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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,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 EAD80C4CECF for ; Mon, 23 Sep 2019 16:59:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CA3E720882 for ; Mon, 23 Sep 2019 16:59:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2440026AbfIWQ72 (ORCPT ); Mon, 23 Sep 2019 12:59:28 -0400 Received: from mx1.redhat.com ([209.132.183.28]:53354 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390600AbfIWQ72 (ORCPT ); Mon, 23 Sep 2019 12:59:28 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8F9EE87521F; Mon, 23 Sep 2019 16:59:27 +0000 (UTC) Received: from ovpn-117-172.phx2.redhat.com (ovpn-117-172.phx2.redhat.com [10.3.117.172]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4C33F60852; Mon, 23 Sep 2019 16:59:24 +0000 (UTC) Message-ID: <404575720cf24765e66020f15ce75352f08a0ddb.camel@redhat.com> Subject: Re: [PATCH RT v3 3/5] sched: migrate_dis/enable: Use rt_invol_sleep From: Scott Wood To: Sebastian Andrzej Siewior Cc: linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org, "Paul E . McKenney" , Joel Fernandes , Thomas Gleixner , Steven Rostedt , Peter Zijlstra , Juri Lelli , Clark Williams Date: Mon, 23 Sep 2019 11:59:23 -0500 In-Reply-To: <779eddcc937941e65659a11b1867c6623a2c8890.camel@redhat.com> References: <20190911165729.11178-1-swood@redhat.com> <20190911165729.11178-4-swood@redhat.com> <20190917075943.qsaakyent4dxjkq4@linutronix.de> <779eddcc937941e65659a11b1867c6623a2c8890.camel@redhat.com> Organization: Red Hat Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.30.5 (3.30.5-1.fc29) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.68]); Mon, 23 Sep 2019 16:59:27 +0000 (UTC) Sender: linux-rt-users-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rt-users@vger.kernel.org On Tue, 2019-09-17 at 09:06 -0500, Scott Wood wrote: > On Tue, 2019-09-17 at 09:59 +0200, Sebastian Andrzej Siewior wrote: > > On 2019-09-11 17:57:27 [+0100], Scott Wood wrote: > > > diff --git a/kernel/cpu.c b/kernel/cpu.c > > > index 885a195dfbe0..32c6175b63b6 100644 > > > --- a/kernel/cpu.c > > > +++ b/kernel/cpu.c > > > @@ -308,7 +308,9 @@ void pin_current_cpu(void) > > > preempt_lazy_enable(); > > > preempt_enable(); > > > > > > + rt_invol_sleep_inc(); > > > __read_rt_lock(cpuhp_pin); > > > + rt_invol_sleep_dec(); > > > > > > preempt_disable(); > > > preempt_lazy_disable(); > > > > I understand the other one. But now looking at it, both end up in > > rt_spin_lock_slowlock_locked() which would be the proper place to do > > that annotation. Okay. > > FWIW, if my lazy migrate patchset is accepted, then there will be no users > of __read_rt_lock() outside rwlock-rt.c and it'll be moot. I missed the "both" -- which is the "other one" that ends up in rt_spin_lock_slowlock_locked()? stop_one_cpu() doesn't... -Scott