1  /* pthread_spin_unlock -- unlock a spin lock.  Generic version.
       2     Copyright (C) 2003-2023 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 "pthreadP.h"
      20  #include <atomic.h>
      21  #include <shlib-compat.h>
      22  
      23  int
      24  __pthread_spin_unlock (pthread_spinlock_t *lock)
      25  {
      26    /* The atomic_store_release synchronizes-with the atomic_exchange_acquire
      27       or atomic_compare_exchange_weak_acquire in pthread_spin_lock /
      28       pthread_spin_trylock.  */
      29    atomic_store_release (lock, 0);
      30    return 0;
      31  }
      32  versioned_symbol (libc, __pthread_spin_unlock, pthread_spin_unlock,
      33                    GLIBC_2_34);
      34  
      35  #if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_2, GLIBC_2_34)
      36  compat_symbol (libpthread, __pthread_spin_unlock, pthread_spin_unlock,
      37                 GLIBC_2_2);
      38  #endif