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/* $OpenBSD: rf_revent.c,v 1.10 2002/12/16 07:01:05 tdeval Exp $ */
/* $NetBSD: rf_revent.c,v 1.7 2000/05/30 02:04:29 oster Exp $ */
/*
* Copyright (c) 1995 Carnegie-Mellon University.
* All rights reserved.
*
* Author:
*
* 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.
*/
/*
* revent.c -- Reconstruction event handling code.
*/
#include <sys/errno.h>
#include "rf_raid.h"
#include "rf_revent.h"
#include "rf_etimer.h"
#include "rf_general.h"
#include "rf_freelist.h"
#include "rf_desc.h"
#include "rf_shutdown.h"
static RF_FreeList_t *rf_revent_freelist;
#define RF_MAX_FREE_REVENT 128
#define RF_REVENT_INC 8
#define RF_REVENT_INITIAL 8
#include <sys/proc.h>
#include <sys/kernel.h>
#define DO_WAIT(_rc) \
tsleep(&(_rc)->eventQueue, PRIBIO, "RAIDframe eventq", 0)
#define DO_SIGNAL(_rc) wakeup(&(_rc)->eventQueue)
void rf_ShutdownReconEvent(void *);
RF_ReconEvent_t *GetReconEventDesc(RF_RowCol_t, RF_RowCol_t, void *,
RF_Revent_t);
void
rf_ShutdownReconEvent(void *ignored)
{
RF_FREELIST_DESTROY(rf_revent_freelist, next, (RF_ReconEvent_t *));
}
int
rf_ConfigureReconEvent(RF_ShutdownList_t **listp)
{
int rc;
RF_FREELIST_CREATE(rf_revent_freelist, RF_MAX_FREE_REVENT,
RF_REVENT_INC, sizeof(RF_ReconEvent_t));
if (rf_revent_freelist == NULL)
return (ENOMEM);
rc = rf_ShutdownCreate(listp, rf_ShutdownReconEvent, NULL);
if (rc) {
RF_ERRORMSG3("Unable to add to shutdown list file %s line %d"
" rc=%d\n", __FILE__, __LINE__, rc);
rf_ShutdownReconEvent(NULL);
return (rc);
}
RF_FREELIST_PRIME(rf_revent_freelist, RF_REVENT_INITIAL, next,
(RF_ReconEvent_t *));
return (0);
}
/*
* Returns the next reconstruction event, blocking the calling thread
* until one becomes available. Will now return null if it is blocked
* or will return an event if it is not.
*/
RF_ReconEvent_t *
rf_GetNextReconEvent(RF_RaidReconDesc_t *reconDesc, RF_RowCol_t row,
void (*continueFunc) (void *), void *continueArg)
{
RF_Raid_t *raidPtr = reconDesc->raidPtr;
RF_ReconCtrl_t *rctrl = raidPtr->reconControl[row];
RF_ReconEvent_t *event;
RF_ASSERT(row >= 0 && row <= raidPtr->numRow);
RF_LOCK_MUTEX(rctrl->eq_mutex);
/* q NULL and count==0 must be equivalent conditions. */
RF_ASSERT((rctrl->eventQueue == NULL) == (rctrl->eq_count == 0));
rctrl->continueFunc = continueFunc;
rctrl->continueArg = continueArg;
/*
* mpsleep timeout value: secs = timo_val/hz. 'ticks' here is
* defined as cycle-counter ticks, not softclock ticks.
*/
#define MAX_RECON_EXEC_USECS (100 * 1000) /* 100 ms */
#define RECON_DELAY_MS 25
#define RECON_TIMO ((RECON_DELAY_MS * hz) / 1000)
/*
* We are not pre-emptible in the kernel, but we don't want to run
* forever. If we run w/o blocking for more than MAX_RECON_EXEC_USECS
* delay for RECON_DELAY_MS before continuing. This may murder us with
* context switches, so we may need to increase both the
* MAX...TICKS and the RECON_DELAY_MS.
*/
if (reconDesc->reconExecTimerRunning) {
int status;
RF_ETIMER_STOP(reconDesc->recon_exec_timer);
RF_ETIMER_EVAL(reconDesc->recon_exec_timer);
reconDesc->reconExecTicks +=
RF_ETIMER_VAL_US(reconDesc->recon_exec_timer);
if (reconDesc->reconExecTicks > reconDesc->maxReconExecTicks)
reconDesc->maxReconExecTicks =
reconDesc->reconExecTicks;
if (reconDesc->reconExecTicks >= MAX_RECON_EXEC_USECS) {
/* We've been running too long - sleep. */
#if RF_RECON_STATS > 0
reconDesc->numReconExecDelays++;
#endif /* RF_RECON_STATS > 0 */
status = tsleep(&reconDesc->reconExecTicks,
PRIBIO, "recon delay", RECON_TIMO);
RF_ASSERT(status == EWOULDBLOCK);
reconDesc->reconExecTicks = 0;
}
}
while (!rctrl->eventQueue) {
#if RF_RECON_STATS > 0
reconDesc->numReconEventWaits++;
#endif /* RF_RECON_STATS > 0 */
DO_WAIT(rctrl);
reconDesc->reconExecTicks = 0; /* We've just waited. */
}
RF_ETIMER_START(reconDesc->recon_exec_timer);
reconDesc->reconExecTimerRunning = 1;
event = rctrl->eventQueue;
rctrl->eventQueue = event->next;
event->next = NULL;
rctrl->eq_count--;
/* q NULL and count==0 must be equivalent conditions. */
RF_ASSERT((rctrl->eventQueue == NULL) == (rctrl->eq_count == 0));
RF_UNLOCK_MUTEX(rctrl->eq_mutex);
return (event);
}
/* Enqueues a reconstruction event on the indicated queue. */
void
rf_CauseReconEvent(RF_Raid_t *raidPtr, RF_RowCol_t row, RF_RowCol_t col,
void *arg, RF_Revent_t type)
{
RF_ReconCtrl_t *rctrl = raidPtr->reconControl[row];
RF_ReconEvent_t *event = GetReconEventDesc(row, col, arg, type);
if (type == RF_REVENT_BUFCLEAR) {
RF_ASSERT(col != rctrl->fcol);
}
RF_ASSERT(row >= 0 && row <= raidPtr->numRow && col >= 0 &&
col <= raidPtr->numCol);
RF_LOCK_MUTEX(rctrl->eq_mutex);
/* q NULL and count==0 must be equivalent conditions. */
RF_ASSERT((rctrl->eventQueue == NULL) == (rctrl->eq_count == 0));
event->next = rctrl->eventQueue;
rctrl->eventQueue = event;
rctrl->eq_count++;
RF_UNLOCK_MUTEX(rctrl->eq_mutex);
DO_SIGNAL(rctrl);
}
/* Allocates and initializes a recon event descriptor. */
RF_ReconEvent_t *
GetReconEventDesc(RF_RowCol_t row, RF_RowCol_t col, void *arg, RF_Revent_t type)
{
RF_ReconEvent_t *t;
RF_FREELIST_GET(rf_revent_freelist, t, next, (RF_ReconEvent_t *));
if (t == NULL)
return (NULL);
t->col = col;
t->arg = arg;
t->type = type;
return (t);
}
void
rf_FreeReconEventDesc(RF_ReconEvent_t *event)
{
RF_FREELIST_FREE(rf_revent_freelist, event, next);
}
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