If a syncobj has not yet been assigned, treat it as a future fence and install and wait upon a dma-fence-proxy. The proxy will be replace by the real fence later, and that fence will be responsible for signaling our waiter.
Link: https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4854 Signed-off-by: Chris Wilson <[email protected]> --- .../gpu/drm/i915/gem/i915_gem_execbuffer.c | 20 +++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c index 2844274c37bb..4fddbe34efa6 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c @@ -2490,8 +2490,24 @@ await_fence_array(struct i915_execbuffer *eb, continue; fence = drm_syncobj_fence_get(syncobj); - if (!fence) - return -EINVAL; + if (!fence) { + struct dma_fence *old; + + fence = dma_fence_create_proxy(); + if (!fence) + return -ENOMEM; + + spin_lock(&syncobj->lock); + old = rcu_dereference_protected(syncobj->fence, true); + if (unlikely(old)) { + dma_fence_put(fence); + fence = dma_fence_get(old); + } else { + rcu_assign_pointer(syncobj->fence, + dma_fence_get(fence)); + } + spin_unlock(&syncobj->lock); + } err = i915_request_await_dma_fence(eb->request, fence); dma_fence_put(fence); -- 2.20.1 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
