From nobody Sat Feb 7 08:33:45 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AC028EEAA59 for ; Thu, 14 Sep 2023 17:24:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240190AbjINRYN (ORCPT ); Thu, 14 Sep 2023 13:24:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38658 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239636AbjINRXu (ORCPT ); Thu, 14 Sep 2023 13:23:50 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 7506A30F7 for ; Thu, 14 Sep 2023 10:23:03 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7106811FB; Thu, 14 Sep 2023 10:23:40 -0700 (PDT) Received: from merodach.members.linode.com (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6C9B73F5A1; Thu, 14 Sep 2023 10:23:00 -0700 (PDT) From: James Morse To: x86@kernel.org, linux-kernel@vger.kernel.org Cc: Fenghua Yu , Reinette Chatre , Thomas Gleixner , Ingo Molnar , Borislav Petkov , H Peter Anvin , Babu Moger , James Morse , shameerali.kolothum.thodi@huawei.com, D Scott Phillips OS , carl@os.amperecomputing.com, lcherian@marvell.com, bobo.shaobowang@huawei.com, tan.shaopeng@fujitsu.com, xingxin.hx@openanolis.org, baolin.wang@linux.alibaba.com, Jamie Iles , Xin Hao , peternewman@google.com, dfustini@baylibre.com, amitsinght@marvell.com Subject: [PATCH v6 22/24] x86/resctrl: Add cpu offline callback for resctrl work Date: Thu, 14 Sep 2023 17:21:36 +0000 Message-Id: <20230914172138.11977-23-james.morse@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20230914172138.11977-1-james.morse@arm.com> References: <20230914172138.11977-1-james.morse@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" The resctrl architecture specific code may need to free a domain when a CPU goes offline, it also needs to reset the CPUs PQR_ASSOC register. Amongst other things, the resctrl filesystem code needs to clear this CPU from the cpu_mask of any control and monitor groups. Currently this is all done in core.c and called from resctrl_offline_cpu(), making the split between architecture and filesystem code unclear. Move the filesystem work to remove the CPU from the control and monitor groups into a filesystem helper called resctrl_offline_cpu(), and rename the one in core.c resctrl_arch_offline_cpu(). The rdtgroup_mutex is unlocked and locked again in the call in preparation for changing the locking rules for the architecture code. Reviewed-by: Shaopeng Tan Tested-by: Shaopeng Tan Tested-By: Peter Newman Signed-off-by: James Morse Reviewed-by: Reinette Chatre --- arch/x86/kernel/cpu/resctrl/core.c | 25 +++++-------------------- arch/x86/kernel/cpu/resctrl/rdtgroup.c | 24 ++++++++++++++++++++++++ include/linux/resctrl.h | 1 + 3 files changed, 30 insertions(+), 20 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resct= rl/core.c index 37aa124f1e4c..00b1592fd059 100644 --- a/arch/x86/kernel/cpu/resctrl/core.c +++ b/arch/x86/kernel/cpu/resctrl/core.c @@ -623,31 +623,15 @@ static int resctrl_arch_online_cpu(unsigned int cpu) return 0; } =20 -static void clear_childcpus(struct rdtgroup *r, unsigned int cpu) +static int resctrl_arch_offline_cpu(unsigned int cpu) { - struct rdtgroup *cr; - - list_for_each_entry(cr, &r->mon.crdtgrp_list, mon.crdtgrp_list) { - if (cpumask_test_and_clear_cpu(cpu, &cr->cpu_mask)) { - break; - } - } -} - -static int resctrl_offline_cpu(unsigned int cpu) -{ - struct rdtgroup *rdtgrp; struct rdt_resource *r; =20 mutex_lock(&rdtgroup_mutex); + resctrl_offline_cpu(cpu); + for_each_capable_rdt_resource(r) domain_remove_cpu(cpu, r); - list_for_each_entry(rdtgrp, &rdt_all_groups, rdtgroup_list) { - if (cpumask_test_and_clear_cpu(cpu, &rdtgrp->cpu_mask)) { - clear_childcpus(rdtgrp, cpu); - break; - } - } clear_closid_rmid(cpu); mutex_unlock(&rdtgroup_mutex); =20 @@ -970,7 +954,8 @@ static int __init resctrl_late_init(void) =20 state =3D cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/resctrl/cat:online:", - resctrl_arch_online_cpu, resctrl_offline_cpu); + resctrl_arch_online_cpu, + resctrl_arch_offline_cpu); if (state < 0) return state; =20 diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/r= esctrl/rdtgroup.c index 49f100c73838..f06a80d8fa3b 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -3878,6 +3878,30 @@ void resctrl_online_cpu(unsigned int cpu) cpumask_set_cpu(cpu, &rdtgroup_default.cpu_mask); } =20 +static void clear_childcpus(struct rdtgroup *r, unsigned int cpu) +{ + struct rdtgroup *cr; + + list_for_each_entry(cr, &r->mon.crdtgrp_list, mon.crdtgrp_list) { + if (cpumask_test_and_clear_cpu(cpu, &cr->cpu_mask)) + break; + } +} + +void resctrl_offline_cpu(unsigned int cpu) +{ + struct rdtgroup *rdtgrp; + + lockdep_assert_held(&rdtgroup_mutex); + + list_for_each_entry(rdtgrp, &rdt_all_groups, rdtgroup_list) { + if (cpumask_test_and_clear_cpu(cpu, &rdtgrp->cpu_mask)) { + clear_childcpus(rdtgrp, cpu); + break; + } + } +} + /* * rdtgroup_init - rdtgroup initialization * diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h index 0888d1975161..74886cda5f66 100644 --- a/include/linux/resctrl.h +++ b/include/linux/resctrl.h @@ -226,6 +226,7 @@ u32 resctrl_arch_get_config(struct rdt_resource *r, str= uct rdt_domain *d, int resctrl_online_domain(struct rdt_resource *r, struct rdt_domain *d); void resctrl_offline_domain(struct rdt_resource *r, struct rdt_domain *d); void resctrl_online_cpu(unsigned int cpu); +void resctrl_offline_cpu(unsigned int cpu); =20 /** * resctrl_arch_rmid_read() - Read the eventid counter corresponding to rm= id --=20 2.39.2