remove waitgroup and apply a straightforward fix

accounts/keystore/account_cache.go

@@ -220,7 +220,6 @@ func (ac *accountCache) maybeReload() {
 	ac.watcher.start()
 	ac.throttle.Reset(minReloadInterval)
 	ac.mu.Unlock()
-	ac.watcher.startupWG.Wait()
 	ac.scanAccounts()
 }
 

accounts/keystore/account_cache_test.go

@@ -326,6 +326,11 @@ func TestUpdatedKeyfileContents(t *testing.T) {
 
 	// Create a temporary keystore to test with
 	dir := filepath.Join(os.TempDir(), fmt.Sprintf("eth-keystore-updatedkeyfilecontents-test-%d-%d", os.Getpid(), rand.Int()))
+
+	// Create the directory
+	os.MkdirAll(dir, 0700)
+	defer os.RemoveAll(dir)
+
 	ks := NewKeyStore(dir, LightScryptN, LightScryptP)
 
 	list := ks.Accounts()
@@ -335,9 +340,7 @@ func TestUpdatedKeyfileContents(t *testing.T) {
 	if !waitWatcherStart(ks) {
 		t.Fatal("keystore watcher didn't start in time")
 	}
-	// Create the directory and copy a key file into it.
-	os.MkdirAll(dir, 0700)
-	defer os.RemoveAll(dir)
+	// Copy a key file into it
 	file := filepath.Join(dir, "aaa")
 
 	// Place one of our testfiles in there

accounts/keystore/watch.go

@@ -21,7 +21,6 @@ package keystore
 
 import (
 	"os"
-	"sync"
 	"time"
 
 	"github.com/ethereum/go-ethereum/log"
@@ -34,14 +33,12 @@ type watcher struct {
 	runEnded bool // set to true when runloop ends
 	starting bool // set to true prior to runloop starting
 	quit     chan struct{}
-	startupWG sync.WaitGroup // wait for watcher loop to start
 }
 
 func newWatcher(ac *accountCache) *watcher {
 	return &watcher{
 		ac:   ac,
 		quit: make(chan struct{}),
-		startupWG: sync.WaitGroup{},
 	}
 }
 
@@ -55,7 +52,6 @@ func (w *watcher) start() {
 	if w.starting || w.running {
 		return
 	}
-	w.startupWG.Add(1)
 	w.starting = true
 	go w.loop()
 }
@@ -85,7 +81,6 @@ func (w *watcher) loop() {
 		if !os.IsNotExist(err) {
 			logger.Warn("Failed to watch keystore folder", "err", err)
 		}
-		w.startupWG.Done()
 		return
 	}
 
@@ -109,7 +104,6 @@ func (w *watcher) loop() {
 		<-debounce.C
 	}
 	defer debounce.Stop()
-	w.startupWG.Done()
 	for {
 		select {
 		case <-w.quit: