Re: [Lsf-pc] [LSF/MM/BPF TOPIC] Reclamation interactions with RCU

Matthew Wilcox
2024-03-01T02:49:02Z

On Thu, Feb 29, 2024 at 09:39:17PM -0500, Kent Overstreet wrote:
> On Fri, Mar 01, 2024 at 01:16:18PM +1100, NeilBrown wrote:
> > Insisting that GFP_KERNEL allocations never returned NULL would allow us
> > to remove a lot of untested error handling code....
>
> If memcg ever gets enabled for all kernel side allocations we might
> start seeing failures of GFP_KERNEL allocations.

Why would we want that behaviour? A memcg-limited allocation should
behave like any other allocation -- block until we've freed some other
memory in this cgroup, either by swap or killing or ...