Craig Tiller
11 months ago
parent
a5cbcd8c7e
commit
bca9cad9f7
10 changed files with 898 additions and 824 deletions
File diff suppressed because it is too large
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// Copyright 2024 gRPC authors.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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#include "src/core/client_channel/lb_call_tracing_filter.h" |
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#include "lb_call_tracing_filter.h" |
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namespace grpc_core { |
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const NoInterceptor LbCallTracingFilter::Call::OnClientToServerMessage; |
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const NoInterceptor LbCallTracingFilter::Call::OnServerToClientMessage; |
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void LbCallTracingFilter::Call::OnClientInitialMetadata( |
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ClientMetadata& metadata) { |
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auto* tracer = GetCallAttemptTracerFromContext(); |
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if (tracer == nullptr) return; |
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tracer->RecordSendInitialMetadata(&metadata); |
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} |
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void LbCallTracingFilter::Call::OnServerInitialMetadata( |
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ServerMetadata& metadata) { |
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auto* tracer = GetCallAttemptTracerFromContext(); |
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if (tracer == nullptr) return; |
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tracer->RecordReceivedInitialMetadata(&metadata); |
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// Save peer string for later use.
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Slice* peer_string = metadata.get_pointer(PeerString()); |
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if (peer_string != nullptr) peer_string_ = peer_string->Ref(); |
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} |
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static const NoInterceptor OnClientToServerMessage; |
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static const NoInterceptor OnServerToClientMessage; |
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void LbCallTracingFilter::Call::OnClientToServerHalfClose() { |
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auto* tracer = GetCallAttemptTracerFromContext(); |
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if (tracer == nullptr) return; |
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// TODO(roth): Change CallTracer API to not pass metadata
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// batch to this method, since the batch is always empty.
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grpc_metadata_batch metadata; |
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tracer->RecordSendTrailingMetadata(&metadata); |
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} |
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void LbCallTracingFilter::Call::OnServerTrailingMetadata( |
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ServerMetadata& metadata) { |
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auto* tracer = GetCallAttemptTracerFromContext(); |
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auto* call_tracker = |
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GetContext<LoadBalancingPolicy::SubchannelCallTrackerInterface*>(); |
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absl::Status status; |
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if (tracer != nullptr || |
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(call_tracker != nullptr && *call_tracker != nullptr)) { |
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grpc_status_code code = |
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metadata.get(GrpcStatusMetadata()).value_or(GRPC_STATUS_UNKNOWN); |
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if (code != GRPC_STATUS_OK) { |
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absl::string_view message; |
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if (const auto* grpc_message = |
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metadata.get_pointer(GrpcMessageMetadata())) { |
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message = grpc_message->as_string_view(); |
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} |
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status = absl::Status(static_cast<absl::StatusCode>(code), message); |
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} |
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} |
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if (tracer != nullptr) { |
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tracer->RecordReceivedTrailingMetadata( |
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status, &metadata, |
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&GetContext<CallContext>()->call_stats()->transport_stream_stats); |
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} |
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if (call_tracker != nullptr && *call_tracker != nullptr) { |
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LbMetadata lb_metadata(&metadata); |
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BackendMetricAccessor backend_metric_accessor(&metadata); |
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LoadBalancingPolicy::SubchannelCallTrackerInterface::FinishArgs args = { |
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peer_string_.as_string_view(), status, &lb_metadata, |
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&backend_metric_accessor}; |
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(*call_tracker)->Finish(args); |
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delete *call_tracker; |
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} |
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} |
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void LbCallTracingFilter::Call::OnFinalize(const grpc_call_final_info*) { |
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auto* tracer = GetCallAttemptTracerFromContext(); |
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if (tracer == nullptr) return; |
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gpr_timespec latency = |
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gpr_cycle_counter_sub(gpr_get_cycle_counter(), lb_call_start_time_); |
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tracer->RecordEnd(latency); |
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} |
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} // namespace grpc_core
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@ -0,0 +1,79 @@ |
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// Copyright 2024 gRPC authors.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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#ifndef GRPC_SRC_CORE_CLIENT_CHANNEL_LB_CALL_TRACING_FILTER_H |
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#define GRPC_SRC_CORE_CLIENT_CHANNEL_LB_CALL_TRACING_FILTER_H |
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namespace grpc_core { |
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// A filter to handle updating with the call tracer and LB subchannel
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// call tracker inside the LB call.
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// FIXME: register only when call v3 experiment is enabled
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class LbCallTracingFilter { |
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public: |
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static absl::StatusOr<LbCallTracingFilter> Create(const ChannelArgs&, |
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ChannelFilter::Args) { |
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return LbCallTracingFilter(); |
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} |
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class Call { |
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public: |
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void OnClientInitialMetadata(ClientMetadata& metadata); |
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void OnServerInitialMetadata(ServerMetadata& metadata); |
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static const NoInterceptor OnClientToServerMessage; |
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static const NoInterceptor OnServerToClientMessage; |
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void OnClientToServerHalfClose(); |
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void OnServerTrailingMetadata(ServerMetadata& metadata); |
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void OnFinalize(const grpc_call_final_info*); |
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private: |
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// Interface for accessing backend metric data in the LB call tracker.
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class BackendMetricAccessor |
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: public LoadBalancingPolicy::BackendMetricAccessor { |
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public: |
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explicit BackendMetricAccessor( |
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grpc_metadata_batch* server_trailing_metadata) |
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: server_trailing_metadata_(server_trailing_metadata) {} |
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~BackendMetricAccessor() override; |
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const BackendMetricData* GetBackendMetricData() override; |
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private: |
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class BackendMetricAllocator : public BackendMetricAllocatorInterface { |
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public: |
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BackendMetricData* AllocateBackendMetricData() override { |
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return GetContext<Arena>()->New<BackendMetricData>(); |
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} |
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char* AllocateString(size_t size) override { |
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return static_cast<char*>(GetContext<Arena>()->Alloc(size)); |
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} |
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}; |
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grpc_metadata_batch* server_trailing_metadata_; |
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const BackendMetricData* backend_metric_data_ = nullptr; |
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}; |
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// FIXME: this isn't the right place to measure this from -- should be
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// doing it from before we do the LB pick
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gpr_cycle_counter lb_call_start_time_ = gpr_get_cycle_counter(); |
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Slice peer_string_; |
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}; |
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}; |
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} // namespace grpc_core
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#endif |
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@ -0,0 +1,333 @@ |
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// Copyright 2024 gRPC authors.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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#include "src/core/client_channel/load_balanced_call_destination.h" |
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#include "src/core/client_channel/client_channel_internal.h" |
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#include "src/core/client_channel/subchannel.h" |
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#include "src/core/lib/channel/call_tracer.h" |
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#include "src/core/lib/channel/status_util.h" |
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namespace grpc_core { |
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// Defined in legacy client channel filter.
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// TODO(roth): Move these here when we remove the legacy filter.
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extern TraceFlag grpc_client_channel_trace; |
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extern TraceFlag grpc_client_channel_call_trace; |
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extern TraceFlag grpc_client_channel_lb_call_trace; |
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namespace { |
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class LbMetadata : public LoadBalancingPolicy::MetadataInterface { |
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public: |
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explicit LbMetadata(grpc_metadata_batch* batch) : batch_(batch) {} |
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void Add(absl::string_view key, absl::string_view value) override { |
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if (batch_ == nullptr) return; |
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// Gross, egregious hack to support legacy grpclb behavior.
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// TODO(ctiller): Use a promise context for this once that plumbing is done.
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if (key == GrpcLbClientStatsMetadata::key()) { |
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batch_->Set( |
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GrpcLbClientStatsMetadata(), |
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const_cast<GrpcLbClientStats*>( |
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reinterpret_cast<const GrpcLbClientStats*>(value.data()))); |
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return; |
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} |
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batch_->Append(key, Slice::FromStaticString(value), |
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[key](absl::string_view error, const Slice& value) { |
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gpr_log(GPR_ERROR, "%s", |
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absl::StrCat(error, " key:", key, |
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" value:", value.as_string_view()) |
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.c_str()); |
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}); |
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} |
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std::vector<std::pair<std::string, std::string>> TestOnlyCopyToVector() |
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override { |
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if (batch_ == nullptr) return {}; |
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Encoder encoder; |
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batch_->Encode(&encoder); |
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return encoder.Take(); |
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} |
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absl::optional<absl::string_view> Lookup(absl::string_view key, |
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std::string* buffer) const override { |
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if (batch_ == nullptr) return absl::nullopt; |
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return batch_->GetStringValue(key, buffer); |
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} |
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private: |
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class Encoder { |
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public: |
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void Encode(const Slice& key, const Slice& value) { |
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out_.emplace_back(std::string(key.as_string_view()), |
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std::string(value.as_string_view())); |
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} |
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template <class Which> |
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void Encode(Which, const typename Which::ValueType& value) { |
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auto value_slice = Which::Encode(value); |
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out_.emplace_back(std::string(Which::key()), |
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std::string(value_slice.as_string_view())); |
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} |
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void Encode(GrpcTimeoutMetadata, |
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const typename GrpcTimeoutMetadata::ValueType&) {} |
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void Encode(HttpPathMetadata, const Slice&) {} |
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void Encode(HttpMethodMetadata, |
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const typename HttpMethodMetadata::ValueType&) {} |
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std::vector<std::pair<std::string, std::string>> Take() { |
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return std::move(out_); |
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} |
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private: |
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std::vector<std::pair<std::string, std::string>> out_; |
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}; |
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grpc_metadata_batch* batch_; |
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}; |
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void MaybeCreateCallAttemptTracer(bool is_transparent_retry) { |
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auto* call_tracer = GetContext<ClientCallTracer>(); |
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if (call_tracer == nullptr) return; |
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auto* tracer = call_tracer->StartNewAttempt(is_transparent_retry); |
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SetContext<CallTracerInterface>(tracer); |
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} |
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class LbCallState : public ClientChannelLbCallState { |
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public: |
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void* Alloc(size_t size) override { return GetContext<Arena>()->Alloc(size); } |
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// Internal API to allow first-party LB policies to access per-call
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// attributes set by the ConfigSelector.
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ServiceConfigCallData::CallAttributeInterface* GetCallAttribute( |
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UniqueTypeName type) const override { |
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auto* service_config_call_data = GetContext<ServiceConfigCallData>(); |
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return service_config_call_data->GetCallAttribute(type); |
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} |
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ClientCallTracer::CallAttemptTracer* GetCallAttemptTracer() const override { |
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auto* legacy_context = GetContext<grpc_call_context_element>(); |
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return static_cast<ClientCallTracer::CallAttemptTracer*>( |
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legacy_context[GRPC_CONTEXT_CALL_TRACER].value); |
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} |
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}; |
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// TODO(roth): Remove this in favor of the gprpp Match() function once
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// we can do that without breaking lock annotations.
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template <typename T> |
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T HandlePickResult( |
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LoadBalancingPolicy::PickResult* result, |
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std::function<T(LoadBalancingPolicy::PickResult::Complete*)> complete_func, |
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std::function<T(LoadBalancingPolicy::PickResult::Queue*)> queue_func, |
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std::function<T(LoadBalancingPolicy::PickResult::Fail*)> fail_func, |
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std::function<T(LoadBalancingPolicy::PickResult::Drop*)> drop_func) { |
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auto* complete_pick = |
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absl::get_if<LoadBalancingPolicy::PickResult::Complete>(&result->result); |
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if (complete_pick != nullptr) { |
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return complete_func(complete_pick); |
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} |
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auto* queue_pick = |
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absl::get_if<LoadBalancingPolicy::PickResult::Queue>(&result->result); |
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if (queue_pick != nullptr) { |
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return queue_func(queue_pick); |
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} |
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auto* fail_pick = |
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absl::get_if<LoadBalancingPolicy::PickResult::Fail>(&result->result); |
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if (fail_pick != nullptr) { |
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return fail_func(fail_pick); |
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} |
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auto* drop_pick = |
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absl::get_if<LoadBalancingPolicy::PickResult::Drop>(&result->result); |
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GPR_ASSERT(drop_pick != nullptr); |
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return drop_func(drop_pick); |
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} |
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// Does an LB pick for a call. Returns one of the following things:
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// - Continue{}, meaning to queue the pick
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// - a non-OK status, meaning to fail the call
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// - a connected subchannel, meaning that the pick is complete
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// When the pick is complete, pushes client_initial_metadata onto
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// call_initiator. Also adds the subchannel call tracker (if any) to
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// context.
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LoopCtl<absl::StatusOr<RefCountedPtr<ConnectedSubchannel>>> PickSubchannel( |
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LoadBalancingPolicy::SubchannelPicker& picker, |
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UnstartedCallHandler& unstarted_handler) { |
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// Perform LB pick.
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auto& client_initial_metadata = |
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unstarted_handler.UnprocessedClientInitialMetadata(); |
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LoadBalancingPolicy::PickArgs pick_args; |
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Slice* path = client_initial_metadata.get_pointer(HttpPathMetadata()); |
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GPR_ASSERT(path != nullptr); |
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pick_args.path = path->as_string_view(); |
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LbCallState lb_call_state; |
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pick_args.call_state = &lb_call_state; |
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LbMetadata initial_metadata(&client_initial_metadata); |
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pick_args.initial_metadata = &initial_metadata; |
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auto result = picker.Pick(pick_args); |
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// Handle result.
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return HandlePickResult< |
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LoopCtl<absl::StatusOr<RefCountedPtr<ConnectedSubchannel>>>>( |
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&result, |
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// CompletePick
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[&](LoadBalancingPolicy::PickResult::Complete* complete_pick) |
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-> LoopCtl<absl::StatusOr<RefCountedPtr<ConnectedSubchannel>>> { |
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if (GRPC_TRACE_FLAG_ENABLED(grpc_client_channel_lb_call_trace)) { |
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gpr_log(GPR_INFO, |
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"client_channel: %sLB pick succeeded: subchannel=%p", |
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GetContext<Activity>()->DebugTag().c_str(), |
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complete_pick->subchannel.get()); |
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} |
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GPR_ASSERT(complete_pick->subchannel != nullptr); |
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// Grab a ref to the connected subchannel while we're still
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// holding the data plane mutex.
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auto* subchannel = DownCast<ClientChannel::SubchannelWrapper*>( |
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complete_pick->subchannel.get()); |
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auto connected_subchannel = subchannel->connected_subchannel(); |
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// If the subchannel has no connected subchannel (e.g., if the
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// subchannel has moved out of state READY but the LB policy hasn't
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// yet seen that change and given us a new picker), then just
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// queue the pick. We'll try again as soon as we get a new picker.
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if (connected_subchannel == nullptr) { |
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if (GRPC_TRACE_FLAG_ENABLED(grpc_client_channel_lb_call_trace)) { |
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gpr_log(GPR_INFO, |
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"client_channel: %ssubchannel returned by LB picker " |
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"has no connected subchannel; queueing pick", |
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GetContext<Activity>()->DebugTag().c_str()); |
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} |
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return Continue{}; |
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} |
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// If the LB policy returned a call tracker, inform it that the
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// call is starting and add it to context, so that we can notify
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// it when the call finishes.
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if (complete_pick->subchannel_call_tracker != nullptr) { |
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complete_pick->subchannel_call_tracker->Start(); |
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SetContext(complete_pick->subchannel_call_tracker.release()); |
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} |
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// Return the connected subchannel.
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return connected_subchannel; |
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}, |
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// QueuePick
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[&](LoadBalancingPolicy::PickResult::Queue* /*queue_pick*/) { |
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if (GRPC_TRACE_FLAG_ENABLED(grpc_client_channel_lb_call_trace)) { |
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gpr_log(GPR_INFO, "client_channel: %sLB pick queued", |
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GetContext<Activity>()->DebugTag().c_str()); |
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} |
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return Continue{}; |
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}, |
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// FailPick
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[&](LoadBalancingPolicy::PickResult::Fail* fail_pick) |
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-> LoopCtl<absl::StatusOr<RefCountedPtr<ConnectedSubchannel>>> { |
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if (GRPC_TRACE_FLAG_ENABLED(grpc_client_channel_lb_call_trace)) { |
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gpr_log(GPR_INFO, "client_channel: %sLB pick failed: %s", |
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GetContext<Activity>()->DebugTag().c_str(), |
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fail_pick->status.ToString().c_str()); |
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} |
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// If wait_for_ready is false, then the error indicates the RPC
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// attempt's final status.
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if (!unstarted_handler.UnprocessedClientInitialMetadata() |
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.GetOrCreatePointer(WaitForReady()) |
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->value) { |
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return MaybeRewriteIllegalStatusCode(std::move(fail_pick->status), |
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"LB pick"); |
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} |
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// If wait_for_ready is true, then queue to retry when we get a new
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// picker.
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return Continue{}; |
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}, |
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// DropPick
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[&](LoadBalancingPolicy::PickResult::Drop* drop_pick) |
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-> LoopCtl<absl::StatusOr<RefCountedPtr<ConnectedSubchannel>>> { |
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if (GRPC_TRACE_FLAG_ENABLED(grpc_client_channel_lb_call_trace)) { |
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gpr_log(GPR_INFO, "client_channel: %sLB pick dropped: %s", |
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GetContext<Activity>()->DebugTag().c_str(), |
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drop_pick->status.ToString().c_str()); |
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} |
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return grpc_error_set_int(MaybeRewriteIllegalStatusCode( |
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std::move(drop_pick->status), "LB drop"), |
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StatusIntProperty::kLbPolicyDrop, 1); |
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}); |
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} |
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} // namespace
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void LoadBalancedCallDestination::StartCall( |
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UnstartedCallHandler unstarted_handler) { |
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// If there is a call tracer, create a call attempt tracer.
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bool* is_transparent_retry_metadata = |
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unstarted_handler.UnprocessedClientInitialMetadata().get_pointer( |
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IsTransparentRetry()); |
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bool is_transparent_retry = is_transparent_retry_metadata != nullptr |
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? *is_transparent_retry_metadata |
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: false; |
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MaybeCreateCallAttemptTracer(is_transparent_retry); |
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// Spawn a promise to do the LB pick.
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// This will eventually start the call.
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unstarted_handler.SpawnGuarded("lb_pick", [was_queued = true, |
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unstarted_handler = |
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std::move(unstarted_handler), |
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picker = picker_]() mutable { |
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return Map( |
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// Wait for the LB picker.
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Loop([last_picker = |
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RefCountedPtr<LoadBalancingPolicy::SubchannelPicker>(), |
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unstarted_handler, &was_queued, picker]() mutable { |
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return Map(picker.Next(last_picker), |
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[unstarted_handler, &last_picker, &was_queued]( |
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RefCountedPtr<LoadBalancingPolicy::SubchannelPicker> |
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picker) mutable { |
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last_picker = std::move(picker); |
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// Returns 3 possible things:
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// - Continue to queue the pick
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// - non-OK status to fail the pick
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// - a connected subchannel to complete the pick
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auto result = |
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PickSubchannel(*last_picker, unstarted_handler); |
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if (absl::holds_alternative<Continue>(result)) { |
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was_queued = true; |
||||
} |
||||
return result; |
||||
}); |
||||
}), |
||||
// Create call stack on the connected subchannel.
|
||||
[unstarted_handler = std::move(unstarted_handler), |
||||
&was_queued](absl::StatusOr<RefCountedPtr<ConnectedSubchannel>> |
||||
connected_subchannel) { |
||||
if (!connected_subchannel.ok()) { |
||||
return connected_subchannel.status(); |
||||
} |
||||
// LB pick is done, so indicate that we've committed.
|
||||
auto* on_commit = GetContext<LbOnCommit>(); |
||||
if (on_commit != nullptr && *on_commit != nullptr) { |
||||
(*on_commit)(); |
||||
} |
||||
// If it was queued, add a trace annotation.
|
||||
if (was_queued) { |
||||
auto* tracer = |
||||
MaybeGetContext<ClientCallTracer::CallAttemptTracer>(); |
||||
if (tracer != nullptr) { |
||||
tracer->RecordAnnotation("Delayed LB pick complete."); |
||||
} |
||||
} |
||||
// Delegate to connected subchannel.
|
||||
// FIXME: need to insert LbCallTracingFilter at the top of the
|
||||
// stack
|
||||
(*connected_subchannel)->StartCall(std::move(unstarted_handler)); |
||||
return absl::OkStatus(); |
||||
}); |
||||
}); |
||||
} |
||||
|
||||
} // namespace grpc_core
|
||||
@ -0,0 +1,49 @@ |
||||
// Copyright 2024 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.
|
||||
|
||||
#ifndef GRPC_SRC_CORE_CLIENT_CHANNEL_LOAD_BALANCED_CALL_DESTINATION_H |
||||
#define GRPC_SRC_CORE_CLIENT_CHANNEL_LOAD_BALANCED_CALL_DESTINATION_H |
||||
|
||||
#include "absl/functional/any_invocable.h" |
||||
|
||||
#include "src/core/lib/promise/context.h" |
||||
#include "src/core/lib/transport/call_destination.h" |
||||
#include "src/core/load_balancing/lb_policy.h" |
||||
#include "src/core/client_channel/client_channel.h" |
||||
|
||||
namespace grpc_core { |
||||
|
||||
// Context type for LB on_commit callback.
|
||||
// TODO(ctiller): make this a struct, so we don't accidentally alias context
|
||||
// types
|
||||
using LbOnCommit = absl::AnyInvocable<void()>; |
||||
template <> |
||||
struct ContextType<LbOnCommit> {}; |
||||
|
||||
class LoadBalancedCallDestination final : public UnstartedCallDestination { |
||||
public: |
||||
explicit LoadBalancedCallDestination(ClientChannel::PickerObservable picker) |
||||
: picker_(std::move(picker)) {} |
||||
|
||||
void Orphaned() override {} |
||||
|
||||
void StartCall(UnstartedCallHandler unstarted_handler) override; |
||||
|
||||
private: |
||||
ClientChannel::PickerObservable picker_; |
||||
}; |
||||
|
||||
} // namespace grpc_core
|
||||
|
||||
#endif |
||||
Loading…
Reference in new issue