Subject: writeback: delay periodic work on wrap
Date: Fri Dec 16 19:19:16 CST 2011

This guarantees some break time on busy overwriters.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
---
 fs/ext4/inode.c     |    1 +
 mm/page-writeback.c |    1 +
 2 files changed, 2 insertions(+)

--- linux.orig/fs/ext4/inode.c	2011-12-16 19:17:04.000000000 +0800
+++ linux/fs/ext4/inode.c	2011-12-16 19:18:26.000000000 +0800
@@ -2966,6 +2966,7 @@ static int ext4_da_writepages(struct add
 			/*
 			 * There is no more writeout needed
 			 */
+			inode->dirtied_when = jiffies;
 			index = 0;
 			break;
 		}
--- linux.orig/mm/page-writeback.c	2011-12-16 19:13:15.000000000 +0800
+++ linux/mm/page-writeback.c	2011-12-16 19:57:14.000000000 +0800
@@ -856,6 +856,7 @@ int write_cache_pages(struct address_spa
 			      PAGECACHE_TAG_DIRTY,
 			      min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1);
 		if (nr_pages == 0) {
+			mapping->host->dirtied_when = jiffies;
 			done_index = 0;
 			break;
 		}