RE: [linux-pm] [PATCH v4] PM: add statistics debugfs file for suspend to ram

Mansoor, Illyas
2011-08-10T20:20:46Z

> On Thu, Aug 11, 2011 at 01:22:56AM +0530, Mansoor, Illyas wrote:
> > static pm_message_t pm_transition;
> > > > >
> > > > > @@ -464,8 +465,12 @@ void dpm_resume_noirq(pm_message_t state)
> > > > > mutex_unlock(&dpm_list_mtx);
> > > > >
> > > > > error = device_resume_noirq(dev, state);
> > > > > - if (error)
> > > > > + if (error) {
> > > > > + suspend_stats.failed_resume_noirq++;
> > > > > + dpm_save_failed_step(SUSPEND_RESUME_NOIRQ);
> > > > > + dpm_save_failed_dev(dev_name(dev));
> > > >
> > > > Please make these statistics conditionally enabled, so on a production
> system
> > > > If we need to disable these statistics code we should be able to do so.
> > >
> > > Why, are they taking time or space that is needed for something else?
> > > What's the downside here of just not always having this enabled?
> >
> > Why have something that is not required/Used?
>
> Because someone might need it and rebuilding a kernel isn't possible on
> lots of devices.

Agreed.

>
> > Its only useful if DEBUGFS is configured anyways
>
> Almost all systems these days have debugfs enabled, so that's a moot
> point.

We could do the same for this as well, since DEBUGFS is still a compile time
Option even thou many enable it by default we don't make it part of the kernel isn't it.

-Illyas