From: "Michal Koutný" <mkoutny@suse.com>
To: Quanyang Wang <quanyang.wang@windriver.com>
Cc: Ming Lei <ming.lei@redhat.com>, Tejun Heo <tj@kernel.org>,
Zefan Li <lizefan.x@bytedance.com>,
Johannes Weiner <hannes@cmpxchg.org>,
Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
Andrii Nakryiko <andrii@kernel.org>, Jens Axboe <axboe@kernel.dk>,
Roman Gushchin <guro@fb.com>,
cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
netdev@vger.kernel.org, bpf@vger.kernel.org
Subject: Re: [V2][PATCH] cgroup: fix memory leak caused by missing cgroup_bpf_offline
Date: Tue, 19 Oct 2021 19:10:26 +0200 [thread overview]
Message-ID: <YW78AohHqgqM9Cuw@blackbook> (raw)
In-Reply-To: <a84aedfe-6ecf-7f48-505e-a11acfd6204c@windriver.com>
Hi.
On Tue, Oct 19, 2021 at 06:41:14PM +0800, Quanyang Wang <quanyang.wang@windriver.com> wrote:
> So I add 2 "Fixes tags" here to indicate that 2 commits introduce two
> different issues.
AFAIU, both the changes are needed to cause the leak, a single patch
alone won't cause the issue. Is that correct? (Perhaps not as I realize,
see below.)
But on second thought, the problem is the missing percpu_ref_exit() in
the (root) cgroup release path and percpu counter would allocate the
percpu_count_ptr anyway, so 4bfc0bb2c60e is only making the leak more
visible. Is this correct?
I agree the commit 2b0d3d3e4fcf ("percpu_ref: reduce memory footprint of
percpu_ref in fast path") alone did nothing wrong.
[On a related (but independent) note, there seems to be an optimization
opportunity in not dealing with cgroup_bpf at all on the non-default
hierarchies.]
Regards,
Michal
next prev parent reply other threads:[~2021-10-19 17:10 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-18 7:56 [V2][PATCH] cgroup: fix memory leak caused by missing cgroup_bpf_offline quanyang.wang
2021-10-18 9:02 ` Ming Lei
2021-10-18 10:06 ` Quanyang Wang
2021-10-18 12:59 ` Ming Lei
2021-10-18 12:59 ` Ming Lei
2021-10-19 10:41 ` Quanyang Wang
2021-10-19 10:41 ` Quanyang Wang
2021-10-19 17:10 ` Michal Koutný [this message]
2021-10-20 2:17 ` Ming Lei
2021-10-20 5:22 ` Quanyang Wang
2021-10-20 5:22 ` Quanyang Wang
2021-10-20 17:28 ` Michal Koutný
2021-10-22 11:03 ` Quanyang Wang
2021-10-22 11:03 ` Quanyang Wang
2021-10-20 5:16 ` Quanyang Wang
2021-10-20 5:16 ` Quanyang Wang
2021-10-19 10:41 ` Quanyang Wang
2021-10-22 1:30 ` Roman Gushchin
2021-10-22 1:30 ` Roman Gushchin
2021-10-22 11:55 ` Quanyang Wang
2021-10-22 21:29 ` Alexei Starovoitov
2021-10-22 21:29 ` Alexei Starovoitov
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=YW78AohHqgqM9Cuw@blackbook \
--to=mkoutny@suse.com \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=axboe@kernel.dk \
--cc=bpf@vger.kernel.org \
--cc=cgroups@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=guro@fb.com \
--cc=hannes@cmpxchg.org \
--cc=linux-kernel@vger.kernel.org \
--cc=lizefan.x@bytedance.com \
--cc=ming.lei@redhat.com \
--cc=netdev@vger.kernel.org \
--cc=quanyang.wang@windriver.com \
--cc=tj@kernel.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.