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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 98569C1B0F1 for ; Wed, 20 Jun 2018 00:27:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5B78520693 for ; Wed, 20 Jun 2018 00:27:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5B78520693 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=zytor.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754290AbeFTA1a (ORCPT ); Tue, 19 Jun 2018 20:27:30 -0400 Received: from terminus.zytor.com ([198.137.202.136]:44961 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752892AbeFTA10 (ORCPT ); Tue, 19 Jun 2018 20:27:26 -0400 Received: from terminus.zytor.com (localhost [127.0.0.1]) by terminus.zytor.com (8.15.2/8.15.2) with ESMTPS id w5K0RLwB3299759 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Tue, 19 Jun 2018 17:27:22 -0700 Received: (from tipbot@localhost) by terminus.zytor.com (8.15.2/8.15.2/Submit) id w5K0RLiX3299756; Tue, 19 Jun 2018 17:27:21 -0700 Date: Tue, 19 Jun 2018 17:27:21 -0700 X-Authentication-Warning: terminus.zytor.com: tipbot set sender to tipbot@zytor.com using -f From: tip-bot for Reinette Chatre Message-ID: Cc: mingo@kernel.org, reinette.chatre@intel.com, linux-kernel@vger.kernel.org, hpa@zytor.com, tglx@linutronix.de Reply-To: mingo@kernel.org, reinette.chatre@intel.com, linux-kernel@vger.kernel.org, hpa@zytor.com, tglx@linutronix.de In-Reply-To: <59b96030bd839dbc474bbac217f9879e45579e52.1527847599.git.reinette.chatre@intel.com> References: <59b96030bd839dbc474bbac217f9879e45579e52.1527847599.git.reinette.chatre@intel.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/cache] x86/intel_rdt: Add utilities to test pseudo-locked region possibility Git-Commit-ID: f809a8d67ee44cedca6d9acf5b8f6252c108e195 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: f809a8d67ee44cedca6d9acf5b8f6252c108e195 Gitweb: https://git.kernel.org/tip/f809a8d67ee44cedca6d9acf5b8f6252c108e195 Author: Reinette Chatre AuthorDate: Fri, 1 Jun 2018 06:09:20 -0700 Committer: Thomas Gleixner CommitDate: Wed, 20 Jun 2018 00:56:37 +0200 x86/intel_rdt: Add utilities to test pseudo-locked region possibility A pseudo-locked region does not have a class of service associated with it and thus not tracked in the array of control values maintained as part of the domain. Even so, when the user provides a new bitmask for another resource group it needs to be checked for interference with existing pseudo-locked regions. Additionally only one pseudo-locked region can be created in any cache hierarchy. Introduce two utilities in support of above scenarios: (1) a utility that can be used to test if a given capacity bitmask overlaps with any pseudo-locked regions associated with a particular cache instance, (2) a utility that can be used to test if a pseudo-locked region exists within a particular cache hierarchy. Signed-off-by: Reinette Chatre Signed-off-by: Thomas Gleixner Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: vikas.shivappa@linux.intel.com Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: dave.hansen@intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/59b96030bd839dbc474bbac217f9879e45579e52.1527847599.git.reinette.chatre@intel.com --- arch/x86/kernel/cpu/intel_rdt.h | 2 + arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c | 74 +++++++++++++++++++++++++++++ 2 files changed, 76 insertions(+) diff --git a/arch/x86/kernel/cpu/intel_rdt.h b/arch/x86/kernel/cpu/intel_rdt.h index 12b006178d3a..119645c83e27 100644 --- a/arch/x86/kernel/cpu/intel_rdt.h +++ b/arch/x86/kernel/cpu/intel_rdt.h @@ -503,6 +503,8 @@ enum rdtgrp_mode rdtgroup_mode_by_closid(int closid); int rdtgroup_tasks_assigned(struct rdtgroup *r); int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp); int rdtgroup_locksetup_exit(struct rdtgroup *rdtgrp); +bool rdtgroup_cbm_overlaps_pseudo_locked(struct rdt_domain *d, u32 _cbm); +bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_domain *d); struct rdt_domain *get_domain_from_cpu(int cpu, struct rdt_resource *r); int update_domains(struct rdt_resource *r, int closid); void closid_free(int closid); diff --git a/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c b/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c index ce8243c87877..b145a7386b10 100644 --- a/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c +++ b/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c @@ -299,3 +299,77 @@ int rdtgroup_locksetup_exit(struct rdtgroup *rdtgrp) pseudo_lock_free(rdtgrp); return 0; } + +/** + * rdtgroup_cbm_overlaps_pseudo_locked - Test if CBM or portion is pseudo-locked + * @d: RDT domain + * @_cbm: CBM to test + * + * @d represents a cache instance and @_cbm a capacity bitmask that is + * considered for it. Determine if @_cbm overlaps with any existing + * pseudo-locked region on @d. + * + * Return: true if @_cbm overlaps with pseudo-locked region on @d, false + * otherwise. + */ +bool rdtgroup_cbm_overlaps_pseudo_locked(struct rdt_domain *d, u32 _cbm) +{ + unsigned long *cbm = (unsigned long *)&_cbm; + unsigned long *cbm_b; + unsigned int cbm_len; + + if (d->plr) { + cbm_len = d->plr->r->cache.cbm_len; + cbm_b = (unsigned long *)&d->plr->cbm; + if (bitmap_intersects(cbm, cbm_b, cbm_len)) + return true; + } + + return false; +} + +/** + * rdtgroup_pseudo_locked_in_hierarchy - Pseudo-locked region in cache hierarchy + * @d: RDT domain under test + * + * The setup of a pseudo-locked region affects all cache instances within + * the hierarchy of the region. It is thus essential to know if any + * pseudo-locked regions exist within a cache hierarchy to prevent any + * attempts to create new pseudo-locked regions in the same hierarchy. + * + * Return: true if a pseudo-locked region exists in the hierarchy of @d or + * if it is not possible to test due to memory allocation issue, + * false otherwise. + */ +bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_domain *d) +{ + cpumask_var_t cpu_with_psl; + struct rdt_resource *r; + struct rdt_domain *d_i; + bool ret = false; + + if (!zalloc_cpumask_var(&cpu_with_psl, GFP_KERNEL)) + return true; + + /* + * First determine which cpus have pseudo-locked regions + * associated with them. + */ + for_each_alloc_enabled_rdt_resource(r) { + list_for_each_entry(d_i, &r->domains, list) { + if (d_i->plr) + cpumask_or(cpu_with_psl, cpu_with_psl, + &d_i->cpu_mask); + } + } + + /* + * Next test if new pseudo-locked region would intersect with + * existing region. + */ + if (cpumask_intersects(&d->cpu_mask, cpu_with_psl)) + ret = true; + + free_cpumask_var(cpu_with_psl); + return ret; +}