From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net-next-2.6] filter: optimize sk_run_filter Date: Fri, 19 Nov 2010 09:21:29 -0800 (PST) Message-ID: <20101119.092129.112602956.davem@davemloft.net> References: <1290185759.3034.179.camel@edumazet-laptop> <20101119.090516.104057453.davem@davemloft.net> <20101119091537.5d1fed2e@nehalam> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: eric.dumazet@gmail.com, hagen@jauu.net, netdev@vger.kernel.org, xiaosuo@gmail.com To: shemminger@vyatta.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:59555 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755406Ab0KSRVG (ORCPT ); Fri, 19 Nov 2010 12:21:06 -0500 In-Reply-To: <20101119091537.5d1fed2e@nehalam> Sender: netdev-owner@vger.kernel.org List-ID: From: Stephen Hemminger Date: Fri, 19 Nov 2010 09:15:37 -0800 > On Fri, 19 Nov 2010 09:05:16 -0800 (PST) > David Miller wrote: > >> From: Eric Dumazet >> Date: Fri, 19 Nov 2010 17:55:59 +0100 >> >> > Unfortunatly on x86_32 it also chose that f_k was more valuable in a cpu >> > register and accumulator A lost its register to get a stack slot >> > instead. >> >> Ok that tradeoff is terrible, but it depends upon knowledge we haven't >> given to the compiler (yet). >> >> Let me think about this a bit... > > Are 'register' modifiers a no-op on current GCC? Yes, they are.