From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: elevator priorities vs. full request queues Date: Tue, 13 Jul 2004 14:35:44 +0200 Sender: linux-fsdevel-owner@vger.kernel.org Message-ID: <20040713123541.GA28956@suse.de> References: <20040622012502.B1325@almesberger.net> <20040622074852.GW12881@suse.de> <20040622052644.D1325@almesberger.net> <20040622101434.GB12881@suse.de> <20040622160859.I1325@almesberger.net> <20040623101430.GI1120@suse.de> <20040712205227.A12285@almesberger.net> <20040713053749.GA14759@suse.de> <20040713092904.A1795@almesberger.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-fsdevel@vger.kernel.org Return-path: Received: from ns.virtualhost.dk ([195.184.98.160]:42209 "EHLO virtualhost.dk") by vger.kernel.org with ESMTP id S264941AbUGMMfr (ORCPT ); Tue, 13 Jul 2004 08:35:47 -0400 To: Werner Almesberger Content-Disposition: inline In-Reply-To: <20040713092904.A1795@almesberger.net> List-Id: linux-fsdevel.vger.kernel.org On Tue, Jul 13 2004, Werner Almesberger wrote: > > Maybe it would be more logical to assign 'default' priority in > > bio_init(), in fact? > > What made me shy away from this is that bio_init and bio_alloc > seem to get called from contexts where "current" wouldn't > necessarily have anything to do with the process that has > actually initiated the IO. > > For example, I'm not sure if the calls from ide-scsi.c, when > it builds requests piece by piece, are safe in this regard. That's not really what I meant - 'default' priority isn't tied to the process. It's just that if default io prio was something other than 0, then it would make sense to set it there. Say if the range was 0-15, and you wanted 7 to be 'in the middle' default priority. But I suppose you just want io submission to set it, in which case it doesn't matter what bio_init() sets it to. -- Jens Axboe