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Date: Thu, 22 Sep 2005 22:59:45 +0200
From: Dominik Brodowski <linux@dominikbrodowski.net>
To: Pierre Ossman <drzeus-list@drzeus.cx>
Cc: LKML <linux-kernel@vger.kernel.org>, Jesper Juhl <jesper.juhl@gmail.com>,
       john stultz <johnstul@us.ibm.com>
Subject: Re: [Fwd: sched_clock() has poor resolution]
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Hi,

On Thu, Sep 22, 2005 at 09:28:49AM +0200, Pierre Ossman wrote:
>  * Let sched_clock() follow the time source. Don't have it coupled to
> the TSC.
> 
>  * Init the TSC even though it isn't used for anything but sched_clock().

As pmtmr requires somewhat working TSCs, you can even use TSC if pmtmr is
used as a time source:

static int init_pmtmr(char* override)
...
        /* we use the TSC for delay_pmtmr, so make sure it exists */
        if (!cpu_has_tsc)
                return -ENODEV;
...

So at least for this case, sched_clock() can and should use TSC, not
jiffies, AFAICS.

Thanks,
	Dominik