*: modernize: waitgroup

go install golang.org/x/tools/go/analysis/passes/modernize/cmd/modernize@latest
    modernize -waitgroup -fix ./...

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

core/metadata/db.go

@@ -426,11 +426,9 @@ func (m *DB) GarbageCollect(ctx context.Context) (gc.Stats, error) {
 	var wg sync.WaitGroup
 
 	// Flush events asynchronously after commit
-	wg.Add(1)
-	go func() {
+	wg.Go(func() {
 		m.publishEvents(events)
-		wg.Done()
-	}()
+	})
 
 	// Reset dirty. Truly don't need to be atomically stored inside of the wlock
 	// but we're using the atomic wrappers that guarantee atomic access everywhere.
@@ -490,13 +488,11 @@ func (m *DB) getMarked(ctx context.Context, c *gcContext) (map[gc.Node]struct{},
 			wg    sync.WaitGroup
 			roots = make(chan gc.Node)
 		)
-		wg.Add(1)
-		go func() {
-			defer wg.Done()
+		wg.Go(func() {
 			for n := range roots {
 				nodes = append(nodes, n)
 			}
-		}()
+		})
 		// Call roots
 		if err := c.scanRoots(ctx, tx, roots); err != nil { // From gc context
 			cancel()

internal/cri/io/container_io.go

@@ -174,8 +174,7 @@ func (c *ContainerIO) Attach(ctx context.Context, opts AttachOptions) {
 		// wrapper doesn't close the actual stdin, it only stops io.Copy.
 		// The actual stdin will be closed by stream server.
 		stdinStreamRC = cioutil.NewWrapReadCloser(opts.Stdin)
-		wg.Add(1)
-		go func() {
+		wg.Go(func() {
 			if _, err := io.Copy(c.stdin, stdinStreamRC); err != nil {
 				log.L.WithError(err).Errorf("Failed to pipe stdin for container attach %q", c.id)
 			}
@@ -197,8 +196,7 @@ func (c *ContainerIO) Attach(ctx context.Context, opts AttachOptions) {
 					c.stderrGroup.Remove(stderrKey)
 				}
 			}
-			wg.Done()
-		}()
+		})
 	}
 
 	attachStream := func(key string, close <-chan struct{}) {

internal/cri/io/exec_io.go

@@ -94,8 +94,7 @@ func (e *ExecIO) Attach(opts AttachOptions) <-chan struct{} {
 	var stdinStreamRC io.ReadCloser
 	if e.stdin != nil && opts.Stdin != nil {
 		stdinStreamRC = cioutil.NewWrapReadCloser(opts.Stdin)
-		wg.Add(1)
-		go func() {
+		wg.Go(func() {
 			if _, err := io.Copy(e.stdin, stdinStreamRC); err != nil {
 				log.L.WithError(err).Errorf("Failed to redirect stdin for container exec %q", e.id)
 			}
@@ -113,8 +112,7 @@ func (e *ExecIO) Attach(opts AttachOptions) <-chan struct{} {
 					e.stderr.Close()
 				}
 			}
-			wg.Done()
-		}()
+		})
 	}
 
 	attachOutput := func(t StreamType, stream io.WriteCloser, out io.ReadCloser) {

internal/cri/server/images/check.go

@@ -40,9 +40,7 @@ func (c *CRIImageService) CheckImages(ctx context.Context) error {
 	snapshotter := c.config.Snapshotter
 	var wg sync.WaitGroup
 	for _, i := range cImages {
-		wg.Add(1)
-		go func() {
-			defer wg.Done()
+		wg.Go(func() {
 			// TODO: Check platform/snapshot combination. Snapshot check should come first
 			ok, _, _, _, err := images.Check(ctx, i.ContentStore(), i.Target(), platforms.Default())
 			if err != nil {
@@ -69,7 +67,7 @@ func (c *CRIImageService) CheckImages(ctx context.Context) error {
 				return
 			}
 			log.G(ctx).Debugf("Loaded image %q", i.Name())
-		}()
+		})
 	}
 	wg.Wait()
 	return nil

internal/cri/server/podsandbox/types/podsandbox_test.go

@@ -46,25 +46,21 @@ func Test_PodSandbox(t *testing.T) {
 
 	exitAt := time.Now().Add(time.Second)
 	wg := sync.WaitGroup{}
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
+	wg.Go(func() {
 		ctx, cancel := context.WithTimeout(context.Background(), time.Millisecond*500)
 		defer cancel()
 		_, err := p.Wait(ctx)
 		assert.Equal(t, err, ctx.Err())
-	}()
+	})
 
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
+	wg.Go(func() {
 		exitStatus, err := p.Wait(context.Background())
 		assert.Equal(t, err, nil)
 		code, exitTime, err := exitStatus.Result()
 		assert.Equal(t, err, nil)
 		assert.Equal(t, code, uint32(128))
 		assert.Equal(t, exitTime, exitAt)
-	}()
+	})
 	time.Sleep(time.Second)
 	if err := p.Exit(uint32(128), exitAt); err != nil {
 		t.Fatalf("failed to set exit of pod sandbox %v", err)

internal/cri/server/sandbox_stats_list.go

@@ -39,9 +39,7 @@ func (c *criService) ListPodSandboxStats(
 
 	var wg sync.WaitGroup
 	for i, sandbox := range sandboxes {
-		wg.Add(1)
-		go func() {
-			defer wg.Done()
+		wg.Go(func() {
 			// issue 12279: this is tautologically true where interface is stubbed out.
 			sandboxStats, err := c.podSandboxStats(ctx, sandbox) //nolint: staticcheck
 			switch {
@@ -54,7 +52,7 @@ func (c *criService) ListPodSandboxStats(
 			default:
 				stats[i] = sandboxStats
 			}
-		}()
+		})
 	}
 	wg.Wait()
 

internal/kmutex/kmutex_test.go

@@ -148,10 +148,8 @@ func TestMultiAcquireOnSameKey(t *testing.T) {
 
 	var wg sync.WaitGroup
 	for range nproc {
-		wg.Add(1)
 
-		go func() {
-			defer wg.Done()
+		wg.Go(func() {
 
 			for range nloops {
 				km.Lock(ctx, key)
@@ -160,7 +158,7 @@ func TestMultiAcquireOnSameKey(t *testing.T) {
 
 				km.Unlock(key)
 			}
-		}()
+		})
 	}
 	km.Unlock(key)
 	wg.Wait()

pkg/cio/io_unix.go

@@ -73,27 +73,23 @@ func copyIO(fifos *FIFOSet, ioset *Streams) (*cio, error) {
 
 	var wg = &sync.WaitGroup{}
 	if fifos.Stdout != "" {
-		wg.Add(1)
-		go func() {
+		wg.Go(func() {
 			p := bufPool.Get().(*[]byte)
 			defer bufPool.Put(p)
 
 			io.CopyBuffer(ioset.Stdout, pipes.Stdout, *p)
 			pipes.Stdout.Close()
-			wg.Done()
-		}()
+		})
 	}
 
 	if !fifos.Terminal && fifos.Stderr != "" {
-		wg.Add(1)
-		go func() {
+		wg.Go(func() {
 			p := bufPool.Get().(*[]byte)
 			defer bufPool.Put(p)
 
 			io.CopyBuffer(ioset.Stderr, pipes.Stderr, *p)
 			pipes.Stderr.Close()
-			wg.Done()
-		}()
+		})
 	}
 	return &cio{
 		config:  fifos.Config,

plugins/restart/monitor.go

@@ -106,9 +106,7 @@ func (m *monitor) reconcile(ctx context.Context) error {
 	}
 	var wgNSLoop sync.WaitGroup
 	for _, name := range ns {
-		wgNSLoop.Add(1)
-		go func() {
-			defer wgNSLoop.Done()
+		wgNSLoop.Go(func() {
 			ctx := namespaces.WithNamespace(ctx, name)
 			changes, err := m.monitor(ctx)
 			if err != nil {
@@ -117,16 +115,14 @@ func (m *monitor) reconcile(ctx context.Context) error {
 			}
 			var wgChangesLoop sync.WaitGroup
 			for _, c := range changes {
-				wgChangesLoop.Add(1)
-				go func() {
-					defer wgChangesLoop.Done()
+				wgChangesLoop.Go(func() {
 					if err := c.apply(ctx, m.client); err != nil {
 						log.G(ctx).WithError(err).Error("apply change")
 					}
-				}()
+				})
 			}
 			wgChangesLoop.Wait()
-		}()
+		})
 	}
 	wgNSLoop.Wait()
 	return nil