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    SubjectRe: [PATCH] Clockevents: Always call clockevents_program_event
    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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