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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 9A2FCC4CECE for ; Fri, 13 Mar 2020 17:47:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7DD58206E2 for ; Fri, 13 Mar 2020 17:47:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727183AbgCMRr1 (ORCPT ); Fri, 13 Mar 2020 13:47:27 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:47725 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727131AbgCMRrX (ORCPT ); Fri, 13 Mar 2020 13:47:23 -0400 Received: from localhost ([127.0.0.1] helo=flow.W.breakpoint.cc) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1jCoP2-00017r-Tg; Fri, 13 Mar 2020 18:47:21 +0100 From: Sebastian Andrzej Siewior To: linux-kernel@vger.kernel.org Cc: Peter Zijlstra , Ingo Molnar , Will Deacon , "Paul E . McKenney" , Joel Fernandes , Steven Rostedt , Linus Torvalds , Thomas Gleixner , Sebastian Andrzej Siewior Subject: [PATCH 7/9] lockdep: Add hrtimer context tracing bits Date: Fri, 13 Mar 2020 18:46:59 +0100 Message-Id: <20200313174701.148376-8-bigeasy@linutronix.de> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200313174701.148376-1-bigeasy@linutronix.de> References: <20200313174701.148376-1-bigeasy@linutronix.de> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Set current->irq_config =3D 1 for hrtimers which are not marked to expire in hard interrupt context during hrtimer_init(). These timers will expire in softirq context on PREEMPT_RT. Setting this allows lockdep to differentiate these timers. If a timer is marked to expire in hard interrupt context then the timer callback is not supposed to acquire a regular spinlock instead of a raw_spinlock in the expiry callback. Signed-off-by: Sebastian Andrzej Siewior --- include/linux/irqflags.h | 15 +++++++++++++++ include/linux/sched.h | 1 + kernel/locking/lockdep.c | 2 +- kernel/time/hrtimer.c | 6 +++++- 4 files changed, 22 insertions(+), 2 deletions(-) diff --git a/include/linux/irqflags.h b/include/linux/irqflags.h index fdaf28601cbe1..9c17f9c827aac 100644 --- a/include/linux/irqflags.h +++ b/include/linux/irqflags.h @@ -56,6 +56,19 @@ do { \ do { \ current->softirq_context--; \ } while (0) + +# define lockdep_hrtimer_enter(__hrtimer) \ + do { \ + if (!__hrtimer->is_hard) \ + current->irq_config =3D 1; \ + } while (0) + +# define lockdep_hrtimer_exit(__hrtimer) \ + do { \ + if (!__hrtimer->is_hard) \ + current->irq_config =3D 0; \ + } while (0) + #else # define trace_hardirqs_on() do { } while (0) # define trace_hardirqs_off() do { } while (0) @@ -68,6 +81,8 @@ do { \ # define trace_hardirq_exit() do { } while (0) # define lockdep_softirq_enter() do { } while (0) # define lockdep_softirq_exit() do { } while (0) +# define lockdep_hrtimer_enter(__hrtimer) do { } while (0) +# define lockdep_hrtimer_exit(__hrtimer) do { } while (0) #endif =20 #if defined(CONFIG_IRQSOFF_TRACER) || \ diff --git a/include/linux/sched.h b/include/linux/sched.h index 4d3b9ecce0742..933914cdf2197 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -983,6 +983,7 @@ struct task_struct { unsigned int softirq_enable_event; int softirqs_enabled; int softirq_context; + int irq_config; #endif =20 #ifdef CONFIG_LOCKDEP diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 4a9abf8bd9d15..df74531fd9f85 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -3879,7 +3879,7 @@ static int check_wait_context(struct task_struct *cur= r, struct held_lock *next) /* * Check if force_irqthreads will run us threaded. */ - if (curr->hardirq_threaded) + if (curr->hardirq_threaded || curr->irq_config) curr_inner =3D LD_WAIT_CONFIG; else curr_inner =3D LD_WAIT_SPIN; diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 3a609e7344f3d..8cce72501aea5 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -1404,7 +1404,7 @@ static void __hrtimer_init(struct hrtimer *timer, clo= ckid_t clock_id, base =3D softtimer ? HRTIMER_MAX_CLOCK_BASES / 2 : 0; base +=3D hrtimer_clockid_to_base(clock_id); timer->is_soft =3D softtimer; - timer->is_hard =3D !softtimer; + timer->is_hard =3D !!(mode & HRTIMER_MODE_HARD); timer->base =3D &cpu_base->clock_base[base]; timerqueue_init(&timer->node); } @@ -1514,7 +1514,11 @@ static void __run_hrtimer(struct hrtimer_cpu_base *c= pu_base, */ raw_spin_unlock_irqrestore(&cpu_base->lock, flags); trace_hrtimer_expire_entry(timer, now); + lockdep_hrtimer_enter(timer); + restart =3D fn(timer); + + lockdep_hrtimer_exit(timer); trace_hrtimer_expire_exit(timer); raw_spin_lock_irq(&cpu_base->lock); =20 --=20 2.25.1