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Diffstat (limited to 'host/lib/include/uhdlib/usrp/common/io_service_mgr.hpp')
-rw-r--r-- | host/lib/include/uhdlib/usrp/common/io_service_mgr.hpp | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/host/lib/include/uhdlib/usrp/common/io_service_mgr.hpp b/host/lib/include/uhdlib/usrp/common/io_service_mgr.hpp new file mode 100644 index 000000000..1093f7bec --- /dev/null +++ b/host/lib/include/uhdlib/usrp/common/io_service_mgr.hpp @@ -0,0 +1,104 @@ +// +// Copyright 2019 Ettus Research, a National Instruments Brand +// +// SPDX-License-Identifier: GPL-3.0-or-later +// + +#ifndef INCLUDED_LIBUHD_IO_SERVICE_MGR_HPP +#define INCLUDED_LIBUHD_IO_SERVICE_MGR_HPP + +#include <uhd/transport/adapter_id.hpp> +#include <uhd/types/device_addr.hpp> +#include <uhdlib/transport/io_service.hpp> +#include <uhdlib/transport/link_if.hpp> +#include <uhdlib/transport/links.hpp> +#include <uhdlib/usrp/common/io_service_args.hpp> +#include <memory> + +namespace uhd { namespace usrp { + +/*! Class to create and manage I/O services + * + * The I/O service manager connects links to I/O services, instantiating new I/O + * services as needed. It chooses the I/O service to connect based on options + * from the user passed through stream_args, as well as defaults provided by the + * caller. + * + * The I/O service manager supports two types of I/O services: inline I/O service + * and offload I/O service. Inline I/O services execute all I/O in the caller + * thread. Offload I/O services execute all I/O in an offload thread. The offload + * thread can be configured to block or poll. All control links use inline I/O + * services, only RX and TX data links currently use offload I/O services. + * + * If polling I/O services are requested, the I/O service manager instantiates + * the number of I/O services specified by the user through args. It chooses + * which I/O service to connect a set of links to by selecting the I/O service + * with the fewest number of connections. + * + * If blocking I/O services are requested, the I/O service manager instantiates + * one offload I/O service for each transport adapter used by a streamer. When + * there are multiple streamers, this manager creates a separate set of I/O + * services for each streamer. + * + * Offload I/O services have a number of restrictions that must be observed: + * - Offload I/O services currently do not support links that require frame + * buffers to be released in order. + * - Blocking I/O services should only be used for groups of RX or TX data + * transport in the same streamer. Since the I/O service blocks on each + * channel, if two streamers were to be configured to share the I/O service, + * one streamer would block the progress of the other. The I/O service + * manager ensures this restriction is observed by grouping I/O services + * and links appropriately. + * - Blocking I/O services do not currently support muxed links, since the I/O + * service is specialized to either RX or TX data and the procedure to configure + * a data transport requires both RX and TX clients. The I/O service manager + * throws an exception if requested to mux a link configured with a blocking + * I/O service. + */ +class io_service_mgr +{ +public: + using sptr = std::shared_ptr<io_service_mgr>; + + /*! Connects a pair of links to an I/O service + * + * Call this method to connect a pair of links to an I/O service. For muxed + * links, the I/O service manager keeps track of the number of muxed + * connections (the number of times this method has been called with the same + * links). + * + * The last two parameters are ignored for control links. + * + * \param recv_link The recv link to connect to an I/O service + * \param send_link The send link to connect to an I/O service + * \param link_type The type of transport in which the links will be used + * \param io_srv_args The user-requested options for the stream + * \param streamer_id A unique ID for the streamer that will use the links + * \return The I/O service to which the links are connected + */ + virtual transport::io_service::sptr connect_links( + transport::recv_link_if::sptr recv_link, + transport::send_link_if::sptr send_link, + const transport::link_type_t link_type, + const io_service_args_t& io_srv_args = io_service_args_t(), + const std::string& streamer_id = "") = 0; + + /*! Disconnects links from their I/O service + * + * \param recv_link The recv link to disconnect from an I/O service + * \param send_link The send link to disconnect from an I/O service + */ + virtual void disconnect_links(transport::recv_link_if::sptr recv_link, + transport::send_link_if::sptr send_link) = 0; + + /*! Creates an instance of an I/O service manager + * + * \params Device args used to create the UHD session + * \return The I/O service manager instance + */ + static sptr make(const uhd::device_addr_t& args); +}; + +}} // namespace uhd::usrp + +#endif /* INCLUDED_LIBUHD_IO_SERVICE_MGR_HPP */ |