power: increment wakeup_count when save_wakeup_count failed.

user-space aborts suspend attempt if writing wakeup_count failed.
Count the write failure towards wakeup_count.

Signed-off-by: jinqian <jinqian@google.com>
Change-Id: Ic0123ac7ef31564700b1f6b5f2234275ac104244

diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c
index 6686e5ff6041474e118c3e15a11bad0ab2690e9a..ebe6c7310c85875d410ec59d79741b203c14dc92 100644 (file)
--- a/drivers/base/power/wakeup.c
+++ b/drivers/base/power/wakeup.c
@@ -54,6 +54,8 @@ static LIST_HEAD(wakeup_sources);
 
 static DECLARE_WAIT_QUEUE_HEAD(wakeup_count_wait_queue);
 
+static ktime_t last_read_time;
+
 /**
  * wakeup_source_prepare - Prepare a new wakeup source for initialization.
  * @ws: Wakeup source to prepare.
@@ -778,10 +780,15 @@ bool pm_wakeup_pending(void)
 bool pm_get_wakeup_count(unsigned int *count, bool block)
 {
        unsigned int cnt, inpr;
+       unsigned long flags;
 
        if (block) {
                DEFINE_WAIT(wait);
 
+               spin_lock_irqsave(&events_lock, flags);
+               last_read_time = ktime_get();
+               spin_unlock_irqrestore(&events_lock, flags);
+
                for (;;) {
                        prepare_to_wait(&wakeup_count_wait_queue, &wait,
                                        TASK_INTERRUPTIBLE);
@@ -813,6 +820,7 @@ bool pm_save_wakeup_count(unsigned int count)
 {
        unsigned int cnt, inpr;
        unsigned long flags;
+       struct wakeup_source *ws;
 
        events_check_enabled = false;
        spin_lock_irqsave(&events_lock, flags);
@@ -820,6 +828,15 @@ bool pm_save_wakeup_count(unsigned int count)
        if (cnt == count && inpr == 0) {
                saved_count = count;
                events_check_enabled = true;
+       } else {
+               rcu_read_lock();
+               list_for_each_entry_rcu(ws, &wakeup_sources, entry) {
+                       if (ws->active ||
+                           ktime_compare(ws->last_time, last_read_time) > 0) {
+                               ws->wakeup_count++;
+                       }
+               }
+               rcu_read_unlock();
        }
        spin_unlock_irqrestore(&events_lock, flags);
        return events_check_enabled;