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49a9f6ab64
This patch fixes the copyright dates from files created by commit8d2c0a5,4b45943, and56cf276.
112 lines
2.9 KiB
C
112 lines
2.9 KiB
C
/* elide.h: Generic lock elision support for powerpc.
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Copyright (C) 2015 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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<http://www.gnu.org/licenses/>. */
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#ifndef ELIDE_PPC_H
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# define ELIDE_PPC_H
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#ifdef ENABLE_LOCK_ELISION
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# include <htm.h>
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# include <elision-conf.h>
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/* Returns true if the lock defined by is_lock_free as elided.
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ADAPT_COUNT is a pointer to per-lock state variable. */
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static inline bool
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__elide_lock (uint8_t *adapt_count, int is_lock_free)
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{
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if (*adapt_count > 0)
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{
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(*adapt_count)--;
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return false;
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}
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for (int i = __elision_aconf.try_tbegin; i > 0; i--)
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{
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if (__builtin_tbegin (0))
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{
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if (is_lock_free)
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return true;
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/* Lock was busy. */
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__builtin_tabort (_ABORT_LOCK_BUSY);
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}
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else
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{
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/* A persistent failure indicates that a retry will probably
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result in another failure. Use normal locking now and
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for the next couple of calls. */
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if (_TEXASRU_FAILURE_PERSISTENT (__builtin_get_texasru ()))
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{
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if (__elision_aconf.skip_lock_internal_abort > 0)
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*adapt_count = __elision_aconf.skip_lock_internal_abort;
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break;
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}
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/* Same logic as above, but for a number of temporary failures in a
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a row. */
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else if (__elision_aconf.skip_lock_out_of_tbegin_retries > 0
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&& __elision_aconf.try_tbegin > 0)
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*adapt_count = __elision_aconf.skip_lock_out_of_tbegin_retries;
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}
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}
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return false;
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}
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# define ELIDE_LOCK(adapt_count, is_lock_free) \
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__elide_lock (&(adapt_count), is_lock_free)
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static inline bool
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__elide_trylock (uint8_t *adapt_count, int is_lock_free, int write)
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{
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if (__elision_aconf.try_tbegin > 0)
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{
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if (write)
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__builtin_tabort (_ABORT_NESTED_TRYLOCK);
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return __elide_lock (adapt_count, is_lock_free);
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}
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return false;
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}
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# define ELIDE_TRYLOCK(adapt_count, is_lock_free, write) \
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__elide_trylock (&(adapt_count), is_lock_free, write)
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static inline bool
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__elide_unlock (int is_lock_free)
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{
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if (is_lock_free)
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{
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__builtin_tend (0);
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return true;
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}
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return false;
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}
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# define ELIDE_UNLOCK(is_lock_free) \
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__elide_unlock (is_lock_free)
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# else
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# define ELIDE_LOCK(adapt_count, is_lock_free) 0
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# define ELIDE_TRYLOCK(adapt_count, is_lock_free, write) 0
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# define ELIDE_UNLOCK(is_lock_free) 0
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#endif /* ENABLE_LOCK_ELISION */
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#endif
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