Re: [PATCH V8 2/3] irq: Track the interrupt timings

From	Thomas Gleixner <tglx@linutronix.de>
Newsgroups	linux.kernel
Subject	Re: [PATCH V8 2/3] irq: Track the interrupt timings
Date	2017-03-23 22:20 +0100
Message-ID	<toijg-88s-9@gated-at.bofh.it> (permalink)
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On Thu, 23 Mar 2017, Nicolas Pitre wrote:
> Is there a need for 64 bits of relative time stamps?
> And 32 bits of IRQ number?

No.

> I'd say that 48 bit time stamp and 16 bit IRQ number is way sufficient.
> Who cares if we mispredict an IRQ after 78 hours of idle time?
> 
> Hence:
> 
> 	u64 value = (ts << 16) | irq;

Excellent!

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[PATCH V8 2/3] irq: Track the interrupt timings Daniel Lezcano <daniel.lezcano@linaro.org> - 2017-03-23 18:50 +0100
  Re: [PATCH V8 2/3] irq: Track the interrupt timings Peter Zijlstra <peterz@infradead.org> - 2017-03-23 19:40 +0100
    Re: [PATCH V8 2/3] irq: Track the interrupt timings Nicolas Pitre <nicolas.pitre@linaro.org> - 2017-03-23 20:10 +0100
    Re: [PATCH V8 2/3] irq: Track the interrupt timings Daniel Lezcano <daniel.lezcano@linaro.org> - 2017-03-23 20:10 +0100
  Re: [PATCH V8 2/3] irq: Track the interrupt timings Nicolas Pitre <nicolas.pitre@linaro.org> - 2017-03-23 20:20 +0100
    Re: [PATCH V8 2/3] irq: Track the interrupt timings Thomas Gleixner <tglx@linutronix.de> - 2017-03-23 20:40 +0100
      Re: [PATCH V8 2/3] irq: Track the interrupt timings Nicolas Pitre <nicolas.pitre@linaro.org> - 2017-03-23 21:00 +0100
        Re: [PATCH V8 2/3] irq: Track the interrupt timings Thomas Gleixner <tglx@linutronix.de> - 2017-03-23 22:20 +0100

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