Re: [PATCH v6 2/3] mm/mempolicy: Prepare weighted interleave sysfs for memory hotplug

[Dan Williams]

Jonathan Cameron wrote:
> On Fri, 4 Apr 2025 16:46:20 +0900
> Rakie Kim <rakie.kim@xxxxxx> wrote:
> 
> > Previously, the weighted interleave sysfs structure was statically
> > managed during initialization. This prevented new nodes from being
> > recognized when memory hotplug events occurred, limiting the ability
> > to update or extend sysfs entries dynamically at runtime.
> > 
> > To address this, this patch refactors the sysfs infrastructure and
> > encapsulates it within a new structure, `sysfs_wi_group`, which holds
> > both the kobject and an array of node attribute pointers.
> > 
> > By allocating this group structure globally, the per-node sysfs
> > attributes can be managed beyond initialization time, enabling
> > external modules to insert or remove node entries in response to
> > events such as memory hotplug or node online/offline transitions.
> > 
> > Instead of allocating all per-node sysfs attributes at once, the
> > initialization path now uses the existing sysfs_wi_node_add() and
> > sysfs_wi_node_delete() helpers. This refactoring makes it possible
> > to modularly manage per-node sysfs entries and ensures the
> > infrastructure is ready for runtime extension.
> > 
> > Signed-off-by: Rakie Kim <rakie.kim@xxxxxx>
> > Signed-off-by: Honggyu Kim <honggyu.kim@xxxxxx>
> > Signed-off-by: Yunjeong Mun <yunjeong.mun@xxxxxx>
> > Reviewed-by: Gregory Price <gourry@xxxxxxxxxx>
> Hi Rakie,
> 
> Some things I was requesting in patch 1 are done here.
> Mostly I think what is wanted is moving some of that
> refactoring back to that patch rather than here.
> 
> Some of the label and function naming needs another look.
> 
> Jonathan
[..]
> > @@ -3430,27 +3437,24 @@ static ssize_t node_store(struct kobject *kobj, struct kobj_attribute *attr,
> >  	return count;
> >  }
> >  
> > -static struct iw_node_attr **node_attrs;
> > -
> > -static void sysfs_wi_node_release(struct iw_node_attr *node_attr,
> > -				  struct kobject *parent)
> > +static void sysfs_wi_node_delete(int nid)
> 
> Maybe stick to release naming to match the sysfs_wi_release()
> below? I don't really care about this.

I had asked for "delete" to pair with "add" and to not get confused with
a final kobject_put() callback.