Re: Re: [tpmdd-devel] [PATCH] tpm: improve tpm_tis send() performance by ignoring burstcount

From: Jarkko Sakkinen
Date: Tue Aug 15 2017 - 02:08:33 EST


On Mon, Aug 14, 2017 at 08:03:05AM -0400, Mimi Zohar wrote:
> On Mon, 2017-08-14 at 13:56 +0300, Jarkko Sakkinen wrote:
>
> > > > > I would like to see tpm_msleep() wrapper to replace current msleep()
> > > > > usage across the subsystem before considering this. I.e. wrapper that
> > > > > internally uses usleep_range(). This way we can mechanically convert
> > > > > everything to a more low latency option.
> > > >
> > > > Fine.  I assume you meant tpm_sleep(), not tpm_msleep().
> > >
> > > I think it would sense to have a function that takes msecs because msecs
> > > are mostly used everywhere in the subsystem. This way we don't have to
> > > change any of the existing constants.
>
> For now converting from msleep() to tpm_msleep() will be straight
> forward.  Internally we would just use usleep_range().
>
> Going forward, my concern is that even 1 msec might be too long for
> some of these sleeps.
>
> Mimi

We can revisit this. I would take the simple route right now.

/Jarkko