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 | */ |
c31ffb3f | 30 | struct trace_kprobe { |
413d37d1 | 31 | struct list_head list; |
4a846b44 | 32 | struct kretprobe rp; /* Use rp.kp for kprobe use */ |
a7636d9e | 33 | unsigned long __percpu *nhit; |
413d37d1 | 34 | const char *symbol; /* symbol name */ |
c31ffb3f | 35 | struct trace_probe tp; |
413d37d1 MH |
36 | }; |
37 | ||
c31ffb3f NK |
38 | #define SIZEOF_TRACE_KPROBE(n) \ |
39 | (offsetof(struct trace_kprobe, tp.args) + \ | |
eca0d916 | 40 | (sizeof(struct probe_arg) * (n))) |
a82378d8 | 41 | |
93ccae7a | 42 | |
3da0f180 | 43 | static nokprobe_inline bool trace_kprobe_is_return(struct trace_kprobe *tk) |
413d37d1 | 44 | { |
c31ffb3f | 45 | return tk->rp.handler != NULL; |
413d37d1 MH |
46 | } |
47 | ||
3da0f180 | 48 | static nokprobe_inline const char *trace_kprobe_symbol(struct trace_kprobe *tk) |
413d37d1 | 49 | { |
c31ffb3f | 50 | return tk->symbol ? tk->symbol : "unknown"; |
413d37d1 MH |
51 | } |
52 | ||
3da0f180 | 53 | static nokprobe_inline unsigned long trace_kprobe_offset(struct trace_kprobe *tk) |
61424318 | 54 | { |
c31ffb3f | 55 | return tk->rp.kp.offset; |
61424318 MH |
56 | } |
57 | ||
3da0f180 | 58 | static nokprobe_inline bool trace_kprobe_has_gone(struct trace_kprobe *tk) |
61424318 | 59 | { |
c31ffb3f | 60 | return !!(kprobe_gone(&tk->rp.kp)); |
61424318 MH |
61 | } |
62 | ||
3da0f180 | 63 | static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk, |
c31ffb3f | 64 | struct module *mod) |
61424318 MH |
65 | { |
66 | int len = strlen(mod->name); | |
c31ffb3f | 67 | const char *name = trace_kprobe_symbol(tk); |
61424318 MH |
68 | return strncmp(mod->name, name, len) == 0 && name[len] == ':'; |
69 | } | |
70 | ||
3da0f180 | 71 | static nokprobe_inline bool trace_kprobe_is_on_module(struct trace_kprobe *tk) |
61424318 | 72 | { |
c31ffb3f | 73 | return !!strchr(trace_kprobe_symbol(tk), ':'); |
61424318 MH |
74 | } |
75 | ||
f18f97ac MN |
76 | static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe *tk) |
77 | { | |
78 | unsigned long nhit = 0; | |
79 | int cpu; | |
80 | ||
81 | for_each_possible_cpu(cpu) | |
82 | nhit += *per_cpu_ptr(tk->nhit, cpu); | |
83 | ||
84 | return nhit; | |
85 | } | |
86 | ||
c31ffb3f NK |
87 | static int register_kprobe_event(struct trace_kprobe *tk); |
88 | static int unregister_kprobe_event(struct trace_kprobe *tk); | |
413d37d1 MH |
89 | |
90 | static DEFINE_MUTEX(probe_lock); | |
91 | static LIST_HEAD(probe_list); | |
92 | ||
50d78056 MH |
93 | static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs); |
94 | static int kretprobe_dispatcher(struct kretprobe_instance *ri, | |
95 | struct pt_regs *regs); | |
96 | ||
1301a44e NK |
97 | /* Memory fetching by symbol */ |
98 | struct symbol_cache { | |
99 | char *symbol; | |
100 | long offset; | |
101 | unsigned long addr; | |
102 | }; | |
103 | ||
104 | unsigned long update_symbol_cache(struct symbol_cache *sc) | |
105 | { | |
106 | sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol); | |
107 | ||
108 | if (sc->addr) | |
109 | sc->addr += sc->offset; | |
110 | ||
111 | return sc->addr; | |
112 | } | |
113 | ||
114 | void free_symbol_cache(struct symbol_cache *sc) | |
115 | { | |
116 | kfree(sc->symbol); | |
117 | kfree(sc); | |
118 | } | |
119 | ||
120 | struct symbol_cache *alloc_symbol_cache(const char *sym, long offset) | |
121 | { | |
122 | struct symbol_cache *sc; | |
123 | ||
124 | if (!sym || strlen(sym) == 0) | |
125 | return NULL; | |
126 | ||
127 | sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL); | |
128 | if (!sc) | |
129 | return NULL; | |
130 | ||
131 | sc->symbol = kstrdup(sym, GFP_KERNEL); | |
132 | if (!sc->symbol) { | |
133 | kfree(sc); | |
134 | return NULL; | |
135 | } | |
136 | sc->offset = offset; | |
137 | update_symbol_cache(sc); | |
138 | ||
139 | return sc; | |
140 | } | |
141 | ||
3fd996a2 NK |
142 | /* |
143 | * Kprobes-specific fetch functions | |
144 | */ | |
145 | #define DEFINE_FETCH_stack(type) \ | |
3da0f180 | 146 | static void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs, \ |
3fd996a2 NK |
147 | void *offset, void *dest) \ |
148 | { \ | |
149 | *(type *)dest = (type)regs_get_kernel_stack_nth(regs, \ | |
150 | (unsigned int)((unsigned long)offset)); \ | |
3da0f180 MH |
151 | } \ |
152 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(stack, type)); | |
153 | ||
3fd996a2 NK |
154 | DEFINE_BASIC_FETCH_FUNCS(stack) |
155 | /* No string on the stack entry */ | |
156 | #define fetch_stack_string NULL | |
157 | #define fetch_stack_string_size NULL | |
158 | ||
5baaa59e | 159 | #define DEFINE_FETCH_memory(type) \ |
3da0f180 | 160 | static void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs, \ |
5baaa59e NK |
161 | void *addr, void *dest) \ |
162 | { \ | |
163 | type retval; \ | |
164 | if (probe_kernel_address(addr, retval)) \ | |
165 | *(type *)dest = 0; \ | |
166 | else \ | |
167 | *(type *)dest = retval; \ | |
3da0f180 MH |
168 | } \ |
169 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(memory, type)); | |
170 | ||
5baaa59e NK |
171 | DEFINE_BASIC_FETCH_FUNCS(memory) |
172 | /* | |
173 | * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max | |
174 | * length and relative data location. | |
175 | */ | |
3da0f180 MH |
176 | static void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs, |
177 | void *addr, void *dest) | |
5baaa59e | 178 | { |
5baaa59e NK |
179 | int maxlen = get_rloc_len(*(u32 *)dest); |
180 | u8 *dst = get_rloc_data(dest); | |
1a6877b9 | 181 | long ret; |
5baaa59e NK |
182 | |
183 | if (!maxlen) | |
184 | return; | |
185 | ||
186 | /* | |
187 | * Try to get string again, since the string can be changed while | |
188 | * probing. | |
189 | */ | |
1a6877b9 | 190 | ret = strncpy_from_unsafe(dst, addr, maxlen); |
5baaa59e NK |
191 | |
192 | if (ret < 0) { /* Failed to fetch string */ | |
1a6877b9 | 193 | dst[0] = '\0'; |
5baaa59e NK |
194 | *(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest)); |
195 | } else { | |
1a6877b9 | 196 | *(u32 *)dest = make_data_rloc(ret, get_rloc_offs(*(u32 *)dest)); |
5baaa59e NK |
197 | } |
198 | } | |
3da0f180 | 199 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(memory, string)); |
5baaa59e NK |
200 | |
201 | /* Return the length of string -- including null terminal byte */ | |
3da0f180 MH |
202 | static void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs, |
203 | void *addr, void *dest) | |
5baaa59e NK |
204 | { |
205 | mm_segment_t old_fs; | |
206 | int ret, len = 0; | |
207 | u8 c; | |
208 | ||
209 | old_fs = get_fs(); | |
210 | set_fs(KERNEL_DS); | |
211 | pagefault_disable(); | |
212 | ||
213 | do { | |
214 | ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1); | |
215 | len++; | |
216 | } while (c && ret == 0 && len < MAX_STRING_SIZE); | |
217 | ||
218 | pagefault_enable(); | |
219 | set_fs(old_fs); | |
220 | ||
221 | if (ret < 0) /* Failed to check the length */ | |
222 | *(u32 *)dest = 0; | |
223 | else | |
224 | *(u32 *)dest = len; | |
225 | } | |
3da0f180 | 226 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(memory, string_size)); |
5baaa59e | 227 | |
1301a44e | 228 | #define DEFINE_FETCH_symbol(type) \ |
3da0f180 | 229 | void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs, void *data, void *dest)\ |
1301a44e NK |
230 | { \ |
231 | struct symbol_cache *sc = data; \ | |
232 | if (sc->addr) \ | |
233 | fetch_memory_##type(regs, (void *)sc->addr, dest); \ | |
234 | else \ | |
235 | *(type *)dest = 0; \ | |
3da0f180 MH |
236 | } \ |
237 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(symbol, type)); | |
238 | ||
1301a44e NK |
239 | DEFINE_BASIC_FETCH_FUNCS(symbol) |
240 | DEFINE_FETCH_symbol(string) | |
241 | DEFINE_FETCH_symbol(string_size) | |
242 | ||
b7e0bf34 NK |
243 | /* kprobes don't support file_offset fetch methods */ |
244 | #define fetch_file_offset_u8 NULL | |
245 | #define fetch_file_offset_u16 NULL | |
246 | #define fetch_file_offset_u32 NULL | |
247 | #define fetch_file_offset_u64 NULL | |
248 | #define fetch_file_offset_string NULL | |
249 | #define fetch_file_offset_string_size NULL | |
250 | ||
34fee3a1 | 251 | /* Fetch type information table */ |
d9a16d3a | 252 | static const struct fetch_type kprobes_fetch_type_table[] = { |
34fee3a1 NK |
253 | /* Special types */ |
254 | [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string, | |
255 | sizeof(u32), 1, "__data_loc char[]"), | |
256 | [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32, | |
257 | string_size, sizeof(u32), 0, "u32"), | |
258 | /* Basic types */ | |
259 | ASSIGN_FETCH_TYPE(u8, u8, 0), | |
260 | ASSIGN_FETCH_TYPE(u16, u16, 0), | |
261 | ASSIGN_FETCH_TYPE(u32, u32, 0), | |
262 | ASSIGN_FETCH_TYPE(u64, u64, 0), | |
263 | ASSIGN_FETCH_TYPE(s8, u8, 1), | |
264 | ASSIGN_FETCH_TYPE(s16, u16, 1), | |
265 | ASSIGN_FETCH_TYPE(s32, u32, 1), | |
266 | ASSIGN_FETCH_TYPE(s64, u64, 1), | |
17ce3dc7 MH |
267 | ASSIGN_FETCH_TYPE_ALIAS(x8, u8, u8, 0), |
268 | ASSIGN_FETCH_TYPE_ALIAS(x16, u16, u16, 0), | |
269 | ASSIGN_FETCH_TYPE_ALIAS(x32, u32, u32, 0), | |
270 | ASSIGN_FETCH_TYPE_ALIAS(x64, u64, u64, 0), | |
34fee3a1 NK |
271 | |
272 | ASSIGN_FETCH_TYPE_END | |
273 | }; | |
274 | ||
4a846b44 MH |
275 | /* |
276 | * Allocate new trace_probe and initialize it (including kprobes). | |
277 | */ | |
c31ffb3f | 278 | static struct trace_kprobe *alloc_trace_kprobe(const char *group, |
f52487e9 | 279 | const char *event, |
4a846b44 MH |
280 | void *addr, |
281 | const char *symbol, | |
282 | unsigned long offs, | |
3a6b7666 | 283 | int nargs, bool is_return) |
413d37d1 | 284 | { |
c31ffb3f | 285 | struct trace_kprobe *tk; |
6f3cf440 | 286 | int ret = -ENOMEM; |
413d37d1 | 287 | |
c31ffb3f NK |
288 | tk = kzalloc(SIZEOF_TRACE_KPROBE(nargs), GFP_KERNEL); |
289 | if (!tk) | |
6f3cf440 | 290 | return ERR_PTR(ret); |
413d37d1 | 291 | |
a7636d9e MKL |
292 | tk->nhit = alloc_percpu(unsigned long); |
293 | if (!tk->nhit) | |
294 | goto error; | |
295 | ||
413d37d1 | 296 | if (symbol) { |
c31ffb3f NK |
297 | tk->symbol = kstrdup(symbol, GFP_KERNEL); |
298 | if (!tk->symbol) | |
413d37d1 | 299 | goto error; |
c31ffb3f NK |
300 | tk->rp.kp.symbol_name = tk->symbol; |
301 | tk->rp.kp.offset = offs; | |
4a846b44 | 302 | } else |
c31ffb3f | 303 | tk->rp.kp.addr = addr; |
4a846b44 MH |
304 | |
305 | if (is_return) | |
c31ffb3f | 306 | tk->rp.handler = kretprobe_dispatcher; |
4a846b44 | 307 | else |
c31ffb3f | 308 | tk->rp.kp.pre_handler = kprobe_dispatcher; |
4a846b44 | 309 | |
da34634f | 310 | if (!event || !is_good_name(event)) { |
6f3cf440 | 311 | ret = -EINVAL; |
4263565d | 312 | goto error; |
6f3cf440 MH |
313 | } |
314 | ||
c31ffb3f NK |
315 | tk->tp.call.class = &tk->tp.class; |
316 | tk->tp.call.name = kstrdup(event, GFP_KERNEL); | |
317 | if (!tk->tp.call.name) | |
4263565d | 318 | goto error; |
413d37d1 | 319 | |
da34634f | 320 | if (!group || !is_good_name(group)) { |
6f3cf440 | 321 | ret = -EINVAL; |
f52487e9 | 322 | goto error; |
6f3cf440 MH |
323 | } |
324 | ||
c31ffb3f NK |
325 | tk->tp.class.system = kstrdup(group, GFP_KERNEL); |
326 | if (!tk->tp.class.system) | |
f52487e9 MH |
327 | goto error; |
328 | ||
c31ffb3f NK |
329 | INIT_LIST_HEAD(&tk->list); |
330 | INIT_LIST_HEAD(&tk->tp.files); | |
331 | return tk; | |
413d37d1 | 332 | error: |
c31ffb3f NK |
333 | kfree(tk->tp.call.name); |
334 | kfree(tk->symbol); | |
a7636d9e | 335 | free_percpu(tk->nhit); |
c31ffb3f | 336 | kfree(tk); |
6f3cf440 | 337 | return ERR_PTR(ret); |
413d37d1 MH |
338 | } |
339 | ||
c31ffb3f | 340 | static void free_trace_kprobe(struct trace_kprobe *tk) |
413d37d1 MH |
341 | { |
342 | int i; | |
343 | ||
c31ffb3f NK |
344 | for (i = 0; i < tk->tp.nr_args; i++) |
345 | traceprobe_free_probe_arg(&tk->tp.args[i]); | |
413d37d1 | 346 | |
c31ffb3f NK |
347 | kfree(tk->tp.call.class->system); |
348 | kfree(tk->tp.call.name); | |
349 | kfree(tk->symbol); | |
a7636d9e | 350 | free_percpu(tk->nhit); |
c31ffb3f | 351 | kfree(tk); |
413d37d1 MH |
352 | } |
353 | ||
c31ffb3f NK |
354 | static struct trace_kprobe *find_trace_kprobe(const char *event, |
355 | const char *group) | |
413d37d1 | 356 | { |
c31ffb3f | 357 | struct trace_kprobe *tk; |
413d37d1 | 358 | |
c31ffb3f | 359 | list_for_each_entry(tk, &probe_list, list) |
687fcc4a | 360 | if (strcmp(trace_event_name(&tk->tp.call), event) == 0 && |
c31ffb3f NK |
361 | strcmp(tk->tp.call.class->system, group) == 0) |
362 | return tk; | |
413d37d1 MH |
363 | return NULL; |
364 | } | |
365 | ||
41a7dd42 MH |
366 | /* |
367 | * Enable trace_probe | |
368 | * if the file is NULL, enable "perf" handler, or enable "trace" handler. | |
369 | */ | |
370 | static int | |
7f1d2f82 | 371 | enable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file) |
1538f888 MH |
372 | { |
373 | int ret = 0; | |
374 | ||
41a7dd42 | 375 | if (file) { |
b04d52e3 ON |
376 | struct event_file_link *link; |
377 | ||
378 | link = kmalloc(sizeof(*link), GFP_KERNEL); | |
379 | if (!link) { | |
41a7dd42 | 380 | ret = -ENOMEM; |
3fe3d619 | 381 | goto out; |
41a7dd42 | 382 | } |
41a7dd42 | 383 | |
b04d52e3 | 384 | link->file = file; |
c31ffb3f | 385 | list_add_tail_rcu(&link->list, &tk->tp.files); |
41a7dd42 | 386 | |
c31ffb3f | 387 | tk->tp.flags |= TP_FLAG_TRACE; |
41a7dd42 | 388 | } else |
c31ffb3f | 389 | tk->tp.flags |= TP_FLAG_PROFILE; |
41a7dd42 | 390 | |
c31ffb3f NK |
391 | if (trace_probe_is_registered(&tk->tp) && !trace_kprobe_has_gone(tk)) { |
392 | if (trace_kprobe_is_return(tk)) | |
393 | ret = enable_kretprobe(&tk->rp); | |
1538f888 | 394 | else |
c31ffb3f | 395 | ret = enable_kprobe(&tk->rp.kp); |
1538f888 | 396 | } |
3fe3d619 | 397 | out: |
1538f888 MH |
398 | return ret; |
399 | } | |
400 | ||
41a7dd42 MH |
401 | /* |
402 | * Disable trace_probe | |
403 | * if the file is NULL, disable "perf" handler, or disable "trace" handler. | |
404 | */ | |
405 | static int | |
7f1d2f82 | 406 | disable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file) |
1538f888 | 407 | { |
a232e270 MH |
408 | struct event_file_link *link = NULL; |
409 | int wait = 0; | |
41a7dd42 MH |
410 | int ret = 0; |
411 | ||
41a7dd42 | 412 | if (file) { |
c31ffb3f | 413 | link = find_event_file_link(&tk->tp, file); |
b04d52e3 | 414 | if (!link) { |
41a7dd42 | 415 | ret = -EINVAL; |
3fe3d619 | 416 | goto out; |
41a7dd42 MH |
417 | } |
418 | ||
b04d52e3 | 419 | list_del_rcu(&link->list); |
a232e270 | 420 | wait = 1; |
c31ffb3f | 421 | if (!list_empty(&tk->tp.files)) |
b04d52e3 | 422 | goto out; |
41a7dd42 | 423 | |
c31ffb3f | 424 | tk->tp.flags &= ~TP_FLAG_TRACE; |
41a7dd42 | 425 | } else |
c31ffb3f | 426 | tk->tp.flags &= ~TP_FLAG_PROFILE; |
41a7dd42 | 427 | |
c31ffb3f NK |
428 | if (!trace_probe_is_enabled(&tk->tp) && trace_probe_is_registered(&tk->tp)) { |
429 | if (trace_kprobe_is_return(tk)) | |
430 | disable_kretprobe(&tk->rp); | |
1538f888 | 431 | else |
c31ffb3f | 432 | disable_kprobe(&tk->rp.kp); |
a232e270 | 433 | wait = 1; |
1538f888 | 434 | } |
3fe3d619 | 435 | out: |
a232e270 MH |
436 | if (wait) { |
437 | /* | |
438 | * Synchronize with kprobe_trace_func/kretprobe_trace_func | |
439 | * to ensure disabled (all running handlers are finished). | |
440 | * This is not only for kfree(), but also the caller, | |
441 | * trace_remove_event_call() supposes it for releasing | |
442 | * event_call related objects, which will be accessed in | |
443 | * the kprobe_trace_func/kretprobe_trace_func. | |
444 | */ | |
445 | synchronize_sched(); | |
446 | kfree(link); /* Ignored if link == NULL */ | |
447 | } | |
448 | ||
41a7dd42 | 449 | return ret; |
1538f888 MH |
450 | } |
451 | ||
61424318 | 452 | /* Internal register function - just handle k*probes and flags */ |
c31ffb3f | 453 | static int __register_trace_kprobe(struct trace_kprobe *tk) |
413d37d1 | 454 | { |
7f6878a3 | 455 | int i, ret; |
61424318 | 456 | |
c31ffb3f | 457 | if (trace_probe_is_registered(&tk->tp)) |
61424318 MH |
458 | return -EINVAL; |
459 | ||
c31ffb3f NK |
460 | for (i = 0; i < tk->tp.nr_args; i++) |
461 | traceprobe_update_arg(&tk->tp.args[i]); | |
7f6878a3 | 462 | |
61424318 | 463 | /* Set/clear disabled flag according to tp->flag */ |
c31ffb3f NK |
464 | if (trace_probe_is_enabled(&tk->tp)) |
465 | tk->rp.kp.flags &= ~KPROBE_FLAG_DISABLED; | |
61424318 | 466 | else |
c31ffb3f | 467 | tk->rp.kp.flags |= KPROBE_FLAG_DISABLED; |
61424318 | 468 | |
c31ffb3f NK |
469 | if (trace_kprobe_is_return(tk)) |
470 | ret = register_kretprobe(&tk->rp); | |
413d37d1 | 471 | else |
c31ffb3f | 472 | ret = register_kprobe(&tk->rp.kp); |
61424318 MH |
473 | |
474 | if (ret == 0) | |
c31ffb3f | 475 | tk->tp.flags |= TP_FLAG_REGISTERED; |
61424318 | 476 | else { |
a395d6a7 JP |
477 | pr_warn("Could not insert probe at %s+%lu: %d\n", |
478 | trace_kprobe_symbol(tk), trace_kprobe_offset(tk), ret); | |
c31ffb3f | 479 | if (ret == -ENOENT && trace_kprobe_is_on_module(tk)) { |
a395d6a7 | 480 | pr_warn("This probe might be able to register after target module is loaded. Continue.\n"); |
61424318 MH |
481 | ret = 0; |
482 | } else if (ret == -EILSEQ) { | |
a395d6a7 JP |
483 | pr_warn("Probing address(0x%p) is not an instruction boundary.\n", |
484 | tk->rp.kp.addr); | |
61424318 MH |
485 | ret = -EINVAL; |
486 | } | |
487 | } | |
488 | ||
489 | return ret; | |
490 | } | |
491 | ||
492 | /* Internal unregister function - just handle k*probes and flags */ | |
c31ffb3f | 493 | static void __unregister_trace_kprobe(struct trace_kprobe *tk) |
61424318 | 494 | { |
c31ffb3f NK |
495 | if (trace_probe_is_registered(&tk->tp)) { |
496 | if (trace_kprobe_is_return(tk)) | |
497 | unregister_kretprobe(&tk->rp); | |
61424318 | 498 | else |
c31ffb3f NK |
499 | unregister_kprobe(&tk->rp.kp); |
500 | tk->tp.flags &= ~TP_FLAG_REGISTERED; | |
61424318 | 501 | /* Cleanup kprobe for reuse */ |
c31ffb3f NK |
502 | if (tk->rp.kp.symbol_name) |
503 | tk->rp.kp.addr = NULL; | |
61424318 MH |
504 | } |
505 | } | |
506 | ||
507 | /* Unregister a trace_probe and probe_event: call with locking probe_lock */ | |
c31ffb3f | 508 | static int unregister_trace_kprobe(struct trace_kprobe *tk) |
61424318 | 509 | { |
02ca1521 | 510 | /* Enabled event can not be unregistered */ |
c31ffb3f | 511 | if (trace_probe_is_enabled(&tk->tp)) |
02ca1521 MH |
512 | return -EBUSY; |
513 | ||
40c32592 | 514 | /* Will fail if probe is being used by ftrace or perf */ |
c31ffb3f | 515 | if (unregister_kprobe_event(tk)) |
40c32592 SRRH |
516 | return -EBUSY; |
517 | ||
c31ffb3f NK |
518 | __unregister_trace_kprobe(tk); |
519 | list_del(&tk->list); | |
02ca1521 MH |
520 | |
521 | return 0; | |
413d37d1 MH |
522 | } |
523 | ||
524 | /* Register a trace_probe and probe_event */ | |
c31ffb3f | 525 | static int register_trace_kprobe(struct trace_kprobe *tk) |
413d37d1 | 526 | { |
c31ffb3f | 527 | struct trace_kprobe *old_tk; |
413d37d1 MH |
528 | int ret; |
529 | ||
530 | mutex_lock(&probe_lock); | |
531 | ||
61424318 | 532 | /* Delete old (same name) event if exist */ |
687fcc4a | 533 | old_tk = find_trace_kprobe(trace_event_name(&tk->tp.call), |
de7b2973 | 534 | tk->tp.call.class->system); |
c31ffb3f NK |
535 | if (old_tk) { |
536 | ret = unregister_trace_kprobe(old_tk); | |
02ca1521 MH |
537 | if (ret < 0) |
538 | goto end; | |
c31ffb3f | 539 | free_trace_kprobe(old_tk); |
2d5e067e | 540 | } |
61424318 MH |
541 | |
542 | /* Register new event */ | |
c31ffb3f | 543 | ret = register_kprobe_event(tk); |
2d5e067e | 544 | if (ret) { |
a395d6a7 | 545 | pr_warn("Failed to register probe event(%d)\n", ret); |
2d5e067e MH |
546 | goto end; |
547 | } | |
548 | ||
61424318 | 549 | /* Register k*probe */ |
c31ffb3f | 550 | ret = __register_trace_kprobe(tk); |
61424318 | 551 | if (ret < 0) |
c31ffb3f | 552 | unregister_kprobe_event(tk); |
61424318 | 553 | else |
c31ffb3f | 554 | list_add_tail(&tk->list, &probe_list); |
61424318 | 555 | |
413d37d1 MH |
556 | end: |
557 | mutex_unlock(&probe_lock); | |
558 | return ret; | |
559 | } | |
560 | ||
61424318 | 561 | /* Module notifier call back, checking event on the module */ |
c31ffb3f | 562 | static int trace_kprobe_module_callback(struct notifier_block *nb, |
61424318 MH |
563 | unsigned long val, void *data) |
564 | { | |
565 | struct module *mod = data; | |
c31ffb3f | 566 | struct trace_kprobe *tk; |
61424318 MH |
567 | int ret; |
568 | ||
569 | if (val != MODULE_STATE_COMING) | |
570 | return NOTIFY_DONE; | |
571 | ||
572 | /* Update probes on coming module */ | |
573 | mutex_lock(&probe_lock); | |
c31ffb3f NK |
574 | list_for_each_entry(tk, &probe_list, list) { |
575 | if (trace_kprobe_within_module(tk, mod)) { | |
02ca1521 | 576 | /* Don't need to check busy - this should have gone. */ |
c31ffb3f NK |
577 | __unregister_trace_kprobe(tk); |
578 | ret = __register_trace_kprobe(tk); | |
61424318 | 579 | if (ret) |
a395d6a7 JP |
580 | pr_warn("Failed to re-register probe %s on %s: %d\n", |
581 | trace_event_name(&tk->tp.call), | |
582 | mod->name, ret); | |
61424318 MH |
583 | } |
584 | } | |
585 | mutex_unlock(&probe_lock); | |
586 | ||
587 | return NOTIFY_DONE; | |
588 | } | |
589 | ||
c31ffb3f NK |
590 | static struct notifier_block trace_kprobe_module_nb = { |
591 | .notifier_call = trace_kprobe_module_callback, | |
61424318 MH |
592 | .priority = 1 /* Invoked after kprobe module callback */ |
593 | }; | |
594 | ||
c31ffb3f | 595 | static int create_trace_kprobe(int argc, char **argv) |
413d37d1 MH |
596 | { |
597 | /* | |
598 | * Argument syntax: | |
61424318 MH |
599 | * - Add kprobe: p[:[GRP/]EVENT] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS] |
600 | * - Add kretprobe: r[:[GRP/]EVENT] [MOD:]KSYM[+0] [FETCHARGS] | |
413d37d1 | 601 | * Fetch args: |
2e06ff63 MH |
602 | * $retval : fetch return value |
603 | * $stack : fetch stack address | |
604 | * $stackN : fetch Nth of stack (N:0-) | |
35abb67d | 605 | * $comm : fetch current task comm |
413d37d1 MH |
606 | * @ADDR : fetch memory at ADDR (ADDR should be in kernel) |
607 | * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol) | |
608 | * %REG : fetch register REG | |
93ccae7a | 609 | * Dereferencing memory fetch: |
413d37d1 | 610 | * +|-offs(ARG) : fetch memory at ARG +|- offs address. |
eca0d916 MH |
611 | * Alias name of args: |
612 | * NAME=FETCHARG : set NAME as alias of FETCHARG. | |
93ccae7a MH |
613 | * Type of args: |
614 | * FETCHARG:TYPE : use TYPE instead of unsigned long. | |
413d37d1 | 615 | */ |
c31ffb3f | 616 | struct trace_kprobe *tk; |
413d37d1 | 617 | int i, ret = 0; |
3a6b7666 | 618 | bool is_return = false, is_delete = false; |
93ccae7a | 619 | char *symbol = NULL, *event = NULL, *group = NULL; |
da34634f | 620 | char *arg; |
2fba0c88 | 621 | unsigned long offset = 0; |
413d37d1 | 622 | void *addr = NULL; |
4a846b44 | 623 | char buf[MAX_EVENT_NAME_LEN]; |
413d37d1 | 624 | |
a7c312be | 625 | /* argc must be >= 1 */ |
413d37d1 | 626 | if (argv[0][0] == 'p') |
3a6b7666 | 627 | is_return = false; |
413d37d1 | 628 | else if (argv[0][0] == 'r') |
3a6b7666 | 629 | is_return = true; |
a7c312be | 630 | else if (argv[0][0] == '-') |
3a6b7666 | 631 | is_delete = true; |
e63cc239 | 632 | else { |
a7c312be MH |
633 | pr_info("Probe definition must be started with 'p', 'r' or" |
634 | " '-'.\n"); | |
413d37d1 | 635 | return -EINVAL; |
e63cc239 | 636 | } |
413d37d1 MH |
637 | |
638 | if (argv[0][1] == ':') { | |
639 | event = &argv[0][2]; | |
f52487e9 MH |
640 | if (strchr(event, '/')) { |
641 | group = event; | |
642 | event = strchr(group, '/') + 1; | |
643 | event[-1] = '\0'; | |
644 | if (strlen(group) == 0) { | |
a5efd925 | 645 | pr_info("Group name is not specified\n"); |
f52487e9 MH |
646 | return -EINVAL; |
647 | } | |
648 | } | |
413d37d1 | 649 | if (strlen(event) == 0) { |
a5efd925 | 650 | pr_info("Event name is not specified\n"); |
413d37d1 MH |
651 | return -EINVAL; |
652 | } | |
653 | } | |
a7c312be MH |
654 | if (!group) |
655 | group = KPROBE_EVENT_SYSTEM; | |
413d37d1 | 656 | |
a7c312be MH |
657 | if (is_delete) { |
658 | if (!event) { | |
659 | pr_info("Delete command needs an event name.\n"); | |
660 | return -EINVAL; | |
661 | } | |
9da79ab8 | 662 | mutex_lock(&probe_lock); |
c31ffb3f NK |
663 | tk = find_trace_kprobe(event, group); |
664 | if (!tk) { | |
9da79ab8 | 665 | mutex_unlock(&probe_lock); |
a7c312be MH |
666 | pr_info("Event %s/%s doesn't exist.\n", group, event); |
667 | return -ENOENT; | |
668 | } | |
669 | /* delete an event */ | |
c31ffb3f | 670 | ret = unregister_trace_kprobe(tk); |
02ca1521 | 671 | if (ret == 0) |
c31ffb3f | 672 | free_trace_kprobe(tk); |
9da79ab8 | 673 | mutex_unlock(&probe_lock); |
02ca1521 | 674 | return ret; |
a7c312be MH |
675 | } |
676 | ||
677 | if (argc < 2) { | |
678 | pr_info("Probe point is not specified.\n"); | |
679 | return -EINVAL; | |
680 | } | |
413d37d1 | 681 | if (isdigit(argv[1][0])) { |
e63cc239 MH |
682 | if (is_return) { |
683 | pr_info("Return probe point must be a symbol.\n"); | |
413d37d1 | 684 | return -EINVAL; |
e63cc239 | 685 | } |
413d37d1 | 686 | /* an address specified */ |
bcd83ea6 | 687 | ret = kstrtoul(&argv[1][0], 0, (unsigned long *)&addr); |
e63cc239 MH |
688 | if (ret) { |
689 | pr_info("Failed to parse address.\n"); | |
413d37d1 | 690 | return ret; |
e63cc239 | 691 | } |
413d37d1 MH |
692 | } else { |
693 | /* a symbol specified */ | |
694 | symbol = argv[1]; | |
695 | /* TODO: support .init module functions */ | |
8ab83f56 | 696 | ret = traceprobe_split_symbol_offset(symbol, &offset); |
e63cc239 MH |
697 | if (ret) { |
698 | pr_info("Failed to parse symbol.\n"); | |
413d37d1 | 699 | return ret; |
e63cc239 MH |
700 | } |
701 | if (offset && is_return) { | |
702 | pr_info("Return probe must be used without offset.\n"); | |
413d37d1 | 703 | return -EINVAL; |
e63cc239 | 704 | } |
413d37d1 | 705 | } |
a82378d8 | 706 | argc -= 2; argv += 2; |
413d37d1 MH |
707 | |
708 | /* setup a probe */ | |
4263565d MH |
709 | if (!event) { |
710 | /* Make a new event name */ | |
4263565d | 711 | if (symbol) |
6f3cf440 | 712 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld", |
4263565d MH |
713 | is_return ? 'r' : 'p', symbol, offset); |
714 | else | |
6f3cf440 | 715 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p", |
4263565d | 716 | is_return ? 'r' : 'p', addr); |
4a846b44 MH |
717 | event = buf; |
718 | } | |
c31ffb3f | 719 | tk = alloc_trace_kprobe(group, event, addr, symbol, offset, argc, |
f52487e9 | 720 | is_return); |
c31ffb3f | 721 | if (IS_ERR(tk)) { |
e63cc239 | 722 | pr_info("Failed to allocate trace_probe.(%d)\n", |
c31ffb3f NK |
723 | (int)PTR_ERR(tk)); |
724 | return PTR_ERR(tk); | |
e63cc239 | 725 | } |
413d37d1 | 726 | |
413d37d1 | 727 | /* parse arguments */ |
a82378d8 MH |
728 | ret = 0; |
729 | for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { | |
c31ffb3f NK |
730 | struct probe_arg *parg = &tk->tp.args[i]; |
731 | ||
61a52736 | 732 | /* Increment count for freeing args in error case */ |
c31ffb3f | 733 | tk->tp.nr_args++; |
61a52736 | 734 | |
eca0d916 MH |
735 | /* Parse argument name */ |
736 | arg = strchr(argv[i], '='); | |
aba91595 | 737 | if (arg) { |
eca0d916 | 738 | *arg++ = '\0'; |
c31ffb3f | 739 | parg->name = kstrdup(argv[i], GFP_KERNEL); |
aba91595 | 740 | } else { |
eca0d916 | 741 | arg = argv[i]; |
aba91595 MH |
742 | /* If argument name is omitted, set "argN" */ |
743 | snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1); | |
c31ffb3f | 744 | parg->name = kstrdup(buf, GFP_KERNEL); |
aba91595 | 745 | } |
a703d946 | 746 | |
c31ffb3f | 747 | if (!parg->name) { |
aba91595 | 748 | pr_info("Failed to allocate argument[%d] name.\n", i); |
ba8665d7 | 749 | ret = -ENOMEM; |
413d37d1 MH |
750 | goto error; |
751 | } | |
da34634f | 752 | |
c31ffb3f | 753 | if (!is_good_name(parg->name)) { |
da34634f | 754 | pr_info("Invalid argument[%d] name: %s\n", |
c31ffb3f | 755 | i, parg->name); |
da34634f MH |
756 | ret = -EINVAL; |
757 | goto error; | |
758 | } | |
93ccae7a | 759 | |
c31ffb3f NK |
760 | if (traceprobe_conflict_field_name(parg->name, |
761 | tk->tp.args, i)) { | |
aba91595 | 762 | pr_info("Argument[%d] name '%s' conflicts with " |
93ccae7a MH |
763 | "another field.\n", i, argv[i]); |
764 | ret = -EINVAL; | |
765 | goto error; | |
766 | } | |
ba8665d7 MH |
767 | |
768 | /* Parse fetch argument */ | |
c31ffb3f | 769 | ret = traceprobe_parse_probe_arg(arg, &tk->tp.size, parg, |
d9a16d3a SR |
770 | is_return, true, |
771 | kprobes_fetch_type_table); | |
e63cc239 | 772 | if (ret) { |
aba91595 | 773 | pr_info("Parse error at argument[%d]. (%d)\n", i, ret); |
413d37d1 | 774 | goto error; |
e63cc239 | 775 | } |
413d37d1 | 776 | } |
413d37d1 | 777 | |
c31ffb3f | 778 | ret = register_trace_kprobe(tk); |
413d37d1 MH |
779 | if (ret) |
780 | goto error; | |
781 | return 0; | |
782 | ||
783 | error: | |
c31ffb3f | 784 | free_trace_kprobe(tk); |
413d37d1 MH |
785 | return ret; |
786 | } | |
787 | ||
c31ffb3f | 788 | static int release_all_trace_kprobes(void) |
413d37d1 | 789 | { |
c31ffb3f | 790 | struct trace_kprobe *tk; |
02ca1521 | 791 | int ret = 0; |
413d37d1 MH |
792 | |
793 | mutex_lock(&probe_lock); | |
02ca1521 | 794 | /* Ensure no probe is in use. */ |
c31ffb3f NK |
795 | list_for_each_entry(tk, &probe_list, list) |
796 | if (trace_probe_is_enabled(&tk->tp)) { | |
02ca1521 MH |
797 | ret = -EBUSY; |
798 | goto end; | |
799 | } | |
413d37d1 MH |
800 | /* TODO: Use batch unregistration */ |
801 | while (!list_empty(&probe_list)) { | |
c31ffb3f NK |
802 | tk = list_entry(probe_list.next, struct trace_kprobe, list); |
803 | ret = unregister_trace_kprobe(tk); | |
40c32592 SRRH |
804 | if (ret) |
805 | goto end; | |
c31ffb3f | 806 | free_trace_kprobe(tk); |
413d37d1 | 807 | } |
02ca1521 MH |
808 | |
809 | end: | |
413d37d1 | 810 | mutex_unlock(&probe_lock); |
02ca1521 MH |
811 | |
812 | return ret; | |
413d37d1 MH |
813 | } |
814 | ||
413d37d1 MH |
815 | /* Probes listing interfaces */ |
816 | static void *probes_seq_start(struct seq_file *m, loff_t *pos) | |
817 | { | |
818 | mutex_lock(&probe_lock); | |
819 | return seq_list_start(&probe_list, *pos); | |
820 | } | |
821 | ||
822 | static void *probes_seq_next(struct seq_file *m, void *v, loff_t *pos) | |
823 | { | |
824 | return seq_list_next(v, &probe_list, pos); | |
825 | } | |
826 | ||
827 | static void probes_seq_stop(struct seq_file *m, void *v) | |
828 | { | |
829 | mutex_unlock(&probe_lock); | |
830 | } | |
831 | ||
832 | static int probes_seq_show(struct seq_file *m, void *v) | |
833 | { | |
c31ffb3f | 834 | struct trace_kprobe *tk = v; |
93ccae7a | 835 | int i; |
413d37d1 | 836 | |
fa6f0cc7 | 837 | seq_putc(m, trace_kprobe_is_return(tk) ? 'r' : 'p'); |
de7b2973 | 838 | seq_printf(m, ":%s/%s", tk->tp.call.class->system, |
687fcc4a | 839 | trace_event_name(&tk->tp.call)); |
413d37d1 | 840 | |
c31ffb3f NK |
841 | if (!tk->symbol) |
842 | seq_printf(m, " 0x%p", tk->rp.kp.addr); | |
843 | else if (tk->rp.kp.offset) | |
844 | seq_printf(m, " %s+%u", trace_kprobe_symbol(tk), | |
845 | tk->rp.kp.offset); | |
413d37d1 | 846 | else |
c31ffb3f | 847 | seq_printf(m, " %s", trace_kprobe_symbol(tk)); |
413d37d1 | 848 | |
c31ffb3f NK |
849 | for (i = 0; i < tk->tp.nr_args; i++) |
850 | seq_printf(m, " %s=%s", tk->tp.args[i].name, tk->tp.args[i].comm); | |
fa6f0cc7 | 851 | seq_putc(m, '\n'); |
93ccae7a | 852 | |
413d37d1 MH |
853 | return 0; |
854 | } | |
855 | ||
856 | static const struct seq_operations probes_seq_op = { | |
857 | .start = probes_seq_start, | |
858 | .next = probes_seq_next, | |
859 | .stop = probes_seq_stop, | |
860 | .show = probes_seq_show | |
861 | }; | |
862 | ||
863 | static int probes_open(struct inode *inode, struct file *file) | |
864 | { | |
02ca1521 MH |
865 | int ret; |
866 | ||
867 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { | |
c31ffb3f | 868 | ret = release_all_trace_kprobes(); |
02ca1521 MH |
869 | if (ret < 0) |
870 | return ret; | |
871 | } | |
413d37d1 MH |
872 | |
873 | return seq_open(file, &probes_seq_op); | |
874 | } | |
875 | ||
413d37d1 MH |
876 | static ssize_t probes_write(struct file *file, const char __user *buffer, |
877 | size_t count, loff_t *ppos) | |
878 | { | |
8ab83f56 | 879 | return traceprobe_probes_write(file, buffer, count, ppos, |
c31ffb3f | 880 | create_trace_kprobe); |
413d37d1 MH |
881 | } |
882 | ||
883 | static const struct file_operations kprobe_events_ops = { | |
884 | .owner = THIS_MODULE, | |
885 | .open = probes_open, | |
886 | .read = seq_read, | |
887 | .llseek = seq_lseek, | |
888 | .release = seq_release, | |
889 | .write = probes_write, | |
890 | }; | |
891 | ||
cd7e7bd5 MH |
892 | /* Probes profiling interfaces */ |
893 | static int probes_profile_seq_show(struct seq_file *m, void *v) | |
894 | { | |
c31ffb3f | 895 | struct trace_kprobe *tk = v; |
cd7e7bd5 | 896 | |
de7b2973 | 897 | seq_printf(m, " %-44s %15lu %15lu\n", |
f18f97ac MN |
898 | trace_event_name(&tk->tp.call), |
899 | trace_kprobe_nhit(tk), | |
c31ffb3f | 900 | tk->rp.kp.nmissed); |
cd7e7bd5 MH |
901 | |
902 | return 0; | |
903 | } | |
904 | ||
905 | static const struct seq_operations profile_seq_op = { | |
906 | .start = probes_seq_start, | |
907 | .next = probes_seq_next, | |
908 | .stop = probes_seq_stop, | |
909 | .show = probes_profile_seq_show | |
910 | }; | |
911 | ||
912 | static int profile_open(struct inode *inode, struct file *file) | |
913 | { | |
914 | return seq_open(file, &profile_seq_op); | |
915 | } | |
916 | ||
917 | static const struct file_operations kprobe_profile_ops = { | |
918 | .owner = THIS_MODULE, | |
919 | .open = profile_open, | |
920 | .read = seq_read, | |
921 | .llseek = seq_lseek, | |
922 | .release = seq_release, | |
923 | }; | |
924 | ||
413d37d1 | 925 | /* Kprobe handler */ |
3da0f180 | 926 | static nokprobe_inline void |
c31ffb3f | 927 | __kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs, |
7f1d2f82 | 928 | struct trace_event_file *trace_file) |
413d37d1 | 929 | { |
93ccae7a | 930 | struct kprobe_trace_entry_head *entry; |
413d37d1 | 931 | struct ring_buffer_event *event; |
8f8ffe24 | 932 | struct ring_buffer *buffer; |
e09c8614 | 933 | int size, dsize, pc; |
413d37d1 | 934 | unsigned long irq_flags; |
2425bcb9 | 935 | struct trace_event_call *call = &tk->tp.call; |
413d37d1 | 936 | |
7f1d2f82 | 937 | WARN_ON(call != trace_file->event_call); |
41a7dd42 | 938 | |
09a5059a | 939 | if (trace_trigger_soft_disabled(trace_file)) |
13a1e4ae | 940 | return; |
b8820084 | 941 | |
413d37d1 MH |
942 | local_save_flags(irq_flags); |
943 | pc = preempt_count(); | |
944 | ||
c31ffb3f NK |
945 | dsize = __get_data_size(&tk->tp, regs); |
946 | size = sizeof(*entry) + tk->tp.size + dsize; | |
413d37d1 | 947 | |
7f1d2f82 | 948 | event = trace_event_buffer_lock_reserve(&buffer, trace_file, |
41a7dd42 MH |
949 | call->event.type, |
950 | size, irq_flags, pc); | |
413d37d1 | 951 | if (!event) |
1e12a4a7 | 952 | return; |
413d37d1 MH |
953 | |
954 | entry = ring_buffer_event_data(event); | |
c31ffb3f NK |
955 | entry->ip = (unsigned long)tk->rp.kp.addr; |
956 | store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); | |
413d37d1 | 957 | |
7f1d2f82 | 958 | event_trigger_unlock_commit_regs(trace_file, buffer, event, |
13a1e4ae | 959 | entry, irq_flags, pc, regs); |
413d37d1 MH |
960 | } |
961 | ||
3da0f180 | 962 | static void |
c31ffb3f | 963 | kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs) |
41a7dd42 | 964 | { |
b04d52e3 | 965 | struct event_file_link *link; |
41a7dd42 | 966 | |
c31ffb3f NK |
967 | list_for_each_entry_rcu(link, &tk->tp.files, list) |
968 | __kprobe_trace_func(tk, regs, link->file); | |
41a7dd42 | 969 | } |
3da0f180 | 970 | NOKPROBE_SYMBOL(kprobe_trace_func); |
41a7dd42 | 971 | |
413d37d1 | 972 | /* Kretprobe handler */ |
3da0f180 | 973 | static nokprobe_inline void |
c31ffb3f | 974 | __kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, |
41a7dd42 | 975 | struct pt_regs *regs, |
7f1d2f82 | 976 | struct trace_event_file *trace_file) |
413d37d1 | 977 | { |
93ccae7a | 978 | struct kretprobe_trace_entry_head *entry; |
413d37d1 | 979 | struct ring_buffer_event *event; |
8f8ffe24 | 980 | struct ring_buffer *buffer; |
e09c8614 | 981 | int size, pc, dsize; |
413d37d1 | 982 | unsigned long irq_flags; |
2425bcb9 | 983 | struct trace_event_call *call = &tk->tp.call; |
413d37d1 | 984 | |
7f1d2f82 | 985 | WARN_ON(call != trace_file->event_call); |
41a7dd42 | 986 | |
09a5059a | 987 | if (trace_trigger_soft_disabled(trace_file)) |
13a1e4ae | 988 | return; |
b8820084 | 989 | |
413d37d1 MH |
990 | local_save_flags(irq_flags); |
991 | pc = preempt_count(); | |
992 | ||
c31ffb3f NK |
993 | dsize = __get_data_size(&tk->tp, regs); |
994 | size = sizeof(*entry) + tk->tp.size + dsize; | |
413d37d1 | 995 | |
7f1d2f82 | 996 | event = trace_event_buffer_lock_reserve(&buffer, trace_file, |
41a7dd42 MH |
997 | call->event.type, |
998 | size, irq_flags, pc); | |
413d37d1 | 999 | if (!event) |
1e12a4a7 | 1000 | return; |
413d37d1 MH |
1001 | |
1002 | entry = ring_buffer_event_data(event); | |
c31ffb3f | 1003 | entry->func = (unsigned long)tk->rp.kp.addr; |
413d37d1 | 1004 | entry->ret_ip = (unsigned long)ri->ret_addr; |
c31ffb3f | 1005 | store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); |
413d37d1 | 1006 | |
7f1d2f82 | 1007 | event_trigger_unlock_commit_regs(trace_file, buffer, event, |
13a1e4ae | 1008 | entry, irq_flags, pc, regs); |
413d37d1 MH |
1009 | } |
1010 | ||
3da0f180 | 1011 | static void |
c31ffb3f | 1012 | kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, |
41a7dd42 MH |
1013 | struct pt_regs *regs) |
1014 | { | |
b04d52e3 | 1015 | struct event_file_link *link; |
41a7dd42 | 1016 | |
c31ffb3f NK |
1017 | list_for_each_entry_rcu(link, &tk->tp.files, list) |
1018 | __kretprobe_trace_func(tk, ri, regs, link->file); | |
41a7dd42 | 1019 | } |
3da0f180 | 1020 | NOKPROBE_SYMBOL(kretprobe_trace_func); |
41a7dd42 | 1021 | |
413d37d1 | 1022 | /* Event entry printers */ |
b62fdd97 | 1023 | static enum print_line_t |
a9a57763 SR |
1024 | print_kprobe_event(struct trace_iterator *iter, int flags, |
1025 | struct trace_event *event) | |
413d37d1 | 1026 | { |
93ccae7a | 1027 | struct kprobe_trace_entry_head *field; |
413d37d1 | 1028 | struct trace_seq *s = &iter->seq; |
eca0d916 | 1029 | struct trace_probe *tp; |
93ccae7a | 1030 | u8 *data; |
413d37d1 MH |
1031 | int i; |
1032 | ||
93ccae7a | 1033 | field = (struct kprobe_trace_entry_head *)iter->ent; |
80decc70 | 1034 | tp = container_of(event, struct trace_probe, call.event); |
413d37d1 | 1035 | |
687fcc4a | 1036 | trace_seq_printf(s, "%s: (", trace_event_name(&tp->call)); |
6e9f23d1 | 1037 | |
413d37d1 | 1038 | if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET)) |
85224da0 | 1039 | goto out; |
413d37d1 | 1040 | |
85224da0 | 1041 | trace_seq_putc(s, ')'); |
413d37d1 | 1042 | |
93ccae7a MH |
1043 | data = (u8 *)&field[1]; |
1044 | for (i = 0; i < tp->nr_args; i++) | |
1045 | if (!tp->args[i].type->print(s, tp->args[i].name, | |
e09c8614 | 1046 | data + tp->args[i].offset, field)) |
85224da0 | 1047 | goto out; |
413d37d1 | 1048 | |
85224da0 SRRH |
1049 | trace_seq_putc(s, '\n'); |
1050 | out: | |
1051 | return trace_handle_return(s); | |
413d37d1 MH |
1052 | } |
1053 | ||
b62fdd97 | 1054 | static enum print_line_t |
a9a57763 SR |
1055 | print_kretprobe_event(struct trace_iterator *iter, int flags, |
1056 | struct trace_event *event) | |
413d37d1 | 1057 | { |
93ccae7a | 1058 | struct kretprobe_trace_entry_head *field; |
413d37d1 | 1059 | struct trace_seq *s = &iter->seq; |
eca0d916 | 1060 | struct trace_probe *tp; |
93ccae7a | 1061 | u8 *data; |
413d37d1 MH |
1062 | int i; |
1063 | ||
93ccae7a | 1064 | field = (struct kretprobe_trace_entry_head *)iter->ent; |
80decc70 | 1065 | tp = container_of(event, struct trace_probe, call.event); |
413d37d1 | 1066 | |
687fcc4a | 1067 | trace_seq_printf(s, "%s: (", trace_event_name(&tp->call)); |
6e9f23d1 | 1068 | |
413d37d1 | 1069 | if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET)) |
85224da0 | 1070 | goto out; |
413d37d1 | 1071 | |
85224da0 | 1072 | trace_seq_puts(s, " <- "); |
413d37d1 MH |
1073 | |
1074 | if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET)) | |
85224da0 | 1075 | goto out; |
413d37d1 | 1076 | |
85224da0 | 1077 | trace_seq_putc(s, ')'); |
413d37d1 | 1078 | |
93ccae7a MH |
1079 | data = (u8 *)&field[1]; |
1080 | for (i = 0; i < tp->nr_args; i++) | |
1081 | if (!tp->args[i].type->print(s, tp->args[i].name, | |
e09c8614 | 1082 | data + tp->args[i].offset, field)) |
85224da0 | 1083 | goto out; |
413d37d1 | 1084 | |
85224da0 | 1085 | trace_seq_putc(s, '\n'); |
413d37d1 | 1086 | |
85224da0 SRRH |
1087 | out: |
1088 | return trace_handle_return(s); | |
413d37d1 MH |
1089 | } |
1090 | ||
413d37d1 | 1091 | |
2425bcb9 | 1092 | static int kprobe_event_define_fields(struct trace_event_call *event_call) |
413d37d1 MH |
1093 | { |
1094 | int ret, i; | |
93ccae7a | 1095 | struct kprobe_trace_entry_head field; |
c31ffb3f | 1096 | struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data; |
413d37d1 | 1097 | |
a703d946 | 1098 | DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0); |
eca0d916 | 1099 | /* Set argument names as fields */ |
c31ffb3f NK |
1100 | for (i = 0; i < tk->tp.nr_args; i++) { |
1101 | struct probe_arg *parg = &tk->tp.args[i]; | |
1102 | ||
1103 | ret = trace_define_field(event_call, parg->type->fmttype, | |
1104 | parg->name, | |
1105 | sizeof(field) + parg->offset, | |
1106 | parg->type->size, | |
1107 | parg->type->is_signed, | |
93ccae7a MH |
1108 | FILTER_OTHER); |
1109 | if (ret) | |
1110 | return ret; | |
1111 | } | |
413d37d1 MH |
1112 | return 0; |
1113 | } | |
1114 | ||
2425bcb9 | 1115 | static int kretprobe_event_define_fields(struct trace_event_call *event_call) |
413d37d1 MH |
1116 | { |
1117 | int ret, i; | |
93ccae7a | 1118 | struct kretprobe_trace_entry_head field; |
c31ffb3f | 1119 | struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data; |
413d37d1 | 1120 | |
a703d946 MH |
1121 | DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0); |
1122 | DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0); | |
eca0d916 | 1123 | /* Set argument names as fields */ |
c31ffb3f NK |
1124 | for (i = 0; i < tk->tp.nr_args; i++) { |
1125 | struct probe_arg *parg = &tk->tp.args[i]; | |
1126 | ||
1127 | ret = trace_define_field(event_call, parg->type->fmttype, | |
1128 | parg->name, | |
1129 | sizeof(field) + parg->offset, | |
1130 | parg->type->size, | |
1131 | parg->type->is_signed, | |
93ccae7a MH |
1132 | FILTER_OTHER); |
1133 | if (ret) | |
1134 | return ret; | |
1135 | } | |
413d37d1 MH |
1136 | return 0; |
1137 | } | |
1138 | ||
07b139c8 | 1139 | #ifdef CONFIG_PERF_EVENTS |
e08d1c65 MH |
1140 | |
1141 | /* Kprobe profile handler */ | |
3da0f180 | 1142 | static void |
c31ffb3f | 1143 | kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs) |
e08d1c65 | 1144 | { |
2425bcb9 | 1145 | struct trace_event_call *call = &tk->tp.call; |
2541517c | 1146 | struct bpf_prog *prog = call->prog; |
93ccae7a | 1147 | struct kprobe_trace_entry_head *entry; |
1c024eca | 1148 | struct hlist_head *head; |
e09c8614 | 1149 | int size, __size, dsize; |
4ed7c92d | 1150 | int rctx; |
e08d1c65 | 1151 | |
2541517c AS |
1152 | if (prog && !trace_call_bpf(prog, regs)) |
1153 | return; | |
1154 | ||
288e984e ON |
1155 | head = this_cpu_ptr(call->perf_events); |
1156 | if (hlist_empty(head)) | |
1157 | return; | |
1158 | ||
c31ffb3f NK |
1159 | dsize = __get_data_size(&tk->tp, regs); |
1160 | __size = sizeof(*entry) + tk->tp.size + dsize; | |
74ebb63e MH |
1161 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
1162 | size -= sizeof(u32); | |
ce71b9df | 1163 | |
1e1dcd93 | 1164 | entry = perf_trace_buf_alloc(size, NULL, &rctx); |
430ad5a6 | 1165 | if (!entry) |
1e12a4a7 | 1166 | return; |
a1a138d0 | 1167 | |
c31ffb3f | 1168 | entry->ip = (unsigned long)tk->rp.kp.addr; |
e09c8614 | 1169 | memset(&entry[1], 0, dsize); |
c31ffb3f | 1170 | store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); |
1e1dcd93 AS |
1171 | perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, |
1172 | head, NULL); | |
e08d1c65 | 1173 | } |
3da0f180 | 1174 | NOKPROBE_SYMBOL(kprobe_perf_func); |
e08d1c65 MH |
1175 | |
1176 | /* Kretprobe profile handler */ | |
3da0f180 | 1177 | static void |
c31ffb3f | 1178 | kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, |
2b106aab | 1179 | struct pt_regs *regs) |
e08d1c65 | 1180 | { |
2425bcb9 | 1181 | struct trace_event_call *call = &tk->tp.call; |
2541517c | 1182 | struct bpf_prog *prog = call->prog; |
93ccae7a | 1183 | struct kretprobe_trace_entry_head *entry; |
1c024eca | 1184 | struct hlist_head *head; |
e09c8614 | 1185 | int size, __size, dsize; |
4ed7c92d | 1186 | int rctx; |
e08d1c65 | 1187 | |
2541517c AS |
1188 | if (prog && !trace_call_bpf(prog, regs)) |
1189 | return; | |
1190 | ||
288e984e ON |
1191 | head = this_cpu_ptr(call->perf_events); |
1192 | if (hlist_empty(head)) | |
1193 | return; | |
1194 | ||
c31ffb3f NK |
1195 | dsize = __get_data_size(&tk->tp, regs); |
1196 | __size = sizeof(*entry) + tk->tp.size + dsize; | |
74ebb63e MH |
1197 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
1198 | size -= sizeof(u32); | |
444a2a3b | 1199 | |
1e1dcd93 | 1200 | entry = perf_trace_buf_alloc(size, NULL, &rctx); |
430ad5a6 | 1201 | if (!entry) |
1e12a4a7 | 1202 | return; |
e08d1c65 | 1203 | |
c31ffb3f | 1204 | entry->func = (unsigned long)tk->rp.kp.addr; |
a1a138d0 | 1205 | entry->ret_ip = (unsigned long)ri->ret_addr; |
c31ffb3f | 1206 | store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); |
1e1dcd93 AS |
1207 | perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, |
1208 | head, NULL); | |
e08d1c65 | 1209 | } |
3da0f180 | 1210 | NOKPROBE_SYMBOL(kretprobe_perf_func); |
07b139c8 | 1211 | #endif /* CONFIG_PERF_EVENTS */ |
50d78056 | 1212 | |
3fe3d619 ON |
1213 | /* |
1214 | * called by perf_trace_init() or __ftrace_set_clr_event() under event_mutex. | |
1215 | * | |
1216 | * kprobe_trace_self_tests_init() does enable_trace_probe/disable_trace_probe | |
1217 | * lockless, but we can't race with this __init function. | |
1218 | */ | |
2425bcb9 | 1219 | static int kprobe_register(struct trace_event_call *event, |
fbc1963d | 1220 | enum trace_reg type, void *data) |
2239291a | 1221 | { |
c31ffb3f | 1222 | struct trace_kprobe *tk = (struct trace_kprobe *)event->data; |
7f1d2f82 | 1223 | struct trace_event_file *file = data; |
1538f888 | 1224 | |
2239291a SR |
1225 | switch (type) { |
1226 | case TRACE_REG_REGISTER: | |
c31ffb3f | 1227 | return enable_trace_kprobe(tk, file); |
2239291a | 1228 | case TRACE_REG_UNREGISTER: |
c31ffb3f | 1229 | return disable_trace_kprobe(tk, file); |
2239291a SR |
1230 | |
1231 | #ifdef CONFIG_PERF_EVENTS | |
1232 | case TRACE_REG_PERF_REGISTER: | |
c31ffb3f | 1233 | return enable_trace_kprobe(tk, NULL); |
2239291a | 1234 | case TRACE_REG_PERF_UNREGISTER: |
c31ffb3f | 1235 | return disable_trace_kprobe(tk, NULL); |
ceec0b6f JO |
1236 | case TRACE_REG_PERF_OPEN: |
1237 | case TRACE_REG_PERF_CLOSE: | |
489c75c3 JO |
1238 | case TRACE_REG_PERF_ADD: |
1239 | case TRACE_REG_PERF_DEL: | |
ceec0b6f | 1240 | return 0; |
2239291a SR |
1241 | #endif |
1242 | } | |
1243 | return 0; | |
1244 | } | |
50d78056 | 1245 | |
3da0f180 | 1246 | static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) |
50d78056 | 1247 | { |
c31ffb3f | 1248 | struct trace_kprobe *tk = container_of(kp, struct trace_kprobe, rp.kp); |
e08d1c65 | 1249 | |
a7636d9e | 1250 | raw_cpu_inc(*tk->nhit); |
48182bd2 | 1251 | |
c31ffb3f NK |
1252 | if (tk->tp.flags & TP_FLAG_TRACE) |
1253 | kprobe_trace_func(tk, regs); | |
07b139c8 | 1254 | #ifdef CONFIG_PERF_EVENTS |
c31ffb3f NK |
1255 | if (tk->tp.flags & TP_FLAG_PROFILE) |
1256 | kprobe_perf_func(tk, regs); | |
07b139c8 | 1257 | #endif |
50d78056 MH |
1258 | return 0; /* We don't tweek kernel, so just return 0 */ |
1259 | } | |
3da0f180 | 1260 | NOKPROBE_SYMBOL(kprobe_dispatcher); |
50d78056 | 1261 | |
3da0f180 MH |
1262 | static int |
1263 | kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs) | |
50d78056 | 1264 | { |
c31ffb3f | 1265 | struct trace_kprobe *tk = container_of(ri->rp, struct trace_kprobe, rp); |
50d78056 | 1266 | |
a7636d9e | 1267 | raw_cpu_inc(*tk->nhit); |
48182bd2 | 1268 | |
c31ffb3f NK |
1269 | if (tk->tp.flags & TP_FLAG_TRACE) |
1270 | kretprobe_trace_func(tk, ri, regs); | |
07b139c8 | 1271 | #ifdef CONFIG_PERF_EVENTS |
c31ffb3f NK |
1272 | if (tk->tp.flags & TP_FLAG_PROFILE) |
1273 | kretprobe_perf_func(tk, ri, regs); | |
07b139c8 | 1274 | #endif |
50d78056 MH |
1275 | return 0; /* We don't tweek kernel, so just return 0 */ |
1276 | } | |
3da0f180 | 1277 | NOKPROBE_SYMBOL(kretprobe_dispatcher); |
e08d1c65 | 1278 | |
a9a57763 SR |
1279 | static struct trace_event_functions kretprobe_funcs = { |
1280 | .trace = print_kretprobe_event | |
1281 | }; | |
1282 | ||
1283 | static struct trace_event_functions kprobe_funcs = { | |
1284 | .trace = print_kprobe_event | |
1285 | }; | |
1286 | ||
c31ffb3f | 1287 | static int register_kprobe_event(struct trace_kprobe *tk) |
413d37d1 | 1288 | { |
2425bcb9 | 1289 | struct trace_event_call *call = &tk->tp.call; |
413d37d1 MH |
1290 | int ret; |
1291 | ||
2425bcb9 | 1292 | /* Initialize trace_event_call */ |
ffb9f995 | 1293 | INIT_LIST_HEAD(&call->class->fields); |
c31ffb3f | 1294 | if (trace_kprobe_is_return(tk)) { |
80decc70 | 1295 | call->event.funcs = &kretprobe_funcs; |
2e33af02 | 1296 | call->class->define_fields = kretprobe_event_define_fields; |
413d37d1 | 1297 | } else { |
80decc70 | 1298 | call->event.funcs = &kprobe_funcs; |
2e33af02 | 1299 | call->class->define_fields = kprobe_event_define_fields; |
413d37d1 | 1300 | } |
5bf652aa | 1301 | if (set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0) |
a342a028 | 1302 | return -ENOMEM; |
9023c930 | 1303 | ret = register_trace_event(&call->event); |
32c0edae | 1304 | if (!ret) { |
a342a028 | 1305 | kfree(call->print_fmt); |
ff50d991 | 1306 | return -ENODEV; |
a342a028 | 1307 | } |
72cbbc89 | 1308 | call->flags = TRACE_EVENT_FL_KPROBE; |
2239291a | 1309 | call->class->reg = kprobe_register; |
c31ffb3f | 1310 | call->data = tk; |
413d37d1 | 1311 | ret = trace_add_event_call(call); |
ff50d991 | 1312 | if (ret) { |
de7b2973 | 1313 | pr_info("Failed to register kprobe event: %s\n", |
687fcc4a | 1314 | trace_event_name(call)); |
a342a028 | 1315 | kfree(call->print_fmt); |
9023c930 | 1316 | unregister_trace_event(&call->event); |
ff50d991 | 1317 | } |
413d37d1 MH |
1318 | return ret; |
1319 | } | |
1320 | ||
c31ffb3f | 1321 | static int unregister_kprobe_event(struct trace_kprobe *tk) |
413d37d1 | 1322 | { |
40c32592 SRRH |
1323 | int ret; |
1324 | ||
ff50d991 | 1325 | /* tp->event is unregistered in trace_remove_event_call() */ |
c31ffb3f | 1326 | ret = trace_remove_event_call(&tk->tp.call); |
40c32592 | 1327 | if (!ret) |
c31ffb3f | 1328 | kfree(tk->tp.call.print_fmt); |
40c32592 | 1329 | return ret; |
413d37d1 MH |
1330 | } |
1331 | ||
8434dc93 | 1332 | /* Make a tracefs interface for controlling probe points */ |
413d37d1 MH |
1333 | static __init int init_kprobe_trace(void) |
1334 | { | |
1335 | struct dentry *d_tracer; | |
1336 | struct dentry *entry; | |
413d37d1 | 1337 | |
c31ffb3f | 1338 | if (register_module_notifier(&trace_kprobe_module_nb)) |
61424318 MH |
1339 | return -EINVAL; |
1340 | ||
413d37d1 | 1341 | d_tracer = tracing_init_dentry(); |
14a5ae40 | 1342 | if (IS_ERR(d_tracer)) |
413d37d1 MH |
1343 | return 0; |
1344 | ||
8434dc93 | 1345 | entry = tracefs_create_file("kprobe_events", 0644, d_tracer, |
413d37d1 MH |
1346 | NULL, &kprobe_events_ops); |
1347 | ||
cd7e7bd5 | 1348 | /* Event list interface */ |
413d37d1 | 1349 | if (!entry) |
a395d6a7 | 1350 | pr_warn("Could not create tracefs 'kprobe_events' entry\n"); |
cd7e7bd5 MH |
1351 | |
1352 | /* Profile interface */ | |
8434dc93 | 1353 | entry = tracefs_create_file("kprobe_profile", 0444, d_tracer, |
cd7e7bd5 MH |
1354 | NULL, &kprobe_profile_ops); |
1355 | ||
1356 | if (!entry) | |
a395d6a7 | 1357 | pr_warn("Could not create tracefs 'kprobe_profile' entry\n"); |
413d37d1 MH |
1358 | return 0; |
1359 | } | |
1360 | fs_initcall(init_kprobe_trace); | |
1361 | ||
1362 | ||
1363 | #ifdef CONFIG_FTRACE_STARTUP_TEST | |
265a5b7e SR |
1364 | /* |
1365 | * The "__used" keeps gcc from removing the function symbol | |
d4d7ccc8 MN |
1366 | * from the kallsyms table. 'noinline' makes sure that there |
1367 | * isn't an inlined version used by the test method below | |
265a5b7e | 1368 | */ |
d4d7ccc8 MN |
1369 | static __used __init noinline int |
1370 | kprobe_trace_selftest_target(int a1, int a2, int a3, int a4, int a5, int a6) | |
413d37d1 MH |
1371 | { |
1372 | return a1 + a2 + a3 + a4 + a5 + a6; | |
1373 | } | |
1374 | ||
d4d7ccc8 | 1375 | static struct __init trace_event_file * |
c31ffb3f | 1376 | find_trace_probe_file(struct trace_kprobe *tk, struct trace_array *tr) |
41a7dd42 | 1377 | { |
7f1d2f82 | 1378 | struct trace_event_file *file; |
41a7dd42 MH |
1379 | |
1380 | list_for_each_entry(file, &tr->events, list) | |
c31ffb3f | 1381 | if (file->event_call == &tk->tp.call) |
41a7dd42 MH |
1382 | return file; |
1383 | ||
1384 | return NULL; | |
1385 | } | |
1386 | ||
3fe3d619 | 1387 | /* |
c31ffb3f | 1388 | * Nobody but us can call enable_trace_kprobe/disable_trace_kprobe at this |
3fe3d619 ON |
1389 | * stage, we can do this lockless. |
1390 | */ | |
413d37d1 MH |
1391 | static __init int kprobe_trace_self_tests_init(void) |
1392 | { | |
231e36f4 | 1393 | int ret, warn = 0; |
413d37d1 | 1394 | int (*target)(int, int, int, int, int, int); |
c31ffb3f | 1395 | struct trace_kprobe *tk; |
7f1d2f82 | 1396 | struct trace_event_file *file; |
413d37d1 | 1397 | |
748ec3a2 YY |
1398 | if (tracing_is_disabled()) |
1399 | return -ENODEV; | |
1400 | ||
413d37d1 MH |
1401 | target = kprobe_trace_selftest_target; |
1402 | ||
1403 | pr_info("Testing kprobe tracing: "); | |
1404 | ||
8ab83f56 SD |
1405 | ret = traceprobe_command("p:testprobe kprobe_trace_selftest_target " |
1406 | "$stack $stack0 +0($stack)", | |
c31ffb3f | 1407 | create_trace_kprobe); |
231e36f4 | 1408 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 1409 | pr_warn("error on probing function entry.\n"); |
231e36f4 MH |
1410 | warn++; |
1411 | } else { | |
1412 | /* Enable trace point */ | |
c31ffb3f NK |
1413 | tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); |
1414 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 1415 | pr_warn("error on getting new probe.\n"); |
231e36f4 | 1416 | warn++; |
41a7dd42 | 1417 | } else { |
c31ffb3f | 1418 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
1419 | if (WARN_ON_ONCE(file == NULL)) { |
1420 | pr_warn("error on getting probe file.\n"); | |
1421 | warn++; | |
1422 | } else | |
c31ffb3f | 1423 | enable_trace_kprobe(tk, file); |
41a7dd42 | 1424 | } |
231e36f4 | 1425 | } |
413d37d1 | 1426 | |
8ab83f56 | 1427 | ret = traceprobe_command("r:testprobe2 kprobe_trace_selftest_target " |
c31ffb3f | 1428 | "$retval", create_trace_kprobe); |
231e36f4 | 1429 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 1430 | pr_warn("error on probing function return.\n"); |
231e36f4 MH |
1431 | warn++; |
1432 | } else { | |
1433 | /* Enable trace point */ | |
c31ffb3f NK |
1434 | tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); |
1435 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 1436 | pr_warn("error on getting 2nd new probe.\n"); |
231e36f4 | 1437 | warn++; |
41a7dd42 | 1438 | } else { |
c31ffb3f | 1439 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
1440 | if (WARN_ON_ONCE(file == NULL)) { |
1441 | pr_warn("error on getting probe file.\n"); | |
1442 | warn++; | |
1443 | } else | |
c31ffb3f | 1444 | enable_trace_kprobe(tk, file); |
41a7dd42 | 1445 | } |
231e36f4 MH |
1446 | } |
1447 | ||
1448 | if (warn) | |
1449 | goto end; | |
413d37d1 MH |
1450 | |
1451 | ret = target(1, 2, 3, 4, 5, 6); | |
1452 | ||
d4d7ccc8 MN |
1453 | /* |
1454 | * Not expecting an error here, the check is only to prevent the | |
1455 | * optimizer from removing the call to target() as otherwise there | |
1456 | * are no side-effects and the call is never performed. | |
1457 | */ | |
1458 | if (ret != 21) | |
1459 | warn++; | |
1460 | ||
02ca1521 | 1461 | /* Disable trace points before removing it */ |
c31ffb3f NK |
1462 | tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); |
1463 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 1464 | pr_warn("error on getting test probe.\n"); |
02ca1521 | 1465 | warn++; |
41a7dd42 | 1466 | } else { |
d4d7ccc8 MN |
1467 | if (trace_kprobe_nhit(tk) != 1) { |
1468 | pr_warn("incorrect number of testprobe hits\n"); | |
1469 | warn++; | |
1470 | } | |
1471 | ||
c31ffb3f | 1472 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
1473 | if (WARN_ON_ONCE(file == NULL)) { |
1474 | pr_warn("error on getting probe file.\n"); | |
1475 | warn++; | |
1476 | } else | |
c31ffb3f | 1477 | disable_trace_kprobe(tk, file); |
41a7dd42 | 1478 | } |
02ca1521 | 1479 | |
c31ffb3f NK |
1480 | tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); |
1481 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 1482 | pr_warn("error on getting 2nd test probe.\n"); |
02ca1521 | 1483 | warn++; |
41a7dd42 | 1484 | } else { |
d4d7ccc8 MN |
1485 | if (trace_kprobe_nhit(tk) != 1) { |
1486 | pr_warn("incorrect number of testprobe2 hits\n"); | |
1487 | warn++; | |
1488 | } | |
1489 | ||
c31ffb3f | 1490 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
1491 | if (WARN_ON_ONCE(file == NULL)) { |
1492 | pr_warn("error on getting probe file.\n"); | |
1493 | warn++; | |
1494 | } else | |
c31ffb3f | 1495 | disable_trace_kprobe(tk, file); |
41a7dd42 | 1496 | } |
02ca1521 | 1497 | |
c31ffb3f | 1498 | ret = traceprobe_command("-:testprobe", create_trace_kprobe); |
231e36f4 | 1499 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 1500 | pr_warn("error on deleting a probe.\n"); |
231e36f4 MH |
1501 | warn++; |
1502 | } | |
1503 | ||
c31ffb3f | 1504 | ret = traceprobe_command("-:testprobe2", create_trace_kprobe); |
231e36f4 | 1505 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 1506 | pr_warn("error on deleting a probe.\n"); |
231e36f4 MH |
1507 | warn++; |
1508 | } | |
413d37d1 | 1509 | |
231e36f4 | 1510 | end: |
c31ffb3f | 1511 | release_all_trace_kprobes(); |
231e36f4 MH |
1512 | if (warn) |
1513 | pr_cont("NG: Some tests are failed. Please check them.\n"); | |
1514 | else | |
1515 | pr_cont("OK\n"); | |
413d37d1 MH |
1516 | return 0; |
1517 | } | |
1518 | ||
1519 | late_initcall(kprobe_trace_self_tests_init); | |
1520 | ||
1521 | #endif |