From: Peter Zijlstra <a.p.zijlstra@chello.nl>

Abstract the reclaimable condition for a page and use that in try_to_evict and
rotate_reclaimable_page. Also take out the knowledge of the rotation itself.

API:

is the page suitable for reclaim

	int __page_replace_reclaimable(struct page *);

rotate the page to the candidate end of the page scanner 
(when suitable for reclaim)

	void __page_replace_rotate_reclaimable(struct zone *, struct page *);

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
 
 include/linux/mm_lru_policy.h   |    8 ++++++++
 include/linux/mm_page_replace.h |    1 +
 mm/swap.c                       |    8 +-------
 3 files changed, 10 insertions(+), 7 deletions(-)

Index: linux-2.6-uml/include/linux/mm_lru_policy.h
===================================================================
--- linux-2.6-uml.orig/include/linux/mm_lru_policy.h	2006-02-23 22:02:15.000000000 +0100
+++ linux-2.6-uml/include/linux/mm_lru_policy.h	2006-02-23 22:02:17.000000000 +0100
@@ -48,5 +48,13 @@ static inline void page_replace_remove(s
 	}
 }
 
+static inline void __page_replace_rotate_reclaimable(struct zone *zone, struct page *page)
+{
+	if (PageLRU(page) && !PageActive(page)) {
+		list_move_tail(&page->lru, &zone->inactive_list);
+		inc_page_state(pgrotated);
+	}
+}
+
 #endif /* __KERNEL__ */
 #endif /* _LINUX_MM_LRU_POLICY_H */
Index: linux-2.6-uml/include/linux/mm_page_replace.h
===================================================================
--- linux-2.6-uml.orig/include/linux/mm_page_replace.h	2006-02-23 22:02:03.000000000 +0100
+++ linux-2.6-uml/include/linux/mm_page_replace.h	2006-02-23 22:02:17.000000000 +0100
@@ -58,6 +58,7 @@ extern void page_replace_candidates(stru
 extern void page_replace_reinsert(struct list_head *);
 extern void page_replace_reinsert_zone(struct zone *, struct list_head *, int);
 /* void page_replace_remove(struct zone *, struct page *); */
+/* void __page_replace_rotate_reclaimable(struct zone *, struct page *); */
 
 
 #ifdef CONFIG_MIGRATION
Index: linux-2.6-uml/mm/swap.c
===================================================================
--- linux-2.6-uml.orig/mm/swap.c	2006-02-23 22:02:03.000000000 +0100
+++ linux-2.6-uml/mm/swap.c	2006-02-23 22:02:17.000000000 +0100
@@ -78,18 +78,12 @@ int rotate_reclaimable_page(struct page 
 		return 1;
 	if (PageDirty(page))
 		return 1;
-	if (PageActive(page))
-		return 1;
 	if (!PageLRU(page))
 		return 1;
 
 	zone = page_zone(page);
 	spin_lock_irqsave(&zone->lru_lock, flags);
-	if (PageLRU(page) && !PageActive(page)) {
-		list_del(&page->lru);
-		list_add_tail(&page->lru, &zone->inactive_list);
-		inc_page_state(pgrotated);
-	}
+	__page_replace_rotate_reclaimable(zone, page);
 	if (!test_clear_page_writeback(page))
 		BUG();
 	spin_unlock_irqrestore(&zone->lru_lock, flags);