Subject: Re: [PATCH] update clocksource raw_time in timekeeping_suspend
From: john stultz <johnstul@us.ibm.com>
To: ye janboe <janboe.ye@gmail.com>
Cc: Yong Zhang <yong.zhang0@gmail.com>, zippel@linux-m68k.org,
       akpm@linux-foundation.org, mingo@elte.hu,
       linux-kernel <linux-kernel@vger.kernel.org>
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Date: Fri, 11 Sep 2009 11:09:04 -0700
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On Fri, 2009-09-11 at 11:35 +0800, ye janboe wrote:
> So CLOCK_MONOTONIC_RAW is not suitable for getting real hw time which
> includes sleep time.

Hmm.. This is sort of an odd request. 

The clocksource hardware counters stop in during suspend, so any "real
hw time that includes sleep" is likely to be combined from different
sources (with slightly different drifts), so I'm not sure why
CLOCK_MONOTONIC_RAW would be preferred over CLOCK_MONOTONIC?


> Is there other timer suitable for this?

Maybe the CMOS / RTC?  Would that suffice?

Could you maybe provide more details about why you need this? Maybe
better understanding your needs would help point to a solution.

thanks
-john


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