linux_dsm_epyc7002/arch/riscv/include/asm/jump_label.h
Emil Renner Berthing ebc00dde8a
riscv: Add jump-label implementation
Add jump-label implementation based on the ARM64 version
and add CONFIG_JUMP_LABEL=y to the defconfigs.

Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Reviewed-by: Björn Töpel <bjorn.topel@gmail.com>
Tested-by: Björn Töpel <bjorn.topel@gmail.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30 11:37:43 -07:00

61 lines
1.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2020 Emil Renner Berthing
*
* Based on arch/arm64/include/asm/jump_label.h
*/
#ifndef __ASM_JUMP_LABEL_H
#define __ASM_JUMP_LABEL_H
#ifndef __ASSEMBLY__
#include <linux/types.h>
#include <asm/asm.h>
#define JUMP_LABEL_NOP_SIZE 4
static __always_inline bool arch_static_branch(struct static_key *key,
bool branch)
{
asm_volatile_goto(
" .option push \n\t"
" .option norelax \n\t"
" .option norvc \n\t"
"1: nop \n\t"
" .option pop \n\t"
" .pushsection __jump_table, \"aw\" \n\t"
" .align " RISCV_LGPTR " \n\t"
" .long 1b - ., %l[label] - . \n\t"
" " RISCV_PTR " %0 - . \n\t"
" .popsection \n\t"
: : "i"(&((char *)key)[branch]) : : label);
return false;
label:
return true;
}
static __always_inline bool arch_static_branch_jump(struct static_key *key,
bool branch)
{
asm_volatile_goto(
" .option push \n\t"
" .option norelax \n\t"
" .option norvc \n\t"
"1: jal zero, %l[label] \n\t"
" .option pop \n\t"
" .pushsection __jump_table, \"aw\" \n\t"
" .align " RISCV_LGPTR " \n\t"
" .long 1b - ., %l[label] - . \n\t"
" " RISCV_PTR " %0 - . \n\t"
" .popsection \n\t"
: : "i"(&((char *)key)[branch]) : : label);
return false;
label:
return true;
}
#endif /* __ASSEMBLY__ */
#endif /* __ASM_JUMP_LABEL_H */