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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>
59 lines
1.6 KiB
C
59 lines
1.6 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/kernel/jump_label.c
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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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#include <linux/kernel.h>
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#include <linux/jump_label.h>
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#include <asm/insn.h>
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#ifdef HAVE_JUMP_LABEL
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static void __arch_jump_label_transform(struct jump_entry *entry,
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enum jump_label_type type,
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bool is_static)
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{
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void *addr = (void *)entry->code;
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u32 insn;
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if (type == JUMP_LABEL_ENABLE) {
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insn = aarch64_insn_gen_branch_imm(entry->code,
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entry->target,
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AARCH64_INSN_BRANCH_NOLINK);
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} else {
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insn = aarch64_insn_gen_nop();
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}
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if (is_static)
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aarch64_insn_patch_text_nosync(addr, insn);
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else
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aarch64_insn_patch_text(&addr, &insn, 1);
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}
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void arch_jump_label_transform(struct jump_entry *entry,
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enum jump_label_type type)
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{
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__arch_jump_label_transform(entry, type, false);
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}
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void arch_jump_label_transform_static(struct jump_entry *entry,
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enum jump_label_type type)
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{
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__arch_jump_label_transform(entry, type, true);
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}
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#endif /* HAVE_JUMP_LABEL */
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