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 4AF2CD13570 for ; Mon, 28 Oct 2024 10:52:06 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id CF55B10E474; Mon, 28 Oct 2024 10:52:05 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="uxkUIF3M"; dkim-atps=neutral Received: from nyc.source.kernel.org (nyc.source.kernel.org [147.75.193.91]) by gabe.freedesktop.org (Postfix) with ESMTPS id F3C5410E473; Mon, 28 Oct 2024 10:52:03 +0000 (UTC) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id 002A4A41BF8; Mon, 28 Oct 2024 10:50:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B0FF2C4CEE3; Mon, 28 Oct 2024 10:52:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1730112722; bh=6Qno+30D6RM+lx+mo3VjfYuDM+GRGmcC8S24sQmYI+M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uxkUIF3Msw93nLh4g27+txK3Ti+BJCEyhnhljycGQH4ze8+OcAIvcdm2ZS120OXBo N8QslyB+MNovnHOe54kf20MCHOFqh/0/KYETSG4RUi5BZ7nI03tqrp4mcXmLf8FHuZ yyGzeRm5JIhjqkn2VhI9PFo3KaMKs9Jcupfjkz5DCOaNHmuuDblpdrE4cLEqt/eNMS xDCGNYpMlhk10MQERk40fvPIi4Cjg6D9eaoN36JCm29kvauChxulkdLkyOrEUPr8nw CQsItBrd8hskFvFftoaJt0f86O9vhz14smVViJ4vpVWrmNU1JmsW0biQ8Xb44zM3j2 a+CpltRU05s9A== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Badal Nilawar , Matthew Brost , Matthew Auld , John Harrison , Himal Prasad Ghimiray , Lucas De Marchi , Sasha Levin , thomas.hellstrom@linux.intel.com, rodrigo.vivi@intel.com, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, airlied@gmail.com, simona@ffwll.ch, intel-xe@lists.freedesktop.org, dri-devel@lists.freedesktop.org Subject: [PATCH AUTOSEL 6.11 29/32] drm/xe/guc/ct: Flush g2h worker in case of g2h response timeout Date: Mon, 28 Oct 2024 06:50:11 -0400 Message-ID: <20241028105050.3559169-29-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20241028105050.3559169-1-sashal@kernel.org> References: <20241028105050.3559169-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.11.5 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" From: Badal Nilawar [ Upstream commit 22ef43c78647dd37b0dafe2182b8650b99dbbe59 ] In case if g2h worker doesn't get opportunity to within specified timeout delay then flush the g2h worker explicitly. v2: - Describe change in the comment and add TODO (Matt B/John H) - Add xe_gt_warn on fence done after G2H flush (John H) v3: - Updated the comment with root cause - Clean up xe_gt_warn message (John H) Closes: https://gitlab.freedesktop.org/drm/xe/kernel/issues/1620 Closes: https://gitlab.freedesktop.org/drm/xe/kernel/issues/2902 Signed-off-by: Badal Nilawar Cc: Matthew Brost Cc: Matthew Auld Cc: John Harrison Cc: Himal Prasad Ghimiray Reviewed-by: Himal Prasad Ghimiray Acked-by: Matthew Brost Signed-off-by: Matthew Brost Link: https://patchwork.freedesktop.org/patch/msgid/20241017111410.2553784-2-badal.nilawar@intel.com (cherry picked from commit e5152723380404acb8175e0777b1cea57f319a01) Signed-off-by: Lucas De Marchi Signed-off-by: Sasha Levin --- drivers/gpu/drm/xe/xe_guc_ct.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/drivers/gpu/drm/xe/xe_guc_ct.c b/drivers/gpu/drm/xe/xe_guc_ct.c index cd9918e3896c0..ab24053f8766f 100644 --- a/drivers/gpu/drm/xe/xe_guc_ct.c +++ b/drivers/gpu/drm/xe/xe_guc_ct.c @@ -888,6 +888,24 @@ static int guc_ct_send_recv(struct xe_guc_ct *ct, const u32 *action, u32 len, ret = wait_event_timeout(ct->g2h_fence_wq, g2h_fence.done, HZ); + /* + * Occasionally it is seen that the G2H worker starts running after a delay of more than + * a second even after being queued and activated by the Linux workqueue subsystem. This + * leads to G2H timeout error. The root cause of issue lies with scheduling latency of + * Lunarlake Hybrid CPU. Issue dissappears if we disable Lunarlake atom cores from BIOS + * and this is beyond xe kmd. + * + * TODO: Drop this change once workqueue scheduling delay issue is fixed on LNL Hybrid CPU. + */ + if (!ret) { + flush_work(&ct->g2h_worker); + if (g2h_fence.done) { + xe_gt_warn(gt, "G2H fence %u, action %04x, done\n", + g2h_fence.seqno, action[0]); + ret = 1; + } + } + /* * Ensure we serialize with completion side to prevent UAF with fence going out of scope on * the stack, since we have no clue if it will fire after the timeout before we can erase -- 2.43.0