Commit 34342e86 authored Sep 03, 2005 by Eric Dumazet Committed by Linus Torvalds Sep 05, 2005

[PATCH] mm/slab.c: prefetchw the start of new allocated objects



Mostobjects returned by __cache_alloc() will be written by the caller,
(but not all callers want to write all the object, but just at the
begining) prefetchw() tells the modern CPU to think about the future
writes, ie start some memory transactions in advance.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent 61e06037

mm/slab.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -2166,7 +2166,9 @@ static inline void __cache_alloc(kmem_cache_t cachep, unsigned int __nocast fl
		objp = cache_alloc_refill(cachep, flags);
		}
		local_irq_restore(save_flags);
		objp = cache_alloc_debugcheck_after(cachep, flags, objp, __builtin_return_address(0));
		objp = cache_alloc_debugcheck_after(cachep, flags, objp,
		__builtin_return_address(0));
		prefetchw(objp);
		return objp;
		}

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