From patchwork Fri May 13 14:03:24 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mel Gorman X-Patchwork-Id: 95487 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 920C8B6EEE for ; Sat, 14 May 2011 00:04:07 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759311Ab1EMODg (ORCPT ); Fri, 13 May 2011 10:03:36 -0400 Received: from cantor2.suse.de ([195.135.220.15]:53088 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758985Ab1EMODd (ORCPT ); Fri, 13 May 2011 10:03:33 -0400 Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.221.2]) by mx2.suse.de (Postfix) with ESMTP id 5AE608738D; Fri, 13 May 2011 16:03:32 +0200 (CEST) From: Mel Gorman To: Andrew Morton Cc: James Bottomley , Colin King , Raghavendra D Prabhu , Jan Kara , Chris Mason , Christoph Lameter , Pekka Enberg , Rik van Riel , Johannes Weiner , linux-fsdevel , linux-mm , linux-kernel , linux-ext4 , Mel Gorman Subject: [PATCH 4/4] mm: vmscan: If kswapd has been running too long, allow it to sleep Date: Fri, 13 May 2011 15:03:24 +0100 Message-Id: <1305295404-12129-5-git-send-email-mgorman@suse.de> X-Mailer: git-send-email 1.7.3.4 In-Reply-To: <1305295404-12129-1-git-send-email-mgorman@suse.de> References: <1305295404-12129-1-git-send-email-mgorman@suse.de> Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org Under constant allocation pressure, kswapd can be in the situation where sleeping_prematurely() will always return true even if kswapd has been running a long time. Check if kswapd needs to be scheduled. Signed-off-by: Mel Gorman Acked-by: Rik van Riel --- mm/vmscan.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index af24d1e..4d24828 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2251,6 +2251,10 @@ static bool sleeping_prematurely(pg_data_t *pgdat, int order, long remaining, unsigned long balanced = 0; bool all_zones_ok = true; + /* If kswapd has been running too long, just sleep */ + if (need_resched()) + return false; + /* If a direct reclaimer woke kswapd within HZ/10, it's premature */ if (remaining) return true;