Re: [patch net-next rfc 2/7] net: introduce name_node struct to be used in hashlist

[Stephen Hemminger <stephen@networkplumber.org>]

On Fri, 19 Jul 2019 21:17:40 +0200
Jiri Pirko <jiri@resnulli.us> wrote:

> Fri, Jul 19, 2019 at 06:29:36PM CEST, stephen@networkplumber.org wrote:
> >On Fri, 19 Jul 2019 13:00:24 +0200
> >Jiri Pirko <jiri@resnulli.us> wrote:
> >  
> >> From: Jiri Pirko <jiri@mellanox.com>
> >> 
> >> Signed-off-by: Jiri Pirko <jiri@mellanox.com>
> >> ---
> >>  include/linux/netdevice.h | 10 +++-
> >>  net/core/dev.c            | 96 +++++++++++++++++++++++++++++++--------
> >>  2 files changed, 86 insertions(+), 20 deletions(-)
> >> 
> >> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
> >> index 88292953aa6f..74f99f127b0e 100644
> >> --- a/include/linux/netdevice.h
> >> +++ b/include/linux/netdevice.h
> >> @@ -918,6 +918,12 @@ struct dev_ifalias {
> >>  struct devlink;
> >>  struct tlsdev_ops;
> >>  
> >> +struct netdev_name_node {
> >> +	struct hlist_node hlist;
> >> +	struct net_device *dev;
> >> +	char *name  
> >
> >You probably can make this const char *  

Don't bother, it looks ok as is. the problem is you would have
to cast it when calling free.

> >Do you want to add __rcu to this list?  
> 
> Which list?
> 

       struct netdev_name_node __rcu *name_node;

You might also want to explictly init the hlist node rather
than relying on the fact that zero is an empty node ptr.

 
 static struct netdev_name_node *netdev_name_node_alloc(struct net_device *dev,
-                                                      char *name)
+                                                      const char *name)
 {
        struct netdev_name_node *name_node;
 
-       name_node = kzalloc(sizeof(*name_node), GFP_KERNEL);
+       name_node = kmalloc(sizeof(*name_node));
        if (!name_node)
                return NULL;
+
+       INIT_HLIST_NODE(&name_node->hlist);
        name_node->dev = dev;
        name_node->name = name;
        return name_node;