Re: [PATCH] atomic: add *_dec_not_zero
From: Russell King - ARM Linux <hidden>
Date: 2011-05-08 09:24:34
Also in:
linux-arch, linux-arm-kernel, linux-mips, linux-s390, linux-sh, linuxppc-dev, lkml, sparclinux
On Tue, May 03, 2011 at 11:30:35PM +0200, Sven Eckelmann wrote:
Introduce an *_dec_not_zero operation. Make this a special case of *_add_unless because batman-adv uses atomic_dec_not_zero in different places like re-broadcast queue or aggregation queue management. There are other non-final patches which may also want to use this macro.
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quoted hunk ↗ jump to hunk
diff --git a/arch/arm/include/asm/atomic.h b/arch/arm/include/asm/atomic.h index 7e79503..a005265 100644 --- a/arch/arm/include/asm/atomic.h +++ b/arch/arm/include/asm/atomic.h@@ -218,6 +218,7 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u) return c != u; } #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) +#define atomic_dec_not_zero(v) atomic_add_unless((v), -1, 0) #define atomic_inc(v) atomic_add(1, v) #define atomic_dec(v) atomic_sub(1, v)@@ -459,6 +460,7 @@ static inline int atomic64_add_unless(atomic64_t *v, u64 a, u64 u) #define atomic64_dec_return(v) atomic64_sub_return(1LL, (v)) #define atomic64_dec_and_test(v) (atomic64_dec_return((v)) == 0) #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1LL, 0LL) +#define atomic64_dec_not_zero(v) atomic64_add_unless((v), -1LL, 0LL) #else /* !CONFIG_GENERIC_ATOMIC64 */ #include <asm-generic/atomic64.h>
Do we need atomic_dec_not_zero() et.al. in every arch header - is there no generic header which it could be added to?