Date: Tue, 24 Aug 2010 19:09:36 +0200
From: Robert Richter <robert.richter@amd.com>
To: Cyrill Gorcunov <gorcunov@gmail.com>
CC: Ingo Molnar <mingo@elte.hu>, Don Zickus <dzickus@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>, Lin Ming <ming.m.lin@intel.com>,
        "fweisbec@gmail.com" <fweisbec@gmail.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "Huang, Ying" <ying.huang@intel.com>, Yinghai Lu <yinghai@kernel.org>,
        Andi Kleen <andi@firstfloor.org>
Subject: Re: [PATCH -v3] perf, x86: try to handle unknown nmis with running
 perfctrs
Message-ID: <20100824170936.GH26154@erda.amd.com>
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 <20100820152510.GA4167@elte.hu>
 <20100823085339.GA26713@elte.hu>
 <20100824162252.GB5723@lenovo>
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On 24.08.10 12:22:52, Cyrill Gorcunov wrote:
> Btw, guys, I fail to see how new nmi_watchdog work, we have
> default_do_nmi
>   if (!(reason & 0xc0)) {
>     if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) == == NOTIFY_STOP)
>       return
>     if (nmi_watchdog_tick(regs, reason))
>       return
> 
> but perf_event_nmi_handler returns NOTIFY_STOP when watchdog is perf event
> and nmi_watchdog_tick _never_ called, or (most probably) I miss something?

The watchdog is disabled during profiling (perf and oprofile) by
calling disable_lapic_nmi_watchdog().

-Robert

-- 
Advanced Micro Devices, Inc.
Operating System Research Center

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