fix doubleGet issue caused by hasblock not announcing

License: MIT
Signed-off-by: Jeromy <why@ipfs.io>

exchange/bitswap/bitswap.go

@@ -264,6 +264,8 @@ func (bs *Bitswap) HasBlock(blk *blocks.Block) error {
 
 	bs.notifications.Publish(blk)
 
+	bs.engine.AddBlock(blk)
+
 	select {
 	case bs.newBlocks <- blk:
 		// send block off to be reprovided

exchange/bitswap/bitswap_test.go

@@ -335,6 +335,8 @@ func TestDoubleGet(t *testing.T) {
 		t.Fatal(err)
 	}
 
+	// ensure both requests make it into the wantlist at the same time
+	time.Sleep(time.Millisecond * 100)
 	cancel1()
 
 	_, ok := <-blkch1

exchange/bitswap/decision/engine.go

@@ -83,7 +83,7 @@ type Engine struct {
 
 	bs bstore.Blockstore
 
-	lock sync.RWMutex // protects the fields immediatly below
+	lock sync.Mutex // protects the fields immediatly below
 	// ledgerMap lists Ledgers by their Partner key.
 	ledgerMap map[peer.ID]*ledger
 }
@@ -178,8 +178,8 @@ func (e *Engine) Outbox() <-chan (<-chan *Envelope) {
 
 // Returns a slice of Peers with whom the local node has active sessions
 func (e *Engine) Peers() []peer.ID {
-	e.lock.RLock()
-	defer e.lock.RUnlock()
+	e.lock.Lock()
+	defer e.lock.Unlock()
 
 	response := make([]peer.ID, 0)
 	for _, ledger := range e.ledgerMap {
@@ -217,7 +217,7 @@ func (e *Engine) MessageReceived(p peer.ID, m bsmsg.BitSwapMessage) error {
 			e.peerRequestQueue.Remove(entry.Key, p)
 		} else {
 			log.Debugf("wants %s - %d", entry.Key, entry.Priority)
-			l.Wants(entry.Ctx, entry.Key, entry.Priority)
+			l.Wants(entry.Key, entry.Priority)
 			if exists, err := e.bs.Has(entry.Key); err == nil && exists {
 				e.peerRequestQueue.Push(entry.Entry, p)
 				newWorkExists = true
@@ -228,16 +228,32 @@ func (e *Engine) MessageReceived(p peer.ID, m bsmsg.BitSwapMessage) error {
 	for _, block := range m.Blocks() {
 		log.Debugf("got block %s %d bytes", block.Key(), len(block.Data))
 		l.ReceivedBytes(len(block.Data))
-		for _, l := range e.ledgerMap {
-			if entry, ok := l.WantListContains(block.Key()); ok {
-				e.peerRequestQueue.Push(entry, l.Partner)
-				newWorkExists = true
-			}
-		}
 	}
 	return nil
 }
 
+func (e *Engine) addBlock(block *blocks.Block) {
+	work := false
+
+	for _, l := range e.ledgerMap {
+		if entry, ok := l.WantListContains(block.Key()); ok {
+			e.peerRequestQueue.Push(entry, l.Partner)
+			work = true
+		}
+	}
+
+	if work {
+		e.signalNewWork()
+	}
+}
+
+func (e *Engine) AddBlock(block *blocks.Block) {
+	e.lock.Lock()
+	defer e.lock.Unlock()
+
+	e.addBlock(block)
+}
+
 // TODO add contents of m.WantList() to my local wantlist? NB: could introduce
 // race conditions where I send a message, but MessageSent gets handled after
 // MessageReceived. The information in the local wantlist could become

exchange/bitswap/decision/ledger.go

@@ -6,8 +6,6 @@ import (
 	key "github.com/ipfs/go-ipfs/blocks/key"
 	wl "github.com/ipfs/go-ipfs/exchange/bitswap/wantlist"
 	peer "gx/ipfs/QmZwZjMVGss5rqYsJVGy18gNbkTJffFyq2x1uJ4e4p3ZAt/go-libp2p-peer"
-
-	"gx/ipfs/QmZy2y8t9zQH2a1b8q2ZSLKp17ATuJoCNxxyMFG5qFExpt/go-net/context"
 )
 
 // keySet is just a convenient alias for maps of keys, where we only care
@@ -69,10 +67,9 @@ func (l *ledger) ReceivedBytes(n int) {
 	l.Accounting.BytesRecv += uint64(n)
 }
 
-// TODO: this needs to be different. We need timeouts.
-func (l *ledger) Wants(ctx context.Context, k key.Key, priority int) {
+func (l *ledger) Wants(k key.Key, priority int) {
 	log.Debugf("peer %s wants %s", l.Partner, k)
-	l.wantList.Add(ctx, k, priority)
+	l.wantList.Add(k, priority)
 }
 
 func (l *ledger) CancelWant(k key.Key) {

exchange/bitswap/wantlist/wantlist.go

@@ -22,11 +22,12 @@ type Wantlist struct {
 }
 
 type Entry struct {
-	// TODO consider making entries immutable so they can be shared safely and
-	// slices can be copied efficiently.
 	Key      key.Key
 	Priority int
-	Ctx      context.Context
+
+	Ctx    context.Context
+	cancel func()
+	RefCnt int
 }
 
 type entrySlice []Entry
@@ -47,10 +48,10 @@ func New() *Wantlist {
 	}
 }
 
-func (w *ThreadSafe) Add(ctx context.Context, k key.Key, priority int) {
+func (w *ThreadSafe) Add(k key.Key, priority int) {
 	w.lk.Lock()
 	defer w.lk.Unlock()
-	w.Wantlist.Add(ctx, k, priority)
+	w.Wantlist.Add(k, priority)
 }
 
 func (w *ThreadSafe) AddEntry(e Entry) {
@@ -93,14 +94,19 @@ func (w *Wantlist) Len() int {
 	return len(w.set)
 }
 
-func (w *Wantlist) Add(ctx context.Context, k key.Key, priority int) {
-	if _, ok := w.set[k]; ok {
+func (w *Wantlist) Add(k key.Key, priority int) {
+	if e, ok := w.set[k]; ok {
+		e.RefCnt++
 		return
 	}
+
+	ctx, cancel := context.WithCancel(context.Background())
 	w.set[k] = Entry{
 		Key:      k,
 		Priority: priority,
 		Ctx:      ctx,
+		cancel:   cancel,
+		RefCnt:   1,
 	}
 }
 
@@ -112,7 +118,18 @@ func (w *Wantlist) AddEntry(e Entry) {
 }
 
 func (w *Wantlist) Remove(k key.Key) {
-	delete(w.set, k)
+	e, ok := w.set[k]
+	if !ok {
+		return
+	}
+
+	e.RefCnt--
+	if e.RefCnt <= 0 {
+		delete(w.set, k)
+		if e.cancel != nil {
+			e.cancel()
+		}
+	}
 }
 
 func (w *Wantlist) Contains(k key.Key) (Entry, bool) {