9732cafd9d
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>
52 lines
1.3 KiB
C
52 lines
1.3 KiB
C
/*
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* Copyright (C) 2013 Huawei Ltd.
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* Author: Jiang Liu <liuj97@gmail.com>
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*
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* Based on arch/arm/include/asm/jump_label.h
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#ifndef __ASM_JUMP_LABEL_H
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#define __ASM_JUMP_LABEL_H
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#include <linux/types.h>
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#include <asm/insn.h>
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#ifdef __KERNEL__
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#define JUMP_LABEL_NOP_SIZE AARCH64_INSN_SIZE
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static __always_inline bool arch_static_branch(struct static_key *key)
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{
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asm goto("1: nop\n\t"
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".pushsection __jump_table, \"aw\"\n\t"
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".align 3\n\t"
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".quad 1b, %l[l_yes], %c0\n\t"
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".popsection\n\t"
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: : "i"(key) : : l_yes);
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return false;
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l_yes:
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return true;
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}
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#endif /* __KERNEL__ */
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typedef u64 jump_label_t;
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struct jump_entry {
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jump_label_t code;
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jump_label_t target;
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jump_label_t key;
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};
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#endif /* __ASM_JUMP_LABEL_H */
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