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