From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757868AbYGAI27 (ORCPT ); Tue, 1 Jul 2008 04:28:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757465AbYGAI20 (ORCPT ); Tue, 1 Jul 2008 04:28:26 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:38203 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757428AbYGAI2T (ORCPT ); Tue, 1 Jul 2008 04:28:19 -0400 Date: Tue, 01 Jul 2008 17:26:51 +0900 From: KOSAKI Motohiro To: LKML , linux-mm , Rik van Riel , Lee Schermerhorn , Andrew Morton , "MinChan Kim" Subject: [resend][PATCH -mm] split_lru: fix pagevec_move_tail() doesn't treat unevictable page Cc: kosaki.motohiro@jp.fujitsu.com In-Reply-To: <20080701155749.37F8.KOSAKI.MOTOHIRO@jp.fujitsu.com> References: <20080701155749.37F8.KOSAKI.MOTOHIRO@jp.fujitsu.com> Message-Id: <20080701172223.3801.KOSAKI.MOTOHIRO@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.42 [ja] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Agghh! I am really stupid. I forgot CCed Andrew ;-) So, I resend this. -------------------------------------- even under writebacking, page can move to unevictable list. so shouldn't pagevec_move_tail() check unevictable? if pagevec_move_tail() doesn't PageUnevictable(), below race can occur. CPU1 CPU2 ================================================================== 1. rotate_reclaimable_page() 2. PageUnevictable(page) return 0 3. local_irq_save() 4. pagevec_move_tail() SetPageUnevictable() //mlock? move to unevictable list 5. spin_lock(&zone->lru_lock); 6. list_move_tail(); (move to inactive list) Signed-off-by: KOSAKI Motohiro --- mm/swap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Index: b/mm/swap.c =================================================================== --- a/mm/swap.c +++ b/mm/swap.c @@ -116,7 +116,7 @@ static void pagevec_move_tail(struct pag zone = pagezone; spin_lock(&zone->lru_lock); } - if (PageLRU(page) && !PageActive(page)) { + if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) { int lru = page_is_file_cache(page); list_move_tail(&page->lru, &zone->lru[lru].list); pgmoved++;