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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 33719C2BA2B for ; Mon, 13 Apr 2020 20:58:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 188CD20644 for ; Mon, 13 Apr 2020 20:58:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733303AbgDMU6Y (ORCPT ); Mon, 13 Apr 2020 16:58:24 -0400 Received: from mga17.intel.com ([192.55.52.151]:8591 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727121AbgDMU6W (ORCPT ); Mon, 13 Apr 2020 16:58:22 -0400 IronPort-SDR: QYuP59TDzcZMn+8VjanUFqBbPqGzm6ycl4IAn+R1Lp5WuZQ2zMJ78LCme4POGFGXQTqmHsa7fK dWBGnggPLhtA== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Apr 2020 13:58:21 -0700 IronPort-SDR: oa1YgajQmXRj8z50iScEKqqdsdg8+wY7nIw2YG5BQhw+6QTuhRz7hr/FkrOca5h8bNqpZbim3H LPbyCrmgZFeQ== X-IronPort-AV: E=Sophos;i="5.72,380,1580803200"; d="scan'208";a="453301654" Received: from rchatre-s.jf.intel.com ([10.54.70.76]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Apr 2020 13:58:20 -0700 From: Reinette Chatre To: tglx@linutronix.de, fenghua.yu@intel.com, bp@alien8.de, tony.luck@intel.com Cc: kuo-lang.tseng@intel.com, ravi.v.shankar@intel.com, mingo@redhat.com, babu.moger@amd.com, hpa@zytor.com, x86@kernel.org, linux-kernel@vger.kernel.org, Reinette Chatre Subject: [PATCH V2 0/4] x86/resctrl: Enable user to view and select thread throttling mode Date: Mon, 13 Apr 2020 13:57:59 -0700 Message-Id: X-Mailer: git-send-email 2.21.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org V1 upstream submission available from: https://lore.kernel.org/lkml/cover.1585765499.git.reinette.chatre@intel.com A notable change since V1 is the inclusion of two additional patches from Fenghua Yu that introduce the new per-thread MBA feature. These changes are added to this series because they are small and closely related to the original submission. The per-thread MBA feature is a hardware advancement that requires no software interface changes. The patches added just enumerate the feature and expose it to userspace by showing "per-thread" in the new resctrl file "thread_throttle_mode" to help user applications fine tune performance. There are currently a few resctrl changes outstanding for upstream inclusion. To support their consideration all outstanding resctrl patches can be viewed at https://github.com/rchatre/linux.git (branch resctrl/next) Changes since V1 (also documented within patches to which they apply): - Rebased on top of James Morse's CDP fix (https://lore.kernel.org/lkml/20200221162105.154163-1-james.morse@arm.com) - Remove RF_UNINITIALIZED (having uninitialized be represented with ones creates too much confusion), replace with an explicit check of rft->fflags in rdtgroup_add_files() (Fenghua Yu) - Rename MBA_THREAD_THROTTLE_MODE to MBA_THROTTLE_MODE_MASK to clarify its use as a mask (Tony Luck) - Introduce explicit MBA_THROTTLE_MODE_MAX instead of implying it is the opposite of min and use these values (min and max) explicitly whenever testing/setting the throttle mode value (Tony Luck) - Add __init attribute to thread_throttle_mode_init_intel_rw() and thread_throttle_mode_init_intel_ro() since they are only needed during initialization (Fenghua Yu) - Remove MBA_CFG MSR reads and error checking so that the patch is simpler and easier to review (Fenghua Yu) - Ensure CPU hotplug lock is taken when writing register on multiple CPUs (Fenghua Yu) - Use CPU mask already maintained as part of domains to determine which CPUs to update MBA register on (Fenghua Yu) - Maintain MBA configuration register contents to support use case when not all CPUs of a package are online when configuration is set from user space - Use seq_puts() instead of seq_printf() when simple strings are printed - Set MBA configuration to default when resctrl is unmounted - Complete rewrite of "thread_throttle_mode" documentation (Tony Luck) - Remove unnecessary checks on user input (Andy Shevchenko) - Change code style surrounding usage of sysfs_match_string() (Andy Shevchenko) >From V1 submission: The first patch in this series introduces a new resctrl file, "thread_throttle_mode", on Intel systems that exposes to the user how per-thread values are allocated to a core. This is added in support of newer Intel systems that can be configured to allocate either maximum or minimum throttling of the per-thread CLOS values to the core. Details about the feature can be found in the commit description and in Chapter 9 of the most recent Intel ISE available from https://software.intel.com/sites/default/files/managed/c5/15/architecture-instruction-set-extensions-programming-reference.pdf The first patch parses user input with the appropriate sysfs API that has not previously been used in resctrl. The second (in V2 the fourth) patch is added as a subsequent cleanup that switches existing resctrl string parsing code to also use this appropriate API. Fenghua Yu (2): x86/resctrl: Enumerate per-thread MBA x86/resctrl: Enable per-thread MBA Reinette Chatre (2): x86/resctrl: Enable user to view and select thread throttling mode x86/resctrl: Use appropriate API for strings terminated by newline Documentation/x86/resctrl_ui.rst | 16 +- arch/x86/include/asm/cpufeatures.h | 1 + arch/x86/kernel/cpu/cpuid-deps.c | 1 + arch/x86/kernel/cpu/resctrl/core.c | 32 ++++ arch/x86/kernel/cpu/resctrl/internal.h | 13 ++ arch/x86/kernel/cpu/resctrl/rdtgroup.c | 231 +++++++++++++++++++++++-- arch/x86/kernel/cpu/scattered.c | 1 + 7 files changed, 277 insertions(+), 18 deletions(-) -- 2.21.0