From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752880AbcAMQBp (ORCPT ); Wed, 13 Jan 2016 11:01:45 -0500 Received: from mail-wm0-f66.google.com ([74.125.82.66]:36561 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752335AbcAMQBl (ORCPT ); Wed, 13 Jan 2016 11:01:41 -0500 From: Frederic Weisbecker To: Peter Zijlstra Cc: LKML , Frederic Weisbecker , Byungchul Park , Chris Metcalf , Thomas Gleixner , Luiz Capitulino , Christoph Lameter , "Paul E . McKenney" , Mike Galbraith , Rik van Riel Subject: [PATCH 2/4] sched: Consolidate nohz CPU load update code Date: Wed, 13 Jan 2016 17:01:29 +0100 Message-Id: <1452700891-21807-3-git-send-email-fweisbec@gmail.com> X-Mailer: git-send-email 2.6.4 In-Reply-To: <1452700891-21807-1-git-send-email-fweisbec@gmail.com> References: <1452700891-21807-1-git-send-email-fweisbec@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Lets factorize a bit of code there. We'll even have a third user soon. While at it, standardize the idle update function name against the others. Cc: Byungchul Park Cc: Mike Galbraith Cc: Chris Metcalf Cc: Christoph Lameter Cc: Luiz Capitulino Cc: Paul E . McKenney Cc: Rik van Riel Cc: Thomas Gleixner Signed-off-by: Frederic Weisbecker --- kernel/sched/fair.c | 48 +++++++++++++++++++++++++----------------------- 1 file changed, 25 insertions(+), 23 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index b849ea8..161cee2 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4450,6 +4450,25 @@ static unsigned long weighted_cpuload(const int cpu) } #ifdef CONFIG_NO_HZ_COMMON +static void __update_cpu_load_nohz(struct rq *this_rq, + unsigned long curr_jiffies, + unsigned long load, + int active) +{ + unsigned long pending_updates; + + pending_updates = curr_jiffies - this_rq->last_load_update_tick; + if (pending_updates) { + this_rq->last_load_update_tick = curr_jiffies; + /* + * In the regular NOHZ case, we were idle, this means load 0. + * In the NOHZ_FULL case, we were non-idle, we should consider + * its weighted load. + */ + __update_cpu_load(this_rq, load, pending_updates, active); + } +} + /* * There is no sane way to deal with nohz on smp when using jiffies because the * cpu doing the jiffies update might drift wrt the cpu doing the jiffy reading @@ -4467,22 +4486,15 @@ static unsigned long weighted_cpuload(const int cpu) * Called from nohz_idle_balance() to update the load ratings before doing the * idle balance. */ -static void update_idle_cpu_load(struct rq *this_rq) +static void update_cpu_load_idle(struct rq *this_rq) { - unsigned long curr_jiffies = READ_ONCE(jiffies); - unsigned long load = weighted_cpuload(cpu_of(this_rq)); - unsigned long pending_updates; - /* * bail if there's load or we're actually up-to-date. */ - if (load || curr_jiffies == this_rq->last_load_update_tick) + if (weighted_cpuload(cpu_of(this_rq))) return; - pending_updates = curr_jiffies - this_rq->last_load_update_tick; - this_rq->last_load_update_tick = curr_jiffies; - - __update_cpu_load(this_rq, load, pending_updates, 0); + __update_cpu_load_nohz(this_rq, READ_ONCE(jiffies), 0, 0); } /* @@ -4493,22 +4505,12 @@ void update_cpu_load_nohz(int active) struct rq *this_rq = this_rq(); unsigned long curr_jiffies = READ_ONCE(jiffies); unsigned long load = active ? weighted_cpuload(cpu_of(this_rq)) : 0; - unsigned long pending_updates; if (curr_jiffies == this_rq->last_load_update_tick) return; raw_spin_lock(&this_rq->lock); - pending_updates = curr_jiffies - this_rq->last_load_update_tick; - if (pending_updates) { - this_rq->last_load_update_tick = curr_jiffies; - /* - * In the regular NOHZ case, we were idle, this means load 0. - * In the NOHZ_FULL case, we were non-idle, we should consider - * its weighted load. - */ - __update_cpu_load(this_rq, load, pending_updates, active); - } + __update_cpu_load_nohz(this_rq, curr_jiffies, load, active); raw_spin_unlock(&this_rq->lock); } #endif /* CONFIG_NO_HZ */ @@ -4529,7 +4531,7 @@ void update_cpu_load_active(struct rq *this_rq) if (tick_nohz_tick_stopped()) return; /* - * See the mess around update_idle_cpu_load() / update_cpu_load_nohz(). + * See the mess around update_cpu_load_idle() / update_cpu_load_nohz(). */ load = weighted_cpuload(cpu_of(this_rq)); this_rq->last_load_update_tick = jiffies; @@ -7824,7 +7826,7 @@ static void nohz_idle_balance(struct rq *this_rq, enum cpu_idle_type idle) if (time_after_eq(jiffies, rq->next_balance)) { raw_spin_lock_irq(&rq->lock); update_rq_clock(rq); - update_idle_cpu_load(rq); + update_cpu_load_idle(rq); raw_spin_unlock_irq(&rq->lock); rebalance_domains(rq, CPU_IDLE); } -- 2.6.4