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Commit | Line | Data |
---|---|---|
413d37d1 | 1 | /* |
77b44d1b | 2 | * Kprobes-based tracing events |
413d37d1 MH |
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> | |
413d37d1 | 22 | |
8ab83f56 | 23 | #include "trace_probe.h" |
1ff511e3 | 24 | |
8ab83f56 | 25 | #define KPROBE_EVENT_SYSTEM "kprobes" |
e09c8614 | 26 | |
413d37d1 | 27 | /** |
77b44d1b | 28 | * Kprobe event core functions |
413d37d1 | 29 | */ |
413d37d1 MH |
30 | struct trace_probe { |
31 | struct list_head list; | |
4a846b44 | 32 | struct kretprobe rp; /* Use rp.kp for kprobe use */ |
cd7e7bd5 | 33 | unsigned long nhit; |
50d78056 | 34 | unsigned int flags; /* For TP_FLAG_* */ |
413d37d1 | 35 | const char *symbol; /* symbol name */ |
2239291a | 36 | struct ftrace_event_class class; |
413d37d1 | 37 | struct ftrace_event_call call; |
41a7dd42 | 38 | struct ftrace_event_file **files; |
93ccae7a | 39 | ssize_t size; /* trace entry size */ |
a82378d8 | 40 | unsigned int nr_args; |
eca0d916 | 41 | struct probe_arg args[]; |
413d37d1 MH |
42 | }; |
43 | ||
a82378d8 MH |
44 | #define SIZEOF_TRACE_PROBE(n) \ |
45 | (offsetof(struct trace_probe, args) + \ | |
eca0d916 | 46 | (sizeof(struct probe_arg) * (n))) |
a82378d8 | 47 | |
93ccae7a | 48 | |
db02038f | 49 | static __kprobes bool trace_probe_is_return(struct trace_probe *tp) |
413d37d1 | 50 | { |
4a846b44 | 51 | return tp->rp.handler != NULL; |
413d37d1 MH |
52 | } |
53 | ||
7143f168 | 54 | static __kprobes const char *trace_probe_symbol(struct trace_probe *tp) |
413d37d1 MH |
55 | { |
56 | return tp->symbol ? tp->symbol : "unknown"; | |
57 | } | |
58 | ||
61424318 MH |
59 | static __kprobes unsigned long trace_probe_offset(struct trace_probe *tp) |
60 | { | |
61 | return tp->rp.kp.offset; | |
62 | } | |
63 | ||
64 | static __kprobes bool trace_probe_is_enabled(struct trace_probe *tp) | |
65 | { | |
66 | return !!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE)); | |
67 | } | |
68 | ||
69 | static __kprobes bool trace_probe_is_registered(struct trace_probe *tp) | |
70 | { | |
71 | return !!(tp->flags & TP_FLAG_REGISTERED); | |
72 | } | |
73 | ||
74 | static __kprobes bool trace_probe_has_gone(struct trace_probe *tp) | |
75 | { | |
76 | return !!(kprobe_gone(&tp->rp.kp)); | |
77 | } | |
78 | ||
79 | static __kprobes bool trace_probe_within_module(struct trace_probe *tp, | |
80 | struct module *mod) | |
81 | { | |
82 | int len = strlen(mod->name); | |
83 | const char *name = trace_probe_symbol(tp); | |
84 | return strncmp(mod->name, name, len) == 0 && name[len] == ':'; | |
85 | } | |
86 | ||
87 | static __kprobes bool trace_probe_is_on_module(struct trace_probe *tp) | |
88 | { | |
89 | return !!strchr(trace_probe_symbol(tp), ':'); | |
90 | } | |
91 | ||
413d37d1 MH |
92 | static int register_probe_event(struct trace_probe *tp); |
93 | static void unregister_probe_event(struct trace_probe *tp); | |
94 | ||
95 | static DEFINE_MUTEX(probe_lock); | |
96 | static LIST_HEAD(probe_list); | |
97 | ||
50d78056 MH |
98 | static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs); |
99 | static int kretprobe_dispatcher(struct kretprobe_instance *ri, | |
100 | struct pt_regs *regs); | |
101 | ||
4a846b44 MH |
102 | /* |
103 | * Allocate new trace_probe and initialize it (including kprobes). | |
104 | */ | |
f52487e9 MH |
105 | static struct trace_probe *alloc_trace_probe(const char *group, |
106 | const char *event, | |
4a846b44 MH |
107 | void *addr, |
108 | const char *symbol, | |
109 | unsigned long offs, | |
3a6b7666 | 110 | int nargs, bool is_return) |
413d37d1 MH |
111 | { |
112 | struct trace_probe *tp; | |
6f3cf440 | 113 | int ret = -ENOMEM; |
413d37d1 | 114 | |
a82378d8 | 115 | tp = kzalloc(SIZEOF_TRACE_PROBE(nargs), GFP_KERNEL); |
413d37d1 | 116 | if (!tp) |
6f3cf440 | 117 | return ERR_PTR(ret); |
413d37d1 MH |
118 | |
119 | if (symbol) { | |
120 | tp->symbol = kstrdup(symbol, GFP_KERNEL); | |
121 | if (!tp->symbol) | |
122 | goto error; | |
4a846b44 MH |
123 | tp->rp.kp.symbol_name = tp->symbol; |
124 | tp->rp.kp.offset = offs; | |
125 | } else | |
126 | tp->rp.kp.addr = addr; | |
127 | ||
128 | if (is_return) | |
50d78056 | 129 | tp->rp.handler = kretprobe_dispatcher; |
4a846b44 | 130 | else |
50d78056 | 131 | tp->rp.kp.pre_handler = kprobe_dispatcher; |
4a846b44 | 132 | |
da34634f | 133 | if (!event || !is_good_name(event)) { |
6f3cf440 | 134 | ret = -EINVAL; |
4263565d | 135 | goto error; |
6f3cf440 MH |
136 | } |
137 | ||
2239291a | 138 | tp->call.class = &tp->class; |
4263565d MH |
139 | tp->call.name = kstrdup(event, GFP_KERNEL); |
140 | if (!tp->call.name) | |
141 | goto error; | |
413d37d1 | 142 | |
da34634f | 143 | if (!group || !is_good_name(group)) { |
6f3cf440 | 144 | ret = -EINVAL; |
f52487e9 | 145 | goto error; |
6f3cf440 MH |
146 | } |
147 | ||
2239291a SR |
148 | tp->class.system = kstrdup(group, GFP_KERNEL); |
149 | if (!tp->class.system) | |
f52487e9 MH |
150 | goto error; |
151 | ||
413d37d1 MH |
152 | INIT_LIST_HEAD(&tp->list); |
153 | return tp; | |
154 | error: | |
f52487e9 | 155 | kfree(tp->call.name); |
413d37d1 MH |
156 | kfree(tp->symbol); |
157 | kfree(tp); | |
6f3cf440 | 158 | return ERR_PTR(ret); |
413d37d1 MH |
159 | } |
160 | ||
161 | static void free_trace_probe(struct trace_probe *tp) | |
162 | { | |
163 | int i; | |
164 | ||
165 | for (i = 0; i < tp->nr_args; i++) | |
8ab83f56 | 166 | traceprobe_free_probe_arg(&tp->args[i]); |
413d37d1 | 167 | |
8f082018 | 168 | kfree(tp->call.class->system); |
413d37d1 MH |
169 | kfree(tp->call.name); |
170 | kfree(tp->symbol); | |
171 | kfree(tp); | |
172 | } | |
173 | ||
7143f168 | 174 | static struct trace_probe *find_trace_probe(const char *event, |
dd004c47 | 175 | const char *group) |
413d37d1 MH |
176 | { |
177 | struct trace_probe *tp; | |
178 | ||
179 | list_for_each_entry(tp, &probe_list, list) | |
dd004c47 | 180 | if (strcmp(tp->call.name, event) == 0 && |
8f082018 | 181 | strcmp(tp->call.class->system, group) == 0) |
413d37d1 MH |
182 | return tp; |
183 | return NULL; | |
184 | } | |
185 | ||
41a7dd42 MH |
186 | static int trace_probe_nr_files(struct trace_probe *tp) |
187 | { | |
188 | struct ftrace_event_file **file = tp->files; | |
189 | int ret = 0; | |
190 | ||
191 | if (file) | |
192 | while (*(file++)) | |
193 | ret++; | |
194 | ||
195 | return ret; | |
196 | } | |
197 | ||
198 | static DEFINE_MUTEX(probe_enable_lock); | |
199 | ||
200 | /* | |
201 | * Enable trace_probe | |
202 | * if the file is NULL, enable "perf" handler, or enable "trace" handler. | |
203 | */ | |
204 | static int | |
205 | enable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file) | |
1538f888 MH |
206 | { |
207 | int ret = 0; | |
208 | ||
41a7dd42 MH |
209 | mutex_lock(&probe_enable_lock); |
210 | ||
211 | if (file) { | |
212 | struct ftrace_event_file **new, **old = tp->files; | |
213 | int n = trace_probe_nr_files(tp); | |
214 | ||
215 | /* 1 is for new one and 1 is for stopper */ | |
216 | new = kzalloc((n + 2) * sizeof(struct ftrace_event_file *), | |
217 | GFP_KERNEL); | |
218 | if (!new) { | |
219 | ret = -ENOMEM; | |
220 | goto out_unlock; | |
221 | } | |
222 | memcpy(new, old, n * sizeof(struct ftrace_event_file *)); | |
223 | new[n] = file; | |
224 | /* The last one keeps a NULL */ | |
225 | ||
226 | rcu_assign_pointer(tp->files, new); | |
227 | tp->flags |= TP_FLAG_TRACE; | |
228 | ||
229 | if (old) { | |
230 | /* Make sure the probe is done with old files */ | |
231 | synchronize_sched(); | |
232 | kfree(old); | |
233 | } | |
234 | } else | |
235 | tp->flags |= TP_FLAG_PROFILE; | |
236 | ||
61424318 MH |
237 | if (trace_probe_is_enabled(tp) && trace_probe_is_registered(tp) && |
238 | !trace_probe_has_gone(tp)) { | |
1538f888 MH |
239 | if (trace_probe_is_return(tp)) |
240 | ret = enable_kretprobe(&tp->rp); | |
241 | else | |
242 | ret = enable_kprobe(&tp->rp.kp); | |
243 | } | |
244 | ||
41a7dd42 MH |
245 | out_unlock: |
246 | mutex_unlock(&probe_enable_lock); | |
247 | ||
1538f888 MH |
248 | return ret; |
249 | } | |
250 | ||
41a7dd42 MH |
251 | static int |
252 | trace_probe_file_index(struct trace_probe *tp, struct ftrace_event_file *file) | |
253 | { | |
254 | int i; | |
255 | ||
256 | if (tp->files) { | |
257 | for (i = 0; tp->files[i]; i++) | |
258 | if (tp->files[i] == file) | |
259 | return i; | |
260 | } | |
261 | ||
262 | return -1; | |
263 | } | |
264 | ||
265 | /* | |
266 | * Disable trace_probe | |
267 | * if the file is NULL, disable "perf" handler, or disable "trace" handler. | |
268 | */ | |
269 | static int | |
270 | disable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file) | |
1538f888 | 271 | { |
41a7dd42 MH |
272 | int ret = 0; |
273 | ||
274 | mutex_lock(&probe_enable_lock); | |
275 | ||
276 | if (file) { | |
277 | struct ftrace_event_file **new, **old = tp->files; | |
278 | int n = trace_probe_nr_files(tp); | |
279 | int i, j; | |
280 | ||
281 | if (n == 0 || trace_probe_file_index(tp, file) < 0) { | |
282 | ret = -EINVAL; | |
283 | goto out_unlock; | |
284 | } | |
285 | ||
286 | if (n == 1) { /* Remove the last file */ | |
287 | tp->flags &= ~TP_FLAG_TRACE; | |
288 | new = NULL; | |
289 | } else { | |
290 | new = kzalloc(n * sizeof(struct ftrace_event_file *), | |
291 | GFP_KERNEL); | |
292 | if (!new) { | |
293 | ret = -ENOMEM; | |
294 | goto out_unlock; | |
295 | } | |
296 | ||
297 | /* This copy & check loop copies the NULL stopper too */ | |
298 | for (i = 0, j = 0; j < n && i < n + 1; i++) | |
299 | if (old[i] != file) | |
300 | new[j++] = old[i]; | |
301 | } | |
302 | ||
303 | rcu_assign_pointer(tp->files, new); | |
304 | ||
305 | /* Make sure the probe is done with old files */ | |
306 | synchronize_sched(); | |
307 | kfree(old); | |
308 | } else | |
309 | tp->flags &= ~TP_FLAG_PROFILE; | |
310 | ||
61424318 | 311 | if (!trace_probe_is_enabled(tp) && trace_probe_is_registered(tp)) { |
1538f888 MH |
312 | if (trace_probe_is_return(tp)) |
313 | disable_kretprobe(&tp->rp); | |
314 | else | |
315 | disable_kprobe(&tp->rp.kp); | |
316 | } | |
41a7dd42 MH |
317 | |
318 | out_unlock: | |
319 | mutex_unlock(&probe_enable_lock); | |
320 | ||
321 | return ret; | |
1538f888 MH |
322 | } |
323 | ||
61424318 MH |
324 | /* Internal register function - just handle k*probes and flags */ |
325 | static int __register_trace_probe(struct trace_probe *tp) | |
413d37d1 | 326 | { |
7f6878a3 | 327 | int i, ret; |
61424318 MH |
328 | |
329 | if (trace_probe_is_registered(tp)) | |
330 | return -EINVAL; | |
331 | ||
7f6878a3 | 332 | for (i = 0; i < tp->nr_args; i++) |
8ab83f56 | 333 | traceprobe_update_arg(&tp->args[i]); |
7f6878a3 | 334 | |
61424318 MH |
335 | /* Set/clear disabled flag according to tp->flag */ |
336 | if (trace_probe_is_enabled(tp)) | |
337 | tp->rp.kp.flags &= ~KPROBE_FLAG_DISABLED; | |
338 | else | |
339 | tp->rp.kp.flags |= KPROBE_FLAG_DISABLED; | |
340 | ||
7143f168 | 341 | if (trace_probe_is_return(tp)) |
61424318 | 342 | ret = register_kretprobe(&tp->rp); |
413d37d1 | 343 | else |
61424318 MH |
344 | ret = register_kprobe(&tp->rp.kp); |
345 | ||
346 | if (ret == 0) | |
347 | tp->flags |= TP_FLAG_REGISTERED; | |
348 | else { | |
349 | pr_warning("Could not insert probe at %s+%lu: %d\n", | |
350 | trace_probe_symbol(tp), trace_probe_offset(tp), ret); | |
351 | if (ret == -ENOENT && trace_probe_is_on_module(tp)) { | |
352 | pr_warning("This probe might be able to register after" | |
353 | "target module is loaded. Continue.\n"); | |
354 | ret = 0; | |
355 | } else if (ret == -EILSEQ) { | |
356 | pr_warning("Probing address(0x%p) is not an " | |
357 | "instruction boundary.\n", | |
358 | tp->rp.kp.addr); | |
359 | ret = -EINVAL; | |
360 | } | |
361 | } | |
362 | ||
363 | return ret; | |
364 | } | |
365 | ||
366 | /* Internal unregister function - just handle k*probes and flags */ | |
367 | static void __unregister_trace_probe(struct trace_probe *tp) | |
368 | { | |
369 | if (trace_probe_is_registered(tp)) { | |
370 | if (trace_probe_is_return(tp)) | |
371 | unregister_kretprobe(&tp->rp); | |
372 | else | |
373 | unregister_kprobe(&tp->rp.kp); | |
374 | tp->flags &= ~TP_FLAG_REGISTERED; | |
375 | /* Cleanup kprobe for reuse */ | |
376 | if (tp->rp.kp.symbol_name) | |
377 | tp->rp.kp.addr = NULL; | |
378 | } | |
379 | } | |
380 | ||
381 | /* Unregister a trace_probe and probe_event: call with locking probe_lock */ | |
02ca1521 | 382 | static int unregister_trace_probe(struct trace_probe *tp) |
61424318 | 383 | { |
02ca1521 MH |
384 | /* Enabled event can not be unregistered */ |
385 | if (trace_probe_is_enabled(tp)) | |
386 | return -EBUSY; | |
387 | ||
61424318 | 388 | __unregister_trace_probe(tp); |
413d37d1 | 389 | list_del(&tp->list); |
2d5e067e | 390 | unregister_probe_event(tp); |
02ca1521 MH |
391 | |
392 | return 0; | |
413d37d1 MH |
393 | } |
394 | ||
395 | /* Register a trace_probe and probe_event */ | |
396 | static int register_trace_probe(struct trace_probe *tp) | |
397 | { | |
398 | struct trace_probe *old_tp; | |
399 | int ret; | |
400 | ||
401 | mutex_lock(&probe_lock); | |
402 | ||
61424318 | 403 | /* Delete old (same name) event if exist */ |
7143f168 | 404 | old_tp = find_trace_probe(tp->call.name, tp->call.class->system); |
2d5e067e | 405 | if (old_tp) { |
02ca1521 MH |
406 | ret = unregister_trace_probe(old_tp); |
407 | if (ret < 0) | |
408 | goto end; | |
2d5e067e MH |
409 | free_trace_probe(old_tp); |
410 | } | |
61424318 MH |
411 | |
412 | /* Register new event */ | |
2d5e067e MH |
413 | ret = register_probe_event(tp); |
414 | if (ret) { | |
426d3107 | 415 | pr_warning("Failed to register probe event(%d)\n", ret); |
2d5e067e MH |
416 | goto end; |
417 | } | |
418 | ||
61424318 MH |
419 | /* Register k*probe */ |
420 | ret = __register_trace_probe(tp); | |
421 | if (ret < 0) | |
2d5e067e | 422 | unregister_probe_event(tp); |
61424318 | 423 | else |
2d5e067e | 424 | list_add_tail(&tp->list, &probe_list); |
61424318 | 425 | |
413d37d1 MH |
426 | end: |
427 | mutex_unlock(&probe_lock); | |
428 | return ret; | |
429 | } | |
430 | ||
61424318 MH |
431 | /* Module notifier call back, checking event on the module */ |
432 | static int trace_probe_module_callback(struct notifier_block *nb, | |
433 | unsigned long val, void *data) | |
434 | { | |
435 | struct module *mod = data; | |
436 | struct trace_probe *tp; | |
437 | int ret; | |
438 | ||
439 | if (val != MODULE_STATE_COMING) | |
440 | return NOTIFY_DONE; | |
441 | ||
442 | /* Update probes on coming module */ | |
443 | mutex_lock(&probe_lock); | |
444 | list_for_each_entry(tp, &probe_list, list) { | |
445 | if (trace_probe_within_module(tp, mod)) { | |
02ca1521 | 446 | /* Don't need to check busy - this should have gone. */ |
61424318 MH |
447 | __unregister_trace_probe(tp); |
448 | ret = __register_trace_probe(tp); | |
449 | if (ret) | |
450 | pr_warning("Failed to re-register probe %s on" | |
451 | "%s: %d\n", | |
452 | tp->call.name, mod->name, ret); | |
453 | } | |
454 | } | |
455 | mutex_unlock(&probe_lock); | |
456 | ||
457 | return NOTIFY_DONE; | |
458 | } | |
459 | ||
460 | static struct notifier_block trace_probe_module_nb = { | |
461 | .notifier_call = trace_probe_module_callback, | |
462 | .priority = 1 /* Invoked after kprobe module callback */ | |
463 | }; | |
464 | ||
413d37d1 MH |
465 | static int create_trace_probe(int argc, char **argv) |
466 | { | |
467 | /* | |
468 | * Argument syntax: | |
61424318 MH |
469 | * - Add kprobe: p[:[GRP/]EVENT] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS] |
470 | * - Add kretprobe: r[:[GRP/]EVENT] [MOD:]KSYM[+0] [FETCHARGS] | |
413d37d1 | 471 | * Fetch args: |
2e06ff63 MH |
472 | * $retval : fetch return value |
473 | * $stack : fetch stack address | |
474 | * $stackN : fetch Nth of stack (N:0-) | |
413d37d1 MH |
475 | * @ADDR : fetch memory at ADDR (ADDR should be in kernel) |
476 | * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol) | |
477 | * %REG : fetch register REG | |
93ccae7a | 478 | * Dereferencing memory fetch: |
413d37d1 | 479 | * +|-offs(ARG) : fetch memory at ARG +|- offs address. |
eca0d916 MH |
480 | * Alias name of args: |
481 | * NAME=FETCHARG : set NAME as alias of FETCHARG. | |
93ccae7a MH |
482 | * Type of args: |
483 | * FETCHARG:TYPE : use TYPE instead of unsigned long. | |
413d37d1 MH |
484 | */ |
485 | struct trace_probe *tp; | |
413d37d1 | 486 | int i, ret = 0; |
3a6b7666 | 487 | bool is_return = false, is_delete = false; |
93ccae7a | 488 | char *symbol = NULL, *event = NULL, *group = NULL; |
da34634f | 489 | char *arg; |
2fba0c88 | 490 | unsigned long offset = 0; |
413d37d1 | 491 | void *addr = NULL; |
4a846b44 | 492 | char buf[MAX_EVENT_NAME_LEN]; |
413d37d1 | 493 | |
a7c312be | 494 | /* argc must be >= 1 */ |
413d37d1 | 495 | if (argv[0][0] == 'p') |
3a6b7666 | 496 | is_return = false; |
413d37d1 | 497 | else if (argv[0][0] == 'r') |
3a6b7666 | 498 | is_return = true; |
a7c312be | 499 | else if (argv[0][0] == '-') |
3a6b7666 | 500 | is_delete = true; |
e63cc239 | 501 | else { |
a7c312be MH |
502 | pr_info("Probe definition must be started with 'p', 'r' or" |
503 | " '-'.\n"); | |
413d37d1 | 504 | return -EINVAL; |
e63cc239 | 505 | } |
413d37d1 MH |
506 | |
507 | if (argv[0][1] == ':') { | |
508 | event = &argv[0][2]; | |
f52487e9 MH |
509 | if (strchr(event, '/')) { |
510 | group = event; | |
511 | event = strchr(group, '/') + 1; | |
512 | event[-1] = '\0'; | |
513 | if (strlen(group) == 0) { | |
a5efd925 | 514 | pr_info("Group name is not specified\n"); |
f52487e9 MH |
515 | return -EINVAL; |
516 | } | |
517 | } | |
413d37d1 | 518 | if (strlen(event) == 0) { |
a5efd925 | 519 | pr_info("Event name is not specified\n"); |
413d37d1 MH |
520 | return -EINVAL; |
521 | } | |
522 | } | |
a7c312be MH |
523 | if (!group) |
524 | group = KPROBE_EVENT_SYSTEM; | |
413d37d1 | 525 | |
a7c312be MH |
526 | if (is_delete) { |
527 | if (!event) { | |
528 | pr_info("Delete command needs an event name.\n"); | |
529 | return -EINVAL; | |
530 | } | |
9da79ab8 | 531 | mutex_lock(&probe_lock); |
7143f168 | 532 | tp = find_trace_probe(event, group); |
a7c312be | 533 | if (!tp) { |
9da79ab8 | 534 | mutex_unlock(&probe_lock); |
a7c312be MH |
535 | pr_info("Event %s/%s doesn't exist.\n", group, event); |
536 | return -ENOENT; | |
537 | } | |
538 | /* delete an event */ | |
02ca1521 MH |
539 | ret = unregister_trace_probe(tp); |
540 | if (ret == 0) | |
541 | free_trace_probe(tp); | |
9da79ab8 | 542 | mutex_unlock(&probe_lock); |
02ca1521 | 543 | return ret; |
a7c312be MH |
544 | } |
545 | ||
546 | if (argc < 2) { | |
547 | pr_info("Probe point is not specified.\n"); | |
548 | return -EINVAL; | |
549 | } | |
413d37d1 | 550 | if (isdigit(argv[1][0])) { |
e63cc239 MH |
551 | if (is_return) { |
552 | pr_info("Return probe point must be a symbol.\n"); | |
413d37d1 | 553 | return -EINVAL; |
e63cc239 | 554 | } |
413d37d1 | 555 | /* an address specified */ |
bcd83ea6 | 556 | ret = kstrtoul(&argv[1][0], 0, (unsigned long *)&addr); |
e63cc239 MH |
557 | if (ret) { |
558 | pr_info("Failed to parse address.\n"); | |
413d37d1 | 559 | return ret; |
e63cc239 | 560 | } |
413d37d1 MH |
561 | } else { |
562 | /* a symbol specified */ | |
563 | symbol = argv[1]; | |
564 | /* TODO: support .init module functions */ | |
8ab83f56 | 565 | ret = traceprobe_split_symbol_offset(symbol, &offset); |
e63cc239 MH |
566 | if (ret) { |
567 | pr_info("Failed to parse symbol.\n"); | |
413d37d1 | 568 | return ret; |
e63cc239 MH |
569 | } |
570 | if (offset && is_return) { | |
571 | pr_info("Return probe must be used without offset.\n"); | |
413d37d1 | 572 | return -EINVAL; |
e63cc239 | 573 | } |
413d37d1 | 574 | } |
a82378d8 | 575 | argc -= 2; argv += 2; |
413d37d1 MH |
576 | |
577 | /* setup a probe */ | |
4263565d MH |
578 | if (!event) { |
579 | /* Make a new event name */ | |
4263565d | 580 | if (symbol) |
6f3cf440 | 581 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld", |
4263565d MH |
582 | is_return ? 'r' : 'p', symbol, offset); |
583 | else | |
6f3cf440 | 584 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p", |
4263565d | 585 | is_return ? 'r' : 'p', addr); |
4a846b44 MH |
586 | event = buf; |
587 | } | |
f52487e9 MH |
588 | tp = alloc_trace_probe(group, event, addr, symbol, offset, argc, |
589 | is_return); | |
e63cc239 MH |
590 | if (IS_ERR(tp)) { |
591 | pr_info("Failed to allocate trace_probe.(%d)\n", | |
592 | (int)PTR_ERR(tp)); | |
413d37d1 | 593 | return PTR_ERR(tp); |
e63cc239 | 594 | } |
413d37d1 | 595 | |
413d37d1 | 596 | /* parse arguments */ |
a82378d8 MH |
597 | ret = 0; |
598 | for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { | |
61a52736 MH |
599 | /* Increment count for freeing args in error case */ |
600 | tp->nr_args++; | |
601 | ||
eca0d916 MH |
602 | /* Parse argument name */ |
603 | arg = strchr(argv[i], '='); | |
aba91595 | 604 | if (arg) { |
eca0d916 | 605 | *arg++ = '\0'; |
aba91595 MH |
606 | tp->args[i].name = kstrdup(argv[i], GFP_KERNEL); |
607 | } else { | |
eca0d916 | 608 | arg = argv[i]; |
aba91595 MH |
609 | /* If argument name is omitted, set "argN" */ |
610 | snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1); | |
611 | tp->args[i].name = kstrdup(buf, GFP_KERNEL); | |
612 | } | |
a703d946 | 613 | |
ba8665d7 | 614 | if (!tp->args[i].name) { |
aba91595 | 615 | pr_info("Failed to allocate argument[%d] name.\n", i); |
ba8665d7 | 616 | ret = -ENOMEM; |
413d37d1 MH |
617 | goto error; |
618 | } | |
da34634f MH |
619 | |
620 | if (!is_good_name(tp->args[i].name)) { | |
621 | pr_info("Invalid argument[%d] name: %s\n", | |
622 | i, tp->args[i].name); | |
623 | ret = -EINVAL; | |
624 | goto error; | |
625 | } | |
93ccae7a | 626 | |
8ab83f56 SD |
627 | if (traceprobe_conflict_field_name(tp->args[i].name, |
628 | tp->args, i)) { | |
aba91595 | 629 | pr_info("Argument[%d] name '%s' conflicts with " |
93ccae7a MH |
630 | "another field.\n", i, argv[i]); |
631 | ret = -EINVAL; | |
632 | goto error; | |
633 | } | |
ba8665d7 MH |
634 | |
635 | /* Parse fetch argument */ | |
8ab83f56 | 636 | ret = traceprobe_parse_probe_arg(arg, &tp->size, &tp->args[i], |
f3f096cf | 637 | is_return, true); |
e63cc239 | 638 | if (ret) { |
aba91595 | 639 | pr_info("Parse error at argument[%d]. (%d)\n", i, ret); |
413d37d1 | 640 | goto error; |
e63cc239 | 641 | } |
413d37d1 | 642 | } |
413d37d1 MH |
643 | |
644 | ret = register_trace_probe(tp); | |
645 | if (ret) | |
646 | goto error; | |
647 | return 0; | |
648 | ||
649 | error: | |
650 | free_trace_probe(tp); | |
651 | return ret; | |
652 | } | |
653 | ||
02ca1521 | 654 | static int release_all_trace_probes(void) |
413d37d1 MH |
655 | { |
656 | struct trace_probe *tp; | |
02ca1521 | 657 | int ret = 0; |
413d37d1 MH |
658 | |
659 | mutex_lock(&probe_lock); | |
02ca1521 MH |
660 | /* Ensure no probe is in use. */ |
661 | list_for_each_entry(tp, &probe_list, list) | |
662 | if (trace_probe_is_enabled(tp)) { | |
663 | ret = -EBUSY; | |
664 | goto end; | |
665 | } | |
413d37d1 MH |
666 | /* TODO: Use batch unregistration */ |
667 | while (!list_empty(&probe_list)) { | |
668 | tp = list_entry(probe_list.next, struct trace_probe, list); | |
669 | unregister_trace_probe(tp); | |
670 | free_trace_probe(tp); | |
671 | } | |
02ca1521 MH |
672 | |
673 | end: | |
413d37d1 | 674 | mutex_unlock(&probe_lock); |
02ca1521 MH |
675 | |
676 | return ret; | |
413d37d1 MH |
677 | } |
678 | ||
413d37d1 MH |
679 | /* Probes listing interfaces */ |
680 | static void *probes_seq_start(struct seq_file *m, loff_t *pos) | |
681 | { | |
682 | mutex_lock(&probe_lock); | |
683 | return seq_list_start(&probe_list, *pos); | |
684 | } | |
685 | ||
686 | static void *probes_seq_next(struct seq_file *m, void *v, loff_t *pos) | |
687 | { | |
688 | return seq_list_next(v, &probe_list, pos); | |
689 | } | |
690 | ||
691 | static void probes_seq_stop(struct seq_file *m, void *v) | |
692 | { | |
693 | mutex_unlock(&probe_lock); | |
694 | } | |
695 | ||
696 | static int probes_seq_show(struct seq_file *m, void *v) | |
697 | { | |
698 | struct trace_probe *tp = v; | |
93ccae7a | 699 | int i; |
413d37d1 | 700 | |
7143f168 | 701 | seq_printf(m, "%c", trace_probe_is_return(tp) ? 'r' : 'p'); |
8f082018 | 702 | seq_printf(m, ":%s/%s", tp->call.class->system, tp->call.name); |
413d37d1 | 703 | |
52a11f35 LJ |
704 | if (!tp->symbol) |
705 | seq_printf(m, " 0x%p", tp->rp.kp.addr); | |
706 | else if (tp->rp.kp.offset) | |
7143f168 MH |
707 | seq_printf(m, " %s+%u", trace_probe_symbol(tp), |
708 | tp->rp.kp.offset); | |
413d37d1 | 709 | else |
7143f168 | 710 | seq_printf(m, " %s", trace_probe_symbol(tp)); |
413d37d1 | 711 | |
93ccae7a MH |
712 | for (i = 0; i < tp->nr_args; i++) |
713 | seq_printf(m, " %s=%s", tp->args[i].name, tp->args[i].comm); | |
413d37d1 | 714 | seq_printf(m, "\n"); |
93ccae7a | 715 | |
413d37d1 MH |
716 | return 0; |
717 | } | |
718 | ||
719 | static const struct seq_operations probes_seq_op = { | |
720 | .start = probes_seq_start, | |
721 | .next = probes_seq_next, | |
722 | .stop = probes_seq_stop, | |
723 | .show = probes_seq_show | |
724 | }; | |
725 | ||
726 | static int probes_open(struct inode *inode, struct file *file) | |
727 | { | |
02ca1521 MH |
728 | int ret; |
729 | ||
730 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { | |
731 | ret = release_all_trace_probes(); | |
732 | if (ret < 0) | |
733 | return ret; | |
734 | } | |
413d37d1 MH |
735 | |
736 | return seq_open(file, &probes_seq_op); | |
737 | } | |
738 | ||
413d37d1 MH |
739 | static ssize_t probes_write(struct file *file, const char __user *buffer, |
740 | size_t count, loff_t *ppos) | |
741 | { | |
8ab83f56 SD |
742 | return traceprobe_probes_write(file, buffer, count, ppos, |
743 | create_trace_probe); | |
413d37d1 MH |
744 | } |
745 | ||
746 | static const struct file_operations kprobe_events_ops = { | |
747 | .owner = THIS_MODULE, | |
748 | .open = probes_open, | |
749 | .read = seq_read, | |
750 | .llseek = seq_lseek, | |
751 | .release = seq_release, | |
752 | .write = probes_write, | |
753 | }; | |
754 | ||
cd7e7bd5 MH |
755 | /* Probes profiling interfaces */ |
756 | static int probes_profile_seq_show(struct seq_file *m, void *v) | |
757 | { | |
758 | struct trace_probe *tp = v; | |
759 | ||
760 | seq_printf(m, " %-44s %15lu %15lu\n", tp->call.name, tp->nhit, | |
4a846b44 | 761 | tp->rp.kp.nmissed); |
cd7e7bd5 MH |
762 | |
763 | return 0; | |
764 | } | |
765 | ||
766 | static const struct seq_operations profile_seq_op = { | |
767 | .start = probes_seq_start, | |
768 | .next = probes_seq_next, | |
769 | .stop = probes_seq_stop, | |
770 | .show = probes_profile_seq_show | |
771 | }; | |
772 | ||
773 | static int profile_open(struct inode *inode, struct file *file) | |
774 | { | |
775 | return seq_open(file, &profile_seq_op); | |
776 | } | |
777 | ||
778 | static const struct file_operations kprobe_profile_ops = { | |
779 | .owner = THIS_MODULE, | |
780 | .open = profile_open, | |
781 | .read = seq_read, | |
782 | .llseek = seq_lseek, | |
783 | .release = seq_release, | |
784 | }; | |
785 | ||
e09c8614 MH |
786 | /* Sum up total data length for dynamic arraies (strings) */ |
787 | static __kprobes int __get_data_size(struct trace_probe *tp, | |
788 | struct pt_regs *regs) | |
789 | { | |
790 | int i, ret = 0; | |
791 | u32 len; | |
792 | ||
793 | for (i = 0; i < tp->nr_args; i++) | |
794 | if (unlikely(tp->args[i].fetch_size.fn)) { | |
795 | call_fetch(&tp->args[i].fetch_size, regs, &len); | |
796 | ret += len; | |
797 | } | |
798 | ||
799 | return ret; | |
800 | } | |
801 | ||
802 | /* Store the value of each argument */ | |
803 | static __kprobes void store_trace_args(int ent_size, struct trace_probe *tp, | |
804 | struct pt_regs *regs, | |
805 | u8 *data, int maxlen) | |
806 | { | |
807 | int i; | |
808 | u32 end = tp->size; | |
809 | u32 *dl; /* Data (relative) location */ | |
810 | ||
811 | for (i = 0; i < tp->nr_args; i++) { | |
812 | if (unlikely(tp->args[i].fetch_size.fn)) { | |
813 | /* | |
814 | * First, we set the relative location and | |
815 | * maximum data length to *dl | |
816 | */ | |
817 | dl = (u32 *)(data + tp->args[i].offset); | |
818 | *dl = make_data_rloc(maxlen, end - tp->args[i].offset); | |
819 | /* Then try to fetch string or dynamic array data */ | |
820 | call_fetch(&tp->args[i].fetch, regs, dl); | |
821 | /* Reduce maximum length */ | |
822 | end += get_rloc_len(*dl); | |
823 | maxlen -= get_rloc_len(*dl); | |
824 | /* Trick here, convert data_rloc to data_loc */ | |
825 | *dl = convert_rloc_to_loc(*dl, | |
826 | ent_size + tp->args[i].offset); | |
827 | } else | |
828 | /* Just fetching data normally */ | |
829 | call_fetch(&tp->args[i].fetch, regs, | |
830 | data + tp->args[i].offset); | |
831 | } | |
832 | } | |
833 | ||
413d37d1 | 834 | /* Kprobe handler */ |
2b106aab | 835 | static __kprobes void |
41a7dd42 MH |
836 | __kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs, |
837 | struct ftrace_event_file *ftrace_file) | |
413d37d1 | 838 | { |
93ccae7a | 839 | struct kprobe_trace_entry_head *entry; |
413d37d1 | 840 | struct ring_buffer_event *event; |
8f8ffe24 | 841 | struct ring_buffer *buffer; |
e09c8614 | 842 | int size, dsize, pc; |
413d37d1 | 843 | unsigned long irq_flags; |
4263565d | 844 | struct ftrace_event_call *call = &tp->call; |
413d37d1 | 845 | |
41a7dd42 MH |
846 | WARN_ON(call != ftrace_file->event_call); |
847 | ||
413d37d1 MH |
848 | local_save_flags(irq_flags); |
849 | pc = preempt_count(); | |
850 | ||
e09c8614 MH |
851 | dsize = __get_data_size(tp, regs); |
852 | size = sizeof(*entry) + tp->size + dsize; | |
413d37d1 | 853 | |
41a7dd42 MH |
854 | event = trace_event_buffer_lock_reserve(&buffer, ftrace_file, |
855 | call->event.type, | |
856 | size, irq_flags, pc); | |
413d37d1 | 857 | if (!event) |
1e12a4a7 | 858 | return; |
413d37d1 MH |
859 | |
860 | entry = ring_buffer_event_data(event); | |
2b106aab | 861 | entry->ip = (unsigned long)tp->rp.kp.addr; |
e09c8614 | 862 | store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); |
413d37d1 | 863 | |
8f8ffe24 | 864 | if (!filter_current_check_discard(buffer, call, entry, event)) |
0d5c6e1c SR |
865 | trace_buffer_unlock_commit_regs(buffer, event, |
866 | irq_flags, pc, regs); | |
413d37d1 MH |
867 | } |
868 | ||
41a7dd42 MH |
869 | static __kprobes void |
870 | kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs) | |
871 | { | |
872 | struct ftrace_event_file **file = tp->files; | |
873 | ||
874 | /* Note: preempt is already disabled around the kprobe handler */ | |
875 | while (*file) { | |
876 | __kprobe_trace_func(tp, regs, *file); | |
877 | file++; | |
878 | } | |
879 | } | |
880 | ||
413d37d1 | 881 | /* Kretprobe handler */ |
2b106aab | 882 | static __kprobes void |
41a7dd42 MH |
883 | __kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri, |
884 | struct pt_regs *regs, | |
885 | struct ftrace_event_file *ftrace_file) | |
413d37d1 | 886 | { |
93ccae7a | 887 | struct kretprobe_trace_entry_head *entry; |
413d37d1 | 888 | struct ring_buffer_event *event; |
8f8ffe24 | 889 | struct ring_buffer *buffer; |
e09c8614 | 890 | int size, pc, dsize; |
413d37d1 | 891 | unsigned long irq_flags; |
4263565d | 892 | struct ftrace_event_call *call = &tp->call; |
413d37d1 | 893 | |
41a7dd42 MH |
894 | WARN_ON(call != ftrace_file->event_call); |
895 | ||
413d37d1 MH |
896 | local_save_flags(irq_flags); |
897 | pc = preempt_count(); | |
898 | ||
e09c8614 MH |
899 | dsize = __get_data_size(tp, regs); |
900 | size = sizeof(*entry) + tp->size + dsize; | |
413d37d1 | 901 | |
41a7dd42 MH |
902 | event = trace_event_buffer_lock_reserve(&buffer, ftrace_file, |
903 | call->event.type, | |
904 | size, irq_flags, pc); | |
413d37d1 | 905 | if (!event) |
1e12a4a7 | 906 | return; |
413d37d1 MH |
907 | |
908 | entry = ring_buffer_event_data(event); | |
4a846b44 | 909 | entry->func = (unsigned long)tp->rp.kp.addr; |
413d37d1 | 910 | entry->ret_ip = (unsigned long)ri->ret_addr; |
e09c8614 | 911 | store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); |
413d37d1 | 912 | |
8f8ffe24 | 913 | if (!filter_current_check_discard(buffer, call, entry, event)) |
0d5c6e1c SR |
914 | trace_buffer_unlock_commit_regs(buffer, event, |
915 | irq_flags, pc, regs); | |
413d37d1 MH |
916 | } |
917 | ||
41a7dd42 MH |
918 | static __kprobes void |
919 | kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri, | |
920 | struct pt_regs *regs) | |
921 | { | |
922 | struct ftrace_event_file **file = tp->files; | |
923 | ||
924 | /* Note: preempt is already disabled around the kprobe handler */ | |
925 | while (*file) { | |
926 | __kretprobe_trace_func(tp, ri, regs, *file); | |
927 | file++; | |
928 | } | |
929 | } | |
930 | ||
413d37d1 MH |
931 | /* Event entry printers */ |
932 | enum print_line_t | |
a9a57763 SR |
933 | print_kprobe_event(struct trace_iterator *iter, int flags, |
934 | struct trace_event *event) | |
413d37d1 | 935 | { |
93ccae7a | 936 | struct kprobe_trace_entry_head *field; |
413d37d1 | 937 | struct trace_seq *s = &iter->seq; |
eca0d916 | 938 | struct trace_probe *tp; |
93ccae7a | 939 | u8 *data; |
413d37d1 MH |
940 | int i; |
941 | ||
93ccae7a | 942 | field = (struct kprobe_trace_entry_head *)iter->ent; |
80decc70 | 943 | tp = container_of(event, struct trace_probe, call.event); |
413d37d1 | 944 | |
6e9f23d1 MH |
945 | if (!trace_seq_printf(s, "%s: (", tp->call.name)) |
946 | goto partial; | |
947 | ||
413d37d1 MH |
948 | if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET)) |
949 | goto partial; | |
950 | ||
6e9f23d1 | 951 | if (!trace_seq_puts(s, ")")) |
413d37d1 MH |
952 | goto partial; |
953 | ||
93ccae7a MH |
954 | data = (u8 *)&field[1]; |
955 | for (i = 0; i < tp->nr_args; i++) | |
956 | if (!tp->args[i].type->print(s, tp->args[i].name, | |
e09c8614 | 957 | data + tp->args[i].offset, field)) |
413d37d1 MH |
958 | goto partial; |
959 | ||
960 | if (!trace_seq_puts(s, "\n")) | |
961 | goto partial; | |
962 | ||
963 | return TRACE_TYPE_HANDLED; | |
964 | partial: | |
965 | return TRACE_TYPE_PARTIAL_LINE; | |
966 | } | |
967 | ||
968 | enum print_line_t | |
a9a57763 SR |
969 | print_kretprobe_event(struct trace_iterator *iter, int flags, |
970 | struct trace_event *event) | |
413d37d1 | 971 | { |
93ccae7a | 972 | struct kretprobe_trace_entry_head *field; |
413d37d1 | 973 | struct trace_seq *s = &iter->seq; |
eca0d916 | 974 | struct trace_probe *tp; |
93ccae7a | 975 | u8 *data; |
413d37d1 MH |
976 | int i; |
977 | ||
93ccae7a | 978 | field = (struct kretprobe_trace_entry_head *)iter->ent; |
80decc70 | 979 | tp = container_of(event, struct trace_probe, call.event); |
413d37d1 | 980 | |
6e9f23d1 MH |
981 | if (!trace_seq_printf(s, "%s: (", tp->call.name)) |
982 | goto partial; | |
983 | ||
413d37d1 MH |
984 | if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET)) |
985 | goto partial; | |
986 | ||
987 | if (!trace_seq_puts(s, " <- ")) | |
988 | goto partial; | |
989 | ||
990 | if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET)) | |
991 | goto partial; | |
992 | ||
6e9f23d1 | 993 | if (!trace_seq_puts(s, ")")) |
413d37d1 MH |
994 | goto partial; |
995 | ||
93ccae7a MH |
996 | data = (u8 *)&field[1]; |
997 | for (i = 0; i < tp->nr_args; i++) | |
998 | if (!tp->args[i].type->print(s, tp->args[i].name, | |
e09c8614 | 999 | data + tp->args[i].offset, field)) |
413d37d1 MH |
1000 | goto partial; |
1001 | ||
1002 | if (!trace_seq_puts(s, "\n")) | |
1003 | goto partial; | |
1004 | ||
1005 | return TRACE_TYPE_HANDLED; | |
1006 | partial: | |
1007 | return TRACE_TYPE_PARTIAL_LINE; | |
1008 | } | |
1009 | ||
413d37d1 MH |
1010 | |
1011 | static int kprobe_event_define_fields(struct ftrace_event_call *event_call) | |
1012 | { | |
1013 | int ret, i; | |
93ccae7a | 1014 | struct kprobe_trace_entry_head field; |
413d37d1 MH |
1015 | struct trace_probe *tp = (struct trace_probe *)event_call->data; |
1016 | ||
a703d946 | 1017 | DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0); |
eca0d916 | 1018 | /* Set argument names as fields */ |
93ccae7a | 1019 | for (i = 0; i < tp->nr_args; i++) { |
e09c8614 | 1020 | ret = trace_define_field(event_call, tp->args[i].type->fmttype, |
93ccae7a MH |
1021 | tp->args[i].name, |
1022 | sizeof(field) + tp->args[i].offset, | |
1023 | tp->args[i].type->size, | |
1024 | tp->args[i].type->is_signed, | |
1025 | FILTER_OTHER); | |
1026 | if (ret) | |
1027 | return ret; | |
1028 | } | |
413d37d1 MH |
1029 | return 0; |
1030 | } | |
1031 | ||
1032 | static int kretprobe_event_define_fields(struct ftrace_event_call *event_call) | |
1033 | { | |
1034 | int ret, i; | |
93ccae7a | 1035 | struct kretprobe_trace_entry_head field; |
413d37d1 MH |
1036 | struct trace_probe *tp = (struct trace_probe *)event_call->data; |
1037 | ||
a703d946 MH |
1038 | DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0); |
1039 | DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0); | |
eca0d916 | 1040 | /* Set argument names as fields */ |
93ccae7a | 1041 | for (i = 0; i < tp->nr_args; i++) { |
e09c8614 | 1042 | ret = trace_define_field(event_call, tp->args[i].type->fmttype, |
93ccae7a MH |
1043 | tp->args[i].name, |
1044 | sizeof(field) + tp->args[i].offset, | |
1045 | tp->args[i].type->size, | |
1046 | tp->args[i].type->is_signed, | |
1047 | FILTER_OTHER); | |
1048 | if (ret) | |
1049 | return ret; | |
1050 | } | |
413d37d1 MH |
1051 | return 0; |
1052 | } | |
1053 | ||
a342a028 LJ |
1054 | static int __set_print_fmt(struct trace_probe *tp, char *buf, int len) |
1055 | { | |
1056 | int i; | |
1057 | int pos = 0; | |
1058 | ||
1059 | const char *fmt, *arg; | |
1060 | ||
7143f168 | 1061 | if (!trace_probe_is_return(tp)) { |
a342a028 LJ |
1062 | fmt = "(%lx)"; |
1063 | arg = "REC->" FIELD_STRING_IP; | |
1064 | } else { | |
1065 | fmt = "(%lx <- %lx)"; | |
1066 | arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP; | |
1067 | } | |
1068 | ||
1069 | /* When len=0, we just calculate the needed length */ | |
1070 | #define LEN_OR_ZERO (len ? len - pos : 0) | |
1071 | ||
1072 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt); | |
1073 | ||
1074 | for (i = 0; i < tp->nr_args; i++) { | |
93ccae7a MH |
1075 | pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s", |
1076 | tp->args[i].name, tp->args[i].type->fmt); | |
a342a028 LJ |
1077 | } |
1078 | ||
1079 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg); | |
1080 | ||
1081 | for (i = 0; i < tp->nr_args; i++) { | |
e09c8614 MH |
1082 | if (strcmp(tp->args[i].type->name, "string") == 0) |
1083 | pos += snprintf(buf + pos, LEN_OR_ZERO, | |
1084 | ", __get_str(%s)", | |
1085 | tp->args[i].name); | |
1086 | else | |
1087 | pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s", | |
1088 | tp->args[i].name); | |
a342a028 LJ |
1089 | } |
1090 | ||
1091 | #undef LEN_OR_ZERO | |
1092 | ||
1093 | /* return the length of print_fmt */ | |
1094 | return pos; | |
1095 | } | |
1096 | ||
1097 | static int set_print_fmt(struct trace_probe *tp) | |
1098 | { | |
1099 | int len; | |
1100 | char *print_fmt; | |
1101 | ||
1102 | /* First: called with 0 length to calculate the needed length */ | |
1103 | len = __set_print_fmt(tp, NULL, 0); | |
1104 | print_fmt = kmalloc(len + 1, GFP_KERNEL); | |
1105 | if (!print_fmt) | |
1106 | return -ENOMEM; | |
1107 | ||
1108 | /* Second: actually write the @print_fmt */ | |
1109 | __set_print_fmt(tp, print_fmt, len + 1); | |
1110 | tp->call.print_fmt = print_fmt; | |
1111 | ||
1112 | return 0; | |
1113 | } | |
1114 | ||
07b139c8 | 1115 | #ifdef CONFIG_PERF_EVENTS |
e08d1c65 MH |
1116 | |
1117 | /* Kprobe profile handler */ | |
2b106aab MH |
1118 | static __kprobes void |
1119 | kprobe_perf_func(struct trace_probe *tp, struct pt_regs *regs) | |
e08d1c65 | 1120 | { |
e08d1c65 | 1121 | struct ftrace_event_call *call = &tp->call; |
93ccae7a | 1122 | struct kprobe_trace_entry_head *entry; |
1c024eca | 1123 | struct hlist_head *head; |
e09c8614 | 1124 | int size, __size, dsize; |
4ed7c92d | 1125 | int rctx; |
e08d1c65 | 1126 | |
e09c8614 MH |
1127 | dsize = __get_data_size(tp, regs); |
1128 | __size = sizeof(*entry) + tp->size + dsize; | |
74ebb63e MH |
1129 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
1130 | size -= sizeof(u32); | |
97d5a220 | 1131 | if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, |
a1a138d0 | 1132 | "profile buffer not large enough")) |
1e12a4a7 | 1133 | return; |
ce71b9df | 1134 | |
ff5f149b | 1135 | entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx); |
430ad5a6 | 1136 | if (!entry) |
1e12a4a7 | 1137 | return; |
a1a138d0 | 1138 | |
2b106aab | 1139 | entry->ip = (unsigned long)tp->rp.kp.addr; |
e09c8614 MH |
1140 | memset(&entry[1], 0, dsize); |
1141 | store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); | |
444a2a3b | 1142 | |
3771f077 | 1143 | head = this_cpu_ptr(call->perf_events); |
e6dab5ff AV |
1144 | perf_trace_buf_submit(entry, size, rctx, |
1145 | entry->ip, 1, regs, head, NULL); | |
e08d1c65 MH |
1146 | } |
1147 | ||
1148 | /* Kretprobe profile handler */ | |
2b106aab MH |
1149 | static __kprobes void |
1150 | kretprobe_perf_func(struct trace_probe *tp, struct kretprobe_instance *ri, | |
1151 | struct pt_regs *regs) | |
e08d1c65 | 1152 | { |
e08d1c65 | 1153 | struct ftrace_event_call *call = &tp->call; |
93ccae7a | 1154 | struct kretprobe_trace_entry_head *entry; |
1c024eca | 1155 | struct hlist_head *head; |
e09c8614 | 1156 | int size, __size, dsize; |
4ed7c92d | 1157 | int rctx; |
e08d1c65 | 1158 | |
e09c8614 MH |
1159 | dsize = __get_data_size(tp, regs); |
1160 | __size = sizeof(*entry) + tp->size + dsize; | |
74ebb63e MH |
1161 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
1162 | size -= sizeof(u32); | |
97d5a220 | 1163 | if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, |
a1a138d0 | 1164 | "profile buffer not large enough")) |
1e12a4a7 | 1165 | return; |
444a2a3b | 1166 | |
ff5f149b | 1167 | entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx); |
430ad5a6 | 1168 | if (!entry) |
1e12a4a7 | 1169 | return; |
e08d1c65 | 1170 | |
a1a138d0 MH |
1171 | entry->func = (unsigned long)tp->rp.kp.addr; |
1172 | entry->ret_ip = (unsigned long)ri->ret_addr; | |
e09c8614 | 1173 | store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); |
444a2a3b | 1174 | |
3771f077 | 1175 | head = this_cpu_ptr(call->perf_events); |
e6dab5ff AV |
1176 | perf_trace_buf_submit(entry, size, rctx, |
1177 | entry->ret_ip, 1, regs, head, NULL); | |
e08d1c65 | 1178 | } |
07b139c8 | 1179 | #endif /* CONFIG_PERF_EVENTS */ |
50d78056 | 1180 | |
2239291a | 1181 | static __kprobes |
ceec0b6f JO |
1182 | int kprobe_register(struct ftrace_event_call *event, |
1183 | enum trace_reg type, void *data) | |
2239291a | 1184 | { |
1538f888 | 1185 | struct trace_probe *tp = (struct trace_probe *)event->data; |
41a7dd42 | 1186 | struct ftrace_event_file *file = data; |
1538f888 | 1187 | |
2239291a SR |
1188 | switch (type) { |
1189 | case TRACE_REG_REGISTER: | |
41a7dd42 | 1190 | return enable_trace_probe(tp, file); |
2239291a | 1191 | case TRACE_REG_UNREGISTER: |
41a7dd42 | 1192 | return disable_trace_probe(tp, file); |
2239291a SR |
1193 | |
1194 | #ifdef CONFIG_PERF_EVENTS | |
1195 | case TRACE_REG_PERF_REGISTER: | |
41a7dd42 | 1196 | return enable_trace_probe(tp, NULL); |
2239291a | 1197 | case TRACE_REG_PERF_UNREGISTER: |
41a7dd42 | 1198 | return disable_trace_probe(tp, NULL); |
ceec0b6f JO |
1199 | case TRACE_REG_PERF_OPEN: |
1200 | case TRACE_REG_PERF_CLOSE: | |
489c75c3 JO |
1201 | case TRACE_REG_PERF_ADD: |
1202 | case TRACE_REG_PERF_DEL: | |
ceec0b6f | 1203 | return 0; |
2239291a SR |
1204 | #endif |
1205 | } | |
1206 | return 0; | |
1207 | } | |
50d78056 MH |
1208 | |
1209 | static __kprobes | |
1210 | int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) | |
1211 | { | |
1212 | struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); | |
e08d1c65 | 1213 | |
48182bd2 MH |
1214 | tp->nhit++; |
1215 | ||
50d78056 | 1216 | if (tp->flags & TP_FLAG_TRACE) |
2b106aab | 1217 | kprobe_trace_func(tp, regs); |
07b139c8 | 1218 | #ifdef CONFIG_PERF_EVENTS |
50d78056 | 1219 | if (tp->flags & TP_FLAG_PROFILE) |
2b106aab | 1220 | kprobe_perf_func(tp, regs); |
07b139c8 | 1221 | #endif |
50d78056 MH |
1222 | return 0; /* We don't tweek kernel, so just return 0 */ |
1223 | } | |
1224 | ||
1225 | static __kprobes | |
1226 | int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs) | |
1227 | { | |
1228 | struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); | |
1229 | ||
48182bd2 MH |
1230 | tp->nhit++; |
1231 | ||
50d78056 | 1232 | if (tp->flags & TP_FLAG_TRACE) |
2b106aab | 1233 | kretprobe_trace_func(tp, ri, regs); |
07b139c8 | 1234 | #ifdef CONFIG_PERF_EVENTS |
50d78056 | 1235 | if (tp->flags & TP_FLAG_PROFILE) |
2b106aab | 1236 | kretprobe_perf_func(tp, ri, regs); |
07b139c8 | 1237 | #endif |
50d78056 MH |
1238 | return 0; /* We don't tweek kernel, so just return 0 */ |
1239 | } | |
e08d1c65 | 1240 | |
a9a57763 SR |
1241 | static struct trace_event_functions kretprobe_funcs = { |
1242 | .trace = print_kretprobe_event | |
1243 | }; | |
1244 | ||
1245 | static struct trace_event_functions kprobe_funcs = { | |
1246 | .trace = print_kprobe_event | |
1247 | }; | |
1248 | ||
413d37d1 MH |
1249 | static int register_probe_event(struct trace_probe *tp) |
1250 | { | |
1251 | struct ftrace_event_call *call = &tp->call; | |
1252 | int ret; | |
1253 | ||
1254 | /* Initialize ftrace_event_call */ | |
ffb9f995 | 1255 | INIT_LIST_HEAD(&call->class->fields); |
7143f168 | 1256 | if (trace_probe_is_return(tp)) { |
80decc70 | 1257 | call->event.funcs = &kretprobe_funcs; |
2e33af02 | 1258 | call->class->define_fields = kretprobe_event_define_fields; |
413d37d1 | 1259 | } else { |
80decc70 | 1260 | call->event.funcs = &kprobe_funcs; |
2e33af02 | 1261 | call->class->define_fields = kprobe_event_define_fields; |
413d37d1 | 1262 | } |
a342a028 LJ |
1263 | if (set_print_fmt(tp) < 0) |
1264 | return -ENOMEM; | |
32c0edae SR |
1265 | ret = register_ftrace_event(&call->event); |
1266 | if (!ret) { | |
a342a028 | 1267 | kfree(call->print_fmt); |
ff50d991 | 1268 | return -ENODEV; |
a342a028 | 1269 | } |
553552ce | 1270 | call->flags = 0; |
2239291a | 1271 | call->class->reg = kprobe_register; |
413d37d1 MH |
1272 | call->data = tp; |
1273 | ret = trace_add_event_call(call); | |
ff50d991 | 1274 | if (ret) { |
413d37d1 | 1275 | pr_info("Failed to register kprobe event: %s\n", call->name); |
a342a028 | 1276 | kfree(call->print_fmt); |
80decc70 | 1277 | unregister_ftrace_event(&call->event); |
ff50d991 | 1278 | } |
413d37d1 MH |
1279 | return ret; |
1280 | } | |
1281 | ||
1282 | static void unregister_probe_event(struct trace_probe *tp) | |
1283 | { | |
ff50d991 | 1284 | /* tp->event is unregistered in trace_remove_event_call() */ |
413d37d1 | 1285 | trace_remove_event_call(&tp->call); |
a342a028 | 1286 | kfree(tp->call.print_fmt); |
413d37d1 MH |
1287 | } |
1288 | ||
25985edc | 1289 | /* Make a debugfs interface for controlling probe points */ |
413d37d1 MH |
1290 | static __init int init_kprobe_trace(void) |
1291 | { | |
1292 | struct dentry *d_tracer; | |
1293 | struct dentry *entry; | |
413d37d1 | 1294 | |
61424318 MH |
1295 | if (register_module_notifier(&trace_probe_module_nb)) |
1296 | return -EINVAL; | |
1297 | ||
413d37d1 MH |
1298 | d_tracer = tracing_init_dentry(); |
1299 | if (!d_tracer) | |
1300 | return 0; | |
1301 | ||
1302 | entry = debugfs_create_file("kprobe_events", 0644, d_tracer, | |
1303 | NULL, &kprobe_events_ops); | |
1304 | ||
cd7e7bd5 | 1305 | /* Event list interface */ |
413d37d1 MH |
1306 | if (!entry) |
1307 | pr_warning("Could not create debugfs " | |
1308 | "'kprobe_events' entry\n"); | |
cd7e7bd5 MH |
1309 | |
1310 | /* Profile interface */ | |
1311 | entry = debugfs_create_file("kprobe_profile", 0444, d_tracer, | |
1312 | NULL, &kprobe_profile_ops); | |
1313 | ||
1314 | if (!entry) | |
1315 | pr_warning("Could not create debugfs " | |
1316 | "'kprobe_profile' entry\n"); | |
413d37d1 MH |
1317 | return 0; |
1318 | } | |
1319 | fs_initcall(init_kprobe_trace); | |
1320 | ||
1321 | ||
1322 | #ifdef CONFIG_FTRACE_STARTUP_TEST | |
1323 | ||
265a5b7e SR |
1324 | /* |
1325 | * The "__used" keeps gcc from removing the function symbol | |
1326 | * from the kallsyms table. | |
1327 | */ | |
1328 | static __used int kprobe_trace_selftest_target(int a1, int a2, int a3, | |
1329 | int a4, int a5, int a6) | |
413d37d1 MH |
1330 | { |
1331 | return a1 + a2 + a3 + a4 + a5 + a6; | |
1332 | } | |
1333 | ||
41a7dd42 MH |
1334 | static struct ftrace_event_file * |
1335 | find_trace_probe_file(struct trace_probe *tp, struct trace_array *tr) | |
1336 | { | |
1337 | struct ftrace_event_file *file; | |
1338 | ||
1339 | list_for_each_entry(file, &tr->events, list) | |
1340 | if (file->event_call == &tp->call) | |
1341 | return file; | |
1342 | ||
1343 | return NULL; | |
1344 | } | |
1345 | ||
413d37d1 MH |
1346 | static __init int kprobe_trace_self_tests_init(void) |
1347 | { | |
231e36f4 | 1348 | int ret, warn = 0; |
413d37d1 | 1349 | int (*target)(int, int, int, int, int, int); |
231e36f4 | 1350 | struct trace_probe *tp; |
41a7dd42 | 1351 | struct ftrace_event_file *file; |
413d37d1 MH |
1352 | |
1353 | target = kprobe_trace_selftest_target; | |
1354 | ||
1355 | pr_info("Testing kprobe tracing: "); | |
1356 | ||
8ab83f56 SD |
1357 | ret = traceprobe_command("p:testprobe kprobe_trace_selftest_target " |
1358 | "$stack $stack0 +0($stack)", | |
1359 | create_trace_probe); | |
231e36f4 | 1360 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 1361 | pr_warn("error on probing function entry.\n"); |
231e36f4 MH |
1362 | warn++; |
1363 | } else { | |
1364 | /* Enable trace point */ | |
7143f168 | 1365 | tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM); |
231e36f4 | 1366 | if (WARN_ON_ONCE(tp == NULL)) { |
41a7dd42 | 1367 | pr_warn("error on getting new probe.\n"); |
231e36f4 | 1368 | warn++; |
41a7dd42 MH |
1369 | } else { |
1370 | file = find_trace_probe_file(tp, top_trace_array()); | |
1371 | if (WARN_ON_ONCE(file == NULL)) { | |
1372 | pr_warn("error on getting probe file.\n"); | |
1373 | warn++; | |
1374 | } else | |
1375 | enable_trace_probe(tp, file); | |
1376 | } | |
231e36f4 | 1377 | } |
413d37d1 | 1378 | |
8ab83f56 SD |
1379 | ret = traceprobe_command("r:testprobe2 kprobe_trace_selftest_target " |
1380 | "$retval", create_trace_probe); | |
231e36f4 | 1381 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 1382 | pr_warn("error on probing function return.\n"); |
231e36f4 MH |
1383 | warn++; |
1384 | } else { | |
1385 | /* Enable trace point */ | |
7143f168 | 1386 | tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM); |
231e36f4 | 1387 | if (WARN_ON_ONCE(tp == NULL)) { |
41a7dd42 | 1388 | pr_warn("error on getting 2nd new probe.\n"); |
231e36f4 | 1389 | warn++; |
41a7dd42 MH |
1390 | } else { |
1391 | file = find_trace_probe_file(tp, top_trace_array()); | |
1392 | if (WARN_ON_ONCE(file == NULL)) { | |
1393 | pr_warn("error on getting probe file.\n"); | |
1394 | warn++; | |
1395 | } else | |
1396 | enable_trace_probe(tp, file); | |
1397 | } | |
231e36f4 MH |
1398 | } |
1399 | ||
1400 | if (warn) | |
1401 | goto end; | |
413d37d1 MH |
1402 | |
1403 | ret = target(1, 2, 3, 4, 5, 6); | |
1404 | ||
02ca1521 MH |
1405 | /* Disable trace points before removing it */ |
1406 | tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM); | |
1407 | if (WARN_ON_ONCE(tp == NULL)) { | |
41a7dd42 | 1408 | pr_warn("error on getting test probe.\n"); |
02ca1521 | 1409 | warn++; |
41a7dd42 MH |
1410 | } else { |
1411 | file = find_trace_probe_file(tp, top_trace_array()); | |
1412 | if (WARN_ON_ONCE(file == NULL)) { | |
1413 | pr_warn("error on getting probe file.\n"); | |
1414 | warn++; | |
1415 | } else | |
1416 | disable_trace_probe(tp, file); | |
1417 | } | |
02ca1521 MH |
1418 | |
1419 | tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM); | |
1420 | if (WARN_ON_ONCE(tp == NULL)) { | |
41a7dd42 | 1421 | pr_warn("error on getting 2nd test probe.\n"); |
02ca1521 | 1422 | warn++; |
41a7dd42 MH |
1423 | } else { |
1424 | file = find_trace_probe_file(tp, top_trace_array()); | |
1425 | if (WARN_ON_ONCE(file == NULL)) { | |
1426 | pr_warn("error on getting probe file.\n"); | |
1427 | warn++; | |
1428 | } else | |
1429 | disable_trace_probe(tp, file); | |
1430 | } | |
02ca1521 | 1431 | |
8ab83f56 | 1432 | ret = traceprobe_command("-:testprobe", create_trace_probe); |
231e36f4 | 1433 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 1434 | pr_warn("error on deleting a probe.\n"); |
231e36f4 MH |
1435 | warn++; |
1436 | } | |
1437 | ||
8ab83f56 | 1438 | ret = traceprobe_command("-:testprobe2", create_trace_probe); |
231e36f4 | 1439 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 1440 | pr_warn("error on deleting a probe.\n"); |
231e36f4 MH |
1441 | warn++; |
1442 | } | |
413d37d1 | 1443 | |
231e36f4 | 1444 | end: |
7143f168 | 1445 | release_all_trace_probes(); |
231e36f4 MH |
1446 | if (warn) |
1447 | pr_cont("NG: Some tests are failed. Please check them.\n"); | |
1448 | else | |
1449 | pr_cont("OK\n"); | |
413d37d1 MH |
1450 | return 0; |
1451 | } | |
1452 | ||
1453 | late_initcall(kprobe_trace_self_tests_init); | |
1454 | ||
1455 | #endif |