Merge branch 'tracing/core' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic...
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / kernel / trace / trace_syscalls.c
blob85291c4de406ecd8ed8d772cfc9e784da11ed485
1 #include <trace/syscall.h>
2 #include <trace/events/syscalls.h>
3 #include <linux/kernel.h>
4 #include <linux/ftrace.h>
5 #include <linux/perf_counter.h>
6 #include <asm/syscall.h>
8 #include "trace_output.h"
9 #include "trace.h"
11 static DEFINE_MUTEX(syscall_trace_lock);
12 static int sys_refcount_enter;
13 static int sys_refcount_exit;
14 static DECLARE_BITMAP(enabled_enter_syscalls, FTRACE_SYSCALL_MAX);
15 static DECLARE_BITMAP(enabled_exit_syscalls, FTRACE_SYSCALL_MAX);
17 enum print_line_t
18 print_syscall_enter(struct trace_iterator *iter, int flags)
20 struct trace_seq *s = &iter->seq;
21 struct trace_entry *ent = iter->ent;
22 struct syscall_trace_enter *trace;
23 struct syscall_metadata *entry;
24 int i, ret, syscall;
26 trace = (typeof(trace))ent;
27 syscall = trace->nr;
28 entry = syscall_nr_to_meta(syscall);
30 if (!entry)
31 goto end;
33 if (entry->enter_id != ent->type) {
34 WARN_ON_ONCE(1);
35 goto end;
38 ret = trace_seq_printf(s, "%s(", entry->name);
39 if (!ret)
40 return TRACE_TYPE_PARTIAL_LINE;
42 for (i = 0; i < entry->nb_args; i++) {
43 /* parameter types */
44 if (trace_flags & TRACE_ITER_VERBOSE) {
45 ret = trace_seq_printf(s, "%s ", entry->types[i]);
46 if (!ret)
47 return TRACE_TYPE_PARTIAL_LINE;
49 /* parameter values */
50 ret = trace_seq_printf(s, "%s: %lx%s", entry->args[i],
51 trace->args[i],
52 i == entry->nb_args - 1 ? "" : ", ");
53 if (!ret)
54 return TRACE_TYPE_PARTIAL_LINE;
57 ret = trace_seq_putc(s, ')');
58 if (!ret)
59 return TRACE_TYPE_PARTIAL_LINE;
61 end:
62 ret = trace_seq_putc(s, '\n');
63 if (!ret)
64 return TRACE_TYPE_PARTIAL_LINE;
66 return TRACE_TYPE_HANDLED;
69 enum print_line_t
70 print_syscall_exit(struct trace_iterator *iter, int flags)
72 struct trace_seq *s = &iter->seq;
73 struct trace_entry *ent = iter->ent;
74 struct syscall_trace_exit *trace;
75 int syscall;
76 struct syscall_metadata *entry;
77 int ret;
79 trace = (typeof(trace))ent;
80 syscall = trace->nr;
81 entry = syscall_nr_to_meta(syscall);
83 if (!entry) {
84 trace_seq_printf(s, "\n");
85 return TRACE_TYPE_HANDLED;
88 if (entry->exit_id != ent->type) {
89 WARN_ON_ONCE(1);
90 return TRACE_TYPE_UNHANDLED;
93 ret = trace_seq_printf(s, "%s -> 0x%lx\n", entry->name,
94 trace->ret);
95 if (!ret)
96 return TRACE_TYPE_PARTIAL_LINE;
98 return TRACE_TYPE_HANDLED;
101 extern char *__bad_type_size(void);
103 #define SYSCALL_FIELD(type, name) \
104 sizeof(type) != sizeof(trace.name) ? \
105 __bad_type_size() : \
106 #type, #name, offsetof(typeof(trace), name), sizeof(trace.name)
108 int syscall_enter_format(struct ftrace_event_call *call, struct trace_seq *s)
110 int i;
111 int nr;
112 int ret;
113 struct syscall_metadata *entry;
114 struct syscall_trace_enter trace;
115 int offset = offsetof(struct syscall_trace_enter, args);
117 nr = syscall_name_to_nr(call->data);
118 entry = syscall_nr_to_meta(nr);
120 if (!entry)
121 return 0;
123 ret = trace_seq_printf(s, "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n",
124 SYSCALL_FIELD(int, nr));
125 if (!ret)
126 return 0;
128 for (i = 0; i < entry->nb_args; i++) {
129 ret = trace_seq_printf(s, "\tfield:%s %s;", entry->types[i],
130 entry->args[i]);
131 if (!ret)
132 return 0;
133 ret = trace_seq_printf(s, "\toffset:%d;\tsize:%zu;\n", offset,
134 sizeof(unsigned long));
135 if (!ret)
136 return 0;
137 offset += sizeof(unsigned long);
140 trace_seq_puts(s, "\nprint fmt: \"");
141 for (i = 0; i < entry->nb_args; i++) {
142 ret = trace_seq_printf(s, "%s: 0x%%0%zulx%s", entry->args[i],
143 sizeof(unsigned long),
144 i == entry->nb_args - 1 ? "" : ", ");
145 if (!ret)
146 return 0;
148 trace_seq_putc(s, '"');
150 for (i = 0; i < entry->nb_args; i++) {
151 ret = trace_seq_printf(s, ", ((unsigned long)(REC->%s))",
152 entry->args[i]);
153 if (!ret)
154 return 0;
157 return trace_seq_putc(s, '\n');
160 int syscall_exit_format(struct ftrace_event_call *call, struct trace_seq *s)
162 int ret;
163 struct syscall_trace_exit trace;
165 ret = trace_seq_printf(s,
166 "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
167 "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n",
168 SYSCALL_FIELD(int, nr),
169 SYSCALL_FIELD(unsigned long, ret));
170 if (!ret)
171 return 0;
173 return trace_seq_printf(s, "\nprint fmt: \"0x%%lx\", REC->ret\n");
176 int syscall_enter_define_fields(struct ftrace_event_call *call)
178 struct syscall_trace_enter trace;
179 struct syscall_metadata *meta;
180 int ret;
181 int nr;
182 int i;
183 int offset = offsetof(typeof(trace), args);
185 nr = syscall_name_to_nr(call->data);
186 meta = syscall_nr_to_meta(nr);
188 if (!meta)
189 return 0;
191 ret = trace_define_common_fields(call);
192 if (ret)
193 return ret;
195 for (i = 0; i < meta->nb_args; i++) {
196 ret = trace_define_field(call, meta->types[i],
197 meta->args[i], offset,
198 sizeof(unsigned long), 0,
199 FILTER_OTHER);
200 offset += sizeof(unsigned long);
203 return ret;
206 int syscall_exit_define_fields(struct ftrace_event_call *call)
208 struct syscall_trace_exit trace;
209 int ret;
211 ret = trace_define_common_fields(call);
212 if (ret)
213 return ret;
215 ret = trace_define_field(call, SYSCALL_FIELD(unsigned long, ret), 0,
216 FILTER_OTHER);
218 return ret;
221 void ftrace_syscall_enter(struct pt_regs *regs, long id)
223 struct syscall_trace_enter *entry;
224 struct syscall_metadata *sys_data;
225 struct ring_buffer_event *event;
226 int size;
227 int syscall_nr;
229 syscall_nr = syscall_get_nr(current, regs);
230 if (!test_bit(syscall_nr, enabled_enter_syscalls))
231 return;
233 sys_data = syscall_nr_to_meta(syscall_nr);
234 if (!sys_data)
235 return;
237 size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;
239 event = trace_current_buffer_lock_reserve(sys_data->enter_id, size,
240 0, 0);
241 if (!event)
242 return;
244 entry = ring_buffer_event_data(event);
245 entry->nr = syscall_nr;
246 syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args);
248 if (!filter_current_check_discard(sys_data->enter_event, entry, event))
249 trace_current_buffer_unlock_commit(event, 0, 0);
252 void ftrace_syscall_exit(struct pt_regs *regs, long ret)
254 struct syscall_trace_exit *entry;
255 struct syscall_metadata *sys_data;
256 struct ring_buffer_event *event;
257 int syscall_nr;
259 syscall_nr = syscall_get_nr(current, regs);
260 if (!test_bit(syscall_nr, enabled_exit_syscalls))
261 return;
263 sys_data = syscall_nr_to_meta(syscall_nr);
264 if (!sys_data)
265 return;
267 event = trace_current_buffer_lock_reserve(sys_data->exit_id,
268 sizeof(*entry), 0, 0);
269 if (!event)
270 return;
272 entry = ring_buffer_event_data(event);
273 entry->nr = syscall_nr;
274 entry->ret = syscall_get_return_value(current, regs);
276 if (!filter_current_check_discard(sys_data->exit_event, entry, event))
277 trace_current_buffer_unlock_commit(event, 0, 0);
280 int reg_event_syscall_enter(void *ptr)
282 int ret = 0;
283 int num;
284 char *name;
286 name = (char *)ptr;
287 num = syscall_name_to_nr(name);
288 if (num < 0 || num >= FTRACE_SYSCALL_MAX)
289 return -ENOSYS;
290 mutex_lock(&syscall_trace_lock);
291 if (!sys_refcount_enter)
292 ret = register_trace_sys_enter(ftrace_syscall_enter);
293 if (ret) {
294 pr_info("event trace: Could not activate"
295 "syscall entry trace point");
296 } else {
297 set_bit(num, enabled_enter_syscalls);
298 sys_refcount_enter++;
300 mutex_unlock(&syscall_trace_lock);
301 return ret;
304 void unreg_event_syscall_enter(void *ptr)
306 int num;
307 char *name;
309 name = (char *)ptr;
310 num = syscall_name_to_nr(name);
311 if (num < 0 || num >= FTRACE_SYSCALL_MAX)
312 return;
313 mutex_lock(&syscall_trace_lock);
314 sys_refcount_enter--;
315 clear_bit(num, enabled_enter_syscalls);
316 if (!sys_refcount_enter)
317 unregister_trace_sys_enter(ftrace_syscall_enter);
318 mutex_unlock(&syscall_trace_lock);
321 int reg_event_syscall_exit(void *ptr)
323 int ret = 0;
324 int num;
325 char *name;
327 name = (char *)ptr;
328 num = syscall_name_to_nr(name);
329 if (num < 0 || num >= FTRACE_SYSCALL_MAX)
330 return -ENOSYS;
331 mutex_lock(&syscall_trace_lock);
332 if (!sys_refcount_exit)
333 ret = register_trace_sys_exit(ftrace_syscall_exit);
334 if (ret) {
335 pr_info("event trace: Could not activate"
336 "syscall exit trace point");
337 } else {
338 set_bit(num, enabled_exit_syscalls);
339 sys_refcount_exit++;
341 mutex_unlock(&syscall_trace_lock);
342 return ret;
345 void unreg_event_syscall_exit(void *ptr)
347 int num;
348 char *name;
350 name = (char *)ptr;
351 num = syscall_name_to_nr(name);
352 if (num < 0 || num >= FTRACE_SYSCALL_MAX)
353 return;
354 mutex_lock(&syscall_trace_lock);
355 sys_refcount_exit--;
356 clear_bit(num, enabled_exit_syscalls);
357 if (!sys_refcount_exit)
358 unregister_trace_sys_exit(ftrace_syscall_exit);
359 mutex_unlock(&syscall_trace_lock);
362 struct trace_event event_syscall_enter = {
363 .trace = print_syscall_enter,
366 struct trace_event event_syscall_exit = {
367 .trace = print_syscall_exit,
370 #ifdef CONFIG_EVENT_PROFILE
372 static DECLARE_BITMAP(enabled_prof_enter_syscalls, FTRACE_SYSCALL_MAX);
373 static DECLARE_BITMAP(enabled_prof_exit_syscalls, FTRACE_SYSCALL_MAX);
374 static int sys_prof_refcount_enter;
375 static int sys_prof_refcount_exit;
377 static void prof_syscall_enter(struct pt_regs *regs, long id)
379 struct syscall_trace_enter *rec;
380 struct syscall_metadata *sys_data;
381 int syscall_nr;
382 int size;
384 syscall_nr = syscall_get_nr(current, regs);
385 if (!test_bit(syscall_nr, enabled_prof_enter_syscalls))
386 return;
388 sys_data = syscall_nr_to_meta(syscall_nr);
389 if (!sys_data)
390 return;
392 /* get the size after alignment with the u32 buffer size field */
393 size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec);
394 size = ALIGN(size + sizeof(u32), sizeof(u64));
395 size -= sizeof(u32);
397 do {
398 char raw_data[size];
400 /* zero the dead bytes from align to not leak stack to user */
401 *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
403 rec = (struct syscall_trace_enter *) raw_data;
404 tracing_generic_entry_update(&rec->ent, 0, 0);
405 rec->ent.type = sys_data->enter_id;
406 rec->nr = syscall_nr;
407 syscall_get_arguments(current, regs, 0, sys_data->nb_args,
408 (unsigned long *)&rec->args);
409 perf_tpcounter_event(sys_data->enter_id, 0, 1, rec, size);
410 } while(0);
413 int reg_prof_syscall_enter(char *name)
415 int ret = 0;
416 int num;
418 num = syscall_name_to_nr(name);
419 if (num < 0 || num >= FTRACE_SYSCALL_MAX)
420 return -ENOSYS;
422 mutex_lock(&syscall_trace_lock);
423 if (!sys_prof_refcount_enter)
424 ret = register_trace_sys_enter(prof_syscall_enter);
425 if (ret) {
426 pr_info("event trace: Could not activate"
427 "syscall entry trace point");
428 } else {
429 set_bit(num, enabled_prof_enter_syscalls);
430 sys_prof_refcount_enter++;
432 mutex_unlock(&syscall_trace_lock);
433 return ret;
436 void unreg_prof_syscall_enter(char *name)
438 int num;
440 num = syscall_name_to_nr(name);
441 if (num < 0 || num >= FTRACE_SYSCALL_MAX)
442 return;
444 mutex_lock(&syscall_trace_lock);
445 sys_prof_refcount_enter--;
446 clear_bit(num, enabled_prof_enter_syscalls);
447 if (!sys_prof_refcount_enter)
448 unregister_trace_sys_enter(prof_syscall_enter);
449 mutex_unlock(&syscall_trace_lock);
452 static void prof_syscall_exit(struct pt_regs *regs, long ret)
454 struct syscall_metadata *sys_data;
455 struct syscall_trace_exit rec;
456 int syscall_nr;
458 syscall_nr = syscall_get_nr(current, regs);
459 if (!test_bit(syscall_nr, enabled_prof_exit_syscalls))
460 return;
462 sys_data = syscall_nr_to_meta(syscall_nr);
463 if (!sys_data)
464 return;
466 tracing_generic_entry_update(&rec.ent, 0, 0);
467 rec.ent.type = sys_data->exit_id;
468 rec.nr = syscall_nr;
469 rec.ret = syscall_get_return_value(current, regs);
471 perf_tpcounter_event(sys_data->exit_id, 0, 1, &rec, sizeof(rec));
474 int reg_prof_syscall_exit(char *name)
476 int ret = 0;
477 int num;
479 num = syscall_name_to_nr(name);
480 if (num < 0 || num >= FTRACE_SYSCALL_MAX)
481 return -ENOSYS;
483 mutex_lock(&syscall_trace_lock);
484 if (!sys_prof_refcount_exit)
485 ret = register_trace_sys_exit(prof_syscall_exit);
486 if (ret) {
487 pr_info("event trace: Could not activate"
488 "syscall entry trace point");
489 } else {
490 set_bit(num, enabled_prof_exit_syscalls);
491 sys_prof_refcount_exit++;
493 mutex_unlock(&syscall_trace_lock);
494 return ret;
497 void unreg_prof_syscall_exit(char *name)
499 int num;
501 num = syscall_name_to_nr(name);
502 if (num < 0 || num >= FTRACE_SYSCALL_MAX)
503 return;
505 mutex_lock(&syscall_trace_lock);
506 sys_prof_refcount_exit--;
507 clear_bit(num, enabled_prof_exit_syscalls);
508 if (!sys_prof_refcount_exit)
509 unregister_trace_sys_exit(prof_syscall_exit);
510 mutex_unlock(&syscall_trace_lock);
513 #endif