1 files changed, 10 insertions, 35 deletions

diff --git a/arch/um/kernel/time.c b/arch/um/kernel/time.c
index 3cb7135e5c47..2acdc7efb2ac 100644
--- a/arch/um/kernel/time.c
+++ b/arch/um/kernel/time.c
@@ -20,41 +20,12 @@ unsigned long long sched_clock(void)
 	return (unsigned long long)jiffies_64 * (1000000000 / HZ);
 }
 
-#ifdef CONFIG_UML_REAL_TIME_CLOCK
-static unsigned long long prev_nsecs[NR_CPUS];
-static long long delta[NR_CPUS];		/* Deviation per interval */
-#endif
-
 void timer_handler(int sig, struct uml_pt_regs *regs)
 {
-	unsigned long long ticks = 0;
 	unsigned long flags;
-#ifdef CONFIG_UML_REAL_TIME_CLOCK
-	int c = cpu();
-	if (prev_nsecs[c]) {
-		/* We've had 1 tick */
-		unsigned long long nsecs = os_nsecs();
-
-		delta[c] += nsecs - prev_nsecs[c];
-		prev_nsecs[c] = nsecs;
-
-		/* Protect against the host clock being set backwards */
-		if (delta[c] < 0)
-			delta[c] = 0;
-
-		ticks += (delta[c] * HZ) / BILLION;
-		delta[c] -= (ticks * BILLION) / HZ;
-	}
-	else prev_nsecs[c] = os_nsecs();
-#else
-	ticks = 1;
-#endif
 
 	local_irq_save(flags);
-	while (ticks > 0) {
-		do_IRQ(TIMER_IRQ, regs);
-		ticks--;
-	}
+	do_IRQ(TIMER_IRQ, regs);
 	local_irq_restore(flags);
 }
 
@@ -68,10 +39,8 @@ static void itimer_set_mode(enum clock_event_mode mode,
 
 	case CLOCK_EVT_MODE_SHUTDOWN:
 	case CLOCK_EVT_MODE_UNUSED:
-		disable_timer();
-		break;
 	case CLOCK_EVT_MODE_ONESHOT:
-		BUG();
+		disable_timer();
 		break;
 
 	case CLOCK_EVT_MODE_RESUME:
@@ -79,13 +48,19 @@ static void itimer_set_mode(enum clock_event_mode mode,
 	}
 }
 
+static int itimer_next_event(unsigned long delta,
+			     struct clock_event_device *evt)
+{
+	return timer_one_shot(delta + 1);
+}
+
 static struct clock_event_device itimer_clockevent = {
 	.name		= "itimer",
 	.rating		= 250,
 	.cpumask	= CPU_MASK_ALL,
-	.features	= CLOCK_EVT_FEAT_PERIODIC,
+	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
 	.set_mode	= itimer_set_mode,
-	.set_next_event = NULL,
+	.set_next_event = itimer_next_event,
 	.shift		= 32,
 	.irq		= 0,
 };