1 #ifndef _LINUX_FTRACE_EVENT_H
2 #define _LINUX_FTRACE_EVENT_H
4 #include <linux/ring_buffer.h>
5 #include <linux/trace_seq.h>
6 #include <linux/percpu.h>
7 #include <linux/hardirq.h>
8 #include <linux/perf_event.h>
15 struct trace_print_flags
{
20 struct trace_print_flags_u64
{
21 unsigned long long mask
;
25 const char *ftrace_print_flags_seq(struct trace_seq
*p
, const char *delim
,
27 const struct trace_print_flags
*flag_array
);
29 const char *ftrace_print_symbols_seq(struct trace_seq
*p
, unsigned long val
,
30 const struct trace_print_flags
*symbol_array
);
32 #if BITS_PER_LONG == 32
33 const char *ftrace_print_symbols_seq_u64(struct trace_seq
*p
,
34 unsigned long long val
,
35 const struct trace_print_flags_u64
39 const char *ftrace_print_hex_seq(struct trace_seq
*p
,
40 const unsigned char *buf
, int len
);
42 struct trace_iterator
;
45 int ftrace_raw_output_prep(struct trace_iterator
*iter
,
46 struct trace_event
*event
);
49 * The trace entry - the most basic unit of tracing. This is what
50 * is printed in the end as a single line in the trace output, such as:
52 * bash-15816 [01] 235.197585: idle_cpu <- irq_enter
57 unsigned char preempt_count
;
61 #define FTRACE_MAX_EVENT \
62 ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)
65 * Trace iterator - used by printout routines who present trace
66 * results to users and which routines might sleep, etc:
68 struct trace_iterator
{
69 struct trace_array
*tr
;
71 struct trace_buffer
*trace_buffer
;
75 struct ring_buffer_iter
**buffer_iter
;
76 unsigned long iter_flags
;
78 /* trace_seq for __print_flags() and __print_symbolic() etc. */
79 struct trace_seq tmp_seq
;
81 cpumask_var_t started
;
83 /* it's true when current open file is snapshot */
86 /* The below is zeroed out in pipe_read */
88 struct trace_entry
*ent
;
89 unsigned long lost_events
;
98 /* All new field here will be zeroed out in pipe_read */
101 enum trace_iter_flags
{
102 TRACE_FILE_LAT_FMT
= 1,
103 TRACE_FILE_ANNOTATE
= 2,
104 TRACE_FILE_TIME_IN_NS
= 4,
108 typedef enum print_line_t (*trace_print_func
)(struct trace_iterator
*iter
,
109 int flags
, struct trace_event
*event
);
111 struct trace_event_functions
{
112 trace_print_func trace
;
113 trace_print_func raw
;
114 trace_print_func hex
;
115 trace_print_func binary
;
119 struct hlist_node node
;
120 struct list_head list
;
122 struct trace_event_functions
*funcs
;
125 extern int register_ftrace_event(struct trace_event
*event
);
126 extern int unregister_ftrace_event(struct trace_event
*event
);
128 /* Return values for print_line callback */
130 TRACE_TYPE_PARTIAL_LINE
= 0, /* Retry after flushing the seq */
131 TRACE_TYPE_HANDLED
= 1,
132 TRACE_TYPE_UNHANDLED
= 2, /* Relay to other output functions */
133 TRACE_TYPE_NO_CONSUME
= 3 /* Handled but ask to not consume */
136 void tracing_generic_entry_update(struct trace_entry
*entry
,
139 struct ftrace_event_file
;
141 struct ring_buffer_event
*
142 trace_event_buffer_lock_reserve(struct ring_buffer
**current_buffer
,
143 struct ftrace_event_file
*ftrace_file
,
144 int type
, unsigned long len
,
145 unsigned long flags
, int pc
);
146 struct ring_buffer_event
*
147 trace_current_buffer_lock_reserve(struct ring_buffer
**current_buffer
,
148 int type
, unsigned long len
,
149 unsigned long flags
, int pc
);
150 void trace_current_buffer_unlock_commit(struct ring_buffer
*buffer
,
151 struct ring_buffer_event
*event
,
152 unsigned long flags
, int pc
);
153 void trace_buffer_unlock_commit(struct ring_buffer
*buffer
,
154 struct ring_buffer_event
*event
,
155 unsigned long flags
, int pc
);
156 void trace_buffer_unlock_commit_regs(struct ring_buffer
*buffer
,
157 struct ring_buffer_event
*event
,
158 unsigned long flags
, int pc
,
159 struct pt_regs
*regs
);
160 void trace_current_buffer_discard_commit(struct ring_buffer
*buffer
,
161 struct ring_buffer_event
*event
);
163 void tracing_record_cmdline(struct task_struct
*tsk
);
169 TRACE_REG_UNREGISTER
,
170 #ifdef CONFIG_PERF_EVENTS
171 TRACE_REG_PERF_REGISTER
,
172 TRACE_REG_PERF_UNREGISTER
,
174 TRACE_REG_PERF_CLOSE
,
180 struct ftrace_event_call
;
182 struct ftrace_event_class
{
185 #ifdef CONFIG_PERF_EVENTS
188 int (*reg
)(struct ftrace_event_call
*event
,
189 enum trace_reg type
, void *data
);
190 int (*define_fields
)(struct ftrace_event_call
*);
191 struct list_head
*(*get_fields
)(struct ftrace_event_call
*);
192 struct list_head fields
;
193 int (*raw_init
)(struct ftrace_event_call
*);
196 extern int ftrace_event_reg(struct ftrace_event_call
*event
,
197 enum trace_reg type
, void *data
);
200 TRACE_EVENT_FL_FILTERED_BIT
,
201 TRACE_EVENT_FL_CAP_ANY_BIT
,
202 TRACE_EVENT_FL_NO_SET_FILTER_BIT
,
203 TRACE_EVENT_FL_IGNORE_ENABLE_BIT
,
204 TRACE_EVENT_FL_WAS_ENABLED_BIT
,
205 TRACE_EVENT_FL_USE_CALL_FILTER_BIT
,
210 * FILTERED - The event has a filter attached
211 * CAP_ANY - Any user can enable for perf
212 * NO_SET_FILTER - Set when filter has error and is to be ignored
213 * IGNORE_ENABLE - For ftrace internal events, do not enable with debugfs file
214 * WAS_ENABLED - Set and stays set when an event was ever enabled
215 * (used for module unloading, if a module event is enabled,
216 * it is best to clear the buffers that used it).
217 * USE_CALL_FILTER - For ftrace internal events, don't use file filter
220 TRACE_EVENT_FL_FILTERED
= (1 << TRACE_EVENT_FL_FILTERED_BIT
),
221 TRACE_EVENT_FL_CAP_ANY
= (1 << TRACE_EVENT_FL_CAP_ANY_BIT
),
222 TRACE_EVENT_FL_NO_SET_FILTER
= (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT
),
223 TRACE_EVENT_FL_IGNORE_ENABLE
= (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT
),
224 TRACE_EVENT_FL_WAS_ENABLED
= (1 << TRACE_EVENT_FL_WAS_ENABLED_BIT
),
225 TRACE_EVENT_FL_USE_CALL_FILTER
= (1 << TRACE_EVENT_FL_USE_CALL_FILTER_BIT
),
228 struct ftrace_event_call
{
229 struct list_head list
;
230 struct ftrace_event_class
*class;
232 struct trace_event event
;
233 const char *print_fmt
;
234 struct event_filter
*filter
;
235 struct list_head
*files
;
239 * bit 0: filter_active
240 * bit 1: allow trace by non root (cap any)
241 * bit 2: failed to apply filter
242 * bit 3: ftrace internal event (do not enable)
243 * bit 4: Event was enabled by module
244 * bit 5: use call filter rather than file filter
246 int flags
; /* static flags of different events */
248 #ifdef CONFIG_PERF_EVENTS
250 struct hlist_head __percpu
*perf_events
;
252 int (*perf_perm
)(struct ftrace_event_call
*,
253 struct perf_event
*);
258 struct ftrace_subsystem_dir
;
261 FTRACE_EVENT_FL_ENABLED_BIT
,
262 FTRACE_EVENT_FL_RECORDED_CMD_BIT
,
263 FTRACE_EVENT_FL_FILTERED_BIT
,
264 FTRACE_EVENT_FL_NO_SET_FILTER_BIT
,
265 FTRACE_EVENT_FL_SOFT_MODE_BIT
,
266 FTRACE_EVENT_FL_SOFT_DISABLED_BIT
,
270 * Ftrace event file flags:
271 * ENABLED - The event is enabled
272 * RECORDED_CMD - The comms should be recorded at sched_switch
273 * FILTERED - The event has a filter attached
274 * NO_SET_FILTER - Set when filter has error and is to be ignored
275 * SOFT_MODE - The event is enabled/disabled by SOFT_DISABLED
276 * SOFT_DISABLED - When set, do not trace the event (even though its
277 * tracepoint may be enabled)
280 FTRACE_EVENT_FL_ENABLED
= (1 << FTRACE_EVENT_FL_ENABLED_BIT
),
281 FTRACE_EVENT_FL_RECORDED_CMD
= (1 << FTRACE_EVENT_FL_RECORDED_CMD_BIT
),
282 FTRACE_EVENT_FL_FILTERED
= (1 << FTRACE_EVENT_FL_FILTERED_BIT
),
283 FTRACE_EVENT_FL_NO_SET_FILTER
= (1 << FTRACE_EVENT_FL_NO_SET_FILTER_BIT
),
284 FTRACE_EVENT_FL_SOFT_MODE
= (1 << FTRACE_EVENT_FL_SOFT_MODE_BIT
),
285 FTRACE_EVENT_FL_SOFT_DISABLED
= (1 << FTRACE_EVENT_FL_SOFT_DISABLED_BIT
),
288 struct ftrace_event_file
{
289 struct list_head list
;
290 struct ftrace_event_call
*event_call
;
291 struct event_filter
*filter
;
293 struct trace_array
*tr
;
294 struct ftrace_subsystem_dir
*system
;
299 * bit 1: enabled cmd record
300 * bit 2: enable/disable with the soft disable bit
301 * bit 3: soft disabled
303 * Note: The bits must be set atomically to prevent races
304 * from other writers. Reads of flags do not need to be in
305 * sync as they occur in critical sections. But the way flags
306 * is currently used, these changes do not affect the code
307 * except that when a change is made, it may have a slight
308 * delay in propagating the changes to other CPUs due to
309 * caching and such. Which is mostly OK ;-)
312 atomic_t sm_ref
; /* soft-mode reference counter */
315 #define __TRACE_EVENT_FLAGS(name, value) \
316 static int __init trace_init_flags_##name(void) \
318 event_##name.flags = value; \
321 early_initcall(trace_init_flags_##name);
323 #define __TRACE_EVENT_PERF_PERM(name, expr...) \
324 static int perf_perm_##name(struct ftrace_event_call *tp_event, \
325 struct perf_event *p_event) \
327 return ({ expr; }); \
329 static int __init trace_init_perf_perm_##name(void) \
331 event_##name.perf_perm = &perf_perm_##name; \
334 early_initcall(trace_init_perf_perm_##name);
336 #define PERF_MAX_TRACE_SIZE 2048
338 #define MAX_FILTER_STR_VAL 256 /* Should handle KSYM_SYMBOL_LEN */
340 extern void destroy_preds(struct ftrace_event_file
*file
);
341 extern void destroy_call_preds(struct ftrace_event_call
*call
);
342 extern int filter_match_preds(struct event_filter
*filter
, void *rec
);
344 extern int filter_check_discard(struct ftrace_event_file
*file
, void *rec
,
345 struct ring_buffer
*buffer
,
346 struct ring_buffer_event
*event
);
347 extern int call_filter_check_discard(struct ftrace_event_call
*call
, void *rec
,
348 struct ring_buffer
*buffer
,
349 struct ring_buffer_event
*event
);
353 FILTER_STATIC_STRING
,
359 #define EVENT_STORAGE_SIZE 128
360 extern struct mutex event_storage_mutex
;
361 extern char event_storage
[EVENT_STORAGE_SIZE
];
363 extern int trace_event_raw_init(struct ftrace_event_call
*call
);
364 extern int trace_define_field(struct ftrace_event_call
*call
, const char *type
,
365 const char *name
, int offset
, int size
,
366 int is_signed
, int filter_type
);
367 extern int trace_add_event_call(struct ftrace_event_call
*call
);
368 extern int trace_remove_event_call(struct ftrace_event_call
*call
);
370 #define is_signed_type(type) (((type)(-1)) < (type)1)
372 int trace_set_clr_event(const char *system
, const char *event
, int set
);
375 * The double __builtin_constant_p is because gcc will give us an error
376 * if we try to allocate the static variable to fmt if it is not a
377 * constant. Even with the outer if statement optimizing out.
379 #define event_trace_printk(ip, fmt, args...) \
381 __trace_printk_check_format(fmt, ##args); \
382 tracing_record_cmdline(current); \
383 if (__builtin_constant_p(fmt)) { \
384 static const char *trace_printk_fmt \
385 __attribute__((section("__trace_printk_fmt"))) = \
386 __builtin_constant_p(fmt) ? fmt : NULL; \
388 __trace_bprintk(ip, trace_printk_fmt, ##args); \
390 __trace_printk(ip, fmt, ##args); \
394 * tracepoint_string - register constant persistent string to trace system
395 * @str - a constant persistent string that will be referenced in tracepoints
397 * If constant strings are being used in tracepoints, it is faster and
398 * more efficient to just save the pointer to the string and reference
399 * that with a printf "%s" instead of saving the string in the ring buffer
400 * and wasting space and time.
402 * The problem with the above approach is that userspace tools that read
403 * the binary output of the trace buffers do not have access to the string.
404 * Instead they just show the address of the string which is not very
407 * With tracepoint_string(), the string will be registered to the tracing
408 * system and exported to userspace via the debugfs/tracing/printk_formats
409 * file that maps the string address to the string text. This way userspace
410 * tools that read the binary buffers have a way to map the pointers to
411 * the ASCII strings they represent.
413 * The @str used must be a constant string and persistent as it would not
414 * make sense to show a string that no longer exists. But it is still fine
415 * to be used with modules, because when modules are unloaded, if they
416 * had tracepoints, the ring buffers are cleared too. As long as the string
417 * does not change during the life of the module, it is fine to use
418 * tracepoint_string() within a module.
420 #define tracepoint_string(str) \
422 static const char *___tp_str __tracepoint_string = str; \
425 #define __tracepoint_string __attribute__((section("__tracepoint_str")))
427 #ifdef CONFIG_PERF_EVENTS
430 DECLARE_PER_CPU(struct pt_regs
, perf_trace_regs
);
432 extern int perf_trace_init(struct perf_event
*event
);
433 extern void perf_trace_destroy(struct perf_event
*event
);
434 extern int perf_trace_add(struct perf_event
*event
, int flags
);
435 extern void perf_trace_del(struct perf_event
*event
, int flags
);
436 extern int ftrace_profile_set_filter(struct perf_event
*event
, int event_id
,
438 extern void ftrace_profile_free_filter(struct perf_event
*event
);
439 extern void *perf_trace_buf_prepare(int size
, unsigned short type
,
440 struct pt_regs
*regs
, int *rctxp
);
443 perf_trace_buf_submit(void *raw_data
, int size
, int rctx
, u64 addr
,
444 u64 count
, struct pt_regs
*regs
, void *head
,
445 struct task_struct
*task
)
447 perf_tp_event(addr
, count
, raw_data
, size
, regs
, head
, rctx
, task
);
451 #endif /* _LINUX_FTRACE_EVENT_H */