diff options
Diffstat (limited to 'host/lib/usrp')
-rw-r--r-- | host/lib/usrp/b100/CMakeLists.txt | 3 | ||||
-rw-r--r-- | host/lib/usrp/b100/b100_impl.cpp | 4 | ||||
-rw-r--r-- | host/lib/usrp/b100/b100_impl.hpp | 20 | ||||
-rw-r--r-- | host/lib/usrp/b100/usb_zero_copy_wrapper.cpp | 239 |
4 files changed, 262 insertions, 4 deletions
diff --git a/host/lib/usrp/b100/CMakeLists.txt b/host/lib/usrp/b100/CMakeLists.txt index d2c33b512..bcc5ac74d 100644 --- a/host/lib/usrp/b100/CMakeLists.txt +++ b/host/lib/usrp/b100/CMakeLists.txt @@ -1,5 +1,5 @@ # -# Copyright 2011-2012 Ettus Research LLC +# Copyright 2011-2013 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 @@ -31,5 +31,6 @@ IF(ENABLE_B100) ${CMAKE_CURRENT_SOURCE_DIR}/codec_ctrl.cpp ${CMAKE_CURRENT_SOURCE_DIR}/dboard_iface.cpp ${CMAKE_CURRENT_SOURCE_DIR}/io_impl.cpp + ${CMAKE_CURRENT_SOURCE_DIR}/usb_zero_copy_wrapper.cpp ) ENDIF(ENABLE_B100) diff --git a/host/lib/usrp/b100/b100_impl.cpp b/host/lib/usrp/b100/b100_impl.cpp index 1673f5f3c..20933a2fe 100644 --- a/host/lib/usrp/b100/b100_impl.cpp +++ b/host/lib/usrp/b100/b100_impl.cpp @@ -1,5 +1,5 @@ // -// Copyright 2012 Ettus Research LLC +// Copyright 2012-2013 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 @@ -245,7 +245,7 @@ b100_impl::b100_impl(const device_addr_t &device_addr){ const size_t rx_lut_size = size_t(data_xport_args.cast<double>("recv_frame_size", 0.0)); _fifo_ctrl->poke32(TOREG(SR_PADDER+0), rx_lut_size/sizeof(boost::uint32_t)); - _data_transport = usb_zero_copy::make_wrapper( + _data_transport = usb_zero_copy_make_wrapper( usb_zero_copy::make( handle, // identifier 2, 6, // IN interface, endpoint diff --git a/host/lib/usrp/b100/b100_impl.hpp b/host/lib/usrp/b100/b100_impl.hpp index 5f4899eb3..f81aa3568 100644 --- a/host/lib/usrp/b100/b100_impl.hpp +++ b/host/lib/usrp/b100/b100_impl.hpp @@ -1,5 +1,5 @@ // -// Copyright 2011-2012 Ettus Research LLC +// Copyright 2011-2013 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 @@ -74,6 +74,24 @@ uhd::usrp::dboard_iface::sptr make_b100_dboard_iface( b100_codec_ctrl::sptr codec ); +/*! + * Make a wrapper around a zero copy implementation. + * The wrapper performs the following functions: + * - Pad commits to the frame boundary + * - Extract multiple packets on recv + * + * When enable multiple receive packets is set to true, + * the implementation inspects the vita length on transfers, + * and may split a single transfer into multiple managed buffers. + * + * \param usb_zc a usb zero copy interface object + * \param usb_frame_boundary bytes per frame + * \return a new zero copy wrapper object + */ +uhd::transport::zero_copy_if::sptr usb_zero_copy_make_wrapper( + uhd::transport::zero_copy_if::sptr usb_zc, size_t usb_frame_boundary = 512 +); + //! Implementation guts class b100_impl : public uhd::device { public: diff --git a/host/lib/usrp/b100/usb_zero_copy_wrapper.cpp b/host/lib/usrp/b100/usb_zero_copy_wrapper.cpp new file mode 100644 index 000000000..2096e4ef4 --- /dev/null +++ b/host/lib/usrp/b100/usb_zero_copy_wrapper.cpp @@ -0,0 +1,239 @@ +// +// Copyright 2011-2012 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 <uhd/transport/usb_zero_copy.hpp> +#include <uhd/transport/buffer_pool.hpp> +#include <uhd/utils/byteswap.hpp> +#include <uhd/utils/msg.hpp> +#include <uhd/utils/tasks.hpp> +#include <uhd/utils/atomic.hpp> +#include <boost/foreach.hpp> +#include <boost/make_shared.hpp> +#include <boost/thread/mutex.hpp> +#include <boost/thread/condition_variable.hpp> +#include <boost/bind.hpp> +#include <vector> +#include <iostream> + +using namespace uhd; +using namespace uhd::transport; + +static const boost::posix_time::time_duration AUTOFLUSH_TIMEOUT(boost::posix_time::milliseconds(1)); + +/*********************************************************************** + * USB zero copy wrapper - managed receive buffer + **********************************************************************/ +class usb_zero_copy_wrapper_mrb : public managed_recv_buffer{ +public: + usb_zero_copy_wrapper_mrb(void){/*NOP*/} + + void release(void){ + _mrb.reset(); //decrement ref count, other MRB's may hold a ref + _claimer.release(); + } + + UHD_INLINE sptr get_new( + managed_recv_buffer::sptr &mrb, size_t &offset_bytes, + const double timeout, size_t &index + ){ + if (not mrb or not _claimer.claim_with_wait(timeout)) return sptr(); + + index++; //advances the caller's buffer + + //hold a copy of the buffer shared pointer + _mrb = mrb; + + //extract this packet's memory address and length in bytes + char *mem = mrb->cast<char *>() + offset_bytes; + const boost::uint32_t *mem32 = reinterpret_cast<const boost::uint32_t *>(mem); + const size_t words32 = (uhd::wtohx(mem32[0]) & 0xffff); //length in words32 (from VRT header) + const size_t len = words32*sizeof(boost::uint32_t); //length in bytes + + //check if this receive buffer has been exhausted + offset_bytes += len; + if (offset_bytes >= mrb->size()) mrb.reset(); //drop caller's ref + else if (uhd::wtohx(mem32[words32]) == 0) mrb.reset(); + + return make(this, mem, len); + } + +private: + managed_recv_buffer::sptr _mrb; + simple_claimer _claimer; +}; + +/*********************************************************************** + * USB zero copy wrapper - managed send buffer + **********************************************************************/ +class usb_zero_copy_wrapper_msb : public managed_send_buffer{ +public: + usb_zero_copy_wrapper_msb(const zero_copy_if::sptr internal, const size_t fragmentation_size): + _internal(internal), _fragmentation_size(fragmentation_size) + { + _ok_to_auto_flush = false; + _task = uhd::task::make(boost::bind(&usb_zero_copy_wrapper_msb::auto_flush, this)); + } + + ~usb_zero_copy_wrapper_msb(void) + { + //ensure the task has exited before anything auto deconstructs + _task.reset(); + } + + void release(void){ + boost::mutex::scoped_lock lock(_mutex); + _ok_to_auto_flush = true; + + //get a reference to the VITA header before incrementing + const boost::uint32_t vita_header = reinterpret_cast<const boost::uint32_t *>(_mem_buffer_tip)[0]; + + _bytes_in_buffer += size(); + _mem_buffer_tip += size(); + + //extract VITA end of packet flag, we must force flush under eof conditions + const bool eop = (uhd::wtohx(vita_header) & (0x1 << 24)) != 0; + const bool full = _bytes_in_buffer >= (_last_send_buff->size() - _fragmentation_size); + if (eop or full){ + _last_send_buff->commit(_bytes_in_buffer); + _last_send_buff.reset(); + + //notify the auto-flusher to restart its timed_wait + lock.unlock(); _cond.notify_one(); + } + } + + UHD_INLINE sptr get_new(const double timeout){ + boost::mutex::scoped_lock lock(_mutex); + _ok_to_auto_flush = false; + + if (not _last_send_buff){ + _last_send_buff = _internal->get_send_buff(timeout); + if (not _last_send_buff) return sptr(); + _mem_buffer_tip = _last_send_buff->cast<char *>(); + _bytes_in_buffer = 0; + } + + return make(this, _mem_buffer_tip, _fragmentation_size); + } + +private: + zero_copy_if::sptr _internal; + const size_t _fragmentation_size; + managed_send_buffer::sptr _last_send_buff; + size_t _bytes_in_buffer; + char *_mem_buffer_tip; + + //private variables for auto flusher + boost::mutex _mutex; + boost::condition_variable _cond; + uhd::task::sptr _task; + bool _ok_to_auto_flush; + + /*! + * The auto flusher ensures that buffers are force committed when + * the user has not called get_new() within a certain time window. + */ + void auto_flush(void) + { + boost::mutex::scoped_lock lock(_mutex); + const bool timeout = not _cond.timed_wait(lock, AUTOFLUSH_TIMEOUT); + if (timeout and _ok_to_auto_flush and _last_send_buff and _bytes_in_buffer != 0) + { + _last_send_buff->commit(_bytes_in_buffer); + _last_send_buff.reset(); + } + } +}; + +/*********************************************************************** + * USB zero copy wrapper implementation + **********************************************************************/ +class usb_zero_copy_wrapper : public usb_zero_copy{ +public: + usb_zero_copy_wrapper(zero_copy_if::sptr usb_zc, const size_t frame_boundary): + _internal_zc(usb_zc), + _frame_boundary(frame_boundary), + _next_recv_buff_index(0) + { + for (size_t i = 0; i < this->get_num_recv_frames(); i++){ + _mrb_pool.push_back(boost::make_shared<usb_zero_copy_wrapper_mrb>()); + } + _the_only_msb = boost::make_shared<usb_zero_copy_wrapper_msb>(usb_zc, frame_boundary); + } + + managed_recv_buffer::sptr get_recv_buff(double timeout){ + //lazy flush mechanism - negative timeout + if (timeout < 0.0) + { + _last_recv_buff.reset(); + while (_internal_zc->get_recv_buff()){} + return managed_recv_buffer::sptr(); + } + + //attempt to get a managed recv buffer + if (not _last_recv_buff){ + _last_recv_buff = _internal_zc->get_recv_buff(timeout); + _last_recv_offset = 0; //reset offset into buffer + } + + //get the buffer to be returned to the user + if (_next_recv_buff_index == _mrb_pool.size()) _next_recv_buff_index = 0; + return _mrb_pool[_next_recv_buff_index]->get_new( + _last_recv_buff, _last_recv_offset, timeout, _next_recv_buff_index + ); + } + + size_t get_num_recv_frames(void) const{ + return _internal_zc->get_num_recv_frames(); + } + + size_t get_recv_frame_size(void) const{ + return std::min(_frame_boundary, _internal_zc->get_recv_frame_size()); + } + + managed_send_buffer::sptr get_send_buff(double timeout){ + return _the_only_msb->get_new(timeout); + } + + size_t get_num_send_frames(void) const{ + return _internal_zc->get_num_send_frames(); + } + + size_t get_send_frame_size(void) const{ + return std::min(_frame_boundary, _internal_zc->get_send_frame_size()); + } + +private: + zero_copy_if::sptr _internal_zc; + size_t _frame_boundary; + std::vector<boost::shared_ptr<usb_zero_copy_wrapper_mrb> > _mrb_pool; + boost::shared_ptr<usb_zero_copy_wrapper_msb> _the_only_msb; + + //state for last recv buffer to create multiple managed buffers + managed_recv_buffer::sptr _last_recv_buff; + size_t _last_recv_offset; + size_t _next_recv_buff_index; +}; + +/*********************************************************************** + * USB zero copy wrapper factory function + **********************************************************************/ +zero_copy_if::sptr usb_zero_copy_make_wrapper( + zero_copy_if::sptr usb_zc, size_t usb_frame_boundary +){ + return zero_copy_if::sptr(new usb_zero_copy_wrapper(usb_zc, usb_frame_boundary)); +} |