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Date: Mon, 28 Aug 2017 17:13:58 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Pasha Tatashin <pasha.tatashin@oracle.com>
cc: x86@kernel.org, linux-kernel@vger.kernel.org, mingo@redhat.com,
        peterz@infradead.org, hpa@zytor.com, douly.fnst@cn.fujitsu.com
Subject: Re: [PATCH v5 1/2] sched/clock: interface to allow timestamps early
 in boot
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On Mon, 28 Aug 2017, Pasha Tatashin wrote:
> This makes sense. Changing order in timekeeping_init(void) should take care of
> this:
> 
> Change to:
> 
> void __init timekeeping_init(void)
> {
> 	/*
> 	 * We must determine boot timestamp before getting current  	
> 	 * persistent clock value, because implementation of
> 	 * read_boot_clock64() might also call the persistent
> 	 * clock, and a leap second may occur.
> 	 */
> 
> 	read_boot_clock64(&boot);
> 	...
> 	read_persistent_clock64(&now);

No. That's the same crap just the other way round.

s390 can do that, because the boot timestamp is correlated with the
persistent clock. Your's not so much.

Thanks,

	tglx