From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756560Ab2GCOkD (ORCPT ); Tue, 3 Jul 2012 10:40:03 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44273 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751729Ab2GCOkB (ORCPT ); Tue, 3 Jul 2012 10:40:01 -0400 Date: Tue, 3 Jul 2012 10:39:49 -0400 From: Vivek Goyal To: Paolo Bonzini Cc: linux-kernel@vger.kernel.org, axboe@kernel.dk, snitzer@redhat.com, martin.petersen@oracle.com, david@fromorbit.com, xfs@oss.sgi.com, dm-devel@redhat.com, hch@lst.de Subject: Re: [dm-devel] [PATCH v2 1/3] block: add sysfs entry for discard_alignment Message-ID: <20120703143949.GE11272@redhat.com> References: <1341235225-27551-1-git-send-email-pbonzini@redhat.com> <1341235225-27551-2-git-send-email-pbonzini@redhat.com> <20120703023442.GB3586@redhat.com> <4FF2DCB1.2090704@redhat.com> <20120703140048.GC11272@redhat.com> <4FF2FFEE.4000401@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4FF2FFEE.4000401@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 03, 2012 at 04:21:34PM +0200, Paolo Bonzini wrote: [..] > > That raises an interesting question for patch3. If the discard is happening to > > a partition, shouldn't you be looking at partition discard_alignment > > instead of always looking at queue discard_alignment? > > Good point! Like this? This looks better. > > diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h > index ba43f40..3530764 100644 > --- a/include/linux/blkdev.h > +++ b/include/linux/blkdev.h > @@ -1125,6 +1125,16 @@ static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector > & (lim->discard_granularity - 1); > } > > +static inline int bdev_discard_alignment(struct block_device *bdev) > +{ > + struct request_queue *q = bdev_get_queue(bdev); > + > + if (bdev != bdev->bd_contains) > + return bdev->bd_part->discard_alignment; > + > + return q->limits.discard_alignment; > +} > + > static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) > { > if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1) > diff --git a/block/blk-lib.c b/block/blk-lib.c > index b2bde5c..77d8869 100644 > --- a/block/blk-lib.c > +++ b/block/blk-lib.c > @@ -58,7 +58,7 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector, > /* Zero-sector (unknown) and one-sector granularities are the same. */ > granularity = max(q->limits.discard_granularity >> 9, 1U); > mask = granularity - 1; > - alignment = (q->limits.discard_alignment >> 9) & mask; > + alignment = bdev_discard_alignment(bdev) >> 9; Why are you removing AND with mask operation? I don't see any AND operation being done in bdev_discard_alignment(). Thanks Vivek From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id q63Ee1p1098954 for ; Tue, 3 Jul 2012 09:40:01 -0500 Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by cuda.sgi.com with ESMTP id aTIlgDYdKH1AykZ4 for ; Tue, 03 Jul 2012 07:40:00 -0700 (PDT) Date: Tue, 3 Jul 2012 10:39:49 -0400 From: Vivek Goyal Subject: Re: [dm-devel] [PATCH v2 1/3] block: add sysfs entry for discard_alignment Message-ID: <20120703143949.GE11272@redhat.com> References: <1341235225-27551-1-git-send-email-pbonzini@redhat.com> <1341235225-27551-2-git-send-email-pbonzini@redhat.com> <20120703023442.GB3586@redhat.com> <4FF2DCB1.2090704@redhat.com> <20120703140048.GC11272@redhat.com> <4FF2FFEE.4000401@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <4FF2FFEE.4000401@redhat.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Paolo Bonzini Cc: axboe@kernel.dk, martin.petersen@oracle.com, snitzer@redhat.com, linux-kernel@vger.kernel.org, xfs@oss.sgi.com, dm-devel@redhat.com, hch@lst.de On Tue, Jul 03, 2012 at 04:21:34PM +0200, Paolo Bonzini wrote: [..] > > That raises an interesting question for patch3. If the discard is happening to > > a partition, shouldn't you be looking at partition discard_alignment > > instead of always looking at queue discard_alignment? > > Good point! Like this? This looks better. > > diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h > index ba43f40..3530764 100644 > --- a/include/linux/blkdev.h > +++ b/include/linux/blkdev.h > @@ -1125,6 +1125,16 @@ static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector > & (lim->discard_granularity - 1); > } > > +static inline int bdev_discard_alignment(struct block_device *bdev) > +{ > + struct request_queue *q = bdev_get_queue(bdev); > + > + if (bdev != bdev->bd_contains) > + return bdev->bd_part->discard_alignment; > + > + return q->limits.discard_alignment; > +} > + > static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) > { > if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1) > diff --git a/block/blk-lib.c b/block/blk-lib.c > index b2bde5c..77d8869 100644 > --- a/block/blk-lib.c > +++ b/block/blk-lib.c > @@ -58,7 +58,7 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector, > /* Zero-sector (unknown) and one-sector granularities are the same. */ > granularity = max(q->limits.discard_granularity >> 9, 1U); > mask = granularity - 1; > - alignment = (q->limits.discard_alignment >> 9) & mask; > + alignment = bdev_discard_alignment(bdev) >> 9; Why are you removing AND with mask operation? I don't see any AND operation being done in bdev_discard_alignment(). Thanks Vivek _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs