> +/*
> + * Bit values to track state of the timer
> + *
> + * Possible states:
> + *
> + * 0x00 inactive
> + * 0x01 enqueued into rbtree
> + * 0x02 callback function running
> + * 0x03 callback function running and enqueued
> + * (was requeued on another CPU)
> + *
> + * The "callback function running and enqueued" status is only possible on
> + * SMP. It happens for example when a posix timer expired and the callback
> + * queued a signal. Between dropping the lock which protects the posix timer
> + * and reacquiring the base lock of the hrtimer, another CPU can deliver the
> + * signal and rearm the timer. We have to preserve the callback running state,
> + * as otherwise the timer could be removed before the softirq code finishes the
> + * the handling of the timer.
> + *
> + * The HRTIMER_STATE_ENQUEUE bit is always or'ed to the current state to
> + * preserve the HRTIMER_STATE_CALLBACK bit in the above scenario.
> + *
> + * All state transitions are protected by cpu_base->lock.
> + */
> +#define HRTIMER_STATE_INACTIVE 0x00
> +#define HRTIMER_STATE_ENQUEUED 0x01
> +#define HRTIMER_STATE_CALLBACK 0x02
where is the define for 0x03?
>
> +static inline int hrtimer_is_queued(struct hrtimer *timer)
> +{
> + return timer->state != HRTIMER_STATE_INACTIVE &&
> + timer->state != HRTIMER_STATE_CALLBACK;
> +}
the state things are either bits or they're not. If they're bits, you
probably want to make this a bitcheck instead...
> rb_insert_color(&timer->node, &base->active);
> + /*
> + * HRTIMER_STATE_ENQUEUED is or'ed to the current state to preserve the
> + * state of a possibly running callback.
> + */
> + timer->state |= HRTIMER_STATE_ENQUEUED;
ok so it IS a bit thing, see comment about hrtimer_is_queued() not being
a bit check then...
> - if (base->cpu_base->curr_timer != timer)
> + if (!(timer->state & HRTIMER_STATE_CALLBACK))
> ret = remove_hrtimer(timer, base);
if there is a hrtimer_is_queued() inline, might as well make a
hrtimer_is_running() inline as well
otherwise lookes ok; if you fix these few comments:
Acked-by: Arjan van de Ven <[email protected]>
--
if you want to mail me at work (you don't), use arjan (at) linux.intel.com
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