1 /* 2 * Copyright (c) 2015-2018 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@dragonflybsd.org> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 /* 35 * This module implements the hammer2 helper thread API, including 36 * the frontend/backend XOP API. 37 */ 38 #include "hammer2.h" 39 40 #define H2XOPDESCRIPTOR(label) \ 41 hammer2_xop_desc_t hammer2_##label##_desc = { \ 42 .storage_func = hammer2_xop_##label, \ 43 .id = #label \ 44 }; \ 45 46 H2XOPDESCRIPTOR(ipcluster); 47 H2XOPDESCRIPTOR(readdir); 48 H2XOPDESCRIPTOR(nresolve); 49 H2XOPDESCRIPTOR(unlink); 50 H2XOPDESCRIPTOR(nrename); 51 H2XOPDESCRIPTOR(scanlhc); 52 H2XOPDESCRIPTOR(scanall); 53 H2XOPDESCRIPTOR(lookup); 54 H2XOPDESCRIPTOR(delete); 55 H2XOPDESCRIPTOR(inode_mkdirent); 56 H2XOPDESCRIPTOR(inode_create); 57 H2XOPDESCRIPTOR(inode_create_det); 58 H2XOPDESCRIPTOR(inode_create_ins); 59 H2XOPDESCRIPTOR(inode_destroy); 60 H2XOPDESCRIPTOR(inode_chain_sync); 61 H2XOPDESCRIPTOR(inode_unlinkall); 62 H2XOPDESCRIPTOR(inode_connect); 63 H2XOPDESCRIPTOR(inode_flush); 64 H2XOPDESCRIPTOR(strategy_read); 65 H2XOPDESCRIPTOR(strategy_write); 66 67 /* 68 * Set flags and wakeup any waiters. 69 * 70 * WARNING! During teardown (thr) can disappear the instant our cmpset 71 * succeeds. 72 */ 73 void 74 hammer2_thr_signal(hammer2_thread_t *thr, uint32_t flags) 75 { 76 uint32_t oflags; 77 uint32_t nflags; 78 79 for (;;) { 80 oflags = thr->flags; 81 cpu_ccfence(); 82 nflags = (oflags | flags) & ~HAMMER2_THREAD_WAITING; 83 84 if (oflags & HAMMER2_THREAD_WAITING) { 85 if (atomic_cmpset_int(&thr->flags, oflags, nflags)) { 86 wakeup(&thr->flags); 87 break; 88 } 89 } else { 90 if (atomic_cmpset_int(&thr->flags, oflags, nflags)) 91 break; 92 } 93 } 94 } 95 96 /* 97 * Set and clear flags and wakeup any waiters. 98 * 99 * WARNING! During teardown (thr) can disappear the instant our cmpset 100 * succeeds. 101 */ 102 void 103 hammer2_thr_signal2(hammer2_thread_t *thr, uint32_t posflags, uint32_t negflags) 104 { 105 uint32_t oflags; 106 uint32_t nflags; 107 108 for (;;) { 109 oflags = thr->flags; 110 cpu_ccfence(); 111 nflags = (oflags | posflags) & 112 ~(negflags | HAMMER2_THREAD_WAITING); 113 if (oflags & HAMMER2_THREAD_WAITING) { 114 if (atomic_cmpset_int(&thr->flags, oflags, nflags)) { 115 wakeup(&thr->flags); 116 break; 117 } 118 } else { 119 if (atomic_cmpset_int(&thr->flags, oflags, nflags)) 120 break; 121 } 122 } 123 } 124 125 /* 126 * Wait until all the bits in flags are set. 127 * 128 * WARNING! During teardown (thr) can disappear the instant our cmpset 129 * succeeds. 130 */ 131 void 132 hammer2_thr_wait(hammer2_thread_t *thr, uint32_t flags) 133 { 134 uint32_t oflags; 135 uint32_t nflags; 136 137 for (;;) { 138 oflags = thr->flags; 139 cpu_ccfence(); 140 if ((oflags & flags) == flags) 141 break; 142 nflags = oflags | HAMMER2_THREAD_WAITING; 143 tsleep_interlock(&thr->flags, 0); 144 if (atomic_cmpset_int(&thr->flags, oflags, nflags)) { 145 tsleep(&thr->flags, PINTERLOCKED, "h2twait", hz*60); 146 } 147 } 148 } 149 150 /* 151 * Wait until any of the bits in flags are set, with timeout. 152 * 153 * WARNING! During teardown (thr) can disappear the instant our cmpset 154 * succeeds. 155 */ 156 int 157 hammer2_thr_wait_any(hammer2_thread_t *thr, uint32_t flags, int timo) 158 { 159 uint32_t oflags; 160 uint32_t nflags; 161 int error; 162 163 error = 0; 164 for (;;) { 165 oflags = thr->flags; 166 cpu_ccfence(); 167 if (oflags & flags) 168 break; 169 nflags = oflags | HAMMER2_THREAD_WAITING; 170 tsleep_interlock(&thr->flags, 0); 171 if (atomic_cmpset_int(&thr->flags, oflags, nflags)) { 172 error = tsleep(&thr->flags, PINTERLOCKED, 173 "h2twait", timo); 174 } 175 if (error == ETIMEDOUT) { 176 error = HAMMER2_ERROR_ETIMEDOUT; 177 break; 178 } 179 } 180 return error; 181 } 182 183 /* 184 * Wait until the bits in flags are clear. 185 * 186 * WARNING! During teardown (thr) can disappear the instant our cmpset 187 * succeeds. 188 */ 189 void 190 hammer2_thr_wait_neg(hammer2_thread_t *thr, uint32_t flags) 191 { 192 uint32_t oflags; 193 uint32_t nflags; 194 195 for (;;) { 196 oflags = thr->flags; 197 cpu_ccfence(); 198 if ((oflags & flags) == 0) 199 break; 200 nflags = oflags | HAMMER2_THREAD_WAITING; 201 tsleep_interlock(&thr->flags, 0); 202 if (atomic_cmpset_int(&thr->flags, oflags, nflags)) { 203 tsleep(&thr->flags, PINTERLOCKED, "h2twait", hz*60); 204 } 205 } 206 } 207 208 /* 209 * Initialize the supplied thread structure, starting the specified 210 * thread. 211 * 212 * NOTE: thr structure can be retained across mounts and unmounts for this 213 * pmp, so make sure the flags are in a sane state. 214 */ 215 void 216 hammer2_thr_create(hammer2_thread_t *thr, hammer2_pfs_t *pmp, 217 hammer2_dev_t *hmp, 218 const char *id, int clindex, int repidx, 219 void (*func)(void *arg)) 220 { 221 thr->pmp = pmp; /* xop helpers */ 222 thr->hmp = hmp; /* bulkfree */ 223 thr->clindex = clindex; 224 thr->repidx = repidx; 225 TAILQ_INIT(&thr->xopq); 226 atomic_clear_int(&thr->flags, HAMMER2_THREAD_STOP | 227 HAMMER2_THREAD_STOPPED | 228 HAMMER2_THREAD_FREEZE | 229 HAMMER2_THREAD_FROZEN); 230 if (thr->scratch == NULL) 231 thr->scratch = kmalloc(MAXPHYS, M_HAMMER2, M_WAITOK | M_ZERO); 232 if (repidx >= 0) { 233 lwkt_create(func, thr, &thr->td, NULL, 0, repidx % ncpus, 234 "%s-%s.%02d", id, pmp->pfs_names[clindex], repidx); 235 } else if (pmp) { 236 lwkt_create(func, thr, &thr->td, NULL, 0, -1, 237 "%s-%s", id, pmp->pfs_names[clindex]); 238 } else { 239 lwkt_create(func, thr, &thr->td, NULL, 0, -1, "%s", id); 240 } 241 } 242 243 /* 244 * Terminate a thread. This function will silently return if the thread 245 * was never initialized or has already been deleted. 246 * 247 * This is accomplished by setting the STOP flag and waiting for the td 248 * structure to become NULL. 249 */ 250 void 251 hammer2_thr_delete(hammer2_thread_t *thr) 252 { 253 if (thr->td == NULL) 254 return; 255 hammer2_thr_signal(thr, HAMMER2_THREAD_STOP); 256 hammer2_thr_wait(thr, HAMMER2_THREAD_STOPPED); 257 thr->pmp = NULL; 258 if (thr->scratch) { 259 kfree(thr->scratch, M_HAMMER2); 260 thr->scratch = NULL; 261 } 262 KKASSERT(TAILQ_EMPTY(&thr->xopq)); 263 } 264 265 /* 266 * Asynchronous remaster request. Ask the synchronization thread to 267 * start over soon (as if it were frozen and unfrozen, but without waiting). 268 * The thread always recalculates mastership relationships when restarting. 269 */ 270 void 271 hammer2_thr_remaster(hammer2_thread_t *thr) 272 { 273 if (thr->td == NULL) 274 return; 275 hammer2_thr_signal(thr, HAMMER2_THREAD_REMASTER); 276 } 277 278 void 279 hammer2_thr_freeze_async(hammer2_thread_t *thr) 280 { 281 hammer2_thr_signal(thr, HAMMER2_THREAD_FREEZE); 282 } 283 284 void 285 hammer2_thr_freeze(hammer2_thread_t *thr) 286 { 287 if (thr->td == NULL) 288 return; 289 hammer2_thr_signal(thr, HAMMER2_THREAD_FREEZE); 290 hammer2_thr_wait(thr, HAMMER2_THREAD_FROZEN); 291 } 292 293 void 294 hammer2_thr_unfreeze(hammer2_thread_t *thr) 295 { 296 if (thr->td == NULL) 297 return; 298 hammer2_thr_signal(thr, HAMMER2_THREAD_UNFREEZE); 299 hammer2_thr_wait_neg(thr, HAMMER2_THREAD_FROZEN); 300 } 301 302 int 303 hammer2_thr_break(hammer2_thread_t *thr) 304 { 305 if (thr->flags & (HAMMER2_THREAD_STOP | 306 HAMMER2_THREAD_REMASTER | 307 HAMMER2_THREAD_FREEZE)) { 308 return 1; 309 } 310 return 0; 311 } 312 313 /**************************************************************************** 314 * HAMMER2 XOPS API * 315 ****************************************************************************/ 316 317 void 318 hammer2_xop_group_init(hammer2_pfs_t *pmp, hammer2_xop_group_t *xgrp) 319 { 320 /* no extra fields in structure at the moment */ 321 } 322 323 /* 324 * Allocate a XOP request. 325 * 326 * Once allocated a XOP request can be started, collected, and retired, 327 * and can be retired early if desired. 328 * 329 * NOTE: Fifo indices might not be zero but ri == wi on objcache_get(). 330 */ 331 void * 332 hammer2_xop_alloc(hammer2_inode_t *ip, int flags) 333 { 334 hammer2_xop_t *xop; 335 336 xop = objcache_get(cache_xops, M_WAITOK); 337 KKASSERT(xop->head.cluster.array[0].chain == NULL); 338 339 xop->head.ip1 = ip; 340 xop->head.desc = NULL; 341 xop->head.flags = flags; 342 xop->head.state = 0; 343 xop->head.error = 0; 344 xop->head.collect_key = 0; 345 xop->head.focus_dio = NULL; 346 347 if (flags & HAMMER2_XOP_MODIFYING) 348 xop->head.mtid = hammer2_trans_sub(ip->pmp); 349 else 350 xop->head.mtid = 0; 351 352 xop->head.cluster.nchains = ip->cluster.nchains; 353 xop->head.cluster.pmp = ip->pmp; 354 xop->head.cluster.flags = HAMMER2_CLUSTER_LOCKED; 355 356 /* 357 * run_mask - Active thread (or frontend) associated with XOP 358 */ 359 xop->head.run_mask = HAMMER2_XOPMASK_VOP; 360 361 hammer2_inode_ref(ip); 362 363 return xop; 364 } 365 366 void 367 hammer2_xop_setname(hammer2_xop_head_t *xop, const char *name, size_t name_len) 368 { 369 xop->name1 = kmalloc(name_len + 1, M_HAMMER2, M_WAITOK | M_ZERO); 370 xop->name1_len = name_len; 371 bcopy(name, xop->name1, name_len); 372 } 373 374 void 375 hammer2_xop_setname2(hammer2_xop_head_t *xop, const char *name, size_t name_len) 376 { 377 xop->name2 = kmalloc(name_len + 1, M_HAMMER2, M_WAITOK | M_ZERO); 378 xop->name2_len = name_len; 379 bcopy(name, xop->name2, name_len); 380 } 381 382 size_t 383 hammer2_xop_setname_inum(hammer2_xop_head_t *xop, hammer2_key_t inum) 384 { 385 const size_t name_len = 18; 386 387 xop->name1 = kmalloc(name_len + 1, M_HAMMER2, M_WAITOK | M_ZERO); 388 xop->name1_len = name_len; 389 ksnprintf(xop->name1, name_len + 1, "0x%016jx", (intmax_t)inum); 390 391 return name_len; 392 } 393 394 395 void 396 hammer2_xop_setip2(hammer2_xop_head_t *xop, hammer2_inode_t *ip2) 397 { 398 xop->ip2 = ip2; 399 hammer2_inode_ref(ip2); 400 } 401 402 void 403 hammer2_xop_setip3(hammer2_xop_head_t *xop, hammer2_inode_t *ip3) 404 { 405 xop->ip3 = ip3; 406 hammer2_inode_ref(ip3); 407 } 408 409 void 410 hammer2_xop_reinit(hammer2_xop_head_t *xop) 411 { 412 xop->state = 0; 413 xop->error = 0; 414 xop->collect_key = 0; 415 xop->run_mask = HAMMER2_XOPMASK_VOP; 416 } 417 418 /* 419 * A mounted PFS needs Xops threads to support frontend operations. 420 */ 421 void 422 hammer2_xop_helper_create(hammer2_pfs_t *pmp) 423 { 424 int i; 425 int j; 426 427 lockmgr(&pmp->lock, LK_EXCLUSIVE); 428 pmp->has_xop_threads = 1; 429 430 for (i = 0; i < pmp->iroot->cluster.nchains; ++i) { 431 for (j = 0; j < HAMMER2_XOPGROUPS; ++j) { 432 if (pmp->xop_groups[j].thrs[i].td) 433 continue; 434 hammer2_thr_create(&pmp->xop_groups[j].thrs[i], 435 pmp, NULL, 436 "h2xop", i, j, 437 hammer2_primary_xops_thread); 438 } 439 } 440 lockmgr(&pmp->lock, LK_RELEASE); 441 } 442 443 void 444 hammer2_xop_helper_cleanup(hammer2_pfs_t *pmp) 445 { 446 int i; 447 int j; 448 449 for (i = 0; i < pmp->pfs_nmasters; ++i) { 450 for (j = 0; j < HAMMER2_XOPGROUPS; ++j) { 451 if (pmp->xop_groups[j].thrs[i].td) 452 hammer2_thr_delete(&pmp->xop_groups[j].thrs[i]); 453 } 454 } 455 pmp->has_xop_threads = 0; 456 } 457 458 /* 459 * Start a XOP request, queueing it to all nodes in the cluster to 460 * execute the cluster op. 461 * 462 * XXX optimize single-target case. 463 */ 464 void 465 hammer2_xop_start_except(hammer2_xop_head_t *xop, hammer2_xop_desc_t *desc, 466 int notidx) 467 { 468 hammer2_inode_t *ip1; 469 hammer2_pfs_t *pmp; 470 hammer2_thread_t *thr; 471 int i; 472 int ng; 473 int nchains; 474 475 ip1 = xop->ip1; 476 pmp = ip1->pmp; 477 if (pmp->has_xop_threads == 0) 478 hammer2_xop_helper_create(pmp); 479 480 /* 481 * The intent of the XOP sequencer is to ensure that ops on the same 482 * inode execute in the same order. This is necessary when issuing 483 * modifying operations to multiple targets because some targets might 484 * get behind and the frontend is allowed to complete the moment a 485 * quorum of targets succeed. 486 * 487 * Strategy operations: 488 * 489 * (1) Must be segregated from non-strategy operations to 490 * avoid a deadlock. A vfsync and a bread/bwrite can 491 * deadlock the vfsync's buffer list scan. 492 * 493 * (2) Reads are separated from writes to avoid write stalls 494 * from excessively intefering with reads. Reads are allowed 495 * to wander across multiple worker threads for potential 496 * single-file concurrency improvements. 497 * 498 * (3) Writes are serialized to a single worker thread (for any 499 * given inode) in order to try to improve block allocation 500 * sequentiality and to reduce lock contention. 501 * 502 * TODO - RENAME fails here because it is potentially modifying 503 * three different inodes, but we triple-lock the inodes 504 * involved so it shouldn't create a sequencing schism. 505 */ 506 if (xop->flags & HAMMER2_XOP_STRATEGY) { 507 hammer2_xop_strategy_t *xopst; 508 hammer2_off_t off; 509 int cdr; 510 511 xopst = &((hammer2_xop_t *)xop)->xop_strategy; 512 ng = (int)(hammer2_icrc32(&xop->ip1, sizeof(xop->ip1))); 513 if (desc == &hammer2_strategy_read_desc) { 514 off = xopst->lbase / HAMMER2_PBUFSIZE; 515 cdr = hammer2_cluster_data_read; 516 /* sysctl race, load into var */ 517 cpu_ccfence(); 518 if (cdr) 519 off /= cdr; 520 ng ^= hammer2_icrc32(&off, sizeof(off)) & 521 (hammer2_worker_rmask << 1); 522 ng |= 1; 523 } else { 524 #if 0 525 off = xopst->lbase >> 21; 526 ng ^= hammer2_icrc32(&off, sizeof(off)) & 3; 527 #endif 528 ng &= ~1; 529 } 530 ng = ng & (HAMMER2_XOPGROUPS_MASK >> 1); 531 ng += HAMMER2_XOPGROUPS / 2; 532 } else { 533 ng = (int)(hammer2_icrc32(&xop->ip1, sizeof(xop->ip1))); 534 ng = ng & (HAMMER2_XOPGROUPS_MASK >> 1); 535 } 536 xop->desc = desc; 537 538 /* 539 * The instant xop is queued another thread can pick it off. In the 540 * case of asynchronous ops, another thread might even finish and 541 * deallocate it. 542 */ 543 hammer2_spin_ex(&pmp->xop_spin); 544 nchains = ip1->cluster.nchains; 545 for (i = 0; i < nchains; ++i) { 546 /* 547 * XXX ip1->cluster.array* not stable here. This temporary 548 * hack fixes basic issues in target XOPs which need to 549 * obtain a starting chain from the inode but does not 550 * address possible races against inode updates which 551 * might NULL-out a chain. 552 */ 553 if (i != notidx && ip1->cluster.array[i].chain) { 554 thr = &pmp->xop_groups[ng].thrs[i]; 555 atomic_set_64(&xop->run_mask, 1LLU << i); 556 atomic_set_64(&xop->chk_mask, 1LLU << i); 557 xop->collect[i].thr = thr; 558 TAILQ_INSERT_TAIL(&thr->xopq, xop, collect[i].entry); 559 } 560 } 561 hammer2_spin_unex(&pmp->xop_spin); 562 /* xop can become invalid at this point */ 563 564 /* 565 * Each thread has its own xopq 566 */ 567 for (i = 0; i < nchains; ++i) { 568 if (i != notidx) { 569 thr = &pmp->xop_groups[ng].thrs[i]; 570 hammer2_thr_signal(thr, HAMMER2_THREAD_XOPQ); 571 } 572 } 573 } 574 575 void 576 hammer2_xop_start(hammer2_xop_head_t *xop, hammer2_xop_desc_t *desc) 577 { 578 hammer2_xop_start_except(xop, desc, -1); 579 } 580 581 /* 582 * Retire a XOP. Used by both the VOP frontend and by the XOP backend. 583 */ 584 void 585 hammer2_xop_retire(hammer2_xop_head_t *xop, uint64_t mask) 586 { 587 hammer2_chain_t *chain; 588 uint64_t nmask; 589 int i; 590 591 /* 592 * Remove the frontend collector or remove a backend feeder. 593 * 594 * When removing the frontend we must wakeup any backend feeders 595 * who are waiting for FIFO space. 596 * 597 * When removing the last backend feeder we must wakeup any waiting 598 * frontend. 599 */ 600 KKASSERT(xop->run_mask & mask); 601 nmask = atomic_fetchadd_64(&xop->run_mask, 602 -mask + HAMMER2_XOPMASK_FEED); 603 604 /* 605 * More than one entity left 606 */ 607 if ((nmask & HAMMER2_XOPMASK_ALLDONE) != mask) { 608 /* 609 * Frontend terminating, wakeup any backends waiting on 610 * fifo full. 611 * 612 * NOTE!!! The xop can get ripped out from under us at 613 * this point, so do not reference it again. 614 * The wakeup(xop) doesn't touch the xop and 615 * is ok. 616 */ 617 if (mask == HAMMER2_XOPMASK_VOP) { 618 if (nmask & HAMMER2_XOPMASK_FIFOW) 619 wakeup(xop); 620 } 621 622 /* 623 * Wakeup frontend if the last backend is terminating. 624 */ 625 nmask -= mask; 626 if ((nmask & HAMMER2_XOPMASK_ALLDONE) == HAMMER2_XOPMASK_VOP) { 627 if (nmask & HAMMER2_XOPMASK_WAIT) 628 wakeup(xop); 629 } 630 631 return; 632 } 633 /* else nobody else left, we can ignore FIFOW */ 634 635 /* 636 * All collectors are gone, we can cleanup and dispose of the XOP. 637 * Note that this can wind up being a frontend OR a backend. 638 * Pending chains are locked shared and not owned by any thread. 639 * 640 * Cleanup the collection cluster. 641 */ 642 for (i = 0; i < xop->cluster.nchains; ++i) { 643 xop->cluster.array[i].flags = 0; 644 chain = xop->cluster.array[i].chain; 645 if (chain) { 646 xop->cluster.array[i].chain = NULL; 647 hammer2_chain_drop_unhold(chain); 648 } 649 } 650 651 /* 652 * Cleanup the fifos. Since we are the only entity left on this 653 * xop we don't have to worry about fifo flow control, and one 654 * lfence() will do the job. 655 */ 656 cpu_lfence(); 657 mask = xop->chk_mask; 658 for (i = 0; mask && i < HAMMER2_MAXCLUSTER; ++i) { 659 hammer2_xop_fifo_t *fifo = &xop->collect[i]; 660 while (fifo->ri != fifo->wi) { 661 chain = fifo->array[fifo->ri & HAMMER2_XOPFIFO_MASK]; 662 if (chain) 663 hammer2_chain_drop_unhold(chain); 664 ++fifo->ri; 665 } 666 mask &= ~(1U << i); 667 } 668 669 /* 670 * The inode is only held at this point, simply drop it. 671 */ 672 if (xop->ip1) { 673 hammer2_inode_drop(xop->ip1); 674 xop->ip1 = NULL; 675 } 676 if (xop->ip2) { 677 hammer2_inode_drop(xop->ip2); 678 xop->ip2 = NULL; 679 } 680 if (xop->ip3) { 681 hammer2_inode_drop(xop->ip3); 682 xop->ip3 = NULL; 683 } 684 if (xop->name1) { 685 kfree(xop->name1, M_HAMMER2); 686 xop->name1 = NULL; 687 xop->name1_len = 0; 688 } 689 if (xop->name2) { 690 kfree(xop->name2, M_HAMMER2); 691 xop->name2 = NULL; 692 xop->name2_len = 0; 693 } 694 695 objcache_put(cache_xops, xop); 696 } 697 698 /* 699 * (Backend) Returns non-zero if the frontend is still attached. 700 */ 701 int 702 hammer2_xop_active(hammer2_xop_head_t *xop) 703 { 704 if (xop->run_mask & HAMMER2_XOPMASK_VOP) 705 return 1; 706 else 707 return 0; 708 } 709 710 /* 711 * (Backend) Feed chain data through the cluster validator and back to 712 * the frontend. Chains are fed from multiple nodes concurrently 713 * and pipelined via per-node FIFOs in the XOP. 714 * 715 * The chain must be locked (either shared or exclusive). The caller may 716 * unlock and drop the chain on return. This function will add an extra 717 * ref and hold the chain's data for the pass-back. 718 * 719 * No xop lock is needed because we are only manipulating fields under 720 * our direct control. 721 * 722 * Returns 0 on success and a hammer2 error code if sync is permanently 723 * lost. The caller retains a ref on the chain but by convention 724 * the lock is typically inherited by the xop (caller loses lock). 725 * 726 * Returns non-zero on error. In this situation the caller retains a 727 * ref on the chain but loses the lock (we unlock here). 728 */ 729 int 730 hammer2_xop_feed(hammer2_xop_head_t *xop, hammer2_chain_t *chain, 731 int clindex, int error) 732 { 733 hammer2_xop_fifo_t *fifo; 734 uint64_t mask; 735 736 /* 737 * Early termination (typicaly of xop_readir) 738 */ 739 if (hammer2_xop_active(xop) == 0) { 740 error = HAMMER2_ERROR_ABORTED; 741 goto done; 742 } 743 744 /* 745 * Multi-threaded entry into the XOP collector. We own the 746 * fifo->wi for our clindex. 747 */ 748 fifo = &xop->collect[clindex]; 749 750 if (fifo->ri == fifo->wi - HAMMER2_XOPFIFO) 751 lwkt_yield(); 752 while (fifo->ri == fifo->wi - HAMMER2_XOPFIFO) { 753 atomic_set_int(&fifo->flags, HAMMER2_XOP_FIFO_STALL); 754 mask = xop->run_mask; 755 if ((mask & HAMMER2_XOPMASK_VOP) == 0) { 756 error = HAMMER2_ERROR_ABORTED; 757 goto done; 758 } 759 tsleep_interlock(xop, 0); 760 if (atomic_cmpset_64(&xop->run_mask, mask, 761 mask | HAMMER2_XOPMASK_FIFOW)) { 762 if (fifo->ri == fifo->wi - HAMMER2_XOPFIFO) { 763 tsleep(xop, PINTERLOCKED, "h2feed", hz*60); 764 } 765 } 766 /* retry */ 767 } 768 atomic_clear_int(&fifo->flags, HAMMER2_XOP_FIFO_STALL); 769 if (chain) 770 hammer2_chain_ref_hold(chain); 771 if (error == 0 && chain) 772 error = chain->error; 773 fifo->errors[fifo->wi & HAMMER2_XOPFIFO_MASK] = error; 774 fifo->array[fifo->wi & HAMMER2_XOPFIFO_MASK] = chain; 775 cpu_sfence(); 776 ++fifo->wi; 777 778 mask = atomic_fetchadd_64(&xop->run_mask, HAMMER2_XOPMASK_FEED); 779 if (mask & HAMMER2_XOPMASK_WAIT) { 780 atomic_clear_64(&xop->run_mask, HAMMER2_XOPMASK_WAIT); 781 wakeup(xop); 782 } 783 error = 0; 784 785 /* 786 * Cleanup. If an error occurred we eat the lock. If no error 787 * occurred the fifo inherits the lock and gains an additional ref. 788 * 789 * The caller's ref remains in both cases. 790 */ 791 done: 792 return error; 793 } 794 795 /* 796 * (Frontend) collect a response from a running cluster op. 797 * 798 * Responses are fed from all appropriate nodes concurrently 799 * and collected into a cohesive response >= collect_key. 800 * 801 * The collector will return the instant quorum or other requirements 802 * are met, even if some nodes get behind or become non-responsive. 803 * 804 * HAMMER2_XOP_COLLECT_NOWAIT - Used to 'poll' a completed collection, 805 * usually called synchronously from the 806 * node XOPs for the strategy code to 807 * fake the frontend collection and complete 808 * the BIO as soon as possible. 809 * 810 * HAMMER2_XOP_SYNCHRONIZER - Reqeuest synchronization with a particular 811 * cluster index, prevents looping when that 812 * index is out of sync so caller can act on 813 * the out of sync element. ESRCH and EDEADLK 814 * can be returned if this flag is specified. 815 * 816 * Returns 0 on success plus a filled out xop->cluster structure. 817 * Return ENOENT on normal termination. 818 * Otherwise return an error. 819 * 820 * WARNING! If the xop returns a cluster with a non-NULL focus, note that 821 * none of the chains in the cluster (or the focus) are either 822 * locked or I/O synchronized with the cpu. hammer2_xop_gdata() 823 * and hammer2_xop_pdata() must be used to safely access the focus 824 * chain's content. 825 * 826 * The frontend can make certain assumptions based on higher-level 827 * locking done by the frontend, but data integrity absolutely 828 * requires using the gdata/pdata API. 829 */ 830 int 831 hammer2_xop_collect(hammer2_xop_head_t *xop, int flags) 832 { 833 hammer2_xop_fifo_t *fifo; 834 hammer2_chain_t *chain; 835 hammer2_key_t lokey; 836 uint64_t mask; 837 int error; 838 int keynull; 839 int adv; /* advance the element */ 840 int i; 841 842 loop: 843 /* 844 * First loop tries to advance pieces of the cluster which 845 * are out of sync. 846 */ 847 lokey = HAMMER2_KEY_MAX; 848 keynull = HAMMER2_CHECK_NULL; 849 mask = xop->run_mask; 850 cpu_lfence(); 851 852 for (i = 0; i < xop->cluster.nchains; ++i) { 853 chain = xop->cluster.array[i].chain; 854 if (chain == NULL) { 855 adv = 1; 856 } else if (chain->bref.key < xop->collect_key) { 857 adv = 1; 858 } else { 859 keynull &= ~HAMMER2_CHECK_NULL; 860 if (lokey > chain->bref.key) 861 lokey = chain->bref.key; 862 adv = 0; 863 } 864 if (adv == 0) 865 continue; 866 867 /* 868 * Advance element if possible, advanced element may be NULL. 869 */ 870 if (chain) 871 hammer2_chain_drop_unhold(chain); 872 873 fifo = &xop->collect[i]; 874 if (fifo->ri != fifo->wi) { 875 cpu_lfence(); 876 chain = fifo->array[fifo->ri & HAMMER2_XOPFIFO_MASK]; 877 error = fifo->errors[fifo->ri & HAMMER2_XOPFIFO_MASK]; 878 ++fifo->ri; 879 xop->cluster.array[i].chain = chain; 880 xop->cluster.array[i].error = error; 881 if (chain == NULL) { 882 /* XXX */ 883 xop->cluster.array[i].flags |= 884 HAMMER2_CITEM_NULL; 885 } 886 if (fifo->wi - fifo->ri <= HAMMER2_XOPFIFO / 2) { 887 if (fifo->flags & HAMMER2_XOP_FIFO_STALL) { 888 atomic_clear_int(&fifo->flags, 889 HAMMER2_XOP_FIFO_STALL); 890 wakeup(xop); 891 lwkt_yield(); 892 } 893 } 894 --i; /* loop on same index */ 895 } else { 896 /* 897 * Retain CITEM_NULL flag. If set just repeat EOF. 898 * If not, the NULL,0 combination indicates an 899 * operation in-progress. 900 */ 901 xop->cluster.array[i].chain = NULL; 902 /* retain any CITEM_NULL setting */ 903 } 904 } 905 906 /* 907 * Determine whether the lowest collected key meets clustering 908 * requirements. Returns: 909 * 910 * 0 - key valid, cluster can be returned. 911 * 912 * ENOENT - normal end of scan, return ENOENT. 913 * 914 * ESRCH - sufficient elements collected, quorum agreement 915 * that lokey is not a valid element and should be 916 * skipped. 917 * 918 * EDEADLK - sufficient elements collected, no quorum agreement 919 * (and no agreement possible). In this situation a 920 * repair is needed, for now we loop. 921 * 922 * EINPROGRESS - insufficient elements collected to resolve, wait 923 * for event and loop. 924 */ 925 if ((flags & HAMMER2_XOP_COLLECT_WAITALL) && 926 (mask & HAMMER2_XOPMASK_ALLDONE) != HAMMER2_XOPMASK_VOP) { 927 error = HAMMER2_ERROR_EINPROGRESS; 928 } else { 929 error = hammer2_cluster_check(&xop->cluster, lokey, keynull); 930 } 931 if (error == HAMMER2_ERROR_EINPROGRESS) { 932 if (flags & HAMMER2_XOP_COLLECT_NOWAIT) 933 goto done; 934 tsleep_interlock(xop, 0); 935 if (atomic_cmpset_64(&xop->run_mask, 936 mask, mask | HAMMER2_XOPMASK_WAIT)) { 937 tsleep(xop, PINTERLOCKED, "h2coll", hz*60); 938 } 939 goto loop; 940 } 941 if (error == HAMMER2_ERROR_ESRCH) { 942 if (lokey != HAMMER2_KEY_MAX) { 943 xop->collect_key = lokey + 1; 944 goto loop; 945 } 946 error = HAMMER2_ERROR_ENOENT; 947 } 948 if (error == HAMMER2_ERROR_EDEADLK) { 949 kprintf("hammer2: no quorum possible lokey %016jx\n", 950 lokey); 951 if (lokey != HAMMER2_KEY_MAX) { 952 xop->collect_key = lokey + 1; 953 goto loop; 954 } 955 error = HAMMER2_ERROR_ENOENT; 956 } 957 if (lokey == HAMMER2_KEY_MAX) 958 xop->collect_key = lokey; 959 else 960 xop->collect_key = lokey + 1; 961 done: 962 return error; 963 } 964 965 /* 966 * N x M processing threads are available to handle XOPs, N per cluster 967 * index x M cluster nodes. 968 * 969 * Locate and return the next runnable xop, or NULL if no xops are 970 * present or none of the xops are currently runnable (for various reasons). 971 * The xop is left on the queue and serves to block other dependent xops 972 * from being run. 973 * 974 * Dependent xops will not be returned. 975 * 976 * Sets HAMMER2_XOP_FIFO_RUN on the returned xop or returns NULL. 977 * 978 * NOTE! Xops run concurrently for each cluster index. 979 */ 980 #define XOP_HASH_SIZE 16 981 #define XOP_HASH_MASK (XOP_HASH_SIZE - 1) 982 983 static __inline 984 int 985 xop_testhash(hammer2_thread_t *thr, hammer2_inode_t *ip, uint32_t *hash) 986 { 987 uint32_t mask; 988 int hv; 989 990 hv = (int)((uintptr_t)ip + (uintptr_t)thr) / sizeof(hammer2_inode_t); 991 mask = 1U << (hv & 31); 992 hv >>= 5; 993 994 return ((int)(hash[hv & XOP_HASH_MASK] & mask)); 995 } 996 997 static __inline 998 void 999 xop_sethash(hammer2_thread_t *thr, hammer2_inode_t *ip, uint32_t *hash) 1000 { 1001 uint32_t mask; 1002 int hv; 1003 1004 hv = (int)((uintptr_t)ip + (uintptr_t)thr) / sizeof(hammer2_inode_t); 1005 mask = 1U << (hv & 31); 1006 hv >>= 5; 1007 1008 hash[hv & XOP_HASH_MASK] |= mask; 1009 } 1010 1011 static 1012 hammer2_xop_head_t * 1013 hammer2_xop_next(hammer2_thread_t *thr) 1014 { 1015 hammer2_pfs_t *pmp = thr->pmp; 1016 int clindex = thr->clindex; 1017 uint32_t hash[XOP_HASH_SIZE] = { 0 }; 1018 hammer2_xop_head_t *xop; 1019 1020 hammer2_spin_ex(&pmp->xop_spin); 1021 TAILQ_FOREACH(xop, &thr->xopq, collect[clindex].entry) { 1022 /* 1023 * Check dependency 1024 */ 1025 if (xop_testhash(thr, xop->ip1, hash) || 1026 (xop->ip2 && xop_testhash(thr, xop->ip2, hash)) || 1027 (xop->ip3 && xop_testhash(thr, xop->ip3, hash))) { 1028 continue; 1029 } 1030 xop_sethash(thr, xop->ip1, hash); 1031 if (xop->ip2) 1032 xop_sethash(thr, xop->ip2, hash); 1033 if (xop->ip3) 1034 xop_sethash(thr, xop->ip3, hash); 1035 1036 /* 1037 * Check already running 1038 */ 1039 if (xop->collect[clindex].flags & HAMMER2_XOP_FIFO_RUN) 1040 continue; 1041 1042 /* 1043 * Found a good one, return it. 1044 */ 1045 atomic_set_int(&xop->collect[clindex].flags, 1046 HAMMER2_XOP_FIFO_RUN); 1047 break; 1048 } 1049 hammer2_spin_unex(&pmp->xop_spin); 1050 1051 return xop; 1052 } 1053 1054 /* 1055 * Remove the completed XOP from the queue, clear HAMMER2_XOP_FIFO_RUN. 1056 * 1057 * NOTE! Xops run concurrently for each cluster index. 1058 */ 1059 static 1060 void 1061 hammer2_xop_dequeue(hammer2_thread_t *thr, hammer2_xop_head_t *xop) 1062 { 1063 hammer2_pfs_t *pmp = thr->pmp; 1064 int clindex = thr->clindex; 1065 1066 hammer2_spin_ex(&pmp->xop_spin); 1067 TAILQ_REMOVE(&thr->xopq, xop, collect[clindex].entry); 1068 atomic_clear_int(&xop->collect[clindex].flags, 1069 HAMMER2_XOP_FIFO_RUN); 1070 hammer2_spin_unex(&pmp->xop_spin); 1071 if (TAILQ_FIRST(&thr->xopq)) 1072 hammer2_thr_signal(thr, HAMMER2_THREAD_XOPQ); 1073 } 1074 1075 /* 1076 * Primary management thread for xops support. Each node has several such 1077 * threads which replicate front-end operations on cluster nodes. 1078 * 1079 * XOPS thread node operations, allowing the function to focus on a single 1080 * node in the cluster after validating the operation with the cluster. 1081 * This is primarily what prevents dead or stalled nodes from stalling 1082 * the front-end. 1083 */ 1084 void 1085 hammer2_primary_xops_thread(void *arg) 1086 { 1087 hammer2_thread_t *thr = arg; 1088 hammer2_pfs_t *pmp; 1089 hammer2_xop_head_t *xop; 1090 uint64_t mask; 1091 uint32_t flags; 1092 uint32_t nflags; 1093 hammer2_xop_desc_t *last_desc = NULL; 1094 1095 pmp = thr->pmp; 1096 /*xgrp = &pmp->xop_groups[thr->repidx]; not needed */ 1097 mask = 1LLU << thr->clindex; 1098 1099 for (;;) { 1100 flags = thr->flags; 1101 1102 /* 1103 * Handle stop request 1104 */ 1105 if (flags & HAMMER2_THREAD_STOP) 1106 break; 1107 1108 /* 1109 * Handle freeze request 1110 */ 1111 if (flags & HAMMER2_THREAD_FREEZE) { 1112 hammer2_thr_signal2(thr, HAMMER2_THREAD_FROZEN, 1113 HAMMER2_THREAD_FREEZE); 1114 continue; 1115 } 1116 1117 if (flags & HAMMER2_THREAD_UNFREEZE) { 1118 hammer2_thr_signal2(thr, 0, 1119 HAMMER2_THREAD_FROZEN | 1120 HAMMER2_THREAD_UNFREEZE); 1121 continue; 1122 } 1123 1124 /* 1125 * Force idle if frozen until unfrozen or stopped. 1126 */ 1127 if (flags & HAMMER2_THREAD_FROZEN) { 1128 hammer2_thr_wait_any(thr, 1129 HAMMER2_THREAD_UNFREEZE | 1130 HAMMER2_THREAD_STOP, 1131 0); 1132 continue; 1133 } 1134 1135 /* 1136 * Reset state on REMASTER request 1137 */ 1138 if (flags & HAMMER2_THREAD_REMASTER) { 1139 hammer2_thr_signal2(thr, 0, HAMMER2_THREAD_REMASTER); 1140 /* reset state here */ 1141 continue; 1142 } 1143 1144 /* 1145 * Process requests. Each request can be multi-queued. 1146 * 1147 * If we get behind and the frontend VOP is no longer active, 1148 * we retire the request without processing it. The callback 1149 * may also abort processing if the frontend VOP becomes 1150 * inactive. 1151 */ 1152 if (flags & HAMMER2_THREAD_XOPQ) { 1153 nflags = flags & ~HAMMER2_THREAD_XOPQ; 1154 if (!atomic_cmpset_int(&thr->flags, flags, nflags)) 1155 continue; 1156 flags = nflags; 1157 /* fall through */ 1158 } 1159 while ((xop = hammer2_xop_next(thr)) != NULL) { 1160 if (hammer2_xop_active(xop)) { 1161 last_desc = xop->desc; 1162 xop->desc->storage_func((hammer2_xop_t *)xop, 1163 thr->scratch, 1164 thr->clindex); 1165 hammer2_xop_dequeue(thr, xop); 1166 hammer2_xop_retire(xop, mask); 1167 } else { 1168 last_desc = xop->desc; 1169 hammer2_xop_feed(xop, NULL, thr->clindex, 1170 ECONNABORTED); 1171 hammer2_xop_dequeue(thr, xop); 1172 hammer2_xop_retire(xop, mask); 1173 } 1174 } 1175 1176 /* 1177 * Wait for event, interlock using THREAD_WAITING and 1178 * THREAD_SIGNAL. 1179 * 1180 * For robustness poll on a 30-second interval, but nominally 1181 * expect to be woken up. 1182 */ 1183 nflags = flags | HAMMER2_THREAD_WAITING; 1184 1185 tsleep_interlock(&thr->flags, 0); 1186 if (atomic_cmpset_int(&thr->flags, flags, nflags)) { 1187 tsleep(&thr->flags, PINTERLOCKED, "h2idle", hz*30); 1188 } 1189 } 1190 1191 #if 0 1192 /* 1193 * Cleanup / termination 1194 */ 1195 while ((xop = TAILQ_FIRST(&thr->xopq)) != NULL) { 1196 kprintf("hammer2_thread: aborting xop %s\n", xop->desc->id); 1197 TAILQ_REMOVE(&thr->xopq, xop, 1198 collect[thr->clindex].entry); 1199 hammer2_xop_retire(xop, mask); 1200 } 1201 #endif 1202 thr->td = NULL; 1203 hammer2_thr_signal(thr, HAMMER2_THREAD_STOPPED); 1204 /* thr structure can go invalid after this point */ 1205 } 1206