subr_callback.c revision 1.4.2.2
1 1.4.2.2 yamt /* $NetBSD: subr_callback.c,v 1.4.2.2 2006/06/26 12:52:56 yamt Exp $ */ 2 1.4.2.2 yamt 3 1.4.2.2 yamt /*- 4 1.4.2.2 yamt * Copyright (c)2006 YAMAMOTO Takashi, 5 1.4.2.2 yamt * All rights reserved. 6 1.4.2.2 yamt * 7 1.4.2.2 yamt * Redistribution and use in source and binary forms, with or without 8 1.4.2.2 yamt * modification, are permitted provided that the following conditions 9 1.4.2.2 yamt * are met: 10 1.4.2.2 yamt * 1. Redistributions of source code must retain the above copyright 11 1.4.2.2 yamt * notice, this list of conditions and the following disclaimer. 12 1.4.2.2 yamt * 2. Redistributions in binary form must reproduce the above copyright 13 1.4.2.2 yamt * notice, this list of conditions and the following disclaimer in the 14 1.4.2.2 yamt * documentation and/or other materials provided with the distribution. 15 1.4.2.2 yamt * 16 1.4.2.2 yamt * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 1.4.2.2 yamt * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 1.4.2.2 yamt * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 1.4.2.2 yamt * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 1.4.2.2 yamt * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 1.4.2.2 yamt * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 1.4.2.2 yamt * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 1.4.2.2 yamt * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 1.4.2.2 yamt * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 1.4.2.2 yamt * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 1.4.2.2 yamt * SUCH DAMAGE. 27 1.4.2.2 yamt */ 28 1.4.2.2 yamt 29 1.4.2.2 yamt #include <sys/cdefs.h> 30 1.4.2.2 yamt __KERNEL_RCSID(0, "$NetBSD: subr_callback.c,v 1.4.2.2 2006/06/26 12:52:56 yamt Exp $"); 31 1.4.2.2 yamt 32 1.4.2.2 yamt #include <sys/param.h> 33 1.4.2.2 yamt #include <sys/systm.h> 34 1.4.2.2 yamt #include <sys/proc.h> 35 1.4.2.2 yamt #include <sys/callback.h> 36 1.4.2.2 yamt 37 1.4.2.2 yamt #define CH_WANT 1 38 1.4.2.2 yamt 39 1.4.2.2 yamt void 40 1.4.2.2 yamt callback_head_init(struct callback_head *ch) 41 1.4.2.2 yamt { 42 1.4.2.2 yamt 43 1.4.2.2 yamt memset(ch, 0, sizeof(struct callback_head)); 44 1.4.2.2 yamt simple_lock_init(&ch->ch_lock); 45 1.4.2.2 yamt TAILQ_INIT(&ch->ch_q); 46 1.4.2.2 yamt #if 0 /* already zero-initialized */ 47 1.4.2.2 yamt ch->ch_next = NULL; 48 1.4.2.2 yamt ch->ch_nentries = 0; 49 1.4.2.2 yamt ch->ch_running = 0; 50 1.4.2.2 yamt ch->ch_flags = 0; 51 1.4.2.2 yamt #endif 52 1.4.2.2 yamt } 53 1.4.2.2 yamt 54 1.4.2.2 yamt void 55 1.4.2.2 yamt callback_register(struct callback_head *ch, struct callback_entry *ce, 56 1.4.2.2 yamt void *obj, int (*fn)(struct callback_entry *, void *, void *)) 57 1.4.2.2 yamt { 58 1.4.2.2 yamt 59 1.4.2.2 yamt ce->ce_func = fn; 60 1.4.2.2 yamt ce->ce_obj = obj; 61 1.4.2.2 yamt simple_lock(&ch->ch_lock); 62 1.4.2.2 yamt TAILQ_INSERT_TAIL(&ch->ch_q, ce, ce_q); 63 1.4.2.2 yamt ch->ch_nentries++; 64 1.4.2.2 yamt simple_unlock(&ch->ch_lock); 65 1.4.2.2 yamt } 66 1.4.2.2 yamt 67 1.4.2.2 yamt void 68 1.4.2.2 yamt callback_unregister(struct callback_head *ch, struct callback_entry *ce) 69 1.4.2.2 yamt { 70 1.4.2.2 yamt 71 1.4.2.2 yamt simple_lock(&ch->ch_lock); 72 1.4.2.2 yamt while (ch->ch_running > 0) { 73 1.4.2.2 yamt ch->ch_flags |= CH_WANT; 74 1.4.2.2 yamt ltsleep(&ch->ch_running, PVM, "recunreg", 0, &ch->ch_lock); 75 1.4.2.2 yamt } 76 1.4.2.2 yamt if (__predict_false(ch->ch_next == ce)) { 77 1.4.2.2 yamt ch->ch_next = TAILQ_NEXT(ce, ce_q); 78 1.4.2.2 yamt } 79 1.4.2.2 yamt TAILQ_REMOVE(&ch->ch_q, ce, ce_q); 80 1.4.2.2 yamt ch->ch_nentries--; 81 1.4.2.2 yamt simple_unlock(&ch->ch_lock); 82 1.4.2.2 yamt } 83 1.4.2.2 yamt 84 1.4.2.2 yamt static int 85 1.4.2.2 yamt callback_runone(struct callback_head *ch, void *arg) 86 1.4.2.2 yamt { 87 1.4.2.2 yamt struct callback_entry *ce; 88 1.4.2.2 yamt int result; 89 1.4.2.2 yamt 90 1.4.2.2 yamt KASSERT(ch->ch_nentries > 0); 91 1.4.2.2 yamt KASSERT(ch->ch_running > 0); 92 1.4.2.2 yamt 93 1.4.2.2 yamt ce = ch->ch_next; 94 1.4.2.2 yamt if (ce == NULL) { 95 1.4.2.2 yamt ce = TAILQ_FIRST(&ch->ch_q); 96 1.4.2.2 yamt } 97 1.4.2.2 yamt KASSERT(ce != NULL); 98 1.4.2.2 yamt result = (*ce->ce_func)(ce, ce->ce_obj, arg); 99 1.4.2.2 yamt ch->ch_next = TAILQ_NEXT(ce, ce_q); 100 1.4.2.2 yamt return result; 101 1.4.2.2 yamt } 102 1.4.2.2 yamt 103 1.4.2.2 yamt static void 104 1.4.2.2 yamt callback_run_enter(struct callback_head *ch) 105 1.4.2.2 yamt { 106 1.4.2.2 yamt 107 1.4.2.2 yamt simple_lock(&ch->ch_lock); 108 1.4.2.2 yamt ch->ch_running++; 109 1.4.2.2 yamt simple_unlock(&ch->ch_lock); 110 1.4.2.2 yamt } 111 1.4.2.2 yamt 112 1.4.2.2 yamt static void 113 1.4.2.2 yamt callback_run_leave(struct callback_head *ch) 114 1.4.2.2 yamt { 115 1.4.2.2 yamt 116 1.4.2.2 yamt simple_lock(&ch->ch_lock); 117 1.4.2.2 yamt KASSERT(ch->ch_running > 0); 118 1.4.2.2 yamt ch->ch_running--; 119 1.4.2.2 yamt if (ch->ch_running == 0 && (ch->ch_flags & CH_WANT) != 0) { 120 1.4.2.2 yamt ch->ch_flags &= ~CH_WANT; 121 1.4.2.2 yamt wakeup(&ch->ch_running); 122 1.4.2.2 yamt } 123 1.4.2.2 yamt simple_unlock(&ch->ch_lock); 124 1.4.2.2 yamt } 125 1.4.2.2 yamt 126 1.4.2.2 yamt int 127 1.4.2.2 yamt callback_run_roundrobin(struct callback_head *ch, void *arg) 128 1.4.2.2 yamt { 129 1.4.2.2 yamt int i; 130 1.4.2.2 yamt int n; 131 1.4.2.2 yamt int result = 0; 132 1.4.2.2 yamt 133 1.4.2.2 yamt callback_run_enter(ch); 134 1.4.2.2 yamt n = ch->ch_nentries; 135 1.4.2.2 yamt for (i = 0; i < n; i++) { 136 1.4.2.2 yamt result = callback_runone(ch, arg); 137 1.4.2.2 yamt if (result != CALLBACK_CHAIN_CONTINUE) { 138 1.4.2.2 yamt break; 139 1.4.2.2 yamt } 140 1.4.2.2 yamt } 141 1.4.2.2 yamt callback_run_leave(ch); 142 1.4.2.2 yamt 143 1.4.2.2 yamt return result; 144 1.4.2.2 yamt } 145
Indexes created Thu Sep 25 08:09:54 GMT 2025