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Date:   Tue, 21 May 2019 14:43:26 -0700
From:   Alexei Starovoitov <alexei.starovoitov@gmail.com>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Kris Van Hees <kris.van.hees@oracle.com>, netdev@vger.kernel.org,
        bpf@vger.kernel.org, dtrace-devel@oss.oracle.com,
        linux-kernel@vger.kernel.org, mhiramat@kernel.org, acme@kernel.org,
        ast@kernel.org, daniel@iogearbox.net, peterz@infradead.org
Subject: Re: [RFC PATCH 00/11] bpf, trace, dtrace: DTrace BPF program type
 implementation and sample use
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On Tue, May 21, 2019 at 05:36:18PM -0400, Steven Rostedt wrote:
> On Tue, 21 May 2019 13:55:34 -0700
> Alexei Starovoitov <alexei.starovoitov@gmail.com> wrote:
> 
> > > The reasons for these patches is because I cannot do the same with the existing
> > > implementation.  Yes, I can do some of it or use some workarounds to accomplish
> > > kind of the same thing, but at the expense of not being able to do what I need
> > > to do but rather do some kind of best effort alternative.  That is not the goal
> > > here.  
> > 
> > what you call 'workaround' other people call 'feature'.
> > The kernel community doesn't accept extra code into the kernel
> > when user space can do the same.
> 
> If that was really true, all file systems would be implemented on
> FUSE ;-)
> 
> I was just at a technical conference that was not Linux focused, and I
> talked to a lot of admins that said they would love to have Dtrace
> scripts working on Linux unmodified.
> 
> I need to start getting more familiar with the workings of eBPF and
> then look at what Dtrace has to see where something like this can be
> achieved, but right now just NACKing patches outright isn't being
> helpful. If you are not happy with this direction, I would love to see
> conversations where Kris shows you exactly what is required (from a
> feature perspective, not an implementation one) and we come up with a
> solution.

Steve,
sounds like you've missed all prior threads.
The feedback was given to Kris it was very clear:
implement dtrace the same way as bpftrace is working with bpf.
No changes are necessary to dtrace scripts
and no kernel changes are necessary.