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Date:   Tue, 26 Mar 2019 22:20:41 +0100 (CET)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
cc:     "Paul E. McKenney" <paulmck@linux.ibm.com>,
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        "Ravi V. Shankar" <ravi.v.shankar@intel.com>, x86@kernel.org,
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        Ricardo Neri <ricardo.neri@intel.com>,
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Subject: Re: [RFC PATCH v2 09/14] watchdog/hardlockup: Make arch_touch_nmi_watchdog()
 to hpet-based implementation
In-Reply-To: <20190301011713.GA8058@ranerica-svr.sc.intel.com>
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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.

Thanks,

	tglx