diff mbox

[update] Re: [PATCH] PM: Make it possible to avoid wakeup events from being lost

Message ID 201007010152.03869.rjw@sisk.pl (mailing list archive)
State Not Applicable, archived
Headers show

Commit Message

Rafael Wysocki June 30, 2010, 11:52 p.m. UTC
None
diff mbox

Patch

Index: linux-2.6/drivers/base/power/wakeup.c
===================================================================
--- linux-2.6.orig/drivers/base/power/wakeup.c
+++ linux-2.6/drivers/base/power/wakeup.c
@@ -9,6 +9,7 @@ 
 #include <linux/device.h>
 #include <linux/slab.h>
 #include <linux/sched.h>
+#include <linux/ktime.h>
 #include <linux/capability.h>
 #include <linux/suspend.h>
 #include <linux/pm.h>
@@ -28,6 +29,12 @@  static unsigned long events_in_progress;
 
 static DEFINE_SPINLOCK(events_lock);
 
+static void pm_wakeup_timer_fn(unsigned long data);
+
+static DEFINE_TIMER(events_timer, pm_wakeup_timer_fn, 0, 0);
+static unsigned long events_timer_expires;
+static unsigned long delayed_count;
+
 /*
  * The functions below use the observation that each wakeup event starts a
  * period in which the system should not be suspended.  The moment this period
@@ -103,17 +110,23 @@  void pm_relax(void)
 }
 
 /**
- * pm_wakeup_work_fn - Deferred closing of a wakeup event.
+ * pm_wakeup_timer_fn - Deferred closing of a wakeup event.
  *
  * Execute pm_relax() for a wakeup event detected in the past and free the
  * work item object used for queuing up the work.
  */
-static void pm_wakeup_work_fn(struct work_struct *work)
+static void pm_wakeup_timer_fn(unsigned long data)
 {
-	struct delayed_work *dwork = to_delayed_work(work);
+	unsigned long flags;
 
-	pm_relax();
-	kfree(dwork);
+	spin_lock_irqsave(&events_lock, flags);
+	if (events_timer_expires && time_after(jiffies, events_timer_expires)) {
+		events_in_progress -= delayed_count;
+		event_count += delayed_count;
+		delayed_count = 0;
+		events_timer_expires = 0;
+	}
+	spin_unlock_irqrestore(&events_lock, flags);
 }
 
 /**
@@ -132,19 +145,31 @@  static void pm_wakeup_work_fn(struct wor
 void pm_wakeup_event(struct device *dev, unsigned int msec)
 {
 	unsigned long flags;
-	struct delayed_work *dwork;
-
-	dwork = msec ? kzalloc(sizeof(*dwork), GFP_ATOMIC) : NULL;
 
 	spin_lock_irqsave(&events_lock, flags);
 	if (dev)
 		dev->power.wakeup_count++;
 
-	if (dwork) {
-		INIT_DELAYED_WORK(dwork, pm_wakeup_work_fn);
-		schedule_delayed_work(dwork, msecs_to_jiffies(msec));
+	if (msec) {
+		ktime_t kt;
+		struct timespec ts;
+		unsigned long expires;
+
+		kt = ktime_get();
+		kt = ktime_add_ns(kt, msec * NSEC_PER_MSEC);
+		ts = ktime_to_timespec(kt);
+		expires = timespec_to_jiffies(&ts);
+		if (!expires)
+			expires = 1;
+
+		if (!events_timer_expires
+		    || time_after(expires, events_timer_expires)) {
+			mod_timer(&events_timer, expires);
+			events_timer_expires = expires;
+		}
 
 		events_in_progress++;
+		delayed_count++;
 	} else {
 		event_count++;
 	}