linux_dsm_epyc7002/arch/arm64/include/asm/jump_label.h
Jiang Liu 9732cafd9d arm64, jump label: optimize jump label implementation
Optimize jump label implementation for ARM64 by dynamically patching
kernel text.

Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jiang Liu <liuj97@gmail.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-01-08 15:23:53 +00:00

53 lines
1.3 KiB
C

/*
* 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
#include <linux/types.h>
#include <asm/insn.h>
#ifdef __KERNEL__
#define JUMP_LABEL_NOP_SIZE AARCH64_INSN_SIZE
static __always_inline bool arch_static_branch(struct static_key *key)
{
asm goto("1: nop\n\t"
".pushsection __jump_table, \"aw\"\n\t"
".align 3\n\t"
".quad 1b, %l[l_yes], %c0\n\t"
".popsection\n\t"
: : "i"(key) : : l_yes);
return false;
l_yes:
return true;
}
#endif /* __KERNEL__ */
typedef u64 jump_label_t;
struct jump_entry {
jump_label_t code;
jump_label_t target;
jump_label_t key;
};
#endif /* __ASM_JUMP_LABEL_H */