drm/amdgpu: mitigate workaround for i915

To be able to use DRI_PRIME with amdgpu and i915 we add all our fences
only as exclusive ones.

Disable that behavior when sharing between amdgpu itself cause it
hinders concurrent execution.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c
index f6d7f64..8ce74a1 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c
@@ -30,6 +30,8 @@
 #include <drm/amdgpu_drm.h>
 #include <linux/dma-buf.h>
 
+static const struct dma_buf_ops amdgpu_dmabuf_ops;
+
 struct sg_table *amdgpu_gem_prime_get_sg_table(struct drm_gem_object *obj)
 {
        struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
@@ -129,20 +131,27 @@ static int amdgpu_gem_map_attach(struct dma_buf *dma_buf,
        if (unlikely(r != 0))
                goto error_detach;
 
-       /*
-        * Wait for all shared fences to complete before we switch to future
-        * use of exclusive fence on this prime shared bo.
-        */
-       r = reservation_object_wait_timeout_rcu(bo->tbo.resv, true, false,
-                                               MAX_SCHEDULE_TIMEOUT);
-       if (unlikely(r < 0)) {
-               DRM_DEBUG_PRIME("Fence wait failed: %li\n", r);
-               goto error_unreserve;
+
+       if (dma_buf->ops != &amdgpu_dmabuf_ops) {
+               /*
+                * Wait for all shared fences to complete before we switch to future
+                * use of exclusive fence on this prime shared bo.
+                */
+               r = reservation_object_wait_timeout_rcu(bo->tbo.resv,
+                                                       true, false,
+                                                       MAX_SCHEDULE_TIMEOUT);
+               if (unlikely(r < 0)) {
+                       DRM_DEBUG_PRIME("Fence wait failed: %li\n", r);
+                       goto error_unreserve;
+               }
        }
 
        /* pin buffer into GTT */
        r = amdgpu_bo_pin(bo, AMDGPU_GEM_DOMAIN_GTT, NULL);
-       if (likely(r == 0))
+       if (r)
+               goto error_unreserve;
+
+       if (dma_buf->ops != &amdgpu_dmabuf_ops)
                bo->prime_shared_count++;
 
 error_unreserve:
@@ -166,7 +175,7 @@ static void amdgpu_gem_map_detach(struct dma_buf *dma_buf,
                goto error;
 
        amdgpu_bo_unpin(bo);
-       if (bo->prime_shared_count)
+       if (dma_buf->ops != &amdgpu_dmabuf_ops && bo->prime_shared_count)
                bo->prime_shared_count--;
        amdgpu_bo_unreserve(bo);