mesa: add default function for ctx->Driver.CheckQuery() hook

src/mesa/drivers/common/driverfuncs.c

@@ -231,6 +231,7 @@ _mesa_init_driver_functions(struct dd_function_table *driver)
    driver->BeginQuery = _mesa_begin_query;
    driver->EndQuery = _mesa_end_query;
    driver->WaitQuery = _mesa_wait_query;
+   driver->CheckQuery = _mesa_check_query;
 
    /* APPLE_vertex_array_object */
    driver->NewArrayObject = _mesa_new_array_object;

src/mesa/main/queryobj.c

@@ -83,12 +83,26 @@ void
 _mesa_wait_query(GLcontext *ctx, struct gl_query_object *q)
 {
    /* For software drivers, _mesa_end_query() should have completed the query.
-    * For real hardware, implement a proper WaitQuery() driver function.
+    * For real hardware, implement a proper WaitQuery() driver function,
+    * which may require issuing a flush.
     */
    assert(q->Ready);
 }
 
 
+/**
+ * Check if a query results are ready.  Software driver fallback.
+ * Called via ctx->Driver.CheckQuery().
+ */
+void
+_mesa_check_query(GLcontext *ctx, struct gl_query_object *q)
+{
+   /* No-op for sw rendering.
+    * HW drivers may need to flush at this time.
+    */
+}
+
+
 /**
  * Delete a query object.  Called via ctx->Driver.DeleteQuery().
  * Not removed from hash table here.

src/mesa/main/queryobj.h

@@ -48,6 +48,9 @@ _mesa_end_query(GLcontext *ctx, struct gl_query_object *q);
 extern void
 _mesa_wait_query(GLcontext *ctx, struct gl_query_object *q);
 
+extern void
+_mesa_check_query(GLcontext *ctx, struct gl_query_object *q);
+
 
 extern void GLAPIENTRY
 _mesa_GenQueriesARB(GLsizei n, GLuint *ids);