---

yaml
---
r: 115834
b: refs/heads/master
c: 62695a8
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 71088785c6bc68fddb450063d57b1bd1c78e0ea1
+refs/heads/master: 62695a84eb8f2e718bf4dfb21700afaa7a08e0ea

trunk/include/linux/migrate.h

@@ -7,7 +7,6 @@
 typedef struct page *new_page_t(struct page *, unsigned long private, int **);
 
 #ifdef CONFIG_MIGRATION
-extern int isolate_lru_page(struct page *p, struct list_head *pagelist);
 extern int putback_lru_pages(struct list_head *l);
 extern int migrate_page(struct address_space *,
 			struct page *, struct page *);
@@ -21,8 +20,6 @@ extern int migrate_vmas(struct mm_struct *mm,
 		const nodemask_t *from, const nodemask_t *to,
 		unsigned long flags);
 #else
-static inline int isolate_lru_page(struct page *p, struct list_head *list)
-					{ return -ENOSYS; }
 static inline int putback_lru_pages(struct list_head *l) { return 0; }
 static inline int migrate_pages(struct list_head *l, new_page_t x,
 		unsigned long private) { return -ENOSYS; }

trunk/mm/internal.h

@@ -39,6 +39,8 @@ static inline void __put_page(struct page *page)
 	atomic_dec(&page->_count);
 }
 
+extern int isolate_lru_page(struct page *page);
+
 extern void __free_pages_bootmem(struct page *page, unsigned int order);
 
 /*

trunk/mm/memory_hotplug.c

@@ -658,8 +658,9 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
 		 * We can skip free pages. And we can only deal with pages on
 		 * LRU.
 		 */
-		ret = isolate_lru_page(page, &source);
+		ret = isolate_lru_page(page);
 		if (!ret) { /* Success */
+			list_add_tail(&page->lru, &source);
 			move_pages--;
 		} else {
 			/* Becasue we don't have big zone->lock. we should

trunk/mm/mempolicy.c

@@ -93,6 +93,8 @@
 #include <asm/tlbflush.h>
 #include <asm/uaccess.h>
 
+#include "internal.h"
+
 /* Internal flags */
 #define MPOL_MF_DISCONTIG_OK (MPOL_MF_INTERNAL << 0)	/* Skip checks for continuous vmas */
 #define MPOL_MF_INVERT (MPOL_MF_INTERNAL << 1)		/* Invert check for nodemask */
@@ -762,8 +764,11 @@ static void migrate_page_add(struct page *page, struct list_head *pagelist,
 	/*
 	 * Avoid migrating a page that is shared with others.
 	 */
-	if ((flags & MPOL_MF_MOVE_ALL) || page_mapcount(page) == 1)
-		isolate_lru_page(page, pagelist);
+	if ((flags & MPOL_MF_MOVE_ALL) || page_mapcount(page) == 1) {
+		if (!isolate_lru_page(page)) {
+			list_add_tail(&page->lru, pagelist);
+		}
+	}
 }
 
 static struct page *new_node_page(struct page *page, unsigned long node, int **x)

trunk/mm/migrate.c

@@ -36,36 +36,6 @@
 
 #define lru_to_page(_head) (list_entry((_head)->prev, struct page, lru))
 
-/*
- * Isolate one page from the LRU lists. If successful put it onto
- * the indicated list with elevated page count.
- *
- * Result:
- *  -EBUSY: page not on LRU list
- *  0: page removed from LRU list and added to the specified list.
- */
-int isolate_lru_page(struct page *page, struct list_head *pagelist)
-{
-	int ret = -EBUSY;
-
-	if (PageLRU(page)) {
-		struct zone *zone = page_zone(page);
-
-		spin_lock_irq(&zone->lru_lock);
-		if (PageLRU(page) && get_page_unless_zero(page)) {
-			ret = 0;
-			ClearPageLRU(page);
-			if (PageActive(page))
-				del_page_from_active_list(zone, page);
-			else
-				del_page_from_inactive_list(zone, page);
-			list_add_tail(&page->lru, pagelist);
-		}
-		spin_unlock_irq(&zone->lru_lock);
-	}
-	return ret;
-}
-
 /*
  * migrate_prep() needs to be called before we start compiling a list of pages
  * to be migrated using isolate_lru_page().
@@ -914,7 +884,9 @@ static int do_move_pages(struct mm_struct *mm, struct page_to_node *pm,
 				!migrate_all)
 			goto put_and_set;
 
-		err = isolate_lru_page(page, &pagelist);
+		err = isolate_lru_page(page);
+		if (!err)
+			list_add_tail(&page->lru, &pagelist);
 put_and_set:
 		/*
 		 * Either remove the duplicate refcount from

trunk/mm/vmscan.c

@@ -844,6 +844,51 @@ static unsigned long clear_active_flags(struct list_head *page_list)
 	return nr_active;
 }
 
+/**
+ * isolate_lru_page - tries to isolate a page from its LRU list
+ * @page: page to isolate from its LRU list
+ *
+ * Isolates a @page from an LRU list, clears PageLRU and adjusts the
+ * vmstat statistic corresponding to whatever LRU list the page was on.
+ *
+ * Returns 0 if the page was removed from an LRU list.
+ * Returns -EBUSY if the page was not on an LRU list.
+ *
+ * The returned page will have PageLRU() cleared.  If it was found on
+ * the active list, it will have PageActive set.  That flag may need
+ * to be cleared by the caller before letting the page go.
+ *
+ * The vmstat statistic corresponding to the list on which the page was
+ * found will be decremented.
+ *
+ * Restrictions:
+ * (1) Must be called with an elevated refcount on the page. This is a
+ *     fundamentnal difference from isolate_lru_pages (which is called
+ *     without a stable reference).
+ * (2) the lru_lock must not be held.
+ * (3) interrupts must be enabled.
+ */
+int isolate_lru_page(struct page *page)
+{
+	int ret = -EBUSY;
+
+	if (PageLRU(page)) {
+		struct zone *zone = page_zone(page);
+
+		spin_lock_irq(&zone->lru_lock);
+		if (PageLRU(page) && get_page_unless_zero(page)) {
+			ret = 0;
+			ClearPageLRU(page);
+			if (PageActive(page))
+				del_page_from_active_list(zone, page);
+			else
+				del_page_from_inactive_list(zone, page);
+		}
+		spin_unlock_irq(&zone->lru_lock);
+	}
+	return ret;
+}
+
 /*
  * shrink_inactive_list() is a helper for shrink_zone().  It returns the number
  * of reclaimed pages