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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 E3202C46477 for ; Wed, 19 Jun 2019 01:19:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C6C8F2147A for ; Wed, 19 Jun 2019 01:19:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729868AbfFSBTP (ORCPT ); Tue, 18 Jun 2019 21:19:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44660 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729721AbfFSBTP (ORCPT ); Tue, 18 Jun 2019 21:19:15 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D92673082E71; Wed, 19 Jun 2019 01:19:14 +0000 (UTC) Received: from t460p.redhat.com (ovpn-117-83.phx2.redhat.com [10.3.117.83]) by smtp.corp.redhat.com (Postfix) with ESMTP id F1CE07D65A; Wed, 19 Jun 2019 01:19:13 +0000 (UTC) From: Scott Wood To: Sebastian Andrzej Siewior Cc: "Paul E. McKenney" , Peter Zijlstra , Steven Rostedt , Thomas Gleixner , Juri Lelli , Clark Williams , linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org, Scott Wood Subject: [PATCH RT 2/4] sched: migrate_enable: Use sleeping_lock to indicate involuntary sleep Date: Tue, 18 Jun 2019 20:19:06 -0500 Message-Id: <20190619011908.25026-3-swood@redhat.com> In-Reply-To: <20190619011908.25026-1-swood@redhat.com> References: <20190619011908.25026-1-swood@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.46]); Wed, 19 Jun 2019 01:19:14 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Without this, rcu_note_context_switch() will complain if an RCU read lock is held when migrate_enable() calls stop_one_cpu(). Signed-off-by: Scott Wood --- include/linux/sched.h | 4 ++-- kernel/rcu/tree_plugin.h | 2 +- kernel/sched/core.c | 2 ++ 3 files changed, 5 insertions(+), 3 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index e1ea2ea52feb..9b8334c24dad 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -681,7 +681,7 @@ struct task_struct { int migrate_disable_atomic; # endif #endif -#ifdef CONFIG_PREEMPT_RT_FULL +#ifdef CONFIG_PREEMPT_RT_BASE int sleeping_lock; #endif @@ -1870,7 +1870,7 @@ static __always_inline bool need_resched(void) return unlikely(tif_need_resched()); } -#ifdef CONFIG_PREEMPT_RT_FULL +#ifdef CONFIG_PREEMPT_RT_BASE static inline void sleeping_lock_inc(void) { current->sleeping_lock++; diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 4bac3e5ee1ab..5d63914b3687 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -311,7 +311,7 @@ void rcu_note_context_switch(bool preempt) barrier(); /* Avoid RCU read-side critical sections leaking down. */ trace_rcu_utilization(TPS("Start context switch")); lockdep_assert_irqs_disabled(); -#if defined(CONFIG_PREEMPT_RT_FULL) +#if defined(CONFIG_PREEMPT_RT_BASE) sleeping_l = t->sleeping_lock; #endif WARN_ON_ONCE(!preempt && t->rcu_read_lock_nesting > 0 && !sleeping_l); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index a8493ff60b67..fce7d574ab5b 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -7351,7 +7351,9 @@ void migrate_enable(void) unpin_current_cpu(); preempt_lazy_enable(); preempt_enable(); + sleeping_lock_inc(); stop_one_cpu(task_cpu(p), migration_cpu_stop, &arg); + sleeping_lock_dec(); tlb_migrate_finish(p->mm); return; -- 1.8.3.1