sysdeps/pthread/tst-create1.c

   1 /* Verify that pthread_create does not deadlock when ctors take locks.
   2    Copyright (C) 2021-2024 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <stdio.h>
  20 #include <support/xdlfcn.h>
  21 #include <support/xthread.h>
  22
  23 /*
  24 Check if ctor and pthread_create deadlocks in
  25
  26 thread 1: dlopen -> ctor -> lock(user_lock)
  27 thread 2: lock(user_lock) -> pthread_create
  28
  29 or in
  30
  31 thread 1: dlclose -> dtor -> lock(user_lock)
  32 thread 2: lock(user_lock) -> pthread_create
  33 */
  34
  35 static pthread_barrier_t bar_ctor;
  36 static pthread_barrier_t bar_ctor_finish;
  37 static pthread_barrier_t bar_dtor;
  38 static pthread_mutex_t user_lock = PTHREAD_MUTEX_INITIALIZER;
  39
  40 void
  41 ctor (void)
  42 {
  43   xpthread_barrier_wait (&bar_ctor);
  44   dprintf (1, "thread 1: in ctor: started.\n");
  45   xpthread_mutex_lock (&user_lock);
  46   dprintf (1, "thread 1: in ctor: locked user_lock.\n");
  47   xpthread_mutex_unlock (&user_lock);
  48   dprintf (1, "thread 1: in ctor: unlocked user_lock.\n");
  49   dprintf (1, "thread 1: in ctor: done.\n");
  50   xpthread_barrier_wait (&bar_ctor_finish);
  51 }
  52
  53 void
  54 dtor (void)
  55 {
  56   xpthread_barrier_wait (&bar_dtor);
  57   dprintf (1, "thread 1: in dtor: started.\n");
  58   xpthread_mutex_lock (&user_lock);
  59   dprintf (1, "thread 1: in dtor: locked user_lock.\n");
  60   xpthread_mutex_unlock (&user_lock);
  61   dprintf (1, "thread 1: in dtor: unlocked user_lock.\n");
  62   dprintf (1, "thread 1: in dtor: done.\n");
  63 }
  64
  65 static void *
  66 thread3 (void *a)
  67 {
  68   dprintf (1, "thread 3: started.\n");
  69   dprintf (1, "thread 3: done.\n");
  70   return 0;
  71 }
  72
  73 static void *
  74 thread2 (void *a)
  75 {
  76   pthread_t t3;
  77   dprintf (1, "thread 2: started.\n");
  78
  79   xpthread_mutex_lock (&user_lock);
  80   dprintf (1, "thread 2: locked user_lock.\n");
  81   xpthread_barrier_wait (&bar_ctor);
  82   t3 = xpthread_create (0, thread3, 0);
  83   xpthread_mutex_unlock (&user_lock);
  84   dprintf (1, "thread 2: unlocked user_lock.\n");
  85   xpthread_join (t3);
  86   xpthread_barrier_wait (&bar_ctor_finish);
  87
  88   xpthread_mutex_lock (&user_lock);
  89   dprintf (1, "thread 2: locked user_lock.\n");
  90   xpthread_barrier_wait (&bar_dtor);
  91   t3 = xpthread_create (0, thread3, 0);
  92   xpthread_mutex_unlock (&user_lock);
  93   dprintf (1, "thread 2: unlocked user_lock.\n");
  94   xpthread_join (t3);
  95
  96   dprintf (1, "thread 2: done.\n");
  97   return 0;
  98 }
  99
 100 static void
 101 thread1 (void)
 102 {
 103   dprintf (1, "thread 1: started.\n");
 104   xpthread_barrier_init (&bar_ctor, NULL, 2);
 105   xpthread_barrier_init (&bar_ctor_finish, NULL, 2);
 106   xpthread_barrier_init (&bar_dtor, NULL, 2);
 107   pthread_t t2 = xpthread_create (0, thread2, 0);
 108   void *p = xdlopen ("tst-create1mod.so", RTLD_NOW | RTLD_GLOBAL);
 109   dprintf (1, "thread 1: dlopen done.\n");
 110   xdlclose (p);
 111   dprintf (1, "thread 1: dlclose done.\n");
 112   xpthread_join (t2);
 113   dprintf (1, "thread 1: done.\n");
 114 }
 115
 116 static int
 117 do_test (void)
 118 {
 119   thread1 ();
 120   return 0;
 121 }
 122
 123 #include <support/test-driver.c>