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Date: Mon, 6 Sep 2010 17:12:17 -0400
From: Christoph Hellwig <hch@infradead.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Christoph Hellwig <hch@infradead.org>,
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Subject: Re: [PATCHv11 2.6.36-rc2-tip 5/15]  5: uprobes: Uprobes
 (un)registration and exception handling.
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On Mon, Sep 06, 2010 at 11:06:08PM +0200, Peter Zijlstra wrote:
> > The other things is that perf currently only supports per-kernel pid
> > recording, while we'd really need per Posix process, which may contain
> > multiple threads for useful tracing of complex userspace applications.
> > I also suspect that this will fit the uprobes model much better given
> > that the probes will be in any given address space.
> 
> perf does report both:
> 
>          *      { u32                   pid, tid; } && PERF_SAMPLE_TID
> 
> the pid is the process id (thread group leader like) and tid is the
> task/thread id.

It records both, but I haven't found a way to only record samples
or trace things in a Posix Process.

E.g. perf record -p seems to be only per-thread, not per-process.
If that has changes recently everything is fine of course.