1 /* Copyright (C) 2005-2020 Free Software Foundation, Inc. 2 Contributed by Richard Henderson <rth@redhat.com>. 3 4 This file is part of the GNU Offloading and Multi Processing Library 5 (libgomp). 6 7 Libgomp is free software; you can redistribute it and/or modify it 8 under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3, or (at your option) 10 any later version. 11 12 Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY 13 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 14 FOR A PARTICULAR PURPOSE. See the GNU General Public License for 15 more details. 16 17 Under Section 7 of GPL version 3, you are granted additional 18 permissions described in the GCC Runtime Library Exception, version 19 3.1, as published by the Free Software Foundation. 20 21 You should have received a copy of the GNU General Public License and 22 a copy of the GCC Runtime Library Exception along with this program; 23 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 24 <http://www.gnu.org/licenses/>. */ 25 26 /* Provide target-specific access to the futex system call. */ 27 28 #ifndef SYS_futex 29 #define SYS_futex 394 30 #endif 31 32 33 static inline void 34 futex_wait (int *addr, int val) 35 { 36 register long sc_0 __asm__("$0"); 37 register long sc_16 __asm__("$16"); 38 register long sc_17 __asm__("$17"); 39 register long sc_18 __asm__("$18"); 40 register long sc_19 __asm__("$19"); 41 42 sc_0 = SYS_futex; 43 sc_16 = (long) addr; 44 sc_17 = gomp_futex_wait; 45 sc_18 = val; 46 sc_19 = 0; 47 __asm volatile ("callsys" 48 : "=r" (sc_0), "=r"(sc_19) 49 : "0"(sc_0), "r" (sc_16), "r"(sc_17), "r"(sc_18), "1"(sc_19) 50 : "$1", "$2", "$3", "$4", "$5", "$6", "$7", "$8", 51 "$22", "$23", "$24", "$25", "$27", "$28", "memory"); 52 if (__builtin_expect (sc_19, 0) && sc_0 == ENOSYS) 53 { 54 gomp_futex_wait &= ~FUTEX_PRIVATE_FLAG; 55 gomp_futex_wake &= ~FUTEX_PRIVATE_FLAG; 56 sc_0 = SYS_futex; 57 sc_17 &= ~FUTEX_PRIVATE_FLAG; 58 sc_19 = 0; 59 __asm volatile ("callsys" 60 : "=r" (sc_0), "=r"(sc_19) 61 : "0"(sc_0), "r" (sc_16), "r"(sc_17), "r"(sc_18), 62 "1"(sc_19) 63 : "$1", "$2", "$3", "$4", "$5", "$6", "$7", "$8", 64 "$22", "$23", "$24", "$25", "$27", "$28", "memory"); 65 } 66 } 67 68 static inline void 69 futex_wake (int *addr, int count) 70 { 71 register long sc_0 __asm__("$0"); 72 register long sc_16 __asm__("$16"); 73 register long sc_17 __asm__("$17"); 74 register long sc_18 __asm__("$18"); 75 register long sc_19 __asm__("$19"); 76 77 sc_0 = SYS_futex; 78 sc_16 = (long) addr; 79 sc_17 = gomp_futex_wake; 80 sc_18 = count; 81 __asm volatile ("callsys" 82 : "=r" (sc_0), "=r"(sc_19) 83 : "0"(sc_0), "r" (sc_16), "r"(sc_17), "r"(sc_18) 84 : "$1", "$2", "$3", "$4", "$5", "$6", "$7", "$8", 85 "$22", "$23", "$24", "$25", "$27", "$28", "memory"); 86 if (__builtin_expect (sc_19, 0) && sc_0 == ENOSYS) 87 { 88 gomp_futex_wait &= ~FUTEX_PRIVATE_FLAG; 89 gomp_futex_wake &= ~FUTEX_PRIVATE_FLAG; 90 sc_0 = SYS_futex; 91 sc_17 &= ~FUTEX_PRIVATE_FLAG; 92 __asm volatile ("callsys" 93 : "=r" (sc_0), "=r"(sc_19) 94 : "0"(sc_0), "r" (sc_16), "r"(sc_17), "r"(sc_18) 95 : "$1", "$2", "$3", "$4", "$5", "$6", "$7", "$8", 96 "$22", "$23", "$24", "$25", "$27", "$28", "memory"); 97 } 98 } 99 100 static inline void 101 cpu_relax (void) 102 { 103 __asm volatile ("" : : : "memory"); 104 } 105