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authorLinus Torvalds <torvalds@linux-foundation.org>2013-09-05 12:36:46 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-09-05 12:36:46 -0700
commit57d730924d5cc2c3e280af16a9306587c3a511db (patch)
tree78e4c6386f40bdaa1c3a9af869bcdc9b1a52818c
parent050ba07cdc9aaef17e1be251aa8fceb9a919d5d3 (diff)
parent5a8e01f8fa51f5cbce8f37acc050eb2319d12956 (diff)
Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull cputime fix from Ingo Molnar: "This fixes a longer-standing cputime accounting bug that Stanislaw Gruszka finally managed to track down" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/cputime: Do not scale when utime == 0
-rw-r--r--kernel/sched/cputime.c19
1 files changed, 11 insertions, 8 deletions
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index ace34f95e200..99947919e30b 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;
}
/*