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 58B40C55165 for ; Thu, 30 Jul 2026 23:36:08 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1534410F0FF; Thu, 30 Jul 2026 23:36:08 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="ZL+01JHP"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) by gabe.freedesktop.org (Postfix) with ESMTPS id 39F9110F0EE for ; Thu, 30 Jul 2026 23:35:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1785454553; x=1816990553; h=from:to:subject:date:message-id:mime-version: content-transfer-encoding; bh=4CSyntgchm9a4rUctlonCpzyDZMNPMmL96gR8jJiwJE=; b=ZL+01JHPWNSGOXFDR47y+hx3txCdaSgWdNh2Opy98GmAf4pU8v2/jljK +o4DDQ0/cBpntZuvQ70SmRlDCuMv56W0rtx5mtFLlkk6n1LYQEAkqomSO CCnKfSR/zPVOVdpMCPheFLTwQqOf1JDBwTCyiGYkEym+QOnq8i6MHDMCJ tqf/yDc+90ATl8gq/w8ABQPlqF09RiXtBzGKUpjCVhLIixY5hPWAL4YbI L7c1TUvJ8ZEGCXn7ZUIc49LHs56QHts5UREo/HOKabF8S9bPrQbPaHmdg c4JiTzsCmskH3VDnw1N+GxXgggPuxe6JBQqNXCrxb5T04FcUAORVlMt+R A==; X-CSE-ConnectionGUID: 7cPNky3FQxyHqOgR7ht1WQ== X-CSE-MsgGUID: Lk7fnh9lTK6mQf8A+qMhiA== X-IronPort-AV: E=McAfee;i="6800,10657,11860"; a="103619702" X-IronPort-AV: E=Sophos;i="6.25,195,1779174000"; d="scan'208";a="103619702" Received: from fmviesa008.fm.intel.com ([10.60.135.148]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jul 2026 16:35:53 -0700 X-CSE-ConnectionGUID: fFaBOVVsTLWRLymMb8mk3A== X-CSE-MsgGUID: a9phRKqNSWeGDbMacbFiZw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,195,1779174000"; d="scan'208";a="257759653" Received: from orsosgc001.jf.intel.com ([10.88.27.185]) by fmviesa008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jul 2026 16:35:52 -0700 From: Umesh Nerlige Ramappa To: intel-xe@lists.freedesktop.org, Ashutosh Dixit Subject: [PATCH 0/3] Modify the SW tail logic in OA Date: Thu, 30 Jul 2026 16:35:40 -0700 Message-ID: <20260730233539.3140839-5-umesh.nerlige.ramappa@intel.com> X-Mailer: git-send-email 2.51.0 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" OA unit updates the HW TAIL register to indicate that a new report is available, although it does not guarantee that the report is visible in memory. Also the currently running workload contributes to some latency in seeing this report in memory. In the past we would set some fields in the OA report and check if the fields are populated to non-zero values by the HW, but this is no longer sufficient since some parts of the report may land out of order under heavy workloads. Drop this WA and add a new logic that just waits for a fixed number of HW TAIL report increments before returning data to the user. User will always see the reports lagging by this fixed number, however we do not have realtime use cases for OAG since OAG reports are mainly post processed. v2: Rebase v3: Add Sashiko's review comments Signed-off-by: Umesh Nerlige Ramappa Umesh Nerlige Ramappa (3): drm/xe/xe_oa: Clear status only if relevant bits are set drm/xe/xe_oa: Avoid checking and setting fields in the OA report drm/xe/xe_oa: Add a lag to the reports that is exported to user drivers/gpu/drm/xe/xe_oa.c | 94 +++++--------------------------------- 1 file changed, 12 insertions(+), 82 deletions(-) -- 2.51.0