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=unavailable 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 9876FC7618B for ; Sat, 27 Jul 2019 05:57:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7A1EC20869 for ; Sat, 27 Jul 2019 05:57:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728351AbfG0F4q (ORCPT ); Sat, 27 Jul 2019 01:56:46 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49184 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727246AbfG0F4p (ORCPT ); Sat, 27 Jul 2019 01:56:45 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 7B6333E2CB; Sat, 27 Jul 2019 05:56:45 +0000 (UTC) Received: from t460p.redhat.com (ovpn-116-73.phx2.redhat.com [10.3.116.73]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7D3E719C79; Sat, 27 Jul 2019 05:56:44 +0000 (UTC) From: Scott Wood To: Sebastian Andrzej Siewior Cc: Thomas Gleixner , Steven Rostedt , Peter Zijlstra , Juri Lelli , Daniel Bristot de Oliveira , Clark Williams , linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org, Scott Wood Subject: [PATCH RT 1/8] sched: migrate_enable: Use sleeping_lock to indicate involuntary sleep Date: Sat, 27 Jul 2019 00:56:31 -0500 Message-Id: <20190727055638.20443-2-swood@redhat.com> In-Reply-To: <20190727055638.20443-1-swood@redhat.com> References: <20190727055638.20443-1-swood@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Sat, 27 Jul 2019 05:56:45 +0000 (UTC) Sender: linux-rt-users-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rt-users@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 4e218f8d8048..ad23ab939b35 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -673,7 +673,7 @@ struct task_struct { int migrate_disable_atomic; # endif #endif -#ifdef CONFIG_PREEMPT_RT_FULL +#ifdef CONFIG_PREEMPT_RT_BASE int sleeping_lock; #endif @@ -1873,7 +1873,7 @@ 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 23a54e4b649c..7a3aa085ce2c 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -292,7 +292,7 @@ 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 d3c6542b306f..c3407707e367 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -7405,7 +7405,9 @@ 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(); return; } } -- 1.8.3.1