All of lore.kernel.org
 help / color / mirror / Atom feed
From: Nikanth Karthikesan <knikanth@suse.de>
To: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@infradead.org>,
	xfs-masters@oss.sgi.com, xfs@oss.sgi.com,
	Jens Axboe <jens.axboe@oracle.com>
Subject: Re: [xfs-masters] [RESEND][PATCH 6/7] xfs: Remove code handling bio_alloc failure with __GFP_WAIT
Date: Mon, 20 Apr 2009 13:53:35 +0530	[thread overview]
Message-ID: <200904201353.35858.knikanth@suse.de> (raw)
In-Reply-To: <20090420010237.GF16929@discord.disaster>

On Monday 20 April 2009 06:32:37 Dave Chinner wrote:
> On Wed, Apr 15, 2009 at 04:09:30PM +0530, Nikanth Karthikesan wrote:
> > Resending as I accidentally missed Jens earlier.
> >
> > Jens, can you merge this as well.
> >
> > Thanks
> > Nikanth
> >
> > Remove code handling bio_alloc failure with __GFP_WAIT.
> > GFP_NOIO implies __GFP_WAIT.
>
> Not sure that is right. The intent of the code is that if we can't
> get a large bio immediately, try a smaller one which is more likely
> to succeed when we are under memory pressure. i.e. we will get IO
> moving faster than if we waited for a maximally sized biovec to be
> allocated.
>
> IOWs, I don't think __GFP_WAIT is implied by this code, regardless
> of what GFP_NOIO actually means now. The same code fragment can be
> found in NILFS, and it uses GFP_NOWAIT, not GFP_NOIO. I suspect that
> this is what this XFS code should be changed to use to retain the
> original intent of the code....
>

Yes, if that is the intent, it needs to be changed as GFP_NOWAIT. Otherwise 
the first attempt to get a larger bio itself would return only after it 
succeeds, which makes the logic useless.

Thanks
Nikanth

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

  reply	other threads:[~2009-04-20  8:35 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-04-15 10:39 [RESEND][PATCH 6/7] xfs: Remove code handling bio_alloc failure with __GFP_WAIT Nikanth Karthikesan
2009-04-20  1:02 ` [xfs-masters] " Dave Chinner
2009-04-20  8:23   ` Nikanth Karthikesan [this message]
2009-04-22  6:45   ` [PATCH] xfs: fix xfs_alloc_ioend_bio code to try and get atleast a smaller bio Nikanth Karthikesan

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=200904201353.35858.knikanth@suse.de \
    --to=knikanth@suse.de \
    --cc=david@fromorbit.com \
    --cc=hch@infradead.org \
    --cc=jens.axboe@oracle.com \
    --cc=xfs-masters@oss.sgi.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.