[PATCH 3/6] writeback: kupdate writeback shall not stop when more io is possible

[Wu Fengguang <fengguang.wu@intel.com>]

[-- Attachment #1: writeback-more-io.patch --]
[-- Type: text/plain, Size: 1190 bytes --]

Fix the kupdate case, which disregards wbc.more_io and stop writeback
prematurely even when there are more inodes to be synced.

wbc.more_io should always be respected.

Also remove the pages_skipped check. It will set when some page(s) of some
inode(s) cannot be written for now. Such inodes will be delayed for a while.
This variable has nothing to do with whether there are other writeable inodes.

CC: Jan Kara <jack@suse.cz>
CC: Dave Chinner <david@fromorbit.com>
CC: Jens Axboe <jens.axboe@oracle.com>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl> 
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
---
 fs/fs-writeback.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- linux.orig/fs/fs-writeback.c	2009-09-23 18:13:36.000000000 +0800
+++ linux/fs/fs-writeback.c	2009-09-23 18:33:17.000000000 +0800
@@ -756,8 +756,8 @@ static long wb_writeback(struct bdi_writ
 		/*
 		 * If we ran out of stuff to write, bail unless more_io got set
 		 */
-		if (wbc.nr_to_write > 0 || wbc.pages_skipped > 0) {
-			if (wbc.more_io && !wbc.for_kupdate) {
+		if (wbc.nr_to_write > 0) {
+			if (wbc.more_io) {
 				if (wbc.nr_to_write < MAX_WRITEBACK_PAGES)
 					continue;
 				/*