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=-11.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=ham 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 6E0C3C433DF for ; Tue, 18 Aug 2020 20:20:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 484D120709 for ; Tue, 18 Aug 2020 20:20:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726751AbgHRUUd (ORCPT ); Tue, 18 Aug 2020 16:20:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:35898 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725554AbgHRUUc (ORCPT ); Tue, 18 Aug 2020 16:20:32 -0400 Received: from oasis.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 614D1206B5; Tue, 18 Aug 2020 20:20:31 +0000 (UTC) Date: Tue, 18 Aug 2020 16:20:29 -0400 From: Steven Rostedt To: Nick Desaulniers Cc: Alex Dewar , Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Ben Segall , Mel Gorman , LKML , clang-built-linux Subject: Re: [PATCH] sched/cputime: Mark function as __maybe_unused Message-ID: <20200818162029.1692fc82@oasis.local.home> In-Reply-To: References: <20200818170337.805624-1-alex.dewar90@gmail.com> <20200818195746.scpjm3dlg7cfst53@medion> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 18 Aug 2020 13:02:26 -0700 Nick Desaulniers wrote: > On Tue, Aug 18, 2020 at 12:57 PM Alex Dewar wrote: > > > > On Tue, Aug 18, 2020 at 11:13:10AM -0700, Nick Desaulniers wrote: > > > On Tue, Aug 18, 2020 at 10:04 AM Alex Dewar wrote: > > > > > > > > Depending on config options, account_other_time() may not be called > > > > anywhere. Add __maybe_unused flag to fix clang warning. > > > > > > Just curious, would moving this definition to be within an existing > > > preprocessor guard for a particular config also fix the issue? If so, > > > prefer that. If not, __maybe_unused is the way to go. > > > > I don't think that'd work here: it's used within an "#ifdef > > CONFIG_IRQ_TIME_ACCOUNTING" block and a separate "#ifdef > > CONFIG_VIRT_CPU_ACCOUNTING_GEN" one. We could do: > > #if defined(CONFIG_IRQ_TIME_ACCOUNTING) || > > defined(CONFIG_VIRT_CPU_ACCOUNTING) > > ... > > ... but that might be a bit ugly. > > Yeah, ok, in that case it's fine. One issue with __maybe_unused is > that this function will stick around forever if all call sites get > removed. But when the preprocessor checks start getting hairy, > __maybe_unused is maybe simpler. For the reasons you state above, I'm almost thinking ugly may be better. :-/ But there's other places that have the "maybe_unused" in the scheduler code for basically the same reasons, thus I guess it's OK. Acked-by: Steven Rostedt (VMware) -- Steve > Acked-by: Nick Desaulniers > > > > > > > > > > > > > > Signed-off-by: Alex Dewar > > > > --- > > > > kernel/sched/cputime.c | 2 +- > > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > > > diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c > > > > index 5a55d2300452..43ede0d6661c 100644 > > > > --- a/kernel/sched/cputime.c > > > > +++ b/kernel/sched/cputime.c > > > > @@ -252,7 +252,7 @@ static __always_inline u64 steal_account_process_time(u64 maxtime) > > > > /* > > > > * Account how much elapsed time was spent in steal, irq, or softirq time. > > > > */ > > > > -static inline u64 account_other_time(u64 max) > > > > +static inline u64 __maybe_unused account_other_time(u64 max) > > > > { > > > > u64 accounted; > > > > > > > > -- > > > > 2.28.0 > > > > > > > > -- > > > > You received this message because you are subscribed to the Google Groups "Clang Built Linux" group. > > > > To unsubscribe from this group and stop receiving emails from it, send an email to clang-built-linux+unsubscribe@googlegroups.com. > > > > To view this discussion on the web visit https://groups.google.com/d/msgid/clang-built-linux/20200818170337.805624-1-alex.dewar90%40gmail.com. > > > > > > > > > > > > -- > > > Thanks, > > > ~Nick Desaulniers > > >