vcl: fix epoll ctl frequent deq ntf requests

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

diff --git a/src/vcl/vppcom.c b/src/vcl/vppcom.c
index ecbbf7a..f2166f8 100644 (file)
--- a/src/vcl/vppcom.c
+++ b/src/vcl/vppcom.c
@@ -2421,12 +2421,8 @@ vcl_select_handle_mq_event (vcl_worker_t * wrk, session_event_t * e,
       clib_bitmap_set_no_check ((uword *) write_map, sid, 1);
       *bits_set += 1;
       s = vcl_session_get (wrk, sid);
-      if (!s->tx_fifo)
-       break;
       /* We didn't have a fifo when the event was added */
-      svm_fifo_add_want_deq_ntf (
-       (vcl_session_is_ct (s) ? s->ct_tx_fifo : s->tx_fifo),
-       SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL);
+      vcl_session_add_want_deq_ntf (s, SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL);
       break;
     case SESSION_CTRL_EVT_DISCONNECTED:
       disconnected_msg = (session_disconnected_msg_t *) e->data;
@@ -2636,10 +2632,9 @@ vppcom_select (int n_bits, vcl_si_set * read_map, vcl_si_set * write_map,
          clib_bitmap_set_no_check ((uword *) write_map, sid, 1);
          bits_set++;
        }
-      else if (s->tx_fifo)
+      else
        {
-         svm_fifo_t *txf = vcl_session_is_ct (s) ? s->ct_tx_fifo : s->tx_fifo;
-         svm_fifo_add_want_deq_ntf (txf, SVM_FIFO_WANT_DEQ_NOTIF);
+         vcl_session_add_want_deq_ntf (s, SVM_FIFO_WANT_DEQ_NOTIF);
        }
     }
 
@@ -2801,7 +2796,6 @@ vppcom_epoll_ctl (uint32_t vep_handle, int op, uint32_t session_handle,
   int rv = VPPCOM_OK, add_evt = 0;
   vcl_session_t *vep_session;
   vcl_session_t *s;
-  svm_fifo_t *txf;
 
   if (vep_handle == session_handle)
     {
@@ -2874,16 +2868,22 @@ vppcom_epoll_ctl (uint32_t vep_handle, int op, uint32_t session_handle,
       s->flags |= VCL_SESSION_F_IS_VEP_SESSION;
       vep_session->vep.next_sh = session_handle;
 
-      txf = vcl_session_is_ct (s) ? s->ct_tx_fifo : s->tx_fifo;
-      if (txf && (event->events & EPOLLOUT))
-       svm_fifo_add_want_deq_ntf (txf, SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL);
-
-      /* Generate EPOLLOUT if tx fifo not full */
-      if ((event->events & EPOLLOUT) && (vcl_session_write_ready (s) > 0))
+      if ((event->events & EPOLLOUT))
        {
-         vcl_epoll_ctl_add_unhandled_event (wrk, s, event->events & EPOLLET,
-                                            SESSION_IO_EVT_TX);
-         add_evt = 1;
+         int write_ready = vcl_session_write_ready (s);
+
+         vcl_session_add_want_deq_ntf (s, SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL);
+         if (write_ready > 0)
+           {
+             /* Generate EPOLLOUT if tx fifo not full */
+             vcl_epoll_ctl_add_unhandled_event (
+               wrk, s, event->events & EPOLLET, SESSION_IO_EVT_TX);
+             add_evt = 1;
+           }
+         else
+           {
+             vcl_session_add_want_deq_ntf (s, SVM_FIFO_WANT_DEQ_NOTIF);
+           }
        }
       /* Generate EPOLLIN if rx fifo has data */
       if ((event->events & EPOLLIN) && (vcl_session_read_ready (s) > 0))
@@ -2929,22 +2929,23 @@ vppcom_epoll_ctl (uint32_t vep_handle, int op, uint32_t session_handle,
          goto done;
        }
 
-      txf = vcl_session_is_ct (s) ? s->ct_tx_fifo : s->tx_fifo;
-      if (txf)
+      /* Generate EPOLLOUT if session write ready and event was not on */
+      if ((event->events & EPOLLOUT) && !(s->vep.ev.events & EPOLLOUT))
        {
-         if (event->events & EPOLLOUT)
-           svm_fifo_add_want_deq_ntf (txf, SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL);
+         /* Fifo size load acq synchronized with update store rel */
+         int write_ready = vcl_session_write_ready (s);
+
+         vcl_session_add_want_deq_ntf (s, SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL);
+         if (write_ready > 0)
+           vcl_epoll_ctl_add_unhandled_event (wrk, s, event->events & EPOLLET,
+                                              SESSION_IO_EVT_TX);
          else
-           svm_fifo_del_want_deq_ntf (txf, SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL);
+           /* Request deq ntf in case dequeue happened while updating flag */
+           vcl_session_add_want_deq_ntf (s, SVM_FIFO_WANT_DEQ_NOTIF);
        }
+      else if (!(event->events & EPOLLOUT))
+       vcl_session_del_want_deq_ntf (s, SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL);
 
-      /* Generate EPOLLOUT if session write ready nd event was not on */
-      if ((event->events & EPOLLOUT) && !(s->vep.ev.events & EPOLLOUT) &&
-         (vcl_session_write_ready (s) > 0))
-       {
-         vcl_epoll_ctl_add_unhandled_event (wrk, s, event->events & EPOLLET,
-                                            SESSION_IO_EVT_TX);
-       }
       /* Generate EPOLLIN if session read ready and event was not on */
       if ((event->events & EPOLLIN) && !(s->vep.ev.events & EPOLLIN) &&
          (vcl_session_read_ready (s) > 0))
@@ -3014,11 +3015,7 @@ vppcom_epoll_ctl (uint32_t vep_handle, int op, uint32_t session_handle,
       s->flags &= ~VCL_SESSION_F_IS_VEP_SESSION;
 
       if (vcl_session_is_open (s))
-       {
-         txf = vcl_session_is_ct (s) ? s->ct_tx_fifo : s->tx_fifo;
-         if (txf)
-           svm_fifo_del_want_deq_ntf (txf, SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL);
-       }
+       vcl_session_del_want_deq_ntf (s, SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL);
 
       VDBG (1, "EPOLL_CTL_DEL: vep_idx %u, sh %u!", vep_handle,
            session_handle);
@@ -3073,7 +3070,8 @@ vcl_epoll_wait_handle_mq_event (vcl_worker_t * wrk, session_event_t * e,
       svm_fifo_reset_has_deq_ntf (vcl_session_is_ct (s) ? s->ct_tx_fifo :
                                                                s->tx_fifo);
       session_events = s->vep.ev.events;
-      if (!(EPOLLOUT & session_events))
+      if (!(EPOLLOUT & session_events) ||
+         (s->vep.lt_next != VCL_INVALID_SESSION_INDEX))
        break;
       add_event = 1;
       events[*num_ev].events = EPOLLOUT;
@@ -3108,12 +3106,10 @@ vcl_epoll_wait_handle_mq_event (vcl_worker_t * wrk, session_event_t * e,
        break;
       session_events = s->vep.ev.events;
       /* Generate EPOLLOUT because there's no connected event */
-      if (!(EPOLLOUT & session_events) || !s->tx_fifo)
+      if (!(EPOLLOUT & session_events))
        break;
       /* We didn't have a fifo when the event was added */
-      svm_fifo_add_want_deq_ntf (
-       (vcl_session_is_ct (s) ? s->ct_tx_fifo : s->tx_fifo),
-       SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL);
+      vcl_session_add_want_deq_ntf (s, SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL);
       add_event = 1;
       events[*num_ev].events = EPOLLOUT;
       session_evt_data = s->vep.ev.data.u64;