From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next-2.6] net: add rcu protection to netdev->ifalias
Date: Wed, 18 May 2011 06:35:11 +0200
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Cc: David Miller <davem@davemloft.net>, kaber@trash.net,
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Le mercredi 18 mai 2011 =C3=A0 00:39 +0200, Eric Dumazet a =C3=A9crit :

> I dont know, if it happens to be too hard, we'll just stick again rtn=
l
> for "ip link show" ;)
>=20
>=20

I believe I'll take this path, its a bit too hard for the moment, and
need several preliminary steps :

It is making sense trying to get rid of rtnl_trylock() hack with more
fine grained locks, and thus lower pressure on RTNL.

Some synchronize_rcu() calls are done whith RTNL held : All processes
hitting rtnl_trylock() have to enter a busy loop, restarting syscall as
long as the RTNL owner is blocked in synchronize_rcu().