st/dri: implement the fence interface

diff --git a/src/gallium/state_trackers/dri/dri2.c b/src/gallium/state_trackers/dri/dri2.c
index f8f4ecf36d77e4764aefe8d00f2db634652e8489..9b5631326d436e2576e2c85e2b8c74e0a5ae5aa4 100644 (file)
--- a/src/gallium/state_trackers/dri/dri2.c
+++ b/src/gallium/state_trackers/dri/dri2.c
@@ -1251,6 +1251,85 @@ static __DRIimageExtension dri2ImageExtension = {
     .getCapabilities              = dri2_get_capabilities,
 };
 
+
+struct dri2_fence {
+   struct pipe_fence_handle *pipe_fence;
+};
+
+static void *
+dri2_create_fence(__DRIcontext *_ctx)
+{
+   struct pipe_context *ctx = dri_context(_ctx)->st->pipe;
+   struct dri2_fence *fence = CALLOC_STRUCT(dri2_fence);
+
+   if (!fence)
+      return NULL;
+
+   ctx->flush(ctx, &fence->pipe_fence, 0);
+
+   if (!fence->pipe_fence) {
+      FREE(fence);
+      return NULL;
+   }
+
+   return fence;
+}
+
+static void *
+dri2_get_fence_from_cl_event(__DRIscreen *_screen, intptr_t cl_event)
+{
+   return NULL;
+}
+
+static void
+dri2_destroy_fence(__DRIscreen *_screen, void *_fence)
+{
+   struct dri_screen *driscreen = dri_screen(_screen);
+   struct pipe_screen *screen = driscreen->base.screen;
+   struct dri2_fence *fence = (struct dri2_fence*)_fence;
+
+   if (fence->pipe_fence)
+      screen->fence_reference(screen, &fence->pipe_fence, NULL);
+   else
+      assert(0);
+
+   FREE(fence);
+}
+
+static GLboolean
+dri2_client_wait_sync(__DRIcontext *_ctx, void *_fence, unsigned flags,
+                      uint64_t timeout)
+{
+   struct dri_screen *driscreen = dri_screen(_ctx->driScreenPriv);
+   struct pipe_screen *screen = driscreen->base.screen;
+   struct dri2_fence *fence = (struct dri2_fence*)_fence;
+
+   /* No need to flush. The context was flushed when the fence was created. */
+
+   if (fence->pipe_fence)
+      return screen->fence_finish(screen, fence->pipe_fence, timeout);
+   else {
+      assert(0);
+      return false;
+   }
+}
+
+static void
+dri2_server_wait_sync(__DRIcontext *_ctx, void *_fence, unsigned flags)
+{
+   /* AFAIK, no driver currently supports parallel context execution. */
+}
+
+static __DRI2fenceExtension dri2FenceExtension = {
+   .base = { __DRI2_FENCE, 1 },
+
+   .create_fence = dri2_create_fence,
+   .get_fence_from_cl_event = dri2_get_fence_from_cl_event,
+   .destroy_fence = dri2_destroy_fence,
+   .client_wait_sync = dri2_client_wait_sync,
+   .server_wait_sync = dri2_server_wait_sync
+};
+
 /*
  * Backend function init_screen.
  */
@@ -1262,6 +1341,7 @@ static const __DRIextension *dri_screen_extensions[] = {
    &dri2RendererQueryExtension.base,
    &dri2ConfigQueryExtension.base,
    &dri2ThrottleExtension.base,
+   &dri2FenceExtension.base,
    NULL
 };