From mboxrd@z Thu Jan 1 00:00:00 1970 From: Morten Rasmussen Subject: [RFCv5 PATCH 39/46] sched/cpufreq_sched: use static key for cpu frequency selection Date: Tue, 7 Jul 2015 19:24:22 +0100 Message-ID: <1436293469-25707-40-git-send-email-morten.rasmussen@arm.com> References: <1436293469-25707-1-git-send-email-morten.rasmussen@arm.com> Return-path: In-Reply-To: <1436293469-25707-1-git-send-email-morten.rasmussen@arm.com> Sender: linux-kernel-owner@vger.kernel.org To: peterz@infradead.org, mingo@redhat.com Cc: vincent.guittot@linaro.org, daniel.lezcano@linaro.org, Dietmar Eggemann , yuyang.du@intel.com, mturquette@baylibre.com, rjw@rjwysocki.net, Juri Lelli , sgurrappadi@nvidia.com, pang.xunlei@zte.com.cn, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, Juri Lelli List-Id: linux-pm@vger.kernel.org From: Juri Lelli Introduce a static key to only affect scheduler hot paths when sched governor is enabled. cc: Ingo Molnar cc: Peter Zijlstra Signed-off-by: Juri Lelli --- kernel/sched/cpufreq_sched.c | 14 ++++++++++++++ kernel/sched/fair.c | 1 + kernel/sched/sched.h | 6 ++++++ 3 files changed, 21 insertions(+) diff --git a/kernel/sched/cpufreq_sched.c b/kernel/sched/cpufreq_sched.c index 5020f24..2968f3a 100644 --- a/kernel/sched/cpufreq_sched.c +++ b/kernel/sched/cpufreq_sched.c @@ -203,6 +203,18 @@ void cpufreq_sched_set_cap(int cpu, unsigned long capacity) return; } +static inline void set_sched_energy_freq(void) +{ + if (!sched_energy_freq()) + static_key_slow_inc(&__sched_energy_freq); +} + +static inline void clear_sched_energy_freq(void) +{ + if (sched_energy_freq()) + static_key_slow_dec(&__sched_energy_freq); +} + static int cpufreq_sched_start(struct cpufreq_policy *policy) { struct gov_data *gd; @@ -243,6 +255,7 @@ static int cpufreq_sched_start(struct cpufreq_policy *policy) policy->governor_data = gd; gd->policy = policy; + set_sched_energy_freq(); return 0; err: @@ -254,6 +267,7 @@ static int cpufreq_sched_stop(struct cpufreq_policy *policy) { struct gov_data *gd = policy->governor_data; + clear_sched_energy_freq(); if (cpufreq_driver_might_sleep()) { kthread_stop(gd->task); } diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index f7cb6c9..d395bc9 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4282,6 +4282,7 @@ static inline void hrtick_update(struct rq *rq) #endif static bool cpu_overutilized(int cpu); +struct static_key __sched_energy_freq __read_mostly = STATIC_KEY_INIT_FALSE; /* * The enqueue_task method is called before nr_running is diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 30aa0c4..b5e27d9 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1476,6 +1476,12 @@ unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu) } #endif +extern struct static_key __sched_energy_freq; +static inline bool sched_energy_freq(void) +{ + return static_key_false(&__sched_energy_freq); +} + #ifdef CONFIG_CPU_FREQ_GOV_SCHED void cpufreq_sched_set_cap(int cpu, unsigned long util); #else -- 1.9.1