public inbox for linux-block@vger.kernel.org
 help / color / mirror / Atom feed
From: Tejun Heo <tj@kernel.org>
To: Yu Kuai <yukuai3@huawei.com>
Cc: axboe@kernel.dk, paolo.valente@linaro.org, fchecconi@gmail.com,
	avanzini.arianna@gmail.com, mkoutny@suse.com,
	cgroups@vger.kernel.org, linux-block@vger.kernel.org,
	linux-kernel@vger.kernel.org, yi.zhang@huawei.com
Subject: Re: [PATCH v2 -next] blk-cgroup: synchoronize blkg creation against policy deactivation
Date: Thu, 14 Oct 2021 13:02:06 -1000	[thread overview]
Message-ID: <YWi27oAU0v5v86eN@slm.duckdns.org> (raw)
In-Reply-To: <20211013124456.3186005-1-yukuai3@huawei.com>

On Wed, Oct 13, 2021 at 08:44:56PM +0800, Yu Kuai wrote:
> @@ -1401,6 +1406,7 @@ void blkcg_deactivate_policy(struct request_queue *q,
>  	if (queue_is_mq(q))
>  		blk_mq_freeze_queue(q);
>  
> +	mutex_lock(&q->blkg_lock);
>  	spin_lock_irq(&q->queue_lock);

Given that deactivation drains q_usage_counter through
blk_mq_freeze_queue(), can't the blkg_conf_prep() just pin the usage count?

Thanks.

-- 
tejun

  reply	other threads:[~2021-10-14 23:02 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-13 12:44 [PATCH v2 -next] blk-cgroup: synchoronize blkg creation against policy deactivation Yu Kuai
2021-10-14 23:02 ` Tejun Heo [this message]
2021-10-15  1:48   ` yukuai (C)

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=YWi27oAU0v5v86eN@slm.duckdns.org \
    --to=tj@kernel.org \
    --cc=avanzini.arianna@gmail.com \
    --cc=axboe@kernel.dk \
    --cc=cgroups@vger.kernel.org \
    --cc=fchecconi@gmail.com \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mkoutny@suse.com \
    --cc=paolo.valente@linaro.org \
    --cc=yi.zhang@huawei.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