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From:   David Howells <dhowells@redhat.com>
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To:     Oleg Nesterov <oleg@redhat.com>
Cc:     dhowells@redhat.com, Marc Dionne <marc.dionne@auristor.com>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Chuck Lever <chuck.lever@oracle.com>,
        linux-afs@lists.infradead.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] rxrpc_find_service_conn_rcu: use read_seqbegin() rather than read_seqbegin_or_lock()
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Date:   Wed, 01 Nov 2023 21:22:30 +0000
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Oleg Nesterov <oleg@redhat.com> wrote:

> Just none of read_seqbegin_or_lock/need_seqretry/done_seqretry
> helpers make any sense in this code.

I disagree.  I think in at least a couple of cases I do want a locked second
path - ideally locked shared if seqlock can be made to use an rwlock instead
of a spinlock.

David