summaryrefslogtreecommitdiff
path: root/gnu/dist/postfix/src/util/doze.c
diff options
context:
space:
mode:
Diffstat (limited to 'gnu/dist/postfix/src/util/doze.c')
0 files changed, 0 insertions, 0 deletions
61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478
/*	$NetBSD: rf_reconbuffer.c,v 1.7 2002/01/09 03:10:20 oster Exp $	*/
/*
 * Copyright (c) 1995 Carnegie-Mellon University.
 * All rights reserved.
 *
 * Author: Mark Holland
 *
 * Permission to use, copy, modify and distribute this software and
 * its documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 *
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 *
 * Carnegie Mellon requests users of this software to return to
 *
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 *
 * any improvements or extensions that they make and grant Carnegie the
 * rights to redistribute these changes.
 */

/***************************************************
 *
 * rf_reconbuffer.c -- reconstruction buffer manager
 *
 ***************************************************/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: rf_reconbuffer.c,v 1.7 2002/01/09 03:10:20 oster Exp $");

#include "rf_raid.h"
#include "rf_reconbuffer.h"
#include "rf_acctrace.h"
#include "rf_etimer.h"
#include "rf_general.h"
#include "rf_debugprint.h"
#include "rf_revent.h"
#include "rf_reconutil.h"
#include "rf_nwayxor.h"

#ifdef DEBUG

#define Dprintf1(s,a) if (rf_reconbufferDebug) printf(s,a)
#define Dprintf2(s,a,b) if (rf_reconbufferDebug) printf(s,a,b)
#define Dprintf3(s,a,b,c) if (rf_reconbufferDebug) printf(s,a,b,c)
#define Dprintf4(s,a,b,c,d) if (rf_reconbufferDebug) printf(s,a,b,c,d)
#define Dprintf5(s,a,b,c,d,e) if (rf_reconbufferDebug) printf(s,a,b,c,d,e)

#else /* DEBUG */

#define Dprintf1(s,a) {}
#define Dprintf2(s,a,b) {}
#define Dprintf3(s,a,b,c) {}
#define Dprintf4(s,a,b,c,d) {}
#define Dprintf5(s,a,b,c,d,e) {}

#endif

/*****************************************************************************
 *
 * Submit a reconstruction buffer to the manager for XOR.  We can only
 * submit a buffer if (1) we can xor into an existing buffer, which
 * means we don't have to acquire a new one, (2) we can acquire a
 * floating recon buffer, or (3) the caller has indicated that we are
 * allowed to keep the submitted buffer.
 *
 * Returns non-zero if and only if we were not able to submit.
 * In this case, we append the current disk ID to the wait list on the
 * indicated RU, so that it will be re-enabled when we acquire a buffer 
 * for this RU.
 *
 ****************************************************************************/

/*
 * nWayXorFuncs[i] is a pointer to a function that will xor "i"
 * bufs into the accumulating sum.
 */
static RF_VoidFuncPtr nWayXorFuncs[] = {
	NULL,
	(RF_VoidFuncPtr) rf_nWayXor1,
	(RF_VoidFuncPtr) rf_nWayXor2,
	(RF_VoidFuncPtr) rf_nWayXor3,
	(RF_VoidFuncPtr) rf_nWayXor4,
	(RF_VoidFuncPtr) rf_nWayXor5,
	(RF_VoidFuncPtr) rf_nWayXor6,
	(RF_VoidFuncPtr) rf_nWayXor7,
	(RF_VoidFuncPtr) rf_nWayXor8,
	(RF_VoidFuncPtr) rf_nWayXor9
};

int 
rf_SubmitReconBuffer(rbuf, keep_it, use_committed)
	RF_ReconBuffer_t *rbuf;	/* the recon buffer to submit */
	int     keep_it;	/* whether we can keep this buffer or we have
				 * to return it */
	int     use_committed;	/* whether to use a committed or an available
				 * recon buffer */
{
	RF_LayoutSW_t *lp;
	int     rc;

	lp = rbuf->raidPtr->Layout.map;
	rc = lp->SubmitReconBuffer(rbuf, keep_it, use_committed);
	return (rc);
}

int 
rf_SubmitReconBufferBasic(rbuf, keep_it, use_committed)
	RF_ReconBuffer_t *rbuf;	/* the recon buffer to submit */
	int     keep_it;	/* whether we can keep this buffer or we have
				 * to return it */
	int     use_committed;	/* whether to use a committed or an available
				 * recon buffer */
{
	RF_Raid_t *raidPtr = rbuf->raidPtr;
	RF_RaidLayout_t *layoutPtr = &raidPtr->Layout;
	RF_ReconCtrl_t *reconCtrlPtr = raidPtr->reconControl[rbuf->row];
	RF_ReconParityStripeStatus_t *pssPtr;
	RF_ReconBuffer_t *targetRbuf, *t = NULL;	/* temporary rbuf
							 * pointers */
	caddr_t ta;		/* temporary data buffer pointer */
	RF_CallbackDesc_t *cb, *p;
	int     retcode = 0, created = 0;

	RF_Etimer_t timer;

	/* makes no sense to have a submission from the failed disk */
	RF_ASSERT(rbuf);
	RF_ASSERT(rbuf->col != reconCtrlPtr->fcol);

	Dprintf5("RECON: submission by row %d col %d for psid %ld ru %d (failed offset %ld)\n",
	    rbuf->row, rbuf->col, (long) rbuf->parityStripeID, rbuf->which_ru, (long) rbuf->failedDiskSectorOffset);

	RF_LOCK_PSS_MUTEX(raidPtr, rbuf->row, rbuf->parityStripeID);

	RF_LOCK_MUTEX(reconCtrlPtr->rb_mutex);

	pssPtr = rf_LookupRUStatus(raidPtr, reconCtrlPtr->pssTable, rbuf->parityStripeID, rbuf->which_ru, RF_PSS_NONE, &created);
	RF_ASSERT(pssPtr);	/* if it didn't exist, we wouldn't have gotten
				 * an rbuf for it */

	/* check to see if enough buffers have accumulated to do an XOR.  If
	 * so, there's no need to acquire a floating rbuf.  Before we can do
	 * any XORing, we must have acquired a destination buffer.  If we
	 * have, then we can go ahead and do the XOR if (1) including this
	 * buffer, enough bufs have accumulated, or (2) this is the last
	 * submission for this stripe. Otherwise, we have to go acquire a
	 * floating rbuf. */

	targetRbuf = (RF_ReconBuffer_t *) pssPtr->rbuf;
	if ((targetRbuf != NULL) &&
	    ((pssPtr->xorBufCount == rf_numBufsToAccumulate - 1) || (targetRbuf->count + pssPtr->xorBufCount + 1 == layoutPtr->numDataCol))) {
		pssPtr->rbufsForXor[pssPtr->xorBufCount++] = rbuf;	/* install this buffer */
		Dprintf3("RECON: row %d col %d invoking a %d-way XOR\n", rbuf->row, rbuf->col, pssPtr->xorBufCount);
		RF_ETIMER_START(timer);
		rf_MultiWayReconXor(raidPtr, pssPtr);
		RF_ETIMER_STOP(timer);
		RF_ETIMER_EVAL(timer);
		raidPtr->accumXorTimeUs += RF_ETIMER_VAL_US(timer);
		if (!keep_it) {
			raidPtr->recon_tracerecs[rbuf->col].xor_us = RF_ETIMER_VAL_US(timer);
			RF_ETIMER_STOP(raidPtr->recon_tracerecs[rbuf->col].recon_timer);
			RF_ETIMER_EVAL(raidPtr->recon_tracerecs[rbuf->col].recon_timer);
			raidPtr->recon_tracerecs[rbuf->col].specific.recon.recon_return_to_submit_us +=
			    RF_ETIMER_VAL_US(raidPtr->recon_tracerecs[rbuf->col].recon_timer);
			RF_ETIMER_START(raidPtr->recon_tracerecs[rbuf->col].recon_timer);

			rf_LogTraceRec(raidPtr, &raidPtr->recon_tracerecs[rbuf->col]);
		}
		rf_CheckForFullRbuf(raidPtr, reconCtrlPtr, pssPtr, layoutPtr->numDataCol);

		/* if use_committed is on, we _must_ consume a buffer off the
		 * committed list. */
		if (use_committed) {
			t = reconCtrlPtr->committedRbufs;
			RF_ASSERT(t);
			reconCtrlPtr->committedRbufs = t->next;
			rf_ReleaseFloatingReconBuffer(raidPtr, rbuf->row, t);
		}
		if (keep_it) {
			RF_UNLOCK_PSS_MUTEX(raidPtr, rbuf->row, rbuf->parityStripeID);
			RF_UNLOCK_MUTEX(reconCtrlPtr->rb_mutex);
			rf_FreeReconBuffer(rbuf);
			return (retcode);
		}
		goto out;
	}
	/* set the value of "t", which we'll use as the rbuf from here on */
	if (keep_it) {
		t = rbuf;
	} else {
		if (use_committed) {	/* if a buffer has been committed to
					 * us, use it */
			t = reconCtrlPtr->committedRbufs;
			RF_ASSERT(t);
			reconCtrlPtr->committedRbufs = t->next;
			t->next = NULL;
		} else
			if (reconCtrlPtr->floatingRbufs) {
				t = reconCtrlPtr->floatingRbufs;
				reconCtrlPtr->floatingRbufs = t->next;
				t->next = NULL;
			}
	}

	/* If we weren't able to acquire a buffer, append to the end of the
	 * buf list in the recon ctrl struct. */
	if (!t) {
		RF_ASSERT(!keep_it && !use_committed);
		Dprintf2("RECON: row %d col %d failed to acquire floating rbuf\n", rbuf->row, rbuf->col);

		raidPtr->procsInBufWait++;
		if ((raidPtr->procsInBufWait == raidPtr->numCol - 1) && (raidPtr->numFullReconBuffers == 0)) {
			printf("Buffer wait deadlock detected.  Exiting.\n");
			rf_PrintPSStatusTable(raidPtr, rbuf->row);
			RF_PANIC();
		}
		pssPtr->flags |= RF_PSS_BUFFERWAIT;
		cb = rf_AllocCallbackDesc();	/* append to buf wait list in
						 * recon ctrl structure */
		cb->row = rbuf->row;
		cb->col = rbuf->col;
		cb->callbackArg.v = rbuf->parityStripeID;
		cb->callbackArg2.v = rbuf->which_ru;
		cb->next = NULL;
		if (!reconCtrlPtr->bufferWaitList)
			reconCtrlPtr->bufferWaitList = cb;
		else {		/* might want to maintain head/tail pointers
				 * here rather than search for end of list */
			for (p = reconCtrlPtr->bufferWaitList; p->next; p = p->next);
			p->next = cb;
		}
		retcode = 1;
		goto out;
	}
	Dprintf2("RECON: row %d col %d acquired rbuf\n", rbuf->row, rbuf->col);
	RF_ETIMER_STOP(raidPtr->recon_tracerecs[rbuf->col].recon_timer);
	RF_ETIMER_EVAL(raidPtr->recon_tracerecs[rbuf->col].recon_timer);
	raidPtr->recon_tracerecs[rbuf->col].specific.recon.recon_return_to_submit_us +=
	    RF_ETIMER_VAL_US(raidPtr->recon_tracerecs[rbuf->col].recon_timer);
	RF_ETIMER_START(raidPtr->recon_tracerecs[rbuf->col].recon_timer);

	rf_LogTraceRec(raidPtr, &raidPtr->recon_tracerecs[rbuf->col]);

	/* initialize the buffer */
	if (t != rbuf) {
		t->row = rbuf->row;
		t->col = reconCtrlPtr->fcol;
		t->parityStripeID = rbuf->parityStripeID;
		t->which_ru = rbuf->which_ru;
		t->failedDiskSectorOffset = rbuf->failedDiskSectorOffset;
		t->spRow = rbuf->spRow;
		t->spCol = rbuf->spCol;
		t->spOffset = rbuf->spOffset;

		ta = t->buffer;
		t->buffer = rbuf->buffer;
		rbuf->buffer = ta;	/* swap buffers */
	}
	/* the first installation always gets installed as the destination
	 * buffer. subsequent installations get stacked up to allow for
	 * multi-way XOR */
	if (!pssPtr->rbuf) {
		pssPtr->rbuf = t;
		t->count = 1;
	} else
		pssPtr->rbufsForXor[pssPtr->xorBufCount++] = t;	/* install this buffer */

	rf_CheckForFullRbuf(raidPtr, reconCtrlPtr, pssPtr, layoutPtr->numDataCol);	/* the buffer is full if
											 * G=2 */

out:
	RF_UNLOCK_PSS_MUTEX(raidPtr, rbuf->row, rbuf->parityStripeID);
	RF_UNLOCK_MUTEX(reconCtrlPtr->rb_mutex);
	return (retcode);
}

int 
rf_MultiWayReconXor(raidPtr, pssPtr)
	RF_Raid_t *raidPtr;
	RF_ReconParityStripeStatus_t *pssPtr;	/* the pss descriptor for this
						 * parity stripe */
{
	int     i, numBufs = pssPtr->xorBufCount;
	int     numBytes = rf_RaidAddressToByte(raidPtr, raidPtr->Layout.sectorsPerStripeUnit * raidPtr->Layout.SUsPerRU);
	RF_ReconBuffer_t **rbufs = (RF_ReconBuffer_t **) pssPtr->rbufsForXor;
	RF_ReconBuffer_t *targetRbuf = (RF_ReconBuffer_t *) pssPtr->rbuf;

	RF_ASSERT(pssPtr->rbuf != NULL);
	RF_ASSERT(numBufs > 0 && numBufs < RF_PS_MAX_BUFS);
#ifdef _KERNEL
#ifndef __NetBSD__
	thread_block();		/* yield the processor before doing a big XOR */
#endif
#endif				/* _KERNEL */
	/*
         * XXX
         *
         * What if more than 9 bufs?
         */
	nWayXorFuncs[numBufs] (pssPtr->rbufsForXor, targetRbuf, numBytes / sizeof(long));

	/* release all the reconstruction buffers except the last one, which
	 * belongs to the disk whose submission caused this XOR to take place */
	for (i = 0; i < numBufs - 1; i++) {
		if (rbufs[i]->type == RF_RBUF_TYPE_FLOATING)
			rf_ReleaseFloatingReconBuffer(raidPtr, rbufs[i]->row, rbufs[i]);
		else
			if (rbufs[i]->type == RF_RBUF_TYPE_FORCED)
				rf_FreeReconBuffer(rbufs[i]);
			else
				RF_ASSERT(0);
	}
	targetRbuf->count += pssPtr->xorBufCount;
	pssPtr->xorBufCount = 0;
	return (0);
}
/* removes one full buffer from one of the full-buffer lists and returns it.
 *
 * ASSUMES THE RB_MUTEX IS UNLOCKED AT ENTRY.
 */
RF_ReconBuffer_t *
rf_GetFullReconBuffer(reconCtrlPtr)
	RF_ReconCtrl_t *reconCtrlPtr;
{
	RF_ReconBuffer_t *p;

	RF_LOCK_MUTEX(reconCtrlPtr->rb_mutex);

	if ((p = reconCtrlPtr->priorityList) != NULL) {
		reconCtrlPtr->priorityList = p->next;
		p->next = NULL;
		goto out;
	}
	if ((p = reconCtrlPtr->fullBufferList) != NULL) {
		reconCtrlPtr->fullBufferList = p->next;
		p->next = NULL;
		goto out;
	}
out:
	RF_UNLOCK_MUTEX(reconCtrlPtr->rb_mutex);
	return (p);
}


/* if the reconstruction buffer is full, move it to the full list,
 * which is maintained sorted by failed disk sector offset
 *
 * ASSUMES THE RB_MUTEX IS LOCKED AT ENTRY.  */
int 
rf_CheckForFullRbuf(raidPtr, reconCtrl, pssPtr, numDataCol)
	RF_Raid_t *raidPtr;
	RF_ReconCtrl_t *reconCtrl;
	RF_ReconParityStripeStatus_t *pssPtr;
	int     numDataCol;
{
	RF_ReconBuffer_t *p, *pt, *rbuf = (RF_ReconBuffer_t *) pssPtr->rbuf;

	if (rbuf->count == numDataCol) {
		raidPtr->numFullReconBuffers++;
		Dprintf2("RECON: rbuf for psid %ld ru %d has filled\n",
		    (long) rbuf->parityStripeID, rbuf->which_ru);
		if (!reconCtrl->fullBufferList || (rbuf->failedDiskSectorOffset < reconCtrl->fullBufferList->failedDiskSectorOffset)) {
			Dprintf2("RECON: rbuf for psid %ld ru %d is head of list\n",
			    (long) rbuf->parityStripeID, rbuf->which_ru);
			rbuf->next = reconCtrl->fullBufferList;
			reconCtrl->fullBufferList = rbuf;
		} else {
			for (pt = reconCtrl->fullBufferList, p = pt->next; p && p->failedDiskSectorOffset < rbuf->failedDiskSectorOffset; pt = p, p = p->next);
			rbuf->next = p;
			pt->next = rbuf;
			Dprintf2("RECON: rbuf for psid %ld ru %d is in list\n",
			    (long) rbuf->parityStripeID, rbuf->which_ru);
		}
#if 0
		pssPtr->writeRbuf = pssPtr->rbuf;	/* DEBUG ONLY:  we like
							 * to be able to find
							 * this rbuf while it's
							 * awaiting write */
#else
		rbuf->pssPtr = pssPtr;
#endif
		pssPtr->rbuf = NULL;
		rf_CauseReconEvent(raidPtr, rbuf->row, rbuf->col, NULL, RF_REVENT_BUFREADY);
	}
	return (0);
}


/* release a floating recon buffer for someone else to use.
 * assumes the rb_mutex is LOCKED at entry
 */
void 
rf_ReleaseFloatingReconBuffer(raidPtr, row, rbuf)
	RF_Raid_t *raidPtr;
	RF_RowCol_t row;
	RF_ReconBuffer_t *rbuf;
{
	RF_ReconCtrl_t *rcPtr = raidPtr->reconControl[row];
	RF_CallbackDesc_t *cb;

	Dprintf2("RECON: releasing rbuf for psid %ld ru %d\n",
	    (long) rbuf->parityStripeID, rbuf->which_ru);

	/* if anyone is waiting on buffers, wake one of them up.  They will
	 * subsequently wake up anyone else waiting on their RU */
	if (rcPtr->bufferWaitList) {
		rbuf->next = rcPtr->committedRbufs;
		rcPtr->committedRbufs = rbuf;
		cb = rcPtr->bufferWaitList;
		rcPtr->bufferWaitList = cb->next;
		rf_CauseReconEvent(raidPtr, cb->row, cb->col, (void *) 1, RF_REVENT_BUFCLEAR);	/* arg==1 => we've
												 * committed a buffer */
		rf_FreeCallbackDesc(cb);
		raidPtr->procsInBufWait--;
	} else {
		rbuf->next = rcPtr->floatingRbufs;
		rcPtr->floatingRbufs = rbuf;
	}
}
/* release any disk that is waiting on a buffer for the indicated RU.
 * assumes the rb_mutex is LOCKED at entry
 */
void 
rf_ReleaseBufferWaiters(raidPtr, pssPtr)
	RF_Raid_t *raidPtr;
	RF_ReconParityStripeStatus_t *pssPtr;
{
	RF_CallbackDesc_t *cb1, *cb = pssPtr->bufWaitList;

	Dprintf2("RECON: releasing buf waiters for psid %ld ru %d\n",
	    (long) pssPtr->parityStripeID, pssPtr->which_ru);
	pssPtr->flags &= ~RF_PSS_BUFFERWAIT;
	while (cb) {
		cb1 = cb->next;
		cb->next = NULL;
		rf_CauseReconEvent(raidPtr, cb->row, cb->col, (void *) 0, RF_REVENT_BUFCLEAR);	/* arg==0 => we haven't
												 * committed a buffer */
		rf_FreeCallbackDesc(cb);
		cb = cb1;
	}
	pssPtr->bufWaitList = NULL;
}
/* when reconstruction is forced on an RU, there may be some disks waiting to
 * acquire a buffer for that RU.  Since we allocate a new buffer as part of
 * the forced-reconstruction process, we no longer have to wait for any
 * buffers, so we wakeup any waiter that we find in the bufferWaitList
 *
 * assumes the rb_mutex is LOCKED at entry
 */
void 
rf_ReleaseBufferWaiter(rcPtr, rbuf)
	RF_ReconCtrl_t *rcPtr;
	RF_ReconBuffer_t *rbuf;
{
	RF_CallbackDesc_t *cb, *cbt;

	for (cbt = NULL, cb = rcPtr->bufferWaitList; cb; cbt = cb, cb = cb->next) {
		if ((cb->callbackArg.v == rbuf->parityStripeID) && (cb->callbackArg2.v == rbuf->which_ru)) {
			Dprintf2("RECON: Dropping row %d col %d from buffer wait list\n", cb->row, cb->col);
			if (cbt)
				cbt->next = cb->next;
			else
				rcPtr->bufferWaitList = cb->next;
			rf_CauseReconEvent((RF_Raid_t *) rbuf->raidPtr, cb->row, cb->col, (void *) 0, RF_REVENT_BUFREADY);	/* arg==0 => no
																 * committed buffer */
			rf_FreeCallbackDesc(cb);
			return;
		}
	}
}