From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Wilson Subject: Re: [PATCH] drm/i915: Avoid using mappable space for relocation processing through the CPU Date: Mon, 26 Mar 2012 09:32:52 +0100 Message-ID: <1332750777_96879@CP5-2952> References: <1332749427-2729-1-git-send-email-daniel.vetter@ffwll.ch> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from fireflyinternet.com (smtp.fireflyinternet.com [109.228.6.236]) by gabe.freedesktop.org (Postfix) with ESMTP id 30D1F9EB5D for ; Mon, 26 Mar 2012 01:33:04 -0700 (PDT) In-Reply-To: <1332749427-2729-1-git-send-email-daniel.vetter@ffwll.ch> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: Daniel Vetter , Intel Graphics Development List-Id: intel-gfx@lists.freedesktop.org On Mon, 26 Mar 2012 10:10:27 +0200, Daniel Vetter wrote: > From: Chris Wilson > > We try to avoid writing the relocations through the uncached GTT, if the > buffer is currently in the CPU write domain and so will be flushed out to > main memory afterwards anyway. Also on SandyBridge we can safely write > to the pages in cacheable memory, so long as the buffer is LLC mapped. > In either of these caches, we therefore do not need to force the s/caches/cases/ > reallocation of the buffer into the mappable region of the GTT, reducing > the aperture pressure. -Chris -- Chris Wilson, Intel Open Source Technology Centre