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 (c) 1991-1998 by Sun Microsystems, Inc. 24*0Sstevel@tonic-gate * All rights reserved. 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 an ldstub on byte 0 of the mutex. If the ldstub fails, 46*0Sstevel@tonic-gate * it means that either (1) the lock is a spin lock, or (2) the lock is 47*0Sstevel@tonic-gate * adaptive but already held. mutex_vector_enter() distinguishes these 48*0Sstevel@tonic-gate * cases by looking at the mutex type, which is byte 7 for both types. 49*0Sstevel@tonic-gate * 50*0Sstevel@tonic-gate * Once the lock byte is set for an adaptive lock, the owner is stuffed 51*0Sstevel@tonic-gate * into the remaining 24 bits such that the owner word is 0xff:owner24. 52*0Sstevel@tonic-gate * This works because a thread pointer only has 24 significant bits: the 53*0Sstevel@tonic-gate * upper 3 bits are 111 (since all kernel addresses are above 0xe0000000), 54*0Sstevel@tonic-gate * and the lower 5 bits are zero (because threads are 32-byte aligned). 55*0Sstevel@tonic-gate */ 56*0Sstevel@tonic-gate typedef union mutex_impl { 57*0Sstevel@tonic-gate /* 58*0Sstevel@tonic-gate * Adaptive mutex. 59*0Sstevel@tonic-gate */ 60*0Sstevel@tonic-gate struct adaptive_mutex { 61*0Sstevel@tonic-gate uintptr_t _m_owner; /* 0-3 owner and lock */ 62*0Sstevel@tonic-gate uchar_t _m_waiters; /* 4 are there waiters? */ 63*0Sstevel@tonic-gate uchar_t _m_filler[2]; /* 5-6 unused */ 64*0Sstevel@tonic-gate uchar_t _m_type; /* 7 type */ 65*0Sstevel@tonic-gate } m_adaptive; 66*0Sstevel@tonic-gate 67*0Sstevel@tonic-gate /* 68*0Sstevel@tonic-gate * Spin Mutex. 69*0Sstevel@tonic-gate */ 70*0Sstevel@tonic-gate struct spin_mutex { 71*0Sstevel@tonic-gate lock_t m_dummylock; /* 0 lock (always set) */ 72*0Sstevel@tonic-gate lock_t m_spinlock; /* 1 real lock */ 73*0Sstevel@tonic-gate ushort_t m_oldspl; /* 2-3 old %psr value */ 74*0Sstevel@tonic-gate ushort_t m_minspl; /* 4-5 min PSR_PIL val if lock held */ 75*0Sstevel@tonic-gate uchar_t m_filler; /* 6 unused */ 76*0Sstevel@tonic-gate uchar_t _m_type; /* 7 type */ 77*0Sstevel@tonic-gate } m_spin; 78*0Sstevel@tonic-gate } mutex_impl_t; 79*0Sstevel@tonic-gate 80*0Sstevel@tonic-gate #define m_owner m_adaptive._m_owner 81*0Sstevel@tonic-gate #define m_waiters m_adaptive._m_waiters 82*0Sstevel@tonic-gate #define m_type m_adaptive._m_type 83*0Sstevel@tonic-gate 84*0Sstevel@tonic-gate /* 85*0Sstevel@tonic-gate * Macro to retrieve 32-bit pointer field out of mutex. 86*0Sstevel@tonic-gate * Relies on 32-byte alignment of thread structures. 87*0Sstevel@tonic-gate * Also relies on KERNELBASE (and all thread pointers) 88*0Sstevel@tonic-gate * being above 0xe0000000. 89*0Sstevel@tonic-gate */ 90*0Sstevel@tonic-gate #define MUTEX_OWNER(lp) ((kthread_id_t)((lp)->m_owner << PTR24_LSB)) 91*0Sstevel@tonic-gate #define MUTEX_NO_OWNER ((kthread_id_t)PTR24_BASE) 92*0Sstevel@tonic-gate 93*0Sstevel@tonic-gate #define MUTEX_SET_WAITERS(lp) ((lp)->m_waiters = 1) 94*0Sstevel@tonic-gate #define MUTEX_HAS_WAITERS(lp) ((lp)->m_waiters != 0) 95*0Sstevel@tonic-gate #define MUTEX_CLEAR_LOCK_AND_WAITERS(lp) \ 96*0Sstevel@tonic-gate (lp)->m_waiters = 0, (lp)->m_owner = 0 97*0Sstevel@tonic-gate 98*0Sstevel@tonic-gate #define MUTEX_SET_TYPE(lp, type) (lp)->m_type = (type) 99*0Sstevel@tonic-gate #define MUTEX_TYPE_ADAPTIVE(lp) ((lp)->m_type == MUTEX_ADAPTIVE) 100*0Sstevel@tonic-gate #define MUTEX_TYPE_SPIN(lp) ((lp)->m_type == MUTEX_SPIN) 101*0Sstevel@tonic-gate 102*0Sstevel@tonic-gate #define MUTEX_DESTROY(lp) \ 103*0Sstevel@tonic-gate (lp)->m_type = 0xdd, LOCK_INIT_HELD(&lp->m_spin.m_dummylock) 104*0Sstevel@tonic-gate 105*0Sstevel@tonic-gate #endif /* _ASM */ 106*0Sstevel@tonic-gate 107*0Sstevel@tonic-gate #ifdef __cplusplus 108*0Sstevel@tonic-gate } 109*0Sstevel@tonic-gate #endif 110*0Sstevel@tonic-gate 111*0Sstevel@tonic-gate #endif /* _SYS_MUTEX_IMPL_H */ 112