dpdk: Add new DPDK stack to integrate with I/O services

docs: Update DPDK docs with new parameters:
Parameter names have had their hyphens changed to underscores, and
the I/O CPU argument is now named after the lcores and reflects
the naming used by DPDK.

transport: Add new udp_dpdk_link, based atop the new APIs:
This link is tightly coupled with the DPDK I/O service. The link class
carries all the address information to communicate with the other
host, and it can send packets directly through the DPDK NIC ports.

However, for receiving packets, the I/O service must pull the packets
from the DMA queue and attach them to the appropriate link object.
The link object merely formats the frame_buff object underneath, which
is embedded in the rte_mbuf container. For get_recv_buff, the link
will pull buffers only from its internal queue (the one filled by the
I/O service).

transport: Add DPDK-specific I/O service:
The I/O service is split into two parts, the user threads and the
I/O worker threads. The user threads submit requests through
various appropriate queues, and the I/O threads perform all the
I/O on their behalf. This includes routing UDP packets to the
correct receiver and getting the MAC address of a destination (by
performing the ARP request and handling the ARP replies).

The DPDK context stores I/O services. The context spawns all I/O
services on init(), and I/O services can be fetched from the dpdk_ctx
object by using a port ID.

I/O service clients:
The clients have two lockless ring buffers. One is to get a buffer
from the I/O service; the other is to release a buffer back to the
I/O service. Threads sleeping on buffer I/O are kept in a separate
list from the service queue and are processed in the course of doing
RX or TX.

The list nodes are embedded in the dpdk_io_if, and the head of the
list is on the dpdk_io_service. The I/O service will transfer the
embedded wait_req to the list if it cannot acquire the mutex to
complete the condition for waking.

Co-authored-by: Martin Braun <martin.braun@ettus.com>
Co-authored-by: Ciro Nishiguchi <ciro.nishiguchi@ni.com>
Co-authored-by: Brent Stapleton <brent.stapleton@ettus.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/host/tests/CMakeLists.txt b/host/tests/CMakeLists.txt
index 8e58dd591..2c53e4905 100644
--- a/host/tests/CMakeLists.txt
+++ b/host/tests/CMakeLists.txt
@@ -124,7 +124,10 @@ if(ENABLE_DPDK)
         ${CMAKE_SOURCE_DIR}/lib/utils/paths.cpp
         ${CMAKE_SOURCE_DIR}/lib/utils/pathslib.cpp
         ${CMAKE_SOURCE_DIR}/lib/utils/prefs.cpp
+        ${CMAKE_SOURCE_DIR}/lib/transport/adapter.cpp
         ${CMAKE_SOURCE_DIR}/lib/transport/uhd-dpdk/dpdk_common.cpp
+        ${CMAKE_SOURCE_DIR}/lib/transport/uhd-dpdk/dpdk_io_service.cpp
+        ${CMAKE_SOURCE_DIR}/lib/transport/udp_dpdk_link.cpp
         INCLUDE_DIRS
         ${DPDK_INCLUDE_DIR}
         EXTRA_LIBS ${DPDK_LIBRARIES}
@@ -132,6 +135,8 @@ if(ENABLE_DPDK)
     )
     set_source_files_properties(
         ${CMAKE_SOURCE_DIR}/lib/transport/uhd-dpdk/dpdk_common.cpp
+        ${CMAKE_SOURCE_DIR}/lib/transport/uhd-dpdk/dpdk_io_service.cpp
+        ${CMAKE_SOURCE_DIR}/lib/transport/udp_dpdk_link.cpp
         PROPERTIES COMPILE_FLAGS "-march=native -D_GNU_SOURCE"
     )
 ENDIF(ENABLE_DPDK)