From dfc616d8b3df3013c579e023e67f29ada60bdd50 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Wed, 24 Aug 2016 11:14:44 +0200 Subject: [PATCH] cpuidle/coupled: Convert to hotplug state machine Install the callbacks via the state machine. Signed-off-by: Sebastian Andrzej Siewior Cc: linux-pm@vger.kernel.org Cc: Peter Zijlstra Cc: Daniel Lezcano Cc: "Rafael J. Wysocki" Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160824091444.brdr5zpbxjvh6n3f@linutronix.de Signed-off-by: Thomas Gleixner --- drivers/cpuidle/coupled.c | 75 ++++++++++++++++---------------------- include/linux/cpuhotplug.h | 1 + 2 files changed, 32 insertions(+), 44 deletions(-) diff --git a/drivers/cpuidle/coupled.c b/drivers/cpuidle/coupled.c index d5657d50ac40..71e586d7df71 100644 --- a/drivers/cpuidle/coupled.c +++ b/drivers/cpuidle/coupled.c @@ -749,65 +749,52 @@ static void cpuidle_coupled_allow_idle(struct cpuidle_coupled *coupled) put_cpu(); } -/** - * cpuidle_coupled_cpu_notify - notifier called during hotplug transitions - * @nb: notifier block - * @action: hotplug transition - * @hcpu: target cpu number - * - * Called when a cpu is brought on or offline using hotplug. Updates the - * coupled cpu set appropriately - */ -static int cpuidle_coupled_cpu_notify(struct notifier_block *nb, - unsigned long action, void *hcpu) +static int coupled_cpu_online(unsigned int cpu) { - int cpu = (unsigned long)hcpu; struct cpuidle_device *dev; - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_UP_PREPARE: - case CPU_DOWN_PREPARE: - case CPU_ONLINE: - case CPU_DEAD: - case CPU_UP_CANCELED: - case CPU_DOWN_FAILED: - break; - default: - return NOTIFY_OK; - } - mutex_lock(&cpuidle_lock); dev = per_cpu(cpuidle_devices, cpu); - if (!dev || !dev->coupled) - goto out; - - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_UP_PREPARE: - case CPU_DOWN_PREPARE: - cpuidle_coupled_prevent_idle(dev->coupled); - break; - case CPU_ONLINE: - case CPU_DEAD: + if (dev && dev->coupled) { cpuidle_coupled_update_online_cpus(dev->coupled); - /* Fall through */ - case CPU_UP_CANCELED: - case CPU_DOWN_FAILED: cpuidle_coupled_allow_idle(dev->coupled); - break; } -out: mutex_unlock(&cpuidle_lock); - return NOTIFY_OK; + return 0; } -static struct notifier_block cpuidle_coupled_cpu_notifier = { - .notifier_call = cpuidle_coupled_cpu_notify, -}; +static int coupled_cpu_up_prepare(unsigned int cpu) +{ + struct cpuidle_device *dev; + + mutex_lock(&cpuidle_lock); + + dev = per_cpu(cpuidle_devices, cpu); + if (dev && dev->coupled) + cpuidle_coupled_prevent_idle(dev->coupled); + + mutex_unlock(&cpuidle_lock); + return 0; +} static int __init cpuidle_coupled_init(void) { - return register_cpu_notifier(&cpuidle_coupled_cpu_notifier); + int ret; + + ret = cpuhp_setup_state_nocalls(CPUHP_CPUIDLE_COUPLED_PREPARE, + "cpuidle/coupled:prepare", + coupled_cpu_up_prepare, + coupled_cpu_online); + if (ret) + return ret; + ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, + "cpuidle/coupled:online", + coupled_cpu_online, + coupled_cpu_up_prepare); + if (ret < 0) + cpuhp_remove_state_nocalls(CPUHP_CPUIDLE_COUPLED_PREPARE); + return ret; } core_initcall(cpuidle_coupled_init); diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 0fb22b95649f..e8608774b5da 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -30,6 +30,7 @@ enum cpuhp_state { CPUHP_SLAB_PREPARE, CPUHP_MD_RAID5_PREPARE, CPUHP_RCUTREE_PREP, + CPUHP_CPUIDLE_COUPLED_PREPARE, CPUHP_NOTIFY_PREPARE, CPUHP_TIMERS_DEAD, CPUHP_BRINGUP_CPU,