Re: [dpdk-dev] [PATCH v2 1/8] ether: refine debug compile option

["Zhang, Qi Z" <qi.z.zhang@intel.com>]

> -----Original Message-----
> From: Yigit, Ferruh <ferruh.yigit@intel.com>
> Sent: Tuesday, March 23, 2021 1:24 AM
> To: Thomas Monjalon <thomas@monjalon.net>; Zhang, Qi Z
> <qi.z.zhang@intel.com>; Andrew Rybchenko <arybchenko@solarflare.com>
> Cc: dev@dpdk.org; Wang, Xiao W <xiao.w.wang@intel.com>; Wu, Jingjing
> <jingjing.wu@intel.com>; Xing, Beilei <beilei.xing@intel.com>; Guo, Jia
> <jia.guo@intel.com>; Yang, Qiming <qiming.yang@intel.com>; Wang, Haiyue
> <haiyue.wang@intel.com>; Richardson, Bruce <bruce.richardson@intel.com>
> Subject: Re: [dpdk-dev] [PATCH v2 1/8] ether: refine debug compile option
> 
> On 3/16/2021 4:37 PM, Ferruh Yigit wrote:
> > On 3/16/2021 1:39 PM, Thomas Monjalon wrote:
> >> 16/03/2021 14:05, Ferruh Yigit:
> >>> On 3/12/2021 12:12 PM, Qi Zhang wrote:
> >>>> PMDs use RTE_LIBRTE_<PMD_NAME>_DEBUG_RX|TX as compile option
> to
> >>>> wrap data path debug code. As .config has been removed since the
> >>>> meson build, It is not friendly for new DPDK users to notice those debug
> options.
> >>>>
> >>>> The patch introduces below compile options for specific Rx/Tx data
> >>>> path debug, so PMD can choose to reuse them to avoid maintain their
> own.
> >>>>
> >>>> - RTE_LIBRTE_ETHDEV_DEBUG_RX
> >>>> - RTE_LIBRTE_ETHDEV_DEBUG_TX
> >>>>
> >>>> Also, all the compile options are documented on the overview page,
> >>>> so users can easily find them.
> >
> > <...>
> >
> >>>> +
> >>>> +- ``RTE_LIBRTE_ETHDEV_DEBUG`` (default **disabled**)
> >>>> +
> >>>> +  Compile with debug code on data path.
> >>
> >> What is data path if not Rx or Tx?
> >>
> >>>> +
> >>>> +- ``RTE_LIBRTE_ETHDEV_DEBUG_RX`` (default **disabled**)
> >>>> +
> >>>> +  Compile with debug code on Rx data path.
> >>>> +
> >>>> +- ``RTE_LIBRTE_ETHDEV_DEBUG_TX`` (default **disabled**)
> >>>> +
> >>>> +  Compile with debug code on Tx data path.
> >>
> >> In general, I think "LIBRTE_" is redundant and useless as macro prefix.
> >>
> >
> >
> > 'RTE_LIBRTE_ETHDEV_DEBUG' already exits, it enables datapath debug
> > without distinguishing Rx or Tx.
> >
> > When we have _RX and _TX macro variants now, it may be possible to
> > 1- get rid of 'RTE_LIBRTE_ETHDEV_DEBUG' macro and continue with fine
> > grained RX & TX
> > 2- Use 'RTE_LIBRTE_ETHDEV_DEBUG' as an alias to enable both RX & TX
> > 3- Keep 'RTE_LIBRTE_ETHDEV_DEBUG' for ethdev layer datapath debug, and
> > RX & TX variants for PMDs.
> >
> > I think (3) can be more backward compatible, and can be helpful to
> > separate ethdev layer and PMD debugging, but no so strong opinion.
> 
> Hi Qi,
> 
> Reminder of above discussion, it is not addressed in v4. What do you think
> option 3 above?

As discussed with Ferruh, we are agree to take option 1), which means

1. RTE_ETHDEV_DEBUG will be removed, as user can use to use _RX, _TX directly.

2. Now alias RTE_LIBRTE_ETHDEV_DEBUG to RTE_ETHDEV_RX and RTE_ETHDEV_TX for backward compatibility.

3. we will not take option 2, because, is may cause different behavior when rte_ethdev.h is included a PMD source file or not.

I will send V5 base on it, and let 's continued the discussion base on that if more inputs.

Thanks
Qi