Merge "Vrouter to generate EEXIST error appropriately" into R2.20

Juniper · Mar 7, 2016 · 367d5c6 · 367d5c6
2 parents 6ff5582 + 1e56a59
commit 367d5c6
Showing 1 changed file with 13 additions and 2 deletions.
diff --git a/dp-core/vr_flow.c b/dp-core/vr_flow.c
@@ -1691,7 +1691,7 @@ static int
 vr_flow_set(struct vrouter *router, vr_flow_req *req)
 {
     int ret;
-    unsigned int fe_index;
+    unsigned int fe_index = (unsigned int)-1;
     bool new_flow = false, modified = false;
 
     struct vr_flow_entry *fe = NULL, *rfe = NULL;
@@ -1735,8 +1735,19 @@ vr_flow_set(struct vrouter *router, vr_flow_req *req)
      */
     if (!fe) {
         fe = vr_add_flow_req(req, &fe_index);
-        if (!fe)
+        if (!fe) {
+            if (fe_index != (unsigned int)-1) {
+                /*
+                 * add flow req failed to allocate an entry due to race
+                 * between agent and datapath, where flow entry at fe_index
+                 * was already created due to packet trap, return EEXIST
+                 * error and allow agent to wait and handle flow add due to
+                 * packet trap
+                 */
+                return -EEXIST;
+            }
             return -ENOSPC;
+        }
 
         new_flow = true;
         infop->vfti_added++;