Subject: Re: [PATCH 1/2] drivers/base/node: merge register_one_node() and register_node() to a single function.

From: Mike Rapoport <[email-masked]>
Date: Thu, 25 Sep 2025 12:34:20 +0300

On Thu, Sep 25, 2025 at 10:54:07AM +0200, David Hildenbrand wrote:
> On 24.09.25 20:40, Donet Tom wrote:
> > register_one_node() and register_node() are small functions.
> > This patch merges them into a single function named register_node()
> > to improve code readability.
> > 
> > No functional changes are introduced.
> > 
> > Signed-off-by: Donet Tom <[email-masked]>
> > ---
> 
> [...]
> 
> >   /**
> >    * unregister_node - unregister a node device
> >    * @node: node going away
> > @@ -869,7 +842,13 @@ void register_memory_blocks_under_node_hotplug(int nid, unsigned long start_pfn,
> >   }
> >   #endif /* CONFIG_MEMORY_HOTPLUG */
> > -int register_one_node(int nid)
> > +/*
> 
> We can directly convert this to proper kernel doc by using /**
> 
> > + * register_node - Setup a sysfs device for a node.
> > + * @nid - Node number to use when creating the device.
> > + *
> > + * Initialize and register the node device.
> 
> and briefly describing what the return value means
> 
> "Returns 0 on success, ..."

For kernel-doc it should be

Return: 0 on success, ...

> 
> > + */
> > +int register_node(int nid)
> >   {
> >   	int error;
> >   	int cpu;
> > @@ -880,14 +859,23 @@ int register_one_node(int nid)
> >   		return -ENOMEM;
> >   	INIT_LIST_HEAD(&node->access_list);
> > -	node_devices[nid] = node;
> > -	error = register_node(node_devices[nid], nid);
> > +	node->dev.id = nid;
> > +	node->dev.bus = &node_subsys;
> > +	node->dev.release = node_device_release;
> > +	node->dev.groups = node_dev_groups;
> > +
> > +	error = device_register(&node->dev);
> >   	if (error) {
> > -		node_devices[nid] = NULL;
> 
> Wondering why we did have this temporary setting of the node_devices[] in
> there. But I cannot immediately spot why it was required.

register_cpu_under_node() references node_devices, so that assignment can
be moved just before the loop that adds CPUs to node.
 
> -- 
> Cheers
> David / dhildenb

-- 
Sincerely yours,
Mike.