Linus,

Please pull the latest timers-urgent-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
timers-urgent-for-linus

   HEAD: 5a8e01f8fa51f5cbce8f37acc050eb2319d12956 sched/cputime: Do not scale 
when utime == 0

This fixes a longer-standing cputime accounting bug that Stanislaw Gruszka 
finally managed to track down.

 Thanks,

        Ingo

------------------>
Stanislaw Gruszka (1):
      sched/cputime: Do not scale when utime == 0


 kernel/sched/cputime.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index c1d7493..5b03f5b 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -551,10 +551,7 @@ static void cputime_adjust(struct task_cputime *curr,
                           struct cputime *prev,
                           cputime_t *ut, cputime_t *st)
 {
-       cputime_t rtime, stime, utime, total;
-
-       stime = curr->stime;
-       total = stime + curr->utime;
+       cputime_t rtime, stime, utime;
 
        /*
         * Tick based cputime accounting depend on random scheduling
@@ -576,13 +573,19 @@ static void cputime_adjust(struct task_cputime *curr,
        if (prev->stime + prev->utime >= rtime)
                goto out;
 
-       if (total) {
+       stime = curr->stime;
+       utime = curr->utime;
+
+       if (utime == 0) {
+               stime = rtime;
+       } else if (stime == 0) {
+               utime = rtime;
+       } else {
+               cputime_t total = stime + utime;
+
                stime = scale_stime((__force u64)stime,
                                    (__force u64)rtime, (__force u64)total);
                utime = rtime - stime;
-       } else {
-               stime = rtime;
-               utime = 0;
        }
 
        /*
--
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