From: Suren Baghdasaryan <surenb@google.com>
To: Michal Hocko <mhocko@suse.com>
Cc: linux-api@vger.kernel.org, linux-mm <linux-mm@kvack.org>,
Andrew Morton <akpm@linux-foundation.org>,
David Rientjes <rientjes@google.com>,
Matthew Wilcox <willy@infradead.org>,
Johannes Weiner <hannes@cmpxchg.org>,
Roman Gushchin <guro@fb.com>, Rik van Riel <riel@surriel.com>,
Minchan Kim <minchan@kernel.org>,
Christian Brauner <christian@brauner.io>,
Oleg Nesterov <oleg@redhat.com>,
Tim Murray <timmurray@google.com>,
kernel-team <kernel-team@android.com>,
LKML <linux-kernel@vger.kernel.org>,
Mel Gorman <mgorman@techsingularity.net>
Subject: Re: [RFC]: userspace memory reaping
Date: Tue, 3 Nov 2020 13:28:51 -0800 [thread overview]
Message-ID: <CAJuCfpH4hdyMTdvSyY9uJgMQz-Gfff-ZgWisgx4TVUpq_F_sAw@mail.gmail.com> (raw)
In-Reply-To: <20201103093550.GE21990@dhcp22.suse.cz>
On Tue, Nov 3, 2020 at 1:35 AM Michal Hocko <mhocko@suse.com> wrote:
>
> On Mon 02-11-20 12:29:24, Suren Baghdasaryan wrote:
> [...]
> > To follow up on this. Should I post an RFC implementing SIGKILL_SYNC
> > which in addition to sending a kill signal would also reap the
> > victim's mm in the context of the caller? Maybe having some code will
> > get the discussion moving forward?
>
> Yeah, having a code, even preliminary, might help here. This definitely
> needs a good to go from process management people as that proper is land
> full of surprises...
Hmm. Adding a new SIGKILL_SYNC seems to require quite a surgery...
That will cause a change to SIGRTMIN which is used by glib and also
would affect RTSIG_MAX which I think is also used by the userspace.
I'm not sure such a change would be acceptable...
IIUC, Minchan's alternative suggestion was to do mm reaping from
inside fsync() in cases like these:
pidfd_send_signal(pidfd, SIGKILL); // send SIGKILL as usual
fsync(pidfd); // causes mm reaping in the context of the caller
I can prototype this approach quite easily and quickly and post an RFC
to energize the discussion. Any objections?
> --
> Michal Hocko
> SUSE Labs
next prev parent reply other threads:[~2020-11-03 21:29 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-15 0:43 [RFC]: userspace memory reaping Suren Baghdasaryan
2020-09-15 0:45 ` Suren Baghdasaryan
2020-10-14 12:09 ` Michal Hocko
2020-10-14 16:57 ` Suren Baghdasaryan
2020-10-14 18:39 ` minchan
2020-10-15 9:20 ` Michal Hocko
2020-10-15 18:43 ` Minchan Kim
2020-10-15 19:32 ` Suren Baghdasaryan
2020-10-15 19:25 ` Suren Baghdasaryan
2020-11-02 20:29 ` Suren Baghdasaryan
2020-11-03 9:35 ` Michal Hocko
2020-11-03 21:28 ` Suren Baghdasaryan [this message]
2020-11-03 21:32 ` Minchan Kim
2020-11-03 21:40 ` Suren Baghdasaryan
2020-11-03 21:46 ` Minchan Kim
2020-11-04 6:58 ` Michal Hocko
2020-11-04 20:40 ` Minchan Kim
2020-11-05 12:20 ` Michal Hocko
2020-11-05 16:50 ` Suren Baghdasaryan
2020-11-05 17:07 ` Minchan Kim
2020-11-05 17:16 ` Michal Hocko
2020-11-05 17:21 ` Suren Baghdasaryan
2020-11-05 17:41 ` Minchan Kim
2020-11-05 17:43 ` Michal Hocko
2020-11-05 18:02 ` Suren Baghdasaryan
2020-11-13 17:37 ` Suren Baghdasaryan
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