linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Baoquan He <bhe@redhat.com>
To: Michal Hocko <mhocko@kernel.org>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	akpm@linux-foundation.org, x86@kernel.org
Subject: Re: [PATCH] x86/mm: Remove the redundant conditional check
Date: Wed, 11 Mar 2020 09:15:10 +0800	[thread overview]
Message-ID: <20200311011510.GH27711@MiWiFi-R3L-srv> (raw)
In-Reply-To: <20200310143240.GL8447@dhcp22.suse.cz>

On 03/10/20 at 03:32pm, Michal Hocko wrote:
> On Tue 10-03-20 22:23:41, Baoquan He wrote:
> > On 03/10/20 at 11:10am, Michal Hocko wrote:
> > > On Sun 08-03-20 09:35:11, Baoquan He wrote:
> > > > In commit f70029bbaacbfa8f0 ("mm, memory_hotplug: drop CONFIG_MOVABLE_NODE"),
> > > > the dependency on CONFIG_MOVABLE_NODE was removed for N_MEMORY, so the
> > > > conditional check in paging_init() doesn't make any sense any more.
> > > > Remove it.
> > > 
> > > Please expand more. I would really have to refresh the intention of the
> > > code but from a quick look at the code CONFIG_HIGHMEM still makes
> > > N_MEMORY != N_NORMAL_MEMORY. So what what does this change mean for that
> > > config?
> > 
> > Thanks for looking into this. I was trying to explain that
> > CONFIG_MOVABLE_NODE made N_MEMORY have chance to take different enum
> > value.
> >  
> > Do you think the below saying is OK to you?
> >  
> > ~~~
> > In commit f70029bbaacb ("mm, memory_hotplug: drop CONFIG_MOVABLE_NODE"),
> > the dependency on CONFIG_MOVABLE_NODE was removed for N_MEMORY.  Before
> > commit f70029bbaacb, CONFIG_HIGHMEM && !CONFIG_MOVABLE_NODE could make
> > (N_MEMORY == N_NORMAL_MEMORY) be true. After commit f70029bbaacb, N_MEMORY
> > doesn't have any chance to be equal to N_NORMAL_MEMORY. So the  conditional
> > check in paging_init() doesn't make any sense any more. Let's remove it.
> 
> Yes this describes the matter much better. I have obviously misread the
> code when looking at it this morning. Being explicit in the changelog
> would have helped at least me. Thanks!

Will update log and repost, thanks.



      reply	other threads:[~2020-03-11  1:15 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-08  1:35 [PATCH] x86/mm: Remove the redundant conditional check Baoquan He
2020-03-10 10:10 ` Michal Hocko
2020-03-10 14:23   ` Baoquan He
2020-03-10 14:32     ` Michal Hocko
2020-03-11  1:15       ` Baoquan He [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200311011510.GH27711@MiWiFi-R3L-srv \
    --to=bhe@redhat.com \
    --cc=akpm@linux-foundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mhocko@kernel.org \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).