Merge tag 'for-v4.6-rc/omap-fixes-a' of git://git.kernel.org/pub/scm/linux/kernel/git/pjw/omap-pending into omap-for-v4.6/fixes

ARM: OMAP2+: first hwmod fix for v4.6-rc

Fix a longstanding bug in the hwmod code that could cause
hardware SYSCONFIG register values to not match the kernel's
idea of what they should be, and that could result in lower
performance during IP block idle entry.

Basic build, boot, and PM test logs are available here:

http://www.pwsan.com/omap/testlogs/omap-hwmod-fixes-a-for-v4.6-rc/20160326231727/

1 files changed, 13 insertions, 8 deletions

diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index e0f90c2b57aa..d234022805dc 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -185,10 +185,12 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout)
 	rcu_read_unlock();
 }
 
-static unsigned long timeout_jiffies(unsigned long timeout)
+static long hung_timeout_jiffies(unsigned long last_checked,
+				 unsigned long timeout)
 {
 	/* timeout of 0 will disable the watchdog */
-	return timeout ? timeout * HZ : MAX_SCHEDULE_TIMEOUT;
+	return timeout ? last_checked - jiffies + timeout * HZ :
+		MAX_SCHEDULE_TIMEOUT;
 }
 
 /*
@@ -224,18 +226,21 @@ EXPORT_SYMBOL_GPL(reset_hung_task_detector);
  */
 static int watchdog(void *dummy)
 {
+	unsigned long hung_last_checked = jiffies;
+
 	set_user_nice(current, 0);
 
 	for ( ; ; ) {
 		unsigned long timeout = sysctl_hung_task_timeout_secs;
+		long t = hung_timeout_jiffies(hung_last_checked, timeout);
 
-		while (schedule_timeout_interruptible(timeout_jiffies(timeout)))
-			timeout = sysctl_hung_task_timeout_secs;
-
-		if (atomic_xchg(&reset_hung_task, 0))
+		if (t <= 0) {
+			if (!atomic_xchg(&reset_hung_task, 0))
+				check_hung_uninterruptible_tasks(timeout);
+			hung_last_checked = jiffies;
 			continue;
-
-		check_hung_uninterruptible_tasks(timeout);
+		}
+		schedule_timeout_interruptible(t);
 	}
 
 	return 0;