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Date:   Mon, 9 Mar 2020 15:09:40 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Alexei Starovoitov <ast@kernel.org>,
        paulmck <paulmck@kernel.org>,
        "Joel Fernandes, Google" <joel@joelfernandes.org>,
        Frederic Weisbecker <frederic@kernel.org>
Subject: Re: Instrumentation and RCU
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On Mon, 9 Mar 2020 14:52:40 -0400 (EDT)
Mathieu Desnoyers <mathieu.desnoyers@efficios.com> wrote:

> And when I say "go back to plain RCU", I really mean removing use of SRCU
> from the tracepoints until we have other purposes for it (e.g. taking
> faults within specific tracepoint probes such as syscall enter/exit).

Actually, with both you and Alexei talking about having a sleeping
tracepoint callback, where we can add a can sleep check (but not in the
DO_TRACE macro, I would think that registered sleeping callbacks would be
its own callback), I would think we do not want to remove the SRCU usage.

-- Steve