Broadcast device is switched to oneshot mode in
hrtimer_switch_to_hres() -> tick_broadcast_switch_to_oneshot().
After high resolution timers are enabled, new installed
broadcast device has no chance to switch mode.
This issue happens in below situation:
In order to make broadcast clock source driver build as module,
use module_platform_driver() to replace TIMER_OF_DECLARE().
This will make clock source driver probed later than
high resolution timers enabled.
Signed-off-by: Jindong Yue <jindong....@nxp.com>
---
kernel/time/tick-broadcast.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index e51778c312f1..f38a7544cb5b 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -47,6 +47,7 @@ static inline void tick_resume_broadcast_oneshot(struct
clock_event_device *bc)
static inline void tick_broadcast_oneshot_offline(unsigned int cpu) { }
# endif
#endif
+static void tick_handle_oneshot_broadcast(struct clock_event_device *dev);
/*
* Debugging: see timer_list.c
@@ -115,8 +116,20 @@ void tick_install_broadcast_device(struct
clock_event_device *dev)
* notification the systems stays stuck in periodic mode
* forever.
*/
- if (dev->features & CLOCK_EVT_FEAT_ONESHOT)
+ if (dev->features & CLOCK_EVT_FEAT_ONESHOT) {
tick_clock_notify();
+
+ /*
+ * If new broadcast device is installed after high resolution
+ * timers enabled, it can not switch to oneshot mode anymore.
+ * Here give it a chance.
+ */
+ if (tick_broadcast_oneshot_active() &&
+ dev->event_handler != tick_handle_oneshot_broadcast) {
+ tick_broadcast_switch_to_oneshot();
+ }
+ }
+
}
/*
--
2.17.1
