Commit | Line | Data |
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16444a8a ACM |
1 | /* |
2 | * Infrastructure for profiling code inserted by 'gcc -pg'. | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2004-2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally ported from the -rt patch by: | |
8 | * Copyright (C) 2007 Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code in the latency_tracer, that is: | |
11 | * | |
12 | * Copyright (C) 2004-2006 Ingo Molnar | |
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> |
4a2b8dda | 20 | #include <linux/suspend.h> |
5072c59f | 21 | #include <linux/debugfs.h> |
3d083395 | 22 | #include <linux/hardirq.h> |
2d8b820b | 23 | #include <linux/kthread.h> |
5072c59f | 24 | #include <linux/uaccess.h> |
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 | ||
d61f82d0 SR |
267 | enum { |
268 | FTRACE_ENABLE_CALLS = (1 << 0), | |
269 | FTRACE_DISABLE_CALLS = (1 << 1), | |
270 | FTRACE_UPDATE_TRACE_FUNC = (1 << 2), | |
271 | FTRACE_ENABLE_MCOUNT = (1 << 3), | |
272 | FTRACE_DISABLE_MCOUNT = (1 << 4), | |
5a45cfe1 SR |
273 | FTRACE_START_FUNC_RET = (1 << 5), |
274 | FTRACE_STOP_FUNC_RET = (1 << 6), | |
d61f82d0 SR |
275 | }; |
276 | ||
5072c59f SR |
277 | static int ftrace_filtered; |
278 | ||
08f5ac90 | 279 | static LIST_HEAD(ftrace_new_addrs); |
3d083395 | 280 | |
41c52c0d | 281 | static DEFINE_MUTEX(ftrace_regex_lock); |
3d083395 | 282 | |
3c1720f0 SR |
283 | struct ftrace_page { |
284 | struct ftrace_page *next; | |
431aa3fb | 285 | int index; |
3c1720f0 | 286 | struct dyn_ftrace records[]; |
aa5e5cea | 287 | }; |
3c1720f0 SR |
288 | |
289 | #define ENTRIES_PER_PAGE \ | |
290 | ((PAGE_SIZE - sizeof(struct ftrace_page)) / sizeof(struct dyn_ftrace)) | |
291 | ||
292 | /* estimate from running different kernels */ | |
293 | #define NR_TO_INIT 10000 | |
294 | ||
295 | static struct ftrace_page *ftrace_pages_start; | |
296 | static struct ftrace_page *ftrace_pages; | |
297 | ||
37ad5084 SR |
298 | static struct dyn_ftrace *ftrace_free_records; |
299 | ||
265c831c SR |
300 | /* |
301 | * This is a double for. Do not use 'break' to break out of the loop, | |
302 | * you must use a goto. | |
303 | */ | |
304 | #define do_for_each_ftrace_rec(pg, rec) \ | |
305 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
306 | int _____i; \ | |
307 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
308 | rec = &pg->records[_____i]; | |
309 | ||
310 | #define while_for_each_ftrace_rec() \ | |
311 | } \ | |
312 | } | |
ecea656d AS |
313 | |
314 | #ifdef CONFIG_KPROBES | |
f17845e5 IM |
315 | |
316 | static int frozen_record_count; | |
317 | ||
ecea656d AS |
318 | static inline void freeze_record(struct dyn_ftrace *rec) |
319 | { | |
320 | if (!(rec->flags & FTRACE_FL_FROZEN)) { | |
321 | rec->flags |= FTRACE_FL_FROZEN; | |
322 | frozen_record_count++; | |
323 | } | |
324 | } | |
325 | ||
326 | static inline void unfreeze_record(struct dyn_ftrace *rec) | |
327 | { | |
328 | if (rec->flags & FTRACE_FL_FROZEN) { | |
329 | rec->flags &= ~FTRACE_FL_FROZEN; | |
330 | frozen_record_count--; | |
331 | } | |
332 | } | |
333 | ||
334 | static inline int record_frozen(struct dyn_ftrace *rec) | |
335 | { | |
336 | return rec->flags & FTRACE_FL_FROZEN; | |
337 | } | |
338 | #else | |
339 | # define freeze_record(rec) ({ 0; }) | |
340 | # define unfreeze_record(rec) ({ 0; }) | |
341 | # define record_frozen(rec) ({ 0; }) | |
342 | #endif /* CONFIG_KPROBES */ | |
343 | ||
e309b41d | 344 | static void ftrace_free_rec(struct dyn_ftrace *rec) |
37ad5084 | 345 | { |
37ad5084 SR |
346 | rec->ip = (unsigned long)ftrace_free_records; |
347 | ftrace_free_records = rec; | |
348 | rec->flags |= FTRACE_FL_FREE; | |
349 | } | |
350 | ||
fed1939c SR |
351 | void ftrace_release(void *start, unsigned long size) |
352 | { | |
353 | struct dyn_ftrace *rec; | |
354 | struct ftrace_page *pg; | |
355 | unsigned long s = (unsigned long)start; | |
356 | unsigned long e = s + size; | |
fed1939c | 357 | |
00fd61ae | 358 | if (ftrace_disabled || !start) |
fed1939c SR |
359 | return; |
360 | ||
99ecdc43 | 361 | /* should not be called from interrupt context */ |
fed1939c SR |
362 | spin_lock(&ftrace_lock); |
363 | ||
265c831c SR |
364 | do_for_each_ftrace_rec(pg, rec) { |
365 | if ((rec->ip >= s) && (rec->ip < e)) | |
366 | ftrace_free_rec(rec); | |
367 | } while_for_each_ftrace_rec(); | |
fed1939c | 368 | |
fed1939c | 369 | spin_unlock(&ftrace_lock); |
fed1939c SR |
370 | } |
371 | ||
e309b41d | 372 | static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip) |
3c1720f0 | 373 | { |
37ad5084 SR |
374 | struct dyn_ftrace *rec; |
375 | ||
376 | /* First check for freed records */ | |
377 | if (ftrace_free_records) { | |
378 | rec = ftrace_free_records; | |
379 | ||
37ad5084 | 380 | if (unlikely(!(rec->flags & FTRACE_FL_FREE))) { |
6912896e | 381 | FTRACE_WARN_ON_ONCE(1); |
37ad5084 SR |
382 | ftrace_free_records = NULL; |
383 | return NULL; | |
384 | } | |
385 | ||
386 | ftrace_free_records = (void *)rec->ip; | |
387 | memset(rec, 0, sizeof(*rec)); | |
388 | return rec; | |
389 | } | |
390 | ||
3c1720f0 | 391 | if (ftrace_pages->index == ENTRIES_PER_PAGE) { |
08f5ac90 SR |
392 | if (!ftrace_pages->next) { |
393 | /* allocate another page */ | |
394 | ftrace_pages->next = | |
395 | (void *)get_zeroed_page(GFP_KERNEL); | |
396 | if (!ftrace_pages->next) | |
397 | return NULL; | |
398 | } | |
3c1720f0 SR |
399 | ftrace_pages = ftrace_pages->next; |
400 | } | |
401 | ||
402 | return &ftrace_pages->records[ftrace_pages->index++]; | |
403 | } | |
404 | ||
08f5ac90 | 405 | static struct dyn_ftrace * |
d61f82d0 | 406 | ftrace_record_ip(unsigned long ip) |
3d083395 | 407 | { |
08f5ac90 | 408 | struct dyn_ftrace *rec; |
3d083395 | 409 | |
f3c7ac40 | 410 | if (ftrace_disabled) |
08f5ac90 | 411 | return NULL; |
3d083395 | 412 | |
08f5ac90 SR |
413 | rec = ftrace_alloc_dyn_node(ip); |
414 | if (!rec) | |
415 | return NULL; | |
3d083395 | 416 | |
08f5ac90 | 417 | rec->ip = ip; |
3d083395 | 418 | |
08f5ac90 | 419 | list_add(&rec->list, &ftrace_new_addrs); |
3d083395 | 420 | |
08f5ac90 | 421 | return rec; |
3d083395 SR |
422 | } |
423 | ||
b17e8a37 SR |
424 | static void print_ip_ins(const char *fmt, unsigned char *p) |
425 | { | |
426 | int i; | |
427 | ||
428 | printk(KERN_CONT "%s", fmt); | |
429 | ||
430 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
431 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
432 | } | |
433 | ||
31e88909 | 434 | static void ftrace_bug(int failed, unsigned long ip) |
b17e8a37 SR |
435 | { |
436 | switch (failed) { | |
437 | case -EFAULT: | |
438 | FTRACE_WARN_ON_ONCE(1); | |
439 | pr_info("ftrace faulted on modifying "); | |
440 | print_ip_sym(ip); | |
441 | break; | |
442 | case -EINVAL: | |
443 | FTRACE_WARN_ON_ONCE(1); | |
444 | pr_info("ftrace failed to modify "); | |
445 | print_ip_sym(ip); | |
b17e8a37 | 446 | print_ip_ins(" actual: ", (unsigned char *)ip); |
b17e8a37 SR |
447 | printk(KERN_CONT "\n"); |
448 | break; | |
449 | case -EPERM: | |
450 | FTRACE_WARN_ON_ONCE(1); | |
451 | pr_info("ftrace faulted on writing "); | |
452 | print_ip_sym(ip); | |
453 | break; | |
454 | default: | |
455 | FTRACE_WARN_ON_ONCE(1); | |
456 | pr_info("ftrace faulted on unknown error "); | |
457 | print_ip_sym(ip); | |
458 | } | |
459 | } | |
460 | ||
3c1720f0 | 461 | |
0eb96701 | 462 | static int |
31e88909 | 463 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) |
5072c59f | 464 | { |
41c52c0d | 465 | unsigned long ip, fl; |
e7d3737e FW |
466 | unsigned long ftrace_addr; |
467 | ||
f0001207 | 468 | ftrace_addr = (unsigned long)FTRACE_ADDR; |
5072c59f SR |
469 | |
470 | ip = rec->ip; | |
471 | ||
982c350b SR |
472 | /* |
473 | * If this record is not to be traced and | |
474 | * it is not enabled then do nothing. | |
475 | * | |
476 | * If this record is not to be traced and | |
57794a9d | 477 | * it is enabled then disable it. |
982c350b SR |
478 | * |
479 | */ | |
480 | if (rec->flags & FTRACE_FL_NOTRACE) { | |
481 | if (rec->flags & FTRACE_FL_ENABLED) | |
482 | rec->flags &= ~FTRACE_FL_ENABLED; | |
483 | else | |
484 | return 0; | |
485 | ||
486 | } else if (ftrace_filtered && enable) { | |
5072c59f | 487 | /* |
982c350b | 488 | * Filtering is on: |
5072c59f | 489 | */ |
a4500b84 | 490 | |
982c350b | 491 | fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED); |
5072c59f | 492 | |
982c350b SR |
493 | /* Record is filtered and enabled, do nothing */ |
494 | if (fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED)) | |
0eb96701 | 495 | return 0; |
5072c59f | 496 | |
57794a9d | 497 | /* Record is not filtered or enabled, do nothing */ |
982c350b SR |
498 | if (!fl) |
499 | return 0; | |
500 | ||
501 | /* Record is not filtered but enabled, disable it */ | |
502 | if (fl == FTRACE_FL_ENABLED) | |
5072c59f | 503 | rec->flags &= ~FTRACE_FL_ENABLED; |
982c350b SR |
504 | else |
505 | /* Otherwise record is filtered but not enabled, enable it */ | |
5072c59f | 506 | rec->flags |= FTRACE_FL_ENABLED; |
5072c59f | 507 | } else { |
982c350b | 508 | /* Disable or not filtered */ |
5072c59f | 509 | |
41c52c0d | 510 | if (enable) { |
982c350b | 511 | /* if record is enabled, do nothing */ |
5072c59f | 512 | if (rec->flags & FTRACE_FL_ENABLED) |
0eb96701 | 513 | return 0; |
982c350b | 514 | |
5072c59f | 515 | rec->flags |= FTRACE_FL_ENABLED; |
982c350b | 516 | |
5072c59f | 517 | } else { |
982c350b | 518 | |
57794a9d | 519 | /* if record is not enabled, do nothing */ |
5072c59f | 520 | if (!(rec->flags & FTRACE_FL_ENABLED)) |
0eb96701 | 521 | return 0; |
982c350b | 522 | |
5072c59f SR |
523 | rec->flags &= ~FTRACE_FL_ENABLED; |
524 | } | |
525 | } | |
526 | ||
982c350b | 527 | if (rec->flags & FTRACE_FL_ENABLED) |
e7d3737e | 528 | return ftrace_make_call(rec, ftrace_addr); |
31e88909 | 529 | else |
e7d3737e | 530 | return ftrace_make_nop(NULL, rec, ftrace_addr); |
5072c59f SR |
531 | } |
532 | ||
e309b41d | 533 | static void ftrace_replace_code(int enable) |
3c1720f0 | 534 | { |
265c831c | 535 | int failed; |
3c1720f0 SR |
536 | struct dyn_ftrace *rec; |
537 | struct ftrace_page *pg; | |
3c1720f0 | 538 | |
265c831c SR |
539 | do_for_each_ftrace_rec(pg, rec) { |
540 | /* | |
541 | * Skip over free records and records that have | |
542 | * failed. | |
543 | */ | |
544 | if (rec->flags & FTRACE_FL_FREE || | |
545 | rec->flags & FTRACE_FL_FAILED) | |
546 | continue; | |
547 | ||
548 | /* ignore updates to this record's mcount site */ | |
549 | if (get_kprobe((void *)rec->ip)) { | |
550 | freeze_record(rec); | |
551 | continue; | |
552 | } else { | |
553 | unfreeze_record(rec); | |
554 | } | |
f22f9a89 | 555 | |
265c831c SR |
556 | failed = __ftrace_replace_code(rec, enable); |
557 | if (failed && (rec->flags & FTRACE_FL_CONVERTED)) { | |
558 | rec->flags |= FTRACE_FL_FAILED; | |
559 | if ((system_state == SYSTEM_BOOTING) || | |
560 | !core_kernel_text(rec->ip)) { | |
561 | ftrace_free_rec(rec); | |
562 | } else | |
563 | ftrace_bug(failed, rec->ip); | |
3c1720f0 | 564 | } |
265c831c | 565 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
566 | } |
567 | ||
492a7ea5 | 568 | static int |
31e88909 | 569 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 SR |
570 | { |
571 | unsigned long ip; | |
593eb8a2 | 572 | int ret; |
3c1720f0 SR |
573 | |
574 | ip = rec->ip; | |
575 | ||
25aac9dc | 576 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
593eb8a2 | 577 | if (ret) { |
31e88909 | 578 | ftrace_bug(ret, ip); |
3c1720f0 | 579 | rec->flags |= FTRACE_FL_FAILED; |
492a7ea5 | 580 | return 0; |
37ad5084 | 581 | } |
492a7ea5 | 582 | return 1; |
3c1720f0 SR |
583 | } |
584 | ||
e309b41d | 585 | static int __ftrace_modify_code(void *data) |
3d083395 | 586 | { |
d61f82d0 SR |
587 | int *command = data; |
588 | ||
a3583244 | 589 | if (*command & FTRACE_ENABLE_CALLS) |
d61f82d0 | 590 | ftrace_replace_code(1); |
a3583244 | 591 | else if (*command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
592 | ftrace_replace_code(0); |
593 | ||
594 | if (*command & FTRACE_UPDATE_TRACE_FUNC) | |
595 | ftrace_update_ftrace_func(ftrace_trace_function); | |
596 | ||
5a45cfe1 SR |
597 | if (*command & FTRACE_START_FUNC_RET) |
598 | ftrace_enable_ftrace_graph_caller(); | |
599 | else if (*command & FTRACE_STOP_FUNC_RET) | |
600 | ftrace_disable_ftrace_graph_caller(); | |
601 | ||
d61f82d0 | 602 | return 0; |
3d083395 SR |
603 | } |
604 | ||
e309b41d | 605 | static void ftrace_run_update_code(int command) |
3d083395 | 606 | { |
784e2d76 | 607 | stop_machine(__ftrace_modify_code, &command, NULL); |
3d083395 SR |
608 | } |
609 | ||
d61f82d0 | 610 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 611 | static int ftrace_start_up; |
df4fc315 SR |
612 | |
613 | static void ftrace_startup_enable(int command) | |
614 | { | |
615 | if (saved_ftrace_func != ftrace_trace_function) { | |
616 | saved_ftrace_func = ftrace_trace_function; | |
617 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
618 | } | |
619 | ||
620 | if (!command || !ftrace_enabled) | |
621 | return; | |
622 | ||
623 | ftrace_run_update_code(command); | |
624 | } | |
d61f82d0 | 625 | |
5a45cfe1 | 626 | static void ftrace_startup(int command) |
3d083395 | 627 | { |
4eebcc81 SR |
628 | if (unlikely(ftrace_disabled)) |
629 | return; | |
630 | ||
cb7be3b2 | 631 | mutex_lock(&ftrace_start_lock); |
60a7ecf4 | 632 | ftrace_start_up++; |
982c350b | 633 | command |= FTRACE_ENABLE_CALLS; |
d61f82d0 | 634 | |
df4fc315 | 635 | ftrace_startup_enable(command); |
3d083395 | 636 | |
cb7be3b2 | 637 | mutex_unlock(&ftrace_start_lock); |
3d083395 SR |
638 | } |
639 | ||
5a45cfe1 | 640 | static void ftrace_shutdown(int command) |
3d083395 | 641 | { |
4eebcc81 SR |
642 | if (unlikely(ftrace_disabled)) |
643 | return; | |
644 | ||
cb7be3b2 | 645 | mutex_lock(&ftrace_start_lock); |
60a7ecf4 SR |
646 | ftrace_start_up--; |
647 | if (!ftrace_start_up) | |
d61f82d0 | 648 | command |= FTRACE_DISABLE_CALLS; |
3d083395 | 649 | |
d61f82d0 SR |
650 | if (saved_ftrace_func != ftrace_trace_function) { |
651 | saved_ftrace_func = ftrace_trace_function; | |
652 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
653 | } | |
3d083395 | 654 | |
d61f82d0 SR |
655 | if (!command || !ftrace_enabled) |
656 | goto out; | |
657 | ||
658 | ftrace_run_update_code(command); | |
3d083395 | 659 | out: |
cb7be3b2 | 660 | mutex_unlock(&ftrace_start_lock); |
3d083395 SR |
661 | } |
662 | ||
e309b41d | 663 | static void ftrace_startup_sysctl(void) |
b0fc494f | 664 | { |
d61f82d0 SR |
665 | int command = FTRACE_ENABLE_MCOUNT; |
666 | ||
4eebcc81 SR |
667 | if (unlikely(ftrace_disabled)) |
668 | return; | |
669 | ||
cb7be3b2 | 670 | mutex_lock(&ftrace_start_lock); |
d61f82d0 SR |
671 | /* Force update next time */ |
672 | saved_ftrace_func = NULL; | |
60a7ecf4 SR |
673 | /* ftrace_start_up is true if we want ftrace running */ |
674 | if (ftrace_start_up) | |
d61f82d0 SR |
675 | command |= FTRACE_ENABLE_CALLS; |
676 | ||
677 | ftrace_run_update_code(command); | |
cb7be3b2 | 678 | mutex_unlock(&ftrace_start_lock); |
b0fc494f SR |
679 | } |
680 | ||
e309b41d | 681 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 682 | { |
d61f82d0 SR |
683 | int command = FTRACE_DISABLE_MCOUNT; |
684 | ||
4eebcc81 SR |
685 | if (unlikely(ftrace_disabled)) |
686 | return; | |
687 | ||
cb7be3b2 | 688 | mutex_lock(&ftrace_start_lock); |
60a7ecf4 SR |
689 | /* ftrace_start_up is true if ftrace is running */ |
690 | if (ftrace_start_up) | |
d61f82d0 SR |
691 | command |= FTRACE_DISABLE_CALLS; |
692 | ||
693 | ftrace_run_update_code(command); | |
cb7be3b2 | 694 | mutex_unlock(&ftrace_start_lock); |
b0fc494f SR |
695 | } |
696 | ||
3d083395 SR |
697 | static cycle_t ftrace_update_time; |
698 | static unsigned long ftrace_update_cnt; | |
699 | unsigned long ftrace_update_tot_cnt; | |
700 | ||
31e88909 | 701 | static int ftrace_update_code(struct module *mod) |
3d083395 | 702 | { |
08f5ac90 | 703 | struct dyn_ftrace *p, *t; |
f22f9a89 | 704 | cycle_t start, stop; |
3d083395 | 705 | |
750ed1a4 | 706 | start = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
707 | ftrace_update_cnt = 0; |
708 | ||
08f5ac90 | 709 | list_for_each_entry_safe(p, t, &ftrace_new_addrs, list) { |
3d083395 | 710 | |
08f5ac90 SR |
711 | /* If something went wrong, bail without enabling anything */ |
712 | if (unlikely(ftrace_disabled)) | |
713 | return -1; | |
f22f9a89 | 714 | |
08f5ac90 | 715 | list_del_init(&p->list); |
f22f9a89 | 716 | |
08f5ac90 | 717 | /* convert record (i.e, patch mcount-call with NOP) */ |
31e88909 | 718 | if (ftrace_code_disable(mod, p)) { |
08f5ac90 SR |
719 | p->flags |= FTRACE_FL_CONVERTED; |
720 | ftrace_update_cnt++; | |
721 | } else | |
722 | ftrace_free_rec(p); | |
3d083395 SR |
723 | } |
724 | ||
750ed1a4 | 725 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 SR |
726 | ftrace_update_time = stop - start; |
727 | ftrace_update_tot_cnt += ftrace_update_cnt; | |
728 | ||
16444a8a ACM |
729 | return 0; |
730 | } | |
731 | ||
68bf21aa | 732 | static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) |
3c1720f0 SR |
733 | { |
734 | struct ftrace_page *pg; | |
735 | int cnt; | |
736 | int i; | |
3c1720f0 SR |
737 | |
738 | /* allocate a few pages */ | |
739 | ftrace_pages_start = (void *)get_zeroed_page(GFP_KERNEL); | |
740 | if (!ftrace_pages_start) | |
741 | return -1; | |
742 | ||
743 | /* | |
744 | * Allocate a few more pages. | |
745 | * | |
746 | * TODO: have some parser search vmlinux before | |
747 | * final linking to find all calls to ftrace. | |
748 | * Then we can: | |
749 | * a) know how many pages to allocate. | |
750 | * and/or | |
751 | * b) set up the table then. | |
752 | * | |
753 | * The dynamic code is still necessary for | |
754 | * modules. | |
755 | */ | |
756 | ||
757 | pg = ftrace_pages = ftrace_pages_start; | |
758 | ||
68bf21aa | 759 | cnt = num_to_init / ENTRIES_PER_PAGE; |
08f5ac90 | 760 | pr_info("ftrace: allocating %ld entries in %d pages\n", |
5821e1b7 | 761 | num_to_init, cnt + 1); |
3c1720f0 SR |
762 | |
763 | for (i = 0; i < cnt; i++) { | |
764 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); | |
765 | ||
766 | /* If we fail, we'll try later anyway */ | |
767 | if (!pg->next) | |
768 | break; | |
769 | ||
770 | pg = pg->next; | |
771 | } | |
772 | ||
773 | return 0; | |
774 | } | |
775 | ||
5072c59f SR |
776 | enum { |
777 | FTRACE_ITER_FILTER = (1 << 0), | |
778 | FTRACE_ITER_CONT = (1 << 1), | |
41c52c0d | 779 | FTRACE_ITER_NOTRACE = (1 << 2), |
eb9a7bf0 | 780 | FTRACE_ITER_FAILURES = (1 << 3), |
0c75a3ed | 781 | FTRACE_ITER_PRINTALL = (1 << 4), |
5072c59f SR |
782 | }; |
783 | ||
784 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ | |
785 | ||
786 | struct ftrace_iterator { | |
5072c59f | 787 | struct ftrace_page *pg; |
431aa3fb | 788 | int idx; |
5072c59f SR |
789 | unsigned flags; |
790 | unsigned char buffer[FTRACE_BUFF_MAX+1]; | |
791 | unsigned buffer_idx; | |
792 | unsigned filtered; | |
793 | }; | |
794 | ||
e309b41d | 795 | static void * |
5072c59f SR |
796 | t_next(struct seq_file *m, void *v, loff_t *pos) |
797 | { | |
798 | struct ftrace_iterator *iter = m->private; | |
799 | struct dyn_ftrace *rec = NULL; | |
800 | ||
801 | (*pos)++; | |
802 | ||
0c75a3ed SR |
803 | if (iter->flags & FTRACE_ITER_PRINTALL) |
804 | return NULL; | |
805 | ||
99ecdc43 SR |
806 | /* should not be called from interrupt context */ |
807 | spin_lock(&ftrace_lock); | |
5072c59f SR |
808 | retry: |
809 | if (iter->idx >= iter->pg->index) { | |
810 | if (iter->pg->next) { | |
811 | iter->pg = iter->pg->next; | |
812 | iter->idx = 0; | |
813 | goto retry; | |
50cdaf08 LW |
814 | } else { |
815 | iter->idx = -1; | |
5072c59f SR |
816 | } |
817 | } else { | |
818 | rec = &iter->pg->records[iter->idx++]; | |
a9fdda33 SR |
819 | if ((rec->flags & FTRACE_FL_FREE) || |
820 | ||
821 | (!(iter->flags & FTRACE_ITER_FAILURES) && | |
eb9a7bf0 AS |
822 | (rec->flags & FTRACE_FL_FAILED)) || |
823 | ||
824 | ((iter->flags & FTRACE_ITER_FAILURES) && | |
a9fdda33 | 825 | !(rec->flags & FTRACE_FL_FAILED)) || |
eb9a7bf0 | 826 | |
0183fb1c SR |
827 | ((iter->flags & FTRACE_ITER_FILTER) && |
828 | !(rec->flags & FTRACE_FL_FILTER)) || | |
829 | ||
41c52c0d SR |
830 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
831 | !(rec->flags & FTRACE_FL_NOTRACE))) { | |
5072c59f SR |
832 | rec = NULL; |
833 | goto retry; | |
834 | } | |
835 | } | |
99ecdc43 | 836 | spin_unlock(&ftrace_lock); |
5072c59f | 837 | |
5072c59f SR |
838 | return rec; |
839 | } | |
840 | ||
841 | static void *t_start(struct seq_file *m, loff_t *pos) | |
842 | { | |
843 | struct ftrace_iterator *iter = m->private; | |
844 | void *p = NULL; | |
5072c59f | 845 | |
0c75a3ed SR |
846 | /* |
847 | * For set_ftrace_filter reading, if we have the filter | |
848 | * off, we can short cut and just print out that all | |
849 | * functions are enabled. | |
850 | */ | |
851 | if (iter->flags & FTRACE_ITER_FILTER && !ftrace_filtered) { | |
852 | if (*pos > 0) | |
853 | return NULL; | |
854 | iter->flags |= FTRACE_ITER_PRINTALL; | |
855 | (*pos)++; | |
856 | return iter; | |
857 | } | |
858 | ||
50cdaf08 LW |
859 | if (*pos > 0) { |
860 | if (iter->idx < 0) | |
861 | return p; | |
862 | (*pos)--; | |
863 | iter->idx--; | |
864 | } | |
5821e1b7 | 865 | |
50cdaf08 | 866 | p = t_next(m, p, pos); |
5072c59f SR |
867 | |
868 | return p; | |
869 | } | |
870 | ||
871 | static void t_stop(struct seq_file *m, void *p) | |
872 | { | |
873 | } | |
874 | ||
875 | static int t_show(struct seq_file *m, void *v) | |
876 | { | |
0c75a3ed | 877 | struct ftrace_iterator *iter = m->private; |
5072c59f SR |
878 | struct dyn_ftrace *rec = v; |
879 | char str[KSYM_SYMBOL_LEN]; | |
880 | ||
0c75a3ed SR |
881 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
882 | seq_printf(m, "#### all functions enabled ####\n"); | |
883 | return 0; | |
884 | } | |
885 | ||
5072c59f SR |
886 | if (!rec) |
887 | return 0; | |
888 | ||
889 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
890 | ||
50cdaf08 | 891 | seq_printf(m, "%s\n", str); |
5072c59f SR |
892 | |
893 | return 0; | |
894 | } | |
895 | ||
896 | static struct seq_operations show_ftrace_seq_ops = { | |
897 | .start = t_start, | |
898 | .next = t_next, | |
899 | .stop = t_stop, | |
900 | .show = t_show, | |
901 | }; | |
902 | ||
e309b41d | 903 | static int |
5072c59f SR |
904 | ftrace_avail_open(struct inode *inode, struct file *file) |
905 | { | |
906 | struct ftrace_iterator *iter; | |
907 | int ret; | |
908 | ||
4eebcc81 SR |
909 | if (unlikely(ftrace_disabled)) |
910 | return -ENODEV; | |
911 | ||
5072c59f SR |
912 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
913 | if (!iter) | |
914 | return -ENOMEM; | |
915 | ||
916 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
917 | |
918 | ret = seq_open(file, &show_ftrace_seq_ops); | |
919 | if (!ret) { | |
920 | struct seq_file *m = file->private_data; | |
4bf39a94 | 921 | |
5072c59f | 922 | m->private = iter; |
4bf39a94 | 923 | } else { |
5072c59f | 924 | kfree(iter); |
4bf39a94 | 925 | } |
5072c59f SR |
926 | |
927 | return ret; | |
928 | } | |
929 | ||
930 | int ftrace_avail_release(struct inode *inode, struct file *file) | |
931 | { | |
932 | struct seq_file *m = (struct seq_file *)file->private_data; | |
933 | struct ftrace_iterator *iter = m->private; | |
934 | ||
935 | seq_release(inode, file); | |
936 | kfree(iter); | |
4bf39a94 | 937 | |
5072c59f SR |
938 | return 0; |
939 | } | |
940 | ||
eb9a7bf0 AS |
941 | static int |
942 | ftrace_failures_open(struct inode *inode, struct file *file) | |
943 | { | |
944 | int ret; | |
945 | struct seq_file *m; | |
946 | struct ftrace_iterator *iter; | |
947 | ||
948 | ret = ftrace_avail_open(inode, file); | |
949 | if (!ret) { | |
950 | m = (struct seq_file *)file->private_data; | |
951 | iter = (struct ftrace_iterator *)m->private; | |
952 | iter->flags = FTRACE_ITER_FAILURES; | |
953 | } | |
954 | ||
955 | return ret; | |
956 | } | |
957 | ||
958 | ||
41c52c0d | 959 | static void ftrace_filter_reset(int enable) |
5072c59f SR |
960 | { |
961 | struct ftrace_page *pg; | |
962 | struct dyn_ftrace *rec; | |
41c52c0d | 963 | unsigned long type = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
5072c59f | 964 | |
99ecdc43 SR |
965 | /* should not be called from interrupt context */ |
966 | spin_lock(&ftrace_lock); | |
41c52c0d SR |
967 | if (enable) |
968 | ftrace_filtered = 0; | |
265c831c SR |
969 | do_for_each_ftrace_rec(pg, rec) { |
970 | if (rec->flags & FTRACE_FL_FAILED) | |
971 | continue; | |
972 | rec->flags &= ~type; | |
973 | } while_for_each_ftrace_rec(); | |
974 | ||
99ecdc43 | 975 | spin_unlock(&ftrace_lock); |
5072c59f SR |
976 | } |
977 | ||
e309b41d | 978 | static int |
41c52c0d | 979 | ftrace_regex_open(struct inode *inode, struct file *file, int enable) |
5072c59f SR |
980 | { |
981 | struct ftrace_iterator *iter; | |
982 | int ret = 0; | |
983 | ||
4eebcc81 SR |
984 | if (unlikely(ftrace_disabled)) |
985 | return -ENODEV; | |
986 | ||
5072c59f SR |
987 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
988 | if (!iter) | |
989 | return -ENOMEM; | |
990 | ||
41c52c0d | 991 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
992 | if ((file->f_mode & FMODE_WRITE) && |
993 | !(file->f_flags & O_APPEND)) | |
41c52c0d | 994 | ftrace_filter_reset(enable); |
5072c59f SR |
995 | |
996 | if (file->f_mode & FMODE_READ) { | |
997 | iter->pg = ftrace_pages_start; | |
41c52c0d SR |
998 | iter->flags = enable ? FTRACE_ITER_FILTER : |
999 | FTRACE_ITER_NOTRACE; | |
5072c59f SR |
1000 | |
1001 | ret = seq_open(file, &show_ftrace_seq_ops); | |
1002 | if (!ret) { | |
1003 | struct seq_file *m = file->private_data; | |
1004 | m->private = iter; | |
1005 | } else | |
1006 | kfree(iter); | |
1007 | } else | |
1008 | file->private_data = iter; | |
41c52c0d | 1009 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
1010 | |
1011 | return ret; | |
1012 | } | |
1013 | ||
41c52c0d SR |
1014 | static int |
1015 | ftrace_filter_open(struct inode *inode, struct file *file) | |
1016 | { | |
1017 | return ftrace_regex_open(inode, file, 1); | |
1018 | } | |
1019 | ||
1020 | static int | |
1021 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
1022 | { | |
1023 | return ftrace_regex_open(inode, file, 0); | |
1024 | } | |
1025 | ||
e309b41d | 1026 | static ssize_t |
41c52c0d | 1027 | ftrace_regex_read(struct file *file, char __user *ubuf, |
5072c59f SR |
1028 | size_t cnt, loff_t *ppos) |
1029 | { | |
1030 | if (file->f_mode & FMODE_READ) | |
1031 | return seq_read(file, ubuf, cnt, ppos); | |
1032 | else | |
1033 | return -EPERM; | |
1034 | } | |
1035 | ||
e309b41d | 1036 | static loff_t |
41c52c0d | 1037 | ftrace_regex_lseek(struct file *file, loff_t offset, int origin) |
5072c59f SR |
1038 | { |
1039 | loff_t ret; | |
1040 | ||
1041 | if (file->f_mode & FMODE_READ) | |
1042 | ret = seq_lseek(file, offset, origin); | |
1043 | else | |
1044 | file->f_pos = ret = 1; | |
1045 | ||
1046 | return ret; | |
1047 | } | |
1048 | ||
1049 | enum { | |
1050 | MATCH_FULL, | |
1051 | MATCH_FRONT_ONLY, | |
1052 | MATCH_MIDDLE_ONLY, | |
1053 | MATCH_END_ONLY, | |
1054 | }; | |
1055 | ||
e309b41d | 1056 | static void |
41c52c0d | 1057 | ftrace_match(unsigned char *buff, int len, int enable) |
5072c59f SR |
1058 | { |
1059 | char str[KSYM_SYMBOL_LEN]; | |
1060 | char *search = NULL; | |
1061 | struct ftrace_page *pg; | |
1062 | struct dyn_ftrace *rec; | |
1063 | int type = MATCH_FULL; | |
41c52c0d | 1064 | unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
5072c59f | 1065 | unsigned i, match = 0, search_len = 0; |
ea3a6d6d SR |
1066 | int not = 0; |
1067 | ||
1068 | if (buff[0] == '!') { | |
1069 | not = 1; | |
1070 | buff++; | |
1071 | len--; | |
1072 | } | |
5072c59f SR |
1073 | |
1074 | for (i = 0; i < len; i++) { | |
1075 | if (buff[i] == '*') { | |
1076 | if (!i) { | |
1077 | search = buff + i + 1; | |
1078 | type = MATCH_END_ONLY; | |
1079 | search_len = len - (i + 1); | |
1080 | } else { | |
1081 | if (type == MATCH_END_ONLY) { | |
1082 | type = MATCH_MIDDLE_ONLY; | |
1083 | } else { | |
1084 | match = i; | |
1085 | type = MATCH_FRONT_ONLY; | |
1086 | } | |
1087 | buff[i] = 0; | |
1088 | break; | |
1089 | } | |
1090 | } | |
1091 | } | |
1092 | ||
99ecdc43 SR |
1093 | /* should not be called from interrupt context */ |
1094 | spin_lock(&ftrace_lock); | |
41c52c0d SR |
1095 | if (enable) |
1096 | ftrace_filtered = 1; | |
265c831c SR |
1097 | do_for_each_ftrace_rec(pg, rec) { |
1098 | int matched = 0; | |
1099 | char *ptr; | |
1100 | ||
1101 | if (rec->flags & FTRACE_FL_FAILED) | |
1102 | continue; | |
1103 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
1104 | switch (type) { | |
1105 | case MATCH_FULL: | |
1106 | if (strcmp(str, buff) == 0) | |
1107 | matched = 1; | |
1108 | break; | |
1109 | case MATCH_FRONT_ONLY: | |
1110 | if (memcmp(str, buff, match) == 0) | |
1111 | matched = 1; | |
1112 | break; | |
1113 | case MATCH_MIDDLE_ONLY: | |
1114 | if (strstr(str, search)) | |
1115 | matched = 1; | |
1116 | break; | |
1117 | case MATCH_END_ONLY: | |
1118 | ptr = strstr(str, search); | |
1119 | if (ptr && (ptr[search_len] == 0)) | |
1120 | matched = 1; | |
1121 | break; | |
5072c59f | 1122 | } |
265c831c SR |
1123 | if (matched) { |
1124 | if (not) | |
1125 | rec->flags &= ~flag; | |
1126 | else | |
1127 | rec->flags |= flag; | |
1128 | } | |
1129 | } while_for_each_ftrace_rec(); | |
99ecdc43 | 1130 | spin_unlock(&ftrace_lock); |
5072c59f SR |
1131 | } |
1132 | ||
e309b41d | 1133 | static ssize_t |
41c52c0d SR |
1134 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
1135 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
1136 | { |
1137 | struct ftrace_iterator *iter; | |
1138 | char ch; | |
1139 | size_t read = 0; | |
1140 | ssize_t ret; | |
1141 | ||
1142 | if (!cnt || cnt < 0) | |
1143 | return 0; | |
1144 | ||
41c52c0d | 1145 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
1146 | |
1147 | if (file->f_mode & FMODE_READ) { | |
1148 | struct seq_file *m = file->private_data; | |
1149 | iter = m->private; | |
1150 | } else | |
1151 | iter = file->private_data; | |
1152 | ||
1153 | if (!*ppos) { | |
1154 | iter->flags &= ~FTRACE_ITER_CONT; | |
1155 | iter->buffer_idx = 0; | |
1156 | } | |
1157 | ||
1158 | ret = get_user(ch, ubuf++); | |
1159 | if (ret) | |
1160 | goto out; | |
1161 | read++; | |
1162 | cnt--; | |
1163 | ||
1164 | if (!(iter->flags & ~FTRACE_ITER_CONT)) { | |
1165 | /* skip white space */ | |
1166 | while (cnt && isspace(ch)) { | |
1167 | ret = get_user(ch, ubuf++); | |
1168 | if (ret) | |
1169 | goto out; | |
1170 | read++; | |
1171 | cnt--; | |
1172 | } | |
1173 | ||
5072c59f SR |
1174 | if (isspace(ch)) { |
1175 | file->f_pos += read; | |
1176 | ret = read; | |
1177 | goto out; | |
1178 | } | |
1179 | ||
1180 | iter->buffer_idx = 0; | |
1181 | } | |
1182 | ||
1183 | while (cnt && !isspace(ch)) { | |
1184 | if (iter->buffer_idx < FTRACE_BUFF_MAX) | |
1185 | iter->buffer[iter->buffer_idx++] = ch; | |
1186 | else { | |
1187 | ret = -EINVAL; | |
1188 | goto out; | |
1189 | } | |
1190 | ret = get_user(ch, ubuf++); | |
1191 | if (ret) | |
1192 | goto out; | |
1193 | read++; | |
1194 | cnt--; | |
1195 | } | |
1196 | ||
1197 | if (isspace(ch)) { | |
1198 | iter->filtered++; | |
1199 | iter->buffer[iter->buffer_idx] = 0; | |
41c52c0d | 1200 | ftrace_match(iter->buffer, iter->buffer_idx, enable); |
5072c59f SR |
1201 | iter->buffer_idx = 0; |
1202 | } else | |
1203 | iter->flags |= FTRACE_ITER_CONT; | |
1204 | ||
1205 | ||
1206 | file->f_pos += read; | |
1207 | ||
1208 | ret = read; | |
1209 | out: | |
41c52c0d | 1210 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
1211 | |
1212 | return ret; | |
1213 | } | |
1214 | ||
41c52c0d SR |
1215 | static ssize_t |
1216 | ftrace_filter_write(struct file *file, const char __user *ubuf, | |
1217 | size_t cnt, loff_t *ppos) | |
1218 | { | |
1219 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
1220 | } | |
1221 | ||
1222 | static ssize_t | |
1223 | ftrace_notrace_write(struct file *file, const char __user *ubuf, | |
1224 | size_t cnt, loff_t *ppos) | |
1225 | { | |
1226 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
1227 | } | |
1228 | ||
1229 | static void | |
1230 | ftrace_set_regex(unsigned char *buf, int len, int reset, int enable) | |
1231 | { | |
1232 | if (unlikely(ftrace_disabled)) | |
1233 | return; | |
1234 | ||
1235 | mutex_lock(&ftrace_regex_lock); | |
1236 | if (reset) | |
1237 | ftrace_filter_reset(enable); | |
1238 | if (buf) | |
1239 | ftrace_match(buf, len, enable); | |
1240 | mutex_unlock(&ftrace_regex_lock); | |
1241 | } | |
1242 | ||
77a2b37d SR |
1243 | /** |
1244 | * ftrace_set_filter - set a function to filter on in ftrace | |
1245 | * @buf - the string that holds the function filter text. | |
1246 | * @len - the length of the string. | |
1247 | * @reset - non zero to reset all filters before applying this filter. | |
1248 | * | |
1249 | * Filters denote which functions should be enabled when tracing is enabled. | |
1250 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
1251 | */ | |
e309b41d | 1252 | void ftrace_set_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 1253 | { |
41c52c0d SR |
1254 | ftrace_set_regex(buf, len, reset, 1); |
1255 | } | |
4eebcc81 | 1256 | |
41c52c0d SR |
1257 | /** |
1258 | * ftrace_set_notrace - set a function to not trace in ftrace | |
1259 | * @buf - the string that holds the function notrace text. | |
1260 | * @len - the length of the string. | |
1261 | * @reset - non zero to reset all filters before applying this filter. | |
1262 | * | |
1263 | * Notrace Filters denote which functions should not be enabled when tracing | |
1264 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
1265 | * for tracing. | |
1266 | */ | |
1267 | void ftrace_set_notrace(unsigned char *buf, int len, int reset) | |
1268 | { | |
1269 | ftrace_set_regex(buf, len, reset, 0); | |
77a2b37d SR |
1270 | } |
1271 | ||
e309b41d | 1272 | static int |
41c52c0d | 1273 | ftrace_regex_release(struct inode *inode, struct file *file, int enable) |
5072c59f SR |
1274 | { |
1275 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1276 | struct ftrace_iterator *iter; | |
1277 | ||
41c52c0d | 1278 | mutex_lock(&ftrace_regex_lock); |
5072c59f SR |
1279 | if (file->f_mode & FMODE_READ) { |
1280 | iter = m->private; | |
1281 | ||
1282 | seq_release(inode, file); | |
1283 | } else | |
1284 | iter = file->private_data; | |
1285 | ||
1286 | if (iter->buffer_idx) { | |
1287 | iter->filtered++; | |
1288 | iter->buffer[iter->buffer_idx] = 0; | |
41c52c0d | 1289 | ftrace_match(iter->buffer, iter->buffer_idx, enable); |
5072c59f SR |
1290 | } |
1291 | ||
1292 | mutex_lock(&ftrace_sysctl_lock); | |
cb7be3b2 | 1293 | mutex_lock(&ftrace_start_lock); |
ee02a2e5 | 1294 | if (ftrace_start_up && ftrace_enabled) |
5072c59f | 1295 | ftrace_run_update_code(FTRACE_ENABLE_CALLS); |
cb7be3b2 | 1296 | mutex_unlock(&ftrace_start_lock); |
5072c59f SR |
1297 | mutex_unlock(&ftrace_sysctl_lock); |
1298 | ||
1299 | kfree(iter); | |
41c52c0d | 1300 | mutex_unlock(&ftrace_regex_lock); |
5072c59f SR |
1301 | return 0; |
1302 | } | |
1303 | ||
41c52c0d SR |
1304 | static int |
1305 | ftrace_filter_release(struct inode *inode, struct file *file) | |
1306 | { | |
1307 | return ftrace_regex_release(inode, file, 1); | |
1308 | } | |
1309 | ||
1310 | static int | |
1311 | ftrace_notrace_release(struct inode *inode, struct file *file) | |
1312 | { | |
1313 | return ftrace_regex_release(inode, file, 0); | |
1314 | } | |
1315 | ||
5072c59f SR |
1316 | static struct file_operations ftrace_avail_fops = { |
1317 | .open = ftrace_avail_open, | |
1318 | .read = seq_read, | |
1319 | .llseek = seq_lseek, | |
1320 | .release = ftrace_avail_release, | |
1321 | }; | |
1322 | ||
eb9a7bf0 AS |
1323 | static struct file_operations ftrace_failures_fops = { |
1324 | .open = ftrace_failures_open, | |
1325 | .read = seq_read, | |
1326 | .llseek = seq_lseek, | |
1327 | .release = ftrace_avail_release, | |
1328 | }; | |
1329 | ||
5072c59f SR |
1330 | static struct file_operations ftrace_filter_fops = { |
1331 | .open = ftrace_filter_open, | |
41c52c0d | 1332 | .read = ftrace_regex_read, |
5072c59f | 1333 | .write = ftrace_filter_write, |
41c52c0d | 1334 | .llseek = ftrace_regex_lseek, |
5072c59f SR |
1335 | .release = ftrace_filter_release, |
1336 | }; | |
1337 | ||
41c52c0d SR |
1338 | static struct file_operations ftrace_notrace_fops = { |
1339 | .open = ftrace_notrace_open, | |
1340 | .read = ftrace_regex_read, | |
1341 | .write = ftrace_notrace_write, | |
1342 | .llseek = ftrace_regex_lseek, | |
1343 | .release = ftrace_notrace_release, | |
1344 | }; | |
1345 | ||
ea4e2bc4 SR |
1346 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
1347 | ||
1348 | static DEFINE_MUTEX(graph_lock); | |
1349 | ||
1350 | int ftrace_graph_count; | |
1351 | unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; | |
1352 | ||
1353 | static void * | |
1354 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
1355 | { | |
1356 | unsigned long *array = m->private; | |
1357 | int index = *pos; | |
1358 | ||
1359 | (*pos)++; | |
1360 | ||
1361 | if (index >= ftrace_graph_count) | |
1362 | return NULL; | |
1363 | ||
1364 | return &array[index]; | |
1365 | } | |
1366 | ||
1367 | static void *g_start(struct seq_file *m, loff_t *pos) | |
1368 | { | |
1369 | void *p = NULL; | |
1370 | ||
1371 | mutex_lock(&graph_lock); | |
1372 | ||
1373 | p = g_next(m, p, pos); | |
1374 | ||
1375 | return p; | |
1376 | } | |
1377 | ||
1378 | static void g_stop(struct seq_file *m, void *p) | |
1379 | { | |
1380 | mutex_unlock(&graph_lock); | |
1381 | } | |
1382 | ||
1383 | static int g_show(struct seq_file *m, void *v) | |
1384 | { | |
1385 | unsigned long *ptr = v; | |
1386 | char str[KSYM_SYMBOL_LEN]; | |
1387 | ||
1388 | if (!ptr) | |
1389 | return 0; | |
1390 | ||
1391 | kallsyms_lookup(*ptr, NULL, NULL, NULL, str); | |
1392 | ||
1393 | seq_printf(m, "%s\n", str); | |
1394 | ||
1395 | return 0; | |
1396 | } | |
1397 | ||
1398 | static struct seq_operations ftrace_graph_seq_ops = { | |
1399 | .start = g_start, | |
1400 | .next = g_next, | |
1401 | .stop = g_stop, | |
1402 | .show = g_show, | |
1403 | }; | |
1404 | ||
1405 | static int | |
1406 | ftrace_graph_open(struct inode *inode, struct file *file) | |
1407 | { | |
1408 | int ret = 0; | |
1409 | ||
1410 | if (unlikely(ftrace_disabled)) | |
1411 | return -ENODEV; | |
1412 | ||
1413 | mutex_lock(&graph_lock); | |
1414 | if ((file->f_mode & FMODE_WRITE) && | |
1415 | !(file->f_flags & O_APPEND)) { | |
1416 | ftrace_graph_count = 0; | |
1417 | memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); | |
1418 | } | |
1419 | ||
1420 | if (file->f_mode & FMODE_READ) { | |
1421 | ret = seq_open(file, &ftrace_graph_seq_ops); | |
1422 | if (!ret) { | |
1423 | struct seq_file *m = file->private_data; | |
1424 | m->private = ftrace_graph_funcs; | |
1425 | } | |
1426 | } else | |
1427 | file->private_data = ftrace_graph_funcs; | |
1428 | mutex_unlock(&graph_lock); | |
1429 | ||
1430 | return ret; | |
1431 | } | |
1432 | ||
1433 | static ssize_t | |
1434 | ftrace_graph_read(struct file *file, char __user *ubuf, | |
1435 | size_t cnt, loff_t *ppos) | |
1436 | { | |
1437 | if (file->f_mode & FMODE_READ) | |
1438 | return seq_read(file, ubuf, cnt, ppos); | |
1439 | else | |
1440 | return -EPERM; | |
1441 | } | |
1442 | ||
1443 | static int | |
1444 | ftrace_set_func(unsigned long *array, int idx, char *buffer) | |
1445 | { | |
1446 | char str[KSYM_SYMBOL_LEN]; | |
1447 | struct dyn_ftrace *rec; | |
1448 | struct ftrace_page *pg; | |
1449 | int found = 0; | |
265c831c | 1450 | int j; |
ea4e2bc4 SR |
1451 | |
1452 | if (ftrace_disabled) | |
1453 | return -ENODEV; | |
1454 | ||
1455 | /* should not be called from interrupt context */ | |
1456 | spin_lock(&ftrace_lock); | |
1457 | ||
265c831c SR |
1458 | do_for_each_ftrace_rec(pg, rec) { |
1459 | ||
1460 | if (rec->flags & (FTRACE_FL_FAILED | FTRACE_FL_FREE)) | |
1461 | continue; | |
1462 | ||
1463 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | |
1464 | if (strcmp(str, buffer) == 0) { | |
1465 | /* Return 1 if we add it to the array */ | |
1466 | found = 1; | |
1467 | for (j = 0; j < idx; j++) | |
1468 | if (array[j] == rec->ip) { | |
1469 | found = 0; | |
1470 | break; | |
1471 | } | |
1472 | if (found) | |
1473 | array[idx] = rec->ip; | |
1474 | goto out; | |
ea4e2bc4 | 1475 | } |
265c831c SR |
1476 | } while_for_each_ftrace_rec(); |
1477 | out: | |
ea4e2bc4 SR |
1478 | spin_unlock(&ftrace_lock); |
1479 | ||
1480 | return found ? 0 : -EINVAL; | |
1481 | } | |
1482 | ||
1483 | static ssize_t | |
1484 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
1485 | size_t cnt, loff_t *ppos) | |
1486 | { | |
1487 | unsigned char buffer[FTRACE_BUFF_MAX+1]; | |
1488 | unsigned long *array; | |
1489 | size_t read = 0; | |
1490 | ssize_t ret; | |
1491 | int index = 0; | |
1492 | char ch; | |
1493 | ||
1494 | if (!cnt || cnt < 0) | |
1495 | return 0; | |
1496 | ||
1497 | mutex_lock(&graph_lock); | |
1498 | ||
1499 | if (ftrace_graph_count >= FTRACE_GRAPH_MAX_FUNCS) { | |
1500 | ret = -EBUSY; | |
1501 | goto out; | |
1502 | } | |
1503 | ||
1504 | if (file->f_mode & FMODE_READ) { | |
1505 | struct seq_file *m = file->private_data; | |
1506 | array = m->private; | |
1507 | } else | |
1508 | array = file->private_data; | |
1509 | ||
1510 | ret = get_user(ch, ubuf++); | |
1511 | if (ret) | |
1512 | goto out; | |
1513 | read++; | |
1514 | cnt--; | |
1515 | ||
1516 | /* skip white space */ | |
1517 | while (cnt && isspace(ch)) { | |
1518 | ret = get_user(ch, ubuf++); | |
1519 | if (ret) | |
1520 | goto out; | |
1521 | read++; | |
1522 | cnt--; | |
1523 | } | |
1524 | ||
1525 | if (isspace(ch)) { | |
1526 | *ppos += read; | |
1527 | ret = read; | |
1528 | goto out; | |
1529 | } | |
1530 | ||
1531 | while (cnt && !isspace(ch)) { | |
1532 | if (index < FTRACE_BUFF_MAX) | |
1533 | buffer[index++] = ch; | |
1534 | else { | |
1535 | ret = -EINVAL; | |
1536 | goto out; | |
1537 | } | |
1538 | ret = get_user(ch, ubuf++); | |
1539 | if (ret) | |
1540 | goto out; | |
1541 | read++; | |
1542 | cnt--; | |
1543 | } | |
1544 | buffer[index] = 0; | |
1545 | ||
1546 | /* we allow only one at a time */ | |
1547 | ret = ftrace_set_func(array, ftrace_graph_count, buffer); | |
1548 | if (ret) | |
1549 | goto out; | |
1550 | ||
1551 | ftrace_graph_count++; | |
1552 | ||
1553 | file->f_pos += read; | |
1554 | ||
1555 | ret = read; | |
1556 | out: | |
1557 | mutex_unlock(&graph_lock); | |
1558 | ||
1559 | return ret; | |
1560 | } | |
1561 | ||
1562 | static const struct file_operations ftrace_graph_fops = { | |
1563 | .open = ftrace_graph_open, | |
1564 | .read = ftrace_graph_read, | |
1565 | .write = ftrace_graph_write, | |
1566 | }; | |
1567 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
1568 | ||
df4fc315 | 1569 | static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) |
5072c59f | 1570 | { |
5072c59f SR |
1571 | struct dentry *entry; |
1572 | ||
5072c59f SR |
1573 | entry = debugfs_create_file("available_filter_functions", 0444, |
1574 | d_tracer, NULL, &ftrace_avail_fops); | |
1575 | if (!entry) | |
1576 | pr_warning("Could not create debugfs " | |
1577 | "'available_filter_functions' entry\n"); | |
1578 | ||
eb9a7bf0 AS |
1579 | entry = debugfs_create_file("failures", 0444, |
1580 | d_tracer, NULL, &ftrace_failures_fops); | |
1581 | if (!entry) | |
1582 | pr_warning("Could not create debugfs 'failures' entry\n"); | |
1583 | ||
5072c59f SR |
1584 | entry = debugfs_create_file("set_ftrace_filter", 0644, d_tracer, |
1585 | NULL, &ftrace_filter_fops); | |
1586 | if (!entry) | |
1587 | pr_warning("Could not create debugfs " | |
1588 | "'set_ftrace_filter' entry\n"); | |
41c52c0d SR |
1589 | |
1590 | entry = debugfs_create_file("set_ftrace_notrace", 0644, d_tracer, | |
1591 | NULL, &ftrace_notrace_fops); | |
1592 | if (!entry) | |
1593 | pr_warning("Could not create debugfs " | |
1594 | "'set_ftrace_notrace' entry\n"); | |
ad90c0e3 | 1595 | |
ea4e2bc4 SR |
1596 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
1597 | entry = debugfs_create_file("set_graph_function", 0444, d_tracer, | |
1598 | NULL, | |
1599 | &ftrace_graph_fops); | |
1600 | if (!entry) | |
1601 | pr_warning("Could not create debugfs " | |
1602 | "'set_graph_function' entry\n"); | |
1603 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
1604 | ||
5072c59f SR |
1605 | return 0; |
1606 | } | |
1607 | ||
31e88909 SR |
1608 | static int ftrace_convert_nops(struct module *mod, |
1609 | unsigned long *start, | |
68bf21aa SR |
1610 | unsigned long *end) |
1611 | { | |
1612 | unsigned long *p; | |
1613 | unsigned long addr; | |
1614 | unsigned long flags; | |
1615 | ||
08f5ac90 | 1616 | mutex_lock(&ftrace_start_lock); |
68bf21aa SR |
1617 | p = start; |
1618 | while (p < end) { | |
1619 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
1620 | /* |
1621 | * Some architecture linkers will pad between | |
1622 | * the different mcount_loc sections of different | |
1623 | * object files to satisfy alignments. | |
1624 | * Skip any NULL pointers. | |
1625 | */ | |
1626 | if (!addr) | |
1627 | continue; | |
68bf21aa | 1628 | ftrace_record_ip(addr); |
68bf21aa SR |
1629 | } |
1630 | ||
08f5ac90 | 1631 | /* disable interrupts to prevent kstop machine */ |
68bf21aa | 1632 | local_irq_save(flags); |
31e88909 | 1633 | ftrace_update_code(mod); |
68bf21aa | 1634 | local_irq_restore(flags); |
08f5ac90 | 1635 | mutex_unlock(&ftrace_start_lock); |
68bf21aa SR |
1636 | |
1637 | return 0; | |
1638 | } | |
1639 | ||
31e88909 SR |
1640 | void ftrace_init_module(struct module *mod, |
1641 | unsigned long *start, unsigned long *end) | |
90d595fe | 1642 | { |
00fd61ae | 1643 | if (ftrace_disabled || start == end) |
fed1939c | 1644 | return; |
31e88909 | 1645 | ftrace_convert_nops(mod, start, end); |
90d595fe SR |
1646 | } |
1647 | ||
68bf21aa SR |
1648 | extern unsigned long __start_mcount_loc[]; |
1649 | extern unsigned long __stop_mcount_loc[]; | |
1650 | ||
1651 | void __init ftrace_init(void) | |
1652 | { | |
1653 | unsigned long count, addr, flags; | |
1654 | int ret; | |
1655 | ||
1656 | /* Keep the ftrace pointer to the stub */ | |
1657 | addr = (unsigned long)ftrace_stub; | |
1658 | ||
1659 | local_irq_save(flags); | |
1660 | ftrace_dyn_arch_init(&addr); | |
1661 | local_irq_restore(flags); | |
1662 | ||
1663 | /* ftrace_dyn_arch_init places the return code in addr */ | |
1664 | if (addr) | |
1665 | goto failed; | |
1666 | ||
1667 | count = __stop_mcount_loc - __start_mcount_loc; | |
1668 | ||
1669 | ret = ftrace_dyn_table_alloc(count); | |
1670 | if (ret) | |
1671 | goto failed; | |
1672 | ||
1673 | last_ftrace_enabled = ftrace_enabled = 1; | |
1674 | ||
31e88909 SR |
1675 | ret = ftrace_convert_nops(NULL, |
1676 | __start_mcount_loc, | |
68bf21aa SR |
1677 | __stop_mcount_loc); |
1678 | ||
1679 | return; | |
1680 | failed: | |
1681 | ftrace_disabled = 1; | |
1682 | } | |
68bf21aa | 1683 | |
3d083395 | 1684 | #else |
0b6e4d56 FW |
1685 | |
1686 | static int __init ftrace_nodyn_init(void) | |
1687 | { | |
1688 | ftrace_enabled = 1; | |
1689 | return 0; | |
1690 | } | |
1691 | device_initcall(ftrace_nodyn_init); | |
1692 | ||
df4fc315 SR |
1693 | static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } |
1694 | static inline void ftrace_startup_enable(int command) { } | |
5a45cfe1 SR |
1695 | /* Keep as macros so we do not need to define the commands */ |
1696 | # define ftrace_startup(command) do { } while (0) | |
1697 | # define ftrace_shutdown(command) do { } while (0) | |
c7aafc54 IM |
1698 | # define ftrace_startup_sysctl() do { } while (0) |
1699 | # define ftrace_shutdown_sysctl() do { } while (0) | |
3d083395 SR |
1700 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
1701 | ||
df4fc315 SR |
1702 | static ssize_t |
1703 | ftrace_pid_read(struct file *file, char __user *ubuf, | |
1704 | size_t cnt, loff_t *ppos) | |
1705 | { | |
1706 | char buf[64]; | |
1707 | int r; | |
1708 | ||
e32d8956 SR |
1709 | if (ftrace_pid_trace == ftrace_swapper_pid) |
1710 | r = sprintf(buf, "swapper tasks\n"); | |
1711 | else if (ftrace_pid_trace) | |
978f3a45 | 1712 | r = sprintf(buf, "%u\n", pid_nr(ftrace_pid_trace)); |
df4fc315 SR |
1713 | else |
1714 | r = sprintf(buf, "no pid\n"); | |
1715 | ||
1716 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
1717 | } | |
1718 | ||
e32d8956 | 1719 | static void clear_ftrace_swapper(void) |
978f3a45 SR |
1720 | { |
1721 | struct task_struct *p; | |
e32d8956 | 1722 | int cpu; |
978f3a45 | 1723 | |
e32d8956 SR |
1724 | get_online_cpus(); |
1725 | for_each_online_cpu(cpu) { | |
1726 | p = idle_task(cpu); | |
978f3a45 | 1727 | clear_tsk_trace_trace(p); |
e32d8956 SR |
1728 | } |
1729 | put_online_cpus(); | |
1730 | } | |
978f3a45 | 1731 | |
e32d8956 SR |
1732 | static void set_ftrace_swapper(void) |
1733 | { | |
1734 | struct task_struct *p; | |
1735 | int cpu; | |
1736 | ||
1737 | get_online_cpus(); | |
1738 | for_each_online_cpu(cpu) { | |
1739 | p = idle_task(cpu); | |
1740 | set_tsk_trace_trace(p); | |
1741 | } | |
1742 | put_online_cpus(); | |
978f3a45 SR |
1743 | } |
1744 | ||
e32d8956 SR |
1745 | static void clear_ftrace_pid(struct pid *pid) |
1746 | { | |
1747 | struct task_struct *p; | |
1748 | ||
229c4ef8 | 1749 | rcu_read_lock(); |
e32d8956 SR |
1750 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
1751 | clear_tsk_trace_trace(p); | |
1752 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 ON |
1753 | rcu_read_unlock(); |
1754 | ||
e32d8956 SR |
1755 | put_pid(pid); |
1756 | } | |
1757 | ||
1758 | static void set_ftrace_pid(struct pid *pid) | |
978f3a45 SR |
1759 | { |
1760 | struct task_struct *p; | |
1761 | ||
229c4ef8 | 1762 | rcu_read_lock(); |
978f3a45 SR |
1763 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
1764 | set_tsk_trace_trace(p); | |
1765 | } while_each_pid_task(pid, PIDTYPE_PID, p); | |
229c4ef8 | 1766 | rcu_read_unlock(); |
978f3a45 SR |
1767 | } |
1768 | ||
e32d8956 SR |
1769 | static void clear_ftrace_pid_task(struct pid **pid) |
1770 | { | |
1771 | if (*pid == ftrace_swapper_pid) | |
1772 | clear_ftrace_swapper(); | |
1773 | else | |
1774 | clear_ftrace_pid(*pid); | |
1775 | ||
1776 | *pid = NULL; | |
1777 | } | |
1778 | ||
1779 | static void set_ftrace_pid_task(struct pid *pid) | |
1780 | { | |
1781 | if (pid == ftrace_swapper_pid) | |
1782 | set_ftrace_swapper(); | |
1783 | else | |
1784 | set_ftrace_pid(pid); | |
1785 | } | |
1786 | ||
df4fc315 SR |
1787 | static ssize_t |
1788 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
1789 | size_t cnt, loff_t *ppos) | |
1790 | { | |
978f3a45 | 1791 | struct pid *pid; |
df4fc315 SR |
1792 | char buf[64]; |
1793 | long val; | |
1794 | int ret; | |
1795 | ||
1796 | if (cnt >= sizeof(buf)) | |
1797 | return -EINVAL; | |
1798 | ||
1799 | if (copy_from_user(&buf, ubuf, cnt)) | |
1800 | return -EFAULT; | |
1801 | ||
1802 | buf[cnt] = 0; | |
1803 | ||
1804 | ret = strict_strtol(buf, 10, &val); | |
1805 | if (ret < 0) | |
1806 | return ret; | |
1807 | ||
1808 | mutex_lock(&ftrace_start_lock); | |
978f3a45 | 1809 | if (val < 0) { |
df4fc315 | 1810 | /* disable pid tracing */ |
978f3a45 | 1811 | if (!ftrace_pid_trace) |
df4fc315 | 1812 | goto out; |
978f3a45 SR |
1813 | |
1814 | clear_ftrace_pid_task(&ftrace_pid_trace); | |
df4fc315 SR |
1815 | |
1816 | } else { | |
e32d8956 SR |
1817 | /* swapper task is special */ |
1818 | if (!val) { | |
1819 | pid = ftrace_swapper_pid; | |
1820 | if (pid == ftrace_pid_trace) | |
1821 | goto out; | |
1822 | } else { | |
1823 | pid = find_get_pid(val); | |
df4fc315 | 1824 | |
e32d8956 SR |
1825 | if (pid == ftrace_pid_trace) { |
1826 | put_pid(pid); | |
1827 | goto out; | |
1828 | } | |
0ef8cde5 | 1829 | } |
0ef8cde5 | 1830 | |
978f3a45 SR |
1831 | if (ftrace_pid_trace) |
1832 | clear_ftrace_pid_task(&ftrace_pid_trace); | |
1833 | ||
1834 | if (!pid) | |
1835 | goto out; | |
1836 | ||
1837 | ftrace_pid_trace = pid; | |
1838 | ||
1839 | set_ftrace_pid_task(ftrace_pid_trace); | |
df4fc315 SR |
1840 | } |
1841 | ||
1842 | /* update the function call */ | |
1843 | ftrace_update_pid_func(); | |
1844 | ftrace_startup_enable(0); | |
1845 | ||
1846 | out: | |
1847 | mutex_unlock(&ftrace_start_lock); | |
1848 | ||
1849 | return cnt; | |
1850 | } | |
1851 | ||
1852 | static struct file_operations ftrace_pid_fops = { | |
1853 | .read = ftrace_pid_read, | |
1854 | .write = ftrace_pid_write, | |
1855 | }; | |
1856 | ||
1857 | static __init int ftrace_init_debugfs(void) | |
1858 | { | |
1859 | struct dentry *d_tracer; | |
1860 | struct dentry *entry; | |
1861 | ||
1862 | d_tracer = tracing_init_dentry(); | |
1863 | if (!d_tracer) | |
1864 | return 0; | |
1865 | ||
1866 | ftrace_init_dyn_debugfs(d_tracer); | |
1867 | ||
1868 | entry = debugfs_create_file("set_ftrace_pid", 0644, d_tracer, | |
1869 | NULL, &ftrace_pid_fops); | |
1870 | if (!entry) | |
1871 | pr_warning("Could not create debugfs " | |
1872 | "'set_ftrace_pid' entry\n"); | |
1873 | return 0; | |
1874 | } | |
1875 | ||
1876 | fs_initcall(ftrace_init_debugfs); | |
1877 | ||
a2bb6a3d | 1878 | /** |
81adbdc0 | 1879 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
1880 | * |
1881 | * This function should be used by panic code. It stops ftrace | |
1882 | * but in a not so nice way. If you need to simply kill ftrace | |
1883 | * from a non-atomic section, use ftrace_kill. | |
1884 | */ | |
81adbdc0 | 1885 | void ftrace_kill(void) |
a2bb6a3d SR |
1886 | { |
1887 | ftrace_disabled = 1; | |
1888 | ftrace_enabled = 0; | |
a2bb6a3d SR |
1889 | clear_ftrace_function(); |
1890 | } | |
1891 | ||
16444a8a | 1892 | /** |
3d083395 SR |
1893 | * register_ftrace_function - register a function for profiling |
1894 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 1895 | * |
3d083395 SR |
1896 | * Register a function to be called by all functions in the |
1897 | * kernel. | |
1898 | * | |
1899 | * Note: @ops->func and all the functions it calls must be labeled | |
1900 | * with "notrace", otherwise it will go into a | |
1901 | * recursive loop. | |
16444a8a | 1902 | */ |
3d083395 | 1903 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 1904 | { |
b0fc494f SR |
1905 | int ret; |
1906 | ||
4eebcc81 SR |
1907 | if (unlikely(ftrace_disabled)) |
1908 | return -1; | |
1909 | ||
b0fc494f | 1910 | mutex_lock(&ftrace_sysctl_lock); |
e7d3737e | 1911 | |
b0fc494f | 1912 | ret = __register_ftrace_function(ops); |
5a45cfe1 | 1913 | ftrace_startup(0); |
b0fc494f | 1914 | |
e7d3737e | 1915 | mutex_unlock(&ftrace_sysctl_lock); |
b0fc494f | 1916 | return ret; |
3d083395 SR |
1917 | } |
1918 | ||
1919 | /** | |
32632920 | 1920 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
1921 | * @ops - ops structure that holds the function to unregister |
1922 | * | |
1923 | * Unregister a function that was added to be called by ftrace profiling. | |
1924 | */ | |
1925 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
1926 | { | |
1927 | int ret; | |
1928 | ||
b0fc494f | 1929 | mutex_lock(&ftrace_sysctl_lock); |
3d083395 | 1930 | ret = __unregister_ftrace_function(ops); |
5a45cfe1 | 1931 | ftrace_shutdown(0); |
b0fc494f SR |
1932 | mutex_unlock(&ftrace_sysctl_lock); |
1933 | ||
1934 | return ret; | |
1935 | } | |
1936 | ||
e309b41d | 1937 | int |
b0fc494f | 1938 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
5072c59f | 1939 | struct file *file, void __user *buffer, size_t *lenp, |
b0fc494f SR |
1940 | loff_t *ppos) |
1941 | { | |
1942 | int ret; | |
1943 | ||
4eebcc81 SR |
1944 | if (unlikely(ftrace_disabled)) |
1945 | return -ENODEV; | |
1946 | ||
b0fc494f SR |
1947 | mutex_lock(&ftrace_sysctl_lock); |
1948 | ||
5072c59f | 1949 | ret = proc_dointvec(table, write, file, buffer, lenp, ppos); |
b0fc494f SR |
1950 | |
1951 | if (ret || !write || (last_ftrace_enabled == ftrace_enabled)) | |
1952 | goto out; | |
1953 | ||
1954 | last_ftrace_enabled = ftrace_enabled; | |
1955 | ||
1956 | if (ftrace_enabled) { | |
1957 | ||
1958 | ftrace_startup_sysctl(); | |
1959 | ||
1960 | /* we are starting ftrace again */ | |
1961 | if (ftrace_list != &ftrace_list_end) { | |
1962 | if (ftrace_list->next == &ftrace_list_end) | |
1963 | ftrace_trace_function = ftrace_list->func; | |
1964 | else | |
1965 | ftrace_trace_function = ftrace_list_func; | |
1966 | } | |
1967 | ||
1968 | } else { | |
1969 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
1970 | ftrace_trace_function = ftrace_stub; | |
1971 | ||
1972 | ftrace_shutdown_sysctl(); | |
1973 | } | |
1974 | ||
1975 | out: | |
1976 | mutex_unlock(&ftrace_sysctl_lock); | |
3d083395 | 1977 | return ret; |
16444a8a | 1978 | } |
f17845e5 | 1979 | |
fb52607a | 1980 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 1981 | |
287b6e68 | 1982 | static atomic_t ftrace_graph_active; |
4a2b8dda | 1983 | static struct notifier_block ftrace_suspend_notifier; |
e7d3737e | 1984 | |
e49dc19c SR |
1985 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
1986 | { | |
1987 | return 0; | |
1988 | } | |
1989 | ||
287b6e68 FW |
1990 | /* The callbacks that hook a function */ |
1991 | trace_func_graph_ret_t ftrace_graph_return = | |
1992 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 1993 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
1994 | |
1995 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
1996 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
1997 | { | |
1998 | int i; | |
1999 | int ret = 0; | |
2000 | unsigned long flags; | |
2001 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; | |
2002 | struct task_struct *g, *t; | |
2003 | ||
2004 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
2005 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
2006 | * sizeof(struct ftrace_ret_stack), | |
2007 | GFP_KERNEL); | |
2008 | if (!ret_stack_list[i]) { | |
2009 | start = 0; | |
2010 | end = i; | |
2011 | ret = -ENOMEM; | |
2012 | goto free; | |
2013 | } | |
2014 | } | |
2015 | ||
2016 | read_lock_irqsave(&tasklist_lock, flags); | |
2017 | do_each_thread(g, t) { | |
2018 | if (start == end) { | |
2019 | ret = -EAGAIN; | |
2020 | goto unlock; | |
2021 | } | |
2022 | ||
2023 | if (t->ret_stack == NULL) { | |
f201ae23 | 2024 | t->curr_ret_stack = -1; |
48d68b20 FW |
2025 | /* Make sure IRQs see the -1 first: */ |
2026 | barrier(); | |
2027 | t->ret_stack = ret_stack_list[start++]; | |
380c4b14 | 2028 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 FW |
2029 | atomic_set(&t->trace_overrun, 0); |
2030 | } | |
2031 | } while_each_thread(g, t); | |
2032 | ||
2033 | unlock: | |
2034 | read_unlock_irqrestore(&tasklist_lock, flags); | |
2035 | free: | |
2036 | for (i = start; i < end; i++) | |
2037 | kfree(ret_stack_list[i]); | |
2038 | return ret; | |
2039 | } | |
2040 | ||
2041 | /* Allocate a return stack for each task */ | |
fb52607a | 2042 | static int start_graph_tracing(void) |
f201ae23 FW |
2043 | { |
2044 | struct ftrace_ret_stack **ret_stack_list; | |
2045 | int ret; | |
2046 | ||
2047 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
2048 | sizeof(struct ftrace_ret_stack *), | |
2049 | GFP_KERNEL); | |
2050 | ||
2051 | if (!ret_stack_list) | |
2052 | return -ENOMEM; | |
2053 | ||
2054 | do { | |
2055 | ret = alloc_retstack_tasklist(ret_stack_list); | |
2056 | } while (ret == -EAGAIN); | |
2057 | ||
2058 | kfree(ret_stack_list); | |
2059 | return ret; | |
2060 | } | |
2061 | ||
4a2b8dda FW |
2062 | /* |
2063 | * Hibernation protection. | |
2064 | * The state of the current task is too much unstable during | |
2065 | * suspend/restore to disk. We want to protect against that. | |
2066 | */ | |
2067 | static int | |
2068 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, | |
2069 | void *unused) | |
2070 | { | |
2071 | switch (state) { | |
2072 | case PM_HIBERNATION_PREPARE: | |
2073 | pause_graph_tracing(); | |
2074 | break; | |
2075 | ||
2076 | case PM_POST_HIBERNATION: | |
2077 | unpause_graph_tracing(); | |
2078 | break; | |
2079 | } | |
2080 | return NOTIFY_DONE; | |
2081 | } | |
2082 | ||
287b6e68 FW |
2083 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
2084 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 2085 | { |
e7d3737e FW |
2086 | int ret = 0; |
2087 | ||
2088 | mutex_lock(&ftrace_sysctl_lock); | |
2089 | ||
4a2b8dda FW |
2090 | ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call; |
2091 | register_pm_notifier(&ftrace_suspend_notifier); | |
2092 | ||
287b6e68 | 2093 | atomic_inc(&ftrace_graph_active); |
fb52607a | 2094 | ret = start_graph_tracing(); |
f201ae23 | 2095 | if (ret) { |
287b6e68 | 2096 | atomic_dec(&ftrace_graph_active); |
f201ae23 FW |
2097 | goto out; |
2098 | } | |
e53a6319 | 2099 | |
287b6e68 FW |
2100 | ftrace_graph_return = retfunc; |
2101 | ftrace_graph_entry = entryfunc; | |
e53a6319 | 2102 | |
5a45cfe1 | 2103 | ftrace_startup(FTRACE_START_FUNC_RET); |
e7d3737e FW |
2104 | |
2105 | out: | |
2106 | mutex_unlock(&ftrace_sysctl_lock); | |
2107 | return ret; | |
15e6cb36 FW |
2108 | } |
2109 | ||
fb52607a | 2110 | void unregister_ftrace_graph(void) |
15e6cb36 | 2111 | { |
e7d3737e FW |
2112 | mutex_lock(&ftrace_sysctl_lock); |
2113 | ||
287b6e68 FW |
2114 | atomic_dec(&ftrace_graph_active); |
2115 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 2116 | ftrace_graph_entry = ftrace_graph_entry_stub; |
5a45cfe1 | 2117 | ftrace_shutdown(FTRACE_STOP_FUNC_RET); |
4a2b8dda | 2118 | unregister_pm_notifier(&ftrace_suspend_notifier); |
e7d3737e FW |
2119 | |
2120 | mutex_unlock(&ftrace_sysctl_lock); | |
15e6cb36 | 2121 | } |
f201ae23 FW |
2122 | |
2123 | /* Allocate a return stack for newly created task */ | |
fb52607a | 2124 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 2125 | { |
287b6e68 | 2126 | if (atomic_read(&ftrace_graph_active)) { |
f201ae23 FW |
2127 | t->ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH |
2128 | * sizeof(struct ftrace_ret_stack), | |
2129 | GFP_KERNEL); | |
2130 | if (!t->ret_stack) | |
2131 | return; | |
2132 | t->curr_ret_stack = -1; | |
380c4b14 | 2133 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 FW |
2134 | atomic_set(&t->trace_overrun, 0); |
2135 | } else | |
2136 | t->ret_stack = NULL; | |
2137 | } | |
2138 | ||
fb52607a | 2139 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 2140 | { |
eae849ca FW |
2141 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
2142 | ||
f201ae23 | 2143 | t->ret_stack = NULL; |
eae849ca FW |
2144 | /* NULL must become visible to IRQs before we free it: */ |
2145 | barrier(); | |
2146 | ||
2147 | kfree(ret_stack); | |
f201ae23 | 2148 | } |
14a866c5 SR |
2149 | |
2150 | void ftrace_graph_stop(void) | |
2151 | { | |
2152 | ftrace_stop(); | |
2153 | } | |
15e6cb36 FW |
2154 | #endif |
2155 |