linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Michal Hocko <mhocko@suse.com>
To: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>,
	cgroups@vger.kernel.org, linux-mm@kvack.org,
	Andrew Morton <akpm@linux-foundation.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Vladimir Davydov <vdavydov.dev@gmail.com>,
	Waiman Long <longman@redhat.com>
Subject: Re: [PATCH] mm/memcontrol: Disable on PREEMPT_RT
Date: Mon, 13 Dec 2021 11:08:26 +0100	[thread overview]
Message-ID: <YbcbmvQk+Sgdsi9G@dhcp22.suse.cz> (raw)
In-Reply-To: <YbNwmUMPFM/MO0cX@linutronix.de>

On Fri 10-12-21 16:22:01, Sebastian Andrzej Siewior wrote:
[...]
I am sorry but I didn't get to read and digest the rest of the message
yet. Let me just point out this

> The problematic part here is mem_cgroup_tree_per_node::lock which can
> not be acquired with disabled interrupts on PREEMPT_RT.  The "locking
> scope" is not always clear to me.  Also, if it is _just_ the counter,
> then we might solve this differently.

I do not think you should be losing sleep over soft limit reclaim. This
is certainly not something to be used for RT workloads and rather than
touching that code I think it makes some sense to simply disallow soft
limit with RT enabled (i.e. do not allow to set any soft limit).
-- 
Michal Hocko
SUSE Labs


  reply	other threads:[~2021-12-13 10:08 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-12-07 15:52 Sebastian Andrzej Siewior
2021-12-07 16:00 ` Waiman Long
2021-12-07 16:55 ` Johannes Weiner
2021-12-10 15:22   ` Sebastian Andrzej Siewior
2021-12-13 10:08     ` Michal Hocko [this message]
2021-12-15 16:47       ` Sebastian Andrzej Siewior
2021-12-15 16:56         ` Michal Hocko
2021-12-15 17:13           ` Sebastian Andrzej Siewior
2021-12-15 18:44             ` Michal Hocko
2021-12-16  7:51               ` Sebastian Andrzej Siewior

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=YbcbmvQk+Sgdsi9G@dhcp22.suse.cz \
    --to=mhocko@suse.com \
    --cc=akpm@linux-foundation.org \
    --cc=bigeasy@linutronix.de \
    --cc=cgroups@vger.kernel.org \
    --cc=hannes@cmpxchg.org \
    --cc=linux-mm@kvack.org \
    --cc=longman@redhat.com \
    --cc=tglx@linutronix.de \
    --cc=vdavydov.dev@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