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SubjectRe: PATCH 2.3.26: kmalloc GFP_ZERO
>>>>> "Jeff" == Jeff Garzik <> writes:

Jeff> If you add "kcalloc" instead of hacking "kmalloc" as I did,
Jeff> drivers wanting zeroed pages make the conscious decision of
Jeff> calling another function, with a potentially slower path.

I still don't see the point of doing a kcalloc() except for making
driver code slightly prettier. You have to remember that full pages
grabbed by the mm system do not come out of kmalloc() but

Jeff> Such a split would also make it easier to enumerate
Jeff> architecture-dependent paths. For some architectures may choose
Jeff> the default -- kmalloc+memset -- and other archs can choose a
Jeff> page-zeroing idle task, all without affecting
Jeff> kmalloc/kmem_cache_alloc

It's possible that pre zeroing pages for the mm system might be a win,
and if so it is probably a good thing to explore, however we are
talking two different things here. In the pre-zeroed cage you don't go
through kmalloc and kmem_cache_alloc (SLAB) at all.


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