Merge branch 'pm-sleep'

* pm-sleep:
  PM / Sleep: User space wakeup sources garbage collector Kconfig option
  PM / Sleep: Make the limit of user space wakeup sources configurable
  PM / Documentation: suspend-and-cpuhotplug.txt: Fix typo
  PM / Sleep: Fix a mistake in a conditional in autosleep_store()
  epoll: Add a flag, EPOLLWAKEUP, to prevent suspend while epoll events are ready
  PM / Sleep: Add user space interface for manipulating wakeup sources, v3
  PM / Sleep: Add "prevent autosleep time" statistics to wakeup sources
  PM / Sleep: Implement opportunistic sleep, v2
  PM / Sleep: Add wakeup_source_activate and wakeup_source_deactivate tracepoints
  PM / Sleep: Change wakeup source statistics to follow Android
  PM / Sleep: Use wait queue to signal "no wakeup events in progress"
  PM / Sleep: Look for wakeup events in later stages of device suspend
  PM / Hibernate: Hibernate/thaw fixes/improvements

3 files changed, 179 insertions, 59 deletions

diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index b462c0e341cb..e0fb5b0435a3 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -889,6 +889,11 @@ static int dpm_suspend_noirq(pm_message_t state)
                 if (!list_empty(&dev->power.entry))
                         list_move(&dev->power.entry, &dpm_noirq_list);
                 put_device(dev);
+
+                if (pm_wakeup_pending()) {
+                        error = -EBUSY;
+                        break;
+                }
         }
         mutex_unlock(&dpm_list_mtx);
         if (error)
@@ -962,6 +967,11 @@ static int dpm_suspend_late(pm_message_t state)
                 if (!list_empty(&dev->power.entry))
                         list_move(&dev->power.entry, &dpm_late_early_list);
                 put_device(dev);
+
+                if (pm_wakeup_pending()) {
+                        error = -EBUSY;
+                        break;
+                }
         }
         mutex_unlock(&dpm_list_mtx);
         if (error)
diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c
index 95c12f6cb5b9..48be2ad4dd2c 100644
--- a/drivers/base/power/sysfs.c
+++ b/drivers/base/power/sysfs.c
@@ -314,22 +314,41 @@ static ssize_t wakeup_active_count_show(struct device *dev,
 
 static DEVICE_ATTR(wakeup_active_count, 0444, wakeup_active_count_show, NULL);
 
-static ssize_t wakeup_hit_count_show(struct device *dev,
-                                struct device_attribute *attr, char *buf)
+static ssize_t wakeup_abort_count_show(struct device *dev,
+                                        struct device_attribute *attr,
+                                        char *buf)
+{
+        unsigned long count = 0;
+        bool enabled = false;
+
+        spin_lock_irq(&dev->power.lock);
+        if (dev->power.wakeup) {
+                count = dev->power.wakeup->wakeup_count;
+                enabled = true;
+        }
+        spin_unlock_irq(&dev->power.lock);
+        return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
+}
+
+static DEVICE_ATTR(wakeup_abort_count, 0444, wakeup_abort_count_show, NULL);
+
+static ssize_t wakeup_expire_count_show(struct device *dev,
+                                        struct device_attribute *attr,
+                                        char *buf)
 {
         unsigned long count = 0;
         bool enabled = false;
 
         spin_lock_irq(&dev->power.lock);
         if (dev->power.wakeup) {
-                count = dev->power.wakeup->hit_count;
+                count = dev->power.wakeup->expire_count;
                 enabled = true;
         }
         spin_unlock_irq(&dev->power.lock);
         return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
 }
 
-static DEVICE_ATTR(wakeup_hit_count, 0444, wakeup_hit_count_show, NULL);
+static DEVICE_ATTR(wakeup_expire_count, 0444, wakeup_expire_count_show, NULL);
 
 static ssize_t wakeup_active_show(struct device *dev,
                                 struct device_attribute *attr, char *buf)
@@ -398,6 +417,27 @@ static ssize_t wakeup_last_time_show(struct device *dev,
 }
 
 static DEVICE_ATTR(wakeup_last_time_ms, 0444, wakeup_last_time_show, NULL);
+
+#ifdef CONFIG_PM_AUTOSLEEP
+static ssize_t wakeup_prevent_sleep_time_show(struct device *dev,
+                                              struct device_attribute *attr,
+                                              char *buf)
+{
+        s64 msec = 0;
+        bool enabled = false;
+
+        spin_lock_irq(&dev->power.lock);
+        if (dev->power.wakeup) {
+                msec = ktime_to_ms(dev->power.wakeup->prevent_sleep_time);
+                enabled = true;
+        }
+        spin_unlock_irq(&dev->power.lock);
+        return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
+}
+
+static DEVICE_ATTR(wakeup_prevent_sleep_time_ms, 0444,
+                   wakeup_prevent_sleep_time_show, NULL);
+#endif /* CONFIG_PM_AUTOSLEEP */
 #endif /* CONFIG_PM_SLEEP */
 
 #ifdef CONFIG_PM_ADVANCED_DEBUG
@@ -486,11 +526,15 @@ static struct attribute *wakeup_attrs[] = {
         &dev_attr_wakeup.attr,
         &dev_attr_wakeup_count.attr,
         &dev_attr_wakeup_active_count.attr,
-        &dev_attr_wakeup_hit_count.attr,
+        &dev_attr_wakeup_abort_count.attr,
+        &dev_attr_wakeup_expire_count.attr,
         &dev_attr_wakeup_active.attr,
         &dev_attr_wakeup_total_time_ms.attr,
         &dev_attr_wakeup_max_time_ms.attr,
         &dev_attr_wakeup_last_time_ms.attr,
+#ifdef CONFIG_PM_AUTOSLEEP
+        &dev_attr_wakeup_prevent_sleep_time_ms.attr,
+#endif
 #endif
         NULL,
 };
diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c
index 2a3e581b8dcd..cbb463b3a750 100644
--- a/drivers/base/power/wakeup.c
+++ b/drivers/base/power/wakeup.c
@@ -14,16 +14,15 @@
 #include <linux/suspend.h>
 #include <linux/seq_file.h>
 #include <linux/debugfs.h>
+#include <trace/events/power.h>
 
 #include "power.h"
 
-#define TIMEOUT         100
-
 /*
  * If set, the suspend/hibernate code will abort transitions to a sleep state
  * if wakeup events are registered during or immediately before the transition.
  */
-bool events_check_enabled;
+bool events_check_enabled __read_mostly;
 
 /*
  * Combined counters of registered wakeup events and wakeup events in progress.
@@ -52,6 +51,8 @@ static void pm_wakeup_timer_fn(unsigned long data);
 
 static LIST_HEAD(wakeup_sources);
 
+static DECLARE_WAIT_QUEUE_HEAD(wakeup_count_wait_queue);
+
 /**
  * wakeup_source_prepare - Prepare a new wakeup source for initialization.
  * @ws: Wakeup source to prepare.
@@ -132,6 +133,7 @@ void wakeup_source_add(struct wakeup_source *ws)
         spin_lock_init(&ws->lock);
         setup_timer(&ws->timer, pm_wakeup_timer_fn, (unsigned long)ws);
         ws->active = false;
+        ws->last_time = ktime_get();
 
         spin_lock_irq(&events_lock);
         list_add_rcu(&ws->entry, &wakeup_sources);
@@ -374,12 +376,33 @@ EXPORT_SYMBOL_GPL(device_set_wakeup_enable);
  */
 static void wakeup_source_activate(struct wakeup_source *ws)
 {
+        unsigned int cec;
+
         ws->active = true;
         ws->active_count++;
         ws->last_time = ktime_get();
+        if (ws->autosleep_enabled)
+                ws->start_prevent_time = ws->last_time;
 
         /* Increment the counter of events in progress. */
-        atomic_inc(&combined_event_count);
+        cec = atomic_inc_return(&combined_event_count);
+
+        trace_wakeup_source_activate(ws->name, cec);
+}
+
+/**
+ * wakeup_source_report_event - Report wakeup event using the given source.
+ * @ws: Wakeup source to report the event for.
+ */
+static void wakeup_source_report_event(struct wakeup_source *ws)
+{
+        ws->event_count++;
+        /* This is racy, but the counter is approximate anyway. */
+        if (events_check_enabled)
+                ws->wakeup_count++;
+
+        if (!ws->active)
+                wakeup_source_activate(ws);
 }
 
 /**
@@ -397,10 +420,7 @@ void __pm_stay_awake(struct wakeup_source *ws)
 
         spin_lock_irqsave(&ws->lock, flags);
 
-        ws->event_count++;
-        if (!ws->active)
-                wakeup_source_activate(ws);
-
+        wakeup_source_report_event(ws);
         del_timer(&ws->timer);
         ws->timer_expires = 0;
 
@@ -432,6 +452,17 @@ void pm_stay_awake(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(pm_stay_awake);
 
+#ifdef CONFIG_PM_AUTOSLEEP
+static void update_prevent_sleep_time(struct wakeup_source *ws, ktime_t now)
+{
+        ktime_t delta = ktime_sub(now, ws->start_prevent_time);
+        ws->prevent_sleep_time = ktime_add(ws->prevent_sleep_time, delta);
+}
+#else
+static inline void update_prevent_sleep_time(struct wakeup_source *ws,
+                                             ktime_t now) {}
+#endif
+
 /**
  * wakup_source_deactivate - Mark given wakeup source as inactive.
  * @ws: Wakeup source to handle.
@@ -442,6 +473,7 @@ EXPORT_SYMBOL_GPL(pm_stay_awake);
  */
 static void wakeup_source_deactivate(struct wakeup_source *ws)
 {
+        unsigned int cnt, inpr, cec;
         ktime_t duration;
         ktime_t now;
 
@@ -468,14 +500,23 @@ static void wakeup_source_deactivate(struct wakeup_source *ws)
         if (ktime_to_ns(duration) > ktime_to_ns(ws->max_time))
                 ws->max_time = duration;
 
+        ws->last_time = now;
         del_timer(&ws->timer);
         ws->timer_expires = 0;
 
+        if (ws->autosleep_enabled)
+                update_prevent_sleep_time(ws, now);
+
         /*
          * Increment the counter of registered wakeup events and decrement the
          * couter of wakeup events in progress simultaneously.
          */
-        atomic_add(MAX_IN_PROGRESS, &combined_event_count);
+        cec = atomic_add_return(MAX_IN_PROGRESS, &combined_event_count);
+        trace_wakeup_source_deactivate(ws->name, cec);
+
+        split_counters(&cnt, &inpr);
+        if (!inpr && waitqueue_active(&wakeup_count_wait_queue))
+                wake_up(&wakeup_count_wait_queue);
 }
 
 /**
@@ -536,8 +577,10 @@ static void pm_wakeup_timer_fn(unsigned long data)
         spin_lock_irqsave(&ws->lock, flags);
 
         if (ws->active && ws->timer_expires
-            && time_after_eq(jiffies, ws->timer_expires))
+            && time_after_eq(jiffies, ws->timer_expires)) {
                 wakeup_source_deactivate(ws);
+                ws->expire_count++;
+        }
 
         spin_unlock_irqrestore(&ws->lock, flags);
 }
@@ -564,9 +607,7 @@ void __pm_wakeup_event(struct wakeup_source *ws, unsigned int msec)
 
         spin_lock_irqsave(&ws->lock, flags);
 
-        ws->event_count++;
-        if (!ws->active)
-                wakeup_source_activate(ws);
+        wakeup_source_report_event(ws);
 
         if (!msec) {
                 wakeup_source_deactivate(ws);
@@ -609,24 +650,6 @@ void pm_wakeup_event(struct device *dev, unsigned int msec)
 EXPORT_SYMBOL_GPL(pm_wakeup_event);
 
 /**
- * pm_wakeup_update_hit_counts - Update hit counts of all active wakeup sources.
- */
-static void pm_wakeup_update_hit_counts(void)
-{
-        unsigned long flags;
-        struct wakeup_source *ws;
-
-        rcu_read_lock();
-        list_for_each_entry_rcu(ws, &wakeup_sources, entry) {
-                spin_lock_irqsave(&ws->lock, flags);
-                if (ws->active)
-                        ws->hit_count++;
-                spin_unlock_irqrestore(&ws->lock, flags);
-        }
-        rcu_read_unlock();
-}
-
-/**
  * pm_wakeup_pending - Check if power transition in progress should be aborted.
  *
  * Compare the current number of registered wakeup events with its preserved
@@ -648,32 +671,38 @@ bool pm_wakeup_pending(void)
                 events_check_enabled = !ret;
         }
         spin_unlock_irqrestore(&events_lock, flags);
-        if (ret)
-                pm_wakeup_update_hit_counts();
         return ret;
 }
 
 /**
  * pm_get_wakeup_count - Read the number of registered wakeup events.
  * @count: Address to store the value at.
+ * @block: Whether or not to block.
  *
- * Store the number of registered wakeup events at the address in @count.  Block
- * if the current number of wakeup events being processed is nonzero.
+ * Store the number of registered wakeup events at the address in @count.  If
+ * @block is set, block until the current number of wakeup events being
+ * processed is zero.
  *
- * Return 'false' if the wait for the number of wakeup events being processed to
- * drop down to zero has been interrupted by a signal (and the current number
- * of wakeup events being processed is still nonzero).  Otherwise return 'true'.
+ * Return 'false' if the current number of wakeup events being processed is
+ * nonzero.  Otherwise return 'true'.
  */
-bool pm_get_wakeup_count(unsigned int *count)
+bool pm_get_wakeup_count(unsigned int *count, bool block)
 {
         unsigned int cnt, inpr;
 
-        for (;;) {
-                split_counters(&cnt, &inpr);
-                if (inpr == 0 || signal_pending(current))
-                        break;
-                pm_wakeup_update_hit_counts();
-                schedule_timeout_interruptible(msecs_to_jiffies(TIMEOUT));
+        if (block) {
+                DEFINE_WAIT(wait);
+
+                for (;;) {
+                        prepare_to_wait(&wakeup_count_wait_queue, &wait,
+                                        TASK_INTERRUPTIBLE);
+                        split_counters(&cnt, &inpr);
+                        if (inpr == 0 || signal_pending(current))
+                                break;
+
+                        schedule();
+                }
+                finish_wait(&wakeup_count_wait_queue, &wait);
         }
 
         split_counters(&cnt, &inpr);
@@ -703,11 +732,37 @@ bool pm_save_wakeup_count(unsigned int count)
                 events_check_enabled = true;
         }
         spin_unlock_irq(&events_lock);
-        if (!events_check_enabled)
-                pm_wakeup_update_hit_counts();
         return events_check_enabled;
 }
 
+#ifdef CONFIG_PM_AUTOSLEEP
+/**
+ * pm_wakep_autosleep_enabled - Modify autosleep_enabled for all wakeup sources.
+ * @enabled: Whether to set or to clear the autosleep_enabled flags.
+ */
+void pm_wakep_autosleep_enabled(bool set)
+{
+        struct wakeup_source *ws;
+        ktime_t now = ktime_get();
+
+        rcu_read_lock();
+        list_for_each_entry_rcu(ws, &wakeup_sources, entry) {
+                spin_lock_irq(&ws->lock);
+                if (ws->autosleep_enabled != set) {
+                        ws->autosleep_enabled = set;
+                        if (ws->active) {
+                                if (set)
+                                        ws->start_prevent_time = now;
+                                else
+                                        update_prevent_sleep_time(ws, now);
+                        }
+                }
+                spin_unlock_irq(&ws->lock);
+        }
+        rcu_read_unlock();
+}
+#endif /* CONFIG_PM_AUTOSLEEP */
+
 static struct dentry *wakeup_sources_stats_dentry;
 
 /**
@@ -723,27 +778,37 @@ static int print_wakeup_source_stats(struct seq_file *m,
         ktime_t max_time;
         unsigned long active_count;
         ktime_t active_time;
+        ktime_t prevent_sleep_time;
         int ret;
 
         spin_lock_irqsave(&ws->lock, flags);
 
         total_time = ws->total_time;
         max_time = ws->max_time;
+        prevent_sleep_time = ws->prevent_sleep_time;
         active_count = ws->active_count;
         if (ws->active) {
-                active_time = ktime_sub(ktime_get(), ws->last_time);
+                ktime_t now = ktime_get();
+
+                active_time = ktime_sub(now, ws->last_time);
                 total_time = ktime_add(total_time, active_time);
                 if (active_time.tv64 > max_time.tv64)
                         max_time = active_time;
+
+                if (ws->autosleep_enabled)
+                        prevent_sleep_time = ktime_add(prevent_sleep_time,
+                                ktime_sub(now, ws->start_prevent_time));
         } else {
                 active_time = ktime_set(0, 0);
         }
 
-        ret = seq_printf(m, "%-12s\t%lu\t\t%lu\t\t%lu\t\t"
-                        "%lld\t\t%lld\t\t%lld\t\t%lld\n",
-                        ws->name, active_count, ws->event_count, ws->hit_count,
+        ret = seq_printf(m, "%-12s\t%lu\t\t%lu\t\t%lu\t\t%lu\t\t"
+                        "%lld\t\t%lld\t\t%lld\t\t%lld\t\t%lld\n",
+                        ws->name, active_count, ws->event_count,
+                        ws->wakeup_count, ws->expire_count,
                         ktime_to_ms(active_time), ktime_to_ms(total_time),
-                        ktime_to_ms(max_time), ktime_to_ms(ws->last_time));
+                        ktime_to_ms(max_time), ktime_to_ms(ws->last_time),
+                        ktime_to_ms(prevent_sleep_time));
 
         spin_unlock_irqrestore(&ws->lock, flags);
 
@@ -758,8 +823,9 @@ static int wakeup_sources_stats_show(struct seq_file *m, void *unused)
 {
         struct wakeup_source *ws;
 
-        seq_puts(m, "name\t\tactive_count\tevent_count\thit_count\t"
-                "active_since\ttotal_time\tmax_time\tlast_change\n");
+        seq_puts(m, "name\t\tactive_count\tevent_count\twakeup_count\t"
+                "expire_count\tactive_since\ttotal_time\tmax_time\t"
+                "last_change\tprevent_suspend_time\n");
 
         rcu_read_lock();
         list_for_each_entry_rcu(ws, &wakeup_sources, entry)