1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2016 Google, Inc.
4 */
5
6 #define _GNU_SOURCE
7
8 #include <errno.h>
9 #include <fcntl.h>
10 #include <sched.h>
11 #include <signal.h>
12 #include <stdbool.h>
13 #include <stdio.h>
14 #include <string.h>
15 #include <unistd.h>
16 #include <sys/ptrace.h>
17 #include <sys/stat.h>
18 #include <sys/timerfd.h>
19 #include <sys/types.h>
20 #include <sys/wait.h>
21
22 #include "../kselftest.h"
23
child(int cpu)24 void child(int cpu)
25 {
26 cpu_set_t set;
27
28 CPU_ZERO(&set);
29 CPU_SET(cpu, &set);
30 if (sched_setaffinity(0, sizeof(set), &set) != 0) {
31 ksft_print_msg("sched_setaffinity() failed: %s\n",
32 strerror(errno));
33 _exit(1);
34 }
35
36 if (ptrace(PTRACE_TRACEME, 0, NULL, NULL) != 0) {
37 ksft_print_msg("ptrace(PTRACE_TRACEME) failed: %s\n",
38 strerror(errno));
39 _exit(1);
40 }
41
42 if (raise(SIGSTOP) != 0) {
43 ksft_print_msg("raise(SIGSTOP) failed: %s\n", strerror(errno));
44 _exit(1);
45 }
46
47 _exit(0);
48 }
49
run_test(int cpu)50 int run_test(int cpu)
51 {
52 int status;
53 pid_t pid = fork();
54 pid_t wpid;
55
56 if (pid < 0) {
57 ksft_print_msg("fork() failed: %s\n", strerror(errno));
58 return KSFT_FAIL;
59 }
60 if (pid == 0)
61 child(cpu);
62
63 wpid = waitpid(pid, &status, __WALL);
64 if (wpid != pid) {
65 ksft_print_msg("waitpid() failed: %s\n", strerror(errno));
66 return KSFT_FAIL;
67 }
68 if (!WIFSTOPPED(status)) {
69 ksft_print_msg("child did not stop: %s\n", strerror(errno));
70 return KSFT_FAIL;
71 }
72 if (WSTOPSIG(status) != SIGSTOP) {
73 ksft_print_msg("child did not stop with SIGSTOP: %s\n",
74 strerror(errno));
75 return KSFT_FAIL;
76 }
77
78 if (ptrace(PTRACE_SINGLESTEP, pid, NULL, NULL) < 0) {
79 if (errno == EIO) {
80 ksft_print_msg(
81 "ptrace(PTRACE_SINGLESTEP) not supported on this architecture: %s\n",
82 strerror(errno));
83 return KSFT_SKIP;
84 }
85 ksft_print_msg("ptrace(PTRACE_SINGLESTEP) failed: %s\n",
86 strerror(errno));
87 return KSFT_FAIL;
88 }
89
90 wpid = waitpid(pid, &status, __WALL);
91 if (wpid != pid) {
92 ksft_print_msg("waitpid() failed: %s\n", strerror(errno));
93 return KSFT_FAIL;
94 }
95 if (WIFEXITED(status)) {
96 ksft_print_msg("child did not single-step: %s\n",
97 strerror(errno));
98 return KSFT_FAIL;
99 }
100 if (!WIFSTOPPED(status)) {
101 ksft_print_msg("child did not stop: %s\n", strerror(errno));
102 return KSFT_FAIL;
103 }
104 if (WSTOPSIG(status) != SIGTRAP) {
105 ksft_print_msg("child did not stop with SIGTRAP: %s\n",
106 strerror(errno));
107 return KSFT_FAIL;
108 }
109
110 if (ptrace(PTRACE_CONT, pid, NULL, NULL) < 0) {
111 ksft_print_msg("ptrace(PTRACE_CONT) failed: %s\n",
112 strerror(errno));
113 return KSFT_FAIL;
114 }
115
116 wpid = waitpid(pid, &status, __WALL);
117 if (wpid != pid) {
118 ksft_print_msg("waitpid() failed: %s\n", strerror(errno));
119 return KSFT_FAIL;
120 }
121 if (!WIFEXITED(status)) {
122 ksft_print_msg("child did not exit after PTRACE_CONT: %s\n",
123 strerror(errno));
124 return KSFT_FAIL;
125 }
126
127 return KSFT_PASS;
128 }
129
suspend(void)130 void suspend(void)
131 {
132 int power_state_fd;
133 int timerfd;
134 int err;
135 struct itimerspec spec = {};
136
137 if (getuid() != 0)
138 ksft_exit_skip("Please run the test as root - Exiting.\n");
139
140 power_state_fd = open("/sys/power/state", O_RDWR);
141 if (power_state_fd < 0)
142 ksft_exit_fail_msg(
143 "open(\"/sys/power/state\") failed %s)\n",
144 strerror(errno));
145
146 timerfd = timerfd_create(CLOCK_BOOTTIME_ALARM, 0);
147 if (timerfd < 0)
148 ksft_exit_fail_msg("timerfd_create() failed\n");
149
150 spec.it_value.tv_sec = 5;
151 err = timerfd_settime(timerfd, 0, &spec, NULL);
152 if (err < 0)
153 ksft_exit_fail_msg("timerfd_settime() failed\n");
154
155 system("(echo mem > /sys/power/state) 2> /dev/null");
156
157 timerfd_gettime(timerfd, &spec);
158 if (spec.it_value.tv_sec != 0 || spec.it_value.tv_nsec != 0)
159 ksft_exit_fail_msg("Failed to enter Suspend state\n");
160
161 close(timerfd);
162 close(power_state_fd);
163 }
164
main(int argc,char ** argv)165 int main(int argc, char **argv)
166 {
167 int opt;
168 bool do_suspend = true;
169 bool succeeded = true;
170 unsigned int tests = 0;
171 cpu_set_t available_cpus;
172 int err;
173 int cpu;
174
175 ksft_print_header();
176
177 while ((opt = getopt(argc, argv, "n")) != -1) {
178 switch (opt) {
179 case 'n':
180 do_suspend = false;
181 break;
182 default:
183 printf("Usage: %s [-n]\n", argv[0]);
184 printf(" -n: do not trigger a suspend/resume cycle before the test\n");
185 return -1;
186 }
187 }
188
189 err = sched_getaffinity(0, sizeof(available_cpus), &available_cpus);
190 if (err < 0)
191 ksft_exit_fail_msg("sched_getaffinity() failed\n");
192
193 for (cpu = 0; cpu < CPU_SETSIZE; cpu++) {
194 if (!CPU_ISSET(cpu, &available_cpus))
195 continue;
196 tests++;
197 }
198
199 if (do_suspend)
200 suspend();
201
202 ksft_set_plan(tests);
203 for (cpu = 0; cpu < CPU_SETSIZE; cpu++) {
204 int test_success;
205
206 if (!CPU_ISSET(cpu, &available_cpus))
207 continue;
208
209 test_success = run_test(cpu);
210 switch (test_success) {
211 case KSFT_PASS:
212 ksft_test_result_pass("CPU %d\n", cpu);
213 break;
214 case KSFT_SKIP:
215 ksft_test_result_skip("CPU %d\n", cpu);
216 break;
217 case KSFT_FAIL:
218 ksft_test_result_fail("CPU %d\n", cpu);
219 succeeded = false;
220 break;
221 }
222 }
223
224 if (succeeded)
225 ksft_exit_pass();
226 else
227 ksft_exit_fail();
228 }
229