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Date: Thu, 23 Mar 2017 22:17:24 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Nicolas Pitre <nicolas.pitre@linaro.org>
cc: Daniel Lezcano <daniel.lezcano@linaro.org>,
        linux-kernel@vger.kernel.org, peterz@infradead.org, rafael@kernel.org,
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Subject: Re: [PATCH V8 2/3] irq: Track the interrupt timings
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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!