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From:   Nick Desaulniers <ndesaulniers@google.com>
Date:   Mon, 1 Jun 2020 13:48:45 -0700
Message-ID: <CAKwvOd=vf9J8PFcNod49Gh=2N-UGJrRo_OdgTfGa2Dh-H74=xw@mail.gmail.com>
Subject: Re: [PATCH v2 01/10] x86/percpu: Introduce size abstraction macros
To:     Brian Gerst <brgerst@gmail.com>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" <x86@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@kernel.org>, Borislav Petkov <bp@alien8.de>,
        "H . Peter Anvin" <hpa@zytor.com>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>
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On Sat, May 30, 2020 at 3:11 PM Brian Gerst <brgerst@gmail.com> wrote:
>
> In preparation for cleaning up the percpu operations, define macros for
> abstraction based on the width of the operation.
>
> Signed-off-by: Brian Gerst <brgerst@gmail.com>

Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>

> ---
>  arch/x86/include/asm/percpu.h | 30 ++++++++++++++++++++++++++++++
>  1 file changed, 30 insertions(+)
>
> diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h
> index 2278797c769d..19838e4f7a8f 100644
> --- a/arch/x86/include/asm/percpu.h
> +++ b/arch/x86/include/asm/percpu.h
> @@ -87,6 +87,36 @@
>   * don't give an lvalue though). */
>  extern void __bad_percpu_size(void);
>
> +#define __pcpu_type_1 u8
> +#define __pcpu_type_2 u16
> +#define __pcpu_type_4 u32
> +#define __pcpu_type_8 u64
> +
> +#define __pcpu_cast_1(val) ((u8)(((unsigned long) val) & 0xff))
> +#define __pcpu_cast_2(val) ((u16)(((unsigned long) val) & 0xffff))
> +#define __pcpu_cast_4(val) ((u32)(((unsigned long) val) & 0xffffffff))
> +#define __pcpu_cast_8(val) ((u64)(val))
> +
> +#define __pcpu_op1_1(op, dst) op "b " dst
> +#define __pcpu_op1_2(op, dst) op "w " dst
> +#define __pcpu_op1_4(op, dst) op "l " dst
> +#define __pcpu_op1_8(op, dst) op "q " dst
> +
> +#define __pcpu_op2_1(op, src, dst) op "b " src ", " dst
> +#define __pcpu_op2_2(op, src, dst) op "w " src ", " dst
> +#define __pcpu_op2_4(op, src, dst) op "l " src ", " dst
> +#define __pcpu_op2_8(op, src, dst) op "q " src ", " dst
> +
> +#define __pcpu_reg_1(mod, x) mod "q" (x)
> +#define __pcpu_reg_2(mod, x) mod "r" (x)
> +#define __pcpu_reg_4(mod, x) mod "r" (x)
> +#define __pcpu_reg_8(mod, x) mod "r" (x)
> +
> +#define __pcpu_reg_imm_1(x) "qi" (x)
> +#define __pcpu_reg_imm_2(x) "ri" (x)
> +#define __pcpu_reg_imm_4(x) "ri" (x)
> +#define __pcpu_reg_imm_8(x) "re" (x)
> +
>  #define percpu_to_op(qual, op, var, val)               \
>  do {                                                   \
>         typedef typeof(var) pto_T__;                    \
> --
> 2.25.4
>


-- 
Thanks,
~Nick Desaulniers