]>
Commit | Line | Data |
---|---|---|
16444a8a ACM |
1 | /* |
2 | * Infrastructure for profiling code inserted by 'gcc -pg'. | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2004-2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally ported from the -rt patch by: | |
8 | * Copyright (C) 2007 Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code in the latency_tracer, that is: | |
11 | * | |
12 | * Copyright (C) 2004-2006 Ingo Molnar | |
6d49e352 | 13 | * Copyright (C) 2004 Nadia Yvette Chambers |
16444a8a ACM |
14 | */ |
15 | ||
3d083395 SR |
16 | #include <linux/stop_machine.h> |
17 | #include <linux/clocksource.h> | |
29930025 | 18 | #include <linux/sched/task.h> |
3d083395 | 19 | #include <linux/kallsyms.h> |
5072c59f | 20 | #include <linux/seq_file.h> |
4a2b8dda | 21 | #include <linux/suspend.h> |
8434dc93 | 22 | #include <linux/tracefs.h> |
3d083395 | 23 | #include <linux/hardirq.h> |
2d8b820b | 24 | #include <linux/kthread.h> |
5072c59f | 25 | #include <linux/uaccess.h> |
5855fead | 26 | #include <linux/bsearch.h> |
56d82e00 | 27 | #include <linux/module.h> |
2d8b820b | 28 | #include <linux/ftrace.h> |
b0fc494f | 29 | #include <linux/sysctl.h> |
5a0e3ad6 | 30 | #include <linux/slab.h> |
5072c59f | 31 | #include <linux/ctype.h> |
68950619 | 32 | #include <linux/sort.h> |
3d083395 | 33 | #include <linux/list.h> |
59df055f | 34 | #include <linux/hash.h> |
3f379b03 | 35 | #include <linux/rcupdate.h> |
3d083395 | 36 | |
ad8d75ff | 37 | #include <trace/events/sched.h> |
8aef2d28 | 38 | |
b80f0f6c | 39 | #include <asm/sections.h> |
2af15d6a | 40 | #include <asm/setup.h> |
395a59d0 | 41 | |
0706f1c4 | 42 | #include "trace_output.h" |
bac429f0 | 43 | #include "trace_stat.h" |
16444a8a | 44 | |
6912896e | 45 | #define FTRACE_WARN_ON(cond) \ |
0778d9ad SR |
46 | ({ \ |
47 | int ___r = cond; \ | |
48 | if (WARN_ON(___r)) \ | |
6912896e | 49 | ftrace_kill(); \ |
0778d9ad SR |
50 | ___r; \ |
51 | }) | |
6912896e SR |
52 | |
53 | #define FTRACE_WARN_ON_ONCE(cond) \ | |
0778d9ad SR |
54 | ({ \ |
55 | int ___r = cond; \ | |
56 | if (WARN_ON_ONCE(___r)) \ | |
6912896e | 57 | ftrace_kill(); \ |
0778d9ad SR |
58 | ___r; \ |
59 | }) | |
6912896e | 60 | |
8fc0c701 SR |
61 | /* hash bits for specific function selection */ |
62 | #define FTRACE_HASH_BITS 7 | |
63 | #define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS) | |
33dc9b12 SR |
64 | #define FTRACE_HASH_DEFAULT_BITS 10 |
65 | #define FTRACE_HASH_MAX_BITS 12 | |
8fc0c701 | 66 | |
f04f24fb | 67 | #ifdef CONFIG_DYNAMIC_FTRACE |
33b7f99c SRRH |
68 | #define INIT_OPS_HASH(opsname) \ |
69 | .func_hash = &opsname.local_hash, \ | |
70 | .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock), | |
5f151b24 SRRH |
71 | #define ASSIGN_OPS_HASH(opsname, val) \ |
72 | .func_hash = val, \ | |
73 | .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock), | |
f04f24fb | 74 | #else |
33b7f99c | 75 | #define INIT_OPS_HASH(opsname) |
5f151b24 | 76 | #define ASSIGN_OPS_HASH(opsname, val) |
f04f24fb MH |
77 | #endif |
78 | ||
2f5f6ad9 SR |
79 | static struct ftrace_ops ftrace_list_end __read_mostly = { |
80 | .func = ftrace_stub, | |
395b97a3 | 81 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_STUB, |
33b7f99c | 82 | INIT_OPS_HASH(ftrace_list_end) |
2f5f6ad9 SR |
83 | }; |
84 | ||
4eebcc81 SR |
85 | /* ftrace_enabled is a method to turn ftrace on or off */ |
86 | int ftrace_enabled __read_mostly; | |
d61f82d0 | 87 | static int last_ftrace_enabled; |
b0fc494f | 88 | |
2f5f6ad9 SR |
89 | /* Current function tracing op */ |
90 | struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end; | |
405e1d83 SRRH |
91 | /* What to set function_trace_op to */ |
92 | static struct ftrace_ops *set_function_trace_op; | |
60a7ecf4 | 93 | |
345ddcc8 | 94 | static bool ftrace_pids_enabled(struct ftrace_ops *ops) |
e3eea140 | 95 | { |
345ddcc8 SRRH |
96 | struct trace_array *tr; |
97 | ||
98 | if (!(ops->flags & FTRACE_OPS_FL_PID) || !ops->private) | |
99 | return false; | |
100 | ||
101 | tr = ops->private; | |
102 | ||
103 | return tr->function_pids != NULL; | |
e3eea140 SRRH |
104 | } |
105 | ||
106 | static void ftrace_update_trampoline(struct ftrace_ops *ops); | |
107 | ||
4eebcc81 SR |
108 | /* |
109 | * ftrace_disabled is set when an anomaly is discovered. | |
110 | * ftrace_disabled is much stronger than ftrace_enabled. | |
111 | */ | |
112 | static int ftrace_disabled __read_mostly; | |
113 | ||
52baf119 | 114 | static DEFINE_MUTEX(ftrace_lock); |
b0fc494f | 115 | |
b848914c | 116 | static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end; |
16444a8a | 117 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; |
2b499381 | 118 | static struct ftrace_ops global_ops; |
16444a8a | 119 | |
2f5f6ad9 SR |
120 | #if ARCH_SUPPORTS_FTRACE_OPS |
121 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 122 | struct ftrace_ops *op, struct pt_regs *regs); |
2f5f6ad9 SR |
123 | #else |
124 | /* See comment below, where ftrace_ops_list_func is defined */ | |
125 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip); | |
126 | #define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops) | |
127 | #endif | |
b848914c | 128 | |
0a016409 SR |
129 | /* |
130 | * Traverse the ftrace_global_list, invoking all entries. The reason that we | |
1bb539ca | 131 | * can use rcu_dereference_raw_notrace() is that elements removed from this list |
0a016409 | 132 | * are simply leaked, so there is no need to interact with a grace-period |
1bb539ca | 133 | * mechanism. The rcu_dereference_raw_notrace() calls are needed to handle |
0a016409 SR |
134 | * concurrent insertions into the ftrace_global_list. |
135 | * | |
136 | * Silly Alpha and silly pointer-speculation compiler optimizations! | |
137 | */ | |
138 | #define do_for_each_ftrace_op(op, list) \ | |
1bb539ca | 139 | op = rcu_dereference_raw_notrace(list); \ |
0a016409 SR |
140 | do |
141 | ||
142 | /* | |
143 | * Optimized for just a single item in the list (as that is the normal case). | |
144 | */ | |
145 | #define while_for_each_ftrace_op(op) \ | |
1bb539ca | 146 | while (likely(op = rcu_dereference_raw_notrace((op)->next)) && \ |
0a016409 SR |
147 | unlikely((op) != &ftrace_list_end)) |
148 | ||
f04f24fb MH |
149 | static inline void ftrace_ops_init(struct ftrace_ops *ops) |
150 | { | |
151 | #ifdef CONFIG_DYNAMIC_FTRACE | |
152 | if (!(ops->flags & FTRACE_OPS_FL_INITIALIZED)) { | |
33b7f99c SRRH |
153 | mutex_init(&ops->local_hash.regex_lock); |
154 | ops->func_hash = &ops->local_hash; | |
f04f24fb MH |
155 | ops->flags |= FTRACE_OPS_FL_INITIALIZED; |
156 | } | |
157 | #endif | |
158 | } | |
159 | ||
ea701f11 SR |
160 | /** |
161 | * ftrace_nr_registered_ops - return number of ops registered | |
162 | * | |
163 | * Returns the number of ftrace_ops registered and tracing functions | |
164 | */ | |
165 | int ftrace_nr_registered_ops(void) | |
166 | { | |
167 | struct ftrace_ops *ops; | |
168 | int cnt = 0; | |
169 | ||
170 | mutex_lock(&ftrace_lock); | |
171 | ||
172 | for (ops = ftrace_ops_list; | |
173 | ops != &ftrace_list_end; ops = ops->next) | |
174 | cnt++; | |
175 | ||
176 | mutex_unlock(&ftrace_lock); | |
177 | ||
178 | return cnt; | |
179 | } | |
180 | ||
2f5f6ad9 | 181 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 182 | struct ftrace_ops *op, struct pt_regs *regs) |
df4fc315 | 183 | { |
345ddcc8 SRRH |
184 | struct trace_array *tr = op->private; |
185 | ||
186 | if (tr && this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid)) | |
df4fc315 SR |
187 | return; |
188 | ||
e3eea140 | 189 | op->saved_func(ip, parent_ip, op, regs); |
df4fc315 SR |
190 | } |
191 | ||
16444a8a | 192 | /** |
3d083395 | 193 | * clear_ftrace_function - reset the ftrace function |
16444a8a | 194 | * |
3d083395 SR |
195 | * This NULLs the ftrace function and in essence stops |
196 | * tracing. There may be lag | |
16444a8a | 197 | */ |
3d083395 | 198 | void clear_ftrace_function(void) |
16444a8a | 199 | { |
3d083395 SR |
200 | ftrace_trace_function = ftrace_stub; |
201 | } | |
202 | ||
ba27f2bc | 203 | static void per_cpu_ops_disable_all(struct ftrace_ops *ops) |
e248491a JO |
204 | { |
205 | int cpu; | |
206 | ||
207 | for_each_possible_cpu(cpu) | |
208 | *per_cpu_ptr(ops->disabled, cpu) = 1; | |
209 | } | |
210 | ||
ba27f2bc | 211 | static int per_cpu_ops_alloc(struct ftrace_ops *ops) |
e248491a JO |
212 | { |
213 | int __percpu *disabled; | |
214 | ||
ba27f2bc SRRH |
215 | if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_PER_CPU))) |
216 | return -EINVAL; | |
217 | ||
e248491a JO |
218 | disabled = alloc_percpu(int); |
219 | if (!disabled) | |
220 | return -ENOMEM; | |
221 | ||
222 | ops->disabled = disabled; | |
ba27f2bc | 223 | per_cpu_ops_disable_all(ops); |
e248491a JO |
224 | return 0; |
225 | } | |
226 | ||
405e1d83 SRRH |
227 | static void ftrace_sync(struct work_struct *work) |
228 | { | |
229 | /* | |
230 | * This function is just a stub to implement a hard force | |
231 | * of synchronize_sched(). This requires synchronizing | |
232 | * tasks even in userspace and idle. | |
233 | * | |
234 | * Yes, function tracing is rude. | |
235 | */ | |
236 | } | |
237 | ||
238 | static void ftrace_sync_ipi(void *data) | |
239 | { | |
240 | /* Probably not needed, but do it anyway */ | |
241 | smp_rmb(); | |
242 | } | |
243 | ||
23a8e844 SRRH |
244 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
245 | static void update_function_graph_func(void); | |
55577204 SRRH |
246 | |
247 | /* Both enabled by default (can be cleared by function_graph tracer flags */ | |
248 | static bool fgraph_sleep_time = true; | |
249 | static bool fgraph_graph_time = true; | |
250 | ||
23a8e844 SRRH |
251 | #else |
252 | static inline void update_function_graph_func(void) { } | |
253 | #endif | |
254 | ||
00ccbf2f SRRH |
255 | |
256 | static ftrace_func_t ftrace_ops_get_list_func(struct ftrace_ops *ops) | |
257 | { | |
258 | /* | |
ba27f2bc | 259 | * If this is a dynamic, RCU, or per CPU ops, or we force list func, |
00ccbf2f SRRH |
260 | * then it needs to call the list anyway. |
261 | */ | |
ba27f2bc SRRH |
262 | if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_PER_CPU | |
263 | FTRACE_OPS_FL_RCU) || FTRACE_FORCE_LIST_FUNC) | |
00ccbf2f SRRH |
264 | return ftrace_ops_list_func; |
265 | ||
266 | return ftrace_ops_get_func(ops); | |
267 | } | |
268 | ||
2b499381 SR |
269 | static void update_ftrace_function(void) |
270 | { | |
271 | ftrace_func_t func; | |
272 | ||
f7aad4e1 SRRH |
273 | /* |
274 | * Prepare the ftrace_ops that the arch callback will use. | |
275 | * If there's only one ftrace_ops registered, the ftrace_ops_list | |
276 | * will point to the ops we want. | |
277 | */ | |
278 | set_function_trace_op = ftrace_ops_list; | |
279 | ||
280 | /* If there's no ftrace_ops registered, just call the stub function */ | |
281 | if (ftrace_ops_list == &ftrace_list_end) { | |
282 | func = ftrace_stub; | |
283 | ||
cdbe61bf SR |
284 | /* |
285 | * If we are at the end of the list and this ops is | |
4740974a SR |
286 | * recursion safe and not dynamic and the arch supports passing ops, |
287 | * then have the mcount trampoline call the function directly. | |
cdbe61bf | 288 | */ |
f7aad4e1 | 289 | } else if (ftrace_ops_list->next == &ftrace_list_end) { |
00ccbf2f | 290 | func = ftrace_ops_get_list_func(ftrace_ops_list); |
f7aad4e1 | 291 | |
2f5f6ad9 SR |
292 | } else { |
293 | /* Just use the default ftrace_ops */ | |
405e1d83 | 294 | set_function_trace_op = &ftrace_list_end; |
b848914c | 295 | func = ftrace_ops_list_func; |
2f5f6ad9 | 296 | } |
2b499381 | 297 | |
5f8bf2d2 SRRH |
298 | update_function_graph_func(); |
299 | ||
405e1d83 SRRH |
300 | /* If there's no change, then do nothing more here */ |
301 | if (ftrace_trace_function == func) | |
302 | return; | |
303 | ||
304 | /* | |
305 | * If we are using the list function, it doesn't care | |
306 | * about the function_trace_ops. | |
307 | */ | |
308 | if (func == ftrace_ops_list_func) { | |
309 | ftrace_trace_function = func; | |
310 | /* | |
311 | * Don't even bother setting function_trace_ops, | |
312 | * it would be racy to do so anyway. | |
313 | */ | |
314 | return; | |
315 | } | |
316 | ||
317 | #ifndef CONFIG_DYNAMIC_FTRACE | |
318 | /* | |
319 | * For static tracing, we need to be a bit more careful. | |
320 | * The function change takes affect immediately. Thus, | |
321 | * we need to coorditate the setting of the function_trace_ops | |
322 | * with the setting of the ftrace_trace_function. | |
323 | * | |
324 | * Set the function to the list ops, which will call the | |
325 | * function we want, albeit indirectly, but it handles the | |
326 | * ftrace_ops and doesn't depend on function_trace_op. | |
327 | */ | |
328 | ftrace_trace_function = ftrace_ops_list_func; | |
329 | /* | |
330 | * Make sure all CPUs see this. Yes this is slow, but static | |
331 | * tracing is slow and nasty to have enabled. | |
332 | */ | |
333 | schedule_on_each_cpu(ftrace_sync); | |
334 | /* Now all cpus are using the list ops. */ | |
335 | function_trace_op = set_function_trace_op; | |
336 | /* Make sure the function_trace_op is visible on all CPUs */ | |
337 | smp_wmb(); | |
338 | /* Nasty way to force a rmb on all cpus */ | |
339 | smp_call_function(ftrace_sync_ipi, NULL, 1); | |
340 | /* OK, we are all set to update the ftrace_trace_function now! */ | |
341 | #endif /* !CONFIG_DYNAMIC_FTRACE */ | |
342 | ||
491d0dcf | 343 | ftrace_trace_function = func; |
491d0dcf SR |
344 | } |
345 | ||
7eea4fce JW |
346 | int using_ftrace_ops_list_func(void) |
347 | { | |
348 | return ftrace_trace_function == ftrace_ops_list_func; | |
349 | } | |
350 | ||
2b499381 | 351 | static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
3d083395 | 352 | { |
2b499381 | 353 | ops->next = *list; |
16444a8a | 354 | /* |
b848914c | 355 | * We are entering ops into the list but another |
16444a8a ACM |
356 | * CPU might be walking that list. We need to make sure |
357 | * the ops->next pointer is valid before another CPU sees | |
b848914c | 358 | * the ops pointer included into the list. |
16444a8a | 359 | */ |
2b499381 | 360 | rcu_assign_pointer(*list, ops); |
16444a8a ACM |
361 | } |
362 | ||
2b499381 | 363 | static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
16444a8a | 364 | { |
16444a8a | 365 | struct ftrace_ops **p; |
16444a8a ACM |
366 | |
367 | /* | |
3d083395 SR |
368 | * If we are removing the last function, then simply point |
369 | * to the ftrace_stub. | |
16444a8a | 370 | */ |
2b499381 SR |
371 | if (*list == ops && ops->next == &ftrace_list_end) { |
372 | *list = &ftrace_list_end; | |
e6ea44e9 | 373 | return 0; |
16444a8a ACM |
374 | } |
375 | ||
2b499381 | 376 | for (p = list; *p != &ftrace_list_end; p = &(*p)->next) |
16444a8a ACM |
377 | if (*p == ops) |
378 | break; | |
379 | ||
e6ea44e9 SR |
380 | if (*p != ops) |
381 | return -1; | |
16444a8a ACM |
382 | |
383 | *p = (*p)->next; | |
2b499381 SR |
384 | return 0; |
385 | } | |
16444a8a | 386 | |
f3bea491 SRRH |
387 | static void ftrace_update_trampoline(struct ftrace_ops *ops); |
388 | ||
2b499381 SR |
389 | static int __register_ftrace_function(struct ftrace_ops *ops) |
390 | { | |
591dffda SRRH |
391 | if (ops->flags & FTRACE_OPS_FL_DELETED) |
392 | return -EINVAL; | |
393 | ||
b848914c SR |
394 | if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED)) |
395 | return -EBUSY; | |
396 | ||
06aeaaea | 397 | #ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
08f6fba5 SR |
398 | /* |
399 | * If the ftrace_ops specifies SAVE_REGS, then it only can be used | |
400 | * if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set. | |
401 | * Setting SAVE_REGS_IF_SUPPORTED makes SAVE_REGS irrelevant. | |
402 | */ | |
403 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS && | |
404 | !(ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)) | |
405 | return -EINVAL; | |
406 | ||
407 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED) | |
408 | ops->flags |= FTRACE_OPS_FL_SAVE_REGS; | |
409 | #endif | |
410 | ||
cdbe61bf SR |
411 | if (!core_kernel_data((unsigned long)ops)) |
412 | ops->flags |= FTRACE_OPS_FL_DYNAMIC; | |
413 | ||
ba27f2bc SRRH |
414 | if (ops->flags & FTRACE_OPS_FL_PER_CPU) { |
415 | if (per_cpu_ops_alloc(ops)) | |
e248491a | 416 | return -ENOMEM; |
ba27f2bc SRRH |
417 | } |
418 | ||
419 | add_ftrace_ops(&ftrace_ops_list, ops); | |
b848914c | 420 | |
e3eea140 SRRH |
421 | /* Always save the function, and reset at unregistering */ |
422 | ops->saved_func = ops->func; | |
423 | ||
345ddcc8 | 424 | if (ftrace_pids_enabled(ops)) |
e3eea140 SRRH |
425 | ops->func = ftrace_pid_func; |
426 | ||
f3bea491 SRRH |
427 | ftrace_update_trampoline(ops); |
428 | ||
2b499381 SR |
429 | if (ftrace_enabled) |
430 | update_ftrace_function(); | |
431 | ||
432 | return 0; | |
433 | } | |
434 | ||
435 | static int __unregister_ftrace_function(struct ftrace_ops *ops) | |
436 | { | |
437 | int ret; | |
438 | ||
b848914c SR |
439 | if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) |
440 | return -EBUSY; | |
441 | ||
ba27f2bc | 442 | ret = remove_ftrace_ops(&ftrace_ops_list, ops); |
b848914c | 443 | |
2b499381 SR |
444 | if (ret < 0) |
445 | return ret; | |
b848914c | 446 | |
491d0dcf SR |
447 | if (ftrace_enabled) |
448 | update_ftrace_function(); | |
16444a8a | 449 | |
e3eea140 SRRH |
450 | ops->func = ops->saved_func; |
451 | ||
e6ea44e9 | 452 | return 0; |
3d083395 SR |
453 | } |
454 | ||
df4fc315 SR |
455 | static void ftrace_update_pid_func(void) |
456 | { | |
e3eea140 SRRH |
457 | struct ftrace_ops *op; |
458 | ||
491d0dcf | 459 | /* Only do something if we are tracing something */ |
df4fc315 | 460 | if (ftrace_trace_function == ftrace_stub) |
10dd3ebe | 461 | return; |
df4fc315 | 462 | |
e3eea140 SRRH |
463 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
464 | if (op->flags & FTRACE_OPS_FL_PID) { | |
345ddcc8 SRRH |
465 | op->func = ftrace_pids_enabled(op) ? |
466 | ftrace_pid_func : op->saved_func; | |
e3eea140 SRRH |
467 | ftrace_update_trampoline(op); |
468 | } | |
469 | } while_for_each_ftrace_op(op); | |
470 | ||
491d0dcf | 471 | update_ftrace_function(); |
df4fc315 SR |
472 | } |
473 | ||
493762fc SR |
474 | #ifdef CONFIG_FUNCTION_PROFILER |
475 | struct ftrace_profile { | |
476 | struct hlist_node node; | |
477 | unsigned long ip; | |
478 | unsigned long counter; | |
0706f1c4 SR |
479 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
480 | unsigned long long time; | |
e330b3bc | 481 | unsigned long long time_squared; |
0706f1c4 | 482 | #endif |
8fc0c701 SR |
483 | }; |
484 | ||
493762fc SR |
485 | struct ftrace_profile_page { |
486 | struct ftrace_profile_page *next; | |
487 | unsigned long index; | |
488 | struct ftrace_profile records[]; | |
d61f82d0 SR |
489 | }; |
490 | ||
cafb168a SR |
491 | struct ftrace_profile_stat { |
492 | atomic_t disabled; | |
493 | struct hlist_head *hash; | |
494 | struct ftrace_profile_page *pages; | |
495 | struct ftrace_profile_page *start; | |
496 | struct tracer_stat stat; | |
497 | }; | |
498 | ||
493762fc SR |
499 | #define PROFILE_RECORDS_SIZE \ |
500 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | |
5072c59f | 501 | |
493762fc SR |
502 | #define PROFILES_PER_PAGE \ |
503 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | |
3d083395 | 504 | |
fb9fb015 SR |
505 | static int ftrace_profile_enabled __read_mostly; |
506 | ||
507 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ | |
bac429f0 SR |
508 | static DEFINE_MUTEX(ftrace_profile_lock); |
509 | ||
cafb168a | 510 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); |
493762fc | 511 | |
20079ebe NK |
512 | #define FTRACE_PROFILE_HASH_BITS 10 |
513 | #define FTRACE_PROFILE_HASH_SIZE (1 << FTRACE_PROFILE_HASH_BITS) | |
493762fc | 514 | |
bac429f0 SR |
515 | static void * |
516 | function_stat_next(void *v, int idx) | |
517 | { | |
493762fc SR |
518 | struct ftrace_profile *rec = v; |
519 | struct ftrace_profile_page *pg; | |
bac429f0 | 520 | |
493762fc | 521 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
bac429f0 SR |
522 | |
523 | again: | |
0296e425 LZ |
524 | if (idx != 0) |
525 | rec++; | |
526 | ||
bac429f0 SR |
527 | if ((void *)rec >= (void *)&pg->records[pg->index]) { |
528 | pg = pg->next; | |
529 | if (!pg) | |
530 | return NULL; | |
531 | rec = &pg->records[0]; | |
493762fc SR |
532 | if (!rec->counter) |
533 | goto again; | |
bac429f0 SR |
534 | } |
535 | ||
bac429f0 SR |
536 | return rec; |
537 | } | |
538 | ||
539 | static void *function_stat_start(struct tracer_stat *trace) | |
540 | { | |
cafb168a SR |
541 | struct ftrace_profile_stat *stat = |
542 | container_of(trace, struct ftrace_profile_stat, stat); | |
543 | ||
544 | if (!stat || !stat->start) | |
545 | return NULL; | |
546 | ||
547 | return function_stat_next(&stat->start->records[0], 0); | |
bac429f0 SR |
548 | } |
549 | ||
0706f1c4 SR |
550 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
551 | /* function graph compares on total time */ | |
552 | static int function_stat_cmp(void *p1, void *p2) | |
553 | { | |
554 | struct ftrace_profile *a = p1; | |
555 | struct ftrace_profile *b = p2; | |
556 | ||
557 | if (a->time < b->time) | |
558 | return -1; | |
559 | if (a->time > b->time) | |
560 | return 1; | |
561 | else | |
562 | return 0; | |
563 | } | |
564 | #else | |
565 | /* not function graph compares against hits */ | |
bac429f0 SR |
566 | static int function_stat_cmp(void *p1, void *p2) |
567 | { | |
493762fc SR |
568 | struct ftrace_profile *a = p1; |
569 | struct ftrace_profile *b = p2; | |
bac429f0 SR |
570 | |
571 | if (a->counter < b->counter) | |
572 | return -1; | |
573 | if (a->counter > b->counter) | |
574 | return 1; | |
575 | else | |
576 | return 0; | |
577 | } | |
0706f1c4 | 578 | #endif |
bac429f0 SR |
579 | |
580 | static int function_stat_headers(struct seq_file *m) | |
581 | { | |
0706f1c4 | 582 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
fa6f0cc7 RV |
583 | seq_puts(m, " Function " |
584 | "Hit Time Avg s^2\n" | |
585 | " -------- " | |
586 | "--- ---- --- ---\n"); | |
0706f1c4 | 587 | #else |
fa6f0cc7 RV |
588 | seq_puts(m, " Function Hit\n" |
589 | " -------- ---\n"); | |
0706f1c4 | 590 | #endif |
bac429f0 SR |
591 | return 0; |
592 | } | |
593 | ||
594 | static int function_stat_show(struct seq_file *m, void *v) | |
595 | { | |
493762fc | 596 | struct ftrace_profile *rec = v; |
bac429f0 | 597 | char str[KSYM_SYMBOL_LEN]; |
3aaba20f | 598 | int ret = 0; |
0706f1c4 | 599 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b SR |
600 | static struct trace_seq s; |
601 | unsigned long long avg; | |
e330b3bc | 602 | unsigned long long stddev; |
0706f1c4 | 603 | #endif |
3aaba20f LZ |
604 | mutex_lock(&ftrace_profile_lock); |
605 | ||
606 | /* we raced with function_profile_reset() */ | |
607 | if (unlikely(rec->counter == 0)) { | |
608 | ret = -EBUSY; | |
609 | goto out; | |
610 | } | |
bac429f0 | 611 | |
8e436ca0 UT |
612 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
613 | avg = rec->time; | |
614 | do_div(avg, rec->counter); | |
615 | if (tracing_thresh && (avg < tracing_thresh)) | |
616 | goto out; | |
617 | #endif | |
618 | ||
bac429f0 | 619 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); |
0706f1c4 SR |
620 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); |
621 | ||
622 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
fa6f0cc7 | 623 | seq_puts(m, " "); |
34886c8b | 624 | |
e330b3bc CD |
625 | /* Sample standard deviation (s^2) */ |
626 | if (rec->counter <= 1) | |
627 | stddev = 0; | |
628 | else { | |
52d85d76 JL |
629 | /* |
630 | * Apply Welford's method: | |
631 | * s^2 = 1 / (n * (n-1)) * (n * \Sum (x_i)^2 - (\Sum x_i)^2) | |
632 | */ | |
633 | stddev = rec->counter * rec->time_squared - | |
634 | rec->time * rec->time; | |
635 | ||
e330b3bc CD |
636 | /* |
637 | * Divide only 1000 for ns^2 -> us^2 conversion. | |
638 | * trace_print_graph_duration will divide 1000 again. | |
639 | */ | |
52d85d76 | 640 | do_div(stddev, rec->counter * (rec->counter - 1) * 1000); |
e330b3bc CD |
641 | } |
642 | ||
34886c8b SR |
643 | trace_seq_init(&s); |
644 | trace_print_graph_duration(rec->time, &s); | |
645 | trace_seq_puts(&s, " "); | |
646 | trace_print_graph_duration(avg, &s); | |
e330b3bc CD |
647 | trace_seq_puts(&s, " "); |
648 | trace_print_graph_duration(stddev, &s); | |
0706f1c4 | 649 | trace_print_seq(m, &s); |
0706f1c4 SR |
650 | #endif |
651 | seq_putc(m, '\n'); | |
3aaba20f LZ |
652 | out: |
653 | mutex_unlock(&ftrace_profile_lock); | |
bac429f0 | 654 | |
3aaba20f | 655 | return ret; |
bac429f0 SR |
656 | } |
657 | ||
cafb168a | 658 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) |
bac429f0 | 659 | { |
493762fc | 660 | struct ftrace_profile_page *pg; |
bac429f0 | 661 | |
cafb168a | 662 | pg = stat->pages = stat->start; |
bac429f0 | 663 | |
493762fc SR |
664 | while (pg) { |
665 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | |
666 | pg->index = 0; | |
667 | pg = pg->next; | |
bac429f0 SR |
668 | } |
669 | ||
cafb168a | 670 | memset(stat->hash, 0, |
493762fc SR |
671 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); |
672 | } | |
bac429f0 | 673 | |
cafb168a | 674 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) |
493762fc SR |
675 | { |
676 | struct ftrace_profile_page *pg; | |
318e0a73 SR |
677 | int functions; |
678 | int pages; | |
493762fc | 679 | int i; |
bac429f0 | 680 | |
493762fc | 681 | /* If we already allocated, do nothing */ |
cafb168a | 682 | if (stat->pages) |
493762fc | 683 | return 0; |
bac429f0 | 684 | |
cafb168a SR |
685 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); |
686 | if (!stat->pages) | |
493762fc | 687 | return -ENOMEM; |
bac429f0 | 688 | |
318e0a73 SR |
689 | #ifdef CONFIG_DYNAMIC_FTRACE |
690 | functions = ftrace_update_tot_cnt; | |
691 | #else | |
692 | /* | |
693 | * We do not know the number of functions that exist because | |
694 | * dynamic tracing is what counts them. With past experience | |
695 | * we have around 20K functions. That should be more than enough. | |
696 | * It is highly unlikely we will execute every function in | |
697 | * the kernel. | |
698 | */ | |
699 | functions = 20000; | |
700 | #endif | |
701 | ||
cafb168a | 702 | pg = stat->start = stat->pages; |
bac429f0 | 703 | |
318e0a73 SR |
704 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); |
705 | ||
39e30cd1 | 706 | for (i = 1; i < pages; i++) { |
493762fc | 707 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
493762fc | 708 | if (!pg->next) |
318e0a73 | 709 | goto out_free; |
493762fc SR |
710 | pg = pg->next; |
711 | } | |
712 | ||
713 | return 0; | |
318e0a73 SR |
714 | |
715 | out_free: | |
716 | pg = stat->start; | |
717 | while (pg) { | |
718 | unsigned long tmp = (unsigned long)pg; | |
719 | ||
720 | pg = pg->next; | |
721 | free_page(tmp); | |
722 | } | |
723 | ||
318e0a73 SR |
724 | stat->pages = NULL; |
725 | stat->start = NULL; | |
726 | ||
727 | return -ENOMEM; | |
bac429f0 SR |
728 | } |
729 | ||
cafb168a | 730 | static int ftrace_profile_init_cpu(int cpu) |
bac429f0 | 731 | { |
cafb168a | 732 | struct ftrace_profile_stat *stat; |
493762fc | 733 | int size; |
bac429f0 | 734 | |
cafb168a SR |
735 | stat = &per_cpu(ftrace_profile_stats, cpu); |
736 | ||
737 | if (stat->hash) { | |
493762fc | 738 | /* If the profile is already created, simply reset it */ |
cafb168a | 739 | ftrace_profile_reset(stat); |
493762fc SR |
740 | return 0; |
741 | } | |
bac429f0 | 742 | |
493762fc SR |
743 | /* |
744 | * We are profiling all functions, but usually only a few thousand | |
745 | * functions are hit. We'll make a hash of 1024 items. | |
746 | */ | |
747 | size = FTRACE_PROFILE_HASH_SIZE; | |
bac429f0 | 748 | |
cafb168a | 749 | stat->hash = kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL); |
493762fc | 750 | |
cafb168a | 751 | if (!stat->hash) |
493762fc SR |
752 | return -ENOMEM; |
753 | ||
318e0a73 | 754 | /* Preallocate the function profiling pages */ |
cafb168a SR |
755 | if (ftrace_profile_pages_init(stat) < 0) { |
756 | kfree(stat->hash); | |
757 | stat->hash = NULL; | |
493762fc SR |
758 | return -ENOMEM; |
759 | } | |
760 | ||
761 | return 0; | |
bac429f0 SR |
762 | } |
763 | ||
cafb168a SR |
764 | static int ftrace_profile_init(void) |
765 | { | |
766 | int cpu; | |
767 | int ret = 0; | |
768 | ||
c4602c1c | 769 | for_each_possible_cpu(cpu) { |
cafb168a SR |
770 | ret = ftrace_profile_init_cpu(cpu); |
771 | if (ret) | |
772 | break; | |
773 | } | |
774 | ||
775 | return ret; | |
776 | } | |
777 | ||
493762fc | 778 | /* interrupts must be disabled */ |
cafb168a SR |
779 | static struct ftrace_profile * |
780 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) | |
bac429f0 | 781 | { |
493762fc | 782 | struct ftrace_profile *rec; |
bac429f0 | 783 | struct hlist_head *hhd; |
bac429f0 SR |
784 | unsigned long key; |
785 | ||
20079ebe | 786 | key = hash_long(ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 787 | hhd = &stat->hash[key]; |
bac429f0 SR |
788 | |
789 | if (hlist_empty(hhd)) | |
790 | return NULL; | |
791 | ||
1bb539ca | 792 | hlist_for_each_entry_rcu_notrace(rec, hhd, node) { |
bac429f0 | 793 | if (rec->ip == ip) |
493762fc SR |
794 | return rec; |
795 | } | |
796 | ||
797 | return NULL; | |
798 | } | |
799 | ||
cafb168a SR |
800 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, |
801 | struct ftrace_profile *rec) | |
493762fc SR |
802 | { |
803 | unsigned long key; | |
804 | ||
20079ebe | 805 | key = hash_long(rec->ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 806 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); |
493762fc SR |
807 | } |
808 | ||
318e0a73 SR |
809 | /* |
810 | * The memory is already allocated, this simply finds a new record to use. | |
811 | */ | |
493762fc | 812 | static struct ftrace_profile * |
318e0a73 | 813 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) |
493762fc SR |
814 | { |
815 | struct ftrace_profile *rec = NULL; | |
816 | ||
318e0a73 | 817 | /* prevent recursion (from NMIs) */ |
cafb168a | 818 | if (atomic_inc_return(&stat->disabled) != 1) |
493762fc SR |
819 | goto out; |
820 | ||
493762fc | 821 | /* |
318e0a73 SR |
822 | * Try to find the function again since an NMI |
823 | * could have added it | |
493762fc | 824 | */ |
cafb168a | 825 | rec = ftrace_find_profiled_func(stat, ip); |
493762fc | 826 | if (rec) |
cafb168a | 827 | goto out; |
493762fc | 828 | |
cafb168a SR |
829 | if (stat->pages->index == PROFILES_PER_PAGE) { |
830 | if (!stat->pages->next) | |
831 | goto out; | |
832 | stat->pages = stat->pages->next; | |
bac429f0 | 833 | } |
493762fc | 834 | |
cafb168a | 835 | rec = &stat->pages->records[stat->pages->index++]; |
493762fc | 836 | rec->ip = ip; |
cafb168a | 837 | ftrace_add_profile(stat, rec); |
493762fc | 838 | |
bac429f0 | 839 | out: |
cafb168a | 840 | atomic_dec(&stat->disabled); |
bac429f0 SR |
841 | |
842 | return rec; | |
843 | } | |
844 | ||
845 | static void | |
2f5f6ad9 | 846 | function_profile_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 847 | struct ftrace_ops *ops, struct pt_regs *regs) |
bac429f0 | 848 | { |
cafb168a | 849 | struct ftrace_profile_stat *stat; |
493762fc | 850 | struct ftrace_profile *rec; |
bac429f0 SR |
851 | unsigned long flags; |
852 | ||
853 | if (!ftrace_profile_enabled) | |
854 | return; | |
855 | ||
856 | local_irq_save(flags); | |
cafb168a | 857 | |
bdffd893 | 858 | stat = this_cpu_ptr(&ftrace_profile_stats); |
0f6ce3de | 859 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
860 | goto out; |
861 | ||
862 | rec = ftrace_find_profiled_func(stat, ip); | |
493762fc | 863 | if (!rec) { |
318e0a73 | 864 | rec = ftrace_profile_alloc(stat, ip); |
493762fc SR |
865 | if (!rec) |
866 | goto out; | |
867 | } | |
bac429f0 SR |
868 | |
869 | rec->counter++; | |
870 | out: | |
871 | local_irq_restore(flags); | |
872 | } | |
873 | ||
0706f1c4 SR |
874 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
875 | static int profile_graph_entry(struct ftrace_graph_ent *trace) | |
876 | { | |
8861dd30 NK |
877 | int index = trace->depth; |
878 | ||
a1e2e31d | 879 | function_profile_call(trace->func, 0, NULL, NULL); |
8861dd30 NK |
880 | |
881 | if (index >= 0 && index < FTRACE_RETFUNC_DEPTH) | |
882 | current->ret_stack[index].subtime = 0; | |
883 | ||
0706f1c4 SR |
884 | return 1; |
885 | } | |
886 | ||
887 | static void profile_graph_return(struct ftrace_graph_ret *trace) | |
888 | { | |
cafb168a | 889 | struct ftrace_profile_stat *stat; |
a2a16d6a | 890 | unsigned long long calltime; |
0706f1c4 | 891 | struct ftrace_profile *rec; |
cafb168a | 892 | unsigned long flags; |
0706f1c4 SR |
893 | |
894 | local_irq_save(flags); | |
bdffd893 | 895 | stat = this_cpu_ptr(&ftrace_profile_stats); |
0f6ce3de | 896 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
897 | goto out; |
898 | ||
37e44bc5 SR |
899 | /* If the calltime was zero'd ignore it */ |
900 | if (!trace->calltime) | |
901 | goto out; | |
902 | ||
a2a16d6a SR |
903 | calltime = trace->rettime - trace->calltime; |
904 | ||
55577204 | 905 | if (!fgraph_graph_time) { |
a2a16d6a SR |
906 | int index; |
907 | ||
908 | index = trace->depth; | |
909 | ||
910 | /* Append this call time to the parent time to subtract */ | |
911 | if (index) | |
912 | current->ret_stack[index - 1].subtime += calltime; | |
913 | ||
914 | if (current->ret_stack[index].subtime < calltime) | |
915 | calltime -= current->ret_stack[index].subtime; | |
916 | else | |
917 | calltime = 0; | |
918 | } | |
919 | ||
cafb168a | 920 | rec = ftrace_find_profiled_func(stat, trace->func); |
e330b3bc | 921 | if (rec) { |
a2a16d6a | 922 | rec->time += calltime; |
e330b3bc CD |
923 | rec->time_squared += calltime * calltime; |
924 | } | |
a2a16d6a | 925 | |
cafb168a | 926 | out: |
0706f1c4 SR |
927 | local_irq_restore(flags); |
928 | } | |
929 | ||
930 | static int register_ftrace_profiler(void) | |
931 | { | |
932 | return register_ftrace_graph(&profile_graph_return, | |
933 | &profile_graph_entry); | |
934 | } | |
935 | ||
936 | static void unregister_ftrace_profiler(void) | |
937 | { | |
938 | unregister_ftrace_graph(); | |
939 | } | |
940 | #else | |
bd38c0e6 | 941 | static struct ftrace_ops ftrace_profile_ops __read_mostly = { |
fb9fb015 | 942 | .func = function_profile_call, |
f04f24fb | 943 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, |
33b7f99c | 944 | INIT_OPS_HASH(ftrace_profile_ops) |
bac429f0 SR |
945 | }; |
946 | ||
0706f1c4 SR |
947 | static int register_ftrace_profiler(void) |
948 | { | |
949 | return register_ftrace_function(&ftrace_profile_ops); | |
950 | } | |
951 | ||
952 | static void unregister_ftrace_profiler(void) | |
953 | { | |
954 | unregister_ftrace_function(&ftrace_profile_ops); | |
955 | } | |
956 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
957 | ||
bac429f0 SR |
958 | static ssize_t |
959 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | |
960 | size_t cnt, loff_t *ppos) | |
961 | { | |
962 | unsigned long val; | |
bac429f0 SR |
963 | int ret; |
964 | ||
22fe9b54 PH |
965 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
966 | if (ret) | |
bac429f0 SR |
967 | return ret; |
968 | ||
969 | val = !!val; | |
970 | ||
971 | mutex_lock(&ftrace_profile_lock); | |
972 | if (ftrace_profile_enabled ^ val) { | |
973 | if (val) { | |
493762fc SR |
974 | ret = ftrace_profile_init(); |
975 | if (ret < 0) { | |
976 | cnt = ret; | |
977 | goto out; | |
978 | } | |
979 | ||
0706f1c4 SR |
980 | ret = register_ftrace_profiler(); |
981 | if (ret < 0) { | |
982 | cnt = ret; | |
983 | goto out; | |
984 | } | |
bac429f0 SR |
985 | ftrace_profile_enabled = 1; |
986 | } else { | |
987 | ftrace_profile_enabled = 0; | |
0f6ce3de SR |
988 | /* |
989 | * unregister_ftrace_profiler calls stop_machine | |
990 | * so this acts like an synchronize_sched. | |
991 | */ | |
0706f1c4 | 992 | unregister_ftrace_profiler(); |
bac429f0 SR |
993 | } |
994 | } | |
493762fc | 995 | out: |
bac429f0 SR |
996 | mutex_unlock(&ftrace_profile_lock); |
997 | ||
cf8517cf | 998 | *ppos += cnt; |
bac429f0 SR |
999 | |
1000 | return cnt; | |
1001 | } | |
1002 | ||
493762fc SR |
1003 | static ssize_t |
1004 | ftrace_profile_read(struct file *filp, char __user *ubuf, | |
1005 | size_t cnt, loff_t *ppos) | |
1006 | { | |
fb9fb015 | 1007 | char buf[64]; /* big enough to hold a number */ |
493762fc SR |
1008 | int r; |
1009 | ||
1010 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | |
1011 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
1012 | } | |
1013 | ||
bac429f0 SR |
1014 | static const struct file_operations ftrace_profile_fops = { |
1015 | .open = tracing_open_generic, | |
1016 | .read = ftrace_profile_read, | |
1017 | .write = ftrace_profile_write, | |
6038f373 | 1018 | .llseek = default_llseek, |
bac429f0 SR |
1019 | }; |
1020 | ||
cafb168a SR |
1021 | /* used to initialize the real stat files */ |
1022 | static struct tracer_stat function_stats __initdata = { | |
fb9fb015 SR |
1023 | .name = "functions", |
1024 | .stat_start = function_stat_start, | |
1025 | .stat_next = function_stat_next, | |
1026 | .stat_cmp = function_stat_cmp, | |
1027 | .stat_headers = function_stat_headers, | |
1028 | .stat_show = function_stat_show | |
cafb168a SR |
1029 | }; |
1030 | ||
8434dc93 | 1031 | static __init void ftrace_profile_tracefs(struct dentry *d_tracer) |
bac429f0 | 1032 | { |
cafb168a | 1033 | struct ftrace_profile_stat *stat; |
bac429f0 | 1034 | struct dentry *entry; |
cafb168a | 1035 | char *name; |
bac429f0 | 1036 | int ret; |
cafb168a SR |
1037 | int cpu; |
1038 | ||
1039 | for_each_possible_cpu(cpu) { | |
1040 | stat = &per_cpu(ftrace_profile_stats, cpu); | |
1041 | ||
6363c6b5 | 1042 | name = kasprintf(GFP_KERNEL, "function%d", cpu); |
cafb168a SR |
1043 | if (!name) { |
1044 | /* | |
1045 | * The files created are permanent, if something happens | |
1046 | * we still do not free memory. | |
1047 | */ | |
cafb168a SR |
1048 | WARN(1, |
1049 | "Could not allocate stat file for cpu %d\n", | |
1050 | cpu); | |
1051 | return; | |
1052 | } | |
1053 | stat->stat = function_stats; | |
cafb168a SR |
1054 | stat->stat.name = name; |
1055 | ret = register_stat_tracer(&stat->stat); | |
1056 | if (ret) { | |
1057 | WARN(1, | |
1058 | "Could not register function stat for cpu %d\n", | |
1059 | cpu); | |
1060 | kfree(name); | |
1061 | return; | |
1062 | } | |
bac429f0 SR |
1063 | } |
1064 | ||
8434dc93 | 1065 | entry = tracefs_create_file("function_profile_enabled", 0644, |
bac429f0 SR |
1066 | d_tracer, NULL, &ftrace_profile_fops); |
1067 | if (!entry) | |
a395d6a7 | 1068 | pr_warn("Could not create tracefs 'function_profile_enabled' entry\n"); |
bac429f0 SR |
1069 | } |
1070 | ||
bac429f0 | 1071 | #else /* CONFIG_FUNCTION_PROFILER */ |
8434dc93 | 1072 | static __init void ftrace_profile_tracefs(struct dentry *d_tracer) |
bac429f0 SR |
1073 | { |
1074 | } | |
bac429f0 SR |
1075 | #endif /* CONFIG_FUNCTION_PROFILER */ |
1076 | ||
493762fc SR |
1077 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; |
1078 | ||
1619dc3f PA |
1079 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
1080 | static int ftrace_graph_active; | |
1081 | #else | |
1082 | # define ftrace_graph_active 0 | |
1083 | #endif | |
1084 | ||
493762fc SR |
1085 | #ifdef CONFIG_DYNAMIC_FTRACE |
1086 | ||
79922b80 SRRH |
1087 | static struct ftrace_ops *removed_ops; |
1088 | ||
e1effa01 SRRH |
1089 | /* |
1090 | * Set when doing a global update, like enabling all recs or disabling them. | |
1091 | * It is not set when just updating a single ftrace_ops. | |
1092 | */ | |
1093 | static bool update_all_ops; | |
1094 | ||
493762fc SR |
1095 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD |
1096 | # error Dynamic ftrace depends on MCOUNT_RECORD | |
1097 | #endif | |
1098 | ||
b448c4e3 SR |
1099 | struct ftrace_func_entry { |
1100 | struct hlist_node hlist; | |
1101 | unsigned long ip; | |
1102 | }; | |
1103 | ||
7b60f3d8 SRV |
1104 | struct ftrace_func_probe { |
1105 | struct ftrace_probe_ops *probe_ops; | |
1106 | struct ftrace_ops ops; | |
1107 | struct trace_array *tr; | |
1108 | struct list_head list; | |
6e444319 | 1109 | void *data; |
7b60f3d8 SRV |
1110 | int ref; |
1111 | }; | |
1112 | ||
33dc9b12 SR |
1113 | /* |
1114 | * We make these constant because no one should touch them, | |
1115 | * but they are used as the default "empty hash", to avoid allocating | |
1116 | * it all the time. These are in a read only section such that if | |
1117 | * anyone does try to modify it, it will cause an exception. | |
1118 | */ | |
1119 | static const struct hlist_head empty_buckets[1]; | |
1120 | static const struct ftrace_hash empty_hash = { | |
1121 | .buckets = (struct hlist_head *)empty_buckets, | |
1cf41dd7 | 1122 | }; |
33dc9b12 | 1123 | #define EMPTY_HASH ((struct ftrace_hash *)&empty_hash) |
493762fc | 1124 | |
2b499381 | 1125 | static struct ftrace_ops global_ops = { |
33b7f99c SRRH |
1126 | .func = ftrace_stub, |
1127 | .local_hash.notrace_hash = EMPTY_HASH, | |
1128 | .local_hash.filter_hash = EMPTY_HASH, | |
1129 | INIT_OPS_HASH(global_ops) | |
1130 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | | |
e3eea140 SRRH |
1131 | FTRACE_OPS_FL_INITIALIZED | |
1132 | FTRACE_OPS_FL_PID, | |
f45948e8 SR |
1133 | }; |
1134 | ||
aec0be2d SRRH |
1135 | /* |
1136 | * This is used by __kernel_text_address() to return true if the | |
0af26492 | 1137 | * address is on a dynamically allocated trampoline that would |
aec0be2d SRRH |
1138 | * not return true for either core_kernel_text() or |
1139 | * is_module_text_address(). | |
1140 | */ | |
1141 | bool is_ftrace_trampoline(unsigned long addr) | |
1142 | { | |
1143 | struct ftrace_ops *op; | |
1144 | bool ret = false; | |
1145 | ||
1146 | /* | |
1147 | * Some of the ops may be dynamically allocated, | |
1148 | * they are freed after a synchronize_sched(). | |
1149 | */ | |
1150 | preempt_disable_notrace(); | |
1151 | ||
1152 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
1153 | /* | |
1154 | * This is to check for dynamically allocated trampolines. | |
1155 | * Trampolines that are in kernel text will have | |
1156 | * core_kernel_text() return true. | |
1157 | */ | |
1158 | if (op->trampoline && op->trampoline_size) | |
1159 | if (addr >= op->trampoline && | |
1160 | addr < op->trampoline + op->trampoline_size) { | |
1161 | ret = true; | |
1162 | goto out; | |
1163 | } | |
1164 | } while_for_each_ftrace_op(op); | |
1165 | ||
1166 | out: | |
1167 | preempt_enable_notrace(); | |
1168 | ||
1169 | return ret; | |
1170 | } | |
1171 | ||
493762fc SR |
1172 | struct ftrace_page { |
1173 | struct ftrace_page *next; | |
a7900875 | 1174 | struct dyn_ftrace *records; |
493762fc | 1175 | int index; |
a7900875 | 1176 | int size; |
493762fc SR |
1177 | }; |
1178 | ||
a7900875 SR |
1179 | #define ENTRY_SIZE sizeof(struct dyn_ftrace) |
1180 | #define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE) | |
493762fc SR |
1181 | |
1182 | /* estimate from running different kernels */ | |
1183 | #define NR_TO_INIT 10000 | |
1184 | ||
1185 | static struct ftrace_page *ftrace_pages_start; | |
1186 | static struct ftrace_page *ftrace_pages; | |
1187 | ||
2b0cce0e SRV |
1188 | static __always_inline unsigned long |
1189 | ftrace_hash_key(struct ftrace_hash *hash, unsigned long ip) | |
1190 | { | |
1191 | if (hash->size_bits > 0) | |
1192 | return hash_long(ip, hash->size_bits); | |
1193 | ||
1194 | return 0; | |
1195 | } | |
1196 | ||
2b2c279c SRV |
1197 | /* Only use this function if ftrace_hash_empty() has already been tested */ |
1198 | static __always_inline struct ftrace_func_entry * | |
1199 | __ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
b448c4e3 SR |
1200 | { |
1201 | unsigned long key; | |
1202 | struct ftrace_func_entry *entry; | |
1203 | struct hlist_head *hhd; | |
b448c4e3 | 1204 | |
2b0cce0e | 1205 | key = ftrace_hash_key(hash, ip); |
b448c4e3 SR |
1206 | hhd = &hash->buckets[key]; |
1207 | ||
1bb539ca | 1208 | hlist_for_each_entry_rcu_notrace(entry, hhd, hlist) { |
b448c4e3 SR |
1209 | if (entry->ip == ip) |
1210 | return entry; | |
1211 | } | |
1212 | return NULL; | |
1213 | } | |
1214 | ||
2b2c279c SRV |
1215 | /** |
1216 | * ftrace_lookup_ip - Test to see if an ip exists in an ftrace_hash | |
1217 | * @hash: The hash to look at | |
1218 | * @ip: The instruction pointer to test | |
1219 | * | |
1220 | * Search a given @hash to see if a given instruction pointer (@ip) | |
1221 | * exists in it. | |
1222 | * | |
1223 | * Returns the entry that holds the @ip if found. NULL otherwise. | |
1224 | */ | |
1225 | struct ftrace_func_entry * | |
1226 | ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
1227 | { | |
1228 | if (ftrace_hash_empty(hash)) | |
1229 | return NULL; | |
1230 | ||
1231 | return __ftrace_lookup_ip(hash, ip); | |
1232 | } | |
1233 | ||
33dc9b12 SR |
1234 | static void __add_hash_entry(struct ftrace_hash *hash, |
1235 | struct ftrace_func_entry *entry) | |
b448c4e3 | 1236 | { |
b448c4e3 SR |
1237 | struct hlist_head *hhd; |
1238 | unsigned long key; | |
1239 | ||
2b0cce0e | 1240 | key = ftrace_hash_key(hash, entry->ip); |
b448c4e3 SR |
1241 | hhd = &hash->buckets[key]; |
1242 | hlist_add_head(&entry->hlist, hhd); | |
1243 | hash->count++; | |
33dc9b12 SR |
1244 | } |
1245 | ||
1246 | static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) | |
1247 | { | |
1248 | struct ftrace_func_entry *entry; | |
1249 | ||
1250 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
1251 | if (!entry) | |
1252 | return -ENOMEM; | |
1253 | ||
1254 | entry->ip = ip; | |
1255 | __add_hash_entry(hash, entry); | |
b448c4e3 SR |
1256 | |
1257 | return 0; | |
1258 | } | |
1259 | ||
1260 | static void | |
33dc9b12 | 1261 | free_hash_entry(struct ftrace_hash *hash, |
b448c4e3 SR |
1262 | struct ftrace_func_entry *entry) |
1263 | { | |
1264 | hlist_del(&entry->hlist); | |
1265 | kfree(entry); | |
1266 | hash->count--; | |
1267 | } | |
1268 | ||
33dc9b12 SR |
1269 | static void |
1270 | remove_hash_entry(struct ftrace_hash *hash, | |
1271 | struct ftrace_func_entry *entry) | |
1272 | { | |
eee8ded1 | 1273 | hlist_del_rcu(&entry->hlist); |
33dc9b12 SR |
1274 | hash->count--; |
1275 | } | |
1276 | ||
b448c4e3 SR |
1277 | static void ftrace_hash_clear(struct ftrace_hash *hash) |
1278 | { | |
1279 | struct hlist_head *hhd; | |
b67bfe0d | 1280 | struct hlist_node *tn; |
b448c4e3 SR |
1281 | struct ftrace_func_entry *entry; |
1282 | int size = 1 << hash->size_bits; | |
1283 | int i; | |
1284 | ||
33dc9b12 SR |
1285 | if (!hash->count) |
1286 | return; | |
1287 | ||
b448c4e3 SR |
1288 | for (i = 0; i < size; i++) { |
1289 | hhd = &hash->buckets[i]; | |
b67bfe0d | 1290 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) |
33dc9b12 | 1291 | free_hash_entry(hash, entry); |
b448c4e3 SR |
1292 | } |
1293 | FTRACE_WARN_ON(hash->count); | |
1294 | } | |
1295 | ||
33dc9b12 SR |
1296 | static void free_ftrace_hash(struct ftrace_hash *hash) |
1297 | { | |
1298 | if (!hash || hash == EMPTY_HASH) | |
1299 | return; | |
1300 | ftrace_hash_clear(hash); | |
1301 | kfree(hash->buckets); | |
1302 | kfree(hash); | |
1303 | } | |
1304 | ||
07fd5515 SR |
1305 | static void __free_ftrace_hash_rcu(struct rcu_head *rcu) |
1306 | { | |
1307 | struct ftrace_hash *hash; | |
1308 | ||
1309 | hash = container_of(rcu, struct ftrace_hash, rcu); | |
1310 | free_ftrace_hash(hash); | |
1311 | } | |
1312 | ||
1313 | static void free_ftrace_hash_rcu(struct ftrace_hash *hash) | |
1314 | { | |
1315 | if (!hash || hash == EMPTY_HASH) | |
1316 | return; | |
1317 | call_rcu_sched(&hash->rcu, __free_ftrace_hash_rcu); | |
1318 | } | |
1319 | ||
5500fa51 JO |
1320 | void ftrace_free_filter(struct ftrace_ops *ops) |
1321 | { | |
f04f24fb | 1322 | ftrace_ops_init(ops); |
33b7f99c SRRH |
1323 | free_ftrace_hash(ops->func_hash->filter_hash); |
1324 | free_ftrace_hash(ops->func_hash->notrace_hash); | |
5500fa51 JO |
1325 | } |
1326 | ||
33dc9b12 SR |
1327 | static struct ftrace_hash *alloc_ftrace_hash(int size_bits) |
1328 | { | |
1329 | struct ftrace_hash *hash; | |
1330 | int size; | |
1331 | ||
1332 | hash = kzalloc(sizeof(*hash), GFP_KERNEL); | |
1333 | if (!hash) | |
1334 | return NULL; | |
1335 | ||
1336 | size = 1 << size_bits; | |
47b0edcb | 1337 | hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL); |
33dc9b12 SR |
1338 | |
1339 | if (!hash->buckets) { | |
1340 | kfree(hash); | |
1341 | return NULL; | |
1342 | } | |
1343 | ||
1344 | hash->size_bits = size_bits; | |
1345 | ||
1346 | return hash; | |
1347 | } | |
1348 | ||
1349 | static struct ftrace_hash * | |
1350 | alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) | |
1351 | { | |
1352 | struct ftrace_func_entry *entry; | |
1353 | struct ftrace_hash *new_hash; | |
33dc9b12 SR |
1354 | int size; |
1355 | int ret; | |
1356 | int i; | |
1357 | ||
1358 | new_hash = alloc_ftrace_hash(size_bits); | |
1359 | if (!new_hash) | |
1360 | return NULL; | |
1361 | ||
1362 | /* Empty hash? */ | |
06a51d93 | 1363 | if (ftrace_hash_empty(hash)) |
33dc9b12 SR |
1364 | return new_hash; |
1365 | ||
1366 | size = 1 << hash->size_bits; | |
1367 | for (i = 0; i < size; i++) { | |
b67bfe0d | 1368 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { |
33dc9b12 SR |
1369 | ret = add_hash_entry(new_hash, entry->ip); |
1370 | if (ret < 0) | |
1371 | goto free_hash; | |
1372 | } | |
1373 | } | |
1374 | ||
1375 | FTRACE_WARN_ON(new_hash->count != hash->count); | |
1376 | ||
1377 | return new_hash; | |
1378 | ||
1379 | free_hash: | |
1380 | free_ftrace_hash(new_hash); | |
1381 | return NULL; | |
1382 | } | |
1383 | ||
41fb61c2 | 1384 | static void |
84261912 | 1385 | ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, int filter_hash); |
41fb61c2 | 1386 | static void |
84261912 | 1387 | ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, int filter_hash); |
41fb61c2 | 1388 | |
f8b8be8a MH |
1389 | static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops, |
1390 | struct ftrace_hash *new_hash); | |
1391 | ||
3e278c0d NK |
1392 | static struct ftrace_hash * |
1393 | __ftrace_hash_move(struct ftrace_hash *src) | |
33dc9b12 SR |
1394 | { |
1395 | struct ftrace_func_entry *entry; | |
b67bfe0d | 1396 | struct hlist_node *tn; |
33dc9b12 | 1397 | struct hlist_head *hhd; |
07fd5515 | 1398 | struct ftrace_hash *new_hash; |
33dc9b12 SR |
1399 | int size = src->count; |
1400 | int bits = 0; | |
1401 | int i; | |
1402 | ||
1403 | /* | |
3e278c0d | 1404 | * If the new source is empty, just return the empty_hash. |
33dc9b12 | 1405 | */ |
3e278c0d NK |
1406 | if (!src->count) |
1407 | return EMPTY_HASH; | |
33dc9b12 | 1408 | |
33dc9b12 SR |
1409 | /* |
1410 | * Make the hash size about 1/2 the # found | |
1411 | */ | |
1412 | for (size /= 2; size; size >>= 1) | |
1413 | bits++; | |
1414 | ||
1415 | /* Don't allocate too much */ | |
1416 | if (bits > FTRACE_HASH_MAX_BITS) | |
1417 | bits = FTRACE_HASH_MAX_BITS; | |
1418 | ||
07fd5515 SR |
1419 | new_hash = alloc_ftrace_hash(bits); |
1420 | if (!new_hash) | |
3e278c0d | 1421 | return NULL; |
33dc9b12 SR |
1422 | |
1423 | size = 1 << src->size_bits; | |
1424 | for (i = 0; i < size; i++) { | |
1425 | hhd = &src->buckets[i]; | |
b67bfe0d | 1426 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) { |
33dc9b12 | 1427 | remove_hash_entry(src, entry); |
07fd5515 | 1428 | __add_hash_entry(new_hash, entry); |
33dc9b12 SR |
1429 | } |
1430 | } | |
1431 | ||
3e278c0d NK |
1432 | return new_hash; |
1433 | } | |
1434 | ||
1435 | static int | |
1436 | ftrace_hash_move(struct ftrace_ops *ops, int enable, | |
1437 | struct ftrace_hash **dst, struct ftrace_hash *src) | |
1438 | { | |
1439 | struct ftrace_hash *new_hash; | |
1440 | int ret; | |
1441 | ||
1442 | /* Reject setting notrace hash on IPMODIFY ftrace_ops */ | |
1443 | if (ops->flags & FTRACE_OPS_FL_IPMODIFY && !enable) | |
1444 | return -EINVAL; | |
1445 | ||
1446 | new_hash = __ftrace_hash_move(src); | |
1447 | if (!new_hash) | |
1448 | return -ENOMEM; | |
1449 | ||
f8b8be8a MH |
1450 | /* Make sure this can be applied if it is IPMODIFY ftrace_ops */ |
1451 | if (enable) { | |
1452 | /* IPMODIFY should be updated only when filter_hash updating */ | |
1453 | ret = ftrace_hash_ipmodify_update(ops, new_hash); | |
1454 | if (ret < 0) { | |
1455 | free_ftrace_hash(new_hash); | |
1456 | return ret; | |
1457 | } | |
1458 | } | |
1459 | ||
5c27c775 MH |
1460 | /* |
1461 | * Remove the current set, update the hash and add | |
1462 | * them back. | |
1463 | */ | |
84261912 | 1464 | ftrace_hash_rec_disable_modify(ops, enable); |
5c27c775 | 1465 | |
07fd5515 | 1466 | rcu_assign_pointer(*dst, new_hash); |
07fd5515 | 1467 | |
84261912 | 1468 | ftrace_hash_rec_enable_modify(ops, enable); |
41fb61c2 | 1469 | |
5c27c775 | 1470 | return 0; |
33dc9b12 SR |
1471 | } |
1472 | ||
fef5aeee SRRH |
1473 | static bool hash_contains_ip(unsigned long ip, |
1474 | struct ftrace_ops_hash *hash) | |
1475 | { | |
1476 | /* | |
1477 | * The function record is a match if it exists in the filter | |
1478 | * hash and not in the notrace hash. Note, an emty hash is | |
1479 | * considered a match for the filter hash, but an empty | |
1480 | * notrace hash is considered not in the notrace hash. | |
1481 | */ | |
1482 | return (ftrace_hash_empty(hash->filter_hash) || | |
2b2c279c | 1483 | __ftrace_lookup_ip(hash->filter_hash, ip)) && |
fef5aeee | 1484 | (ftrace_hash_empty(hash->notrace_hash) || |
2b2c279c | 1485 | !__ftrace_lookup_ip(hash->notrace_hash, ip)); |
fef5aeee SRRH |
1486 | } |
1487 | ||
b848914c SR |
1488 | /* |
1489 | * Test the hashes for this ops to see if we want to call | |
1490 | * the ops->func or not. | |
1491 | * | |
1492 | * It's a match if the ip is in the ops->filter_hash or | |
1493 | * the filter_hash does not exist or is empty, | |
1494 | * AND | |
1495 | * the ip is not in the ops->notrace_hash. | |
cdbe61bf SR |
1496 | * |
1497 | * This needs to be called with preemption disabled as | |
1498 | * the hashes are freed with call_rcu_sched(). | |
b848914c SR |
1499 | */ |
1500 | static int | |
195a8afc | 1501 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs) |
b848914c | 1502 | { |
fef5aeee | 1503 | struct ftrace_ops_hash hash; |
b848914c SR |
1504 | int ret; |
1505 | ||
195a8afc SRRH |
1506 | #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
1507 | /* | |
1508 | * There's a small race when adding ops that the ftrace handler | |
1509 | * that wants regs, may be called without them. We can not | |
1510 | * allow that handler to be called if regs is NULL. | |
1511 | */ | |
1512 | if (regs == NULL && (ops->flags & FTRACE_OPS_FL_SAVE_REGS)) | |
1513 | return 0; | |
1514 | #endif | |
1515 | ||
fef5aeee SRRH |
1516 | hash.filter_hash = rcu_dereference_raw_notrace(ops->func_hash->filter_hash); |
1517 | hash.notrace_hash = rcu_dereference_raw_notrace(ops->func_hash->notrace_hash); | |
b848914c | 1518 | |
fef5aeee | 1519 | if (hash_contains_ip(ip, &hash)) |
b848914c SR |
1520 | ret = 1; |
1521 | else | |
1522 | ret = 0; | |
b848914c SR |
1523 | |
1524 | return ret; | |
1525 | } | |
1526 | ||
493762fc SR |
1527 | /* |
1528 | * This is a double for. Do not use 'break' to break out of the loop, | |
1529 | * you must use a goto. | |
1530 | */ | |
1531 | #define do_for_each_ftrace_rec(pg, rec) \ | |
1532 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
1533 | int _____i; \ | |
1534 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
1535 | rec = &pg->records[_____i]; | |
1536 | ||
1537 | #define while_for_each_ftrace_rec() \ | |
1538 | } \ | |
1539 | } | |
1540 | ||
5855fead SR |
1541 | |
1542 | static int ftrace_cmp_recs(const void *a, const void *b) | |
1543 | { | |
a650e02a SR |
1544 | const struct dyn_ftrace *key = a; |
1545 | const struct dyn_ftrace *rec = b; | |
5855fead | 1546 | |
a650e02a | 1547 | if (key->flags < rec->ip) |
5855fead | 1548 | return -1; |
a650e02a SR |
1549 | if (key->ip >= rec->ip + MCOUNT_INSN_SIZE) |
1550 | return 1; | |
5855fead SR |
1551 | return 0; |
1552 | } | |
1553 | ||
04cf31a7 ME |
1554 | /** |
1555 | * ftrace_location_range - return the first address of a traced location | |
1556 | * if it touches the given ip range | |
1557 | * @start: start of range to search. | |
1558 | * @end: end of range to search (inclusive). @end points to the last byte | |
1559 | * to check. | |
1560 | * | |
1561 | * Returns rec->ip if the related ftrace location is a least partly within | |
1562 | * the given address range. That is, the first address of the instruction | |
1563 | * that is either a NOP or call to the function tracer. It checks the ftrace | |
1564 | * internal tables to determine if the address belongs or not. | |
1565 | */ | |
1566 | unsigned long ftrace_location_range(unsigned long start, unsigned long end) | |
c88fd863 SR |
1567 | { |
1568 | struct ftrace_page *pg; | |
1569 | struct dyn_ftrace *rec; | |
5855fead | 1570 | struct dyn_ftrace key; |
c88fd863 | 1571 | |
a650e02a SR |
1572 | key.ip = start; |
1573 | key.flags = end; /* overload flags, as it is unsigned long */ | |
5855fead SR |
1574 | |
1575 | for (pg = ftrace_pages_start; pg; pg = pg->next) { | |
a650e02a SR |
1576 | if (end < pg->records[0].ip || |
1577 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) | |
9644302e | 1578 | continue; |
5855fead SR |
1579 | rec = bsearch(&key, pg->records, pg->index, |
1580 | sizeof(struct dyn_ftrace), | |
1581 | ftrace_cmp_recs); | |
1582 | if (rec) | |
f0cf973a | 1583 | return rec->ip; |
5855fead | 1584 | } |
c88fd863 SR |
1585 | |
1586 | return 0; | |
1587 | } | |
1588 | ||
a650e02a SR |
1589 | /** |
1590 | * ftrace_location - return true if the ip giving is a traced location | |
1591 | * @ip: the instruction pointer to check | |
1592 | * | |
f0cf973a | 1593 | * Returns rec->ip if @ip given is a pointer to a ftrace location. |
a650e02a SR |
1594 | * That is, the instruction that is either a NOP or call to |
1595 | * the function tracer. It checks the ftrace internal tables to | |
1596 | * determine if the address belongs or not. | |
1597 | */ | |
f0cf973a | 1598 | unsigned long ftrace_location(unsigned long ip) |
a650e02a SR |
1599 | { |
1600 | return ftrace_location_range(ip, ip); | |
1601 | } | |
1602 | ||
1603 | /** | |
1604 | * ftrace_text_reserved - return true if range contains an ftrace location | |
1605 | * @start: start of range to search | |
1606 | * @end: end of range to search (inclusive). @end points to the last byte to check. | |
1607 | * | |
1608 | * Returns 1 if @start and @end contains a ftrace location. | |
1609 | * That is, the instruction that is either a NOP or call to | |
1610 | * the function tracer. It checks the ftrace internal tables to | |
1611 | * determine if the address belongs or not. | |
1612 | */ | |
d88471cb | 1613 | int ftrace_text_reserved(const void *start, const void *end) |
a650e02a | 1614 | { |
f0cf973a SR |
1615 | unsigned long ret; |
1616 | ||
1617 | ret = ftrace_location_range((unsigned long)start, | |
1618 | (unsigned long)end); | |
1619 | ||
1620 | return (int)!!ret; | |
a650e02a SR |
1621 | } |
1622 | ||
4fbb48cb SRRH |
1623 | /* Test if ops registered to this rec needs regs */ |
1624 | static bool test_rec_ops_needs_regs(struct dyn_ftrace *rec) | |
1625 | { | |
1626 | struct ftrace_ops *ops; | |
1627 | bool keep_regs = false; | |
1628 | ||
1629 | for (ops = ftrace_ops_list; | |
1630 | ops != &ftrace_list_end; ops = ops->next) { | |
1631 | /* pass rec in as regs to have non-NULL val */ | |
1632 | if (ftrace_ops_test(ops, rec->ip, rec)) { | |
1633 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) { | |
1634 | keep_regs = true; | |
1635 | break; | |
1636 | } | |
1637 | } | |
1638 | } | |
1639 | ||
1640 | return keep_regs; | |
1641 | } | |
1642 | ||
84b6d3e6 | 1643 | static bool __ftrace_hash_rec_update(struct ftrace_ops *ops, |
ed926f9b SR |
1644 | int filter_hash, |
1645 | bool inc) | |
1646 | { | |
1647 | struct ftrace_hash *hash; | |
1648 | struct ftrace_hash *other_hash; | |
1649 | struct ftrace_page *pg; | |
1650 | struct dyn_ftrace *rec; | |
84b6d3e6 | 1651 | bool update = false; |
ed926f9b SR |
1652 | int count = 0; |
1653 | int all = 0; | |
1654 | ||
1655 | /* Only update if the ops has been registered */ | |
1656 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
84b6d3e6 | 1657 | return false; |
ed926f9b SR |
1658 | |
1659 | /* | |
1660 | * In the filter_hash case: | |
1661 | * If the count is zero, we update all records. | |
1662 | * Otherwise we just update the items in the hash. | |
1663 | * | |
1664 | * In the notrace_hash case: | |
1665 | * We enable the update in the hash. | |
1666 | * As disabling notrace means enabling the tracing, | |
1667 | * and enabling notrace means disabling, the inc variable | |
1668 | * gets inversed. | |
1669 | */ | |
1670 | if (filter_hash) { | |
33b7f99c SRRH |
1671 | hash = ops->func_hash->filter_hash; |
1672 | other_hash = ops->func_hash->notrace_hash; | |
06a51d93 | 1673 | if (ftrace_hash_empty(hash)) |
ed926f9b SR |
1674 | all = 1; |
1675 | } else { | |
1676 | inc = !inc; | |
33b7f99c SRRH |
1677 | hash = ops->func_hash->notrace_hash; |
1678 | other_hash = ops->func_hash->filter_hash; | |
ed926f9b SR |
1679 | /* |
1680 | * If the notrace hash has no items, | |
1681 | * then there's nothing to do. | |
1682 | */ | |
06a51d93 | 1683 | if (ftrace_hash_empty(hash)) |
84b6d3e6 | 1684 | return false; |
ed926f9b SR |
1685 | } |
1686 | ||
1687 | do_for_each_ftrace_rec(pg, rec) { | |
1688 | int in_other_hash = 0; | |
1689 | int in_hash = 0; | |
1690 | int match = 0; | |
1691 | ||
b7ffffbb SRRH |
1692 | if (rec->flags & FTRACE_FL_DISABLED) |
1693 | continue; | |
1694 | ||
ed926f9b SR |
1695 | if (all) { |
1696 | /* | |
1697 | * Only the filter_hash affects all records. | |
1698 | * Update if the record is not in the notrace hash. | |
1699 | */ | |
b848914c | 1700 | if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip)) |
ed926f9b SR |
1701 | match = 1; |
1702 | } else { | |
06a51d93 SR |
1703 | in_hash = !!ftrace_lookup_ip(hash, rec->ip); |
1704 | in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip); | |
ed926f9b SR |
1705 | |
1706 | /* | |
19eab4a4 SRRH |
1707 | * If filter_hash is set, we want to match all functions |
1708 | * that are in the hash but not in the other hash. | |
ed926f9b | 1709 | * |
19eab4a4 SRRH |
1710 | * If filter_hash is not set, then we are decrementing. |
1711 | * That means we match anything that is in the hash | |
1712 | * and also in the other_hash. That is, we need to turn | |
1713 | * off functions in the other hash because they are disabled | |
1714 | * by this hash. | |
ed926f9b SR |
1715 | */ |
1716 | if (filter_hash && in_hash && !in_other_hash) | |
1717 | match = 1; | |
1718 | else if (!filter_hash && in_hash && | |
06a51d93 | 1719 | (in_other_hash || ftrace_hash_empty(other_hash))) |
ed926f9b SR |
1720 | match = 1; |
1721 | } | |
1722 | if (!match) | |
1723 | continue; | |
1724 | ||
1725 | if (inc) { | |
1726 | rec->flags++; | |
0376bde1 | 1727 | if (FTRACE_WARN_ON(ftrace_rec_count(rec) == FTRACE_REF_MAX)) |
84b6d3e6 | 1728 | return false; |
79922b80 SRRH |
1729 | |
1730 | /* | |
1731 | * If there's only a single callback registered to a | |
1732 | * function, and the ops has a trampoline registered | |
1733 | * for it, then we can call it directly. | |
1734 | */ | |
fef5aeee | 1735 | if (ftrace_rec_count(rec) == 1 && ops->trampoline) |
79922b80 | 1736 | rec->flags |= FTRACE_FL_TRAMP; |
fef5aeee | 1737 | else |
79922b80 SRRH |
1738 | /* |
1739 | * If we are adding another function callback | |
1740 | * to this function, and the previous had a | |
bce0b6c5 SRRH |
1741 | * custom trampoline in use, then we need to go |
1742 | * back to the default trampoline. | |
79922b80 | 1743 | */ |
fef5aeee | 1744 | rec->flags &= ~FTRACE_FL_TRAMP; |
79922b80 | 1745 | |
08f6fba5 SR |
1746 | /* |
1747 | * If any ops wants regs saved for this function | |
1748 | * then all ops will get saved regs. | |
1749 | */ | |
1750 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) | |
1751 | rec->flags |= FTRACE_FL_REGS; | |
ed926f9b | 1752 | } else { |
0376bde1 | 1753 | if (FTRACE_WARN_ON(ftrace_rec_count(rec) == 0)) |
84b6d3e6 | 1754 | return false; |
ed926f9b | 1755 | rec->flags--; |
79922b80 | 1756 | |
4fbb48cb SRRH |
1757 | /* |
1758 | * If the rec had REGS enabled and the ops that is | |
1759 | * being removed had REGS set, then see if there is | |
1760 | * still any ops for this record that wants regs. | |
1761 | * If not, we can stop recording them. | |
1762 | */ | |
0376bde1 | 1763 | if (ftrace_rec_count(rec) > 0 && |
4fbb48cb SRRH |
1764 | rec->flags & FTRACE_FL_REGS && |
1765 | ops->flags & FTRACE_OPS_FL_SAVE_REGS) { | |
1766 | if (!test_rec_ops_needs_regs(rec)) | |
1767 | rec->flags &= ~FTRACE_FL_REGS; | |
1768 | } | |
79922b80 | 1769 | |
fef5aeee SRRH |
1770 | /* |
1771 | * If the rec had TRAMP enabled, then it needs to | |
1772 | * be cleared. As TRAMP can only be enabled iff | |
1773 | * there is only a single ops attached to it. | |
1774 | * In otherwords, always disable it on decrementing. | |
1775 | * In the future, we may set it if rec count is | |
1776 | * decremented to one, and the ops that is left | |
1777 | * has a trampoline. | |
1778 | */ | |
1779 | rec->flags &= ~FTRACE_FL_TRAMP; | |
1780 | ||
79922b80 SRRH |
1781 | /* |
1782 | * flags will be cleared in ftrace_check_record() | |
1783 | * if rec count is zero. | |
1784 | */ | |
ed926f9b SR |
1785 | } |
1786 | count++; | |
84b6d3e6 JO |
1787 | |
1788 | /* Must match FTRACE_UPDATE_CALLS in ftrace_modify_all_code() */ | |
1789 | update |= ftrace_test_record(rec, 1) != FTRACE_UPDATE_IGNORE; | |
1790 | ||
ed926f9b SR |
1791 | /* Shortcut, if we handled all records, we are done. */ |
1792 | if (!all && count == hash->count) | |
84b6d3e6 | 1793 | return update; |
ed926f9b | 1794 | } while_for_each_ftrace_rec(); |
84b6d3e6 JO |
1795 | |
1796 | return update; | |
ed926f9b SR |
1797 | } |
1798 | ||
84b6d3e6 | 1799 | static bool ftrace_hash_rec_disable(struct ftrace_ops *ops, |
ed926f9b SR |
1800 | int filter_hash) |
1801 | { | |
84b6d3e6 | 1802 | return __ftrace_hash_rec_update(ops, filter_hash, 0); |
ed926f9b SR |
1803 | } |
1804 | ||
84b6d3e6 | 1805 | static bool ftrace_hash_rec_enable(struct ftrace_ops *ops, |
ed926f9b SR |
1806 | int filter_hash) |
1807 | { | |
84b6d3e6 | 1808 | return __ftrace_hash_rec_update(ops, filter_hash, 1); |
ed926f9b SR |
1809 | } |
1810 | ||
84261912 SRRH |
1811 | static void ftrace_hash_rec_update_modify(struct ftrace_ops *ops, |
1812 | int filter_hash, int inc) | |
1813 | { | |
1814 | struct ftrace_ops *op; | |
1815 | ||
1816 | __ftrace_hash_rec_update(ops, filter_hash, inc); | |
1817 | ||
1818 | if (ops->func_hash != &global_ops.local_hash) | |
1819 | return; | |
1820 | ||
1821 | /* | |
1822 | * If the ops shares the global_ops hash, then we need to update | |
1823 | * all ops that are enabled and use this hash. | |
1824 | */ | |
1825 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
1826 | /* Already done */ | |
1827 | if (op == ops) | |
1828 | continue; | |
1829 | if (op->func_hash == &global_ops.local_hash) | |
1830 | __ftrace_hash_rec_update(op, filter_hash, inc); | |
1831 | } while_for_each_ftrace_op(op); | |
1832 | } | |
1833 | ||
1834 | static void ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, | |
1835 | int filter_hash) | |
1836 | { | |
1837 | ftrace_hash_rec_update_modify(ops, filter_hash, 0); | |
1838 | } | |
1839 | ||
1840 | static void ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, | |
1841 | int filter_hash) | |
1842 | { | |
1843 | ftrace_hash_rec_update_modify(ops, filter_hash, 1); | |
1844 | } | |
1845 | ||
f8b8be8a MH |
1846 | /* |
1847 | * Try to update IPMODIFY flag on each ftrace_rec. Return 0 if it is OK | |
1848 | * or no-needed to update, -EBUSY if it detects a conflict of the flag | |
1849 | * on a ftrace_rec, and -EINVAL if the new_hash tries to trace all recs. | |
1850 | * Note that old_hash and new_hash has below meanings | |
1851 | * - If the hash is NULL, it hits all recs (if IPMODIFY is set, this is rejected) | |
1852 | * - If the hash is EMPTY_HASH, it hits nothing | |
1853 | * - Anything else hits the recs which match the hash entries. | |
1854 | */ | |
1855 | static int __ftrace_hash_update_ipmodify(struct ftrace_ops *ops, | |
1856 | struct ftrace_hash *old_hash, | |
1857 | struct ftrace_hash *new_hash) | |
1858 | { | |
1859 | struct ftrace_page *pg; | |
1860 | struct dyn_ftrace *rec, *end = NULL; | |
1861 | int in_old, in_new; | |
1862 | ||
1863 | /* Only update if the ops has been registered */ | |
1864 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
1865 | return 0; | |
1866 | ||
1867 | if (!(ops->flags & FTRACE_OPS_FL_IPMODIFY)) | |
1868 | return 0; | |
1869 | ||
1870 | /* | |
1871 | * Since the IPMODIFY is a very address sensitive action, we do not | |
1872 | * allow ftrace_ops to set all functions to new hash. | |
1873 | */ | |
1874 | if (!new_hash || !old_hash) | |
1875 | return -EINVAL; | |
1876 | ||
1877 | /* Update rec->flags */ | |
1878 | do_for_each_ftrace_rec(pg, rec) { | |
546fece4 SRRH |
1879 | |
1880 | if (rec->flags & FTRACE_FL_DISABLED) | |
1881 | continue; | |
1882 | ||
f8b8be8a MH |
1883 | /* We need to update only differences of filter_hash */ |
1884 | in_old = !!ftrace_lookup_ip(old_hash, rec->ip); | |
1885 | in_new = !!ftrace_lookup_ip(new_hash, rec->ip); | |
1886 | if (in_old == in_new) | |
1887 | continue; | |
1888 | ||
1889 | if (in_new) { | |
1890 | /* New entries must ensure no others are using it */ | |
1891 | if (rec->flags & FTRACE_FL_IPMODIFY) | |
1892 | goto rollback; | |
1893 | rec->flags |= FTRACE_FL_IPMODIFY; | |
1894 | } else /* Removed entry */ | |
1895 | rec->flags &= ~FTRACE_FL_IPMODIFY; | |
1896 | } while_for_each_ftrace_rec(); | |
1897 | ||
1898 | return 0; | |
1899 | ||
1900 | rollback: | |
1901 | end = rec; | |
1902 | ||
1903 | /* Roll back what we did above */ | |
1904 | do_for_each_ftrace_rec(pg, rec) { | |
546fece4 SRRH |
1905 | |
1906 | if (rec->flags & FTRACE_FL_DISABLED) | |
1907 | continue; | |
1908 | ||
f8b8be8a MH |
1909 | if (rec == end) |
1910 | goto err_out; | |
1911 | ||
1912 | in_old = !!ftrace_lookup_ip(old_hash, rec->ip); | |
1913 | in_new = !!ftrace_lookup_ip(new_hash, rec->ip); | |
1914 | if (in_old == in_new) | |
1915 | continue; | |
1916 | ||
1917 | if (in_new) | |
1918 | rec->flags &= ~FTRACE_FL_IPMODIFY; | |
1919 | else | |
1920 | rec->flags |= FTRACE_FL_IPMODIFY; | |
1921 | } while_for_each_ftrace_rec(); | |
1922 | ||
1923 | err_out: | |
1924 | return -EBUSY; | |
1925 | } | |
1926 | ||
1927 | static int ftrace_hash_ipmodify_enable(struct ftrace_ops *ops) | |
1928 | { | |
1929 | struct ftrace_hash *hash = ops->func_hash->filter_hash; | |
1930 | ||
1931 | if (ftrace_hash_empty(hash)) | |
1932 | hash = NULL; | |
1933 | ||
1934 | return __ftrace_hash_update_ipmodify(ops, EMPTY_HASH, hash); | |
1935 | } | |
1936 | ||
1937 | /* Disabling always succeeds */ | |
1938 | static void ftrace_hash_ipmodify_disable(struct ftrace_ops *ops) | |
1939 | { | |
1940 | struct ftrace_hash *hash = ops->func_hash->filter_hash; | |
1941 | ||
1942 | if (ftrace_hash_empty(hash)) | |
1943 | hash = NULL; | |
1944 | ||
1945 | __ftrace_hash_update_ipmodify(ops, hash, EMPTY_HASH); | |
1946 | } | |
1947 | ||
1948 | static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops, | |
1949 | struct ftrace_hash *new_hash) | |
1950 | { | |
1951 | struct ftrace_hash *old_hash = ops->func_hash->filter_hash; | |
1952 | ||
1953 | if (ftrace_hash_empty(old_hash)) | |
1954 | old_hash = NULL; | |
1955 | ||
1956 | if (ftrace_hash_empty(new_hash)) | |
1957 | new_hash = NULL; | |
1958 | ||
1959 | return __ftrace_hash_update_ipmodify(ops, old_hash, new_hash); | |
1960 | } | |
1961 | ||
b05086c7 | 1962 | static void print_ip_ins(const char *fmt, const unsigned char *p) |
b17e8a37 SR |
1963 | { |
1964 | int i; | |
1965 | ||
1966 | printk(KERN_CONT "%s", fmt); | |
1967 | ||
1968 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
1969 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
1970 | } | |
1971 | ||
4fd3279b SRRH |
1972 | static struct ftrace_ops * |
1973 | ftrace_find_tramp_ops_any(struct dyn_ftrace *rec); | |
39daa7b9 SRRH |
1974 | static struct ftrace_ops * |
1975 | ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, struct ftrace_ops *ops); | |
4fd3279b | 1976 | |
02a392a0 | 1977 | enum ftrace_bug_type ftrace_bug_type; |
b05086c7 | 1978 | const void *ftrace_expected; |
02a392a0 SRRH |
1979 | |
1980 | static void print_bug_type(void) | |
1981 | { | |
1982 | switch (ftrace_bug_type) { | |
1983 | case FTRACE_BUG_UNKNOWN: | |
1984 | break; | |
1985 | case FTRACE_BUG_INIT: | |
1986 | pr_info("Initializing ftrace call sites\n"); | |
1987 | break; | |
1988 | case FTRACE_BUG_NOP: | |
1989 | pr_info("Setting ftrace call site to NOP\n"); | |
1990 | break; | |
1991 | case FTRACE_BUG_CALL: | |
1992 | pr_info("Setting ftrace call site to call ftrace function\n"); | |
1993 | break; | |
1994 | case FTRACE_BUG_UPDATE: | |
1995 | pr_info("Updating ftrace call site to call a different ftrace function\n"); | |
1996 | break; | |
1997 | } | |
1998 | } | |
1999 | ||
c88fd863 SR |
2000 | /** |
2001 | * ftrace_bug - report and shutdown function tracer | |
2002 | * @failed: The failed type (EFAULT, EINVAL, EPERM) | |
4fd3279b | 2003 | * @rec: The record that failed |
c88fd863 SR |
2004 | * |
2005 | * The arch code that enables or disables the function tracing | |
2006 | * can call ftrace_bug() when it has detected a problem in | |
2007 | * modifying the code. @failed should be one of either: | |
2008 | * EFAULT - if the problem happens on reading the @ip address | |
2009 | * EINVAL - if what is read at @ip is not what was expected | |
2010 | * EPERM - if the problem happens on writting to the @ip address | |
2011 | */ | |
4fd3279b | 2012 | void ftrace_bug(int failed, struct dyn_ftrace *rec) |
b17e8a37 | 2013 | { |
4fd3279b SRRH |
2014 | unsigned long ip = rec ? rec->ip : 0; |
2015 | ||
b17e8a37 SR |
2016 | switch (failed) { |
2017 | case -EFAULT: | |
2018 | FTRACE_WARN_ON_ONCE(1); | |
2019 | pr_info("ftrace faulted on modifying "); | |
2020 | print_ip_sym(ip); | |
2021 | break; | |
2022 | case -EINVAL: | |
2023 | FTRACE_WARN_ON_ONCE(1); | |
2024 | pr_info("ftrace failed to modify "); | |
2025 | print_ip_sym(ip); | |
b05086c7 | 2026 | print_ip_ins(" actual: ", (unsigned char *)ip); |
4fd3279b | 2027 | pr_cont("\n"); |
b05086c7 SRRH |
2028 | if (ftrace_expected) { |
2029 | print_ip_ins(" expected: ", ftrace_expected); | |
2030 | pr_cont("\n"); | |
2031 | } | |
b17e8a37 SR |
2032 | break; |
2033 | case -EPERM: | |
2034 | FTRACE_WARN_ON_ONCE(1); | |
2035 | pr_info("ftrace faulted on writing "); | |
2036 | print_ip_sym(ip); | |
2037 | break; | |
2038 | default: | |
2039 | FTRACE_WARN_ON_ONCE(1); | |
2040 | pr_info("ftrace faulted on unknown error "); | |
2041 | print_ip_sym(ip); | |
2042 | } | |
02a392a0 | 2043 | print_bug_type(); |
4fd3279b SRRH |
2044 | if (rec) { |
2045 | struct ftrace_ops *ops = NULL; | |
2046 | ||
2047 | pr_info("ftrace record flags: %lx\n", rec->flags); | |
2048 | pr_cont(" (%ld)%s", ftrace_rec_count(rec), | |
2049 | rec->flags & FTRACE_FL_REGS ? " R" : " "); | |
2050 | if (rec->flags & FTRACE_FL_TRAMP_EN) { | |
2051 | ops = ftrace_find_tramp_ops_any(rec); | |
39daa7b9 SRRH |
2052 | if (ops) { |
2053 | do { | |
2054 | pr_cont("\ttramp: %pS (%pS)", | |
2055 | (void *)ops->trampoline, | |
2056 | (void *)ops->func); | |
2057 | ops = ftrace_find_tramp_ops_next(rec, ops); | |
2058 | } while (ops); | |
2059 | } else | |
4fd3279b SRRH |
2060 | pr_cont("\ttramp: ERROR!"); |
2061 | ||
2062 | } | |
2063 | ip = ftrace_get_addr_curr(rec); | |
39daa7b9 | 2064 | pr_cont("\n expected tramp: %lx\n", ip); |
4fd3279b | 2065 | } |
b17e8a37 SR |
2066 | } |
2067 | ||
c88fd863 | 2068 | static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update) |
5072c59f | 2069 | { |
64fbcd16 | 2070 | unsigned long flag = 0UL; |
e7d3737e | 2071 | |
02a392a0 SRRH |
2072 | ftrace_bug_type = FTRACE_BUG_UNKNOWN; |
2073 | ||
b7ffffbb SRRH |
2074 | if (rec->flags & FTRACE_FL_DISABLED) |
2075 | return FTRACE_UPDATE_IGNORE; | |
2076 | ||
982c350b | 2077 | /* |
30fb6aa7 | 2078 | * If we are updating calls: |
982c350b | 2079 | * |
ed926f9b SR |
2080 | * If the record has a ref count, then we need to enable it |
2081 | * because someone is using it. | |
982c350b | 2082 | * |
ed926f9b SR |
2083 | * Otherwise we make sure its disabled. |
2084 | * | |
30fb6aa7 | 2085 | * If we are disabling calls, then disable all records that |
ed926f9b | 2086 | * are enabled. |
982c350b | 2087 | */ |
0376bde1 | 2088 | if (enable && ftrace_rec_count(rec)) |
ed926f9b | 2089 | flag = FTRACE_FL_ENABLED; |
982c350b | 2090 | |
08f6fba5 | 2091 | /* |
79922b80 SRRH |
2092 | * If enabling and the REGS flag does not match the REGS_EN, or |
2093 | * the TRAMP flag doesn't match the TRAMP_EN, then do not ignore | |
2094 | * this record. Set flags to fail the compare against ENABLED. | |
08f6fba5 | 2095 | */ |
79922b80 SRRH |
2096 | if (flag) { |
2097 | if (!(rec->flags & FTRACE_FL_REGS) != | |
2098 | !(rec->flags & FTRACE_FL_REGS_EN)) | |
2099 | flag |= FTRACE_FL_REGS; | |
2100 | ||
2101 | if (!(rec->flags & FTRACE_FL_TRAMP) != | |
2102 | !(rec->flags & FTRACE_FL_TRAMP_EN)) | |
2103 | flag |= FTRACE_FL_TRAMP; | |
2104 | } | |
08f6fba5 | 2105 | |
64fbcd16 XG |
2106 | /* If the state of this record hasn't changed, then do nothing */ |
2107 | if ((rec->flags & FTRACE_FL_ENABLED) == flag) | |
c88fd863 | 2108 | return FTRACE_UPDATE_IGNORE; |
982c350b | 2109 | |
64fbcd16 | 2110 | if (flag) { |
08f6fba5 SR |
2111 | /* Save off if rec is being enabled (for return value) */ |
2112 | flag ^= rec->flags & FTRACE_FL_ENABLED; | |
2113 | ||
2114 | if (update) { | |
c88fd863 | 2115 | rec->flags |= FTRACE_FL_ENABLED; |
08f6fba5 SR |
2116 | if (flag & FTRACE_FL_REGS) { |
2117 | if (rec->flags & FTRACE_FL_REGS) | |
2118 | rec->flags |= FTRACE_FL_REGS_EN; | |
2119 | else | |
2120 | rec->flags &= ~FTRACE_FL_REGS_EN; | |
2121 | } | |
79922b80 SRRH |
2122 | if (flag & FTRACE_FL_TRAMP) { |
2123 | if (rec->flags & FTRACE_FL_TRAMP) | |
2124 | rec->flags |= FTRACE_FL_TRAMP_EN; | |
2125 | else | |
2126 | rec->flags &= ~FTRACE_FL_TRAMP_EN; | |
2127 | } | |
08f6fba5 SR |
2128 | } |
2129 | ||
2130 | /* | |
2131 | * If this record is being updated from a nop, then | |
2132 | * return UPDATE_MAKE_CALL. | |
08f6fba5 SR |
2133 | * Otherwise, |
2134 | * return UPDATE_MODIFY_CALL to tell the caller to convert | |
f1b2f2bd | 2135 | * from the save regs, to a non-save regs function or |
79922b80 | 2136 | * vice versa, or from a trampoline call. |
08f6fba5 | 2137 | */ |
02a392a0 SRRH |
2138 | if (flag & FTRACE_FL_ENABLED) { |
2139 | ftrace_bug_type = FTRACE_BUG_CALL; | |
08f6fba5 | 2140 | return FTRACE_UPDATE_MAKE_CALL; |
02a392a0 | 2141 | } |
f1b2f2bd | 2142 | |
02a392a0 | 2143 | ftrace_bug_type = FTRACE_BUG_UPDATE; |
f1b2f2bd | 2144 | return FTRACE_UPDATE_MODIFY_CALL; |
c88fd863 SR |
2145 | } |
2146 | ||
08f6fba5 SR |
2147 | if (update) { |
2148 | /* If there's no more users, clear all flags */ | |
0376bde1 | 2149 | if (!ftrace_rec_count(rec)) |
08f6fba5 SR |
2150 | rec->flags = 0; |
2151 | else | |
b24d443b SRRH |
2152 | /* |
2153 | * Just disable the record, but keep the ops TRAMP | |
2154 | * and REGS states. The _EN flags must be disabled though. | |
2155 | */ | |
2156 | rec->flags &= ~(FTRACE_FL_ENABLED | FTRACE_FL_TRAMP_EN | | |
2157 | FTRACE_FL_REGS_EN); | |
08f6fba5 | 2158 | } |
c88fd863 | 2159 | |
02a392a0 | 2160 | ftrace_bug_type = FTRACE_BUG_NOP; |
c88fd863 SR |
2161 | return FTRACE_UPDATE_MAKE_NOP; |
2162 | } | |
2163 | ||
2164 | /** | |
2165 | * ftrace_update_record, set a record that now is tracing or not | |
2166 | * @rec: the record to update | |
2167 | * @enable: set to 1 if the record is tracing, zero to force disable | |
2168 | * | |
2169 | * The records that represent all functions that can be traced need | |
2170 | * to be updated when tracing has been enabled. | |
2171 | */ | |
2172 | int ftrace_update_record(struct dyn_ftrace *rec, int enable) | |
2173 | { | |
2174 | return ftrace_check_record(rec, enable, 1); | |
2175 | } | |
2176 | ||
2177 | /** | |
2178 | * ftrace_test_record, check if the record has been enabled or not | |
2179 | * @rec: the record to test | |
2180 | * @enable: set to 1 to check if enabled, 0 if it is disabled | |
2181 | * | |
2182 | * The arch code may need to test if a record is already set to | |
2183 | * tracing to determine how to modify the function code that it | |
2184 | * represents. | |
2185 | */ | |
2186 | int ftrace_test_record(struct dyn_ftrace *rec, int enable) | |
2187 | { | |
2188 | return ftrace_check_record(rec, enable, 0); | |
2189 | } | |
2190 | ||
5fecaa04 SRRH |
2191 | static struct ftrace_ops * |
2192 | ftrace_find_tramp_ops_any(struct dyn_ftrace *rec) | |
2193 | { | |
2194 | struct ftrace_ops *op; | |
fef5aeee | 2195 | unsigned long ip = rec->ip; |
5fecaa04 SRRH |
2196 | |
2197 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
2198 | ||
2199 | if (!op->trampoline) | |
2200 | continue; | |
2201 | ||
fef5aeee | 2202 | if (hash_contains_ip(ip, op->func_hash)) |
5fecaa04 SRRH |
2203 | return op; |
2204 | } while_for_each_ftrace_op(op); | |
2205 | ||
2206 | return NULL; | |
2207 | } | |
2208 | ||
39daa7b9 SRRH |
2209 | static struct ftrace_ops * |
2210 | ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, | |
2211 | struct ftrace_ops *op) | |
2212 | { | |
2213 | unsigned long ip = rec->ip; | |
2214 | ||
2215 | while_for_each_ftrace_op(op) { | |
2216 | ||
2217 | if (!op->trampoline) | |
2218 | continue; | |
2219 | ||
2220 | if (hash_contains_ip(ip, op->func_hash)) | |
2221 | return op; | |
2222 | } | |
2223 | ||
2224 | return NULL; | |
2225 | } | |
2226 | ||
79922b80 SRRH |
2227 | static struct ftrace_ops * |
2228 | ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec) | |
2229 | { | |
2230 | struct ftrace_ops *op; | |
fef5aeee | 2231 | unsigned long ip = rec->ip; |
79922b80 | 2232 | |
fef5aeee SRRH |
2233 | /* |
2234 | * Need to check removed ops first. | |
2235 | * If they are being removed, and this rec has a tramp, | |
2236 | * and this rec is in the ops list, then it would be the | |
2237 | * one with the tramp. | |
2238 | */ | |
2239 | if (removed_ops) { | |
2240 | if (hash_contains_ip(ip, &removed_ops->old_hash)) | |
79922b80 SRRH |
2241 | return removed_ops; |
2242 | } | |
2243 | ||
fef5aeee SRRH |
2244 | /* |
2245 | * Need to find the current trampoline for a rec. | |
2246 | * Now, a trampoline is only attached to a rec if there | |
2247 | * was a single 'ops' attached to it. But this can be called | |
2248 | * when we are adding another op to the rec or removing the | |
2249 | * current one. Thus, if the op is being added, we can | |
2250 | * ignore it because it hasn't attached itself to the rec | |
4fc40904 SRRH |
2251 | * yet. |
2252 | * | |
2253 | * If an ops is being modified (hooking to different functions) | |
2254 | * then we don't care about the new functions that are being | |
2255 | * added, just the old ones (that are probably being removed). | |
2256 | * | |
2257 | * If we are adding an ops to a function that already is using | |
2258 | * a trampoline, it needs to be removed (trampolines are only | |
2259 | * for single ops connected), then an ops that is not being | |
2260 | * modified also needs to be checked. | |
fef5aeee | 2261 | */ |
79922b80 | 2262 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
fef5aeee SRRH |
2263 | |
2264 | if (!op->trampoline) | |
2265 | continue; | |
2266 | ||
2267 | /* | |
2268 | * If the ops is being added, it hasn't gotten to | |
2269 | * the point to be removed from this tree yet. | |
2270 | */ | |
2271 | if (op->flags & FTRACE_OPS_FL_ADDING) | |
79922b80 SRRH |
2272 | continue; |
2273 | ||
4fc40904 | 2274 | |
fef5aeee | 2275 | /* |
4fc40904 SRRH |
2276 | * If the ops is being modified and is in the old |
2277 | * hash, then it is probably being removed from this | |
2278 | * function. | |
fef5aeee | 2279 | */ |
fef5aeee SRRH |
2280 | if ((op->flags & FTRACE_OPS_FL_MODIFYING) && |
2281 | hash_contains_ip(ip, &op->old_hash)) | |
79922b80 | 2282 | return op; |
4fc40904 SRRH |
2283 | /* |
2284 | * If the ops is not being added or modified, and it's | |
2285 | * in its normal filter hash, then this must be the one | |
2286 | * we want! | |
2287 | */ | |
2288 | if (!(op->flags & FTRACE_OPS_FL_MODIFYING) && | |
2289 | hash_contains_ip(ip, op->func_hash)) | |
2290 | return op; | |
79922b80 SRRH |
2291 | |
2292 | } while_for_each_ftrace_op(op); | |
2293 | ||
2294 | return NULL; | |
2295 | } | |
2296 | ||
2297 | static struct ftrace_ops * | |
2298 | ftrace_find_tramp_ops_new(struct dyn_ftrace *rec) | |
2299 | { | |
2300 | struct ftrace_ops *op; | |
fef5aeee | 2301 | unsigned long ip = rec->ip; |
79922b80 SRRH |
2302 | |
2303 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
2304 | /* pass rec in as regs to have non-NULL val */ | |
fef5aeee | 2305 | if (hash_contains_ip(ip, op->func_hash)) |
79922b80 SRRH |
2306 | return op; |
2307 | } while_for_each_ftrace_op(op); | |
2308 | ||
2309 | return NULL; | |
2310 | } | |
2311 | ||
7413af1f SRRH |
2312 | /** |
2313 | * ftrace_get_addr_new - Get the call address to set to | |
2314 | * @rec: The ftrace record descriptor | |
2315 | * | |
2316 | * If the record has the FTRACE_FL_REGS set, that means that it | |
2317 | * wants to convert to a callback that saves all regs. If FTRACE_FL_REGS | |
2318 | * is not not set, then it wants to convert to the normal callback. | |
2319 | * | |
2320 | * Returns the address of the trampoline to set to | |
2321 | */ | |
2322 | unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec) | |
2323 | { | |
79922b80 SRRH |
2324 | struct ftrace_ops *ops; |
2325 | ||
2326 | /* Trampolines take precedence over regs */ | |
2327 | if (rec->flags & FTRACE_FL_TRAMP) { | |
2328 | ops = ftrace_find_tramp_ops_new(rec); | |
2329 | if (FTRACE_WARN_ON(!ops || !ops->trampoline)) { | |
bce0b6c5 SRRH |
2330 | pr_warn("Bad trampoline accounting at: %p (%pS) (%lx)\n", |
2331 | (void *)rec->ip, (void *)rec->ip, rec->flags); | |
79922b80 SRRH |
2332 | /* Ftrace is shutting down, return anything */ |
2333 | return (unsigned long)FTRACE_ADDR; | |
2334 | } | |
2335 | return ops->trampoline; | |
2336 | } | |
2337 | ||
7413af1f SRRH |
2338 | if (rec->flags & FTRACE_FL_REGS) |
2339 | return (unsigned long)FTRACE_REGS_ADDR; | |
2340 | else | |
2341 | return (unsigned long)FTRACE_ADDR; | |
2342 | } | |
2343 | ||
2344 | /** | |
2345 | * ftrace_get_addr_curr - Get the call address that is already there | |
2346 | * @rec: The ftrace record descriptor | |
2347 | * | |
2348 | * The FTRACE_FL_REGS_EN is set when the record already points to | |
2349 | * a function that saves all the regs. Basically the '_EN' version | |
2350 | * represents the current state of the function. | |
2351 | * | |
2352 | * Returns the address of the trampoline that is currently being called | |
2353 | */ | |
2354 | unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec) | |
2355 | { | |
79922b80 SRRH |
2356 | struct ftrace_ops *ops; |
2357 | ||
2358 | /* Trampolines take precedence over regs */ | |
2359 | if (rec->flags & FTRACE_FL_TRAMP_EN) { | |
2360 | ops = ftrace_find_tramp_ops_curr(rec); | |
2361 | if (FTRACE_WARN_ON(!ops)) { | |
a395d6a7 JP |
2362 | pr_warn("Bad trampoline accounting at: %p (%pS)\n", |
2363 | (void *)rec->ip, (void *)rec->ip); | |
79922b80 SRRH |
2364 | /* Ftrace is shutting down, return anything */ |
2365 | return (unsigned long)FTRACE_ADDR; | |
2366 | } | |
2367 | return ops->trampoline; | |
2368 | } | |
2369 | ||
7413af1f SRRH |
2370 | if (rec->flags & FTRACE_FL_REGS_EN) |
2371 | return (unsigned long)FTRACE_REGS_ADDR; | |
2372 | else | |
2373 | return (unsigned long)FTRACE_ADDR; | |
2374 | } | |
2375 | ||
c88fd863 SR |
2376 | static int |
2377 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) | |
2378 | { | |
08f6fba5 | 2379 | unsigned long ftrace_old_addr; |
c88fd863 SR |
2380 | unsigned long ftrace_addr; |
2381 | int ret; | |
2382 | ||
7c0868e0 | 2383 | ftrace_addr = ftrace_get_addr_new(rec); |
c88fd863 | 2384 | |
7c0868e0 SRRH |
2385 | /* This needs to be done before we call ftrace_update_record */ |
2386 | ftrace_old_addr = ftrace_get_addr_curr(rec); | |
2387 | ||
2388 | ret = ftrace_update_record(rec, enable); | |
08f6fba5 | 2389 | |
02a392a0 SRRH |
2390 | ftrace_bug_type = FTRACE_BUG_UNKNOWN; |
2391 | ||
c88fd863 SR |
2392 | switch (ret) { |
2393 | case FTRACE_UPDATE_IGNORE: | |
2394 | return 0; | |
2395 | ||
2396 | case FTRACE_UPDATE_MAKE_CALL: | |
02a392a0 | 2397 | ftrace_bug_type = FTRACE_BUG_CALL; |
64fbcd16 | 2398 | return ftrace_make_call(rec, ftrace_addr); |
c88fd863 SR |
2399 | |
2400 | case FTRACE_UPDATE_MAKE_NOP: | |
02a392a0 | 2401 | ftrace_bug_type = FTRACE_BUG_NOP; |
39b5552c | 2402 | return ftrace_make_nop(NULL, rec, ftrace_old_addr); |
08f6fba5 | 2403 | |
08f6fba5 | 2404 | case FTRACE_UPDATE_MODIFY_CALL: |
02a392a0 | 2405 | ftrace_bug_type = FTRACE_BUG_UPDATE; |
08f6fba5 | 2406 | return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr); |
5072c59f SR |
2407 | } |
2408 | ||
c88fd863 | 2409 | return -1; /* unknow ftrace bug */ |
5072c59f SR |
2410 | } |
2411 | ||
e4f5d544 | 2412 | void __weak ftrace_replace_code(int enable) |
3c1720f0 | 2413 | { |
3c1720f0 SR |
2414 | struct dyn_ftrace *rec; |
2415 | struct ftrace_page *pg; | |
6a24a244 | 2416 | int failed; |
3c1720f0 | 2417 | |
45a4a237 SR |
2418 | if (unlikely(ftrace_disabled)) |
2419 | return; | |
2420 | ||
265c831c | 2421 | do_for_each_ftrace_rec(pg, rec) { |
546fece4 SRRH |
2422 | |
2423 | if (rec->flags & FTRACE_FL_DISABLED) | |
2424 | continue; | |
2425 | ||
e4f5d544 | 2426 | failed = __ftrace_replace_code(rec, enable); |
fa9d13cf | 2427 | if (failed) { |
4fd3279b | 2428 | ftrace_bug(failed, rec); |
3279ba37 SR |
2429 | /* Stop processing */ |
2430 | return; | |
3c1720f0 | 2431 | } |
265c831c | 2432 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
2433 | } |
2434 | ||
c88fd863 SR |
2435 | struct ftrace_rec_iter { |
2436 | struct ftrace_page *pg; | |
2437 | int index; | |
2438 | }; | |
2439 | ||
2440 | /** | |
2441 | * ftrace_rec_iter_start, start up iterating over traced functions | |
2442 | * | |
2443 | * Returns an iterator handle that is used to iterate over all | |
2444 | * the records that represent address locations where functions | |
2445 | * are traced. | |
2446 | * | |
2447 | * May return NULL if no records are available. | |
2448 | */ | |
2449 | struct ftrace_rec_iter *ftrace_rec_iter_start(void) | |
2450 | { | |
2451 | /* | |
2452 | * We only use a single iterator. | |
2453 | * Protected by the ftrace_lock mutex. | |
2454 | */ | |
2455 | static struct ftrace_rec_iter ftrace_rec_iter; | |
2456 | struct ftrace_rec_iter *iter = &ftrace_rec_iter; | |
2457 | ||
2458 | iter->pg = ftrace_pages_start; | |
2459 | iter->index = 0; | |
2460 | ||
2461 | /* Could have empty pages */ | |
2462 | while (iter->pg && !iter->pg->index) | |
2463 | iter->pg = iter->pg->next; | |
2464 | ||
2465 | if (!iter->pg) | |
2466 | return NULL; | |
2467 | ||
2468 | return iter; | |
2469 | } | |
2470 | ||
2471 | /** | |
2472 | * ftrace_rec_iter_next, get the next record to process. | |
2473 | * @iter: The handle to the iterator. | |
2474 | * | |
2475 | * Returns the next iterator after the given iterator @iter. | |
2476 | */ | |
2477 | struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter) | |
2478 | { | |
2479 | iter->index++; | |
2480 | ||
2481 | if (iter->index >= iter->pg->index) { | |
2482 | iter->pg = iter->pg->next; | |
2483 | iter->index = 0; | |
2484 | ||
2485 | /* Could have empty pages */ | |
2486 | while (iter->pg && !iter->pg->index) | |
2487 | iter->pg = iter->pg->next; | |
2488 | } | |
2489 | ||
2490 | if (!iter->pg) | |
2491 | return NULL; | |
2492 | ||
2493 | return iter; | |
2494 | } | |
2495 | ||
2496 | /** | |
2497 | * ftrace_rec_iter_record, get the record at the iterator location | |
2498 | * @iter: The current iterator location | |
2499 | * | |
2500 | * Returns the record that the current @iter is at. | |
2501 | */ | |
2502 | struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter) | |
2503 | { | |
2504 | return &iter->pg->records[iter->index]; | |
2505 | } | |
2506 | ||
492a7ea5 | 2507 | static int |
31e88909 | 2508 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 | 2509 | { |
593eb8a2 | 2510 | int ret; |
3c1720f0 | 2511 | |
45a4a237 SR |
2512 | if (unlikely(ftrace_disabled)) |
2513 | return 0; | |
2514 | ||
25aac9dc | 2515 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
593eb8a2 | 2516 | if (ret) { |
02a392a0 | 2517 | ftrace_bug_type = FTRACE_BUG_INIT; |
4fd3279b | 2518 | ftrace_bug(ret, rec); |
492a7ea5 | 2519 | return 0; |
37ad5084 | 2520 | } |
492a7ea5 | 2521 | return 1; |
3c1720f0 SR |
2522 | } |
2523 | ||
000ab691 SR |
2524 | /* |
2525 | * archs can override this function if they must do something | |
2526 | * before the modifying code is performed. | |
2527 | */ | |
2528 | int __weak ftrace_arch_code_modify_prepare(void) | |
2529 | { | |
2530 | return 0; | |
2531 | } | |
2532 | ||
2533 | /* | |
2534 | * archs can override this function if they must do something | |
2535 | * after the modifying code is performed. | |
2536 | */ | |
2537 | int __weak ftrace_arch_code_modify_post_process(void) | |
2538 | { | |
2539 | return 0; | |
2540 | } | |
2541 | ||
8ed3e2cf | 2542 | void ftrace_modify_all_code(int command) |
3d083395 | 2543 | { |
59338f75 | 2544 | int update = command & FTRACE_UPDATE_TRACE_FUNC; |
cd21067f | 2545 | int err = 0; |
59338f75 SRRH |
2546 | |
2547 | /* | |
2548 | * If the ftrace_caller calls a ftrace_ops func directly, | |
2549 | * we need to make sure that it only traces functions it | |
2550 | * expects to trace. When doing the switch of functions, | |
2551 | * we need to update to the ftrace_ops_list_func first | |
2552 | * before the transition between old and new calls are set, | |
2553 | * as the ftrace_ops_list_func will check the ops hashes | |
2554 | * to make sure the ops are having the right functions | |
2555 | * traced. | |
2556 | */ | |
cd21067f PM |
2557 | if (update) { |
2558 | err = ftrace_update_ftrace_func(ftrace_ops_list_func); | |
2559 | if (FTRACE_WARN_ON(err)) | |
2560 | return; | |
2561 | } | |
59338f75 | 2562 | |
8ed3e2cf | 2563 | if (command & FTRACE_UPDATE_CALLS) |
d61f82d0 | 2564 | ftrace_replace_code(1); |
8ed3e2cf | 2565 | else if (command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
2566 | ftrace_replace_code(0); |
2567 | ||
405e1d83 SRRH |
2568 | if (update && ftrace_trace_function != ftrace_ops_list_func) { |
2569 | function_trace_op = set_function_trace_op; | |
2570 | smp_wmb(); | |
2571 | /* If irqs are disabled, we are in stop machine */ | |
2572 | if (!irqs_disabled()) | |
2573 | smp_call_function(ftrace_sync_ipi, NULL, 1); | |
cd21067f PM |
2574 | err = ftrace_update_ftrace_func(ftrace_trace_function); |
2575 | if (FTRACE_WARN_ON(err)) | |
2576 | return; | |
405e1d83 | 2577 | } |
d61f82d0 | 2578 | |
8ed3e2cf | 2579 | if (command & FTRACE_START_FUNC_RET) |
cd21067f | 2580 | err = ftrace_enable_ftrace_graph_caller(); |
8ed3e2cf | 2581 | else if (command & FTRACE_STOP_FUNC_RET) |
cd21067f PM |
2582 | err = ftrace_disable_ftrace_graph_caller(); |
2583 | FTRACE_WARN_ON(err); | |
8ed3e2cf SR |
2584 | } |
2585 | ||
2586 | static int __ftrace_modify_code(void *data) | |
2587 | { | |
2588 | int *command = data; | |
2589 | ||
2590 | ftrace_modify_all_code(*command); | |
5a45cfe1 | 2591 | |
d61f82d0 | 2592 | return 0; |
3d083395 SR |
2593 | } |
2594 | ||
c88fd863 SR |
2595 | /** |
2596 | * ftrace_run_stop_machine, go back to the stop machine method | |
2597 | * @command: The command to tell ftrace what to do | |
2598 | * | |
2599 | * If an arch needs to fall back to the stop machine method, the | |
2600 | * it can call this function. | |
2601 | */ | |
2602 | void ftrace_run_stop_machine(int command) | |
2603 | { | |
2604 | stop_machine(__ftrace_modify_code, &command, NULL); | |
2605 | } | |
2606 | ||
2607 | /** | |
2608 | * arch_ftrace_update_code, modify the code to trace or not trace | |
2609 | * @command: The command that needs to be done | |
2610 | * | |
2611 | * Archs can override this function if it does not need to | |
2612 | * run stop_machine() to modify code. | |
2613 | */ | |
2614 | void __weak arch_ftrace_update_code(int command) | |
2615 | { | |
2616 | ftrace_run_stop_machine(command); | |
2617 | } | |
2618 | ||
e309b41d | 2619 | static void ftrace_run_update_code(int command) |
3d083395 | 2620 | { |
000ab691 SR |
2621 | int ret; |
2622 | ||
2623 | ret = ftrace_arch_code_modify_prepare(); | |
2624 | FTRACE_WARN_ON(ret); | |
2625 | if (ret) | |
2626 | return; | |
2627 | ||
c88fd863 SR |
2628 | /* |
2629 | * By default we use stop_machine() to modify the code. | |
2630 | * But archs can do what ever they want as long as it | |
2631 | * is safe. The stop_machine() is the safest, but also | |
2632 | * produces the most overhead. | |
2633 | */ | |
2634 | arch_ftrace_update_code(command); | |
2635 | ||
000ab691 SR |
2636 | ret = ftrace_arch_code_modify_post_process(); |
2637 | FTRACE_WARN_ON(ret); | |
3d083395 SR |
2638 | } |
2639 | ||
8252ecf3 | 2640 | static void ftrace_run_modify_code(struct ftrace_ops *ops, int command, |
7485058e | 2641 | struct ftrace_ops_hash *old_hash) |
e1effa01 SRRH |
2642 | { |
2643 | ops->flags |= FTRACE_OPS_FL_MODIFYING; | |
7485058e SRRH |
2644 | ops->old_hash.filter_hash = old_hash->filter_hash; |
2645 | ops->old_hash.notrace_hash = old_hash->notrace_hash; | |
e1effa01 | 2646 | ftrace_run_update_code(command); |
8252ecf3 | 2647 | ops->old_hash.filter_hash = NULL; |
7485058e | 2648 | ops->old_hash.notrace_hash = NULL; |
e1effa01 SRRH |
2649 | ops->flags &= ~FTRACE_OPS_FL_MODIFYING; |
2650 | } | |
2651 | ||
d61f82d0 | 2652 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 2653 | static int ftrace_start_up; |
df4fc315 | 2654 | |
12cce594 SRRH |
2655 | void __weak arch_ftrace_trampoline_free(struct ftrace_ops *ops) |
2656 | { | |
2657 | } | |
2658 | ||
ba27f2bc | 2659 | static void per_cpu_ops_free(struct ftrace_ops *ops) |
db0fbadc JS |
2660 | { |
2661 | free_percpu(ops->disabled); | |
2662 | } | |
2663 | ||
df4fc315 SR |
2664 | static void ftrace_startup_enable(int command) |
2665 | { | |
2666 | if (saved_ftrace_func != ftrace_trace_function) { | |
2667 | saved_ftrace_func = ftrace_trace_function; | |
2668 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2669 | } | |
2670 | ||
2671 | if (!command || !ftrace_enabled) | |
2672 | return; | |
2673 | ||
2674 | ftrace_run_update_code(command); | |
2675 | } | |
d61f82d0 | 2676 | |
e1effa01 SRRH |
2677 | static void ftrace_startup_all(int command) |
2678 | { | |
2679 | update_all_ops = true; | |
2680 | ftrace_startup_enable(command); | |
2681 | update_all_ops = false; | |
2682 | } | |
2683 | ||
a1cd6173 | 2684 | static int ftrace_startup(struct ftrace_ops *ops, int command) |
3d083395 | 2685 | { |
8a56d776 | 2686 | int ret; |
b848914c | 2687 | |
4eebcc81 | 2688 | if (unlikely(ftrace_disabled)) |
a1cd6173 | 2689 | return -ENODEV; |
4eebcc81 | 2690 | |
8a56d776 SRRH |
2691 | ret = __register_ftrace_function(ops); |
2692 | if (ret) | |
2693 | return ret; | |
2694 | ||
60a7ecf4 | 2695 | ftrace_start_up++; |
d61f82d0 | 2696 | |
e1effa01 SRRH |
2697 | /* |
2698 | * Note that ftrace probes uses this to start up | |
2699 | * and modify functions it will probe. But we still | |
2700 | * set the ADDING flag for modification, as probes | |
2701 | * do not have trampolines. If they add them in the | |
2702 | * future, then the probes will need to distinguish | |
2703 | * between adding and updating probes. | |
2704 | */ | |
2705 | ops->flags |= FTRACE_OPS_FL_ENABLED | FTRACE_OPS_FL_ADDING; | |
66209a5b | 2706 | |
f8b8be8a MH |
2707 | ret = ftrace_hash_ipmodify_enable(ops); |
2708 | if (ret < 0) { | |
2709 | /* Rollback registration process */ | |
2710 | __unregister_ftrace_function(ops); | |
2711 | ftrace_start_up--; | |
2712 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; | |
2713 | return ret; | |
2714 | } | |
2715 | ||
7f50d06b JO |
2716 | if (ftrace_hash_rec_enable(ops, 1)) |
2717 | command |= FTRACE_UPDATE_CALLS; | |
ed926f9b | 2718 | |
df4fc315 | 2719 | ftrace_startup_enable(command); |
a1cd6173 | 2720 | |
e1effa01 SRRH |
2721 | ops->flags &= ~FTRACE_OPS_FL_ADDING; |
2722 | ||
a1cd6173 | 2723 | return 0; |
3d083395 SR |
2724 | } |
2725 | ||
8a56d776 | 2726 | static int ftrace_shutdown(struct ftrace_ops *ops, int command) |
3d083395 | 2727 | { |
8a56d776 | 2728 | int ret; |
b848914c | 2729 | |
4eebcc81 | 2730 | if (unlikely(ftrace_disabled)) |
8a56d776 SRRH |
2731 | return -ENODEV; |
2732 | ||
2733 | ret = __unregister_ftrace_function(ops); | |
2734 | if (ret) | |
2735 | return ret; | |
4eebcc81 | 2736 | |
60a7ecf4 | 2737 | ftrace_start_up--; |
9ea1a153 FW |
2738 | /* |
2739 | * Just warn in case of unbalance, no need to kill ftrace, it's not | |
2740 | * critical but the ftrace_call callers may be never nopped again after | |
2741 | * further ftrace uses. | |
2742 | */ | |
2743 | WARN_ON_ONCE(ftrace_start_up < 0); | |
2744 | ||
f8b8be8a MH |
2745 | /* Disabling ipmodify never fails */ |
2746 | ftrace_hash_ipmodify_disable(ops); | |
ed926f9b | 2747 | |
7f50d06b JO |
2748 | if (ftrace_hash_rec_disable(ops, 1)) |
2749 | command |= FTRACE_UPDATE_CALLS; | |
b848914c | 2750 | |
7f50d06b | 2751 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; |
3d083395 | 2752 | |
d61f82d0 SR |
2753 | if (saved_ftrace_func != ftrace_trace_function) { |
2754 | saved_ftrace_func = ftrace_trace_function; | |
2755 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2756 | } | |
3d083395 | 2757 | |
a4c35ed2 SRRH |
2758 | if (!command || !ftrace_enabled) { |
2759 | /* | |
ba27f2bc | 2760 | * If these are per_cpu ops, they still need their |
a4c35ed2 SRRH |
2761 | * per_cpu field freed. Since, function tracing is |
2762 | * not currently active, we can just free them | |
2763 | * without synchronizing all CPUs. | |
2764 | */ | |
ba27f2bc SRRH |
2765 | if (ops->flags & FTRACE_OPS_FL_PER_CPU) |
2766 | per_cpu_ops_free(ops); | |
8a56d776 | 2767 | return 0; |
a4c35ed2 | 2768 | } |
d61f82d0 | 2769 | |
79922b80 SRRH |
2770 | /* |
2771 | * If the ops uses a trampoline, then it needs to be | |
2772 | * tested first on update. | |
2773 | */ | |
e1effa01 | 2774 | ops->flags |= FTRACE_OPS_FL_REMOVING; |
79922b80 SRRH |
2775 | removed_ops = ops; |
2776 | ||
fef5aeee SRRH |
2777 | /* The trampoline logic checks the old hashes */ |
2778 | ops->old_hash.filter_hash = ops->func_hash->filter_hash; | |
2779 | ops->old_hash.notrace_hash = ops->func_hash->notrace_hash; | |
2780 | ||
d61f82d0 | 2781 | ftrace_run_update_code(command); |
a4c35ed2 | 2782 | |
84bde62c SRRH |
2783 | /* |
2784 | * If there's no more ops registered with ftrace, run a | |
2785 | * sanity check to make sure all rec flags are cleared. | |
2786 | */ | |
2787 | if (ftrace_ops_list == &ftrace_list_end) { | |
2788 | struct ftrace_page *pg; | |
2789 | struct dyn_ftrace *rec; | |
2790 | ||
2791 | do_for_each_ftrace_rec(pg, rec) { | |
977c1f9c | 2792 | if (FTRACE_WARN_ON_ONCE(rec->flags & ~FTRACE_FL_DISABLED)) |
84bde62c SRRH |
2793 | pr_warn(" %pS flags:%lx\n", |
2794 | (void *)rec->ip, rec->flags); | |
2795 | } while_for_each_ftrace_rec(); | |
2796 | } | |
2797 | ||
fef5aeee SRRH |
2798 | ops->old_hash.filter_hash = NULL; |
2799 | ops->old_hash.notrace_hash = NULL; | |
2800 | ||
2801 | removed_ops = NULL; | |
e1effa01 | 2802 | ops->flags &= ~FTRACE_OPS_FL_REMOVING; |
79922b80 | 2803 | |
a4c35ed2 SRRH |
2804 | /* |
2805 | * Dynamic ops may be freed, we must make sure that all | |
2806 | * callers are done before leaving this function. | |
ba27f2bc | 2807 | * The same goes for freeing the per_cpu data of the per_cpu |
a4c35ed2 | 2808 | * ops. |
a4c35ed2 | 2809 | */ |
ba27f2bc | 2810 | if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_PER_CPU)) { |
0598e4f0 SRV |
2811 | /* |
2812 | * We need to do a hard force of sched synchronization. | |
2813 | * This is because we use preempt_disable() to do RCU, but | |
2814 | * the function tracers can be called where RCU is not watching | |
2815 | * (like before user_exit()). We can not rely on the RCU | |
2816 | * infrastructure to do the synchronization, thus we must do it | |
2817 | * ourselves. | |
2818 | */ | |
a4c35ed2 SRRH |
2819 | schedule_on_each_cpu(ftrace_sync); |
2820 | ||
0598e4f0 SRV |
2821 | /* |
2822 | * When the kernel is preeptive, tasks can be preempted | |
2823 | * while on a ftrace trampoline. Just scheduling a task on | |
2824 | * a CPU is not good enough to flush them. Calling | |
2825 | * synchornize_rcu_tasks() will wait for those tasks to | |
2826 | * execute and either schedule voluntarily or enter user space. | |
2827 | */ | |
2828 | if (IS_ENABLED(CONFIG_PREEMPT)) | |
2829 | synchronize_rcu_tasks(); | |
2830 | ||
12cce594 SRRH |
2831 | arch_ftrace_trampoline_free(ops); |
2832 | ||
ba27f2bc SRRH |
2833 | if (ops->flags & FTRACE_OPS_FL_PER_CPU) |
2834 | per_cpu_ops_free(ops); | |
a4c35ed2 SRRH |
2835 | } |
2836 | ||
8a56d776 | 2837 | return 0; |
3d083395 SR |
2838 | } |
2839 | ||
e309b41d | 2840 | static void ftrace_startup_sysctl(void) |
b0fc494f | 2841 | { |
1619dc3f PA |
2842 | int command; |
2843 | ||
4eebcc81 SR |
2844 | if (unlikely(ftrace_disabled)) |
2845 | return; | |
2846 | ||
d61f82d0 SR |
2847 | /* Force update next time */ |
2848 | saved_ftrace_func = NULL; | |
60a7ecf4 | 2849 | /* ftrace_start_up is true if we want ftrace running */ |
1619dc3f PA |
2850 | if (ftrace_start_up) { |
2851 | command = FTRACE_UPDATE_CALLS; | |
2852 | if (ftrace_graph_active) | |
2853 | command |= FTRACE_START_FUNC_RET; | |
524a3868 | 2854 | ftrace_startup_enable(command); |
1619dc3f | 2855 | } |
b0fc494f SR |
2856 | } |
2857 | ||
e309b41d | 2858 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 2859 | { |
1619dc3f PA |
2860 | int command; |
2861 | ||
4eebcc81 SR |
2862 | if (unlikely(ftrace_disabled)) |
2863 | return; | |
2864 | ||
60a7ecf4 | 2865 | /* ftrace_start_up is true if ftrace is running */ |
1619dc3f PA |
2866 | if (ftrace_start_up) { |
2867 | command = FTRACE_DISABLE_CALLS; | |
2868 | if (ftrace_graph_active) | |
2869 | command |= FTRACE_STOP_FUNC_RET; | |
2870 | ftrace_run_update_code(command); | |
2871 | } | |
b0fc494f SR |
2872 | } |
2873 | ||
a5a1d1c2 | 2874 | static u64 ftrace_update_time; |
3d083395 SR |
2875 | unsigned long ftrace_update_tot_cnt; |
2876 | ||
8c4f3c3f | 2877 | static inline int ops_traces_mod(struct ftrace_ops *ops) |
f7bc8b61 | 2878 | { |
8c4f3c3f SRRH |
2879 | /* |
2880 | * Filter_hash being empty will default to trace module. | |
2881 | * But notrace hash requires a test of individual module functions. | |
2882 | */ | |
33b7f99c SRRH |
2883 | return ftrace_hash_empty(ops->func_hash->filter_hash) && |
2884 | ftrace_hash_empty(ops->func_hash->notrace_hash); | |
8c4f3c3f SRRH |
2885 | } |
2886 | ||
2887 | /* | |
2888 | * Check if the current ops references the record. | |
2889 | * | |
2890 | * If the ops traces all functions, then it was already accounted for. | |
2891 | * If the ops does not trace the current record function, skip it. | |
2892 | * If the ops ignores the function via notrace filter, skip it. | |
2893 | */ | |
2894 | static inline bool | |
2895 | ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec) | |
2896 | { | |
2897 | /* If ops isn't enabled, ignore it */ | |
2898 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
2899 | return 0; | |
2900 | ||
b7ffffbb | 2901 | /* If ops traces all then it includes this function */ |
8c4f3c3f | 2902 | if (ops_traces_mod(ops)) |
b7ffffbb | 2903 | return 1; |
8c4f3c3f SRRH |
2904 | |
2905 | /* The function must be in the filter */ | |
33b7f99c | 2906 | if (!ftrace_hash_empty(ops->func_hash->filter_hash) && |
2b2c279c | 2907 | !__ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip)) |
8c4f3c3f | 2908 | return 0; |
f7bc8b61 | 2909 | |
8c4f3c3f | 2910 | /* If in notrace hash, we ignore it too */ |
33b7f99c | 2911 | if (ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip)) |
8c4f3c3f SRRH |
2912 | return 0; |
2913 | ||
2914 | return 1; | |
2915 | } | |
2916 | ||
1dc43cf0 | 2917 | static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs) |
3d083395 | 2918 | { |
85ae32ae | 2919 | struct ftrace_page *pg; |
e94142a6 | 2920 | struct dyn_ftrace *p; |
a5a1d1c2 | 2921 | u64 start, stop; |
1dc43cf0 | 2922 | unsigned long update_cnt = 0; |
b7ffffbb | 2923 | unsigned long rec_flags = 0; |
85ae32ae | 2924 | int i; |
f7bc8b61 | 2925 | |
b7ffffbb SRRH |
2926 | start = ftrace_now(raw_smp_processor_id()); |
2927 | ||
f7bc8b61 | 2928 | /* |
b7ffffbb SRRH |
2929 | * When a module is loaded, this function is called to convert |
2930 | * the calls to mcount in its text to nops, and also to create | |
2931 | * an entry in the ftrace data. Now, if ftrace is activated | |
2932 | * after this call, but before the module sets its text to | |
2933 | * read-only, the modification of enabling ftrace can fail if | |
2934 | * the read-only is done while ftrace is converting the calls. | |
2935 | * To prevent this, the module's records are set as disabled | |
2936 | * and will be enabled after the call to set the module's text | |
2937 | * to read-only. | |
f7bc8b61 | 2938 | */ |
b7ffffbb SRRH |
2939 | if (mod) |
2940 | rec_flags |= FTRACE_FL_DISABLED; | |
3d083395 | 2941 | |
1dc43cf0 | 2942 | for (pg = new_pgs; pg; pg = pg->next) { |
3d083395 | 2943 | |
85ae32ae | 2944 | for (i = 0; i < pg->index; i++) { |
8c4f3c3f | 2945 | |
85ae32ae SR |
2946 | /* If something went wrong, bail without enabling anything */ |
2947 | if (unlikely(ftrace_disabled)) | |
2948 | return -1; | |
f22f9a89 | 2949 | |
85ae32ae | 2950 | p = &pg->records[i]; |
b7ffffbb | 2951 | p->flags = rec_flags; |
f22f9a89 | 2952 | |
85ae32ae SR |
2953 | /* |
2954 | * Do the initial record conversion from mcount jump | |
2955 | * to the NOP instructions. | |
2956 | */ | |
2957 | if (!ftrace_code_disable(mod, p)) | |
2958 | break; | |
5cb084bb | 2959 | |
1dc43cf0 | 2960 | update_cnt++; |
5cb084bb | 2961 | } |
3d083395 SR |
2962 | } |
2963 | ||
750ed1a4 | 2964 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 | 2965 | ftrace_update_time = stop - start; |
1dc43cf0 | 2966 | ftrace_update_tot_cnt += update_cnt; |
3d083395 | 2967 | |
16444a8a ACM |
2968 | return 0; |
2969 | } | |
2970 | ||
a7900875 | 2971 | static int ftrace_allocate_records(struct ftrace_page *pg, int count) |
3c1720f0 | 2972 | { |
a7900875 | 2973 | int order; |
3c1720f0 | 2974 | int cnt; |
3c1720f0 | 2975 | |
a7900875 SR |
2976 | if (WARN_ON(!count)) |
2977 | return -EINVAL; | |
2978 | ||
2979 | order = get_count_order(DIV_ROUND_UP(count, ENTRIES_PER_PAGE)); | |
3c1720f0 SR |
2980 | |
2981 | /* | |
a7900875 SR |
2982 | * We want to fill as much as possible. No more than a page |
2983 | * may be empty. | |
3c1720f0 | 2984 | */ |
a7900875 SR |
2985 | while ((PAGE_SIZE << order) / ENTRY_SIZE >= count + ENTRIES_PER_PAGE) |
2986 | order--; | |
3c1720f0 | 2987 | |
a7900875 SR |
2988 | again: |
2989 | pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); | |
3c1720f0 | 2990 | |
a7900875 SR |
2991 | if (!pg->records) { |
2992 | /* if we can't allocate this size, try something smaller */ | |
2993 | if (!order) | |
2994 | return -ENOMEM; | |
2995 | order >>= 1; | |
2996 | goto again; | |
2997 | } | |
3c1720f0 | 2998 | |
a7900875 SR |
2999 | cnt = (PAGE_SIZE << order) / ENTRY_SIZE; |
3000 | pg->size = cnt; | |
3c1720f0 | 3001 | |
a7900875 SR |
3002 | if (cnt > count) |
3003 | cnt = count; | |
3004 | ||
3005 | return cnt; | |
3006 | } | |
3007 | ||
3008 | static struct ftrace_page * | |
3009 | ftrace_allocate_pages(unsigned long num_to_init) | |
3010 | { | |
3011 | struct ftrace_page *start_pg; | |
3012 | struct ftrace_page *pg; | |
3013 | int order; | |
3014 | int cnt; | |
3015 | ||
3016 | if (!num_to_init) | |
3017 | return 0; | |
3018 | ||
3019 | start_pg = pg = kzalloc(sizeof(*pg), GFP_KERNEL); | |
3020 | if (!pg) | |
3021 | return NULL; | |
3022 | ||
3023 | /* | |
3024 | * Try to allocate as much as possible in one continues | |
3025 | * location that fills in all of the space. We want to | |
3026 | * waste as little space as possible. | |
3027 | */ | |
3028 | for (;;) { | |
3029 | cnt = ftrace_allocate_records(pg, num_to_init); | |
3030 | if (cnt < 0) | |
3031 | goto free_pages; | |
3032 | ||
3033 | num_to_init -= cnt; | |
3034 | if (!num_to_init) | |
3c1720f0 SR |
3035 | break; |
3036 | ||
a7900875 SR |
3037 | pg->next = kzalloc(sizeof(*pg), GFP_KERNEL); |
3038 | if (!pg->next) | |
3039 | goto free_pages; | |
3040 | ||
3c1720f0 SR |
3041 | pg = pg->next; |
3042 | } | |
3043 | ||
a7900875 SR |
3044 | return start_pg; |
3045 | ||
3046 | free_pages: | |
1f61be00 NK |
3047 | pg = start_pg; |
3048 | while (pg) { | |
a7900875 SR |
3049 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); |
3050 | free_pages((unsigned long)pg->records, order); | |
3051 | start_pg = pg->next; | |
3052 | kfree(pg); | |
3053 | pg = start_pg; | |
3054 | } | |
3055 | pr_info("ftrace: FAILED to allocate memory for functions\n"); | |
3056 | return NULL; | |
3057 | } | |
3058 | ||
5072c59f SR |
3059 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ |
3060 | ||
3061 | struct ftrace_iterator { | |
98c4fd04 | 3062 | loff_t pos; |
4aeb6967 SR |
3063 | loff_t func_pos; |
3064 | struct ftrace_page *pg; | |
3065 | struct dyn_ftrace *func; | |
3066 | struct ftrace_func_probe *probe; | |
eee8ded1 | 3067 | struct ftrace_func_entry *probe_entry; |
4aeb6967 | 3068 | struct trace_parser parser; |
1cf41dd7 | 3069 | struct ftrace_hash *hash; |
33dc9b12 | 3070 | struct ftrace_ops *ops; |
eee8ded1 | 3071 | int pidx; |
4aeb6967 SR |
3072 | int idx; |
3073 | unsigned flags; | |
5072c59f SR |
3074 | }; |
3075 | ||
8fc0c701 | 3076 | static void * |
eee8ded1 | 3077 | t_probe_next(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
3078 | { |
3079 | struct ftrace_iterator *iter = m->private; | |
d2afd57a | 3080 | struct trace_array *tr = iter->ops->private; |
04ec7bb6 | 3081 | struct list_head *func_probes; |
eee8ded1 SRV |
3082 | struct ftrace_hash *hash; |
3083 | struct list_head *next; | |
4aeb6967 | 3084 | struct hlist_node *hnd = NULL; |
8fc0c701 | 3085 | struct hlist_head *hhd; |
eee8ded1 | 3086 | int size; |
8fc0c701 | 3087 | |
8fc0c701 | 3088 | (*pos)++; |
98c4fd04 | 3089 | iter->pos = *pos; |
8fc0c701 | 3090 | |
04ec7bb6 | 3091 | if (!tr) |
8fc0c701 SR |
3092 | return NULL; |
3093 | ||
04ec7bb6 SRV |
3094 | func_probes = &tr->func_probes; |
3095 | if (list_empty(func_probes)) | |
8fc0c701 SR |
3096 | return NULL; |
3097 | ||
eee8ded1 | 3098 | if (!iter->probe) { |
04ec7bb6 | 3099 | next = func_probes->next; |
7b60f3d8 | 3100 | iter->probe = list_entry(next, struct ftrace_func_probe, list); |
eee8ded1 SRV |
3101 | } |
3102 | ||
3103 | if (iter->probe_entry) | |
3104 | hnd = &iter->probe_entry->hlist; | |
3105 | ||
3106 | hash = iter->probe->ops.func_hash->filter_hash; | |
3107 | size = 1 << hash->size_bits; | |
3108 | ||
3109 | retry: | |
3110 | if (iter->pidx >= size) { | |
04ec7bb6 | 3111 | if (iter->probe->list.next == func_probes) |
eee8ded1 SRV |
3112 | return NULL; |
3113 | next = iter->probe->list.next; | |
7b60f3d8 | 3114 | iter->probe = list_entry(next, struct ftrace_func_probe, list); |
eee8ded1 SRV |
3115 | hash = iter->probe->ops.func_hash->filter_hash; |
3116 | size = 1 << hash->size_bits; | |
3117 | iter->pidx = 0; | |
3118 | } | |
3119 | ||
3120 | hhd = &hash->buckets[iter->pidx]; | |
8fc0c701 SR |
3121 | |
3122 | if (hlist_empty(hhd)) { | |
eee8ded1 | 3123 | iter->pidx++; |
8fc0c701 SR |
3124 | hnd = NULL; |
3125 | goto retry; | |
3126 | } | |
3127 | ||
3128 | if (!hnd) | |
3129 | hnd = hhd->first; | |
3130 | else { | |
3131 | hnd = hnd->next; | |
3132 | if (!hnd) { | |
eee8ded1 | 3133 | iter->pidx++; |
8fc0c701 SR |
3134 | goto retry; |
3135 | } | |
3136 | } | |
3137 | ||
4aeb6967 SR |
3138 | if (WARN_ON_ONCE(!hnd)) |
3139 | return NULL; | |
3140 | ||
eee8ded1 | 3141 | iter->probe_entry = hlist_entry(hnd, struct ftrace_func_entry, hlist); |
4aeb6967 SR |
3142 | |
3143 | return iter; | |
8fc0c701 SR |
3144 | } |
3145 | ||
eee8ded1 | 3146 | static void *t_probe_start(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
3147 | { |
3148 | struct ftrace_iterator *iter = m->private; | |
3149 | void *p = NULL; | |
d82d6244 LZ |
3150 | loff_t l; |
3151 | ||
eee8ded1 | 3152 | if (!(iter->flags & FTRACE_ITER_DO_PROBES)) |
69a3083c SR |
3153 | return NULL; |
3154 | ||
2bccfffd SR |
3155 | if (iter->func_pos > *pos) |
3156 | return NULL; | |
8fc0c701 | 3157 | |
eee8ded1 SRV |
3158 | iter->probe = NULL; |
3159 | iter->probe_entry = NULL; | |
3160 | iter->pidx = 0; | |
2bccfffd | 3161 | for (l = 0; l <= (*pos - iter->func_pos); ) { |
eee8ded1 | 3162 | p = t_probe_next(m, &l); |
d82d6244 LZ |
3163 | if (!p) |
3164 | break; | |
3165 | } | |
4aeb6967 SR |
3166 | if (!p) |
3167 | return NULL; | |
3168 | ||
98c4fd04 | 3169 | /* Only set this if we have an item */ |
eee8ded1 | 3170 | iter->flags |= FTRACE_ITER_PROBE; |
98c4fd04 | 3171 | |
4aeb6967 | 3172 | return iter; |
8fc0c701 SR |
3173 | } |
3174 | ||
4aeb6967 | 3175 | static int |
eee8ded1 | 3176 | t_probe_show(struct seq_file *m, struct ftrace_iterator *iter) |
8fc0c701 | 3177 | { |
eee8ded1 | 3178 | struct ftrace_func_entry *probe_entry; |
7b60f3d8 SRV |
3179 | struct ftrace_probe_ops *probe_ops; |
3180 | struct ftrace_func_probe *probe; | |
8fc0c701 | 3181 | |
eee8ded1 SRV |
3182 | probe = iter->probe; |
3183 | probe_entry = iter->probe_entry; | |
8fc0c701 | 3184 | |
eee8ded1 | 3185 | if (WARN_ON_ONCE(!probe || !probe_entry)) |
4aeb6967 | 3186 | return -EIO; |
8fc0c701 | 3187 | |
7b60f3d8 | 3188 | probe_ops = probe->probe_ops; |
809dcf29 | 3189 | |
7b60f3d8 | 3190 | if (probe_ops->print) |
6e444319 | 3191 | return probe_ops->print(m, probe_entry->ip, probe_ops, probe->data); |
8fc0c701 | 3192 | |
7b60f3d8 SRV |
3193 | seq_printf(m, "%ps:%ps\n", (void *)probe_entry->ip, |
3194 | (void *)probe_ops->func); | |
8fc0c701 SR |
3195 | |
3196 | return 0; | |
3197 | } | |
3198 | ||
e309b41d | 3199 | static void * |
5bd84629 | 3200 | t_func_next(struct seq_file *m, loff_t *pos) |
5072c59f SR |
3201 | { |
3202 | struct ftrace_iterator *iter = m->private; | |
3203 | struct dyn_ftrace *rec = NULL; | |
3204 | ||
3205 | (*pos)++; | |
0c75a3ed | 3206 | |
5072c59f SR |
3207 | retry: |
3208 | if (iter->idx >= iter->pg->index) { | |
3209 | if (iter->pg->next) { | |
3210 | iter->pg = iter->pg->next; | |
3211 | iter->idx = 0; | |
3212 | goto retry; | |
3213 | } | |
3214 | } else { | |
3215 | rec = &iter->pg->records[iter->idx++]; | |
c20489da SRV |
3216 | if (((iter->flags & (FTRACE_ITER_FILTER | FTRACE_ITER_NOTRACE)) && |
3217 | !ftrace_lookup_ip(iter->hash, rec->ip)) || | |
647bcd03 SR |
3218 | |
3219 | ((iter->flags & FTRACE_ITER_ENABLED) && | |
23ea9c4d | 3220 | !(rec->flags & FTRACE_FL_ENABLED))) { |
647bcd03 | 3221 | |
5072c59f SR |
3222 | rec = NULL; |
3223 | goto retry; | |
3224 | } | |
3225 | } | |
3226 | ||
4aeb6967 | 3227 | if (!rec) |
5bd84629 | 3228 | return NULL; |
4aeb6967 | 3229 | |
5bd84629 | 3230 | iter->pos = iter->func_pos = *pos; |
4aeb6967 SR |
3231 | iter->func = rec; |
3232 | ||
3233 | return iter; | |
5072c59f SR |
3234 | } |
3235 | ||
5bd84629 SRV |
3236 | static void * |
3237 | t_next(struct seq_file *m, void *v, loff_t *pos) | |
3238 | { | |
3239 | struct ftrace_iterator *iter = m->private; | |
fcdc7125 | 3240 | loff_t l = *pos; /* t_hash_start() must use original pos */ |
5bd84629 SRV |
3241 | void *ret; |
3242 | ||
3243 | if (unlikely(ftrace_disabled)) | |
3244 | return NULL; | |
3245 | ||
eee8ded1 SRV |
3246 | if (iter->flags & FTRACE_ITER_PROBE) |
3247 | return t_probe_next(m, pos); | |
5bd84629 SRV |
3248 | |
3249 | if (iter->flags & FTRACE_ITER_PRINTALL) { | |
eee8ded1 | 3250 | /* next must increment pos, and t_probe_start does not */ |
5bd84629 | 3251 | (*pos)++; |
eee8ded1 | 3252 | return t_probe_start(m, &l); |
5bd84629 SRV |
3253 | } |
3254 | ||
3255 | ret = t_func_next(m, pos); | |
3256 | ||
3257 | if (!ret) | |
eee8ded1 | 3258 | return t_probe_start(m, &l); |
5bd84629 SRV |
3259 | |
3260 | return ret; | |
3261 | } | |
3262 | ||
98c4fd04 SR |
3263 | static void reset_iter_read(struct ftrace_iterator *iter) |
3264 | { | |
3265 | iter->pos = 0; | |
3266 | iter->func_pos = 0; | |
eee8ded1 | 3267 | iter->flags &= ~(FTRACE_ITER_PRINTALL | FTRACE_ITER_PROBE); |
5072c59f SR |
3268 | } |
3269 | ||
3270 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3271 | { | |
3272 | struct ftrace_iterator *iter = m->private; | |
3273 | void *p = NULL; | |
694ce0a5 | 3274 | loff_t l; |
5072c59f | 3275 | |
8fc0c701 | 3276 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
3277 | |
3278 | if (unlikely(ftrace_disabled)) | |
3279 | return NULL; | |
3280 | ||
98c4fd04 SR |
3281 | /* |
3282 | * If an lseek was done, then reset and start from beginning. | |
3283 | */ | |
3284 | if (*pos < iter->pos) | |
3285 | reset_iter_read(iter); | |
3286 | ||
0c75a3ed SR |
3287 | /* |
3288 | * For set_ftrace_filter reading, if we have the filter | |
3289 | * off, we can short cut and just print out that all | |
3290 | * functions are enabled. | |
3291 | */ | |
c20489da SRV |
3292 | if ((iter->flags & (FTRACE_ITER_FILTER | FTRACE_ITER_NOTRACE)) && |
3293 | ftrace_hash_empty(iter->hash)) { | |
43ff926a | 3294 | iter->func_pos = 1; /* Account for the message */ |
0c75a3ed | 3295 | if (*pos > 0) |
eee8ded1 | 3296 | return t_probe_start(m, pos); |
0c75a3ed | 3297 | iter->flags |= FTRACE_ITER_PRINTALL; |
df091625 | 3298 | /* reset in case of seek/pread */ |
eee8ded1 | 3299 | iter->flags &= ~FTRACE_ITER_PROBE; |
0c75a3ed SR |
3300 | return iter; |
3301 | } | |
3302 | ||
eee8ded1 SRV |
3303 | if (iter->flags & FTRACE_ITER_PROBE) |
3304 | return t_probe_start(m, pos); | |
8fc0c701 | 3305 | |
98c4fd04 SR |
3306 | /* |
3307 | * Unfortunately, we need to restart at ftrace_pages_start | |
3308 | * every time we let go of the ftrace_mutex. This is because | |
3309 | * those pointers can change without the lock. | |
3310 | */ | |
694ce0a5 LZ |
3311 | iter->pg = ftrace_pages_start; |
3312 | iter->idx = 0; | |
3313 | for (l = 0; l <= *pos; ) { | |
5bd84629 | 3314 | p = t_func_next(m, &l); |
694ce0a5 LZ |
3315 | if (!p) |
3316 | break; | |
50cdaf08 | 3317 | } |
5821e1b7 | 3318 | |
69a3083c | 3319 | if (!p) |
eee8ded1 | 3320 | return t_probe_start(m, pos); |
4aeb6967 SR |
3321 | |
3322 | return iter; | |
5072c59f SR |
3323 | } |
3324 | ||
3325 | static void t_stop(struct seq_file *m, void *p) | |
3326 | { | |
8fc0c701 | 3327 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
3328 | } |
3329 | ||
15d5b02c SRRH |
3330 | void * __weak |
3331 | arch_ftrace_trampoline_func(struct ftrace_ops *ops, struct dyn_ftrace *rec) | |
3332 | { | |
3333 | return NULL; | |
3334 | } | |
3335 | ||
3336 | static void add_trampoline_func(struct seq_file *m, struct ftrace_ops *ops, | |
3337 | struct dyn_ftrace *rec) | |
3338 | { | |
3339 | void *ptr; | |
3340 | ||
3341 | ptr = arch_ftrace_trampoline_func(ops, rec); | |
3342 | if (ptr) | |
3343 | seq_printf(m, " ->%pS", ptr); | |
3344 | } | |
3345 | ||
5072c59f SR |
3346 | static int t_show(struct seq_file *m, void *v) |
3347 | { | |
0c75a3ed | 3348 | struct ftrace_iterator *iter = m->private; |
4aeb6967 | 3349 | struct dyn_ftrace *rec; |
5072c59f | 3350 | |
eee8ded1 SRV |
3351 | if (iter->flags & FTRACE_ITER_PROBE) |
3352 | return t_probe_show(m, iter); | |
8fc0c701 | 3353 | |
0c75a3ed | 3354 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
8c006cf7 | 3355 | if (iter->flags & FTRACE_ITER_NOTRACE) |
fa6f0cc7 | 3356 | seq_puts(m, "#### no functions disabled ####\n"); |
8c006cf7 | 3357 | else |
fa6f0cc7 | 3358 | seq_puts(m, "#### all functions enabled ####\n"); |
0c75a3ed SR |
3359 | return 0; |
3360 | } | |
3361 | ||
4aeb6967 SR |
3362 | rec = iter->func; |
3363 | ||
5072c59f SR |
3364 | if (!rec) |
3365 | return 0; | |
3366 | ||
647bcd03 | 3367 | seq_printf(m, "%ps", (void *)rec->ip); |
9674b2fa | 3368 | if (iter->flags & FTRACE_ITER_ENABLED) { |
030f4e1c | 3369 | struct ftrace_ops *ops; |
15d5b02c | 3370 | |
f8b8be8a | 3371 | seq_printf(m, " (%ld)%s%s", |
0376bde1 | 3372 | ftrace_rec_count(rec), |
f8b8be8a MH |
3373 | rec->flags & FTRACE_FL_REGS ? " R" : " ", |
3374 | rec->flags & FTRACE_FL_IPMODIFY ? " I" : " "); | |
9674b2fa | 3375 | if (rec->flags & FTRACE_FL_TRAMP_EN) { |
5fecaa04 | 3376 | ops = ftrace_find_tramp_ops_any(rec); |
39daa7b9 SRRH |
3377 | if (ops) { |
3378 | do { | |
3379 | seq_printf(m, "\ttramp: %pS (%pS)", | |
3380 | (void *)ops->trampoline, | |
3381 | (void *)ops->func); | |
030f4e1c | 3382 | add_trampoline_func(m, ops, rec); |
39daa7b9 SRRH |
3383 | ops = ftrace_find_tramp_ops_next(rec, ops); |
3384 | } while (ops); | |
3385 | } else | |
fa6f0cc7 | 3386 | seq_puts(m, "\ttramp: ERROR!"); |
030f4e1c SRRH |
3387 | } else { |
3388 | add_trampoline_func(m, NULL, rec); | |
9674b2fa SRRH |
3389 | } |
3390 | } | |
3391 | ||
fa6f0cc7 | 3392 | seq_putc(m, '\n'); |
5072c59f SR |
3393 | |
3394 | return 0; | |
3395 | } | |
3396 | ||
88e9d34c | 3397 | static const struct seq_operations show_ftrace_seq_ops = { |
5072c59f SR |
3398 | .start = t_start, |
3399 | .next = t_next, | |
3400 | .stop = t_stop, | |
3401 | .show = t_show, | |
3402 | }; | |
3403 | ||
e309b41d | 3404 | static int |
5072c59f SR |
3405 | ftrace_avail_open(struct inode *inode, struct file *file) |
3406 | { | |
3407 | struct ftrace_iterator *iter; | |
5072c59f | 3408 | |
4eebcc81 SR |
3409 | if (unlikely(ftrace_disabled)) |
3410 | return -ENODEV; | |
3411 | ||
50e18b94 | 3412 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
c1bc5919 SRV |
3413 | if (!iter) |
3414 | return -ENOMEM; | |
5072c59f | 3415 | |
c1bc5919 SRV |
3416 | iter->pg = ftrace_pages_start; |
3417 | iter->ops = &global_ops; | |
3418 | ||
3419 | return 0; | |
5072c59f SR |
3420 | } |
3421 | ||
647bcd03 SR |
3422 | static int |
3423 | ftrace_enabled_open(struct inode *inode, struct file *file) | |
3424 | { | |
3425 | struct ftrace_iterator *iter; | |
647bcd03 | 3426 | |
50e18b94 | 3427 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
c1bc5919 SRV |
3428 | if (!iter) |
3429 | return -ENOMEM; | |
647bcd03 | 3430 | |
c1bc5919 SRV |
3431 | iter->pg = ftrace_pages_start; |
3432 | iter->flags = FTRACE_ITER_ENABLED; | |
3433 | iter->ops = &global_ops; | |
3434 | ||
3435 | return 0; | |
647bcd03 SR |
3436 | } |
3437 | ||
fc13cb0c SR |
3438 | /** |
3439 | * ftrace_regex_open - initialize function tracer filter files | |
3440 | * @ops: The ftrace_ops that hold the hash filters | |
3441 | * @flag: The type of filter to process | |
3442 | * @inode: The inode, usually passed in to your open routine | |
3443 | * @file: The file, usually passed in to your open routine | |
3444 | * | |
3445 | * ftrace_regex_open() initializes the filter files for the | |
3446 | * @ops. Depending on @flag it may process the filter hash or | |
3447 | * the notrace hash of @ops. With this called from the open | |
3448 | * routine, you can use ftrace_filter_write() for the write | |
3449 | * routine if @flag has FTRACE_ITER_FILTER set, or | |
3450 | * ftrace_notrace_write() if @flag has FTRACE_ITER_NOTRACE set. | |
098c879e | 3451 | * tracing_lseek() should be used as the lseek routine, and |
fc13cb0c SR |
3452 | * release must call ftrace_regex_release(). |
3453 | */ | |
3454 | int | |
f45948e8 | 3455 | ftrace_regex_open(struct ftrace_ops *ops, int flag, |
1cf41dd7 | 3456 | struct inode *inode, struct file *file) |
5072c59f SR |
3457 | { |
3458 | struct ftrace_iterator *iter; | |
f45948e8 | 3459 | struct ftrace_hash *hash; |
5072c59f SR |
3460 | int ret = 0; |
3461 | ||
f04f24fb MH |
3462 | ftrace_ops_init(ops); |
3463 | ||
4eebcc81 SR |
3464 | if (unlikely(ftrace_disabled)) |
3465 | return -ENODEV; | |
3466 | ||
5072c59f SR |
3467 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
3468 | if (!iter) | |
3469 | return -ENOMEM; | |
3470 | ||
689fd8b6 | 3471 | if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) { |
3472 | kfree(iter); | |
3473 | return -ENOMEM; | |
3474 | } | |
3475 | ||
3f2367ba MH |
3476 | iter->ops = ops; |
3477 | iter->flags = flag; | |
3478 | ||
33b7f99c | 3479 | mutex_lock(&ops->func_hash->regex_lock); |
3f2367ba | 3480 | |
f45948e8 | 3481 | if (flag & FTRACE_ITER_NOTRACE) |
33b7f99c | 3482 | hash = ops->func_hash->notrace_hash; |
f45948e8 | 3483 | else |
33b7f99c | 3484 | hash = ops->func_hash->filter_hash; |
f45948e8 | 3485 | |
33dc9b12 | 3486 | if (file->f_mode & FMODE_WRITE) { |
ef2fbe16 NK |
3487 | const int size_bits = FTRACE_HASH_DEFAULT_BITS; |
3488 | ||
3489 | if (file->f_flags & O_TRUNC) | |
3490 | iter->hash = alloc_ftrace_hash(size_bits); | |
3491 | else | |
3492 | iter->hash = alloc_and_copy_ftrace_hash(size_bits, hash); | |
3493 | ||
33dc9b12 SR |
3494 | if (!iter->hash) { |
3495 | trace_parser_put(&iter->parser); | |
3496 | kfree(iter); | |
3f2367ba MH |
3497 | ret = -ENOMEM; |
3498 | goto out_unlock; | |
33dc9b12 | 3499 | } |
c20489da SRV |
3500 | } else |
3501 | iter->hash = hash; | |
1cf41dd7 | 3502 | |
5072c59f SR |
3503 | if (file->f_mode & FMODE_READ) { |
3504 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
3505 | |
3506 | ret = seq_open(file, &show_ftrace_seq_ops); | |
3507 | if (!ret) { | |
3508 | struct seq_file *m = file->private_data; | |
3509 | m->private = iter; | |
79fe249c | 3510 | } else { |
33dc9b12 SR |
3511 | /* Failed */ |
3512 | free_ftrace_hash(iter->hash); | |
79fe249c | 3513 | trace_parser_put(&iter->parser); |
5072c59f | 3514 | kfree(iter); |
79fe249c | 3515 | } |
5072c59f SR |
3516 | } else |
3517 | file->private_data = iter; | |
3f2367ba MH |
3518 | |
3519 | out_unlock: | |
33b7f99c | 3520 | mutex_unlock(&ops->func_hash->regex_lock); |
5072c59f SR |
3521 | |
3522 | return ret; | |
3523 | } | |
3524 | ||
41c52c0d SR |
3525 | static int |
3526 | ftrace_filter_open(struct inode *inode, struct file *file) | |
3527 | { | |
e3b3e2e8 SRRH |
3528 | struct ftrace_ops *ops = inode->i_private; |
3529 | ||
3530 | return ftrace_regex_open(ops, | |
eee8ded1 | 3531 | FTRACE_ITER_FILTER | FTRACE_ITER_DO_PROBES, |
69a3083c | 3532 | inode, file); |
41c52c0d SR |
3533 | } |
3534 | ||
3535 | static int | |
3536 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
3537 | { | |
e3b3e2e8 SRRH |
3538 | struct ftrace_ops *ops = inode->i_private; |
3539 | ||
3540 | return ftrace_regex_open(ops, FTRACE_ITER_NOTRACE, | |
1cf41dd7 | 3541 | inode, file); |
41c52c0d SR |
3542 | } |
3543 | ||
3ba00929 DS |
3544 | /* Type for quick search ftrace basic regexes (globs) from filter_parse_regex */ |
3545 | struct ftrace_glob { | |
3546 | char *search; | |
3547 | unsigned len; | |
3548 | int type; | |
3549 | }; | |
3550 | ||
7132e2d6 TJB |
3551 | /* |
3552 | * If symbols in an architecture don't correspond exactly to the user-visible | |
3553 | * name of what they represent, it is possible to define this function to | |
3554 | * perform the necessary adjustments. | |
3555 | */ | |
3556 | char * __weak arch_ftrace_match_adjust(char *str, const char *search) | |
3557 | { | |
3558 | return str; | |
3559 | } | |
3560 | ||
3ba00929 | 3561 | static int ftrace_match(char *str, struct ftrace_glob *g) |
9f4801e3 | 3562 | { |
9f4801e3 | 3563 | int matched = 0; |
751e9983 | 3564 | int slen; |
9f4801e3 | 3565 | |
7132e2d6 TJB |
3566 | str = arch_ftrace_match_adjust(str, g->search); |
3567 | ||
3ba00929 | 3568 | switch (g->type) { |
9f4801e3 | 3569 | case MATCH_FULL: |
3ba00929 | 3570 | if (strcmp(str, g->search) == 0) |
9f4801e3 SR |
3571 | matched = 1; |
3572 | break; | |
3573 | case MATCH_FRONT_ONLY: | |
3ba00929 | 3574 | if (strncmp(str, g->search, g->len) == 0) |
9f4801e3 SR |
3575 | matched = 1; |
3576 | break; | |
3577 | case MATCH_MIDDLE_ONLY: | |
3ba00929 | 3578 | if (strstr(str, g->search)) |
9f4801e3 SR |
3579 | matched = 1; |
3580 | break; | |
3581 | case MATCH_END_ONLY: | |
751e9983 | 3582 | slen = strlen(str); |
3ba00929 DS |
3583 | if (slen >= g->len && |
3584 | memcmp(str + slen - g->len, g->search, g->len) == 0) | |
9f4801e3 SR |
3585 | matched = 1; |
3586 | break; | |
60f1d5e3 MH |
3587 | case MATCH_GLOB: |
3588 | if (glob_match(g->search, str)) | |
3589 | matched = 1; | |
3590 | break; | |
9f4801e3 SR |
3591 | } |
3592 | ||
3593 | return matched; | |
3594 | } | |
3595 | ||
b448c4e3 | 3596 | static int |
f0a3b154 | 3597 | enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int clear_filter) |
996e87be | 3598 | { |
b448c4e3 | 3599 | struct ftrace_func_entry *entry; |
b448c4e3 SR |
3600 | int ret = 0; |
3601 | ||
1cf41dd7 | 3602 | entry = ftrace_lookup_ip(hash, rec->ip); |
f0a3b154 | 3603 | if (clear_filter) { |
1cf41dd7 SR |
3604 | /* Do nothing if it doesn't exist */ |
3605 | if (!entry) | |
3606 | return 0; | |
b448c4e3 | 3607 | |
33dc9b12 | 3608 | free_hash_entry(hash, entry); |
1cf41dd7 SR |
3609 | } else { |
3610 | /* Do nothing if it exists */ | |
3611 | if (entry) | |
3612 | return 0; | |
b448c4e3 | 3613 | |
1cf41dd7 | 3614 | ret = add_hash_entry(hash, rec->ip); |
b448c4e3 SR |
3615 | } |
3616 | return ret; | |
996e87be SR |
3617 | } |
3618 | ||
64e7c440 | 3619 | static int |
0b507e1e DS |
3620 | ftrace_match_record(struct dyn_ftrace *rec, struct ftrace_glob *func_g, |
3621 | struct ftrace_glob *mod_g, int exclude_mod) | |
64e7c440 SR |
3622 | { |
3623 | char str[KSYM_SYMBOL_LEN]; | |
b9df92d2 SR |
3624 | char *modname; |
3625 | ||
3626 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); | |
3627 | ||
0b507e1e DS |
3628 | if (mod_g) { |
3629 | int mod_matches = (modname) ? ftrace_match(modname, mod_g) : 0; | |
3630 | ||
3631 | /* blank module name to match all modules */ | |
3632 | if (!mod_g->len) { | |
3633 | /* blank module globbing: modname xor exclude_mod */ | |
3634 | if ((!exclude_mod) != (!modname)) | |
3635 | goto func_match; | |
3636 | return 0; | |
3637 | } | |
3638 | ||
3639 | /* not matching the module */ | |
3640 | if (!modname || !mod_matches) { | |
3641 | if (exclude_mod) | |
3642 | goto func_match; | |
3643 | else | |
3644 | return 0; | |
3645 | } | |
3646 | ||
31805c90 | 3647 | if (exclude_mod) |
b9df92d2 SR |
3648 | return 0; |
3649 | ||
0b507e1e | 3650 | func_match: |
b9df92d2 | 3651 | /* blank search means to match all funcs in the mod */ |
3ba00929 | 3652 | if (!func_g->len) |
b9df92d2 SR |
3653 | return 1; |
3654 | } | |
64e7c440 | 3655 | |
3ba00929 | 3656 | return ftrace_match(str, func_g); |
64e7c440 SR |
3657 | } |
3658 | ||
1cf41dd7 | 3659 | static int |
3ba00929 | 3660 | match_records(struct ftrace_hash *hash, char *func, int len, char *mod) |
9f4801e3 | 3661 | { |
9f4801e3 SR |
3662 | struct ftrace_page *pg; |
3663 | struct dyn_ftrace *rec; | |
3ba00929 | 3664 | struct ftrace_glob func_g = { .type = MATCH_FULL }; |
0b507e1e DS |
3665 | struct ftrace_glob mod_g = { .type = MATCH_FULL }; |
3666 | struct ftrace_glob *mod_match = (mod) ? &mod_g : NULL; | |
3667 | int exclude_mod = 0; | |
311d16da | 3668 | int found = 0; |
b448c4e3 | 3669 | int ret; |
f0a3b154 | 3670 | int clear_filter; |
9f4801e3 | 3671 | |
0b507e1e | 3672 | if (func) { |
3ba00929 DS |
3673 | func_g.type = filter_parse_regex(func, len, &func_g.search, |
3674 | &clear_filter); | |
3675 | func_g.len = strlen(func_g.search); | |
b9df92d2 | 3676 | } |
9f4801e3 | 3677 | |
0b507e1e DS |
3678 | if (mod) { |
3679 | mod_g.type = filter_parse_regex(mod, strlen(mod), | |
3680 | &mod_g.search, &exclude_mod); | |
3681 | mod_g.len = strlen(mod_g.search); | |
b9df92d2 | 3682 | } |
9f4801e3 | 3683 | |
52baf119 | 3684 | mutex_lock(&ftrace_lock); |
265c831c | 3685 | |
b9df92d2 SR |
3686 | if (unlikely(ftrace_disabled)) |
3687 | goto out_unlock; | |
9f4801e3 | 3688 | |
265c831c | 3689 | do_for_each_ftrace_rec(pg, rec) { |
546fece4 SRRH |
3690 | |
3691 | if (rec->flags & FTRACE_FL_DISABLED) | |
3692 | continue; | |
3693 | ||
0b507e1e | 3694 | if (ftrace_match_record(rec, &func_g, mod_match, exclude_mod)) { |
f0a3b154 | 3695 | ret = enter_record(hash, rec, clear_filter); |
b448c4e3 SR |
3696 | if (ret < 0) { |
3697 | found = ret; | |
3698 | goto out_unlock; | |
3699 | } | |
311d16da | 3700 | found = 1; |
265c831c SR |
3701 | } |
3702 | } while_for_each_ftrace_rec(); | |
b9df92d2 | 3703 | out_unlock: |
52baf119 | 3704 | mutex_unlock(&ftrace_lock); |
311d16da LZ |
3705 | |
3706 | return found; | |
5072c59f SR |
3707 | } |
3708 | ||
64e7c440 | 3709 | static int |
1cf41dd7 | 3710 | ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) |
64e7c440 | 3711 | { |
f0a3b154 | 3712 | return match_records(hash, buff, len, NULL); |
64e7c440 SR |
3713 | } |
3714 | ||
e16b35dd SRV |
3715 | static void ftrace_ops_update_code(struct ftrace_ops *ops, |
3716 | struct ftrace_ops_hash *old_hash) | |
3717 | { | |
3718 | struct ftrace_ops *op; | |
3719 | ||
3720 | if (!ftrace_enabled) | |
3721 | return; | |
3722 | ||
3723 | if (ops->flags & FTRACE_OPS_FL_ENABLED) { | |
3724 | ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS, old_hash); | |
3725 | return; | |
3726 | } | |
3727 | ||
3728 | /* | |
3729 | * If this is the shared global_ops filter, then we need to | |
3730 | * check if there is another ops that shares it, is enabled. | |
3731 | * If so, we still need to run the modify code. | |
3732 | */ | |
3733 | if (ops->func_hash != &global_ops.local_hash) | |
3734 | return; | |
3735 | ||
3736 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
3737 | if (op->func_hash == &global_ops.local_hash && | |
3738 | op->flags & FTRACE_OPS_FL_ENABLED) { | |
3739 | ftrace_run_modify_code(op, FTRACE_UPDATE_CALLS, old_hash); | |
3740 | /* Only need to do this once */ | |
3741 | return; | |
3742 | } | |
3743 | } while_for_each_ftrace_op(op); | |
3744 | } | |
3745 | ||
3746 | static int ftrace_hash_move_and_update_ops(struct ftrace_ops *ops, | |
3747 | struct ftrace_hash **orig_hash, | |
3748 | struct ftrace_hash *hash, | |
3749 | int enable) | |
3750 | { | |
3751 | struct ftrace_ops_hash old_hash_ops; | |
3752 | struct ftrace_hash *old_hash; | |
3753 | int ret; | |
3754 | ||
3755 | old_hash = *orig_hash; | |
3756 | old_hash_ops.filter_hash = ops->func_hash->filter_hash; | |
3757 | old_hash_ops.notrace_hash = ops->func_hash->notrace_hash; | |
3758 | ret = ftrace_hash_move(ops, enable, orig_hash, hash); | |
3759 | if (!ret) { | |
3760 | ftrace_ops_update_code(ops, &old_hash_ops); | |
3761 | free_ftrace_hash_rcu(old_hash); | |
3762 | } | |
3763 | return ret; | |
3764 | } | |
64e7c440 | 3765 | |
f6180773 SR |
3766 | /* |
3767 | * We register the module command as a template to show others how | |
3768 | * to register the a command as well. | |
3769 | */ | |
3770 | ||
3771 | static int | |
04ec7bb6 | 3772 | ftrace_mod_callback(struct trace_array *tr, struct ftrace_hash *hash, |
f0a3b154 | 3773 | char *func, char *cmd, char *module, int enable) |
f6180773 | 3774 | { |
5e3949f0 | 3775 | int ret; |
f6180773 SR |
3776 | |
3777 | /* | |
3778 | * cmd == 'mod' because we only registered this func | |
3779 | * for the 'mod' ftrace_func_command. | |
3780 | * But if you register one func with multiple commands, | |
3781 | * you can tell which command was used by the cmd | |
3782 | * parameter. | |
3783 | */ | |
f0a3b154 | 3784 | ret = match_records(hash, func, strlen(func), module); |
b448c4e3 | 3785 | if (!ret) |
5e3949f0 | 3786 | return -EINVAL; |
b448c4e3 SR |
3787 | if (ret < 0) |
3788 | return ret; | |
b448c4e3 | 3789 | return 0; |
f6180773 SR |
3790 | } |
3791 | ||
3792 | static struct ftrace_func_command ftrace_mod_cmd = { | |
3793 | .name = "mod", | |
3794 | .func = ftrace_mod_callback, | |
3795 | }; | |
3796 | ||
3797 | static int __init ftrace_mod_cmd_init(void) | |
3798 | { | |
3799 | return register_ftrace_command(&ftrace_mod_cmd); | |
3800 | } | |
6f415672 | 3801 | core_initcall(ftrace_mod_cmd_init); |
f6180773 | 3802 | |
2f5f6ad9 | 3803 | static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 3804 | struct ftrace_ops *op, struct pt_regs *pt_regs) |
59df055f | 3805 | { |
eee8ded1 | 3806 | struct ftrace_probe_ops *probe_ops; |
7b60f3d8 | 3807 | struct ftrace_func_probe *probe; |
59df055f | 3808 | |
7b60f3d8 SRV |
3809 | probe = container_of(op, struct ftrace_func_probe, ops); |
3810 | probe_ops = probe->probe_ops; | |
59df055f SR |
3811 | |
3812 | /* | |
3813 | * Disable preemption for these calls to prevent a RCU grace | |
3814 | * period. This syncs the hash iteration and freeing of items | |
3815 | * on the hash. rcu_read_lock is too dangerous here. | |
3816 | */ | |
5168ae50 | 3817 | preempt_disable_notrace(); |
6e444319 | 3818 | probe_ops->func(ip, parent_ip, probe->tr, probe_ops, probe->data); |
5168ae50 | 3819 | preempt_enable_notrace(); |
59df055f SR |
3820 | } |
3821 | ||
41794f19 SRV |
3822 | struct ftrace_func_map { |
3823 | struct ftrace_func_entry entry; | |
3824 | void *data; | |
59df055f SR |
3825 | }; |
3826 | ||
41794f19 SRV |
3827 | struct ftrace_func_mapper { |
3828 | struct ftrace_hash hash; | |
3829 | }; | |
59df055f | 3830 | |
41794f19 SRV |
3831 | /** |
3832 | * allocate_ftrace_func_mapper - allocate a new ftrace_func_mapper | |
3833 | * | |
3834 | * Returns a ftrace_func_mapper descriptor that can be used to map ips to data. | |
3835 | */ | |
3836 | struct ftrace_func_mapper *allocate_ftrace_func_mapper(void) | |
59df055f | 3837 | { |
41794f19 | 3838 | struct ftrace_hash *hash; |
59df055f | 3839 | |
41794f19 SRV |
3840 | /* |
3841 | * The mapper is simply a ftrace_hash, but since the entries | |
3842 | * in the hash are not ftrace_func_entry type, we define it | |
3843 | * as a separate structure. | |
3844 | */ | |
3845 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); | |
3846 | return (struct ftrace_func_mapper *)hash; | |
3847 | } | |
59df055f | 3848 | |
41794f19 SRV |
3849 | /** |
3850 | * ftrace_func_mapper_find_ip - Find some data mapped to an ip | |
3851 | * @mapper: The mapper that has the ip maps | |
3852 | * @ip: the instruction pointer to find the data for | |
3853 | * | |
3854 | * Returns the data mapped to @ip if found otherwise NULL. The return | |
3855 | * is actually the address of the mapper data pointer. The address is | |
3856 | * returned for use cases where the data is no bigger than a long, and | |
3857 | * the user can use the data pointer as its data instead of having to | |
3858 | * allocate more memory for the reference. | |
3859 | */ | |
3860 | void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper, | |
3861 | unsigned long ip) | |
3862 | { | |
3863 | struct ftrace_func_entry *entry; | |
3864 | struct ftrace_func_map *map; | |
59df055f | 3865 | |
41794f19 SRV |
3866 | entry = ftrace_lookup_ip(&mapper->hash, ip); |
3867 | if (!entry) | |
3868 | return NULL; | |
b848914c | 3869 | |
41794f19 SRV |
3870 | map = (struct ftrace_func_map *)entry; |
3871 | return &map->data; | |
59df055f SR |
3872 | } |
3873 | ||
41794f19 SRV |
3874 | /** |
3875 | * ftrace_func_mapper_add_ip - Map some data to an ip | |
3876 | * @mapper: The mapper that has the ip maps | |
3877 | * @ip: The instruction pointer address to map @data to | |
3878 | * @data: The data to map to @ip | |
3879 | * | |
3880 | * Returns 0 on succes otherwise an error. | |
3881 | */ | |
3882 | int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper, | |
3883 | unsigned long ip, void *data) | |
59df055f | 3884 | { |
41794f19 SRV |
3885 | struct ftrace_func_entry *entry; |
3886 | struct ftrace_func_map *map; | |
59df055f | 3887 | |
41794f19 SRV |
3888 | entry = ftrace_lookup_ip(&mapper->hash, ip); |
3889 | if (entry) | |
3890 | return -EBUSY; | |
59df055f | 3891 | |
41794f19 SRV |
3892 | map = kmalloc(sizeof(*map), GFP_KERNEL); |
3893 | if (!map) | |
3894 | return -ENOMEM; | |
59df055f | 3895 | |
41794f19 SRV |
3896 | map->entry.ip = ip; |
3897 | map->data = data; | |
b848914c | 3898 | |
41794f19 | 3899 | __add_hash_entry(&mapper->hash, &map->entry); |
59df055f | 3900 | |
41794f19 SRV |
3901 | return 0; |
3902 | } | |
59df055f | 3903 | |
41794f19 SRV |
3904 | /** |
3905 | * ftrace_func_mapper_remove_ip - Remove an ip from the mapping | |
3906 | * @mapper: The mapper that has the ip maps | |
3907 | * @ip: The instruction pointer address to remove the data from | |
3908 | * | |
3909 | * Returns the data if it is found, otherwise NULL. | |
3910 | * Note, if the data pointer is used as the data itself, (see | |
3911 | * ftrace_func_mapper_find_ip(), then the return value may be meaningless, | |
3912 | * if the data pointer was set to zero. | |
3913 | */ | |
3914 | void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper, | |
3915 | unsigned long ip) | |
59df055f | 3916 | { |
41794f19 SRV |
3917 | struct ftrace_func_entry *entry; |
3918 | struct ftrace_func_map *map; | |
3919 | void *data; | |
3920 | ||
3921 | entry = ftrace_lookup_ip(&mapper->hash, ip); | |
3922 | if (!entry) | |
3923 | return NULL; | |
3924 | ||
3925 | map = (struct ftrace_func_map *)entry; | |
3926 | data = map->data; | |
3927 | ||
3928 | remove_hash_entry(&mapper->hash, entry); | |
59df055f | 3929 | kfree(entry); |
41794f19 SRV |
3930 | |
3931 | return data; | |
3932 | } | |
3933 | ||
3934 | /** | |
3935 | * free_ftrace_func_mapper - free a mapping of ips and data | |
3936 | * @mapper: The mapper that has the ip maps | |
3937 | * @free_func: A function to be called on each data item. | |
3938 | * | |
3939 | * This is used to free the function mapper. The @free_func is optional | |
3940 | * and can be used if the data needs to be freed as well. | |
3941 | */ | |
3942 | void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper, | |
3943 | ftrace_mapper_func free_func) | |
3944 | { | |
3945 | struct ftrace_func_entry *entry; | |
3946 | struct ftrace_func_map *map; | |
3947 | struct hlist_head *hhd; | |
3948 | int size = 1 << mapper->hash.size_bits; | |
3949 | int i; | |
3950 | ||
3951 | if (free_func && mapper->hash.count) { | |
3952 | for (i = 0; i < size; i++) { | |
3953 | hhd = &mapper->hash.buckets[i]; | |
3954 | hlist_for_each_entry(entry, hhd, hlist) { | |
3955 | map = (struct ftrace_func_map *)entry; | |
3956 | free_func(map); | |
3957 | } | |
3958 | } | |
3959 | } | |
3960 | free_ftrace_hash(&mapper->hash); | |
3961 | } | |
3962 | ||
7b60f3d8 SRV |
3963 | static void release_probe(struct ftrace_func_probe *probe) |
3964 | { | |
3965 | struct ftrace_probe_ops *probe_ops; | |
3966 | ||
3967 | mutex_lock(&ftrace_lock); | |
3968 | ||
3969 | WARN_ON(probe->ref <= 0); | |
3970 | ||
3971 | /* Subtract the ref that was used to protect this instance */ | |
3972 | probe->ref--; | |
3973 | ||
3974 | if (!probe->ref) { | |
3975 | probe_ops = probe->probe_ops; | |
6e444319 SRV |
3976 | /* |
3977 | * Sending zero as ip tells probe_ops to free | |
3978 | * the probe->data itself | |
3979 | */ | |
3980 | if (probe_ops->free) | |
3981 | probe_ops->free(probe_ops, probe->tr, 0, probe->data); | |
7b60f3d8 SRV |
3982 | list_del(&probe->list); |
3983 | kfree(probe); | |
3984 | } | |
3985 | mutex_unlock(&ftrace_lock); | |
3986 | } | |
3987 | ||
3988 | static void acquire_probe_locked(struct ftrace_func_probe *probe) | |
3989 | { | |
3990 | /* | |
3991 | * Add one ref to keep it from being freed when releasing the | |
3992 | * ftrace_lock mutex. | |
3993 | */ | |
3994 | probe->ref++; | |
59df055f SR |
3995 | } |
3996 | ||
59df055f | 3997 | int |
04ec7bb6 | 3998 | register_ftrace_function_probe(char *glob, struct trace_array *tr, |
7b60f3d8 SRV |
3999 | struct ftrace_probe_ops *probe_ops, |
4000 | void *data) | |
59df055f | 4001 | { |
1ec3a81a | 4002 | struct ftrace_func_entry *entry; |
7b60f3d8 | 4003 | struct ftrace_func_probe *probe; |
1ec3a81a SRV |
4004 | struct ftrace_hash **orig_hash; |
4005 | struct ftrace_hash *old_hash; | |
e1df4cb6 | 4006 | struct ftrace_hash *hash; |
59df055f | 4007 | int count = 0; |
1ec3a81a | 4008 | int size; |
e1df4cb6 | 4009 | int ret; |
1ec3a81a | 4010 | int i; |
59df055f | 4011 | |
04ec7bb6 | 4012 | if (WARN_ON(!tr)) |
59df055f SR |
4013 | return -EINVAL; |
4014 | ||
1ec3a81a SRV |
4015 | /* We do not support '!' for function probes */ |
4016 | if (WARN_ON(glob[0] == '!')) | |
59df055f | 4017 | return -EINVAL; |
59df055f | 4018 | |
7485058e | 4019 | |
7b60f3d8 SRV |
4020 | mutex_lock(&ftrace_lock); |
4021 | /* Check if the probe_ops is already registered */ | |
4022 | list_for_each_entry(probe, &tr->func_probes, list) { | |
4023 | if (probe->probe_ops == probe_ops) | |
4024 | break; | |
e1df4cb6 | 4025 | } |
7b60f3d8 SRV |
4026 | if (&probe->list == &tr->func_probes) { |
4027 | probe = kzalloc(sizeof(*probe), GFP_KERNEL); | |
4028 | if (!probe) { | |
4029 | mutex_unlock(&ftrace_lock); | |
4030 | return -ENOMEM; | |
4031 | } | |
4032 | probe->probe_ops = probe_ops; | |
4033 | probe->ops.func = function_trace_probe_call; | |
4034 | probe->tr = tr; | |
4035 | ftrace_ops_init(&probe->ops); | |
4036 | list_add(&probe->list, &tr->func_probes); | |
e1df4cb6 | 4037 | } |
59df055f | 4038 | |
7b60f3d8 | 4039 | acquire_probe_locked(probe); |
5ae0bf59 | 4040 | |
7b60f3d8 | 4041 | mutex_unlock(&ftrace_lock); |
59df055f | 4042 | |
7b60f3d8 | 4043 | mutex_lock(&probe->ops.func_hash->regex_lock); |
546fece4 | 4044 | |
7b60f3d8 | 4045 | orig_hash = &probe->ops.func_hash->filter_hash; |
1ec3a81a SRV |
4046 | old_hash = *orig_hash; |
4047 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash); | |
59df055f | 4048 | |
1ec3a81a | 4049 | ret = ftrace_match_records(hash, glob, strlen(glob)); |
59df055f | 4050 | |
1ec3a81a SRV |
4051 | /* Nothing found? */ |
4052 | if (!ret) | |
4053 | ret = -EINVAL; | |
59df055f | 4054 | |
1ec3a81a SRV |
4055 | if (ret < 0) |
4056 | goto out; | |
59df055f | 4057 | |
1ec3a81a SRV |
4058 | size = 1 << hash->size_bits; |
4059 | for (i = 0; i < size; i++) { | |
4060 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { | |
4061 | if (ftrace_lookup_ip(old_hash, entry->ip)) | |
59df055f | 4062 | continue; |
1ec3a81a SRV |
4063 | /* |
4064 | * The caller might want to do something special | |
4065 | * for each function we find. We call the callback | |
4066 | * to give the caller an opportunity to do so. | |
4067 | */ | |
7b60f3d8 SRV |
4068 | if (probe_ops->init) { |
4069 | ret = probe_ops->init(probe_ops, tr, | |
6e444319 SRV |
4070 | entry->ip, data, |
4071 | &probe->data); | |
4072 | if (ret < 0) { | |
4073 | if (probe_ops->free && count) | |
4074 | probe_ops->free(probe_ops, tr, | |
4075 | 0, probe->data); | |
4076 | probe->data = NULL; | |
eee8ded1 | 4077 | goto out; |
6e444319 | 4078 | } |
59df055f | 4079 | } |
1ec3a81a | 4080 | count++; |
59df055f | 4081 | } |
1ec3a81a | 4082 | } |
59df055f | 4083 | |
1ec3a81a | 4084 | mutex_lock(&ftrace_lock); |
59df055f | 4085 | |
7b60f3d8 SRV |
4086 | if (!count) { |
4087 | /* Nothing was added? */ | |
4088 | ret = -EINVAL; | |
4089 | goto out_unlock; | |
4090 | } | |
e1df4cb6 | 4091 | |
7b60f3d8 SRV |
4092 | ret = ftrace_hash_move_and_update_ops(&probe->ops, orig_hash, |
4093 | hash, 1); | |
1ec3a81a | 4094 | if (ret < 0) |
8d70725e | 4095 | goto err_unlock; |
8252ecf3 | 4096 | |
7b60f3d8 SRV |
4097 | /* One ref for each new function traced */ |
4098 | probe->ref += count; | |
8252ecf3 | 4099 | |
7b60f3d8 SRV |
4100 | if (!(probe->ops.flags & FTRACE_OPS_FL_ENABLED)) |
4101 | ret = ftrace_startup(&probe->ops, 0); | |
e1df4cb6 | 4102 | |
59df055f | 4103 | out_unlock: |
5ae0bf59 | 4104 | mutex_unlock(&ftrace_lock); |
8252ecf3 | 4105 | |
3296fc4e | 4106 | if (!ret) |
1ec3a81a | 4107 | ret = count; |
5ae0bf59 | 4108 | out: |
7b60f3d8 | 4109 | mutex_unlock(&probe->ops.func_hash->regex_lock); |
e1df4cb6 | 4110 | free_ftrace_hash(hash); |
59df055f | 4111 | |
7b60f3d8 | 4112 | release_probe(probe); |
59df055f | 4113 | |
1ec3a81a | 4114 | return ret; |
59df055f | 4115 | |
8d70725e | 4116 | err_unlock: |
7b60f3d8 | 4117 | if (!probe_ops->free || !count) |
8d70725e SRV |
4118 | goto out_unlock; |
4119 | ||
4120 | /* Failed to do the move, need to call the free functions */ | |
4121 | for (i = 0; i < size; i++) { | |
4122 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { | |
4123 | if (ftrace_lookup_ip(old_hash, entry->ip)) | |
4124 | continue; | |
6e444319 | 4125 | probe_ops->free(probe_ops, tr, entry->ip, probe->data); |
8d70725e SRV |
4126 | } |
4127 | } | |
4128 | goto out_unlock; | |
59df055f SR |
4129 | } |
4130 | ||
d3d532d7 | 4131 | int |
7b60f3d8 SRV |
4132 | unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr, |
4133 | struct ftrace_probe_ops *probe_ops) | |
59df055f | 4134 | { |
82cc4fc2 | 4135 | struct ftrace_ops_hash old_hash_ops; |
eee8ded1 | 4136 | struct ftrace_func_entry *entry; |
7b60f3d8 | 4137 | struct ftrace_func_probe *probe; |
3ba00929 | 4138 | struct ftrace_glob func_g; |
1ec3a81a SRV |
4139 | struct ftrace_hash **orig_hash; |
4140 | struct ftrace_hash *old_hash; | |
1ec3a81a | 4141 | struct ftrace_hash *hash = NULL; |
b67bfe0d | 4142 | struct hlist_node *tmp; |
eee8ded1 | 4143 | struct hlist_head hhd; |
59df055f | 4144 | char str[KSYM_SYMBOL_LEN]; |
7b60f3d8 SRV |
4145 | int count = 0; |
4146 | int i, ret = -ENODEV; | |
eee8ded1 | 4147 | int size; |
59df055f | 4148 | |
b36461da | 4149 | if (glob && (strcmp(glob, "*") == 0 || !strlen(glob))) |
3ba00929 | 4150 | func_g.search = NULL; |
b36461da | 4151 | else if (glob) { |
59df055f SR |
4152 | int not; |
4153 | ||
3ba00929 DS |
4154 | func_g.type = filter_parse_regex(glob, strlen(glob), |
4155 | &func_g.search, ¬); | |
4156 | func_g.len = strlen(func_g.search); | |
4157 | func_g.search = glob; | |
59df055f | 4158 | |
b6887d79 | 4159 | /* we do not support '!' for function probes */ |
59df055f | 4160 | if (WARN_ON(not)) |
d3d532d7 | 4161 | return -EINVAL; |
59df055f SR |
4162 | } |
4163 | ||
7b60f3d8 SRV |
4164 | mutex_lock(&ftrace_lock); |
4165 | /* Check if the probe_ops is already registered */ | |
4166 | list_for_each_entry(probe, &tr->func_probes, list) { | |
4167 | if (probe->probe_ops == probe_ops) | |
4168 | break; | |
59df055f | 4169 | } |
7b60f3d8 SRV |
4170 | if (&probe->list == &tr->func_probes) |
4171 | goto err_unlock_ftrace; | |
4172 | ||
4173 | ret = -EINVAL; | |
4174 | if (!(probe->ops.flags & FTRACE_OPS_FL_INITIALIZED)) | |
4175 | goto err_unlock_ftrace; | |
4176 | ||
4177 | acquire_probe_locked(probe); | |
4178 | ||
4179 | mutex_unlock(&ftrace_lock); | |
59df055f | 4180 | |
7b60f3d8 | 4181 | mutex_lock(&probe->ops.func_hash->regex_lock); |
1ec3a81a | 4182 | |
7b60f3d8 | 4183 | orig_hash = &probe->ops.func_hash->filter_hash; |
1ec3a81a SRV |
4184 | old_hash = *orig_hash; |
4185 | ||
1ec3a81a SRV |
4186 | if (ftrace_hash_empty(old_hash)) |
4187 | goto out_unlock; | |
e1df4cb6 | 4188 | |
82cc4fc2 SRV |
4189 | old_hash_ops.filter_hash = old_hash; |
4190 | /* Probes only have filters */ | |
4191 | old_hash_ops.notrace_hash = NULL; | |
4192 | ||
d3d532d7 | 4193 | ret = -ENOMEM; |
1ec3a81a | 4194 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash); |
e1df4cb6 | 4195 | if (!hash) |
e1df4cb6 SRRH |
4196 | goto out_unlock; |
4197 | ||
eee8ded1 | 4198 | INIT_HLIST_HEAD(&hhd); |
59df055f | 4199 | |
eee8ded1 SRV |
4200 | size = 1 << hash->size_bits; |
4201 | for (i = 0; i < size; i++) { | |
4202 | hlist_for_each_entry_safe(entry, tmp, &hash->buckets[i], hlist) { | |
59df055f | 4203 | |
3ba00929 | 4204 | if (func_g.search) { |
59df055f SR |
4205 | kallsyms_lookup(entry->ip, NULL, NULL, |
4206 | NULL, str); | |
3ba00929 | 4207 | if (!ftrace_match(str, &func_g)) |
59df055f SR |
4208 | continue; |
4209 | } | |
7b60f3d8 | 4210 | count++; |
eee8ded1 SRV |
4211 | remove_hash_entry(hash, entry); |
4212 | hlist_add_head(&entry->hlist, &hhd); | |
59df055f SR |
4213 | } |
4214 | } | |
d3d532d7 SRV |
4215 | |
4216 | /* Nothing found? */ | |
7b60f3d8 | 4217 | if (!count) { |
d3d532d7 SRV |
4218 | ret = -EINVAL; |
4219 | goto out_unlock; | |
4220 | } | |
4221 | ||
3f2367ba | 4222 | mutex_lock(&ftrace_lock); |
1ec3a81a | 4223 | |
7b60f3d8 | 4224 | WARN_ON(probe->ref < count); |
eee8ded1 | 4225 | |
7b60f3d8 | 4226 | probe->ref -= count; |
1ec3a81a | 4227 | |
7b60f3d8 SRV |
4228 | if (ftrace_hash_empty(hash)) |
4229 | ftrace_shutdown(&probe->ops, 0); | |
4230 | ||
4231 | ret = ftrace_hash_move_and_update_ops(&probe->ops, orig_hash, | |
1ec3a81a | 4232 | hash, 1); |
82cc4fc2 SRV |
4233 | |
4234 | /* still need to update the function call sites */ | |
1ec3a81a | 4235 | if (ftrace_enabled && !ftrace_hash_empty(hash)) |
7b60f3d8 | 4236 | ftrace_run_modify_code(&probe->ops, FTRACE_UPDATE_CALLS, |
82cc4fc2 | 4237 | &old_hash_ops); |
7818b388 | 4238 | synchronize_sched(); |
3296fc4e | 4239 | |
eee8ded1 SRV |
4240 | hlist_for_each_entry_safe(entry, tmp, &hhd, hlist) { |
4241 | hlist_del(&entry->hlist); | |
7b60f3d8 | 4242 | if (probe_ops->free) |
6e444319 | 4243 | probe_ops->free(probe_ops, tr, entry->ip, probe->data); |
eee8ded1 | 4244 | kfree(entry); |
7818b388 | 4245 | } |
3f2367ba | 4246 | mutex_unlock(&ftrace_lock); |
3ba00929 | 4247 | |
e1df4cb6 | 4248 | out_unlock: |
7b60f3d8 | 4249 | mutex_unlock(&probe->ops.func_hash->regex_lock); |
e1df4cb6 | 4250 | free_ftrace_hash(hash); |
59df055f | 4251 | |
7b60f3d8 | 4252 | release_probe(probe); |
59df055f | 4253 | |
7b60f3d8 | 4254 | return ret; |
59df055f | 4255 | |
7b60f3d8 SRV |
4256 | err_unlock_ftrace: |
4257 | mutex_unlock(&ftrace_lock); | |
d3d532d7 | 4258 | return ret; |
59df055f SR |
4259 | } |
4260 | ||
f6180773 SR |
4261 | static LIST_HEAD(ftrace_commands); |
4262 | static DEFINE_MUTEX(ftrace_cmd_mutex); | |
4263 | ||
38de93ab TZ |
4264 | /* |
4265 | * Currently we only register ftrace commands from __init, so mark this | |
4266 | * __init too. | |
4267 | */ | |
4268 | __init int register_ftrace_command(struct ftrace_func_command *cmd) | |
f6180773 SR |
4269 | { |
4270 | struct ftrace_func_command *p; | |
4271 | int ret = 0; | |
4272 | ||
4273 | mutex_lock(&ftrace_cmd_mutex); | |
4274 | list_for_each_entry(p, &ftrace_commands, list) { | |
4275 | if (strcmp(cmd->name, p->name) == 0) { | |
4276 | ret = -EBUSY; | |
4277 | goto out_unlock; | |
4278 | } | |
4279 | } | |
4280 | list_add(&cmd->list, &ftrace_commands); | |
4281 | out_unlock: | |
4282 | mutex_unlock(&ftrace_cmd_mutex); | |
4283 | ||
4284 | return ret; | |
4285 | } | |
4286 | ||
38de93ab TZ |
4287 | /* |
4288 | * Currently we only unregister ftrace commands from __init, so mark | |
4289 | * this __init too. | |
4290 | */ | |
4291 | __init int unregister_ftrace_command(struct ftrace_func_command *cmd) | |
f6180773 SR |
4292 | { |
4293 | struct ftrace_func_command *p, *n; | |
4294 | int ret = -ENODEV; | |
4295 | ||
4296 | mutex_lock(&ftrace_cmd_mutex); | |
4297 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { | |
4298 | if (strcmp(cmd->name, p->name) == 0) { | |
4299 | ret = 0; | |
4300 | list_del_init(&p->list); | |
4301 | goto out_unlock; | |
4302 | } | |
4303 | } | |
4304 | out_unlock: | |
4305 | mutex_unlock(&ftrace_cmd_mutex); | |
4306 | ||
4307 | return ret; | |
4308 | } | |
4309 | ||
04ec7bb6 | 4310 | static int ftrace_process_regex(struct ftrace_iterator *iter, |
33dc9b12 | 4311 | char *buff, int len, int enable) |
64e7c440 | 4312 | { |
04ec7bb6 | 4313 | struct ftrace_hash *hash = iter->hash; |
d2afd57a | 4314 | struct trace_array *tr = iter->ops->private; |
f6180773 | 4315 | char *func, *command, *next = buff; |
6a24a244 | 4316 | struct ftrace_func_command *p; |
0aff1c0c | 4317 | int ret = -EINVAL; |
64e7c440 SR |
4318 | |
4319 | func = strsep(&next, ":"); | |
4320 | ||
4321 | if (!next) { | |
1cf41dd7 | 4322 | ret = ftrace_match_records(hash, func, len); |
b448c4e3 SR |
4323 | if (!ret) |
4324 | ret = -EINVAL; | |
4325 | if (ret < 0) | |
4326 | return ret; | |
4327 | return 0; | |
64e7c440 SR |
4328 | } |
4329 | ||
f6180773 | 4330 | /* command found */ |
64e7c440 SR |
4331 | |
4332 | command = strsep(&next, ":"); | |
4333 | ||
04ec7bb6 SRV |
4334 | if (WARN_ON_ONCE(!tr)) |
4335 | return -EINVAL; | |
4336 | ||
f6180773 SR |
4337 | mutex_lock(&ftrace_cmd_mutex); |
4338 | list_for_each_entry(p, &ftrace_commands, list) { | |
4339 | if (strcmp(p->name, command) == 0) { | |
04ec7bb6 | 4340 | ret = p->func(tr, hash, func, command, next, enable); |
f6180773 SR |
4341 | goto out_unlock; |
4342 | } | |
64e7c440 | 4343 | } |
f6180773 SR |
4344 | out_unlock: |
4345 | mutex_unlock(&ftrace_cmd_mutex); | |
64e7c440 | 4346 | |
f6180773 | 4347 | return ret; |
64e7c440 SR |
4348 | } |
4349 | ||
e309b41d | 4350 | static ssize_t |
41c52c0d SR |
4351 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
4352 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
4353 | { |
4354 | struct ftrace_iterator *iter; | |
689fd8b6 | 4355 | struct trace_parser *parser; |
4356 | ssize_t ret, read; | |
5072c59f | 4357 | |
4ba7978e | 4358 | if (!cnt) |
5072c59f SR |
4359 | return 0; |
4360 | ||
5072c59f SR |
4361 | if (file->f_mode & FMODE_READ) { |
4362 | struct seq_file *m = file->private_data; | |
4363 | iter = m->private; | |
4364 | } else | |
4365 | iter = file->private_data; | |
4366 | ||
f04f24fb | 4367 | if (unlikely(ftrace_disabled)) |
3f2367ba MH |
4368 | return -ENODEV; |
4369 | ||
4370 | /* iter->hash is a local copy, so we don't need regex_lock */ | |
f04f24fb | 4371 | |
689fd8b6 | 4372 | parser = &iter->parser; |
4373 | read = trace_get_user(parser, ubuf, cnt, ppos); | |
5072c59f | 4374 | |
4ba7978e | 4375 | if (read >= 0 && trace_parser_loaded(parser) && |
689fd8b6 | 4376 | !trace_parser_cont(parser)) { |
04ec7bb6 | 4377 | ret = ftrace_process_regex(iter, parser->buffer, |
689fd8b6 | 4378 | parser->idx, enable); |
313254a9 | 4379 | trace_parser_clear(parser); |
7c088b51 | 4380 | if (ret < 0) |
3f2367ba | 4381 | goto out; |
eda1e328 | 4382 | } |
5072c59f | 4383 | |
5072c59f | 4384 | ret = read; |
3f2367ba | 4385 | out: |
5072c59f SR |
4386 | return ret; |
4387 | } | |
4388 | ||
fc13cb0c | 4389 | ssize_t |
41c52c0d SR |
4390 | ftrace_filter_write(struct file *file, const char __user *ubuf, |
4391 | size_t cnt, loff_t *ppos) | |
4392 | { | |
4393 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
4394 | } | |
4395 | ||
fc13cb0c | 4396 | ssize_t |
41c52c0d SR |
4397 | ftrace_notrace_write(struct file *file, const char __user *ubuf, |
4398 | size_t cnt, loff_t *ppos) | |
4399 | { | |
4400 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
4401 | } | |
4402 | ||
33dc9b12 | 4403 | static int |
647664ea MH |
4404 | ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) |
4405 | { | |
4406 | struct ftrace_func_entry *entry; | |
4407 | ||
4408 | if (!ftrace_location(ip)) | |
4409 | return -EINVAL; | |
4410 | ||
4411 | if (remove) { | |
4412 | entry = ftrace_lookup_ip(hash, ip); | |
4413 | if (!entry) | |
4414 | return -ENOENT; | |
4415 | free_hash_entry(hash, entry); | |
4416 | return 0; | |
4417 | } | |
4418 | ||
4419 | return add_hash_entry(hash, ip); | |
4420 | } | |
4421 | ||
4422 | static int | |
4423 | ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, | |
4424 | unsigned long ip, int remove, int reset, int enable) | |
41c52c0d | 4425 | { |
33dc9b12 | 4426 | struct ftrace_hash **orig_hash; |
f45948e8 | 4427 | struct ftrace_hash *hash; |
33dc9b12 | 4428 | int ret; |
f45948e8 | 4429 | |
41c52c0d | 4430 | if (unlikely(ftrace_disabled)) |
33dc9b12 | 4431 | return -ENODEV; |
41c52c0d | 4432 | |
33b7f99c | 4433 | mutex_lock(&ops->func_hash->regex_lock); |
3f2367ba | 4434 | |
f45948e8 | 4435 | if (enable) |
33b7f99c | 4436 | orig_hash = &ops->func_hash->filter_hash; |
f45948e8 | 4437 | else |
33b7f99c | 4438 | orig_hash = &ops->func_hash->notrace_hash; |
33dc9b12 | 4439 | |
b972cc58 WN |
4440 | if (reset) |
4441 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); | |
4442 | else | |
4443 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
4444 | ||
3f2367ba MH |
4445 | if (!hash) { |
4446 | ret = -ENOMEM; | |
4447 | goto out_regex_unlock; | |
4448 | } | |
f45948e8 | 4449 | |
ac483c44 JO |
4450 | if (buf && !ftrace_match_records(hash, buf, len)) { |
4451 | ret = -EINVAL; | |
4452 | goto out_regex_unlock; | |
4453 | } | |
647664ea MH |
4454 | if (ip) { |
4455 | ret = ftrace_match_addr(hash, ip, remove); | |
4456 | if (ret < 0) | |
4457 | goto out_regex_unlock; | |
4458 | } | |
33dc9b12 SR |
4459 | |
4460 | mutex_lock(&ftrace_lock); | |
e16b35dd | 4461 | ret = ftrace_hash_move_and_update_ops(ops, orig_hash, hash, enable); |
33dc9b12 SR |
4462 | mutex_unlock(&ftrace_lock); |
4463 | ||
ac483c44 | 4464 | out_regex_unlock: |
33b7f99c | 4465 | mutex_unlock(&ops->func_hash->regex_lock); |
33dc9b12 SR |
4466 | |
4467 | free_ftrace_hash(hash); | |
4468 | return ret; | |
41c52c0d SR |
4469 | } |
4470 | ||
647664ea MH |
4471 | static int |
4472 | ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove, | |
4473 | int reset, int enable) | |
4474 | { | |
4475 | return ftrace_set_hash(ops, 0, 0, ip, remove, reset, enable); | |
4476 | } | |
4477 | ||
4478 | /** | |
4479 | * ftrace_set_filter_ip - set a function to filter on in ftrace by address | |
4480 | * @ops - the ops to set the filter with | |
4481 | * @ip - the address to add to or remove from the filter. | |
4482 | * @remove - non zero to remove the ip from the filter | |
4483 | * @reset - non zero to reset all filters before applying this filter. | |
4484 | * | |
4485 | * Filters denote which functions should be enabled when tracing is enabled | |
4486 | * If @ip is NULL, it failes to update filter. | |
4487 | */ | |
4488 | int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, | |
4489 | int remove, int reset) | |
4490 | { | |
f04f24fb | 4491 | ftrace_ops_init(ops); |
647664ea MH |
4492 | return ftrace_set_addr(ops, ip, remove, reset, 1); |
4493 | } | |
4494 | EXPORT_SYMBOL_GPL(ftrace_set_filter_ip); | |
4495 | ||
d032ae89 JF |
4496 | /** |
4497 | * ftrace_ops_set_global_filter - setup ops to use global filters | |
4498 | * @ops - the ops which will use the global filters | |
4499 | * | |
4500 | * ftrace users who need global function trace filtering should call this. | |
4501 | * It can set the global filter only if ops were not initialized before. | |
4502 | */ | |
4503 | void ftrace_ops_set_global_filter(struct ftrace_ops *ops) | |
4504 | { | |
4505 | if (ops->flags & FTRACE_OPS_FL_INITIALIZED) | |
4506 | return; | |
4507 | ||
4508 | ftrace_ops_init(ops); | |
4509 | ops->func_hash = &global_ops.local_hash; | |
4510 | } | |
4511 | EXPORT_SYMBOL_GPL(ftrace_ops_set_global_filter); | |
4512 | ||
647664ea MH |
4513 | static int |
4514 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, | |
4515 | int reset, int enable) | |
4516 | { | |
4517 | return ftrace_set_hash(ops, buf, len, 0, 0, reset, enable); | |
4518 | } | |
4519 | ||
77a2b37d SR |
4520 | /** |
4521 | * ftrace_set_filter - set a function to filter on in ftrace | |
936e074b SR |
4522 | * @ops - the ops to set the filter with |
4523 | * @buf - the string that holds the function filter text. | |
4524 | * @len - the length of the string. | |
4525 | * @reset - non zero to reset all filters before applying this filter. | |
4526 | * | |
4527 | * Filters denote which functions should be enabled when tracing is enabled. | |
4528 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
4529 | */ | |
ac483c44 | 4530 | int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
4531 | int len, int reset) |
4532 | { | |
f04f24fb | 4533 | ftrace_ops_init(ops); |
ac483c44 | 4534 | return ftrace_set_regex(ops, buf, len, reset, 1); |
936e074b SR |
4535 | } |
4536 | EXPORT_SYMBOL_GPL(ftrace_set_filter); | |
4537 | ||
4538 | /** | |
4539 | * ftrace_set_notrace - set a function to not trace in ftrace | |
4540 | * @ops - the ops to set the notrace filter with | |
4541 | * @buf - the string that holds the function notrace text. | |
4542 | * @len - the length of the string. | |
4543 | * @reset - non zero to reset all filters before applying this filter. | |
4544 | * | |
4545 | * Notrace Filters denote which functions should not be enabled when tracing | |
4546 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
4547 | * for tracing. | |
4548 | */ | |
ac483c44 | 4549 | int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
4550 | int len, int reset) |
4551 | { | |
f04f24fb | 4552 | ftrace_ops_init(ops); |
ac483c44 | 4553 | return ftrace_set_regex(ops, buf, len, reset, 0); |
936e074b SR |
4554 | } |
4555 | EXPORT_SYMBOL_GPL(ftrace_set_notrace); | |
4556 | /** | |
8d1b065d | 4557 | * ftrace_set_global_filter - set a function to filter on with global tracers |
77a2b37d SR |
4558 | * @buf - the string that holds the function filter text. |
4559 | * @len - the length of the string. | |
4560 | * @reset - non zero to reset all filters before applying this filter. | |
4561 | * | |
4562 | * Filters denote which functions should be enabled when tracing is enabled. | |
4563 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
4564 | */ | |
936e074b | 4565 | void ftrace_set_global_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 4566 | { |
f45948e8 | 4567 | ftrace_set_regex(&global_ops, buf, len, reset, 1); |
41c52c0d | 4568 | } |
936e074b | 4569 | EXPORT_SYMBOL_GPL(ftrace_set_global_filter); |
4eebcc81 | 4570 | |
41c52c0d | 4571 | /** |
8d1b065d | 4572 | * ftrace_set_global_notrace - set a function to not trace with global tracers |
41c52c0d SR |
4573 | * @buf - the string that holds the function notrace text. |
4574 | * @len - the length of the string. | |
4575 | * @reset - non zero to reset all filters before applying this filter. | |
4576 | * | |
4577 | * Notrace Filters denote which functions should not be enabled when tracing | |
4578 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
4579 | * for tracing. | |
4580 | */ | |
936e074b | 4581 | void ftrace_set_global_notrace(unsigned char *buf, int len, int reset) |
41c52c0d | 4582 | { |
f45948e8 | 4583 | ftrace_set_regex(&global_ops, buf, len, reset, 0); |
77a2b37d | 4584 | } |
936e074b | 4585 | EXPORT_SYMBOL_GPL(ftrace_set_global_notrace); |
77a2b37d | 4586 | |
2af15d6a SR |
4587 | /* |
4588 | * command line interface to allow users to set filters on boot up. | |
4589 | */ | |
4590 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE | |
4591 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; | |
4592 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; | |
4593 | ||
f1ed7c74 SRRH |
4594 | /* Used by function selftest to not test if filter is set */ |
4595 | bool ftrace_filter_param __initdata; | |
4596 | ||
2af15d6a SR |
4597 | static int __init set_ftrace_notrace(char *str) |
4598 | { | |
f1ed7c74 | 4599 | ftrace_filter_param = true; |
75761cc1 | 4600 | strlcpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
4601 | return 1; |
4602 | } | |
4603 | __setup("ftrace_notrace=", set_ftrace_notrace); | |
4604 | ||
4605 | static int __init set_ftrace_filter(char *str) | |
4606 | { | |
f1ed7c74 | 4607 | ftrace_filter_param = true; |
75761cc1 | 4608 | strlcpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
4609 | return 1; |
4610 | } | |
4611 | __setup("ftrace_filter=", set_ftrace_filter); | |
4612 | ||
369bc18f | 4613 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
f6060f46 | 4614 | static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; |
0d7d9a16 | 4615 | static char ftrace_graph_notrace_buf[FTRACE_FILTER_SIZE] __initdata; |
b9b0c831 | 4616 | static int ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer); |
801c29fd | 4617 | |
f3bea491 SRRH |
4618 | static unsigned long save_global_trampoline; |
4619 | static unsigned long save_global_flags; | |
4620 | ||
369bc18f SA |
4621 | static int __init set_graph_function(char *str) |
4622 | { | |
06f43d66 | 4623 | strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); |
369bc18f SA |
4624 | return 1; |
4625 | } | |
4626 | __setup("ftrace_graph_filter=", set_graph_function); | |
4627 | ||
0d7d9a16 NK |
4628 | static int __init set_graph_notrace_function(char *str) |
4629 | { | |
4630 | strlcpy(ftrace_graph_notrace_buf, str, FTRACE_FILTER_SIZE); | |
4631 | return 1; | |
4632 | } | |
4633 | __setup("ftrace_graph_notrace=", set_graph_notrace_function); | |
4634 | ||
65a50c65 TB |
4635 | static int __init set_graph_max_depth_function(char *str) |
4636 | { | |
4637 | if (!str) | |
4638 | return 0; | |
4639 | fgraph_max_depth = simple_strtoul(str, NULL, 0); | |
4640 | return 1; | |
4641 | } | |
4642 | __setup("ftrace_graph_max_depth=", set_graph_max_depth_function); | |
0d7d9a16 NK |
4643 | |
4644 | static void __init set_ftrace_early_graph(char *buf, int enable) | |
369bc18f SA |
4645 | { |
4646 | int ret; | |
4647 | char *func; | |
b9b0c831 | 4648 | struct ftrace_hash *hash; |
0d7d9a16 | 4649 | |
92ad18ec SRV |
4650 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); |
4651 | if (WARN_ON(!hash)) | |
4652 | return; | |
369bc18f SA |
4653 | |
4654 | while (buf) { | |
4655 | func = strsep(&buf, ","); | |
4656 | /* we allow only one expression at a time */ | |
b9b0c831 | 4657 | ret = ftrace_graph_set_hash(hash, func); |
369bc18f SA |
4658 | if (ret) |
4659 | printk(KERN_DEBUG "ftrace: function %s not " | |
4660 | "traceable\n", func); | |
4661 | } | |
92ad18ec SRV |
4662 | |
4663 | if (enable) | |
4664 | ftrace_graph_hash = hash; | |
4665 | else | |
4666 | ftrace_graph_notrace_hash = hash; | |
369bc18f SA |
4667 | } |
4668 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
4669 | ||
2a85a37f SR |
4670 | void __init |
4671 | ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable) | |
2af15d6a SR |
4672 | { |
4673 | char *func; | |
4674 | ||
f04f24fb MH |
4675 | ftrace_ops_init(ops); |
4676 | ||
2af15d6a SR |
4677 | while (buf) { |
4678 | func = strsep(&buf, ","); | |
f45948e8 | 4679 | ftrace_set_regex(ops, func, strlen(func), 0, enable); |
2af15d6a SR |
4680 | } |
4681 | } | |
4682 | ||
4683 | static void __init set_ftrace_early_filters(void) | |
4684 | { | |
4685 | if (ftrace_filter_buf[0]) | |
2a85a37f | 4686 | ftrace_set_early_filter(&global_ops, ftrace_filter_buf, 1); |
2af15d6a | 4687 | if (ftrace_notrace_buf[0]) |
2a85a37f | 4688 | ftrace_set_early_filter(&global_ops, ftrace_notrace_buf, 0); |
369bc18f SA |
4689 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
4690 | if (ftrace_graph_buf[0]) | |
0d7d9a16 NK |
4691 | set_ftrace_early_graph(ftrace_graph_buf, 1); |
4692 | if (ftrace_graph_notrace_buf[0]) | |
4693 | set_ftrace_early_graph(ftrace_graph_notrace_buf, 0); | |
369bc18f | 4694 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
2af15d6a SR |
4695 | } |
4696 | ||
fc13cb0c | 4697 | int ftrace_regex_release(struct inode *inode, struct file *file) |
5072c59f SR |
4698 | { |
4699 | struct seq_file *m = (struct seq_file *)file->private_data; | |
4700 | struct ftrace_iterator *iter; | |
33dc9b12 | 4701 | struct ftrace_hash **orig_hash; |
689fd8b6 | 4702 | struct trace_parser *parser; |
ed926f9b | 4703 | int filter_hash; |
33dc9b12 | 4704 | int ret; |
5072c59f | 4705 | |
5072c59f SR |
4706 | if (file->f_mode & FMODE_READ) { |
4707 | iter = m->private; | |
5072c59f SR |
4708 | seq_release(inode, file); |
4709 | } else | |
4710 | iter = file->private_data; | |
4711 | ||
689fd8b6 | 4712 | parser = &iter->parser; |
4713 | if (trace_parser_loaded(parser)) { | |
4714 | parser->buffer[parser->idx] = 0; | |
1cf41dd7 | 4715 | ftrace_match_records(iter->hash, parser->buffer, parser->idx); |
5072c59f SR |
4716 | } |
4717 | ||
689fd8b6 | 4718 | trace_parser_put(parser); |
689fd8b6 | 4719 | |
33b7f99c | 4720 | mutex_lock(&iter->ops->func_hash->regex_lock); |
3f2367ba | 4721 | |
058e297d | 4722 | if (file->f_mode & FMODE_WRITE) { |
ed926f9b SR |
4723 | filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); |
4724 | ||
4725 | if (filter_hash) | |
33b7f99c | 4726 | orig_hash = &iter->ops->func_hash->filter_hash; |
ed926f9b | 4727 | else |
33b7f99c | 4728 | orig_hash = &iter->ops->func_hash->notrace_hash; |
33dc9b12 | 4729 | |
058e297d | 4730 | mutex_lock(&ftrace_lock); |
e16b35dd SRV |
4731 | ret = ftrace_hash_move_and_update_ops(iter->ops, orig_hash, |
4732 | iter->hash, filter_hash); | |
058e297d | 4733 | mutex_unlock(&ftrace_lock); |
c20489da SRV |
4734 | } else { |
4735 | /* For read only, the hash is the ops hash */ | |
4736 | iter->hash = NULL; | |
058e297d | 4737 | } |
3f2367ba | 4738 | |
33b7f99c | 4739 | mutex_unlock(&iter->ops->func_hash->regex_lock); |
33dc9b12 SR |
4740 | free_ftrace_hash(iter->hash); |
4741 | kfree(iter); | |
058e297d | 4742 | |
5072c59f SR |
4743 | return 0; |
4744 | } | |
4745 | ||
5e2336a0 | 4746 | static const struct file_operations ftrace_avail_fops = { |
5072c59f SR |
4747 | .open = ftrace_avail_open, |
4748 | .read = seq_read, | |
4749 | .llseek = seq_lseek, | |
3be04b47 | 4750 | .release = seq_release_private, |
5072c59f SR |
4751 | }; |
4752 | ||
647bcd03 SR |
4753 | static const struct file_operations ftrace_enabled_fops = { |
4754 | .open = ftrace_enabled_open, | |
4755 | .read = seq_read, | |
4756 | .llseek = seq_lseek, | |
4757 | .release = seq_release_private, | |
4758 | }; | |
4759 | ||
5e2336a0 | 4760 | static const struct file_operations ftrace_filter_fops = { |
5072c59f | 4761 | .open = ftrace_filter_open, |
850a80cf | 4762 | .read = seq_read, |
5072c59f | 4763 | .write = ftrace_filter_write, |
098c879e | 4764 | .llseek = tracing_lseek, |
1cf41dd7 | 4765 | .release = ftrace_regex_release, |
5072c59f SR |
4766 | }; |
4767 | ||
5e2336a0 | 4768 | static const struct file_operations ftrace_notrace_fops = { |
41c52c0d | 4769 | .open = ftrace_notrace_open, |
850a80cf | 4770 | .read = seq_read, |
41c52c0d | 4771 | .write = ftrace_notrace_write, |
098c879e | 4772 | .llseek = tracing_lseek, |
1cf41dd7 | 4773 | .release = ftrace_regex_release, |
41c52c0d SR |
4774 | }; |
4775 | ||
ea4e2bc4 SR |
4776 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
4777 | ||
4778 | static DEFINE_MUTEX(graph_lock); | |
4779 | ||
b9b0c831 NK |
4780 | struct ftrace_hash *ftrace_graph_hash = EMPTY_HASH; |
4781 | struct ftrace_hash *ftrace_graph_notrace_hash = EMPTY_HASH; | |
4782 | ||
4783 | enum graph_filter_type { | |
4784 | GRAPH_FILTER_NOTRACE = 0, | |
4785 | GRAPH_FILTER_FUNCTION, | |
4786 | }; | |
ea4e2bc4 | 4787 | |
555fc781 SRV |
4788 | #define FTRACE_GRAPH_EMPTY ((void *)1) |
4789 | ||
faf982a6 | 4790 | struct ftrace_graph_data { |
e704eff3 SRV |
4791 | struct ftrace_hash *hash; |
4792 | struct ftrace_func_entry *entry; | |
4793 | int idx; /* for hash table iteration */ | |
4794 | enum graph_filter_type type; | |
4795 | struct ftrace_hash *new_hash; | |
4796 | const struct seq_operations *seq_ops; | |
4797 | struct trace_parser parser; | |
faf982a6 NK |
4798 | }; |
4799 | ||
ea4e2bc4 | 4800 | static void * |
85951842 | 4801 | __g_next(struct seq_file *m, loff_t *pos) |
ea4e2bc4 | 4802 | { |
faf982a6 | 4803 | struct ftrace_graph_data *fgd = m->private; |
b9b0c831 NK |
4804 | struct ftrace_func_entry *entry = fgd->entry; |
4805 | struct hlist_head *head; | |
4806 | int i, idx = fgd->idx; | |
faf982a6 | 4807 | |
b9b0c831 | 4808 | if (*pos >= fgd->hash->count) |
ea4e2bc4 | 4809 | return NULL; |
b9b0c831 NK |
4810 | |
4811 | if (entry) { | |
4812 | hlist_for_each_entry_continue(entry, hlist) { | |
4813 | fgd->entry = entry; | |
4814 | return entry; | |
4815 | } | |
4816 | ||
4817 | idx++; | |
4818 | } | |
4819 | ||
4820 | for (i = idx; i < 1 << fgd->hash->size_bits; i++) { | |
4821 | head = &fgd->hash->buckets[i]; | |
4822 | hlist_for_each_entry(entry, head, hlist) { | |
4823 | fgd->entry = entry; | |
4824 | fgd->idx = i; | |
4825 | return entry; | |
4826 | } | |
4827 | } | |
4828 | return NULL; | |
85951842 | 4829 | } |
ea4e2bc4 | 4830 | |
85951842 LZ |
4831 | static void * |
4832 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
4833 | { | |
4834 | (*pos)++; | |
4835 | return __g_next(m, pos); | |
ea4e2bc4 SR |
4836 | } |
4837 | ||
4838 | static void *g_start(struct seq_file *m, loff_t *pos) | |
4839 | { | |
faf982a6 NK |
4840 | struct ftrace_graph_data *fgd = m->private; |
4841 | ||
ea4e2bc4 SR |
4842 | mutex_lock(&graph_lock); |
4843 | ||
649b988b SRV |
4844 | if (fgd->type == GRAPH_FILTER_FUNCTION) |
4845 | fgd->hash = rcu_dereference_protected(ftrace_graph_hash, | |
4846 | lockdep_is_held(&graph_lock)); | |
4847 | else | |
4848 | fgd->hash = rcu_dereference_protected(ftrace_graph_notrace_hash, | |
4849 | lockdep_is_held(&graph_lock)); | |
4850 | ||
f9349a8f | 4851 | /* Nothing, tell g_show to print all functions are enabled */ |
b9b0c831 | 4852 | if (ftrace_hash_empty(fgd->hash) && !*pos) |
555fc781 | 4853 | return FTRACE_GRAPH_EMPTY; |
f9349a8f | 4854 | |
b9b0c831 NK |
4855 | fgd->idx = 0; |
4856 | fgd->entry = NULL; | |
85951842 | 4857 | return __g_next(m, pos); |
ea4e2bc4 SR |
4858 | } |
4859 | ||
4860 | static void g_stop(struct seq_file *m, void *p) | |
4861 | { | |
4862 | mutex_unlock(&graph_lock); | |
4863 | } | |
4864 | ||
4865 | static int g_show(struct seq_file *m, void *v) | |
4866 | { | |
b9b0c831 | 4867 | struct ftrace_func_entry *entry = v; |
ea4e2bc4 | 4868 | |
b9b0c831 | 4869 | if (!entry) |
ea4e2bc4 SR |
4870 | return 0; |
4871 | ||
555fc781 | 4872 | if (entry == FTRACE_GRAPH_EMPTY) { |
280d1429 NK |
4873 | struct ftrace_graph_data *fgd = m->private; |
4874 | ||
b9b0c831 | 4875 | if (fgd->type == GRAPH_FILTER_FUNCTION) |
fa6f0cc7 | 4876 | seq_puts(m, "#### all functions enabled ####\n"); |
280d1429 | 4877 | else |
fa6f0cc7 | 4878 | seq_puts(m, "#### no functions disabled ####\n"); |
f9349a8f FW |
4879 | return 0; |
4880 | } | |
4881 | ||
b9b0c831 | 4882 | seq_printf(m, "%ps\n", (void *)entry->ip); |
ea4e2bc4 SR |
4883 | |
4884 | return 0; | |
4885 | } | |
4886 | ||
88e9d34c | 4887 | static const struct seq_operations ftrace_graph_seq_ops = { |
ea4e2bc4 SR |
4888 | .start = g_start, |
4889 | .next = g_next, | |
4890 | .stop = g_stop, | |
4891 | .show = g_show, | |
4892 | }; | |
4893 | ||
4894 | static int | |
faf982a6 NK |
4895 | __ftrace_graph_open(struct inode *inode, struct file *file, |
4896 | struct ftrace_graph_data *fgd) | |
ea4e2bc4 SR |
4897 | { |
4898 | int ret = 0; | |
b9b0c831 | 4899 | struct ftrace_hash *new_hash = NULL; |
ea4e2bc4 | 4900 | |
b9b0c831 NK |
4901 | if (file->f_mode & FMODE_WRITE) { |
4902 | const int size_bits = FTRACE_HASH_DEFAULT_BITS; | |
4903 | ||
e704eff3 SRV |
4904 | if (trace_parser_get_init(&fgd->parser, FTRACE_BUFF_MAX)) |
4905 | return -ENOMEM; | |
4906 | ||
b9b0c831 NK |
4907 | if (file->f_flags & O_TRUNC) |
4908 | new_hash = alloc_ftrace_hash(size_bits); | |
4909 | else | |
4910 | new_hash = alloc_and_copy_ftrace_hash(size_bits, | |
4911 | fgd->hash); | |
4912 | if (!new_hash) { | |
4913 | ret = -ENOMEM; | |
4914 | goto out; | |
4915 | } | |
ea4e2bc4 SR |
4916 | } |
4917 | ||
faf982a6 | 4918 | if (file->f_mode & FMODE_READ) { |
b9b0c831 | 4919 | ret = seq_open(file, &ftrace_graph_seq_ops); |
faf982a6 NK |
4920 | if (!ret) { |
4921 | struct seq_file *m = file->private_data; | |
4922 | m->private = fgd; | |
b9b0c831 NK |
4923 | } else { |
4924 | /* Failed */ | |
4925 | free_ftrace_hash(new_hash); | |
4926 | new_hash = NULL; | |
faf982a6 NK |
4927 | } |
4928 | } else | |
4929 | file->private_data = fgd; | |
ea4e2bc4 | 4930 | |
b9b0c831 | 4931 | out: |
e704eff3 SRV |
4932 | if (ret < 0 && file->f_mode & FMODE_WRITE) |
4933 | trace_parser_put(&fgd->parser); | |
4934 | ||
b9b0c831 | 4935 | fgd->new_hash = new_hash; |
649b988b SRV |
4936 | |
4937 | /* | |
4938 | * All uses of fgd->hash must be taken with the graph_lock | |
4939 | * held. The graph_lock is going to be released, so force | |
4940 | * fgd->hash to be reinitialized when it is taken again. | |
4941 | */ | |
4942 | fgd->hash = NULL; | |
4943 | ||
ea4e2bc4 SR |
4944 | return ret; |
4945 | } | |
4946 | ||
faf982a6 NK |
4947 | static int |
4948 | ftrace_graph_open(struct inode *inode, struct file *file) | |
4949 | { | |
4950 | struct ftrace_graph_data *fgd; | |
b9b0c831 | 4951 | int ret; |
faf982a6 NK |
4952 | |
4953 | if (unlikely(ftrace_disabled)) | |
4954 | return -ENODEV; | |
4955 | ||
4956 | fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); | |
4957 | if (fgd == NULL) | |
4958 | return -ENOMEM; | |
4959 | ||
b9b0c831 NK |
4960 | mutex_lock(&graph_lock); |
4961 | ||
649b988b SRV |
4962 | fgd->hash = rcu_dereference_protected(ftrace_graph_hash, |
4963 | lockdep_is_held(&graph_lock)); | |
b9b0c831 | 4964 | fgd->type = GRAPH_FILTER_FUNCTION; |
faf982a6 NK |
4965 | fgd->seq_ops = &ftrace_graph_seq_ops; |
4966 | ||
b9b0c831 NK |
4967 | ret = __ftrace_graph_open(inode, file, fgd); |
4968 | if (ret < 0) | |
4969 | kfree(fgd); | |
4970 | ||
4971 | mutex_unlock(&graph_lock); | |
4972 | return ret; | |
faf982a6 NK |
4973 | } |
4974 | ||
29ad23b0 NK |
4975 | static int |
4976 | ftrace_graph_notrace_open(struct inode *inode, struct file *file) | |
4977 | { | |
4978 | struct ftrace_graph_data *fgd; | |
b9b0c831 | 4979 | int ret; |
29ad23b0 NK |
4980 | |
4981 | if (unlikely(ftrace_disabled)) | |
4982 | return -ENODEV; | |
4983 | ||
4984 | fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); | |
4985 | if (fgd == NULL) | |
4986 | return -ENOMEM; | |
4987 | ||
b9b0c831 NK |
4988 | mutex_lock(&graph_lock); |
4989 | ||
649b988b SRV |
4990 | fgd->hash = rcu_dereference_protected(ftrace_graph_notrace_hash, |
4991 | lockdep_is_held(&graph_lock)); | |
b9b0c831 | 4992 | fgd->type = GRAPH_FILTER_NOTRACE; |
29ad23b0 NK |
4993 | fgd->seq_ops = &ftrace_graph_seq_ops; |
4994 | ||
b9b0c831 NK |
4995 | ret = __ftrace_graph_open(inode, file, fgd); |
4996 | if (ret < 0) | |
4997 | kfree(fgd); | |
4998 | ||
4999 | mutex_unlock(&graph_lock); | |
5000 | return ret; | |
29ad23b0 NK |
5001 | } |
5002 | ||
87827111 LZ |
5003 | static int |
5004 | ftrace_graph_release(struct inode *inode, struct file *file) | |
5005 | { | |
b9b0c831 | 5006 | struct ftrace_graph_data *fgd; |
e704eff3 SRV |
5007 | struct ftrace_hash *old_hash, *new_hash; |
5008 | struct trace_parser *parser; | |
5009 | int ret = 0; | |
b9b0c831 | 5010 | |
faf982a6 NK |
5011 | if (file->f_mode & FMODE_READ) { |
5012 | struct seq_file *m = file->private_data; | |
5013 | ||
b9b0c831 | 5014 | fgd = m->private; |
87827111 | 5015 | seq_release(inode, file); |
faf982a6 | 5016 | } else { |
b9b0c831 | 5017 | fgd = file->private_data; |
faf982a6 NK |
5018 | } |
5019 | ||
e704eff3 SRV |
5020 | |
5021 | if (file->f_mode & FMODE_WRITE) { | |
5022 | ||
5023 | parser = &fgd->parser; | |
5024 | ||
5025 | if (trace_parser_loaded((parser))) { | |
5026 | parser->buffer[parser->idx] = 0; | |
5027 | ret = ftrace_graph_set_hash(fgd->new_hash, | |
5028 | parser->buffer); | |
5029 | } | |
5030 | ||
5031 | trace_parser_put(parser); | |
5032 | ||
5033 | new_hash = __ftrace_hash_move(fgd->new_hash); | |
5034 | if (!new_hash) { | |
5035 | ret = -ENOMEM; | |
5036 | goto out; | |
5037 | } | |
5038 | ||
5039 | mutex_lock(&graph_lock); | |
5040 | ||
5041 | if (fgd->type == GRAPH_FILTER_FUNCTION) { | |
5042 | old_hash = rcu_dereference_protected(ftrace_graph_hash, | |
5043 | lockdep_is_held(&graph_lock)); | |
5044 | rcu_assign_pointer(ftrace_graph_hash, new_hash); | |
5045 | } else { | |
5046 | old_hash = rcu_dereference_protected(ftrace_graph_notrace_hash, | |
5047 | lockdep_is_held(&graph_lock)); | |
5048 | rcu_assign_pointer(ftrace_graph_notrace_hash, new_hash); | |
5049 | } | |
5050 | ||
5051 | mutex_unlock(&graph_lock); | |
5052 | ||
5053 | /* Wait till all users are no longer using the old hash */ | |
5054 | synchronize_sched(); | |
5055 | ||
5056 | free_ftrace_hash(old_hash); | |
5057 | } | |
5058 | ||
5059 | out: | |
b9b0c831 NK |
5060 | kfree(fgd->new_hash); |
5061 | kfree(fgd); | |
5062 | ||
e704eff3 | 5063 | return ret; |
87827111 LZ |
5064 | } |
5065 | ||
ea4e2bc4 | 5066 | static int |
b9b0c831 | 5067 | ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer) |
ea4e2bc4 | 5068 | { |
3ba00929 | 5069 | struct ftrace_glob func_g; |
ea4e2bc4 SR |
5070 | struct dyn_ftrace *rec; |
5071 | struct ftrace_page *pg; | |
b9b0c831 | 5072 | struct ftrace_func_entry *entry; |
c7c6b1fe | 5073 | int fail = 1; |
3ba00929 | 5074 | int not; |
ea4e2bc4 | 5075 | |
f9349a8f | 5076 | /* decode regex */ |
3ba00929 DS |
5077 | func_g.type = filter_parse_regex(buffer, strlen(buffer), |
5078 | &func_g.search, ¬); | |
f9349a8f | 5079 | |
3ba00929 | 5080 | func_g.len = strlen(func_g.search); |
f9349a8f | 5081 | |
52baf119 | 5082 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
5083 | |
5084 | if (unlikely(ftrace_disabled)) { | |
5085 | mutex_unlock(&ftrace_lock); | |
5086 | return -ENODEV; | |
5087 | } | |
5088 | ||
265c831c SR |
5089 | do_for_each_ftrace_rec(pg, rec) { |
5090 | ||
546fece4 SRRH |
5091 | if (rec->flags & FTRACE_FL_DISABLED) |
5092 | continue; | |
5093 | ||
0b507e1e | 5094 | if (ftrace_match_record(rec, &func_g, NULL, 0)) { |
b9b0c831 | 5095 | entry = ftrace_lookup_ip(hash, rec->ip); |
c7c6b1fe LZ |
5096 | |
5097 | if (!not) { | |
5098 | fail = 0; | |
b9b0c831 NK |
5099 | |
5100 | if (entry) | |
5101 | continue; | |
5102 | if (add_hash_entry(hash, rec->ip) < 0) | |
5103 | goto out; | |
c7c6b1fe | 5104 | } else { |
b9b0c831 NK |
5105 | if (entry) { |
5106 | free_hash_entry(hash, entry); | |
c7c6b1fe LZ |
5107 | fail = 0; |
5108 | } | |
5109 | } | |
ea4e2bc4 | 5110 | } |
265c831c | 5111 | } while_for_each_ftrace_rec(); |
c7c6b1fe | 5112 | out: |
52baf119 | 5113 | mutex_unlock(&ftrace_lock); |
ea4e2bc4 | 5114 | |
c7c6b1fe LZ |
5115 | if (fail) |
5116 | return -EINVAL; | |
5117 | ||
c7c6b1fe | 5118 | return 0; |
ea4e2bc4 SR |
5119 | } |
5120 | ||
5121 | static ssize_t | |
5122 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
5123 | size_t cnt, loff_t *ppos) | |
5124 | { | |
6a10108b | 5125 | ssize_t read, ret = 0; |
faf982a6 | 5126 | struct ftrace_graph_data *fgd = file->private_data; |
e704eff3 | 5127 | struct trace_parser *parser; |
ea4e2bc4 | 5128 | |
c7c6b1fe | 5129 | if (!cnt) |
ea4e2bc4 SR |
5130 | return 0; |
5131 | ||
ae98d27a SRV |
5132 | /* Read mode uses seq functions */ |
5133 | if (file->f_mode & FMODE_READ) { | |
5134 | struct seq_file *m = file->private_data; | |
5135 | fgd = m->private; | |
5136 | } | |
5137 | ||
e704eff3 | 5138 | parser = &fgd->parser; |
ea4e2bc4 | 5139 | |
e704eff3 | 5140 | read = trace_get_user(parser, ubuf, cnt, ppos); |
689fd8b6 | 5141 | |
e704eff3 SRV |
5142 | if (read >= 0 && trace_parser_loaded(parser) && |
5143 | !trace_parser_cont(parser)) { | |
6a10108b | 5144 | |
b9b0c831 | 5145 | ret = ftrace_graph_set_hash(fgd->new_hash, |
e704eff3 SRV |
5146 | parser->buffer); |
5147 | trace_parser_clear(parser); | |
ea4e2bc4 | 5148 | } |
ea4e2bc4 | 5149 | |
6a10108b NK |
5150 | if (!ret) |
5151 | ret = read; | |
1eb90f13 | 5152 | |
ea4e2bc4 SR |
5153 | return ret; |
5154 | } | |
5155 | ||
5156 | static const struct file_operations ftrace_graph_fops = { | |
87827111 LZ |
5157 | .open = ftrace_graph_open, |
5158 | .read = seq_read, | |
5159 | .write = ftrace_graph_write, | |
098c879e | 5160 | .llseek = tracing_lseek, |
87827111 | 5161 | .release = ftrace_graph_release, |
ea4e2bc4 | 5162 | }; |
29ad23b0 NK |
5163 | |
5164 | static const struct file_operations ftrace_graph_notrace_fops = { | |
5165 | .open = ftrace_graph_notrace_open, | |
5166 | .read = seq_read, | |
5167 | .write = ftrace_graph_write, | |
098c879e | 5168 | .llseek = tracing_lseek, |
29ad23b0 NK |
5169 | .release = ftrace_graph_release, |
5170 | }; | |
ea4e2bc4 SR |
5171 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
5172 | ||
591dffda SRRH |
5173 | void ftrace_create_filter_files(struct ftrace_ops *ops, |
5174 | struct dentry *parent) | |
5175 | { | |
5176 | ||
5177 | trace_create_file("set_ftrace_filter", 0644, parent, | |
5178 | ops, &ftrace_filter_fops); | |
5179 | ||
5180 | trace_create_file("set_ftrace_notrace", 0644, parent, | |
5181 | ops, &ftrace_notrace_fops); | |
5182 | } | |
5183 | ||
5184 | /* | |
5185 | * The name "destroy_filter_files" is really a misnomer. Although | |
5186 | * in the future, it may actualy delete the files, but this is | |
5187 | * really intended to make sure the ops passed in are disabled | |
5188 | * and that when this function returns, the caller is free to | |
5189 | * free the ops. | |
5190 | * | |
5191 | * The "destroy" name is only to match the "create" name that this | |
5192 | * should be paired with. | |
5193 | */ | |
5194 | void ftrace_destroy_filter_files(struct ftrace_ops *ops) | |
5195 | { | |
5196 | mutex_lock(&ftrace_lock); | |
5197 | if (ops->flags & FTRACE_OPS_FL_ENABLED) | |
5198 | ftrace_shutdown(ops, 0); | |
5199 | ops->flags |= FTRACE_OPS_FL_DELETED; | |
5200 | mutex_unlock(&ftrace_lock); | |
5201 | } | |
5202 | ||
8434dc93 | 5203 | static __init int ftrace_init_dyn_tracefs(struct dentry *d_tracer) |
5072c59f | 5204 | { |
5072c59f | 5205 | |
5452af66 FW |
5206 | trace_create_file("available_filter_functions", 0444, |
5207 | d_tracer, NULL, &ftrace_avail_fops); | |
5072c59f | 5208 | |
647bcd03 SR |
5209 | trace_create_file("enabled_functions", 0444, |
5210 | d_tracer, NULL, &ftrace_enabled_fops); | |
5211 | ||
591dffda | 5212 | ftrace_create_filter_files(&global_ops, d_tracer); |
ad90c0e3 | 5213 | |
ea4e2bc4 | 5214 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5452af66 | 5215 | trace_create_file("set_graph_function", 0444, d_tracer, |
ea4e2bc4 SR |
5216 | NULL, |
5217 | &ftrace_graph_fops); | |
29ad23b0 NK |
5218 | trace_create_file("set_graph_notrace", 0444, d_tracer, |
5219 | NULL, | |
5220 | &ftrace_graph_notrace_fops); | |
ea4e2bc4 SR |
5221 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
5222 | ||
5072c59f SR |
5223 | return 0; |
5224 | } | |
5225 | ||
9fd49328 | 5226 | static int ftrace_cmp_ips(const void *a, const void *b) |
68950619 | 5227 | { |
9fd49328 SR |
5228 | const unsigned long *ipa = a; |
5229 | const unsigned long *ipb = b; | |
68950619 | 5230 | |
9fd49328 SR |
5231 | if (*ipa > *ipb) |
5232 | return 1; | |
5233 | if (*ipa < *ipb) | |
5234 | return -1; | |
5235 | return 0; | |
5236 | } | |
5237 | ||
5cb084bb | 5238 | static int ftrace_process_locs(struct module *mod, |
31e88909 | 5239 | unsigned long *start, |
68bf21aa SR |
5240 | unsigned long *end) |
5241 | { | |
706c81f8 | 5242 | struct ftrace_page *start_pg; |
a7900875 | 5243 | struct ftrace_page *pg; |
706c81f8 | 5244 | struct dyn_ftrace *rec; |
a7900875 | 5245 | unsigned long count; |
68bf21aa SR |
5246 | unsigned long *p; |
5247 | unsigned long addr; | |
4376cac6 | 5248 | unsigned long flags = 0; /* Shut up gcc */ |
a7900875 SR |
5249 | int ret = -ENOMEM; |
5250 | ||
5251 | count = end - start; | |
5252 | ||
5253 | if (!count) | |
5254 | return 0; | |
5255 | ||
9fd49328 | 5256 | sort(start, count, sizeof(*start), |
6db02903 | 5257 | ftrace_cmp_ips, NULL); |
9fd49328 | 5258 | |
706c81f8 SR |
5259 | start_pg = ftrace_allocate_pages(count); |
5260 | if (!start_pg) | |
a7900875 | 5261 | return -ENOMEM; |
68bf21aa | 5262 | |
e6ea44e9 | 5263 | mutex_lock(&ftrace_lock); |
a7900875 | 5264 | |
32082309 SR |
5265 | /* |
5266 | * Core and each module needs their own pages, as | |
5267 | * modules will free them when they are removed. | |
5268 | * Force a new page to be allocated for modules. | |
5269 | */ | |
a7900875 SR |
5270 | if (!mod) { |
5271 | WARN_ON(ftrace_pages || ftrace_pages_start); | |
5272 | /* First initialization */ | |
706c81f8 | 5273 | ftrace_pages = ftrace_pages_start = start_pg; |
a7900875 | 5274 | } else { |
32082309 | 5275 | if (!ftrace_pages) |
a7900875 | 5276 | goto out; |
32082309 | 5277 | |
a7900875 SR |
5278 | if (WARN_ON(ftrace_pages->next)) { |
5279 | /* Hmm, we have free pages? */ | |
5280 | while (ftrace_pages->next) | |
5281 | ftrace_pages = ftrace_pages->next; | |
32082309 | 5282 | } |
a7900875 | 5283 | |
706c81f8 | 5284 | ftrace_pages->next = start_pg; |
32082309 SR |
5285 | } |
5286 | ||
68bf21aa | 5287 | p = start; |
706c81f8 | 5288 | pg = start_pg; |
68bf21aa SR |
5289 | while (p < end) { |
5290 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
5291 | /* |
5292 | * Some architecture linkers will pad between | |
5293 | * the different mcount_loc sections of different | |
5294 | * object files to satisfy alignments. | |
5295 | * Skip any NULL pointers. | |
5296 | */ | |
5297 | if (!addr) | |
5298 | continue; | |
706c81f8 SR |
5299 | |
5300 | if (pg->index == pg->size) { | |
5301 | /* We should have allocated enough */ | |
5302 | if (WARN_ON(!pg->next)) | |
5303 | break; | |
5304 | pg = pg->next; | |
5305 | } | |
5306 | ||
5307 | rec = &pg->records[pg->index++]; | |
5308 | rec->ip = addr; | |
68bf21aa SR |
5309 | } |
5310 | ||
706c81f8 SR |
5311 | /* We should have used all pages */ |
5312 | WARN_ON(pg->next); | |
5313 | ||
5314 | /* Assign the last page to ftrace_pages */ | |
5315 | ftrace_pages = pg; | |
5316 | ||
a4f18ed1 | 5317 | /* |
4376cac6 SR |
5318 | * We only need to disable interrupts on start up |
5319 | * because we are modifying code that an interrupt | |
5320 | * may execute, and the modification is not atomic. | |
5321 | * But for modules, nothing runs the code we modify | |
5322 | * until we are finished with it, and there's no | |
5323 | * reason to cause large interrupt latencies while we do it. | |
a4f18ed1 | 5324 | */ |
4376cac6 SR |
5325 | if (!mod) |
5326 | local_irq_save(flags); | |
1dc43cf0 | 5327 | ftrace_update_code(mod, start_pg); |
4376cac6 SR |
5328 | if (!mod) |
5329 | local_irq_restore(flags); | |
a7900875 SR |
5330 | ret = 0; |
5331 | out: | |
e6ea44e9 | 5332 | mutex_unlock(&ftrace_lock); |
68bf21aa | 5333 | |
a7900875 | 5334 | return ret; |
68bf21aa SR |
5335 | } |
5336 | ||
93eb677d | 5337 | #ifdef CONFIG_MODULES |
32082309 SR |
5338 | |
5339 | #define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next) | |
5340 | ||
b7ffffbb SRRH |
5341 | static int referenced_filters(struct dyn_ftrace *rec) |
5342 | { | |
5343 | struct ftrace_ops *ops; | |
5344 | int cnt = 0; | |
5345 | ||
5346 | for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) { | |
5347 | if (ops_references_rec(ops, rec)) | |
5348 | cnt++; | |
5349 | } | |
5350 | ||
5351 | return cnt; | |
5352 | } | |
5353 | ||
e7247a15 | 5354 | void ftrace_release_mod(struct module *mod) |
93eb677d SR |
5355 | { |
5356 | struct dyn_ftrace *rec; | |
32082309 | 5357 | struct ftrace_page **last_pg; |
93eb677d | 5358 | struct ftrace_page *pg; |
a7900875 | 5359 | int order; |
93eb677d | 5360 | |
45a4a237 SR |
5361 | mutex_lock(&ftrace_lock); |
5362 | ||
e7247a15 | 5363 | if (ftrace_disabled) |
45a4a237 | 5364 | goto out_unlock; |
93eb677d | 5365 | |
32082309 SR |
5366 | /* |
5367 | * Each module has its own ftrace_pages, remove | |
5368 | * them from the list. | |
5369 | */ | |
5370 | last_pg = &ftrace_pages_start; | |
5371 | for (pg = ftrace_pages_start; pg; pg = *last_pg) { | |
5372 | rec = &pg->records[0]; | |
e7247a15 | 5373 | if (within_module_core(rec->ip, mod)) { |
93eb677d | 5374 | /* |
32082309 SR |
5375 | * As core pages are first, the first |
5376 | * page should never be a module page. | |
93eb677d | 5377 | */ |
32082309 SR |
5378 | if (WARN_ON(pg == ftrace_pages_start)) |
5379 | goto out_unlock; | |
5380 | ||
5381 | /* Check if we are deleting the last page */ | |
5382 | if (pg == ftrace_pages) | |
5383 | ftrace_pages = next_to_ftrace_page(last_pg); | |
5384 | ||
5385 | *last_pg = pg->next; | |
a7900875 SR |
5386 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); |
5387 | free_pages((unsigned long)pg->records, order); | |
5388 | kfree(pg); | |
32082309 SR |
5389 | } else |
5390 | last_pg = &pg->next; | |
5391 | } | |
45a4a237 | 5392 | out_unlock: |
93eb677d SR |
5393 | mutex_unlock(&ftrace_lock); |
5394 | } | |
5395 | ||
7dcd182b | 5396 | void ftrace_module_enable(struct module *mod) |
b7ffffbb SRRH |
5397 | { |
5398 | struct dyn_ftrace *rec; | |
5399 | struct ftrace_page *pg; | |
5400 | ||
5401 | mutex_lock(&ftrace_lock); | |
5402 | ||
5403 | if (ftrace_disabled) | |
5404 | goto out_unlock; | |
5405 | ||
5406 | /* | |
5407 | * If the tracing is enabled, go ahead and enable the record. | |
5408 | * | |
5409 | * The reason not to enable the record immediatelly is the | |
5410 | * inherent check of ftrace_make_nop/ftrace_make_call for | |
5411 | * correct previous instructions. Making first the NOP | |
5412 | * conversion puts the module to the correct state, thus | |
5413 | * passing the ftrace_make_call check. | |
5414 | * | |
5415 | * We also delay this to after the module code already set the | |
5416 | * text to read-only, as we now need to set it back to read-write | |
5417 | * so that we can modify the text. | |
5418 | */ | |
5419 | if (ftrace_start_up) | |
5420 | ftrace_arch_code_modify_prepare(); | |
5421 | ||
5422 | do_for_each_ftrace_rec(pg, rec) { | |
5423 | int cnt; | |
5424 | /* | |
5425 | * do_for_each_ftrace_rec() is a double loop. | |
5426 | * module text shares the pg. If a record is | |
5427 | * not part of this module, then skip this pg, | |
5428 | * which the "break" will do. | |
5429 | */ | |
5430 | if (!within_module_core(rec->ip, mod)) | |
5431 | break; | |
5432 | ||
5433 | cnt = 0; | |
5434 | ||
5435 | /* | |
5436 | * When adding a module, we need to check if tracers are | |
5437 | * currently enabled and if they are, and can trace this record, | |
5438 | * we need to enable the module functions as well as update the | |
5439 | * reference counts for those function records. | |
5440 | */ | |
5441 | if (ftrace_start_up) | |
5442 | cnt += referenced_filters(rec); | |
5443 | ||
5444 | /* This clears FTRACE_FL_DISABLED */ | |
5445 | rec->flags = cnt; | |
5446 | ||
5447 | if (ftrace_start_up && cnt) { | |
5448 | int failed = __ftrace_replace_code(rec, 1); | |
5449 | if (failed) { | |
5450 | ftrace_bug(failed, rec); | |
5451 | goto out_loop; | |
5452 | } | |
5453 | } | |
5454 | ||
5455 | } while_for_each_ftrace_rec(); | |
5456 | ||
5457 | out_loop: | |
5458 | if (ftrace_start_up) | |
5459 | ftrace_arch_code_modify_post_process(); | |
5460 | ||
5461 | out_unlock: | |
5462 | mutex_unlock(&ftrace_lock); | |
5463 | } | |
5464 | ||
b6b71f66 | 5465 | void ftrace_module_init(struct module *mod) |
90d595fe | 5466 | { |
97e9b4fc | 5467 | if (ftrace_disabled || !mod->num_ftrace_callsites) |
fed1939c | 5468 | return; |
90d595fe | 5469 | |
97e9b4fc SRRH |
5470 | ftrace_process_locs(mod, mod->ftrace_callsites, |
5471 | mod->ftrace_callsites + mod->num_ftrace_callsites); | |
8c189ea6 | 5472 | } |
93eb677d SR |
5473 | #endif /* CONFIG_MODULES */ |
5474 | ||
b80f0f6c | 5475 | void __init ftrace_free_init_mem(void) |
42c269c8 | 5476 | { |
b80f0f6c SRV |
5477 | unsigned long start = (unsigned long)(&__init_begin); |
5478 | unsigned long end = (unsigned long)(&__init_end); | |
42c269c8 SRV |
5479 | struct ftrace_page **last_pg = &ftrace_pages_start; |
5480 | struct ftrace_page *pg; | |
5481 | struct dyn_ftrace *rec; | |
5482 | struct dyn_ftrace key; | |
5483 | int order; | |
5484 | ||
5485 | key.ip = start; | |
5486 | key.flags = end; /* overload flags, as it is unsigned long */ | |
5487 | ||
5488 | mutex_lock(&ftrace_lock); | |
5489 | ||
5490 | for (pg = ftrace_pages_start; pg; last_pg = &pg->next, pg = *last_pg) { | |
5491 | if (end < pg->records[0].ip || | |
5492 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) | |
5493 | continue; | |
5494 | again: | |
5495 | rec = bsearch(&key, pg->records, pg->index, | |
5496 | sizeof(struct dyn_ftrace), | |
5497 | ftrace_cmp_recs); | |
5498 | if (!rec) | |
5499 | continue; | |
5500 | pg->index--; | |
5501 | if (!pg->index) { | |
5502 | *last_pg = pg->next; | |
5503 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); | |
5504 | free_pages((unsigned long)pg->records, order); | |
5505 | kfree(pg); | |
5506 | pg = container_of(last_pg, struct ftrace_page, next); | |
5507 | if (!(*last_pg)) | |
5508 | ftrace_pages = pg; | |
5509 | continue; | |
5510 | } | |
5511 | memmove(rec, rec + 1, | |
5512 | (pg->index - (rec - pg->records)) * sizeof(*rec)); | |
5513 | /* More than one function may be in this block */ | |
5514 | goto again; | |
5515 | } | |
5516 | mutex_unlock(&ftrace_lock); | |
5517 | } | |
5518 | ||
68bf21aa SR |
5519 | void __init ftrace_init(void) |
5520 | { | |
1dc43cf0 JS |
5521 | extern unsigned long __start_mcount_loc[]; |
5522 | extern unsigned long __stop_mcount_loc[]; | |
3a36cb11 | 5523 | unsigned long count, flags; |
68bf21aa SR |
5524 | int ret; |
5525 | ||
68bf21aa | 5526 | local_irq_save(flags); |
3a36cb11 | 5527 | ret = ftrace_dyn_arch_init(); |
68bf21aa | 5528 | local_irq_restore(flags); |
af64a7cb | 5529 | if (ret) |
68bf21aa SR |
5530 | goto failed; |
5531 | ||
5532 | count = __stop_mcount_loc - __start_mcount_loc; | |
c867ccd8 JS |
5533 | if (!count) { |
5534 | pr_info("ftrace: No functions to be traced?\n"); | |
68bf21aa | 5535 | goto failed; |
c867ccd8 JS |
5536 | } |
5537 | ||
5538 | pr_info("ftrace: allocating %ld entries in %ld pages\n", | |
5539 | count, count / ENTRIES_PER_PAGE + 1); | |
68bf21aa SR |
5540 | |
5541 | last_ftrace_enabled = ftrace_enabled = 1; | |
5542 | ||
5cb084bb | 5543 | ret = ftrace_process_locs(NULL, |
31e88909 | 5544 | __start_mcount_loc, |
68bf21aa SR |
5545 | __stop_mcount_loc); |
5546 | ||
2af15d6a SR |
5547 | set_ftrace_early_filters(); |
5548 | ||
68bf21aa SR |
5549 | return; |
5550 | failed: | |
5551 | ftrace_disabled = 1; | |
5552 | } | |
68bf21aa | 5553 | |
f3bea491 SRRH |
5554 | /* Do nothing if arch does not support this */ |
5555 | void __weak arch_ftrace_update_trampoline(struct ftrace_ops *ops) | |
5556 | { | |
5557 | } | |
5558 | ||
5559 | static void ftrace_update_trampoline(struct ftrace_ops *ops) | |
5560 | { | |
f3bea491 SRRH |
5561 | arch_ftrace_update_trampoline(ops); |
5562 | } | |
5563 | ||
04ec7bb6 SRV |
5564 | void ftrace_init_trace_array(struct trace_array *tr) |
5565 | { | |
5566 | INIT_LIST_HEAD(&tr->func_probes); | |
5567 | } | |
3d083395 | 5568 | #else |
0b6e4d56 | 5569 | |
2b499381 | 5570 | static struct ftrace_ops global_ops = { |
bd69c30b | 5571 | .func = ftrace_stub, |
e3eea140 SRRH |
5572 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | |
5573 | FTRACE_OPS_FL_INITIALIZED | | |
5574 | FTRACE_OPS_FL_PID, | |
bd69c30b SR |
5575 | }; |
5576 | ||
0b6e4d56 FW |
5577 | static int __init ftrace_nodyn_init(void) |
5578 | { | |
5579 | ftrace_enabled = 1; | |
5580 | return 0; | |
5581 | } | |
6f415672 | 5582 | core_initcall(ftrace_nodyn_init); |
0b6e4d56 | 5583 | |
8434dc93 | 5584 | static inline int ftrace_init_dyn_tracefs(struct dentry *d_tracer) { return 0; } |
df4fc315 | 5585 | static inline void ftrace_startup_enable(int command) { } |
e1effa01 | 5586 | static inline void ftrace_startup_all(int command) { } |
5a45cfe1 | 5587 | /* Keep as macros so we do not need to define the commands */ |
8a56d776 SRRH |
5588 | # define ftrace_startup(ops, command) \ |
5589 | ({ \ | |
5590 | int ___ret = __register_ftrace_function(ops); \ | |
5591 | if (!___ret) \ | |
5592 | (ops)->flags |= FTRACE_OPS_FL_ENABLED; \ | |
5593 | ___ret; \ | |
3b6cfdb1 | 5594 | }) |
1fcc1553 SRRH |
5595 | # define ftrace_shutdown(ops, command) \ |
5596 | ({ \ | |
5597 | int ___ret = __unregister_ftrace_function(ops); \ | |
5598 | if (!___ret) \ | |
5599 | (ops)->flags &= ~FTRACE_OPS_FL_ENABLED; \ | |
5600 | ___ret; \ | |
5601 | }) | |
8a56d776 | 5602 | |
c7aafc54 IM |
5603 | # define ftrace_startup_sysctl() do { } while (0) |
5604 | # define ftrace_shutdown_sysctl() do { } while (0) | |
b848914c SR |
5605 | |
5606 | static inline int | |
195a8afc | 5607 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs) |
b848914c SR |
5608 | { |
5609 | return 1; | |
5610 | } | |
5611 | ||
f3bea491 SRRH |
5612 | static void ftrace_update_trampoline(struct ftrace_ops *ops) |
5613 | { | |
5614 | } | |
5615 | ||
3d083395 SR |
5616 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
5617 | ||
4104d326 SRRH |
5618 | __init void ftrace_init_global_array_ops(struct trace_array *tr) |
5619 | { | |
5620 | tr->ops = &global_ops; | |
5621 | tr->ops->private = tr; | |
04ec7bb6 | 5622 | ftrace_init_trace_array(tr); |
4104d326 SRRH |
5623 | } |
5624 | ||
5625 | void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func) | |
5626 | { | |
5627 | /* If we filter on pids, update to use the pid function */ | |
5628 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { | |
5629 | if (WARN_ON(tr->ops->func != ftrace_stub)) | |
5630 | printk("ftrace ops had %pS for function\n", | |
5631 | tr->ops->func); | |
4104d326 SRRH |
5632 | } |
5633 | tr->ops->func = func; | |
5634 | tr->ops->private = tr; | |
5635 | } | |
5636 | ||
5637 | void ftrace_reset_array_ops(struct trace_array *tr) | |
5638 | { | |
5639 | tr->ops->func = ftrace_stub; | |
5640 | } | |
5641 | ||
2f5f6ad9 SR |
5642 | static inline void |
5643 | __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 5644 | struct ftrace_ops *ignored, struct pt_regs *regs) |
b848914c | 5645 | { |
cdbe61bf | 5646 | struct ftrace_ops *op; |
edc15caf | 5647 | int bit; |
b848914c | 5648 | |
edc15caf SR |
5649 | bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); |
5650 | if (bit < 0) | |
5651 | return; | |
b1cff0ad | 5652 | |
cdbe61bf SR |
5653 | /* |
5654 | * Some of the ops may be dynamically allocated, | |
5655 | * they must be freed after a synchronize_sched(). | |
5656 | */ | |
5657 | preempt_disable_notrace(); | |
ba27f2bc | 5658 | |
0a016409 | 5659 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
ba27f2bc SRRH |
5660 | /* |
5661 | * Check the following for each ops before calling their func: | |
5662 | * if RCU flag is set, then rcu_is_watching() must be true | |
5663 | * if PER_CPU is set, then ftrace_function_local_disable() | |
5664 | * must be false | |
5665 | * Otherwise test if the ip matches the ops filter | |
5666 | * | |
5667 | * If any of the above fails then the op->func() is not executed. | |
5668 | */ | |
5669 | if ((!(op->flags & FTRACE_OPS_FL_RCU) || rcu_is_watching()) && | |
5670 | (!(op->flags & FTRACE_OPS_FL_PER_CPU) || | |
5671 | !ftrace_function_local_disabled(op)) && | |
5672 | ftrace_ops_test(op, ip, regs)) { | |
5673 | ||
1d48d596 SRRH |
5674 | if (FTRACE_WARN_ON(!op->func)) { |
5675 | pr_warn("op=%p %pS\n", op, op); | |
4104d326 SRRH |
5676 | goto out; |
5677 | } | |
a1e2e31d | 5678 | op->func(ip, parent_ip, op, regs); |
4104d326 | 5679 | } |
0a016409 | 5680 | } while_for_each_ftrace_op(op); |
4104d326 | 5681 | out: |
cdbe61bf | 5682 | preempt_enable_notrace(); |
edc15caf | 5683 | trace_clear_recursion(bit); |
b848914c SR |
5684 | } |
5685 | ||
2f5f6ad9 SR |
5686 | /* |
5687 | * Some archs only support passing ip and parent_ip. Even though | |
5688 | * the list function ignores the op parameter, we do not want any | |
5689 | * C side effects, where a function is called without the caller | |
5690 | * sending a third parameter. | |
a1e2e31d SR |
5691 | * Archs are to support both the regs and ftrace_ops at the same time. |
5692 | * If they support ftrace_ops, it is assumed they support regs. | |
5693 | * If call backs want to use regs, they must either check for regs | |
06aeaaea MH |
5694 | * being NULL, or CONFIG_DYNAMIC_FTRACE_WITH_REGS. |
5695 | * Note, CONFIG_DYNAMIC_FTRACE_WITH_REGS expects a full regs to be saved. | |
a1e2e31d | 5696 | * An architecture can pass partial regs with ftrace_ops and still |
b8ec330a | 5697 | * set the ARCH_SUPPORTS_FTRACE_OPS. |
2f5f6ad9 SR |
5698 | */ |
5699 | #if ARCH_SUPPORTS_FTRACE_OPS | |
5700 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 5701 | struct ftrace_ops *op, struct pt_regs *regs) |
2f5f6ad9 | 5702 | { |
a1e2e31d | 5703 | __ftrace_ops_list_func(ip, parent_ip, NULL, regs); |
2f5f6ad9 SR |
5704 | } |
5705 | #else | |
5706 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip) | |
5707 | { | |
a1e2e31d | 5708 | __ftrace_ops_list_func(ip, parent_ip, NULL, NULL); |
2f5f6ad9 SR |
5709 | } |
5710 | #endif | |
5711 | ||
f1ff6348 SRRH |
5712 | /* |
5713 | * If there's only one function registered but it does not support | |
c68c0fa2 SRRH |
5714 | * recursion, needs RCU protection and/or requires per cpu handling, then |
5715 | * this function will be called by the mcount trampoline. | |
f1ff6348 | 5716 | */ |
c68c0fa2 | 5717 | static void ftrace_ops_assist_func(unsigned long ip, unsigned long parent_ip, |
f1ff6348 SRRH |
5718 | struct ftrace_ops *op, struct pt_regs *regs) |
5719 | { | |
5720 | int bit; | |
5721 | ||
c68c0fa2 SRRH |
5722 | if ((op->flags & FTRACE_OPS_FL_RCU) && !rcu_is_watching()) |
5723 | return; | |
5724 | ||
f1ff6348 SRRH |
5725 | bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); |
5726 | if (bit < 0) | |
5727 | return; | |
5728 | ||
c68c0fa2 | 5729 | preempt_disable_notrace(); |
f1ff6348 | 5730 | |
c68c0fa2 SRRH |
5731 | if (!(op->flags & FTRACE_OPS_FL_PER_CPU) || |
5732 | !ftrace_function_local_disabled(op)) { | |
5733 | op->func(ip, parent_ip, op, regs); | |
5734 | } | |
5735 | ||
5736 | preempt_enable_notrace(); | |
f1ff6348 SRRH |
5737 | trace_clear_recursion(bit); |
5738 | } | |
5739 | ||
87354059 SRRH |
5740 | /** |
5741 | * ftrace_ops_get_func - get the function a trampoline should call | |
5742 | * @ops: the ops to get the function for | |
5743 | * | |
5744 | * Normally the mcount trampoline will call the ops->func, but there | |
5745 | * are times that it should not. For example, if the ops does not | |
5746 | * have its own recursion protection, then it should call the | |
3a150df9 | 5747 | * ftrace_ops_assist_func() instead. |
87354059 SRRH |
5748 | * |
5749 | * Returns the function that the trampoline should call for @ops. | |
5750 | */ | |
5751 | ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops) | |
5752 | { | |
87354059 | 5753 | /* |
c68c0fa2 SRRH |
5754 | * If the function does not handle recursion, needs to be RCU safe, |
5755 | * or does per cpu logic, then we need to call the assist handler. | |
87354059 | 5756 | */ |
c68c0fa2 SRRH |
5757 | if (!(ops->flags & FTRACE_OPS_FL_RECURSION_SAFE) || |
5758 | ops->flags & (FTRACE_OPS_FL_RCU | FTRACE_OPS_FL_PER_CPU)) | |
5759 | return ftrace_ops_assist_func; | |
87354059 SRRH |
5760 | |
5761 | return ops->func; | |
5762 | } | |
5763 | ||
345ddcc8 SRRH |
5764 | static void |
5765 | ftrace_filter_pid_sched_switch_probe(void *data, bool preempt, | |
5766 | struct task_struct *prev, struct task_struct *next) | |
978f3a45 | 5767 | { |
345ddcc8 SRRH |
5768 | struct trace_array *tr = data; |
5769 | struct trace_pid_list *pid_list; | |
978f3a45 | 5770 | |
345ddcc8 | 5771 | pid_list = rcu_dereference_sched(tr->function_pids); |
e32d8956 | 5772 | |
345ddcc8 SRRH |
5773 | this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid, |
5774 | trace_ignore_this_task(pid_list, next)); | |
978f3a45 SR |
5775 | } |
5776 | ||
1e10486f NK |
5777 | static void |
5778 | ftrace_pid_follow_sched_process_fork(void *data, | |
5779 | struct task_struct *self, | |
5780 | struct task_struct *task) | |
5781 | { | |
5782 | struct trace_pid_list *pid_list; | |
5783 | struct trace_array *tr = data; | |
5784 | ||
5785 | pid_list = rcu_dereference_sched(tr->function_pids); | |
5786 | trace_filter_add_remove_task(pid_list, self, task); | |
5787 | } | |
5788 | ||
5789 | static void | |
5790 | ftrace_pid_follow_sched_process_exit(void *data, struct task_struct *task) | |
5791 | { | |
5792 | struct trace_pid_list *pid_list; | |
5793 | struct trace_array *tr = data; | |
5794 | ||
5795 | pid_list = rcu_dereference_sched(tr->function_pids); | |
5796 | trace_filter_add_remove_task(pid_list, NULL, task); | |
5797 | } | |
5798 | ||
5799 | void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) | |
5800 | { | |
5801 | if (enable) { | |
5802 | register_trace_sched_process_fork(ftrace_pid_follow_sched_process_fork, | |
5803 | tr); | |
5804 | register_trace_sched_process_exit(ftrace_pid_follow_sched_process_exit, | |
5805 | tr); | |
5806 | } else { | |
5807 | unregister_trace_sched_process_fork(ftrace_pid_follow_sched_process_fork, | |
5808 | tr); | |
5809 | unregister_trace_sched_process_exit(ftrace_pid_follow_sched_process_exit, | |
5810 | tr); | |
5811 | } | |
5812 | } | |
5813 | ||
345ddcc8 | 5814 | static void clear_ftrace_pids(struct trace_array *tr) |
e32d8956 | 5815 | { |
345ddcc8 SRRH |
5816 | struct trace_pid_list *pid_list; |
5817 | int cpu; | |
e32d8956 | 5818 | |
345ddcc8 SRRH |
5819 | pid_list = rcu_dereference_protected(tr->function_pids, |
5820 | lockdep_is_held(&ftrace_lock)); | |
5821 | if (!pid_list) | |
5822 | return; | |
229c4ef8 | 5823 | |
345ddcc8 | 5824 | unregister_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr); |
e32d8956 | 5825 | |
345ddcc8 SRRH |
5826 | for_each_possible_cpu(cpu) |
5827 | per_cpu_ptr(tr->trace_buffer.data, cpu)->ftrace_ignore_pid = false; | |
978f3a45 | 5828 | |
345ddcc8 | 5829 | rcu_assign_pointer(tr->function_pids, NULL); |
978f3a45 | 5830 | |
345ddcc8 SRRH |
5831 | /* Wait till all users are no longer using pid filtering */ |
5832 | synchronize_sched(); | |
e32d8956 | 5833 | |
345ddcc8 | 5834 | trace_free_pid_list(pid_list); |
e32d8956 SR |
5835 | } |
5836 | ||
d879d0b8 NK |
5837 | void ftrace_clear_pids(struct trace_array *tr) |
5838 | { | |
5839 | mutex_lock(&ftrace_lock); | |
5840 | ||
5841 | clear_ftrace_pids(tr); | |
5842 | ||
5843 | mutex_unlock(&ftrace_lock); | |
5844 | } | |
5845 | ||
345ddcc8 | 5846 | static void ftrace_pid_reset(struct trace_array *tr) |
df4fc315 | 5847 | { |
756d17ee | 5848 | mutex_lock(&ftrace_lock); |
345ddcc8 | 5849 | clear_ftrace_pids(tr); |
978f3a45 | 5850 | |
756d17ee | 5851 | ftrace_update_pid_func(); |
e1effa01 | 5852 | ftrace_startup_all(0); |
756d17ee | 5853 | |
5854 | mutex_unlock(&ftrace_lock); | |
756d17ee | 5855 | } |
5856 | ||
345ddcc8 SRRH |
5857 | /* Greater than any max PID */ |
5858 | #define FTRACE_NO_PIDS (void *)(PID_MAX_LIMIT + 1) | |
df4fc315 | 5859 | |
756d17ee | 5860 | static void *fpid_start(struct seq_file *m, loff_t *pos) |
345ddcc8 | 5861 | __acquires(RCU) |
756d17ee | 5862 | { |
345ddcc8 SRRH |
5863 | struct trace_pid_list *pid_list; |
5864 | struct trace_array *tr = m->private; | |
5865 | ||
756d17ee | 5866 | mutex_lock(&ftrace_lock); |
345ddcc8 SRRH |
5867 | rcu_read_lock_sched(); |
5868 | ||
5869 | pid_list = rcu_dereference_sched(tr->function_pids); | |
756d17ee | 5870 | |
345ddcc8 SRRH |
5871 | if (!pid_list) |
5872 | return !(*pos) ? FTRACE_NO_PIDS : NULL; | |
756d17ee | 5873 | |
345ddcc8 | 5874 | return trace_pid_start(pid_list, pos); |
756d17ee | 5875 | } |
5876 | ||
5877 | static void *fpid_next(struct seq_file *m, void *v, loff_t *pos) | |
5878 | { | |
345ddcc8 SRRH |
5879 | struct trace_array *tr = m->private; |
5880 | struct trace_pid_list *pid_list = rcu_dereference_sched(tr->function_pids); | |
5881 | ||
5882 | if (v == FTRACE_NO_PIDS) | |
756d17ee | 5883 | return NULL; |
5884 | ||
345ddcc8 | 5885 | return trace_pid_next(pid_list, v, pos); |
756d17ee | 5886 | } |
5887 | ||
5888 | static void fpid_stop(struct seq_file *m, void *p) | |
345ddcc8 | 5889 | __releases(RCU) |
756d17ee | 5890 | { |
345ddcc8 | 5891 | rcu_read_unlock_sched(); |
756d17ee | 5892 | mutex_unlock(&ftrace_lock); |
5893 | } | |
5894 | ||
5895 | static int fpid_show(struct seq_file *m, void *v) | |
5896 | { | |
345ddcc8 | 5897 | if (v == FTRACE_NO_PIDS) { |
fa6f0cc7 | 5898 | seq_puts(m, "no pid\n"); |
756d17ee | 5899 | return 0; |
5900 | } | |
5901 | ||
345ddcc8 | 5902 | return trace_pid_show(m, v); |
756d17ee | 5903 | } |
5904 | ||
5905 | static const struct seq_operations ftrace_pid_sops = { | |
5906 | .start = fpid_start, | |
5907 | .next = fpid_next, | |
5908 | .stop = fpid_stop, | |
5909 | .show = fpid_show, | |
5910 | }; | |
5911 | ||
5912 | static int | |
5913 | ftrace_pid_open(struct inode *inode, struct file *file) | |
5914 | { | |
345ddcc8 SRRH |
5915 | struct trace_array *tr = inode->i_private; |
5916 | struct seq_file *m; | |
756d17ee | 5917 | int ret = 0; |
5918 | ||
345ddcc8 SRRH |
5919 | if (trace_array_get(tr) < 0) |
5920 | return -ENODEV; | |
5921 | ||
756d17ee | 5922 | if ((file->f_mode & FMODE_WRITE) && |
5923 | (file->f_flags & O_TRUNC)) | |
345ddcc8 | 5924 | ftrace_pid_reset(tr); |
756d17ee | 5925 | |
345ddcc8 SRRH |
5926 | ret = seq_open(file, &ftrace_pid_sops); |
5927 | if (ret < 0) { | |
5928 | trace_array_put(tr); | |
5929 | } else { | |
5930 | m = file->private_data; | |
5931 | /* copy tr over to seq ops */ | |
5932 | m->private = tr; | |
5933 | } | |
756d17ee | 5934 | |
5935 | return ret; | |
5936 | } | |
5937 | ||
345ddcc8 SRRH |
5938 | static void ignore_task_cpu(void *data) |
5939 | { | |
5940 | struct trace_array *tr = data; | |
5941 | struct trace_pid_list *pid_list; | |
5942 | ||
5943 | /* | |
5944 | * This function is called by on_each_cpu() while the | |
5945 | * event_mutex is held. | |
5946 | */ | |
5947 | pid_list = rcu_dereference_protected(tr->function_pids, | |
5948 | mutex_is_locked(&ftrace_lock)); | |
5949 | ||
5950 | this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid, | |
5951 | trace_ignore_this_task(pid_list, current)); | |
5952 | } | |
5953 | ||
df4fc315 SR |
5954 | static ssize_t |
5955 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
5956 | size_t cnt, loff_t *ppos) | |
5957 | { | |
345ddcc8 SRRH |
5958 | struct seq_file *m = filp->private_data; |
5959 | struct trace_array *tr = m->private; | |
5960 | struct trace_pid_list *filtered_pids = NULL; | |
5961 | struct trace_pid_list *pid_list; | |
5962 | ssize_t ret; | |
df4fc315 | 5963 | |
345ddcc8 SRRH |
5964 | if (!cnt) |
5965 | return 0; | |
5966 | ||
5967 | mutex_lock(&ftrace_lock); | |
5968 | ||
5969 | filtered_pids = rcu_dereference_protected(tr->function_pids, | |
5970 | lockdep_is_held(&ftrace_lock)); | |
5971 | ||
5972 | ret = trace_pid_write(filtered_pids, &pid_list, ubuf, cnt); | |
5973 | if (ret < 0) | |
5974 | goto out; | |
df4fc315 | 5975 | |
345ddcc8 | 5976 | rcu_assign_pointer(tr->function_pids, pid_list); |
df4fc315 | 5977 | |
345ddcc8 SRRH |
5978 | if (filtered_pids) { |
5979 | synchronize_sched(); | |
5980 | trace_free_pid_list(filtered_pids); | |
5981 | } else if (pid_list) { | |
5982 | /* Register a probe to set whether to ignore the tracing of a task */ | |
5983 | register_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr); | |
5984 | } | |
df4fc315 | 5985 | |
756d17ee | 5986 | /* |
345ddcc8 SRRH |
5987 | * Ignoring of pids is done at task switch. But we have to |
5988 | * check for those tasks that are currently running. | |
5989 | * Always do this in case a pid was appended or removed. | |
756d17ee | 5990 | */ |
345ddcc8 | 5991 | on_each_cpu(ignore_task_cpu, tr, 1); |
756d17ee | 5992 | |
345ddcc8 SRRH |
5993 | ftrace_update_pid_func(); |
5994 | ftrace_startup_all(0); | |
5995 | out: | |
5996 | mutex_unlock(&ftrace_lock); | |
df4fc315 | 5997 | |
345ddcc8 SRRH |
5998 | if (ret > 0) |
5999 | *ppos += ret; | |
df4fc315 | 6000 | |
345ddcc8 | 6001 | return ret; |
756d17ee | 6002 | } |
df4fc315 | 6003 | |
756d17ee | 6004 | static int |
6005 | ftrace_pid_release(struct inode *inode, struct file *file) | |
6006 | { | |
345ddcc8 | 6007 | struct trace_array *tr = inode->i_private; |
df4fc315 | 6008 | |
345ddcc8 SRRH |
6009 | trace_array_put(tr); |
6010 | ||
6011 | return seq_release(inode, file); | |
df4fc315 SR |
6012 | } |
6013 | ||
5e2336a0 | 6014 | static const struct file_operations ftrace_pid_fops = { |
756d17ee | 6015 | .open = ftrace_pid_open, |
6016 | .write = ftrace_pid_write, | |
6017 | .read = seq_read, | |
098c879e | 6018 | .llseek = tracing_lseek, |
756d17ee | 6019 | .release = ftrace_pid_release, |
df4fc315 SR |
6020 | }; |
6021 | ||
345ddcc8 | 6022 | void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
df4fc315 | 6023 | { |
5452af66 | 6024 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
345ddcc8 | 6025 | tr, &ftrace_pid_fops); |
df4fc315 | 6026 | } |
df4fc315 | 6027 | |
501c2375 SRRH |
6028 | void __init ftrace_init_tracefs_toplevel(struct trace_array *tr, |
6029 | struct dentry *d_tracer) | |
6030 | { | |
6031 | /* Only the top level directory has the dyn_tracefs and profile */ | |
6032 | WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); | |
6033 | ||
6034 | ftrace_init_dyn_tracefs(d_tracer); | |
6035 | ftrace_profile_tracefs(d_tracer); | |
6036 | } | |
6037 | ||
a2bb6a3d | 6038 | /** |
81adbdc0 | 6039 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
6040 | * |
6041 | * This function should be used by panic code. It stops ftrace | |
6042 | * but in a not so nice way. If you need to simply kill ftrace | |
6043 | * from a non-atomic section, use ftrace_kill. | |
6044 | */ | |
81adbdc0 | 6045 | void ftrace_kill(void) |
a2bb6a3d SR |
6046 | { |
6047 | ftrace_disabled = 1; | |
6048 | ftrace_enabled = 0; | |
a2bb6a3d SR |
6049 | clear_ftrace_function(); |
6050 | } | |
6051 | ||
e0a413f6 SR |
6052 | /** |
6053 | * Test if ftrace is dead or not. | |
6054 | */ | |
6055 | int ftrace_is_dead(void) | |
6056 | { | |
6057 | return ftrace_disabled; | |
6058 | } | |
6059 | ||
16444a8a | 6060 | /** |
3d083395 SR |
6061 | * register_ftrace_function - register a function for profiling |
6062 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 6063 | * |
3d083395 SR |
6064 | * Register a function to be called by all functions in the |
6065 | * kernel. | |
6066 | * | |
6067 | * Note: @ops->func and all the functions it calls must be labeled | |
6068 | * with "notrace", otherwise it will go into a | |
6069 | * recursive loop. | |
16444a8a | 6070 | */ |
3d083395 | 6071 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 6072 | { |
45a4a237 | 6073 | int ret = -1; |
4eebcc81 | 6074 | |
f04f24fb MH |
6075 | ftrace_ops_init(ops); |
6076 | ||
e6ea44e9 | 6077 | mutex_lock(&ftrace_lock); |
e7d3737e | 6078 | |
8a56d776 | 6079 | ret = ftrace_startup(ops, 0); |
b848914c | 6080 | |
e6ea44e9 | 6081 | mutex_unlock(&ftrace_lock); |
8d240dd8 | 6082 | |
b0fc494f | 6083 | return ret; |
3d083395 | 6084 | } |
cdbe61bf | 6085 | EXPORT_SYMBOL_GPL(register_ftrace_function); |
3d083395 SR |
6086 | |
6087 | /** | |
32632920 | 6088 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
6089 | * @ops - ops structure that holds the function to unregister |
6090 | * | |
6091 | * Unregister a function that was added to be called by ftrace profiling. | |
6092 | */ | |
6093 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
6094 | { | |
6095 | int ret; | |
6096 | ||
e6ea44e9 | 6097 | mutex_lock(&ftrace_lock); |
8a56d776 | 6098 | ret = ftrace_shutdown(ops, 0); |
e6ea44e9 | 6099 | mutex_unlock(&ftrace_lock); |
b0fc494f SR |
6100 | |
6101 | return ret; | |
6102 | } | |
cdbe61bf | 6103 | EXPORT_SYMBOL_GPL(unregister_ftrace_function); |
b0fc494f | 6104 | |
e309b41d | 6105 | int |
b0fc494f | 6106 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
8d65af78 | 6107 | void __user *buffer, size_t *lenp, |
b0fc494f SR |
6108 | loff_t *ppos) |
6109 | { | |
45a4a237 | 6110 | int ret = -ENODEV; |
4eebcc81 | 6111 | |
e6ea44e9 | 6112 | mutex_lock(&ftrace_lock); |
b0fc494f | 6113 | |
45a4a237 SR |
6114 | if (unlikely(ftrace_disabled)) |
6115 | goto out; | |
6116 | ||
6117 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
b0fc494f | 6118 | |
a32c7765 | 6119 | if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) |
b0fc494f SR |
6120 | goto out; |
6121 | ||
a32c7765 | 6122 | last_ftrace_enabled = !!ftrace_enabled; |
b0fc494f SR |
6123 | |
6124 | if (ftrace_enabled) { | |
6125 | ||
b0fc494f | 6126 | /* we are starting ftrace again */ |
5000c418 JK |
6127 | if (ftrace_ops_list != &ftrace_list_end) |
6128 | update_ftrace_function(); | |
b0fc494f | 6129 | |
524a3868 SRRH |
6130 | ftrace_startup_sysctl(); |
6131 | ||
b0fc494f SR |
6132 | } else { |
6133 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
6134 | ftrace_trace_function = ftrace_stub; | |
6135 | ||
6136 | ftrace_shutdown_sysctl(); | |
6137 | } | |
6138 | ||
6139 | out: | |
e6ea44e9 | 6140 | mutex_unlock(&ftrace_lock); |
3d083395 | 6141 | return ret; |
16444a8a | 6142 | } |
f17845e5 | 6143 | |
fb52607a | 6144 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 6145 | |
5f151b24 SRRH |
6146 | static struct ftrace_ops graph_ops = { |
6147 | .func = ftrace_stub, | |
6148 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | | |
6149 | FTRACE_OPS_FL_INITIALIZED | | |
e3eea140 | 6150 | FTRACE_OPS_FL_PID | |
5f151b24 SRRH |
6151 | FTRACE_OPS_FL_STUB, |
6152 | #ifdef FTRACE_GRAPH_TRAMP_ADDR | |
6153 | .trampoline = FTRACE_GRAPH_TRAMP_ADDR, | |
aec0be2d | 6154 | /* trampoline_size is only needed for dynamically allocated tramps */ |
5f151b24 SRRH |
6155 | #endif |
6156 | ASSIGN_OPS_HASH(graph_ops, &global_ops.local_hash) | |
6157 | }; | |
6158 | ||
55577204 SRRH |
6159 | void ftrace_graph_sleep_time_control(bool enable) |
6160 | { | |
6161 | fgraph_sleep_time = enable; | |
6162 | } | |
6163 | ||
6164 | void ftrace_graph_graph_time_control(bool enable) | |
6165 | { | |
6166 | fgraph_graph_time = enable; | |
6167 | } | |
6168 | ||
e49dc19c SR |
6169 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
6170 | { | |
6171 | return 0; | |
6172 | } | |
6173 | ||
287b6e68 FW |
6174 | /* The callbacks that hook a function */ |
6175 | trace_func_graph_ret_t ftrace_graph_return = | |
6176 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 6177 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
23a8e844 | 6178 | static trace_func_graph_ent_t __ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
6179 | |
6180 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
6181 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
6182 | { | |
6183 | int i; | |
6184 | int ret = 0; | |
f201ae23 FW |
6185 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; |
6186 | struct task_struct *g, *t; | |
6187 | ||
6188 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
6189 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
6190 | * sizeof(struct ftrace_ret_stack), | |
6191 | GFP_KERNEL); | |
6192 | if (!ret_stack_list[i]) { | |
6193 | start = 0; | |
6194 | end = i; | |
6195 | ret = -ENOMEM; | |
6196 | goto free; | |
6197 | } | |
6198 | } | |
6199 | ||
6112a300 | 6200 | read_lock(&tasklist_lock); |
f201ae23 FW |
6201 | do_each_thread(g, t) { |
6202 | if (start == end) { | |
6203 | ret = -EAGAIN; | |
6204 | goto unlock; | |
6205 | } | |
6206 | ||
6207 | if (t->ret_stack == NULL) { | |
380c4b14 | 6208 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 | 6209 | atomic_set(&t->trace_overrun, 0); |
26c01624 SR |
6210 | t->curr_ret_stack = -1; |
6211 | /* Make sure the tasks see the -1 first: */ | |
6212 | smp_wmb(); | |
6213 | t->ret_stack = ret_stack_list[start++]; | |
f201ae23 FW |
6214 | } |
6215 | } while_each_thread(g, t); | |
6216 | ||
6217 | unlock: | |
6112a300 | 6218 | read_unlock(&tasklist_lock); |
f201ae23 FW |
6219 | free: |
6220 | for (i = start; i < end; i++) | |
6221 | kfree(ret_stack_list[i]); | |
6222 | return ret; | |
6223 | } | |
6224 | ||
8aef2d28 | 6225 | static void |
c73464b1 | 6226 | ftrace_graph_probe_sched_switch(void *ignore, bool preempt, |
38516ab5 | 6227 | struct task_struct *prev, struct task_struct *next) |
8aef2d28 SR |
6228 | { |
6229 | unsigned long long timestamp; | |
6230 | int index; | |
6231 | ||
be6f164a SR |
6232 | /* |
6233 | * Does the user want to count the time a function was asleep. | |
6234 | * If so, do not update the time stamps. | |
6235 | */ | |
55577204 | 6236 | if (fgraph_sleep_time) |
be6f164a SR |
6237 | return; |
6238 | ||
8aef2d28 SR |
6239 | timestamp = trace_clock_local(); |
6240 | ||
6241 | prev->ftrace_timestamp = timestamp; | |
6242 | ||
6243 | /* only process tasks that we timestamped */ | |
6244 | if (!next->ftrace_timestamp) | |
6245 | return; | |
6246 | ||
6247 | /* | |
6248 | * Update all the counters in next to make up for the | |
6249 | * time next was sleeping. | |
6250 | */ | |
6251 | timestamp -= next->ftrace_timestamp; | |
6252 | ||
6253 | for (index = next->curr_ret_stack; index >= 0; index--) | |
6254 | next->ret_stack[index].calltime += timestamp; | |
6255 | } | |
6256 | ||
f201ae23 | 6257 | /* Allocate a return stack for each task */ |
fb52607a | 6258 | static int start_graph_tracing(void) |
f201ae23 FW |
6259 | { |
6260 | struct ftrace_ret_stack **ret_stack_list; | |
5b058bcd | 6261 | int ret, cpu; |
f201ae23 FW |
6262 | |
6263 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
6264 | sizeof(struct ftrace_ret_stack *), | |
6265 | GFP_KERNEL); | |
6266 | ||
6267 | if (!ret_stack_list) | |
6268 | return -ENOMEM; | |
6269 | ||
5b058bcd | 6270 | /* The cpu_boot init_task->ret_stack will never be freed */ |
179c498a SR |
6271 | for_each_online_cpu(cpu) { |
6272 | if (!idle_task(cpu)->ret_stack) | |
868baf07 | 6273 | ftrace_graph_init_idle_task(idle_task(cpu), cpu); |
179c498a | 6274 | } |
5b058bcd | 6275 | |
f201ae23 FW |
6276 | do { |
6277 | ret = alloc_retstack_tasklist(ret_stack_list); | |
6278 | } while (ret == -EAGAIN); | |
6279 | ||
8aef2d28 | 6280 | if (!ret) { |
38516ab5 | 6281 | ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
8aef2d28 SR |
6282 | if (ret) |
6283 | pr_info("ftrace_graph: Couldn't activate tracepoint" | |
6284 | " probe to kernel_sched_switch\n"); | |
6285 | } | |
6286 | ||
f201ae23 FW |
6287 | kfree(ret_stack_list); |
6288 | return ret; | |
6289 | } | |
6290 | ||
4a2b8dda FW |
6291 | /* |
6292 | * Hibernation protection. | |
6293 | * The state of the current task is too much unstable during | |
6294 | * suspend/restore to disk. We want to protect against that. | |
6295 | */ | |
6296 | static int | |
6297 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, | |
6298 | void *unused) | |
6299 | { | |
6300 | switch (state) { | |
6301 | case PM_HIBERNATION_PREPARE: | |
6302 | pause_graph_tracing(); | |
6303 | break; | |
6304 | ||
6305 | case PM_POST_HIBERNATION: | |
6306 | unpause_graph_tracing(); | |
6307 | break; | |
6308 | } | |
6309 | return NOTIFY_DONE; | |
6310 | } | |
6311 | ||
23a8e844 SRRH |
6312 | static int ftrace_graph_entry_test(struct ftrace_graph_ent *trace) |
6313 | { | |
6314 | if (!ftrace_ops_test(&global_ops, trace->func, NULL)) | |
6315 | return 0; | |
6316 | return __ftrace_graph_entry(trace); | |
6317 | } | |
6318 | ||
6319 | /* | |
6320 | * The function graph tracer should only trace the functions defined | |
6321 | * by set_ftrace_filter and set_ftrace_notrace. If another function | |
6322 | * tracer ops is registered, the graph tracer requires testing the | |
6323 | * function against the global ops, and not just trace any function | |
6324 | * that any ftrace_ops registered. | |
6325 | */ | |
6326 | static void update_function_graph_func(void) | |
6327 | { | |
5f151b24 SRRH |
6328 | struct ftrace_ops *op; |
6329 | bool do_test = false; | |
6330 | ||
6331 | /* | |
6332 | * The graph and global ops share the same set of functions | |
6333 | * to test. If any other ops is on the list, then | |
6334 | * the graph tracing needs to test if its the function | |
6335 | * it should call. | |
6336 | */ | |
6337 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
6338 | if (op != &global_ops && op != &graph_ops && | |
6339 | op != &ftrace_list_end) { | |
6340 | do_test = true; | |
6341 | /* in double loop, break out with goto */ | |
6342 | goto out; | |
6343 | } | |
6344 | } while_for_each_ftrace_op(op); | |
6345 | out: | |
6346 | if (do_test) | |
23a8e844 | 6347 | ftrace_graph_entry = ftrace_graph_entry_test; |
5f151b24 SRRH |
6348 | else |
6349 | ftrace_graph_entry = __ftrace_graph_entry; | |
23a8e844 SRRH |
6350 | } |
6351 | ||
8275f69f MK |
6352 | static struct notifier_block ftrace_suspend_notifier = { |
6353 | .notifier_call = ftrace_suspend_notifier_call, | |
6354 | }; | |
6355 | ||
287b6e68 FW |
6356 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
6357 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 6358 | { |
e7d3737e FW |
6359 | int ret = 0; |
6360 | ||
e6ea44e9 | 6361 | mutex_lock(&ftrace_lock); |
e7d3737e | 6362 | |
05ce5818 | 6363 | /* we currently allow only one tracer registered at a time */ |
597af815 | 6364 | if (ftrace_graph_active) { |
05ce5818 SR |
6365 | ret = -EBUSY; |
6366 | goto out; | |
6367 | } | |
6368 | ||
4a2b8dda FW |
6369 | register_pm_notifier(&ftrace_suspend_notifier); |
6370 | ||
597af815 | 6371 | ftrace_graph_active++; |
fb52607a | 6372 | ret = start_graph_tracing(); |
f201ae23 | 6373 | if (ret) { |
597af815 | 6374 | ftrace_graph_active--; |
f201ae23 FW |
6375 | goto out; |
6376 | } | |
e53a6319 | 6377 | |
287b6e68 | 6378 | ftrace_graph_return = retfunc; |
23a8e844 SRRH |
6379 | |
6380 | /* | |
6381 | * Update the indirect function to the entryfunc, and the | |
6382 | * function that gets called to the entry_test first. Then | |
6383 | * call the update fgraph entry function to determine if | |
6384 | * the entryfunc should be called directly or not. | |
6385 | */ | |
6386 | __ftrace_graph_entry = entryfunc; | |
6387 | ftrace_graph_entry = ftrace_graph_entry_test; | |
6388 | update_function_graph_func(); | |
e53a6319 | 6389 | |
5f151b24 | 6390 | ret = ftrace_startup(&graph_ops, FTRACE_START_FUNC_RET); |
e7d3737e | 6391 | out: |
e6ea44e9 | 6392 | mutex_unlock(&ftrace_lock); |
e7d3737e | 6393 | return ret; |
15e6cb36 FW |
6394 | } |
6395 | ||
fb52607a | 6396 | void unregister_ftrace_graph(void) |
15e6cb36 | 6397 | { |
e6ea44e9 | 6398 | mutex_lock(&ftrace_lock); |
e7d3737e | 6399 | |
597af815 | 6400 | if (unlikely(!ftrace_graph_active)) |
2aad1b76 SR |
6401 | goto out; |
6402 | ||
597af815 | 6403 | ftrace_graph_active--; |
287b6e68 | 6404 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; |
e49dc19c | 6405 | ftrace_graph_entry = ftrace_graph_entry_stub; |
23a8e844 | 6406 | __ftrace_graph_entry = ftrace_graph_entry_stub; |
5f151b24 | 6407 | ftrace_shutdown(&graph_ops, FTRACE_STOP_FUNC_RET); |
4a2b8dda | 6408 | unregister_pm_notifier(&ftrace_suspend_notifier); |
38516ab5 | 6409 | unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
e7d3737e | 6410 | |
f3bea491 SRRH |
6411 | #ifdef CONFIG_DYNAMIC_FTRACE |
6412 | /* | |
6413 | * Function graph does not allocate the trampoline, but | |
6414 | * other global_ops do. We need to reset the ALLOC_TRAMP flag | |
6415 | * if one was used. | |
6416 | */ | |
6417 | global_ops.trampoline = save_global_trampoline; | |
6418 | if (save_global_flags & FTRACE_OPS_FL_ALLOC_TRAMP) | |
6419 | global_ops.flags |= FTRACE_OPS_FL_ALLOC_TRAMP; | |
6420 | #endif | |
6421 | ||
2aad1b76 | 6422 | out: |
e6ea44e9 | 6423 | mutex_unlock(&ftrace_lock); |
15e6cb36 | 6424 | } |
f201ae23 | 6425 | |
868baf07 SR |
6426 | static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack); |
6427 | ||
6428 | static void | |
6429 | graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack) | |
6430 | { | |
6431 | atomic_set(&t->tracing_graph_pause, 0); | |
6432 | atomic_set(&t->trace_overrun, 0); | |
6433 | t->ftrace_timestamp = 0; | |
25985edc | 6434 | /* make curr_ret_stack visible before we add the ret_stack */ |
868baf07 SR |
6435 | smp_wmb(); |
6436 | t->ret_stack = ret_stack; | |
6437 | } | |
6438 | ||
6439 | /* | |
6440 | * Allocate a return stack for the idle task. May be the first | |
6441 | * time through, or it may be done by CPU hotplug online. | |
6442 | */ | |
6443 | void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) | |
6444 | { | |
6445 | t->curr_ret_stack = -1; | |
6446 | /* | |
6447 | * The idle task has no parent, it either has its own | |
6448 | * stack or no stack at all. | |
6449 | */ | |
6450 | if (t->ret_stack) | |
6451 | WARN_ON(t->ret_stack != per_cpu(idle_ret_stack, cpu)); | |
6452 | ||
6453 | if (ftrace_graph_active) { | |
6454 | struct ftrace_ret_stack *ret_stack; | |
6455 | ||
6456 | ret_stack = per_cpu(idle_ret_stack, cpu); | |
6457 | if (!ret_stack) { | |
6458 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
6459 | * sizeof(struct ftrace_ret_stack), | |
6460 | GFP_KERNEL); | |
6461 | if (!ret_stack) | |
6462 | return; | |
6463 | per_cpu(idle_ret_stack, cpu) = ret_stack; | |
6464 | } | |
6465 | graph_init_task(t, ret_stack); | |
6466 | } | |
6467 | } | |
6468 | ||
f201ae23 | 6469 | /* Allocate a return stack for newly created task */ |
fb52607a | 6470 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 6471 | { |
84047e36 SR |
6472 | /* Make sure we do not use the parent ret_stack */ |
6473 | t->ret_stack = NULL; | |
ea14eb71 | 6474 | t->curr_ret_stack = -1; |
84047e36 | 6475 | |
597af815 | 6476 | if (ftrace_graph_active) { |
82310a32 SR |
6477 | struct ftrace_ret_stack *ret_stack; |
6478 | ||
6479 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
f201ae23 FW |
6480 | * sizeof(struct ftrace_ret_stack), |
6481 | GFP_KERNEL); | |
82310a32 | 6482 | if (!ret_stack) |
f201ae23 | 6483 | return; |
868baf07 | 6484 | graph_init_task(t, ret_stack); |
84047e36 | 6485 | } |
f201ae23 FW |
6486 | } |
6487 | ||
fb52607a | 6488 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 6489 | { |
eae849ca FW |
6490 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
6491 | ||
f201ae23 | 6492 | t->ret_stack = NULL; |
eae849ca FW |
6493 | /* NULL must become visible to IRQs before we free it: */ |
6494 | barrier(); | |
6495 | ||
6496 | kfree(ret_stack); | |
f201ae23 | 6497 | } |
15e6cb36 | 6498 | #endif |