1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2013, Michael Ellerman, IBM Corp.
4  */
5 
6 #define _GNU_SOURCE
7 #include <unistd.h>
8 #include <sys/syscall.h>
9 #include <string.h>
10 #include <stdio.h>
11 #include <sys/ioctl.h>
12 
13 #include "event.h"
14 
15 
16 int perf_event_open(struct perf_event_attr *attr, pid_t pid, int cpu,
17 		int group_fd, unsigned long flags)
18 {
19 	return syscall(__NR_perf_event_open, attr, pid, cpu,
20 			   group_fd, flags);
21 }
22 
23 void event_init_opts(struct event *e, u64 config, int type, char *name)
24 {
25 	memset(e, 0, sizeof(*e));
26 
27 	e->name = name;
28 
29 	e->attr.type = type;
30 	e->attr.config = config;
31 	e->attr.size = sizeof(e->attr);
32 	/* This has to match the structure layout in the header */
33 	e->attr.read_format = PERF_FORMAT_TOTAL_TIME_ENABLED | \
34 				  PERF_FORMAT_TOTAL_TIME_RUNNING;
35 }
36 
37 void event_init_named(struct event *e, u64 config, char *name)
38 {
39 	event_init_opts(e, config, PERF_TYPE_RAW, name);
40 }
41 
42 void event_init(struct event *e, u64 config)
43 {
44 	event_init_opts(e, config, PERF_TYPE_RAW, "event");
45 }
46 
47 #define PERF_CURRENT_PID	0
48 #define PERF_NO_PID		-1
49 #define PERF_NO_CPU		-1
50 #define PERF_NO_GROUP		-1
51 
52 int event_open_with_options(struct event *e, pid_t pid, int cpu, int group_fd)
53 {
54 	e->fd = perf_event_open(&e->attr, pid, cpu, group_fd, 0);
55 	if (e->fd == -1) {
56 		perror("perf_event_open");
57 		return -1;
58 	}
59 
60 	return 0;
61 }
62 
63 int event_open_with_group(struct event *e, int group_fd)
64 {
65 	return event_open_with_options(e, PERF_CURRENT_PID, PERF_NO_CPU, group_fd);
66 }
67 
68 int event_open_with_pid(struct event *e, pid_t pid)
69 {
70 	return event_open_with_options(e, pid, PERF_NO_CPU, PERF_NO_GROUP);
71 }
72 
73 int event_open_with_cpu(struct event *e, int cpu)
74 {
75 	return event_open_with_options(e, PERF_NO_PID, cpu, PERF_NO_GROUP);
76 }
77 
78 int event_open(struct event *e)
79 {
80 	return event_open_with_options(e, PERF_CURRENT_PID, PERF_NO_CPU, PERF_NO_GROUP);
81 }
82 
83 void event_close(struct event *e)
84 {
85 	close(e->fd);
86 }
87 
88 int event_enable(struct event *e)
89 {
90 	return ioctl(e->fd, PERF_EVENT_IOC_ENABLE);
91 }
92 
93 int event_disable(struct event *e)
94 {
95 	return ioctl(e->fd, PERF_EVENT_IOC_DISABLE);
96 }
97 
98 int event_reset(struct event *e)
99 {
100 	return ioctl(e->fd, PERF_EVENT_IOC_RESET);
101 }
102 
103 int event_read(struct event *e)
104 {
105 	int rc;
106 
107 	rc = read(e->fd, &e->result, sizeof(e->result));
108 	if (rc != sizeof(e->result)) {
109 		fprintf(stderr, "read error on event %p!\n", e);
110 		return -1;
111 	}
112 
113 	return 0;
114 }
115 
116 void event_report_justified(struct event *e, int name_width, int result_width)
117 {
118 	printf("%*s: result %*llu ", name_width, e->name, result_width,
119 	       e->result.value);
120 
121 	if (e->result.running == e->result.enabled)
122 		printf("running/enabled %llu\n", e->result.running);
123 	else
124 		printf("running %llu enabled %llu\n", e->result.running,
125 			e->result.enabled);
126 }
127 
128 void event_report(struct event *e)
129 {
130 	event_report_justified(e, 0, 0);
131 }
132