Re: [PATCH 3/8] scsi: ufshpb: Add region's reads counter

[gregkh@xxxxxxxxxxxxxxxxxxx]

On Mon, Feb 01, 2021 at 07:51:19AM +0000, Avri Altman wrote:
> > 
> > On Mon, Feb 01, 2021 at 07:12:53AM +0000, Avri Altman wrote:
> > > > > +#define WORK_PENDING 0
> > > > > +#define ACTIVATION_THRSHLD 4 /* 4 IOs */
> > > > Rather than fixing it with macro, how about using sysfs and make it
> > > > configurable?
> > > Yes.
> > > I will add a patch making all the logic configurable.
> > > As all those are hpb-related parameters, I think module parameters are
> > more adequate.
> > 
> > No, this is not the 1990's, please never add new module parameters to
> > drivers.  If not for the basic problem of they do not work on a
> > per-device basis, but on a per-driver basis, which is what you almost
> > never want.
> OK.
> 
> > 
> > But why would you want to change this value, why can't the driver "just
> > work" and not need manual intervention?
> It is.
> But those are a knobs each vendor may want to tweak,
> So it'll be optimized with its internal device's implementation.
> 
> Tweaking the parameters, as well as the entire logic, is really an endless task.
> Some logic works better for some scenarios, while falling behind on others.

Shouldn't the hardware know how to handle this dynamically?  If not, how
is a user going to know?

> How about leaving it for now, to be elaborated it in the future?

I do not care, just do not make it a module parameter for the reason
that does not work on a per-device basis.

> Maybe even can be a part of a scheme, to make the logic proprietary?

What do you mean by "proprietary"?

thanks,

greg k-h