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 | ||
ae07f551 IM |
88 | if (arch_syscall_match_sym_name(str, "sys_ni_syscall")) |
89 | return NULL; | |
90 | ||
c44fc770 | 91 | for ( ; start < stop; start++) { |
b2d55496 | 92 | if ((*start)->name && arch_syscall_match_sym_name(str, (*start)->name)) |
3d56e331 | 93 | return *start; |
c44fc770 FW |
94 | } |
95 | return NULL; | |
96 | } | |
97 | ||
98 | static struct syscall_metadata *syscall_nr_to_meta(int nr) | |
99 | { | |
100 | if (!syscalls_metadata || nr >= NR_syscalls || nr < 0) | |
101 | return NULL; | |
102 | ||
103 | return syscalls_metadata[nr]; | |
104 | } | |
105 | ||
bed1ffca | 106 | enum print_line_t |
a9a57763 SR |
107 | print_syscall_enter(struct trace_iterator *iter, int flags, |
108 | struct trace_event *event) | |
bed1ffca FW |
109 | { |
110 | struct trace_seq *s = &iter->seq; | |
111 | struct trace_entry *ent = iter->ent; | |
112 | struct syscall_trace_enter *trace; | |
113 | struct syscall_metadata *entry; | |
114 | int i, ret, syscall; | |
115 | ||
64c12e04 | 116 | trace = (typeof(trace))ent; |
bed1ffca | 117 | syscall = trace->nr; |
bed1ffca | 118 | entry = syscall_nr_to_meta(syscall); |
64c12e04 | 119 | |
bed1ffca FW |
120 | if (!entry) |
121 | goto end; | |
122 | ||
32c0edae | 123 | if (entry->enter_event->event.type != ent->type) { |
64c12e04 JB |
124 | WARN_ON_ONCE(1); |
125 | goto end; | |
126 | } | |
127 | ||
bed1ffca FW |
128 | ret = trace_seq_printf(s, "%s(", entry->name); |
129 | if (!ret) | |
130 | return TRACE_TYPE_PARTIAL_LINE; | |
131 | ||
132 | for (i = 0; i < entry->nb_args; i++) { | |
133 | /* parameter types */ | |
ba8b3a40 | 134 | if (trace_flags & TRACE_ITER_VERBOSE) { |
bed1ffca FW |
135 | ret = trace_seq_printf(s, "%s ", entry->types[i]); |
136 | if (!ret) | |
137 | return TRACE_TYPE_PARTIAL_LINE; | |
138 | } | |
139 | /* parameter values */ | |
4539f077 | 140 | ret = trace_seq_printf(s, "%s: %lx%s", entry->args[i], |
bed1ffca | 141 | trace->args[i], |
4539f077 | 142 | i == entry->nb_args - 1 ? "" : ", "); |
bed1ffca FW |
143 | if (!ret) |
144 | return TRACE_TYPE_PARTIAL_LINE; | |
145 | } | |
146 | ||
4539f077 LZ |
147 | ret = trace_seq_putc(s, ')'); |
148 | if (!ret) | |
149 | return TRACE_TYPE_PARTIAL_LINE; | |
150 | ||
bed1ffca | 151 | end: |
4539f077 LZ |
152 | ret = trace_seq_putc(s, '\n'); |
153 | if (!ret) | |
154 | return TRACE_TYPE_PARTIAL_LINE; | |
155 | ||
bed1ffca FW |
156 | return TRACE_TYPE_HANDLED; |
157 | } | |
158 | ||
159 | enum print_line_t | |
a9a57763 SR |
160 | print_syscall_exit(struct trace_iterator *iter, int flags, |
161 | struct trace_event *event) | |
bed1ffca FW |
162 | { |
163 | struct trace_seq *s = &iter->seq; | |
164 | struct trace_entry *ent = iter->ent; | |
165 | struct syscall_trace_exit *trace; | |
166 | int syscall; | |
167 | struct syscall_metadata *entry; | |
168 | int ret; | |
169 | ||
64c12e04 | 170 | trace = (typeof(trace))ent; |
bed1ffca | 171 | syscall = trace->nr; |
bed1ffca | 172 | entry = syscall_nr_to_meta(syscall); |
64c12e04 | 173 | |
bed1ffca FW |
174 | if (!entry) { |
175 | trace_seq_printf(s, "\n"); | |
176 | return TRACE_TYPE_HANDLED; | |
177 | } | |
178 | ||
32c0edae | 179 | if (entry->exit_event->event.type != ent->type) { |
64c12e04 JB |
180 | WARN_ON_ONCE(1); |
181 | return TRACE_TYPE_UNHANDLED; | |
182 | } | |
183 | ||
bed1ffca FW |
184 | ret = trace_seq_printf(s, "%s -> 0x%lx\n", entry->name, |
185 | trace->ret); | |
186 | if (!ret) | |
187 | return TRACE_TYPE_PARTIAL_LINE; | |
188 | ||
189 | return TRACE_TYPE_HANDLED; | |
190 | } | |
191 | ||
e6971969 LZ |
192 | extern char *__bad_type_size(void); |
193 | ||
194 | #define SYSCALL_FIELD(type, name) \ | |
195 | sizeof(type) != sizeof(trace.name) ? \ | |
196 | __bad_type_size() : \ | |
26a50744 TZ |
197 | #type, #name, offsetof(typeof(trace), name), \ |
198 | sizeof(trace.name), is_signed_type(type) | |
e6971969 | 199 | |
50307a45 LJ |
200 | static |
201 | int __set_enter_print_fmt(struct syscall_metadata *entry, char *buf, int len) | |
202 | { | |
203 | int i; | |
204 | int pos = 0; | |
205 | ||
206 | /* When len=0, we just calculate the needed length */ | |
207 | #define LEN_OR_ZERO (len ? len - pos : 0) | |
208 | ||
209 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); | |
210 | for (i = 0; i < entry->nb_args; i++) { | |
211 | pos += snprintf(buf + pos, LEN_OR_ZERO, "%s: 0x%%0%zulx%s", | |
212 | entry->args[i], sizeof(unsigned long), | |
213 | i == entry->nb_args - 1 ? "" : ", "); | |
214 | } | |
215 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); | |
216 | ||
217 | for (i = 0; i < entry->nb_args; i++) { | |
218 | pos += snprintf(buf + pos, LEN_OR_ZERO, | |
219 | ", ((unsigned long)(REC->%s))", entry->args[i]); | |
220 | } | |
221 | ||
222 | #undef LEN_OR_ZERO | |
223 | ||
224 | /* return the length of print_fmt */ | |
225 | return pos; | |
226 | } | |
227 | ||
228 | static int set_syscall_print_fmt(struct ftrace_event_call *call) | |
229 | { | |
230 | char *print_fmt; | |
231 | int len; | |
232 | struct syscall_metadata *entry = call->data; | |
233 | ||
234 | if (entry->enter_event != call) { | |
235 | call->print_fmt = "\"0x%lx\", REC->ret"; | |
236 | return 0; | |
237 | } | |
238 | ||
239 | /* First: called with 0 length to calculate the needed length */ | |
240 | len = __set_enter_print_fmt(entry, NULL, 0); | |
241 | ||
242 | print_fmt = kmalloc(len + 1, GFP_KERNEL); | |
243 | if (!print_fmt) | |
244 | return -ENOMEM; | |
245 | ||
246 | /* Second: actually write the @print_fmt */ | |
247 | __set_enter_print_fmt(entry, print_fmt, len + 1); | |
248 | call->print_fmt = print_fmt; | |
249 | ||
250 | return 0; | |
251 | } | |
252 | ||
253 | static void free_syscall_print_fmt(struct ftrace_event_call *call) | |
254 | { | |
255 | struct syscall_metadata *entry = call->data; | |
256 | ||
257 | if (entry->enter_event == call) | |
258 | kfree(call->print_fmt); | |
259 | } | |
260 | ||
2e33af02 | 261 | static int syscall_enter_define_fields(struct ftrace_event_call *call) |
540b7b8d LZ |
262 | { |
263 | struct syscall_trace_enter trace; | |
31c16b13 | 264 | struct syscall_metadata *meta = call->data; |
540b7b8d | 265 | int ret; |
540b7b8d LZ |
266 | int i; |
267 | int offset = offsetof(typeof(trace), args); | |
268 | ||
0f1ef51d LJ |
269 | ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER); |
270 | if (ret) | |
271 | return ret; | |
272 | ||
540b7b8d | 273 | for (i = 0; i < meta->nb_args; i++) { |
aeaeae11 FW |
274 | ret = trace_define_field(call, meta->types[i], |
275 | meta->args[i], offset, | |
43b51ead LZ |
276 | sizeof(unsigned long), 0, |
277 | FILTER_OTHER); | |
540b7b8d LZ |
278 | offset += sizeof(unsigned long); |
279 | } | |
280 | ||
281 | return ret; | |
282 | } | |
283 | ||
2e33af02 | 284 | static int syscall_exit_define_fields(struct ftrace_event_call *call) |
540b7b8d LZ |
285 | { |
286 | struct syscall_trace_exit trace; | |
287 | int ret; | |
288 | ||
0f1ef51d LJ |
289 | ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER); |
290 | if (ret) | |
291 | return ret; | |
292 | ||
26a50744 | 293 | ret = trace_define_field(call, SYSCALL_FIELD(long, ret), |
43b51ead | 294 | FILTER_OTHER); |
540b7b8d LZ |
295 | |
296 | return ret; | |
297 | } | |
298 | ||
38516ab5 | 299 | void ftrace_syscall_enter(void *ignore, struct pt_regs *regs, long id) |
ee08c6ec | 300 | { |
bed1ffca FW |
301 | struct syscall_trace_enter *entry; |
302 | struct syscall_metadata *sys_data; | |
303 | struct ring_buffer_event *event; | |
e77405ad | 304 | struct ring_buffer *buffer; |
bed1ffca | 305 | int size; |
ee08c6ec FW |
306 | int syscall_nr; |
307 | ||
308 | syscall_nr = syscall_get_nr(current, regs); | |
cd0980fc HB |
309 | if (syscall_nr < 0) |
310 | return; | |
fb34a08c JB |
311 | if (!test_bit(syscall_nr, enabled_enter_syscalls)) |
312 | return; | |
ee08c6ec | 313 | |
bed1ffca FW |
314 | sys_data = syscall_nr_to_meta(syscall_nr); |
315 | if (!sys_data) | |
316 | return; | |
317 | ||
318 | size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args; | |
319 | ||
fcc19438 | 320 | event = trace_current_buffer_lock_reserve(&buffer, |
32c0edae | 321 | sys_data->enter_event->event.type, size, 0, 0); |
bed1ffca FW |
322 | if (!event) |
323 | return; | |
324 | ||
325 | entry = ring_buffer_event_data(event); | |
326 | entry->nr = syscall_nr; | |
327 | syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args); | |
328 | ||
e77405ad SR |
329 | if (!filter_current_check_discard(buffer, sys_data->enter_event, |
330 | entry, event)) | |
331 | trace_current_buffer_unlock_commit(buffer, event, 0, 0); | |
ee08c6ec FW |
332 | } |
333 | ||
38516ab5 | 334 | void ftrace_syscall_exit(void *ignore, struct pt_regs *regs, long ret) |
ee08c6ec | 335 | { |
bed1ffca FW |
336 | struct syscall_trace_exit *entry; |
337 | struct syscall_metadata *sys_data; | |
338 | struct ring_buffer_event *event; | |
e77405ad | 339 | struct ring_buffer *buffer; |
ee08c6ec FW |
340 | int syscall_nr; |
341 | ||
342 | syscall_nr = syscall_get_nr(current, regs); | |
cd0980fc HB |
343 | if (syscall_nr < 0) |
344 | return; | |
fb34a08c JB |
345 | if (!test_bit(syscall_nr, enabled_exit_syscalls)) |
346 | return; | |
ee08c6ec | 347 | |
bed1ffca FW |
348 | sys_data = syscall_nr_to_meta(syscall_nr); |
349 | if (!sys_data) | |
350 | return; | |
351 | ||
fcc19438 | 352 | event = trace_current_buffer_lock_reserve(&buffer, |
32c0edae | 353 | sys_data->exit_event->event.type, sizeof(*entry), 0, 0); |
bed1ffca FW |
354 | if (!event) |
355 | return; | |
356 | ||
357 | entry = ring_buffer_event_data(event); | |
358 | entry->nr = syscall_nr; | |
359 | entry->ret = syscall_get_return_value(current, regs); | |
360 | ||
e77405ad SR |
361 | if (!filter_current_check_discard(buffer, sys_data->exit_event, |
362 | entry, event)) | |
363 | trace_current_buffer_unlock_commit(buffer, event, 0, 0); | |
ee08c6ec FW |
364 | } |
365 | ||
bd1a5c84 | 366 | int reg_event_syscall_enter(struct ftrace_event_call *call) |
ee08c6ec | 367 | { |
fb34a08c JB |
368 | int ret = 0; |
369 | int num; | |
fb34a08c | 370 | |
c252f657 | 371 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 372 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
373 | return -ENOSYS; |
374 | mutex_lock(&syscall_trace_lock); | |
375 | if (!sys_refcount_enter) | |
38516ab5 | 376 | ret = register_trace_sys_enter(ftrace_syscall_enter, NULL); |
3b8e4273 | 377 | if (!ret) { |
fb34a08c JB |
378 | set_bit(num, enabled_enter_syscalls); |
379 | sys_refcount_enter++; | |
380 | } | |
381 | mutex_unlock(&syscall_trace_lock); | |
382 | return ret; | |
ee08c6ec FW |
383 | } |
384 | ||
bd1a5c84 | 385 | void unreg_event_syscall_enter(struct ftrace_event_call *call) |
ee08c6ec | 386 | { |
fb34a08c | 387 | int num; |
ee08c6ec | 388 | |
c252f657 | 389 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 390 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
391 | return; |
392 | mutex_lock(&syscall_trace_lock); | |
393 | sys_refcount_enter--; | |
394 | clear_bit(num, enabled_enter_syscalls); | |
395 | if (!sys_refcount_enter) | |
38516ab5 | 396 | unregister_trace_sys_enter(ftrace_syscall_enter, NULL); |
fb34a08c JB |
397 | mutex_unlock(&syscall_trace_lock); |
398 | } | |
ee08c6ec | 399 | |
bd1a5c84 | 400 | int reg_event_syscall_exit(struct ftrace_event_call *call) |
ee08c6ec | 401 | { |
fb34a08c JB |
402 | int ret = 0; |
403 | int num; | |
fb34a08c | 404 | |
c252f657 | 405 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 406 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
407 | return -ENOSYS; |
408 | mutex_lock(&syscall_trace_lock); | |
409 | if (!sys_refcount_exit) | |
38516ab5 | 410 | ret = register_trace_sys_exit(ftrace_syscall_exit, NULL); |
3b8e4273 | 411 | if (!ret) { |
fb34a08c JB |
412 | set_bit(num, enabled_exit_syscalls); |
413 | sys_refcount_exit++; | |
ee08c6ec | 414 | } |
fb34a08c JB |
415 | mutex_unlock(&syscall_trace_lock); |
416 | return ret; | |
417 | } | |
ee08c6ec | 418 | |
bd1a5c84 | 419 | void unreg_event_syscall_exit(struct ftrace_event_call *call) |
fb34a08c JB |
420 | { |
421 | int num; | |
ee08c6ec | 422 | |
c252f657 | 423 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
3773b389 | 424 | if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) |
fb34a08c JB |
425 | return; |
426 | mutex_lock(&syscall_trace_lock); | |
427 | sys_refcount_exit--; | |
428 | clear_bit(num, enabled_exit_syscalls); | |
429 | if (!sys_refcount_exit) | |
38516ab5 | 430 | unregister_trace_sys_exit(ftrace_syscall_exit, NULL); |
fb34a08c | 431 | mutex_unlock(&syscall_trace_lock); |
ee08c6ec | 432 | } |
fb34a08c | 433 | |
a1301da0 LJ |
434 | int init_syscall_trace(struct ftrace_event_call *call) |
435 | { | |
436 | int id; | |
ba976970 IM |
437 | int num; |
438 | ||
439 | num = ((struct syscall_metadata *)call->data)->syscall_nr; | |
440 | if (num < 0 || num >= NR_syscalls) { | |
441 | pr_debug("syscall %s metadata not mapped, disabling ftrace event\n", | |
442 | ((struct syscall_metadata *)call->data)->name); | |
443 | return -ENOSYS; | |
444 | } | |
a1301da0 | 445 | |
50307a45 LJ |
446 | if (set_syscall_print_fmt(call) < 0) |
447 | return -ENOMEM; | |
448 | ||
c7ef3a90 SR |
449 | id = trace_event_raw_init(call); |
450 | ||
451 | if (id < 0) { | |
50307a45 | 452 | free_syscall_print_fmt(call); |
c7ef3a90 | 453 | return id; |
50307a45 | 454 | } |
c7ef3a90 SR |
455 | |
456 | return id; | |
a1301da0 LJ |
457 | } |
458 | ||
c763ba06 | 459 | unsigned long __init __weak arch_syscall_addr(int nr) |
e7b8e675 MF |
460 | { |
461 | return (unsigned long)sys_call_table[nr]; | |
462 | } | |
463 | ||
c44fc770 FW |
464 | int __init init_ftrace_syscalls(void) |
465 | { | |
466 | struct syscall_metadata *meta; | |
467 | unsigned long addr; | |
468 | int i; | |
469 | ||
470 | syscalls_metadata = kzalloc(sizeof(*syscalls_metadata) * | |
471 | NR_syscalls, GFP_KERNEL); | |
472 | if (!syscalls_metadata) { | |
473 | WARN_ON(1); | |
474 | return -ENOMEM; | |
475 | } | |
476 | ||
477 | for (i = 0; i < NR_syscalls; i++) { | |
478 | addr = arch_syscall_addr(i); | |
479 | meta = find_syscall_meta(addr); | |
c252f657 LJ |
480 | if (!meta) |
481 | continue; | |
482 | ||
483 | meta->syscall_nr = i; | |
c44fc770 FW |
484 | syscalls_metadata[i] = meta; |
485 | } | |
486 | ||
487 | return 0; | |
488 | } | |
489 | core_initcall(init_ftrace_syscalls); | |
490 | ||
07b139c8 | 491 | #ifdef CONFIG_PERF_EVENTS |
19007a67 | 492 | |
97d5a220 FW |
493 | static DECLARE_BITMAP(enabled_perf_enter_syscalls, NR_syscalls); |
494 | static DECLARE_BITMAP(enabled_perf_exit_syscalls, NR_syscalls); | |
495 | static int sys_perf_refcount_enter; | |
496 | static int sys_perf_refcount_exit; | |
f4b5ffcc | 497 | |
38516ab5 | 498 | static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id) |
f4b5ffcc JB |
499 | { |
500 | struct syscall_metadata *sys_data; | |
20ab4425 | 501 | struct syscall_trace_enter *rec; |
1c024eca | 502 | struct hlist_head *head; |
f4b5ffcc | 503 | int syscall_nr; |
4ed7c92d | 504 | int rctx; |
19007a67 | 505 | int size; |
f4b5ffcc JB |
506 | |
507 | syscall_nr = syscall_get_nr(current, regs); | |
97d5a220 | 508 | if (!test_bit(syscall_nr, enabled_perf_enter_syscalls)) |
f4b5ffcc JB |
509 | return; |
510 | ||
511 | sys_data = syscall_nr_to_meta(syscall_nr); | |
512 | if (!sys_data) | |
513 | return; | |
514 | ||
19007a67 FW |
515 | /* get the size after alignment with the u32 buffer size field */ |
516 | size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec); | |
517 | size = ALIGN(size + sizeof(u32), sizeof(u64)); | |
518 | size -= sizeof(u32); | |
519 | ||
97d5a220 FW |
520 | if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, |
521 | "perf buffer not large enough")) | |
20ab4425 FW |
522 | return; |
523 | ||
97d5a220 | 524 | rec = (struct syscall_trace_enter *)perf_trace_buf_prepare(size, |
ff5f149b | 525 | sys_data->enter_event->event.type, regs, &rctx); |
430ad5a6 XG |
526 | if (!rec) |
527 | return; | |
20ab4425 | 528 | |
20ab4425 FW |
529 | rec->nr = syscall_nr; |
530 | syscall_get_arguments(current, regs, 0, sys_data->nb_args, | |
531 | (unsigned long *)&rec->args); | |
1c024eca | 532 | |
3771f077 | 533 | head = this_cpu_ptr(sys_data->enter_event->perf_events); |
1c024eca | 534 | perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head); |
f4b5ffcc JB |
535 | } |
536 | ||
97d5a220 | 537 | int perf_sysenter_enable(struct ftrace_event_call *call) |
f4b5ffcc JB |
538 | { |
539 | int ret = 0; | |
540 | int num; | |
541 | ||
3bbe84e9 | 542 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
543 | |
544 | mutex_lock(&syscall_trace_lock); | |
97d5a220 | 545 | if (!sys_perf_refcount_enter) |
38516ab5 | 546 | ret = register_trace_sys_enter(perf_syscall_enter, NULL); |
f4b5ffcc JB |
547 | if (ret) { |
548 | pr_info("event trace: Could not activate" | |
549 | "syscall entry trace point"); | |
550 | } else { | |
97d5a220 FW |
551 | set_bit(num, enabled_perf_enter_syscalls); |
552 | sys_perf_refcount_enter++; | |
f4b5ffcc JB |
553 | } |
554 | mutex_unlock(&syscall_trace_lock); | |
555 | return ret; | |
556 | } | |
557 | ||
97d5a220 | 558 | void perf_sysenter_disable(struct ftrace_event_call *call) |
f4b5ffcc JB |
559 | { |
560 | int num; | |
561 | ||
3bbe84e9 | 562 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
563 | |
564 | mutex_lock(&syscall_trace_lock); | |
97d5a220 FW |
565 | sys_perf_refcount_enter--; |
566 | clear_bit(num, enabled_perf_enter_syscalls); | |
567 | if (!sys_perf_refcount_enter) | |
38516ab5 | 568 | unregister_trace_sys_enter(perf_syscall_enter, NULL); |
f4b5ffcc JB |
569 | mutex_unlock(&syscall_trace_lock); |
570 | } | |
571 | ||
38516ab5 | 572 | static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret) |
f4b5ffcc JB |
573 | { |
574 | struct syscall_metadata *sys_data; | |
20ab4425 | 575 | struct syscall_trace_exit *rec; |
1c024eca | 576 | struct hlist_head *head; |
f4b5ffcc | 577 | int syscall_nr; |
4ed7c92d | 578 | int rctx; |
20ab4425 | 579 | int size; |
f4b5ffcc JB |
580 | |
581 | syscall_nr = syscall_get_nr(current, regs); | |
97d5a220 | 582 | if (!test_bit(syscall_nr, enabled_perf_exit_syscalls)) |
f4b5ffcc JB |
583 | return; |
584 | ||
585 | sys_data = syscall_nr_to_meta(syscall_nr); | |
586 | if (!sys_data) | |
587 | return; | |
588 | ||
20ab4425 FW |
589 | /* We can probably do that at build time */ |
590 | size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64)); | |
591 | size -= sizeof(u32); | |
19007a67 | 592 | |
20ab4425 FW |
593 | /* |
594 | * Impossible, but be paranoid with the future | |
595 | * How to put this check outside runtime? | |
596 | */ | |
97d5a220 FW |
597 | if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, |
598 | "exit event has grown above perf buffer size")) | |
20ab4425 FW |
599 | return; |
600 | ||
97d5a220 | 601 | rec = (struct syscall_trace_exit *)perf_trace_buf_prepare(size, |
ff5f149b | 602 | sys_data->exit_event->event.type, regs, &rctx); |
430ad5a6 XG |
603 | if (!rec) |
604 | return; | |
20ab4425 | 605 | |
20ab4425 FW |
606 | rec->nr = syscall_nr; |
607 | rec->ret = syscall_get_return_value(current, regs); | |
608 | ||
3771f077 | 609 | head = this_cpu_ptr(sys_data->exit_event->perf_events); |
1c024eca | 610 | perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head); |
f4b5ffcc JB |
611 | } |
612 | ||
97d5a220 | 613 | int perf_sysexit_enable(struct ftrace_event_call *call) |
f4b5ffcc JB |
614 | { |
615 | int ret = 0; | |
616 | int num; | |
617 | ||
3bbe84e9 | 618 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
619 | |
620 | mutex_lock(&syscall_trace_lock); | |
97d5a220 | 621 | if (!sys_perf_refcount_exit) |
38516ab5 | 622 | ret = register_trace_sys_exit(perf_syscall_exit, NULL); |
f4b5ffcc JB |
623 | if (ret) { |
624 | pr_info("event trace: Could not activate" | |
6574658b | 625 | "syscall exit trace point"); |
f4b5ffcc | 626 | } else { |
97d5a220 FW |
627 | set_bit(num, enabled_perf_exit_syscalls); |
628 | sys_perf_refcount_exit++; | |
f4b5ffcc JB |
629 | } |
630 | mutex_unlock(&syscall_trace_lock); | |
631 | return ret; | |
632 | } | |
633 | ||
97d5a220 | 634 | void perf_sysexit_disable(struct ftrace_event_call *call) |
f4b5ffcc JB |
635 | { |
636 | int num; | |
637 | ||
3bbe84e9 | 638 | num = ((struct syscall_metadata *)call->data)->syscall_nr; |
f4b5ffcc JB |
639 | |
640 | mutex_lock(&syscall_trace_lock); | |
97d5a220 FW |
641 | sys_perf_refcount_exit--; |
642 | clear_bit(num, enabled_perf_exit_syscalls); | |
643 | if (!sys_perf_refcount_exit) | |
38516ab5 | 644 | unregister_trace_sys_exit(perf_syscall_exit, NULL); |
f4b5ffcc JB |
645 | mutex_unlock(&syscall_trace_lock); |
646 | } | |
647 | ||
07b139c8 | 648 | #endif /* CONFIG_PERF_EVENTS */ |
f4b5ffcc | 649 | |
2239291a SR |
650 | static int syscall_enter_register(struct ftrace_event_call *event, |
651 | enum trace_reg type) | |
652 | { | |
653 | switch (type) { | |
654 | case TRACE_REG_REGISTER: | |
655 | return reg_event_syscall_enter(event); | |
656 | case TRACE_REG_UNREGISTER: | |
657 | unreg_event_syscall_enter(event); | |
658 | return 0; | |
659 | ||
660 | #ifdef CONFIG_PERF_EVENTS | |
661 | case TRACE_REG_PERF_REGISTER: | |
662 | return perf_sysenter_enable(event); | |
663 | case TRACE_REG_PERF_UNREGISTER: | |
664 | perf_sysenter_disable(event); | |
665 | return 0; | |
666 | #endif | |
667 | } | |
668 | return 0; | |
669 | } | |
670 | ||
671 | static int syscall_exit_register(struct ftrace_event_call *event, | |
672 | enum trace_reg type) | |
673 | { | |
674 | switch (type) { | |
675 | case TRACE_REG_REGISTER: | |
676 | return reg_event_syscall_exit(event); | |
677 | case TRACE_REG_UNREGISTER: | |
678 | unreg_event_syscall_exit(event); | |
679 | return 0; | |
680 | ||
681 | #ifdef CONFIG_PERF_EVENTS | |
682 | case TRACE_REG_PERF_REGISTER: | |
683 | return perf_sysexit_enable(event); | |
684 | case TRACE_REG_PERF_UNREGISTER: | |
685 | perf_sysexit_disable(event); | |
686 | return 0; | |
687 | #endif | |
688 | } | |
689 | return 0; | |
690 | } |