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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,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 C05A6C64E90 for ; Fri, 20 Nov 2020 19:16:47 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id F1F8B24196 for ; Fri, 20 Nov 2020 19:16:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F1F8B24196 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id EE67A6B0036; Fri, 20 Nov 2020 14:16:45 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E6F5B6B005C; Fri, 20 Nov 2020 14:16:45 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D35256B005D; Fri, 20 Nov 2020 14:16:45 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0056.hostedemail.com [216.40.44.56]) by kanga.kvack.org (Postfix) with ESMTP id 9D4D16B0036 for ; Fri, 20 Nov 2020 14:16:45 -0500 (EST) Received: from smtpin19.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 3A6F31F1A for ; Fri, 20 Nov 2020 19:16:45 +0000 (UTC) X-FDA: 77505753570.19.girl60_61103b42734d Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin19.hostedemail.com (Postfix) with ESMTP id D05E91ACEA4 for ; Fri, 20 Nov 2020 19:16:44 +0000 (UTC) X-HE-Tag: girl60_61103b42734d X-Filterd-Recvd-Size: 3324 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf16.hostedemail.com (Postfix) with ESMTP for ; Fri, 20 Nov 2020 19:16:44 +0000 (UTC) Received: from gandalf.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 308AD22240; Fri, 20 Nov 2020 19:16:41 +0000 (UTC) Date: Fri, 20 Nov 2020 14:16:39 -0500 From: Steven Rostedt To: Marco Elver Cc: "Paul E. McKenney" , Anders Roxell , Andrew Morton , Alexander Potapenko , Dmitry Vyukov , Jann Horn , Mark Rutland , Linux Kernel Mailing List , Linux-MM , kasan-dev , rcu@vger.kernel.org, Peter Zijlstra , Tejun Heo , Lai Jiangshan , linux-arm-kernel@lists.infradead.org Subject: Re: linux-next: stall warnings and deadlock on Arm64 (was: [PATCH] kfence: Avoid stalling...) Message-ID: <20201120141639.3896a3c8@gandalf.local.home> In-Reply-To: <20201120181737.GA3301774@elver.google.com> References: <20201118225621.GA1770130@elver.google.com> <20201118233841.GS1437@paulmck-ThinkPad-P72> <20201119125357.GA2084963@elver.google.com> <20201119151409.GU1437@paulmck-ThinkPad-P72> <20201119170259.GA2134472@elver.google.com> <20201119184854.GY1437@paulmck-ThinkPad-P72> <20201119193819.GA2601289@elver.google.com> <20201119213512.GB1437@paulmck-ThinkPad-P72> <20201120141928.GB3120165@elver.google.com> <20201120102613.3d18b90e@gandalf.local.home> <20201120181737.GA3301774@elver.google.com> 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, 20 Nov 2020 19:17:37 +0100 Marco Elver wrote: > > > +++ b/kernel/rcu/Makefile > > > @@ -3,6 +3,13 @@ > > > # and is generally not a function of system call inputs. > > > KCOV_INSTRUMENT := n > > > > > > +ifdef CONFIG_FUNCTION_TRACER > > > +CFLAGS_REMOVE_update.o = $(CC_FLAGS_FTRACE) > > > +CFLAGS_REMOVE_sync.o = $(CC_FLAGS_FTRACE) > > > +CFLAGS_REMOVE_srcutree.o = $(CC_FLAGS_FTRACE) > > > +CFLAGS_REMOVE_tree.o = $(CC_FLAGS_FTRACE) > > > +endif > > > + > > > > Can you narrow it down further? That is, do you really need all of the > > above to stop the stalls? > > I tried to reduce it to 1 or combinations of 2 files only, but that > didn't work. I'm curious if this would help at all? diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 2a52f42f64b6..d020ecefd151 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1094,7 +1094,7 @@ static void rcu_disable_urgency_upon_qs(struct rcu_data *rdp) * if the current CPU is not in its idle loop or is in an interrupt or * NMI handler, return true. */ -bool rcu_is_watching(void) +notrace bool rcu_is_watching(void) { bool ret; Although I don't see it in the recursion list. -- Steve