Date: Tue, 12 May 2015 11:32:02 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>,
        Gilad Ben Yossef <giladb@ezchip.com>,
        Steven Rostedt <rostedt@goodmis.org>, Ingo Molnar <mingo@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Rik van Riel <riel@redhat.com>, Tejun Heo <tj@kernel.org>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Christoph Lameter <cl@linux.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 3/6] dataplane nohz: run softirqs synchronously on user
 entry
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On Mon, May 11, 2015 at 04:13:16PM -0400, Chris Metcalf wrote:
> The thing you want to avoid is having two processes both
> runnable at once

Right, because as soon as nr_running > 1 we kill the entire nohz_full
thing. RT or not for ksoftirqd doesn't matter.

Then again, like interrupts, you basically want to avoid softirqs in
this mode.

So I think the right solution is to figure out why the softirqs get
raised and cure that.
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