From 382548a62ade2c003c77a1055b6eb2a47ce30084 Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Tue, 20 Jan 2015 11:33:09 +0100 Subject: PM / Domains: Remove pm_genpd_dev_need_restore() API There are currently no users of this API, let's remove it. Additionally, if such feature would be needed future wise, a better option is likely use pm_runtime_set_active|suspended() in some form. Signed-off-by: Ulf Hansson Acked-by: Geert Uytterhoeven Acked-by: Kevin Hilman Signed-off-by: Rafael J. Wysocki --- include/linux/pm_domain.h | 2 -- 1 file changed, 2 deletions(-) (limited to 'include') diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index a9edab2c787a..ed607760fc20 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -140,7 +140,6 @@ extern int __pm_genpd_name_add_device(const char *domain_name, extern int pm_genpd_remove_device(struct generic_pm_domain *genpd, struct device *dev); -extern void pm_genpd_dev_need_restore(struct device *dev, bool val); extern int pm_genpd_add_subdomain(struct generic_pm_domain *genpd, struct generic_pm_domain *new_subdomain); extern int pm_genpd_add_subdomain_names(const char *master_name, @@ -187,7 +186,6 @@ static inline int pm_genpd_remove_device(struct generic_pm_domain *genpd, { return -ENOSYS; } -static inline void pm_genpd_dev_need_restore(struct device *dev, bool val) {} static inline int pm_genpd_add_subdomain(struct generic_pm_domain *genpd, struct generic_pm_domain *new_sd) { -- cgit v1.2.3 From c1dbe2fbb33ef425a81e1a7cffd17c113c87cdbc Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Tue, 27 Jan 2015 21:13:39 +0100 Subject: PM / Domains: Remove reference counting for the generic_pm_domain_data The reference counting was needed when genpd supported PM domain device callbacks. Since this option has been removed, let's also remove the reference counting of the struct generic_pm_domain_data. Signed-off-by: Ulf Hansson Acked-by: Pavel Machek Signed-off-by: Rafael J. Wysocki --- drivers/base/power/domain.c | 10 ++-------- include/linux/pm_domain.h | 1 - 2 files changed, 2 insertions(+), 9 deletions(-) (limited to 'include') diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index f9e7df554b2f..351df5bbd9c9 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -1456,7 +1456,6 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev, gpd_data = gpd_data_new; dev->power.subsys_data->domain_data = &gpd_data->base; } - gpd_data->refcount++; if (td) gpd_data->td = *td; @@ -1504,7 +1503,6 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd, { struct generic_pm_domain_data *gpd_data; struct pm_domain_data *pdd; - bool remove = false; int ret = 0; dev_dbg(dev, "%s()\n", __func__); @@ -1533,10 +1531,7 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd, pdd = dev->power.subsys_data->domain_data; list_del_init(&pdd->list_node); gpd_data = to_gpd_data(pdd); - if (--gpd_data->refcount == 0) { - dev->power.subsys_data->domain_data = NULL; - remove = true; - } + dev->power.subsys_data->domain_data = NULL; spin_unlock_irq(&dev->power.lock); @@ -1547,8 +1542,7 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd, genpd_release_lock(genpd); dev_pm_put_subsys_data(dev); - if (remove) - genpd_free_dev_data(dev, gpd_data); + genpd_free_dev_data(dev, gpd_data); return 0; diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index ed607760fc20..e160a0bba28d 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -114,7 +114,6 @@ struct generic_pm_domain_data { struct gpd_timing_data td; struct notifier_block nb; struct mutex lock; - unsigned int refcount; int need_restore; }; -- cgit v1.2.3 From c0356db7d1b66840882744cbd9d9c5960b2d88c7 Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Tue, 27 Jan 2015 21:13:42 +0100 Subject: PM / Domains: Eliminate the mutex for the generic_pm_domain_data While adding devices to their PM domains, dev_pm_qos_add_notifier() was invoked while allocating the generic_pm_domain_data for the device. Since the generic_pm_domain_data's device pointer will be assigned after allocation, the ->genpd_dev_pm_qos_notifier() callback could be called prior having a valid pointer to the device. Similar scenario existed while removing a device from a genpd. To cope with these scenarios a mutex was used to protect the pointer to the device. By re-order the sequence for when dev_pm_qos_add|remove_notifier() are invoked, we make sure the ->genpd_dev_pm_qos_notifier() callback are always called with a valid device pointer available. In this way, we eliminate the need for protecting the pointer and thus we can remove the mutex from the struct generic_pm_domain_data. Signed-off-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki --- drivers/base/power/domain.c | 37 ++++++++++++++----------------------- include/linux/pm_domain.h | 1 - 2 files changed, 14 insertions(+), 24 deletions(-) (limited to 'include') diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 88198ba919d9..1f026c18bc5c 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -344,14 +344,7 @@ static int genpd_dev_pm_qos_notifier(struct notifier_block *nb, struct device *dev; gpd_data = container_of(nb, struct generic_pm_domain_data, nb); - - mutex_lock(&gpd_data->lock); dev = gpd_data->base.dev; - if (!dev) { - mutex_unlock(&gpd_data->lock); - return NOTIFY_DONE; - } - mutex_unlock(&gpd_data->lock); for (;;) { struct generic_pm_domain *genpd; @@ -1392,16 +1385,12 @@ static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev) if (!gpd_data) return NULL; - mutex_init(&gpd_data->lock); - gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier; - dev_pm_qos_add_notifier(dev, &gpd_data->nb); return gpd_data; } static void genpd_free_dev_data(struct device *dev, struct generic_pm_domain_data *gpd_data) { - dev_pm_qos_remove_notifier(dev, &gpd_data->nb); kfree(gpd_data); } @@ -1414,7 +1403,7 @@ static void genpd_free_dev_data(struct device *dev, int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev, struct gpd_timing_data *td) { - struct generic_pm_domain_data *gpd_data_new, *gpd_data = NULL; + struct generic_pm_domain_data *gpd_data; int ret = 0; dev_dbg(dev, "%s()\n", __func__); @@ -1422,8 +1411,8 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev, if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev)) return -EINVAL; - gpd_data_new = genpd_alloc_dev_data(dev); - if (!gpd_data_new) + gpd_data = genpd_alloc_dev_data(dev); + if (!gpd_data) return -ENOMEM; genpd_acquire_lock(genpd); @@ -1445,7 +1434,6 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev, goto out; } - gpd_data = gpd_data_new; dev->power.subsys_data->domain_data = &gpd_data->base; if (td) @@ -1461,19 +1449,20 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev, genpd->device_count++; genpd->max_off_time_changed = true; - mutex_lock(&gpd_data->lock); gpd_data->base.dev = dev; list_add_tail(&gpd_data->base.list_node, &genpd->dev_list); gpd_data->need_restore = -1; gpd_data->td.constraint_changed = true; gpd_data->td.effective_constraint_ns = -1; - mutex_unlock(&gpd_data->lock); + gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier; out: genpd_release_lock(genpd); - if (gpd_data != gpd_data_new) - genpd_free_dev_data(dev, gpd_data_new); + if (ret) + genpd_free_dev_data(dev, gpd_data); + else + dev_pm_qos_add_notifier(dev, &gpd_data->nb); return ret; } @@ -1509,6 +1498,11 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd, || pd_to_genpd(dev->pm_domain) != genpd) return -EINVAL; + /* The above validation also means we have existing domain_data. */ + pdd = dev->power.subsys_data->domain_data; + gpd_data = to_gpd_data(pdd); + dev_pm_qos_remove_notifier(dev, &gpd_data->nb); + genpd_acquire_lock(genpd); if (genpd->prepared_count > 0) { @@ -1525,16 +1519,12 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd, spin_lock_irq(&dev->power.lock); dev->pm_domain = NULL; - pdd = dev->power.subsys_data->domain_data; list_del_init(&pdd->list_node); - gpd_data = to_gpd_data(pdd); dev->power.subsys_data->domain_data = NULL; spin_unlock_irq(&dev->power.lock); - mutex_lock(&gpd_data->lock); pdd->dev = NULL; - mutex_unlock(&gpd_data->lock); genpd_release_lock(genpd); @@ -1545,6 +1535,7 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd, out: genpd_release_lock(genpd); + dev_pm_qos_add_notifier(dev, &gpd_data->nb); return ret; } diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index e160a0bba28d..080e778118ba 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -113,7 +113,6 @@ struct generic_pm_domain_data { struct pm_domain_data base; struct gpd_timing_data td; struct notifier_block nb; - struct mutex lock; int need_restore; }; -- cgit v1.2.3 From 1e95e3b2da424db68d0a465273f1901a990c6277 Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Thu, 29 Jan 2015 18:39:05 +0100 Subject: PM: Convert dev_pm_put_subsys_data() into a void function Clients using the dev_pm_put_subsys_data() API isn't interested of a return value. They care only of decreasing a reference to the device's pm_subsys_data. So, let's convert the API to a void function, which anyway seems like reasonable thing to do. Signed-off-by: Ulf Hansson Acked-by: Geert Uytterhoeven Signed-off-by: Rafael J. Wysocki --- drivers/base/power/common.c | 14 ++++---------- include/linux/pm.h | 2 +- 2 files changed, 5 insertions(+), 11 deletions(-) (limited to 'include') diff --git a/drivers/base/power/common.c b/drivers/base/power/common.c index a1ee51d43da1..f32b802b98f4 100644 --- a/drivers/base/power/common.c +++ b/drivers/base/power/common.c @@ -56,13 +56,11 @@ EXPORT_SYMBOL_GPL(dev_pm_get_subsys_data); * @dev: Device to handle. * * If the reference counter of power.subsys_data is zero after dropping the - * reference, power.subsys_data is removed. Return 1 if that happens or 0 - * otherwise. + * reference, power.subsys_data is removed. */ -int dev_pm_put_subsys_data(struct device *dev) +void dev_pm_put_subsys_data(struct device *dev) { struct pm_subsys_data *psd; - int ret = 1; spin_lock_irq(&dev->power.lock); @@ -70,18 +68,14 @@ int dev_pm_put_subsys_data(struct device *dev) if (!psd) goto out; - if (--psd->refcount == 0) { + if (--psd->refcount == 0) dev->power.subsys_data = NULL; - } else { + else psd = NULL; - ret = 0; - } out: spin_unlock_irq(&dev->power.lock); kfree(psd); - - return ret; } EXPORT_SYMBOL_GPL(dev_pm_put_subsys_data); diff --git a/include/linux/pm.h b/include/linux/pm.h index 8b5976364619..e2f1be6dd9dd 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -597,7 +597,7 @@ struct dev_pm_info { extern void update_pm_runtime_accounting(struct device *dev); extern int dev_pm_get_subsys_data(struct device *dev); -extern int dev_pm_put_subsys_data(struct device *dev); +extern void dev_pm_put_subsys_data(struct device *dev); /* * Power domains provide callbacks that are executed during system suspend, -- cgit v1.2.3