From owner-svn-src-projects@FreeBSD.ORG Sat Sep 8 15:38:45 2012 Return-Path: Delivered-To: svn-src-projects@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A9ABB1065678; Sat, 8 Sep 2012 15:38:45 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from mail.zoral.com.ua (mx0.zoral.com.ua [91.193.166.200]) by mx1.freebsd.org (Postfix) with ESMTP id 1E1978FC14; Sat, 8 Sep 2012 15:38:43 +0000 (UTC) Received: from skuns.kiev.zoral.com.ua (localhost [127.0.0.1]) by mail.zoral.com.ua (8.14.2/8.14.2) with ESMTP id q88FcpGY054798; Sat, 8 Sep 2012 18:38:51 +0300 (EEST) (envelope-from kostikbel@gmail.com) Received: from deviant.kiev.zoral.com.ua (kostik@localhost [127.0.0.1]) by deviant.kiev.zoral.com.ua (8.14.5/8.14.5) with ESMTP id q88FcdXt090165; Sat, 8 Sep 2012 18:38:39 +0300 (EEST) (envelope-from kostikbel@gmail.com) Received: (from kostik@localhost) by deviant.kiev.zoral.com.ua (8.14.5/8.14.5/Submit) id q88FcdwY090164; Sat, 8 Sep 2012 18:38:39 +0300 (EEST) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: deviant.kiev.zoral.com.ua: kostik set sender to kostikbel@gmail.com using -f Date: Sat, 8 Sep 2012 18:38:39 +0300 From: Konstantin Belousov To: Attilio Rao Message-ID: <20120908153839.GF33100@deviant.kiev.zoral.com.ua> References: <20120730143943.GY2676@deviant.kiev.zoral.com.ua> <5016A21B.6090409@FreeBSD.org> <5016A8E4.7070405@FreeBSD.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="Cxx16vhE7hPQXf14" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.3i X-Virus-Scanned: clamav-milter 0.95.2 at skuns.kiev.zoral.com.ua X-Virus-Status: Clean X-Spam-Status: No, score=-4.0 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00 autolearn=ham version=3.2.5 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on skuns.kiev.zoral.com.ua Cc: Davide Italiano , svn-src-projects@freebsd.org, src-committers@freebsd.org, Andriy Gapon Subject: Re: svn commit: r238907 - projects/calloutng/sys/kern X-BeenThere: svn-src-projects@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the src " projects" tree" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 08 Sep 2012 15:38:45 -0000 --Cxx16vhE7hPQXf14 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Sep 07, 2012 at 11:35:15PM +0100, Attilio Rao wrote: > On Mon, Jul 30, 2012 at 9:39 PM, Attilio Rao wrote: > > On Mon, Jul 30, 2012 at 4:31 PM, Andriy Gapon wrote: > >> on 30/07/2012 18:04 Attilio Rao said the following: > >>> On 7/30/12, Andriy Gapon wrote: > >>>> on 30/07/2012 17:56 Attilio Rao said the following: > >>>>> More explicitly, I think such combination TDP_NOSLEEPING + > >>>>> TDP_NOBLOCKING (name invented) should be set on entering the interr= upt > >>>>> context, not only related to this part of callouts. This would be a > >>>>> very good help for catching buggy situations. > >>>> > >>>> Something very tangential. I think it would also be nice to check i= f a > >>>> thread has > >>>> any(?) locks held when returning to userland. > >>> > >>> This happens already for INVARIANTS case, with td_locks counters. > >>> In the !INVARIANTS case, this doesn't happen because you don't want to > >>> add the burden to bump td_locks for the fast case and I think it is a > >>> good approach. > >> > >> Ah, I missed that, thank you. > >> BTW, it seems that td_locks is checked twice in normal syscallret() pa= th: once in > >> syscallret() itself and then in userret(). On this note, would it mak= e sense to > >> move the whole nine yards of asserts from syscallret() to userret()? > >> I mean it might make sense to have those checks (td_critnest, td_pflag= s) in other > >> paths to userland. > > > > Nice catch. > > The checks were added to syscallret() in r208453. While this is fine, > > I think that putting them in userret() may give them more exposure and > > cover also cases like traps which are not covered right now. > > If you want to make a patch that moves these conditions in userret() > > I'd be in favor of it. >=20 > More specifically, what do you think about this patch?: > http://www.freebsd.org/~attilio/userret_diag.patch >=20 > Of course I moved the XEN par too before the checks. > The patch survived to few consecutive and parallel buildworlds, FWIW. At least in fork_return(), the last assert which checks that Giant is not held, is no longer needed. I had similar thought from the time when I added TDP_NOFAULTING check to the syscallret(), but the loss of the syscall name in the panic output always stopped me. --Cxx16vhE7hPQXf14 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (FreeBSD) iEYEARECAAYFAlBLZn8ACgkQC3+MBN1Mb4ikzACg8s+t4a+wwanhpiFRFacRjuIZ IzcAoPZ+mhAnSotFwYjMeVj574WW9ier =xZiz -----END PGP SIGNATURE----- --Cxx16vhE7hPQXf14--