blob: 7d854290bf817ef8c6b116b031830dc060ae5dc7 [file] [log] [blame]
Steven Rostedtb77e38a2009-02-24 10:21:36 -05001/*
2 * event tracer
3 *
4 * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
5 *
Steven Rostedt981d0812009-03-02 13:53:59 -05006 * - Added format output of fields of the trace point.
7 * This was based off of work by Tom Zanussi <tzanussi@gmail.com>.
8 *
Steven Rostedtb77e38a2009-02-24 10:21:36 -05009 */
10
Steven Rostedte6187002009-04-15 13:36:40 -040011#include <linux/workqueue.h>
12#include <linux/spinlock.h>
13#include <linux/kthread.h>
Steven Rostedtb77e38a2009-02-24 10:21:36 -050014#include <linux/debugfs.h>
15#include <linux/uaccess.h>
16#include <linux/module.h>
17#include <linux/ctype.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090018#include <linux/slab.h>
Steven Rostedte6187002009-04-15 13:36:40 -040019#include <linux/delay.h>
Steven Rostedtb77e38a2009-02-24 10:21:36 -050020
Li Zefan020e5f82009-07-01 10:47:05 +080021#include <asm/setup.h>
22
Steven Rostedt91729ef2009-03-02 15:03:01 -050023#include "trace_output.h"
Steven Rostedtb77e38a2009-02-24 10:21:36 -050024
Steven Rostedt4e5292e2009-09-12 19:26:21 -040025#undef TRACE_SYSTEM
Steven Rostedtb628b3e2009-02-27 23:32:58 -050026#define TRACE_SYSTEM "TRACE_SYSTEM"
27
Li Zefan20c89282009-05-06 10:33:45 +080028DEFINE_MUTEX(event_mutex);
Steven Rostedt11a241a2009-03-02 11:49:04 -050029
Steven Rostedt04295782010-11-12 22:32:11 -050030DEFINE_MUTEX(event_storage_mutex);
31EXPORT_SYMBOL_GPL(event_storage_mutex);
32
33char event_storage[EVENT_STORAGE_SIZE];
34EXPORT_SYMBOL_GPL(event_storage);
35
Steven Rostedta59fd602009-04-10 13:52:20 -040036LIST_HEAD(ftrace_events);
zhangwei(Jovi)b3a8c6f2013-03-11 15:13:42 +080037static LIST_HEAD(ftrace_common_fields);
Steven Rostedta59fd602009-04-10 13:52:20 -040038
Steven Rostedtd1a29142013-02-27 20:23:57 -050039#define GFP_TRACE (GFP_KERNEL | __GFP_ZERO)
40
41static struct kmem_cache *field_cachep;
42static struct kmem_cache *file_cachep;
43
Steven Rostedt6e94a782013-06-27 10:58:31 -040044#define SYSTEM_FL_FREE_NAME (1 << 31)
45
46static inline int system_refcount(struct event_subsystem *system)
47{
48 return system->ref_count & ~SYSTEM_FL_FREE_NAME;
49}
50
51static int system_refcount_inc(struct event_subsystem *system)
52{
53 return (system->ref_count++) & ~SYSTEM_FL_FREE_NAME;
54}
55
56static int system_refcount_dec(struct event_subsystem *system)
57{
58 return (--system->ref_count) & ~SYSTEM_FL_FREE_NAME;
59}
60
Steven Rostedtae63b312012-05-03 23:09:03 -040061/* Double loops, do not use break, only goto's work */
62#define do_for_each_event_file(tr, file) \
63 list_for_each_entry(tr, &ftrace_trace_arrays, list) { \
64 list_for_each_entry(file, &tr->events, list)
65
66#define do_for_each_event_file_safe(tr, file) \
67 list_for_each_entry(tr, &ftrace_trace_arrays, list) { \
68 struct ftrace_event_file *___n; \
69 list_for_each_entry_safe(file, ___n, &tr->events, list)
70
71#define while_for_each_event_file() \
72 }
73
zhangwei(Jovi)b3a8c6f2013-03-11 15:13:42 +080074static struct list_head *
Steven Rostedt2e33af02010-04-22 10:35:55 -040075trace_get_fields(struct ftrace_event_call *event_call)
76{
77 if (!event_call->class->get_fields)
78 return &event_call->class->fields;
79 return event_call->class->get_fields(event_call);
80}
81
zhangwei(Jovi)b3a8c6f2013-03-11 15:13:42 +080082static struct ftrace_event_field *
83__find_event_field(struct list_head *head, char *name)
84{
85 struct ftrace_event_field *field;
86
87 list_for_each_entry(field, head, link) {
88 if (!strcmp(field->name, name))
89 return field;
90 }
91
92 return NULL;
93}
94
95struct ftrace_event_field *
96trace_find_event_field(struct ftrace_event_call *call, char *name)
97{
98 struct ftrace_event_field *field;
99 struct list_head *head;
100
101 field = __find_event_field(&ftrace_common_fields, name);
102 if (field)
103 return field;
104
105 head = trace_get_fields(call);
106 return __find_event_field(head, name);
107}
108
Li Zefan8728fe52010-05-24 16:22:49 +0800109static int __trace_define_field(struct list_head *head, const char *type,
110 const char *name, int offset, int size,
111 int is_signed, int filter_type)
Tom Zanussicf027f62009-03-22 03:30:39 -0500112{
113 struct ftrace_event_field *field;
114
Steven Rostedtd1a29142013-02-27 20:23:57 -0500115 field = kmem_cache_alloc(field_cachep, GFP_TRACE);
Tom Zanussicf027f62009-03-22 03:30:39 -0500116 if (!field)
Namhyung Kimaaf6ac02013-06-07 15:07:48 +0900117 return -ENOMEM;
Ingo Molnarfe9f57f2009-03-22 18:41:59 +0100118
Steven Rostedt92edca02013-02-27 20:41:37 -0500119 field->name = name;
120 field->type = type;
Ingo Molnarfe9f57f2009-03-22 18:41:59 +0100121
Li Zefan43b51ea2009-08-07 10:33:22 +0800122 if (filter_type == FILTER_OTHER)
123 field->filter_type = filter_assign_type(type);
124 else
125 field->filter_type = filter_type;
126
Tom Zanussicf027f62009-03-22 03:30:39 -0500127 field->offset = offset;
128 field->size = size;
Tom Zanussia118e4d2009-04-28 03:04:53 -0500129 field->is_signed = is_signed;
Li Zefanaa38e9f2009-08-07 10:33:02 +0800130
Steven Rostedt2e33af02010-04-22 10:35:55 -0400131 list_add(&field->link, head);
Tom Zanussicf027f62009-03-22 03:30:39 -0500132
133 return 0;
Tom Zanussicf027f62009-03-22 03:30:39 -0500134}
Li Zefan8728fe52010-05-24 16:22:49 +0800135
136int trace_define_field(struct ftrace_event_call *call, const char *type,
137 const char *name, int offset, int size, int is_signed,
138 int filter_type)
139{
140 struct list_head *head;
141
142 if (WARN_ON(!call->class))
143 return 0;
144
145 head = trace_get_fields(call);
146 return __trace_define_field(head, type, name, offset, size,
147 is_signed, filter_type);
148}
Steven Rostedt17c873e2009-04-10 18:12:50 -0400149EXPORT_SYMBOL_GPL(trace_define_field);
Tom Zanussicf027f62009-03-22 03:30:39 -0500150
Li Zefane647d6b2009-08-19 15:54:32 +0800151#define __common_field(type, item) \
Li Zefan8728fe52010-05-24 16:22:49 +0800152 ret = __trace_define_field(&ftrace_common_fields, #type, \
153 "common_" #item, \
154 offsetof(typeof(ent), item), \
155 sizeof(ent.item), \
156 is_signed_type(type), FILTER_OTHER); \
Li Zefane647d6b2009-08-19 15:54:32 +0800157 if (ret) \
158 return ret;
159
Li Zefan8728fe52010-05-24 16:22:49 +0800160static int trace_define_common_fields(void)
Li Zefane647d6b2009-08-19 15:54:32 +0800161{
162 int ret;
163 struct trace_entry ent;
164
165 __common_field(unsigned short, type);
166 __common_field(unsigned char, flags);
167 __common_field(unsigned char, preempt_count);
168 __common_field(int, pid);
Li Zefane647d6b2009-08-19 15:54:32 +0800169
170 return ret;
171}
172
zhangwei(Jovi)ad7067c2013-03-11 15:13:46 +0800173static void trace_destroy_fields(struct ftrace_event_call *call)
Li Zefan2df75e42009-05-06 10:33:04 +0800174{
175 struct ftrace_event_field *field, *next;
Steven Rostedt2e33af02010-04-22 10:35:55 -0400176 struct list_head *head;
Li Zefan2df75e42009-05-06 10:33:04 +0800177
Steven Rostedt2e33af02010-04-22 10:35:55 -0400178 head = trace_get_fields(call);
179 list_for_each_entry_safe(field, next, head, link) {
Li Zefan2df75e42009-05-06 10:33:04 +0800180 list_del(&field->link);
Steven Rostedtd1a29142013-02-27 20:23:57 -0500181 kmem_cache_free(field_cachep, field);
Li Zefan2df75e42009-05-06 10:33:04 +0800182 }
183}
184
Li Zefan87d9b4e2009-12-08 11:14:20 +0800185int trace_event_raw_init(struct ftrace_event_call *call)
186{
187 int id;
188
Steven Rostedt80decc72010-04-23 10:00:22 -0400189 id = register_ftrace_event(&call->event);
Li Zefan87d9b4e2009-12-08 11:14:20 +0800190 if (!id)
191 return -ENODEV;
Li Zefan87d9b4e2009-12-08 11:14:20 +0800192
193 return 0;
194}
195EXPORT_SYMBOL_GPL(trace_event_raw_init);
196
Jiri Olsaceec0b62012-02-15 15:51:49 +0100197int ftrace_event_reg(struct ftrace_event_call *call,
198 enum trace_reg type, void *data)
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400199{
Steven Rostedtae63b312012-05-03 23:09:03 -0400200 struct ftrace_event_file *file = data;
201
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400202 switch (type) {
203 case TRACE_REG_REGISTER:
204 return tracepoint_probe_register(call->name,
205 call->class->probe,
Steven Rostedtae63b312012-05-03 23:09:03 -0400206 file);
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400207 case TRACE_REG_UNREGISTER:
208 tracepoint_probe_unregister(call->name,
209 call->class->probe,
Steven Rostedtae63b312012-05-03 23:09:03 -0400210 file);
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400211 return 0;
212
213#ifdef CONFIG_PERF_EVENTS
214 case TRACE_REG_PERF_REGISTER:
215 return tracepoint_probe_register(call->name,
216 call->class->perf_probe,
217 call);
218 case TRACE_REG_PERF_UNREGISTER:
219 tracepoint_probe_unregister(call->name,
220 call->class->perf_probe,
221 call);
222 return 0;
Jiri Olsaceec0b62012-02-15 15:51:49 +0100223 case TRACE_REG_PERF_OPEN:
224 case TRACE_REG_PERF_CLOSE:
Jiri Olsa489c75c2012-02-15 15:51:50 +0100225 case TRACE_REG_PERF_ADD:
226 case TRACE_REG_PERF_DEL:
Jiri Olsaceec0b62012-02-15 15:51:49 +0100227 return 0;
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400228#endif
229 }
230 return 0;
231}
232EXPORT_SYMBOL_GPL(ftrace_event_reg);
233
Li Zefane870e9a2010-07-02 11:07:32 +0800234void trace_event_enable_cmd_record(bool enable)
235{
Steven Rostedtae63b312012-05-03 23:09:03 -0400236 struct ftrace_event_file *file;
237 struct trace_array *tr;
Li Zefane870e9a2010-07-02 11:07:32 +0800238
239 mutex_lock(&event_mutex);
Steven Rostedtae63b312012-05-03 23:09:03 -0400240 do_for_each_event_file(tr, file) {
241
242 if (!(file->flags & FTRACE_EVENT_FL_ENABLED))
Li Zefane870e9a2010-07-02 11:07:32 +0800243 continue;
244
245 if (enable) {
246 tracing_start_cmdline_record();
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400247 set_bit(FTRACE_EVENT_FL_RECORDED_CMD_BIT, &file->flags);
Li Zefane870e9a2010-07-02 11:07:32 +0800248 } else {
249 tracing_stop_cmdline_record();
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400250 clear_bit(FTRACE_EVENT_FL_RECORDED_CMD_BIT, &file->flags);
Li Zefane870e9a2010-07-02 11:07:32 +0800251 }
Steven Rostedtae63b312012-05-03 23:09:03 -0400252 } while_for_each_event_file();
Li Zefane870e9a2010-07-02 11:07:32 +0800253 mutex_unlock(&event_mutex);
254}
255
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400256static int __ftrace_event_enable_disable(struct ftrace_event_file *file,
257 int enable, int soft_disable)
Steven Rostedtfd994982009-02-28 02:41:25 -0500258{
Steven Rostedtae63b312012-05-03 23:09:03 -0400259 struct ftrace_event_call *call = file->event_call;
Li Zefan3b8e4272009-12-08 11:14:52 +0800260 int ret = 0;
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400261 int disable;
Li Zefan3b8e4272009-12-08 11:14:52 +0800262
Steven Rostedtfd994982009-02-28 02:41:25 -0500263 switch (enable) {
264 case 0:
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400265 /*
Masami Hiramatsu1cf4c072013-05-09 14:44:29 +0900266 * When soft_disable is set and enable is cleared, the sm_ref
267 * reference counter is decremented. If it reaches 0, we want
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400268 * to clear the SOFT_DISABLED flag but leave the event in the
269 * state that it was. That is, if the event was enabled and
270 * SOFT_DISABLED isn't set, then do nothing. But if SOFT_DISABLED
271 * is set we do not want the event to be enabled before we
272 * clear the bit.
273 *
274 * When soft_disable is not set but the SOFT_MODE flag is,
275 * we do nothing. Do not disable the tracepoint, otherwise
276 * "soft enable"s (clearing the SOFT_DISABLED bit) wont work.
277 */
278 if (soft_disable) {
Masami Hiramatsu1cf4c072013-05-09 14:44:29 +0900279 if (atomic_dec_return(&file->sm_ref) > 0)
280 break;
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400281 disable = file->flags & FTRACE_EVENT_FL_SOFT_DISABLED;
282 clear_bit(FTRACE_EVENT_FL_SOFT_MODE_BIT, &file->flags);
283 } else
284 disable = !(file->flags & FTRACE_EVENT_FL_SOFT_MODE);
285
286 if (disable && (file->flags & FTRACE_EVENT_FL_ENABLED)) {
287 clear_bit(FTRACE_EVENT_FL_ENABLED_BIT, &file->flags);
Steven Rostedtae63b312012-05-03 23:09:03 -0400288 if (file->flags & FTRACE_EVENT_FL_RECORDED_CMD) {
Li Zefane870e9a2010-07-02 11:07:32 +0800289 tracing_stop_cmdline_record();
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400290 clear_bit(FTRACE_EVENT_FL_RECORDED_CMD_BIT, &file->flags);
Li Zefane870e9a2010-07-02 11:07:32 +0800291 }
Steven Rostedtae63b312012-05-03 23:09:03 -0400292 call->class->reg(call, TRACE_REG_UNREGISTER, file);
Steven Rostedtfd994982009-02-28 02:41:25 -0500293 }
Tom Zanussi3baa5e42013-06-29 00:08:07 -0500294 /* If in SOFT_MODE, just set the SOFT_DISABLE_BIT, else clear it */
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400295 if (file->flags & FTRACE_EVENT_FL_SOFT_MODE)
296 set_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags);
Tom Zanussi3baa5e42013-06-29 00:08:07 -0500297 else
298 clear_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags);
Steven Rostedtfd994982009-02-28 02:41:25 -0500299 break;
300 case 1:
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400301 /*
302 * When soft_disable is set and enable is set, we want to
303 * register the tracepoint for the event, but leave the event
304 * as is. That means, if the event was already enabled, we do
305 * nothing (but set SOFT_MODE). If the event is disabled, we
306 * set SOFT_DISABLED before enabling the event tracepoint, so
307 * it still seems to be disabled.
308 */
309 if (!soft_disable)
310 clear_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags);
Masami Hiramatsu1cf4c072013-05-09 14:44:29 +0900311 else {
312 if (atomic_inc_return(&file->sm_ref) > 1)
313 break;
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400314 set_bit(FTRACE_EVENT_FL_SOFT_MODE_BIT, &file->flags);
Masami Hiramatsu1cf4c072013-05-09 14:44:29 +0900315 }
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400316
Steven Rostedtae63b312012-05-03 23:09:03 -0400317 if (!(file->flags & FTRACE_EVENT_FL_ENABLED)) {
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400318
319 /* Keep the event disabled, when going to SOFT_MODE. */
320 if (soft_disable)
321 set_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags);
322
Li Zefane870e9a2010-07-02 11:07:32 +0800323 if (trace_flags & TRACE_ITER_RECORD_CMD) {
324 tracing_start_cmdline_record();
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400325 set_bit(FTRACE_EVENT_FL_RECORDED_CMD_BIT, &file->flags);
Li Zefane870e9a2010-07-02 11:07:32 +0800326 }
Steven Rostedtae63b312012-05-03 23:09:03 -0400327 ret = call->class->reg(call, TRACE_REG_REGISTER, file);
Li Zefan3b8e4272009-12-08 11:14:52 +0800328 if (ret) {
329 tracing_stop_cmdline_record();
330 pr_info("event trace: Could not enable event "
331 "%s\n", call->name);
332 break;
333 }
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400334 set_bit(FTRACE_EVENT_FL_ENABLED_BIT, &file->flags);
Steven Rostedt (Red Hat)575380d2013-03-04 23:05:12 -0500335
336 /* WAS_ENABLED gets set but never cleared. */
337 call->flags |= TRACE_EVENT_FL_WAS_ENABLED;
Steven Rostedtfd994982009-02-28 02:41:25 -0500338 }
Steven Rostedtfd994982009-02-28 02:41:25 -0500339 break;
340 }
Li Zefan3b8e4272009-12-08 11:14:52 +0800341
342 return ret;
Steven Rostedtfd994982009-02-28 02:41:25 -0500343}
344
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400345static int ftrace_event_enable_disable(struct ftrace_event_file *file,
346 int enable)
347{
348 return __ftrace_event_enable_disable(file, enable, 0);
349}
350
Steven Rostedtae63b312012-05-03 23:09:03 -0400351static void ftrace_clear_events(struct trace_array *tr)
Zhaolei0e907c92009-05-25 18:13:59 +0800352{
Steven Rostedtae63b312012-05-03 23:09:03 -0400353 struct ftrace_event_file *file;
Zhaolei0e907c92009-05-25 18:13:59 +0800354
355 mutex_lock(&event_mutex);
Steven Rostedtae63b312012-05-03 23:09:03 -0400356 list_for_each_entry(file, &tr->events, list) {
357 ftrace_event_enable_disable(file, 0);
Zhaolei0e907c92009-05-25 18:13:59 +0800358 }
359 mutex_unlock(&event_mutex);
360}
361
Steven Rostedte9dbfae2011-07-05 11:36:06 -0400362static void __put_system(struct event_subsystem *system)
363{
364 struct event_filter *filter = system->filter;
365
Steven Rostedt6e94a782013-06-27 10:58:31 -0400366 WARN_ON_ONCE(system_refcount(system) == 0);
367 if (system_refcount_dec(system))
Steven Rostedte9dbfae2011-07-05 11:36:06 -0400368 return;
369
Steven Rostedtae63b312012-05-03 23:09:03 -0400370 list_del(&system->list);
371
Steven Rostedte9dbfae2011-07-05 11:36:06 -0400372 if (filter) {
373 kfree(filter->filter_string);
374 kfree(filter);
375 }
Steven Rostedt6e94a782013-06-27 10:58:31 -0400376 if (system->ref_count & SYSTEM_FL_FREE_NAME)
377 kfree(system->name);
Steven Rostedte9dbfae2011-07-05 11:36:06 -0400378 kfree(system);
379}
380
381static void __get_system(struct event_subsystem *system)
382{
Steven Rostedt6e94a782013-06-27 10:58:31 -0400383 WARN_ON_ONCE(system_refcount(system) == 0);
384 system_refcount_inc(system);
Steven Rostedte9dbfae2011-07-05 11:36:06 -0400385}
386
Steven Rostedtae63b312012-05-03 23:09:03 -0400387static void __get_system_dir(struct ftrace_subsystem_dir *dir)
388{
389 WARN_ON_ONCE(dir->ref_count == 0);
390 dir->ref_count++;
391 __get_system(dir->subsystem);
392}
393
394static void __put_system_dir(struct ftrace_subsystem_dir *dir)
395{
396 WARN_ON_ONCE(dir->ref_count == 0);
397 /* If the subsystem is about to be freed, the dir must be too */
Steven Rostedt6e94a782013-06-27 10:58:31 -0400398 WARN_ON_ONCE(system_refcount(dir->subsystem) == 1 && dir->ref_count != 1);
Steven Rostedtae63b312012-05-03 23:09:03 -0400399
400 __put_system(dir->subsystem);
401 if (!--dir->ref_count)
402 kfree(dir);
403}
404
405static void put_system(struct ftrace_subsystem_dir *dir)
Steven Rostedte9dbfae2011-07-05 11:36:06 -0400406{
407 mutex_lock(&event_mutex);
Steven Rostedtae63b312012-05-03 23:09:03 -0400408 __put_system_dir(dir);
Steven Rostedte9dbfae2011-07-05 11:36:06 -0400409 mutex_unlock(&event_mutex);
410}
411
Li Zefan8f31bfe2009-05-08 10:31:42 +0800412/*
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -0400413 * Open and update trace_array ref count.
414 * Must have the current trace_array passed to it.
415 */
416static int tracing_open_generic_file(struct inode *inode, struct file *filp)
417{
418 struct ftrace_event_file *file = inode->i_private;
419 struct trace_array *tr = file->tr;
420 int ret;
421
422 if (trace_array_get(tr) < 0)
423 return -ENODEV;
424
425 ret = tracing_open_generic(inode, filp);
426 if (ret < 0)
427 trace_array_put(tr);
428 return ret;
429}
430
431static int tracing_release_generic_file(struct inode *inode, struct file *filp)
432{
433 struct ftrace_event_file *file = inode->i_private;
434 struct trace_array *tr = file->tr;
435
436 trace_array_put(tr);
437
438 return 0;
439}
440
441/*
Li Zefan8f31bfe2009-05-08 10:31:42 +0800442 * __ftrace_set_clr_event(NULL, NULL, NULL, set) will set/unset all events.
443 */
Steven Rostedt (Red Hat)2a6c24a2013-07-02 14:48:23 -0400444static int
445__ftrace_set_clr_event_nolock(struct trace_array *tr, const char *match,
446 const char *sub, const char *event, int set)
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500447{
Steven Rostedtae63b312012-05-03 23:09:03 -0400448 struct ftrace_event_file *file;
Steven Rostedta59fd602009-04-10 13:52:20 -0400449 struct ftrace_event_call *call;
Steven Rostedt29f93942009-05-08 16:06:47 -0400450 int ret = -EINVAL;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500451
Steven Rostedtae63b312012-05-03 23:09:03 -0400452 list_for_each_entry(file, &tr->events, list) {
453
454 call = file->event_call;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500455
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400456 if (!call->name || !call->class || !call->class->reg)
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500457 continue;
Steven Rostedt1473e442009-02-24 14:15:08 -0500458
Steven Rostedt9b637762012-05-10 15:55:43 -0400459 if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
460 continue;
461
Steven Rostedtb628b3e2009-02-27 23:32:58 -0500462 if (match &&
463 strcmp(match, call->name) != 0 &&
Steven Rostedt8f082012010-04-20 10:47:33 -0400464 strcmp(match, call->class->system) != 0)
Steven Rostedtb628b3e2009-02-27 23:32:58 -0500465 continue;
466
Steven Rostedt8f082012010-04-20 10:47:33 -0400467 if (sub && strcmp(sub, call->class->system) != 0)
Steven Rostedtb628b3e2009-02-27 23:32:58 -0500468 continue;
469
470 if (event && strcmp(event, call->name) != 0)
Steven Rostedt1473e442009-02-24 14:15:08 -0500471 continue;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500472
Steven Rostedtae63b312012-05-03 23:09:03 -0400473 ftrace_event_enable_disable(file, set);
Steven Rostedtfd994982009-02-28 02:41:25 -0500474
Steven Rostedtb628b3e2009-02-27 23:32:58 -0500475 ret = 0;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500476 }
Steven Rostedt (Red Hat)2a6c24a2013-07-02 14:48:23 -0400477
478 return ret;
479}
480
481static int __ftrace_set_clr_event(struct trace_array *tr, const char *match,
482 const char *sub, const char *event, int set)
483{
484 int ret;
485
486 mutex_lock(&event_mutex);
487 ret = __ftrace_set_clr_event_nolock(tr, match, sub, event, set);
Steven Rostedt11a241a2009-03-02 11:49:04 -0500488 mutex_unlock(&event_mutex);
489
Steven Rostedtb628b3e2009-02-27 23:32:58 -0500490 return ret;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500491}
492
Steven Rostedtae63b312012-05-03 23:09:03 -0400493static int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set)
Li Zefan8f31bfe2009-05-08 10:31:42 +0800494{
495 char *event = NULL, *sub = NULL, *match;
496
497 /*
498 * The buf format can be <subsystem>:<event-name>
499 * *:<event-name> means any event by that name.
500 * :<event-name> is the same.
501 *
502 * <subsystem>:* means all events in that subsystem
503 * <subsystem>: means the same.
504 *
505 * <name> (no ':') means all events in a subsystem with
506 * the name <name> or any event that matches <name>
507 */
508
509 match = strsep(&buf, ":");
510 if (buf) {
511 sub = match;
512 event = buf;
513 match = NULL;
514
515 if (!strlen(sub) || strcmp(sub, "*") == 0)
516 sub = NULL;
517 if (!strlen(event) || strcmp(event, "*") == 0)
518 event = NULL;
519 }
520
Steven Rostedtae63b312012-05-03 23:09:03 -0400521 return __ftrace_set_clr_event(tr, match, sub, event, set);
Li Zefan8f31bfe2009-05-08 10:31:42 +0800522}
523
Steven Rostedt4671c792009-05-08 16:27:41 -0400524/**
525 * trace_set_clr_event - enable or disable an event
526 * @system: system name to match (NULL for any system)
527 * @event: event name to match (NULL for all events, within system)
528 * @set: 1 to enable, 0 to disable
529 *
530 * This is a way for other parts of the kernel to enable or disable
531 * event recording.
532 *
533 * Returns 0 on success, -EINVAL if the parameters do not match any
534 * registered events.
535 */
536int trace_set_clr_event(const char *system, const char *event, int set)
537{
Steven Rostedtae63b312012-05-03 23:09:03 -0400538 struct trace_array *tr = top_trace_array();
539
540 return __ftrace_set_clr_event(tr, NULL, system, event, set);
Steven Rostedt4671c792009-05-08 16:27:41 -0400541}
Yuanhan Liu56355b82010-11-08 14:05:12 +0800542EXPORT_SYMBOL_GPL(trace_set_clr_event);
Steven Rostedt4671c792009-05-08 16:27:41 -0400543
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500544/* 128 should be much more than enough */
545#define EVENT_BUF_SIZE 127
546
547static ssize_t
548ftrace_event_write(struct file *file, const char __user *ubuf,
549 size_t cnt, loff_t *ppos)
550{
jolsa@redhat.com48966362009-09-11 17:29:28 +0200551 struct trace_parser parser;
Steven Rostedtae63b312012-05-03 23:09:03 -0400552 struct seq_file *m = file->private_data;
553 struct trace_array *tr = m->private;
Li Zefan4ba79782009-09-22 13:52:20 +0800554 ssize_t read, ret;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500555
Li Zefan4ba79782009-09-22 13:52:20 +0800556 if (!cnt)
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500557 return 0;
558
Steven Rostedt1852fcc2009-03-11 14:33:00 -0400559 ret = tracing_update_buffers();
560 if (ret < 0)
561 return ret;
562
jolsa@redhat.com48966362009-09-11 17:29:28 +0200563 if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1))
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500564 return -ENOMEM;
565
jolsa@redhat.com48966362009-09-11 17:29:28 +0200566 read = trace_get_user(&parser, ubuf, cnt, ppos);
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500567
Li Zefan4ba79782009-09-22 13:52:20 +0800568 if (read >= 0 && trace_parser_loaded((&parser))) {
jolsa@redhat.com48966362009-09-11 17:29:28 +0200569 int set = 1;
570
571 if (*parser.buffer == '!')
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500572 set = 0;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500573
jolsa@redhat.com48966362009-09-11 17:29:28 +0200574 parser.buffer[parser.idx] = 0;
575
Steven Rostedtae63b312012-05-03 23:09:03 -0400576 ret = ftrace_set_clr_event(tr, parser.buffer + !set, set);
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500577 if (ret)
jolsa@redhat.com48966362009-09-11 17:29:28 +0200578 goto out_put;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500579 }
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500580
581 ret = read;
582
jolsa@redhat.com48966362009-09-11 17:29:28 +0200583 out_put:
584 trace_parser_put(&parser);
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500585
586 return ret;
587}
588
589static void *
590t_next(struct seq_file *m, void *v, loff_t *pos)
591{
Steven Rostedtae63b312012-05-03 23:09:03 -0400592 struct ftrace_event_file *file = v;
593 struct ftrace_event_call *call;
594 struct trace_array *tr = m->private;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500595
596 (*pos)++;
597
Steven Rostedtae63b312012-05-03 23:09:03 -0400598 list_for_each_entry_continue(file, &tr->events, list) {
599 call = file->event_call;
Steven Rostedt40e26812009-03-10 11:32:40 -0400600 /*
601 * The ftrace subsystem is for showing formats only.
602 * They can not be enabled or disabled via the event files.
603 */
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400604 if (call->class && call->class->reg)
Steven Rostedtae63b312012-05-03 23:09:03 -0400605 return file;
Steven Rostedt40e26812009-03-10 11:32:40 -0400606 }
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500607
Li Zefan30bd39c2009-09-18 14:07:05 +0800608 return NULL;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500609}
610
611static void *t_start(struct seq_file *m, loff_t *pos)
612{
Steven Rostedtae63b312012-05-03 23:09:03 -0400613 struct ftrace_event_file *file;
614 struct trace_array *tr = m->private;
Li Zefane1c7e2a2009-06-24 09:52:29 +0800615 loff_t l;
616
Li Zefan20c89282009-05-06 10:33:45 +0800617 mutex_lock(&event_mutex);
Li Zefane1c7e2a2009-06-24 09:52:29 +0800618
Steven Rostedtae63b312012-05-03 23:09:03 -0400619 file = list_entry(&tr->events, struct ftrace_event_file, list);
Li Zefane1c7e2a2009-06-24 09:52:29 +0800620 for (l = 0; l <= *pos; ) {
Steven Rostedtae63b312012-05-03 23:09:03 -0400621 file = t_next(m, file, &l);
622 if (!file)
Li Zefane1c7e2a2009-06-24 09:52:29 +0800623 break;
624 }
Steven Rostedtae63b312012-05-03 23:09:03 -0400625 return file;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500626}
627
628static void *
629s_next(struct seq_file *m, void *v, loff_t *pos)
630{
Steven Rostedtae63b312012-05-03 23:09:03 -0400631 struct ftrace_event_file *file = v;
632 struct trace_array *tr = m->private;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500633
634 (*pos)++;
635
Steven Rostedtae63b312012-05-03 23:09:03 -0400636 list_for_each_entry_continue(file, &tr->events, list) {
637 if (file->flags & FTRACE_EVENT_FL_ENABLED)
638 return file;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500639 }
640
Li Zefan30bd39c2009-09-18 14:07:05 +0800641 return NULL;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500642}
643
644static void *s_start(struct seq_file *m, loff_t *pos)
645{
Steven Rostedtae63b312012-05-03 23:09:03 -0400646 struct ftrace_event_file *file;
647 struct trace_array *tr = m->private;
Li Zefane1c7e2a2009-06-24 09:52:29 +0800648 loff_t l;
649
Li Zefan20c89282009-05-06 10:33:45 +0800650 mutex_lock(&event_mutex);
Li Zefane1c7e2a2009-06-24 09:52:29 +0800651
Steven Rostedtae63b312012-05-03 23:09:03 -0400652 file = list_entry(&tr->events, struct ftrace_event_file, list);
Li Zefane1c7e2a2009-06-24 09:52:29 +0800653 for (l = 0; l <= *pos; ) {
Steven Rostedtae63b312012-05-03 23:09:03 -0400654 file = s_next(m, file, &l);
655 if (!file)
Li Zefane1c7e2a2009-06-24 09:52:29 +0800656 break;
657 }
Steven Rostedtae63b312012-05-03 23:09:03 -0400658 return file;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500659}
660
661static int t_show(struct seq_file *m, void *v)
662{
Steven Rostedtae63b312012-05-03 23:09:03 -0400663 struct ftrace_event_file *file = v;
664 struct ftrace_event_call *call = file->event_call;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500665
Steven Rostedt8f082012010-04-20 10:47:33 -0400666 if (strcmp(call->class->system, TRACE_SYSTEM) != 0)
667 seq_printf(m, "%s:", call->class->system);
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500668 seq_printf(m, "%s\n", call->name);
669
670 return 0;
671}
672
673static void t_stop(struct seq_file *m, void *p)
674{
Li Zefan20c89282009-05-06 10:33:45 +0800675 mutex_unlock(&event_mutex);
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500676}
677
Steven Rostedt1473e442009-02-24 14:15:08 -0500678static ssize_t
679event_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
680 loff_t *ppos)
681{
Steven Rostedtae63b312012-05-03 23:09:03 -0400682 struct ftrace_event_file *file = filp->private_data;
Tom Zanussia4390592013-06-29 00:08:04 -0500683 char buf[4] = "0";
Steven Rostedt1473e442009-02-24 14:15:08 -0500684
Tom Zanussia4390592013-06-29 00:08:04 -0500685 if (file->flags & FTRACE_EVENT_FL_ENABLED &&
686 !(file->flags & FTRACE_EVENT_FL_SOFT_DISABLED))
687 strcpy(buf, "1");
688
689 if (file->flags & FTRACE_EVENT_FL_SOFT_DISABLED ||
690 file->flags & FTRACE_EVENT_FL_SOFT_MODE)
691 strcat(buf, "*");
692
693 strcat(buf, "\n");
Steven Rostedt1473e442009-02-24 14:15:08 -0500694
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400695 return simple_read_from_buffer(ubuf, cnt, ppos, buf, strlen(buf));
Steven Rostedt1473e442009-02-24 14:15:08 -0500696}
697
698static ssize_t
699event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
700 loff_t *ppos)
701{
Steven Rostedtae63b312012-05-03 23:09:03 -0400702 struct ftrace_event_file *file = filp->private_data;
Steven Rostedt1473e442009-02-24 14:15:08 -0500703 unsigned long val;
704 int ret;
705
Steven Rostedtae63b312012-05-03 23:09:03 -0400706 if (!file)
707 return -EINVAL;
708
Peter Huewe22fe9b52011-06-07 21:58:27 +0200709 ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
710 if (ret)
Steven Rostedt1473e442009-02-24 14:15:08 -0500711 return ret;
712
Steven Rostedt1852fcc2009-03-11 14:33:00 -0400713 ret = tracing_update_buffers();
714 if (ret < 0)
715 return ret;
716
Steven Rostedt1473e442009-02-24 14:15:08 -0500717 switch (val) {
718 case 0:
Steven Rostedt1473e442009-02-24 14:15:08 -0500719 case 1:
Steven Rostedt11a241a2009-03-02 11:49:04 -0500720 mutex_lock(&event_mutex);
Steven Rostedtae63b312012-05-03 23:09:03 -0400721 ret = ftrace_event_enable_disable(file, val);
Steven Rostedt11a241a2009-03-02 11:49:04 -0500722 mutex_unlock(&event_mutex);
Steven Rostedt1473e442009-02-24 14:15:08 -0500723 break;
724
725 default:
726 return -EINVAL;
727 }
728
729 *ppos += cnt;
730
Li Zefan3b8e4272009-12-08 11:14:52 +0800731 return ret ? ret : cnt;
Steven Rostedt1473e442009-02-24 14:15:08 -0500732}
733
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400734static ssize_t
735system_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
736 loff_t *ppos)
737{
Li Zefanc142b152009-05-08 10:32:05 +0800738 const char set_to_char[4] = { '?', '0', '1', 'X' };
Steven Rostedtae63b312012-05-03 23:09:03 -0400739 struct ftrace_subsystem_dir *dir = filp->private_data;
740 struct event_subsystem *system = dir->subsystem;
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400741 struct ftrace_event_call *call;
Steven Rostedtae63b312012-05-03 23:09:03 -0400742 struct ftrace_event_file *file;
743 struct trace_array *tr = dir->tr;
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400744 char buf[2];
Li Zefanc142b152009-05-08 10:32:05 +0800745 int set = 0;
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400746 int ret;
747
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400748 mutex_lock(&event_mutex);
Steven Rostedtae63b312012-05-03 23:09:03 -0400749 list_for_each_entry(file, &tr->events, list) {
750 call = file->event_call;
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400751 if (!call->name || !call->class || !call->class->reg)
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400752 continue;
753
Steven Rostedt40ee4df2011-07-05 14:32:51 -0400754 if (system && strcmp(call->class->system, system->name) != 0)
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400755 continue;
756
757 /*
758 * We need to find out if all the events are set
759 * or if all events or cleared, or if we have
760 * a mixture.
761 */
Steven Rostedtae63b312012-05-03 23:09:03 -0400762 set |= (1 << !!(file->flags & FTRACE_EVENT_FL_ENABLED));
Li Zefanc142b152009-05-08 10:32:05 +0800763
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400764 /*
765 * If we have a mixture, no need to look further.
766 */
Li Zefanc142b152009-05-08 10:32:05 +0800767 if (set == 3)
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400768 break;
769 }
770 mutex_unlock(&event_mutex);
771
Li Zefanc142b152009-05-08 10:32:05 +0800772 buf[0] = set_to_char[set];
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400773 buf[1] = '\n';
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400774
775 ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, 2);
776
777 return ret;
778}
779
780static ssize_t
781system_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
782 loff_t *ppos)
783{
Steven Rostedtae63b312012-05-03 23:09:03 -0400784 struct ftrace_subsystem_dir *dir = filp->private_data;
785 struct event_subsystem *system = dir->subsystem;
Steven Rostedt40ee4df2011-07-05 14:32:51 -0400786 const char *name = NULL;
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400787 unsigned long val;
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400788 ssize_t ret;
789
Peter Huewe22fe9b52011-06-07 21:58:27 +0200790 ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
791 if (ret)
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400792 return ret;
793
794 ret = tracing_update_buffers();
795 if (ret < 0)
796 return ret;
797
Li Zefan8f31bfe2009-05-08 10:31:42 +0800798 if (val != 0 && val != 1)
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400799 return -EINVAL;
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400800
Steven Rostedt40ee4df2011-07-05 14:32:51 -0400801 /*
802 * Opening of "enable" adds a ref count to system,
803 * so the name is safe to use.
804 */
805 if (system)
806 name = system->name;
807
Steven Rostedtae63b312012-05-03 23:09:03 -0400808 ret = __ftrace_set_clr_event(dir->tr, NULL, name, NULL, val);
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400809 if (ret)
Li Zefan8f31bfe2009-05-08 10:31:42 +0800810 goto out;
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400811
812 ret = cnt;
813
Li Zefan8f31bfe2009-05-08 10:31:42 +0800814out:
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400815 *ppos += cnt;
816
817 return ret;
818}
819
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400820enum {
821 FORMAT_HEADER = 1,
Li Zefan86397dc2010-08-17 13:53:06 +0800822 FORMAT_FIELD_SEPERATOR = 2,
823 FORMAT_PRINTFMT = 3,
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400824};
825
826static void *f_next(struct seq_file *m, void *v, loff_t *pos)
Steven Rostedt981d0812009-03-02 13:53:59 -0500827{
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400828 struct ftrace_event_call *call = m->private;
Lai Jiangshan5a65e952009-12-15 15:39:53 +0800829 struct ftrace_event_field *field;
Li Zefan86397dc2010-08-17 13:53:06 +0800830 struct list_head *common_head = &ftrace_common_fields;
831 struct list_head *head = trace_get_fields(call);
Steven Rostedt981d0812009-03-02 13:53:59 -0500832
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400833 (*pos)++;
Lai Jiangshan5a65e952009-12-15 15:39:53 +0800834
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400835 switch ((unsigned long)v) {
836 case FORMAT_HEADER:
Li Zefan86397dc2010-08-17 13:53:06 +0800837 if (unlikely(list_empty(common_head)))
838 return NULL;
Lai Jiangshan5a65e952009-12-15 15:39:53 +0800839
Li Zefan86397dc2010-08-17 13:53:06 +0800840 field = list_entry(common_head->prev,
841 struct ftrace_event_field, link);
842 return field;
843
844 case FORMAT_FIELD_SEPERATOR:
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400845 if (unlikely(list_empty(head)))
846 return NULL;
Lai Jiangshan5a65e952009-12-15 15:39:53 +0800847
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400848 field = list_entry(head->prev, struct ftrace_event_field, link);
849 return field;
Lai Jiangshan5a65e952009-12-15 15:39:53 +0800850
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400851 case FORMAT_PRINTFMT:
852 /* all done */
853 return NULL;
Lai Jiangshan5a65e952009-12-15 15:39:53 +0800854 }
855
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400856 field = v;
Li Zefan86397dc2010-08-17 13:53:06 +0800857 if (field->link.prev == common_head)
858 return (void *)FORMAT_FIELD_SEPERATOR;
859 else if (field->link.prev == head)
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400860 return (void *)FORMAT_PRINTFMT;
861
862 field = list_entry(field->link.prev, struct ftrace_event_field, link);
863
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400864 return field;
Li Zefan8728fe52010-05-24 16:22:49 +0800865}
Lai Jiangshan5a65e952009-12-15 15:39:53 +0800866
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400867static void *f_start(struct seq_file *m, loff_t *pos)
Li Zefan8728fe52010-05-24 16:22:49 +0800868{
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400869 loff_t l = 0;
870 void *p;
Li Zefan8728fe52010-05-24 16:22:49 +0800871
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400872 /* Start by showing the header */
873 if (!*pos)
874 return (void *)FORMAT_HEADER;
875
876 p = (void *)FORMAT_HEADER;
877 do {
878 p = f_next(m, p, &l);
879 } while (p && l < *pos);
880
881 return p;
882}
883
884static int f_show(struct seq_file *m, void *v)
885{
886 struct ftrace_event_call *call = m->private;
887 struct ftrace_event_field *field;
888 const char *array_descriptor;
889
890 switch ((unsigned long)v) {
891 case FORMAT_HEADER:
892 seq_printf(m, "name: %s\n", call->name);
893 seq_printf(m, "ID: %d\n", call->event.type);
894 seq_printf(m, "format:\n");
Li Zefan8728fe52010-05-24 16:22:49 +0800895 return 0;
896
Li Zefan86397dc2010-08-17 13:53:06 +0800897 case FORMAT_FIELD_SEPERATOR:
898 seq_putc(m, '\n');
899 return 0;
900
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400901 case FORMAT_PRINTFMT:
902 seq_printf(m, "\nprint fmt: %s\n",
903 call->print_fmt);
904 return 0;
Steven Rostedt981d0812009-03-02 13:53:59 -0500905 }
906
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400907 field = v;
908
909 /*
910 * Smartly shows the array type(except dynamic array).
911 * Normal:
912 * field:TYPE VAR
913 * If TYPE := TYPE[LEN], it is shown:
914 * field:TYPE VAR[LEN]
915 */
916 array_descriptor = strchr(field->type, '[');
917
918 if (!strncmp(field->type, "__data_loc", 10))
919 array_descriptor = NULL;
920
921 if (!array_descriptor)
922 seq_printf(m, "\tfield:%s %s;\toffset:%u;\tsize:%u;\tsigned:%d;\n",
923 field->type, field->name, field->offset,
924 field->size, !!field->is_signed);
925 else
926 seq_printf(m, "\tfield:%.*s %s%s;\toffset:%u;\tsize:%u;\tsigned:%d;\n",
927 (int)(array_descriptor - field->type),
928 field->type, field->name,
929 array_descriptor, field->offset,
930 field->size, !!field->is_signed);
931
932 return 0;
933}
934
935static void f_stop(struct seq_file *m, void *p)
936{
937}
938
939static const struct seq_operations trace_format_seq_ops = {
940 .start = f_start,
941 .next = f_next,
942 .stop = f_stop,
943 .show = f_show,
944};
945
946static int trace_format_open(struct inode *inode, struct file *file)
947{
948 struct ftrace_event_call *call = inode->i_private;
949 struct seq_file *m;
950 int ret;
951
952 ret = seq_open(file, &trace_format_seq_ops);
953 if (ret < 0)
954 return ret;
955
956 m = file->private_data;
957 m->private = call;
958
959 return 0;
Steven Rostedt981d0812009-03-02 13:53:59 -0500960}
961
Peter Zijlstra23725ae2009-03-19 20:26:13 +0100962static ssize_t
963event_id_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
964{
965 struct ftrace_event_call *call = filp->private_data;
966 struct trace_seq *s;
967 int r;
968
969 if (*ppos)
970 return 0;
971
972 s = kmalloc(sizeof(*s), GFP_KERNEL);
973 if (!s)
974 return -ENOMEM;
975
976 trace_seq_init(s);
Steven Rostedt32c0eda2010-04-23 10:38:03 -0400977 trace_seq_printf(s, "%d\n", call->event.type);
Peter Zijlstra23725ae2009-03-19 20:26:13 +0100978
979 r = simple_read_from_buffer(ubuf, cnt, ppos,
980 s->buffer, s->len);
981 kfree(s);
982 return r;
983}
984
Tom Zanussi7ce7e422009-03-22 03:31:04 -0500985static ssize_t
986event_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
987 loff_t *ppos)
988{
989 struct ftrace_event_call *call = filp->private_data;
990 struct trace_seq *s;
991 int r;
992
993 if (*ppos)
994 return 0;
995
996 s = kmalloc(sizeof(*s), GFP_KERNEL);
997 if (!s)
998 return -ENOMEM;
999
1000 trace_seq_init(s);
1001
Tom Zanussi8b372562009-04-28 03:04:59 -05001002 print_event_filter(call, s);
Tom Zanussi4bda2d52009-03-24 02:14:31 -05001003 r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001004
1005 kfree(s);
1006
1007 return r;
1008}
1009
1010static ssize_t
1011event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
1012 loff_t *ppos)
1013{
1014 struct ftrace_event_call *call = filp->private_data;
Tom Zanussi8b372562009-04-28 03:04:59 -05001015 char *buf;
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001016 int err;
1017
Tom Zanussi8b372562009-04-28 03:04:59 -05001018 if (cnt >= PAGE_SIZE)
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001019 return -EINVAL;
1020
Tom Zanussi8b372562009-04-28 03:04:59 -05001021 buf = (char *)__get_free_page(GFP_TEMPORARY);
1022 if (!buf)
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001023 return -ENOMEM;
1024
Tom Zanussi8b372562009-04-28 03:04:59 -05001025 if (copy_from_user(buf, ubuf, cnt)) {
1026 free_page((unsigned long) buf);
1027 return -EFAULT;
1028 }
1029 buf[cnt] = '\0';
1030
1031 err = apply_event_filter(call, buf);
1032 free_page((unsigned long) buf);
1033 if (err < 0)
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001034 return err;
Tom Zanussi0a19e532009-04-13 03:17:50 -05001035
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001036 *ppos += cnt;
1037
1038 return cnt;
1039}
1040
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001041static LIST_HEAD(event_subsystems);
1042
1043static int subsystem_open(struct inode *inode, struct file *filp)
1044{
1045 struct event_subsystem *system = NULL;
Steven Rostedtae63b312012-05-03 23:09:03 -04001046 struct ftrace_subsystem_dir *dir = NULL; /* Initialize for gcc */
1047 struct trace_array *tr;
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001048 int ret;
1049
1050 /* Make sure the system still exists */
Alexander Z Lama8227412013-07-01 19:37:54 -07001051 mutex_lock(&trace_types_lock);
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001052 mutex_lock(&event_mutex);
Steven Rostedtae63b312012-05-03 23:09:03 -04001053 list_for_each_entry(tr, &ftrace_trace_arrays, list) {
1054 list_for_each_entry(dir, &tr->systems, list) {
1055 if (dir == inode->i_private) {
1056 /* Don't open systems with no events */
1057 if (dir->nr_events) {
1058 __get_system_dir(dir);
1059 system = dir->subsystem;
1060 }
1061 goto exit_loop;
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001062 }
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001063 }
1064 }
Steven Rostedtae63b312012-05-03 23:09:03 -04001065 exit_loop:
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001066 mutex_unlock(&event_mutex);
Alexander Z Lama8227412013-07-01 19:37:54 -07001067 mutex_unlock(&trace_types_lock);
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001068
Steven Rostedtae63b312012-05-03 23:09:03 -04001069 if (!system)
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001070 return -ENODEV;
1071
Steven Rostedtae63b312012-05-03 23:09:03 -04001072 /* Some versions of gcc think dir can be uninitialized here */
1073 WARN_ON(!dir);
1074
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001075 /* Still need to increment the ref count of the system */
1076 if (trace_array_get(tr) < 0) {
Steven Rostedtae63b312012-05-03 23:09:03 -04001077 put_system(dir);
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001078 return -ENODEV;
1079 }
1080
1081 ret = tracing_open_generic(inode, filp);
1082 if (ret < 0) {
1083 trace_array_put(tr);
1084 put_system(dir);
1085 }
Steven Rostedtae63b312012-05-03 23:09:03 -04001086
1087 return ret;
1088}
1089
1090static int system_tr_open(struct inode *inode, struct file *filp)
1091{
1092 struct ftrace_subsystem_dir *dir;
1093 struct trace_array *tr = inode->i_private;
1094 int ret;
1095
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001096 if (trace_array_get(tr) < 0)
1097 return -ENODEV;
1098
Steven Rostedtae63b312012-05-03 23:09:03 -04001099 /* Make a temporary dir that has no system but points to tr */
1100 dir = kzalloc(sizeof(*dir), GFP_KERNEL);
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001101 if (!dir) {
1102 trace_array_put(tr);
Steven Rostedtae63b312012-05-03 23:09:03 -04001103 return -ENOMEM;
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001104 }
Steven Rostedtae63b312012-05-03 23:09:03 -04001105
1106 dir->tr = tr;
1107
1108 ret = tracing_open_generic(inode, filp);
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001109 if (ret < 0) {
1110 trace_array_put(tr);
Steven Rostedtae63b312012-05-03 23:09:03 -04001111 kfree(dir);
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001112 }
Steven Rostedtae63b312012-05-03 23:09:03 -04001113
1114 filp->private_data = dir;
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001115
1116 return ret;
1117}
1118
1119static int subsystem_release(struct inode *inode, struct file *file)
1120{
Steven Rostedtae63b312012-05-03 23:09:03 -04001121 struct ftrace_subsystem_dir *dir = file->private_data;
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001122
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001123 trace_array_put(dir->tr);
1124
Steven Rostedtae63b312012-05-03 23:09:03 -04001125 /*
1126 * If dir->subsystem is NULL, then this is a temporary
1127 * descriptor that was made for a trace_array to enable
1128 * all subsystems.
1129 */
1130 if (dir->subsystem)
1131 put_system(dir);
1132 else
1133 kfree(dir);
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001134
1135 return 0;
1136}
1137
Tom Zanussicfb180f2009-03-22 03:31:17 -05001138static ssize_t
1139subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
1140 loff_t *ppos)
1141{
Steven Rostedtae63b312012-05-03 23:09:03 -04001142 struct ftrace_subsystem_dir *dir = filp->private_data;
1143 struct event_subsystem *system = dir->subsystem;
Tom Zanussicfb180f2009-03-22 03:31:17 -05001144 struct trace_seq *s;
1145 int r;
1146
1147 if (*ppos)
1148 return 0;
1149
1150 s = kmalloc(sizeof(*s), GFP_KERNEL);
1151 if (!s)
1152 return -ENOMEM;
1153
1154 trace_seq_init(s);
1155
Tom Zanussi8b372562009-04-28 03:04:59 -05001156 print_subsystem_event_filter(system, s);
Tom Zanussi4bda2d52009-03-24 02:14:31 -05001157 r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
Tom Zanussicfb180f2009-03-22 03:31:17 -05001158
1159 kfree(s);
1160
1161 return r;
1162}
1163
1164static ssize_t
1165subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
1166 loff_t *ppos)
1167{
Steven Rostedtae63b312012-05-03 23:09:03 -04001168 struct ftrace_subsystem_dir *dir = filp->private_data;
Tom Zanussi8b372562009-04-28 03:04:59 -05001169 char *buf;
Tom Zanussicfb180f2009-03-22 03:31:17 -05001170 int err;
1171
Tom Zanussi8b372562009-04-28 03:04:59 -05001172 if (cnt >= PAGE_SIZE)
Tom Zanussicfb180f2009-03-22 03:31:17 -05001173 return -EINVAL;
1174
Tom Zanussi8b372562009-04-28 03:04:59 -05001175 buf = (char *)__get_free_page(GFP_TEMPORARY);
1176 if (!buf)
Tom Zanussicfb180f2009-03-22 03:31:17 -05001177 return -ENOMEM;
1178
Tom Zanussi8b372562009-04-28 03:04:59 -05001179 if (copy_from_user(buf, ubuf, cnt)) {
1180 free_page((unsigned long) buf);
1181 return -EFAULT;
Tom Zanussicfb180f2009-03-22 03:31:17 -05001182 }
Tom Zanussi8b372562009-04-28 03:04:59 -05001183 buf[cnt] = '\0';
Tom Zanussicfb180f2009-03-22 03:31:17 -05001184
Steven Rostedtae63b312012-05-03 23:09:03 -04001185 err = apply_subsystem_event_filter(dir, buf);
Tom Zanussi8b372562009-04-28 03:04:59 -05001186 free_page((unsigned long) buf);
1187 if (err < 0)
Li Zefan44e9c8b2009-04-11 15:55:28 +08001188 return err;
Tom Zanussicfb180f2009-03-22 03:31:17 -05001189
1190 *ppos += cnt;
1191
1192 return cnt;
1193}
1194
Steven Rostedtd1b182a2009-04-15 16:53:47 -04001195static ssize_t
1196show_header(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
1197{
1198 int (*func)(struct trace_seq *s) = filp->private_data;
1199 struct trace_seq *s;
1200 int r;
1201
1202 if (*ppos)
1203 return 0;
1204
1205 s = kmalloc(sizeof(*s), GFP_KERNEL);
1206 if (!s)
1207 return -ENOMEM;
1208
1209 trace_seq_init(s);
1210
1211 func(s);
1212 r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
1213
1214 kfree(s);
1215
1216 return r;
1217}
1218
Steven Rostedt15075ca2012-05-03 14:57:28 -04001219static int ftrace_event_avail_open(struct inode *inode, struct file *file);
1220static int ftrace_event_set_open(struct inode *inode, struct file *file);
1221
Steven Rostedtb77e38a2009-02-24 10:21:36 -05001222static const struct seq_operations show_event_seq_ops = {
1223 .start = t_start,
1224 .next = t_next,
1225 .show = t_show,
1226 .stop = t_stop,
1227};
1228
1229static const struct seq_operations show_set_event_seq_ops = {
1230 .start = s_start,
1231 .next = s_next,
1232 .show = t_show,
1233 .stop = t_stop,
1234};
1235
Steven Rostedt2314c4a2009-03-10 12:04:02 -04001236static const struct file_operations ftrace_avail_fops = {
Steven Rostedt15075ca2012-05-03 14:57:28 -04001237 .open = ftrace_event_avail_open,
Steven Rostedt2314c4a2009-03-10 12:04:02 -04001238 .read = seq_read,
1239 .llseek = seq_lseek,
1240 .release = seq_release,
1241};
1242
Steven Rostedtb77e38a2009-02-24 10:21:36 -05001243static const struct file_operations ftrace_set_event_fops = {
Steven Rostedt15075ca2012-05-03 14:57:28 -04001244 .open = ftrace_event_set_open,
Steven Rostedtb77e38a2009-02-24 10:21:36 -05001245 .read = seq_read,
1246 .write = ftrace_event_write,
1247 .llseek = seq_lseek,
1248 .release = seq_release,
1249};
1250
Steven Rostedt1473e442009-02-24 14:15:08 -05001251static const struct file_operations ftrace_enable_fops = {
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001252 .open = tracing_open_generic_file,
Steven Rostedt1473e442009-02-24 14:15:08 -05001253 .read = event_enable_read,
1254 .write = event_enable_write,
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001255 .release = tracing_release_generic_file,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001256 .llseek = default_llseek,
Steven Rostedt1473e442009-02-24 14:15:08 -05001257};
1258
Steven Rostedt981d0812009-03-02 13:53:59 -05001259static const struct file_operations ftrace_event_format_fops = {
Steven Rostedt2a37a3d2010-06-03 15:21:34 -04001260 .open = trace_format_open,
1261 .read = seq_read,
1262 .llseek = seq_lseek,
1263 .release = seq_release,
Steven Rostedt981d0812009-03-02 13:53:59 -05001264};
1265
Peter Zijlstra23725ae2009-03-19 20:26:13 +01001266static const struct file_operations ftrace_event_id_fops = {
1267 .open = tracing_open_generic,
1268 .read = event_id_read,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001269 .llseek = default_llseek,
Peter Zijlstra23725ae2009-03-19 20:26:13 +01001270};
1271
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001272static const struct file_operations ftrace_event_filter_fops = {
1273 .open = tracing_open_generic,
1274 .read = event_filter_read,
1275 .write = event_filter_write,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001276 .llseek = default_llseek,
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001277};
1278
Tom Zanussicfb180f2009-03-22 03:31:17 -05001279static const struct file_operations ftrace_subsystem_filter_fops = {
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001280 .open = subsystem_open,
Tom Zanussicfb180f2009-03-22 03:31:17 -05001281 .read = subsystem_filter_read,
1282 .write = subsystem_filter_write,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001283 .llseek = default_llseek,
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001284 .release = subsystem_release,
Tom Zanussicfb180f2009-03-22 03:31:17 -05001285};
1286
Steven Rostedt8ae79a12009-05-06 22:52:15 -04001287static const struct file_operations ftrace_system_enable_fops = {
Steven Rostedt40ee4df2011-07-05 14:32:51 -04001288 .open = subsystem_open,
Steven Rostedt8ae79a12009-05-06 22:52:15 -04001289 .read = system_enable_read,
1290 .write = system_enable_write,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001291 .llseek = default_llseek,
Steven Rostedt40ee4df2011-07-05 14:32:51 -04001292 .release = subsystem_release,
Steven Rostedt8ae79a12009-05-06 22:52:15 -04001293};
1294
Steven Rostedtae63b312012-05-03 23:09:03 -04001295static const struct file_operations ftrace_tr_enable_fops = {
1296 .open = system_tr_open,
1297 .read = system_enable_read,
1298 .write = system_enable_write,
1299 .llseek = default_llseek,
1300 .release = subsystem_release,
1301};
1302
Steven Rostedtd1b182a2009-04-15 16:53:47 -04001303static const struct file_operations ftrace_show_header_fops = {
1304 .open = tracing_open_generic,
1305 .read = show_header,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001306 .llseek = default_llseek,
Steven Rostedtd1b182a2009-04-15 16:53:47 -04001307};
1308
Steven Rostedtae63b312012-05-03 23:09:03 -04001309static int
1310ftrace_event_open(struct inode *inode, struct file *file,
1311 const struct seq_operations *seq_ops)
Steven Rostedt1473e442009-02-24 14:15:08 -05001312{
Steven Rostedtae63b312012-05-03 23:09:03 -04001313 struct seq_file *m;
1314 int ret;
Steven Rostedt1473e442009-02-24 14:15:08 -05001315
Steven Rostedtae63b312012-05-03 23:09:03 -04001316 ret = seq_open(file, seq_ops);
1317 if (ret < 0)
1318 return ret;
1319 m = file->private_data;
1320 /* copy tr over to seq ops */
1321 m->private = inode->i_private;
Steven Rostedt1473e442009-02-24 14:15:08 -05001322
Steven Rostedtae63b312012-05-03 23:09:03 -04001323 return ret;
Steven Rostedt1473e442009-02-24 14:15:08 -05001324}
1325
Steven Rostedt15075ca2012-05-03 14:57:28 -04001326static int
1327ftrace_event_avail_open(struct inode *inode, struct file *file)
1328{
1329 const struct seq_operations *seq_ops = &show_event_seq_ops;
1330
Steven Rostedtae63b312012-05-03 23:09:03 -04001331 return ftrace_event_open(inode, file, seq_ops);
Steven Rostedt15075ca2012-05-03 14:57:28 -04001332}
1333
1334static int
1335ftrace_event_set_open(struct inode *inode, struct file *file)
1336{
1337 const struct seq_operations *seq_ops = &show_set_event_seq_ops;
Steven Rostedtae63b312012-05-03 23:09:03 -04001338 struct trace_array *tr = inode->i_private;
Steven Rostedt15075ca2012-05-03 14:57:28 -04001339
1340 if ((file->f_mode & FMODE_WRITE) &&
1341 (file->f_flags & O_TRUNC))
Steven Rostedtae63b312012-05-03 23:09:03 -04001342 ftrace_clear_events(tr);
Steven Rostedt15075ca2012-05-03 14:57:28 -04001343
Steven Rostedtae63b312012-05-03 23:09:03 -04001344 return ftrace_event_open(inode, file, seq_ops);
Steven Rostedt15075ca2012-05-03 14:57:28 -04001345}
1346
Steven Rostedtae63b312012-05-03 23:09:03 -04001347static struct event_subsystem *
1348create_new_subsystem(const char *name)
Steven Rostedt6ecc2d12009-02-27 21:33:02 -05001349{
1350 struct event_subsystem *system;
Steven Rostedt6ecc2d12009-02-27 21:33:02 -05001351
1352 /* need to create new entry */
1353 system = kmalloc(sizeof(*system), GFP_KERNEL);
Steven Rostedtae63b312012-05-03 23:09:03 -04001354 if (!system)
1355 return NULL;
Steven Rostedt6ecc2d12009-02-27 21:33:02 -05001356
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001357 system->ref_count = 1;
Steven Rostedt6e94a782013-06-27 10:58:31 -04001358
1359 /* Only allocate if dynamic (kprobes and modules) */
1360 if (!core_kernel_data((unsigned long)name)) {
1361 system->ref_count |= SYSTEM_FL_FREE_NAME;
1362 system->name = kstrdup(name, GFP_KERNEL);
1363 if (!system->name)
1364 goto out_free;
1365 } else
1366 system->name = name;
Steven Rostedt6ecc2d12009-02-27 21:33:02 -05001367
Tom Zanussi30e673b2009-04-28 03:04:47 -05001368 system->filter = NULL;
Tom Zanussicfb180f2009-03-22 03:31:17 -05001369
Tom Zanussi8b372562009-04-28 03:04:59 -05001370 system->filter = kzalloc(sizeof(struct event_filter), GFP_KERNEL);
Steven Rostedtae63b312012-05-03 23:09:03 -04001371 if (!system->filter)
1372 goto out_free;
1373
1374 list_add(&system->list, &event_subsystems);
1375
1376 return system;
1377
1378 out_free:
Steven Rostedt6e94a782013-06-27 10:58:31 -04001379 if (system->ref_count & SYSTEM_FL_FREE_NAME)
1380 kfree(system->name);
Steven Rostedtae63b312012-05-03 23:09:03 -04001381 kfree(system);
1382 return NULL;
1383}
1384
1385static struct dentry *
1386event_subsystem_dir(struct trace_array *tr, const char *name,
1387 struct ftrace_event_file *file, struct dentry *parent)
1388{
1389 struct ftrace_subsystem_dir *dir;
1390 struct event_subsystem *system;
1391 struct dentry *entry;
1392
1393 /* First see if we did not already create this dir */
1394 list_for_each_entry(dir, &tr->systems, list) {
1395 system = dir->subsystem;
1396 if (strcmp(system->name, name) == 0) {
1397 dir->nr_events++;
1398 file->system = dir;
1399 return dir->entry;
1400 }
Tom Zanussi8b372562009-04-28 03:04:59 -05001401 }
1402
Steven Rostedtae63b312012-05-03 23:09:03 -04001403 /* Now see if the system itself exists. */
1404 list_for_each_entry(system, &event_subsystems, list) {
1405 if (strcmp(system->name, name) == 0)
1406 break;
1407 }
1408 /* Reset system variable when not found */
1409 if (&system->list == &event_subsystems)
1410 system = NULL;
1411
1412 dir = kmalloc(sizeof(*dir), GFP_KERNEL);
1413 if (!dir)
1414 goto out_fail;
1415
1416 if (!system) {
1417 system = create_new_subsystem(name);
1418 if (!system)
1419 goto out_free;
1420 } else
1421 __get_system(system);
1422
1423 dir->entry = debugfs_create_dir(name, parent);
1424 if (!dir->entry) {
1425 pr_warning("Failed to create system directory %s\n", name);
1426 __put_system(system);
1427 goto out_free;
1428 }
1429
1430 dir->tr = tr;
1431 dir->ref_count = 1;
1432 dir->nr_events = 1;
1433 dir->subsystem = system;
1434 file->system = dir;
1435
1436 entry = debugfs_create_file("filter", 0644, dir->entry, dir,
Tom Zanussie1112b42009-03-31 00:48:49 -05001437 &ftrace_subsystem_filter_fops);
Tom Zanussi8b372562009-04-28 03:04:59 -05001438 if (!entry) {
1439 kfree(system->filter);
1440 system->filter = NULL;
Steven Rostedtae63b312012-05-03 23:09:03 -04001441 pr_warning("Could not create debugfs '%s/filter' entry\n", name);
Tom Zanussi8b372562009-04-28 03:04:59 -05001442 }
Tom Zanussie1112b42009-03-31 00:48:49 -05001443
Steven Rostedtae63b312012-05-03 23:09:03 -04001444 trace_create_file("enable", 0644, dir->entry, dir,
Frederic Weisbeckerf3f3f002009-09-24 15:27:41 +02001445 &ftrace_system_enable_fops);
Steven Rostedt8ae79a12009-05-06 22:52:15 -04001446
Steven Rostedtae63b312012-05-03 23:09:03 -04001447 list_add(&dir->list, &tr->systems);
1448
1449 return dir->entry;
1450
1451 out_free:
1452 kfree(dir);
1453 out_fail:
1454 /* Only print this message if failed on memory allocation */
1455 if (!dir || !system)
1456 pr_warning("No memory to create event subsystem %s\n",
1457 name);
1458 return NULL;
Steven Rostedt6ecc2d12009-02-27 21:33:02 -05001459}
1460
Steven Rostedt1473e442009-02-24 14:15:08 -05001461static int
Steven Rostedtae63b312012-05-03 23:09:03 -04001462event_create_dir(struct dentry *parent,
1463 struct ftrace_event_file *file,
Steven Rostedt701970b2009-04-24 23:11:22 -04001464 const struct file_operations *id,
1465 const struct file_operations *enable,
1466 const struct file_operations *filter,
1467 const struct file_operations *format)
Steven Rostedt1473e442009-02-24 14:15:08 -05001468{
Steven Rostedtae63b312012-05-03 23:09:03 -04001469 struct ftrace_event_call *call = file->event_call;
1470 struct trace_array *tr = file->tr;
Steven Rostedt2e33af02010-04-22 10:35:55 -04001471 struct list_head *head;
Steven Rostedtae63b312012-05-03 23:09:03 -04001472 struct dentry *d_events;
Steven Rostedtfd994982009-02-28 02:41:25 -05001473 int ret;
Steven Rostedt1473e442009-02-24 14:15:08 -05001474
Steven Rostedt6ecc2d12009-02-27 21:33:02 -05001475 /*
1476 * If the trace point header did not define TRACE_SYSTEM
1477 * then the system would be called "TRACE_SYSTEM".
1478 */
Steven Rostedtae63b312012-05-03 23:09:03 -04001479 if (strcmp(call->class->system, TRACE_SYSTEM) != 0) {
1480 d_events = event_subsystem_dir(tr, call->class->system, file, parent);
1481 if (!d_events)
1482 return -ENOMEM;
1483 } else
1484 d_events = parent;
Steven Rostedt6ecc2d12009-02-27 21:33:02 -05001485
Steven Rostedtae63b312012-05-03 23:09:03 -04001486 file->dir = debugfs_create_dir(call->name, d_events);
1487 if (!file->dir) {
1488 pr_warning("Could not create debugfs '%s' directory\n",
1489 call->name);
Steven Rostedt1473e442009-02-24 14:15:08 -05001490 return -1;
1491 }
1492
Steven Rostedt9b637762012-05-10 15:55:43 -04001493 if (call->class->reg && !(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE))
Steven Rostedtae63b312012-05-03 23:09:03 -04001494 trace_create_file("enable", 0644, file->dir, file,
Frederic Weisbeckerf3f3f002009-09-24 15:27:41 +02001495 enable);
Steven Rostedt1473e442009-02-24 14:15:08 -05001496
Steven Rostedt22392912010-04-21 12:27:06 -04001497#ifdef CONFIG_PERF_EVENTS
Steven Rostedta1d0ce82010-06-08 11:22:06 -04001498 if (call->event.type && call->class->reg)
Steven Rostedtae63b312012-05-03 23:09:03 -04001499 trace_create_file("id", 0444, file->dir, call,
Frederic Weisbeckerf3f3f002009-09-24 15:27:41 +02001500 id);
Steven Rostedt22392912010-04-21 12:27:06 -04001501#endif
Peter Zijlstra23725ae2009-03-19 20:26:13 +01001502
Li Zefanc9d932c2010-05-24 16:24:28 +08001503 /*
1504 * Other events may have the same class. Only update
1505 * the fields if they are not already defined.
1506 */
1507 head = trace_get_fields(call);
1508 if (list_empty(head)) {
1509 ret = call->class->define_fields(call);
1510 if (ret < 0) {
1511 pr_warning("Could not initialize trace point"
1512 " events/%s\n", call->name);
Steven Rostedtae63b312012-05-03 23:09:03 -04001513 return -1;
Tom Zanussicf027f62009-03-22 03:30:39 -05001514 }
1515 }
Steven Rostedtae63b312012-05-03 23:09:03 -04001516 trace_create_file("filter", 0644, file->dir, call,
Li Zefanc9d932c2010-05-24 16:24:28 +08001517 filter);
Tom Zanussicf027f62009-03-22 03:30:39 -05001518
Steven Rostedtae63b312012-05-03 23:09:03 -04001519 trace_create_file("format", 0444, file->dir, call,
Frederic Weisbeckerf3f3f002009-09-24 15:27:41 +02001520 format);
Steven Rostedtfd994982009-02-28 02:41:25 -05001521
Steven Rostedt1473e442009-02-24 14:15:08 -05001522 return 0;
1523}
1524
Steven Rostedtae63b312012-05-03 23:09:03 -04001525static void remove_subsystem(struct ftrace_subsystem_dir *dir)
1526{
1527 if (!dir)
1528 return;
1529
1530 if (!--dir->nr_events) {
1531 debugfs_remove_recursive(dir->entry);
1532 list_del(&dir->list);
1533 __put_system_dir(dir);
1534 }
1535}
1536
1537static void remove_event_from_tracers(struct ftrace_event_call *call)
1538{
1539 struct ftrace_event_file *file;
1540 struct trace_array *tr;
1541
1542 do_for_each_event_file_safe(tr, file) {
1543
1544 if (file->event_call != call)
1545 continue;
1546
1547 list_del(&file->list);
1548 debugfs_remove_recursive(file->dir);
1549 remove_subsystem(file->system);
Steven Rostedtd1a29142013-02-27 20:23:57 -05001550 kmem_cache_free(file_cachep, file);
Steven Rostedtae63b312012-05-03 23:09:03 -04001551
1552 /*
1553 * The do_for_each_event_file_safe() is
1554 * a double loop. After finding the call for this
1555 * trace_array, we use break to jump to the next
1556 * trace_array.
1557 */
1558 break;
1559 } while_for_each_event_file();
1560}
1561
Ezequiel Garcia87819152012-09-12 11:47:57 -03001562static void event_remove(struct ftrace_event_call *call)
1563{
Steven Rostedtae63b312012-05-03 23:09:03 -04001564 struct trace_array *tr;
1565 struct ftrace_event_file *file;
1566
1567 do_for_each_event_file(tr, file) {
1568 if (file->event_call != call)
1569 continue;
1570 ftrace_event_enable_disable(file, 0);
1571 /*
1572 * The do_for_each_event_file() is
1573 * a double loop. After finding the call for this
1574 * trace_array, we use break to jump to the next
1575 * trace_array.
1576 */
1577 break;
1578 } while_for_each_event_file();
1579
Ezequiel Garcia87819152012-09-12 11:47:57 -03001580 if (call->event.funcs)
1581 __unregister_ftrace_event(&call->event);
Steven Rostedtae63b312012-05-03 23:09:03 -04001582 remove_event_from_tracers(call);
Ezequiel Garcia87819152012-09-12 11:47:57 -03001583 list_del(&call->list);
1584}
1585
1586static int event_init(struct ftrace_event_call *call)
1587{
1588 int ret = 0;
1589
1590 if (WARN_ON(!call->name))
1591 return -EINVAL;
1592
1593 if (call->class->raw_init) {
1594 ret = call->class->raw_init(call);
1595 if (ret < 0 && ret != -ENOSYS)
1596 pr_warn("Could not initialize trace events/%s\n",
1597 call->name);
1598 }
1599
1600 return ret;
1601}
1602
Li Zefan67ead0a2010-05-24 16:25:13 +08001603static int
Steven Rostedtae63b312012-05-03 23:09:03 -04001604__register_event(struct ftrace_event_call *call, struct module *mod)
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001605{
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001606 int ret;
Steven Rostedt6d723732009-04-10 14:53:50 -04001607
Ezequiel Garcia87819152012-09-12 11:47:57 -03001608 ret = event_init(call);
1609 if (ret < 0)
1610 return ret;
Steven Rostedt701970b2009-04-24 23:11:22 -04001611
Steven Rostedtae63b312012-05-03 23:09:03 -04001612 list_add(&call->list, &ftrace_events);
Li Zefan67ead0a2010-05-24 16:25:13 +08001613 call->mod = mod;
Masami Hiramatsu88f70d72009-09-25 11:20:54 -07001614
Steven Rostedtae63b312012-05-03 23:09:03 -04001615 return 0;
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001616}
1617
Steven Rostedt (Red Hat)da511bf2013-05-09 15:00:07 -04001618static struct ftrace_event_file *
1619trace_create_new_event(struct ftrace_event_call *call,
1620 struct trace_array *tr)
1621{
1622 struct ftrace_event_file *file;
1623
1624 file = kmem_cache_alloc(file_cachep, GFP_TRACE);
1625 if (!file)
1626 return NULL;
1627
1628 file->event_call = call;
1629 file->tr = tr;
1630 atomic_set(&file->sm_ref, 0);
1631 list_add(&file->list, &tr->events);
1632
1633 return file;
1634}
1635
Steven Rostedtae63b312012-05-03 23:09:03 -04001636/* Add an event to a trace directory */
1637static int
1638__trace_add_new_event(struct ftrace_event_call *call,
1639 struct trace_array *tr,
1640 const struct file_operations *id,
1641 const struct file_operations *enable,
1642 const struct file_operations *filter,
1643 const struct file_operations *format)
1644{
1645 struct ftrace_event_file *file;
1646
Steven Rostedt (Red Hat)da511bf2013-05-09 15:00:07 -04001647 file = trace_create_new_event(call, tr);
Steven Rostedtae63b312012-05-03 23:09:03 -04001648 if (!file)
1649 return -ENOMEM;
1650
Steven Rostedtae63b312012-05-03 23:09:03 -04001651 return event_create_dir(tr->event_dir, file, id, enable, filter, format);
1652}
1653
Steven Rostedt77248222013-02-27 16:28:06 -05001654/*
1655 * Just create a decriptor for early init. A descriptor is required
1656 * for enabling events at boot. We want to enable events before
1657 * the filesystem is initialized.
1658 */
1659static __init int
1660__trace_early_add_new_event(struct ftrace_event_call *call,
1661 struct trace_array *tr)
1662{
1663 struct ftrace_event_file *file;
1664
Steven Rostedt (Red Hat)da511bf2013-05-09 15:00:07 -04001665 file = trace_create_new_event(call, tr);
Steven Rostedt77248222013-02-27 16:28:06 -05001666 if (!file)
1667 return -ENOMEM;
1668
Steven Rostedt77248222013-02-27 16:28:06 -05001669 return 0;
1670}
1671
Steven Rostedtae63b312012-05-03 23:09:03 -04001672struct ftrace_module_file_ops;
1673static void __add_event_to_tracers(struct ftrace_event_call *call,
1674 struct ftrace_module_file_ops *file_ops);
1675
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001676/* Add an additional event_call dynamically */
1677int trace_add_event_call(struct ftrace_event_call *call)
1678{
1679 int ret;
Alexander Z Lama8227412013-07-01 19:37:54 -07001680 mutex_lock(&trace_types_lock);
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001681 mutex_lock(&event_mutex);
Steven Rostedtae63b312012-05-03 23:09:03 -04001682
1683 ret = __register_event(call, NULL);
1684 if (ret >= 0)
1685 __add_event_to_tracers(call, NULL);
1686
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001687 mutex_unlock(&event_mutex);
Alexander Z Lama8227412013-07-01 19:37:54 -07001688 mutex_unlock(&trace_types_lock);
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001689 return ret;
1690}
Steven Rostedt701970b2009-04-24 23:11:22 -04001691
Masami Hiramatsu4fead8e2009-09-14 16:49:12 -04001692/*
Alexander Z Lama8227412013-07-01 19:37:54 -07001693 * Must be called under locking of trace_types_lock, event_mutex and
1694 * trace_event_sem.
Masami Hiramatsu4fead8e2009-09-14 16:49:12 -04001695 */
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001696static void __trace_remove_event_call(struct ftrace_event_call *call)
1697{
Ezequiel Garcia87819152012-09-12 11:47:57 -03001698 event_remove(call);
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001699 trace_destroy_fields(call);
1700 destroy_preds(call);
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001701}
1702
1703/* Remove an event_call */
1704void trace_remove_event_call(struct ftrace_event_call *call)
1705{
Alexander Z Lama8227412013-07-01 19:37:54 -07001706 mutex_lock(&trace_types_lock);
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001707 mutex_lock(&event_mutex);
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08001708 down_write(&trace_event_sem);
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001709 __trace_remove_event_call(call);
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08001710 up_write(&trace_event_sem);
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001711 mutex_unlock(&event_mutex);
Alexander Z Lama8227412013-07-01 19:37:54 -07001712 mutex_unlock(&trace_types_lock);
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001713}
1714
1715#define for_each_event(event, start, end) \
1716 for (event = start; \
1717 (unsigned long)event < (unsigned long)end; \
1718 event++)
1719
1720#ifdef CONFIG_MODULES
1721
1722static LIST_HEAD(ftrace_module_file_list);
1723
1724/*
1725 * Modules must own their file_operations to keep up with
1726 * reference counting.
1727 */
1728struct ftrace_module_file_ops {
1729 struct list_head list;
1730 struct module *mod;
1731 struct file_operations id;
1732 struct file_operations enable;
1733 struct file_operations format;
1734 struct file_operations filter;
1735};
1736
Steven Rostedt (Red Hat)315326c2013-03-02 17:37:14 -05001737static struct ftrace_module_file_ops *
1738find_ftrace_file_ops(struct ftrace_module_file_ops *file_ops, struct module *mod)
Steven Rostedtae63b312012-05-03 23:09:03 -04001739{
Steven Rostedt (Red Hat)315326c2013-03-02 17:37:14 -05001740 /*
1741 * As event_calls are added in groups by module,
1742 * when we find one file_ops, we don't need to search for
1743 * each call in that module, as the rest should be the
1744 * same. Only search for a new one if the last one did
1745 * not match.
1746 */
1747 if (file_ops && mod == file_ops->mod)
1748 return file_ops;
Steven Rostedtae63b312012-05-03 23:09:03 -04001749
1750 list_for_each_entry(file_ops, &ftrace_module_file_list, list) {
1751 if (file_ops->mod == mod)
1752 return file_ops;
1753 }
1754 return NULL;
1755}
1756
Steven Rostedt701970b2009-04-24 23:11:22 -04001757static struct ftrace_module_file_ops *
1758trace_create_file_ops(struct module *mod)
1759{
1760 struct ftrace_module_file_ops *file_ops;
1761
1762 /*
1763 * This is a bit of a PITA. To allow for correct reference
1764 * counting, modules must "own" their file_operations.
1765 * To do this, we allocate the file operations that will be
1766 * used in the event directory.
1767 */
1768
1769 file_ops = kmalloc(sizeof(*file_ops), GFP_KERNEL);
1770 if (!file_ops)
1771 return NULL;
1772
1773 file_ops->mod = mod;
1774
1775 file_ops->id = ftrace_event_id_fops;
1776 file_ops->id.owner = mod;
1777
1778 file_ops->enable = ftrace_enable_fops;
1779 file_ops->enable.owner = mod;
1780
1781 file_ops->filter = ftrace_event_filter_fops;
1782 file_ops->filter.owner = mod;
1783
1784 file_ops->format = ftrace_event_format_fops;
1785 file_ops->format.owner = mod;
1786
1787 list_add(&file_ops->list, &ftrace_module_file_list);
1788
1789 return file_ops;
1790}
1791
Steven Rostedt6d723732009-04-10 14:53:50 -04001792static void trace_module_add_events(struct module *mod)
1793{
Steven Rostedt701970b2009-04-24 23:11:22 -04001794 struct ftrace_module_file_ops *file_ops = NULL;
Steven Rostedte4a9ea52011-01-27 09:15:30 -05001795 struct ftrace_event_call **call, **start, **end;
Steven Rostedt6d723732009-04-10 14:53:50 -04001796
1797 start = mod->trace_events;
1798 end = mod->trace_events + mod->num_trace_events;
1799
1800 if (start == end)
1801 return;
1802
Li Zefan67ead0a2010-05-24 16:25:13 +08001803 file_ops = trace_create_file_ops(mod);
1804 if (!file_ops)
Steven Rostedt6d723732009-04-10 14:53:50 -04001805 return;
1806
1807 for_each_event(call, start, end) {
Steven Rostedtae63b312012-05-03 23:09:03 -04001808 __register_event(*call, mod);
1809 __add_event_to_tracers(*call, file_ops);
Steven Rostedt6d723732009-04-10 14:53:50 -04001810 }
1811}
1812
1813static void trace_module_remove_events(struct module *mod)
1814{
Steven Rostedt701970b2009-04-24 23:11:22 -04001815 struct ftrace_module_file_ops *file_ops;
Steven Rostedt6d723732009-04-10 14:53:50 -04001816 struct ftrace_event_call *call, *p;
Steven Rostedt (Red Hat)575380d2013-03-04 23:05:12 -05001817 bool clear_trace = false;
Steven Rostedt6d723732009-04-10 14:53:50 -04001818
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08001819 down_write(&trace_event_sem);
Steven Rostedt6d723732009-04-10 14:53:50 -04001820 list_for_each_entry_safe(call, p, &ftrace_events, list) {
1821 if (call->mod == mod) {
Steven Rostedt (Red Hat)575380d2013-03-04 23:05:12 -05001822 if (call->flags & TRACE_EVENT_FL_WAS_ENABLED)
1823 clear_trace = true;
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001824 __trace_remove_event_call(call);
Steven Rostedt6d723732009-04-10 14:53:50 -04001825 }
1826 }
Steven Rostedt701970b2009-04-24 23:11:22 -04001827
1828 /* Now free the file_operations */
1829 list_for_each_entry(file_ops, &ftrace_module_file_list, list) {
1830 if (file_ops->mod == mod)
1831 break;
1832 }
1833 if (&file_ops->list != &ftrace_module_file_list) {
1834 list_del(&file_ops->list);
1835 kfree(file_ops);
1836 }
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08001837 up_write(&trace_event_sem);
Steven Rostedt9456f0f2009-05-06 21:54:09 -04001838
1839 /*
1840 * It is safest to reset the ring buffer if the module being unloaded
Steven Rostedt (Red Hat)873c6422013-03-04 23:26:06 -05001841 * registered any events that were used. The only worry is if
1842 * a new module gets loaded, and takes on the same id as the events
1843 * of this module. When printing out the buffer, traced events left
1844 * over from this module may be passed to the new module events and
1845 * unexpected results may occur.
Steven Rostedt9456f0f2009-05-06 21:54:09 -04001846 */
Steven Rostedt (Red Hat)575380d2013-03-04 23:05:12 -05001847 if (clear_trace)
Steven Rostedt (Red Hat)873c6422013-03-04 23:26:06 -05001848 tracing_reset_all_online_cpus();
Steven Rostedt6d723732009-04-10 14:53:50 -04001849}
1850
Steven Rostedt61f919a2009-04-14 18:22:32 -04001851static int trace_module_notify(struct notifier_block *self,
1852 unsigned long val, void *data)
Steven Rostedt6d723732009-04-10 14:53:50 -04001853{
1854 struct module *mod = data;
1855
Alexander Z Lama8227412013-07-01 19:37:54 -07001856 mutex_lock(&trace_types_lock);
Steven Rostedt6d723732009-04-10 14:53:50 -04001857 mutex_lock(&event_mutex);
1858 switch (val) {
1859 case MODULE_STATE_COMING:
1860 trace_module_add_events(mod);
1861 break;
1862 case MODULE_STATE_GOING:
1863 trace_module_remove_events(mod);
1864 break;
1865 }
1866 mutex_unlock(&event_mutex);
Alexander Z Lama8227412013-07-01 19:37:54 -07001867 mutex_unlock(&trace_types_lock);
Steven Rostedt6d723732009-04-10 14:53:50 -04001868
1869 return 0;
1870}
Steven Rostedt (Red Hat)315326c2013-03-02 17:37:14 -05001871
1872static int
1873__trace_add_new_mod_event(struct ftrace_event_call *call,
1874 struct trace_array *tr,
1875 struct ftrace_module_file_ops *file_ops)
1876{
1877 return __trace_add_new_event(call, tr,
1878 &file_ops->id, &file_ops->enable,
1879 &file_ops->filter, &file_ops->format);
1880}
1881
Steven Rostedt61f919a2009-04-14 18:22:32 -04001882#else
Steven Rostedt (Red Hat)315326c2013-03-02 17:37:14 -05001883static inline struct ftrace_module_file_ops *
1884find_ftrace_file_ops(struct ftrace_module_file_ops *file_ops, struct module *mod)
Steven Rostedtae63b312012-05-03 23:09:03 -04001885{
1886 return NULL;
1887}
Steven Rostedt (Red Hat)315326c2013-03-02 17:37:14 -05001888static inline int trace_module_notify(struct notifier_block *self,
1889 unsigned long val, void *data)
Steven Rostedt61f919a2009-04-14 18:22:32 -04001890{
1891 return 0;
1892}
Steven Rostedt (Red Hat)315326c2013-03-02 17:37:14 -05001893static inline int
1894__trace_add_new_mod_event(struct ftrace_event_call *call,
1895 struct trace_array *tr,
1896 struct ftrace_module_file_ops *file_ops)
1897{
1898 return -ENODEV;
1899}
Steven Rostedt61f919a2009-04-14 18:22:32 -04001900#endif /* CONFIG_MODULES */
Steven Rostedt6d723732009-04-10 14:53:50 -04001901
Steven Rostedtae63b312012-05-03 23:09:03 -04001902/* Create a new event directory structure for a trace directory. */
1903static void
1904__trace_add_event_dirs(struct trace_array *tr)
1905{
1906 struct ftrace_module_file_ops *file_ops = NULL;
1907 struct ftrace_event_call *call;
1908 int ret;
1909
1910 list_for_each_entry(call, &ftrace_events, list) {
1911 if (call->mod) {
1912 /*
1913 * Directories for events by modules need to
1914 * keep module ref counts when opened (as we don't
1915 * want the module to disappear when reading one
1916 * of these files). The file_ops keep account of
1917 * the module ref count.
Steven Rostedtae63b312012-05-03 23:09:03 -04001918 */
Steven Rostedt (Red Hat)315326c2013-03-02 17:37:14 -05001919 file_ops = find_ftrace_file_ops(file_ops, call->mod);
Steven Rostedtae63b312012-05-03 23:09:03 -04001920 if (!file_ops)
1921 continue; /* Warn? */
Steven Rostedt (Red Hat)315326c2013-03-02 17:37:14 -05001922 ret = __trace_add_new_mod_event(call, tr, file_ops);
Steven Rostedtae63b312012-05-03 23:09:03 -04001923 if (ret < 0)
1924 pr_warning("Could not create directory for event %s\n",
1925 call->name);
1926 continue;
1927 }
1928 ret = __trace_add_new_event(call, tr,
1929 &ftrace_event_id_fops,
1930 &ftrace_enable_fops,
1931 &ftrace_event_filter_fops,
1932 &ftrace_event_format_fops);
1933 if (ret < 0)
1934 pr_warning("Could not create directory for event %s\n",
1935 call->name);
1936 }
1937}
1938
Steven Rostedt (Red Hat)3cd715d2013-03-12 19:35:13 -04001939#ifdef CONFIG_DYNAMIC_FTRACE
1940
1941/* Avoid typos */
1942#define ENABLE_EVENT_STR "enable_event"
1943#define DISABLE_EVENT_STR "disable_event"
1944
1945struct event_probe_data {
1946 struct ftrace_event_file *file;
1947 unsigned long count;
1948 int ref;
1949 bool enable;
1950};
1951
1952static struct ftrace_event_file *
1953find_event_file(struct trace_array *tr, const char *system, const char *event)
1954{
1955 struct ftrace_event_file *file;
1956 struct ftrace_event_call *call;
1957
1958 list_for_each_entry(file, &tr->events, list) {
1959
1960 call = file->event_call;
1961
1962 if (!call->name || !call->class || !call->class->reg)
1963 continue;
1964
1965 if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
1966 continue;
1967
1968 if (strcmp(event, call->name) == 0 &&
1969 strcmp(system, call->class->system) == 0)
1970 return file;
1971 }
1972 return NULL;
1973}
1974
1975static void
1976event_enable_probe(unsigned long ip, unsigned long parent_ip, void **_data)
1977{
1978 struct event_probe_data **pdata = (struct event_probe_data **)_data;
1979 struct event_probe_data *data = *pdata;
1980
1981 if (!data)
1982 return;
1983
1984 if (data->enable)
1985 clear_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &data->file->flags);
1986 else
1987 set_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &data->file->flags);
1988}
1989
1990static void
1991event_enable_count_probe(unsigned long ip, unsigned long parent_ip, void **_data)
1992{
1993 struct event_probe_data **pdata = (struct event_probe_data **)_data;
1994 struct event_probe_data *data = *pdata;
1995
1996 if (!data)
1997 return;
1998
1999 if (!data->count)
2000 return;
2001
2002 /* Skip if the event is in a state we want to switch to */
2003 if (data->enable == !(data->file->flags & FTRACE_EVENT_FL_SOFT_DISABLED))
2004 return;
2005
2006 if (data->count != -1)
2007 (data->count)--;
2008
2009 event_enable_probe(ip, parent_ip, _data);
2010}
2011
2012static int
2013event_enable_print(struct seq_file *m, unsigned long ip,
2014 struct ftrace_probe_ops *ops, void *_data)
2015{
2016 struct event_probe_data *data = _data;
2017
2018 seq_printf(m, "%ps:", (void *)ip);
2019
2020 seq_printf(m, "%s:%s:%s",
2021 data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR,
2022 data->file->event_call->class->system,
2023 data->file->event_call->name);
2024
2025 if (data->count == -1)
2026 seq_printf(m, ":unlimited\n");
2027 else
2028 seq_printf(m, ":count=%ld\n", data->count);
2029
2030 return 0;
2031}
2032
2033static int
2034event_enable_init(struct ftrace_probe_ops *ops, unsigned long ip,
2035 void **_data)
2036{
2037 struct event_probe_data **pdata = (struct event_probe_data **)_data;
2038 struct event_probe_data *data = *pdata;
2039
2040 data->ref++;
2041 return 0;
2042}
2043
2044static void
2045event_enable_free(struct ftrace_probe_ops *ops, unsigned long ip,
2046 void **_data)
2047{
2048 struct event_probe_data **pdata = (struct event_probe_data **)_data;
2049 struct event_probe_data *data = *pdata;
2050
2051 if (WARN_ON_ONCE(data->ref <= 0))
2052 return;
2053
2054 data->ref--;
2055 if (!data->ref) {
2056 /* Remove the SOFT_MODE flag */
2057 __ftrace_event_enable_disable(data->file, 0, 1);
2058 module_put(data->file->event_call->mod);
2059 kfree(data);
2060 }
2061 *pdata = NULL;
2062}
2063
2064static struct ftrace_probe_ops event_enable_probe_ops = {
2065 .func = event_enable_probe,
2066 .print = event_enable_print,
2067 .init = event_enable_init,
2068 .free = event_enable_free,
2069};
2070
2071static struct ftrace_probe_ops event_enable_count_probe_ops = {
2072 .func = event_enable_count_probe,
2073 .print = event_enable_print,
2074 .init = event_enable_init,
2075 .free = event_enable_free,
2076};
2077
2078static struct ftrace_probe_ops event_disable_probe_ops = {
2079 .func = event_enable_probe,
2080 .print = event_enable_print,
2081 .init = event_enable_init,
2082 .free = event_enable_free,
2083};
2084
2085static struct ftrace_probe_ops event_disable_count_probe_ops = {
2086 .func = event_enable_count_probe,
2087 .print = event_enable_print,
2088 .init = event_enable_init,
2089 .free = event_enable_free,
2090};
2091
2092static int
2093event_enable_func(struct ftrace_hash *hash,
2094 char *glob, char *cmd, char *param, int enabled)
2095{
2096 struct trace_array *tr = top_trace_array();
2097 struct ftrace_event_file *file;
2098 struct ftrace_probe_ops *ops;
2099 struct event_probe_data *data;
2100 const char *system;
2101 const char *event;
2102 char *number;
2103 bool enable;
2104 int ret;
2105
2106 /* hash funcs only work with set_ftrace_filter */
Harsh Prateek Bora8092e802013-05-24 12:52:17 +05302107 if (!enabled || !param)
Steven Rostedt (Red Hat)3cd715d2013-03-12 19:35:13 -04002108 return -EINVAL;
2109
2110 system = strsep(&param, ":");
2111 if (!param)
2112 return -EINVAL;
2113
2114 event = strsep(&param, ":");
2115
2116 mutex_lock(&event_mutex);
2117
2118 ret = -EINVAL;
2119 file = find_event_file(tr, system, event);
2120 if (!file)
2121 goto out;
2122
2123 enable = strcmp(cmd, ENABLE_EVENT_STR) == 0;
2124
2125 if (enable)
2126 ops = param ? &event_enable_count_probe_ops : &event_enable_probe_ops;
2127 else
2128 ops = param ? &event_disable_count_probe_ops : &event_disable_probe_ops;
2129
2130 if (glob[0] == '!') {
2131 unregister_ftrace_function_probe_func(glob+1, ops);
2132 ret = 0;
2133 goto out;
2134 }
2135
2136 ret = -ENOMEM;
2137 data = kzalloc(sizeof(*data), GFP_KERNEL);
2138 if (!data)
2139 goto out;
2140
2141 data->enable = enable;
2142 data->count = -1;
2143 data->file = file;
2144
2145 if (!param)
2146 goto out_reg;
2147
2148 number = strsep(&param, ":");
2149
2150 ret = -EINVAL;
2151 if (!strlen(number))
2152 goto out_free;
2153
2154 /*
2155 * We use the callback data field (which is a pointer)
2156 * as our counter.
2157 */
2158 ret = kstrtoul(number, 0, &data->count);
2159 if (ret)
2160 goto out_free;
2161
2162 out_reg:
2163 /* Don't let event modules unload while probe registered */
2164 ret = try_module_get(file->event_call->mod);
Masami Hiramatsu6ed01062013-05-16 20:48:49 +09002165 if (!ret) {
2166 ret = -EBUSY;
Steven Rostedt (Red Hat)3cd715d2013-03-12 19:35:13 -04002167 goto out_free;
Masami Hiramatsu6ed01062013-05-16 20:48:49 +09002168 }
Steven Rostedt (Red Hat)3cd715d2013-03-12 19:35:13 -04002169
2170 ret = __ftrace_event_enable_disable(file, 1, 1);
2171 if (ret < 0)
2172 goto out_put;
2173 ret = register_ftrace_function_probe(glob, ops, data);
Steven Rostedt (Red Hat)ff305de2013-05-09 11:30:26 -04002174 /*
2175 * The above returns on success the # of functions enabled,
2176 * but if it didn't find any functions it returns zero.
2177 * Consider no functions a failure too.
2178 */
Masami Hiramatsua5b85bd2013-05-09 14:44:14 +09002179 if (!ret) {
2180 ret = -ENOENT;
Steven Rostedt (Red Hat)3cd715d2013-03-12 19:35:13 -04002181 goto out_disable;
Steven Rostedt (Red Hat)ff305de2013-05-09 11:30:26 -04002182 } else if (ret < 0)
2183 goto out_disable;
2184 /* Just return zero, not the number of enabled functions */
2185 ret = 0;
Steven Rostedt (Red Hat)3cd715d2013-03-12 19:35:13 -04002186 out:
2187 mutex_unlock(&event_mutex);
2188 return ret;
2189
2190 out_disable:
2191 __ftrace_event_enable_disable(file, 0, 1);
2192 out_put:
2193 module_put(file->event_call->mod);
2194 out_free:
2195 kfree(data);
2196 goto out;
2197}
2198
2199static struct ftrace_func_command event_enable_cmd = {
2200 .name = ENABLE_EVENT_STR,
2201 .func = event_enable_func,
2202};
2203
2204static struct ftrace_func_command event_disable_cmd = {
2205 .name = DISABLE_EVENT_STR,
2206 .func = event_enable_func,
2207};
2208
2209static __init int register_event_cmds(void)
2210{
2211 int ret;
2212
2213 ret = register_ftrace_command(&event_enable_cmd);
2214 if (WARN_ON(ret < 0))
2215 return ret;
2216 ret = register_ftrace_command(&event_disable_cmd);
2217 if (WARN_ON(ret < 0))
2218 unregister_ftrace_command(&event_enable_cmd);
2219 return ret;
2220}
2221#else
2222static inline int register_event_cmds(void) { return 0; }
2223#endif /* CONFIG_DYNAMIC_FTRACE */
2224
Steven Rostedt77248222013-02-27 16:28:06 -05002225/*
2226 * The top level array has already had its ftrace_event_file
2227 * descriptors created in order to allow for early events to
2228 * be recorded. This function is called after the debugfs has been
2229 * initialized, and we now have to create the files associated
2230 * to the events.
2231 */
2232static __init void
2233__trace_early_add_event_dirs(struct trace_array *tr)
2234{
2235 struct ftrace_event_file *file;
2236 int ret;
2237
2238
2239 list_for_each_entry(file, &tr->events, list) {
2240 ret = event_create_dir(tr->event_dir, file,
2241 &ftrace_event_id_fops,
2242 &ftrace_enable_fops,
2243 &ftrace_event_filter_fops,
2244 &ftrace_event_format_fops);
2245 if (ret < 0)
2246 pr_warning("Could not create directory for event %s\n",
2247 file->event_call->name);
2248 }
2249}
2250
2251/*
2252 * For early boot up, the top trace array requires to have
2253 * a list of events that can be enabled. This must be done before
2254 * the filesystem is set up in order to allow events to be traced
2255 * early.
2256 */
2257static __init void
2258__trace_early_add_events(struct trace_array *tr)
2259{
2260 struct ftrace_event_call *call;
2261 int ret;
2262
2263 list_for_each_entry(call, &ftrace_events, list) {
2264 /* Early boot up should not have any modules loaded */
2265 if (WARN_ON_ONCE(call->mod))
2266 continue;
2267
2268 ret = __trace_early_add_new_event(call, tr);
2269 if (ret < 0)
2270 pr_warning("Could not create early event %s\n",
2271 call->name);
2272 }
2273}
2274
Steven Rostedt0c8916c2012-08-07 16:14:16 -04002275/* Remove the event directory structure for a trace directory. */
2276static void
2277__trace_remove_event_dirs(struct trace_array *tr)
2278{
2279 struct ftrace_event_file *file, *next;
2280
2281 list_for_each_entry_safe(file, next, &tr->events, list) {
2282 list_del(&file->list);
2283 debugfs_remove_recursive(file->dir);
2284 remove_subsystem(file->system);
Steven Rostedtd1a29142013-02-27 20:23:57 -05002285 kmem_cache_free(file_cachep, file);
Steven Rostedt0c8916c2012-08-07 16:14:16 -04002286 }
2287}
2288
Steven Rostedtae63b312012-05-03 23:09:03 -04002289static void
2290__add_event_to_tracers(struct ftrace_event_call *call,
2291 struct ftrace_module_file_ops *file_ops)
2292{
2293 struct trace_array *tr;
2294
2295 list_for_each_entry(tr, &ftrace_trace_arrays, list) {
2296 if (file_ops)
Steven Rostedt (Red Hat)315326c2013-03-02 17:37:14 -05002297 __trace_add_new_mod_event(call, tr, file_ops);
Steven Rostedtae63b312012-05-03 23:09:03 -04002298 else
2299 __trace_add_new_event(call, tr,
2300 &ftrace_event_id_fops,
2301 &ftrace_enable_fops,
2302 &ftrace_event_filter_fops,
2303 &ftrace_event_format_fops);
2304 }
2305}
2306
Steven Rostedtec827c72009-09-14 10:50:23 -04002307static struct notifier_block trace_module_nb = {
Steven Rostedt6d723732009-04-10 14:53:50 -04002308 .notifier_call = trace_module_notify,
2309 .priority = 0,
2310};
2311
Steven Rostedte4a9ea52011-01-27 09:15:30 -05002312extern struct ftrace_event_call *__start_ftrace_events[];
2313extern struct ftrace_event_call *__stop_ftrace_events[];
Steven Rostedta59fd602009-04-10 13:52:20 -04002314
Li Zefan020e5f82009-07-01 10:47:05 +08002315static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata;
2316
2317static __init int setup_trace_event(char *str)
2318{
2319 strlcpy(bootup_event_buf, str, COMMAND_LINE_SIZE);
Steven Rostedt (Red Hat)55034cd2013-03-07 22:48:09 -05002320 ring_buffer_expanded = true;
2321 tracing_selftest_disabled = true;
Li Zefan020e5f82009-07-01 10:47:05 +08002322
2323 return 1;
2324}
2325__setup("trace_event=", setup_trace_event);
2326
Steven Rostedt77248222013-02-27 16:28:06 -05002327/* Expects to have event_mutex held when called */
2328static int
2329create_event_toplevel_files(struct dentry *parent, struct trace_array *tr)
Steven Rostedtae63b312012-05-03 23:09:03 -04002330{
2331 struct dentry *d_events;
2332 struct dentry *entry;
2333
2334 entry = debugfs_create_file("set_event", 0644, parent,
2335 tr, &ftrace_set_event_fops);
2336 if (!entry) {
2337 pr_warning("Could not create debugfs 'set_event' entry\n");
2338 return -ENOMEM;
2339 }
2340
2341 d_events = debugfs_create_dir("events", parent);
Steven Rostedt277ba042012-08-03 16:10:49 -04002342 if (!d_events) {
Steven Rostedtae63b312012-05-03 23:09:03 -04002343 pr_warning("Could not create debugfs 'events' directory\n");
Steven Rostedt277ba042012-08-03 16:10:49 -04002344 return -ENOMEM;
2345 }
Steven Rostedtae63b312012-05-03 23:09:03 -04002346
2347 /* ring buffer internal formats */
2348 trace_create_file("header_page", 0444, d_events,
2349 ring_buffer_print_page_header,
2350 &ftrace_show_header_fops);
2351
2352 trace_create_file("header_event", 0444, d_events,
2353 ring_buffer_print_entry_header,
2354 &ftrace_show_header_fops);
2355
2356 trace_create_file("enable", 0644, d_events,
2357 tr, &ftrace_tr_enable_fops);
2358
2359 tr->event_dir = d_events;
Steven Rostedt77248222013-02-27 16:28:06 -05002360
2361 return 0;
2362}
2363
2364/**
2365 * event_trace_add_tracer - add a instance of a trace_array to events
2366 * @parent: The parent dentry to place the files/directories for events in
2367 * @tr: The trace array associated with these events
2368 *
2369 * When a new instance is created, it needs to set up its events
2370 * directory, as well as other files associated with events. It also
2371 * creates the event hierachry in the @parent/events directory.
2372 *
2373 * Returns 0 on success.
2374 */
2375int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr)
2376{
2377 int ret;
2378
2379 mutex_lock(&event_mutex);
2380
2381 ret = create_event_toplevel_files(parent, tr);
2382 if (ret)
2383 goto out_unlock;
2384
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08002385 down_write(&trace_event_sem);
Steven Rostedtae63b312012-05-03 23:09:03 -04002386 __trace_add_event_dirs(tr);
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08002387 up_write(&trace_event_sem);
Steven Rostedt277ba042012-08-03 16:10:49 -04002388
Steven Rostedt77248222013-02-27 16:28:06 -05002389 out_unlock:
Steven Rostedt277ba042012-08-03 16:10:49 -04002390 mutex_unlock(&event_mutex);
Steven Rostedtae63b312012-05-03 23:09:03 -04002391
Steven Rostedt77248222013-02-27 16:28:06 -05002392 return ret;
2393}
2394
2395/*
2396 * The top trace array already had its file descriptors created.
2397 * Now the files themselves need to be created.
2398 */
2399static __init int
2400early_event_add_tracer(struct dentry *parent, struct trace_array *tr)
2401{
2402 int ret;
2403
2404 mutex_lock(&event_mutex);
2405
2406 ret = create_event_toplevel_files(parent, tr);
2407 if (ret)
2408 goto out_unlock;
2409
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08002410 down_write(&trace_event_sem);
Steven Rostedt77248222013-02-27 16:28:06 -05002411 __trace_early_add_event_dirs(tr);
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08002412 up_write(&trace_event_sem);
Steven Rostedt77248222013-02-27 16:28:06 -05002413
2414 out_unlock:
2415 mutex_unlock(&event_mutex);
2416
2417 return ret;
Steven Rostedtae63b312012-05-03 23:09:03 -04002418}
2419
Steven Rostedt0c8916c2012-08-07 16:14:16 -04002420int event_trace_del_tracer(struct trace_array *tr)
2421{
Steven Rostedt0c8916c2012-08-07 16:14:16 -04002422 mutex_lock(&event_mutex);
2423
Steven Rostedt (Red Hat)2a6c24a2013-07-02 14:48:23 -04002424 /* Disable any running events */
2425 __ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0);
2426
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08002427 down_write(&trace_event_sem);
Steven Rostedt0c8916c2012-08-07 16:14:16 -04002428 __trace_remove_event_dirs(tr);
2429 debugfs_remove_recursive(tr->event_dir);
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08002430 up_write(&trace_event_sem);
Steven Rostedt0c8916c2012-08-07 16:14:16 -04002431
2432 tr->event_dir = NULL;
2433
2434 mutex_unlock(&event_mutex);
2435
2436 return 0;
2437}
2438
Steven Rostedtd1a29142013-02-27 20:23:57 -05002439static __init int event_trace_memsetup(void)
2440{
2441 field_cachep = KMEM_CACHE(ftrace_event_field, SLAB_PANIC);
2442 file_cachep = KMEM_CACHE(ftrace_event_file, SLAB_PANIC);
2443 return 0;
2444}
2445
Ezequiel Garcia87819152012-09-12 11:47:57 -03002446static __init int event_trace_enable(void)
2447{
Steven Rostedtae63b312012-05-03 23:09:03 -04002448 struct trace_array *tr = top_trace_array();
Ezequiel Garcia87819152012-09-12 11:47:57 -03002449 struct ftrace_event_call **iter, *call;
2450 char *buf = bootup_event_buf;
2451 char *token;
2452 int ret;
2453
2454 for_each_event(iter, __start_ftrace_events, __stop_ftrace_events) {
2455
2456 call = *iter;
2457 ret = event_init(call);
2458 if (!ret)
2459 list_add(&call->list, &ftrace_events);
2460 }
2461
Steven Rostedt77248222013-02-27 16:28:06 -05002462 /*
2463 * We need the top trace array to have a working set of trace
2464 * points at early init, before the debug files and directories
2465 * are created. Create the file entries now, and attach them
2466 * to the actual file dentries later.
2467 */
2468 __trace_early_add_events(tr);
2469
Ezequiel Garcia87819152012-09-12 11:47:57 -03002470 while (true) {
2471 token = strsep(&buf, ",");
2472
2473 if (!token)
2474 break;
2475 if (!*token)
2476 continue;
2477
Steven Rostedtae63b312012-05-03 23:09:03 -04002478 ret = ftrace_set_clr_event(tr, token, 1);
Ezequiel Garcia87819152012-09-12 11:47:57 -03002479 if (ret)
2480 pr_warn("Failed to enable trace event: %s\n", token);
2481 }
Steven Rostedt81698832012-10-11 10:15:05 -04002482
2483 trace_printk_start_comm();
2484
Steven Rostedt (Red Hat)3cd715d2013-03-12 19:35:13 -04002485 register_event_cmds();
2486
Ezequiel Garcia87819152012-09-12 11:47:57 -03002487 return 0;
2488}
2489
Steven Rostedtb77e38a2009-02-24 10:21:36 -05002490static __init int event_trace_init(void)
2491{
Steven Rostedtae63b312012-05-03 23:09:03 -04002492 struct trace_array *tr;
Steven Rostedtb77e38a2009-02-24 10:21:36 -05002493 struct dentry *d_tracer;
2494 struct dentry *entry;
Steven Rostedt6d723732009-04-10 14:53:50 -04002495 int ret;
Steven Rostedtb77e38a2009-02-24 10:21:36 -05002496
Steven Rostedtae63b312012-05-03 23:09:03 -04002497 tr = top_trace_array();
2498
Steven Rostedtb77e38a2009-02-24 10:21:36 -05002499 d_tracer = tracing_init_dentry();
2500 if (!d_tracer)
2501 return 0;
2502
Steven Rostedt2314c4a2009-03-10 12:04:02 -04002503 entry = debugfs_create_file("available_events", 0444, d_tracer,
Steven Rostedtae63b312012-05-03 23:09:03 -04002504 tr, &ftrace_avail_fops);
Steven Rostedt2314c4a2009-03-10 12:04:02 -04002505 if (!entry)
2506 pr_warning("Could not create debugfs "
2507 "'available_events' entry\n");
2508
Li Zefan8728fe52010-05-24 16:22:49 +08002509 if (trace_define_common_fields())
2510 pr_warning("tracing: Failed to allocate common fields");
2511
Steven Rostedt77248222013-02-27 16:28:06 -05002512 ret = early_event_add_tracer(d_tracer, tr);
Steven Rostedtae63b312012-05-03 23:09:03 -04002513 if (ret)
2514 return ret;
Li Zefan020e5f82009-07-01 10:47:05 +08002515
Steven Rostedt6d723732009-04-10 14:53:50 -04002516 ret = register_module_notifier(&trace_module_nb);
Ming Lei55379372009-05-18 23:04:46 +08002517 if (ret)
Steven Rostedt6d723732009-04-10 14:53:50 -04002518 pr_warning("Failed to register trace events module notifier\n");
2519
Steven Rostedtb77e38a2009-02-24 10:21:36 -05002520 return 0;
2521}
Steven Rostedtd1a29142013-02-27 20:23:57 -05002522early_initcall(event_trace_memsetup);
Ezequiel Garcia87819152012-09-12 11:47:57 -03002523core_initcall(event_trace_enable);
Steven Rostedtb77e38a2009-02-24 10:21:36 -05002524fs_initcall(event_trace_init);
Steven Rostedte6187002009-04-15 13:36:40 -04002525
2526#ifdef CONFIG_FTRACE_STARTUP_TEST
2527
2528static DEFINE_SPINLOCK(test_spinlock);
2529static DEFINE_SPINLOCK(test_spinlock_irq);
2530static DEFINE_MUTEX(test_mutex);
2531
2532static __init void test_work(struct work_struct *dummy)
2533{
2534 spin_lock(&test_spinlock);
2535 spin_lock_irq(&test_spinlock_irq);
2536 udelay(1);
2537 spin_unlock_irq(&test_spinlock_irq);
2538 spin_unlock(&test_spinlock);
2539
2540 mutex_lock(&test_mutex);
2541 msleep(1);
2542 mutex_unlock(&test_mutex);
2543}
2544
2545static __init int event_test_thread(void *unused)
2546{
2547 void *test_malloc;
2548
2549 test_malloc = kmalloc(1234, GFP_KERNEL);
2550 if (!test_malloc)
2551 pr_info("failed to kmalloc\n");
2552
2553 schedule_on_each_cpu(test_work);
2554
2555 kfree(test_malloc);
2556
2557 set_current_state(TASK_INTERRUPTIBLE);
2558 while (!kthread_should_stop())
2559 schedule();
2560
2561 return 0;
2562}
2563
2564/*
2565 * Do various things that may trigger events.
2566 */
2567static __init void event_test_stuff(void)
2568{
2569 struct task_struct *test_thread;
2570
2571 test_thread = kthread_run(event_test_thread, NULL, "test-events");
2572 msleep(1);
2573 kthread_stop(test_thread);
2574}
2575
2576/*
2577 * For every trace event defined, we will test each trace point separately,
2578 * and then by groups, and finally all trace points.
2579 */
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002580static __init void event_trace_self_tests(void)
Steven Rostedte6187002009-04-15 13:36:40 -04002581{
Steven Rostedtae63b312012-05-03 23:09:03 -04002582 struct ftrace_subsystem_dir *dir;
2583 struct ftrace_event_file *file;
Steven Rostedte6187002009-04-15 13:36:40 -04002584 struct ftrace_event_call *call;
2585 struct event_subsystem *system;
Steven Rostedtae63b312012-05-03 23:09:03 -04002586 struct trace_array *tr;
Steven Rostedte6187002009-04-15 13:36:40 -04002587 int ret;
2588
Steven Rostedtae63b312012-05-03 23:09:03 -04002589 tr = top_trace_array();
2590
Steven Rostedte6187002009-04-15 13:36:40 -04002591 pr_info("Running tests on trace events:\n");
2592
Steven Rostedtae63b312012-05-03 23:09:03 -04002593 list_for_each_entry(file, &tr->events, list) {
2594
2595 call = file->event_call;
Steven Rostedte6187002009-04-15 13:36:40 -04002596
Steven Rostedt22392912010-04-21 12:27:06 -04002597 /* Only test those that have a probe */
2598 if (!call->class || !call->class->probe)
Steven Rostedte6187002009-04-15 13:36:40 -04002599 continue;
2600
Steven Rostedt1f5a6b42009-09-14 11:58:24 -04002601/*
2602 * Testing syscall events here is pretty useless, but
2603 * we still do it if configured. But this is time consuming.
2604 * What we really need is a user thread to perform the
2605 * syscalls as we test.
2606 */
2607#ifndef CONFIG_EVENT_TRACE_TEST_SYSCALLS
Steven Rostedt8f082012010-04-20 10:47:33 -04002608 if (call->class->system &&
2609 strcmp(call->class->system, "syscalls") == 0)
Steven Rostedt1f5a6b42009-09-14 11:58:24 -04002610 continue;
2611#endif
2612
Steven Rostedte6187002009-04-15 13:36:40 -04002613 pr_info("Testing event %s: ", call->name);
2614
2615 /*
2616 * If an event is already enabled, someone is using
2617 * it and the self test should not be on.
2618 */
Steven Rostedtae63b312012-05-03 23:09:03 -04002619 if (file->flags & FTRACE_EVENT_FL_ENABLED) {
Steven Rostedte6187002009-04-15 13:36:40 -04002620 pr_warning("Enabled event during self test!\n");
2621 WARN_ON_ONCE(1);
2622 continue;
2623 }
2624
Steven Rostedtae63b312012-05-03 23:09:03 -04002625 ftrace_event_enable_disable(file, 1);
Steven Rostedte6187002009-04-15 13:36:40 -04002626 event_test_stuff();
Steven Rostedtae63b312012-05-03 23:09:03 -04002627 ftrace_event_enable_disable(file, 0);
Steven Rostedte6187002009-04-15 13:36:40 -04002628
2629 pr_cont("OK\n");
2630 }
2631
2632 /* Now test at the sub system level */
2633
2634 pr_info("Running tests on trace event systems:\n");
2635
Steven Rostedtae63b312012-05-03 23:09:03 -04002636 list_for_each_entry(dir, &tr->systems, list) {
2637
2638 system = dir->subsystem;
Steven Rostedte6187002009-04-15 13:36:40 -04002639
2640 /* the ftrace system is special, skip it */
2641 if (strcmp(system->name, "ftrace") == 0)
2642 continue;
2643
2644 pr_info("Testing event system %s: ", system->name);
2645
Steven Rostedtae63b312012-05-03 23:09:03 -04002646 ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 1);
Steven Rostedte6187002009-04-15 13:36:40 -04002647 if (WARN_ON_ONCE(ret)) {
2648 pr_warning("error enabling system %s\n",
2649 system->name);
2650 continue;
2651 }
2652
2653 event_test_stuff();
2654
Steven Rostedtae63b312012-05-03 23:09:03 -04002655 ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 0);
Yuanhan Liu76bab1b2012-08-27 15:13:45 +08002656 if (WARN_ON_ONCE(ret)) {
Steven Rostedte6187002009-04-15 13:36:40 -04002657 pr_warning("error disabling system %s\n",
2658 system->name);
Yuanhan Liu76bab1b2012-08-27 15:13:45 +08002659 continue;
2660 }
Steven Rostedte6187002009-04-15 13:36:40 -04002661
2662 pr_cont("OK\n");
2663 }
2664
2665 /* Test with all events enabled */
2666
2667 pr_info("Running tests on all trace events:\n");
2668 pr_info("Testing all events: ");
2669
Steven Rostedtae63b312012-05-03 23:09:03 -04002670 ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 1);
Steven Rostedte6187002009-04-15 13:36:40 -04002671 if (WARN_ON_ONCE(ret)) {
Steven Rostedte6187002009-04-15 13:36:40 -04002672 pr_warning("error enabling all events\n");
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002673 return;
Steven Rostedte6187002009-04-15 13:36:40 -04002674 }
2675
2676 event_test_stuff();
2677
2678 /* reset sysname */
Steven Rostedtae63b312012-05-03 23:09:03 -04002679 ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 0);
Steven Rostedte6187002009-04-15 13:36:40 -04002680 if (WARN_ON_ONCE(ret)) {
2681 pr_warning("error disabling all events\n");
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002682 return;
Steven Rostedte6187002009-04-15 13:36:40 -04002683 }
2684
2685 pr_cont("OK\n");
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002686}
2687
2688#ifdef CONFIG_FUNCTION_TRACER
2689
Tejun Heo245b2e72009-06-24 15:13:48 +09002690static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable);
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002691
2692static void
Steven Rostedt2f5f6ad2011-08-08 16:57:47 -04002693function_test_events_call(unsigned long ip, unsigned long parent_ip,
Steven Rostedta1e2e312011-08-09 12:50:46 -04002694 struct ftrace_ops *op, struct pt_regs *pt_regs)
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002695{
2696 struct ring_buffer_event *event;
Steven Rostedte77405a2009-09-02 14:17:06 -04002697 struct ring_buffer *buffer;
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002698 struct ftrace_entry *entry;
2699 unsigned long flags;
2700 long disabled;
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002701 int cpu;
2702 int pc;
2703
2704 pc = preempt_count();
Steven Rostedt5168ae52010-06-03 09:36:50 -04002705 preempt_disable_notrace();
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002706 cpu = raw_smp_processor_id();
Tejun Heo245b2e72009-06-24 15:13:48 +09002707 disabled = atomic_inc_return(&per_cpu(ftrace_test_event_disable, cpu));
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002708
2709 if (disabled != 1)
2710 goto out;
2711
2712 local_save_flags(flags);
2713
Steven Rostedte77405a2009-09-02 14:17:06 -04002714 event = trace_current_buffer_lock_reserve(&buffer,
2715 TRACE_FN, sizeof(*entry),
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002716 flags, pc);
2717 if (!event)
2718 goto out;
2719 entry = ring_buffer_event_data(event);
2720 entry->ip = ip;
2721 entry->parent_ip = parent_ip;
2722
Steven Rostedt0d5c6e12012-11-01 20:54:21 -04002723 trace_buffer_unlock_commit(buffer, event, flags, pc);
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002724
2725 out:
Tejun Heo245b2e72009-06-24 15:13:48 +09002726 atomic_dec(&per_cpu(ftrace_test_event_disable, cpu));
Steven Rostedt5168ae52010-06-03 09:36:50 -04002727 preempt_enable_notrace();
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002728}
2729
2730static struct ftrace_ops trace_ops __initdata =
2731{
2732 .func = function_test_events_call,
Steven Rostedt47409742012-07-20 11:04:44 -04002733 .flags = FTRACE_OPS_FL_RECURSION_SAFE,
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002734};
2735
2736static __init void event_trace_self_test_with_function(void)
2737{
Steven Rostedt17bb6152011-05-23 15:27:46 -04002738 int ret;
2739 ret = register_ftrace_function(&trace_ops);
2740 if (WARN_ON(ret < 0)) {
2741 pr_info("Failed to enable function tracer for event tests\n");
2742 return;
2743 }
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002744 pr_info("Running tests again, along with the function tracer\n");
2745 event_trace_self_tests();
2746 unregister_ftrace_function(&trace_ops);
2747}
2748#else
2749static __init void event_trace_self_test_with_function(void)
2750{
2751}
2752#endif
2753
2754static __init int event_trace_self_tests_init(void)
2755{
Li Zefan020e5f82009-07-01 10:47:05 +08002756 if (!tracing_selftest_disabled) {
2757 event_trace_self_tests();
2758 event_trace_self_test_with_function();
2759 }
Steven Rostedte6187002009-04-15 13:36:40 -04002760
2761 return 0;
2762}
2763
Steven Rostedt28d20e22009-04-20 12:12:44 -04002764late_initcall(event_trace_self_tests_init);
Steven Rostedte6187002009-04-15 13:36:40 -04002765
2766#endif