From: Trond Myklebust <trondmy@primarydata.com>
To: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
CC: Schumaker Anna <anna.schumaker@netapp.com>,
        List Linux NFS Mailing <linux-nfs@vger.kernel.org>,
        List Linux Kernel Mailing <linux-kernel@vger.kernel.org>,
        "tglx@linutronix.de" <tglx@linutronix.de>
Subject: Re: [PATCH v3] NFSv4: replace seqcount_t with a rw_semaphore
Date: Mon, 31 Oct 2016 15:30:02 +0000
Message-ID: <51E3F753-2D1F-4370-BFEB-BD8356D622A1@primarydata.com>
References: <20161021164727.24485-1-bigeasy@linutronix.de>
 <20161028210511.k7hrsfxovti7gqtu@linutronix.de>
 <747E2CCB-3D83-40FD-8B31-46AB5A5E8592@primarydata.com>
 <20161031131958.mrrez5t7sow75p6v@linutronix.de>
In-Reply-To: <20161031131958.mrrez5t7sow75p6v@linutronix.de>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Sender: linux-nfs-owner@vger.kernel.org
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