vm_page.c revision 101250
1210008Srdivacky/* 2210008Srdivacky * Copyright (c) 1991 Regents of the University of California. 3210008Srdivacky * All rights reserved. 4210008Srdivacky * 5210008Srdivacky * This code is derived from software contributed to Berkeley by 6210008Srdivacky * The Mach Operating System project at Carnegie-Mellon University. 7210008Srdivacky * 8210008Srdivacky * Redistribution and use in source and binary forms, with or without 9210008Srdivacky * modification, are permitted provided that the following conditions 10210008Srdivacky * are met: 11210008Srdivacky * 1. Redistributions of source code must retain the above copyright 12210008Srdivacky * notice, this list of conditions and the following disclaimer. 13210008Srdivacky * 2. Redistributions in binary form must reproduce the above copyright 14210008Srdivacky * notice, this list of conditions and the following disclaimer in the 15210008Srdivacky * documentation and/or other materials provided with the distribution. 16249423Sdim * 3. All advertising materials mentioning features or use of this software 17210008Srdivacky * must display the following acknowledgement: 18210008Srdivacky * This product includes software developed by the University of 19249423Sdim * California, Berkeley and its contributors. 20249423Sdim * 4. Neither the name of the University nor the names of its contributors 21249423Sdim * may be used to endorse or promote products derived from this software 22210008Srdivacky * without specific prior written permission. 23210008Srdivacky * 24210008Srdivacky * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25210008Srdivacky * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26210008Srdivacky * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27210008Srdivacky * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28210008Srdivacky * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29210008Srdivacky * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30210008Srdivacky * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31210008Srdivacky * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32218893Sdim * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33218893Sdim * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34210008Srdivacky * SUCH DAMAGE. 35210008Srdivacky * 36210008Srdivacky * from: @(#)vm_page.c 7.4 (Berkeley) 5/7/91 37210008Srdivacky * $FreeBSD: head/sys/vm/vm_page.c 101250 2002-08-03 01:29:52Z alc $ 38210008Srdivacky */ 39210008Srdivacky 40210008Srdivacky/* 41210008Srdivacky * Copyright (c) 1987, 1990 Carnegie-Mellon University. 42210008Srdivacky * All rights reserved. 43234353Sdim * 44210008Srdivacky * Authors: Avadis Tevanian, Jr., Michael Wayne Young 45210008Srdivacky * 46210008Srdivacky * Permission to use, copy, modify and distribute this software and 47210008Srdivacky * its documentation is hereby granted, provided that both the copyright 48221345Sdim * notice and this permission notice appear in all copies of the 49221345Sdim * software, derivative works or modified versions, and any portions 50221345Sdim * thereof, and that both notices appear in supporting documentation. 51221345Sdim * 52210008Srdivacky * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 53210008Srdivacky * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 54218893Sdim * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 55218893Sdim * 56218893Sdim * Carnegie Mellon requests users of this software to return to 57218893Sdim * 58218893Sdim * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 59218893Sdim * School of Computer Science 60221345Sdim * Carnegie Mellon University 61218893Sdim * Pittsburgh PA 15213-3890 62218893Sdim * 63218893Sdim * any improvements or extensions that they make and grant Carnegie the 64218893Sdim * rights to redistribute these changes. 65239462Sdim */ 66221345Sdim 67218893Sdim/* 68218893Sdim * GENERAL RULES ON VM_PAGE MANIPULATION 69218893Sdim * 70210008Srdivacky * - a pageq mutex is required when adding or removing a page from a 71210008Srdivacky * page queue (vm_page_queue[]), regardless of other mutexes or the 72210008Srdivacky * busy state of a page. 73210008Srdivacky * 74210008Srdivacky * - a hash chain mutex is required when associating or disassociating 75210008Srdivacky * a page from the VM PAGE CACHE hash table (vm_page_buckets), 76239462Sdim * regardless of other mutexes or the busy state of a page. 77239462Sdim * 78239462Sdim * - either a hash chain mutex OR a busied page is required in order 79239462Sdim * to modify the page flags. A hash chain mutex must be obtained in 80239462Sdim * order to busy a page. A page's flags cannot be modified by a 81239462Sdim * hash chain mutex if the page is marked busy. 82239462Sdim * 83239462Sdim * - The object memq mutex is held when inserting or removing 84239462Sdim * pages from an object (vm_page_insert() or vm_page_remove()). This 85239462Sdim * is different from the object's main mutex. 86239462Sdim * 87239462Sdim * Generally speaking, you have to be aware of side effects when running 88249423Sdim * vm_page ops. A vm_page_lookup() will return with the hash chain 89249423Sdim * locked, whether it was able to lookup the page or not. vm_page_free(), 90249423Sdim * vm_page_cache(), vm_page_activate(), and a number of other routines 91249423Sdim * will release the hash chain mutex for you. Intermediate manipulation 92249423Sdim * routines such as vm_page_flag_set() expect the hash chain to be held 93249423Sdim * on entry and the hash chain will remain held on return. 94249423Sdim * 95249423Sdim * pageq scanning can only occur with the pageq in question locked. 96249423Sdim * We have a known bottleneck with the active queue, but the cache 97249423Sdim * and free queues are actually arrays already. 98249423Sdim */ 99249423Sdim 100249423Sdim/* 101249423Sdim * Resident memory management module. 102210008Srdivacky */ 103210008Srdivacky 104234353Sdim#include <sys/param.h> 105210008Srdivacky#include <sys/systm.h> 106210008Srdivacky#include <sys/lock.h> 107218893Sdim#include <sys/malloc.h> 108218893Sdim#include <sys/mutex.h> 109218893Sdim#include <sys/proc.h> 110218893Sdim#include <sys/vmmeter.h> 111218893Sdim#include <sys/vnode.h> 112218893Sdim 113234353Sdim#include <vm/vm.h> 114234353Sdim#include <vm/vm_param.h> 115210008Srdivacky#include <vm/vm_kern.h> 116210008Srdivacky#include <vm/vm_object.h> 117210008Srdivacky#include <vm/vm_page.h> 118210008Srdivacky#include <vm/vm_pageout.h> 119210008Srdivacky#include <vm/vm_pager.h> 120210008Srdivacky#include <vm/vm_extern.h> 121210008Srdivacky#include <vm/uma.h> 122210008Srdivacky#include <vm/uma_int.h> 123234353Sdim 124210008Srdivacky/* 125210008Srdivacky * Associated with page of user-allocatable memory is a 126210008Srdivacky * page structure. 127210008Srdivacky */ 128210008Srdivackystatic struct mtx vm_page_buckets_mtx; 129210008Srdivackystatic struct vm_page **vm_page_buckets; /* Array of buckets */ 130210008Srdivackystatic int vm_page_bucket_count; /* How big is array? */ 131218893Sdimstatic int vm_page_hash_mask; /* Mask for hash function */ 132218893Sdim 133210008Srdivackystruct mtx vm_page_queue_mtx; 134210008Srdivackystruct mtx vm_page_queue_free_mtx; 135210008Srdivacky 136243830Sdimvm_page_t vm_page_array = 0; 137251662Sdimint vm_page_array_size = 0; 138218893Sdimlong first_page = 0; 139234353Sdimint vm_page_zero_count = 0; 140210008Srdivacky 141239462Sdim/* 142210008Srdivacky * vm_set_page_size: 143239462Sdim * 144239462Sdim * Sets the page size, perhaps based upon the memory 145210008Srdivacky * size. Must be called before any use of page-size 146218893Sdim * dependent functions. 147218893Sdim */ 148218893Sdimvoid 149221345Sdimvm_set_page_size(void) 150218893Sdim{ 151218893Sdim if (cnt.v_page_size == 0) 152218893Sdim cnt.v_page_size = PAGE_SIZE; 153218893Sdim if (((cnt.v_page_size - 1) & cnt.v_page_size) != 0) 154218893Sdim panic("vm_set_page_size: page size not a power of two"); 155218893Sdim} 156218893Sdim 157218893Sdim/* 158263508Sdim * vm_page_startup: 159218893Sdim * 160218893Sdim * Initializes the resident memory module. 161218893Sdim * 162218893Sdim * Allocates memory for the page cells, and 163218893Sdim * for the object/offset-to-page hash table headers. 164218893Sdim * Each page cell is initialized and placed on the free list. 165218893Sdim */ 166218893Sdimvm_offset_t 167218893Sdimvm_page_startup(vm_offset_t starta, vm_offset_t enda, vm_offset_t vaddr) 168218893Sdim{ 169218893Sdim vm_offset_t mapped; 170234353Sdim struct vm_page **bucket; 171221345Sdim vm_size_t npages, page_range; 172221345Sdim vm_offset_t new_end; 173218893Sdim int i; 174218893Sdim vm_offset_t pa; 175218893Sdim int nblocks; 176239462Sdim vm_offset_t last_pa; 177234353Sdim 178234353Sdim /* the biggest memory array is the second group of pages */ 179234353Sdim vm_offset_t end; 180218893Sdim vm_offset_t biggestone, biggestsize; 181218893Sdim 182218893Sdim vm_offset_t total; 183223017Sdim vm_size_t bootpages; 184224145Sdim 185226633Sdim total = 0; 186218893Sdim biggestsize = 0; 187218893Sdim biggestone = 0; 188210008Srdivacky nblocks = 0; 189224145Sdim vaddr = round_page(vaddr); 190224145Sdim 191224145Sdim for (i = 0; phys_avail[i + 1]; i += 2) { 192210008Srdivacky phys_avail[i] = round_page(phys_avail[i]); 193210008Srdivacky phys_avail[i + 1] = trunc_page(phys_avail[i + 1]); 194210008Srdivacky } 195210008Srdivacky 196210008Srdivacky for (i = 0; phys_avail[i + 1]; i += 2) { 197210008Srdivacky vm_size_t size = phys_avail[i + 1] - phys_avail[i]; 198210008Srdivacky 199210008Srdivacky if (size > biggestsize) { 200210008Srdivacky biggestone = i; 201210008Srdivacky biggestsize = size; 202210008Srdivacky } 203221345Sdim ++nblocks; 204221345Sdim total += size; 205221345Sdim } 206210008Srdivacky 207210008Srdivacky end = phys_avail[biggestone+1]; 208210008Srdivacky 209210008Srdivacky /* 210210008Srdivacky * Initialize the locks. 211210008Srdivacky */ 212210008Srdivacky mtx_init(&vm_page_queue_mtx, "vm page queue mutex", NULL, MTX_DEF); 213210008Srdivacky mtx_init(&vm_page_queue_free_mtx, "vm page queue free mutex", NULL, 214210008Srdivacky MTX_SPIN); 215210008Srdivacky 216210008Srdivacky /* 217212904Sdim * Initialize the queue headers for the free queue, the active queue 218210008Srdivacky * and the inactive queue. 219210008Srdivacky */ 220210008Srdivacky vm_pageq_init(); 221212904Sdim 222210008Srdivacky /* 223210008Srdivacky * Allocate memory for use when boot strapping the kernel memory allocator 224218893Sdim */ 225218893Sdim bootpages = UMA_BOOT_PAGES * UMA_SLAB_SIZE; 226218893Sdim new_end = end - bootpages; 227218893Sdim new_end = trunc_page(new_end); 228218893Sdim mapped = pmap_map(&vaddr, new_end, end, 229218893Sdim VM_PROT_READ | VM_PROT_WRITE); 230218893Sdim bzero((caddr_t) mapped, end - new_end); 231218893Sdim uma_startup((caddr_t)mapped); 232218893Sdim 233218893Sdim end = new_end; 234218893Sdim 235218893Sdim /* 236218893Sdim * Allocate (and initialize) the hash table buckets. 237210008Srdivacky * 238210008Srdivacky * The number of buckets MUST BE a power of 2, and the actual value is 239210008Srdivacky * the next power of 2 greater than the number of physical pages in 240212904Sdim * the system. 241212904Sdim * 242210008Srdivacky * We make the hash table approximately 2x the number of pages to 243210008Srdivacky * reduce the chain length. This is about the same size using the 244210008Srdivacky * singly-linked list as the 1x hash table we were using before 245210008Srdivacky * using TAILQ but the chain length will be smaller. 246210008Srdivacky * 247210008Srdivacky * Note: This computation can be tweaked if desired. 248218893Sdim */ 249234353Sdim if (vm_page_bucket_count == 0) { 250234353Sdim vm_page_bucket_count = 1; 251234353Sdim while (vm_page_bucket_count < atop(total)) 252234353Sdim vm_page_bucket_count <<= 1; 253218893Sdim } 254234353Sdim vm_page_bucket_count <<= 1; 255218893Sdim vm_page_hash_mask = vm_page_bucket_count - 1; 256210008Srdivacky 257210008Srdivacky /* 258210008Srdivacky * Validate these addresses. 259234353Sdim */ 260210008Srdivacky new_end = end - vm_page_bucket_count * sizeof(struct vm_page *); 261210008Srdivacky new_end = trunc_page(new_end); 262210008Srdivacky mapped = pmap_map(&vaddr, new_end, end, 263210008Srdivacky VM_PROT_READ | VM_PROT_WRITE); 264210008Srdivacky bzero((caddr_t) mapped, end - new_end); 265210008Srdivacky 266234353Sdim mtx_init(&vm_page_buckets_mtx, "vm page buckets mutex", NULL, MTX_SPIN); 267221345Sdim vm_page_buckets = (struct vm_page **)mapped; 268221345Sdim bucket = vm_page_buckets; 269221345Sdim for (i = 0; i < vm_page_bucket_count; i++) { 270221345Sdim *bucket = NULL; 271221345Sdim bucket++; 272221345Sdim } 273221345Sdim 274210008Srdivacky /* 275210008Srdivacky * Compute the number of pages of memory that will be available for 276210008Srdivacky * use (taking into account the overhead of a page structure per 277210008Srdivacky * page). 278210008Srdivacky */ 279210008Srdivacky first_page = phys_avail[0] / PAGE_SIZE; 280210008Srdivacky page_range = phys_avail[(nblocks - 1) * 2 + 1] / PAGE_SIZE - first_page; 281210008Srdivacky npages = (total - (page_range * sizeof(struct vm_page)) - 282210008Srdivacky (end - new_end)) / PAGE_SIZE; 283210008Srdivacky end = new_end; 284234353Sdim 285218893Sdim /* 286210008Srdivacky * Initialize the mem entry structures now, and put them in the free 287210008Srdivacky * queue. 288210008Srdivacky */ 289210008Srdivacky new_end = trunc_page(end - page_range * sizeof(struct vm_page)); 290263508Sdim mapped = pmap_map(&vaddr, new_end, end, 291210008Srdivacky VM_PROT_READ | VM_PROT_WRITE); 292210008Srdivacky vm_page_array = (vm_page_t) mapped; 293210008Srdivacky 294210008Srdivacky /* 295263508Sdim * Clear all of the page structures 296263508Sdim */ 297263508Sdim bzero((caddr_t) vm_page_array, page_range * sizeof(struct vm_page)); 298263508Sdim vm_page_array_size = page_range; 299263508Sdim 300210008Srdivacky /* 301210008Srdivacky * Construct the free queue(s) in descending order (by physical 302210008Srdivacky * address) so that the first 16MB of physical memory is allocated 303210008Srdivacky * last rather than first. On large-memory machines, this avoids 304210008Srdivacky * the exhaustion of low physical memory before isa_dmainit has run. 305251662Sdim */ 306251662Sdim cnt.v_page_count = 0; 307251662Sdim cnt.v_free_count = 0; 308251662Sdim for (i = 0; phys_avail[i + 1] && npages > 0; i += 2) { 309210008Srdivacky pa = phys_avail[i]; 310210008Srdivacky if (i == biggestone) 311210008Srdivacky last_pa = new_end; 312210008Srdivacky else 313218893Sdim last_pa = phys_avail[i + 1]; 314218893Sdim while (pa < last_pa && npages-- > 0) { 315218893Sdim vm_pageq_add_new_page(pa); 316210008Srdivacky pa += PAGE_SIZE; 317210008Srdivacky } 318210008Srdivacky } 319210008Srdivacky return (vaddr); 320210008Srdivacky} 321210008Srdivacky 322210008Srdivacky/* 323210008Srdivacky * vm_page_hash: 324224145Sdim * 325210008Srdivacky * Distributes the object/offset key pair among hash buckets. 326210008Srdivacky * 327210008Srdivacky * NOTE: This macro depends on vm_page_bucket_count being a power of 2. 328210008Srdivacky * This routine may not block. 329224145Sdim * 330224145Sdim * We try to randomize the hash based on the object to spread the pages 331224145Sdim * out in the hash table without it costing us too much. 332224145Sdim */ 333218893Sdimstatic __inline int 334218893Sdimvm_page_hash(vm_object_t object, vm_pindex_t pindex) 335218893Sdim{ 336218893Sdim int i = ((uintptr_t)object + pindex) ^ object->hash_rand; 337218893Sdim 338218893Sdim return (i & vm_page_hash_mask); 339218893Sdim} 340210008Srdivacky 341210008Srdivackyvoid 342218893Sdimvm_page_flag_set(vm_page_t m, unsigned short bits) 343218893Sdim{ 344218893Sdim GIANT_REQUIRED; 345210008Srdivacky m->flags |= bits; 346210008Srdivacky} 347210008Srdivacky 348210008Srdivackyvoid 349210008Srdivackyvm_page_flag_clear(vm_page_t m, unsigned short bits) 350210008Srdivacky{ 351221345Sdim GIANT_REQUIRED; 352221345Sdim m->flags &= ~bits; 353210008Srdivacky} 354218893Sdim 355218893Sdimvoid 356210008Srdivackyvm_page_busy(vm_page_t m) 357210008Srdivacky{ 358210008Srdivacky KASSERT((m->flags & PG_BUSY) == 0, 359234353Sdim ("vm_page_busy: page already busy!!!")); 360263508Sdim vm_page_flag_set(m, PG_BUSY); 361210008Srdivacky} 362210008Srdivacky 363218893Sdim/* 364218893Sdim * vm_page_flash: 365234353Sdim * 366218893Sdim * wakeup anyone waiting for the page. 367218893Sdim */ 368234353Sdimvoid 369218893Sdimvm_page_flash(vm_page_t m) 370218893Sdim{ 371218893Sdim if (m->flags & PG_WANTED) { 372218893Sdim vm_page_flag_clear(m, PG_WANTED); 373210008Srdivacky wakeup(m); 374210008Srdivacky } 375234353Sdim} 376218893Sdim 377218893Sdim/* 378234353Sdim * vm_page_wakeup: 379218893Sdim * 380218893Sdim * clear the PG_BUSY flag and wakeup anyone waiting for the 381234353Sdim * page. 382224145Sdim * 383224145Sdim */ 384224145Sdimvoid 385224145Sdimvm_page_wakeup(vm_page_t m) 386234353Sdim{ 387234353Sdim KASSERT(m->flags & PG_BUSY, ("vm_page_wakeup: page not busy!!!")); 388234353Sdim vm_page_flag_clear(m, PG_BUSY); 389234353Sdim vm_page_flash(m); 390234353Sdim} 391234353Sdim 392234353Sdim/* 393234353Sdim * 394234353Sdim * 395234353Sdim */ 396234353Sdimvoid 397218893Sdimvm_page_io_start(vm_page_t m) 398234353Sdim{ 399218893Sdim 400210008Srdivacky mtx_assert(&vm_page_queue_mtx, MA_OWNED); 401210008Srdivacky m->busy++; 402210008Srdivacky} 403210008Srdivacky 404210008Srdivackyvoid 405210008Srdivackyvm_page_io_finish(vm_page_t m) 406210008Srdivacky{ 407210008Srdivacky 408210008Srdivacky mtx_assert(&vm_page_queue_mtx, MA_OWNED); 409210008Srdivacky m->busy--; 410210008Srdivacky if (m->busy == 0) 411212904Sdim vm_page_flash(m); 412212904Sdim} 413212904Sdim 414212904Sdim/* 415210008Srdivacky * Keep page from being freed by the page daemon 416210008Srdivacky * much of the same effect as wiring, except much lower 417210008Srdivacky * overhead and should be used only for *very* temporary 418210008Srdivacky * holding ("wiring"). 419210008Srdivacky */ 420210008Srdivackyvoid 421218893Sdimvm_page_hold(vm_page_t mem) 422234353Sdim{ 423210008Srdivacky GIANT_REQUIRED; 424210008Srdivacky mem->hold_count++; 425210008Srdivacky} 426210008Srdivacky 427210008Srdivackyvoid 428210008Srdivackyvm_page_unhold(vm_page_t mem) 429210008Srdivacky{ 430210008Srdivacky GIANT_REQUIRED; 431210008Srdivacky --mem->hold_count; 432210008Srdivacky KASSERT(mem->hold_count >= 0, ("vm_page_unhold: hold count < 0!!!")); 433234353Sdim if (mem->hold_count == 0 && mem->queue == PQ_HOLD) 434210008Srdivacky vm_page_free_toq(mem); 435210008Srdivacky} 436210008Srdivacky 437226633Sdim/* 438210008Srdivacky * vm_page_protect: 439210008Srdivacky * 440210008Srdivacky * Reduce the protection of a page. This routine never raises the 441210008Srdivacky * protection and therefore can be safely called if the page is already 442210008Srdivacky * at VM_PROT_NONE (it will be a NOP effectively ). 443239462Sdim */ 444210008Srdivackyvoid 445210008Srdivackyvm_page_protect(vm_page_t mem, int prot) 446210008Srdivacky{ 447210008Srdivacky if (prot == VM_PROT_NONE) { 448210008Srdivacky if (mem->flags & (PG_WRITEABLE|PG_MAPPED)) { 449221345Sdim pmap_page_protect(mem, VM_PROT_NONE); 450221345Sdim vm_page_flag_clear(mem, PG_WRITEABLE|PG_MAPPED); 451221345Sdim } 452221345Sdim } else if ((prot == VM_PROT_READ) && (mem->flags & PG_WRITEABLE)) { 453210008Srdivacky pmap_page_protect(mem, VM_PROT_READ); 454234353Sdim vm_page_flag_clear(mem, PG_WRITEABLE); 455210008Srdivacky } 456210008Srdivacky} 457210008Srdivacky/* 458210008Srdivacky * vm_page_zero_fill: 459210008Srdivacky * 460210008Srdivacky * Zero-fill the specified page. 461218893Sdim * Written as a standard pagein routine, to 462218893Sdim * be used by the zero-fill object. 463210008Srdivacky */ 464210008Srdivackyboolean_t 465210008Srdivackyvm_page_zero_fill(vm_page_t m) 466210008Srdivacky{ 467210008Srdivacky pmap_zero_page(m); 468210008Srdivacky return (TRUE); 469210008Srdivacky} 470210008Srdivacky 471210008Srdivacky/* 472210008Srdivacky * vm_page_zero_fill_area: 473210008Srdivacky * 474210008Srdivacky * Like vm_page_zero_fill but only fill the specified area. 475210008Srdivacky */ 476210008Srdivackyboolean_t 477210008Srdivackyvm_page_zero_fill_area(vm_page_t m, int off, int size) 478210008Srdivacky{ 479210008Srdivacky pmap_zero_page_area(m, off, size); 480210008Srdivacky return (TRUE); 481210008Srdivacky} 482210008Srdivacky 483210008Srdivacky/* 484210008Srdivacky * vm_page_copy: 485210008Srdivacky * 486210008Srdivacky * Copy one page to another 487218893Sdim */ 488218893Sdimvoid 489218893Sdimvm_page_copy(vm_page_t src_m, vm_page_t dest_m) 490210008Srdivacky{ 491210008Srdivacky pmap_copy_page(src_m, dest_m); 492210008Srdivacky dest_m->valid = VM_PAGE_BITS_ALL; 493210008Srdivacky} 494210008Srdivacky 495210008Srdivacky/* 496210008Srdivacky * vm_page_free: 497210008Srdivacky * 498210008Srdivacky * Free a page 499210008Srdivacky * 500210008Srdivacky * The clearing of PG_ZERO is a temporary safety until the code can be 501210008Srdivacky * reviewed to determine that PG_ZERO is being properly cleared on 502210008Srdivacky * write faults or maps. PG_ZERO was previously cleared in 503210008Srdivacky * vm_page_alloc(). 504210008Srdivacky */ 505210008Srdivackyvoid 506234353Sdimvm_page_free(vm_page_t m) 507210008Srdivacky{ 508210008Srdivacky vm_page_flag_clear(m, PG_ZERO); 509218893Sdim vm_page_free_toq(m); 510210008Srdivacky vm_page_zero_idle_wakeup(); 511218893Sdim} 512218893Sdim 513210008Srdivacky/* 514210008Srdivacky * vm_page_free_zero: 515210008Srdivacky * 516212904Sdim * Free a page to the zerod-pages queue 517210008Srdivacky */ 518210008Srdivackyvoid 519210008Srdivackyvm_page_free_zero(vm_page_t m) 520210008Srdivacky{ 521210008Srdivacky vm_page_flag_set(m, PG_ZERO); 522212904Sdim vm_page_free_toq(m); 523234353Sdim} 524234353Sdim 525223017Sdim/* 526223017Sdim * vm_page_sleep_busy: 527210008Srdivacky * 528210008Srdivacky * Wait until page is no longer PG_BUSY or (if also_m_busy is TRUE) 529210008Srdivacky * m->busy is zero. Returns TRUE if it had to sleep ( including if 530212904Sdim * it almost had to sleep and made temporary spl*() mods), FALSE 531234353Sdim * otherwise. 532234353Sdim * 533223017Sdim * This routine assumes that interrupts can only remove the busy 534223017Sdim * status from a page, not set the busy status or change it from 535210008Srdivacky * PG_BUSY to m->busy or vise versa (which would create a timing 536210008Srdivacky * window). 537210008Srdivacky */ 538210008Srdivackyint 539210008Srdivackyvm_page_sleep_busy(vm_page_t m, int also_m_busy, const char *msg) 540218893Sdim{ 541218893Sdim GIANT_REQUIRED; 542234353Sdim if ((m->flags & PG_BUSY) || (also_m_busy && m->busy)) { 543210008Srdivacky int s = splvm(); 544210008Srdivacky if ((m->flags & PG_BUSY) || (also_m_busy && m->busy)) { 545210008Srdivacky /* 546210008Srdivacky * Page is busy. Wait and retry. 547210008Srdivacky */ 548210008Srdivacky vm_page_flag_set(m, PG_WANTED | PG_REFERENCED); 549210008Srdivacky tsleep(m, PVM, msg, 0); 550210008Srdivacky } 551210008Srdivacky splx(s); 552210008Srdivacky return (TRUE); 553210008Srdivacky /* not reached */ 554210008Srdivacky } 555210008Srdivacky return (FALSE); 556210008Srdivacky} 557210008Srdivacky 558210008Srdivacky/* 559210008Srdivacky * vm_page_sleep_if_busy: 560210008Srdivacky * 561210008Srdivacky * Sleep and release the page queues lock if PG_BUSY is set or, 562210008Srdivacky * if also_m_busy is TRUE, busy is non-zero. Returns TRUE if the 563210008Srdivacky * thread slept and the page queues lock was released. 564210008Srdivacky * Otherwise, retains the page queues lock and returns FALSE. 565210008Srdivacky */ 566210008Srdivackyint 567210008Srdivackyvm_page_sleep_if_busy(vm_page_t m, int also_m_busy, const char *msg) 568218893Sdim{ 569218893Sdim 570218893Sdim mtx_assert(&vm_page_queue_mtx, MA_OWNED); 571218893Sdim if ((m->flags & PG_BUSY) || (also_m_busy && m->busy)) { 572210008Srdivacky vm_page_flag_set(m, PG_WANTED | PG_REFERENCED); 573210008Srdivacky msleep(m, &vm_page_queue_mtx, PDROP | PVM, msg, 0); 574210008Srdivacky return (TRUE); 575210008Srdivacky } 576210008Srdivacky return (FALSE); 577210008Srdivacky} 578210008Srdivacky 579210008Srdivacky/* 580210008Srdivacky * vm_page_dirty: 581234353Sdim * 582210008Srdivacky * make page all dirty 583210008Srdivacky */ 584210008Srdivackyvoid 585210008Srdivackyvm_page_dirty(vm_page_t m) 586218893Sdim{ 587218893Sdim KASSERT(m->queue - m->pc != PQ_CACHE, 588210008Srdivacky ("vm_page_dirty: page in cache!")); 589210008Srdivacky m->dirty = VM_PAGE_BITS_ALL; 590210008Srdivacky} 591210008Srdivacky 592210008Srdivacky/* 593210008Srdivacky * vm_page_undirty: 594210008Srdivacky * 595263508Sdim * Set page to not be dirty. Note: does not clear pmap modify bits 596263508Sdim */ 597234353Sdimvoid 598210008Srdivackyvm_page_undirty(vm_page_t m) 599210008Srdivacky{ 600210008Srdivacky m->dirty = 0; 601210008Srdivacky} 602210008Srdivacky 603210008Srdivacky/* 604210008Srdivacky * vm_page_insert: [ internal use only ] 605210008Srdivacky * 606210008Srdivacky * Inserts the given mem entry into the object and object list. 607218893Sdim * 608234353Sdim * The pagetables are not updated but will presumably fault the page 609210008Srdivacky * in if necessary, or if a kernel page the caller will at some point 610210008Srdivacky * enter the page into the kernel's pmap. We are not allowed to block 611210008Srdivacky * here so we *can't* do this anyway. 612210008Srdivacky * 613210008Srdivacky * The object and page must be locked, and must be splhigh. 614210008Srdivacky * This routine may not block. 615210008Srdivacky */ 616210008Srdivackyvoid 617210008Srdivackyvm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex) 618218893Sdim{ 619210008Srdivacky struct vm_page **bucket; 620210008Srdivacky 621210008Srdivacky GIANT_REQUIRED; 622210008Srdivacky 623210008Srdivacky if (m->object != NULL) 624221345Sdim panic("vm_page_insert: already inserted"); 625221345Sdim 626210008Srdivacky /* 627210008Srdivacky * Record the object/offset pair in this page 628210008Srdivacky */ 629210008Srdivacky m->object = object; 630239462Sdim m->pindex = pindex; 631221345Sdim 632210008Srdivacky /* 633210008Srdivacky * Insert it into the object_object/offset hash table 634210008Srdivacky */ 635210008Srdivacky bucket = &vm_page_buckets[vm_page_hash(object, pindex)]; 636210008Srdivacky mtx_lock_spin(&vm_page_buckets_mtx); 637210008Srdivacky m->hnext = *bucket; 638210008Srdivacky *bucket = m; 639210008Srdivacky mtx_unlock_spin(&vm_page_buckets_mtx); 640210008Srdivacky 641210008Srdivacky /* 642210008Srdivacky * Now link into the object's list of backed pages. 643210008Srdivacky */ 644210008Srdivacky TAILQ_INSERT_TAIL(&object->memq, m, listq); 645221345Sdim object->generation++; 646221345Sdim 647210008Srdivacky /* 648210008Srdivacky * show that the object has one more resident page. 649210008Srdivacky */ 650210008Srdivacky object->resident_page_count++; 651239462Sdim 652221345Sdim /* 653210008Srdivacky * Since we are inserting a new and possibly dirty page, 654210008Srdivacky * update the object's OBJ_WRITEABLE and OBJ_MIGHTBEDIRTY flags. 655210008Srdivacky */ 656210008Srdivacky if (m->flags & PG_WRITEABLE) 657210008Srdivacky vm_object_set_writeable_dirty(object); 658210008Srdivacky} 659210008Srdivacky 660210008Srdivacky/* 661210008Srdivacky * vm_page_remove: 662210008Srdivacky * NOTE: used by device pager as well -wfj 663210008Srdivacky * 664210008Srdivacky * Removes the given mem entry from the object/offset-page 665210008Srdivacky * table and the object page list, but do not invalidate/terminate 666210008Srdivacky * the backing store. 667210008Srdivacky * 668210008Srdivacky * The object and page must be locked, and at splhigh. 669210008Srdivacky * The underlying pmap entry (if any) is NOT removed here. 670210008Srdivacky * This routine may not block. 671210008Srdivacky */ 672void 673vm_page_remove(vm_page_t m) 674{ 675 vm_object_t object; 676 vm_page_t *bucket; 677 678 GIANT_REQUIRED; 679 680 if (m->object == NULL) 681 return; 682 683 if ((m->flags & PG_BUSY) == 0) { 684 panic("vm_page_remove: page not busy"); 685 } 686 687 /* 688 * Basically destroy the page. 689 */ 690 vm_page_wakeup(m); 691 692 object = m->object; 693 694 /* 695 * Remove from the object_object/offset hash table. The object 696 * must be on the hash queue, we will panic if it isn't 697 */ 698 bucket = &vm_page_buckets[vm_page_hash(m->object, m->pindex)]; 699 mtx_lock_spin(&vm_page_buckets_mtx); 700 while (*bucket != m) { 701 if (*bucket == NULL) 702 panic("vm_page_remove(): page not found in hash"); 703 bucket = &(*bucket)->hnext; 704 } 705 *bucket = m->hnext; 706 m->hnext = NULL; 707 mtx_unlock_spin(&vm_page_buckets_mtx); 708 709 /* 710 * Now remove from the object's list of backed pages. 711 */ 712 TAILQ_REMOVE(&object->memq, m, listq); 713 714 /* 715 * And show that the object has one fewer resident page. 716 */ 717 object->resident_page_count--; 718 object->generation++; 719 720 m->object = NULL; 721} 722 723/* 724 * vm_page_lookup: 725 * 726 * Returns the page associated with the object/offset 727 * pair specified; if none is found, NULL is returned. 728 * 729 * The object must be locked. No side effects. 730 * This routine may not block. 731 * This is a critical path routine 732 */ 733vm_page_t 734vm_page_lookup(vm_object_t object, vm_pindex_t pindex) 735{ 736 vm_page_t m; 737 struct vm_page **bucket; 738 739 /* 740 * Search the hash table for this object/offset pair 741 */ 742 bucket = &vm_page_buckets[vm_page_hash(object, pindex)]; 743 mtx_lock_spin(&vm_page_buckets_mtx); 744 for (m = *bucket; m != NULL; m = m->hnext) 745 if (m->object == object && m->pindex == pindex) 746 break; 747 mtx_unlock_spin(&vm_page_buckets_mtx); 748 return (m); 749} 750 751/* 752 * vm_page_rename: 753 * 754 * Move the given memory entry from its 755 * current object to the specified target object/offset. 756 * 757 * The object must be locked. 758 * This routine may not block. 759 * 760 * Note: this routine will raise itself to splvm(), the caller need not. 761 * 762 * Note: swap associated with the page must be invalidated by the move. We 763 * have to do this for several reasons: (1) we aren't freeing the 764 * page, (2) we are dirtying the page, (3) the VM system is probably 765 * moving the page from object A to B, and will then later move 766 * the backing store from A to B and we can't have a conflict. 767 * 768 * Note: we *always* dirty the page. It is necessary both for the 769 * fact that we moved it, and because we may be invalidating 770 * swap. If the page is on the cache, we have to deactivate it 771 * or vm_page_dirty() will panic. Dirty pages are not allowed 772 * on the cache. 773 */ 774void 775vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex) 776{ 777 int s; 778 779 s = splvm(); 780 vm_page_lock_queues(); 781 vm_page_remove(m); 782 vm_page_insert(m, new_object, new_pindex); 783 if (m->queue - m->pc == PQ_CACHE) 784 vm_page_deactivate(m); 785 vm_page_dirty(m); 786 vm_page_unlock_queues(); 787 splx(s); 788} 789 790/* 791 * vm_page_select_cache: 792 * 793 * Find a page on the cache queue with color optimization. As pages 794 * might be found, but not applicable, they are deactivated. This 795 * keeps us from using potentially busy cached pages. 796 * 797 * This routine must be called at splvm(). 798 * This routine may not block. 799 */ 800static vm_page_t 801vm_page_select_cache(vm_object_t object, vm_pindex_t pindex) 802{ 803 vm_page_t m; 804 805 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 806 while (TRUE) { 807 m = vm_pageq_find( 808 PQ_CACHE, 809 (pindex + object->pg_color) & PQ_L2_MASK, 810 FALSE 811 ); 812 if (m && ((m->flags & (PG_BUSY|PG_UNMANAGED)) || m->busy || 813 m->hold_count || m->wire_count)) { 814 vm_page_deactivate(m); 815 continue; 816 } 817 return m; 818 } 819} 820 821/* 822 * vm_page_select_free: 823 * 824 * Find a free or zero page, with specified preference. 825 * 826 * This routine must be called at splvm(). 827 * This routine may not block. 828 */ 829static __inline vm_page_t 830vm_page_select_free(vm_object_t object, vm_pindex_t pindex, boolean_t prefer_zero) 831{ 832 vm_page_t m; 833 834 m = vm_pageq_find( 835 PQ_FREE, 836 (pindex + object->pg_color) & PQ_L2_MASK, 837 prefer_zero 838 ); 839 return (m); 840} 841 842/* 843 * vm_page_alloc: 844 * 845 * Allocate and return a memory cell associated 846 * with this VM object/offset pair. 847 * 848 * page_req classes: 849 * VM_ALLOC_NORMAL normal process request 850 * VM_ALLOC_SYSTEM system *really* needs a page 851 * VM_ALLOC_INTERRUPT interrupt time request 852 * VM_ALLOC_ZERO zero page 853 * 854 * This routine may not block. 855 * 856 * Additional special handling is required when called from an 857 * interrupt (VM_ALLOC_INTERRUPT). We are not allowed to mess with 858 * the page cache in this case. 859 */ 860vm_page_t 861vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req) 862{ 863 vm_page_t m = NULL; 864 int page_req, s; 865 866 GIANT_REQUIRED; 867 868 KASSERT(!vm_page_lookup(object, pindex), 869 ("vm_page_alloc: page already allocated")); 870 871 page_req = req & VM_ALLOC_CLASS_MASK; 872 873 /* 874 * The pager is allowed to eat deeper into the free page list. 875 */ 876 if ((curproc == pageproc) && (page_req != VM_ALLOC_INTERRUPT)) { 877 page_req = VM_ALLOC_SYSTEM; 878 }; 879 880 s = splvm(); 881loop: 882 mtx_lock_spin(&vm_page_queue_free_mtx); 883 if (cnt.v_free_count > cnt.v_free_reserved) { 884 /* 885 * Allocate from the free queue if there are plenty of pages 886 * in it. 887 */ 888 m = vm_page_select_free(object, pindex, 889 (req & VM_ALLOC_ZERO) != 0); 890 } else if ( 891 (page_req == VM_ALLOC_SYSTEM && 892 cnt.v_cache_count == 0 && 893 cnt.v_free_count > cnt.v_interrupt_free_min) || 894 (page_req == VM_ALLOC_INTERRUPT && cnt.v_free_count > 0) 895 ) { 896 /* 897 * Interrupt or system, dig deeper into the free list. 898 */ 899 m = vm_page_select_free(object, pindex, FALSE); 900 } else if (page_req != VM_ALLOC_INTERRUPT) { 901 mtx_unlock_spin(&vm_page_queue_free_mtx); 902 /* 903 * Allocatable from cache (non-interrupt only). On success, 904 * we must free the page and try again, thus ensuring that 905 * cnt.v_*_free_min counters are replenished. 906 */ 907 vm_page_lock_queues(); 908 if ((m = vm_page_select_cache(object, pindex)) == NULL) { 909 vm_page_unlock_queues(); 910 splx(s); 911#if defined(DIAGNOSTIC) 912 if (cnt.v_cache_count > 0) 913 printf("vm_page_alloc(NORMAL): missing pages on cache queue: %d\n", cnt.v_cache_count); 914#endif 915 vm_pageout_deficit++; 916 pagedaemon_wakeup(); 917 return (NULL); 918 } 919 KASSERT(m->dirty == 0, ("Found dirty cache page %p", m)); 920 vm_page_busy(m); 921 vm_page_protect(m, VM_PROT_NONE); 922 vm_page_free(m); 923 vm_page_unlock_queues(); 924 goto loop; 925 } else { 926 /* 927 * Not allocatable from cache from interrupt, give up. 928 */ 929 mtx_unlock_spin(&vm_page_queue_free_mtx); 930 splx(s); 931 vm_pageout_deficit++; 932 pagedaemon_wakeup(); 933 return (NULL); 934 } 935 936 /* 937 * At this point we had better have found a good page. 938 */ 939 940 KASSERT( 941 m != NULL, 942 ("vm_page_alloc(): missing page on free queue\n") 943 ); 944 945 /* 946 * Remove from free queue 947 */ 948 949 vm_pageq_remove_nowakeup(m); 950 951 /* 952 * Initialize structure. Only the PG_ZERO flag is inherited. 953 */ 954 if (m->flags & PG_ZERO) { 955 vm_page_zero_count--; 956 m->flags = PG_ZERO | PG_BUSY; 957 } else { 958 m->flags = PG_BUSY; 959 } 960 if (req & VM_ALLOC_WIRED) { 961 cnt.v_wire_count++; 962 m->wire_count = 1; 963 } else 964 m->wire_count = 0; 965 m->hold_count = 0; 966 m->act_count = 0; 967 m->busy = 0; 968 m->valid = 0; 969 KASSERT(m->dirty == 0, ("vm_page_alloc: free/cache page %p was dirty", m)); 970 mtx_unlock_spin(&vm_page_queue_free_mtx); 971 972 /* 973 * vm_page_insert() is safe prior to the splx(). Note also that 974 * inserting a page here does not insert it into the pmap (which 975 * could cause us to block allocating memory). We cannot block 976 * anywhere. 977 */ 978 vm_page_insert(m, object, pindex); 979 980 /* 981 * Don't wakeup too often - wakeup the pageout daemon when 982 * we would be nearly out of memory. 983 */ 984 if (vm_paging_needed()) 985 pagedaemon_wakeup(); 986 987 splx(s); 988 return (m); 989} 990 991/* 992 * vm_wait: (also see VM_WAIT macro) 993 * 994 * Block until free pages are available for allocation 995 * - Called in various places before memory allocations. 996 */ 997void 998vm_wait(void) 999{ 1000 int s; 1001 1002 s = splvm(); 1003 if (curproc == pageproc) { 1004 vm_pageout_pages_needed = 1; 1005 tsleep(&vm_pageout_pages_needed, PSWP, "VMWait", 0); 1006 } else { 1007 if (!vm_pages_needed) { 1008 vm_pages_needed = 1; 1009 wakeup(&vm_pages_needed); 1010 } 1011 tsleep(&cnt.v_free_count, PVM, "vmwait", 0); 1012 } 1013 splx(s); 1014} 1015 1016/* 1017 * vm_waitpfault: (also see VM_WAITPFAULT macro) 1018 * 1019 * Block until free pages are available for allocation 1020 * - Called only in vm_fault so that processes page faulting 1021 * can be easily tracked. 1022 * - Sleeps at a lower priority than vm_wait() so that vm_wait()ing 1023 * processes will be able to grab memory first. Do not change 1024 * this balance without careful testing first. 1025 */ 1026void 1027vm_waitpfault(void) 1028{ 1029 int s; 1030 1031 s = splvm(); 1032 if (!vm_pages_needed) { 1033 vm_pages_needed = 1; 1034 wakeup(&vm_pages_needed); 1035 } 1036 tsleep(&cnt.v_free_count, PUSER, "pfault", 0); 1037 splx(s); 1038} 1039 1040/* 1041 * vm_page_activate: 1042 * 1043 * Put the specified page on the active list (if appropriate). 1044 * Ensure that act_count is at least ACT_INIT but do not otherwise 1045 * mess with it. 1046 * 1047 * The page queues must be locked. 1048 * This routine may not block. 1049 */ 1050void 1051vm_page_activate(vm_page_t m) 1052{ 1053 int s; 1054 1055 GIANT_REQUIRED; 1056 s = splvm(); 1057 if (m->queue != PQ_ACTIVE) { 1058 if ((m->queue - m->pc) == PQ_CACHE) 1059 cnt.v_reactivated++; 1060 vm_pageq_remove(m); 1061 if (m->wire_count == 0 && (m->flags & PG_UNMANAGED) == 0) { 1062 if (m->act_count < ACT_INIT) 1063 m->act_count = ACT_INIT; 1064 vm_pageq_enqueue(PQ_ACTIVE, m); 1065 } 1066 } else { 1067 if (m->act_count < ACT_INIT) 1068 m->act_count = ACT_INIT; 1069 } 1070 splx(s); 1071} 1072 1073/* 1074 * vm_page_free_wakeup: 1075 * 1076 * Helper routine for vm_page_free_toq() and vm_page_cache(). This 1077 * routine is called when a page has been added to the cache or free 1078 * queues. 1079 * 1080 * This routine may not block. 1081 * This routine must be called at splvm() 1082 */ 1083static __inline void 1084vm_page_free_wakeup(void) 1085{ 1086 /* 1087 * if pageout daemon needs pages, then tell it that there are 1088 * some free. 1089 */ 1090 if (vm_pageout_pages_needed && 1091 cnt.v_cache_count + cnt.v_free_count >= cnt.v_pageout_free_min) { 1092 wakeup(&vm_pageout_pages_needed); 1093 vm_pageout_pages_needed = 0; 1094 } 1095 /* 1096 * wakeup processes that are waiting on memory if we hit a 1097 * high water mark. And wakeup scheduler process if we have 1098 * lots of memory. this process will swapin processes. 1099 */ 1100 if (vm_pages_needed && !vm_page_count_min()) { 1101 vm_pages_needed = 0; 1102 wakeup(&cnt.v_free_count); 1103 } 1104} 1105 1106/* 1107 * vm_page_free_toq: 1108 * 1109 * Returns the given page to the PQ_FREE list, 1110 * disassociating it with any VM object. 1111 * 1112 * Object and page must be locked prior to entry. 1113 * This routine may not block. 1114 */ 1115 1116void 1117vm_page_free_toq(vm_page_t m) 1118{ 1119 int s; 1120 struct vpgqueues *pq; 1121 vm_object_t object = m->object; 1122 1123 GIANT_REQUIRED; 1124 s = splvm(); 1125 cnt.v_tfree++; 1126 1127 if (m->busy || ((m->queue - m->pc) == PQ_FREE)) { 1128 printf( 1129 "vm_page_free: pindex(%lu), busy(%d), PG_BUSY(%d), hold(%d)\n", 1130 (u_long)m->pindex, m->busy, (m->flags & PG_BUSY) ? 1 : 0, 1131 m->hold_count); 1132 if ((m->queue - m->pc) == PQ_FREE) 1133 panic("vm_page_free: freeing free page"); 1134 else 1135 panic("vm_page_free: freeing busy page"); 1136 } 1137 1138 /* 1139 * unqueue, then remove page. Note that we cannot destroy 1140 * the page here because we do not want to call the pager's 1141 * callback routine until after we've put the page on the 1142 * appropriate free queue. 1143 */ 1144 vm_pageq_remove_nowakeup(m); 1145 vm_page_remove(m); 1146 1147 /* 1148 * If fictitious remove object association and 1149 * return, otherwise delay object association removal. 1150 */ 1151 if ((m->flags & PG_FICTITIOUS) != 0) { 1152 splx(s); 1153 return; 1154 } 1155 1156 m->valid = 0; 1157 vm_page_undirty(m); 1158 1159 if (m->wire_count != 0) { 1160 if (m->wire_count > 1) { 1161 panic("vm_page_free: invalid wire count (%d), pindex: 0x%lx", 1162 m->wire_count, (long)m->pindex); 1163 } 1164 panic("vm_page_free: freeing wired page\n"); 1165 } 1166 1167 /* 1168 * If we've exhausted the object's resident pages we want to free 1169 * it up. 1170 */ 1171 if (object && 1172 (object->type == OBJT_VNODE) && 1173 ((object->flags & OBJ_DEAD) == 0) 1174 ) { 1175 struct vnode *vp = (struct vnode *)object->handle; 1176 1177 if (vp && VSHOULDFREE(vp)) 1178 vfree(vp); 1179 } 1180 1181 /* 1182 * Clear the UNMANAGED flag when freeing an unmanaged page. 1183 */ 1184 if (m->flags & PG_UNMANAGED) { 1185 m->flags &= ~PG_UNMANAGED; 1186 } else { 1187#ifdef __alpha__ 1188 pmap_page_is_free(m); 1189#endif 1190 } 1191 1192 if (m->hold_count != 0) { 1193 m->flags &= ~PG_ZERO; 1194 m->queue = PQ_HOLD; 1195 } else 1196 m->queue = PQ_FREE + m->pc; 1197 pq = &vm_page_queues[m->queue]; 1198 mtx_lock_spin(&vm_page_queue_free_mtx); 1199 pq->lcnt++; 1200 ++(*pq->cnt); 1201 1202 /* 1203 * Put zero'd pages on the end ( where we look for zero'd pages 1204 * first ) and non-zerod pages at the head. 1205 */ 1206 if (m->flags & PG_ZERO) { 1207 TAILQ_INSERT_TAIL(&pq->pl, m, pageq); 1208 ++vm_page_zero_count; 1209 } else { 1210 TAILQ_INSERT_HEAD(&pq->pl, m, pageq); 1211 } 1212 mtx_unlock_spin(&vm_page_queue_free_mtx); 1213 vm_page_free_wakeup(); 1214 splx(s); 1215} 1216 1217/* 1218 * vm_page_unmanage: 1219 * 1220 * Prevent PV management from being done on the page. The page is 1221 * removed from the paging queues as if it were wired, and as a 1222 * consequence of no longer being managed the pageout daemon will not 1223 * touch it (since there is no way to locate the pte mappings for the 1224 * page). madvise() calls that mess with the pmap will also no longer 1225 * operate on the page. 1226 * 1227 * Beyond that the page is still reasonably 'normal'. Freeing the page 1228 * will clear the flag. 1229 * 1230 * This routine is used by OBJT_PHYS objects - objects using unswappable 1231 * physical memory as backing store rather then swap-backed memory and 1232 * will eventually be extended to support 4MB unmanaged physical 1233 * mappings. 1234 */ 1235void 1236vm_page_unmanage(vm_page_t m) 1237{ 1238 int s; 1239 1240 s = splvm(); 1241 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 1242 if ((m->flags & PG_UNMANAGED) == 0) { 1243 if (m->wire_count == 0) 1244 vm_pageq_remove(m); 1245 } 1246 vm_page_flag_set(m, PG_UNMANAGED); 1247 splx(s); 1248} 1249 1250/* 1251 * vm_page_wire: 1252 * 1253 * Mark this page as wired down by yet 1254 * another map, removing it from paging queues 1255 * as necessary. 1256 * 1257 * The page queues must be locked. 1258 * This routine may not block. 1259 */ 1260void 1261vm_page_wire(vm_page_t m) 1262{ 1263 int s; 1264 1265 /* 1266 * Only bump the wire statistics if the page is not already wired, 1267 * and only unqueue the page if it is on some queue (if it is unmanaged 1268 * it is already off the queues). 1269 */ 1270 s = splvm(); 1271 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 1272 if (m->wire_count == 0) { 1273 if ((m->flags & PG_UNMANAGED) == 0) 1274 vm_pageq_remove(m); 1275 cnt.v_wire_count++; 1276 } 1277 m->wire_count++; 1278 KASSERT(m->wire_count != 0, ("vm_page_wire: wire_count overflow m=%p", m)); 1279 splx(s); 1280} 1281 1282/* 1283 * vm_page_unwire: 1284 * 1285 * Release one wiring of this page, potentially 1286 * enabling it to be paged again. 1287 * 1288 * Many pages placed on the inactive queue should actually go 1289 * into the cache, but it is difficult to figure out which. What 1290 * we do instead, if the inactive target is well met, is to put 1291 * clean pages at the head of the inactive queue instead of the tail. 1292 * This will cause them to be moved to the cache more quickly and 1293 * if not actively re-referenced, freed more quickly. If we just 1294 * stick these pages at the end of the inactive queue, heavy filesystem 1295 * meta-data accesses can cause an unnecessary paging load on memory bound 1296 * processes. This optimization causes one-time-use metadata to be 1297 * reused more quickly. 1298 * 1299 * BUT, if we are in a low-memory situation we have no choice but to 1300 * put clean pages on the cache queue. 1301 * 1302 * A number of routines use vm_page_unwire() to guarantee that the page 1303 * will go into either the inactive or active queues, and will NEVER 1304 * be placed in the cache - for example, just after dirtying a page. 1305 * dirty pages in the cache are not allowed. 1306 * 1307 * The page queues must be locked. 1308 * This routine may not block. 1309 */ 1310void 1311vm_page_unwire(vm_page_t m, int activate) 1312{ 1313 int s; 1314 1315 s = splvm(); 1316 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 1317 if (m->wire_count > 0) { 1318 m->wire_count--; 1319 if (m->wire_count == 0) { 1320 cnt.v_wire_count--; 1321 if (m->flags & PG_UNMANAGED) { 1322 ; 1323 } else if (activate) 1324 vm_pageq_enqueue(PQ_ACTIVE, m); 1325 else { 1326 vm_page_flag_clear(m, PG_WINATCFLS); 1327 vm_pageq_enqueue(PQ_INACTIVE, m); 1328 } 1329 } 1330 } else { 1331 panic("vm_page_unwire: invalid wire count: %d\n", m->wire_count); 1332 } 1333 splx(s); 1334} 1335 1336 1337/* 1338 * Move the specified page to the inactive queue. If the page has 1339 * any associated swap, the swap is deallocated. 1340 * 1341 * Normally athead is 0 resulting in LRU operation. athead is set 1342 * to 1 if we want this page to be 'as if it were placed in the cache', 1343 * except without unmapping it from the process address space. 1344 * 1345 * This routine may not block. 1346 */ 1347static __inline void 1348_vm_page_deactivate(vm_page_t m, int athead) 1349{ 1350 int s; 1351 1352 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 1353 /* 1354 * Ignore if already inactive. 1355 */ 1356 if (m->queue == PQ_INACTIVE) 1357 return; 1358 1359 s = splvm(); 1360 if (m->wire_count == 0 && (m->flags & PG_UNMANAGED) == 0) { 1361 if ((m->queue - m->pc) == PQ_CACHE) 1362 cnt.v_reactivated++; 1363 vm_page_flag_clear(m, PG_WINATCFLS); 1364 vm_pageq_remove(m); 1365 if (athead) 1366 TAILQ_INSERT_HEAD(&vm_page_queues[PQ_INACTIVE].pl, m, pageq); 1367 else 1368 TAILQ_INSERT_TAIL(&vm_page_queues[PQ_INACTIVE].pl, m, pageq); 1369 m->queue = PQ_INACTIVE; 1370 vm_page_queues[PQ_INACTIVE].lcnt++; 1371 cnt.v_inactive_count++; 1372 } 1373 splx(s); 1374} 1375 1376void 1377vm_page_deactivate(vm_page_t m) 1378{ 1379 _vm_page_deactivate(m, 0); 1380} 1381 1382/* 1383 * vm_page_try_to_cache: 1384 * 1385 * Returns 0 on failure, 1 on success 1386 */ 1387int 1388vm_page_try_to_cache(vm_page_t m) 1389{ 1390 1391 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 1392 if (m->dirty || m->hold_count || m->busy || m->wire_count || 1393 (m->flags & (PG_BUSY|PG_UNMANAGED))) { 1394 return (0); 1395 } 1396 vm_page_test_dirty(m); 1397 if (m->dirty) 1398 return (0); 1399 vm_page_cache(m); 1400 return (1); 1401} 1402 1403/* 1404 * vm_page_try_to_free() 1405 * 1406 * Attempt to free the page. If we cannot free it, we do nothing. 1407 * 1 is returned on success, 0 on failure. 1408 */ 1409int 1410vm_page_try_to_free(vm_page_t m) 1411{ 1412 1413 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 1414 if (m->dirty || m->hold_count || m->busy || m->wire_count || 1415 (m->flags & (PG_BUSY|PG_UNMANAGED))) { 1416 return (0); 1417 } 1418 vm_page_test_dirty(m); 1419 if (m->dirty) 1420 return (0); 1421 vm_page_busy(m); 1422 vm_page_protect(m, VM_PROT_NONE); 1423 vm_page_free(m); 1424 return (1); 1425} 1426 1427/* 1428 * vm_page_cache 1429 * 1430 * Put the specified page onto the page cache queue (if appropriate). 1431 * 1432 * This routine may not block. 1433 */ 1434void 1435vm_page_cache(vm_page_t m) 1436{ 1437 int s; 1438 1439 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 1440 if ((m->flags & (PG_BUSY|PG_UNMANAGED)) || m->busy || m->wire_count) { 1441 printf("vm_page_cache: attempting to cache busy page\n"); 1442 return; 1443 } 1444 if ((m->queue - m->pc) == PQ_CACHE) 1445 return; 1446 1447 /* 1448 * Remove all pmaps and indicate that the page is not 1449 * writeable or mapped. 1450 */ 1451 vm_page_protect(m, VM_PROT_NONE); 1452 if (m->dirty != 0) { 1453 panic("vm_page_cache: caching a dirty page, pindex: %ld", 1454 (long)m->pindex); 1455 } 1456 s = splvm(); 1457 vm_pageq_remove_nowakeup(m); 1458 vm_pageq_enqueue(PQ_CACHE + m->pc, m); 1459 vm_page_free_wakeup(); 1460 splx(s); 1461} 1462 1463/* 1464 * vm_page_dontneed 1465 * 1466 * Cache, deactivate, or do nothing as appropriate. This routine 1467 * is typically used by madvise() MADV_DONTNEED. 1468 * 1469 * Generally speaking we want to move the page into the cache so 1470 * it gets reused quickly. However, this can result in a silly syndrome 1471 * due to the page recycling too quickly. Small objects will not be 1472 * fully cached. On the otherhand, if we move the page to the inactive 1473 * queue we wind up with a problem whereby very large objects 1474 * unnecessarily blow away our inactive and cache queues. 1475 * 1476 * The solution is to move the pages based on a fixed weighting. We 1477 * either leave them alone, deactivate them, or move them to the cache, 1478 * where moving them to the cache has the highest weighting. 1479 * By forcing some pages into other queues we eventually force the 1480 * system to balance the queues, potentially recovering other unrelated 1481 * space from active. The idea is to not force this to happen too 1482 * often. 1483 */ 1484void 1485vm_page_dontneed(vm_page_t m) 1486{ 1487 static int dnweight; 1488 int dnw; 1489 int head; 1490 1491 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 1492 dnw = ++dnweight; 1493 1494 /* 1495 * occassionally leave the page alone 1496 */ 1497 if ((dnw & 0x01F0) == 0 || 1498 m->queue == PQ_INACTIVE || 1499 m->queue - m->pc == PQ_CACHE 1500 ) { 1501 if (m->act_count >= ACT_INIT) 1502 --m->act_count; 1503 return; 1504 } 1505 1506 if (m->dirty == 0) 1507 vm_page_test_dirty(m); 1508 1509 if (m->dirty || (dnw & 0x0070) == 0) { 1510 /* 1511 * Deactivate the page 3 times out of 32. 1512 */ 1513 head = 0; 1514 } else { 1515 /* 1516 * Cache the page 28 times out of every 32. Note that 1517 * the page is deactivated instead of cached, but placed 1518 * at the head of the queue instead of the tail. 1519 */ 1520 head = 1; 1521 } 1522 _vm_page_deactivate(m, head); 1523} 1524 1525/* 1526 * Grab a page, waiting until we are waken up due to the page 1527 * changing state. We keep on waiting, if the page continues 1528 * to be in the object. If the page doesn't exist, allocate it. 1529 * 1530 * This routine may block. 1531 */ 1532vm_page_t 1533vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags) 1534{ 1535 vm_page_t m; 1536 int s, generation; 1537 1538 GIANT_REQUIRED; 1539retrylookup: 1540 if ((m = vm_page_lookup(object, pindex)) != NULL) { 1541 if (m->busy || (m->flags & PG_BUSY)) { 1542 generation = object->generation; 1543 1544 s = splvm(); 1545 while ((object->generation == generation) && 1546 (m->busy || (m->flags & PG_BUSY))) { 1547 vm_page_flag_set(m, PG_WANTED | PG_REFERENCED); 1548 tsleep(m, PVM, "pgrbwt", 0); 1549 if ((allocflags & VM_ALLOC_RETRY) == 0) { 1550 splx(s); 1551 return NULL; 1552 } 1553 } 1554 splx(s); 1555 goto retrylookup; 1556 } else { 1557 vm_page_lock_queues(); 1558 if (allocflags & VM_ALLOC_WIRED) 1559 vm_page_wire(m); 1560 vm_page_busy(m); 1561 vm_page_unlock_queues(); 1562 return m; 1563 } 1564 } 1565 1566 m = vm_page_alloc(object, pindex, allocflags & ~VM_ALLOC_RETRY); 1567 if (m == NULL) { 1568 VM_WAIT; 1569 if ((allocflags & VM_ALLOC_RETRY) == 0) 1570 return NULL; 1571 goto retrylookup; 1572 } 1573 1574 return m; 1575} 1576 1577/* 1578 * Mapping function for valid bits or for dirty bits in 1579 * a page. May not block. 1580 * 1581 * Inputs are required to range within a page. 1582 */ 1583__inline int 1584vm_page_bits(int base, int size) 1585{ 1586 int first_bit; 1587 int last_bit; 1588 1589 KASSERT( 1590 base + size <= PAGE_SIZE, 1591 ("vm_page_bits: illegal base/size %d/%d", base, size) 1592 ); 1593 1594 if (size == 0) /* handle degenerate case */ 1595 return (0); 1596 1597 first_bit = base >> DEV_BSHIFT; 1598 last_bit = (base + size - 1) >> DEV_BSHIFT; 1599 1600 return ((2 << last_bit) - (1 << first_bit)); 1601} 1602 1603/* 1604 * vm_page_set_validclean: 1605 * 1606 * Sets portions of a page valid and clean. The arguments are expected 1607 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive 1608 * of any partial chunks touched by the range. The invalid portion of 1609 * such chunks will be zero'd. 1610 * 1611 * This routine may not block. 1612 * 1613 * (base + size) must be less then or equal to PAGE_SIZE. 1614 */ 1615void 1616vm_page_set_validclean(vm_page_t m, int base, int size) 1617{ 1618 int pagebits; 1619 int frag; 1620 int endoff; 1621 1622 GIANT_REQUIRED; 1623 if (size == 0) /* handle degenerate case */ 1624 return; 1625 1626 /* 1627 * If the base is not DEV_BSIZE aligned and the valid 1628 * bit is clear, we have to zero out a portion of the 1629 * first block. 1630 */ 1631 if ((frag = base & ~(DEV_BSIZE - 1)) != base && 1632 (m->valid & (1 << (base >> DEV_BSHIFT))) == 0) 1633 pmap_zero_page_area(m, frag, base - frag); 1634 1635 /* 1636 * If the ending offset is not DEV_BSIZE aligned and the 1637 * valid bit is clear, we have to zero out a portion of 1638 * the last block. 1639 */ 1640 endoff = base + size; 1641 if ((frag = endoff & ~(DEV_BSIZE - 1)) != endoff && 1642 (m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0) 1643 pmap_zero_page_area(m, endoff, 1644 DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); 1645 1646 /* 1647 * Set valid, clear dirty bits. If validating the entire 1648 * page we can safely clear the pmap modify bit. We also 1649 * use this opportunity to clear the PG_NOSYNC flag. If a process 1650 * takes a write fault on a MAP_NOSYNC memory area the flag will 1651 * be set again. 1652 * 1653 * We set valid bits inclusive of any overlap, but we can only 1654 * clear dirty bits for DEV_BSIZE chunks that are fully within 1655 * the range. 1656 */ 1657 pagebits = vm_page_bits(base, size); 1658 m->valid |= pagebits; 1659#if 0 /* NOT YET */ 1660 if ((frag = base & (DEV_BSIZE - 1)) != 0) { 1661 frag = DEV_BSIZE - frag; 1662 base += frag; 1663 size -= frag; 1664 if (size < 0) 1665 size = 0; 1666 } 1667 pagebits = vm_page_bits(base, size & (DEV_BSIZE - 1)); 1668#endif 1669 m->dirty &= ~pagebits; 1670 if (base == 0 && size == PAGE_SIZE) { 1671 pmap_clear_modify(m); 1672 vm_page_flag_clear(m, PG_NOSYNC); 1673 } 1674} 1675 1676#if 0 1677 1678void 1679vm_page_set_dirty(vm_page_t m, int base, int size) 1680{ 1681 m->dirty |= vm_page_bits(base, size); 1682} 1683 1684#endif 1685 1686void 1687vm_page_clear_dirty(vm_page_t m, int base, int size) 1688{ 1689 GIANT_REQUIRED; 1690 m->dirty &= ~vm_page_bits(base, size); 1691} 1692 1693/* 1694 * vm_page_set_invalid: 1695 * 1696 * Invalidates DEV_BSIZE'd chunks within a page. Both the 1697 * valid and dirty bits for the effected areas are cleared. 1698 * 1699 * May not block. 1700 */ 1701void 1702vm_page_set_invalid(vm_page_t m, int base, int size) 1703{ 1704 int bits; 1705 1706 GIANT_REQUIRED; 1707 bits = vm_page_bits(base, size); 1708 m->valid &= ~bits; 1709 m->dirty &= ~bits; 1710 m->object->generation++; 1711} 1712 1713/* 1714 * vm_page_zero_invalid() 1715 * 1716 * The kernel assumes that the invalid portions of a page contain 1717 * garbage, but such pages can be mapped into memory by user code. 1718 * When this occurs, we must zero out the non-valid portions of the 1719 * page so user code sees what it expects. 1720 * 1721 * Pages are most often semi-valid when the end of a file is mapped 1722 * into memory and the file's size is not page aligned. 1723 */ 1724void 1725vm_page_zero_invalid(vm_page_t m, boolean_t setvalid) 1726{ 1727 int b; 1728 int i; 1729 1730 /* 1731 * Scan the valid bits looking for invalid sections that 1732 * must be zerod. Invalid sub-DEV_BSIZE'd areas ( where the 1733 * valid bit may be set ) have already been zerod by 1734 * vm_page_set_validclean(). 1735 */ 1736 for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) { 1737 if (i == (PAGE_SIZE / DEV_BSIZE) || 1738 (m->valid & (1 << i)) 1739 ) { 1740 if (i > b) { 1741 pmap_zero_page_area(m, 1742 b << DEV_BSHIFT, (i - b) << DEV_BSHIFT); 1743 } 1744 b = i + 1; 1745 } 1746 } 1747 1748 /* 1749 * setvalid is TRUE when we can safely set the zero'd areas 1750 * as being valid. We can do this if there are no cache consistancy 1751 * issues. e.g. it is ok to do with UFS, but not ok to do with NFS. 1752 */ 1753 if (setvalid) 1754 m->valid = VM_PAGE_BITS_ALL; 1755} 1756 1757/* 1758 * vm_page_is_valid: 1759 * 1760 * Is (partial) page valid? Note that the case where size == 0 1761 * will return FALSE in the degenerate case where the page is 1762 * entirely invalid, and TRUE otherwise. 1763 * 1764 * May not block. 1765 */ 1766int 1767vm_page_is_valid(vm_page_t m, int base, int size) 1768{ 1769 int bits = vm_page_bits(base, size); 1770 1771 if (m->valid && ((m->valid & bits) == bits)) 1772 return 1; 1773 else 1774 return 0; 1775} 1776 1777/* 1778 * update dirty bits from pmap/mmu. May not block. 1779 */ 1780void 1781vm_page_test_dirty(vm_page_t m) 1782{ 1783 if ((m->dirty != VM_PAGE_BITS_ALL) && pmap_is_modified(m)) { 1784 vm_page_dirty(m); 1785 } 1786} 1787 1788int so_zerocp_fullpage = 0; 1789 1790void 1791vm_page_cowfault(vm_page_t m) 1792{ 1793 vm_page_t mnew; 1794 vm_object_t object; 1795 vm_pindex_t pindex; 1796 1797 object = m->object; 1798 pindex = m->pindex; 1799 vm_page_busy(m); 1800 1801 retry_alloc: 1802 vm_page_remove(m); 1803 mnew = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 1804 if (mnew == NULL) { 1805 vm_page_insert(m, object, pindex); 1806 VM_WAIT; 1807 goto retry_alloc; 1808 } 1809 1810 if (m->cow == 0) { 1811 /* 1812 * check to see if we raced with an xmit complete when 1813 * waiting to allocate a page. If so, put things back 1814 * the way they were 1815 */ 1816 vm_page_busy(mnew); 1817 vm_page_free(mnew); 1818 vm_page_insert(m, object, pindex); 1819 } else { /* clear COW & copy page */ 1820 if (so_zerocp_fullpage) { 1821 mnew->valid = VM_PAGE_BITS_ALL; 1822 } else { 1823 vm_page_copy(m, mnew); 1824 } 1825 vm_page_dirty(mnew); 1826 vm_page_flag_clear(mnew, PG_BUSY); 1827 } 1828} 1829 1830void 1831vm_page_cowclear(vm_page_t m) 1832{ 1833 1834 /* XXX KDM find out if giant is required here. */ 1835 GIANT_REQUIRED; 1836 if (m->cow) { 1837 atomic_subtract_int(&m->cow, 1); 1838 /* 1839 * let vm_fault add back write permission lazily 1840 */ 1841 } 1842 /* 1843 * sf_buf_free() will free the page, so we needn't do it here 1844 */ 1845} 1846 1847void 1848vm_page_cowsetup(vm_page_t m) 1849{ 1850 /* XXX KDM find out if giant is required here */ 1851 GIANT_REQUIRED; 1852 atomic_add_int(&m->cow, 1); 1853 vm_page_protect(m, VM_PROT_READ); 1854} 1855 1856#include "opt_ddb.h" 1857#ifdef DDB 1858#include <sys/kernel.h> 1859 1860#include <ddb/ddb.h> 1861 1862DB_SHOW_COMMAND(page, vm_page_print_page_info) 1863{ 1864 db_printf("cnt.v_free_count: %d\n", cnt.v_free_count); 1865 db_printf("cnt.v_cache_count: %d\n", cnt.v_cache_count); 1866 db_printf("cnt.v_inactive_count: %d\n", cnt.v_inactive_count); 1867 db_printf("cnt.v_active_count: %d\n", cnt.v_active_count); 1868 db_printf("cnt.v_wire_count: %d\n", cnt.v_wire_count); 1869 db_printf("cnt.v_free_reserved: %d\n", cnt.v_free_reserved); 1870 db_printf("cnt.v_free_min: %d\n", cnt.v_free_min); 1871 db_printf("cnt.v_free_target: %d\n", cnt.v_free_target); 1872 db_printf("cnt.v_cache_min: %d\n", cnt.v_cache_min); 1873 db_printf("cnt.v_inactive_target: %d\n", cnt.v_inactive_target); 1874} 1875 1876DB_SHOW_COMMAND(pageq, vm_page_print_pageq_info) 1877{ 1878 int i; 1879 db_printf("PQ_FREE:"); 1880 for (i = 0; i < PQ_L2_SIZE; i++) { 1881 db_printf(" %d", vm_page_queues[PQ_FREE + i].lcnt); 1882 } 1883 db_printf("\n"); 1884 1885 db_printf("PQ_CACHE:"); 1886 for (i = 0; i < PQ_L2_SIZE; i++) { 1887 db_printf(" %d", vm_page_queues[PQ_CACHE + i].lcnt); 1888 } 1889 db_printf("\n"); 1890 1891 db_printf("PQ_ACTIVE: %d, PQ_INACTIVE: %d\n", 1892 vm_page_queues[PQ_ACTIVE].lcnt, 1893 vm_page_queues[PQ_INACTIVE].lcnt); 1894} 1895#endif /* DDB */ 1896