Fix panic while stopping the cluster (#26580)

Signed-off-by: yah01 <yah2er0ne@outlook.com>

internal/rootcoord/proxy_manager.go

@@ -27,6 +27,7 @@ import (
 	v3rpc "go.etcd.io/etcd/api/v3/v3rpc/rpctypes"
 	clientv3 "go.etcd.io/etcd/client/v3"
 	"go.uber.org/zap"
+	"golang.org/x/sync/errgroup"
 
 	etcdkv "github.com/milvus-io/milvus/internal/kv/etcd"
 	"github.com/milvus-io/milvus/internal/util/sessionutil"
@@ -38,6 +39,7 @@ import (
 type proxyManager struct {
 	ctx              context.Context
 	cancel           context.CancelFunc
+	wg               errgroup.Group
 	lock             sync.Mutex
 	etcdCli          *clientv3.Client
 	initSessionsFunc []func([]*sessionutil.Session)
@@ -49,10 +51,10 @@ type proxyManager struct {
 // etcdEndpoints is the address list of etcd
 // fns are the custom getSessions function list
 func newProxyManager(ctx context.Context, client *clientv3.Client, fns ...func([]*sessionutil.Session)) *proxyManager {
-	ctx2, cancel2 := context.WithCancel(ctx)
+	ctx, cancel := context.WithCancel(ctx)
 	p := &proxyManager{
-		ctx:     ctx2,
-		cancel:  cancel2,
+		ctx:     ctx,
+		cancel:  cancel,
 		lock:    sync.Mutex{},
 		etcdCli: client,
 	}
@@ -97,7 +99,11 @@ func (p *proxyManager) WatchProxy() error {
 		clientv3.WithPrevKV(),
 		clientv3.WithRev(rev+1),
 	)
-	go p.startWatchEtcd(p.ctx, eventCh)
+
+	p.wg.Go(func() error {
+		p.startWatchEtcd(p.ctx, eventCh)
+		return nil
+	})
 	return nil
 }
 
@@ -203,4 +209,5 @@ func (p *proxyManager) getSessionsOnEtcd(ctx context.Context) ([]*sessionutil.Se
 // Stop stops the proxyManager
 func (p *proxyManager) Stop() {
 	p.cancel()
+	p.wg.Wait()
 }

internal/rootcoord/root_coord.go

@@ -714,6 +714,9 @@ func (c *Core) Stop() error {
 	c.UpdateStateCode(commonpb.StateCode_Abnormal)
 	c.stopExecutor()
 	c.stopScheduler()
+	if c.proxyManager != nil {
+		c.proxyManager.Stop()
+	}
 	c.cancelIfNotNil()
 	if c.quotaCenter != nil {
 		c.quotaCenter.stop()