The caller of isolate_lru_pages specifically knows whether it wants to take either inactive or active pages. Currently we take the state of the LRU page at hand and use that to scan for matching pages in the order sized block. If that page is transiting we can scan for the wrong type. The caller knows what they want and should be telling us. Pass in the required active/inactive state and match against that.
Note, that now we pass the expected active state when scanning the active/inactive lists we may find missmatching target pages, pages which are in the process of changing state. This is no longer an error and we should simply ignore them. Signed-off-by: Andy Whitcroft <[EMAIL PROTECTED]> --- diff --git a/mm/vmscan.c b/mm/vmscan.c index f15ffcb..b878d54 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -663,12 +663,13 @@ static int __isolate_lru_page(struct page *page, int active) * @dst: The temp list to put pages on to. * @scanned: The number of pages that were scanned. * @order: The caller's attempted allocation order + * @active: The caller's trying to obtain active or inactive pages * * returns how many pages were moved onto [EMAIL PROTECTED] */ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, struct list_head *src, struct list_head *dst, - unsigned long *scanned, int order) + unsigned long *scanned, int order, int active) { unsigned long nr_taken = 0; unsigned long scan; @@ -678,7 +679,6 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, unsigned long pfn; unsigned long end_pfn; unsigned long page_pfn; - int active; int zone_id; page = lru_to_page(src); @@ -686,20 +686,16 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, VM_BUG_ON(!PageLRU(page)); - active = PageActive(page); switch (__isolate_lru_page(page, active)) { case 0: list_move(&page->lru, dst); nr_taken++; break; - case -EBUSY: - /* else it is being freed elsewhere */ + default: + /* page is being freed, or is a missmatch */ list_move(&page->lru, src); continue; - - default: - BUG(); } if (!order) @@ -768,8 +764,8 @@ static unsigned long shrink_inactive_list(unsigned long max_scan, unsigned long nr_freed; nr_taken = isolate_lru_pages(sc->swap_cluster_max, - &zone->inactive_list, - &page_list, &nr_scan, sc->order); + &zone->inactive_list, + &page_list, &nr_scan, sc->order, 0); __mod_zone_page_state(zone, NR_INACTIVE, -nr_taken); zone->pages_scanned += nr_scan; zone->total_scanned += nr_scan; @@ -916,7 +912,7 @@ force_reclaim_mapped: lru_add_drain(); spin_lock_irq(&zone->lru_lock); pgmoved = isolate_lru_pages(nr_pages, &zone->active_list, - &l_hold, &pgscanned, sc->order); + &l_hold, &pgscanned, sc->order, 1); zone->pages_scanned += pgscanned; __mod_zone_page_state(zone, NR_ACTIVE, -pgmoved); spin_unlock_irq(&zone->lru_lock); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/