sys/arch/ia64/include/mutex.h

   1 /*      $NetBSD: mutex.h,v 1.3 2008/04/28 20:23:25 martin Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2008 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Takayoshi Kochi.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #ifndef _IA64_MUTEX_H_
  33 #define _IA64_MUTEX_H_
  34
  35 #ifndef __MUTEX_PRIVATE
  36
  37 struct kmutex {
  38         uintptr_t       mtx_pad1;
  39         uint32_t        mtx_pad2[2];
  40 };
  41
  42 #else
  43
  44 struct kmutex {
  45         volatile uintptr_t      mtx_owner;
  46         ipl_cookie_t            mtx_ipl;
  47         __cpu_simple_lock_t     mtx_lock;
  48 };
  49
  50
  51 /* XXX when we implement mutex_enter()/mutex_exit(), uncomment this
  52 #define __HAVE_MUTEX_STUBS              1
  53 */
  54 /* XXX when we implement mutex_spin_enter()/mutex_spin_exit(), uncomment this
  55 #define __HAVE_SPIN_MUTEX_STUBS         1
  56 */
  57 #define __HAVE_SIMPLE_MUTEXES           1
  58
  59 /*
  60  * MUTEX_RECEIVE: no memory barrier required, atomic_cas implies a load fence.
  61  */
  62 #define MUTEX_RECEIVE(mtx)              /* nothing */
  63
  64 /*
  65  * MUTEX_GIVE: no memory barrier required, as _lock_cas() will take care of it.
  66  */
  67 #define MUTEX_GIVE(mtx)                 /* nothing */
  68
  69 #define MUTEX_CAS(ptr, old, new)                \
  70     (atomic_cas_ulong((volatile unsigned long *)(ptr), (old), (new)) == (old))
  71
  72 #endif  /* __MUTEX_PRIVATE */
  73
  74 #endif  /* _IA64_MUTEX_H_ */