[PATCH] mm/swap: add function get_total_swap_pages to expose total_swap_pages

[Christian König]

Am 30.01.2018 um 13:28 schrieb Michal Hocko:
> I do think you should completely ignore the size of the swap space. IMHO
> you should forbid further allocations when your current buffer storage
> cannot be reclaimed. So you need some form of feedback mechanism that
> would tell you: "Your buffers have grown too much".

Yeah well, that is exactly what we are trying to do here.

> If you cannot do
> that then simply assume that you cannot swap at all rather than rely on
> having some portion of it for yourself. There are many other users of
> memory outside of your subsystem. Any scaling based on the 50% of resource
> belonging to me is simply broken.

Our intention is not reserve 50% of resources to TTM, but rather allow 
TTM to abort when more than 50% of all resources are used up.

Rogers initial implementation didn't looked like that, but that is just 
a minor mistake we can fix.

Regards,
Christian.