From mboxrd@z Thu Jan  1 00:00:00 1970
From: Borislav Petkov <bp@alien8.de>
Subject: Re: [RESEND PATCH 1/3] x86: Adding structs to reflect cpuid fields
Date: Wed, 17 Sep 2014 17:22:21 +0200
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Cc: Nadav Amit <namit@cs.technion.ac.il>,
	Ingo Molnar <mingo@kernel.org>,
	Paolo Bonzini <pbonzini@redhat.com>,
	"H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	the arch/x86 maintainers <x86@kernel.org>,
	kvm <kvm@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Radim =?utf-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>
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On Wed, Sep 17, 2014 at 05:04:33PM +0200, Radim Kr=C4=8Dm=C3=A1=C5=99 w=
rote:
> which would result in a similar if-else hack
>=20
>   if (family > X)
>   	ebx.split.max_monitor_line_size_after_family_X =3D 0
>   else
>   	ebx.split.max_monitor_line_size =3D 0
>=20
> 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 =3D cpuid_ebx(5);

	if (family > X)
		max_monitor_line_size =3D cpuid & MASK_FAM_X;
	else
		max_monitor_line_size =3D 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.

--=20
Regards/Gruss,
    Boris.
--