On 2017-10-24 01:37, Thomas Gleixner wrote:
On Tue, 24 Oct 2017, Prasad Sodagudi wrote:
Currently tick_program_event function is not calling
clockevents_program_event when 'expires == KTIME_MAX',
it is just updating clockevent state to
CLOCK_EVT_STATE_ONESHOT_STOPPED.
clockevents_program_event function updates clockevent
device next_event by checking clockevent device state,
so always call clockevents_program_event() from tick_program_event.
No. This is fundmentally wrong. If the clockevent is in oneshot stopped
mode then you cannot call clockevents_program_event(). There is even a
warning in that code which will trigger.
<Prasad> Yes. There is warning and I overlooked at that part of the code
and thought
it would return from the clockevents_program_event function after
next_event update.
dev->next_event = expires;
if (clockevent_state_shutdown(dev))
return 0;
Thanks tglx for reviewing patch.
How to clean next next_event from clockevent device in the
ONESHOT_STOPPED state from tick_program_event()?
Shall I update the next patch set with following condition? Or Any
other suggestions to fix this path?
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index 4237e07..21104b6 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -317,7 +317,8 @@ int clockevents_program_event(struct
clock_event_device *dev, ktime_t expires,
dev->next_event = expires;
- if (clockevent_state_shutdown(dev))
+ if (clockevent_state_shutdown(dev) ||
+ clockevent_state_oneshot_stopped(dev))
return 0;
Thanks,
tglx
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