linux-kernel - Re: [PATCHv6 01/16] x86/cpu: Enumerate the LASS feature bits

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Message-ID: <acce1e90-5742-4d44-8d7f-6aade7e490a1@intel.com>
Date: Fri, 20 Jun 2025 08:25:13 -0700
From: Dave Hansen <dave.hansen@...el.com>
To: "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
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 Yian Chen <yian.chen@...el.com>
Subject: Re: [PATCHv6 01/16] x86/cpu: Enumerate the LASS feature bits

On 6/20/25 06:53, Kirill A. Shutemov wrote:
> +static __always_inline void lass_clac(void)
> +{
> +	alternative("", "clac", X86_FEATURE_LASS);
> +}
> +
> +static __always_inline void lass_stac(void)
> +{
> +	alternative("", "stac", X86_FEATURE_LASS);
> +}

There are differing opinions on how to introduce code. Do you do it up
front and then use it later in the series? Or do you only introduce
infrastructure when you use it?

Doing what you have here (introduce first, use later) is fine. But it
does incur an increased burden of explaining things.

These two functions in particular mean that you have to at least allude
to how these get used later in the series.