From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with SMTP id 486EC6B01DA for ; Wed, 24 Mar 2010 08:11:49 -0400 (EDT) Received: by pxi32 with SMTP id 32so2288481pxi.1 for ; Wed, 24 Mar 2010 05:11:45 -0700 (PDT) From: Bob Liu Subject: [RFC][PATCH] shrink_page_list: save page_mapped() to local val Date: Wed, 24 Mar 2010 20:11:27 +0800 Message-Id: <1269432687-1580-1-git-send-email-lliubbo@gmail.com> Sender: owner-linux-mm@kvack.org To: akpm@linux-foundation.org Cc: linux-mm@kvack.org, kosaki.motohiro@jp.fujitsu.com, riel@redhat.com, Bob Liu List-ID: In funtion shrink_page_list(), page_mapped() is called several times,save it to local val to reduce atomic_read. Signed-off-by: Bob Liu --- mm/vmscan.c | 8 +++++--- 1 files changed, 5 insertions(+), 3 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 79c8098..08cc3ac 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -637,6 +637,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, struct address_space *mapping; struct page *page; int may_enter_fs; + int page_mapcount; cond_resched(); @@ -653,11 +654,12 @@ static unsigned long shrink_page_list(struct list_head *page_list, if (unlikely(!page_evictable(page, NULL))) goto cull_mlocked; - if (!sc->may_unmap && page_mapped(page)) + page_mapcount = page_mapped(page); + if (!sc->may_unmap && page_mapcount) goto keep_locked; /* Double the slab pressure for mapped and swapcache pages */ - if (page_mapped(page) || PageSwapCache(page)) + if (page_mapcount || PageSwapCache(page)) sc->nr_scanned++; may_enter_fs = (sc->gfp_mask & __GFP_FS) || @@ -707,7 +709,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, * The page is mapped into the page tables of one or more * processes. Try to unmap it here. */ - if (page_mapped(page) && mapping) { + if (page_mapcount && mapping) { switch (try_to_unmap(page, TTU_UNMAP)) { case SWAP_FAIL: goto activate_locked; -- 1.5.6.3 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org