perf: Tidy up after the big rename
[linux-2.6.git] / kernel / trace / trace_syscalls.c
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_event.h>
6 #include <asm/syscall.h>
7
8 #include "trace_output.h"
9 #include "trace.h"
10
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, NR_syscalls);
15 static DECLARE_BITMAP(enabled_exit_syscalls, NR_syscalls);
16
17 enum print_line_t
18 print_syscall_enter(struct trace_iterator *iter, int flags)
19 {
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;
25
26         trace = (typeof(trace))ent;
27         syscall = trace->nr;
28         entry = syscall_nr_to_meta(syscall);
29
30         if (!entry)
31                 goto end;
32
33         if (entry->enter_id != ent->type) {
34                 WARN_ON_ONCE(1);
35                 goto end;
36         }
37
38         ret = trace_seq_printf(s, "%s(", entry->name);
39         if (!ret)
40                 return TRACE_TYPE_PARTIAL_LINE;
41
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;
48                 }
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;
55         }
56
57         ret = trace_seq_putc(s, ')');
58         if (!ret)
59                 return TRACE_TYPE_PARTIAL_LINE;
60
61 end:
62         ret =  trace_seq_putc(s, '\n');
63         if (!ret)
64                 return TRACE_TYPE_PARTIAL_LINE;
65
66         return TRACE_TYPE_HANDLED;
67 }
68
69 enum print_line_t
70 print_syscall_exit(struct trace_iterator *iter, int flags)
71 {
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;
78
79         trace = (typeof(trace))ent;
80         syscall = trace->nr;
81         entry = syscall_nr_to_meta(syscall);
82
83         if (!entry) {
84                 trace_seq_printf(s, "\n");
85                 return TRACE_TYPE_HANDLED;
86         }
87
88         if (entry->exit_id != ent->type) {
89                 WARN_ON_ONCE(1);
90                 return TRACE_TYPE_UNHANDLED;
91         }
92
93         ret = trace_seq_printf(s, "%s -> 0x%lx\n", entry->name,
94                                 trace->ret);
95         if (!ret)
96                 return TRACE_TYPE_PARTIAL_LINE;
97
98         return TRACE_TYPE_HANDLED;
99 }
100
101 extern char *__bad_type_size(void);
102
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)
107
108 int syscall_enter_format(struct ftrace_event_call *call, struct trace_seq *s)
109 {
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);
116
117         nr = syscall_name_to_nr(call->data);
118         entry = syscall_nr_to_meta(nr);
119
120         if (!entry)
121                 return 0;
122
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;
127
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);
138         }
139
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;
147         }
148         trace_seq_putc(s, '"');
149
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;
155         }
156
157         return trace_seq_putc(s, '\n');
158 }
159
160 int syscall_exit_format(struct ftrace_event_call *call, struct trace_seq *s)
161 {
162         int ret;
163         struct syscall_trace_exit trace;
164
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;
172
173         return trace_seq_printf(s, "\nprint fmt: \"0x%%lx\", REC->ret\n");
174 }
175
176 int syscall_enter_define_fields(struct ftrace_event_call *call)
177 {
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);
184
185         nr = syscall_name_to_nr(call->data);
186         meta = syscall_nr_to_meta(nr);
187
188         if (!meta)
189                 return 0;
190
191         ret = trace_define_common_fields(call);
192         if (ret)
193                 return ret;
194
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);
201         }
202
203         return ret;
204 }
205
206 int syscall_exit_define_fields(struct ftrace_event_call *call)
207 {
208         struct syscall_trace_exit trace;
209         int ret;
210
211         ret = trace_define_common_fields(call);
212         if (ret)
213                 return ret;
214
215         ret = trace_define_field(call, SYSCALL_FIELD(unsigned long, ret), 0,
216                                  FILTER_OTHER);
217
218         return ret;
219 }
220
221 void ftrace_syscall_enter(struct pt_regs *regs, long id)
222 {
223         struct syscall_trace_enter *entry;
224         struct syscall_metadata *sys_data;
225         struct ring_buffer_event *event;
226         struct ring_buffer *buffer;
227         int size;
228         int syscall_nr;
229
230         syscall_nr = syscall_get_nr(current, regs);
231         if (syscall_nr < 0)
232                 return;
233         if (!test_bit(syscall_nr, enabled_enter_syscalls))
234                 return;
235
236         sys_data = syscall_nr_to_meta(syscall_nr);
237         if (!sys_data)
238                 return;
239
240         size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;
241
242         event = trace_current_buffer_lock_reserve(&buffer, sys_data->enter_id,
243                                                   size, 0, 0);
244         if (!event)
245                 return;
246
247         entry = ring_buffer_event_data(event);
248         entry->nr = syscall_nr;
249         syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args);
250
251         if (!filter_current_check_discard(buffer, sys_data->enter_event,
252                                           entry, event))
253                 trace_current_buffer_unlock_commit(buffer, event, 0, 0);
254 }
255
256 void ftrace_syscall_exit(struct pt_regs *regs, long ret)
257 {
258         struct syscall_trace_exit *entry;
259         struct syscall_metadata *sys_data;
260         struct ring_buffer_event *event;
261         struct ring_buffer *buffer;
262         int syscall_nr;
263
264         syscall_nr = syscall_get_nr(current, regs);
265         if (syscall_nr < 0)
266                 return;
267         if (!test_bit(syscall_nr, enabled_exit_syscalls))
268                 return;
269
270         sys_data = syscall_nr_to_meta(syscall_nr);
271         if (!sys_data)
272                 return;
273
274         event = trace_current_buffer_lock_reserve(&buffer, sys_data->exit_id,
275                                 sizeof(*entry), 0, 0);
276         if (!event)
277                 return;
278
279         entry = ring_buffer_event_data(event);
280         entry->nr = syscall_nr;
281         entry->ret = syscall_get_return_value(current, regs);
282
283         if (!filter_current_check_discard(buffer, sys_data->exit_event,
284                                           entry, event))
285                 trace_current_buffer_unlock_commit(buffer, event, 0, 0);
286 }
287
288 int reg_event_syscall_enter(void *ptr)
289 {
290         int ret = 0;
291         int num;
292         char *name;
293
294         name = (char *)ptr;
295         num = syscall_name_to_nr(name);
296         if (num < 0 || num >= NR_syscalls)
297                 return -ENOSYS;
298         mutex_lock(&syscall_trace_lock);
299         if (!sys_refcount_enter)
300                 ret = register_trace_sys_enter(ftrace_syscall_enter);
301         if (ret) {
302                 pr_info("event trace: Could not activate"
303                                 "syscall entry trace point");
304         } else {
305                 set_bit(num, enabled_enter_syscalls);
306                 sys_refcount_enter++;
307         }
308         mutex_unlock(&syscall_trace_lock);
309         return ret;
310 }
311
312 void unreg_event_syscall_enter(void *ptr)
313 {
314         int num;
315         char *name;
316
317         name = (char *)ptr;
318         num = syscall_name_to_nr(name);
319         if (num < 0 || num >= NR_syscalls)
320                 return;
321         mutex_lock(&syscall_trace_lock);
322         sys_refcount_enter--;
323         clear_bit(num, enabled_enter_syscalls);
324         if (!sys_refcount_enter)
325                 unregister_trace_sys_enter(ftrace_syscall_enter);
326         mutex_unlock(&syscall_trace_lock);
327 }
328
329 int reg_event_syscall_exit(void *ptr)
330 {
331         int ret = 0;
332         int num;
333         char *name;
334
335         name = (char *)ptr;
336         num = syscall_name_to_nr(name);
337         if (num < 0 || num >= NR_syscalls)
338                 return -ENOSYS;
339         mutex_lock(&syscall_trace_lock);
340         if (!sys_refcount_exit)
341                 ret = register_trace_sys_exit(ftrace_syscall_exit);
342         if (ret) {
343                 pr_info("event trace: Could not activate"
344                                 "syscall exit trace point");
345         } else {
346                 set_bit(num, enabled_exit_syscalls);
347                 sys_refcount_exit++;
348         }
349         mutex_unlock(&syscall_trace_lock);
350         return ret;
351 }
352
353 void unreg_event_syscall_exit(void *ptr)
354 {
355         int num;
356         char *name;
357
358         name = (char *)ptr;
359         num = syscall_name_to_nr(name);
360         if (num < 0 || num >= NR_syscalls)
361                 return;
362         mutex_lock(&syscall_trace_lock);
363         sys_refcount_exit--;
364         clear_bit(num, enabled_exit_syscalls);
365         if (!sys_refcount_exit)
366                 unregister_trace_sys_exit(ftrace_syscall_exit);
367         mutex_unlock(&syscall_trace_lock);
368 }
369
370 struct trace_event event_syscall_enter = {
371         .trace                  = print_syscall_enter,
372 };
373
374 struct trace_event event_syscall_exit = {
375         .trace                  = print_syscall_exit,
376 };
377
378 #ifdef CONFIG_EVENT_PROFILE
379
380 static DECLARE_BITMAP(enabled_prof_enter_syscalls, NR_syscalls);
381 static DECLARE_BITMAP(enabled_prof_exit_syscalls, NR_syscalls);
382 static int sys_prof_refcount_enter;
383 static int sys_prof_refcount_exit;
384
385 static void prof_syscall_enter(struct pt_regs *regs, long id)
386 {
387         struct syscall_trace_enter *rec;
388         struct syscall_metadata *sys_data;
389         int syscall_nr;
390         int size;
391
392         syscall_nr = syscall_get_nr(current, regs);
393         if (!test_bit(syscall_nr, enabled_prof_enter_syscalls))
394                 return;
395
396         sys_data = syscall_nr_to_meta(syscall_nr);
397         if (!sys_data)
398                 return;
399
400         /* get the size after alignment with the u32 buffer size field */
401         size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec);
402         size = ALIGN(size + sizeof(u32), sizeof(u64));
403         size -= sizeof(u32);
404
405         do {
406                 char raw_data[size];
407
408                 /* zero the dead bytes from align to not leak stack to user */
409                 *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
410
411                 rec = (struct syscall_trace_enter *) raw_data;
412                 tracing_generic_entry_update(&rec->ent, 0, 0);
413                 rec->ent.type = sys_data->enter_id;
414                 rec->nr = syscall_nr;
415                 syscall_get_arguments(current, regs, 0, sys_data->nb_args,
416                                        (unsigned long *)&rec->args);
417                 perf_tp_event(sys_data->enter_id, 0, 1, rec, size);
418         } while(0);
419 }
420
421 int reg_prof_syscall_enter(char *name)
422 {
423         int ret = 0;
424         int num;
425
426         num = syscall_name_to_nr(name);
427         if (num < 0 || num >= NR_syscalls)
428                 return -ENOSYS;
429
430         mutex_lock(&syscall_trace_lock);
431         if (!sys_prof_refcount_enter)
432                 ret = register_trace_sys_enter(prof_syscall_enter);
433         if (ret) {
434                 pr_info("event trace: Could not activate"
435                                 "syscall entry trace point");
436         } else {
437                 set_bit(num, enabled_prof_enter_syscalls);
438                 sys_prof_refcount_enter++;
439         }
440         mutex_unlock(&syscall_trace_lock);
441         return ret;
442 }
443
444 void unreg_prof_syscall_enter(char *name)
445 {
446         int num;
447
448         num = syscall_name_to_nr(name);
449         if (num < 0 || num >= NR_syscalls)
450                 return;
451
452         mutex_lock(&syscall_trace_lock);
453         sys_prof_refcount_enter--;
454         clear_bit(num, enabled_prof_enter_syscalls);
455         if (!sys_prof_refcount_enter)
456                 unregister_trace_sys_enter(prof_syscall_enter);
457         mutex_unlock(&syscall_trace_lock);
458 }
459
460 static void prof_syscall_exit(struct pt_regs *regs, long ret)
461 {
462         struct syscall_metadata *sys_data;
463         struct syscall_trace_exit rec;
464         int syscall_nr;
465
466         syscall_nr = syscall_get_nr(current, regs);
467         if (!test_bit(syscall_nr, enabled_prof_exit_syscalls))
468                 return;
469
470         sys_data = syscall_nr_to_meta(syscall_nr);
471         if (!sys_data)
472                 return;
473
474         tracing_generic_entry_update(&rec.ent, 0, 0);
475         rec.ent.type = sys_data->exit_id;
476         rec.nr = syscall_nr;
477         rec.ret = syscall_get_return_value(current, regs);
478
479         perf_tp_event(sys_data->exit_id, 0, 1, &rec, sizeof(rec));
480 }
481
482 int reg_prof_syscall_exit(char *name)
483 {
484         int ret = 0;
485         int num;
486
487         num = syscall_name_to_nr(name);
488         if (num < 0 || num >= NR_syscalls)
489                 return -ENOSYS;
490
491         mutex_lock(&syscall_trace_lock);
492         if (!sys_prof_refcount_exit)
493                 ret = register_trace_sys_exit(prof_syscall_exit);
494         if (ret) {
495                 pr_info("event trace: Could not activate"
496                                 "syscall entry trace point");
497         } else {
498                 set_bit(num, enabled_prof_exit_syscalls);
499                 sys_prof_refcount_exit++;
500         }
501         mutex_unlock(&syscall_trace_lock);
502         return ret;
503 }
504
505 void unreg_prof_syscall_exit(char *name)
506 {
507         int num;
508
509         num = syscall_name_to_nr(name);
510         if (num < 0 || num >= NR_syscalls)
511                 return;
512
513         mutex_lock(&syscall_trace_lock);
514         sys_prof_refcount_exit--;
515         clear_bit(num, enabled_prof_exit_syscalls);
516         if (!sys_prof_refcount_exit)
517                 unregister_trace_sys_exit(prof_syscall_exit);
518         mutex_unlock(&syscall_trace_lock);
519 }
520
521 #endif
522
523