From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next-2.6] phonet: use call_rcu for phonet device
 free
Date: Mon, 07 Jun 2010 15:49:43 +0200
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Cc: Jiri Pirko <jpirko@redhat.com>, netdev@vger.kernel.org,
	davem@davemloft.net
To: =?ISO-8859-1?Q?R=E9mi?= Denis-Courmont <remi@remlab.net>
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Le lundi 07 juin 2010 =C3=A0 15:43 +0200, R=C3=A9mi Denis-Courmont a =C3=
=A9crit :
> On Mon, 7 Jun 2010 15:27:39 +0200, Jiri Pirko <jpirko@redhat.com> wro=
te:
> > Use call_rcu rather than synchronize_rcu.
> >=20
> > Signed-off-by: Jiri Pirko <jpirko@redhat.com>
>=20
> This looks fine to me, but what is the goal here? The RCU documentati=
on
> seems to imply that synchronize_rcu() is preferable over call_rcu() w=
hen at
> all possible.
>=20

Thats not exactly that.

synchronize_rcu() is easier, in respect of memory use.
But its drawback is current thread is blocked for several milli seconds=
=2E

In the end, call_rcu() is more scalable.

Acked-by: Eric Dumazet <eric.dumazet@gmail.com>