[RFC v2 04/15] drm/amdgpu: introduce a flag to track refcount held for features

[Jiang Liu <gerry@linux.alibaba.com>]

Currently we track the refcount on ras block object for features by
checking `if (obj && amdgpu_ras_is_feature_enabled(adev, head))`,
which is a little unreliable. So introduce a dedicated flag to track
the reference count.

Signed-off-by: Jiang Liu <gerry@linux.alibaba.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu.h     | 1 +
 drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c | 9 +++++++--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index 09b63a622728..24ef39b706e3 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -380,6 +380,7 @@ int amdgpu_ip_block_resume(struct amdgpu_ip_block *ip_block);
 enum amdgpu_marker {
 	// Markers for ras blocks.
 	AMDGPU_MARKER_RAS_DEBUGFS,
+	AMDGPU_MARKER_RAS_FEATURE,
 	// Markers for IRQs, used for both ip blocks and ras blocks.
 	AMDGPU_MARKER_IRQ0 = 32,
 	AMDGPU_MARKER_IRQ1,
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c
index 6b508a9b1abe..f0cd14ff78a7 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c
@@ -775,15 +775,20 @@ static int __amdgpu_ras_feature_enable(struct amdgpu_device *adev,
 			obj = amdgpu_ras_create_obj(adev, head);
 			if (!obj)
 				return -EINVAL;
-		} else {
+			amdgpu_ras_set_marker(adev, head, AMDGPU_MARKER_RAS_FEATURE);
+		} else if (!amdgpu_ras_test_marker(adev, head,
+						   AMDGPU_MARKER_RAS_FEATURE)) {
 			/* In case we create obj somewhere else */
 			get_obj(obj);
+			amdgpu_ras_set_marker(adev, head, AMDGPU_MARKER_RAS_FEATURE);
 		}
 		con->features |= BIT(head->block);
 	} else {
 		if (obj && amdgpu_ras_is_feature_enabled(adev, head)) {
 			con->features &= ~BIT(head->block);
-			put_obj(obj);
+			if (amdgpu_ras_test_and_clear_marker(adev, head,
+							     AMDGPU_MARKER_RAS_FEATURE))
+				put_obj(obj);
 		}
 	}
 
-- 
2.43.5