Date:   Mon, 6 Mar 2023 14:31:47 -0500
From:   Mike Snitzer <snitzer@kernel.org>
To:     Hou Tao <houtao@huaweicloud.com>
Cc:     dm-devel@redhat.com, Alasdair Kergon <agk@redhat.com>,
        Ignat Korchagin <ignat@cloudflare.com>,
        linux-kernel@vger.kernel.org, houtao1@huawei.com
Subject: Re: dm crypt: initialize tasklet in crypt_io_init()
Message-ID: <ZAY/o9ew9AtrCLE5@redhat.com>
References: <20230306134930.2878660-1-houtao@huaweicloud.com>
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On Mon, Mar 06 2023 at  8:49P -0500,
Hou Tao <houtao@huaweicloud.com> wrote:

> From: Hou Tao <houtao1@huawei.com>
> 
> When neither no_read_workqueue nor no_write_workqueue are enabled,
> tasklet_trylock() in crypt_dec_pending() may still return false due to
> an uninitialized state, and dm-crypt will do io completion in io_queue
> instead of current context unnecessarily.

Have you actually experienced this?

> Fix it by initializing io->tasklet in crypt_io_init().

Really would rather avoid always calling tasklet_init(). But I can
optimize it away with a later patch.

Mike