Re: [RFC PATCH 1/3] Unified trace buffer

[Linus Torvalds]

On Thu, 25 Sep 2008, Steven Rostedt wrote:
> 
> The one thing that seemed to me most apparent from talking to people
> at LPC, is that they want a simple ring buffer API. If every tracer that
> uses this must come up with its own time keeping management, I don't think
> this will be used at all (except by those that are maintaining tracers
> now).

No, no.

The timestamp code is all in the ring buffer code. That was why I refused 
to have the layering without it.

And hell no, nobody should *ever* read the "tsc_delta" fields etc. Those 
are entirely internal to the buffering. If any user _ever_ reads or writes 
those on its own, it's a bug, plain and simple.

So when you read trace events, you should get the event data and the 
timestamp from the trace buffer routines. Nobody should ever even _see_ 
the internal trace buffer implementation!

			Linus
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