Re: [patch] x86, mm: pass in 'total' to __copy_from_user_*nocache()

Nick Piggin wrote:
> 
> I would expect any high performance CPU these days to combine entries
> in the store queue, even for normal store instructions (especially for
> linear memcpy patterns). Isn't this likely to be the case?
> 

Actually, that is often not the case simply because it doesn't buy that
much.  The big win comes when you don't read a whole cache line in from
memory, but that is a property of the cache, not the store queue.

	-hpa

--

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.