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 3B2B0D6E2AA for ; Thu, 18 Dec 2025 15:35:32 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id CB36910E950; Thu, 18 Dec 2025 15:35:31 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="iCKpN6Zw"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.17]) by gabe.freedesktop.org (Postfix) with ESMTPS id 5C6DB10E84E for ; Thu, 18 Dec 2025 15:35:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1766072130; x=1797608130; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=kbHKWIOBGfvNsy1WP9+WqzCst0+VhUcKfY282xDBwjk=; b=iCKpN6ZwznKPHc4Xbczyr54ObqHGQwcj4QO6/Sq//cckE/VFRziAf3Vh aF0bvtjmjgGFRqRn6fYJAJW0DMosH87SRCKS3E4wC6+c44OcJ2bPVrNXZ 7LTV5HHBKmaVaOezMvwB0OxonPMuLWXjjMW0otvmTm61gRuAZgQ5JXl0k o4AYBbGX4MW7rgRTpvbBMywRnF5kwvIR/qAKf2KkG2cLgLy3FqEkQr6t/ 4I1e5UKE3wFe8LSvgGwiwNfVQhZI8lCCEiE7XB6vp8PLjqShKP+tHl+0S 6Yg21kORns/91ORPIMmFk5WFXzrGXXQ+Tf9PhQ0lVPxNqeDazFeqyk5Vr g==; X-CSE-ConnectionGUID: HyHxQqARSJeolilg1Lvs9w== X-CSE-MsgGUID: VR5463tFTqaGQPV51gGuuw== X-IronPort-AV: E=McAfee;i="6800,10657,11646"; a="67906270" X-IronPort-AV: E=Sophos;i="6.21,158,1763452800"; d="scan'208";a="67906270" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by fmvoesa111.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Dec 2025 07:35:30 -0800 X-CSE-ConnectionGUID: PDtSLPTTT5ubG17dHHn+BQ== X-CSE-MsgGUID: tpVQAt0USTe6tdjBSLFrBw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,158,1763452800"; d="scan'208";a="236042214" Received: from dut4086lnl.fm.intel.com ([10.105.10.207]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Dec 2025 07:35:29 -0800 From: Jonathan Cavitt To: intel-xe@lists.freedesktop.org Cc: saurabhg.gupta@intel.com, alex.zuo@intel.com, jonathan.cavitt@intel.com, matthew.brost@intel.com, daniele.ceraolospurio@intel.com, rodrigo.vivi@intel.com, michal.wajdeczko@intel.com Subject: [PATCH 0/6] drm/xe/xe_guc_ct: Prevent compiler read/write optimization breaks Date: Thu, 18 Dec 2025 15:35:28 +0000 Message-ID: <20251218153527.6436-8-jonathan.cavitt@intel.com> X-Mailer: git-send-email 2.43.0 MIME-Version: 1.0 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" Use READ_ONCE and WRITE_ONCE when operating on ct->state and the g2h_fence->done values to prevent the compiler from ignoring these necessary operations. v2: (Matt Brost) - Add Fixes tags - Add comments v3: - Split into multiple patches (Rodrigo Vivi) Suggested-by: Matthew Brost Suggested-by: Rodrigo Vivi Signed-off-by: Jonathan Cavitt Cc: Daniele Ceraolo Spurio Cc: Rodrigo Vivi Cc: Michal Wajdeczko Jonathan Cavitt (6): drm/xe/xe_guc_ct: WRITE_ONCE g2h_fence done in g2h_fence_cancel drm/xe/xe_guc_ct: WRITE_ONCE g2h_fence done in parse_g2h_response drm/xe/xe_guc_ct: WRITE_ONCE ct state in guc_ct_change_state drm/xe/xe_guc_ct: READ_ONCE ct state in xe_guc_ct_initialized drm/xe/xe_guc_ct: READ_ONCE ct state in xe_guc_ct_enabled drm/xe/xe_guc_ct: Justify WRITE_ONCE/READ_ONCE usage drivers/gpu/drm/xe/xe_guc_ct.c | 14 +++++++++++--- drivers/gpu/drm/xe/xe_guc_ct.h | 6 ++++-- 2 files changed, 15 insertions(+), 5 deletions(-) -- 2.43.0