[orchagent] Add separate next hop table and orch

**What I did**
Added a new next hop group table to APP_DB, and orchagent support
to use this as an alternative to including next hop information in
the route table

**Why I did it**
Improves performance and occupancy usage when using the new table

**How I verified it**
Extended SWSS unit tests to cover new code, and ran existing tests

Signed-off-by: Thomas Cappleman <thomas.cappleman@metaswitch.com>

.gitignore

@@ -77,3 +77,7 @@ tests/mock_tests/tests.trs
 tests/test-suite.log
 tests/tests.log
 tests/tests.trs
+
+# IDE files #
+#############
+.vscode

doc/swss-schema.md

@@ -159,8 +159,29 @@ and reflects the LAG ports into the redis under: `LAG_TABLE:<team0>:port`
     ;Status: Mandatory
     key           = ROUTE_TABLE:prefix
     nexthop       = *prefix, ;IP addresses separated “,” (empty indicates no gateway)
-    intf          = ifindex? PORT_TABLE.key  ; zero or more separated by “,” (zero indicates no interface)
-    blackhole     = BIT ; Set to 1 if this route is a blackhole (or null0)
+    ifname        = ifindex? PORT_TABLE.key  ; zero or more separated by “,” (zero indicates no interface)
+    weight        = weight_list              ; List of weights.
+    nexthop_group = string ; index within the NEXT_HOP_GROUP_TABLE, used instead of nexthop and intf fields
+
+---------------------------------------------
+
+###### LABEL_ROUTE_TABLE
+; Defines schema for MPLS label route table attributes
+key           = LABEL_ROUTE_TABLE:mpls_label ; MPLS label
+; field       = value
+nexthop       = STRING                   ; Comma-separated list of nexthops.
+ifname        = STRING                   ; Comma-separated list of interfaces.
+weight        = STRING                   ; Comma-separated list of weights.
+nexthop_group = string ; index within the NEXT_HOP_GROUP_TABLE, used instead of nexthop and intf fields
+
+---------------------------------------------
+### NEXT_HOP_GROUP_TABLE
+    ;Stores a list of groups of one or more next hops
+    ;Status: Mandatory
+    key           = NEXT_HOP_GROUP_TABLE:string ; arbitrary index for the next hop group
+    nexthop       = *prefix, ;IP addresses separated “,” (empty indicates no gateway)
+    ifname        = ifindex? PORT_TABLE.key  ; zero or more separated by “,” (zero indicates no interface)
+    weight        = weight_list              ; List of weights.
 
 ---------------------------------------------
 ### NEIGH_TABLE

orchagent/Makefile.am

@@ -31,6 +31,7 @@ orchagent_SOURCES = \
             orchdaemon.cpp \
             orch.cpp \
             notifications.cpp \
+            nhgorch.cpp \ 
             routeorch.cpp \
             neighorch.cpp \
             intfsorch.cpp \

orchagent/neighorch.cpp

@@ -7,6 +7,7 @@
 #include "directory.h"
 #include "muxorch.h"
 #include "subscriberstatetable.h"
+#include "nhgorch.h"
 
 extern sai_neighbor_api_t*         sai_neighbor_api;
 extern sai_next_hop_api_t*         sai_next_hop_api;
@@ -15,6 +16,7 @@ extern PortsOrch *gPortsOrch;
 extern sai_object_id_t gSwitchId;
 extern CrmOrch *gCrmOrch;
 extern RouteOrch *gRouteOrch;
+extern NhgOrch *gNhgOrch;
 extern FgNhgOrch *gFgNhgOrch;
 extern Directory<Orch*> gDirectory;
 extern string gMySwitchType;
@@ -31,7 +33,7 @@ NeighOrch::NeighOrch(DBConnector *appDb, string tableName, IntfsOrch *intfsOrch,
     SWSS_LOG_ENTER();
 
     m_fdbOrch->attach(this);
-    
+
     if(gMySwitchType == "voq")
     {
         //Add subscriber to process VOQ system neigh
@@ -149,10 +151,12 @@ bool NeighOrch::hasNextHop(const NextHopKey &nexthop)
     return m_syncdNextHops.find(nexthop) != m_syncdNextHops.end();
 }
 
-bool NeighOrch::addNextHop(NextHopKey &nexthop)
+bool NeighOrch::addNextHop(const NextHopKey &const_nexthop)
 {
     SWSS_LOG_ENTER();
 
+    NextHopKey nexthop = {const_nexthop.ip_address, const_nexthop.alias};
+
     Port p;
     if (!gPortsOrch->getPort(nexthop.alias, p))
     {
@@ -283,6 +287,7 @@ bool NeighOrch::setNextHopFlag(const NextHopKey &nexthop, const uint32_t nh_flag
     {
         case NHFLAGS_IFDOWN:
             rc = gRouteOrch->invalidnexthopinNextHopGroup(nexthop, count);
+            rc &= gNhgOrch->invalidateNextHop(nexthop);
             break;
         default:
             assert(0);
@@ -312,6 +317,7 @@ bool NeighOrch::clearNextHopFlag(const NextHopKey &nexthop, const uint32_t nh_fl
     {
         case NHFLAGS_IFDOWN:
             rc = gRouteOrch->validnexthopinNextHopGroup(nexthop, count);
+            rc &= gNhgOrch->validateNextHop(nexthop);
             break;
         default:
             assert(0);
@@ -371,10 +377,12 @@ bool NeighOrch::ifChangeInformNextHop(const string &alias, bool if_up)
     return rc;
 }
 
-bool NeighOrch::removeNextHop(NextHopKey& nexthop)
+bool NeighOrch::removeNextHop(const NextHopKey& const_nexthop)
 {
     SWSS_LOG_ENTER();
 
+    NextHopKey nexthop = {const_nexthop.ip_address, const_nexthop.alias};
+
     if(m_intfsOrch->isRemoteSystemPortIntf(nexthop.alias))
     {
         //For remote system ports kernel nexthops are always on inband. Change the key
@@ -874,7 +882,7 @@ bool NeighOrch::removeNeighbor(const NeighborEntry &neighborEntry, bool disable)
 
     NeighborUpdate update = { neighborEntry, MacAddress(), false };
     notify(SUBJECT_TYPE_NEIGH_CHANGE, static_cast<void *>(&update));
-    
+
     if(gMySwitchType == "voq")
     {
         //Sync the neighbor to delete from the CHASSIS_APP_DB

orchagent/neighorch.h

@@ -48,8 +48,8 @@ class NeighOrch : public Orch, public Subject, public Observer
     ~NeighOrch();
 
     bool hasNextHop(const NextHopKey&);
-    bool addNextHop(NextHopKey&);
-    bool removeNextHop(NextHopKey&);
+    bool addNextHop(const NextHopKey&);
+    bool removeNextHop(const NextHopKey&);
 
     sai_object_id_t getNextHopId(const NextHopKey&);
     sai_object_id_t getLocalNextHopId(const NextHopKey&);

orchagent/nexthopkey.h

@@ -4,6 +4,7 @@
 #include "ipaddress.h"
 #include "tokenize.h"
 #include "label.h"
+#include "intfsorch.h"
 
 #define NH_DELIMITER '@'
 #define NHG_DELIMITER ','
@@ -23,6 +24,8 @@ struct NextHopKey
     NextHopKey(const IpAddress &ip, const std::string &alias) : ip_address(ip), alias(alias), vni(0), mac_address() {}
     NextHopKey(const std::string &str)
     {
+        SWSS_LOG_ENTER();
+
         if (str.find(NHG_DELIMITER) != string::npos)
         {
             std::string err = "Error converting " + str + " to NextHop";
@@ -32,16 +35,19 @@ struct NextHopKey
         std::string ip_str;
         if (label_delimiter != std::string::npos)
         {
+            SWSS_LOG_INFO("Labeled next hop");
             label_stack = LabelStack(str.substr(0, label_delimiter));
             ip_str = str.substr(label_delimiter+1);
         }
         else
         {
+            SWSS_LOG_INFO("Unlabeled next hop");
             ip_str = str;
         }
         auto keys = tokenize(ip_str, NH_DELIMITER);
         vni = 0;
         mac_address = MacAddress();
+
         if (keys.size() == 1)
         {
             ip_address = keys[0];
@@ -62,6 +68,7 @@ struct NextHopKey
             throw std::invalid_argument(err);
         }
     }
+
     NextHopKey(const std::string &str, bool overlay_nh)
     {
         if (str.find(NHG_DELIMITER) != string::npos)
@@ -136,6 +143,11 @@ struct NextHopKey
     {
         return (ip_address.getV4Addr() == 0);
     }
+
+    NextHopKey ipKey() const
+    {
+        return NextHopKey(ip_address, alias);
+    }
 };
 
 #endif /* SWSS_NEXTHOPKEY_H */