From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-Path: Sender: Tejun Heo Date: Tue, 14 Nov 2017 13:03:26 -0800 From: Tejun Heo To: Shaohua Li Cc: linux-block@vger.kernel.org, Jens Axboe , Kernel-team@fb.com Subject: Re: [PATCH] blkcg: correctly update stat Message-ID: <20171114210326.GS983427@devbig577.frc2.facebook.com> References: <2fefc7364715a5c7d928fd02e4edeb7f80633c7f.1510682654.git.shli@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <2fefc7364715a5c7d928fd02e4edeb7f80633c7f.1510682654.git.shli@fb.com> List-ID: On Tue, Nov 14, 2017 at 10:05:07AM -0800, Shaohua Li wrote: > blkcg_bio_issue_check() checks throtl for stat update, which isn't good > because the bio could be splitted into small bios, the samll bios go > into blkcg_bio_issue_check again and we update stat for the small bios, > so we the stat is double charged. To fix this, we only update stat if > the bio doesn't have BIO_THROTTLED flag. The fix will update stat ahead > of bio skips from blk-throttle, but eventually the stat is correct. > > This patch is on top of patch: > https://marc.info/?l=linux-block&m=151060860608914&w=2 > > Cc: Tejun Heo > Signed-off-by: Shaohua Li Acked-by: Tejun Heo Thanks. -- tejun