Re: [PATCH v1 1/4] mm: introduce MADV_COLD

[Joel Fernandes]

On Thu, Jun 20, 2019 at 1:01 AM Minchan Kim <minchan@xxxxxxxxxx> wrote:
[snip]
> > > >
> > > > I think to fix this, what you should do is clear the PG_Idle flag if the
> > > > young/accessed PTE bits are set. If PG_Idle is already cleared, then you
> > > > don't need to do anything.
> > >
> > > I'm not sure. What does it make MADV_COLD special?
> > > How about MADV_FREE|MADV_DONTNEED?
> > > Why don't they clear PG_Idle if pte was young at tearing down pte?
> >
> > Good point, so it sounds like those (MADV_FREE|MADV_DONTNEED) also need to be fixed then?
>
> Not sure. If you want it, maybe you need to fix every pte clearing and pte_mkold
> part, which is more general to cover every sites like munmap, get_user_pages and
> so on. Anyway, I don't think it's related to this patchset.

Ok, I can look into this issue on my own when I get time. I'll add it
to my list. No problems with your patch otherwise from my side.

 -Joel