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Date: Fri, 29 Dec 2017 02:04:18 -0800
From: Christoph Hellwig <hch@infradead.org>
To: Tejun Heo <tj@kernel.org>
Cc: jack@suse.cz, axboe@kernel.dk, clm@fb.com, jbacik@fb.com,
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        jianchao.w.wang@oracle.com, Bart.VanAssche@wdc.com
Subject: Re: [PATCH 1/7] blk-mq: protect completion path with RCU
Message-ID: <20171229100418.GB4020@infradead.org>
References: <20171216120726.517153-1-tj@kernel.org>
 <20171216120726.517153-2-tj@kernel.org>
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Why do you need the srcu protection?  The completion path can never
sleep.

If there is a good reason to keep it please add commment, and
make the srcu variant a separate function only used by drivers that
need it instead of adding the conditional.