From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752141AbaJOUGo (ORCPT ); Wed, 15 Oct 2014 16:06:44 -0400 Received: from mail-qg0-f73.google.com ([209.85.192.73]:35759 "EHLO mail-qg0-f73.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751392AbaJOUGl (ORCPT ); Wed, 15 Oct 2014 16:06:41 -0400 X-Greylist: delayed 440 seconds by postgrey-1.27 at vger.kernel.org; Wed, 15 Oct 2014 16:06:41 EDT From: Jamie Liu To: Andrew Morton , Johannes Weiner , Mel Gorman Cc: Greg Thelen , Hugh Dickins , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Jamie Liu Subject: [PATCH] mm: vmscan: count only dirty pages as congested Date: Wed, 15 Oct 2014 12:58:35 -0700 Message-Id: <1413403115-1551-1-git-send-email-jamieliu@google.com> X-Mailer: git-send-email 2.1.0.rc2.206.gedb03e5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org shrink_page_list() counts all pages with a mapping, including clean pages, toward nr_congested if they're on a write-congested BDI. shrink_inactive_list() then sets ZONE_CONGESTED if nr_dirty == nr_congested. Fix this apples-to-oranges comparison by only counting pages for nr_congested if they count for nr_dirty. Signed-off-by: Jamie Liu --- mm/vmscan.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index dcb4707..ad9cd9f 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -875,7 +875,8 @@ static unsigned long shrink_page_list(struct list_head *page_list, * end of the LRU a second time. */ mapping = page_mapping(page); - if ((mapping && bdi_write_congested(mapping->backing_dev_info)) || + if (((dirty || writeback) && mapping && + bdi_write_congested(mapping->backing_dev_info)) || (writeback && PageReclaim(page))) nr_congested++; -- 2.1.0.rc2.206.gedb03e5