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Date:   Tue, 26 Oct 2021 11:44:35 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Huan Xie <xiehuan09@gmail.com>
Cc:     Masami Hiramatsu <mhiramat@kernel.org>, mingo@redhat.com,
        chenhuacai@kernel.org, linux-kernel@vger.kernel.org,
        Tom Zanussi <zanussi@kernel.org>
Subject: Re: [RFC PATCH v2] trace: Add trace any kernel object
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On Tue, 26 Oct 2021 23:40:03 +0800
Huan Xie <xiehuan09@gmail.com> wrote:

> > > static void trace_object_trigger(struct event_trigger_data *data,
> > > struct trace_buffer *buffer,  void *rec,
> > >                    struct ring_buffer_event *event)  
> >
> >
> > OK, so let me ask this question. What is it that you want to see?  
> 
> Thanks, I got your point now,  my original idea was to just track the
> flow of objects.

Well, the current patch set doesn't really show any flow of objects, as it
only records a value that never changes until the next kprobe is hit, and
we get that from the kprobe itself.


> >
> > And let's say I want to monitor that __bi_cnt while functions are being
> > traced. What would be *really cool*, is to mark that value!  
> 
> This is really cool to  get the change of the value. And is a good
> feature enhancement.
> 

Right, and this is what I thought the purpose of your patch was! :-)

And why I got really excited about it. So I don't see this as a feature
enhancement to your patch, but the feature enhancement that your patch can
give us.

-- Steve