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authorDaniel J Walsh <dwalsh@redhat.com>2022-07-11 10:03:44 -0400
committerMatthew Heon <matthew.heon@pm.me>2022-07-26 13:34:38 -0400
commit9c1de040b36483fed1c331c438d8bce5fd8fab58 (patch)
tree7423c50dd57336eb045fea31665f4a1fb808acab /vendor/google.golang.org/grpc/clientconn.go
parent03eaea8bbe4dc7791c2129d64321988d3ec12bb0 (diff)
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Vendor in containers/(storage,image, common, buildah)
Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>
Diffstat (limited to 'vendor/google.golang.org/grpc/clientconn.go')
-rw-r--r--vendor/google.golang.org/grpc/clientconn.go350
1 files changed, 151 insertions, 199 deletions
diff --git a/vendor/google.golang.org/grpc/clientconn.go b/vendor/google.golang.org/grpc/clientconn.go
index 28f09dc87..de6d41c23 100644
--- a/vendor/google.golang.org/grpc/clientconn.go
+++ b/vendor/google.golang.org/grpc/clientconn.go
@@ -79,7 +79,7 @@ var (
// errNoTransportSecurity indicates that there is no transport security
// being set for ClientConn. Users should either set one or explicitly
// call WithInsecure DialOption to disable security.
- errNoTransportSecurity = errors.New("grpc: no transport security set (use grpc.WithInsecure() explicitly or set credentials)")
+ errNoTransportSecurity = errors.New("grpc: no transport security set (use grpc.WithTransportCredentials(insecure.NewCredentials()) explicitly or set credentials)")
// errTransportCredsAndBundle indicates that creds bundle is used together
// with other individual Transport Credentials.
errTransportCredsAndBundle = errors.New("grpc: credentials.Bundle may not be used with individual TransportCredentials")
@@ -159,23 +159,20 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
}
}()
- if channelz.IsOn() {
- if cc.dopts.channelzParentID != 0 {
- cc.channelzID = channelz.RegisterChannel(&channelzChannel{cc}, cc.dopts.channelzParentID, target)
- channelz.AddTraceEvent(logger, cc.channelzID, 0, &channelz.TraceEventDesc{
- Desc: "Channel Created",
- Severity: channelz.CtInfo,
- Parent: &channelz.TraceEventDesc{
- Desc: fmt.Sprintf("Nested Channel(id:%d) created", cc.channelzID),
- Severity: channelz.CtInfo,
- },
- })
- } else {
- cc.channelzID = channelz.RegisterChannel(&channelzChannel{cc}, 0, target)
- channelz.Info(logger, cc.channelzID, "Channel Created")
+ pid := cc.dopts.channelzParentID
+ cc.channelzID = channelz.RegisterChannel(&channelzChannel{cc}, pid, target)
+ ted := &channelz.TraceEventDesc{
+ Desc: "Channel created",
+ Severity: channelz.CtInfo,
+ }
+ if cc.dopts.channelzParentID != nil {
+ ted.Parent = &channelz.TraceEventDesc{
+ Desc: fmt.Sprintf("Nested Channel(id:%d) created", cc.channelzID.Int()),
+ Severity: channelz.CtInfo,
}
- cc.csMgr.channelzID = cc.channelzID
}
+ channelz.AddTraceEvent(logger, cc.channelzID, 1, ted)
+ cc.csMgr.channelzID = cc.channelzID
if cc.dopts.copts.TransportCredentials == nil && cc.dopts.copts.CredsBundle == nil {
return nil, errNoTransportSecurity
@@ -281,7 +278,7 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
if creds := cc.dopts.copts.TransportCredentials; creds != nil {
credsClone = creds.Clone()
}
- cc.balancerBuildOpts = balancer.BuildOptions{
+ cc.balancerWrapper = newCCBalancerWrapper(cc, balancer.BuildOptions{
DialCreds: credsClone,
CredsBundle: cc.dopts.copts.CredsBundle,
Dialer: cc.dopts.copts.Dialer,
@@ -289,7 +286,7 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
CustomUserAgent: cc.dopts.copts.UserAgent,
ChannelzParentID: cc.channelzID,
Target: cc.parsedTarget,
- }
+ })
// Build the resolver.
rWrapper, err := newCCResolverWrapper(cc, resolverBuilder)
@@ -398,7 +395,7 @@ type connectivityStateManager struct {
mu sync.Mutex
state connectivity.State
notifyChan chan struct{}
- channelzID int64
+ channelzID *channelz.Identifier
}
// updateState updates the connectivity.State of ClientConn.
@@ -464,34 +461,36 @@ var _ ClientConnInterface = (*ClientConn)(nil)
// handshakes. It also handles errors on established connections by
// re-resolving the name and reconnecting.
type ClientConn struct {
- ctx context.Context
- cancel context.CancelFunc
-
- target string
- parsedTarget resolver.Target
- authority string
- dopts dialOptions
- csMgr *connectivityStateManager
-
- balancerBuildOpts balancer.BuildOptions
- blockingpicker *pickerWrapper
-
+ ctx context.Context // Initialized using the background context at dial time.
+ cancel context.CancelFunc // Cancelled on close.
+
+ // The following are initialized at dial time, and are read-only after that.
+ target string // User's dial target.
+ parsedTarget resolver.Target // See parseTargetAndFindResolver().
+ authority string // See determineAuthority().
+ dopts dialOptions // Default and user specified dial options.
+ channelzID *channelz.Identifier // Channelz identifier for the channel.
+ balancerWrapper *ccBalancerWrapper // Uses gracefulswitch.balancer underneath.
+
+ // The following provide their own synchronization, and therefore don't
+ // require cc.mu to be held to access them.
+ csMgr *connectivityStateManager
+ blockingpicker *pickerWrapper
safeConfigSelector iresolver.SafeConfigSelector
+ czData *channelzData
+ retryThrottler atomic.Value // Updated from service config.
- mu sync.RWMutex
- resolverWrapper *ccResolverWrapper
- sc *ServiceConfig
- conns map[*addrConn]struct{}
- // Keepalive parameter can be updated if a GoAway is received.
- mkp keepalive.ClientParameters
- curBalancerName string
- balancerWrapper *ccBalancerWrapper
- retryThrottler atomic.Value
-
+ // firstResolveEvent is used to track whether the name resolver sent us at
+ // least one update. RPCs block on this event.
firstResolveEvent *grpcsync.Event
- channelzID int64 // channelz unique identification number
- czData *channelzData
+ // mu protects the following fields.
+ // TODO: split mu so the same mutex isn't used for everything.
+ mu sync.RWMutex
+ resolverWrapper *ccResolverWrapper // Initialized in Dial; cleared in Close.
+ sc *ServiceConfig // Latest service config received from the resolver.
+ conns map[*addrConn]struct{} // Set to nil on close.
+ mkp keepalive.ClientParameters // May be updated upon receipt of a GoAway.
lceMu sync.Mutex // protects lastConnectionError
lastConnectionError error
@@ -536,14 +535,7 @@ func (cc *ClientConn) GetState() connectivity.State {
// Notice: This API is EXPERIMENTAL and may be changed or removed in a later
// release.
func (cc *ClientConn) Connect() {
- cc.mu.Lock()
- defer cc.mu.Unlock()
- if cc.balancerWrapper != nil && cc.balancerWrapper.exitIdle() {
- return
- }
- for ac := range cc.conns {
- go ac.connect()
- }
+ cc.balancerWrapper.exitIdle()
}
func (cc *ClientConn) scWatcher() {
@@ -623,9 +615,7 @@ func (cc *ClientConn) updateResolverState(s resolver.State, err error) error {
// with the new addresses.
cc.maybeApplyDefaultServiceConfig(nil)
- if cc.balancerWrapper != nil {
- cc.balancerWrapper.resolverError(err)
- }
+ cc.balancerWrapper.resolverError(err)
// No addresses are valid with err set; return early.
cc.mu.Unlock()
@@ -653,16 +643,10 @@ func (cc *ClientConn) updateResolverState(s resolver.State, err error) error {
cc.applyServiceConfigAndBalancer(sc, configSelector, s.Addresses)
} else {
ret = balancer.ErrBadResolverState
- if cc.balancerWrapper == nil {
- var err error
- if s.ServiceConfig.Err != nil {
- err = status.Errorf(codes.Unavailable, "error parsing service config: %v", s.ServiceConfig.Err)
- } else {
- err = status.Errorf(codes.Unavailable, "illegal service config type: %T", s.ServiceConfig.Config)
- }
- cc.safeConfigSelector.UpdateConfigSelector(&defaultConfigSelector{cc.sc})
- cc.blockingpicker.updatePicker(base.NewErrPicker(err))
- cc.csMgr.updateState(connectivity.TransientFailure)
+ if cc.sc == nil {
+ // Apply the failing LB only if we haven't received valid service config
+ // from the name resolver in the past.
+ cc.applyFailingLB(s.ServiceConfig)
cc.mu.Unlock()
return ret
}
@@ -670,24 +654,12 @@ func (cc *ClientConn) updateResolverState(s resolver.State, err error) error {
}
var balCfg serviceconfig.LoadBalancingConfig
- if cc.dopts.balancerBuilder == nil && cc.sc != nil && cc.sc.lbConfig != nil {
+ if cc.sc != nil && cc.sc.lbConfig != nil {
balCfg = cc.sc.lbConfig.cfg
}
-
- cbn := cc.curBalancerName
bw := cc.balancerWrapper
cc.mu.Unlock()
- if cbn != grpclbName {
- // Filter any grpclb addresses since we don't have the grpclb balancer.
- for i := 0; i < len(s.Addresses); {
- if s.Addresses[i].Type == resolver.GRPCLB {
- copy(s.Addresses[i:], s.Addresses[i+1:])
- s.Addresses = s.Addresses[:len(s.Addresses)-1]
- continue
- }
- i++
- }
- }
+
uccsErr := bw.updateClientConnState(&balancer.ClientConnState{ResolverState: s, BalancerConfig: balCfg})
if ret == nil {
ret = uccsErr // prefer ErrBadResolver state since any other error is
@@ -696,56 +668,28 @@ func (cc *ClientConn) updateResolverState(s resolver.State, err error) error {
return ret
}
-// switchBalancer starts the switching from current balancer to the balancer
-// with the given name.
-//
-// It will NOT send the current address list to the new balancer. If needed,
-// caller of this function should send address list to the new balancer after
-// this function returns.
+// applyFailingLB is akin to configuring an LB policy on the channel which
+// always fails RPCs. Here, an actual LB policy is not configured, but an always
+// erroring picker is configured, which returns errors with information about
+// what was invalid in the received service config. A config selector with no
+// service config is configured, and the connectivity state of the channel is
+// set to TransientFailure.
//
// Caller must hold cc.mu.
-func (cc *ClientConn) switchBalancer(name string) {
- if strings.EqualFold(cc.curBalancerName, name) {
- return
- }
-
- channelz.Infof(logger, cc.channelzID, "ClientConn switching balancer to %q", name)
- if cc.dopts.balancerBuilder != nil {
- channelz.Info(logger, cc.channelzID, "ignoring balancer switching: Balancer DialOption used instead")
- return
- }
- if cc.balancerWrapper != nil {
- // Don't hold cc.mu while closing the balancers. The balancers may call
- // methods that require cc.mu (e.g. cc.NewSubConn()). Holding the mutex
- // would cause a deadlock in that case.
- cc.mu.Unlock()
- cc.balancerWrapper.close()
- cc.mu.Lock()
- }
-
- builder := balancer.Get(name)
- if builder == nil {
- channelz.Warningf(logger, cc.channelzID, "Channel switches to new LB policy %q due to fallback from invalid balancer name", PickFirstBalancerName)
- channelz.Infof(logger, cc.channelzID, "failed to get balancer builder for: %v, using pick_first instead", name)
- builder = newPickfirstBuilder()
+func (cc *ClientConn) applyFailingLB(sc *serviceconfig.ParseResult) {
+ var err error
+ if sc.Err != nil {
+ err = status.Errorf(codes.Unavailable, "error parsing service config: %v", sc.Err)
} else {
- channelz.Infof(logger, cc.channelzID, "Channel switches to new LB policy %q", name)
+ err = status.Errorf(codes.Unavailable, "illegal service config type: %T", sc.Config)
}
-
- cc.curBalancerName = builder.Name()
- cc.balancerWrapper = newCCBalancerWrapper(cc, builder, cc.balancerBuildOpts)
+ cc.safeConfigSelector.UpdateConfigSelector(&defaultConfigSelector{nil})
+ cc.blockingpicker.updatePicker(base.NewErrPicker(err))
+ cc.csMgr.updateState(connectivity.TransientFailure)
}
func (cc *ClientConn) handleSubConnStateChange(sc balancer.SubConn, s connectivity.State, err error) {
- cc.mu.Lock()
- if cc.conns == nil {
- cc.mu.Unlock()
- return
- }
- // TODO(bar switching) send updates to all balancer wrappers when balancer
- // gracefully switching is supported.
- cc.balancerWrapper.handleSubConnStateChange(sc, s, err)
- cc.mu.Unlock()
+ cc.balancerWrapper.updateSubConnState(sc, s, err)
}
// newAddrConn creates an addrConn for addrs and adds it to cc.conns.
@@ -768,17 +712,21 @@ func (cc *ClientConn) newAddrConn(addrs []resolver.Address, opts balancer.NewSub
cc.mu.Unlock()
return nil, ErrClientConnClosing
}
- if channelz.IsOn() {
- ac.channelzID = channelz.RegisterSubChannel(ac, cc.channelzID, "")
- channelz.AddTraceEvent(logger, ac.channelzID, 0, &channelz.TraceEventDesc{
- Desc: "Subchannel Created",
- Severity: channelz.CtInfo,
- Parent: &channelz.TraceEventDesc{
- Desc: fmt.Sprintf("Subchannel(id:%d) created", ac.channelzID),
- Severity: channelz.CtInfo,
- },
- })
+
+ var err error
+ ac.channelzID, err = channelz.RegisterSubChannel(ac, cc.channelzID, "")
+ if err != nil {
+ return nil, err
}
+ channelz.AddTraceEvent(logger, ac.channelzID, 0, &channelz.TraceEventDesc{
+ Desc: "Subchannel created",
+ Severity: channelz.CtInfo,
+ Parent: &channelz.TraceEventDesc{
+ Desc: fmt.Sprintf("Subchannel(id:%d) created", ac.channelzID.Int()),
+ Severity: channelz.CtInfo,
+ },
+ })
+
cc.conns[ac] = struct{}{}
cc.mu.Unlock()
return ac, nil
@@ -853,16 +801,31 @@ func (ac *addrConn) connect() error {
return nil
}
+func equalAddresses(a, b []resolver.Address) bool {
+ if len(a) != len(b) {
+ return false
+ }
+ for i, v := range a {
+ if !v.Equal(b[i]) {
+ return false
+ }
+ }
+ return true
+}
+
// tryUpdateAddrs tries to update ac.addrs with the new addresses list.
//
-// If ac is Connecting, it returns false. The caller should tear down the ac and
-// create a new one. Note that the backoff will be reset when this happens.
-//
// If ac is TransientFailure, it updates ac.addrs and returns true. The updated
// addresses will be picked up by retry in the next iteration after backoff.
//
// If ac is Shutdown or Idle, it updates ac.addrs and returns true.
//
+// If the addresses is the same as the old list, it does nothing and returns
+// true.
+//
+// If ac is Connecting, it returns false. The caller should tear down the ac and
+// create a new one. Note that the backoff will be reset when this happens.
+//
// If ac is Ready, it checks whether current connected address of ac is in the
// new addrs list.
// - If true, it updates ac.addrs and returns true. The ac will keep using
@@ -879,6 +842,10 @@ func (ac *addrConn) tryUpdateAddrs(addrs []resolver.Address) bool {
return true
}
+ if equalAddresses(ac.addrs, addrs) {
+ return true
+ }
+
if ac.state == connectivity.Connecting {
return false
}
@@ -959,14 +926,10 @@ func (cc *ClientConn) healthCheckConfig() *healthCheckConfig {
}
func (cc *ClientConn) getTransport(ctx context.Context, failfast bool, method string) (transport.ClientTransport, func(balancer.DoneInfo), error) {
- t, done, err := cc.blockingpicker.pick(ctx, failfast, balancer.PickInfo{
+ return cc.blockingpicker.pick(ctx, failfast, balancer.PickInfo{
Ctx: ctx,
FullMethodName: method,
})
- if err != nil {
- return nil, nil, toRPCErr(err)
- }
- return t, done, nil
}
func (cc *ClientConn) applyServiceConfigAndBalancer(sc *ServiceConfig, configSelector iresolver.ConfigSelector, addrs []resolver.Address) {
@@ -991,35 +954,26 @@ func (cc *ClientConn) applyServiceConfigAndBalancer(sc *ServiceConfig, configSel
cc.retryThrottler.Store((*retryThrottler)(nil))
}
- if cc.dopts.balancerBuilder == nil {
- // Only look at balancer types and switch balancer if balancer dial
- // option is not set.
- var newBalancerName string
- if cc.sc != nil && cc.sc.lbConfig != nil {
- newBalancerName = cc.sc.lbConfig.name
- } else {
- var isGRPCLB bool
- for _, a := range addrs {
- if a.Type == resolver.GRPCLB {
- isGRPCLB = true
- break
- }
- }
- if isGRPCLB {
- newBalancerName = grpclbName
- } else if cc.sc != nil && cc.sc.LB != nil {
- newBalancerName = *cc.sc.LB
- } else {
- newBalancerName = PickFirstBalancerName
+ var newBalancerName string
+ if cc.sc != nil && cc.sc.lbConfig != nil {
+ newBalancerName = cc.sc.lbConfig.name
+ } else {
+ var isGRPCLB bool
+ for _, a := range addrs {
+ if a.Type == resolver.GRPCLB {
+ isGRPCLB = true
+ break
}
}
- cc.switchBalancer(newBalancerName)
- } else if cc.balancerWrapper == nil {
- // Balancer dial option was set, and this is the first time handling
- // resolved addresses. Build a balancer with dopts.balancerBuilder.
- cc.curBalancerName = cc.dopts.balancerBuilder.Name()
- cc.balancerWrapper = newCCBalancerWrapper(cc, cc.dopts.balancerBuilder, cc.balancerBuildOpts)
+ if isGRPCLB {
+ newBalancerName = grpclbName
+ } else if cc.sc != nil && cc.sc.LB != nil {
+ newBalancerName = *cc.sc.LB
+ } else {
+ newBalancerName = PickFirstBalancerName
+ }
}
+ cc.balancerWrapper.switchTo(newBalancerName)
}
func (cc *ClientConn) resolveNow(o resolver.ResolveNowOptions) {
@@ -1070,11 +1024,11 @@ func (cc *ClientConn) Close() error {
rWrapper := cc.resolverWrapper
cc.resolverWrapper = nil
bWrapper := cc.balancerWrapper
- cc.balancerWrapper = nil
cc.mu.Unlock()
+ // The order of closing matters here since the balancer wrapper assumes the
+ // picker is closed before it is closed.
cc.blockingpicker.close()
-
if bWrapper != nil {
bWrapper.close()
}
@@ -1085,22 +1039,22 @@ func (cc *ClientConn) Close() error {
for ac := range conns {
ac.tearDown(ErrClientConnClosing)
}
- if channelz.IsOn() {
- ted := &channelz.TraceEventDesc{
- Desc: "Channel Deleted",
+ ted := &channelz.TraceEventDesc{
+ Desc: "Channel deleted",
+ Severity: channelz.CtInfo,
+ }
+ if cc.dopts.channelzParentID != nil {
+ ted.Parent = &channelz.TraceEventDesc{
+ Desc: fmt.Sprintf("Nested channel(id:%d) deleted", cc.channelzID.Int()),
Severity: channelz.CtInfo,
}
- if cc.dopts.channelzParentID != 0 {
- ted.Parent = &channelz.TraceEventDesc{
- Desc: fmt.Sprintf("Nested channel(id:%d) deleted", cc.channelzID),
- Severity: channelz.CtInfo,
- }
- }
- channelz.AddTraceEvent(logger, cc.channelzID, 0, ted)
- // TraceEvent needs to be called before RemoveEntry, as TraceEvent may add trace reference to
- // the entity being deleted, and thus prevent it from being deleted right away.
- channelz.RemoveEntry(cc.channelzID)
}
+ channelz.AddTraceEvent(logger, cc.channelzID, 0, ted)
+ // TraceEvent needs to be called before RemoveEntry, as TraceEvent may add
+ // trace reference to the entity being deleted, and thus prevent it from being
+ // deleted right away.
+ channelz.RemoveEntry(cc.channelzID)
+
return nil
}
@@ -1130,7 +1084,7 @@ type addrConn struct {
backoffIdx int // Needs to be stateful for resetConnectBackoff.
resetBackoff chan struct{}
- channelzID int64 // channelz unique identification number.
+ channelzID *channelz.Identifier
czData *channelzData
}
@@ -1284,6 +1238,7 @@ func (ac *addrConn) createTransport(addr resolver.Address, copts transport.Conne
ac.mu.Lock()
defer ac.mu.Unlock()
defer connClosed.Fire()
+ defer hcancel()
if !hcStarted || hctx.Err() != nil {
// We didn't start the health check or set the state to READY, so
// no need to do anything else here.
@@ -1294,7 +1249,6 @@ func (ac *addrConn) createTransport(addr resolver.Address, copts transport.Conne
// state, since there may be a new transport in this addrConn.
return
}
- hcancel()
ac.transport = nil
// Refresh the name resolver
ac.cc.resolveNow(resolver.ResolveNowOptions{})
@@ -1312,14 +1266,13 @@ func (ac *addrConn) createTransport(addr resolver.Address, copts transport.Conne
connectCtx, cancel := context.WithDeadline(ac.ctx, connectDeadline)
defer cancel()
- if channelz.IsOn() {
- copts.ChannelzParentID = ac.channelzID
- }
+ copts.ChannelzParentID = ac.channelzID
newTr, err := transport.NewClientTransport(connectCtx, ac.cc.ctx, addr, copts, func() { prefaceReceived.Fire() }, onGoAway, onClose)
if err != nil {
// newTr is either nil, or closed.
- channelz.Warningf(logger, ac.channelzID, "grpc: addrConn.createTransport failed to connect to %v. Err: %v", addr, err)
+ hcancel()
+ channelz.Warningf(logger, ac.channelzID, "grpc: addrConn.createTransport failed to connect to %s. Err: %v", addr, err)
return err
}
@@ -1332,7 +1285,7 @@ func (ac *addrConn) createTransport(addr resolver.Address, copts transport.Conne
newTr.Close(transport.ErrConnClosing)
if connectCtx.Err() == context.DeadlineExceeded {
err := errors.New("failed to receive server preface within timeout")
- channelz.Warningf(logger, ac.channelzID, "grpc: addrConn.createTransport failed to connect to %v: %v", addr, err)
+ channelz.Warningf(logger, ac.channelzID, "grpc: addrConn.createTransport failed to connect to %s: %v", addr, err)
return err
}
return nil
@@ -1497,19 +1450,18 @@ func (ac *addrConn) tearDown(err error) {
curTr.GracefulClose()
ac.mu.Lock()
}
- if channelz.IsOn() {
- channelz.AddTraceEvent(logger, ac.channelzID, 0, &channelz.TraceEventDesc{
- Desc: "Subchannel Deleted",
+ channelz.AddTraceEvent(logger, ac.channelzID, 0, &channelz.TraceEventDesc{
+ Desc: "Subchannel deleted",
+ Severity: channelz.CtInfo,
+ Parent: &channelz.TraceEventDesc{
+ Desc: fmt.Sprintf("Subchannel(id:%d) deleted", ac.channelzID.Int()),
Severity: channelz.CtInfo,
- Parent: &channelz.TraceEventDesc{
- Desc: fmt.Sprintf("Subchanel(id:%d) deleted", ac.channelzID),
- Severity: channelz.CtInfo,
- },
- })
- // TraceEvent needs to be called before RemoveEntry, as TraceEvent may add trace reference to
- // the entity being deleted, and thus prevent it from being deleted right away.
- channelz.RemoveEntry(ac.channelzID)
- }
+ },
+ })
+ // TraceEvent needs to be called before RemoveEntry, as TraceEvent may add
+ // trace reference to the entity being deleted, and thus prevent it from
+ // being deleted right away.
+ channelz.RemoveEntry(ac.channelzID)
ac.mu.Unlock()
}