[x86] Fix prefetch instruction

[Christoph Lameter]

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@xxxxxxxxxxxxxxx>
Signed-off-by: Christoph Lameter <cl@xxxxxxxxx>


---
 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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