From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967301AbeE2VDr (ORCPT ); Tue, 29 May 2018 17:03:47 -0400 Received: from mga01.intel.com ([192.55.52.88]:53962 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966175AbeE2VBM (ORCPT ); Tue, 29 May 2018 17:01:12 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.49,457,1520924400"; d="scan'208";a="60127721" From: Reinette Chatre To: tglx@linutronix.de, fenghua.yu@intel.com, tony.luck@intel.com, vikas.shivappa@linux.intel.com Cc: gavin.hindman@intel.com, jithu.joseph@intel.com, dave.hansen@intel.com, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, linux-kernel@vger.kernel.org, Reinette Chatre Subject: [PATCH V5 18/38] x86/intel_rdt: Add utility to test if tasks assigned to resource group Date: Tue, 29 May 2018 05:57:43 -0700 Message-Id: <9149005d01de4b197bae13a45e6efdb536383ca1.1527593970.git.reinette.chatre@intel.com> X-Mailer: git-send-email 2.13.6 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In considering changes to a resource group it becomes necessary to know whether tasks have been assigned to the resource group in question. Introduce a new utility that can be used to check if any tasks have been assigned to a particular resource group. Signed-off-by: Reinette Chatre --- arch/x86/kernel/cpu/intel_rdt.h | 1 + arch/x86/kernel/cpu/intel_rdt_rdtgroup.c | 26 ++++++++++++++++++++++++++ 2 files changed, 27 insertions(+) diff --git a/arch/x86/kernel/cpu/intel_rdt.h b/arch/x86/kernel/cpu/intel_rdt.h index bda87f5ef7bc..10a1539cbec6 100644 --- a/arch/x86/kernel/cpu/intel_rdt.h +++ b/arch/x86/kernel/cpu/intel_rdt.h @@ -480,6 +480,7 @@ bool rdtgroup_cbm_overlaps(struct rdt_resource *r, struct rdt_domain *d, unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r, struct rdt_domain *d, u32 cbm); enum rdtgrp_mode rdtgroup_mode_by_closid(int closid); +int rdtgroup_tasks_assigned(struct rdtgroup *r); 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_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c index 83379982f26a..8f754a05d44d 100644 --- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c +++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c @@ -564,6 +564,32 @@ static int __rdtgroup_move_task(struct task_struct *tsk, return ret; } +/** + * rdtgroup_tasks_assigned - Test if tasks have been assigned to resource group + * @r: Resource group + * + * Return: 1 if tasks have been assigned to @r, 0 otherwise + */ +int rdtgroup_tasks_assigned(struct rdtgroup *r) +{ + struct task_struct *p, *t; + int ret = 0; + + lockdep_assert_held(&rdtgroup_mutex); + + rcu_read_lock(); + for_each_process_thread(p, t) { + if ((r->type == RDTCTRL_GROUP && t->closid == r->closid) || + (r->type == RDTMON_GROUP && t->rmid == r->mon.rmid)) { + ret = 1; + break; + } + } + rcu_read_unlock(); + + return ret; +} + static int rdtgroup_task_write_permission(struct task_struct *task, struct kernfs_open_file *of) { -- 2.13.6