From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756168AbYHARfA (ORCPT ); Fri, 1 Aug 2008 13:35:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751885AbYHAReu (ORCPT ); Fri, 1 Aug 2008 13:34:50 -0400 Received: from mga03.intel.com ([143.182.124.21]:16655 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751388AbYHAReu (ORCPT ); Fri, 1 Aug 2008 13:34:50 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.31,294,1215414000"; d="scan'208";a="28590279" Subject: Re: [PULL REQUEST] md bug fixes and minor improvements From: Dan Williams To: Jens Axboe Cc: Linus Torvalds , Neil Brown , Arthur Jones , Linux Kernel Mailing List , linux-raid@vger.kernel.org, "Rafael J. Wysocki" In-Reply-To: <20080801172231.GF20055@kernel.dk> References: <18578.31924.259887.735206@notabene.brown> <20080801172231.GF20055@kernel.dk> Content-Type: text/plain Date: Fri, 01 Aug 2008 10:34:48 -0700 Message-Id: <1217612088.24551.5.camel@dwillia2-linux.ch.intel.com> Mime-Version: 1.0 X-Mailer: Evolution 2.12.3 (2.12.3-5.fc8) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2008-08-01 at 19:22 +0200, Jens Axboe wrote: > It is a bit asymmetrical, largely due to the fact that the ->unplug_fn() > itself grabs the lock. The below patch should fix it, since Neil has > added a proper queue lock to the md queues. If someone can confirm that > this fixes it, I'll queue up a patch with proper descriptions. > > > I guess Jens is gone too.. > > I'm back, just been busy this week :-) > > diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c > index 621a272..f19b52f 100644 > --- a/drivers/md/bitmap.c > +++ b/drivers/md/bitmap.c > @@ -1234,7 +1234,9 @@ int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sect > case 0: > bitmap_file_set_bit(bitmap, offset); > bitmap_count_page(bitmap,offset, 1); > + spin_lock_irq(&bitmap->mddev->queue->queue_lock); > blk_plug_device(bitmap->mddev->queue); > + spin_unlock_irq(&bitmap->mddev->queue->queue_lock); > /* fall through */ > case 1: > *bmc = 2; > We also need to protect the blk_plug_device call a few lines down (and an obvious compile fix). diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c index 621a272..c1b07e7 100644 --- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -1224,7 +1224,9 @@ int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sect prepare_to_wait(&bitmap->overflow_wait, &__wait, TASK_UNINTERRUPTIBLE); spin_unlock_irq(&bitmap->lock); + spin_lock_irq(bitmap->mddev->queue->queue_lock); blk_unplug(bitmap->mddev->queue); + spin_unlock_irq(bitmap->mddev->queue->queue_lock); schedule(); finish_wait(&bitmap->overflow_wait, &__wait); continue; @@ -1234,7 +1236,9 @@ int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sect case 0: bitmap_file_set_bit(bitmap, offset); bitmap_count_page(bitmap,offset, 1); + spin_lock_irq(bitmap->mddev->queue->queue_lock); blk_plug_device(bitmap->mddev->queue); + spin_unlock_irq(bitmap->mddev->queue->queue_lock); /* fall through */ case 1: *bmc = 2;