From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932434AbeDWTQp (ORCPT ); Mon, 23 Apr 2018 15:16:45 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:58567 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932175AbeDWTQn (ORCPT ); Mon, 23 Apr 2018 15:16:43 -0400 From: Sebastian Andrzej Siewior To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Thomas Gleixner , Sebastian Andrzej Siewior Subject: [PATCH] stop_machine: Use raw spinlocks Date: Mon, 23 Apr 2018 21:16:35 +0200 Message-Id: <20180423191635.6014-1-bigeasy@linutronix.de> X-Mailer: git-send-email 2.17.0 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Thomas Gleixner Use raw-locks in stop_machine() to allow locking in irq-off and preempt-disabled regions on -RT. Signed-off-by: Thomas Gleixner [bigeasy: update patch description.] Signed-off-by: Sebastian Andrzej Siewior --- kernel/stop_machine.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index b7591261652d..c25ba18274fb 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -36,7 +36,7 @@ struct cpu_stop_done { struct cpu_stopper { struct task_struct *thread; =20 - spinlock_t lock; + raw_spinlock_t lock; bool enabled; /* is this stopper enabled? */ struct list_head works; /* list of pending works */ =20 @@ -78,13 +78,13 @@ static bool cpu_stop_queue_work(unsigned int cpu, struc= t cpu_stop_work *work) unsigned long flags; bool enabled; =20 - spin_lock_irqsave(&stopper->lock, flags); + raw_spin_lock_irqsave(&stopper->lock, flags); enabled =3D stopper->enabled; if (enabled) __cpu_stop_queue_work(stopper, work); else if (work->done) cpu_stop_signal_done(work->done); - spin_unlock_irqrestore(&stopper->lock, flags); + raw_spin_unlock_irqrestore(&stopper->lock, flags); =20 return enabled; } @@ -231,8 +231,8 @@ static int cpu_stop_queue_two_works(int cpu1, struct cp= u_stop_work *work1, struct cpu_stopper *stopper2 =3D per_cpu_ptr(&cpu_stopper, cpu2); int err; retry: - spin_lock_irq(&stopper1->lock); - spin_lock_nested(&stopper2->lock, SINGLE_DEPTH_NESTING); + raw_spin_lock_irq(&stopper1->lock); + raw_spin_lock_nested(&stopper2->lock, SINGLE_DEPTH_NESTING); =20 err =3D -ENOENT; if (!stopper1->enabled || !stopper2->enabled) @@ -255,8 +255,8 @@ static int cpu_stop_queue_two_works(int cpu1, struct cp= u_stop_work *work1, __cpu_stop_queue_work(stopper1, work1); __cpu_stop_queue_work(stopper2, work2); unlock: - spin_unlock(&stopper2->lock); - spin_unlock_irq(&stopper1->lock); + raw_spin_unlock(&stopper2->lock); + raw_spin_unlock_irq(&stopper1->lock); =20 if (unlikely(err =3D=3D -EDEADLK)) { while (stop_cpus_in_progress) @@ -448,9 +448,9 @@ static int cpu_stop_should_run(unsigned int cpu) unsigned long flags; int run; =20 - spin_lock_irqsave(&stopper->lock, flags); + raw_spin_lock_irqsave(&stopper->lock, flags); run =3D !list_empty(&stopper->works); - spin_unlock_irqrestore(&stopper->lock, flags); + raw_spin_unlock_irqrestore(&stopper->lock, flags); return run; } =20 @@ -461,13 +461,13 @@ static void cpu_stopper_thread(unsigned int cpu) =20 repeat: work =3D NULL; - spin_lock_irq(&stopper->lock); + raw_spin_lock_irq(&stopper->lock); if (!list_empty(&stopper->works)) { work =3D list_first_entry(&stopper->works, struct cpu_stop_work, list); list_del_init(&work->list); } - spin_unlock_irq(&stopper->lock); + raw_spin_unlock_irq(&stopper->lock); =20 if (work) { cpu_stop_fn_t fn =3D work->fn; @@ -541,7 +541,7 @@ static int __init cpu_stop_init(void) for_each_possible_cpu(cpu) { struct cpu_stopper *stopper =3D &per_cpu(cpu_stopper, cpu); =20 - spin_lock_init(&stopper->lock); + raw_spin_lock_init(&stopper->lock); INIT_LIST_HEAD(&stopper->works); } =20 --=20 2.17.0