| /* |
| * |
| * Copyright 2015 gRPC authors. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| */ |
| |
| #include <grpc/support/port_platform.h> |
| |
| #include "src/core/ext/filters/client_channel/lb_policy.h" |
| |
| #include "src/core/ext/filters/client_channel/lb_policy_registry.h" |
| #include "src/core/lib/iomgr/combiner.h" |
| |
| namespace grpc_core { |
| |
| DebugOnlyTraceFlag grpc_trace_lb_policy_refcount(false, "lb_policy_refcount"); |
| |
| // |
| // LoadBalancingPolicy |
| // |
| |
| LoadBalancingPolicy::LoadBalancingPolicy(Args args, intptr_t initial_refcount) |
| : InternallyRefCounted( |
| GRPC_TRACE_FLAG_ENABLED(grpc_trace_lb_policy_refcount) |
| ? "LoadBalancingPolicy" |
| : nullptr, |
| initial_refcount), |
| work_serializer_(std::move(args.work_serializer)), |
| interested_parties_(grpc_pollset_set_create()), |
| channel_control_helper_(std::move(args.channel_control_helper)) {} |
| |
| LoadBalancingPolicy::~LoadBalancingPolicy() { |
| grpc_pollset_set_destroy(interested_parties_); |
| } |
| |
| void LoadBalancingPolicy::Orphan() { |
| ShutdownLocked(); |
| Unref(DEBUG_LOCATION, "Orphan"); |
| } |
| |
| // |
| // LoadBalancingPolicy::UpdateArgs |
| // |
| |
| LoadBalancingPolicy::UpdateArgs::UpdateArgs(const UpdateArgs& other) { |
| addresses = other.addresses; |
| config = other.config; |
| args = grpc_channel_args_copy(other.args); |
| } |
| |
| LoadBalancingPolicy::UpdateArgs::UpdateArgs(UpdateArgs&& other) noexcept { |
| addresses = std::move(other.addresses); |
| config = std::move(other.config); |
| // TODO(roth): Use std::move() once channel args is converted to C++. |
| args = other.args; |
| other.args = nullptr; |
| } |
| |
| LoadBalancingPolicy::UpdateArgs& LoadBalancingPolicy::UpdateArgs::operator=( |
| const UpdateArgs& other) { |
| if (&other == this) { |
| return *this; |
| } |
| addresses = other.addresses; |
| config = other.config; |
| grpc_channel_args_destroy(args); |
| args = grpc_channel_args_copy(other.args); |
| return *this; |
| } |
| |
| LoadBalancingPolicy::UpdateArgs& LoadBalancingPolicy::UpdateArgs::operator=( |
| UpdateArgs&& other) noexcept { |
| addresses = std::move(other.addresses); |
| config = std::move(other.config); |
| // TODO(roth): Use std::move() once channel args is converted to C++. |
| grpc_channel_args_destroy(args); |
| args = other.args; |
| other.args = nullptr; |
| return *this; |
| } |
| |
| // |
| // LoadBalancingPolicy::QueuePicker |
| // |
| |
| LoadBalancingPolicy::PickResult LoadBalancingPolicy::QueuePicker::Pick( |
| PickArgs /*args*/) { |
| // We invoke the parent's ExitIdleLocked() via a closure instead |
| // of doing it directly here, for two reasons: |
| // 1. ExitIdleLocked() may cause the policy's state to change and |
| // a new picker to be delivered to the channel. If that new |
| // picker is delivered before ExitIdleLocked() returns, then by |
| // the time this function returns, the pick will already have |
| // been processed, and we'll be trying to re-process the same |
| // pick again, leading to a crash. |
| // 2. We are currently running in the data plane mutex, but we |
| // need to bounce into the control plane work_serializer to call |
| // ExitIdleLocked(). |
| if (!exit_idle_called_ && parent_ != nullptr) { |
| exit_idle_called_ = true; |
| auto* parent = parent_->Ref().release(); // ref held by lambda. |
| ExecCtx::Run(DEBUG_LOCATION, |
| GRPC_CLOSURE_CREATE( |
| [](void* arg, grpc_error_handle /*error*/) { |
| auto* parent = static_cast<LoadBalancingPolicy*>(arg); |
| parent->work_serializer()->Run( |
| [parent]() { |
| parent->ExitIdleLocked(); |
| parent->Unref(); |
| }, |
| DEBUG_LOCATION); |
| }, |
| parent, nullptr), |
| GRPC_ERROR_NONE); |
| } |
| PickResult result; |
| result.type = PickResult::PICK_QUEUE; |
| return result; |
| } |
| |
| // |
| // LoadBalancingPolicy::TransientFailurePicker |
| // |
| |
| LoadBalancingPolicy::PickResult |
| LoadBalancingPolicy::TransientFailurePicker::Pick(PickArgs /*args*/) { |
| PickResult result; |
| result.type = PickResult::PICK_FAILED; |
| result.error = GRPC_ERROR_REF(error_); |
| return result; |
| } |
| |
| } // namespace grpc_core |