From 4bd1ce868f4ea4b76a378a9efa33d7a4255e26d4 Mon Sep 17 00:00:00 2001
From: Egon Elbre <egonelbre@gmail.com>
Date: Mon, 23 Sep 2019 22:14:39 +0300
Subject: [PATCH] satellite/metainfo: close loop separately to avoid logical
 races (#3100)

---
 satellite/metainfo/loop.go      | 8 ++++++--
 satellite/metainfo/loop_test.go | 4 ++++
 satellite/peer.go               | 9 ++++++---
 3 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/satellite/metainfo/loop.go b/satellite/metainfo/loop.go
index 5cd50a738..5f59b780c 100644
--- a/satellite/metainfo/loop.go
+++ b/satellite/metainfo/loop.go
@@ -121,8 +121,6 @@ func (loop *Loop) Join(ctx context.Context, observer Observer) (err error) {
 func (loop *Loop) Run(ctx context.Context) (err error) {
 	defer mon.Task()(&ctx)(&err)
 
-	defer close(loop.done)
-
 	for {
 		err := loop.runOnce(ctx)
 		if err != nil {
@@ -131,6 +129,12 @@ func (loop *Loop) Run(ctx context.Context) (err error) {
 	}
 }
 
+// Close closes the looping services.
+func (loop *Loop) Close() (err error) {
+	close(loop.done)
+	return nil
+}
+
 // runOnce goes through metainfo one time and sends information to observers.
 func (loop *Loop) runOnce(ctx context.Context) (err error) {
 	defer mon.Task()(&ctx)(&err)
diff --git a/satellite/metainfo/loop_test.go b/satellite/metainfo/loop_test.go
index f2b3db93f..ab9d760e6 100644
--- a/satellite/metainfo/loop_test.go
+++ b/satellite/metainfo/loop_test.go
@@ -223,6 +223,7 @@ func TestLoopCancel(t *testing.T) {
 		metaLoop := metainfo.NewLoop(metainfo.LoopConfig{
 			CoalesceDuration: 1 * time.Second,
 		}, satellite.Metainfo.Service)
+
 		// create a cancelable context to pass into metaLoop.Run
 		loopCtx, cancel := context.WithCancel(ctx)
 
@@ -270,6 +271,9 @@ func TestLoopCancel(t *testing.T) {
 		err := group.Wait()
 		require.NoError(t, err)
 
+		err = metaLoop.Close()
+		require.NoError(t, err)
+
 		obs3 := newTestObserver(nil)
 		err = metaLoop.Join(ctx, obs3)
 		require.Error(t, err)
diff --git a/satellite/peer.go b/satellite/peer.go
index 2b5673384..5c34a991a 100644
--- a/satellite/peer.go
+++ b/satellite/peer.go
@@ -670,6 +670,9 @@ func (peer *Peer) Run(ctx context.Context) (err error) {
 
 	group, ctx := errgroup.WithContext(ctx)
 
+	group.Go(func() error {
+		return errs2.IgnoreCanceled(peer.Metainfo.Loop.Run(ctx))
+	})
 	group.Go(func() error {
 		return errs2.IgnoreCanceled(peer.Version.Run(ctx))
 	})
@@ -679,9 +682,6 @@ func (peer *Peer) Run(ctx context.Context) (err error) {
 	group.Go(func() error {
 		return errs2.IgnoreCanceled(peer.Repair.Checker.Run(ctx))
 	})
-	group.Go(func() error {
-		return errs2.IgnoreCanceled(peer.Metainfo.Loop.Run(ctx))
-	})
 	group.Go(func() error {
 		return errs2.IgnoreCanceled(peer.Repair.Repairer.Run(ctx))
 	})
@@ -788,6 +788,9 @@ func (peer *Peer) Close() error {
 	if peer.Overlay.Service != nil {
 		errlist.Add(peer.Overlay.Service.Close())
 	}
+	if peer.Metainfo.Loop != nil {
+		errlist.Add(peer.Metainfo.Loop.Close())
+	}
 
 	return errlist.Err()
 }