Re: [PATCH tip/core/rcu 06/19] rcu: Add warning to detect half-interrupts

[Steven Rostedt]

On Wed, 13 Mar 2019 08:51:55 -0700
"Paul E. McKenney" <paulmck@xxxxxxxxxxxxx> 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