forked from luck/tmp_suning_uos_patched
26333576fd
Introduce test_and_set_bit_lock / clear_bit_unlock bitops with lock semantics. Convert all architectures to use the generic implementation. Signed-off-by: Nick Piggin <npiggin@suse.de> Acked-By: David Howells <dhowells@redhat.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Haavard Skinnemoen <hskinnemoen@atmel.com> Cc: Bryan Wu <bryan.wu@analog.com> Cc: Mikael Starvik <starvik@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Greg Ungerer <gerg@uclinux.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Matthew Wilcox <willy@debian.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Richard Curnow <rc@rc0.org.uk> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp> Cc: Andi Kleen <ak@muc.de> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
46 lines
1.3 KiB
C
46 lines
1.3 KiB
C
#ifndef _ASM_GENERIC_BITOPS_LOCK_H_
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#define _ASM_GENERIC_BITOPS_LOCK_H_
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/**
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* test_and_set_bit_lock - Set a bit and return its old value, for lock
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* @nr: Bit to set
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* @addr: Address to count from
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*
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* This operation is atomic and provides acquire barrier semantics.
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* It can be used to implement bit locks.
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*/
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#define test_and_set_bit_lock(nr, addr) test_and_set_bit(nr, addr)
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/**
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* clear_bit_unlock - Clear a bit in memory, for unlock
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* @nr: the bit to set
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* @addr: the address to start counting from
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*
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* This operation is atomic and provides release barrier semantics.
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*/
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#define clear_bit_unlock(nr, addr) \
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do { \
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smp_mb__before_clear_bit(); \
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clear_bit(nr, addr); \
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} while (0)
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/**
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* __clear_bit_unlock - Clear a bit in memory, for unlock
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* @nr: the bit to set
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* @addr: the address to start counting from
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*
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* This operation is like clear_bit_unlock, however it is not atomic.
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* It does provide release barrier semantics so it can be used to unlock
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* a bit lock, however it would only be used if no other CPU can modify
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* any bits in the memory until the lock is released (a good example is
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* if the bit lock itself protects access to the other bits in the word).
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*/
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#define __clear_bit_unlock(nr, addr) \
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do { \
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smp_mb(); \
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__clear_bit(nr, addr); \
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} while (0)
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#endif /* _ASM_GENERIC_BITOPS_LOCK_H_ */
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