From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wu Fengguang <fengguang.wu@intel.com>
Subject: [PATCH 32/45] writeback: update kupdate expire timestamp on each scan of b_io
Date: Wed, 07 Oct 2009 15:38:50 +0800
Message-ID: <20091007074905.265923767@intel.com>
References: <20091007073818.318088777@intel.com>
Cc: Theodore Tso <tytso@mit.edu>,
	Christoph Hellwig <hch@infradead.org>,
	Dave Chinner <david@fromorbit.com>,
	Chris Mason <chris.mason@oracle.com>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>,
	"Li Shaohua" <shaohua.li@intel.com>,
	"Myklebust Trond" <Trond.Myklebust@netapp.com>,
	"jens.axboe@oracle.com" <jens.axboe@oracle.com>,
	Jan Kara <jack@suse.cz>, Nick Piggin <npiggin@suse.de>,
	<linux-fsdevel@vger.kernel.org>,
	Wu Fengguang <fengguang.wu@intel.com>
To: Andrew Morton <akpm@linux-foundation.org>
Return-path: <linux-kernel-owner+glk-linux-kernel-3=40m.gmane.org-S934009AbZJGIB7@vger.kernel.org>
Cc: LKML <linux-kernel@vger.kernel.org>
Content-Disposition: inline; filename=writeback-moving-expired.patch
Sender: linux-kernel-owner@vger.kernel.org
List-Id: linux-fsdevel.vger.kernel.org

This prevents it to stuck with some very old but busy inodes,
and to give newer expired inodes a fair chance.

CC: Jan Kara <jack@suse.cz> 
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
---
 fs/fs-writeback.c |    3 +++
 1 file changed, 3 insertions(+)

--- linux.orig/fs/fs-writeback.c	2009-10-06 23:39:31.000000000 +0800
+++ linux/fs/fs-writeback.c	2009-10-06 23:39:32.000000000 +0800
@@ -829,6 +829,9 @@ static long wb_writeback(struct bdi_writ
 		args->nr_pages -= nr;
 		wrote += nr;
 
+		if (args->for_kupdate && list_empty(&wb->b_io))
+			oldest_jif = jiffies - expire_interval;
+
 		if (args->for_background && expire_interval &&
 		    ++fg_rounds && list_empty(&wb->b_io)) {
 			if (fg_rounds < 10)