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Date: Thu, 13 Jun 2024 16:56:36 +0200
From: Borislav Petkov <bp@alien8.de>
To: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
	Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
	"Rafael J. Wysocki" <rafael@kernel.org>,
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	Adrian Hunter <adrian.hunter@intel.com>,
	Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>,
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	"Kalra, Ashish" <ashish.kalra@amd.com>,
	Sean Christopherson <seanjc@google.com>,
	"Huang, Kai" <kai.huang@intel.com>,
	Ard Biesheuvel <ardb@kernel.org>, Baoquan He <bhe@redhat.com>,
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Subject: Re: [PATCHv11 18/19] x86/acpi: Add support for CPU offlining for
 ACPI MADT wakeup method
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On Thu, Jun 13, 2024 at 04:41:00PM +0300, Kirill A. Shutemov wrote:
> It is easy enough to do. See the patch below.

Thanks, will have a look.

> But I am not sure if I can justify it properly. If someone doesn't really
> need 5-level paging, disabling it at compile-time would save ~34K of
> kernel code with the configuration.
> 
> Is it worth saving ~100 lines of code?

Well, it goes both ways: is it worth saving ~34K kernel text and for that make
the code a lot less conditional, more readable, contain less ugly ifdeffery,
...?

-- 
Regards/Gruss,
    Boris.

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