Home | History | Annotate | Line # | Download | only in raidframe
rf_states.c revision 1.52
      1 /*	$NetBSD: rf_states.c,v 1.52 2021/07/23 00:54:45 oster Exp $	*/
      2 /*
      3  * Copyright (c) 1995 Carnegie-Mellon University.
      4  * All rights reserved.
      5  *
      6  * Author: Mark Holland, William V. Courtright II, Robby Findler
      7  *
      8  * Permission to use, copy, modify and distribute this software and
      9  * its documentation is hereby granted, provided that both the copyright
     10  * notice and this permission notice appear in all copies of the
     11  * software, derivative works or modified versions, and any portions
     12  * thereof, and that both notices appear in supporting documentation.
     13  *
     14  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
     15  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
     16  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
     17  *
     18  * Carnegie Mellon requests users of this software to return to
     19  *
     20  *  Software Distribution Coordinator  or  Software.Distribution (at) CS.CMU.EDU
     21  *  School of Computer Science
     22  *  Carnegie Mellon University
     23  *  Pittsburgh PA 15213-3890
     24  *
     25  * any improvements or extensions that they make and grant Carnegie the
     26  * rights to redistribute these changes.
     27  */
     28 
     29 #include <sys/cdefs.h>
     30 __KERNEL_RCSID(0, "$NetBSD: rf_states.c,v 1.52 2021/07/23 00:54:45 oster Exp $");
     31 
     32 #include <sys/errno.h>
     33 
     34 #include "rf_archs.h"
     35 #include "rf_threadstuff.h"
     36 #include "rf_raid.h"
     37 #include "rf_dag.h"
     38 #include "rf_desc.h"
     39 #include "rf_aselect.h"
     40 #include "rf_general.h"
     41 #include "rf_states.h"
     42 #include "rf_dagutils.h"
     43 #include "rf_driver.h"
     44 #include "rf_engine.h"
     45 #include "rf_map.h"
     46 #include "rf_etimer.h"
     47 #include "rf_kintf.h"
     48 #include "rf_paritymap.h"
     49 
     50 #ifndef RF_DEBUG_STATES
     51 #define RF_DEBUG_STATES 0
     52 #endif
     53 
     54 /* prototypes for some of the available states.
     55 
     56    States must:
     57 
     58      - not block.
     59 
     60      - either schedule rf_ContinueRaidAccess as a callback and return
     61        RF_TRUE, or complete all of their work and return RF_FALSE.
     62 
     63      - increment desc->state when they have finished their work.
     64 */
     65 
     66 #if RF_DEBUG_STATES
     67 static char *
     68 StateName(RF_AccessState_t state)
     69 {
     70 	switch (state) {
     71 		case rf_QuiesceState:return "QuiesceState";
     72 	case rf_MapState:
     73 		return "MapState";
     74 	case rf_LockState:
     75 		return "LockState";
     76 	case rf_CreateDAGState:
     77 		return "CreateDAGState";
     78 	case rf_ExecuteDAGState:
     79 		return "ExecuteDAGState";
     80 	case rf_ProcessDAGState:
     81 		return "ProcessDAGState";
     82 	case rf_CleanupState:
     83 		return "CleanupState";
     84 	case rf_LastState:
     85 		return "LastState";
     86 	case rf_IncrAccessesCountState:
     87 		return "IncrAccessesCountState";
     88 	case rf_DecrAccessesCountState:
     89 		return "DecrAccessesCountState";
     90 	default:
     91 		return "!!! UnnamedState !!!";
     92 	}
     93 }
     94 #endif
     95 
     96 void
     97 rf_ContinueRaidAccess(void *v)
     98 {
     99 	RF_RaidAccessDesc_t *desc = v;
    100 	int     suspended = RF_FALSE;
    101 	int     current_state_index = desc->state;
    102 	RF_AccessState_t current_state = desc->states[current_state_index];
    103 #if RF_DEBUG_STATES
    104 	int     unit = desc->raidPtr->raidid;
    105 #endif
    106 
    107 	do {
    108 
    109 		current_state_index = desc->state;
    110 		current_state = desc->states[current_state_index];
    111 
    112 		switch (current_state) {
    113 
    114 		case rf_QuiesceState:
    115 			suspended = rf_State_Quiesce(desc);
    116 			break;
    117 		case rf_IncrAccessesCountState:
    118 			suspended = rf_State_IncrAccessCount(desc);
    119 			break;
    120 		case rf_MapState:
    121 			suspended = rf_State_Map(desc);
    122 			break;
    123 		case rf_LockState:
    124 			suspended = rf_State_Lock(desc);
    125 			break;
    126 		case rf_CreateDAGState:
    127 			suspended = rf_State_CreateDAG(desc);
    128 			break;
    129 		case rf_ExecuteDAGState:
    130 			suspended = rf_State_ExecuteDAG(desc);
    131 			break;
    132 		case rf_ProcessDAGState:
    133 			suspended = rf_State_ProcessDAG(desc);
    134 			break;
    135 		case rf_CleanupState:
    136 			suspended = rf_State_Cleanup(desc);
    137 			break;
    138 		case rf_DecrAccessesCountState:
    139 			suspended = rf_State_DecrAccessCount(desc);
    140 			break;
    141 		case rf_LastState:
    142 			suspended = rf_State_LastState(desc);
    143 			break;
    144 		}
    145 
    146 		/* after this point, we cannot dereference desc since
    147 		 * desc may have been freed. desc is only freed in
    148 		 * LastState, so if we renter this function or loop
    149 		 * back up, desc should be valid. */
    150 
    151 #if RF_DEBUG_STATES
    152 		if (rf_printStatesDebug) {
    153 			printf("raid%d: State: %-24s StateIndex: %3i desc: 0x%ld %s\n",
    154 			       unit, StateName(current_state),
    155 			       current_state_index, (long) desc,
    156 			       suspended ? "callback scheduled" : "looping");
    157 		}
    158 #endif
    159 	} while (!suspended && current_state != rf_LastState);
    160 
    161 	return;
    162 }
    163 
    164 
    165 void
    166 rf_ContinueDagAccess(RF_DagList_t *dagList)
    167 {
    168 #if RF_ACC_TRACE > 0
    169 	RF_AccTraceEntry_t *tracerec = &(dagList->desc->tracerec);
    170 	RF_Etimer_t timer;
    171 #endif
    172 	RF_RaidAccessDesc_t *desc;
    173 	RF_DagHeader_t *dag_h;
    174 	int     i;
    175 
    176 	desc = dagList->desc;
    177 
    178 #if RF_ACC_TRACE > 0
    179 	timer = tracerec->timer;
    180 	RF_ETIMER_STOP(timer);
    181 	RF_ETIMER_EVAL(timer);
    182 	tracerec->specific.user.exec_us = RF_ETIMER_VAL_US(timer);
    183 	RF_ETIMER_START(tracerec->timer);
    184 #endif
    185 
    186 	/* skip to dag which just finished */
    187 	dag_h = dagList->dags;
    188 	for (i = 0; i < dagList->numDagsDone; i++) {
    189 		dag_h = dag_h->next;
    190 	}
    191 
    192 	/* check to see if retry is required */
    193 	if (dag_h->status == rf_rollBackward) {
    194 		/* when a dag fails, mark desc status as bad and allow
    195 		 * all other dags in the desc to execute to
    196 		 * completion.  then, free all dags and start over */
    197 		desc->status = 1;	/* bad status */
    198 #if 0
    199 		printf("raid%d: DAG failure: %c addr 0x%lx "
    200 		       "(%ld) nblk 0x%x (%d) buf 0x%lx state %d\n",
    201 		       desc->raidPtr->raidid, desc->type,
    202 		       (long) desc->raidAddress,
    203 		       (long) desc->raidAddress, (int) desc->numBlocks,
    204 		       (int) desc->numBlocks,
    205 		       (unsigned long) (desc->bufPtr), desc->state);
    206 #endif
    207 	}
    208 	dagList->numDagsDone++;
    209 	rf_ContinueRaidAccess(desc);
    210 }
    211 
    212 int
    213 rf_State_LastState(RF_RaidAccessDesc_t *desc)
    214 {
    215 	void    (*callbackFunc) (void *) = desc->callbackFunc;
    216 	void * callbackArg = desc->callbackArg;
    217 
    218 	/*
    219 	 * We don't support non-async IO.
    220 	 */
    221 	KASSERT(desc->async_flag);
    222 
    223 	/*
    224 	 * The parity_map hook has to go here, because the iodone
    225 	 * callback goes straight into the kintf layer.
    226 	 */
    227 	if (desc->raidPtr->parity_map != NULL &&
    228 	    desc->type == RF_IO_TYPE_WRITE)
    229 		rf_paritymap_end(desc->raidPtr->parity_map,
    230 		    desc->raidAddress, desc->numBlocks);
    231 
    232 	/* printf("Calling raiddone on 0x%x\n",desc->bp); */
    233 	raiddone(desc->raidPtr, desc->bp); /* access came through ioctl */
    234 
    235 	if (callbackFunc)
    236 		callbackFunc(callbackArg);
    237 	rf_FreeRaidAccDesc(desc);
    238 
    239 	return RF_FALSE;
    240 }
    241 
    242 int
    243 rf_State_IncrAccessCount(RF_RaidAccessDesc_t *desc)
    244 {
    245 	RF_Raid_t *raidPtr;
    246 
    247 	raidPtr = desc->raidPtr;
    248 	/* Bummer. We have to do this to be 100% safe w.r.t. the increment
    249 	 * below */
    250 	rf_lock_mutex2(raidPtr->access_suspend_mutex);
    251 	raidPtr->accs_in_flight++;	/* used to detect quiescence */
    252 	rf_unlock_mutex2(raidPtr->access_suspend_mutex);
    253 
    254 	desc->state++;
    255 	return RF_FALSE;
    256 }
    257 
    258 int
    259 rf_State_DecrAccessCount(RF_RaidAccessDesc_t *desc)
    260 {
    261 	RF_Raid_t *raidPtr;
    262 
    263 	raidPtr = desc->raidPtr;
    264 
    265 	rf_lock_mutex2(raidPtr->access_suspend_mutex);
    266 	raidPtr->accs_in_flight--;
    267 	if (raidPtr->accesses_suspended && raidPtr->accs_in_flight == 0) {
    268 		rf_SignalQuiescenceLock(raidPtr);
    269 	}
    270 	rf_unlock_mutex2(raidPtr->access_suspend_mutex);
    271 
    272 	desc->state++;
    273 	return RF_FALSE;
    274 }
    275 
    276 int
    277 rf_State_Quiesce(RF_RaidAccessDesc_t *desc)
    278 {
    279 #if RF_ACC_TRACE > 0
    280 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    281 	RF_Etimer_t timer;
    282 #endif
    283 	RF_CallbackFuncDesc_t *cb;
    284 	RF_Raid_t *raidPtr;
    285 	int     suspended = RF_FALSE;
    286 	int need_cb, used_cb;
    287 
    288 	raidPtr = desc->raidPtr;
    289 
    290 #if RF_ACC_TRACE > 0
    291 	RF_ETIMER_START(timer);
    292 	RF_ETIMER_START(desc->timer);
    293 #endif
    294 
    295 	need_cb = 0;
    296 	used_cb = 0;
    297 	cb = NULL;
    298 
    299 	rf_lock_mutex2(raidPtr->access_suspend_mutex);
    300 	/* Do an initial check to see if we might need a callback structure */
    301 	if (raidPtr->accesses_suspended) {
    302 		need_cb = 1;
    303 	}
    304 	rf_unlock_mutex2(raidPtr->access_suspend_mutex);
    305 
    306 	if (need_cb) {
    307 		/* create a callback if we might need it...
    308 		   and we likely do. */
    309 		cb = rf_AllocCallbackFuncDesc(raidPtr);
    310 	}
    311 
    312 	rf_lock_mutex2(raidPtr->access_suspend_mutex);
    313 	if (raidPtr->accesses_suspended) {
    314 		cb->callbackFunc = rf_ContinueRaidAccess;
    315 		cb->callbackArg = desc;
    316 		cb->next = raidPtr->quiesce_wait_list;
    317 		raidPtr->quiesce_wait_list = cb;
    318 		suspended = RF_TRUE;
    319 		used_cb = 1;
    320 	}
    321 	rf_unlock_mutex2(raidPtr->access_suspend_mutex);
    322 
    323 	if ((need_cb == 1) && (used_cb == 0)) {
    324 		rf_FreeCallbackFuncDesc(raidPtr, cb);
    325 	}
    326 
    327 #if RF_ACC_TRACE > 0
    328 	RF_ETIMER_STOP(timer);
    329 	RF_ETIMER_EVAL(timer);
    330 	tracerec->specific.user.suspend_ovhd_us += RF_ETIMER_VAL_US(timer);
    331 #endif
    332 
    333 #if RF_DEBUG_QUIESCE
    334 	if (suspended && rf_quiesceDebug)
    335 		printf("Stalling access due to quiescence lock\n");
    336 #endif
    337 	desc->state++;
    338 	return suspended;
    339 }
    340 
    341 int
    342 rf_State_Map(RF_RaidAccessDesc_t *desc)
    343 {
    344 	RF_Raid_t *raidPtr = desc->raidPtr;
    345 #if RF_ACC_TRACE > 0
    346 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    347 	RF_Etimer_t timer;
    348 
    349 	RF_ETIMER_START(timer);
    350 #endif
    351 
    352 	if (!(desc->asmap = rf_MapAccess(raidPtr, desc->raidAddress, desc->numBlocks,
    353 		    desc->bufPtr, RF_DONT_REMAP)))
    354 		RF_PANIC();
    355 
    356 #if RF_ACC_TRACE > 0
    357 	RF_ETIMER_STOP(timer);
    358 	RF_ETIMER_EVAL(timer);
    359 	tracerec->specific.user.map_us = RF_ETIMER_VAL_US(timer);
    360 #endif
    361 
    362 	desc->state++;
    363 	return RF_FALSE;
    364 }
    365 
    366 int
    367 rf_State_Lock(RF_RaidAccessDesc_t *desc)
    368 {
    369 #if RF_ACC_TRACE > 0
    370 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    371 	RF_Etimer_t timer;
    372 #endif
    373 	RF_Raid_t *raidPtr = desc->raidPtr;
    374 	RF_AccessStripeMapHeader_t *asmh = desc->asmap;
    375 	RF_AccessStripeMap_t *asm_p;
    376 	RF_StripeNum_t lastStripeID = -1;
    377 	int     suspended = RF_FALSE;
    378 
    379 #if RF_ACC_TRACE > 0
    380 	RF_ETIMER_START(timer);
    381 #endif
    382 
    383 	/* acquire each lock that we don't already hold */
    384 	for (asm_p = asmh->stripeMap; asm_p; asm_p = asm_p->next) {
    385 		RF_ASSERT(RF_IO_IS_R_OR_W(desc->type));
    386 		if (!rf_suppressLocksAndLargeWrites &&
    387 		    asm_p->parityInfo &&
    388 		    !(desc->flags & RF_DAG_SUPPRESS_LOCKS) &&
    389 		    !(asm_p->flags & RF_ASM_FLAGS_LOCK_TRIED)) {
    390 			asm_p->flags |= RF_ASM_FLAGS_LOCK_TRIED;
    391 				/* locks must be acquired hierarchically */
    392 			RF_ASSERT(asm_p->stripeID > lastStripeID);
    393 			lastStripeID = asm_p->stripeID;
    394 
    395 			RF_INIT_LOCK_REQ_DESC(asm_p->lockReqDesc, desc->type,
    396 					      rf_ContinueRaidAccess, desc, asm_p,
    397 					      raidPtr->Layout.dataSectorsPerStripe);
    398 			if (rf_AcquireStripeLock(raidPtr, raidPtr->lockTable, asm_p->stripeID,
    399 						 &asm_p->lockReqDesc)) {
    400 				suspended = RF_TRUE;
    401 				break;
    402 			}
    403 		}
    404 		if (desc->type == RF_IO_TYPE_WRITE &&
    405 		    raidPtr->status == rf_rs_reconstructing) {
    406 			if (!(asm_p->flags & RF_ASM_FLAGS_FORCE_TRIED)) {
    407 				int     val;
    408 
    409 				asm_p->flags |= RF_ASM_FLAGS_FORCE_TRIED;
    410 				val = rf_ForceOrBlockRecon(raidPtr, asm_p,
    411 							   rf_ContinueRaidAccess, desc);
    412 				if (val == 0) {
    413 					asm_p->flags |= RF_ASM_FLAGS_RECON_BLOCKED;
    414 				} else {
    415 					suspended = RF_TRUE;
    416 					break;
    417 				}
    418 			} else {
    419 #if RF_DEBUG_PSS > 0
    420 				if (rf_pssDebug) {
    421 					printf("raid%d: skipping force/block because already done, psid %ld\n",
    422 					       desc->raidPtr->raidid,
    423 					       (long) asm_p->stripeID);
    424 				}
    425 #endif
    426 			}
    427 		} else {
    428 #if RF_DEBUG_PSS > 0
    429 			if (rf_pssDebug) {
    430 				printf("raid%d: skipping force/block because not write or not under recon, psid %ld\n",
    431 				       desc->raidPtr->raidid,
    432 				       (long) asm_p->stripeID);
    433 			}
    434 #endif
    435 		}
    436 	}
    437 #if RF_ACC_TRACE > 0
    438 	RF_ETIMER_STOP(timer);
    439 	RF_ETIMER_EVAL(timer);
    440 	tracerec->specific.user.lock_us += RF_ETIMER_VAL_US(timer);
    441 #endif
    442 	if (suspended)
    443 		return (RF_TRUE);
    444 
    445 	desc->state++;
    446 	return (RF_FALSE);
    447 }
    448 /*
    449  * the following three states create, execute, and post-process dags
    450  * the error recovery unit is a single dag.
    451  * by default, SelectAlgorithm creates an array of dags, one per parity stripe
    452  * in some tricky cases, multiple dags per stripe are created
    453  *   - dags within a parity stripe are executed sequentially (arbitrary order)
    454  *   - dags for distinct parity stripes are executed concurrently
    455  *
    456  * repeat until all dags complete successfully -or- dag selection fails
    457  *
    458  * while !done
    459  *   create dag(s) (SelectAlgorithm)
    460  *   if dag
    461  *     execute dag (DispatchDAG)
    462  *     if dag successful
    463  *       done (SUCCESS)
    464  *     else
    465  *       !done (RETRY - start over with new dags)
    466  *   else
    467  *     done (FAIL)
    468  */
    469 int
    470 rf_State_CreateDAG(RF_RaidAccessDesc_t *desc)
    471 {
    472 #if RF_ACC_TRACE > 0
    473 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    474 	RF_Etimer_t timer;
    475 #endif
    476 	RF_DagHeader_t *dag_h;
    477 	RF_DagList_t *dagList;
    478 	struct buf *bp;
    479 	int     i, selectStatus;
    480 
    481 	/* generate a dag for the access, and fire it off.  When the dag
    482 	 * completes, we'll get re-invoked in the next state. */
    483 #if RF_ACC_TRACE > 0
    484 	RF_ETIMER_START(timer);
    485 #endif
    486 	/* SelectAlgorithm returns one or more dags */
    487 	selectStatus = rf_SelectAlgorithm(desc, desc->flags | RF_DAG_SUPPRESS_LOCKS);
    488 #if RF_DEBUG_VALIDATE_DAG
    489 	if (rf_printDAGsDebug) {
    490 		dagList = desc->dagList;
    491 		for (i = 0; i < desc->numStripes; i++) {
    492 			rf_PrintDAGList(dagList->dags);
    493 			dagList = dagList->next;
    494 		}
    495 	}
    496 #endif /* RF_DEBUG_VALIDATE_DAG */
    497 #if RF_ACC_TRACE > 0
    498 	RF_ETIMER_STOP(timer);
    499 	RF_ETIMER_EVAL(timer);
    500 	/* update time to create all dags */
    501 	tracerec->specific.user.dag_create_us = RF_ETIMER_VAL_US(timer);
    502 #endif
    503 
    504 	desc->status = 0;	/* good status */
    505 
    506 	if (selectStatus || (desc->numRetries > RF_RETRY_THRESHOLD)) {
    507 		/* failed to create a dag */
    508 		/* this happens when there are too many faults or incomplete
    509 		 * dag libraries */
    510 		if (selectStatus) {
    511 			printf("raid%d: failed to create a dag. "
    512 			       "Too many component failures.\n",
    513 			       desc->raidPtr->raidid);
    514 		} else {
    515 			printf("raid%d: IO failed after %d retries.\n",
    516 			       desc->raidPtr->raidid, RF_RETRY_THRESHOLD);
    517 		}
    518 
    519 		desc->status = 1; /* bad status */
    520 		/* skip straight to rf_State_Cleanup() */
    521 		desc->state = rf_CleanupState;
    522 		bp = (struct buf *)desc->bp;
    523 		bp->b_error = EIO;
    524 		bp->b_resid = bp->b_bcount;
    525 	} else {
    526 		/* bind dags to desc */
    527 		dagList = desc->dagList;
    528 		for (i = 0; i < desc->numStripes; i++) {
    529 			dag_h = dagList->dags;
    530 			while (dag_h) {
    531 				dag_h->bp = (struct buf *) desc->bp;
    532 #if RF_ACC_TRACE > 0
    533 				dag_h->tracerec = tracerec;
    534 #endif
    535 				dag_h = dag_h->next;
    536 			}
    537 			dagList = dagList->next;
    538 		}
    539 		desc->flags |= RF_DAG_DISPATCH_RETURNED;
    540 		desc->state++;	/* next state should be rf_State_ExecuteDAG */
    541 	}
    542 	return RF_FALSE;
    543 }
    544 
    545 
    546 
    547 /* the access has an list of dagLists, one dagList per parity stripe.
    548  * fire the first dag in each parity stripe (dagList).
    549  * dags within a stripe (dagList) must be executed sequentially
    550  *  - this preserves atomic parity update
    551  * dags for independents parity groups (stripes) are fired concurrently */
    552 
    553 int
    554 rf_State_ExecuteDAG(RF_RaidAccessDesc_t *desc)
    555 {
    556 	int     i;
    557 	RF_DagHeader_t *dag_h;
    558 	RF_DagList_t *dagList;
    559 
    560 	/* next state is always rf_State_ProcessDAG important to do
    561 	 * this before firing the first dag (it may finish before we
    562 	 * leave this routine) */
    563 	desc->state++;
    564 
    565 	/* sweep dag array, a stripe at a time, firing the first dag
    566 	 * in each stripe */
    567 	dagList = desc->dagList;
    568 	for (i = 0; i < desc->numStripes; i++) {
    569 		RF_ASSERT(dagList->numDags > 0);
    570 		RF_ASSERT(dagList->numDagsDone == 0);
    571 		RF_ASSERT(dagList->numDagsFired == 0);
    572 #if RF_ACC_TRACE > 0
    573 		RF_ETIMER_START(dagList->tracerec.timer);
    574 #endif
    575 		/* fire first dag in this stripe */
    576 		dag_h = dagList->dags;
    577 		RF_ASSERT(dag_h);
    578 		dagList->numDagsFired++;
    579 		rf_DispatchDAG(dag_h, (void (*) (void *)) rf_ContinueDagAccess, dagList);
    580 		dagList = dagList->next;
    581 	}
    582 
    583 	/* the DAG will always call the callback, even if there was no
    584 	 * blocking, so we are always suspended in this state */
    585 	return RF_TRUE;
    586 }
    587 
    588 
    589 
    590 /* rf_State_ProcessDAG is entered when a dag completes.
    591  * first, check to all dags in the access have completed
    592  * if not, fire as many dags as possible */
    593 
    594 int
    595 rf_State_ProcessDAG(RF_RaidAccessDesc_t *desc)
    596 {
    597 	RF_AccessStripeMapHeader_t *asmh = desc->asmap;
    598 	RF_Raid_t *raidPtr = desc->raidPtr;
    599 	RF_DagHeader_t *dag_h;
    600 	int     i, j, done = RF_TRUE;
    601 	RF_DagList_t *dagList, *temp;
    602 
    603 	/* check to see if this is the last dag */
    604 	dagList = desc->dagList;
    605 	for (i = 0; i < desc->numStripes; i++) {
    606 		if (dagList->numDags != dagList->numDagsDone)
    607 			done = RF_FALSE;
    608 		dagList = dagList->next;
    609 	}
    610 
    611 	if (done) {
    612 		if (desc->status) {
    613 			/* a dag failed, retry */
    614 			/* free all dags */
    615 			dagList = desc->dagList;
    616 			for (i = 0; i < desc->numStripes; i++) {
    617 				rf_FreeDAG(dagList->dags);
    618 				temp = dagList;
    619 				dagList = dagList->next;
    620 				rf_FreeDAGList(raidPtr, temp);
    621 			}
    622 			desc->dagList = NULL;
    623 
    624 			rf_MarkFailuresInASMList(raidPtr, asmh);
    625 
    626 			/* note the retry so that we'll bail in
    627 			   rf_State_CreateDAG() once we've retired
    628 			   the IO RF_RETRY_THRESHOLD times */
    629 
    630 			desc->numRetries++;
    631 
    632 			/* back up to rf_State_CreateDAG */
    633 			desc->state = desc->state - 2;
    634 			return RF_FALSE;
    635 		} else {
    636 			/* move on to rf_State_Cleanup */
    637 			desc->state++;
    638 		}
    639 		return RF_FALSE;
    640 	} else {
    641 		/* more dags to execute */
    642 		/* see if any are ready to be fired.  if so, fire them */
    643 		/* don't fire the initial dag in a list, it's fired in
    644 		 * rf_State_ExecuteDAG */
    645 		dagList = desc->dagList;
    646 		for (i = 0; i < desc->numStripes; i++) {
    647 			if ((dagList->numDagsDone < dagList->numDags)
    648 			    && (dagList->numDagsDone == dagList->numDagsFired)
    649 			    && (dagList->numDagsFired > 0)) {
    650 #if RF_ACC_TRACE > 0
    651 				RF_ETIMER_START(dagList->tracerec.timer);
    652 #endif
    653 				/* fire next dag in this stripe */
    654 				/* first, skip to next dag awaiting execution */
    655 				dag_h = dagList->dags;
    656 				for (j = 0; j < dagList->numDagsDone; j++)
    657 					dag_h = dag_h->next;
    658 				dagList->numDagsFired++;
    659 				rf_DispatchDAG(dag_h, (void (*) (void *)) rf_ContinueDagAccess,
    660 				    dagList);
    661 			}
    662 			dagList = dagList->next;
    663 		}
    664 		return RF_TRUE;
    665 	}
    666 }
    667 /* only make it this far if all dags complete successfully */
    668 int
    669 rf_State_Cleanup(RF_RaidAccessDesc_t *desc)
    670 {
    671 #if RF_ACC_TRACE > 0
    672 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    673 	RF_Etimer_t timer;
    674 #endif
    675 	RF_AccessStripeMapHeader_t *asmh = desc->asmap;
    676 	RF_Raid_t *raidPtr = desc->raidPtr;
    677 	RF_AccessStripeMap_t *asm_p;
    678 	RF_DagList_t *dagList;
    679 	int i;
    680 
    681 	desc->state++;
    682 
    683 #if RF_ACC_TRACE > 0
    684 	timer = tracerec->timer;
    685 	RF_ETIMER_STOP(timer);
    686 	RF_ETIMER_EVAL(timer);
    687 	tracerec->specific.user.dag_retry_us = RF_ETIMER_VAL_US(timer);
    688 
    689 	/* the RAID I/O is complete.  Clean up. */
    690 	tracerec->specific.user.dag_retry_us = 0;
    691 
    692 	RF_ETIMER_START(timer);
    693 #endif
    694 	/* free all dags */
    695 	dagList = desc->dagList;
    696 	for (i = 0; i < desc->numStripes; i++) {
    697 		rf_FreeDAG(dagList->dags);
    698 		dagList = dagList->next;
    699 	}
    700 #if RF_ACC_TRACE > 0
    701 	RF_ETIMER_STOP(timer);
    702 	RF_ETIMER_EVAL(timer);
    703 	tracerec->specific.user.cleanup_us = RF_ETIMER_VAL_US(timer);
    704 
    705 	RF_ETIMER_START(timer);
    706 #endif
    707 	for (asm_p = asmh->stripeMap; asm_p; asm_p = asm_p->next) {
    708 		if (!rf_suppressLocksAndLargeWrites &&
    709 		    asm_p->parityInfo &&
    710 		    !(desc->flags & RF_DAG_SUPPRESS_LOCKS)) {
    711 			RF_ASSERT_VALID_LOCKREQ(&asm_p->lockReqDesc);
    712 			rf_ReleaseStripeLock(raidPtr,
    713 					     raidPtr->lockTable,
    714 					     asm_p->stripeID,
    715 					     &asm_p->lockReqDesc);
    716 		}
    717 		if (asm_p->flags & RF_ASM_FLAGS_RECON_BLOCKED) {
    718 			rf_UnblockRecon(raidPtr, asm_p);
    719 		}
    720 	}
    721 #if RF_ACC_TRACE > 0
    722 	RF_ETIMER_STOP(timer);
    723 	RF_ETIMER_EVAL(timer);
    724 	tracerec->specific.user.lock_us += RF_ETIMER_VAL_US(timer);
    725 
    726 	RF_ETIMER_START(timer);
    727 #endif
    728 	rf_FreeAccessStripeMap(raidPtr, asmh);
    729 #if RF_ACC_TRACE > 0
    730 	RF_ETIMER_STOP(timer);
    731 	RF_ETIMER_EVAL(timer);
    732 	tracerec->specific.user.cleanup_us += RF_ETIMER_VAL_US(timer);
    733 
    734 	RF_ETIMER_STOP(desc->timer);
    735 	RF_ETIMER_EVAL(desc->timer);
    736 
    737 	timer = desc->tracerec.tot_timer;
    738 	RF_ETIMER_STOP(timer);
    739 	RF_ETIMER_EVAL(timer);
    740 	desc->tracerec.total_us = RF_ETIMER_VAL_US(timer);
    741 
    742 	rf_LogTraceRec(raidPtr, tracerec);
    743 #endif
    744 	desc->flags |= RF_DAG_ACCESS_COMPLETE;
    745 
    746 	return RF_FALSE;
    747 }
    748