From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755503Ab2AXQeh (ORCPT ); Tue, 24 Jan 2012 11:34:37 -0500 Received: from mail-iy0-f174.google.com ([209.85.210.174]:51577 "EHLO mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755186Ab2AXQeg (ORCPT ); Tue, 24 Jan 2012 11:34:36 -0500 Date: Tue, 24 Jan 2012 08:34:31 -0800 From: Tejun Heo To: Vivek Goyal Cc: axboe@kernel.dk, ctalbott@google.com, rni@google.com, linux-kernel@vger.kernel.org, Kay Sievers Subject: Re: [PATCH 14/16] blkcg: don't allow or retain configuration of missing devices Message-ID: <20120124163431.GA421@google.com> References: <1327360193-24679-1-git-send-email-tj@kernel.org> <1327360193-24679-15-git-send-email-tj@kernel.org> <20120124154224.GA17291@redhat.com> <20120124155309.GA12906@google.com> <20120124163224.GB17291@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120124163224.GB17291@redhat.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 24, 2012 at 11:32:24AM -0500, Vivek Goyal wrote: > > Yeap, there is. Nice catch. blkg_lookup_create() should be testing > > blk_queue_bypass() instead of blk_queue_dead() and parse_and_set > > should probably retry after a bit. Will update. > > So now group creation fails if queue is in bypass mode. So a per device > rule setting will fail both for cfq and throttling logic while device > is still around. So a user is supposed to retry? How would a user know > that elevator switch is happening and he should retry and till when should > he retry. Ummm... I'm working on the second patch which makes parse_and_set do return restart_syscall(). -- tejun