1 /* $NetBSD: rf_mcpair.c,v 1.12 2003/12/30 21:59:03 oster 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 1.12 2003/12/30 21:59:03 oster 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 46 #include <sys/pool.h> 47 #include <sys/proc.h> 48 49 static struct pool rf_mcpair_pool; 50 #define RF_MAX_FREE_MCPAIR 128 51 #define RF_MCPAIR_INC 16 52 #define RF_MCPAIR_INITIAL 24 53 54 static void rf_ShutdownMCPair(void *); 55 56 static void 57 rf_ShutdownMCPair(void *ignored) 58 { 59 pool_destroy(&rf_mcpair_pool); 60 } 61 62 int 63 rf_ConfigureMCPair(RF_ShutdownList_t **listp) 64 { 65 int rc; 66 67 pool_init(&rf_mcpair_pool, sizeof(RF_MCPair_t), 0, 0, 0, 68 "rf_mcpair_pl", NULL); 69 pool_sethiwat(&rf_mcpair_pool, RF_MAX_FREE_MCPAIR); 70 pool_prime(&rf_mcpair_pool, RF_MCPAIR_INITIAL); 71 72 rc = rf_ShutdownCreate(listp, rf_ShutdownMCPair, NULL); 73 if (rc) { 74 rf_print_unable_to_add_shutdown(__FILE__, __LINE__, rc); 75 rf_ShutdownMCPair(NULL); 76 return (rc); 77 } 78 79 return (0); 80 } 81 82 RF_MCPair_t * 83 rf_AllocMCPair() 84 { 85 RF_MCPair_t *t; 86 87 t = pool_get(&rf_mcpair_pool, PR_WAITOK); 88 if (t) { 89 simple_lock_init(&t->mutex); 90 t->cond = 0; 91 t->flag = 0; 92 t->next = NULL; 93 } 94 return (t); 95 } 96 97 void 98 rf_FreeMCPair(RF_MCPair_t *t) 99 { 100 pool_put(&rf_mcpair_pool, t); 101 } 102 103 /* the callback function used to wake you up when you use an mcpair to 104 wait for something */ 105 void 106 rf_MCPairWakeupFunc(RF_MCPair_t *mcpair) 107 { 108 RF_LOCK_MUTEX(mcpair->mutex); 109 mcpair->flag = 1; 110 wakeup(&(mcpair->cond)); 111 RF_UNLOCK_MUTEX(mcpair->mutex); 112 } 113