public inbox for linux-xfs@vger.kernel.org
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@infradead.org>
To: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@infradead.org>,
	chris.mason@oracle.com, xfs@oss.sgi.com
Subject: Re: [PATCH 3/5] xfs: convert ENOSPC inode flushing to use new syncd workqueue
Date: Fri, 4 Mar 2011 07:40:18 -0500	[thread overview]
Message-ID: <20110304124018.GA29062@infradead.org> (raw)
In-Reply-To: <20110303224105.GP15097@dastard>

On Fri, Mar 04, 2011 at 09:41:05AM +1100, Dave Chinner wrote:
> On Thu, Mar 03, 2011 at 10:34:10AM -0500, Christoph Hellwig wrote:
> > I still don't see any point in having the ENOSPC flushing moved to a
> > different context.
> 
> IIRC, stack usage has always been an issue, and we also call
> xfs_flush_inodes() with the XFS_IOLOCK held (from
> xfs_iomap_write_delay()) so the alternate context was used to avoid
> deadlocks. I don't think we have that deadlock problem now thanks to
> being able to combine SYNC_TRYLOCK | SYNC_WAIT flags, but I'm not
> sure we can ignore the stack issues.

Given that we wait for completion of the syncing in the caller moving it
to a different context does not help with any deadlocks.  It just makes
them impossible to detect using lockdep.

> I've also realised the work_pending() check is unnecessary, as is
> the lock, because queue_work() will only queue new work if the work
> item isn't already pending so there's no need to check it here.
> Hence all this actually needs to do is:
> 
> 	queue_work()
> 	flush_work_sync()

or in fact only use the writeback_inodes_sb_if_idle call you added
later.  That also causes writeback of data from the flusher threads.

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

  reply	other threads:[~2011-03-04 12:37 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-02-22 22:16 [RFC, PATCH 0/5] xfs: Reduce OOM kill problems under heavy load Dave Chinner
2011-02-22 22:16 ` [PATCH 1/5] xfs: introduce inode cluster buffer trylocks for xfs_iflush Dave Chinner
2011-03-03 15:55   ` Christoph Hellwig
2011-03-03 22:04     ` Dave Chinner
2011-02-22 22:16 ` [PATCH 2/5] xfs: introduce a xfssyncd workqueue Dave Chinner
2011-02-22 22:16 ` [PATCH 3/5] xfs: convert ENOSPC inode flushing to use new syncd workqueue Dave Chinner
2011-03-03 15:34   ` Christoph Hellwig
2011-03-03 22:41     ` Dave Chinner
2011-03-04 12:40       ` Christoph Hellwig [this message]
2011-02-22 22:16 ` [PATCH 4/5] xfs: introduce background inode reclaim work Dave Chinner
2011-03-03 15:36   ` Christoph Hellwig
2011-03-03 22:43     ` Dave Chinner
2011-02-22 22:16 ` [PATCH 5/5] xfs: kick inode writeback when low on memory Dave Chinner
2011-03-02  3:06   ` Dave Chinner
2011-03-02 14:12     ` Christoph Hellwig
2011-03-03  2:42       ` Dave Chinner
2011-03-03 15:48         ` Christoph Hellwig
2011-03-03 16:19           ` Christoph Hellwig
2011-03-09  5:46             ` Dave Chinner

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20110304124018.GA29062@infradead.org \
    --to=hch@infradead.org \
    --cc=chris.mason@oracle.com \
    --cc=david@fromorbit.com \
    --cc=xfs@oss.sgi.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox