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Date: Wed, 17 Sep 2014 17:22:21 +0200
From: Borislav Petkov <bp@alien8.de>
To: Radim =?utf-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>
Cc: Nadav Amit <namit@cs.technion.ac.il>, Ingo Molnar <mingo@kernel.org>,
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Subject: Re: [RESEND PATCH 1/3] x86: Adding structs to reflect cpuid fields
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On Wed, Sep 17, 2014 at 05:04:33PM +0200, Radim Krčmář wrote:
> which would result in a similar if-else hack
> 
>   if (family > X)
>   	ebx.split.max_monitor_line_size_after_family_X = 0
>   else
>   	ebx.split.max_monitor_line_size = 0
> 
> other options are
>   ebx.split.after_family_X.max_monitor_line_size
> or even
>   ebx.split.max_monitor_line_size.after_family_X

And how is that better than simply doing

	cpuid = cpuid_ebx(5);

	if (family > X)
		max_monitor_line_size = cpuid & MASK_FAM_X;
	else
		max_monitor_line_size = cpuid & MASK_BEFORE_FAM_X;

?

With proper variable naming all is perfectly clear, readable
and simple. You don't need to open even the CPUID manual - the
variable tells you you're getting the max monitor line size -
"ebx.split.max_monitor_line_size_after_family_X" needs me to parse it
with my eyes first.

-- 
Regards/Gruss,
    Boris.
--