tests/test_urcu_fork.c

   1 /*
   2  * test_urcu_fork.c
   3  *
   4  * Userspace RCU library - test program (fork)
   5  *
   6  * Copyright February 2012 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with this program; if not, write to the Free Software Foundation, Inc.,
  20  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21  */
  22
  23 #define _GNU_SOURCE
  24 #include "../config.h"
  25 #include <stdio.h>
  26 #include <pthread.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <sys/types.h>
  30 #include <sys/wait.h>
  31 #include <unistd.h>
  32 #include <stdio.h>
  33 #include <assert.h>
  34 #include <sched.h>
  35 #include <errno.h>
  36
  37 #include <urcu/arch.h>
  38 #include <urcu/tls-compat.h>
  39
  40 #ifndef DYNAMIC_LINK_TEST
  41 #define _LGPL_SOURCE
  42 #else
  43 #define rcu_debug_yield_read()
  44 #endif
  45 #include <urcu.h>
  46
  47 struct test_node {
  48         int somedata;
  49         struct rcu_head head;
  50 };
  51
  52 static void cb(struct rcu_head *head)
  53 {
  54         struct test_node *node;
  55
  56         fprintf(stderr, "rcu callback invoked in pid: %d\n",
  57                 (int) getpid());
  58         node = caa_container_of(head, struct test_node, head);
  59         free(node);
  60 }
  61
  62 static void test_rcu(void)
  63 {
  64         struct test_node *node;
  65
  66         rcu_register_thread();
  67
  68         synchronize_rcu();
  69
  70         rcu_read_lock();
  71         rcu_read_unlock();
  72
  73         node = malloc(sizeof(*node));
  74         assert(node);
  75
  76         call_rcu(&node->head, cb);
  77
  78         synchronize_rcu();
  79
  80         rcu_unregister_thread();
  81 }
  82
  83 int main(int argc, char **argv)
  84 {
  85         pid_t pid;
  86         int ret;
  87
  88 #if 0
  89         /* pthread_atfork does not work with malloc/free in callbacks */
  90         ret = pthread_atfork(call_rcu_before_fork,
  91                 call_rcu_after_fork_parent,
  92                 call_rcu_after_fork_child);
  93         if (ret) {
  94                 errno = ret;
  95                 perror("pthread_atfork");
  96                 exit(EXIT_FAILURE);
  97         }
  98 #endif
  99
 100         test_rcu();
 101
 102         synchronize_rcu();
 103
 104         fprintf(stderr, "%s parent pid: %d, before fork\n",
 105                 argv[0], (int) getpid());
 106
 107         call_rcu_before_fork();
 108         pid = fork();
 109
 110         if (pid == 0) {
 111                 /* child */
 112                 call_rcu_after_fork_child();
 113                 fprintf(stderr, "%s child pid: %d, after fork\n",
 114                         argv[0], (int) getpid());
 115                 test_rcu();
 116                 fprintf(stderr, "%s child pid: %d, after rcu test\n",
 117                         argv[0], (int) getpid());
 118         } else if (pid > 0) {
 119                 int status;
 120
 121                 /* parent */
 122                 call_rcu_after_fork_parent();
 123                 fprintf(stderr, "%s parent pid: %d, after fork\n",
 124                         argv[0], (int) getpid());
 125                 test_rcu();
 126                 fprintf(stderr, "%s parent pid: %d, after rcu test\n",
 127                         argv[0], (int) getpid());
 128                 for (;;) {
 129                         pid = wait(&status);
 130                         if (WIFEXITED(status)) {
 131                                 fprintf(stderr, "child %u exited normally with status %u\n",
 132                                         pid, WEXITSTATUS(status));
 133                                 break;
 134                         } else if (WIFSIGNALED(status)) {
 135                                 fprintf(stderr, "child %u was terminated by signal %u\n",
 136                                         pid, WTERMSIG(status));
 137                                 break;
 138                         } else {
 139                                 continue;
 140                         }
 141                 }
 142         } else {
 143                 perror("fork");
 144                 exit(EXIT_FAILURE);
 145         }
 146         exit(EXIT_SUCCESS);
 147 }