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Date:   Wed, 20 Mar 2019 18:59:52 +0100
From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     "Paul E. McKenney" <paulmck@linux.ibm.com>
Cc:     linux-kernel@vger.kernel.org,
        Josh Triplett <josh@joshtriplett.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        Joel Fernandes <joel@joelfernandes.org>, tglx@linutronix.de,
        Mike Galbraith <efault@gmx.de>
Subject: Re: [PATCH v2] rcu: Allow to eliminate softirq processing from
 rcutree
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On 2019-03-20 10:30:01 [-0700], Paul E. McKenney wrote:
> On Wed, Mar 20, 2019 at 05:35:32PM +0100, Sebastian Andrzej Siewior wrote:
> > On 2019-03-20 09:15:00 [-0700], Paul E. McKenney wrote:
> > > I am considering making it a module_param() to avoid namespace pollution,
> > > as it would become something like rcutree.nosoftirq.
> > > 
> > > Thoughts?
> > 
> > nope, perfect.
> 
> Please see below for an untested patch.  Thoughts?

> -	if (rcu_softirq_enabled) {
> +	if (!nosoftirq) {
>  		raise_softirq(RCU_SOFTIRQ);
>  	} else {

This double negation looks weird. Can we flip the logic somehow?
/me testing if it works…
> 							Thanx, Paul

Sebastian