Messages in this thread | | | Date | Fri, 19 Feb 2021 23:08:08 -0800 | From | Brad Boyer <> | Subject | Re: [RFC] IRQ handlers run with some high-priority interrupts(not NMI) enabled on some platform |
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On Sat, Feb 20, 2021 at 05:32:30PM +1100, Finn Thain wrote: > Nope. Interrupt priority masking is there to place an upper bound > interrupt latency. That's why this feature is shipping in contemporary > hardware (e.g. ARM GIC). If you care about real time workloads on arm64, > that may interest you.
I don't know if it's still true today, but in the past there was a very noticeable difference in timer stability between the 68k macintosh models with the timer interrupt at IPL 1 as compared to the models where the timer interrupt was at IPL 6. The ability to preempt the other interrupt handlers made the difference between a usable clock and one that was pretty unreliable.
Brad Boyer flar@allandria.com
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