[PATCH 1/2] mm/vmalloc: Add interfaces to free unused page table

[Kani, Toshi]

On Thu, 2018-03-08 at 14:07 -0800, Matthew Wilcox wrote:
> On Thu, Mar 08, 2018 at 03:56:30PM +0000, Kani, Toshi wrote:
> > On Wed, 2018-03-07 at 20:00 -0800, Matthew Wilcox wrote:
> > > On Wed, Mar 07, 2018 at 11:32:26AM -0700, Toshi Kani wrote:
> > > > +/**
> > > > + * pud_free_pmd_page - clear pud entry and free pmd page
> > > > + *
> > > > + * Returns 1 on success and 0 on failure (pud not cleared).
> > > > + */
> > > > +int pud_free_pmd_page(pud_t *pud)
> > > > +{
> > > > +	return pud_none(*pud);
> > > > +}
> > > 
> > > Wouldn't it be clearer if you returned 'bool' instead of 'int' here?
> > 
> > I thought about it and decided to use 'int' since all other pud/pmd/pte
> > interfaces, such as pud_none() above, use 'int'.
> 
> These interfaces were introduced before we had bool ... I suspect nobody's
> taken the time to go through and convert them all.

I see.  Since this patchset already changes core, arm and x86, and will
be back ported to stables.  So, if you do not mind, I'd like to leave it
consistent with others with 'int', and make the footstep minimum.

Thanks,
-Toshi