1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #ifndef _SYS_MUTEX_IMPL_H 27 #define _SYS_MUTEX_IMPL_H 28 29 #pragma ident "%Z%%M% %I% %E% SMI" 30 31 #ifndef _ASM 32 #include <sys/types.h> 33 #include <sys/machlock.h> 34 #endif 35 36 #ifdef __cplusplus 37 extern "C" { 38 #endif 39 40 #ifndef _ASM 41 42 /* 43 * mutex_enter() assumes that the mutex is adaptive and tries to grab the 44 * lock by doing a atomic compare and exchange on the first word of the mutex. 45 * If the compare and exchange fails, it means that either (1) the lock is a 46 * spin lock, or (2) the lock is adaptive but already held. 47 * mutex_vector_enter() distinguishes these cases by looking at the mutex 48 * type, which is encoded in the low-order bits of the owner field. 49 */ 50 typedef union mutex_impl { 51 /* 52 * Adaptive mutex. 53 */ 54 struct adaptive_mutex { 55 uintptr_t _m_owner; /* 0-3/0-7 owner and waiters bit */ 56 #ifndef _LP64 57 uintptr_t _m_filler; /* 4-7 unused */ 58 #endif 59 } m_adaptive; 60 61 /* 62 * Spin Mutex. 63 */ 64 struct spin_mutex { 65 lock_t m_dummylock; /* 0 dummy lock (always set) */ 66 lock_t m_spinlock; /* 1 real lock */ 67 ushort_t m_filler; /* 2-3 unused */ 68 ushort_t m_oldspl; /* 4-5 old pil value */ 69 ushort_t m_minspl; /* 6-7 min pil val if lock held */ 70 } m_spin; 71 72 } mutex_impl_t; 73 74 #define m_owner m_adaptive._m_owner 75 76 #define MUTEX_ALIGN _LONG_ALIGNMENT 77 #define MUTEX_ALIGN_WARNINGS 10 /* num of warnings to issue */ 78 79 #define MUTEX_WAITERS 0x1 80 #define MUTEX_DEAD 0x6 81 #define MUTEX_THREAD (-0x8) 82 83 #define MUTEX_OWNER(lp) ((kthread_id_t)((lp)->m_owner & MUTEX_THREAD)) 84 #define MUTEX_NO_OWNER ((kthread_id_t)NULL) 85 86 #define MUTEX_SET_WAITERS(lp) \ 87 { \ 88 uintptr_t old; \ 89 while ((old = (lp)->m_owner) != 0 && \ 90 casip(&(lp)->m_owner, old, old | MUTEX_WAITERS) != old) \ 91 continue; \ 92 } 93 94 #define MUTEX_HAS_WAITERS(lp) ((lp)->m_owner & MUTEX_WAITERS) 95 #define MUTEX_CLEAR_LOCK_AND_WAITERS(lp) (lp)->m_owner = 0 96 97 #define MUTEX_SET_TYPE(lp, type) 98 #define MUTEX_TYPE_ADAPTIVE(lp) (((lp)->m_owner & MUTEX_DEAD) == 0) 99 #define MUTEX_TYPE_SPIN(lp) ((lp)->m_spin.m_dummylock == LOCK_HELD_VALUE) 100 101 #define MUTEX_DESTROY(lp) \ 102 (lp)->m_owner = ((uintptr_t)curthread | MUTEX_DEAD) 103 /* mutex backoff delay macro and constants */ 104 #define MUTEX_BACKOFF_BASE 1 105 #define MUTEX_BACKOFF_SHIFT 2 106 #define MUTEX_CAP_FACTOR 64 107 #define MUTEX_DELAY() { \ 108 mutex_delay(); \ 109 SMT_PAUSE(); \ 110 } 111 112 /* low overhead clock read */ 113 #define MUTEX_GETTICK() tsc_read() 114 extern void null_xcall(void); 115 #define MUTEX_SYNC() { \ 116 cpuset_t set; \ 117 CPUSET_ALL(set); \ 118 xc_call(0, 0, 0, X_CALL_HIPRI, set, \ 119 (xc_func_t)null_xcall); \ 120 } 121 122 extern int mutex_adaptive_tryenter(mutex_impl_t *); 123 extern void *mutex_owner_running(mutex_impl_t *); 124 125 #else /* _ASM */ 126 127 #define MUTEX_THREAD -0x8 128 129 #endif /* _ASM */ 130 131 #ifdef __cplusplus 132 } 133 #endif 134 135 #endif /* _SYS_MUTEX_IMPL_H */ 136