linux-kernel - Re: [PATCH] x86/mce: Distirbute the clear operation of mces_seen to Per-CPU rather than only monarch CPU

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Message-ID: <20140519072619.GA6311@pd.tnic>
Date:	Mon, 19 May 2014 09:26:19 +0200
From:	Borislav Petkov <bp@...en8.de>
To:	Chen Yucong <slaoub@...il.com>
Cc:	tony.luck@...el.com, linux-kernel@...r.kernel.org,
	linux-edac@...r.kernel.org
Subject: Re: [PATCH] x86/mce: Distirbute the clear operation of mces_seen to
 Per-CPU rather than only monarch CPU

On Mon, May 19, 2014 at 09:55:40AM +0800, Chen Yucong wrote:
> But all other CPUs also have to wait monarch CPU to exit from mce_end.
> What's the difference between monarch CPU and Per-CPU for clearing
> mces_seen? In practice, there is no difference between them. If we use
> monarch CPU to clear mces_seen, then Per-CPU variable can not play out
> its advantage.

I'll let you stare at mce_reign() a little bit longer... Also, pay
attention to its callsite, that might help.

> Well, in that case, why is there a need for time-out machine in MCE
> handler?

I'll let you figure this out yourself too - it is only fair.

:-)

-- 
Regards/Gruss,
    Boris.

Sent from a fat crate under my desk. Formatting is fine.
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