vlib: multiarch vlib_frame_queue_dequeue()

Fact that it needs to copy buffer indices justifies this move.

Type: improvement
Change-Id: I5eb815ccc4cca0ef70b092eb83a49b713efdcbeb
Signed-off-by: Damjan Marion <damarion@cisco.com>

1 files changed, 123 insertions, 0 deletions

diff --git a/src/vlib/buffer_funcs.c b/src/vlib/buffer_funcs.c
index a0edd7ec60b..fcef2d80f35 100644
--- a/src/vlib/buffer_funcs.c
+++ b/src/vlib/buffer_funcs.c
@@ -361,6 +361,127 @@ CLIB_MULTIARCH_FN (vlib_buffer_enqueue_to_thread_fn)
 
 CLIB_MARCH_FN_REGISTRATION (vlib_buffer_enqueue_to_thread_fn);
 
+/*
+ * Check the frame queue to see if any frames are available.
+ * If so, pull the packets off the frames and put them to
+ * the handoff node.
+ */
+u32 __clib_section (".vlib_frame_queue_dequeue_fn")
+CLIB_MULTIARCH_FN (vlib_frame_queue_dequeue_fn)
+(vlib_main_t *vm, vlib_frame_queue_main_t *fqm)
+{
+  u32 thread_id = vm->thread_index;
+  vlib_frame_queue_t *fq = fqm->vlib_frame_queues[thread_id];
+  vlib_frame_queue_elt_t *elt;
+  u32 *from, *to;
+  vlib_frame_t *f;
+  int msg_type;
+  int processed = 0;
+  u32 vectors = 0;
+
+  ASSERT (fq);
+  ASSERT (vm == vlib_global_main.vlib_mains[thread_id]);
+
+  if (PREDICT_FALSE (fqm->node_index == ~0))
+    return 0;
+  /*
+   * Gather trace data for frame queues
+   */
+  if (PREDICT_FALSE (fq->trace))
+    {
+      frame_queue_trace_t *fqt;
+      frame_queue_nelt_counter_t *fqh;
+      u32 elix;
+
+      fqt = &fqm->frame_queue_traces[thread_id];
+
+      fqt->nelts = fq->nelts;
+      fqt->head = fq->head;
+      fqt->head_hint = fq->head_hint;
+      fqt->tail = fq->tail;
+      fqt->threshold = fq->vector_threshold;
+      fqt->n_in_use = fqt->tail - fqt->head;
+      if (fqt->n_in_use >= fqt->nelts)
+	{
+	  // if beyond max then use max
+	  fqt->n_in_use = fqt->nelts - 1;
+	}
+
+      /* Record the number of elements in use in the histogram */
+      fqh = &fqm->frame_queue_histogram[thread_id];
+      fqh->count[fqt->n_in_use]++;
+
+      /* Record a snapshot of the elements in use */
+      for (elix = 0; elix < fqt->nelts; elix++)
+	{
+	  elt = fq->elts + ((fq->head + 1 + elix) & (fq->nelts - 1));
+	  if (1 || elt->valid)
+	    {
+	      fqt->n_vectors[elix] = elt->n_vectors;
+	    }
+	}
+      fqt->written = 1;
+    }
+
+  while (1)
+    {
+      vlib_buffer_t *b;
+      if (fq->head == fq->tail)
+	{
+	  fq->head_hint = fq->head;
+	  return processed;
+	}
+
+      elt = fq->elts + ((fq->head + 1) & (fq->nelts - 1));
+
+      if (!elt->valid)
+	{
+	  fq->head_hint = fq->head;
+	  return processed;
+	}
+
+      from = elt->buffer_index;
+      msg_type = elt->msg_type;
+
+      ASSERT (msg_type == VLIB_FRAME_QUEUE_ELT_DISPATCH_FRAME);
+      ASSERT (elt->n_vectors <= VLIB_FRAME_SIZE);
+
+      f = vlib_get_frame_to_node (vm, fqm->node_index);
+
+      /* If the first vector is traced, set the frame trace flag */
+      b = vlib_get_buffer (vm, from[0]);
+      if (b->flags & VLIB_BUFFER_IS_TRACED)
+	f->frame_flags |= VLIB_NODE_FLAG_TRACE;
+
+      to = vlib_frame_vector_args (f);
+
+      vlib_buffer_copy_indices (to, from, elt->n_vectors);
+
+      vectors += elt->n_vectors;
+      f->n_vectors = elt->n_vectors;
+      vlib_put_frame_to_node (vm, fqm->node_index, f);
+
+      elt->valid = 0;
+      elt->n_vectors = 0;
+      elt->msg_type = 0xfefefefe;
+      CLIB_MEMORY_BARRIER ();
+      fq->head++;
+      processed++;
+
+      /*
+       * Limit the number of packets pushed into the graph
+       */
+      if (vectors >= fq->vector_threshold)
+	{
+	  fq->head_hint = fq->head;
+	  return processed;
+	}
+    }
+  ASSERT (0);
+  return processed;
+}
+CLIB_MARCH_FN_REGISTRATION (vlib_frame_queue_dequeue_fn);
+
 #ifndef CLIB_MARCH_VARIANT
 vlib_buffer_func_main_t vlib_buffer_func_main;
 
@@ -374,6 +495,8 @@ vlib_buffer_funcs_init (vlib_main_t *vm)
     CLIB_MARCH_FN_POINTER (vlib_buffer_enqueue_to_single_next_fn);
   bfm->buffer_enqueue_to_thread_fn =
     CLIB_MARCH_FN_POINTER (vlib_buffer_enqueue_to_thread_fn);
+  bfm->frame_queue_dequeue_fn =
+    CLIB_MARCH_FN_POINTER (vlib_frame_queue_dequeue_fn);
   return 0;
 }