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Date:   Tue, 10 Jan 2023 07:49:00 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Tejun Heo <tj@kernel.org>
Cc:     Christoph Hellwig <hch@lst.de>, axboe@kernel.dk,
        josef@toxicpanda.com, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/4] blkcg: Drop unnecessary RCU read [un]locks from
 blkg_conf_prep/finish()
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References: <20230105212432.289569-1-tj@kernel.org> <20230105212432.289569-2-tj@kernel.org> <20230108170240.GA19165@lst.de> <Y7x9t+4EwXFl7OwS@slm.duckdns.org>
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On Mon, Jan 09, 2023 at 10:48:55AM -1000, Tejun Heo wrote:
> Now that all RCU flavors have been combined, holding a spin lock, disabling
> irq, disabling preemption all imply RCU read lock.

Can you write it like this in the commit log, please? 

> I can drop the changes but this actually bothers me. The annotation has been
> broken for a *long* time and nobody noticed. Furthermore, I can't remember a
> time when __acquires/__releases notation caught anything that lockdep
> couldn't trivially and can't even think of a way how it could. AFAICS, these
> annotations don't contribute anything other than preservation of themselves.
> I don't see why we would want to keep them.

People have noticed it.  It just hasn't been a priority as there are
lots of even more problematic things.