[PATCH v2 3/3] drm/amdgpu: validate the eviction fence before attaching/detaching

[Prike Liang]

Before the user queue BOs resume workqueue is scheduled;
there's no valid eviction fence to attach the gem obj.
For this case, it doesn't need to attach/detach the eviction
fence. Also, it needs to unlock the bo first before returning
from the eviction fence attached error.

Signed-off-by: Prike Liang <Prike.Liang at amd.com>
---
 .../gpu/drm/amd/amdgpu/amdgpu_eviction_fence.c   |  3 +++
 drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c          | 16 ++++++++++------
 2 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_eviction_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_eviction_fence.c
index 7a5f02ef45a7..aa9f523e62c0 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_eviction_fence.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_eviction_fence.c
@@ -216,6 +216,9 @@ void amdgpu_eviction_fence_detach(struct amdgpu_eviction_fence_mgr *evf_mgr,
 {
 	struct dma_fence *stub = dma_fence_get_stub();
 
+	if (dma_fence_is_signaled(&evf_mgr->ev_fence->base))
+		return;
+
 	dma_resv_replace_fences(bo->tbo.base.resv, evf_mgr->ev_fence_ctx,
 				stub, DMA_RESV_USAGE_BOOKKEEP);
 	dma_fence_put(stub);
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
index f03fc3cf4d50..11d4a9af7bc5 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
@@ -294,11 +294,14 @@ static int amdgpu_gem_object_open(struct drm_gem_object *obj,
 	else
 		++bo_va->ref_count;
 
-	/* attach gfx eviction fence */
-	r = amdgpu_eviction_fence_attach(&fpriv->evf_mgr, abo);
-	if (r) {
-		DRM_DEBUG_DRIVER("Failed to attach eviction fence to BO\n");
-		return r;
+	/* attach gfx the validated eviction fence */
+	if (!IS_ERR_OR_NULL(fpriv->evf_mgr.ev_fence)) {
+		r = amdgpu_eviction_fence_attach(&fpriv->evf_mgr, abo);
+		if (r) {
+			DRM_DEBUG_DRIVER("Failed to attach eviction fence to BO\n");
+			amdgpu_bo_unreserve(abo);
+			return r;
+		}
 	}
 
 	amdgpu_bo_unreserve(abo);
@@ -364,7 +367,8 @@ static void amdgpu_gem_object_close(struct drm_gem_object *obj,
 			goto out_unlock;
 	}
 
-	if (!amdgpu_vm_is_bo_always_valid(vm, bo))
+	if (!amdgpu_vm_is_bo_always_valid(vm, bo) &&
+			!IS_ERR_OR_NULL(fpriv->evf_mgr.ev_fence))
 		amdgpu_eviction_fence_detach(&fpriv->evf_mgr, bo);
 
 	bo_va = amdgpu_vm_bo_find(vm, bo);
-- 
2.34.1