diff options
| -rw-r--r-- | include/linux/mm.h | 19 | ||||
| -rw-r--r-- | mm/vmscan.c | 25 |
2 files changed, 22 insertions, 22 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 498ff8778fb..b12d5c76420 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -301,17 +301,20 @@ struct page { * Drop a ref, return true if the logical refcount fell to zero (the page has * no users) */ -#define put_page_testzero(p) \ - ({ \ - BUG_ON(atomic_read(&(p)->_count) == -1);\ - atomic_add_negative(-1, &(p)->_count); \ - }) +static inline int put_page_testzero(struct page *page) +{ + BUG_ON(atomic_read(&page->_count) == -1); + return atomic_add_negative(-1, &page->_count); +} /* - * Grab a ref, return true if the page previously had a logical refcount of - * zero. ie: returns true if we just grabbed an already-deemed-to-be-free page + * Try to grab a ref unless the page has a refcount of zero, return false if + * that is the case. */ -#define get_page_testone(p) atomic_inc_and_test(&(p)->_count) +static inline int get_page_unless_zero(struct page *page) +{ + return atomic_add_unless(&page->_count, 1, -1); +} #define set_page_count(p,v) atomic_set(&(p)->_count, (v) - 1) #define __put_page(p) atomic_dec(&(p)->_count) diff --git a/mm/vmscan.c b/mm/vmscan.c index 8e477b1a483..e21bab4deda 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1083,29 +1083,26 @@ static int isolate_lru_pages(int nr_to_scan, struct list_head *src, int scan = 0; while (scan++ < nr_to_scan && !list_empty(src)) { + struct list_head *target; page = lru_to_page(src); prefetchw_prev_lru_page(page, src, flags); BUG_ON(!PageLRU(page)); list_del(&page->lru); - if (unlikely(get_page_testone(page))) { + target = src; + if (likely(get_page_unless_zero(page))) { /* - * It is being freed elsewhere + * Be careful not to clear PageLRU until after we're + * sure the page is not being freed elsewhere -- the + * page release code relies on it. */ - __put_page(page); - list_add(&page->lru, src); - continue; - } + ClearPageLRU(page); + target = dst; + nr_taken++; + } /* else it is being freed elsewhere */ - /* - * Be careful not to clear PageLRU until after we're sure - * the page is not being freed elsewhere -- the page release - * code relies on it. - */ - ClearPageLRU(page); - list_add(&page->lru, dst); - nr_taken++; + list_add(&page->lru, target); } *scanned = scan; |