diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc index 40bf9c65644..51b61ecb92c 100644 --- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc +++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc @@ -296,9 +296,8 @@ class GrpcLb : public LoadBalancingPolicy { // The channel for communicating with the LB server. grpc_channel* lb_channel_ = nullptr; - // Mutex to protect the channel to the LB server. This is used when - // processing a channelz request. - gpr_mu lb_channel_mu_; + // Uuid of the lb channel. Used for channelz. + gpr_atm lb_channel_uuid_ = 0; grpc_connectivity_state lb_channel_connectivity_; grpc_closure lb_channel_on_connectivity_changed_; // Are we already watching the LB channel's connectivity? @@ -986,7 +985,6 @@ GrpcLb::GrpcLb(const LoadBalancingPolicy::Args& args) .set_max_backoff(GRPC_GRPCLB_RECONNECT_MAX_BACKOFF_SECONDS * 1000)) { // Initialization. - gpr_mu_init(&lb_channel_mu_); GRPC_CLOSURE_INIT(&lb_channel_on_connectivity_changed_, &GrpcLb::OnBalancerChannelConnectivityChangedLocked, this, grpc_combiner_scheduler(args.combiner)); @@ -1023,7 +1021,6 @@ GrpcLb::GrpcLb(const LoadBalancingPolicy::Args& args) GrpcLb::~GrpcLb() { GPR_ASSERT(pending_picks_ == nullptr); - gpr_mu_destroy(&lb_channel_mu_); gpr_free((void*)server_name_); grpc_channel_args_destroy(args_); grpc_connectivity_state_destroy(&state_tracker_); @@ -1049,10 +1046,9 @@ void GrpcLb::ShutdownLocked() { // OnBalancerChannelConnectivityChangedLocked(), and we need to be // alive when that callback is invoked. if (lb_channel_ != nullptr) { - gpr_mu_lock(&lb_channel_mu_); grpc_channel_destroy(lb_channel_); lb_channel_ = nullptr; - gpr_mu_unlock(&lb_channel_mu_); + gpr_atm_no_barrier_store(&lb_channel_uuid_, 0); } grpc_connectivity_state_set(&state_tracker_, GRPC_CHANNEL_SHUTDOWN, GRPC_ERROR_REF(error), "grpclb_shutdown"); @@ -1207,14 +1203,12 @@ void GrpcLb::FillChildRefsForChannelz( channelz::ChildRefsList* child_subchannels, channelz::ChildRefsList* child_channels) { // delegate to the RoundRobin to fill the children subchannels. - rr_policy_->FillChildRefsForChannelz(child_subchannels, child_channels); - MutexLock lock(&lb_channel_mu_); - if (lb_channel_ != nullptr) { - grpc_core::channelz::ChannelNode* channel_node = - grpc_channel_get_channelz_node(lb_channel_); - if (channel_node != nullptr) { - child_channels->push_back(channel_node->uuid()); - } + if (rr_policy_ != nullptr) { + rr_policy_->FillChildRefsForChannelz(child_subchannels, child_channels); + } + gpr_atm uuid = gpr_atm_no_barrier_load(&lb_channel_uuid_); + if (uuid != 0) { + child_channels->push_back(uuid); } } @@ -1274,12 +1268,15 @@ void GrpcLb::ProcessChannelArgsLocked(const grpc_channel_args& args) { if (lb_channel_ == nullptr) { char* uri_str; gpr_asprintf(&uri_str, "fake:///%s", server_name_); - gpr_mu_lock(&lb_channel_mu_); lb_channel_ = grpc_client_channel_factory_create_channel( client_channel_factory(), uri_str, GRPC_CLIENT_CHANNEL_TYPE_LOAD_BALANCING, lb_channel_args); - gpr_mu_unlock(&lb_channel_mu_); GPR_ASSERT(lb_channel_ != nullptr); + grpc_core::channelz::ChannelNode* channel_node = + grpc_channel_get_channelz_node(lb_channel_); + if (channel_node != nullptr) { + gpr_atm_no_barrier_store(&lb_channel_uuid_, channel_node->uuid()); + } gpr_free(uri_str); } // Propagate updates to the LB channel (pick_first) through the fake