From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Wilson Subject: Re: patches for occlusion query fix on sandybridge Date: Tue, 14 Dec 2010 21:47:45 +0000 Message-ID: References: <1292302562-5800-1-git-send-email-zhenyuw@linux.intel.com> <877hfcgrrx.fsf@pollan.anholt.net> <944877732.20101214205909@ntlworld.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by gabe.freedesktop.org (Postfix) with ESMTP id 120AF9E837 for ; Tue, 14 Dec 2010 13:47:48 -0800 (PST) In-Reply-To: <944877732.20101214205909@ntlworld.com> 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: david may , Zhenyu Wang , intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org On Tue, 14 Dec 2010 20:59:09 +0000, david may wrote: > Hello Eric, > > Tuesday, December 14, 2010, 5:58:58 PM, you wrote: > > > Why don't we just keep all of our BOs LLC cached? This was supposed to > > be a big win of the new chipset, as it means we don't need to clflush. > > Ohh,the implication here is that people are/have been writing the > code,But Not bothering Actually benching/Profiling it to see if it actually is faster and > better throughput than before, that seems wrong, especially given sandy bridge is > supposed to be better, i Do Hope you are/will be testing/benching/Profiling > to see if it/all SB Code is actually "a big win" one way or the other before passing for > release. No, the default on SNB was changed back to uncached in order to fix some coherency issues in the short term. Correctness first. commit 8d0f56708292ca5c256ee3b7187d124afee81d93 Author: Zhenyu Wang Date: Tue Nov 2 17:30:47 2010 +0800 agp/intel: restore cache behavior on sandybridge This restores cache behavior for default AGP_USER_MEMORY as uncached, and leave default AGP_USER_CACHED_MEMORY as LLC only. I've seen different cache behavior on one sandybridge desktop CPU vs. another mobile CPU. Until we figure out how to detect the real cache config, restore back to the original behavior now. -Chris -- Chris Wilson, Intel Open Source Technology Centre