Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759615Ab1FXOqA (ORCPT ); Fri, 24 Jun 2011 10:46:00 -0400 Received: from cantor2.suse.de ([195.135.220.15]:39022 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759403Ab1FXOpD (ORCPT ); Fri, 24 Jun 2011 10:45:03 -0400 From: Mel Gorman To: Andrew Morton Cc: =?UTF-8?q?P=C3=A1draig=20Brady?= , James Bottomley , Colin King , Minchan Kim , Andrew Lutomirski , Rik van Riel , Johannes Weiner , linux-mm , linux-kernel , Mel Gorman Subject: [PATCH 3/4] mm: vmscan: Evaluate the watermarks against the correct classzone Date: Fri, 24 Jun 2011 15:44:56 +0100 Message-Id: <1308926697-22475-4-git-send-email-mgorman@suse.de> X-Mailer: git-send-email 1.7.3.4 In-Reply-To: <1308926697-22475-1-git-send-email-mgorman@suse.de> References: <1308926697-22475-1-git-send-email-mgorman@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1273 Lines: 35 When deciding if kswapd is sleeping prematurely, the classzone is taken into account but this is different to what balance_pgdat() and the allocator are doing. Specifically, the DMA zone will be checked based on the classzone used when waking kswapd which could be for a GFP_KERNEL or GFP_HIGHMEM request. The lowmem reserve limit kicks in, the watermark is not met and kswapd thinks its sleeping prematurely keeping kswapd awake in error. Reported-and-tested-by: Pádraig Brady Signed-off-by: Mel Gorman --- mm/vmscan.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 9cebed1..a76b6cc2 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2341,7 +2341,7 @@ static bool sleeping_prematurely(pg_data_t *pgdat, int order, long remaining, } if (!zone_watermark_ok_safe(zone, order, high_wmark_pages(zone), - classzone_idx, 0)) + i, 0)) all_zones_ok = false; else balanced += zone->present_pages; -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/