trim_map.c revision 277818
1/* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21/* 22 * Copyright (c) 2012 Pawel Jakub Dawidek <pawel@dawidek.net>. 23 * All rights reserved. 24 */ 25 26#include <sys/zfs_context.h> 27#include <sys/spa_impl.h> 28#include <sys/vdev_impl.h> 29#include <sys/trim_map.h> 30#include <sys/time.h> 31 32/* 33 * Calculate the zio end, upgrading based on ashift which would be 34 * done by zio_vdev_io_start. 35 * 36 * This makes free range consolidation much more effective 37 * than it would otherwise be as well as ensuring that entire 38 * blocks are invalidated by writes. 39 */ 40#define TRIM_ZIO_END(vd, offset, size) (offset + \ 41 P2ROUNDUP(size, 1ULL << vd->vdev_top->vdev_ashift)) 42 43/* Maximal segment size for ATA TRIM. */ 44#define TRIM_MAP_SIZE_FACTOR (512 << 16) 45 46#define TRIM_MAP_SEGS(size) (1 + (size) / TRIM_MAP_SIZE_FACTOR) 47 48#define TRIM_MAP_ADD(tm, ts) do { \ 49 list_insert_tail(&(tm)->tm_head, (ts)); \ 50 (tm)->tm_pending += TRIM_MAP_SEGS((ts)->ts_end - (ts)->ts_start); \ 51} while (0) 52 53#define TRIM_MAP_REM(tm, ts) do { \ 54 list_remove(&(tm)->tm_head, (ts)); \ 55 (tm)->tm_pending -= TRIM_MAP_SEGS((ts)->ts_end - (ts)->ts_start); \ 56} while (0) 57 58typedef struct trim_map { 59 list_t tm_head; /* List of segments sorted by txg. */ 60 avl_tree_t tm_queued_frees; /* AVL tree of segments waiting for TRIM. */ 61 avl_tree_t tm_inflight_frees; /* AVL tree of in-flight TRIMs. */ 62 avl_tree_t tm_inflight_writes; /* AVL tree of in-flight writes. */ 63 list_t tm_pending_writes; /* Writes blocked on in-flight frees. */ 64 kmutex_t tm_lock; 65 uint64_t tm_pending; /* Count of pending TRIMs. */ 66} trim_map_t; 67 68typedef struct trim_seg { 69 avl_node_t ts_node; /* AVL node. */ 70 list_node_t ts_next; /* List element. */ 71 uint64_t ts_start; /* Starting offset of this segment. */ 72 uint64_t ts_end; /* Ending offset (non-inclusive). */ 73 uint64_t ts_txg; /* Segment creation txg. */ 74 hrtime_t ts_time; /* Segment creation time. */ 75} trim_seg_t; 76 77extern boolean_t zfs_trim_enabled; 78 79static u_int trim_txg_delay = 32; /* Keep deleted data up to 32 TXG */ 80static u_int trim_timeout = 30; /* Keep deleted data up to 30s */ 81static u_int trim_max_interval = 1; /* 1s delays between TRIMs */ 82static u_int trim_vdev_max_pending = 10000; /* Keep up to 10K segments */ 83 84SYSCTL_DECL(_vfs_zfs); 85SYSCTL_NODE(_vfs_zfs, OID_AUTO, trim, CTLFLAG_RD, 0, "ZFS TRIM"); 86 87TUNABLE_INT("vfs.zfs.trim.txg_delay", &trim_txg_delay); 88SYSCTL_UINT(_vfs_zfs_trim, OID_AUTO, txg_delay, CTLFLAG_RWTUN, &trim_txg_delay, 89 0, "Delay TRIMs by up to this many TXGs"); 90 91TUNABLE_INT("vfs.zfs.trim.timeout", &trim_timeout); 92SYSCTL_UINT(_vfs_zfs_trim, OID_AUTO, timeout, CTLFLAG_RWTUN, &trim_timeout, 0, 93 "Delay TRIMs by up to this many seconds"); 94 95TUNABLE_INT("vfs.zfs.trim.max_interval", &trim_max_interval); 96SYSCTL_UINT(_vfs_zfs_trim, OID_AUTO, max_interval, CTLFLAG_RWTUN, 97 &trim_max_interval, 0, 98 "Maximum interval between TRIM queue processing (seconds)"); 99 100SYSCTL_DECL(_vfs_zfs_vdev); 101TUNABLE_INT("vfs.zfs.vdev.trim_max_pending", &trim_vdev_max_pending); 102SYSCTL_UINT(_vfs_zfs_vdev, OID_AUTO, trim_max_pending, CTLFLAG_RWTUN, 103 &trim_vdev_max_pending, 0, 104 "Maximum pending TRIM segments for a vdev"); 105 106 107static void trim_map_vdev_commit_done(spa_t *spa, vdev_t *vd); 108 109static int 110trim_map_seg_compare(const void *x1, const void *x2) 111{ 112 const trim_seg_t *s1 = x1; 113 const trim_seg_t *s2 = x2; 114 115 if (s1->ts_start < s2->ts_start) { 116 if (s1->ts_end > s2->ts_start) 117 return (0); 118 return (-1); 119 } 120 if (s1->ts_start > s2->ts_start) { 121 if (s1->ts_start < s2->ts_end) 122 return (0); 123 return (1); 124 } 125 return (0); 126} 127 128static int 129trim_map_zio_compare(const void *x1, const void *x2) 130{ 131 const zio_t *z1 = x1; 132 const zio_t *z2 = x2; 133 134 if (z1->io_offset < z2->io_offset) { 135 if (z1->io_offset + z1->io_size > z2->io_offset) 136 return (0); 137 return (-1); 138 } 139 if (z1->io_offset > z2->io_offset) { 140 if (z1->io_offset < z2->io_offset + z2->io_size) 141 return (0); 142 return (1); 143 } 144 return (0); 145} 146 147void 148trim_map_create(vdev_t *vd) 149{ 150 trim_map_t *tm; 151 152 ASSERT(zfs_trim_enabled && !vd->vdev_notrim && 153 vd->vdev_ops->vdev_op_leaf); 154 155 tm = kmem_zalloc(sizeof (*tm), KM_SLEEP); 156 mutex_init(&tm->tm_lock, NULL, MUTEX_DEFAULT, NULL); 157 list_create(&tm->tm_head, sizeof (trim_seg_t), 158 offsetof(trim_seg_t, ts_next)); 159 list_create(&tm->tm_pending_writes, sizeof (zio_t), 160 offsetof(zio_t, io_trim_link)); 161 avl_create(&tm->tm_queued_frees, trim_map_seg_compare, 162 sizeof (trim_seg_t), offsetof(trim_seg_t, ts_node)); 163 avl_create(&tm->tm_inflight_frees, trim_map_seg_compare, 164 sizeof (trim_seg_t), offsetof(trim_seg_t, ts_node)); 165 avl_create(&tm->tm_inflight_writes, trim_map_zio_compare, 166 sizeof (zio_t), offsetof(zio_t, io_trim_node)); 167 vd->vdev_trimmap = tm; 168} 169 170void 171trim_map_destroy(vdev_t *vd) 172{ 173 trim_map_t *tm; 174 trim_seg_t *ts; 175 176 ASSERT(vd->vdev_ops->vdev_op_leaf); 177 178 if (!zfs_trim_enabled) 179 return; 180 181 tm = vd->vdev_trimmap; 182 if (tm == NULL) 183 return; 184 185 /* 186 * We may have been called before trim_map_vdev_commit_done() 187 * had a chance to run, so do it now to prune the remaining 188 * inflight frees. 189 */ 190 trim_map_vdev_commit_done(vd->vdev_spa, vd); 191 192 mutex_enter(&tm->tm_lock); 193 while ((ts = list_head(&tm->tm_head)) != NULL) { 194 avl_remove(&tm->tm_queued_frees, ts); 195 TRIM_MAP_REM(tm, ts); 196 kmem_free(ts, sizeof (*ts)); 197 } 198 mutex_exit(&tm->tm_lock); 199 200 avl_destroy(&tm->tm_queued_frees); 201 avl_destroy(&tm->tm_inflight_frees); 202 avl_destroy(&tm->tm_inflight_writes); 203 list_destroy(&tm->tm_pending_writes); 204 list_destroy(&tm->tm_head); 205 mutex_destroy(&tm->tm_lock); 206 kmem_free(tm, sizeof (*tm)); 207 vd->vdev_trimmap = NULL; 208} 209 210static void 211trim_map_segment_add(trim_map_t *tm, uint64_t start, uint64_t end, uint64_t txg) 212{ 213 avl_index_t where; 214 trim_seg_t tsearch, *ts_before, *ts_after, *ts; 215 boolean_t merge_before, merge_after; 216 hrtime_t time; 217 218 ASSERT(MUTEX_HELD(&tm->tm_lock)); 219 VERIFY(start < end); 220 221 time = gethrtime(); 222 tsearch.ts_start = start; 223 tsearch.ts_end = end; 224 225 ts = avl_find(&tm->tm_queued_frees, &tsearch, &where); 226 if (ts != NULL) { 227 if (start < ts->ts_start) 228 trim_map_segment_add(tm, start, ts->ts_start, txg); 229 if (end > ts->ts_end) 230 trim_map_segment_add(tm, ts->ts_end, end, txg); 231 return; 232 } 233 234 ts_before = avl_nearest(&tm->tm_queued_frees, where, AVL_BEFORE); 235 ts_after = avl_nearest(&tm->tm_queued_frees, where, AVL_AFTER); 236 237 merge_before = (ts_before != NULL && ts_before->ts_end == start); 238 merge_after = (ts_after != NULL && ts_after->ts_start == end); 239 240 if (merge_before && merge_after) { 241 avl_remove(&tm->tm_queued_frees, ts_before); 242 TRIM_MAP_REM(tm, ts_before); 243 TRIM_MAP_REM(tm, ts_after); 244 ts_after->ts_start = ts_before->ts_start; 245 ts_after->ts_txg = txg; 246 ts_after->ts_time = time; 247 TRIM_MAP_ADD(tm, ts_after); 248 kmem_free(ts_before, sizeof (*ts_before)); 249 } else if (merge_before) { 250 TRIM_MAP_REM(tm, ts_before); 251 ts_before->ts_end = end; 252 ts_before->ts_txg = txg; 253 ts_before->ts_time = time; 254 TRIM_MAP_ADD(tm, ts_before); 255 } else if (merge_after) { 256 TRIM_MAP_REM(tm, ts_after); 257 ts_after->ts_start = start; 258 ts_after->ts_txg = txg; 259 ts_after->ts_time = time; 260 TRIM_MAP_ADD(tm, ts_after); 261 } else { 262 ts = kmem_alloc(sizeof (*ts), KM_SLEEP); 263 ts->ts_start = start; 264 ts->ts_end = end; 265 ts->ts_txg = txg; 266 ts->ts_time = time; 267 avl_insert(&tm->tm_queued_frees, ts, where); 268 TRIM_MAP_ADD(tm, ts); 269 } 270} 271 272static void 273trim_map_segment_remove(trim_map_t *tm, trim_seg_t *ts, uint64_t start, 274 uint64_t end) 275{ 276 trim_seg_t *nts; 277 boolean_t left_over, right_over; 278 279 ASSERT(MUTEX_HELD(&tm->tm_lock)); 280 281 left_over = (ts->ts_start < start); 282 right_over = (ts->ts_end > end); 283 284 TRIM_MAP_REM(tm, ts); 285 if (left_over && right_over) { 286 nts = kmem_alloc(sizeof (*nts), KM_SLEEP); 287 nts->ts_start = end; 288 nts->ts_end = ts->ts_end; 289 nts->ts_txg = ts->ts_txg; 290 nts->ts_time = ts->ts_time; 291 ts->ts_end = start; 292 avl_insert_here(&tm->tm_queued_frees, nts, ts, AVL_AFTER); 293 TRIM_MAP_ADD(tm, ts); 294 TRIM_MAP_ADD(tm, nts); 295 } else if (left_over) { 296 ts->ts_end = start; 297 TRIM_MAP_ADD(tm, ts); 298 } else if (right_over) { 299 ts->ts_start = end; 300 TRIM_MAP_ADD(tm, ts); 301 } else { 302 avl_remove(&tm->tm_queued_frees, ts); 303 kmem_free(ts, sizeof (*ts)); 304 } 305} 306 307static void 308trim_map_free_locked(trim_map_t *tm, uint64_t start, uint64_t end, uint64_t txg) 309{ 310 zio_t zsearch, *zs; 311 312 ASSERT(MUTEX_HELD(&tm->tm_lock)); 313 314 zsearch.io_offset = start; 315 zsearch.io_size = end - start; 316 317 zs = avl_find(&tm->tm_inflight_writes, &zsearch, NULL); 318 if (zs == NULL) { 319 trim_map_segment_add(tm, start, end, txg); 320 return; 321 } 322 if (start < zs->io_offset) 323 trim_map_free_locked(tm, start, zs->io_offset, txg); 324 if (zs->io_offset + zs->io_size < end) 325 trim_map_free_locked(tm, zs->io_offset + zs->io_size, end, txg); 326} 327 328void 329trim_map_free(vdev_t *vd, uint64_t offset, uint64_t size, uint64_t txg) 330{ 331 trim_map_t *tm = vd->vdev_trimmap; 332 333 if (!zfs_trim_enabled || vd->vdev_notrim || tm == NULL) 334 return; 335 336 mutex_enter(&tm->tm_lock); 337 trim_map_free_locked(tm, offset, TRIM_ZIO_END(vd, offset, size), txg); 338 mutex_exit(&tm->tm_lock); 339} 340 341boolean_t 342trim_map_write_start(zio_t *zio) 343{ 344 vdev_t *vd = zio->io_vd; 345 trim_map_t *tm = vd->vdev_trimmap; 346 trim_seg_t tsearch, *ts; 347 boolean_t left_over, right_over; 348 uint64_t start, end; 349 350 if (!zfs_trim_enabled || vd->vdev_notrim || tm == NULL) 351 return (B_TRUE); 352 353 start = zio->io_offset; 354 end = TRIM_ZIO_END(zio->io_vd, start, zio->io_size); 355 tsearch.ts_start = start; 356 tsearch.ts_end = end; 357 358 mutex_enter(&tm->tm_lock); 359 360 /* 361 * Checking for colliding in-flight frees. 362 */ 363 ts = avl_find(&tm->tm_inflight_frees, &tsearch, NULL); 364 if (ts != NULL) { 365 list_insert_tail(&tm->tm_pending_writes, zio); 366 mutex_exit(&tm->tm_lock); 367 return (B_FALSE); 368 } 369 370 ts = avl_find(&tm->tm_queued_frees, &tsearch, NULL); 371 if (ts != NULL) { 372 /* 373 * Loop until all overlapping segments are removed. 374 */ 375 do { 376 trim_map_segment_remove(tm, ts, start, end); 377 ts = avl_find(&tm->tm_queued_frees, &tsearch, NULL); 378 } while (ts != NULL); 379 } 380 avl_add(&tm->tm_inflight_writes, zio); 381 382 mutex_exit(&tm->tm_lock); 383 384 return (B_TRUE); 385} 386 387void 388trim_map_write_done(zio_t *zio) 389{ 390 vdev_t *vd = zio->io_vd; 391 trim_map_t *tm = vd->vdev_trimmap; 392 393 /* 394 * Don't check for vdev_notrim, since the write could have 395 * started before vdev_notrim was set. 396 */ 397 if (!zfs_trim_enabled || tm == NULL) 398 return; 399 400 mutex_enter(&tm->tm_lock); 401 /* 402 * Don't fail if the write isn't in the tree, since the write 403 * could have started after vdev_notrim was set. 404 */ 405 if (zio->io_trim_node.avl_child[0] || 406 zio->io_trim_node.avl_child[1] || 407 AVL_XPARENT(&zio->io_trim_node) || 408 tm->tm_inflight_writes.avl_root == &zio->io_trim_node) 409 avl_remove(&tm->tm_inflight_writes, zio); 410 mutex_exit(&tm->tm_lock); 411} 412 413/* 414 * Return the oldest segment (the one with the lowest txg / time) or NULL if: 415 * 1. The list is empty 416 * 2. The first element's txg is greater than txgsafe 417 * 3. The first element's txg is not greater than the txg argument and the 418 * the first element's time is not greater than time argument 419 */ 420static trim_seg_t * 421trim_map_first(trim_map_t *tm, uint64_t txg, uint64_t txgsafe, hrtime_t time, 422 boolean_t force) 423{ 424 trim_seg_t *ts; 425 426 ASSERT(MUTEX_HELD(&tm->tm_lock)); 427 VERIFY(txgsafe >= txg); 428 429 ts = list_head(&tm->tm_head); 430 if (ts != NULL && ts->ts_txg <= txgsafe && 431 (ts->ts_txg <= txg || ts->ts_time <= time || force)) 432 return (ts); 433 return (NULL); 434} 435 436static void 437trim_map_vdev_commit(spa_t *spa, zio_t *zio, vdev_t *vd) 438{ 439 trim_map_t *tm = vd->vdev_trimmap; 440 trim_seg_t *ts; 441 uint64_t size, offset, txgtarget, txgsafe; 442 int64_t hard, soft; 443 hrtime_t timelimit; 444 445 ASSERT(vd->vdev_ops->vdev_op_leaf); 446 447 if (tm == NULL) 448 return; 449 450 timelimit = gethrtime() - trim_timeout * NANOSEC; 451 if (vd->vdev_isl2cache) { 452 txgsafe = UINT64_MAX; 453 txgtarget = UINT64_MAX; 454 } else { 455 txgsafe = MIN(spa_last_synced_txg(spa), spa_freeze_txg(spa)); 456 if (txgsafe > trim_txg_delay) 457 txgtarget = txgsafe - trim_txg_delay; 458 else 459 txgtarget = 0; 460 } 461 462 mutex_enter(&tm->tm_lock); 463 hard = 0; 464 if (tm->tm_pending > trim_vdev_max_pending) 465 hard = (tm->tm_pending - trim_vdev_max_pending) / 4; 466 soft = P2ROUNDUP(hard + tm->tm_pending / trim_timeout + 1, 64); 467 /* Loop until we have sent all outstanding free's */ 468 while (soft > 0 && 469 (ts = trim_map_first(tm, txgtarget, txgsafe, timelimit, hard > 0)) 470 != NULL) { 471 TRIM_MAP_REM(tm, ts); 472 avl_remove(&tm->tm_queued_frees, ts); 473 avl_add(&tm->tm_inflight_frees, ts); 474 size = ts->ts_end - ts->ts_start; 475 offset = ts->ts_start; 476 /* 477 * We drop the lock while we call zio_nowait as the IO 478 * scheduler can result in a different IO being run e.g. 479 * a write which would result in a recursive lock. 480 */ 481 mutex_exit(&tm->tm_lock); 482 483 zio_nowait(zio_trim(zio, spa, vd, offset, size)); 484 485 soft -= TRIM_MAP_SEGS(size); 486 hard -= TRIM_MAP_SEGS(size); 487 mutex_enter(&tm->tm_lock); 488 } 489 mutex_exit(&tm->tm_lock); 490} 491 492static void 493trim_map_vdev_commit_done(spa_t *spa, vdev_t *vd) 494{ 495 trim_map_t *tm = vd->vdev_trimmap; 496 trim_seg_t *ts; 497 list_t pending_writes; 498 zio_t *zio; 499 uint64_t start, size; 500 void *cookie; 501 502 ASSERT(vd->vdev_ops->vdev_op_leaf); 503 504 if (tm == NULL) 505 return; 506 507 mutex_enter(&tm->tm_lock); 508 if (!avl_is_empty(&tm->tm_inflight_frees)) { 509 cookie = NULL; 510 while ((ts = avl_destroy_nodes(&tm->tm_inflight_frees, 511 &cookie)) != NULL) { 512 kmem_free(ts, sizeof (*ts)); 513 } 514 } 515 list_create(&pending_writes, sizeof (zio_t), offsetof(zio_t, 516 io_trim_link)); 517 list_move_tail(&pending_writes, &tm->tm_pending_writes); 518 mutex_exit(&tm->tm_lock); 519 520 while ((zio = list_remove_head(&pending_writes)) != NULL) { 521 zio_vdev_io_reissue(zio); 522 zio_execute(zio); 523 } 524 list_destroy(&pending_writes); 525} 526 527static void 528trim_map_commit(spa_t *spa, zio_t *zio, vdev_t *vd) 529{ 530 int c; 531 532 if (vd == NULL) 533 return; 534 535 if (vd->vdev_ops->vdev_op_leaf) { 536 trim_map_vdev_commit(spa, zio, vd); 537 } else { 538 for (c = 0; c < vd->vdev_children; c++) 539 trim_map_commit(spa, zio, vd->vdev_child[c]); 540 } 541} 542 543static void 544trim_map_commit_done(spa_t *spa, vdev_t *vd) 545{ 546 int c; 547 548 if (vd == NULL) 549 return; 550 551 if (vd->vdev_ops->vdev_op_leaf) { 552 trim_map_vdev_commit_done(spa, vd); 553 } else { 554 for (c = 0; c < vd->vdev_children; c++) 555 trim_map_commit_done(spa, vd->vdev_child[c]); 556 } 557} 558 559static void 560trim_thread(void *arg) 561{ 562 spa_t *spa = arg; 563 zio_t *zio; 564 565#ifdef _KERNEL 566 (void) snprintf(curthread->td_name, sizeof(curthread->td_name), 567 "trim %s", spa_name(spa)); 568#endif 569 570 for (;;) { 571 mutex_enter(&spa->spa_trim_lock); 572 if (spa->spa_trim_thread == NULL) { 573 spa->spa_trim_thread = curthread; 574 cv_signal(&spa->spa_trim_cv); 575 mutex_exit(&spa->spa_trim_lock); 576 thread_exit(); 577 } 578 579 (void) cv_timedwait(&spa->spa_trim_cv, &spa->spa_trim_lock, 580 hz * trim_max_interval); 581 mutex_exit(&spa->spa_trim_lock); 582 583 zio = zio_root(spa, NULL, NULL, ZIO_FLAG_CANFAIL); 584 585 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); 586 trim_map_commit(spa, zio, spa->spa_root_vdev); 587 (void) zio_wait(zio); 588 trim_map_commit_done(spa, spa->spa_root_vdev); 589 spa_config_exit(spa, SCL_STATE, FTAG); 590 } 591} 592 593void 594trim_thread_create(spa_t *spa) 595{ 596 597 if (!zfs_trim_enabled) 598 return; 599 600 mutex_init(&spa->spa_trim_lock, NULL, MUTEX_DEFAULT, NULL); 601 cv_init(&spa->spa_trim_cv, NULL, CV_DEFAULT, NULL); 602 mutex_enter(&spa->spa_trim_lock); 603 spa->spa_trim_thread = thread_create(NULL, 0, trim_thread, spa, 0, &p0, 604 TS_RUN, minclsyspri); 605 mutex_exit(&spa->spa_trim_lock); 606} 607 608void 609trim_thread_destroy(spa_t *spa) 610{ 611 612 if (!zfs_trim_enabled) 613 return; 614 if (spa->spa_trim_thread == NULL) 615 return; 616 617 mutex_enter(&spa->spa_trim_lock); 618 /* Setting spa_trim_thread to NULL tells the thread to stop. */ 619 spa->spa_trim_thread = NULL; 620 cv_signal(&spa->spa_trim_cv); 621 /* The thread will set it back to != NULL on exit. */ 622 while (spa->spa_trim_thread == NULL) 623 cv_wait(&spa->spa_trim_cv, &spa->spa_trim_lock); 624 spa->spa_trim_thread = NULL; 625 mutex_exit(&spa->spa_trim_lock); 626 627 cv_destroy(&spa->spa_trim_cv); 628 mutex_destroy(&spa->spa_trim_lock); 629} 630 631void 632trim_thread_wakeup(spa_t *spa) 633{ 634 635 if (!zfs_trim_enabled) 636 return; 637 if (spa->spa_trim_thread == NULL) 638 return; 639 640 mutex_enter(&spa->spa_trim_lock); 641 cv_signal(&spa->spa_trim_cv); 642 mutex_exit(&spa->spa_trim_lock); 643} 644