table: remove Destination's oldKnownPathList

Withdrawn pathes are kept to be referenced thus the memory for them
are not freed. Kill oldKnownPathList and Destination's NewFeed().

Destination's Calculate() returns the best paths.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

1 files changed, 32 insertions, 30 deletions

diff --git a/table/destination.go b/table/destination.go
index 31072561..8f9676b1 100644
--- a/table/destination.go
+++ b/table/destination.go
@@ -111,13 +111,12 @@ func NewPeerInfo(g *config.Global, p *config.Neighbor) *PeerInfo {
 }
 
 type Destination struct {
-	routeFamily      bgp.RouteFamily
-	nlri             bgp.AddrPrefixInterface
-	oldKnownPathList paths
-	knownPathList    paths
-	withdrawList     paths
-	newPathList      paths
-	RadixKey         string
+	routeFamily   bgp.RouteFamily
+	nlri          bgp.AddrPrefixInterface
+	knownPathList paths
+	withdrawList  paths
+	newPathList   paths
+	RadixKey      string
 }
 
 func NewDestination(nlri bgp.AddrPrefixInterface) *Destination {
@@ -201,15 +200,6 @@ func (dd *Destination) GetBestPath(id string) *Path {
 	return nil
 }
 
-func (dd *Destination) oldBest(id string) *Path {
-	for _, p := range dd.oldKnownPathList {
-		if p.Filtered(id) == POLICY_DIRECTION_NONE {
-			return p
-		}
-	}
-	return nil
-}
-
 func (dd *Destination) addWithdraw(withdraw *Path) {
 	dd.validatePath(withdraw)
 	dd.withdrawList = append(dd.withdrawList, withdraw)
@@ -236,8 +226,9 @@ func (dd *Destination) validatePath(path *Path) {
 //
 // Modifies destination's state related to stored paths. Removes withdrawn
 // paths from known paths. Also, adds new paths to known paths.
-func (dest *Destination) Calculate() ([]*Path, []*Path) {
-	dest.oldKnownPathList = dest.knownPathList
+func (dest *Destination) Calculate(ids []string) (map[string]*Path, []*Path, []*Path) {
+	best := make(map[string]*Path, len(ids))
+	oldKnownPathList := dest.knownPathList
 	updated := dest.newPathList
 	// First remove the withdrawn paths.
 	withdrawnList := dest.explicitWithdraw()
@@ -249,22 +240,33 @@ func (dest *Destination) Calculate() ([]*Path, []*Path) {
 	dest.newPathList = make([]*Path, 0)
 	// Compute new best path
 	dest.computeKnownBestPath()
-	return updated, withdrawnList
-}
 
-func (dest *Destination) NewFeed(id string) *Path {
-	old := dest.oldBest(id)
-	best := dest.GetBestPath(id)
-	if best != nil && best.Equal(old) {
-		return nil
-	}
-	if best == nil {
-		if old == nil {
+	f := func(id string) *Path {
+		old := func() *Path {
+			for _, p := range oldKnownPathList {
+				if p.Filtered(id) == POLICY_DIRECTION_NONE {
+					return p
+				}
+			}
+			return nil
+		}()
+		best := dest.GetBestPath(id)
+		if best != nil && best.Equal(old) {
 			return nil
 		}
-		return old.Clone(true)
+		if best == nil {
+			if old == nil {
+				return nil
+			}
+			return old.Clone(true)
+		}
+		return best
+	}
+
+	for _, id := range ids {
+		best[id] = f(id)
 	}
-	return best
+	return best, updated, withdrawnList
 }
 
 // Removes withdrawn paths.