Message-ID: <1339685789.2559.37.camel@twins>
Subject: Re: [RFC patch 2/5] smpboot: Provide infrastructure for percpu
 hotplug threads
From: Peter Zijlstra <peterz@infradead.org>
To: paulmck@linux.vnet.ibm.com
Cc: Thomas Gleixner <tglx@linutronix.de>, LKML <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
        "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>,
        Rusty Russell <rusty@rustcorp.com.au>, Tejun Heo <tj@kernel.org>
Date: Thu, 14 Jun 2012 16:56:29 +0200
In-Reply-To: <20120614144734.GA2458@linux.vnet.ibm.com>
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On Thu, 2012-06-14 at 07:47 -0700, Paul E. McKenney wrote:
> RCU callback processing consumes the entire CPU in RCU_BOOST case where
> processing runs at real-time priority.  This is analogous to RT throttling
> in the scheduler. 

But previously we can in non-preemptible softirq context, why would if
behave differently when done from a RT task?

Also, no its not quite like the throttling, that really idles the cpu
even if there's no SCHED_OTHER tasks to run.
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