From: Vivek Goyal Subject: [PATCH 3/3] ext3: Explicitly specify fsync dependency on journaling thread Date: Mon, 27 Jun 2011 16:17:44 -0400 Message-ID: <1309205864-13124-4-git-send-email-vgoyal@redhat.com> References: <1309205864-13124-1-git-send-email-vgoyal@redhat.com> Cc: vgoyal@redhat.com, khlebnikov@openvz.org, jmoyer@redhat.com To: linux-kernel@vger.kernel.org, jaxboe@fusionio.com, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:29044 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754153Ab1F0URt (ORCPT ); Mon, 27 Jun 2011 16:17:49 -0400 In-Reply-To: <1309205864-13124-1-git-send-email-vgoyal@redhat.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: Set/reset fsync dependency of fsync on journalling thread. This allows CFQ to dispatch IO from journalling thread in fsync's time slice. Otherwise, lots of cfq queue idling takes place if fsync is running in a separate cgroup and journalling thread is running in root group. Signed-off-by: Vivek Goyal --- fs/ext3/fsync.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/fs/ext3/fsync.c b/fs/ext3/fsync.c index 09b13bb..1e8de9c 100644 --- a/fs/ext3/fsync.c +++ b/fs/ext3/fsync.c @@ -82,7 +82,10 @@ int ext3_sync_file(struct file *file, int datasync) !journal_trans_will_send_data_barrier(journal, commit_tid)) needs_barrier = 1; log_start_commit(journal, commit_tid); + blk_set_depends_on_task(journal->j_dev->bd_disk->queue, + journal->j_task); ret = log_wait_commit(journal, commit_tid); + blk_reset_depends_on_task(journal->j_dev->bd_disk->queue); /* * In case we didn't commit a transaction, we have to flush -- 1.7.4.4