Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757751Ab1E1CJt (ORCPT ); Fri, 27 May 2011 22:09:49 -0400 Received: from mail-pv0-f174.google.com ([74.125.83.174]:64085 "EHLO mail-pv0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753675Ab1E1CJs (ORCPT ); Fri, 27 May 2011 22:09:48 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; b=X946KsD1Uzlrwy6KryHVJVPHlowjIAOpuyTe9aSHzJuoIdlaFtGP8kAuYnMroqyvp0 ZYXonyCuF5o86DX8PY5mlX+JAZqfCTyzJcz7FF5q0f2iv/EQQ7AONne57af8s27Vz96c ouGLHs3iQigM1KCfUMUYcE/8WfM2EPPSmoHMc= Subject: Re: [PATCH 1/2] blktrace: treat flush as barrier From: Namhyung Kim To: Christoph Hellwig Cc: Jens Axboe , Mike Snitzer , "linux-kernel@vger.kernel.org" , Tejun Heo In-Reply-To: <20110527202747.GA4803@infradead.org> References: <1306501883-23498-1-git-send-email-namhyung@gmail.com> <20110527131237.GA27647@infradead.org> <1306509182.1351.1.camel@leonhard> <4DE006C5.4010906@fusionio.com> <20110527202747.GA4803@infradead.org> Content-Type: text/plain; charset="UTF-8" Date: Sat, 28 May 2011 11:09:41 +0900 Message-ID: <1306548581.1679.12.camel@leonhard> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1222 Lines: 38 2011-05-27 (금), 16:27 -0400, Christoph Hellwig: > On Fri, May 27, 2011 at 10:17:09PM +0200, Jens Axboe wrote: > > Agree on Christophs comments, we should not pretend they are the same > > (since they are not). Since flush is a request on its own, F works > > nicely. For FUA it's associated with a write, so F should work there too > > indicating Write Fua (and easily humanly parsed as that, or Write > > Flush). WU would look confusing. > > REQ_FLUSH can also be set on a write bio, it only gets split at the > request level. And even there we're at least pondering allowing it > to stay as part of the write for some paravirtualized storage protocols. > Hi, AFAIK FLUSH always precedes WRITE and then followed by FUA, so how about using the same F for both of them and distinguishing by position? - WRITE: W - WRITE_FLUSH: FW - WRITE_FUA: WF - WRITE_FLUSH_FUA: FWF Or using lower-case 'f' for FUA? Thanks. -- Regards, Namhyung Kim -- 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/