From patchwork Sat Mar 21 11:26:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 11450977 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C4602139A for ; Sat, 21 Mar 2020 11:36:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AAF4920658 for ; Sat, 21 Mar 2020 11:36:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727071AbgCULgS (ORCPT ); Sat, 21 Mar 2020 07:36:18 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:38497 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728526AbgCULe6 (ORCPT ); Sat, 21 Mar 2020 07:34:58 -0400 Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jFcOb-0002LP-6D; Sat, 21 Mar 2020 12:34:29 +0100 Received: from nanos.tec.linutronix.de (localhost [IPv6:::1]) by nanos.tec.linutronix.de (Postfix) with ESMTP id E04FC1040C9; Sat, 21 Mar 2020 12:34:21 +0100 (CET) Message-Id: <20200321113242.534508206@linutronix.de> User-Agent: quilt/0.65 Date: Sat, 21 Mar 2020 12:26:02 +0100 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Sebastian Siewior , Linus Torvalds , Joel Fernandes , Oleg Nesterov , Davidlohr Bueso , Logan Gunthorpe , Bjorn Helgaas , Kurt Schwemmer , linux-pci@vger.kernel.org, Greg Kroah-Hartman , Felipe Balbi , linux-usb@vger.kernel.org, Kalle Valo , "David S. Miller" , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, Darren Hart , Andy Shevchenko , platform-driver-x86@vger.kernel.org, Zhang Rui , "Rafael J. Wysocki" , linux-pm@vger.kernel.org, Len Brown , linux-acpi@vger.kernel.org, kbuild test robot , Nick Hu , Greentime Hu , Vincent Chen , Guo Ren , linux-csky@vger.kernel.org, Brian Cain , linux-hexagon@vger.kernel.org, Tony Luck , Fenghua Yu , linux-ia64@vger.kernel.org, Michal Simek , Michael Ellerman , Arnd Bergmann , Geoff Levand , linuxppc-dev@lists.ozlabs.org, "Paul E . McKenney" , Jonathan Corbet , Randy Dunlap , Davidlohr Bueso Subject: [patch V3 18/20] lockdep: Add hrtimer context tracing bits References: <20200321112544.878032781@linutronix.de> MIME-Version: 1.0 Content-transfer-encoding: 8-bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org From: Sebastian Andrzej Siewior Set current->irq_config = 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 Signed-off-by: Thomas Gleixner --- 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(-) --- 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 = 1; \ + } while (0) + +# define lockdep_hrtimer_exit(__hrtimer) \ + do { \ + if (!__hrtimer->is_hard) \ + current->irq_config = 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 #if defined(CONFIG_IRQSOFF_TRACER) || \ --- 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 #ifdef CONFIG_LOCKDEP --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -3759,7 +3759,7 @@ static int check_wait_context(struct tas /* * Check if force_irqthreads will run us threaded. */ - if (curr->hardirq_threaded) + if (curr->hardirq_threaded || curr->irq_config) curr_inner = LD_WAIT_CONFIG; else curr_inner = LD_WAIT_SPIN; --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -1404,7 +1404,7 @@ static void __hrtimer_init(struct hrtime base = softtimer ? HRTIMER_MAX_CLOCK_BASES / 2 : 0; base += hrtimer_clockid_to_base(clock_id); timer->is_soft = softtimer; - timer->is_hard = !softtimer; + timer->is_hard = !!(mode & HRTIMER_MODE_HARD); timer->base = &cpu_base->clock_base[base]; timerqueue_init(&timer->node); } @@ -1514,7 +1514,11 @@ static void __run_hrtimer(struct hrtimer */ raw_spin_unlock_irqrestore(&cpu_base->lock, flags); trace_hrtimer_expire_entry(timer, now); + lockdep_hrtimer_enter(timer); + restart = fn(timer); + + lockdep_hrtimer_exit(timer); trace_hrtimer_expire_exit(timer); raw_spin_lock_irq(&cpu_base->lock);