4 * Copyright (c) 1991 Regents of the University of California.
7 * This code is derived from software contributed to Berkeley by
8 * The Mach Operating System project at Carnegie-Mellon University.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * from: @(#)vm_page.c 7.4 (Berkeley) 5/7/91
39 * $FreeBSD: src/sys/vm/vm_page.c,v 1.147.2.18 2002/03/10 05:03:19 alc Exp $
40 * $DragonFly: src/sys/vm/vm_page.c,v 1.40 2008/08/25 17:01:42 dillon Exp $
44 * Copyright (c) 1987, 1990 Carnegie-Mellon University.
45 * All rights reserved.
47 * Authors: Avadis Tevanian, Jr., Michael Wayne Young
49 * Permission to use, copy, modify and distribute this software and
50 * its documentation is hereby granted, provided that both the copyright
51 * notice and this permission notice appear in all copies of the
52 * software, derivative works or modified versions, and any portions
53 * thereof, and that both notices appear in supporting documentation.
55 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
56 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
57 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
59 * Carnegie Mellon requests users of this software to return to
61 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
62 * School of Computer Science
63 * Carnegie Mellon University
64 * Pittsburgh PA 15213-3890
66 * any improvements or extensions that they make and grant Carnegie the
67 * rights to redistribute these changes.
70 * Resident memory management module. The module manipulates 'VM pages'.
71 * A VM page is the core building block for memory management.
74 #include <sys/param.h>
75 #include <sys/systm.h>
76 #include <sys/malloc.h>
78 #include <sys/vmmeter.h>
79 #include <sys/vnode.h>
82 #include <vm/vm_param.h>
84 #include <vm/vm_kern.h>
86 #include <vm/vm_map.h>
87 #include <vm/vm_object.h>
88 #include <vm/vm_page.h>
89 #include <vm/vm_pageout.h>
90 #include <vm/vm_pager.h>
91 #include <vm/vm_extern.h>
92 #include <vm/swap_pager.h>
94 #include <machine/md_var.h>
96 #include <vm/vm_page2.h>
97 #include <sys/mplock2.h>
99 static void vm_page_queue_init(void);
100 static void vm_page_free_wakeup(void);
101 static vm_page_t vm_page_select_cache(vm_object_t, vm_pindex_t);
102 static vm_page_t _vm_page_list_find2(int basequeue, int index);
104 struct vpgqueues vm_page_queues[PQ_COUNT]; /* Array of tailq lists */
106 #define ASSERT_IN_CRIT_SECTION() KKASSERT(crit_test(curthread));
108 RB_GENERATE2(vm_page_rb_tree, vm_page, rb_entry, rb_vm_page_compare,
109 vm_pindex_t, pindex);
112 vm_page_queue_init(void)
116 for (i = 0; i < PQ_L2_SIZE; i++)
117 vm_page_queues[PQ_FREE+i].cnt = &vmstats.v_free_count;
118 for (i = 0; i < PQ_L2_SIZE; i++)
119 vm_page_queues[PQ_CACHE+i].cnt = &vmstats.v_cache_count;
121 vm_page_queues[PQ_INACTIVE].cnt = &vmstats.v_inactive_count;
122 vm_page_queues[PQ_ACTIVE].cnt = &vmstats.v_active_count;
123 vm_page_queues[PQ_HOLD].cnt = &vmstats.v_active_count;
124 /* PQ_NONE has no queue */
126 for (i = 0; i < PQ_COUNT; i++)
127 TAILQ_INIT(&vm_page_queues[i].pl);
131 * note: place in initialized data section? Is this necessary?
134 int vm_page_array_size = 0;
135 int vm_page_zero_count = 0;
136 vm_page_t vm_page_array = 0;
141 * Sets the page size, perhaps based upon the memory size.
142 * Must be called before any use of page-size dependent functions.
145 vm_set_page_size(void)
147 if (vmstats.v_page_size == 0)
148 vmstats.v_page_size = PAGE_SIZE;
149 if (((vmstats.v_page_size - 1) & vmstats.v_page_size) != 0)
150 panic("vm_set_page_size: page size not a power of two");
156 * Add a new page to the freelist for use by the system. New pages
157 * are added to both the head and tail of the associated free page
158 * queue in a bottom-up fashion, so both zero'd and non-zero'd page
159 * requests pull 'recent' adds (higher physical addresses) first.
161 * Must be called in a critical section.
164 vm_add_new_page(vm_paddr_t pa)
166 struct vpgqueues *vpq;
169 ++vmstats.v_page_count;
170 ++vmstats.v_free_count;
171 m = PHYS_TO_VM_PAGE(pa);
174 m->pc = (pa >> PAGE_SHIFT) & PQ_L2_MASK;
175 m->queue = m->pc + PQ_FREE;
176 KKASSERT(m->dirty == 0);
178 vpq = &vm_page_queues[m->queue];
180 TAILQ_INSERT_TAIL(&vpq->pl, m, pageq);
182 TAILQ_INSERT_HEAD(&vpq->pl, m, pageq);
183 vpq->flipflop = 1 - vpq->flipflop;
185 vm_page_queues[m->queue].lcnt++;
192 * Initializes the resident memory module.
194 * Allocates memory for the page cells, and for the object/offset-to-page
195 * hash table headers. Each page cell is initialized and placed on the
198 * starta/enda represents the range of physical memory addresses available
199 * for use (skipping memory already used by the kernel), subject to
200 * phys_avail[]. Note that phys_avail[] has already mapped out memory
201 * already in use by the kernel.
204 vm_page_startup(vm_offset_t vaddr)
208 vm_paddr_t page_range;
215 vm_paddr_t biggestone, biggestsize;
222 vaddr = round_page(vaddr);
224 for (i = 0; phys_avail[i + 1]; i += 2) {
225 phys_avail[i] = round_page64(phys_avail[i]);
226 phys_avail[i + 1] = trunc_page64(phys_avail[i + 1]);
229 for (i = 0; phys_avail[i + 1]; i += 2) {
230 vm_paddr_t size = phys_avail[i + 1] - phys_avail[i];
232 if (size > biggestsize) {
240 end = phys_avail[biggestone+1];
241 end = trunc_page(end);
244 * Initialize the queue headers for the free queue, the active queue
245 * and the inactive queue.
248 vm_page_queue_init();
250 /* VKERNELs don't support minidumps and as such don't need vm_page_dump */
251 #if !defined(_KERNEL_VIRTUAL)
253 * Allocate a bitmap to indicate that a random physical page
254 * needs to be included in a minidump.
256 * The amd64 port needs this to indicate which direct map pages
257 * need to be dumped, via calls to dump_add_page()/dump_drop_page().
259 * However, i386 still needs this workspace internally within the
260 * minidump code. In theory, they are not needed on i386, but are
261 * included should the sf_buf code decide to use them.
263 page_range = phys_avail[(nblocks - 1) * 2 + 1] / PAGE_SIZE;
264 vm_page_dump_size = round_page(roundup2(page_range, NBBY) / NBBY);
265 end -= vm_page_dump_size;
266 vm_page_dump = (void *)pmap_map(&vaddr, end, end + vm_page_dump_size,
267 VM_PROT_READ | VM_PROT_WRITE);
268 bzero((void *)vm_page_dump, vm_page_dump_size);
272 * Compute the number of pages of memory that will be available for
273 * use (taking into account the overhead of a page structure per
276 first_page = phys_avail[0] / PAGE_SIZE;
277 page_range = phys_avail[(nblocks - 1) * 2 + 1] / PAGE_SIZE - first_page;
278 npages = (total - (page_range * sizeof(struct vm_page))) / PAGE_SIZE;
281 * Initialize the mem entry structures now, and put them in the free
284 new_end = trunc_page(end - page_range * sizeof(struct vm_page));
285 mapped = pmap_map(&vaddr, new_end, end,
286 VM_PROT_READ | VM_PROT_WRITE);
287 vm_page_array = (vm_page_t)mapped;
289 #if defined(__x86_64__) && !defined(_KERNEL_VIRTUAL)
291 * since pmap_map on amd64 returns stuff out of a direct-map region,
292 * we have to manually add these pages to the minidump tracking so
293 * that they can be dumped, including the vm_page_array.
295 for (pa = new_end; pa < phys_avail[biggestone + 1]; pa += PAGE_SIZE)
300 * Clear all of the page structures
302 bzero((caddr_t) vm_page_array, page_range * sizeof(struct vm_page));
303 vm_page_array_size = page_range;
306 * Construct the free queue(s) in ascending order (by physical
307 * address) so that the first 16MB of physical memory is allocated
308 * last rather than first. On large-memory machines, this avoids
309 * the exhaustion of low physical memory before isa_dmainit has run.
311 vmstats.v_page_count = 0;
312 vmstats.v_free_count = 0;
313 for (i = 0; phys_avail[i + 1] && npages > 0; i += 2) {
318 last_pa = phys_avail[i + 1];
319 while (pa < last_pa && npages-- > 0) {
328 * Scan comparison function for Red-Black tree scans. An inclusive
329 * (start,end) is expected. Other fields are not used.
332 rb_vm_page_scancmp(struct vm_page *p, void *data)
334 struct rb_vm_page_scan_info *info = data;
336 if (p->pindex < info->start_pindex)
338 if (p->pindex > info->end_pindex)
344 rb_vm_page_compare(struct vm_page *p1, struct vm_page *p2)
346 if (p1->pindex < p2->pindex)
348 if (p1->pindex > p2->pindex)
354 * The opposite of vm_page_hold(). A page can be freed while being held,
355 * which places it on the PQ_HOLD queue. We must call vm_page_free_toq()
356 * in this case to actually free it once the hold count drops to 0.
358 * This routine must be called at splvm().
361 vm_page_unhold(vm_page_t mem)
364 KASSERT(mem->hold_count >= 0, ("vm_page_unhold: hold count < 0!!!"));
365 if (mem->hold_count == 0 && mem->queue == PQ_HOLD) {
367 vm_page_free_toq(mem);
372 * Inserts the given mem entry into the object and object list.
374 * The pagetables are not updated but will presumably fault the page
375 * in if necessary, or if a kernel page the caller will at some point
376 * enter the page into the kernel's pmap. We are not allowed to block
377 * here so we *can't* do this anyway.
379 * This routine may not block.
380 * This routine must be called with a critical section held.
383 vm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex)
385 ASSERT_IN_CRIT_SECTION();
386 if (m->object != NULL)
387 panic("vm_page_insert: already inserted");
390 * Record the object/offset pair in this page
396 * Insert it into the object.
398 ASSERT_MP_LOCK_HELD(curthread);
399 vm_page_rb_tree_RB_INSERT(&object->rb_memq, m);
400 object->generation++;
403 * show that the object has one more resident page.
405 object->resident_page_count++;
408 * Since we are inserting a new and possibly dirty page,
409 * update the object's OBJ_WRITEABLE and OBJ_MIGHTBEDIRTY flags.
411 if ((m->valid & m->dirty) || (m->flags & PG_WRITEABLE))
412 vm_object_set_writeable_dirty(object);
415 * Checks for a swap assignment and sets PG_SWAPPED if appropriate.
417 swap_pager_page_inserted(m);
421 * Removes the given vm_page_t from the global (object,index) hash table
422 * and from the object's memq.
424 * The underlying pmap entry (if any) is NOT removed here.
425 * This routine may not block.
427 * The page must be BUSY and will remain BUSY on return.
428 * No other requirements.
430 * NOTE: FreeBSD side effect was to unbusy the page on return. We leave
434 vm_page_remove(vm_page_t m)
439 lwkt_gettoken(&vm_token);
440 if (m->object == NULL) {
441 lwkt_reltoken(&vm_token);
446 if ((m->flags & PG_BUSY) == 0)
447 panic("vm_page_remove: page not busy");
452 * Remove the page from the object and update the object.
454 ASSERT_MP_LOCK_HELD(curthread);
455 vm_page_rb_tree_RB_REMOVE(&object->rb_memq, m);
456 object->resident_page_count--;
457 object->generation++;
460 lwkt_reltoken(&vm_token);
465 * Locate and return the page at (object, pindex), or NULL if the
466 * page could not be found.
468 * This routine will operate properly without spl protection, but
469 * the returned page could be in flux if it is busy. Because an
470 * interrupt can race a caller's busy check (unbusying and freeing the
471 * page we return before the caller is able to check the busy bit),
472 * the caller should generally call this routine with a critical
475 * Callers may call this routine without spl protection if they know
476 * 'for sure' that the page will not be ripped out from under them
480 vm_page_lookup(vm_object_t object, vm_pindex_t pindex)
485 * Search the hash table for this object/offset pair
487 ASSERT_MP_LOCK_HELD(curthread);
489 lwkt_gettoken(&vm_token);
490 m = vm_page_rb_tree_RB_LOOKUP(&object->rb_memq, pindex);
491 lwkt_reltoken(&vm_token);
493 KKASSERT(m == NULL || (m->object == object && m->pindex == pindex));
500 * Move the given memory entry from its current object to the specified
501 * target object/offset.
503 * The object must be locked.
504 * This routine may not block.
506 * Note: This routine will raise itself to splvm(), the caller need not.
508 * Note: Swap associated with the page must be invalidated by the move. We
509 * have to do this for several reasons: (1) we aren't freeing the
510 * page, (2) we are dirtying the page, (3) the VM system is probably
511 * moving the page from object A to B, and will then later move
512 * the backing store from A to B and we can't have a conflict.
514 * Note: We *always* dirty the page. It is necessary both for the
515 * fact that we moved it, and because we may be invalidating
516 * swap. If the page is on the cache, we have to deactivate it
517 * or vm_page_dirty() will panic. Dirty pages are not allowed
521 vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex)
524 lwkt_gettoken(&vm_token);
526 vm_page_insert(m, new_object, new_pindex);
527 if (m->queue - m->pc == PQ_CACHE)
528 vm_page_deactivate(m);
531 lwkt_reltoken(&vm_token);
536 * vm_page_unqueue() without any wakeup. This routine is used when a page
537 * is being moved between queues or otherwise is to remain BUSYied by the
540 * This routine must be called at splhigh().
541 * This routine may not block.
544 vm_page_unqueue_nowakeup(vm_page_t m)
546 int queue = m->queue;
547 struct vpgqueues *pq;
549 if (queue != PQ_NONE) {
550 pq = &vm_page_queues[queue];
552 TAILQ_REMOVE(&pq->pl, m, pageq);
559 * vm_page_unqueue() - Remove a page from its queue, wakeup the pagedemon
562 * This routine must be called at splhigh().
563 * This routine may not block.
566 vm_page_unqueue(vm_page_t m)
568 int queue = m->queue;
569 struct vpgqueues *pq;
571 if (queue != PQ_NONE) {
573 pq = &vm_page_queues[queue];
574 TAILQ_REMOVE(&pq->pl, m, pageq);
577 if ((queue - m->pc) == PQ_CACHE || (queue - m->pc) == PQ_FREE)
583 * vm_page_list_find()
585 * Find a page on the specified queue with color optimization.
587 * The page coloring optimization attempts to locate a page that does
588 * not overload other nearby pages in the object in the cpu's L1 or L2
589 * caches. We need this optimization because cpu caches tend to be
590 * physical caches, while object spaces tend to be virtual.
592 * This routine must be called at splvm().
593 * This routine may not block.
595 * Note that this routine is carefully inlined. A non-inlined version
596 * is available for outside callers but the only critical path is
597 * from within this source file.
601 _vm_page_list_find(int basequeue, int index, boolean_t prefer_zero)
606 m = TAILQ_LAST(&vm_page_queues[basequeue+index].pl, pglist);
608 m = TAILQ_FIRST(&vm_page_queues[basequeue+index].pl);
610 m = _vm_page_list_find2(basequeue, index);
615 _vm_page_list_find2(int basequeue, int index)
619 struct vpgqueues *pq;
621 pq = &vm_page_queues[basequeue];
624 * Note that for the first loop, index+i and index-i wind up at the
625 * same place. Even though this is not totally optimal, we've already
626 * blown it by missing the cache case so we do not care.
629 for(i = PQ_L2_SIZE / 2; i > 0; --i) {
630 if ((m = TAILQ_FIRST(&pq[(index + i) & PQ_L2_MASK].pl)) != NULL)
633 if ((m = TAILQ_FIRST(&pq[(index - i) & PQ_L2_MASK].pl)) != NULL)
640 vm_page_list_find(int basequeue, int index, boolean_t prefer_zero)
642 return(_vm_page_list_find(basequeue, index, prefer_zero));
646 * Find a page on the cache queue with color optimization. As pages
647 * might be found, but not applicable, they are deactivated. This
648 * keeps us from using potentially busy cached pages.
650 * This routine must be called with a critical section held.
651 * This routine may not block.
654 vm_page_select_cache(vm_object_t object, vm_pindex_t pindex)
659 m = _vm_page_list_find(
661 (pindex + object->pg_color) & PQ_L2_MASK,
664 if (m && ((m->flags & (PG_BUSY|PG_UNMANAGED)) || m->busy ||
665 m->hold_count || m->wire_count)) {
666 vm_page_deactivate(m);
675 * Find a free or zero page, with specified preference. We attempt to
676 * inline the nominal case and fall back to _vm_page_select_free()
679 * This routine must be called with a critical section held.
680 * This routine may not block.
682 static __inline vm_page_t
683 vm_page_select_free(vm_object_t object, vm_pindex_t pindex, boolean_t prefer_zero)
687 m = _vm_page_list_find(
689 (pindex + object->pg_color) & PQ_L2_MASK,
698 * Allocate and return a memory cell associated with this VM object/offset
703 * VM_ALLOC_NORMAL allow use of cache pages, nominal free drain
704 * VM_ALLOC_QUICK like normal but cannot use cache
705 * VM_ALLOC_SYSTEM greater free drain
706 * VM_ALLOC_INTERRUPT allow free list to be completely drained
707 * VM_ALLOC_ZERO advisory request for pre-zero'd page
709 * The object must be locked.
710 * This routine may not block.
711 * The returned page will be marked PG_BUSY
713 * Additional special handling is required when called from an interrupt
714 * (VM_ALLOC_INTERRUPT). We are not allowed to mess with the page cache
718 vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int page_req)
722 KKASSERT(object != NULL);
723 KASSERT(!vm_page_lookup(object, pindex),
724 ("vm_page_alloc: page already allocated"));
726 (VM_ALLOC_NORMAL|VM_ALLOC_QUICK|
727 VM_ALLOC_INTERRUPT|VM_ALLOC_SYSTEM));
730 * Certain system threads (pageout daemon, buf_daemon's) are
731 * allowed to eat deeper into the free page list.
733 if (curthread->td_flags & TDF_SYSTHREAD)
734 page_req |= VM_ALLOC_SYSTEM;
737 lwkt_gettoken(&vm_token);
739 if (vmstats.v_free_count > vmstats.v_free_reserved ||
740 ((page_req & VM_ALLOC_INTERRUPT) && vmstats.v_free_count > 0) ||
741 ((page_req & VM_ALLOC_SYSTEM) && vmstats.v_cache_count == 0 &&
742 vmstats.v_free_count > vmstats.v_interrupt_free_min)
745 * The free queue has sufficient free pages to take one out.
747 if (page_req & VM_ALLOC_ZERO)
748 m = vm_page_select_free(object, pindex, TRUE);
750 m = vm_page_select_free(object, pindex, FALSE);
751 } else if (page_req & VM_ALLOC_NORMAL) {
753 * Allocatable from the cache (non-interrupt only). On
754 * success, we must free the page and try again, thus
755 * ensuring that vmstats.v_*_free_min counters are replenished.
758 if (curthread->td_preempted) {
759 kprintf("vm_page_alloc(): warning, attempt to allocate"
760 " cache page from preempting interrupt\n");
763 m = vm_page_select_cache(object, pindex);
766 m = vm_page_select_cache(object, pindex);
769 * On success move the page into the free queue and loop.
772 KASSERT(m->dirty == 0,
773 ("Found dirty cache page %p", m));
775 vm_page_protect(m, VM_PROT_NONE);
781 * On failure return NULL
783 lwkt_reltoken(&vm_token);
785 #if defined(DIAGNOSTIC)
786 if (vmstats.v_cache_count > 0)
787 kprintf("vm_page_alloc(NORMAL): missing pages on cache queue: %d\n", vmstats.v_cache_count);
789 vm_pageout_deficit++;
794 * No pages available, wakeup the pageout daemon and give up.
796 lwkt_reltoken(&vm_token);
798 vm_pageout_deficit++;
804 * Good page found. The page has not yet been busied. We are in
805 * a critical section.
807 KASSERT(m != NULL, ("vm_page_alloc(): missing page on free queue\n"));
808 KASSERT(m->dirty == 0,
809 ("vm_page_alloc: free/cache page %p was dirty", m));
812 * Remove from free queue
814 vm_page_unqueue_nowakeup(m);
817 * Initialize structure. Only the PG_ZERO flag is inherited. Set
820 if (m->flags & PG_ZERO) {
821 vm_page_zero_count--;
822 m->flags = PG_ZERO | PG_BUSY;
833 * vm_page_insert() is safe prior to the crit_exit(). Note also that
834 * inserting a page here does not insert it into the pmap (which
835 * could cause us to block allocating memory). We cannot block
838 vm_page_insert(m, object, pindex);
841 * Don't wakeup too often - wakeup the pageout daemon when
842 * we would be nearly out of memory.
846 lwkt_reltoken(&vm_token);
850 * A PG_BUSY page is returned.
856 * Wait for sufficient free memory for nominal heavy memory use kernel
860 vm_wait_nominal(void)
862 while (vm_page_count_min(0))
867 * Test if vm_wait_nominal() would block.
870 vm_test_nominal(void)
872 if (vm_page_count_min(0))
878 * Block until free pages are available for allocation, called in various
879 * places before memory allocations.
885 lwkt_gettoken(&vm_token);
886 if (curthread == pagethread) {
887 vm_pageout_pages_needed = 1;
888 tsleep(&vm_pageout_pages_needed, 0, "VMWait", timo);
890 if (vm_pages_needed == 0) {
892 wakeup(&vm_pages_needed);
894 tsleep(&vmstats.v_free_count, 0, "vmwait", timo);
896 lwkt_reltoken(&vm_token);
901 * Block until free pages are available for allocation
903 * Called only in vm_fault so that processes page faulting can be
910 lwkt_gettoken(&vm_token);
911 if (vm_pages_needed == 0) {
913 wakeup(&vm_pages_needed);
915 tsleep(&vmstats.v_free_count, 0, "pfault", 0);
916 lwkt_reltoken(&vm_token);
921 * Put the specified page on the active list (if appropriate). Ensure
922 * that act_count is at least ACT_INIT but do not otherwise mess with it.
924 * The page queues must be locked.
925 * This routine may not block.
928 vm_page_activate(vm_page_t m)
931 lwkt_gettoken(&vm_token);
932 if (m->queue != PQ_ACTIVE) {
933 if ((m->queue - m->pc) == PQ_CACHE)
934 mycpu->gd_cnt.v_reactivated++;
938 if (m->wire_count == 0 && (m->flags & PG_UNMANAGED) == 0) {
939 m->queue = PQ_ACTIVE;
940 vm_page_queues[PQ_ACTIVE].lcnt++;
941 TAILQ_INSERT_TAIL(&vm_page_queues[PQ_ACTIVE].pl,
943 if (m->act_count < ACT_INIT)
944 m->act_count = ACT_INIT;
945 vmstats.v_active_count++;
948 if (m->act_count < ACT_INIT)
949 m->act_count = ACT_INIT;
951 lwkt_reltoken(&vm_token);
956 * Helper routine for vm_page_free_toq() and vm_page_cache(). This
957 * routine is called when a page has been added to the cache or free
960 * This routine may not block.
961 * This routine must be called at splvm()
964 vm_page_free_wakeup(void)
967 * if pageout daemon needs pages, then tell it that there are
970 if (vm_pageout_pages_needed &&
971 vmstats.v_cache_count + vmstats.v_free_count >=
972 vmstats.v_pageout_free_min
974 wakeup(&vm_pageout_pages_needed);
975 vm_pageout_pages_needed = 0;
979 * wakeup processes that are waiting on memory if we hit a
980 * high water mark. And wakeup scheduler process if we have
981 * lots of memory. this process will swapin processes.
983 if (vm_pages_needed && !vm_page_count_min(0)) {
985 wakeup(&vmstats.v_free_count);
992 * Returns the given page to the PQ_FREE list, disassociating it with
995 * The vm_page must be PG_BUSY on entry. PG_BUSY will be released on
996 * return (the page will have been freed). No particular spl is required
999 * This routine may not block.
1002 vm_page_free_toq(vm_page_t m)
1004 struct vpgqueues *pq;
1007 lwkt_gettoken(&vm_token);
1008 mycpu->gd_cnt.v_tfree++;
1010 KKASSERT((m->flags & PG_MAPPED) == 0);
1012 if (m->busy || ((m->queue - m->pc) == PQ_FREE)) {
1014 "vm_page_free: pindex(%lu), busy(%d), PG_BUSY(%d), hold(%d)\n",
1015 (u_long)m->pindex, m->busy, (m->flags & PG_BUSY) ? 1 : 0,
1017 if ((m->queue - m->pc) == PQ_FREE)
1018 panic("vm_page_free: freeing free page");
1020 panic("vm_page_free: freeing busy page");
1024 * unqueue, then remove page. Note that we cannot destroy
1025 * the page here because we do not want to call the pager's
1026 * callback routine until after we've put the page on the
1027 * appropriate free queue.
1029 vm_page_unqueue_nowakeup(m);
1033 * No further management of fictitious pages occurs beyond object
1034 * and queue removal.
1036 if ((m->flags & PG_FICTITIOUS) != 0) {
1038 lwkt_reltoken(&vm_token);
1046 if (m->wire_count != 0) {
1047 if (m->wire_count > 1) {
1049 "vm_page_free: invalid wire count (%d), pindex: 0x%lx",
1050 m->wire_count, (long)m->pindex);
1052 panic("vm_page_free: freeing wired page");
1056 * Clear the UNMANAGED flag when freeing an unmanaged page.
1058 if (m->flags & PG_UNMANAGED) {
1059 m->flags &= ~PG_UNMANAGED;
1062 if (m->hold_count != 0) {
1063 m->flags &= ~PG_ZERO;
1066 m->queue = PQ_FREE + m->pc;
1068 pq = &vm_page_queues[m->queue];
1073 * Put zero'd pages on the end ( where we look for zero'd pages
1074 * first ) and non-zerod pages at the head.
1076 if (m->flags & PG_ZERO) {
1077 TAILQ_INSERT_TAIL(&pq->pl, m, pageq);
1078 ++vm_page_zero_count;
1080 TAILQ_INSERT_HEAD(&pq->pl, m, pageq);
1083 vm_page_free_wakeup();
1084 lwkt_reltoken(&vm_token);
1089 * vm_page_free_fromq_fast()
1091 * Remove a non-zero page from one of the free queues; the page is removed for
1092 * zeroing, so do not issue a wakeup.
1097 vm_page_free_fromq_fast(void)
1104 lwkt_gettoken(&vm_token);
1105 for (i = 0; i < PQ_L2_SIZE; ++i) {
1106 m = vm_page_list_find(PQ_FREE, qi, FALSE);
1107 qi = (qi + PQ_PRIME2) & PQ_L2_MASK;
1108 if (m && (m->flags & PG_ZERO) == 0) {
1109 vm_page_unqueue_nowakeup(m);
1115 lwkt_reltoken(&vm_token);
1121 * vm_page_unmanage()
1123 * Prevent PV management from being done on the page. The page is
1124 * removed from the paging queues as if it were wired, and as a
1125 * consequence of no longer being managed the pageout daemon will not
1126 * touch it (since there is no way to locate the pte mappings for the
1127 * page). madvise() calls that mess with the pmap will also no longer
1128 * operate on the page.
1130 * Beyond that the page is still reasonably 'normal'. Freeing the page
1131 * will clear the flag.
1133 * This routine is used by OBJT_PHYS objects - objects using unswappable
1134 * physical memory as backing store rather then swap-backed memory and
1135 * will eventually be extended to support 4MB unmanaged physical
1138 * Must be called with a critical section held.
1141 vm_page_unmanage(vm_page_t m)
1143 ASSERT_IN_CRIT_SECTION();
1144 if ((m->flags & PG_UNMANAGED) == 0) {
1145 if (m->wire_count == 0)
1148 vm_page_flag_set(m, PG_UNMANAGED);
1152 * Mark this page as wired down by yet another map, removing it from
1153 * paging queues as necessary.
1155 * The page queues must be locked.
1156 * This routine may not block.
1159 vm_page_wire(vm_page_t m)
1162 * Only bump the wire statistics if the page is not already wired,
1163 * and only unqueue the page if it is on some queue (if it is unmanaged
1164 * it is already off the queues). Don't do anything with fictitious
1165 * pages because they are always wired.
1168 lwkt_gettoken(&vm_token);
1169 if ((m->flags & PG_FICTITIOUS) == 0) {
1170 if (m->wire_count == 0) {
1171 if ((m->flags & PG_UNMANAGED) == 0)
1173 vmstats.v_wire_count++;
1176 KASSERT(m->wire_count != 0,
1177 ("vm_page_wire: wire_count overflow m=%p", m));
1179 lwkt_reltoken(&vm_token);
1184 * Release one wiring of this page, potentially enabling it to be paged again.
1186 * Many pages placed on the inactive queue should actually go
1187 * into the cache, but it is difficult to figure out which. What
1188 * we do instead, if the inactive target is well met, is to put
1189 * clean pages at the head of the inactive queue instead of the tail.
1190 * This will cause them to be moved to the cache more quickly and
1191 * if not actively re-referenced, freed more quickly. If we just
1192 * stick these pages at the end of the inactive queue, heavy filesystem
1193 * meta-data accesses can cause an unnecessary paging load on memory bound
1194 * processes. This optimization causes one-time-use metadata to be
1195 * reused more quickly.
1197 * BUT, if we are in a low-memory situation we have no choice but to
1198 * put clean pages on the cache queue.
1200 * A number of routines use vm_page_unwire() to guarantee that the page
1201 * will go into either the inactive or active queues, and will NEVER
1202 * be placed in the cache - for example, just after dirtying a page.
1203 * dirty pages in the cache are not allowed.
1205 * The page queues must be locked.
1206 * This routine may not block.
1209 vm_page_unwire(vm_page_t m, int activate)
1212 lwkt_gettoken(&vm_token);
1213 if (m->flags & PG_FICTITIOUS) {
1215 } else if (m->wire_count <= 0) {
1216 panic("vm_page_unwire: invalid wire count: %d", m->wire_count);
1218 if (--m->wire_count == 0) {
1219 --vmstats.v_wire_count;
1220 if (m->flags & PG_UNMANAGED) {
1222 } else if (activate) {
1224 &vm_page_queues[PQ_ACTIVE].pl, m, pageq);
1225 m->queue = PQ_ACTIVE;
1226 vm_page_queues[PQ_ACTIVE].lcnt++;
1227 vmstats.v_active_count++;
1229 vm_page_flag_clear(m, PG_WINATCFLS);
1231 &vm_page_queues[PQ_INACTIVE].pl, m, pageq);
1232 m->queue = PQ_INACTIVE;
1233 vm_page_queues[PQ_INACTIVE].lcnt++;
1234 vmstats.v_inactive_count++;
1235 ++vm_swapcache_inactive_heuristic;
1239 lwkt_reltoken(&vm_token);
1245 * Move the specified page to the inactive queue. If the page has
1246 * any associated swap, the swap is deallocated.
1248 * Normally athead is 0 resulting in LRU operation. athead is set
1249 * to 1 if we want this page to be 'as if it were placed in the cache',
1250 * except without unmapping it from the process address space.
1252 * This routine may not block.
1254 static __inline void
1255 _vm_page_deactivate(vm_page_t m, int athead)
1258 * Ignore if already inactive.
1260 if (m->queue == PQ_INACTIVE)
1263 if (m->wire_count == 0 && (m->flags & PG_UNMANAGED) == 0) {
1264 if ((m->queue - m->pc) == PQ_CACHE)
1265 mycpu->gd_cnt.v_reactivated++;
1266 vm_page_flag_clear(m, PG_WINATCFLS);
1269 TAILQ_INSERT_HEAD(&vm_page_queues[PQ_INACTIVE].pl,
1272 TAILQ_INSERT_TAIL(&vm_page_queues[PQ_INACTIVE].pl,
1274 ++vm_swapcache_inactive_heuristic;
1276 m->queue = PQ_INACTIVE;
1277 vm_page_queues[PQ_INACTIVE].lcnt++;
1278 vmstats.v_inactive_count++;
1283 vm_page_deactivate(vm_page_t m)
1286 lwkt_gettoken(&vm_token);
1287 _vm_page_deactivate(m, 0);
1288 lwkt_reltoken(&vm_token);
1293 * vm_page_try_to_cache:
1295 * Returns 0 on failure, 1 on success
1298 vm_page_try_to_cache(vm_page_t m)
1301 lwkt_gettoken(&vm_token);
1302 if (m->dirty || m->hold_count || m->busy || m->wire_count ||
1303 (m->flags & (PG_BUSY|PG_UNMANAGED))) {
1304 lwkt_reltoken(&vm_token);
1308 vm_page_test_dirty(m);
1310 lwkt_reltoken(&vm_token);
1315 lwkt_reltoken(&vm_token);
1321 * Attempt to free the page. If we cannot free it, we do nothing.
1322 * 1 is returned on success, 0 on failure.
1325 vm_page_try_to_free(vm_page_t m)
1328 lwkt_gettoken(&vm_token);
1329 if (m->dirty || m->hold_count || m->busy || m->wire_count ||
1330 (m->flags & (PG_BUSY|PG_UNMANAGED))) {
1331 lwkt_reltoken(&vm_token);
1335 vm_page_test_dirty(m);
1337 lwkt_reltoken(&vm_token);
1342 vm_page_protect(m, VM_PROT_NONE);
1344 lwkt_reltoken(&vm_token);
1352 * Put the specified page onto the page cache queue (if appropriate).
1354 * This routine may not block.
1357 vm_page_cache(vm_page_t m)
1359 ASSERT_IN_CRIT_SECTION();
1361 if ((m->flags & (PG_BUSY|PG_UNMANAGED)) || m->busy ||
1362 m->wire_count || m->hold_count) {
1363 kprintf("vm_page_cache: attempting to cache busy/held page\n");
1368 * Already in the cache (and thus not mapped)
1370 if ((m->queue - m->pc) == PQ_CACHE) {
1371 KKASSERT((m->flags & PG_MAPPED) == 0);
1376 * Caller is required to test m->dirty, but note that the act of
1377 * removing the page from its maps can cause it to become dirty
1378 * on an SMP system due to another cpu running in usermode.
1381 panic("vm_page_cache: caching a dirty page, pindex: %ld",
1386 * Remove all pmaps and indicate that the page is not
1387 * writeable or mapped. Our vm_page_protect() call may
1388 * have blocked (especially w/ VM_PROT_NONE), so recheck
1392 vm_page_protect(m, VM_PROT_NONE);
1394 if ((m->flags & (PG_BUSY|PG_UNMANAGED|PG_MAPPED)) || m->busy ||
1395 m->wire_count || m->hold_count) {
1397 } else if (m->dirty) {
1398 vm_page_deactivate(m);
1400 vm_page_unqueue_nowakeup(m);
1401 m->queue = PQ_CACHE + m->pc;
1402 vm_page_queues[m->queue].lcnt++;
1403 TAILQ_INSERT_TAIL(&vm_page_queues[m->queue].pl, m, pageq);
1404 vmstats.v_cache_count++;
1405 vm_page_free_wakeup();
1410 * vm_page_dontneed()
1412 * Cache, deactivate, or do nothing as appropriate. This routine
1413 * is typically used by madvise() MADV_DONTNEED.
1415 * Generally speaking we want to move the page into the cache so
1416 * it gets reused quickly. However, this can result in a silly syndrome
1417 * due to the page recycling too quickly. Small objects will not be
1418 * fully cached. On the otherhand, if we move the page to the inactive
1419 * queue we wind up with a problem whereby very large objects
1420 * unnecessarily blow away our inactive and cache queues.
1422 * The solution is to move the pages based on a fixed weighting. We
1423 * either leave them alone, deactivate them, or move them to the cache,
1424 * where moving them to the cache has the highest weighting.
1425 * By forcing some pages into other queues we eventually force the
1426 * system to balance the queues, potentially recovering other unrelated
1427 * space from active. The idea is to not force this to happen too
1431 vm_page_dontneed(vm_page_t m)
1433 static int dnweight;
1440 * occassionally leave the page alone
1443 lwkt_gettoken(&vm_token);
1444 if ((dnw & 0x01F0) == 0 ||
1445 m->queue == PQ_INACTIVE ||
1446 m->queue - m->pc == PQ_CACHE
1448 if (m->act_count >= ACT_INIT)
1450 lwkt_reltoken(&vm_token);
1456 vm_page_test_dirty(m);
1458 if (m->dirty || (dnw & 0x0070) == 0) {
1460 * Deactivate the page 3 times out of 32.
1465 * Cache the page 28 times out of every 32. Note that
1466 * the page is deactivated instead of cached, but placed
1467 * at the head of the queue instead of the tail.
1471 _vm_page_deactivate(m, head);
1472 lwkt_reltoken(&vm_token);
1477 * Grab a page, blocking if it is busy and allocating a page if necessary.
1478 * A busy page is returned or NULL.
1480 * If VM_ALLOC_RETRY is specified VM_ALLOC_NORMAL must also be specified.
1481 * If VM_ALLOC_RETRY is not specified
1483 * This routine may block, but if VM_ALLOC_RETRY is not set then NULL is
1484 * always returned if we had blocked.
1485 * This routine will never return NULL if VM_ALLOC_RETRY is set.
1486 * This routine may not be called from an interrupt.
1487 * The returned page may not be entirely valid.
1489 * This routine may be called from mainline code without spl protection and
1490 * be guarenteed a busied page associated with the object at the specified
1494 vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags)
1499 KKASSERT(allocflags &
1500 (VM_ALLOC_NORMAL|VM_ALLOC_INTERRUPT|VM_ALLOC_SYSTEM));
1502 lwkt_gettoken(&vm_token);
1504 if ((m = vm_page_lookup(object, pindex)) != NULL) {
1505 if (m->busy || (m->flags & PG_BUSY)) {
1506 generation = object->generation;
1508 while ((object->generation == generation) &&
1509 (m->busy || (m->flags & PG_BUSY))) {
1510 vm_page_flag_set(m, PG_WANTED | PG_REFERENCED);
1511 tsleep(m, 0, "pgrbwt", 0);
1512 if ((allocflags & VM_ALLOC_RETRY) == 0) {
1523 m = vm_page_alloc(object, pindex, allocflags & ~VM_ALLOC_RETRY);
1526 if ((allocflags & VM_ALLOC_RETRY) == 0)
1531 lwkt_reltoken(&vm_token);
1537 * Mapping function for valid bits or for dirty bits in
1538 * a page. May not block.
1540 * Inputs are required to range within a page.
1543 vm_page_bits(int base, int size)
1549 base + size <= PAGE_SIZE,
1550 ("vm_page_bits: illegal base/size %d/%d", base, size)
1553 if (size == 0) /* handle degenerate case */
1556 first_bit = base >> DEV_BSHIFT;
1557 last_bit = (base + size - 1) >> DEV_BSHIFT;
1559 return ((2 << last_bit) - (1 << first_bit));
1563 * Sets portions of a page valid and clean. The arguments are expected
1564 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive
1565 * of any partial chunks touched by the range. The invalid portion of
1566 * such chunks will be zero'd.
1568 * NOTE: When truncating a buffer vnode_pager_setsize() will automatically
1569 * align base to DEV_BSIZE so as not to mark clean a partially
1570 * truncated device block. Otherwise the dirty page status might be
1573 * This routine may not block.
1575 * (base + size) must be less then or equal to PAGE_SIZE.
1578 _vm_page_zero_valid(vm_page_t m, int base, int size)
1583 if (size == 0) /* handle degenerate case */
1587 * If the base is not DEV_BSIZE aligned and the valid
1588 * bit is clear, we have to zero out a portion of the
1592 if ((frag = base & ~(DEV_BSIZE - 1)) != base &&
1593 (m->valid & (1 << (base >> DEV_BSHIFT))) == 0
1595 pmap_zero_page_area(
1603 * If the ending offset is not DEV_BSIZE aligned and the
1604 * valid bit is clear, we have to zero out a portion of
1608 endoff = base + size;
1610 if ((frag = endoff & ~(DEV_BSIZE - 1)) != endoff &&
1611 (m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0
1613 pmap_zero_page_area(
1616 DEV_BSIZE - (endoff & (DEV_BSIZE - 1))
1622 * Set valid, clear dirty bits. If validating the entire
1623 * page we can safely clear the pmap modify bit. We also
1624 * use this opportunity to clear the PG_NOSYNC flag. If a process
1625 * takes a write fault on a MAP_NOSYNC memory area the flag will
1628 * We set valid bits inclusive of any overlap, but we can only
1629 * clear dirty bits for DEV_BSIZE chunks that are fully within
1633 vm_page_set_valid(vm_page_t m, int base, int size)
1635 _vm_page_zero_valid(m, base, size);
1636 m->valid |= vm_page_bits(base, size);
1641 * Set valid bits and clear dirty bits.
1643 * NOTE: This function does not clear the pmap modified bit.
1644 * Also note that e.g. NFS may use a byte-granular base
1648 vm_page_set_validclean(vm_page_t m, int base, int size)
1652 _vm_page_zero_valid(m, base, size);
1653 pagebits = vm_page_bits(base, size);
1654 m->valid |= pagebits;
1655 m->dirty &= ~pagebits;
1656 if (base == 0 && size == PAGE_SIZE) {
1657 /*pmap_clear_modify(m);*/
1658 vm_page_flag_clear(m, PG_NOSYNC);
1663 * Set valid & dirty. Used by buwrite()
1666 vm_page_set_validdirty(vm_page_t m, int base, int size)
1670 pagebits = vm_page_bits(base, size);
1671 m->valid |= pagebits;
1672 m->dirty |= pagebits;
1674 vm_object_set_writeable_dirty(m->object);
1680 * NOTE: This function does not clear the pmap modified bit.
1681 * Also note that e.g. NFS may use a byte-granular base
1685 vm_page_clear_dirty(vm_page_t m, int base, int size)
1687 m->dirty &= ~vm_page_bits(base, size);
1688 if (base == 0 && size == PAGE_SIZE) {
1689 /*pmap_clear_modify(m);*/
1690 vm_page_flag_clear(m, PG_NOSYNC);
1695 * Make the page all-dirty.
1697 * Also make sure the related object and vnode reflect the fact that the
1698 * object may now contain a dirty page.
1701 vm_page_dirty(vm_page_t m)
1704 int pqtype = m->queue - m->pc;
1706 KASSERT(pqtype != PQ_CACHE && pqtype != PQ_FREE,
1707 ("vm_page_dirty: page in free/cache queue!"));
1708 if (m->dirty != VM_PAGE_BITS_ALL) {
1709 m->dirty = VM_PAGE_BITS_ALL;
1711 vm_object_set_writeable_dirty(m->object);
1716 * Invalidates DEV_BSIZE'd chunks within a page. Both the
1717 * valid and dirty bits for the effected areas are cleared.
1722 vm_page_set_invalid(vm_page_t m, int base, int size)
1726 bits = vm_page_bits(base, size);
1729 m->object->generation++;
1733 * The kernel assumes that the invalid portions of a page contain
1734 * garbage, but such pages can be mapped into memory by user code.
1735 * When this occurs, we must zero out the non-valid portions of the
1736 * page so user code sees what it expects.
1738 * Pages are most often semi-valid when the end of a file is mapped
1739 * into memory and the file's size is not page aligned.
1742 vm_page_zero_invalid(vm_page_t m, boolean_t setvalid)
1748 * Scan the valid bits looking for invalid sections that
1749 * must be zerod. Invalid sub-DEV_BSIZE'd areas ( where the
1750 * valid bit may be set ) have already been zerod by
1751 * vm_page_set_validclean().
1753 for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) {
1754 if (i == (PAGE_SIZE / DEV_BSIZE) ||
1755 (m->valid & (1 << i))
1758 pmap_zero_page_area(
1761 (i - b) << DEV_BSHIFT
1769 * setvalid is TRUE when we can safely set the zero'd areas
1770 * as being valid. We can do this if there are no cache consistency
1771 * issues. e.g. it is ok to do with UFS, but not ok to do with NFS.
1774 m->valid = VM_PAGE_BITS_ALL;
1778 * Is a (partial) page valid? Note that the case where size == 0
1779 * will return FALSE in the degenerate case where the page is entirely
1780 * invalid, and TRUE otherwise.
1785 vm_page_is_valid(vm_page_t m, int base, int size)
1787 int bits = vm_page_bits(base, size);
1789 if (m->valid && ((m->valid & bits) == bits))
1796 * update dirty bits from pmap/mmu. May not block.
1799 vm_page_test_dirty(vm_page_t m)
1801 if ((m->dirty != VM_PAGE_BITS_ALL) && pmap_is_modified(m)) {
1807 * Issue an event on a VM page. Corresponding action structures are
1808 * removed from the page's list and called.
1811 vm_page_event_internal(vm_page_t m, vm_page_event_t event)
1813 struct vm_page_action *scan, *next;
1815 LIST_FOREACH_MUTABLE(scan, &m->action_list, entry, next) {
1816 if (scan->event == event) {
1817 scan->event = VMEVENT_NONE;
1818 LIST_REMOVE(scan, entry);
1819 scan->func(m, scan);
1825 #include "opt_ddb.h"
1827 #include <sys/kernel.h>
1829 #include <ddb/ddb.h>
1831 DB_SHOW_COMMAND(page, vm_page_print_page_info)
1833 db_printf("vmstats.v_free_count: %d\n", vmstats.v_free_count);
1834 db_printf("vmstats.v_cache_count: %d\n", vmstats.v_cache_count);
1835 db_printf("vmstats.v_inactive_count: %d\n", vmstats.v_inactive_count);
1836 db_printf("vmstats.v_active_count: %d\n", vmstats.v_active_count);
1837 db_printf("vmstats.v_wire_count: %d\n", vmstats.v_wire_count);
1838 db_printf("vmstats.v_free_reserved: %d\n", vmstats.v_free_reserved);
1839 db_printf("vmstats.v_free_min: %d\n", vmstats.v_free_min);
1840 db_printf("vmstats.v_free_target: %d\n", vmstats.v_free_target);
1841 db_printf("vmstats.v_cache_min: %d\n", vmstats.v_cache_min);
1842 db_printf("vmstats.v_inactive_target: %d\n", vmstats.v_inactive_target);
1845 DB_SHOW_COMMAND(pageq, vm_page_print_pageq_info)
1848 db_printf("PQ_FREE:");
1849 for(i=0;i<PQ_L2_SIZE;i++) {
1850 db_printf(" %d", vm_page_queues[PQ_FREE + i].lcnt);
1854 db_printf("PQ_CACHE:");
1855 for(i=0;i<PQ_L2_SIZE;i++) {
1856 db_printf(" %d", vm_page_queues[PQ_CACHE + i].lcnt);
1860 db_printf("PQ_ACTIVE: %d, PQ_INACTIVE: %d\n",
1861 vm_page_queues[PQ_ACTIVE].lcnt,
1862 vm_page_queues[PQ_INACTIVE].lcnt);