltime; | |
944 | ||
945 | if (current->ret_stack[index].subtime < calltime) | |
946 | calltime -= current->ret_stack[index].subtime; | |
947 | else | |
948 | calltime = 0; | |
949 | } | |
950 | ||
cafb168a | 951 | rec = ftrace_find_profiled_func(stat, trace->func); |
e330b3bc | 952 | if (rec) { |
a2a16d6a | 953 | rec->time += calltime; |
e330b3bc CD |
954 | rec->time_squared += calltime * calltime; |
955 | } | |
a2a16d6a | 956 | |
cafb168a | 957 | out: |
0706f1c4 SR |
958 | local_irq_restore(flags); |
959 | } | |
960 | ||
961 | static int register_ftrace_profiler(void) | |
962 | { | |
963 | return register_ftrace_graph(&profile_graph_return, | |
964 | &profile_graph_entry); | |
965 | } | |
966 | ||
967 | static void unregister_ftrace_profiler(void) | |
968 | { | |
969 | unregister_ftrace_graph(); | |
970 | } | |
971 | #else | |
bd38c0e6 | 972 | static struct ftrace_ops ftrace_profile_ops __read_mostly = { |
fb9fb015 | 973 | .func = function_profile_call, |
f04f24fb MH |
974 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, |
975 | INIT_REGEX_LOCK(ftrace_profile_ops) | |
bac429f0 SR |
976 | }; |
977 | ||
0706f1c4 SR |
978 | static int register_ftrace_profiler(void) |
979 | { | |
980 | return register_ftrace_function(&ftrace_profile_ops); | |
981 | } | |
982 | ||
983 | static void unregister_ftrace_profiler(void) | |
984 | { | |
985 | unregister_ftrace_function(&ftrace_profile_ops); | |
986 | } | |
987 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
988 | ||
bac429f0 SR |
989 | static ssize_t |
990 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | |
991 | size_t cnt, loff_t *ppos) | |
992 | { | |
993 | unsigned long val; | |
bac429f0 SR |
994 | int ret; |
995 | ||
22fe9b54 PH |
996 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
997 | if (ret) | |
bac429f0 SR |
998 | return ret; |
999 | ||
1000 | val = !!val; | |
1001 | ||
1002 | mutex_lock(&ftrace_profile_lock); | |
1003 | if (ftrace_profile_enabled ^ val) { | |
1004 | if (val) { | |
493762fc SR |
1005 | ret = ftrace_profile_init(); |
1006 | if (ret < 0) { | |
1007 | cnt = ret; | |
1008 | goto out; | |
1009 | } | |
1010 | ||
0706f1c4 SR |
1011 | ret = register_ftrace_profiler(); |
1012 | if (ret < 0) { | |
1013 | cnt = ret; | |
1014 | goto out; | |
1015 | } | |
bac429f0 SR |
1016 | ftrace_profile_enabled = 1; |
1017 | } else { | |
1018 | ftrace_profile_enabled = 0; | |
0f6ce3de SR |
1019 | /* |
1020 | * unregister_ftrace_profiler calls stop_machine | |
1021 | * so this acts like an synchronize_sched. | |
1022 | */ | |
0706f1c4 | 1023 | unregister_ftrace_profiler(); |
bac429f0 SR |
1024 | } |
1025 | } | |
493762fc | 1026 | out: |
bac429f0 SR |
1027 | mutex_unlock(&ftrace_profile_lock); |
1028 | ||
cf8517cf | 1029 | *ppos += cnt; |
bac429f0 SR |
1030 | |
1031 | return cnt; | |
1032 | } | |
1033 | ||
493762fc SR |
1034 | static ssize_t |
1035 | ftrace_profile_read(struct file *filp, char __user *ubuf, | |
1036 | size_t cnt, loff_t *ppos) | |
1037 | { | |
fb9fb015 | 1038 | char buf[64]; /* big enough to hold a number */ |
493762fc SR |
1039 | int r; |
1040 | ||
1041 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | |
1042 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
1043 | } | |
1044 | ||
bac429f0 SR |
1045 | static const struct file_operations ftrace_profile_fops = { |
1046 | .open = tracing_open_generic, | |
1047 | .read = ftrace_profile_read, | |
1048 | .write = ftrace_profile_write, | |
6038f373 | 1049 | .llseek = default_llseek, |
bac429f0 SR |
1050 | }; |
1051 | ||
cafb168a SR |
1052 | /* used to initialize the real stat files */ |
1053 | static struct tracer_stat function_stats __initdata = { | |
fb9fb015 SR |
1054 | .name = "functions", |
1055 | .stat_start = function_stat_start, | |
1056 | .stat_next = function_stat_next, | |
1057 | .stat_cmp = function_stat_cmp, | |
1058 | .stat_headers = function_stat_headers, | |
1059 | .stat_show = function_stat_show | |
cafb168a SR |
1060 | }; |
1061 | ||
6ab5d668 | 1062 | static __init void ftrace_profile_debugfs(struct dentry *d_tracer) |
bac429f0 | 1063 | { |
cafb168a | 1064 | struct ftrace_profile_stat *stat; |
bac429f0 | 1065 | struct dentry *entry; |
cafb168a | 1066 | char *name; |
bac429f0 | 1067 | int ret; |
cafb168a SR |
1068 | int cpu; |
1069 | ||
1070 | for_each_possible_cpu(cpu) { | |
1071 | stat = &per_cpu(ftrace_profile_stats, cpu); | |
1072 | ||
1073 | /* allocate enough for function name + cpu number */ | |
1074 | name = kmalloc(32, GFP_KERNEL); | |
1075 | if (!name) { | |
1076 | /* | |
1077 | * The files created are permanent, if something happens | |
1078 | * we still do not free memory. | |
1079 | */ | |
cafb168a SR |
1080 | WARN(1, |
1081 | "Could not allocate stat file for cpu %d\n", | |
1082 | cpu); | |
1083 | return; | |
1084 | } | |
1085 | stat->stat = function_stats; | |
1086 | snprintf(name, 32, "function%d", cpu); | |
1087 | stat->stat.name = name; | |
1088 | ret = register_stat_tracer(&stat->stat); | |
1089 | if (ret) { | |
1090 | WARN(1, | |
1091 | "Could not register function stat for cpu %d\n", | |
1092 | cpu); | |
1093 | kfree(name); | |
1094 | return; | |
1095 | } | |
bac429f0 SR |
1096 | } |
1097 | ||
1098 | entry = debugfs_create_file("function_profile_enabled", 0644, | |
1099 | d_tracer, NULL, &ftrace_profile_fops); | |
1100 | if (!entry) | |
1101 | pr_warning("Could not create debugfs " | |
1102 | "'function_profile_enabled' entry\n"); | |
1103 | } | |
1104 | ||
bac429f0 | 1105 | #else /* CONFIG_FUNCTION_PROFILER */ |
6ab5d668 | 1106 | static __init void ftrace_profile_debugfs(struct dentry *d_tracer) |
bac429f0 SR |
1107 | { |
1108 | } | |
bac429f0 SR |
1109 | #endif /* CONFIG_FUNCTION_PROFILER */ |
1110 | ||
493762fc SR |
1111 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; |
1112 | ||
7f49ef69 SRRH |
1113 | loff_t |
1114 | ftrace_filter_lseek(struct file *file, loff_t offset, int whence) | |
1115 | { | |
1116 | loff_t ret; | |
1117 | ||
1118 | if (file->f_mode & FMODE_READ) | |
1119 | ret = seq_lseek(file, offset, whence); | |
1120 | else | |
1121 | file->f_pos = ret = 1; | |
1122 | ||
1123 | return ret; | |
1124 | } | |
1125 | ||
493762fc SR |
1126 | #ifdef CONFIG_DYNAMIC_FTRACE |
1127 | ||
1128 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD | |
1129 | # error Dynamic ftrace depends on MCOUNT_RECORD | |
1130 | #endif | |
1131 | ||
1132 | static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly; | |
1133 | ||
1134 | struct ftrace_func_probe { | |
1135 | struct hlist_node node; | |
1136 | struct ftrace_probe_ops *ops; | |
1137 | unsigned long flags; | |
1138 | unsigned long ip; | |
1139 | void *data; | |
7818b388 | 1140 | struct list_head free_list; |
493762fc SR |
1141 | }; |
1142 | ||
b448c4e3 SR |
1143 | struct ftrace_func_entry { |
1144 | struct hlist_node hlist; | |
1145 | unsigned long ip; | |
1146 | }; | |
1147 | ||
1148 | struct ftrace_hash { | |
1149 | unsigned long size_bits; | |
1150 | struct hlist_head *buckets; | |
1151 | unsigned long count; | |
07fd5515 | 1152 | struct rcu_head rcu; |
b448c4e3 SR |
1153 | }; |
1154 | ||
33dc9b12 SR |
1155 | /* |
1156 | * We make these constant because no one should touch them, | |
1157 | * but they are used as the default "empty hash", to avoid allocating | |
1158 | * it all the time. These are in a read only section such that if | |
1159 | * anyone does try to modify it, it will cause an exception. | |
1160 | */ | |
1161 | static const struct hlist_head empty_buckets[1]; | |
1162 | static const struct ftrace_hash empty_hash = { | |
1163 | .buckets = (struct hlist_head *)empty_buckets, | |
1cf41dd7 | 1164 | }; |
33dc9b12 | 1165 | #define EMPTY_HASH ((struct ftrace_hash *)&empty_hash) |
493762fc | 1166 | |
2b499381 | 1167 | static struct ftrace_ops global_ops = { |
f45948e8 | 1168 | .func = ftrace_stub, |
33dc9b12 SR |
1169 | .notrace_hash = EMPTY_HASH, |
1170 | .filter_hash = EMPTY_HASH, | |
f04f24fb MH |
1171 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, |
1172 | INIT_REGEX_LOCK(global_ops) | |
f45948e8 SR |
1173 | }; |
1174 | ||
493762fc SR |
1175 | struct ftrace_page { |
1176 | struct ftrace_page *next; | |
a7900875 | 1177 | struct dyn_ftrace *records; |
493762fc | 1178 | int index; |
a7900875 | 1179 | int size; |
493762fc SR |
1180 | }; |
1181 | ||
85ae32ae SR |
1182 | static struct ftrace_page *ftrace_new_pgs; |
1183 | ||
a7900875 SR |
1184 | #define ENTRY_SIZE sizeof(struct dyn_ftrace) |
1185 | #define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE) | |
493762fc SR |
1186 | |
1187 | /* estimate from running different kernels */ | |
1188 | #define NR_TO_INIT 10000 | |
1189 | ||
1190 | static struct ftrace_page *ftrace_pages_start; | |
1191 | static struct ftrace_page *ftrace_pages; | |
1192 | ||
06a51d93 SR |
1193 | static bool ftrace_hash_empty(struct ftrace_hash *hash) |
1194 | { | |
1195 | return !hash || !hash->count; | |
1196 | } | |
1197 | ||
b448c4e3 SR |
1198 | static struct ftrace_func_entry * |
1199 | ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
1200 | { | |
1201 | unsigned long key; | |
1202 | struct ftrace_func_entry *entry; | |
1203 | struct hlist_head *hhd; | |
b448c4e3 | 1204 | |
06a51d93 | 1205 | if (ftrace_hash_empty(hash)) |
b448c4e3 SR |
1206 | return NULL; |
1207 | ||
1208 | if (hash->size_bits > 0) | |
1209 | key = hash_long(ip, hash->size_bits); | |
1210 | else | |
1211 | key = 0; | |
1212 | ||
1213 | hhd = &hash->buckets[key]; | |
1214 | ||
1bb539ca | 1215 | hlist_for_each_entry_rcu_notrace(entry, hhd, hlist) { |
b448c4e3 SR |
1216 | if (entry->ip == ip) |
1217 | return entry; | |
1218 | } | |
1219 | return NULL; | |
1220 | } | |
1221 | ||
33dc9b12 SR |
1222 | static void __add_hash_entry(struct ftrace_hash *hash, |
1223 | struct ftrace_func_entry *entry) | |
b448c4e3 | 1224 | { |
b448c4e3 SR |
1225 | struct hlist_head *hhd; |
1226 | unsigned long key; | |
1227 | ||
b448c4e3 | 1228 | if (hash->size_bits) |
33dc9b12 | 1229 | key = hash_long(entry->ip, hash->size_bits); |
b448c4e3 SR |
1230 | else |
1231 | key = 0; | |
1232 | ||
b448c4e3 SR |
1233 | hhd = &hash->buckets[key]; |
1234 | hlist_add_head(&entry->hlist, hhd); | |
1235 | hash->count++; | |
33dc9b12 SR |
1236 | } |
1237 | ||
1238 | static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) | |
1239 | { | |
1240 | struct ftrace_func_entry *entry; | |
1241 | ||
1242 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
1243 | if (!entry) | |
1244 | return -ENOMEM; | |
1245 | ||
1246 | entry->ip = ip; | |
1247 | __add_hash_entry(hash, entry); | |
b448c4e3 SR |
1248 | |
1249 | return 0; | |
1250 | } | |
1251 | ||
1252 | static void | |
33dc9b12 | 1253 | free_hash_entry(struct ftrace_hash *hash, |
b448c4e3 SR |
1254 | struct ftrace_func_entry *entry) |
1255 | { | |
1256 | hlist_del(&entry->hlist); | |
1257 | kfree(entry); | |
1258 | hash->count--; | |
1259 | } | |
1260 | ||
33dc9b12 SR |
1261 | static void |
1262 | remove_hash_entry(struct ftrace_hash *hash, | |
1263 | struct ftrace_func_entry *entry) | |
1264 | { | |
1265 | hlist_del(&entry->hlist); | |
1266 | hash->count--; | |
1267 | } | |
1268 | ||
b448c4e3 SR |
1269 | static void ftrace_hash_clear(struct ftrace_hash *hash) |
1270 | { | |
1271 | struct hlist_head *hhd; | |
b67bfe0d | 1272 | struct hlist_node *tn; |
b448c4e3 SR |
1273 | struct ftrace_func_entry *entry; |
1274 | int size = 1 << hash->size_bits; | |
1275 | int i; | |
1276 | ||
33dc9b12 SR |
1277 | if (!hash->count) |
1278 | return; | |
1279 | ||
b448c4e3 SR |
1280 | for (i = 0; i < size; i++) { |
1281 | hhd = &hash->buckets[i]; | |
b67bfe0d | 1282 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) |
33dc9b12 | 1283 | free_hash_entry(hash, entry); |
b448c4e3 SR |
1284 | } |
1285 | FTRACE_WARN_ON(hash->count); | |
1286 | } | |
1287 | ||
33dc9b12 SR |
1288 | static void free_ftrace_hash(struct ftrace_hash *hash) |
1289 | { | |
1290 | if (!hash || hash == EMPTY_HASH) | |
1291 | return; | |
1292 | ftrace_hash_clear(hash); | |
1293 | kfree(hash->buckets); | |
1294 | kfree(hash); | |
1295 | } | |
1296 | ||
07fd5515 SR |
1297 | static void __free_ftrace_hash_rcu(struct rcu_head *rcu) |
1298 | { | |
1299 | struct ftrace_hash *hash; | |
1300 | ||
1301 | hash = container_of(rcu, struct ftrace_hash, rcu); | |
1302 | free_ftrace_hash(hash); | |
1303 | } | |
1304 | ||
1305 | static void free_ftrace_hash_rcu(struct ftrace_hash *hash) | |
1306 | { | |
1307 | if (!hash || hash == EMPTY_HASH) | |
1308 | return; | |
1309 | call_rcu_sched(&hash->rcu, __free_ftrace_hash_rcu); | |
1310 | } | |
1311 | ||
5500fa51 JO |
1312 | void ftrace_free_filter(struct ftrace_ops *ops) |
1313 | { | |
f04f24fb | 1314 | ftrace_ops_init(ops); |
5500fa51 JO |
1315 | free_ftrace_hash(ops->filter_hash); |
1316 | free_ftrace_hash(ops->notrace_hash); | |
1317 | } | |
1318 | ||
33dc9b12 SR |
1319 | static struct ftrace_hash *alloc_ftrace_hash(int size_bits) |
1320 | { | |
1321 | struct ftrace_hash *hash; | |
1322 | int size; | |
1323 | ||
1324 | hash = kzalloc(sizeof(*hash), GFP_KERNEL); | |
1325 | if (!hash) | |
1326 | return NULL; | |
1327 | ||
1328 | size = 1 << size_bits; | |
47b0edcb | 1329 | hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL); |
33dc9b12 SR |
1330 | |
1331 | if (!hash->buckets) { | |
1332 | kfree(hash); | |
1333 | return NULL; | |
1334 | } | |
1335 | ||
1336 | hash->size_bits = size_bits; | |
1337 | ||
1338 | return hash; | |
1339 | } | |
1340 | ||
1341 | static struct ftrace_hash * | |
1342 | alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) | |
1343 | { | |
1344 | struct ftrace_func_entry *entry; | |
1345 | struct ftrace_hash *new_hash; | |
33dc9b12 SR |
1346 | int size; |
1347 | int ret; | |
1348 | int i; | |
1349 | ||
1350 | new_hash = alloc_ftrace_hash(size_bits); | |
1351 | if (!new_hash) | |
1352 | return NULL; | |
1353 | ||
1354 | /* Empty hash? */ | |
06a51d93 | 1355 | if (ftrace_hash_empty(hash)) |
33dc9b12 SR |
1356 | return new_hash; |
1357 | ||
1358 | size = 1 << hash->size_bits; | |
1359 | for (i = 0; i < size; i++) { | |
b67bfe0d | 1360 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { |
33dc9b12 SR |
1361 | ret = add_hash_entry(new_hash, entry->ip); |
1362 | if (ret < 0) | |
1363 | goto free_hash; | |
1364 | } | |
1365 | } | |
1366 | ||
1367 | FTRACE_WARN_ON(new_hash->count != hash->count); | |
1368 | ||
1369 | return new_hash; | |
1370 | ||
1371 | free_hash: | |
1372 | free_ftrace_hash(new_hash); | |
1373 | return NULL; | |
1374 | } | |
1375 | ||
41fb61c2 SR |
1376 | static void |
1377 | ftrace_hash_rec_disable(struct ftrace_ops *ops, int filter_hash); | |
1378 | static void | |
1379 | ftrace_hash_rec_enable(struct ftrace_ops *ops, int filter_hash); | |
1380 | ||
33dc9b12 | 1381 | static int |
41fb61c2 SR |
1382 | ftrace_hash_move(struct ftrace_ops *ops, int enable, |
1383 | struct ftrace_hash **dst, struct ftrace_hash *src) | |
33dc9b12 SR |
1384 | { |
1385 | struct ftrace_func_entry *entry; | |
b67bfe0d | 1386 | struct hlist_node *tn; |
33dc9b12 | 1387 | struct hlist_head *hhd; |
07fd5515 SR |
1388 | struct ftrace_hash *old_hash; |
1389 | struct ftrace_hash *new_hash; | |
33dc9b12 SR |
1390 | int size = src->count; |
1391 | int bits = 0; | |
41fb61c2 | 1392 | int ret; |
33dc9b12 SR |
1393 | int i; |
1394 | ||
41fb61c2 SR |
1395 | /* |
1396 | * Remove the current set, update the hash and add | |
1397 | * them back. | |
1398 | */ | |
1399 | ftrace_hash_rec_disable(ops, enable); | |
1400 | ||
33dc9b12 SR |
1401 | /* |
1402 | * If the new source is empty, just free dst and assign it | |
1403 | * the empty_hash. | |
1404 | */ | |
1405 | if (!src->count) { | |
07fd5515 SR |
1406 | free_ftrace_hash_rcu(*dst); |
1407 | rcu_assign_pointer(*dst, EMPTY_HASH); | |
d4d34b98 SR |
1408 | /* still need to update the function records */ |
1409 | ret = 0; | |
1410 | goto out; | |
33dc9b12 SR |
1411 | } |
1412 | ||
33dc9b12 SR |
1413 | /* |
1414 | * Make the hash size about 1/2 the # found | |
1415 | */ | |
1416 | for (size /= 2; size; size >>= 1) | |
1417 | bits++; | |
1418 | ||
1419 | /* Don't allocate too much */ | |
1420 | if (bits > FTRACE_HASH_MAX_BITS) | |
1421 | bits = FTRACE_HASH_MAX_BITS; | |
1422 | ||
41fb61c2 | 1423 | ret = -ENOMEM; |
07fd5515 SR |
1424 | new_hash = alloc_ftrace_hash(bits); |
1425 | if (!new_hash) | |
41fb61c2 | 1426 | goto out; |
33dc9b12 SR |
1427 | |
1428 | size = 1 << src->size_bits; | |
1429 | for (i = 0; i < size; i++) { | |
1430 | hhd = &src->buckets[i]; | |
b67bfe0d | 1431 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) { |
33dc9b12 | 1432 | remove_hash_entry(src, entry); |
07fd5515 | 1433 | __add_hash_entry(new_hash, entry); |
33dc9b12 SR |
1434 | } |
1435 | } | |
1436 | ||
07fd5515 SR |
1437 | old_hash = *dst; |
1438 | rcu_assign_pointer(*dst, new_hash); | |
1439 | free_ftrace_hash_rcu(old_hash); | |
1440 | ||
41fb61c2 SR |
1441 | ret = 0; |
1442 | out: | |
1443 | /* | |
1444 | * Enable regardless of ret: | |
1445 | * On success, we enable the new hash. | |
1446 | * On failure, we re-enable the original hash. | |
1447 | */ | |
1448 | ftrace_hash_rec_enable(ops, enable); | |
1449 | ||
1450 | return ret; | |
33dc9b12 SR |
1451 | } |
1452 | ||
b848914c SR |
1453 | /* |
1454 | * Test the hashes for this ops to see if we want to call | |
1455 | * the ops->func or not. | |
1456 | * | |
1457 | * It's a match if the ip is in the ops->filter_hash or | |
1458 | * the filter_hash does not exist or is empty, | |
1459 | * AND | |
1460 | * the ip is not in the ops->notrace_hash. | |
cdbe61bf SR |
1461 | * |
1462 | * This needs to be called with preemption disabled as | |
1463 | * the hashes are freed with call_rcu_sched(). | |
b848914c SR |
1464 | */ |
1465 | static int | |
29632b10 | 1466 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs) |
b848914c SR |
1467 | { |
1468 | struct ftrace_hash *filter_hash; | |
1469 | struct ftrace_hash *notrace_hash; | |
1470 | int ret; | |
1471 | ||
29632b10 SRRH |
1472 | #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
1473 | /* | |
1474 | * There's a small race when adding ops that the ftrace handler | |
1475 | * that wants regs, may be called without them. We can not | |
1476 | * allow that handler to be called if regs is NULL. | |
1477 | */ | |
1478 | if (regs == NULL && (ops->flags & FTRACE_OPS_FL_SAVE_REGS)) | |
1479 | return 0; | |
1480 | #endif | |
1481 | ||
1bb539ca SR |
1482 | filter_hash = rcu_dereference_raw_notrace(ops->filter_hash); |
1483 | notrace_hash = rcu_dereference_raw_notrace(ops->notrace_hash); | |
b848914c | 1484 | |
06a51d93 | 1485 | if ((ftrace_hash_empty(filter_hash) || |
b848914c | 1486 | ftrace_lookup_ip(filter_hash, ip)) && |
06a51d93 | 1487 | (ftrace_hash_empty(notrace_hash) || |
b848914c SR |
1488 | !ftrace_lookup_ip(notrace_hash, ip))) |
1489 | ret = 1; | |
1490 | else | |
1491 | ret = 0; | |
b848914c SR |
1492 | |
1493 | return ret; | |
1494 | } | |
1495 | ||
493762fc SR |
1496 | /* |
1497 | * This is a double for. Do not use 'break' to break out of the loop, | |
1498 | * you must use a goto. | |
1499 | */ | |
1500 | #define do_for_each_ftrace_rec(pg, rec) \ | |
1501 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
1502 | int _____i; \ | |
1503 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
1504 | rec = &pg->records[_____i]; | |
1505 | ||
1506 | #define while_for_each_ftrace_rec() \ | |
1507 | } \ | |
1508 | } | |
1509 | ||
5855fead SR |
1510 | |
1511 | static int ftrace_cmp_recs(const void *a, const void *b) | |
1512 | { | |
a650e02a SR |
1513 | const struct dyn_ftrace *key = a; |
1514 | const struct dyn_ftrace *rec = b; | |
5855fead | 1515 | |
a650e02a | 1516 | if (key->flags < rec->ip) |
5855fead | 1517 | return -1; |
a650e02a SR |
1518 | if (key->ip >= rec->ip + MCOUNT_INSN_SIZE) |
1519 | return 1; | |
5855fead SR |
1520 | return 0; |
1521 | } | |
1522 | ||
f0cf973a | 1523 | static unsigned long ftrace_location_range(unsigned long start, unsigned long end) |
c88fd863 SR |
1524 | { |
1525 | struct ftrace_page *pg; | |
1526 | struct dyn_ftrace *rec; | |
5855fead | 1527 | struct dyn_ftrace key; |
c88fd863 | 1528 | |
a650e02a SR |
1529 | key.ip = start; |
1530 | key.flags = end; /* overload flags, as it is unsigned long */ | |
5855fead SR |
1531 | |
1532 | for (pg = ftrace_pages_start; pg; pg = pg->next) { | |
a650e02a SR |
1533 | if (end < pg->records[0].ip || |
1534 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) | |
9644302e | 1535 | continue; |
5855fead SR |
1536 | rec = bsearch(&key, pg->records, pg->index, |
1537 | sizeof(struct dyn_ftrace), | |
1538 | ftrace_cmp_recs); | |
1539 | if (rec) | |
f0cf973a | 1540 | return rec->ip; |
5855fead | 1541 | } |
c88fd863 SR |
1542 | |
1543 | return 0; | |
1544 | } | |
1545 | ||
a650e02a SR |
1546 | /** |
1547 | * ftrace_location - return true if the ip giving is a traced location | |
1548 | * @ip: the instruction pointer to check | |
1549 | * | |
f0cf973a | 1550 | * Returns rec->ip if @ip given is a pointer to a ftrace location. |
a650e02a SR |
1551 | * That is, the instruction that is either a NOP or call to |
1552 | * the function tracer. It checks the ftrace internal tables to | |
1553 | * determine if the address belongs or not. | |
1554 | */ | |
f0cf973a | 1555 | unsigned long ftrace_location(unsigned long ip) |
a650e02a SR |
1556 | { |
1557 | return ftrace_location_range(ip, ip); | |
1558 | } | |
1559 | ||
1560 | /** | |
1561 | * ftrace_text_reserved - return true if range contains an ftrace location | |
1562 | * @start: start of range to search | |
1563 | * @end: end of range to search (inclusive). @end points to the last byte to check. | |
1564 | * | |
1565 | * Returns 1 if @start and @end contains a ftrace location. | |
1566 | * That is, the instruction that is either a NOP or call to | |
1567 | * the function tracer. It checks the ftrace internal tables to | |
1568 | * determine if the address belongs or not. | |
1569 | */ | |
1570 | int ftrace_text_reserved(void *start, void *end) | |
1571 | { | |
f0cf973a SR |
1572 | unsigned long ret; |
1573 | ||
1574 | ret = ftrace_location_range((unsigned long)start, | |
1575 | (unsigned long)end); | |
1576 | ||
1577 | return (int)!!ret; | |
a650e02a SR |
1578 | } |
1579 | ||
ed926f9b SR |
1580 | static void __ftrace_hash_rec_update(struct ftrace_ops *ops, |
1581 | int filter_hash, | |
1582 | bool inc) | |
1583 | { | |
1584 | struct ftrace_hash *hash; | |
1585 | struct ftrace_hash *other_hash; | |
1586 | struct ftrace_page *pg; | |
1587 | struct dyn_ftrace *rec; | |
1588 | int count = 0; | |
1589 | int all = 0; | |
1590 | ||
1591 | /* Only update if the ops has been registered */ | |
1592 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
1593 | return; | |
1594 | ||
1595 | /* | |
1596 | * In the filter_hash case: | |
1597 | * If the count is zero, we update all records. | |
1598 | * Otherwise we just update the items in the hash. | |
1599 | * | |
1600 | * In the notrace_hash case: | |
1601 | * We enable the update in the hash. | |
1602 | * As disabling notrace means enabling the tracing, | |
1603 | * and enabling notrace means disabling, the inc variable | |
1604 | * gets inversed. | |
1605 | */ | |
1606 | if (filter_hash) { | |
1607 | hash = ops->filter_hash; | |
1608 | other_hash = ops->notrace_hash; | |
06a51d93 | 1609 | if (ftrace_hash_empty(hash)) |
ed926f9b SR |
1610 | all = 1; |
1611 | } else { | |
1612 | inc = !inc; | |
1613 | hash = ops->notrace_hash; | |
1614 | other_hash = ops->filter_hash; | |
1615 | /* | |
1616 | * If the notrace hash has no items, | |
1617 | * then there's nothing to do. | |
1618 | */ | |
06a51d93 | 1619 | if (ftrace_hash_empty(hash)) |
ed926f9b SR |
1620 | return; |
1621 | } | |
1622 | ||
1623 | do_for_each_ftrace_rec(pg, rec) { | |
1624 | int in_other_hash = 0; | |
1625 | int in_hash = 0; | |
1626 | int match = 0; | |
1627 | ||
1628 | if (all) { | |
1629 | /* | |
1630 | * Only the filter_hash affects all records. | |
1631 | * Update if the record is not in the notrace hash. | |
1632 | */ | |
b848914c | 1633 | if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip)) |
ed926f9b SR |
1634 | match = 1; |
1635 | } else { | |
06a51d93 SR |
1636 | in_hash = !!ftrace_lookup_ip(hash, rec->ip); |
1637 | in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip); | |
ed926f9b SR |
1638 | |
1639 | /* | |
1640 | * | |
1641 | */ | |
1642 | if (filter_hash && in_hash && !in_other_hash) | |
1643 | match = 1; | |
1644 | else if (!filter_hash && in_hash && | |
06a51d93 | 1645 | (in_other_hash || ftrace_hash_empty(other_hash))) |
ed926f9b SR |
1646 | match = 1; |
1647 | } | |
1648 | if (!match) | |
1649 | continue; | |
1650 | ||
1651 | if (inc) { | |
1652 | rec->flags++; | |
1653 | if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == FTRACE_REF_MAX)) | |
1654 | return; | |
08f6fba5 SR |
1655 | /* |
1656 | * If any ops wants regs saved for this function | |
1657 | * then all ops will get saved regs. | |
1658 | */ | |
1659 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) | |
1660 | rec->flags |= FTRACE_FL_REGS; | |
ed926f9b SR |
1661 | } else { |
1662 | if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == 0)) | |
1663 | return; | |
1664 | rec->flags--; | |
1665 | } | |
1666 | count++; | |
1667 | /* Shortcut, if we handled all records, we are done. */ | |
1668 | if (!all && count == hash->count) | |
1669 | return; | |
1670 | } while_for_each_ftrace_rec(); | |
1671 | } | |
1672 | ||
1673 | static void ftrace_hash_rec_disable(struct ftrace_ops *ops, | |
1674 | int filter_hash) | |
1675 | { | |
1676 | __ftrace_hash_rec_update(ops, filter_hash, 0); | |
1677 | } | |
1678 | ||
1679 | static void ftrace_hash_rec_enable(struct ftrace_ops *ops, | |
1680 | int filter_hash) | |
1681 | { | |
1682 | __ftrace_hash_rec_update(ops, filter_hash, 1); | |
1683 | } | |
1684 | ||
b17e8a37 SR |
1685 | static void print_ip_ins(const char *fmt, unsigned char *p) |
1686 | { | |
1687 | int i; | |
1688 | ||
1689 | printk(KERN_CONT "%s", fmt); | |
1690 | ||
1691 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
1692 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
1693 | } | |
1694 | ||
c88fd863 SR |
1695 | /** |
1696 | * ftrace_bug - report and shutdown function tracer | |
1697 | * @failed: The failed type (EFAULT, EINVAL, EPERM) | |
1698 | * @ip: The address that failed | |
1699 | * | |
1700 | * The arch code that enables or disables the function tracing | |
1701 | * can call ftrace_bug() when it has detected a problem in | |
1702 | * modifying the code. @failed should be one of either: | |
1703 | * EFAULT - if the problem happens on reading the @ip address | |
1704 | * EINVAL - if what is read at @ip is not what was expected | |
1705 | * EPERM - if the problem happens on writting to the @ip address | |
1706 | */ | |
1707 | void ftrace_bug(int failed, unsigned long ip) | |
b17e8a37 SR |
1708 | { |
1709 | switch (failed) { | |
1710 | case -EFAULT: | |
1711 | FTRACE_WARN_ON_ONCE(1); | |
1712 | pr_info("ftrace faulted on modifying "); | |
1713 | print_ip_sym(ip); | |
1714 | break; | |
1715 | case -EINVAL: | |
1716 | FTRACE_WARN_ON_ONCE(1); | |
1717 | pr_info("ftrace failed to modify "); | |
1718 | print_ip_sym(ip); | |
b17e8a37 | 1719 | print_ip_ins(" actual: ", (unsigned char *)ip); |
b17e8a37 SR |
1720 | printk(KERN_CONT "\n"); |
1721 | break; | |
1722 | case -EPERM: | |
1723 | FTRACE_WARN_ON_ONCE(1); | |
1724 | pr_info("ftrace faulted on writing "); | |
1725 | print_ip_sym(ip); | |
1726 | break; | |
1727 | default: | |
1728 | FTRACE_WARN_ON_ONCE(1); | |
1729 | pr_info("ftrace faulted on unknown error "); | |
1730 | print_ip_sym(ip); | |
1731 | } | |
1732 | } | |
1733 | ||
c88fd863 | 1734 | static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update) |
5072c59f | 1735 | { |
64fbcd16 | 1736 | unsigned long flag = 0UL; |
e7d3737e | 1737 | |
982c350b | 1738 | /* |
30fb6aa7 | 1739 | * If we are updating calls: |
982c350b | 1740 | * |
ed926f9b SR |
1741 | * If the record has a ref count, then we need to enable it |
1742 | * because someone is using it. | |
982c350b | 1743 | * |
ed926f9b SR |
1744 | * Otherwise we make sure its disabled. |
1745 | * | |
30fb6aa7 | 1746 | * If we are disabling calls, then disable all records that |
ed926f9b | 1747 | * are enabled. |
982c350b | 1748 | */ |
c88fd863 | 1749 | if (enable && (rec->flags & ~FTRACE_FL_MASK)) |
ed926f9b | 1750 | flag = FTRACE_FL_ENABLED; |
982c350b | 1751 | |
08f6fba5 SR |
1752 | /* |
1753 | * If enabling and the REGS flag does not match the REGS_EN, then | |
1754 | * do not ignore this record. Set flags to fail the compare against | |
1755 | * ENABLED. | |
1756 | */ | |
1757 | if (flag && | |
1758 | (!(rec->flags & FTRACE_FL_REGS) != !(rec->flags & FTRACE_FL_REGS_EN))) | |
1759 | flag |= FTRACE_FL_REGS; | |
1760 | ||
64fbcd16 XG |
1761 | /* If the state of this record hasn't changed, then do nothing */ |
1762 | if ((rec->flags & FTRACE_FL_ENABLED) == flag) | |
c88fd863 | 1763 | return FTRACE_UPDATE_IGNORE; |
982c350b | 1764 | |
64fbcd16 | 1765 | if (flag) { |
08f6fba5 SR |
1766 | /* Save off if rec is being enabled (for return value) */ |
1767 | flag ^= rec->flags & FTRACE_FL_ENABLED; | |
1768 | ||
1769 | if (update) { | |
c88fd863 | 1770 | rec->flags |= FTRACE_FL_ENABLED; |
08f6fba5 SR |
1771 | if (flag & FTRACE_FL_REGS) { |
1772 | if (rec->flags & FTRACE_FL_REGS) | |
1773 | rec->flags |= FTRACE_FL_REGS_EN; | |
1774 | else | |
1775 | rec->flags &= ~FTRACE_FL_REGS_EN; | |
1776 | } | |
1777 | } | |
1778 | ||
1779 | /* | |
1780 | * If this record is being updated from a nop, then | |
1781 | * return UPDATE_MAKE_CALL. | |
1782 | * Otherwise, if the EN flag is set, then return | |
1783 | * UPDATE_MODIFY_CALL_REGS to tell the caller to convert | |
1784 | * from the non-save regs, to a save regs function. | |
1785 | * Otherwise, | |
1786 | * return UPDATE_MODIFY_CALL to tell the caller to convert | |
1787 | * from the save regs, to a non-save regs function. | |
1788 | */ | |
1789 | if (flag & FTRACE_FL_ENABLED) | |
1790 | return FTRACE_UPDATE_MAKE_CALL; | |
1791 | else if (rec->flags & FTRACE_FL_REGS_EN) | |
1792 | return FTRACE_UPDATE_MODIFY_CALL_REGS; | |
1793 | else | |
1794 | return FTRACE_UPDATE_MODIFY_CALL; | |
c88fd863 SR |
1795 | } |
1796 | ||
08f6fba5 SR |
1797 | if (update) { |
1798 | /* If there's no more users, clear all flags */ | |
1799 | if (!(rec->flags & ~FTRACE_FL_MASK)) | |
1800 | rec->flags = 0; | |
1801 | else | |
1802 | /* Just disable the record (keep REGS state) */ | |
1803 | rec->flags &= ~FTRACE_FL_ENABLED; | |
1804 | } | |
c88fd863 SR |
1805 | |
1806 | return FTRACE_UPDATE_MAKE_NOP; | |
1807 | } | |
1808 | ||
1809 | /** | |
1810 | * ftrace_update_record, set a record that now is tracing or not | |
1811 | * @rec: the record to update | |
1812 | * @enable: set to 1 if the record is tracing, zero to force disable | |
1813 | * | |
1814 | * The records that represent all functions that can be traced need | |
1815 | * to be updated when tracing has been enabled. | |
1816 | */ | |
1817 | int ftrace_update_record(struct dyn_ftrace *rec, int enable) | |
1818 | { | |
1819 | return ftrace_check_record(rec, enable, 1); | |
1820 | } | |
1821 | ||
1822 | /** | |
1823 | * ftrace_test_record, check if the record has been enabled or not | |
1824 | * @rec: the record to test | |
1825 | * @enable: set to 1 to check if enabled, 0 if it is disabled | |
1826 | * | |
1827 | * The arch code may need to test if a record is already set to | |
1828 | * tracing to determine how to modify the function code that it | |
1829 | * represents. | |
1830 | */ | |
1831 | int ftrace_test_record(struct dyn_ftrace *rec, int enable) | |
1832 | { | |
1833 | return ftrace_check_record(rec, enable, 0); | |
1834 | } | |
1835 | ||
1836 | static int | |
1837 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) | |
1838 | { | |
08f6fba5 | 1839 | unsigned long ftrace_old_addr; |
c88fd863 SR |
1840 | unsigned long ftrace_addr; |
1841 | int ret; | |
1842 | ||
c88fd863 SR |
1843 | ret = ftrace_update_record(rec, enable); |
1844 | ||
08f6fba5 SR |
1845 | if (rec->flags & FTRACE_FL_REGS) |
1846 | ftrace_addr = (unsigned long)FTRACE_REGS_ADDR; | |
1847 | else | |
1848 | ftrace_addr = (unsigned long)FTRACE_ADDR; | |
1849 | ||
c88fd863 SR |
1850 | switch (ret) { |
1851 | case FTRACE_UPDATE_IGNORE: | |
1852 | return 0; | |
1853 | ||
1854 | case FTRACE_UPDATE_MAKE_CALL: | |
64fbcd16 | 1855 | return ftrace_make_call(rec, ftrace_addr); |
c88fd863 SR |
1856 | |
1857 | case FTRACE_UPDATE_MAKE_NOP: | |
1858 | return ftrace_make_nop(NULL, rec, ftrace_addr); | |
08f6fba5 SR |
1859 | |
1860 | case FTRACE_UPDATE_MODIFY_CALL_REGS: | |
1861 | case FTRACE_UPDATE_MODIFY_CALL: | |
1862 | if (rec->flags & FTRACE_FL_REGS) | |
1863 | ftrace_old_addr = (unsigned long)FTRACE_ADDR; | |
1864 | else | |
1865 | ftrace_old_addr = (unsigned long)FTRACE_REGS_ADDR; | |
1866 | ||
1867 | return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr); | |
5072c59f SR |
1868 | } |
1869 | ||
c88fd863 | 1870 | return -1; /* unknow ftrace bug */ |
5072c59f SR |
1871 | } |
1872 | ||
e4f5d544 | 1873 | void __weak ftrace_replace_code(int enable) |
3c1720f0 | 1874 | { |
3c1720f0 SR |
1875 | struct dyn_ftrace *rec; |
1876 | struct ftrace_page *pg; | |
6a24a244 | 1877 | int failed; |
3c1720f0 | 1878 | |
45a4a237 SR |
1879 | if (unlikely(ftrace_disabled)) |
1880 | return; | |
1881 | ||
265c831c | 1882 | do_for_each_ftrace_rec(pg, rec) { |
e4f5d544 | 1883 | failed = __ftrace_replace_code(rec, enable); |
fa9d13cf | 1884 | if (failed) { |
3279ba37 SR |
1885 | ftrace_bug(failed, rec->ip); |
1886 | /* Stop processing */ | |
1887 | return; | |
3c1720f0 | 1888 | } |
265c831c | 1889 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
1890 | } |
1891 | ||
c88fd863 SR |
1892 | struct ftrace_rec_iter { |
1893 | struct ftrace_page *pg; | |
1894 | int index; | |
1895 | }; | |
1896 | ||
1897 | /** | |
1898 | * ftrace_rec_iter_start, start up iterating over traced functions | |
1899 | * | |
1900 | * Returns an iterator handle that is used to iterate over all | |
1901 | * the records that represent address locations where functions | |
1902 | * are traced. | |
1903 | * | |
1904 | * May return NULL if no records are available. | |
1905 | */ | |
1906 | struct ftrace_rec_iter *ftrace_rec_iter_start(void) | |
1907 | { | |
1908 | /* | |
1909 | * We only use a single iterator. | |
1910 | * Protected by the ftrace_lock mutex. | |
1911 | */ | |
1912 | static struct ftrace_rec_iter ftrace_rec_iter; | |
1913 | struct ftrace_rec_iter *iter = &ftrace_rec_iter; | |
1914 | ||
1915 | iter->pg = ftrace_pages_start; | |
1916 | iter->index = 0; | |
1917 | ||
1918 | /* Could have empty pages */ | |
1919 | while (iter->pg && !iter->pg->index) | |
1920 | iter->pg = iter->pg->next; | |
1921 | ||
1922 | if (!iter->pg) | |
1923 | return NULL; | |
1924 | ||
1925 | return iter; | |
1926 | } | |
1927 | ||
1928 | /** | |
1929 | * ftrace_rec_iter_next, get the next record to process. | |
1930 | * @iter: The handle to the iterator. | |
1931 | * | |
1932 | * Returns the next iterator after the given iterator @iter. | |
1933 | */ | |
1934 | struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter) | |
1935 | { | |
1936 | iter->index++; | |
1937 | ||
1938 | if (iter->index >= iter->pg->index) { | |
1939 | iter->pg = iter->pg->next; | |
1940 | iter->index = 0; | |
1941 | ||
1942 | /* Could have empty pages */ | |
1943 | while (iter->pg && !iter->pg->index) | |
1944 | iter->pg = iter->pg->next; | |
1945 | } | |
1946 | ||
1947 | if (!iter->pg) | |
1948 | return NULL; | |
1949 | ||
1950 | return iter; | |
1951 | } | |
1952 | ||
1953 | /** | |
1954 | * ftrace_rec_iter_record, get the record at the iterator location | |
1955 | * @iter: The current iterator location | |
1956 | * | |
1957 | * Returns the record that the current @iter is at. | |
1958 | */ | |
1959 | struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter) | |
1960 | { | |
1961 | return &iter->pg->records[iter->index]; | |
1962 | } | |
1963 | ||
492a7ea5 | 1964 | static int |
31e88909 | 1965 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 SR |
1966 | { |
1967 | unsigned long ip; | |
593eb8a2 | 1968 | int ret; |
3c1720f0 SR |
1969 | |
1970 | ip = rec->ip; | |
1971 | ||
45a4a237 SR |
1972 | if (unlikely(ftrace_disabled)) |
1973 | return 0; | |
1974 | ||
25aac9dc | 1975 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
593eb8a2 | 1976 | if (ret) { |
31e88909 | 1977 | ftrace_bug(ret, ip); |
492a7ea5 | 1978 | return 0; |
37ad5084 | 1979 | } |
492a7ea5 | 1980 | return 1; |
3c1720f0 SR |
1981 | } |
1982 | ||
000ab691 SR |
1983 | /* |
1984 | * archs can override this function if they must do something | |
1985 | * before the modifying code is performed. | |
1986 | */ | |
1987 | int __weak ftrace_arch_code_modify_prepare(void) | |
1988 | { | |
1989 | return 0; | |
1990 | } | |
1991 | ||
1992 | /* | |
1993 | * archs can override this function if they must do something | |
1994 | * after the modifying code is performed. | |
1995 | */ | |
1996 | int __weak ftrace_arch_code_modify_post_process(void) | |
1997 | { | |
1998 | return 0; | |
1999 | } | |
2000 | ||
8ed3e2cf | 2001 | void ftrace_modify_all_code(int command) |
3d083395 | 2002 | { |
8ed3e2cf | 2003 | if (command & FTRACE_UPDATE_CALLS) |
d61f82d0 | 2004 | ftrace_replace_code(1); |
8ed3e2cf | 2005 | else if (command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
2006 | ftrace_replace_code(0); |
2007 | ||
a0d0a2a5 SR |
2008 | if (command & FTRACE_UPDATE_TRACE_FUNC) { |
2009 | function_trace_op = set_function_trace_op; | |
2010 | smp_wmb(); | |
2011 | /* If irqs are disabled, we are in stop machine */ | |
2012 | if (!irqs_disabled()) | |
2013 | smp_call_function(ftrace_sync_ipi, NULL, 1); | |
d61f82d0 | 2014 | ftrace_update_ftrace_func(ftrace_trace_function); |
a0d0a2a5 | 2015 | } |
d61f82d0 | 2016 | |
8ed3e2cf | 2017 | if (command & FTRACE_START_FUNC_RET) |
5a45cfe1 | 2018 | ftrace_enable_ftrace_graph_caller(); |
8ed3e2cf | 2019 | else if (command & FTRACE_STOP_FUNC_RET) |
5a45cfe1 | 2020 | ftrace_disable_ftrace_graph_caller(); |
8ed3e2cf SR |
2021 | } |
2022 | ||
2023 | static int __ftrace_modify_code(void *data) | |
2024 | { | |
2025 | int *command = data; | |
2026 | ||
2027 | ftrace_modify_all_code(*command); | |
5a45cfe1 | 2028 | |
d61f82d0 | 2029 | return 0; |
3d083395 SR |
2030 | } |
2031 | ||
c88fd863 SR |
2032 | /** |
2033 | * ftrace_run_stop_machine, go back to the stop machine method | |
2034 | * @command: The command to tell ftrace what to do | |
2035 | * | |
2036 | * If an arch needs to fall back to the stop machine method, the | |
2037 | * it can call this function. | |
2038 | */ | |
2039 | void ftrace_run_stop_machine(int command) | |
2040 | { | |
2041 | stop_machine(__ftrace_modify_code, &command, NULL); | |
2042 | } | |
2043 | ||
2044 | /** | |
2045 | * arch_ftrace_update_code, modify the code to trace or not trace | |
2046 | * @command: The command that needs to be done | |
2047 | * | |
2048 | * Archs can override this function if it does not need to | |
2049 | * run stop_machine() to modify code. | |
2050 | */ | |
2051 | void __weak arch_ftrace_update_code(int command) | |
2052 | { | |
2053 | ftrace_run_stop_machine(command); | |
2054 | } | |
2055 | ||
e309b41d | 2056 | static void ftrace_run_update_code(int command) |
3d083395 | 2057 | { |
000ab691 SR |
2058 | int ret; |
2059 | ||
2060 | ret = ftrace_arch_code_modify_prepare(); | |
2061 | FTRACE_WARN_ON(ret); | |
2062 | if (ret) | |
2063 | return; | |
c88fd863 SR |
2064 | /* |
2065 | * Do not call function tracer while we update the code. | |
2066 | * We are in stop machine. | |
2067 | */ | |
2068 | function_trace_stop++; | |
000ab691 | 2069 | |
c88fd863 SR |
2070 | /* |
2071 | * By default we use stop_machine() to modify the code. | |
2072 | * But archs can do what ever they want as long as it | |
2073 | * is safe. The stop_machine() is the safest, but also | |
2074 | * produces the most overhead. | |
2075 | */ | |
2076 | arch_ftrace_update_code(command); | |
2077 | ||
c88fd863 | 2078 | function_trace_stop--; |
000ab691 SR |
2079 | |
2080 | ret = ftrace_arch_code_modify_post_process(); | |
2081 | FTRACE_WARN_ON(ret); | |
3d083395 SR |
2082 | } |
2083 | ||
d61f82d0 | 2084 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 2085 | static int ftrace_start_up; |
b848914c | 2086 | static int global_start_up; |
df4fc315 SR |
2087 | |
2088 | static void ftrace_startup_enable(int command) | |
2089 | { | |
2090 | if (saved_ftrace_func != ftrace_trace_function) { | |
2091 | saved_ftrace_func = ftrace_trace_function; | |
2092 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2093 | } | |
2094 | ||
2095 | if (!command || !ftrace_enabled) | |
2096 | return; | |
2097 | ||
2098 | ftrace_run_update_code(command); | |
2099 | } | |
d61f82d0 | 2100 | |
a1cd6173 | 2101 | static int ftrace_startup(struct ftrace_ops *ops, int command) |
3d083395 | 2102 | { |
b848914c | 2103 | bool hash_enable = true; |
2940c25b | 2104 | int ret; |
b848914c | 2105 | |
4eebcc81 | 2106 | if (unlikely(ftrace_disabled)) |
a1cd6173 | 2107 | return -ENODEV; |
4eebcc81 | 2108 | |
2940c25b SRRH |
2109 | ret = __register_ftrace_function(ops); |
2110 | if (ret) | |
2111 | return ret; | |
2112 | ||
60a7ecf4 | 2113 | ftrace_start_up++; |
30fb6aa7 | 2114 | command |= FTRACE_UPDATE_CALLS; |
d61f82d0 | 2115 | |
b848914c SR |
2116 | /* ops marked global share the filter hashes */ |
2117 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { | |
2118 | ops = &global_ops; | |
2119 | /* Don't update hash if global is already set */ | |
2120 | if (global_start_up) | |
2121 | hash_enable = false; | |
2122 | global_start_up++; | |
2123 | } | |
2124 | ||
ed926f9b | 2125 | ops->flags |= FTRACE_OPS_FL_ENABLED; |
b848914c | 2126 | if (hash_enable) |
ed926f9b SR |
2127 | ftrace_hash_rec_enable(ops, 1); |
2128 | ||
df4fc315 | 2129 | ftrace_startup_enable(command); |
a1cd6173 SR |
2130 | |
2131 | return 0; | |
3d083395 SR |
2132 | } |
2133 | ||
2940c25b | 2134 | static int ftrace_shutdown(struct ftrace_ops *ops, int command) |
3d083395 | 2135 | { |
b848914c | 2136 | bool hash_disable = true; |
2940c25b | 2137 | int ret; |
b848914c | 2138 | |
4eebcc81 | 2139 | if (unlikely(ftrace_disabled)) |
2940c25b SRRH |
2140 | return -ENODEV; |
2141 | ||
2142 | ret = __unregister_ftrace_function(ops); | |
2143 | if (ret) | |
2144 | return ret; | |
4eebcc81 | 2145 | |
60a7ecf4 | 2146 | ftrace_start_up--; |
9ea1a153 FW |
2147 | /* |
2148 | * Just warn in case of unbalance, no need to kill ftrace, it's not | |
2149 | * critical but the ftrace_call callers may be never nopped again after | |
2150 | * further ftrace uses. | |
2151 | */ | |
2152 | WARN_ON_ONCE(ftrace_start_up < 0); | |
2153 | ||
b848914c SR |
2154 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) { |
2155 | ops = &global_ops; | |
2156 | global_start_up--; | |
2157 | WARN_ON_ONCE(global_start_up < 0); | |
2158 | /* Don't update hash if global still has users */ | |
2159 | if (global_start_up) { | |
2160 | WARN_ON_ONCE(!ftrace_start_up); | |
2161 | hash_disable = false; | |
2162 | } | |
2163 | } | |
2164 | ||
2165 | if (hash_disable) | |
ed926f9b SR |
2166 | ftrace_hash_rec_disable(ops, 1); |
2167 | ||
b848914c | 2168 | if (ops != &global_ops || !global_start_up) |
ed926f9b | 2169 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; |
b848914c | 2170 | |
30fb6aa7 | 2171 | command |= FTRACE_UPDATE_CALLS; |
3d083395 | 2172 | |
d61f82d0 SR |
2173 | if (saved_ftrace_func != ftrace_trace_function) { |
2174 | saved_ftrace_func = ftrace_trace_function; | |
2175 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2176 | } | |
3d083395 | 2177 | |
b6c5a8d3 SR |
2178 | if (!command || !ftrace_enabled) { |
2179 | /* | |
2180 | * If these are control ops, they still need their | |
2181 | * per_cpu field freed. Since, function tracing is | |
2182 | * not currently active, we can just free them | |
2183 | * without synchronizing all CPUs. | |
2184 | */ | |
2185 | if (ops->flags & FTRACE_OPS_FL_CONTROL) | |
2186 | control_ops_free(ops); | |
2940c25b | 2187 | return 0; |
b6c5a8d3 | 2188 | } |
d61f82d0 SR |
2189 | |
2190 | ftrace_run_update_code(command); | |
b6c5a8d3 SR |
2191 | |
2192 | /* | |
2193 | * Dynamic ops may be freed, we must make sure that all | |
2194 | * callers are done before leaving this function. | |
2195 | * The same goes for freeing the per_cpu data of the control | |
2196 | * ops. | |
2197 | * | |
2198 | * Again, normal synchronize_sched() is not good enough. | |
2199 | * We need to do a hard force of sched synchronization. | |
2200 | * This is because we use preempt_disable() to do RCU, but | |
2201 | * the function tracers can be called where RCU is not watching | |
2202 | * (like before user_exit()). We can not rely on the RCU | |
2203 | * infrastructure to do the synchronization, thus we must do it | |
2204 | * ourselves. | |
2205 | */ | |
2206 | if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_CONTROL)) { | |
2207 | schedule_on_each_cpu(ftrace_sync); | |
2208 | ||
2209 | if (ops->flags & FTRACE_OPS_FL_CONTROL) | |
2210 | control_ops_free(ops); | |
2211 | } | |
2212 | ||
2940c25b | 2213 | return 0; |
3d083395 SR |
2214 | } |
2215 | ||
e309b41d | 2216 | static void ftrace_startup_sysctl(void) |
b0fc494f | 2217 | { |
4eebcc81 SR |
2218 | if (unlikely(ftrace_disabled)) |
2219 | return; | |
2220 | ||
d61f82d0 SR |
2221 | /* Force update next time */ |
2222 | saved_ftrace_func = NULL; | |
60a7ecf4 SR |
2223 | /* ftrace_start_up is true if we want ftrace running */ |
2224 | if (ftrace_start_up) | |
30fb6aa7 | 2225 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); |
b0fc494f SR |
2226 | } |
2227 | ||
e309b41d | 2228 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 2229 | { |
4eebcc81 SR |
2230 | if (unlikely(ftrace_disabled)) |
2231 | return; | |
2232 | ||
60a7ecf4 SR |
2233 | /* ftrace_start_up is true if ftrace is running */ |
2234 | if (ftrace_start_up) | |
79e406d7 | 2235 | ftrace_run_update_code(FTRACE_DISABLE_CALLS); |
b0fc494f SR |
2236 | } |
2237 | ||
3d083395 SR |
2238 | static cycle_t ftrace_update_time; |
2239 | static unsigned long ftrace_update_cnt; | |
2240 | unsigned long ftrace_update_tot_cnt; | |
2241 | ||
f05e999f | 2242 | static inline int ops_traces_mod(struct ftrace_ops *ops) |
f7bc8b61 | 2243 | { |
f05e999f SRRH |
2244 | /* |
2245 | * Filter_hash being empty will default to trace module. | |
2246 | * But notrace hash requires a test of individual module functions. | |
2247 | */ | |
2248 | return ftrace_hash_empty(ops->filter_hash) && | |
2249 | ftrace_hash_empty(ops->notrace_hash); | |
2250 | } | |
2251 | ||
2252 | /* | |
2253 | * Check if the current ops references the record. | |
2254 | * | |
2255 | * If the ops traces all functions, then it was already accounted for. | |
2256 | * If the ops does not trace the current record function, skip it. | |
2257 | * If the ops ignores the function via notrace filter, skip it. | |
2258 | */ | |
2259 | static inline bool | |
2260 | ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec) | |
2261 | { | |
2262 | /* If ops isn't enabled, ignore it */ | |
2263 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
2264 | return 0; | |
2265 | ||
2266 | /* If ops traces all mods, we already accounted for it */ | |
2267 | if (ops_traces_mod(ops)) | |
2268 | return 0; | |
2269 | ||
2270 | /* The function must be in the filter */ | |
2271 | if (!ftrace_hash_empty(ops->filter_hash) && | |
2272 | !ftrace_lookup_ip(ops->filter_hash, rec->ip)) | |
2273 | return 0; | |
f7bc8b61 | 2274 | |
f05e999f SRRH |
2275 | /* If in notrace hash, we ignore it too */ |
2276 | if (ftrace_lookup_ip(ops->notrace_hash, rec->ip)) | |
2277 | return 0; | |
2278 | ||
2279 | return 1; | |
2280 | } | |
2281 | ||
2282 | static int referenced_filters(struct dyn_ftrace *rec) | |
2283 | { | |
2284 | struct ftrace_ops *ops; | |
2285 | int cnt = 0; | |
2286 | ||
2287 | for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) { | |
2288 | if (ops_references_rec(ops, rec)) | |
2289 | cnt++; | |
2290 | } | |
2291 | ||
2292 | return cnt; | |
f7bc8b61 SR |
2293 | } |
2294 | ||
31e88909 | 2295 | static int ftrace_update_code(struct module *mod) |
3d083395 | 2296 | { |
85ae32ae | 2297 | struct ftrace_page *pg; |
e94142a6 | 2298 | struct dyn_ftrace *p; |
f22f9a89 | 2299 | cycle_t start, stop; |
f7bc8b61 | 2300 | unsigned long ref = 0; |
f05e999f | 2301 | bool test = false; |
85ae32ae | 2302 | int i; |
f7bc8b61 SR |
2303 | |
2304 | /* | |
2305 | * When adding a module, we need to check if tracers are | |
2306 | * currently enabled and if they are set to trace all functions. | |
2307 | * If they are, we need to enable the module functions as well | |
2308 | * as update the reference counts for those function records. | |
2309 | */ | |
2310 | if (mod) { | |
2311 | struct ftrace_ops *ops; | |
2312 | ||
2313 | for (ops = ftrace_ops_list; | |
2314 | ops != &ftrace_list_end; ops = ops->next) { | |
f05e999f SRRH |
2315 | if (ops->flags & FTRACE_OPS_FL_ENABLED) { |
2316 | if (ops_traces_mod(ops)) | |
2317 | ref++; | |
2318 | else | |
2319 | test = true; | |
2320 | } | |
f7bc8b61 SR |
2321 | } |
2322 | } | |
3d083395 | 2323 | |
750ed1a4 | 2324 | start = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
2325 | ftrace_update_cnt = 0; |
2326 | ||
85ae32ae | 2327 | for (pg = ftrace_new_pgs; pg; pg = pg->next) { |
3d083395 | 2328 | |
85ae32ae | 2329 | for (i = 0; i < pg->index; i++) { |
f05e999f SRRH |
2330 | int cnt = ref; |
2331 | ||
85ae32ae SR |
2332 | /* If something went wrong, bail without enabling anything */ |
2333 | if (unlikely(ftrace_disabled)) | |
2334 | return -1; | |
f22f9a89 | 2335 | |
85ae32ae | 2336 | p = &pg->records[i]; |
f05e999f SRRH |
2337 | if (test) |
2338 | cnt += referenced_filters(p); | |
2339 | p->flags = cnt; | |
f22f9a89 | 2340 | |
85ae32ae SR |
2341 | /* |
2342 | * Do the initial record conversion from mcount jump | |
2343 | * to the NOP instructions. | |
2344 | */ | |
2345 | if (!ftrace_code_disable(mod, p)) | |
2346 | break; | |
5cb084bb | 2347 | |
85ae32ae | 2348 | ftrace_update_cnt++; |
5cb084bb | 2349 | |
85ae32ae SR |
2350 | /* |
2351 | * If the tracing is enabled, go ahead and enable the record. | |
2352 | * | |
2353 | * The reason not to enable the record immediatelly is the | |
2354 | * inherent check of ftrace_make_nop/ftrace_make_call for | |
2355 | * correct previous instructions. Making first the NOP | |
2356 | * conversion puts the module to the correct state, thus | |
2357 | * passing the ftrace_make_call check. | |
2358 | */ | |
f05e999f | 2359 | if (ftrace_start_up && cnt) { |
85ae32ae SR |
2360 | int failed = __ftrace_replace_code(p, 1); |
2361 | if (failed) | |
2362 | ftrace_bug(failed, p->ip); | |
2363 | } | |
5cb084bb | 2364 | } |
3d083395 SR |
2365 | } |
2366 | ||
85ae32ae SR |
2367 | ftrace_new_pgs = NULL; |
2368 | ||
750ed1a4 | 2369 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
2370 | ftrace_update_time = stop - start; |
2371 | ftrace_update_tot_cnt += ftrace_update_cnt; | |
2372 | ||
16444a8a ACM |
2373 | return 0; |
2374 | } | |
2375 | ||
a7900875 | 2376 | static int ftrace_allocate_records(struct ftrace_page *pg, int count) |
3c1720f0 | 2377 | { |
a7900875 | 2378 | int order; |
3c1720f0 | 2379 | int cnt; |
3c1720f0 | 2380 | |
a7900875 SR |
2381 | if (WARN_ON(!count)) |
2382 | return -EINVAL; | |
2383 | ||
2384 | order = get_count_order(DIV_ROUND_UP(count, ENTRIES_PER_PAGE)); | |
3c1720f0 SR |
2385 | |
2386 | /* | |
a7900875 SR |
2387 | * We want to fill as much as possible. No more than a page |
2388 | * may be empty. | |
3c1720f0 | 2389 | */ |
a7900875 SR |
2390 | while ((PAGE_SIZE << order) / ENTRY_SIZE >= count + ENTRIES_PER_PAGE) |
2391 | order--; | |
3c1720f0 | 2392 | |
a7900875 SR |
2393 | again: |
2394 | pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); | |
3c1720f0 | 2395 | |
a7900875 SR |
2396 | if (!pg->records) { |
2397 | /* if we can't allocate this size, try something smaller */ | |
2398 | if (!order) | |
2399 | return -ENOMEM; | |
2400 | order >>= 1; | |
2401 | goto again; | |
2402 | } | |
3c1720f0 | 2403 | |
a7900875 SR |
2404 | cnt = (PAGE_SIZE << order) / ENTRY_SIZE; |
2405 | pg->size = cnt; | |
3c1720f0 | 2406 | |
a7900875 SR |
2407 | if (cnt > count) |
2408 | cnt = count; | |
2409 | ||
2410 | return cnt; | |
2411 | } | |
2412 | ||
2413 | static struct ftrace_page * | |
2414 | ftrace_allocate_pages(unsigned long num_to_init) | |
2415 | { | |
2416 | struct ftrace_page *start_pg; | |
2417 | struct ftrace_page *pg; | |
2418 | int order; | |
2419 | int cnt; | |
2420 | ||
2421 | if (!num_to_init) | |
2422 | return 0; | |
2423 | ||
2424 | start_pg = pg = kzalloc(sizeof(*pg), GFP_KERNEL); | |
2425 | if (!pg) | |
2426 | return NULL; | |
2427 | ||
2428 | /* | |
2429 | * Try to allocate as much as possible in one continues | |
2430 | * location that fills in all of the space. We want to | |
2431 | * waste as little space as possible. | |
2432 | */ | |
2433 | for (;;) { | |
2434 | cnt = ftrace_allocate_records(pg, num_to_init); | |
2435 | if (cnt < 0) | |
2436 | goto free_pages; | |
2437 | ||
2438 | num_to_init -= cnt; | |
2439 | if (!num_to_init) | |
3c1720f0 SR |
2440 | break; |
2441 | ||
a7900875 SR |
2442 | pg->next = kzalloc(sizeof(*pg), GFP_KERNEL); |
2443 | if (!pg->next) | |
2444 | goto free_pages; | |
2445 | ||
3c1720f0 SR |
2446 | pg = pg->next; |
2447 | } | |
2448 | ||
a7900875 SR |
2449 | return start_pg; |
2450 | ||
2451 | free_pages: | |
2452 | while (start_pg) { | |
2453 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); | |
2454 | free_pages((unsigned long)pg->records, order); | |
2455 | start_pg = pg->next; | |
2456 | kfree(pg); | |
2457 | pg = start_pg; | |
2458 | } | |
2459 | pr_info("ftrace: FAILED to allocate memory for functions\n"); | |
2460 | return NULL; | |
2461 | } | |
2462 | ||
2463 | static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) | |
2464 | { | |
2465 | int cnt; | |
2466 | ||
2467 | if (!num_to_init) { | |
2468 | pr_info("ftrace: No functions to be traced?\n"); | |
2469 | return -1; | |
2470 | } | |
2471 | ||
2472 | cnt = num_to_init / ENTRIES_PER_PAGE; | |
2473 | pr_info("ftrace: allocating %ld entries in %d pages\n", | |
2474 | num_to_init, cnt + 1); | |
2475 | ||
3c1720f0 SR |
2476 | return 0; |
2477 | } | |
2478 | ||
5072c59f SR |
2479 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ |
2480 | ||
2481 | struct ftrace_iterator { | |
98c4fd04 | 2482 | loff_t pos; |
4aeb6967 SR |
2483 | loff_t func_pos; |
2484 | struct ftrace_page *pg; | |
2485 | struct dyn_ftrace *func; | |
2486 | struct ftrace_func_probe *probe; | |
2487 | struct trace_parser parser; | |
1cf41dd7 | 2488 | struct ftrace_hash *hash; |
33dc9b12 | 2489 | struct ftrace_ops *ops; |
4aeb6967 SR |
2490 | int hidx; |
2491 | int idx; | |
2492 | unsigned flags; | |
5072c59f SR |
2493 | }; |
2494 | ||
8fc0c701 | 2495 | static void * |
4aeb6967 | 2496 | t_hash_next(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
2497 | { |
2498 | struct ftrace_iterator *iter = m->private; | |
4aeb6967 | 2499 | struct hlist_node *hnd = NULL; |
8fc0c701 SR |
2500 | struct hlist_head *hhd; |
2501 | ||
8fc0c701 | 2502 | (*pos)++; |
98c4fd04 | 2503 | iter->pos = *pos; |
8fc0c701 | 2504 | |
4aeb6967 SR |
2505 | if (iter->probe) |
2506 | hnd = &iter->probe->node; | |
8fc0c701 SR |
2507 | retry: |
2508 | if (iter->hidx >= FTRACE_FUNC_HASHSIZE) | |
2509 | return NULL; | |
2510 | ||
2511 | hhd = &ftrace_func_hash[iter->hidx]; | |
2512 | ||
2513 | if (hlist_empty(hhd)) { | |
2514 | iter->hidx++; | |
2515 | hnd = NULL; | |
2516 | goto retry; | |
2517 | } | |
2518 | ||
2519 | if (!hnd) | |
2520 | hnd = hhd->first; | |
2521 | else { | |
2522 | hnd = hnd->next; | |
2523 | if (!hnd) { | |
2524 | iter->hidx++; | |
2525 | goto retry; | |
2526 | } | |
2527 | } | |
2528 | ||
4aeb6967 SR |
2529 | if (WARN_ON_ONCE(!hnd)) |
2530 | return NULL; | |
2531 | ||
2532 | iter->probe = hlist_entry(hnd, struct ftrace_func_probe, node); | |
2533 | ||
2534 | return iter; | |
8fc0c701 SR |
2535 | } |
2536 | ||
2537 | static void *t_hash_start(struct seq_file *m, loff_t *pos) | |
2538 | { | |
2539 | struct ftrace_iterator *iter = m->private; | |
2540 | void *p = NULL; | |
d82d6244 LZ |
2541 | loff_t l; |
2542 | ||
69a3083c SR |
2543 | if (!(iter->flags & FTRACE_ITER_DO_HASH)) |
2544 | return NULL; | |
2545 | ||
2bccfffd SR |
2546 | if (iter->func_pos > *pos) |
2547 | return NULL; | |
8fc0c701 | 2548 | |
d82d6244 | 2549 | iter->hidx = 0; |
2bccfffd | 2550 | for (l = 0; l <= (*pos - iter->func_pos); ) { |
4aeb6967 | 2551 | p = t_hash_next(m, &l); |
d82d6244 LZ |
2552 | if (!p) |
2553 | break; | |
2554 | } | |
4aeb6967 SR |
2555 | if (!p) |
2556 | return NULL; | |
2557 | ||
98c4fd04 SR |
2558 | /* Only set this if we have an item */ |
2559 | iter->flags |= FTRACE_ITER_HASH; | |
2560 | ||
4aeb6967 | 2561 | return iter; |
8fc0c701 SR |
2562 | } |
2563 | ||
4aeb6967 SR |
2564 | static int |
2565 | t_hash_show(struct seq_file *m, struct ftrace_iterator *iter) | |
8fc0c701 | 2566 | { |
b6887d79 | 2567 | struct ftrace_func_probe *rec; |
8fc0c701 | 2568 | |
4aeb6967 SR |
2569 | rec = iter->probe; |
2570 | if (WARN_ON_ONCE(!rec)) | |
2571 | return -EIO; | |
8fc0c701 | 2572 | |
809dcf29 SR |
2573 | if (rec->ops->print) |
2574 | return rec->ops->print(m, rec->ip, rec->ops, rec->data); | |
2575 | ||
b375a11a | 2576 | seq_printf(m, "%ps:%ps", (void *)rec->ip, (void *)rec->ops->func); |
8fc0c701 SR |
2577 | |
2578 | if (rec->data) | |
2579 | seq_printf(m, ":%p", rec->data); | |
2580 | seq_putc(m, '\n'); | |
2581 | ||
2582 | return 0; | |
2583 | } | |
2584 | ||
e309b41d | 2585 | static void * |
5072c59f SR |
2586 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2587 | { | |
2588 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 2589 | struct ftrace_ops *ops = iter->ops; |
5072c59f SR |
2590 | struct dyn_ftrace *rec = NULL; |
2591 | ||
45a4a237 SR |
2592 | if (unlikely(ftrace_disabled)) |
2593 | return NULL; | |
2594 | ||
8fc0c701 | 2595 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 2596 | return t_hash_next(m, pos); |
8fc0c701 | 2597 | |
5072c59f | 2598 | (*pos)++; |
1106b699 | 2599 | iter->pos = iter->func_pos = *pos; |
5072c59f | 2600 | |
0c75a3ed | 2601 | if (iter->flags & FTRACE_ITER_PRINTALL) |
57c072c7 | 2602 | return t_hash_start(m, pos); |
0c75a3ed | 2603 | |
5072c59f SR |
2604 | retry: |
2605 | if (iter->idx >= iter->pg->index) { | |
2606 | if (iter->pg->next) { | |
2607 | iter->pg = iter->pg->next; | |
2608 | iter->idx = 0; | |
2609 | goto retry; | |
2610 | } | |
2611 | } else { | |
2612 | rec = &iter->pg->records[iter->idx++]; | |
32082309 | 2613 | if (((iter->flags & FTRACE_ITER_FILTER) && |
f45948e8 | 2614 | !(ftrace_lookup_ip(ops->filter_hash, rec->ip))) || |
0183fb1c | 2615 | |
41c52c0d | 2616 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
647bcd03 SR |
2617 | !ftrace_lookup_ip(ops->notrace_hash, rec->ip)) || |
2618 | ||
2619 | ((iter->flags & FTRACE_ITER_ENABLED) && | |
23ea9c4d | 2620 | !(rec->flags & FTRACE_FL_ENABLED))) { |
647bcd03 | 2621 | |
5072c59f SR |
2622 | rec = NULL; |
2623 | goto retry; | |
2624 | } | |
2625 | } | |
2626 | ||
4aeb6967 | 2627 | if (!rec) |
57c072c7 | 2628 | return t_hash_start(m, pos); |
4aeb6967 SR |
2629 | |
2630 | iter->func = rec; | |
2631 | ||
2632 | return iter; | |
5072c59f SR |
2633 | } |
2634 | ||
98c4fd04 SR |
2635 | static void reset_iter_read(struct ftrace_iterator *iter) |
2636 | { | |
2637 | iter->pos = 0; | |
2638 | iter->func_pos = 0; | |
70f77b3f | 2639 | iter->flags &= ~(FTRACE_ITER_PRINTALL | FTRACE_ITER_HASH); |
5072c59f SR |
2640 | } |
2641 | ||
2642 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2643 | { | |
2644 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 2645 | struct ftrace_ops *ops = iter->ops; |
5072c59f | 2646 | void *p = NULL; |
694ce0a5 | 2647 | loff_t l; |
5072c59f | 2648 | |
8fc0c701 | 2649 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
2650 | |
2651 | if (unlikely(ftrace_disabled)) | |
2652 | return NULL; | |
2653 | ||
98c4fd04 SR |
2654 | /* |
2655 | * If an lseek was done, then reset and start from beginning. | |
2656 | */ | |
2657 | if (*pos < iter->pos) | |
2658 | reset_iter_read(iter); | |
2659 | ||
0c75a3ed SR |
2660 | /* |
2661 | * For set_ftrace_filter reading, if we have the filter | |
2662 | * off, we can short cut and just print out that all | |
2663 | * functions are enabled. | |
2664 | */ | |
06a51d93 SR |
2665 | if (iter->flags & FTRACE_ITER_FILTER && |
2666 | ftrace_hash_empty(ops->filter_hash)) { | |
0c75a3ed | 2667 | if (*pos > 0) |
8fc0c701 | 2668 | return t_hash_start(m, pos); |
0c75a3ed | 2669 | iter->flags |= FTRACE_ITER_PRINTALL; |
df091625 CW |
2670 | /* reset in case of seek/pread */ |
2671 | iter->flags &= ~FTRACE_ITER_HASH; | |
0c75a3ed SR |
2672 | return iter; |
2673 | } | |
2674 | ||
8fc0c701 SR |
2675 | if (iter->flags & FTRACE_ITER_HASH) |
2676 | return t_hash_start(m, pos); | |
2677 | ||
98c4fd04 SR |
2678 | /* |
2679 | * Unfortunately, we need to restart at ftrace_pages_start | |
2680 | * every time we let go of the ftrace_mutex. This is because | |
2681 | * those pointers can change without the lock. | |
2682 | */ | |
694ce0a5 LZ |
2683 | iter->pg = ftrace_pages_start; |
2684 | iter->idx = 0; | |
2685 | for (l = 0; l <= *pos; ) { | |
2686 | p = t_next(m, p, &l); | |
2687 | if (!p) | |
2688 | break; | |
50cdaf08 | 2689 | } |
5821e1b7 | 2690 | |
69a3083c SR |
2691 | if (!p) |
2692 | return t_hash_start(m, pos); | |
4aeb6967 SR |
2693 | |
2694 | return iter; | |
5072c59f SR |
2695 | } |
2696 | ||
2697 | static void t_stop(struct seq_file *m, void *p) | |
2698 | { | |
8fc0c701 | 2699 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
2700 | } |
2701 | ||
2702 | static int t_show(struct seq_file *m, void *v) | |
2703 | { | |
0c75a3ed | 2704 | struct ftrace_iterator *iter = m->private; |
4aeb6967 | 2705 | struct dyn_ftrace *rec; |
5072c59f | 2706 | |
8fc0c701 | 2707 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 2708 | return t_hash_show(m, iter); |
8fc0c701 | 2709 | |
0c75a3ed SR |
2710 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
2711 | seq_printf(m, "#### all functions enabled ####\n"); | |
2712 | return 0; | |
2713 | } | |
2714 | ||
4aeb6967 SR |
2715 | rec = iter->func; |
2716 | ||
5072c59f SR |
2717 | if (!rec) |
2718 | return 0; | |
2719 | ||
647bcd03 SR |
2720 | seq_printf(m, "%ps", (void *)rec->ip); |
2721 | if (iter->flags & FTRACE_ITER_ENABLED) | |
08f6fba5 SR |
2722 | seq_printf(m, " (%ld)%s", |
2723 | rec->flags & ~FTRACE_FL_MASK, | |
2724 | rec->flags & FTRACE_FL_REGS ? " R" : ""); | |
647bcd03 | 2725 | seq_printf(m, "\n"); |
5072c59f SR |
2726 | |
2727 | return 0; | |
2728 | } | |
2729 | ||
88e9d34c | 2730 | static const struct seq_operations show_ftrace_seq_ops = { |
5072c59f SR |
2731 | .start = t_start, |
2732 | .next = t_next, | |
2733 | .stop = t_stop, | |
2734 | .show = t_show, | |
2735 | }; | |
2736 | ||
e309b41d | 2737 | static int |
5072c59f SR |
2738 | ftrace_avail_open(struct inode *inode, struct file *file) |
2739 | { | |
2740 | struct ftrace_iterator *iter; | |
5072c59f | 2741 | |
4eebcc81 SR |
2742 | if (unlikely(ftrace_disabled)) |
2743 | return -ENODEV; | |
2744 | ||
50e18b94 JO |
2745 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
2746 | if (iter) { | |
2747 | iter->pg = ftrace_pages_start; | |
2748 | iter->ops = &global_ops; | |
4bf39a94 | 2749 | } |
5072c59f | 2750 | |
50e18b94 | 2751 | return iter ? 0 : -ENOMEM; |
5072c59f SR |
2752 | } |
2753 | ||
647bcd03 SR |
2754 | static int |
2755 | ftrace_enabled_open(struct inode *inode, struct file *file) | |
2756 | { | |
2757 | struct ftrace_iterator *iter; | |
647bcd03 SR |
2758 | |
2759 | if (unlikely(ftrace_disabled)) | |
2760 | return -ENODEV; | |
2761 | ||
50e18b94 JO |
2762 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
2763 | if (iter) { | |
2764 | iter->pg = ftrace_pages_start; | |
2765 | iter->flags = FTRACE_ITER_ENABLED; | |
2766 | iter->ops = &global_ops; | |
647bcd03 SR |
2767 | } |
2768 | ||
50e18b94 | 2769 | return iter ? 0 : -ENOMEM; |
647bcd03 SR |
2770 | } |
2771 | ||
1cf41dd7 | 2772 | static void ftrace_filter_reset(struct ftrace_hash *hash) |
5072c59f | 2773 | { |
52baf119 | 2774 | mutex_lock(&ftrace_lock); |
1cf41dd7 | 2775 | ftrace_hash_clear(hash); |
52baf119 | 2776 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
2777 | } |
2778 | ||
fc13cb0c SR |
2779 | /** |
2780 | * ftrace_regex_open - initialize function tracer filter files | |
2781 | * @ops: The ftrace_ops that hold the hash filters | |
2782 | * @flag: The type of filter to process | |
2783 | * @inode: The inode, usually passed in to your open routine | |
2784 | * @file: The file, usually passed in to your open routine | |
2785 | * | |
2786 | * ftrace_regex_open() initializes the filter files for the | |
2787 | * @ops. Depending on @flag it may process the filter hash or | |
2788 | * the notrace hash of @ops. With this called from the open | |
2789 | * routine, you can use ftrace_filter_write() for the write | |
2790 | * routine if @flag has FTRACE_ITER_FILTER set, or | |
2791 | * ftrace_notrace_write() if @flag has FTRACE_ITER_NOTRACE set. | |
7f49ef69 | 2792 | * ftrace_filter_lseek() should be used as the lseek routine, and |
fc13cb0c SR |
2793 | * release must call ftrace_regex_release(). |
2794 | */ | |
2795 | int | |
f45948e8 | 2796 | ftrace_regex_open(struct ftrace_ops *ops, int flag, |
1cf41dd7 | 2797 | struct inode *inode, struct file *file) |
5072c59f SR |
2798 | { |
2799 | struct ftrace_iterator *iter; | |
f45948e8 | 2800 | struct ftrace_hash *hash; |
5072c59f SR |
2801 | int ret = 0; |
2802 | ||
f04f24fb MH |
2803 | ftrace_ops_init(ops); |
2804 | ||
4eebcc81 SR |
2805 | if (unlikely(ftrace_disabled)) |
2806 | return -ENODEV; | |
2807 | ||
5072c59f SR |
2808 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
2809 | if (!iter) | |
2810 | return -ENOMEM; | |
2811 | ||
689fd8b6 | 2812 | if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) { |
2813 | kfree(iter); | |
2814 | return -ENOMEM; | |
2815 | } | |
2816 | ||
3f2367ba MH |
2817 | iter->ops = ops; |
2818 | iter->flags = flag; | |
2819 | ||
2820 | mutex_lock(&ops->regex_lock); | |
2821 | ||
f45948e8 SR |
2822 | if (flag & FTRACE_ITER_NOTRACE) |
2823 | hash = ops->notrace_hash; | |
2824 | else | |
2825 | hash = ops->filter_hash; | |
2826 | ||
33dc9b12 | 2827 | if (file->f_mode & FMODE_WRITE) { |
33dc9b12 | 2828 | iter->hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash); |
33dc9b12 SR |
2829 | if (!iter->hash) { |
2830 | trace_parser_put(&iter->parser); | |
2831 | kfree(iter); | |
3f2367ba MH |
2832 | ret = -ENOMEM; |
2833 | goto out_unlock; | |
33dc9b12 SR |
2834 | } |
2835 | } | |
1cf41dd7 | 2836 | |
5072c59f | 2837 | if ((file->f_mode & FMODE_WRITE) && |
8650ae32 | 2838 | (file->f_flags & O_TRUNC)) |
33dc9b12 | 2839 | ftrace_filter_reset(iter->hash); |
5072c59f SR |
2840 | |
2841 | if (file->f_mode & FMODE_READ) { | |
2842 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
2843 | |
2844 | ret = seq_open(file, &show_ftrace_seq_ops); | |
2845 | if (!ret) { | |
2846 | struct seq_file *m = file->private_data; | |
2847 | m->private = iter; | |
79fe249c | 2848 | } else { |
33dc9b12 SR |
2849 | /* Failed */ |
2850 | free_ftrace_hash(iter->hash); | |
79fe249c | 2851 | trace_parser_put(&iter->parser); |
5072c59f | 2852 | kfree(iter); |
79fe249c | 2853 | } |
5072c59f SR |
2854 | } else |
2855 | file->private_data = iter; | |
3f2367ba MH |
2856 | |
2857 | out_unlock: | |
f04f24fb | 2858 | mutex_unlock(&ops->regex_lock); |
5072c59f SR |
2859 | |
2860 | return ret; | |
2861 | } | |
2862 | ||
41c52c0d SR |
2863 | static int |
2864 | ftrace_filter_open(struct inode *inode, struct file *file) | |
2865 | { | |
69a3083c SR |
2866 | return ftrace_regex_open(&global_ops, |
2867 | FTRACE_ITER_FILTER | FTRACE_ITER_DO_HASH, | |
2868 | inode, file); | |
41c52c0d SR |
2869 | } |
2870 | ||
2871 | static int | |
2872 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
2873 | { | |
f45948e8 | 2874 | return ftrace_regex_open(&global_ops, FTRACE_ITER_NOTRACE, |
1cf41dd7 | 2875 | inode, file); |
41c52c0d SR |
2876 | } |
2877 | ||
64e7c440 | 2878 | static int ftrace_match(char *str, char *regex, int len, int type) |
9f4801e3 | 2879 | { |
9f4801e3 | 2880 | int matched = 0; |
751e9983 | 2881 | int slen; |
9f4801e3 | 2882 | |
9f4801e3 SR |
2883 | switch (type) { |
2884 | case MATCH_FULL: | |
2885 | if (strcmp(str, regex) == 0) | |
2886 | matched = 1; | |
2887 | break; | |
2888 | case MATCH_FRONT_ONLY: | |
2889 | if (strncmp(str, regex, len) == 0) | |
2890 | matched = 1; | |
2891 | break; | |
2892 | case MATCH_MIDDLE_ONLY: | |
2893 | if (strstr(str, regex)) | |
2894 | matched = 1; | |
2895 | break; | |
2896 | case MATCH_END_ONLY: | |
751e9983 LZ |
2897 | slen = strlen(str); |
2898 | if (slen >= len && memcmp(str + slen - len, regex, len) == 0) | |
9f4801e3 SR |
2899 | matched = 1; |
2900 | break; | |
2901 | } | |
2902 | ||
2903 | return matched; | |
2904 | } | |
2905 | ||
b448c4e3 | 2906 | static int |
1cf41dd7 | 2907 | enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int not) |
996e87be | 2908 | { |
b448c4e3 | 2909 | struct ftrace_func_entry *entry; |
b448c4e3 SR |
2910 | int ret = 0; |
2911 | ||
1cf41dd7 SR |
2912 | entry = ftrace_lookup_ip(hash, rec->ip); |
2913 | if (not) { | |
2914 | /* Do nothing if it doesn't exist */ | |
2915 | if (!entry) | |
2916 | return 0; | |
b448c4e3 | 2917 | |
33dc9b12 | 2918 | free_hash_entry(hash, entry); |
1cf41dd7 SR |
2919 | } else { |
2920 | /* Do nothing if it exists */ | |
2921 | if (entry) | |
2922 | return 0; | |
b448c4e3 | 2923 | |
1cf41dd7 | 2924 | ret = add_hash_entry(hash, rec->ip); |
b448c4e3 SR |
2925 | } |
2926 | return ret; | |
996e87be SR |
2927 | } |
2928 | ||
64e7c440 | 2929 | static int |
b9df92d2 SR |
2930 | ftrace_match_record(struct dyn_ftrace *rec, char *mod, |
2931 | char *regex, int len, int type) | |
64e7c440 SR |
2932 | { |
2933 | char str[KSYM_SYMBOL_LEN]; | |
b9df92d2 SR |
2934 | char *modname; |
2935 | ||
2936 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); | |
2937 | ||
2938 | if (mod) { | |
2939 | /* module lookup requires matching the module */ | |
2940 | if (!modname || strcmp(modname, mod)) | |
2941 | return 0; | |
2942 | ||
2943 | /* blank search means to match all funcs in the mod */ | |
2944 | if (!len) | |
2945 | return 1; | |
2946 | } | |
64e7c440 | 2947 | |
64e7c440 SR |
2948 | return ftrace_match(str, regex, len, type); |
2949 | } | |
2950 | ||
1cf41dd7 SR |
2951 | static int |
2952 | match_records(struct ftrace_hash *hash, char *buff, | |
2953 | int len, char *mod, int not) | |
9f4801e3 | 2954 | { |
b9df92d2 | 2955 | unsigned search_len = 0; |
9f4801e3 SR |
2956 | struct ftrace_page *pg; |
2957 | struct dyn_ftrace *rec; | |
b9df92d2 SR |
2958 | int type = MATCH_FULL; |
2959 | char *search = buff; | |
311d16da | 2960 | int found = 0; |
b448c4e3 | 2961 | int ret; |
9f4801e3 | 2962 | |
b9df92d2 SR |
2963 | if (len) { |
2964 | type = filter_parse_regex(buff, len, &search, ¬); | |
2965 | search_len = strlen(search); | |
2966 | } | |
9f4801e3 | 2967 | |
52baf119 | 2968 | mutex_lock(&ftrace_lock); |
265c831c | 2969 | |
b9df92d2 SR |
2970 | if (unlikely(ftrace_disabled)) |
2971 | goto out_unlock; | |
9f4801e3 | 2972 | |
265c831c | 2973 | do_for_each_ftrace_rec(pg, rec) { |
b9df92d2 | 2974 | if (ftrace_match_record(rec, mod, search, search_len, type)) { |
1cf41dd7 | 2975 | ret = enter_record(hash, rec, not); |
b448c4e3 SR |
2976 | if (ret < 0) { |
2977 | found = ret; | |
2978 | goto out_unlock; | |
2979 | } | |
311d16da | 2980 | found = 1; |
265c831c SR |
2981 | } |
2982 | } while_for_each_ftrace_rec(); | |
b9df92d2 | 2983 | out_unlock: |
52baf119 | 2984 | mutex_unlock(&ftrace_lock); |
311d16da LZ |
2985 | |
2986 | return found; | |
5072c59f SR |
2987 | } |
2988 | ||
64e7c440 | 2989 | static int |
1cf41dd7 | 2990 | ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) |
64e7c440 | 2991 | { |
1cf41dd7 | 2992 | return match_records(hash, buff, len, NULL, 0); |
64e7c440 SR |
2993 | } |
2994 | ||
1cf41dd7 SR |
2995 | static int |
2996 | ftrace_match_module_records(struct ftrace_hash *hash, char *buff, char *mod) | |
64e7c440 | 2997 | { |
64e7c440 | 2998 | int not = 0; |
6a24a244 | 2999 | |
64e7c440 SR |
3000 | /* blank or '*' mean the same */ |
3001 | if (strcmp(buff, "*") == 0) | |
3002 | buff[0] = 0; | |
3003 | ||
3004 | /* handle the case of 'dont filter this module' */ | |
3005 | if (strcmp(buff, "!") == 0 || strcmp(buff, "!*") == 0) { | |
3006 | buff[0] = 0; | |
3007 | not = 1; | |
3008 | } | |
3009 | ||
1cf41dd7 | 3010 | return match_records(hash, buff, strlen(buff), mod, not); |
64e7c440 SR |
3011 | } |
3012 | ||
f6180773 SR |
3013 | /* |
3014 | * We register the module command as a template to show others how | |
3015 | * to register the a command as well. | |
3016 | */ | |
3017 | ||
3018 | static int | |
43dd61c9 SR |
3019 | ftrace_mod_callback(struct ftrace_hash *hash, |
3020 | char *func, char *cmd, char *param, int enable) | |
f6180773 SR |
3021 | { |
3022 | char *mod; | |
b448c4e3 | 3023 | int ret = -EINVAL; |
f6180773 SR |
3024 | |
3025 | /* | |
3026 | * cmd == 'mod' because we only registered this func | |
3027 | * for the 'mod' ftrace_func_command. | |
3028 | * But if you register one func with multiple commands, | |
3029 | * you can tell which command was used by the cmd | |
3030 | * parameter. | |
3031 | */ | |
3032 | ||
3033 | /* we must have a module name */ | |
3034 | if (!param) | |
b448c4e3 | 3035 | return ret; |
f6180773 SR |
3036 | |
3037 | mod = strsep(¶m, ":"); | |
3038 | if (!strlen(mod)) | |
b448c4e3 | 3039 | return ret; |
f6180773 | 3040 | |
1cf41dd7 | 3041 | ret = ftrace_match_module_records(hash, func, mod); |
b448c4e3 SR |
3042 | if (!ret) |
3043 | ret = -EINVAL; | |
3044 | if (ret < 0) | |
3045 | return ret; | |
3046 | ||
3047 | return 0; | |
f6180773 SR |
3048 | } |
3049 | ||
3050 | static struct ftrace_func_command ftrace_mod_cmd = { | |
3051 | .name = "mod", | |
3052 | .func = ftrace_mod_callback, | |
3053 | }; | |
3054 | ||
3055 | static int __init ftrace_mod_cmd_init(void) | |
3056 | { | |
3057 | return register_ftrace_command(&ftrace_mod_cmd); | |
3058 | } | |
6f415672 | 3059 | core_initcall(ftrace_mod_cmd_init); |
f6180773 | 3060 | |
2f5f6ad9 | 3061 | static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 3062 | struct ftrace_ops *op, struct pt_regs *pt_regs) |
59df055f | 3063 | { |
b6887d79 | 3064 | struct ftrace_func_probe *entry; |
59df055f | 3065 | struct hlist_head *hhd; |
59df055f | 3066 | unsigned long key; |
59df055f SR |
3067 | |
3068 | key = hash_long(ip, FTRACE_HASH_BITS); | |
3069 | ||
3070 | hhd = &ftrace_func_hash[key]; | |
3071 | ||
3072 | if (hlist_empty(hhd)) | |
3073 | return; | |
3074 | ||
3075 | /* | |
3076 | * Disable preemption for these calls to prevent a RCU grace | |
3077 | * period. This syncs the hash iteration and freeing of items | |
3078 | * on the hash. rcu_read_lock is too dangerous here. | |
3079 | */ | |
5168ae50 | 3080 | preempt_disable_notrace(); |
1bb539ca | 3081 | hlist_for_each_entry_rcu_notrace(entry, hhd, node) { |
59df055f SR |
3082 | if (entry->ip == ip) |
3083 | entry->ops->func(ip, parent_ip, &entry->data); | |
3084 | } | |
5168ae50 | 3085 | preempt_enable_notrace(); |
59df055f SR |
3086 | } |
3087 | ||
b6887d79 | 3088 | static struct ftrace_ops trace_probe_ops __read_mostly = |
59df055f | 3089 | { |
fb9fb015 | 3090 | .func = function_trace_probe_call, |
f04f24fb MH |
3091 | .flags = FTRACE_OPS_FL_INITIALIZED, |
3092 | INIT_REGEX_LOCK(trace_probe_ops) | |
59df055f SR |
3093 | }; |
3094 | ||
b6887d79 | 3095 | static int ftrace_probe_registered; |
59df055f | 3096 | |
b6887d79 | 3097 | static void __enable_ftrace_function_probe(void) |
59df055f | 3098 | { |
b848914c | 3099 | int ret; |
59df055f SR |
3100 | int i; |
3101 | ||
19dd603e SRRH |
3102 | if (ftrace_probe_registered) { |
3103 | /* still need to update the function call sites */ | |
3104 | if (ftrace_enabled) | |
3105 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); | |
59df055f | 3106 | return; |
19dd603e | 3107 | } |
59df055f SR |
3108 | |
3109 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
3110 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3111 | if (hhd->first) | |
3112 | break; | |
3113 | } | |
3114 | /* Nothing registered? */ | |
3115 | if (i == FTRACE_FUNC_HASHSIZE) | |
3116 | return; | |
3117 | ||
2940c25b | 3118 | ret = ftrace_startup(&trace_probe_ops, 0); |
b848914c | 3119 | |
b6887d79 | 3120 | ftrace_probe_registered = 1; |
59df055f SR |
3121 | } |
3122 | ||
b6887d79 | 3123 | static void __disable_ftrace_function_probe(void) |
59df055f SR |
3124 | { |
3125 | int i; | |
3126 | ||
b6887d79 | 3127 | if (!ftrace_probe_registered) |
59df055f SR |
3128 | return; |
3129 | ||
3130 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
3131 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3132 | if (hhd->first) | |
3133 | return; | |
3134 | } | |
3135 | ||
3136 | /* no more funcs left */ | |
2940c25b | 3137 | ftrace_shutdown(&trace_probe_ops, 0); |
b848914c | 3138 | |
b6887d79 | 3139 | ftrace_probe_registered = 0; |
59df055f SR |
3140 | } |
3141 | ||
3142 | ||
7818b388 | 3143 | static void ftrace_free_entry(struct ftrace_func_probe *entry) |
59df055f | 3144 | { |
59df055f | 3145 | if (entry->ops->free) |
e67efb93 | 3146 | entry->ops->free(entry->ops, entry->ip, &entry->data); |
59df055f SR |
3147 | kfree(entry); |
3148 | } | |
3149 | ||
59df055f | 3150 | int |
b6887d79 | 3151 | register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3152 | void *data) |
3153 | { | |
b6887d79 | 3154 | struct ftrace_func_probe *entry; |
e1df4cb6 SRRH |
3155 | struct ftrace_hash **orig_hash = &trace_probe_ops.filter_hash; |
3156 | struct ftrace_hash *hash; | |
59df055f SR |
3157 | struct ftrace_page *pg; |
3158 | struct dyn_ftrace *rec; | |
59df055f | 3159 | int type, len, not; |
6a24a244 | 3160 | unsigned long key; |
59df055f SR |
3161 | int count = 0; |
3162 | char *search; | |
e1df4cb6 | 3163 | int ret; |
59df055f | 3164 | |
3f6fe06d | 3165 | type = filter_parse_regex(glob, strlen(glob), &search, ¬); |
59df055f SR |
3166 | len = strlen(search); |
3167 | ||
b6887d79 | 3168 | /* we do not support '!' for function probes */ |
59df055f SR |
3169 | if (WARN_ON(not)) |
3170 | return -EINVAL; | |
3171 | ||
3f2367ba | 3172 | mutex_lock(&trace_probe_ops.regex_lock); |
59df055f | 3173 | |
e1df4cb6 SRRH |
3174 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); |
3175 | if (!hash) { | |
3176 | count = -ENOMEM; | |
5ae0bf59 | 3177 | goto out; |
e1df4cb6 SRRH |
3178 | } |
3179 | ||
3180 | if (unlikely(ftrace_disabled)) { | |
3181 | count = -ENODEV; | |
5ae0bf59 | 3182 | goto out; |
e1df4cb6 | 3183 | } |
59df055f | 3184 | |
5ae0bf59 SRRH |
3185 | mutex_lock(&ftrace_lock); |
3186 | ||
45a4a237 | 3187 | do_for_each_ftrace_rec(pg, rec) { |
59df055f | 3188 | |
b9df92d2 | 3189 | if (!ftrace_match_record(rec, NULL, search, len, type)) |
59df055f SR |
3190 | continue; |
3191 | ||
3192 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
3193 | if (!entry) { | |
b6887d79 | 3194 | /* If we did not process any, then return error */ |
59df055f SR |
3195 | if (!count) |
3196 | count = -ENOMEM; | |
3197 | goto out_unlock; | |
3198 | } | |
3199 | ||
3200 | count++; | |
3201 | ||
3202 | entry->data = data; | |
3203 | ||
3204 | /* | |
3205 | * The caller might want to do something special | |
3206 | * for each function we find. We call the callback | |
3207 | * to give the caller an opportunity to do so. | |
3208 | */ | |
e67efb93 SRRH |
3209 | if (ops->init) { |
3210 | if (ops->init(ops, rec->ip, &entry->data) < 0) { | |
59df055f SR |
3211 | /* caller does not like this func */ |
3212 | kfree(entry); | |
3213 | continue; | |
3214 | } | |
3215 | } | |
3216 | ||
e1df4cb6 SRRH |
3217 | ret = enter_record(hash, rec, 0); |
3218 | if (ret < 0) { | |
3219 | kfree(entry); | |
3220 | count = ret; | |
3221 | goto out_unlock; | |
3222 | } | |
3223 | ||
59df055f SR |
3224 | entry->ops = ops; |
3225 | entry->ip = rec->ip; | |
3226 | ||
3227 | key = hash_long(entry->ip, FTRACE_HASH_BITS); | |
3228 | hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]); | |
3229 | ||
3230 | } while_for_each_ftrace_rec(); | |
e1df4cb6 SRRH |
3231 | |
3232 | ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash); | |
3233 | if (ret < 0) | |
3234 | count = ret; | |
3235 | ||
b6887d79 | 3236 | __enable_ftrace_function_probe(); |
59df055f SR |
3237 | |
3238 | out_unlock: | |
5ae0bf59 SRRH |
3239 | mutex_unlock(&ftrace_lock); |
3240 | out: | |
3f2367ba | 3241 | mutex_unlock(&trace_probe_ops.regex_lock); |
e1df4cb6 | 3242 | free_ftrace_hash(hash); |
59df055f SR |
3243 | |
3244 | return count; | |
3245 | } | |
3246 | ||
3247 | enum { | |
b6887d79 SR |
3248 | PROBE_TEST_FUNC = 1, |
3249 | PROBE_TEST_DATA = 2 | |
59df055f SR |
3250 | }; |
3251 | ||
3252 | static void | |
b6887d79 | 3253 | __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3254 | void *data, int flags) |
3255 | { | |
e1df4cb6 | 3256 | struct ftrace_func_entry *rec_entry; |
b6887d79 | 3257 | struct ftrace_func_probe *entry; |
7818b388 | 3258 | struct ftrace_func_probe *p; |
e1df4cb6 | 3259 | struct ftrace_hash **orig_hash = &trace_probe_ops.filter_hash; |
7818b388 | 3260 | struct list_head free_list; |
e1df4cb6 | 3261 | struct ftrace_hash *hash; |
b67bfe0d | 3262 | struct hlist_node *tmp; |
59df055f SR |
3263 | char str[KSYM_SYMBOL_LEN]; |
3264 | int type = MATCH_FULL; | |
3265 | int i, len = 0; | |
3266 | char *search; | |
3267 | ||
b36461da | 3268 | if (glob && (strcmp(glob, "*") == 0 || !strlen(glob))) |
59df055f | 3269 | glob = NULL; |
b36461da | 3270 | else if (glob) { |
59df055f SR |
3271 | int not; |
3272 | ||
3f6fe06d | 3273 | type = filter_parse_regex(glob, strlen(glob), &search, ¬); |
59df055f SR |
3274 | len = strlen(search); |
3275 | ||
b6887d79 | 3276 | /* we do not support '!' for function probes */ |
59df055f SR |
3277 | if (WARN_ON(not)) |
3278 | return; | |
3279 | } | |
3280 | ||
3f2367ba | 3281 | mutex_lock(&trace_probe_ops.regex_lock); |
e1df4cb6 SRRH |
3282 | |
3283 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
3284 | if (!hash) | |
3285 | /* Hmm, should report this somehow */ | |
3286 | goto out_unlock; | |
3287 | ||
7818b388 SRRH |
3288 | INIT_LIST_HEAD(&free_list); |
3289 | ||
59df055f SR |
3290 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { |
3291 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3292 | ||
b67bfe0d | 3293 | hlist_for_each_entry_safe(entry, tmp, hhd, node) { |
59df055f SR |
3294 | |
3295 | /* break up if statements for readability */ | |
b6887d79 | 3296 | if ((flags & PROBE_TEST_FUNC) && entry->ops != ops) |
59df055f SR |
3297 | continue; |
3298 | ||
b6887d79 | 3299 | if ((flags & PROBE_TEST_DATA) && entry->data != data) |
59df055f SR |
3300 | continue; |
3301 | ||
3302 | /* do this last, since it is the most expensive */ | |
3303 | if (glob) { | |
3304 | kallsyms_lookup(entry->ip, NULL, NULL, | |
3305 | NULL, str); | |
3306 | if (!ftrace_match(str, glob, len, type)) | |
3307 | continue; | |
3308 | } | |
3309 | ||
e1df4cb6 SRRH |
3310 | rec_entry = ftrace_lookup_ip(hash, entry->ip); |
3311 | /* It is possible more than one entry had this ip */ | |
3312 | if (rec_entry) | |
3313 | free_hash_entry(hash, rec_entry); | |
3314 | ||
740466bc | 3315 | hlist_del_rcu(&entry->node); |
7818b388 | 3316 | list_add(&entry->free_list, &free_list); |
59df055f SR |
3317 | } |
3318 | } | |
3f2367ba | 3319 | mutex_lock(&ftrace_lock); |
b6887d79 | 3320 | __disable_ftrace_function_probe(); |
e1df4cb6 SRRH |
3321 | /* |
3322 | * Remove after the disable is called. Otherwise, if the last | |
3323 | * probe is removed, a null hash means *all enabled*. | |
3324 | */ | |
3325 | ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash); | |
7818b388 SRRH |
3326 | synchronize_sched(); |
3327 | list_for_each_entry_safe(entry, p, &free_list, free_list) { | |
3328 | list_del(&entry->free_list); | |
3329 | ftrace_free_entry(entry); | |
3330 | } | |
3f2367ba | 3331 | mutex_unlock(&ftrace_lock); |
7818b388 | 3332 | |
e1df4cb6 | 3333 | out_unlock: |
3f2367ba | 3334 | mutex_unlock(&trace_probe_ops.regex_lock); |
e1df4cb6 | 3335 | free_ftrace_hash(hash); |
59df055f SR |
3336 | } |
3337 | ||
3338 | void | |
b6887d79 | 3339 | unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3340 | void *data) |
3341 | { | |
b6887d79 SR |
3342 | __unregister_ftrace_function_probe(glob, ops, data, |
3343 | PROBE_TEST_FUNC | PROBE_TEST_DATA); | |
59df055f SR |
3344 | } |
3345 | ||
3346 | void | |
b6887d79 | 3347 | unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops) |
59df055f | 3348 | { |
b6887d79 | 3349 | __unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC); |
59df055f SR |
3350 | } |
3351 | ||
b6887d79 | 3352 | void unregister_ftrace_function_probe_all(char *glob) |
59df055f | 3353 | { |
b6887d79 | 3354 | __unregister_ftrace_function_probe(glob, NULL, NULL, 0); |
59df055f SR |
3355 | } |
3356 | ||
f6180773 SR |
3357 | static LIST_HEAD(ftrace_commands); |
3358 | static DEFINE_MUTEX(ftrace_cmd_mutex); | |
3359 | ||
3360 | int register_ftrace_command(struct ftrace_func_command *cmd) | |
3361 | { | |
3362 | struct ftrace_func_command *p; | |
3363 | int ret = 0; | |
3364 | ||
3365 | mutex_lock(&ftrace_cmd_mutex); | |
3366 | list_for_each_entry(p, &ftrace_commands, list) { | |
3367 | if (strcmp(cmd->name, p->name) == 0) { | |
3368 | ret = -EBUSY; | |
3369 | goto out_unlock; | |
3370 | } | |
3371 | } | |
3372 | list_add(&cmd->list, &ftrace_commands); | |
3373 | out_unlock: | |
3374 | mutex_unlock(&ftrace_cmd_mutex); | |
3375 | ||
3376 | return ret; | |
3377 | } | |
3378 | ||
3379 | int unregister_ftrace_command(struct ftrace_func_command *cmd) | |
3380 | { | |
3381 | struct ftrace_func_command *p, *n; | |
3382 | int ret = -ENODEV; | |
3383 | ||
3384 | mutex_lock(&ftrace_cmd_mutex); | |
3385 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { | |
3386 | if (strcmp(cmd->name, p->name) == 0) { | |
3387 | ret = 0; | |
3388 | list_del_init(&p->list); | |
3389 | goto out_unlock; | |
3390 | } | |
3391 | } | |
3392 | out_unlock: | |
3393 | mutex_unlock(&ftrace_cmd_mutex); | |
3394 | ||
3395 | return ret; | |
3396 | } | |
3397 | ||
33dc9b12 SR |
3398 | static int ftrace_process_regex(struct ftrace_hash *hash, |
3399 | char *buff, int len, int enable) | |
64e7c440 | 3400 | { |
f6180773 | 3401 | char *func, *command, *next = buff; |
6a24a244 | 3402 | struct ftrace_func_command *p; |
0aff1c0c | 3403 | int ret = -EINVAL; |
64e7c440 SR |
3404 | |
3405 | func = strsep(&next, ":"); | |
3406 | ||
3407 | if (!next) { | |
1cf41dd7 | 3408 | ret = ftrace_match_records(hash, func, len); |
b448c4e3 SR |
3409 | if (!ret) |
3410 | ret = -EINVAL; | |
3411 | if (ret < 0) | |
3412 | return ret; | |
3413 | return 0; | |
64e7c440 SR |
3414 | } |
3415 | ||
f6180773 | 3416 | /* command found */ |
64e7c440 SR |
3417 | |
3418 | command = strsep(&next, ":"); | |
3419 | ||
f6180773 SR |
3420 | mutex_lock(&ftrace_cmd_mutex); |
3421 | list_for_each_entry(p, &ftrace_commands, list) { | |
3422 | if (strcmp(p->name, command) == 0) { | |
43dd61c9 | 3423 | ret = p->func(hash, func, command, next, enable); |
f6180773 SR |
3424 | goto out_unlock; |
3425 | } | |
64e7c440 | 3426 | } |
f6180773 SR |
3427 | out_unlock: |
3428 | mutex_unlock(&ftrace_cmd_mutex); | |
64e7c440 | 3429 | |
f6180773 | 3430 | return ret; |
64e7c440 SR |
3431 | } |
3432 | ||
e309b41d | 3433 | static ssize_t |
41c52c0d SR |
3434 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
3435 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
3436 | { |
3437 | struct ftrace_iterator *iter; | |
689fd8b6 | 3438 | struct trace_parser *parser; |
3439 | ssize_t ret, read; | |
5072c59f | 3440 | |
4ba7978e | 3441 | if (!cnt) |
5072c59f SR |
3442 | return 0; |
3443 | ||
5072c59f SR |
3444 | if (file->f_mode & FMODE_READ) { |
3445 | struct seq_file *m = file->private_data; | |
3446 | iter = m->private; | |
3447 | } else | |
3448 | iter = file->private_data; | |
3449 | ||
f04f24fb | 3450 | if (unlikely(ftrace_disabled)) |
3f2367ba MH |
3451 | return -ENODEV; |
3452 | ||
3453 | /* iter->hash is a local copy, so we don't need regex_lock */ | |
f04f24fb | 3454 | |
689fd8b6 | 3455 | parser = &iter->parser; |
3456 | read = trace_get_user(parser, ubuf, cnt, ppos); | |
5072c59f | 3457 | |
4ba7978e | 3458 | if (read >= 0 && trace_parser_loaded(parser) && |
689fd8b6 | 3459 | !trace_parser_cont(parser)) { |
33dc9b12 | 3460 | ret = ftrace_process_regex(iter->hash, parser->buffer, |
689fd8b6 | 3461 | parser->idx, enable); |
313254a9 | 3462 | trace_parser_clear(parser); |
7c088b51 | 3463 | if (ret < 0) |
3f2367ba | 3464 | goto out; |
eda1e328 | 3465 | } |
5072c59f | 3466 | |
5072c59f | 3467 | ret = read; |
3f2367ba | 3468 | out: |
5072c59f SR |
3469 | return ret; |
3470 | } | |
3471 | ||
fc13cb0c | 3472 | ssize_t |
41c52c0d SR |
3473 | ftrace_filter_write(struct file *file, const char __user *ubuf, |
3474 | size_t cnt, loff_t *ppos) | |
3475 | { | |
3476 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
3477 | } | |
3478 | ||
fc13cb0c | 3479 | ssize_t |
41c52c0d SR |
3480 | ftrace_notrace_write(struct file *file, const char __user *ubuf, |
3481 | size_t cnt, loff_t *ppos) | |
3482 | { | |
3483 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
3484 | } | |
3485 | ||
33dc9b12 | 3486 | static int |
647664ea MH |
3487 | ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) |
3488 | { | |
3489 | struct ftrace_func_entry *entry; | |
3490 | ||
3491 | if (!ftrace_location(ip)) | |
3492 | return -EINVAL; | |
3493 | ||
3494 | if (remove) { | |
3495 | entry = ftrace_lookup_ip(hash, ip); | |
3496 | if (!entry) | |
3497 | return -ENOENT; | |
3498 | free_hash_entry(hash, entry); | |
3499 | return 0; | |
3500 | } | |
3501 | ||
3502 | return add_hash_entry(hash, ip); | |
3503 | } | |
3504 | ||
3505 | static int | |
3506 | ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, | |
3507 | unsigned long ip, int remove, int reset, int enable) | |
41c52c0d | 3508 | { |
33dc9b12 | 3509 | struct ftrace_hash **orig_hash; |
f45948e8 | 3510 | struct ftrace_hash *hash; |
33dc9b12 | 3511 | int ret; |
f45948e8 | 3512 | |
936e074b SR |
3513 | /* All global ops uses the global ops filters */ |
3514 | if (ops->flags & FTRACE_OPS_FL_GLOBAL) | |
3515 | ops = &global_ops; | |
3516 | ||
41c52c0d | 3517 | if (unlikely(ftrace_disabled)) |
33dc9b12 | 3518 | return -ENODEV; |
41c52c0d | 3519 | |
3f2367ba MH |
3520 | mutex_lock(&ops->regex_lock); |
3521 | ||
f45948e8 | 3522 | if (enable) |
33dc9b12 | 3523 | orig_hash = &ops->filter_hash; |
f45948e8 | 3524 | else |
33dc9b12 SR |
3525 | orig_hash = &ops->notrace_hash; |
3526 | ||
3527 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
3f2367ba MH |
3528 | if (!hash) { |
3529 | ret = -ENOMEM; | |
3530 | goto out_regex_unlock; | |
3531 | } | |
f45948e8 | 3532 | |
41c52c0d | 3533 | if (reset) |
1cf41dd7 | 3534 | ftrace_filter_reset(hash); |
ac483c44 JO |
3535 | if (buf && !ftrace_match_records(hash, buf, len)) { |
3536 | ret = -EINVAL; | |
3537 | goto out_regex_unlock; | |
3538 | } | |
647664ea MH |
3539 | if (ip) { |
3540 | ret = ftrace_match_addr(hash, ip, remove); | |
3541 | if (ret < 0) | |
3542 | goto out_regex_unlock; | |
3543 | } | |
33dc9b12 SR |
3544 | |
3545 | mutex_lock(&ftrace_lock); | |
41fb61c2 | 3546 | ret = ftrace_hash_move(ops, enable, orig_hash, hash); |
072126f4 SR |
3547 | if (!ret && ops->flags & FTRACE_OPS_FL_ENABLED |
3548 | && ftrace_enabled) | |
30fb6aa7 | 3549 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); |
072126f4 | 3550 | |
33dc9b12 SR |
3551 | mutex_unlock(&ftrace_lock); |
3552 | ||
ac483c44 | 3553 | out_regex_unlock: |
f04f24fb | 3554 | mutex_unlock(&ops->regex_lock); |
33dc9b12 SR |
3555 | |
3556 | free_ftrace_hash(hash); | |
3557 | return ret; | |
41c52c0d SR |
3558 | } |
3559 | ||
647664ea MH |
3560 | static int |
3561 | ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove, | |
3562 | int reset, int enable) | |
3563 | { | |
3564 | return ftrace_set_hash(ops, 0, 0, ip, remove, reset, enable); | |
3565 | } | |
3566 | ||
3567 | /** | |
3568 | * ftrace_set_filter_ip - set a function to filter on in ftrace by address | |
3569 | * @ops - the ops to set the filter with | |
3570 | * @ip - the address to add to or remove from the filter. | |
3571 | * @remove - non zero to remove the ip from the filter | |
3572 | * @reset - non zero to reset all filters before applying this filter. | |
3573 | * | |
3574 | * Filters denote which functions should be enabled when tracing is enabled | |
3575 | * If @ip is NULL, it failes to update filter. | |
3576 | */ | |
3577 | int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, | |
3578 | int remove, int reset) | |
3579 | { | |
f04f24fb | 3580 | ftrace_ops_init(ops); |
647664ea MH |
3581 | return ftrace_set_addr(ops, ip, remove, reset, 1); |
3582 | } | |
3583 | EXPORT_SYMBOL_GPL(ftrace_set_filter_ip); | |
3584 | ||
3585 | static int | |
3586 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, | |
3587 | int reset, int enable) | |
3588 | { | |
3589 | return ftrace_set_hash(ops, buf, len, 0, 0, reset, enable); | |
3590 | } | |
3591 | ||
77a2b37d SR |
3592 | /** |
3593 | * ftrace_set_filter - set a function to filter on in ftrace | |
936e074b SR |
3594 | * @ops - the ops to set the filter with |
3595 | * @buf - the string that holds the function filter text. | |
3596 | * @len - the length of the string. | |
3597 | * @reset - non zero to reset all filters before applying this filter. | |
3598 | * | |
3599 | * Filters denote which functions should be enabled when tracing is enabled. | |
3600 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
3601 | */ | |
ac483c44 | 3602 | int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
3603 | int len, int reset) |
3604 | { | |
f04f24fb | 3605 | ftrace_ops_init(ops); |
ac483c44 | 3606 | return ftrace_set_regex(ops, buf, len, reset, 1); |
936e074b SR |
3607 | } |
3608 | EXPORT_SYMBOL_GPL(ftrace_set_filter); | |
3609 | ||
3610 | /** | |
3611 | * ftrace_set_notrace - set a function to not trace in ftrace | |
3612 | * @ops - the ops to set the notrace filter with | |
3613 | * @buf - the string that holds the function notrace text. | |
3614 | * @len - the length of the string. | |
3615 | * @reset - non zero to reset all filters before applying this filter. | |
3616 | * | |
3617 | * Notrace Filters denote which functions should not be enabled when tracing | |
3618 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
3619 | * for tracing. | |
3620 | */ | |
ac483c44 | 3621 | int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
3622 | int len, int reset) |
3623 | { | |
f04f24fb | 3624 | ftrace_ops_init(ops); |
ac483c44 | 3625 | return ftrace_set_regex(ops, buf, len, reset, 0); |
936e074b SR |
3626 | } |
3627 | EXPORT_SYMBOL_GPL(ftrace_set_notrace); | |
3628 | /** | |
3629 | * ftrace_set_filter - set a function to filter on in ftrace | |
3630 | * @ops - the ops to set the filter with | |
77a2b37d SR |
3631 | * @buf - the string that holds the function filter text. |
3632 | * @len - the length of the string. | |
3633 | * @reset - non zero to reset all filters before applying this filter. | |
3634 | * | |
3635 | * Filters denote which functions should be enabled when tracing is enabled. | |
3636 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
3637 | */ | |
936e074b | 3638 | void ftrace_set_global_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 3639 | { |
f45948e8 | 3640 | ftrace_set_regex(&global_ops, buf, len, reset, 1); |
41c52c0d | 3641 | } |
936e074b | 3642 | EXPORT_SYMBOL_GPL(ftrace_set_global_filter); |
4eebcc81 | 3643 | |
41c52c0d SR |
3644 | /** |
3645 | * ftrace_set_notrace - set a function to not trace in ftrace | |
936e074b | 3646 | * @ops - the ops to set the notrace filter with |
41c52c0d SR |
3647 | * @buf - the string that holds the function notrace text. |
3648 | * @len - the length of the string. | |
3649 | * @reset - non zero to reset all filters before applying this filter. | |
3650 | * | |
3651 | * Notrace Filters denote which functions should not be enabled when tracing | |
3652 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
3653 | * for tracing. | |
3654 | */ | |
936e074b | 3655 | void ftrace_set_global_notrace(unsigned char *buf, int len, int reset) |
41c52c0d | 3656 | { |
f45948e8 | 3657 | ftrace_set_regex(&global_ops, buf, len, reset, 0); |
77a2b37d | 3658 | } |
936e074b | 3659 | EXPORT_SYMBOL_GPL(ftrace_set_global_notrace); |
77a2b37d | 3660 | |
2af15d6a SR |
3661 | /* |
3662 | * command line interface to allow users to set filters on boot up. | |
3663 | */ | |
3664 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE | |
3665 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; | |
3666 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; | |
3667 | ||
3668 | static int __init set_ftrace_notrace(char *str) | |
3669 | { | |
75761cc1 | 3670 | strlcpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
3671 | return 1; |
3672 | } | |
3673 | __setup("ftrace_notrace=", set_ftrace_notrace); | |
3674 | ||
3675 | static int __init set_ftrace_filter(char *str) | |
3676 | { | |
75761cc1 | 3677 | strlcpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
3678 | return 1; |
3679 | } | |
3680 | __setup("ftrace_filter=", set_ftrace_filter); | |
3681 | ||
369bc18f | 3682 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
f6060f46 | 3683 | static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; |
801c29fd SR |
3684 | static int ftrace_set_func(unsigned long *array, int *idx, char *buffer); |
3685 | ||
369bc18f SA |
3686 | static int __init set_graph_function(char *str) |
3687 | { | |
06f43d66 | 3688 | strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); |
369bc18f SA |
3689 | return 1; |
3690 | } | |
3691 | __setup("ftrace_graph_filter=", set_graph_function); | |
3692 | ||
3693 | static void __init set_ftrace_early_graph(char *buf) | |
3694 | { | |
3695 | int ret; | |
3696 | char *func; | |
3697 | ||
3698 | while (buf) { | |
3699 | func = strsep(&buf, ","); | |
3700 | /* we allow only one expression at a time */ | |
3701 | ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, | |
3702 | func); | |
3703 | if (ret) | |
3704 | printk(KERN_DEBUG "ftrace: function %s not " | |
3705 | "traceable\n", func); | |
3706 | } | |
3707 | } | |
3708 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
3709 | ||
2a85a37f SR |
3710 | void __init |
3711 | ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable) | |
2af15d6a SR |
3712 | { |
3713 | char *func; | |
3714 | ||
f04f24fb MH |
3715 | ftrace_ops_init(ops); |
3716 | ||
2af15d6a SR |
3717 | while (buf) { |
3718 | func = strsep(&buf, ","); | |
f45948e8 | 3719 | ftrace_set_regex(ops, func, strlen(func), 0, enable); |
2af15d6a SR |
3720 | } |
3721 | } | |
3722 | ||
3723 | static void __init set_ftrace_early_filters(void) | |
3724 | { | |
3725 | if (ftrace_filter_buf[0]) | |
2a85a37f | 3726 | ftrace_set_early_filter(&global_ops, ftrace_filter_buf, 1); |
2af15d6a | 3727 | if (ftrace_notrace_buf[0]) |
2a85a37f | 3728 | ftrace_set_early_filter(&global_ops, ftrace_notrace_buf, 0); |
369bc18f SA |
3729 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
3730 | if (ftrace_graph_buf[0]) | |
3731 | set_ftrace_early_graph(ftrace_graph_buf); | |
3732 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
2af15d6a SR |
3733 | } |
3734 | ||
fc13cb0c | 3735 | int ftrace_regex_release(struct inode *inode, struct file *file) |
5072c59f SR |
3736 | { |
3737 | struct seq_file *m = (struct seq_file *)file->private_data; | |
3738 | struct ftrace_iterator *iter; | |
33dc9b12 | 3739 | struct ftrace_hash **orig_hash; |
689fd8b6 | 3740 | struct trace_parser *parser; |
ed926f9b | 3741 | int filter_hash; |
33dc9b12 | 3742 | int ret; |
5072c59f | 3743 | |
5072c59f SR |
3744 | if (file->f_mode & FMODE_READ) { |
3745 | iter = m->private; | |
5072c59f SR |
3746 | seq_release(inode, file); |
3747 | } else | |
3748 | iter = file->private_data; | |
3749 | ||
689fd8b6 | 3750 | parser = &iter->parser; |
3751 | if (trace_parser_loaded(parser)) { | |
3752 | parser->buffer[parser->idx] = 0; | |
1cf41dd7 | 3753 | ftrace_match_records(iter->hash, parser->buffer, parser->idx); |
5072c59f SR |
3754 | } |
3755 | ||
689fd8b6 | 3756 | trace_parser_put(parser); |
689fd8b6 | 3757 | |
3f2367ba MH |
3758 | mutex_lock(&iter->ops->regex_lock); |
3759 | ||
058e297d | 3760 | if (file->f_mode & FMODE_WRITE) { |
ed926f9b SR |
3761 | filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); |
3762 | ||
3763 | if (filter_hash) | |
33dc9b12 | 3764 | orig_hash = &iter->ops->filter_hash; |
ed926f9b SR |
3765 | else |
3766 | orig_hash = &iter->ops->notrace_hash; | |
33dc9b12 | 3767 | |
058e297d | 3768 | mutex_lock(&ftrace_lock); |
41fb61c2 SR |
3769 | ret = ftrace_hash_move(iter->ops, filter_hash, |
3770 | orig_hash, iter->hash); | |
3771 | if (!ret && (iter->ops->flags & FTRACE_OPS_FL_ENABLED) | |
3772 | && ftrace_enabled) | |
30fb6aa7 | 3773 | ftrace_run_update_code(FTRACE_UPDATE_CALLS); |
41fb61c2 | 3774 | |
058e297d SR |
3775 | mutex_unlock(&ftrace_lock); |
3776 | } | |
3f2367ba MH |
3777 | |
3778 | mutex_unlock(&iter->ops->regex_lock); | |
33dc9b12 SR |
3779 | free_ftrace_hash(iter->hash); |
3780 | kfree(iter); | |
058e297d | 3781 | |
5072c59f SR |
3782 | return 0; |
3783 | } | |
3784 | ||
5e2336a0 | 3785 | static const struct file_operations ftrace_avail_fops = { |
5072c59f SR |
3786 | .open = ftrace_avail_open, |
3787 | .read = seq_read, | |
3788 | .llseek = seq_lseek, | |
3be04b47 | 3789 | .release = seq_release_private, |
5072c59f SR |
3790 | }; |
3791 | ||
647bcd03 SR |
3792 | static const struct file_operations ftrace_enabled_fops = { |
3793 | .open = ftrace_enabled_open, | |
3794 | .read = seq_read, | |
3795 | .llseek = seq_lseek, | |
3796 | .release = seq_release_private, | |
3797 | }; | |
3798 | ||
5e2336a0 | 3799 | static const struct file_operations ftrace_filter_fops = { |
5072c59f | 3800 | .open = ftrace_filter_open, |
850a80cf | 3801 | .read = seq_read, |
5072c59f | 3802 | .write = ftrace_filter_write, |
6a76f8c0 | 3803 | .llseek = ftrace_filter_lseek, |
1cf41dd7 | 3804 | .release = ftrace_regex_release, |
5072c59f SR |
3805 | }; |
3806 | ||
5e2336a0 | 3807 | static const struct file_operations ftrace_notrace_fops = { |
41c52c0d | 3808 | .open = ftrace_notrace_open, |
850a80cf | 3809 | .read = seq_read, |
41c52c0d | 3810 | .write = ftrace_notrace_write, |
6a76f8c0 | 3811 | .llseek = ftrace_filter_lseek, |
1cf41dd7 | 3812 | .release = ftrace_regex_release, |
41c52c0d SR |
3813 | }; |
3814 | ||
ea4e2bc4 SR |
3815 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
3816 | ||
3817 | static DEFINE_MUTEX(graph_lock); | |
3818 | ||
3819 | int ftrace_graph_count; | |
c7c6b1fe | 3820 | int ftrace_graph_filter_enabled; |
ea4e2bc4 SR |
3821 | unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; |
3822 | ||
3823 | static void * | |
85951842 | 3824 | __g_next(struct seq_file *m, loff_t *pos) |
ea4e2bc4 | 3825 | { |
85951842 | 3826 | if (*pos >= ftrace_graph_count) |
ea4e2bc4 | 3827 | return NULL; |
a4ec5e0c | 3828 | return &ftrace_graph_funcs[*pos]; |
85951842 | 3829 | } |
ea4e2bc4 | 3830 | |
85951842 LZ |
3831 | static void * |
3832 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
3833 | { | |
3834 | (*pos)++; | |
3835 | return __g_next(m, pos); | |
ea4e2bc4 SR |
3836 | } |
3837 | ||
3838 | static void *g_start(struct seq_file *m, loff_t *pos) | |
3839 | { | |
ea4e2bc4 SR |
3840 | mutex_lock(&graph_lock); |
3841 | ||
f9349a8f | 3842 | /* Nothing, tell g_show to print all functions are enabled */ |
c7c6b1fe | 3843 | if (!ftrace_graph_filter_enabled && !*pos) |
f9349a8f FW |
3844 | return (void *)1; |
3845 | ||
85951842 | 3846 | return __g_next(m, pos); |
ea4e2bc4 SR |
3847 | } |
3848 | ||
3849 | static void g_stop(struct seq_file *m, void *p) | |
3850 | { | |
3851 | mutex_unlock(&graph_lock); | |
3852 | } | |
3853 | ||
3854 | static int g_show(struct seq_file *m, void *v) | |
3855 | { | |
3856 | unsigned long *ptr = v; | |
ea4e2bc4 SR |
3857 | |
3858 | if (!ptr) | |
3859 | return 0; | |
3860 | ||
f9349a8f FW |
3861 | if (ptr == (unsigned long *)1) { |
3862 | seq_printf(m, "#### all functions enabled ####\n"); | |
3863 | return 0; | |
3864 | } | |
3865 | ||
b375a11a | 3866 | seq_printf(m, "%ps\n", (void *)*ptr); |
ea4e2bc4 SR |
3867 | |
3868 | return 0; | |
3869 | } | |
3870 | ||
88e9d34c | 3871 | static const struct seq_operations ftrace_graph_seq_ops = { |
ea4e2bc4 SR |
3872 | .start = g_start, |
3873 | .next = g_next, | |
3874 | .stop = g_stop, | |
3875 | .show = g_show, | |
3876 | }; | |
3877 | ||
3878 | static int | |
3879 | ftrace_graph_open(struct inode *inode, struct file *file) | |
3880 | { | |
3881 | int ret = 0; | |
3882 | ||
3883 | if (unlikely(ftrace_disabled)) | |
3884 | return -ENODEV; | |
3885 | ||
3886 | mutex_lock(&graph_lock); | |
3887 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 3888 | (file->f_flags & O_TRUNC)) { |
c7c6b1fe | 3889 | ftrace_graph_filter_enabled = 0; |
ea4e2bc4 SR |
3890 | ftrace_graph_count = 0; |
3891 | memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); | |
3892 | } | |
a4ec5e0c | 3893 | mutex_unlock(&graph_lock); |
ea4e2bc4 | 3894 | |
a4ec5e0c | 3895 | if (file->f_mode & FMODE_READ) |
ea4e2bc4 | 3896 | ret = seq_open(file, &ftrace_graph_seq_ops); |
ea4e2bc4 SR |
3897 | |
3898 | return ret; | |
3899 | } | |
3900 | ||
87827111 LZ |
3901 | static int |
3902 | ftrace_graph_release(struct inode *inode, struct file *file) | |
3903 | { | |
3904 | if (file->f_mode & FMODE_READ) | |
3905 | seq_release(inode, file); | |
3906 | return 0; | |
3907 | } | |
3908 | ||
ea4e2bc4 | 3909 | static int |
f9349a8f | 3910 | ftrace_set_func(unsigned long *array, int *idx, char *buffer) |
ea4e2bc4 | 3911 | { |
ea4e2bc4 SR |
3912 | struct dyn_ftrace *rec; |
3913 | struct ftrace_page *pg; | |
f9349a8f | 3914 | int search_len; |
c7c6b1fe | 3915 | int fail = 1; |
f9349a8f FW |
3916 | int type, not; |
3917 | char *search; | |
3918 | bool exists; | |
3919 | int i; | |
ea4e2bc4 | 3920 | |
f9349a8f | 3921 | /* decode regex */ |
3f6fe06d | 3922 | type = filter_parse_regex(buffer, strlen(buffer), &search, ¬); |
c7c6b1fe LZ |
3923 | if (!not && *idx >= FTRACE_GRAPH_MAX_FUNCS) |
3924 | return -EBUSY; | |
f9349a8f FW |
3925 | |
3926 | search_len = strlen(search); | |
3927 | ||
52baf119 | 3928 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
3929 | |
3930 | if (unlikely(ftrace_disabled)) { | |
3931 | mutex_unlock(&ftrace_lock); | |
3932 | return -ENODEV; | |
3933 | } | |
3934 | ||
265c831c SR |
3935 | do_for_each_ftrace_rec(pg, rec) { |
3936 | ||
b9df92d2 | 3937 | if (ftrace_match_record(rec, NULL, search, search_len, type)) { |
c7c6b1fe | 3938 | /* if it is in the array */ |
f9349a8f | 3939 | exists = false; |
c7c6b1fe | 3940 | for (i = 0; i < *idx; i++) { |
f9349a8f FW |
3941 | if (array[i] == rec->ip) { |
3942 | exists = true; | |
265c831c SR |
3943 | break; |
3944 | } | |
c7c6b1fe LZ |
3945 | } |
3946 | ||
3947 | if (!not) { | |
3948 | fail = 0; | |
3949 | if (!exists) { | |
3950 | array[(*idx)++] = rec->ip; | |
3951 | if (*idx >= FTRACE_GRAPH_MAX_FUNCS) | |
3952 | goto out; | |
3953 | } | |
3954 | } else { | |
3955 | if (exists) { | |
3956 | array[i] = array[--(*idx)]; | |
3957 | array[*idx] = 0; | |
3958 | fail = 0; | |
3959 | } | |
3960 | } | |
ea4e2bc4 | 3961 | } |
265c831c | 3962 | } while_for_each_ftrace_rec(); |
c7c6b1fe | 3963 | out: |
52baf119 | 3964 | mutex_unlock(&ftrace_lock); |
ea4e2bc4 | 3965 | |
c7c6b1fe LZ |
3966 | if (fail) |
3967 | return -EINVAL; | |
3968 | ||
9f50afcc NK |
3969 | ftrace_graph_filter_enabled = !!(*idx); |
3970 | ||
c7c6b1fe | 3971 | return 0; |
ea4e2bc4 SR |
3972 | } |
3973 | ||
3974 | static ssize_t | |
3975 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
3976 | size_t cnt, loff_t *ppos) | |
3977 | { | |
689fd8b6 | 3978 | struct trace_parser parser; |
4ba7978e | 3979 | ssize_t read, ret; |
ea4e2bc4 | 3980 | |
c7c6b1fe | 3981 | if (!cnt) |
ea4e2bc4 SR |
3982 | return 0; |
3983 | ||
3984 | mutex_lock(&graph_lock); | |
3985 | ||
689fd8b6 | 3986 | if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) { |
3987 | ret = -ENOMEM; | |
1eb90f13 | 3988 | goto out_unlock; |
ea4e2bc4 SR |
3989 | } |
3990 | ||
689fd8b6 | 3991 | read = trace_get_user(&parser, ubuf, cnt, ppos); |
ea4e2bc4 | 3992 | |
4ba7978e | 3993 | if (read >= 0 && trace_parser_loaded((&parser))) { |
689fd8b6 | 3994 | parser.buffer[parser.idx] = 0; |
3995 | ||
3996 | /* we allow only one expression at a time */ | |
a4ec5e0c | 3997 | ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, |
689fd8b6 | 3998 | parser.buffer); |
ea4e2bc4 | 3999 | if (ret) |
1eb90f13 | 4000 | goto out_free; |
ea4e2bc4 | 4001 | } |
ea4e2bc4 SR |
4002 | |
4003 | ret = read; | |
1eb90f13 LZ |
4004 | |
4005 | out_free: | |
689fd8b6 | 4006 | trace_parser_put(&parser); |
1eb90f13 | 4007 | out_unlock: |
ea4e2bc4 SR |
4008 | mutex_unlock(&graph_lock); |
4009 | ||
4010 | return ret; | |
4011 | } | |
4012 | ||
4013 | static const struct file_operations ftrace_graph_fops = { | |
87827111 LZ |
4014 | .open = ftrace_graph_open, |
4015 | .read = seq_read, | |
4016 | .write = ftrace_graph_write, | |
6a76f8c0 | 4017 | .llseek = ftrace_filter_lseek, |
87827111 | 4018 | .release = ftrace_graph_release, |
ea4e2bc4 SR |
4019 | }; |
4020 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
4021 | ||
df4fc315 | 4022 | static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) |
5072c59f | 4023 | { |
5072c59f | 4024 | |
5452af66 FW |
4025 | trace_create_file("available_filter_functions", 0444, |
4026 | d_tracer, NULL, &ftrace_avail_fops); | |
5072c59f | 4027 | |
647bcd03 SR |
4028 | trace_create_file("enabled_functions", 0444, |
4029 | d_tracer, NULL, &ftrace_enabled_fops); | |
4030 | ||
5452af66 FW |
4031 | trace_create_file("set_ftrace_filter", 0644, d_tracer, |
4032 | NULL, &ftrace_filter_fops); | |
41c52c0d | 4033 | |
5452af66 | 4034 | trace_create_file("set_ftrace_notrace", 0644, d_tracer, |
41c52c0d | 4035 | NULL, &ftrace_notrace_fops); |
ad90c0e3 | 4036 | |
ea4e2bc4 | 4037 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5452af66 | 4038 | trace_create_file("set_graph_function", 0444, d_tracer, |
ea4e2bc4 SR |
4039 | NULL, |
4040 | &ftrace_graph_fops); | |
ea4e2bc4 SR |
4041 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
4042 | ||
5072c59f SR |
4043 | return 0; |
4044 | } | |
4045 | ||
9fd49328 | 4046 | static int ftrace_cmp_ips(const void *a, const void *b) |
68950619 | 4047 | { |
9fd49328 SR |
4048 | const unsigned long *ipa = a; |
4049 | const unsigned long *ipb = b; | |
68950619 | 4050 | |
9fd49328 SR |
4051 | if (*ipa > *ipb) |
4052 | return 1; | |
4053 | if (*ipa < *ipb) | |
4054 | return -1; | |
4055 | return 0; | |
4056 | } | |
4057 | ||
4058 | static void ftrace_swap_ips(void *a, void *b, int size) | |
4059 | { | |
4060 | unsigned long *ipa = a; | |
4061 | unsigned long *ipb = b; | |
4062 | unsigned long t; | |
4063 | ||
4064 | t = *ipa; | |
4065 | *ipa = *ipb; | |
4066 | *ipb = t; | |
68950619 SR |
4067 | } |
4068 | ||
5cb084bb | 4069 | static int ftrace_process_locs(struct module *mod, |
31e88909 | 4070 | unsigned long *start, |
68bf21aa SR |
4071 | unsigned long *end) |
4072 | { | |
706c81f8 | 4073 | struct ftrace_page *start_pg; |
a7900875 | 4074 | struct ftrace_page *pg; |
706c81f8 | 4075 | struct dyn_ftrace *rec; |
a7900875 | 4076 | unsigned long count; |
68bf21aa SR |
4077 | unsigned long *p; |
4078 | unsigned long addr; | |
4376cac6 | 4079 | unsigned long flags = 0; /* Shut up gcc */ |
a7900875 SR |
4080 | int ret = -ENOMEM; |
4081 | ||
4082 | count = end - start; | |
4083 | ||
4084 | if (!count) | |
4085 | return 0; | |
4086 | ||
9fd49328 SR |
4087 | sort(start, count, sizeof(*start), |
4088 | ftrace_cmp_ips, ftrace_swap_ips); | |
4089 | ||
706c81f8 SR |
4090 | start_pg = ftrace_allocate_pages(count); |
4091 | if (!start_pg) | |
a7900875 | 4092 | return -ENOMEM; |
68bf21aa | 4093 | |
e6ea44e9 | 4094 | mutex_lock(&ftrace_lock); |
a7900875 | 4095 | |
32082309 SR |
4096 | /* |
4097 | * Core and each module needs their own pages, as | |
4098 | * modules will free them when they are removed. | |
4099 | * Force a new page to be allocated for modules. | |
4100 | */ | |
a7900875 SR |
4101 | if (!mod) { |
4102 | WARN_ON(ftrace_pages || ftrace_pages_start); | |
4103 | /* First initialization */ | |
706c81f8 | 4104 | ftrace_pages = ftrace_pages_start = start_pg; |
a7900875 | 4105 | } else { |
32082309 | 4106 | if (!ftrace_pages) |
a7900875 | 4107 | goto out; |
32082309 | 4108 | |
a7900875 SR |
4109 | if (WARN_ON(ftrace_pages->next)) { |
4110 | /* Hmm, we have free pages? */ | |
4111 | while (ftrace_pages->next) | |
4112 | ftrace_pages = ftrace_pages->next; | |
32082309 | 4113 | } |
a7900875 | 4114 | |
706c81f8 | 4115 | ftrace_pages->next = start_pg; |
32082309 SR |
4116 | } |
4117 | ||
68bf21aa | 4118 | p = start; |
706c81f8 | 4119 | pg = start_pg; |
68bf21aa SR |
4120 | while (p < end) { |
4121 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
4122 | /* |
4123 | * Some architecture linkers will pad between | |
4124 | * the different mcount_loc sections of different | |
4125 | * object files to satisfy alignments. | |
4126 | * Skip any NULL pointers. | |
4127 | */ | |
4128 | if (!addr) | |
4129 | continue; | |
706c81f8 SR |
4130 | |
4131 | if (pg->index == pg->size) { | |
4132 | /* We should have allocated enough */ | |
4133 | if (WARN_ON(!pg->next)) | |
4134 | break; | |
4135 | pg = pg->next; | |
4136 | } | |
4137 | ||
4138 | rec = &pg->records[pg->index++]; | |
4139 | rec->ip = addr; | |
68bf21aa SR |
4140 | } |
4141 | ||
706c81f8 SR |
4142 | /* We should have used all pages */ |
4143 | WARN_ON(pg->next); | |
4144 | ||
4145 | /* Assign the last page to ftrace_pages */ | |
4146 | ftrace_pages = pg; | |
4147 | ||
85ae32ae | 4148 | /* These new locations need to be initialized */ |
706c81f8 | 4149 | ftrace_new_pgs = start_pg; |
85ae32ae | 4150 | |
a4f18ed1 | 4151 | /* |
4376cac6 SR |
4152 | * We only need to disable interrupts on start up |
4153 | * because we are modifying code that an interrupt | |
4154 | * may execute, and the modification is not atomic. | |
4155 | * But for modules, nothing runs the code we modify | |
4156 | * until we are finished with it, and there's no | |
4157 | * reason to cause large interrupt latencies while we do it. | |
a4f18ed1 | 4158 | */ |
4376cac6 SR |
4159 | if (!mod) |
4160 | local_irq_save(flags); | |
31e88909 | 4161 | ftrace_update_code(mod); |
4376cac6 SR |
4162 | if (!mod) |
4163 | local_irq_restore(flags); | |
a7900875 SR |
4164 | ret = 0; |
4165 | out: | |
e6ea44e9 | 4166 | mutex_unlock(&ftrace_lock); |
68bf21aa | 4167 | |
a7900875 | 4168 | return ret; |
68bf21aa SR |
4169 | } |
4170 | ||
93eb677d | 4171 | #ifdef CONFIG_MODULES |
32082309 SR |
4172 | |
4173 | #define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next) | |
4174 | ||
e7247a15 | 4175 | void ftrace_release_mod(struct module *mod) |
93eb677d SR |
4176 | { |
4177 | struct dyn_ftrace *rec; | |
32082309 | 4178 | struct ftrace_page **last_pg; |
93eb677d | 4179 | struct ftrace_page *pg; |
a7900875 | 4180 | int order; |
93eb677d | 4181 | |
45a4a237 SR |
4182 | mutex_lock(&ftrace_lock); |
4183 | ||
e7247a15 | 4184 | if (ftrace_disabled) |
45a4a237 | 4185 | goto out_unlock; |
93eb677d | 4186 | |
32082309 SR |
4187 | /* |
4188 | * Each module has its own ftrace_pages, remove | |
4189 | * them from the list. | |
4190 | */ | |
4191 | last_pg = &ftrace_pages_start; | |
4192 | for (pg = ftrace_pages_start; pg; pg = *last_pg) { | |
4193 | rec = &pg->records[0]; | |
e7247a15 | 4194 | if (within_module_core(rec->ip, mod)) { |
93eb677d | 4195 | /* |
32082309 SR |
4196 | * As core pages are first, the first |
4197 | * page should never be a module page. | |
93eb677d | 4198 | */ |
32082309 SR |
4199 | if (WARN_ON(pg == ftrace_pages_start)) |
4200 | goto out_unlock; | |
4201 | ||
4202 | /* Check if we are deleting the last page */ | |
4203 | if (pg == ftrace_pages) | |
4204 | ftrace_pages = next_to_ftrace_page(last_pg); | |
4205 | ||
4206 | *last_pg = pg->next; | |
a7900875 SR |
4207 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); |
4208 | free_pages((unsigned long)pg->records, order); | |
4209 | kfree(pg); | |
32082309 SR |
4210 | } else |
4211 | last_pg = &pg->next; | |
4212 | } | |
45a4a237 | 4213 | out_unlock: |
93eb677d SR |
4214 | mutex_unlock(&ftrace_lock); |
4215 | } | |
4216 | ||
4217 | static void ftrace_init_module(struct module *mod, | |
4218 | unsigned long *start, unsigned long *end) | |
90d595fe | 4219 | { |
00fd61ae | 4220 | if (ftrace_disabled || start == end) |
fed1939c | 4221 | return; |
5cb084bb | 4222 | ftrace_process_locs(mod, start, end); |
90d595fe SR |
4223 | } |
4224 | ||
7d54b5cd | 4225 | void ftrace_module_init(struct module *mod) |
93eb677d | 4226 | { |
7d54b5cd SRRH |
4227 | ftrace_init_module(mod, mod->ftrace_callsites, |
4228 | mod->ftrace_callsites + | |
4229 | mod->num_ftrace_callsites); | |
8c189ea6 SRRH |
4230 | } |
4231 | ||
4232 | static int ftrace_module_notify_exit(struct notifier_block *self, | |
4233 | unsigned long val, void *data) | |
4234 | { | |
4235 | struct module *mod = data; | |
4236 | ||
4237 | if (val == MODULE_STATE_GOING) | |
e7247a15 | 4238 | ftrace_release_mod(mod); |
93eb677d SR |
4239 | |
4240 | return 0; | |
4241 | } | |
4242 | #else | |
8c189ea6 SRRH |
4243 | static int ftrace_module_notify_exit(struct notifier_block *self, |
4244 | unsigned long val, void *data) | |
93eb677d SR |
4245 | { |
4246 | return 0; | |
4247 | } | |
4248 | #endif /* CONFIG_MODULES */ | |
4249 | ||
8c189ea6 SRRH |
4250 | struct notifier_block ftrace_module_exit_nb = { |
4251 | .notifier_call = ftrace_module_notify_exit, | |
4252 | .priority = INT_MIN, /* Run after anything that can remove kprobes */ | |
4253 | }; | |
4254 | ||
68bf21aa SR |
4255 | extern unsigned long __start_mcount_loc[]; |
4256 | extern unsigned long __stop_mcount_loc[]; | |
4257 | ||
4258 | void __init ftrace_init(void) | |
4259 | { | |
4260 | unsigned long count, addr, flags; | |
4261 | int ret; | |
4262 | ||
4263 | /* Keep the ftrace pointer to the stub */ | |
4264 | addr = (unsigned long)ftrace_stub; | |
4265 | ||
4266 | local_irq_save(flags); | |
4267 | ftrace_dyn_arch_init(&addr); | |
4268 | local_irq_restore(flags); | |
4269 | ||
4270 | /* ftrace_dyn_arch_init places the return code in addr */ | |
4271 | if (addr) | |
4272 | goto failed; | |
4273 | ||
4274 | count = __stop_mcount_loc - __start_mcount_loc; | |
4275 | ||
4276 | ret = ftrace_dyn_table_alloc(count); | |
4277 | if (ret) | |
4278 | goto failed; | |
4279 | ||
4280 | last_ftrace_enabled = ftrace_enabled = 1; | |
4281 | ||
5cb084bb | 4282 | ret = ftrace_process_locs(NULL, |
31e88909 | 4283 | __start_mcount_loc, |
68bf21aa SR |
4284 | __stop_mcount_loc); |
4285 | ||
8c189ea6 | 4286 | ret = register_module_notifier(&ftrace_module_exit_nb); |
24ed0c4b | 4287 | if (ret) |
8c189ea6 | 4288 | pr_warning("Failed to register trace ftrace module exit notifier\n"); |
93eb677d | 4289 | |
2af15d6a SR |
4290 | set_ftrace_early_filters(); |
4291 | ||
68bf21aa SR |
4292 | return; |
4293 | failed: | |
4294 | ftrace_disabled = 1; | |
4295 | } | |
68bf21aa | 4296 | |
3d083395 | 4297 | #else |
0b6e4d56 | 4298 | |
2b499381 | 4299 | static struct ftrace_ops global_ops = { |
bd69c30b | 4300 | .func = ftrace_stub, |
f04f24fb MH |
4301 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, |
4302 | INIT_REGEX_LOCK(global_ops) | |
bd69c30b SR |
4303 | }; |
4304 | ||
0b6e4d56 FW |
4305 | static int __init ftrace_nodyn_init(void) |
4306 | { | |
4307 | ftrace_enabled = 1; | |
4308 | return 0; | |
4309 | } | |
6f415672 | 4310 | core_initcall(ftrace_nodyn_init); |
0b6e4d56 | 4311 | |
df4fc315 SR |
4312 | static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } |
4313 | static inline void ftrace_startup_enable(int command) { } | |
5a45cfe1 | 4314 | /* Keep as macros so we do not need to define the commands */ |
2940c25b SRRH |
4315 | # define ftrace_startup(ops, command) \ |
4316 | ({ \ | |
4317 | int ___ret = __register_ftrace_function(ops); \ | |
4318 | if (!___ret) \ | |
4319 | (ops)->flags |= FTRACE_OPS_FL_ENABLED; \ | |
4320 | ___ret; \ | |
3b6cfdb1 | 4321 | }) |
2940c25b SRRH |
4322 | # define ftrace_shutdown(ops, command) __unregister_ftrace_function(ops) |
4323 | ||
c7aafc54 IM |
4324 | # define ftrace_startup_sysctl() do { } while (0) |
4325 | # define ftrace_shutdown_sysctl() do { } while (0) | |
b848914c SR |
4326 | |
4327 | static inline int | |
29632b10 | 4328 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs) |
b848914c SR |
4329 | { |
4330 | return 1; | |
4331 | } | |
4332 | ||
3d083395 SR |
4333 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
4334 | ||
e248491a | 4335 | static void |
2f5f6ad9 | 4336 | ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 4337 | struct ftrace_ops *op, struct pt_regs *regs) |
e248491a | 4338 | { |
e248491a JO |
4339 | if (unlikely(trace_recursion_test(TRACE_CONTROL_BIT))) |
4340 | return; | |
4341 | ||
4342 | /* | |
4343 | * Some of the ops may be dynamically allocated, | |
4344 | * they must be freed after a synchronize_sched(). | |
4345 | */ | |
4346 | preempt_disable_notrace(); | |
4347 | trace_recursion_set(TRACE_CONTROL_BIT); | |
0a016409 | 4348 | do_for_each_ftrace_op(op, ftrace_control_list) { |
395b97a3 SRRH |
4349 | if (!(op->flags & FTRACE_OPS_FL_STUB) && |
4350 | !ftrace_function_local_disabled(op) && | |
29632b10 | 4351 | ftrace_ops_test(op, ip, regs)) |
a1e2e31d | 4352 | op->func(ip, parent_ip, op, regs); |
0a016409 | 4353 | } while_for_each_ftrace_op(op); |
e248491a JO |
4354 | trace_recursion_clear(TRACE_CONTROL_BIT); |
4355 | preempt_enable_notrace(); | |
4356 | } | |
4357 | ||
4358 | static struct ftrace_ops control_ops = { | |
f04f24fb MH |
4359 | .func = ftrace_ops_control_func, |
4360 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, | |
4361 | INIT_REGEX_LOCK(control_ops) | |
e248491a JO |
4362 | }; |
4363 | ||
2f5f6ad9 SR |
4364 | static inline void |
4365 | __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 4366 | struct ftrace_ops *ignored, struct pt_regs *regs) |
b848914c | 4367 | { |
cdbe61bf | 4368 | struct ftrace_ops *op; |
edc15caf | 4369 | int bit; |
b848914c | 4370 | |
ccf3672d SR |
4371 | if (function_trace_stop) |
4372 | return; | |
4373 | ||
edc15caf SR |
4374 | bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); |
4375 | if (bit < 0) | |
4376 | return; | |
b1cff0ad | 4377 | |
cdbe61bf SR |
4378 | /* |
4379 | * Some of the ops may be dynamically allocated, | |
4380 | * they must be freed after a synchronize_sched(). | |
4381 | */ | |
4382 | preempt_disable_notrace(); | |
0a016409 | 4383 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
29632b10 | 4384 | if (ftrace_ops_test(op, ip, regs)) |
a1e2e31d | 4385 | op->func(ip, parent_ip, op, regs); |
0a016409 | 4386 | } while_for_each_ftrace_op(op); |
cdbe61bf | 4387 | preempt_enable_notrace(); |
edc15caf | 4388 | trace_clear_recursion(bit); |
b848914c SR |
4389 | } |
4390 | ||
2f5f6ad9 SR |
4391 | /* |
4392 | * Some archs only support passing ip and parent_ip. Even though | |
4393 | * the list function ignores the op parameter, we do not want any | |
4394 | * C side effects, where a function is called without the caller | |
4395 | * sending a third parameter. | |
a1e2e31d SR |
4396 | * Archs are to support both the regs and ftrace_ops at the same time. |
4397 | * If they support ftrace_ops, it is assumed they support regs. | |
4398 | * If call backs want to use regs, they must either check for regs | |
06aeaaea MH |
4399 | * being NULL, or CONFIG_DYNAMIC_FTRACE_WITH_REGS. |
4400 | * Note, CONFIG_DYNAMIC_FTRACE_WITH_REGS expects a full regs to be saved. | |
a1e2e31d SR |
4401 | * An architecture can pass partial regs with ftrace_ops and still |
4402 | * set the ARCH_SUPPORT_FTARCE_OPS. | |
2f5f6ad9 SR |
4403 | */ |
4404 | #if ARCH_SUPPORTS_FTRACE_OPS | |
4405 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 4406 | struct ftrace_ops *op, struct pt_regs *regs) |
2f5f6ad9 | 4407 | { |
a1e2e31d | 4408 | __ftrace_ops_list_func(ip, parent_ip, NULL, regs); |
2f5f6ad9 SR |
4409 | } |
4410 | #else | |
4411 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip) | |
4412 | { | |
a1e2e31d | 4413 | __ftrace_ops_list_func(ip, parent_ip, NULL, NULL); |
2f5f6ad9 SR |
4414 | } |
4415 | #endif | |
4416 | ||
e32d8956 | 4417 | static void clear_ftrace_swapper(void) |
978f3a45 SR |
4418 | { |
4419 | struct task_struct *p; | |
e32d8956 | 4420 | int cpu; |
978f3a45 | 4421 | |
e32d8956 SR |
4422 | get_online_cpus(); |
4423 | for_each_online_cpu(cpu) { | |
4424 | p = idle_task(cpu); | |
978f3a45 | 4425 | clear_tsk_trace_trace(p); |
e32d8956 SR |
4426 | } |
4427 | put_online_cpus(); | |
4428 | } | |
978f3a45 | 4429 | |
e32d8956 SR |
4430 | static void set_ftrace_swapper(void) |
4431 | { | |
4432 | struct task_struct *p; | |
4433 | int cpu; | |
4434 | ||
4435 | get_online_cpus(); | |
4436 | for_each_online_cpu(cpu) { | |
4437 | p = idle_task(cpu); | |
4438 | set_tsk_trace_trace(p); | |
4439 | } | |
4440 | put_online_cpus(); | |
978f3a45 SR |
4441 | } |
4442 | ||
e32d8956 SR |
4443 | static void clear_ftrace_pid(struct pid *pid) |
4444 | { | |
4445 | struct task_struct *p; | |
4446 | ||
229c4ef8 | 4447 | rcu_read_lock(); |
e32d8956 SR |
4448 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
4449 | clear_tsk_trace_trace(p); | |
4450 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 ON |
4451 | rcu_read_unlock(); |
4452 | ||
e32d8956 SR |
4453 | put_pid(pid); |
4454 | } | |
4455 | ||
4456 | static void set_ftrace_pid(struct pid *pid) | |
978f3a45 SR |
4457 | { |
4458 | struct task_struct *p; | |
4459 | ||
229c4ef8 | 4460 | rcu_read_lock(); |
978f3a45 SR |
4461 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
4462 | set_tsk_trace_trace(p); | |
4463 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 | 4464 | rcu_read_unlock(); |
978f3a45 SR |
4465 | } |
4466 | ||
756d17ee | 4467 | static void clear_ftrace_pid_task(struct pid *pid) |
e32d8956 | 4468 | { |
756d17ee | 4469 | if (pid == ftrace_swapper_pid) |
e32d8956 SR |
4470 | clear_ftrace_swapper(); |
4471 | else | |
756d17ee | 4472 | clear_ftrace_pid(pid); |
e32d8956 SR |
4473 | } |
4474 | ||
4475 | static void set_ftrace_pid_task(struct pid *pid) | |
4476 | { | |
4477 | if (pid == ftrace_swapper_pid) | |
4478 | set_ftrace_swapper(); | |
4479 | else | |
4480 | set_ftrace_pid(pid); | |
4481 | } | |
4482 | ||
756d17ee | 4483 | static int ftrace_pid_add(int p) |
df4fc315 | 4484 | { |
978f3a45 | 4485 | struct pid *pid; |
756d17ee | 4486 | struct ftrace_pid *fpid; |
4487 | int ret = -EINVAL; | |
df4fc315 | 4488 | |
756d17ee | 4489 | mutex_lock(&ftrace_lock); |
df4fc315 | 4490 | |
756d17ee | 4491 | if (!p) |
4492 | pid = ftrace_swapper_pid; | |
4493 | else | |
4494 | pid = find_get_pid(p); | |
df4fc315 | 4495 | |
756d17ee | 4496 | if (!pid) |
4497 | goto out; | |
df4fc315 | 4498 | |
756d17ee | 4499 | ret = 0; |
df4fc315 | 4500 | |
756d17ee | 4501 | list_for_each_entry(fpid, &ftrace_pids, list) |
4502 | if (fpid->pid == pid) | |
4503 | goto out_put; | |
978f3a45 | 4504 | |
756d17ee | 4505 | ret = -ENOMEM; |
df4fc315 | 4506 | |
756d17ee | 4507 | fpid = kmalloc(sizeof(*fpid), GFP_KERNEL); |
4508 | if (!fpid) | |
4509 | goto out_put; | |
df4fc315 | 4510 | |
756d17ee | 4511 | list_add(&fpid->list, &ftrace_pids); |
4512 | fpid->pid = pid; | |
0ef8cde5 | 4513 | |
756d17ee | 4514 | set_ftrace_pid_task(pid); |
978f3a45 | 4515 | |
756d17ee | 4516 | ftrace_update_pid_func(); |
4517 | ftrace_startup_enable(0); | |
4518 | ||
4519 | mutex_unlock(&ftrace_lock); | |
4520 | return 0; | |
4521 | ||
4522 | out_put: | |
4523 | if (pid != ftrace_swapper_pid) | |
4524 | put_pid(pid); | |
978f3a45 | 4525 | |
756d17ee | 4526 | out: |
4527 | mutex_unlock(&ftrace_lock); | |
4528 | return ret; | |
4529 | } | |
4530 | ||
4531 | static void ftrace_pid_reset(void) | |
4532 | { | |
4533 | struct ftrace_pid *fpid, *safe; | |
978f3a45 | 4534 | |
756d17ee | 4535 | mutex_lock(&ftrace_lock); |
4536 | list_for_each_entry_safe(fpid, safe, &ftrace_pids, list) { | |
4537 | struct pid *pid = fpid->pid; | |
4538 | ||
4539 | clear_ftrace_pid_task(pid); | |
4540 | ||
4541 | list_del(&fpid->list); | |
4542 | kfree(fpid); | |
df4fc315 SR |
4543 | } |
4544 | ||
df4fc315 SR |
4545 | ftrace_update_pid_func(); |
4546 | ftrace_startup_enable(0); | |
4547 | ||
e6ea44e9 | 4548 | mutex_unlock(&ftrace_lock); |
756d17ee | 4549 | } |
df4fc315 | 4550 | |
756d17ee | 4551 | static void *fpid_start(struct seq_file *m, loff_t *pos) |
4552 | { | |
4553 | mutex_lock(&ftrace_lock); | |
4554 | ||
4555 | if (list_empty(&ftrace_pids) && (!*pos)) | |
4556 | return (void *) 1; | |
4557 | ||
4558 | return seq_list_start(&ftrace_pids, *pos); | |
4559 | } | |
4560 | ||
4561 | static void *fpid_next(struct seq_file *m, void *v, loff_t *pos) | |
4562 | { | |
4563 | if (v == (void *)1) | |
4564 | return NULL; | |
4565 | ||
4566 | return seq_list_next(v, &ftrace_pids, pos); | |
4567 | } | |
4568 | ||
4569 | static void fpid_stop(struct seq_file *m, void *p) | |
4570 | { | |
4571 | mutex_unlock(&ftrace_lock); | |
4572 | } | |
4573 | ||
4574 | static int fpid_show(struct seq_file *m, void *v) | |
4575 | { | |
4576 | const struct ftrace_pid *fpid = list_entry(v, struct ftrace_pid, list); | |
4577 | ||
4578 | if (v == (void *)1) { | |
4579 | seq_printf(m, "no pid\n"); | |
4580 | return 0; | |
4581 | } | |
4582 | ||
4583 | if (fpid->pid == ftrace_swapper_pid) | |
4584 | seq_printf(m, "swapper tasks\n"); | |
4585 | else | |
4586 | seq_printf(m, "%u\n", pid_vnr(fpid->pid)); | |
4587 | ||
4588 | return 0; | |
4589 | } | |
4590 | ||
4591 | static const struct seq_operations ftrace_pid_sops = { | |
4592 | .start = fpid_start, | |
4593 | .next = fpid_next, | |
4594 | .stop = fpid_stop, | |
4595 | .show = fpid_show, | |
4596 | }; | |
4597 | ||
4598 | static int | |
4599 | ftrace_pid_open(struct inode *inode, struct file *file) | |
4600 | { | |
4601 | int ret = 0; | |
4602 | ||
4603 | if ((file->f_mode & FMODE_WRITE) && | |
4604 | (file->f_flags & O_TRUNC)) | |
4605 | ftrace_pid_reset(); | |
4606 | ||
4607 | if (file->f_mode & FMODE_READ) | |
4608 | ret = seq_open(file, &ftrace_pid_sops); | |
4609 | ||
4610 | return ret; | |
4611 | } | |
4612 | ||
df4fc315 SR |
4613 | static ssize_t |
4614 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
4615 | size_t cnt, loff_t *ppos) | |
4616 | { | |
457dc928 | 4617 | char buf[64], *tmp; |
df4fc315 SR |
4618 | long val; |
4619 | int ret; | |
4620 | ||
4621 | if (cnt >= sizeof(buf)) | |
4622 | return -EINVAL; | |
4623 | ||
4624 | if (copy_from_user(&buf, ubuf, cnt)) | |
4625 | return -EFAULT; | |
4626 | ||
4627 | buf[cnt] = 0; | |
4628 | ||
756d17ee | 4629 | /* |
4630 | * Allow "echo > set_ftrace_pid" or "echo -n '' > set_ftrace_pid" | |
4631 | * to clean the filter quietly. | |
4632 | */ | |
457dc928 IM |
4633 | tmp = strstrip(buf); |
4634 | if (strlen(tmp) == 0) | |
756d17ee | 4635 | return 1; |
4636 | ||
bcd83ea6 | 4637 | ret = kstrtol(tmp, 10, &val); |
df4fc315 SR |
4638 | if (ret < 0) |
4639 | return ret; | |
4640 | ||
756d17ee | 4641 | ret = ftrace_pid_add(val); |
df4fc315 | 4642 | |
756d17ee | 4643 | return ret ? ret : cnt; |
4644 | } | |
df4fc315 | 4645 | |
756d17ee | 4646 | static int |
4647 | ftrace_pid_release(struct inode *inode, struct file *file) | |
4648 | { | |
4649 | if (file->f_mode & FMODE_READ) | |
4650 | seq_release(inode, file); | |
df4fc315 | 4651 | |
756d17ee | 4652 | return 0; |
df4fc315 SR |
4653 | } |
4654 | ||
5e2336a0 | 4655 | static const struct file_operations ftrace_pid_fops = { |
756d17ee | 4656 | .open = ftrace_pid_open, |
4657 | .write = ftrace_pid_write, | |
4658 | .read = seq_read, | |
6a76f8c0 | 4659 | .llseek = ftrace_filter_lseek, |
756d17ee | 4660 | .release = ftrace_pid_release, |
df4fc315 SR |
4661 | }; |
4662 | ||
4663 | static __init int ftrace_init_debugfs(void) | |
4664 | { | |
4665 | struct dentry *d_tracer; | |
df4fc315 SR |
4666 | |
4667 | d_tracer = tracing_init_dentry(); | |
4668 | if (!d_tracer) | |
4669 | return 0; | |
4670 | ||
4671 | ftrace_init_dyn_debugfs(d_tracer); | |
4672 | ||
5452af66 FW |
4673 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
4674 | NULL, &ftrace_pid_fops); | |
493762fc SR |
4675 | |
4676 | ftrace_profile_debugfs(d_tracer); | |
4677 | ||
df4fc315 SR |
4678 | return 0; |
4679 | } | |
df4fc315 SR |
4680 | fs_initcall(ftrace_init_debugfs); |
4681 | ||
a2bb6a3d | 4682 | /** |
81adbdc0 | 4683 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
4684 | * |
4685 | * This function should be used by panic code. It stops ftrace | |
4686 | * but in a not so nice way. If you need to simply kill ftrace | |
4687 | * from a non-atomic section, use ftrace_kill. | |
4688 | */ | |
81adbdc0 | 4689 | void ftrace_kill(void) |
a2bb6a3d SR |
4690 | { |
4691 | ftrace_disabled = 1; | |
4692 | ftrace_enabled = 0; | |
a2bb6a3d SR |
4693 | clear_ftrace_function(); |
4694 | } | |
4695 | ||
e0a413f6 SR |
4696 | /** |
4697 | * Test if ftrace is dead or not. | |
4698 | */ | |
4699 | int ftrace_is_dead(void) | |
4700 | { | |
4701 | return ftrace_disabled; | |
4702 | } | |
4703 | ||
16444a8a | 4704 | /** |
3d083395 SR |
4705 | * register_ftrace_function - register a function for profiling |
4706 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 4707 | * |
3d083395 SR |
4708 | * Register a function to be called by all functions in the |
4709 | * kernel. | |
4710 | * | |
4711 | * Note: @ops->func and all the functions it calls must be labeled | |
4712 | * with "notrace", otherwise it will go into a | |
4713 | * recursive loop. | |
16444a8a | 4714 | */ |
3d083395 | 4715 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 4716 | { |
45a4a237 | 4717 | int ret = -1; |
4eebcc81 | 4718 | |
f04f24fb MH |
4719 | ftrace_ops_init(ops); |
4720 | ||
e6ea44e9 | 4721 | mutex_lock(&ftrace_lock); |
e7d3737e | 4722 | |
2940c25b | 4723 | ret = ftrace_startup(ops, 0); |
b848914c | 4724 | |
e6ea44e9 | 4725 | mutex_unlock(&ftrace_lock); |
8d240dd8 | 4726 | |
b0fc494f | 4727 | return ret; |
3d083395 | 4728 | } |
cdbe61bf | 4729 | EXPORT_SYMBOL_GPL(register_ftrace_function); |
3d083395 SR |
4730 | |
4731 | /** | |
32632920 | 4732 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
4733 | * @ops - ops structure that holds the function to unregister |
4734 | * | |
4735 | * Unregister a function that was added to be called by ftrace profiling. | |
4736 | */ | |
4737 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
4738 | { | |
4739 | int ret; | |
4740 | ||
e6ea44e9 | 4741 | mutex_lock(&ftrace_lock); |
2940c25b | 4742 | ret = ftrace_shutdown(ops, 0); |
e6ea44e9 | 4743 | mutex_unlock(&ftrace_lock); |
b0fc494f SR |
4744 | |
4745 | return ret; | |
4746 | } | |
cdbe61bf | 4747 | EXPORT_SYMBOL_GPL(unregister_ftrace_function); |
b0fc494f | 4748 | |
e309b41d | 4749 | int |
b0fc494f | 4750 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
8d65af78 | 4751 | void __user *buffer, size_t *lenp, |
b0fc494f SR |
4752 | loff_t *ppos) |
4753 | { | |
45a4a237 | 4754 | int ret = -ENODEV; |
4eebcc81 | 4755 | |
e6ea44e9 | 4756 | mutex_lock(&ftrace_lock); |
b0fc494f | 4757 | |
45a4a237 SR |
4758 | if (unlikely(ftrace_disabled)) |
4759 | goto out; | |
4760 | ||
4761 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
b0fc494f | 4762 | |
a32c7765 | 4763 | if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) |
b0fc494f SR |
4764 | goto out; |
4765 | ||
a32c7765 | 4766 | last_ftrace_enabled = !!ftrace_enabled; |
b0fc494f SR |
4767 | |
4768 | if (ftrace_enabled) { | |
4769 | ||
4770 | ftrace_startup_sysctl(); | |
4771 | ||
4772 | /* we are starting ftrace again */ | |
5000c418 JK |
4773 | if (ftrace_ops_list != &ftrace_list_end) |
4774 | update_ftrace_function(); | |
b0fc494f SR |
4775 | |
4776 | } else { | |
4777 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
4778 | ftrace_trace_function = ftrace_stub; | |
4779 | ||
4780 | ftrace_shutdown_sysctl(); | |
4781 | } | |
4782 | ||
4783 | out: | |
e6ea44e9 | 4784 | mutex_unlock(&ftrace_lock); |
3d083395 | 4785 | return ret; |
16444a8a | 4786 | } |
f17845e5 | 4787 | |
fb52607a | 4788 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 4789 | |
597af815 | 4790 | static int ftrace_graph_active; |
4a2b8dda | 4791 | static struct notifier_block ftrace_suspend_notifier; |
e7d3737e | 4792 | |
e49dc19c SR |
4793 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
4794 | { | |
4795 | return 0; | |
4796 | } | |
4797 | ||
287b6e68 FW |
4798 | /* The callbacks that hook a function */ |
4799 | trace_func_graph_ret_t ftrace_graph_return = | |
4800 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 4801 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
1499a3eb | 4802 | static trace_func_graph_ent_t __ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
4803 | |
4804 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
4805 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
4806 | { | |
4807 | int i; | |
4808 | int ret = 0; | |
4809 | unsigned long flags; | |
4810 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; | |
4811 | struct task_struct *g, *t; | |
4812 | ||
4813 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
4814 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
4815 | * sizeof(struct ftrace_ret_stack), | |
4816 | GFP_KERNEL); | |
4817 | if (!ret_stack_list[i]) { | |
4818 | start = 0; | |
4819 | end = i; | |
4820 | ret = -ENOMEM; | |
4821 | goto free; | |
4822 | } | |
4823 | } | |
4824 | ||
4825 | read_lock_irqsave(&tasklist_lock, flags); | |
4826 | do_each_thread(g, t) { | |
4827 | if (start == end) { | |
4828 | ret = -EAGAIN; | |
4829 | goto unlock; | |
4830 | } | |
4831 | ||
4832 | if (t->ret_stack == NULL) { | |
380c4b14 | 4833 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 | 4834 | atomic_set(&t->trace_overrun, 0); |
26c01624 SR |
4835 | t->curr_ret_stack = -1; |
4836 | /* Make sure the tasks see the -1 first: */ | |
4837 | smp_wmb(); | |
4838 | t->ret_stack = ret_stack_list[start++]; | |
f201ae23 FW |
4839 | } |
4840 | } while_each_thread(g, t); | |
4841 | ||
4842 | unlock: | |
4843 | read_unlock_irqrestore(&tasklist_lock, flags); | |
4844 | free: | |
4845 | for (i = start; i < end; i++) | |
4846 | kfree(ret_stack_list[i]); | |
4847 | return ret; | |
4848 | } | |
4849 | ||
8aef2d28 | 4850 | static void |
38516ab5 SR |
4851 | ftrace_graph_probe_sched_switch(void *ignore, |
4852 | struct task_struct *prev, struct task_struct *next) | |
8aef2d28 SR |
4853 | { |
4854 | unsigned long long timestamp; | |
4855 | int index; | |
4856 | ||
be6f164a SR |
4857 | /* |
4858 | * Does the user want to count the time a function was asleep. | |
4859 | * If so, do not update the time stamps. | |
4860 | */ | |
4861 | if (trace_flags & TRACE_ITER_SLEEP_TIME) | |
4862 | return; | |
4863 | ||
8aef2d28 SR |
4864 | timestamp = trace_clock_local(); |
4865 | ||
4866 | prev->ftrace_timestamp = timestamp; | |
4867 | ||
4868 | /* only process tasks that we timestamped */ | |
4869 | if (!next->ftrace_timestamp) | |
4870 | return; | |
4871 | ||
4872 | /* | |
4873 | * Update all the counters in next to make up for the | |
4874 | * time next was sleeping. | |
4875 | */ | |
4876 | timestamp -= next->ftrace_timestamp; | |
4877 | ||
4878 | for (index = next->curr_ret_stack; index >= 0; index--) | |
4879 | next->ret_stack[index].calltime += timestamp; | |
4880 | } | |
4881 | ||
f201ae23 | 4882 | /* Allocate a return stack for each task */ |
fb52607a | 4883 | static int start_graph_tracing(void) |
f201ae23 FW |
4884 | { |
4885 | struct ftrace_ret_stack **ret_stack_list; | |
5b058bcd | 4886 | int ret, cpu; |
f201ae23 FW |
4887 | |
4888 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
4889 | sizeof(struct ftrace_ret_stack *), | |
4890 | GFP_KERNEL); | |
4891 | ||
4892 | if (!ret_stack_list) | |
4893 | return -ENOMEM; | |
4894 | ||
5b058bcd | 4895 | /* The cpu_boot init_task->ret_stack will never be freed */ |
179c498a SR |
4896 | for_each_online_cpu(cpu) { |
4897 | if (!idle_task(cpu)->ret_stack) | |
868baf07 | 4898 | ftrace_graph_init_idle_task(idle_task(cpu), cpu); |
179c498a | 4899 | } |
5b058bcd | 4900 | |
f201ae23 FW |
4901 | do { |
4902 | ret = alloc_retstack_tasklist(ret_stack_list); | |
4903 | } while (ret == -EAGAIN); | |
4904 | ||
8aef2d28 | 4905 | if (!ret) { |
38516ab5 | 4906 | ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
8aef2d28 SR |
4907 | if (ret) |
4908 | pr_info("ftrace_graph: Couldn't activate tracepoint" | |
4909 | " probe to kernel_sched_switch\n"); | |
4910 | } | |
4911 | ||
f201ae23 FW |
4912 | kfree(ret_stack_list); |
4913 | return ret; | |
4914 | } | |
4915 | ||
4a2b8dda FW |
4916 | /* |
4917 | * Hibernation protection. | |
4918 | * The state of the current task is too much unstable during | |
4919 | * suspend/restore to disk. We want to protect against that. | |
4920 | */ | |
4921 | static int | |
4922 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, | |
4923 | void *unused) | |
4924 | { | |
4925 | switch (state) { | |
4926 | case PM_HIBERNATION_PREPARE: | |
4927 | pause_graph_tracing(); | |
4928 | break; | |
4929 | ||
4930 | case PM_POST_HIBERNATION: | |
4931 | unpause_graph_tracing(); | |
4932 | break; | |
4933 | } | |
4934 | return NOTIFY_DONE; | |
4935 | } | |
4936 | ||
2940c25b SRRH |
4937 | /* Just a place holder for function graph */ |
4938 | static struct ftrace_ops fgraph_ops __read_mostly = { | |
4939 | .func = ftrace_stub, | |
4940 | .flags = FTRACE_OPS_FL_STUB | FTRACE_OPS_FL_GLOBAL | | |
4941 | FTRACE_OPS_FL_RECURSION_SAFE, | |
4942 | }; | |
4943 | ||
1499a3eb SR |
4944 | static int ftrace_graph_entry_test(struct ftrace_graph_ent *trace) |
4945 | { | |
4946 | if (!ftrace_ops_test(&global_ops, trace->func, NULL)) | |
4947 | return 0; | |
4948 | return __ftrace_graph_entry(trace); | |
4949 | } | |
4950 | ||
4951 | /* | |
4952 | * The function graph tracer should only trace the functions defined | |
4953 | * by set_ftrace_filter and set_ftrace_notrace. If another function | |
4954 | * tracer ops is registered, the graph tracer requires testing the | |
4955 | * function against the global ops, and not just trace any function | |
4956 | * that any ftrace_ops registered. | |
4957 | */ | |
4958 | static void update_function_graph_func(void) | |
4959 | { | |
4960 | if (ftrace_ops_list == &ftrace_list_end || | |
4961 | (ftrace_ops_list == &global_ops && | |
4962 | global_ops.next == &ftrace_list_end)) | |
4963 | ftrace_graph_entry = __ftrace_graph_entry; | |
4964 | else | |
4965 | ftrace_graph_entry = ftrace_graph_entry_test; | |
4966 | } | |
4967 | ||
287b6e68 FW |
4968 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
4969 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 4970 | { |
e7d3737e FW |
4971 | int ret = 0; |
4972 | ||
e6ea44e9 | 4973 | mutex_lock(&ftrace_lock); |
e7d3737e | 4974 | |
05ce5818 | 4975 | /* we currently allow only one tracer registered at a time */ |
597af815 | 4976 | if (ftrace_graph_active) { |
05ce5818 SR |
4977 | ret = -EBUSY; |
4978 | goto out; | |
4979 | } | |
4980 | ||
4a2b8dda FW |
4981 | ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call; |
4982 | register_pm_notifier(&ftrace_suspend_notifier); | |
4983 | ||
597af815 | 4984 | ftrace_graph_active++; |
fb52607a | 4985 | ret = start_graph_tracing(); |
f201ae23 | 4986 | if (ret) { |
597af815 | 4987 | ftrace_graph_active--; |
f201ae23 FW |
4988 | goto out; |
4989 | } | |
e53a6319 | 4990 | |
287b6e68 | 4991 | ftrace_graph_return = retfunc; |
1499a3eb SR |
4992 | |
4993 | /* | |
4994 | * Update the indirect function to the entryfunc, and the | |
4995 | * function that gets called to the entry_test first. Then | |
4996 | * call the update fgraph entry function to determine if | |
4997 | * the entryfunc should be called directly or not. | |
4998 | */ | |
4999 | __ftrace_graph_entry = entryfunc; | |
5000 | ftrace_graph_entry = ftrace_graph_entry_test; | |
5001 | update_function_graph_func(); | |
e53a6319 | 5002 | |
2940c25b | 5003 | ret = ftrace_startup(&fgraph_ops, FTRACE_START_FUNC_RET); |
e7d3737e FW |
5004 | |
5005 | out: | |
e6ea44e9 | 5006 | mutex_unlock(&ftrace_lock); |
e7d3737e | 5007 | return ret; |
15e6cb36 FW |
5008 | } |
5009 | ||
fb52607a | 5010 | void unregister_ftrace_graph(void) |
15e6cb36 | 5011 | { |
e6ea44e9 | 5012 | mutex_lock(&ftrace_lock); |
e7d3737e | 5013 | |
597af815 | 5014 | if (unlikely(!ftrace_graph_active)) |
2aad1b76 SR |
5015 | goto out; |
5016 | ||
597af815 | 5017 | ftrace_graph_active--; |
287b6e68 | 5018 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; |
e49dc19c | 5019 | ftrace_graph_entry = ftrace_graph_entry_stub; |
1499a3eb | 5020 | __ftrace_graph_entry = ftrace_graph_entry_stub; |
2940c25b | 5021 | ftrace_shutdown(&fgraph_ops, FTRACE_STOP_FUNC_RET); |
4a2b8dda | 5022 | unregister_pm_notifier(&ftrace_suspend_notifier); |
38516ab5 | 5023 | unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
e7d3737e | 5024 | |
2aad1b76 | 5025 | out: |
e6ea44e9 | 5026 | mutex_unlock(&ftrace_lock); |
15e6cb36 | 5027 | } |
f201ae23 | 5028 | |
868baf07 SR |
5029 | static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack); |
5030 | ||
5031 | static void | |
5032 | graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack) | |
5033 | { | |
5034 | atomic_set(&t->tracing_graph_pause, 0); | |
5035 | atomic_set(&t->trace_overrun, 0); | |
5036 | t->ftrace_timestamp = 0; | |
25985edc | 5037 | /* make curr_ret_stack visible before we add the ret_stack */ |
868baf07 SR |
5038 | smp_wmb(); |
5039 | t->ret_stack = ret_stack; | |
5040 | } | |
5041 | ||
5042 | /* | |
5043 | * Allocate a return stack for the idle task. May be the first | |
5044 | * time through, or it may be done by CPU hotplug online. | |
5045 | */ | |
5046 | void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) | |
5047 | { | |
5048 | t->curr_ret_stack = -1; | |
5049 | /* | |
5050 | * The idle task has no parent, it either has its own | |
5051 | * stack or no stack at all. | |
5052 | */ | |
5053 | if (t->ret_stack) | |
5054 | WARN_ON(t->ret_stack != per_cpu(idle_ret_stack, cpu)); | |
5055 | ||
5056 | if (ftrace_graph_active) { | |
5057 | struct ftrace_ret_stack *ret_stack; | |
5058 | ||
5059 | ret_stack = per_cpu(idle_ret_stack, cpu); | |
5060 | if (!ret_stack) { | |
5061 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
5062 | * sizeof(struct ftrace_ret_stack), | |
5063 | GFP_KERNEL); | |
5064 | if (!ret_stack) | |
5065 | return; | |
5066 | per_cpu(idle_ret_stack, cpu) = ret_stack; | |
5067 | } | |
5068 | graph_init_task(t, ret_stack); | |
5069 | } | |
5070 | } | |
5071 | ||
f201ae23 | 5072 | /* Allocate a return stack for newly created task */ |
fb52607a | 5073 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 5074 | { |
84047e36 SR |
5075 | /* Make sure we do not use the parent ret_stack */ |
5076 | t->ret_stack = NULL; | |
ea14eb71 | 5077 | t->curr_ret_stack = -1; |
84047e36 | 5078 | |
597af815 | 5079 | if (ftrace_graph_active) { |
82310a32 SR |
5080 | struct ftrace_ret_stack *ret_stack; |
5081 | ||
5082 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
f201ae23 FW |
5083 | * sizeof(struct ftrace_ret_stack), |
5084 | GFP_KERNEL); | |
82310a32 | 5085 | if (!ret_stack) |
f201ae23 | 5086 | return; |
868baf07 | 5087 | graph_init_task(t, ret_stack); |
84047e36 | 5088 | } |
f201ae23 FW |
5089 | } |
5090 | ||
fb52607a | 5091 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 5092 | { |
eae849ca FW |
5093 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
5094 | ||
f201ae23 | 5095 | t->ret_stack = NULL; |
eae849ca FW |
5096 | /* NULL must become visible to IRQs before we free it: */ |
5097 | barrier(); | |
5098 | ||
5099 | kfree(ret_stack); | |
f201ae23 | 5100 | } |
14a866c5 SR |
5101 | |
5102 | void ftrace_graph_stop(void) | |
5103 | { | |
5104 | ftrace_stop(); | |
5105 | } | |
15e6cb36 | 5106 | #endif |