drm/i915/gt: Add breadcrumb retire to physical engine

Avoid adding the retire workers to the virtual engine so that we don't
end up in the unenviable situation of trying to free the virtual engine
while its worker remains active.

Fixes: dc93c9b6 ("drm/i915/gt: Schedule request retirement when signaler idles")
Closes: https://gitlab.freedesktop.org/drm/intel/issues/867Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191219221344.161523-1-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/gt/intel_breadcrumbs.c

@@ -131,6 +131,14 @@ __dma_fence_signal__notify(struct dma_fence *fence,
 	}
 }
 
+static void add_retire(struct intel_breadcrumbs *b, struct intel_timeline *tl)
+{
+	struct intel_engine_cs *engine =
+		container_of(b, struct intel_engine_cs, breadcrumbs);
+
+	intel_engine_add_retire(engine, tl);
+}
+
 static void signal_irq_work(struct irq_work *work)
 {
 	struct intel_breadcrumbs *b = container_of(work, typeof(*b), irq_work);
@@ -182,8 +190,7 @@ static void signal_irq_work(struct irq_work *work)
 			__list_del_many(&ce->signals, pos);
 			if (&ce->signals == pos) { /* now empty */
 				list_del_init(&ce->signal_link);
-				intel_engine_add_retire(ce->engine,
-							ce->timeline);
+				add_retire(b, ce->timeline);
 			}
 		}
 	}

drivers/gpu/drm/i915/gt/intel_lrc.c

@@ -4512,7 +4512,6 @@ intel_execlists_create_virtual(struct i915_gem_context *ctx,
 	intel_engine_init_active(&ve->base, ENGINE_VIRTUAL);
 	intel_engine_init_breadcrumbs(&ve->base);
 	intel_engine_init_execlists(&ve->base);
-	intel_engine_init_retire(&ve->base);
 
 	ve->base.cops = &virtual_context_ops;
 	ve->base.request_alloc = execlists_request_alloc;