From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7DDB7C4361B for ; Thu, 10 Dec 2020 21:57:22 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0D0B423DE3 for ; Thu, 10 Dec 2020 21:57:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0D0B423DE3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 7CB2C6EB6C; Thu, 10 Dec 2020 21:57:21 +0000 (UTC) Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by gabe.freedesktop.org (Postfix) with ESMTPS id 22DF26EB6C for ; Thu, 10 Dec 2020 21:57:20 +0000 (UTC) IronPort-SDR: MzY7roNxZpFJcvTncLCcWJGISiFVMkh1/AwmLwmcB/C4g1a8NMGEeCO7XmKIjxDVqtiAZne6Uk XtRfZWHH2lFA== X-IronPort-AV: E=McAfee;i="6000,8403,9831"; a="174453981" X-IronPort-AV: E=Sophos;i="5.78,409,1599548400"; d="scan'208";a="174453981" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Dec 2020 13:57:19 -0800 IronPort-SDR: CHw6SLzRgbv6saUWep//BQLjmolkAcleW+DMebygiPlW5mnUxIGpvggY+yL/BSspJonBXzG7wS YUhy6CcRwsuA== X-IronPort-AV: E=Sophos;i="5.78,409,1599548400"; d="scan'208";a="378328886" Received: from unknown (HELO sdutt-i7) ([10.165.21.147]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Dec 2020 13:57:19 -0800 Date: Thu, 10 Dec 2020 13:51:33 -0800 From: Matthew Brost To: Chris Wilson Message-ID: <20201210215133.GB25383@sdutt-i7> References: <20201210080240.24529-1-chris@chris-wilson.co.uk> <20201210080240.24529-19-chris@chris-wilson.co.uk> <20201210191644.GA6255@sdutt-i7> <160763434489.21588.6583586596864510610@build.alporthouse.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <160763434489.21588.6583586596864510610@build.alporthouse.com> User-Agent: Mutt/1.9.4 (2018-02-28) Subject: Re: [Intel-gfx] [PATCH 19/21] drm/i915/gt: Use indices for writing into relative timelines X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: intel-gfx@lists.freedesktop.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Thu, Dec 10, 2020 at 09:05:44PM +0000, Chris Wilson wrote: > Quoting Matthew Brost (2020-12-10 19:16:44) > > On Thu, Dec 10, 2020 at 08:02:38AM +0000, Chris Wilson wrote: > > > Relative timelines are relative to either the global or per-process > > > HWSP, and so we can replace the absolute addressing with store-index > > > variants for position invariance. > > > > > > > Can you explain the benifit of relative addressing? Why can't we also > > use absolute? If we can always use absolute, I don't see the point > > complicating the breadcrumb code. > > It basically allows a third party to move the contexts between hosts > with far less patching of global state. They want us to avoid all fixed > GGTT addressing. > > The breadcrumbs themselves do not notice at all, it's just the timeline > setup and decision to take advantage of the relative commands. The > breadcrumb patches in this series are some outstanding fixes from ~6 > months ago. By breadcrumbs, I meant the emit code. Relative addressing for GVT makes sense. With that, for this patch: Reviewed-by: Matthew Brost > -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx