diff options
Diffstat (limited to 'drivers/base')
| -rw-r--r-- | drivers/base/power/domain.c | 151 | ||||
| -rw-r--r-- | drivers/base/power/domain_governor.c | 166 | ||||
| -rw-r--r-- | drivers/base/power/qos.c | 19 | ||||
| -rw-r--r-- | drivers/base/power/runtime.c | 103 |
4 files changed, 250 insertions, 189 deletions
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 73ce9fb..c3eaa08a 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -11,6 +11,7 @@ #include <linux/io.h> #include <linux/pm_runtime.h> #include <linux/pm_domain.h> +#include <linux/pm_qos.h> #include <linux/slab.h> #include <linux/err.h> #include <linux/sched.h> @@ -38,11 +39,13 @@ ktime_t __start = ktime_get(); \ type __retval = GENPD_DEV_CALLBACK(genpd, type, callback, dev); \ s64 __elapsed = ktime_to_ns(ktime_sub(ktime_get(), __start)); \ - struct generic_pm_domain_data *__gpd_data = dev_gpd_data(dev); \ - if (__elapsed > __gpd_data->td.field) { \ - __gpd_data->td.field = __elapsed; \ + struct gpd_timing_data *__td = &dev_gpd_data(dev)->td; \ + if (!__retval && __elapsed > __td->field) { \ + __td->field = __elapsed; \ dev_warn(dev, name " latency exceeded, new value %lld ns\n", \ __elapsed); \ + genpd->max_off_time_changed = true; \ + __td->constraint_changed = true; \ } \ __retval; \ }) @@ -211,6 +214,7 @@ int __pm_genpd_poweron(struct generic_pm_domain *genpd) elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start)); if (elapsed_ns > genpd->power_on_latency_ns) { genpd->power_on_latency_ns = elapsed_ns; + genpd->max_off_time_changed = true; if (genpd->name) pr_warning("%s: Power-on latency exceeded, " "new value %lld ns\n", genpd->name, @@ -247,6 +251,53 @@ int pm_genpd_poweron(struct generic_pm_domain *genpd) #ifdef CONFIG_PM_RUNTIME +static int genpd_dev_pm_qos_notifier(struct notifier_block *nb, + unsigned long val, void *ptr) +{ + struct generic_pm_domain_data *gpd_data; + 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; + struct pm_domain_data *pdd; + + spin_lock_irq(&dev->power.lock); + + pdd = dev->power.subsys_data ? + dev->power.subsys_data->domain_data : NULL; + if (pdd) { + to_gpd_data(pdd)->td.constraint_changed = true; + genpd = dev_to_genpd(dev); + } else { + genpd = ERR_PTR(-ENODATA); + } + + spin_unlock_irq(&dev->power.lock); + + if (!IS_ERR(genpd)) { + mutex_lock(&genpd->lock); + genpd->max_off_time_changed = true; + mutex_unlock(&genpd->lock); + } + + dev = dev->parent; + if (!dev || dev->power.ignore_children) + break; + } + + return NOTIFY_DONE; +} + /** * __pm_genpd_save_device - Save the pre-suspend state of a device. * @pdd: Domain data of the device to save the state of. @@ -435,6 +486,7 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd) elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start)); if (elapsed_ns > genpd->power_off_latency_ns) { genpd->power_off_latency_ns = elapsed_ns; + genpd->max_off_time_changed = true; if (genpd->name) pr_warning("%s: Power-off latency exceeded, " "new value %lld ns\n", genpd->name, @@ -443,17 +495,6 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd) } genpd->status = GPD_STATE_POWER_OFF; - genpd->power_off_time = ktime_get(); - - /* Update PM QoS information for devices in the domain. */ - list_for_each_entry_reverse(pdd, &genpd->dev_list, list_node) { - struct gpd_timing_data *td = &to_gpd_data(pdd)->td; - - pm_runtime_update_max_time_suspended(pdd->dev, - td->start_latency_ns + - td->restore_state_latency_ns + - genpd->power_on_latency_ns); - } list_for_each_entry(link, &genpd->slave_links, slave_node) { genpd_sd_counter_dec(link->master); @@ -514,9 +555,6 @@ static int pm_genpd_runtime_suspend(struct device *dev) if (ret) return ret; - pm_runtime_update_max_time_suspended(dev, - dev_gpd_data(dev)->td.start_latency_ns); - /* * If power.irq_safe is set, this routine will be run with interrupts * off, so it can't use mutexes. @@ -613,6 +651,12 @@ void pm_genpd_poweroff_unused(void) #else +static inline int genpd_dev_pm_qos_notifier(struct notifier_block *nb, + unsigned long val, void *ptr) +{ + return NOTIFY_DONE; +} + static inline void genpd_power_off_work_fn(struct work_struct *work) {} #define pm_genpd_runtime_suspend NULL @@ -1209,6 +1253,14 @@ 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 = kzalloc(sizeof(*gpd_data), GFP_KERNEL); + if (!gpd_data) + return -ENOMEM; + + mutex_init(&gpd_data->lock); + gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier; + dev_pm_qos_add_notifier(dev, &gpd_data->nb); + genpd_acquire_lock(genpd); if (genpd->status == GPD_STATE_POWER_OFF) { @@ -1227,26 +1279,35 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev, goto out; } - gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL); - if (!gpd_data) { - ret = -ENOMEM; - goto out; - } - genpd->device_count++; + genpd->max_off_time_changed = true; - dev->pm_domain = &genpd->domain; dev_pm_get_subsys_data(dev); + + mutex_lock(&gpd_data->lock); + spin_lock_irq(&dev->power.lock); + dev->pm_domain = &genpd->domain; dev->power.subsys_data->domain_data = &gpd_data->base; gpd_data->base.dev = dev; - gpd_data->need_restore = false; list_add_tail(&gpd_data->base.list_node, &genpd->dev_list); + gpd_data->need_restore = false; if (td) gpd_data->td = *td; + gpd_data->td.constraint_changed = true; + gpd_data->td.effective_constraint_ns = -1; + spin_unlock_irq(&dev->power.lock); + mutex_unlock(&gpd_data->lock); + + genpd_release_lock(genpd); + + return 0; + out: genpd_release_lock(genpd); + dev_pm_qos_remove_notifier(dev, &gpd_data->nb); + kfree(gpd_data); return ret; } @@ -1290,12 +1351,15 @@ int __pm_genpd_of_add_device(struct device_node *genpd_node, struct device *dev, int pm_genpd_remove_device(struct generic_pm_domain *genpd, struct device *dev) { + struct generic_pm_domain_data *gpd_data; struct pm_domain_data *pdd; - int ret = -EINVAL; + int ret = 0; dev_dbg(dev, "%s()\n", __func__); - if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev)) + if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev) + || IS_ERR_OR_NULL(dev->pm_domain) + || pd_to_genpd(dev->pm_domain) != genpd) return -EINVAL; genpd_acquire_lock(genpd); @@ -1305,21 +1369,27 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd, goto out; } - list_for_each_entry(pdd, &genpd->dev_list, list_node) { - if (pdd->dev != dev) - continue; + genpd->device_count--; + genpd->max_off_time_changed = true; - list_del_init(&pdd->list_node); - pdd->dev = NULL; - dev_pm_put_subsys_data(dev); - dev->pm_domain = NULL; - kfree(to_gpd_data(pdd)); + spin_lock_irq(&dev->power.lock); + dev->pm_domain = NULL; + pdd = dev->power.subsys_data->domain_data; + list_del_init(&pdd->list_node); + dev->power.subsys_data->domain_data = NULL; + spin_unlock_irq(&dev->power.lock); - genpd->device_count--; + gpd_data = to_gpd_data(pdd); + mutex_lock(&gpd_data->lock); + pdd->dev = NULL; + mutex_unlock(&gpd_data->lock); - ret = 0; - break; - } + genpd_release_lock(genpd); + + dev_pm_qos_remove_notifier(dev, &gpd_data->nb); + kfree(gpd_data); + dev_pm_put_subsys_data(dev); + return 0; out: genpd_release_lock(genpd); @@ -1378,7 +1448,7 @@ int pm_genpd_add_subdomain(struct generic_pm_domain *genpd, goto out; } - list_for_each_entry(link, &genpd->slave_links, slave_node) { + list_for_each_entry(link, &genpd->master_links, master_node) { if (link->slave == subdomain && link->master == genpd) { ret = -EINVAL; goto out; @@ -1690,6 +1760,7 @@ void pm_genpd_init(struct generic_pm_domain *genpd, genpd->resume_count = 0; genpd->device_count = 0; genpd->max_off_time_ns = -1; + genpd->max_off_time_changed = true; genpd->domain.ops.runtime_suspend = pm_genpd_runtime_suspend; genpd->domain.ops.runtime_resume = pm_genpd_runtime_resume; genpd->domain.ops.runtime_idle = pm_generic_runtime_idle; diff --git a/drivers/base/power/domain_governor.c b/drivers/base/power/domain_governor.c index 66a265b..28dee30 100644 --- a/drivers/base/power/domain_governor.c +++ b/drivers/base/power/domain_governor.c @@ -14,6 +14,31 @@ #ifdef CONFIG_PM_RUNTIME +static int dev_update_qos_constraint(struct device *dev, void *data) +{ + s64 *constraint_ns_p = data; + s32 constraint_ns = -1; + + if (dev->power.subsys_data && dev->power.subsys_data->domain_data) + constraint_ns = dev_gpd_data(dev)->td.effective_constraint_ns; + + if (constraint_ns < 0) { + constraint_ns = dev_pm_qos_read_value(dev); + constraint_ns *= NSEC_PER_USEC; + } + if (constraint_ns == 0) + return 0; + + /* + * constraint_ns cannot be negative here, because the device has been + * suspended. + */ + if (constraint_ns < *constraint_ns_p || *constraint_ns_p == 0) + *constraint_ns_p = constraint_ns; + + return 0; +} + /** * default_stop_ok - Default PM domain governor routine for stopping devices. * @dev: Device to check. @@ -21,14 +46,52 @@ bool default_stop_ok(struct device *dev) { struct gpd_timing_data *td = &dev_gpd_data(dev)->td; + unsigned long flags; + s64 constraint_ns; dev_dbg(dev, "%s()\n", __func__); - if (dev->power.max_time_suspended_ns < 0 || td->break_even_ns == 0) - return true; + spin_lock_irqsave(&dev->power.lock, flags); + + if (!td->constraint_changed) { + bool ret = td->cached_stop_ok; - return td->stop_latency_ns + td->start_latency_ns < td->break_even_ns - && td->break_even_ns < dev->power.max_time_suspended_ns; + spin_unlock_irqrestore(&dev->power.lock, flags); + return ret; + } + td->constraint_changed = false; + td->cached_stop_ok = false; + td->effective_constraint_ns = -1; + constraint_ns = __dev_pm_qos_read_value(dev); + + spin_unlock_irqrestore(&dev->power.lock, flags); + + if (constraint_ns < 0) + return false; + + constraint_ns *= NSEC_PER_USEC; + /* + * We can walk the children without any additional locking, because + * they all have been suspended at this point and their + * effective_constraint_ns fields won't be modified in parallel with us. + */ + if (!dev->power.ignore_children) + device_for_each_child(dev, &constraint_ns, + dev_update_qos_constraint); + + if (constraint_ns > 0) { + constraint_ns -= td->start_latency_ns; + if (constraint_ns == 0) + return false; + } + td->effective_constraint_ns = constraint_ns; + td->cached_stop_ok = constraint_ns > td->stop_latency_ns || + constraint_ns == 0; + /* + * The children have been suspended already, so we don't need to take + * their stop latencies into account here. + */ + return td->cached_stop_ok; } /** @@ -42,9 +105,27 @@ static bool default_power_down_ok(struct dev_pm_domain *pd) struct generic_pm_domain *genpd = pd_to_genpd(pd); struct gpd_link *link; struct pm_domain_data *pdd; - s64 min_dev_off_time_ns; + s64 min_off_time_ns; s64 off_on_time_ns; - ktime_t time_now = ktime_get(); + + if (genpd->max_off_time_changed) { + struct gpd_link *link; + + /* + * We have to invalidate the cached results for the masters, so + * use the observation that default_power_down_ok() is not + * going to be called for any master until this instance + * returns. + */ + list_for_each_entry(link, &genpd->slave_links, slave_node) + link->master->max_off_time_changed = true; + + genpd->max_off_time_changed = false; + genpd->cached_power_down_ok = false; + genpd->max_off_time_ns = -1; + } else { + return genpd->cached_power_down_ok; + } off_on_time_ns = genpd->power_off_latency_ns + genpd->power_on_latency_ns; @@ -61,6 +142,7 @@ static bool default_power_down_ok(struct dev_pm_domain *pd) to_gpd_data(pdd)->td.save_state_latency_ns; } + min_off_time_ns = -1; /* * Check if subdomains can be off for enough time. * @@ -73,8 +155,6 @@ static bool default_power_down_ok(struct dev_pm_domain *pd) if (sd_max_off_ns < 0) continue; - sd_max_off_ns -= ktime_to_ns(ktime_sub(time_now, - sd->power_off_time)); /* * Check if the subdomain is allowed to be off long enough for * the current domain to turn off and on (that's how much time @@ -82,60 +162,64 @@ static bool default_power_down_ok(struct dev_pm_domain *pd) */ if (sd_max_off_ns <= off_on_time_ns) return false; + + if (min_off_time_ns > sd_max_off_ns || min_off_time_ns < 0) + min_off_time_ns = sd_max_off_ns; } /* * Check if the devices in the domain can be off enough time. */ - min_dev_off_time_ns = -1; list_for_each_entry(pdd, &genpd->dev_list, list_node) { struct gpd_timing_data *td; - struct device *dev = pdd->dev; - s64 dev_off_time_ns; + s64 constraint_ns; - if (!dev->driver || dev->power.max_time_suspended_ns < 0) + if (!pdd->dev->driver) continue; + /* + * Check if the device is allowed to be off long enough for the + * domain to turn off and on (that's how much time it will + * have to wait worst case). + */ td = &to_gpd_data(pdd)->td; - dev_off_time_ns = dev->power.max_time_suspended_ns - - (td->start_latency_ns + td->restore_state_latency_ns + - ktime_to_ns(ktime_sub(time_now, - dev->power.suspend_time))); - if (dev_off_time_ns <= off_on_time_ns) - return false; - - if (min_dev_off_time_ns > dev_off_time_ns - || min_dev_off_time_ns < 0) - min_dev_off_time_ns = dev_off_time_ns; - } + constraint_ns = td->effective_constraint_ns; + /* default_stop_ok() need not be called before us. */ + if (constraint_ns < 0) { + constraint_ns = dev_pm_qos_read_value(pdd->dev); + constraint_ns *= NSEC_PER_USEC; + } + if (constraint_ns == 0) + continue; - if (min_dev_off_time_ns < 0) { /* - * There are no latency constraints, so the domain can spend - * arbitrary time in the "off" state. + * constraint_ns cannot be negative here, because the device has + * been suspended. */ - genpd->max_off_time_ns = -1; - return true; + constraint_ns -= td->restore_state_latency_ns; + if (constraint_ns <= off_on_time_ns) + return false; + + if (min_off_time_ns > constraint_ns || min_off_time_ns < 0) + min_off_time_ns = constraint_ns; } + genpd->cached_power_down_ok = true; + /* - * The difference between the computed minimum delta and the time needed - * to turn the domain on is the maximum theoretical time this domain can - * spend in the "off" state. + * If the computed minimum device off time is negative, there are no + * latency constraints, so the domain can spend arbitrary time in the + * "off" state. */ - min_dev_off_time_ns -= genpd->power_on_latency_ns; + if (min_off_time_ns < 0) + return true; /* - * If the difference between the computed minimum delta and the time - * needed to turn the domain off and back on on is smaller than the - * domain's power break even time, removing power from the domain is not - * worth it. + * The difference between the computed minimum subdomain or device off + * time and the time needed to turn the domain on is the maximum + * theoretical time this domain can spend in the "off" state. */ - if (genpd->break_even_ns > - min_dev_off_time_ns - genpd->power_off_latency_ns) - return false; - - genpd->max_off_time_ns = min_dev_off_time_ns; + genpd->max_off_time_ns = min_off_time_ns - genpd->power_on_latency_ns; return true; } diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c index 7185557..fd849a2 100644 --- a/drivers/base/power/qos.c +++ b/drivers/base/power/qos.c @@ -352,21 +352,26 @@ EXPORT_SYMBOL_GPL(dev_pm_qos_remove_request); * * Will register the notifier into a notification chain that gets called * upon changes to the target value for the device. + * + * If the device's constraints object doesn't exist when this routine is called, + * it will be created (or error code will be returned if that fails). */ int dev_pm_qos_add_notifier(struct device *dev, struct notifier_block *notifier) { - int retval = 0; + int ret = 0; mutex_lock(&dev_pm_qos_mtx); - /* Silently return if the constraints object is not present. */ - if (dev->power.constraints) - retval = blocking_notifier_chain_register( - dev->power.constraints->notifiers, - notifier); + if (!dev->power.constraints) + ret = dev->power.power_state.event != PM_EVENT_INVALID ? + dev_pm_qos_constraints_allocate(dev) : -ENODEV; + + if (!ret) + ret = blocking_notifier_chain_register( + dev->power.constraints->notifiers, notifier); mutex_unlock(&dev_pm_qos_mtx); - return retval; + return ret; } EXPORT_SYMBOL_GPL(dev_pm_qos_add_notifier); diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index bd0f394..5989487 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -282,47 +282,6 @@ static int rpm_callback(int (*cb)(struct device *), struct device *dev) return retval != -EACCES ? retval : -EIO; } -struct rpm_qos_data { - ktime_t time_now; - s64 constraint_ns; -}; - -/** - * rpm_update_qos_constraint - Update a given PM QoS constraint data. - * @dev: Device whose timing data to use. - * @data: PM QoS constraint data to update. - * - * Use the suspend timing data of @dev to update PM QoS constraint data pointed - * to by @data. - */ -static int rpm_update_qos_constraint(struct device *dev, void *data) -{ - struct rpm_qos_data *qos = data; - unsigned long flags; - s64 delta_ns; - int ret = 0; - - spin_lock_irqsave(&dev->power.lock, flags); - - if (dev->power.max_time_suspended_ns < 0) - goto out; - - delta_ns = dev->power.max_time_suspended_ns - - ktime_to_ns(ktime_sub(qos->time_now, dev->power.suspend_time)); - if (delta_ns <= 0) { - ret = -EBUSY; - goto out; - } - - if (qos->constraint_ns > delta_ns || qos->constraint_ns == 0) - qos->constraint_ns = delta_ns; - - out: - spin_unlock_irqrestore(&dev->power.lock, flags); - - return ret; -} - /** * rpm_suspend - Carry out runtime suspend of given device. * @dev: Device to suspend. @@ -349,7 +308,6 @@ static int rpm_suspend(struct device *dev, int rpmflags) { int (*callback)(struct device *); struct device *parent = NULL; - struct rpm_qos_data qos; int retval; trace_rpm_suspend(dev, rpmflags); @@ -445,38 +403,14 @@ static int rpm_suspend(struct device *dev, int rpmflags) goto out; } - qos.constraint_ns = __dev_pm_qos_read_value(dev); - if (qos.constraint_ns < 0) { - /* Negative constraint means "never suspend". */ + if (__dev_pm_qos_read_value(dev) < 0) { + /* Negative PM QoS constraint means "never suspend". */ retval = -EPERM; goto out; } - qos.constraint_ns *= NSEC_PER_USEC; - qos.time_now = ktime_get(); __update_runtime_status(dev, RPM_SUSPENDING); - if (!dev->power.ignore_children) { - if (dev->power.irq_safe) - spin_unlock(&dev->power.lock); - else - spin_unlock_irq(&dev->power.lock); - - retval = device_for_each_child(dev, &qos, - rpm_update_qos_constraint); - - if (dev->power.irq_safe) - spin_lock(&dev->power.lock); - else - spin_lock_irq(&dev->power.lock); - - if (retval) - goto fail; - } - - dev->power.suspend_time = qos.time_now; - dev->power.max_time_suspended_ns = qos.constraint_ns ? : -1; - if (dev->pm_domain) callback = dev->pm_domain->ops.runtime_suspend; else if (dev->type && dev->type->pm) @@ -529,8 +463,6 @@ static int rpm_suspend(struct device *dev, int rpmflags) fail: __update_runtime_status(dev, RPM_ACTIVE); - dev->power.suspend_time = ktime_set(0, 0); - dev->power.max_time_suspended_ns = -1; dev->power.deferred_resume = false; wake_up_all(&dev->power.wait_queue); @@ -704,9 +636,6 @@ static int rpm_resume(struct device *dev, int rpmflags) if (dev->power.no_callbacks) goto no_callback; /* Assume success. */ - dev->power.suspend_time = ktime_set(0, 0); - dev->power.max_time_suspended_ns = -1; - __update_runtime_status(dev, RPM_RESUMING); if (dev->pm_domain) @@ -1369,9 +1298,6 @@ void pm_runtime_init(struct device *dev) setup_timer(&dev->power.suspend_timer, pm_suspend_timer_fn, (unsigned long)dev); - dev->power.suspend_time = ktime_set(0, 0); - dev->power.max_time_suspended_ns = -1; - init_waitqueue_head(&dev->power.wait_queue); } @@ -1389,28 +1315,3 @@ void pm_runtime_remove(struct device *dev) if (dev->power.irq_safe && dev->parent) pm_runtime_put_sync(dev->parent); } - -/** - * pm_runtime_update_max_time_suspended - Update device's suspend time data. - * @dev: Device to handle. - * @delta_ns: Value to subtract from the device's max_time_suspended_ns field. - * - * Update the device's power.max_time_suspended_ns field by subtracting - * @delta_ns from it. The resulting value of power.max_time_suspended_ns is - * never negative. - */ -void pm_runtime_update_max_time_suspended(struct device *dev, s64 delta_ns) -{ - unsigned long flags; - - spin_lock_irqsave(&dev->power.lock, flags); - - if (delta_ns > 0 && dev->power.max_time_suspended_ns > 0) { - if (dev->power.max_time_suspended_ns > delta_ns) - dev->power.max_time_suspended_ns -= delta_ns; - else - dev->power.max_time_suspended_ns = 0; - } - - spin_unlock_irqrestore(&dev->power.lock, flags); -} |
