e79bee24fd
The x86 implementation of atomic_dec_if_positive is quite generic, so make it available to all architectures. This is needed for "swap: add a simple detector for inappropriate swapin readahead". [akpm@linux-foundation.org: do the "#define foo foo" trick in the conventional manner] Signed-off-by: Shaohua Li <shli@fusionio.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: Rik van Riel <riel@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michal Simek <monstr@monstr.eu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
27 lines
587 B
C
27 lines
587 B
C
#ifndef _ASM_MICROBLAZE_ATOMIC_H
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#define _ASM_MICROBLAZE_ATOMIC_H
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#include <asm/cmpxchg.h>
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#include <asm-generic/atomic.h>
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#include <asm-generic/atomic64.h>
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/*
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* Atomically test *v and decrement if it is greater than 0.
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* The function returns the old value of *v minus 1.
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*/
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static inline int atomic_dec_if_positive(atomic_t *v)
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{
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unsigned long flags;
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int res;
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local_irq_save(flags);
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res = v->counter - 1;
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if (res >= 0)
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v->counter = res;
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local_irq_restore(flags);
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return res;
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}
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#define atomic_dec_if_positive atomic_dec_if_positive
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#endif /* _ASM_MICROBLAZE_ATOMIC_H */
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