Re: [PATCH v4 2/2] mm/hmm/test: add self tests for HMM

[Jason Gunthorpe]

On Tue, Nov 12, 2019 at 01:51:11PM -0800, Ralph Campbell wrote:

> > > +static int dmirror_invalidate_range_start(struct mmu_notifier *mn,
> > > +				const struct mmu_notifier_range *update)
> > > +{
> > > +	struct dmirror *dmirror = container_of(mn, struct dmirror, notifier);
> > > +
> > > +	if (mmu_notifier_range_blockable(update))
> > > +		mutex_lock(&dmirror->mutex);
> > > +	else if (!mutex_trylock(&dmirror->mutex))
> > > +		return -EAGAIN;
> > > +
> > > +	dmirror_do_update(dmirror, update->start, update->end);
> > > +	mutex_unlock(&dmirror->mutex);
> > > +	return 0;
> > > +}
> > 
> > Can we adopts this to Jasons new interval tree invalidate?
> 
> Well, it would mean registering for the whole process address space.
> I'll give it a try.

I'm not sure it makes much sense that this testing is essentially
modeled after nouveau's usage which is very strange compared to the
other drivers.

Jason