72 lines
2.0 KiB
C
72 lines
2.0 KiB
C
/* low level locking for pthread library. Generic futex-using version.
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Copyright (C) 2003-2022 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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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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libc_hidden_def (__lll_lock_wait_private)
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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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libc_hidden_def (__lll_lock_wait)
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void
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__lll_lock_wake_private (int *futex)
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{
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lll_futex_wake (futex, 1, LLL_PRIVATE);
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}
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libc_hidden_def (__lll_lock_wake_private)
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void
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__lll_lock_wake (int *futex, int private)
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{
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lll_futex_wake (futex, 1, private);
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}
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libc_hidden_def (__lll_lock_wake)
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#if ENABLE_ELISION_SUPPORT
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int __pthread_force_elision;
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libc_hidden_data_def (__pthread_force_elision)
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#endif
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