cputime: Use accessors to read task cputime stats

This is in preparation for the full dynticks feature. While
remotely reading the cputime of a task running in a full
dynticks CPU, we'll need to do some extra-computation. This
way we can account the time it spent tickless in userspace
since its last cputime snapshot.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 4 insertions, 2 deletions

diff --git a/kernel/acct.c b/kernel/acct.c
index 051e071a06e7..e8b1627ab9c7 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -566,6 +566,7 @@ out:
 void acct_collect(long exitcode, int group_dead)
 {
         struct pacct_struct *pacct = &current->signal->pacct;
+        cputime_t utime, stime;
         unsigned long vsize = 0;
 
         if (group_dead && current->mm) {
@@ -593,8 +594,9 @@ void acct_collect(long exitcode, int group_dead)
                 pacct->ac_flag |= ACORE;
         if (current->flags & PF_SIGNALED)
                 pacct->ac_flag |= AXSIG;
-        pacct->ac_utime += current->utime;
-        pacct->ac_stime += current->stime;
+        task_cputime(current, &utime, &stime);
+        pacct->ac_utime += utime;
+        pacct->ac_stime += stime;
         pacct->ac_minflt += current->min_flt;
         pacct->ac_majflt += current->maj_flt;
         spin_unlock_irq(&current->sighand->siglock);