On Wed, 2013-12-25 at 04:07 +0100, Mike Galbraith wrote:

quoted

On Tue, 2013-12-24 at 11:36 -0800, Paul E. McKenney wrote: 

quoted

quoted

So which code do you think deserves the big lump of coal?  ;-)

Sebastian's NO_HZ_FULL locking fixes.

Whack-a-mole hasn't yet dug up any new moles.

---
kernel/timer.c |    4 ++++
1 file changed, 4 insertions(+)

Index: linux-2.6/kernel/timer.c
===================================================================

--- linux-2.6.orig/kernel/timer.c
+++ linux-2.6/kernel/timer.c

@@ -764,7 +764,9 @@ __mod_timer(struct timer_list *timer, un

	timer_stats_timer_set_start_info(timer);
	BUG_ON(!timer->function);

+	local_irq_disable_rt();
	base = lock_timer_base(timer, &flags);
+	local_irq_enable_rt();

	ret = detach_if_pending(timer, base, false);
	if (!ret && pending_only)

@@ -1198,7 +1200,9 @@ static inline void __run_timers(struct t

{
	struct timer_list *timer;

+	local_irq_disable_rt();
	spin_lock_irq(&base->lock);
+	local_irq_enable_rt();
	while (time_after_eq(jiffies, base->timer_jiffies)) {
		struct list_head work_list;
		struct list_head *head = &work_list;
---
kernel/time/tick-sched.c |    2 ++
1 file changed, 2 insertions(+)

Index: linux-2.6/kernel/time/tick-sched.c
===================================================================

--- linux-2.6.orig/kernel/time/tick-sched.c
+++ linux-2.6/kernel/time/tick-sched.c

@@ -216,7 +216,9 @@ void __tick_nohz_full_check(void)

static void nohz_full_kick_work_func(struct irq_work *work)
{
+	local_irq_disable_rt();
	__tick_nohz_full_check();
+	local_irq_enable_rt();
}