From 2d9838f467013d5397b6daf83afb5ccea92065a4 Mon Sep 17 00:00:00 2001 From: Josh Blum Date: Sun, 20 Feb 2011 01:13:03 -0800 Subject: udp: update docs for transport, create common header for wait implementation Reimplemented simple udp transport with one impl class. Moved wait for ready/select implementation into common header. Important note on select, timeval should have usecs < 1 second or it may error on some platforms. Fixed in this implementation. --- host/lib/transport/udp_zero_copy.cpp | 304 +++++++++++++++++++++++++++++++++++ 1 file changed, 304 insertions(+) create mode 100644 host/lib/transport/udp_zero_copy.cpp (limited to 'host/lib/transport/udp_zero_copy.cpp') diff --git a/host/lib/transport/udp_zero_copy.cpp b/host/lib/transport/udp_zero_copy.cpp new file mode 100644 index 000000000..793fc6fba --- /dev/null +++ b/host/lib/transport/udp_zero_copy.cpp @@ -0,0 +1,304 @@ +// +// Copyright 2010-2011 Ettus Research LLC +// +// This program is free software: you can redistribute it and/or modify +// it under the terms of the GNU General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// This program is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License +// along with this program. If not, see . +// + +#include "udp_common.hpp" +#include +#include //mtu +#include +#include +#include +#include +#include +#include + +using namespace uhd; +using namespace uhd::transport; +namespace asio = boost::asio; + +//A reasonable number of frames for send/recv and async/sync +static const size_t DEFAULT_NUM_FRAMES = 32; + +/*********************************************************************** + * Reusable managed receiver buffer: + * - Initialize with memory and a release callback. + * - Call get new with a length in bytes to re-use. + **********************************************************************/ +class udp_zero_copy_asio_mrb : public managed_recv_buffer{ +public: + typedef boost::function release_cb_type; + + udp_zero_copy_asio_mrb(void *mem, const release_cb_type &release_cb): + _mem(mem), _len(0), _release_cb(release_cb){/* NOP */} + + void release(void){ + if (_len == 0) return; + this->_release_cb(this); + _len = 0; + } + + sptr get_new(size_t len){ + _len = len; + return sptr(this, &udp_zero_copy_asio_mrb::fake_deleter); + } + + template T cast(void) const{return static_cast(_mem);} + +private: + static void fake_deleter(void *obj){ + static_cast(obj)->release(); + } + + const void *get_buff(void) const{return _mem;} + size_t get_size(void) const{return _len;} + + void *_mem; + size_t _len; + release_cb_type _release_cb; +}; + +/*********************************************************************** + * Reusable managed send buffer: + * - Initialize with memory and a commit callback. + * - Call get new with a length in bytes to re-use. + **********************************************************************/ +class udp_zero_copy_asio_msb : public managed_send_buffer{ +public: + typedef boost::function commit_cb_type; + + udp_zero_copy_asio_msb(void *mem, const commit_cb_type &commit_cb): + _mem(mem), _len(0), _commit_cb(commit_cb){/* NOP */} + + void commit(size_t len){ + if (_len == 0) return; + this->_commit_cb(this, len); + _len = 0; + } + + sptr get_new(size_t len){ + _len = len; + return sptr(this, &udp_zero_copy_asio_msb::fake_deleter); + } + +private: + static void fake_deleter(void *obj){ + static_cast(obj)->commit(0); + } + + void *get_buff(void) const{return _mem;} + size_t get_size(void) const{return _len;} + + void *_mem; + size_t _len; + commit_cb_type _commit_cb; +}; + +/*********************************************************************** + * Zero Copy UDP implementation with ASIO: + * This is the portable zero copy implementation for systems + * where a faster, platform specific solution is not available. + * However, it is not a true zero copy implementation as each + * send and recv requires a copy operation to/from userspace. + **********************************************************************/ +class udp_zero_copy_asio_impl : public udp_zero_copy{ +public: + typedef boost::shared_ptr sptr; + + udp_zero_copy_asio_impl( + const std::string &addr, + const std::string &port, + const device_addr_t &hints + ): + _recv_frame_size(size_t(hints.cast("recv_frame_size", udp_simple::mtu))), + _num_recv_frames(size_t(hints.cast("num_recv_frames", DEFAULT_NUM_FRAMES))), + _send_frame_size(size_t(hints.cast("send_frame_size", udp_simple::mtu))), + _num_send_frames(size_t(hints.cast("num_send_frames", DEFAULT_NUM_FRAMES))), + _recv_buffer_pool(buffer_pool::make(_num_recv_frames, _recv_frame_size)), + _send_buffer_pool(buffer_pool::make(_num_send_frames, _send_frame_size)), + _pending_recv_buffs(_num_recv_frames), + _pending_send_buffs(_num_send_frames) + { + //std::cout << boost::format("Creating udp transport for %s %s") % addr % port << std::endl; + + //resolve the address + asio::ip::udp::resolver resolver(_io_service); + asio::ip::udp::resolver::query query(asio::ip::udp::v4(), addr, port); + asio::ip::udp::endpoint receiver_endpoint = *resolver.resolve(query); + + //create, open, and connect the socket + _socket = new asio::ip::udp::socket(_io_service); + _socket->open(asio::ip::udp::v4()); + _socket->connect(receiver_endpoint); + _sock_fd = _socket->native(); + + //allocate re-usable managed receive buffers + for (size_t i = 0; i < get_num_recv_frames(); i++){ + _mrb_pool.push_back(udp_zero_copy_asio_mrb(_recv_buffer_pool->at(i), + boost::bind(&udp_zero_copy_asio_impl::release, this, _1)) + ); + handle_recv(&_mrb_pool.back()); + } + + //allocate re-usable managed send buffers + for (size_t i = 0; i < get_num_send_frames(); i++){ + _msb_pool.push_back(udp_zero_copy_asio_msb(_send_buffer_pool->at(i), + boost::bind(&udp_zero_copy_asio_impl::commit, this, _1, _2)) + ); + handle_send(&_msb_pool.back()); + } + } + + ~udp_zero_copy_asio_impl(void){ + delete _socket; + } + + //get size for internal socket buffer + template size_t get_buff_size(void) const{ + Opt option; + _socket->get_option(option); + return option.value(); + } + + //set size for internal socket buffer + template size_t resize_buff(size_t num_bytes){ + Opt option(num_bytes); + _socket->set_option(option); + return get_buff_size(); + } + + /******************************************************************* + * Receive implementation: + * + * Use select to perform a blocking receive with timeout. + * Return the managed receive buffer with the new length. + * When the caller is finished with the managed buffer, + * the managed receive buffer is released back into the queue. + ******************************************************************/ + managed_recv_buffer::sptr get_recv_buff(double timeout){ + udp_zero_copy_asio_mrb *mrb = NULL; + bool recv_ready = wait_for_recv(_sock_fd, timeout); + if (recv_ready and _pending_recv_buffs.pop_with_timed_wait(mrb, timeout)){ + return mrb->get_new(::recv(_sock_fd, mrb->cast(), _recv_frame_size, 0)); + } + return managed_recv_buffer::sptr(); + } + + UHD_INLINE void handle_recv(udp_zero_copy_asio_mrb *mrb){ + _pending_recv_buffs.push_with_haste(mrb); + } + + void release(udp_zero_copy_asio_mrb *mrb){ + handle_recv(mrb); + } + + size_t get_num_recv_frames(void) const {return _num_recv_frames;} + size_t get_recv_frame_size(void) const {return _recv_frame_size;} + + /******************************************************************* + * Send implementation: + * + * Get a managed receive buffer immediately with max length set. + * The caller will fill the buffer and commit it when finished. + * The commit routine will perform a blocking send operation, + * and push the managed send buffer back into the queue. + ******************************************************************/ + managed_send_buffer::sptr get_send_buff(double timeout){ + udp_zero_copy_asio_msb *msb = NULL; + if (_pending_send_buffs.pop_with_timed_wait(msb, timeout)){ + return msb->get_new(_send_frame_size); + } + return managed_send_buffer::sptr(); + } + + UHD_INLINE void handle_send(udp_zero_copy_asio_msb *msb){ + _pending_send_buffs.push_with_haste(msb); + } + + void commit(udp_zero_copy_asio_msb *msb, size_t len){ + ::send(_sock_fd, msb->cast(), len, 0); + handle_send(msb); + } + + size_t get_num_send_frames(void) const {return _num_send_frames;} + size_t get_send_frame_size(void) const {return _send_frame_size;} + +private: + //memory management -> buffers and fifos + const size_t _recv_frame_size, _num_recv_frames; + const size_t _send_frame_size, _num_send_frames; + buffer_pool::sptr _recv_buffer_pool, _send_buffer_pool; + bounded_buffer _pending_recv_buffs; + bounded_buffer _pending_send_buffs; + std::list _msb_pool; + std::list _mrb_pool; + + //asio guts -> socket and service + asio::io_service _io_service; + asio::ip::udp::socket *_socket; + int _sock_fd; +}; + +/*********************************************************************** + * UDP zero copy make function + **********************************************************************/ +template static void resize_buff_helper( + udp_zero_copy_asio_impl::sptr udp_trans, + const size_t target_size, + const std::string &name +){ + std::string help_message; + #if defined(UHD_PLATFORM_LINUX) + help_message = str(boost::format( + "Please run: sudo sysctl -w net.core.%smem_max=%d\n" + ) % ((name == "recv")?"r":"w") % target_size); + #endif /*defined(UHD_PLATFORM_LINUX)*/ + + //resize the buffer if size was provided + if (target_size > 0){ + size_t actual_size = udp_trans->resize_buff(target_size); + if (target_size != actual_size) std::cout << boost::format( + "Target %s sock buff size: %d bytes\n" + "Actual %s sock buff size: %d bytes" + ) % name % target_size % name % actual_size << std::endl; + else std::cout << boost::format( + "Current %s sock buff size: %d bytes" + ) % name % actual_size << std::endl; + if (actual_size < target_size) uhd::warning::post(str(boost::format( + "The %s buffer could not be resized sufficiently.\n" + "See the transport application notes on buffer resizing.\n%s" + ) % name % help_message)); + } +} + +udp_zero_copy::sptr udp_zero_copy::make( + const std::string &addr, + const std::string &port, + const device_addr_t &hints +){ + udp_zero_copy_asio_impl::sptr udp_trans( + new udp_zero_copy_asio_impl(addr, port, hints) + ); + + //extract buffer size hints from the device addr + size_t recv_buff_size = size_t(hints.cast("recv_buff_size", 0.0)); + size_t send_buff_size = size_t(hints.cast("send_buff_size", 0.0)); + + //call the helper to resize send and recv buffers + resize_buff_helper(udp_trans, recv_buff_size, "recv"); + resize_buff_helper (udp_trans, send_buff_size, "send"); + + return udp_trans; +} -- cgit v1.2.3 From 4787c77bb089bf50a47207bbad55bd65a44769e4 Mon Sep 17 00:00:00 2001 From: Josh Blum Date: Sun, 20 Feb 2011 02:41:03 -0800 Subject: udp: try non-blocking recv first for performance --- host/lib/transport/udp_common.hpp | 4 +++- host/lib/transport/udp_simple.cpp | 4 +--- host/lib/transport/udp_zero_copy.cpp | 24 ++++++++++++++---------- 3 files changed, 18 insertions(+), 14 deletions(-) (limited to 'host/lib/transport/udp_zero_copy.cpp') diff --git a/host/lib/transport/udp_common.hpp b/host/lib/transport/udp_common.hpp index 44067b5dc..47775d9c4 100644 --- a/host/lib/transport/udp_common.hpp +++ b/host/lib/transport/udp_common.hpp @@ -23,13 +23,15 @@ namespace uhd{ namespace transport{ + typedef boost::shared_ptr socket_sptr; + /*! * Wait for the socket to become ready for a receive operation. * \param sock_fd the open socket file descriptor * \param timeout the timeout duration in seconds * \return true when the socket is ready for receive */ - UHD_INLINE bool wait_for_recv(int sock_fd, double timeout){ + UHD_INLINE bool wait_for_recv_ready(int sock_fd, double timeout){ //setup timeval for timeout timeval tv; //If the tv_usec > 1 second on some platforms, select will diff --git a/host/lib/transport/udp_simple.cpp b/host/lib/transport/udp_simple.cpp index 094f570ff..1ee036d52 100644 --- a/host/lib/transport/udp_simple.cpp +++ b/host/lib/transport/udp_simple.cpp @@ -28,8 +28,6 @@ namespace asio = boost::asio; **********************************************************************/ class udp_simple_impl : public udp_simple{ public: - typedef boost::shared_ptr socket_sptr; - udp_simple_impl( const std::string &addr, const std::string &port, bool bcast, bool connect ):_connected(connect){ @@ -58,7 +56,7 @@ public: } size_t recv(const asio::mutable_buffer &buff, double timeout){ - if (not wait_for_recv(_socket->native(), timeout)) return 0; + if (not wait_for_recv_ready(_socket->native(), timeout)) return 0; return _socket->receive(asio::buffer(buff)); } diff --git a/host/lib/transport/udp_zero_copy.cpp b/host/lib/transport/udp_zero_copy.cpp index 793fc6fba..dda3bb547 100644 --- a/host/lib/transport/udp_zero_copy.cpp +++ b/host/lib/transport/udp_zero_copy.cpp @@ -139,7 +139,7 @@ public: asio::ip::udp::endpoint receiver_endpoint = *resolver.resolve(query); //create, open, and connect the socket - _socket = new asio::ip::udp::socket(_io_service); + _socket = socket_sptr(new asio::ip::udp::socket(_io_service)); _socket->open(asio::ip::udp::v4()); _socket->connect(receiver_endpoint); _sock_fd = _socket->native(); @@ -161,10 +161,6 @@ public: } } - ~udp_zero_copy_asio_impl(void){ - delete _socket; - } - //get size for internal socket buffer template size_t get_buff_size(void) const{ Opt option; @@ -182,16 +178,24 @@ public: /******************************************************************* * Receive implementation: * - * Use select to perform a blocking receive with timeout. + * Perform a non-blocking receive for performance, + * and then fall back to a blocking receive with timeout. * Return the managed receive buffer with the new length. * When the caller is finished with the managed buffer, * the managed receive buffer is released back into the queue. ******************************************************************/ managed_recv_buffer::sptr get_recv_buff(double timeout){ udp_zero_copy_asio_mrb *mrb = NULL; - bool recv_ready = wait_for_recv(_sock_fd, timeout); - if (recv_ready and _pending_recv_buffs.pop_with_timed_wait(mrb, timeout)){ - return mrb->get_new(::recv(_sock_fd, mrb->cast(), _recv_frame_size, 0)); + if (_pending_recv_buffs.pop_with_timed_wait(mrb, timeout)){ + + #ifdef MSG_DONTWAIT //try a non-blocking recv() if supported + ssize_t ret = ::recv(_sock_fd, mrb->cast(), _recv_frame_size, MSG_DONTWAIT); + if (ret > 0) return mrb->get_new(ret); + #endif + + if (wait_for_recv_ready(_sock_fd, timeout)) return mrb->get_new( + ::recv(_sock_fd, mrb->cast(), _recv_frame_size, 0) + ); } return managed_recv_buffer::sptr(); } @@ -247,7 +251,7 @@ private: //asio guts -> socket and service asio::io_service _io_service; - asio::ip::udp::socket *_socket; + socket_sptr _socket; int _sock_fd; }; -- cgit v1.2.3