From patchwork Tue Nov 14 04:01:06 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yicong Yang X-Patchwork-Id: 13454758 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 301B1C4167D for ; Tue, 14 Nov 2023 04:05:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:Subject:CC :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=agxv1i7u1GkCEljgbweZBQrIpran2XW0gMQB+Pc82OA=; b=uf6U5S5f9I1MJp n1iH6DcGpQluJ4Vsty5uRT9fH09eahjzPbeZF8POu3FsfECYB1GCFi9KLerW2hKS4Kn75v/p3ifDq KE/KUOSZEN3XaC4WneuQNjkn3z9zu5q/h2ZhKC5TxISmXPY2nZg15vtYo6NuXeUxAvm1zHkt1Ohxb dl5fkci0zHkcqmok5AuNktR1KIJpiOdCIPnjAFlEYlOXZ/1KC6KgfMyMWIhsV8NqD8aNERjcunoxV ZYnjaAcEt0DJoGVANqlI2EK/5S3LWphio5nkKWJQ6bh6cTKh/6dlPqG893Y8ohQoxHLhDvcaqXjCY PZxEsQTam8lTOsVtiPMg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1r2kfM-00F8Df-27; Tue, 14 Nov 2023 04:04:44 +0000 Received: from szxga08-in.huawei.com ([45.249.212.255]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1r2kfI-00F8Ab-0J for linux-arm-kernel@lists.infradead.org; Tue, 14 Nov 2023 04:04:41 +0000 Received: from canpemm500009.china.huawei.com (unknown [172.30.72.54]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4STszP4LPsz1P8JJ; Tue, 14 Nov 2023 12:01:05 +0800 (CST) Received: from localhost.localdomain (10.50.165.33) by canpemm500009.china.huawei.com (7.192.105.203) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Tue, 14 Nov 2023 12:04:23 +0800 From: Yicong Yang To: , , , CC: , , , , , , , Subject: [PATCH v3 0/4] Support SMT control on arm64 Date: Tue, 14 Nov 2023 12:01:06 +0800 Message-ID: <20231114040110.54590-1-yangyicong@huawei.com> X-Mailer: git-send-email 2.31.0 MIME-Version: 1.0 X-Originating-IP: [10.50.165.33] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To canpemm500009.china.huawei.com (7.192.105.203) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231113_200440_317476_8D262A50 X-CRM114-Status: UNSURE ( 8.29 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Yicong Yang The core CPU control framework supports runtime SMT control which is not yet supported on arm64. Besides the general vulnerabilities concerns we want this runtime control on our arm64 server for: - better single CPU performance in some cases - saving overall power consumption This patchset implements it in the following aspects: - implements the basic support in arch_topology driver - support retrieve SMT thread number on OF based system - support retrieve SMT thread number on ACPI based system - select HOTPLUG_SMT for arm64 Tests has been done on our real ACPI based arm64 server and on ACPI/OF based QEMU VMs. The patchset is based on v6.7-rc1. Change since v2: - Detect SMT thread number at topology build from ACPI/DT, avoid looping CPUs - Split patches into ACPI/OF/arch_topology path and enable the kconfig for arm64 Link: https://lore.kernel.org/linux-arm-kernel/20231010115335.13862-1-yangyicong@huawei.com/ Yicong Yang (4): arch_topology: Support basic SMT control for the driver arch_topology: Support SMT control for OF based system arm64: topology: Support SMT control on ACPI based system arm64: Kconfig: Enable HOTPLUG_SMT arch/arm64/Kconfig | 1 + arch/arm64/kernel/topology.c | 23 +++++++++++++++++++++ drivers/base/arch_topology.c | 39 +++++++++++++++++++++++++++++++++++ include/linux/arch_topology.h | 9 ++++++++ 4 files changed, 72 insertions(+)