4 * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
6 * - Added format output of fields of the trace point.
7 * This was based off of work by Tom Zanussi <tzanussi@gmail.com>.
11 #define pr_fmt(fmt) fmt
13 #include <linux/workqueue.h>
14 #include <linux/spinlock.h>
15 #include <linux/kthread.h>
16 #include <linux/tracefs.h>
17 #include <linux/uaccess.h>
18 #include <linux/bsearch.h>
19 #include <linux/module.h>
20 #include <linux/ctype.h>
21 #include <linux/sort.h>
22 #include <linux/slab.h>
23 #include <linux/delay.h>
25 #include <trace/events/sched.h>
27 #include <asm/setup.h>
29 #include "trace_output.h"
32 #define TRACE_SYSTEM "TRACE_SYSTEM"
34 DEFINE_MUTEX(event_mutex);
36 LIST_HEAD(ftrace_events);
37 static LIST_HEAD(ftrace_generic_fields);
38 static LIST_HEAD(ftrace_common_fields);
40 #define GFP_TRACE (GFP_KERNEL | __GFP_ZERO)
42 static struct kmem_cache *field_cachep;
43 static struct kmem_cache *file_cachep;
45 static inline int system_refcount(struct event_subsystem *system)
47 return system->ref_count;
50 static int system_refcount_inc(struct event_subsystem *system)
52 return system->ref_count++;
55 static int system_refcount_dec(struct event_subsystem *system)
57 return --system->ref_count;
60 /* Double loops, do not use break, only goto's work */
61 #define do_for_each_event_file(tr, file) \
62 list_for_each_entry(tr, &ftrace_trace_arrays, list) { \
63 list_for_each_entry(file, &tr->events, list)
65 #define do_for_each_event_file_safe(tr, file) \
66 list_for_each_entry(tr, &ftrace_trace_arrays, list) { \
67 struct trace_event_file *___n; \
68 list_for_each_entry_safe(file, ___n, &tr->events, list)
70 #define while_for_each_event_file() \
73 static struct list_head *
74 trace_get_fields(struct trace_event_call *event_call)
76 if (!event_call->class->get_fields)
77 return &event_call->class->fields;
78 return event_call->class->get_fields(event_call);
81 static struct ftrace_event_field *
82 __find_event_field(struct list_head *head, char *name)
84 struct ftrace_event_field *field;
86 list_for_each_entry(field, head, link) {
87 if (!strcmp(field->name, name))
94 struct ftrace_event_field *
95 trace_find_event_field(struct trace_event_call *call, char *name)
97 struct ftrace_event_field *field;
98 struct list_head *head;
100 field = __find_event_field(&ftrace_generic_fields, name);
104 field = __find_event_field(&ftrace_common_fields, name);
108 head = trace_get_fields(call);
109 return __find_event_field(head, name);
112 static int __trace_define_field(struct list_head *head, const char *type,
113 const char *name, int offset, int size,
114 int is_signed, int filter_type)
116 struct ftrace_event_field *field;
118 field = kmem_cache_alloc(field_cachep, GFP_TRACE);
125 if (filter_type == FILTER_OTHER)
126 field->filter_type = filter_assign_type(type);
128 field->filter_type = filter_type;
130 field->offset = offset;
132 field->is_signed = is_signed;
134 list_add(&field->link, head);
139 int trace_define_field(struct trace_event_call *call, const char *type,
140 const char *name, int offset, int size, int is_signed,
143 struct list_head *head;
145 if (WARN_ON(!call->class))
148 head = trace_get_fields(call);
149 return __trace_define_field(head, type, name, offset, size,
150 is_signed, filter_type);
152 EXPORT_SYMBOL_GPL(trace_define_field);
154 #define __generic_field(type, item, filter_type) \
155 ret = __trace_define_field(&ftrace_generic_fields, #type, \
156 #item, 0, 0, is_signed_type(type), \
161 #define __common_field(type, item) \
162 ret = __trace_define_field(&ftrace_common_fields, #type, \
164 offsetof(typeof(ent), item), \
166 is_signed_type(type), FILTER_OTHER); \
170 static int trace_define_generic_fields(void)
174 __generic_field(int, cpu, FILTER_OTHER);
175 __generic_field(char *, comm, FILTER_PTR_STRING);
180 static int trace_define_common_fields(void)
183 struct trace_entry ent;
185 __common_field(unsigned short, type);
186 __common_field(unsigned char, flags);
187 __common_field(unsigned char, preempt_count);
188 __common_field(int, pid);
193 static void trace_destroy_fields(struct trace_event_call *call)
195 struct ftrace_event_field *field, *next;
196 struct list_head *head;
198 head = trace_get_fields(call);
199 list_for_each_entry_safe(field, next, head, link) {
200 list_del(&field->link);
201 kmem_cache_free(field_cachep, field);
205 int trace_event_raw_init(struct trace_event_call *call)
209 id = register_trace_event(&call->event);
215 EXPORT_SYMBOL_GPL(trace_event_raw_init);
217 bool trace_event_ignore_this_pid(struct trace_event_file *trace_file)
219 struct trace_array *tr = trace_file->tr;
220 struct trace_array_cpu *data;
221 struct trace_pid_list *pid_list;
223 pid_list = rcu_dereference_sched(tr->filtered_pids);
227 data = this_cpu_ptr(tr->trace_buffer.data);
229 return data->ignore_pid;
231 EXPORT_SYMBOL_GPL(trace_event_ignore_this_pid);
233 void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer,
234 struct trace_event_file *trace_file,
237 struct trace_event_call *event_call = trace_file->event_call;
239 if ((trace_file->flags & EVENT_FILE_FL_PID_FILTER) &&
240 trace_event_ignore_this_pid(trace_file))
243 local_save_flags(fbuffer->flags);
244 fbuffer->pc = preempt_count();
245 fbuffer->trace_file = trace_file;
248 trace_event_buffer_lock_reserve(&fbuffer->buffer, trace_file,
249 event_call->event.type, len,
250 fbuffer->flags, fbuffer->pc);
254 fbuffer->entry = ring_buffer_event_data(fbuffer->event);
255 return fbuffer->entry;
257 EXPORT_SYMBOL_GPL(trace_event_buffer_reserve);
259 static DEFINE_SPINLOCK(tracepoint_iter_lock);
261 static void output_printk(struct trace_event_buffer *fbuffer)
263 struct trace_event_call *event_call;
264 struct trace_event *event;
266 struct trace_iterator *iter = tracepoint_print_iter;
271 event_call = fbuffer->trace_file->event_call;
272 if (!event_call || !event_call->event.funcs ||
273 !event_call->event.funcs->trace)
276 event = &fbuffer->trace_file->event_call->event;
278 spin_lock_irqsave(&tracepoint_iter_lock, flags);
279 trace_seq_init(&iter->seq);
280 iter->ent = fbuffer->entry;
281 event_call->event.funcs->trace(iter, 0, event);
282 trace_seq_putc(&iter->seq, 0);
283 printk("%s", iter->seq.buffer);
285 spin_unlock_irqrestore(&tracepoint_iter_lock, flags);
288 void trace_event_buffer_commit(struct trace_event_buffer *fbuffer)
290 if (tracepoint_printk)
291 output_printk(fbuffer);
293 event_trigger_unlock_commit(fbuffer->trace_file, fbuffer->buffer,
294 fbuffer->event, fbuffer->entry,
295 fbuffer->flags, fbuffer->pc);
297 EXPORT_SYMBOL_GPL(trace_event_buffer_commit);
299 int trace_event_reg(struct trace_event_call *call,
300 enum trace_reg type, void *data)
302 struct trace_event_file *file = data;
304 WARN_ON(!(call->flags & TRACE_EVENT_FL_TRACEPOINT));
306 case TRACE_REG_REGISTER:
307 return tracepoint_probe_register(call->tp,
310 case TRACE_REG_UNREGISTER:
311 tracepoint_probe_unregister(call->tp,
316 #ifdef CONFIG_PERF_EVENTS
317 case TRACE_REG_PERF_REGISTER:
318 return tracepoint_probe_register(call->tp,
319 call->class->perf_probe,
321 case TRACE_REG_PERF_UNREGISTER:
322 tracepoint_probe_unregister(call->tp,
323 call->class->perf_probe,
326 case TRACE_REG_PERF_OPEN:
327 case TRACE_REG_PERF_CLOSE:
328 case TRACE_REG_PERF_ADD:
329 case TRACE_REG_PERF_DEL:
335 EXPORT_SYMBOL_GPL(trace_event_reg);
337 void trace_event_enable_cmd_record(bool enable)
339 struct trace_event_file *file;
340 struct trace_array *tr;
342 mutex_lock(&event_mutex);
343 do_for_each_event_file(tr, file) {
345 if (!(file->flags & EVENT_FILE_FL_ENABLED))
349 tracing_start_cmdline_record();
350 set_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags);
352 tracing_stop_cmdline_record();
353 clear_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags);
355 } while_for_each_event_file();
356 mutex_unlock(&event_mutex);
359 static int __ftrace_event_enable_disable(struct trace_event_file *file,
360 int enable, int soft_disable)
362 struct trace_event_call *call = file->event_call;
363 struct trace_array *tr = file->tr;
370 * When soft_disable is set and enable is cleared, the sm_ref
371 * reference counter is decremented. If it reaches 0, we want
372 * to clear the SOFT_DISABLED flag but leave the event in the
373 * state that it was. That is, if the event was enabled and
374 * SOFT_DISABLED isn't set, then do nothing. But if SOFT_DISABLED
375 * is set we do not want the event to be enabled before we
378 * When soft_disable is not set but the SOFT_MODE flag is,
379 * we do nothing. Do not disable the tracepoint, otherwise
380 * "soft enable"s (clearing the SOFT_DISABLED bit) wont work.
383 if (atomic_dec_return(&file->sm_ref) > 0)
385 disable = file->flags & EVENT_FILE_FL_SOFT_DISABLED;
386 clear_bit(EVENT_FILE_FL_SOFT_MODE_BIT, &file->flags);
388 disable = !(file->flags & EVENT_FILE_FL_SOFT_MODE);
390 if (disable && (file->flags & EVENT_FILE_FL_ENABLED)) {
391 clear_bit(EVENT_FILE_FL_ENABLED_BIT, &file->flags);
392 if (file->flags & EVENT_FILE_FL_RECORDED_CMD) {
393 tracing_stop_cmdline_record();
394 clear_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags);
396 call->class->reg(call, TRACE_REG_UNREGISTER, file);
398 /* If in SOFT_MODE, just set the SOFT_DISABLE_BIT, else clear it */
399 if (file->flags & EVENT_FILE_FL_SOFT_MODE)
400 set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags);
402 clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags);
406 * When soft_disable is set and enable is set, we want to
407 * register the tracepoint for the event, but leave the event
408 * as is. That means, if the event was already enabled, we do
409 * nothing (but set SOFT_MODE). If the event is disabled, we
410 * set SOFT_DISABLED before enabling the event tracepoint, so
411 * it still seems to be disabled.
414 clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags);
416 if (atomic_inc_return(&file->sm_ref) > 1)
418 set_bit(EVENT_FILE_FL_SOFT_MODE_BIT, &file->flags);
421 if (!(file->flags & EVENT_FILE_FL_ENABLED)) {
423 /* Keep the event disabled, when going to SOFT_MODE. */
425 set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags);
427 if (tr->trace_flags & TRACE_ITER_RECORD_CMD) {
428 tracing_start_cmdline_record();
429 set_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags);
431 ret = call->class->reg(call, TRACE_REG_REGISTER, file);
433 tracing_stop_cmdline_record();
434 pr_info("event trace: Could not enable event "
435 "%s\n", trace_event_name(call));
438 set_bit(EVENT_FILE_FL_ENABLED_BIT, &file->flags);
440 /* WAS_ENABLED gets set but never cleared. */
441 call->flags |= TRACE_EVENT_FL_WAS_ENABLED;
449 int trace_event_enable_disable(struct trace_event_file *file,
450 int enable, int soft_disable)
452 return __ftrace_event_enable_disable(file, enable, soft_disable);
455 static int ftrace_event_enable_disable(struct trace_event_file *file,
458 return __ftrace_event_enable_disable(file, enable, 0);
461 static void ftrace_clear_events(struct trace_array *tr)
463 struct trace_event_file *file;
465 mutex_lock(&event_mutex);
466 list_for_each_entry(file, &tr->events, list) {
467 ftrace_event_enable_disable(file, 0);
469 mutex_unlock(&event_mutex);
472 static int cmp_pid(const void *key, const void *elt)
474 const pid_t *search_pid = key;
475 const pid_t *pid = elt;
477 if (*search_pid == *pid)
479 if (*search_pid < *pid)
485 check_ignore_pid(struct trace_pid_list *filtered_pids, struct task_struct *task)
491 * Return false, because if filtered_pids does not exist,
492 * all pids are good to trace.
497 search_pid = task->pid;
499 pid = bsearch(&search_pid, filtered_pids->pids,
500 filtered_pids->nr_pids, sizeof(pid_t),
509 event_filter_pid_sched_switch_probe_pre(void *data,
510 struct task_struct *prev, struct task_struct *next)
512 struct trace_array *tr = data;
513 struct trace_pid_list *pid_list;
515 pid_list = rcu_dereference_sched(tr->filtered_pids);
517 this_cpu_write(tr->trace_buffer.data->ignore_pid,
518 check_ignore_pid(pid_list, prev) &&
519 check_ignore_pid(pid_list, next));
523 event_filter_pid_sched_switch_probe_post(void *data,
524 struct task_struct *prev, struct task_struct *next)
526 struct trace_array *tr = data;
527 struct trace_pid_list *pid_list;
529 pid_list = rcu_dereference_sched(tr->filtered_pids);
531 this_cpu_write(tr->trace_buffer.data->ignore_pid,
532 check_ignore_pid(pid_list, next));
536 event_filter_pid_sched_wakeup_probe_pre(void *data, struct task_struct *task)
538 struct trace_array *tr = data;
539 struct trace_pid_list *pid_list;
541 /* Nothing to do if we are already tracing */
542 if (!this_cpu_read(tr->trace_buffer.data->ignore_pid))
545 pid_list = rcu_dereference_sched(tr->filtered_pids);
547 this_cpu_write(tr->trace_buffer.data->ignore_pid,
548 check_ignore_pid(pid_list, task));
552 event_filter_pid_sched_wakeup_probe_post(void *data, struct task_struct *task)
554 struct trace_array *tr = data;
555 struct trace_pid_list *pid_list;
557 /* Nothing to do if we are not tracing */
558 if (this_cpu_read(tr->trace_buffer.data->ignore_pid))
561 pid_list = rcu_dereference_sched(tr->filtered_pids);
563 /* Set tracing if current is enabled */
564 this_cpu_write(tr->trace_buffer.data->ignore_pid,
565 check_ignore_pid(pid_list, current));
568 static void __ftrace_clear_event_pids(struct trace_array *tr)
570 struct trace_pid_list *pid_list;
571 struct trace_event_file *file;
574 pid_list = rcu_dereference_protected(tr->filtered_pids,
575 lockdep_is_held(&event_mutex));
579 unregister_trace_sched_switch(event_filter_pid_sched_switch_probe_pre, tr);
580 unregister_trace_sched_switch(event_filter_pid_sched_switch_probe_post, tr);
582 unregister_trace_sched_wakeup(event_filter_pid_sched_wakeup_probe_pre, tr);
583 unregister_trace_sched_wakeup(event_filter_pid_sched_wakeup_probe_post, tr);
585 list_for_each_entry(file, &tr->events, list) {
586 clear_bit(EVENT_FILE_FL_PID_FILTER_BIT, &file->flags);
589 for_each_possible_cpu(cpu)
590 per_cpu_ptr(tr->trace_buffer.data, cpu)->ignore_pid = false;
592 rcu_assign_pointer(tr->filtered_pids, NULL);
594 /* Wait till all users are no longer using pid filtering */
597 free_pages((unsigned long)pid_list->pids, pid_list->order);
601 static void ftrace_clear_event_pids(struct trace_array *tr)
603 mutex_lock(&event_mutex);
604 __ftrace_clear_event_pids(tr);
605 mutex_unlock(&event_mutex);
608 static void __put_system(struct event_subsystem *system)
610 struct event_filter *filter = system->filter;
612 WARN_ON_ONCE(system_refcount(system) == 0);
613 if (system_refcount_dec(system))
616 list_del(&system->list);
619 kfree(filter->filter_string);
622 kfree_const(system->name);
626 static void __get_system(struct event_subsystem *system)
628 WARN_ON_ONCE(system_refcount(system) == 0);
629 system_refcount_inc(system);
632 static void __get_system_dir(struct trace_subsystem_dir *dir)
634 WARN_ON_ONCE(dir->ref_count == 0);
636 __get_system(dir->subsystem);
639 static void __put_system_dir(struct trace_subsystem_dir *dir)
641 WARN_ON_ONCE(dir->ref_count == 0);
642 /* If the subsystem is about to be freed, the dir must be too */
643 WARN_ON_ONCE(system_refcount(dir->subsystem) == 1 && dir->ref_count != 1);
645 __put_system(dir->subsystem);
646 if (!--dir->ref_count)
650 static void put_system(struct trace_subsystem_dir *dir)
652 mutex_lock(&event_mutex);
653 __put_system_dir(dir);
654 mutex_unlock(&event_mutex);
657 static void remove_subsystem(struct trace_subsystem_dir *dir)
662 if (!--dir->nr_events) {
663 tracefs_remove_recursive(dir->entry);
664 list_del(&dir->list);
665 __put_system_dir(dir);
669 static void remove_event_file_dir(struct trace_event_file *file)
671 struct dentry *dir = file->dir;
672 struct dentry *child;
675 spin_lock(&dir->d_lock); /* probably unneeded */
676 list_for_each_entry(child, &dir->d_subdirs, d_child) {
677 if (d_really_is_positive(child)) /* probably unneeded */
678 d_inode(child)->i_private = NULL;
680 spin_unlock(&dir->d_lock);
682 tracefs_remove_recursive(dir);
685 list_del(&file->list);
686 remove_subsystem(file->system);
687 free_event_filter(file->filter);
688 kmem_cache_free(file_cachep, file);
692 * __ftrace_set_clr_event(NULL, NULL, NULL, set) will set/unset all events.
695 __ftrace_set_clr_event_nolock(struct trace_array *tr, const char *match,
696 const char *sub, const char *event, int set)
698 struct trace_event_file *file;
699 struct trace_event_call *call;
703 list_for_each_entry(file, &tr->events, list) {
705 call = file->event_call;
706 name = trace_event_name(call);
708 if (!name || !call->class || !call->class->reg)
711 if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
715 strcmp(match, name) != 0 &&
716 strcmp(match, call->class->system) != 0)
719 if (sub && strcmp(sub, call->class->system) != 0)
722 if (event && strcmp(event, name) != 0)
725 ftrace_event_enable_disable(file, set);
733 static int __ftrace_set_clr_event(struct trace_array *tr, const char *match,
734 const char *sub, const char *event, int set)
738 mutex_lock(&event_mutex);
739 ret = __ftrace_set_clr_event_nolock(tr, match, sub, event, set);
740 mutex_unlock(&event_mutex);
745 static int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set)
747 char *event = NULL, *sub = NULL, *match;
751 * The buf format can be <subsystem>:<event-name>
752 * *:<event-name> means any event by that name.
753 * :<event-name> is the same.
755 * <subsystem>:* means all events in that subsystem
756 * <subsystem>: means the same.
758 * <name> (no ':') means all events in a subsystem with
759 * the name <name> or any event that matches <name>
762 match = strsep(&buf, ":");
768 if (!strlen(sub) || strcmp(sub, "*") == 0)
770 if (!strlen(event) || strcmp(event, "*") == 0)
774 ret = __ftrace_set_clr_event(tr, match, sub, event, set);
776 /* Put back the colon to allow this to be called again */
784 * trace_set_clr_event - enable or disable an event
785 * @system: system name to match (NULL for any system)
786 * @event: event name to match (NULL for all events, within system)
787 * @set: 1 to enable, 0 to disable
789 * This is a way for other parts of the kernel to enable or disable
792 * Returns 0 on success, -EINVAL if the parameters do not match any
795 int trace_set_clr_event(const char *system, const char *event, int set)
797 struct trace_array *tr = top_trace_array();
802 return __ftrace_set_clr_event(tr, NULL, system, event, set);
804 EXPORT_SYMBOL_GPL(trace_set_clr_event);
806 /* 128 should be much more than enough */
807 #define EVENT_BUF_SIZE 127
810 ftrace_event_write(struct file *file, const char __user *ubuf,
811 size_t cnt, loff_t *ppos)
813 struct trace_parser parser;
814 struct seq_file *m = file->private_data;
815 struct trace_array *tr = m->private;
821 ret = tracing_update_buffers();
825 if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1))
828 read = trace_get_user(&parser, ubuf, cnt, ppos);
830 if (read >= 0 && trace_parser_loaded((&parser))) {
833 if (*parser.buffer == '!')
836 parser.buffer[parser.idx] = 0;
838 ret = ftrace_set_clr_event(tr, parser.buffer + !set, set);
846 trace_parser_put(&parser);
852 t_next(struct seq_file *m, void *v, loff_t *pos)
854 struct trace_event_file *file = v;
855 struct trace_event_call *call;
856 struct trace_array *tr = m->private;
860 list_for_each_entry_continue(file, &tr->events, list) {
861 call = file->event_call;
863 * The ftrace subsystem is for showing formats only.
864 * They can not be enabled or disabled via the event files.
866 if (call->class && call->class->reg)
873 static void *t_start(struct seq_file *m, loff_t *pos)
875 struct trace_event_file *file;
876 struct trace_array *tr = m->private;
879 mutex_lock(&event_mutex);
881 file = list_entry(&tr->events, struct trace_event_file, list);
882 for (l = 0; l <= *pos; ) {
883 file = t_next(m, file, &l);
891 s_next(struct seq_file *m, void *v, loff_t *pos)
893 struct trace_event_file *file = v;
894 struct trace_array *tr = m->private;
898 list_for_each_entry_continue(file, &tr->events, list) {
899 if (file->flags & EVENT_FILE_FL_ENABLED)
906 static void *s_start(struct seq_file *m, loff_t *pos)
908 struct trace_event_file *file;
909 struct trace_array *tr = m->private;
912 mutex_lock(&event_mutex);
914 file = list_entry(&tr->events, struct trace_event_file, list);
915 for (l = 0; l <= *pos; ) {
916 file = s_next(m, file, &l);
923 static int t_show(struct seq_file *m, void *v)
925 struct trace_event_file *file = v;
926 struct trace_event_call *call = file->event_call;
928 if (strcmp(call->class->system, TRACE_SYSTEM) != 0)
929 seq_printf(m, "%s:", call->class->system);
930 seq_printf(m, "%s\n", trace_event_name(call));
935 static void t_stop(struct seq_file *m, void *p)
937 mutex_unlock(&event_mutex);
940 static void *p_start(struct seq_file *m, loff_t *pos)
942 struct trace_pid_list *pid_list;
943 struct trace_array *tr = m->private;
946 * Grab the mutex, to keep calls to p_next() having the same
947 * tr->filtered_pids as p_start() has.
948 * If we just passed the tr->filtered_pids around, then RCU would
949 * have been enough, but doing that makes things more complex.
951 mutex_lock(&event_mutex);
952 rcu_read_lock_sched();
954 pid_list = rcu_dereference_sched(tr->filtered_pids);
956 if (!pid_list || *pos >= pid_list->nr_pids)
959 return (void *)&pid_list->pids[*pos];
962 static void p_stop(struct seq_file *m, void *p)
964 rcu_read_unlock_sched();
965 mutex_unlock(&event_mutex);
969 p_next(struct seq_file *m, void *v, loff_t *pos)
971 struct trace_array *tr = m->private;
972 struct trace_pid_list *pid_list = rcu_dereference_sched(tr->filtered_pids);
976 if (*pos >= pid_list->nr_pids)
979 return (void *)&pid_list->pids[*pos];
982 static int p_show(struct seq_file *m, void *v)
986 seq_printf(m, "%d\n", *pid);
991 event_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
994 struct trace_event_file *file;
998 mutex_lock(&event_mutex);
999 file = event_file_data(filp);
1001 flags = file->flags;
1002 mutex_unlock(&event_mutex);
1007 if (flags & EVENT_FILE_FL_ENABLED &&
1008 !(flags & EVENT_FILE_FL_SOFT_DISABLED))
1011 if (flags & EVENT_FILE_FL_SOFT_DISABLED ||
1012 flags & EVENT_FILE_FL_SOFT_MODE)
1017 return simple_read_from_buffer(ubuf, cnt, ppos, buf, strlen(buf));
1021 event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
1024 struct trace_event_file *file;
1028 ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
1032 ret = tracing_update_buffers();
1040 mutex_lock(&event_mutex);
1041 file = event_file_data(filp);
1043 ret = ftrace_event_enable_disable(file, val);
1044 mutex_unlock(&event_mutex);
1053 return ret ? ret : cnt;
1057 system_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
1060 const char set_to_char[4] = { '?', '0', '1', 'X' };
1061 struct trace_subsystem_dir *dir = filp->private_data;
1062 struct event_subsystem *system = dir->subsystem;
1063 struct trace_event_call *call;
1064 struct trace_event_file *file;
1065 struct trace_array *tr = dir->tr;
1070 mutex_lock(&event_mutex);
1071 list_for_each_entry(file, &tr->events, list) {
1072 call = file->event_call;
1073 if (!trace_event_name(call) || !call->class || !call->class->reg)
1076 if (system && strcmp(call->class->system, system->name) != 0)
1080 * We need to find out if all the events are set
1081 * or if all events or cleared, or if we have
1084 set |= (1 << !!(file->flags & EVENT_FILE_FL_ENABLED));
1087 * If we have a mixture, no need to look further.
1092 mutex_unlock(&event_mutex);
1094 buf[0] = set_to_char[set];
1097 ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, 2);
1103 system_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
1106 struct trace_subsystem_dir *dir = filp->private_data;
1107 struct event_subsystem *system = dir->subsystem;
1108 const char *name = NULL;
1112 ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
1116 ret = tracing_update_buffers();
1120 if (val != 0 && val != 1)
1124 * Opening of "enable" adds a ref count to system,
1125 * so the name is safe to use.
1128 name = system->name;
1130 ret = __ftrace_set_clr_event(dir->tr, NULL, name, NULL, val);
1144 FORMAT_FIELD_SEPERATOR = 2,
1145 FORMAT_PRINTFMT = 3,
1148 static void *f_next(struct seq_file *m, void *v, loff_t *pos)
1150 struct trace_event_call *call = event_file_data(m->private);
1151 struct list_head *common_head = &ftrace_common_fields;
1152 struct list_head *head = trace_get_fields(call);
1153 struct list_head *node = v;
1157 switch ((unsigned long)v) {
1162 case FORMAT_FIELD_SEPERATOR:
1166 case FORMAT_PRINTFMT:
1172 if (node == common_head)
1173 return (void *)FORMAT_FIELD_SEPERATOR;
1174 else if (node == head)
1175 return (void *)FORMAT_PRINTFMT;
1180 static int f_show(struct seq_file *m, void *v)
1182 struct trace_event_call *call = event_file_data(m->private);
1183 struct ftrace_event_field *field;
1184 const char *array_descriptor;
1186 switch ((unsigned long)v) {
1188 seq_printf(m, "name: %s\n", trace_event_name(call));
1189 seq_printf(m, "ID: %d\n", call->event.type);
1190 seq_puts(m, "format:\n");
1193 case FORMAT_FIELD_SEPERATOR:
1197 case FORMAT_PRINTFMT:
1198 seq_printf(m, "\nprint fmt: %s\n",
1203 field = list_entry(v, struct ftrace_event_field, link);
1205 * Smartly shows the array type(except dynamic array).
1208 * If TYPE := TYPE[LEN], it is shown:
1209 * field:TYPE VAR[LEN]
1211 array_descriptor = strchr(field->type, '[');
1213 if (!strncmp(field->type, "__data_loc", 10))
1214 array_descriptor = NULL;
1216 if (!array_descriptor)
1217 seq_printf(m, "\tfield:%s %s;\toffset:%u;\tsize:%u;\tsigned:%d;\n",
1218 field->type, field->name, field->offset,
1219 field->size, !!field->is_signed);
1221 seq_printf(m, "\tfield:%.*s %s%s;\toffset:%u;\tsize:%u;\tsigned:%d;\n",
1222 (int)(array_descriptor - field->type),
1223 field->type, field->name,
1224 array_descriptor, field->offset,
1225 field->size, !!field->is_signed);
1230 static void *f_start(struct seq_file *m, loff_t *pos)
1232 void *p = (void *)FORMAT_HEADER;
1235 /* ->stop() is called even if ->start() fails */
1236 mutex_lock(&event_mutex);
1237 if (!event_file_data(m->private))
1238 return ERR_PTR(-ENODEV);
1240 while (l < *pos && p)
1241 p = f_next(m, p, &l);
1246 static void f_stop(struct seq_file *m, void *p)
1248 mutex_unlock(&event_mutex);
1251 static const struct seq_operations trace_format_seq_ops = {
1258 static int trace_format_open(struct inode *inode, struct file *file)
1263 ret = seq_open(file, &trace_format_seq_ops);
1267 m = file->private_data;
1274 event_id_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
1276 int id = (long)event_file_data(filp);
1286 len = sprintf(buf, "%d\n", id);
1288 return simple_read_from_buffer(ubuf, cnt, ppos, buf, len);
1292 event_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
1295 struct trace_event_file *file;
1296 struct trace_seq *s;
1302 s = kmalloc(sizeof(*s), GFP_KERNEL);
1309 mutex_lock(&event_mutex);
1310 file = event_file_data(filp);
1312 print_event_filter(file, s);
1313 mutex_unlock(&event_mutex);
1316 r = simple_read_from_buffer(ubuf, cnt, ppos,
1317 s->buffer, trace_seq_used(s));
1325 event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
1328 struct trace_event_file *file;
1332 if (cnt >= PAGE_SIZE)
1335 buf = (char *)__get_free_page(GFP_TEMPORARY);
1339 if (copy_from_user(buf, ubuf, cnt)) {
1340 free_page((unsigned long) buf);
1345 mutex_lock(&event_mutex);
1346 file = event_file_data(filp);
1348 err = apply_event_filter(file, buf);
1349 mutex_unlock(&event_mutex);
1351 free_page((unsigned long) buf);
1360 static LIST_HEAD(event_subsystems);
1362 static int subsystem_open(struct inode *inode, struct file *filp)
1364 struct event_subsystem *system = NULL;
1365 struct trace_subsystem_dir *dir = NULL; /* Initialize for gcc */
1366 struct trace_array *tr;
1369 if (tracing_is_disabled())
1372 /* Make sure the system still exists */
1373 mutex_lock(&trace_types_lock);
1374 mutex_lock(&event_mutex);
1375 list_for_each_entry(tr, &ftrace_trace_arrays, list) {
1376 list_for_each_entry(dir, &tr->systems, list) {
1377 if (dir == inode->i_private) {
1378 /* Don't open systems with no events */
1379 if (dir->nr_events) {
1380 __get_system_dir(dir);
1381 system = dir->subsystem;
1388 mutex_unlock(&event_mutex);
1389 mutex_unlock(&trace_types_lock);
1394 /* Some versions of gcc think dir can be uninitialized here */
1397 /* Still need to increment the ref count of the system */
1398 if (trace_array_get(tr) < 0) {
1403 ret = tracing_open_generic(inode, filp);
1405 trace_array_put(tr);
1412 static int system_tr_open(struct inode *inode, struct file *filp)
1414 struct trace_subsystem_dir *dir;
1415 struct trace_array *tr = inode->i_private;
1418 if (tracing_is_disabled())
1421 if (trace_array_get(tr) < 0)
1424 /* Make a temporary dir that has no system but points to tr */
1425 dir = kzalloc(sizeof(*dir), GFP_KERNEL);
1427 trace_array_put(tr);
1433 ret = tracing_open_generic(inode, filp);
1435 trace_array_put(tr);
1440 filp->private_data = dir;
1445 static int subsystem_release(struct inode *inode, struct file *file)
1447 struct trace_subsystem_dir *dir = file->private_data;
1449 trace_array_put(dir->tr);
1452 * If dir->subsystem is NULL, then this is a temporary
1453 * descriptor that was made for a trace_array to enable
1465 subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
1468 struct trace_subsystem_dir *dir = filp->private_data;
1469 struct event_subsystem *system = dir->subsystem;
1470 struct trace_seq *s;
1476 s = kmalloc(sizeof(*s), GFP_KERNEL);
1482 print_subsystem_event_filter(system, s);
1483 r = simple_read_from_buffer(ubuf, cnt, ppos,
1484 s->buffer, trace_seq_used(s));
1492 subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
1495 struct trace_subsystem_dir *dir = filp->private_data;
1499 if (cnt >= PAGE_SIZE)
1502 buf = (char *)__get_free_page(GFP_TEMPORARY);
1506 if (copy_from_user(buf, ubuf, cnt)) {
1507 free_page((unsigned long) buf);
1512 err = apply_subsystem_event_filter(dir, buf);
1513 free_page((unsigned long) buf);
1523 show_header(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
1525 int (*func)(struct trace_seq *s) = filp->private_data;
1526 struct trace_seq *s;
1532 s = kmalloc(sizeof(*s), GFP_KERNEL);
1539 r = simple_read_from_buffer(ubuf, cnt, ppos,
1540 s->buffer, trace_seq_used(s));
1547 static int max_pids(struct trace_pid_list *pid_list)
1549 return (PAGE_SIZE << pid_list->order) / sizeof(pid_t);
1552 static void ignore_task_cpu(void *data)
1554 struct trace_array *tr = data;
1555 struct trace_pid_list *pid_list;
1558 * This function is called by on_each_cpu() while the
1559 * event_mutex is held.
1561 pid_list = rcu_dereference_protected(tr->filtered_pids,
1562 mutex_is_locked(&event_mutex));
1564 this_cpu_write(tr->trace_buffer.data->ignore_pid,
1565 check_ignore_pid(pid_list, current));
1569 ftrace_event_pid_write(struct file *filp, const char __user *ubuf,
1570 size_t cnt, loff_t *ppos)
1572 struct seq_file *m = filp->private_data;
1573 struct trace_array *tr = m->private;
1574 struct trace_pid_list *filtered_pids = NULL;
1575 struct trace_pid_list *pid_list = NULL;
1576 struct trace_event_file *file;
1577 struct trace_parser parser;
1588 ret = tracing_update_buffers();
1592 if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1))
1595 mutex_lock(&event_mutex);
1597 * Load as many pids into the array before doing a
1598 * swap from the tr->filtered_pids to the new list.
1604 ret = trace_get_user(&parser, ubuf, cnt, &this_pos);
1605 if (ret < 0 || !trace_parser_loaded(&parser))
1612 parser.buffer[parser.idx] = 0;
1615 if (kstrtoul(parser.buffer, 0, &val))
1624 pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL);
1628 filtered_pids = rcu_dereference_protected(tr->filtered_pids,
1629 lockdep_is_held(&event_mutex));
1631 pid_list->order = filtered_pids->order;
1633 pid_list->order = 0;
1635 pid_list->pids = (void *)__get_free_pages(GFP_KERNEL,
1637 if (!pid_list->pids)
1640 if (filtered_pids) {
1641 pid_list->nr_pids = filtered_pids->nr_pids;
1642 memcpy(pid_list->pids, filtered_pids->pids,
1643 pid_list->nr_pids * sizeof(pid_t));
1645 pid_list->nr_pids = 0;
1648 if (pid_list->nr_pids >= max_pids(pid_list)) {
1651 pid_page = (void *)__get_free_pages(GFP_KERNEL,
1652 pid_list->order + 1);
1655 memcpy(pid_page, pid_list->pids,
1656 pid_list->nr_pids * sizeof(pid_t));
1657 free_pages((unsigned long)pid_list->pids, pid_list->order);
1660 pid_list->pids = pid_page;
1663 pid_list->pids[pid_list->nr_pids++] = pid;
1664 trace_parser_clear(&parser);
1667 trace_parser_put(&parser);
1671 free_pages((unsigned long)pid_list->pids, pid_list->order);
1673 mutex_unlock(&event_mutex);
1678 mutex_unlock(&event_mutex);
1682 sort(pid_list->pids, pid_list->nr_pids, sizeof(pid_t), cmp_pid, NULL);
1684 /* Remove duplicates */
1685 for (i = 1; i < pid_list->nr_pids; i++) {
1688 while (i < pid_list->nr_pids &&
1689 pid_list->pids[i - 1] == pid_list->pids[i])
1693 if (i < pid_list->nr_pids) {
1694 memmove(&pid_list->pids[start], &pid_list->pids[i],
1695 (pid_list->nr_pids - i) * sizeof(pid_t));
1696 pid_list->nr_pids -= i - start;
1699 pid_list->nr_pids = start;
1703 rcu_assign_pointer(tr->filtered_pids, pid_list);
1705 list_for_each_entry(file, &tr->events, list) {
1706 set_bit(EVENT_FILE_FL_PID_FILTER_BIT, &file->flags);
1709 if (filtered_pids) {
1710 synchronize_sched();
1712 free_pages((unsigned long)filtered_pids->pids, filtered_pids->order);
1713 kfree(filtered_pids);
1716 * Register a probe that is called before all other probes
1717 * to set ignore_pid if next or prev do not match.
1718 * Register a probe this is called after all other probes
1719 * to only keep ignore_pid set if next pid matches.
1721 register_trace_prio_sched_switch(event_filter_pid_sched_switch_probe_pre,
1723 register_trace_prio_sched_switch(event_filter_pid_sched_switch_probe_post,
1726 register_trace_prio_sched_wakeup(event_filter_pid_sched_wakeup_probe_pre,
1728 register_trace_prio_sched_wakeup(event_filter_pid_sched_wakeup_probe_post,
1732 * Ignoring of pids is done at task switch. But we have to
1733 * check for those tasks that are currently running.
1735 on_each_cpu(ignore_task_cpu, tr, 1);
1738 mutex_unlock(&event_mutex);
1746 static int ftrace_event_avail_open(struct inode *inode, struct file *file);
1747 static int ftrace_event_set_open(struct inode *inode, struct file *file);
1748 static int ftrace_event_set_pid_open(struct inode *inode, struct file *file);
1749 static int ftrace_event_release(struct inode *inode, struct file *file);
1751 static const struct seq_operations show_event_seq_ops = {
1758 static const struct seq_operations show_set_event_seq_ops = {
1765 static const struct seq_operations show_set_pid_seq_ops = {
1772 static const struct file_operations ftrace_avail_fops = {
1773 .open = ftrace_event_avail_open,
1775 .llseek = seq_lseek,
1776 .release = seq_release,
1779 static const struct file_operations ftrace_set_event_fops = {
1780 .open = ftrace_event_set_open,
1782 .write = ftrace_event_write,
1783 .llseek = seq_lseek,
1784 .release = ftrace_event_release,
1787 static const struct file_operations ftrace_set_event_pid_fops = {
1788 .open = ftrace_event_set_pid_open,
1790 .write = ftrace_event_pid_write,
1791 .llseek = seq_lseek,
1792 .release = ftrace_event_release,
1795 static const struct file_operations ftrace_enable_fops = {
1796 .open = tracing_open_generic,
1797 .read = event_enable_read,
1798 .write = event_enable_write,
1799 .llseek = default_llseek,
1802 static const struct file_operations ftrace_event_format_fops = {
1803 .open = trace_format_open,
1805 .llseek = seq_lseek,
1806 .release = seq_release,
1809 static const struct file_operations ftrace_event_id_fops = {
1810 .read = event_id_read,
1811 .llseek = default_llseek,
1814 static const struct file_operations ftrace_event_filter_fops = {
1815 .open = tracing_open_generic,
1816 .read = event_filter_read,
1817 .write = event_filter_write,
1818 .llseek = default_llseek,
1821 static const struct file_operations ftrace_subsystem_filter_fops = {
1822 .open = subsystem_open,
1823 .read = subsystem_filter_read,
1824 .write = subsystem_filter_write,
1825 .llseek = default_llseek,
1826 .release = subsystem_release,
1829 static const struct file_operations ftrace_system_enable_fops = {
1830 .open = subsystem_open,
1831 .read = system_enable_read,
1832 .write = system_enable_write,
1833 .llseek = default_llseek,
1834 .release = subsystem_release,
1837 static const struct file_operations ftrace_tr_enable_fops = {
1838 .open = system_tr_open,
1839 .read = system_enable_read,
1840 .write = system_enable_write,
1841 .llseek = default_llseek,
1842 .release = subsystem_release,
1845 static const struct file_operations ftrace_show_header_fops = {
1846 .open = tracing_open_generic,
1847 .read = show_header,
1848 .llseek = default_llseek,
1852 ftrace_event_open(struct inode *inode, struct file *file,
1853 const struct seq_operations *seq_ops)
1858 ret = seq_open(file, seq_ops);
1861 m = file->private_data;
1862 /* copy tr over to seq ops */
1863 m->private = inode->i_private;
1868 static int ftrace_event_release(struct inode *inode, struct file *file)
1870 struct trace_array *tr = inode->i_private;
1872 trace_array_put(tr);
1874 return seq_release(inode, file);
1878 ftrace_event_avail_open(struct inode *inode, struct file *file)
1880 const struct seq_operations *seq_ops = &show_event_seq_ops;
1882 return ftrace_event_open(inode, file, seq_ops);
1886 ftrace_event_set_open(struct inode *inode, struct file *file)
1888 const struct seq_operations *seq_ops = &show_set_event_seq_ops;
1889 struct trace_array *tr = inode->i_private;
1892 if (trace_array_get(tr) < 0)
1895 if ((file->f_mode & FMODE_WRITE) &&
1896 (file->f_flags & O_TRUNC))
1897 ftrace_clear_events(tr);
1899 ret = ftrace_event_open(inode, file, seq_ops);
1901 trace_array_put(tr);
1906 ftrace_event_set_pid_open(struct inode *inode, struct file *file)
1908 const struct seq_operations *seq_ops = &show_set_pid_seq_ops;
1909 struct trace_array *tr = inode->i_private;
1912 if (trace_array_get(tr) < 0)
1915 if ((file->f_mode & FMODE_WRITE) &&
1916 (file->f_flags & O_TRUNC))
1917 ftrace_clear_event_pids(tr);
1919 ret = ftrace_event_open(inode, file, seq_ops);
1921 trace_array_put(tr);
1925 static struct event_subsystem *
1926 create_new_subsystem(const char *name)
1928 struct event_subsystem *system;
1930 /* need to create new entry */
1931 system = kmalloc(sizeof(*system), GFP_KERNEL);
1935 system->ref_count = 1;
1937 /* Only allocate if dynamic (kprobes and modules) */
1938 system->name = kstrdup_const(name, GFP_KERNEL);
1942 system->filter = NULL;
1944 system->filter = kzalloc(sizeof(struct event_filter), GFP_KERNEL);
1945 if (!system->filter)
1948 list_add(&system->list, &event_subsystems);
1953 kfree_const(system->name);
1958 static struct dentry *
1959 event_subsystem_dir(struct trace_array *tr, const char *name,
1960 struct trace_event_file *file, struct dentry *parent)
1962 struct trace_subsystem_dir *dir;
1963 struct event_subsystem *system;
1964 struct dentry *entry;
1966 /* First see if we did not already create this dir */
1967 list_for_each_entry(dir, &tr->systems, list) {
1968 system = dir->subsystem;
1969 if (strcmp(system->name, name) == 0) {
1976 /* Now see if the system itself exists. */
1977 list_for_each_entry(system, &event_subsystems, list) {
1978 if (strcmp(system->name, name) == 0)
1981 /* Reset system variable when not found */
1982 if (&system->list == &event_subsystems)
1985 dir = kmalloc(sizeof(*dir), GFP_KERNEL);
1990 system = create_new_subsystem(name);
1994 __get_system(system);
1996 dir->entry = tracefs_create_dir(name, parent);
1998 pr_warn("Failed to create system directory %s\n", name);
1999 __put_system(system);
2006 dir->subsystem = system;
2009 entry = tracefs_create_file("filter", 0644, dir->entry, dir,
2010 &ftrace_subsystem_filter_fops);
2012 kfree(system->filter);
2013 system->filter = NULL;
2014 pr_warn("Could not create tracefs '%s/filter' entry\n", name);
2017 trace_create_file("enable", 0644, dir->entry, dir,
2018 &ftrace_system_enable_fops);
2020 list_add(&dir->list, &tr->systems);
2027 /* Only print this message if failed on memory allocation */
2028 if (!dir || !system)
2029 pr_warn("No memory to create event subsystem %s\n", name);
2034 event_create_dir(struct dentry *parent, struct trace_event_file *file)
2036 struct trace_event_call *call = file->event_call;
2037 struct trace_array *tr = file->tr;
2038 struct list_head *head;
2039 struct dentry *d_events;
2044 * If the trace point header did not define TRACE_SYSTEM
2045 * then the system would be called "TRACE_SYSTEM".
2047 if (strcmp(call->class->system, TRACE_SYSTEM) != 0) {
2048 d_events = event_subsystem_dir(tr, call->class->system, file, parent);
2054 name = trace_event_name(call);
2055 file->dir = tracefs_create_dir(name, d_events);
2057 pr_warn("Could not create tracefs '%s' directory\n", name);
2061 if (call->class->reg && !(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE))
2062 trace_create_file("enable", 0644, file->dir, file,
2063 &ftrace_enable_fops);
2065 #ifdef CONFIG_PERF_EVENTS
2066 if (call->event.type && call->class->reg)
2067 trace_create_file("id", 0444, file->dir,
2068 (void *)(long)call->event.type,
2069 &ftrace_event_id_fops);
2073 * Other events may have the same class. Only update
2074 * the fields if they are not already defined.
2076 head = trace_get_fields(call);
2077 if (list_empty(head)) {
2078 ret = call->class->define_fields(call);
2080 pr_warn("Could not initialize trace point events/%s\n",
2085 trace_create_file("filter", 0644, file->dir, file,
2086 &ftrace_event_filter_fops);
2088 trace_create_file("trigger", 0644, file->dir, file,
2089 &event_trigger_fops);
2091 trace_create_file("format", 0444, file->dir, call,
2092 &ftrace_event_format_fops);
2097 static void remove_event_from_tracers(struct trace_event_call *call)
2099 struct trace_event_file *file;
2100 struct trace_array *tr;
2102 do_for_each_event_file_safe(tr, file) {
2103 if (file->event_call != call)
2106 remove_event_file_dir(file);
2108 * The do_for_each_event_file_safe() is
2109 * a double loop. After finding the call for this
2110 * trace_array, we use break to jump to the next
2114 } while_for_each_event_file();
2117 static void event_remove(struct trace_event_call *call)
2119 struct trace_array *tr;
2120 struct trace_event_file *file;
2122 do_for_each_event_file(tr, file) {
2123 if (file->event_call != call)
2125 ftrace_event_enable_disable(file, 0);
2127 * The do_for_each_event_file() is
2128 * a double loop. After finding the call for this
2129 * trace_array, we use break to jump to the next
2133 } while_for_each_event_file();
2135 if (call->event.funcs)
2136 __unregister_trace_event(&call->event);
2137 remove_event_from_tracers(call);
2138 list_del(&call->list);
2141 static int event_init(struct trace_event_call *call)
2146 name = trace_event_name(call);
2150 if (call->class->raw_init) {
2151 ret = call->class->raw_init(call);
2152 if (ret < 0 && ret != -ENOSYS)
2153 pr_warn("Could not initialize trace events/%s\n", name);
2160 __register_event(struct trace_event_call *call, struct module *mod)
2164 ret = event_init(call);
2168 list_add(&call->list, &ftrace_events);
2174 static char *enum_replace(char *ptr, struct trace_enum_map *map, int len)
2179 /* Find the length of the enum value as a string */
2180 elen = snprintf(ptr, 0, "%ld", map->enum_value);
2181 /* Make sure there's enough room to replace the string with the value */
2185 snprintf(ptr, elen + 1, "%ld", map->enum_value);
2187 /* Get the rest of the string of ptr */
2188 rlen = strlen(ptr + len);
2189 memmove(ptr + elen, ptr + len, rlen);
2190 /* Make sure we end the new string */
2191 ptr[elen + rlen] = 0;
2196 static void update_event_printk(struct trace_event_call *call,
2197 struct trace_enum_map *map)
2201 int len = strlen(map->enum_string);
2203 for (ptr = call->print_fmt; *ptr; ptr++) {
2217 if (isdigit(*ptr)) {
2221 /* Check for alpha chars like ULL */
2222 } while (isalnum(*ptr));
2226 * A number must have some kind of delimiter after
2227 * it, and we can ignore that too.
2231 if (isalpha(*ptr) || *ptr == '_') {
2232 if (strncmp(map->enum_string, ptr, len) == 0 &&
2233 !isalnum(ptr[len]) && ptr[len] != '_') {
2234 ptr = enum_replace(ptr, map, len);
2235 /* Hmm, enum string smaller than value */
2236 if (WARN_ON_ONCE(!ptr))
2239 * No need to decrement here, as enum_replace()
2240 * returns the pointer to the character passed
2241 * the enum, and two enums can not be placed
2242 * back to back without something in between.
2243 * We can skip that something in between.
2250 } while (isalnum(*ptr) || *ptr == '_');
2254 * If what comes after this variable is a '.' or
2255 * '->' then we can continue to ignore that string.
2257 if (*ptr == '.' || (ptr[0] == '-' && ptr[1] == '>')) {
2258 ptr += *ptr == '.' ? 1 : 2;
2264 * Once again, we can skip the delimiter that came
2272 void trace_event_enum_update(struct trace_enum_map **map, int len)
2274 struct trace_event_call *call, *p;
2275 const char *last_system = NULL;
2279 down_write(&trace_event_sem);
2280 list_for_each_entry_safe(call, p, &ftrace_events, list) {
2281 /* events are usually grouped together with systems */
2282 if (!last_system || call->class->system != last_system) {
2284 last_system = call->class->system;
2287 for (i = last_i; i < len; i++) {
2288 if (call->class->system == map[i]->system) {
2289 /* Save the first system if need be */
2292 update_event_printk(call, map[i]);
2296 up_write(&trace_event_sem);
2299 static struct trace_event_file *
2300 trace_create_new_event(struct trace_event_call *call,
2301 struct trace_array *tr)
2303 struct trace_event_file *file;
2305 file = kmem_cache_alloc(file_cachep, GFP_TRACE);
2309 file->event_call = call;
2311 atomic_set(&file->sm_ref, 0);
2312 atomic_set(&file->tm_ref, 0);
2313 INIT_LIST_HEAD(&file->triggers);
2314 list_add(&file->list, &tr->events);
2319 /* Add an event to a trace directory */
2321 __trace_add_new_event(struct trace_event_call *call, struct trace_array *tr)
2323 struct trace_event_file *file;
2325 file = trace_create_new_event(call, tr);
2329 return event_create_dir(tr->event_dir, file);
2333 * Just create a decriptor for early init. A descriptor is required
2334 * for enabling events at boot. We want to enable events before
2335 * the filesystem is initialized.
2338 __trace_early_add_new_event(struct trace_event_call *call,
2339 struct trace_array *tr)
2341 struct trace_event_file *file;
2343 file = trace_create_new_event(call, tr);
2350 struct ftrace_module_file_ops;
2351 static void __add_event_to_tracers(struct trace_event_call *call);
2353 /* Add an additional event_call dynamically */
2354 int trace_add_event_call(struct trace_event_call *call)
2357 mutex_lock(&trace_types_lock);
2358 mutex_lock(&event_mutex);
2360 ret = __register_event(call, NULL);
2362 __add_event_to_tracers(call);
2364 mutex_unlock(&event_mutex);
2365 mutex_unlock(&trace_types_lock);
2370 * Must be called under locking of trace_types_lock, event_mutex and
2373 static void __trace_remove_event_call(struct trace_event_call *call)
2376 trace_destroy_fields(call);
2377 free_event_filter(call->filter);
2378 call->filter = NULL;
2381 static int probe_remove_event_call(struct trace_event_call *call)
2383 struct trace_array *tr;
2384 struct trace_event_file *file;
2386 #ifdef CONFIG_PERF_EVENTS
2387 if (call->perf_refcount)
2390 do_for_each_event_file(tr, file) {
2391 if (file->event_call != call)
2394 * We can't rely on ftrace_event_enable_disable(enable => 0)
2395 * we are going to do, EVENT_FILE_FL_SOFT_MODE can suppress
2396 * TRACE_REG_UNREGISTER.
2398 if (file->flags & EVENT_FILE_FL_ENABLED)
2401 * The do_for_each_event_file_safe() is
2402 * a double loop. After finding the call for this
2403 * trace_array, we use break to jump to the next
2407 } while_for_each_event_file();
2409 __trace_remove_event_call(call);
2414 /* Remove an event_call */
2415 int trace_remove_event_call(struct trace_event_call *call)
2419 mutex_lock(&trace_types_lock);
2420 mutex_lock(&event_mutex);
2421 down_write(&trace_event_sem);
2422 ret = probe_remove_event_call(call);
2423 up_write(&trace_event_sem);
2424 mutex_unlock(&event_mutex);
2425 mutex_unlock(&trace_types_lock);
2430 #define for_each_event(event, start, end) \
2431 for (event = start; \
2432 (unsigned long)event < (unsigned long)end; \
2435 #ifdef CONFIG_MODULES
2437 static void trace_module_add_events(struct module *mod)
2439 struct trace_event_call **call, **start, **end;
2441 if (!mod->num_trace_events)
2444 /* Don't add infrastructure for mods without tracepoints */
2445 if (trace_module_has_bad_taint(mod)) {
2446 pr_err("%s: module has bad taint, not creating trace events\n",
2451 start = mod->trace_events;
2452 end = mod->trace_events + mod->num_trace_events;
2454 for_each_event(call, start, end) {
2455 __register_event(*call, mod);
2456 __add_event_to_tracers(*call);
2460 static void trace_module_remove_events(struct module *mod)
2462 struct trace_event_call *call, *p;
2463 bool clear_trace = false;
2465 down_write(&trace_event_sem);
2466 list_for_each_entry_safe(call, p, &ftrace_events, list) {
2467 if (call->mod == mod) {
2468 if (call->flags & TRACE_EVENT_FL_WAS_ENABLED)
2470 __trace_remove_event_call(call);
2473 up_write(&trace_event_sem);
2476 * It is safest to reset the ring buffer if the module being unloaded
2477 * registered any events that were used. The only worry is if
2478 * a new module gets loaded, and takes on the same id as the events
2479 * of this module. When printing out the buffer, traced events left
2480 * over from this module may be passed to the new module events and
2481 * unexpected results may occur.
2484 tracing_reset_all_online_cpus();
2487 static int trace_module_notify(struct notifier_block *self,
2488 unsigned long val, void *data)
2490 struct module *mod = data;
2492 mutex_lock(&trace_types_lock);
2493 mutex_lock(&event_mutex);
2495 case MODULE_STATE_COMING:
2496 trace_module_add_events(mod);
2498 case MODULE_STATE_GOING:
2499 trace_module_remove_events(mod);
2502 mutex_unlock(&event_mutex);
2503 mutex_unlock(&trace_types_lock);
2508 static struct notifier_block trace_module_nb = {
2509 .notifier_call = trace_module_notify,
2510 .priority = 1, /* higher than trace.c module notify */
2512 #endif /* CONFIG_MODULES */
2514 /* Create a new event directory structure for a trace directory. */
2516 __trace_add_event_dirs(struct trace_array *tr)
2518 struct trace_event_call *call;
2521 list_for_each_entry(call, &ftrace_events, list) {
2522 ret = __trace_add_new_event(call, tr);
2524 pr_warn("Could not create directory for event %s\n",
2525 trace_event_name(call));
2529 struct trace_event_file *
2530 find_event_file(struct trace_array *tr, const char *system, const char *event)
2532 struct trace_event_file *file;
2533 struct trace_event_call *call;
2536 list_for_each_entry(file, &tr->events, list) {
2538 call = file->event_call;
2539 name = trace_event_name(call);
2541 if (!name || !call->class || !call->class->reg)
2544 if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
2547 if (strcmp(event, name) == 0 &&
2548 strcmp(system, call->class->system) == 0)
2554 #ifdef CONFIG_DYNAMIC_FTRACE
2557 #define ENABLE_EVENT_STR "enable_event"
2558 #define DISABLE_EVENT_STR "disable_event"
2560 struct event_probe_data {
2561 struct trace_event_file *file;
2562 unsigned long count;
2568 event_enable_probe(unsigned long ip, unsigned long parent_ip, void **_data)
2570 struct event_probe_data **pdata = (struct event_probe_data **)_data;
2571 struct event_probe_data *data = *pdata;
2577 clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &data->file->flags);
2579 set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &data->file->flags);
2583 event_enable_count_probe(unsigned long ip, unsigned long parent_ip, void **_data)
2585 struct event_probe_data **pdata = (struct event_probe_data **)_data;
2586 struct event_probe_data *data = *pdata;
2594 /* Skip if the event is in a state we want to switch to */
2595 if (data->enable == !(data->file->flags & EVENT_FILE_FL_SOFT_DISABLED))
2598 if (data->count != -1)
2601 event_enable_probe(ip, parent_ip, _data);
2605 event_enable_print(struct seq_file *m, unsigned long ip,
2606 struct ftrace_probe_ops *ops, void *_data)
2608 struct event_probe_data *data = _data;
2610 seq_printf(m, "%ps:", (void *)ip);
2612 seq_printf(m, "%s:%s:%s",
2613 data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR,
2614 data->file->event_call->class->system,
2615 trace_event_name(data->file->event_call));
2617 if (data->count == -1)
2618 seq_puts(m, ":unlimited\n");
2620 seq_printf(m, ":count=%ld\n", data->count);
2626 event_enable_init(struct ftrace_probe_ops *ops, unsigned long ip,
2629 struct event_probe_data **pdata = (struct event_probe_data **)_data;
2630 struct event_probe_data *data = *pdata;
2637 event_enable_free(struct ftrace_probe_ops *ops, unsigned long ip,
2640 struct event_probe_data **pdata = (struct event_probe_data **)_data;
2641 struct event_probe_data *data = *pdata;
2643 if (WARN_ON_ONCE(data->ref <= 0))
2648 /* Remove the SOFT_MODE flag */
2649 __ftrace_event_enable_disable(data->file, 0, 1);
2650 module_put(data->file->event_call->mod);
2656 static struct ftrace_probe_ops event_enable_probe_ops = {
2657 .func = event_enable_probe,
2658 .print = event_enable_print,
2659 .init = event_enable_init,
2660 .free = event_enable_free,
2663 static struct ftrace_probe_ops event_enable_count_probe_ops = {
2664 .func = event_enable_count_probe,
2665 .print = event_enable_print,
2666 .init = event_enable_init,
2667 .free = event_enable_free,
2670 static struct ftrace_probe_ops event_disable_probe_ops = {
2671 .func = event_enable_probe,
2672 .print = event_enable_print,
2673 .init = event_enable_init,
2674 .free = event_enable_free,
2677 static struct ftrace_probe_ops event_disable_count_probe_ops = {
2678 .func = event_enable_count_probe,
2679 .print = event_enable_print,
2680 .init = event_enable_init,
2681 .free = event_enable_free,
2685 event_enable_func(struct ftrace_hash *hash,
2686 char *glob, char *cmd, char *param, int enabled)
2688 struct trace_array *tr = top_trace_array();
2689 struct trace_event_file *file;
2690 struct ftrace_probe_ops *ops;
2691 struct event_probe_data *data;
2701 /* hash funcs only work with set_ftrace_filter */
2702 if (!enabled || !param)
2705 system = strsep(¶m, ":");
2709 event = strsep(¶m, ":");
2711 mutex_lock(&event_mutex);
2714 file = find_event_file(tr, system, event);
2718 enable = strcmp(cmd, ENABLE_EVENT_STR) == 0;
2721 ops = param ? &event_enable_count_probe_ops : &event_enable_probe_ops;
2723 ops = param ? &event_disable_count_probe_ops : &event_disable_probe_ops;
2725 if (glob[0] == '!') {
2726 unregister_ftrace_function_probe_func(glob+1, ops);
2732 data = kzalloc(sizeof(*data), GFP_KERNEL);
2736 data->enable = enable;
2743 number = strsep(¶m, ":");
2746 if (!strlen(number))
2750 * We use the callback data field (which is a pointer)
2753 ret = kstrtoul(number, 0, &data->count);
2758 /* Don't let event modules unload while probe registered */
2759 ret = try_module_get(file->event_call->mod);
2765 ret = __ftrace_event_enable_disable(file, 1, 1);
2768 ret = register_ftrace_function_probe(glob, ops, data);
2770 * The above returns on success the # of functions enabled,
2771 * but if it didn't find any functions it returns zero.
2772 * Consider no functions a failure too.
2779 /* Just return zero, not the number of enabled functions */
2782 mutex_unlock(&event_mutex);
2786 __ftrace_event_enable_disable(file, 0, 1);
2788 module_put(file->event_call->mod);
2794 static struct ftrace_func_command event_enable_cmd = {
2795 .name = ENABLE_EVENT_STR,
2796 .func = event_enable_func,
2799 static struct ftrace_func_command event_disable_cmd = {
2800 .name = DISABLE_EVENT_STR,
2801 .func = event_enable_func,
2804 static __init int register_event_cmds(void)
2808 ret = register_ftrace_command(&event_enable_cmd);
2809 if (WARN_ON(ret < 0))
2811 ret = register_ftrace_command(&event_disable_cmd);
2812 if (WARN_ON(ret < 0))
2813 unregister_ftrace_command(&event_enable_cmd);
2817 static inline int register_event_cmds(void) { return 0; }
2818 #endif /* CONFIG_DYNAMIC_FTRACE */
2821 * The top level array has already had its trace_event_file
2822 * descriptors created in order to allow for early events to
2823 * be recorded. This function is called after the tracefs has been
2824 * initialized, and we now have to create the files associated
2828 __trace_early_add_event_dirs(struct trace_array *tr)
2830 struct trace_event_file *file;
2834 list_for_each_entry(file, &tr->events, list) {
2835 ret = event_create_dir(tr->event_dir, file);
2837 pr_warn("Could not create directory for event %s\n",
2838 trace_event_name(file->event_call));
2843 * For early boot up, the top trace array requires to have
2844 * a list of events that can be enabled. This must be done before
2845 * the filesystem is set up in order to allow events to be traced
2849 __trace_early_add_events(struct trace_array *tr)
2851 struct trace_event_call *call;
2854 list_for_each_entry(call, &ftrace_events, list) {
2855 /* Early boot up should not have any modules loaded */
2856 if (WARN_ON_ONCE(call->mod))
2859 ret = __trace_early_add_new_event(call, tr);
2861 pr_warn("Could not create early event %s\n",
2862 trace_event_name(call));
2866 /* Remove the event directory structure for a trace directory. */
2868 __trace_remove_event_dirs(struct trace_array *tr)
2870 struct trace_event_file *file, *next;
2872 list_for_each_entry_safe(file, next, &tr->events, list)
2873 remove_event_file_dir(file);
2876 static void __add_event_to_tracers(struct trace_event_call *call)
2878 struct trace_array *tr;
2880 list_for_each_entry(tr, &ftrace_trace_arrays, list)
2881 __trace_add_new_event(call, tr);
2884 extern struct trace_event_call *__start_ftrace_events[];
2885 extern struct trace_event_call *__stop_ftrace_events[];
2887 static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata;
2889 static __init int setup_trace_event(char *str)
2891 strlcpy(bootup_event_buf, str, COMMAND_LINE_SIZE);
2892 ring_buffer_expanded = true;
2893 tracing_selftest_disabled = true;
2897 __setup("trace_event=", setup_trace_event);
2899 /* Expects to have event_mutex held when called */
2901 create_event_toplevel_files(struct dentry *parent, struct trace_array *tr)
2903 struct dentry *d_events;
2904 struct dentry *entry;
2906 entry = tracefs_create_file("set_event", 0644, parent,
2907 tr, &ftrace_set_event_fops);
2909 pr_warn("Could not create tracefs 'set_event' entry\n");
2913 d_events = tracefs_create_dir("events", parent);
2915 pr_warn("Could not create tracefs 'events' directory\n");
2919 entry = tracefs_create_file("set_event_pid", 0644, parent,
2920 tr, &ftrace_set_event_pid_fops);
2922 /* ring buffer internal formats */
2923 trace_create_file("header_page", 0444, d_events,
2924 ring_buffer_print_page_header,
2925 &ftrace_show_header_fops);
2927 trace_create_file("header_event", 0444, d_events,
2928 ring_buffer_print_entry_header,
2929 &ftrace_show_header_fops);
2931 trace_create_file("enable", 0644, d_events,
2932 tr, &ftrace_tr_enable_fops);
2934 tr->event_dir = d_events;
2940 * event_trace_add_tracer - add a instance of a trace_array to events
2941 * @parent: The parent dentry to place the files/directories for events in
2942 * @tr: The trace array associated with these events
2944 * When a new instance is created, it needs to set up its events
2945 * directory, as well as other files associated with events. It also
2946 * creates the event hierachry in the @parent/events directory.
2948 * Returns 0 on success.
2950 int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr)
2954 mutex_lock(&event_mutex);
2956 ret = create_event_toplevel_files(parent, tr);
2960 down_write(&trace_event_sem);
2961 __trace_add_event_dirs(tr);
2962 up_write(&trace_event_sem);
2965 mutex_unlock(&event_mutex);
2971 * The top trace array already had its file descriptors created.
2972 * Now the files themselves need to be created.
2975 early_event_add_tracer(struct dentry *parent, struct trace_array *tr)
2979 mutex_lock(&event_mutex);
2981 ret = create_event_toplevel_files(parent, tr);
2985 down_write(&trace_event_sem);
2986 __trace_early_add_event_dirs(tr);
2987 up_write(&trace_event_sem);
2990 mutex_unlock(&event_mutex);
2995 int event_trace_del_tracer(struct trace_array *tr)
2997 mutex_lock(&event_mutex);
2999 /* Disable any event triggers and associated soft-disabled events */
3000 clear_event_triggers(tr);
3002 /* Clear the pid list */
3003 __ftrace_clear_event_pids(tr);
3005 /* Disable any running events */
3006 __ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0);
3008 /* Access to events are within rcu_read_lock_sched() */
3009 synchronize_sched();
3011 down_write(&trace_event_sem);
3012 __trace_remove_event_dirs(tr);
3013 tracefs_remove_recursive(tr->event_dir);
3014 up_write(&trace_event_sem);
3016 tr->event_dir = NULL;
3018 mutex_unlock(&event_mutex);
3023 static __init int event_trace_memsetup(void)
3025 field_cachep = KMEM_CACHE(ftrace_event_field, SLAB_PANIC);
3026 file_cachep = KMEM_CACHE(trace_event_file, SLAB_PANIC);
3031 early_enable_events(struct trace_array *tr, bool disable_first)
3033 char *buf = bootup_event_buf;
3038 token = strsep(&buf, ",");
3045 /* Restarting syscalls requires that we stop them first */
3047 ftrace_set_clr_event(tr, token, 0);
3049 ret = ftrace_set_clr_event(tr, token, 1);
3051 pr_warn("Failed to enable trace event: %s\n", token);
3053 /* Put back the comma to allow this to be called again */
3059 static __init int event_trace_enable(void)
3061 struct trace_array *tr = top_trace_array();
3062 struct trace_event_call **iter, *call;
3068 for_each_event(iter, __start_ftrace_events, __stop_ftrace_events) {
3071 ret = event_init(call);
3073 list_add(&call->list, &ftrace_events);
3077 * We need the top trace array to have a working set of trace
3078 * points at early init, before the debug files and directories
3079 * are created. Create the file entries now, and attach them
3080 * to the actual file dentries later.
3082 __trace_early_add_events(tr);
3084 early_enable_events(tr, false);
3086 trace_printk_start_comm();
3088 register_event_cmds();
3090 register_trigger_cmds();
3096 * event_trace_enable() is called from trace_event_init() first to
3097 * initialize events and perhaps start any events that are on the
3098 * command line. Unfortunately, there are some events that will not
3099 * start this early, like the system call tracepoints that need
3100 * to set the TIF_SYSCALL_TRACEPOINT flag of pid 1. But event_trace_enable()
3101 * is called before pid 1 starts, and this flag is never set, making
3102 * the syscall tracepoint never get reached, but the event is enabled
3103 * regardless (and not doing anything).
3105 static __init int event_trace_enable_again(void)
3107 struct trace_array *tr;
3109 tr = top_trace_array();
3113 early_enable_events(tr, true);
3118 early_initcall(event_trace_enable_again);
3120 static __init int event_trace_init(void)
3122 struct trace_array *tr;
3123 struct dentry *d_tracer;
3124 struct dentry *entry;
3127 tr = top_trace_array();
3131 d_tracer = tracing_init_dentry();
3132 if (IS_ERR(d_tracer))
3135 entry = tracefs_create_file("available_events", 0444, d_tracer,
3136 tr, &ftrace_avail_fops);
3138 pr_warn("Could not create tracefs 'available_events' entry\n");
3140 if (trace_define_generic_fields())
3141 pr_warn("tracing: Failed to allocated generic fields");
3143 if (trace_define_common_fields())
3144 pr_warn("tracing: Failed to allocate common fields");
3146 ret = early_event_add_tracer(d_tracer, tr);
3150 #ifdef CONFIG_MODULES
3151 ret = register_module_notifier(&trace_module_nb);
3153 pr_warn("Failed to register trace events module notifier\n");
3158 void __init trace_event_init(void)
3160 event_trace_memsetup();
3161 init_ftrace_syscalls();
3162 event_trace_enable();
3165 fs_initcall(event_trace_init);
3167 #ifdef CONFIG_FTRACE_STARTUP_TEST
3169 static DEFINE_SPINLOCK(test_spinlock);
3170 static DEFINE_SPINLOCK(test_spinlock_irq);
3171 static DEFINE_MUTEX(test_mutex);
3173 static __init void test_work(struct work_struct *dummy)
3175 spin_lock(&test_spinlock);
3176 spin_lock_irq(&test_spinlock_irq);
3178 spin_unlock_irq(&test_spinlock_irq);
3179 spin_unlock(&test_spinlock);
3181 mutex_lock(&test_mutex);
3183 mutex_unlock(&test_mutex);
3186 static __init int event_test_thread(void *unused)
3190 test_malloc = kmalloc(1234, GFP_KERNEL);
3192 pr_info("failed to kmalloc\n");
3194 schedule_on_each_cpu(test_work);
3198 set_current_state(TASK_INTERRUPTIBLE);
3199 while (!kthread_should_stop()) {
3201 set_current_state(TASK_INTERRUPTIBLE);
3203 __set_current_state(TASK_RUNNING);
3209 * Do various things that may trigger events.
3211 static __init void event_test_stuff(void)
3213 struct task_struct *test_thread;
3215 test_thread = kthread_run(event_test_thread, NULL, "test-events");
3217 kthread_stop(test_thread);
3221 * For every trace event defined, we will test each trace point separately,
3222 * and then by groups, and finally all trace points.
3224 static __init void event_trace_self_tests(void)
3226 struct trace_subsystem_dir *dir;
3227 struct trace_event_file *file;
3228 struct trace_event_call *call;
3229 struct event_subsystem *system;
3230 struct trace_array *tr;
3233 tr = top_trace_array();
3237 pr_info("Running tests on trace events:\n");
3239 list_for_each_entry(file, &tr->events, list) {
3241 call = file->event_call;
3243 /* Only test those that have a probe */
3244 if (!call->class || !call->class->probe)
3248 * Testing syscall events here is pretty useless, but
3249 * we still do it if configured. But this is time consuming.
3250 * What we really need is a user thread to perform the
3251 * syscalls as we test.
3253 #ifndef CONFIG_EVENT_TRACE_TEST_SYSCALLS
3254 if (call->class->system &&
3255 strcmp(call->class->system, "syscalls") == 0)
3259 pr_info("Testing event %s: ", trace_event_name(call));
3262 * If an event is already enabled, someone is using
3263 * it and the self test should not be on.
3265 if (file->flags & EVENT_FILE_FL_ENABLED) {
3266 pr_warn("Enabled event during self test!\n");
3271 ftrace_event_enable_disable(file, 1);
3273 ftrace_event_enable_disable(file, 0);
3278 /* Now test at the sub system level */
3280 pr_info("Running tests on trace event systems:\n");
3282 list_for_each_entry(dir, &tr->systems, list) {
3284 system = dir->subsystem;
3286 /* the ftrace system is special, skip it */
3287 if (strcmp(system->name, "ftrace") == 0)
3290 pr_info("Testing event system %s: ", system->name);
3292 ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 1);
3293 if (WARN_ON_ONCE(ret)) {
3294 pr_warn("error enabling system %s\n",
3301 ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 0);
3302 if (WARN_ON_ONCE(ret)) {
3303 pr_warn("error disabling system %s\n",
3311 /* Test with all events enabled */
3313 pr_info("Running tests on all trace events:\n");
3314 pr_info("Testing all events: ");
3316 ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 1);
3317 if (WARN_ON_ONCE(ret)) {
3318 pr_warn("error enabling all events\n");
3325 ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 0);
3326 if (WARN_ON_ONCE(ret)) {
3327 pr_warn("error disabling all events\n");
3334 #ifdef CONFIG_FUNCTION_TRACER
3336 static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable);
3338 static struct trace_array *event_tr;
3341 function_test_events_call(unsigned long ip, unsigned long parent_ip,
3342 struct ftrace_ops *op, struct pt_regs *pt_regs)
3344 struct ring_buffer_event *event;
3345 struct ring_buffer *buffer;
3346 struct ftrace_entry *entry;
3347 unsigned long flags;
3352 pc = preempt_count();
3353 preempt_disable_notrace();
3354 cpu = raw_smp_processor_id();
3355 disabled = atomic_inc_return(&per_cpu(ftrace_test_event_disable, cpu));
3360 local_save_flags(flags);
3362 event = trace_current_buffer_lock_reserve(&buffer,
3363 TRACE_FN, sizeof(*entry),
3367 entry = ring_buffer_event_data(event);
3369 entry->parent_ip = parent_ip;
3371 trace_buffer_unlock_commit(event_tr, buffer, event, flags, pc);
3374 atomic_dec(&per_cpu(ftrace_test_event_disable, cpu));
3375 preempt_enable_notrace();
3378 static struct ftrace_ops trace_ops __initdata =
3380 .func = function_test_events_call,
3381 .flags = FTRACE_OPS_FL_RECURSION_SAFE,
3384 static __init void event_trace_self_test_with_function(void)
3387 event_tr = top_trace_array();
3388 if (WARN_ON(!event_tr))
3390 ret = register_ftrace_function(&trace_ops);
3391 if (WARN_ON(ret < 0)) {
3392 pr_info("Failed to enable function tracer for event tests\n");
3395 pr_info("Running tests again, along with the function tracer\n");
3396 event_trace_self_tests();
3397 unregister_ftrace_function(&trace_ops);
3400 static __init void event_trace_self_test_with_function(void)
3405 static __init int event_trace_self_tests_init(void)
3407 if (!tracing_selftest_disabled) {
3408 event_trace_self_tests();
3409 event_trace_self_test_with_function();
3415 late_initcall(event_trace_self_tests_init);