Re: [PATCH v4 06/10] mmap locking API: convert nested write lock sites

[Michel Lespinasse]

On Mon, Apr 20, 2020 at 12:33 PM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:
>
> On Tue, Apr 14, 2020 at 05:43:49PM -0700, Michel Lespinasse wrote:
> > @@ -47,7 +48,7 @@ static inline void activate_mm(struct mm_struct *old, struct mm_struct *new)
> >        * when the new ->mm is used for the first time.
> >        */
> >       __switch_mm(&new->context.id);
> > -     down_write_nested(&new->mmap_sem, 1);
> > +     mmap_write_lock_nested(new, 1);
>
> This should have already been using SINGLE_DEPTH_NESTING.  1 is
> uninformative.

Sure, I can change that.
Note, all mmap_write_lock_nested call sites use single depth nesting,
so I'm not entirely sure if the argument should be passed to
mmap_write_lock_nested in the first place ?

-- 
Michel "Walken" Lespinasse
A program is never fully debugged until the last user dies.