ofproto-dpif: Store relevant fields for wildcarding in facet.

Dynamically determines the flow fields that were relevant in
processing flows based on the OpenFlow flow table and switch
configuration.  The immediate use for this functionality is to
cache action translations for similar flows in facets.  This yields
a roughly 80% improvement in flow set up rates for a complicated
flow table.

More importantly, these wildcards will be used to determine what to
wildcard for the forthcoming kernel wildcard (megaflow) patches
that will allow wildcarding in the kernel, which will provide
significant flow set up improvements.

The approach to tracking fields and caching action translations in
facets was based on an impressive prototype by Ethan Jackson.

Co-authored-by: Ethan Jackson <ethan@nicira.com>
Signed-off-by: Ethan Jackson <ethan@nicira.com>
Signed-off-by: Justin Pettit <jpettit@nicira.com>

1 files changed, 16 insertions, 4 deletions

diff --git a/lib/bond.c b/lib/bond.c
index aca18a2d..68ac0688 100644
--- a/lib/bond.c
+++ b/lib/bond.c
@@ -128,6 +128,7 @@ static struct bond_entry *lookup_bond_entry(const struct bond *,
 static tag_type bond_get_active_slave_tag(const struct bond *);
 static struct bond_slave *choose_output_slave(const struct bond *,
                                               const struct flow *,
+                                              struct flow_wildcards *,
                                               uint16_t vlan, tag_type *tags);
 static void bond_update_fake_slave_stats(struct bond *);
 
@@ -505,7 +506,7 @@ bond_compose_learning_packet(struct bond *bond,
 
     memset(&flow, 0, sizeof flow);
     memcpy(flow.dl_src, eth_src, ETH_ADDR_LEN);
-    slave = choose_output_slave(bond, &flow, vlan, &tags);
+    slave = choose_output_slave(bond, &flow, NULL, vlan, &tags);
 
     packet = ofpbuf_new(0);
     compose_rarp(packet, eth_src);
@@ -605,12 +606,17 @@ bond_check_admissibility(struct bond *bond, const void *slave_,
  * packet belongs to (so for an access port it will be the access port's VLAN).
  *
  * Adds a tag to '*tags' that associates the flow with the returned slave.
+ *
+ * If 'wc' is non-NULL, bitwise-OR's 'wc' with the set of bits that were
+ * significant in the selection.  At some point earlier, 'wc' should
+ * have been initialized (e.g., by flow_wildcards_init_catchall()).
  */
 void *
 bond_choose_output_slave(struct bond *bond, const struct flow *flow,
-                         uint16_t vlan, tag_type *tags)
+                         struct flow_wildcards *wc, uint16_t vlan,
+                         tag_type *tags)
 {
-    struct bond_slave *slave = choose_output_slave(bond, flow, vlan, tags);
+    struct bond_slave *slave = choose_output_slave(bond, flow, wc, vlan, tags);
     if (slave) {
         *tags |= slave->tag;
         return slave->aux;
@@ -1349,7 +1355,7 @@ lookup_bond_entry(const struct bond *bond, const struct flow *flow,
 
 static struct bond_slave *
 choose_output_slave(const struct bond *bond, const struct flow *flow,
-                    uint16_t vlan, tag_type *tags)
+                    struct flow_wildcards *wc, uint16_t vlan, tag_type *tags)
 {
     struct bond_entry *e;
 
@@ -1368,8 +1374,14 @@ choose_output_slave(const struct bond *bond, const struct flow *flow,
             /* Must have LACP negotiations for TCP balanced bonds. */
             return NULL;
         }
+        if (wc) {
+            flow_mask_hash_fields(wc, NX_HASH_FIELDS_SYMMETRIC_L4);
+        }
         /* Fall Through. */
     case BM_SLB:
+        if (wc) {
+            flow_mask_hash_fields(wc, NX_HASH_FIELDS_ETH_SRC);
+        }
         e = lookup_bond_entry(bond, flow, vlan);
         if (!e->slave || !e->slave->enabled) {
             e->slave = CONTAINER_OF(hmap_random_node(&bond->slaves),