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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 D86E2C3F2CD for ; Mon, 23 Mar 2020 15:30:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AD30220735 for ; Mon, 23 Mar 2020 15:30:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584977444; bh=c/BmuNMOcm2EFTJiFoXTh1Vq5RGJMcdEbf3sn15wFTs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=BzAplZLnH8hcx5+UTZfTtiSLysYKY3A70kyis0vCYRnmGWBnpX1TA8upetpan0EIS yUYlLxWkS02QbsD+zwsQXrMagHk8EsIW1C1raRlhCROFA9UJLKzsOm7z9OBUelJNOo UwIdQre0SJ1t/fSyl3lYKkFTcTuHa+kfK/50nRQM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727277AbgCWPan (ORCPT ); Mon, 23 Mar 2020 11:30:43 -0400 Received: from mail.kernel.org ([198.145.29.99]:38732 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727176AbgCWPan (ORCPT ); Mon, 23 Mar 2020 11:30:43 -0400 Received: from localhost (lfbn-ncy-1-985-231.w90-101.abo.wanadoo.fr [90.101.63.231]) (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 46A99206C3; Mon, 23 Mar 2020 15:30:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584977442; bh=c/BmuNMOcm2EFTJiFoXTh1Vq5RGJMcdEbf3sn15wFTs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=UBZ7ZpqambbEgbhVe5WIcsu4UpeB10qjYzxwqgDEbXzE9XTQvb67iuULkW6UyWID5 f76NsPm8BzAZTrBUgF8MQHVNnUGchd/71x6SB9UUU0qDX3Q2yphEkGuu10cwduVZdL u0Y7keuyEj4nEEo8AB21fb/hLskbkCTsjntSPjPA= Date: Mon, 23 Mar 2020 16:30:40 +0100 From: Frederic Weisbecker To: Peter Zijlstra Cc: LKML , Sebastian Andrzej Siewior , "Paul E . McKenney" , Thomas Gleixner Subject: Re: [RFC PATCH 1/3] lockdep/irq: Be more strict about IRQ-threadable code end Message-ID: <20200323153039.GA5755@lenoir> References: <20200323033207.32370-1-frederic@kernel.org> <20200323033207.32370-2-frederic@kernel.org> <20200323135320.GJ2452@worktop.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200323135320.GJ2452@worktop.programming.kicks-ass.net> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 23, 2020 at 02:53:20PM +0100, Peter Zijlstra wrote: > On Mon, Mar 23, 2020 at 04:32:05AM +0100, Frederic Weisbecker wrote: > > --- a/kernel/irq/handle.c > > +++ b/kernel/irq/handle.c > > @@ -144,18 +144,24 @@ irqreturn_t __handle_irq_event_percpu(struct irq_desc *desc, unsigned int *flags > > > > for_each_action_of_desc(desc, action) { > > irqreturn_t res; > > + bool threadable; > > > > /* > > * If this IRQ would be threaded under force_irqthreads, mark it so. > > */ > > - if (irq_settings_can_thread(desc) && > > - !(action->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT))) > > + threadable = (irq_settings_can_thread(desc) && > > + !(action->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT))); > > + > > + if (threadable) > > trace_hardirq_threaded(); > > > > trace_irq_handler_entry(irq, action); > > res = action->handler(irq, action->dev_id); > > trace_irq_handler_exit(irq, action, res); > > > > + if (threadable) > > + trace_hardirq_unthreaded(); > > AFAICT this doesn't work for nested IRQ handlers. So current->hardirq_threaded should be a counter perhaps? > > > if (WARN_ONCE(!irqs_disabled(),"irq %u handler %pS enabled interrupts\n", > > irq, action->handler)) > > local_irq_disable(); > > -- > > 2.25.0 > >