From: Guangyu Sun <guangyu.sun@oracle.com>
Date: Thu, 4 Oct 2012 22:46:56 +0000 (-0700)
Subject: Revert "hrtimer: Update hrtimer base offsets each hrtimer_interrupt"
X-Git-Tag: v2.6.39-400.9.0~303^2~24
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=bdb1ba44f570c9729afbae92225f525fb6ea1a51;p=users%2Fjedix%2Flinux-maple.git

Revert "hrtimer: Update hrtimer base offsets each hrtimer_interrupt"

This reverts commit e5f24110402047b80191e280ba54cf0c6d346f7c.

Signed-off-by: Guangyu Sun <guangyu.sun@oracle.com>
---

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 957869fd596a6..8fc65334191e8 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -657,14 +657,6 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
 	return 0;
 }
 
-static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base)
-{
-	ktime_t *offs_real = &base->clock_base[HRTIMER_BASE_REALTIME].offset;
-	ktime_t *offs_boot = &base->clock_base[HRTIMER_BASE_BOOTTIME].offset;
-
-	return ktime_get_update_offsets(offs_real, offs_boot);
-}
-
 /*
  * Retrigger next event is called after clock was set
  *
@@ -673,12 +665,22 @@ static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base)
 static void retrigger_next_event(void *arg)
 {
 	struct hrtimer_cpu_base *base = &__get_cpu_var(hrtimer_bases);
+	struct timespec realtime_offset, xtim, wtm, sleep;
 
 	if (!hrtimer_hres_active())
 		return;
 
+	/* Optimized out for !HIGH_RES */
+	get_xtime_and_monotonic_and_sleep_offset(&xtim, &wtm, &sleep);
+	set_normalized_timespec(&realtime_offset, -wtm.tv_sec, -wtm.tv_nsec);
+
+	/* Adjust CLOCK_REALTIME offset */
 	raw_spin_lock(&base->lock);
-	hrtimer_update_base(base);
+	base->clock_base[HRTIMER_BASE_REALTIME].offset =
+		timespec_to_ktime(realtime_offset);
+	base->clock_base[HRTIMER_BASE_BOOTTIME].offset =
+		timespec_to_ktime(sleep);
+
 	hrtimer_force_reprogram(base, 0);
 	raw_spin_unlock(&base->lock);
 }
@@ -708,6 +710,7 @@ static int hrtimer_switch_to_hres(void)
 		base->clock_base[i].resolution = KTIME_HIGH_RES;
 
 	tick_setup_sched_timer();
+
 	/* "Retrigger" the interrupt to get things going */
 	retrigger_next_event(NULL);
 	local_irq_restore(flags);
@@ -1261,7 +1264,7 @@ void hrtimer_interrupt(struct clock_event_device *dev)
 	dev->next_event.tv64 = KTIME_MAX;
 
 	raw_spin_lock(&cpu_base->lock);
-	entry_time = now = hrtimer_update_base(cpu_base);
+	entry_time = now = ktime_get();
 retry:
 	expires_next.tv64 = KTIME_MAX;
 	/*
@@ -1339,12 +1342,9 @@ retry:
 	 * We need to prevent that we loop forever in the hrtimer
 	 * interrupt routine. We give it 3 attempts to avoid
 	 * overreacting on some spurious event.
-	 *
-	 * Acquire base lock for updating the offsets and retrieving
-	 * the current time.
 	 */
 	raw_spin_lock(&cpu_base->lock);
-	now = hrtimer_update_base(cpu_base);
+	now = ktime_get();
 	cpu_base->nr_retries++;
 	if (++retries < 3)
 		goto retry;