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/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2023 Loongson Technology Corporation Limited
*
* 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>
#define JUMP_LABEL_NOP_SIZE 4
/* This macro is also expanded on the Rust side. */
#define JUMP_TABLE_ENTRY(key, label) \
".pushsection __jump_table, \"aw\" \n\t" \
".align 3 \n\t" \
".long 1b - ., " label " - . \n\t" \
".quad " key " - . \n\t" \
".popsection \n\t"
#define ARCH_STATIC_BRANCH_ASM(key, label) \
"1: nop \n\t" \
JUMP_TABLE_ENTRY(key, label)
static __always_inline bool arch_static_branch(struct static_key * const key, const bool branch)
{
asm goto(
ARCH_STATIC_BRANCH_ASM("%0", "%l[l_yes]")
: : "i"(&((char *)key)[branch]) : : l_yes);
return false;
l_yes:
return true;
}
static __always_inline bool arch_static_branch_jump(struct static_key * const key, const bool branch)
{
asm goto(
"1: b %l[l_yes] \n\t"
JUMP_TABLE_ENTRY("%0", "%l[l_yes]")
: : "i"(&((char *)key)[branch]) : : l_yes);
return false;
l_yes:
return true;
}
#endif /* __ASSEMBLY__ */
#endif /* __ASM_JUMP_LABEL_H */
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