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 | 19 | #include <linux/seq_file.h> |
00f57f54 | 20 | #include <linux/suspend.h> |
5072c59f | 21 | #include <linux/debugfs.h> |
3d083395 | 22 | #include <linux/hardirq.h> |
2d8b820b | 23 | #include <linux/kthread.h> |
5072c59f | 24 | #include <linux/uaccess.h> |
f22f9a89 | 25 | #include <linux/kprobes.h> |
2d8b820b | 26 | #include <linux/ftrace.h> |
b0fc494f | 27 | #include <linux/sysctl.h> |
5072c59f | 28 | #include <linux/ctype.h> |
3d083395 SR |
29 | #include <linux/list.h> |
30 | ||
395a59d0 AS |
31 | #include <asm/ftrace.h> |
32 | ||
3d083395 | 33 | #include "trace.h" |
16444a8a | 34 | |
6912896e SR |
35 | #define FTRACE_WARN_ON(cond) \ |
36 | do { \ | |
37 | if (WARN_ON(cond)) \ | |
38 | ftrace_kill(); \ | |
39 | } while (0) | |
40 | ||
41 | #define FTRACE_WARN_ON_ONCE(cond) \ | |
42 | do { \ | |
43 | if (WARN_ON_ONCE(cond)) \ | |
44 | ftrace_kill(); \ | |
45 | } while (0) | |
46 | ||
4eebcc81 SR |
47 | /* ftrace_enabled is a method to turn ftrace on or off */ |
48 | int ftrace_enabled __read_mostly; | |
d61f82d0 | 49 | static int last_ftrace_enabled; |
b0fc494f | 50 | |
0ef8cde5 | 51 | /* set when tracing only a pid */ |
978f3a45 | 52 | struct pid *ftrace_pid_trace; |
21bbecda | 53 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; |
df4fc315 | 54 | |
60a7ecf4 SR |
55 | /* Quick disabling of function tracer. */ |
56 | int function_trace_stop; | |
57 | ||
4eebcc81 SR |
58 | /* |
59 | * ftrace_disabled is set when an anomaly is discovered. | |
60 | * ftrace_disabled is much stronger than ftrace_enabled. | |
61 | */ | |
62 | static int ftrace_disabled __read_mostly; | |
63 | ||
3d083395 | 64 | static DEFINE_SPINLOCK(ftrace_lock); |
b0fc494f | 65 | static DEFINE_MUTEX(ftrace_sysctl_lock); |
df4fc315 | 66 | static DEFINE_MUTEX(ftrace_start_lock); |
b0fc494f | 67 | |
16444a8a ACM |
68 | static struct ftrace_ops ftrace_list_end __read_mostly = |
69 | { | |
70 | .func = ftrace_stub, | |
71 | }; | |
72 | ||
73 | static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end; | |
74 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; | |
60a7ecf4 | 75 | ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub; |
df4fc315 | 76 | ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub; |
16444a8a | 77 | |
f2252935 | 78 | static void ftrace_list_func(unsigned long ip, unsigned long parent_ip) |
16444a8a ACM |
79 | { |
80 | struct ftrace_ops *op = ftrace_list; | |
81 | ||
82 | /* in case someone actually ports this to alpha! */ | |
83 | read_barrier_depends(); | |
84 | ||
85 | while (op != &ftrace_list_end) { | |
86 | /* silly alpha */ | |
87 | read_barrier_depends(); | |
88 | op->func(ip, parent_ip); | |
89 | op = op->next; | |
90 | }; | |
91 | } | |
92 | ||
df4fc315 SR |
93 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip) |
94 | { | |
0ef8cde5 | 95 | if (!test_tsk_trace_trace(current)) |
df4fc315 SR |
96 | return; |
97 | ||
98 | ftrace_pid_function(ip, parent_ip); | |
99 | } | |
100 | ||
101 | static void set_ftrace_pid_function(ftrace_func_t func) | |
102 | { | |
103 | /* do not set ftrace_pid_function to itself! */ | |
104 | if (func != ftrace_pid_func) | |
105 | ftrace_pid_function = func; | |
106 | } | |
107 | ||
16444a8a | 108 | /** |
3d083395 | 109 | * clear_ftrace_function - reset the ftrace function |
16444a8a | 110 | * |
3d083395 SR |
111 | * This NULLs the ftrace function and in essence stops |
112 | * tracing. There may be lag | |
16444a8a | 113 | */ |
3d083395 | 114 | void clear_ftrace_function(void) |
16444a8a | 115 | { |
3d083395 | 116 | ftrace_trace_function = ftrace_stub; |
60a7ecf4 | 117 | __ftrace_trace_function = ftrace_stub; |
df4fc315 | 118 | ftrace_pid_function = ftrace_stub; |
3d083395 SR |
119 | } |
120 | ||
60a7ecf4 SR |
121 | #ifndef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
122 | /* | |
123 | * For those archs that do not test ftrace_trace_stop in their | |
124 | * mcount call site, we need to do it from C. | |
125 | */ | |
126 | static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip) | |
127 | { | |
128 | if (function_trace_stop) | |
129 | return; | |
130 | ||
131 | __ftrace_trace_function(ip, parent_ip); | |
132 | } | |
133 | #endif | |
134 | ||
e309b41d | 135 | static int __register_ftrace_function(struct ftrace_ops *ops) |
3d083395 | 136 | { |
99ecdc43 | 137 | /* should not be called from interrupt context */ |
3d083395 | 138 | spin_lock(&ftrace_lock); |
16444a8a | 139 | |
16444a8a ACM |
140 | ops->next = ftrace_list; |
141 | /* | |
142 | * We are entering ops into the ftrace_list but another | |
143 | * CPU might be walking that list. We need to make sure | |
144 | * the ops->next pointer is valid before another CPU sees | |
145 | * the ops pointer included into the ftrace_list. | |
146 | */ | |
147 | smp_wmb(); | |
148 | ftrace_list = ops; | |
3d083395 | 149 | |
b0fc494f | 150 | if (ftrace_enabled) { |
df4fc315 SR |
151 | ftrace_func_t func; |
152 | ||
153 | if (ops->next == &ftrace_list_end) | |
154 | func = ops->func; | |
155 | else | |
156 | func = ftrace_list_func; | |
157 | ||
978f3a45 | 158 | if (ftrace_pid_trace) { |
df4fc315 SR |
159 | set_ftrace_pid_function(func); |
160 | func = ftrace_pid_func; | |
161 | } | |
162 | ||
b0fc494f SR |
163 | /* |
164 | * For one func, simply call it directly. | |
165 | * For more than one func, call the chain. | |
166 | */ | |
60a7ecf4 | 167 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
df4fc315 | 168 | ftrace_trace_function = func; |
60a7ecf4 | 169 | #else |
df4fc315 | 170 | __ftrace_trace_function = func; |
60a7ecf4 SR |
171 | ftrace_trace_function = ftrace_test_stop_func; |
172 | #endif | |
b0fc494f | 173 | } |
3d083395 SR |
174 | |
175 | spin_unlock(&ftrace_lock); | |
16444a8a ACM |
176 | |
177 | return 0; | |
178 | } | |
179 | ||
e309b41d | 180 | static int __unregister_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 181 | { |
16444a8a ACM |
182 | struct ftrace_ops **p; |
183 | int ret = 0; | |
184 | ||
99ecdc43 | 185 | /* should not be called from interrupt context */ |
3d083395 | 186 | spin_lock(&ftrace_lock); |
16444a8a ACM |
187 | |
188 | /* | |
3d083395 SR |
189 | * If we are removing the last function, then simply point |
190 | * to the ftrace_stub. | |
16444a8a ACM |
191 | */ |
192 | if (ftrace_list == ops && ops->next == &ftrace_list_end) { | |
193 | ftrace_trace_function = ftrace_stub; | |
194 | ftrace_list = &ftrace_list_end; | |
195 | goto out; | |
196 | } | |
197 | ||
198 | for (p = &ftrace_list; *p != &ftrace_list_end; p = &(*p)->next) | |
199 | if (*p == ops) | |
200 | break; | |
201 | ||
202 | if (*p != ops) { | |
203 | ret = -1; | |
204 | goto out; | |
205 | } | |
206 | ||
207 | *p = (*p)->next; | |
208 | ||
b0fc494f SR |
209 | if (ftrace_enabled) { |
210 | /* If we only have one func left, then call that directly */ | |
df4fc315 SR |
211 | if (ftrace_list->next == &ftrace_list_end) { |
212 | ftrace_func_t func = ftrace_list->func; | |
213 | ||
978f3a45 | 214 | if (ftrace_pid_trace) { |
df4fc315 SR |
215 | set_ftrace_pid_function(func); |
216 | func = ftrace_pid_func; | |
217 | } | |
218 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST | |
219 | ftrace_trace_function = func; | |
220 | #else | |
221 | __ftrace_trace_function = func; | |
222 | #endif | |
223 | } | |
b0fc494f | 224 | } |
16444a8a ACM |
225 | |
226 | out: | |
3d083395 SR |
227 | spin_unlock(&ftrace_lock); |
228 | ||
229 | return ret; | |
230 | } | |
231 | ||
df4fc315 SR |
232 | static void ftrace_update_pid_func(void) |
233 | { | |
234 | ftrace_func_t func; | |
235 | ||
236 | /* should not be called from interrupt context */ | |
237 | spin_lock(&ftrace_lock); | |
238 | ||
239 | if (ftrace_trace_function == ftrace_stub) | |
240 | goto out; | |
241 | ||
242 | func = ftrace_trace_function; | |
243 | ||
978f3a45 | 244 | if (ftrace_pid_trace) { |
df4fc315 SR |
245 | set_ftrace_pid_function(func); |
246 | func = ftrace_pid_func; | |
247 | } else { | |
66eafebc LW |
248 | if (func == ftrace_pid_func) |
249 | func = ftrace_pid_function; | |
df4fc315 SR |
250 | } |
251 | ||
252 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST | |
253 | ftrace_trace_function = func; | |
254 | #else | |
255 | __ftrace_trace_function = func; | |
256 | #endif | |
257 | ||
258 | out: | |
259 | spin_unlock(&ftrace_lock); | |
260 | } | |
261 | ||
3d083395 | 262 | #ifdef CONFIG_DYNAMIC_FTRACE |
99ecdc43 | 263 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD |
cb7be3b2 | 264 | # error Dynamic ftrace depends on MCOUNT_RECORD |
99ecdc43 SR |
265 | #endif |
266 | ||
71c67d58 SN |
267 | /* |
268 | * Since MCOUNT_ADDR may point to mcount itself, we do not want | |
269 | * to get it confused by reading a reference in the code as we | |
270 | * are parsing on objcopy output of text. Use a variable for | |
271 | * it instead. | |
272 | */ | |
273 | static unsigned long mcount_addr = MCOUNT_ADDR; | |
274 | ||
d61f82d0 SR |
275 | enum { |
276 | FTRACE_ENABLE_CALLS = (1 << 0), | |
277 | FTRACE_DISABLE_CALLS = (1 << 1), | |
278 | FTRACE_UPDATE_TRACE_FUNC = (1 << 2), | |
279 | FTRACE_ENABLE_MCOUNT = (1 << 3), | |
280 | FTRACE_DISABLE_MCOUNT = (1 << 4), | |
5a45cfe1 SR |
281 | FTRACE_START_FUNC_RET = (1 << 5), |
282 | FTRACE_STOP_FUNC_RET = (1 << 6), | |
d61f82d0 SR |
283 | }; |
284 | ||
5072c59f SR |
285 | static int ftrace_filtered; |
286 | ||
08f5ac90 | 287 | static LIST_HEAD(ftrace_new_addrs); |
3d083395 | 288 | |
41c52c0d | 289 | static DEFINE_MUTEX(ftrace_regex_lock); |
3d083395 | 290 | |
3c1720f0 SR |
291 | struct ftrace_page { |
292 | struct ftrace_page *next; | |
aa5e5cea | 293 | unsigned long index; |
3c1720f0 | 294 | struct dyn_ftrace records[]; |
aa5e5cea | 295 | }; |
3c1720f0 SR |
296 | |
297 | #define ENTRIES_PER_PAGE \ | |
298 | ((PAGE_SIZE - sizeof(struct ftrace_page)) / sizeof(struct dyn_ftrace)) | |
299 | ||
300 | /* estimate from running different kernels */ | |
301 | #define NR_TO_INIT 10000 | |
302 | ||
303 | static struct ftrace_page *ftrace_pages_start; | |
304 | static struct ftrace_page *ftrace_pages; | |
305 | ||
37ad5084 SR |
306 | static struct dyn_ftrace *ftrace_free_records; |
307 | ||
ecea656d AS |
308 | |
309 | #ifdef CONFIG_KPROBES | |
f17845e5 IM |
310 | |
311 | static int frozen_record_count; | |
312 | ||
ecea656d AS |
313 | static inline void freeze_record(struct dyn_ftrace *rec) |
314 | { | |
315 | if (!(rec->flags & FTRACE_FL_FROZEN)) { | |
316 | rec->flags |= FTRACE_FL_FROZEN; | |
317 | frozen_record_count++; | |
318 | } | |
319 | } | |
320 | ||
321 | static inline void unfreeze_record(struct dyn_ftrace *rec) | |
322 | { | |
323 | if (rec->flags & FTRACE_FL_FROZEN) { | |
324 | rec->flags &= ~FTRACE_FL_FROZEN; | |
325 | frozen_record_count--; | |
326 | } | |
327 | } | |
328 | ||
329 | static inline int record_frozen(struct dyn_ftrace *rec) | |
330 | { | |
331 | return rec->flags & FTRACE_FL_FROZEN; | |
332 | } | |
333 | #else | |
334 | # define freeze_record(rec) ({ 0; }) | |
335 | # define unfreeze_record(rec) ({ 0; }) | |
336 | # define record_frozen(rec) ({ 0; }) | |
337 | #endif /* CONFIG_KPROBES */ | |
338 | ||
e309b41d | 339 | static void ftrace_free_rec(struct dyn_ftrace *rec) |
37ad5084 | 340 | { |
37ad5084 SR |
341 | rec->ip = (unsigned long)ftrace_free_records; |
342 | ftrace_free_records = rec; | |
343 | rec->flags |= FTRACE_FL_FREE; | |
344 | } | |
345 | ||
fed1939c SR |
346 | void ftrace_release(void *start, unsigned long size) |
347 | { | |
348 | struct dyn_ftrace *rec; | |
349 | struct ftrace_page *pg; | |
350 | unsigned long s = (unsigned long)start; | |
351 | unsigned long e = s + size; | |
352 | int i; | |
353 | ||
00fd61ae | 354 | if (ftrace_disabled || !start) |
fed1939c SR |
355 | return; |
356 | ||
99ecdc43 | 357 | /* should not be called from interrupt context */ |
fed1939c SR |
358 | spin_lock(&ftrace_lock); |
359 | ||
360 | for (pg = ftrace_pages_start; pg; pg = pg->next) { | |
361 | for (i = 0; i < pg->index; i++) { | |
362 | rec = &pg->records[i]; | |
363 | ||
364 | if ((rec->ip >= s) && (rec->ip < e)) | |
365 | ftrace_free_rec(rec); | |
366 | } | |
367 | } | |
368 | spin_unlock(&ftrace_lock); | |
fed1939c SR |
369 | } |
370 | ||
e309b41d | 371 | static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip) |
3c1720f0 | 372 | { |
37ad5084 SR |
373 | struct dyn_ftrace *rec; |
374 | ||
375 | /* First check for freed records */ | |
376 | if (ftrace_free_records) { | |
377 | rec = ftrace_free_records; | |
378 | ||
37ad5084 | 379 | if (unlikely(!(rec->flags & FTRACE_FL_FREE))) { |
6912896e | 380 | FTRACE_WARN_ON_ONCE(1); |
37ad5084 SR |
381 | ftrace_free_records = NULL; |
382 | return NULL; | |
383 | } | |
384 | ||
385 | ftrace_free_records = (void *)rec->ip; | |
386 | memset(rec, 0, sizeof(*rec)); | |
387 | return rec; | |
388 | } | |
389 | ||
3c1720f0 | 390 | if (ftrace_pages->index == ENTRIES_PER_PAGE) { |
08f5ac90 SR |
391 | if (!ftrace_pages->next) { |
392 | /* allocate another page */ | |
393 | ftrace_pages->next = | |
394 | (void *)get_zeroed_page(GFP_KERNEL); | |
395 | if (!ftrace_pages->next) | |
396 | return NULL; | |
397 | } | |
3c1720f0 SR |
398 | ftrace_pages = ftrace_pages->next; |
399 | } | |
400 | ||
401 | return &ftrace_pages->records[ftrace_pages->index++]; | |
402 | } | |
403 | ||
08f5ac90 | 404 | static struct dyn_ftrace * |
d61f82d0 | 405 | ftrace_record_ip(unsigned long ip) |
3d083395 | 406 | { |
08f5ac90 | 407 | struct dyn_ftrace *rec; |
3d083395 | 408 | |
f3c7ac40 | 409 | if (ftrace_disabled) |
08f5ac90 | 410 | return NULL; |
3d083395 | 411 | |
08f5ac90 SR |
412 | rec = ftrace_alloc_dyn_node(ip); |
413 | if (!rec) | |
414 | return NULL; | |
3d083395 | 415 | |
08f5ac90 | 416 | rec->ip = ip; |
3d083395 | 417 | |
08f5ac90 | 418 | list_add(&rec->list, &ftrace_new_addrs); |
3d083395 | 419 | |
08f5ac90 | 420 | return rec; |
3d083395 SR |
421 | } |
422 | ||
b17e8a37 SR |
423 | static void print_ip_ins(const char *fmt, unsigned char *p) |
424 | { | |
425 | int i; | |
426 | ||
427 | printk(KERN_CONT "%s", fmt); | |
428 | ||
429 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
430 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
431 | } | |
432 | ||
31e88909 | 433 | static void ftrace_bug(int failed, unsigned long ip) |
b17e8a37 SR |
434 | { |
435 | switch (failed) { | |
436 | case -EFAULT: | |
437 | FTRACE_WARN_ON_ONCE(1); | |
438 | pr_info("ftrace faulted on modifying "); | |
439 | print_ip_sym(ip); | |
440 | break; | |
441 | case -EINVAL: | |
442 | FTRACE_WARN_ON_ONCE(1); | |
443 | pr_info("ftrace failed to modify "); | |
444 | print_ip_sym(ip); | |
b17e8a37 | 445 | print_ip_ins(" actual: ", (unsigned char *)ip); |
b17e8a37 SR |
446 | printk(KERN_CONT "\n"); |
447 | break; | |
448 | case -EPERM: | |
449 | FTRACE_WARN_ON_ONCE(1); | |
450 | pr_info("ftrace faulted on writing "); | |
451 | print_ip_sym(ip); | |
452 | break; | |
453 | default: | |
454 | FTRACE_WARN_ON_ONCE(1); | |
455 | pr_info("ftrace faulted on unknown error "); | |
456 | print_ip_sym(ip); | |
457 | } | |
458 | } | |
459 | ||
3c1720f0 | 460 | |
0eb96701 | 461 | static int |
31e88909 | 462 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) |
5072c59f | 463 | { |
41c52c0d | 464 | unsigned long ip, fl; |
e7d3737e FW |
465 | unsigned long ftrace_addr; |
466 | ||
e7d3737e | 467 | ftrace_addr = (unsigned long)ftrace_caller; |
5072c59f SR |
468 | |
469 | ip = rec->ip; | |
470 | ||
982c350b SR |
471 | /* |
472 | * If this record is not to be traced and | |
473 | * it is not enabled then do nothing. | |
474 | * | |
475 | * If this record is not to be traced and | |
476 | * it is enabled then disabled it. | |
477 | * | |
478 | */ | |
479 | if (rec->flags & FTRACE_FL_NOTRACE) { | |
480 | if (rec->flags & FTRACE_FL_ENABLED) | |
481 | rec->flags &= ~FTRACE_FL_ENABLED; | |
482 | else | |
483 | return 0; | |
484 | ||
485 | } else if (ftrace_filtered && enable) { | |
5072c59f | 486 | /* |
982c350b | 487 | * Filtering is on: |
5072c59f | 488 | */ |
a4500b84 | 489 | |
982c350b | 490 | fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED); |
5072c59f | 491 | |
982c350b SR |
492 | /* Record is filtered and enabled, do nothing */ |
493 | if (fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED)) | |
0eb96701 | 494 | return 0; |
5072c59f | 495 | |
982c350b SR |
496 | /* Record is not filtered and is not enabled do nothing */ |
497 | if (!fl) | |
498 | return 0; | |
499 | ||
500 | /* Record is not filtered but enabled, disable it */ | |
501 | if (fl == FTRACE_FL_ENABLED) | |
5072c59f | 502 | rec->flags &= ~FTRACE_FL_ENABLED; |
982c350b SR |
503 | else |
504 | /* Otherwise record is filtered but not enabled, enable it */ | |
5072c59f | 505 | rec->flags |= FTRACE_FL_ENABLED; |
5072c59f | 506 | } else { |
982c350b | 507 | /* Disable or not filtered */ |
5072c59f | 508 | |
41c52c0d | 509 | if (enable) { |
982c350b | 510 | /* if record is enabled, do nothing */ |
5072c59f | 511 | if (rec->flags & FTRACE_FL_ENABLED) |
0eb96701 | 512 | return 0; |
982c350b | 513 | |
5072c59f | 514 | rec->flags |= FTRACE_FL_ENABLED; |
982c350b | 515 | |
5072c59f | 516 | } else { |
982c350b SR |
517 | |
518 | /* if record is not enabled do nothing */ | |
5072c59f | 519 | if (!(rec->flags & FTRACE_FL_ENABLED)) |
0eb96701 | 520 | return 0; |
982c350b | 521 | |
5072c59f SR |
522 | rec->flags &= ~FTRACE_FL_ENABLED; |
523 | } | |
524 | } | |
525 | ||
982c350b | 526 | if (rec->flags & FTRACE_FL_ENABLED) |
e7d3737e | 527 | return ftrace_make_call(rec, ftrace_addr); |
31e88909 | 528 | else |
e7d3737e | 529 | return ftrace_make_nop(NULL, rec, ftrace_addr); |
5072c59f SR |
530 | } |
531 | ||
e309b41d | 532 | static void ftrace_replace_code(int enable) |
3c1720f0 | 533 | { |
0eb96701 | 534 | int i, failed; |
3c1720f0 SR |
535 | struct dyn_ftrace *rec; |
536 | struct ftrace_page *pg; | |
3c1720f0 | 537 | |
3c1720f0 SR |
538 | for (pg = ftrace_pages_start; pg; pg = pg->next) { |
539 | for (i = 0; i < pg->index; i++) { | |
540 | rec = &pg->records[i]; | |
541 | ||
918c1154 SR |
542 | /* |
543 | * Skip over free records and records that have | |
544 | * failed. | |
545 | */ | |
546 | if (rec->flags & FTRACE_FL_FREE || | |
547 | rec->flags & FTRACE_FL_FAILED) | |
3c1720f0 SR |
548 | continue; |
549 | ||
f22f9a89 | 550 | /* ignore updates to this record's mcount site */ |
98a05ed4 AS |
551 | if (get_kprobe((void *)rec->ip)) { |
552 | freeze_record(rec); | |
f22f9a89 | 553 | continue; |
98a05ed4 AS |
554 | } else { |
555 | unfreeze_record(rec); | |
556 | } | |
f22f9a89 | 557 | |
31e88909 | 558 | failed = __ftrace_replace_code(rec, enable); |
0eb96701 AS |
559 | if (failed && (rec->flags & FTRACE_FL_CONVERTED)) { |
560 | rec->flags |= FTRACE_FL_FAILED; | |
561 | if ((system_state == SYSTEM_BOOTING) || | |
34078a5e | 562 | !core_kernel_text(rec->ip)) { |
0eb96701 | 563 | ftrace_free_rec(rec); |
b17e8a37 | 564 | } else |
31e88909 | 565 | ftrace_bug(failed, rec->ip); |
0eb96701 | 566 | } |
3c1720f0 SR |
567 | } |
568 | } | |
569 | } | |
570 | ||
492a7ea5 | 571 | static int |
31e88909 | 572 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 SR |
573 | { |
574 | unsigned long ip; | |
593eb8a2 | 575 | int ret; |
3c1720f0 SR |
576 | |
577 | ip = rec->ip; | |
578 | ||
31e88909 | 579 | ret = ftrace_make_nop(mod, rec, mcount_addr); |
593eb8a2 | 580 | if (ret) { |
31e88909 | 581 | ftrace_bug(ret, ip); |
3c1720f0 | 582 | rec->flags |= FTRACE_FL_FAILED; |
492a7ea5 | 583 | return 0; |
37ad5084 | 584 | } |
492a7ea5 | 585 | return 1; |
3c1720f0 SR |
586 | } |
587 | ||
e309b41d | 588 | static int __ftrace_modify_code(void *data) |
3d083395 | 589 | { |
d61f82d0 SR |
590 | int *command = data; |
591 | ||
a3583244 | 592 | if (*command & FTRACE_ENABLE_CALLS) |
d61f82d0 | 593 | ftrace_replace_code(1); |
a3583244 | 594 | else if (*command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
595 | ftrace_replace_code(0); |
596 | ||
597 | if (*command & FTRACE_UPDATE_TRACE_FUNC) | |
598 | ftrace_update_ftrace_func(ftrace_trace_function); | |
599 | ||
5a45cfe1 SR |
600 | if (*command & FTRACE_START_FUNC_RET) |
601 | ftrace_enable_ftrace_graph_caller(); | |
602 | else if (*command & FTRACE_STOP_FUNC_RET) | |
603 | ftrace_disable_ftrace_graph_caller(); | |
604 | ||
d61f82d0 | 605 | return 0; |
3d083395 SR |
606 | } |
607 | ||
e309b41d | 608 | static void ftrace_run_update_code(int command) |
3d083395 | 609 | { |
784e2d76 | 610 | stop_machine(__ftrace_modify_code, &command, NULL); |
3d083395 SR |
611 | } |
612 | ||
d61f82d0 | 613 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 614 | static int ftrace_start_up; |
df4fc315 SR |
615 | |
616 | static void ftrace_startup_enable(int command) | |
617 | { | |
618 | if (saved_ftrace_func != ftrace_trace_function) { | |
619 | saved_ftrace_func = ftrace_trace_function; | |
620 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
621 | } | |
622 | ||
623 | if (!command || !ftrace_enabled) | |
624 | return; | |
625 | ||
626 | ftrace_run_update_code(command); | |
627 | } | |
d61f82d0 | 628 | |
5a45cfe1 | 629 | static void ftrace_startup(int command) |
3d083395 | 630 | { |
4eebcc81 SR |
631 | if (unlikely(ftrace_disabled)) |
632 | return; | |
633 | ||
cb7be3b2 | 634 | mutex_lock(&ftrace_start_lock); |
60a7ecf4 | 635 | ftrace_start_up++; |
982c350b | 636 | command |= FTRACE_ENABLE_CALLS; |
d61f82d0 | 637 | |
df4fc315 | 638 | ftrace_startup_enable(command); |
3d083395 | 639 | |
cb7be3b2 | 640 | mutex_unlock(&ftrace_start_lock); |
3d083395 SR |
641 | } |
642 | ||
5a45cfe1 | 643 | static void ftrace_shutdown(int command) |
3d083395 | 644 | { |
4eebcc81 SR |
645 | if (unlikely(ftrace_disabled)) |
646 | return; | |
647 | ||
cb7be3b2 | 648 | mutex_lock(&ftrace_start_lock); |
60a7ecf4 SR |
649 | ftrace_start_up--; |
650 | if (!ftrace_start_up) | |
d61f82d0 | 651 | command |= FTRACE_DISABLE_CALLS; |
3d083395 | 652 | |
d61f82d0 SR |
653 | if (saved_ftrace_func != ftrace_trace_function) { |
654 | saved_ftrace_func = ftrace_trace_function; | |
655 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
656 | } | |
3d083395 | 657 | |
d61f82d0 SR |
658 | if (!command || !ftrace_enabled) |
659 | goto out; | |
660 | ||
661 | ftrace_run_update_code(command); | |
3d083395 | 662 | out: |
cb7be3b2 | 663 | mutex_unlock(&ftrace_start_lock); |
3d083395 SR |
664 | } |
665 | ||
e309b41d | 666 | static void ftrace_startup_sysctl(void) |
b0fc494f | 667 | { |
d61f82d0 SR |
668 | int command = FTRACE_ENABLE_MCOUNT; |
669 | ||
4eebcc81 SR |
670 | if (unlikely(ftrace_disabled)) |
671 | return; | |
672 | ||
cb7be3b2 | 673 | mutex_lock(&ftrace_start_lock); |
d61f82d0 SR |
674 | /* Force update next time */ |
675 | saved_ftrace_func = NULL; | |
60a7ecf4 SR |
676 | /* ftrace_start_up is true if we want ftrace running */ |
677 | if (ftrace_start_up) | |
d61f82d0 SR |
678 | command |= FTRACE_ENABLE_CALLS; |
679 | ||
680 | ftrace_run_update_code(command); | |
cb7be3b2 | 681 | mutex_unlock(&ftrace_start_lock); |
b0fc494f SR |
682 | } |
683 | ||
e309b41d | 684 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 685 | { |
d61f82d0 SR |
686 | int command = FTRACE_DISABLE_MCOUNT; |
687 | ||
4eebcc81 SR |
688 | if (unlikely(ftrace_disabled)) |
689 | return; | |
690 | ||
cb7be3b2 | 691 | mutex_lock(&ftrace_start_lock); |
60a7ecf4 SR |
692 | /* ftrace_start_up is true if ftrace is running */ |
693 | if (ftrace_start_up) | |
d61f82d0 SR |
694 | command |= FTRACE_DISABLE_CALLS; |
695 | ||
696 | ftrace_run_update_code(command); | |
cb7be3b2 | 697 | mutex_unlock(&ftrace_start_lock); |
b0fc494f SR |
698 | } |
699 | ||
3d083395 SR |
700 | static cycle_t ftrace_update_time; |
701 | static unsigned long ftrace_update_cnt; | |
702 | unsigned long ftrace_update_tot_cnt; | |
703 | ||
31e88909 | 704 | static int ftrace_update_code(struct module *mod) |
3d083395 | 705 | { |
08f5ac90 | 706 | struct dyn_ftrace *p, *t; |
f22f9a89 | 707 | cycle_t start, stop; |
3d083395 | 708 | |
750ed1a4 | 709 | start = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
710 | ftrace_update_cnt = 0; |
711 | ||
08f5ac90 | 712 | list_for_each_entry_safe(p, t, &ftrace_new_addrs, list) { |
3d083395 | 713 | |
08f5ac90 SR |
714 | /* If something went wrong, bail without enabling anything */ |
715 | if (unlikely(ftrace_disabled)) | |
716 | return -1; | |
f22f9a89 | 717 | |
08f5ac90 | 718 | list_del_init(&p->list); |
f22f9a89 | 719 | |
08f5ac90 | 720 | /* convert record (i.e, patch mcount-call with NOP) */ |
31e88909 | 721 | if (ftrace_code_disable(mod, p)) { |
08f5ac90 SR |
722 | p->flags |= FTRACE_FL_CONVERTED; |
723 | ftrace_update_cnt++; | |
724 | } else | |
725 | ftrace_free_rec(p); | |
3d083395 SR |
726 | } |
727 | ||
750ed1a4 | 728 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
729 | ftrace_update_time = stop - start; |
730 | ftrace_update_tot_cnt += ftrace_update_cnt; | |
731 | ||
16444a8a ACM |
732 | return 0; |
733 | } | |
734 | ||
68bf21aa | 735 | static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) |
3c1720f0 SR |
736 | { |
737 | struct ftrace_page *pg; | |
738 | int cnt; | |
739 | int i; | |
3c1720f0 SR |
740 | |
741 | /* allocate a few pages */ | |
742 | ftrace_pages_start = (void *)get_zeroed_page(GFP_KERNEL); | |
743 | if (!ftrace_pages_start) | |
744 | return -1; | |
745 | ||
746 | /* | |
747 | * Allocate a few more pages. | |
748 | * | |
749 | * TODO: have some parser search vmlinux before | |
750 | * final linking to find all calls to ftrace. | |
751 | * Then we can: | |
752 | * a) know how many pages to allocate. | |
753 | * and/or | |
754 | * b) set up the table then. | |
755 | * | |
756 | * The dynamic code is still necessary for | |
757 | * modules. | |
758 | */ | |
759 | ||
760 | pg = ftrace_pages = ftrace_pages_start; | |
761 | ||
68bf21aa | 762 | cnt = num_to_init / ENTRIES_PER_PAGE; |
08f5ac90 | 763 | pr_info("ftrace: allocating %ld entries in %d pages\n", |
5821e1b7 | 764 | num_to_init, cnt + 1); |
3c1720f0 SR |
765 | |
766 | for (i = 0; i < cnt; i++) { | |
767 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); | |
768 | ||
769 | /* If we fail, we'll try later anyway */ | |
770 | if (!pg->next) | |
771 | break; | |
772 | ||
773 | pg = pg->next; | |
774 | } | |
775 | ||
776 | return 0; | |
777 | } | |
778 | ||
5072c59f SR |
779 | enum { |
780 | FTRACE_ITER_FILTER = (1 << 0), | |
781 | FTRACE_ITER_CONT = (1 << 1), | |
41c52c0d | 782 | FTRACE_ITER_NOTRACE = (1 << 2), |
eb9a7bf0 | 783 | FTRACE_ITER_FAILURES = (1 << 3), |
5072c59f SR |
784 | }; |
785 | ||
786 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ | |
787 | ||
788 | struct ftrace_iterator { | |
5072c59f SR |
789 | struct ftrace_page *pg; |
790 | unsigned idx; | |
791 | unsigned flags; | |
792 | unsigned char buffer[FTRACE_BUFF_MAX+1]; | |
793 | unsigned buffer_idx; | |
794 | unsigned filtered; | |
795 | }; | |
796 | ||
e309b41d | 797 | static void * |
5072c59f SR |
798 | t_next(struct seq_file *m, void *v, loff_t *pos) |
799 | { | |
800 | struct ftrace_iterator *iter = m->private; | |
801 | struct dyn_ftrace *rec = NULL; | |
802 | ||
803 | (*pos)++; | |
804 | ||
99ecdc43 SR |
805 | /* should not be called from interrupt context */ |
806 | spin_lock(&ftrace_lock); | |
5072c59f SR |
807 | retry: |
808 | if (iter->idx >= iter->pg->index) { | |
809 | if (iter->pg->next) { | |
810 | iter->pg = iter->pg->next; | |
811 | iter->idx = 0; | |
812 | goto retry; | |
50cdaf08 LW |
813 | } else { |
814 | iter->idx = -1; | |
5072c59f SR |
815 | } |
816 | } else { | |
817 | rec = &iter->pg->records[iter->idx++]; | |
a9fdda33 SR |
818 | if ((rec->flags & FTRACE_FL_FREE) || |
819 | ||
820 | (!(iter->flags & FTRACE_ITER_FAILURES) && | |
eb9a7bf0 AS |
821 | (rec->flags & FTRACE_FL_FAILED)) || |
822 | ||
823 | ((iter->flags & FTRACE_ITER_FAILURES) && | |
a9fdda33 | 824 | !(rec->flags & FTRACE_FL_FAILED)) || |
eb9a7bf0 | 825 | |
0183fb1c SR |
826 | ((iter->flags & FTRACE_ITER_FILTER) && |
827 | !(rec->flags & FTRACE_FL_FILTER)) || | |
828 | ||
41c52c0d SR |
829 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
830 | !(rec->flags & FTRACE_FL_NOTRACE))) { | |
5072c59f SR |
831 | rec = NULL; |
832 | goto retry; | |
833 | } | |
834 | } | |
99ecdc43 | 835 | spin_unlock(&ftrace_lock); |
5072c59f | 836 | |
5072c59f SR |
837 | return rec; |
838 | } | |
839 | ||
840 | static void *t_start(struct seq_file *m, loff_t *pos) | |
841 | { | |
842 | struct ftrace_iterator *iter = m->private; | |
843 | void *p = NULL; | |
5072c59f | 844 | |
50cdaf08 LW |
845 | if (*pos > 0) { |
846 | if (iter->idx < 0) | |
847 | return p; | |
848 | (*pos)--; | |
849 | iter->idx--; | |
850 | } | |
5821e1b7 | 851 | |
50cdaf08 | 852 | p = t_next(m, p, pos); |
5072c59f SR |
853 | |
854 | return p; | |
855 | } | |
856 | ||
857 | static void t_stop(struct seq_file *m, void *p) | |
858 | { | |
859 | } | |
860 | ||
861 | static int t_show(struct seq_file *m, void *v) | |
862 | { | |
863 | struct dyn_ftrace *rec = v; | |
864 | char str[KSYM_SYMBOL_LEN]; | |
865 | ||
866 | if (!rec) | |
867 | return 0; | |
868 | ||
869 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
870 | ||
50cdaf08 | 871 | seq_printf(m, "%s\n", str); |
5072c59f SR |
872 | |
873 | return 0; | |
874 | } | |
875 | ||
876 | static struct seq_operations show_ftrace_seq_ops = { | |
877 | .start = t_start, | |
878 | .next = t_next, | |
879 | .stop = t_stop, | |
880 | .show = t_show, | |
881 | }; | |
882 | ||
e309b41d | 883 | static int |
5072c59f SR |
884 | ftrace_avail_open(struct inode *inode, struct file *file) |
885 | { | |
886 | struct ftrace_iterator *iter; | |
887 | int ret; | |
888 | ||
4eebcc81 SR |
889 | if (unlikely(ftrace_disabled)) |
890 | return -ENODEV; | |
891 | ||
5072c59f SR |
892 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
893 | if (!iter) | |
894 | return -ENOMEM; | |
895 | ||
896 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
897 | |
898 | ret = seq_open(file, &show_ftrace_seq_ops); | |
899 | if (!ret) { | |
900 | struct seq_file *m = file->private_data; | |
4bf39a94 | 901 | |
5072c59f | 902 | m->private = iter; |
4bf39a94 | 903 | } else { |
5072c59f | 904 | kfree(iter); |
4bf39a94 | 905 | } |
5072c59f SR |
906 | |
907 | return ret; | |
908 | } | |
909 | ||
910 | int ftrace_avail_release(struct inode *inode, struct file *file) | |
911 | { | |
912 | struct seq_file *m = (struct seq_file *)file->private_data; | |
913 | struct ftrace_iterator *iter = m->private; | |
914 | ||
915 | seq_release(inode, file); | |
916 | kfree(iter); | |
4bf39a94 | 917 | |
5072c59f SR |
918 | return 0; |
919 | } | |
920 | ||
eb9a7bf0 AS |
921 | static int |
922 | ftrace_failures_open(struct inode *inode, struct file *file) | |
923 | { | |
924 | int ret; | |
925 | struct seq_file *m; | |
926 | struct ftrace_iterator *iter; | |
927 | ||
928 | ret = ftrace_avail_open(inode, file); | |
929 | if (!ret) { | |
930 | m = (struct seq_file *)file->private_data; | |
931 | iter = (struct ftrace_iterator *)m->private; | |
932 | iter->flags = FTRACE_ITER_FAILURES; | |
933 | } | |
934 | ||
935 | return ret; | |
936 | } | |
937 | ||
938 | ||
41c52c0d | 939 | static void ftrace_filter_reset(int enable) |
5072c59f SR |
940 | { |
941 | struct ftrace_page *pg; | |
942 | struct dyn_ftrace *rec; | |
41c52c0d | 943 | unsigned long type = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
5072c59f SR |
944 | unsigned i; |
945 | ||
99ecdc43 SR |
946 | /* should not be called from interrupt context */ |
947 | spin_lock(&ftrace_lock); | |
41c52c0d SR |
948 | if (enable) |
949 | ftrace_filtered = 0; | |
5072c59f SR |
950 | pg = ftrace_pages_start; |
951 | while (pg) { | |
952 | for (i = 0; i < pg->index; i++) { | |
953 | rec = &pg->records[i]; | |
954 | if (rec->flags & FTRACE_FL_FAILED) | |
955 | continue; | |
41c52c0d | 956 | rec->flags &= ~type; |
5072c59f SR |
957 | } |
958 | pg = pg->next; | |
959 | } | |
99ecdc43 | 960 | spin_unlock(&ftrace_lock); |
5072c59f SR |
961 | } |
962 | ||
e309b41d | 963 | static int |
41c52c0d | 964 | ftrace_regex_open(struct inode *inode, struct file *file, int enable) |
5072c59f SR |
965 | { |
966 | struct ftrace_iterator *iter; | |
967 | int ret = 0; | |
968 | ||
4eebcc81 SR |
969 | if (unlikely(ftrace_disabled)) |
970 | return -ENODEV; | |
971 | ||
5072c59f SR |
972 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
973 | if (!iter) | |
974 | return -ENOMEM; | |
975 | ||
41c52c0d | 976 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
977 | if ((file->f_mode & FMODE_WRITE) && |
978 | !(file->f_flags & O_APPEND)) | |
41c52c0d | 979 | ftrace_filter_reset(enable); |
5072c59f SR |
980 | |
981 | if (file->f_mode & FMODE_READ) { | |
982 | iter->pg = ftrace_pages_start; | |
41c52c0d SR |
983 | iter->flags = enable ? FTRACE_ITER_FILTER : |
984 | FTRACE_ITER_NOTRACE; | |
5072c59f SR |
985 | |
986 | ret = seq_open(file, &show_ftrace_seq_ops); | |
987 | if (!ret) { | |
988 | struct seq_file *m = file->private_data; | |
989 | m->private = iter; | |
990 | } else | |
991 | kfree(iter); | |
992 | } else | |
993 | file->private_data = iter; | |
41c52c0d | 994 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
995 | |
996 | return ret; | |
997 | } | |
998 | ||
41c52c0d SR |
999 | static int |
1000 | ftrace_filter_open(struct inode *inode, struct file *file) | |
1001 | { | |
1002 | return ftrace_regex_open(inode, file, 1); | |
1003 | } | |
1004 | ||
1005 | static int | |
1006 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
1007 | { | |
1008 | return ftrace_regex_open(inode, file, 0); | |
1009 | } | |
1010 | ||
e309b41d | 1011 | static ssize_t |
41c52c0d | 1012 | ftrace_regex_read(struct file *file, char __user *ubuf, |
5072c59f SR |
1013 | size_t cnt, loff_t *ppos) |
1014 | { | |
1015 | if (file->f_mode & FMODE_READ) | |
1016 | return seq_read(file, ubuf, cnt, ppos); | |
1017 | else | |
1018 | return -EPERM; | |
1019 | } | |
1020 | ||
e309b41d | 1021 | static loff_t |
41c52c0d | 1022 | ftrace_regex_lseek(struct file *file, loff_t offset, int origin) |
5072c59f SR |
1023 | { |
1024 | loff_t ret; | |
1025 | ||
1026 | if (file->f_mode & FMODE_READ) | |
1027 | ret = seq_lseek(file, offset, origin); | |
1028 | else | |
1029 | file->f_pos = ret = 1; | |
1030 | ||
1031 | return ret; | |
1032 | } | |
1033 | ||
1034 | enum { | |
1035 | MATCH_FULL, | |
1036 | MATCH_FRONT_ONLY, | |
1037 | MATCH_MIDDLE_ONLY, | |
1038 | MATCH_END_ONLY, | |
1039 | }; | |
1040 | ||
e309b41d | 1041 | static void |
41c52c0d | 1042 | ftrace_match(unsigned char *buff, int len, int enable) |
5072c59f SR |
1043 | { |
1044 | char str[KSYM_SYMBOL_LEN]; | |
1045 | char *search = NULL; | |
1046 | struct ftrace_page *pg; | |
1047 | struct dyn_ftrace *rec; | |
1048 | int type = MATCH_FULL; | |
41c52c0d | 1049 | unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
5072c59f | 1050 | unsigned i, match = 0, search_len = 0; |
ea3a6d6d SR |
1051 | int not = 0; |
1052 | ||
1053 | if (buff[0] == '!') { | |
1054 | not = 1; | |
1055 | buff++; | |
1056 | len--; | |
1057 | } | |
5072c59f SR |
1058 | |
1059 | for (i = 0; i < len; i++) { | |
1060 | if (buff[i] == '*') { | |
1061 | if (!i) { | |
1062 | search = buff + i + 1; | |
1063 | type = MATCH_END_ONLY; | |
1064 | search_len = len - (i + 1); | |
1065 | } else { | |
1066 | if (type == MATCH_END_ONLY) { | |
1067 | type = MATCH_MIDDLE_ONLY; | |
1068 | } else { | |
1069 | match = i; | |
1070 | type = MATCH_FRONT_ONLY; | |
1071 | } | |
1072 | buff[i] = 0; | |
1073 | break; | |
1074 | } | |
1075 | } | |
1076 | } | |
1077 | ||
99ecdc43 SR |
1078 | /* should not be called from interrupt context */ |
1079 | spin_lock(&ftrace_lock); | |
41c52c0d SR |
1080 | if (enable) |
1081 | ftrace_filtered = 1; | |
5072c59f SR |
1082 | pg = ftrace_pages_start; |
1083 | while (pg) { | |
1084 | for (i = 0; i < pg->index; i++) { | |
1085 | int matched = 0; | |
1086 | char *ptr; | |
1087 | ||
1088 | rec = &pg->records[i]; | |
1089 | if (rec->flags & FTRACE_FL_FAILED) | |
1090 | continue; | |
1091 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
1092 | switch (type) { | |
1093 | case MATCH_FULL: | |
1094 | if (strcmp(str, buff) == 0) | |
1095 | matched = 1; | |
1096 | break; | |
1097 | case MATCH_FRONT_ONLY: | |
1098 | if (memcmp(str, buff, match) == 0) | |
1099 | matched = 1; | |
1100 | break; | |
1101 | case MATCH_MIDDLE_ONLY: | |
1102 | if (strstr(str, search)) | |
1103 | matched = 1; | |
1104 | break; | |
1105 | case MATCH_END_ONLY: | |
1106 | ptr = strstr(str, search); | |
1107 | if (ptr && (ptr[search_len] == 0)) | |
1108 | matched = 1; | |
1109 | break; | |
1110 | } | |
ea3a6d6d SR |
1111 | if (matched) { |
1112 | if (not) | |
1113 | rec->flags &= ~flag; | |
1114 | else | |
1115 | rec->flags |= flag; | |
1116 | } | |
5072c59f SR |
1117 | } |
1118 | pg = pg->next; | |
1119 | } | |
99ecdc43 | 1120 | spin_unlock(&ftrace_lock); |
5072c59f SR |
1121 | } |
1122 | ||
e309b41d | 1123 | static ssize_t |
41c52c0d SR |
1124 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
1125 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
1126 | { |
1127 | struct ftrace_iterator *iter; | |
1128 | char ch; | |
1129 | size_t read = 0; | |
1130 | ssize_t ret; | |
1131 | ||
1132 | if (!cnt || cnt < 0) | |
1133 | return 0; | |
1134 | ||
41c52c0d | 1135 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
1136 | |
1137 | if (file->f_mode & FMODE_READ) { | |
1138 | struct seq_file *m = file->private_data; | |
1139 | iter = m->private; | |
1140 | } else | |
1141 | iter = file->private_data; | |
1142 | ||
1143 | if (!*ppos) { | |
1144 | iter->flags &= ~FTRACE_ITER_CONT; | |
1145 | iter->buffer_idx = 0; | |
1146 | } | |
1147 | ||
1148 | ret = get_user(ch, ubuf++); | |
1149 | if (ret) | |
1150 | goto out; | |
1151 | read++; | |
1152 | cnt--; | |
1153 | ||
1154 | if (!(iter->flags & ~FTRACE_ITER_CONT)) { | |
1155 | /* skip white space */ | |
1156 | while (cnt && isspace(ch)) { | |
1157 | ret = get_user(ch, ubuf++); | |
1158 | if (ret) | |
1159 | goto out; | |
1160 | read++; | |
1161 | cnt--; | |
1162 | } | |
1163 | ||
5072c59f SR |
1164 | if (isspace(ch)) { |
1165 | file->f_pos += read; | |
1166 | ret = read; | |
1167 | goto out; | |
1168 | } | |
1169 | ||
1170 | iter->buffer_idx = 0; | |
1171 | } | |
1172 | ||
1173 | while (cnt && !isspace(ch)) { | |
1174 | if (iter->buffer_idx < FTRACE_BUFF_MAX) | |
1175 | iter->buffer[iter->buffer_idx++] = ch; | |
1176 | else { | |
1177 | ret = -EINVAL; | |
1178 | goto out; | |
1179 | } | |
1180 | ret = get_user(ch, ubuf++); | |
1181 | if (ret) | |
1182 | goto out; | |
1183 | read++; | |
1184 | cnt--; | |
1185 | } | |
1186 | ||
1187 | if (isspace(ch)) { | |
1188 | iter->filtered++; | |
1189 | iter->buffer[iter->buffer_idx] = 0; | |
41c52c0d | 1190 | ftrace_match(iter->buffer, iter->buffer_idx, enable); |
5072c59f SR |
1191 | iter->buffer_idx = 0; |
1192 | } else | |
1193 | iter->flags |= FTRACE_ITER_CONT; | |
1194 | ||
1195 | ||
1196 | file->f_pos += read; | |
1197 | ||
1198 | ret = read; | |
1199 | out: | |
41c52c0d | 1200 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
1201 | |
1202 | return ret; | |
1203 | } | |
1204 | ||
41c52c0d SR |
1205 | static ssize_t |
1206 | ftrace_filter_write(struct file *file, const char __user *ubuf, | |
1207 | size_t cnt, loff_t *ppos) | |
1208 | { | |
1209 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
1210 | } | |
1211 | ||
1212 | static ssize_t | |
1213 | ftrace_notrace_write(struct file *file, const char __user *ubuf, | |
1214 | size_t cnt, loff_t *ppos) | |
1215 | { | |
1216 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
1217 | } | |
1218 | ||
1219 | static void | |
1220 | ftrace_set_regex(unsigned char *buf, int len, int reset, int enable) | |
1221 | { | |
1222 | if (unlikely(ftrace_disabled)) | |
1223 | return; | |
1224 | ||
1225 | mutex_lock(&ftrace_regex_lock); | |
1226 | if (reset) | |
1227 | ftrace_filter_reset(enable); | |
1228 | if (buf) | |
1229 | ftrace_match(buf, len, enable); | |
1230 | mutex_unlock(&ftrace_regex_lock); | |
1231 | } | |
1232 | ||
77a2b37d SR |
1233 | /** |
1234 | * ftrace_set_filter - set a function to filter on in ftrace | |
1235 | * @buf - the string that holds the function filter text. | |
1236 | * @len - the length of the string. | |
1237 | * @reset - non zero to reset all filters before applying this filter. | |
1238 | * | |
1239 | * Filters denote which functions should be enabled when tracing is enabled. | |
1240 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
1241 | */ | |
e309b41d | 1242 | void ftrace_set_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 1243 | { |
41c52c0d SR |
1244 | ftrace_set_regex(buf, len, reset, 1); |
1245 | } | |
4eebcc81 | 1246 | |
41c52c0d SR |
1247 | /** |
1248 | * ftrace_set_notrace - set a function to not trace in ftrace | |
1249 | * @buf - the string that holds the function notrace text. | |
1250 | * @len - the length of the string. | |
1251 | * @reset - non zero to reset all filters before applying this filter. | |
1252 | * | |
1253 | * Notrace Filters denote which functions should not be enabled when tracing | |
1254 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
1255 | * for tracing. | |
1256 | */ | |
1257 | void ftrace_set_notrace(unsigned char *buf, int len, int reset) | |
1258 | { | |
1259 | ftrace_set_regex(buf, len, reset, 0); | |
77a2b37d SR |
1260 | } |
1261 | ||
e309b41d | 1262 | static int |
41c52c0d | 1263 | ftrace_regex_release(struct inode *inode, struct file *file, int enable) |
5072c59f SR |
1264 | { |
1265 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1266 | struct ftrace_iterator *iter; | |
1267 | ||
41c52c0d | 1268 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
1269 | if (file->f_mode & FMODE_READ) { |
1270 | iter = m->private; | |
1271 | ||
1272 | seq_release(inode, file); | |
1273 | } else | |
1274 | iter = file->private_data; | |
1275 | ||
1276 | if (iter->buffer_idx) { | |
1277 | iter->filtered++; | |
1278 | iter->buffer[iter->buffer_idx] = 0; | |
41c52c0d | 1279 | ftrace_match(iter->buffer, iter->buffer_idx, enable); |
5072c59f SR |
1280 | } |
1281 | ||
1282 | mutex_lock(&ftrace_sysctl_lock); | |
cb7be3b2 | 1283 | mutex_lock(&ftrace_start_lock); |
ee02a2e5 | 1284 | if (ftrace_start_up && ftrace_enabled) |
5072c59f | 1285 | ftrace_run_update_code(FTRACE_ENABLE_CALLS); |
cb7be3b2 | 1286 | mutex_unlock(&ftrace_start_lock); |
5072c59f SR |
1287 | mutex_unlock(&ftrace_sysctl_lock); |
1288 | ||
1289 | kfree(iter); | |
41c52c0d | 1290 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
1291 | return 0; |
1292 | } | |
1293 | ||
41c52c0d SR |
1294 | static int |
1295 | ftrace_filter_release(struct inode *inode, struct file *file) | |
1296 | { | |
1297 | return ftrace_regex_release(inode, file, 1); | |
1298 | } | |
1299 | ||
1300 | static int | |
1301 | ftrace_notrace_release(struct inode *inode, struct file *file) | |
1302 | { | |
1303 | return ftrace_regex_release(inode, file, 0); | |
1304 | } | |
1305 | ||
5072c59f SR |
1306 | static struct file_operations ftrace_avail_fops = { |
1307 | .open = ftrace_avail_open, | |
1308 | .read = seq_read, | |
1309 | .llseek = seq_lseek, | |
1310 | .release = ftrace_avail_release, | |
1311 | }; | |
1312 | ||
eb9a7bf0 AS |
1313 | static struct file_operations ftrace_failures_fops = { |
1314 | .open = ftrace_failures_open, | |
1315 | .read = seq_read, | |
1316 | .llseek = seq_lseek, | |
1317 | .release = ftrace_avail_release, | |
1318 | }; | |
1319 | ||
5072c59f SR |
1320 | static struct file_operations ftrace_filter_fops = { |
1321 | .open = ftrace_filter_open, | |
41c52c0d | 1322 | .read = ftrace_regex_read, |
5072c59f | 1323 | .write = ftrace_filter_write, |
41c52c0d | 1324 | .llseek = ftrace_regex_lseek, |
5072c59f SR |
1325 | .release = ftrace_filter_release, |
1326 | }; | |
1327 | ||
41c52c0d SR |
1328 | static struct file_operations ftrace_notrace_fops = { |
1329 | .open = ftrace_notrace_open, | |
1330 | .read = ftrace_regex_read, | |
1331 | .write = ftrace_notrace_write, | |
1332 | .llseek = ftrace_regex_lseek, | |
1333 | .release = ftrace_notrace_release, | |
1334 | }; | |
1335 | ||
ea4e2bc4 SR |
1336 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
1337 | ||
1338 | static DEFINE_MUTEX(graph_lock); | |
1339 | ||
1340 | int ftrace_graph_count; | |
1341 | unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; | |
1342 | ||
1343 | static void * | |
1344 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
1345 | { | |
1346 | unsigned long *array = m->private; | |
1347 | int index = *pos; | |
1348 | ||
1349 | (*pos)++; | |
1350 | ||
1351 | if (index >= ftrace_graph_count) | |
1352 | return NULL; | |
1353 | ||
1354 | return &array[index]; | |
1355 | } | |
1356 | ||
1357 | static void *g_start(struct seq_file *m, loff_t *pos) | |
1358 | { | |
1359 | void *p = NULL; | |
1360 | ||
1361 | mutex_lock(&graph_lock); | |
1362 | ||
1363 | p = g_next(m, p, pos); | |
1364 | ||
1365 | return p; | |
1366 | } | |
1367 | ||
1368 | static void g_stop(struct seq_file *m, void *p) | |
1369 | { | |
1370 | mutex_unlock(&graph_lock); | |
1371 | } | |
1372 | ||
1373 | static int g_show(struct seq_file *m, void *v) | |
1374 | { | |
1375 | unsigned long *ptr = v; | |
1376 | char str[KSYM_SYMBOL_LEN]; | |
1377 | ||
1378 | if (!ptr) | |
1379 | return 0; | |
1380 | ||
1381 | kallsyms_lookup(*ptr, NULL, NULL, NULL, str); | |
1382 | ||
1383 | seq_printf(m, "%s\n", str); | |
1384 | ||
1385 | return 0; | |
1386 | } | |
1387 | ||
1388 | static struct seq_operations ftrace_graph_seq_ops = { | |
1389 | .start = g_start, | |
1390 | .next = g_next, | |
1391 | .stop = g_stop, | |
1392 | .show = g_show, | |
1393 | }; | |
1394 | ||
1395 | static int | |
1396 | ftrace_graph_open(struct inode *inode, struct file *file) | |
1397 | { | |
1398 | int ret = 0; | |
1399 | ||
1400 | if (unlikely(ftrace_disabled)) | |
1401 | return -ENODEV; | |
1402 | ||
1403 | mutex_lock(&graph_lock); | |
1404 | if ((file->f_mode & FMODE_WRITE) && | |
1405 | !(file->f_flags & O_APPEND)) { | |
1406 | ftrace_graph_count = 0; | |
1407 | memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); | |
1408 | } | |
1409 | ||
1410 | if (file->f_mode & FMODE_READ) { | |
1411 | ret = seq_open(file, &ftrace_graph_seq_ops); | |
1412 | if (!ret) { | |
1413 | struct seq_file *m = file->private_data; | |
1414 | m->private = ftrace_graph_funcs; | |
1415 | } | |
1416 | } else | |
1417 | file->private_data = ftrace_graph_funcs; | |
1418 | mutex_unlock(&graph_lock); | |
1419 | ||
1420 | return ret; | |
1421 | } | |
1422 | ||
1423 | static ssize_t | |
1424 | ftrace_graph_read(struct file *file, char __user *ubuf, | |
1425 | size_t cnt, loff_t *ppos) | |
1426 | { | |
1427 | if (file->f_mode & FMODE_READ) | |
1428 | return seq_read(file, ubuf, cnt, ppos); | |
1429 | else | |
1430 | return -EPERM; | |
1431 | } | |
1432 | ||
1433 | static int | |
1434 | ftrace_set_func(unsigned long *array, int idx, char *buffer) | |
1435 | { | |
1436 | char str[KSYM_SYMBOL_LEN]; | |
1437 | struct dyn_ftrace *rec; | |
1438 | struct ftrace_page *pg; | |
1439 | int found = 0; | |
faec2ec5 | 1440 | int i, j; |
ea4e2bc4 SR |
1441 | |
1442 | if (ftrace_disabled) | |
1443 | return -ENODEV; | |
1444 | ||
1445 | /* should not be called from interrupt context */ | |
1446 | spin_lock(&ftrace_lock); | |
1447 | ||
1448 | for (pg = ftrace_pages_start; pg; pg = pg->next) { | |
1449 | for (i = 0; i < pg->index; i++) { | |
1450 | rec = &pg->records[i]; | |
1451 | ||
1452 | if (rec->flags & (FTRACE_FL_FAILED | FTRACE_FL_FREE)) | |
1453 | continue; | |
1454 | ||
1455 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
1456 | if (strcmp(str, buffer) == 0) { | |
1457 | found = 1; | |
faec2ec5 LW |
1458 | for (j = 0; j < idx; j++) |
1459 | if (array[j] == rec->ip) { | |
1460 | found = 0; | |
1461 | break; | |
1462 | } | |
1463 | if (found) | |
1464 | array[idx] = rec->ip; | |
ea4e2bc4 SR |
1465 | break; |
1466 | } | |
1467 | } | |
1468 | } | |
1469 | spin_unlock(&ftrace_lock); | |
1470 | ||
1471 | return found ? 0 : -EINVAL; | |
1472 | } | |
1473 | ||
1474 | static ssize_t | |
1475 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
1476 | size_t cnt, loff_t *ppos) | |
1477 | { | |
1478 | unsigned char buffer[FTRACE_BUFF_MAX+1]; | |
1479 | unsigned long *array; | |
1480 | size_t read = 0; | |
1481 | ssize_t ret; | |
1482 | int index = 0; | |
1483 | char ch; | |
1484 | ||
1485 | if (!cnt || cnt < 0) | |
1486 | return 0; | |
1487 | ||
1488 | mutex_lock(&graph_lock); | |
1489 | ||
1490 | if (ftrace_graph_count >= FTRACE_GRAPH_MAX_FUNCS) { | |
1491 | ret = -EBUSY; | |
1492 | goto out; | |
1493 | } | |
1494 | ||
1495 | if (file->f_mode & FMODE_READ) { | |
1496 | struct seq_file *m = file->private_data; | |
1497 | array = m->private; | |
1498 | } else | |
1499 | array = file->private_data; | |
1500 | ||
1501 | ret = get_user(ch, ubuf++); | |
1502 | if (ret) | |
1503 | goto out; | |
1504 | read++; | |
1505 | cnt--; | |
1506 | ||
1507 | /* skip white space */ | |
1508 | while (cnt && isspace(ch)) { | |
1509 | ret = get_user(ch, ubuf++); | |
1510 | if (ret) | |
1511 | goto out; | |
1512 | read++; | |
1513 | cnt--; | |
1514 | } | |
1515 | ||
1516 | if (isspace(ch)) { | |
1517 | *ppos += read; | |
1518 | ret = read; | |
1519 | goto out; | |
1520 | } | |
1521 | ||
1522 | while (cnt && !isspace(ch)) { | |
1523 | if (index < FTRACE_BUFF_MAX) | |
1524 | buffer[index++] = ch; | |
1525 | else { | |
1526 | ret = -EINVAL; | |
1527 | goto out; | |
1528 | } | |
1529 | ret = get_user(ch, ubuf++); | |
1530 | if (ret) | |
1531 | goto out; | |
1532 | read++; | |
1533 | cnt--; | |
1534 | } | |
1535 | buffer[index] = 0; | |
1536 | ||
1537 | /* we allow only one at a time */ | |
1538 | ret = ftrace_set_func(array, ftrace_graph_count, buffer); | |
1539 | if (ret) | |
1540 | goto out; | |
1541 | ||
1542 | ftrace_graph_count++; | |
1543 | ||
1544 | file->f_pos += read; | |
1545 | ||
1546 | ret = read; | |
1547 | out: | |
1548 | mutex_unlock(&graph_lock); | |
1549 | ||
1550 | return ret; | |
1551 | } | |
1552 | ||
1553 | static const struct file_operations ftrace_graph_fops = { | |
1554 | .open = ftrace_graph_open, | |
1555 | .read = ftrace_graph_read, | |
1556 | .write = ftrace_graph_write, | |
1557 | }; | |
1558 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
1559 | ||
df4fc315 | 1560 | static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) |
5072c59f | 1561 | { |
5072c59f SR |
1562 | struct dentry *entry; |
1563 | ||
5072c59f SR |
1564 | entry = debugfs_create_file("available_filter_functions", 0444, |
1565 | d_tracer, NULL, &ftrace_avail_fops); | |
1566 | if (!entry) | |
1567 | pr_warning("Could not create debugfs " | |
1568 | "'available_filter_functions' entry\n"); | |
1569 | ||
eb9a7bf0 AS |
1570 | entry = debugfs_create_file("failures", 0444, |
1571 | d_tracer, NULL, &ftrace_failures_fops); | |
1572 | if (!entry) | |
1573 | pr_warning("Could not create debugfs 'failures' entry\n"); | |
1574 | ||
5072c59f SR |
1575 | entry = debugfs_create_file("set_ftrace_filter", 0644, d_tracer, |
1576 | NULL, &ftrace_filter_fops); | |
1577 | if (!entry) | |
1578 | pr_warning("Could not create debugfs " | |
1579 | "'set_ftrace_filter' entry\n"); | |
41c52c0d SR |
1580 | |
1581 | entry = debugfs_create_file("set_ftrace_notrace", 0644, d_tracer, | |
1582 | NULL, &ftrace_notrace_fops); | |
1583 | if (!entry) | |
1584 | pr_warning("Could not create debugfs " | |
1585 | "'set_ftrace_notrace' entry\n"); | |
ad90c0e3 | 1586 | |
ea4e2bc4 SR |
1587 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
1588 | entry = debugfs_create_file("set_graph_function", 0444, d_tracer, | |
1589 | NULL, | |
1590 | &ftrace_graph_fops); | |
1591 | if (!entry) | |
1592 | pr_warning("Could not create debugfs " | |
1593 | "'set_graph_function' entry\n"); | |
1594 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
1595 | ||
5072c59f SR |
1596 | return 0; |
1597 | } | |
1598 | ||
31e88909 SR |
1599 | static int ftrace_convert_nops(struct module *mod, |
1600 | unsigned long *start, | |
68bf21aa SR |
1601 | unsigned long *end) |
1602 | { | |
1603 | unsigned long *p; | |
1604 | unsigned long addr; | |
1605 | unsigned long flags; | |
1606 | ||
08f5ac90 | 1607 | mutex_lock(&ftrace_start_lock); |
68bf21aa SR |
1608 | p = start; |
1609 | while (p < end) { | |
1610 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
1611 | /* |
1612 | * Some architecture linkers will pad between | |
1613 | * the different mcount_loc sections of different | |
1614 | * object files to satisfy alignments. | |
1615 | * Skip any NULL pointers. | |
1616 | */ | |
1617 | if (!addr) | |
1618 | continue; | |
68bf21aa | 1619 | ftrace_record_ip(addr); |
68bf21aa SR |
1620 | } |
1621 | ||
08f5ac90 | 1622 | /* disable interrupts to prevent kstop machine */ |
68bf21aa | 1623 | local_irq_save(flags); |
31e88909 | 1624 | ftrace_update_code(mod); |
68bf21aa | 1625 | local_irq_restore(flags); |
08f5ac90 | 1626 | mutex_unlock(&ftrace_start_lock); |
68bf21aa SR |
1627 | |
1628 | return 0; | |
1629 | } | |
1630 | ||
31e88909 SR |
1631 | void ftrace_init_module(struct module *mod, |
1632 | unsigned long *start, unsigned long *end) | |
90d595fe | 1633 | { |
00fd61ae | 1634 | if (ftrace_disabled || start == end) |
fed1939c | 1635 | return; |
31e88909 | 1636 | ftrace_convert_nops(mod, start, end); |
90d595fe SR |
1637 | } |
1638 | ||
68bf21aa SR |
1639 | extern unsigned long __start_mcount_loc[]; |
1640 | extern unsigned long __stop_mcount_loc[]; | |
1641 | ||
1642 | void __init ftrace_init(void) | |
1643 | { | |
1644 | unsigned long count, addr, flags; | |
1645 | int ret; | |
1646 | ||
1647 | /* Keep the ftrace pointer to the stub */ | |
1648 | addr = (unsigned long)ftrace_stub; | |
1649 | ||
1650 | local_irq_save(flags); | |
1651 | ftrace_dyn_arch_init(&addr); | |
1652 | local_irq_restore(flags); | |
1653 | ||
1654 | /* ftrace_dyn_arch_init places the return code in addr */ | |
1655 | if (addr) | |
1656 | goto failed; | |
1657 | ||
1658 | count = __stop_mcount_loc - __start_mcount_loc; | |
1659 | ||
1660 | ret = ftrace_dyn_table_alloc(count); | |
1661 | if (ret) | |
1662 | goto failed; | |
1663 | ||
1664 | last_ftrace_enabled = ftrace_enabled = 1; | |
1665 | ||
31e88909 SR |
1666 | ret = ftrace_convert_nops(NULL, |
1667 | __start_mcount_loc, | |
68bf21aa SR |
1668 | __stop_mcount_loc); |
1669 | ||
1670 | return; | |
1671 | failed: | |
1672 | ftrace_disabled = 1; | |
1673 | } | |
68bf21aa | 1674 | |
3d083395 | 1675 | #else |
0b6e4d56 FW |
1676 | |
1677 | static int __init ftrace_nodyn_init(void) | |
1678 | { | |
1679 | ftrace_enabled = 1; | |
1680 | return 0; | |
1681 | } | |
1682 | device_initcall(ftrace_nodyn_init); | |
1683 | ||
df4fc315 SR |
1684 | static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } |
1685 | static inline void ftrace_startup_enable(int command) { } | |
5a45cfe1 SR |
1686 | /* Keep as macros so we do not need to define the commands */ |
1687 | # define ftrace_startup(command) do { } while (0) | |
1688 | # define ftrace_shutdown(command) do { } while (0) | |
c7aafc54 IM |
1689 | # define ftrace_startup_sysctl() do { } while (0) |
1690 | # define ftrace_shutdown_sysctl() do { } while (0) | |
3d083395 SR |
1691 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
1692 | ||
df4fc315 SR |
1693 | static ssize_t |
1694 | ftrace_pid_read(struct file *file, char __user *ubuf, | |
1695 | size_t cnt, loff_t *ppos) | |
1696 | { | |
1697 | char buf[64]; | |
1698 | int r; | |
1699 | ||
e32d8956 SR |
1700 | if (ftrace_pid_trace == ftrace_swapper_pid) |
1701 | r = sprintf(buf, "swapper tasks\n"); | |
1702 | else if (ftrace_pid_trace) | |
978f3a45 | 1703 | r = sprintf(buf, "%u\n", pid_nr(ftrace_pid_trace)); |
df4fc315 SR |
1704 | else |
1705 | r = sprintf(buf, "no pid\n"); | |
1706 | ||
1707 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
1708 | } | |
1709 | ||
e32d8956 | 1710 | static void clear_ftrace_swapper(void) |
978f3a45 SR |
1711 | { |
1712 | struct task_struct *p; | |
e32d8956 | 1713 | int cpu; |
978f3a45 | 1714 | |
e32d8956 SR |
1715 | get_online_cpus(); |
1716 | for_each_online_cpu(cpu) { | |
1717 | p = idle_task(cpu); | |
978f3a45 | 1718 | clear_tsk_trace_trace(p); |
e32d8956 SR |
1719 | } |
1720 | put_online_cpus(); | |
1721 | } | |
978f3a45 | 1722 | |
e32d8956 SR |
1723 | static void set_ftrace_swapper(void) |
1724 | { | |
1725 | struct task_struct *p; | |
1726 | int cpu; | |
1727 | ||
1728 | get_online_cpus(); | |
1729 | for_each_online_cpu(cpu) { | |
1730 | p = idle_task(cpu); | |
1731 | set_tsk_trace_trace(p); | |
1732 | } | |
1733 | put_online_cpus(); | |
978f3a45 SR |
1734 | } |
1735 | ||
e32d8956 SR |
1736 | static void clear_ftrace_pid(struct pid *pid) |
1737 | { | |
1738 | struct task_struct *p; | |
1739 | ||
229c4ef8 | 1740 | rcu_read_lock(); |
e32d8956 SR |
1741 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
1742 | clear_tsk_trace_trace(p); | |
1743 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 ON |
1744 | rcu_read_unlock(); |
1745 | ||
e32d8956 SR |
1746 | put_pid(pid); |
1747 | } | |
1748 | ||
1749 | static void set_ftrace_pid(struct pid *pid) | |
978f3a45 SR |
1750 | { |
1751 | struct task_struct *p; | |
1752 | ||
229c4ef8 | 1753 | rcu_read_lock(); |
978f3a45 SR |
1754 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
1755 | set_tsk_trace_trace(p); | |
1756 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 | 1757 | rcu_read_unlock(); |
978f3a45 SR |
1758 | } |
1759 | ||
e32d8956 SR |
1760 | static void clear_ftrace_pid_task(struct pid **pid) |
1761 | { | |
1762 | if (*pid == ftrace_swapper_pid) | |
1763 | clear_ftrace_swapper(); | |
1764 | else | |
1765 | clear_ftrace_pid(*pid); | |
1766 | ||
1767 | *pid = NULL; | |
1768 | } | |
1769 | ||
1770 | static void set_ftrace_pid_task(struct pid *pid) | |
1771 | { | |
1772 | if (pid == ftrace_swapper_pid) | |
1773 | set_ftrace_swapper(); | |
1774 | else | |
1775 | set_ftrace_pid(pid); | |
1776 | } | |
1777 | ||
df4fc315 SR |
1778 | static ssize_t |
1779 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
1780 | size_t cnt, loff_t *ppos) | |
1781 | { | |
978f3a45 | 1782 | struct pid *pid; |
df4fc315 SR |
1783 | char buf[64]; |
1784 | long val; | |
1785 | int ret; | |
1786 | ||
1787 | if (cnt >= sizeof(buf)) | |
1788 | return -EINVAL; | |
1789 | ||
1790 | if (copy_from_user(&buf, ubuf, cnt)) | |
1791 | return -EFAULT; | |
1792 | ||
1793 | buf[cnt] = 0; | |
1794 | ||
1795 | ret = strict_strtol(buf, 10, &val); | |
1796 | if (ret < 0) | |
1797 | return ret; | |
1798 | ||
1799 | mutex_lock(&ftrace_start_lock); | |
978f3a45 | 1800 | if (val < 0) { |
df4fc315 | 1801 | /* disable pid tracing */ |
978f3a45 | 1802 | if (!ftrace_pid_trace) |
df4fc315 | 1803 | goto out; |
978f3a45 SR |
1804 | |
1805 | clear_ftrace_pid_task(&ftrace_pid_trace); | |
df4fc315 SR |
1806 | |
1807 | } else { | |
e32d8956 SR |
1808 | /* swapper task is special */ |
1809 | if (!val) { | |
1810 | pid = ftrace_swapper_pid; | |
1811 | if (pid == ftrace_pid_trace) | |
1812 | goto out; | |
1813 | } else { | |
1814 | pid = find_get_pid(val); | |
df4fc315 | 1815 | |
e32d8956 SR |
1816 | if (pid == ftrace_pid_trace) { |
1817 | put_pid(pid); | |
1818 | goto out; | |
1819 | } | |
0ef8cde5 | 1820 | } |
0ef8cde5 | 1821 | |
978f3a45 SR |
1822 | if (ftrace_pid_trace) |
1823 | clear_ftrace_pid_task(&ftrace_pid_trace); | |
1824 | ||
1825 | if (!pid) | |
1826 | goto out; | |
1827 | ||
1828 | ftrace_pid_trace = pid; | |
1829 | ||
1830 | set_ftrace_pid_task(ftrace_pid_trace); | |
df4fc315 SR |
1831 | } |
1832 | ||
1833 | /* update the function call */ | |
1834 | ftrace_update_pid_func(); | |
1835 | ftrace_startup_enable(0); | |
1836 | ||
1837 | out: | |
1838 | mutex_unlock(&ftrace_start_lock); | |
1839 | ||
1840 | return cnt; | |
1841 | } | |
1842 | ||
1843 | static struct file_operations ftrace_pid_fops = { | |
1844 | .read = ftrace_pid_read, | |
1845 | .write = ftrace_pid_write, | |
1846 | }; | |
1847 | ||
1848 | static __init int ftrace_init_debugfs(void) | |
1849 | { | |
1850 | struct dentry *d_tracer; | |
1851 | struct dentry *entry; | |
1852 | ||
1853 | d_tracer = tracing_init_dentry(); | |
1854 | if (!d_tracer) | |
1855 | return 0; | |
1856 | ||
1857 | ftrace_init_dyn_debugfs(d_tracer); | |
1858 | ||
1859 | entry = debugfs_create_file("set_ftrace_pid", 0644, d_tracer, | |
1860 | NULL, &ftrace_pid_fops); | |
1861 | if (!entry) | |
1862 | pr_warning("Could not create debugfs " | |
1863 | "'set_ftrace_pid' entry\n"); | |
1864 | return 0; | |
1865 | } | |
1866 | ||
1867 | fs_initcall(ftrace_init_debugfs); | |
1868 | ||
a2bb6a3d | 1869 | /** |
81adbdc0 | 1870 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
1871 | * |
1872 | * This function should be used by panic code. It stops ftrace | |
1873 | * but in a not so nice way. If you need to simply kill ftrace | |
1874 | * from a non-atomic section, use ftrace_kill. | |
1875 | */ | |
81adbdc0 | 1876 | void ftrace_kill(void) |
a2bb6a3d SR |
1877 | { |
1878 | ftrace_disabled = 1; | |
1879 | ftrace_enabled = 0; | |
a2bb6a3d SR |
1880 | clear_ftrace_function(); |
1881 | } | |
1882 | ||
16444a8a | 1883 | /** |
3d083395 SR |
1884 | * register_ftrace_function - register a function for profiling |
1885 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 1886 | * |
3d083395 SR |
1887 | * Register a function to be called by all functions in the |
1888 | * kernel. | |
1889 | * | |
1890 | * Note: @ops->func and all the functions it calls must be labeled | |
1891 | * with "notrace", otherwise it will go into a | |
1892 | * recursive loop. | |
16444a8a | 1893 | */ |
3d083395 | 1894 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 1895 | { |
b0fc494f SR |
1896 | int ret; |
1897 | ||
4eebcc81 SR |
1898 | if (unlikely(ftrace_disabled)) |
1899 | return -1; | |
1900 | ||
b0fc494f | 1901 | mutex_lock(&ftrace_sysctl_lock); |
e7d3737e | 1902 | |
b0fc494f | 1903 | ret = __register_ftrace_function(ops); |
5a45cfe1 | 1904 | ftrace_startup(0); |
b0fc494f | 1905 | |
e7d3737e | 1906 | mutex_unlock(&ftrace_sysctl_lock); |
b0fc494f | 1907 | return ret; |
3d083395 SR |
1908 | } |
1909 | ||
1910 | /** | |
1911 | * unregister_ftrace_function - unresgister a function for profiling. | |
1912 | * @ops - ops structure that holds the function to unregister | |
1913 | * | |
1914 | * Unregister a function that was added to be called by ftrace profiling. | |
1915 | */ | |
1916 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
1917 | { | |
1918 | int ret; | |
1919 | ||
b0fc494f | 1920 | mutex_lock(&ftrace_sysctl_lock); |
3d083395 | 1921 | ret = __unregister_ftrace_function(ops); |
5a45cfe1 | 1922 | ftrace_shutdown(0); |
b0fc494f SR |
1923 | mutex_unlock(&ftrace_sysctl_lock); |
1924 | ||
1925 | return ret; | |
1926 | } | |
1927 | ||
e309b41d | 1928 | int |
b0fc494f | 1929 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
5072c59f | 1930 | struct file *file, void __user *buffer, size_t *lenp, |
b0fc494f SR |
1931 | loff_t *ppos) |
1932 | { | |
1933 | int ret; | |
1934 | ||
4eebcc81 SR |
1935 | if (unlikely(ftrace_disabled)) |
1936 | return -ENODEV; | |
1937 | ||
b0fc494f SR |
1938 | mutex_lock(&ftrace_sysctl_lock); |
1939 | ||
5072c59f | 1940 | ret = proc_dointvec(table, write, file, buffer, lenp, ppos); |
b0fc494f SR |
1941 | |
1942 | if (ret || !write || (last_ftrace_enabled == ftrace_enabled)) | |
1943 | goto out; | |
1944 | ||
1945 | last_ftrace_enabled = ftrace_enabled; | |
1946 | ||
1947 | if (ftrace_enabled) { | |
1948 | ||
1949 | ftrace_startup_sysctl(); | |
1950 | ||
1951 | /* we are starting ftrace again */ | |
1952 | if (ftrace_list != &ftrace_list_end) { | |
1953 | if (ftrace_list->next == &ftrace_list_end) | |
1954 | ftrace_trace_function = ftrace_list->func; | |
1955 | else | |
1956 | ftrace_trace_function = ftrace_list_func; | |
1957 | } | |
1958 | ||
1959 | } else { | |
1960 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
1961 | ftrace_trace_function = ftrace_stub; | |
1962 | ||
1963 | ftrace_shutdown_sysctl(); | |
1964 | } | |
1965 | ||
1966 | out: | |
1967 | mutex_unlock(&ftrace_sysctl_lock); | |
3d083395 | 1968 | return ret; |
16444a8a | 1969 | } |
f17845e5 | 1970 | |
fb52607a | 1971 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 1972 | |
287b6e68 | 1973 | static atomic_t ftrace_graph_active; |
00f57f54 | 1974 | static struct notifier_block ftrace_suspend_notifier; |
e7d3737e | 1975 | |
e49dc19c SR |
1976 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
1977 | { | |
1978 | return 0; | |
1979 | } | |
1980 | ||
287b6e68 FW |
1981 | /* The callbacks that hook a function */ |
1982 | trace_func_graph_ret_t ftrace_graph_return = | |
1983 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 1984 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
1985 | |
1986 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
1987 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
1988 | { | |
1989 | int i; | |
1990 | int ret = 0; | |
1991 | unsigned long flags; | |
1992 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; | |
1993 | struct task_struct *g, *t; | |
1994 | ||
1995 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
1996 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
1997 | * sizeof(struct ftrace_ret_stack), | |
1998 | GFP_KERNEL); | |
1999 | if (!ret_stack_list[i]) { | |
2000 | start = 0; | |
2001 | end = i; | |
2002 | ret = -ENOMEM; | |
2003 | goto free; | |
2004 | } | |
2005 | } | |
2006 | ||
2007 | read_lock_irqsave(&tasklist_lock, flags); | |
2008 | do_each_thread(g, t) { | |
2009 | if (start == end) { | |
2010 | ret = -EAGAIN; | |
2011 | goto unlock; | |
2012 | } | |
2013 | ||
2014 | if (t->ret_stack == NULL) { | |
f201ae23 | 2015 | t->curr_ret_stack = -1; |
48d68b20 FW |
2016 | /* Make sure IRQs see the -1 first: */ |
2017 | barrier(); | |
2018 | t->ret_stack = ret_stack_list[start++]; | |
380c4b14 | 2019 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 FW |
2020 | atomic_set(&t->trace_overrun, 0); |
2021 | } | |
2022 | } while_each_thread(g, t); | |
2023 | ||
2024 | unlock: | |
2025 | read_unlock_irqrestore(&tasklist_lock, flags); | |
2026 | free: | |
2027 | for (i = start; i < end; i++) | |
2028 | kfree(ret_stack_list[i]); | |
2029 | return ret; | |
2030 | } | |
2031 | ||
2032 | /* Allocate a return stack for each task */ | |
fb52607a | 2033 | static int start_graph_tracing(void) |
f201ae23 FW |
2034 | { |
2035 | struct ftrace_ret_stack **ret_stack_list; | |
2036 | int ret; | |
2037 | ||
2038 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
2039 | sizeof(struct ftrace_ret_stack *), | |
2040 | GFP_KERNEL); | |
2041 | ||
2042 | if (!ret_stack_list) | |
2043 | return -ENOMEM; | |
2044 | ||
2045 | do { | |
2046 | ret = alloc_retstack_tasklist(ret_stack_list); | |
2047 | } while (ret == -EAGAIN); | |
2048 | ||
2049 | kfree(ret_stack_list); | |
2050 | return ret; | |
2051 | } | |
2052 | ||
00f57f54 FW |
2053 | /* |
2054 | * Hibernation protection. | |
2055 | * The state of the current task is too much unstable during | |
2056 | * suspend/restore to disk. We want to protect against that. | |
2057 | */ | |
2058 | static int | |
2059 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, | |
2060 | void *unused) | |
2061 | { | |
2062 | switch (state) { | |
2063 | case PM_HIBERNATION_PREPARE: | |
2064 | pause_graph_tracing(); | |
2065 | break; | |
2066 | ||
2067 | case PM_POST_HIBERNATION: | |
2068 | unpause_graph_tracing(); | |
2069 | break; | |
2070 | } | |
2071 | return NOTIFY_DONE; | |
2072 | } | |
2073 | ||
287b6e68 FW |
2074 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
2075 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 2076 | { |
e7d3737e FW |
2077 | int ret = 0; |
2078 | ||
2079 | mutex_lock(&ftrace_sysctl_lock); | |
2080 | ||
00f57f54 FW |
2081 | ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call; |
2082 | register_pm_notifier(&ftrace_suspend_notifier); | |
2083 | ||
287b6e68 | 2084 | atomic_inc(&ftrace_graph_active); |
fb52607a | 2085 | ret = start_graph_tracing(); |
f201ae23 | 2086 | if (ret) { |
287b6e68 | 2087 | atomic_dec(&ftrace_graph_active); |
f201ae23 FW |
2088 | goto out; |
2089 | } | |
e53a6319 | 2090 | |
287b6e68 FW |
2091 | ftrace_graph_return = retfunc; |
2092 | ftrace_graph_entry = entryfunc; | |
e53a6319 | 2093 | |
5a45cfe1 | 2094 | ftrace_startup(FTRACE_START_FUNC_RET); |
e7d3737e FW |
2095 | |
2096 | out: | |
2097 | mutex_unlock(&ftrace_sysctl_lock); | |
2098 | return ret; | |
15e6cb36 FW |
2099 | } |
2100 | ||
fb52607a | 2101 | void unregister_ftrace_graph(void) |
15e6cb36 | 2102 | { |
e7d3737e FW |
2103 | mutex_lock(&ftrace_sysctl_lock); |
2104 | ||
287b6e68 FW |
2105 | atomic_dec(&ftrace_graph_active); |
2106 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 2107 | ftrace_graph_entry = ftrace_graph_entry_stub; |
5a45cfe1 | 2108 | ftrace_shutdown(FTRACE_STOP_FUNC_RET); |
00f57f54 | 2109 | unregister_pm_notifier(&ftrace_suspend_notifier); |
e7d3737e FW |
2110 | |
2111 | mutex_unlock(&ftrace_sysctl_lock); | |
15e6cb36 | 2112 | } |
f201ae23 FW |
2113 | |
2114 | /* Allocate a return stack for newly created task */ | |
fb52607a | 2115 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 2116 | { |
287b6e68 | 2117 | if (atomic_read(&ftrace_graph_active)) { |
f201ae23 FW |
2118 | t->ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH |
2119 | * sizeof(struct ftrace_ret_stack), | |
2120 | GFP_KERNEL); | |
2121 | if (!t->ret_stack) | |
2122 | return; | |
2123 | t->curr_ret_stack = -1; | |
380c4b14 | 2124 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 FW |
2125 | atomic_set(&t->trace_overrun, 0); |
2126 | } else | |
2127 | t->ret_stack = NULL; | |
2128 | } | |
2129 | ||
fb52607a | 2130 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 2131 | { |
eae849ca FW |
2132 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
2133 | ||
f201ae23 | 2134 | t->ret_stack = NULL; |
eae849ca FW |
2135 | /* NULL must become visible to IRQs before we free it: */ |
2136 | barrier(); | |
2137 | ||
2138 | kfree(ret_stack); | |
f201ae23 | 2139 | } |
14a866c5 SR |
2140 | |
2141 | void ftrace_graph_stop(void) | |
2142 | { | |
2143 | ftrace_stop(); | |
2144 | } | |
15e6cb36 FW |
2145 | #endif |
2146 |