ofproto-dpif: Configure datapath max-idle through ovs-vsctl.

This patch adds a new configuration option, "max-idle" to the
Bridge "other-config" column. This sets how long datapath flows,
for the configured bridge, are cached in the datapath before
ovs-vswitchd thread expires them.

This commit is a backport of commit 72310b0 (upcall: Configure
datapath max-idle through ovs-vsctl.).

Signed-off-by: Alex Wang <[email protected]>
Acked-by: Joe Stringer <[email protected]>

ofproto/ofproto-dpif.c

@@ -4387,6 +4387,12 @@ subfacet_max_idle(const struct ofproto_dpif *ofproto)
     long long int now;
     int i;
 
+    /* If 'max_idle' is specified, uses it instead of doing the
+     * calculation. */
+    if (ofproto->up.max_idle) {
+        return ofproto->up.max_idle;
+    }
+
     total = hmap_count(&ofproto->subfacets);
     if (total <= ofproto->up.flow_eviction_threshold) {
         return N_BUCKETS * BUCKET_WIDTH;

ofproto/ofproto-provider.h

@@ -50,6 +50,7 @@ struct ofproto {
     unsigned flow_eviction_threshold; /* Threshold at which to begin flow
                                        * table eviction. Only affects the
                                        * ofproto-dpif implementation */
+    unsigned max_idle;
     bool forward_bpdu;          /* Option to allow forwarding of BPDU frames
                                  * when NORMAL action is invoked. */
     char *mfr_desc;             /* Manufacturer (NULL for default)b. */

ofproto/ofproto.c

@@ -570,6 +570,14 @@ ofproto_set_flow_eviction_threshold(struct ofproto *ofproto, unsigned threshold)
     }
 }
 
+/* Sets the maximum idle time for flows of 'ofproto' in the datapath before
+ * they are expired. */
+void
+ofproto_set_max_idle(struct ofproto *ofproto, unsigned max_idle)
+{
+    ofproto->max_idle = max_idle;
+}
+
 /* If forward_bpdu is true, the NORMAL action will forward frames with
  * reserved (e.g. STP) destination Ethernet addresses. if forward_bpdu is false,
  * the NORMAL action will drop these frames. */

ofproto/ofproto.h

@@ -222,6 +222,7 @@ void ofproto_set_extra_in_band_remotes(struct ofproto *,
                                        const struct sockaddr_in *, size_t n);
 void ofproto_set_in_band_queue(struct ofproto *, int queue_id);
 void ofproto_set_flow_eviction_threshold(struct ofproto *, unsigned threshold);
+void ofproto_set_max_idle(struct ofproto *, unsigned max_idle);
 void ofproto_set_forward_bpdu(struct ofproto *, bool forward_bpdu);
 void ofproto_set_mac_table_config(struct ofproto *, unsigned idle_time,
                                   size_t max_entries);

vswitchd/bridge.c

@@ -199,6 +199,7 @@ static void bridge_configure_flow_eviction_threshold(struct bridge *);
 static void bridge_configure_netflow(struct bridge *);
 static void bridge_configure_forward_bpdu(struct bridge *);
 static void bridge_configure_mac_table(struct bridge *);
+static void bridge_configure_max_idle(struct bridge *);
 static void bridge_configure_sflow(struct bridge *, int *sflow_bridge_number);
 static void bridge_configure_stp(struct bridge *);
 static void bridge_configure_tables(struct bridge *);
@@ -610,6 +611,7 @@ bridge_reconfigure_continue(const struct ovsrec_open_vswitch *ovs_cfg)
         bridge_configure_flow_eviction_threshold(br);
         bridge_configure_forward_bpdu(br);
         bridge_configure_mac_table(br);
+        bridge_configure_max_idle(br);
         bridge_configure_remotes(br, managers, n_managers);
         bridge_configure_netflow(br);
         bridge_configure_sflow(br, &sflow_bridge_number);
@@ -1493,6 +1495,22 @@ bridge_configure_flow_eviction_threshold(struct bridge *br)
     ofproto_set_flow_eviction_threshold(br->ofproto, threshold);
 }
 
+static void
+bridge_configure_max_idle(struct bridge *br)
+{
+    const char *max_idle_str;
+    unsigned max_idle;
+
+    max_idle_str = smap_get(&br->cfg->other_config,
+                            "max-idle");
+    if (max_idle_str) {
+        max_idle = strtoul(max_idle_str, NULL, 10);
+    } else {
+        max_idle = 0;
+    }
+    ofproto_set_max_idle(br->ofproto, max_idle);
+}
+
 /* Set forward BPDU option. */
 static void
 bridge_configure_forward_bpdu(struct bridge *br)