]>
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 | |
13 | * Copyright (C) 2004 William Lee Irwin III | |
14 | */ | |
15 | ||
3d083395 SR |
16 | #include <linux/stop_machine.h> |
17 | #include <linux/clocksource.h> | |
18 | #include <linux/kallsyms.h> | |
5072c59f SR |
19 | #include <linux/seq_file.h> |
20 | #include <linux/debugfs.h> | |
3d083395 | 21 | #include <linux/hardirq.h> |
2d8b820b | 22 | #include <linux/kthread.h> |
5072c59f | 23 | #include <linux/uaccess.h> |
f22f9a89 | 24 | #include <linux/kprobes.h> |
2d8b820b | 25 | #include <linux/ftrace.h> |
b0fc494f | 26 | #include <linux/sysctl.h> |
5072c59f | 27 | #include <linux/ctype.h> |
3d083395 SR |
28 | #include <linux/list.h> |
29 | ||
395a59d0 AS |
30 | #include <asm/ftrace.h> |
31 | ||
3d083395 | 32 | #include "trace.h" |
16444a8a | 33 | |
6912896e SR |
34 | #define FTRACE_WARN_ON(cond) \ |
35 | do { \ | |
36 | if (WARN_ON(cond)) \ | |
37 | ftrace_kill(); \ | |
38 | } while (0) | |
39 | ||
40 | #define FTRACE_WARN_ON_ONCE(cond) \ | |
41 | do { \ | |
42 | if (WARN_ON_ONCE(cond)) \ | |
43 | ftrace_kill(); \ | |
44 | } while (0) | |
45 | ||
4eebcc81 SR |
46 | /* ftrace_enabled is a method to turn ftrace on or off */ |
47 | int ftrace_enabled __read_mostly; | |
d61f82d0 | 48 | static int last_ftrace_enabled; |
b0fc494f | 49 | |
0ef8cde5 | 50 | /* set when tracing only a pid */ |
978f3a45 | 51 | struct pid *ftrace_pid_trace; |
e32d8956 | 52 | static struct pid * const ftrace_swapper_pid = (struct pid *)1; |
df4fc315 | 53 | |
60a7ecf4 SR |
54 | /* Quick disabling of function tracer. */ |
55 | int function_trace_stop; | |
56 | ||
4eebcc81 SR |
57 | /* |
58 | * ftrace_disabled is set when an anomaly is discovered. | |
59 | * ftrace_disabled is much stronger than ftrace_enabled. | |
60 | */ | |
61 | static int ftrace_disabled __read_mostly; | |
62 | ||
3d083395 | 63 | static DEFINE_SPINLOCK(ftrace_lock); |
b0fc494f | 64 | static DEFINE_MUTEX(ftrace_sysctl_lock); |
df4fc315 | 65 | static DEFINE_MUTEX(ftrace_start_lock); |
b0fc494f | 66 | |
16444a8a ACM |
67 | static struct ftrace_ops ftrace_list_end __read_mostly = |
68 | { | |
69 | .func = ftrace_stub, | |
70 | }; | |
71 | ||
72 | static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end; | |
73 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; | |
60a7ecf4 | 74 | ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub; |
df4fc315 | 75 | ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub; |
16444a8a | 76 | |
f2252935 | 77 | static void ftrace_list_func(unsigned long ip, unsigned long parent_ip) |
16444a8a ACM |
78 | { |
79 | struct ftrace_ops *op = ftrace_list; | |
80 | ||
81 | /* in case someone actually ports this to alpha! */ | |
82 | read_barrier_depends(); | |
83 | ||
84 | while (op != &ftrace_list_end) { | |
85 | /* silly alpha */ | |
86 | read_barrier_depends(); | |
87 | op->func(ip, parent_ip); | |
88 | op = op->next; | |
89 | }; | |
90 | } | |
91 | ||
df4fc315 SR |
92 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip) |
93 | { | |
0ef8cde5 | 94 | if (!test_tsk_trace_trace(current)) |
df4fc315 SR |
95 | return; |
96 | ||
97 | ftrace_pid_function(ip, parent_ip); | |
98 | } | |
99 | ||
100 | static void set_ftrace_pid_function(ftrace_func_t func) | |
101 | { | |
102 | /* do not set ftrace_pid_function to itself! */ | |
103 | if (func != ftrace_pid_func) | |
104 | ftrace_pid_function = func; | |
105 | } | |
106 | ||
16444a8a | 107 | /** |
3d083395 | 108 | * clear_ftrace_function - reset the ftrace function |
16444a8a | 109 | * |
3d083395 SR |
110 | * This NULLs the ftrace function and in essence stops |
111 | * tracing. There may be lag | |
16444a8a | 112 | */ |
3d083395 | 113 | void clear_ftrace_function(void) |
16444a8a | 114 | { |
3d083395 | 115 | ftrace_trace_function = ftrace_stub; |
60a7ecf4 | 116 | __ftrace_trace_function = ftrace_stub; |
df4fc315 | 117 | ftrace_pid_function = ftrace_stub; |
3d083395 SR |
118 | } |
119 | ||
60a7ecf4 SR |
120 | #ifndef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
121 | /* | |
122 | * For those archs that do not test ftrace_trace_stop in their | |
123 | * mcount call site, we need to do it from C. | |
124 | */ | |
125 | static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip) | |
126 | { | |
127 | if (function_trace_stop) | |
128 | return; | |
129 | ||
130 | __ftrace_trace_function(ip, parent_ip); | |
131 | } | |
132 | #endif | |
133 | ||
e309b41d | 134 | static int __register_ftrace_function(struct ftrace_ops *ops) |
3d083395 | 135 | { |
99ecdc43 | 136 | /* should not be called from interrupt context */ |
3d083395 | 137 | spin_lock(&ftrace_lock); |
16444a8a | 138 | |
16444a8a ACM |
139 | ops->next = ftrace_list; |
140 | /* | |
141 | * We are entering ops into the ftrace_list but another | |
142 | * CPU might be walking that list. We need to make sure | |
143 | * the ops->next pointer is valid before another CPU sees | |
144 | * the ops pointer included into the ftrace_list. | |
145 | */ | |
146 | smp_wmb(); | |
147 | ftrace_list = ops; | |
3d083395 | 148 | |
b0fc494f | 149 | if (ftrace_enabled) { |
df4fc315 SR |
150 | ftrace_func_t func; |
151 | ||
152 | if (ops->next == &ftrace_list_end) | |
153 | func = ops->func; | |
154 | else | |
155 | func = ftrace_list_func; | |
156 | ||
978f3a45 | 157 | if (ftrace_pid_trace) { |
df4fc315 SR |
158 | set_ftrace_pid_function(func); |
159 | func = ftrace_pid_func; | |
160 | } | |
161 | ||
b0fc494f SR |
162 | /* |
163 | * For one func, simply call it directly. | |
164 | * For more than one func, call the chain. | |
165 | */ | |
60a7ecf4 | 166 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
df4fc315 | 167 | ftrace_trace_function = func; |
60a7ecf4 | 168 | #else |
df4fc315 | 169 | __ftrace_trace_function = func; |
60a7ecf4 SR |
170 | ftrace_trace_function = ftrace_test_stop_func; |
171 | #endif | |
b0fc494f | 172 | } |
3d083395 SR |
173 | |
174 | spin_unlock(&ftrace_lock); | |
16444a8a ACM |
175 | |
176 | return 0; | |
177 | } | |
178 | ||
e309b41d | 179 | static int __unregister_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 180 | { |
16444a8a ACM |
181 | struct ftrace_ops **p; |
182 | int ret = 0; | |
183 | ||
99ecdc43 | 184 | /* should not be called from interrupt context */ |
3d083395 | 185 | spin_lock(&ftrace_lock); |
16444a8a ACM |
186 | |
187 | /* | |
3d083395 SR |
188 | * If we are removing the last function, then simply point |
189 | * to the ftrace_stub. | |
16444a8a ACM |
190 | */ |
191 | if (ftrace_list == ops && ops->next == &ftrace_list_end) { | |
192 | ftrace_trace_function = ftrace_stub; | |
193 | ftrace_list = &ftrace_list_end; | |
194 | goto out; | |
195 | } | |
196 | ||
197 | for (p = &ftrace_list; *p != &ftrace_list_end; p = &(*p)->next) | |
198 | if (*p == ops) | |
199 | break; | |
200 | ||
201 | if (*p != ops) { | |
202 | ret = -1; | |
203 | goto out; | |
204 | } | |
205 | ||
206 | *p = (*p)->next; | |
207 | ||
b0fc494f SR |
208 | if (ftrace_enabled) { |
209 | /* If we only have one func left, then call that directly */ | |
df4fc315 SR |
210 | if (ftrace_list->next == &ftrace_list_end) { |
211 | ftrace_func_t func = ftrace_list->func; | |
212 | ||
978f3a45 | 213 | if (ftrace_pid_trace) { |
df4fc315 SR |
214 | set_ftrace_pid_function(func); |
215 | func = ftrace_pid_func; | |
216 | } | |
217 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST | |
218 | ftrace_trace_function = func; | |
219 | #else | |
220 | __ftrace_trace_function = func; | |
221 | #endif | |
222 | } | |
b0fc494f | 223 | } |
16444a8a ACM |
224 | |
225 | out: | |
3d083395 SR |
226 | spin_unlock(&ftrace_lock); |
227 | ||
228 | return ret; | |
229 | } | |
230 | ||
df4fc315 SR |
231 | static void ftrace_update_pid_func(void) |
232 | { | |
233 | ftrace_func_t func; | |
234 | ||
235 | /* should not be called from interrupt context */ | |
236 | spin_lock(&ftrace_lock); | |
237 | ||
238 | if (ftrace_trace_function == ftrace_stub) | |
239 | goto out; | |
240 | ||
241 | func = ftrace_trace_function; | |
242 | ||
978f3a45 | 243 | if (ftrace_pid_trace) { |
df4fc315 SR |
244 | set_ftrace_pid_function(func); |
245 | func = ftrace_pid_func; | |
246 | } else { | |
66eafebc LW |
247 | if (func == ftrace_pid_func) |
248 | func = ftrace_pid_function; | |
df4fc315 SR |
249 | } |
250 | ||
251 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST | |
252 | ftrace_trace_function = func; | |
253 | #else | |
254 | __ftrace_trace_function = func; | |
255 | #endif | |
256 | ||
257 | out: | |
258 | spin_unlock(&ftrace_lock); | |
259 | } | |
260 | ||
3d083395 | 261 | #ifdef CONFIG_DYNAMIC_FTRACE |
99ecdc43 | 262 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD |
cb7be3b2 | 263 | # error Dynamic ftrace depends on MCOUNT_RECORD |
99ecdc43 SR |
264 | #endif |
265 | ||
71c67d58 SN |
266 | /* |
267 | * Since MCOUNT_ADDR may point to mcount itself, we do not want | |
268 | * to get it confused by reading a reference in the code as we | |
269 | * are parsing on objcopy output of text. Use a variable for | |
270 | * it instead. | |
271 | */ | |
272 | static unsigned long mcount_addr = MCOUNT_ADDR; | |
273 | ||
d61f82d0 SR |
274 | enum { |
275 | FTRACE_ENABLE_CALLS = (1 << 0), | |
276 | FTRACE_DISABLE_CALLS = (1 << 1), | |
277 | FTRACE_UPDATE_TRACE_FUNC = (1 << 2), | |
278 | FTRACE_ENABLE_MCOUNT = (1 << 3), | |
279 | FTRACE_DISABLE_MCOUNT = (1 << 4), | |
5a45cfe1 SR |
280 | FTRACE_START_FUNC_RET = (1 << 5), |
281 | FTRACE_STOP_FUNC_RET = (1 << 6), | |
d61f82d0 SR |
282 | }; |
283 | ||
5072c59f SR |
284 | static int ftrace_filtered; |
285 | ||
08f5ac90 | 286 | static LIST_HEAD(ftrace_new_addrs); |
3d083395 | 287 | |
41c52c0d | 288 | static DEFINE_MUTEX(ftrace_regex_lock); |
3d083395 | 289 | |
3c1720f0 SR |
290 | struct ftrace_page { |
291 | struct ftrace_page *next; | |
aa5e5cea | 292 | unsigned long index; |
3c1720f0 | 293 | struct dyn_ftrace records[]; |
aa5e5cea | 294 | }; |
3c1720f0 SR |
295 | |
296 | #define ENTRIES_PER_PAGE \ | |
297 | ((PAGE_SIZE - sizeof(struct ftrace_page)) / sizeof(struct dyn_ftrace)) | |
298 | ||
299 | /* estimate from running different kernels */ | |
300 | #define NR_TO_INIT 10000 | |
301 | ||
302 | static struct ftrace_page *ftrace_pages_start; | |
303 | static struct ftrace_page *ftrace_pages; | |
304 | ||
37ad5084 SR |
305 | static struct dyn_ftrace *ftrace_free_records; |
306 | ||
ecea656d AS |
307 | |
308 | #ifdef CONFIG_KPROBES | |
f17845e5 IM |
309 | |
310 | static int frozen_record_count; | |
311 | ||
ecea656d AS |
312 | static inline void freeze_record(struct dyn_ftrace *rec) |
313 | { | |
314 | if (!(rec->flags & FTRACE_FL_FROZEN)) { | |
315 | rec->flags |= FTRACE_FL_FROZEN; | |
316 | frozen_record_count++; | |
317 | } | |
318 | } | |
319 | ||
320 | static inline void unfreeze_record(struct dyn_ftrace *rec) | |
321 | { | |
322 | if (rec->flags & FTRACE_FL_FROZEN) { | |
323 | rec->flags &= ~FTRACE_FL_FROZEN; | |
324 | frozen_record_count--; | |
325 | } | |
326 | } | |
327 | ||
328 | static inline int record_frozen(struct dyn_ftrace *rec) | |
329 | { | |
330 | return rec->flags & FTRACE_FL_FROZEN; | |
331 | } | |
332 | #else | |
333 | # define freeze_record(rec) ({ 0; }) | |
334 | # define unfreeze_record(rec) ({ 0; }) | |
335 | # define record_frozen(rec) ({ 0; }) | |
336 | #endif /* CONFIG_KPROBES */ | |
337 | ||
e309b41d | 338 | static void ftrace_free_rec(struct dyn_ftrace *rec) |
37ad5084 | 339 | { |
37ad5084 SR |
340 | rec->ip = (unsigned long)ftrace_free_records; |
341 | ftrace_free_records = rec; | |
342 | rec->flags |= FTRACE_FL_FREE; | |
343 | } | |
344 | ||
fed1939c SR |
345 | void ftrace_release(void *start, unsigned long size) |
346 | { | |
347 | struct dyn_ftrace *rec; | |
348 | struct ftrace_page *pg; | |
349 | unsigned long s = (unsigned long)start; | |
350 | unsigned long e = s + size; | |
351 | int i; | |
352 | ||
00fd61ae | 353 | if (ftrace_disabled || !start) |
fed1939c SR |
354 | return; |
355 | ||
99ecdc43 | 356 | /* should not be called from interrupt context */ |
fed1939c SR |
357 | spin_lock(&ftrace_lock); |
358 | ||
359 | for (pg = ftrace_pages_start; pg; pg = pg->next) { | |
360 | for (i = 0; i < pg->index; i++) { | |
361 | rec = &pg->records[i]; | |
362 | ||
363 | if ((rec->ip >= s) && (rec->ip < e)) | |
364 | ftrace_free_rec(rec); | |
365 | } | |
366 | } | |
367 | spin_unlock(&ftrace_lock); | |
fed1939c SR |
368 | } |
369 | ||
e309b41d | 370 | static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip) |
3c1720f0 | 371 | { |
37ad5084 SR |
372 | struct dyn_ftrace *rec; |
373 | ||
374 | /* First check for freed records */ | |
375 | if (ftrace_free_records) { | |
376 | rec = ftrace_free_records; | |
377 | ||
37ad5084 | 378 | if (unlikely(!(rec->flags & FTRACE_FL_FREE))) { |
6912896e | 379 | FTRACE_WARN_ON_ONCE(1); |
37ad5084 SR |
380 | ftrace_free_records = NULL; |
381 | return NULL; | |
382 | } | |
383 | ||
384 | ftrace_free_records = (void *)rec->ip; | |
385 | memset(rec, 0, sizeof(*rec)); | |
386 | return rec; | |
387 | } | |
388 | ||
3c1720f0 | 389 | if (ftrace_pages->index == ENTRIES_PER_PAGE) { |
08f5ac90 SR |
390 | if (!ftrace_pages->next) { |
391 | /* allocate another page */ | |
392 | ftrace_pages->next = | |
393 | (void *)get_zeroed_page(GFP_KERNEL); | |
394 | if (!ftrace_pages->next) | |
395 | return NULL; | |
396 | } | |
3c1720f0 SR |
397 | ftrace_pages = ftrace_pages->next; |
398 | } | |
399 | ||
400 | return &ftrace_pages->records[ftrace_pages->index++]; | |
401 | } | |
402 | ||
08f5ac90 | 403 | static struct dyn_ftrace * |
d61f82d0 | 404 | ftrace_record_ip(unsigned long ip) |
3d083395 | 405 | { |
08f5ac90 | 406 | struct dyn_ftrace *rec; |
3d083395 | 407 | |
f3c7ac40 | 408 | if (ftrace_disabled) |
08f5ac90 | 409 | return NULL; |
3d083395 | 410 | |
08f5ac90 SR |
411 | rec = ftrace_alloc_dyn_node(ip); |
412 | if (!rec) | |
413 | return NULL; | |
3d083395 | 414 | |
08f5ac90 | 415 | rec->ip = ip; |
3d083395 | 416 | |
08f5ac90 | 417 | list_add(&rec->list, &ftrace_new_addrs); |
3d083395 | 418 | |
08f5ac90 | 419 | return rec; |
3d083395 SR |
420 | } |
421 | ||
b17e8a37 SR |
422 | static void print_ip_ins(const char *fmt, unsigned char *p) |
423 | { | |
424 | int i; | |
425 | ||
426 | printk(KERN_CONT "%s", fmt); | |
427 | ||
428 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
429 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
430 | } | |
431 | ||
31e88909 | 432 | static void ftrace_bug(int failed, unsigned long ip) |
b17e8a37 SR |
433 | { |
434 | switch (failed) { | |
435 | case -EFAULT: | |
436 | FTRACE_WARN_ON_ONCE(1); | |
437 | pr_info("ftrace faulted on modifying "); | |
438 | print_ip_sym(ip); | |
439 | break; | |
440 | case -EINVAL: | |
441 | FTRACE_WARN_ON_ONCE(1); | |
442 | pr_info("ftrace failed to modify "); | |
443 | print_ip_sym(ip); | |
b17e8a37 | 444 | print_ip_ins(" actual: ", (unsigned char *)ip); |
b17e8a37 SR |
445 | printk(KERN_CONT "\n"); |
446 | break; | |
447 | case -EPERM: | |
448 | FTRACE_WARN_ON_ONCE(1); | |
449 | pr_info("ftrace faulted on writing "); | |
450 | print_ip_sym(ip); | |
451 | break; | |
452 | default: | |
453 | FTRACE_WARN_ON_ONCE(1); | |
454 | pr_info("ftrace faulted on unknown error "); | |
455 | print_ip_sym(ip); | |
456 | } | |
457 | } | |
458 | ||
3c1720f0 | 459 | |
0eb96701 | 460 | static int |
31e88909 | 461 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) |
5072c59f | 462 | { |
41c52c0d | 463 | unsigned long ip, fl; |
e7d3737e FW |
464 | unsigned long ftrace_addr; |
465 | ||
e7d3737e | 466 | ftrace_addr = (unsigned long)ftrace_caller; |
5072c59f SR |
467 | |
468 | ip = rec->ip; | |
469 | ||
982c350b SR |
470 | /* |
471 | * If this record is not to be traced and | |
472 | * it is not enabled then do nothing. | |
473 | * | |
474 | * If this record is not to be traced and | |
475 | * it is enabled then disabled it. | |
476 | * | |
477 | */ | |
478 | if (rec->flags & FTRACE_FL_NOTRACE) { | |
479 | if (rec->flags & FTRACE_FL_ENABLED) | |
480 | rec->flags &= ~FTRACE_FL_ENABLED; | |
481 | else | |
482 | return 0; | |
483 | ||
484 | } else if (ftrace_filtered && enable) { | |
5072c59f | 485 | /* |
982c350b | 486 | * Filtering is on: |
5072c59f | 487 | */ |
a4500b84 | 488 | |
982c350b | 489 | fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED); |
5072c59f | 490 | |
982c350b SR |
491 | /* Record is filtered and enabled, do nothing */ |
492 | if (fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED)) | |
0eb96701 | 493 | return 0; |
5072c59f | 494 | |
982c350b SR |
495 | /* Record is not filtered and is not enabled do nothing */ |
496 | if (!fl) | |
497 | return 0; | |
498 | ||
499 | /* Record is not filtered but enabled, disable it */ | |
500 | if (fl == FTRACE_FL_ENABLED) | |
5072c59f | 501 | rec->flags &= ~FTRACE_FL_ENABLED; |
982c350b SR |
502 | else |
503 | /* Otherwise record is filtered but not enabled, enable it */ | |
5072c59f | 504 | rec->flags |= FTRACE_FL_ENABLED; |
5072c59f | 505 | } else { |
982c350b | 506 | /* Disable or not filtered */ |
5072c59f | 507 | |
41c52c0d | 508 | if (enable) { |
982c350b | 509 | /* if record is enabled, do nothing */ |
5072c59f | 510 | if (rec->flags & FTRACE_FL_ENABLED) |
0eb96701 | 511 | return 0; |
982c350b | 512 | |
5072c59f | 513 | rec->flags |= FTRACE_FL_ENABLED; |
982c350b | 514 | |
5072c59f | 515 | } else { |
982c350b SR |
516 | |
517 | /* if record is not enabled do nothing */ | |
5072c59f | 518 | if (!(rec->flags & FTRACE_FL_ENABLED)) |
0eb96701 | 519 | return 0; |
982c350b | 520 | |
5072c59f SR |
521 | rec->flags &= ~FTRACE_FL_ENABLED; |
522 | } | |
523 | } | |
524 | ||
982c350b | 525 | if (rec->flags & FTRACE_FL_ENABLED) |
e7d3737e | 526 | return ftrace_make_call(rec, ftrace_addr); |
31e88909 | 527 | else |
e7d3737e | 528 | return ftrace_make_nop(NULL, rec, ftrace_addr); |
5072c59f SR |
529 | } |
530 | ||
e309b41d | 531 | static void ftrace_replace_code(int enable) |
3c1720f0 | 532 | { |
0eb96701 | 533 | int i, failed; |
3c1720f0 SR |
534 | struct dyn_ftrace *rec; |
535 | struct ftrace_page *pg; | |
3c1720f0 | 536 | |
3c1720f0 SR |
537 | for (pg = ftrace_pages_start; pg; pg = pg->next) { |
538 | for (i = 0; i < pg->index; i++) { | |
539 | rec = &pg->records[i]; | |
540 | ||
918c1154 SR |
541 | /* |
542 | * Skip over free records and records that have | |
543 | * failed. | |
544 | */ | |
545 | if (rec->flags & FTRACE_FL_FREE || | |
546 | rec->flags & FTRACE_FL_FAILED) | |
3c1720f0 SR |
547 | continue; |
548 | ||
f22f9a89 | 549 | /* ignore updates to this record's mcount site */ |
98a05ed4 AS |
550 | if (get_kprobe((void *)rec->ip)) { |
551 | freeze_record(rec); | |
f22f9a89 | 552 | continue; |
98a05ed4 AS |
553 | } else { |
554 | unfreeze_record(rec); | |
555 | } | |
f22f9a89 | 556 | |
31e88909 | 557 | failed = __ftrace_replace_code(rec, enable); |
0eb96701 AS |
558 | if (failed && (rec->flags & FTRACE_FL_CONVERTED)) { |
559 | rec->flags |= FTRACE_FL_FAILED; | |
560 | if ((system_state == SYSTEM_BOOTING) || | |
34078a5e | 561 | !core_kernel_text(rec->ip)) { |
0eb96701 | 562 | ftrace_free_rec(rec); |
b17e8a37 | 563 | } else |
31e88909 | 564 | ftrace_bug(failed, rec->ip); |
0eb96701 | 565 | } |
3c1720f0 SR |
566 | } |
567 | } | |
568 | } | |
569 | ||
492a7ea5 | 570 | static int |
31e88909 | 571 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 SR |
572 | { |
573 | unsigned long ip; | |
593eb8a2 | 574 | int ret; |
3c1720f0 SR |
575 | |
576 | ip = rec->ip; | |
577 | ||
31e88909 | 578 | ret = ftrace_make_nop(mod, rec, mcount_addr); |
593eb8a2 | 579 | if (ret) { |
31e88909 | 580 | ftrace_bug(ret, ip); |
3c1720f0 | 581 | rec->flags |= FTRACE_FL_FAILED; |
492a7ea5 | 582 | return 0; |
37ad5084 | 583 | } |
492a7ea5 | 584 | return 1; |
3c1720f0 SR |
585 | } |
586 | ||
e309b41d | 587 | static int __ftrace_modify_code(void *data) |
3d083395 | 588 | { |
d61f82d0 SR |
589 | int *command = data; |
590 | ||
a3583244 | 591 | if (*command & FTRACE_ENABLE_CALLS) |
d61f82d0 | 592 | ftrace_replace_code(1); |
a3583244 | 593 | else if (*command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
594 | ftrace_replace_code(0); |
595 | ||
596 | if (*command & FTRACE_UPDATE_TRACE_FUNC) | |
597 | ftrace_update_ftrace_func(ftrace_trace_function); | |
598 | ||
5a45cfe1 SR |
599 | if (*command & FTRACE_START_FUNC_RET) |
600 | ftrace_enable_ftrace_graph_caller(); | |
601 | else if (*command & FTRACE_STOP_FUNC_RET) | |
602 | ftrace_disable_ftrace_graph_caller(); | |
603 | ||
d61f82d0 | 604 | return 0; |
3d083395 SR |
605 | } |
606 | ||
e309b41d | 607 | static void ftrace_run_update_code(int command) |
3d083395 | 608 | { |
784e2d76 | 609 | stop_machine(__ftrace_modify_code, &command, NULL); |
3d083395 SR |
610 | } |
611 | ||
d61f82d0 | 612 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 613 | static int ftrace_start_up; |
df4fc315 SR |
614 | |
615 | static void ftrace_startup_enable(int command) | |
616 | { | |
617 | if (saved_ftrace_func != ftrace_trace_function) { | |
618 | saved_ftrace_func = ftrace_trace_function; | |
619 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
620 | } | |
621 | ||
622 | if (!command || !ftrace_enabled) | |
623 | return; | |
624 | ||
625 | ftrace_run_update_code(command); | |
626 | } | |
d61f82d0 | 627 | |
5a45cfe1 | 628 | static void ftrace_startup(int command) |
3d083395 | 629 | { |
4eebcc81 SR |
630 | if (unlikely(ftrace_disabled)) |
631 | return; | |
632 | ||
cb7be3b2 | 633 | mutex_lock(&ftrace_start_lock); |
60a7ecf4 | 634 | ftrace_start_up++; |
982c350b | 635 | command |= FTRACE_ENABLE_CALLS; |
d61f82d0 | 636 | |
df4fc315 | 637 | ftrace_startup_enable(command); |
3d083395 | 638 | |
cb7be3b2 | 639 | mutex_unlock(&ftrace_start_lock); |
3d083395 SR |
640 | } |
641 | ||
5a45cfe1 | 642 | static void ftrace_shutdown(int command) |
3d083395 | 643 | { |
4eebcc81 SR |
644 | if (unlikely(ftrace_disabled)) |
645 | return; | |
646 | ||
cb7be3b2 | 647 | mutex_lock(&ftrace_start_lock); |
60a7ecf4 SR |
648 | ftrace_start_up--; |
649 | if (!ftrace_start_up) | |
d61f82d0 | 650 | command |= FTRACE_DISABLE_CALLS; |
3d083395 | 651 | |
d61f82d0 SR |
652 | if (saved_ftrace_func != ftrace_trace_function) { |
653 | saved_ftrace_func = ftrace_trace_function; | |
654 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
655 | } | |
3d083395 | 656 | |
d61f82d0 SR |
657 | if (!command || !ftrace_enabled) |
658 | goto out; | |
659 | ||
660 | ftrace_run_update_code(command); | |
3d083395 | 661 | out: |
cb7be3b2 | 662 | mutex_unlock(&ftrace_start_lock); |
3d083395 SR |
663 | } |
664 | ||
e309b41d | 665 | static void ftrace_startup_sysctl(void) |
b0fc494f | 666 | { |
d61f82d0 SR |
667 | int command = FTRACE_ENABLE_MCOUNT; |
668 | ||
4eebcc81 SR |
669 | if (unlikely(ftrace_disabled)) |
670 | return; | |
671 | ||
cb7be3b2 | 672 | mutex_lock(&ftrace_start_lock); |
d61f82d0 SR |
673 | /* Force update next time */ |
674 | saved_ftrace_func = NULL; | |
60a7ecf4 SR |
675 | /* ftrace_start_up is true if we want ftrace running */ |
676 | if (ftrace_start_up) | |
d61f82d0 SR |
677 | command |= FTRACE_ENABLE_CALLS; |
678 | ||
679 | ftrace_run_update_code(command); | |
cb7be3b2 | 680 | mutex_unlock(&ftrace_start_lock); |
b0fc494f SR |
681 | } |
682 | ||
e309b41d | 683 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 684 | { |
d61f82d0 SR |
685 | int command = FTRACE_DISABLE_MCOUNT; |
686 | ||
4eebcc81 SR |
687 | if (unlikely(ftrace_disabled)) |
688 | return; | |
689 | ||
cb7be3b2 | 690 | mutex_lock(&ftrace_start_lock); |
60a7ecf4 SR |
691 | /* ftrace_start_up is true if ftrace is running */ |
692 | if (ftrace_start_up) | |
d61f82d0 SR |
693 | command |= FTRACE_DISABLE_CALLS; |
694 | ||
695 | ftrace_run_update_code(command); | |
cb7be3b2 | 696 | mutex_unlock(&ftrace_start_lock); |
b0fc494f SR |
697 | } |
698 | ||
3d083395 SR |
699 | static cycle_t ftrace_update_time; |
700 | static unsigned long ftrace_update_cnt; | |
701 | unsigned long ftrace_update_tot_cnt; | |
702 | ||
31e88909 | 703 | static int ftrace_update_code(struct module *mod) |
3d083395 | 704 | { |
08f5ac90 | 705 | struct dyn_ftrace *p, *t; |
f22f9a89 | 706 | cycle_t start, stop; |
3d083395 | 707 | |
750ed1a4 | 708 | start = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
709 | ftrace_update_cnt = 0; |
710 | ||
08f5ac90 | 711 | list_for_each_entry_safe(p, t, &ftrace_new_addrs, list) { |
3d083395 | 712 | |
08f5ac90 SR |
713 | /* If something went wrong, bail without enabling anything */ |
714 | if (unlikely(ftrace_disabled)) | |
715 | return -1; | |
f22f9a89 | 716 | |
08f5ac90 | 717 | list_del_init(&p->list); |
f22f9a89 | 718 | |
08f5ac90 | 719 | /* convert record (i.e, patch mcount-call with NOP) */ |
31e88909 | 720 | if (ftrace_code_disable(mod, p)) { |
08f5ac90 SR |
721 | p->flags |= FTRACE_FL_CONVERTED; |
722 | ftrace_update_cnt++; | |
723 | } else | |
724 | ftrace_free_rec(p); | |
3d083395 SR |
725 | } |
726 | ||
750ed1a4 | 727 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
728 | ftrace_update_time = stop - start; |
729 | ftrace_update_tot_cnt += ftrace_update_cnt; | |
730 | ||
16444a8a ACM |
731 | return 0; |
732 | } | |
733 | ||
68bf21aa | 734 | static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) |
3c1720f0 SR |
735 | { |
736 | struct ftrace_page *pg; | |
737 | int cnt; | |
738 | int i; | |
3c1720f0 SR |
739 | |
740 | /* allocate a few pages */ | |
741 | ftrace_pages_start = (void *)get_zeroed_page(GFP_KERNEL); | |
742 | if (!ftrace_pages_start) | |
743 | return -1; | |
744 | ||
745 | /* | |
746 | * Allocate a few more pages. | |
747 | * | |
748 | * TODO: have some parser search vmlinux before | |
749 | * final linking to find all calls to ftrace. | |
750 | * Then we can: | |
751 | * a) know how many pages to allocate. | |
752 | * and/or | |
753 | * b) set up the table then. | |
754 | * | |
755 | * The dynamic code is still necessary for | |
756 | * modules. | |
757 | */ | |
758 | ||
759 | pg = ftrace_pages = ftrace_pages_start; | |
760 | ||
68bf21aa | 761 | cnt = num_to_init / ENTRIES_PER_PAGE; |
08f5ac90 | 762 | pr_info("ftrace: allocating %ld entries in %d pages\n", |
5821e1b7 | 763 | num_to_init, cnt + 1); |
3c1720f0 SR |
764 | |
765 | for (i = 0; i < cnt; i++) { | |
766 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); | |
767 | ||
768 | /* If we fail, we'll try later anyway */ | |
769 | if (!pg->next) | |
770 | break; | |
771 | ||
772 | pg = pg->next; | |
773 | } | |
774 | ||
775 | return 0; | |
776 | } | |
777 | ||
5072c59f SR |
778 | enum { |
779 | FTRACE_ITER_FILTER = (1 << 0), | |
780 | FTRACE_ITER_CONT = (1 << 1), | |
41c52c0d | 781 | FTRACE_ITER_NOTRACE = (1 << 2), |
eb9a7bf0 | 782 | FTRACE_ITER_FAILURES = (1 << 3), |
5072c59f SR |
783 | }; |
784 | ||
785 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ | |
786 | ||
787 | struct ftrace_iterator { | |
5072c59f SR |
788 | struct ftrace_page *pg; |
789 | unsigned idx; | |
790 | unsigned flags; | |
791 | unsigned char buffer[FTRACE_BUFF_MAX+1]; | |
792 | unsigned buffer_idx; | |
793 | unsigned filtered; | |
794 | }; | |
795 | ||
e309b41d | 796 | static void * |
5072c59f SR |
797 | t_next(struct seq_file *m, void *v, loff_t *pos) |
798 | { | |
799 | struct ftrace_iterator *iter = m->private; | |
800 | struct dyn_ftrace *rec = NULL; | |
801 | ||
802 | (*pos)++; | |
803 | ||
99ecdc43 SR |
804 | /* should not be called from interrupt context */ |
805 | spin_lock(&ftrace_lock); | |
5072c59f SR |
806 | retry: |
807 | if (iter->idx >= iter->pg->index) { | |
808 | if (iter->pg->next) { | |
809 | iter->pg = iter->pg->next; | |
810 | iter->idx = 0; | |
811 | goto retry; | |
50cdaf08 LW |
812 | } else { |
813 | iter->idx = -1; | |
5072c59f SR |
814 | } |
815 | } else { | |
816 | rec = &iter->pg->records[iter->idx++]; | |
a9fdda33 SR |
817 | if ((rec->flags & FTRACE_FL_FREE) || |
818 | ||
819 | (!(iter->flags & FTRACE_ITER_FAILURES) && | |
eb9a7bf0 AS |
820 | (rec->flags & FTRACE_FL_FAILED)) || |
821 | ||
822 | ((iter->flags & FTRACE_ITER_FAILURES) && | |
a9fdda33 | 823 | !(rec->flags & FTRACE_FL_FAILED)) || |
eb9a7bf0 | 824 | |
0183fb1c SR |
825 | ((iter->flags & FTRACE_ITER_FILTER) && |
826 | !(rec->flags & FTRACE_FL_FILTER)) || | |
827 | ||
41c52c0d SR |
828 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
829 | !(rec->flags & FTRACE_FL_NOTRACE))) { | |
5072c59f SR |
830 | rec = NULL; |
831 | goto retry; | |
832 | } | |
833 | } | |
99ecdc43 | 834 | spin_unlock(&ftrace_lock); |
5072c59f | 835 | |
5072c59f SR |
836 | return rec; |
837 | } | |
838 | ||
839 | static void *t_start(struct seq_file *m, loff_t *pos) | |
840 | { | |
841 | struct ftrace_iterator *iter = m->private; | |
842 | void *p = NULL; | |
5072c59f | 843 | |
50cdaf08 LW |
844 | if (*pos > 0) { |
845 | if (iter->idx < 0) | |
846 | return p; | |
847 | (*pos)--; | |
848 | iter->idx--; | |
849 | } | |
5821e1b7 | 850 | |
50cdaf08 | 851 | p = t_next(m, p, pos); |
5072c59f SR |
852 | |
853 | return p; | |
854 | } | |
855 | ||
856 | static void t_stop(struct seq_file *m, void *p) | |
857 | { | |
858 | } | |
859 | ||
860 | static int t_show(struct seq_file *m, void *v) | |
861 | { | |
862 | struct dyn_ftrace *rec = v; | |
863 | char str[KSYM_SYMBOL_LEN]; | |
864 | ||
865 | if (!rec) | |
866 | return 0; | |
867 | ||
868 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
869 | ||
50cdaf08 | 870 | seq_printf(m, "%s\n", str); |
5072c59f SR |
871 | |
872 | return 0; | |
873 | } | |
874 | ||
875 | static struct seq_operations show_ftrace_seq_ops = { | |
876 | .start = t_start, | |
877 | .next = t_next, | |
878 | .stop = t_stop, | |
879 | .show = t_show, | |
880 | }; | |
881 | ||
e309b41d | 882 | static int |
5072c59f SR |
883 | ftrace_avail_open(struct inode *inode, struct file *file) |
884 | { | |
885 | struct ftrace_iterator *iter; | |
886 | int ret; | |
887 | ||
4eebcc81 SR |
888 | if (unlikely(ftrace_disabled)) |
889 | return -ENODEV; | |
890 | ||
5072c59f SR |
891 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
892 | if (!iter) | |
893 | return -ENOMEM; | |
894 | ||
895 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
896 | |
897 | ret = seq_open(file, &show_ftrace_seq_ops); | |
898 | if (!ret) { | |
899 | struct seq_file *m = file->private_data; | |
4bf39a94 | 900 | |
5072c59f | 901 | m->private = iter; |
4bf39a94 | 902 | } else { |
5072c59f | 903 | kfree(iter); |
4bf39a94 | 904 | } |
5072c59f SR |
905 | |
906 | return ret; | |
907 | } | |
908 | ||
909 | int ftrace_avail_release(struct inode *inode, struct file *file) | |
910 | { | |
911 | struct seq_file *m = (struct seq_file *)file->private_data; | |
912 | struct ftrace_iterator *iter = m->private; | |
913 | ||
914 | seq_release(inode, file); | |
915 | kfree(iter); | |
4bf39a94 | 916 | |
5072c59f SR |
917 | return 0; |
918 | } | |
919 | ||
eb9a7bf0 AS |
920 | static int |
921 | ftrace_failures_open(struct inode *inode, struct file *file) | |
922 | { | |
923 | int ret; | |
924 | struct seq_file *m; | |
925 | struct ftrace_iterator *iter; | |
926 | ||
927 | ret = ftrace_avail_open(inode, file); | |
928 | if (!ret) { | |
929 | m = (struct seq_file *)file->private_data; | |
930 | iter = (struct ftrace_iterator *)m->private; | |
931 | iter->flags = FTRACE_ITER_FAILURES; | |
932 | } | |
933 | ||
934 | return ret; | |
935 | } | |
936 | ||
937 | ||
41c52c0d | 938 | static void ftrace_filter_reset(int enable) |
5072c59f SR |
939 | { |
940 | struct ftrace_page *pg; | |
941 | struct dyn_ftrace *rec; | |
41c52c0d | 942 | unsigned long type = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
5072c59f SR |
943 | unsigned i; |
944 | ||
99ecdc43 SR |
945 | /* should not be called from interrupt context */ |
946 | spin_lock(&ftrace_lock); | |
41c52c0d SR |
947 | if (enable) |
948 | ftrace_filtered = 0; | |
5072c59f SR |
949 | pg = ftrace_pages_start; |
950 | while (pg) { | |
951 | for (i = 0; i < pg->index; i++) { | |
952 | rec = &pg->records[i]; | |
953 | if (rec->flags & FTRACE_FL_FAILED) | |
954 | continue; | |
41c52c0d | 955 | rec->flags &= ~type; |
5072c59f SR |
956 | } |
957 | pg = pg->next; | |
958 | } | |
99ecdc43 | 959 | spin_unlock(&ftrace_lock); |
5072c59f SR |
960 | } |
961 | ||
e309b41d | 962 | static int |
41c52c0d | 963 | ftrace_regex_open(struct inode *inode, struct file *file, int enable) |
5072c59f SR |
964 | { |
965 | struct ftrace_iterator *iter; | |
966 | int ret = 0; | |
967 | ||
4eebcc81 SR |
968 | if (unlikely(ftrace_disabled)) |
969 | return -ENODEV; | |
970 | ||
5072c59f SR |
971 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
972 | if (!iter) | |
973 | return -ENOMEM; | |
974 | ||
41c52c0d | 975 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
976 | if ((file->f_mode & FMODE_WRITE) && |
977 | !(file->f_flags & O_APPEND)) | |
41c52c0d | 978 | ftrace_filter_reset(enable); |
5072c59f SR |
979 | |
980 | if (file->f_mode & FMODE_READ) { | |
981 | iter->pg = ftrace_pages_start; | |
41c52c0d SR |
982 | iter->flags = enable ? FTRACE_ITER_FILTER : |
983 | FTRACE_ITER_NOTRACE; | |
5072c59f SR |
984 | |
985 | ret = seq_open(file, &show_ftrace_seq_ops); | |
986 | if (!ret) { | |
987 | struct seq_file *m = file->private_data; | |
988 | m->private = iter; | |
989 | } else | |
990 | kfree(iter); | |
991 | } else | |
992 | file->private_data = iter; | |
41c52c0d | 993 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
994 | |
995 | return ret; | |
996 | } | |
997 | ||
41c52c0d SR |
998 | static int |
999 | ftrace_filter_open(struct inode *inode, struct file *file) | |
1000 | { | |
1001 | return ftrace_regex_open(inode, file, 1); | |
1002 | } | |
1003 | ||
1004 | static int | |
1005 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
1006 | { | |
1007 | return ftrace_regex_open(inode, file, 0); | |
1008 | } | |
1009 | ||
e309b41d | 1010 | static ssize_t |
41c52c0d | 1011 | ftrace_regex_read(struct file *file, char __user *ubuf, |
5072c59f SR |
1012 | size_t cnt, loff_t *ppos) |
1013 | { | |
1014 | if (file->f_mode & FMODE_READ) | |
1015 | return seq_read(file, ubuf, cnt, ppos); | |
1016 | else | |
1017 | return -EPERM; | |
1018 | } | |
1019 | ||
e309b41d | 1020 | static loff_t |
41c52c0d | 1021 | ftrace_regex_lseek(struct file *file, loff_t offset, int origin) |
5072c59f SR |
1022 | { |
1023 | loff_t ret; | |
1024 | ||
1025 | if (file->f_mode & FMODE_READ) | |
1026 | ret = seq_lseek(file, offset, origin); | |
1027 | else | |
1028 | file->f_pos = ret = 1; | |
1029 | ||
1030 | return ret; | |
1031 | } | |
1032 | ||
1033 | enum { | |
1034 | MATCH_FULL, | |
1035 | MATCH_FRONT_ONLY, | |
1036 | MATCH_MIDDLE_ONLY, | |
1037 | MATCH_END_ONLY, | |
1038 | }; | |
1039 | ||
e309b41d | 1040 | static void |
41c52c0d | 1041 | ftrace_match(unsigned char *buff, int len, int enable) |
5072c59f SR |
1042 | { |
1043 | char str[KSYM_SYMBOL_LEN]; | |
1044 | char *search = NULL; | |
1045 | struct ftrace_page *pg; | |
1046 | struct dyn_ftrace *rec; | |
1047 | int type = MATCH_FULL; | |
41c52c0d | 1048 | unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
5072c59f SR |
1049 | unsigned i, match = 0, search_len = 0; |
1050 | ||
1051 | for (i = 0; i < len; i++) { | |
1052 | if (buff[i] == '*') { | |
1053 | if (!i) { | |
1054 | search = buff + i + 1; | |
1055 | type = MATCH_END_ONLY; | |
1056 | search_len = len - (i + 1); | |
1057 | } else { | |
1058 | if (type == MATCH_END_ONLY) { | |
1059 | type = MATCH_MIDDLE_ONLY; | |
1060 | } else { | |
1061 | match = i; | |
1062 | type = MATCH_FRONT_ONLY; | |
1063 | } | |
1064 | buff[i] = 0; | |
1065 | break; | |
1066 | } | |
1067 | } | |
1068 | } | |
1069 | ||
99ecdc43 SR |
1070 | /* should not be called from interrupt context */ |
1071 | spin_lock(&ftrace_lock); | |
41c52c0d SR |
1072 | if (enable) |
1073 | ftrace_filtered = 1; | |
5072c59f SR |
1074 | pg = ftrace_pages_start; |
1075 | while (pg) { | |
1076 | for (i = 0; i < pg->index; i++) { | |
1077 | int matched = 0; | |
1078 | char *ptr; | |
1079 | ||
1080 | rec = &pg->records[i]; | |
1081 | if (rec->flags & FTRACE_FL_FAILED) | |
1082 | continue; | |
1083 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
1084 | switch (type) { | |
1085 | case MATCH_FULL: | |
1086 | if (strcmp(str, buff) == 0) | |
1087 | matched = 1; | |
1088 | break; | |
1089 | case MATCH_FRONT_ONLY: | |
1090 | if (memcmp(str, buff, match) == 0) | |
1091 | matched = 1; | |
1092 | break; | |
1093 | case MATCH_MIDDLE_ONLY: | |
1094 | if (strstr(str, search)) | |
1095 | matched = 1; | |
1096 | break; | |
1097 | case MATCH_END_ONLY: | |
1098 | ptr = strstr(str, search); | |
1099 | if (ptr && (ptr[search_len] == 0)) | |
1100 | matched = 1; | |
1101 | break; | |
1102 | } | |
1103 | if (matched) | |
41c52c0d | 1104 | rec->flags |= flag; |
5072c59f SR |
1105 | } |
1106 | pg = pg->next; | |
1107 | } | |
99ecdc43 | 1108 | spin_unlock(&ftrace_lock); |
5072c59f SR |
1109 | } |
1110 | ||
e309b41d | 1111 | static ssize_t |
41c52c0d SR |
1112 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
1113 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
1114 | { |
1115 | struct ftrace_iterator *iter; | |
1116 | char ch; | |
1117 | size_t read = 0; | |
1118 | ssize_t ret; | |
1119 | ||
1120 | if (!cnt || cnt < 0) | |
1121 | return 0; | |
1122 | ||
41c52c0d | 1123 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
1124 | |
1125 | if (file->f_mode & FMODE_READ) { | |
1126 | struct seq_file *m = file->private_data; | |
1127 | iter = m->private; | |
1128 | } else | |
1129 | iter = file->private_data; | |
1130 | ||
1131 | if (!*ppos) { | |
1132 | iter->flags &= ~FTRACE_ITER_CONT; | |
1133 | iter->buffer_idx = 0; | |
1134 | } | |
1135 | ||
1136 | ret = get_user(ch, ubuf++); | |
1137 | if (ret) | |
1138 | goto out; | |
1139 | read++; | |
1140 | cnt--; | |
1141 | ||
1142 | if (!(iter->flags & ~FTRACE_ITER_CONT)) { | |
1143 | /* skip white space */ | |
1144 | while (cnt && isspace(ch)) { | |
1145 | ret = get_user(ch, ubuf++); | |
1146 | if (ret) | |
1147 | goto out; | |
1148 | read++; | |
1149 | cnt--; | |
1150 | } | |
1151 | ||
5072c59f SR |
1152 | if (isspace(ch)) { |
1153 | file->f_pos += read; | |
1154 | ret = read; | |
1155 | goto out; | |
1156 | } | |
1157 | ||
1158 | iter->buffer_idx = 0; | |
1159 | } | |
1160 | ||
1161 | while (cnt && !isspace(ch)) { | |
1162 | if (iter->buffer_idx < FTRACE_BUFF_MAX) | |
1163 | iter->buffer[iter->buffer_idx++] = ch; | |
1164 | else { | |
1165 | ret = -EINVAL; | |
1166 | goto out; | |
1167 | } | |
1168 | ret = get_user(ch, ubuf++); | |
1169 | if (ret) | |
1170 | goto out; | |
1171 | read++; | |
1172 | cnt--; | |
1173 | } | |
1174 | ||
1175 | if (isspace(ch)) { | |
1176 | iter->filtered++; | |
1177 | iter->buffer[iter->buffer_idx] = 0; | |
41c52c0d | 1178 | ftrace_match(iter->buffer, iter->buffer_idx, enable); |
5072c59f SR |
1179 | iter->buffer_idx = 0; |
1180 | } else | |
1181 | iter->flags |= FTRACE_ITER_CONT; | |
1182 | ||
1183 | ||
1184 | file->f_pos += read; | |
1185 | ||
1186 | ret = read; | |
1187 | out: | |
41c52c0d | 1188 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
1189 | |
1190 | return ret; | |
1191 | } | |
1192 | ||
41c52c0d SR |
1193 | static ssize_t |
1194 | ftrace_filter_write(struct file *file, const char __user *ubuf, | |
1195 | size_t cnt, loff_t *ppos) | |
1196 | { | |
1197 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
1198 | } | |
1199 | ||
1200 | static ssize_t | |
1201 | ftrace_notrace_write(struct file *file, const char __user *ubuf, | |
1202 | size_t cnt, loff_t *ppos) | |
1203 | { | |
1204 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
1205 | } | |
1206 | ||
1207 | static void | |
1208 | ftrace_set_regex(unsigned char *buf, int len, int reset, int enable) | |
1209 | { | |
1210 | if (unlikely(ftrace_disabled)) | |
1211 | return; | |
1212 | ||
1213 | mutex_lock(&ftrace_regex_lock); | |
1214 | if (reset) | |
1215 | ftrace_filter_reset(enable); | |
1216 | if (buf) | |
1217 | ftrace_match(buf, len, enable); | |
1218 | mutex_unlock(&ftrace_regex_lock); | |
1219 | } | |
1220 | ||
77a2b37d SR |
1221 | /** |
1222 | * ftrace_set_filter - set a function to filter on in ftrace | |
1223 | * @buf - the string that holds the function filter text. | |
1224 | * @len - the length of the string. | |
1225 | * @reset - non zero to reset all filters before applying this filter. | |
1226 | * | |
1227 | * Filters denote which functions should be enabled when tracing is enabled. | |
1228 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
1229 | */ | |
e309b41d | 1230 | void ftrace_set_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 1231 | { |
41c52c0d SR |
1232 | ftrace_set_regex(buf, len, reset, 1); |
1233 | } | |
4eebcc81 | 1234 | |
41c52c0d SR |
1235 | /** |
1236 | * ftrace_set_notrace - set a function to not trace in ftrace | |
1237 | * @buf - the string that holds the function notrace text. | |
1238 | * @len - the length of the string. | |
1239 | * @reset - non zero to reset all filters before applying this filter. | |
1240 | * | |
1241 | * Notrace Filters denote which functions should not be enabled when tracing | |
1242 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
1243 | * for tracing. | |
1244 | */ | |
1245 | void ftrace_set_notrace(unsigned char *buf, int len, int reset) | |
1246 | { | |
1247 | ftrace_set_regex(buf, len, reset, 0); | |
77a2b37d SR |
1248 | } |
1249 | ||
e309b41d | 1250 | static int |
41c52c0d | 1251 | ftrace_regex_release(struct inode *inode, struct file *file, int enable) |
5072c59f SR |
1252 | { |
1253 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1254 | struct ftrace_iterator *iter; | |
1255 | ||
41c52c0d | 1256 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
1257 | if (file->f_mode & FMODE_READ) { |
1258 | iter = m->private; | |
1259 | ||
1260 | seq_release(inode, file); | |
1261 | } else | |
1262 | iter = file->private_data; | |
1263 | ||
1264 | if (iter->buffer_idx) { | |
1265 | iter->filtered++; | |
1266 | iter->buffer[iter->buffer_idx] = 0; | |
41c52c0d | 1267 | ftrace_match(iter->buffer, iter->buffer_idx, enable); |
5072c59f SR |
1268 | } |
1269 | ||
1270 | mutex_lock(&ftrace_sysctl_lock); | |
cb7be3b2 | 1271 | mutex_lock(&ftrace_start_lock); |
ee02a2e5 | 1272 | if (ftrace_start_up && ftrace_enabled) |
5072c59f | 1273 | ftrace_run_update_code(FTRACE_ENABLE_CALLS); |
cb7be3b2 | 1274 | mutex_unlock(&ftrace_start_lock); |
5072c59f SR |
1275 | mutex_unlock(&ftrace_sysctl_lock); |
1276 | ||
1277 | kfree(iter); | |
41c52c0d | 1278 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
1279 | return 0; |
1280 | } | |
1281 | ||
41c52c0d SR |
1282 | static int |
1283 | ftrace_filter_release(struct inode *inode, struct file *file) | |
1284 | { | |
1285 | return ftrace_regex_release(inode, file, 1); | |
1286 | } | |
1287 | ||
1288 | static int | |
1289 | ftrace_notrace_release(struct inode *inode, struct file *file) | |
1290 | { | |
1291 | return ftrace_regex_release(inode, file, 0); | |
1292 | } | |
1293 | ||
5072c59f SR |
1294 | static struct file_operations ftrace_avail_fops = { |
1295 | .open = ftrace_avail_open, | |
1296 | .read = seq_read, | |
1297 | .llseek = seq_lseek, | |
1298 | .release = ftrace_avail_release, | |
1299 | }; | |
1300 | ||
eb9a7bf0 AS |
1301 | static struct file_operations ftrace_failures_fops = { |
1302 | .open = ftrace_failures_open, | |
1303 | .read = seq_read, | |
1304 | .llseek = seq_lseek, | |
1305 | .release = ftrace_avail_release, | |
1306 | }; | |
1307 | ||
5072c59f SR |
1308 | static struct file_operations ftrace_filter_fops = { |
1309 | .open = ftrace_filter_open, | |
41c52c0d | 1310 | .read = ftrace_regex_read, |
5072c59f | 1311 | .write = ftrace_filter_write, |
41c52c0d | 1312 | .llseek = ftrace_regex_lseek, |
5072c59f SR |
1313 | .release = ftrace_filter_release, |
1314 | }; | |
1315 | ||
41c52c0d SR |
1316 | static struct file_operations ftrace_notrace_fops = { |
1317 | .open = ftrace_notrace_open, | |
1318 | .read = ftrace_regex_read, | |
1319 | .write = ftrace_notrace_write, | |
1320 | .llseek = ftrace_regex_lseek, | |
1321 | .release = ftrace_notrace_release, | |
1322 | }; | |
1323 | ||
ea4e2bc4 SR |
1324 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
1325 | ||
1326 | static DEFINE_MUTEX(graph_lock); | |
1327 | ||
1328 | int ftrace_graph_count; | |
1329 | unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; | |
1330 | ||
1331 | static void * | |
1332 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
1333 | { | |
1334 | unsigned long *array = m->private; | |
1335 | int index = *pos; | |
1336 | ||
1337 | (*pos)++; | |
1338 | ||
1339 | if (index >= ftrace_graph_count) | |
1340 | return NULL; | |
1341 | ||
1342 | return &array[index]; | |
1343 | } | |
1344 | ||
1345 | static void *g_start(struct seq_file *m, loff_t *pos) | |
1346 | { | |
1347 | void *p = NULL; | |
1348 | ||
1349 | mutex_lock(&graph_lock); | |
1350 | ||
1351 | p = g_next(m, p, pos); | |
1352 | ||
1353 | return p; | |
1354 | } | |
1355 | ||
1356 | static void g_stop(struct seq_file *m, void *p) | |
1357 | { | |
1358 | mutex_unlock(&graph_lock); | |
1359 | } | |
1360 | ||
1361 | static int g_show(struct seq_file *m, void *v) | |
1362 | { | |
1363 | unsigned long *ptr = v; | |
1364 | char str[KSYM_SYMBOL_LEN]; | |
1365 | ||
1366 | if (!ptr) | |
1367 | return 0; | |
1368 | ||
1369 | kallsyms_lookup(*ptr, NULL, NULL, NULL, str); | |
1370 | ||
1371 | seq_printf(m, "%s\n", str); | |
1372 | ||
1373 | return 0; | |
1374 | } | |
1375 | ||
1376 | static struct seq_operations ftrace_graph_seq_ops = { | |
1377 | .start = g_start, | |
1378 | .next = g_next, | |
1379 | .stop = g_stop, | |
1380 | .show = g_show, | |
1381 | }; | |
1382 | ||
1383 | static int | |
1384 | ftrace_graph_open(struct inode *inode, struct file *file) | |
1385 | { | |
1386 | int ret = 0; | |
1387 | ||
1388 | if (unlikely(ftrace_disabled)) | |
1389 | return -ENODEV; | |
1390 | ||
1391 | mutex_lock(&graph_lock); | |
1392 | if ((file->f_mode & FMODE_WRITE) && | |
1393 | !(file->f_flags & O_APPEND)) { | |
1394 | ftrace_graph_count = 0; | |
1395 | memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); | |
1396 | } | |
1397 | ||
1398 | if (file->f_mode & FMODE_READ) { | |
1399 | ret = seq_open(file, &ftrace_graph_seq_ops); | |
1400 | if (!ret) { | |
1401 | struct seq_file *m = file->private_data; | |
1402 | m->private = ftrace_graph_funcs; | |
1403 | } | |
1404 | } else | |
1405 | file->private_data = ftrace_graph_funcs; | |
1406 | mutex_unlock(&graph_lock); | |
1407 | ||
1408 | return ret; | |
1409 | } | |
1410 | ||
1411 | static ssize_t | |
1412 | ftrace_graph_read(struct file *file, char __user *ubuf, | |
1413 | size_t cnt, loff_t *ppos) | |
1414 | { | |
1415 | if (file->f_mode & FMODE_READ) | |
1416 | return seq_read(file, ubuf, cnt, ppos); | |
1417 | else | |
1418 | return -EPERM; | |
1419 | } | |
1420 | ||
1421 | static int | |
1422 | ftrace_set_func(unsigned long *array, int idx, char *buffer) | |
1423 | { | |
1424 | char str[KSYM_SYMBOL_LEN]; | |
1425 | struct dyn_ftrace *rec; | |
1426 | struct ftrace_page *pg; | |
1427 | int found = 0; | |
faec2ec5 | 1428 | int i, j; |
ea4e2bc4 SR |
1429 | |
1430 | if (ftrace_disabled) | |
1431 | return -ENODEV; | |
1432 | ||
1433 | /* should not be called from interrupt context */ | |
1434 | spin_lock(&ftrace_lock); | |
1435 | ||
1436 | for (pg = ftrace_pages_start; pg; pg = pg->next) { | |
1437 | for (i = 0; i < pg->index; i++) { | |
1438 | rec = &pg->records[i]; | |
1439 | ||
1440 | if (rec->flags & (FTRACE_FL_FAILED | FTRACE_FL_FREE)) | |
1441 | continue; | |
1442 | ||
1443 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
1444 | if (strcmp(str, buffer) == 0) { | |
1445 | found = 1; | |
faec2ec5 LW |
1446 | for (j = 0; j < idx; j++) |
1447 | if (array[j] == rec->ip) { | |
1448 | found = 0; | |
1449 | break; | |
1450 | } | |
1451 | if (found) | |
1452 | array[idx] = rec->ip; | |
ea4e2bc4 SR |
1453 | break; |
1454 | } | |
1455 | } | |
1456 | } | |
1457 | spin_unlock(&ftrace_lock); | |
1458 | ||
1459 | return found ? 0 : -EINVAL; | |
1460 | } | |
1461 | ||
1462 | static ssize_t | |
1463 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
1464 | size_t cnt, loff_t *ppos) | |
1465 | { | |
1466 | unsigned char buffer[FTRACE_BUFF_MAX+1]; | |
1467 | unsigned long *array; | |
1468 | size_t read = 0; | |
1469 | ssize_t ret; | |
1470 | int index = 0; | |
1471 | char ch; | |
1472 | ||
1473 | if (!cnt || cnt < 0) | |
1474 | return 0; | |
1475 | ||
1476 | mutex_lock(&graph_lock); | |
1477 | ||
1478 | if (ftrace_graph_count >= FTRACE_GRAPH_MAX_FUNCS) { | |
1479 | ret = -EBUSY; | |
1480 | goto out; | |
1481 | } | |
1482 | ||
1483 | if (file->f_mode & FMODE_READ) { | |
1484 | struct seq_file *m = file->private_data; | |
1485 | array = m->private; | |
1486 | } else | |
1487 | array = file->private_data; | |
1488 | ||
1489 | ret = get_user(ch, ubuf++); | |
1490 | if (ret) | |
1491 | goto out; | |
1492 | read++; | |
1493 | cnt--; | |
1494 | ||
1495 | /* skip white space */ | |
1496 | while (cnt && isspace(ch)) { | |
1497 | ret = get_user(ch, ubuf++); | |
1498 | if (ret) | |
1499 | goto out; | |
1500 | read++; | |
1501 | cnt--; | |
1502 | } | |
1503 | ||
1504 | if (isspace(ch)) { | |
1505 | *ppos += read; | |
1506 | ret = read; | |
1507 | goto out; | |
1508 | } | |
1509 | ||
1510 | while (cnt && !isspace(ch)) { | |
1511 | if (index < FTRACE_BUFF_MAX) | |
1512 | buffer[index++] = ch; | |
1513 | else { | |
1514 | ret = -EINVAL; | |
1515 | goto out; | |
1516 | } | |
1517 | ret = get_user(ch, ubuf++); | |
1518 | if (ret) | |
1519 | goto out; | |
1520 | read++; | |
1521 | cnt--; | |
1522 | } | |
1523 | buffer[index] = 0; | |
1524 | ||
1525 | /* we allow only one at a time */ | |
1526 | ret = ftrace_set_func(array, ftrace_graph_count, buffer); | |
1527 | if (ret) | |
1528 | goto out; | |
1529 | ||
1530 | ftrace_graph_count++; | |
1531 | ||
1532 | file->f_pos += read; | |
1533 | ||
1534 | ret = read; | |
1535 | out: | |
1536 | mutex_unlock(&graph_lock); | |
1537 | ||
1538 | return ret; | |
1539 | } | |
1540 | ||
1541 | static const struct file_operations ftrace_graph_fops = { | |
1542 | .open = ftrace_graph_open, | |
1543 | .read = ftrace_graph_read, | |
1544 | .write = ftrace_graph_write, | |
1545 | }; | |
1546 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
1547 | ||
df4fc315 | 1548 | static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) |
5072c59f | 1549 | { |
5072c59f SR |
1550 | struct dentry *entry; |
1551 | ||
5072c59f SR |
1552 | entry = debugfs_create_file("available_filter_functions", 0444, |
1553 | d_tracer, NULL, &ftrace_avail_fops); | |
1554 | if (!entry) | |
1555 | pr_warning("Could not create debugfs " | |
1556 | "'available_filter_functions' entry\n"); | |
1557 | ||
eb9a7bf0 AS |
1558 | entry = debugfs_create_file("failures", 0444, |
1559 | d_tracer, NULL, &ftrace_failures_fops); | |
1560 | if (!entry) | |
1561 | pr_warning("Could not create debugfs 'failures' entry\n"); | |
1562 | ||
5072c59f SR |
1563 | entry = debugfs_create_file("set_ftrace_filter", 0644, d_tracer, |
1564 | NULL, &ftrace_filter_fops); | |
1565 | if (!entry) | |
1566 | pr_warning("Could not create debugfs " | |
1567 | "'set_ftrace_filter' entry\n"); | |
41c52c0d SR |
1568 | |
1569 | entry = debugfs_create_file("set_ftrace_notrace", 0644, d_tracer, | |
1570 | NULL, &ftrace_notrace_fops); | |
1571 | if (!entry) | |
1572 | pr_warning("Could not create debugfs " | |
1573 | "'set_ftrace_notrace' entry\n"); | |
ad90c0e3 | 1574 | |
ea4e2bc4 SR |
1575 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
1576 | entry = debugfs_create_file("set_graph_function", 0444, d_tracer, | |
1577 | NULL, | |
1578 | &ftrace_graph_fops); | |
1579 | if (!entry) | |
1580 | pr_warning("Could not create debugfs " | |
1581 | "'set_graph_function' entry\n"); | |
1582 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
1583 | ||
5072c59f SR |
1584 | return 0; |
1585 | } | |
1586 | ||
31e88909 SR |
1587 | static int ftrace_convert_nops(struct module *mod, |
1588 | unsigned long *start, | |
68bf21aa SR |
1589 | unsigned long *end) |
1590 | { | |
1591 | unsigned long *p; | |
1592 | unsigned long addr; | |
1593 | unsigned long flags; | |
1594 | ||
08f5ac90 | 1595 | mutex_lock(&ftrace_start_lock); |
68bf21aa SR |
1596 | p = start; |
1597 | while (p < end) { | |
1598 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
1599 | /* |
1600 | * Some architecture linkers will pad between | |
1601 | * the different mcount_loc sections of different | |
1602 | * object files to satisfy alignments. | |
1603 | * Skip any NULL pointers. | |
1604 | */ | |
1605 | if (!addr) | |
1606 | continue; | |
68bf21aa | 1607 | ftrace_record_ip(addr); |
68bf21aa SR |
1608 | } |
1609 | ||
08f5ac90 | 1610 | /* disable interrupts to prevent kstop machine */ |
68bf21aa | 1611 | local_irq_save(flags); |
31e88909 | 1612 | ftrace_update_code(mod); |
68bf21aa | 1613 | local_irq_restore(flags); |
08f5ac90 | 1614 | mutex_unlock(&ftrace_start_lock); |
68bf21aa SR |
1615 | |
1616 | return 0; | |
1617 | } | |
1618 | ||
31e88909 SR |
1619 | void ftrace_init_module(struct module *mod, |
1620 | unsigned long *start, unsigned long *end) | |
90d595fe | 1621 | { |
00fd61ae | 1622 | if (ftrace_disabled || start == end) |
fed1939c | 1623 | return; |
31e88909 | 1624 | ftrace_convert_nops(mod, start, end); |
90d595fe SR |
1625 | } |
1626 | ||
68bf21aa SR |
1627 | extern unsigned long __start_mcount_loc[]; |
1628 | extern unsigned long __stop_mcount_loc[]; | |
1629 | ||
1630 | void __init ftrace_init(void) | |
1631 | { | |
1632 | unsigned long count, addr, flags; | |
1633 | int ret; | |
1634 | ||
1635 | /* Keep the ftrace pointer to the stub */ | |
1636 | addr = (unsigned long)ftrace_stub; | |
1637 | ||
1638 | local_irq_save(flags); | |
1639 | ftrace_dyn_arch_init(&addr); | |
1640 | local_irq_restore(flags); | |
1641 | ||
1642 | /* ftrace_dyn_arch_init places the return code in addr */ | |
1643 | if (addr) | |
1644 | goto failed; | |
1645 | ||
1646 | count = __stop_mcount_loc - __start_mcount_loc; | |
1647 | ||
1648 | ret = ftrace_dyn_table_alloc(count); | |
1649 | if (ret) | |
1650 | goto failed; | |
1651 | ||
1652 | last_ftrace_enabled = ftrace_enabled = 1; | |
1653 | ||
31e88909 SR |
1654 | ret = ftrace_convert_nops(NULL, |
1655 | __start_mcount_loc, | |
68bf21aa SR |
1656 | __stop_mcount_loc); |
1657 | ||
1658 | return; | |
1659 | failed: | |
1660 | ftrace_disabled = 1; | |
1661 | } | |
68bf21aa | 1662 | |
3d083395 | 1663 | #else |
0b6e4d56 FW |
1664 | |
1665 | static int __init ftrace_nodyn_init(void) | |
1666 | { | |
1667 | ftrace_enabled = 1; | |
1668 | return 0; | |
1669 | } | |
1670 | device_initcall(ftrace_nodyn_init); | |
1671 | ||
df4fc315 SR |
1672 | static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } |
1673 | static inline void ftrace_startup_enable(int command) { } | |
5a45cfe1 SR |
1674 | /* Keep as macros so we do not need to define the commands */ |
1675 | # define ftrace_startup(command) do { } while (0) | |
1676 | # define ftrace_shutdown(command) do { } while (0) | |
c7aafc54 IM |
1677 | # define ftrace_startup_sysctl() do { } while (0) |
1678 | # define ftrace_shutdown_sysctl() do { } while (0) | |
3d083395 SR |
1679 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
1680 | ||
df4fc315 SR |
1681 | static ssize_t |
1682 | ftrace_pid_read(struct file *file, char __user *ubuf, | |
1683 | size_t cnt, loff_t *ppos) | |
1684 | { | |
1685 | char buf[64]; | |
1686 | int r; | |
1687 | ||
e32d8956 SR |
1688 | if (ftrace_pid_trace == ftrace_swapper_pid) |
1689 | r = sprintf(buf, "swapper tasks\n"); | |
1690 | else if (ftrace_pid_trace) | |
978f3a45 | 1691 | r = sprintf(buf, "%u\n", pid_nr(ftrace_pid_trace)); |
df4fc315 SR |
1692 | else |
1693 | r = sprintf(buf, "no pid\n"); | |
1694 | ||
1695 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
1696 | } | |
1697 | ||
e32d8956 | 1698 | static void clear_ftrace_swapper(void) |
978f3a45 SR |
1699 | { |
1700 | struct task_struct *p; | |
e32d8956 | 1701 | int cpu; |
978f3a45 | 1702 | |
e32d8956 SR |
1703 | get_online_cpus(); |
1704 | for_each_online_cpu(cpu) { | |
1705 | p = idle_task(cpu); | |
978f3a45 | 1706 | clear_tsk_trace_trace(p); |
e32d8956 SR |
1707 | } |
1708 | put_online_cpus(); | |
1709 | } | |
978f3a45 | 1710 | |
e32d8956 SR |
1711 | static void set_ftrace_swapper(void) |
1712 | { | |
1713 | struct task_struct *p; | |
1714 | int cpu; | |
1715 | ||
1716 | get_online_cpus(); | |
1717 | for_each_online_cpu(cpu) { | |
1718 | p = idle_task(cpu); | |
1719 | set_tsk_trace_trace(p); | |
1720 | } | |
1721 | put_online_cpus(); | |
978f3a45 SR |
1722 | } |
1723 | ||
e32d8956 SR |
1724 | static void clear_ftrace_pid(struct pid *pid) |
1725 | { | |
1726 | struct task_struct *p; | |
1727 | ||
1728 | do_each_pid_task(pid, PIDTYPE_PID, p) { | |
1729 | clear_tsk_trace_trace(p); | |
1730 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
1731 | put_pid(pid); | |
1732 | } | |
1733 | ||
1734 | static void set_ftrace_pid(struct pid *pid) | |
978f3a45 SR |
1735 | { |
1736 | struct task_struct *p; | |
1737 | ||
1738 | do_each_pid_task(pid, PIDTYPE_PID, p) { | |
1739 | set_tsk_trace_trace(p); | |
1740 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
1741 | } | |
1742 | ||
e32d8956 SR |
1743 | static void clear_ftrace_pid_task(struct pid **pid) |
1744 | { | |
1745 | if (*pid == ftrace_swapper_pid) | |
1746 | clear_ftrace_swapper(); | |
1747 | else | |
1748 | clear_ftrace_pid(*pid); | |
1749 | ||
1750 | *pid = NULL; | |
1751 | } | |
1752 | ||
1753 | static void set_ftrace_pid_task(struct pid *pid) | |
1754 | { | |
1755 | if (pid == ftrace_swapper_pid) | |
1756 | set_ftrace_swapper(); | |
1757 | else | |
1758 | set_ftrace_pid(pid); | |
1759 | } | |
1760 | ||
df4fc315 SR |
1761 | static ssize_t |
1762 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
1763 | size_t cnt, loff_t *ppos) | |
1764 | { | |
978f3a45 | 1765 | struct pid *pid; |
df4fc315 SR |
1766 | char buf[64]; |
1767 | long val; | |
1768 | int ret; | |
1769 | ||
1770 | if (cnt >= sizeof(buf)) | |
1771 | return -EINVAL; | |
1772 | ||
1773 | if (copy_from_user(&buf, ubuf, cnt)) | |
1774 | return -EFAULT; | |
1775 | ||
1776 | buf[cnt] = 0; | |
1777 | ||
1778 | ret = strict_strtol(buf, 10, &val); | |
1779 | if (ret < 0) | |
1780 | return ret; | |
1781 | ||
1782 | mutex_lock(&ftrace_start_lock); | |
978f3a45 | 1783 | if (val < 0) { |
df4fc315 | 1784 | /* disable pid tracing */ |
978f3a45 | 1785 | if (!ftrace_pid_trace) |
df4fc315 | 1786 | goto out; |
978f3a45 SR |
1787 | |
1788 | clear_ftrace_pid_task(&ftrace_pid_trace); | |
df4fc315 SR |
1789 | |
1790 | } else { | |
e32d8956 SR |
1791 | /* swapper task is special */ |
1792 | if (!val) { | |
1793 | pid = ftrace_swapper_pid; | |
1794 | if (pid == ftrace_pid_trace) | |
1795 | goto out; | |
1796 | } else { | |
1797 | pid = find_get_pid(val); | |
df4fc315 | 1798 | |
e32d8956 SR |
1799 | if (pid == ftrace_pid_trace) { |
1800 | put_pid(pid); | |
1801 | goto out; | |
1802 | } | |
0ef8cde5 | 1803 | } |
0ef8cde5 | 1804 | |
978f3a45 SR |
1805 | if (ftrace_pid_trace) |
1806 | clear_ftrace_pid_task(&ftrace_pid_trace); | |
1807 | ||
1808 | if (!pid) | |
1809 | goto out; | |
1810 | ||
1811 | ftrace_pid_trace = pid; | |
1812 | ||
1813 | set_ftrace_pid_task(ftrace_pid_trace); | |
df4fc315 SR |
1814 | } |
1815 | ||
1816 | /* update the function call */ | |
1817 | ftrace_update_pid_func(); | |
1818 | ftrace_startup_enable(0); | |
1819 | ||
1820 | out: | |
1821 | mutex_unlock(&ftrace_start_lock); | |
1822 | ||
1823 | return cnt; | |
1824 | } | |
1825 | ||
1826 | static struct file_operations ftrace_pid_fops = { | |
1827 | .read = ftrace_pid_read, | |
1828 | .write = ftrace_pid_write, | |
1829 | }; | |
1830 | ||
1831 | static __init int ftrace_init_debugfs(void) | |
1832 | { | |
1833 | struct dentry *d_tracer; | |
1834 | struct dentry *entry; | |
1835 | ||
1836 | d_tracer = tracing_init_dentry(); | |
1837 | if (!d_tracer) | |
1838 | return 0; | |
1839 | ||
1840 | ftrace_init_dyn_debugfs(d_tracer); | |
1841 | ||
1842 | entry = debugfs_create_file("set_ftrace_pid", 0644, d_tracer, | |
1843 | NULL, &ftrace_pid_fops); | |
1844 | if (!entry) | |
1845 | pr_warning("Could not create debugfs " | |
1846 | "'set_ftrace_pid' entry\n"); | |
1847 | return 0; | |
1848 | } | |
1849 | ||
1850 | fs_initcall(ftrace_init_debugfs); | |
1851 | ||
a2bb6a3d | 1852 | /** |
81adbdc0 | 1853 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
1854 | * |
1855 | * This function should be used by panic code. It stops ftrace | |
1856 | * but in a not so nice way. If you need to simply kill ftrace | |
1857 | * from a non-atomic section, use ftrace_kill. | |
1858 | */ | |
81adbdc0 | 1859 | void ftrace_kill(void) |
a2bb6a3d SR |
1860 | { |
1861 | ftrace_disabled = 1; | |
1862 | ftrace_enabled = 0; | |
a2bb6a3d SR |
1863 | clear_ftrace_function(); |
1864 | } | |
1865 | ||
16444a8a | 1866 | /** |
3d083395 SR |
1867 | * register_ftrace_function - register a function for profiling |
1868 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 1869 | * |
3d083395 SR |
1870 | * Register a function to be called by all functions in the |
1871 | * kernel. | |
1872 | * | |
1873 | * Note: @ops->func and all the functions it calls must be labeled | |
1874 | * with "notrace", otherwise it will go into a | |
1875 | * recursive loop. | |
16444a8a | 1876 | */ |
3d083395 | 1877 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 1878 | { |
b0fc494f SR |
1879 | int ret; |
1880 | ||
4eebcc81 SR |
1881 | if (unlikely(ftrace_disabled)) |
1882 | return -1; | |
1883 | ||
b0fc494f | 1884 | mutex_lock(&ftrace_sysctl_lock); |
e7d3737e | 1885 | |
b0fc494f | 1886 | ret = __register_ftrace_function(ops); |
5a45cfe1 | 1887 | ftrace_startup(0); |
b0fc494f | 1888 | |
e7d3737e | 1889 | mutex_unlock(&ftrace_sysctl_lock); |
b0fc494f | 1890 | return ret; |
3d083395 SR |
1891 | } |
1892 | ||
1893 | /** | |
1894 | * unregister_ftrace_function - unresgister a function for profiling. | |
1895 | * @ops - ops structure that holds the function to unregister | |
1896 | * | |
1897 | * Unregister a function that was added to be called by ftrace profiling. | |
1898 | */ | |
1899 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
1900 | { | |
1901 | int ret; | |
1902 | ||
b0fc494f | 1903 | mutex_lock(&ftrace_sysctl_lock); |
3d083395 | 1904 | ret = __unregister_ftrace_function(ops); |
5a45cfe1 | 1905 | ftrace_shutdown(0); |
b0fc494f SR |
1906 | mutex_unlock(&ftrace_sysctl_lock); |
1907 | ||
1908 | return ret; | |
1909 | } | |
1910 | ||
e309b41d | 1911 | int |
b0fc494f | 1912 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
5072c59f | 1913 | struct file *file, void __user *buffer, size_t *lenp, |
b0fc494f SR |
1914 | loff_t *ppos) |
1915 | { | |
1916 | int ret; | |
1917 | ||
4eebcc81 SR |
1918 | if (unlikely(ftrace_disabled)) |
1919 | return -ENODEV; | |
1920 | ||
b0fc494f SR |
1921 | mutex_lock(&ftrace_sysctl_lock); |
1922 | ||
5072c59f | 1923 | ret = proc_dointvec(table, write, file, buffer, lenp, ppos); |
b0fc494f SR |
1924 | |
1925 | if (ret || !write || (last_ftrace_enabled == ftrace_enabled)) | |
1926 | goto out; | |
1927 | ||
1928 | last_ftrace_enabled = ftrace_enabled; | |
1929 | ||
1930 | if (ftrace_enabled) { | |
1931 | ||
1932 | ftrace_startup_sysctl(); | |
1933 | ||
1934 | /* we are starting ftrace again */ | |
1935 | if (ftrace_list != &ftrace_list_end) { | |
1936 | if (ftrace_list->next == &ftrace_list_end) | |
1937 | ftrace_trace_function = ftrace_list->func; | |
1938 | else | |
1939 | ftrace_trace_function = ftrace_list_func; | |
1940 | } | |
1941 | ||
1942 | } else { | |
1943 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
1944 | ftrace_trace_function = ftrace_stub; | |
1945 | ||
1946 | ftrace_shutdown_sysctl(); | |
1947 | } | |
1948 | ||
1949 | out: | |
1950 | mutex_unlock(&ftrace_sysctl_lock); | |
3d083395 | 1951 | return ret; |
16444a8a | 1952 | } |
f17845e5 | 1953 | |
fb52607a | 1954 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 1955 | |
287b6e68 | 1956 | static atomic_t ftrace_graph_active; |
e7d3737e | 1957 | |
e49dc19c SR |
1958 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
1959 | { | |
1960 | return 0; | |
1961 | } | |
1962 | ||
287b6e68 FW |
1963 | /* The callbacks that hook a function */ |
1964 | trace_func_graph_ret_t ftrace_graph_return = | |
1965 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 1966 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
1967 | |
1968 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
1969 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
1970 | { | |
1971 | int i; | |
1972 | int ret = 0; | |
1973 | unsigned long flags; | |
1974 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; | |
1975 | struct task_struct *g, *t; | |
1976 | ||
1977 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
1978 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
1979 | * sizeof(struct ftrace_ret_stack), | |
1980 | GFP_KERNEL); | |
1981 | if (!ret_stack_list[i]) { | |
1982 | start = 0; | |
1983 | end = i; | |
1984 | ret = -ENOMEM; | |
1985 | goto free; | |
1986 | } | |
1987 | } | |
1988 | ||
1989 | read_lock_irqsave(&tasklist_lock, flags); | |
1990 | do_each_thread(g, t) { | |
1991 | if (start == end) { | |
1992 | ret = -EAGAIN; | |
1993 | goto unlock; | |
1994 | } | |
1995 | ||
1996 | if (t->ret_stack == NULL) { | |
f201ae23 | 1997 | t->curr_ret_stack = -1; |
48d68b20 FW |
1998 | /* Make sure IRQs see the -1 first: */ |
1999 | barrier(); | |
2000 | t->ret_stack = ret_stack_list[start++]; | |
f201ae23 FW |
2001 | atomic_set(&t->trace_overrun, 0); |
2002 | } | |
2003 | } while_each_thread(g, t); | |
2004 | ||
2005 | unlock: | |
2006 | read_unlock_irqrestore(&tasklist_lock, flags); | |
2007 | free: | |
2008 | for (i = start; i < end; i++) | |
2009 | kfree(ret_stack_list[i]); | |
2010 | return ret; | |
2011 | } | |
2012 | ||
2013 | /* Allocate a return stack for each task */ | |
fb52607a | 2014 | static int start_graph_tracing(void) |
f201ae23 FW |
2015 | { |
2016 | struct ftrace_ret_stack **ret_stack_list; | |
2017 | int ret; | |
2018 | ||
2019 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
2020 | sizeof(struct ftrace_ret_stack *), | |
2021 | GFP_KERNEL); | |
2022 | ||
2023 | if (!ret_stack_list) | |
2024 | return -ENOMEM; | |
2025 | ||
2026 | do { | |
2027 | ret = alloc_retstack_tasklist(ret_stack_list); | |
2028 | } while (ret == -EAGAIN); | |
2029 | ||
2030 | kfree(ret_stack_list); | |
2031 | return ret; | |
2032 | } | |
2033 | ||
287b6e68 FW |
2034 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
2035 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 2036 | { |
e7d3737e FW |
2037 | int ret = 0; |
2038 | ||
2039 | mutex_lock(&ftrace_sysctl_lock); | |
2040 | ||
287b6e68 | 2041 | atomic_inc(&ftrace_graph_active); |
fb52607a | 2042 | ret = start_graph_tracing(); |
f201ae23 | 2043 | if (ret) { |
287b6e68 | 2044 | atomic_dec(&ftrace_graph_active); |
f201ae23 FW |
2045 | goto out; |
2046 | } | |
e53a6319 | 2047 | |
287b6e68 FW |
2048 | ftrace_graph_return = retfunc; |
2049 | ftrace_graph_entry = entryfunc; | |
e53a6319 | 2050 | |
5a45cfe1 | 2051 | ftrace_startup(FTRACE_START_FUNC_RET); |
e7d3737e FW |
2052 | |
2053 | out: | |
2054 | mutex_unlock(&ftrace_sysctl_lock); | |
2055 | return ret; | |
15e6cb36 FW |
2056 | } |
2057 | ||
fb52607a | 2058 | void unregister_ftrace_graph(void) |
15e6cb36 | 2059 | { |
e7d3737e FW |
2060 | mutex_lock(&ftrace_sysctl_lock); |
2061 | ||
287b6e68 FW |
2062 | atomic_dec(&ftrace_graph_active); |
2063 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 2064 | ftrace_graph_entry = ftrace_graph_entry_stub; |
5a45cfe1 | 2065 | ftrace_shutdown(FTRACE_STOP_FUNC_RET); |
e7d3737e FW |
2066 | |
2067 | mutex_unlock(&ftrace_sysctl_lock); | |
15e6cb36 | 2068 | } |
f201ae23 FW |
2069 | |
2070 | /* Allocate a return stack for newly created task */ | |
fb52607a | 2071 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 2072 | { |
287b6e68 | 2073 | if (atomic_read(&ftrace_graph_active)) { |
f201ae23 FW |
2074 | t->ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH |
2075 | * sizeof(struct ftrace_ret_stack), | |
2076 | GFP_KERNEL); | |
2077 | if (!t->ret_stack) | |
2078 | return; | |
2079 | t->curr_ret_stack = -1; | |
2080 | atomic_set(&t->trace_overrun, 0); | |
2081 | } else | |
2082 | t->ret_stack = NULL; | |
2083 | } | |
2084 | ||
fb52607a | 2085 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 2086 | { |
eae849ca FW |
2087 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
2088 | ||
f201ae23 | 2089 | t->ret_stack = NULL; |
eae849ca FW |
2090 | /* NULL must become visible to IRQs before we free it: */ |
2091 | barrier(); | |
2092 | ||
2093 | kfree(ret_stack); | |
f201ae23 | 2094 | } |
14a866c5 SR |
2095 | |
2096 | void ftrace_graph_stop(void) | |
2097 | { | |
2098 | ftrace_stop(); | |
2099 | } | |
15e6cb36 FW |
2100 | #endif |
2101 |