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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 C275BC54E49 for ; Thu, 7 Mar 2024 07:12:38 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ri7uy-0006iV-09; Thu, 07 Mar 2024 02:11:52 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ri7uv-0006iF-VK for qemu-devel@nongnu.org; Thu, 07 Mar 2024 02:11:49 -0500 Received: from mgamail.intel.com ([192.198.163.9]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ri7ut-00056i-FK for qemu-devel@nongnu.org; Thu, 07 Mar 2024 02:11:49 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1709795507; x=1741331507; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=ptKBtLmmCoH+PWXUbrSU9RR50cWuSb+9x8Ct9YMPEHM=; b=LGZTwM0jvwcxBBudpZhDy2HUPKBgYUWtU+PjDK+g1H785YUQd5wK4bFI GtuzelXuZDf8qBXrn5ek1HgJjdPgbQdiNT0Ss18HXDLvjKWAFyXohnUQr hlA9XUOBnACKAYN+oqzvOf0Z3TgB5n2ZnHq5VUSTfthUtOxWOgnXkr39B HjFFEOIwp5xC2anwTXaQL1nwZu2gIBPUi3t+VNuQJDBrAc1R0OHwn2aWQ 5fcEvmvS44kboIBhwGwWFubsKaSs/5xWcgzD1k5x3yWByVyFVmqYemh5f ua9EMOFxAEjHaUTTsyyp0rfut0Aeix3M05KqF8Y7A1TvhIckXFkjWdW0R Q==; X-IronPort-AV: E=McAfee;i="6600,9927,11005"; a="15171642" X-IronPort-AV: E=Sophos;i="6.06,210,1705392000"; d="scan'208";a="15171642" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by fmvoesa103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Mar 2024 23:11:43 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.06,210,1705392000"; d="scan'208";a="9924109" Received: from liuzhao-optiplex-7080.sh.intel.com (HELO localhost) ([10.239.160.36]) by fmviesa007.fm.intel.com with ESMTP; 06 Mar 2024 23:11:39 -0800 Date: Thu, 7 Mar 2024 15:25:26 +0800 From: Zhao Liu To: Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= Cc: Eduardo Habkost , Marcel Apfelbaum , Yanan Wang , Daniel P =?iso-8859-1?Q?=2E_Berrang=E9?= , Thomas Huth , Igor Mammedov , Prasad Pandit , qemu-devel@nongnu.org, "Michael S. Tsirkin" , Peter Maydell , Alex =?iso-8859-1?Q?Benn=E9e?= , Paolo Bonzini , Markus Armbruster , Xiaoling Song , Zhao Liu Subject: Re: [PATCH 00/14] Cleanup on SMP and its test Message-ID: References: <20240306095407.3058909-1-zhao1.liu@linux.intel.com> <91bf387d-0ca1-4812-a414-591f50151d14@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <91bf387d-0ca1-4812-a414-591f50151d14@linaro.org> Received-SPF: none client-ip=192.198.163.9; envelope-from=zhao1.liu@linux.intel.com; helo=mgamail.intel.com X-Spam_score_int: -23 X-Spam_score: -2.4 X-Spam_bar: -- X-Spam_report: (-2.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.365, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_NONE=0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Hi Philippe, > In a previous community call, Zhao asked us how his work will scale > in the heterogeneous context. > > My first idea is CPUs must belong to a cluster. Thank you for considering this! At present, cluster is a arch-specific topology level used by ARM. So maybe we need call this abstraction as another name not "cluster"? I guess the cluster you mentioned is the cluster device used in TCG, right? I also tried to eliminate differences between cluster devices and the cluster level in CPU topology [1]. My previous proposal introduced a abstract topology device [2]. And all topology specific levels are derived from the underlying topology device, including CPU. I feel like this topology device abstraction seems close to your idea, am I understanding it correctly? ;-) > For machines without > explicit cluster, we could always create the first one. Then -smp > would become a sugar property of the first cluster. Next -smp could > also be sugar property of the next cluster. Could you please explain the above ideas more? It feels we need to split -smp for each cluster. But I'm not sure if sugar property means defining smp-like properties for each cluster. Or is there a command line example? ;-) [1]: https://lore.kernel.org/qemu-devel/20231130144203.2307629-23-zhao1.liu@linux.intel.com/ [2]: https://lore.kernel.org/qemu-devel/20231130144203.2307629-9-zhao1.liu@linux.intel.com/ Thanks, Zhao