linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@infradead.org>
To: Mel Gorman <mgorman@suse.de>
Cc: Linux-MM <linux-mm@kvack.org>, Rik van Riel <riel@redhat.com>,
	Jan Kara <jack@suse.cz>, LKML <linux-kernel@vger.kernel.org>,
	XFS <xfs@oss.sgi.com>, Christoph Hellwig <hch@infradead.org>,
	Minchan Kim <minchan.kim@gmail.com>,
	Wu Fengguang <fengguang.wu@intel.com>,
	Johannes Weiner <jweiner@redhat.com>
Subject: Re: [PATCH 2/8] xfs: Warn if direct reclaim tries to writeback pages
Date: Sun, 24 Jul 2011 07:32:00 -0400	[thread overview]
Message-ID: <20110724113200.GA26332@infradead.org> (raw)
In-Reply-To: <1311265730-5324-3-git-send-email-mgorman@suse.de>

On Thu, Jul 21, 2011 at 05:28:44PM +0100, Mel Gorman wrote:
> --- a/fs/xfs/linux-2.6/xfs_aops.c
> +++ b/fs/xfs/linux-2.6/xfs_aops.c
> @@ -930,12 +930,13 @@ xfs_vm_writepage(
>  	 * random callers for direct reclaim or memcg reclaim.  We explicitly
>  	 * allow reclaim from kswapd as the stack usage there is relatively low.
>  	 *
> -	 * This should really be done by the core VM, but until that happens
> -	 * filesystems like XFS, btrfs and ext4 have to take care of this
> -	 * by themselves.
> +	 * This should never happen except in the case of a VM regression so
> +	 * warn about it.
>  	 */
> -	if ((current->flags & (PF_MEMALLOC|PF_KSWAPD)) == PF_MEMALLOC)
> +	if ((current->flags & (PF_MEMALLOC|PF_KSWAPD)) == PF_MEMALLOC) {
> +		WARN_ON_ONCE(1);
>  		goto redirty;

The nicer way to write this is

	if (WARN_ON(current->flags & (PF_MEMALLOC|PF_KSWAPD)) == PF_MEMALLOC)
		goto redirty;

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  reply	other threads:[~2011-07-24 11:32 UTC|newest]

Thread overview: 43+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-07-21 16:28 [RFC PATCH 0/8] Reduce filesystem writeback from page reclaim v2 Mel Gorman
2011-07-21 16:28 ` [PATCH 1/8] mm: vmscan: Do not writeback filesystem pages in direct reclaim Mel Gorman
2011-07-31 15:06   ` Minchan Kim
2011-08-02 11:21     ` Mel Gorman
2011-07-21 16:28 ` [PATCH 2/8] xfs: Warn if direct reclaim tries to writeback pages Mel Gorman
2011-07-24 11:32   ` Christoph Hellwig [this message]
2011-07-25  8:19     ` Mel Gorman
2011-07-21 16:28 ` [PATCH 3/8] ext4: " Mel Gorman
2011-08-03 10:58   ` Johannes Weiner
2011-08-03 11:06     ` Johannes Weiner
2011-08-03 13:44       ` Mel Gorman
2011-08-03 14:00         ` Johannes Weiner
2011-08-03 14:18           ` Christoph Hellwig
2011-08-03 14:35           ` Mel Gorman
2011-07-21 16:28 ` [PATCH 4/8] btrfs: " Mel Gorman
2011-08-03 11:10   ` Johannes Weiner
2011-08-03 13:45     ` Mel Gorman
2011-07-21 16:28 ` [PATCH 5/8] mm: vmscan: Do not writeback filesystem pages in kswapd except in high priority Mel Gorman
2011-07-31 15:11   ` Minchan Kim
2011-07-21 16:28 ` [PATCH 6/8] mm: vmscan: Throttle reclaim if encountering too many dirty pages under writeback Mel Gorman
2011-07-31 15:17   ` Minchan Kim
2011-08-03 11:19   ` Johannes Weiner
2011-08-03 13:56     ` Mel Gorman
2011-07-21 16:28 ` [PATCH 7/8] mm: vmscan: Immediately reclaim end-of-LRU dirty pages when writeback completes Mel Gorman
2011-07-22 12:53   ` Peter Zijlstra
2011-07-22 13:23     ` Mel Gorman
2011-07-31 15:24       ` Minchan Kim
2011-08-02 11:25         ` Mel Gorman
2011-08-03 11:26   ` Johannes Weiner
2011-08-03 13:57     ` Mel Gorman
2011-07-21 16:28 ` [PATCH 8/8] mm: vmscan: Do not writeback filesystem pages from kswapd Mel Gorman
2011-07-22 12:57   ` Peter Zijlstra
2011-07-22 13:31     ` Mel Gorman
2011-08-03 11:37   ` Johannes Weiner
2011-08-03 13:58     ` Mel Gorman
2011-07-26 11:20 ` [RFC PATCH 0/8] Reduce filesystem writeback from page reclaim v2 Dave Chinner
2011-07-27  4:32 ` Minchan Kim
2011-07-27  7:37   ` Mel Gorman
2011-07-27 16:18 ` Minchan Kim
2011-07-28 11:38   ` Mel Gorman
2011-07-29  9:48     ` Minchan Kim
2011-07-29  9:50       ` Minchan Kim
2011-07-29 13:41         ` Andrew Lutomirski

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=20110724113200.GA26332@infradead.org \
    --to=hch@infradead.org \
    --cc=fengguang.wu@intel.com \
    --cc=jack@suse.cz \
    --cc=jweiner@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mgorman@suse.de \
    --cc=minchan.kim@gmail.com \
    --cc=riel@redhat.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;
as well as URLs for NNTP newsgroup(s).