From: Bart Van Assche <bvanassche@acm.org>
To: Yu Kuai <yukuai1@huaweicloud.com>,
tj@kernel.org, josef@toxicpanda.com, jack@suse.cz,
axboe@kernel.dk
Cc: cgroups@vger.kernel.org, linux-block@vger.kernel.org,
linux-kernel@vger.kernel.org, yukuai3@huawei.com,
yi.zhang@huawei.com, yangerkun@huawei.com
Subject: Re: [PATCH 2/2] blk-ioprio: remove per-disk structure
Date: Thu, 11 Jul 2024 11:03:52 -0700 [thread overview]
Message-ID: <4c8f1e4e-1b15-4afa-b1e2-084e0c4caeec@acm.org> (raw)
In-Reply-To: <20240711090059.3998565-3-yukuai1@huaweicloud.com>
On 7/11/24 2:00 AM, Yu Kuai wrote:
> ioprio works on the blk-cgroup level, all disks in the same cgroup
> are the same, and the struct ioprio_blkg doesn't have anything in it.
> Hence register the policy is enough, because cpd_alloc/free_fn will
> be handled for each blk-cgroup, and there is no need to activate the
> policy for disk.
As one can see in the output of git grep -nHEB1 '>pd_(alloc|free)_fn\(',
none of the pd_alloc_fn / pd_free_fn callers checks whether or not these
pointers are NULL. Hence my question why this patch does not trigger any
NULL pointer dereferences?
Thanks,
Bart.
next prev parent reply other threads:[~2024-07-11 18:03 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-07-11 9:00 [PATCH 0/2] blk-ioprio: remove per-disk structure Yu Kuai
2024-07-11 9:00 ` [PATCH 1/2] blk-ioprio: remove ioprio_blkcg_from_bio() Yu Kuai
2024-07-11 18:00 ` Bart Van Assche
2024-07-11 9:00 ` [PATCH 2/2] blk-ioprio: remove per-disk structure Yu Kuai
2024-07-11 18:03 ` Bart Van Assche [this message]
2024-07-12 1:10 ` Yu Kuai
2024-07-12 1:25 ` Yu Kuai
2024-07-12 5:22 ` Christoph Hellwig
2024-07-12 6:51 ` Yu Kuai
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=4c8f1e4e-1b15-4afa-b1e2-084e0c4caeec@acm.org \
--to=bvanassche@acm.org \
--cc=axboe@kernel.dk \
--cc=cgroups@vger.kernel.org \
--cc=jack@suse.cz \
--cc=josef@toxicpanda.com \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=tj@kernel.org \
--cc=yangerkun@huawei.com \
--cc=yi.zhang@huawei.com \
--cc=yukuai1@huaweicloud.com \
--cc=yukuai3@huawei.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