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

[Matthew Wilcox]

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.