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 2009 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 #ifndef _ASM 30 #include <sys/types.h> 31 #include <sys/machlock.h> 32 #endif 33 34 #ifdef __cplusplus 35 extern "C" { 36 #endif 37 38 #ifndef _ASM 39 40 /* 41 * mutex_enter() assumes that the mutex is adaptive and tries to grab the 42 * lock by doing a atomic compare and exchange on the first word of the mutex. 43 * If the compare and exchange fails, it means that either (1) the lock is a 44 * spin lock, or (2) the lock is adaptive but already held. 45 * mutex_vector_enter() distinguishes these cases by looking at the mutex 46 * type, which is encoded in the low-order bits of the owner field. 47 */ 48 typedef union mutex_impl { 49 /* 50 * Adaptive mutex. 51 */ 52 struct adaptive_mutex { 53 uintptr_t _m_owner; /* 0-3/0-7 owner and waiters bit */ 54 #ifndef _LP64 55 uintptr_t _m_filler; /* 4-7 unused */ 56 #endif 57 } m_adaptive; 58 59 /* 60 * Spin Mutex. 61 */ 62 struct spin_mutex { 63 lock_t m_dummylock; /* 0 dummy lock (always set) */ 64 lock_t m_spinlock; /* 1 real lock */ 65 ushort_t m_filler; /* 2-3 unused */ 66 ushort_t m_oldspl; /* 4-5 old pil value */ 67 ushort_t m_minspl; /* 6-7 min pil val if lock held */ 68 } m_spin; 69 70 } mutex_impl_t; 71 72 #define m_owner m_adaptive._m_owner 73 74 #define MUTEX_ALIGN _LONG_ALIGNMENT 75 #define MUTEX_ALIGN_WARNINGS 10 /* num of warnings to issue */ 76 77 #define MUTEX_WAITERS 0x1 78 #define MUTEX_DEAD 0x6 79 #define MUTEX_THREAD (-0x8) 80 81 #define MUTEX_OWNER(lp) ((kthread_id_t)((lp)->m_owner & MUTEX_THREAD)) 82 #define MUTEX_NO_OWNER ((kthread_id_t)NULL) 83 84 #define MUTEX_SET_WAITERS(lp) \ 85 { \ 86 uintptr_t old; \ 87 while ((old = (lp)->m_owner) != 0 && \ 88 casip(&(lp)->m_owner, old, old | MUTEX_WAITERS) != old) \ 89 continue; \ 90 } 91 92 #define MUTEX_HAS_WAITERS(lp) ((lp)->m_owner & MUTEX_WAITERS) 93 #define MUTEX_CLEAR_LOCK_AND_WAITERS(lp) (lp)->m_owner = 0 94 95 #define MUTEX_SET_TYPE(lp, type) 96 #define MUTEX_TYPE_ADAPTIVE(lp) (((lp)->m_owner & MUTEX_DEAD) == 0) 97 #define MUTEX_TYPE_SPIN(lp) ((lp)->m_spin.m_dummylock == LOCK_HELD_VALUE) 98 99 #define MUTEX_DESTROY(lp) \ 100 (lp)->m_owner = ((uintptr_t)curthread | MUTEX_DEAD) 101 /* mutex backoff delay macro and constants */ 102 #define MUTEX_BACKOFF_BASE 1 103 #define MUTEX_BACKOFF_SHIFT 2 104 #define MUTEX_CAP_FACTOR 64 105 #define MUTEX_DELAY() { \ 106 mutex_delay(); \ 107 SMT_PAUSE(); \ 108 } 109 110 /* low overhead clock read */ 111 #define MUTEX_GETTICK() tsc_read() 112 extern void null_xcall(void); 113 #define MUTEX_SYNC() { \ 114 cpuset_t set; \ 115 CPUSET_ALL(set); \ 116 xc_call(0, 0, 0, CPUSET2BV(set), \ 117 (xc_func_t)null_xcall); \ 118 } 119 120 extern int mutex_adaptive_tryenter(mutex_impl_t *); 121 extern void *mutex_owner_running(mutex_impl_t *); 122 123 #else /* _ASM */ 124 125 #define MUTEX_THREAD -0x8 126 127 #endif /* _ASM */ 128 129 #ifdef __cplusplus 130 } 131 #endif 132 133 #endif /* _SYS_MUTEX_IMPL_H */ 134