From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 30 Mar 2005 10:13:49 -0800 (PST) From: Christoph Lameter Subject: Re: API changes to the slab allocator for NUMA memory allocation In-Reply-To: <424AE7F7.3080508@colorfullife.com> Message-ID: References: <20050315204110.6664771d.akpm@osdl.org> <42387C2E.4040106@colorfullife.com> <273220000.1110999247@[10.10.2.4]> <4238845E.5060304@colorfullife.com> <424A3FA0.9030403@colorfullife.com> <424AE7F7.3080508@colorfullife.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Manfred Spraul Cc: "Martin J. Bligh" , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org, shai@scalex86.org List-ID: On Wed, 30 Mar 2005, Manfred Spraul wrote: > Correct, I was thinking about the NUMA case. > You've decided to add one register load to every call of kmalloc. On > i386, kmalloc_node() is a 24-byte function. I'd bet that adding the node > parameter to every call of kmalloc causes a .text increase larger than > 240 bytes. And I have not yet considered that you have increased the > number of conditional branches in every kmalloc(32,GFP_KERNEL) call by > 33%, i.e. from 3 to 4 conditional branch instructions. > I'd add an explicit kmalloc_node function. Attached is a prototype > patch. You'd have to reintroduce the flags field to > kmem_cache_alloc_node() and update kmalloc_node. > The patch was manually edited, I hope it applies to a recent tree ;-) > > What do you think? Looks fine to me. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: aart@kvack.org