refactored socket reading code to not use async. operations unnecessarily

ChangeLog

@@ -33,6 +33,8 @@
 	  incoming connection
 	* added more detailed instrumentation of the disk I/O thread
 
+	* refactored socket reading code to not use async. operations unnecessarily
+	* some timer optimizations
 	* removed the reuse-address flag on the listen socket
 	* fixed bug where local peer discovery and DHT wouldn't be announced to without trackers
 	* fixed bug in bdecoder when decoding invalid messages

include/libtorrent/natpmp.hpp

@@ -79,7 +79,7 @@ private:
 	void on_reply(error_code const& e
 		, std::size_t bytes_transferred);
 	void try_next_mapping(int i, mutex::scoped_lock& l);
-	void update_expiration_timer();
+	void update_expiration_timer(mutex::scoped_lock& l);
 	void mapping_expired(error_code const& e, int i);
 	void close_impl(mutex::scoped_lock& l);
 

include/libtorrent/peer_connection.hpp

@@ -560,6 +560,9 @@ namespace libtorrent
 
 	protected:
 
+		enum sync_t { read_async, read_sync };
+		size_t try_read(sync_t s, error_code& ec);
+
 		virtual void get_specific_peer_info(peer_info& p) const = 0;
 
 		virtual void write_choke() = 0;
@@ -637,6 +640,8 @@ namespace libtorrent
 			, std::size_t bytes_transferred);
 		void on_receive_data(error_code const& error
 			, std::size_t bytes_transferred);
+		void on_receive_data_nolock(error_code const& error
+			, std::size_t bytes_transferred);
 
 		// this is the limit on the number of outstanding requests
 		// we have to this peer. This is initialized to the settings

src/connection_queue.cpp

@@ -165,6 +165,7 @@ namespace libtorrent
 			i != m_queue.end(); ++i)
 		{
 			if (i->connecting) ++num_connecting;
+			else TORRENT_ASSERT(i->expires == max_time());
 		}
 		TORRENT_ASSERT(num_connecting == m_num_connecting);
 	}
@@ -198,7 +199,7 @@ namespace libtorrent
 		while (i != m_queue.end())
 		{
 			TORRENT_ASSERT(i->connecting == false);
-			ptime expire = time_now() + i->timeout;
+			ptime expire = time_now_hires() + i->timeout;
 			if (m_num_connecting == 0)
 			{
 				error_code ec;
@@ -262,7 +263,7 @@ namespace libtorrent
 		if (e) return;
 
 		ptime next_expire = max_time();
-		ptime now = time_now();
+		ptime now = time_now_hires() + milliseconds(100);
 		std::list<entry> timed_out;
 		for (std::list<entry>::iterator i = m_queue.begin();
 			!m_queue.empty() && i != m_queue.end();)

src/natpmp.cpp

@@ -477,15 +477,15 @@ void natpmp::on_reply(error_code const& e
 	m_currently_mapping = -1;
 	m->action = mapping_t::action_none;
 	m_send_timer.cancel(ec);
-	update_expiration_timer();
+	update_expiration_timer(l);
 	try_next_mapping(index, l);
 }
 
-void natpmp::update_expiration_timer()
+void natpmp::update_expiration_timer(mutex::scoped_lock& l)
 {
 	if (m_abort) return;
 
-	ptime now = time_now();
+	ptime now = time_now() + milliseconds(100);
 /*
 #if defined(TORRENT_LOGGING) || defined(TORRENT_VERBOSE_LOGGING)
 	m_log << time_now_string() << "update_expiration_timer " << std::endl;
@@ -509,10 +509,20 @@ void natpmp::update_expiration_timer()
 	{
 		if (i->protocol == none
 			|| i->action != mapping_t::action_none) continue;
-		if (i->expires < min_expire)
+		int index = i - m_mappings.begin();
+		if (i->expires < now)
+		{
+			char msg[200];
+			snprintf(msg, sizeof(msg), "mapping %u expired", index);
+			log(msg, l);
+			i->action = mapping_t::action_add;
+			if (m_next_refresh == index) m_next_refresh = -1;
+			update_mapping(index, l);
+		}
+		else if (i->expires < min_expire)
 		{
 			min_expire = i->expires;
-			min_index = i - m_mappings.begin();
+			min_index = index;
 		}
 	}
 

src/peer_connection.cpp

@@ -3732,6 +3732,7 @@ namespace libtorrent
 		}
 
 		if (!m_download_queue.empty()
+			&& m_quota[download_channel] > 0
 			&& now > m_requested + seconds(m_ses.settings().request_timeout
 			+ m_timeout_extend))
 		{
@@ -3816,6 +3817,7 @@ namespace libtorrent
 		if (piece_timeout < rate_limit_timeout) piece_timeout = rate_limit_timeout;
 
 		if (!m_download_queue.empty()
+			&& m_quota[download_channel] > 0
 			&& now - m_last_piece > seconds(piece_timeout + m_timeout_extend))
 		{
 			// this peer isn't sending the pieces we've
@@ -4367,6 +4369,22 @@ namespace libtorrent
 			return;
 		}
 
+		error_code ec;
+		size_t bytes_transferred = try_read(read_sync, ec);
+
+		if (ec == asio::error::would_block)
+		{
+			try_read(read_async, ec);
+		}
+		else
+		{
+			m_channel_state[download_channel] = peer_info::bw_network;
+			on_receive_data_nolock(ec, bytes_transferred);
+		}
+	}
+
+	size_t peer_connection::try_read(sync_t s, error_code& ec)
+	{
 		TORRENT_ASSERT(m_packet_size > 0);
 		int max_receive = m_packet_size - m_recv_pos;
 		TORRENT_ASSERT(max_receive >= 0);
@@ -4378,40 +4396,42 @@ namespace libtorrent
 		if (max_receive > quota_left)
 			max_receive = quota_left;
 
-		if (max_receive == 0) return;
+		if (max_receive == 0)
+		{
+			ec = asio::error::would_block;
+			return 0;
+		}
 
 		TORRENT_ASSERT(m_recv_pos >= 0);
 		TORRENT_ASSERT(m_packet_size > 0);
-		TORRENT_ASSERT(can_read());
-#ifdef TORRENT_VERBOSE_LOGGING
-		(*m_logger) << time_now_string() << " *** ASYNC_READ [ max: " << max_receive << " bytes ]\n";
-#endif
+
+		if (!can_read())
+		{
+			ec = asio::error::would_block;
+			return 0;
+		}
 
 		int regular_buffer_size = m_packet_size - m_disk_recv_buffer_size;
 
 		if (int(m_recv_buffer.size()) < regular_buffer_size)
 			m_recv_buffer.resize(regular_buffer_size);
 
+		boost::array<asio::mutable_buffer, 2> vec;
+		int num_bufs = 0;
 		if (!m_disk_recv_buffer || regular_buffer_size >= m_recv_pos + max_receive)
 		{
 			// only receive into regular buffer
 			TORRENT_ASSERT(m_recv_pos + max_receive <= int(m_recv_buffer.size()));
-			m_socket->async_read_some(asio::buffer(&m_recv_buffer[m_recv_pos]
-				, max_receive)
-				, make_read_handler(
-					boost::bind(&peer_connection::on_receive_data, self(), _1, _2)
-				));
+			vec[0] = asio::buffer(&m_recv_buffer[m_recv_pos], max_receive);
+			num_bufs = 1;
 		}
 		else if (m_recv_pos >= regular_buffer_size)
 		{
 			// only receive into disk buffer
 			TORRENT_ASSERT(m_recv_pos - regular_buffer_size >= 0);
 			TORRENT_ASSERT(m_recv_pos - regular_buffer_size + max_receive <= m_disk_recv_buffer_size);
-			m_socket->async_read_some(asio::buffer(m_disk_recv_buffer.get() + m_recv_pos - regular_buffer_size
-				, max_receive)
-				, make_read_handler(
-					boost::bind(&peer_connection::on_receive_data, self(), _1, _2)
-				));
+			vec[0] = asio::buffer(m_disk_recv_buffer.get() + m_recv_pos - regular_buffer_size, max_receive);
+			num_bufs = 1;
 		}
 		else
 		{
@@ -4421,16 +4441,49 @@ namespace libtorrent
 			TORRENT_ASSERT(max_receive - regular_buffer_size
 				+ m_recv_pos <= m_disk_recv_buffer_size);
 
-			boost::array<asio::mutable_buffer, 2> vec;
 			vec[0] = asio::buffer(&m_recv_buffer[m_recv_pos]
 				, regular_buffer_size - m_recv_pos);
 			vec[1] = asio::buffer(m_disk_recv_buffer.get()
 				, max_receive - regular_buffer_size + m_recv_pos);
-			m_socket->async_read_some(
-				vec, make_read_handler(
-					boost::bind(&peer_connection::on_receive_data, self(), _1, _2)));
+			num_bufs = 2;
 		}
-		m_channel_state[download_channel] = peer_info::bw_network;
+
+		if (s == read_async)
+		{
+			m_channel_state[download_channel] = peer_info::bw_network;
+#ifdef TORRENT_VERBOSE_LOGGING
+			(*m_logger) << time_now_string() << " *** ASYNC_READ [ max: " << max_receive << " bytes ]\n";
+#endif
+
+			if (num_bufs == 1)
+			{
+				m_socket->async_read_some(
+					asio::mutable_buffers_1(vec[0]), make_read_handler(
+						boost::bind(&peer_connection::on_receive_data, self(), _1, _2)));
+			}
+			else
+			{
+				m_socket->async_read_some(
+					vec, make_read_handler(
+						boost::bind(&peer_connection::on_receive_data, self(), _1, _2)));
+			}
+			return 0;
+		}
+
+		size_t ret = 0;
+		if (num_bufs == 1)
+		{
+			ret = m_socket->read_some(asio::mutable_buffers_1(vec[0]), ec);
+		}
+		else
+		{
+			ret = m_socket->read_some(vec, ec);
+		}
+
+#ifdef TORRENT_VERBOSE_LOGGING
+		(*m_logger) << time_now_string() << " *** SYNC_READ [ max: " << max_receive << " ret: " << ret << " e: " << ec.message() << " ]\n";
+#endif
+		return ret;
 	}
 
 #ifndef TORRENT_DISABLE_ENCRYPTION
@@ -4573,6 +4626,12 @@ namespace libtorrent
 		, std::size_t bytes_transferred)
 	{
 		mutex::scoped_lock l(m_ses.m_mutex);
+		on_receive_data_nolock(error, bytes_transferred);
+	}
+
+	void peer_connection::on_receive_data_nolock(const error_code& error
+		, std::size_t bytes_transferred)
+	{
 
 		INVARIANT_CHECK;
 
@@ -4651,54 +4710,9 @@ namespace libtorrent
 			}
 
 			if (m_recv_pos >= m_soft_packet_size) m_soft_packet_size = 0;
-			max_receive = m_packet_size - m_recv_pos;
-			TORRENT_ASSERT(max_receive >= 0);
-			if (m_soft_packet_size && max_receive > m_soft_packet_size - m_recv_pos)
-				max_receive = m_soft_packet_size - m_recv_pos;
-			int quota_left = m_quota[download_channel];
-			if (max_receive > quota_left)
-				max_receive = quota_left;
 
-			if (max_receive == 0) break;
-
-			int regular_buffer_size = m_packet_size - m_disk_recv_buffer_size;
-
-			if (int(m_recv_buffer.size()) < regular_buffer_size)
-				m_recv_buffer.resize(regular_buffer_size);
-
-			error_code ec;	
-			if (!m_disk_recv_buffer || regular_buffer_size >= m_recv_pos + max_receive)
-			{
-				// only receive into regular buffer
-				TORRENT_ASSERT(m_recv_pos + max_receive <= int(m_recv_buffer.size()));
-				bytes_transferred = m_socket->read_some(asio::buffer(&m_recv_buffer[m_recv_pos]
-					, max_receive), ec);
-			}
-			else if (m_recv_pos >= regular_buffer_size)
-			{
-				// only receive into disk buffer
-				TORRENT_ASSERT(m_recv_pos - regular_buffer_size >= 0);
-				TORRENT_ASSERT(m_recv_pos - regular_buffer_size + max_receive <= m_disk_recv_buffer_size);
-				bytes_transferred = m_socket->read_some(asio::buffer(m_disk_recv_buffer.get()
-					+ m_recv_pos - regular_buffer_size, (std::min)(m_packet_size
-					- m_recv_pos, max_receive)), ec);
-			}
-			else
-			{
-				// receive into both regular and disk buffer
-				TORRENT_ASSERT(max_receive + m_recv_pos > regular_buffer_size);
-				TORRENT_ASSERT(m_recv_pos < regular_buffer_size);
-				TORRENT_ASSERT(max_receive - regular_buffer_size
-					+ m_recv_pos <= m_disk_recv_buffer_size);
-
-				boost::array<asio::mutable_buffer, 2> vec;
-				vec[0] = asio::buffer(&m_recv_buffer[m_recv_pos]
-					, regular_buffer_size - m_recv_pos);
-				vec[1] = asio::buffer(m_disk_recv_buffer.get()
-					, (std::min)(m_disk_recv_buffer_size
-					, max_receive - regular_buffer_size + m_recv_pos));
-				bytes_transferred = m_socket->read_some(vec, ec);
-			}
+			error_code ec;
+			bytes_transferred = try_read(read_sync, ec);
 			if (ec && ec != asio::error::would_block)
 			{
 				m_statistics.trancieve_ip_packet(bytes_in_loop, m_remote.address().is_v6());
@@ -4717,7 +4731,7 @@ namespace libtorrent
 		}
 
 		m_statistics.trancieve_ip_packet(bytes_in_loop, m_remote.address().is_v6());
-		setup_receive();	
+		setup_receive();
 	}
 
 	bool peer_connection::can_write() const

src/tracker_manager.cpp

@@ -105,9 +105,9 @@ namespace libtorrent
 		time_duration completion_timeout = now - m_start_time;
 		
 		if (m_read_timeout
-			< total_seconds(receive_timeout)
+			<= total_seconds(receive_timeout)
 			|| m_completion_timeout
-			< total_seconds(completion_timeout))
+			<= total_seconds(completion_timeout))
 		{
 			on_timeout();
 			return;