1 files changed, 54 insertions, 6 deletions

diff --git a/arch/s390/kernel/vtime.c b/arch/s390/kernel/vtime.c
index 7f0089d9a4a..e53d3595a7c 100644
--- a/arch/s390/kernel/vtime.c
+++ b/arch/s390/kernel/vtime.c
@@ -15,6 +15,8 @@
 #include <asm/cputime.h>
 #include <asm/vtimer.h>
 #include <asm/vtime.h>
+#include <asm/cpu_mf.h>
+#include <asm/smp.h>
 
 static void virt_timer_expire(void);
 
@@ -23,6 +25,10 @@ static DEFINE_SPINLOCK(virt_timer_lock);
 static atomic64_t virt_timer_current;
 static atomic64_t virt_timer_elapsed;
 
+static DEFINE_PER_CPU(u64, mt_cycles[32]);
+static DEFINE_PER_CPU(u64, mt_scaling_mult) = { 1 };
+static DEFINE_PER_CPU(u64, mt_scaling_div) = { 1 };
+
 static inline u64 get_vtimer(void)
 {
 	u64 timer;
@@ -61,6 +67,8 @@ static int do_account_vtime(struct task_struct *tsk, int hardirq_offset)
 {
 	struct thread_info *ti = task_thread_info(tsk);
 	u64 timer, clock, user, system, steal;
+	u64 user_scaled, system_scaled;
+	int i;
 
 	timer = S390_lowcore.last_update_timer;
 	clock = S390_lowcore.last_update_clock;
@@ -76,15 +84,49 @@ static int do_account_vtime(struct task_struct *tsk, int hardirq_offset)
 	S390_lowcore.system_timer += timer - S390_lowcore.last_update_timer;
 	S390_lowcore.steal_timer += S390_lowcore.last_update_clock - clock;
 
+	/* Do MT utilization calculation */
+	if (smp_cpu_mtid) {
+		u64 cycles_new[32], *cycles_old;
+		u64 delta, mult, div;
+
+		cycles_old = this_cpu_ptr(mt_cycles);
+		if (stcctm5(smp_cpu_mtid + 1, cycles_new) < 2) {
+			mult = div = 0;
+			for (i = 0; i <= smp_cpu_mtid; i++) {
+				delta = cycles_new[i] - cycles_old[i];
+				mult += delta;
+				div += (i + 1) * delta;
+			}
+			if (mult > 0) {
+				/* Update scaling factor */
+				__this_cpu_write(mt_scaling_mult, mult);
+				__this_cpu_write(mt_scaling_div, div);
+				memcpy(cycles_old, cycles_new,
+				       sizeof(u64) * (smp_cpu_mtid + 1));
+			}
+		}
+	}
+
 	user = S390_lowcore.user_timer - ti->user_timer;
 	S390_lowcore.steal_timer -= user;
 	ti->user_timer = S390_lowcore.user_timer;
-	account_user_time(tsk, user, user);
 
 	system = S390_lowcore.system_timer - ti->system_timer;
 	S390_lowcore.steal_timer -= system;
 	ti->system_timer = S390_lowcore.system_timer;
-	account_system_time(tsk, hardirq_offset, system, system);
+
+	user_scaled = user;
+	system_scaled = system;
+	/* Do MT utilization scaling */
+	if (smp_cpu_mtid) {
+		u64 mult = __this_cpu_read(mt_scaling_mult);
+		u64 div = __this_cpu_read(mt_scaling_div);
+
+		user_scaled = (user_scaled * mult) / div;
+		system_scaled = (system_scaled * mult) / div;
+	}
+	account_user_time(tsk, user, user_scaled);
+	account_system_time(tsk, hardirq_offset, system, system_scaled);
 
 	steal = S390_lowcore.steal_timer;
 	if ((s64) steal > 0) {
@@ -126,9 +168,7 @@ void vtime_account_user(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());
+	u64 timer, system, system_scaled;
 
 	timer = S390_lowcore.last_update_timer;
 	S390_lowcore.last_update_timer = get_vtimer();
@@ -137,7 +177,15 @@ void vtime_account_irq_enter(struct task_struct *tsk)
 	system = S390_lowcore.system_timer - ti->system_timer;
 	S390_lowcore.steal_timer -= system;
 	ti->system_timer = S390_lowcore.system_timer;
-	account_system_time(tsk, 0, system, system);
+	system_scaled = system;
+	/* Do MT utilization scaling */
+	if (smp_cpu_mtid) {
+		u64 mult = __this_cpu_read(mt_scaling_mult);
+		u64 div = __this_cpu_read(mt_scaling_div);
+
+		system_scaled = (system_scaled * mult) / div;
+	}
+	account_system_time(tsk, 0, system, system_scaled);
 
 	virt_timer_forward(system);
 }