710948de69
world. This should be considered highly experimental. Approved-by: re
237 lines
6.5 KiB
C
237 lines
6.5 KiB
C
/* $FreeBSD$ */
|
|
/* $NetBSD: rf_fifo.c,v 1.5 2000/03/04 03:27:13 oster Exp $ */
|
|
/*
|
|
* Copyright (c) 1995 Carnegie-Mellon University.
|
|
* All rights reserved.
|
|
*
|
|
* Author: Mark Holland
|
|
*
|
|
* 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_fifo.c -- prioritized fifo queue code.
|
|
* There are only two priority levels: hi and lo.
|
|
*
|
|
* Aug 4, 1994, adapted from raidSim version (MCH)
|
|
*
|
|
***************************************************/
|
|
|
|
#include <dev/raidframe/rf_types.h>
|
|
#include <dev/raidframe/rf_alloclist.h>
|
|
#include <dev/raidframe/rf_stripelocks.h>
|
|
#include <dev/raidframe/rf_layout.h>
|
|
#include <dev/raidframe/rf_diskqueue.h>
|
|
#include <dev/raidframe/rf_fifo.h>
|
|
#include <dev/raidframe/rf_debugMem.h>
|
|
#include <dev/raidframe/rf_general.h>
|
|
#include <dev/raidframe/rf_options.h>
|
|
#include <dev/raidframe/rf_raid.h>
|
|
#include <dev/raidframe/rf_types.h>
|
|
|
|
/* just malloc a header, zero it (via calloc), and return it */
|
|
/*ARGSUSED*/
|
|
void *
|
|
rf_FifoCreate(sectPerDisk, clList, listp)
|
|
RF_SectorCount_t sectPerDisk;
|
|
RF_AllocListElem_t *clList;
|
|
RF_ShutdownList_t **listp;
|
|
{
|
|
RF_FifoHeader_t *q;
|
|
|
|
RF_CallocAndAdd(q, 1, sizeof(RF_FifoHeader_t), (RF_FifoHeader_t *), clList);
|
|
q->hq_count = q->lq_count = 0;
|
|
return ((void *) q);
|
|
}
|
|
|
|
void
|
|
rf_FifoEnqueue(q_in, elem, priority)
|
|
void *q_in;
|
|
RF_DiskQueueData_t *elem;
|
|
int priority;
|
|
{
|
|
RF_FifoHeader_t *q = (RF_FifoHeader_t *) q_in;
|
|
|
|
RF_ASSERT(priority == RF_IO_NORMAL_PRIORITY || priority == RF_IO_LOW_PRIORITY);
|
|
|
|
elem->next = NULL;
|
|
if (priority == RF_IO_NORMAL_PRIORITY) {
|
|
if (!q->hq_tail) {
|
|
RF_ASSERT(q->hq_count == 0 && q->hq_head == NULL);
|
|
q->hq_head = q->hq_tail = elem;
|
|
} else {
|
|
RF_ASSERT(q->hq_count != 0 && q->hq_head != NULL);
|
|
q->hq_tail->next = elem;
|
|
q->hq_tail = elem;
|
|
}
|
|
q->hq_count++;
|
|
} else {
|
|
RF_ASSERT(elem->next == NULL);
|
|
if (rf_fifoDebug) {
|
|
printf("raid%d: fifo: ENQ lopri\n",
|
|
elem->raidPtr->raidid);
|
|
}
|
|
if (!q->lq_tail) {
|
|
RF_ASSERT(q->lq_count == 0 && q->lq_head == NULL);
|
|
q->lq_head = q->lq_tail = elem;
|
|
} else {
|
|
RF_ASSERT(q->lq_count != 0 && q->lq_head != NULL);
|
|
q->lq_tail->next = elem;
|
|
q->lq_tail = elem;
|
|
}
|
|
q->lq_count++;
|
|
}
|
|
if ((q->hq_count + q->lq_count) != elem->queue->queueLength) {
|
|
printf("Queue lengths differ!: %d %d %d\n",
|
|
q->hq_count, q->lq_count, (int) elem->queue->queueLength);
|
|
printf("%d %d %d %d\n",
|
|
(int) elem->queue->numOutstanding,
|
|
(int) elem->queue->maxOutstanding,
|
|
(int) elem->queue->row,
|
|
(int) elem->queue->col);
|
|
}
|
|
RF_ASSERT((q->hq_count + q->lq_count) == elem->queue->queueLength);
|
|
}
|
|
|
|
RF_DiskQueueData_t *
|
|
rf_FifoDequeue(q_in)
|
|
void *q_in;
|
|
{
|
|
RF_FifoHeader_t *q = (RF_FifoHeader_t *) q_in;
|
|
RF_DiskQueueData_t *nd;
|
|
|
|
RF_ASSERT(q);
|
|
if (q->hq_head) {
|
|
RF_ASSERT(q->hq_count != 0 && q->hq_tail != NULL);
|
|
nd = q->hq_head;
|
|
q->hq_head = q->hq_head->next;
|
|
if (!q->hq_head)
|
|
q->hq_tail = NULL;
|
|
nd->next = NULL;
|
|
q->hq_count--;
|
|
} else
|
|
if (q->lq_head) {
|
|
RF_ASSERT(q->lq_count != 0 && q->lq_tail != NULL);
|
|
nd = q->lq_head;
|
|
q->lq_head = q->lq_head->next;
|
|
if (!q->lq_head)
|
|
q->lq_tail = NULL;
|
|
nd->next = NULL;
|
|
q->lq_count--;
|
|
if (rf_fifoDebug) {
|
|
printf("raid%d: fifo: DEQ lopri %lx\n",
|
|
nd->raidPtr->raidid, (long) nd);
|
|
}
|
|
} else {
|
|
RF_ASSERT(q->hq_count == 0 && q->lq_count == 0 && q->hq_tail == NULL && q->lq_tail == NULL);
|
|
nd = NULL;
|
|
}
|
|
return (nd);
|
|
}
|
|
|
|
/* Return ptr to item at head of queue. Used to examine request
|
|
* info without actually dequeueing the request.
|
|
*/
|
|
RF_DiskQueueData_t *
|
|
rf_FifoPeek(void *q_in)
|
|
{
|
|
RF_DiskQueueData_t *headElement = NULL;
|
|
RF_FifoHeader_t *q = (RF_FifoHeader_t *) q_in;
|
|
|
|
RF_ASSERT(q);
|
|
if (q->hq_head)
|
|
headElement = q->hq_head;
|
|
else
|
|
if (q->lq_head)
|
|
headElement = q->lq_head;
|
|
return (headElement);
|
|
}
|
|
/* We sometimes need to promote a low priority access to a regular priority access.
|
|
* Currently, this is only used when the user wants to write a stripe which is currently
|
|
* under reconstruction.
|
|
* This routine will promote all accesses tagged with the indicated parityStripeID from
|
|
* the low priority queue to the end of the normal priority queue.
|
|
* We assume the queue is locked upon entry.
|
|
*/
|
|
int
|
|
rf_FifoPromote(q_in, parityStripeID, which_ru)
|
|
void *q_in;
|
|
RF_StripeNum_t parityStripeID;
|
|
RF_ReconUnitNum_t which_ru;
|
|
{
|
|
RF_FifoHeader_t *q = (RF_FifoHeader_t *) q_in;
|
|
RF_DiskQueueData_t *lp = q->lq_head, *pt = NULL; /* lp = lo-pri queue
|
|
* pointer, pt = trailer */
|
|
int retval = 0;
|
|
|
|
while (lp) {
|
|
|
|
/* search for the indicated parity stripe in the low-pri queue */
|
|
if (lp->parityStripeID == parityStripeID && lp->which_ru == which_ru) {
|
|
/* printf("FifoPromote: promoting access for psid
|
|
* %ld\n",parityStripeID); */
|
|
if (pt)
|
|
pt->next = lp->next; /* delete an entry other
|
|
* than the first */
|
|
else
|
|
q->lq_head = lp->next; /* delete the head entry */
|
|
|
|
if (!q->lq_head)
|
|
q->lq_tail = NULL; /* we deleted the only
|
|
* entry */
|
|
else
|
|
if (lp == q->lq_tail)
|
|
q->lq_tail = pt; /* we deleted the tail
|
|
* entry */
|
|
|
|
lp->next = NULL;
|
|
q->lq_count--;
|
|
|
|
if (q->hq_tail) {
|
|
q->hq_tail->next = lp;
|
|
q->hq_tail = lp;
|
|
}
|
|
/* append to hi-priority queue */
|
|
else {
|
|
q->hq_head = q->hq_tail = lp;
|
|
}
|
|
q->hq_count++;
|
|
|
|
/* UpdateShortestSeekFinishTimeForced(lp->requestPtr,
|
|
* lp->diskState); *//* deal with this later, if ever */
|
|
|
|
lp = (pt) ? pt->next : q->lq_head; /* reset low-pri pointer
|
|
* and continue */
|
|
retval++;
|
|
|
|
} else {
|
|
pt = lp;
|
|
lp = lp->next;
|
|
}
|
|
}
|
|
|
|
/* sanity check. delete this if you ever put more than one entry in
|
|
* the low-pri queue */
|
|
RF_ASSERT(retval == 0 || retval == 1);
|
|
return (retval);
|
|
}
|