Re: [PATCH net-next 5/5] r8152: change rx_frag_head_sz and rx_max_agg_num dynamically

From: Maciej Fijalkowski
Date: Thu Aug 08 2019 - 07:50:12 EST


On Thu, 8 Aug 2019 08:52:51 +0000
Hayes Wang <hayeswang@xxxxxxxxxxx> wrote:

> Jakub Kicinski [mailto:jakub.kicinski@xxxxxxxxxxxxx]
> > Sent: Wednesday, August 07, 2019 6:10 AM
> [...]
> > On Tue, 6 Aug 2019 19:18:04 +0800, Hayes Wang wrote:
> > > Let rx_frag_head_sz and rx_max_agg_num could be modified dynamically
> > > through the sysfs.
> > >
> > > Signed-off-by: Hayes Wang <hayeswang@xxxxxxxxxxx>
> >
> > Please don't expose those via sysfs. Ethtool's copybreak and descriptor
> > count should be applicable here, I think.
>
> Excuse me again.
> I find the kernel supports the copybreak of Ethtool.
> However, I couldn't find a command of Ethtool to use it.

Ummm there's set_tunable ops. Amazon's ena driver is making use of it from what
I see. Look at ena_set_tunable() in
drivers/net/ethernet/amazon/ena/ena_ethtool.c.

Maciej

> Do I miss something?
>
> Best Regards,
> Hayes
>