1 /* 2 * Copyright (C) 2013 Huawei Ltd. 3 * Author: Jiang Liu <liuj97@gmail.com> 4 * 5 * Based on arch/arm/include/asm/jump_label.h 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program. If not, see <http://www.gnu.org/licenses/>. 18 */ 19 #ifndef __ASM_JUMP_LABEL_H 20 #define __ASM_JUMP_LABEL_H 21 22 #ifndef __ASSEMBLY__ 23 24 #include <linux/types.h> 25 #include <asm/insn.h> 26 27 #define JUMP_LABEL_NOP_SIZE AARCH64_INSN_SIZE 28 29 static __always_inline bool arch_static_branch(struct static_key *key, 30 bool branch) 31 { 32 asm_volatile_goto( 33 "1: nop \n\t" 34 " .pushsection __jump_table, \"aw\" \n\t" 35 " .align 3 \n\t" 36 " .long 1b - ., %l[l_yes] - . \n\t" 37 " .quad %c0 - . \n\t" 38 " .popsection \n\t" 39 : : "i"(&((char *)key)[branch]) : : l_yes); 40 41 return false; 42 l_yes: 43 return true; 44 } 45 46 static __always_inline bool arch_static_branch_jump(struct static_key *key, 47 bool branch) 48 { 49 asm_volatile_goto( 50 "1: b %l[l_yes] \n\t" 51 " .pushsection __jump_table, \"aw\" \n\t" 52 " .align 3 \n\t" 53 " .long 1b - ., %l[l_yes] - . \n\t" 54 " .quad %c0 - . \n\t" 55 " .popsection \n\t" 56 : : "i"(&((char *)key)[branch]) : : l_yes); 57 58 return false; 59 l_yes: 60 return true; 61 } 62 63 #endif /* __ASSEMBLY__ */ 64 #endif /* __ASM_JUMP_LABEL_H */ 65