From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Eric Dumazet In-Reply-To: References: <1300370936.16880.96.camel@gandalf.stny.rr.com> <1300380909.16880.264.camel@gandalf.stny.rr.com> <1300381340.6315.323.camel@edumazet-laptop> <1300385802.16880.348.camel@gandalf.stny.rr.com> Content-Type: text/plain; charset=UTF-8 Date: Thu, 17 Mar 2011 19:38:42 +0100 Message-ID: <1300387122.6315.407.camel@edumazet-laptop> Mime-Version: 1.0 Content-Transfer-Encoding: QUOTED-PRINTABLE Sender: linux-kernel-owner@vger.kernel.org Subject: Re: um: WARNING: at kernel/futex.c:786 __unqueue_futex To: Geert Uytterhoeven Cc: Steven Rostedt , richard -rw- weinberger , laijs@cn.fujitsu.com, LKML , user-mode-linux-devel@lists.sourceforge.net, dvhart@linux.intel.com List-ID: Le jeudi 17 mars 2011 =C3=A0 19:25 +0100, Geert Uytterhoeven a =C3=A9cr= it : > On Thu, Mar 17, 2011 at 19:16, Steven Rostedt w= rote: > > On Thu, 2011-03-17 at 18:02 +0100, Eric Dumazet wrote: > >> Le jeudi 17 mars 2011 =C3=A0 12:55 -0400, Steven Rostedt a =C3=A9c= rit : > >> > Here, test this patch. I'm in the process of committing it now. > >> > It will be two patches, one for the WARN_ON_SMP() change, the ot= her for > >> > the futex change. > >> > > >> > -- Steve > >> > > >> > diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug= =2Eh > >> > index c2c9ba0..25f1e9e 100644 > >> > --- a/include/asm-generic/bug.h > >> > +++ b/include/asm-generic/bug.h > >> > @@ -168,7 +168,7 @@ extern void warn_slowpath_null(const char *f= ile, const int line); > >> > #ifdef CONFIG_SMP > >> > # define WARN_ON_SMP(x) WARN_ON(x) > >> > #else > >> > -# define WARN_ON_SMP(x) do { } while (0) > >> > +# define WARN_ON_SMP(x) ({0;}) > >> > #endif > >> > > >> > >> You meant : > >> > >> # define WARN_ON_SMP(x) ({x;}) > >> > >> or > >> > >> # define WARN_ON_SMP(x) do { } while (x, 0) > >> > >> ? > >> > > > > Does if (do { } while (x, 0)) work? >=20 My point was that WARN_ON(X) always evaluates X once And apparently, WARN_ON_SMP(X) doesnt evaluates X iF !SMP This should be documented, or fixed ;) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel"= in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/