[PATCH 1/2] ARM: L2X0: add explicit cpu_relax() for busy wait loop

[PATCH 1/2] ARM: L2X0: add explicit cpu_relax() for busy wait loop

[Barry Song]

using cpu_relax in busy loops is a well-known idiom in the kernel. It's more
for documentation purposes than technically needed here.

Cc: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
---
 arch/arm/mm/cache-l2x0.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c
index 2ebbc7c..966b3bd 100644
--- a/arch/arm/mm/cache-l2x0.c
+++ b/arch/arm/mm/cache-l2x0.c
@@ -37,7 +37,7 @@ static inline void cache_wait_way(void __iomem *reg, unsigned long mask)
 {
 	/* wait for cache operation by line or way to complete */
 	while (readl_relaxed(reg) & mask)
-		;
+		cpu_relax();
 }
 
 #ifdef CONFIG_CACHE_PL310
-- 
1.7.1



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[PATCH 1/2] ARM: L2X0: add explicit cpu_relax() for busy wait loop

[Arnd Bergmann]

On Wednesday 24 August 2011, Barry Song wrote:
> using cpu_relax in busy loops is a well-known idiom in the kernel. It's more
> for documentation purposes than technically needed here.
> 
> Cc: Jamie Iles <jamie@jamieiles.com>
> Signed-off-by: Barry Song <Baohua.Song@csr.com>

Acked-by: Arnd Bergmann <arnd@arndb.de>

[PATCH 1/2] ARM: L2X0: add explicit cpu_relax() for busy wait loop

[Jamie Iles]

Hi Barry,

On Tue, Aug 23, 2011 at 06:30:11PM -0700, Barry Song wrote:
> using cpu_relax in busy loops is a well-known idiom in the kernel. It's more
> for documentation purposes than technically needed here.
> 
> Cc: Jamie Iles <jamie@jamieiles.com>

Reviewed-by: Jamie Iles <jamie@jamieiles.com>

for both patches!

Jamie