We use the completion of the last active breadcrumb to retire the requests along a timeline. This is purely opportunistic as nothing guarantees that any particular timeline is terminated by a breadcrumb; except for parking the engine where we explicitly add a breadcrumb so that we park quickly and do an explicit retire upon signaling to reduce the latency dramatically (avoiding a retire worker roundtrip).
With scheduling, we anticipate retiring completed timelines as a matter of course. Performing the same action from inside the breadcrumbs is intended to provide similar functionality for legacy ringbuffer submission. Signed-off-by: Chris Wilson <[email protected]> Reviewed-by: Andi Shyti <[email protected]> --- drivers/gpu/drm/i915/gt/intel_breadcrumbs.c | 10 +++++----- drivers/gpu/drm/i915/gt/intel_execlists_submission.c | 2 +- drivers/gpu/drm/i915/gt/intel_timeline.h | 7 +++++++ 3 files changed, 13 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c index 7137b6f24f55..be2c285a0ac7 100644 --- a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c +++ b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c @@ -257,17 +257,17 @@ static void signal_irq_work(struct irq_work *work) list_del_rcu(&rq->signal_link); release = remove_signaling_context(b, ce); spin_unlock(&ce->signal_lock); + if (release) { + if (intel_timeline_is_last(ce->timeline, rq)) + add_retire(b, ce->timeline); + intel_context_put(ce); + } if (__dma_fence_signal(&rq->fence)) /* We own signal_node now, xfer to local list */ signal = slist_add(&rq->signal_node, signal); else i915_request_put(rq); - - if (release) { - add_retire(b, ce->timeline); - intel_context_put(ce); - } } } atomic_dec(&b->signaler_active); diff --git a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c index eb69eef9d7db..aadd04f8dc9e 100644 --- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c +++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c @@ -640,7 +640,7 @@ static inline void __execlists_schedule_out(struct i915_request *rq) * If we have just completed this context, the engine may now be * idle and we want to re-enter powersaving. */ - if (list_is_last_rcu(&rq->link, &ce->timeline->requests) && + if (intel_timeline_is_last(ce->timeline, rq) && __i915_request_is_complete(rq)) intel_engine_add_retire(engine, ce->timeline); diff --git a/drivers/gpu/drm/i915/gt/intel_timeline.h b/drivers/gpu/drm/i915/gt/intel_timeline.h index f502a619843f..dcdee692a80e 100644 --- a/drivers/gpu/drm/i915/gt/intel_timeline.h +++ b/drivers/gpu/drm/i915/gt/intel_timeline.h @@ -110,4 +110,11 @@ void intel_gt_show_timelines(struct intel_gt *gt, const char *prefix, int indent)); +static inline bool +intel_timeline_is_last(const struct intel_timeline *tl, + const struct i915_request *rq) +{ + return list_is_last_rcu(&rq->link, &tl->requests); +} + #endif -- 2.20.1 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
