dynamic function tracing

[Arjan van de Ven <arjan@infradead.org>]

Hi,

I like the new function trace format with the {}'s a lot.. but I would
like to use it in a way I don't think would work with dynamic tracing.

What I would like to do (read: usecase) is mark a function as
interesting (because it has some performance issue or whatever),
and then I want to get all functions it calls (recursive) traced
automatically for the duration of that function.

This might be implementable by, on hitting the function to trace,
patching all trace points with a function that checks if it's this
thread (eg this "current"), and if so, traces the call. 
I realize it's not going to be super cheap, so it needs to be one-shot,
but it'll form a really strong usecase in practice...


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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