linux-kernel - Re: [PATCH 2/5] [RESEND] x86: avoid unneeded __div64

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Message-ID: <20230802172030.GEZMqQXmeb98Tm+Qhg@fat_crate.local>
Date:   Wed, 2 Aug 2023 19:20:30 +0200
From:   Borislav Petkov <bp@...en8.de>
To:     Arnd Bergmann <arnd@...db.de>
Cc:     Arnd Bergmann <arnd@...nel.org>, linux-kernel@...r.kernel.org,
        x86@...nel.org, Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
        "H. Peter Anvin" <hpa@...or.com>
Subject: Re: [PATCH 2/5] [RESEND] x86: avoid unneeded __div64_32 function
 definition

On Tue, Aug 01, 2023 at 10:48:02PM +0200, Arnd Bergmann wrote:
> Right, makes sense. How about this version?
> 
> --- a/arch/x86/include/asm/div64.h
> +++ b/arch/x86/include/asm/div64.h
> @@ -71,6 +71,11 @@ static inline u64 mul_u32_u32(u32 a, u32 b)
>  }
>  #define mul_u32_u32 mul_u32_u32
>  
> +/*
> + * __div64_32() is never called on x86, so prevent the
> + * generic definition from getting built.
> + */
> +#define __div64_32
>  
>  #else
>  # include <asm-generic/div64.h>

Yap.

Thx.

-- 
Regards/Gruss,
    Boris.

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