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Date: Tue, 27 Jun 2017 16:48:22 -0700
From: Andi Kleen <ak@linux.intel.com>
To: "Liang, Kan" <kan.liang@intel.com>
Cc: Don Zickus <dzickus@redhat.com>, Thomas Gleixner <tglx@linutronix.de>,
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Subject: Re: [PATCH V2] kernel/watchdog: fix spurious hard lockups
Message-ID: <20170627234822.GL23705@tassilo.jf.intel.com>
References: <20170621144118.5939-1-kan.liang@intel.com>
 <alpine.DEB.2.20.1706212235550.2152@nanos>
 <20170622154450.2lua7fdmigcixldw@redhat.com>
 <alpine.DEB.2.20.1706230952190.2647@nanos>
 <20170623162907.l6inpxgztwwkeaoi@redhat.com>
 <alpine.DEB.2.20.1706232348020.2234@nanos>
 <20170626201927.3ak7fk3yvdzbb4ay@redhat.com>
 <20170627201249.ll34ecwhpme3vh2u@redhat.com>
 <37D7C6CF3E00A74B8858931C1DB2F0775371357D@SHSMSX103.ccr.corp.intel.com>
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> I haven't heard back any test result yet.
> 
> The above patch looks good to me.

This needs performance testing.  It may slow down performance or latency sensitive workloads.

> Which workaround do you prefer, the above one or the one checking timestamp?

I prefer the earlier patch, it has far less risk of performance issues.

-Andi