From: Andrew Morton <akpm@linux-foundation.org>
To: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Vlastimil Babka <vbabka@suse.cz>,
Michal Hocko <mhocko@kernel.org>,
Johannes Weiner <hannes@cmpxchg.org>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] vmpressure: Fix subtree pressure detection
Date: Mon, 1 Feb 2016 22:32:36 -0800 [thread overview]
Message-ID: <20160201223236.d7393b62.akpm@linux-foundation.org> (raw)
In-Reply-To: <20160129083749.GB4952@esperanza>
On Fri, 29 Jan 2016 11:37:49 +0300 Vladimir Davydov <vdavydov@virtuozzo.com> wrote:
> On Thu, Jan 28, 2016 at 08:24:30PM +0100, Vlastimil Babka wrote:
> > On 28.1.2016 16:55, Michal Hocko wrote:
> > > On Wed 27-01-16 19:28:57, Vladimir Davydov wrote:
> > >> When vmpressure is called for the entire subtree under pressure we
> > >> mistakenly use vmpressure->scanned instead of vmpressure->tree_scanned
> > >> when checking if vmpressure work is to be scheduled. This results in
> > >> suppressing all vmpressure events in the legacy cgroup hierarchy. Fix
> > >> it.
> > >>
> > >> Fixes: 8e8ae645249b ("mm: memcontrol: hook up vmpressure to socket pressure")
> > >> Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
> > >
> > > a = b += c made me scratch my head for a second but this looks correct
> >
> > Ugh, it's actually a = b += a
> >
> > While clever and compact, this will make scratch their head anyone looking at
> > the code in the future. Is it worth it?
>
> I'm just trying to be consistend with the !tree case, where we do
> exactly the same.
I stared suspiciously at it for a while, decided to let it go.
Possibly we can remove local `scanned' altogether. No matter, someone
will clean it all up sometime.
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
prev parent reply other threads:[~2016-02-02 6:29 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-27 16:28 [PATCH] vmpressure: Fix subtree pressure detection Vladimir Davydov
2016-01-27 18:47 ` Johannes Weiner
2016-01-28 15:55 ` Michal Hocko
2016-01-28 19:24 ` Vlastimil Babka
2016-01-29 8:37 ` Vladimir Davydov
2016-02-02 6:32 ` Andrew Morton [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=20160201223236.d7393b62.akpm@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=hannes@cmpxchg.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mhocko@kernel.org \
--cc=vbabka@suse.cz \
--cc=vdavydov@virtuozzo.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).