On Fri, Mar 03, 2017 at 12:17:08PM +0000, Chris Wilson wrote: > Refactor the common task of updating the first_waiter, serialised with > the interrupt handler. When we update the first_waiter, we also need to > wakeup the new bottom-half in order to complete the actions that we may > have delegated to it (such as checking the irq-seqno coherency or waking > up other lower priority concurrent waiters). > > Signed-off-by: Chris Wilson <[email protected]> > --- > drivers/gpu/drm/i915/intel_breadcrumbs.c | 48 > +++++++++++++------------------- > 1 file changed, 19 insertions(+), 29 deletions(-) > > diff --git a/drivers/gpu/drm/i915/intel_breadcrumbs.c > b/drivers/gpu/drm/i915/intel_breadcrumbs.c > index 235d4645a5cf..1cc50304f824 100644 > --- a/drivers/gpu/drm/i915/intel_breadcrumbs.c > +++ b/drivers/gpu/drm/i915/intel_breadcrumbs.c > @@ -287,6 +287,21 @@ static inline void __intel_breadcrumbs_finish(struct > intel_breadcrumbs *b, > wake_up_process(wait->tsk); /* implicit smp_wmb() */ > } > > +static inline void __intel_breadcrumbs_next(struct intel_engine_cs *engine, > + struct rb_node *next) > +{ > + struct intel_breadcrumbs *b = &engine->breadcrumbs; > + > + GEM_BUG_ON(!b->irq_armed); > + b->first_wait = to_wait(next); > + > + /* We always wake up the next waiter that takes over as the bottom-half > + * as we may delegate not only the irq-seqno barrier to the next waiter > + * but also the task of waking up concurrent waiters. > + */ > + wake_up_process(to_wait(next)->tsk);
Alternatively: - wake_up_process(to_wait(next)->tsk); + if ((engine->irq_seqno_barrier && + test_bit(ENGINE_IRQ_BREADCRUMB, &engine->irq_posted)) || + i915_seqno_passed(intel_engine_get_seqno(engine), + to_wait(next)->seqno)) + wake_up_process(to_wait(next)->tsk); A plain wake_up_process() is certainly much less fragile. -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
