Re: [RFC PATCH v2] mm: Add nodes= arg to memory.reclaim

[Mina Almasry <almasrymina@google.com>]

On Thu, Dec 1, 2022 at 1:32 PM Shakeel Butt <shakeelb@google.com> wrote:
>
> On Tue, Nov 29, 2022 at 06:03:27PM -0800, Mina Almasry wrote:
> [...]
> > diff --git a/mm/vmscan.c b/mm/vmscan.c
> > index 7b8e8e43806b..23fc5b523764 100644
> > --- a/mm/vmscan.c
> > +++ b/mm/vmscan.c
> > @@ -6735,7 +6735,8 @@ unsigned long mem_cgroup_shrink_node(struct mem_cgroup *memcg,
> >  unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg,
> >                                          unsigned long nr_pages,
> >                                          gfp_t gfp_mask,
> > -                                        unsigned int reclaim_options)
> > +                                        unsigned int reclaim_options,
> > +                                        nodemask_t nodemask)
>
> Can you please make this parameter a nodemask_t* and pass NULL instead
> of NODE_MASK_ALL?

Thank you very much for the review. I sure can in the next version. To
be honest I thought about that and made the parameter nodemask_t
because I thought the call sites would be more readable. I.e. this:

    try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL,
MEMCG_RECLAIM_MAY_SWAP,  NODE_MASK_ALL);

Would be more readable than this:

    try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL,
MEMCG_RECLAIM_MAY_SWAP,  NULL);

But the tradeoff is that the callers need include/linux/nodemask.h.
But yes I can fix in the next version.