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From: "Martin Bligh" <mbligh@google.com>
To: "Masami Hiramatsu" <mhiramat@redhat.com>
Subject: Re: Unified tracing buffer
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>> I think we came up with a way to approximate this, using a callback every
>> ms or so as the higher order bits, and a sequential counter in the lower
>> order for those broken platforms.
>
> Sure, that will work.

OK, that'd fix 99% of it, even if we only get time within 1ms or so (but still
good ordering).

>> But perhaps it would be better if we started with a discussion of which
>> platforms can't do global timestamps, and why not? I know some of them
>> are fixable, but perhaps not all.
>
> For example, my laptop (this machine/Core2Duo) doesn't return correct TSC. :-(

Can you define incorrect for me (in this case)?

We had similar problems with some AMD platforms that we can fix by syncing
the TSCs on exit_idle, etc.