| 1 | /* |
| 2 | * Copyright (c) 1991 Regents of the University of California. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * This code is derived from software contributed to Berkeley by |
| 6 | * The Mach Operating System project at Carnegie-Mellon University. |
| 7 | * |
| 8 | * Redistribution and use in source and binary forms, with or without |
| 9 | * modification, are permitted provided that the following conditions |
| 10 | * are met: |
| 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 the |
| 15 | * documentation and/or other materials provided with the distribution. |
| 16 | * 3. All advertising materials mentioning features or use of this software |
| 17 | * must display the following acknowledgement: |
| 18 | * This product includes software developed by the University of |
| 19 | * California, Berkeley and its contributors. |
| 20 | * 4. Neither the name of the University nor the names of its contributors |
| 21 | * may be used to endorse or promote products derived from this software |
| 22 | * without specific prior written permission. |
| 23 | * |
| 24 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 25 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 26 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 27 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 28 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 29 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 30 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 31 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 32 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 33 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 34 | * SUCH DAMAGE. |
| 35 | * |
| 36 | * from: @(#)vm_page.c 7.4 (Berkeley) 5/7/91 |
| 37 | * $FreeBSD: src/sys/vm/vm_page.c,v 1.147.2.18 2002/03/10 05:03:19 alc Exp $ |
| 38 | * $DragonFly: src/sys/vm/vm_page.c,v 1.40 2008/08/25 17:01:42 dillon Exp $ |
| 39 | */ |
| 40 | |
| 41 | /* |
| 42 | * Copyright (c) 1987, 1990 Carnegie-Mellon University. |
| 43 | * All rights reserved. |
| 44 | * |
| 45 | * Authors: Avadis Tevanian, Jr., Michael Wayne Young |
| 46 | * |
| 47 | * Permission to use, copy, modify and distribute this software and |
| 48 | * its documentation is hereby granted, provided that both the copyright |
| 49 | * notice and this permission notice appear in all copies of the |
| 50 | * software, derivative works or modified versions, and any portions |
| 51 | * thereof, and that both notices appear in supporting documentation. |
| 52 | * |
| 53 | * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" |
| 54 | * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND |
| 55 | * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. |
| 56 | * |
| 57 | * Carnegie Mellon requests users of this software to return to |
| 58 | * |
| 59 | * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU |
| 60 | * School of Computer Science |
| 61 | * Carnegie Mellon University |
| 62 | * Pittsburgh PA 15213-3890 |
| 63 | * |
| 64 | * any improvements or extensions that they make and grant Carnegie the |
| 65 | * rights to redistribute these changes. |
| 66 | */ |
| 67 | /* |
| 68 | * Resident memory management module. The module manipulates 'VM pages'. |
| 69 | * A VM page is the core building block for memory management. |
| 70 | */ |
| 71 | |
| 72 | #include <sys/param.h> |
| 73 | #include <sys/systm.h> |
| 74 | #include <sys/malloc.h> |
| 75 | #include <sys/proc.h> |
| 76 | #include <sys/vmmeter.h> |
| 77 | #include <sys/vnode.h> |
| 78 | |
| 79 | #include <vm/vm.h> |
| 80 | #include <vm/vm_param.h> |
| 81 | #include <sys/lock.h> |
| 82 | #include <vm/vm_kern.h> |
| 83 | #include <vm/pmap.h> |
| 84 | #include <vm/vm_map.h> |
| 85 | #include <vm/vm_object.h> |
| 86 | #include <vm/vm_page.h> |
| 87 | #include <vm/vm_pageout.h> |
| 88 | #include <vm/vm_pager.h> |
| 89 | #include <vm/vm_extern.h> |
| 90 | #include <vm/vm_page2.h> |
| 91 | |
| 92 | static void vm_page_queue_init(void); |
| 93 | static void vm_page_free_wakeup(void); |
| 94 | static vm_page_t vm_page_select_cache(vm_object_t, vm_pindex_t); |
| 95 | static vm_page_t _vm_page_list_find2(int basequeue, int index); |
| 96 | |
| 97 | struct vpgqueues vm_page_queues[PQ_COUNT]; /* Array of tailq lists */ |
| 98 | |
| 99 | #define ASSERT_IN_CRIT_SECTION() KKASSERT(crit_test(curthread)); |
| 100 | |
| 101 | RB_GENERATE2(vm_page_rb_tree, vm_page, rb_entry, rb_vm_page_compare, |
| 102 | vm_pindex_t, pindex); |
| 103 | |
| 104 | static void |
| 105 | vm_page_queue_init(void) |
| 106 | { |
| 107 | int i; |
| 108 | |
| 109 | for (i = 0; i < PQ_L2_SIZE; i++) |
| 110 | vm_page_queues[PQ_FREE+i].cnt = &vmstats.v_free_count; |
| 111 | for (i = 0; i < PQ_L2_SIZE; i++) |
| 112 | vm_page_queues[PQ_CACHE+i].cnt = &vmstats.v_cache_count; |
| 113 | |
| 114 | vm_page_queues[PQ_INACTIVE].cnt = &vmstats.v_inactive_count; |
| 115 | vm_page_queues[PQ_ACTIVE].cnt = &vmstats.v_active_count; |
| 116 | vm_page_queues[PQ_HOLD].cnt = &vmstats.v_active_count; |
| 117 | /* PQ_NONE has no queue */ |
| 118 | |
| 119 | for (i = 0; i < PQ_COUNT; i++) |
| 120 | TAILQ_INIT(&vm_page_queues[i].pl); |
| 121 | } |
| 122 | |
| 123 | /* |
| 124 | * note: place in initialized data section? Is this necessary? |
| 125 | */ |
| 126 | long first_page = 0; |
| 127 | int vm_page_array_size = 0; |
| 128 | int vm_page_zero_count = 0; |
| 129 | vm_page_t vm_page_array = 0; |
| 130 | |
| 131 | /* |
| 132 | * (low level boot) |
| 133 | * |
| 134 | * Sets the page size, perhaps based upon the memory size. |
| 135 | * Must be called before any use of page-size dependent functions. |
| 136 | */ |
| 137 | void |
| 138 | vm_set_page_size(void) |
| 139 | { |
| 140 | if (vmstats.v_page_size == 0) |
| 141 | vmstats.v_page_size = PAGE_SIZE; |
| 142 | if (((vmstats.v_page_size - 1) & vmstats.v_page_size) != 0) |
| 143 | panic("vm_set_page_size: page size not a power of two"); |
| 144 | } |
| 145 | |
| 146 | /* |
| 147 | * (low level boot) |
| 148 | * |
| 149 | * Add a new page to the freelist for use by the system. New pages |
| 150 | * are added to both the head and tail of the associated free page |
| 151 | * queue in a bottom-up fashion, so both zero'd and non-zero'd page |
| 152 | * requests pull 'recent' adds (higher physical addresses) first. |
| 153 | * |
| 154 | * Must be called in a critical section. |
| 155 | */ |
| 156 | vm_page_t |
| 157 | vm_add_new_page(vm_paddr_t pa) |
| 158 | { |
| 159 | struct vpgqueues *vpq; |
| 160 | vm_page_t m; |
| 161 | |
| 162 | ++vmstats.v_page_count; |
| 163 | ++vmstats.v_free_count; |
| 164 | m = PHYS_TO_VM_PAGE(pa); |
| 165 | m->phys_addr = pa; |
| 166 | m->flags = 0; |
| 167 | m->pc = (pa >> PAGE_SHIFT) & PQ_L2_MASK; |
| 168 | m->queue = m->pc + PQ_FREE; |
| 169 | KKASSERT(m->dirty == 0); |
| 170 | |
| 171 | vpq = &vm_page_queues[m->queue]; |
| 172 | if (vpq->flipflop) |
| 173 | TAILQ_INSERT_TAIL(&vpq->pl, m, pageq); |
| 174 | else |
| 175 | TAILQ_INSERT_HEAD(&vpq->pl, m, pageq); |
| 176 | vpq->flipflop = 1 - vpq->flipflop; |
| 177 | |
| 178 | vm_page_queues[m->queue].lcnt++; |
| 179 | return (m); |
| 180 | } |
| 181 | |
| 182 | /* |
| 183 | * (low level boot) |
| 184 | * |
| 185 | * Initializes the resident memory module. |
| 186 | * |
| 187 | * Allocates memory for the page cells, and for the object/offset-to-page |
| 188 | * hash table headers. Each page cell is initialized and placed on the |
| 189 | * free list. |
| 190 | * |
| 191 | * starta/enda represents the range of physical memory addresses available |
| 192 | * for use (skipping memory already used by the kernel), subject to |
| 193 | * phys_avail[]. Note that phys_avail[] has already mapped out memory |
| 194 | * already in use by the kernel. |
| 195 | */ |
| 196 | vm_offset_t |
| 197 | vm_page_startup(vm_offset_t vaddr) |
| 198 | { |
| 199 | vm_offset_t mapped; |
| 200 | vm_size_t npages; |
| 201 | vm_paddr_t page_range; |
| 202 | vm_paddr_t new_end; |
| 203 | int i; |
| 204 | vm_paddr_t pa; |
| 205 | int nblocks; |
| 206 | vm_paddr_t last_pa; |
| 207 | vm_paddr_t end; |
| 208 | vm_paddr_t biggestone, biggestsize; |
| 209 | vm_paddr_t total; |
| 210 | |
| 211 | total = 0; |
| 212 | biggestsize = 0; |
| 213 | biggestone = 0; |
| 214 | nblocks = 0; |
| 215 | vaddr = round_page(vaddr); |
| 216 | |
| 217 | for (i = 0; phys_avail[i + 1]; i += 2) { |
| 218 | phys_avail[i] = round_page(phys_avail[i]); |
| 219 | phys_avail[i + 1] = trunc_page(phys_avail[i + 1]); |
| 220 | } |
| 221 | |
| 222 | for (i = 0; phys_avail[i + 1]; i += 2) { |
| 223 | vm_paddr_t size = phys_avail[i + 1] - phys_avail[i]; |
| 224 | |
| 225 | if (size > biggestsize) { |
| 226 | biggestone = i; |
| 227 | biggestsize = size; |
| 228 | } |
| 229 | ++nblocks; |
| 230 | total += size; |
| 231 | } |
| 232 | |
| 233 | end = phys_avail[biggestone+1]; |
| 234 | end = trunc_page(end); |
| 235 | |
| 236 | /* |
| 237 | * Initialize the queue headers for the free queue, the active queue |
| 238 | * and the inactive queue. |
| 239 | */ |
| 240 | |
| 241 | vm_page_queue_init(); |
| 242 | |
| 243 | /* |
| 244 | * Compute the number of pages of memory that will be available for |
| 245 | * use (taking into account the overhead of a page structure per |
| 246 | * page). |
| 247 | */ |
| 248 | first_page = phys_avail[0] / PAGE_SIZE; |
| 249 | page_range = phys_avail[(nblocks - 1) * 2 + 1] / PAGE_SIZE - first_page; |
| 250 | npages = (total - (page_range * sizeof(struct vm_page))) / PAGE_SIZE; |
| 251 | |
| 252 | /* |
| 253 | * Initialize the mem entry structures now, and put them in the free |
| 254 | * queue. |
| 255 | */ |
| 256 | vm_page_array = (vm_page_t) vaddr; |
| 257 | mapped = vaddr; |
| 258 | |
| 259 | /* |
| 260 | * Validate these addresses. |
| 261 | */ |
| 262 | new_end = trunc_page(end - page_range * sizeof(struct vm_page)); |
| 263 | mapped = pmap_map(mapped, new_end, end, |
| 264 | VM_PROT_READ | VM_PROT_WRITE); |
| 265 | |
| 266 | /* |
| 267 | * Clear all of the page structures |
| 268 | */ |
| 269 | bzero((caddr_t) vm_page_array, page_range * sizeof(struct vm_page)); |
| 270 | vm_page_array_size = page_range; |
| 271 | |
| 272 | /* |
| 273 | * Construct the free queue(s) in ascending order (by physical |
| 274 | * address) so that the first 16MB of physical memory is allocated |
| 275 | * last rather than first. On large-memory machines, this avoids |
| 276 | * the exhaustion of low physical memory before isa_dmainit has run. |
| 277 | */ |
| 278 | vmstats.v_page_count = 0; |
| 279 | vmstats.v_free_count = 0; |
| 280 | for (i = 0; phys_avail[i + 1] && npages > 0; i += 2) { |
| 281 | pa = phys_avail[i]; |
| 282 | if (i == biggestone) |
| 283 | last_pa = new_end; |
| 284 | else |
| 285 | last_pa = phys_avail[i + 1]; |
| 286 | while (pa < last_pa && npages-- > 0) { |
| 287 | vm_add_new_page(pa); |
| 288 | pa += PAGE_SIZE; |
| 289 | } |
| 290 | } |
| 291 | return (mapped); |
| 292 | } |
| 293 | |
| 294 | /* |
| 295 | * Scan comparison function for Red-Black tree scans. An inclusive |
| 296 | * (start,end) is expected. Other fields are not used. |
| 297 | */ |
| 298 | int |
| 299 | rb_vm_page_scancmp(struct vm_page *p, void *data) |
| 300 | { |
| 301 | struct rb_vm_page_scan_info *info = data; |
| 302 | |
| 303 | if (p->pindex < info->start_pindex) |
| 304 | return(-1); |
| 305 | if (p->pindex > info->end_pindex) |
| 306 | return(1); |
| 307 | return(0); |
| 308 | } |
| 309 | |
| 310 | int |
| 311 | rb_vm_page_compare(struct vm_page *p1, struct vm_page *p2) |
| 312 | { |
| 313 | if (p1->pindex < p2->pindex) |
| 314 | return(-1); |
| 315 | if (p1->pindex > p2->pindex) |
| 316 | return(1); |
| 317 | return(0); |
| 318 | } |
| 319 | |
| 320 | /* |
| 321 | * The opposite of vm_page_hold(). A page can be freed while being held, |
| 322 | * which places it on the PQ_HOLD queue. We must call vm_page_free_toq() |
| 323 | * in this case to actually free it once the hold count drops to 0. |
| 324 | * |
| 325 | * This routine must be called at splvm(). |
| 326 | */ |
| 327 | void |
| 328 | vm_page_unhold(vm_page_t mem) |
| 329 | { |
| 330 | --mem->hold_count; |
| 331 | KASSERT(mem->hold_count >= 0, ("vm_page_unhold: hold count < 0!!!")); |
| 332 | if (mem->hold_count == 0 && mem->queue == PQ_HOLD) { |
| 333 | vm_page_busy(mem); |
| 334 | vm_page_free_toq(mem); |
| 335 | } |
| 336 | } |
| 337 | |
| 338 | /* |
| 339 | * Inserts the given mem entry into the object and object list. |
| 340 | * |
| 341 | * The pagetables are not updated but will presumably fault the page |
| 342 | * in if necessary, or if a kernel page the caller will at some point |
| 343 | * enter the page into the kernel's pmap. We are not allowed to block |
| 344 | * here so we *can't* do this anyway. |
| 345 | * |
| 346 | * This routine may not block. |
| 347 | * This routine must be called with a critical section held. |
| 348 | */ |
| 349 | void |
| 350 | vm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex) |
| 351 | { |
| 352 | ASSERT_IN_CRIT_SECTION(); |
| 353 | if (m->object != NULL) |
| 354 | panic("vm_page_insert: already inserted"); |
| 355 | |
| 356 | /* |
| 357 | * Record the object/offset pair in this page |
| 358 | */ |
| 359 | m->object = object; |
| 360 | m->pindex = pindex; |
| 361 | |
| 362 | /* |
| 363 | * Insert it into the object. |
| 364 | */ |
| 365 | vm_page_rb_tree_RB_INSERT(&object->rb_memq, m); |
| 366 | object->generation++; |
| 367 | |
| 368 | /* |
| 369 | * show that the object has one more resident page. |
| 370 | */ |
| 371 | object->resident_page_count++; |
| 372 | |
| 373 | /* |
| 374 | * Since we are inserting a new and possibly dirty page, |
| 375 | * update the object's OBJ_WRITEABLE and OBJ_MIGHTBEDIRTY flags. |
| 376 | */ |
| 377 | if ((m->valid & m->dirty) || (m->flags & PG_WRITEABLE)) |
| 378 | vm_object_set_writeable_dirty(object); |
| 379 | } |
| 380 | |
| 381 | /* |
| 382 | * Removes the given vm_page_t from the global (object,index) hash table |
| 383 | * and from the object's memq. |
| 384 | * |
| 385 | * The underlying pmap entry (if any) is NOT removed here. |
| 386 | * This routine may not block. |
| 387 | * |
| 388 | * The page must be BUSY and will remain BUSY on return. No spl needs to be |
| 389 | * held on call to this routine. |
| 390 | * |
| 391 | * note: FreeBSD side effect was to unbusy the page on return. We leave |
| 392 | * it busy. |
| 393 | */ |
| 394 | void |
| 395 | vm_page_remove(vm_page_t m) |
| 396 | { |
| 397 | vm_object_t object; |
| 398 | |
| 399 | crit_enter(); |
| 400 | if (m->object == NULL) { |
| 401 | crit_exit(); |
| 402 | return; |
| 403 | } |
| 404 | |
| 405 | if ((m->flags & PG_BUSY) == 0) |
| 406 | panic("vm_page_remove: page not busy"); |
| 407 | |
| 408 | object = m->object; |
| 409 | |
| 410 | /* |
| 411 | * Remove the page from the object and update the object. |
| 412 | */ |
| 413 | vm_page_rb_tree_RB_REMOVE(&object->rb_memq, m); |
| 414 | object->resident_page_count--; |
| 415 | object->generation++; |
| 416 | m->object = NULL; |
| 417 | |
| 418 | crit_exit(); |
| 419 | } |
| 420 | |
| 421 | /* |
| 422 | * Locate and return the page at (object, pindex), or NULL if the |
| 423 | * page could not be found. |
| 424 | * |
| 425 | * This routine will operate properly without spl protection, but |
| 426 | * the returned page could be in flux if it is busy. Because an |
| 427 | * interrupt can race a caller's busy check (unbusying and freeing the |
| 428 | * page we return before the caller is able to check the busy bit), |
| 429 | * the caller should generally call this routine with a critical |
| 430 | * section held. |
| 431 | * |
| 432 | * Callers may call this routine without spl protection if they know |
| 433 | * 'for sure' that the page will not be ripped out from under them |
| 434 | * by an interrupt. |
| 435 | */ |
| 436 | vm_page_t |
| 437 | vm_page_lookup(vm_object_t object, vm_pindex_t pindex) |
| 438 | { |
| 439 | vm_page_t m; |
| 440 | |
| 441 | /* |
| 442 | * Search the hash table for this object/offset pair |
| 443 | */ |
| 444 | crit_enter(); |
| 445 | m = vm_page_rb_tree_RB_LOOKUP(&object->rb_memq, pindex); |
| 446 | crit_exit(); |
| 447 | KKASSERT(m == NULL || (m->object == object && m->pindex == pindex)); |
| 448 | return(m); |
| 449 | } |
| 450 | |
| 451 | /* |
| 452 | * vm_page_rename() |
| 453 | * |
| 454 | * Move the given memory entry from its current object to the specified |
| 455 | * target object/offset. |
| 456 | * |
| 457 | * The object must be locked. |
| 458 | * This routine may not block. |
| 459 | * |
| 460 | * Note: This routine will raise itself to splvm(), the caller need not. |
| 461 | * |
| 462 | * Note: Swap associated with the page must be invalidated by the move. We |
| 463 | * have to do this for several reasons: (1) we aren't freeing the |
| 464 | * page, (2) we are dirtying the page, (3) the VM system is probably |
| 465 | * moving the page from object A to B, and will then later move |
| 466 | * the backing store from A to B and we can't have a conflict. |
| 467 | * |
| 468 | * Note: We *always* dirty the page. It is necessary both for the |
| 469 | * fact that we moved it, and because we may be invalidating |
| 470 | * swap. If the page is on the cache, we have to deactivate it |
| 471 | * or vm_page_dirty() will panic. Dirty pages are not allowed |
| 472 | * on the cache. |
| 473 | */ |
| 474 | void |
| 475 | vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex) |
| 476 | { |
| 477 | crit_enter(); |
| 478 | vm_page_remove(m); |
| 479 | vm_page_insert(m, new_object, new_pindex); |
| 480 | if (m->queue - m->pc == PQ_CACHE) |
| 481 | vm_page_deactivate(m); |
| 482 | vm_page_dirty(m); |
| 483 | vm_page_wakeup(m); |
| 484 | crit_exit(); |
| 485 | } |
| 486 | |
| 487 | /* |
| 488 | * vm_page_unqueue() without any wakeup. This routine is used when a page |
| 489 | * is being moved between queues or otherwise is to remain BUSYied by the |
| 490 | * caller. |
| 491 | * |
| 492 | * This routine must be called at splhigh(). |
| 493 | * This routine may not block. |
| 494 | */ |
| 495 | void |
| 496 | vm_page_unqueue_nowakeup(vm_page_t m) |
| 497 | { |
| 498 | int queue = m->queue; |
| 499 | struct vpgqueues *pq; |
| 500 | |
| 501 | if (queue != PQ_NONE) { |
| 502 | pq = &vm_page_queues[queue]; |
| 503 | m->queue = PQ_NONE; |
| 504 | TAILQ_REMOVE(&pq->pl, m, pageq); |
| 505 | (*pq->cnt)--; |
| 506 | pq->lcnt--; |
| 507 | } |
| 508 | } |
| 509 | |
| 510 | /* |
| 511 | * vm_page_unqueue() - Remove a page from its queue, wakeup the pagedemon |
| 512 | * if necessary. |
| 513 | * |
| 514 | * This routine must be called at splhigh(). |
| 515 | * This routine may not block. |
| 516 | */ |
| 517 | void |
| 518 | vm_page_unqueue(vm_page_t m) |
| 519 | { |
| 520 | int queue = m->queue; |
| 521 | struct vpgqueues *pq; |
| 522 | |
| 523 | if (queue != PQ_NONE) { |
| 524 | m->queue = PQ_NONE; |
| 525 | pq = &vm_page_queues[queue]; |
| 526 | TAILQ_REMOVE(&pq->pl, m, pageq); |
| 527 | (*pq->cnt)--; |
| 528 | pq->lcnt--; |
| 529 | if ((queue - m->pc) == PQ_CACHE || (queue - m->pc) == PQ_FREE) |
| 530 | pagedaemon_wakeup(); |
| 531 | } |
| 532 | } |
| 533 | |
| 534 | /* |
| 535 | * vm_page_list_find() |
| 536 | * |
| 537 | * Find a page on the specified queue with color optimization. |
| 538 | * |
| 539 | * The page coloring optimization attempts to locate a page that does |
| 540 | * not overload other nearby pages in the object in the cpu's L1 or L2 |
| 541 | * caches. We need this optimization because cpu caches tend to be |
| 542 | * physical caches, while object spaces tend to be virtual. |
| 543 | * |
| 544 | * This routine must be called at splvm(). |
| 545 | * This routine may not block. |
| 546 | * |
| 547 | * Note that this routine is carefully inlined. A non-inlined version |
| 548 | * is available for outside callers but the only critical path is |
| 549 | * from within this source file. |
| 550 | */ |
| 551 | static __inline |
| 552 | vm_page_t |
| 553 | _vm_page_list_find(int basequeue, int index, boolean_t prefer_zero) |
| 554 | { |
| 555 | vm_page_t m; |
| 556 | |
| 557 | if (prefer_zero) |
| 558 | m = TAILQ_LAST(&vm_page_queues[basequeue+index].pl, pglist); |
| 559 | else |
| 560 | m = TAILQ_FIRST(&vm_page_queues[basequeue+index].pl); |
| 561 | if (m == NULL) |
| 562 | m = _vm_page_list_find2(basequeue, index); |
| 563 | return(m); |
| 564 | } |
| 565 | |
| 566 | static vm_page_t |
| 567 | _vm_page_list_find2(int basequeue, int index) |
| 568 | { |
| 569 | int i; |
| 570 | vm_page_t m = NULL; |
| 571 | struct vpgqueues *pq; |
| 572 | |
| 573 | pq = &vm_page_queues[basequeue]; |
| 574 | |
| 575 | /* |
| 576 | * Note that for the first loop, index+i and index-i wind up at the |
| 577 | * same place. Even though this is not totally optimal, we've already |
| 578 | * blown it by missing the cache case so we do not care. |
| 579 | */ |
| 580 | |
| 581 | for(i = PQ_L2_SIZE / 2; i > 0; --i) { |
| 582 | if ((m = TAILQ_FIRST(&pq[(index + i) & PQ_L2_MASK].pl)) != NULL) |
| 583 | break; |
| 584 | |
| 585 | if ((m = TAILQ_FIRST(&pq[(index - i) & PQ_L2_MASK].pl)) != NULL) |
| 586 | break; |
| 587 | } |
| 588 | return(m); |
| 589 | } |
| 590 | |
| 591 | vm_page_t |
| 592 | vm_page_list_find(int basequeue, int index, boolean_t prefer_zero) |
| 593 | { |
| 594 | return(_vm_page_list_find(basequeue, index, prefer_zero)); |
| 595 | } |
| 596 | |
| 597 | /* |
| 598 | * Find a page on the cache queue with color optimization. As pages |
| 599 | * might be found, but not applicable, they are deactivated. This |
| 600 | * keeps us from using potentially busy cached pages. |
| 601 | * |
| 602 | * This routine must be called with a critical section held. |
| 603 | * This routine may not block. |
| 604 | */ |
| 605 | vm_page_t |
| 606 | vm_page_select_cache(vm_object_t object, vm_pindex_t pindex) |
| 607 | { |
| 608 | vm_page_t m; |
| 609 | |
| 610 | while (TRUE) { |
| 611 | m = _vm_page_list_find( |
| 612 | PQ_CACHE, |
| 613 | (pindex + object->pg_color) & PQ_L2_MASK, |
| 614 | FALSE |
| 615 | ); |
| 616 | if (m && ((m->flags & (PG_BUSY|PG_UNMANAGED)) || m->busy || |
| 617 | m->hold_count || m->wire_count)) { |
| 618 | vm_page_deactivate(m); |
| 619 | continue; |
| 620 | } |
| 621 | return m; |
| 622 | } |
| 623 | /* not reached */ |
| 624 | } |
| 625 | |
| 626 | /* |
| 627 | * Find a free or zero page, with specified preference. We attempt to |
| 628 | * inline the nominal case and fall back to _vm_page_select_free() |
| 629 | * otherwise. |
| 630 | * |
| 631 | * This routine must be called with a critical section held. |
| 632 | * This routine may not block. |
| 633 | */ |
| 634 | static __inline vm_page_t |
| 635 | vm_page_select_free(vm_object_t object, vm_pindex_t pindex, boolean_t prefer_zero) |
| 636 | { |
| 637 | vm_page_t m; |
| 638 | |
| 639 | m = _vm_page_list_find( |
| 640 | PQ_FREE, |
| 641 | (pindex + object->pg_color) & PQ_L2_MASK, |
| 642 | prefer_zero |
| 643 | ); |
| 644 | return(m); |
| 645 | } |
| 646 | |
| 647 | /* |
| 648 | * vm_page_alloc() |
| 649 | * |
| 650 | * Allocate and return a memory cell associated with this VM object/offset |
| 651 | * pair. |
| 652 | * |
| 653 | * page_req classes: |
| 654 | * |
| 655 | * VM_ALLOC_NORMAL allow use of cache pages, nominal free drain |
| 656 | * VM_ALLOC_SYSTEM greater free drain |
| 657 | * VM_ALLOC_INTERRUPT allow free list to be completely drained |
| 658 | * VM_ALLOC_ZERO advisory request for pre-zero'd page |
| 659 | * |
| 660 | * The object must be locked. |
| 661 | * This routine may not block. |
| 662 | * The returned page will be marked PG_BUSY |
| 663 | * |
| 664 | * Additional special handling is required when called from an interrupt |
| 665 | * (VM_ALLOC_INTERRUPT). We are not allowed to mess with the page cache |
| 666 | * in this case. |
| 667 | */ |
| 668 | vm_page_t |
| 669 | vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int page_req) |
| 670 | { |
| 671 | vm_page_t m = NULL; |
| 672 | |
| 673 | KKASSERT(object != NULL); |
| 674 | KASSERT(!vm_page_lookup(object, pindex), |
| 675 | ("vm_page_alloc: page already allocated")); |
| 676 | KKASSERT(page_req & |
| 677 | (VM_ALLOC_NORMAL|VM_ALLOC_INTERRUPT|VM_ALLOC_SYSTEM)); |
| 678 | |
| 679 | /* |
| 680 | * Certain system threads (pageout daemon, buf_daemon's) are |
| 681 | * allowed to eat deeper into the free page list. |
| 682 | */ |
| 683 | if (curthread->td_flags & TDF_SYSTHREAD) |
| 684 | page_req |= VM_ALLOC_SYSTEM; |
| 685 | |
| 686 | crit_enter(); |
| 687 | loop: |
| 688 | if (vmstats.v_free_count > vmstats.v_free_reserved || |
| 689 | ((page_req & VM_ALLOC_INTERRUPT) && vmstats.v_free_count > 0) || |
| 690 | ((page_req & VM_ALLOC_SYSTEM) && vmstats.v_cache_count == 0 && |
| 691 | vmstats.v_free_count > vmstats.v_interrupt_free_min) |
| 692 | ) { |
| 693 | /* |
| 694 | * The free queue has sufficient free pages to take one out. |
| 695 | */ |
| 696 | if (page_req & VM_ALLOC_ZERO) |
| 697 | m = vm_page_select_free(object, pindex, TRUE); |
| 698 | else |
| 699 | m = vm_page_select_free(object, pindex, FALSE); |
| 700 | } else if (page_req & VM_ALLOC_NORMAL) { |
| 701 | /* |
| 702 | * Allocatable from the cache (non-interrupt only). On |
| 703 | * success, we must free the page and try again, thus |
| 704 | * ensuring that vmstats.v_*_free_min counters are replenished. |
| 705 | */ |
| 706 | #ifdef INVARIANTS |
| 707 | if (curthread->td_preempted) { |
| 708 | kprintf("vm_page_alloc(): warning, attempt to allocate" |
| 709 | " cache page from preempting interrupt\n"); |
| 710 | m = NULL; |
| 711 | } else { |
| 712 | m = vm_page_select_cache(object, pindex); |
| 713 | } |
| 714 | #else |
| 715 | m = vm_page_select_cache(object, pindex); |
| 716 | #endif |
| 717 | /* |
| 718 | * On success move the page into the free queue and loop. |
| 719 | */ |
| 720 | if (m != NULL) { |
| 721 | KASSERT(m->dirty == 0, |
| 722 | ("Found dirty cache page %p", m)); |
| 723 | vm_page_busy(m); |
| 724 | vm_page_protect(m, VM_PROT_NONE); |
| 725 | vm_page_free(m); |
| 726 | goto loop; |
| 727 | } |
| 728 | |
| 729 | /* |
| 730 | * On failure return NULL |
| 731 | */ |
| 732 | crit_exit(); |
| 733 | #if defined(DIAGNOSTIC) |
| 734 | if (vmstats.v_cache_count > 0) |
| 735 | kprintf("vm_page_alloc(NORMAL): missing pages on cache queue: %d\n", vmstats.v_cache_count); |
| 736 | #endif |
| 737 | vm_pageout_deficit++; |
| 738 | pagedaemon_wakeup(); |
| 739 | return (NULL); |
| 740 | } else { |
| 741 | /* |
| 742 | * No pages available, wakeup the pageout daemon and give up. |
| 743 | */ |
| 744 | crit_exit(); |
| 745 | vm_pageout_deficit++; |
| 746 | pagedaemon_wakeup(); |
| 747 | return (NULL); |
| 748 | } |
| 749 | |
| 750 | /* |
| 751 | * Good page found. The page has not yet been busied. We are in |
| 752 | * a critical section. |
| 753 | */ |
| 754 | KASSERT(m != NULL, ("vm_page_alloc(): missing page on free queue\n")); |
| 755 | KASSERT(m->dirty == 0, |
| 756 | ("vm_page_alloc: free/cache page %p was dirty", m)); |
| 757 | |
| 758 | /* |
| 759 | * Remove from free queue |
| 760 | */ |
| 761 | vm_page_unqueue_nowakeup(m); |
| 762 | |
| 763 | /* |
| 764 | * Initialize structure. Only the PG_ZERO flag is inherited. Set |
| 765 | * the page PG_BUSY |
| 766 | */ |
| 767 | if (m->flags & PG_ZERO) { |
| 768 | vm_page_zero_count--; |
| 769 | m->flags = PG_ZERO | PG_BUSY; |
| 770 | } else { |
| 771 | m->flags = PG_BUSY; |
| 772 | } |
| 773 | m->wire_count = 0; |
| 774 | m->hold_count = 0; |
| 775 | m->act_count = 0; |
| 776 | m->busy = 0; |
| 777 | m->valid = 0; |
| 778 | |
| 779 | /* |
| 780 | * vm_page_insert() is safe prior to the crit_exit(). Note also that |
| 781 | * inserting a page here does not insert it into the pmap (which |
| 782 | * could cause us to block allocating memory). We cannot block |
| 783 | * anywhere. |
| 784 | */ |
| 785 | vm_page_insert(m, object, pindex); |
| 786 | |
| 787 | /* |
| 788 | * Don't wakeup too often - wakeup the pageout daemon when |
| 789 | * we would be nearly out of memory. |
| 790 | */ |
| 791 | pagedaemon_wakeup(); |
| 792 | |
| 793 | crit_exit(); |
| 794 | |
| 795 | /* |
| 796 | * A PG_BUSY page is returned. |
| 797 | */ |
| 798 | return (m); |
| 799 | } |
| 800 | |
| 801 | /* |
| 802 | * Block until free pages are available for allocation, called in various |
| 803 | * places before memory allocations. |
| 804 | */ |
| 805 | void |
| 806 | vm_wait(int timo) |
| 807 | { |
| 808 | crit_enter(); |
| 809 | if (curthread == pagethread) { |
| 810 | vm_pageout_pages_needed = 1; |
| 811 | tsleep(&vm_pageout_pages_needed, 0, "VMWait", timo); |
| 812 | } else { |
| 813 | if (vm_pages_needed == 0) { |
| 814 | vm_pages_needed = 1; |
| 815 | wakeup(&vm_pages_needed); |
| 816 | } |
| 817 | tsleep(&vmstats.v_free_count, 0, "vmwait", timo); |
| 818 | } |
| 819 | crit_exit(); |
| 820 | } |
| 821 | |
| 822 | /* |
| 823 | * Block until free pages are available for allocation |
| 824 | * |
| 825 | * Called only in vm_fault so that processes page faulting can be |
| 826 | * easily tracked. |
| 827 | */ |
| 828 | void |
| 829 | vm_waitpfault(void) |
| 830 | { |
| 831 | crit_enter(); |
| 832 | if (vm_pages_needed == 0) { |
| 833 | vm_pages_needed = 1; |
| 834 | wakeup(&vm_pages_needed); |
| 835 | } |
| 836 | tsleep(&vmstats.v_free_count, 0, "pfault", 0); |
| 837 | crit_exit(); |
| 838 | } |
| 839 | |
| 840 | /* |
| 841 | * Put the specified page on the active list (if appropriate). Ensure |
| 842 | * that act_count is at least ACT_INIT but do not otherwise mess with it. |
| 843 | * |
| 844 | * The page queues must be locked. |
| 845 | * This routine may not block. |
| 846 | */ |
| 847 | void |
| 848 | vm_page_activate(vm_page_t m) |
| 849 | { |
| 850 | crit_enter(); |
| 851 | if (m->queue != PQ_ACTIVE) { |
| 852 | if ((m->queue - m->pc) == PQ_CACHE) |
| 853 | mycpu->gd_cnt.v_reactivated++; |
| 854 | |
| 855 | vm_page_unqueue(m); |
| 856 | |
| 857 | if (m->wire_count == 0 && (m->flags & PG_UNMANAGED) == 0) { |
| 858 | m->queue = PQ_ACTIVE; |
| 859 | vm_page_queues[PQ_ACTIVE].lcnt++; |
| 860 | TAILQ_INSERT_TAIL(&vm_page_queues[PQ_ACTIVE].pl, |
| 861 | m, pageq); |
| 862 | if (m->act_count < ACT_INIT) |
| 863 | m->act_count = ACT_INIT; |
| 864 | vmstats.v_active_count++; |
| 865 | } |
| 866 | } else { |
| 867 | if (m->act_count < ACT_INIT) |
| 868 | m->act_count = ACT_INIT; |
| 869 | } |
| 870 | crit_exit(); |
| 871 | } |
| 872 | |
| 873 | /* |
| 874 | * Helper routine for vm_page_free_toq() and vm_page_cache(). This |
| 875 | * routine is called when a page has been added to the cache or free |
| 876 | * queues. |
| 877 | * |
| 878 | * This routine may not block. |
| 879 | * This routine must be called at splvm() |
| 880 | */ |
| 881 | static __inline void |
| 882 | vm_page_free_wakeup(void) |
| 883 | { |
| 884 | /* |
| 885 | * if pageout daemon needs pages, then tell it that there are |
| 886 | * some free. |
| 887 | */ |
| 888 | if (vm_pageout_pages_needed && |
| 889 | vmstats.v_cache_count + vmstats.v_free_count >= |
| 890 | vmstats.v_pageout_free_min |
| 891 | ) { |
| 892 | wakeup(&vm_pageout_pages_needed); |
| 893 | vm_pageout_pages_needed = 0; |
| 894 | } |
| 895 | |
| 896 | /* |
| 897 | * wakeup processes that are waiting on memory if we hit a |
| 898 | * high water mark. And wakeup scheduler process if we have |
| 899 | * lots of memory. this process will swapin processes. |
| 900 | */ |
| 901 | if (vm_pages_needed && !vm_page_count_min(0)) { |
| 902 | vm_pages_needed = 0; |
| 903 | wakeup(&vmstats.v_free_count); |
| 904 | } |
| 905 | } |
| 906 | |
| 907 | /* |
| 908 | * vm_page_free_toq: |
| 909 | * |
| 910 | * Returns the given page to the PQ_FREE list, disassociating it with |
| 911 | * any VM object. |
| 912 | * |
| 913 | * The vm_page must be PG_BUSY on entry. PG_BUSY will be released on |
| 914 | * return (the page will have been freed). No particular spl is required |
| 915 | * on entry. |
| 916 | * |
| 917 | * This routine may not block. |
| 918 | */ |
| 919 | void |
| 920 | vm_page_free_toq(vm_page_t m) |
| 921 | { |
| 922 | struct vpgqueues *pq; |
| 923 | |
| 924 | crit_enter(); |
| 925 | mycpu->gd_cnt.v_tfree++; |
| 926 | |
| 927 | KKASSERT((m->flags & PG_MAPPED) == 0); |
| 928 | |
| 929 | if (m->busy || ((m->queue - m->pc) == PQ_FREE)) { |
| 930 | kprintf( |
| 931 | "vm_page_free: pindex(%lu), busy(%d), PG_BUSY(%d), hold(%d)\n", |
| 932 | (u_long)m->pindex, m->busy, (m->flags & PG_BUSY) ? 1 : 0, |
| 933 | m->hold_count); |
| 934 | if ((m->queue - m->pc) == PQ_FREE) |
| 935 | panic("vm_page_free: freeing free page"); |
| 936 | else |
| 937 | panic("vm_page_free: freeing busy page"); |
| 938 | } |
| 939 | |
| 940 | /* |
| 941 | * unqueue, then remove page. Note that we cannot destroy |
| 942 | * the page here because we do not want to call the pager's |
| 943 | * callback routine until after we've put the page on the |
| 944 | * appropriate free queue. |
| 945 | */ |
| 946 | vm_page_unqueue_nowakeup(m); |
| 947 | vm_page_remove(m); |
| 948 | |
| 949 | /* |
| 950 | * No further management of fictitious pages occurs beyond object |
| 951 | * and queue removal. |
| 952 | */ |
| 953 | if ((m->flags & PG_FICTITIOUS) != 0) { |
| 954 | vm_page_wakeup(m); |
| 955 | crit_exit(); |
| 956 | return; |
| 957 | } |
| 958 | |
| 959 | m->valid = 0; |
| 960 | vm_page_undirty(m); |
| 961 | |
| 962 | if (m->wire_count != 0) { |
| 963 | if (m->wire_count > 1) { |
| 964 | panic( |
| 965 | "vm_page_free: invalid wire count (%d), pindex: 0x%lx", |
| 966 | m->wire_count, (long)m->pindex); |
| 967 | } |
| 968 | panic("vm_page_free: freeing wired page"); |
| 969 | } |
| 970 | |
| 971 | /* |
| 972 | * Clear the UNMANAGED flag when freeing an unmanaged page. |
| 973 | */ |
| 974 | if (m->flags & PG_UNMANAGED) { |
| 975 | m->flags &= ~PG_UNMANAGED; |
| 976 | } |
| 977 | |
| 978 | if (m->hold_count != 0) { |
| 979 | m->flags &= ~PG_ZERO; |
| 980 | m->queue = PQ_HOLD; |
| 981 | } else { |
| 982 | m->queue = PQ_FREE + m->pc; |
| 983 | } |
| 984 | pq = &vm_page_queues[m->queue]; |
| 985 | pq->lcnt++; |
| 986 | ++(*pq->cnt); |
| 987 | |
| 988 | /* |
| 989 | * Put zero'd pages on the end ( where we look for zero'd pages |
| 990 | * first ) and non-zerod pages at the head. |
| 991 | */ |
| 992 | if (m->flags & PG_ZERO) { |
| 993 | TAILQ_INSERT_TAIL(&pq->pl, m, pageq); |
| 994 | ++vm_page_zero_count; |
| 995 | } else { |
| 996 | TAILQ_INSERT_HEAD(&pq->pl, m, pageq); |
| 997 | } |
| 998 | vm_page_wakeup(m); |
| 999 | vm_page_free_wakeup(); |
| 1000 | crit_exit(); |
| 1001 | } |
| 1002 | |
| 1003 | /* |
| 1004 | * vm_page_unmanage() |
| 1005 | * |
| 1006 | * Prevent PV management from being done on the page. The page is |
| 1007 | * removed from the paging queues as if it were wired, and as a |
| 1008 | * consequence of no longer being managed the pageout daemon will not |
| 1009 | * touch it (since there is no way to locate the pte mappings for the |
| 1010 | * page). madvise() calls that mess with the pmap will also no longer |
| 1011 | * operate on the page. |
| 1012 | * |
| 1013 | * Beyond that the page is still reasonably 'normal'. Freeing the page |
| 1014 | * will clear the flag. |
| 1015 | * |
| 1016 | * This routine is used by OBJT_PHYS objects - objects using unswappable |
| 1017 | * physical memory as backing store rather then swap-backed memory and |
| 1018 | * will eventually be extended to support 4MB unmanaged physical |
| 1019 | * mappings. |
| 1020 | * |
| 1021 | * Must be called with a critical section held. |
| 1022 | */ |
| 1023 | void |
| 1024 | vm_page_unmanage(vm_page_t m) |
| 1025 | { |
| 1026 | ASSERT_IN_CRIT_SECTION(); |
| 1027 | if ((m->flags & PG_UNMANAGED) == 0) { |
| 1028 | if (m->wire_count == 0) |
| 1029 | vm_page_unqueue(m); |
| 1030 | } |
| 1031 | vm_page_flag_set(m, PG_UNMANAGED); |
| 1032 | } |
| 1033 | |
| 1034 | /* |
| 1035 | * Mark this page as wired down by yet another map, removing it from |
| 1036 | * paging queues as necessary. |
| 1037 | * |
| 1038 | * The page queues must be locked. |
| 1039 | * This routine may not block. |
| 1040 | */ |
| 1041 | void |
| 1042 | vm_page_wire(vm_page_t m) |
| 1043 | { |
| 1044 | /* |
| 1045 | * Only bump the wire statistics if the page is not already wired, |
| 1046 | * and only unqueue the page if it is on some queue (if it is unmanaged |
| 1047 | * it is already off the queues). Don't do anything with fictitious |
| 1048 | * pages because they are always wired. |
| 1049 | */ |
| 1050 | crit_enter(); |
| 1051 | if ((m->flags & PG_FICTITIOUS) == 0) { |
| 1052 | if (m->wire_count == 0) { |
| 1053 | if ((m->flags & PG_UNMANAGED) == 0) |
| 1054 | vm_page_unqueue(m); |
| 1055 | vmstats.v_wire_count++; |
| 1056 | } |
| 1057 | m->wire_count++; |
| 1058 | KASSERT(m->wire_count != 0, |
| 1059 | ("vm_page_wire: wire_count overflow m=%p", m)); |
| 1060 | } |
| 1061 | crit_exit(); |
| 1062 | } |
| 1063 | |
| 1064 | /* |
| 1065 | * Release one wiring of this page, potentially enabling it to be paged again. |
| 1066 | * |
| 1067 | * Many pages placed on the inactive queue should actually go |
| 1068 | * into the cache, but it is difficult to figure out which. What |
| 1069 | * we do instead, if the inactive target is well met, is to put |
| 1070 | * clean pages at the head of the inactive queue instead of the tail. |
| 1071 | * This will cause them to be moved to the cache more quickly and |
| 1072 | * if not actively re-referenced, freed more quickly. If we just |
| 1073 | * stick these pages at the end of the inactive queue, heavy filesystem |
| 1074 | * meta-data accesses can cause an unnecessary paging load on memory bound |
| 1075 | * processes. This optimization causes one-time-use metadata to be |
| 1076 | * reused more quickly. |
| 1077 | * |
| 1078 | * BUT, if we are in a low-memory situation we have no choice but to |
| 1079 | * put clean pages on the cache queue. |
| 1080 | * |
| 1081 | * A number of routines use vm_page_unwire() to guarantee that the page |
| 1082 | * will go into either the inactive or active queues, and will NEVER |
| 1083 | * be placed in the cache - for example, just after dirtying a page. |
| 1084 | * dirty pages in the cache are not allowed. |
| 1085 | * |
| 1086 | * The page queues must be locked. |
| 1087 | * This routine may not block. |
| 1088 | */ |
| 1089 | void |
| 1090 | vm_page_unwire(vm_page_t m, int activate) |
| 1091 | { |
| 1092 | crit_enter(); |
| 1093 | if (m->flags & PG_FICTITIOUS) { |
| 1094 | /* do nothing */ |
| 1095 | } else if (m->wire_count <= 0) { |
| 1096 | panic("vm_page_unwire: invalid wire count: %d", m->wire_count); |
| 1097 | } else { |
| 1098 | if (--m->wire_count == 0) { |
| 1099 | --vmstats.v_wire_count; |
| 1100 | if (m->flags & PG_UNMANAGED) { |
| 1101 | ; |
| 1102 | } else if (activate) { |
| 1103 | TAILQ_INSERT_TAIL( |
| 1104 | &vm_page_queues[PQ_ACTIVE].pl, m, pageq); |
| 1105 | m->queue = PQ_ACTIVE; |
| 1106 | vm_page_queues[PQ_ACTIVE].lcnt++; |
| 1107 | vmstats.v_active_count++; |
| 1108 | } else { |
| 1109 | vm_page_flag_clear(m, PG_WINATCFLS); |
| 1110 | TAILQ_INSERT_TAIL( |
| 1111 | &vm_page_queues[PQ_INACTIVE].pl, m, pageq); |
| 1112 | m->queue = PQ_INACTIVE; |
| 1113 | vm_page_queues[PQ_INACTIVE].lcnt++; |
| 1114 | vmstats.v_inactive_count++; |
| 1115 | } |
| 1116 | } |
| 1117 | } |
| 1118 | crit_exit(); |
| 1119 | } |
| 1120 | |
| 1121 | |
| 1122 | /* |
| 1123 | * Move the specified page to the inactive queue. If the page has |
| 1124 | * any associated swap, the swap is deallocated. |
| 1125 | * |
| 1126 | * Normally athead is 0 resulting in LRU operation. athead is set |
| 1127 | * to 1 if we want this page to be 'as if it were placed in the cache', |
| 1128 | * except without unmapping it from the process address space. |
| 1129 | * |
| 1130 | * This routine may not block. |
| 1131 | */ |
| 1132 | static __inline void |
| 1133 | _vm_page_deactivate(vm_page_t m, int athead) |
| 1134 | { |
| 1135 | /* |
| 1136 | * Ignore if already inactive. |
| 1137 | */ |
| 1138 | if (m->queue == PQ_INACTIVE) |
| 1139 | return; |
| 1140 | |
| 1141 | if (m->wire_count == 0 && (m->flags & PG_UNMANAGED) == 0) { |
| 1142 | if ((m->queue - m->pc) == PQ_CACHE) |
| 1143 | mycpu->gd_cnt.v_reactivated++; |
| 1144 | vm_page_flag_clear(m, PG_WINATCFLS); |
| 1145 | vm_page_unqueue(m); |
| 1146 | if (athead) |
| 1147 | TAILQ_INSERT_HEAD(&vm_page_queues[PQ_INACTIVE].pl, m, pageq); |
| 1148 | else |
| 1149 | TAILQ_INSERT_TAIL(&vm_page_queues[PQ_INACTIVE].pl, m, pageq); |
| 1150 | m->queue = PQ_INACTIVE; |
| 1151 | vm_page_queues[PQ_INACTIVE].lcnt++; |
| 1152 | vmstats.v_inactive_count++; |
| 1153 | } |
| 1154 | } |
| 1155 | |
| 1156 | void |
| 1157 | vm_page_deactivate(vm_page_t m) |
| 1158 | { |
| 1159 | crit_enter(); |
| 1160 | _vm_page_deactivate(m, 0); |
| 1161 | crit_exit(); |
| 1162 | } |
| 1163 | |
| 1164 | /* |
| 1165 | * vm_page_try_to_cache: |
| 1166 | * |
| 1167 | * Returns 0 on failure, 1 on success |
| 1168 | */ |
| 1169 | int |
| 1170 | vm_page_try_to_cache(vm_page_t m) |
| 1171 | { |
| 1172 | crit_enter(); |
| 1173 | if (m->dirty || m->hold_count || m->busy || m->wire_count || |
| 1174 | (m->flags & (PG_BUSY|PG_UNMANAGED))) { |
| 1175 | crit_exit(); |
| 1176 | return(0); |
| 1177 | } |
| 1178 | vm_page_test_dirty(m); |
| 1179 | if (m->dirty) { |
| 1180 | crit_exit(); |
| 1181 | return(0); |
| 1182 | } |
| 1183 | vm_page_cache(m); |
| 1184 | crit_exit(); |
| 1185 | return(1); |
| 1186 | } |
| 1187 | |
| 1188 | /* |
| 1189 | * Attempt to free the page. If we cannot free it, we do nothing. |
| 1190 | * 1 is returned on success, 0 on failure. |
| 1191 | */ |
| 1192 | int |
| 1193 | vm_page_try_to_free(vm_page_t m) |
| 1194 | { |
| 1195 | crit_enter(); |
| 1196 | if (m->dirty || m->hold_count || m->busy || m->wire_count || |
| 1197 | (m->flags & (PG_BUSY|PG_UNMANAGED))) { |
| 1198 | crit_exit(); |
| 1199 | return(0); |
| 1200 | } |
| 1201 | vm_page_test_dirty(m); |
| 1202 | if (m->dirty) { |
| 1203 | crit_exit(); |
| 1204 | return(0); |
| 1205 | } |
| 1206 | vm_page_busy(m); |
| 1207 | vm_page_protect(m, VM_PROT_NONE); |
| 1208 | vm_page_free(m); |
| 1209 | crit_exit(); |
| 1210 | return(1); |
| 1211 | } |
| 1212 | |
| 1213 | /* |
| 1214 | * vm_page_cache |
| 1215 | * |
| 1216 | * Put the specified page onto the page cache queue (if appropriate). |
| 1217 | * |
| 1218 | * This routine may not block. |
| 1219 | */ |
| 1220 | void |
| 1221 | vm_page_cache(vm_page_t m) |
| 1222 | { |
| 1223 | ASSERT_IN_CRIT_SECTION(); |
| 1224 | |
| 1225 | if ((m->flags & (PG_BUSY|PG_UNMANAGED)) || m->busy || |
| 1226 | m->wire_count || m->hold_count) { |
| 1227 | kprintf("vm_page_cache: attempting to cache busy/held page\n"); |
| 1228 | return; |
| 1229 | } |
| 1230 | |
| 1231 | /* |
| 1232 | * Already in the cache (and thus not mapped) |
| 1233 | */ |
| 1234 | if ((m->queue - m->pc) == PQ_CACHE) { |
| 1235 | KKASSERT((m->flags & PG_MAPPED) == 0); |
| 1236 | return; |
| 1237 | } |
| 1238 | |
| 1239 | /* |
| 1240 | * Caller is required to test m->dirty, but note that the act of |
| 1241 | * removing the page from its maps can cause it to become dirty |
| 1242 | * on an SMP system due to another cpu running in usermode. |
| 1243 | */ |
| 1244 | if (m->dirty) { |
| 1245 | panic("vm_page_cache: caching a dirty page, pindex: %ld", |
| 1246 | (long)m->pindex); |
| 1247 | } |
| 1248 | |
| 1249 | /* |
| 1250 | * Remove all pmaps and indicate that the page is not |
| 1251 | * writeable or mapped. Our vm_page_protect() call may |
| 1252 | * have blocked (especially w/ VM_PROT_NONE), so recheck |
| 1253 | * everything. |
| 1254 | */ |
| 1255 | vm_page_busy(m); |
| 1256 | vm_page_protect(m, VM_PROT_NONE); |
| 1257 | vm_page_wakeup(m); |
| 1258 | if ((m->flags & (PG_BUSY|PG_UNMANAGED|PG_MAPPED)) || m->busy || |
| 1259 | m->wire_count || m->hold_count) { |
| 1260 | /* do nothing */ |
| 1261 | } else if (m->dirty) { |
| 1262 | vm_page_deactivate(m); |
| 1263 | } else { |
| 1264 | vm_page_unqueue_nowakeup(m); |
| 1265 | m->queue = PQ_CACHE + m->pc; |
| 1266 | vm_page_queues[m->queue].lcnt++; |
| 1267 | TAILQ_INSERT_TAIL(&vm_page_queues[m->queue].pl, m, pageq); |
| 1268 | vmstats.v_cache_count++; |
| 1269 | vm_page_free_wakeup(); |
| 1270 | } |
| 1271 | } |
| 1272 | |
| 1273 | /* |
| 1274 | * vm_page_dontneed() |
| 1275 | * |
| 1276 | * Cache, deactivate, or do nothing as appropriate. This routine |
| 1277 | * is typically used by madvise() MADV_DONTNEED. |
| 1278 | * |
| 1279 | * Generally speaking we want to move the page into the cache so |
| 1280 | * it gets reused quickly. However, this can result in a silly syndrome |
| 1281 | * due to the page recycling too quickly. Small objects will not be |
| 1282 | * fully cached. On the otherhand, if we move the page to the inactive |
| 1283 | * queue we wind up with a problem whereby very large objects |
| 1284 | * unnecessarily blow away our inactive and cache queues. |
| 1285 | * |
| 1286 | * The solution is to move the pages based on a fixed weighting. We |
| 1287 | * either leave them alone, deactivate them, or move them to the cache, |
| 1288 | * where moving them to the cache has the highest weighting. |
| 1289 | * By forcing some pages into other queues we eventually force the |
| 1290 | * system to balance the queues, potentially recovering other unrelated |
| 1291 | * space from active. The idea is to not force this to happen too |
| 1292 | * often. |
| 1293 | */ |
| 1294 | void |
| 1295 | vm_page_dontneed(vm_page_t m) |
| 1296 | { |
| 1297 | static int dnweight; |
| 1298 | int dnw; |
| 1299 | int head; |
| 1300 | |
| 1301 | dnw = ++dnweight; |
| 1302 | |
| 1303 | /* |
| 1304 | * occassionally leave the page alone |
| 1305 | */ |
| 1306 | crit_enter(); |
| 1307 | if ((dnw & 0x01F0) == 0 || |
| 1308 | m->queue == PQ_INACTIVE || |
| 1309 | m->queue - m->pc == PQ_CACHE |
| 1310 | ) { |
| 1311 | if (m->act_count >= ACT_INIT) |
| 1312 | --m->act_count; |
| 1313 | crit_exit(); |
| 1314 | return; |
| 1315 | } |
| 1316 | |
| 1317 | if (m->dirty == 0) |
| 1318 | vm_page_test_dirty(m); |
| 1319 | |
| 1320 | if (m->dirty || (dnw & 0x0070) == 0) { |
| 1321 | /* |
| 1322 | * Deactivate the page 3 times out of 32. |
| 1323 | */ |
| 1324 | head = 0; |
| 1325 | } else { |
| 1326 | /* |
| 1327 | * Cache the page 28 times out of every 32. Note that |
| 1328 | * the page is deactivated instead of cached, but placed |
| 1329 | * at the head of the queue instead of the tail. |
| 1330 | */ |
| 1331 | head = 1; |
| 1332 | } |
| 1333 | _vm_page_deactivate(m, head); |
| 1334 | crit_exit(); |
| 1335 | } |
| 1336 | |
| 1337 | /* |
| 1338 | * Grab a page, blocking if it is busy and allocating a page if necessary. |
| 1339 | * A busy page is returned or NULL. |
| 1340 | * |
| 1341 | * If VM_ALLOC_RETRY is specified VM_ALLOC_NORMAL must also be specified. |
| 1342 | * If VM_ALLOC_RETRY is not specified |
| 1343 | * |
| 1344 | * This routine may block, but if VM_ALLOC_RETRY is not set then NULL is |
| 1345 | * always returned if we had blocked. |
| 1346 | * This routine will never return NULL if VM_ALLOC_RETRY is set. |
| 1347 | * This routine may not be called from an interrupt. |
| 1348 | * The returned page may not be entirely valid. |
| 1349 | * |
| 1350 | * This routine may be called from mainline code without spl protection and |
| 1351 | * be guarenteed a busied page associated with the object at the specified |
| 1352 | * index. |
| 1353 | */ |
| 1354 | vm_page_t |
| 1355 | vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags) |
| 1356 | { |
| 1357 | vm_page_t m; |
| 1358 | int generation; |
| 1359 | |
| 1360 | KKASSERT(allocflags & |
| 1361 | (VM_ALLOC_NORMAL|VM_ALLOC_INTERRUPT|VM_ALLOC_SYSTEM)); |
| 1362 | crit_enter(); |
| 1363 | retrylookup: |
| 1364 | if ((m = vm_page_lookup(object, pindex)) != NULL) { |
| 1365 | if (m->busy || (m->flags & PG_BUSY)) { |
| 1366 | generation = object->generation; |
| 1367 | |
| 1368 | while ((object->generation == generation) && |
| 1369 | (m->busy || (m->flags & PG_BUSY))) { |
| 1370 | vm_page_flag_set(m, PG_WANTED | PG_REFERENCED); |
| 1371 | tsleep(m, 0, "pgrbwt", 0); |
| 1372 | if ((allocflags & VM_ALLOC_RETRY) == 0) { |
| 1373 | m = NULL; |
| 1374 | goto done; |
| 1375 | } |
| 1376 | } |
| 1377 | goto retrylookup; |
| 1378 | } else { |
| 1379 | vm_page_busy(m); |
| 1380 | goto done; |
| 1381 | } |
| 1382 | } |
| 1383 | m = vm_page_alloc(object, pindex, allocflags & ~VM_ALLOC_RETRY); |
| 1384 | if (m == NULL) { |
| 1385 | vm_wait(0); |
| 1386 | if ((allocflags & VM_ALLOC_RETRY) == 0) |
| 1387 | goto done; |
| 1388 | goto retrylookup; |
| 1389 | } |
| 1390 | done: |
| 1391 | crit_exit(); |
| 1392 | return(m); |
| 1393 | } |
| 1394 | |
| 1395 | /* |
| 1396 | * Mapping function for valid bits or for dirty bits in |
| 1397 | * a page. May not block. |
| 1398 | * |
| 1399 | * Inputs are required to range within a page. |
| 1400 | */ |
| 1401 | __inline int |
| 1402 | vm_page_bits(int base, int size) |
| 1403 | { |
| 1404 | int first_bit; |
| 1405 | int last_bit; |
| 1406 | |
| 1407 | KASSERT( |
| 1408 | base + size <= PAGE_SIZE, |
| 1409 | ("vm_page_bits: illegal base/size %d/%d", base, size) |
| 1410 | ); |
| 1411 | |
| 1412 | if (size == 0) /* handle degenerate case */ |
| 1413 | return(0); |
| 1414 | |
| 1415 | first_bit = base >> DEV_BSHIFT; |
| 1416 | last_bit = (base + size - 1) >> DEV_BSHIFT; |
| 1417 | |
| 1418 | return ((2 << last_bit) - (1 << first_bit)); |
| 1419 | } |
| 1420 | |
| 1421 | /* |
| 1422 | * Sets portions of a page valid and clean. The arguments are expected |
| 1423 | * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive |
| 1424 | * of any partial chunks touched by the range. The invalid portion of |
| 1425 | * such chunks will be zero'd. |
| 1426 | * |
| 1427 | * This routine may not block. |
| 1428 | * |
| 1429 | * (base + size) must be less then or equal to PAGE_SIZE. |
| 1430 | */ |
| 1431 | void |
| 1432 | vm_page_set_validclean(vm_page_t m, int base, int size) |
| 1433 | { |
| 1434 | int pagebits; |
| 1435 | int frag; |
| 1436 | int endoff; |
| 1437 | |
| 1438 | if (size == 0) /* handle degenerate case */ |
| 1439 | return; |
| 1440 | |
| 1441 | /* |
| 1442 | * If the base is not DEV_BSIZE aligned and the valid |
| 1443 | * bit is clear, we have to zero out a portion of the |
| 1444 | * first block. |
| 1445 | */ |
| 1446 | |
| 1447 | if ((frag = base & ~(DEV_BSIZE - 1)) != base && |
| 1448 | (m->valid & (1 << (base >> DEV_BSHIFT))) == 0 |
| 1449 | ) { |
| 1450 | pmap_zero_page_area( |
| 1451 | VM_PAGE_TO_PHYS(m), |
| 1452 | frag, |
| 1453 | base - frag |
| 1454 | ); |
| 1455 | } |
| 1456 | |
| 1457 | /* |
| 1458 | * If the ending offset is not DEV_BSIZE aligned and the |
| 1459 | * valid bit is clear, we have to zero out a portion of |
| 1460 | * the last block. |
| 1461 | */ |
| 1462 | |
| 1463 | endoff = base + size; |
| 1464 | |
| 1465 | if ((frag = endoff & ~(DEV_BSIZE - 1)) != endoff && |
| 1466 | (m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0 |
| 1467 | ) { |
| 1468 | pmap_zero_page_area( |
| 1469 | VM_PAGE_TO_PHYS(m), |
| 1470 | endoff, |
| 1471 | DEV_BSIZE - (endoff & (DEV_BSIZE - 1)) |
| 1472 | ); |
| 1473 | } |
| 1474 | |
| 1475 | /* |
| 1476 | * Set valid, clear dirty bits. If validating the entire |
| 1477 | * page we can safely clear the pmap modify bit. We also |
| 1478 | * use this opportunity to clear the PG_NOSYNC flag. If a process |
| 1479 | * takes a write fault on a MAP_NOSYNC memory area the flag will |
| 1480 | * be set again. |
| 1481 | * |
| 1482 | * We set valid bits inclusive of any overlap, but we can only |
| 1483 | * clear dirty bits for DEV_BSIZE chunks that are fully within |
| 1484 | * the range. |
| 1485 | */ |
| 1486 | |
| 1487 | pagebits = vm_page_bits(base, size); |
| 1488 | m->valid |= pagebits; |
| 1489 | #if 0 /* NOT YET */ |
| 1490 | if ((frag = base & (DEV_BSIZE - 1)) != 0) { |
| 1491 | frag = DEV_BSIZE - frag; |
| 1492 | base += frag; |
| 1493 | size -= frag; |
| 1494 | if (size < 0) |
| 1495 | size = 0; |
| 1496 | } |
| 1497 | pagebits = vm_page_bits(base, size & (DEV_BSIZE - 1)); |
| 1498 | #endif |
| 1499 | m->dirty &= ~pagebits; |
| 1500 | if (base == 0 && size == PAGE_SIZE) { |
| 1501 | pmap_clear_modify(m); |
| 1502 | vm_page_flag_clear(m, PG_NOSYNC); |
| 1503 | } |
| 1504 | } |
| 1505 | |
| 1506 | void |
| 1507 | vm_page_clear_dirty(vm_page_t m, int base, int size) |
| 1508 | { |
| 1509 | m->dirty &= ~vm_page_bits(base, size); |
| 1510 | } |
| 1511 | |
| 1512 | /* |
| 1513 | * Make the page all-dirty. |
| 1514 | * |
| 1515 | * Also make sure the related object and vnode reflect the fact that the |
| 1516 | * object may now contain a dirty page. |
| 1517 | */ |
| 1518 | void |
| 1519 | vm_page_dirty(vm_page_t m) |
| 1520 | { |
| 1521 | #ifdef INVARIANTS |
| 1522 | int pqtype = m->queue - m->pc; |
| 1523 | #endif |
| 1524 | KASSERT(pqtype != PQ_CACHE && pqtype != PQ_FREE, |
| 1525 | ("vm_page_dirty: page in free/cache queue!")); |
| 1526 | if (m->dirty != VM_PAGE_BITS_ALL) { |
| 1527 | m->dirty = VM_PAGE_BITS_ALL; |
| 1528 | if (m->object) |
| 1529 | vm_object_set_writeable_dirty(m->object); |
| 1530 | } |
| 1531 | } |
| 1532 | |
| 1533 | /* |
| 1534 | * Invalidates DEV_BSIZE'd chunks within a page. Both the |
| 1535 | * valid and dirty bits for the effected areas are cleared. |
| 1536 | * |
| 1537 | * May not block. |
| 1538 | */ |
| 1539 | void |
| 1540 | vm_page_set_invalid(vm_page_t m, int base, int size) |
| 1541 | { |
| 1542 | int bits; |
| 1543 | |
| 1544 | bits = vm_page_bits(base, size); |
| 1545 | m->valid &= ~bits; |
| 1546 | m->dirty &= ~bits; |
| 1547 | m->object->generation++; |
| 1548 | } |
| 1549 | |
| 1550 | /* |
| 1551 | * The kernel assumes that the invalid portions of a page contain |
| 1552 | * garbage, but such pages can be mapped into memory by user code. |
| 1553 | * When this occurs, we must zero out the non-valid portions of the |
| 1554 | * page so user code sees what it expects. |
| 1555 | * |
| 1556 | * Pages are most often semi-valid when the end of a file is mapped |
| 1557 | * into memory and the file's size is not page aligned. |
| 1558 | */ |
| 1559 | void |
| 1560 | vm_page_zero_invalid(vm_page_t m, boolean_t setvalid) |
| 1561 | { |
| 1562 | int b; |
| 1563 | int i; |
| 1564 | |
| 1565 | /* |
| 1566 | * Scan the valid bits looking for invalid sections that |
| 1567 | * must be zerod. Invalid sub-DEV_BSIZE'd areas ( where the |
| 1568 | * valid bit may be set ) have already been zerod by |
| 1569 | * vm_page_set_validclean(). |
| 1570 | */ |
| 1571 | for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) { |
| 1572 | if (i == (PAGE_SIZE / DEV_BSIZE) || |
| 1573 | (m->valid & (1 << i)) |
| 1574 | ) { |
| 1575 | if (i > b) { |
| 1576 | pmap_zero_page_area( |
| 1577 | VM_PAGE_TO_PHYS(m), |
| 1578 | b << DEV_BSHIFT, |
| 1579 | (i - b) << DEV_BSHIFT |
| 1580 | ); |
| 1581 | } |
| 1582 | b = i + 1; |
| 1583 | } |
| 1584 | } |
| 1585 | |
| 1586 | /* |
| 1587 | * setvalid is TRUE when we can safely set the zero'd areas |
| 1588 | * as being valid. We can do this if there are no cache consistency |
| 1589 | * issues. e.g. it is ok to do with UFS, but not ok to do with NFS. |
| 1590 | */ |
| 1591 | if (setvalid) |
| 1592 | m->valid = VM_PAGE_BITS_ALL; |
| 1593 | } |
| 1594 | |
| 1595 | /* |
| 1596 | * Is a (partial) page valid? Note that the case where size == 0 |
| 1597 | * will return FALSE in the degenerate case where the page is entirely |
| 1598 | * invalid, and TRUE otherwise. |
| 1599 | * |
| 1600 | * May not block. |
| 1601 | */ |
| 1602 | int |
| 1603 | vm_page_is_valid(vm_page_t m, int base, int size) |
| 1604 | { |
| 1605 | int bits = vm_page_bits(base, size); |
| 1606 | |
| 1607 | if (m->valid && ((m->valid & bits) == bits)) |
| 1608 | return 1; |
| 1609 | else |
| 1610 | return 0; |
| 1611 | } |
| 1612 | |
| 1613 | /* |
| 1614 | * update dirty bits from pmap/mmu. May not block. |
| 1615 | */ |
| 1616 | void |
| 1617 | vm_page_test_dirty(vm_page_t m) |
| 1618 | { |
| 1619 | if ((m->dirty != VM_PAGE_BITS_ALL) && pmap_is_modified(m)) { |
| 1620 | vm_page_dirty(m); |
| 1621 | } |
| 1622 | } |
| 1623 | |
| 1624 | /* |
| 1625 | * Issue an event on a VM page. Corresponding action structures are |
| 1626 | * removed from the page's list and called. |
| 1627 | */ |
| 1628 | void |
| 1629 | vm_page_event_internal(vm_page_t m, vm_page_event_t event) |
| 1630 | { |
| 1631 | struct vm_page_action *scan, *next; |
| 1632 | |
| 1633 | LIST_FOREACH_MUTABLE(scan, &m->action_list, entry, next) { |
| 1634 | if (scan->event == event) { |
| 1635 | scan->event = VMEVENT_NONE; |
| 1636 | LIST_REMOVE(scan, entry); |
| 1637 | scan->func(m, scan); |
| 1638 | } |
| 1639 | } |
| 1640 | } |
| 1641 | |
| 1642 | #include "opt_ddb.h" |
| 1643 | #ifdef DDB |
| 1644 | #include <sys/kernel.h> |
| 1645 | |
| 1646 | #include <ddb/ddb.h> |
| 1647 | |
| 1648 | DB_SHOW_COMMAND(page, vm_page_print_page_info) |
| 1649 | { |
| 1650 | db_printf("vmstats.v_free_count: %d\n", vmstats.v_free_count); |
| 1651 | db_printf("vmstats.v_cache_count: %d\n", vmstats.v_cache_count); |
| 1652 | db_printf("vmstats.v_inactive_count: %d\n", vmstats.v_inactive_count); |
| 1653 | db_printf("vmstats.v_active_count: %d\n", vmstats.v_active_count); |
| 1654 | db_printf("vmstats.v_wire_count: %d\n", vmstats.v_wire_count); |
| 1655 | db_printf("vmstats.v_free_reserved: %d\n", vmstats.v_free_reserved); |
| 1656 | db_printf("vmstats.v_free_min: %d\n", vmstats.v_free_min); |
| 1657 | db_printf("vmstats.v_free_target: %d\n", vmstats.v_free_target); |
| 1658 | db_printf("vmstats.v_cache_min: %d\n", vmstats.v_cache_min); |
| 1659 | db_printf("vmstats.v_inactive_target: %d\n", vmstats.v_inactive_target); |
| 1660 | } |
| 1661 | |
| 1662 | DB_SHOW_COMMAND(pageq, vm_page_print_pageq_info) |
| 1663 | { |
| 1664 | int i; |
| 1665 | db_printf("PQ_FREE:"); |
| 1666 | for(i=0;i<PQ_L2_SIZE;i++) { |
| 1667 | db_printf(" %d", vm_page_queues[PQ_FREE + i].lcnt); |
| 1668 | } |
| 1669 | db_printf("\n"); |
| 1670 | |
| 1671 | db_printf("PQ_CACHE:"); |
| 1672 | for(i=0;i<PQ_L2_SIZE;i++) { |
| 1673 | db_printf(" %d", vm_page_queues[PQ_CACHE + i].lcnt); |
| 1674 | } |
| 1675 | db_printf("\n"); |
| 1676 | |
| 1677 | db_printf("PQ_ACTIVE: %d, PQ_INACTIVE: %d\n", |
| 1678 | vm_page_queues[PQ_ACTIVE].lcnt, |
| 1679 | vm_page_queues[PQ_INACTIVE].lcnt); |
| 1680 | } |
| 1681 | #endif /* DDB */ |