Merge pull request #1122 from majestrate/ntcp-threadpool

NTCP threadpool

libi2pd/Config.cpp

@@ -73,6 +73,7 @@ namespace config {
 			("limits.transittunnels", value<uint16_t>()->default_value(2500), "Maximum active transit sessions (default:2500)")
 			("limits.ntcpsoft", value<uint16_t>()->default_value(0),          "Threshold to start probabalistic backoff with ntcp sessions (default: use system limit)")
 			("limits.ntcphard", value<uint16_t>()->default_value(0),          "Maximum number of ntcp sessions (default: use system limit)")
+			("limits.ntcpthreads", value<uint16_t>()->default_value(1),       "Maximum number of threads used by NTCP DH worker (default: 1)")
 		;
 
 		options_description httpserver("HTTP Server options");

libi2pd/CryptoWorker.h

@@ -0,0 +1,81 @@
+#ifndef CRYPTO_WORKER_H_
+#define CRYPTO_WORKER_H_
+
+#include <condition_variable>
+#include <mutex>
+#include <deque>
+#include <thread>
+#include <vector>
+#include <memory>
+
+namespace i2p
+{
+namespace worker
+{
+	template<typename Caller>
+	struct ThreadPool
+	{
+		typedef std::function<void(void)> ResultFunc;
+		typedef std::function<ResultFunc(void)> WorkFunc;
+		typedef std::pair<std::shared_ptr<Caller>, WorkFunc> Job;
+		typedef std::mutex mtx_t;
+		typedef std::unique_lock<mtx_t> lock_t;
+		typedef std::condition_variable cond_t;
+		ThreadPool(int workers)
+		{
+			stop = false;
+			if(workers > 0)
+			{
+				while(workers--)
+				{
+					threads.emplace_back([this] {
+							for (;;)
+							{
+								Job job;
+								{
+									lock_t lock(this->queue_mutex);
+									this->condition.wait(
+										lock, [this] { return this->stop || !this->jobs.empty(); });
+									if (this->stop && this->jobs.empty()) return;
+									job = std::move(this->jobs.front());
+									this->jobs.pop_front();
+								}
+								ResultFunc result = job.second();
+								job.first->GetService().post(result);
+							}
+					});
+				}
+			}
+		};
+
+		void Offer(const Job & job)
+		{
+			{
+				lock_t lock(queue_mutex);
+				if (stop) return;
+				jobs.emplace_back(job);
+			}
+			condition.notify_one();
+		}
+
+		~ThreadPool()
+		{
+			{
+				lock_t lock(queue_mutex);
+				stop = true;
+			}
+			condition.notify_all();
+			for(auto &t: threads) t.join();
+		}
+
+		std::vector<std::thread> threads;
+		std::deque<Job> jobs;
+		mtx_t queue_mutex;
+		cond_t condition;
+		bool stop;
+	};
+}
+}
+
+
+#endif

libi2pd/NTCPSession.cpp

@@ -105,6 +105,11 @@ namespace transport
 		transports.PeerConnected (shared_from_this ());
 	}
 
+	boost::asio::io_service & NTCPSession::GetService()
+	{
+		return m_Server.GetService();
+	}
+
 	void NTCPSession::ClientLogin ()
 	{
 		if (!m_DHKeysPair)
@@ -171,27 +176,14 @@ namespace transport
 					return;
 				}
 			}
-#if ((__GNUC__ == 4) && (__GNUC_MINOR__ <= 7)) || defined(__NetBSD__)
-// due the bug in gcc 4.7. std::shared_future.get() is not const
-			if (!m_DHKeysPair)
-				m_DHKeysPair = transports.GetNextDHKeysPair ();
-			CreateAESKey (m_Establisher->phase1.pubKey);
-			SendPhase2 ();
-#else
 			// TODO: check for number of pending keys
 			auto s = shared_from_this ();
-			auto keyCreated = std::async (std::launch::async, [s] ()
-				{
+			m_Server.Work(s, [s]() -> std::function<void(void)> {
 					if (!s->m_DHKeysPair)
 						s->m_DHKeysPair = transports.GetNextDHKeysPair ();
 					s->CreateAESKey (s->m_Establisher->phase1.pubKey);
-				}).share ();
-			m_Server.GetService ().post ([s, keyCreated]()
-			{
-				keyCreated.get ();
-				s->SendPhase2 ();
+					return std::bind(&NTCPSession::SendPhase2, s);
 			});
-#endif
 		}
 	}
 
@@ -213,7 +205,6 @@ namespace transport
 		m_Encryption.Encrypt ((uint8_t *)&m_Establisher->phase2.encrypted, sizeof(m_Establisher->phase2.encrypted), (uint8_t *)&m_Establisher->phase2.encrypted);
 		boost::asio::async_write(m_Socket, boost::asio::buffer (&m_Establisher->phase2, sizeof (NTCPPhase2)), boost::asio::transfer_all(),
 			std::bind(&NTCPSession::HandlePhase2Sent, shared_from_this(), std::placeholders::_1, std::placeholders::_2, tsB));
-
 	}
 
 	void NTCPSession::HandlePhase2Sent (const boost::system::error_code& ecode, std::size_t bytes_transferred, uint32_t tsB)
@@ -250,24 +241,11 @@ namespace transport
 		}
 		else
 		{
-#if ((__GNUC__ == 4) && (__GNUC_MINOR__ <= 7)) || defined(__NetBSD__)
-// due the bug in gcc 4.7. std::shared_future.get() is not const
-			CreateAESKey (m_Establisher->phase2.pubKey);
-			HandlePhase2 ();
-#else
 			auto s = shared_from_this ();
-			// create AES key in separate thread
-			auto keyCreated = std::async (std::launch::async, [s] ()
-				{
+			m_Server.Work(s, [s]() -> std::function<void(void)> {
 				s->CreateAESKey (s->m_Establisher->phase2.pubKey);
-				}).share (); // TODO: use move capture in C++ 14 instead shared_future
-			// let other operations execute while a key gets created
-			m_Server.GetService ().post ([s, keyCreated]()
-				{
-					keyCreated.get (); // we might wait if no more pending operations
-					s->HandlePhase2 ();
+				return std::bind(&NTCPSession::HandlePhase2, s);
 			});
-#endif
 		}
 	}
 
@@ -788,12 +766,14 @@ namespace transport
 	}
 
 //-----------------------------------------
-	NTCPServer::NTCPServer ():
+	NTCPServer::NTCPServer (int workers):
 		m_IsRunning (false), m_Thread (nullptr), m_Work (m_Service),
 		m_TerminationTimer (m_Service), m_NTCPAcceptor (nullptr), m_NTCPV6Acceptor (nullptr),
 		m_ProxyType(eNoProxy), m_Resolver(m_Service), m_ProxyEndpoint(nullptr),
 		m_SoftLimit(0), m_HardLimit(0)
 	{
+		if(workers <= 0) workers = 1;
+		m_CryptoPool = std::make_shared<Pool>(workers);
 	}
 
 	NTCPServer::~NTCPServer ()

libi2pd/NTCPSession.h

@@ -12,6 +12,7 @@
 #include "RouterInfo.h"
 #include "I2NPProtocol.h"
 #include "TransportSession.h"
+#include "CryptoWorker.h"
 
 namespace i2p
 {
@@ -55,6 +56,7 @@ namespace transport
 			void Done ();
 
 			boost::asio::ip::tcp::socket& GetSocket () { return m_Socket; };
+			boost::asio::io_service & GetService();
 			bool IsEstablished () const { return m_IsEstablished; };
 			bool IsTerminated () const { return m_IsTerminated; };
 
@@ -131,6 +133,8 @@ namespace transport
 	{
 		public:
 
+			typedef i2p::worker::ThreadPool<NTCPSession> Pool;
+
 			enum RemoteAddressType
 			{
 				eIP4Address,
@@ -146,7 +150,7 @@ namespace transport
 			};
 
 
-			NTCPServer ();
+			NTCPServer (int workers=4);
 			~NTCPServer ();
 
 			void Start ();
@@ -169,6 +173,10 @@ namespace transport
 
 			void SetSessionLimits(uint16_t softLimit, uint16_t hardLimit) { m_SoftLimit = softLimit; m_HardLimit = hardLimit; }
 			bool ShouldLimit() const { return ShouldHardLimit() || ShouldSoftLimit(); }
+			void Work(std::shared_ptr<NTCPSession> conn, Pool::WorkFunc work)
+			{
+				m_CryptoPool->Offer({conn, work});
+			}
 		private:
 
 			/** @brief return true for hard limit */
@@ -210,6 +218,8 @@ namespace transport
 			boost::asio::ip::tcp::resolver m_Resolver;
 			boost::asio::ip::tcp::endpoint * m_ProxyEndpoint;
 
+			std::shared_ptr<Pool> m_CryptoPool;
+
 			uint16_t m_SoftLimit, m_HardLimit;
 		public:
 

libi2pd/Transports.cpp

@@ -153,9 +153,10 @@ namespace transport
 		m_Thread = new std::thread (std::bind (&Transports::Run, this));
 		std::string ntcpproxy; i2p::config::GetOption("ntcpproxy", ntcpproxy);
 		i2p::http::URL proxyurl;
-		uint16_t softLimit, hardLimit;
+		uint16_t softLimit, hardLimit, threads;
 		i2p::config::GetOption("limits.ntcpsoft", softLimit);
 		i2p::config::GetOption("limits.ntcphard", hardLimit);
+		i2p::config::GetOption("limits.ntcpthreads", threads);
 		if(softLimit > 0 && hardLimit > 0 && softLimit >= hardLimit)
 		{
 			LogPrint(eLogError, "ntcp soft limit must be less than ntcp hard limit");
@@ -167,7 +168,7 @@ namespace transport
 			{
 				if(proxyurl.schema == "socks" || proxyurl.schema == "http")
 				{
-					m_NTCPServer = new NTCPServer();
+					m_NTCPServer = new NTCPServer(threads);
 					m_NTCPServer->SetSessionLimits(softLimit, hardLimit);
 					NTCPServer::ProxyType proxytype = NTCPServer::eSocksProxy;
 
@@ -198,7 +199,7 @@ namespace transport
 			if (!address) continue;
 			if (m_NTCPServer == nullptr && enableNTCP)
 			{
-				m_NTCPServer = new NTCPServer ();
+				m_NTCPServer = new NTCPServer (threads);
 				m_NTCPServer->SetSessionLimits(softLimit, hardLimit);
 				m_NTCPServer->Start ();
 				if (!(m_NTCPServer->IsBoundV6() || m_NTCPServer->IsBoundV4())) {