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Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
63 lines
2.6 KiB
C
63 lines
2.6 KiB
C
/* Copyright (C) 2002-2019 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<https://www.gnu.org/licenses/>. */
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#include <errno.h>
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#include <shlib-compat.h>
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#include "pthreadP.h"
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#include <stap-probe.h>
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#include <atomic.h>
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#include <futex-internal.h>
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#include "pthread_cond_common.c"
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/* See __pthread_cond_wait for a high-level description of the algorithm.
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A correct program must make sure that no waiters are blocked on the condvar
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when it is destroyed, and that there are no concurrent signals or
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broadcasts. To wake waiters reliably, the program must signal or
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broadcast while holding the mutex or after having held the mutex. It must
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also ensure that no signal or broadcast are still pending to unblock
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waiters; IOW, because waiters can wake up spuriously, the program must
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effectively ensure that destruction happens after the execution of those
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signal or broadcast calls.
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Thus, we can assume that all waiters that are still accessing the condvar
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have been woken. We wait until they have confirmed to have woken up by
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decrementing __wrefs. */
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int
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__pthread_cond_destroy (pthread_cond_t *cond)
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{
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LIBC_PROBE (cond_destroy, 1, cond);
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/* Set the wake request flag. We could also spin, but destruction that is
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concurrent with still-active waiters is probably neither common nor
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performance critical. Acquire MO to synchronize with waiters confirming
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that they finished. */
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unsigned int wrefs = atomic_fetch_or_acquire (&cond->__data.__wrefs, 4);
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int private = __condvar_get_private (wrefs);
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while (wrefs >> 3 != 0)
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{
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futex_wait_simple (&cond->__data.__wrefs, wrefs, private);
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/* See above. */
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wrefs = atomic_load_acquire (&cond->__data.__wrefs);
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}
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/* The memory the condvar occupies can now be reused. */
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return 0;
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}
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versioned_symbol (libpthread, __pthread_cond_destroy,
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pthread_cond_destroy, GLIBC_2_3_2);
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