Re: [Qemu-devel] [PATCH v6 22/25] replay: add BH oneshot event for block layer

["Pavel Dovgalyuk" <dovgaluk@ispras.ru>]

> From: Paolo Bonzini [mailto:pbonzini@redhat.com]
> On 13/09/2018 13:13, Pavel Dovgalyuk wrote:
> >> From: Paolo Bonzini [mailto:pbonzini@redhat.com]
> >> On 12/09/2018 10:19, Pavel Dovgalyuk wrote:
> >>> + uint64_t id = replay_get_current_step();
> >>> + replay_add_event(REPLAY_ASYNC_EVENT_BH_ONESHOT, cb, opaque, id);
> >>
> >> Why does it need an id, while REPLAY_ASYNC_EVENT_BH does not?
> >
> > Because _oneshot() function takes only context and callback,
> > and BH object is created inside that function.
> > Therefore to use the normal bh scheduling events we have to refactor
> > block code - add bh creation, scheduling, and freeing.
> 
> No, I'm asking only why the id is 0 for REPLAY_ASYNC_EVENT_BH and
> replay_get_current_step() for REPLAY_ASYNC_EVENT_BH_ONESHOT.
> 
> Thanks,
> 
> Paolo

Sorry, I missed your point.
Maybe you looked at the wrong function, because both of these events have an id:

void replay_bh_schedule_event(QEMUBH *bh)
{
    if (events_enabled) {
        uint64_t id = replay_get_current_step();
        replay_add_event(REPLAY_ASYNC_EVENT_BH, bh, NULL, id);
    } else {
        qemu_bh_schedule(bh);
    }
}

void replay_bh_schedule_oneshot_event(AioContext *ctx,
    QEMUBHFunc *cb, void *opaque)
{
    if (events_enabled) {
        uint64_t id = replay_get_current_step();
        replay_add_event(REPLAY_ASYNC_EVENT_BH_ONESHOT, cb, opaque, id);
    } else {
        aio_bh_schedule_oneshot(ctx, cb, opaque);
    }
}

Pavel Dovgalyuk