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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 D06F0C433E0 for ; Mon, 15 Jun 2020 15:30:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9BCF92078A for ; Mon, 15 Jun 2020 15:30:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="t79Kc9yP" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730398AbgFOPa6 (ORCPT ); Mon, 15 Jun 2020 11:30:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47514 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729949AbgFOPa5 (ORCPT ); Mon, 15 Jun 2020 11:30:57 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B835EC061A0E for ; Mon, 15 Jun 2020 08:30:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=G5VsRueJ4myNT2iAEaTfoIaElgSbzxAH3MtfLJh9wMQ=; b=t79Kc9yP8bp/eUfdiADdoZSKco 8KU6BVeRlKrnhTtYslp4ygTNSzXxtmepKqCf0pGKqIJIBczqttxQQex3LBg68Gym77v0upVIq2g8s 5vHzf/MR3Vw0sf4nSjw+CfmwRX4Aoq1dy5jkK+2Q0Sgl//fbbt9ifi4sNWONZ73IdbJU+dfyq7Kdu gsIvVnzA/QpaY/gyY5D9fBpL9Foton3Ycp8rj6zy6K2JA1pgJwcc1jq8x/8540G9mzpjTcCmosROF a3mnZ10ZU+UQetWr65B0Q/VlvGJ9htbTPpZUBAf/x15KCXLTQS1kRQbZV3YcvUD3e9zSualbsNtjp B9LzjJPA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jkr4Y-0003tB-4g; Mon, 15 Jun 2020 15:30:54 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 8C6FF30081A; Mon, 15 Jun 2020 17:30:52 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 73096203C3762; Mon, 15 Jun 2020 17:30:52 +0200 (CEST) Date: Mon, 15 Jun 2020 17:30:52 +0200 From: Peter Zijlstra To: "Paul E. McKenney" Cc: tglx@linutronix.de, x86@kernel.org, elver@google.com, kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, will@kernel.org, dvyukov@google.com, glider@google.com, andreyknvl@google.com Subject: Re: [PATCH 2/9] rcu: Fixup noinstr warnings Message-ID: <20200615153052.GY2531@hirez.programming.kicks-ass.net> References: <20200603114014.152292216@infradead.org> <20200603114051.896465666@infradead.org> <20200603164600.GQ29598@paulmck-ThinkPad-P72> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200603164600.GQ29598@paulmck-ThinkPad-P72> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 03, 2020 at 09:46:00AM -0700, Paul E. McKenney wrote: > > // RCU is now watching. Better not be in an extended quiescent state! > > rcu_dynticks_task_trace_exit(); // After ->dynticks update! > > WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && > > !(seq & RCU_DYNTICK_CTRL_CTR)); > > if (seq & RCU_DYNTICK_CTRL_MASK) { > > - atomic_andnot(RCU_DYNTICK_CTRL_MASK, &rdp->dynticks); > > + arch_atomic_andnot(RCU_DYNTICK_CTRL_MASK, &rdp->dynticks); > > This one is gone in -rcu. I'm still seeing that in mainline, was that removal scheduled for next round? > > smp_mb__after_atomic(); /* _exit after clearing mask. */ > > } > > } What shall we do with this patch?