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Sender: Tejun Heo <htejun@gmail.com>
Date:   Thu, 15 Dec 2022 06:54:14 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Ming Lei <ming.lei@redhat.com>
Cc:     Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Zhong Jinghua <zhongjinghua@huawei.com>,
        Yu Kuai <yukuai3@huawei.com>, Dennis Zhou <dennis@kernel.org>
Subject: Re: [PATCH 3/3] lib/percpu-refcount: drain ->release() in
 perpcu_ref_exit()
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References: <20221214025101.1268437-1-ming.lei@redhat.com>
 <20221214025101.1268437-4-ming.lei@redhat.com>
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On Wed, Dec 14, 2022 at 10:51:01AM +0800, Ming Lei wrote:
> The pattern of wait_event(percpu_ref_is_zero()) has been used in several
> kernel components, and this way actually has the following risk:

I'd much rather see those components updated to wait for notification from
->release rather than doing this or update percpu_ref_is_zero() to wait for
->release() to finish.

Thanks.

-- 
tejun