From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753059AbbDCBDa (ORCPT ); Thu, 2 Apr 2015 21:03:30 -0400 Received: from cn.fujitsu.com ([59.151.112.132]:43169 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751916AbbDCBDZ (ORCPT ); Thu, 2 Apr 2015 21:03:25 -0400 X-IronPort-AV: E=Sophos;i="5.04,848,1406563200"; d="scan'208";a="90130899" From: Gu Zheng To: CC: , , , Subject: [PATCH] md: fix md io stats accounting broken Date: Fri, 3 Apr 2015 08:44:47 +0800 Message-ID: <1428021887-18128-1-git-send-email-guz.fnst@cn.fujitsu.com> X-Mailer: git-send-email 1.7.7 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.167.226.100] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Simon reported the md io stats accounting issue: " I'm seeing "iostat -x -k 1" print this after a RAID1 rebuild on 4.0-rc5. It's not abnormal other than it's 3-disk, with one being SSD (sdc) and the other two being write-mostly: Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util sda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 sdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 sdc 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 md0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 345.00 0.00 0.00 0.00 0.00 100.00 md2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 58779.00 0.00 0.00 0.00 0.00 100.00 md1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 12.00 0.00 0.00 0.00 0.00 100.00 " The cause is commit "18c0b223cf9901727ef3b02da6711ac930b4e5d4" uses the generic_start_io_acct to account the disk stats rather than the open code, but it also introduced the increase to .in_flight[rw] which is needless to md. So we re-use the open code here to fix it. Reported-by: Simon Kirby Cc: 3.19 Signed-off-by: Gu Zheng --- drivers/md/md.c | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 717daad..e617878 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -249,6 +249,7 @@ static void md_make_request(struct request_queue *q, struct bio *bio) const int rw = bio_data_dir(bio); struct mddev *mddev = q->queuedata; unsigned int sectors; + int cpu; if (mddev == NULL || mddev->pers == NULL || !mddev->ready) { @@ -284,7 +285,10 @@ static void md_make_request(struct request_queue *q, struct bio *bio) sectors = bio_sectors(bio); mddev->pers->make_request(mddev, bio); - generic_start_io_acct(rw, sectors, &mddev->gendisk->part0); + cpu = part_stat_lock(); + part_stat_inc(cpu, &mddev->gendisk->part0, ios[rw]); + part_stat_add(cpu, &mddev->gendisk->part0, sectors[rw], sectors); + part_stat_unlock(); if (atomic_dec_and_test(&mddev->active_io) && mddev->suspended) wake_up(&mddev->sb_wait); -- 1.7.7