sched: disable the hrtick for now

commit 0c4b83da58ec2e96ce9c44c211d6eac5f9dae478 upstream

sched: disable the hrtick for now

David Miller reported that hrtick update overhead has tripled the
wakeup overhead on Sparc64.

That is too much - disable the HRTICK feature for now by default,
until a faster implementation is found.

Reported-by: David Miller <davem@davemloft.net>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/kernel/sched_features.h b/kernel/sched_features.h
index 9353ca7..c4c88ae 100644 (file)
--- a/kernel/sched_features.h
+++ b/kernel/sched_features.h
@@ -5,7 +5,7 @@ SCHED_FEAT(START_DEBIT, 1)
 SCHED_FEAT(AFFINE_WAKEUPS, 1)
 SCHED_FEAT(CACHE_HOT_BUDDY, 1)
 SCHED_FEAT(SYNC_WAKEUPS, 1)
-SCHED_FEAT(HRTICK, 1)
+SCHED_FEAT(HRTICK, 0)
 SCHED_FEAT(DOUBLE_TICK, 0)
 SCHED_FEAT(ASYM_GRAN, 1)
 SCHED_FEAT(LB_BIAS, 1)