From 89b6d1831d21554a5737a201b78a6ad6c5517b46 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Sun, 13 Oct 2019 21:30:12 +0100
Subject: drm/i915/execlists: Tweak virtual unsubmission
Git-commit: 89b6d1831d21554a5737a201b78a6ad6c5517b46
Patch-mainline: v5.5-rc1
References: bsc#1152489

Since commit e2144503bf3b ("drm/i915: Prevent bonded requests from
overtaking each other on preemption") we have restricted requests to run
on their chosen engine across preemption events. We can take this
restriction into account to know that we will want to resubmit those
requests onto the same physical engine, and so can shortcircuit the
virtual engine selection process and keep the request on the same
engine during unwind.

References: e2144503bf3b ("drm/i915: Prevent bonded requests from overtaking each other on preemption")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Ramlingam C <ramalingam.c@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191013203012.25208-1-chris@chris-wilson.co.uk
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/i915/gt/intel_lrc.c | 6 +++---
 drivers/gpu/drm/i915/i915_request.c | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index a07baeb897fe..ee21307ab5fe 100644
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -847,7 +847,6 @@ __unwind_incomplete_requests(struct intel_engine_cs *engine)
 	list_for_each_entry_safe_reverse(rq, rn,
 					 &engine->active.requests,
 					 sched.link) {
-		struct intel_engine_cs *owner;
 
 		if (i915_request_completed(rq))
 			continue; /* XXX */
@@ -862,8 +861,7 @@ __unwind_incomplete_requests(struct intel_engine_cs *engine)
 		 * engine so that it can be moved across onto another physical
 		 * engine as load dictates.
 		 */
-		owner = rq->hw_context->engine;
-		if (likely(owner == engine)) {
+		if (likely(rq->execution_mask == engine->mask)) {
 			GEM_BUG_ON(rq_prio(rq) == I915_PRIORITY_INVALID);
 			if (rq_prio(rq) != prio) {
 				prio = rq_prio(rq);
@@ -874,6 +872,8 @@ __unwind_incomplete_requests(struct intel_engine_cs *engine)
 			list_move(&rq->sched.link, pl);
 			active = rq;
 		} else {
+			struct intel_engine_cs *owner = rq->hw_context->engine;
+
 			/*
 			 * Decouple the virtual breadcrumb before moving it
 			 * back to the virtual engine -- we don't want the
diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index 437f9fc6282e..b8a54572a4f8 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -649,6 +649,7 @@ __i915_request_create(struct intel_context *ce, gfp_t gfp)
 	rq->gem_context = ce->gem_context;
 	rq->engine = ce->engine;
 	rq->ring = ce->ring;
+	rq->execution_mask = ce->engine->mask;
 
 	rcu_assign_pointer(rq->timeline, tl);
 	rq->hwsp_seqno = tl->hwsp_seqno;
@@ -671,7 +672,6 @@ __i915_request_create(struct intel_context *ce, gfp_t gfp)
 	rq->batch = NULL;
 	rq->capture_list = NULL;
 	rq->flags = 0;
-	rq->execution_mask = ALL_ENGINES;
 
 	INIT_LIST_HEAD(&rq->execute_cb);
 
-- 
2.28.0