From da619e2c9a6272d7e6507460e3f38d20fbaa7393 Mon Sep 17 00:00:00 2001
Message-Id: <da619e2c9a6272d7e6507460e3f38d20fbaa7393.1599166690.git.zanussi@kernel.org>
In-Reply-To: <56457dc415803c8abc5acb513ada877a79596f05.1599166690.git.zanussi@kernel.org>
References: <56457dc415803c8abc5acb513ada877a79596f05.1599166690.git.zanussi@kernel.org>
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Wed, 15 Nov 2017 17:29:51 +0100
Subject: [PATCH 097/333] time/hrtimer: avoid schedule_work() with interrupts
 disabled
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.142-rt63.tar.xz

The NOHZ code tries to schedule a workqueue with interrupts disabled.
Since this does not work -RT I am switching it to swork instead.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 kernel/time/timer.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index ecc23d2c21a9..753b75751f0a 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -218,8 +218,7 @@ static DEFINE_PER_CPU(struct timer_base, timer_bases[NR_BASES]);
 static DEFINE_STATIC_KEY_FALSE(timers_nohz_active);
 static DEFINE_MUTEX(timer_keys_mutex);
 
-static void timer_update_keys(struct work_struct *work);
-static DECLARE_WORK(timer_update_work, timer_update_keys);
+static struct swork_event timer_update_swork;
 
 #ifdef CONFIG_SMP
 unsigned int sysctl_timer_migration = 1;
@@ -237,7 +236,7 @@ static void timers_update_migration(void)
 static inline void timers_update_migration(void) { }
 #endif /* !CONFIG_SMP */
 
-static void timer_update_keys(struct work_struct *work)
+static void timer_update_keys(struct swork_event *event)
 {
 	mutex_lock(&timer_keys_mutex);
 	timers_update_migration();
@@ -247,9 +246,17 @@ static void timer_update_keys(struct work_struct *work)
 
 void timers_update_nohz(void)
 {
-	schedule_work(&timer_update_work);
+	swork_queue(&timer_update_swork);
 }
 
+static __init int hrtimer_init_thread(void)
+{
+	WARN_ON(swork_get());
+	INIT_SWORK(&timer_update_swork, timer_update_keys);
+	return 0;
+}
+early_initcall(hrtimer_init_thread);
+
 int timer_migration_handler(struct ctl_table *table, int write,
 			    void __user *buffer, size_t *lenp,
 			    loff_t *ppos)
-- 
2.17.1

