diff options
| -rw-r--r-- | host/lib/usrp/usrp1/io_impl.cpp | 169 | ||||
| -rw-r--r-- | host/lib/usrp/usrp1/usrp1_impl.hpp | 10 |
2 files changed, 99 insertions, 80 deletions
diff --git a/host/lib/usrp/usrp1/io_impl.cpp b/host/lib/usrp/usrp1/io_impl.cpp index 676b1536a..0a16f7a43 100644 --- a/host/lib/usrp/usrp1/io_impl.cpp +++ b/host/lib/usrp/usrp1/io_impl.cpp @@ -33,6 +33,28 @@ using namespace uhd::usrp; using namespace uhd::transport; namespace asio = boost::asio; +static const size_t alignment_padding = 512; + +/*********************************************************************** + * Helper struct to associate an offset with a buffer + **********************************************************************/ +class offset_send_buffer{ +public: + typedef boost::shared_ptr<offset_send_buffer> sptr; + + static sptr make(managed_send_buffer::sptr buff, size_t offset = 0){ + return sptr(new offset_send_buffer(buff, offset)); + } + + //member variables + managed_send_buffer::sptr buff; + size_t offset; /* in bytes */ + +private: + offset_send_buffer(managed_send_buffer::sptr buff, size_t offset): + buff(buff), offset(offset){/* NOP */} +}; + /*********************************************************************** * IO Implementation Details **********************************************************************/ @@ -41,8 +63,7 @@ struct usrp1_impl::io_impl{ data_transport(data_transport), underflow_poll_samp_count(0), overflow_poll_samp_count(0), - send_buff(data_transport->get_send_buff()), - num_bytes_committed(0) + curr_buff(offset_send_buffer::make(data_transport->get_send_buff())) { /* NOP */ } @@ -62,98 +83,88 @@ struct usrp1_impl::io_impl{ size_t overflow_poll_samp_count; //wrapper around the actual send buffer interface - //all of this to ensure only full buffers are committed - managed_send_buffer::sptr send_buff; - size_t num_bytes_committed; - double send_timeout; - boost::uint8_t pseudo_buff[BYTES_PER_PACKET]; - void phony_commit_pseudo_buff(size_t num_bytes); - void phony_commit_send_buff(size_t num_bytes); - void commit_send_buff(void); + //all of this to ensure only aligned lengths are committed + //NOTE: you must commit before getting a new buffer + //since the vrt packet handler obeys this, we are ok + offset_send_buffer::sptr curr_buff; + void commit_send_buff(offset_send_buffer::sptr, offset_send_buffer::sptr, size_t); void flush_send_buff(void); bool get_send_buffs(vrt_packet_handler::managed_send_buffs_t &, double); - - //helpers to get at the send buffer + offset - inline void *get_send_mem_ptr(void){ - return send_buff->cast<boost::uint8_t *>() + num_bytes_committed; - } - inline size_t get_send_mem_size(void){ - return send_buff->size() - num_bytes_committed; - } }; /*! - * Accept a commit of num bytes to the pseudo buffer. - * Memcpy the entire contents of pseudo buffer into send buffers. - * - * Under most conditions: - * The first loop iteration will fill the remainder of the send buffer. - * The second loop iteration will empty the pseudo buffer remainder. + * Perform an actual commit on the send buffer: + * Copy the remainder of alignment to the next buffer. + * Commit the current buffer at multiples of alignment. */ -void usrp1_impl::io_impl::phony_commit_pseudo_buff(size_t num_bytes){ - size_t bytes_to_copy = num_bytes, bytes_copied = 0; - while(bytes_to_copy){ - size_t bytes_copied_here = std::min(bytes_to_copy, get_send_mem_size()); - std::memcpy(get_send_mem_ptr(), pseudo_buff + bytes_copied, bytes_copied_here); - phony_commit_send_buff(bytes_copied_here); - bytes_to_copy -= bytes_copied_here; - bytes_copied += bytes_copied_here; - } -} +void usrp1_impl::io_impl::commit_send_buff( + offset_send_buffer::sptr curr, + offset_send_buffer::sptr next, + size_t num_bytes +){ + //total number of bytes now in the current buffer + size_t bytes_in_curr_buffer = curr->offset + num_bytes; -/*! - * Accept a commit of num bytes to the send buffer. - * Conditionally commit the send buffer if full. - */ -void usrp1_impl::io_impl::phony_commit_send_buff(size_t num_bytes){ - num_bytes_committed += num_bytes; - if (num_bytes_committed != send_buff->size()) return; - commit_send_buff(); + //calculate how many to commit and remainder + size_t num_bytes_remaining = bytes_in_curr_buffer % alignment_padding; + size_t num_bytes_to_commit = bytes_in_curr_buffer - num_bytes_remaining; + + //copy the remainder into the next buffer + std::memcpy( + next->buff->cast<char *>() + next->offset, + curr->buff->cast<char *>() + num_bytes_to_commit, + num_bytes_remaining + ); + + //update the offset into the next buffer + next->offset += num_bytes_remaining; + + //commit the current buffer + curr->buff->commit(num_bytes_to_commit); } /*! - * Flush the send buffer: - * Zero-pad the send buffer to the nearest 512 byte boundary and commit. + * Flush the current buffer by padding out to alignment and committing. */ void usrp1_impl::io_impl::flush_send_buff(void){ - size_t bytes_to_pad = (-1*num_bytes_committed)%512; - std::memset(get_send_mem_ptr(), 0, bytes_to_pad); - num_bytes_committed += bytes_to_pad; - commit_send_buff(); + //calculate the number of bytes to alignment + size_t bytes_to_pad = (-1*curr_buff->offset)%alignment_padding; + + //get the buffer, clear, and commit (really current buffer) + vrt_packet_handler::managed_send_buffs_t buffs(1); + if (this->get_send_buffs(buffs, 0.1)){ + std::memset(buffs[0]->cast<void *>(), 0, bytes_to_pad); + buffs[0]->commit(bytes_to_pad); + } } /*! - * Perform an actual commit on the send buffer: - * Commit the contents of the send buffer and request a new buffer. + * Get a managed send buffer with the alignment padding: + * Always grab the next send buffer so we can timeout here. */ -void usrp1_impl::io_impl::commit_send_buff(void){ - send_buff->commit(num_bytes_committed); - send_buff = data_transport->get_send_buff(send_timeout); - num_bytes_committed = 0; -} - bool usrp1_impl::io_impl::get_send_buffs( vrt_packet_handler::managed_send_buffs_t &buffs, double timeout ){ - send_timeout = timeout; UHD_ASSERT_THROW(buffs.size() == 1); - //not enough bytes free -> use the pseudo buffer - if (get_send_mem_size() < BYTES_PER_PACKET){ - buffs[0] = managed_send_buffer::make_safe( - boost::asio::buffer(pseudo_buff), - boost::bind(&usrp1_impl::io_impl::phony_commit_pseudo_buff, this, _1) - ); - } - //otherwise use the send buffer offset by the bytes written - else{ - buffs[0] = managed_send_buffer::make_safe( - boost::asio::buffer(get_send_mem_ptr(), get_send_mem_size()), - boost::bind(&usrp1_impl::io_impl::phony_commit_send_buff, this, _1) - ); - } + //try to get a new managed buffer with timeout + offset_send_buffer::sptr next_buff(offset_send_buffer::make(data_transport->get_send_buff(timeout))); + if (not next_buff->buff.get()) return false; /* propagate timeout here */ - return buffs[0].get() != NULL; + //calculate the buffer pointer and size given the offset + //references to the buffers are held in the bound function + buffs[0] = managed_send_buffer::make_safe( + boost::asio::buffer( + curr_buff->buff->cast<char *>() + curr_buff->offset, + curr_buff->buff->size() - curr_buff->offset + ), + boost::bind(&usrp1_impl::io_impl::commit_send_buff, this, curr_buff, next_buff, _1) + ); + + //store the next buffer for the next call + curr_buff = next_buff; + + return true; } /*********************************************************************** @@ -182,6 +193,13 @@ static void usrp1_bs_vrt_packer( if_packet_info.num_packet_words32 = if_packet_info.num_payload_words32; } +size_t usrp1_impl::get_max_send_samps_per_packet(void) const { + return (_data_transport->get_send_frame_size() - alignment_padding) + / _tx_otw_type.get_sample_size() + / _tx_subdev_spec.size() + ; +} + size_t usrp1_impl::send( const std::vector<const void *> &buffs, size_t num_samps, const tx_metadata_t &metadata, const io_type_t &io_type, @@ -249,6 +267,13 @@ static bool get_recv_buffs( return buffs[0].get() != NULL; } +size_t usrp1_impl::get_max_recv_samps_per_packet(void) const { + return _data_transport->get_recv_frame_size() + / _rx_otw_type.get_sample_size() + / _rx_subdev_spec.size() + ; +} + size_t usrp1_impl::recv( const std::vector<void *> &buffs, size_t num_samps, rx_metadata_t &metadata, const io_type_t &io_type, diff --git a/host/lib/usrp/usrp1/usrp1_impl.hpp b/host/lib/usrp/usrp1/usrp1_impl.hpp index f2c464610..ff4d40762 100644 --- a/host/lib/usrp/usrp1/usrp1_impl.hpp +++ b/host/lib/usrp/usrp1/usrp1_impl.hpp @@ -90,15 +90,9 @@ public: const uhd::io_type_t &, recv_mode_t, double); - static const size_t BYTES_PER_PACKET = 512*4; //under the transfer size + size_t get_max_send_samps_per_packet(void) const; - size_t get_max_send_samps_per_packet(void) const { - return BYTES_PER_PACKET/_tx_otw_type.get_sample_size()/_tx_subdev_spec.size(); - } - - size_t get_max_recv_samps_per_packet(void) const { - return BYTES_PER_PACKET/_rx_otw_type.get_sample_size()/_rx_subdev_spec.size(); - } + size_t get_max_recv_samps_per_packet(void) const; bool recv_async_msg(uhd::async_metadata_t &, double); |