channelz: major cleanup / reorganization (#6969)

balancer/balancer.go

@@ -232,8 +232,8 @@ type BuildOptions struct {
 	// implementations which do not communicate with a remote load balancer
 	// server can ignore this field.
 	Authority string
-	// ChannelzParentID is the parent ClientConn's channelz ID.
-	ChannelzParentID *channelz.Identifier
+	// ChannelzParent is the parent ClientConn's channelz channel.
+	ChannelzParent channelz.Identifier
 	// CustomUserAgent is the custom user agent set on the parent ClientConn.
 	// The balancer should set the same custom user agent if it creates a
 	// ClientConn.

balancer/grpclb/grpclb_remote_balancer.go

@@ -246,7 +246,7 @@ func (lb *lbBalancer) newRemoteBalancerCCWrapper() error {
 	// Explicitly set pickfirst as the balancer.
 	dopts = append(dopts, grpc.WithDefaultServiceConfig(`{"loadBalancingPolicy":"pick_first"}`))
 	dopts = append(dopts, grpc.WithResolvers(lb.manualResolver))
-	dopts = append(dopts, grpc.WithChannelzParentID(lb.opt.ChannelzParentID))
+	dopts = append(dopts, grpc.WithChannelzParentID(lb.opt.ChannelzParent))
 
 	// Enable Keepalive for grpclb client.
 	dopts = append(dopts, grpc.WithKeepaliveParams(keepalive.ClientParameters{

balancer_wrapper.go

@@ -72,13 +72,13 @@ func newCCBalancerWrapper(cc *ClientConn) *ccBalancerWrapper {
 	ccb := &ccBalancerWrapper{
 		cc: cc,
 		opts: balancer.BuildOptions{
-			DialCreds:        cc.dopts.copts.TransportCredentials,
-			CredsBundle:      cc.dopts.copts.CredsBundle,
-			Dialer:           cc.dopts.copts.Dialer,
-			Authority:        cc.authority,
-			CustomUserAgent:  cc.dopts.copts.UserAgent,
-			ChannelzParentID: cc.channelzID,
-			Target:           cc.parsedTarget,
+			DialCreds:       cc.dopts.copts.TransportCredentials,
+			CredsBundle:     cc.dopts.copts.CredsBundle,
+			Dialer:          cc.dopts.copts.Dialer,
+			Authority:       cc.authority,
+			CustomUserAgent: cc.dopts.copts.UserAgent,
+			ChannelzParent:  cc.channelz,
+			Target:          cc.parsedTarget,
 		},
 		serializer:       grpcsync.NewCallbackSerializer(ctx),
 		serializerCancel: cancel,
@@ -155,14 +155,14 @@ func (ccb *ccBalancerWrapper) switchTo(name string) {
 func (ccb *ccBalancerWrapper) buildLoadBalancingPolicy(name string) {
 	builder := balancer.Get(name)
 	if builder == nil {
-		channelz.Warningf(logger, ccb.cc.channelzID, "Channel switches to new LB policy %q, since the specified LB policy %q was not registered", PickFirstBalancerName, name)
+		channelz.Warningf(logger, ccb.cc.channelz, "Channel switches to new LB policy %q, since the specified LB policy %q was not registered", PickFirstBalancerName, name)
 		builder = newPickfirstBuilder()
 	} else {
-		channelz.Infof(logger, ccb.cc.channelzID, "Channel switches to new LB policy %q", name)
+		channelz.Infof(logger, ccb.cc.channelz, "Channel switches to new LB policy %q", name)
 	}
 
 	if err := ccb.balancer.SwitchTo(builder); err != nil {
-		channelz.Errorf(logger, ccb.cc.channelzID, "Channel failed to build new LB policy %q: %v", name, err)
+		channelz.Errorf(logger, ccb.cc.channelz, "Channel failed to build new LB policy %q: %v", name, err)
 		return
 	}
 	ccb.curBalancerName = builder.Name()
@@ -175,7 +175,7 @@ func (ccb *ccBalancerWrapper) close() {
 	ccb.mu.Lock()
 	ccb.closed = true
 	ccb.mu.Unlock()
-	channelz.Info(logger, ccb.cc.channelzID, "ccBalancerWrapper: closing")
+	channelz.Info(logger, ccb.cc.channelz, "ccBalancerWrapper: closing")
 	ccb.serializer.Schedule(func(context.Context) {
 		if ccb.balancer == nil {
 			return
@@ -212,7 +212,7 @@ func (ccb *ccBalancerWrapper) NewSubConn(addrs []resolver.Address, opts balancer
 	}
 	ac, err := ccb.cc.newAddrConnLocked(addrs, opts)
 	if err != nil {
-		channelz.Warningf(logger, ccb.cc.channelzID, "acBalancerWrapper: NewSubConn: failed to newAddrConn: %v", err)
+		channelz.Warningf(logger, ccb.cc.channelz, "acBalancerWrapper: NewSubConn: failed to newAddrConn: %v", err)
 		return nil, err
 	}
 	acbw := &acBalancerWrapper{
@@ -304,7 +304,7 @@ func (acbw *acBalancerWrapper) updateState(s connectivity.State, err error) {
 }
 
 func (acbw *acBalancerWrapper) String() string {
-	return fmt.Sprintf("SubConn(id:%d)", acbw.ac.channelzID.Int())
+	return fmt.Sprintf("SubConn(id:%d)", acbw.ac.channelz.ID)
 }
 
 func (acbw *acBalancerWrapper) UpdateAddresses(addrs []resolver.Address) {

channelz/service/func_linux.go

@@ -33,6 +33,9 @@ func convertToPtypesDuration(sec int64, usec int64) *durpb.Duration {
 }
 
 func sockoptToProto(skopts *channelz.SocketOptionData) []*channelzpb.SocketOption {
+	if skopts == nil {
+		return nil
+	}
 	var opts []*channelzpb.SocketOption
 	if skopts.Linger != nil {
 		additional, err := anypb.New(&channelzpb.SocketOptionLinger{