From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1752078AbcFUWlK (ORCPT <rfc822;w@1wt.eu>);
	Tue, 21 Jun 2016 18:41:10 -0400
Received: from mail.linuxfoundation.org ([140.211.169.12]:44513 "EHLO
	mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1751547AbcFUWlI (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Tue, 21 Jun 2016 18:41:08 -0400
Date: Tue, 21 Jun 2016 15:32:06 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Mel Gorman <mgorman@techsingularity.net>
Cc: Linux-MM <linux-mm@kvack.org>, Rik van Riel <riel@surriel.com>,
        Vlastimil Babka <vbabka@suse.cz>, Johannes Weiner <hannes@cmpxchg.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 16/27] mm: Move page mapped accounting to the node
Message-Id: <20160621153206.2d72954b22dddee7f1d8b9a5@linux-foundation.org>
In-Reply-To: <1466518566-30034-17-git-send-email-mgorman@techsingularity.net>
References: <1466518566-30034-1-git-send-email-mgorman@techsingularity.net>
	<1466518566-30034-17-git-send-email-mgorman@techsingularity.net>
X-Mailer: Sylpheed 3.4.1 (GTK+ 2.24.23; x86_64-pc-linux-gnu)
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Tue, 21 Jun 2016 15:15:55 +0100 Mel Gorman <mgorman@techsingularity.net> wrote:

> Reclaim makes decisions based on the number of pages that are mapped
> but it's mixing node and zone information. Account NR_FILE_MAPPED and
> NR_ANON_PAGES pages on the node.

<wading through rejects>

Boy, the difference between

	__mod_zone_page_state(page_zone(page), ...

and

	__mod_node_page_state(page_pgdat(page), ...

is looking subtle.  When and why to use one versus the other.  I'm not
seeing any explanation of this in there but haven't yet looked hard.