xref: /llvm-project/compiler-rt/test/tsan/Linux/fork_multithreaded4.cpp (revision a68b52e0a33382f241a250c1d67bed1141727447)
1 // RUN: %clangxx_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
2 
3 // The test tries to provoke internal allocator to be locked during fork
4 // and then force the child process to use the internal allocator.
5 
6 #include "../test.h"
7 #include <errno.h>
8 #include <sys/types.h>
9 #include <sys/wait.h>
10 
forker(void * arg)11 static void *forker(void *arg) {
12   void *p = calloc(1, 16);
13   static_cast<volatile int *>(p)[0]++;
14   __atomic_fetch_add(static_cast<int *>(p), 1, __ATOMIC_SEQ_CST);
15   int pid = fork();
16   if (pid < 0) {
17     fprintf(stderr, "failed to fork (%d)\n", errno);
18     exit(1);
19   }
20   if (pid == 0) {
21     __atomic_fetch_add(&static_cast<int *>(p)[1], 1, __ATOMIC_SEQ_CST);
22     exit(0);
23   }
24   int status = 0;
25   while (waitpid(pid, &status, 0) != pid) {
26   }
27   if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
28     fprintf(stderr, "subprocess failed (%d)\n", status);
29     exit(1);
30   }
31   free(p);
32   return 0;
33 }
34 
main()35 int main() {
36   for (int i = 0; i < 10; i++) {
37     pthread_t threads[100];
38     for (auto &th : threads)
39       pthread_create(&th, 0, forker, 0);
40     for (auto th : threads)
41       pthread_join(th, 0);
42   }
43   fprintf(stderr, "DONE\n");
44 }
45 
46 // CHECK: DONE
47