From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [PATCH] Shrink struct dst_entry a bit Date: Tue, 13 Mar 2007 15:10:41 +0100 Message-ID: <200703131510.41651.dada1@cosmosbay.com> References: <200703131448.15193.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, davem@davemloft.net To: Andi Kleen Return-path: Received: from pfx2.jmh.fr ([194.153.89.55]:41283 "EHLO pfx2.jmh.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030308AbXCMOKe (ORCPT ); Tue, 13 Mar 2007 10:10:34 -0400 In-Reply-To: <200703131448.15193.ak@suse.de> Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Tuesday 13 March 2007 14:48, Andi Kleen wrote: > The ICMP rate limiting state can be shorts, we don't send that many ICMPs. > Changing flags to short and reorder fields to be sorted by size to avoid > holes. Move cold fields towards the end. > Nope, you cannot break the reordering I've done one month ago. http://git.kernel.org/?p=linux/kernel/git/davem/net-2.6.22.git;a=commit;h=1e19e02ca0c5e33ea73a25127dbe6c3b8fcaac4b [NET]: Reorder fields of struct dst_entry This last patch (but not least :) ) finally moves the next pointer at the end of struct dst_entry. This permits to perform route cache lookups with a minimal cost of one cache line per entry, instead of two. Both 32bits and 64bits platforms benefit from this new layout.