softirq-per-cpu-assumptions-fixes.patch

From acc91991542212f243d7e8293530aa224a98f77f Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Fri, 3 Jul 2009 08:44:01 -0500
Subject: [PATCH] softirq: per cpu assumptions fixes

commit 33fe41da821c6c542bcaa612a46695425525fdc6 in tip.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index c586357..82efa41 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -499,9 +499,9 @@ static inline int hrtimer_is_hres_enabled(void)
 /*
  * Is the high resolution mode active ?
  */
-static inline int hrtimer_hres_active(void)
+static inline int hrtimer_hres_active(struct hrtimer_cpu_base *cpu_base)
 {
-	return __get_cpu_var(hrtimer_bases).hres_active;
+	return cpu_base->hres_active;
 }
 
 /*
@@ -611,11 +611,11 @@ static int hrtimer_reprogram(struct hrtimer *timer,
  */
 static void retrigger_next_event(void *arg)
 {
-	struct hrtimer_cpu_base *base;
+	struct hrtimer_cpu_base *base = &__get_cpu_var(hrtimer_bases);
 	struct timespec realtime_offset;
 	unsigned long seq;
 
-	if (!hrtimer_hres_active())
+	if (!hrtimer_hres_active(base))
 		return;
 
 	do {
@@ -625,8 +625,6 @@ static void retrigger_next_event(void *arg)
 					-wall_to_monotonic.tv_nsec);
 	} while (read_raw_seqretry(&xtime_lock, seq));
 
-	base = &__get_cpu_var(hrtimer_bases);
-
 	/* Adjust CLOCK_REALTIME offset */
 	raw_spin_lock(&base->lock);
 	base->clock_base[CLOCK_REALTIME].offset =
@@ -709,10 +707,8 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
 /*
  * Switch to high resolution mode
  */
-static int hrtimer_switch_to_hres(void)
+static int hrtimer_switch_to_hres(struct hrtimer_cpu_base *base)
 {
-	int cpu = smp_processor_id();
-	struct hrtimer_cpu_base *base = &per_cpu(hrtimer_bases, cpu);
 	unsigned long flags;
 
 	if (base->hres_active)
@@ -723,7 +719,7 @@ static int hrtimer_switch_to_hres(void)
 	if (tick_init_highres()) {
 		local_irq_restore(flags);
 		printk(KERN_WARNING "Could not switch to high resolution "
-				    "mode on CPU %d\n", cpu);
+		       "mode on CPU %d\n", raw_smp_processor_id());
 		return 0;
 	}
 	base->hres_active = 1;
@@ -740,9 +736,15 @@ static int hrtimer_switch_to_hres(void)
 
 #else
 
-static inline int hrtimer_hres_active(void) { return 0; }
+static inline int hrtimer_hres_active(struct hrtimer_cpu_base *base)
+{
+	return 0;
+}
 static inline int hrtimer_is_hres_enabled(void) { return 0; }
-static inline int hrtimer_switch_to_hres(void) { return 0; }
+static inline int hrtimer_switch_to_hres(struct hrtimer_cpu_base *base)
+{
+	return 0;
+}
 static inline void
 hrtimer_force_reprogram(struct hrtimer_cpu_base *base, int skip_equal) { }
 static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
@@ -940,7 +942,7 @@ static void __remove_hrtimer(struct hrtimer *timer,
 		base->first = rb_next(&timer->node);
 #ifdef CONFIG_HIGH_RES_TIMERS
 		/* Reprogram the clock event device. if enabled */
-		if (reprogram && hrtimer_hres_active()) {
+		if (reprogram && hrtimer_hres_active(base->cpu_base)) {
 			ktime_t expires;
 
 			expires = ktime_sub(hrtimer_get_expires(timer),
@@ -1153,7 +1155,7 @@ ktime_t hrtimer_get_next_event(void)
 
 	raw_spin_lock_irqsave(&cpu_base->lock, flags);
 
-	if (!hrtimer_hres_active()) {
+	if (!hrtimer_hres_active(cpu_base)) {
 		for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++, base++) {
 			struct hrtimer *timer;
 
@@ -1398,9 +1400,11 @@ retry:
  */
 static void __hrtimer_peek_ahead_timers(void)
 {
+	struct hrtimer_cpu_base *cpu_base;
 	struct tick_device *td;
 
-	if (!hrtimer_hres_active())
+	cpu_base = &__get_cpu_var(hrtimer_bases);
+	if (!hrtimer_hres_active(cpu_base))
 		return;
 
 	td = &__get_cpu_var(tick_cpu_device);
@@ -1446,7 +1450,9 @@ static inline void __hrtimer_peek_ahead_timers(void) { }
  */
 void hrtimer_run_pending(void)
 {
-	if (hrtimer_hres_active())
+	struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases);
+
+	if (hrtimer_hres_active(cpu_base))
 		return;
 
 	/*
@@ -1458,7 +1464,7 @@ void hrtimer_run_pending(void)
 	 * deadlock vs. xtime_lock.
 	 */
 	if (tick_check_oneshot_change(!hrtimer_is_hres_enabled()))
-		hrtimer_switch_to_hres();
+		hrtimer_switch_to_hres(cpu_base);
 }
 
 /*
@@ -1467,11 +1473,12 @@ void hrtimer_run_pending(void)
 void hrtimer_run_queues(void)
 {
 	struct rb_node *node;
-	struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases);
+	struct hrtimer_cpu_base *cpu_base;
 	struct hrtimer_clock_base *base;
 	int index, gettime = 1;
 
-	if (hrtimer_hres_active())
+	cpu_base = &per_cpu(hrtimer_bases, raw_smp_processor_id());
+	if (hrtimer_hres_active(cpu_base))
 		return;
 
 	for (index = 0; index < HRTIMER_MAX_CLOCK_BASES; index++) {
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index d5a267d..4881995 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -3438,7 +3438,7 @@ out:
  */
 static void run_rebalance_domains(struct softirq_action *h)
 {
-	int this_cpu = smp_processor_id();
+	int this_cpu = raw_smp_processor_id();
 	struct rq *this_rq = cpu_rq(this_cpu);
 	enum cpu_idle_type idle = this_rq->idle_at_tick ?
 						CPU_IDLE : CPU_NOT_IDLE;
diff --git a/kernel/timer.c b/kernel/timer.c
index f0d478a..8f29bd0 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -1274,7 +1274,7 @@ void update_process_times(int user_tick)
  */
 static void run_timer_softirq(struct softirq_action *h)
 {
-	struct tvec_base *base = __get_cpu_var(tvec_bases);
+	struct tvec_base *base = per_cpu(tvec_bases, raw_smp_processor_id());
 
 	printk_tick();
 	hrtimer_run_pending();
-- 
1.7.1.1