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Date:   Mon, 8 Apr 2019 19:05:30 -0700
From:   Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     "Paul E. McKenney" <paulmck@linux.ibm.com>,
        Ingo Molnar <mingo@kernel.org>, Borislav Petkov <bp@suse.de>,
        Ashok Raj <ashok.raj@intel.com>,
        Andi Kleen <andi.kleen@intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        "Ravi V. Shankar" <ravi.v.shankar@intel.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org,
        Ricardo Neri <ricardo.neri@intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>, Tony Luck <tony.luck@intel.com>,
        "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
        Don Zickus <dzickus@redhat.com>,
        Nicholas Piggin <npiggin@gmail.com>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Frederic Weisbecker <frederic@kernel.org>,
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Subject: Re: [RFC PATCH v2 09/14] watchdog/hardlockup: Make
 arch_touch_nmi_watchdog() to hpet-based implementation
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On Tue, Mar 26, 2019 at 10:20:41PM +0100, Thomas Gleixner wrote:
> On Thu, 28 Feb 2019, Ricardo Neri wrote:
> > > > 
> > > > -#if defined(CONFIG_HARDLOCKUP_DETECTOR_PERF)
> > > > +#if defined(CONFIG_HARDLOCKUP_DETECTOR_PERF) || \
> > > > +    defined(CONFIG_X86_HARDLOCKUP_DETECTOR_HPET)
> > > 
> > > Why not instead make CONFIG_X86_HARDLOCKUP_DETECTOR_HPET select
> > > CONFIG_HARDLOCKUP_DETECTOR_PERF?  Keep the arch-specific details
> > > in the arch-specific files and all that.
> > 
> > Thanks for your feedback, Paul! The HPET implementation does not use
> > perf. Thus, in my opinion is not correct for the HPET HLD to select
> > the perf implementation. Patch 8 of this series splits the perf-specific
> > code and the generic hardlockup detector code. Does this make sense?
> 
> That's what intermediate config symbols are for.
> 
> config HARDLOCKUP_DETECTOR_CORE
>        bool
> 
> And make both PERF and HPET select it.

I'll implement it in this manner.

Thanks and BR,
Ricardo