Re: [PATCH V3 13/18] coresight: tmc: make sysFS and Perf mode mutually exclusive

[Suzuki K Poulose]

On 25/04/16 15:48, Mathieu Poirier wrote:
> On 25 April 2016 at 08:32, Suzuki K Poulose <Suzuki.Poulose@xxxxxxx> wrote:
> > On 22/04/16 18:14, Mathieu Poirier wrote:

> > > +       spin_lock_irqsave(&drvdata->spinlock, flags);
> > > +       if (drvdata->reading) {
> > > +               ret = -EINVAL;
> > > +               goto out;
> > > +       }
> > > +
> > > +       val = local_xchg(&drvdata->mode, mode);
> > > +       /*
> > > +        * In Perf mode there can be only one writer per sink.  There
> > > +        * is also no need to continue if the ETR is already operated
> > > +        * from sysFS.
> > > +        */
> > > +       if (val != CS_MODE_DISABLED) {
> >
> >
> > Could val be CS_MODE_PERF ? In other words, should we be checking :
> >          if (val == CS_MODE_SYSFS)  instead ?
>
> If we check for CS_MODE_SYSFS we also have to check for CS_MODE_PERF,
> which is two checks rather than a single one with the current
> solution.

I am confused now. The comment says, we want to check for sysfs mode and
don't continue in that case. So, we shouldn't be worried about PERF mode.

Suzuki