1*0Sstevel@tonic-gate /* 2*0Sstevel@tonic-gate * CDDL HEADER START 3*0Sstevel@tonic-gate * 4*0Sstevel@tonic-gate * The contents of this file are subject to the terms of the 5*0Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only 6*0Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance 7*0Sstevel@tonic-gate * with the License. 8*0Sstevel@tonic-gate * 9*0Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10*0Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 11*0Sstevel@tonic-gate * See the License for the specific language governing permissions 12*0Sstevel@tonic-gate * and limitations under the License. 13*0Sstevel@tonic-gate * 14*0Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 15*0Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16*0Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 17*0Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 18*0Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 19*0Sstevel@tonic-gate * 20*0Sstevel@tonic-gate * CDDL HEADER END 21*0Sstevel@tonic-gate */ 22*0Sstevel@tonic-gate /* 23*0Sstevel@tonic-gate * Copyright 2004 Sun Microsystems, Inc. All rights reserved. 24*0Sstevel@tonic-gate * Use is subject to license terms. 25*0Sstevel@tonic-gate */ 26*0Sstevel@tonic-gate 27*0Sstevel@tonic-gate #ifndef _SYS_MUTEX_IMPL_H 28*0Sstevel@tonic-gate #define _SYS_MUTEX_IMPL_H 29*0Sstevel@tonic-gate 30*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI" 31*0Sstevel@tonic-gate 32*0Sstevel@tonic-gate #ifndef _ASM 33*0Sstevel@tonic-gate #include <sys/types.h> 34*0Sstevel@tonic-gate #include <sys/machlock.h> 35*0Sstevel@tonic-gate #endif 36*0Sstevel@tonic-gate 37*0Sstevel@tonic-gate #ifdef __cplusplus 38*0Sstevel@tonic-gate extern "C" { 39*0Sstevel@tonic-gate #endif 40*0Sstevel@tonic-gate 41*0Sstevel@tonic-gate #ifndef _ASM 42*0Sstevel@tonic-gate 43*0Sstevel@tonic-gate /* 44*0Sstevel@tonic-gate * mutex_enter() assumes that the mutex is adaptive and tries to grab the 45*0Sstevel@tonic-gate * lock by doing a atomic compare and exchange on the first word of the mutex. 46*0Sstevel@tonic-gate * If the compare and exchange fails, it means that either (1) the lock is a 47*0Sstevel@tonic-gate * spin lock, or (2) the lock is adaptive but already held. 48*0Sstevel@tonic-gate * mutex_vector_enter() distinguishes these cases by looking at the mutex 49*0Sstevel@tonic-gate * type, which is encoded in the low-order bits of the owner field. 50*0Sstevel@tonic-gate */ 51*0Sstevel@tonic-gate typedef union mutex_impl { 52*0Sstevel@tonic-gate /* 53*0Sstevel@tonic-gate * Adaptive mutex. 54*0Sstevel@tonic-gate */ 55*0Sstevel@tonic-gate struct adaptive_mutex { 56*0Sstevel@tonic-gate uintptr_t _m_owner; /* 0-3/0-7 owner and waiters bit */ 57*0Sstevel@tonic-gate #ifndef _LP64 58*0Sstevel@tonic-gate uintptr_t _m_filler; /* 4-7 unused */ 59*0Sstevel@tonic-gate #endif 60*0Sstevel@tonic-gate } m_adaptive; 61*0Sstevel@tonic-gate 62*0Sstevel@tonic-gate /* 63*0Sstevel@tonic-gate * Spin Mutex. 64*0Sstevel@tonic-gate */ 65*0Sstevel@tonic-gate struct spin_mutex { 66*0Sstevel@tonic-gate lock_t m_dummylock; /* 0 dummy lock (always set) */ 67*0Sstevel@tonic-gate lock_t m_spinlock; /* 1 real lock */ 68*0Sstevel@tonic-gate ushort_t m_filler; /* 2-3 unused */ 69*0Sstevel@tonic-gate ushort_t m_oldspl; /* 4-5 old pil value */ 70*0Sstevel@tonic-gate ushort_t m_minspl; /* 6-7 min pil val if lock held */ 71*0Sstevel@tonic-gate } m_spin; 72*0Sstevel@tonic-gate 73*0Sstevel@tonic-gate } mutex_impl_t; 74*0Sstevel@tonic-gate 75*0Sstevel@tonic-gate #define m_owner m_adaptive._m_owner 76*0Sstevel@tonic-gate 77*0Sstevel@tonic-gate #define MUTEX_WAITERS 0x1 78*0Sstevel@tonic-gate #define MUTEX_DEAD 0x6 79*0Sstevel@tonic-gate #define MUTEX_THREAD (-0x8) 80*0Sstevel@tonic-gate 81*0Sstevel@tonic-gate #define MUTEX_OWNER(lp) ((kthread_id_t)((lp)->m_owner & MUTEX_THREAD)) 82*0Sstevel@tonic-gate #define MUTEX_NO_OWNER ((kthread_id_t)NULL) 83*0Sstevel@tonic-gate 84*0Sstevel@tonic-gate #define MUTEX_SET_WAITERS(lp) \ 85*0Sstevel@tonic-gate { \ 86*0Sstevel@tonic-gate uintptr_t old; \ 87*0Sstevel@tonic-gate while ((old = (lp)->m_owner) != 0 && \ 88*0Sstevel@tonic-gate casip(&(lp)->m_owner, old, old | MUTEX_WAITERS) != old) \ 89*0Sstevel@tonic-gate continue; \ 90*0Sstevel@tonic-gate } 91*0Sstevel@tonic-gate 92*0Sstevel@tonic-gate #define MUTEX_HAS_WAITERS(lp) ((lp)->m_owner & MUTEX_WAITERS) 93*0Sstevel@tonic-gate #define MUTEX_CLEAR_LOCK_AND_WAITERS(lp) (lp)->m_owner = 0 94*0Sstevel@tonic-gate 95*0Sstevel@tonic-gate #define MUTEX_SET_TYPE(lp, type) 96*0Sstevel@tonic-gate #define MUTEX_TYPE_ADAPTIVE(lp) (((lp)->m_owner & MUTEX_DEAD) == 0) 97*0Sstevel@tonic-gate #define MUTEX_TYPE_SPIN(lp) ((lp)->m_spin.m_dummylock == LOCK_HELD_VALUE) 98*0Sstevel@tonic-gate 99*0Sstevel@tonic-gate #define MUTEX_DESTROY(lp) \ 100*0Sstevel@tonic-gate (lp)->m_owner = ((uintptr_t)curthread | MUTEX_DEAD) 101*0Sstevel@tonic-gate 102*0Sstevel@tonic-gate extern int mutex_adaptive_tryenter(mutex_impl_t *); 103*0Sstevel@tonic-gate 104*0Sstevel@tonic-gate #endif /* _ASM */ 105*0Sstevel@tonic-gate 106*0Sstevel@tonic-gate #ifdef __cplusplus 107*0Sstevel@tonic-gate } 108*0Sstevel@tonic-gate #endif 109*0Sstevel@tonic-gate 110*0Sstevel@tonic-gate #endif /* _SYS_MUTEX_IMPL_H */ 111