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Date:   Tue, 17 Jul 2018 10:40:12 +0200 (CEST)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Baolin Wang <baolin.wang@linaro.org>
cc:     john.stultz@linaro.org, sboyd@kernel.org, arnd@arndb.de,
        broonie@kernel.org, daniel.lezcano@linaro.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] time: Introduce one suspend clocksource to compensate
 the suspend time
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References: <c233469f487d9e187de3fdaf79db4e1a7ca7486d.1531812082.git.baolin.wang@linaro.org>
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On Tue, 17 Jul 2018, Baolin Wang wrote:
> On some hardware with multiple clocksources, we have coarse grained
> clocksources that support the CLOCK_SOURCE_SUSPEND_NONSTOP flag, but
> which are less than ideal for timekeeping whereas other clocksources
> can be better candidates but halt on suspend.
> 
> Currently, the timekeeping core only supports timing suspend using
> CLOCK_SOURCE_SUSPEND_NONSTOP clocksources if that clocksource is the
> current clocksource for timekeeping.
> 
> As a result, some architectures try to implement read_persistent_clock64()
> using those non-stop clocksources, but isn't really ideal, which will
> introduce more duplicate code. To fix this, provide logic to allow a
> registered SUSPEND_NONSTOP clocksource, which isn't the current
> clocksource, to be used to calculate the suspend time.
> 
> Suggested-by: Thomas Gleixner <tglx@linutronix.de>
> Signed-off-by: Baolin Wang <baolin.wang@linaro.org>

Well done!

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>