drm/i915: Markup expected timeline locks for i915_active

As every i915_active_request should be serialised by a dedicated lock,
i915_active consists of a tree of locks; one for each node. Markup up
the i915_active_request with what lock is supposed to be guarding it so
that we can verify that the serialised updated are indeed serialised.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190816121000.8507-2-chris@chris-wilson.co.uk

5 files changed, 12 insertions, 14 deletions

diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c
index 9114953bf920..f55691d151ae 100644
--- a/drivers/gpu/drm/i915/gt/intel_context.c
+++ b/drivers/gpu/drm/i915/gt/intel_context.c
@@ -306,10 +306,10 @@ int intel_context_prepare_remote_request(struct intel_context *ce,
 
 		/* Queue this switch after current activity by this context. */
 		err = i915_active_request_set(&tl->last_request, rq);
+		mutex_unlock(&tl->mutex);
 		if (err)
-			goto unlock;
+			return err;
 	}
-	lockdep_assert_held(&tl->mutex);
 
 	/*
 	 * Guarantee context image and the timeline remains pinned until the
@@ -319,12 +319,7 @@ int intel_context_prepare_remote_request(struct intel_context *ce,
 	 * words transfer the pinned ce object to tracked active request.
 	 */
 	GEM_BUG_ON(i915_active_is_idle(&ce->active));
-	err = i915_active_ref(&ce->active, rq->fence.context, rq);
-
-unlock:
-	if (rq->timeline != tl)
-		mutex_unlock(&tl->mutex);
-	return err;
+	return i915_active_ref(&ce->active, rq->timeline, rq);
 }
 
 struct i915_request *intel_context_create_request(struct intel_context *ce)
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_pool.h b/drivers/gpu/drm/i915/gt/intel_engine_pool.h
index f7a0a660c1c9..8d069efd9457 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_pool.h
+++ b/drivers/gpu/drm/i915/gt/intel_engine_pool.h
@@ -18,7 +18,7 @@ static inline int
 intel_engine_pool_mark_active(struct intel_engine_pool_node *node,
 			      struct i915_request *rq)
 {
-	return i915_active_ref(&node->active, rq->fence.context, rq);
+	return i915_active_ref(&node->active, rq->timeline, rq);
 }
 
 static inline void
diff --git a/drivers/gpu/drm/i915/gt/intel_timeline.c b/drivers/gpu/drm/i915/gt/intel_timeline.c
index eafd94d5e211..02fbe11b671b 100644
--- a/drivers/gpu/drm/i915/gt/intel_timeline.c
+++ b/drivers/gpu/drm/i915/gt/intel_timeline.c
@@ -254,7 +254,7 @@ int intel_timeline_init(struct intel_timeline *timeline,
 
 	mutex_init(&timeline->mutex);
 
-	INIT_ACTIVE_REQUEST(&timeline->last_request);
+	INIT_ACTIVE_REQUEST(&timeline->last_request, &timeline->mutex);
 	INIT_LIST_HEAD(&timeline->requests);
 
 	i915_syncmap_init(&timeline->sync);
@@ -440,8 +440,7 @@ __intel_timeline_get_seqno(struct intel_timeline *tl,
 	 * free it after the current request is retired, which ensures that
 	 * all writes into the cacheline from previous requests are complete.
 	 */
-	err = i915_active_ref(&tl->hwsp_cacheline->active,
-			      tl->fence_context, rq);
+	err = i915_active_ref(&tl->hwsp_cacheline->active, tl, rq);
 	if (err)
 		goto err_cacheline;
 
@@ -492,7 +491,7 @@ int intel_timeline_get_seqno(struct intel_timeline *tl,
 static int cacheline_ref(struct intel_timeline_cacheline *cl,
 			 struct i915_request *rq)
 {
-	return i915_active_ref(&cl->active, rq->fence.context, rq);
+	return i915_active_ref(&cl->active, rq->timeline, rq);
 }
 
 int intel_timeline_read_hwsp(struct i915_request *from,
diff --git a/drivers/gpu/drm/i915/gt/selftest_timeline.c b/drivers/gpu/drm/i915/gt/selftest_timeline.c
index d54113697745..321481403165 100644
--- a/drivers/gpu/drm/i915/gt/selftest_timeline.c
+++ b/drivers/gpu/drm/i915/gt/selftest_timeline.c
@@ -689,7 +689,9 @@ static int live_hwsp_wrap(void *arg)
 
 		tl->seqno = -4u;
 
+		mutex_lock_nested(&tl->mutex, SINGLE_DEPTH_NESTING);
 		err = intel_timeline_get_seqno(tl, rq, &seqno[0]);
+		mutex_unlock(&tl->mutex);
 		if (err) {
 			i915_request_add(rq);
 			goto out;
@@ -704,7 +706,9 @@ static int live_hwsp_wrap(void *arg)
 		}
 		hwsp_seqno[0] = tl->hwsp_seqno;
 
+		mutex_lock_nested(&tl->mutex, SINGLE_DEPTH_NESTING);
 		err = intel_timeline_get_seqno(tl, rq, &seqno[1]);
+		mutex_unlock(&tl->mutex);
 		if (err) {
 			i915_request_add(rq);
 			goto out;
diff --git a/drivers/gpu/drm/i915/gt/selftests/mock_timeline.c b/drivers/gpu/drm/i915/gt/selftests/mock_timeline.c
index 5c549205828a..598170efcaf6 100644
--- a/drivers/gpu/drm/i915/gt/selftests/mock_timeline.c
+++ b/drivers/gpu/drm/i915/gt/selftests/mock_timeline.c
@@ -15,7 +15,7 @@ void mock_timeline_init(struct intel_timeline *timeline, u64 context)
 
 	mutex_init(&timeline->mutex);
 
-	INIT_ACTIVE_REQUEST(&timeline->last_request);
+	INIT_ACTIVE_REQUEST(&timeline->last_request, &timeline->mutex);
 	INIT_LIST_HEAD(&timeline->requests);
 
 	i915_syncmap_init(&timeline->sync);