Re: [PATCH v7 6/7] arm64, jump label: optimize jump label implementation

[Will Deacon <will.deacon@arm.com>]

On Sun, Dec 22, 2013 at 03:25:42PM +0000, Jiang Liu wrote:
> Optimize jump label implementation for ARM64 by dynamically patching
> kernel text.

Almost!

> diff --git a/arch/arm64/include/asm/jump_label.h b/arch/arm64/include/asm/jump_label.h
> new file mode 100644
> index 0000000..47cd130
> --- /dev/null
> +++ b/arch/arm64/include/asm/jump_label.h
> @@ -0,0 +1,51 @@
> +/*
> + * Copyright (C) 2013 Huawei Ltd.
> + * Author: Jiang Liu <liuj97@gmail.com>
> + *
> + * Based on arch/arm/include/asm/jump_label.h
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program.  If not, see <http://www.gnu.org/licenses/>.
> + */
> +#ifndef _ASM_JUMP_LABEL_H
> +#define _ASM_JUMP_LABEL_H

It's actually prefixed with double-underscore in our other headers.

> +#include <linux/types.h>
> +
> +#ifdef __KERNEL__
> +
> +#define JUMP_LABEL_NOP_SIZE		4

I know you didn't like including asm/insn.h, but I don't see why that's such
a problem. Does it cause a circular dependency or something?

Will