tools/testing/selftests/breakpoints/step_after_suspend_test.c

   1 /*
   2  * Copyright (C) 2016 Google, Inc.
   3  *
   4  * This software is licensed under the terms of the GNU General Public
   5  * License version 2, as published by the Free Software Foundation, and
   6  * may be copied, distributed, and modified under those terms.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  */
  14
  15 #define _GNU_SOURCE
  16
  17 #include <errno.h>
  18 #include <fcntl.h>
  19 #include <sched.h>
  20 #include <signal.h>
  21 #include <stdbool.h>
  22 #include <stdio.h>
  23 #include <string.h>
  24 #include <unistd.h>
  25 #include <sys/ptrace.h>
  26 #include <sys/stat.h>
  27 #include <sys/timerfd.h>
  28 #include <sys/types.h>
  29 #include <sys/wait.h>
  30
  31 #include "../kselftest.h"
  32
  33 void child(int cpu)
  34 {
  35         cpu_set_t set;
  36
  37         CPU_ZERO(&set);
  38         CPU_SET(cpu, &set);
  39         if (sched_setaffinity(0, sizeof(set), &set) != 0) {
  40                 ksft_print_msg("sched_setaffinity() failed: %s\n",
  41                         strerror(errno));
  42                 _exit(1);
  43         }
  44
  45         if (ptrace(PTRACE_TRACEME, 0, NULL, NULL) != 0) {
  46                 ksft_print_msg("ptrace(PTRACE_TRACEME) failed: %s\n",
  47                         strerror(errno));
  48                 _exit(1);
  49         }
  50
  51         if (raise(SIGSTOP) != 0) {
  52                 ksft_print_msg("raise(SIGSTOP) failed: %s\n", strerror(errno));
  53                 _exit(1);
  54         }
  55
  56         _exit(0);
  57 }
  58
  59 bool run_test(int cpu)
  60 {
  61         int status;
  62         pid_t pid = fork();
  63         pid_t wpid;
  64
  65         if (pid < 0) {
  66                 ksft_print_msg("fork() failed: %s\n", strerror(errno));
  67                 return false;
  68         }
  69         if (pid == 0)
  70                 child(cpu);
  71
  72         wpid = waitpid(pid, &status, __WALL);
  73         if (wpid != pid) {
  74                 ksft_print_msg("waitpid() failed: %s\n", strerror(errno));
  75                 return false;
  76         }
  77         if (!WIFSTOPPED(status)) {
  78                 ksft_print_msg("child did not stop: %s\n", strerror(errno));
  79                 return false;
  80         }
  81         if (WSTOPSIG(status) != SIGSTOP) {
  82                 ksft_print_msg("child did not stop with SIGSTOP: %s\n",
  83                         strerror(errno));
  84                 return false;
  85         }
  86
  87         if (ptrace(PTRACE_SINGLESTEP, pid, NULL, NULL) < 0) {
  88                 if (errno == EIO) {
  89                         ksft_exit_skip(
  90                                 "ptrace(PTRACE_SINGLESTEP) not supported on this architecture: %s\n",
  91                                 strerror(errno));
  92                 }
  93                 ksft_print_msg("ptrace(PTRACE_SINGLESTEP) failed: %s\n",
  94                         strerror(errno));
  95                 return false;
  96         }
  97
  98         wpid = waitpid(pid, &status, __WALL);
  99         if (wpid != pid) {
 100                 ksft_print_msg("waitpid() failed: $s\n", strerror(errno));
 101                 return false;
 102         }
 103         if (WIFEXITED(status)) {
 104                 ksft_print_msg("child did not single-step: %s\n",
 105                         strerror(errno));
 106                 return false;
 107         }
 108         if (!WIFSTOPPED(status)) {
 109                 ksft_print_msg("child did not stop: %s\n", strerror(errno));
 110                 return false;
 111         }
 112         if (WSTOPSIG(status) != SIGTRAP) {
 113                 ksft_print_msg("child did not stop with SIGTRAP: %s\n",
 114                         strerror(errno));
 115                 return false;
 116         }
 117
 118         if (ptrace(PTRACE_CONT, pid, NULL, NULL) < 0) {
 119                 ksft_print_msg("ptrace(PTRACE_CONT) failed: %s\n",
 120                         strerror(errno));
 121                 return false;
 122         }
 123
 124         wpid = waitpid(pid, &status, __WALL);
 125         if (wpid != pid) {
 126                 ksft_print_msg("waitpid() failed: %s\n", strerror(errno));
 127                 return false;
 128         }
 129         if (!WIFEXITED(status)) {
 130                 ksft_print_msg("child did not exit after PTRACE_CONT: %s\n",
 131                         strerror(errno));
 132                 return false;
 133         }
 134
 135         return true;
 136 }
 137
 138 void suspend(void)
 139 {
 140         int power_state_fd;
 141         struct sigevent event = {};
 142         int timerfd;
 143         int err;
 144         struct itimerspec spec = {};
 145
 146         if (getuid() != 0)
 147                 ksft_exit_skip("Please run the test as root - Exiting.\n");
 148
 149         power_state_fd = open("/sys/power/state", O_RDWR);
 150         if (power_state_fd < 0)
 151                 ksft_exit_fail_msg(
 152                         "open(\"/sys/power/state\") failed %s)\n",
 153                         strerror(errno));
 154
 155         timerfd = timerfd_create(CLOCK_BOOTTIME_ALARM, 0);
 156         if (timerfd < 0)
 157                 ksft_exit_fail_msg("timerfd_create() failed\n");
 158
 159         spec.it_value.tv_sec = 5;
 160         err = timerfd_settime(timerfd, 0, &spec, NULL);
 161         if (err < 0)
 162                 ksft_exit_fail_msg("timerfd_settime() failed\n");
 163
 164         if (write(power_state_fd, "mem", strlen("mem")) != strlen("mem"))
 165                 ksft_exit_fail_msg("Failed to enter Suspend state\n");
 166
 167         close(timerfd);
 168         close(power_state_fd);
 169 }
 170
 171 int main(int argc, char **argv)
 172 {
 173         int opt;
 174         bool do_suspend = true;
 175         bool succeeded = true;
 176         cpu_set_t available_cpus;
 177         int err;
 178         int cpu;
 179
 180         ksft_print_header();
 181
 182         while ((opt = getopt(argc, argv, "n")) != -1) {
 183                 switch (opt) {
 184                 case 'n':
 185                         do_suspend = false;
 186                         break;
 187                 default:
 188                         printf("Usage: %s [-n]\n", argv[0]);
 189                         printf("        -n: do not trigger a suspend/resume cycle before the test\n");
 190                         return -1;
 191                 }
 192         }
 193
 194         if (do_suspend)
 195                 suspend();
 196
 197         err = sched_getaffinity(0, sizeof(available_cpus), &available_cpus);
 198         if (err < 0)
 199                 ksft_exit_fail_msg("sched_getaffinity() failed\n");
 200
 201         for (cpu = 0; cpu < CPU_SETSIZE; cpu++) {
 202                 bool test_success;
 203
 204                 if (!CPU_ISSET(cpu, &available_cpus))
 205                         continue;
 206
 207                 test_success = run_test(cpu);
 208                 if (test_success) {
 209                         ksft_test_result_pass("CPU %d\n", cpu);
 210                 } else {
 211                         ksft_test_result_fail("CPU %d\n", cpu);
 212                         succeeded = false;
 213                 }
 214         }
 215
 216         if (succeeded)
 217                 ksft_exit_pass();
 218         else
 219                 ksft_exit_fail();
 220 }