linux-kernel - Re: [PATCH 1/8] x86/mce: Stop mce_reign() from re-computing severity for every CPU

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Date:   Mon, 14 Sep 2020 19:21:07 +0200
From:   Borislav Petkov <bp@...en8.de>
To:     Tony Luck <tony.luck@...el.com>
Cc:     Youquan Song <youquan.song@...el.com>, x86@...nel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/8] x86/mce: Stop mce_reign() from re-computing severity
 for every CPU

On Tue, Sep 08, 2020 at 10:55:12AM -0700, Tony Luck wrote:
> Back in:
> 
> commit 20d51a426fe9 ("x86/mce: Reuse one of the u16 padding fields in 'struct mce'")
> 
> a field was added to "struct mce" to save the computed error severity.
> 
> Make use of this in mce_reign() to avoid re-computing the severity
> for every CPU.

Yah, could go as a standalone optimization...

> In the case where we panic, we do still need one call to mce_severity to
> provide the correct message giving the reason for the panic.

... but pls do not use the "we" formulation as this ambiguous. I'll fix
that up now.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette