From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: [PATCH -mm] ide_end_drive_cmd(): avoid instruction pipeline stall Date: Fri, 30 Jun 2006 11:00:18 -0700 Message-ID: <20060630110018.f45b40e2.akpm@osdl.org> References: <20060630161351.GA17434@rhlx01.fht-esslingen.de> <1151688416.31392.66.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.osdl.org ([65.172.181.4]:55479 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1751837AbWF3SAf (ORCPT ); Fri, 30 Jun 2006 14:00:35 -0400 In-Reply-To: <1151688416.31392.66.camel@localhost.localdomain> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Alan Cox Cc: andi@rhlx01.fht-esslingen.de, B.Zolnierkiewicz@elka.pw.edu.pl, linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org On Fri, 30 Jun 2006 18:26:56 +0100 Alan Cox wrote: > Ar Gwe, 2006-06-30 am 18:13 +0200, ysgrifennodd Andreas Mohr: > > Use an independently-formatted "unsigned int" for data instead of a > > restrictive "u16" to avoid instruction fetch pipeline stalls > > probably caused by the byte calculations later. > > drivers/ide is on its way out. Like sound/oss ;) > I'm also curious that this shows up given > that the inw() is going to cause a PCI sequence and stall the CPU > entirely for ages anyway. I guess because he was profiling for IFU_MEM_STALL, not for wall-time. > NAK because > 1. This is a gcc problem > 2. Not everyone is using an intel x86-32 box which has such problems > 3. IDE is in life-support mode and the relatives are already planning > the flowers. Well. If the patch breaks anything we can dine on hats for a month. Seems pretty inoffensive to me.