/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2008 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ #ifndef _SYS_MUTEX_IMPL_H #define _SYS_MUTEX_IMPL_H #pragma ident "%Z%%M% %I% %E% SMI" #ifndef _ASM #include #include #endif #ifdef __cplusplus extern "C" { #endif #define MUTEX_THREAD (-0x8) #ifndef _ASM /* * mutex_enter() assumes that the mutex is adaptive and tries to grab the * lock by doing a cas on the first word of the mutex. If the cas fails, * it means that either (1) the lock is a spin lock, or (2) the lock is * adaptive but already held. mutex_vector_enter() distinguishes these * cases by looking at the mutex type, which is encoded in the low-order * bits of the owner field. */ typedef union mutex_impl { /* * Adaptive mutex. */ struct adaptive_mutex { uintptr_t _m_owner; /* 0-3/0-7 owner and waiters bit */ } m_adaptive; /* * Spin Mutex. */ struct spin_mutex { ushort_t m_oldspl; /* 0-1 old %pil value */ ushort_t m_minspl; /* 2-3 min %pil val if lock held */ ushort_t m_filler; /* 4-5 unused */ lock_t m_spinlock; /* 6 real lock */ lock_t m_dummylock; /* 7 dummy lock (always set) */ } m_spin; } mutex_impl_t; #define m_owner m_adaptive._m_owner #define MUTEX_WAITERS 0x1 #define MUTEX_DEAD 0x6 #define MUTEX_THREAD (-0x8) #define MUTEX_OWNER(lp) ((kthread_id_t)((lp)->m_owner & MUTEX_THREAD)) #define MUTEX_NO_OWNER ((kthread_id_t)NULL) #define MUTEX_SET_WAITERS(lp) \ { \ uintptr_t old; \ while ((old = (lp)->m_owner) != 0 && \ casip(&(lp)->m_owner, old, old | MUTEX_WAITERS) != old) \ continue; \ } #define MUTEX_HAS_WAITERS(lp) ((lp)->m_owner & MUTEX_WAITERS) #define MUTEX_CLEAR_LOCK_AND_WAITERS(lp) (lp)->m_owner = 0 #define MUTEX_SET_TYPE(lp, type) #define MUTEX_TYPE_ADAPTIVE(lp) (((lp)->m_owner & MUTEX_DEAD) == 0) #define MUTEX_TYPE_SPIN(lp) ((lp)->m_spin.m_dummylock == LOCK_HELD_VALUE) #define MUTEX_DESTROY(lp) \ (lp)->m_owner = ((uintptr_t)curthread | MUTEX_DEAD) #define MUTEX_BACKOFF_BASE 1 #define MUTEX_BACKOFF_SHIFT 1 #define MUTEX_CAP_FACTOR 8 #define MUTEX_DELAY() { \ mutex_delay(); \ } /* low-overhead clock read */ extern u_longlong_t gettick(void); #define MUTEX_GETTICK() gettick() extern void null_xcall(void); #define MUTEX_SYNC() xc_all((xcfunc_t *)null_xcall, 0, 0) extern void cas_delay(void *); extern void rdccr_delay(void); extern int mutex_adaptive_tryenter(mutex_impl_t *); extern void *mutex_owner_running(mutex_impl_t *); #endif /* _ASM */ #ifdef __cplusplus } #endif #endif /* _SYS_MUTEX_IMPL_H */