Commit | Line | Data |
---|---|---|
413d37d1 MH |
1 | /* |
2 | * kprobe based kernel tracer | |
3 | * | |
4 | * Created by Masami Hiramatsu <mhiramat@redhat.com> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License | |
16 | * along with this program; if not, write to the Free Software | |
17 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
18 | */ | |
19 | ||
20 | #include <linux/module.h> | |
21 | #include <linux/uaccess.h> | |
22 | #include <linux/kprobes.h> | |
23 | #include <linux/seq_file.h> | |
24 | #include <linux/slab.h> | |
25 | #include <linux/smp.h> | |
26 | #include <linux/debugfs.h> | |
27 | #include <linux/types.h> | |
28 | #include <linux/string.h> | |
29 | #include <linux/ctype.h> | |
30 | #include <linux/ptrace.h> | |
31 | ||
32 | #include "trace.h" | |
33 | #include "trace_output.h" | |
34 | ||
a82378d8 | 35 | #define MAX_TRACE_ARGS 128 |
413d37d1 | 36 | #define MAX_ARGSTR_LEN 63 |
4263565d | 37 | #define MAX_EVENT_NAME_LEN 64 |
413d37d1 MH |
38 | |
39 | /* currently, trace_kprobe only supports X86. */ | |
40 | ||
41 | struct fetch_func { | |
42 | unsigned long (*func)(struct pt_regs *, void *); | |
43 | void *data; | |
44 | }; | |
45 | ||
46 | static __kprobes unsigned long call_fetch(struct fetch_func *f, | |
47 | struct pt_regs *regs) | |
48 | { | |
49 | return f->func(regs, f->data); | |
50 | } | |
51 | ||
52 | /* fetch handlers */ | |
53 | static __kprobes unsigned long fetch_register(struct pt_regs *regs, | |
54 | void *offset) | |
55 | { | |
56 | return regs_get_register(regs, (unsigned int)((unsigned long)offset)); | |
57 | } | |
58 | ||
59 | static __kprobes unsigned long fetch_stack(struct pt_regs *regs, | |
60 | void *num) | |
61 | { | |
62 | return regs_get_kernel_stack_nth(regs, | |
63 | (unsigned int)((unsigned long)num)); | |
64 | } | |
65 | ||
66 | static __kprobes unsigned long fetch_memory(struct pt_regs *regs, void *addr) | |
67 | { | |
68 | unsigned long retval; | |
69 | ||
70 | if (probe_kernel_address(addr, retval)) | |
71 | return 0; | |
72 | return retval; | |
73 | } | |
74 | ||
75 | static __kprobes unsigned long fetch_argument(struct pt_regs *regs, void *num) | |
76 | { | |
77 | return regs_get_argument_nth(regs, (unsigned int)((unsigned long)num)); | |
78 | } | |
79 | ||
80 | static __kprobes unsigned long fetch_retvalue(struct pt_regs *regs, | |
81 | void *dummy) | |
82 | { | |
83 | return regs_return_value(regs); | |
84 | } | |
85 | ||
86 | static __kprobes unsigned long fetch_ip(struct pt_regs *regs, void *dummy) | |
87 | { | |
88 | return instruction_pointer(regs); | |
89 | } | |
90 | ||
91 | static __kprobes unsigned long fetch_stack_address(struct pt_regs *regs, | |
92 | void *dummy) | |
93 | { | |
94 | return kernel_stack_pointer(regs); | |
95 | } | |
96 | ||
97 | /* Memory fetching by symbol */ | |
98 | struct symbol_cache { | |
99 | char *symbol; | |
100 | long offset; | |
101 | unsigned long addr; | |
102 | }; | |
103 | ||
104 | static unsigned long update_symbol_cache(struct symbol_cache *sc) | |
105 | { | |
106 | sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol); | |
107 | if (sc->addr) | |
108 | sc->addr += sc->offset; | |
109 | return sc->addr; | |
110 | } | |
111 | ||
112 | static void free_symbol_cache(struct symbol_cache *sc) | |
113 | { | |
114 | kfree(sc->symbol); | |
115 | kfree(sc); | |
116 | } | |
117 | ||
118 | static struct symbol_cache *alloc_symbol_cache(const char *sym, long offset) | |
119 | { | |
120 | struct symbol_cache *sc; | |
121 | ||
122 | if (!sym || strlen(sym) == 0) | |
123 | return NULL; | |
124 | sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL); | |
125 | if (!sc) | |
126 | return NULL; | |
127 | ||
128 | sc->symbol = kstrdup(sym, GFP_KERNEL); | |
129 | if (!sc->symbol) { | |
130 | kfree(sc); | |
131 | return NULL; | |
132 | } | |
133 | sc->offset = offset; | |
134 | ||
135 | update_symbol_cache(sc); | |
136 | return sc; | |
137 | } | |
138 | ||
139 | static __kprobes unsigned long fetch_symbol(struct pt_regs *regs, void *data) | |
140 | { | |
141 | struct symbol_cache *sc = data; | |
142 | ||
143 | if (sc->addr) | |
144 | return fetch_memory(regs, (void *)sc->addr); | |
145 | else | |
146 | return 0; | |
147 | } | |
148 | ||
149 | /* Special indirect memory access interface */ | |
150 | struct indirect_fetch_data { | |
151 | struct fetch_func orig; | |
152 | long offset; | |
153 | }; | |
154 | ||
155 | static __kprobes unsigned long fetch_indirect(struct pt_regs *regs, void *data) | |
156 | { | |
157 | struct indirect_fetch_data *ind = data; | |
158 | unsigned long addr; | |
159 | ||
160 | addr = call_fetch(&ind->orig, regs); | |
161 | if (addr) { | |
162 | addr += ind->offset; | |
163 | return fetch_memory(regs, (void *)addr); | |
164 | } else | |
165 | return 0; | |
166 | } | |
167 | ||
168 | static __kprobes void free_indirect_fetch_data(struct indirect_fetch_data *data) | |
169 | { | |
170 | if (data->orig.func == fetch_indirect) | |
171 | free_indirect_fetch_data(data->orig.data); | |
172 | else if (data->orig.func == fetch_symbol) | |
173 | free_symbol_cache(data->orig.data); | |
174 | kfree(data); | |
175 | } | |
176 | ||
177 | /** | |
178 | * kprobe_trace_core | |
179 | */ | |
180 | ||
181 | struct trace_probe { | |
182 | struct list_head list; | |
4a846b44 | 183 | struct kretprobe rp; /* Use rp.kp for kprobe use */ |
cd7e7bd5 | 184 | unsigned long nhit; |
413d37d1 | 185 | const char *symbol; /* symbol name */ |
413d37d1 | 186 | struct ftrace_event_call call; |
ff50d991 | 187 | struct trace_event event; |
a82378d8 MH |
188 | unsigned int nr_args; |
189 | struct fetch_func args[]; | |
413d37d1 MH |
190 | }; |
191 | ||
a82378d8 MH |
192 | #define SIZEOF_TRACE_PROBE(n) \ |
193 | (offsetof(struct trace_probe, args) + \ | |
194 | (sizeof(struct fetch_func) * (n))) | |
195 | ||
413d37d1 MH |
196 | static int kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs); |
197 | static int kretprobe_trace_func(struct kretprobe_instance *ri, | |
198 | struct pt_regs *regs); | |
199 | ||
200 | static __kprobes int probe_is_return(struct trace_probe *tp) | |
201 | { | |
4a846b44 | 202 | return tp->rp.handler != NULL; |
413d37d1 MH |
203 | } |
204 | ||
205 | static __kprobes const char *probe_symbol(struct trace_probe *tp) | |
206 | { | |
207 | return tp->symbol ? tp->symbol : "unknown"; | |
208 | } | |
209 | ||
30a7e073 | 210 | static int probe_arg_string(char *buf, size_t n, struct fetch_func *ff) |
413d37d1 MH |
211 | { |
212 | int ret = -EINVAL; | |
213 | ||
214 | if (ff->func == fetch_argument) | |
215 | ret = snprintf(buf, n, "a%lu", (unsigned long)ff->data); | |
216 | else if (ff->func == fetch_register) { | |
217 | const char *name; | |
218 | name = regs_query_register_name((unsigned int)((long)ff->data)); | |
219 | ret = snprintf(buf, n, "%%%s", name); | |
220 | } else if (ff->func == fetch_stack) | |
221 | ret = snprintf(buf, n, "s%lu", (unsigned long)ff->data); | |
222 | else if (ff->func == fetch_memory) | |
223 | ret = snprintf(buf, n, "@0x%p", ff->data); | |
224 | else if (ff->func == fetch_symbol) { | |
225 | struct symbol_cache *sc = ff->data; | |
226 | ret = snprintf(buf, n, "@%s%+ld", sc->symbol, sc->offset); | |
227 | } else if (ff->func == fetch_retvalue) | |
228 | ret = snprintf(buf, n, "rv"); | |
229 | else if (ff->func == fetch_ip) | |
230 | ret = snprintf(buf, n, "ra"); | |
231 | else if (ff->func == fetch_stack_address) | |
232 | ret = snprintf(buf, n, "sa"); | |
233 | else if (ff->func == fetch_indirect) { | |
234 | struct indirect_fetch_data *id = ff->data; | |
235 | size_t l = 0; | |
236 | ret = snprintf(buf, n, "%+ld(", id->offset); | |
237 | if (ret >= n) | |
238 | goto end; | |
239 | l += ret; | |
30a7e073 | 240 | ret = probe_arg_string(buf + l, n - l, &id->orig); |
413d37d1 MH |
241 | if (ret < 0) |
242 | goto end; | |
243 | l += ret; | |
244 | ret = snprintf(buf + l, n - l, ")"); | |
245 | ret += l; | |
246 | } | |
247 | end: | |
248 | if (ret >= n) | |
249 | return -ENOSPC; | |
250 | return ret; | |
251 | } | |
252 | ||
253 | static int register_probe_event(struct trace_probe *tp); | |
254 | static void unregister_probe_event(struct trace_probe *tp); | |
255 | ||
256 | static DEFINE_MUTEX(probe_lock); | |
257 | static LIST_HEAD(probe_list); | |
258 | ||
4a846b44 MH |
259 | /* |
260 | * Allocate new trace_probe and initialize it (including kprobes). | |
261 | */ | |
262 | static struct trace_probe *alloc_trace_probe(const char *event, | |
263 | void *addr, | |
264 | const char *symbol, | |
265 | unsigned long offs, | |
266 | int nargs, int is_return) | |
413d37d1 MH |
267 | { |
268 | struct trace_probe *tp; | |
269 | ||
a82378d8 | 270 | tp = kzalloc(SIZEOF_TRACE_PROBE(nargs), GFP_KERNEL); |
413d37d1 MH |
271 | if (!tp) |
272 | return ERR_PTR(-ENOMEM); | |
273 | ||
274 | if (symbol) { | |
275 | tp->symbol = kstrdup(symbol, GFP_KERNEL); | |
276 | if (!tp->symbol) | |
277 | goto error; | |
4a846b44 MH |
278 | tp->rp.kp.symbol_name = tp->symbol; |
279 | tp->rp.kp.offset = offs; | |
280 | } else | |
281 | tp->rp.kp.addr = addr; | |
282 | ||
283 | if (is_return) | |
284 | tp->rp.handler = kretprobe_trace_func; | |
285 | else | |
286 | tp->rp.kp.pre_handler = kprobe_trace_func; | |
287 | ||
4263565d MH |
288 | if (!event) |
289 | goto error; | |
290 | tp->call.name = kstrdup(event, GFP_KERNEL); | |
291 | if (!tp->call.name) | |
292 | goto error; | |
413d37d1 MH |
293 | |
294 | INIT_LIST_HEAD(&tp->list); | |
295 | return tp; | |
296 | error: | |
297 | kfree(tp->symbol); | |
298 | kfree(tp); | |
299 | return ERR_PTR(-ENOMEM); | |
300 | } | |
301 | ||
302 | static void free_trace_probe(struct trace_probe *tp) | |
303 | { | |
304 | int i; | |
305 | ||
306 | for (i = 0; i < tp->nr_args; i++) | |
307 | if (tp->args[i].func == fetch_symbol) | |
308 | free_symbol_cache(tp->args[i].data); | |
309 | else if (tp->args[i].func == fetch_indirect) | |
310 | free_indirect_fetch_data(tp->args[i].data); | |
311 | ||
312 | kfree(tp->call.name); | |
313 | kfree(tp->symbol); | |
314 | kfree(tp); | |
315 | } | |
316 | ||
317 | static struct trace_probe *find_probe_event(const char *event) | |
318 | { | |
319 | struct trace_probe *tp; | |
320 | ||
321 | list_for_each_entry(tp, &probe_list, list) | |
4263565d | 322 | if (!strcmp(tp->call.name, event)) |
413d37d1 MH |
323 | return tp; |
324 | return NULL; | |
325 | } | |
326 | ||
327 | static void __unregister_trace_probe(struct trace_probe *tp) | |
328 | { | |
329 | if (probe_is_return(tp)) | |
330 | unregister_kretprobe(&tp->rp); | |
331 | else | |
4a846b44 | 332 | unregister_kprobe(&tp->rp.kp); |
413d37d1 MH |
333 | } |
334 | ||
335 | /* Unregister a trace_probe and probe_event: call with locking probe_lock */ | |
336 | static void unregister_trace_probe(struct trace_probe *tp) | |
337 | { | |
4263565d | 338 | unregister_probe_event(tp); |
413d37d1 MH |
339 | __unregister_trace_probe(tp); |
340 | list_del(&tp->list); | |
341 | } | |
342 | ||
343 | /* Register a trace_probe and probe_event */ | |
344 | static int register_trace_probe(struct trace_probe *tp) | |
345 | { | |
346 | struct trace_probe *old_tp; | |
347 | int ret; | |
348 | ||
349 | mutex_lock(&probe_lock); | |
350 | ||
351 | if (probe_is_return(tp)) | |
352 | ret = register_kretprobe(&tp->rp); | |
353 | else | |
4a846b44 | 354 | ret = register_kprobe(&tp->rp.kp); |
413d37d1 MH |
355 | |
356 | if (ret) { | |
357 | pr_warning("Could not insert probe(%d)\n", ret); | |
358 | if (ret == -EILSEQ) { | |
359 | pr_warning("Probing address(0x%p) is not an " | |
360 | "instruction boundary.\n", | |
4a846b44 | 361 | tp->rp.kp.addr); |
413d37d1 MH |
362 | ret = -EINVAL; |
363 | } | |
364 | goto end; | |
365 | } | |
366 | /* register as an event */ | |
4263565d MH |
367 | old_tp = find_probe_event(tp->call.name); |
368 | if (old_tp) { | |
369 | /* delete old event */ | |
370 | unregister_trace_probe(old_tp); | |
371 | free_trace_probe(old_tp); | |
372 | } | |
373 | ret = register_probe_event(tp); | |
374 | if (ret) { | |
375 | pr_warning("Faild to register probe event(%d)\n", ret); | |
376 | __unregister_trace_probe(tp); | |
413d37d1 MH |
377 | } |
378 | list_add_tail(&tp->list, &probe_list); | |
379 | end: | |
380 | mutex_unlock(&probe_lock); | |
381 | return ret; | |
382 | } | |
383 | ||
384 | /* Split symbol and offset. */ | |
2fba0c88 | 385 | static int split_symbol_offset(char *symbol, unsigned long *offset) |
413d37d1 MH |
386 | { |
387 | char *tmp; | |
388 | int ret; | |
389 | ||
390 | if (!offset) | |
391 | return -EINVAL; | |
392 | ||
393 | tmp = strchr(symbol, '+'); | |
413d37d1 MH |
394 | if (tmp) { |
395 | /* skip sign because strict_strtol doesn't accept '+' */ | |
2fba0c88 | 396 | ret = strict_strtoul(tmp + 1, 0, offset); |
413d37d1 MH |
397 | if (ret) |
398 | return ret; | |
413d37d1 MH |
399 | *tmp = '\0'; |
400 | } else | |
401 | *offset = 0; | |
402 | return 0; | |
403 | } | |
404 | ||
405 | #define PARAM_MAX_ARGS 16 | |
406 | #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long)) | |
407 | ||
30a7e073 | 408 | static int parse_probe_arg(char *arg, struct fetch_func *ff, int is_return) |
413d37d1 MH |
409 | { |
410 | int ret = 0; | |
411 | unsigned long param; | |
412 | long offset; | |
413 | char *tmp; | |
414 | ||
415 | switch (arg[0]) { | |
416 | case 'a': /* argument */ | |
417 | ret = strict_strtoul(arg + 1, 10, ¶m); | |
418 | if (ret || param > PARAM_MAX_ARGS) | |
419 | ret = -EINVAL; | |
420 | else { | |
421 | ff->func = fetch_argument; | |
422 | ff->data = (void *)param; | |
423 | } | |
424 | break; | |
425 | case 'r': /* retval or retaddr */ | |
426 | if (is_return && arg[1] == 'v') { | |
427 | ff->func = fetch_retvalue; | |
428 | ff->data = NULL; | |
429 | } else if (is_return && arg[1] == 'a') { | |
430 | ff->func = fetch_ip; | |
431 | ff->data = NULL; | |
432 | } else | |
433 | ret = -EINVAL; | |
434 | break; | |
435 | case '%': /* named register */ | |
436 | ret = regs_query_register_offset(arg + 1); | |
437 | if (ret >= 0) { | |
438 | ff->func = fetch_register; | |
439 | ff->data = (void *)(unsigned long)ret; | |
440 | ret = 0; | |
441 | } | |
442 | break; | |
443 | case 's': /* stack */ | |
444 | if (arg[1] == 'a') { | |
445 | ff->func = fetch_stack_address; | |
446 | ff->data = NULL; | |
447 | } else { | |
448 | ret = strict_strtoul(arg + 1, 10, ¶m); | |
449 | if (ret || param > PARAM_MAX_STACK) | |
450 | ret = -EINVAL; | |
451 | else { | |
452 | ff->func = fetch_stack; | |
453 | ff->data = (void *)param; | |
454 | } | |
455 | } | |
456 | break; | |
457 | case '@': /* memory or symbol */ | |
458 | if (isdigit(arg[1])) { | |
459 | ret = strict_strtoul(arg + 1, 0, ¶m); | |
460 | if (ret) | |
461 | break; | |
462 | ff->func = fetch_memory; | |
463 | ff->data = (void *)param; | |
464 | } else { | |
465 | ret = split_symbol_offset(arg + 1, &offset); | |
466 | if (ret) | |
467 | break; | |
468 | ff->data = alloc_symbol_cache(arg + 1, | |
469 | offset); | |
470 | if (ff->data) | |
471 | ff->func = fetch_symbol; | |
472 | else | |
473 | ret = -EINVAL; | |
474 | } | |
475 | break; | |
476 | case '+': /* indirect memory */ | |
477 | case '-': | |
478 | tmp = strchr(arg, '('); | |
479 | if (!tmp) { | |
480 | ret = -EINVAL; | |
481 | break; | |
482 | } | |
483 | *tmp = '\0'; | |
484 | ret = strict_strtol(arg + 1, 0, &offset); | |
485 | if (ret) | |
486 | break; | |
487 | if (arg[0] == '-') | |
488 | offset = -offset; | |
489 | arg = tmp + 1; | |
490 | tmp = strrchr(arg, ')'); | |
491 | if (tmp) { | |
492 | struct indirect_fetch_data *id; | |
493 | *tmp = '\0'; | |
494 | id = kzalloc(sizeof(struct indirect_fetch_data), | |
495 | GFP_KERNEL); | |
496 | if (!id) | |
497 | return -ENOMEM; | |
498 | id->offset = offset; | |
30a7e073 | 499 | ret = parse_probe_arg(arg, &id->orig, is_return); |
413d37d1 MH |
500 | if (ret) |
501 | kfree(id); | |
502 | else { | |
503 | ff->func = fetch_indirect; | |
504 | ff->data = (void *)id; | |
505 | } | |
506 | } else | |
507 | ret = -EINVAL; | |
508 | break; | |
509 | default: | |
510 | /* TODO: support custom handler */ | |
511 | ret = -EINVAL; | |
512 | } | |
513 | return ret; | |
514 | } | |
515 | ||
516 | static int create_trace_probe(int argc, char **argv) | |
517 | { | |
518 | /* | |
519 | * Argument syntax: | |
2fba0c88 | 520 | * - Add kprobe: p[:EVENT] SYMBOL[+OFFS]|ADDRESS [FETCHARGS] |
413d37d1 MH |
521 | * - Add kretprobe: r[:EVENT] SYMBOL[+0] [FETCHARGS] |
522 | * Fetch args: | |
523 | * aN : fetch Nth of function argument. (N:0-) | |
524 | * rv : fetch return value | |
525 | * ra : fetch return address | |
526 | * sa : fetch stack address | |
527 | * sN : fetch Nth of stack (N:0-) | |
528 | * @ADDR : fetch memory at ADDR (ADDR should be in kernel) | |
529 | * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol) | |
530 | * %REG : fetch register REG | |
531 | * Indirect memory fetch: | |
532 | * +|-offs(ARG) : fetch memory at ARG +|- offs address. | |
533 | */ | |
534 | struct trace_probe *tp; | |
413d37d1 MH |
535 | int i, ret = 0; |
536 | int is_return = 0; | |
537 | char *symbol = NULL, *event = NULL; | |
2fba0c88 | 538 | unsigned long offset = 0; |
413d37d1 | 539 | void *addr = NULL; |
4a846b44 | 540 | char buf[MAX_EVENT_NAME_LEN]; |
413d37d1 MH |
541 | |
542 | if (argc < 2) | |
543 | return -EINVAL; | |
544 | ||
545 | if (argv[0][0] == 'p') | |
546 | is_return = 0; | |
547 | else if (argv[0][0] == 'r') | |
548 | is_return = 1; | |
549 | else | |
550 | return -EINVAL; | |
551 | ||
552 | if (argv[0][1] == ':') { | |
553 | event = &argv[0][2]; | |
554 | if (strlen(event) == 0) { | |
555 | pr_info("Event name is not specifiled\n"); | |
556 | return -EINVAL; | |
557 | } | |
558 | } | |
559 | ||
560 | if (isdigit(argv[1][0])) { | |
561 | if (is_return) | |
562 | return -EINVAL; | |
563 | /* an address specified */ | |
564 | ret = strict_strtoul(&argv[0][2], 0, (unsigned long *)&addr); | |
565 | if (ret) | |
566 | return ret; | |
567 | } else { | |
568 | /* a symbol specified */ | |
569 | symbol = argv[1]; | |
570 | /* TODO: support .init module functions */ | |
571 | ret = split_symbol_offset(symbol, &offset); | |
572 | if (ret) | |
573 | return ret; | |
574 | if (offset && is_return) | |
575 | return -EINVAL; | |
576 | } | |
a82378d8 | 577 | argc -= 2; argv += 2; |
413d37d1 MH |
578 | |
579 | /* setup a probe */ | |
4263565d MH |
580 | if (!event) { |
581 | /* Make a new event name */ | |
4263565d MH |
582 | if (symbol) |
583 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c@%s%+ld", | |
584 | is_return ? 'r' : 'p', symbol, offset); | |
585 | else | |
586 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c@0x%p", | |
587 | is_return ? 'r' : 'p', addr); | |
4a846b44 MH |
588 | event = buf; |
589 | } | |
590 | tp = alloc_trace_probe(event, addr, symbol, offset, argc, is_return); | |
413d37d1 MH |
591 | if (IS_ERR(tp)) |
592 | return PTR_ERR(tp); | |
593 | ||
413d37d1 | 594 | /* parse arguments */ |
a82378d8 MH |
595 | ret = 0; |
596 | for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { | |
413d37d1 MH |
597 | if (strlen(argv[i]) > MAX_ARGSTR_LEN) { |
598 | pr_info("Argument%d(%s) is too long.\n", i, argv[i]); | |
599 | ret = -ENOSPC; | |
600 | goto error; | |
601 | } | |
30a7e073 | 602 | ret = parse_probe_arg(argv[i], &tp->args[i], is_return); |
413d37d1 MH |
603 | if (ret) |
604 | goto error; | |
605 | } | |
606 | tp->nr_args = i; | |
607 | ||
608 | ret = register_trace_probe(tp); | |
609 | if (ret) | |
610 | goto error; | |
611 | return 0; | |
612 | ||
613 | error: | |
614 | free_trace_probe(tp); | |
615 | return ret; | |
616 | } | |
617 | ||
618 | static void cleanup_all_probes(void) | |
619 | { | |
620 | struct trace_probe *tp; | |
621 | ||
622 | mutex_lock(&probe_lock); | |
623 | /* TODO: Use batch unregistration */ | |
624 | while (!list_empty(&probe_list)) { | |
625 | tp = list_entry(probe_list.next, struct trace_probe, list); | |
626 | unregister_trace_probe(tp); | |
627 | free_trace_probe(tp); | |
628 | } | |
629 | mutex_unlock(&probe_lock); | |
630 | } | |
631 | ||
632 | ||
633 | /* Probes listing interfaces */ | |
634 | static void *probes_seq_start(struct seq_file *m, loff_t *pos) | |
635 | { | |
636 | mutex_lock(&probe_lock); | |
637 | return seq_list_start(&probe_list, *pos); | |
638 | } | |
639 | ||
640 | static void *probes_seq_next(struct seq_file *m, void *v, loff_t *pos) | |
641 | { | |
642 | return seq_list_next(v, &probe_list, pos); | |
643 | } | |
644 | ||
645 | static void probes_seq_stop(struct seq_file *m, void *v) | |
646 | { | |
647 | mutex_unlock(&probe_lock); | |
648 | } | |
649 | ||
650 | static int probes_seq_show(struct seq_file *m, void *v) | |
651 | { | |
652 | struct trace_probe *tp = v; | |
653 | int i, ret; | |
654 | char buf[MAX_ARGSTR_LEN + 1]; | |
655 | ||
656 | seq_printf(m, "%c", probe_is_return(tp) ? 'r' : 'p'); | |
4263565d | 657 | seq_printf(m, ":%s", tp->call.name); |
413d37d1 MH |
658 | |
659 | if (tp->symbol) | |
4a846b44 | 660 | seq_printf(m, " %s+%u", probe_symbol(tp), tp->rp.kp.offset); |
413d37d1 | 661 | else |
4a846b44 | 662 | seq_printf(m, " 0x%p", tp->rp.kp.addr); |
413d37d1 MH |
663 | |
664 | for (i = 0; i < tp->nr_args; i++) { | |
30a7e073 | 665 | ret = probe_arg_string(buf, MAX_ARGSTR_LEN, &tp->args[i]); |
413d37d1 MH |
666 | if (ret < 0) { |
667 | pr_warning("Argument%d decoding error(%d).\n", i, ret); | |
668 | return ret; | |
669 | } | |
670 | seq_printf(m, " %s", buf); | |
671 | } | |
672 | seq_printf(m, "\n"); | |
673 | return 0; | |
674 | } | |
675 | ||
676 | static const struct seq_operations probes_seq_op = { | |
677 | .start = probes_seq_start, | |
678 | .next = probes_seq_next, | |
679 | .stop = probes_seq_stop, | |
680 | .show = probes_seq_show | |
681 | }; | |
682 | ||
683 | static int probes_open(struct inode *inode, struct file *file) | |
684 | { | |
685 | if ((file->f_mode & FMODE_WRITE) && | |
686 | (file->f_flags & O_TRUNC)) | |
687 | cleanup_all_probes(); | |
688 | ||
689 | return seq_open(file, &probes_seq_op); | |
690 | } | |
691 | ||
692 | static int command_trace_probe(const char *buf) | |
693 | { | |
694 | char **argv; | |
695 | int argc = 0, ret = 0; | |
696 | ||
697 | argv = argv_split(GFP_KERNEL, buf, &argc); | |
698 | if (!argv) | |
699 | return -ENOMEM; | |
700 | ||
701 | if (argc) | |
702 | ret = create_trace_probe(argc, argv); | |
703 | ||
704 | argv_free(argv); | |
705 | return ret; | |
706 | } | |
707 | ||
708 | #define WRITE_BUFSIZE 128 | |
709 | ||
710 | static ssize_t probes_write(struct file *file, const char __user *buffer, | |
711 | size_t count, loff_t *ppos) | |
712 | { | |
713 | char *kbuf, *tmp; | |
714 | int ret; | |
715 | size_t done; | |
716 | size_t size; | |
717 | ||
718 | kbuf = kmalloc(WRITE_BUFSIZE, GFP_KERNEL); | |
719 | if (!kbuf) | |
720 | return -ENOMEM; | |
721 | ||
722 | ret = done = 0; | |
723 | while (done < count) { | |
724 | size = count - done; | |
725 | if (size >= WRITE_BUFSIZE) | |
726 | size = WRITE_BUFSIZE - 1; | |
727 | if (copy_from_user(kbuf, buffer + done, size)) { | |
728 | ret = -EFAULT; | |
729 | goto out; | |
730 | } | |
731 | kbuf[size] = '\0'; | |
732 | tmp = strchr(kbuf, '\n'); | |
733 | if (tmp) { | |
734 | *tmp = '\0'; | |
735 | size = tmp - kbuf + 1; | |
736 | } else if (done + size < count) { | |
737 | pr_warning("Line length is too long: " | |
738 | "Should be less than %d.", WRITE_BUFSIZE); | |
739 | ret = -EINVAL; | |
740 | goto out; | |
741 | } | |
742 | done += size; | |
743 | /* Remove comments */ | |
744 | tmp = strchr(kbuf, '#'); | |
745 | if (tmp) | |
746 | *tmp = '\0'; | |
747 | ||
748 | ret = command_trace_probe(kbuf); | |
749 | if (ret) | |
750 | goto out; | |
751 | } | |
752 | ret = done; | |
753 | out: | |
754 | kfree(kbuf); | |
755 | return ret; | |
756 | } | |
757 | ||
758 | static const struct file_operations kprobe_events_ops = { | |
759 | .owner = THIS_MODULE, | |
760 | .open = probes_open, | |
761 | .read = seq_read, | |
762 | .llseek = seq_lseek, | |
763 | .release = seq_release, | |
764 | .write = probes_write, | |
765 | }; | |
766 | ||
cd7e7bd5 MH |
767 | /* Probes profiling interfaces */ |
768 | static int probes_profile_seq_show(struct seq_file *m, void *v) | |
769 | { | |
770 | struct trace_probe *tp = v; | |
771 | ||
772 | seq_printf(m, " %-44s %15lu %15lu\n", tp->call.name, tp->nhit, | |
4a846b44 | 773 | tp->rp.kp.nmissed); |
cd7e7bd5 MH |
774 | |
775 | return 0; | |
776 | } | |
777 | ||
778 | static const struct seq_operations profile_seq_op = { | |
779 | .start = probes_seq_start, | |
780 | .next = probes_seq_next, | |
781 | .stop = probes_seq_stop, | |
782 | .show = probes_profile_seq_show | |
783 | }; | |
784 | ||
785 | static int profile_open(struct inode *inode, struct file *file) | |
786 | { | |
787 | return seq_open(file, &profile_seq_op); | |
788 | } | |
789 | ||
790 | static const struct file_operations kprobe_profile_ops = { | |
791 | .owner = THIS_MODULE, | |
792 | .open = profile_open, | |
793 | .read = seq_read, | |
794 | .llseek = seq_lseek, | |
795 | .release = seq_release, | |
796 | }; | |
797 | ||
413d37d1 MH |
798 | /* Kprobe handler */ |
799 | static __kprobes int kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs) | |
800 | { | |
4a846b44 | 801 | struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); |
413d37d1 MH |
802 | struct kprobe_trace_entry *entry; |
803 | struct ring_buffer_event *event; | |
8f8ffe24 | 804 | struct ring_buffer *buffer; |
413d37d1 MH |
805 | int size, i, pc; |
806 | unsigned long irq_flags; | |
4263565d | 807 | struct ftrace_event_call *call = &tp->call; |
413d37d1 | 808 | |
cd7e7bd5 MH |
809 | tp->nhit++; |
810 | ||
413d37d1 MH |
811 | local_save_flags(irq_flags); |
812 | pc = preempt_count(); | |
813 | ||
814 | size = SIZEOF_KPROBE_TRACE_ENTRY(tp->nr_args); | |
815 | ||
8f8ffe24 | 816 | event = trace_current_buffer_lock_reserve(&buffer, call->id, size, |
413d37d1 MH |
817 | irq_flags, pc); |
818 | if (!event) | |
819 | return 0; | |
820 | ||
821 | entry = ring_buffer_event_data(event); | |
822 | entry->nargs = tp->nr_args; | |
823 | entry->ip = (unsigned long)kp->addr; | |
824 | for (i = 0; i < tp->nr_args; i++) | |
825 | entry->args[i] = call_fetch(&tp->args[i], regs); | |
826 | ||
8f8ffe24 FW |
827 | if (!filter_current_check_discard(buffer, call, entry, event)) |
828 | trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc); | |
413d37d1 MH |
829 | return 0; |
830 | } | |
831 | ||
832 | /* Kretprobe handler */ | |
833 | static __kprobes int kretprobe_trace_func(struct kretprobe_instance *ri, | |
834 | struct pt_regs *regs) | |
835 | { | |
836 | struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); | |
837 | struct kretprobe_trace_entry *entry; | |
838 | struct ring_buffer_event *event; | |
8f8ffe24 | 839 | struct ring_buffer *buffer; |
413d37d1 MH |
840 | int size, i, pc; |
841 | unsigned long irq_flags; | |
4263565d | 842 | struct ftrace_event_call *call = &tp->call; |
413d37d1 MH |
843 | |
844 | local_save_flags(irq_flags); | |
845 | pc = preempt_count(); | |
846 | ||
847 | size = SIZEOF_KRETPROBE_TRACE_ENTRY(tp->nr_args); | |
848 | ||
8f8ffe24 | 849 | event = trace_current_buffer_lock_reserve(&buffer, call->id, size, |
413d37d1 MH |
850 | irq_flags, pc); |
851 | if (!event) | |
852 | return 0; | |
853 | ||
854 | entry = ring_buffer_event_data(event); | |
855 | entry->nargs = tp->nr_args; | |
4a846b44 | 856 | entry->func = (unsigned long)tp->rp.kp.addr; |
413d37d1 MH |
857 | entry->ret_ip = (unsigned long)ri->ret_addr; |
858 | for (i = 0; i < tp->nr_args; i++) | |
859 | entry->args[i] = call_fetch(&tp->args[i], regs); | |
860 | ||
8f8ffe24 FW |
861 | if (!filter_current_check_discard(buffer, call, entry, event)) |
862 | trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc); | |
413d37d1 MH |
863 | |
864 | return 0; | |
865 | } | |
866 | ||
867 | /* Event entry printers */ | |
868 | enum print_line_t | |
869 | print_kprobe_event(struct trace_iterator *iter, int flags) | |
870 | { | |
871 | struct kprobe_trace_entry *field; | |
872 | struct trace_seq *s = &iter->seq; | |
873 | int i; | |
874 | ||
ff50d991 | 875 | field = (struct kprobe_trace_entry *)iter->ent; |
413d37d1 MH |
876 | |
877 | if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET)) | |
878 | goto partial; | |
879 | ||
880 | if (!trace_seq_puts(s, ":")) | |
881 | goto partial; | |
882 | ||
883 | for (i = 0; i < field->nargs; i++) | |
884 | if (!trace_seq_printf(s, " 0x%lx", field->args[i])) | |
885 | goto partial; | |
886 | ||
887 | if (!trace_seq_puts(s, "\n")) | |
888 | goto partial; | |
889 | ||
890 | return TRACE_TYPE_HANDLED; | |
891 | partial: | |
892 | return TRACE_TYPE_PARTIAL_LINE; | |
893 | } | |
894 | ||
895 | enum print_line_t | |
896 | print_kretprobe_event(struct trace_iterator *iter, int flags) | |
897 | { | |
898 | struct kretprobe_trace_entry *field; | |
899 | struct trace_seq *s = &iter->seq; | |
900 | int i; | |
901 | ||
ff50d991 | 902 | field = (struct kretprobe_trace_entry *)iter->ent; |
413d37d1 MH |
903 | |
904 | if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET)) | |
905 | goto partial; | |
906 | ||
907 | if (!trace_seq_puts(s, " <- ")) | |
908 | goto partial; | |
909 | ||
910 | if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET)) | |
911 | goto partial; | |
912 | ||
913 | if (!trace_seq_puts(s, ":")) | |
914 | goto partial; | |
915 | ||
916 | for (i = 0; i < field->nargs; i++) | |
917 | if (!trace_seq_printf(s, " 0x%lx", field->args[i])) | |
918 | goto partial; | |
919 | ||
920 | if (!trace_seq_puts(s, "\n")) | |
921 | goto partial; | |
922 | ||
923 | return TRACE_TYPE_HANDLED; | |
924 | partial: | |
925 | return TRACE_TYPE_PARTIAL_LINE; | |
926 | } | |
927 | ||
413d37d1 MH |
928 | static int probe_event_enable(struct ftrace_event_call *call) |
929 | { | |
930 | struct trace_probe *tp = (struct trace_probe *)call->data; | |
931 | ||
932 | if (probe_is_return(tp)) | |
933 | return enable_kretprobe(&tp->rp); | |
934 | else | |
4a846b44 | 935 | return enable_kprobe(&tp->rp.kp); |
413d37d1 MH |
936 | } |
937 | ||
938 | static void probe_event_disable(struct ftrace_event_call *call) | |
939 | { | |
940 | struct trace_probe *tp = (struct trace_probe *)call->data; | |
941 | ||
942 | if (probe_is_return(tp)) | |
943 | disable_kretprobe(&tp->rp); | |
944 | else | |
4a846b44 | 945 | disable_kprobe(&tp->rp.kp); |
413d37d1 MH |
946 | } |
947 | ||
948 | static int probe_event_raw_init(struct ftrace_event_call *event_call) | |
949 | { | |
950 | INIT_LIST_HEAD(&event_call->fields); | |
8f8ffe24 | 951 | |
413d37d1 MH |
952 | return 0; |
953 | } | |
954 | ||
955 | #undef DEFINE_FIELD | |
956 | #define DEFINE_FIELD(type, item, name, is_signed) \ | |
957 | do { \ | |
958 | ret = trace_define_field(event_call, #type, name, \ | |
959 | offsetof(typeof(field), item), \ | |
960 | sizeof(field.item), is_signed, \ | |
961 | FILTER_OTHER); \ | |
962 | if (ret) \ | |
963 | return ret; \ | |
964 | } while (0) | |
965 | ||
966 | static int kprobe_event_define_fields(struct ftrace_event_call *event_call) | |
967 | { | |
968 | int ret, i; | |
969 | struct kprobe_trace_entry field; | |
970 | char buf[MAX_ARGSTR_LEN + 1]; | |
971 | struct trace_probe *tp = (struct trace_probe *)event_call->data; | |
972 | ||
973 | ret = trace_define_common_fields(event_call); | |
974 | if (!ret) | |
975 | return ret; | |
976 | ||
977 | DEFINE_FIELD(unsigned long, ip, "ip", 0); | |
978 | DEFINE_FIELD(int, nargs, "nargs", 1); | |
979 | for (i = 0; i < tp->nr_args; i++) { | |
980 | /* Set argN as a field */ | |
981 | sprintf(buf, "arg%d", i); | |
982 | DEFINE_FIELD(unsigned long, args[i], buf, 0); | |
983 | /* Set argument string as an alias field */ | |
30a7e073 | 984 | ret = probe_arg_string(buf, MAX_ARGSTR_LEN, &tp->args[i]); |
413d37d1 MH |
985 | if (ret < 0) |
986 | return ret; | |
987 | DEFINE_FIELD(unsigned long, args[i], buf, 0); | |
988 | } | |
989 | return 0; | |
990 | } | |
991 | ||
992 | static int kretprobe_event_define_fields(struct ftrace_event_call *event_call) | |
993 | { | |
994 | int ret, i; | |
995 | struct kretprobe_trace_entry field; | |
996 | char buf[MAX_ARGSTR_LEN + 1]; | |
997 | struct trace_probe *tp = (struct trace_probe *)event_call->data; | |
998 | ||
999 | ret = trace_define_common_fields(event_call); | |
1000 | if (!ret) | |
1001 | return ret; | |
1002 | ||
1003 | DEFINE_FIELD(unsigned long, func, "func", 0); | |
1004 | DEFINE_FIELD(unsigned long, ret_ip, "ret_ip", 0); | |
1005 | DEFINE_FIELD(int, nargs, "nargs", 1); | |
1006 | for (i = 0; i < tp->nr_args; i++) { | |
1007 | /* Set argN as a field */ | |
1008 | sprintf(buf, "arg%d", i); | |
1009 | DEFINE_FIELD(unsigned long, args[i], buf, 0); | |
1010 | /* Set argument string as an alias field */ | |
30a7e073 | 1011 | ret = probe_arg_string(buf, MAX_ARGSTR_LEN, &tp->args[i]); |
413d37d1 MH |
1012 | if (ret < 0) |
1013 | return ret; | |
1014 | DEFINE_FIELD(unsigned long, args[i], buf, 0); | |
1015 | } | |
1016 | return 0; | |
1017 | } | |
1018 | ||
1019 | static int __probe_event_show_format(struct trace_seq *s, | |
1020 | struct trace_probe *tp, const char *fmt, | |
1021 | const char *arg) | |
1022 | { | |
1023 | int i, ret; | |
1024 | char buf[MAX_ARGSTR_LEN + 1]; | |
1025 | ||
1026 | /* Show aliases */ | |
1027 | for (i = 0; i < tp->nr_args; i++) { | |
30a7e073 | 1028 | ret = probe_arg_string(buf, MAX_ARGSTR_LEN, &tp->args[i]); |
413d37d1 MH |
1029 | if (ret < 0) |
1030 | return ret; | |
1031 | if (!trace_seq_printf(s, "\talias: %s;\toriginal: arg%d;\n", | |
1032 | buf, i)) | |
1033 | return 0; | |
1034 | } | |
1035 | /* Show format */ | |
1036 | if (!trace_seq_printf(s, "\nprint fmt: \"%s", fmt)) | |
1037 | return 0; | |
1038 | ||
1039 | for (i = 0; i < tp->nr_args; i++) | |
1040 | if (!trace_seq_puts(s, " 0x%lx")) | |
1041 | return 0; | |
1042 | ||
1043 | if (!trace_seq_printf(s, "\", %s", arg)) | |
1044 | return 0; | |
1045 | ||
1046 | for (i = 0; i < tp->nr_args; i++) | |
1047 | if (!trace_seq_printf(s, ", arg%d", i)) | |
1048 | return 0; | |
1049 | ||
1050 | return trace_seq_puts(s, "\n"); | |
1051 | } | |
1052 | ||
1053 | #undef SHOW_FIELD | |
1054 | #define SHOW_FIELD(type, item, name) \ | |
1055 | do { \ | |
1056 | ret = trace_seq_printf(s, "\tfield: " #type " %s;\t" \ | |
38a47497 | 1057 | "offset:%u;\tsize:%u;\n", name, \ |
413d37d1 MH |
1058 | (unsigned int)offsetof(typeof(field), item),\ |
1059 | (unsigned int)sizeof(type)); \ | |
1060 | if (!ret) \ | |
1061 | return 0; \ | |
1062 | } while (0) | |
1063 | ||
1064 | static int kprobe_event_show_format(struct ftrace_event_call *call, | |
1065 | struct trace_seq *s) | |
1066 | { | |
1067 | struct kprobe_trace_entry field __attribute__((unused)); | |
1068 | int ret, i; | |
1069 | char buf[8]; | |
1070 | struct trace_probe *tp = (struct trace_probe *)call->data; | |
1071 | ||
1072 | SHOW_FIELD(unsigned long, ip, "ip"); | |
1073 | SHOW_FIELD(int, nargs, "nargs"); | |
1074 | ||
1075 | /* Show fields */ | |
1076 | for (i = 0; i < tp->nr_args; i++) { | |
1077 | sprintf(buf, "arg%d", i); | |
1078 | SHOW_FIELD(unsigned long, args[i], buf); | |
1079 | } | |
1080 | trace_seq_puts(s, "\n"); | |
1081 | ||
1082 | return __probe_event_show_format(s, tp, "%lx:", "ip"); | |
1083 | } | |
1084 | ||
1085 | static int kretprobe_event_show_format(struct ftrace_event_call *call, | |
1086 | struct trace_seq *s) | |
1087 | { | |
1088 | struct kretprobe_trace_entry field __attribute__((unused)); | |
1089 | int ret, i; | |
1090 | char buf[8]; | |
1091 | struct trace_probe *tp = (struct trace_probe *)call->data; | |
1092 | ||
1093 | SHOW_FIELD(unsigned long, func, "func"); | |
1094 | SHOW_FIELD(unsigned long, ret_ip, "ret_ip"); | |
1095 | SHOW_FIELD(int, nargs, "nargs"); | |
1096 | ||
1097 | /* Show fields */ | |
1098 | for (i = 0; i < tp->nr_args; i++) { | |
1099 | sprintf(buf, "arg%d", i); | |
1100 | SHOW_FIELD(unsigned long, args[i], buf); | |
1101 | } | |
1102 | trace_seq_puts(s, "\n"); | |
1103 | ||
1104 | return __probe_event_show_format(s, tp, "%lx <- %lx:", | |
1105 | "func, ret_ip"); | |
1106 | } | |
1107 | ||
1108 | static int register_probe_event(struct trace_probe *tp) | |
1109 | { | |
1110 | struct ftrace_event_call *call = &tp->call; | |
1111 | int ret; | |
1112 | ||
1113 | /* Initialize ftrace_event_call */ | |
1114 | call->system = "kprobes"; | |
1115 | if (probe_is_return(tp)) { | |
ff50d991 | 1116 | tp->event.trace = print_kretprobe_event; |
413d37d1 MH |
1117 | call->raw_init = probe_event_raw_init; |
1118 | call->show_format = kretprobe_event_show_format; | |
1119 | call->define_fields = kretprobe_event_define_fields; | |
1120 | } else { | |
ff50d991 | 1121 | tp->event.trace = print_kprobe_event; |
413d37d1 MH |
1122 | call->raw_init = probe_event_raw_init; |
1123 | call->show_format = kprobe_event_show_format; | |
1124 | call->define_fields = kprobe_event_define_fields; | |
1125 | } | |
ff50d991 MH |
1126 | call->event = &tp->event; |
1127 | call->id = register_ftrace_event(&tp->event); | |
1128 | if (!call->id) | |
1129 | return -ENODEV; | |
413d37d1 MH |
1130 | call->enabled = 1; |
1131 | call->regfunc = probe_event_enable; | |
1132 | call->unregfunc = probe_event_disable; | |
1133 | call->data = tp; | |
1134 | ret = trace_add_event_call(call); | |
ff50d991 | 1135 | if (ret) { |
413d37d1 | 1136 | pr_info("Failed to register kprobe event: %s\n", call->name); |
ff50d991 MH |
1137 | unregister_ftrace_event(&tp->event); |
1138 | } | |
413d37d1 MH |
1139 | return ret; |
1140 | } | |
1141 | ||
1142 | static void unregister_probe_event(struct trace_probe *tp) | |
1143 | { | |
ff50d991 | 1144 | /* tp->event is unregistered in trace_remove_event_call() */ |
413d37d1 MH |
1145 | trace_remove_event_call(&tp->call); |
1146 | } | |
1147 | ||
1148 | /* Make a debugfs interface for controling probe points */ | |
1149 | static __init int init_kprobe_trace(void) | |
1150 | { | |
1151 | struct dentry *d_tracer; | |
1152 | struct dentry *entry; | |
413d37d1 MH |
1153 | |
1154 | d_tracer = tracing_init_dentry(); | |
1155 | if (!d_tracer) | |
1156 | return 0; | |
1157 | ||
1158 | entry = debugfs_create_file("kprobe_events", 0644, d_tracer, | |
1159 | NULL, &kprobe_events_ops); | |
1160 | ||
cd7e7bd5 | 1161 | /* Event list interface */ |
413d37d1 MH |
1162 | if (!entry) |
1163 | pr_warning("Could not create debugfs " | |
1164 | "'kprobe_events' entry\n"); | |
cd7e7bd5 MH |
1165 | |
1166 | /* Profile interface */ | |
1167 | entry = debugfs_create_file("kprobe_profile", 0444, d_tracer, | |
1168 | NULL, &kprobe_profile_ops); | |
1169 | ||
1170 | if (!entry) | |
1171 | pr_warning("Could not create debugfs " | |
1172 | "'kprobe_profile' entry\n"); | |
413d37d1 MH |
1173 | return 0; |
1174 | } | |
1175 | fs_initcall(init_kprobe_trace); | |
1176 | ||
1177 | ||
1178 | #ifdef CONFIG_FTRACE_STARTUP_TEST | |
1179 | ||
1180 | static int kprobe_trace_selftest_target(int a1, int a2, int a3, | |
1181 | int a4, int a5, int a6) | |
1182 | { | |
1183 | return a1 + a2 + a3 + a4 + a5 + a6; | |
1184 | } | |
1185 | ||
1186 | static __init int kprobe_trace_self_tests_init(void) | |
1187 | { | |
1188 | int ret; | |
1189 | int (*target)(int, int, int, int, int, int); | |
1190 | ||
1191 | target = kprobe_trace_selftest_target; | |
1192 | ||
1193 | pr_info("Testing kprobe tracing: "); | |
1194 | ||
1195 | ret = command_trace_probe("p:testprobe kprobe_trace_selftest_target " | |
1196 | "a1 a2 a3 a4 a5 a6"); | |
1197 | if (WARN_ON_ONCE(ret)) | |
1198 | pr_warning("error enabling function entry\n"); | |
1199 | ||
1200 | ret = command_trace_probe("r:testprobe2 kprobe_trace_selftest_target " | |
1201 | "ra rv"); | |
1202 | if (WARN_ON_ONCE(ret)) | |
1203 | pr_warning("error enabling function return\n"); | |
1204 | ||
1205 | ret = target(1, 2, 3, 4, 5, 6); | |
1206 | ||
1207 | cleanup_all_probes(); | |
1208 | ||
1209 | pr_cont("OK\n"); | |
1210 | return 0; | |
1211 | } | |
1212 | ||
1213 | late_initcall(kprobe_trace_self_tests_init); | |
1214 | ||
1215 | #endif |