From: Mikulas Patocka Subject: [PATCH 1/3] dm: move dm_stats_account_io before generic_end_io_acct Date: Fri, 16 Nov 2018 01:04:17 +0100 Message-ID: <20181116000506.568964151@debian.vm> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline; filename=dm-stats-ordering.patch List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Mike Snitzer Cc: Jens Axboe , Christoph Hellwig , linux-block@vger.kernel.org, dm-devel@redhat.com, Mikulas Patocka , "Alasdair G. Kergon" List-Id: dm-devel.ids Make sure that the statistics are not updated while the device is suspended. So, we move statistics update before generic_end_io_acct. Signed-off-by: Mikulas Patocka --- drivers/md/dm.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) Index: linux-dm/drivers/md/dm.c =================================================================== --- linux-dm.orig/drivers/md/dm.c 2018-11-15 21:56:36.000000000 +0100 +++ linux-dm/drivers/md/dm.c 2018-11-15 21:56:36.000000000 +0100 @@ -674,6 +674,11 @@ static void end_io_acct(struct dm_io *io struct bio *bio = io->orig_bio; unsigned long duration = jiffies - io->start_time; + if (unlikely(dm_stats_used(&md->stats))) + dm_stats_account_io(&md->stats, bio_data_dir(bio), + bio->bi_iter.bi_sector, bio_sectors(bio), + true, duration, &io->stats_aux); + /* * make sure that atomic_dec in generic_end_io_acct is not reordered * with previous writes @@ -687,11 +692,6 @@ static void end_io_acct(struct dm_io *io */ smp_mb__after_atomic(); - if (unlikely(dm_stats_used(&md->stats))) - dm_stats_account_io(&md->stats, bio_data_dir(bio), - bio->bi_iter.bi_sector, bio_sectors(bio), - true, duration, &io->stats_aux); - /* nudge anyone waiting on suspend queue */ if (unlikely(waitqueue_active(&md->wait))) { if (!md_in_flight(md))