linux-ext4 - [PATCH 2/3] ext4: Explicitly specify fsync dependency on journaling thread

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 27 Jun 2011 16:17:43 -0400
From:	Vivek Goyal <vgoyal@...hat.com>
To:	linux-kernel@...r.kernel.org, jaxboe@...ionio.com,
	linux-fsdevel@...r.kernel.org, linux-ext4@...r.kernel.org
Cc:	vgoyal@...hat.com, khlebnikov@...nvz.org, jmoyer@...hat.com
Subject: [PATCH 2/3] ext4: Explicitly specify fsync dependency on journaling thread

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 <vgoyal@...hat.com>
---
 fs/ext4/fsync.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c
index ce66d2f..8b16a90 100644
--- a/fs/ext4/fsync.c
+++ b/fs/ext4/fsync.c
@@ -216,7 +216,10 @@ int ext4_sync_file(struct file *file, int datasync)
 	    !jbd2_trans_will_send_data_barrier(journal, commit_tid))
 		needs_barrier = true;
 	jbd2_log_start_commit(journal, commit_tid);
+	blk_set_depends_on_task(journal->j_dev->bd_disk->queue,
+				journal->j_task);
 	ret = jbd2_log_wait_commit(journal, commit_tid);
+	blk_reset_depends_on_task(journal->j_dev->bd_disk->queue);
 	if (needs_barrier)
 		blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
  out:
-- 
1.7.4.4

--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html