vcl: fix empty epoll returns (VPP-1453)

[vpp.git] / src / vcl / vppcom.c

diff --git a/src/vcl/vppcom.c b/src/vcl/vppcom.c
index 5423bb6..df4ebde 100644 (file)
--- a/src/vcl/vppcom.c
+++ b/src/vcl/vppcom.c
@@ -1332,12 +1332,11 @@ vppcom_session_read_internal (uint32_t session_handle, void *buf, int n,
   if (svm_fifo_is_empty (rx_fifo))
     svm_fifo_unset_event (rx_fifo);
 
-  if (is_ct && n_read + svm_fifo_max_dequeue (rx_fifo) == rx_fifo->nitems)
+  if (is_ct && svm_fifo_want_tx_evt (rx_fifo))
     {
-      /* If the peer is not polling send notification */
-      if (!svm_fifo_has_event (s->rx_fifo))
-       app_send_io_evt_to_vpp (s->vpp_evt_q, s->rx_fifo,
-                               SESSION_IO_EVT_CT_RX, SVM_Q_WAIT);
+      svm_fifo_set_want_tx_evt (s->rx_fifo, 0);
+      app_send_io_evt_to_vpp (s->vpp_evt_q, s->rx_fifo, SESSION_IO_EVT_CT_RX,
+                             SVM_Q_WAIT);
     }
 
   VDBG (2, "VCL<%d>: vpp handle 0x%llx, sid %u: read %d bytes from (%p)",
@@ -2509,6 +2508,7 @@ vppcom_epoll_wait_eventfd (vcl_worker_t * wrk, struct epoll_event *events,
   u64 buf;
 
   vec_validate (wrk->mq_events, pool_elts (wrk->mq_evt_conns));
+again:
   n_mq_evts = epoll_wait (wrk->mqs_epfd, wrk->mq_events,
                          vec_len (wrk->mq_events), wait_for_time);
   for (i = 0; i < n_mq_evts; i++)
@@ -2517,6 +2517,8 @@ vppcom_epoll_wait_eventfd (vcl_worker_t * wrk, struct epoll_event *events,
       n_read = read (mqc->mq_fd, &buf, sizeof (buf));
       vcl_epoll_wait_handle_mq (wrk, mqc->mq, events, maxevents, 0, &n_evts);
     }
+  if (!n_evts && n_mq_evts > 0)
+    goto again;
 
   return (int) n_evts;
 }