RE: [PATCH] net/gve: add support for basic stats

["Guo, Junfeng" <junfeng.guo@intel.com>]

> -----Original Message-----
> From: Stephen Hemminger <stephen@networkplumber.org>
> Sent: Tuesday, November 29, 2022 01:24
> To: Ferruh Yigit <ferruh.yigit@amd.com>
> Cc: Rushil Gupta <rushilg@google.com>; Guo, Junfeng
> <junfeng.guo@intel.com>; Zhang, Qi Z <qi.z.zhang@intel.com>; Wu,
> Jingjing <jingjing.wu@intel.com>; Xing, Beilei <beilei.xing@intel.com>;
> dev@dpdk.org; jeroendb@google.com; jrkim@google.com; Li, Xiaoyun
> <xiaoyun.li@intel.com>
> Subject: Re: [PATCH] net/gve: add support for basic stats
> 
> On Mon, 28 Nov 2022 11:12:38 +0000
> Ferruh Yigit <ferruh.yigit@amd.com> wrote:
> 
> > On 11/26/2022 5:34 PM, Stephen Hemminger wrote:
> > > On Fri, 25 Nov 2022 19:16:00 -0800
> > > Rushil Gupta <rushilg@google.com> wrote:
> > >
> > >>>>
> > >>>> The driver should be filling in the per-queue stats as well.
> > >>>> q_ipackets, q_opackets, q_ibytes, q_obytes, q_errors
> > >>>
> > >>>
> > >>> Hi Stephen,
> > >>>
> > >>> Queue stats moved to xstats, and there is a long term goal to move
> all
> > >>> queue stats from basic stats to xstats for all PMDs, and remove
> interim
> > >>> 'RTE_ETH_DEV_AUTOFILL_QUEUE_XSTATS' flag.
> > >>>
> > >>> That is why request to new PMDs is to not introduce queue stats in
> basic
> > >>> stats, but in xstats.
> > >
> > > Agree that xstats are better but:
> > >
> > > * the current checked in version of GVE does not have driver op for
> xstats
> > >
> > > * if driver fills in the q_XXX[] stats then eth_dev_get_xstats_basic will
> be
> > >   able to use it.
> > >
> >
> > That is an option, but it will require driver to add
> > 'RTE_ETH_DEV_AUTOFILL_QUEUE_XSTATS' flag what we want to get
> rid of in
> > long term.
> > That is why we are requesting new driver to add the xstats
> > implementation instead of adding queue support in basic stats. It is up
> > to PMD to provide xstats implementation if they want queue stats.
> 
> Agreed, having xstats in driver is the best way.
> Doing what virtio does now would be a good example.

Sure, the xstats implementation is planed to be added in the coming releases.
Currently the gve PMD only have some basic features supported, and will
have the rest features enabled gradually (might co-dev with Google team).
Thanks Stephen and Ferruh for talking about this feature and giving the
detailed explanations and concerns.

>