Subject: Re: [PATCH -next V2] blk-mq: fix tag_get wait task can't be awakened
To:     Laibin Qiu <qiulaibin@huawei.com>, <axboe@kernel.dk>,
        <ming.lei@redhat.com>
CC:     <linux-block@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <20220105035644.3311480-1-qiulaibin@huawei.com>
From:   John Garry <john.garry@huawei.com>
Message-ID: <ddb3c319-65f3-6045-d0ac-764c7dcc84c2@huawei.com>
Date:   Wed, 5 Jan 2022 10:56:25 +0000
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On 05/01/2022 03:56, Laibin Qiu wrote:
> +
>   /*
>    * If a previously inactive queue goes active, bump the active user count.
>    * We need to do this before try to allocate driver tag, then even if fail
> @@ -23,10 +38,16 @@
>    */
>   bool __blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx)
>   {
> +	unsigned int users;
> +
>   	if (!test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state) &&
> -	    !test_and_set_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state))
> +	    !test_and_set_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state)) {
>   		atomic_inc(&hctx->tags->active_queues);
>   
> +		users = atomic_read(&hctx->tags->active_queues);
> +		blk_mq_update_wake_batch(hctx->tags, users);
> +	}
> +
>   	return true;
>   }
>   

This code looks old to me. Which baseline is used here?

Thanks,
John