Re: [RFC][PATCH v6 3/7] drm: ttm_pool: Rework ttm_pool_free_page to allow us to use it as a function pointer

[John Stultz]

On Tue, Feb 9, 2021 at 4:14 AM Christian König <christian.koenig@xxxxxxx> wrote:
> Am 05.02.21 um 20:47 schrieb John Stultz:
> > On Fri, Feb 5, 2021 at 12:28 AM Christian König
> > <christian.koenig@xxxxxxx> wrote:
> >> Adding this to all pages would increase the memory footprint drastically.
> > Yea, that's a good point!  Hrm... bummer. I'll have to see if there's
> > some other way I can get the needed context for the free from the
> > generic page-pool side.
>
> What exactly is the problem here?

Me, usually. :)

> As far as I can see we just have the
> lru entry (list_head) and the pool.

Yea, I reworked it to an embedded drm_page_pool struct, but that is
mostly a list_head.

> How the lru is cast to the page can be completely pool implementation
> specific.

Yea, I had it do container_of(), just haven't gotten around to sending
it out yet.

Thanks so much for the feedback and ideas!

thanks
-john