From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [RFC net-next-2.6] can: replace spinlocks with mutexes
Date: Wed, 20 Apr 2011 17:39:14 +0200
Message-ID: <1303313954.3186.117.camel@edumazet-laptop>
References: <4DAEFC55.2010500@hartkopp.net>
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Cc: David Miller <davem@davemloft.net>,
	Linux Netdev List <netdev@vger.kernel.org>,
	Kurt Van Dijck <kurt.van.dijck@eia.be>,
	Urs Thuermann <urs@isnogud.escape.de>
To: Oliver Hartkopp <socketcan@hartkopp.net>
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Le mercredi 20 avril 2011 =C3=A0 17:31 +0200, Oliver Hartkopp a =C3=A9c=
rit :
> This patch removes spinlocks for the CAN netdevice specific receive l=
ists.
> The RCU-based receive lists can be modified from process context or f=
rom the
> netdevice notifier call. As both might sleep we can safely replace th=
e
> spinlocks with mutexes.
>=20
> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
>=20
> ---

But... why ?

A spinlock is faster/smaller than a mutex.

Maybe you wanted to _remove_ spinlock, since/if writer hold RTNL and
doesnt need to exclude another writer(s) ?

Note : I did not check the RTNL assertion, you might add appropriate
ASSERT_RTNL() calls just to be 100% safe.