all: Use new Go 1.19 atomic types (#8772)

lib/model/folder.go

@@ -13,7 +13,6 @@ import (
 	"math/rand"
 	"path/filepath"
 	"sort"
-	"sync/atomic"
 	"time"
 
 	"github.com/syncthing/syncthing/lib/config"
@@ -142,8 +141,8 @@ func newFolder(model *model, fset *db.FileSet, ignores *ignore.Matcher, cfg conf
 }
 
 func (f *folder) Serve(ctx context.Context) error {
-	atomic.AddInt32(&f.model.foldersRunning, 1)
-	defer atomic.AddInt32(&f.model.foldersRunning, -1)
+	f.model.foldersRunning.Add(1)
+	defer f.model.foldersRunning.Add(-1)
 
 	f.ctx = ctx
 

lib/model/model.go

@@ -23,6 +23,7 @@ import (
 	"runtime"
 	"strings"
 	stdsync "sync"
+	"sync/atomic"
 	"time"
 
 	"github.com/thejerf/suture/v4"
@@ -166,7 +167,7 @@ type model struct {
 	indexHandlers       map[protocol.DeviceID]*indexHandlerRegistry
 
 	// for testing only
-	foldersRunning int32
+	foldersRunning atomic.Int32
 }
 
 var _ config.Verifier = &model{}

lib/model/model_test.go

@@ -21,7 +21,6 @@ import (
 	"strconv"
 	"strings"
 	"sync"
-	"sync/atomic"
 	"testing"
 	"time"
 
@@ -3097,7 +3096,7 @@ func TestFolderRestartZombies(t *testing.T) {
 	m.ScanFolder("default")
 
 	// Check how many running folders we have running before the test.
-	if r := atomic.LoadInt32(&m.foldersRunning); r != 1 {
+	if r := m.foldersRunning.Load(); r != 1 {
 		t.Error("Expected one running folder, not", r)
 	}
 
@@ -3122,7 +3121,7 @@ func TestFolderRestartZombies(t *testing.T) {
 	wg.Wait()
 	// Make sure the folder is up and running, because we want to count it.
 	m.ScanFolder("default")
-	if r := atomic.LoadInt32(&m.foldersRunning); r != 1 {
+	if r := m.foldersRunning.Load(); r != 1 {
 		t.Error("Expected one running folder, not", r)
 	}
 }