zclient: Register all nexthops contained in RIBs

Currently, zclient registers only nexthops which bound for the best
path, this patch enables to register all nexthops which contained in
RIBs in order to detect nexthops down faster.

Signed-off-by: IWASE Yusuke <iwase.yusuke0@gmail.com>

1 files changed, 47 insertions, 33 deletions

diff --git a/server/zclient.go b/server/zclient.go
index bb17613f..46cab1a1 100644
--- a/server/zclient.go
+++ b/server/zclient.go
@@ -180,10 +180,24 @@ func (m *nexthopTrackingManager) scheduleUpdate(paths pathList) {
 	m.pathListCh <- paths
 }
 
-func filterOutNilPath(paths pathList) pathList {
+func (m *nexthopTrackingManager) filterPathToRegister(paths pathList) pathList {
 	filteredPaths := make(pathList, 0, len(paths))
 	for _, path := range paths {
-		if path == nil {
+		if path == nil || path.IsFromExternal() {
+			continue
+		}
+		// NEXTHOP_UNREGISTER message will be sent when GoBGP received
+		// NEXTHOP_UPDATE message and there is no path bound for the updated
+		// nexthop.
+		// Here filters out withdraw paths and paths whose nexthop is:
+		// - already invalidated
+		// - already registered
+		// - unspecified address
+		if path.IsWithdraw || path.IsNexthopInvalid {
+			continue
+		}
+		nexthop := path.GetNexthop()
+		if m.isRegisteredNexthop(nexthop) || nexthop.IsUnspecified() {
 			continue
 		}
 		filteredPaths = append(filteredPaths, path)
@@ -264,7 +278,7 @@ func newNexthopRegisterBody(dst pathList, nhtManager *nexthopTrackingManager) (b
 		return nil, false
 	}
 
-	paths := filterOutNilPath(dst)
+	paths := nhtManager.filterPathToRegister(dst)
 	if len(paths) == 0 {
 		return nil, false
 	}
@@ -281,15 +295,6 @@ func newNexthopRegisterBody(dst pathList, nhtManager *nexthopTrackingManager) (b
 	nexthops := make([]*zebra.RegisteredNexthop, 0, len(paths))
 	for _, p := range paths {
 		nexthop := p.GetNexthop()
-		// Skips to register or unregister the given nexthop
-		// when the nexthop is:
-		// - already registered
-		// - already invalidated
-		// - an unspecified address
-		if nhtManager.isRegisteredNexthop(nexthop) || p.IsNexthopInvalid || nexthop.IsUnspecified() {
-			continue
-		}
-
 		var nh *zebra.RegisteredNexthop
 		switch family {
 		case bgp.RF_IPv4_UC, bgp.RF_IPv4_VPN:
@@ -303,7 +308,7 @@ func newNexthopRegisterBody(dst pathList, nhtManager *nexthopTrackingManager) (b
 				Prefix: nexthop.To16(),
 			}
 		default:
-			return nil, path.IsWithdraw
+			continue
 		}
 		nexthops = append(nexthops, nh)
 		nhtManager.registerNexthop(nexthop)
@@ -435,7 +440,10 @@ func (z *zebraClient) stop() {
 }
 
 func (z *zebraClient) loop() {
-	w := z.server.Watch(WatchBestPath(true))
+	w := z.server.Watch([]WatchOption{
+		WatchBestPath(true),
+		WatchPostUpdate(true),
+	}...)
 	defer w.Stop()
 
 	if z.nhtManager != nil {
@@ -468,30 +476,36 @@ func (z *zebraClient) loop() {
 				}
 			}
 		case ev := <-w.Event():
-			msg := ev.(*WatchEventBestPath)
-			if table.UseMultiplePaths.Enabled {
-				for _, dst := range msg.MultiPathList {
-					if body, isDelete := newIPRouteBody(dst); body != nil {
-						z.client.SendIPRoute(0, body, isDelete)
-					}
-					if body, isUnregister := newNexthopRegisterBody(dst, z.nhtManager); body != nil {
-						z.client.SendNexthopRegister(0, body, isUnregister)
-					}
-				}
-			} else {
-				for _, path := range msg.PathList {
-					if len(path.VrfIds) == 0 {
-						path.VrfIds = []uint16{0}
+			switch msg := ev.(type) {
+			case *WatchEventBestPath:
+				if table.UseMultiplePaths.Enabled {
+					for _, dst := range msg.MultiPathList {
+						if body, isWithdraw := newIPRouteBody(dst); body != nil {
+							z.client.SendIPRoute(0, body, isWithdraw)
+						}
+						if body, isWithdraw := newNexthopRegisterBody(dst, z.nhtManager); body != nil {
+							z.client.SendNexthopRegister(0, body, isWithdraw)
+						}
 					}
-					for _, i := range path.VrfIds {
-						if body, isWithdraw := newIPRouteBody(pathList{path}); body != nil {
-							z.client.SendIPRoute(i, body, isWithdraw)
+				} else {
+					for _, path := range msg.PathList {
+						if len(path.VrfIds) == 0 {
+							path.VrfIds = []uint16{0}
 						}
-						if body, isWithdraw := newNexthopRegisterBody(pathList{path}, z.nhtManager); body != nil {
-							z.client.SendNexthopRegister(i, body, isWithdraw)
+						for _, i := range path.VrfIds {
+							if body, isWithdraw := newIPRouteBody(pathList{path}); body != nil {
+								z.client.SendIPRoute(i, body, isWithdraw)
+							}
+							if body, isWithdraw := newNexthopRegisterBody(pathList{path}, z.nhtManager); body != nil {
+								z.client.SendNexthopRegister(i, body, isWithdraw)
+							}
 						}
 					}
 				}
+			case *WatchEventUpdate:
+				if body, isWithdraw := newNexthopRegisterBody(msg.PathList, z.nhtManager); body != nil {
+					z.client.SendNexthopRegister(0, body, isWithdraw)
+				}
 			}
 		}
 	}