Date: Mon, 16 Nov 2015 21:04:03 -0800
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Arjan van de Ven <arjan@linux.intel.com>
Cc: Josh Triplett <josh@joshtriplett.org>,
        Jacob Pan <jacob.jun.pan@linux.intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@redhat.com>,
        John Stultz <john.stultz@linaro.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
        Len Brown <len.brown@intel.com>,
        Rafael Wysocki <rafael.j.wysocki@intel.com>,
        Eduardo Valentin <edubezval@gmail.com>, Paul Turner <pjt@google.com>
Subject: Re: [PATCH 2/4] timer: relax tick stop in idle entry
Message-ID: <20151117050403.GQ5184@linux.vnet.ibm.com>
Reply-To: paulmck@linux.vnet.ibm.com
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On Mon, Nov 16, 2015 at 06:57:14PM -0800, Arjan van de Ven wrote:
> On 11/16/2015 6:53 PM, Paul E. McKenney wrote:
> >Fair point.  When in the five-jiffy throttling state, what can wake up
> >a CPU?  In an earlier version of this proposal, the answer was "nothing",
> >but maybe that has changed.
> 
> device interrupts are likely to wake the cpus.

OK, that I cannot help you with.  But presumably if the interrupt handler
does a wakeup (or similar), that is deferred to the end of the throttling
interval?  Timers are also deferred, including hrtimers?

							Thanx, Paul

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