[ovs-dev] [PATCH] ofproto-dpif: Don't put new subfacets as result of "userspace" action.

[Ethan Jackson]

This makes me a bit uncomfortable because we're going to have facet's floating
around which have never been installed.  I would expect the rest of ofproto-dpif
to be unhappy about that, though I can't say exactly how.  At any rate, how
about an alternative approach.  If a packet came in as DPIF_UC_ACTION, simply
never install it.  Something like what I have below.

Now that I look at it, in the below patch, we'll have to add the stats to facet
if we decide to bail out, but you get the gist of it.

Thoughts?
Ethan

---
 ofproto/ofproto-dpif.c |   14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/ofproto/ofproto-dpif.c b/ofproto/ofproto-dpif.c
index 67e6c7a..31d463f 100644
--- a/ofproto/ofproto-dpif.c
+++ b/ofproto/ofproto-dpif.c
@@ -3395,11 +3395,7 @@ handle_flow_miss_with_facet(struct flow_miss *miss, struct facet *facet,
     struct subfacet *subfacet;
     struct ofpbuf *packet;
 
-    subfacet = subfacet_create(facet, miss, now);
     want_path = facet->xout.slow ? SF_SLOW_PATH : SF_FAST_PATH;
-    if (stats) {
-        subfacet_update_stats(subfacet, stats);
-    }
 
     LIST_FOR_EACH (packet, list_node, &miss->packets) {
         struct flow_miss_op *op = &ops[*n_ops];
@@ -3426,6 +3422,16 @@ handle_flow_miss_with_facet(struct flow_miss *miss, struct facet *facet,
         }
     }
 
+    if (miss->upcall_type == DPIF_UC_ACTION
+        && !list_is_empty(&facet->subfacets)) {
+        return;
+    }
+
+    subfacet = subfacet_create(facet, miss, now);
+    if (stats) {
+        subfacet_update_stats(subfacet, stats);
+    }
+
     if (miss->upcall_type == DPIF_UC_MISS || subfacet->path != want_path) {
         struct flow_miss_op *op = &ops[(*n_ops)++];
         struct dpif_flow_put *put = &op->dpif_op.u.flow_put;
-- 
1.7.9.5