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

[Harry Yoo]

On Tue, Nov 11, 2025 at 11:07:09AM +0800, Qi Zheng wrote:
> 
> 
> On 11/11/25 11:00 AM, Shakeel Butt wrote:
> > On Tue, Nov 11, 2025 at 10:48:18AM +0800, Qi Zheng wrote:
> > > Hi Shakeel,
> > > 
> > > On 11/11/25 10:39 AM, Shakeel Butt wrote:
> > > > On Tue, Nov 11, 2025 at 10:23:15AM +0800, Qi Zheng wrote:
> > > > > Hi,
> > > > > 
> > > > [...]
> > > > > > 
> > > > > > 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.
> > > > > 
> > > > 
> > > > Let's do it separately as I wanted to keep the memcg related changes
> > > > self-contained.
> > > 
> > > OK.
> > > 
> > > > 
> > > > Qi, can you please take a stab at that?
> > > 
> > > Sure, I will do 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().
> > > > 
> > > > I see __mod_zone_page_state() usage in __folio_migrate_mapping() and
> > > > using the same reasoning we can convert it to use mod_zone_page_state().
> > > > Where else do you need to do these conversions (other than
> > > > __folio_migrate_mapping)?
> > > 
> > > I mean converting these places to use spin_lock() instead of
> > > spin_lock_irq().
> > 
> > For only stats, right?
> 
> Right, for thoes places where they disabled IRQs was just to update
> vmstat.

...Or if they disabled IRQs for other reasons as well, we can still move
vmstat update code outside the IRQ disabled region.

-- 
Cheers,
Harry / Hyeonggon