Merge commit 'v2.6.28-rc2' into core/locking

Conflicts:
	arch/um/include/asm/system.h

1 files changed, 115 insertions, 57 deletions

diff --git a/mm/swap.c b/mm/swap.c
index 9e0cb3118079..2152e48a7b8f 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -31,11 +31,12 @@
 #include <linux/backing-dev.h>
 #include <linux/memcontrol.h>
 
+#include "internal.h"
+
 /* How many pages do we try to swap or page in/out together? */
 int page_cluster;
 
-static DEFINE_PER_CPU(struct pagevec, lru_add_pvecs);
-static DEFINE_PER_CPU(struct pagevec, lru_add_active_pvecs);
+static DEFINE_PER_CPU(struct pagevec[NR_LRU_LISTS], lru_add_pvecs);
 static DEFINE_PER_CPU(struct pagevec, lru_rotate_pvecs);
 
 /*
@@ -116,8 +117,9 @@ static void pagevec_move_tail(struct pagevec *pvec)
 			zone = pagezone;
 			spin_lock(&zone->lru_lock);
 		}
-		if (PageLRU(page) && !PageActive(page)) {
-			list_move_tail(&page->lru, &zone->inactive_list);
+		if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
+			int lru = page_is_file_cache(page);
+			list_move_tail(&page->lru, &zone->lru[lru].list);
 			pgmoved++;
 		}
 	}
@@ -136,7 +138,7 @@ static void pagevec_move_tail(struct pagevec *pvec)
 void  rotate_reclaimable_page(struct page *page)
 {
 	if (!PageLocked(page) && !PageDirty(page) && !PageActive(page) &&
-	    PageLRU(page)) {
+	    !PageUnevictable(page) && PageLRU(page)) {
 		struct pagevec *pvec;
 		unsigned long flags;
 
@@ -157,12 +159,19 @@ void activate_page(struct page *page)
 	struct zone *zone = page_zone(page);
 
 	spin_lock_irq(&zone->lru_lock);
-	if (PageLRU(page) && !PageActive(page)) {
-		del_page_from_inactive_list(zone, page);
+	if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
+		int file = page_is_file_cache(page);
+		int lru = LRU_BASE + file;
+		del_page_from_lru_list(zone, page, lru);
+
 		SetPageActive(page);
-		add_page_to_active_list(zone, page);
+		lru += LRU_ACTIVE;
+		add_page_to_lru_list(zone, page, lru);
 		__count_vm_event(PGACTIVATE);
-		mem_cgroup_move_lists(page, true);
+		mem_cgroup_move_lists(page, lru);
+
+		zone->recent_rotated[!!file]++;
+		zone->recent_scanned[!!file]++;
 	}
 	spin_unlock_irq(&zone->lru_lock);
 }
@@ -176,7 +185,8 @@ void activate_page(struct page *page)
  */
 void mark_page_accessed(struct page *page)
 {
-	if (!PageActive(page) && PageReferenced(page) && PageLRU(page)) {
+	if (!PageActive(page) && !PageUnevictable(page) &&
+			PageReferenced(page) && PageLRU(page)) {
 		activate_page(page);
 		ClearPageReferenced(page);
 	} else if (!PageReferenced(page)) {
@@ -186,28 +196,73 @@ void mark_page_accessed(struct page *page)
 
 EXPORT_SYMBOL(mark_page_accessed);
 
-/**
- * lru_cache_add: add a page to the page lists
- * @page: the page to add
- */
-void lru_cache_add(struct page *page)
+void __lru_cache_add(struct page *page, enum lru_list lru)
 {
-	struct pagevec *pvec = &get_cpu_var(lru_add_pvecs);
+	struct pagevec *pvec = &get_cpu_var(lru_add_pvecs)[lru];
 
 	page_cache_get(page);
 	if (!pagevec_add(pvec, page))
-		__pagevec_lru_add(pvec);
+		____pagevec_lru_add(pvec, lru);
 	put_cpu_var(lru_add_pvecs);
 }
 
-void lru_cache_add_active(struct page *page)
+/**
+ * lru_cache_add_lru - add a page to a page list
+ * @page: the page to be added to the LRU.
+ * @lru: the LRU list to which the page is added.
+ */
+void lru_cache_add_lru(struct page *page, enum lru_list lru)
 {
-	struct pagevec *pvec = &get_cpu_var(lru_add_active_pvecs);
+	if (PageActive(page)) {
+		VM_BUG_ON(PageUnevictable(page));
+		ClearPageActive(page);
+	} else if (PageUnevictable(page)) {
+		VM_BUG_ON(PageActive(page));
+		ClearPageUnevictable(page);
+	}
 
-	page_cache_get(page);
-	if (!pagevec_add(pvec, page))
-		__pagevec_lru_add_active(pvec);
-	put_cpu_var(lru_add_active_pvecs);
+	VM_BUG_ON(PageLRU(page) || PageActive(page) || PageUnevictable(page));
+	__lru_cache_add(page, lru);
+}
+
+/**
+ * add_page_to_unevictable_list - add a page to the unevictable list
+ * @page:  the page to be added to the unevictable list
+ *
+ * Add page directly to its zone's unevictable list.  To avoid races with
+ * tasks that might be making the page evictable, through eg. munlock,
+ * munmap or exit, while it's not on the lru, we want to add the page
+ * while it's locked or otherwise "invisible" to other tasks.  This is
+ * difficult to do when using the pagevec cache, so bypass that.
+ */
+void add_page_to_unevictable_list(struct page *page)
+{
+	struct zone *zone = page_zone(page);
+
+	spin_lock_irq(&zone->lru_lock);
+	SetPageUnevictable(page);
+	SetPageLRU(page);
+	add_page_to_lru_list(zone, page, LRU_UNEVICTABLE);
+	spin_unlock_irq(&zone->lru_lock);
+}
+
+/**
+ * lru_cache_add_active_or_unevictable
+ * @page:  the page to be added to LRU
+ * @vma:   vma in which page is mapped for determining reclaimability
+ *
+ * place @page on active or unevictable LRU list, depending on
+ * page_evictable().  Note that if the page is not evictable,
+ * it goes directly back onto it's zone's unevictable list.  It does
+ * NOT use a per cpu pagevec.
+ */
+void lru_cache_add_active_or_unevictable(struct page *page,
+					struct vm_area_struct *vma)
+{
+	if (page_evictable(page, vma))
+		lru_cache_add_lru(page, LRU_ACTIVE + page_is_file_cache(page));
+	else
+		add_page_to_unevictable_list(page);
 }
 
 /*
@@ -217,15 +272,15 @@ void lru_cache_add_active(struct page *page)
  */
 static void drain_cpu_pagevecs(int cpu)
 {
+	struct pagevec *pvecs = per_cpu(lru_add_pvecs, cpu);
 	struct pagevec *pvec;
+	int lru;
 
-	pvec = &per_cpu(lru_add_pvecs, cpu);
-	if (pagevec_count(pvec))
-		__pagevec_lru_add(pvec);
-
-	pvec = &per_cpu(lru_add_active_pvecs, cpu);
-	if (pagevec_count(pvec))
-		__pagevec_lru_add_active(pvec);
+	for_each_lru(lru) {
+		pvec = &pvecs[lru - LRU_BASE];
+		if (pagevec_count(pvec))
+			____pagevec_lru_add(pvec, lru);
+	}
 
 	pvec = &per_cpu(lru_rotate_pvecs, cpu);
 	if (pagevec_count(pvec)) {
@@ -244,7 +299,7 @@ void lru_add_drain(void)
 	put_cpu();
 }
 
-#ifdef CONFIG_NUMA
+#if defined(CONFIG_NUMA) || defined(CONFIG_UNEVICTABLE_LRU)
 static void lru_add_drain_per_cpu(struct work_struct *dummy)
 {
 	lru_add_drain();
@@ -308,6 +363,7 @@ void release_pages(struct page **pages, int nr, int cold)
 
 		if (PageLRU(page)) {
 			struct zone *pagezone = page_zone(page);
+
 			if (pagezone != zone) {
 				if (zone)
 					spin_unlock_irqrestore(&zone->lru_lock,
@@ -380,10 +436,11 @@ void __pagevec_release_nonlru(struct pagevec *pvec)
  * Add the passed pages to the LRU, then drop the caller's refcount
  * on them.  Reinitialises the caller's pagevec.
  */
-void __pagevec_lru_add(struct pagevec *pvec)
+void ____pagevec_lru_add(struct pagevec *pvec, enum lru_list lru)
 {
 	int i;
 	struct zone *zone = NULL;
+	VM_BUG_ON(is_unevictable_lru(lru));
 
 	for (i = 0; i < pagevec_count(pvec); i++) {
 		struct page *page = pvec->pages[i];
@@ -395,9 +452,13 @@ void __pagevec_lru_add(struct pagevec *pvec)
 			zone = pagezone;
 			spin_lock_irq(&zone->lru_lock);
 		}
+		VM_BUG_ON(PageActive(page));
+		VM_BUG_ON(PageUnevictable(page));
 		VM_BUG_ON(PageLRU(page));
 		SetPageLRU(page);
-		add_page_to_inactive_list(zone, page);
+		if (is_active_lru(lru))
+			SetPageActive(page);
+		add_page_to_lru_list(zone, page, lru);
 	}
 	if (zone)
 		spin_unlock_irq(&zone->lru_lock);
@@ -405,48 +466,45 @@ void __pagevec_lru_add(struct pagevec *pvec)
 	pagevec_reinit(pvec);
 }
 
-EXPORT_SYMBOL(__pagevec_lru_add);
+EXPORT_SYMBOL(____pagevec_lru_add);
 
-void __pagevec_lru_add_active(struct pagevec *pvec)
+/*
+ * Try to drop buffers from the pages in a pagevec
+ */
+void pagevec_strip(struct pagevec *pvec)
 {
 	int i;
-	struct zone *zone = NULL;
 
 	for (i = 0; i < pagevec_count(pvec); i++) {
 		struct page *page = pvec->pages[i];
-		struct zone *pagezone = page_zone(page);
 
-		if (pagezone != zone) {
-			if (zone)
-				spin_unlock_irq(&zone->lru_lock);
-			zone = pagezone;
-			spin_lock_irq(&zone->lru_lock);
+		if (PagePrivate(page) && trylock_page(page)) {
+			if (PagePrivate(page))
+				try_to_release_page(page, 0);
+			unlock_page(page);
 		}
-		VM_BUG_ON(PageLRU(page));
-		SetPageLRU(page);
-		VM_BUG_ON(PageActive(page));
-		SetPageActive(page);
-		add_page_to_active_list(zone, page);
 	}
-	if (zone)
-		spin_unlock_irq(&zone->lru_lock);
-	release_pages(pvec->pages, pvec->nr, pvec->cold);
-	pagevec_reinit(pvec);
 }
 
-/*
- * Try to drop buffers from the pages in a pagevec
+/**
+ * pagevec_swap_free - try to free swap space from the pages in a pagevec
+ * @pvec: pagevec with swapcache pages to free the swap space of
+ *
+ * The caller needs to hold an extra reference to each page and
+ * not hold the page lock on the pages.  This function uses a
+ * trylock on the page lock so it may not always free the swap
+ * space associated with a page.
  */
-void pagevec_strip(struct pagevec *pvec)
+void pagevec_swap_free(struct pagevec *pvec)
 {
 	int i;
 
 	for (i = 0; i < pagevec_count(pvec); i++) {
 		struct page *page = pvec->pages[i];
 
-		if (PagePrivate(page) && trylock_page(page)) {
-			if (PagePrivate(page))
-				try_to_release_page(page, 0);
+		if (PageSwapCache(page) && trylock_page(page)) {
+			if (PageSwapCache(page))
+				remove_exclusive_swap_page_ref(page);
 			unlock_page(page);
 		}
 	}