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rf_states.c revision 1.38.4.2
      1  1.38.4.2      yamt /*	$NetBSD: rf_states.c,v 1.38.4.2 2007/09/03 14:38:23 yamt Exp $	*/
      2       1.1     oster /*
      3       1.1     oster  * Copyright (c) 1995 Carnegie-Mellon University.
      4       1.1     oster  * All rights reserved.
      5       1.1     oster  *
      6       1.1     oster  * Author: Mark Holland, William V. Courtright II, Robby Findler
      7       1.1     oster  *
      8       1.1     oster  * Permission to use, copy, modify and distribute this software and
      9       1.1     oster  * its documentation is hereby granted, provided that both the copyright
     10       1.1     oster  * notice and this permission notice appear in all copies of the
     11       1.1     oster  * software, derivative works or modified versions, and any portions
     12       1.1     oster  * thereof, and that both notices appear in supporting documentation.
     13       1.1     oster  *
     14       1.1     oster  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
     15       1.1     oster  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
     16       1.1     oster  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
     17       1.1     oster  *
     18       1.1     oster  * Carnegie Mellon requests users of this software to return to
     19       1.1     oster  *
     20       1.1     oster  *  Software Distribution Coordinator  or  Software.Distribution (at) CS.CMU.EDU
     21       1.1     oster  *  School of Computer Science
     22       1.1     oster  *  Carnegie Mellon University
     23       1.1     oster  *  Pittsburgh PA 15213-3890
     24       1.1     oster  *
     25       1.1     oster  * any improvements or extensions that they make and grant Carnegie the
     26       1.1     oster  * rights to redistribute these changes.
     27       1.1     oster  */
     28      1.16     lukem 
     29      1.16     lukem #include <sys/cdefs.h>
     30  1.38.4.2      yamt __KERNEL_RCSID(0, "$NetBSD: rf_states.c,v 1.38.4.2 2007/09/03 14:38:23 yamt Exp $");
     31       1.1     oster 
     32       1.1     oster #include <sys/errno.h>
     33       1.1     oster 
     34       1.1     oster #include "rf_archs.h"
     35       1.1     oster #include "rf_threadstuff.h"
     36       1.1     oster #include "rf_raid.h"
     37       1.1     oster #include "rf_dag.h"
     38       1.1     oster #include "rf_desc.h"
     39       1.1     oster #include "rf_aselect.h"
     40       1.1     oster #include "rf_general.h"
     41       1.1     oster #include "rf_states.h"
     42       1.1     oster #include "rf_dagutils.h"
     43       1.1     oster #include "rf_driver.h"
     44       1.1     oster #include "rf_engine.h"
     45       1.1     oster #include "rf_map.h"
     46       1.1     oster #include "rf_etimer.h"
     47      1.10     oster #include "rf_kintf.h"
     48       1.1     oster 
     49      1.19     oster #ifndef RF_DEBUG_STATES
     50      1.19     oster #define RF_DEBUG_STATES 0
     51      1.19     oster #endif
     52      1.19     oster 
     53       1.1     oster /* prototypes for some of the available states.
     54       1.1     oster 
     55       1.1     oster    States must:
     56       1.1     oster 
     57       1.1     oster      - not block.
     58       1.1     oster 
     59       1.1     oster      - either schedule rf_ContinueRaidAccess as a callback and return
     60       1.1     oster        RF_TRUE, or complete all of their work and return RF_FALSE.
     61       1.1     oster 
     62       1.1     oster      - increment desc->state when they have finished their work.
     63       1.1     oster */
     64       1.1     oster 
     65      1.19     oster #if RF_DEBUG_STATES
     66       1.6     oster static char *
     67       1.6     oster StateName(RF_AccessState_t state)
     68       1.1     oster {
     69       1.6     oster 	switch (state) {
     70       1.6     oster 		case rf_QuiesceState:return "QuiesceState";
     71       1.6     oster 	case rf_MapState:
     72       1.6     oster 		return "MapState";
     73       1.6     oster 	case rf_LockState:
     74       1.6     oster 		return "LockState";
     75       1.6     oster 	case rf_CreateDAGState:
     76       1.6     oster 		return "CreateDAGState";
     77       1.6     oster 	case rf_ExecuteDAGState:
     78       1.6     oster 		return "ExecuteDAGState";
     79       1.6     oster 	case rf_ProcessDAGState:
     80       1.6     oster 		return "ProcessDAGState";
     81       1.6     oster 	case rf_CleanupState:
     82       1.6     oster 		return "CleanupState";
     83       1.6     oster 	case rf_LastState:
     84       1.6     oster 		return "LastState";
     85       1.6     oster 	case rf_IncrAccessesCountState:
     86       1.6     oster 		return "IncrAccessesCountState";
     87       1.6     oster 	case rf_DecrAccessesCountState:
     88       1.6     oster 		return "DecrAccessesCountState";
     89       1.6     oster 	default:
     90       1.6     oster 		return "!!! UnnamedState !!!";
     91       1.6     oster 	}
     92       1.6     oster }
     93      1.19     oster #endif
     94       1.6     oster 
     95      1.38     perry void
     96      1.22     oster rf_ContinueRaidAccess(RF_RaidAccessDesc_t *desc)
     97       1.6     oster {
     98       1.6     oster 	int     suspended = RF_FALSE;
     99       1.6     oster 	int     current_state_index = desc->state;
    100       1.6     oster 	RF_AccessState_t current_state = desc->states[current_state_index];
    101      1.19     oster #if RF_DEBUG_STATES
    102      1.12     oster 	int     unit = desc->raidPtr->raidid;
    103      1.19     oster #endif
    104       1.6     oster 
    105       1.6     oster 	do {
    106       1.6     oster 
    107       1.6     oster 		current_state_index = desc->state;
    108       1.6     oster 		current_state = desc->states[current_state_index];
    109       1.6     oster 
    110       1.6     oster 		switch (current_state) {
    111       1.6     oster 
    112       1.6     oster 		case rf_QuiesceState:
    113       1.6     oster 			suspended = rf_State_Quiesce(desc);
    114       1.6     oster 			break;
    115       1.6     oster 		case rf_IncrAccessesCountState:
    116       1.6     oster 			suspended = rf_State_IncrAccessCount(desc);
    117       1.6     oster 			break;
    118       1.6     oster 		case rf_MapState:
    119       1.6     oster 			suspended = rf_State_Map(desc);
    120       1.6     oster 			break;
    121       1.6     oster 		case rf_LockState:
    122       1.6     oster 			suspended = rf_State_Lock(desc);
    123       1.6     oster 			break;
    124       1.6     oster 		case rf_CreateDAGState:
    125       1.6     oster 			suspended = rf_State_CreateDAG(desc);
    126       1.6     oster 			break;
    127       1.6     oster 		case rf_ExecuteDAGState:
    128       1.6     oster 			suspended = rf_State_ExecuteDAG(desc);
    129       1.6     oster 			break;
    130       1.6     oster 		case rf_ProcessDAGState:
    131       1.6     oster 			suspended = rf_State_ProcessDAG(desc);
    132       1.6     oster 			break;
    133       1.6     oster 		case rf_CleanupState:
    134       1.6     oster 			suspended = rf_State_Cleanup(desc);
    135       1.6     oster 			break;
    136       1.6     oster 		case rf_DecrAccessesCountState:
    137       1.6     oster 			suspended = rf_State_DecrAccessCount(desc);
    138       1.6     oster 			break;
    139       1.6     oster 		case rf_LastState:
    140       1.6     oster 			suspended = rf_State_LastState(desc);
    141       1.6     oster 			break;
    142       1.6     oster 		}
    143       1.6     oster 
    144      1.23     oster 		/* after this point, we cannot dereference desc since
    145      1.23     oster 		 * desc may have been freed. desc is only freed in
    146      1.23     oster 		 * LastState, so if we renter this function or loop
    147      1.23     oster 		 * back up, desc should be valid. */
    148       1.6     oster 
    149      1.19     oster #if RF_DEBUG_STATES
    150       1.6     oster 		if (rf_printStatesDebug) {
    151      1.12     oster 			printf("raid%d: State: %-24s StateIndex: %3i desc: 0x%ld %s\n",
    152      1.38     perry 			       unit, StateName(current_state),
    153      1.12     oster 			       current_state_index, (long) desc,
    154      1.12     oster 			       suspended ? "callback scheduled" : "looping");
    155       1.6     oster 		}
    156      1.19     oster #endif
    157       1.6     oster 	} while (!suspended && current_state != rf_LastState);
    158       1.6     oster 
    159       1.6     oster 	return;
    160       1.6     oster }
    161       1.6     oster 
    162       1.6     oster 
    163      1.38     perry void
    164      1.22     oster rf_ContinueDagAccess(RF_DagList_t *dagList)
    165       1.6     oster {
    166      1.27     oster #if RF_ACC_TRACE > 0
    167       1.6     oster 	RF_AccTraceEntry_t *tracerec = &(dagList->desc->tracerec);
    168      1.28     oster 	RF_Etimer_t timer;
    169      1.27     oster #endif
    170       1.6     oster 	RF_RaidAccessDesc_t *desc;
    171       1.6     oster 	RF_DagHeader_t *dag_h;
    172       1.6     oster 	int     i;
    173       1.6     oster 
    174       1.6     oster 	desc = dagList->desc;
    175       1.6     oster 
    176      1.27     oster #if RF_ACC_TRACE > 0
    177       1.6     oster 	timer = tracerec->timer;
    178       1.6     oster 	RF_ETIMER_STOP(timer);
    179       1.6     oster 	RF_ETIMER_EVAL(timer);
    180       1.6     oster 	tracerec->specific.user.exec_us = RF_ETIMER_VAL_US(timer);
    181       1.6     oster 	RF_ETIMER_START(tracerec->timer);
    182      1.27     oster #endif
    183       1.6     oster 
    184       1.6     oster 	/* skip to dag which just finished */
    185       1.6     oster 	dag_h = dagList->dags;
    186       1.6     oster 	for (i = 0; i < dagList->numDagsDone; i++) {
    187       1.6     oster 		dag_h = dag_h->next;
    188       1.6     oster 	}
    189       1.6     oster 
    190       1.6     oster 	/* check to see if retry is required */
    191       1.6     oster 	if (dag_h->status == rf_rollBackward) {
    192      1.23     oster 		/* when a dag fails, mark desc status as bad and allow
    193      1.23     oster 		 * all other dags in the desc to execute to
    194      1.23     oster 		 * completion.  then, free all dags and start over */
    195       1.6     oster 		desc->status = 1;	/* bad status */
    196      1.25     oster #if 0
    197      1.25     oster 		printf("raid%d: DAG failure: %c addr 0x%lx "
    198      1.25     oster 		       "(%ld) nblk 0x%x (%d) buf 0x%lx state %d\n",
    199      1.38     perry 		       desc->raidPtr->raidid, desc->type,
    200      1.23     oster 		       (long) desc->raidAddress,
    201      1.23     oster 		       (long) desc->raidAddress, (int) desc->numBlocks,
    202      1.38     perry 		       (int) desc->numBlocks,
    203      1.25     oster 		       (unsigned long) (desc->bufPtr), desc->state);
    204      1.25     oster #endif
    205       1.6     oster 	}
    206       1.6     oster 	dagList->numDagsDone++;
    207       1.6     oster 	rf_ContinueRaidAccess(desc);
    208       1.6     oster }
    209       1.6     oster 
    210      1.38     perry int
    211      1.22     oster rf_State_LastState(RF_RaidAccessDesc_t *desc)
    212       1.1     oster {
    213       1.6     oster 	void    (*callbackFunc) (RF_CBParam_t) = desc->callbackFunc;
    214       1.6     oster 	RF_CBParam_t callbackArg;
    215       1.2  drochner 
    216       1.6     oster 	callbackArg.p = desc->callbackArg;
    217      1.38     perry 
    218       1.8     oster 	/*
    219       1.8     oster 	 * If this is not an async request, wake up the caller
    220       1.8     oster 	 */
    221       1.8     oster 	if (desc->async_flag == 0)
    222       1.8     oster 		wakeup(desc->bp);
    223      1.15     oster 
    224      1.15     oster 	/*
    225      1.15     oster 	 * That's all the IO for this one... unbusy the 'disk'.
    226      1.15     oster 	 */
    227      1.15     oster 
    228      1.15     oster 	rf_disk_unbusy(desc);
    229      1.15     oster 
    230      1.38     perry 	/*
    231       1.8     oster 	 * Wakeup any requests waiting to go.
    232       1.8     oster 	 */
    233      1.38     perry 
    234       1.8     oster 	RF_LOCK_MUTEX(((RF_Raid_t *) desc->raidPtr)->mutex);
    235       1.8     oster 	((RF_Raid_t *) desc->raidPtr)->openings++;
    236       1.8     oster 	RF_UNLOCK_MUTEX(((RF_Raid_t *) desc->raidPtr)->mutex);
    237      1.10     oster 
    238  1.38.4.1      yamt 	wakeup(&(desc->raidPtr->iodone));
    239      1.38     perry 
    240       1.8     oster 	/* printf("Calling biodone on 0x%x\n",desc->bp); */
    241       1.8     oster 	biodone(desc->bp);	/* access came through ioctl */
    242       1.3  explorer 
    243       1.6     oster 	if (callbackFunc)
    244       1.6     oster 		callbackFunc(callbackArg);
    245       1.6     oster 	rf_FreeRaidAccDesc(desc);
    246       1.6     oster 
    247       1.6     oster 	return RF_FALSE;
    248       1.6     oster }
    249       1.6     oster 
    250      1.38     perry int
    251      1.22     oster rf_State_IncrAccessCount(RF_RaidAccessDesc_t *desc)
    252       1.6     oster {
    253       1.6     oster 	RF_Raid_t *raidPtr;
    254       1.6     oster 
    255       1.6     oster 	raidPtr = desc->raidPtr;
    256       1.6     oster 	/* Bummer. We have to do this to be 100% safe w.r.t. the increment
    257       1.6     oster 	 * below */
    258       1.6     oster 	RF_LOCK_MUTEX(raidPtr->access_suspend_mutex);
    259       1.6     oster 	raidPtr->accs_in_flight++;	/* used to detect quiescence */
    260       1.6     oster 	RF_UNLOCK_MUTEX(raidPtr->access_suspend_mutex);
    261       1.6     oster 
    262       1.6     oster 	desc->state++;
    263       1.6     oster 	return RF_FALSE;
    264       1.6     oster }
    265       1.6     oster 
    266      1.38     perry int
    267      1.22     oster rf_State_DecrAccessCount(RF_RaidAccessDesc_t *desc)
    268       1.6     oster {
    269       1.6     oster 	RF_Raid_t *raidPtr;
    270       1.6     oster 
    271       1.6     oster 	raidPtr = desc->raidPtr;
    272       1.6     oster 
    273       1.6     oster 	RF_LOCK_MUTEX(raidPtr->access_suspend_mutex);
    274       1.6     oster 	raidPtr->accs_in_flight--;
    275       1.6     oster 	if (raidPtr->accesses_suspended && raidPtr->accs_in_flight == 0) {
    276      1.20     oster 		rf_SignalQuiescenceLock(raidPtr);
    277       1.6     oster 	}
    278       1.6     oster 	RF_UNLOCK_MUTEX(raidPtr->access_suspend_mutex);
    279       1.6     oster 
    280       1.6     oster 	desc->state++;
    281       1.6     oster 	return RF_FALSE;
    282       1.6     oster }
    283       1.6     oster 
    284      1.38     perry int
    285      1.22     oster rf_State_Quiesce(RF_RaidAccessDesc_t *desc)
    286       1.6     oster {
    287      1.27     oster #if RF_ACC_TRACE > 0
    288       1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    289       1.6     oster 	RF_Etimer_t timer;
    290      1.27     oster #endif
    291      1.31     oster 	RF_CallbackDesc_t *cb;
    292      1.31     oster 	RF_Raid_t *raidPtr;
    293       1.6     oster 	int     suspended = RF_FALSE;
    294      1.31     oster 	int need_cb, used_cb;
    295       1.6     oster 
    296       1.6     oster 	raidPtr = desc->raidPtr;
    297       1.6     oster 
    298      1.27     oster #if RF_ACC_TRACE > 0
    299       1.6     oster 	RF_ETIMER_START(timer);
    300       1.6     oster 	RF_ETIMER_START(desc->timer);
    301      1.27     oster #endif
    302       1.6     oster 
    303      1.31     oster 	need_cb = 0;
    304      1.31     oster 	used_cb = 0;
    305      1.31     oster 	cb = NULL;
    306      1.31     oster 
    307       1.6     oster 	RF_LOCK_MUTEX(raidPtr->access_suspend_mutex);
    308      1.31     oster 	/* Do an initial check to see if we might need a callback structure */
    309       1.6     oster 	if (raidPtr->accesses_suspended) {
    310      1.31     oster 		need_cb = 1;
    311      1.31     oster 	}
    312      1.31     oster 	RF_UNLOCK_MUTEX(raidPtr->access_suspend_mutex);
    313      1.31     oster 
    314      1.31     oster 	if (need_cb) {
    315      1.31     oster 		/* create a callback if we might need it...
    316      1.31     oster 		   and we likely do. */
    317       1.6     oster 		cb = rf_AllocCallbackDesc();
    318      1.31     oster 	}
    319      1.23     oster 
    320      1.31     oster 	RF_LOCK_MUTEX(raidPtr->access_suspend_mutex);
    321      1.31     oster 	if (raidPtr->accesses_suspended) {
    322       1.6     oster 		cb->callbackFunc = (void (*) (RF_CBParam_t)) rf_ContinueRaidAccess;
    323       1.6     oster 		cb->callbackArg.p = (void *) desc;
    324       1.6     oster 		cb->next = raidPtr->quiesce_wait_list;
    325       1.6     oster 		raidPtr->quiesce_wait_list = cb;
    326       1.6     oster 		suspended = RF_TRUE;
    327      1.31     oster 		used_cb = 1;
    328       1.6     oster 	}
    329       1.6     oster 	RF_UNLOCK_MUTEX(raidPtr->access_suspend_mutex);
    330       1.6     oster 
    331      1.31     oster 	if ((need_cb == 1) && (used_cb == 0)) {
    332      1.31     oster 		rf_FreeCallbackDesc(cb);
    333      1.31     oster 	}
    334      1.31     oster 
    335      1.27     oster #if RF_ACC_TRACE > 0
    336       1.6     oster 	RF_ETIMER_STOP(timer);
    337       1.6     oster 	RF_ETIMER_EVAL(timer);
    338       1.6     oster 	tracerec->specific.user.suspend_ovhd_us += RF_ETIMER_VAL_US(timer);
    339      1.27     oster #endif
    340       1.6     oster 
    341      1.18     oster #if RF_DEBUG_QUIESCE
    342       1.6     oster 	if (suspended && rf_quiesceDebug)
    343       1.6     oster 		printf("Stalling access due to quiescence lock\n");
    344      1.18     oster #endif
    345       1.6     oster 	desc->state++;
    346       1.6     oster 	return suspended;
    347       1.6     oster }
    348       1.6     oster 
    349      1.38     perry int
    350      1.22     oster rf_State_Map(RF_RaidAccessDesc_t *desc)
    351       1.6     oster {
    352       1.6     oster 	RF_Raid_t *raidPtr = desc->raidPtr;
    353      1.27     oster #if RF_ACC_TRACE > 0
    354       1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    355       1.6     oster 	RF_Etimer_t timer;
    356       1.6     oster 
    357       1.6     oster 	RF_ETIMER_START(timer);
    358      1.27     oster #endif
    359       1.6     oster 
    360       1.6     oster 	if (!(desc->asmap = rf_MapAccess(raidPtr, desc->raidAddress, desc->numBlocks,
    361       1.6     oster 		    desc->bufPtr, RF_DONT_REMAP)))
    362       1.6     oster 		RF_PANIC();
    363       1.6     oster 
    364      1.27     oster #if RF_ACC_TRACE > 0
    365       1.6     oster 	RF_ETIMER_STOP(timer);
    366       1.6     oster 	RF_ETIMER_EVAL(timer);
    367       1.6     oster 	tracerec->specific.user.map_us = RF_ETIMER_VAL_US(timer);
    368      1.27     oster #endif
    369       1.6     oster 
    370       1.6     oster 	desc->state++;
    371       1.6     oster 	return RF_FALSE;
    372       1.6     oster }
    373       1.6     oster 
    374      1.38     perry int
    375      1.22     oster rf_State_Lock(RF_RaidAccessDesc_t *desc)
    376       1.6     oster {
    377      1.27     oster #if RF_ACC_TRACE > 0
    378       1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    379      1.28     oster 	RF_Etimer_t timer;
    380      1.27     oster #endif
    381       1.6     oster 	RF_Raid_t *raidPtr = desc->raidPtr;
    382       1.6     oster 	RF_AccessStripeMapHeader_t *asmh = desc->asmap;
    383       1.6     oster 	RF_AccessStripeMap_t *asm_p;
    384      1.32     oster 	RF_StripeNum_t lastStripeID = -1;
    385       1.6     oster 	int     suspended = RF_FALSE;
    386       1.6     oster 
    387      1.27     oster #if RF_ACC_TRACE > 0
    388       1.6     oster 	RF_ETIMER_START(timer);
    389      1.27     oster #endif
    390      1.38     perry 
    391      1.32     oster 	/* acquire each lock that we don't already hold */
    392      1.32     oster 	for (asm_p = asmh->stripeMap; asm_p; asm_p = asm_p->next) {
    393      1.32     oster 		RF_ASSERT(RF_IO_IS_R_OR_W(desc->type));
    394      1.32     oster 		if (!rf_suppressLocksAndLargeWrites &&
    395      1.32     oster 		    asm_p->parityInfo &&
    396      1.32     oster 		    !(desc->flags & RF_DAG_SUPPRESS_LOCKS) &&
    397      1.32     oster 		    !(asm_p->flags & RF_ASM_FLAGS_LOCK_TRIED)) {
    398      1.32     oster 			asm_p->flags |= RF_ASM_FLAGS_LOCK_TRIED;
    399      1.23     oster 				/* locks must be acquired hierarchically */
    400      1.32     oster 			RF_ASSERT(asm_p->stripeID > lastStripeID);
    401      1.32     oster 			lastStripeID = asm_p->stripeID;
    402      1.38     perry 
    403      1.32     oster 			RF_INIT_LOCK_REQ_DESC(asm_p->lockReqDesc, desc->type,
    404      1.32     oster 					      (void (*) (struct buf *)) rf_ContinueRaidAccess, desc, asm_p,
    405      1.32     oster 					      raidPtr->Layout.dataSectorsPerStripe);
    406      1.32     oster 			if (rf_AcquireStripeLock(raidPtr->lockTable, asm_p->stripeID,
    407      1.32     oster 						 &asm_p->lockReqDesc)) {
    408      1.32     oster 				suspended = RF_TRUE;
    409      1.32     oster 				break;
    410      1.32     oster 			}
    411      1.32     oster 		}
    412      1.32     oster 		if (desc->type == RF_IO_TYPE_WRITE &&
    413      1.32     oster 		    raidPtr->status == rf_rs_reconstructing) {
    414      1.32     oster 			if (!(asm_p->flags & RF_ASM_FLAGS_FORCE_TRIED)) {
    415      1.32     oster 				int     val;
    416      1.38     perry 
    417      1.32     oster 				asm_p->flags |= RF_ASM_FLAGS_FORCE_TRIED;
    418      1.32     oster 				val = rf_ForceOrBlockRecon(raidPtr, asm_p,
    419      1.32     oster 							   (void (*) (RF_Raid_t *, void *)) rf_ContinueRaidAccess, desc);
    420      1.32     oster 				if (val == 0) {
    421      1.32     oster 					asm_p->flags |= RF_ASM_FLAGS_RECON_BLOCKED;
    422      1.32     oster 				} else {
    423       1.6     oster 					suspended = RF_TRUE;
    424       1.6     oster 					break;
    425       1.6     oster 				}
    426       1.6     oster 			} else {
    427      1.29     oster #if RF_DEBUG_PSS > 0
    428       1.6     oster 				if (rf_pssDebug) {
    429      1.32     oster 					printf("raid%d: skipping force/block because already done, psid %ld\n",
    430      1.38     perry 					       desc->raidPtr->raidid,
    431      1.13     oster 					       (long) asm_p->stripeID);
    432       1.6     oster 				}
    433      1.29     oster #endif
    434       1.6     oster 			}
    435      1.32     oster 		} else {
    436      1.32     oster #if RF_DEBUG_PSS > 0
    437      1.32     oster 			if (rf_pssDebug) {
    438      1.32     oster 				printf("raid%d: skipping force/block because not write or not under recon, psid %ld\n",
    439      1.38     perry 				       desc->raidPtr->raidid,
    440      1.32     oster 				       (long) asm_p->stripeID);
    441      1.32     oster 			}
    442      1.32     oster #endif
    443       1.6     oster 		}
    444      1.32     oster 	}
    445      1.27     oster #if RF_ACC_TRACE > 0
    446      1.32     oster 	RF_ETIMER_STOP(timer);
    447      1.32     oster 	RF_ETIMER_EVAL(timer);
    448      1.32     oster 	tracerec->specific.user.lock_us += RF_ETIMER_VAL_US(timer);
    449      1.27     oster #endif
    450      1.32     oster 	if (suspended)
    451      1.32     oster 		return (RF_TRUE);
    452      1.32     oster 
    453       1.6     oster 	desc->state++;
    454       1.6     oster 	return (RF_FALSE);
    455       1.1     oster }
    456       1.1     oster /*
    457       1.1     oster  * the following three states create, execute, and post-process dags
    458       1.1     oster  * the error recovery unit is a single dag.
    459       1.1     oster  * by default, SelectAlgorithm creates an array of dags, one per parity stripe
    460       1.1     oster  * in some tricky cases, multiple dags per stripe are created
    461       1.1     oster  *   - dags within a parity stripe are executed sequentially (arbitrary order)
    462       1.1     oster  *   - dags for distinct parity stripes are executed concurrently
    463       1.1     oster  *
    464       1.1     oster  * repeat until all dags complete successfully -or- dag selection fails
    465       1.1     oster  *
    466       1.1     oster  * while !done
    467       1.1     oster  *   create dag(s) (SelectAlgorithm)
    468       1.1     oster  *   if dag
    469       1.1     oster  *     execute dag (DispatchDAG)
    470       1.1     oster  *     if dag successful
    471       1.1     oster  *       done (SUCCESS)
    472       1.1     oster  *     else
    473       1.1     oster  *       !done (RETRY - start over with new dags)
    474       1.1     oster  *   else
    475       1.1     oster  *     done (FAIL)
    476       1.1     oster  */
    477      1.38     perry int
    478      1.22     oster rf_State_CreateDAG(RF_RaidAccessDesc_t *desc)
    479       1.1     oster {
    480      1.27     oster #if RF_ACC_TRACE > 0
    481       1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    482       1.6     oster 	RF_Etimer_t timer;
    483      1.27     oster #endif
    484       1.6     oster 	RF_DagHeader_t *dag_h;
    485      1.26     oster 	RF_DagList_t *dagList;
    486      1.25     oster 	struct buf *bp;
    487       1.6     oster 	int     i, selectStatus;
    488       1.6     oster 
    489       1.6     oster 	/* generate a dag for the access, and fire it off.  When the dag
    490       1.6     oster 	 * completes, we'll get re-invoked in the next state. */
    491      1.27     oster #if RF_ACC_TRACE > 0
    492       1.6     oster 	RF_ETIMER_START(timer);
    493      1.27     oster #endif
    494       1.6     oster 	/* SelectAlgorithm returns one or more dags */
    495       1.6     oster 	selectStatus = rf_SelectAlgorithm(desc, desc->flags | RF_DAG_SUPPRESS_LOCKS);
    496      1.17     oster #if RF_DEBUG_VALIDATE_DAG
    497      1.26     oster 	if (rf_printDAGsDebug) {
    498      1.26     oster 		dagList = desc->dagList;
    499      1.26     oster 		for (i = 0; i < desc->numStripes; i++) {
    500      1.26     oster 			rf_PrintDAGList(dagList.dags);
    501      1.26     oster 			dagList = dagList->next;
    502      1.26     oster 		}
    503      1.26     oster 	}
    504      1.17     oster #endif /* RF_DEBUG_VALIDATE_DAG */
    505      1.27     oster #if RF_ACC_TRACE > 0
    506       1.6     oster 	RF_ETIMER_STOP(timer);
    507       1.6     oster 	RF_ETIMER_EVAL(timer);
    508       1.6     oster 	/* update time to create all dags */
    509       1.6     oster 	tracerec->specific.user.dag_create_us = RF_ETIMER_VAL_US(timer);
    510      1.27     oster #endif
    511       1.6     oster 
    512       1.6     oster 	desc->status = 0;	/* good status */
    513       1.6     oster 
    514      1.36     oster 	if (selectStatus || (desc->numRetries > RF_RETRY_THRESHOLD)) {
    515       1.6     oster 		/* failed to create a dag */
    516       1.6     oster 		/* this happens when there are too many faults or incomplete
    517       1.6     oster 		 * dag libraries */
    518      1.36     oster 		if (selectStatus) {
    519      1.36     oster 			printf("raid%d: failed to create a dag. "
    520      1.38     perry 			       "Too many component failures.\n",
    521      1.36     oster 			       desc->raidPtr->raidid);
    522      1.36     oster 		} else {
    523      1.36     oster 			printf("raid%d: IO failed after %d retries.\n",
    524      1.36     oster 			       desc->raidPtr->raidid, RF_RETRY_THRESHOLD);
    525      1.36     oster 		}
    526      1.25     oster 
    527      1.38     perry 		desc->status = 1; /* bad status */
    528      1.25     oster 		/* skip straight to rf_State_Cleanup() */
    529      1.25     oster 		desc->state = rf_CleanupState;
    530      1.25     oster 		bp = (struct buf *)desc->bp;
    531      1.25     oster 		bp->b_error = EIO;
    532       1.6     oster 	} else {
    533       1.6     oster 		/* bind dags to desc */
    534      1.26     oster 		dagList = desc->dagList;
    535       1.6     oster 		for (i = 0; i < desc->numStripes; i++) {
    536      1.26     oster 			dag_h = dagList->dags;
    537       1.6     oster 			while (dag_h) {
    538       1.6     oster 				dag_h->bp = (struct buf *) desc->bp;
    539      1.27     oster #if RF_ACC_TRACE > 0
    540       1.6     oster 				dag_h->tracerec = tracerec;
    541      1.27     oster #endif
    542       1.6     oster 				dag_h = dag_h->next;
    543       1.6     oster 			}
    544      1.26     oster 			dagList = dagList->next;
    545       1.6     oster 		}
    546       1.6     oster 		desc->flags |= RF_DAG_DISPATCH_RETURNED;
    547       1.6     oster 		desc->state++;	/* next state should be rf_State_ExecuteDAG */
    548       1.6     oster 	}
    549       1.6     oster 	return RF_FALSE;
    550       1.1     oster }
    551       1.1     oster 
    552       1.1     oster 
    553       1.1     oster 
    554      1.26     oster /* the access has an list of dagLists, one dagList per parity stripe.
    555       1.1     oster  * fire the first dag in each parity stripe (dagList).
    556       1.1     oster  * dags within a stripe (dagList) must be executed sequentially
    557       1.1     oster  *  - this preserves atomic parity update
    558       1.1     oster  * dags for independents parity groups (stripes) are fired concurrently */
    559       1.1     oster 
    560      1.38     perry int
    561      1.22     oster rf_State_ExecuteDAG(RF_RaidAccessDesc_t *desc)
    562       1.1     oster {
    563       1.6     oster 	int     i;
    564       1.6     oster 	RF_DagHeader_t *dag_h;
    565      1.26     oster 	RF_DagList_t *dagList;
    566       1.6     oster 
    567      1.23     oster 	/* next state is always rf_State_ProcessDAG important to do
    568      1.23     oster 	 * this before firing the first dag (it may finish before we
    569      1.23     oster 	 * leave this routine) */
    570       1.6     oster 	desc->state++;
    571       1.6     oster 
    572      1.23     oster 	/* sweep dag array, a stripe at a time, firing the first dag
    573      1.23     oster 	 * in each stripe */
    574      1.26     oster 	dagList = desc->dagList;
    575       1.6     oster 	for (i = 0; i < desc->numStripes; i++) {
    576      1.26     oster 		RF_ASSERT(dagList->numDags > 0);
    577      1.26     oster 		RF_ASSERT(dagList->numDagsDone == 0);
    578      1.26     oster 		RF_ASSERT(dagList->numDagsFired == 0);
    579      1.27     oster #if RF_ACC_TRACE > 0
    580      1.26     oster 		RF_ETIMER_START(dagList->tracerec.timer);
    581      1.27     oster #endif
    582       1.6     oster 		/* fire first dag in this stripe */
    583      1.26     oster 		dag_h = dagList->dags;
    584       1.6     oster 		RF_ASSERT(dag_h);
    585      1.26     oster 		dagList->numDagsFired++;
    586      1.26     oster 		rf_DispatchDAG(dag_h, (void (*) (void *)) rf_ContinueDagAccess, dagList);
    587      1.26     oster 		dagList = dagList->next;
    588       1.6     oster 	}
    589       1.6     oster 
    590       1.6     oster 	/* the DAG will always call the callback, even if there was no
    591       1.6     oster 	 * blocking, so we are always suspended in this state */
    592       1.6     oster 	return RF_TRUE;
    593       1.1     oster }
    594       1.1     oster 
    595       1.1     oster 
    596       1.1     oster 
    597       1.1     oster /* rf_State_ProcessDAG is entered when a dag completes.
    598       1.1     oster  * first, check to all dags in the access have completed
    599       1.1     oster  * if not, fire as many dags as possible */
    600       1.1     oster 
    601      1.38     perry int
    602      1.22     oster rf_State_ProcessDAG(RF_RaidAccessDesc_t *desc)
    603       1.1     oster {
    604       1.6     oster 	RF_AccessStripeMapHeader_t *asmh = desc->asmap;
    605       1.6     oster 	RF_Raid_t *raidPtr = desc->raidPtr;
    606       1.6     oster 	RF_DagHeader_t *dag_h;
    607       1.6     oster 	int     i, j, done = RF_TRUE;
    608      1.26     oster 	RF_DagList_t *dagList, *temp;
    609       1.6     oster 
    610       1.6     oster 	/* check to see if this is the last dag */
    611      1.26     oster 	dagList = desc->dagList;
    612      1.26     oster 	for (i = 0; i < desc->numStripes; i++) {
    613      1.26     oster 		if (dagList->numDags != dagList->numDagsDone)
    614       1.6     oster 			done = RF_FALSE;
    615      1.26     oster 		dagList = dagList->next;
    616      1.26     oster 	}
    617       1.6     oster 
    618       1.6     oster 	if (done) {
    619       1.6     oster 		if (desc->status) {
    620       1.6     oster 			/* a dag failed, retry */
    621       1.6     oster 			/* free all dags */
    622      1.26     oster 			dagList = desc->dagList;
    623       1.6     oster 			for (i = 0; i < desc->numStripes; i++) {
    624      1.26     oster 				rf_FreeDAG(dagList->dags);
    625      1.26     oster 				temp = dagList;
    626      1.35     oster 				dagList = dagList->next;
    627      1.34     oster 				rf_FreeDAGList(temp);
    628       1.6     oster 			}
    629      1.37     oster 			desc->dagList = NULL;
    630      1.37     oster 
    631       1.6     oster 			rf_MarkFailuresInASMList(raidPtr, asmh);
    632      1.36     oster 
    633      1.36     oster 			/* note the retry so that we'll bail in
    634      1.36     oster 			   rf_State_CreateDAG() once we've retired
    635      1.36     oster 			   the IO RF_RETRY_THRESHOLD times */
    636      1.36     oster 
    637      1.36     oster 			desc->numRetries++;
    638      1.36     oster 
    639       1.6     oster 			/* back up to rf_State_CreateDAG */
    640       1.6     oster 			desc->state = desc->state - 2;
    641       1.6     oster 			return RF_FALSE;
    642       1.6     oster 		} else {
    643       1.6     oster 			/* move on to rf_State_Cleanup */
    644       1.6     oster 			desc->state++;
    645       1.6     oster 		}
    646       1.6     oster 		return RF_FALSE;
    647       1.6     oster 	} else {
    648       1.6     oster 		/* more dags to execute */
    649       1.6     oster 		/* see if any are ready to be fired.  if so, fire them */
    650       1.6     oster 		/* don't fire the initial dag in a list, it's fired in
    651       1.6     oster 		 * rf_State_ExecuteDAG */
    652      1.26     oster 		dagList = desc->dagList;
    653       1.6     oster 		for (i = 0; i < desc->numStripes; i++) {
    654      1.26     oster 			if ((dagList->numDagsDone < dagList->numDags)
    655      1.26     oster 			    && (dagList->numDagsDone == dagList->numDagsFired)
    656      1.26     oster 			    && (dagList->numDagsFired > 0)) {
    657      1.27     oster #if RF_ACC_TRACE > 0
    658      1.26     oster 				RF_ETIMER_START(dagList->tracerec.timer);
    659      1.27     oster #endif
    660       1.6     oster 				/* fire next dag in this stripe */
    661       1.6     oster 				/* first, skip to next dag awaiting execution */
    662      1.26     oster 				dag_h = dagList->dags;
    663      1.26     oster 				for (j = 0; j < dagList->numDagsDone; j++)
    664       1.6     oster 					dag_h = dag_h->next;
    665      1.26     oster 				dagList->numDagsFired++;
    666       1.6     oster 				rf_DispatchDAG(dag_h, (void (*) (void *)) rf_ContinueDagAccess,
    667      1.26     oster 				    dagList);
    668       1.6     oster 			}
    669      1.26     oster 			dagList = dagList->next;
    670       1.6     oster 		}
    671       1.6     oster 		return RF_TRUE;
    672       1.6     oster 	}
    673       1.1     oster }
    674       1.1     oster /* only make it this far if all dags complete successfully */
    675      1.38     perry int
    676      1.22     oster rf_State_Cleanup(RF_RaidAccessDesc_t *desc)
    677       1.1     oster {
    678      1.27     oster #if RF_ACC_TRACE > 0
    679       1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    680      1.28     oster 	RF_Etimer_t timer;
    681      1.27     oster #endif
    682       1.6     oster 	RF_AccessStripeMapHeader_t *asmh = desc->asmap;
    683       1.6     oster 	RF_Raid_t *raidPtr = desc->raidPtr;
    684       1.6     oster 	RF_AccessStripeMap_t *asm_p;
    685      1.26     oster 	RF_DagList_t *dagList;
    686      1.11     oster 	int i;
    687       1.6     oster 
    688       1.6     oster 	desc->state++;
    689       1.6     oster 
    690      1.27     oster #if RF_ACC_TRACE > 0
    691       1.6     oster 	timer = tracerec->timer;
    692       1.6     oster 	RF_ETIMER_STOP(timer);
    693       1.6     oster 	RF_ETIMER_EVAL(timer);
    694       1.6     oster 	tracerec->specific.user.dag_retry_us = RF_ETIMER_VAL_US(timer);
    695       1.6     oster 
    696       1.6     oster 	/* the RAID I/O is complete.  Clean up. */
    697       1.6     oster 	tracerec->specific.user.dag_retry_us = 0;
    698       1.6     oster 
    699       1.6     oster 	RF_ETIMER_START(timer);
    700      1.27     oster #endif
    701      1.24     oster 	/* free all dags */
    702      1.26     oster 	dagList = desc->dagList;
    703      1.24     oster 	for (i = 0; i < desc->numStripes; i++) {
    704      1.26     oster 		rf_FreeDAG(dagList->dags);
    705      1.26     oster 		dagList = dagList->next;
    706       1.6     oster 	}
    707      1.27     oster #if RF_ACC_TRACE > 0
    708       1.6     oster 	RF_ETIMER_STOP(timer);
    709       1.6     oster 	RF_ETIMER_EVAL(timer);
    710       1.6     oster 	tracerec->specific.user.cleanup_us = RF_ETIMER_VAL_US(timer);
    711       1.6     oster 
    712       1.6     oster 	RF_ETIMER_START(timer);
    713      1.27     oster #endif
    714      1.32     oster 	for (asm_p = asmh->stripeMap; asm_p; asm_p = asm_p->next) {
    715      1.32     oster 		if (!rf_suppressLocksAndLargeWrites &&
    716      1.32     oster 		    asm_p->parityInfo &&
    717      1.32     oster 		    !(desc->flags & RF_DAG_SUPPRESS_LOCKS)) {
    718      1.32     oster 			RF_ASSERT_VALID_LOCKREQ(&asm_p->lockReqDesc);
    719      1.38     perry 			rf_ReleaseStripeLock(raidPtr->lockTable,
    720      1.32     oster 					     asm_p->stripeID,
    721      1.32     oster 					     &asm_p->lockReqDesc);
    722      1.32     oster 		}
    723      1.32     oster 		if (asm_p->flags & RF_ASM_FLAGS_RECON_BLOCKED) {
    724      1.32     oster 			rf_UnblockRecon(raidPtr, asm_p);
    725       1.6     oster 		}
    726       1.6     oster 	}
    727      1.27     oster #if RF_ACC_TRACE > 0
    728       1.6     oster 	RF_ETIMER_STOP(timer);
    729       1.6     oster 	RF_ETIMER_EVAL(timer);
    730       1.6     oster 	tracerec->specific.user.lock_us += RF_ETIMER_VAL_US(timer);
    731       1.6     oster 
    732       1.6     oster 	RF_ETIMER_START(timer);
    733      1.27     oster #endif
    734      1.24     oster 	rf_FreeAccessStripeMap(asmh);
    735      1.27     oster #if RF_ACC_TRACE > 0
    736       1.6     oster 	RF_ETIMER_STOP(timer);
    737       1.6     oster 	RF_ETIMER_EVAL(timer);
    738       1.6     oster 	tracerec->specific.user.cleanup_us += RF_ETIMER_VAL_US(timer);
    739       1.6     oster 
    740       1.6     oster 	RF_ETIMER_STOP(desc->timer);
    741       1.6     oster 	RF_ETIMER_EVAL(desc->timer);
    742       1.6     oster 
    743       1.6     oster 	timer = desc->tracerec.tot_timer;
    744       1.6     oster 	RF_ETIMER_STOP(timer);
    745       1.6     oster 	RF_ETIMER_EVAL(timer);
    746       1.6     oster 	desc->tracerec.total_us = RF_ETIMER_VAL_US(timer);
    747       1.1     oster 
    748       1.6     oster 	rf_LogTraceRec(raidPtr, tracerec);
    749      1.27     oster #endif
    750       1.6     oster 	desc->flags |= RF_DAG_ACCESS_COMPLETE;
    751       1.1     oster 
    752       1.6     oster 	return RF_FALSE;
    753       1.1     oster }
    754