diff options
Diffstat (limited to 'host/lib/transport/libusb1_zero_copy.cpp')
| -rw-r--r-- | host/lib/transport/libusb1_zero_copy.cpp | 297 |
1 files changed, 297 insertions, 0 deletions
diff --git a/host/lib/transport/libusb1_zero_copy.cpp b/host/lib/transport/libusb1_zero_copy.cpp new file mode 100644 index 000000000..28d6cdd5b --- /dev/null +++ b/host/lib/transport/libusb1_zero_copy.cpp @@ -0,0 +1,297 @@ +// +// 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 <http://www.gnu.org/licenses/>. +// + +#include "libusb1_base.hpp" +#include <uhd/transport/usb_zero_copy.hpp> +#include <uhd/transport/buffer_pool.hpp> +#include <uhd/utils/msg.hpp> +#include <uhd/exception.hpp> +#include <boost/foreach.hpp> +#include <boost/thread/thread.hpp> +#include <list> + +using namespace uhd; +using namespace uhd::transport; + +static const size_t DEFAULT_NUM_XFERS = 16; //num xfers +static const size_t DEFAULT_XFER_SIZE = 32*512; //bytes + +//! Define LIBUSB_CALL when its missing (non-windows) +#ifndef LIBUSB_CALL + #define LIBUSB_CALL +#endif /*LIBUSB_CALL*/ + +/*! + * All libusb callback functions should be marked with the LIBUSB_CALL macro + * to ensure that they are compiled with the same calling convention as libusb. + */ + +//! helper function: handles all async callbacks +static void LIBUSB_CALL libusb_async_cb(libusb_transfer *lut){ + *(static_cast<bool *>(lut->user_data)) = true; +} + +/*! + * Wait for a managed buffer to become complete. + * + * This routine processes async events until the transaction completes. + * We must call the libusb handle events in a loop because the handler + * may complete managed buffers other than the one we are waiting on. + * + * We cannot determine if handle events timed out or processed an event. + * Therefore, the timeout condition is handled by using boost system time. + * + * \param ctx the libusb context structure + * \param timeout the wait timeout in seconds + * \param completed a reference to the completed flag + * \return true for completion, false for timeout + */ +UHD_INLINE bool wait_for_completion(libusb_context *ctx, const double timeout, bool &completed){ + const boost::system_time timeout_time = boost::get_system_time() + boost::posix_time::microseconds(long(timeout*1000000)); + + while (not completed and (boost::get_system_time() < timeout_time)){ + timeval tv; + tv.tv_sec = 0; + tv.tv_usec = 10000; /*10ms*/ + libusb_handle_events_timeout(ctx, &tv); + } + + return completed; +} + +/*********************************************************************** + * Reusable managed receiver buffer: + * - Associated with a particular libusb transfer struct. + * - Submits the transfer to libusb in the release method. + **********************************************************************/ +class libusb_zero_copy_mrb : public managed_recv_buffer{ +public: + libusb_zero_copy_mrb(libusb_transfer *lut): + _ctx(libusb::session::get_global_session()->get_context()), + _lut(lut), _expired(false) { /* NOP */ } + + void release(void){ + if (_expired) return; + completed = false; + UHD_ASSERT_THROW(libusb_submit_transfer(_lut) == 0); + _expired = true; + } + + sptr get_new(const double timeout, size_t &index){ + if (wait_for_completion(_ctx, timeout, completed)){ + index++; + _expired = false; + return make_managed_buffer(this); + } + return managed_recv_buffer::sptr(); + } + + bool completed; + +private: + const void *get_buff(void) const{return _lut->buffer;} + size_t get_size(void) const{return _lut->actual_length;} + + libusb_context *_ctx; + libusb_transfer *_lut; + bool _expired; +}; + +/*********************************************************************** + * Reusable managed send buffer: + * - Associated with a particular libusb transfer struct. + * - Submits the transfer to libusb in the commit method. + **********************************************************************/ +class libusb_zero_copy_msb : public managed_send_buffer{ +public: + libusb_zero_copy_msb(libusb_transfer *lut): + _ctx(libusb::session::get_global_session()->get_context()), + _lut(lut), _expired(false) { /* NOP */ } + + void commit(size_t len){ + if (_expired) return; + completed = false; + _lut->length = len; + if (len == 0) libusb_async_cb(_lut); + else UHD_ASSERT_THROW(libusb_submit_transfer(_lut) == 0); + _expired = true; + } + + sptr get_new(const double timeout, size_t &index){ + if (wait_for_completion(_ctx, timeout, completed)){ + index++; + _expired = false; + return make_managed_buffer(this); + } + return managed_send_buffer::sptr(); + } + + bool completed; + +private: + void *get_buff(void) const{return _lut->buffer;} + size_t get_size(void) const{return _lut->length;} + + libusb_context *_ctx; + libusb_transfer *_lut; + bool _expired; +}; + +/*********************************************************************** + * USB zero_copy device class + **********************************************************************/ +class libusb_zero_copy_impl : public usb_zero_copy{ +public: + + libusb_zero_copy_impl( + libusb::device_handle::sptr handle, + const size_t recv_interface, + const size_t recv_endpoint, + const size_t send_interface, + const size_t send_endpoint, + const device_addr_t &hints + ): + _handle(handle), + _recv_frame_size(size_t(hints.cast<double>("recv_frame_size", DEFAULT_XFER_SIZE))), + _num_recv_frames(size_t(hints.cast<double>("num_recv_frames", DEFAULT_NUM_XFERS))), + _send_frame_size(size_t(hints.cast<double>("send_frame_size", DEFAULT_XFER_SIZE))), + _num_send_frames(size_t(hints.cast<double>("num_send_frames", DEFAULT_NUM_XFERS))), + _recv_buffer_pool(buffer_pool::make(_num_recv_frames, _recv_frame_size)), + _send_buffer_pool(buffer_pool::make(_num_send_frames, _send_frame_size)), + _next_recv_buff_index(0), + _next_send_buff_index(0) + { + _handle->claim_interface(recv_interface); + _handle->claim_interface(send_interface); + + //allocate libusb transfer structs and managed receive buffers + for (size_t i = 0; i < get_num_recv_frames(); i++){ + + libusb_transfer *lut = libusb_alloc_transfer(0); + UHD_ASSERT_THROW(lut != NULL); + + _mrb_pool.push_back(boost::shared_ptr<libusb_zero_copy_mrb>(new libusb_zero_copy_mrb(lut))); + + libusb_fill_bulk_transfer( + lut, // transfer + _handle->get(), // dev_handle + (recv_endpoint & 0x7f) | 0x80, // endpoint + static_cast<unsigned char *>(_recv_buffer_pool->at(i)), // buffer + this->get_recv_frame_size(), // length + libusb_transfer_cb_fn(&libusb_async_cb), // callback + static_cast<void *>(&_mrb_pool.back()->completed), // user_data + 0 // timeout (ms) + ); + + _all_luts.push_back(lut); + _mrb_pool.back()->release(); + } + + //allocate libusb transfer structs and managed send buffers + for (size_t i = 0; i < get_num_send_frames(); i++){ + + libusb_transfer *lut = libusb_alloc_transfer(0); + UHD_ASSERT_THROW(lut != NULL); + + _msb_pool.push_back(boost::shared_ptr<libusb_zero_copy_msb>(new libusb_zero_copy_msb(lut))); + + libusb_fill_bulk_transfer( + lut, // transfer + _handle->get(), // dev_handle + (send_endpoint & 0x7f) | 0x00, // endpoint + static_cast<unsigned char *>(_send_buffer_pool->at(i)), // buffer + this->get_send_frame_size(), // length + libusb_transfer_cb_fn(&libusb_async_cb), // callback + static_cast<void *>(&_msb_pool.back()->completed), // user_data + 0 // timeout + ); + + _all_luts.push_back(lut); + _msb_pool.back()->commit(0); + } + } + + ~libusb_zero_copy_impl(void){ + libusb_context *ctx = libusb::session::get_global_session()->get_context(); + + //cancel all transfers + BOOST_FOREACH(libusb_transfer *lut, _all_luts){ + libusb_cancel_transfer(lut); + } + + //process all transfers until timeout occurs + bool completed = false; + wait_for_completion(ctx, 0.01, completed); + + //free all transfers + BOOST_FOREACH(libusb_transfer *lut, _all_luts){ + libusb_free_transfer(lut); + } + + } + + managed_recv_buffer::sptr get_recv_buff(double timeout){ + if (_next_recv_buff_index == _num_recv_frames) _next_recv_buff_index = 0; + return _mrb_pool[_next_recv_buff_index]->get_new(timeout, _next_recv_buff_index); + } + + managed_send_buffer::sptr get_send_buff(double timeout){ + if (_next_send_buff_index == _num_send_frames) _next_send_buff_index = 0; + return _msb_pool[_next_send_buff_index]->get_new(timeout, _next_send_buff_index); + } + + size_t get_num_recv_frames(void) const { return _num_recv_frames; } + size_t get_num_send_frames(void) const { return _num_send_frames; } + + size_t get_recv_frame_size(void) const { return _recv_frame_size; } + size_t get_send_frame_size(void) const { return _send_frame_size; } + +private: + libusb::device_handle::sptr _handle; + const size_t _recv_frame_size, _num_recv_frames; + const size_t _send_frame_size, _num_send_frames; + + //! Storage for transfer related objects + buffer_pool::sptr _recv_buffer_pool, _send_buffer_pool; + std::vector<boost::shared_ptr<libusb_zero_copy_mrb> > _mrb_pool; + std::vector<boost::shared_ptr<libusb_zero_copy_msb> > _msb_pool; + size_t _next_recv_buff_index, _next_send_buff_index; + + //! a list of all transfer structs we allocated + std::list<libusb_transfer *> _all_luts; + + +}; + +/*********************************************************************** + * USB zero_copy make functions + **********************************************************************/ +usb_zero_copy::sptr usb_zero_copy::make( + usb_device_handle::sptr handle, + const size_t recv_interface, + const size_t recv_endpoint, + const size_t send_interface, + const size_t send_endpoint, + const device_addr_t &hints +){ + libusb::device_handle::sptr dev_handle(libusb::device_handle::get_cached_handle( + boost::static_pointer_cast<libusb::special_handle>(handle)->get_device() + )); + return sptr(new libusb_zero_copy_impl( + dev_handle, recv_interface, recv_endpoint, send_interface, send_endpoint, hints + )); +} |