mutex.h revision 1.1.18.2
1 1.1.18.2 jdolecek /* $NetBSD: mutex.h,v 1.1.18.2 2017/12/03 11:36:39 jdolecek Exp $ */ 2 1.1.18.2 jdolecek 3 1.1.18.2 jdolecek /*- 4 1.1.18.2 jdolecek * Copyright (c) 2002, 2007 The NetBSD Foundation, Inc. 5 1.1.18.2 jdolecek * All rights reserved. 6 1.1.18.2 jdolecek * 7 1.1.18.2 jdolecek * This code is derived from software contributed to The NetBSD Foundation 8 1.1.18.2 jdolecek * by Jason R. Thorpe and Andrew Doran. 9 1.1.18.2 jdolecek * 10 1.1.18.2 jdolecek * Redistribution and use in source and binary forms, with or without 11 1.1.18.2 jdolecek * modification, are permitted provided that the following conditions 12 1.1.18.2 jdolecek * are met: 13 1.1.18.2 jdolecek * 1. Redistributions of source code must retain the above copyright 14 1.1.18.2 jdolecek * notice, this list of conditions and the following disclaimer. 15 1.1.18.2 jdolecek * 2. Redistributions in binary form must reproduce the above copyright 16 1.1.18.2 jdolecek * notice, this list of conditions and the following disclaimer in the 17 1.1.18.2 jdolecek * documentation and/or other materials provided with the distribution. 18 1.1.18.2 jdolecek * 19 1.1.18.2 jdolecek * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 1.1.18.2 jdolecek * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 1.1.18.2 jdolecek * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 1.1.18.2 jdolecek * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 1.1.18.2 jdolecek * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 1.1.18.2 jdolecek * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 1.1.18.2 jdolecek * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 1.1.18.2 jdolecek * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 1.1.18.2 jdolecek * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 1.1.18.2 jdolecek * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 1.1.18.2 jdolecek * POSSIBILITY OF SUCH DAMAGE. 30 1.1.18.2 jdolecek */ 31 1.1.18.2 jdolecek 32 1.1.18.2 jdolecek #ifndef _RISCV_MUTEX_H_ 33 1.1.18.2 jdolecek #define _RISCV_MUTEX_H_ 34 1.1.18.2 jdolecek 35 1.1.18.2 jdolecek #ifndef __MUTEX_PRIVATE 36 1.1.18.2 jdolecek 37 1.1.18.2 jdolecek struct kmutex { 38 1.1.18.2 jdolecek uintptr_t mtx_pad1; 39 1.1.18.2 jdolecek }; 40 1.1.18.2 jdolecek 41 1.1.18.2 jdolecek #else /* __MUTEX_PRIVATE */ 42 1.1.18.2 jdolecek 43 1.1.18.2 jdolecek #include <sys/param.h> 44 1.1.18.2 jdolecek 45 1.1.18.2 jdolecek struct kmutex { 46 1.1.18.2 jdolecek volatile uintptr_t mtx_owner; 47 1.1.18.2 jdolecek }; 48 1.1.18.2 jdolecek 49 1.1.18.2 jdolecek #ifdef _LP64 50 1.1.18.2 jdolecek #define MTX_ASMOP_SFX ".d" // doubleword atomic op 51 1.1.18.2 jdolecek #else 52 1.1.18.2 jdolecek #define MTX_ASMOP_SFX ".w" // word atomic op 53 1.1.18.2 jdolecek #endif 54 1.1.18.2 jdolecek 55 1.1.18.2 jdolecek #define MTX_LOCK __BIT(8) // just one bit 56 1.1.18.2 jdolecek #define MTX_IPL __BITS(7,4) // only need 4 bits 57 1.1.18.2 jdolecek 58 1.1.18.2 jdolecek #undef MUTEX_SPIN_IPL // override <sys/mutex.h> 59 1.1.18.2 jdolecek #define MUTEX_SPIN_IPL(a) riscv_mutex_spin_ipl(a) 60 1.1.18.2 jdolecek #define MUTEX_INITIALIZE_SPIN_IPL(a,b) riscv_mutex_initialize_spin_ipl(a,b) 61 1.1.18.2 jdolecek #define MUTEX_SPINBIT_LOCK_INIT(a) riscv_mutex_spinbit_lock_init(a) 62 1.1.18.2 jdolecek #define MUTEX_SPINBIT_LOCK_TRY(a) riscv_mutex_spinbit_lock_try(a) 63 1.1.18.2 jdolecek #define MUTEX_SPINBIT_LOCKED_P(a) riscv_mutex_spinbit_locked_p(a) 64 1.1.18.2 jdolecek #define MUTEX_SPINBIT_LOCK_UNLOCK(a) riscv_mutex_spinbit_lock_unlock(a) 65 1.1.18.2 jdolecek 66 1.1.18.2 jdolecek static inline ipl_cookie_t 67 1.1.18.2 jdolecek riscv_mutex_spin_ipl(kmutex_t *__mtx) 68 1.1.18.2 jdolecek { 69 1.1.18.2 jdolecek return (ipl_cookie_t){._spl = __SHIFTOUT(__mtx->mtx_owner, MTX_IPL)}; 70 1.1.18.2 jdolecek } 71 1.1.18.2 jdolecek 72 1.1.18.2 jdolecek static inline void 73 1.1.18.2 jdolecek riscv_mutex_initialize_spin_ipl(kmutex_t *__mtx, int ipl) 74 1.1.18.2 jdolecek { 75 1.1.18.2 jdolecek __mtx->mtx_owner = (__mtx->mtx_owner & ~MTX_IPL) 76 1.1.18.2 jdolecek | __SHIFTIN(ipl, MTX_IPL); 77 1.1.18.2 jdolecek } 78 1.1.18.2 jdolecek 79 1.1.18.2 jdolecek static inline void 80 1.1.18.2 jdolecek riscv_mutex_spinbit_lock_init(kmutex_t *__mtx) 81 1.1.18.2 jdolecek { 82 1.1.18.2 jdolecek __mtx->mtx_owner &= ~MTX_LOCK; 83 1.1.18.2 jdolecek } 84 1.1.18.2 jdolecek 85 1.1.18.2 jdolecek static inline bool 86 1.1.18.2 jdolecek riscv_mutex_spinbit_locked_p(kmutex_t *__mtx) 87 1.1.18.2 jdolecek { 88 1.1.18.2 jdolecek return (__mtx->mtx_owner & MTX_LOCK) != 0; 89 1.1.18.2 jdolecek } 90 1.1.18.2 jdolecek 91 1.1.18.2 jdolecek static inline bool 92 1.1.18.2 jdolecek riscv_mutex_spinbit_lock_try(kmutex_t *__mtx) 93 1.1.18.2 jdolecek { 94 1.1.18.2 jdolecek uintptr_t __old; 95 1.1.18.2 jdolecek __asm __volatile( 96 1.1.18.2 jdolecek "amoor" MTX_ASMOP_SFX ".aq\t%0, %1, (%2)" 97 1.1.18.2 jdolecek : "=r"(__old) 98 1.1.18.2 jdolecek : "r"(MTX_LOCK), "r"(__mtx)); 99 1.1.18.2 jdolecek return (__old & MTX_LOCK) == 0; 100 1.1.18.2 jdolecek } 101 1.1.18.2 jdolecek 102 1.1.18.2 jdolecek static inline void 103 1.1.18.2 jdolecek riscv_mutex_spinbit_lock_unlock(kmutex_t *__mtx) 104 1.1.18.2 jdolecek { 105 1.1.18.2 jdolecek __asm __volatile( 106 1.1.18.2 jdolecek "amoand" MTX_ASMOP_SFX ".rl\tx0, %0, (%1)" 107 1.1.18.2 jdolecek :: "r"(~MTX_LOCK), "r"(__mtx)); 108 1.1.18.2 jdolecek } 109 1.1.18.2 jdolecek 110 1.1.18.2 jdolecek #if 0 111 1.1.18.2 jdolecek #define __HAVE_MUTEX_STUBS 1 112 1.1.18.2 jdolecek #define __HAVE_SPIN_MUTEX_STUBS 1 113 1.1.18.2 jdolecek #endif 114 1.1.18.2 jdolecek #define __HAVE_SIMPLE_MUTEXES 1 115 1.1.18.2 jdolecek 116 1.1.18.2 jdolecek /* 117 1.1.18.2 jdolecek * MUTEX_RECEIVE: no memory barrier required; we're synchronizing against 118 1.1.18.2 jdolecek * interrupts, not multiple processors. 119 1.1.18.2 jdolecek */ 120 1.1.18.2 jdolecek #ifdef MULTIPROCESSOR 121 1.1.18.2 jdolecek #define MUTEX_RECEIVE(mtx) membar_consumer() 122 1.1.18.2 jdolecek #else 123 1.1.18.2 jdolecek #define MUTEX_RECEIVE(mtx) /* nothing */ 124 1.1.18.2 jdolecek #endif 125 1.1.18.2 jdolecek 126 1.1.18.2 jdolecek /* 127 1.1.18.2 jdolecek * MUTEX_GIVE: no memory barrier required; same reason. 128 1.1.18.2 jdolecek */ 129 1.1.18.2 jdolecek #ifdef MULTIPROCESSOR 130 1.1.18.2 jdolecek #define MUTEX_GIVE(mtx) membar_producer() 131 1.1.18.2 jdolecek #else 132 1.1.18.2 jdolecek #define MUTEX_GIVE(mtx) /* nothing */ 133 1.1.18.2 jdolecek #endif 134 1.1.18.2 jdolecek 135 1.1.18.2 jdolecek #define MUTEX_CAS(p, o, n) \ 136 1.1.18.2 jdolecek (atomic_cas_ulong((volatile unsigned long *)(p), (o), (n)) == (o)) 137 1.1.18.2 jdolecek 138 1.1.18.2 jdolecek #endif /* __MUTEX_PRIVATE */ 139 1.1.18.2 jdolecek 140 1.1.18.2 jdolecek #endif /* _RISCV_MUTEX_H_ */ 141
Indexes created Fri Oct 03 02:09:57 GMT 2025