[dpdk-dev] [PATCH v15 13/13] doc: Add port hotplug framework section to programmers guide

[Butler, Siobhan A]

> -----Original Message-----
> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Tetsuya Mukawa
> Sent: Wednesday, February 25, 2015 7:32 PM
> To: dev at dpdk.org
> Subject: [dpdk-dev] [PATCH v15 13/13] doc: Add port hotplug framework
> section to programmers guide
> 
> This patch adds a new section for describing port hotplug framework.
> 
> v15:
> - Fix function names like below.
>  - rte_eal_dev_attach() to rte_eth_dev_attach().
>  - rte_eal_dev_detach() to rte_eth_dev_detach().
> 
> Signed-off-by: Tetsuya Mukawa <mukawa at igel.co.jp>
> ---
>  doc/guides/prog_guide/index.rst                  |   1 +
>  doc/guides/prog_guide/port_hotplug_framework.rst | 110
> +++++++++++++++++++++++
>  2 files changed, 111 insertions(+)
>  create mode 100644 doc/guides/prog_guide/port_hotplug_framework.rst
> 
> diff --git a/doc/guides/prog_guide/index.rst
> b/doc/guides/prog_guide/index.rst index de69682..60a6ac5 100644
> --- a/doc/guides/prog_guide/index.rst
> +++ b/doc/guides/prog_guide/index.rst
> @@ -71,6 +71,7 @@ Programmer's Guide
>      packet_classif_access_ctrl
>      packet_framework
>      vhost_lib
> +    port_hotplug_framework
>      source_org
>      dev_kit_build_system
>      dev_kit_root_make_help
> diff --git a/doc/guides/prog_guide/port_hotplug_framework.rst
> b/doc/guides/prog_guide/port_hotplug_framework.rst
> new file mode 100644
> index 0000000..fe6d72a
> --- /dev/null
> +++ b/doc/guides/prog_guide/port_hotplug_framework.rst
> @@ -0,0 +1,110 @@
> +..  BSD LICENSE
> +    Copyright(c) 2015 IGEL Co.,Ltd. All rights reserved.
> +    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 IGEL Co.,Ltd. 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.
> +
> +Port Hotplug Framework
> +======================
> +
> +The Port Hotplug Framework provides DPDK applications with the ability
> +to attach and detach ports at runtime. Because the framework depends on
> +PMD implementation, the ports that PMDs cannot handle are out of scope
> +of this framework. Furthermore, after detaching a port from a DPDK
> +application, the framework doesn't provide a way for removing the devices
> from the system.
> +For the ports backed by a physical NIC, the kernel will need to support
> +PCI Hotplug feature.
> +
> +Overview
> +--------
> +
> +The basic requirements of the Port Hotplug Framework are:
> +
> +*       DPDK applications that use the Port Hotplug Framework must manage
> their
> +        own ports.
> +
> +        The Port Hotplug Framework is implemented to allow DPDK applications
> to
> +        manage ports. For example, when DPDK applications call the port attach
> +        function, the attached port number is returned. DPDK applications can
> +        also detach the port by port number.
> +
> +*       Kernel support is needed for attaching or detaching physical device
> +        ports.
> +
> +        To attach new physical device ports, the device will be recognized by
> +        userspace driver I/O framework in kernel at first. Then DPDK
> +        applications can call the Port Hotplug functions to attach the ports.
> +        For detaching, steps are vice versa.
> +
> +*       Before detaching, they must be stopped and closed.
> +
> +        DPDK applications must call "rte_eth_dev_stop()" and
> +        "rte_eth_dev_close()" APIs before detaching ports. These functions
> will
> +        start finalization sequence of the PMDs.
> +
> +*       The framework doesn't affect legacy DPDK applications behavior.
> +
> +        If the Port Hotplug functions aren't called, all legacy DPDK apps can
> +        still work without modifications.
> +
> +Port Hotplug API overview
> +-------------------------
> +
> +*       Attaching a port
> +
> +        "rte_eth_dev_attach()" API attaches a port to DPDK application, and
> +        returns the attached port number. Before calling the API, the device
> +        should be recognized by an userspace driver I/O framework. The API
> +        receives a pci address like "0000:01:00.0" or a virtual device name
> +        like "eth_pcap0,iface=eth0". In the case of virtual device name, the
> +        format is the same as the general "--vdev" option of DPDK.
> +
> +*       Detaching a port
> +
> +        "rte_eth_dev_detach()" API detaches a port from DPDK application,
> and
> +        returns a pci address of the detached device or a virtual device name
> +        of the device.
> +
> +Reference
> +---------
> +
> +        "testpmd" supports the Port Hotplug Framework.
> +
> +Limitations
> +-----------
> +
> +*       The Port Hotplug APIs are not thread safe.
> +
> +*       The framework can only be enabled with Linux. BSD is not supported.
> +
> +*       To detach a port, the port should be backed by a device that igb_uio
> +        manages. VFIO is not supported.
> +
> +*       Not all PMDs support detaching feature.
> +        To know whether a PMD can support detaching, search for the
> +        "RTE_PCI_DRV_DETACHABLE" flag in PMD implementation. If the flag is
> +        defined in the PMD, detaching is supported.
> --
> 1.9.1
Acked-by: Siobhan Butler <siobhan.a.butler at intel.com>