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NetBSD/sys/dev/raidframe/rf_diskqueue.c

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/* $NetBSD: rf_diskqueue.c,v 1.4 1999/01/14 22:49:05 thorpej 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_diskqueue.c -- higher-level disk queue code
*
* the routines here are a generic wrapper around the actual queueing
* routines. The code here implements thread scheduling, synchronization,
* and locking ops (see below) on top of the lower-level queueing code.
*
* to support atomic RMW, we implement "locking operations". When a locking op
* is dispatched to the lower levels of the driver, the queue is locked, and no further
* I/Os are dispatched until the queue receives & completes a corresponding "unlocking
* operation". This code relies on the higher layers to guarantee that a locking
* op will always be eventually followed by an unlocking op. The model is that
* the higher layers are structured so locking and unlocking ops occur in pairs, i.e.
* an unlocking op cannot be generated until after a locking op reports completion.
* There is no good way to check to see that an unlocking op "corresponds" to the
* op that currently has the queue locked, so we make no such attempt. Since by
* definition there can be only one locking op outstanding on a disk, this should
* not be a problem.
*
* In the kernel, we allow multiple I/Os to be concurrently dispatched to the disk
* driver. In order to support locking ops in this environment, when we decide to
* do a locking op, we stop dispatching new I/Os and wait until all dispatched I/Os
* have completed before dispatching the locking op.
*
* Unfortunately, the code is different in the 3 different operating states
* (user level, kernel, simulator). In the kernel, I/O is non-blocking, and
* we have no disk threads to dispatch for us. Therefore, we have to dispatch
* new I/Os to the scsi driver at the time of enqueue, and also at the time
* of completion. At user level, I/O is blocking, and so only the disk threads
* may dispatch I/Os. Thus at user level, all we can do at enqueue time is
* enqueue and wake up the disk thread to do the dispatch.
*
***************************************************************************************/
/*
* :
*
* Log: rf_diskqueue.c,v
* Revision 1.50 1996/08/07 21:08:38 jimz
* b_proc -> kb_proc
*
* Revision 1.49 1996/07/05 20:36:14 jimz
* make rf_ConfigureDiskQueueSystem return 0
*
* Revision 1.48 1996/06/18 20:53:11 jimz
* fix up disk queueing (remove configure routine,
* add shutdown list arg to create routines)
*
* Revision 1.47 1996/06/14 14:16:36 jimz
* fix handling of bogus queue type
*
* Revision 1.46 1996/06/13 20:41:44 jimz
* add scan, cscan, random queueing
*
* Revision 1.45 1996/06/11 01:27:50 jimz
* Fixed bug where diskthread shutdown would crash or hang. This
* turned out to be two distinct bugs:
* (1) [crash] The thread shutdown code wasn't properly waiting for
* all the diskthreads to complete. This caused diskthreads that were
* exiting+cleaning up to unlock a destroyed mutex.
* (2) [hang] TerminateDiskQueues wasn't locking, and DiskIODequeue
* only checked for termination _after_ a wakeup if the queues were
* empty. This was a race where the termination wakeup could be lost
* by the dequeueing thread, and the system would hang waiting for the
* thread to exit, while the thread waited for an I/O or a signal to
* check the termination flag.
*
* Revision 1.44 1996/06/10 11:55:47 jimz
* Straightened out some per-array/not-per-array distinctions, fixed
* a couple bugs related to confusion. Added shutdown lists. Removed
* layout shutdown function (now subsumed by shutdown lists).
*
* Revision 1.43 1996/06/09 02:36:46 jimz
* lots of little crufty cleanup- fixup whitespace
* issues, comment #ifdefs, improve typing in some
* places (esp size-related)
*
* Revision 1.42 1996/06/07 22:26:27 jimz
* type-ify which_ru (RF_ReconUnitNum_t)
*
* Revision 1.41 1996/06/07 21:33:04 jimz
* begin using consistent types for sector numbers,
* stripe numbers, row+col numbers, recon unit numbers
*
* Revision 1.40 1996/06/06 17:28:04 jimz
* track sector number of last I/O dequeued
*
* Revision 1.39 1996/06/06 01:14:13 jimz
* fix crashing bug when tracerec is NULL (ie, from copyback)
* initialize req->queue
*
* Revision 1.38 1996/06/05 19:38:32 jimz
* fixed up disk queueing types config
* added sstf disk queueing
* fixed exit bug on diskthreads (ref-ing bad mem)
*
* Revision 1.37 1996/06/05 18:06:02 jimz
* Major code cleanup. The Great Renaming is now done.
* Better modularity. Better typing. Fixed a bunch of
* synchronization bugs. Made a lot of global stuff
* per-desc or per-array. Removed dead code.
*
* Revision 1.36 1996/05/30 23:22:16 jimz
* bugfixes of serialization, timing problems
* more cleanup
*
* Revision 1.35 1996/05/30 12:59:18 jimz
* make etimer happier, more portable
*
* Revision 1.34 1996/05/30 11:29:41 jimz
* Numerous bug fixes. Stripe lock release code disagreed with the taking code
* about when stripes should be locked (I made it consistent: no parity, no lock)
* There was a lot of extra serialization of I/Os which I've removed- a lot of
* it was to calculate values for the cache code, which is no longer with us.
* More types, function, macro cleanup. Added code to properly quiesce the array
* on shutdown. Made a lot of stuff array-specific which was (bogusly) general
* before. Fixed memory allocation, freeing bugs.
*
* Revision 1.33 1996/05/27 18:56:37 jimz
* more code cleanup
* better typing
* compiles in all 3 environments
*
* Revision 1.32 1996/05/24 22:17:04 jimz
* continue code + namespace cleanup
* typed a bunch of flags
*
* Revision 1.31 1996/05/24 01:59:45 jimz
* another checkpoint in code cleanup for release
* time to sync kernel tree
*
* Revision 1.30 1996/05/23 21:46:35 jimz
* checkpoint in code cleanup (release prep)
* lots of types, function names have been fixed
*
* Revision 1.29 1996/05/23 00:33:23 jimz
* code cleanup: move all debug decls to rf_options.c, all extern
* debug decls to rf_options.h, all debug vars preceded by rf_
*
* Revision 1.28 1996/05/20 16:14:29 jimz
* switch to rf_{mutex,cond}_{init,destroy}
*
* Revision 1.27 1996/05/18 19:51:34 jimz
* major code cleanup- fix syntax, make some types consistent,
* add prototypes, clean out dead code, et cetera
*
* Revision 1.26 1996/05/16 19:21:49 wvcii
* fixed typo in init_dqd
*
* Revision 1.25 1996/05/16 16:02:51 jimz
* switch to RF_FREELIST stuff for DiskQueueData
*
* Revision 1.24 1996/05/10 16:24:14 jimz
* new cvscan function names
*
* Revision 1.23 1996/05/01 16:27:54 jimz
* don't use ccmn bp management
*
* Revision 1.22 1995/12/12 18:10:06 jimz
* MIN -> RF_MIN, MAX -> RF_MAX, ASSERT -> RF_ASSERT
* fix 80-column brain damage in comments
*
* Revision 1.21 1995/12/01 15:59:59 root
* added copyright info
*
* Revision 1.20 1995/11/07 16:27:20 wvcii
* added Peek() function to diskqueuesw
* non-locking accesses are never blocked (assume clients enforce proper
* respect for lock acquisition)
*
* Revision 1.19 1995/10/05 18:56:52 jimz
* fix req handling in IOComplete
*
* Revision 1.18 1995/10/04 20:13:50 wvcii
* added asserts to monitor numOutstanding queueLength
*
* Revision 1.17 1995/10/04 07:43:52 wvcii
* queue->numOutstanding now valid for user & sim
* added queue->queueLength
* user tested & verified, sim untested
*
* Revision 1.16 1995/09/12 00:21:19 wvcii
* added support for tracing disk queue time
*
*/
#include "rf_types.h"
#include "rf_threadstuff.h"
#include "rf_threadid.h"
#include "rf_raid.h"
#include "rf_diskqueue.h"
#include "rf_alloclist.h"
#include "rf_acctrace.h"
#include "rf_etimer.h"
#include "rf_configure.h"
#include "rf_general.h"
#include "rf_freelist.h"
#include "rf_debugprint.h"
#include "rf_shutdown.h"
#include "rf_cvscan.h"
#include "rf_sstf.h"
#include "rf_fifo.h"
#ifdef SIMULATE
#include "rf_diskevent.h"
#endif /* SIMULATE */
#if !defined(__NetBSD__)
extern struct buf *ubc_bufget();
#endif
static int init_dqd(RF_DiskQueueData_t *);
static void clean_dqd(RF_DiskQueueData_t *);
static void rf_ShutdownDiskQueueSystem(void *);
/* From rf_kintf.c */
int rf_DispatchKernelIO(RF_DiskQueue_t *,RF_DiskQueueData_t *);
#define Dprintf1(s,a) if (rf_queueDebug) rf_debug_printf(s,(void *)((unsigned long)a),NULL,NULL,NULL,NULL,NULL,NULL,NULL)
#define Dprintf2(s,a,b) if (rf_queueDebug) rf_debug_printf(s,(void *)((unsigned long)a),(void *)((unsigned long)b),NULL,NULL,NULL,NULL,NULL,NULL)
#define Dprintf3(s,a,b,c) if (rf_queueDebug) rf_debug_printf(s,(void *)((unsigned long)a),(void *)((unsigned long)b),(void *)((unsigned long)c),NULL,NULL,NULL,NULL,NULL)
#define Dprintf4(s,a,b,c,d) if (rf_queueDebug) rf_debug_printf(s,(void *)((unsigned long)a),(void *)((unsigned long)b),(void *)((unsigned long)c),(void *)((unsigned long)d),NULL,NULL,NULL,NULL)
#define Dprintf5(s,a,b,c,d,e) if (rf_queueDebug) rf_debug_printf(s,(void *)((unsigned long)a),(void *)((unsigned long)b),(void *)((unsigned long)c),(void *)((unsigned long)d),(void *)((unsigned long)e),NULL,NULL,NULL)
#if !defined(KERNEL) && !defined(SIMULATE)
/* queue must be locked before invoking this */
#define SIGNAL_DISK_QUEUE(_q_,_wh_) \
{ \
if ( (_q_)->numWaiting > 0) { \
(_q_)->numWaiting--; \
RF_SIGNAL_COND( ((_q_)->cond) ); \
} \
}
/* queue must be locked before invoking this */
#define WAIT_DISK_QUEUE(_q_,_wh_) \
{ \
(_q_)->numWaiting++; \
RF_WAIT_COND( ((_q_)->cond), ((_q_)->mutex) ); \
}
#else /* !defined(KERNEL) && !defined(SIMULATE) */
#define SIGNAL_DISK_QUEUE(_q_,_wh_)
#define WAIT_DISK_QUEUE(_q_,_wh_)
#endif /* !defined(KERNEL) && !defined(SIMULATE) */
/*****************************************************************************************
*
* the disk queue switch defines all the functions used in the different queueing
* disciplines
* queue ID, init routine, enqueue routine, dequeue routine
*
****************************************************************************************/
static RF_DiskQueueSW_t diskqueuesw[] = {
{"fifo", /* FIFO */
rf_FifoCreate,
rf_FifoEnqueue,
rf_FifoDequeue,
rf_FifoPeek,
rf_FifoPromote},
{"cvscan", /* cvscan */
rf_CvscanCreate,
rf_CvscanEnqueue,
rf_CvscanDequeue,
rf_CvscanPeek,
rf_CvscanPromote },
{"sstf", /* shortest seek time first */
rf_SstfCreate,
rf_SstfEnqueue,
rf_SstfDequeue,
rf_SstfPeek,
rf_SstfPromote},
{"scan", /* SCAN (two-way elevator) */
rf_ScanCreate,
rf_SstfEnqueue,
rf_ScanDequeue,
rf_ScanPeek,
rf_SstfPromote},
{"cscan", /* CSCAN (one-way elevator) */
rf_CscanCreate,
rf_SstfEnqueue,
rf_CscanDequeue,
rf_CscanPeek,
rf_SstfPromote},
#if !defined(KERNEL) && RF_INCLUDE_QUEUE_RANDOM > 0
/* to make a point to Chris :-> */
{"random", /* random */
rf_FifoCreate,
rf_FifoEnqueue,
rf_RandomDequeue,
rf_RandomPeek,
rf_FifoPromote},
#endif /* !KERNEL && RF_INCLUDE_QUEUE_RANDOM > 0 */
};
#define NUM_DISK_QUEUE_TYPES (sizeof(diskqueuesw)/sizeof(RF_DiskQueueSW_t))
static RF_FreeList_t *rf_dqd_freelist;
#define RF_MAX_FREE_DQD 256
#define RF_DQD_INC 16
#define RF_DQD_INITIAL 64
#ifdef __NetBSD__
#ifdef _KERNEL
#include <sys/buf.h>
#endif
#endif
static int init_dqd(dqd)
RF_DiskQueueData_t *dqd;
{
#ifdef KERNEL
#ifdef __NetBSD__
/* XXX not sure if the following malloc is appropriate... probably not quite... */
dqd->bp = (struct buf *) malloc( sizeof(struct buf), M_RAIDFRAME, M_NOWAIT);
/* XXX */
/* printf("NEED TO IMPLEMENT THIS BETTER!\n"); */
#else
dqd->bp = ubc_bufget();
#endif
if (dqd->bp == NULL) {
return(ENOMEM);
}
#ifdef __NetBSD__
memset(dqd->bp,0,sizeof(struct buf)); /* if you don't do it, nobody else will.. */
#endif
#endif /* KERNEL */
return(0);
}
static void clean_dqd(dqd)
RF_DiskQueueData_t *dqd;
{
#ifdef KERNEL
#ifdef __NetBSD__
/* printf("NEED TO IMPLEMENT THIS BETTER(2)!\n"); */
/* XXX ? */
free( dqd->bp, M_RAIDFRAME );
#else
ubc_buffree(dqd->bp);
#endif
#endif /* KERNEL */
}
/* configures a single disk queue */
static int config_disk_queue(
RF_Raid_t *raidPtr,
RF_DiskQueue_t *diskqueue,
RF_RowCol_t r, /* row & col -- debug only. BZZT not any more... */
RF_RowCol_t c,
RF_DiskQueueSW_t *p,
RF_SectorCount_t sectPerDisk,
dev_t dev,
int maxOutstanding,
RF_ShutdownList_t **listp,
RF_AllocListElem_t *clList)
{
int rc;
diskqueue->row = r;
diskqueue->col = c;
diskqueue->qPtr = p;
diskqueue->qHdr = (p->Create)(sectPerDisk, clList, listp);
diskqueue->dev = dev;
diskqueue->numOutstanding = 0;
diskqueue->queueLength = 0;
diskqueue->maxOutstanding = maxOutstanding;
diskqueue->curPriority = RF_IO_NORMAL_PRIORITY;
diskqueue->nextLockingOp = NULL;
diskqueue->unlockingOp = NULL;
diskqueue->numWaiting=0;
diskqueue->flags = 0;
diskqueue->raidPtr = raidPtr;
#if defined(__NetBSD__) && defined(_KERNEL)
diskqueue->rf_cinfo = &raidPtr->raid_cinfo[r][c];
#endif
rc = rf_create_managed_mutex(listp, &diskqueue->mutex);
if (rc) {
RF_ERRORMSG3("Unable to init mutex file %s line %d rc=%d\n", __FILE__,
__LINE__, rc);
return(rc);
}
rc = rf_create_managed_cond(listp, &diskqueue->cond);
if (rc) {
RF_ERRORMSG3("Unable to init cond file %s line %d rc=%d\n", __FILE__,
__LINE__, rc);
return(rc);
}
return(0);
}
static void rf_ShutdownDiskQueueSystem(ignored)
void *ignored;
{
RF_FREELIST_DESTROY_CLEAN(rf_dqd_freelist,next,(RF_DiskQueueData_t *),clean_dqd);
}
int rf_ConfigureDiskQueueSystem(listp)
RF_ShutdownList_t **listp;
{
int rc;
RF_FREELIST_CREATE(rf_dqd_freelist, RF_MAX_FREE_DQD,
RF_DQD_INC, sizeof(RF_DiskQueueData_t));
if (rf_dqd_freelist == NULL)
return(ENOMEM);
rc = rf_ShutdownCreate(listp, rf_ShutdownDiskQueueSystem, NULL);
if (rc) {
RF_ERRORMSG3("Unable to add to shutdown list file %s line %d rc=%d\n",
__FILE__, __LINE__, rc);
rf_ShutdownDiskQueueSystem(NULL);
return(rc);
}
RF_FREELIST_PRIME_INIT(rf_dqd_freelist, RF_DQD_INITIAL,next,
(RF_DiskQueueData_t *),init_dqd);
return(0);
}
#ifndef KERNEL
/* this is called prior to shutdown to wakeup everyone waiting on a disk queue
* and tell them to exit
*/
void rf_TerminateDiskQueues(raidPtr)
RF_Raid_t *raidPtr;
{
RF_RowCol_t r, c;
raidPtr->terminate_disk_queues = 1;
for (r=0; r<raidPtr->numRow; r++) {
for (c=0; c<raidPtr->numCol + ((r==0) ? raidPtr->numSpare : 0); c++) {
RF_LOCK_QUEUE_MUTEX(&raidPtr->Queues[r][c], "TerminateDiskQueues");
RF_BROADCAST_COND(raidPtr->Queues[r][c].cond);
RF_UNLOCK_QUEUE_MUTEX(&raidPtr->Queues[r][c], "TerminateDiskQueues");
}
}
}
#endif /* !KERNEL */
int rf_ConfigureDiskQueues(
RF_ShutdownList_t **listp,
RF_Raid_t *raidPtr,
RF_Config_t *cfgPtr)
{
RF_DiskQueue_t **diskQueues, *spareQueues;
RF_DiskQueueSW_t *p;
RF_RowCol_t r, c;
int rc, i;
raidPtr->maxQueueDepth = cfgPtr->maxOutstandingDiskReqs;
for(p=NULL,i=0;i<NUM_DISK_QUEUE_TYPES;i++) {
if (!strcmp(diskqueuesw[i].queueType, cfgPtr->diskQueueType)) {
p = &diskqueuesw[i];
break;
}
}
if (p == NULL) {
RF_ERRORMSG2("Unknown queue type \"%s\". Using %s\n",cfgPtr->diskQueueType, diskqueuesw[0].queueType);
p = &diskqueuesw[0];
}
RF_CallocAndAdd(diskQueues, raidPtr->numRow, sizeof(RF_DiskQueue_t *), (RF_DiskQueue_t **), raidPtr->cleanupList);
if (diskQueues == NULL) {
return(ENOMEM);
}
raidPtr->Queues = diskQueues;
for (r=0; r<raidPtr->numRow; r++) {
RF_CallocAndAdd(diskQueues[r], raidPtr->numCol + ((r==0) ? raidPtr->numSpare : 0), sizeof(RF_DiskQueue_t), (RF_DiskQueue_t *), raidPtr->cleanupList);
if (diskQueues[r] == NULL)
return(ENOMEM);
for (c=0; c<raidPtr->numCol; c++) {
rc = config_disk_queue(raidPtr, &diskQueues[r][c], r, c, p,
raidPtr->sectorsPerDisk, raidPtr->Disks[r][c].dev,
cfgPtr->maxOutstandingDiskReqs, listp, raidPtr->cleanupList);
if (rc)
return(rc);
}
}
spareQueues = &raidPtr->Queues[0][raidPtr->numCol];
for (r=0; r<raidPtr->numSpare; r++) {
rc = config_disk_queue(raidPtr, &spareQueues[r],
0, raidPtr->numCol+r, p,
raidPtr->sectorsPerDisk,
raidPtr->Disks[0][raidPtr->numCol+r].dev,
cfgPtr->maxOutstandingDiskReqs, listp,
raidPtr->cleanupList);
if (rc)
return(rc);
}
return(0);
}
/* Enqueue a disk I/O
*
* Unfortunately, we have to do things differently in the different
* environments (simulator, user-level, kernel).
* At user level, all I/O is blocking, so we have 1 or more threads/disk
* and the thread that enqueues is different from the thread that dequeues.
* In the kernel, I/O is non-blocking and so we'd like to have multiple
* I/Os outstanding on the physical disks when possible.
*
* when any request arrives at a queue, we have two choices:
* dispatch it to the lower levels
* queue it up
*
* kernel rules for when to do what:
* locking request: queue empty => dispatch and lock queue,
* else queue it
* unlocking req : always dispatch it
* normal req : queue empty => dispatch it & set priority
* queue not full & priority is ok => dispatch it
* else queue it
*
* user-level rules:
* always enqueue. In the special case of an unlocking op, enqueue
* in a special way that will cause the unlocking op to be the next
* thing dequeued.
*
* simulator rules:
* Do the same as at user level, with the sleeps and wakeups suppressed.
*/
void rf_DiskIOEnqueue(queue, req, pri)
RF_DiskQueue_t *queue;
RF_DiskQueueData_t *req;
int pri;
{
int tid;
RF_ETIMER_START(req->qtime);
rf_get_threadid(tid);
RF_ASSERT(req->type == RF_IO_TYPE_NOP || req->numSector);
req->priority = pri;
if (rf_queueDebug && (req->numSector == 0)) {
printf("Warning: Enqueueing zero-sector access\n");
}
#ifdef KERNEL
/*
* kernel
*/
RF_LOCK_QUEUE_MUTEX( queue, "DiskIOEnqueue" );
/* locking request */
if (RF_LOCKING_REQ(req)) {
if (RF_QUEUE_EMPTY(queue)) {
Dprintf3("Dispatching pri %d locking op to r %d c %d (queue empty)\n",pri,queue->row, queue->col);
RF_LOCK_QUEUE(queue);
rf_DispatchKernelIO(queue, req);
} else {
queue->queueLength++; /* increment count of number of requests waiting in this queue */
Dprintf3("Enqueueing pri %d locking op to r %d c %d (queue not empty)\n",pri,queue->row, queue->col);
req->queue = (void *)queue;
(queue->qPtr->Enqueue)(queue->qHdr, req, pri);
}
}
/* unlocking request */
else if (RF_UNLOCKING_REQ(req)) { /* we'll do the actual unlock when this I/O completes */
Dprintf3("Dispatching pri %d unlocking op to r %d c %d\n",pri,queue->row, queue->col);
RF_ASSERT(RF_QUEUE_LOCKED(queue));
rf_DispatchKernelIO(queue, req);
}
/* normal request */
else if (RF_OK_TO_DISPATCH(queue, req)) {
Dprintf3("Dispatching pri %d regular op to r %d c %d (ok to dispatch)\n",pri,queue->row, queue->col);
rf_DispatchKernelIO(queue, req);
} else {
queue->queueLength++; /* increment count of number of requests waiting in this queue */
Dprintf3("Enqueueing pri %d regular op to r %d c %d (not ok to dispatch)\n",pri,queue->row, queue->col);
req->queue = (void *)queue;
(queue->qPtr->Enqueue)(queue->qHdr, req, pri);
}
RF_UNLOCK_QUEUE_MUTEX( queue, "DiskIOEnqueue" );
#else /* KERNEL */
/*
* user-level
*/
RF_LOCK_QUEUE_MUTEX( queue, "DiskIOEnqueue" );
queue->queueLength++; /* increment count of number of requests waiting in this queue */
/* unlocking request */
if (RF_UNLOCKING_REQ(req)) {
Dprintf4("[%d] enqueueing pri %d unlocking op & signalling r %d c %d\n", tid, pri, queue->row, queue->col);
RF_ASSERT(RF_QUEUE_LOCKED(queue) && queue->unlockingOp == NULL);
queue->unlockingOp = req;
}
/* locking and normal requests */
else {
req->queue = (void *)queue;
Dprintf5("[%d] enqueueing pri %d %s op & signalling r %d c %d\n", tid, pri,
(RF_LOCKING_REQ(req)) ? "locking" : "regular",queue->row,queue->col);
(queue->qPtr->Enqueue)(queue->qHdr, req, pri);
}
SIGNAL_DISK_QUEUE( queue, "DiskIOEnqueue");
RF_UNLOCK_QUEUE_MUTEX( queue, "DiskIOEnqueue" );
#endif /* KERNEL */
}
#if !defined(KERNEL) && !defined(SIMULATE)
/* user-level only: tell all threads to wake up & recheck the queue */
void rf_BroadcastOnQueue(queue)
RF_DiskQueue_t *queue;
{
int i;
if (queue->maxOutstanding > 1) for (i=0; i<queue->maxOutstanding; i++) {
SIGNAL_DISK_QUEUE(queue, "BroadcastOnQueue" );
}
}
#endif /* !KERNEL && !SIMULATE */
#ifndef KERNEL /* not used in kernel */
RF_DiskQueueData_t *rf_DiskIODequeue(queue)
RF_DiskQueue_t *queue;
{
RF_DiskQueueData_t *p, *headItem;
int tid;
rf_get_threadid(tid);
RF_LOCK_QUEUE_MUTEX( queue, "DiskIODequeue" );
for (p=NULL; !p; ) {
if (queue->unlockingOp) {
/* unlocking request */
RF_ASSERT(RF_QUEUE_LOCKED(queue));
p = queue->unlockingOp;
queue->unlockingOp = NULL;
Dprintf4("[%d] dequeueing pri %d unlocking op r %d c %d\n", tid, p->priority, queue->row,queue->col);
}
else {
headItem = (queue->qPtr->Peek)(queue->qHdr);
if (headItem) {
if (RF_LOCKING_REQ(headItem)) {
/* locking request */
if (!RF_QUEUE_LOCKED(queue)) {
/* queue isn't locked, so dequeue the request & lock the queue */
p = (queue->qPtr->Dequeue)( queue->qHdr );
if (p)
Dprintf4("[%d] dequeueing pri %d locking op r %d c %d\n", tid, p->priority, queue->row, queue->col);
else
Dprintf3("[%d] no dequeue -- raw queue empty r %d c %d\n", tid, queue->row, queue->col);
}
else {
/* queue already locked, no dequeue occurs */
Dprintf3("[%d] no dequeue -- queue is locked r %d c %d\n", tid, queue->row, queue->col);
p = NULL;
}
}
else {
/* normal request, always dequeue and assume caller already has lock (if needed) */
p = (queue->qPtr->Dequeue)( queue->qHdr );
if (p)
Dprintf4("[%d] dequeueing pri %d regular op r %d c %d\n", tid, p->priority, queue->row, queue->col);
else
Dprintf3("[%d] no dequeue -- raw queue empty r %d c %d\n", tid, queue->row, queue->col);
}
}
else {
Dprintf3("[%d] no dequeue -- raw queue empty r %d c %d\n", tid, queue->row, queue->col);
}
}
if (queue->raidPtr->terminate_disk_queues) {
p = NULL;
break;
}
#ifdef SIMULATE
break; /* in simulator, return NULL on empty queue instead of blocking */
#else /* SIMULATE */
if (!p) {
Dprintf3("[%d] nothing to dequeue: waiting r %d c %d\n", tid, queue->row, queue->col);
WAIT_DISK_QUEUE( queue, "DiskIODequeue" );
}
#endif /* SIMULATE */
}
if (p) {
queue->queueLength--; /* decrement count of number of requests waiting in this queue */
RF_ASSERT(queue->queueLength >= 0);
queue->numOutstanding++;
queue->last_deq_sector = p->sectorOffset;
/* record the amount of time this request spent in the disk queue */
RF_ETIMER_STOP(p->qtime);
RF_ETIMER_EVAL(p->qtime);
if (p->tracerec)
p->tracerec->diskqueue_us += RF_ETIMER_VAL_US(p->qtime);
}
if (p && RF_LOCKING_REQ(p)) {
RF_ASSERT(!RF_QUEUE_LOCKED(queue));
Dprintf3("[%d] locking queue r %d c %d\n",tid,queue->row,queue->col);
RF_LOCK_QUEUE(queue);
}
RF_UNLOCK_QUEUE_MUTEX( queue, "DiskIODequeue" );
return(p);
}
#else /* !KERNEL */
/* get the next set of I/Os started, kernel version only */
void rf_DiskIOComplete(queue, req, status)
RF_DiskQueue_t *queue;
RF_DiskQueueData_t *req;
int status;
{
int done=0;
RF_LOCK_QUEUE_MUTEX( queue, "DiskIOComplete" );
/* unlock the queue:
(1) after an unlocking req completes
(2) after a locking req fails
*/
if (RF_UNLOCKING_REQ(req) || (RF_LOCKING_REQ(req) && status)) {
Dprintf2("DiskIOComplete: unlocking queue at r %d c %d\n", queue->row, queue->col);
RF_ASSERT(RF_QUEUE_LOCKED(queue) && (queue->unlockingOp == NULL));
RF_UNLOCK_QUEUE(queue);
}
queue->numOutstanding--;
RF_ASSERT(queue->numOutstanding >= 0);
/* dispatch requests to the disk until we find one that we can't. */
/* no reason to continue once we've filled up the queue */
/* no reason to even start if the queue is locked */
while (!done && !RF_QUEUE_FULL(queue) && !RF_QUEUE_LOCKED(queue)) {
if (queue->nextLockingOp) {
req = queue->nextLockingOp; queue->nextLockingOp = NULL;
Dprintf3("DiskIOComplete: a pri %d locking req was pending at r %d c %d\n",req->priority,queue->row, queue->col);
} else {
req = (queue->qPtr->Dequeue)( queue->qHdr );
if (req != NULL) {
Dprintf3("DiskIOComplete: extracting pri %d req from queue at r %d c %d\n",req->priority,queue->row, queue->col);
} else {
Dprintf1("DiskIOComplete: no more requests to extract.\n","");
}
}
if (req) {
queue->queueLength--; /* decrement count of number of requests waiting in this queue */
RF_ASSERT(queue->queueLength >= 0);
}
if (!req) done=1;
else if (RF_LOCKING_REQ(req)) {
if (RF_QUEUE_EMPTY(queue)) { /* dispatch it */
Dprintf3("DiskIOComplete: dispatching pri %d locking req to r %d c %d (queue empty)\n",req->priority,queue->row, queue->col);
RF_LOCK_QUEUE(queue);
rf_DispatchKernelIO(queue, req);
done = 1;
} else { /* put it aside to wait for the queue to drain */
Dprintf3("DiskIOComplete: postponing pri %d locking req to r %d c %d\n",req->priority,queue->row, queue->col);
RF_ASSERT(queue->nextLockingOp == NULL);
queue->nextLockingOp = req;
done = 1;
}
} else if (RF_UNLOCKING_REQ(req)) { /* should not happen: unlocking ops should not get queued */
RF_ASSERT(RF_QUEUE_LOCKED(queue)); /* support it anyway for the future */
Dprintf3("DiskIOComplete: dispatching pri %d unl req to r %d c %d (SHOULD NOT SEE THIS)\n",req->priority,queue->row, queue->col);
rf_DispatchKernelIO(queue, req);
done = 1;
} else if (RF_OK_TO_DISPATCH(queue, req)) {
Dprintf3("DiskIOComplete: dispatching pri %d regular req to r %d c %d (ok to dispatch)\n",req->priority,queue->row, queue->col);
rf_DispatchKernelIO(queue, req);
} else { /* we can't dispatch it, so just re-enqueue it. */
/* potential trouble here if disk queues batch reqs */
Dprintf3("DiskIOComplete: re-enqueueing pri %d regular req to r %d c %d\n",req->priority,queue->row, queue->col);
queue->queueLength++;
(queue->qPtr->Enqueue)(queue->qHdr, req, req->priority);
done = 1;
}
}
RF_UNLOCK_QUEUE_MUTEX( queue, "DiskIOComplete" );
}
#endif /* !KERNEL */
/* promotes accesses tagged with the given parityStripeID from low priority
* to normal priority. This promotion is optional, meaning that a queue
* need not implement it. If there is no promotion routine associated with
* a queue, this routine does nothing and returns -1.
*/
int rf_DiskIOPromote(queue, parityStripeID, which_ru)
RF_DiskQueue_t *queue;
RF_StripeNum_t parityStripeID;
RF_ReconUnitNum_t which_ru;
{
int retval;
if (!queue->qPtr->Promote)
return(-1);
RF_LOCK_QUEUE_MUTEX( queue, "DiskIOPromote" );
retval = (queue->qPtr->Promote)( queue->qHdr, parityStripeID, which_ru );
RF_UNLOCK_QUEUE_MUTEX( queue, "DiskIOPromote" );
return(retval);
}
RF_DiskQueueData_t *rf_CreateDiskQueueData(
RF_IoType_t typ,
RF_SectorNum_t ssect,
RF_SectorCount_t nsect,
caddr_t buf,
RF_StripeNum_t parityStripeID,
RF_ReconUnitNum_t which_ru,
int (*wakeF)(void *,int),
void *arg,
RF_DiskQueueData_t *next,
RF_AccTraceEntry_t *tracerec,
void *raidPtr,
RF_DiskQueueDataFlags_t flags,
void *kb_proc)
{
RF_DiskQueueData_t *p;
RF_FREELIST_GET_INIT(rf_dqd_freelist,p,next,(RF_DiskQueueData_t *),init_dqd);
p->sectorOffset = ssect + rf_protectedSectors;
p->numSector = nsect;
p->type = typ;
p->buf = buf;
p->parityStripeID= parityStripeID;
p->which_ru = which_ru;
p->CompleteFunc = wakeF;
p->argument = arg;
p->next = next;
p->tracerec = tracerec;
p->priority = RF_IO_NORMAL_PRIORITY;
p->AuxFunc = NULL;
p->buf2 = NULL;
#ifdef SIMULATE
p->owner = rf_GetCurrentOwner();
#endif /* SIMULATE */
p->raidPtr = raidPtr;
p->flags = flags;
#ifdef KERNEL
p->b_proc = kb_proc;
#endif /* KERNEL */
return(p);
}
RF_DiskQueueData_t *rf_CreateDiskQueueDataFull(
RF_IoType_t typ,
RF_SectorNum_t ssect,
RF_SectorCount_t nsect,
caddr_t buf,
RF_StripeNum_t parityStripeID,
RF_ReconUnitNum_t which_ru,
int (*wakeF)(void *,int),
void *arg,
RF_DiskQueueData_t *next,
RF_AccTraceEntry_t *tracerec,
int priority,
int (*AuxFunc)(void *,...),
caddr_t buf2,
void *raidPtr,
RF_DiskQueueDataFlags_t flags,
void *kb_proc)
{
RF_DiskQueueData_t *p;
RF_FREELIST_GET_INIT(rf_dqd_freelist,p,next,(RF_DiskQueueData_t *),init_dqd);
p->sectorOffset = ssect + rf_protectedSectors;
p->numSector = nsect;
p->type = typ;
p->buf = buf;
p->parityStripeID= parityStripeID;
p->which_ru = which_ru;
p->CompleteFunc = wakeF;
p->argument = arg;
p->next = next;
p->tracerec = tracerec;
p->priority = priority;
p->AuxFunc = AuxFunc;
p->buf2 = buf2;
#ifdef SIMULATE
p->owner = rf_GetCurrentOwner();
#endif /* SIMULATE */
p->raidPtr = raidPtr;
p->flags = flags;
#ifdef KERNEL
p->b_proc = kb_proc;
#endif /* KERNEL */
return(p);
}
void rf_FreeDiskQueueData(p)
RF_DiskQueueData_t *p;
{
RF_FREELIST_FREE_CLEAN(rf_dqd_freelist,p,next,clean_dqd);
}
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