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Date: Wed, 23 Apr 2025 17:27:21 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>, Linux Trace Kernel
 <linux-trace-kernel@vger.kernel.org>, Mathieu Desnoyers
 <mathieu.desnoyers@efficios.com>, Masami Hiramatsu <mhiramat@kernel.org>,
 Peter Zijlstra <peterz@infradead.org>, David Ahern <dsahern@kernel.org>,
 Juri Lelli <juri.lelli@gmail.com>, Breno Leitao <leitao@debian.org>,
 netdev@vger.kernel.org, Alexei Starovoitov <alexei.starovoitov@gmail.com>,
 bpf@vger.kernel.org, Gabriele Monaco <gmonaco@redhat.com>
Subject: Re: [RFC][PATCH] tracepoint: Have tracepoints created with
 DECLARE_TRACE() have _tp suffix
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On Wed, 23 Apr 2025 14:21:24 -0700
Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote:

> BPF by itself doesn't have any API to list tracepoints, so in that
> sense, no, BPF doesn't expose *the list* of those tracepoints. But the
> same can be said about kprobes or normal tracepoints. But it is
> allowed to attempt to attach to those tracepoints by just specifying
> their name as a string.
> 
> I guess I'm confused about what "accessing only from code within the
> kernel" means. In my mind BPF isn't really "code within the kernel",
> but we are getting into the philosophical area now :) I just wanted to
> point out that this is consumable/attachable with BPF just like any
> other tracepoint, so it's not just kernel/module code that can attach
> to them.

To continue the philosophical debate ;-) I'll argue that a BPF program runs
inside the kernel just like a module would. Hence, a BPF program is in
kernel space. In fact, from what I understand, that's the entire point of
BPF. To run in kernel space!

-- Steve