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

[Shakeel Butt]

On Tue, Nov 11, 2025 at 04:36:14PM +0800, Qi Zheng wrote:
> Hi Shakeel,
> 
> On 11/11/25 7:20 AM, 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.
> 
> Generally, places that call __mod_lruvec_state() also call
> __mod_zone_page_state(), and it also has the corresponding optimized
> version (mod_zone_page_state()). It seems necessary to clean that up
> as well, so that those disabling-IRQs that are only used for updating
> vmstat can be removed.

I agree, please take a stab at that.