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sys/vm/vm_reserv.c
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1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2002-2006 Rice University 5 * Copyright (c) 2007-2011 Alan L. Cox <alc@cs.rice.edu> 6 * All rights reserved. 7 * 8 * This software was developed for the FreeBSD Project by Alan L. Cox, 9 * Olivier Crameri, Peter Druschel, Sitaram Iyer, and Juan Navarro. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 23 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 24 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY 30 * WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 * POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 /* 35 * Superpage reservation management module 36 * 37 * Any external functions defined by this module are only to be used by the 38 * virtual memory system. 39 */ 40 41 #include <sys/cdefs.h> 42 __FBSDID("$FreeBSD$"); 43 44 #include "opt_vm.h" 45 46 #include <sys/param.h> 47 #include <sys/kernel.h> 48 #include <sys/lock.h> 49 #include <sys/malloc.h> 50 #include <sys/mutex.h> 51 #include <sys/queue.h> 52 #include <sys/rwlock.h> 53 #include <sys/sbuf.h> 54 #include <sys/sysctl.h> 55 #include <sys/systm.h> 56 #include <sys/bitstring.h> 57 #include <sys/counter.h> 58 #include <sys/ktr.h> 59 #include <sys/vmmeter.h> 60 #include <sys/smp.h> 61 62 #include <vm/vm.h> 63 #include <vm/vm_extern.h> 64 #include <vm/vm_param.h> 65 #include <vm/vm_object.h> 66 #include <vm/vm_page.h> 67 #include <vm/vm_pageout.h> 68 #include <vm/vm_pagequeue.h> 69 #include <vm/vm_phys.h> 70 #include <vm/vm_radix.h> 71 #include <vm/vm_reserv.h> 72 73 /* 74 * The reservation system supports the speculative allocation of large physical 75 * pages ("superpages"). Speculative allocation enables the fully automatic 76 * utilization of superpages by the virtual memory system. In other words, no 77 * programmatic directives are required to use superpages. 78 */ 79 80 #if VM_NRESERVLEVEL > 0 81 82 #ifndef VM_LEVEL_0_ORDER_MAX 83 #define VM_LEVEL_0_ORDER_MAX VM_LEVEL_0_ORDER 84 #endif 85 86 /* 87 * The number of small pages that are contained in a level 0 reservation 88 */ 89 #define VM_LEVEL_0_NPAGES (1 << VM_LEVEL_0_ORDER) 90 #define VM_LEVEL_0_NPAGES_MAX (1 << VM_LEVEL_0_ORDER_MAX) 91 92 /* 93 * The number of bits by which a physical address is shifted to obtain the 94 * reservation number 95 */ 96 #define VM_LEVEL_0_SHIFT (VM_LEVEL_0_ORDER + PAGE_SHIFT) 97 98 /* 99 * The size of a level 0 reservation in bytes 100 */ 101 #define VM_LEVEL_0_SIZE (1 << VM_LEVEL_0_SHIFT) 102 103 /* 104 * Computes the index of the small page underlying the given (object, pindex) 105 * within the reservation's array of small pages. 106 */ 107 #define VM_RESERV_INDEX(object, pindex) \ 108 (((object)->pg_color + (pindex)) & (VM_LEVEL_0_NPAGES - 1)) 109 110 /* 111 * Number of elapsed ticks before we update the LRU queue position. Used 112 * to reduce contention and churn on the list. 113 */ 114 #define PARTPOPSLOP 1 115 116 /* 117 * The reservation structure 118 * 119 * A reservation structure is constructed whenever a large physical page is 120 * speculatively allocated to an object. The reservation provides the small 121 * physical pages for the range [pindex, pindex + VM_LEVEL_0_NPAGES) of offsets 122 * within that object. The reservation's "popcnt" tracks the number of these 123 * small physical pages that are in use at any given time. When and if the 124 * reservation is not fully utilized, it appears in the queue of partially 125 * populated reservations. The reservation always appears on the containing 126 * object's list of reservations. 127 * 128 * A partially populated reservation can be broken and reclaimed at any time. 129 * 130 * c - constant after boot 131 * d - vm_reserv_domain_lock 132 * o - vm_reserv_object_lock 133 * r - vm_reserv_lock 134 * s - vm_reserv_domain_scan_lock 135 */ 136 struct vm_reserv { 137 struct mtx lock; /* reservation lock. */ 138 TAILQ_ENTRY(vm_reserv) partpopq; /* (d, r) per-domain queue. */ 139 LIST_ENTRY(vm_reserv) objq; /* (o, r) object queue */ 140 vm_object_t object; /* (o, r) containing object */ 141 vm_pindex_t pindex; /* (o, r) offset in object */ 142 vm_page_t pages; /* (c) first page */ 143 uint16_t popcnt; /* (r) # of pages in use */ 144 uint8_t domain; /* (c) NUMA domain. */ 145 char inpartpopq; /* (d, r) */ 146 int lasttick; /* (r) last pop update tick. */ 147 bitstr_t bit_decl(popmap, VM_LEVEL_0_NPAGES_MAX); 148 /* (r) bit vector, used pages */ 149 }; 150 151 TAILQ_HEAD(vm_reserv_queue, vm_reserv); 152 153 #define vm_reserv_lockptr(rv) (&(rv)->lock) 154 #define vm_reserv_assert_locked(rv) \ 155 mtx_assert(vm_reserv_lockptr(rv), MA_OWNED) 156 #define vm_reserv_lock(rv) mtx_lock(vm_reserv_lockptr(rv)) 157 #define vm_reserv_trylock(rv) mtx_trylock(vm_reserv_lockptr(rv)) 158 #define vm_reserv_unlock(rv) mtx_unlock(vm_reserv_lockptr(rv)) 159 160 /* 161 * The reservation array 162 * 163 * This array is analoguous in function to vm_page_array. It differs in the 164 * respect that it may contain a greater number of useful reservation 165 * structures than there are (physical) superpages. These "invalid" 166 * reservation structures exist to trade-off space for time in the 167 * implementation of vm_reserv_from_page(). Invalid reservation structures are 168 * distinguishable from "valid" reservation structures by inspecting the 169 * reservation's "pages" field. Invalid reservation structures have a NULL 170 * "pages" field. 171 * 172 * vm_reserv_from_page() maps a small (physical) page to an element of this 173 * array by computing a physical reservation number from the page's physical 174 * address. The physical reservation number is used as the array index. 175 * 176 * An "active" reservation is a valid reservation structure that has a non-NULL 177 * "object" field and a non-zero "popcnt" field. In other words, every active 178 * reservation belongs to a particular object. Moreover, every active 179 * reservation has an entry in the containing object's list of reservations. 180 */ 181 static vm_reserv_t vm_reserv_array; 182 183 /* 184 * The per-domain partially populated reservation queues 185 * 186 * These queues enable the fast recovery of an unused free small page from a 187 * partially populated reservation. The reservation at the head of a queue 188 * is the least recently changed, partially populated reservation. 189 * 190 * Access to this queue is synchronized by the per-domain reservation lock. 191 * Threads reclaiming free pages from the queue must hold the per-domain scan 192 * lock. 193 */ 194 struct vm_reserv_domain { 195 struct mtx lock; 196 struct vm_reserv_queue partpop; /* (d) */ 197 struct vm_reserv marker; /* (d, s) scan marker/lock */ 198 } __aligned(CACHE_LINE_SIZE); 199 200 static struct vm_reserv_domain vm_rvd[MAXMEMDOM]; 201 202 #define vm_reserv_domain_lockptr(d) (&vm_rvd[(d)].lock) 203 #define vm_reserv_domain_assert_locked(d) \ 204 mtx_assert(vm_reserv_domain_lockptr(d), MA_OWNED) 205 #define vm_reserv_domain_lock(d) mtx_lock(vm_reserv_domain_lockptr(d)) 206 #define vm_reserv_domain_unlock(d) mtx_unlock(vm_reserv_domain_lockptr(d)) 207 208 #define vm_reserv_domain_scan_lock(d) mtx_lock(&vm_rvd[(d)].marker.lock) 209 #define vm_reserv_domain_scan_unlock(d) mtx_unlock(&vm_rvd[(d)].marker.lock) 210 211 static SYSCTL_NODE(_vm, OID_AUTO, reserv, CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 212 "Reservation Info"); 213 214 static COUNTER_U64_DEFINE_EARLY(vm_reserv_broken); 215 SYSCTL_COUNTER_U64(_vm_reserv, OID_AUTO, broken, CTLFLAG_RD, 216 &vm_reserv_broken, "Cumulative number of broken reservations"); 217 218 static COUNTER_U64_DEFINE_EARLY(vm_reserv_freed); 219 SYSCTL_COUNTER_U64(_vm_reserv, OID_AUTO, freed, CTLFLAG_RD, 220 &vm_reserv_freed, "Cumulative number of freed reservations"); 221 222 static int sysctl_vm_reserv_fullpop(SYSCTL_HANDLER_ARGS); 223 224 SYSCTL_PROC(_vm_reserv, OID_AUTO, fullpop, CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RD, 225 NULL, 0, sysctl_vm_reserv_fullpop, "I", "Current number of full reservations"); 226 227 static int sysctl_vm_reserv_partpopq(SYSCTL_HANDLER_ARGS); 228 229 SYSCTL_OID(_vm_reserv, OID_AUTO, partpopq, 230 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 231 sysctl_vm_reserv_partpopq, "A", 232 "Partially populated reservation queues"); 233 234 static COUNTER_U64_DEFINE_EARLY(vm_reserv_reclaimed); 235 SYSCTL_COUNTER_U64(_vm_reserv, OID_AUTO, reclaimed, CTLFLAG_RD, 236 &vm_reserv_reclaimed, "Cumulative number of reclaimed reservations"); 237 238 /* 239 * The object lock pool is used to synchronize the rvq. We can not use a 240 * pool mutex because it is required before malloc works. 241 * 242 * The "hash" function could be made faster without divide and modulo. 243 */ 244 #define VM_RESERV_OBJ_LOCK_COUNT MAXCPU 245 246 struct mtx_padalign vm_reserv_object_mtx[VM_RESERV_OBJ_LOCK_COUNT]; 247 248 #define vm_reserv_object_lock_idx(object) \ 249 (((uintptr_t)object / sizeof(*object)) % VM_RESERV_OBJ_LOCK_COUNT) 250 #define vm_reserv_object_lock_ptr(object) \ 251 &vm_reserv_object_mtx[vm_reserv_object_lock_idx((object))] 252 #define vm_reserv_object_lock(object) \ 253 mtx_lock(vm_reserv_object_lock_ptr((object))) 254 #define vm_reserv_object_unlock(object) \ 255 mtx_unlock(vm_reserv_object_lock_ptr((object))) 256 257 static void vm_reserv_break(vm_reserv_t rv); 258 static void vm_reserv_depopulate(vm_reserv_t rv, int index); 259 static vm_reserv_t vm_reserv_from_page(vm_page_t m); 260 static boolean_t vm_reserv_has_pindex(vm_reserv_t rv, 261 vm_pindex_t pindex); 262 static void vm_reserv_populate(vm_reserv_t rv, int index); 263 static void vm_reserv_reclaim(vm_reserv_t rv); 264 265 /* 266 * Returns the current number of full reservations. 267 * 268 * Since the number of full reservations is computed without acquiring any 269 * locks, the returned value is inexact. 270 */ 271 static int 272 sysctl_vm_reserv_fullpop(SYSCTL_HANDLER_ARGS) 273 { 274 vm_paddr_t paddr; 275 struct vm_phys_seg *seg; 276 vm_reserv_t rv; 277 int fullpop, segind; 278 279 fullpop = 0; 280 for (segind = 0; segind < vm_phys_nsegs; segind++) { 281 seg = &vm_phys_segs[segind]; 282 paddr = roundup2(seg->start, VM_LEVEL_0_SIZE); 283 #ifdef VM_PHYSSEG_SPARSE 284 rv = seg->first_reserv + (paddr >> VM_LEVEL_0_SHIFT) - 285 (seg->start >> VM_LEVEL_0_SHIFT); 286 #else 287 rv = &vm_reserv_array[paddr >> VM_LEVEL_0_SHIFT]; 288 #endif 289 while (paddr + VM_LEVEL_0_SIZE > paddr && paddr + 290 VM_LEVEL_0_SIZE <= seg->end) { 291 fullpop += rv->popcnt == VM_LEVEL_0_NPAGES; 292 paddr += VM_LEVEL_0_SIZE; 293 rv++; 294 } 295 } 296 return (sysctl_handle_int(oidp, &fullpop, 0, req)); 297 } 298 299 /* 300 * Describes the current state of the partially populated reservation queue. 301 */ 302 static int 303 sysctl_vm_reserv_partpopq(SYSCTL_HANDLER_ARGS) 304 { 305 struct sbuf sbuf; 306 vm_reserv_t rv; 307 int counter, error, domain, level, unused_pages; 308 309 error = sysctl_wire_old_buffer(req, 0); 310 if (error != 0) 311 return (error); 312 sbuf_new_for_sysctl(&sbuf, NULL, 128, req); 313 sbuf_printf(&sbuf, "\nDOMAIN LEVEL SIZE NUMBER\n\n"); 314 for (domain = 0; domain < vm_ndomains; domain++) { 315 for (level = -1; level <= VM_NRESERVLEVEL - 2; level++) { 316 counter = 0; 317 unused_pages = 0; 318 vm_reserv_domain_lock(domain); 319 TAILQ_FOREACH(rv, &vm_rvd[domain].partpop, partpopq) { 320 if (rv == &vm_rvd[domain].marker) 321 continue; 322 counter++; 323 unused_pages += VM_LEVEL_0_NPAGES - rv->popcnt; 324 } 325 vm_reserv_domain_unlock(domain); 326 sbuf_printf(&sbuf, "%6d, %7d, %6dK, %6d\n", 327 domain, level, 328 unused_pages * ((int)PAGE_SIZE / 1024), counter); 329 } 330 } 331 error = sbuf_finish(&sbuf); 332 sbuf_delete(&sbuf); 333 return (error); 334 } 335 336 /* 337 * Remove a reservation from the object's objq. 338 */ 339 static void 340 vm_reserv_remove(vm_reserv_t rv) 341 { 342 vm_object_t object; 343 344 vm_reserv_assert_locked(rv); 345 CTR5(KTR_VM, "%s: rv %p object %p popcnt %d inpartpop %d", 346 __FUNCTION__, rv, rv->object, rv->popcnt, rv->inpartpopq); 347 KASSERT(rv->object != NULL, 348 ("vm_reserv_remove: reserv %p is free", rv)); 349 KASSERT(!rv->inpartpopq, 350 ("vm_reserv_remove: reserv %p's inpartpopq is TRUE", rv)); 351 object = rv->object; 352 vm_reserv_object_lock(object); 353 LIST_REMOVE(rv, objq); 354 rv->object = NULL; 355 vm_reserv_object_unlock(object); 356 } 357 358 /* 359 * Insert a new reservation into the object's objq. 360 */ 361 static void 362 vm_reserv_insert(vm_reserv_t rv, vm_object_t object, vm_pindex_t pindex) 363 { 364 365 vm_reserv_assert_locked(rv); 366 CTR6(KTR_VM, 367 "%s: rv %p(%p) object %p new %p popcnt %d", 368 __FUNCTION__, rv, rv->pages, rv->object, object, 369 rv->popcnt); 370 KASSERT(rv->object == NULL, 371 ("vm_reserv_insert: reserv %p isn't free", rv)); 372 KASSERT(rv->popcnt == 0, 373 ("vm_reserv_insert: reserv %p's popcnt is corrupted", rv)); 374 KASSERT(!rv->inpartpopq, 375 ("vm_reserv_insert: reserv %p's inpartpopq is TRUE", rv)); 376 KASSERT(bit_ntest(rv->popmap, 0, VM_LEVEL_0_NPAGES - 1, 0), 377 ("vm_reserv_insert: reserv %p's popmap is corrupted", rv)); 378 vm_reserv_object_lock(object); 379 rv->pindex = pindex; 380 rv->object = object; 381 rv->lasttick = ticks; 382 LIST_INSERT_HEAD(&object->rvq, rv, objq); 383 vm_reserv_object_unlock(object); 384 } 385 386 /* 387 * Reduces the given reservation's population count. If the population count 388 * becomes zero, the reservation is destroyed. Additionally, moves the 389 * reservation to the tail of the partially populated reservation queue if the 390 * population count is non-zero. 391 */ 392 static void 393 vm_reserv_depopulate(vm_reserv_t rv, int index) 394 { 395 struct vm_domain *vmd; 396 397 vm_reserv_assert_locked(rv); 398 CTR5(KTR_VM, "%s: rv %p object %p popcnt %d inpartpop %d", 399 __FUNCTION__, rv, rv->object, rv->popcnt, rv->inpartpopq); 400 KASSERT(rv->object != NULL, 401 ("vm_reserv_depopulate: reserv %p is free", rv)); 402 KASSERT(bit_test(rv->popmap, index), 403 ("vm_reserv_depopulate: reserv %p's popmap[%d] is clear", rv, 404 index)); 405 KASSERT(rv->popcnt > 0, 406 ("vm_reserv_depopulate: reserv %p's popcnt is corrupted", rv)); 407 KASSERT(rv->domain < vm_ndomains, 408 ("vm_reserv_depopulate: reserv %p's domain is corrupted %d", 409 rv, rv->domain)); 410 if (rv->popcnt == VM_LEVEL_0_NPAGES) { 411 KASSERT(rv->pages->psind == 1, 412 ("vm_reserv_depopulate: reserv %p is already demoted", 413 rv)); 414 rv->pages->psind = 0; 415 } 416 bit_clear(rv->popmap, index); 417 rv->popcnt--; 418 if ((unsigned)(ticks - rv->lasttick) >= PARTPOPSLOP || 419 rv->popcnt == 0) { 420 vm_reserv_domain_lock(rv->domain); 421 if (rv->inpartpopq) { 422 TAILQ_REMOVE(&vm_rvd[rv->domain].partpop, rv, partpopq); 423 rv->inpartpopq = FALSE; 424 } 425 if (rv->popcnt != 0) { 426 rv->inpartpopq = TRUE; 427 TAILQ_INSERT_TAIL(&vm_rvd[rv->domain].partpop, rv, 428 partpopq); 429 } 430 vm_reserv_domain_unlock(rv->domain); 431 rv->lasttick = ticks; 432 } 433 vmd = VM_DOMAIN(rv->domain); 434 if (rv->popcnt == 0) { 435 vm_reserv_remove(rv); 436 vm_domain_free_lock(vmd); 437 vm_phys_free_pages(rv->pages, VM_LEVEL_0_ORDER); 438 vm_domain_free_unlock(vmd); 439 counter_u64_add(vm_reserv_freed, 1); 440 } 441 vm_domain_freecnt_inc(vmd, 1); 442 } 443 444 /* 445 * Returns the reservation to which the given page might belong. 446 */ 447 static __inline vm_reserv_t 448 vm_reserv_from_page(vm_page_t m) 449 { 450 #ifdef VM_PHYSSEG_SPARSE 451 struct vm_phys_seg *seg; 452 453 seg = &vm_phys_segs[m->segind]; 454 return (seg->first_reserv + (VM_PAGE_TO_PHYS(m) >> VM_LEVEL_0_SHIFT) - 455 (seg->start >> VM_LEVEL_0_SHIFT)); 456 #else 457 return (&vm_reserv_array[VM_PAGE_TO_PHYS(m) >> VM_LEVEL_0_SHIFT]); 458 #endif 459 } 460 461 /* 462 * Returns an existing reservation or NULL and initialized successor pointer. 463 */ 464 static vm_reserv_t 465 vm_reserv_from_object(vm_object_t object, vm_pindex_t pindex, 466 vm_page_t mpred, vm_page_t *msuccp) 467 { 468 vm_reserv_t rv; 469 vm_page_t msucc; 470 471 msucc = NULL; 472 if (mpred != NULL) { 473 KASSERT(mpred->object == object, 474 ("vm_reserv_from_object: object doesn't contain mpred")); 475 KASSERT(mpred->pindex < pindex, 476 ("vm_reserv_from_object: mpred doesn't precede pindex")); 477 rv = vm_reserv_from_page(mpred); 478 if (rv->object == object && vm_reserv_has_pindex(rv, pindex)) 479 goto found; 480 msucc = TAILQ_NEXT(mpred, listq); 481 } else 482 msucc = TAILQ_FIRST(&object->memq); 483 if (msucc != NULL) { 484 KASSERT(msucc->pindex > pindex, 485 ("vm_reserv_from_object: msucc doesn't succeed pindex")); 486 rv = vm_reserv_from_page(msucc); 487 if (rv->object == object && vm_reserv_has_pindex(rv, pindex)) 488 goto found; 489 } 490 rv = NULL; 491 492 found: 493 *msuccp = msucc; 494 495 return (rv); 496 } 497 498 /* 499 * Returns TRUE if the given reservation contains the given page index and 500 * FALSE otherwise. 501 */ 502 static __inline boolean_t 503 vm_reserv_has_pindex(vm_reserv_t rv, vm_pindex_t pindex) 504 { 505 506 return (((pindex - rv->pindex) & ~(VM_LEVEL_0_NPAGES - 1)) == 0); 507 } 508 509 /* 510 * Increases the given reservation's population count. Moves the reservation 511 * to the tail of the partially populated reservation queue. 512 */ 513 static void 514 vm_reserv_populate(vm_reserv_t rv, int index) 515 { 516 517 vm_reserv_assert_locked(rv); 518 CTR5(KTR_VM, "%s: rv %p object %p popcnt %d inpartpop %d", 519 __FUNCTION__, rv, rv->object, rv->popcnt, rv->inpartpopq); 520 KASSERT(rv->object != NULL, 521 ("vm_reserv_populate: reserv %p is free", rv)); 522 KASSERT(!bit_test(rv->popmap, index), 523 ("vm_reserv_populate: reserv %p's popmap[%d] is set", rv, 524 index)); 525 KASSERT(rv->popcnt < VM_LEVEL_0_NPAGES, 526 ("vm_reserv_populate: reserv %p is already full", rv)); 527 KASSERT(rv->pages->psind == 0, 528 ("vm_reserv_populate: reserv %p is already promoted", rv)); 529 KASSERT(rv->domain < vm_ndomains, 530 ("vm_reserv_populate: reserv %p's domain is corrupted %d", 531 rv, rv->domain)); 532 bit_set(rv->popmap, index); 533 rv->popcnt++; 534 if ((unsigned)(ticks - rv->lasttick) < PARTPOPSLOP && 535 rv->inpartpopq && rv->popcnt != VM_LEVEL_0_NPAGES) 536 return; 537 rv->lasttick = ticks; 538 vm_reserv_domain_lock(rv->domain); 539 if (rv->inpartpopq) { 540 TAILQ_REMOVE(&vm_rvd[rv->domain].partpop, rv, partpopq); 541 rv->inpartpopq = FALSE; 542 } 543 if (rv->popcnt < VM_LEVEL_0_NPAGES) { 544 rv->inpartpopq = TRUE; 545 TAILQ_INSERT_TAIL(&vm_rvd[rv->domain].partpop, rv, partpopq); 546 } else { 547 KASSERT(rv->pages->psind == 0, 548 ("vm_reserv_populate: reserv %p is already promoted", 549 rv)); 550 rv->pages->psind = 1; 551 } 552 vm_reserv_domain_unlock(rv->domain); 553 } 554 555 /* 556 * Allocates a contiguous set of physical pages of the given size "npages" 557 * from existing or newly created reservations. All of the physical pages 558 * must be at or above the given physical address "low" and below the given 559 * physical address "high". The given value "alignment" determines the 560 * alignment of the first physical page in the set. If the given value 561 * "boundary" is non-zero, then the set of physical pages cannot cross any 562 * physical address boundary that is a multiple of that value. Both 563 * "alignment" and "boundary" must be a power of two. 564 * 565 * The page "mpred" must immediately precede the offset "pindex" within the 566 * specified object. 567 * 568 * The object must be locked. 569 */ 570 vm_page_t 571 vm_reserv_alloc_contig(vm_object_t object, vm_pindex_t pindex, int domain, 572 int req, vm_page_t mpred, u_long npages, vm_paddr_t low, vm_paddr_t high, 573 u_long alignment, vm_paddr_t boundary) 574 { 575 struct vm_domain *vmd; 576 vm_paddr_t pa, size; 577 vm_page_t m, m_ret, msucc; 578 vm_pindex_t first, leftcap, rightcap; 579 vm_reserv_t rv; 580 u_long allocpages, maxpages, minpages; 581 int i, index, n; 582 583 VM_OBJECT_ASSERT_WLOCKED(object); 584 KASSERT(npages != 0, ("vm_reserv_alloc_contig: npages is 0")); 585 586 /* 587 * Is a reservation fundamentally impossible? 588 */ 589 if (pindex < VM_RESERV_INDEX(object, pindex) || 590 pindex + npages > object->size) 591 return (NULL); 592 593 /* 594 * All reservations of a particular size have the same alignment. 595 * Assuming that the first page is allocated from a reservation, the 596 * least significant bits of its physical address can be determined 597 * from its offset from the beginning of the reservation and the size 598 * of the reservation. 599 * 600 * Could the specified index within a reservation of the smallest 601 * possible size satisfy the alignment and boundary requirements? 602 */ 603 pa = VM_RESERV_INDEX(object, pindex) << PAGE_SHIFT; 604 size = npages << PAGE_SHIFT; 605 if (!vm_addr_ok(pa, size, alignment, boundary)) 606 return (NULL); 607 608 /* 609 * Look for an existing reservation. 610 */ 611 rv = vm_reserv_from_object(object, pindex, mpred, &msucc); 612 if (rv != NULL) { 613 KASSERT(object != kernel_object || rv->domain == domain, 614 ("vm_reserv_alloc_contig: domain mismatch")); 615 index = VM_RESERV_INDEX(object, pindex); 616 /* Does the allocation fit within the reservation? */ 617 if (index + npages > VM_LEVEL_0_NPAGES) 618 return (NULL); 619 domain = rv->domain; 620 vmd = VM_DOMAIN(domain); 621 vm_reserv_lock(rv); 622 /* Handle reclaim race. */ 623 if (rv->object != object) 624 goto out; 625 m = &rv->pages[index]; 626 pa = VM_PAGE_TO_PHYS(m); 627 if (pa < low || pa + size > high || 628 !vm_addr_ok(pa, size, alignment, boundary)) 629 goto out; 630 /* Handle vm_page_rename(m, new_object, ...). */ 631 if (!bit_ntest(rv->popmap, index, index + npages - 1, 0)) 632 goto out; 633 if (!vm_domain_allocate(vmd, req, npages)) 634 goto out; 635 for (i = 0; i < npages; i++) 636 vm_reserv_populate(rv, index + i); 637 vm_reserv_unlock(rv); 638 return (m); 639 out: 640 vm_reserv_unlock(rv); 641 return (NULL); 642 } 643 644 /* 645 * Could at least one reservation fit between the first index to the 646 * left that can be used ("leftcap") and the first index to the right 647 * that cannot be used ("rightcap")? 648 * 649 * We must synchronize with the reserv object lock to protect the 650 * pindex/object of the resulting reservations against rename while 651 * we are inspecting. 652 */ 653 first = pindex - VM_RESERV_INDEX(object, pindex); 654 minpages = VM_RESERV_INDEX(object, pindex) + npages; 655 maxpages = roundup2(minpages, VM_LEVEL_0_NPAGES); 656 allocpages = maxpages; 657 vm_reserv_object_lock(object); 658 if (mpred != NULL) { 659 if ((rv = vm_reserv_from_page(mpred))->object != object) 660 leftcap = mpred->pindex + 1; 661 else 662 leftcap = rv->pindex + VM_LEVEL_0_NPAGES; 663 if (leftcap > first) { 664 vm_reserv_object_unlock(object); 665 return (NULL); 666 } 667 } 668 if (msucc != NULL) { 669 if ((rv = vm_reserv_from_page(msucc))->object != object) 670 rightcap = msucc->pindex; 671 else 672 rightcap = rv->pindex; 673 if (first + maxpages > rightcap) { 674 if (maxpages == VM_LEVEL_0_NPAGES) { 675 vm_reserv_object_unlock(object); 676 return (NULL); 677 } 678 679 /* 680 * At least one reservation will fit between "leftcap" 681 * and "rightcap". However, a reservation for the 682 * last of the requested pages will not fit. Reduce 683 * the size of the upcoming allocation accordingly. 684 */ 685 allocpages = minpages; 686 } 687 } 688 vm_reserv_object_unlock(object); 689 690 /* 691 * Would the last new reservation extend past the end of the object? 692 * 693 * If the object is unlikely to grow don't allocate a reservation for 694 * the tail. 695 */ 696 if ((object->flags & OBJ_ANON) == 0 && 697 first + maxpages > object->size) { 698 if (maxpages == VM_LEVEL_0_NPAGES) 699 return (NULL); 700 allocpages = minpages; 701 } 702 703 /* 704 * Allocate the physical pages. The alignment and boundary specified 705 * for this allocation may be different from the alignment and 706 * boundary specified for the requested pages. For instance, the 707 * specified index may not be the first page within the first new 708 * reservation. 709 */ 710 m = NULL; 711 vmd = VM_DOMAIN(domain); 712 if (vm_domain_allocate(vmd, req, npages)) { 713 vm_domain_free_lock(vmd); 714 m = vm_phys_alloc_contig(domain, allocpages, low, high, 715 ulmax(alignment, VM_LEVEL_0_SIZE), 716 boundary > VM_LEVEL_0_SIZE ? boundary : 0); 717 vm_domain_free_unlock(vmd); 718 if (m == NULL) { 719 vm_domain_freecnt_inc(vmd, npages); 720 return (NULL); 721 } 722 } else 723 return (NULL); 724 KASSERT(vm_page_domain(m) == domain, 725 ("vm_reserv_alloc_contig: Page domain does not match requested.")); 726 727 /* 728 * The allocated physical pages always begin at a reservation 729 * boundary, but they do not always end at a reservation boundary. 730 * Initialize every reservation that is completely covered by the 731 * allocated physical pages. 732 */ 733 m_ret = NULL; 734 index = VM_RESERV_INDEX(object, pindex); 735 do { 736 rv = vm_reserv_from_page(m); 737 KASSERT(rv->pages == m, 738 ("vm_reserv_alloc_contig: reserv %p's pages is corrupted", 739 rv)); 740 vm_reserv_lock(rv); 741 vm_reserv_insert(rv, object, first); 742 n = ulmin(VM_LEVEL_0_NPAGES - index, npages); 743 for (i = 0; i < n; i++) 744 vm_reserv_populate(rv, index + i); 745 npages -= n; 746 if (m_ret == NULL) { 747 m_ret = &rv->pages[index]; 748 index = 0; 749 } 750 vm_reserv_unlock(rv); 751 m += VM_LEVEL_0_NPAGES; 752 first += VM_LEVEL_0_NPAGES; 753 allocpages -= VM_LEVEL_0_NPAGES; 754 } while (allocpages >= VM_LEVEL_0_NPAGES); 755 return (m_ret); 756 } 757 758 /* 759 * Allocate a physical page from an existing or newly created reservation. 760 * 761 * The page "mpred" must immediately precede the offset "pindex" within the 762 * specified object. 763 * 764 * The object must be locked. 765 */ 766 vm_page_t 767 vm_reserv_alloc_page(vm_object_t object, vm_pindex_t pindex, int domain, 768 int req, vm_page_t mpred) 769 { 770 struct vm_domain *vmd; 771 vm_page_t m, msucc; 772 vm_pindex_t first, leftcap, rightcap; 773 vm_reserv_t rv; 774 int index; 775 776 VM_OBJECT_ASSERT_WLOCKED(object); 777 778 /* 779 * Is a reservation fundamentally impossible? 780 */ 781 if (pindex < VM_RESERV_INDEX(object, pindex) || 782 pindex >= object->size) 783 return (NULL); 784 785 /* 786 * Look for an existing reservation. 787 */ 788 rv = vm_reserv_from_object(object, pindex, mpred, &msucc); 789 if (rv != NULL) { 790 KASSERT(object != kernel_object || rv->domain == domain, 791 ("vm_reserv_alloc_page: domain mismatch")); 792 domain = rv->domain; 793 vmd = VM_DOMAIN(domain); 794 index = VM_RESERV_INDEX(object, pindex); 795 m = &rv->pages[index]; 796 vm_reserv_lock(rv); 797 /* Handle reclaim race. */ 798 if (rv->object != object || 799 /* Handle vm_page_rename(m, new_object, ...). */ 800 bit_test(rv->popmap, index)) { 801 m = NULL; 802 goto out; 803 } 804 if (vm_domain_allocate(vmd, req, 1) == 0) 805 m = NULL; 806 else 807 vm_reserv_populate(rv, index); 808 out: 809 vm_reserv_unlock(rv); 810 return (m); 811 } 812 813 /* 814 * Could a reservation fit between the first index to the left that 815 * can be used and the first index to the right that cannot be used? 816 * 817 * We must synchronize with the reserv object lock to protect the 818 * pindex/object of the resulting reservations against rename while 819 * we are inspecting. 820 */ 821 first = pindex - VM_RESERV_INDEX(object, pindex); 822 vm_reserv_object_lock(object); 823 if (mpred != NULL) { 824 if ((rv = vm_reserv_from_page(mpred))->object != object) 825 leftcap = mpred->pindex + 1; 826 else 827 leftcap = rv->pindex + VM_LEVEL_0_NPAGES; 828 if (leftcap > first) { 829 vm_reserv_object_unlock(object); 830 return (NULL); 831 } 832 } 833 if (msucc != NULL) { 834 if ((rv = vm_reserv_from_page(msucc))->object != object) 835 rightcap = msucc->pindex; 836 else 837 rightcap = rv->pindex; 838 if (first + VM_LEVEL_0_NPAGES > rightcap) { 839 vm_reserv_object_unlock(object); 840 return (NULL); 841 } 842 } 843 vm_reserv_object_unlock(object); 844 845 /* 846 * Would the last new reservation extend past the end of the object? 847 * 848 * If the object is unlikely to grow don't allocate a reservation for 849 * the tail. 850 */ 851 if ((object->flags & OBJ_ANON) == 0 && 852 first + VM_LEVEL_0_NPAGES > object->size) 853 return (NULL); 854 855 /* 856 * Allocate and populate the new reservation. 857 */ 858 m = NULL; 859 vmd = VM_DOMAIN(domain); 860 if (vm_domain_allocate(vmd, req, 1)) { 861 vm_domain_free_lock(vmd); 862 m = vm_phys_alloc_pages(domain, VM_FREEPOOL_DEFAULT, 863 VM_LEVEL_0_ORDER); 864 vm_domain_free_unlock(vmd); 865 if (m == NULL) { 866 vm_domain_freecnt_inc(vmd, 1); 867 return (NULL); 868 } 869 } else 870 return (NULL); 871 rv = vm_reserv_from_page(m); 872 vm_reserv_lock(rv); 873 KASSERT(rv->pages == m, 874 ("vm_reserv_alloc_page: reserv %p's pages is corrupted", rv)); 875 vm_reserv_insert(rv, object, first); 876 index = VM_RESERV_INDEX(object, pindex); 877 vm_reserv_populate(rv, index); 878 vm_reserv_unlock(rv); 879 880 return (&rv->pages[index]); 881 } 882 883 /* 884 * Breaks the given reservation. All free pages in the reservation 885 * are returned to the physical memory allocator. The reservation's 886 * population count and map are reset to their initial state. 887 * 888 * The given reservation must not be in the partially populated reservation 889 * queue. 890 */ 891 static void 892 vm_reserv_break(vm_reserv_t rv) 893 { 894 int hi, lo, pos; 895 896 vm_reserv_assert_locked(rv); 897 CTR5(KTR_VM, "%s: rv %p object %p popcnt %d inpartpop %d", 898 __FUNCTION__, rv, rv->object, rv->popcnt, rv->inpartpopq); 899 vm_reserv_remove(rv); 900 rv->pages->psind = 0; 901 hi = lo = -1; 902 pos = 0; 903 for (;;) { 904 bit_ff_at(rv->popmap, pos, VM_LEVEL_0_NPAGES, lo != hi, &pos); 905 if (lo == hi) { 906 if (pos == -1) 907 break; 908 lo = pos; 909 continue; 910 } 911 if (pos == -1) 912 pos = VM_LEVEL_0_NPAGES; 913 hi = pos; 914 vm_domain_free_lock(VM_DOMAIN(rv->domain)); 915 vm_phys_enqueue_contig(&rv->pages[lo], hi - lo); 916 vm_domain_free_unlock(VM_DOMAIN(rv->domain)); 917 lo = hi; 918 } 919 bit_nclear(rv->popmap, 0, VM_LEVEL_0_NPAGES - 1); 920 rv->popcnt = 0; 921 counter_u64_add(vm_reserv_broken, 1); 922 } 923 924 /* 925 * Breaks all reservations belonging to the given object. 926 */ 927 void 928 vm_reserv_break_all(vm_object_t object) 929 { 930 vm_reserv_t rv; 931 932 /* 933 * This access of object->rvq is unsynchronized so that the 934 * object rvq lock can nest after the domain_free lock. We 935 * must check for races in the results. However, the object 936 * lock prevents new additions, so we are guaranteed that when 937 * it returns NULL the object is properly empty. 938 */ 939 while ((rv = LIST_FIRST(&object->rvq)) != NULL) { 940 vm_reserv_lock(rv); 941 /* Reclaim race. */ 942 if (rv->object != object) { 943 vm_reserv_unlock(rv); 944 continue; 945 } 946 vm_reserv_domain_lock(rv->domain); 947 if (rv->inpartpopq) { 948 TAILQ_REMOVE(&vm_rvd[rv->domain].partpop, rv, partpopq); 949 rv->inpartpopq = FALSE; 950 } 951 vm_reserv_domain_unlock(rv->domain); 952 vm_reserv_break(rv); 953 vm_reserv_unlock(rv); 954 } 955 } 956 957 /* 958 * Frees the given page if it belongs to a reservation. Returns TRUE if the 959 * page is freed and FALSE otherwise. 960 */ 961 boolean_t 962 vm_reserv_free_page(vm_page_t m) 963 { 964 vm_reserv_t rv; 965 boolean_t ret; 966 967 rv = vm_reserv_from_page(m); 968 if (rv->object == NULL) 969 return (FALSE); 970 vm_reserv_lock(rv); 971 /* Re-validate after lock. */ 972 if (rv->object != NULL) { 973 vm_reserv_depopulate(rv, m - rv->pages); 974 ret = TRUE; 975 } else 976 ret = FALSE; 977 vm_reserv_unlock(rv); 978 979 return (ret); 980 } 981 982 /* 983 * Initializes the reservation management system. Specifically, initializes 984 * the reservation array. 985 * 986 * Requires that vm_page_array and first_page are initialized! 987 */ 988 void 989 vm_reserv_init(void) 990 { 991 vm_paddr_t paddr; 992 struct vm_phys_seg *seg; 993 struct vm_reserv *rv; 994 struct vm_reserv_domain *rvd; 995 #ifdef VM_PHYSSEG_SPARSE 996 vm_pindex_t used; 997 #endif 998 int i, segind; 999 1000 /* 1001 * Initialize the reservation array. Specifically, initialize the 1002 * "pages" field for every element that has an underlying superpage. 1003 */ 1004 #ifdef VM_PHYSSEG_SPARSE 1005 used = 0; 1006 #endif 1007 for (segind = 0; segind < vm_phys_nsegs; segind++) { 1008 seg = &vm_phys_segs[segind]; 1009 #ifdef VM_PHYSSEG_SPARSE 1010 seg->first_reserv = &vm_reserv_array[used]; 1011 used += howmany(seg->end, VM_LEVEL_0_SIZE) - 1012 seg->start / VM_LEVEL_0_SIZE; 1013 #else 1014 seg->first_reserv = 1015 &vm_reserv_array[seg->start >> VM_LEVEL_0_SHIFT]; 1016 #endif 1017 paddr = roundup2(seg->start, VM_LEVEL_0_SIZE); 1018 rv = seg->first_reserv + (paddr >> VM_LEVEL_0_SHIFT) - 1019 (seg->start >> VM_LEVEL_0_SHIFT); 1020 while (paddr + VM_LEVEL_0_SIZE > paddr && paddr + 1021 VM_LEVEL_0_SIZE <= seg->end) { 1022 rv->pages = PHYS_TO_VM_PAGE(paddr); 1023 rv->domain = seg->domain; 1024 mtx_init(&rv->lock, "vm reserv", NULL, MTX_DEF); 1025 paddr += VM_LEVEL_0_SIZE; 1026 rv++; 1027 } 1028 } 1029 for (i = 0; i < MAXMEMDOM; i++) { 1030 rvd = &vm_rvd[i]; 1031 mtx_init(&rvd->lock, "vm reserv domain", NULL, MTX_DEF); 1032 TAILQ_INIT(&rvd->partpop); 1033 mtx_init(&rvd->marker.lock, "vm reserv marker", NULL, MTX_DEF); 1034 1035 /* 1036 * Fully populated reservations should never be present in the 1037 * partially populated reservation queues. 1038 */ 1039 rvd->marker.popcnt = VM_LEVEL_0_NPAGES; 1040 bit_nset(rvd->marker.popmap, 0, VM_LEVEL_0_NPAGES - 1); 1041 } 1042 1043 for (i = 0; i < VM_RESERV_OBJ_LOCK_COUNT; i++) 1044 mtx_init(&vm_reserv_object_mtx[i], "resv obj lock", NULL, 1045 MTX_DEF); 1046 } 1047 1048 /* 1049 * Returns true if the given page belongs to a reservation and that page is 1050 * free. Otherwise, returns false. 1051 */ 1052 bool 1053 vm_reserv_is_page_free(vm_page_t m) 1054 { 1055 vm_reserv_t rv; 1056 1057 rv = vm_reserv_from_page(m); 1058 if (rv->object == NULL) 1059 return (false); 1060 return (!bit_test(rv->popmap, m - rv->pages)); 1061 } 1062 1063 /* 1064 * If the given page belongs to a reservation, returns the level of that 1065 * reservation. Otherwise, returns -1. 1066 */ 1067 int 1068 vm_reserv_level(vm_page_t m) 1069 { 1070 vm_reserv_t rv; 1071 1072 rv = vm_reserv_from_page(m); 1073 return (rv->object != NULL ? 0 : -1); 1074 } 1075 1076 /* 1077 * Returns a reservation level if the given page belongs to a fully populated 1078 * reservation and -1 otherwise. 1079 */ 1080 int 1081 vm_reserv_level_iffullpop(vm_page_t m) 1082 { 1083 vm_reserv_t rv; 1084 1085 rv = vm_reserv_from_page(m); 1086 return (rv->popcnt == VM_LEVEL_0_NPAGES ? 0 : -1); 1087 } 1088 1089 /* 1090 * Remove a partially populated reservation from the queue. 1091 */ 1092 static void 1093 vm_reserv_dequeue(vm_reserv_t rv) 1094 { 1095 1096 vm_reserv_domain_assert_locked(rv->domain); 1097 vm_reserv_assert_locked(rv); 1098 CTR5(KTR_VM, "%s: rv %p object %p popcnt %d inpartpop %d", 1099 __FUNCTION__, rv, rv->object, rv->popcnt, rv->inpartpopq); 1100 KASSERT(rv->inpartpopq, 1101 ("vm_reserv_reclaim: reserv %p's inpartpopq is FALSE", rv)); 1102 1103 TAILQ_REMOVE(&vm_rvd[rv->domain].partpop, rv, partpopq); 1104 rv->inpartpopq = FALSE; 1105 } 1106 1107 /* 1108 * Breaks the given partially populated reservation, releasing its free pages 1109 * to the physical memory allocator. 1110 */ 1111 static void 1112 vm_reserv_reclaim(vm_reserv_t rv) 1113 { 1114 1115 vm_reserv_assert_locked(rv); 1116 CTR5(KTR_VM, "%s: rv %p object %p popcnt %d inpartpop %d", 1117 __FUNCTION__, rv, rv->object, rv->popcnt, rv->inpartpopq); 1118 if (rv->inpartpopq) { 1119 vm_reserv_domain_lock(rv->domain); 1120 vm_reserv_dequeue(rv); 1121 vm_reserv_domain_unlock(rv->domain); 1122 } 1123 vm_reserv_break(rv); 1124 counter_u64_add(vm_reserv_reclaimed, 1); 1125 } 1126 1127 /* 1128 * Breaks a reservation near the head of the partially populated reservation 1129 * queue, releasing its free pages to the physical memory allocator. Returns 1130 * TRUE if a reservation is broken and FALSE otherwise. 1131 */ 1132 bool 1133 vm_reserv_reclaim_inactive(int domain) 1134 { 1135 vm_reserv_t rv; 1136 1137 vm_reserv_domain_lock(domain); 1138 TAILQ_FOREACH(rv, &vm_rvd[domain].partpop, partpopq) { 1139 /* 1140 * A locked reservation is likely being updated or reclaimed, 1141 * so just skip ahead. 1142 */ 1143 if (rv != &vm_rvd[domain].marker && vm_reserv_trylock(rv)) { 1144 vm_reserv_dequeue(rv); 1145 break; 1146 } 1147 } 1148 vm_reserv_domain_unlock(domain); 1149 if (rv != NULL) { 1150 vm_reserv_reclaim(rv); 1151 vm_reserv_unlock(rv); 1152 return (true); 1153 } 1154 return (false); 1155 } 1156 1157 /* 1158 * Determine whether this reservation has free pages that satisfy the given 1159 * request for contiguous physical memory. Start searching from the lower 1160 * bound, defined by lo, and stop at the upper bound, hi. Return the index 1161 * of the first satisfactory free page, or -1 if none is found. 1162 */ 1163 static int 1164 vm_reserv_find_contig(vm_reserv_t rv, int npages, int lo, 1165 int hi, int ppn_align, int ppn_bound) 1166 { 1167 1168 vm_reserv_assert_locked(rv); 1169 KASSERT(npages <= VM_LEVEL_0_NPAGES - 1, 1170 ("%s: Too many pages", __func__)); 1171 KASSERT(ppn_bound <= VM_LEVEL_0_NPAGES, 1172 ("%s: Too big a boundary for reservation size", __func__)); 1173 KASSERT(npages <= ppn_bound, 1174 ("%s: Too many pages for given boundary", __func__)); 1175 KASSERT(ppn_align != 0 && powerof2(ppn_align), 1176 ("ppn_align is not a positive power of 2")); 1177 KASSERT(ppn_bound != 0 && powerof2(ppn_bound), 1178 ("ppn_bound is not a positive power of 2")); 1179 while (bit_ffc_area_at(rv->popmap, lo, hi, npages, &lo), lo != -1) { 1180 if (lo < roundup2(lo, ppn_align)) { 1181 /* Skip to next aligned page. */ 1182 lo = roundup2(lo, ppn_align); 1183 } else if (roundup2(lo + 1, ppn_bound) >= lo + npages) 1184 return (lo); 1185 if (roundup2(lo + 1, ppn_bound) < lo + npages) { 1186 /* Skip to next boundary-matching page. */ 1187 lo = roundup2(lo + 1, ppn_bound); 1188 } 1189 } 1190 return (-1); 1191 } 1192 1193 /* 1194 * Searches the partially populated reservation queue for the least recently 1195 * changed reservation with free pages that satisfy the given request for 1196 * contiguous physical memory. If a satisfactory reservation is found, it is 1197 * broken. Returns true if a reservation is broken and false otherwise. 1198 */ 1199 vm_page_t 1200 vm_reserv_reclaim_contig(int domain, u_long npages, vm_paddr_t low, 1201 vm_paddr_t high, u_long alignment, vm_paddr_t boundary) 1202 { 1203 struct vm_reserv_queue *queue; 1204 vm_paddr_t pa, size; 1205 vm_page_t m_ret; 1206 vm_reserv_t marker, rv, rvn; 1207 int hi, lo, posn, ppn_align, ppn_bound; 1208 1209 KASSERT(npages > 0, ("npages is 0")); 1210 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 1211 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 1212 if (npages > VM_LEVEL_0_NPAGES - 1) 1213 return (false); 1214 size = npages << PAGE_SHIFT; 1215 /* 1216 * Ensure that a free range starting at a boundary-multiple 1217 * doesn't include a boundary-multiple within it. Otherwise, 1218 * no boundary-constrained allocation is possible. 1219 */ 1220 if (!vm_addr_bound_ok(0, size, boundary)) 1221 return (NULL); 1222 marker = &vm_rvd[domain].marker; 1223 queue = &vm_rvd[domain].partpop; 1224 /* 1225 * Compute shifted alignment, boundary values for page-based 1226 * calculations. Constrain to range [1, VM_LEVEL_0_NPAGES] to 1227 * avoid overflow. 1228 */ 1229 ppn_align = (int)(ulmin(ulmax(PAGE_SIZE, alignment), 1230 VM_LEVEL_0_SIZE) >> PAGE_SHIFT); 1231 ppn_bound = boundary == 0 ? VM_LEVEL_0_NPAGES : 1232 (int)(MIN(MAX(PAGE_SIZE, boundary), 1233 VM_LEVEL_0_SIZE) >> PAGE_SHIFT); 1234 1235 vm_reserv_domain_scan_lock(domain); 1236 vm_reserv_domain_lock(domain); 1237 TAILQ_FOREACH_SAFE(rv, queue, partpopq, rvn) { 1238 pa = VM_PAGE_TO_PHYS(&rv->pages[0]); 1239 if (pa + VM_LEVEL_0_SIZE - size < low) { 1240 /* This entire reservation is too low; go to next. */ 1241 continue; 1242 } 1243 if (pa + size > high) { 1244 /* This entire reservation is too high; go to next. */ 1245 continue; 1246 } 1247 if (!vm_addr_align_ok(pa, alignment)) { 1248 /* This entire reservation is unaligned; go to next. */ 1249 continue; 1250 } 1251 1252 if (vm_reserv_trylock(rv) == 0) { 1253 TAILQ_INSERT_AFTER(queue, rv, marker, partpopq); 1254 vm_reserv_domain_unlock(domain); 1255 vm_reserv_lock(rv); 1256 if (TAILQ_PREV(marker, vm_reserv_queue, partpopq) != 1257 rv) { 1258 vm_reserv_unlock(rv); 1259 vm_reserv_domain_lock(domain); 1260 rvn = TAILQ_NEXT(marker, partpopq); 1261 TAILQ_REMOVE(queue, marker, partpopq); 1262 continue; 1263 } 1264 vm_reserv_domain_lock(domain); 1265 TAILQ_REMOVE(queue, marker, partpopq); 1266 } 1267 vm_reserv_domain_unlock(domain); 1268 lo = (pa >= low) ? 0 : 1269 (int)((low + PAGE_MASK - pa) >> PAGE_SHIFT); 1270 hi = (pa + VM_LEVEL_0_SIZE <= high) ? VM_LEVEL_0_NPAGES : 1271 (int)((high - pa) >> PAGE_SHIFT); 1272 posn = vm_reserv_find_contig(rv, (int)npages, lo, hi, 1273 ppn_align, ppn_bound); 1274 if (posn >= 0) { 1275 vm_reserv_domain_scan_unlock(domain); 1276 /* Allocate requested space */ 1277 rv->popcnt += npages; 1278 bit_nset(rv->popmap, posn, posn + npages - 1); 1279 vm_reserv_reclaim(rv); 1280 vm_reserv_unlock(rv); 1281 m_ret = &rv->pages[posn]; 1282 pa = VM_PAGE_TO_PHYS(m_ret); 1283 KASSERT(vm_addr_ok(pa, size, alignment, boundary), 1284 ("%s: adjusted address not aligned/bounded to " 1285 "%lx/%jx", 1286 __func__, alignment, (uintmax_t)boundary)); 1287 return (m_ret); 1288 } 1289 vm_reserv_domain_lock(domain); 1290 rvn = TAILQ_NEXT(rv, partpopq); 1291 vm_reserv_unlock(rv); 1292 } 1293 vm_reserv_domain_unlock(domain); 1294 vm_reserv_domain_scan_unlock(domain); 1295 return (NULL); 1296 } 1297 1298 /* 1299 * Transfers the reservation underlying the given page to a new object. 1300 * 1301 * The object must be locked. 1302 */ 1303 void 1304 vm_reserv_rename(vm_page_t m, vm_object_t new_object, vm_object_t old_object, 1305 vm_pindex_t old_object_offset) 1306 { 1307 vm_reserv_t rv; 1308 1309 VM_OBJECT_ASSERT_WLOCKED(new_object); 1310 rv = vm_reserv_from_page(m); 1311 if (rv->object == old_object) { 1312 vm_reserv_lock(rv); 1313 CTR6(KTR_VM, 1314 "%s: rv %p object %p new %p popcnt %d inpartpop %d", 1315 __FUNCTION__, rv, rv->object, new_object, rv->popcnt, 1316 rv->inpartpopq); 1317 if (rv->object == old_object) { 1318 vm_reserv_object_lock(old_object); 1319 rv->object = NULL; 1320 LIST_REMOVE(rv, objq); 1321 vm_reserv_object_unlock(old_object); 1322 vm_reserv_object_lock(new_object); 1323 rv->object = new_object; 1324 rv->pindex -= old_object_offset; 1325 LIST_INSERT_HEAD(&new_object->rvq, rv, objq); 1326 vm_reserv_object_unlock(new_object); 1327 } 1328 vm_reserv_unlock(rv); 1329 } 1330 } 1331 1332 /* 1333 * Returns the size (in bytes) of a reservation of the specified level. 1334 */ 1335 int 1336 vm_reserv_size(int level) 1337 { 1338 1339 switch (level) { 1340 case 0: 1341 return (VM_LEVEL_0_SIZE); 1342 case -1: 1343 return (PAGE_SIZE); 1344 default: 1345 return (0); 1346 } 1347 } 1348 1349 /* 1350 * Allocates the virtual and physical memory required by the reservation 1351 * management system's data structures, in particular, the reservation array. 1352 */ 1353 vm_paddr_t 1354 vm_reserv_startup(vm_offset_t *vaddr, vm_paddr_t end) 1355 { 1356 vm_paddr_t new_end; 1357 vm_pindex_t count; 1358 size_t size; 1359 int i; 1360 1361 count = 0; 1362 for (i = 0; i < vm_phys_nsegs; i++) { 1363 #ifdef VM_PHYSSEG_SPARSE 1364 count += howmany(vm_phys_segs[i].end, VM_LEVEL_0_SIZE) - 1365 vm_phys_segs[i].start / VM_LEVEL_0_SIZE; 1366 #else 1367 count = MAX(count, 1368 howmany(vm_phys_segs[i].end, VM_LEVEL_0_SIZE)); 1369 #endif 1370 } 1371 1372 for (i = 0; phys_avail[i + 1] != 0; i += 2) { 1373 #ifdef VM_PHYSSEG_SPARSE 1374 count += howmany(phys_avail[i + 1], VM_LEVEL_0_SIZE) - 1375 phys_avail[i] / VM_LEVEL_0_SIZE; 1376 #else 1377 count = MAX(count, 1378 howmany(phys_avail[i + 1], VM_LEVEL_0_SIZE)); 1379 #endif 1380 } 1381 1382 /* 1383 * Calculate the size (in bytes) of the reservation array. Rounding up 1384 * for partial superpages at boundaries, as every small page is mapped 1385 * to an element in the reservation array based on its physical address. 1386 * Thus, the number of elements in the reservation array can be greater 1387 * than the number of superpages. 1388 */ 1389 size = count * sizeof(struct vm_reserv); 1390 1391 /* 1392 * Allocate and map the physical memory for the reservation array. The 1393 * next available virtual address is returned by reference. 1394 */ 1395 new_end = end - round_page(size); 1396 vm_reserv_array = (void *)(uintptr_t)pmap_map(vaddr, new_end, end, 1397 VM_PROT_READ | VM_PROT_WRITE); 1398 bzero(vm_reserv_array, size); 1399 1400 /* 1401 * Return the next available physical address. 1402 */ 1403 return (new_end); 1404 } 1405 1406 /* 1407 * Returns the superpage containing the given page. 1408 */ 1409 vm_page_t 1410 vm_reserv_to_superpage(vm_page_t m) 1411 { 1412 vm_reserv_t rv; 1413 1414 VM_OBJECT_ASSERT_LOCKED(m->object); 1415 rv = vm_reserv_from_page(m); 1416 if (rv->object == m->object && rv->popcnt == VM_LEVEL_0_NPAGES) 1417 m = rv->pages; 1418 else 1419 m = NULL; 1420 1421 return (m); 1422 } 1423 1424 #endif /* VM_NRESERVLEVEL > 0 */
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