From mboxrd@z Thu Jan 1 00:00:00 1970 From: Martin Josefsson Subject: Re: [RESEND 3/5] [NET]: Protocol Independant Policy Routing Rules Framework Date: Sat, 29 Jul 2006 09:25:21 +0200 Message-ID: <1154157921.23563.46.camel@localhost.localdomain> References: <20060726221100.325687073@postel.suug.ch> <20060726221849.807482409@postel.suug.ch> <20060726.230230.111423566.davem@davemloft.net> <20060727223931.GZ14627@postel.suug.ch> <44C94529.5080605@trash.net> <1154078728.23563.21.camel@localhost.localdomain> <44CABC7D.2080903@trash.net> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-TAg8ycvy9bbaprUzY+rF" Cc: Thomas Graf , David Miller , jmorris@namei.org, netdev@vger.kernel.org, vnuorval@tcs.hut.fi, usagi-core@linux-ipv6.org, yoshfuji@linux-ipv6.org, anttit@tcs.hut.fi Return-path: Received: from mailfront1.citynet.nu ([217.10.96.36]:24299 "EHLO mailfront1.citynet.nu") by vger.kernel.org with ESMTP id S1422679AbWG2HZ6 (ORCPT ); Sat, 29 Jul 2006 03:25:58 -0400 To: Patrick McHardy In-Reply-To: <44CABC7D.2080903@trash.net> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org --=-TAg8ycvy9bbaprUzY+rF Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Sat, 2006-07-29 at 03:40 +0200, Patrick McHardy wrote: > Martin Josefsson wrote: > > As a somewhat related note, I've just digged a bit through RCU land, > > talked to dipankar and mckenney, and discovered that rcu_read_lock() / > > rcu_read_unlock() aren't strictly needed in softirqs since preempt is > > already disabled in softirqs. This means that you can use the result of > > the rcu read-side critical outside of the rcu_read_lock() / >=20 > Thats true, but in this case the code is executed both in softirq- > and user-context. Using rcu_read_lock and still relying on softirq > properties outside the locked section is also very confusing in my > opinion. Yes it is very fishy relying on the softirq properties, especially since they don't apply to -rt kernels and that there might be other changes in this area in the future. It's not recommended. --=20 /Martin --=-TAg8ycvy9bbaprUzY+rF Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.3 (GNU/Linux) iD8DBQBEyw1hWm2vlfa207ERApO6AJ9W+Y2LmgDZoAnanvmOyQ4KcTwyrgCghuLV zv3n1/OuRBLudYwWWUaQZoM= =R/ez -----END PGP SIGNATURE----- --=-TAg8ycvy9bbaprUzY+rF--