Re: [PATCH 1/1] mm, oom_adj: don't loop through tasks in __set_oom_adj when not necessary

From: Michal Hocko
Date: Thu Aug 20 2020 - 12:26:54 EST


On Thu 20-08-20 08:56:53, Suren Baghdasaryan wrote:
[...]
> Catching up on the discussion which was going on while I was asleep...
> So it sounds like there is a consensus that oom_adj should be moved to
> mm_struct rather than trying to synchronize it among tasks sharing mm.
> That sounds reasonable to me too. Michal answered all the earlier
> questions about this patch, so I won't be reiterating them, thanks
> Michal. If any questions are still lingering about the original patch
> I'll be glad to answer them.

I think it still makes some sense to go with a simpler (aka less tricky)
solution which would be your original patch with an incremental fix for
vfork and the proper ordering (http://lkml.kernel.org/r/20200820124109.GI5033@xxxxxxxxxxxxxx)
and then make a more complex shift to mm struct on top of that. The
former will be less tricky to backport to stable IMHO.
--
Michal Hocko
SUSE Labs