System clock died on e420r

Poul-Henning Kamp phk at
Tue Feb 15 00:39:44 PST 2005

In message <20050214230635.GA86332 at>, Kris Kennaway writes:

>On Mon, Feb 14, 2005 at 11:14:51PM +0100, Poul-Henning Kamp wrote:
>> If hardclock dies, timecounters (like much else) suffers.
>Surely, so why is it happening and how can it be fixed? :)
>jhb suspected there might be unserialized access to the time counter
>on sparc64.

As far as I know that timecounter is a single register so there is no
need for serialization.  It's only when the hardware requires you
to access multiple times/registers that you need to put locks around it.

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.

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