From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Hurley <peter@hurleysoftware.com>
Subject: Re: [PATCH] drm/vblank: Fixup and document timestamp
 update/read barriers
Date: Thu, 16 Apr 2015 08:30:55 -0400
Message-ID: <552FAB7F.4040707@hurleysoftware.com>
References: <1429082222-20820-1-git-send-email-daniel.vetter@ffwll.ch>
 <552E60D4.3070307@hurleysoftware.com>
 <20150415173153.GA6092@phenom.ffwll.local>
Mime-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: base64
Return-path: <intel-gfx-bounces@lists.freedesktop.org>
In-Reply-To: <20150415173153.GA6092@phenom.ffwll.local>
List-Unsubscribe: <http://lists.freedesktop.org/mailman/options/intel-gfx>,
 <mailto:intel-gfx-request@lists.freedesktop.org?subject=unsubscribe>
List-Archive: <http://lists.freedesktop.org/archives/intel-gfx>
List-Post: <mailto:intel-gfx@lists.freedesktop.org>
List-Help: <mailto:intel-gfx-request@lists.freedesktop.org?subject=help>
List-Subscribe: <http://lists.freedesktop.org/mailman/listinfo/intel-gfx>,
 <mailto:intel-gfx-request@lists.freedesktop.org?subject=subscribe>
Errors-To: intel-gfx-bounces@lists.freedesktop.org
Sender: "Intel-gfx" <intel-gfx-bounces@lists.freedesktop.org>
To: Daniel Vetter <daniel@ffwll.ch>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>, Intel Graphics Development <intel-gfx@lists.freedesktop.org>, =?UTF-8?B?TWljaGVsIETDpG56ZXI=?= <michel@daenzer.net>, DRI Development <dri-devel@lists.freedesktop.org>, Daniel Vetter <daniel.vetter@intel.com>
List-Id: dri-devel@lists.freedesktop.org
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