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authorChristian Ehrhardt <christian.ehrhardt@canonical.com>2017-05-16 14:51:32 +0200
committerChristian Ehrhardt <christian.ehrhardt@canonical.com>2017-05-16 16:20:45 +0200
commit7595afa4d30097c1177b69257118d8ad89a539be (patch)
tree4bfeadc905c977e45e54a90c42330553b8942e4e /doc/guides/eventdevs
parentce3d555e43e3795b5d9507fcfc76b7a0a92fd0d6 (diff)
Imported Upstream version 17.05
Change-Id: Id1e419c5a214e4a18739663b91f0f9a549f1fdc6 Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
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+.. BSD LICENSE
+ Copyright(c) 2017 Intel Corporation. All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
+
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+ * Neither the name of Intel Corporation nor the names of its
+ contributors may be used to endorse or promote products derived
+ from this software without specific prior written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+Event Device Drivers
+====================
+
+The following are a list of event device PMDs, which can be used from an
+application trough the eventdev API.
+
+.. toctree::
+ :maxdepth: 2
+ :numbered:
+
+ sw
+ octeontx
diff --git a/doc/guides/eventdevs/octeontx.rst b/doc/guides/eventdevs/octeontx.rst
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+.. BSD LICENSE
+ Copyright (C) Cavium networks Ltd. 2017.
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
+
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+ * Neither the name of Cavium networks nor the names of its
+ contributors may be used to endorse or promote products derived
+ from this software without specific prior written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+OCTEONTX SSOVF Eventdev Driver
+==============================
+
+The OCTEONTX SSOVF PMD (**librte_pmd_octeontx_ssovf**) provides poll mode
+eventdev driver support for the inbuilt event device found in the **Cavium OCTEONTX**
+SoC family as well as their virtual functions (VF) in SR-IOV context.
+
+More information can be found at `Cavium Networks Official Website
+<http://www.cavium.com/OCTEON-TX_ARM_Processors.html>`_.
+
+Features
+--------
+
+Features of the OCTEONTX SSOVF PMD are:
+
+- 64 Event queues
+- 32 Event ports
+- HW event scheduler
+- Supports 1M flows per event queue
+- Flow based event pipelining
+- Flow pinning support in flow based event pipelining
+- Queue based event pipelining
+- Supports ATOMIC, ORDERED, PARALLEL schedule types per flow
+- Event scheduling QoS based on event queue priority
+- Open system with configurable amount of outstanding events
+- HW accelerated dequeue timeout support to enable power management
+- SR-IOV VF
+
+Supported OCTEONTX SoCs
+-----------------------
+- CN83xx
+
+Prerequisites
+-------------
+
+There are three main pre-perquisites for executing SSOVF PMD on a OCTEONTX
+compatible board:
+
+1. **OCTEONTX Linux kernel PF driver for Network acceleration HW blocks**
+
+ The OCTEONTX Linux kernel drivers (including the required PF driver for the
+ SSOVF) are available on Github at `octeontx-kmod <https://github.com/caviumnetworks/octeontx-kmod>`_
+ along with build, install and dpdk usage instructions.
+
+2. **ARM64 Tool Chain**
+
+ For example, the *aarch64* Linaro Toolchain, which can be obtained from
+ `here <https://releases.linaro.org/components/toolchain/binaries/4.9-2017.01/aarch64-linux-gnu>`_.
+
+3. **Rootfile system**
+
+ Any *aarch64* supporting filesystem can be used. For example,
+ Ubuntu 15.10 (Wily) or 16.04 LTS (Xenial) userland which can be obtained
+ from `<http://cdimage.ubuntu.com/ubuntu-base/releases/16.04/release/ubuntu-base-16.04.1-base-arm64.tar.gz>`_.
+
+ As an alternative method, SSOVF PMD can also be executed using images provided
+ as part of SDK from Cavium. The SDK includes all the above prerequisites necessary
+ to bring up a OCTEONTX board.
+
+ SDK and related information can be obtained from: `Cavium support site <https://support.cavium.com/>`_.
+
+- Follow the DPDK :ref:`Getting Started Guide for Linux <linux_gsg>` to setup the basic DPDK environment.
+
+Pre-Installation Configuration
+------------------------------
+
+Config File Options
+~~~~~~~~~~~~~~~~~~~
+
+The following options can be modified in the ``config`` file.
+Please note that enabling debugging options may affect system performance.
+
+- ``CONFIG_RTE_LIBRTE_PMD_OCTEONTX_SSOVF`` (default ``y``)
+
+ Toggle compilation of the ``librte_pmd_octeontx_ssovf`` driver.
+
+- ``CONFIG_RTE_LIBRTE_PMD_OCTEONTX_SSOVF_DEBUG`` (default ``n``)
+
+ Toggle display of generic debugging messages
+
+Driver Compilation
+~~~~~~~~~~~~~~~~~~
+
+To compile the OCTEONTX SSOVF PMD for Linux arm64 gcc target, run the
+following ``make`` command:
+
+.. code-block:: console
+
+ cd <DPDK-source-directory>
+ make config T=arm64-thunderx-linuxapp-gcc install
+
+
+Initialization
+--------------
+
+The octeontx eventdev is exposed as a vdev device which consists of a set
+of SSO group and work-slot PCIe VF devices. On EAL initialization,
+SSO PCIe VF devices will be probed and then the vdev device can be created
+from the application code, or from the EAL command line based on
+the number of probed/bound SSO PCIe VF device to DPDK by
+
+* Invoking ``rte_vdev_init("event_octeontx")`` from the application
+
+* Using ``--vdev="event_octeontx"`` in the EAL options, which will call
+ rte_vdev_init() internally
+
+Example:
+
+.. code-block:: console
+
+ ./your_eventdev_application --vdev="event_octeontx"
+
+Limitations
+-----------
+
+Burst mode support
+~~~~~~~~~~~~~~~~~~
+
+Burst mode is not supported. Dequeue and Enqueue functions accepts only single
+event at a time.
+
diff --git a/doc/guides/eventdevs/sw.rst b/doc/guides/eventdevs/sw.rst
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+.. BSD LICENSE
+ Copyright(c) 2017 Intel Corporation. All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
+
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+ * Neither the name of Intel Corporation nor the names of its
+ contributors may be used to endorse or promote products derived
+ from this software without specific prior written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+Software Eventdev Poll Mode Driver
+==================================
+
+The software eventdev is an implementation of the eventdev API, that provides a
+wide range of the eventdev features. The eventdev relies on a CPU core to
+perform event scheduling.
+
+
+Features
+--------
+
+The software eventdev implements many features in the eventdev API;
+
+Queues
+ * Atomic
+ * Ordered
+ * Parallel
+ * Single-Link
+
+Ports
+ * Load balanced (for Atomic, Ordered, Parallel queues)
+ * Single Link (for single-link queues)
+
+Event Priorities
+ * Each event has a priority, which can be used to provide basic QoS
+
+
+Configuration and Options
+-------------------------
+
+The software eventdev is a vdev device, and as such can be created from the
+application code, or from the EAL command line:
+
+* Call ``rte_vdev_init("event_sw0")`` from the application
+
+* Use ``--vdev="event_sw0"`` in the EAL options, which will call
+ rte_vdev_init() internally
+
+Example:
+
+.. code-block:: console
+
+ ./your_eventdev_application --vdev="event_sw0"
+
+
+Scheduling Quanta
+~~~~~~~~~~~~~~~~~
+
+The scheduling quanta sets the number of events that the device attempts to
+schedule before returning to the application from the ``rte_event_schedule()``
+function. Note that is a *hint* only, and that fewer or more events may be
+scheduled in a given iteration.
+
+The scheduling quanta can be set using a string argument to the vdev
+create call:
+
+.. code-block:: console
+
+ --vdev="event_sw0,sched_quanta=64"
+
+
+Credit Quanta
+~~~~~~~~~~~~~
+
+The credit quanta is the number of credits that a port will fetch at a time from
+the instance's credit pool. Higher numbers will cause less overhead in the
+atomic credit fetch code, however it also reduces the overall number of credits
+in the system faster. A balanced number (eg 32) ensures that only small numbers
+of credits are pre-allocated at a time, while also mitigating performance impact
+of the atomics.
+
+Experimentation with higher values may provide minor performance improvements,
+at the cost of the whole system having less credits. On the other hand,
+reducing the quanta may cause measurable performance impact but provide the
+system with a higher number of credits at all times.
+
+A value of 32 seems a good balance however your specific application may
+benefit from a higher or reduced quanta size, experimentation is required to
+verify possible gains.
+
+.. code-block:: console
+
+ --vdev="event_sw0,credit_quanta=64"
+
+
+Limitations
+-----------
+
+The software eventdev implementation has a few limitations. The reason for
+these limitations is usually that the performance impact of supporting the
+feature would be significant.
+
+
+"All Types" Queues
+~~~~~~~~~~~~~~~~~~
+
+The software eventdev does not support creating queues that handle all types of
+traffic. An eventdev with this capability allows enqueueing Atomic, Ordered and
+Parallel traffic to the same queue, but scheduling each of them appropriately.
+
+The reason to not allow Atomic, Ordered and Parallel event types in the
+same queue is that it causes excessive branching in the code to enqueue packets
+to the queue, causing a significant performance impact.
+
+The ``RTE_EVENT_DEV_CAP_QUEUE_ALL_TYPES`` flag is not set in the
+``event_dev_cap`` field of the ``rte_event_dev_info`` struct for the software
+eventdev.
+
+Distributed Scheduler
+~~~~~~~~~~~~~~~~~~~~~
+
+The software eventdev is a centralized scheduler, requiring the
+``rte_event_schedule()`` function to be called by a CPU core to perform the
+required event distribution. This is not really a limitation but rather a
+design decision.
+
+The ``RTE_EVENT_DEV_CAP_DISTRIBUTED_SCHED`` flag is not set in the
+``event_dev_cap`` field of the ``rte_event_dev_info`` struct for the software
+eventdev.
+
+Dequeue Timeout
+~~~~~~~~~~~~~~~
+
+The eventdev API supports a timeout when dequeuing packets using the
+``rte_event_dequeue_burst`` function.
+This allows a core to wait for an event to arrive, or until ``timeout`` number
+of ticks have passed. Timeout ticks is not supported by the software eventdev
+for performance reasons.