mutex.h revision b819cea2f73f98c5662230cc9affc8cc84f77fcf
/*
* 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 (c) 1991, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright 2013 Nexenta Systems, Inc. All rights reserved.
*/
#ifndef _SYS_MUTEX_H
#define _SYS_MUTEX_H
#include <sys/synch.h> /* lwp_mutex_t */
#ifdef __cplusplus
extern "C" {
#endif
/*
* Public interface to mutual exclusion locks. See mutex(9F) for details.
*
* The basic mutex type is MUTEX_ADAPTIVE, which is expected to be used
* in almost all of the kernel. MUTEX_SPIN provides interrupt blocking
* and must be used in interrupt handlers above LOCK_LEVEL. The iblock
* cookie argument to mutex_init() encodes the interrupt level to block.
* The iblock cookie must be NULL for adaptive locks.
*
* MUTEX_DEFAULT is the type usually specified (except in drivers) to
* mutex_init(). It is identical to MUTEX_ADAPTIVE.
*
* MUTEX_DRIVER is always used by drivers. mutex_init() converts this to
* either MUTEX_ADAPTIVE or MUTEX_SPIN depending on the iblock cookie.
*
* Mutex statistics can be gathered on the fly, without rebooting or
* recompiling the kernel, via the lockstat driver (lockstat(7D)).
*/
typedef enum {
MUTEX_ADAPTIVE = 0, /* spin if owner is running, otherwise block */
MUTEX_SPIN = 1, /* block interrupts and spin */
MUTEX_DRIVER = 4, /* driver (DDI) mutex */
MUTEX_DEFAULT = 6 /* kernel default mutex */
} kmutex_type_t;
struct _kmutex {
lwp_mutex_t m_lock;
void *m_owner;
};
typedef struct _kmutex kmutex_t;
#if defined(_KERNEL) || defined(_FAKE_KERNEL)
/* See the real sys/mutex.h */
typedef struct pad_mutex {
kmutex_t pad_mutex;
#ifdef _LP64
char pad_pad[64 - sizeof (kmutex_t)];
#endif
} pad_mutex_t;
#endif /* _KERNEL */
#define MUTEX_HELD(x) (mutex_owned(x))
#define MUTEX_NOT_HELD(x) (!mutex_owned(x) || panicstr)
/*
* We're simulating the kernel mutex API here, and the
* user-level has a different signature, so rename.
*/
#define mutex_init kmutex_init
#define mutex_destroy kmutex_destroy
extern void kmutex_init(kmutex_t *, char *, kmutex_type_t, void *);
extern void kmutex_destroy(kmutex_t *);
extern void mutex_enter(kmutex_t *);
extern int mutex_tryenter(kmutex_t *);
extern void mutex_exit(kmutex_t *);
extern int mutex_owned(const kmutex_t *);
extern void *mutex_owner(const kmutex_t *);
#ifdef __cplusplus
}
#endif
#endif /* _SYS_MUTEX_H */