diff options
Diffstat (limited to 'drivers/base/power/main.c')
| -rw-r--r-- | drivers/base/power/main.c | 538 |
1 files changed, 439 insertions, 99 deletions
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 4a67e83300e1..c883b01ffbdd 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -63,8 +63,23 @@ static LIST_HEAD(dpm_noirq_list); static DEFINE_MUTEX(dpm_list_mtx); static pm_message_t pm_transition; +static DEFINE_MUTEX(async_wip_mtx); static int async_error; +/** + * pm_hibernate_is_recovering - if recovering from hibernate due to error. + * + * Used to query if dev_pm_ops.thaw() is called for normal hibernation case or + * recovering from some error. + * + * Return: true for error case, false for normal case. + */ +bool pm_hibernate_is_recovering(void) +{ + return pm_transition.event == PM_EVENT_RECOVER; +} +EXPORT_SYMBOL_GPL(pm_hibernate_is_recovering); + static const char *pm_verb(int event) { switch (event) { @@ -249,7 +264,7 @@ static int dpm_wait_fn(struct device *dev, void *async_ptr) static void dpm_wait_for_children(struct device *dev, bool async) { - device_for_each_child(dev, &async, dpm_wait_fn); + device_for_each_child(dev, &async, dpm_wait_fn); } static void dpm_wait_for_suppliers(struct device *dev, bool async) @@ -496,6 +511,7 @@ struct dpm_watchdog { struct device *dev; struct task_struct *tsk; struct timer_list timer; + bool fatal; }; #define DECLARE_DPM_WATCHDOG_ON_STACK(wd) \ @@ -511,12 +527,24 @@ struct dpm_watchdog { */ static void dpm_watchdog_handler(struct timer_list *t) { - struct dpm_watchdog *wd = from_timer(wd, t, timer); + struct dpm_watchdog *wd = timer_container_of(wd, t, timer); + struct timer_list *timer = &wd->timer; + unsigned int time_left; + + if (wd->fatal) { + dev_emerg(wd->dev, "**** DPM device timeout ****\n"); + show_stack(wd->tsk, NULL, KERN_EMERG); + panic("%s %s: unrecoverable failure\n", + dev_driver_string(wd->dev), dev_name(wd->dev)); + } - dev_emerg(wd->dev, "**** DPM device timeout ****\n"); - show_stack(wd->tsk, NULL, KERN_EMERG); - panic("%s %s: unrecoverable failure\n", - dev_driver_string(wd->dev), dev_name(wd->dev)); + time_left = CONFIG_DPM_WATCHDOG_TIMEOUT - CONFIG_DPM_WATCHDOG_WARNING_TIMEOUT; + dev_warn(wd->dev, "**** DPM device timeout after %u seconds; %u seconds until panic ****\n", + CONFIG_DPM_WATCHDOG_WARNING_TIMEOUT, time_left); + show_stack(wd->tsk, NULL, KERN_WARNING); + + wd->fatal = true; + mod_timer(timer, jiffies + HZ * time_left); } /** @@ -530,10 +558,11 @@ static void dpm_watchdog_set(struct dpm_watchdog *wd, struct device *dev) wd->dev = dev; wd->tsk = current; + wd->fatal = CONFIG_DPM_WATCHDOG_TIMEOUT == CONFIG_DPM_WATCHDOG_WARNING_TIMEOUT; timer_setup_on_stack(timer, dpm_watchdog_handler, 0); /* use same timeout value for both suspend and resume */ - timer->expires = jiffies + HZ * CONFIG_DPM_WATCHDOG_TIMEOUT; + timer->expires = jiffies + HZ * CONFIG_DPM_WATCHDOG_WARNING_TIMEOUT; add_timer(timer); } @@ -545,8 +574,8 @@ static void dpm_watchdog_clear(struct dpm_watchdog *wd) { struct timer_list *timer = &wd->timer; - del_timer_sync(timer); - destroy_timer_on_stack(timer); + timer_delete_sync(timer); + timer_destroy_on_stack(timer); } #else #define DECLARE_DPM_WATCHDOG_ON_STACK(wd) @@ -583,29 +612,96 @@ static bool is_async(struct device *dev) && !pm_trace_is_enabled(); } +static bool __dpm_async(struct device *dev, async_func_t func) +{ + if (dev->power.work_in_progress) + return true; + + if (!is_async(dev)) + return false; + + dev->power.work_in_progress = true; + + get_device(dev); + + if (async_schedule_dev_nocall(func, dev)) + return true; + + put_device(dev); + + return false; +} + static bool dpm_async_fn(struct device *dev, async_func_t func) { - reinit_completion(&dev->power.completion); + guard(mutex)(&async_wip_mtx); - if (is_async(dev)) { - dev->power.async_in_progress = true; + return __dpm_async(dev, func); +} - get_device(dev); +static int dpm_async_with_cleanup(struct device *dev, void *fn) +{ + guard(mutex)(&async_wip_mtx); - if (async_schedule_dev_nocall(func, dev)) - return true; + if (!__dpm_async(dev, fn)) + dev->power.work_in_progress = false; - put_device(dev); - } + return 0; +} + +static void dpm_async_resume_children(struct device *dev, async_func_t func) +{ /* - * Because async_schedule_dev_nocall() above has returned false or it - * has not been called at all, func() is not running and it is safe to - * update the async_in_progress flag without extra synchronization. + * Prevent racing with dpm_clear_async_state() during initial list + * walks in dpm_noirq_resume_devices(), dpm_resume_early(), and + * dpm_resume(). */ - dev->power.async_in_progress = false; - return false; + guard(mutex)(&dpm_list_mtx); + + /* + * Start processing "async" children of the device unless it's been + * started already for them. + */ + device_for_each_child(dev, func, dpm_async_with_cleanup); +} + +static void dpm_async_resume_subordinate(struct device *dev, async_func_t func) +{ + struct device_link *link; + int idx; + + dpm_async_resume_children(dev, func); + + idx = device_links_read_lock(); + + /* Start processing the device's "async" consumers. */ + list_for_each_entry_rcu_locked(link, &dev->links.consumers, s_node) + if (READ_ONCE(link->status) != DL_STATE_DORMANT) + dpm_async_with_cleanup(link->consumer, func); + + device_links_read_unlock(idx); } +static void dpm_clear_async_state(struct device *dev) +{ + reinit_completion(&dev->power.completion); + dev->power.work_in_progress = false; +} + +static bool dpm_root_device(struct device *dev) +{ + lockdep_assert_held(&dpm_list_mtx); + + /* + * Since this function is required to run under dpm_list_mtx, the + * list_empty() below will only return true if the device's list of + * consumers is actually empty before calling it. + */ + return !dev->parent && list_empty(&dev->links.suppliers); +} + +static void async_resume_noirq(void *data, async_cookie_t cookie); + /** * device_resume_noirq - Execute a "noirq resume" callback for given device. * @dev: Device to handle. @@ -628,8 +724,20 @@ static void device_resume_noirq(struct device *dev, pm_message_t state, bool asy if (dev->power.syscore || dev->power.direct_complete) goto Out; - if (!dev->power.is_noirq_suspended) + if (!dev->power.is_noirq_suspended) { + /* + * This means that system suspend has been aborted in the noirq + * phase before invoking the noirq suspend callback for the + * device, so if device_suspend_late() has left it in suspend, + * device_resume_early() should leave it in suspend either in + * case the early resume of it depends on the noirq resume that + * has not run. + */ + if (dev_pm_skip_suspend(dev)) + dev->power.must_resume = false; + goto Out; + } if (!dpm_wait_for_superior(dev, async)) goto Out; @@ -642,12 +750,12 @@ static void device_resume_noirq(struct device *dev, pm_message_t state, bool asy * so change its status accordingly. * * Otherwise, the device is going to be resumed, so set its PM-runtime - * status to "active", but do that only if DPM_FLAG_SMART_SUSPEND is set - * to avoid confusing drivers that don't use it. + * status to "active" unless its power.smart_suspend flag is clear, in + * which case it is not necessary to update its PM-runtime status. */ if (skip_resume) pm_runtime_set_suspended(dev); - else if (dev_pm_skip_suspend(dev)) + else if (dev_pm_smart_suspend(dev)) pm_runtime_set_active(dev); if (dev->pm_domain) { @@ -685,10 +793,12 @@ Out: TRACE_RESUME(error); if (error) { - async_error = error; + WRITE_ONCE(async_error, error); dpm_save_failed_dev(dev_name(dev)); pm_dev_err(dev, state, async ? " async noirq" : " noirq", error); } + + dpm_async_resume_subordinate(dev, async_resume_noirq); } static void async_resume_noirq(void *data, async_cookie_t cookie) @@ -712,17 +822,20 @@ static void dpm_noirq_resume_devices(pm_message_t state) mutex_lock(&dpm_list_mtx); /* - * Trigger the resume of "async" devices upfront so they don't have to - * wait for the "non-async" ones they don't depend on. + * Start processing "async" root devices upfront so they don't wait for + * the "sync" devices they don't depend on. */ - list_for_each_entry(dev, &dpm_noirq_list, power.entry) - dpm_async_fn(dev, async_resume_noirq); + list_for_each_entry(dev, &dpm_noirq_list, power.entry) { + dpm_clear_async_state(dev); + if (dpm_root_device(dev)) + dpm_async_with_cleanup(dev, async_resume_noirq); + } while (!list_empty(&dpm_noirq_list)) { dev = to_device(dpm_noirq_list.next); list_move_tail(&dev->power.entry, &dpm_late_early_list); - if (!dev->power.async_in_progress) { + if (!dpm_async_fn(dev, async_resume_noirq)) { get_device(dev); mutex_unlock(&dpm_list_mtx); @@ -737,7 +850,7 @@ static void dpm_noirq_resume_devices(pm_message_t state) mutex_unlock(&dpm_list_mtx); async_synchronize_full(); dpm_show_time(starttime, state, 0, "noirq"); - if (async_error) + if (READ_ONCE(async_error)) dpm_save_failed_step(SUSPEND_RESUME_NOIRQ); trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, false); @@ -758,6 +871,8 @@ void dpm_resume_noirq(pm_message_t state) device_wakeup_disarm_wake_irqs(); } +static void async_resume_early(void *data, async_cookie_t cookie); + /** * device_resume_early - Execute an "early resume" callback for given device. * @dev: Device to handle. @@ -821,10 +936,12 @@ Out: complete_all(&dev->power.completion); if (error) { - async_error = error; + WRITE_ONCE(async_error, error); dpm_save_failed_dev(dev_name(dev)); pm_dev_err(dev, state, async ? " async early" : " early", error); } + + dpm_async_resume_subordinate(dev, async_resume_early); } static void async_resume_early(void *data, async_cookie_t cookie) @@ -852,17 +969,20 @@ void dpm_resume_early(pm_message_t state) mutex_lock(&dpm_list_mtx); /* - * Trigger the resume of "async" devices upfront so they don't have to - * wait for the "non-async" ones they don't depend on. + * Start processing "async" root devices upfront so they don't wait for + * the "sync" devices they don't depend on. */ - list_for_each_entry(dev, &dpm_late_early_list, power.entry) - dpm_async_fn(dev, async_resume_early); + list_for_each_entry(dev, &dpm_late_early_list, power.entry) { + dpm_clear_async_state(dev); + if (dpm_root_device(dev)) + dpm_async_with_cleanup(dev, async_resume_early); + } while (!list_empty(&dpm_late_early_list)) { dev = to_device(dpm_late_early_list.next); list_move_tail(&dev->power.entry, &dpm_suspended_list); - if (!dev->power.async_in_progress) { + if (!dpm_async_fn(dev, async_resume_early)) { get_device(dev); mutex_unlock(&dpm_list_mtx); @@ -877,7 +997,7 @@ void dpm_resume_early(pm_message_t state) mutex_unlock(&dpm_list_mtx); async_synchronize_full(); dpm_show_time(starttime, state, 0, "early"); - if (async_error) + if (READ_ONCE(async_error)) dpm_save_failed_step(SUSPEND_RESUME_EARLY); trace_suspend_resume(TPS("dpm_resume_early"), state.event, false); @@ -894,6 +1014,8 @@ void dpm_resume_start(pm_message_t state) } EXPORT_SYMBOL_GPL(dpm_resume_start); +static void async_resume(void *data, async_cookie_t cookie); + /** * device_resume - Execute "resume" callbacks for given device. * @dev: Device to handle. @@ -913,8 +1035,20 @@ static void device_resume(struct device *dev, pm_message_t state, bool async) if (dev->power.syscore) goto Complete; + if (!dev->power.is_suspended) + goto Complete; + + dev->power.is_suspended = false; + if (dev->power.direct_complete) { - /* Match the pm_runtime_disable() in __device_suspend(). */ + /* + * Allow new children to be added under the device after this + * point if it has no PM callbacks. + */ + if (dev->power.no_pm_callbacks) + dev->power.is_prepared = false; + + /* Match the pm_runtime_disable() in device_suspend(). */ pm_runtime_enable(dev); goto Complete; } @@ -931,9 +1065,6 @@ static void device_resume(struct device *dev, pm_message_t state, bool async) */ dev->power.is_prepared = false; - if (!dev->power.is_suspended) - goto Unlock; - if (dev->pm_domain) { info = "power domain "; callback = pm_op(&dev->pm_domain->ops, state); @@ -971,9 +1102,7 @@ static void device_resume(struct device *dev, pm_message_t state, bool async) End: error = dpm_run_callback(callback, dev, state, info); - dev->power.is_suspended = false; - Unlock: device_unlock(dev); dpm_watchdog_clear(&wd); @@ -983,10 +1112,12 @@ static void device_resume(struct device *dev, pm_message_t state, bool async) TRACE_RESUME(error); if (error) { - async_error = error; + WRITE_ONCE(async_error, error); dpm_save_failed_dev(dev_name(dev)); pm_dev_err(dev, state, async ? " async" : "", error); } + + dpm_async_resume_subordinate(dev, async_resume); } static void async_resume(void *data, async_cookie_t cookie) @@ -1010,7 +1141,6 @@ void dpm_resume(pm_message_t state) ktime_t starttime = ktime_get(); trace_suspend_resume(TPS("dpm_resume"), state.event, true); - might_sleep(); pm_transition = state; async_error = 0; @@ -1018,17 +1148,20 @@ void dpm_resume(pm_message_t state) mutex_lock(&dpm_list_mtx); /* - * Trigger the resume of "async" devices upfront so they don't have to - * wait for the "non-async" ones they don't depend on. + * Start processing "async" root devices upfront so they don't wait for + * the "sync" devices they don't depend on. */ - list_for_each_entry(dev, &dpm_suspended_list, power.entry) - dpm_async_fn(dev, async_resume); + list_for_each_entry(dev, &dpm_suspended_list, power.entry) { + dpm_clear_async_state(dev); + if (dpm_root_device(dev)) + dpm_async_with_cleanup(dev, async_resume); + } while (!list_empty(&dpm_suspended_list)) { dev = to_device(dpm_suspended_list.next); list_move_tail(&dev->power.entry, &dpm_prepared_list); - if (!dev->power.async_in_progress) { + if (!dpm_async_fn(dev, async_resume)) { get_device(dev); mutex_unlock(&dpm_list_mtx); @@ -1043,7 +1176,7 @@ void dpm_resume(pm_message_t state) mutex_unlock(&dpm_list_mtx); async_synchronize_full(); dpm_show_time(starttime, state, 0, NULL); - if (async_error) + if (READ_ONCE(async_error)) dpm_save_failed_step(SUSPEND_RESUME); cpufreq_resume(); @@ -1093,6 +1226,8 @@ static void device_complete(struct device *dev, pm_message_t state) device_unlock(dev); out: + /* If enabling runtime PM for the device is blocked, unblock it. */ + pm_runtime_unblock(dev); pm_runtime_put(dev); } @@ -1108,7 +1243,6 @@ void dpm_complete(pm_message_t state) struct list_head list; trace_suspend_resume(TPS("dpm_complete"), state.event, true); - might_sleep(); INIT_LIST_HEAD(&list); mutex_lock(&dpm_list_mtx); @@ -1147,6 +1281,7 @@ void dpm_complete(pm_message_t state) void dpm_resume_end(pm_message_t state) { dpm_resume(state); + pm_restore_gfp_mask(); dpm_complete(state); } EXPORT_SYMBOL_GPL(dpm_resume_end); @@ -1154,6 +1289,82 @@ EXPORT_SYMBOL_GPL(dpm_resume_end); /*------------------------- Suspend routines -------------------------*/ +static bool dpm_leaf_device(struct device *dev) +{ + struct device *child; + + lockdep_assert_held(&dpm_list_mtx); + + child = device_find_any_child(dev); + if (child) { + put_device(child); + + return false; + } + + /* + * Since this function is required to run under dpm_list_mtx, the + * list_empty() below will only return true if the device's list of + * consumers is actually empty before calling it. + */ + return list_empty(&dev->links.consumers); +} + +static bool dpm_async_suspend_parent(struct device *dev, async_func_t func) +{ + guard(mutex)(&dpm_list_mtx); + + /* + * If the device is suspended asynchronously and the parent's callback + * deletes both the device and the parent itself, the parent object may + * be freed while this function is running, so avoid that by checking + * if the device has been deleted already as the parent cannot be + * deleted before it. + */ + if (!device_pm_initialized(dev)) + return false; + + /* Start processing the device's parent if it is "async". */ + if (dev->parent) + dpm_async_with_cleanup(dev->parent, func); + + return true; +} + +static void dpm_async_suspend_superior(struct device *dev, async_func_t func) +{ + struct device_link *link; + int idx; + + if (!dpm_async_suspend_parent(dev, func)) + return; + + idx = device_links_read_lock(); + + /* Start processing the device's "async" suppliers. */ + list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node) + if (READ_ONCE(link->status) != DL_STATE_DORMANT) + dpm_async_with_cleanup(link->supplier, func); + + device_links_read_unlock(idx); +} + +static void dpm_async_suspend_complete_all(struct list_head *device_list) +{ + struct device *dev; + + guard(mutex)(&async_wip_mtx); + + list_for_each_entry_reverse(dev, device_list, power.entry) { + /* + * In case the device is being waited for and async processing + * has not started for it yet, let the waiters make progress. + */ + if (!dev->power.work_in_progress) + complete_all(&dev->power.completion); + } +} + /** * resume_event - Return a "resume" message for given "suspend" sleep state. * @sleep_state: PM message representing a sleep state. @@ -1191,6 +1402,8 @@ static void dpm_superior_set_must_resume(struct device *dev) device_links_read_unlock(idx); } +static void async_suspend_noirq(void *data, async_cookie_t cookie); + /** * device_suspend_noirq - Execute a "noirq suspend" callback for given device. * @dev: Device to handle. @@ -1200,7 +1413,7 @@ static void dpm_superior_set_must_resume(struct device *dev) * The driver of @dev will not receive interrupts while this function is being * executed. */ -static int device_suspend_noirq(struct device *dev, pm_message_t state, bool async) +static void device_suspend_noirq(struct device *dev, pm_message_t state, bool async) { pm_callback_t callback = NULL; const char *info = NULL; @@ -1211,7 +1424,7 @@ static int device_suspend_noirq(struct device *dev, pm_message_t state, bool asy dpm_wait_for_subordinate(dev, async); - if (async_error) + if (READ_ONCE(async_error)) goto Complete; if (dev->power.syscore || dev->power.direct_complete) @@ -1244,7 +1457,7 @@ static int device_suspend_noirq(struct device *dev, pm_message_t state, bool asy Run: error = dpm_run_callback(callback, dev, state, info); if (error) { - async_error = error; + WRITE_ONCE(async_error, error); dpm_save_failed_dev(dev_name(dev)); pm_dev_err(dev, state, async ? " async noirq" : " noirq", error); goto Complete; @@ -1254,14 +1467,13 @@ Skip: dev->power.is_noirq_suspended = true; /* - * Skipping the resume of devices that were in use right before the - * system suspend (as indicated by their PM-runtime usage counters) - * would be suboptimal. Also resume them if doing that is not allowed - * to be skipped. + * Devices must be resumed unless they are explicitly allowed to be left + * in suspend, but even in that case skipping the resume of devices that + * were in use right before the system suspend (as indicated by their + * runtime PM usage counters and child counters) would be suboptimal. */ - if (atomic_read(&dev->power.usage_count) > 1 || - !(dev_pm_test_driver_flags(dev, DPM_FLAG_MAY_SKIP_RESUME) && - dev->power.may_skip_resume)) + if (!(dev_pm_test_driver_flags(dev, DPM_FLAG_MAY_SKIP_RESUME) && + dev->power.may_skip_resume) || !pm_runtime_need_not_resume(dev)) dev->power.must_resume = true; if (dev->power.must_resume) @@ -1270,7 +1482,11 @@ Skip: Complete: complete_all(&dev->power.completion); TRACE_SUSPEND(error); - return error; + + if (error || READ_ONCE(async_error)) + return; + + dpm_async_suspend_superior(dev, async_suspend_noirq); } static void async_suspend_noirq(void *data, async_cookie_t cookie) @@ -1284,7 +1500,8 @@ static void async_suspend_noirq(void *data, async_cookie_t cookie) static int dpm_noirq_suspend_devices(pm_message_t state) { ktime_t starttime = ktime_get(); - int error = 0; + struct device *dev; + int error; trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, true); @@ -1293,8 +1510,18 @@ static int dpm_noirq_suspend_devices(pm_message_t state) mutex_lock(&dpm_list_mtx); + /* + * Start processing "async" leaf devices upfront so they don't need to + * wait for the "sync" devices they don't depend on. + */ + list_for_each_entry_reverse(dev, &dpm_late_early_list, power.entry) { + dpm_clear_async_state(dev); + if (dpm_leaf_device(dev)) + dpm_async_with_cleanup(dev, async_suspend_noirq); + } + while (!list_empty(&dpm_late_early_list)) { - struct device *dev = to_device(dpm_late_early_list.prev); + dev = to_device(dpm_late_early_list.prev); list_move(&dev->power.entry, &dpm_noirq_list); @@ -1305,22 +1532,28 @@ static int dpm_noirq_suspend_devices(pm_message_t state) mutex_unlock(&dpm_list_mtx); - error = device_suspend_noirq(dev, state, false); + device_suspend_noirq(dev, state, false); put_device(dev); mutex_lock(&dpm_list_mtx); - if (error || async_error) + if (READ_ONCE(async_error)) { + dpm_async_suspend_complete_all(&dpm_late_early_list); + /* + * Move all devices to the target list to resume them + * properly. + */ + list_splice_init(&dpm_late_early_list, &dpm_noirq_list); break; + } } mutex_unlock(&dpm_list_mtx); async_synchronize_full(); - if (!error) - error = async_error; + error = READ_ONCE(async_error); if (error) dpm_save_failed_step(SUSPEND_SUSPEND_NOIRQ); @@ -1365,6 +1598,8 @@ static void dpm_propagate_wakeup_to_parent(struct device *dev) spin_unlock_irq(&parent->power.lock); } +static void async_suspend_late(void *data, async_cookie_t cookie); + /** * device_suspend_late - Execute a "late suspend" callback for given device. * @dev: Device to handle. @@ -1373,7 +1608,7 @@ static void dpm_propagate_wakeup_to_parent(struct device *dev) * * Runtime PM is disabled for @dev while this function is being executed. */ -static int device_suspend_late(struct device *dev, pm_message_t state, bool async) +static void device_suspend_late(struct device *dev, pm_message_t state, bool async) { pm_callback_t callback = NULL; const char *info = NULL; @@ -1382,15 +1617,19 @@ static int device_suspend_late(struct device *dev, pm_message_t state, bool asyn TRACE_DEVICE(dev); TRACE_SUSPEND(0); + /* + * Disable runtime PM for the device without checking if there is a + * pending resume request for it. + */ __pm_runtime_disable(dev, false); dpm_wait_for_subordinate(dev, async); - if (async_error) + if (READ_ONCE(async_error)) goto Complete; if (pm_wakeup_pending()) { - async_error = -EBUSY; + WRITE_ONCE(async_error, -EBUSY); goto Complete; } @@ -1424,7 +1663,7 @@ static int device_suspend_late(struct device *dev, pm_message_t state, bool asyn Run: error = dpm_run_callback(callback, dev, state, info); if (error) { - async_error = error; + WRITE_ONCE(async_error, error); dpm_save_failed_dev(dev_name(dev)); pm_dev_err(dev, state, async ? " async late" : " late", error); goto Complete; @@ -1437,7 +1676,11 @@ Skip: Complete: TRACE_SUSPEND(error); complete_all(&dev->power.completion); - return error; + + if (error || READ_ONCE(async_error)) + return; + + dpm_async_suspend_superior(dev, async_suspend_late); } static void async_suspend_late(void *data, async_cookie_t cookie) @@ -1455,7 +1698,8 @@ static void async_suspend_late(void *data, async_cookie_t cookie) int dpm_suspend_late(pm_message_t state) { ktime_t starttime = ktime_get(); - int error = 0; + struct device *dev; + int error; trace_suspend_resume(TPS("dpm_suspend_late"), state.event, true); @@ -1466,8 +1710,18 @@ int dpm_suspend_late(pm_message_t state) mutex_lock(&dpm_list_mtx); + /* + * Start processing "async" leaf devices upfront so they don't need to + * wait for the "sync" devices they don't depend on. + */ + list_for_each_entry_reverse(dev, &dpm_suspended_list, power.entry) { + dpm_clear_async_state(dev); + if (dpm_leaf_device(dev)) + dpm_async_with_cleanup(dev, async_suspend_late); + } + while (!list_empty(&dpm_suspended_list)) { - struct device *dev = to_device(dpm_suspended_list.prev); + dev = to_device(dpm_suspended_list.prev); list_move(&dev->power.entry, &dpm_late_early_list); @@ -1478,22 +1732,28 @@ int dpm_suspend_late(pm_message_t state) mutex_unlock(&dpm_list_mtx); - error = device_suspend_late(dev, state, false); + device_suspend_late(dev, state, false); put_device(dev); mutex_lock(&dpm_list_mtx); - if (error || async_error) + if (READ_ONCE(async_error)) { + dpm_async_suspend_complete_all(&dpm_suspended_list); + /* + * Move all devices to the target list to resume them + * properly. + */ + list_splice_init(&dpm_suspended_list, &dpm_late_early_list); break; + } } mutex_unlock(&dpm_list_mtx); async_synchronize_full(); - if (!error) - error = async_error; + error = READ_ONCE(async_error); if (error) { dpm_save_failed_step(SUSPEND_SUSPEND_LATE); dpm_resume_early(resume_event(state)); @@ -1574,13 +1834,15 @@ static void dpm_clear_superiors_direct_complete(struct device *dev) device_links_read_unlock(idx); } +static void async_suspend(void *data, async_cookie_t cookie); + /** * device_suspend - Execute "suspend" callbacks for given device. * @dev: Device to handle. * @state: PM transition of the system being carried out. * @async: If true, the device is being suspended asynchronously. */ -static int device_suspend(struct device *dev, pm_message_t state, bool async) +static void device_suspend(struct device *dev, pm_message_t state, bool async) { pm_callback_t callback = NULL; const char *info = NULL; @@ -1592,7 +1854,7 @@ static int device_suspend(struct device *dev, pm_message_t state, bool async) dpm_wait_for_subordinate(dev, async); - if (async_error) { + if (READ_ONCE(async_error)) { dev->power.direct_complete = false; goto Complete; } @@ -1612,7 +1874,7 @@ static int device_suspend(struct device *dev, pm_message_t state, bool async) if (pm_wakeup_pending()) { dev->power.direct_complete = false; - async_error = -EBUSY; + WRITE_ONCE(async_error, -EBUSY); goto Complete; } @@ -1628,6 +1890,7 @@ static int device_suspend(struct device *dev, pm_message_t state, bool async) pm_runtime_disable(dev); if (pm_runtime_status_suspended(dev)) { pm_dev_dbg(dev, state, "direct-complete "); + dev->power.is_suspended = true; goto Complete; } @@ -1695,14 +1958,18 @@ static int device_suspend(struct device *dev, pm_message_t state, bool async) Complete: if (error) { - async_error = error; + WRITE_ONCE(async_error, error); dpm_save_failed_dev(dev_name(dev)); pm_dev_err(dev, state, async ? " async" : "", error); } complete_all(&dev->power.completion); TRACE_SUSPEND(error); - return error; + + if (error || READ_ONCE(async_error)) + return; + + dpm_async_suspend_superior(dev, async_suspend); } static void async_suspend(void *data, async_cookie_t cookie) @@ -1720,7 +1987,8 @@ static void async_suspend(void *data, async_cookie_t cookie) int dpm_suspend(pm_message_t state) { ktime_t starttime = ktime_get(); - int error = 0; + struct device *dev; + int error; trace_suspend_resume(TPS("dpm_suspend"), state.event, true); might_sleep(); @@ -1733,8 +2001,18 @@ int dpm_suspend(pm_message_t state) mutex_lock(&dpm_list_mtx); + /* + * Start processing "async" leaf devices upfront so they don't need to + * wait for the "sync" devices they don't depend on. + */ + list_for_each_entry_reverse(dev, &dpm_prepared_list, power.entry) { + dpm_clear_async_state(dev); + if (dpm_leaf_device(dev)) + dpm_async_with_cleanup(dev, async_suspend); + } + while (!list_empty(&dpm_prepared_list)) { - struct device *dev = to_device(dpm_prepared_list.prev); + dev = to_device(dpm_prepared_list.prev); list_move(&dev->power.entry, &dpm_suspended_list); @@ -1745,22 +2023,28 @@ int dpm_suspend(pm_message_t state) mutex_unlock(&dpm_list_mtx); - error = device_suspend(dev, state, false); + device_suspend(dev, state, false); put_device(dev); mutex_lock(&dpm_list_mtx); - if (error || async_error) + if (READ_ONCE(async_error)) { + dpm_async_suspend_complete_all(&dpm_prepared_list); + /* + * Move all devices to the target list to resume them + * properly. + */ + list_splice_init(&dpm_prepared_list, &dpm_suspended_list); break; + } } mutex_unlock(&dpm_list_mtx); async_synchronize_full(); - if (!error) - error = async_error; + error = READ_ONCE(async_error); if (error) dpm_save_failed_step(SUSPEND_SUSPEND); @@ -1769,6 +2053,46 @@ int dpm_suspend(pm_message_t state) return error; } +static bool device_prepare_smart_suspend(struct device *dev) +{ + struct device_link *link; + bool ret = true; + int idx; + + /* + * The "smart suspend" feature is enabled for devices whose drivers ask + * for it and for devices without PM callbacks. + * + * However, if "smart suspend" is not enabled for the device's parent + * or any of its suppliers that take runtime PM into account, it cannot + * be enabled for the device either. + */ + if (!dev->power.no_pm_callbacks && + !dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND)) + return false; + + if (dev->parent && !dev_pm_smart_suspend(dev->parent) && + !dev->parent->power.ignore_children && !pm_runtime_blocked(dev->parent)) + return false; + + idx = device_links_read_lock(); + + list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node) { + if (!device_link_test(link, DL_FLAG_PM_RUNTIME)) + continue; + + if (!dev_pm_smart_suspend(link->supplier) && + !pm_runtime_blocked(link->supplier)) { + ret = false; + break; + } + } + + device_links_read_unlock(idx); + + return ret; +} + /** * device_prepare - Prepare a device for system power transition. * @dev: Device to handle. @@ -1780,6 +2104,7 @@ int dpm_suspend(pm_message_t state) static int device_prepare(struct device *dev, pm_message_t state) { int (*callback)(struct device *) = NULL; + bool smart_suspend; int ret = 0; /* @@ -1789,6 +2114,13 @@ static int device_prepare(struct device *dev, pm_message_t state) * it again during the complete phase. */ pm_runtime_get_noresume(dev); + /* + * If runtime PM is disabled for the device at this point and it has + * never been enabled so far, it should not be enabled until this system + * suspend-resume cycle is complete, so prepare to trigger a warning on + * subsequent attempts to enable it. + */ + smart_suspend = !pm_runtime_block_if_disabled(dev); if (dev->power.syscore) return 0; @@ -1823,6 +2155,13 @@ unlock: pm_runtime_put(dev); return ret; } + /* Do not enable "smart suspend" for devices with disabled runtime PM. */ + if (smart_suspend) + smart_suspend = device_prepare_smart_suspend(dev); + + spin_lock_irq(&dev->power.lock); + + dev->power.smart_suspend = smart_suspend; /* * A positive return value from ->prepare() means "this device appears * to be runtime-suspended and its state is fine, so if it really is @@ -1830,11 +2169,12 @@ unlock: * will do the same thing with all of its descendants". This only * applies to suspend transitions, however. */ - spin_lock_irq(&dev->power.lock); dev->power.direct_complete = state.event == PM_EVENT_SUSPEND && (ret > 0 || dev->power.no_pm_callbacks) && !dev_pm_test_driver_flags(dev, DPM_FLAG_NO_DIRECT_COMPLETE); + spin_unlock_irq(&dev->power.lock); + return 0; } @@ -1849,7 +2189,6 @@ int dpm_prepare(pm_message_t state) int error = 0; trace_suspend_resume(TPS("dpm_prepare"), state.event, true); - might_sleep(); /* * Give a chance for the known devices to complete their probes, before @@ -1916,8 +2255,10 @@ int dpm_suspend_start(pm_message_t state) error = dpm_prepare(state); if (error) dpm_save_failed_step(SUSPEND_PREPARE); - else + else { + pm_restrict_gfp_mask(); error = dpm_suspend(state); + } dpm_show_time(starttime, state, error, "start"); return error; @@ -1998,6 +2339,5 @@ void device_pm_check_callbacks(struct device *dev) bool dev_pm_skip_suspend(struct device *dev) { - return dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) && - pm_runtime_status_suspended(dev); + return dev_pm_smart_suspend(dev) && pm_runtime_status_suspended(dev); } |