From: Wanpeng Li <wanpeng.li@xxxxxxxxxxxxxxx> This patch has been added to the 3.18 stable tree. If you have any objections, please let us know. =============== [ Upstream commit 868933359a3bdda25b562e9d41bce7071edc1b08 ] The commit 177ef2a6315e ("sched/deadline: Fix a precision problem in the microseconds range") forgot to change the UP version of hrtick_start(), do so now. Signed-off-by: Wanpeng Li <wanpeng.li@xxxxxxxxxxxxxxx> Fixes: 177ef2a6315e ("sched/deadline: Fix a precision problem in the microseconds range") [ Fixed the changelog. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Cc: Juri Lelli <juri.lelli@xxxxxxx> Cc: Kirill Tkhai <ktkhai@xxxxxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/1416962647-76792-7-git-send-email-wanpeng.li@xxxxxxxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx> --- kernel/sched/core.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index efdca2f..d745502 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -490,6 +490,11 @@ static __init void init_hrtick(void) */ void hrtick_start(struct rq *rq, u64 delay) { + /* + * Don't schedule slices shorter than 10000ns, that just + * doesn't make sense. Rely on vruntime for fairness. + */ + delay = max_t(u64, delay, 10000LL); __hrtimer_start_range_ns(&rq->hrtick_timer, ns_to_ktime(delay), 0, HRTIMER_MODE_REL_PINNED, 0); } -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html