Re: [PATCH RT v2] x86/mce: Defer mce wakeups to threads for PREEMPT_RT

Sebastian Andrzej Siewior
2013-04-26T08:41:46Z

* Steven Rostedt | 2013-04-11 14:33:34 [-0400]:

>As wait queue locks are notorious for long hold times, we can not
>convert them to raw_spin_locks without causing issues with -rt. But
>Thomas has created a "simple-wait" structure that uses raw spin locks
>which may have been a good fit.
>
>Unfortunately, wait queues are not the only issue, as the mce_notify_irq
>also does a schedule_work(), which grabs the workqueue spin locks that
>have the exact same issue.

mce_notify_irq() can use simple_waitqueue, no?
The other issue is that mce_report_event() is scheduling a per-cpu
workqueue (mce_schedule_work) in case of a memory fault. This has the
same issue.

Sebastian