From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932603AbdJ0Co0 (ORCPT ); Thu, 26 Oct 2017 22:44:26 -0400 Received: from mail.kernel.org ([198.145.29.99]:37900 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751520AbdJ0CnJ (ORCPT ); Thu, 26 Oct 2017 22:43:09 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5EC652193C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=frederic@kernel.org From: Frederic Weisbecker To: Ingo Molnar Cc: LKML , Frederic Weisbecker , Peter Zijlstra , Linus Torvalds , Chris Metcalf , Thomas Gleixner , Luiz Capitulino , Christoph Lameter , "Paul E . McKenney" , Mike Galbraith , Rik van Riel , Wanpeng Li Subject: [PATCH 07/12] housekeeping: Move it under its own config, independent from NO_HZ Date: Fri, 27 Oct 2017 04:42:34 +0200 Message-Id: <1509072159-31808-8-git-send-email-frederic@kernel.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1509072159-31808-1-git-send-email-frederic@kernel.org> References: <1509072159-31808-1-git-send-email-frederic@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Split housekeeping config from CONFIG_NO_HZ_FULL. This way we finally separate the isolation code from nohz. Although a dependency to CONFIG_NO_HZ_FULL remains for now until the housekeeping code doesn't deal anymore with nohz internals directly. Signed-off-by: Frederic Weisbecker Cc: Chris Metcalf Cc: Christoph Lameter Cc: Linus Torvalds Cc: Luiz Capitulino Cc: Mike Galbraith Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Rik van Riel Cc: Thomas Gleixner Cc: Wanpeng Li --- include/linux/sched/isolation.h | 6 +++--- init/Kconfig | 8 ++++++++ kernel/sched/Makefile | 2 +- 3 files changed, 12 insertions(+), 4 deletions(-) diff --git a/include/linux/sched/isolation.h b/include/linux/sched/isolation.h index ad0f5d9..93ac2367 100644 --- a/include/linux/sched/isolation.h +++ b/include/linux/sched/isolation.h @@ -5,7 +5,7 @@ #include #include -#ifdef CONFIG_NO_HZ_FULL +#ifdef CONFIG_CPU_ISOLATION DECLARE_STATIC_KEY_FALSE(housekeeping_overriden); extern int housekeeping_any_cpu(void); extern const struct cpumask *housekeeping_cpumask(void); @@ -27,11 +27,11 @@ static inline const struct cpumask *housekeeping_cpumask(void) static inline void housekeeping_affine(struct task_struct *t) { } static inline void housekeeping_init(void) { } -#endif /* CONFIG_NO_HZ_FULL */ +#endif /* CONFIG_CPU_ISOLATION */ static inline bool housekeeping_cpu(int cpu) { -#ifdef CONFIG_NO_HZ_FULL +#ifdef CONFIG_CPU_ISOLATION if (static_branch_unlikely(&housekeeping_overriden)) return housekeeping_test_cpu(cpu); #endif diff --git a/init/Kconfig b/init/Kconfig index 78cb246..6f52e6f 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -472,6 +472,14 @@ config TASK_IO_ACCOUNTING endmenu # "CPU/Task time and stats accounting" +config CPU_ISOLATION + bool "CPU isolation" + depends on NO_HZ_FULL + help + Make sure that CPUs running critical tasks are not disturbed by + any source of "noise" such as unbound workqueues, timers, kthreads... + Unbound jobs get offloaded to housekeeping CPUs. + source "kernel/rcu/Kconfig" config BUILD_BIN2C diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile index 871d43d..dbe6130 100644 --- a/kernel/sched/Makefile +++ b/kernel/sched/Makefile @@ -26,4 +26,4 @@ obj-$(CONFIG_CGROUP_CPUACCT) += cpuacct.o obj-$(CONFIG_CPU_FREQ) += cpufreq.o obj-$(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) += cpufreq_schedutil.o obj-$(CONFIG_MEMBARRIER) += membarrier.o -obj-$(CONFIG_NO_HZ_FULL) += isolation.o +obj-$(CONFIG_CPU_ISOLATION) += isolation.o -- 2.7.4