From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: [PATCH RFC 0/4] use scatter lists for all block pc requests and simplify hw handlers Date: Thu, 9 Jun 2005 13:54:33 +0200 Message-ID: <20050609115433.GS5140@suse.de> References: <1117847972.23638.62.camel@mina> <1117901234.5005.9.camel@mulgrave> <1117955727.4961.8.camel@mina> <20050606190205.GA6817@us.ibm.com> <1118157976.42a5bc98d6f75@webmail.cs.wisc.edu> <20050607182317.GA12959@us.ibm.com> <42A711BC.9020108@cs.wisc.edu> <20050609000830.GA20616@us.ibm.com> <20050609061838.GB5140@suse.de> <1118317904.5043.3.camel@mulgrave> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1118317904.5043.3.camel@mulgrave> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: James Bottomley Cc: Mike Christie , device-mapper development , linux-scsi , Patrick Mansfield List-Id: linux-scsi@vger.kernel.org On Thu, Jun 09 2005, James Bottomley wrote: > On Thu, 2005-06-09 at 08:18 +0200, Jens Axboe wrote: > > > So use a req->retries instead of the fail fast flag? > > > > Would be fine. Some drivers are messing with ->errors for that anyways, > > so would be nice to clean that up. > > > > It would need to be done _very_ carefully though! > > Actually, I think there's still a need for both. Fail fast implies more > than simply no retry. In the SCSI case it should eventually mean fail > the command before we begin transport recovery (at the moment, we simply > use the command in transport recovery, however long it takes, and then > return the failure). I tend to agree, FAILFAST does have a use outside of normal retry logic. -- Jens Axboe