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878fe624d4
The idea is to make NPTL implementation to use on the functions provided by futex-internal.h. Checked on x86_64-linux-gnu and i686-linux-gnu. Reviewed-by: Lukasz Majewski <lukma@denx.de>
56 lines
1.7 KiB
C
56 lines
1.7 KiB
C
/* low level locking for pthread library. Generic futex-using version.
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Copyright (C) 2003-2020 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Paul Mackerras <paulus@au.ibm.com>, 2003.
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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 <sysdep.h>
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#include <futex-internal.h>
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#include <atomic.h>
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#include <stap-probe.h>
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void
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__lll_lock_wait_private (int *futex)
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{
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if (atomic_load_relaxed (futex) == 2)
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goto futex;
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while (atomic_exchange_acquire (futex, 2) != 0)
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{
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futex:
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LIBC_PROBE (lll_lock_wait_private, 1, futex);
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futex_wait ((unsigned int *) futex, 2, LLL_PRIVATE); /* Wait if *futex == 2. */
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}
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}
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/* This function doesn't get included in libc. */
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#if IS_IN (libpthread)
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void
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__lll_lock_wait (int *futex, int private)
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{
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if (atomic_load_relaxed (futex) == 2)
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goto futex;
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while (atomic_exchange_acquire (futex, 2) != 0)
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{
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futex:
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LIBC_PROBE (lll_lock_wait, 1, futex);
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futex_wait ((unsigned int *) futex, 2, private); /* Wait if *futex == 2. */
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}
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}
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#endif
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