Commit 966dbde2 authored Oct 31, 2011 by Mel Gorman Committed by Linus Torvalds Oct 31, 2011

ext4: warn if direct reclaim tries to writeback pages



Direct reclaim should never writeback pages.  Warn if an attempt is made.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Alex Elder <aelder@sgi.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 94054fa3

fs/ext4/inode.c

+5 −1

Original line number	Original line	Diff line number	Diff line
	@@ -1811,8 +1811,12 @@ static int ext4_writepage(struct page *page,
	* We don't want to do block allocation, so redirty		* We don't want to do block allocation, so redirty
	* the page and return. We may reach here when we do		* the page and return. We may reach here when we do
	* a journal commit via journal_submit_inode_data_buffers.		* a journal commit via journal_submit_inode_data_buffers.
	* We can also reach here via shrink_page_list		* We can also reach here via shrink_page_list but it
			* should never be for direct reclaim so warn if that
			* happens
	*/		*/
			WARN_ON_ONCE((current->flags & (PF_MEMALLOC\|PF_KSWAPD)) ==
			PF_MEMALLOC);
	goto redirty_page;		goto redirty_page;
	}		}
	if (commit_write)		if (commit_write)