+ /* Make sure tcp's tx fifo can actually buffer all bytes to be dequeued.
+ * If under memory pressure, tls's fifo segment might not be able to
+ * allocate the chunks needed. This also avoids errors from the underlying
+ * custom bio to the ssl infra which at times can get stuck. */
+ if (svm_fifo_provision_chunks (ts->tx_fifo, 0, 0, deq_max + TLSO_CTRL_BYTES))
+ goto check_tls_fifo;
+