From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754422AbdGNM40 (ORCPT ); Fri, 14 Jul 2017 08:56:26 -0400 Received: from mx2.suse.de ([195.135.220.15]:52765 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754363AbdGNM4Y (ORCPT ); Fri, 14 Jul 2017 08:56:24 -0400 Date: Fri, 14 Jul 2017 13:56:16 +0100 From: Mel Gorman To: Michal Hocko Cc: linux-mm@kvack.org, Andrew Morton , Johannes Weiner , Vlastimil Babka , LKML , linux-api@vger.kernel.org Subject: Re: [PATCH 1/9] mm, page_alloc: rip out ZONELIST_ORDER_ZONE Message-ID: <20170714125616.clbp4ezgtoon6cmk@suse.de> References: <20170714080006.7250-1-mhocko@kernel.org> <20170714080006.7250-2-mhocko@kernel.org> <20170714093650.l67vbem2g4typkta@suse.de> <20170714104756.GD2618@dhcp22.suse.cz> <20170714111633.gk5rpu2d5ghkbrrd@suse.de> <20170714113840.GI2618@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20170714113840.GI2618@dhcp22.suse.cz> User-Agent: NeoMutt/20170421 (1.8.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 14, 2017 at 01:38:40PM +0200, Michal Hocko wrote: > On Fri 14-07-17 12:16:33, Mel Gorman wrote: > > On Fri, Jul 14, 2017 at 12:47:57PM +0200, Michal Hocko wrote: > > > > That should to be "default" because the original code would have the proc > > > > entry display "default" unless it was set at runtime. Pretty weird I > > > > know but it's always possible someone is parsing the original default > > > > and not handling it properly. > > > > > > Ohh, right! That is indeed strange. Then I guess it would be probably > > > better to simply return Node to make it clear what the default is. What > > > do you think? > > > > > > > That would work too. The casing still matches. > > This folded in? > --- > From c7c36f011590680b254813be00ed791ddbc1bf1c Mon Sep 17 00:00:00 2001 > From: Michal Hocko > Date: Fri, 14 Jul 2017 13:36:05 +0200 > Subject: [PATCH] fold me "mm, page_alloc: rip out ZONELIST_ORDER_ZONE" > > - do not print Default in sysctl handler because our behavior was rather > inconsistent in the past numa_zonelist_order was lowecase while > zonelist_order_name was uppercase so boot time unchanged value woul > print lowercase while updated value could be uppercase. Print "Node" > which is the default instead - Mel > > Signed-off-by: Michal Hocko > --- > mm/page_alloc.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index dd4c96edcec3..49bade7ff049 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -4828,8 +4828,8 @@ int numa_zonelist_order_handler(struct ctl_table *table, int write, > int ret; > > if (!write) { > - int len = sizeof("Default"); > - if (copy_to_user(buffer, "Default", len)) > + int len = sizeof("Node"); > + if (copy_to_user(buffer, "Node", len)) > return -EFAULT; Ok for the name. But what's with using sizeof? The type is char * so it just happens to work for Default, but not for Node. Also strongly suggest you continue using proc_dostring because it catches all the corner-cases that can occur. -- Mel Gorman SUSE Labs