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 2007 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 #pragma ident "%Z%%M% %I% %E% SMI"
27
28 /*
29 * routines to wait and wake up a client waiting on a list for a
30 * name service request
31 */
32 #include "cache.h"
33
34 int
nscd_wait(nsc_ctx_t * ctx,nsc_db_t * nscdb,nsc_entry_t * entry)35 nscd_wait(nsc_ctx_t *ctx, nsc_db_t *nscdb, nsc_entry_t *entry)
36 {
37 waiter_t mywait;
38 waiter_t *wchan = &nscdb->db_wait;
39
40 (void) cond_init(&(mywait.w_waitcv), USYNC_THREAD, 0);
41 mywait.w_key = entry;
42 mywait.w_signaled = 0;
43 mywait.w_next = wchan->w_next;
44 mywait.w_prev = wchan;
45 if (mywait.w_next)
46 mywait.w_next->w_prev = &mywait;
47 wchan->w_next = &mywait;
48
49 (void) mutex_lock(&ctx->stats_mutex);
50 ctx->stats.wait_count++;
51 (void) mutex_unlock(&ctx->stats_mutex);
52
53 while (!mywait.w_signaled)
54 (void) cond_wait(&(mywait.w_waitcv), &nscdb->db_mutex);
55 if (mywait.w_prev)
56 mywait.w_prev->w_next = mywait.w_next;
57 if (mywait.w_next)
58 mywait.w_next->w_prev = mywait.w_prev;
59 return (0);
60 }
61
62 int
nscd_signal(nsc_ctx_t * ctx,nsc_db_t * nscdb,nsc_entry_t * entry)63 nscd_signal(nsc_ctx_t *ctx, nsc_db_t *nscdb, nsc_entry_t *entry)
64 {
65 int c = 0;
66 waiter_t *wchan = &nscdb->db_wait;
67 waiter_t *tmp = wchan->w_next;
68
69 while (tmp) {
70 if (tmp->w_key == entry) {
71 (void) cond_signal(&(tmp->w_waitcv));
72 tmp->w_signaled = 1;
73
74 (void) mutex_lock(&ctx->stats_mutex);
75 ctx->stats.wait_count--;
76 (void) mutex_unlock(&ctx->stats_mutex);
77 c++;
78 }
79 tmp = tmp->w_next;
80 }
81
82 return (c);
83 }
84