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Subject[x86] Fix prefetch instruction
The prefetchnta instruction used for prefetching on x86 is a special instruction
used for streaming that is usually used to avoid polluting the l2 and l3 caches.
The cacheline will be evicted rapidly.

What we need is a prefetch that puts the cacheline in all levels of the cache hierachy instead.
Change the instruction to do that.

Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Christoph Lameter <cl@linux.com>


---
arch/x86/include/asm/processor.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-2.6/arch/x86/include/asm/processor.h
===================================================================
--- linux-2.6.orig/arch/x86/include/asm/processor.h 2011-08-04 13:12:39.000000000 -0500
+++ linux-2.6/arch/x86/include/asm/processor.h 2011-08-04 13:16:31.000000000 -0500
@@ -829,7 +829,7 @@ extern char ignore_fpu_irq;
static inline void prefetch(const void *x)
{
alternative_input(BASE_PREFETCH,
- "prefetchnta (%1)",
+ "prefetcht0 (%1)",
X86_FEATURE_XMM,
"r" (x));
}

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