2 * Copyright (c) 2002-2006 Rice University
3 * Copyright (c) 2007-2008 Alan L. Cox <alc@cs.rice.edu>
6 * This software was developed for the FreeBSD Project by Alan L. Cox,
7 * Olivier Crameri, Peter Druschel, Sitaram Iyer, and Juan Navarro.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
24 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
25 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
26 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
28 * WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
33 * Superpage reservation management module
35 * Any external functions defined by this module are only to be used by the
36 * virtual memory system.
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
44 #include <sys/param.h>
45 #include <sys/kernel.h>
47 #include <sys/malloc.h>
48 #include <sys/mutex.h>
49 #include <sys/queue.h>
50 #include <sys/rwlock.h>
52 #include <sys/sysctl.h>
53 #include <sys/systm.h>
56 #include <vm/vm_param.h>
57 #include <vm/vm_object.h>
58 #include <vm/vm_page.h>
59 #include <vm/vm_phys.h>
60 #include <vm/vm_radix.h>
61 #include <vm/vm_reserv.h>
64 * The reservation system supports the speculative allocation of large physical
65 * pages ("superpages"). Speculative allocation enables the fully-automatic
66 * utilization of superpages by the virtual memory system. In other words, no
67 * programmatic directives are required to use superpages.
70 #if VM_NRESERVLEVEL > 0
73 * The number of small pages that are contained in a level 0 reservation
75 #define VM_LEVEL_0_NPAGES (1 << VM_LEVEL_0_ORDER)
78 * The number of bits by which a physical address is shifted to obtain the
81 #define VM_LEVEL_0_SHIFT (VM_LEVEL_0_ORDER + PAGE_SHIFT)
84 * The size of a level 0 reservation in bytes
86 #define VM_LEVEL_0_SIZE (1 << VM_LEVEL_0_SHIFT)
89 * Computes the index of the small page underlying the given (object, pindex)
90 * within the reservation's array of small pages.
92 #define VM_RESERV_INDEX(object, pindex) \
93 (((object)->pg_color + (pindex)) & (VM_LEVEL_0_NPAGES - 1))
96 * The reservation structure
98 * A reservation structure is constructed whenever a large physical page is
99 * speculatively allocated to an object. The reservation provides the small
100 * physical pages for the range [pindex, pindex + VM_LEVEL_0_NPAGES) of offsets
101 * within that object. The reservation's "popcnt" tracks the number of these
102 * small physical pages that are in use at any given time. When and if the
103 * reservation is not fully utilized, it appears in the queue of partially-
104 * populated reservations. The reservation always appears on the containing
105 * object's list of reservations.
107 * A partially-populated reservation can be broken and reclaimed at any time.
110 TAILQ_ENTRY(vm_reserv) partpopq;
111 LIST_ENTRY(vm_reserv) objq;
112 vm_object_t object; /* containing object */
113 vm_pindex_t pindex; /* offset within object */
114 vm_page_t pages; /* first page of a superpage */
115 int popcnt; /* # of pages in use */
120 * The reservation array
122 * This array is analoguous in function to vm_page_array. It differs in the
123 * respect that it may contain a greater number of useful reservation
124 * structures than there are (physical) superpages. These "invalid"
125 * reservation structures exist to trade-off space for time in the
126 * implementation of vm_reserv_from_page(). Invalid reservation structures are
127 * distinguishable from "valid" reservation structures by inspecting the
128 * reservation's "pages" field. Invalid reservation structures have a NULL
131 * vm_reserv_from_page() maps a small (physical) page to an element of this
132 * array by computing a physical reservation number from the page's physical
133 * address. The physical reservation number is used as the array index.
135 * An "active" reservation is a valid reservation structure that has a non-NULL
136 * "object" field and a non-zero "popcnt" field. In other words, every active
137 * reservation belongs to a particular object. Moreover, every active
138 * reservation has an entry in the containing object's list of reservations.
140 static vm_reserv_t vm_reserv_array;
143 * The partially-populated reservation queue
145 * This queue enables the fast recovery of an unused cached or free small page
146 * from a partially-populated reservation. The reservation at the head of
147 * this queue is the least-recently-changed, partially-populated reservation.
149 * Access to this queue is synchronized by the free page queue lock.
151 static TAILQ_HEAD(, vm_reserv) vm_rvq_partpop =
152 TAILQ_HEAD_INITIALIZER(vm_rvq_partpop);
154 static SYSCTL_NODE(_vm, OID_AUTO, reserv, CTLFLAG_RD, 0, "Reservation Info");
156 static long vm_reserv_broken;
157 SYSCTL_LONG(_vm_reserv, OID_AUTO, broken, CTLFLAG_RD,
158 &vm_reserv_broken, 0, "Cumulative number of broken reservations");
160 static long vm_reserv_freed;
161 SYSCTL_LONG(_vm_reserv, OID_AUTO, freed, CTLFLAG_RD,
162 &vm_reserv_freed, 0, "Cumulative number of freed reservations");
164 static int sysctl_vm_reserv_partpopq(SYSCTL_HANDLER_ARGS);
166 SYSCTL_OID(_vm_reserv, OID_AUTO, partpopq, CTLTYPE_STRING | CTLFLAG_RD, NULL, 0,
167 sysctl_vm_reserv_partpopq, "A", "Partially-populated reservation queues");
169 static long vm_reserv_reclaimed;
170 SYSCTL_LONG(_vm_reserv, OID_AUTO, reclaimed, CTLFLAG_RD,
171 &vm_reserv_reclaimed, 0, "Cumulative number of reclaimed reservations");
173 static void vm_reserv_depopulate(vm_reserv_t rv);
174 static vm_reserv_t vm_reserv_from_page(vm_page_t m);
175 static boolean_t vm_reserv_has_pindex(vm_reserv_t rv,
177 static void vm_reserv_populate(vm_reserv_t rv);
178 static void vm_reserv_reclaim(vm_reserv_t rv);
181 * Describes the current state of the partially-populated reservation queue.
184 sysctl_vm_reserv_partpopq(SYSCTL_HANDLER_ARGS)
188 int counter, error, level, unused_pages;
190 error = sysctl_wire_old_buffer(req, 0);
193 sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
194 sbuf_printf(&sbuf, "\nLEVEL SIZE NUMBER\n\n");
195 for (level = -1; level <= VM_NRESERVLEVEL - 2; level++) {
198 mtx_lock(&vm_page_queue_free_mtx);
199 TAILQ_FOREACH(rv, &vm_rvq_partpop/*[level]*/, partpopq) {
201 unused_pages += VM_LEVEL_0_NPAGES - rv->popcnt;
203 mtx_unlock(&vm_page_queue_free_mtx);
204 sbuf_printf(&sbuf, "%5d: %6dK, %6d\n", level,
205 unused_pages * ((int)PAGE_SIZE / 1024), counter);
207 error = sbuf_finish(&sbuf);
213 * Reduces the given reservation's population count. If the population count
214 * becomes zero, the reservation is destroyed. Additionally, moves the
215 * reservation to the tail of the partially-populated reservations queue if the
216 * population count is non-zero.
218 * The free page queue lock must be held.
221 vm_reserv_depopulate(vm_reserv_t rv)
224 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
225 KASSERT(rv->object != NULL,
226 ("vm_reserv_depopulate: reserv %p is free", rv));
227 KASSERT(rv->popcnt > 0,
228 ("vm_reserv_depopulate: reserv %p's popcnt is corrupted", rv));
229 if (rv->inpartpopq) {
230 TAILQ_REMOVE(&vm_rvq_partpop, rv, partpopq);
231 rv->inpartpopq = FALSE;
233 KASSERT(rv->pages->psind == 1,
234 ("vm_reserv_depopulate: reserv %p is already demoted",
236 rv->pages->psind = 0;
239 if (rv->popcnt == 0) {
240 LIST_REMOVE(rv, objq);
242 vm_phys_free_pages(rv->pages, VM_LEVEL_0_ORDER);
245 rv->inpartpopq = TRUE;
246 TAILQ_INSERT_TAIL(&vm_rvq_partpop, rv, partpopq);
251 * Returns the reservation to which the given page might belong.
253 static __inline vm_reserv_t
254 vm_reserv_from_page(vm_page_t m)
257 return (&vm_reserv_array[VM_PAGE_TO_PHYS(m) >> VM_LEVEL_0_SHIFT]);
261 * Returns TRUE if the given reservation contains the given page index and
264 static __inline boolean_t
265 vm_reserv_has_pindex(vm_reserv_t rv, vm_pindex_t pindex)
268 return (((pindex - rv->pindex) & ~(VM_LEVEL_0_NPAGES - 1)) == 0);
272 * Increases the given reservation's population count. Moves the reservation
273 * to the tail of the partially-populated reservation queue.
275 * The free page queue must be locked.
278 vm_reserv_populate(vm_reserv_t rv)
281 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
282 KASSERT(rv->object != NULL,
283 ("vm_reserv_populate: reserv %p is free", rv));
284 KASSERT(rv->popcnt < VM_LEVEL_0_NPAGES,
285 ("vm_reserv_populate: reserv %p is already full", rv));
286 KASSERT(rv->pages->psind == 0,
287 ("vm_reserv_populate: reserv %p is already promoted", rv));
288 if (rv->inpartpopq) {
289 TAILQ_REMOVE(&vm_rvq_partpop, rv, partpopq);
290 rv->inpartpopq = FALSE;
293 if (rv->popcnt < VM_LEVEL_0_NPAGES) {
294 rv->inpartpopq = TRUE;
295 TAILQ_INSERT_TAIL(&vm_rvq_partpop, rv, partpopq);
297 rv->pages->psind = 1;
301 * Allocates a contiguous set of physical pages of the given size "npages"
302 * from existing or newly created reservations. All of the physical pages
303 * must be at or above the given physical address "low" and below the given
304 * physical address "high". The given value "alignment" determines the
305 * alignment of the first physical page in the set. If the given value
306 * "boundary" is non-zero, then the set of physical pages cannot cross any
307 * physical address boundary that is a multiple of that value. Both
308 * "alignment" and "boundary" must be a power of two.
310 * The object and free page queue must be locked.
313 vm_reserv_alloc_contig(vm_object_t object, vm_pindex_t pindex, u_long npages,
314 vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary)
317 vm_page_t m, m_ret, mpred, msucc;
318 vm_pindex_t first, leftcap, rightcap;
320 u_long allocpages, maxpages, minpages;
323 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
324 VM_OBJECT_ASSERT_WLOCKED(object);
325 KASSERT(npages != 0, ("vm_reserv_alloc_contig: npages is 0"));
328 * Is a reservation fundamentally impossible?
330 if (pindex < VM_RESERV_INDEX(object, pindex) ||
331 pindex + npages > object->size)
335 * All reservations of a particular size have the same alignment.
336 * Assuming that the first page is allocated from a reservation, the
337 * least significant bits of its physical address can be determined
338 * from its offset from the beginning of the reservation and the size
339 * of the reservation.
341 * Could the specified index within a reservation of the smallest
342 * possible size satisfy the alignment and boundary requirements?
344 pa = VM_RESERV_INDEX(object, pindex) << PAGE_SHIFT;
345 if ((pa & (alignment - 1)) != 0)
347 size = npages << PAGE_SHIFT;
348 if (((pa ^ (pa + size - 1)) & ~(boundary - 1)) != 0)
352 * Look for an existing reservation.
354 mpred = vm_radix_lookup_le(&object->rtree, pindex);
356 KASSERT(mpred->pindex < pindex,
357 ("vm_reserv_alloc_contig: pindex already allocated"));
358 rv = vm_reserv_from_page(mpred);
359 if (rv->object == object && vm_reserv_has_pindex(rv, pindex))
361 msucc = TAILQ_NEXT(mpred, listq);
363 msucc = TAILQ_FIRST(&object->memq);
365 KASSERT(msucc->pindex > pindex,
366 ("vm_reserv_alloc_page: pindex already allocated"));
367 rv = vm_reserv_from_page(msucc);
368 if (rv->object == object && vm_reserv_has_pindex(rv, pindex))
373 * Could at least one reservation fit between the first index to the
374 * left that can be used ("leftcap") and the first index to the right
375 * that cannot be used ("rightcap")?
377 first = pindex - VM_RESERV_INDEX(object, pindex);
379 if ((rv = vm_reserv_from_page(mpred))->object != object)
380 leftcap = mpred->pindex + 1;
382 leftcap = rv->pindex + VM_LEVEL_0_NPAGES;
386 minpages = VM_RESERV_INDEX(object, pindex) + npages;
387 maxpages = roundup2(minpages, VM_LEVEL_0_NPAGES);
388 allocpages = maxpages;
390 if ((rv = vm_reserv_from_page(msucc))->object != object)
391 rightcap = msucc->pindex;
393 rightcap = rv->pindex;
394 if (first + maxpages > rightcap) {
395 if (maxpages == VM_LEVEL_0_NPAGES)
399 * At least one reservation will fit between "leftcap"
400 * and "rightcap". However, a reservation for the
401 * last of the requested pages will not fit. Reduce
402 * the size of the upcoming allocation accordingly.
404 allocpages = minpages;
409 * Would the last new reservation extend past the end of the object?
411 if (first + maxpages > object->size) {
413 * Don't allocate the last new reservation if the object is a
414 * vnode or backed by another object that is a vnode.
416 if (object->type == OBJT_VNODE ||
417 (object->backing_object != NULL &&
418 object->backing_object->type == OBJT_VNODE)) {
419 if (maxpages == VM_LEVEL_0_NPAGES)
421 allocpages = minpages;
423 /* Speculate that the object may grow. */
427 * Allocate the physical pages. The alignment and boundary specified
428 * for this allocation may be different from the alignment and
429 * boundary specified for the requested pages. For instance, the
430 * specified index may not be the first page within the first new
433 m = vm_phys_alloc_contig(allocpages, low, high, ulmax(alignment,
434 VM_LEVEL_0_SIZE), boundary > VM_LEVEL_0_SIZE ? boundary : 0);
439 * The allocated physical pages always begin at a reservation
440 * boundary, but they do not always end at a reservation boundary.
441 * Initialize every reservation that is completely covered by the
442 * allocated physical pages.
445 index = VM_RESERV_INDEX(object, pindex);
447 rv = vm_reserv_from_page(m);
448 KASSERT(rv->pages == m,
449 ("vm_reserv_alloc_contig: reserv %p's pages is corrupted",
451 KASSERT(rv->object == NULL,
452 ("vm_reserv_alloc_contig: reserv %p isn't free", rv));
453 LIST_INSERT_HEAD(&object->rvq, rv, objq);
456 KASSERT(rv->popcnt == 0,
457 ("vm_reserv_alloc_contig: reserv %p's popcnt is corrupted",
459 KASSERT(!rv->inpartpopq,
460 ("vm_reserv_alloc_contig: reserv %p's inpartpopq is TRUE",
462 n = ulmin(VM_LEVEL_0_NPAGES - index, npages);
463 for (i = 0; i < n; i++)
464 vm_reserv_populate(rv);
467 m_ret = &rv->pages[index];
470 m += VM_LEVEL_0_NPAGES;
471 first += VM_LEVEL_0_NPAGES;
472 allocpages -= VM_LEVEL_0_NPAGES;
473 } while (allocpages >= VM_LEVEL_0_NPAGES);
477 * Found a matching reservation.
480 index = VM_RESERV_INDEX(object, pindex);
481 /* Does the allocation fit within the reservation? */
482 if (index + npages > VM_LEVEL_0_NPAGES)
484 m = &rv->pages[index];
485 pa = VM_PAGE_TO_PHYS(m);
486 if (pa < low || pa + size > high || (pa & (alignment - 1)) != 0 ||
487 ((pa ^ (pa + size - 1)) & ~(boundary - 1)) != 0)
489 /* Handle vm_page_rename(m, new_object, ...). */
490 for (i = 0; i < npages; i++)
491 if ((rv->pages[index + i].flags & (PG_CACHED | PG_FREE)) == 0)
493 for (i = 0; i < npages; i++)
494 vm_reserv_populate(rv);
499 * Allocates a page from an existing or newly-created reservation.
501 * The page "mpred" must immediately precede the offset "pindex" within the
504 * The object and free page queue must be locked.
507 vm_reserv_alloc_page(vm_object_t object, vm_pindex_t pindex, vm_page_t mpred)
510 vm_pindex_t first, leftcap, rightcap;
513 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
514 VM_OBJECT_ASSERT_WLOCKED(object);
517 * Is a reservation fundamentally impossible?
519 if (pindex < VM_RESERV_INDEX(object, pindex) ||
520 pindex >= object->size)
524 * Look for an existing reservation.
527 KASSERT(mpred->object == object,
528 ("vm_reserv_alloc_page: object doesn't contain mpred"));
529 KASSERT(mpred->pindex < pindex,
530 ("vm_reserv_alloc_page: mpred doesn't precede pindex"));
531 rv = vm_reserv_from_page(mpred);
532 if (rv->object == object && vm_reserv_has_pindex(rv, pindex))
534 msucc = TAILQ_NEXT(mpred, listq);
536 msucc = TAILQ_FIRST(&object->memq);
538 KASSERT(msucc->pindex > pindex,
539 ("vm_reserv_alloc_page: msucc doesn't succeed pindex"));
540 rv = vm_reserv_from_page(msucc);
541 if (rv->object == object && vm_reserv_has_pindex(rv, pindex))
546 * Could a reservation fit between the first index to the left that
547 * can be used and the first index to the right that cannot be used?
549 first = pindex - VM_RESERV_INDEX(object, pindex);
551 if ((rv = vm_reserv_from_page(mpred))->object != object)
552 leftcap = mpred->pindex + 1;
554 leftcap = rv->pindex + VM_LEVEL_0_NPAGES;
559 if ((rv = vm_reserv_from_page(msucc))->object != object)
560 rightcap = msucc->pindex;
562 rightcap = rv->pindex;
563 if (first + VM_LEVEL_0_NPAGES > rightcap)
568 * Would a new reservation extend past the end of the object?
570 if (first + VM_LEVEL_0_NPAGES > object->size) {
572 * Don't allocate a new reservation if the object is a vnode or
573 * backed by another object that is a vnode.
575 if (object->type == OBJT_VNODE ||
576 (object->backing_object != NULL &&
577 object->backing_object->type == OBJT_VNODE))
579 /* Speculate that the object may grow. */
583 * Allocate and populate the new reservation.
585 m = vm_phys_alloc_pages(VM_FREEPOOL_DEFAULT, VM_LEVEL_0_ORDER);
588 rv = vm_reserv_from_page(m);
589 KASSERT(rv->pages == m,
590 ("vm_reserv_alloc_page: reserv %p's pages is corrupted", rv));
591 KASSERT(rv->object == NULL,
592 ("vm_reserv_alloc_page: reserv %p isn't free", rv));
593 LIST_INSERT_HEAD(&object->rvq, rv, objq);
596 KASSERT(rv->popcnt == 0,
597 ("vm_reserv_alloc_page: reserv %p's popcnt is corrupted", rv));
598 KASSERT(!rv->inpartpopq,
599 ("vm_reserv_alloc_page: reserv %p's inpartpopq is TRUE", rv));
600 vm_reserv_populate(rv);
601 return (&rv->pages[VM_RESERV_INDEX(object, pindex)]);
604 * Found a matching reservation.
607 m = &rv->pages[VM_RESERV_INDEX(object, pindex)];
608 /* Handle vm_page_rename(m, new_object, ...). */
609 if ((m->flags & (PG_CACHED | PG_FREE)) == 0)
611 vm_reserv_populate(rv);
616 * Breaks all reservations belonging to the given object.
619 vm_reserv_break_all(vm_object_t object)
624 mtx_lock(&vm_page_queue_free_mtx);
625 while ((rv = LIST_FIRST(&object->rvq)) != NULL) {
626 KASSERT(rv->object == object,
627 ("vm_reserv_break_all: reserv %p is corrupted", rv));
628 if (rv->inpartpopq) {
629 TAILQ_REMOVE(&vm_rvq_partpop, rv, partpopq);
630 rv->inpartpopq = FALSE;
632 LIST_REMOVE(rv, objq);
634 for (i = 0; i < VM_LEVEL_0_NPAGES; i++) {
635 if ((rv->pages[i].flags & (PG_CACHED | PG_FREE)) != 0)
636 vm_phys_free_pages(&rv->pages[i], 0);
640 KASSERT(rv->popcnt == 0,
641 ("vm_reserv_break_all: reserv %p's popcnt is corrupted",
645 mtx_unlock(&vm_page_queue_free_mtx);
649 * Frees the given page if it belongs to a reservation. Returns TRUE if the
650 * page is freed and FALSE otherwise.
652 * The free page queue lock must be held.
655 vm_reserv_free_page(vm_page_t m)
659 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
660 rv = vm_reserv_from_page(m);
661 if (rv->object == NULL)
663 if ((m->flags & PG_CACHED) != 0 && m->pool != VM_FREEPOOL_CACHE)
664 vm_phys_set_pool(VM_FREEPOOL_CACHE, rv->pages,
666 vm_reserv_depopulate(rv);
671 * Initializes the reservation management system. Specifically, initializes
672 * the reservation array.
674 * Requires that vm_page_array and first_page are initialized!
683 * Initialize the reservation array. Specifically, initialize the
684 * "pages" field for every element that has an underlying superpage.
686 for (i = 0; phys_avail[i + 1] != 0; i += 2) {
687 paddr = roundup2(phys_avail[i], VM_LEVEL_0_SIZE);
688 while (paddr + VM_LEVEL_0_SIZE <= phys_avail[i + 1]) {
689 vm_reserv_array[paddr >> VM_LEVEL_0_SHIFT].pages =
690 PHYS_TO_VM_PAGE(paddr);
691 paddr += VM_LEVEL_0_SIZE;
697 * Returns a reservation level if the given page belongs to a fully-populated
698 * reservation and -1 otherwise.
701 vm_reserv_level_iffullpop(vm_page_t m)
705 rv = vm_reserv_from_page(m);
706 return (rv->popcnt == VM_LEVEL_0_NPAGES ? 0 : -1);
710 * Prepare for the reactivation of a cached page.
712 * First, suppose that the given page "m" was allocated individually, i.e., not
713 * as part of a reservation, and cached. Then, suppose a reservation
714 * containing "m" is allocated by the same object. Although "m" and the
715 * reservation belong to the same object, "m"'s pindex may not match the
718 * The free page queue must be locked.
721 vm_reserv_reactivate_page(vm_page_t m)
726 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
727 rv = vm_reserv_from_page(m);
728 if (rv->object == NULL)
730 KASSERT((m->flags & PG_CACHED) != 0,
731 ("vm_reserv_uncache_page: page %p is not cached", m));
732 if (m->object == rv->object &&
733 m->pindex - rv->pindex == VM_RESERV_INDEX(m->object, m->pindex))
734 vm_reserv_populate(rv);
736 KASSERT(rv->inpartpopq,
737 ("vm_reserv_uncache_page: reserv %p's inpartpopq is FALSE",
739 TAILQ_REMOVE(&vm_rvq_partpop, rv, partpopq);
740 rv->inpartpopq = FALSE;
741 LIST_REMOVE(rv, objq);
743 /* Don't vm_phys_free_pages(m, 0). */
744 m_index = m - rv->pages;
745 for (i = 0; i < m_index; i++) {
746 if ((rv->pages[i].flags & (PG_CACHED | PG_FREE)) != 0)
747 vm_phys_free_pages(&rv->pages[i], 0);
751 for (i++; i < VM_LEVEL_0_NPAGES; i++) {
752 if ((rv->pages[i].flags & (PG_CACHED | PG_FREE)) != 0)
753 vm_phys_free_pages(&rv->pages[i], 0);
757 KASSERT(rv->popcnt == 0,
758 ("vm_reserv_uncache_page: reserv %p's popcnt is corrupted",
766 * Breaks the given partially-populated reservation, releasing its cached and
767 * free pages to the physical memory allocator.
769 * The free page queue lock must be held.
772 vm_reserv_reclaim(vm_reserv_t rv)
776 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
777 KASSERT(rv->inpartpopq,
778 ("vm_reserv_reclaim: reserv %p's inpartpopq is corrupted", rv));
779 TAILQ_REMOVE(&vm_rvq_partpop, rv, partpopq);
780 rv->inpartpopq = FALSE;
781 KASSERT(rv->object != NULL,
782 ("vm_reserv_reclaim: reserv %p is free", rv));
783 LIST_REMOVE(rv, objq);
785 for (i = 0; i < VM_LEVEL_0_NPAGES; i++) {
786 if ((rv->pages[i].flags & (PG_CACHED | PG_FREE)) != 0)
787 vm_phys_free_pages(&rv->pages[i], 0);
791 KASSERT(rv->popcnt == 0,
792 ("vm_reserv_reclaim: reserv %p's popcnt is corrupted", rv));
793 vm_reserv_reclaimed++;
797 * Breaks the reservation at the head of the partially-populated reservation
798 * queue, releasing its cached and free pages to the physical memory
799 * allocator. Returns TRUE if a reservation is broken and FALSE otherwise.
801 * The free page queue lock must be held.
804 vm_reserv_reclaim_inactive(void)
808 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
809 if ((rv = TAILQ_FIRST(&vm_rvq_partpop)) != NULL) {
810 vm_reserv_reclaim(rv);
817 * Searches the partially-populated reservation queue for the least recently
818 * active reservation with unused pages, i.e., cached or free, that satisfy the
819 * given request for contiguous physical memory. If a satisfactory reservation
820 * is found, it is broken. Returns TRUE if a reservation is broken and FALSE
823 * The free page queue lock must be held.
826 vm_reserv_reclaim_contig(u_long npages, vm_paddr_t low, vm_paddr_t high,
827 u_long alignment, vm_paddr_t boundary)
829 vm_paddr_t pa, pa_length, size;
833 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
834 if (npages > VM_LEVEL_0_NPAGES - 1)
836 size = npages << PAGE_SHIFT;
837 TAILQ_FOREACH(rv, &vm_rvq_partpop, partpopq) {
838 pa = VM_PAGE_TO_PHYS(&rv->pages[VM_LEVEL_0_NPAGES - 1]);
839 if (pa + PAGE_SIZE - size < low) {
840 /* this entire reservation is too low; go to next */
844 for (i = 0; i < VM_LEVEL_0_NPAGES; i++)
845 if ((rv->pages[i].flags & (PG_CACHED | PG_FREE)) != 0) {
846 pa_length += PAGE_SIZE;
847 if (pa_length == PAGE_SIZE) {
848 pa = VM_PAGE_TO_PHYS(&rv->pages[i]);
849 if (pa + size > high) {
850 /* skip to next reservation */
852 } else if (pa < low ||
853 (pa & (alignment - 1)) != 0 ||
854 ((pa ^ (pa + size - 1)) &
855 ~(boundary - 1)) != 0)
858 if (pa_length >= size) {
859 vm_reserv_reclaim(rv);
869 * Transfers the reservation underlying the given page to a new object.
871 * The object must be locked.
874 vm_reserv_rename(vm_page_t m, vm_object_t new_object, vm_object_t old_object,
875 vm_pindex_t old_object_offset)
879 VM_OBJECT_ASSERT_WLOCKED(new_object);
880 rv = vm_reserv_from_page(m);
881 if (rv->object == old_object) {
882 mtx_lock(&vm_page_queue_free_mtx);
883 if (rv->object == old_object) {
884 LIST_REMOVE(rv, objq);
885 LIST_INSERT_HEAD(&new_object->rvq, rv, objq);
886 rv->object = new_object;
887 rv->pindex -= old_object_offset;
889 mtx_unlock(&vm_page_queue_free_mtx);
894 * Allocates the virtual and physical memory required by the reservation
895 * management system's data structures, in particular, the reservation array.
898 vm_reserv_startup(vm_offset_t *vaddr, vm_paddr_t end, vm_paddr_t high_water)
904 * Calculate the size (in bytes) of the reservation array. Round up
905 * from "high_water" because every small page is mapped to an element
906 * in the reservation array based on its physical address. Thus, the
907 * number of elements in the reservation array can be greater than the
908 * number of superpages.
910 size = howmany(high_water, VM_LEVEL_0_SIZE) * sizeof(struct vm_reserv);
913 * Allocate and map the physical memory for the reservation array. The
914 * next available virtual address is returned by reference.
916 new_end = end - round_page(size);
917 vm_reserv_array = (void *)(uintptr_t)pmap_map(vaddr, new_end, end,
918 VM_PROT_READ | VM_PROT_WRITE);
919 bzero(vm_reserv_array, size);
922 * Return the next available physical address.
927 #endif /* VM_NRESERVLEVEL > 0 */