lkml.org 
[lkml]   [2019]   [Jul]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] cpuidle: Always stop scheduler tick on adaptive-tick CPUs
Date
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Running the scheduler tick on idle adaptive-tick CPUs is not useful
and it may also be not expected by users (as reported by Thomas), so
add a check to cpuidle_idle_call() to always stop the tick on them
regardless of the idle duration predicted by the governor.

Fixes: 554c8aa8ecad ("sched: idle: Select idle state before stopping the tick")
Reported-by: Thomas Lindroth <thomas.lindroth@gmail.com>
Tested-by: Thomas Lindroth <thomas.lindroth@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
kernel/sched/idle.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

Index: linux-pm/kernel/sched/idle.c
===================================================================
--- linux-pm.orig/kernel/sched/idle.c
+++ linux-pm/kernel/sched/idle.c
@@ -191,7 +191,8 @@ static void cpuidle_idle_call(void)
*/
next_state = cpuidle_select(drv, dev, &stop_tick);

- if (stop_tick || tick_nohz_tick_stopped())
+ if (stop_tick || tick_nohz_tick_stopped() ||
+ !housekeeping_cpu(dev->cpu, HK_FLAG_TICK))
tick_nohz_idle_stop_tick();
else
tick_nohz_idle_retain_tick();


\
 
 \ /
  Last update: 2019-07-16 17:26    [W:0.060 / U:3.516 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site