forked from Minki/linux
09a01c0ccb
Xtensa SMP has compare-and-swap which is fully serializing, therefore
its exising smp_mb__{before,after}_clear_bit() appear unduly heavy.
Implement the new barriers as barrier().
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/n/tip-e9rqjxr1m1ejsob9p433kmji@git.kernel.org
Cc: Chris Zankel <chris@zankel.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-xtensa@linux-xtensa.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
22 lines
538 B
C
22 lines
538 B
C
/*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*
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* Copyright (C) 2001 - 2012 Tensilica Inc.
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*/
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#ifndef _XTENSA_SYSTEM_H
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#define _XTENSA_SYSTEM_H
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#define mb() ({ __asm__ __volatile__("memw" : : : "memory"); })
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#define rmb() barrier()
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#define wmb() mb()
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#define smp_mb__before_atomic() barrier()
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#define smp_mb__after_atomic() barrier()
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#include <asm-generic/barrier.h>
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#endif /* _XTENSA_SYSTEM_H */
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