1// SPDX-License-Identifier: GPL-2.0
2/*
3 * User Events Perf Events Test Program
4 *
5 * Copyright (c) 2021 Beau Belgrave <beaub@linux.microsoft.com>
6 */
7
8#include <errno.h>
9#include <linux/user_events.h>
10#include <linux/perf_event.h>
11#include <stdio.h>
12#include <stdlib.h>
13#include <fcntl.h>
14#include <sys/ioctl.h>
15#include <sys/stat.h>
16#include <unistd.h>
17#include <asm/unistd.h>
18
19#include "../kselftest_harness.h"
20#include "user_events_selftests.h"
21
22const char *data_file = "/sys/kernel/tracing/user_events_data";
23const char *id_file = "/sys/kernel/tracing/events/user_events/__test_event/id";
24const char *fmt_file = "/sys/kernel/tracing/events/user_events/__test_event/format";
25
26struct event {
27 __u32 index;
28 __u32 field1;
29 __u32 field2;
30};
31
32static long perf_event_open(struct perf_event_attr *pe, pid_t pid,
33 int cpu, int group_fd, unsigned long flags)
34{
35 return syscall(__NR_perf_event_open, pe, pid, cpu, group_fd, flags);
36}
37
38static int get_id(void)
39{
40 FILE *fp = fopen(id_file, "r");
41 int ret, id = 0;
42
43 if (!fp)
44 return -1;
45
46 ret = fscanf(fp, "%d", &id);
47 fclose(fp);
48
49 if (ret != 1)
50 return -1;
51
52 return id;
53}
54
55static int get_offset(void)
56{
57 FILE *fp = fopen(fmt_file, "r");
58 int ret, c, last = 0, offset = 0;
59
60 if (!fp)
61 return -1;
62
63 /* Read until empty line */
64 while (true) {
65 c = getc(fp);
66
67 if (c == EOF)
68 break;
69
70 if (last == '\n' && c == '\n')
71 break;
72
73 last = c;
74 }
75
76 ret = fscanf(fp, "\tfield:u32 field1;\toffset:%d;", &offset);
77 fclose(fp);
78
79 if (ret != 1)
80 return -1;
81
82 return offset;
83}
84
85static int clear(int *check)
86{
87 struct user_unreg unreg = {0};
88
89 unreg.size = sizeof(unreg);
90 unreg.disable_bit = 31;
91 unreg.disable_addr = (__u64)check;
92
93 int fd = open(data_file, O_RDWR);
94
95 if (fd == -1)
96 return -1;
97
98 if (ioctl(fd, DIAG_IOCSUNREG, &unreg) == -1)
99 if (errno != ENOENT)
100 return -1;
101
102 if (ioctl(fd, DIAG_IOCSDEL, "__test_event") == -1)
103 if (errno != ENOENT)
104 return -1;
105
106 close(fd);
107
108 return 0;
109}
110
111FIXTURE(user) {
112 int data_fd;
113 int check;
114 bool umount;
115};
116
117FIXTURE_SETUP(user) {
118 USER_EVENT_FIXTURE_SETUP(return, self->umount);
119
120 self->data_fd = open(data_file, O_RDWR);
121 ASSERT_NE(-1, self->data_fd);
122}
123
124FIXTURE_TEARDOWN(user) {
125 USER_EVENT_FIXTURE_TEARDOWN(self->umount);
126
127 close(self->data_fd);
128
129 if (clear(check: &self->check) != 0)
130 printf("WARNING: Clear didn't work!\n");
131}
132
133TEST_F(user, perf_write) {
134 struct perf_event_attr pe = {0};
135 struct user_reg reg = {0};
136 struct event event;
137 struct perf_event_mmap_page *perf_page;
138 int page_size = sysconf(_SC_PAGESIZE);
139 int id, fd, offset;
140 __u32 *val;
141
142 reg.size = sizeof(reg);
143 reg.name_args = (__u64)"__test_event u32 field1; u32 field2";
144 reg.enable_bit = 31;
145 reg.enable_addr = (__u64)&self->check;
146 reg.enable_size = sizeof(self->check);
147
148 /* Register should work */
149 ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
150 ASSERT_EQ(0, reg.write_index);
151 ASSERT_EQ(0, self->check);
152
153 /* Id should be there */
154 id = get_id();
155 ASSERT_NE(-1, id);
156 offset = get_offset();
157 ASSERT_NE(-1, offset);
158
159 pe.type = PERF_TYPE_TRACEPOINT;
160 pe.size = sizeof(pe);
161 pe.config = id;
162 pe.sample_type = PERF_SAMPLE_RAW;
163 pe.sample_period = 1;
164 pe.wakeup_events = 1;
165
166 /* Tracepoint attach should work */
167 fd = perf_event_open(pe: &pe, pid: 0, cpu: -1, group_fd: -1, flags: 0);
168 ASSERT_NE(-1, fd);
169
170 perf_page = mmap(NULL, page_size * 2, PROT_READ, MAP_SHARED, fd, 0);
171 ASSERT_NE(MAP_FAILED, perf_page);
172
173 /* Status should be updated */
174 ASSERT_EQ(1 << reg.enable_bit, self->check);
175
176 event.index = reg.write_index;
177 event.field1 = 0xc001;
178 event.field2 = 0xc01a;
179
180 /* Ensure write shows up at correct offset */
181 ASSERT_NE(-1, write(self->data_fd, &event, sizeof(event)));
182 val = (void *)(((char *)perf_page) + perf_page->data_offset);
183 ASSERT_EQ(PERF_RECORD_SAMPLE, *val);
184 /* Skip over header and size, move to offset */
185 val += 3;
186 val = (void *)((char *)val) + offset;
187 /* Ensure correct */
188 ASSERT_EQ(event.field1, *val++);
189 ASSERT_EQ(event.field2, *val++);
190
191 munmap(perf_page, page_size * 2);
192 close(fd);
193
194 /* Status should be updated */
195 ASSERT_EQ(0, self->check);
196}
197
198TEST_F(user, perf_empty_events) {
199 struct perf_event_attr pe = {0};
200 struct user_reg reg = {0};
201 struct perf_event_mmap_page *perf_page;
202 int page_size = sysconf(_SC_PAGESIZE);
203 int id, fd;
204 __u32 *val;
205
206 reg.size = sizeof(reg);
207 reg.name_args = (__u64)"__test_event";
208 reg.enable_bit = 31;
209 reg.enable_addr = (__u64)&self->check;
210 reg.enable_size = sizeof(self->check);
211
212 /* Register should work */
213 ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
214 ASSERT_EQ(0, reg.write_index);
215 ASSERT_EQ(0, self->check);
216
217 /* Id should be there */
218 id = get_id();
219 ASSERT_NE(-1, id);
220
221 pe.type = PERF_TYPE_TRACEPOINT;
222 pe.size = sizeof(pe);
223 pe.config = id;
224 pe.sample_type = PERF_SAMPLE_RAW;
225 pe.sample_period = 1;
226 pe.wakeup_events = 1;
227
228 /* Tracepoint attach should work */
229 fd = perf_event_open(pe: &pe, pid: 0, cpu: -1, group_fd: -1, flags: 0);
230 ASSERT_NE(-1, fd);
231
232 perf_page = mmap(NULL, page_size * 2, PROT_READ, MAP_SHARED, fd, 0);
233 ASSERT_NE(MAP_FAILED, perf_page);
234
235 /* Status should be updated */
236 ASSERT_EQ(1 << reg.enable_bit, self->check);
237
238 /* Ensure write shows up at correct offset */
239 ASSERT_NE(-1, write(self->data_fd, &reg.write_index,
240 sizeof(reg.write_index)));
241 val = (void *)(((char *)perf_page) + perf_page->data_offset);
242 ASSERT_EQ(PERF_RECORD_SAMPLE, *val);
243
244 munmap(perf_page, page_size * 2);
245 close(fd);
246
247 /* Status should be updated */
248 ASSERT_EQ(0, self->check);
249}
250
251int main(int argc, char **argv)
252{
253 return test_harness_run(argc, argv);
254}
255

source code of linux/tools/testing/selftests/user_events/perf_test.c