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
24void 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
50int 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
130void suspend(void)
131{
132	int power_state_fd;
133	struct sigevent event = {};
134	int timerfd;
135	int err;
136	struct itimerspec spec = {};
137
138	if (getuid() != 0)
139		ksft_exit_skip("Please run the test as root - Exiting.\n");
140
141	power_state_fd = open("/sys/power/state", O_RDWR);
142	if (power_state_fd < 0)
143		ksft_exit_fail_msg(
144			"open(\"/sys/power/state\") failed %s)\n",
145			strerror(errno));
146
147	timerfd = timerfd_create(CLOCK_BOOTTIME_ALARM, 0);
148	if (timerfd < 0)
149		ksft_exit_fail_msg("timerfd_create() failed\n");
150
151	spec.it_value.tv_sec = 5;
152	err = timerfd_settime(timerfd, 0, &spec, NULL);
153	if (err < 0)
154		ksft_exit_fail_msg("timerfd_settime() failed\n");
155
156	if (write(power_state_fd, "mem", strlen("mem")) != strlen("mem"))
157		ksft_exit_fail_msg("Failed to enter Suspend state\n");
158
159	close(timerfd);
160	close(power_state_fd);
161}
162
163int main(int argc, char **argv)
164{
165	int opt;
166	bool do_suspend = true;
167	bool succeeded = true;
168	unsigned int tests = 0;
169	cpu_set_t available_cpus;
170	int err;
171	int cpu;
172
173	ksft_print_header();
174
175	while ((opt = getopt(argc, argv, "n")) != -1) {
176		switch (opt) {
177		case 'n':
178			do_suspend = false;
179			break;
180		default:
181			printf("Usage: %s [-n]\n", argv[0]);
182			printf("        -n: do not trigger a suspend/resume cycle before the test\n");
183			return -1;
184		}
185	}
186
187	err = sched_getaffinity(0, sizeof(available_cpus), &available_cpus);
188	if (err < 0)
189		ksft_exit_fail_msg("sched_getaffinity() failed\n");
190
191	for (cpu = 0; cpu < CPU_SETSIZE; cpu++) {
192		if (!CPU_ISSET(cpu, &available_cpus))
193			continue;
194		tests++;
195	}
196
197	if (do_suspend)
198		suspend();
199
200	ksft_set_plan(tests);
201	for (cpu = 0; cpu < CPU_SETSIZE; cpu++) {
202		int test_success;
203
204		if (!CPU_ISSET(cpu, &available_cpus))
205			continue;
206
207		test_success = run_test(cpu);
208		switch (test_success) {
209		case KSFT_PASS:
210			ksft_test_result_pass("CPU %d\n", cpu);
211			break;
212		case KSFT_SKIP:
213			ksft_test_result_skip("CPU %d\n", cpu);
214			break;
215		case KSFT_FAIL:
216			ksft_test_result_fail("CPU %d\n", cpu);
217			succeeded = false;
218			break;
219		}
220	}
221
222	if (succeeded)
223		ksft_exit_pass();
224	else
225		ksft_exit_fail();
226}
227