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Date:   Wed, 11 Mar 2020 19:29:48 -0700
From:   Matthew Wilcox <willy@infradead.org>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     Jules Irenge <jbi.octave@gmail.com>, boqun.feng@gmail.com,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/1] backing-dev: refactor wb_congested_put()
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 <20200311175919.30523d55b2e5307ba22bbdc0@linux-foundation.org>
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On Wed, Mar 11, 2020 at 05:59:19PM -0700, Andrew Morton wrote:
> hm, it's hard to get excited over this.  Open-coding the
> refcount_dec_and_lock_irqsave() internals at a callsite in order to
> make sparse happy.
> 
> Is there some other way, using __acquires (for example)?

sparse is really bad at conditional lock acquisition.  we have similar
problems over the vfs.  but we shouldn't be obfuscating our code to make
the tool happy.