Subject: Re: [RFC PATCH net-next v3 1/4] netns: add genl cmd to add and get peer netns ids

From: Nicolas Dichtel <[email-masked]>
Date: Fri, 03 Oct 2014 14:22:26 +0200

Le 02/10/2014 21:33, Eric W. Biederman a écrit :
> Nicolas Dichtel <[email-masked]> writes:
>
>> With this patch, a user can define an id for a peer netns by providing a FD or a
>> PID. These ids are local to netns (ie valid only into one netns).
>>
>> This will be useful for netlink messages when a x-netns interface is
>> dumped.
>
> You have a "id -> struct net *" table but you don't have a
> "struct net * -> id" table which looks like it will impact the
> performance of peernet2id at scale.
It is indirectly stores in 'struct idr'. It can be optimized later, with a
proper algorithm to find quickly this 'struct net *' (hash table? something
else?). A basic algorithm will not be more scalable than the current
idr_for_each().