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-rw-r--r--mm/vmscan.c71
1 files changed, 30 insertions, 41 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c
index bf903b2d198f..827bf674577a 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -586,7 +586,7 @@ static inline void move_to_lru(struct page *page)
586} 586}
587 587
588/* 588/*
589 * Add isolated pages on the list back to the LRU 589 * Add isolated pages on the list back to the LRU.
590 * 590 *
591 * returns the number of pages put back. 591 * returns the number of pages put back.
592 */ 592 */
@@ -760,46 +760,33 @@ next:
760 return nr_failed + retry; 760 return nr_failed + retry;
761} 761}
762 762
763static void lru_add_drain_per_cpu(void *dummy)
764{
765 lru_add_drain();
766}
767
768/* 763/*
769 * Isolate one page from the LRU lists and put it on the 764 * Isolate one page from the LRU lists and put it on the
770 * indicated list. Do necessary cache draining if the 765 * indicated list with elevated refcount.
771 * page is not on the LRU lists yet.
772 * 766 *
773 * Result: 767 * Result:
774 * 0 = page not on LRU list 768 * 0 = page not on LRU list
775 * 1 = page removed from LRU list and added to the specified list. 769 * 1 = page removed from LRU list and added to the specified list.
776 * -ENOENT = page is being freed elsewhere.
777 */ 770 */
778int isolate_lru_page(struct page *page) 771int isolate_lru_page(struct page *page)
779{ 772{
780 int rc = 0; 773 int ret = 0;
781 struct zone *zone = page_zone(page);
782 774
783redo: 775 if (PageLRU(page)) {
784 spin_lock_irq(&zone->lru_lock); 776 struct zone *zone = page_zone(page);
785 rc = __isolate_lru_page(page); 777 spin_lock_irq(&zone->lru_lock);
786 if (rc == 1) { 778 if (TestClearPageLRU(page)) {
787 if (PageActive(page)) 779 ret = 1;
788 del_page_from_active_list(zone, page); 780 get_page(page);
789 else 781 if (PageActive(page))
790 del_page_from_inactive_list(zone, page); 782 del_page_from_active_list(zone, page);
791 } 783 else
792 spin_unlock_irq(&zone->lru_lock); 784 del_page_from_inactive_list(zone, page);
793 if (rc == 0) { 785 }
794 /* 786 spin_unlock_irq(&zone->lru_lock);
795 * Maybe this page is still waiting for a cpu to drain it
796 * from one of the lru lists?
797 */
798 rc = schedule_on_each_cpu(lru_add_drain_per_cpu, NULL);
799 if (rc == 0 && PageLRU(page))
800 goto redo;
801 } 787 }
802 return rc; 788
789 return ret;
803} 790}
804#endif 791#endif
805 792
@@ -831,18 +818,20 @@ static int isolate_lru_pages(int nr_to_scan, struct list_head *src,
831 page = lru_to_page(src); 818 page = lru_to_page(src);
832 prefetchw_prev_lru_page(page, src, flags); 819 prefetchw_prev_lru_page(page, src, flags);
833 820
834 switch (__isolate_lru_page(page)) { 821 if (!TestClearPageLRU(page))
835 case 1:
836 /* Succeeded to isolate page */
837 list_move(&page->lru, dst);
838 nr_taken++;
839 break;
840 case -ENOENT:
841 /* Not possible to isolate */
842 list_move(&page->lru, src);
843 break;
844 default:
845 BUG(); 822 BUG();
823 list_del(&page->lru);
824 if (get_page_testone(page)) {
825 /*
826 * It is being freed elsewhere
827 */
828 __put_page(page);
829 SetPageLRU(page);
830 list_add(&page->lru, src);
831 continue;
832 } else {
833 list_add(&page->lru, dst);
834 nr_taken++;
846 } 835 }
847 } 836 }
848 837