Messages in this thread | | | Subject | Re: bisected: 'perf top' causing soft lockups under Xen | From | Peter Zijlstra <> | Date | Wed, 15 Feb 2012 10:25:44 +0100 |
| |
On Wed, 2012-02-15 at 00:57 -0800, Steven Noonan wrote: > It seems to me that there are two options for fixing this, but I'm > probably lacking the necessary context (or experience with Xen). Either: > > - The patch provided by Ben needs to have additional work to specially > handle IRQ_WORK_VECTOR, since it seems to be a special case where > there's no event channel attached for it. Perhaps adding an event > channel for this is the fix? Seems high-overhead, but I lack a good > understanding of how interrupts are handled in Xen.
So that's a self-IPI, is Xen failing to implement this?
> or > > - Perf needs to be "enlightened" about Xen and avoid sending an IPI in > the first place.
Uhm, no. If anything Xen should simply not implement arch_irq_work_raise(). The callbacks are then ran from the timer interrupt.
| |