[latest-17.0](vitessio#4549): CherryPick(vitessio#15365): CI: Address…

… data races on memorytopo Conn.closed (vitessio#4555)

* backport of 4549

* Fix import conflict

Signed-off-by: Matt Lord <mattalord@gmail.com>

---------

Signed-off-by: Matt Lord <mattalord@gmail.com>
Co-authored-by: Matt Lord <mattalord@gmail.com>

go/vt/topo/memorytopo/election.go

@@ -28,7 +28,7 @@ import (
 func (c *Conn) NewLeaderParticipation(name, id string) (topo.LeaderParticipation, error) {
 	c.factory.callstats.Add([]string{"NewLeaderParticipation"}, 1)
 
-	if c.closed {
+	if c.closed.Load() {
 		return nil, ErrConnectionClosed
 	}
 
@@ -74,7 +74,7 @@ type cLeaderParticipation struct {
 
 // WaitForLeadership is part of the topo.LeaderParticipation interface.
 func (mp *cLeaderParticipation) WaitForLeadership() (context.Context, error) {
-	if mp.c.closed {
+	if mp.c.closed.Load() {
 		return nil, ErrConnectionClosed
 	}
 
@@ -122,7 +122,7 @@ func (mp *cLeaderParticipation) Stop() {
 
 // GetCurrentLeaderID is part of the topo.LeaderParticipation interface
 func (mp *cLeaderParticipation) GetCurrentLeaderID(ctx context.Context) (string, error) {
-	if mp.c.closed {
+	if mp.c.closed.Load() {
 		return "", ErrConnectionClosed
 	}
 
@@ -141,7 +141,7 @@ func (mp *cLeaderParticipation) GetCurrentLeaderID(ctx context.Context) (string,
 
 // WaitForNewLeader is part of the topo.LeaderParticipation interface
 func (mp *cLeaderParticipation) WaitForNewLeader(ctx context.Context) (<-chan string, error) {
-	if mp.c.closed {
+	if mp.c.closed.Load() {
 		return nil, ErrConnectionClosed
 	}
 

go/vt/topo/memorytopo/lock.go

@@ -116,7 +116,7 @@ func (ld *memoryTopoLockDescriptor) Unlock(ctx context.Context) error {
 }
 
 func (c *Conn) unlock(ctx context.Context, dirPath string) error {
-	if c.closed {
+	if c.closed.Load() {
 		return ErrConnectionClosed
 	}
 

go/vt/topo/memorytopo/memorytopo.go

@@ -25,6 +25,7 @@ import (
 	"math/rand"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"vitess.io/vitess/go/stats"
@@ -135,13 +136,13 @@ type Conn struct {
 	factory    *Factory
 	cell       string
 	serverAddr string
-	closed     bool
+	closed     atomic.Bool
 }
 
 // dial returns immediately, unless the Conn points to the sentinel
 // UnreachableServerAddr, in which case it will block until the context expires.
 func (c *Conn) dial(ctx context.Context) error {
-	if c.closed {
+	if c.closed.Load() {
 		return ErrConnectionClosed
 	}
 	if c.serverAddr == UnreachableServerAddr {
@@ -154,7 +155,7 @@ func (c *Conn) dial(ctx context.Context) error {
 // Close is part of the topo.Conn interface.
 func (c *Conn) Close() {
 	c.factory.callstats.Add([]string{"Close"}, 1)
-	c.closed = true
+	c.closed.Store(true)
 }
 
 type watch struct {

go/vt/topo/memorytopo/watch.go

@@ -27,7 +27,7 @@ import (
 func (c *Conn) Watch(ctx context.Context, filePath string) (*topo.WatchData, <-chan *topo.WatchData, error) {
 	c.factory.callstats.Add([]string{"Watch"}, 1)
 
-	if c.closed {
+	if c.closed.Load() {
 		return nil, nil, ErrConnectionClosed
 	}
 
@@ -79,7 +79,7 @@ func (c *Conn) Watch(ctx context.Context, filePath string) (*topo.WatchData, <-c
 func (c *Conn) WatchRecursive(ctx context.Context, dirpath string) ([]*topo.WatchDataRecursive, <-chan *topo.WatchDataRecursive, error) {
 	c.factory.callstats.Add([]string{"WatchRecursive"}, 1)
 
-	if c.closed {
+	if c.closed.Load() {
 		return nil, nil, ErrConnectionClosed
 	}