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Message-ID: <4D878445.6090709@gmail.com>
Date: Mon, 21 Mar 2011 20:00:53 +0300
From: Cyrill Gorcunov <gorcunov@gmail.com>
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To: Ingo Molnar <mingo@elte.hu>, Don Zickus <dzickus@redhat.com>,
        Jack Steiner <steiner@sgi.com>
CC: tglx@linutronix.de, hpa@zytor.com, x86@kernel.org,
        linux-kernel@vger.kernel.org, Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: [PATCH] x86, UV: Fix NMI handler for UV platforms
References: <20110321160135.GA31562@sgi.com> <20110321161425.GC23614@elte.hu> <4D877C4B.9090602@gmail.com> <4D878042.9080708@gmail.com>
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On 03/21/2011 07:43 PM, Cyrill Gorcunov wrote:
...
> 
> I think Jack might need to setup priority for his notifier, like
> 
> static struct notifier_block uv_dump_stack_nmi_nb = {
> 	.notifier_call	= uv_handle_nmi,
> 	.priority	= NMI_LOCAL_HIGH_PRIOR+1,
> };
> 
> so it would be called before perf nmi. Don, am I right?
> 
> Since for perf nmis we do have
> 
> static __read_mostly struct notifier_block perf_event_nmi_notifier = {
> 	.notifier_call		= perf_event_nmi_handler,
> 	.next			= NULL,
> 	.priority		= NMI_LOCAL_LOW_PRIOR,
> };
> 

  I must admit I've missed the fact that Jack has tried NMIs priorities, right?
x86_platform_ops seems to be a cleaner indeed (btw I think p4 pmu kgdb issue
is exactly the same problem) but same time this might end up in over-swelled
ideas behind this small code snippet. Dunno. Probably we need some per-cpu
system status for nmi reasons other than unknown nmis...

-- 
    Cyrill