Re: [dpdk-dev] 答复: Port-ids and NIC features

[Stephen Hemminger <stephen@networkplumber.org>]

On Thu, 15 Aug 2013 09:51:00 +0800
安宏奎 <anhk_@126.com> wrote:

> For the question one, maybe you can detect it before binding to igb_uio
> 
> 
> -----邮件原件-----
> 发件人: dev-bounces@dpdk.org [mailto:dev-bounces@dpdk.org] 代表 Marc Sune
> 发送时间: 2013年8月14日 16:57
> 收件人: dev@dpdk.org
> 主题: [dpdk-dev] Port-ids and NIC features
> 
> Dear all,
> 
> Two quick questions:
> 
> 1) Is there a way to get the features available in the NIC? In particular, I
> cannot see a way to retrieve the *maximum speed* of the card and I need to
> determine whether is a FE, GE or 10GE card.

Not at present. You need to look at the information in rte_pci_device
for the ethernet (see rte_eth_dev_info) and then do your own matching
against ID and features.

As DPDK evolves more of the hardware features need to be abstracted
to allow applications to be build once and run on varying hardware.
IMHO some of the low level features like read/write thresholds really
shouldn't be exposed through the API. Setting them correctly depends
too much on the underlying hardware, chip version, and driver and really
shouldn't be something the application writer has to worry about.


> 2) For a certain number of NICs installed in the system and bound to the
> IGB_UIO driver, is it safe to assume that the association phyisical port <->
> port_id will always be the same? Even after reboot, and regardless of the
> order that are bound to the IGB_UIO driver (e.g. using pci_unbind.py)?

Since probe is single threaded. The discovery order will be constant
on the same system. But will change if hardware added/removed.

Another future area of work that needs to be addressed is hot plugging
devices into a running application.