Linux Perf
trigger.h
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1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __TRIGGER_H_
3 #define __TRIGGER_H_ 1
4 
5 #include "util/debug.h"
6 #include "asm/bug.h"
7 
8 /*
9  * Use trigger to model operations which need to be executed when
10  * an event (a signal, for example) is observed.
11  *
12  * States and transits:
13  *
14  *
15  * OFF--> ON --> READY --(hit)--> HIT
16  * ^ |
17  * | (ready)
18  * | |
19  * \_____________/
20  *
21  * is_hit and is_ready are two key functions to query the state of
22  * a trigger. is_hit means the event already happen; is_ready means the
23  * trigger is waiting for the event.
24  */
25 
26 struct trigger {
27  volatile enum {
33  } state;
34  const char *name;
35 };
36 
37 #define TRIGGER_WARN_ONCE(t, exp) \
38  WARN_ONCE(t->state != exp, "trigger '%s' state transist error: %d in %s()\n", \
39  t->name, t->state, __func__)
40 
41 static inline bool trigger_is_available(struct trigger *t)
42 {
43  return t->state >= 0;
44 }
45 
46 static inline bool trigger_is_error(struct trigger *t)
47 {
48  return t->state <= TRIGGER_ERROR;
49 }
50 
51 static inline void trigger_on(struct trigger *t)
52 {
54  t->state = TRIGGER_ON;
55 }
56 
57 static inline void trigger_ready(struct trigger *t)
58 {
59  if (!trigger_is_available(t))
60  return;
61  t->state = TRIGGER_READY;
62 }
63 
64 static inline void trigger_hit(struct trigger *t)
65 {
66  if (!trigger_is_available(t))
67  return;
69  t->state = TRIGGER_HIT;
70 }
71 
72 static inline void trigger_off(struct trigger *t)
73 {
74  if (!trigger_is_available(t))
75  return;
76  t->state = TRIGGER_OFF;
77 }
78 
79 static inline void trigger_error(struct trigger *t)
80 {
81  t->state = TRIGGER_ERROR;
82 }
83 
84 static inline bool trigger_is_ready(struct trigger *t)
85 {
86  return t->state == TRIGGER_READY;
87 }
88 
89 static inline bool trigger_is_hit(struct trigger *t)
90 {
91  return t->state == TRIGGER_HIT;
92 }
93 
94 #define DEFINE_TRIGGER(n) \
95 struct trigger n = {.state = TRIGGER_OFF, .name = #n}
96 #endif
static void trigger_on(struct trigger *t)
Definition: trigger.h:51
static void trigger_ready(struct trigger *t)
Definition: trigger.h:57
static void trigger_hit(struct trigger *t)
Definition: trigger.h:64
const char * name
Definition: trigger.h:34
enum trigger::@156 state
static bool trigger_is_error(struct trigger *t)
Definition: trigger.h:46
static bool trigger_is_available(struct trigger *t)
Definition: trigger.h:41
static bool trigger_is_hit(struct trigger *t)
Definition: trigger.h:89
static void trigger_error(struct trigger *t)
Definition: trigger.h:79
#define TRIGGER_WARN_ONCE(t, exp)
Definition: trigger.h:37
static void trigger_off(struct trigger *t)
Definition: trigger.h:72
static bool trigger_is_ready(struct trigger *t)
Definition: trigger.h:84