linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: osalvador <osalvador@suse.de>
To: Michal Hocko <mhocko@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>
Cc: Wei Yang <richard.weiyang@gmail.com>,
	linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm: use managed_zone() for more exact check in zone iteration
Date: Fri, 16 Nov 2018 12:05:04 +0100	[thread overview]
Message-ID: <1542366304.3020.15.camel@suse.de> (raw)
In-Reply-To: <20181116095720.GE14706@dhcp22.suse.cz>

On Fri, 2018-11-16 at 10:57 +0100, Michal Hocko wrote:
> On Thu 15-11-18 13:37:35, Andrew Morton wrote:
> [...]
> > Worse, the situations in which managed_zone() != populated_zone()
> > are
> > rare(?), so it will take a long time for problems to be discovered,
> > I
> > expect.
> 
> We would basically have to deplete the whole zone by the bootmem
> allocator or pull out all pages from the page allocator. E.g. memory
> hotplug decreases both managed and present counters. I am actually
> not
> sure that is 100% correct (put on my TODO list to check). There is no
> consistency in that regards.

We can only offline non-reserved pages (so, managed pages).
Since present pages holds reserved_pages + managed_pages, decreasing
both should be fine unless I am mistaken.

Oscar Salvador




  reply	other threads:[~2018-11-16 11:05 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-11-14 23:50 [PATCH] mm: use managed_zone() for more exact check in zone iteration Wei Yang
2018-11-15 21:37 ` Andrew Morton
2018-11-16  4:41   ` Wei Yang
2018-11-16  9:57   ` Michal Hocko
2018-11-16 11:05     ` osalvador [this message]
2018-11-16 11:26       ` Michal Hocko
2018-11-16 15:58         ` Wei Yang
2018-11-16 17:07           ` Michal Hocko
2018-11-16 10:24 ` Michal Hocko
2018-11-21  3:05   ` Wei Yang

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=1542366304.3020.15.camel@suse.de \
    --to=osalvador@suse.de \
    --cc=akpm@linux-foundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mhocko@kernel.org \
    --cc=richard.weiyang@gmail.com \
    /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).