Fix leak due to cid queue never getting cleaned up (#756)

* Fix leak due to cid queue never getting cleaned up

This removes entries from the queue portion of CidQueue that were removed from the map portion.

* Remove unused cidQueue function. Do not export cidQueue functions.

bitswap/client/internal/blockpresencemanager/blockpresencemanager.go

@@ -111,6 +111,10 @@ func (bpm *BlockPresenceManager) allDontHave(peers []peer.ID, c cid.Cid) bool {
 
 // RemoveKeys cleans up the given keys from the block presence map
 func (bpm *BlockPresenceManager) RemoveKeys(ks []cid.Cid) {
+	if len(ks) == 0 {
+		return
+	}
+
 	bpm.Lock()
 	defer bpm.Unlock()
 

bitswap/client/internal/session/cidqueue.go

@@ -14,7 +14,7 @@ func newCidQueue() *cidQueue {
 	return &cidQueue{eset: cid.NewSet()}
 }
 
-func (cq *cidQueue) Pop() cid.Cid {
+func (cq *cidQueue) pop() cid.Cid {
 	for {
 		if cq.elems.Len() == 0 {
 			return cid.Cid{}
@@ -29,43 +29,31 @@ func (cq *cidQueue) Pop() cid.Cid {
 	}
 }
 
-func (cq *cidQueue) Cids() []cid.Cid {
-	// Lazily delete from the list any cids that were removed from the set
-	if cq.elems.Len() > cq.eset.Len() {
-		for i := 0; i < cq.elems.Len(); i++ {
-			c := cq.elems.PopFront()
-			if cq.eset.Has(c) {
-				cq.elems.PushBack(c)
-			}
-		}
-	}
-
-	if cq.elems.Len() == 0 {
-		return nil
-	}
-
-	// Make a copy of the cids
-	cids := make([]cid.Cid, cq.elems.Len())
-	for i := 0; i < cq.elems.Len(); i++ {
-		cids[i] = cq.elems.At(i)
-	}
-	return cids
-}
-
-func (cq *cidQueue) Push(c cid.Cid) {
+func (cq *cidQueue) push(c cid.Cid) {
 	if cq.eset.Visit(c) {
 		cq.elems.PushBack(c)
 	}
 }
 
-func (cq *cidQueue) Remove(c cid.Cid) {
+func (cq *cidQueue) remove(c cid.Cid) {
 	cq.eset.Remove(c)
 }
 
-func (cq *cidQueue) Has(c cid.Cid) bool {
+func (cq *cidQueue) has(c cid.Cid) bool {
 	return cq.eset.Has(c)
 }
 
-func (cq *cidQueue) Len() int {
+func (cq *cidQueue) len() int {
 	return cq.eset.Len()
 }
+
+func (cq *cidQueue) gc() {
+	if cq.elems.Len() > cq.eset.Len() {
+		for i := 0; i < cq.elems.Len(); i++ {
+			c := cq.elems.PopFront()
+			if cq.eset.Has(c) {
+				cq.elems.PushBack(c)
+			}
+		}
+	}
+}

bitswap/client/internal/session/sessionwants.go

@@ -35,13 +35,13 @@ func newSessionWants(broadcastLimit int) sessionWants {
 }
 
 func (sw *sessionWants) String() string {
-	return fmt.Sprintf("%d pending / %d live", sw.toFetch.Len(), len(sw.liveWants))
+	return fmt.Sprintf("%d pending / %d live", sw.toFetch.len(), len(sw.liveWants))
 }
 
 // BlocksRequested is called when the client makes a request for blocks
 func (sw *sessionWants) BlocksRequested(newWants []cid.Cid) {
 	for _, k := range newWants {
-		sw.toFetch.Push(k)
+		sw.toFetch.push(k)
 	}
 }
 
@@ -56,14 +56,14 @@ func (sw *sessionWants) GetNextWants() []cid.Cid {
 	// limit)
 	currentLiveCount := len(sw.liveWants)
 	toAdd := sw.broadcastLimit - currentLiveCount
-	liveSize := min(toAdd, sw.toFetch.Len())
+	liveSize := min(toAdd, sw.toFetch.len())
 	if liveSize <= 0 {
 		return nil
 	}
 
 	live := make([]cid.Cid, 0, liveSize)
-	for ; toAdd > 0 && sw.toFetch.Len() > 0; toAdd-- {
-		c := sw.toFetch.Pop()
+	for ; toAdd > 0 && sw.toFetch.len() > 0; toAdd-- {
+		c := sw.toFetch.pop()
 		live = append(live, c)
 		sw.liveWantsOrder = append(sw.liveWantsOrder, c)
 		sw.liveWants[c] = now
@@ -76,12 +76,13 @@ func (sw *sessionWants) GetNextWants() []cid.Cid {
 func (sw *sessionWants) WantsSent(ks []cid.Cid) {
 	now := time.Now()
 	for _, c := range ks {
-		if _, ok := sw.liveWants[c]; !ok && sw.toFetch.Has(c) {
-			sw.toFetch.Remove(c)
+		if _, ok := sw.liveWants[c]; !ok && sw.toFetch.has(c) {
+			sw.toFetch.remove(c)
 			sw.liveWantsOrder = append(sw.liveWantsOrder, c)
 			sw.liveWants[c] = now
 		}
 	}
+	sw.toFetch.gc()
 }
 
 // BlocksReceived removes received block CIDs from the live wants list and
@@ -108,9 +109,10 @@ func (sw *sessionWants) BlocksReceived(ks []cid.Cid) ([]cid.Cid, time.Duration)
 
 			// Remove the CID from the live wants / toFetch queue
 			delete(sw.liveWants, c)
-			sw.toFetch.Remove(c)
+			sw.toFetch.remove(c)
 		}
 	}
+	sw.toFetch.gc()
 
 	// If the live wants ordering array is a long way out of sync with the
 	// live wants map, clean up the ordering array
@@ -152,9 +154,10 @@ func (sw *sessionWants) PrepareBroadcast() []cid.Cid {
 // CancelPending removes the given CIDs from the fetch queue.
 func (sw *sessionWants) CancelPending(keys []cid.Cid) {
 	for _, k := range keys {
-		sw.toFetch.Remove(k)
+		sw.toFetch.remove(k)
 		delete(sw.liveWants, k)
 	}
+	sw.toFetch.gc()
 }
 
 // LiveWants returns a list of live wants
@@ -193,7 +196,7 @@ func (sw *sessionWants) HasLiveWants() bool {
 func (sw *sessionWants) isWanted(c cid.Cid) bool {
 	_, ok := sw.liveWants[c]
 	if !ok {
-		ok = sw.toFetch.Has(c)
+		ok = sw.toFetch.has(c)
 	}
 	return ok
 }