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Date:   Wed, 13 Mar 2019 12:51:25 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     "Paul E. McKenney" <paulmck@linux.ibm.com>
Cc:     Joel Fernandes <joel@joelfernandes.org>,
        linux-kernel@vger.kernel.org, rcu@vger.kernel.org,
        jiangshanlai@gmail.com, dipankar@in.ibm.com,
        mathieu.desnoyers@efficios.com, josh@joshtriplett.org,
        luto@kernel.org, byungchul.park@lge.com
Subject: Re: [PATCH tip/core/rcu 06/19] rcu: Add warning to detect
 half-interrupts
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On Wed, 13 Mar 2019 08:51:55 -0700
"Paul E. McKenney" <paulmck@linux.ibm.com> wrote:

> Does this mean that there is a better approach that Joel's suggestion?
> I believe he would end up with something like this:
> 
> 	WARN_ON_ONCE(IS_ENABLED(CONFIG_PROVE_RCU) && !in_irq());
> 
> It would be nice if there is something like this:
> 
> 	lockdep_assert_in_irq_handler();
> 
> But I haven't seen this.  (Not that I have looked particularly hard for
> such a thing, mind you!)

That would be trivial to implement:

#define lockdep_assert_in_irq() do {
		WARN_ON(debug_locks && !current->hardirq_context);
	} while (0)

-- Steve