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Re: [Xen-devel] [ARM] Native application design and discussion (I hope)

On Wed, 10 May 2017, Andrii Anisov wrote:
> On 10.05.17 12:56, George Dunlap wrote:
> > But the context here is that Andrii asked something about whether this
> > "EL0 App" functionality could be used to service Xen as well as a
> > domain.  You said it didn't make sense, and Dario (as I understand it)
> > was pointing out that we already did something similar with tasklets.
> > If there was a need to be able to "upload" user-specified routines that
> > would handle events generated by the hypervisor rather than events
> > generated by a guest, that would indeed be a possibility.  It would
> > essentially be the equivalent of a deprivileged, untrusted tasklet.

I just want to point out that the comparision with tasklets is not
helpful. Tasklets involve the idle vcpu, which we are trying to step away
from because it increases irq latency. Tasklets don't provide any
isolation. The context switch model for the idle vcpu and for EL0 apps
is different, thus it has a different cost.

I think we shouldn't mention tasklets in this thread any longer.

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