On Wed, Aug 15, 2018 at 10:03:13AM -0700, Song Liu wrote:
SNIP
> @@ -6100,7 +6333,7 @@ static void perf_output_read_group(struct
> perf_output_handle *handle,
>
> if ((sub != event) &&
> (sub->state == PERF_EVENT_STATE_ACTIVE))
> - sub->pmu->read(sub);
> + event_pmu_read(sub);
>
> values[n++] = perf_event_count(sub);
> if (read_format & PERF_FORMAT_ID)
> @@ -9109,7 +9342,7 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct
> hrtimer *hrtimer)
> if (event->state != PERF_EVENT_STATE_ACTIVE)
> return HRTIMER_NORESTART;
>
> - event->pmu->read(event);
> + event_pmu_read(event);
>
> perf_sample_data_init(&data, 0, event->hw.last_period);
> regs = get_irq_regs();
> @@ -10504,6 +10737,14 @@ SYSCALL_DEFINE5(perf_event_open,
> goto err_cred;
> }
>
> + if (perf_event_can_share(event)) {
> + event->tmp_master = perf_event_alloc(&event->attr, cpu,
> + task, NULL, NULL,
> + NULL, NULL, -1);
can't get around this.. I understand the need, but AFAICS you allocate
the whole 'struct perf_event', just because there's count field in it
otherwise the 'struct hw_perf_event' should be enough to carry all that's
needed to read hw event
would it be better to move the count to 'struct hw_perf_event' and use
that instead? assuming I'm not missing anything..
jirka
