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 #include <linux/workqueue.h>
12 #include <linux/spinlock.h>
13 #include <linux/kthread.h>
14 #include <linux/debugfs.h>
15 #include <linux/uaccess.h>
16 #include <linux/module.h>
17 #include <linux/ctype.h>
18 #include <linux/slab.h>
19 #include <linux/delay.h>
21 #include <asm/setup.h>
23 #include "trace_output.h"
26 #define TRACE_SYSTEM "TRACE_SYSTEM"
28 DEFINE_MUTEX(event_mutex
);
30 LIST_HEAD(ftrace_events
);
32 #define COMMON_FIELD_COUNT 5
35 trace_get_fields(struct ftrace_event_call
*event_call
)
37 if (!event_call
->class->get_fields
)
38 return &event_call
->class->fields
;
39 return event_call
->class->get_fields(event_call
);
42 int trace_define_field(struct ftrace_event_call
*call
, const char *type
,
43 const char *name
, int offset
, int size
, int is_signed
,
46 struct ftrace_event_field
*field
;
47 struct list_head
*head
;
49 if (WARN_ON(!call
->class))
52 field
= kzalloc(sizeof(*field
), GFP_KERNEL
);
56 field
->name
= kstrdup(name
, GFP_KERNEL
);
60 field
->type
= kstrdup(type
, GFP_KERNEL
);
64 if (filter_type
== FILTER_OTHER
)
65 field
->filter_type
= filter_assign_type(type
);
67 field
->filter_type
= filter_type
;
69 field
->offset
= offset
;
71 field
->is_signed
= is_signed
;
73 head
= trace_get_fields(call
);
74 list_add(&field
->link
, head
);
85 EXPORT_SYMBOL_GPL(trace_define_field
);
87 #define __common_field(type, item) \
88 ret = trace_define_field(call, #type, "common_" #item, \
89 offsetof(typeof(ent), item), \
91 is_signed_type(type), FILTER_OTHER); \
95 static int trace_define_common_fields(struct ftrace_event_call
*call
)
98 struct trace_entry ent
;
100 __common_field(unsigned short, type
);
101 __common_field(unsigned char, flags
);
102 __common_field(unsigned char, preempt_count
);
103 __common_field(int, pid
);
104 __common_field(int, lock_depth
);
109 void trace_destroy_fields(struct ftrace_event_call
*call
)
111 struct ftrace_event_field
*field
, *next
;
112 struct list_head
*head
;
114 head
= trace_get_fields(call
);
115 list_for_each_entry_safe(field
, next
, head
, link
) {
116 list_del(&field
->link
);
123 int trace_event_raw_init(struct ftrace_event_call
*call
)
127 id
= register_ftrace_event(&call
->event
);
133 EXPORT_SYMBOL_GPL(trace_event_raw_init
);
135 static int ftrace_event_enable_disable(struct ftrace_event_call
*call
,
142 if (call
->flags
& TRACE_EVENT_FL_ENABLED
) {
143 call
->flags
&= ~TRACE_EVENT_FL_ENABLED
;
144 tracing_stop_cmdline_record();
145 if (call
->class->reg
)
146 call
->class->reg(call
, TRACE_REG_UNREGISTER
);
148 tracepoint_probe_unregister(call
->name
,
154 if (!(call
->flags
& TRACE_EVENT_FL_ENABLED
)) {
155 tracing_start_cmdline_record();
156 if (call
->class->reg
)
157 ret
= call
->class->reg(call
, TRACE_REG_REGISTER
);
159 ret
= tracepoint_probe_register(call
->name
,
163 tracing_stop_cmdline_record();
164 pr_info("event trace: Could not enable event "
168 call
->flags
|= TRACE_EVENT_FL_ENABLED
;
176 static void ftrace_clear_events(void)
178 struct ftrace_event_call
*call
;
180 mutex_lock(&event_mutex
);
181 list_for_each_entry(call
, &ftrace_events
, list
) {
182 ftrace_event_enable_disable(call
, 0);
184 mutex_unlock(&event_mutex
);
188 * __ftrace_set_clr_event(NULL, NULL, NULL, set) will set/unset all events.
190 static int __ftrace_set_clr_event(const char *match
, const char *sub
,
191 const char *event
, int set
)
193 struct ftrace_event_call
*call
;
196 mutex_lock(&event_mutex
);
197 list_for_each_entry(call
, &ftrace_events
, list
) {
199 if (!call
->name
|| !call
->class ||
200 (!call
->class->probe
&& !call
->class->reg
))
204 strcmp(match
, call
->name
) != 0 &&
205 strcmp(match
, call
->class->system
) != 0)
208 if (sub
&& strcmp(sub
, call
->class->system
) != 0)
211 if (event
&& strcmp(event
, call
->name
) != 0)
214 ftrace_event_enable_disable(call
, set
);
218 mutex_unlock(&event_mutex
);
223 static int ftrace_set_clr_event(char *buf
, int set
)
225 char *event
= NULL
, *sub
= NULL
, *match
;
228 * The buf format can be <subsystem>:<event-name>
229 * *:<event-name> means any event by that name.
230 * :<event-name> is the same.
232 * <subsystem>:* means all events in that subsystem
233 * <subsystem>: means the same.
235 * <name> (no ':') means all events in a subsystem with
236 * the name <name> or any event that matches <name>
239 match
= strsep(&buf
, ":");
245 if (!strlen(sub
) || strcmp(sub
, "*") == 0)
247 if (!strlen(event
) || strcmp(event
, "*") == 0)
251 return __ftrace_set_clr_event(match
, sub
, event
, set
);
255 * trace_set_clr_event - enable or disable an event
256 * @system: system name to match (NULL for any system)
257 * @event: event name to match (NULL for all events, within system)
258 * @set: 1 to enable, 0 to disable
260 * This is a way for other parts of the kernel to enable or disable
263 * Returns 0 on success, -EINVAL if the parameters do not match any
266 int trace_set_clr_event(const char *system
, const char *event
, int set
)
268 return __ftrace_set_clr_event(NULL
, system
, event
, set
);
271 /* 128 should be much more than enough */
272 #define EVENT_BUF_SIZE 127
275 ftrace_event_write(struct file
*file
, const char __user
*ubuf
,
276 size_t cnt
, loff_t
*ppos
)
278 struct trace_parser parser
;
284 ret
= tracing_update_buffers();
288 if (trace_parser_get_init(&parser
, EVENT_BUF_SIZE
+ 1))
291 read
= trace_get_user(&parser
, ubuf
, cnt
, ppos
);
293 if (read
>= 0 && trace_parser_loaded((&parser
))) {
296 if (*parser
.buffer
== '!')
299 parser
.buffer
[parser
.idx
] = 0;
301 ret
= ftrace_set_clr_event(parser
.buffer
+ !set
, set
);
309 trace_parser_put(&parser
);
315 t_next(struct seq_file
*m
, void *v
, loff_t
*pos
)
317 struct ftrace_event_call
*call
= v
;
321 list_for_each_entry_continue(call
, &ftrace_events
, list
) {
323 * The ftrace subsystem is for showing formats only.
324 * They can not be enabled or disabled via the event files.
326 if (call
->class && (call
->class->probe
|| call
->class->reg
))
333 static void *t_start(struct seq_file
*m
, loff_t
*pos
)
335 struct ftrace_event_call
*call
;
338 mutex_lock(&event_mutex
);
340 call
= list_entry(&ftrace_events
, struct ftrace_event_call
, list
);
341 for (l
= 0; l
<= *pos
; ) {
342 call
= t_next(m
, call
, &l
);
350 s_next(struct seq_file
*m
, void *v
, loff_t
*pos
)
352 struct ftrace_event_call
*call
= v
;
356 list_for_each_entry_continue(call
, &ftrace_events
, list
) {
357 if (call
->flags
& TRACE_EVENT_FL_ENABLED
)
364 static void *s_start(struct seq_file
*m
, loff_t
*pos
)
366 struct ftrace_event_call
*call
;
369 mutex_lock(&event_mutex
);
371 call
= list_entry(&ftrace_events
, struct ftrace_event_call
, list
);
372 for (l
= 0; l
<= *pos
; ) {
373 call
= s_next(m
, call
, &l
);
380 static int t_show(struct seq_file
*m
, void *v
)
382 struct ftrace_event_call
*call
= v
;
384 if (strcmp(call
->class->system
, TRACE_SYSTEM
) != 0)
385 seq_printf(m
, "%s:", call
->class->system
);
386 seq_printf(m
, "%s\n", call
->name
);
391 static void t_stop(struct seq_file
*m
, void *p
)
393 mutex_unlock(&event_mutex
);
397 ftrace_event_seq_open(struct inode
*inode
, struct file
*file
)
399 const struct seq_operations
*seq_ops
;
401 if ((file
->f_mode
& FMODE_WRITE
) &&
402 (file
->f_flags
& O_TRUNC
))
403 ftrace_clear_events();
405 seq_ops
= inode
->i_private
;
406 return seq_open(file
, seq_ops
);
410 event_enable_read(struct file
*filp
, char __user
*ubuf
, size_t cnt
,
413 struct ftrace_event_call
*call
= filp
->private_data
;
416 if (call
->flags
& TRACE_EVENT_FL_ENABLED
)
421 return simple_read_from_buffer(ubuf
, cnt
, ppos
, buf
, 2);
425 event_enable_write(struct file
*filp
, const char __user
*ubuf
, size_t cnt
,
428 struct ftrace_event_call
*call
= filp
->private_data
;
433 if (cnt
>= sizeof(buf
))
436 if (copy_from_user(&buf
, ubuf
, cnt
))
441 ret
= strict_strtoul(buf
, 10, &val
);
445 ret
= tracing_update_buffers();
452 mutex_lock(&event_mutex
);
453 ret
= ftrace_event_enable_disable(call
, val
);
454 mutex_unlock(&event_mutex
);
463 return ret
? ret
: cnt
;
467 system_enable_read(struct file
*filp
, char __user
*ubuf
, size_t cnt
,
470 const char set_to_char
[4] = { '?', '0', '1', 'X' };
471 const char *system
= filp
->private_data
;
472 struct ftrace_event_call
*call
;
477 mutex_lock(&event_mutex
);
478 list_for_each_entry(call
, &ftrace_events
, list
) {
479 if (!call
->name
|| !call
->class ||
480 (!call
->class->probe
&& !call
->class->reg
))
483 if (system
&& strcmp(call
->class->system
, system
) != 0)
487 * We need to find out if all the events are set
488 * or if all events or cleared, or if we have
491 set
|= (1 << !!(call
->flags
& TRACE_EVENT_FL_ENABLED
));
494 * If we have a mixture, no need to look further.
499 mutex_unlock(&event_mutex
);
501 buf
[0] = set_to_char
[set
];
504 ret
= simple_read_from_buffer(ubuf
, cnt
, ppos
, buf
, 2);
510 system_enable_write(struct file
*filp
, const char __user
*ubuf
, size_t cnt
,
513 const char *system
= filp
->private_data
;
518 if (cnt
>= sizeof(buf
))
521 if (copy_from_user(&buf
, ubuf
, cnt
))
526 ret
= strict_strtoul(buf
, 10, &val
);
530 ret
= tracing_update_buffers();
534 if (val
!= 0 && val
!= 1)
537 ret
= __ftrace_set_clr_event(NULL
, system
, NULL
, val
);
554 static void *f_next(struct seq_file
*m
, void *v
, loff_t
*pos
)
556 struct ftrace_event_call
*call
= m
->private;
557 struct ftrace_event_field
*field
;
558 struct list_head
*head
;
563 head
= trace_get_fields(call
);
565 switch ((unsigned long)v
) {
568 if (unlikely(list_empty(head
)))
571 field
= list_entry(head
->prev
, struct ftrace_event_field
, link
);
574 case FORMAT_PRINTFMT
:
580 * To separate common fields from event fields, the
581 * LSB is set on the first event field. Clear it in case.
583 v
= (void *)((unsigned long)v
& ~1L);
586 if (field
->link
.prev
== head
)
587 return (void *)FORMAT_PRINTFMT
;
589 field
= list_entry(field
->link
.prev
, struct ftrace_event_field
, link
);
591 /* Set the LSB to notify f_show to print an extra newline */
592 if (index
== COMMON_FIELD_COUNT
)
593 field
= (struct ftrace_event_field
*)
594 ((unsigned long)field
| 1);
599 static void *f_start(struct seq_file
*m
, loff_t
*pos
)
604 /* Start by showing the header */
606 return (void *)FORMAT_HEADER
;
608 p
= (void *)FORMAT_HEADER
;
610 p
= f_next(m
, p
, &l
);
611 } while (p
&& l
< *pos
);
616 static int f_show(struct seq_file
*m
, void *v
)
618 struct ftrace_event_call
*call
= m
->private;
619 struct ftrace_event_field
*field
;
620 const char *array_descriptor
;
622 switch ((unsigned long)v
) {
624 seq_printf(m
, "name: %s\n", call
->name
);
625 seq_printf(m
, "ID: %d\n", call
->event
.type
);
626 seq_printf(m
, "format:\n");
629 case FORMAT_PRINTFMT
:
630 seq_printf(m
, "\nprint fmt: %s\n",
636 * To separate common fields from event fields, the
637 * LSB is set on the first event field. Clear it and
638 * print a newline if it is set.
640 if ((unsigned long)v
& 1) {
642 v
= (void *)((unsigned long)v
& ~1L);
648 * Smartly shows the array type(except dynamic array).
651 * If TYPE := TYPE[LEN], it is shown:
652 * field:TYPE VAR[LEN]
654 array_descriptor
= strchr(field
->type
, '[');
656 if (!strncmp(field
->type
, "__data_loc", 10))
657 array_descriptor
= NULL
;
659 if (!array_descriptor
)
660 seq_printf(m
, "\tfield:%s %s;\toffset:%u;\tsize:%u;\tsigned:%d;\n",
661 field
->type
, field
->name
, field
->offset
,
662 field
->size
, !!field
->is_signed
);
664 seq_printf(m
, "\tfield:%.*s %s%s;\toffset:%u;\tsize:%u;\tsigned:%d;\n",
665 (int)(array_descriptor
- field
->type
),
666 field
->type
, field
->name
,
667 array_descriptor
, field
->offset
,
668 field
->size
, !!field
->is_signed
);
673 static void f_stop(struct seq_file
*m
, void *p
)
677 static const struct seq_operations trace_format_seq_ops
= {
684 static int trace_format_open(struct inode
*inode
, struct file
*file
)
686 struct ftrace_event_call
*call
= inode
->i_private
;
690 ret
= seq_open(file
, &trace_format_seq_ops
);
694 m
= file
->private_data
;
701 event_id_read(struct file
*filp
, char __user
*ubuf
, size_t cnt
, loff_t
*ppos
)
703 struct ftrace_event_call
*call
= filp
->private_data
;
710 s
= kmalloc(sizeof(*s
), GFP_KERNEL
);
715 trace_seq_printf(s
, "%d\n", call
->event
.type
);
717 r
= simple_read_from_buffer(ubuf
, cnt
, ppos
,
724 event_filter_read(struct file
*filp
, char __user
*ubuf
, size_t cnt
,
727 struct ftrace_event_call
*call
= filp
->private_data
;
734 s
= kmalloc(sizeof(*s
), GFP_KERNEL
);
740 print_event_filter(call
, s
);
741 r
= simple_read_from_buffer(ubuf
, cnt
, ppos
, s
->buffer
, s
->len
);
749 event_filter_write(struct file
*filp
, const char __user
*ubuf
, size_t cnt
,
752 struct ftrace_event_call
*call
= filp
->private_data
;
756 if (cnt
>= PAGE_SIZE
)
759 buf
= (char *)__get_free_page(GFP_TEMPORARY
);
763 if (copy_from_user(buf
, ubuf
, cnt
)) {
764 free_page((unsigned long) buf
);
769 err
= apply_event_filter(call
, buf
);
770 free_page((unsigned long) buf
);
780 subsystem_filter_read(struct file
*filp
, char __user
*ubuf
, size_t cnt
,
783 struct event_subsystem
*system
= filp
->private_data
;
790 s
= kmalloc(sizeof(*s
), GFP_KERNEL
);
796 print_subsystem_event_filter(system
, s
);
797 r
= simple_read_from_buffer(ubuf
, cnt
, ppos
, s
->buffer
, s
->len
);
805 subsystem_filter_write(struct file
*filp
, const char __user
*ubuf
, size_t cnt
,
808 struct event_subsystem
*system
= filp
->private_data
;
812 if (cnt
>= PAGE_SIZE
)
815 buf
= (char *)__get_free_page(GFP_TEMPORARY
);
819 if (copy_from_user(buf
, ubuf
, cnt
)) {
820 free_page((unsigned long) buf
);
825 err
= apply_subsystem_event_filter(system
, buf
);
826 free_page((unsigned long) buf
);
836 show_header(struct file
*filp
, char __user
*ubuf
, size_t cnt
, loff_t
*ppos
)
838 int (*func
)(struct trace_seq
*s
) = filp
->private_data
;
845 s
= kmalloc(sizeof(*s
), GFP_KERNEL
);
852 r
= simple_read_from_buffer(ubuf
, cnt
, ppos
, s
->buffer
, s
->len
);
859 static const struct seq_operations show_event_seq_ops
= {
866 static const struct seq_operations show_set_event_seq_ops
= {
873 static const struct file_operations ftrace_avail_fops
= {
874 .open
= ftrace_event_seq_open
,
877 .release
= seq_release
,
880 static const struct file_operations ftrace_set_event_fops
= {
881 .open
= ftrace_event_seq_open
,
883 .write
= ftrace_event_write
,
885 .release
= seq_release
,
888 static const struct file_operations ftrace_enable_fops
= {
889 .open
= tracing_open_generic
,
890 .read
= event_enable_read
,
891 .write
= event_enable_write
,
894 static const struct file_operations ftrace_event_format_fops
= {
895 .open
= trace_format_open
,
898 .release
= seq_release
,
901 static const struct file_operations ftrace_event_id_fops
= {
902 .open
= tracing_open_generic
,
903 .read
= event_id_read
,
906 static const struct file_operations ftrace_event_filter_fops
= {
907 .open
= tracing_open_generic
,
908 .read
= event_filter_read
,
909 .write
= event_filter_write
,
912 static const struct file_operations ftrace_subsystem_filter_fops
= {
913 .open
= tracing_open_generic
,
914 .read
= subsystem_filter_read
,
915 .write
= subsystem_filter_write
,
918 static const struct file_operations ftrace_system_enable_fops
= {
919 .open
= tracing_open_generic
,
920 .read
= system_enable_read
,
921 .write
= system_enable_write
,
924 static const struct file_operations ftrace_show_header_fops
= {
925 .open
= tracing_open_generic
,
929 static struct dentry
*event_trace_events_dir(void)
931 static struct dentry
*d_tracer
;
932 static struct dentry
*d_events
;
937 d_tracer
= tracing_init_dentry();
941 d_events
= debugfs_create_dir("events", d_tracer
);
943 pr_warning("Could not create debugfs "
944 "'events' directory\n");
949 static LIST_HEAD(event_subsystems
);
951 static struct dentry
*
952 event_subsystem_dir(const char *name
, struct dentry
*d_events
)
954 struct event_subsystem
*system
;
955 struct dentry
*entry
;
957 /* First see if we did not already create this dir */
958 list_for_each_entry(system
, &event_subsystems
, list
) {
959 if (strcmp(system
->name
, name
) == 0) {
961 return system
->entry
;
965 /* need to create new entry */
966 system
= kmalloc(sizeof(*system
), GFP_KERNEL
);
968 pr_warning("No memory to create event subsystem %s\n",
973 system
->entry
= debugfs_create_dir(name
, d_events
);
974 if (!system
->entry
) {
975 pr_warning("Could not create event subsystem %s\n",
981 system
->nr_events
= 1;
982 system
->name
= kstrdup(name
, GFP_KERNEL
);
984 debugfs_remove(system
->entry
);
989 list_add(&system
->list
, &event_subsystems
);
991 system
->filter
= NULL
;
993 system
->filter
= kzalloc(sizeof(struct event_filter
), GFP_KERNEL
);
994 if (!system
->filter
) {
995 pr_warning("Could not allocate filter for subsystem "
997 return system
->entry
;
1000 entry
= debugfs_create_file("filter", 0644, system
->entry
, system
,
1001 &ftrace_subsystem_filter_fops
);
1003 kfree(system
->filter
);
1004 system
->filter
= NULL
;
1005 pr_warning("Could not create debugfs "
1006 "'%s/filter' entry\n", name
);
1009 trace_create_file("enable", 0644, system
->entry
,
1010 (void *)system
->name
,
1011 &ftrace_system_enable_fops
);
1013 return system
->entry
;
1017 event_create_dir(struct ftrace_event_call
*call
, struct dentry
*d_events
,
1018 const struct file_operations
*id
,
1019 const struct file_operations
*enable
,
1020 const struct file_operations
*filter
,
1021 const struct file_operations
*format
)
1023 struct list_head
*head
;
1027 * If the trace point header did not define TRACE_SYSTEM
1028 * then the system would be called "TRACE_SYSTEM".
1030 if (strcmp(call
->class->system
, TRACE_SYSTEM
) != 0)
1031 d_events
= event_subsystem_dir(call
->class->system
, d_events
);
1033 call
->dir
= debugfs_create_dir(call
->name
, d_events
);
1035 pr_warning("Could not create debugfs "
1036 "'%s' directory\n", call
->name
);
1040 if (call
->class->probe
|| call
->class->reg
)
1041 trace_create_file("enable", 0644, call
->dir
, call
,
1044 #ifdef CONFIG_PERF_EVENTS
1045 if (call
->event
.type
&& (call
->class->perf_probe
|| call
->class->reg
))
1046 trace_create_file("id", 0444, call
->dir
, call
,
1050 if (call
->class->define_fields
) {
1052 * Other events may have the same class. Only update
1053 * the fields if they are not already defined.
1055 head
= trace_get_fields(call
);
1056 if (list_empty(head
)) {
1057 ret
= trace_define_common_fields(call
);
1059 ret
= call
->class->define_fields(call
);
1061 pr_warning("Could not initialize trace point"
1062 " events/%s\n", call
->name
);
1066 trace_create_file("filter", 0644, call
->dir
, call
,
1070 trace_create_file("format", 0444, call
->dir
, call
,
1076 static int __trace_add_event_call(struct ftrace_event_call
*call
)
1078 struct dentry
*d_events
;
1084 if (call
->class->raw_init
) {
1085 ret
= call
->class->raw_init(call
);
1088 pr_warning("Could not initialize trace "
1089 "events/%s\n", call
->name
);
1094 d_events
= event_trace_events_dir();
1098 ret
= event_create_dir(call
, d_events
, &ftrace_event_id_fops
,
1099 &ftrace_enable_fops
, &ftrace_event_filter_fops
,
1100 &ftrace_event_format_fops
);
1102 list_add(&call
->list
, &ftrace_events
);
1107 /* Add an additional event_call dynamically */
1108 int trace_add_event_call(struct ftrace_event_call
*call
)
1111 mutex_lock(&event_mutex
);
1112 ret
= __trace_add_event_call(call
);
1113 mutex_unlock(&event_mutex
);
1117 static void remove_subsystem_dir(const char *name
)
1119 struct event_subsystem
*system
;
1121 if (strcmp(name
, TRACE_SYSTEM
) == 0)
1124 list_for_each_entry(system
, &event_subsystems
, list
) {
1125 if (strcmp(system
->name
, name
) == 0) {
1126 if (!--system
->nr_events
) {
1127 struct event_filter
*filter
= system
->filter
;
1129 debugfs_remove_recursive(system
->entry
);
1130 list_del(&system
->list
);
1132 kfree(filter
->filter_string
);
1135 kfree(system
->name
);
1144 * Must be called under locking both of event_mutex and trace_event_mutex.
1146 static void __trace_remove_event_call(struct ftrace_event_call
*call
)
1148 ftrace_event_enable_disable(call
, 0);
1149 if (call
->event
.funcs
)
1150 __unregister_ftrace_event(&call
->event
);
1151 debugfs_remove_recursive(call
->dir
);
1152 list_del(&call
->list
);
1153 trace_destroy_fields(call
);
1154 destroy_preds(call
);
1155 remove_subsystem_dir(call
->class->system
);
1158 /* Remove an event_call */
1159 void trace_remove_event_call(struct ftrace_event_call
*call
)
1161 mutex_lock(&event_mutex
);
1162 down_write(&trace_event_mutex
);
1163 __trace_remove_event_call(call
);
1164 up_write(&trace_event_mutex
);
1165 mutex_unlock(&event_mutex
);
1168 #define for_each_event(event, start, end) \
1169 for (event = start; \
1170 (unsigned long)event < (unsigned long)end; \
1173 #ifdef CONFIG_MODULES
1175 static LIST_HEAD(ftrace_module_file_list
);
1178 * Modules must own their file_operations to keep up with
1179 * reference counting.
1181 struct ftrace_module_file_ops
{
1182 struct list_head list
;
1184 struct file_operations id
;
1185 struct file_operations enable
;
1186 struct file_operations format
;
1187 struct file_operations filter
;
1190 static struct ftrace_module_file_ops
*
1191 trace_create_file_ops(struct module
*mod
)
1193 struct ftrace_module_file_ops
*file_ops
;
1196 * This is a bit of a PITA. To allow for correct reference
1197 * counting, modules must "own" their file_operations.
1198 * To do this, we allocate the file operations that will be
1199 * used in the event directory.
1202 file_ops
= kmalloc(sizeof(*file_ops
), GFP_KERNEL
);
1206 file_ops
->mod
= mod
;
1208 file_ops
->id
= ftrace_event_id_fops
;
1209 file_ops
->id
.owner
= mod
;
1211 file_ops
->enable
= ftrace_enable_fops
;
1212 file_ops
->enable
.owner
= mod
;
1214 file_ops
->filter
= ftrace_event_filter_fops
;
1215 file_ops
->filter
.owner
= mod
;
1217 file_ops
->format
= ftrace_event_format_fops
;
1218 file_ops
->format
.owner
= mod
;
1220 list_add(&file_ops
->list
, &ftrace_module_file_list
);
1225 static void trace_module_add_events(struct module
*mod
)
1227 struct ftrace_module_file_ops
*file_ops
= NULL
;
1228 struct ftrace_event_call
*call
, *start
, *end
;
1229 struct dentry
*d_events
;
1232 start
= mod
->trace_events
;
1233 end
= mod
->trace_events
+ mod
->num_trace_events
;
1238 d_events
= event_trace_events_dir();
1242 for_each_event(call
, start
, end
) {
1243 /* The linker may leave blanks */
1246 if (call
->class->raw_init
) {
1247 ret
= call
->class->raw_init(call
);
1250 pr_warning("Could not initialize trace "
1251 "point events/%s\n", call
->name
);
1256 * This module has events, create file ops for this module
1257 * if not already done.
1260 file_ops
= trace_create_file_ops(mod
);
1265 ret
= event_create_dir(call
, d_events
,
1266 &file_ops
->id
, &file_ops
->enable
,
1267 &file_ops
->filter
, &file_ops
->format
);
1269 list_add(&call
->list
, &ftrace_events
);
1273 static void trace_module_remove_events(struct module
*mod
)
1275 struct ftrace_module_file_ops
*file_ops
;
1276 struct ftrace_event_call
*call
, *p
;
1279 down_write(&trace_event_mutex
);
1280 list_for_each_entry_safe(call
, p
, &ftrace_events
, list
) {
1281 if (call
->mod
== mod
) {
1283 __trace_remove_event_call(call
);
1287 /* Now free the file_operations */
1288 list_for_each_entry(file_ops
, &ftrace_module_file_list
, list
) {
1289 if (file_ops
->mod
== mod
)
1292 if (&file_ops
->list
!= &ftrace_module_file_list
) {
1293 list_del(&file_ops
->list
);
1298 * It is safest to reset the ring buffer if the module being unloaded
1299 * registered any events.
1302 tracing_reset_current_online_cpus();
1303 up_write(&trace_event_mutex
);
1306 static int trace_module_notify(struct notifier_block
*self
,
1307 unsigned long val
, void *data
)
1309 struct module
*mod
= data
;
1311 mutex_lock(&event_mutex
);
1313 case MODULE_STATE_COMING
:
1314 trace_module_add_events(mod
);
1316 case MODULE_STATE_GOING
:
1317 trace_module_remove_events(mod
);
1320 mutex_unlock(&event_mutex
);
1325 static int trace_module_notify(struct notifier_block
*self
,
1326 unsigned long val
, void *data
)
1330 #endif /* CONFIG_MODULES */
1332 static struct notifier_block trace_module_nb
= {
1333 .notifier_call
= trace_module_notify
,
1337 extern struct ftrace_event_call __start_ftrace_events
[];
1338 extern struct ftrace_event_call __stop_ftrace_events
[];
1340 static char bootup_event_buf
[COMMAND_LINE_SIZE
] __initdata
;
1342 static __init
int setup_trace_event(char *str
)
1344 strlcpy(bootup_event_buf
, str
, COMMAND_LINE_SIZE
);
1345 ring_buffer_expanded
= 1;
1346 tracing_selftest_disabled
= 1;
1350 __setup("trace_event=", setup_trace_event
);
1352 static __init
int event_trace_init(void)
1354 struct ftrace_event_call
*call
;
1355 struct dentry
*d_tracer
;
1356 struct dentry
*entry
;
1357 struct dentry
*d_events
;
1359 char *buf
= bootup_event_buf
;
1362 d_tracer
= tracing_init_dentry();
1366 entry
= debugfs_create_file("available_events", 0444, d_tracer
,
1367 (void *)&show_event_seq_ops
,
1368 &ftrace_avail_fops
);
1370 pr_warning("Could not create debugfs "
1371 "'available_events' entry\n");
1373 entry
= debugfs_create_file("set_event", 0644, d_tracer
,
1374 (void *)&show_set_event_seq_ops
,
1375 &ftrace_set_event_fops
);
1377 pr_warning("Could not create debugfs "
1378 "'set_event' entry\n");
1380 d_events
= event_trace_events_dir();
1384 /* ring buffer internal formats */
1385 trace_create_file("header_page", 0444, d_events
,
1386 ring_buffer_print_page_header
,
1387 &ftrace_show_header_fops
);
1389 trace_create_file("header_event", 0444, d_events
,
1390 ring_buffer_print_entry_header
,
1391 &ftrace_show_header_fops
);
1393 trace_create_file("enable", 0644, d_events
,
1394 NULL
, &ftrace_system_enable_fops
);
1396 for_each_event(call
, __start_ftrace_events
, __stop_ftrace_events
) {
1397 /* The linker may leave blanks */
1400 if (call
->class->raw_init
) {
1401 ret
= call
->class->raw_init(call
);
1404 pr_warning("Could not initialize trace "
1405 "point events/%s\n", call
->name
);
1409 ret
= event_create_dir(call
, d_events
, &ftrace_event_id_fops
,
1410 &ftrace_enable_fops
,
1411 &ftrace_event_filter_fops
,
1412 &ftrace_event_format_fops
);
1414 list_add(&call
->list
, &ftrace_events
);
1418 token
= strsep(&buf
, ",");
1425 ret
= ftrace_set_clr_event(token
, 1);
1427 pr_warning("Failed to enable trace event: %s\n", token
);
1430 ret
= register_module_notifier(&trace_module_nb
);
1432 pr_warning("Failed to register trace events module notifier\n");
1436 fs_initcall(event_trace_init
);
1438 #ifdef CONFIG_FTRACE_STARTUP_TEST
1440 static DEFINE_SPINLOCK(test_spinlock
);
1441 static DEFINE_SPINLOCK(test_spinlock_irq
);
1442 static DEFINE_MUTEX(test_mutex
);
1444 static __init
void test_work(struct work_struct
*dummy
)
1446 spin_lock(&test_spinlock
);
1447 spin_lock_irq(&test_spinlock_irq
);
1449 spin_unlock_irq(&test_spinlock_irq
);
1450 spin_unlock(&test_spinlock
);
1452 mutex_lock(&test_mutex
);
1454 mutex_unlock(&test_mutex
);
1457 static __init
int event_test_thread(void *unused
)
1461 test_malloc
= kmalloc(1234, GFP_KERNEL
);
1463 pr_info("failed to kmalloc\n");
1465 schedule_on_each_cpu(test_work
);
1469 set_current_state(TASK_INTERRUPTIBLE
);
1470 while (!kthread_should_stop())
1477 * Do various things that may trigger events.
1479 static __init
void event_test_stuff(void)
1481 struct task_struct
*test_thread
;
1483 test_thread
= kthread_run(event_test_thread
, NULL
, "test-events");
1485 kthread_stop(test_thread
);
1489 * For every trace event defined, we will test each trace point separately,
1490 * and then by groups, and finally all trace points.
1492 static __init
void event_trace_self_tests(void)
1494 struct ftrace_event_call
*call
;
1495 struct event_subsystem
*system
;
1498 pr_info("Running tests on trace events:\n");
1500 list_for_each_entry(call
, &ftrace_events
, list
) {
1502 /* Only test those that have a probe */
1503 if (!call
->class || !call
->class->probe
)
1507 * Testing syscall events here is pretty useless, but
1508 * we still do it if configured. But this is time consuming.
1509 * What we really need is a user thread to perform the
1510 * syscalls as we test.
1512 #ifndef CONFIG_EVENT_TRACE_TEST_SYSCALLS
1513 if (call
->class->system
&&
1514 strcmp(call
->class->system
, "syscalls") == 0)
1518 pr_info("Testing event %s: ", call
->name
);
1521 * If an event is already enabled, someone is using
1522 * it and the self test should not be on.
1524 if (call
->flags
& TRACE_EVENT_FL_ENABLED
) {
1525 pr_warning("Enabled event during self test!\n");
1530 ftrace_event_enable_disable(call
, 1);
1532 ftrace_event_enable_disable(call
, 0);
1537 /* Now test at the sub system level */
1539 pr_info("Running tests on trace event systems:\n");
1541 list_for_each_entry(system
, &event_subsystems
, list
) {
1543 /* the ftrace system is special, skip it */
1544 if (strcmp(system
->name
, "ftrace") == 0)
1547 pr_info("Testing event system %s: ", system
->name
);
1549 ret
= __ftrace_set_clr_event(NULL
, system
->name
, NULL
, 1);
1550 if (WARN_ON_ONCE(ret
)) {
1551 pr_warning("error enabling system %s\n",
1558 ret
= __ftrace_set_clr_event(NULL
, system
->name
, NULL
, 0);
1559 if (WARN_ON_ONCE(ret
))
1560 pr_warning("error disabling system %s\n",
1566 /* Test with all events enabled */
1568 pr_info("Running tests on all trace events:\n");
1569 pr_info("Testing all events: ");
1571 ret
= __ftrace_set_clr_event(NULL
, NULL
, NULL
, 1);
1572 if (WARN_ON_ONCE(ret
)) {
1573 pr_warning("error enabling all events\n");
1580 ret
= __ftrace_set_clr_event(NULL
, NULL
, NULL
, 0);
1581 if (WARN_ON_ONCE(ret
)) {
1582 pr_warning("error disabling all events\n");
1589 #ifdef CONFIG_FUNCTION_TRACER
1591 static DEFINE_PER_CPU(atomic_t
, ftrace_test_event_disable
);
1594 function_test_events_call(unsigned long ip
, unsigned long parent_ip
)
1596 struct ring_buffer_event
*event
;
1597 struct ring_buffer
*buffer
;
1598 struct ftrace_entry
*entry
;
1599 unsigned long flags
;
1605 pc
= preempt_count();
1606 resched
= ftrace_preempt_disable();
1607 cpu
= raw_smp_processor_id();
1608 disabled
= atomic_inc_return(&per_cpu(ftrace_test_event_disable
, cpu
));
1613 local_save_flags(flags
);
1615 event
= trace_current_buffer_lock_reserve(&buffer
,
1616 TRACE_FN
, sizeof(*entry
),
1620 entry
= ring_buffer_event_data(event
);
1622 entry
->parent_ip
= parent_ip
;
1624 trace_nowake_buffer_unlock_commit(buffer
, event
, flags
, pc
);
1627 atomic_dec(&per_cpu(ftrace_test_event_disable
, cpu
));
1628 ftrace_preempt_enable(resched
);
1631 static struct ftrace_ops trace_ops __initdata
=
1633 .func
= function_test_events_call
,
1636 static __init
void event_trace_self_test_with_function(void)
1638 register_ftrace_function(&trace_ops
);
1639 pr_info("Running tests again, along with the function tracer\n");
1640 event_trace_self_tests();
1641 unregister_ftrace_function(&trace_ops
);
1644 static __init
void event_trace_self_test_with_function(void)
1649 static __init
int event_trace_self_tests_init(void)
1651 if (!tracing_selftest_disabled
) {
1652 event_trace_self_tests();
1653 event_trace_self_test_with_function();
1659 late_initcall(event_trace_self_tests_init
);