From f8db49e7e488ba2d1daf7195edae18bbcec7c5d3 Mon Sep 17 00:00:00 2001
From: Conner Fromknecht <conner@lightning.engineering>
Date: Thu, 6 Jun 2019 13:02:16 +0200
Subject: [PATCH] routing/router: remove router-level reject cache

This is now redundant since we have one at the db-level
---
 routing/router.go | 40 ----------------------------------------
 1 file changed, 40 deletions(-)

diff --git a/routing/router.go b/routing/router.go
index fd0f689a..cbd52c0a 100644
--- a/routing/router.go
+++ b/routing/router.go
@@ -380,9 +380,6 @@ type ChannelRouter struct {
 	// consistency between the various database accesses.
 	channelEdgeMtx *multimutex.Mutex
 
-	rejectMtx   sync.RWMutex
-	rejectCache map[uint64]struct{}
-
 	sync.RWMutex
 
 	quit chan struct{}
@@ -412,7 +409,6 @@ func New(cfg Config) (*ChannelRouter, error) {
 		ntfnClientUpdates: make(chan *topologyClientUpdate),
 		channelEdgeMtx:    multimutex.NewMutex(),
 		selfNode:          selfNode,
-		rejectCache:       make(map[uint64]struct{}),
 		quit:              make(chan struct{}),
 	}
 
@@ -803,17 +799,9 @@ func (r *ChannelRouter) pruneZombieChans() error {
 		// TODO(roasbeef): add ability to delete single directional edge
 		chansToPrune = append(chansToPrune, info.ChannelID)
 
-		// As we're detecting this as a zombie channel, we'll add this
-		// to the set of recently rejected items so we don't re-accept
-		// it shortly after.
-		r.rejectCache[info.ChannelID] = struct{}{}
-
 		return nil
 	}
 
-	r.rejectMtx.Lock()
-	defer r.rejectMtx.Unlock()
-
 	err := r.cfg.Graph.ForEachChannel(filterPruneChans)
 	if err != nil {
 		return fmt.Errorf("unable to filter local zombie channels: "+
@@ -1119,16 +1107,6 @@ func (r *ChannelRouter) processUpdate(msg interface{}) error {
 		log.Infof("Updated vertex data for node=%x", msg.PubKeyBytes)
 
 	case *channeldb.ChannelEdgeInfo:
-		// If we recently rejected this channel edge, then we won't
-		// attempt to re-process it.
-		r.rejectMtx.RLock()
-		if _, ok := r.rejectCache[msg.ChannelID]; ok {
-			r.rejectMtx.RUnlock()
-			return newErrf(ErrRejected, "recently rejected "+
-				"chan_id=%v", msg.ChannelID)
-		}
-		r.rejectMtx.RUnlock()
-
 		// Prior to processing the announcement we first check if we
 		// already know of this channel, if so, then we can exit early.
 		_, _, exists, isZombie, err := r.cfg.Graph.HasChannelEdge(
@@ -1168,10 +1146,6 @@ func (r *ChannelRouter) processUpdate(msg interface{}) error {
 		channelID := lnwire.NewShortChanIDFromInt(msg.ChannelID)
 		fundingPoint, _, err := r.fetchChanPoint(&channelID)
 		if err != nil {
-			r.rejectMtx.Lock()
-			r.rejectCache[msg.ChannelID] = struct{}{}
-			r.rejectMtx.Unlock()
-
 			return errors.Errorf("unable to fetch chan point for "+
 				"chan_id=%v: %v", msg.ChannelID, err)
 		}
@@ -1198,10 +1172,6 @@ func (r *ChannelRouter) processUpdate(msg interface{}) error {
 			r.quit,
 		)
 		if err != nil {
-			r.rejectMtx.Lock()
-			r.rejectCache[msg.ChannelID] = struct{}{}
-			r.rejectMtx.Unlock()
-
 			return fmt.Errorf("unable to fetch utxo "+
 				"for chan_id=%v, chan_point=%v: %v",
 				msg.ChannelID, fundingPoint, err)
@@ -1250,16 +1220,6 @@ func (r *ChannelRouter) processUpdate(msg interface{}) error {
 		}
 
 	case *channeldb.ChannelEdgePolicy:
-		// If we recently rejected this channel edge, then we won't
-		// attempt to re-process it.
-		r.rejectMtx.RLock()
-		if _, ok := r.rejectCache[msg.ChannelID]; ok {
-			r.rejectMtx.RUnlock()
-			return newErrf(ErrRejected, "recently rejected "+
-				"chan_id=%v", msg.ChannelID)
-		}
-		r.rejectMtx.RUnlock()
-
 		// We make sure to hold the mutex for this channel ID,
 		// such that no other goroutine is concurrently doing
 		// database accesses for the same channel ID.