In RpcEvent use std::weak_ptr<Rpc> rather than Rpc* (#757)

[RFC=0002](https://github.com/googlecartographer/rfcs/blob/master/text/0002-cloud-based-mapping-1.md)
master
Christoph Schütte 2017-12-14 16:30:01 +01:00 committed by Wally B. Feed
parent 29e4395a5a
commit e023ec5ecc
4 changed files with 53 additions and 27 deletions

View File

@ -43,12 +43,14 @@ void SendUnaryFinish(ReaderWriter* reader_writer, ::grpc::Status status,
Rpc::Rpc(int method_index,
::grpc::ServerCompletionQueue* server_completion_queue,
ExecutionContext* execution_context,
const RpcHandlerInfo& rpc_handler_info, Service* service)
const RpcHandlerInfo& rpc_handler_info, Service* service,
WeakPtrFactory weak_ptr_factory)
: method_index_(method_index),
server_completion_queue_(server_completion_queue),
execution_context_(execution_context),
rpc_handler_info_(rpc_handler_info),
service_(service),
weak_ptr_factory_(weak_ptr_factory),
handler_(rpc_handler_info_.rpc_handler_factory(this, execution_context)) {
InitializeReadersAndWriters(rpc_handler_info_.rpc_type);
@ -64,7 +66,7 @@ Rpc::Rpc(int method_index,
std::unique_ptr<Rpc> Rpc::Clone() {
return cartographer::common::make_unique<Rpc>(
method_index_, server_completion_queue_, execution_context_,
rpc_handler_info_, service_);
rpc_handler_info_, service_, weak_ptr_factory_);
}
void Rpc::OnRequest() { handler_->OnRequestInternal(request_.get()); }
@ -74,7 +76,8 @@ void Rpc::OnReadsDone() { handler_->OnReadsDone(); }
void Rpc::RequestNextMethodInvocation() {
// Ask gRPC to notify us when the connection terminates.
SetRpcEventState(Event::DONE, true);
server_context_.AsyncNotifyWhenDone(new RpcEvent{Event::DONE, this});
server_context_.AsyncNotifyWhenDone(
new RpcEvent{Event::DONE, weak_ptr_factory_(this)});
// Make sure after terminating the connection, gRPC notifies us with this
// event.
@ -84,19 +87,20 @@ void Rpc::RequestNextMethodInvocation() {
service_->RequestAsyncBidiStreaming(
method_index_, &server_context_, streaming_interface(),
server_completion_queue_, server_completion_queue_,
new RpcEvent{Event::NEW_CONNECTION, this});
new RpcEvent{Event::NEW_CONNECTION, weak_ptr_factory_(this)});
break;
case ::grpc::internal::RpcMethod::CLIENT_STREAMING:
service_->RequestAsyncClientStreaming(
method_index_, &server_context_, streaming_interface(),
server_completion_queue_, server_completion_queue_,
new RpcEvent{Event::NEW_CONNECTION, this});
new RpcEvent{Event::NEW_CONNECTION, weak_ptr_factory_(this)});
break;
case ::grpc::internal::RpcMethod::NORMAL_RPC:
service_->RequestAsyncUnary(
method_index_, &server_context_, request_.get(),
streaming_interface(), server_completion_queue_,
server_completion_queue_, new RpcEvent{Event::NEW_CONNECTION, this});
server_completion_queue_,
new RpcEvent{Event::NEW_CONNECTION, weak_ptr_factory_(this)});
break;
default:
LOG(FATAL) << "RPC type not implemented.";
@ -109,8 +113,8 @@ void Rpc::RequestStreamingReadIfNeeded() {
case ::grpc::internal::RpcMethod::BIDI_STREAMING:
case ::grpc::internal::RpcMethod::CLIENT_STREAMING:
SetRpcEventState(Event::READ, true);
async_reader_interface()->Read(request_.get(),
new RpcEvent{Event::READ, this});
async_reader_interface()->Read(
request_.get(), new RpcEvent{Event::READ, weak_ptr_factory_(this)});
break;
case ::grpc::internal::RpcMethod::NORMAL_RPC:
// For NORMAL_RPC we don't have to do anything here, since gRPC
@ -149,18 +153,19 @@ void Rpc::SendFinish(std::unique_ptr<::google::protobuf::Message> message,
switch (rpc_handler_info_.rpc_type) {
case ::grpc::internal::RpcMethod::BIDI_STREAMING:
CHECK(!message);
server_async_reader_writer_->Finish(status,
new RpcEvent{Event::FINISH, this});
server_async_reader_writer_->Finish(
status, new RpcEvent{Event::FINISH, weak_ptr_factory_(this)});
break;
case ::grpc::internal::RpcMethod::CLIENT_STREAMING:
response_ = std::move(message);
SendUnaryFinish(server_async_reader_.get(), status, response_.get(),
new RpcEvent{Event::FINISH, this});
new RpcEvent{Event::FINISH, weak_ptr_factory_(this)});
break;
case ::grpc::internal::RpcMethod::NORMAL_RPC:
response_ = std::move(message);
SendUnaryFinish(server_async_response_writer_.get(), status,
response_.get(), new RpcEvent{Event::FINISH, this});
response_.get(),
new RpcEvent{Event::FINISH, weak_ptr_factory_(this)});
break;
default:
LOG(FATAL) << "RPC type not implemented.";
@ -198,8 +203,8 @@ void Rpc::PerformWriteIfNeeded() {
if (response_) {
SetRpcEventState(Event::WRITE, true);
async_writer_interface()->Write(*response_.get(),
new RpcEvent{Event::WRITE, this});
async_writer_interface()->Write(
*response_.get(), new RpcEvent{Event::WRITE, weak_ptr_factory_(this)});
} else {
CHECK(send_queue_.empty());
SendFinish(nullptr /* message */, send_item.status);
@ -314,23 +319,34 @@ ActiveRpcs::~ActiveRpcs() {
}
}
Rpc* ActiveRpcs::Add(std::unique_ptr<Rpc> rpc) {
std::shared_ptr<Rpc> ActiveRpcs::Add(std::unique_ptr<Rpc> rpc) {
cartographer::common::MutexLocker locker(&lock_);
const auto result = rpcs_.emplace(rpc.release());
std::shared_ptr<Rpc> shared_ptr_rpc = std::move(rpc);
const auto result = rpcs_.emplace(shared_ptr_rpc.get(), shared_ptr_rpc);
CHECK(result.second) << "RPC already active.";
return *result.first;
return shared_ptr_rpc;
}
bool ActiveRpcs::Remove(Rpc* rpc) {
cartographer::common::MutexLocker locker(&lock_);
auto it = rpcs_.find(rpc);
if (it != rpcs_.end()) {
delete rpc;
rpcs_.erase(it);
return true;
}
return false;
}
Rpc::WeakPtrFactory ActiveRpcs::GetWeakPtrFactory() {
return [this](Rpc* rpc) { return GetWeakPtr(rpc); };
}
std::weak_ptr<Rpc> ActiveRpcs::GetWeakPtr(Rpc* rpc) {
cartographer::common::MutexLocker locker(&lock_);
auto it = rpcs_.find(rpc);
CHECK(it != rpcs_.end());
return it->second;
}
} // namespace framework
} // namespace cartographer_grpc

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@ -37,15 +37,17 @@ namespace framework {
class Service;
class Rpc {
public:
using WeakPtrFactory = std::function<std::weak_ptr<Rpc>(Rpc*)>;
enum class Event { NEW_CONNECTION = 0, READ, WRITE, FINISH, DONE };
struct RpcEvent {
const Event event;
Rpc* rpc;
std::weak_ptr<Rpc> rpc;
};
Rpc(int method_index, ::grpc::ServerCompletionQueue* server_completion_queue,
ExecutionContext* execution_context,
const RpcHandlerInfo& rpc_handler_info, Service* service);
const RpcHandlerInfo& rpc_handler_info, Service* service,
WeakPtrFactory weak_ptr_factory);
std::unique_ptr<Rpc> Clone();
void OnRequest();
void OnReadsDone();
@ -85,6 +87,7 @@ class Rpc {
ExecutionContext* execution_context_;
RpcHandlerInfo rpc_handler_info_;
Service* service_;
WeakPtrFactory weak_ptr_factory_;
::grpc::ServerContext server_context_;
// These state variables indicate whether the corresponding event is currently
@ -122,12 +125,15 @@ class ActiveRpcs {
ActiveRpcs();
~ActiveRpcs() EXCLUDES(lock_);
Rpc* Add(std::unique_ptr<Rpc> rpc) EXCLUDES(lock_);
std::shared_ptr<Rpc> Add(std::unique_ptr<Rpc> rpc) EXCLUDES(lock_);
bool Remove(Rpc* rpc) EXCLUDES(lock_);
Rpc::WeakPtrFactory GetWeakPtrFactory();
private:
std::weak_ptr<Rpc> GetWeakPtr(Rpc* rpc);
cartographer::common::Mutex lock_;
std::unordered_set<Rpc*> rpcs_;
std::map<Rpc*, std::shared_ptr<Rpc>> rpcs_;
};
} // namespace framework

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@ -66,8 +66,11 @@ void Server::RunCompletionQueue(
void* tag;
while (completion_queue->Next(&tag, &ok)) {
auto* rpc_event = static_cast<Rpc::RpcEvent*>(tag);
rpc_event->rpc->service()->HandleEvent(rpc_event->event, rpc_event->rpc,
ok);
if (auto rpc = rpc_event->rpc.lock()) {
rpc->service()->HandleEvent(rpc_event->event, rpc.get(), ok);
} else {
LOG(WARNING) << "Ignoring stale event.";
}
delete rpc_event;
}
}

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@ -40,9 +40,10 @@ void Service::StartServing(
int i = 0;
for (const auto& rpc_handler_info : rpc_handler_infos_) {
for (auto& completion_queue_thread : completion_queue_threads) {
Rpc* rpc = active_rpcs_.Add(cartographer::common::make_unique<Rpc>(
std::shared_ptr<Rpc> rpc =
active_rpcs_.Add(cartographer::common::make_unique<Rpc>(
i, completion_queue_thread.completion_queue(), execution_context,
rpc_handler_info.second, this));
rpc_handler_info.second, this, active_rpcs_.GetWeakPtrFactory()));
rpc->RequestNextMethodInvocation();
}
++i;