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Date: Wed, 27 Jul 2016 14:53:47 -0500 (CDT)
From: Christoph Lameter <cl@linux.com>
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To: Chris Metcalf <cmetcalf@mellanox.com>
cc: Gilad Ben Yossef <giladb@mellanox.com>,
        Steven Rostedt <rostedt@goodmis.org>, Ingo Molnar <mingo@kernel.org>,
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        Thomas Gleixner <tglx@linutronix.de>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
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        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Andy Lutomirski <luto@amacapital.net>,
        Daniel Lezcano <daniel.lezcano@linaro.org>, linux-doc@vger.kernel.org,
        linux-api@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: clocksource_watchdog causing scheduling of timers every second
 (was [v13] support "task_isolation" mode)
In-Reply-To: <eacd22ec-fc87-290e-ee5f-21b8e879b059@mellanox.com>
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On Wed, 27 Jul 2016, Chris Metcalf wrote:

> Looks good.  Did you omit the equivalent fix in clocksource_start_watchdog()
> on purpose?  For now I just took your change, but tweaked it to add the
> equivalent diff with cpumask_first_and() there.

Can the watchdog be started on an isolated cpu at all? I would expect that
the code would start a watchdog only on a housekeeping cpu.