X-Git-Url: http://git.droids-corp.org/?a=blobdiff_plain;f=doc%2Fguides%2Fvdpadevs%2Fmlx5.rst;h=9b2f9f12c7c65fefd2020412016cbd12e2712e4f;hb=fc5bffb8b5ba17c110b8c3c35c6090e3345ad000;hp=2c7a550afcd24dff66a80ede1c32f3634921699c;hpb=251691f107a565807be613439a431a6072edba15;p=dpdk.git diff --git a/doc/guides/vdpadevs/mlx5.rst b/doc/guides/vdpadevs/mlx5.rst index 2c7a550afc..9b2f9f12c7 100644 --- a/doc/guides/vdpadevs/mlx5.rst +++ b/doc/guides/vdpadevs/mlx5.rst @@ -7,16 +7,14 @@ MLX5 vDPA driver ================ The MLX5 vDPA (vhost data path acceleration) driver library -(**librte_pmd_mlx5_vdpa**) provides support for **Mellanox ConnectX-6**, +(**librte_vdpa_mlx5**) provides support for **Mellanox ConnectX-6**, **Mellanox ConnectX-6 Dx** and **Mellanox BlueField** families of 10/25/40/50/100/200 Gb/s adapters as well as their virtual functions (VF) in SR-IOV context. .. note:: - Due to external dependencies, this driver is disabled in default - configuration of the "make" build. It can be enabled with - ``CONFIG_RTE_LIBRTE_MLX5_VDPA_PMD=y`` or by using "meson" build system which + This driver is enabled automatically when using "meson" build system which will detect dependencies. @@ -39,7 +37,7 @@ to get the best performances: - DevX allows to access firmware objects - Direct Rules manages flow steering at low-level hardware layer -Enabling librte_pmd_mlx5_vdpa causes DPDK applications to be linked against +Enabling librte_vdpa_mlx5 causes DPDK applications to be linked against libibverbs. A Mellanox mlx5 PCI device can be probed by either net/mlx5 driver or vdpa/mlx5 @@ -62,16 +60,13 @@ Prerequisites - Mellanox OFED version: **5.0** see :doc:`../../nics/mlx5` guide for more Mellanox OFED details. -Compilation options -~~~~~~~~~~~~~~~~~~~ +Compilation option +~~~~~~~~~~~~~~~~~~ -These options can be modified in the ``.config`` file. +The meson option ``ibverbs_link`` is **shared** by default, +but can be configured to have the following values: -- ``CONFIG_RTE_LIBRTE_MLX5_VDPA_PMD`` (default **n**) - - Toggle compilation of librte_pmd_mlx5 itself. - -- ``CONFIG_RTE_IBVERBS_LINK_DLOPEN`` (default **n**) +- ``dlopen`` Build PMD with additional code to make it loadable without hard dependencies on **libibverbs** nor **libmlx5**, which may not be installed @@ -79,28 +74,23 @@ These options can be modified in the ``.config`` file. In this mode, their presence is still required for it to run properly, however their absence won't prevent a DPDK application from starting (with - ``CONFIG_RTE_BUILD_SHARED_LIB`` disabled) and they won't show up as - missing with ``ldd(1)``. + DPDK shared build disabled) and they won't show up as missing with ``ldd(1)``. It works by moving these dependencies to a purpose-built rdma-core "glue" - plug-in which must either be installed in a directory whose name is based - on ``CONFIG_RTE_EAL_PMD_PATH`` suffixed with ``-glue`` if set, or in a - standard location for the dynamic linker (e.g. ``/lib``) if left to the - default empty string (``""``). + plug-in which must be installed in a directory whose name is based + on ``RTE_EAL_PMD_PATH`` suffixed with ``-glue``. This option has no performance impact. -- ``CONFIG_RTE_IBVERBS_LINK_STATIC`` (default **n**) +- ``static`` Embed static flavor of the dependencies **libibverbs** and **libmlx5** in the PMD shared library or the executable static binary. .. note:: - For BlueField, target should be set to ``arm64-bluefield-linux-gcc``. This - will enable ``CONFIG_RTE_LIBRTE_MLX5_VDPA_PMD`` and set - ``RTE_CACHE_LINE_SIZE`` to 64. Default armv8a configuration of make build and - meson build set it to 128 then brings performance degradation. + Default armv8a configuration of meson build sets ``RTE_CACHE_LINE_SIZE`` + to 128 then brings performance degradation. Run-time configuration ~~~~~~~~~~~~~~~~~~~~~~ @@ -126,7 +116,7 @@ Driver options - 2, Completion queue scheduling will be managed by interrupts. Each CQ burst arms the CQ in order to get an interrupt event in the next traffic burst. - - Default mode is 0. + - Default mode is 1. - ``event_us`` parameter [int] @@ -135,12 +125,48 @@ Driver options - 0, A nonzero value to set timer step in micro-seconds. The timer thread dynamic delay change steps according to this value. Default value is 1us. - - 1, A nonzero value to set fixed timer delay in micro-seconds. Default value - is 100us. + - 1, A value to set fixed timer delay in micro-seconds. Default value is 0us. - ``no_traffic_time`` parameter [int] - A nonzero value defines the traffic off time, in seconds, that moves the - driver to no-traffic mode. In this mode the timer events are stopped and - interrupts are configured to the device in order to notify traffic for the - driver. Default value is 2s. + A nonzero value defines the traffic off time, in polling cycle time units, + that moves the driver to no-traffic mode. In this mode the polling is stopped + and interrupts are configured to the device in order to notify traffic for the + driver. Default value is 16. + +- ``event_core`` parameter [int] + + CPU core number to set polling thread affinity to, default to control plane + cpu. + +- ``hw_latency_mode`` parameter [int] + + The completion queue moderation mode: + + - 0, HW default. + + - 1, Latency is counted from the first packet completion report. + + - 2, Latency is counted from the last packet completion. + +- ``hw_max_latency_us`` parameter [int] + + - 1 - 4095, The maximum time in microseconds that packet completion report + can be delayed. + + - 0, HW default. + +- ``hw_max_pending_comp`` parameter [int] + + - 1 - 65535, The maximum number of pending packets completions in an HW queue. + + - 0, HW default. + + +Error handling +^^^^^^^^^^^^^^ + +Upon potential hardware errors, mlx5 PMD try to recover, give up if failed 3 +times in 3 seconds, virtq will be put in disable state. User should check log +to get error information, or query vdpa statistics counter to know error type +and count report.