Re: [PATCH 0/4] memcg: cleanup the memcg stats interfaces

[Qi Zheng]

Hi,

On 11/11/25 8:59 AM, Harry Yoo wrote:
> On Mon, Nov 10, 2025 at 03:20:04PM -0800, Shakeel Butt wrote:
> > The memcg stats are safe against irq (and nmi) context and thus does not
> > require disabling irqs. However for some stats which are also maintained
> > at node level, it is using irq unsafe interface and thus requiring the
> > users to still disables irqs or use interfaces which explicitly disables
> > irqs. Let's move memcg code to use irq safe node level stats function
> > which is already optimized for architectures with HAVE_CMPXCHG_LOCAL
> > (all major ones), so there will not be any performance penalty for its
> > usage.

Good job. Thanks!

> Are you or Qi planning a follow-up that converts spin_lock_irq() to
> spin_lock() in places where they disabled IRQs was just to update vmstat?

Perhaps this change could be implemented together in [PATCH 1/4]?

Of course, it's also reasonable to make it a separate patch. If we
choose this method, I’m fine with either me or Shakeel doing it.

> Qi's zombie memcg series will depends on that work I guess..

Yes, and there are other places that also need to be converted, such as
__folio_migrate_mapping().

Thanks,
Qi

>