Genode Scheduling TrustZone Demo

[Stefan Kalkowski]

Hi Stefan,

On 07/15/2016 04:43 PM, Stefan Brenner wrote:
> Hi,
> 
> we are using inject_irq() from Martin Stein to inject interrupts into
> the normal world VM running Linux.
> 
> When measuring the time between issuing inject_irq() and actually
> arriving at the ISR in normal world (using CPU performance counters in
> CPU cycles granularity) we can see that this always requires at least 10
> million cycles, which is 10ms at 1Ghz and exactly what is defined as
> cpu_fill_ms in base-hw/src/core/include/kernel/configuration.h.
> 
> If we set cpu_fill_ms to 1, we can measure that it only requires 1
> million cycles. Apparently it is not possible to set values below 1
> (some assertion fails on compile).
> 
> Is there another option, probably a more elegant one, that allows the
> acceleration of interrupt injection?
> 

Normally, as long as no other component is runable and scheduled, you
should immediately receive the interrupt after calling inject_irq(...).
Are you sure that no other component is actively polling or otherwise
consuming a lot of cpu time?

Regards
Stefan

> Best, Stefan.
> 

-- 
Stefan Kalkowski
Genode Labs

https://github.com/skalk · http://genode.org/