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1#include <trace/syscall.h>
2#include <trace/events/syscalls.h>
3#include <linux/syscalls.h>
4#include <linux/slab.h>
5#include <linux/kernel.h>
6#include <linux/module.h> /* for MODULE_NAME_LEN via KSYM_SYMBOL_LEN */
7#include <linux/ftrace.h>
8#include <linux/perf_event.h>
9#include <asm/syscall.h>
10
11#include "trace_output.h"
12#include "trace.h"
13
14static DEFINE_MUTEX(syscall_trace_lock);
15
16static int syscall_enter_register(struct ftrace_event_call *event,
17 enum trace_reg type, void *data);
18static int syscall_exit_register(struct ftrace_event_call *event,
19 enum trace_reg type, void *data);
20
21static struct list_head *
22syscall_get_enter_fields(struct ftrace_event_call *call)
23{
24 struct syscall_metadata *entry = call->data;
25
26 return &entry->enter_fields;
27}
28
29extern struct syscall_metadata *__start_syscalls_metadata[];
30extern struct syscall_metadata *__stop_syscalls_metadata[];
31
32static struct syscall_metadata **syscalls_metadata;
33
34#ifndef ARCH_HAS_SYSCALL_MATCH_SYM_NAME
35static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
36{
37 /*
38 * Only compare after the "sys" prefix. Archs that use
39 * syscall wrappers may have syscalls symbols aliases prefixed
40 * with ".SyS" or ".sys" instead of "sys", leading to an unwanted
41 * mismatch.
42 */
43 return !strcmp(sym + 3, name + 3);
44}
45#endif
46
47#ifdef ARCH_TRACE_IGNORE_COMPAT_SYSCALLS
48/*
49 * Some architectures that allow for 32bit applications
50 * to run on a 64bit kernel, do not map the syscalls for
51 * the 32bit tasks the same as they do for 64bit tasks.
52 *
53 * *cough*x86*cough*
54 *
55 * In such a case, instead of reporting the wrong syscalls,
56 * simply ignore them.
57 *
58 * For an arch to ignore the compat syscalls it needs to
59 * define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS as well as
60 * define the function arch_trace_is_compat_syscall() to let
61 * the tracing system know that it should ignore it.
62 */
63static int
64trace_get_syscall_nr(struct task_struct *task, struct pt_regs *regs)
65{
66 if (unlikely(arch_trace_is_compat_syscall(regs)))
67 return -1;
68
69 return syscall_get_nr(task, regs);
70}
71#else
72static inline int
73trace_get_syscall_nr(struct task_struct *task, struct pt_regs *regs)
74{
75 return syscall_get_nr(task, regs);
76}
77#endif /* ARCH_TRACE_IGNORE_COMPAT_SYSCALLS */
78
79static __init struct syscall_metadata *
80find_syscall_meta(unsigned long syscall)
81{
82 struct syscall_metadata **start;
83 struct syscall_metadata **stop;
84 char str[KSYM_SYMBOL_LEN];
85
86
87 start = __start_syscalls_metadata;
88 stop = __stop_syscalls_metadata;
89 kallsyms_lookup(syscall, NULL, NULL, NULL, str);
90
91 if (arch_syscall_match_sym_name(str, "sys_ni_syscall"))
92 return NULL;
93
94 for ( ; start < stop; start++) {
95 if ((*start)->name && arch_syscall_match_sym_name(str, (*start)->name))
96 return *start;
97 }
98 return NULL;
99}
100
101static struct syscall_metadata *syscall_nr_to_meta(int nr)
102{
103 if (!syscalls_metadata || nr >= NR_syscalls || nr < 0)
104 return NULL;
105
106 return syscalls_metadata[nr];
107}
108
109static enum print_line_t
110print_syscall_enter(struct trace_iterator *iter, int flags,
111 struct trace_event *event)
112{
113 struct trace_seq *s = &iter->seq;
114 struct trace_entry *ent = iter->ent;
115 struct syscall_trace_enter *trace;
116 struct syscall_metadata *entry;
117 int i, ret, syscall;
118
119 trace = (typeof(trace))ent;
120 syscall = trace->nr;
121 entry = syscall_nr_to_meta(syscall);
122
123 if (!entry)
124 goto end;
125
126 if (entry->enter_event->event.type != ent->type) {
127 WARN_ON_ONCE(1);
128 goto end;
129 }
130
131 ret = trace_seq_printf(s, "%s(", entry->name);
132 if (!ret)
133 return TRACE_TYPE_PARTIAL_LINE;
134
135 for (i = 0; i < entry->nb_args; i++) {
136 /* parameter types */
137 if (trace_flags & TRACE_ITER_VERBOSE) {
138 ret = trace_seq_printf(s, "%s ", entry->types[i]);
139 if (!ret)
140 return TRACE_TYPE_PARTIAL_LINE;
141 }
142 /* parameter values */
143 ret = trace_seq_printf(s, "%s: %lx%s", entry->args[i],
144 trace->args[i],
145 i == entry->nb_args - 1 ? "" : ", ");
146 if (!ret)
147 return TRACE_TYPE_PARTIAL_LINE;
148 }
149
150 ret = trace_seq_putc(s, ')');
151 if (!ret)
152 return TRACE_TYPE_PARTIAL_LINE;
153
154end:
155 ret = trace_seq_putc(s, '\n');
156 if (!ret)
157 return TRACE_TYPE_PARTIAL_LINE;
158
159 return TRACE_TYPE_HANDLED;
160}
161
162static enum print_line_t
163print_syscall_exit(struct trace_iterator *iter, int flags,
164 struct trace_event *event)
165{
166 struct trace_seq *s = &iter->seq;
167 struct trace_entry *ent = iter->ent;
168 struct syscall_trace_exit *trace;
169 int syscall;
170 struct syscall_metadata *entry;
171 int ret;
172
173 trace = (typeof(trace))ent;
174 syscall = trace->nr;
175 entry = syscall_nr_to_meta(syscall);
176
177 if (!entry) {
178 trace_seq_putc(s, '\n');
179 return TRACE_TYPE_HANDLED;
180 }
181
182 if (entry->exit_event->event.type != ent->type) {
183 WARN_ON_ONCE(1);
184 return TRACE_TYPE_UNHANDLED;
185 }
186
187 ret = trace_seq_printf(s, "%s -> 0x%lx\n", entry->name,
188 trace->ret);
189 if (!ret)
190 return TRACE_TYPE_PARTIAL_LINE;
191
192 return TRACE_TYPE_HANDLED;
193}
194
195extern char *__bad_type_size(void);
196
197#define SYSCALL_FIELD(type, name) \
198 sizeof(type) != sizeof(trace.name) ? \
199 __bad_type_size() : \
200 #type, #name, offsetof(typeof(trace), name), \
201 sizeof(trace.name), is_signed_type(type)
202
203static int __init
204__set_enter_print_fmt(struct syscall_metadata *entry, char *buf, int len)
205{
206 int i;
207 int pos = 0;
208
209 /* When len=0, we just calculate the needed length */
210#define LEN_OR_ZERO (len ? len - pos : 0)
211
212 pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
213 for (i = 0; i < entry->nb_args; i++) {
214 pos += snprintf(buf + pos, LEN_OR_ZERO, "%s: 0x%%0%zulx%s",
215 entry->args[i], sizeof(unsigned long),
216 i == entry->nb_args - 1 ? "" : ", ");
217 }
218 pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
219
220 for (i = 0; i < entry->nb_args; i++) {
221 pos += snprintf(buf + pos, LEN_OR_ZERO,
222 ", ((unsigned long)(REC->%s))", entry->args[i]);
223 }
224
225#undef LEN_OR_ZERO
226
227 /* return the length of print_fmt */
228 return pos;
229}
230
231static int __init set_syscall_print_fmt(struct ftrace_event_call *call)
232{
233 char *print_fmt;
234 int len;
235 struct syscall_metadata *entry = call->data;
236
237 if (entry->enter_event != call) {
238 call->print_fmt = "\"0x%lx\", REC->ret";
239 return 0;
240 }
241
242 /* First: called with 0 length to calculate the needed length */
243 len = __set_enter_print_fmt(entry, NULL, 0);
244
245 print_fmt = kmalloc(len + 1, GFP_KERNEL);
246 if (!print_fmt)
247 return -ENOMEM;
248
249 /* Second: actually write the @print_fmt */
250 __set_enter_print_fmt(entry, print_fmt, len + 1);
251 call->print_fmt = print_fmt;
252
253 return 0;
254}
255
256static void __init free_syscall_print_fmt(struct ftrace_event_call *call)
257{
258 struct syscall_metadata *entry = call->data;
259
260 if (entry->enter_event == call)
261 kfree(call->print_fmt);
262}
263
264static int __init syscall_enter_define_fields(struct ftrace_event_call *call)
265{
266 struct syscall_trace_enter trace;
267 struct syscall_metadata *meta = call->data;
268 int ret;
269 int i;
270 int offset = offsetof(typeof(trace), args);
271
272 ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER);
273 if (ret)
274 return ret;
275
276 for (i = 0; i < meta->nb_args; i++) {
277 ret = trace_define_field(call, meta->types[i],
278 meta->args[i], offset,
279 sizeof(unsigned long), 0,
280 FILTER_OTHER);
281 offset += sizeof(unsigned long);
282 }
283
284 return ret;
285}
286
287static int __init syscall_exit_define_fields(struct ftrace_event_call *call)
288{
289 struct syscall_trace_exit trace;
290 int ret;
291
292 ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER);
293 if (ret)
294 return ret;
295
296 ret = trace_define_field(call, SYSCALL_FIELD(long, ret),
297 FILTER_OTHER);
298
299 return ret;
300}
301
302static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id)
303{
304 struct trace_array *tr = data;
305 struct ftrace_event_file *ftrace_file;
306 struct syscall_trace_enter *entry;
307 struct syscall_metadata *sys_data;
308 struct ring_buffer_event *event;
309 struct ring_buffer *buffer;
310 unsigned long irq_flags;
311 int pc;
312 int syscall_nr;
313 int size;
314
315 syscall_nr = trace_get_syscall_nr(current, regs);
316 if (syscall_nr < 0)
317 return;
318
319 /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE) */
320 ftrace_file = rcu_dereference_sched(tr->enter_syscall_files[syscall_nr]);
321 if (!ftrace_file)
322 return;
323
324 if (ftrace_trigger_soft_disabled(ftrace_file))
325 return;
326
327 sys_data = syscall_nr_to_meta(syscall_nr);
328 if (!sys_data)
329 return;
330
331 size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;
332
333 local_save_flags(irq_flags);
334 pc = preempt_count();
335
336 buffer = tr->trace_buffer.buffer;
337 event = trace_buffer_lock_reserve(buffer,
338 sys_data->enter_event->event.type, size, irq_flags, pc);
339 if (!event)
340 return;
341
342 entry = ring_buffer_event_data(event);
343 entry->nr = syscall_nr;
344 syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args);
345
346 event_trigger_unlock_commit(ftrace_file, buffer, event, entry,
347 irq_flags, pc);
348}
349
350static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret)
351{
352 struct trace_array *tr = data;
353 struct ftrace_event_file *ftrace_file;
354 struct syscall_trace_exit *entry;
355 struct syscall_metadata *sys_data;
356 struct ring_buffer_event *event;
357 struct ring_buffer *buffer;
358 unsigned long irq_flags;
359 int pc;
360 int syscall_nr;
361
362 syscall_nr = trace_get_syscall_nr(current, regs);
363 if (syscall_nr < 0)
364 return;
365
366 /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE()) */
367 ftrace_file = rcu_dereference_sched(tr->exit_syscall_files[syscall_nr]);
368 if (!ftrace_file)
369 return;
370
371 if (ftrace_trigger_soft_disabled(ftrace_file))
372 return;
373
374 sys_data = syscall_nr_to_meta(syscall_nr);
375 if (!sys_data)
376 return;
377
378 local_save_flags(irq_flags);
379 pc = preempt_count();
380
381 buffer = tr->trace_buffer.buffer;
382 event = trace_buffer_lock_reserve(buffer,
383 sys_data->exit_event->event.type, sizeof(*entry),
384 irq_flags, pc);
385 if (!event)
386 return;
387
388 entry = ring_buffer_event_data(event);
389 entry->nr = syscall_nr;
390 entry->ret = syscall_get_return_value(current, regs);
391
392 event_trigger_unlock_commit(ftrace_file, buffer, event, entry,
393 irq_flags, pc);
394}
395
396static int reg_event_syscall_enter(struct ftrace_event_file *file,
397 struct ftrace_event_call *call)
398{
399 struct trace_array *tr = file->tr;
400 int ret = 0;
401 int num;
402
403 num = ((struct syscall_metadata *)call->data)->syscall_nr;
404 if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
405 return -ENOSYS;
406 mutex_lock(&syscall_trace_lock);
407 if (!tr->sys_refcount_enter)
408 ret = register_trace_sys_enter(ftrace_syscall_enter, tr);
409 if (!ret) {
410 rcu_assign_pointer(tr->enter_syscall_files[num], file);
411 tr->sys_refcount_enter++;
412 }
413 mutex_unlock(&syscall_trace_lock);
414 return ret;
415}
416
417static void unreg_event_syscall_enter(struct ftrace_event_file *file,
418 struct ftrace_event_call *call)
419{
420 struct trace_array *tr = file->tr;
421 int num;
422
423 num = ((struct syscall_metadata *)call->data)->syscall_nr;
424 if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
425 return;
426 mutex_lock(&syscall_trace_lock);
427 tr->sys_refcount_enter--;
428 rcu_assign_pointer(tr->enter_syscall_files[num], NULL);
429 if (!tr->sys_refcount_enter)
430 unregister_trace_sys_enter(ftrace_syscall_enter, tr);
431 mutex_unlock(&syscall_trace_lock);
432}
433
434static int reg_event_syscall_exit(struct ftrace_event_file *file,
435 struct ftrace_event_call *call)
436{
437 struct trace_array *tr = file->tr;
438 int ret = 0;
439 int num;
440
441 num = ((struct syscall_metadata *)call->data)->syscall_nr;
442 if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
443 return -ENOSYS;
444 mutex_lock(&syscall_trace_lock);
445 if (!tr->sys_refcount_exit)
446 ret = register_trace_sys_exit(ftrace_syscall_exit, tr);
447 if (!ret) {
448 rcu_assign_pointer(tr->exit_syscall_files[num], file);
449 tr->sys_refcount_exit++;
450 }
451 mutex_unlock(&syscall_trace_lock);
452 return ret;
453}
454
455static void unreg_event_syscall_exit(struct ftrace_event_file *file,
456 struct ftrace_event_call *call)
457{
458 struct trace_array *tr = file->tr;
459 int num;
460
461 num = ((struct syscall_metadata *)call->data)->syscall_nr;
462 if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
463 return;
464 mutex_lock(&syscall_trace_lock);
465 tr->sys_refcount_exit--;
466 rcu_assign_pointer(tr->exit_syscall_files[num], NULL);
467 if (!tr->sys_refcount_exit)
468 unregister_trace_sys_exit(ftrace_syscall_exit, tr);
469 mutex_unlock(&syscall_trace_lock);
470}
471
472static int __init init_syscall_trace(struct ftrace_event_call *call)
473{
474 int id;
475 int num;
476
477 num = ((struct syscall_metadata *)call->data)->syscall_nr;
478 if (num < 0 || num >= NR_syscalls) {
479 pr_debug("syscall %s metadata not mapped, disabling ftrace event\n",
480 ((struct syscall_metadata *)call->data)->name);
481 return -ENOSYS;
482 }
483
484 if (set_syscall_print_fmt(call) < 0)
485 return -ENOMEM;
486
487 id = trace_event_raw_init(call);
488
489 if (id < 0) {
490 free_syscall_print_fmt(call);
491 return id;
492 }
493
494 return id;
495}
496
497struct trace_event_functions enter_syscall_print_funcs = {
498 .trace = print_syscall_enter,
499};
500
501struct trace_event_functions exit_syscall_print_funcs = {
502 .trace = print_syscall_exit,
503};
504
505struct ftrace_event_class __refdata event_class_syscall_enter = {
506 .system = "syscalls",
507 .reg = syscall_enter_register,
508 .define_fields = syscall_enter_define_fields,
509 .get_fields = syscall_get_enter_fields,
510 .raw_init = init_syscall_trace,
511};
512
513struct ftrace_event_class __refdata event_class_syscall_exit = {
514 .system = "syscalls",
515 .reg = syscall_exit_register,
516 .define_fields = syscall_exit_define_fields,
517 .fields = LIST_HEAD_INIT(event_class_syscall_exit.fields),
518 .raw_init = init_syscall_trace,
519};
520
521unsigned long __init __weak arch_syscall_addr(int nr)
522{
523 return (unsigned long)sys_call_table[nr];
524}
525
526static int __init init_ftrace_syscalls(void)
527{
528 struct syscall_metadata *meta;
529 unsigned long addr;
530 int i;
531
532 syscalls_metadata = kcalloc(NR_syscalls, sizeof(*syscalls_metadata),
533 GFP_KERNEL);
534 if (!syscalls_metadata) {
535 WARN_ON(1);
536 return -ENOMEM;
537 }
538
539 for (i = 0; i < NR_syscalls; i++) {
540 addr = arch_syscall_addr(i);
541 meta = find_syscall_meta(addr);
542 if (!meta)
543 continue;
544
545 meta->syscall_nr = i;
546 syscalls_metadata[i] = meta;
547 }
548
549 return 0;
550}
551early_initcall(init_ftrace_syscalls);
552
553#ifdef CONFIG_PERF_EVENTS
554
555static DECLARE_BITMAP(enabled_perf_enter_syscalls, NR_syscalls);
556static DECLARE_BITMAP(enabled_perf_exit_syscalls, NR_syscalls);
557static int sys_perf_refcount_enter;
558static int sys_perf_refcount_exit;
559
560static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id)
561{
562 struct syscall_metadata *sys_data;
563 struct syscall_trace_enter *rec;
564 struct hlist_head *head;
565 int syscall_nr;
566 int rctx;
567 int size;
568
569 syscall_nr = trace_get_syscall_nr(current, regs);
570 if (syscall_nr < 0)
571 return;
572 if (!test_bit(syscall_nr, enabled_perf_enter_syscalls))
573 return;
574
575 sys_data = syscall_nr_to_meta(syscall_nr);
576 if (!sys_data)
577 return;
578
579 head = this_cpu_ptr(sys_data->enter_event->perf_events);
580 if (hlist_empty(head))
581 return;
582
583 /* get the size after alignment with the u32 buffer size field */
584 size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec);
585 size = ALIGN(size + sizeof(u32), sizeof(u64));
586 size -= sizeof(u32);
587
588 rec = (struct syscall_trace_enter *)perf_trace_buf_prepare(size,
589 sys_data->enter_event->event.type, regs, &rctx);
590 if (!rec)
591 return;
592
593 rec->nr = syscall_nr;
594 syscall_get_arguments(current, regs, 0, sys_data->nb_args,
595 (unsigned long *)&rec->args);
596 perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL);
597}
598
599static int perf_sysenter_enable(struct ftrace_event_call *call)
600{
601 int ret = 0;
602 int num;
603
604 num = ((struct syscall_metadata *)call->data)->syscall_nr;
605
606 mutex_lock(&syscall_trace_lock);
607 if (!sys_perf_refcount_enter)
608 ret = register_trace_sys_enter(perf_syscall_enter, NULL);
609 if (ret) {
610 pr_info("event trace: Could not activate"
611 "syscall entry trace point");
612 } else {
613 set_bit(num, enabled_perf_enter_syscalls);
614 sys_perf_refcount_enter++;
615 }
616 mutex_unlock(&syscall_trace_lock);
617 return ret;
618}
619
620static void perf_sysenter_disable(struct ftrace_event_call *call)
621{
622 int num;
623
624 num = ((struct syscall_metadata *)call->data)->syscall_nr;
625
626 mutex_lock(&syscall_trace_lock);
627 sys_perf_refcount_enter--;
628 clear_bit(num, enabled_perf_enter_syscalls);
629 if (!sys_perf_refcount_enter)
630 unregister_trace_sys_enter(perf_syscall_enter, NULL);
631 mutex_unlock(&syscall_trace_lock);
632}
633
634static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
635{
636 struct syscall_metadata *sys_data;
637 struct syscall_trace_exit *rec;
638 struct hlist_head *head;
639 int syscall_nr;
640 int rctx;
641 int size;
642
643 syscall_nr = trace_get_syscall_nr(current, regs);
644 if (syscall_nr < 0)
645 return;
646 if (!test_bit(syscall_nr, enabled_perf_exit_syscalls))
647 return;
648
649 sys_data = syscall_nr_to_meta(syscall_nr);
650 if (!sys_data)
651 return;
652
653 head = this_cpu_ptr(sys_data->exit_event->perf_events);
654 if (hlist_empty(head))
655 return;
656
657 /* We can probably do that at build time */
658 size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64));
659 size -= sizeof(u32);
660
661 rec = (struct syscall_trace_exit *)perf_trace_buf_prepare(size,
662 sys_data->exit_event->event.type, regs, &rctx);
663 if (!rec)
664 return;
665
666 rec->nr = syscall_nr;
667 rec->ret = syscall_get_return_value(current, regs);
668 perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL);
669}
670
671static int perf_sysexit_enable(struct ftrace_event_call *call)
672{
673 int ret = 0;
674 int num;
675
676 num = ((struct syscall_metadata *)call->data)->syscall_nr;
677
678 mutex_lock(&syscall_trace_lock);
679 if (!sys_perf_refcount_exit)
680 ret = register_trace_sys_exit(perf_syscall_exit, NULL);
681 if (ret) {
682 pr_info("event trace: Could not activate"
683 "syscall exit trace point");
684 } else {
685 set_bit(num, enabled_perf_exit_syscalls);
686 sys_perf_refcount_exit++;
687 }
688 mutex_unlock(&syscall_trace_lock);
689 return ret;
690}
691
692static void perf_sysexit_disable(struct ftrace_event_call *call)
693{
694 int num;
695
696 num = ((struct syscall_metadata *)call->data)->syscall_nr;
697
698 mutex_lock(&syscall_trace_lock);
699 sys_perf_refcount_exit--;
700 clear_bit(num, enabled_perf_exit_syscalls);
701 if (!sys_perf_refcount_exit)
702 unregister_trace_sys_exit(perf_syscall_exit, NULL);
703 mutex_unlock(&syscall_trace_lock);
704}
705
706#endif /* CONFIG_PERF_EVENTS */
707
708static int syscall_enter_register(struct ftrace_event_call *event,
709 enum trace_reg type, void *data)
710{
711 struct ftrace_event_file *file = data;
712
713 switch (type) {
714 case TRACE_REG_REGISTER:
715 return reg_event_syscall_enter(file, event);
716 case TRACE_REG_UNREGISTER:
717 unreg_event_syscall_enter(file, event);
718 return 0;
719
720#ifdef CONFIG_PERF_EVENTS
721 case TRACE_REG_PERF_REGISTER:
722 return perf_sysenter_enable(event);
723 case TRACE_REG_PERF_UNREGISTER:
724 perf_sysenter_disable(event);
725 return 0;
726 case TRACE_REG_PERF_OPEN:
727 case TRACE_REG_PERF_CLOSE:
728 case TRACE_REG_PERF_ADD:
729 case TRACE_REG_PERF_DEL:
730 return 0;
731#endif
732 }
733 return 0;
734}
735
736static int syscall_exit_register(struct ftrace_event_call *event,
737 enum trace_reg type, void *data)
738{
739 struct ftrace_event_file *file = data;
740
741 switch (type) {
742 case TRACE_REG_REGISTER:
743 return reg_event_syscall_exit(file, event);
744 case TRACE_REG_UNREGISTER:
745 unreg_event_syscall_exit(file, event);
746 return 0;
747
748#ifdef CONFIG_PERF_EVENTS
749 case TRACE_REG_PERF_REGISTER:
750 return perf_sysexit_enable(event);
751 case TRACE_REG_PERF_UNREGISTER:
752 perf_sysexit_disable(event);
753 return 0;
754 case TRACE_REG_PERF_OPEN:
755 case TRACE_REG_PERF_CLOSE:
756 case TRACE_REG_PERF_ADD:
757 case TRACE_REG_PERF_DEL:
758 return 0;
759#endif
760 }
761 return 0;
762}
1#include <trace/syscall.h>
2#include <trace/events/syscalls.h>
3#include <linux/syscalls.h>
4#include <linux/slab.h>
5#include <linux/kernel.h>
6#include <linux/module.h> /* for MODULE_NAME_LEN via KSYM_SYMBOL_LEN */
7#include <linux/ftrace.h>
8#include <linux/perf_event.h>
9#include <asm/syscall.h>
10
11#include "trace_output.h"
12#include "trace.h"
13
14static DEFINE_MUTEX(syscall_trace_lock);
15
16static int syscall_enter_register(struct trace_event_call *event,
17 enum trace_reg type, void *data);
18static int syscall_exit_register(struct trace_event_call *event,
19 enum trace_reg type, void *data);
20
21static struct list_head *
22syscall_get_enter_fields(struct trace_event_call *call)
23{
24 struct syscall_metadata *entry = call->data;
25
26 return &entry->enter_fields;
27}
28
29extern struct syscall_metadata *__start_syscalls_metadata[];
30extern struct syscall_metadata *__stop_syscalls_metadata[];
31
32static struct syscall_metadata **syscalls_metadata;
33
34#ifndef ARCH_HAS_SYSCALL_MATCH_SYM_NAME
35static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
36{
37 /*
38 * Only compare after the "sys" prefix. Archs that use
39 * syscall wrappers may have syscalls symbols aliases prefixed
40 * with ".SyS" or ".sys" instead of "sys", leading to an unwanted
41 * mismatch.
42 */
43 return !strcmp(sym + 3, name + 3);
44}
45#endif
46
47#ifdef ARCH_TRACE_IGNORE_COMPAT_SYSCALLS
48/*
49 * Some architectures that allow for 32bit applications
50 * to run on a 64bit kernel, do not map the syscalls for
51 * the 32bit tasks the same as they do for 64bit tasks.
52 *
53 * *cough*x86*cough*
54 *
55 * In such a case, instead of reporting the wrong syscalls,
56 * simply ignore them.
57 *
58 * For an arch to ignore the compat syscalls it needs to
59 * define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS as well as
60 * define the function arch_trace_is_compat_syscall() to let
61 * the tracing system know that it should ignore it.
62 */
63static int
64trace_get_syscall_nr(struct task_struct *task, struct pt_regs *regs)
65{
66 if (unlikely(arch_trace_is_compat_syscall(regs)))
67 return -1;
68
69 return syscall_get_nr(task, regs);
70}
71#else
72static inline int
73trace_get_syscall_nr(struct task_struct *task, struct pt_regs *regs)
74{
75 return syscall_get_nr(task, regs);
76}
77#endif /* ARCH_TRACE_IGNORE_COMPAT_SYSCALLS */
78
79static __init struct syscall_metadata *
80find_syscall_meta(unsigned long syscall)
81{
82 struct syscall_metadata **start;
83 struct syscall_metadata **stop;
84 char str[KSYM_SYMBOL_LEN];
85
86
87 start = __start_syscalls_metadata;
88 stop = __stop_syscalls_metadata;
89 kallsyms_lookup(syscall, NULL, NULL, NULL, str);
90
91 if (arch_syscall_match_sym_name(str, "sys_ni_syscall"))
92 return NULL;
93
94 for ( ; start < stop; start++) {
95 if ((*start)->name && arch_syscall_match_sym_name(str, (*start)->name))
96 return *start;
97 }
98 return NULL;
99}
100
101static struct syscall_metadata *syscall_nr_to_meta(int nr)
102{
103 if (!syscalls_metadata || nr >= NR_syscalls || nr < 0)
104 return NULL;
105
106 return syscalls_metadata[nr];
107}
108
109const char *get_syscall_name(int syscall)
110{
111 struct syscall_metadata *entry;
112
113 entry = syscall_nr_to_meta(syscall);
114 if (!entry)
115 return NULL;
116
117 return entry->name;
118}
119
120static enum print_line_t
121print_syscall_enter(struct trace_iterator *iter, int flags,
122 struct trace_event *event)
123{
124 struct trace_array *tr = iter->tr;
125 struct trace_seq *s = &iter->seq;
126 struct trace_entry *ent = iter->ent;
127 struct syscall_trace_enter *trace;
128 struct syscall_metadata *entry;
129 int i, syscall;
130
131 trace = (typeof(trace))ent;
132 syscall = trace->nr;
133 entry = syscall_nr_to_meta(syscall);
134
135 if (!entry)
136 goto end;
137
138 if (entry->enter_event->event.type != ent->type) {
139 WARN_ON_ONCE(1);
140 goto end;
141 }
142
143 trace_seq_printf(s, "%s(", entry->name);
144
145 for (i = 0; i < entry->nb_args; i++) {
146
147 if (trace_seq_has_overflowed(s))
148 goto end;
149
150 /* parameter types */
151 if (tr->trace_flags & TRACE_ITER_VERBOSE)
152 trace_seq_printf(s, "%s ", entry->types[i]);
153
154 /* parameter values */
155 trace_seq_printf(s, "%s: %lx%s", entry->args[i],
156 trace->args[i],
157 i == entry->nb_args - 1 ? "" : ", ");
158 }
159
160 trace_seq_putc(s, ')');
161end:
162 trace_seq_putc(s, '\n');
163
164 return trace_handle_return(s);
165}
166
167static enum print_line_t
168print_syscall_exit(struct trace_iterator *iter, int flags,
169 struct trace_event *event)
170{
171 struct trace_seq *s = &iter->seq;
172 struct trace_entry *ent = iter->ent;
173 struct syscall_trace_exit *trace;
174 int syscall;
175 struct syscall_metadata *entry;
176
177 trace = (typeof(trace))ent;
178 syscall = trace->nr;
179 entry = syscall_nr_to_meta(syscall);
180
181 if (!entry) {
182 trace_seq_putc(s, '\n');
183 goto out;
184 }
185
186 if (entry->exit_event->event.type != ent->type) {
187 WARN_ON_ONCE(1);
188 return TRACE_TYPE_UNHANDLED;
189 }
190
191 trace_seq_printf(s, "%s -> 0x%lx\n", entry->name,
192 trace->ret);
193
194 out:
195 return trace_handle_return(s);
196}
197
198extern char *__bad_type_size(void);
199
200#define SYSCALL_FIELD(type, field, name) \
201 sizeof(type) != sizeof(trace.field) ? \
202 __bad_type_size() : \
203 #type, #name, offsetof(typeof(trace), field), \
204 sizeof(trace.field), is_signed_type(type)
205
206static int __init
207__set_enter_print_fmt(struct syscall_metadata *entry, char *buf, int len)
208{
209 int i;
210 int pos = 0;
211
212 /* When len=0, we just calculate the needed length */
213#define LEN_OR_ZERO (len ? len - pos : 0)
214
215 pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
216 for (i = 0; i < entry->nb_args; i++) {
217 pos += snprintf(buf + pos, LEN_OR_ZERO, "%s: 0x%%0%zulx%s",
218 entry->args[i], sizeof(unsigned long),
219 i == entry->nb_args - 1 ? "" : ", ");
220 }
221 pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
222
223 for (i = 0; i < entry->nb_args; i++) {
224 pos += snprintf(buf + pos, LEN_OR_ZERO,
225 ", ((unsigned long)(REC->%s))", entry->args[i]);
226 }
227
228#undef LEN_OR_ZERO
229
230 /* return the length of print_fmt */
231 return pos;
232}
233
234static int __init set_syscall_print_fmt(struct trace_event_call *call)
235{
236 char *print_fmt;
237 int len;
238 struct syscall_metadata *entry = call->data;
239
240 if (entry->enter_event != call) {
241 call->print_fmt = "\"0x%lx\", REC->ret";
242 return 0;
243 }
244
245 /* First: called with 0 length to calculate the needed length */
246 len = __set_enter_print_fmt(entry, NULL, 0);
247
248 print_fmt = kmalloc(len + 1, GFP_KERNEL);
249 if (!print_fmt)
250 return -ENOMEM;
251
252 /* Second: actually write the @print_fmt */
253 __set_enter_print_fmt(entry, print_fmt, len + 1);
254 call->print_fmt = print_fmt;
255
256 return 0;
257}
258
259static void __init free_syscall_print_fmt(struct trace_event_call *call)
260{
261 struct syscall_metadata *entry = call->data;
262
263 if (entry->enter_event == call)
264 kfree(call->print_fmt);
265}
266
267static int __init syscall_enter_define_fields(struct trace_event_call *call)
268{
269 struct syscall_trace_enter trace;
270 struct syscall_metadata *meta = call->data;
271 int ret;
272 int i;
273 int offset = offsetof(typeof(trace), args);
274
275 ret = trace_define_field(call, SYSCALL_FIELD(int, nr, __syscall_nr),
276 FILTER_OTHER);
277 if (ret)
278 return ret;
279
280 for (i = 0; i < meta->nb_args; i++) {
281 ret = trace_define_field(call, meta->types[i],
282 meta->args[i], offset,
283 sizeof(unsigned long), 0,
284 FILTER_OTHER);
285 offset += sizeof(unsigned long);
286 }
287
288 return ret;
289}
290
291static int __init syscall_exit_define_fields(struct trace_event_call *call)
292{
293 struct syscall_trace_exit trace;
294 int ret;
295
296 ret = trace_define_field(call, SYSCALL_FIELD(int, nr, __syscall_nr),
297 FILTER_OTHER);
298 if (ret)
299 return ret;
300
301 ret = trace_define_field(call, SYSCALL_FIELD(long, ret, ret),
302 FILTER_OTHER);
303
304 return ret;
305}
306
307static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id)
308{
309 struct trace_array *tr = data;
310 struct trace_event_file *trace_file;
311 struct syscall_trace_enter *entry;
312 struct syscall_metadata *sys_data;
313 struct ring_buffer_event *event;
314 struct ring_buffer *buffer;
315 unsigned long irq_flags;
316 int pc;
317 int syscall_nr;
318 int size;
319
320 syscall_nr = trace_get_syscall_nr(current, regs);
321 if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
322 return;
323
324 /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE) */
325 trace_file = rcu_dereference_sched(tr->enter_syscall_files[syscall_nr]);
326 if (!trace_file)
327 return;
328
329 if (trace_trigger_soft_disabled(trace_file))
330 return;
331
332 sys_data = syscall_nr_to_meta(syscall_nr);
333 if (!sys_data)
334 return;
335
336 size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;
337
338 local_save_flags(irq_flags);
339 pc = preempt_count();
340
341 buffer = tr->trace_buffer.buffer;
342 event = trace_buffer_lock_reserve(buffer,
343 sys_data->enter_event->event.type, size, irq_flags, pc);
344 if (!event)
345 return;
346
347 entry = ring_buffer_event_data(event);
348 entry->nr = syscall_nr;
349 syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args);
350
351 event_trigger_unlock_commit(trace_file, buffer, event, entry,
352 irq_flags, pc);
353}
354
355static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret)
356{
357 struct trace_array *tr = data;
358 struct trace_event_file *trace_file;
359 struct syscall_trace_exit *entry;
360 struct syscall_metadata *sys_data;
361 struct ring_buffer_event *event;
362 struct ring_buffer *buffer;
363 unsigned long irq_flags;
364 int pc;
365 int syscall_nr;
366
367 syscall_nr = trace_get_syscall_nr(current, regs);
368 if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
369 return;
370
371 /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE()) */
372 trace_file = rcu_dereference_sched(tr->exit_syscall_files[syscall_nr]);
373 if (!trace_file)
374 return;
375
376 if (trace_trigger_soft_disabled(trace_file))
377 return;
378
379 sys_data = syscall_nr_to_meta(syscall_nr);
380 if (!sys_data)
381 return;
382
383 local_save_flags(irq_flags);
384 pc = preempt_count();
385
386 buffer = tr->trace_buffer.buffer;
387 event = trace_buffer_lock_reserve(buffer,
388 sys_data->exit_event->event.type, sizeof(*entry),
389 irq_flags, pc);
390 if (!event)
391 return;
392
393 entry = ring_buffer_event_data(event);
394 entry->nr = syscall_nr;
395 entry->ret = syscall_get_return_value(current, regs);
396
397 event_trigger_unlock_commit(trace_file, buffer, event, entry,
398 irq_flags, pc);
399}
400
401static int reg_event_syscall_enter(struct trace_event_file *file,
402 struct trace_event_call *call)
403{
404 struct trace_array *tr = file->tr;
405 int ret = 0;
406 int num;
407
408 num = ((struct syscall_metadata *)call->data)->syscall_nr;
409 if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
410 return -ENOSYS;
411 mutex_lock(&syscall_trace_lock);
412 if (!tr->sys_refcount_enter)
413 ret = register_trace_sys_enter(ftrace_syscall_enter, tr);
414 if (!ret) {
415 rcu_assign_pointer(tr->enter_syscall_files[num], file);
416 tr->sys_refcount_enter++;
417 }
418 mutex_unlock(&syscall_trace_lock);
419 return ret;
420}
421
422static void unreg_event_syscall_enter(struct trace_event_file *file,
423 struct trace_event_call *call)
424{
425 struct trace_array *tr = file->tr;
426 int num;
427
428 num = ((struct syscall_metadata *)call->data)->syscall_nr;
429 if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
430 return;
431 mutex_lock(&syscall_trace_lock);
432 tr->sys_refcount_enter--;
433 RCU_INIT_POINTER(tr->enter_syscall_files[num], NULL);
434 if (!tr->sys_refcount_enter)
435 unregister_trace_sys_enter(ftrace_syscall_enter, tr);
436 mutex_unlock(&syscall_trace_lock);
437}
438
439static int reg_event_syscall_exit(struct trace_event_file *file,
440 struct trace_event_call *call)
441{
442 struct trace_array *tr = file->tr;
443 int ret = 0;
444 int num;
445
446 num = ((struct syscall_metadata *)call->data)->syscall_nr;
447 if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
448 return -ENOSYS;
449 mutex_lock(&syscall_trace_lock);
450 if (!tr->sys_refcount_exit)
451 ret = register_trace_sys_exit(ftrace_syscall_exit, tr);
452 if (!ret) {
453 rcu_assign_pointer(tr->exit_syscall_files[num], file);
454 tr->sys_refcount_exit++;
455 }
456 mutex_unlock(&syscall_trace_lock);
457 return ret;
458}
459
460static void unreg_event_syscall_exit(struct trace_event_file *file,
461 struct trace_event_call *call)
462{
463 struct trace_array *tr = file->tr;
464 int num;
465
466 num = ((struct syscall_metadata *)call->data)->syscall_nr;
467 if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
468 return;
469 mutex_lock(&syscall_trace_lock);
470 tr->sys_refcount_exit--;
471 RCU_INIT_POINTER(tr->exit_syscall_files[num], NULL);
472 if (!tr->sys_refcount_exit)
473 unregister_trace_sys_exit(ftrace_syscall_exit, tr);
474 mutex_unlock(&syscall_trace_lock);
475}
476
477static int __init init_syscall_trace(struct trace_event_call *call)
478{
479 int id;
480 int num;
481
482 num = ((struct syscall_metadata *)call->data)->syscall_nr;
483 if (num < 0 || num >= NR_syscalls) {
484 pr_debug("syscall %s metadata not mapped, disabling ftrace event\n",
485 ((struct syscall_metadata *)call->data)->name);
486 return -ENOSYS;
487 }
488
489 if (set_syscall_print_fmt(call) < 0)
490 return -ENOMEM;
491
492 id = trace_event_raw_init(call);
493
494 if (id < 0) {
495 free_syscall_print_fmt(call);
496 return id;
497 }
498
499 return id;
500}
501
502struct trace_event_functions enter_syscall_print_funcs = {
503 .trace = print_syscall_enter,
504};
505
506struct trace_event_functions exit_syscall_print_funcs = {
507 .trace = print_syscall_exit,
508};
509
510struct trace_event_class __refdata event_class_syscall_enter = {
511 .system = "syscalls",
512 .reg = syscall_enter_register,
513 .define_fields = syscall_enter_define_fields,
514 .get_fields = syscall_get_enter_fields,
515 .raw_init = init_syscall_trace,
516};
517
518struct trace_event_class __refdata event_class_syscall_exit = {
519 .system = "syscalls",
520 .reg = syscall_exit_register,
521 .define_fields = syscall_exit_define_fields,
522 .fields = LIST_HEAD_INIT(event_class_syscall_exit.fields),
523 .raw_init = init_syscall_trace,
524};
525
526unsigned long __init __weak arch_syscall_addr(int nr)
527{
528 return (unsigned long)sys_call_table[nr];
529}
530
531void __init init_ftrace_syscalls(void)
532{
533 struct syscall_metadata *meta;
534 unsigned long addr;
535 int i;
536
537 syscalls_metadata = kcalloc(NR_syscalls, sizeof(*syscalls_metadata),
538 GFP_KERNEL);
539 if (!syscalls_metadata) {
540 WARN_ON(1);
541 return;
542 }
543
544 for (i = 0; i < NR_syscalls; i++) {
545 addr = arch_syscall_addr(i);
546 meta = find_syscall_meta(addr);
547 if (!meta)
548 continue;
549
550 meta->syscall_nr = i;
551 syscalls_metadata[i] = meta;
552 }
553}
554
555#ifdef CONFIG_PERF_EVENTS
556
557static DECLARE_BITMAP(enabled_perf_enter_syscalls, NR_syscalls);
558static DECLARE_BITMAP(enabled_perf_exit_syscalls, NR_syscalls);
559static int sys_perf_refcount_enter;
560static int sys_perf_refcount_exit;
561
562static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id)
563{
564 struct syscall_metadata *sys_data;
565 struct syscall_trace_enter *rec;
566 struct hlist_head *head;
567 int syscall_nr;
568 int rctx;
569 int size;
570
571 syscall_nr = trace_get_syscall_nr(current, regs);
572 if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
573 return;
574 if (!test_bit(syscall_nr, enabled_perf_enter_syscalls))
575 return;
576
577 sys_data = syscall_nr_to_meta(syscall_nr);
578 if (!sys_data)
579 return;
580
581 head = this_cpu_ptr(sys_data->enter_event->perf_events);
582 if (hlist_empty(head))
583 return;
584
585 /* get the size after alignment with the u32 buffer size field */
586 size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec);
587 size = ALIGN(size + sizeof(u32), sizeof(u64));
588 size -= sizeof(u32);
589
590 rec = (struct syscall_trace_enter *)perf_trace_buf_prepare(size,
591 sys_data->enter_event->event.type, NULL, &rctx);
592 if (!rec)
593 return;
594
595 rec->nr = syscall_nr;
596 syscall_get_arguments(current, regs, 0, sys_data->nb_args,
597 (unsigned long *)&rec->args);
598 perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL);
599}
600
601static int perf_sysenter_enable(struct trace_event_call *call)
602{
603 int ret = 0;
604 int num;
605
606 num = ((struct syscall_metadata *)call->data)->syscall_nr;
607
608 mutex_lock(&syscall_trace_lock);
609 if (!sys_perf_refcount_enter)
610 ret = register_trace_sys_enter(perf_syscall_enter, NULL);
611 if (ret) {
612 pr_info("event trace: Could not activate"
613 "syscall entry trace point");
614 } else {
615 set_bit(num, enabled_perf_enter_syscalls);
616 sys_perf_refcount_enter++;
617 }
618 mutex_unlock(&syscall_trace_lock);
619 return ret;
620}
621
622static void perf_sysenter_disable(struct trace_event_call *call)
623{
624 int num;
625
626 num = ((struct syscall_metadata *)call->data)->syscall_nr;
627
628 mutex_lock(&syscall_trace_lock);
629 sys_perf_refcount_enter--;
630 clear_bit(num, enabled_perf_enter_syscalls);
631 if (!sys_perf_refcount_enter)
632 unregister_trace_sys_enter(perf_syscall_enter, NULL);
633 mutex_unlock(&syscall_trace_lock);
634}
635
636static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
637{
638 struct syscall_metadata *sys_data;
639 struct syscall_trace_exit *rec;
640 struct hlist_head *head;
641 int syscall_nr;
642 int rctx;
643 int size;
644
645 syscall_nr = trace_get_syscall_nr(current, regs);
646 if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
647 return;
648 if (!test_bit(syscall_nr, enabled_perf_exit_syscalls))
649 return;
650
651 sys_data = syscall_nr_to_meta(syscall_nr);
652 if (!sys_data)
653 return;
654
655 head = this_cpu_ptr(sys_data->exit_event->perf_events);
656 if (hlist_empty(head))
657 return;
658
659 /* We can probably do that at build time */
660 size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64));
661 size -= sizeof(u32);
662
663 rec = (struct syscall_trace_exit *)perf_trace_buf_prepare(size,
664 sys_data->exit_event->event.type, NULL, &rctx);
665 if (!rec)
666 return;
667
668 rec->nr = syscall_nr;
669 rec->ret = syscall_get_return_value(current, regs);
670 perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL);
671}
672
673static int perf_sysexit_enable(struct trace_event_call *call)
674{
675 int ret = 0;
676 int num;
677
678 num = ((struct syscall_metadata *)call->data)->syscall_nr;
679
680 mutex_lock(&syscall_trace_lock);
681 if (!sys_perf_refcount_exit)
682 ret = register_trace_sys_exit(perf_syscall_exit, NULL);
683 if (ret) {
684 pr_info("event trace: Could not activate"
685 "syscall exit trace point");
686 } else {
687 set_bit(num, enabled_perf_exit_syscalls);
688 sys_perf_refcount_exit++;
689 }
690 mutex_unlock(&syscall_trace_lock);
691 return ret;
692}
693
694static void perf_sysexit_disable(struct trace_event_call *call)
695{
696 int num;
697
698 num = ((struct syscall_metadata *)call->data)->syscall_nr;
699
700 mutex_lock(&syscall_trace_lock);
701 sys_perf_refcount_exit--;
702 clear_bit(num, enabled_perf_exit_syscalls);
703 if (!sys_perf_refcount_exit)
704 unregister_trace_sys_exit(perf_syscall_exit, NULL);
705 mutex_unlock(&syscall_trace_lock);
706}
707
708#endif /* CONFIG_PERF_EVENTS */
709
710static int syscall_enter_register(struct trace_event_call *event,
711 enum trace_reg type, void *data)
712{
713 struct trace_event_file *file = data;
714
715 switch (type) {
716 case TRACE_REG_REGISTER:
717 return reg_event_syscall_enter(file, event);
718 case TRACE_REG_UNREGISTER:
719 unreg_event_syscall_enter(file, event);
720 return 0;
721
722#ifdef CONFIG_PERF_EVENTS
723 case TRACE_REG_PERF_REGISTER:
724 return perf_sysenter_enable(event);
725 case TRACE_REG_PERF_UNREGISTER:
726 perf_sysenter_disable(event);
727 return 0;
728 case TRACE_REG_PERF_OPEN:
729 case TRACE_REG_PERF_CLOSE:
730 case TRACE_REG_PERF_ADD:
731 case TRACE_REG_PERF_DEL:
732 return 0;
733#endif
734 }
735 return 0;
736}
737
738static int syscall_exit_register(struct trace_event_call *event,
739 enum trace_reg type, void *data)
740{
741 struct trace_event_file *file = data;
742
743 switch (type) {
744 case TRACE_REG_REGISTER:
745 return reg_event_syscall_exit(file, event);
746 case TRACE_REG_UNREGISTER:
747 unreg_event_syscall_exit(file, event);
748 return 0;
749
750#ifdef CONFIG_PERF_EVENTS
751 case TRACE_REG_PERF_REGISTER:
752 return perf_sysexit_enable(event);
753 case TRACE_REG_PERF_UNREGISTER:
754 perf_sysexit_disable(event);
755 return 0;
756 case TRACE_REG_PERF_OPEN:
757 case TRACE_REG_PERF_CLOSE:
758 case TRACE_REG_PERF_ADD:
759 case TRACE_REG_PERF_DEL:
760 return 0;
761#endif
762 }
763 return 0;
764}