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 /* 23 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #ifndef _SYS_CONDVAR_IMPL_H 28 #define _SYS_CONDVAR_IMPL_H 29 30 #pragma ident "%Z%%M% %I% %E% SMI" 31 32 /* 33 * Implementation-private definitions for condition variables 34 */ 35 36 #ifndef _ASM 37 #include <sys/types.h> 38 #include <sys/thread.h> 39 #endif /* _ASM */ 40 41 #ifdef __cplusplus 42 extern "C" { 43 #endif 44 45 #ifndef _ASM 46 47 /* 48 * Condtion variables. 49 */ 50 51 typedef struct _condvar_impl { 52 ushort_t cv_waiters; 53 } condvar_impl_t; 54 55 #define CV_HAS_WAITERS(cvp) (((condvar_impl_t *)(cvp))->cv_waiters != 0) 56 57 #endif /* _ASM */ 58 59 60 typedef struct cvwaitlock_s { 61 kmutex_t cvw_lock; 62 kcondvar_t cvw_waiter; 63 int cvw_refcnt; 64 } cvwaitlock_t; 65 66 67 #define CVW_INIT(_c) { \ 68 mutex_init(&(_c)->cvw_lock, NULL, MUTEX_DRIVER, NULL); \ 69 cv_init(&(_c)->cvw_waiter, NULL, CV_DRIVER, NULL); \ 70 (_c)->cvw_refcnt = 0; \ 71 } 72 73 #define CVW_ENTER_READ(_c) { \ 74 mutex_enter(&(_c)->cvw_lock); \ 75 while ((_c)->cvw_refcnt < 0) \ 76 cv_wait(&((_c)->cvw_waiter), &(_c)->cvw_lock); \ 77 (_c)->cvw_refcnt++; \ 78 mutex_exit(&(_c)->cvw_lock); \ 79 } 80 81 #define CVW_ENTER_WRITE(_c) { \ 82 mutex_enter(&(_c)->cvw_lock); \ 83 while ((_c)->cvw_refcnt != 0) \ 84 cv_wait(&((_c)->cvw_waiter), &(_c)->cvw_lock); \ 85 (_c)->cvw_refcnt = -1; \ 86 mutex_exit(&(_c)->cvw_lock); \ 87 } 88 89 #define CVW_EXIT_READ(_c) { \ 90 mutex_enter(&(_c)->cvw_lock); \ 91 ASSERT((_c)->cvw_refcnt > 0); \ 92 if ((--((_c)->cvw_refcnt)) == 0) \ 93 cv_broadcast(&(_c)->cvw_waiter); \ 94 mutex_exit(&(_c)->cvw_lock); \ 95 } 96 97 #define CVW_EXIT_WRITE(_c) { \ 98 mutex_enter(&(_c)->cvw_lock); \ 99 ASSERT((_c)->cvw_refcnt == -1); \ 100 (_c)->cvw_refcnt = 0; \ 101 cv_broadcast(&(_c)->cvw_waiter); \ 102 mutex_exit(&(_c)->cvw_lock); \ 103 } 104 105 #ifdef __cplusplus 106 } 107 #endif 108 109 #endif /* _SYS_CONDVAR_IMPL_H */ 110