Date: Mon, 30 Nov 2009 10:09:39 -0600 (CST)
From: Christoph Lameter <cl@linux-foundation.org>
To: Pekka Enberg <penberg@cs.helsinki.fi>
cc: Tim Blechmann <tim@klingt.org>, Ingo Molnar <mingo@elte.hu>,
       linux-kernel@vger.kernel.org, Nick Piggin <npiggin@suse.de>,
       davem@davemloft.net, netdev@vger.kernel.org
Subject: Re: [PATCH 3/5] slab.c: remove branch hint
In-Reply-To: <4B138AC2.7080008@cs.helsinki.fi>
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On Mon, 30 Nov 2009, Pekka Enberg wrote:

> OK, so it's the generic alloc_skb() function that keeps hitting
> kmem_cache_alloc_node() with "-1". Christoph, are you okay with removing the
> unlikely() annotation from __cache_alloc_node()?

Yes. Lets look for other cases in the allocators too.
kmem_cache_alloc_node used to be mainly used for off node allocations but
the network alloc_skb() case shows that this is changing now.

I hope the users of kmem_cache_alloc_node() realize that using -1 is not
equivalent to kmem_cache_alloc(). kmem_cache_alloc follows numa policies
for memory allocations. kmem_cache_alloc_node() does not.


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