[PATCH 03/10] dpaa_eth: add configurable bpool thresholds

[Madalin-Cristian Bucur]

> -----Original Message-----
> From: David Miller [mailto:davem at davemloft.net]
> Sent: Monday, July 27, 2015 2:35 AM
> To: Bucur Madalin-Cristian-B32716
> Cc: joe at perches.com; netdev at vger.kernel.org; linuxppc-
> dev at lists.ozlabs.org; linux-kernel at vger.kernel.org; Wood Scott-B07421;
> Liberman Igal-B31950; ppc at mindchasers.com; pebolle at tiscali.nl;
> joakim.tjernlund at transmode.se
> Subject: Re: [PATCH 03/10] dpaa_eth: add configurable bpool thresholds
> 
> From: Madalin-Cristian Bucur <madalin.bucur at freescale.com>
> Date: Fri, 24 Jul 2015 15:49:39 +0000
> 
> >> -----Original Message-----
> >> From: Joe Perches [mailto:joe at perches.com]
> >> On Wed, 2015-07-22 at 19:16 +0300, Madalin Bucur wrote:
> >> > Allow the user to tweak the refill threshold and the total number
> >> > of buffers in the buffer pool. The provided values are for one CPU.
> >>
> >> Any value in making these module parameters instead?
> >
> > I expect one would (hardly ever) change these to improve some corner
> > cases then use them with the new values. It may help in the tuning process
> > but afterwards the bloat to the bootcmd would probably be  a nuisance.
> 
> I think these should be controlled by the existing ethtool infrastructure.
> 
> Neither the Kconfig mechanism nor module parameters are appropriate, at
> all.

The existing ethtool options are for ring based drivers (ethtool -g / -G).
I would not use those as we are not using rings (they do not map well anyway).

We could introduce special options for our non-ring devices but for these
parameters in particular I'd just resort to defines in the code as it's
improbable one would want to change them.

Madalin