From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9F6A8C33CB6 for ; Fri, 17 Jan 2020 16:50:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7F1FE2064C for ; Fri, 17 Jan 2020 16:50:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726761AbgAQQuj (ORCPT ); Fri, 17 Jan 2020 11:50:39 -0500 Received: from mx2.suse.de ([195.135.220.15]:54064 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726554AbgAQQuj (ORCPT ); Fri, 17 Jan 2020 11:50:39 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 33D23AFDC; Fri, 17 Jan 2020 16:50:34 +0000 (UTC) Received: by ds.suse.cz (Postfix, from userid 10065) id 21DA6DA871; Fri, 17 Jan 2020 17:50:20 +0100 (CET) Date: Fri, 17 Jan 2020 17:50:19 +0100 From: David Sterba To: Josh Poimboeuf Cc: David Sterba , Randy Dunlap , Stephen Rothwell , Linux Next Mailing List , Linux Kernel Mailing List , Linux Btrfs , Peter Zijlstra Subject: Re: linux-next: Tree for Dec 6 (objtool, lots in btrfs) Message-ID: <20200117165019.GM3929@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, Josh Poimboeuf , Randy Dunlap , Stephen Rothwell , Linux Next Mailing List , Linux Kernel Mailing List , Linux Btrfs , Peter Zijlstra References: <20191212184725.db3ost7rcopotr5u@treble> <20191213235054.6k2lcnwa63r26zwi@treble> <20191214054515.ougsr5ykhl3vvy57@treble> <20191217152954.GH3929@suse.cz> <20200110194622.GS3929@twin.jikos.cz> <20200117152805.ncy3z34imzpchg7m@treble> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200117152805.ncy3z34imzpchg7m@treble> User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Sender: linux-next-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-next@vger.kernel.org On Fri, Jan 17, 2020 at 09:28:05AM -0600, Josh Poimboeuf wrote: > On Fri, Jan 10, 2020 at 08:46:22PM +0100, David Sterba wrote: > > On Tue, Dec 17, 2019 at 04:29:54PM +0100, David Sterba wrote: > > > Separating the definitions by #ifdef looks ok, I'd rather do separate > > > definitions of ASSERT too, to avoid the ternary operator. I'll send the > > > patch. > > > > Subject: [PATCH] btrfs: separate definition of assertion failure handlers > > > > There's a report where objtool detects unreachable instructions, eg.: > > > > fs/btrfs/ctree.o: warning: objtool: btrfs_search_slot()+0x2d4: unreachable instruction > > > > This seems to be a false positive due to compiler version. The cause is > > in the ASSERT macro implementation that does the conditional check as > > IS_DEFINED(CONFIG_BTRFS_ASSERT) and not an #ifdef. > > > > To avoid that, use the ifdefs directly. > > > > CC: Josh Poimboeuf > > Reported-by: Randy Dunlap > > Signed-off-by: David Sterba > > --- > > fs/btrfs/ctree.h | 20 ++++++++++++-------- > > 1 file changed, 12 insertions(+), 8 deletions(-) > > This looks quite similar to my patch, would you mind giving me > attribution? So Co-developed-by: or "based on patch from Josh", or something else? > > diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h > > index 569931dd0ce5..f90b82050d2d 100644 > > --- a/fs/btrfs/ctree.h > > +++ b/fs/btrfs/ctree.h > > @@ -3157,17 +3157,21 @@ do { \ > > rcu_read_unlock(); \ > > } while (0) > > > > -__cold > > -static inline void assfail(const char *expr, const char *file, int line) > > +#ifdef CONFIG_BTRFS_ASSERT > > +__cold __noreturn > > +static inline void assertfail(const char *expr, const char *file, int line) > > { > > - if (IS_ENABLED(CONFIG_BTRFS_ASSERT)) { > > - pr_err("assertion failed: %s, in %s:%d\n", expr, file, line); > > - BUG(); > > - } > > + pr_err("assertion failed: %s, in %s:%d\n", expr, file, line); > > + BUG(); > > assertfail() is definitely better than "assfail", but shouldn't you > update the callers so it doesn't break the build? I don't understand what you mean, the helper is not called directly (and build does not fail with or without CONFIG_BTRFS_ASSERT), but always as ASSERT, so I don't see what needs to be updated.