Re: [External] Re: [PATCH v2 1/6] mm: migrate: do not migrate HugeTLB page whose refcount is one

[Muchun Song]

On Thu, Jan 7, 2021 at 12:13 AM Michal Hocko <mhocko@xxxxxxxx> wrote:
>
> On Wed 06-01-21 16:47:34, Muchun Song wrote:
> > If the refcount is one when it is migrated, it means that the page
> > was freed from under us. So we are done and do not need to migrate.
>
> Is this common enough that it would warrant the explicit check for each
> migration?

Are you worried about the overhead caused by the check? Thanks.

> --
> Michal Hocko
> SUSE Labs