Hi Dan, On Sat, Dec 10, 2016 at 10:28:51PM -0800, Dan Williams wrote: > In preparation for other callers of these routines make the locking the > responsibility of the caller. > > Signed-off-by: Dan Williams <dan.j.willi...@intel.com> > --- > drivers/dax/dax.c | 30 ++++++++++++++++++++++++------ > 1 file changed, 24 insertions(+), 6 deletions(-) > > diff --git a/drivers/dax/dax.c b/drivers/dax/dax.c > index d878a56cf3e3..5b65eaff6ace 100644 > --- a/drivers/dax/dax.c > +++ b/drivers/dax/dax.c > @@ -90,11 +90,11 @@ static unsigned long long dax_region_avail_size( > unsigned long long size; > struct resource *res; > > - mutex_lock(&dax_region->lock); > + WARN_ON_ONCE(!mutex_is_locked(&dax_region->lock));
I'd prefer it a lockdep_assert_held(&dex_region->lock). This of cause has the drawback that it won't trigger w/o lockdep but enabled, but I don't think it's the responibility of a production kernel to have this warnings anyway. On the flip side you get all the lockdep beauty for free with it. > + > size = resource_size(&dax_region->res); > for_each_dax_region_resource(dax_region, res) > size -= resource_size(res); > - mutex_unlock(&dax_region->lock); > > return size; > } [...] > +static unsigned long long dax_dev_size(struct dax_dev *dax_dev) > { > - struct dax_dev *dax_dev = to_dax_dev(dev); > + struct dax_region *dax_region = dax_dev->region; > unsigned long long size = 0; > int i; > > + WARN_ON_ONCE(!mutex_is_locked(&dax_region->lock)); > + See above > for (i = 0; i < dax_dev->num_resources; i++) > size += resource_size(dax_dev->res[i]); > > + return size; > +} > + Byte, Johannes