xref: /netbsd-src/sys/dev/raidframe/rf_mcpair.c (revision deb6f0161a9109e7de9b519dc8dfb9478668dcdd)
1 /*	$NetBSD: rf_mcpair.c,v 1.24 2011/05/01 01:09:05 mrg Exp $	*/
2 /*
3  * Copyright (c) 1995 Carnegie-Mellon University.
4  * All rights reserved.
5  *
6  * Author: Jim Zelenka
7  *
8  * Permission to use, copy, modify and distribute this software and
9  * its documentation is hereby granted, provided that both the copyright
10  * notice and this permission notice appear in all copies of the
11  * software, derivative works or modified versions, and any portions
12  * thereof, and that both notices appear in supporting documentation.
13  *
14  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
15  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
16  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
17  *
18  * Carnegie Mellon requests users of this software to return to
19  *
20  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
21  *  School of Computer Science
22  *  Carnegie Mellon University
23  *  Pittsburgh PA 15213-3890
24  *
25  * any improvements or extensions that they make and grant Carnegie the
26  * rights to redistribute these changes.
27  */
28 
29 /* rf_mcpair.c
30  * an mcpair is a structure containing a mutex and a condition variable.
31  * it's used to block the current thread until some event occurs.
32  */
33 
34 #include <sys/cdefs.h>
35 __KERNEL_RCSID(0, "$NetBSD: rf_mcpair.c,v 1.24 2011/05/01 01:09:05 mrg Exp $");
36 
37 #include <dev/raidframe/raidframevar.h>
38 
39 #include "rf_archs.h"
40 #include "rf_threadstuff.h"
41 #include "rf_mcpair.h"
42 #include "rf_debugMem.h"
43 #include "rf_general.h"
44 #include "rf_shutdown.h"
45 #include "rf_netbsd.h"
46 
47 #include <sys/pool.h>
48 #include <sys/proc.h>
49 
50 #define RF_MAX_FREE_MCPAIR 128
51 #define RF_MIN_FREE_MCPAIR  24
52 
53 static void rf_ShutdownMCPair(void *);
54 
55 static void
56 rf_ShutdownMCPair(void *ignored)
57 {
58 	pool_destroy(&rf_pools.mcpair);
59 }
60 
61 int
62 rf_ConfigureMCPair(RF_ShutdownList_t **listp)
63 {
64 
65 	rf_pool_init(&rf_pools.mcpair, sizeof(RF_MCPair_t),
66 		     "rf_mcpair_pl", RF_MIN_FREE_MCPAIR, RF_MAX_FREE_MCPAIR);
67 	rf_ShutdownCreate(listp, rf_ShutdownMCPair, NULL);
68 
69 	return (0);
70 }
71 
72 RF_MCPair_t *
73 rf_AllocMCPair(void)
74 {
75 	RF_MCPair_t *t;
76 
77 	t = pool_get(&rf_pools.mcpair, PR_WAITOK);
78 	rf_init_mutex2(t->mutex, IPL_VM);
79 	rf_init_cond2(t->cond, "mcpair");
80 	t->flag = 0;
81 
82 	return (t);
83 }
84 
85 void
86 rf_FreeMCPair(RF_MCPair_t *t)
87 {
88 	rf_destroy_cond2(t->cond);
89 	rf_destroy_mutex2(t->mutex);
90 	pool_put(&rf_pools.mcpair, t);
91 }
92 
93 /* the callback function used to wake you up when you use an mcpair to
94    wait for something */
95 void
96 rf_MCPairWakeupFunc(RF_MCPair_t *mcpair)
97 {
98 	RF_LOCK_MCPAIR(mcpair);
99 	mcpair->flag = 1;
100 	rf_broadcast_cond2(mcpair->cond);
101 	RF_UNLOCK_MCPAIR(mcpair);
102 }
103