From: Michal Hocko <mhocko@suse.com>
To: osalvador@suse.de
Cc: Wei Yang <richard.weiyang@gmail.com>,
akpm@linux-foundation.org, linux-mm@kvack.org
Subject: Re: [PATCH] mm, hotplug: protect nr_zones with pgdat_resize_lock()
Date: Tue, 20 Nov 2018 09:48:08 +0100 [thread overview]
Message-ID: <20181120084808.GC22247@dhcp22.suse.cz> (raw)
In-Reply-To: <3ba8d8c524d86af52e4c1fddc2d45734@suse.de>
On Tue 20-11-18 08:58:11, osalvador@suse.de wrote:
> > On the other hand I would like to see the global lock to go away because
> > it causes scalability issues and I would like to change it to a range
> > lock. This would make this race possible.
> >
> > That being said this is more of a preparatory work than a fix. One could
> > argue that pgdat resize lock is abused here but I am not convinced a
> > dedicated lock is much better. We do take this lock already and spanning
> > its scope seems reasonable. An update to the documentation is due.
>
> Would not make more sense to move it within the pgdat lock
> in move_pfn_range_to_zone?
yes, that was what I meant originally and I haven't really looked closer
to the diff itself because I've stopped right at the description.
> The call from free_area_init_core is safe as we are single-thread there.
>
> And if we want to move towards a range locking, I even think it would be
> more
> consistent if we move it within the zone's span lock (which is already
> wrapped with a pgdat lock).
Agreed!
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2018-11-20 8:48 UTC|newest]
Thread overview: 40+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-20 1:48 [PATCH] mm, hotplug: protect nr_zones with pgdat_resize_lock() Wei Yang
2018-11-20 7:31 ` Michal Hocko
2018-11-20 7:58 ` osalvador
2018-11-20 8:48 ` Michal Hocko [this message]
2018-11-21 2:52 ` Wei Yang
2018-11-21 7:15 ` Michal Hocko
2018-11-22 1:52 ` Wei Yang
2018-11-22 8:39 ` Michal Hocko
2018-11-26 2:28 ` Wei Yang
2018-11-26 8:16 ` Michal Hocko
2018-11-26 9:06 ` Wei Yang
2018-11-26 10:03 ` Michal Hocko
2018-11-27 0:18 ` Wei Yang
2018-11-27 3:12 ` Wei Yang
2018-11-27 13:16 ` Michal Hocko
2018-11-27 23:56 ` Wei Yang
2018-11-21 8:24 ` osalvador
2018-11-21 2:44 ` Wei Yang
2018-11-21 7:14 ` Michal Hocko
2018-11-22 10:12 ` [PATCH v2] mm, hotplug: move init_currently_empty_zone() under zone_span_lock protection Wei Yang
2018-11-22 10:15 ` Wei Yang
2018-11-22 10:29 ` Michal Hocko
2018-11-22 14:27 ` Wei Yang
2018-11-22 10:37 ` osalvador
2018-11-22 14:28 ` Wei Yang
2018-11-22 15:26 ` David Hildenbrand
2018-11-22 21:28 ` Wei Yang
2018-11-22 21:53 ` David Hildenbrand
2018-11-22 23:53 ` Wei Yang
2018-11-23 8:42 ` Michal Hocko
2018-11-23 8:46 ` David Hildenbrand
2018-11-26 1:44 ` Wei Yang
2018-11-26 9:24 ` David Hildenbrand
2018-11-27 0:23 ` Wei Yang
2018-11-30 6:58 ` [PATCH v3] " Wei Yang
2018-11-30 9:30 ` David Hildenbrand
2018-12-01 0:27 ` Wei Yang
2018-12-03 10:09 ` David Hildenbrand
2018-12-03 20:37 ` Wei Yang
2018-12-03 20:50 ` [PATCH v4] " 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=20181120084808.GC22247@dhcp22.suse.cz \
--to=mhocko@suse.com \
--cc=akpm@linux-foundation.org \
--cc=linux-mm@kvack.org \
--cc=osalvador@suse.de \
--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).