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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 | */ | |
72576341 | 19 | #define pr_fmt(fmt) "trace_kprobe: " fmt |
413d37d1 MH |
20 | |
21 | #include <linux/module.h> | |
22 | #include <linux/uaccess.h> | |
b2d09103 | 23 | #include <linux/rculist.h> |
540adea3 | 24 | #include <linux/error-injection.h> |
413d37d1 | 25 | |
8ab83f56 | 26 | #include "trace_probe.h" |
1ff511e3 | 27 | |
8ab83f56 | 28 | #define KPROBE_EVENT_SYSTEM "kprobes" |
696ced4f | 29 | #define KRETPROBE_MAXACTIVE_MAX 4096 |
e09c8614 | 30 | |
413d37d1 | 31 | /** |
77b44d1b | 32 | * Kprobe event core functions |
413d37d1 | 33 | */ |
c31ffb3f | 34 | struct trace_kprobe { |
413d37d1 | 35 | struct list_head list; |
4a846b44 | 36 | struct kretprobe rp; /* Use rp.kp for kprobe use */ |
a7636d9e | 37 | unsigned long __percpu *nhit; |
413d37d1 | 38 | const char *symbol; /* symbol name */ |
c31ffb3f | 39 | struct trace_probe tp; |
413d37d1 MH |
40 | }; |
41 | ||
c31ffb3f NK |
42 | #define SIZEOF_TRACE_KPROBE(n) \ |
43 | (offsetof(struct trace_kprobe, tp.args) + \ | |
eca0d916 | 44 | (sizeof(struct probe_arg) * (n))) |
a82378d8 | 45 | |
3da0f180 | 46 | static nokprobe_inline bool trace_kprobe_is_return(struct trace_kprobe *tk) |
413d37d1 | 47 | { |
c31ffb3f | 48 | return tk->rp.handler != NULL; |
413d37d1 MH |
49 | } |
50 | ||
3da0f180 | 51 | static nokprobe_inline const char *trace_kprobe_symbol(struct trace_kprobe *tk) |
413d37d1 | 52 | { |
c31ffb3f | 53 | return tk->symbol ? tk->symbol : "unknown"; |
413d37d1 MH |
54 | } |
55 | ||
3da0f180 | 56 | static nokprobe_inline unsigned long trace_kprobe_offset(struct trace_kprobe *tk) |
61424318 | 57 | { |
c31ffb3f | 58 | return tk->rp.kp.offset; |
61424318 MH |
59 | } |
60 | ||
3da0f180 | 61 | static nokprobe_inline bool trace_kprobe_has_gone(struct trace_kprobe *tk) |
61424318 | 62 | { |
c31ffb3f | 63 | return !!(kprobe_gone(&tk->rp.kp)); |
61424318 MH |
64 | } |
65 | ||
3da0f180 | 66 | static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk, |
c31ffb3f | 67 | struct module *mod) |
61424318 MH |
68 | { |
69 | int len = strlen(mod->name); | |
c31ffb3f | 70 | const char *name = trace_kprobe_symbol(tk); |
61424318 MH |
71 | return strncmp(mod->name, name, len) == 0 && name[len] == ':'; |
72 | } | |
73 | ||
3da0f180 | 74 | static nokprobe_inline bool trace_kprobe_is_on_module(struct trace_kprobe *tk) |
61424318 | 75 | { |
c31ffb3f | 76 | return !!strchr(trace_kprobe_symbol(tk), ':'); |
61424318 MH |
77 | } |
78 | ||
f18f97ac MN |
79 | static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe *tk) |
80 | { | |
81 | unsigned long nhit = 0; | |
82 | int cpu; | |
83 | ||
84 | for_each_possible_cpu(cpu) | |
85 | nhit += *per_cpu_ptr(tk->nhit, cpu); | |
86 | ||
87 | return nhit; | |
88 | } | |
89 | ||
b4da3340 | 90 | bool trace_kprobe_on_func_entry(struct trace_event_call *call) |
9802d865 JB |
91 | { |
92 | struct trace_kprobe *tk = (struct trace_kprobe *)call->data; | |
b4da3340 MH |
93 | |
94 | return kprobe_on_func_entry(tk->rp.kp.addr, | |
95 | tk->rp.kp.addr ? NULL : tk->rp.kp.symbol_name, | |
96 | tk->rp.kp.addr ? 0 : tk->rp.kp.offset); | |
9802d865 JB |
97 | } |
98 | ||
b4da3340 | 99 | bool trace_kprobe_error_injectable(struct trace_event_call *call) |
9802d865 JB |
100 | { |
101 | struct trace_kprobe *tk = (struct trace_kprobe *)call->data; | |
102 | unsigned long addr; | |
103 | ||
104 | if (tk->symbol) { | |
105 | addr = (unsigned long) | |
106 | kallsyms_lookup_name(trace_kprobe_symbol(tk)); | |
107 | addr += tk->rp.kp.offset; | |
108 | } else { | |
109 | addr = (unsigned long)tk->rp.kp.addr; | |
110 | } | |
540adea3 | 111 | return within_error_injection_list(addr); |
9802d865 JB |
112 | } |
113 | ||
c31ffb3f NK |
114 | static int register_kprobe_event(struct trace_kprobe *tk); |
115 | static int unregister_kprobe_event(struct trace_kprobe *tk); | |
413d37d1 MH |
116 | |
117 | static DEFINE_MUTEX(probe_lock); | |
118 | static LIST_HEAD(probe_list); | |
119 | ||
50d78056 MH |
120 | static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs); |
121 | static int kretprobe_dispatcher(struct kretprobe_instance *ri, | |
122 | struct pt_regs *regs); | |
123 | ||
1301a44e NK |
124 | /* Memory fetching by symbol */ |
125 | struct symbol_cache { | |
126 | char *symbol; | |
127 | long offset; | |
128 | unsigned long addr; | |
129 | }; | |
130 | ||
131 | unsigned long update_symbol_cache(struct symbol_cache *sc) | |
132 | { | |
133 | sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol); | |
134 | ||
135 | if (sc->addr) | |
136 | sc->addr += sc->offset; | |
137 | ||
138 | return sc->addr; | |
139 | } | |
140 | ||
141 | void free_symbol_cache(struct symbol_cache *sc) | |
142 | { | |
143 | kfree(sc->symbol); | |
144 | kfree(sc); | |
145 | } | |
146 | ||
147 | struct symbol_cache *alloc_symbol_cache(const char *sym, long offset) | |
148 | { | |
149 | struct symbol_cache *sc; | |
150 | ||
151 | if (!sym || strlen(sym) == 0) | |
152 | return NULL; | |
153 | ||
154 | sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL); | |
155 | if (!sc) | |
156 | return NULL; | |
157 | ||
158 | sc->symbol = kstrdup(sym, GFP_KERNEL); | |
159 | if (!sc->symbol) { | |
160 | kfree(sc); | |
161 | return NULL; | |
162 | } | |
163 | sc->offset = offset; | |
164 | update_symbol_cache(sc); | |
165 | ||
166 | return sc; | |
167 | } | |
168 | ||
3fd996a2 NK |
169 | /* |
170 | * Kprobes-specific fetch functions | |
171 | */ | |
172 | #define DEFINE_FETCH_stack(type) \ | |
3da0f180 | 173 | static void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs, \ |
3fd996a2 NK |
174 | void *offset, void *dest) \ |
175 | { \ | |
176 | *(type *)dest = (type)regs_get_kernel_stack_nth(regs, \ | |
177 | (unsigned int)((unsigned long)offset)); \ | |
3da0f180 MH |
178 | } \ |
179 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(stack, type)); | |
180 | ||
3fd996a2 NK |
181 | DEFINE_BASIC_FETCH_FUNCS(stack) |
182 | /* No string on the stack entry */ | |
183 | #define fetch_stack_string NULL | |
184 | #define fetch_stack_string_size NULL | |
185 | ||
5baaa59e | 186 | #define DEFINE_FETCH_memory(type) \ |
3da0f180 | 187 | static void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs, \ |
5baaa59e NK |
188 | void *addr, void *dest) \ |
189 | { \ | |
190 | type retval; \ | |
191 | if (probe_kernel_address(addr, retval)) \ | |
192 | *(type *)dest = 0; \ | |
193 | else \ | |
194 | *(type *)dest = retval; \ | |
3da0f180 MH |
195 | } \ |
196 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(memory, type)); | |
197 | ||
5baaa59e NK |
198 | DEFINE_BASIC_FETCH_FUNCS(memory) |
199 | /* | |
200 | * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max | |
201 | * length and relative data location. | |
202 | */ | |
3da0f180 MH |
203 | static void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs, |
204 | void *addr, void *dest) | |
5baaa59e | 205 | { |
5baaa59e NK |
206 | int maxlen = get_rloc_len(*(u32 *)dest); |
207 | u8 *dst = get_rloc_data(dest); | |
1a6877b9 | 208 | long ret; |
5baaa59e NK |
209 | |
210 | if (!maxlen) | |
211 | return; | |
212 | ||
213 | /* | |
214 | * Try to get string again, since the string can be changed while | |
215 | * probing. | |
216 | */ | |
1a6877b9 | 217 | ret = strncpy_from_unsafe(dst, addr, maxlen); |
5baaa59e NK |
218 | |
219 | if (ret < 0) { /* Failed to fetch string */ | |
1a6877b9 | 220 | dst[0] = '\0'; |
5baaa59e NK |
221 | *(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest)); |
222 | } else { | |
1a6877b9 | 223 | *(u32 *)dest = make_data_rloc(ret, get_rloc_offs(*(u32 *)dest)); |
5baaa59e NK |
224 | } |
225 | } | |
3da0f180 | 226 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(memory, string)); |
5baaa59e NK |
227 | |
228 | /* Return the length of string -- including null terminal byte */ | |
3da0f180 MH |
229 | static void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs, |
230 | void *addr, void *dest) | |
5baaa59e NK |
231 | { |
232 | mm_segment_t old_fs; | |
233 | int ret, len = 0; | |
234 | u8 c; | |
235 | ||
236 | old_fs = get_fs(); | |
237 | set_fs(KERNEL_DS); | |
238 | pagefault_disable(); | |
239 | ||
240 | do { | |
241 | ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1); | |
242 | len++; | |
243 | } while (c && ret == 0 && len < MAX_STRING_SIZE); | |
244 | ||
245 | pagefault_enable(); | |
246 | set_fs(old_fs); | |
247 | ||
248 | if (ret < 0) /* Failed to check the length */ | |
249 | *(u32 *)dest = 0; | |
250 | else | |
251 | *(u32 *)dest = len; | |
252 | } | |
3da0f180 | 253 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(memory, string_size)); |
5baaa59e | 254 | |
1301a44e | 255 | #define DEFINE_FETCH_symbol(type) \ |
3da0f180 | 256 | void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs, void *data, void *dest)\ |
1301a44e NK |
257 | { \ |
258 | struct symbol_cache *sc = data; \ | |
259 | if (sc->addr) \ | |
260 | fetch_memory_##type(regs, (void *)sc->addr, dest); \ | |
261 | else \ | |
262 | *(type *)dest = 0; \ | |
3da0f180 MH |
263 | } \ |
264 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(symbol, type)); | |
265 | ||
1301a44e NK |
266 | DEFINE_BASIC_FETCH_FUNCS(symbol) |
267 | DEFINE_FETCH_symbol(string) | |
268 | DEFINE_FETCH_symbol(string_size) | |
269 | ||
b7e0bf34 NK |
270 | /* kprobes don't support file_offset fetch methods */ |
271 | #define fetch_file_offset_u8 NULL | |
272 | #define fetch_file_offset_u16 NULL | |
273 | #define fetch_file_offset_u32 NULL | |
274 | #define fetch_file_offset_u64 NULL | |
275 | #define fetch_file_offset_string NULL | |
276 | #define fetch_file_offset_string_size NULL | |
277 | ||
34fee3a1 | 278 | /* Fetch type information table */ |
d9a16d3a | 279 | static const struct fetch_type kprobes_fetch_type_table[] = { |
34fee3a1 NK |
280 | /* Special types */ |
281 | [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string, | |
282 | sizeof(u32), 1, "__data_loc char[]"), | |
283 | [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32, | |
284 | string_size, sizeof(u32), 0, "u32"), | |
285 | /* Basic types */ | |
286 | ASSIGN_FETCH_TYPE(u8, u8, 0), | |
287 | ASSIGN_FETCH_TYPE(u16, u16, 0), | |
288 | ASSIGN_FETCH_TYPE(u32, u32, 0), | |
289 | ASSIGN_FETCH_TYPE(u64, u64, 0), | |
290 | ASSIGN_FETCH_TYPE(s8, u8, 1), | |
291 | ASSIGN_FETCH_TYPE(s16, u16, 1), | |
292 | ASSIGN_FETCH_TYPE(s32, u32, 1), | |
293 | ASSIGN_FETCH_TYPE(s64, u64, 1), | |
17ce3dc7 MH |
294 | ASSIGN_FETCH_TYPE_ALIAS(x8, u8, u8, 0), |
295 | ASSIGN_FETCH_TYPE_ALIAS(x16, u16, u16, 0), | |
296 | ASSIGN_FETCH_TYPE_ALIAS(x32, u32, u32, 0), | |
297 | ASSIGN_FETCH_TYPE_ALIAS(x64, u64, u64, 0), | |
34fee3a1 NK |
298 | |
299 | ASSIGN_FETCH_TYPE_END | |
300 | }; | |
301 | ||
4a846b44 MH |
302 | /* |
303 | * Allocate new trace_probe and initialize it (including kprobes). | |
304 | */ | |
c31ffb3f | 305 | static struct trace_kprobe *alloc_trace_kprobe(const char *group, |
f52487e9 | 306 | const char *event, |
4a846b44 MH |
307 | void *addr, |
308 | const char *symbol, | |
309 | unsigned long offs, | |
696ced4f | 310 | int maxactive, |
3a6b7666 | 311 | int nargs, bool is_return) |
413d37d1 | 312 | { |
c31ffb3f | 313 | struct trace_kprobe *tk; |
6f3cf440 | 314 | int ret = -ENOMEM; |
413d37d1 | 315 | |
c31ffb3f NK |
316 | tk = kzalloc(SIZEOF_TRACE_KPROBE(nargs), GFP_KERNEL); |
317 | if (!tk) | |
6f3cf440 | 318 | return ERR_PTR(ret); |
413d37d1 | 319 | |
a7636d9e MKL |
320 | tk->nhit = alloc_percpu(unsigned long); |
321 | if (!tk->nhit) | |
322 | goto error; | |
323 | ||
413d37d1 | 324 | if (symbol) { |
c31ffb3f NK |
325 | tk->symbol = kstrdup(symbol, GFP_KERNEL); |
326 | if (!tk->symbol) | |
413d37d1 | 327 | goto error; |
c31ffb3f NK |
328 | tk->rp.kp.symbol_name = tk->symbol; |
329 | tk->rp.kp.offset = offs; | |
4a846b44 | 330 | } else |
c31ffb3f | 331 | tk->rp.kp.addr = addr; |
4a846b44 MH |
332 | |
333 | if (is_return) | |
c31ffb3f | 334 | tk->rp.handler = kretprobe_dispatcher; |
4a846b44 | 335 | else |
c31ffb3f | 336 | tk->rp.kp.pre_handler = kprobe_dispatcher; |
4a846b44 | 337 | |
696ced4f AC |
338 | tk->rp.maxactive = maxactive; |
339 | ||
da34634f | 340 | if (!event || !is_good_name(event)) { |
6f3cf440 | 341 | ret = -EINVAL; |
4263565d | 342 | goto error; |
6f3cf440 MH |
343 | } |
344 | ||
c31ffb3f NK |
345 | tk->tp.call.class = &tk->tp.class; |
346 | tk->tp.call.name = kstrdup(event, GFP_KERNEL); | |
347 | if (!tk->tp.call.name) | |
4263565d | 348 | goto error; |
413d37d1 | 349 | |
da34634f | 350 | if (!group || !is_good_name(group)) { |
6f3cf440 | 351 | ret = -EINVAL; |
f52487e9 | 352 | goto error; |
6f3cf440 MH |
353 | } |
354 | ||
c31ffb3f NK |
355 | tk->tp.class.system = kstrdup(group, GFP_KERNEL); |
356 | if (!tk->tp.class.system) | |
f52487e9 MH |
357 | goto error; |
358 | ||
c31ffb3f NK |
359 | INIT_LIST_HEAD(&tk->list); |
360 | INIT_LIST_HEAD(&tk->tp.files); | |
361 | return tk; | |
413d37d1 | 362 | error: |
c31ffb3f NK |
363 | kfree(tk->tp.call.name); |
364 | kfree(tk->symbol); | |
a7636d9e | 365 | free_percpu(tk->nhit); |
c31ffb3f | 366 | kfree(tk); |
6f3cf440 | 367 | return ERR_PTR(ret); |
413d37d1 MH |
368 | } |
369 | ||
c31ffb3f | 370 | static void free_trace_kprobe(struct trace_kprobe *tk) |
413d37d1 MH |
371 | { |
372 | int i; | |
373 | ||
c31ffb3f NK |
374 | for (i = 0; i < tk->tp.nr_args; i++) |
375 | traceprobe_free_probe_arg(&tk->tp.args[i]); | |
413d37d1 | 376 | |
c31ffb3f NK |
377 | kfree(tk->tp.call.class->system); |
378 | kfree(tk->tp.call.name); | |
379 | kfree(tk->symbol); | |
a7636d9e | 380 | free_percpu(tk->nhit); |
c31ffb3f | 381 | kfree(tk); |
413d37d1 MH |
382 | } |
383 | ||
c31ffb3f NK |
384 | static struct trace_kprobe *find_trace_kprobe(const char *event, |
385 | const char *group) | |
413d37d1 | 386 | { |
c31ffb3f | 387 | struct trace_kprobe *tk; |
413d37d1 | 388 | |
c31ffb3f | 389 | list_for_each_entry(tk, &probe_list, list) |
687fcc4a | 390 | if (strcmp(trace_event_name(&tk->tp.call), event) == 0 && |
c31ffb3f NK |
391 | strcmp(tk->tp.call.class->system, group) == 0) |
392 | return tk; | |
413d37d1 MH |
393 | return NULL; |
394 | } | |
395 | ||
41a7dd42 MH |
396 | /* |
397 | * Enable trace_probe | |
398 | * if the file is NULL, enable "perf" handler, or enable "trace" handler. | |
399 | */ | |
400 | static int | |
7f1d2f82 | 401 | enable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file) |
1538f888 MH |
402 | { |
403 | int ret = 0; | |
404 | ||
41a7dd42 | 405 | if (file) { |
b04d52e3 ON |
406 | struct event_file_link *link; |
407 | ||
408 | link = kmalloc(sizeof(*link), GFP_KERNEL); | |
409 | if (!link) { | |
41a7dd42 | 410 | ret = -ENOMEM; |
3fe3d619 | 411 | goto out; |
41a7dd42 | 412 | } |
41a7dd42 | 413 | |
b04d52e3 | 414 | link->file = file; |
c31ffb3f | 415 | list_add_tail_rcu(&link->list, &tk->tp.files); |
41a7dd42 | 416 | |
c31ffb3f | 417 | tk->tp.flags |= TP_FLAG_TRACE; |
41a7dd42 | 418 | } else |
c31ffb3f | 419 | tk->tp.flags |= TP_FLAG_PROFILE; |
41a7dd42 | 420 | |
c31ffb3f NK |
421 | if (trace_probe_is_registered(&tk->tp) && !trace_kprobe_has_gone(tk)) { |
422 | if (trace_kprobe_is_return(tk)) | |
423 | ret = enable_kretprobe(&tk->rp); | |
1538f888 | 424 | else |
c31ffb3f | 425 | ret = enable_kprobe(&tk->rp.kp); |
1538f888 | 426 | } |
3fe3d619 | 427 | out: |
1538f888 MH |
428 | return ret; |
429 | } | |
430 | ||
41a7dd42 MH |
431 | /* |
432 | * Disable trace_probe | |
433 | * if the file is NULL, disable "perf" handler, or disable "trace" handler. | |
434 | */ | |
435 | static int | |
7f1d2f82 | 436 | disable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file) |
1538f888 | 437 | { |
a232e270 MH |
438 | struct event_file_link *link = NULL; |
439 | int wait = 0; | |
41a7dd42 MH |
440 | int ret = 0; |
441 | ||
41a7dd42 | 442 | if (file) { |
c31ffb3f | 443 | link = find_event_file_link(&tk->tp, file); |
b04d52e3 | 444 | if (!link) { |
41a7dd42 | 445 | ret = -EINVAL; |
3fe3d619 | 446 | goto out; |
41a7dd42 MH |
447 | } |
448 | ||
b04d52e3 | 449 | list_del_rcu(&link->list); |
a232e270 | 450 | wait = 1; |
c31ffb3f | 451 | if (!list_empty(&tk->tp.files)) |
b04d52e3 | 452 | goto out; |
41a7dd42 | 453 | |
c31ffb3f | 454 | tk->tp.flags &= ~TP_FLAG_TRACE; |
41a7dd42 | 455 | } else |
c31ffb3f | 456 | tk->tp.flags &= ~TP_FLAG_PROFILE; |
41a7dd42 | 457 | |
c31ffb3f NK |
458 | if (!trace_probe_is_enabled(&tk->tp) && trace_probe_is_registered(&tk->tp)) { |
459 | if (trace_kprobe_is_return(tk)) | |
460 | disable_kretprobe(&tk->rp); | |
1538f888 | 461 | else |
c31ffb3f | 462 | disable_kprobe(&tk->rp.kp); |
a232e270 | 463 | wait = 1; |
1538f888 | 464 | } |
3fe3d619 | 465 | out: |
a232e270 MH |
466 | if (wait) { |
467 | /* | |
468 | * Synchronize with kprobe_trace_func/kretprobe_trace_func | |
469 | * to ensure disabled (all running handlers are finished). | |
470 | * This is not only for kfree(), but also the caller, | |
471 | * trace_remove_event_call() supposes it for releasing | |
472 | * event_call related objects, which will be accessed in | |
473 | * the kprobe_trace_func/kretprobe_trace_func. | |
474 | */ | |
475 | synchronize_sched(); | |
476 | kfree(link); /* Ignored if link == NULL */ | |
477 | } | |
478 | ||
41a7dd42 | 479 | return ret; |
1538f888 MH |
480 | } |
481 | ||
61424318 | 482 | /* Internal register function - just handle k*probes and flags */ |
c31ffb3f | 483 | static int __register_trace_kprobe(struct trace_kprobe *tk) |
413d37d1 | 484 | { |
7f6878a3 | 485 | int i, ret; |
61424318 | 486 | |
c31ffb3f | 487 | if (trace_probe_is_registered(&tk->tp)) |
61424318 MH |
488 | return -EINVAL; |
489 | ||
c31ffb3f NK |
490 | for (i = 0; i < tk->tp.nr_args; i++) |
491 | traceprobe_update_arg(&tk->tp.args[i]); | |
7f6878a3 | 492 | |
61424318 | 493 | /* Set/clear disabled flag according to tp->flag */ |
c31ffb3f NK |
494 | if (trace_probe_is_enabled(&tk->tp)) |
495 | tk->rp.kp.flags &= ~KPROBE_FLAG_DISABLED; | |
61424318 | 496 | else |
c31ffb3f | 497 | tk->rp.kp.flags |= KPROBE_FLAG_DISABLED; |
61424318 | 498 | |
c31ffb3f NK |
499 | if (trace_kprobe_is_return(tk)) |
500 | ret = register_kretprobe(&tk->rp); | |
413d37d1 | 501 | else |
c31ffb3f | 502 | ret = register_kprobe(&tk->rp.kp); |
61424318 MH |
503 | |
504 | if (ret == 0) | |
c31ffb3f | 505 | tk->tp.flags |= TP_FLAG_REGISTERED; |
61424318 | 506 | else { |
a395d6a7 JP |
507 | pr_warn("Could not insert probe at %s+%lu: %d\n", |
508 | trace_kprobe_symbol(tk), trace_kprobe_offset(tk), ret); | |
c31ffb3f | 509 | if (ret == -ENOENT && trace_kprobe_is_on_module(tk)) { |
a395d6a7 | 510 | pr_warn("This probe might be able to register after target module is loaded. Continue.\n"); |
61424318 MH |
511 | ret = 0; |
512 | } else if (ret == -EILSEQ) { | |
a395d6a7 JP |
513 | pr_warn("Probing address(0x%p) is not an instruction boundary.\n", |
514 | tk->rp.kp.addr); | |
61424318 MH |
515 | ret = -EINVAL; |
516 | } | |
517 | } | |
518 | ||
519 | return ret; | |
520 | } | |
521 | ||
522 | /* Internal unregister function - just handle k*probes and flags */ | |
c31ffb3f | 523 | static void __unregister_trace_kprobe(struct trace_kprobe *tk) |
61424318 | 524 | { |
c31ffb3f NK |
525 | if (trace_probe_is_registered(&tk->tp)) { |
526 | if (trace_kprobe_is_return(tk)) | |
527 | unregister_kretprobe(&tk->rp); | |
61424318 | 528 | else |
c31ffb3f NK |
529 | unregister_kprobe(&tk->rp.kp); |
530 | tk->tp.flags &= ~TP_FLAG_REGISTERED; | |
61424318 | 531 | /* Cleanup kprobe for reuse */ |
c31ffb3f NK |
532 | if (tk->rp.kp.symbol_name) |
533 | tk->rp.kp.addr = NULL; | |
61424318 MH |
534 | } |
535 | } | |
536 | ||
537 | /* Unregister a trace_probe and probe_event: call with locking probe_lock */ | |
c31ffb3f | 538 | static int unregister_trace_kprobe(struct trace_kprobe *tk) |
61424318 | 539 | { |
02ca1521 | 540 | /* Enabled event can not be unregistered */ |
c31ffb3f | 541 | if (trace_probe_is_enabled(&tk->tp)) |
02ca1521 MH |
542 | return -EBUSY; |
543 | ||
40c32592 | 544 | /* Will fail if probe is being used by ftrace or perf */ |
c31ffb3f | 545 | if (unregister_kprobe_event(tk)) |
40c32592 SRRH |
546 | return -EBUSY; |
547 | ||
c31ffb3f NK |
548 | __unregister_trace_kprobe(tk); |
549 | list_del(&tk->list); | |
02ca1521 MH |
550 | |
551 | return 0; | |
413d37d1 MH |
552 | } |
553 | ||
554 | /* Register a trace_probe and probe_event */ | |
c31ffb3f | 555 | static int register_trace_kprobe(struct trace_kprobe *tk) |
413d37d1 | 556 | { |
c31ffb3f | 557 | struct trace_kprobe *old_tk; |
413d37d1 MH |
558 | int ret; |
559 | ||
560 | mutex_lock(&probe_lock); | |
561 | ||
61424318 | 562 | /* Delete old (same name) event if exist */ |
687fcc4a | 563 | old_tk = find_trace_kprobe(trace_event_name(&tk->tp.call), |
de7b2973 | 564 | tk->tp.call.class->system); |
c31ffb3f NK |
565 | if (old_tk) { |
566 | ret = unregister_trace_kprobe(old_tk); | |
02ca1521 MH |
567 | if (ret < 0) |
568 | goto end; | |
c31ffb3f | 569 | free_trace_kprobe(old_tk); |
2d5e067e | 570 | } |
61424318 MH |
571 | |
572 | /* Register new event */ | |
c31ffb3f | 573 | ret = register_kprobe_event(tk); |
2d5e067e | 574 | if (ret) { |
a395d6a7 | 575 | pr_warn("Failed to register probe event(%d)\n", ret); |
2d5e067e MH |
576 | goto end; |
577 | } | |
578 | ||
61424318 | 579 | /* Register k*probe */ |
c31ffb3f | 580 | ret = __register_trace_kprobe(tk); |
61424318 | 581 | if (ret < 0) |
c31ffb3f | 582 | unregister_kprobe_event(tk); |
61424318 | 583 | else |
c31ffb3f | 584 | list_add_tail(&tk->list, &probe_list); |
61424318 | 585 | |
413d37d1 MH |
586 | end: |
587 | mutex_unlock(&probe_lock); | |
588 | return ret; | |
589 | } | |
590 | ||
61424318 | 591 | /* Module notifier call back, checking event on the module */ |
c31ffb3f | 592 | static int trace_kprobe_module_callback(struct notifier_block *nb, |
61424318 MH |
593 | unsigned long val, void *data) |
594 | { | |
595 | struct module *mod = data; | |
c31ffb3f | 596 | struct trace_kprobe *tk; |
61424318 MH |
597 | int ret; |
598 | ||
599 | if (val != MODULE_STATE_COMING) | |
600 | return NOTIFY_DONE; | |
601 | ||
602 | /* Update probes on coming module */ | |
603 | mutex_lock(&probe_lock); | |
c31ffb3f NK |
604 | list_for_each_entry(tk, &probe_list, list) { |
605 | if (trace_kprobe_within_module(tk, mod)) { | |
02ca1521 | 606 | /* Don't need to check busy - this should have gone. */ |
c31ffb3f NK |
607 | __unregister_trace_kprobe(tk); |
608 | ret = __register_trace_kprobe(tk); | |
61424318 | 609 | if (ret) |
a395d6a7 JP |
610 | pr_warn("Failed to re-register probe %s on %s: %d\n", |
611 | trace_event_name(&tk->tp.call), | |
612 | mod->name, ret); | |
61424318 MH |
613 | } |
614 | } | |
615 | mutex_unlock(&probe_lock); | |
616 | ||
617 | return NOTIFY_DONE; | |
618 | } | |
619 | ||
c31ffb3f NK |
620 | static struct notifier_block trace_kprobe_module_nb = { |
621 | .notifier_call = trace_kprobe_module_callback, | |
61424318 MH |
622 | .priority = 1 /* Invoked after kprobe module callback */ |
623 | }; | |
624 | ||
fca18a47 NR |
625 | /* Convert certain expected symbols into '_' when generating event names */ |
626 | static inline void sanitize_event_name(char *name) | |
627 | { | |
628 | while (*name++ != '\0') | |
629 | if (*name == ':' || *name == '.') | |
630 | *name = '_'; | |
631 | } | |
632 | ||
c31ffb3f | 633 | static int create_trace_kprobe(int argc, char **argv) |
413d37d1 MH |
634 | { |
635 | /* | |
636 | * Argument syntax: | |
696ced4f AC |
637 | * - Add kprobe: |
638 | * p[:[GRP/]EVENT] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS] | |
639 | * - Add kretprobe: | |
640 | * r[MAXACTIVE][:[GRP/]EVENT] [MOD:]KSYM[+0] [FETCHARGS] | |
413d37d1 | 641 | * Fetch args: |
2e06ff63 MH |
642 | * $retval : fetch return value |
643 | * $stack : fetch stack address | |
644 | * $stackN : fetch Nth of stack (N:0-) | |
35abb67d | 645 | * $comm : fetch current task comm |
413d37d1 MH |
646 | * @ADDR : fetch memory at ADDR (ADDR should be in kernel) |
647 | * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol) | |
648 | * %REG : fetch register REG | |
93ccae7a | 649 | * Dereferencing memory fetch: |
413d37d1 | 650 | * +|-offs(ARG) : fetch memory at ARG +|- offs address. |
eca0d916 MH |
651 | * Alias name of args: |
652 | * NAME=FETCHARG : set NAME as alias of FETCHARG. | |
93ccae7a MH |
653 | * Type of args: |
654 | * FETCHARG:TYPE : use TYPE instead of unsigned long. | |
413d37d1 | 655 | */ |
c31ffb3f | 656 | struct trace_kprobe *tk; |
413d37d1 | 657 | int i, ret = 0; |
3a6b7666 | 658 | bool is_return = false, is_delete = false; |
93ccae7a | 659 | char *symbol = NULL, *event = NULL, *group = NULL; |
696ced4f | 660 | int maxactive = 0; |
da34634f | 661 | char *arg; |
c5d343b6 | 662 | long offset = 0; |
413d37d1 | 663 | void *addr = NULL; |
4a846b44 | 664 | char buf[MAX_EVENT_NAME_LEN]; |
413d37d1 | 665 | |
a7c312be | 666 | /* argc must be >= 1 */ |
413d37d1 | 667 | if (argv[0][0] == 'p') |
3a6b7666 | 668 | is_return = false; |
413d37d1 | 669 | else if (argv[0][0] == 'r') |
3a6b7666 | 670 | is_return = true; |
a7c312be | 671 | else if (argv[0][0] == '-') |
3a6b7666 | 672 | is_delete = true; |
e63cc239 | 673 | else { |
a7c312be MH |
674 | pr_info("Probe definition must be started with 'p', 'r' or" |
675 | " '-'.\n"); | |
413d37d1 | 676 | return -EINVAL; |
e63cc239 | 677 | } |
413d37d1 | 678 | |
696ced4f AC |
679 | event = strchr(&argv[0][1], ':'); |
680 | if (event) { | |
681 | event[0] = '\0'; | |
682 | event++; | |
683 | } | |
684 | if (is_return && isdigit(argv[0][1])) { | |
685 | ret = kstrtouint(&argv[0][1], 0, &maxactive); | |
686 | if (ret) { | |
687 | pr_info("Failed to parse maxactive.\n"); | |
688 | return ret; | |
689 | } | |
690 | /* kretprobes instances are iterated over via a list. The | |
691 | * maximum should stay reasonable. | |
692 | */ | |
693 | if (maxactive > KRETPROBE_MAXACTIVE_MAX) { | |
694 | pr_info("Maxactive is too big (%d > %d).\n", | |
695 | maxactive, KRETPROBE_MAXACTIVE_MAX); | |
696 | return -E2BIG; | |
697 | } | |
698 | } | |
699 | ||
700 | if (event) { | |
f52487e9 MH |
701 | if (strchr(event, '/')) { |
702 | group = event; | |
703 | event = strchr(group, '/') + 1; | |
704 | event[-1] = '\0'; | |
705 | if (strlen(group) == 0) { | |
a5efd925 | 706 | pr_info("Group name is not specified\n"); |
f52487e9 MH |
707 | return -EINVAL; |
708 | } | |
709 | } | |
413d37d1 | 710 | if (strlen(event) == 0) { |
a5efd925 | 711 | pr_info("Event name is not specified\n"); |
413d37d1 MH |
712 | return -EINVAL; |
713 | } | |
714 | } | |
a7c312be MH |
715 | if (!group) |
716 | group = KPROBE_EVENT_SYSTEM; | |
413d37d1 | 717 | |
a7c312be MH |
718 | if (is_delete) { |
719 | if (!event) { | |
720 | pr_info("Delete command needs an event name.\n"); | |
721 | return -EINVAL; | |
722 | } | |
9da79ab8 | 723 | mutex_lock(&probe_lock); |
c31ffb3f NK |
724 | tk = find_trace_kprobe(event, group); |
725 | if (!tk) { | |
9da79ab8 | 726 | mutex_unlock(&probe_lock); |
a7c312be MH |
727 | pr_info("Event %s/%s doesn't exist.\n", group, event); |
728 | return -ENOENT; | |
729 | } | |
730 | /* delete an event */ | |
c31ffb3f | 731 | ret = unregister_trace_kprobe(tk); |
02ca1521 | 732 | if (ret == 0) |
c31ffb3f | 733 | free_trace_kprobe(tk); |
9da79ab8 | 734 | mutex_unlock(&probe_lock); |
02ca1521 | 735 | return ret; |
a7c312be MH |
736 | } |
737 | ||
738 | if (argc < 2) { | |
739 | pr_info("Probe point is not specified.\n"); | |
740 | return -EINVAL; | |
741 | } | |
9e52b325 SD |
742 | |
743 | /* try to parse an address. if that fails, try to read the | |
744 | * input as a symbol. */ | |
745 | if (kstrtoul(argv[1], 0, (unsigned long *)&addr)) { | |
413d37d1 MH |
746 | /* a symbol specified */ |
747 | symbol = argv[1]; | |
748 | /* TODO: support .init module functions */ | |
8ab83f56 | 749 | ret = traceprobe_split_symbol_offset(symbol, &offset); |
c5d343b6 | 750 | if (ret || offset < 0 || offset > UINT_MAX) { |
9e52b325 | 751 | pr_info("Failed to parse either an address or a symbol.\n"); |
413d37d1 | 752 | return ret; |
e63cc239 | 753 | } |
d0e02579 | 754 | if (offset && is_return && |
659b957f | 755 | !kprobe_on_func_entry(NULL, symbol, offset)) { |
d0e02579 | 756 | pr_info("Given offset is not valid for return probe.\n"); |
413d37d1 | 757 | return -EINVAL; |
e63cc239 | 758 | } |
413d37d1 | 759 | } |
a82378d8 | 760 | argc -= 2; argv += 2; |
413d37d1 MH |
761 | |
762 | /* setup a probe */ | |
4263565d MH |
763 | if (!event) { |
764 | /* Make a new event name */ | |
4263565d | 765 | if (symbol) |
6f3cf440 | 766 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld", |
4263565d MH |
767 | is_return ? 'r' : 'p', symbol, offset); |
768 | else | |
6f3cf440 | 769 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p", |
4263565d | 770 | is_return ? 'r' : 'p', addr); |
fca18a47 | 771 | sanitize_event_name(buf); |
4a846b44 MH |
772 | event = buf; |
773 | } | |
696ced4f AC |
774 | tk = alloc_trace_kprobe(group, event, addr, symbol, offset, maxactive, |
775 | argc, is_return); | |
c31ffb3f | 776 | if (IS_ERR(tk)) { |
e63cc239 | 777 | pr_info("Failed to allocate trace_probe.(%d)\n", |
c31ffb3f NK |
778 | (int)PTR_ERR(tk)); |
779 | return PTR_ERR(tk); | |
e63cc239 | 780 | } |
413d37d1 | 781 | |
413d37d1 | 782 | /* parse arguments */ |
a82378d8 MH |
783 | ret = 0; |
784 | for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { | |
c31ffb3f NK |
785 | struct probe_arg *parg = &tk->tp.args[i]; |
786 | ||
61a52736 | 787 | /* Increment count for freeing args in error case */ |
c31ffb3f | 788 | tk->tp.nr_args++; |
61a52736 | 789 | |
eca0d916 MH |
790 | /* Parse argument name */ |
791 | arg = strchr(argv[i], '='); | |
aba91595 | 792 | if (arg) { |
eca0d916 | 793 | *arg++ = '\0'; |
c31ffb3f | 794 | parg->name = kstrdup(argv[i], GFP_KERNEL); |
aba91595 | 795 | } else { |
eca0d916 | 796 | arg = argv[i]; |
aba91595 MH |
797 | /* If argument name is omitted, set "argN" */ |
798 | snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1); | |
c31ffb3f | 799 | parg->name = kstrdup(buf, GFP_KERNEL); |
aba91595 | 800 | } |
a703d946 | 801 | |
c31ffb3f | 802 | if (!parg->name) { |
aba91595 | 803 | pr_info("Failed to allocate argument[%d] name.\n", i); |
ba8665d7 | 804 | ret = -ENOMEM; |
413d37d1 MH |
805 | goto error; |
806 | } | |
da34634f | 807 | |
c31ffb3f | 808 | if (!is_good_name(parg->name)) { |
da34634f | 809 | pr_info("Invalid argument[%d] name: %s\n", |
c31ffb3f | 810 | i, parg->name); |
da34634f MH |
811 | ret = -EINVAL; |
812 | goto error; | |
813 | } | |
93ccae7a | 814 | |
c31ffb3f NK |
815 | if (traceprobe_conflict_field_name(parg->name, |
816 | tk->tp.args, i)) { | |
aba91595 | 817 | pr_info("Argument[%d] name '%s' conflicts with " |
93ccae7a MH |
818 | "another field.\n", i, argv[i]); |
819 | ret = -EINVAL; | |
820 | goto error; | |
821 | } | |
ba8665d7 MH |
822 | |
823 | /* Parse fetch argument */ | |
c31ffb3f | 824 | ret = traceprobe_parse_probe_arg(arg, &tk->tp.size, parg, |
d9a16d3a SR |
825 | is_return, true, |
826 | kprobes_fetch_type_table); | |
e63cc239 | 827 | if (ret) { |
aba91595 | 828 | pr_info("Parse error at argument[%d]. (%d)\n", i, ret); |
413d37d1 | 829 | goto error; |
e63cc239 | 830 | } |
413d37d1 | 831 | } |
413d37d1 | 832 | |
c31ffb3f | 833 | ret = register_trace_kprobe(tk); |
413d37d1 MH |
834 | if (ret) |
835 | goto error; | |
836 | return 0; | |
837 | ||
838 | error: | |
c31ffb3f | 839 | free_trace_kprobe(tk); |
413d37d1 MH |
840 | return ret; |
841 | } | |
842 | ||
c31ffb3f | 843 | static int release_all_trace_kprobes(void) |
413d37d1 | 844 | { |
c31ffb3f | 845 | struct trace_kprobe *tk; |
02ca1521 | 846 | int ret = 0; |
413d37d1 MH |
847 | |
848 | mutex_lock(&probe_lock); | |
02ca1521 | 849 | /* Ensure no probe is in use. */ |
c31ffb3f NK |
850 | list_for_each_entry(tk, &probe_list, list) |
851 | if (trace_probe_is_enabled(&tk->tp)) { | |
02ca1521 MH |
852 | ret = -EBUSY; |
853 | goto end; | |
854 | } | |
413d37d1 MH |
855 | /* TODO: Use batch unregistration */ |
856 | while (!list_empty(&probe_list)) { | |
c31ffb3f NK |
857 | tk = list_entry(probe_list.next, struct trace_kprobe, list); |
858 | ret = unregister_trace_kprobe(tk); | |
40c32592 SRRH |
859 | if (ret) |
860 | goto end; | |
c31ffb3f | 861 | free_trace_kprobe(tk); |
413d37d1 | 862 | } |
02ca1521 MH |
863 | |
864 | end: | |
413d37d1 | 865 | mutex_unlock(&probe_lock); |
02ca1521 MH |
866 | |
867 | return ret; | |
413d37d1 MH |
868 | } |
869 | ||
413d37d1 MH |
870 | /* Probes listing interfaces */ |
871 | static void *probes_seq_start(struct seq_file *m, loff_t *pos) | |
872 | { | |
873 | mutex_lock(&probe_lock); | |
874 | return seq_list_start(&probe_list, *pos); | |
875 | } | |
876 | ||
877 | static void *probes_seq_next(struct seq_file *m, void *v, loff_t *pos) | |
878 | { | |
879 | return seq_list_next(v, &probe_list, pos); | |
880 | } | |
881 | ||
882 | static void probes_seq_stop(struct seq_file *m, void *v) | |
883 | { | |
884 | mutex_unlock(&probe_lock); | |
885 | } | |
886 | ||
887 | static int probes_seq_show(struct seq_file *m, void *v) | |
888 | { | |
c31ffb3f | 889 | struct trace_kprobe *tk = v; |
93ccae7a | 890 | int i; |
413d37d1 | 891 | |
fa6f0cc7 | 892 | seq_putc(m, trace_kprobe_is_return(tk) ? 'r' : 'p'); |
de7b2973 | 893 | seq_printf(m, ":%s/%s", tk->tp.call.class->system, |
687fcc4a | 894 | trace_event_name(&tk->tp.call)); |
413d37d1 | 895 | |
c31ffb3f NK |
896 | if (!tk->symbol) |
897 | seq_printf(m, " 0x%p", tk->rp.kp.addr); | |
898 | else if (tk->rp.kp.offset) | |
899 | seq_printf(m, " %s+%u", trace_kprobe_symbol(tk), | |
900 | tk->rp.kp.offset); | |
413d37d1 | 901 | else |
c31ffb3f | 902 | seq_printf(m, " %s", trace_kprobe_symbol(tk)); |
413d37d1 | 903 | |
c31ffb3f NK |
904 | for (i = 0; i < tk->tp.nr_args; i++) |
905 | seq_printf(m, " %s=%s", tk->tp.args[i].name, tk->tp.args[i].comm); | |
fa6f0cc7 | 906 | seq_putc(m, '\n'); |
93ccae7a | 907 | |
413d37d1 MH |
908 | return 0; |
909 | } | |
910 | ||
911 | static const struct seq_operations probes_seq_op = { | |
912 | .start = probes_seq_start, | |
913 | .next = probes_seq_next, | |
914 | .stop = probes_seq_stop, | |
915 | .show = probes_seq_show | |
916 | }; | |
917 | ||
918 | static int probes_open(struct inode *inode, struct file *file) | |
919 | { | |
02ca1521 MH |
920 | int ret; |
921 | ||
922 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { | |
c31ffb3f | 923 | ret = release_all_trace_kprobes(); |
02ca1521 MH |
924 | if (ret < 0) |
925 | return ret; | |
926 | } | |
413d37d1 MH |
927 | |
928 | return seq_open(file, &probes_seq_op); | |
929 | } | |
930 | ||
413d37d1 MH |
931 | static ssize_t probes_write(struct file *file, const char __user *buffer, |
932 | size_t count, loff_t *ppos) | |
933 | { | |
7e465baa TZ |
934 | return trace_parse_run_command(file, buffer, count, ppos, |
935 | create_trace_kprobe); | |
413d37d1 MH |
936 | } |
937 | ||
938 | static const struct file_operations kprobe_events_ops = { | |
939 | .owner = THIS_MODULE, | |
940 | .open = probes_open, | |
941 | .read = seq_read, | |
942 | .llseek = seq_lseek, | |
943 | .release = seq_release, | |
944 | .write = probes_write, | |
945 | }; | |
946 | ||
cd7e7bd5 MH |
947 | /* Probes profiling interfaces */ |
948 | static int probes_profile_seq_show(struct seq_file *m, void *v) | |
949 | { | |
c31ffb3f | 950 | struct trace_kprobe *tk = v; |
cd7e7bd5 | 951 | |
de7b2973 | 952 | seq_printf(m, " %-44s %15lu %15lu\n", |
f18f97ac MN |
953 | trace_event_name(&tk->tp.call), |
954 | trace_kprobe_nhit(tk), | |
c31ffb3f | 955 | tk->rp.kp.nmissed); |
cd7e7bd5 MH |
956 | |
957 | return 0; | |
958 | } | |
959 | ||
960 | static const struct seq_operations profile_seq_op = { | |
961 | .start = probes_seq_start, | |
962 | .next = probes_seq_next, | |
963 | .stop = probes_seq_stop, | |
964 | .show = probes_profile_seq_show | |
965 | }; | |
966 | ||
967 | static int profile_open(struct inode *inode, struct file *file) | |
968 | { | |
969 | return seq_open(file, &profile_seq_op); | |
970 | } | |
971 | ||
972 | static const struct file_operations kprobe_profile_ops = { | |
973 | .owner = THIS_MODULE, | |
974 | .open = profile_open, | |
975 | .read = seq_read, | |
976 | .llseek = seq_lseek, | |
977 | .release = seq_release, | |
978 | }; | |
979 | ||
413d37d1 | 980 | /* Kprobe handler */ |
3da0f180 | 981 | static nokprobe_inline void |
c31ffb3f | 982 | __kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs, |
7f1d2f82 | 983 | struct trace_event_file *trace_file) |
413d37d1 | 984 | { |
93ccae7a | 985 | struct kprobe_trace_entry_head *entry; |
413d37d1 | 986 | struct ring_buffer_event *event; |
8f8ffe24 | 987 | struct ring_buffer *buffer; |
e09c8614 | 988 | int size, dsize, pc; |
413d37d1 | 989 | unsigned long irq_flags; |
2425bcb9 | 990 | struct trace_event_call *call = &tk->tp.call; |
413d37d1 | 991 | |
7f1d2f82 | 992 | WARN_ON(call != trace_file->event_call); |
41a7dd42 | 993 | |
09a5059a | 994 | if (trace_trigger_soft_disabled(trace_file)) |
13a1e4ae | 995 | return; |
b8820084 | 996 | |
413d37d1 MH |
997 | local_save_flags(irq_flags); |
998 | pc = preempt_count(); | |
999 | ||
c31ffb3f NK |
1000 | dsize = __get_data_size(&tk->tp, regs); |
1001 | size = sizeof(*entry) + tk->tp.size + dsize; | |
413d37d1 | 1002 | |
7f1d2f82 | 1003 | event = trace_event_buffer_lock_reserve(&buffer, trace_file, |
41a7dd42 MH |
1004 | call->event.type, |
1005 | size, irq_flags, pc); | |
413d37d1 | 1006 | if (!event) |
1e12a4a7 | 1007 | return; |
413d37d1 MH |
1008 | |
1009 | entry = ring_buffer_event_data(event); | |
c31ffb3f NK |
1010 | entry->ip = (unsigned long)tk->rp.kp.addr; |
1011 | store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); | |
413d37d1 | 1012 | |
7f1d2f82 | 1013 | event_trigger_unlock_commit_regs(trace_file, buffer, event, |
13a1e4ae | 1014 | entry, irq_flags, pc, regs); |
413d37d1 MH |
1015 | } |
1016 | ||
3da0f180 | 1017 | static void |
c31ffb3f | 1018 | kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs) |
41a7dd42 | 1019 | { |
b04d52e3 | 1020 | struct event_file_link *link; |
41a7dd42 | 1021 | |
c31ffb3f NK |
1022 | list_for_each_entry_rcu(link, &tk->tp.files, list) |
1023 | __kprobe_trace_func(tk, regs, link->file); | |
41a7dd42 | 1024 | } |
3da0f180 | 1025 | NOKPROBE_SYMBOL(kprobe_trace_func); |
41a7dd42 | 1026 | |
413d37d1 | 1027 | /* Kretprobe handler */ |
3da0f180 | 1028 | static nokprobe_inline void |
c31ffb3f | 1029 | __kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, |
41a7dd42 | 1030 | struct pt_regs *regs, |
7f1d2f82 | 1031 | struct trace_event_file *trace_file) |
413d37d1 | 1032 | { |
93ccae7a | 1033 | struct kretprobe_trace_entry_head *entry; |
413d37d1 | 1034 | struct ring_buffer_event *event; |
8f8ffe24 | 1035 | struct ring_buffer *buffer; |
e09c8614 | 1036 | int size, pc, dsize; |
413d37d1 | 1037 | unsigned long irq_flags; |
2425bcb9 | 1038 | struct trace_event_call *call = &tk->tp.call; |
413d37d1 | 1039 | |
7f1d2f82 | 1040 | WARN_ON(call != trace_file->event_call); |
41a7dd42 | 1041 | |
09a5059a | 1042 | if (trace_trigger_soft_disabled(trace_file)) |
13a1e4ae | 1043 | return; |
b8820084 | 1044 | |
413d37d1 MH |
1045 | local_save_flags(irq_flags); |
1046 | pc = preempt_count(); | |
1047 | ||
c31ffb3f NK |
1048 | dsize = __get_data_size(&tk->tp, regs); |
1049 | size = sizeof(*entry) + tk->tp.size + dsize; | |
413d37d1 | 1050 | |
7f1d2f82 | 1051 | event = trace_event_buffer_lock_reserve(&buffer, trace_file, |
41a7dd42 MH |
1052 | call->event.type, |
1053 | size, irq_flags, pc); | |
413d37d1 | 1054 | if (!event) |
1e12a4a7 | 1055 | return; |
413d37d1 MH |
1056 | |
1057 | entry = ring_buffer_event_data(event); | |
c31ffb3f | 1058 | entry->func = (unsigned long)tk->rp.kp.addr; |
413d37d1 | 1059 | entry->ret_ip = (unsigned long)ri->ret_addr; |
c31ffb3f | 1060 | store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); |
413d37d1 | 1061 | |
7f1d2f82 | 1062 | event_trigger_unlock_commit_regs(trace_file, buffer, event, |
13a1e4ae | 1063 | entry, irq_flags, pc, regs); |
413d37d1 MH |
1064 | } |
1065 | ||
3da0f180 | 1066 | static void |
c31ffb3f | 1067 | kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, |
41a7dd42 MH |
1068 | struct pt_regs *regs) |
1069 | { | |
b04d52e3 | 1070 | struct event_file_link *link; |
41a7dd42 | 1071 | |
c31ffb3f NK |
1072 | list_for_each_entry_rcu(link, &tk->tp.files, list) |
1073 | __kretprobe_trace_func(tk, ri, regs, link->file); | |
41a7dd42 | 1074 | } |
3da0f180 | 1075 | NOKPROBE_SYMBOL(kretprobe_trace_func); |
41a7dd42 | 1076 | |
413d37d1 | 1077 | /* Event entry printers */ |
b62fdd97 | 1078 | static enum print_line_t |
a9a57763 SR |
1079 | print_kprobe_event(struct trace_iterator *iter, int flags, |
1080 | struct trace_event *event) | |
413d37d1 | 1081 | { |
93ccae7a | 1082 | struct kprobe_trace_entry_head *field; |
413d37d1 | 1083 | struct trace_seq *s = &iter->seq; |
eca0d916 | 1084 | struct trace_probe *tp; |
93ccae7a | 1085 | u8 *data; |
413d37d1 MH |
1086 | int i; |
1087 | ||
93ccae7a | 1088 | field = (struct kprobe_trace_entry_head *)iter->ent; |
80decc70 | 1089 | tp = container_of(event, struct trace_probe, call.event); |
413d37d1 | 1090 | |
687fcc4a | 1091 | trace_seq_printf(s, "%s: (", trace_event_name(&tp->call)); |
6e9f23d1 | 1092 | |
413d37d1 | 1093 | if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET)) |
85224da0 | 1094 | goto out; |
413d37d1 | 1095 | |
85224da0 | 1096 | trace_seq_putc(s, ')'); |
413d37d1 | 1097 | |
93ccae7a MH |
1098 | data = (u8 *)&field[1]; |
1099 | for (i = 0; i < tp->nr_args; i++) | |
1100 | if (!tp->args[i].type->print(s, tp->args[i].name, | |
e09c8614 | 1101 | data + tp->args[i].offset, field)) |
85224da0 | 1102 | goto out; |
413d37d1 | 1103 | |
85224da0 SRRH |
1104 | trace_seq_putc(s, '\n'); |
1105 | out: | |
1106 | return trace_handle_return(s); | |
413d37d1 MH |
1107 | } |
1108 | ||
b62fdd97 | 1109 | static enum print_line_t |
a9a57763 SR |
1110 | print_kretprobe_event(struct trace_iterator *iter, int flags, |
1111 | struct trace_event *event) | |
413d37d1 | 1112 | { |
93ccae7a | 1113 | struct kretprobe_trace_entry_head *field; |
413d37d1 | 1114 | struct trace_seq *s = &iter->seq; |
eca0d916 | 1115 | struct trace_probe *tp; |
93ccae7a | 1116 | u8 *data; |
413d37d1 MH |
1117 | int i; |
1118 | ||
93ccae7a | 1119 | field = (struct kretprobe_trace_entry_head *)iter->ent; |
80decc70 | 1120 | tp = container_of(event, struct trace_probe, call.event); |
413d37d1 | 1121 | |
687fcc4a | 1122 | trace_seq_printf(s, "%s: (", trace_event_name(&tp->call)); |
6e9f23d1 | 1123 | |
413d37d1 | 1124 | if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET)) |
85224da0 | 1125 | goto out; |
413d37d1 | 1126 | |
85224da0 | 1127 | trace_seq_puts(s, " <- "); |
413d37d1 MH |
1128 | |
1129 | if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET)) | |
85224da0 | 1130 | goto out; |
413d37d1 | 1131 | |
85224da0 | 1132 | trace_seq_putc(s, ')'); |
413d37d1 | 1133 | |
93ccae7a MH |
1134 | data = (u8 *)&field[1]; |
1135 | for (i = 0; i < tp->nr_args; i++) | |
1136 | if (!tp->args[i].type->print(s, tp->args[i].name, | |
e09c8614 | 1137 | data + tp->args[i].offset, field)) |
85224da0 | 1138 | goto out; |
413d37d1 | 1139 | |
85224da0 | 1140 | trace_seq_putc(s, '\n'); |
413d37d1 | 1141 | |
85224da0 SRRH |
1142 | out: |
1143 | return trace_handle_return(s); | |
413d37d1 MH |
1144 | } |
1145 | ||
413d37d1 | 1146 | |
2425bcb9 | 1147 | static int kprobe_event_define_fields(struct trace_event_call *event_call) |
413d37d1 MH |
1148 | { |
1149 | int ret, i; | |
93ccae7a | 1150 | struct kprobe_trace_entry_head field; |
c31ffb3f | 1151 | struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data; |
413d37d1 | 1152 | |
a703d946 | 1153 | DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0); |
eca0d916 | 1154 | /* Set argument names as fields */ |
c31ffb3f NK |
1155 | for (i = 0; i < tk->tp.nr_args; i++) { |
1156 | struct probe_arg *parg = &tk->tp.args[i]; | |
1157 | ||
1158 | ret = trace_define_field(event_call, parg->type->fmttype, | |
1159 | parg->name, | |
1160 | sizeof(field) + parg->offset, | |
1161 | parg->type->size, | |
1162 | parg->type->is_signed, | |
93ccae7a MH |
1163 | FILTER_OTHER); |
1164 | if (ret) | |
1165 | return ret; | |
1166 | } | |
413d37d1 MH |
1167 | return 0; |
1168 | } | |
1169 | ||
2425bcb9 | 1170 | static int kretprobe_event_define_fields(struct trace_event_call *event_call) |
413d37d1 MH |
1171 | { |
1172 | int ret, i; | |
93ccae7a | 1173 | struct kretprobe_trace_entry_head field; |
c31ffb3f | 1174 | struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data; |
413d37d1 | 1175 | |
a703d946 MH |
1176 | DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0); |
1177 | DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0); | |
eca0d916 | 1178 | /* Set argument names as fields */ |
c31ffb3f NK |
1179 | for (i = 0; i < tk->tp.nr_args; i++) { |
1180 | struct probe_arg *parg = &tk->tp.args[i]; | |
1181 | ||
1182 | ret = trace_define_field(event_call, parg->type->fmttype, | |
1183 | parg->name, | |
1184 | sizeof(field) + parg->offset, | |
1185 | parg->type->size, | |
1186 | parg->type->is_signed, | |
93ccae7a MH |
1187 | FILTER_OTHER); |
1188 | if (ret) | |
1189 | return ret; | |
1190 | } | |
413d37d1 MH |
1191 | return 0; |
1192 | } | |
1193 | ||
07b139c8 | 1194 | #ifdef CONFIG_PERF_EVENTS |
e08d1c65 MH |
1195 | |
1196 | /* Kprobe profile handler */ | |
9802d865 | 1197 | static int |
c31ffb3f | 1198 | kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs) |
e08d1c65 | 1199 | { |
2425bcb9 | 1200 | struct trace_event_call *call = &tk->tp.call; |
93ccae7a | 1201 | struct kprobe_trace_entry_head *entry; |
1c024eca | 1202 | struct hlist_head *head; |
e09c8614 | 1203 | int size, __size, dsize; |
4ed7c92d | 1204 | int rctx; |
e08d1c65 | 1205 | |
9802d865 | 1206 | if (bpf_prog_array_valid(call)) { |
66665ad2 | 1207 | unsigned long orig_ip = instruction_pointer(regs); |
9802d865 JB |
1208 | int ret; |
1209 | ||
1210 | ret = trace_call_bpf(call, regs); | |
1211 | ||
1212 | /* | |
1213 | * We need to check and see if we modified the pc of the | |
1214 | * pt_regs, and if so clear the kprobe and return 1 so that we | |
66665ad2 MH |
1215 | * don't do the single stepping. |
1216 | * The ftrace kprobe handler leaves it up to us to re-enable | |
1217 | * preemption here before returning if we've modified the ip. | |
9802d865 | 1218 | */ |
66665ad2 | 1219 | if (orig_ip != instruction_pointer(regs)) { |
9802d865 | 1220 | reset_current_kprobe(); |
66665ad2 | 1221 | preempt_enable_no_resched(); |
9802d865 JB |
1222 | return 1; |
1223 | } | |
1224 | if (!ret) | |
1225 | return 0; | |
1226 | } | |
2541517c | 1227 | |
288e984e ON |
1228 | head = this_cpu_ptr(call->perf_events); |
1229 | if (hlist_empty(head)) | |
9802d865 | 1230 | return 0; |
288e984e | 1231 | |
c31ffb3f NK |
1232 | dsize = __get_data_size(&tk->tp, regs); |
1233 | __size = sizeof(*entry) + tk->tp.size + dsize; | |
74ebb63e MH |
1234 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
1235 | size -= sizeof(u32); | |
ce71b9df | 1236 | |
1e1dcd93 | 1237 | entry = perf_trace_buf_alloc(size, NULL, &rctx); |
430ad5a6 | 1238 | if (!entry) |
9802d865 | 1239 | return 0; |
a1a138d0 | 1240 | |
c31ffb3f | 1241 | entry->ip = (unsigned long)tk->rp.kp.addr; |
e09c8614 | 1242 | memset(&entry[1], 0, dsize); |
c31ffb3f | 1243 | store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); |
1e1dcd93 | 1244 | perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, |
8fd0fbbe | 1245 | head, NULL); |
9802d865 | 1246 | return 0; |
e08d1c65 | 1247 | } |
3da0f180 | 1248 | NOKPROBE_SYMBOL(kprobe_perf_func); |
e08d1c65 MH |
1249 | |
1250 | /* Kretprobe profile handler */ | |
3da0f180 | 1251 | static void |
c31ffb3f | 1252 | kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, |
2b106aab | 1253 | struct pt_regs *regs) |
e08d1c65 | 1254 | { |
2425bcb9 | 1255 | struct trace_event_call *call = &tk->tp.call; |
93ccae7a | 1256 | struct kretprobe_trace_entry_head *entry; |
1c024eca | 1257 | struct hlist_head *head; |
e09c8614 | 1258 | int size, __size, dsize; |
4ed7c92d | 1259 | int rctx; |
e08d1c65 | 1260 | |
e87c6bc3 | 1261 | if (bpf_prog_array_valid(call) && !trace_call_bpf(call, regs)) |
2541517c AS |
1262 | return; |
1263 | ||
288e984e ON |
1264 | head = this_cpu_ptr(call->perf_events); |
1265 | if (hlist_empty(head)) | |
1266 | return; | |
1267 | ||
c31ffb3f NK |
1268 | dsize = __get_data_size(&tk->tp, regs); |
1269 | __size = sizeof(*entry) + tk->tp.size + dsize; | |
74ebb63e MH |
1270 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
1271 | size -= sizeof(u32); | |
444a2a3b | 1272 | |
1e1dcd93 | 1273 | entry = perf_trace_buf_alloc(size, NULL, &rctx); |
430ad5a6 | 1274 | if (!entry) |
1e12a4a7 | 1275 | return; |
e08d1c65 | 1276 | |
c31ffb3f | 1277 | entry->func = (unsigned long)tk->rp.kp.addr; |
a1a138d0 | 1278 | entry->ret_ip = (unsigned long)ri->ret_addr; |
c31ffb3f | 1279 | store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); |
1e1dcd93 | 1280 | perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, |
8fd0fbbe | 1281 | head, NULL); |
e08d1c65 | 1282 | } |
3da0f180 | 1283 | NOKPROBE_SYMBOL(kretprobe_perf_func); |
07b139c8 | 1284 | #endif /* CONFIG_PERF_EVENTS */ |
50d78056 | 1285 | |
3fe3d619 ON |
1286 | /* |
1287 | * called by perf_trace_init() or __ftrace_set_clr_event() under event_mutex. | |
1288 | * | |
1289 | * kprobe_trace_self_tests_init() does enable_trace_probe/disable_trace_probe | |
1290 | * lockless, but we can't race with this __init function. | |
1291 | */ | |
2425bcb9 | 1292 | static int kprobe_register(struct trace_event_call *event, |
fbc1963d | 1293 | enum trace_reg type, void *data) |
2239291a | 1294 | { |
c31ffb3f | 1295 | struct trace_kprobe *tk = (struct trace_kprobe *)event->data; |
7f1d2f82 | 1296 | struct trace_event_file *file = data; |
1538f888 | 1297 | |
2239291a SR |
1298 | switch (type) { |
1299 | case TRACE_REG_REGISTER: | |
c31ffb3f | 1300 | return enable_trace_kprobe(tk, file); |
2239291a | 1301 | case TRACE_REG_UNREGISTER: |
c31ffb3f | 1302 | return disable_trace_kprobe(tk, file); |
2239291a SR |
1303 | |
1304 | #ifdef CONFIG_PERF_EVENTS | |
1305 | case TRACE_REG_PERF_REGISTER: | |
c31ffb3f | 1306 | return enable_trace_kprobe(tk, NULL); |
2239291a | 1307 | case TRACE_REG_PERF_UNREGISTER: |
c31ffb3f | 1308 | return disable_trace_kprobe(tk, NULL); |
ceec0b6f JO |
1309 | case TRACE_REG_PERF_OPEN: |
1310 | case TRACE_REG_PERF_CLOSE: | |
489c75c3 JO |
1311 | case TRACE_REG_PERF_ADD: |
1312 | case TRACE_REG_PERF_DEL: | |
ceec0b6f | 1313 | return 0; |
2239291a SR |
1314 | #endif |
1315 | } | |
1316 | return 0; | |
1317 | } | |
50d78056 | 1318 | |
3da0f180 | 1319 | static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) |
50d78056 | 1320 | { |
c31ffb3f | 1321 | struct trace_kprobe *tk = container_of(kp, struct trace_kprobe, rp.kp); |
9802d865 | 1322 | int ret = 0; |
e08d1c65 | 1323 | |
a7636d9e | 1324 | raw_cpu_inc(*tk->nhit); |
48182bd2 | 1325 | |
c31ffb3f NK |
1326 | if (tk->tp.flags & TP_FLAG_TRACE) |
1327 | kprobe_trace_func(tk, regs); | |
07b139c8 | 1328 | #ifdef CONFIG_PERF_EVENTS |
66665ad2 | 1329 | if (tk->tp.flags & TP_FLAG_PROFILE) |
9802d865 | 1330 | ret = kprobe_perf_func(tk, regs); |
07b139c8 | 1331 | #endif |
9802d865 | 1332 | return ret; |
50d78056 | 1333 | } |
3da0f180 | 1334 | NOKPROBE_SYMBOL(kprobe_dispatcher); |
50d78056 | 1335 | |
3da0f180 MH |
1336 | static int |
1337 | kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs) | |
50d78056 | 1338 | { |
c31ffb3f | 1339 | struct trace_kprobe *tk = container_of(ri->rp, struct trace_kprobe, rp); |
50d78056 | 1340 | |
a7636d9e | 1341 | raw_cpu_inc(*tk->nhit); |
48182bd2 | 1342 | |
c31ffb3f NK |
1343 | if (tk->tp.flags & TP_FLAG_TRACE) |
1344 | kretprobe_trace_func(tk, ri, regs); | |
07b139c8 | 1345 | #ifdef CONFIG_PERF_EVENTS |
c31ffb3f NK |
1346 | if (tk->tp.flags & TP_FLAG_PROFILE) |
1347 | kretprobe_perf_func(tk, ri, regs); | |
07b139c8 | 1348 | #endif |
50d78056 MH |
1349 | return 0; /* We don't tweek kernel, so just return 0 */ |
1350 | } | |
3da0f180 | 1351 | NOKPROBE_SYMBOL(kretprobe_dispatcher); |
e08d1c65 | 1352 | |
a9a57763 SR |
1353 | static struct trace_event_functions kretprobe_funcs = { |
1354 | .trace = print_kretprobe_event | |
1355 | }; | |
1356 | ||
1357 | static struct trace_event_functions kprobe_funcs = { | |
1358 | .trace = print_kprobe_event | |
1359 | }; | |
1360 | ||
c31ffb3f | 1361 | static int register_kprobe_event(struct trace_kprobe *tk) |
413d37d1 | 1362 | { |
2425bcb9 | 1363 | struct trace_event_call *call = &tk->tp.call; |
413d37d1 MH |
1364 | int ret; |
1365 | ||
2425bcb9 | 1366 | /* Initialize trace_event_call */ |
ffb9f995 | 1367 | INIT_LIST_HEAD(&call->class->fields); |
c31ffb3f | 1368 | if (trace_kprobe_is_return(tk)) { |
80decc70 | 1369 | call->event.funcs = &kretprobe_funcs; |
2e33af02 | 1370 | call->class->define_fields = kretprobe_event_define_fields; |
413d37d1 | 1371 | } else { |
80decc70 | 1372 | call->event.funcs = &kprobe_funcs; |
2e33af02 | 1373 | call->class->define_fields = kprobe_event_define_fields; |
413d37d1 | 1374 | } |
5bf652aa | 1375 | if (set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0) |
a342a028 | 1376 | return -ENOMEM; |
9023c930 | 1377 | ret = register_trace_event(&call->event); |
32c0edae | 1378 | if (!ret) { |
a342a028 | 1379 | kfree(call->print_fmt); |
ff50d991 | 1380 | return -ENODEV; |
a342a028 | 1381 | } |
72cbbc89 | 1382 | call->flags = TRACE_EVENT_FL_KPROBE; |
2239291a | 1383 | call->class->reg = kprobe_register; |
c31ffb3f | 1384 | call->data = tk; |
413d37d1 | 1385 | ret = trace_add_event_call(call); |
ff50d991 | 1386 | if (ret) { |
de7b2973 | 1387 | pr_info("Failed to register kprobe event: %s\n", |
687fcc4a | 1388 | trace_event_name(call)); |
a342a028 | 1389 | kfree(call->print_fmt); |
9023c930 | 1390 | unregister_trace_event(&call->event); |
ff50d991 | 1391 | } |
413d37d1 MH |
1392 | return ret; |
1393 | } | |
1394 | ||
c31ffb3f | 1395 | static int unregister_kprobe_event(struct trace_kprobe *tk) |
413d37d1 | 1396 | { |
40c32592 SRRH |
1397 | int ret; |
1398 | ||
ff50d991 | 1399 | /* tp->event is unregistered in trace_remove_event_call() */ |
c31ffb3f | 1400 | ret = trace_remove_event_call(&tk->tp.call); |
40c32592 | 1401 | if (!ret) |
c31ffb3f | 1402 | kfree(tk->tp.call.print_fmt); |
40c32592 | 1403 | return ret; |
413d37d1 MH |
1404 | } |
1405 | ||
8434dc93 | 1406 | /* Make a tracefs interface for controlling probe points */ |
413d37d1 MH |
1407 | static __init int init_kprobe_trace(void) |
1408 | { | |
1409 | struct dentry *d_tracer; | |
1410 | struct dentry *entry; | |
413d37d1 | 1411 | |
c31ffb3f | 1412 | if (register_module_notifier(&trace_kprobe_module_nb)) |
61424318 MH |
1413 | return -EINVAL; |
1414 | ||
413d37d1 | 1415 | d_tracer = tracing_init_dentry(); |
14a5ae40 | 1416 | if (IS_ERR(d_tracer)) |
413d37d1 MH |
1417 | return 0; |
1418 | ||
8434dc93 | 1419 | entry = tracefs_create_file("kprobe_events", 0644, d_tracer, |
413d37d1 MH |
1420 | NULL, &kprobe_events_ops); |
1421 | ||
cd7e7bd5 | 1422 | /* Event list interface */ |
413d37d1 | 1423 | if (!entry) |
a395d6a7 | 1424 | pr_warn("Could not create tracefs 'kprobe_events' entry\n"); |
cd7e7bd5 MH |
1425 | |
1426 | /* Profile interface */ | |
8434dc93 | 1427 | entry = tracefs_create_file("kprobe_profile", 0444, d_tracer, |
cd7e7bd5 MH |
1428 | NULL, &kprobe_profile_ops); |
1429 | ||
1430 | if (!entry) | |
a395d6a7 | 1431 | pr_warn("Could not create tracefs 'kprobe_profile' entry\n"); |
413d37d1 MH |
1432 | return 0; |
1433 | } | |
1434 | fs_initcall(init_kprobe_trace); | |
1435 | ||
1436 | ||
1437 | #ifdef CONFIG_FTRACE_STARTUP_TEST | |
265a5b7e SR |
1438 | /* |
1439 | * The "__used" keeps gcc from removing the function symbol | |
d4d7ccc8 MN |
1440 | * from the kallsyms table. 'noinline' makes sure that there |
1441 | * isn't an inlined version used by the test method below | |
265a5b7e | 1442 | */ |
d4d7ccc8 MN |
1443 | static __used __init noinline int |
1444 | kprobe_trace_selftest_target(int a1, int a2, int a3, int a4, int a5, int a6) | |
413d37d1 MH |
1445 | { |
1446 | return a1 + a2 + a3 + a4 + a5 + a6; | |
1447 | } | |
1448 | ||
26a346f2 | 1449 | static __init struct trace_event_file * |
c31ffb3f | 1450 | find_trace_probe_file(struct trace_kprobe *tk, struct trace_array *tr) |
41a7dd42 | 1451 | { |
7f1d2f82 | 1452 | struct trace_event_file *file; |
41a7dd42 MH |
1453 | |
1454 | list_for_each_entry(file, &tr->events, list) | |
c31ffb3f | 1455 | if (file->event_call == &tk->tp.call) |
41a7dd42 MH |
1456 | return file; |
1457 | ||
1458 | return NULL; | |
1459 | } | |
1460 | ||
3fe3d619 | 1461 | /* |
c31ffb3f | 1462 | * Nobody but us can call enable_trace_kprobe/disable_trace_kprobe at this |
3fe3d619 ON |
1463 | * stage, we can do this lockless. |
1464 | */ | |
413d37d1 MH |
1465 | static __init int kprobe_trace_self_tests_init(void) |
1466 | { | |
231e36f4 | 1467 | int ret, warn = 0; |
413d37d1 | 1468 | int (*target)(int, int, int, int, int, int); |
c31ffb3f | 1469 | struct trace_kprobe *tk; |
7f1d2f82 | 1470 | struct trace_event_file *file; |
413d37d1 | 1471 | |
748ec3a2 YY |
1472 | if (tracing_is_disabled()) |
1473 | return -ENODEV; | |
1474 | ||
413d37d1 MH |
1475 | target = kprobe_trace_selftest_target; |
1476 | ||
1477 | pr_info("Testing kprobe tracing: "); | |
1478 | ||
7e465baa TZ |
1479 | ret = trace_run_command("p:testprobe kprobe_trace_selftest_target " |
1480 | "$stack $stack0 +0($stack)", | |
1481 | create_trace_kprobe); | |
231e36f4 | 1482 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 1483 | pr_warn("error on probing function entry.\n"); |
231e36f4 MH |
1484 | warn++; |
1485 | } else { | |
1486 | /* Enable trace point */ | |
c31ffb3f NK |
1487 | tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); |
1488 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 1489 | pr_warn("error on getting new probe.\n"); |
231e36f4 | 1490 | warn++; |
41a7dd42 | 1491 | } else { |
c31ffb3f | 1492 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
1493 | if (WARN_ON_ONCE(file == NULL)) { |
1494 | pr_warn("error on getting probe file.\n"); | |
1495 | warn++; | |
1496 | } else | |
c31ffb3f | 1497 | enable_trace_kprobe(tk, file); |
41a7dd42 | 1498 | } |
231e36f4 | 1499 | } |
413d37d1 | 1500 | |
7e465baa TZ |
1501 | ret = trace_run_command("r:testprobe2 kprobe_trace_selftest_target " |
1502 | "$retval", create_trace_kprobe); | |
231e36f4 | 1503 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 1504 | pr_warn("error on probing function return.\n"); |
231e36f4 MH |
1505 | warn++; |
1506 | } else { | |
1507 | /* Enable trace point */ | |
c31ffb3f NK |
1508 | tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); |
1509 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 1510 | pr_warn("error on getting 2nd new probe.\n"); |
231e36f4 | 1511 | warn++; |
41a7dd42 | 1512 | } else { |
c31ffb3f | 1513 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
1514 | if (WARN_ON_ONCE(file == NULL)) { |
1515 | pr_warn("error on getting probe file.\n"); | |
1516 | warn++; | |
1517 | } else | |
c31ffb3f | 1518 | enable_trace_kprobe(tk, file); |
41a7dd42 | 1519 | } |
231e36f4 MH |
1520 | } |
1521 | ||
1522 | if (warn) | |
1523 | goto end; | |
413d37d1 MH |
1524 | |
1525 | ret = target(1, 2, 3, 4, 5, 6); | |
1526 | ||
d4d7ccc8 MN |
1527 | /* |
1528 | * Not expecting an error here, the check is only to prevent the | |
1529 | * optimizer from removing the call to target() as otherwise there | |
1530 | * are no side-effects and the call is never performed. | |
1531 | */ | |
1532 | if (ret != 21) | |
1533 | warn++; | |
1534 | ||
02ca1521 | 1535 | /* Disable trace points before removing it */ |
c31ffb3f NK |
1536 | tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); |
1537 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 1538 | pr_warn("error on getting test probe.\n"); |
02ca1521 | 1539 | warn++; |
41a7dd42 | 1540 | } else { |
d4d7ccc8 MN |
1541 | if (trace_kprobe_nhit(tk) != 1) { |
1542 | pr_warn("incorrect number of testprobe hits\n"); | |
1543 | warn++; | |
1544 | } | |
1545 | ||
c31ffb3f | 1546 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
1547 | if (WARN_ON_ONCE(file == NULL)) { |
1548 | pr_warn("error on getting probe file.\n"); | |
1549 | warn++; | |
1550 | } else | |
c31ffb3f | 1551 | disable_trace_kprobe(tk, file); |
41a7dd42 | 1552 | } |
02ca1521 | 1553 | |
c31ffb3f NK |
1554 | tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); |
1555 | if (WARN_ON_ONCE(tk == NULL)) { | |
41a7dd42 | 1556 | pr_warn("error on getting 2nd test probe.\n"); |
02ca1521 | 1557 | warn++; |
41a7dd42 | 1558 | } else { |
d4d7ccc8 MN |
1559 | if (trace_kprobe_nhit(tk) != 1) { |
1560 | pr_warn("incorrect number of testprobe2 hits\n"); | |
1561 | warn++; | |
1562 | } | |
1563 | ||
c31ffb3f | 1564 | file = find_trace_probe_file(tk, top_trace_array()); |
41a7dd42 MH |
1565 | if (WARN_ON_ONCE(file == NULL)) { |
1566 | pr_warn("error on getting probe file.\n"); | |
1567 | warn++; | |
1568 | } else | |
c31ffb3f | 1569 | disable_trace_kprobe(tk, file); |
41a7dd42 | 1570 | } |
02ca1521 | 1571 | |
7e465baa | 1572 | ret = trace_run_command("-:testprobe", create_trace_kprobe); |
231e36f4 | 1573 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 1574 | pr_warn("error on deleting a probe.\n"); |
231e36f4 MH |
1575 | warn++; |
1576 | } | |
1577 | ||
7e465baa | 1578 | ret = trace_run_command("-:testprobe2", create_trace_kprobe); |
231e36f4 | 1579 | if (WARN_ON_ONCE(ret)) { |
41a7dd42 | 1580 | pr_warn("error on deleting a probe.\n"); |
231e36f4 MH |
1581 | warn++; |
1582 | } | |
413d37d1 | 1583 | |
231e36f4 | 1584 | end: |
c31ffb3f | 1585 | release_all_trace_kprobes(); |
30e7d894 TG |
1586 | /* |
1587 | * Wait for the optimizer work to finish. Otherwise it might fiddle | |
1588 | * with probes in already freed __init text. | |
1589 | */ | |
1590 | wait_for_kprobe_optimizer(); | |
231e36f4 MH |
1591 | if (warn) |
1592 | pr_cont("NG: Some tests are failed. Please check them.\n"); | |
1593 | else | |
1594 | pr_cont("OK\n"); | |
413d37d1 MH |
1595 | return 0; |
1596 | } | |
1597 | ||
1598 | late_initcall(kprobe_trace_self_tests_init); | |
1599 | ||
1600 | #endif |