Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750708AbWB0JYx (ORCPT ); Mon, 27 Feb 2006 04:24:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750838AbWB0JYx (ORCPT ); Mon, 27 Feb 2006 04:24:53 -0500 Received: from pentafluge.infradead.org ([213.146.154.40]:13013 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S1750708AbWB0JYw (ORCPT ); Mon, 27 Feb 2006 04:24:52 -0500 Subject: Re: [Patch 5/7] synchronous block I/O delays From: Arjan van de Ven To: Shailabh Nagar Cc: linux-kernel , lse-tech In-Reply-To: <4402C2AF.2030008@watson.ibm.com> References: <1141026996.5785.38.camel@elinux04.optonline.net> <1141028448.5785.64.camel@elinux04.optonline.net> <1141028957.2992.61.camel@laptopd505.fenrus.org> <4402C2AF.2030008@watson.ibm.com> Content-Type: text/plain Date: Mon, 27 Feb 2006 10:24:50 +0100 Message-Id: <1141032290.2992.80.camel@laptopd505.fenrus.org> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 (2.2.3-2.fc4) Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 720 Lines: 27 On Mon, 2006-02-27 at 04:13 -0500, Shailabh Nagar wrote: > Arjan van de Ven wrote: > > >>+static inline void delayacct_blkio(void) > >>+{ > >>+ if (unlikely(current->delays && delayacct_on)) > >>+ __delayacct_blkio(); > >>+} > >> > >> > > > >why is this unlikely? > > > > > delayacct_on is expected to be off most of the time, hence the compound is > unlikely too. ok that opens the question: why is this a runtime tunable? Is it really worth all this complexity? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/