qos: add support for port minimum bandwidth guarantee

Reported-At: https://bugzilla.redhat.com/show_bug.cgi?id=2060310
Signed-off-by: Ihar Hrachyshka <ihrachys@redhat.com>
Acked-by: Ales Musil <amusil@redhat.com>
Signed-off-by: Mark Michelson <mmichels@redhat.com>
(cherry picked from commit dbf12e5)
Signed-off-by: Numan Siddique <numans@ovn.org>

NEWS

@@ -1,5 +1,7 @@
 OVN v22.03.2 - xx xxx xxxx
 --------------------------
+  - Support (LSP.options:qos_min_rate) to guarantee minimal bandwidth available
+    for a logical port.
 
 OVN v22.03.1 - 03 Jun 2022
 --------------------------

controller/binding.c

@@ -51,6 +51,7 @@ VLOG_DEFINE_THIS_MODULE(binding);
 struct qos_queue {
     struct hmap_node node;
     uint32_t queue_id;
+    uint32_t min_rate;
     uint32_t max_rate;
     uint32_t burst;
 };
@@ -88,17 +89,19 @@ static void update_lport_tracking(const struct sbrec_port_binding *pb,
 static void
 get_qos_params(const struct sbrec_port_binding *pb, struct hmap *queue_map)
 {
+    uint32_t min_rate = smap_get_int(&pb->options, "qos_min_rate", 0);
     uint32_t max_rate = smap_get_int(&pb->options, "qos_max_rate", 0);
     uint32_t burst = smap_get_int(&pb->options, "qos_burst", 0);
     uint32_t queue_id = smap_get_int(&pb->options, "qdisc_queue_id", 0);
 
-    if ((!max_rate && !burst) || !queue_id) {
+    if ((!min_rate && !max_rate && !burst) || !queue_id) {
         /* Qos is not configured for this port. */
         return;
     }
 
     struct qos_queue *node = xzalloc(sizeof *node);
     hmap_insert(queue_map, &node->node, hash_int(queue_id, 0));
+    node->min_rate = min_rate;
     node->max_rate = max_rate;
     node->burst = burst;
     node->queue_id = queue_id;
@@ -238,9 +241,12 @@ setup_qos(const char *egress_iface, struct hmap *queue_map)
         HMAP_FOR_EACH_WITH_HASH (sb_info, node, hash_int(queue_id, 0),
                                  queue_map) {
             is_queue_needed = true;
-            if (sb_info->max_rate ==
+            if (sb_info->min_rate ==
+                smap_get_int(&queue_details, "min-rate", 0)
+                && sb_info->max_rate ==
                 smap_get_int(&queue_details, "max-rate", 0)
-                && sb_info->burst == smap_get_int(&queue_details, "burst", 0)) {
+                && sb_info->burst ==
+                smap_get_int(&queue_details, "burst", 0)) {
                 /* This queue is consistent. */
                 hmap_insert(&consistent_queues, &sb_info->node,
                             hash_int(queue_id, 0));
@@ -265,6 +271,7 @@ setup_qos(const char *egress_iface, struct hmap *queue_map)
         }
 
         smap_clear(&queue_details);
+        smap_add_format(&queue_details, "min-rate", "%d", sb_info->min_rate);
         smap_add_format(&queue_details, "max-rate", "%d", sb_info->max_rate);
         smap_add_format(&queue_details, "burst", "%d", sb_info->burst);
         error = netdev_set_queue(netdev_phy, sb_info->queue_id,

ovn-nb.xml

@@ -1029,6 +1029,11 @@
           <ref table="Interface" db="Open_vSwitch"/> table.
         </column>
 
+        <column name="options" key="qos_min_rate">
+          If set, indicates the minimum guaranteed rate available for data sent
+          from this interface, in bit/s.
+        </column>
+
         <column name="options" key="qos_max_rate">
           If set, indicates the maximum rate for data sent from this interface,
           in bit/s. The traffic will be shaped according to this limit.

ovn-sb.xml

@@ -3270,6 +3270,11 @@ tcp.flags = RST;
         <ref table="Interface" db="Open_vSwitch"/> table.
       </column>
 
+      <column name="options" key="qos_min_rate">
+        If set, indicates the minimum guaranteed rate available for data sent
+        from this interface, in bit/s.
+      </column>
+
       <column name="options" key="qos_max_rate">
         If set, indicates the maximum rate for data sent from this interface,
         in bit/s. The traffic will be shaped according to this limit.

tests/system-ovn.at

@@ -6345,13 +6345,15 @@ ovn-nbctl lsp-add sw0 public \
         -- lsp-set-type public localnet \
         -- lsp-set-options public network_name=phynet
 
+AT_CHECK([ovn-nbctl set Logical_Switch_Port public options:qos_min_rate=200000])
 AT_CHECK([ovn-nbctl set Logical_Switch_Port public options:qos_max_rate=300000])
 AT_CHECK([ovn-nbctl set Logical_Switch_Port public options:qos_burst=3000000])
 AT_CHECK([ovs-vsctl set interface ovs-public external-ids:ovn-egress-iface=true])
 OVS_WAIT_UNTIL([tc qdisc show | grep -q 'htb 1: dev ovs-public'])
 OVS_WAIT_UNTIL([tc class show dev ovs-public | \
-                grep -q 'class htb .* ceil 300Kbit burst 375000b cburst 375000b'])
+                grep -q 'class htb .* rate 200Kbit ceil 300Kbit burst 375000b cburst 375000b'])
 
+AT_CHECK([ovn-nbctl remove Logical_Switch_Port public options qos_min_rate=200000])
 AT_CHECK([ovn-nbctl remove Logical_Switch_Port public options qos_max_rate=300000])
 AT_CHECK([ovn-nbctl remove Logical_Switch_Port public options qos_burst=3000000])
 OVS_WAIT_UNTIL([test "$(tc qdisc show | grep 'htb 1: dev ovs-public')" = ""])