Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752581AbdHQIDy (ORCPT ); Thu, 17 Aug 2017 04:03:54 -0400 Received: from mail-pg0-f66.google.com ([74.125.83.66]:35613 "EHLO mail-pg0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751687AbdHQIDv (ORCPT ); Thu, 17 Aug 2017 04:03:51 -0400 Date: Thu, 17 Aug 2017 16:04:04 +0800 From: Boqun Feng To: Ingo Molnar Cc: Byungchul Park , Thomas Gleixner , peterz@infradead.org, walken@google.com, kirill@shutemov.name, linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org, willy@infradead.org, npiggin@gmail.com, kernel-team@lge.com Subject: Re: [PATCH v8 00/14] lockdep: Implement crossrelease feature Message-ID: <20170817080404.GC11771@tardis> References: <1502089981-21272-1-git-send-email-byungchul.park@lge.com> <20170815082020.fvfahxwx2zt4ps4i@gmail.com> <20170816001637.GN20323@X58A-UD3R> <20170816035842.p33z5st3rr2gwssh@tardis> <20170817074811.csim2edowld4xvky@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="qtZFehHsKgwS5rPz" Content-Disposition: inline In-Reply-To: <20170817074811.csim2edowld4xvky@gmail.com> User-Agent: Mutt/1.8.3 (2017-05-23) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2748 Lines: 85 --qtZFehHsKgwS5rPz Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Aug 17, 2017 at 09:48:11AM +0200, Ingo Molnar wrote: >=20 > * Boqun Feng wrote: >=20 > > --- a/kernel/workqueue.c > > +++ b/kernel/workqueue.c > > @@ -2431,6 +2431,27 @@ struct wq_barrier { > > struct task_struct *task; /* purely informational */ > > }; > > =20 > > +#ifdef CONFIG_LOCKDEP_COMPLETE > > +# define INIT_WQ_BARRIER_ONSTACK(barr, func, target) \ > > +do { \ > > + INIT_WORK_ONSTACK(&(barr)->work, func); \ > > + __set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(&(barr)->work)); \ > > + lockdep_init_map_crosslock((struct lockdep_map *)&(barr)->done.map, \ > > + "(complete)" #barr, \ > > + (target)->lockdep_map.key, 1); \ > > + __init_completion(&barr->done); \ > > + barr->task =3D current; \ > > +} while (0) > > +#else > > +# define INIT_WQ_BARRIER_ONSTACK(barr, func, target) \ > > +do { \ > > + INIT_WORK_ONSTACK(&(barr)->work, func); \ > > + __set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(&(barr)->work)); \ > > + init_completion(&barr->done); \ > > + barr->task =3D current; \ > > +} while (0) > > +#endif >=20 > Is there any progress with this bug? This false positive warning regressi= on is=20 > blocking the locking tree. >=20 I have been trying to reproduce the false positive on my machine, but haven't succeeded. ;-( Have you tried this? But I have been using this patch for a day and haven't shoot my foot yet. > BTW., I don't think the #ifdef is necessary: lockdep_init_map_crosslock s= hould map=20 > to nothing when lockdep is disabled, right? IIUC, lockdep_init_map_crosslock is only defined when CONFIG_LOCKDEP_CROSSRELEASE=3Dy, moreover, completion::map, which used as the parameter of lockdep_init_map_crosslock(), is only defined when CONFIG_LOCKDEP_COMPLETE=3Dy. So the #ifdef is necessary, but maybe we can clean this thing up in the future. I will send a proper patch, so the thing could move forwards. Just a minute ;-) Regards, Boqun >=20 > Thanks, >=20 > Ingo --qtZFehHsKgwS5rPz Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCAAdFiEEj5IosQTPz8XU1wRHSXnow7UH+rgFAlmVTfAACgkQSXnow7UH +ri6eAf+JOu+fAhWne67inCvn0nK1nBw7zl5jHF/esSom/6F8oAO3CvaTW7+fgqe 4JA8NfSZPoxmwY6hUm4odIztCWL34VUZcqrVD0i+ry1TZywKBhbMMWIEzuVwGvIQ w2KZbAloD88AzJ1JgKSPBEU6v6gN+jpMZFMAlvykU/x36V2vFFsPIORtBaH35rh4 kalt8VXxJV5KgyUoQSNCWnbyWc7/+OX1zlAzjNTiLT9r2LBHxCYjxza4xdvSClsF D8PkWz8AOA7MAJXsjCDXsJAP1+Yr0ah/QhAVfvFKaP98yF3lJKr7BSDT7j3/conb 46gJq6QZ3ZVG5jJ27o9cCdwOl++Gbw== =jXYI -----END PGP SIGNATURE----- --qtZFehHsKgwS5rPz--