Commit | Line | Data |
---|---|---|
47788c58 | 1 | #include <trace/syscall.h> |
1c569f02 | 2 | #include <trace/events/syscalls.h> |
5a0e3ad6 | 3 | #include <linux/slab.h> |
ee08c6ec | 4 | #include <linux/kernel.h> |
fb34a08c | 5 | #include <linux/ftrace.h> |
cdd6c482 | 6 | #include <linux/perf_event.h> |
ee08c6ec FW |
7 | #include <asm/syscall.h> |
8 | ||
9 | #include "trace_output.h" | |
10 | #include "trace.h" | |
11 | ||
5be71b61 | 12 | static DEFINE_MUTEX(syscall_trace_lock); |
fb34a08c JB |
13 | static int sys_refcount_enter; |
14 | static int sys_refcount_exit; | |
57421dbb JB |
15 | static DECLARE_BITMAP(enabled_enter_syscalls, NR_syscalls); |
16 | static DECLARE_BITMAP(enabled_exit_syscalls, NR_syscalls); | |
ee08c6ec | 17 | |
2239291a SR |
18 | static int syscall_enter_register(struct ftrace_event_call *event, |
19 | enum trace_reg type); | |
20 | static int syscall_exit_register(struct ftrace_event_call *event, | |
21 | enum trace_reg type); | |
22 | ||
2e33af02 SR |
23 | static int syscall_enter_define_fields(struct ftrace_event_call *call); |
24 | static int syscall_exit_define_fields(struct ftrace_event_call *call); | |
25 | ||
26 | static struct list_head * | |
27 | syscall_get_enter_fields(struct ftrace_event_call *call) | |
28 | { | |
29 | struct syscall_metadata *entry = call->data; | |
30 | ||
31 | return &entry->enter_fields; | |
32 | } | |
33 | ||
80decc70 | 34 | struct trace_event_functions enter_syscall_print_funcs = { |
7f85803a | 35 | .trace = print_syscall_enter, |
80decc70 SR |
36 | }; |
37 | ||
38 | struct trace_event_functions exit_syscall_print_funcs = { | |
7f85803a | 39 | .trace = print_syscall_exit, |
80decc70 SR |
40 | }; |
41 | ||
2239291a | 42 | struct ftrace_event_class event_class_syscall_enter = { |
7f85803a LJ |
43 | .system = "syscalls", |
44 | .reg = syscall_enter_register, | |
45 | .define_fields = syscall_enter_define_fields, | |
46 | .get_fields = syscall_get_enter_fields, | |
47 | .raw_init = init_syscall_trace, | |
2239291a SR |
48 | }; |
49 | ||
50 | struct ftrace_event_class event_class_syscall_exit = { | |
7f85803a LJ |
51 | .system = "syscalls", |
52 | .reg = syscall_exit_register, | |
53 | .define_fields = syscall_exit_define_fields, | |
54 | .fields = LIST_HEAD_INIT(event_class_syscall_exit.fields), | |
55 | .raw_init = init_syscall_trace, | |
8f082018 SR |
56 | }; |
57 | ||
3d56e331 SR |
58 | extern struct syscall_metadata *__start_syscalls_metadata[]; |
59 | extern struct syscall_metadata *__stop_syscalls_metadata[]; | |
c44fc770 FW |
60 | |
61 | static struct syscall_metadata **syscalls_metadata; | |
62 | ||
b2d55496 IM |
63 | #ifndef ARCH_HAS_SYSCALL_MATCH_SYM_NAME |
64 | static inline bool arch_syscall_match_sym_name(const char *sym, const char *name) | |
65 | { | |
66 | /* | |
67 | * Only compare after the "sys" prefix. Archs that use | |
68 | * syscall wrappers may have syscalls symbols aliases prefixed | |
69 | * with "SyS" instead of "sys", leading to an unwanted | |
70 | * mismatch. | |
71 | */ | |
72 | return !strcmp(sym + 3, name + 3); | |
73 | } | |
74 | #endif | |
75 | ||
3d56e331 SR |
76 | static __init struct syscall_metadata * |
77 | find_syscall_meta(unsigned long syscall) | |
c44fc770 | 78 | { |
3d56e331 SR |
79 | struct syscall_metadata **start; |
80 | struct syscall_metadata **stop; | |
c44fc770 FW |
81 | char str[KSYM_SYMBOL_LEN]; |
82 | ||
83 | ||
3d56e331 SR |
84 | start = __start_syscalls_metadata; |
85 | stop = __stop_syscalls_metadata; | |
c44fc770 FW |
86 | kallsyms_lookup(syscall, NULL, NULL, NULL, str); |
87 | ||
88 | for ( ; start < stop; start++) { | |
b2d55496 | 89 | if ((*start)->name && arch_syscall_match_sym_name(str, (*start)->name)) |
3d56e331 | 90 | return *start; |
c44fc770 FW |
91 | } |
92 | return NULL; | |
93 | } | |
94 | ||
95 | static struct syscall_metadata *syscall_nr_to_meta(int nr) | |
96 | { | |
97 | if (!syscalls_metadata || nr >= NR_syscalls || nr < 0) | |
98 | return NULL; | |
99 | ||
100 | return syscalls_metadata[nr]; | |
101 | } | |
102 | ||
bed1ffca | 103 | enum print_line_t |
a9a57763 SR |
104 | print_syscall_enter(struct trace_iterator *iter, int flags, |
105 | struct trace_event *event) | |
bed1ffca FW |
106 | { |
107 | struct trace_seq *s = &iter->seq; | |
108 | struct trace_entry *ent = iter->ent; | |
109 | struct syscall_trace_enter *trace; | |
110 | struct syscall_metadata *entry; | |
111 | int i, ret, syscall; | |
112 | ||
64c12e04 | 113 | trace = (typeof(trace))ent; |
bed1ffca | 114 | syscall = trace->nr; |
bed1ffca | 115 | entry = syscall_nr_to_meta(syscall); |
64c12e04 | 116 | |
bed1ffca FW |
117 | if (!entry) |
118 | goto end; | |
119 | ||
32c0edae | 120 | if (entry->enter_event->event.type != ent->type) { |
64c12e04 JB |
121 | WARN_ON_ONCE(1); |
122 | goto end; | |
123 | } | |
124 | ||
bed1ffca FW |
125 | ret = trace_seq_printf(s, "%s(", entry->name); |
126 | if (!ret) | |
127 | return TRACE_TYPE_PARTIAL_LINE; | |
128 | ||
129 | for (i = 0; i < entry->nb_args; i++) { | |
130 | /* parameter types */ | |
ba8b3a40 | 131 | if (trace_flags & TRACE_ITER_VERBOSE) { |
bed1ffca FW |
132 | ret = trace_seq_printf(s, "%s ", entry->types[i]); |
133 | if (!ret) | |
134 | return TRACE_TYPE_PARTIAL_LINE; | |
135 | } | |
136 | /* parameter values */ | |
4539f077 | 137 | ret = trace_seq_printf(s, "%s: %lx%s", entry->args[i], |
bed1ffca | 138 | trace->args[i], |
4539f077 | 139 | i == entry->nb_args - 1 ? "" : ", "); |
bed1ffca FW |
140 | if (!ret) |
141 | return TRACE_TYPE_PARTIAL_LINE; | |
142 | } | |
143 | ||
4539f077 LZ |
144 | ret = trace_seq_putc(s, ')'); |
145 | if (!ret) | |
146 | return TRACE_TYPE_PARTIAL_LINE; | |
147 | ||
bed1ffca | 148 | end: |
4539f077 LZ |
149 | ret = trace_seq_putc(s, '\n'); |
150 | if (!ret) | |
151 | return TRACE_TYPE_PARTIAL_LINE; | |
152 | ||
bed1ffca FW |
153 | return TRACE_TYPE_HANDLED; |
154 | } | |
155 | ||
156 | enum print_line_t | |
a9a57763 SR |
157 | print_syscall_exit(struct trace_iterator *iter, int flags, |
158 | struct trace_event *event) | |
bed1ffca FW |
159 | { |
160 | struct trace_seq *s = &iter->seq; | |
161 | struct trace_entry *ent = iter->ent; | |
162 | struct syscall_trace_exit *trace; | |
163 | int syscall; | |
164 | struct syscall_metadata *entry; | |
165 | int ret; | |
166 | ||
64c12e04 | 167 | trace = (typeof(trace))ent; |
bed1ffca | 168 | syscall = trace->nr; |
bed1ffca | 169 | entry = syscall_nr_to_meta(syscall); |
64c12e04 | 170 | |
bed1ffca FW |
171 | if (!entry) { |
172 | trace_seq_printf(s, "\n"); | |
173 | return TRACE_TYPE_HANDLED; | |
174 | } | |
175 | ||
32c0edae | 176 | if (entry->exit_event->event.type != ent->type) { |
64c12e04 JB |
177 | WARN_ON_ONCE(1); |
178 | return TRACE_TYPE_UNHANDLED; | |
179 | } | |
180 | ||
bed1ffca FW |
181 | ret = trace_seq_printf(s, "%s -> 0x%lx\n", entry->name, |
182 | trace->ret); | |
183 | if (!ret) | |
184 | return TRACE_TYPE_PARTIAL_LINE; | |
185 | ||
186 | return TRACE_TYPE_HANDLED; | |
187 | } | |
188 | ||
e6971969 LZ |
189 | extern char *__bad_type_size(void); |
190 | ||
191 | #define SYSCALL_FIELD(type, name) \ | |
192 | sizeof(type) != sizeof(trace.name) ? \ | |
193 | __bad_type_size() : \ | |
26a50744 TZ |
194 | #type, #name, offsetof(typeof(trace), name), \ |
195 | sizeof(trace.name), is_signed_type(type) | |
e6971969 | 196 | |
50307a45 LJ |
197 | static |
198 | int __set_enter_print_fmt(struct syscall_metadata *entry, char *buf, int len) | |
199 | { | |
200 | int i; | |
201 | int pos = 0; | |
202 | ||
203 | /* When len=0, we just calculate the needed length */ | |
204 | #define LEN_OR_ZERO (len ? len - pos : 0) | |
205 | ||
206 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); | |
207 | for (i = 0; i < entry->nb_args; i++) { | |
208 | pos += snprintf(buf + pos, LEN_OR_ZERO, "%s: 0x%%0%zulx%s", | |
209 | entry->args[i], sizeof(unsigned long), | |
210 | i == entry->nb_args - 1 ? "" : ", "); | |
211 | } | |
212 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); | |
213 | ||
214 | for (i = 0; i < entry->nb_args; i++) { | |
215 | pos += snprintf(buf + pos, LEN_OR_ZERO, | |
216 | ", ((unsigned long)(REC->%s))", entry->args[i]); | |
217 | } | |
218 | ||
219 | #undef LEN_OR_ZERO | |
220 | ||
221 | /* return the length of print_fmt */ | |
222 | return pos; | |
223 | } | |
224 | ||
225 | static int set_syscall_print_fmt(struct ftrace_event_call *call) | |
226 | { | |
227 | char *print_fmt; | |
228 | int len; | |
229 | struct syscall_metadata *entry = call->data; | |
230 | ||
231 | if (entry->enter_event != call) { | |
232 | call->print_fmt = "\"0x%lx\", REC->ret"; | |
233 | return 0; | |
234 | } | |
235 | ||
236 | /* First: called with 0 length to calculate the needed length */ | |
237 | len = __set_enter_print_fmt(entry, NULL, 0); | |
238 | ||
239 | print_fmt = kmalloc(len + 1, GFP_KERNEL); | |
240 | if (!print_fmt) | |
241 | return -ENOMEM; | |
242 | ||
243 | /* Second: actually write the @print_fmt */ | |
244 | __set_enter_print_fmt(entry, print_fmt, len + 1); | |
245 | call->print_fmt = print_fmt; | |
246 | ||
247 | return 0; | |
248 | } | |
249 | ||
250 | static void free_syscall_print_fmt(struct ftrace_event_call *call) | |
251 | { | |
252 | struct syscall_metadata *entry = call->data; | |
253 | ||
254 | if (entry->enter_event == call) | |
255 | kfree(call->print_fmt); | |
256 | } | |
257 | ||
2e33af02 | 258 | static int syscall_enter_define_fields(struct ftrace_event_call *call) |
540b7b8d LZ |
259 | { |
260 | struct syscall_trace_enter trace; | |
31c16b13 | 261 | struct syscall_metadata *meta = call->data; |
540b7b8d | 262 | int ret; |
540b7b8d LZ |
263 | int i; |
264 | int offset = offsetof(typeof(trace), args); | |
265 | ||
0f1ef51d LJ |
266 | ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER); |
267 | if (ret) | |
268 | return ret; | |
269 | ||
540b7b8d | 270 | for (i = 0; i < meta->nb_args; i++) { |
aeaeae11 FW |
271 | ret = trace_define_field(call, meta->types[i], |
272 | meta->args[i], offset, | |
43b51ead LZ |
273 | sizeof(unsigned long), 0, |
274 | FILTER_OTHER); | |
540b7b8d LZ |
275 | offset += sizeof(unsigned long); |
276 | } | |
277 | ||
278 | return ret; | |
279 | } | |
280 | ||
2e33af02 | 281 | static int syscall_exit_define_fields(struct ftrace_event_call *call) |
540b7b8d LZ |
282 | { |
283 | struct syscall_trace_exit trace; | |
284 | int ret; | |
285 | ||
0f1ef51d LJ |
286 | ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER); |
287 | if (ret) | |
288 | return ret; | |
289 | ||
26a50744 | 290 | ret = trace_define_field(call, SYSCALL_FIELD(long, ret), |
43b51ead | 291 | FILTER_OTHER); |
540b7b8d LZ |
292 | |
293 | return ret; | |
294 | } | |
295 | ||
38516ab5 | 296 | void ftrace_syscall_enter(void *ignore, struct pt_regs *regs, long id) |
ee08c6ec | 297 | { |
bed1ffca FW |
298 | struct syscall_trace_enter *entry; |
299 | struct syscall_metadata *sys_data; | |
300 | struct ring_buffer_event *event; | |
e77405ad | 301 | struct ring_buffer *buffer; |
bed1ffca | 302 | int size; |
ee08c6ec FW |
303 | int syscall_nr; |
304 | ||
305 | syscall_nr = syscall_get_nr(current, regs); | |
cd0980fc HB |
306 | if (syscall_nr < 0) |
307 | return; | |
fb34a08c JB |
308 | if (!test_bit(syscall_nr, enabled_enter_syscalls)) |
309 | return; | |
ee08c6ec | 310 | |
bed1ffca FW |
311 | sys_data = syscall_nr_to_meta(syscall_nr); |
312 | if (!sys_data) | |
313 | return; | |
314 | ||
315 | size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args; | |
316 | ||
fcc19438 | 317 | event = trace_current_buffer_lock_reserve(&buffer, |
32c0edae | 318 | sys_data->enter_event->event.type, size, 0, 0); |
bed1ffca FW |
319 | if (!event) |
320 | return; | |
321 | ||
322 | entry = ring_buffer_event_data(event); | |
323 | entry->nr = syscall_nr; | |
324 | syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args); | |
325 | ||
e77405ad SR |
326 | if (!filter_current_check_discard(buffer, sys_data->enter_event, |
327 | entry, event)) | |
328 | trace_current_buffer_unlock_commit(buffer, event, 0, 0); | |
ee08c6ec FW |
329 | } |
330 | ||
38516ab5 | 331 | void ftrace_syscall_exit(void *ignore, struct pt_regs *regs, long ret) |
ee08c6ec | 332 | { |
bed1ffca FW |
333 | struct syscall_trace_exit *entry; |
334 | struct syscall_metadata *sys_data; | |
335 | struct ring_buffer_event *event; | |
e77405ad | 336 | struct ring_buffer *buffer; |
ee08c6ec FW |
337 | int syscall_nr; |
338 | ||
339 | syscall_nr = syscall_get_nr(current, regs); | |
cd0980fc HB |
340 | if (syscall_nr < 0) |
341 | return; | |
fb34a08c JB |
342 | if (!test_bit(syscall_nr, enabled_exit_syscalls)) |
343 | return; | |
ee08c6ec | 344 | |
bed1ffca FW |
345 | sys_data = syscall_nr_to_meta(syscall_nr); |
346 | if (!sys_data) | |
347 | return; | |
348 | ||
fcc19438 | 349 | event = trace_current_buffer_lock_reserve(&buffer, |
32c0edae | 350 | sys_data->exit_event->event.type, sizeof(*entry), 0, 0); |
bed1ffca FW |
351 | if (!event) |
352 | return; | |
353 | ||
354 | entry = ring_buffer_event_data(event); | |
355 | entry->nr = syscall_nr; | |
356 | entry->ret = syscall_get_return_value(current, regs); | |
357 | ||
e77405ad SR |
358 | if (!filter_current_check_discard(buffer, sys_data->exit_event, |
359 | entry, event)) | |
360 | trace_current_buffer_unlock_commit(buffer, event, 0, 0); | |
ee08c6ec FW |
361 | } |
362 | ||
bd1a5c84 | 363 | int reg_event_syscall_enter(struct ftrace_event_call *call) |
ee08c6ec | 364 | { |
fb34a08c JB |
365 | int ret = 0; |
366 | int num; | |
fb34a08c | 367 | |
c252f657 | 368 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 369 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
370 | return -ENOSYS; |
371 | mutex_lock(&syscall_trace_lock); | |
372 | if (!sys_refcount_enter) | |
38516ab5 | 373 | ret = register_trace_sys_enter(ftrace_syscall_enter, NULL); |
3b8e4273 | 374 | if (!ret) { |
fb34a08c JB |
375 | set_bit(num, enabled_enter_syscalls); |
376 | sys_refcount_enter++; | |
377 | } | |
378 | mutex_unlock(&syscall_trace_lock); | |
379 | return ret; | |
ee08c6ec FW |
380 | } |
381 | ||
bd1a5c84 | 382 | void unreg_event_syscall_enter(struct ftrace_event_call *call) |
ee08c6ec | 383 | { |
fb34a08c | 384 | int num; |
ee08c6ec | 385 | |
c252f657 | 386 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 387 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
388 | return; |
389 | mutex_lock(&syscall_trace_lock); | |
390 | sys_refcount_enter--; | |
391 | clear_bit(num, enabled_enter_syscalls); | |
392 | if (!sys_refcount_enter) | |
38516ab5 | 393 | unregister_trace_sys_enter(ftrace_syscall_enter, NULL); |
fb34a08c JB |
394 | mutex_unlock(&syscall_trace_lock); |
395 | } | |
ee08c6ec | 396 | |
bd1a5c84 | 397 | int reg_event_syscall_exit(struct ftrace_event_call *call) |
ee08c6ec | 398 | { |
fb34a08c JB |
399 | int ret = 0; |
400 | int num; | |
fb34a08c | 401 | |
c252f657 | 402 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 403 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
404 | return -ENOSYS; |
405 | mutex_lock(&syscall_trace_lock); | |
406 | if (!sys_refcount_exit) | |
38516ab5 | 407 | ret = register_trace_sys_exit(ftrace_syscall_exit, NULL); |
3b8e4273 | 408 | if (!ret) { |
fb34a08c JB |
409 | set_bit(num, enabled_exit_syscalls); |
410 | sys_refcount_exit++; | |
ee08c6ec | 411 | } |
fb34a08c JB |
412 | mutex_unlock(&syscall_trace_lock); |
413 | return ret; | |
414 | } | |
ee08c6ec | 415 | |
bd1a5c84 | 416 | void unreg_event_syscall_exit(struct ftrace_event_call *call) |
fb34a08c JB |
417 | { |
418 | int num; | |
ee08c6ec | 419 | |
c252f657 | 420 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 421 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
422 | return; |
423 | mutex_lock(&syscall_trace_lock); | |
424 | sys_refcount_exit--; | |
425 | clear_bit(num, enabled_exit_syscalls); | |
426 | if (!sys_refcount_exit) | |
38516ab5 | 427 | unregister_trace_sys_exit(ftrace_syscall_exit, NULL); |
fb34a08c | 428 | mutex_unlock(&syscall_trace_lock); |
ee08c6ec | 429 | } |
fb34a08c | 430 | |
a1301da0 LJ |
431 | int init_syscall_trace(struct ftrace_event_call *call) |
432 | { | |
433 | int id; | |
ba976970 IM |
434 | int num; |
435 | ||
436 | num = ((struct syscall_metadata *)call->data)->syscall_nr; | |
437 | if (num < 0 || num >= NR_syscalls) { | |
438 | pr_debug("syscall %s metadata not mapped, disabling ftrace event\n", | |
439 | ((struct syscall_metadata *)call->data)->name); | |
440 | return -ENOSYS; | |
441 | } | |
a1301da0 | 442 | |
50307a45 LJ |
443 | if (set_syscall_print_fmt(call) < 0) |
444 | return -ENOMEM; | |
445 | ||
c7ef3a90 SR |
446 | id = trace_event_raw_init(call); |
447 | ||
448 | if (id < 0) { | |
50307a45 | 449 | free_syscall_print_fmt(call); |
c7ef3a90 | 450 | return id; |
50307a45 | 451 | } |
c7ef3a90 SR |
452 | |
453 | return id; | |
a1301da0 LJ |
454 | } |
455 | ||
c763ba06 | 456 | unsigned long __init __weak arch_syscall_addr(int nr) |
e7b8e675 MF |
457 | { |
458 | return (unsigned long)sys_call_table[nr]; | |
459 | } | |
460 | ||
c44fc770 FW |
461 | int __init init_ftrace_syscalls(void) |
462 | { | |
463 | struct syscall_metadata *meta; | |
464 | unsigned long addr; | |
465 | int i; | |
466 | ||
467 | syscalls_metadata = kzalloc(sizeof(*syscalls_metadata) * | |
468 | NR_syscalls, GFP_KERNEL); | |
469 | if (!syscalls_metadata) { | |
470 | WARN_ON(1); | |
471 | return -ENOMEM; | |
472 | } | |
473 | ||
474 | for (i = 0; i < NR_syscalls; i++) { | |
475 | addr = arch_syscall_addr(i); | |
476 | meta = find_syscall_meta(addr); | |
c252f657 LJ |
477 | if (!meta) |
478 | continue; | |
479 | ||
480 | meta->syscall_nr = i; | |
c44fc770 FW |
481 | syscalls_metadata[i] = meta; |
482 | } | |
483 | ||
484 | return 0; | |
485 | } | |
486 | core_initcall(init_ftrace_syscalls); | |
487 | ||
07b139c8 | 488 | #ifdef CONFIG_PERF_EVENTS |
19007a67 | 489 | |
97d5a220 FW |
490 | static DECLARE_BITMAP(enabled_perf_enter_syscalls, NR_syscalls); |
491 | static DECLARE_BITMAP(enabled_perf_exit_syscalls, NR_syscalls); | |
492 | static int sys_perf_refcount_enter; | |
493 | static int sys_perf_refcount_exit; | |
f4b5ffcc | 494 | |
38516ab5 | 495 | static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id) |
f4b5ffcc JB |
496 | { |
497 | struct syscall_metadata *sys_data; | |
20ab4425 | 498 | struct syscall_trace_enter *rec; |
1c024eca | 499 | struct hlist_head *head; |
f4b5ffcc | 500 | int syscall_nr; |
4ed7c92d | 501 | int rctx; |
19007a67 | 502 | int size; |
f4b5ffcc JB |
503 | |
504 | syscall_nr = syscall_get_nr(current, regs); | |
97d5a220 | 505 | if (!test_bit(syscall_nr, enabled_perf_enter_syscalls)) |
f4b5ffcc JB |
506 | return; |
507 | ||
508 | sys_data = syscall_nr_to_meta(syscall_nr); | |
509 | if (!sys_data) | |
510 | return; | |
511 | ||
19007a67 FW |
512 | /* get the size after alignment with the u32 buffer size field */ |
513 | size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec); | |
514 | size = ALIGN(size + sizeof(u32), sizeof(u64)); | |
515 | size -= sizeof(u32); | |
516 | ||
97d5a220 FW |
517 | if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, |
518 | "perf buffer not large enough")) | |
20ab4425 FW |
519 | return; |
520 | ||
97d5a220 | 521 | rec = (struct syscall_trace_enter *)perf_trace_buf_prepare(size, |
ff5f149b | 522 | sys_data->enter_event->event.type, regs, &rctx); |
430ad5a6 XG |
523 | if (!rec) |
524 | return; | |
20ab4425 | 525 | |
20ab4425 FW |
526 | rec->nr = syscall_nr; |
527 | syscall_get_arguments(current, regs, 0, sys_data->nb_args, | |
528 | (unsigned long *)&rec->args); | |
1c024eca | 529 | |
3771f077 | 530 | head = this_cpu_ptr(sys_data->enter_event->perf_events); |
1c024eca | 531 | perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head); |
f4b5ffcc JB |
532 | } |
533 | ||
97d5a220 | 534 | int perf_sysenter_enable(struct ftrace_event_call *call) |
f4b5ffcc JB |
535 | { |
536 | int ret = 0; | |
537 | int num; | |
538 | ||
3bbe84e9 | 539 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
540 | |
541 | mutex_lock(&syscall_trace_lock); | |
97d5a220 | 542 | if (!sys_perf_refcount_enter) |
38516ab5 | 543 | ret = register_trace_sys_enter(perf_syscall_enter, NULL); |
f4b5ffcc JB |
544 | if (ret) { |
545 | pr_info("event trace: Could not activate" | |
546 | "syscall entry trace point"); | |
547 | } else { | |
97d5a220 FW |
548 | set_bit(num, enabled_perf_enter_syscalls); |
549 | sys_perf_refcount_enter++; | |
f4b5ffcc JB |
550 | } |
551 | mutex_unlock(&syscall_trace_lock); | |
552 | return ret; | |
553 | } | |
554 | ||
97d5a220 | 555 | void perf_sysenter_disable(struct ftrace_event_call *call) |
f4b5ffcc JB |
556 | { |
557 | int num; | |
558 | ||
3bbe84e9 | 559 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
560 | |
561 | mutex_lock(&syscall_trace_lock); | |
97d5a220 FW |
562 | sys_perf_refcount_enter--; |
563 | clear_bit(num, enabled_perf_enter_syscalls); | |
564 | if (!sys_perf_refcount_enter) | |
38516ab5 | 565 | unregister_trace_sys_enter(perf_syscall_enter, NULL); |
f4b5ffcc JB |
566 | mutex_unlock(&syscall_trace_lock); |
567 | } | |
568 | ||
38516ab5 | 569 | static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret) |
f4b5ffcc JB |
570 | { |
571 | struct syscall_metadata *sys_data; | |
20ab4425 | 572 | struct syscall_trace_exit *rec; |
1c024eca | 573 | struct hlist_head *head; |
f4b5ffcc | 574 | int syscall_nr; |
4ed7c92d | 575 | int rctx; |
20ab4425 | 576 | int size; |
f4b5ffcc JB |
577 | |
578 | syscall_nr = syscall_get_nr(current, regs); | |
97d5a220 | 579 | if (!test_bit(syscall_nr, enabled_perf_exit_syscalls)) |
f4b5ffcc JB |
580 | return; |
581 | ||
582 | sys_data = syscall_nr_to_meta(syscall_nr); | |
583 | if (!sys_data) | |
584 | return; | |
585 | ||
20ab4425 FW |
586 | /* We can probably do that at build time */ |
587 | size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64)); | |
588 | size -= sizeof(u32); | |
19007a67 | 589 | |
20ab4425 FW |
590 | /* |
591 | * Impossible, but be paranoid with the future | |
592 | * How to put this check outside runtime? | |
593 | */ | |
97d5a220 FW |
594 | if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, |
595 | "exit event has grown above perf buffer size")) | |
20ab4425 FW |
596 | return; |
597 | ||
97d5a220 | 598 | rec = (struct syscall_trace_exit *)perf_trace_buf_prepare(size, |
ff5f149b | 599 | sys_data->exit_event->event.type, regs, &rctx); |
430ad5a6 XG |
600 | if (!rec) |
601 | return; | |
20ab4425 | 602 | |
20ab4425 FW |
603 | rec->nr = syscall_nr; |
604 | rec->ret = syscall_get_return_value(current, regs); | |
605 | ||
3771f077 | 606 | head = this_cpu_ptr(sys_data->exit_event->perf_events); |
1c024eca | 607 | perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head); |
f4b5ffcc JB |
608 | } |
609 | ||
97d5a220 | 610 | int perf_sysexit_enable(struct ftrace_event_call *call) |
f4b5ffcc JB |
611 | { |
612 | int ret = 0; | |
613 | int num; | |
614 | ||
3bbe84e9 | 615 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
616 | |
617 | mutex_lock(&syscall_trace_lock); | |
97d5a220 | 618 | if (!sys_perf_refcount_exit) |
38516ab5 | 619 | ret = register_trace_sys_exit(perf_syscall_exit, NULL); |
f4b5ffcc JB |
620 | if (ret) { |
621 | pr_info("event trace: Could not activate" | |
6574658b | 622 | "syscall exit trace point"); |
f4b5ffcc | 623 | } else { |
97d5a220 FW |
624 | set_bit(num, enabled_perf_exit_syscalls); |
625 | sys_perf_refcount_exit++; | |
f4b5ffcc JB |
626 | } |
627 | mutex_unlock(&syscall_trace_lock); | |
628 | return ret; | |
629 | } | |
630 | ||
97d5a220 | 631 | void perf_sysexit_disable(struct ftrace_event_call *call) |
f4b5ffcc JB |
632 | { |
633 | int num; | |
634 | ||
3bbe84e9 | 635 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
636 | |
637 | mutex_lock(&syscall_trace_lock); | |
97d5a220 FW |
638 | sys_perf_refcount_exit--; |
639 | clear_bit(num, enabled_perf_exit_syscalls); | |
640 | if (!sys_perf_refcount_exit) | |
38516ab5 | 641 | unregister_trace_sys_exit(perf_syscall_exit, NULL); |
f4b5ffcc JB |
642 | mutex_unlock(&syscall_trace_lock); |
643 | } | |
644 | ||
07b139c8 | 645 | #endif /* CONFIG_PERF_EVENTS */ |
f4b5ffcc | 646 | |
2239291a SR |
647 | static int syscall_enter_register(struct ftrace_event_call *event, |
648 | enum trace_reg type) | |
649 | { | |
650 | switch (type) { | |
651 | case TRACE_REG_REGISTER: | |
652 | return reg_event_syscall_enter(event); | |
653 | case TRACE_REG_UNREGISTER: | |
654 | unreg_event_syscall_enter(event); | |
655 | return 0; | |
656 | ||
657 | #ifdef CONFIG_PERF_EVENTS | |
658 | case TRACE_REG_PERF_REGISTER: | |
659 | return perf_sysenter_enable(event); | |
660 | case TRACE_REG_PERF_UNREGISTER: | |
661 | perf_sysenter_disable(event); | |
662 | return 0; | |
663 | #endif | |
664 | } | |
665 | return 0; | |
666 | } | |
667 | ||
668 | static int syscall_exit_register(struct ftrace_event_call *event, | |
669 | enum trace_reg type) | |
670 | { | |
671 | switch (type) { | |
672 | case TRACE_REG_REGISTER: | |
673 | return reg_event_syscall_exit(event); | |
674 | case TRACE_REG_UNREGISTER: | |
675 | unreg_event_syscall_exit(event); | |
676 | return 0; | |
677 | ||
678 | #ifdef CONFIG_PERF_EVENTS | |
679 | case TRACE_REG_PERF_REGISTER: | |
680 | return perf_sysexit_enable(event); | |
681 | case TRACE_REG_PERF_UNREGISTER: | |
682 | perf_sysexit_disable(event); | |
683 | return 0; | |
684 | #endif | |
685 | } | |
686 | return 0; | |
687 | } |