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/delay.h>
20 #include <asm/setup.h>
22 #include "trace_output.h"
25 #define TRACE_SYSTEM "TRACE_SYSTEM"
27 DEFINE_MUTEX(event_mutex);
29 LIST_HEAD(ftrace_events);
31 int trace_define_field(struct ftrace_event_call *call, const char *type,
32 const char *name, int offset, int size, int is_signed,
35 struct ftrace_event_field *field;
37 field = kzalloc(sizeof(*field), GFP_KERNEL);
41 field->name = kstrdup(name, GFP_KERNEL);
45 field->type = kstrdup(type, GFP_KERNEL);
49 if (filter_type == FILTER_OTHER)
50 field->filter_type = filter_assign_type(type);
52 field->filter_type = filter_type;
54 field->offset = offset;
56 field->is_signed = is_signed;
58 list_add(&field->link, &call->fields);
71 EXPORT_SYMBOL_GPL(trace_define_field);
73 #define __common_field(type, item) \
74 ret = trace_define_field(call, #type, "common_" #item, \
75 offsetof(typeof(ent), item), \
77 is_signed_type(type), FILTER_OTHER); \
81 int trace_define_common_fields(struct ftrace_event_call *call)
84 struct trace_entry ent;
86 __common_field(unsigned short, type);
87 __common_field(unsigned char, flags);
88 __common_field(unsigned char, preempt_count);
89 __common_field(int, pid);
90 __common_field(int, lock_depth);
94 EXPORT_SYMBOL_GPL(trace_define_common_fields);
98 static void trace_destroy_fields(struct ftrace_event_call *call)
100 struct ftrace_event_field *field, *next;
102 list_for_each_entry_safe(field, next, &call->fields, link) {
103 list_del(&field->link);
110 #endif /* CONFIG_MODULES */
112 static void ftrace_event_enable_disable(struct ftrace_event_call *call,
119 tracing_stop_cmdline_record();
120 call->unregfunc(call->data);
124 if (!call->enabled) {
126 tracing_start_cmdline_record();
127 call->regfunc(call->data);
133 static void ftrace_clear_events(void)
135 struct ftrace_event_call *call;
137 mutex_lock(&event_mutex);
138 list_for_each_entry(call, &ftrace_events, list) {
139 ftrace_event_enable_disable(call, 0);
141 mutex_unlock(&event_mutex);
145 * __ftrace_set_clr_event(NULL, NULL, NULL, set) will set/unset all events.
147 static int __ftrace_set_clr_event(const char *match, const char *sub,
148 const char *event, int set)
150 struct ftrace_event_call *call;
153 mutex_lock(&event_mutex);
154 list_for_each_entry(call, &ftrace_events, list) {
156 if (!call->name || !call->regfunc)
160 strcmp(match, call->name) != 0 &&
161 strcmp(match, call->system) != 0)
164 if (sub && strcmp(sub, call->system) != 0)
167 if (event && strcmp(event, call->name) != 0)
170 ftrace_event_enable_disable(call, set);
174 mutex_unlock(&event_mutex);
179 static int ftrace_set_clr_event(char *buf, int set)
181 char *event = NULL, *sub = NULL, *match;
184 * The buf format can be <subsystem>:<event-name>
185 * *:<event-name> means any event by that name.
186 * :<event-name> is the same.
188 * <subsystem>:* means all events in that subsystem
189 * <subsystem>: means the same.
191 * <name> (no ':') means all events in a subsystem with
192 * the name <name> or any event that matches <name>
195 match = strsep(&buf, ":");
201 if (!strlen(sub) || strcmp(sub, "*") == 0)
203 if (!strlen(event) || strcmp(event, "*") == 0)
207 return __ftrace_set_clr_event(match, sub, event, set);
211 * trace_set_clr_event - enable or disable an event
212 * @system: system name to match (NULL for any system)
213 * @event: event name to match (NULL for all events, within system)
214 * @set: 1 to enable, 0 to disable
216 * This is a way for other parts of the kernel to enable or disable
219 * Returns 0 on success, -EINVAL if the parameters do not match any
222 int trace_set_clr_event(const char *system, const char *event, int set)
224 return __ftrace_set_clr_event(NULL, system, event, set);
227 /* 128 should be much more than enough */
228 #define EVENT_BUF_SIZE 127
231 ftrace_event_write(struct file *file, const char __user *ubuf,
232 size_t cnt, loff_t *ppos)
234 struct trace_parser parser;
240 ret = tracing_update_buffers();
244 if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1))
247 read = trace_get_user(&parser, ubuf, cnt, ppos);
249 if (read >= 0 && trace_parser_loaded((&parser))) {
252 if (*parser.buffer == '!')
255 parser.buffer[parser.idx] = 0;
257 ret = ftrace_set_clr_event(parser.buffer + !set, set);
265 trace_parser_put(&parser);
271 t_next(struct seq_file *m, void *v, loff_t *pos)
273 struct ftrace_event_call *call = v;
277 list_for_each_entry_continue(call, &ftrace_events, list) {
279 * The ftrace subsystem is for showing formats only.
280 * They can not be enabled or disabled via the event files.
289 static void *t_start(struct seq_file *m, loff_t *pos)
291 struct ftrace_event_call *call;
294 mutex_lock(&event_mutex);
296 call = list_entry(&ftrace_events, struct ftrace_event_call, list);
297 for (l = 0; l <= *pos; ) {
298 call = t_next(m, call, &l);
306 s_next(struct seq_file *m, void *v, loff_t *pos)
308 struct ftrace_event_call *call = v;
312 list_for_each_entry_continue(call, &ftrace_events, list) {
320 static void *s_start(struct seq_file *m, loff_t *pos)
322 struct ftrace_event_call *call;
325 mutex_lock(&event_mutex);
327 call = list_entry(&ftrace_events, struct ftrace_event_call, list);
328 for (l = 0; l <= *pos; ) {
329 call = s_next(m, call, &l);
336 static int t_show(struct seq_file *m, void *v)
338 struct ftrace_event_call *call = v;
340 if (strcmp(call->system, TRACE_SYSTEM) != 0)
341 seq_printf(m, "%s:", call->system);
342 seq_printf(m, "%s\n", call->name);
347 static void t_stop(struct seq_file *m, void *p)
349 mutex_unlock(&event_mutex);
353 ftrace_event_seq_open(struct inode *inode, struct file *file)
355 const struct seq_operations *seq_ops;
357 if ((file->f_mode & FMODE_WRITE) &&
358 (file->f_flags & O_TRUNC))
359 ftrace_clear_events();
361 seq_ops = inode->i_private;
362 return seq_open(file, seq_ops);
366 event_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
369 struct ftrace_event_call *call = filp->private_data;
377 return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2);
381 event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
384 struct ftrace_event_call *call = filp->private_data;
389 if (cnt >= sizeof(buf))
392 if (copy_from_user(&buf, ubuf, cnt))
397 ret = strict_strtoul(buf, 10, &val);
401 ret = tracing_update_buffers();
408 mutex_lock(&event_mutex);
409 ftrace_event_enable_disable(call, val);
410 mutex_unlock(&event_mutex);
423 system_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
426 const char set_to_char[4] = { '?', '0', '1', 'X' };
427 const char *system = filp->private_data;
428 struct ftrace_event_call *call;
433 mutex_lock(&event_mutex);
434 list_for_each_entry(call, &ftrace_events, list) {
435 if (!call->name || !call->regfunc)
438 if (system && strcmp(call->system, system) != 0)
442 * We need to find out if all the events are set
443 * or if all events or cleared, or if we have
446 set |= (1 << !!call->enabled);
449 * If we have a mixture, no need to look further.
454 mutex_unlock(&event_mutex);
456 buf[0] = set_to_char[set];
459 ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, 2);
465 system_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
468 const char *system = filp->private_data;
473 if (cnt >= sizeof(buf))
476 if (copy_from_user(&buf, ubuf, cnt))
481 ret = strict_strtoul(buf, 10, &val);
485 ret = tracing_update_buffers();
489 if (val != 0 && val != 1)
492 ret = __ftrace_set_clr_event(NULL, system, NULL, val);
504 extern char *__bad_type_size(void);
507 #define FIELD(type, name) \
508 sizeof(type) != sizeof(field.name) ? __bad_type_size() : \
509 #type, "common_" #name, offsetof(typeof(field), name), \
512 static int trace_write_header(struct trace_seq *s)
514 struct trace_entry field;
516 /* struct trace_entry */
517 return trace_seq_printf(s,
518 "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
519 "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
520 "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
521 "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
522 "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
524 FIELD(unsigned short, type),
525 FIELD(unsigned char, flags),
526 FIELD(unsigned char, preempt_count),
528 FIELD(int, lock_depth));
532 event_format_read(struct file *filp, char __user *ubuf, size_t cnt,
535 struct ftrace_event_call *call = filp->private_data;
543 s = kmalloc(sizeof(*s), GFP_KERNEL);
549 /* If any of the first writes fail, so will the show_format. */
551 trace_seq_printf(s, "name: %s\n", call->name);
552 trace_seq_printf(s, "ID: %d\n", call->id);
553 trace_seq_printf(s, "format:\n");
554 trace_write_header(s);
556 r = call->show_format(call, s);
559 * ug! The format output is bigger than a PAGE!!
561 buf = "FORMAT TOO BIG\n";
562 r = simple_read_from_buffer(ubuf, cnt, ppos,
567 r = simple_read_from_buffer(ubuf, cnt, ppos,
575 event_id_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
577 struct ftrace_event_call *call = filp->private_data;
584 s = kmalloc(sizeof(*s), GFP_KERNEL);
589 trace_seq_printf(s, "%d\n", call->id);
591 r = simple_read_from_buffer(ubuf, cnt, ppos,
598 event_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
601 struct ftrace_event_call *call = filp->private_data;
608 s = kmalloc(sizeof(*s), GFP_KERNEL);
614 print_event_filter(call, s);
615 r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
623 event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
626 struct ftrace_event_call *call = filp->private_data;
630 if (cnt >= PAGE_SIZE)
633 buf = (char *)__get_free_page(GFP_TEMPORARY);
637 if (copy_from_user(buf, ubuf, cnt)) {
638 free_page((unsigned long) buf);
643 err = apply_event_filter(call, buf);
644 free_page((unsigned long) buf);
654 subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
657 struct event_subsystem *system = filp->private_data;
664 s = kmalloc(sizeof(*s), GFP_KERNEL);
670 print_subsystem_event_filter(system, s);
671 r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
679 subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
682 struct event_subsystem *system = filp->private_data;
686 if (cnt >= PAGE_SIZE)
689 buf = (char *)__get_free_page(GFP_TEMPORARY);
693 if (copy_from_user(buf, ubuf, cnt)) {
694 free_page((unsigned long) buf);
699 err = apply_subsystem_event_filter(system, buf);
700 free_page((unsigned long) buf);
710 show_header(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
712 int (*func)(struct trace_seq *s) = filp->private_data;
719 s = kmalloc(sizeof(*s), GFP_KERNEL);
726 r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
733 static const struct seq_operations show_event_seq_ops = {
740 static const struct seq_operations show_set_event_seq_ops = {
747 static const struct file_operations ftrace_avail_fops = {
748 .open = ftrace_event_seq_open,
751 .release = seq_release,
754 static const struct file_operations ftrace_set_event_fops = {
755 .open = ftrace_event_seq_open,
757 .write = ftrace_event_write,
759 .release = seq_release,
762 static const struct file_operations ftrace_enable_fops = {
763 .open = tracing_open_generic,
764 .read = event_enable_read,
765 .write = event_enable_write,
768 static const struct file_operations ftrace_event_format_fops = {
769 .open = tracing_open_generic,
770 .read = event_format_read,
773 static const struct file_operations ftrace_event_id_fops = {
774 .open = tracing_open_generic,
775 .read = event_id_read,
778 static const struct file_operations ftrace_event_filter_fops = {
779 .open = tracing_open_generic,
780 .read = event_filter_read,
781 .write = event_filter_write,
784 static const struct file_operations ftrace_subsystem_filter_fops = {
785 .open = tracing_open_generic,
786 .read = subsystem_filter_read,
787 .write = subsystem_filter_write,
790 static const struct file_operations ftrace_system_enable_fops = {
791 .open = tracing_open_generic,
792 .read = system_enable_read,
793 .write = system_enable_write,
796 static const struct file_operations ftrace_show_header_fops = {
797 .open = tracing_open_generic,
801 static struct dentry *event_trace_events_dir(void)
803 static struct dentry *d_tracer;
804 static struct dentry *d_events;
809 d_tracer = tracing_init_dentry();
813 d_events = debugfs_create_dir("events", d_tracer);
815 pr_warning("Could not create debugfs "
816 "'events' directory\n");
821 static LIST_HEAD(event_subsystems);
823 static struct dentry *
824 event_subsystem_dir(const char *name, struct dentry *d_events)
826 struct event_subsystem *system;
827 struct dentry *entry;
829 /* First see if we did not already create this dir */
830 list_for_each_entry(system, &event_subsystems, list) {
831 if (strcmp(system->name, name) == 0) {
833 return system->entry;
837 /* need to create new entry */
838 system = kmalloc(sizeof(*system), GFP_KERNEL);
840 pr_warning("No memory to create event subsystem %s\n",
845 system->entry = debugfs_create_dir(name, d_events);
846 if (!system->entry) {
847 pr_warning("Could not create event subsystem %s\n",
853 system->nr_events = 1;
854 system->name = kstrdup(name, GFP_KERNEL);
856 debugfs_remove(system->entry);
861 list_add(&system->list, &event_subsystems);
863 system->filter = NULL;
865 system->filter = kzalloc(sizeof(struct event_filter), GFP_KERNEL);
866 if (!system->filter) {
867 pr_warning("Could not allocate filter for subsystem "
869 return system->entry;
872 entry = debugfs_create_file("filter", 0644, system->entry, system,
873 &ftrace_subsystem_filter_fops);
875 kfree(system->filter);
876 system->filter = NULL;
877 pr_warning("Could not create debugfs "
878 "'%s/filter' entry\n", name);
881 trace_create_file("enable", 0644, system->entry,
882 (void *)system->name,
883 &ftrace_system_enable_fops);
885 return system->entry;
889 event_create_dir(struct ftrace_event_call *call, struct dentry *d_events,
890 const struct file_operations *id,
891 const struct file_operations *enable,
892 const struct file_operations *filter,
893 const struct file_operations *format)
898 * If the trace point header did not define TRACE_SYSTEM
899 * then the system would be called "TRACE_SYSTEM".
901 if (strcmp(call->system, TRACE_SYSTEM) != 0)
902 d_events = event_subsystem_dir(call->system, d_events);
904 call->dir = debugfs_create_dir(call->name, d_events);
906 pr_warning("Could not create debugfs "
907 "'%s' directory\n", call->name);
912 trace_create_file("enable", 0644, call->dir, call,
915 if (call->id && call->profile_enable)
916 trace_create_file("id", 0444, call->dir, call,
919 if (call->define_fields) {
920 ret = call->define_fields(call);
922 pr_warning("Could not initialize trace point"
923 " events/%s\n", call->name);
926 trace_create_file("filter", 0644, call->dir, call,
930 /* A trace may not want to export its format */
931 if (!call->show_format)
934 trace_create_file("format", 0444, call->dir, call,
940 #define for_each_event(event, start, end) \
941 for (event = start; \
942 (unsigned long)event < (unsigned long)end; \
945 #ifdef CONFIG_MODULES
947 static LIST_HEAD(ftrace_module_file_list);
950 * Modules must own their file_operations to keep up with
951 * reference counting.
953 struct ftrace_module_file_ops {
954 struct list_head list;
956 struct file_operations id;
957 struct file_operations enable;
958 struct file_operations format;
959 struct file_operations filter;
962 static void remove_subsystem_dir(const char *name)
964 struct event_subsystem *system;
966 if (strcmp(name, TRACE_SYSTEM) == 0)
969 list_for_each_entry(system, &event_subsystems, list) {
970 if (strcmp(system->name, name) == 0) {
971 if (!--system->nr_events) {
972 struct event_filter *filter = system->filter;
974 debugfs_remove_recursive(system->entry);
975 list_del(&system->list);
977 kfree(filter->filter_string);
988 static struct ftrace_module_file_ops *
989 trace_create_file_ops(struct module *mod)
991 struct ftrace_module_file_ops *file_ops;
994 * This is a bit of a PITA. To allow for correct reference
995 * counting, modules must "own" their file_operations.
996 * To do this, we allocate the file operations that will be
997 * used in the event directory.
1000 file_ops = kmalloc(sizeof(*file_ops), GFP_KERNEL);
1004 file_ops->mod = mod;
1006 file_ops->id = ftrace_event_id_fops;
1007 file_ops->id.owner = mod;
1009 file_ops->enable = ftrace_enable_fops;
1010 file_ops->enable.owner = mod;
1012 file_ops->filter = ftrace_event_filter_fops;
1013 file_ops->filter.owner = mod;
1015 file_ops->format = ftrace_event_format_fops;
1016 file_ops->format.owner = mod;
1018 list_add(&file_ops->list, &ftrace_module_file_list);
1023 static void trace_module_add_events(struct module *mod)
1025 struct ftrace_module_file_ops *file_ops = NULL;
1026 struct ftrace_event_call *call, *start, *end;
1027 struct dentry *d_events;
1030 start = mod->trace_events;
1031 end = mod->trace_events + mod->num_trace_events;
1036 d_events = event_trace_events_dir();
1040 for_each_event(call, start, end) {
1041 /* The linker may leave blanks */
1044 if (call->raw_init) {
1045 ret = call->raw_init();
1048 pr_warning("Could not initialize trace "
1049 "point events/%s\n", call->name);
1054 * This module has events, create file ops for this module
1055 * if not already done.
1058 file_ops = trace_create_file_ops(mod);
1063 list_add(&call->list, &ftrace_events);
1064 event_create_dir(call, d_events,
1065 &file_ops->id, &file_ops->enable,
1066 &file_ops->filter, &file_ops->format);
1070 static void trace_module_remove_events(struct module *mod)
1072 struct ftrace_module_file_ops *file_ops;
1073 struct ftrace_event_call *call, *p;
1076 down_write(&trace_event_mutex);
1077 list_for_each_entry_safe(call, p, &ftrace_events, list) {
1078 if (call->mod == mod) {
1080 ftrace_event_enable_disable(call, 0);
1082 __unregister_ftrace_event(call->event);
1083 debugfs_remove_recursive(call->dir);
1084 list_del(&call->list);
1085 trace_destroy_fields(call);
1086 destroy_preds(call);
1087 remove_subsystem_dir(call->system);
1091 /* Now free the file_operations */
1092 list_for_each_entry(file_ops, &ftrace_module_file_list, list) {
1093 if (file_ops->mod == mod)
1096 if (&file_ops->list != &ftrace_module_file_list) {
1097 list_del(&file_ops->list);
1102 * It is safest to reset the ring buffer if the module being unloaded
1103 * registered any events.
1106 tracing_reset_current_online_cpus();
1107 up_write(&trace_event_mutex);
1110 static int trace_module_notify(struct notifier_block *self,
1111 unsigned long val, void *data)
1113 struct module *mod = data;
1115 mutex_lock(&event_mutex);
1117 case MODULE_STATE_COMING:
1118 trace_module_add_events(mod);
1120 case MODULE_STATE_GOING:
1121 trace_module_remove_events(mod);
1124 mutex_unlock(&event_mutex);
1129 static int trace_module_notify(struct notifier_block *self,
1130 unsigned long val, void *data)
1134 #endif /* CONFIG_MODULES */
1136 static struct notifier_block trace_module_nb = {
1137 .notifier_call = trace_module_notify,
1141 extern struct ftrace_event_call __start_ftrace_events[];
1142 extern struct ftrace_event_call __stop_ftrace_events[];
1144 static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata;
1146 static __init int setup_trace_event(char *str)
1148 strlcpy(bootup_event_buf, str, COMMAND_LINE_SIZE);
1149 ring_buffer_expanded = 1;
1150 tracing_selftest_disabled = 1;
1154 __setup("trace_event=", setup_trace_event);
1156 static __init int event_trace_init(void)
1158 struct ftrace_event_call *call;
1159 struct dentry *d_tracer;
1160 struct dentry *entry;
1161 struct dentry *d_events;
1163 char *buf = bootup_event_buf;
1166 d_tracer = tracing_init_dentry();
1170 entry = debugfs_create_file("available_events", 0444, d_tracer,
1171 (void *)&show_event_seq_ops,
1172 &ftrace_avail_fops);
1174 pr_warning("Could not create debugfs "
1175 "'available_events' entry\n");
1177 entry = debugfs_create_file("set_event", 0644, d_tracer,
1178 (void *)&show_set_event_seq_ops,
1179 &ftrace_set_event_fops);
1181 pr_warning("Could not create debugfs "
1182 "'set_event' entry\n");
1184 d_events = event_trace_events_dir();
1188 /* ring buffer internal formats */
1189 trace_create_file("header_page", 0444, d_events,
1190 ring_buffer_print_page_header,
1191 &ftrace_show_header_fops);
1193 trace_create_file("header_event", 0444, d_events,
1194 ring_buffer_print_entry_header,
1195 &ftrace_show_header_fops);
1197 trace_create_file("enable", 0644, d_events,
1198 NULL, &ftrace_system_enable_fops);
1200 for_each_event(call, __start_ftrace_events, __stop_ftrace_events) {
1201 /* The linker may leave blanks */
1204 if (call->raw_init) {
1205 ret = call->raw_init();
1208 pr_warning("Could not initialize trace "
1209 "point events/%s\n", call->name);
1213 list_add(&call->list, &ftrace_events);
1214 event_create_dir(call, d_events, &ftrace_event_id_fops,
1215 &ftrace_enable_fops, &ftrace_event_filter_fops,
1216 &ftrace_event_format_fops);
1220 token = strsep(&buf, ",");
1227 ret = ftrace_set_clr_event(token, 1);
1229 pr_warning("Failed to enable trace event: %s\n", token);
1232 ret = register_module_notifier(&trace_module_nb);
1234 pr_warning("Failed to register trace events module notifier\n");
1238 fs_initcall(event_trace_init);
1240 #ifdef CONFIG_FTRACE_STARTUP_TEST
1242 static DEFINE_SPINLOCK(test_spinlock);
1243 static DEFINE_SPINLOCK(test_spinlock_irq);
1244 static DEFINE_MUTEX(test_mutex);
1246 static __init void test_work(struct work_struct *dummy)
1248 spin_lock(&test_spinlock);
1249 spin_lock_irq(&test_spinlock_irq);
1251 spin_unlock_irq(&test_spinlock_irq);
1252 spin_unlock(&test_spinlock);
1254 mutex_lock(&test_mutex);
1256 mutex_unlock(&test_mutex);
1259 static __init int event_test_thread(void *unused)
1263 test_malloc = kmalloc(1234, GFP_KERNEL);
1265 pr_info("failed to kmalloc\n");
1267 schedule_on_each_cpu(test_work);
1271 set_current_state(TASK_INTERRUPTIBLE);
1272 while (!kthread_should_stop())
1279 * Do various things that may trigger events.
1281 static __init void event_test_stuff(void)
1283 struct task_struct *test_thread;
1285 test_thread = kthread_run(event_test_thread, NULL, "test-events");
1287 kthread_stop(test_thread);
1291 * For every trace event defined, we will test each trace point separately,
1292 * and then by groups, and finally all trace points.
1294 static __init void event_trace_self_tests(void)
1296 struct ftrace_event_call *call;
1297 struct event_subsystem *system;
1300 pr_info("Running tests on trace events:\n");
1302 list_for_each_entry(call, &ftrace_events, list) {
1304 /* Only test those that have a regfunc */
1309 * Testing syscall events here is pretty useless, but
1310 * we still do it if configured. But this is time consuming.
1311 * What we really need is a user thread to perform the
1312 * syscalls as we test.
1314 #ifndef CONFIG_EVENT_TRACE_TEST_SYSCALLS
1316 strcmp(call->system, "syscalls") == 0)
1320 pr_info("Testing event %s: ", call->name);
1323 * If an event is already enabled, someone is using
1324 * it and the self test should not be on.
1326 if (call->enabled) {
1327 pr_warning("Enabled event during self test!\n");
1332 ftrace_event_enable_disable(call, 1);
1334 ftrace_event_enable_disable(call, 0);
1339 /* Now test at the sub system level */
1341 pr_info("Running tests on trace event systems:\n");
1343 list_for_each_entry(system, &event_subsystems, list) {
1345 /* the ftrace system is special, skip it */
1346 if (strcmp(system->name, "ftrace") == 0)
1349 pr_info("Testing event system %s: ", system->name);
1351 ret = __ftrace_set_clr_event(NULL, system->name, NULL, 1);
1352 if (WARN_ON_ONCE(ret)) {
1353 pr_warning("error enabling system %s\n",
1360 ret = __ftrace_set_clr_event(NULL, system->name, NULL, 0);
1361 if (WARN_ON_ONCE(ret))
1362 pr_warning("error disabling system %s\n",
1368 /* Test with all events enabled */
1370 pr_info("Running tests on all trace events:\n");
1371 pr_info("Testing all events: ");
1373 ret = __ftrace_set_clr_event(NULL, NULL, NULL, 1);
1374 if (WARN_ON_ONCE(ret)) {
1375 pr_warning("error enabling all events\n");
1382 ret = __ftrace_set_clr_event(NULL, NULL, NULL, 0);
1383 if (WARN_ON_ONCE(ret)) {
1384 pr_warning("error disabling all events\n");
1391 #ifdef CONFIG_FUNCTION_TRACER
1393 static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable);
1396 function_test_events_call(unsigned long ip, unsigned long parent_ip)
1398 struct ring_buffer_event *event;
1399 struct ring_buffer *buffer;
1400 struct ftrace_entry *entry;
1401 unsigned long flags;
1407 pc = preempt_count();
1408 resched = ftrace_preempt_disable();
1409 cpu = raw_smp_processor_id();
1410 disabled = atomic_inc_return(&per_cpu(ftrace_test_event_disable, cpu));
1415 local_save_flags(flags);
1417 event = trace_current_buffer_lock_reserve(&buffer,
1418 TRACE_FN, sizeof(*entry),
1422 entry = ring_buffer_event_data(event);
1424 entry->parent_ip = parent_ip;
1426 trace_nowake_buffer_unlock_commit(buffer, event, flags, pc);
1429 atomic_dec(&per_cpu(ftrace_test_event_disable, cpu));
1430 ftrace_preempt_enable(resched);
1433 static struct ftrace_ops trace_ops __initdata =
1435 .func = function_test_events_call,
1438 static __init void event_trace_self_test_with_function(void)
1440 register_ftrace_function(&trace_ops);
1441 pr_info("Running tests again, along with the function tracer\n");
1442 event_trace_self_tests();
1443 unregister_ftrace_function(&trace_ops);
1446 static __init void event_trace_self_test_with_function(void)
1451 static __init int event_trace_self_tests_init(void)
1453 if (!tracing_selftest_disabled) {
1454 event_trace_self_tests();
1455 event_trace_self_test_with_function();
1461 late_initcall(event_trace_self_tests_init);