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Date:   Tue, 9 Mar 2021 17:19:31 +0000
From:   Christoph Hellwig <hch@infradead.org>
To:     Sergei Shtepa <sergei.shtepa@veeam.com>
Cc:     snitzer@redhat.com, agk@redhat.com, hare@suse.de, song@kernel.org,
        axboe@kernel.dk, dm-devel@redhat.com, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org,
        linux-api@vger.kernel.org, pavel.tide@veeam.com
Subject: Re: [PATCH v6 1/4] block: add blk_mq_is_queue_frozen()
Message-ID: <20210309171931.GA201344@infradead.org>
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On Wed, Mar 03, 2021 at 03:30:15PM +0300, Sergei Shtepa wrote:
> +bool blk_mq_is_queue_frozen(struct request_queue *q)
> +{
> +	bool ret;
> +
> +	mutex_lock(&q->mq_freeze_lock);
> +	ret = percpu_ref_is_dying(&q->q_usage_counter) && percpu_ref_is_zero(&q->q_usage_counter);

Please avoid the overly long line.

Also maybe frozen is a better name for the variable currently called
ret?