Some optimizations in PieceRequestOrder.Update and item comparisons

request-strategy/order.go

@@ -21,24 +21,19 @@ type (
 	ChunkSpec = types.ChunkSpec
 )
 
-type pieceOrderInput struct {
-	PieceRequestOrderState
-	PieceRequestOrderKey
-}
-
-func pieceOrderLess(i, j pieceOrderInput) multiless.Computation {
+func pieceOrderLess(i, j *pieceRequestOrderItem) multiless.Computation {
 	return multiless.New().Int(
-		int(j.Priority), int(i.Priority),
+		int(j.state.Priority), int(i.state.Priority),
 	).Bool(
-		j.Partial, i.Partial,
+		j.state.Partial, i.state.Partial,
 	).Int64(
-		i.Availability, j.Availability,
+		i.state.Availability, j.state.Availability,
 	).Int(
-		i.Index, j.Index,
+		i.key.Index, j.key.Index,
 	).Lazy(func() multiless.Computation {
 		return multiless.New().Cmp(bytes.Compare(
-			i.InfoHash[:],
-			j.InfoHash[:],
+			i.key.InfoHash[:],
+			j.key.InfoHash[:],
 		))
 	})
 }

request-strategy/piece-request-order.go

@@ -37,16 +37,7 @@ type pieceRequestOrderItem struct {
 
 func (me *pieceRequestOrderItem) Less(other btree.Item) bool {
 	otherConcrete := other.(*pieceRequestOrderItem)
-	return pieceOrderLess(
-		pieceOrderInput{
-			PieceRequestOrderState: me.state,
-			PieceRequestOrderKey:   me.key,
-		},
-		pieceOrderInput{
-			PieceRequestOrderState: otherConcrete.state,
-			PieceRequestOrderKey:   otherConcrete.key,
-		},
-	).Less()
+	return pieceOrderLess(me, otherConcrete).Less()
 }
 
 func (me *PieceRequestOrder) Add(key PieceRequestOrderKey, state PieceRequestOrderState) {
@@ -63,10 +54,17 @@ func (me *PieceRequestOrder) Add(key PieceRequestOrderKey, state PieceRequestOrd
 }
 
 func (me *PieceRequestOrder) Update(key PieceRequestOrderKey, state PieceRequestOrderState) {
-	item := me.existingItemForKey(key)
-	if item.state == state {
+	oldState, ok := me.keys[key]
+	if !ok {
+		panic("key should have been added already")
+	}
+	if state == oldState {
 		return
 	}
+	item := pieceRequestOrderItem{
+		key:   key,
+		state: oldState,
+	}
 	if me.tree.Delete(&item) == nil {
 		panic(fmt.Sprintf("%#v", key))
 	}