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From:   David Howells <dhowells@redhat.com>
In-Reply-To: <20181017151134.GA8966@andrea>
References: <20181017151134.GA8966@andrea> <153978619457.8478.3813964117489247515.stgit@warthog.procyon.org.uk> <153978621809.8478.2198040871218302573.stgit@warthog.procyon.org.uk>
To:     Andrea Parri <andrea.parri@amarulasolutions.com>
Cc:     dhowells@redhat.com, gregkh@linux-foundation.org,
        Kiran Kumar Modukuri <kiran.modukuri@gmail.com>,
        viro@zeniv.linux.org.uk, sandeen@redhat.com,
        linux-cachefs@redhat.com, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/4] fscache: Fix race in fscache_op_complete() due to split atomic_sub & read
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Date:   Wed, 17 Oct 2018 16:32:13 +0100
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Andrea Parri <andrea.parri@amarulasolutions.com> wrote:

> > Fix this by using atomic_sub_return() instead of two calls.
> 
> Seems a case for atomic_sub_return_relaxed()... why not?

Ummm...  In that case, should it be atomic_sub_return_release()?

David