X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=ofproto%2Fofproto.c;h=1a653ec4113bf46fd04675747c486ad40c6c5452;hb=ee402caec46c116a862b716cb4851ff5be371c9f;hp=189aa2c827a96ee04eb2b02db178e5fd23064799;hpb=02dd3123a0e312f1d33403e744af52dd6096f12d;p=openvswitch

diff --git a/ofproto/ofproto.c b/ofproto/ofproto.c
index 189aa2c8..1a653ec4 100644
--- a/ofproto/ofproto.c
+++ b/ofproto/ofproto.c
@@ -808,8 +808,8 @@ ofproto_run1(struct ofproto *p)
                 /* Someone destroyed the datapath behind our back.  The caller
                  * better destroy us and give up, because we're just going to
                  * spin from here on out. */
-                static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
-                VLOG_ERR_RL(&rl, "%s: datapath was destroyed externally",
+                static struct vlog_rate_limit rl2 = VLOG_RATE_LIMIT_INIT(1, 5);
+                VLOG_ERR_RL(&rl2, "%s: datapath was destroyed externally",
                             dpif_name(p->dpif));
                 return ENODEV;
             }
@@ -2559,6 +2559,9 @@ struct flow_stats_cbdata {
     struct ofpbuf *msg;
 };
 
+/* Obtains statistic counters for 'rule' within 'p' and stores them into
+ * '*packet_countp' and '*byte_countp'.  If 'rule' is a wildcarded rule, the
+ * returned statistic include statistics for all of 'rule''s subrules. */
 static void
 query_stats(struct ofproto *p, struct rule *rule,
             uint64_t *packet_countp, uint64_t *byte_countp)
@@ -2568,9 +2571,19 @@ query_stats(struct ofproto *p, struct rule *rule,
     struct odp_flow *odp_flows;
     size_t n_odp_flows;
 
+    /* Start from historical data for 'rule' itself that are no longer tracked
+     * by the datapath.  This counts, for example, subrules that have
+     * expired. */
     packet_count = rule->packet_count;
     byte_count = rule->byte_count;
 
+    /* Prepare to ask the datapath for statistics on 'rule', or if it is
+     * wildcarded then on all of its subrules.
+     *
+     * Also, add any statistics that are not tracked by the datapath for each
+     * subrule.  This includes, for example, statistics for packets that were
+     * executed "by hand" by ofproto via dpif_execute() but must be accounted
+     * to a flow. */
     n_odp_flows = rule->cr.wc.wildcards ? list_size(&rule->list) : 1;
     odp_flows = xzalloc(n_odp_flows * sizeof *odp_flows);
     if (rule->cr.wc.wildcards) {
@@ -2584,8 +2597,7 @@ query_stats(struct ofproto *p, struct rule *rule,
         odp_flows[0].key = rule->cr.flow;
     }
 
-    packet_count = rule->packet_count;
-    byte_count = rule->byte_count;
+    /* Fetch up-to-date statistics from the datapath and add them in. */
     if (!dpif_flow_get_multiple(p->dpif, odp_flows, n_odp_flows)) {
         size_t i;
         for (i = 0; i < n_odp_flows; i++) {
@@ -2596,6 +2608,7 @@ query_stats(struct ofproto *p, struct rule *rule,
     }
     free(odp_flows);
 
+    /* Return the stats to the caller. */
     *packet_countp = packet_count;
     *byte_countp = byte_count;
 }