if (G_UNLIKELY (bclass->remove_element == NULL))
goto no_function;
+ /* We need to take the state lock here to ensure that we're
+ * not currently just before setting the state of this child
+ * element. Otherwise it can happen that we removed the element
+ * here and e.g. set it to NULL state, and shortly afterwards
+ * have another thread set it to a higher state again as part of
+ * a state change for the whole bin.
+ *
+ * When adding an element to the bin this is not needed as we
+ * require callers to always ensure after adding to the bin that
+ * the new element is set to the correct state.
+ */
+ GST_STATE_LOCK (bin);
+
GST_CAT_DEBUG (GST_CAT_PARENTAGE, "removing element %s from bin %s",
GST_ELEMENT_NAME (element), GST_ELEMENT_NAME (bin));
result = bclass->remove_element (bin, element);
GST_TRACER_BIN_REMOVE_POST (bin, result);
+ GST_STATE_UNLOCK (bin);
+
return result;
/* ERROR handling */