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Date:   Fri, 21 Oct 2022 08:32:54 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     richard clark <richard.xnu.clark@gmail.com>
Cc:     bristot@kernel.org, linux-trace-devel@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: Question about 'for_each_kernel_tracepoint(...)' function
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On Fri, 21 Oct 2022 11:51:20 +0800
richard clark <richard.xnu.clark@gmail.com> wrote:

> On Fri, Oct 21, 2022 at 10:12 AM Steven Rostedt <rostedt@goodmis.org> wrote:
> >
> > On Fri, 21 Oct 2022 09:43:14 +0800
> > richard clark <richard.xnu.clark@gmail.com> wrote:
> >
> >  
> > > Ah, as you can see that I did it, but the result is not what I
> > > expected :-). Help?  
> >
> > Looking at the code, I see it does indeed only look at builtin tracepoints.  
> 
> What the logic behind is not to implement a function like
> 'for_each_tracepoints' instead of 'for_each_kernel_tracepoint' to find
> all the TPs defined by both builtin kernel and external kernel
> modules, just like we can find all the kernel symbols and exported
> symbols from external module?

Why? It's not needed upstream. If you push your code upstream and it's
something to get accepted, then we can think about adding that.

> 
> >
> > But if you want one module to have access to the tracepoints of another,
> > then you can have the first one export it.
> >
> > EXPORT_SYMBOL_TRACEPOINT_GPL(function_event_a);
> >
> > And then module b should have access to it.
> >  
> Yes, but module b needs to register a new probe call back function for
> the new TPs defined by module a in my case, so first it needs to find
> the TPs defined by module a. Any comments?

No, because I have no idea what you are doing or why you need this.

-- Steve