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Diffstat (limited to 'nptl/pthread_cond_destroy.c')
-rw-r--r-- | nptl/pthread_cond_destroy.c | 62 |
1 files changed, 0 insertions, 62 deletions
diff --git a/nptl/pthread_cond_destroy.c b/nptl/pthread_cond_destroy.c deleted file mode 100644 index fc65dca78c..0000000000 --- a/nptl/pthread_cond_destroy.c +++ /dev/null @@ -1,62 +0,0 @@ -/* Copyright (C) 2002-2017 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Ulrich Drepper <drepper@redhat.com>, 2002. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - <http://www.gnu.org/licenses/>. */ - -#include <errno.h> -#include <shlib-compat.h> -#include "pthreadP.h" -#include <stap-probe.h> -#include <atomic.h> -#include <futex-internal.h> - -#include "pthread_cond_common.c" - -/* See __pthread_cond_wait for a high-level description of the algorithm. - - A correct program must make sure that no waiters are blocked on the condvar - when it is destroyed, and that there are no concurrent signals or - broadcasts. To wake waiters reliably, the program must signal or - broadcast while holding the mutex or after having held the mutex. It must - also ensure that no signal or broadcast are still pending to unblock - waiters; IOW, because waiters can wake up spuriously, the program must - effectively ensure that destruction happens after the execution of those - signal or broadcast calls. - Thus, we can assume that all waiters that are still accessing the condvar - have been woken. We wait until they have confirmed to have woken up by - decrementing __wrefs. */ -int -__pthread_cond_destroy (pthread_cond_t *cond) -{ - LIBC_PROBE (cond_destroy, 1, cond); - - /* Set the wake request flag. We could also spin, but destruction that is - concurrent with still-active waiters is probably neither common nor - performance critical. Acquire MO to synchronize with waiters confirming - that they finished. */ - unsigned int wrefs = atomic_fetch_or_acquire (&cond->__data.__wrefs, 4); - int private = __condvar_get_private (wrefs); - while (wrefs >> 3 != 0) - { - futex_wait_simple (&cond->__data.__wrefs, wrefs, private); - /* See above. */ - wrefs = atomic_load_acquire (&cond->__data.__wrefs); - } - /* The memory the condvar occupies can now be reused. */ - return 0; -} -versioned_symbol (libpthread, __pthread_cond_destroy, - pthread_cond_destroy, GLIBC_2_3_2); |