From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: Re: [PATCH] md: use REQ_NOIDLE flag in md_super_write() Date: Thu, 4 Aug 2011 14:26:39 +1000 Message-ID: <20110804142639.6484de94@notabene.brown> References: <1312387077-26617-1-git-send-email-namhyung@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1312387077-26617-1-git-send-email-namhyung@gmail.com> Sender: linux-raid-owner@vger.kernel.org To: Namhyung Kim Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-raid.ids On Thu, 4 Aug 2011 00:57:57 +0900 Namhyung Kim wrote: > Queue idling is used for the anticipation of immediate > sequencial I/O's but md_super_write() is a kind of one- > shot operation, coupled with md_super_wait(), so the > idling in this case will be just a waste of time. > > Specifying REQ_NOIDLE prevents it. Instead of adding > the flag to submit_bio() directly, use pre-defined > macro WRITE_FLUSH_FUA. > > Signed-off-by: Namhyung Kim > --- > drivers/md/md.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/drivers/md/md.c b/drivers/md/md.c > index d97a62534798..8650e9a0ce7c 100644 > --- a/drivers/md/md.c > +++ b/drivers/md/md.c > @@ -848,7 +848,7 @@ void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev, > bio->bi_end_io = super_written; > > atomic_inc(&mddev->pending_writes); > - submit_bio(REQ_WRITE | REQ_SYNC | REQ_FLUSH | REQ_FUA, bio); > + submit_bio(WRITE_FLUSH_FUA, bio); > } > > void md_super_wait(mddev_t *mddev) Applied, thanks. NeilBrown