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Message-ID: <a4ba2441-83eb-dde2-09ae-7c5f42ff6ad3@acm.org>
Date:   Mon, 20 Dec 2021 09:10:14 -0800
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Subject: Re: [PATCH] nbd: Don't use workqueue to handle recv work
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To:     Xie Yongji <xieyongji@bytedance.com>, josef@toxicpanda.com,
        axboe@kernel.dk
Cc:     linux-block@vger.kernel.org, nbd@other.debian.org,
        linux-kernel@vger.kernel.org
References: <20211220122241.150-1-xieyongji@bytedance.com>
From:   Bart Van Assche <bvanassche@acm.org>
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On 12/20/21 04:22, Xie Yongji wrote:
> The rescuer thread might take over the works queued on
> the workqueue when the worker thread creation timed out.
> If this happens, we have no chance to create multiple
> recv threads which causes I/O hung on this nbd device.
> 
> To fix it, this tries to create kthreads directly to
> handle the recv work instead of using workqueue.

Why a kthread instead of only removing the WQ_MEM_RECLAIM flag from the 
alloc_workqueue() call? This should have been explained in the patch 
description. Additionally, a Fixes: tag is missing.

Thanks,

Bart.