diff options
| author | Catalin Marinas <catalin.marinas@arm.com> | 2007-02-28 12:30:38 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2007-03-02 11:59:00 +0000 |
| commit | 9623b3732d11b0a18d9af3419f680d27ea24b014 (patch) | |
| tree | 9f00b744060872ca3ad1518002f67376d3050d45 | |
| parent | 5bfe8cb62127b5eb799f5724764abe914e49860e (diff) | |
| download | linux-9623b3732d11b0a18d9af3419f680d27ea24b014.tar.bz2 | |
[ARM] 4241/1: Define mb() as compiler barrier on a uniprocessor system
Currently, the mb() is defined as a DMB operation on ARMv6, even for
UP systems. This patch defines mb() as a compiler barrier only. For
the SMP case, the smp_* variants should be used anyway and the patch
defines them as DMB.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| -rw-r--r-- | include/asm-arm/system.h | 40 |
1 files changed, 19 insertions, 21 deletions
diff --git a/include/asm-arm/system.h b/include/asm-arm/system.h index f4386906b200..f06d8a43fdee 100644 --- a/include/asm-arm/system.h +++ b/include/asm-arm/system.h @@ -167,11 +167,25 @@ extern unsigned int user_debug; : : "r" (0) : "memory") #define dmb() __asm__ __volatile__ ("" : : : "memory") #endif -#define mb() dmb() -#define rmb() mb() -#define wmb() mb() -#define read_barrier_depends() do { } while(0) -#define set_mb(var, value) do { var = value; mb(); } while (0) + +#define mb() barrier() +#define rmb() barrier() +#define wmb() barrier() +#define read_barrier_depends() do { } while(0) + +#ifdef CONFIG_SMP +#define smp_mb() dmb() +#define smp_rmb() dmb() +#define smp_wmb() dmb() +#define smp_read_barrier_depends() read_barrier_depends() +#else +#define smp_mb() barrier() +#define smp_rmb() barrier() +#define smp_wmb() barrier() +#define smp_read_barrier_depends() read_barrier_depends() +#endif /* CONFIG_SMP */ + +#define set_mb(var, value) do { var = value; smp_mb(); } while (0) #define nop() __asm__ __volatile__("mov\tr0,r0\t@ nop\n\t"); extern unsigned long cr_no_alignment; /* defined in entry-armv.S */ @@ -243,22 +257,6 @@ static inline void sched_cacheflush(void) { } -#ifdef CONFIG_SMP - -#define smp_mb() mb() -#define smp_rmb() rmb() -#define smp_wmb() wmb() -#define smp_read_barrier_depends() read_barrier_depends() - -#else - -#define smp_mb() barrier() -#define smp_rmb() barrier() -#define smp_wmb() barrier() -#define smp_read_barrier_depends() do { } while(0) - -#endif /* CONFIG_SMP */ - #if defined(CONFIG_CPU_SA1100) || defined(CONFIG_CPU_SA110) /* * On the StrongARM, "swp" is terminally broken since it bypasses the |