* Mike Galbraith | 2013-12-26 11:03:32 [+0100]:
>On Wed, 2013-12-25 at 04:07 +0100, Mike Galbraith wrote:
>> On Tue, 2013-12-24 at 11:36 -0800, Paul E. McKenney wrote:
>
>> > 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(+)
So I had rtmutex-take-the-waiter-lock-with-irqs-off.patch in my queue
which took the waiter lock with irqs off. This should be the same thing
you try do here.
>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();
> }
and this should be fixed differently. Since we come from a thread and
check "is current running" but by current we mean a user task and not a
kernel thread.
>
> static DEFINE_PER_CPU(struct irq_work, nohz_full_kick_work) = {
>
Sebastian
--
To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
