| Message ID | 201109031002.51487.rjw@sisk.pl (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
Hi, On Sat, Sep 3, 2011 at 10:02 AM, Rafael J. Wysocki <rjw@sisk.pl> wrote: > Hi, > > On Saturday, September 03, 2011, Rafael J. Wysocki wrote: >> On Friday, September 02, 2011, Jean Pihet wrote: >> > On Fri, Sep 2, 2011 at 12:07 AM, Rafael J. Wysocki <rjw@sisk.pl> wrote: > ... >> > >> > >> > >> > - mutex_lock(&dev_pm_qos_mtx); >> > >> > req->dev = dev; >> > >> > >> > >> > - /* Return if the device has been removed */ >> > >> > - if (req->dev->power.constraints_state == DEV_PM_QOS_NO_DEVICE) { >> > >> > - ret = -ENODEV; >> > >> > - goto out; >> > >> > - } >> > >> > + device_pm_lock(); >> > >> > + mutex_lock(&dev_pm_qos_mtx); >> > >> > >> > >> > - /* >> > >> > - * Allocate the constraints data on the first call to add_request, >> > >> > - * i.e. only if the data is not already allocated and if the device has >> > >> > - * not been removed >> > >> > - */ >> > >> > - if (dev->power.constraints_state == DEV_PM_QOS_DEVICE_PRESENT) >> > >> > - ret = dev_pm_qos_constraints_allocate(dev); >> > >> > + if (dev->power.constraints) { >> > >> > + device_pm_unlock(); >> > >> > + } else { >> > >> > + if (list_empty(&dev->power.entry)) { >> > >> > + /* The device has been removed from the system. */ >> > >> > + device_pm_unlock(); >> > >> > + goto out; >> > >> 0 is silently returned in case the device has been removed. Is that >> > >> the intention? >> > > >> > > Pretty much it is. Is that a problem? >> > I think the caller needs to know if the constraint has been applied >> > correctly or not. >> >> However, the removal of the device is a special case. What would the caller >> be supposed to do when it learned that the device had been removed while it had >> been trying to add a QoS constraing for it? Not much I guess. > > Anyway, since returning an error code in that case won't hurt either, > below is a v2 of the patch doing that and resetting the dev field in the > req structure. Ok thanks for the update. The comments are inlined below. > > Thanks, > Rafael > > --- > From: Rafael J. Wysocki <rjw@sisk.pl> > Subject: PM / QoS: Add function dev_pm_qos_read_value() (v2) > > To read the current PM QoS value for a given device we need to > make sure that the device's power.constraints object won't be > removed while we're doing that. For this reason, put the > operation under dev->power.lock and acquire the lock > around the initialization and removal of power.constraints. > > Moreover, since we're using the value of power.constraints to > determine whether or not the object is present, the > power.constraints_state field isn't necessary any more and may be > removed. However, dev_pm_qos_add_request() needs to check if the > device is being removed from the system before allocating a new > PM QoS constraints object for it, so it has to use device_pm_lock() > and the device PM QoS initialization and destruction should be done > under device_pm_lock() as well. > > Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> > --- > drivers/base/power/main.c | 4 - > drivers/base/power/qos.c | 170 ++++++++++++++++++++++++++-------------------- > include/linux/pm.h | 8 -- > include/linux/pm_qos.h | 3 > 4 files changed, 104 insertions(+), 81 deletions(-) > > Index: linux/drivers/base/power/qos.c > =================================================================== > --- linux.orig/drivers/base/power/qos.c > +++ linux/drivers/base/power/qos.c > @@ -30,15 +30,6 @@ > * . To minimize the data usage by the per-device constraints, the data struct > * is only allocated at the first call to dev_pm_qos_add_request. > * . The data is later free'd when the device is removed from the system. > - * . The constraints_state variable from dev_pm_info tracks the data struct > - * allocation state: > - * DEV_PM_QOS_NO_DEVICE: No device present or device removed, no data > - * allocated, > - * DEV_PM_QOS_DEVICE_PRESENT: Device present, data not allocated and will be > - * allocated at the first call to dev_pm_qos_add_request, > - * DEV_PM_QOS_ALLOCATED: Device present, data allocated. The per-device > - * PM QoS constraints framework is operational and constraints can be > - * added, updated or removed using the dev_pm_qos_* API. > * . A global mutex protects the constraints users from the data being > * allocated and free'd. > */ > @@ -51,8 +42,30 @@ > > > static DEFINE_MUTEX(dev_pm_qos_mtx); > + > static BLOCKING_NOTIFIER_HEAD(dev_pm_notifiers); > > +/** > + * dev_pm_qos_read_value - Get PM QoS constraint for a given device. > + * @dev: Device to get the PM QoS constraint value for. > + */ > +s32 dev_pm_qos_read_value(struct device *dev) > +{ > + struct pm_qos_constraints *c; > + unsigned long flags; > + s32 ret = 0; > + > + spin_lock_irqsave(&dev->power.lock, flags); > + > + c = dev->power.constraints; > + if (c) > + ret = pm_qos_read_value(c); > + > + spin_unlock_irqrestore(&dev->power.lock, flags); > + > + return ret; > +} > + > /* > * apply_constraint > * @req: constraint request to apply > @@ -105,27 +118,37 @@ static int dev_pm_qos_constraints_alloca > } > BLOCKING_INIT_NOTIFIER_HEAD(n); > > + plist_head_init(&c->list); > + c->target_value = PM_QOS_DEV_LAT_DEFAULT_VALUE; > + c->default_value = PM_QOS_DEV_LAT_DEFAULT_VALUE; > + c->type = PM_QOS_MIN; > + c->notifiers = n; > + > + spin_lock_irq(&dev->power.lock); > dev->power.constraints = c; > - plist_head_init(&dev->power.constraints->list); > - dev->power.constraints->target_value = PM_QOS_DEV_LAT_DEFAULT_VALUE; > - dev->power.constraints->default_value = PM_QOS_DEV_LAT_DEFAULT_VALUE; > - dev->power.constraints->type = PM_QOS_MIN; > - dev->power.constraints->notifiers = n; > - dev->power.constraints_state = DEV_PM_QOS_ALLOCATED; > + spin_unlock_irq(&dev->power.lock); > > return 0; > } > > +static void __dev_pm_qos_constraints_init(struct device *dev) > +{ > + spin_lock_irq(&dev->power.lock); > + dev->power.constraints = NULL; > + spin_unlock_irq(&dev->power.lock); > +} > + > /** > - * dev_pm_qos_constraints_init > + * dev_pm_qos_constraints_init - Initalize device's PM QoS constraints pointer. > * @dev: target device > * > - * Called from the device PM subsystem at device insertion > + * Called from the device PM subsystem at device insertion under > + * device_pm_lock(). > */ > void dev_pm_qos_constraints_init(struct device *dev) > { > mutex_lock(&dev_pm_qos_mtx); > - dev->power.constraints_state = DEV_PM_QOS_DEVICE_PRESENT; > + dev->power.constraints = NULL; > mutex_unlock(&dev_pm_qos_mtx); > } > > @@ -133,34 +156,35 @@ void dev_pm_qos_constraints_init(struct > * dev_pm_qos_constraints_destroy > * @dev: target device > * > - * Called from the device PM subsystem at device removal > + * Called from the device PM subsystem at device removal under device_pm_lock(). > */ > void dev_pm_qos_constraints_destroy(struct device *dev) > { > struct dev_pm_qos_request *req, *tmp; > + struct pm_qos_constraints *c; > > mutex_lock(&dev_pm_qos_mtx); > > - if (dev->power.constraints_state == DEV_PM_QOS_ALLOCATED) { > - /* Flush the constraints list for the device */ > - plist_for_each_entry_safe(req, tmp, > - &dev->power.constraints->list, > - node) { > - /* > - * Update constraints list and call the notification > - * callbacks if needed > - */ > - apply_constraint(req, PM_QOS_REMOVE_REQ, > - PM_QOS_DEFAULT_VALUE); > - memset(req, 0, sizeof(*req)); > - } > + c = dev->power.constraints; > + if (!c) > + goto out; > > - kfree(dev->power.constraints->notifiers); > - kfree(dev->power.constraints); > - dev->power.constraints = NULL; > + /* Flush the constraints list for the device */ > + plist_for_each_entry_safe(req, tmp, &c->list, node) { > + /* > + * Update constraints list and call the notification > + * callbacks if needed > + */ > + apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); > + memset(req, 0, sizeof(*req)); > } > - dev->power.constraints_state = DEV_PM_QOS_NO_DEVICE; > > + __dev_pm_qos_constraints_init(dev); > + > + kfree(c->notifiers); > + kfree(c); > + > + out: > mutex_unlock(&dev_pm_qos_mtx); > } > > @@ -178,8 +202,9 @@ void dev_pm_qos_constraints_destroy(stru > * > * Returns 1 if the aggregated constraint value has changed, > * 0 if the aggregated constraint value has not changed, > - * -EINVAL in case of wrong parameters, -ENODEV if the device has been > - * removed from the system > + * -EINVAL in case of wrong parameters, -ENOMEM if there's not enough memory > + * to allocate for data structures, -ENODEV if the device has just been removed > + * from the system. > */ > int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req, > s32 value) > @@ -195,28 +220,37 @@ int dev_pm_qos_add_request(struct device > return -EINVAL; > } > > - mutex_lock(&dev_pm_qos_mtx); > req->dev = dev; > > - /* Return if the device has been removed */ > - if (req->dev->power.constraints_state == DEV_PM_QOS_NO_DEVICE) { > - ret = -ENODEV; > - goto out; > - } > + device_pm_lock(); > + mutex_lock(&dev_pm_qos_mtx); > > - /* > - * Allocate the constraints data on the first call to add_request, > - * i.e. only if the data is not already allocated and if the device has > - * not been removed > - */ > - if (dev->power.constraints_state == DEV_PM_QOS_DEVICE_PRESENT) > - ret = dev_pm_qos_constraints_allocate(dev); > + if (dev->power.constraints) { > + device_pm_unlock(); > + } else { > + if (list_empty(&dev->power.entry)) { > + /* The device has been removed from the system. */ > + device_pm_unlock(); > + req->dev = NULL; > + ret = -ENODEV; > + goto out; > + } else { > + device_pm_unlock(); > + /* > + * Allocate the constraints data on the first call to > + * add_request, i.e. only if the data is not already > + * allocated and if the device has not been removed. > + */ > + ret = dev_pm_qos_constraints_allocate(dev); > + } > + } > > if (!ret) > ret = apply_constraint(req, PM_QOS_ADD_REQ, value); > > -out: > + out: > mutex_unlock(&dev_pm_qos_mtx); > + > return ret; > } > EXPORT_SYMBOL_GPL(dev_pm_qos_add_request); > @@ -252,13 +286,13 @@ int dev_pm_qos_update_request(struct dev > > mutex_lock(&dev_pm_qos_mtx); > > - if (req->dev->power.constraints_state == DEV_PM_QOS_ALLOCATED) { > + if (req->dev->power.constraints) { > if (new_value != req->node.prio) > ret = apply_constraint(req, PM_QOS_UPDATE_REQ, > new_value); > } else { > /* Return if the device has been removed */ > - ret = -ENODEV; > + ret = -EINVAL; The retcode should be -ENODEV. Is the kerneldoc still OK? > } > > mutex_unlock(&dev_pm_qos_mtx); > @@ -293,7 +327,7 @@ int dev_pm_qos_remove_request(struct dev > > mutex_lock(&dev_pm_qos_mtx); > > - if (req->dev->power.constraints_state == DEV_PM_QOS_ALLOCATED) { > + if (req->dev->power.constraints) { > ret = apply_constraint(req, PM_QOS_REMOVE_REQ, > PM_QOS_DEFAULT_VALUE); > memset(req, 0, sizeof(*req)); > @@ -323,15 +357,12 @@ int dev_pm_qos_add_notifier(struct devic > > mutex_lock(&dev_pm_qos_mtx); > > - /* Silently return if the device has been removed */ > - if (dev->power.constraints_state != DEV_PM_QOS_ALLOCATED) > - goto out; > - > - retval = blocking_notifier_chain_register( > - dev->power.constraints->notifiers, > - notifier); > + /* Silently return if the constraints object is not present. */ > + if (dev->power.constraints) > + retval = blocking_notifier_chain_register( > + dev->power.constraints->notifiers, > + notifier); > > -out: > mutex_unlock(&dev_pm_qos_mtx); > return retval; > } > @@ -354,15 +385,12 @@ int dev_pm_qos_remove_notifier(struct de > > mutex_lock(&dev_pm_qos_mtx); > > - /* Silently return if the device has been removed */ > - if (dev->power.constraints_state != DEV_PM_QOS_ALLOCATED) > - goto out; > - > - retval = blocking_notifier_chain_unregister( > - dev->power.constraints->notifiers, > - notifier); > + /* Silently return if the constraints object is not present. */ > + if (dev->power.constraints) > + retval = blocking_notifier_chain_unregister( > + dev->power.constraints->notifiers, > + notifier); > > -out: > mutex_unlock(&dev_pm_qos_mtx); > return retval; > } > Index: linux/include/linux/pm_qos.h > =================================================================== > --- linux.orig/include/linux/pm_qos.h > +++ linux/include/linux/pm_qos.h > @@ -77,6 +77,7 @@ int pm_qos_remove_notifier(int pm_qos_cl > int pm_qos_request_active(struct pm_qos_request *req); > s32 pm_qos_read_value(struct pm_qos_constraints *c); > > +s32 dev_pm_qos_read_value(struct device *dev); > int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req, > s32 value); > int dev_pm_qos_update_request(struct dev_pm_qos_request *req, s32 new_value); > @@ -117,6 +118,8 @@ static inline int pm_qos_request_active( > static inline s32 pm_qos_read_value(struct pm_qos_constraints *c) > { return 0; } > > +static inline s32 dev_pm_qos_read_value(struct device *dev) > + { return 0; } > static inline int dev_pm_qos_add_request(struct device *dev, > struct dev_pm_qos_request *req, > s32 value) > Index: linux/drivers/base/power/main.c > =================================================================== > --- linux.orig/drivers/base/power/main.c > +++ linux/drivers/base/power/main.c > @@ -98,8 +98,8 @@ void device_pm_add(struct device *dev) > dev_warn(dev, "parent %s should not be sleeping\n", > dev_name(dev->parent)); > list_add_tail(&dev->power.entry, &dpm_list); > - mutex_unlock(&dpm_list_mtx); > dev_pm_qos_constraints_init(dev); > + mutex_unlock(&dpm_list_mtx); > } > > /** > @@ -110,9 +110,9 @@ void device_pm_remove(struct device *dev > { > pr_debug("PM: Removing info for %s:%s\n", > dev->bus ? dev->bus->name : "No Bus", dev_name(dev)); > - dev_pm_qos_constraints_destroy(dev); > complete_all(&dev->power.completion); > mutex_lock(&dpm_list_mtx); > + dev_pm_qos_constraints_destroy(dev); > list_del_init(&dev->power.entry); > mutex_unlock(&dpm_list_mtx); > device_wakeup_disable(dev); > Index: linux/include/linux/pm.h > =================================================================== > --- linux.orig/include/linux/pm.h > +++ linux/include/linux/pm.h > @@ -421,13 +421,6 @@ enum rpm_request { > RPM_REQ_RESUME, > }; > > -/* Per-device PM QoS constraints data struct state */ > -enum dev_pm_qos_state { > - DEV_PM_QOS_NO_DEVICE, /* No device present */ > - DEV_PM_QOS_DEVICE_PRESENT, /* Device present, data not allocated */ > - DEV_PM_QOS_ALLOCATED, /* Device present, data allocated */ > -}; > - > struct wakeup_source; > > struct pm_domain_data { > @@ -489,7 +482,6 @@ struct dev_pm_info { > #endif > struct pm_subsys_data *subsys_data; /* Owned by the subsystem. */ > struct pm_qos_constraints *constraints; > - enum dev_pm_qos_state constraints_state; > }; > > extern void update_pm_runtime_accounting(struct device *dev); > Thanks, Jean -- To unsubscribe from this list: send the line "unsubscribe linux-sh" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Index: linux/drivers/base/power/qos.c =================================================================== --- linux.orig/drivers/base/power/qos.c +++ linux/drivers/base/power/qos.c @@ -30,15 +30,6 @@ * . To minimize the data usage by the per-device constraints, the data struct * is only allocated at the first call to dev_pm_qos_add_request. * . The data is later free'd when the device is removed from the system. - * . The constraints_state variable from dev_pm_info tracks the data struct - * allocation state: - * DEV_PM_QOS_NO_DEVICE: No device present or device removed, no data - * allocated, - * DEV_PM_QOS_DEVICE_PRESENT: Device present, data not allocated and will be - * allocated at the first call to dev_pm_qos_add_request, - * DEV_PM_QOS_ALLOCATED: Device present, data allocated. The per-device - * PM QoS constraints framework is operational and constraints can be - * added, updated or removed using the dev_pm_qos_* API. * . A global mutex protects the constraints users from the data being * allocated and free'd. */ @@ -51,8 +42,30 @@ static DEFINE_MUTEX(dev_pm_qos_mtx); + static BLOCKING_NOTIFIER_HEAD(dev_pm_notifiers); +/** + * dev_pm_qos_read_value - Get PM QoS constraint for a given device. + * @dev: Device to get the PM QoS constraint value for. + */ +s32 dev_pm_qos_read_value(struct device *dev) +{ + struct pm_qos_constraints *c; + unsigned long flags; + s32 ret = 0; + + spin_lock_irqsave(&dev->power.lock, flags); + + c = dev->power.constraints; + if (c) + ret = pm_qos_read_value(c); + + spin_unlock_irqrestore(&dev->power.lock, flags); + + return ret; +} + /* * apply_constraint * @req: constraint request to apply @@ -105,27 +118,37 @@ static int dev_pm_qos_constraints_alloca } BLOCKING_INIT_NOTIFIER_HEAD(n); + plist_head_init(&c->list); + c->target_value = PM_QOS_DEV_LAT_DEFAULT_VALUE; + c->default_value = PM_QOS_DEV_LAT_DEFAULT_VALUE; + c->type = PM_QOS_MIN; + c->notifiers = n; + + spin_lock_irq(&dev->power.lock); dev->power.constraints = c; - plist_head_init(&dev->power.constraints->list); - dev->power.constraints->target_value = PM_QOS_DEV_LAT_DEFAULT_VALUE; - dev->power.constraints->default_value = PM_QOS_DEV_LAT_DEFAULT_VALUE; - dev->power.constraints->type = PM_QOS_MIN; - dev->power.constraints->notifiers = n; - dev->power.constraints_state = DEV_PM_QOS_ALLOCATED; + spin_unlock_irq(&dev->power.lock); return 0; } +static void __dev_pm_qos_constraints_init(struct device *dev) +{ + spin_lock_irq(&dev->power.lock); + dev->power.constraints = NULL; + spin_unlock_irq(&dev->power.lock); +} + /** - * dev_pm_qos_constraints_init + * dev_pm_qos_constraints_init - Initalize device's PM QoS constraints pointer. * @dev: target device * - * Called from the device PM subsystem at device insertion + * Called from the device PM subsystem at device insertion under + * device_pm_lock(). */ void dev_pm_qos_constraints_init(struct device *dev) { mutex_lock(&dev_pm_qos_mtx); - dev->power.constraints_state = DEV_PM_QOS_DEVICE_PRESENT; + dev->power.constraints = NULL; mutex_unlock(&dev_pm_qos_mtx); } @@ -133,34 +156,35 @@ void dev_pm_qos_constraints_init(struct * dev_pm_qos_constraints_destroy * @dev: target device * - * Called from the device PM subsystem at device removal + * Called from the device PM subsystem at device removal under device_pm_lock(). */ void dev_pm_qos_constraints_destroy(struct device *dev) { struct dev_pm_qos_request *req, *tmp; + struct pm_qos_constraints *c; mutex_lock(&dev_pm_qos_mtx); - if (dev->power.constraints_state == DEV_PM_QOS_ALLOCATED) { - /* Flush the constraints list for the device */ - plist_for_each_entry_safe(req, tmp, - &dev->power.constraints->list, - node) { - /* - * Update constraints list and call the notification - * callbacks if needed - */ - apply_constraint(req, PM_QOS_REMOVE_REQ, - PM_QOS_DEFAULT_VALUE); - memset(req, 0, sizeof(*req)); - } + c = dev->power.constraints; + if (!c) + goto out; - kfree(dev->power.constraints->notifiers); - kfree(dev->power.constraints); - dev->power.constraints = NULL; + /* Flush the constraints list for the device */ + plist_for_each_entry_safe(req, tmp, &c->list, node) { + /* + * Update constraints list and call the notification + * callbacks if needed + */ + apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); + memset(req, 0, sizeof(*req)); } - dev->power.constraints_state = DEV_PM_QOS_NO_DEVICE; + __dev_pm_qos_constraints_init(dev); + + kfree(c->notifiers); + kfree(c); + + out: mutex_unlock(&dev_pm_qos_mtx); } @@ -178,8 +202,9 @@ void dev_pm_qos_constraints_destroy(stru * * Returns 1 if the aggregated constraint value has changed, * 0 if the aggregated constraint value has not changed, - * -EINVAL in case of wrong parameters, -ENODEV if the device has been - * removed from the system + * -EINVAL in case of wrong parameters, -ENOMEM if there's not enough memory + * to allocate for data structures, -ENODEV if the device has just been removed + * from the system. */ int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req, s32 value) @@ -195,28 +220,37 @@ int dev_pm_qos_add_request(struct device return -EINVAL; } - mutex_lock(&dev_pm_qos_mtx); req->dev = dev; - /* Return if the device has been removed */ - if (req->dev->power.constraints_state == DEV_PM_QOS_NO_DEVICE) { - ret = -ENODEV; - goto out; - } + device_pm_lock(); + mutex_lock(&dev_pm_qos_mtx); - /* - * Allocate the constraints data on the first call to add_request, - * i.e. only if the data is not already allocated and if the device has - * not been removed - */ - if (dev->power.constraints_state == DEV_PM_QOS_DEVICE_PRESENT) - ret = dev_pm_qos_constraints_allocate(dev); + if (dev->power.constraints) { + device_pm_unlock(); + } else { + if (list_empty(&dev->power.entry)) { + /* The device has been removed from the system. */ + device_pm_unlock(); + req->dev = NULL; + ret = -ENODEV; + goto out; + } else { + device_pm_unlock(); + /* + * Allocate the constraints data on the first call to + * add_request, i.e. only if the data is not already + * allocated and if the device has not been removed. + */ + ret = dev_pm_qos_constraints_allocate(dev); + } + } if (!ret) ret = apply_constraint(req, PM_QOS_ADD_REQ, value); -out: + out: mutex_unlock(&dev_pm_qos_mtx); + return ret; } EXPORT_SYMBOL_GPL(dev_pm_qos_add_request); @@ -252,13 +286,13 @@ int dev_pm_qos_update_request(struct dev mutex_lock(&dev_pm_qos_mtx); - if (req->dev->power.constraints_state == DEV_PM_QOS_ALLOCATED) { + if (req->dev->power.constraints) { if (new_value != req->node.prio) ret = apply_constraint(req, PM_QOS_UPDATE_REQ, new_value); } else { /* Return if the device has been removed */ - ret = -ENODEV; + ret = -EINVAL; } mutex_unlock(&dev_pm_qos_mtx); @@ -293,7 +327,7 @@ int dev_pm_qos_remove_request(struct dev mutex_lock(&dev_pm_qos_mtx); - if (req->dev->power.constraints_state == DEV_PM_QOS_ALLOCATED) { + if (req->dev->power.constraints) { ret = apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); memset(req, 0, sizeof(*req)); @@ -323,15 +357,12 @@ int dev_pm_qos_add_notifier(struct devic mutex_lock(&dev_pm_qos_mtx); - /* Silently return if the device has been removed */ - if (dev->power.constraints_state != DEV_PM_QOS_ALLOCATED) - goto out; - - retval = blocking_notifier_chain_register( - dev->power.constraints->notifiers, - notifier); + /* Silently return if the constraints object is not present. */ + if (dev->power.constraints) + retval = blocking_notifier_chain_register( + dev->power.constraints->notifiers, + notifier); -out: mutex_unlock(&dev_pm_qos_mtx); return retval; } @@ -354,15 +385,12 @@ int dev_pm_qos_remove_notifier(struct de mutex_lock(&dev_pm_qos_mtx); - /* Silently return if the device has been removed */ - if (dev->power.constraints_state != DEV_PM_QOS_ALLOCATED) - goto out; - - retval = blocking_notifier_chain_unregister( - dev->power.constraints->notifiers, - notifier); + /* Silently return if the constraints object is not present. */ + if (dev->power.constraints) + retval = blocking_notifier_chain_unregister( + dev->power.constraints->notifiers, + notifier); -out: mutex_unlock(&dev_pm_qos_mtx); return retval; } Index: linux/include/linux/pm_qos.h =================================================================== --- linux.orig/include/linux/pm_qos.h +++ linux/include/linux/pm_qos.h @@ -77,6 +77,7 @@ int pm_qos_remove_notifier(int pm_qos_cl int pm_qos_request_active(struct pm_qos_request *req); s32 pm_qos_read_value(struct pm_qos_constraints *c); +s32 dev_pm_qos_read_value(struct device *dev); int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req, s32 value); int dev_pm_qos_update_request(struct dev_pm_qos_request *req, s32 new_value); @@ -117,6 +118,8 @@ static inline int pm_qos_request_active( static inline s32 pm_qos_read_value(struct pm_qos_constraints *c) { return 0; } +static inline s32 dev_pm_qos_read_value(struct device *dev) + { return 0; } static inline int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req, s32 value) Index: linux/drivers/base/power/main.c =================================================================== --- linux.orig/drivers/base/power/main.c +++ linux/drivers/base/power/main.c @@ -98,8 +98,8 @@ void device_pm_add(struct device *dev) dev_warn(dev, "parent %s should not be sleeping\n", dev_name(dev->parent)); list_add_tail(&dev->power.entry, &dpm_list); - mutex_unlock(&dpm_list_mtx); dev_pm_qos_constraints_init(dev); + mutex_unlock(&dpm_list_mtx); } /** @@ -110,9 +110,9 @@ void device_pm_remove(struct device *dev { pr_debug("PM: Removing info for %s:%s\n", dev->bus ? dev->bus->name : "No Bus", dev_name(dev)); - dev_pm_qos_constraints_destroy(dev); complete_all(&dev->power.completion); mutex_lock(&dpm_list_mtx); + dev_pm_qos_constraints_destroy(dev); list_del_init(&dev->power.entry); mutex_unlock(&dpm_list_mtx); device_wakeup_disable(dev); Index: linux/include/linux/pm.h =================================================================== --- linux.orig/include/linux/pm.h +++ linux/include/linux/pm.h @@ -421,13 +421,6 @@ enum rpm_request { RPM_REQ_RESUME, }; -/* Per-device PM QoS constraints data struct state */ -enum dev_pm_qos_state { - DEV_PM_QOS_NO_DEVICE, /* No device present */ - DEV_PM_QOS_DEVICE_PRESENT, /* Device present, data not allocated */ - DEV_PM_QOS_ALLOCATED, /* Device present, data allocated */ -}; - struct wakeup_source; struct pm_domain_data { @@ -489,7 +482,6 @@ struct dev_pm_info { #endif struct pm_subsys_data *subsys_data; /* Owned by the subsystem. */ struct pm_qos_constraints *constraints; - enum dev_pm_qos_state constraints_state; }; extern void update_pm_runtime_accounting(struct device *dev);