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 <stdbool.h>
12 #include <sys/ioctl.h>
13
14 #include "event.h"
15
16
17 int perf_event_open(struct perf_event_attr *attr, pid_t pid, int cpu,
18 int group_fd, unsigned long flags)
19 {
20 return syscall(__NR_perf_event_open, attr, pid, cpu,
21 group_fd, flags);
22 }
23
24 static void __event_init_opts(struct event *e, u64 config,
25 int type, char *name, bool sampling)
26 {
27 memset(e, 0, sizeof(*e));
28
29 e->name = name;
30
31 e->attr.type = type;
32 e->attr.config = config;
33 e->attr.size = sizeof(e->attr);
34 /* This has to match the structure layout in the header */
35 e->attr.read_format = PERF_FORMAT_TOTAL_TIME_ENABLED | \
36 PERF_FORMAT_TOTAL_TIME_RUNNING;
37 if (sampling) {
38 e->attr.sample_period = 1000;
39 e->attr.sample_type = PERF_SAMPLE_REGS_INTR;
40 e->attr.disabled = 1;
41 }
42 }
43
44 void event_init_opts(struct event *e, u64 config, int type, char *name)
45 {
46 __event_init_opts(e, config, type, name, false);
47 }
48
49 void event_init_named(struct event *e, u64 config, char *name)
50 {
51 event_init_opts(e, config, PERF_TYPE_RAW, name);
52 }
53
54 void event_init(struct event *e, u64 config)
55 {
56 event_init_opts(e, config, PERF_TYPE_RAW, "event");
57 }
58
59 void event_init_sampling(struct event *e, u64 config)
60 {
61 __event_init_opts(e, config, PERF_TYPE_RAW, "event", true);
62 }
63
64 #define PERF_CURRENT_PID 0
65 #define PERF_NO_PID -1
66 #define PERF_NO_CPU -1
67 #define PERF_NO_GROUP -1
68
69 int event_open_with_options(struct event *e, pid_t pid, int cpu, int group_fd)
70 {
71 e->fd = perf_event_open(&e->attr, pid, cpu, group_fd, 0);
72 if (e->fd == -1) {
73 perror("perf_event_open");
74 return -1;
75 }
76
77 return 0;
78 }
79
80 int event_open_with_group(struct event *e, int group_fd)
81 {
82 return event_open_with_options(e, PERF_CURRENT_PID, PERF_NO_CPU, group_fd);
83 }
84
85 int event_open_with_pid(struct event *e, pid_t pid)
86 {
87 return event_open_with_options(e, pid, PERF_NO_CPU, PERF_NO_GROUP);
88 }
89
90 int event_open_with_cpu(struct event *e, int cpu)
91 {
92 return event_open_with_options(e, PERF_NO_PID, cpu, PERF_NO_GROUP);
93 }
94
95 int event_open(struct event *e)
96 {
97 return event_open_with_options(e, PERF_CURRENT_PID, PERF_NO_CPU, PERF_NO_GROUP);
98 }
99
100 void event_close(struct event *e)
101 {
102 close(e->fd);
103 }
104
105 int event_enable(struct event *e)
106 {
107 return ioctl(e->fd, PERF_EVENT_IOC_ENABLE);
108 }
109
110 int event_disable(struct event *e)
111 {
112 return ioctl(e->fd, PERF_EVENT_IOC_DISABLE);
113 }
114
115 int event_reset(struct event *e)
116 {
117 return ioctl(e->fd, PERF_EVENT_IOC_RESET);
118 }
119
120 int event_read(struct event *e)
121 {
122 int rc;
123
124 rc = read(e->fd, &e->result, sizeof(e->result));
125 if (rc != sizeof(e->result)) {
126 fprintf(stderr, "read error on event %p!\n", e);
127 return -1;
128 }
129
130 return 0;
131 }
132
133 void event_report_justified(struct event *e, int name_width, int result_width)
134 {
135 printf("%*s: result %*llu ", name_width, e->name, result_width,
136 e->result.value);
137
138 if (e->result.running == e->result.enabled)
139 printf("running/enabled %llu\n", e->result.running);
140 else
141 printf("running %llu enabled %llu\n", e->result.running,
142 e->result.enabled);
143 }
144
145 void event_report(struct event *e)
146 {
147 event_report_justified(e, 0, 0);
148 }
149
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