Re: [PATCH 2/2] mm/vmpressure: split v1 userspace eventfd code into vmpressure-v1.c

[Usama Arif <usama.arif@linux.dev>]

On 25/06/2026 10:00, Michal Koutný wrote:
> On Sat, Jun 06, 2026 at 04:41:34AM -0700, Usama Arif <usama.arif@linux.dev> wrote:
>> Clean up mm/vmpressure.c by separating the cgroup v1 userspace eventfd
>> interface from the shared and v2 in-kernel code.
>>
>> Currently, almost half of mm/vmpressure.c exists to serve tree=true:
>> struct vmpressure_event, the events list and its mutex, the work_struct
>> and vmpressure_work_fn that drains tree_scanned/tree_reclaimed, the
>> parent walk, vmpressure_event(), vmpressure_register_event(),
>> vmpressure_unregister_event(), and vmpressure_prio() (which always
>> calls vmpressure() with tree=true).
>>
>> Move it all into a new mm/vmpressure-v1.c built only when
>> CONFIG_MEMCG_V1=y (following the existing memcontrol-v1.o pattern).
> 
> Thanks for this dissection.
> 
>> @@ -283,14 +152,8 @@ void vmpressure(gfp_t gfp, int order, struct mem_cgroup *memcg, bool tree,
>>  		return;
>>  
>>  	if (tree) {
>> -		spin_lock(&vmpr->sr_lock);
>> -		scanned = vmpr->tree_scanned += scanned;
>> -		vmpr->tree_reclaimed += reclaimed;
>> -		spin_unlock(&vmpr->sr_lock);
>> -
>> -		if (scanned < vmpressure_win)
>> -			return;
>> -		schedule_work(&vmpr->work);
>> +		vmpressure_v1_account_tree(vmpr, scanned, reclaimed);
>> +		return;
>>  	} else {
>>  		enum vmpressure_levels level;
>>  
> 
> This return; looks weird, I'd either
> a) drop it or 
> b) keep it + de-indent the rest of the vmpressure().

Thanks! Will do.