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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id C2424EF99D3 for ; Fri, 13 Feb 2026 20:50:50 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 115CD10E318; Fri, 13 Feb 2026 20:50:50 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="U86ZdOsn"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.19]) by gabe.freedesktop.org (Postfix) with ESMTPS id 7587310E2C2 for ; Fri, 13 Feb 2026 20:50:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1771015849; x=1802551849; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=oJroJAfUCzANXKRjF+wS9nbNdxeXx8dNj1BOK4YDmfw=; b=U86ZdOsn8Vds3mW6odRbVFL42dON5on7YGeFkwckOMA9pzwY4kXIyIRE SXDn5LnTc9YauBq0aJtFnGvmS63+VXrT5ts2/WFB5qNcA1ulsAOM14TA7 UVfNo/LBDio/zSv7t1nz9T8+3z7V6YxeHQ6zBIjP/D5IpWlDxFhPK5U3O B9VugCgvMtj9AYuWJp1GvMxPRe540kgxJuXvMPZdoF3m7VWGQUYEa7Lti ducrwHoldRX+5UvipxndHhZUIo//5BSZvR4Rh4xjO4JFqo9pM2BLFWJev iCr18upN7QLcJpCxXLMQRYZJbO1Ol2vyoC/Myjl+aRoiNYz9ntYbF5OXg Q==; X-CSE-ConnectionGUID: adoZIqW8TbOSMr4RhWkLuQ== X-CSE-MsgGUID: 4e+UgHAyQRybC/7SzeqHQg== X-IronPort-AV: E=McAfee;i="6800,10657,11700"; a="72109735" X-IronPort-AV: E=Sophos;i="6.21,289,1763452800"; d="scan'208";a="72109735" Received: from fmviesa010.fm.intel.com ([10.60.135.150]) by orvoesa111.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Feb 2026 12:50:48 -0800 X-CSE-ConnectionGUID: PUOVIsjPRf2PFloFl7wIjA== X-CSE-MsgGUID: qeXbabCUQdmoOc2Z8toyTg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,289,1763452800"; d="scan'208";a="212131361" Received: from lstrano-desk.jf.intel.com ([10.54.39.91]) by fmviesa010-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Feb 2026 12:50:47 -0800 From: Matthew Brost To: intel-xe@lists.freedesktop.org Cc: francois.dugast@intel.com, daniele.ceraolospurio@intel.com, michal.wajdeczko@intel.com Subject: [PATCH 0/2] GuC CT memory optimizations Date: Fri, 13 Feb 2026 12:50:41 -0800 Message-Id: <20260213205043.3111176-1-matthew.brost@intel.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" Profiling has shown that reading from VRAM on BMG is very slow and introduces significant latency in GuC CT operations. To address this, CPU-side read buffers (G2H) are moved to system memory, and unnecessary CPU reads of VRAM in hot paths are removed. This is marked as a fixes change due to the dramatic improvement in G2H performance, which affects hot paths such as TLB invalidation fences and fault-storm handling. We likely have similar issues in hardware fence signaling paths that currently read from VRAM. A follow-up will move the LRC fence seqno (and possibly other CPU-side LRC reads) to system memory as well. Matt Matthew Brost (2): drm/xe: Split H2G and G2H into separate buffer objects drm/xe: Remove H2G reads in CT send path in non-debug builds drivers/gpu/drm/xe/xe_guc_ct.c | 80 ++++++++++++++++++---------- drivers/gpu/drm/xe/xe_guc_ct_types.h | 6 ++- 2 files changed, 55 insertions(+), 31 deletions(-) -- 2.34.1