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-rw-r--r--kernel/sched/cputime.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index e9198ab..1b7c216 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -581,6 +581,14 @@ static void cputime_adjust(struct task_cputime *curr,
*/
rtime = nsecs_to_cputime(curr->sum_exec_runtime);
+ /*
+ * Update userspace visible utime/stime values only if actual execution
+ * time is bigger than already exported. Note that can happen, that we
+ * provided bigger values due to scaling inaccuracy on big numbers.
+ */
+ if (prev->stime + prev->utime >= rtime)
+ goto out;
+
if (!rtime) {
stime = 0;
} else if (!total) {
@@ -598,6 +606,7 @@ static void cputime_adjust(struct task_cputime *curr,
prev->stime = max(prev->stime, stime);
prev->utime = max(prev->utime, rtime - prev->stime);
+out:
*ut = prev->utime;
*st = prev->stime;
}
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