From 9d4e63229159a9e982774b04f1b3a5d651d62ab4 Mon Sep 17 00:00:00 2001
From: Arne Fitzenreiter <arne_f@ipfire.org>
Date: Sat, 16 Oct 2010 12:12:31 +0200
Subject: [PATCH] Add a patch for speedup cache writeback.

---
 lfs/linux                                     |  3 ++
 lfs/linux-pae                                 |  3 ++
 ...vmscan_remove_wait_on_page_writeback.patch | 37 +++++++++++++++++++
 3 files changed, 43 insertions(+)
 create mode 100644 src/patches/linux-2.6-vmscan_remove_wait_on_page_writeback.patch

diff --git a/lfs/linux b/lfs/linux
index 4e465bbccc..2955ac6ccb 100644
--- a/lfs/linux
+++ b/lfs/linux
@@ -131,6 +131,9 @@ endif
 	# Reiser4 (don't check if fail (some patches are already in xen patchset)
 	-cd $(DIR_APP) && bzcat $(DIR_DL)/reiser4-for-2.6.32.patch.bz2 | patch -Np1
 
+	# Fix lag's at cache access (eg. quit of mc)
+	cd $(DIR_APP) && patch -Np1 < $(DIR_SRC)/src/patches/linux-2.6-vmscan_remove_wait_on_page_writeback.patch
+
 	# ipp2p 0.8.2-pomng
 	cd $(DIR_APP) && patch -Np1 < $(DIR_SRC)/src/patches/linux-2.6.32.8-ipp2p-0.8.2-pomng.patch
 
diff --git a/lfs/linux-pae b/lfs/linux-pae
index cbaeefe333..d71a0cf944 100644
--- a/lfs/linux-pae
+++ b/lfs/linux-pae
@@ -23,6 +23,9 @@
 ###############################################################################
 
 include Config
+
+VER	   = kernel
+
 include linux
 
 PROG	   = linux-pae
diff --git a/src/patches/linux-2.6-vmscan_remove_wait_on_page_writeback.patch b/src/patches/linux-2.6-vmscan_remove_wait_on_page_writeback.patch
new file mode 100644
index 0000000000..02e9cd1799
--- /dev/null
+++ b/src/patches/linux-2.6-vmscan_remove_wait_on_page_writeback.patch
@@ -0,0 +1,37 @@
+--- linux-next.orig/mm/vmscan.c	2010-07-28 16:22:21.000000000 +0800
++++ linux-next/mm/vmscan.c	2010-07-28 16:23:35.000000000 +0800
+@@ -324,8 +324,7 @@ typedef enum {
+  * pageout is called by shrink_page_list() for each dirty page.
+  * Calls ->writepage().
+  */
+-static pageout_t pageout(struct page *page, struct address_space *mapping,
+-						enum pageout_io sync_writeback)
++static pageout_t pageout(struct page *page, struct address_space *mapping)
+ {
+ 	/*
+ 	 * If the page is dirty, only perform writeback if that write
+@@ -384,14 +383,6 @@ static pageout_t pageout(struct page *pa
+ 			return PAGE_ACTIVATE;
+ 		}
+ 
+-		/*
+-		 * Wait on writeback if requested to. This happens when
+-		 * direct reclaiming a large contiguous area and the
+-		 * first attempt to free a range of pages fails.
+-		 */
+-		if (PageWriteback(page) && sync_writeback == PAGEOUT_IO_SYNC)
+-			wait_on_page_writeback(page);
+-
+ 		if (!PageWriteback(page)) {
+ 			/* synchronous write or broken a_ops? */
+ 			ClearPageReclaim(page);
+@@ -727,7 +718,7 @@ static unsigned long shrink_page_list(st
+ 				goto keep_locked;
+ 
+ 			/* Page is dirty, try to write it out here */
+-			switch (pageout(page, mapping, sync_writeback)) {
++			switch (pageout(page, mapping)) {
+ 			case PAGE_KEEP:
+ 				goto keep_locked;
+ 			case PAGE_ACTIVATE:
+
-- 
2.39.2