[Intel-gfx] [PATCH 3/3] drm/i915/gt: Mark ring->vma as active while pinned

[Chris Wilson]

As we use the active state to keep the vma alive while we are reading
its contents during GPU error capture, we need to mark the
ring->vma as active during execution if we want to include the rinbuffer
in the error state.

Reported-by: Lionel Landwerlin <lionel.g.landwerlin at intel.com>
Fixes: b1e3177bd1d8 ("drm/i915: Coordinate i915_active with its own mutex")
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
Cc: Lionel Landwerlin <lionel.g.landwerlin at intel.com>
Acked-by: Lionel Landwerlin <lionel.g.landwerlin at intel.com>
---
 drivers/gpu/drm/i915/gt/intel_context.c | 31 ++++++++++++++++++++++---
 1 file changed, 28 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c
index 8774c18f405e..23137b2a8689 100644
--- a/drivers/gpu/drm/i915/gt/intel_context.c
+++ b/drivers/gpu/drm/i915/gt/intel_context.c
@@ -185,6 +185,31 @@ static void __context_unpin_state(struct i915_vma *vma)
 	__i915_vma_unpin(vma);
 }
 
+static int __ring_active(struct intel_ring *ring)
+{
+	int err;
+
+	err = i915_active_acquire(&ring->vma->active);
+	if (err)
+		return err;
+
+	err = intel_ring_pin(ring);
+	if (err)
+		goto err_active;
+
+	return 0;
+
+err_active:
+	i915_active_release(&ring->vma->active);
+	return err;
+}
+
+static void __ring_retire(struct intel_ring *ring)
+{
+	intel_ring_unpin(ring);
+	i915_active_release(&ring->vma->active);
+}
+
 __i915_active_call
 static void __intel_context_retire(struct i915_active *active)
 {
@@ -197,7 +222,7 @@ static void __intel_context_retire(struct i915_active *active)
 		__context_unpin_state(ce->state);
 
 	intel_timeline_unpin(ce->timeline);
-	intel_ring_unpin(ce->ring);
+	__ring_retire(ce->ring);
 
 	intel_context_put(ce);
 }
@@ -211,7 +236,7 @@ static int __intel_context_active(struct i915_active *active)
 
 	intel_context_get(ce);
 
-	err = intel_ring_pin(ce->ring);
+	err = __ring_active(ce->ring);
 	if (err)
 		goto err_put;
 
@@ -231,7 +256,7 @@ static int __intel_context_active(struct i915_active *active)
 err_timeline:
 	intel_timeline_unpin(ce->timeline);
 err_ring:
-	intel_ring_unpin(ce->ring);
+	__ring_retire(ce->ring);
 err_put:
 	intel_context_put(ce);
 	return err;
-- 
2.25.0.rc2