Messages in this thread | | | Date | Sat, 11 Jun 2005 18:31:07 -0400 | From | Karim Yaghmour <> | Subject | Re: PREEMPT_RT vs ADEOS: the numbers, part 1 |
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Ingo Molnar wrote: > how were interrupt response times measured, precisely? What did the > target (measured) system have to do to respond to an interrupt? Did you > use the RTC to measure IRQ latencies?
The logger used two TSC values. One prior to shooting the interrupt to the target, and one when receiving the response. Responding to an interrupt meant that a driver was hooked to the target's parallel port interrupt and simply acted by toggling an output pin on the parallel port, which in turn was hooked onto the logger's parallel port in a similar fashion. We'll post the code for all components (both logger and target) for everyone to review. There's no validity in any tests if others can't analyze/criticize/ duplicate.
Karim -- Author, Speaker, Developer, Consultant Pushing Embedded and Real-Time Linux Systems Beyond the Limits http://www.opersys.com || karim@opersys.com || 1-866-677-4546 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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