1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #ifndef _SYS_MUTEX_H 27 #define _SYS_MUTEX_H 28 29 #ifndef _ASM 30 #include <sys/types.h> 31 #endif 32 33 #ifdef __cplusplus 34 extern "C" { 35 #endif 36 37 #ifndef _ASM 38 39 /* 40 * Public interface to mutual exclusion locks. See mutex(9F) for details. 41 * 42 * The basic mutex type is MUTEX_ADAPTIVE, which is expected to be used 43 * in almost all of the kernel. MUTEX_SPIN provides interrupt blocking 44 * and must be used in interrupt handlers above LOCK_LEVEL. The iblock 45 * cookie argument to mutex_init() encodes the interrupt level to block. 46 * The iblock cookie must be NULL for adaptive locks. 47 * 48 * MUTEX_DEFAULT is the type usually specified (except in drivers) to 49 * mutex_init(). It is identical to MUTEX_ADAPTIVE. 50 * 51 * MUTEX_DRIVER is always used by drivers. mutex_init() converts this to 52 * either MUTEX_ADAPTIVE or MUTEX_SPIN depending on the iblock cookie. 53 * 54 * Mutex statistics can be gathered on the fly, without rebooting or 55 * recompiling the kernel, via the lockstat driver (lockstat(7D)). 56 */ 57 typedef enum { 58 MUTEX_ADAPTIVE = 0, /* spin if owner is running, otherwise block */ 59 MUTEX_SPIN = 1, /* block interrupts and spin */ 60 MUTEX_DRIVER = 4, /* driver (DDI) mutex */ 61 MUTEX_DEFAULT = 6 /* kernel default mutex */ 62 } kmutex_type_t; 63 64 typedef struct mutex { 65 #ifdef _LP64 66 void *_opaque[1]; 67 #else 68 void *_opaque[2]; 69 #endif 70 } kmutex_t; 71 72 #ifdef _KERNEL 73 74 #define MUTEX_HELD(x) (mutex_owned(x)) 75 #define MUTEX_NOT_HELD(x) (!mutex_owned(x) || panicstr || quiesce_active) 76 77 extern void mutex_init(kmutex_t *, char *, kmutex_type_t, void *); 78 extern void mutex_destroy(kmutex_t *); 79 extern void mutex_enter(kmutex_t *); 80 extern int mutex_tryenter(kmutex_t *); 81 extern void mutex_exit(kmutex_t *); 82 extern int mutex_owned(const kmutex_t *); 83 extern struct _kthread *mutex_owner(const kmutex_t *); 84 85 extern ushort_t mutex_backoff_base; 86 extern uint_t mutex_backoff_cap; 87 extern ushort_t mutex_cap_factor; 88 extern uchar_t mutex_backoff_shift; 89 extern void (*mutex_lock_delay)(uint_t); 90 extern uint_t (*mutex_lock_backoff)(uint_t); 91 extern void (*mutex_delay)(void); 92 extern void mutex_delay_default(void); 93 extern void mutex_sync(void); 94 95 extern void default_lock_delay(uint_t); 96 extern uint_t default_lock_backoff(uint_t); 97 98 #endif /* _KERNEL */ 99 100 #endif /* _ASM */ 101 102 #ifdef __cplusplus 103 } 104 #endif 105 106 #endif /* _SYS_MUTEX_H */ 107