From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.fraser@eu.citrix.com>
Subject: Re: [PATCH] Adjust time init sequence
Date: Thu, 11 Dec 2008 00:44:44 +0000
Message-ID: <C56612FC.2011A%keir.fraser@eu.citrix.com>
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To: "Tian, Kevin" <kevin.tian@intel.com>, "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>
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On 11/12/2008 00:23, "Tian, Kevin" <kevin.tian@intel.com> wrote:

>> Is it really safe to use NOW() before init_percpu_time()? Seems dodgy.
> 
> Where did you mean by using NOW before init_percpu_time?
> I moved do_settime earlier but with a zero system stamp now
> which matches the line behind to init stime_platform_time to zero.
> To me there's no difference to initialize wallclock at zero point
> or sometime after with a NOW() drift, which should cause similar
> result to wc_sec/wc_nsec.

init_platform_time() -> plt_overflow() -> NOW()

Perhaps the above is safe though? Will NOW() return zero for an
uninitialised per-cpu time sstructure (since stime_local_stamp and tsc_scale
are both zero)?

 -- Keir