On Mon, Aug 24, 2015 at 05:20:20PM +0300, Alexey Brodkin wrote:
> @@ -139,9 +141,11 @@ static int arc_pmu_event_init(struct perf_event *event)
>       struct hw_perf_event *hwc = &event->hw;
>       int ret;
>  
> -     hwc->sample_period  = arc_pmu->max_period;
> -     hwc->last_period = hwc->sample_period;
> -     local64_set(&hwc->period_left, hwc->sample_period);
> +     if (!is_sampling_event(event)) {
> +             hwc->sample_period  = arc_pmu->max_period;
> +             hwc->last_period = hwc->sample_period;
> +             local64_set(&hwc->period_left, hwc->sample_period);
> +     }

So here we set a max_period sample period for !sampling events such that
we can properly deal with (short) counter overflow and accumulate into a
64bit value.

>       switch (event->attr.type) {
>       case PERF_TYPE_HARDWARE:
> @@ -243,6 +247,11 @@ static void arc_pmu_start(struct perf_event *event, int 
> flags)
>  
>       arc_pmu_event_set_period(event);
>  
> +     /* Enable interrupt for this counter */
> +     if (is_sampling_event(event))
> +             write_aux_reg(ARC_REG_PCT_INT_CTRL,
> +                           read_aux_reg(ARC_REG_PCT_INT_CTRL) | (1 << idx));
> +

Yet here you fail to actually enable the interrupt for the non sampling
events, which makes the above not work.

>       /* enable ARC pmu here */
>       write_aux_reg(ARC_REG_PCT_INDEX, idx);
>       write_aux_reg(ARC_REG_PCT_CONFIG, hwc->config);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to