From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755455Ab2GaEuS (ORCPT ); Tue, 31 Jul 2012 00:50:18 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:48548 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755367Ab2GaEuJ (ORCPT ); Tue, 31 Jul 2012 00:50:09 -0400 Message-Id: <20120731044313.021299907@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Tue, 31 Jul 2012 05:43:21 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Konstantin Khlebnikov , Pekka Enberg , Minchan Kim , KAMEZAWA Hiroyuki , Wu Fengguang , Johannes Weiner , Nick Piggin , Mel Gorman , Shaohua Li , Rik van Riel Subject: [ 11/73] vmscan: activate executable pages after first usage In-Reply-To: <20120731044310.013763753@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:21c:bfff:fe03:f805 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Konstantin Khlebnikov commit c909e99364c8b6ca07864d752950b6b4ecf6bef4 upstream. Stable note: Not tracked in Bugzilla. There were reports of shared mapped pages being unfairly reclaimed in comparison to older kernels. This is being addressed over time. Logic added in commit 8cab4754d24a0 ("vmscan: make mapped executable pages the first class citizen") was noticeably weakened in commit 645747462435d84 ("vmscan: detect mapped file pages used only once"). Currently these pages can become "first class citizens" only after second usage. After this patch page_check_references() will activate they after first usage, and executable code gets yet better chance to stay in memory. Signed-off-by: Konstantin Khlebnikov Cc: Pekka Enberg Cc: Minchan Kim Cc: KAMEZAWA Hiroyuki Cc: Wu Fengguang Cc: Johannes Weiner Cc: Nick Piggin Cc: Mel Gorman Cc: Shaohua Li Cc: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings --- mm/vmscan.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/mm/vmscan.c b/mm/vmscan.c index 753c1e6..753a2dc 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -718,6 +718,12 @@ static enum page_references page_check_references(struct page *page, if (referenced_page || referenced_ptes > 1) return PAGEREF_ACTIVATE; + /* + * Activate file-backed executable pages after first usage. + */ + if (vm_flags & VM_EXEC) + return PAGEREF_ACTIVATE; + return PAGEREF_KEEP; }