NetBSD/sys/dev/raidframe/rf_mcpair.c

103 lines
2.5 KiB
C

/* $NetBSD: rf_mcpair.c,v 1.24 2011/05/01 01:09:05 mrg Exp $ */
/*
* Copyright (c) 1995 Carnegie-Mellon University.
* All rights reserved.
*
* Author: Jim Zelenka
*
* Permission to use, copy, modify and distribute this software and
* its documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
* FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*/
/* rf_mcpair.c
* an mcpair is a structure containing a mutex and a condition variable.
* it's used to block the current thread until some event occurs.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: rf_mcpair.c,v 1.24 2011/05/01 01:09:05 mrg Exp $");
#include <dev/raidframe/raidframevar.h>
#include "rf_archs.h"
#include "rf_threadstuff.h"
#include "rf_mcpair.h"
#include "rf_debugMem.h"
#include "rf_general.h"
#include "rf_shutdown.h"
#include "rf_netbsd.h"
#include <sys/pool.h>
#include <sys/proc.h>
#define RF_MAX_FREE_MCPAIR 128
#define RF_MIN_FREE_MCPAIR 24
static void rf_ShutdownMCPair(void *);
static void
rf_ShutdownMCPair(void *ignored)
{
pool_destroy(&rf_pools.mcpair);
}
int
rf_ConfigureMCPair(RF_ShutdownList_t **listp)
{
rf_pool_init(&rf_pools.mcpair, sizeof(RF_MCPair_t),
"rf_mcpair_pl", RF_MIN_FREE_MCPAIR, RF_MAX_FREE_MCPAIR);
rf_ShutdownCreate(listp, rf_ShutdownMCPair, NULL);
return (0);
}
RF_MCPair_t *
rf_AllocMCPair(void)
{
RF_MCPair_t *t;
t = pool_get(&rf_pools.mcpair, PR_WAITOK);
rf_init_mutex2(t->mutex, IPL_VM);
rf_init_cond2(t->cond, "mcpair");
t->flag = 0;
return (t);
}
void
rf_FreeMCPair(RF_MCPair_t *t)
{
rf_destroy_cond2(t->cond);
rf_destroy_mutex2(t->mutex);
pool_put(&rf_pools.mcpair, t);
}
/* the callback function used to wake you up when you use an mcpair to
wait for something */
void
rf_MCPairWakeupFunc(RF_MCPair_t *mcpair)
{
RF_LOCK_MCPAIR(mcpair);
mcpair->flag = 1;
rf_broadcast_cond2(mcpair->cond);
RF_UNLOCK_MCPAIR(mcpair);
}