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Date: Fri, 5 Aug 2016 12:17:06 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org,
        Ingo Molnar <mingo@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Clark Williams <williams@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>, Jon Masters <jcm@redhat.com>,
        Daniel Wagner <wagi@monom.org>, Carsten Emde <C.Emde@osadl.org>
Subject: Re: [RFC][PATCH 4/3] tracing: Add NMI tracing in hwlat detector
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On Fri, 5 Aug 2016 17:40:43 +0200
Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote:


> > Ah, this is when we have GENERIC_SCHED_CLOCK, which would break tracing
> > if any arch that has this also has NMIs. Probably need to look at arm64.  
> 
> arm64 should use the generic code as they don't provide sched_clock()
> (and I doubt they go for the weak jiffy version).

And I'm guessing that arm64 supports NMIs. Is there no NMI safe clock?
I probably need to look at the tracing code. Because you can have the
same issue while tracing in an NMI as well.

-- Steve