From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753935Ab3LCMg0 (ORCPT ); Tue, 3 Dec 2013 07:36:26 -0500 Received: from mail-pb0-f42.google.com ([209.85.160.42]:54025 "EHLO mail-pb0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752870Ab3LCMgX (ORCPT ); Tue, 3 Dec 2013 07:36:23 -0500 From: Alex Shi To: mingo@redhat.com, peterz@infradead.org, morten.rasmussen@arm.com, vincent.guittot@linaro.org, daniel.lezcano@linaro.org, fweisbec@gmail.com, linux@arm.linux.org.uk, tony.luck@intel.com, fenghua.yu@intel.com, tglx@linutronix.de, akpm@linux-foundation.org, arjan@linux.intel.com, pjt@google.com, fengguang.wu@intel.com Cc: james.hogan@imgtec.com, alex.shi@linaro.org, jason.low2@hp.com, viresh.kumar@linaro.org, hanjun.guo@linaro.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 3/3] nohz_full: update cpu load fix in nohz_full Date: Tue, 3 Dec 2013 20:35:12 +0800 Message-Id: <1386074112-30754-4-git-send-email-alex.shi@linaro.org> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1386074112-30754-1-git-send-email-alex.shi@linaro.org> References: <1386074112-30754-1-git-send-email-alex.shi@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We are not always 0 when update nohz cpu load, after nohz_full enabled. But current code still treat the cpu as idle. that is incorrect. Fix it to use correct cpu_load. Signed-off-by: Alex Shi --- kernel/sched/proc.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/kernel/sched/proc.c b/kernel/sched/proc.c index 16f5a30..f1441f0 100644 --- a/kernel/sched/proc.c +++ b/kernel/sched/proc.c @@ -568,8 +568,14 @@ void update_cpu_load_nohz(void) /* * We were idle, this means load 0, the current load might be * !0 due to remote wakeups and the sort. + * or we may has only one task and in NO_HZ_FULL, then still use + * normal cpu load. */ - __update_cpu_load(this_rq, 0, pending_updates); + if (this_rq->cfs.h_nr_running) { + unsigned load = get_rq_runnable_load(this_rq); + __update_cpu_load(this_rq, load, pending_updates); + } else + __update_cpu_load(this_rq, 0, pending_updates); } raw_spin_unlock(&this_rq->lock); } -- 1.8.1.2