[PATCH 25/36] cputime: Push time to account_system_time() in nsecs

[Frederic Weisbecker <fweisbec@gmail.com>]

This is one more step toward converting cputime accounting to pure nsecs.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
---
 arch/ia64/kernel/time.c     |  2 +-
 arch/powerpc/kernel/time.c  |  3 ++-
 arch/s390/kernel/vtime.c    |  4 ++--
 include/linux/kernel_stat.h |  3 +--
 kernel/sched/cputime.c      | 38 ++++++++++++++++++--------------------
 5 files changed, 24 insertions(+), 26 deletions(-)

diff --git a/arch/ia64/kernel/time.c b/arch/ia64/kernel/time.c
index 0287ffe..0aba18e 100644
--- a/arch/ia64/kernel/time.c
+++ b/arch/ia64/kernel/time.c
@@ -113,7 +113,7 @@ void vtime_account_system(struct task_struct *tsk)
 {
 	cputime_t delta = vtime_delta(tsk);
 
-	account_system_time(tsk, 0, delta);
+	account_system_time(tsk, 0, cputime_to_nsecs(delta));
 }
 EXPORT_SYMBOL_GPL(vtime_account_system);
 
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 7cd3b3c..b29822d 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -358,8 +358,9 @@ void vtime_account_system(struct task_struct *tsk)
 	unsigned long delta, sys_scaled, stolen;
 
 	delta = vtime_delta(tsk, &sys_scaled, &stolen);
-	account_system_time(tsk, 0, delta);
+	account_system_time(tsk, 0, cputime_to_nsecs(delta));
 	tsk->stimescaled += cputime_to_nsecs(sys_scaled);
+
 	if (stolen)
 		account_steal_time(cputime_to_nsecs(stolen));
 }
diff --git a/arch/s390/kernel/vtime.c b/arch/s390/kernel/vtime.c
index 02c3970..b7e545f 100644
--- a/arch/s390/kernel/vtime.c
+++ b/arch/s390/kernel/vtime.c
@@ -139,7 +139,7 @@ static int do_account_vtime(struct task_struct *tsk, int hardirq_offset)
 	}
 	account_user_time(tsk, cputime_to_nsecs(user));
 	tsk->utimescaled += cputime_to_nsecs(user_scaled);
-	account_system_time(tsk, hardirq_offset, system);
+	account_system_time(tsk, hardirq_offset, cputime_to_nsecs(system));
 	tsk->stimescaled += cputime_to_nsecs(system_scaled);
 
 	steal = S390_lowcore.steal_timer;
@@ -204,7 +204,7 @@ void vtime_account_irq_enter(struct task_struct *tsk)
 
 		system_scaled = (system_scaled * mult) / div;
 	}
-	account_system_time(tsk, 0, system);
+	account_system_time(tsk, 0, cputime_to_nsecs(system));
 	tsk->stimescaled += cputime_to_nsecs(system_scaled);
 
 	virt_timer_forward(system);
diff --git a/include/linux/kernel_stat.h b/include/linux/kernel_stat.h
index 07b103e..ea6f359 100644
--- a/include/linux/kernel_stat.h
+++ b/include/linux/kernel_stat.h
@@ -9,7 +9,6 @@
 #include <linux/sched.h>
 #include <linux/vtime.h>
 #include <asm/irq.h>
-#include <linux/cputime.h>
 
 /*
  * 'kernel_stat.h' contains the definitions needed for doing
@@ -79,7 +78,7 @@ static inline unsigned int kstat_cpu_irqs_sum(unsigned int cpu)
 }
 
 extern void account_user_time(struct task_struct *, u64);
-extern void account_system_time(struct task_struct *, int, cputime_t);
+extern void account_system_time(struct task_struct *, int, u64);
 extern void account_steal_time(u64);
 extern void account_idle_time(u64);
 
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index ac9aa7e..8d541e7 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -138,22 +138,22 @@ void account_user_time(struct task_struct *p, u64 cputime)
  * @p: the process that the cpu time gets accounted to
  * @cputime: the cpu time spent in virtual machine since the last update
  */
-static void account_guest_time(struct task_struct *p, cputime_t cputime)
+static void account_guest_time(struct task_struct *p, u64 cputime)
 {
 	u64 *cpustat = kcpustat_this_cpu->cpustat;
 
 	/* Add guest time to process. */
-	p->utime += cputime_to_nsecs(cputime);
-	account_group_user_time(p, cputime_to_nsecs(cputime));
-	p->gtime += cputime_to_nsecs(cputime);
+	p->utime += cputime;
+	account_group_user_time(p, cputime);
+	p->gtime += cputime;
 
 	/* Add guest time to cpustat. */
 	if (task_nice(p) > 0) {
-		cpustat[CPUTIME_NICE] += cputime_to_nsecs(cputime);
-		cpustat[CPUTIME_GUEST_NICE] += cputime_to_nsecs(cputime);
+		cpustat[CPUTIME_NICE] += cputime;
+		cpustat[CPUTIME_GUEST_NICE] += cputime;
 	} else {
-		cpustat[CPUTIME_USER] += cputime_to_nsecs(cputime);
-		cpustat[CPUTIME_GUEST] += cputime_to_nsecs(cputime);
+		cpustat[CPUTIME_USER] += cputime;
+		cpustat[CPUTIME_GUEST] += cputime;
 	}
 }
 
@@ -164,14 +164,14 @@ static void account_guest_time(struct task_struct *p, cputime_t cputime)
  * @index: pointer to cpustat field that has to be updated
  */
 static inline
-void __account_system_time(struct task_struct *p, cputime_t cputime, int index)
+void __account_system_time(struct task_struct *p, u64 cputime, int index)
 {
 	/* Add system time to process. */
-	p->stime += cputime_to_nsecs(cputime);
-	account_group_system_time(p, cputime_to_nsecs(cputime));
+	p->stime += cputime;
+	account_group_system_time(p, cputime);
 
 	/* Add system time to cpustat. */
-	task_group_account_field(p, index, cputime_to_nsecs(cputime));
+	task_group_account_field(p, index, cputime);
 
 	/* Account for system time used */
 	acct_account_cputime(p);
@@ -183,8 +183,7 @@ void __account_system_time(struct task_struct *p, cputime_t cputime, int index)
  * @hardirq_offset: the offset to subtract from hardirq_count()
  * @cputime: the cpu time spent in kernel space since the last update
  */
-void account_system_time(struct task_struct *p, int hardirq_offset,
-			 cputime_t cputime)
+void account_system_time(struct task_struct *p, int hardirq_offset, u64 cputime)
 {
 	int index;
 
@@ -388,16 +387,15 @@ static void irqtime_account_process_tick(struct task_struct *p, int user_tick,
 		 * So, we have to handle it separately here.
 		 * Also, p->stime needs to be updated for ksoftirqd.
 		 */
-		__account_system_time(p, old_cputime, CPUTIME_SOFTIRQ);
+		__account_system_time(p, cputime, CPUTIME_SOFTIRQ);
 	} else if (user_tick) {
 		account_user_time(p, cputime);
 	} else if (p == rq->idle) {
 		account_idle_time(cputime);
 	} else if (p->flags & PF_VCPU) { /* System time or guest time */
-
-		account_guest_time(p, old_cputime);
+		account_guest_time(p, cputime);
 	} else {
-		__account_system_time(p, old_cputime, CPUTIME_SYSTEM);
+		__account_system_time(p, cputime, CPUTIME_SYSTEM);
 	}
 }
 
@@ -504,7 +502,7 @@ void account_process_tick(struct task_struct *p, int user_tick)
 	if (user_tick)
 		account_user_time(p, cputime);
 	else if ((p != rq->idle) || (irq_count() != HARDIRQ_OFFSET))
-		account_system_time(p, HARDIRQ_OFFSET, old_cputime);
+		account_system_time(p, HARDIRQ_OFFSET, cputime);
 	else
 		account_idle_time(cputime);
 }
@@ -724,7 +722,7 @@ static void __vtime_account_system(struct task_struct *tsk)
 {
 	cputime_t delta_cpu = get_vtime_delta(tsk);
 
-	account_system_time(tsk, irq_count(), delta_cpu);
+	account_system_time(tsk, irq_count(), cputime_to_nsecs(delta_cpu));
 }
 
 void vtime_account_system(struct task_struct *tsk)
-- 
2.7.4