From: "Michal Koutný" <mkoutny@suse.com>
To: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Cc: Tejun Heo <tj@kernel.org>, Johannes Weiner <hannes@cmpxchg.org>,
cgroups@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>,
linux-hardening@vger.kernel.org,
"Gustavo A. R. Silva" <gustavoars@kernel.org>,
Chen Ridong <chenridong@huaweicloud.com>
Subject: Re: [RFC] cgroup: Avoid thousands of -Wflex-array-member-not-at-end warnings
Date: Tue, 2 Sep 2025 13:17:11 +0200 [thread overview]
Message-ID: <tl6b6chfawtykzrxlmysn6ev7mq7gm764rnlsag7pfme7vhpof@lbwqooaybqmr> (raw)
In-Reply-To: <92912540-23d2-4b18-9002-bac962682caf@embeddedor.com>
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On Tue, Sep 02, 2025 at 09:56:34AM +0200, "Gustavo A. R. Silva" <gustavo@embeddedor.com> wrote:
> If the increase in size is not a problem, then something like this
> works fine (unless there is a problem with moving those two members
> at the end of cgroup_root?):
Please don't forget to tackle cgroup_root allocators. IIUC, this move
towards the end shifts the burden to them.
There's only the rcu_head we care about.
(You seem to be well versed with flex arrays, I was wondering if
something like this could be rearranged to make it work (assuming the
union is at the end of its containers):
union {
struct cgroup *ancestors[];
struct {
struct cgroup *_root_ancestor;
struct cgroup *_low_ancestors[];
};
};
)
Thanks,
Michal
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next prev parent reply other threads:[~2025-09-02 11:17 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-08-30 13:30 [RFC] cgroup: Avoid thousands of -Wflex-array-member-not-at-end warnings Gustavo A. R. Silva
2025-09-01 1:29 ` Chen Ridong
2025-09-01 7:44 ` Gustavo A. R. Silva
2025-09-01 13:37 ` Michal Koutný
2025-09-01 15:21 ` Gustavo A. R. Silva
2025-09-01 15:44 ` Gustavo A. R. Silva
2025-09-01 18:04 ` Michal Koutný
2025-09-01 17:58 ` Michal Koutný
2025-09-02 7:56 ` Gustavo A. R. Silva
2025-09-02 11:17 ` Michal Koutný [this message]
2025-09-02 12:37 ` Gustavo A. R. Silva
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