xref: /linux/samples/trace_events/trace_custom_sched.h (revision da1d9caf95def6f0320819cf941c9fd1069ba9e1)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 
3 /*
4  * Like the headers that use TRACE_EVENT(), the TRACE_CUSTOM_EVENT()
5  * needs a header that allows for multiple inclusions.
6  *
7  * Test for a unique name (here we have _TRACE_CUSTOM_SCHED_H),
8  * also allowing to continue if TRACE_CUSTOM_MULTI_READ is defined.
9  */
10 #if !defined(_TRACE_CUSTOM_SCHED_H) || defined(TRACE_CUSTOM_MULTI_READ)
11 #define _TRACE_CUSTOM_SCHED_H
12 
13 /* Include linux/trace_events.h for initial defines of TRACE_CUSTOM_EVENT() */
14 #include <linux/trace_events.h>
15 
16 /*
17  * TRACE_CUSTOM_EVENT() is just like TRACE_EVENT(). The first parameter
18  * is the event name of an existing event where the TRACE_EVENT has been included
19  * in the C file before including this file.
20  */
21 TRACE_CUSTOM_EVENT(sched_switch,
22 
23 	/*
24 	 * The TP_PROTO() and TP_ARGS must match the trace event
25 	 * that the custom event is using.
26 	 */
27 	TP_PROTO(bool preempt,
28 		 struct task_struct *prev,
29 		 struct task_struct *next,
30 		 unsigned int prev_state),
31 
32 	TP_ARGS(preempt, prev, next, prev_state),
33 
34 	/*
35 	 * The next fields are where the customization happens.
36 	 * The TP_STRUCT__entry() defines what will be recorded
37 	 * in the ring buffer when the custom event triggers.
38 	 *
39 	 * The rest is just like the TRACE_EVENT() macro except that
40 	 * it uses the custom entry.
41 	 */
42 	TP_STRUCT__entry(
43 		__field(	unsigned short,		prev_prio	)
44 		__field(	unsigned short,		next_prio	)
45 		__field(	pid_t,	next_pid			)
46 	),
47 
48 	TP_fast_assign(
49 		__entry->prev_prio	= prev->prio;
50 		__entry->next_pid	= next->pid;
51 		__entry->next_prio	= next->prio;
52 	),
53 
54 	TP_printk("prev_prio=%d next_pid=%d next_prio=%d",
55 		  __entry->prev_prio, __entry->next_pid, __entry->next_prio)
56 )
57 
58 
59 TRACE_CUSTOM_EVENT(sched_waking,
60 
61 	TP_PROTO(struct task_struct *p),
62 
63 	TP_ARGS(p),
64 
65 	TP_STRUCT__entry(
66 		__field(	pid_t,			pid	)
67 		__field(	unsigned short,		prio	)
68 	),
69 
70 	TP_fast_assign(
71 		__entry->pid	= p->pid;
72 		__entry->prio	= p->prio;
73 	),
74 
75 	TP_printk("pid=%d prio=%d", __entry->pid, __entry->prio)
76 )
77 #endif
78 /*
79  * Just like the headers that create TRACE_EVENTs, the below must
80  * be outside the protection of the above #if block.
81  */
82 
83 /*
84  * It is required that the Makefile includes:
85  *    CFLAGS_<c_file>.o := -I$(src)
86  */
87 #undef TRACE_INCLUDE_PATH
88 #undef TRACE_INCLUDE_FILE
89 #define TRACE_INCLUDE_PATH .
90 
91 /*
92  * It is requred that the TRACE_INCLUDE_FILE be the same
93  * as this file without the ".h".
94  */
95 #define TRACE_INCLUDE_FILE trace_custom_sched
96 #include <trace/define_custom_trace.h>
97