tegrakernel/kernel/kernel-4.9/rt-patches/0159-softirq-wake-the-timer...

78 lines
2.3 KiB
Diff

From bfa45fec12076a38b29f2e3ab80410a1ae8ba10b Mon Sep 17 00:00:00 2001
From: Mike Galbraith <efault@gmx.de>
Date: Fri, 20 Jan 2017 18:10:20 +0100
Subject: [PATCH 159/365] softirq: wake the timer softirq if needed
The irq-exit path only checks the "normal"-softirq thread if it is
running and ignores the state of the "timer"-softirq thread. It is possible
that the timer-softirq thread is and has work pending which leads to the
following warning:
[ 84.087571] NOHZ: local_softirq_pending 02
[ 84.087593] NOHZ: local_softirq_pending 02
[ 84.087598] NOHZ: local_softirq_pending 02
[ 84.087904] NOHZ: local_softirq_pending 02
[ 84.088526] NOHZ: local_softirq_pending 02
[ 84.088899] NOHZ: local_softirq_pending 02
[ 84.089463] NOHZ: local_softirq_pending 02
[ 115.013470] NOHZ: local_softirq_pending 02
[ 115.013601] NOHZ: local_softirq_pending 02
[ 115.013709] NOHZ: local_softirq_pending 02
This was introduced during the timer-softirq split.
Cc: stable-rt@vger.kernel.org
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
kernel/softirq.c | 9 +++------
1 file changed, 3 insertions(+), 6 deletions(-)
diff --git a/kernel/softirq.c b/kernel/softirq.c
index af0b78e44bb0..b5f185b89857 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -206,6 +206,7 @@ static void handle_softirq(unsigned int vec_nr)
}
}
+#ifndef CONFIG_PREEMPT_RT_FULL
/*
* If ksoftirqd is scheduled, we do not want to process pending softirqs
* right now. Let ksoftirqd handle this at its own rate, to get fairness,
@@ -221,7 +222,6 @@ static bool ksoftirqd_running(unsigned long pending)
return tsk && (tsk->state == TASK_RUNNING);
}
-#ifndef CONFIG_PREEMPT_RT_FULL
static inline int ksoftirqd_softirq_pending(void)
{
return local_softirq_pending();
@@ -777,14 +777,10 @@ void irq_enter(void)
static inline void invoke_softirq(void)
{
-#ifdef CONFIG_PREEMPT_RT_FULL
- unsigned long flags;
-#endif
-
+#ifndef CONFIG_PREEMPT_RT_FULL
if (ksoftirqd_running(local_softirq_pending()))
return;
-#ifndef CONFIG_PREEMPT_RT_FULL
if (!force_irqthreads) {
#ifdef CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK
/*
@@ -805,6 +801,7 @@ static inline void invoke_softirq(void)
wakeup_softirqd();
}
#else /* PREEMPT_RT_FULL */
+ unsigned long flags;
local_irq_save(flags);
if (__this_cpu_read(ksoftirqd) &&
--
2.28.0