[Intel-gfx] [PATCH 17/57] drm/i915: Extract request suspension from the execlists

[Tvrtko Ursulin]

On 02/02/2021 13:26, Chris Wilson wrote:
> Quoting Tvrtko Ursulin (2021-02-02 13:15:52)
>>
>> On 01/02/2021 08:56, Chris Wilson wrote:
>>> +void __i915_sched_resume_request(struct intel_engine_cs *engine,
>>> +                              struct i915_request *rq)
>>> +{
>>> +     LIST_HEAD(list);
>>> +
>>> +     lockdep_assert_held(&engine->active.lock);
>>> +
>>> +     if (rq_prio(rq) > engine->execlists.queue_priority_hint) {
>>> +             engine->execlists.queue_priority_hint = rq_prio(rq);
>>> +             tasklet_hi_schedule(&engine->execlists.tasklet);
>>> +     }
>>> +
>>> +     if (!i915_request_on_hold(rq))
>>> +             return;
>>> +
>>> +     ENGINE_TRACE(engine, "resuming request %llx:%lld\n",
>>> +                  rq->fence.context, rq->fence.seqno);
>>> +
>>> +     /*
>>> +      * Move this request back to the priority queue, and all of its
>>> +      * children and grandchildren that were suspended along with it.
>>> +      */
>>> +     do {
>>> +             struct i915_dependency *p;
>>> +
>>> +             RQ_TRACE(rq, "hold release\n");
>>> +
>>> +             GEM_BUG_ON(!i915_request_on_hold(rq));
>>> +             GEM_BUG_ON(!i915_sw_fence_signaled(&rq->submit));
>>> +
>>> +             i915_request_clear_hold(rq);
>>> +             list_del_init(&rq->sched.link);
>>> +
>>> +             queue_request(engine, rq);
>>> +
>>> +             /* Also release any children on this engine that are ready */
>>> +             for_each_waiter(p, rq) {
>>> +                     struct i915_request *w =
>>> +                             container_of(p->waiter, typeof(*w), sched);
>>> +
>>> +                     if (p->flags & I915_DEPENDENCY_WEAK)
>>> +                             continue;
>>> +
>>> +                     /* Propagate any change in error status */
>>> +                     if (rq->fence.error)
>>> +                             i915_request_set_error_once(w, rq->fence.error);
>>> +
>>> +                     if (w->engine != engine)
>>> +                             continue;
>>> +
>>> +                     /* We also treat the on-hold status as a visited bit */
>>> +                     if (!i915_request_on_hold(w))
>>> +                             continue;
>>> +
>>> +                     /* Check that no other parents are also on hold [BFS] */
>>> +                     if (hold_request(w))
>>> +                             continue;
>>
>> hold_request() appears deleted in the patch so possible rebase error.
> 
> The secret is we get to de-duplicate after having duplicated
> hold_request() in i915_scheduler in an earlier patch,
>    drm/i915: Extract request submission from execlists

Pfft ancient history long forgotten..

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>

Regards,

Tvrtko