From: David Hildenbrand <david@redhat.com>
To: Suren Baghdasaryan <surenb@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Michal Hocko <mhocko@kernel.org>, Michal Hocko <mhocko@suse.com>,
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>,
Christoph Hellwig <hch@infradead.org>,
Oleg Nesterov <oleg@redhat.com>, Jann Horn <jannh@google.com>,
Shakeel Butt <shakeelb@google.com>,
Andy Lutomirski <luto@kernel.org>,
Christian Brauner <christian.brauner@ubuntu.com>,
Florian Weimer <fweimer@redhat.com>,
Jan Engelhardt <jengelh@inai.de>,
Tim Murray <timmurray@google.com>,
Linux API <linux-api@vger.kernel.org>,
linux-mm <linux-mm@kvack.org>,
LKML <linux-kernel@vger.kernel.org>,
kernel-team <kernel-team@android.com>
Subject: Re: [PATCH v2 2/3] mm: introduce process_mrelease system call
Date: Thu, 22 Jul 2021 09:45:42 +0200 [thread overview]
Message-ID: <472b91d2-d678-2d54-b2d0-8618f32e6e69@redhat.com> (raw)
In-Reply-To: <CAJuCfpHWTA+bGfg=aaRzmiszpo1pphJDL2T7=XSzzjfekSgW8w@mail.gmail.com>
>>> Getting a hold of the mm and locking the mmap_lock would be sufficient I guess.
>
> That's exactly what I do here. The simplified sequence is:
>
> task_lock
> if (task_will_free_mem())
> mm=mmget()
> task_unlock
> if (!mm) return;
>
> mmap_read_lock(mm)
> __oom_reap_task_mm(mm)
> mmap_read_unlock(mm)
> mmput(mm)
>
> Or did I misunderstand your comments?
Oh, sorry, my tired eyes confused "put_task_struct()" with
"task_unlock()" and even "mmget()" with "mmgrab()" ...
So this is essentially get_task_mm() with an additional
task_will_free_mem() check.
LGHTM!
:)
--
Thanks,
David / dhildenb
next prev parent reply other threads:[~2021-07-22 7:45 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-18 21:41 [PATCH v2 1/3] mm, oom: move task_will_free_mem up in the file to be used in process_mrelease Suren Baghdasaryan
2021-07-18 21:41 ` [PATCH v2 2/3] mm: introduce process_mrelease system call Suren Baghdasaryan
2021-07-21 8:02 ` David Hildenbrand
2021-07-21 15:43 ` Suren Baghdasaryan
2021-07-21 22:59 ` Suren Baghdasaryan
2021-07-22 7:45 ` David Hildenbrand [this message]
2021-07-18 21:41 ` [PATCH v2 3/3] mm: wire up syscall process_mrelease Suren Baghdasaryan
2021-07-20 12:43 ` [PATCH v2 1/3] mm, oom: move task_will_free_mem up in the file to be used in process_mrelease David Hildenbrand
2021-07-20 16:18 ` Suren Baghdasaryan
2021-07-20 23:07 ` Andrew Morton
2021-07-21 7:30 ` David Hildenbrand
2021-07-21 15:33 ` Suren Baghdasaryan
2021-07-21 16:12 ` David Hildenbrand
2021-07-21 20:19 ` Suren Baghdasaryan
2021-07-21 20:50 ` Andrew Morton
2021-07-21 20:59 ` Suren Baghdasaryan
2021-07-23 1:15 ` Suren Baghdasaryan
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=472b91d2-d678-2d54-b2d0-8618f32e6e69@redhat.com \
--to=david@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=christian.brauner@ubuntu.com \
--cc=christian@brauner.io \
--cc=fweimer@redhat.com \
--cc=guro@fb.com \
--cc=hannes@cmpxchg.org \
--cc=hch@infradead.org \
--cc=jannh@google.com \
--cc=jengelh@inai.de \
--cc=kernel-team@android.com \
--cc=linux-api@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=luto@kernel.org \
--cc=mhocko@kernel.org \
--cc=mhocko@suse.com \
--cc=minchan@kernel.org \
--cc=oleg@redhat.com \
--cc=riel@surriel.com \
--cc=rientjes@google.com \
--cc=shakeelb@google.com \
--cc=surenb@google.com \
--cc=timmurray@google.com \
--cc=willy@infradead.org \
/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).