From ade7e19c88acc0a58dc9c58e15ccd91c103c836d Mon Sep 17 00:00:00 2001
From: Glauber Costa <glommer@redhat.com>
Date: Mon, 11 Jul 2011 15:28:17 -0400
Subject: [PATCH] --- yaml --- r: 258086 b: refs/heads/master c:
 e6e6685accfa81f509fadfc9624bc7c3862d75c4 h: refs/heads/master v: v3

---
 [refs]               |  2 +-
 trunk/kernel/sched.c | 43 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 79cfde2caafc..f474721a660e 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 747f2925836b678d2a0de980d70101fd35620f2a
+refs/heads/master: e6e6685accfa81f509fadfc9624bc7c3862d75c4
diff --git a/trunk/kernel/sched.c b/trunk/kernel/sched.c
index 3f2e502d609b..f98a28b19b2a 100644
--- a/trunk/kernel/sched.c
+++ b/trunk/kernel/sched.c
@@ -75,6 +75,9 @@
 #include <asm/tlb.h>
 #include <asm/irq_regs.h>
 #include <asm/mutex.h>
+#ifdef CONFIG_PARAVIRT
+#include <asm/paravirt.h>
+#endif
 
 #include "sched_cpupri.h"
 #include "workqueue_sched.h"
@@ -528,6 +531,9 @@ struct rq {
 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
 	u64 prev_irq_time;
 #endif
+#ifdef CONFIG_PARAVIRT
+	u64 prev_steal_time;
+#endif
 
 	/* calc_load related fields */
 	unsigned long calc_load_update;
@@ -1953,6 +1959,18 @@ void account_system_vtime(struct task_struct *curr)
 }
 EXPORT_SYMBOL_GPL(account_system_vtime);
 
+#endif /* CONFIG_IRQ_TIME_ACCOUNTING */
+
+#ifdef CONFIG_PARAVIRT
+static inline u64 steal_ticks(u64 steal)
+{
+	if (unlikely(steal > NSEC_PER_SEC))
+		return div_u64(steal, TICK_NSEC);
+
+	return __iter_div_u64_rem(steal, TICK_NSEC, &steal);
+}
+#endif
+
 static void update_rq_clock_task(struct rq *rq, s64 delta)
 {
 	s64 irq_delta;
@@ -3845,6 +3863,25 @@ void account_idle_time(cputime_t cputime)
 		cpustat->idle = cputime64_add(cpustat->idle, cputime64);
 }
 
+static __always_inline bool steal_account_process_tick(void)
+{
+#ifdef CONFIG_PARAVIRT
+	if (static_branch(&paravirt_steal_enabled)) {
+		u64 steal, st = 0;
+
+		steal = paravirt_steal_clock(smp_processor_id());
+		steal -= this_rq()->prev_steal_time;
+
+		st = steal_ticks(steal);
+		this_rq()->prev_steal_time += st * TICK_NSEC;
+
+		account_steal_time(st);
+		return st;
+	}
+#endif
+	return false;
+}
+
 #ifndef CONFIG_VIRT_CPU_ACCOUNTING
 
 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
@@ -3876,6 +3913,9 @@ static void irqtime_account_process_tick(struct task_struct *p, int user_tick,
 	cputime64_t tmp = cputime_to_cputime64(cputime_one_jiffy);
 	struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
 
+	if (steal_account_process_tick())
+		return;
+
 	if (irqtime_account_hi_update()) {
 		cpustat->irq = cputime64_add(cpustat->irq, tmp);
 	} else if (irqtime_account_si_update()) {
@@ -3929,6 +3969,9 @@ void account_process_tick(struct task_struct *p, int user_tick)
 		return;
 	}
 
+	if (steal_account_process_tick())
+		return;
+
 	if (user_tick)
 		account_user_time(p, cputime_one_jiffy, one_jiffy_scaled);
 	else if ((p != rq->idle) || (irq_count() != HARDIRQ_OFFSET))