1 files changed, 24 insertions, 18 deletions

diff --git a/arch/s390/kernel/vtime.c b/arch/s390/kernel/vtime.c
index 4fc97b40a6e..8c34363d6f1 100644
--- a/arch/s390/kernel/vtime.c
+++ b/arch/s390/kernel/vtime.c
@@ -19,6 +19,7 @@
 #include <asm/irq_regs.h>
 #include <asm/cputime.h>
 #include <asm/vtimer.h>
+#include <asm/vtime.h>
 #include <asm/irq.h>
 #include "entry.h"
 
@@ -99,7 +100,7 @@ static int do_account_vtime(struct task_struct *tsk, int hardirq_offset)
 	return virt_timer_forward(user + system);
 }
 
-void account_vtime(struct task_struct *prev, struct task_struct *next)
+void vtime_task_switch(struct task_struct *prev)
 {
 	struct thread_info *ti;
 
@@ -107,12 +108,17 @@ void account_vtime(struct task_struct *prev, struct task_struct *next)
 	ti = task_thread_info(prev);
 	ti->user_timer = S390_lowcore.user_timer;
 	ti->system_timer = S390_lowcore.system_timer;
-	ti = task_thread_info(next);
+	ti = task_thread_info(current);
 	S390_lowcore.user_timer = ti->user_timer;
 	S390_lowcore.system_timer = ti->system_timer;
 }
 
-void account_process_tick(struct task_struct *tsk, int user_tick)
+/*
+ * In s390, accounting pending user time also implies
+ * accounting system time in order to correctly compute
+ * the stolen time accounting.
+ */
+void vtime_account_user(struct task_struct *tsk)
 {
 	if (do_account_vtime(tsk, HARDIRQ_OFFSET))
 		virt_timer_expire();
@@ -122,11 +128,13 @@ void account_process_tick(struct task_struct *tsk, int user_tick)
  * Update process times based on virtual cpu times stored by entry.S
  * to the lowcore fields user_timer, system_timer & steal_clock.
  */
-void account_system_vtime(struct task_struct *tsk)
+void vtime_account_irq_enter(struct task_struct *tsk)
 {
 	struct thread_info *ti = task_thread_info(tsk);
 	u64 timer, system;
 
+	WARN_ON_ONCE(!irqs_disabled());
+
 	timer = S390_lowcore.last_update_timer;
 	S390_lowcore.last_update_timer = get_vtimer();
 	S390_lowcore.system_timer += timer - S390_lowcore.last_update_timer;
@@ -138,7 +146,11 @@ void account_system_vtime(struct task_struct *tsk)
 
 	virt_timer_forward(system);
 }
-EXPORT_SYMBOL_GPL(account_system_vtime);
+EXPORT_SYMBOL_GPL(vtime_account_irq_enter);
+
+void vtime_account_system(struct task_struct *tsk)
+__attribute__((alias("vtime_account_irq_enter")));
+EXPORT_SYMBOL_GPL(vtime_account_system);
 
 void __kprobes vtime_stop_cpu(void)
 {
@@ -147,20 +159,15 @@ void __kprobes vtime_stop_cpu(void)
 	unsigned long psw_mask;
 
 	trace_hardirqs_on();
-	/* Don't trace preempt off for idle. */
-	stop_critical_timings();
 
 	/* Wait for external, I/O or machine check interrupt. */
-	psw_mask = psw_kernel_bits | PSW_MASK_WAIT | PSW_MASK_DAT |
+	psw_mask = PSW_KERNEL_BITS | PSW_MASK_WAIT | PSW_MASK_DAT |
 		PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
 	idle->nohz_delay = 0;
 
 	/* Call the assembler magic in entry.S */
 	psw_idle(idle, psw_mask);
 
-	/* Reenable preemption tracer. */
-	start_critical_timings();
-
 	/* Account time spent with enabled wait psw loaded as idle time. */
 	idle->sequence++;
 	smp_wmb();
@@ -180,11 +187,11 @@ cputime64_t s390_get_idle_time(int cpu)
 	unsigned int sequence;
 
 	do {
-		now = get_clock();
+		now = get_tod_clock();
 		sequence = ACCESS_ONCE(idle->sequence);
 		idle_enter = ACCESS_ONCE(idle->clock_idle_enter);
 		idle_exit = ACCESS_ONCE(idle->clock_idle_exit);
-	} while ((sequence & 1) || (idle->sequence != sequence));
+	} while ((sequence & 1) || (ACCESS_ONCE(idle->sequence) != sequence));
 	return idle_enter ? ((idle_exit ?: now) - idle_enter) : 0;
 }
 
@@ -365,22 +372,21 @@ EXPORT_SYMBOL(del_virt_timer);
 /*
  * Start the virtual CPU timer on the current CPU.
  */
-void __cpuinit init_cpu_vtimer(void)
+void init_cpu_vtimer(void)
 {
 	/* set initial cpu timer */
 	set_vtimer(VTIMER_MAX_SLICE);
 }
 
-static int __cpuinit s390_nohz_notify(struct notifier_block *self,
-				      unsigned long action, void *hcpu)
+static int s390_nohz_notify(struct notifier_block *self, unsigned long action,
+			    void *hcpu)
 {
 	struct s390_idle_data *idle;
 	long cpu = (long) hcpu;
 
 	idle = &per_cpu(s390_idle, cpu);
-	switch (action) {
+	switch (action & ~CPU_TASKS_FROZEN) {
 	case CPU_DYING:
-	case CPU_DYING_FROZEN:
 		idle->nohz_delay = 0;
 	default:
 		break;