From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757587Ab2BAVTs (ORCPT ); Wed, 1 Feb 2012 16:19:48 -0500 Received: from mail-pw0-f46.google.com ([209.85.160.46]:48353 "EHLO mail-pw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757494Ab2BAVT1 (ORCPT ); Wed, 1 Feb 2012 16:19:27 -0500 From: Tejun Heo To: axboe@kernel.dk, vgoyal@redhat.com Cc: ctalbott@google.com, rni@google.com, linux-kernel@vger.kernel.org, Tejun Heo Subject: [PATCH 02/11] block: relocate elevator initialized test from blk_cleanup_queue() to blk_drain_queue() Date: Wed, 1 Feb 2012 13:19:07 -0800 Message-Id: <1328131156-13290-3-git-send-email-tj@kernel.org> X-Mailer: git-send-email 1.7.7.3 In-Reply-To: <1328131156-13290-1-git-send-email-tj@kernel.org> References: <1328131156-13290-1-git-send-email-tj@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org blk_cleanup_queue() may be called for a queue which doesn't have elevator initialized to skip invoking blk_drain_queue(). blk_drain_queue() will be used for other purposes too and may be called for such half-initialized queues from other paths. Move q->elevator test into blk_drain_queue(). Signed-off-by: Tejun Heo Cc: Vivek Goyal --- block/blk-core.c | 16 +++++++++------- 1 files changed, 9 insertions(+), 7 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index 1b73d06..ddda1cc 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -359,6 +359,13 @@ EXPORT_SYMBOL(blk_put_queue); */ void blk_drain_queue(struct request_queue *q, bool drain_all) { + /* + * The caller might be trying to tear down @q before its elevator + * is initialized, in which case we don't want to call into it. + */ + if (!q->elevator) + return; + while (true) { bool drain = false; int i; @@ -468,13 +475,8 @@ void blk_cleanup_queue(struct request_queue *q) spin_unlock_irq(lock); mutex_unlock(&q->sysfs_lock); - /* - * Drain all requests queued before DEAD marking. The caller might - * be trying to tear down @q before its elevator is initialized, in - * which case we don't want to call into draining. - */ - if (q->elevator) - blk_drain_queue(q, true); + /* drain all requests queued before DEAD marking */ + blk_drain_queue(q, true); /* @q won't process any more request, flush async actions */ del_timer_sync(&q->backing_dev_info.laptop_mode_wb_timer); -- 1.7.7.3