Re: [PATCH v5 2/2] mm: add a field to store names for private anonymous memory

[Sumit Semwal <sumit.semwal@xxxxxxxxxx>]

Hi Matt,

Thanks for the review!
On Wed, 19 Aug 2020 at 20:33, Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:
>
> On Wed, Aug 19, 2020 at 07:46:50PM +0530, Sumit Semwal wrote:
> > +++ b/include/linux/mm_types.h
> > @@ -336,10 +336,18 @@ struct vm_area_struct {
> >       /*
> >        * For areas with an address space and backing store,
> >        * linkage into the address_space->i_mmap interval tree.
> > +      *
> > +      * For private anonymous mappings, a pointer to a null terminated string
> > +      * in the user process containing the name given to the vma, or NULL
> > +      * if unnamed.
> >        */
> > -     struct {
> > -             struct rb_node rb;
> > -             unsigned long rb_subtree_last;
> > +
> > +     union {
> > +             struct {
> > +                     struct rb_node rb;
> > +                     unsigned long rb_subtree_last;
> > +             } interval;
> > +             const char __user *anon_name;
> >       } shared;
>
> You can significantly reduce the size of this patch by doing this instead:
>
>         union {
>                 struct {
>                         struct rb_node rb;
>                         unsigned long rb_subtree_last;
>                 } shared;
>                 const char __user *anon_name;
>         };
>
Thanks, will update in the next version.

Best,
Sumit.