From patchwork Wed Dec 2 09:57:05 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arun Bharadwaj X-Patchwork-Id: 39972 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from bilbo.ozlabs.org (localhost [127.0.0.1]) by ozlabs.org (Postfix) with ESMTP id D36BFB7FE2 for ; Wed, 2 Dec 2009 20:57:19 +1100 (EST) Received: from e28smtp06.in.ibm.com (e28smtp06.in.ibm.com [122.248.162.6]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e28smtp06.in.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 056E5B7BDC for ; Wed, 2 Dec 2009 20:57:10 +1100 (EST) Received: from d28relay01.in.ibm.com (d28relay01.in.ibm.com [9.184.220.58]) by e28smtp06.in.ibm.com (8.14.3/8.13.1) with ESMTP id nB29v82u003303 for ; Wed, 2 Dec 2009 15:27:08 +0530 Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay01.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id nB29v8Wo1290362 for ; Wed, 2 Dec 2009 15:27:08 +0530 Received: from d28av04.in.ibm.com (loopback [127.0.0.1]) by d28av04.in.ibm.com (8.14.3/8.13.1/NCO v10.0 AVout) with ESMTP id nB29v7au025602 for ; Wed, 2 Dec 2009 20:57:07 +1100 Received: from linux.vnet.ibm.com (Crystal-Planet.in.ibm.com [9.124.35.99]) by d28av04.in.ibm.com (8.14.3/8.13.1/NCO v10.0 AVin) with ESMTP id nB29v5qC025547 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Wed, 2 Dec 2009 20:57:06 +1100 Date: Wed, 2 Dec 2009 15:27:05 +0530 From: Arun R Bharadwaj To: Peter Zijlstra , Benjamin Herrenschmidt , Ingo Molnar , Vaidyanathan Srinivasan , Dipankar Sarma , Balbir Singh , Venkatesh Pallipadi , Arun Bharadwaj Subject: [v10 PATCH 2/9]: cpuidle: cleanup drivers/cpuidle/cpuidle.c Message-ID: <20091202095705.GC27251@linux.vnet.ibm.com> References: <20091202095427.GA27251@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20091202095427.GA27251@linux.vnet.ibm.com> User-Agent: Mutt/1.5.20 (2009-06-14) Cc: linux-arch@vger.kernel.org, linux-acpi@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.12 Precedence: list Reply-To: arun@linux.vnet.ibm.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org * Arun R Bharadwaj [2009-12-02 15:24:27]: This patch cleans up drivers/cpuidle/cpuidle.c Earlier cpuidle assumed pm_idle as the default idle loop. Break that assumption and make it more generic. cpuidle_idle_call() which is the main idle loop of cpuidle is to be called by architectures which have registered to cpuidle. Signed-off-by: Arun R Bharadwaj --- drivers/cpuidle/cpuidle.c | 93 +++++++++++---------------------------------- drivers/cpuidle/cpuidle.h | 6 -- drivers/cpuidle/driver.c | 4 - drivers/cpuidle/governor.c | 13 ++---- drivers/cpuidle/sysfs.c | 34 +++++++++------- include/linux/cpuidle.h | 10 +++- 6 files changed, 58 insertions(+), 102 deletions(-) Index: linux.trees.git/drivers/cpuidle/cpuidle.c =================================================================== --- linux.trees.git.orig/drivers/cpuidle/cpuidle.c +++ linux.trees.git/drivers/cpuidle/cpuidle.c @@ -24,10 +24,6 @@ DEFINE_PER_CPU(struct cpuidle_device *, cpuidle_devices); DEFINE_MUTEX(cpuidle_lock); -LIST_HEAD(cpuidle_detected_devices); -static void (*pm_idle_old)(void); - -static int enabled_devices; #if defined(CONFIG_ARCH_HAS_CPU_IDLE_WAIT) static void cpuidle_kick_cpus(void) @@ -47,21 +43,20 @@ static int __cpuidle_register_device(str * * NOTE: no locks or semaphores should be used here */ -static void cpuidle_idle_call(void) +void cpuidle_idle_call(void) { struct cpuidle_device *dev = __get_cpu_var(cpuidle_devices); struct cpuidle_state *target_state; int next_state; + ktime_t t1, t2; + s64 diff; /* check if the device is ready */ if (!dev || !dev->enabled) { - if (pm_idle_old) - pm_idle_old(); - else #if defined(CONFIG_ARCH_HAS_DEFAULT_IDLE) - default_idle(); + default_idle(); #else - local_irq_enable(); + local_irq_enable(); #endif return; } @@ -75,7 +70,11 @@ static void cpuidle_idle_call(void) hrtimer_peek_ahead_timers(); #endif /* ask the governor for the next state */ - next_state = cpuidle_curr_governor->select(dev); + if (dev->state_count > 1) + next_state = cpuidle_curr_governor->select(dev); + else + next_state = 0; + if (need_resched()) { local_irq_enable(); return; @@ -85,7 +84,18 @@ static void cpuidle_idle_call(void) /* enter the state and update stats */ dev->last_state = target_state; - dev->last_residency = target_state->enter(dev, target_state); + + t1 = ktime_get(); + + target_state->enter(dev, target_state); + + t2 = ktime_get(); + diff = ktime_to_us(ktime_sub(t2, t1)); + if (diff > INT_MAX) + diff = INT_MAX; + + dev->last_residency = (int) diff; + if (dev->last_state) target_state = dev->last_state; @@ -99,35 +109,12 @@ static void cpuidle_idle_call(void) } /** - * cpuidle_install_idle_handler - installs the cpuidle idle loop handler - */ -void cpuidle_install_idle_handler(void) -{ - if (enabled_devices && (pm_idle != cpuidle_idle_call)) { - /* Make sure all changes finished before we switch to new idle */ - smp_wmb(); - pm_idle = cpuidle_idle_call; - } -} - -/** - * cpuidle_uninstall_idle_handler - uninstalls the cpuidle idle loop handler - */ -void cpuidle_uninstall_idle_handler(void) -{ - if (enabled_devices && pm_idle_old && (pm_idle != pm_idle_old)) { - pm_idle = pm_idle_old; - cpuidle_kick_cpus(); - } -} - -/** * cpuidle_pause_and_lock - temporarily disables CPUIDLE */ void cpuidle_pause_and_lock(void) { mutex_lock(&cpuidle_lock); - cpuidle_uninstall_idle_handler(); + cpuidle_kick_cpus(); } EXPORT_SYMBOL_GPL(cpuidle_pause_and_lock); @@ -137,7 +124,6 @@ EXPORT_SYMBOL_GPL(cpuidle_pause_and_lock */ void cpuidle_resume_and_unlock(void) { - cpuidle_install_idle_handler(); mutex_unlock(&cpuidle_lock); } @@ -185,7 +171,6 @@ int cpuidle_enable_device(struct cpuidle dev->enabled = 1; - enabled_devices++; return 0; fail_sysfs: @@ -216,30 +201,16 @@ void cpuidle_disable_device(struct cpuid cpuidle_curr_governor->disable(dev); cpuidle_remove_state_sysfs(dev); - enabled_devices--; } EXPORT_SYMBOL_GPL(cpuidle_disable_device); #ifdef CONFIG_ARCH_HAS_CPU_RELAX -static int poll_idle(struct cpuidle_device *dev, struct cpuidle_state *st) +static void poll_idle(struct cpuidle_device *dev, struct cpuidle_state *st) { - ktime_t t1, t2; - s64 diff; - int ret; - - t1 = ktime_get(); local_irq_enable(); while (!need_resched()) cpu_relax(); - - t2 = ktime_get(); - diff = ktime_to_us(ktime_sub(t2, t1)); - if (diff > INT_MAX) - diff = INT_MAX; - - ret = (int) diff; - return ret; } static void poll_idle_init(struct cpuidle_device *dev) @@ -269,7 +240,6 @@ static void poll_idle_init(struct cpuidl */ static int __cpuidle_register_device(struct cpuidle_device *dev) { - int ret; struct sys_device *sys_dev = get_cpu_sysdev((unsigned long)dev->cpu); if (!sys_dev) @@ -277,16 +247,9 @@ static int __cpuidle_register_device(str if (!try_module_get(cpuidle_curr_driver->owner)) return -EINVAL; - init_completion(&dev->kobj_unregister); - poll_idle_init(dev); per_cpu(cpuidle_devices, dev->cpu) = dev; - list_add(&dev->device_list, &cpuidle_detected_devices); - if ((ret = cpuidle_add_sysfs(sys_dev))) { - module_put(cpuidle_curr_driver->owner); - return ret; - } dev->registered = 1; return 0; @@ -308,7 +271,6 @@ int cpuidle_register_device(struct cpuid } cpuidle_enable_device(dev); - cpuidle_install_idle_handler(); mutex_unlock(&cpuidle_lock); @@ -324,8 +286,6 @@ EXPORT_SYMBOL_GPL(cpuidle_register_devic */ void cpuidle_unregister_device(struct cpuidle_device *dev) { - struct sys_device *sys_dev = get_cpu_sysdev((unsigned long)dev->cpu); - if (dev->registered == 0) return; @@ -333,9 +293,6 @@ void cpuidle_unregister_device(struct cp cpuidle_disable_device(dev); - cpuidle_remove_sysfs(sys_dev); - list_del(&dev->device_list); - wait_for_completion(&dev->kobj_unregister); per_cpu(cpuidle_devices, dev->cpu) = NULL; cpuidle_resume_and_unlock(); @@ -387,8 +344,6 @@ static int __init cpuidle_init(void) { int ret; - pm_idle_old = pm_idle; - ret = cpuidle_add_class_sysfs(&cpu_sysdev_class); if (ret) return ret; Index: linux.trees.git/drivers/cpuidle/governor.c =================================================================== --- linux.trees.git.orig/drivers/cpuidle/governor.c +++ linux.trees.git/drivers/cpuidle/governor.c @@ -43,16 +43,14 @@ static struct cpuidle_governor * __cpuid */ int cpuidle_switch_governor(struct cpuidle_governor *gov) { - struct cpuidle_device *dev; + int cpu; if (gov == cpuidle_curr_governor) return 0; - cpuidle_uninstall_idle_handler(); - if (cpuidle_curr_governor) { - list_for_each_entry(dev, &cpuidle_detected_devices, device_list) - cpuidle_disable_device(dev); + for_each_online_cpu(cpu) + cpuidle_disable_device(per_cpu(cpuidle_devices, cpu)); module_put(cpuidle_curr_governor->owner); } @@ -61,9 +59,8 @@ int cpuidle_switch_governor(struct cpuid if (gov) { if (!try_module_get(cpuidle_curr_governor->owner)) return -EINVAL; - list_for_each_entry(dev, &cpuidle_detected_devices, device_list) - cpuidle_enable_device(dev); - cpuidle_install_idle_handler(); + for_each_online_cpu(cpu) + cpuidle_enable_device(per_cpu(cpuidle_devices, cpu)); printk(KERN_INFO "cpuidle: using governor %s\n", gov->name); } Index: linux.trees.git/include/linux/cpuidle.h =================================================================== --- linux.trees.git.orig/include/linux/cpuidle.h +++ linux.trees.git/include/linux/cpuidle.h @@ -41,7 +41,7 @@ struct cpuidle_state { unsigned long long usage; unsigned long long time; /* in US */ - int (*enter) (struct cpuidle_device *dev, + void (*enter) (struct cpuidle_device *dev, struct cpuidle_state *state); }; @@ -92,7 +92,6 @@ struct cpuidle_device { struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX]; struct cpuidle_state *last_state; - struct list_head device_list; struct kobject kobj; struct completion kobj_unregister; void *governor_data; @@ -112,6 +111,9 @@ static inline int cpuidle_get_last_resid return dev->last_residency; } +extern struct cpuidle_driver *cpuidle_curr_driver; +extern void cpuidle_idle_call(void); + /**************************** * CPUIDLE DRIVER INTERFACE * @@ -133,6 +135,8 @@ extern void cpuidle_pause_and_lock(void) extern void cpuidle_resume_and_unlock(void); extern int cpuidle_enable_device(struct cpuidle_device *dev); extern void cpuidle_disable_device(struct cpuidle_device *dev); +extern int common_idle_loop(struct cpuidle_device *dev, + struct cpuidle_state *st, void (*idle)(void)); #else @@ -148,6 +152,8 @@ static inline void cpuidle_resume_and_un static inline int cpuidle_enable_device(struct cpuidle_device *dev) {return 0;} static inline void cpuidle_disable_device(struct cpuidle_device *dev) { } +static inline int common_idle_loop(struct cpuidle_device *dev, + struct cpuidle_state *st, void (*idle)(void)) { } #endif Index: linux.trees.git/drivers/cpuidle/cpuidle.h =================================================================== --- linux.trees.git.orig/drivers/cpuidle/cpuidle.h +++ linux.trees.git/drivers/cpuidle/cpuidle.h @@ -9,9 +9,7 @@ /* For internal use only */ extern struct cpuidle_governor *cpuidle_curr_governor; -extern struct cpuidle_driver *cpuidle_curr_driver; extern struct list_head cpuidle_governors; -extern struct list_head cpuidle_detected_devices; extern struct mutex cpuidle_lock; extern spinlock_t cpuidle_driver_lock; @@ -27,7 +25,7 @@ extern int cpuidle_add_class_sysfs(struc extern void cpuidle_remove_class_sysfs(struct sysdev_class *cls); extern int cpuidle_add_state_sysfs(struct cpuidle_device *device); extern void cpuidle_remove_state_sysfs(struct cpuidle_device *device); -extern int cpuidle_add_sysfs(struct sys_device *sysdev); -extern void cpuidle_remove_sysfs(struct sys_device *sysdev); +extern int cpuidle_add_sysfs(struct cpuidle_device *device); +extern void cpuidle_remove_sysfs(struct cpuidle_device *device); #endif /* __DRIVER_CPUIDLE_H */ Index: linux.trees.git/drivers/cpuidle/sysfs.c =================================================================== --- linux.trees.git.orig/drivers/cpuidle/sysfs.c +++ linux.trees.git/drivers/cpuidle/sysfs.c @@ -311,6 +311,13 @@ int cpuidle_add_state_sysfs(struct cpuid int i, ret = -ENOMEM; struct cpuidle_state_kobj *kobj; + init_completion(&device->kobj_unregister); + + ret = cpuidle_add_sysfs(device); + if (ret) { + module_put(cpuidle_curr_driver->owner); + return ret; + } /* state statistics */ for (i = 0; i < device->state_count; i++) { kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL); @@ -347,35 +354,32 @@ void cpuidle_remove_state_sysfs(struct c for (i = 0; i < device->state_count; i++) cpuidle_free_state_kobj(device, i); + + cpuidle_remove_sysfs(device); } /** * cpuidle_add_sysfs - creates a sysfs instance for the target device - * @sysdev: the target device + * @device: the target device */ -int cpuidle_add_sysfs(struct sys_device *sysdev) +int cpuidle_add_sysfs(struct cpuidle_device *device) { - int cpu = sysdev->id; - struct cpuidle_device *dev; int error; + struct sys_device *sysdev = get_cpu_sysdev((unsigned long)device->cpu); - dev = per_cpu(cpuidle_devices, cpu); - error = kobject_init_and_add(&dev->kobj, &ktype_cpuidle, &sysdev->kobj, - "cpuidle"); + error = kobject_init_and_add(&device->kobj, &ktype_cpuidle, + &sysdev->kobj, "cpuidle"); if (!error) - kobject_uevent(&dev->kobj, KOBJ_ADD); + kobject_uevent(&device->kobj, KOBJ_ADD); return error; } /** * cpuidle_remove_sysfs - deletes a sysfs instance on the target device - * @sysdev: the target device + * @device: the target device */ -void cpuidle_remove_sysfs(struct sys_device *sysdev) +void cpuidle_remove_sysfs(struct cpuidle_device *device) { - int cpu = sysdev->id; - struct cpuidle_device *dev; - - dev = per_cpu(cpuidle_devices, cpu); - kobject_put(&dev->kobj); + kobject_put(&device->kobj); + wait_for_completion(&device->kobj_unregister); } Index: linux.trees.git/drivers/cpuidle/driver.c =================================================================== --- linux.trees.git.orig/drivers/cpuidle/driver.c +++ linux.trees.git/drivers/cpuidle/driver.c @@ -27,10 +27,6 @@ int cpuidle_register_driver(struct cpuid return -EINVAL; spin_lock(&cpuidle_driver_lock); - if (cpuidle_curr_driver) { - spin_unlock(&cpuidle_driver_lock); - return -EBUSY; - } cpuidle_curr_driver = drv; spin_unlock(&cpuidle_driver_lock);