From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754820Ab2I0JFJ (ORCPT ); Thu, 27 Sep 2012 05:05:09 -0400 Received: from service87.mimecast.com ([91.220.42.44]:49452 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752090Ab2I0JEl (ORCPT ); Thu, 27 Sep 2012 05:04:41 -0400 From: Viresh Kumar To: linux-kernel@vger.kernel.org Cc: pjt@google.com, paul.mckenney@linaro.org, tglx@linutronix.de, tj@kernel.org, suresh.b.siddha@intel.com, venki@google.com, mingo@redhat.com, peterz@infradead.org, robin.randhawa@arm.com, Steve.Bannister@arm.com, Arvind.Chauhan@arm.com, amit.kucheria@linaro.org, vincent.guittot@linaro.org, linaro-dev@lists.linaro.org, patches@linaro.org, Viresh Kumar Subject: [PATCH V2 2/3] timer: hrtimer: Don't check idle_cpu() before calling get_nohz_timer_target() Date: Thu, 27 Sep 2012 14:34:04 +0530 Message-Id: <169feed8cddec1edecb311d2471df0a553d6e865.1348736069.git.viresh.kumar@linaro.org> X-Mailer: git-send-email 1.7.12.rc2.18.g61b472e In-Reply-To: References: In-Reply-To: References: X-OriginalArrivalTime: 27 Sep 2012 09:04:16.0943 (UTC) FILETIME=[12920BF0:01CD9C8F] X-MC-Unique: 112092710043920701 Content-Type: text/plain; charset=WINDOWS-1252 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id q8R95C1t004064 Check for current cpu's idleness already done in implementation of sched_select_cpu() which is called by get_nohz_timer_target(). So, no need to call idle_cpu() twice, once from sched_select_cpu() and once from timer and hrtimer before calling get_nohz_timer_target(). This patch removes calls to idle_cpu() from timer and hrtimer. Signed-off-by: Viresh Kumar --- kernel/hrtimer.c | 2 +- kernel/timer.c | 9 +++++---- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 6db7a5e..74bdaf6 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -159,7 +159,7 @@ struct hrtimer_clock_base *lock_hrtimer_base(const struct hrtimer *timer, static int hrtimer_get_target(int this_cpu, int pinned) { #ifdef CONFIG_NO_HZ - if (!pinned && get_sysctl_timer_migration() && idle_cpu(this_cpu)) + if (!pinned && get_sysctl_timer_migration()) return get_nohz_timer_target(); #endif return this_cpu; diff --git a/kernel/timer.c b/kernel/timer.c index d5de1b2..8409d9d 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -720,7 +720,7 @@ __mod_timer(struct timer_list *timer, unsigned long expires, { struct tvec_base *base, *new_base; unsigned long flags; - int ret = 0 , cpu; + int ret = 0 , cpu = 0; timer_stats_timer_set_start_info(timer); BUG_ON(!timer->function); @@ -733,12 +733,13 @@ __mod_timer(struct timer_list *timer, unsigned long expires, debug_activate(timer, expires); - cpu = smp_processor_id(); - #if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP) - if (!pinned && get_sysctl_timer_migration() && idle_cpu(cpu)) + if (!pinned && get_sysctl_timer_migration()) cpu = get_nohz_timer_target(); #endif + if (!cpu) + cpu = smp_processor_id(); + new_base = per_cpu(tvec_bases, cpu); if (base != new_base) { -- 1.7.12.rc2.18.g61b472e