From 09089db79859cbccccd8df95b034f36f7027efa6 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Wed, 6 Oct 2021 13:18:52 +0200 Subject: irq_work: Also rcuwait for !IRQ_WORK_HARD_IRQ on PREEMPT_RT On PREEMPT_RT most items are processed as LAZY via softirq context. Avoid to spin-wait for them because irq_work_sync() could have higher priority and not allow the irq-work to be completed. Wait additionally for !IRQ_WORK_HARD_IRQ irq_work items on PREEMPT_RT. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20211006111852.1514359-5-bigeasy@linutronix.de --- kernel/irq_work.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'kernel/irq_work.c') diff --git a/kernel/irq_work.c b/kernel/irq_work.c index 90b6b56f92e9..f7df715ec28e 100644 --- a/kernel/irq_work.c +++ b/kernel/irq_work.c @@ -217,7 +217,8 @@ void irq_work_single(void *arg) */ (void)atomic_cmpxchg(&work->node.a_flags, flags, flags & ~IRQ_WORK_BUSY); - if (!arch_irq_work_has_interrupt()) + if ((IS_ENABLED(CONFIG_PREEMPT_RT) && !irq_work_is_hard(work)) || + !arch_irq_work_has_interrupt()) rcuwait_wake_up(&work->irqwait); } @@ -277,7 +278,8 @@ void irq_work_sync(struct irq_work *work) lockdep_assert_irqs_enabled(); might_sleep(); - if (!arch_irq_work_has_interrupt()) { + if ((IS_ENABLED(CONFIG_PREEMPT_RT) && !irq_work_is_hard(work)) || + !arch_irq_work_has_interrupt()) { rcuwait_wait_event(&work->irqwait, !irq_work_is_busy(work), TASK_UNINTERRUPTIBLE); return; -- cgit v1.2.3-59-g8ed1b