From patchwork Mon Dec 3 12:32:32 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bart Van Assche X-Patchwork-Id: 1836561 Return-Path: X-Original-To: patchwork-dm-devel@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from mx4-phx2.redhat.com (mx4-phx2.redhat.com [209.132.183.25]) by patchwork1.kernel.org (Postfix) with ESMTP id 31FDF3FC71 for ; Tue, 4 Dec 2012 08:02:34 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by mx4-phx2.redhat.com (8.13.8/8.13.8) with ESMTP id qB47wTB4003288; Tue, 4 Dec 2012 02:58:31 -0500 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id qB3CWndP013947 for ; Mon, 3 Dec 2012 07:32:49 -0500 Received: from mx1.redhat.com (ext-mx14.extmail.prod.ext.phx2.redhat.com [10.5.110.19]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id qB3CWhD3018120 for ; Mon, 3 Dec 2012 07:32:43 -0500 Received: from juliette.telenet-ops.be (juliette.telenet-ops.be [195.130.137.74]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id qB3CWYgX032449 for ; Mon, 3 Dec 2012 07:32:35 -0500 Received: from [192.168.1.104] ([178.119.64.133]) by juliette.telenet-ops.be with bizsmtp id X0YZ1k0032sVyXE060YZjb; Mon, 03 Dec 2012 13:32:34 +0100 Message-ID: <50BC9BE0.30108@acm.org> Date: Mon, 03 Dec 2012 13:32:32 +0100 From: Bart Van Assche User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:16.0) Gecko/20121025 Thunderbird/16.0.2 MIME-Version: 1.0 To: dm-devel@redhat.com X-RedHat-Spam-Score: -1.911 (BAYES_00,RCVD_IN_DNSWL_NONE,SPF_PASS) X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 X-Scanned-By: MIMEDefang 2.68 on 10.5.110.19 X-loop: dm-devel@redhat.com X-Mailman-Approved-At: Tue, 04 Dec 2012 02:57:18 -0500 Cc: Jens Axboe , "Jun'ichi Nomura" , Tejun Heo , Alasdair G Kergon Subject: [dm-devel] [PATCH] dm: Update a source code comment X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk Reply-To: device-mapper development List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com Update a source code comment with the conclusions of the discussion of the patch that introduced this comment (commit a8c32a5). See also http://www.redhat.com/archives/dm-devel/2012-November/msg00003.html. Signed-off-by: Bart Van Assche Cc: Jens Axboe Cc: Alasdair G Kergon Cc: Jun'ichi Nomura Cc: Tejun Heo Cc: stable@vger.kernel.org --- drivers/md/dm.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 77e6eff..0ec0673 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -740,12 +740,7 @@ static void rq_completed(struct mapped_device *md, int rw, int run_queue) if (!md_in_flight(md)) wake_up(&md->wait); - /* - * Run this off this callpath, as drivers could invoke end_io while - * inside their request_fn (and holding the queue lock). Calling - * back into ->request_fn() could deadlock attempting to grab the - * queue lock again. - */ + /* run queue asynchronously to minimize time spent in soft-IRQ ctxt */ if (run_queue) blk_run_queue_async(md->queue);