On 12/04/2017 09:29 PM, Ran Shalit wrote: >> Stress runs a busy loop in user-space, hence the preempt/irqs are >> always enabled. > I understand the comments that comes later, but not this one above. > Can you please explain? > A "latency" you see on cyclictest is a side effect of either IRQs being masked, or the preemption being disabled. However, a process always returns to user-space with both interrupts and preemption enabled. So, a task in user-space will not cause latencies. As stress runs a busy loop in user-space... it will not cause latencies. -- Daniel -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
