[PATCH] fix scaled & unscaled cputime accounting

The utimescaled / stimescaled fields in the task structure and the
global cpustat should be set on all architectures. On s390 the calls
to account_user_time_scaled and account_system_time_scaled never have
been added. In addition system time that is accounted as guest time
to the user time of a process is accounted to the scaled system time
instead of the scaled user time.
To fix the bugs and to prevent future forgetfulness this patch merges
account_system_time_scaled into account_system_time and
account_user_time_scaled into account_user_time.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Michael Neuling <mikey@neuling.org>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 5 insertions, 7 deletions

diff --git a/kernel/timer.c b/kernel/timer.c
index 566257d1dc10..b5efb528aa1d 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -1023,13 +1023,11 @@ void account_process_tick(struct task_struct *p, int user_tick)
 {
         cputime_t one_jiffy = jiffies_to_cputime(1);
 
-        if (user_tick) {
-                account_user_time(p, one_jiffy);
-                account_user_time_scaled(p, cputime_to_scaled(one_jiffy));
-        } else {
-                account_system_time(p, HARDIRQ_OFFSET, one_jiffy);
-                account_system_time_scaled(p, cputime_to_scaled(one_jiffy));
-        }
+        if (user_tick)
+                account_user_time(p, one_jiffy, cputime_to_scaled(one_jiffy));
+        else
+                account_system_time(p, HARDIRQ_OFFSET, one_jiffy,
+                                    cputime_to_scaled(one_jiffy));
 }
 #endif