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Date:   Sat, 26 Jun 2021 19:35:40 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc:     Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@kernel.org>,
        Robert Richter <rric@kernel.org>,
        Gabriel Krisman Bertazi <krisman@collabora.com>,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        linux-kernel@vger.kernel.org, Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        netdev <netdev@vger.kernel.org>, bpf@vger.kernel.org
Subject: Re: [PATCH] tracepoint: Do not warn on EEXIST or ENOENT
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On Sat, 26 Jun 2021 14:42:49 -0400 (EDT)
Mathieu Desnoyers <mathieu.desnoyers@efficios.com> wrote:

> > If BPF is OK with registering the same probe more than once if user
> > space expects it, we can add this patch, which allows the caller (in
> > this case BPF) to not warn if the probe being registered is already
> > registered, and keeps the idea that a probe registered twice is a bug
> > for all other use cases.  
> 
> How can removal of the duplicates be non buggy then ? The first removal will match both probes.

The registering of the first duplicate would fail with an error, but
will not warn. There would be no unregistering needed.

-- Steve