cpu_relax on ARM64 does a simple "yield". Thus we replace it with smp_cond_load_relaxed which basically does a "wfe". Suggested-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Signed-off-by: Mihai Carabas <mihai.carabas@xxxxxxxxxx> --- drivers/cpuidle/poll_state.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/cpuidle/poll_state.c b/drivers/cpuidle/poll_state.c index 9b6d90a72601..1e45be906e72 100644 --- a/drivers/cpuidle/poll_state.c +++ b/drivers/cpuidle/poll_state.c @@ -13,6 +13,7 @@ static int __cpuidle poll_idle(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index) { + unsigned long ret; u64 time_start; time_start = local_clock_noinstr(); @@ -26,12 +27,16 @@ static int __cpuidle poll_idle(struct cpuidle_device *dev, limit = cpuidle_poll_time(drv, dev); - while (!need_resched()) { - cpu_relax(); - if (loop_count++ < POLL_IDLE_RELAX_COUNT) - continue; - + for (;;) { loop_count = 0; + + ret = smp_cond_load_relaxed(¤t_thread_info()->flags, + VAL & _TIF_NEED_RESCHED || + loop_count++ >= POLL_IDLE_RELAX_COUNT); + + if (!(ret & _TIF_NEED_RESCHED)) + break; + if (local_clock_noinstr() - time_start > limit) { dev->poll_time_limit = true; break; -- 1.8.3.1