longer used. More precisely, they are always zero because the code that decremented and incremented them no longer exists. Bump __FreeBSD_version to mark this change. Reviewed by: kib, markj Sponsored by: Dell EMC Isilon Differential Revision: https://reviews.freebsd.org/D8583
3564 lines
92 KiB
C
3564 lines
92 KiB
C
/*-
|
|
* Copyright (c) 1991 Regents of the University of California.
|
|
* All rights reserved.
|
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* Copyright (c) 1998 Matthew Dillon. All Rights Reserved.
|
|
*
|
|
* This code is derived from software contributed to Berkeley by
|
|
* The Mach Operating System project at Carnegie-Mellon University.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
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*
|
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* from: @(#)vm_page.c 7.4 (Berkeley) 5/7/91
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|
*/
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|
|
|
/*-
|
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* Copyright (c) 1987, 1990 Carnegie-Mellon University.
|
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* All rights reserved.
|
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*
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|
* Authors: Avadis Tevanian, Jr., Michael Wayne Young
|
|
*
|
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* Permission to use, copy, modify and distribute this software and
|
|
* its documentation is hereby granted, provided that both the copyright
|
|
* notice and this permission notice appear in all copies of the
|
|
* software, derivative works or modified versions, and any portions
|
|
* thereof, and that both notices appear in supporting documentation.
|
|
*
|
|
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
|
|
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
|
|
* FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
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|
*
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|
* Carnegie Mellon requests users of this software to return to
|
|
*
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|
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
|
|
* School of Computer Science
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|
* Carnegie Mellon University
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* Pittsburgh PA 15213-3890
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*
|
|
* any improvements or extensions that they make and grant Carnegie the
|
|
* rights to redistribute these changes.
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|
*/
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|
|
|
/*
|
|
* GENERAL RULES ON VM_PAGE MANIPULATION
|
|
*
|
|
* - A page queue lock is required when adding or removing a page from a
|
|
* page queue regardless of other locks or the busy state of a page.
|
|
*
|
|
* * In general, no thread besides the page daemon can acquire or
|
|
* hold more than one page queue lock at a time.
|
|
*
|
|
* * The page daemon can acquire and hold any pair of page queue
|
|
* locks in any order.
|
|
*
|
|
* - The object lock is required when inserting or removing
|
|
* pages from an object (vm_page_insert() or vm_page_remove()).
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*
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|
*/
|
|
|
|
/*
|
|
* Resident memory management module.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
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|
__FBSDID("$FreeBSD$");
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|
|
|
#include "opt_vm.h"
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|
|
|
#include <sys/param.h>
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|
#include <sys/systm.h>
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|
#include <sys/lock.h>
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|
#include <sys/kernel.h>
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|
#include <sys/limits.h>
|
|
#include <sys/linker.h>
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|
#include <sys/malloc.h>
|
|
#include <sys/mman.h>
|
|
#include <sys/msgbuf.h>
|
|
#include <sys/mutex.h>
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|
#include <sys/proc.h>
|
|
#include <sys/rwlock.h>
|
|
#include <sys/sbuf.h>
|
|
#include <sys/smp.h>
|
|
#include <sys/sysctl.h>
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|
#include <sys/vmmeter.h>
|
|
#include <sys/vnode.h>
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|
|
|
#include <vm/vm.h>
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|
#include <vm/pmap.h>
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|
#include <vm/vm_param.h>
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|
#include <vm/vm_kern.h>
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|
#include <vm/vm_object.h>
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|
#include <vm/vm_page.h>
|
|
#include <vm/vm_pageout.h>
|
|
#include <vm/vm_pager.h>
|
|
#include <vm/vm_phys.h>
|
|
#include <vm/vm_radix.h>
|
|
#include <vm/vm_reserv.h>
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|
#include <vm/vm_extern.h>
|
|
#include <vm/uma.h>
|
|
#include <vm/uma_int.h>
|
|
|
|
#include <machine/md_var.h>
|
|
|
|
/*
|
|
* Associated with page of user-allocatable memory is a
|
|
* page structure.
|
|
*/
|
|
|
|
struct vm_domain vm_dom[MAXMEMDOM];
|
|
struct mtx_padalign vm_page_queue_free_mtx;
|
|
|
|
struct mtx_padalign pa_lock[PA_LOCK_COUNT];
|
|
|
|
vm_page_t vm_page_array;
|
|
long vm_page_array_size;
|
|
long first_page;
|
|
|
|
static int boot_pages = UMA_BOOT_PAGES;
|
|
SYSCTL_INT(_vm, OID_AUTO, boot_pages, CTLFLAG_RDTUN | CTLFLAG_NOFETCH,
|
|
&boot_pages, 0,
|
|
"number of pages allocated for bootstrapping the VM system");
|
|
|
|
static int pa_tryrelock_restart;
|
|
SYSCTL_INT(_vm, OID_AUTO, tryrelock_restart, CTLFLAG_RD,
|
|
&pa_tryrelock_restart, 0, "Number of tryrelock restarts");
|
|
|
|
static TAILQ_HEAD(, vm_page) blacklist_head;
|
|
static int sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS);
|
|
SYSCTL_PROC(_vm, OID_AUTO, page_blacklist, CTLTYPE_STRING | CTLFLAG_RD |
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|
CTLFLAG_MPSAFE, NULL, 0, sysctl_vm_page_blacklist, "A", "Blacklist pages");
|
|
|
|
/* Is the page daemon waiting for free pages? */
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|
static int vm_pageout_pages_needed;
|
|
|
|
static uma_zone_t fakepg_zone;
|
|
|
|
static void vm_page_alloc_check(vm_page_t m);
|
|
static void vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits);
|
|
static void vm_page_enqueue(uint8_t queue, vm_page_t m);
|
|
static void vm_page_free_wakeup(void);
|
|
static void vm_page_init_fakepg(void *dummy);
|
|
static int vm_page_insert_after(vm_page_t m, vm_object_t object,
|
|
vm_pindex_t pindex, vm_page_t mpred);
|
|
static void vm_page_insert_radixdone(vm_page_t m, vm_object_t object,
|
|
vm_page_t mpred);
|
|
static int vm_page_reclaim_run(int req_class, u_long npages, vm_page_t m_run,
|
|
vm_paddr_t high);
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|
|
|
SYSINIT(vm_page, SI_SUB_VM, SI_ORDER_SECOND, vm_page_init_fakepg, NULL);
|
|
|
|
static void
|
|
vm_page_init_fakepg(void *dummy)
|
|
{
|
|
|
|
fakepg_zone = uma_zcreate("fakepg", sizeof(struct vm_page), NULL, NULL,
|
|
NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE | UMA_ZONE_VM);
|
|
}
|
|
|
|
/* Make sure that u_long is at least 64 bits when PAGE_SIZE is 32K. */
|
|
#if PAGE_SIZE == 32768
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#ifdef CTASSERT
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|
CTASSERT(sizeof(u_long) >= 8);
|
|
#endif
|
|
#endif
|
|
|
|
/*
|
|
* Try to acquire a physical address lock while a pmap is locked. If we
|
|
* fail to trylock we unlock and lock the pmap directly and cache the
|
|
* locked pa in *locked. The caller should then restart their loop in case
|
|
* the virtual to physical mapping has changed.
|
|
*/
|
|
int
|
|
vm_page_pa_tryrelock(pmap_t pmap, vm_paddr_t pa, vm_paddr_t *locked)
|
|
{
|
|
vm_paddr_t lockpa;
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|
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|
lockpa = *locked;
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|
*locked = pa;
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|
if (lockpa) {
|
|
PA_LOCK_ASSERT(lockpa, MA_OWNED);
|
|
if (PA_LOCKPTR(pa) == PA_LOCKPTR(lockpa))
|
|
return (0);
|
|
PA_UNLOCK(lockpa);
|
|
}
|
|
if (PA_TRYLOCK(pa))
|
|
return (0);
|
|
PMAP_UNLOCK(pmap);
|
|
atomic_add_int(&pa_tryrelock_restart, 1);
|
|
PA_LOCK(pa);
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|
PMAP_LOCK(pmap);
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|
return (EAGAIN);
|
|
}
|
|
|
|
/*
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|
* vm_set_page_size:
|
|
*
|
|
* Sets the page size, perhaps based upon the memory
|
|
* size. Must be called before any use of page-size
|
|
* dependent functions.
|
|
*/
|
|
void
|
|
vm_set_page_size(void)
|
|
{
|
|
if (vm_cnt.v_page_size == 0)
|
|
vm_cnt.v_page_size = PAGE_SIZE;
|
|
if (((vm_cnt.v_page_size - 1) & vm_cnt.v_page_size) != 0)
|
|
panic("vm_set_page_size: page size not a power of two");
|
|
}
|
|
|
|
/*
|
|
* vm_page_blacklist_next:
|
|
*
|
|
* Find the next entry in the provided string of blacklist
|
|
* addresses. Entries are separated by space, comma, or newline.
|
|
* If an invalid integer is encountered then the rest of the
|
|
* string is skipped. Updates the list pointer to the next
|
|
* character, or NULL if the string is exhausted or invalid.
|
|
*/
|
|
static vm_paddr_t
|
|
vm_page_blacklist_next(char **list, char *end)
|
|
{
|
|
vm_paddr_t bad;
|
|
char *cp, *pos;
|
|
|
|
if (list == NULL || *list == NULL)
|
|
return (0);
|
|
if (**list =='\0') {
|
|
*list = NULL;
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|
return (0);
|
|
}
|
|
|
|
/*
|
|
* If there's no end pointer then the buffer is coming from
|
|
* the kenv and we know it's null-terminated.
|
|
*/
|
|
if (end == NULL)
|
|
end = *list + strlen(*list);
|
|
|
|
/* Ensure that strtoq() won't walk off the end */
|
|
if (*end != '\0') {
|
|
if (*end == '\n' || *end == ' ' || *end == ',')
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*end = '\0';
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|
else {
|
|
printf("Blacklist not terminated, skipping\n");
|
|
*list = NULL;
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|
return (0);
|
|
}
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|
}
|
|
|
|
for (pos = *list; *pos != '\0'; pos = cp) {
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|
bad = strtoq(pos, &cp, 0);
|
|
if (*cp == '\0' || *cp == ' ' || *cp == ',' || *cp == '\n') {
|
|
if (bad == 0) {
|
|
if (++cp < end)
|
|
continue;
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|
else
|
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break;
|
|
}
|
|
} else
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|
break;
|
|
if (*cp == '\0' || ++cp >= end)
|
|
*list = NULL;
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|
else
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|
*list = cp;
|
|
return (trunc_page(bad));
|
|
}
|
|
printf("Garbage in RAM blacklist, skipping\n");
|
|
*list = NULL;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* vm_page_blacklist_check:
|
|
*
|
|
* Iterate through the provided string of blacklist addresses, pulling
|
|
* each entry out of the physical allocator free list and putting it
|
|
* onto a list for reporting via the vm.page_blacklist sysctl.
|
|
*/
|
|
static void
|
|
vm_page_blacklist_check(char *list, char *end)
|
|
{
|
|
vm_paddr_t pa;
|
|
vm_page_t m;
|
|
char *next;
|
|
int ret;
|
|
|
|
next = list;
|
|
while (next != NULL) {
|
|
if ((pa = vm_page_blacklist_next(&next, end)) == 0)
|
|
continue;
|
|
m = vm_phys_paddr_to_vm_page(pa);
|
|
if (m == NULL)
|
|
continue;
|
|
mtx_lock(&vm_page_queue_free_mtx);
|
|
ret = vm_phys_unfree_page(m);
|
|
mtx_unlock(&vm_page_queue_free_mtx);
|
|
if (ret == TRUE) {
|
|
TAILQ_INSERT_TAIL(&blacklist_head, m, listq);
|
|
if (bootverbose)
|
|
printf("Skipping page with pa 0x%jx\n",
|
|
(uintmax_t)pa);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* vm_page_blacklist_load:
|
|
*
|
|
* Search for a special module named "ram_blacklist". It'll be a
|
|
* plain text file provided by the user via the loader directive
|
|
* of the same name.
|
|
*/
|
|
static void
|
|
vm_page_blacklist_load(char **list, char **end)
|
|
{
|
|
void *mod;
|
|
u_char *ptr;
|
|
u_int len;
|
|
|
|
mod = NULL;
|
|
ptr = NULL;
|
|
|
|
mod = preload_search_by_type("ram_blacklist");
|
|
if (mod != NULL) {
|
|
ptr = preload_fetch_addr(mod);
|
|
len = preload_fetch_size(mod);
|
|
}
|
|
*list = ptr;
|
|
if (ptr != NULL)
|
|
*end = ptr + len;
|
|
else
|
|
*end = NULL;
|
|
return;
|
|
}
|
|
|
|
static int
|
|
sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
vm_page_t m;
|
|
struct sbuf sbuf;
|
|
int error, first;
|
|
|
|
first = 1;
|
|
error = sysctl_wire_old_buffer(req, 0);
|
|
if (error != 0)
|
|
return (error);
|
|
sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
|
|
TAILQ_FOREACH(m, &blacklist_head, listq) {
|
|
sbuf_printf(&sbuf, "%s%#jx", first ? "" : ",",
|
|
(uintmax_t)m->phys_addr);
|
|
first = 0;
|
|
}
|
|
error = sbuf_finish(&sbuf);
|
|
sbuf_delete(&sbuf);
|
|
return (error);
|
|
}
|
|
|
|
static void
|
|
vm_page_domain_init(struct vm_domain *vmd)
|
|
{
|
|
struct vm_pagequeue *pq;
|
|
int i;
|
|
|
|
*__DECONST(char **, &vmd->vmd_pagequeues[PQ_INACTIVE].pq_name) =
|
|
"vm inactive pagequeue";
|
|
*__DECONST(u_int **, &vmd->vmd_pagequeues[PQ_INACTIVE].pq_vcnt) =
|
|
&vm_cnt.v_inactive_count;
|
|
*__DECONST(char **, &vmd->vmd_pagequeues[PQ_ACTIVE].pq_name) =
|
|
"vm active pagequeue";
|
|
*__DECONST(u_int **, &vmd->vmd_pagequeues[PQ_ACTIVE].pq_vcnt) =
|
|
&vm_cnt.v_active_count;
|
|
*__DECONST(char **, &vmd->vmd_pagequeues[PQ_LAUNDRY].pq_name) =
|
|
"vm laundry pagequeue";
|
|
*__DECONST(int **, &vmd->vmd_pagequeues[PQ_LAUNDRY].pq_vcnt) =
|
|
&vm_cnt.v_laundry_count;
|
|
vmd->vmd_page_count = 0;
|
|
vmd->vmd_free_count = 0;
|
|
vmd->vmd_segs = 0;
|
|
vmd->vmd_oom = FALSE;
|
|
for (i = 0; i < PQ_COUNT; i++) {
|
|
pq = &vmd->vmd_pagequeues[i];
|
|
TAILQ_INIT(&pq->pq_pl);
|
|
mtx_init(&pq->pq_mutex, pq->pq_name, "vm pagequeue",
|
|
MTX_DEF | MTX_DUPOK);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* vm_page_startup:
|
|
*
|
|
* Initializes the resident memory module.
|
|
*
|
|
* Allocates memory for the page cells, and
|
|
* for the object/offset-to-page hash table headers.
|
|
* Each page cell is initialized and placed on the free list.
|
|
*/
|
|
vm_offset_t
|
|
vm_page_startup(vm_offset_t vaddr)
|
|
{
|
|
vm_offset_t mapped;
|
|
vm_paddr_t page_range;
|
|
vm_paddr_t new_end;
|
|
int i;
|
|
vm_paddr_t pa;
|
|
vm_paddr_t last_pa;
|
|
char *list, *listend;
|
|
vm_paddr_t end;
|
|
vm_paddr_t biggestsize;
|
|
vm_paddr_t low_water, high_water;
|
|
int biggestone;
|
|
int pages_per_zone;
|
|
|
|
biggestsize = 0;
|
|
biggestone = 0;
|
|
vaddr = round_page(vaddr);
|
|
|
|
for (i = 0; phys_avail[i + 1]; i += 2) {
|
|
phys_avail[i] = round_page(phys_avail[i]);
|
|
phys_avail[i + 1] = trunc_page(phys_avail[i + 1]);
|
|
}
|
|
|
|
low_water = phys_avail[0];
|
|
high_water = phys_avail[1];
|
|
|
|
for (i = 0; i < vm_phys_nsegs; i++) {
|
|
if (vm_phys_segs[i].start < low_water)
|
|
low_water = vm_phys_segs[i].start;
|
|
if (vm_phys_segs[i].end > high_water)
|
|
high_water = vm_phys_segs[i].end;
|
|
}
|
|
for (i = 0; phys_avail[i + 1]; i += 2) {
|
|
vm_paddr_t size = phys_avail[i + 1] - phys_avail[i];
|
|
|
|
if (size > biggestsize) {
|
|
biggestone = i;
|
|
biggestsize = size;
|
|
}
|
|
if (phys_avail[i] < low_water)
|
|
low_water = phys_avail[i];
|
|
if (phys_avail[i + 1] > high_water)
|
|
high_water = phys_avail[i + 1];
|
|
}
|
|
|
|
end = phys_avail[biggestone+1];
|
|
|
|
/*
|
|
* Initialize the page and queue locks.
|
|
*/
|
|
mtx_init(&vm_page_queue_free_mtx, "vm page free queue", NULL, MTX_DEF);
|
|
for (i = 0; i < PA_LOCK_COUNT; i++)
|
|
mtx_init(&pa_lock[i], "vm page", NULL, MTX_DEF);
|
|
for (i = 0; i < vm_ndomains; i++)
|
|
vm_page_domain_init(&vm_dom[i]);
|
|
|
|
/*
|
|
* Almost all of the pages needed for boot strapping UMA are used
|
|
* for zone structures, so if the number of CPUs results in those
|
|
* structures taking more than one page each, we set aside more pages
|
|
* in proportion to the zone structure size.
|
|
*/
|
|
pages_per_zone = howmany(sizeof(struct uma_zone) +
|
|
sizeof(struct uma_cache) * (mp_maxid + 1), UMA_SLAB_SIZE);
|
|
if (pages_per_zone > 1) {
|
|
/* Reserve more pages so that we don't run out. */
|
|
boot_pages = UMA_BOOT_PAGES_ZONES * pages_per_zone;
|
|
}
|
|
|
|
/*
|
|
* Allocate memory for use when boot strapping the kernel memory
|
|
* allocator.
|
|
*
|
|
* CTFLAG_RDTUN doesn't work during the early boot process, so we must
|
|
* manually fetch the value.
|
|
*/
|
|
TUNABLE_INT_FETCH("vm.boot_pages", &boot_pages);
|
|
new_end = end - (boot_pages * UMA_SLAB_SIZE);
|
|
new_end = trunc_page(new_end);
|
|
mapped = pmap_map(&vaddr, new_end, end,
|
|
VM_PROT_READ | VM_PROT_WRITE);
|
|
bzero((void *)mapped, end - new_end);
|
|
uma_startup((void *)mapped, boot_pages);
|
|
|
|
#if defined(__aarch64__) || defined(__amd64__) || defined(__arm__) || \
|
|
defined(__i386__) || defined(__mips__)
|
|
/*
|
|
* Allocate a bitmap to indicate that a random physical page
|
|
* needs to be included in a minidump.
|
|
*
|
|
* The amd64 port needs this to indicate which direct map pages
|
|
* need to be dumped, via calls to dump_add_page()/dump_drop_page().
|
|
*
|
|
* However, i386 still needs this workspace internally within the
|
|
* minidump code. In theory, they are not needed on i386, but are
|
|
* included should the sf_buf code decide to use them.
|
|
*/
|
|
last_pa = 0;
|
|
for (i = 0; dump_avail[i + 1] != 0; i += 2)
|
|
if (dump_avail[i + 1] > last_pa)
|
|
last_pa = dump_avail[i + 1];
|
|
page_range = last_pa / PAGE_SIZE;
|
|
vm_page_dump_size = round_page(roundup2(page_range, NBBY) / NBBY);
|
|
new_end -= vm_page_dump_size;
|
|
vm_page_dump = (void *)(uintptr_t)pmap_map(&vaddr, new_end,
|
|
new_end + vm_page_dump_size, VM_PROT_READ | VM_PROT_WRITE);
|
|
bzero((void *)vm_page_dump, vm_page_dump_size);
|
|
#endif
|
|
#ifdef __amd64__
|
|
/*
|
|
* Request that the physical pages underlying the message buffer be
|
|
* included in a crash dump. Since the message buffer is accessed
|
|
* through the direct map, they are not automatically included.
|
|
*/
|
|
pa = DMAP_TO_PHYS((vm_offset_t)msgbufp->msg_ptr);
|
|
last_pa = pa + round_page(msgbufsize);
|
|
while (pa < last_pa) {
|
|
dump_add_page(pa);
|
|
pa += PAGE_SIZE;
|
|
}
|
|
#endif
|
|
/*
|
|
* Compute the number of pages of memory that will be available for
|
|
* use (taking into account the overhead of a page structure per
|
|
* page).
|
|
*/
|
|
first_page = low_water / PAGE_SIZE;
|
|
#ifdef VM_PHYSSEG_SPARSE
|
|
page_range = 0;
|
|
for (i = 0; i < vm_phys_nsegs; i++) {
|
|
page_range += atop(vm_phys_segs[i].end -
|
|
vm_phys_segs[i].start);
|
|
}
|
|
for (i = 0; phys_avail[i + 1] != 0; i += 2)
|
|
page_range += atop(phys_avail[i + 1] - phys_avail[i]);
|
|
#elif defined(VM_PHYSSEG_DENSE)
|
|
page_range = high_water / PAGE_SIZE - first_page;
|
|
#else
|
|
#error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined."
|
|
#endif
|
|
end = new_end;
|
|
|
|
/*
|
|
* Reserve an unmapped guard page to trap access to vm_page_array[-1].
|
|
*/
|
|
vaddr += PAGE_SIZE;
|
|
|
|
/*
|
|
* Initialize the mem entry structures now, and put them in the free
|
|
* queue.
|
|
*/
|
|
new_end = trunc_page(end - page_range * sizeof(struct vm_page));
|
|
mapped = pmap_map(&vaddr, new_end, end,
|
|
VM_PROT_READ | VM_PROT_WRITE);
|
|
vm_page_array = (vm_page_t) mapped;
|
|
#if VM_NRESERVLEVEL > 0
|
|
/*
|
|
* Allocate memory for the reservation management system's data
|
|
* structures.
|
|
*/
|
|
new_end = vm_reserv_startup(&vaddr, new_end, high_water);
|
|
#endif
|
|
#if defined(__aarch64__) || defined(__amd64__) || defined(__mips__)
|
|
/*
|
|
* pmap_map on arm64, amd64, and mips can come out of the direct-map,
|
|
* not kvm like i386, so the pages must be tracked for a crashdump to
|
|
* include this data. This includes the vm_page_array and the early
|
|
* UMA bootstrap pages.
|
|
*/
|
|
for (pa = new_end; pa < phys_avail[biggestone + 1]; pa += PAGE_SIZE)
|
|
dump_add_page(pa);
|
|
#endif
|
|
phys_avail[biggestone + 1] = new_end;
|
|
|
|
/*
|
|
* Add physical memory segments corresponding to the available
|
|
* physical pages.
|
|
*/
|
|
for (i = 0; phys_avail[i + 1] != 0; i += 2)
|
|
vm_phys_add_seg(phys_avail[i], phys_avail[i + 1]);
|
|
|
|
/*
|
|
* Clear all of the page structures
|
|
*/
|
|
bzero((caddr_t) vm_page_array, page_range * sizeof(struct vm_page));
|
|
for (i = 0; i < page_range; i++)
|
|
vm_page_array[i].order = VM_NFREEORDER;
|
|
vm_page_array_size = page_range;
|
|
|
|
/*
|
|
* Initialize the physical memory allocator.
|
|
*/
|
|
vm_phys_init();
|
|
|
|
/*
|
|
* Add every available physical page that is not blacklisted to
|
|
* the free lists.
|
|
*/
|
|
vm_cnt.v_page_count = 0;
|
|
vm_cnt.v_free_count = 0;
|
|
for (i = 0; phys_avail[i + 1] != 0; i += 2) {
|
|
pa = phys_avail[i];
|
|
last_pa = phys_avail[i + 1];
|
|
while (pa < last_pa) {
|
|
vm_phys_add_page(pa);
|
|
pa += PAGE_SIZE;
|
|
}
|
|
}
|
|
|
|
TAILQ_INIT(&blacklist_head);
|
|
vm_page_blacklist_load(&list, &listend);
|
|
vm_page_blacklist_check(list, listend);
|
|
|
|
list = kern_getenv("vm.blacklist");
|
|
vm_page_blacklist_check(list, NULL);
|
|
|
|
freeenv(list);
|
|
#if VM_NRESERVLEVEL > 0
|
|
/*
|
|
* Initialize the reservation management system.
|
|
*/
|
|
vm_reserv_init();
|
|
#endif
|
|
return (vaddr);
|
|
}
|
|
|
|
void
|
|
vm_page_reference(vm_page_t m)
|
|
{
|
|
|
|
vm_page_aflag_set(m, PGA_REFERENCED);
|
|
}
|
|
|
|
/*
|
|
* vm_page_busy_downgrade:
|
|
*
|
|
* Downgrade an exclusive busy page into a single shared busy page.
|
|
*/
|
|
void
|
|
vm_page_busy_downgrade(vm_page_t m)
|
|
{
|
|
u_int x;
|
|
bool locked;
|
|
|
|
vm_page_assert_xbusied(m);
|
|
locked = mtx_owned(vm_page_lockptr(m));
|
|
|
|
for (;;) {
|
|
x = m->busy_lock;
|
|
x &= VPB_BIT_WAITERS;
|
|
if (x != 0 && !locked)
|
|
vm_page_lock(m);
|
|
if (atomic_cmpset_rel_int(&m->busy_lock,
|
|
VPB_SINGLE_EXCLUSIVER | x, VPB_SHARERS_WORD(1)))
|
|
break;
|
|
if (x != 0 && !locked)
|
|
vm_page_unlock(m);
|
|
}
|
|
if (x != 0) {
|
|
wakeup(m);
|
|
if (!locked)
|
|
vm_page_unlock(m);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* vm_page_sbusied:
|
|
*
|
|
* Return a positive value if the page is shared busied, 0 otherwise.
|
|
*/
|
|
int
|
|
vm_page_sbusied(vm_page_t m)
|
|
{
|
|
u_int x;
|
|
|
|
x = m->busy_lock;
|
|
return ((x & VPB_BIT_SHARED) != 0 && x != VPB_UNBUSIED);
|
|
}
|
|
|
|
/*
|
|
* vm_page_sunbusy:
|
|
*
|
|
* Shared unbusy a page.
|
|
*/
|
|
void
|
|
vm_page_sunbusy(vm_page_t m)
|
|
{
|
|
u_int x;
|
|
|
|
vm_page_assert_sbusied(m);
|
|
|
|
for (;;) {
|
|
x = m->busy_lock;
|
|
if (VPB_SHARERS(x) > 1) {
|
|
if (atomic_cmpset_int(&m->busy_lock, x,
|
|
x - VPB_ONE_SHARER))
|
|
break;
|
|
continue;
|
|
}
|
|
if ((x & VPB_BIT_WAITERS) == 0) {
|
|
KASSERT(x == VPB_SHARERS_WORD(1),
|
|
("vm_page_sunbusy: invalid lock state"));
|
|
if (atomic_cmpset_int(&m->busy_lock,
|
|
VPB_SHARERS_WORD(1), VPB_UNBUSIED))
|
|
break;
|
|
continue;
|
|
}
|
|
KASSERT(x == (VPB_SHARERS_WORD(1) | VPB_BIT_WAITERS),
|
|
("vm_page_sunbusy: invalid lock state for waiters"));
|
|
|
|
vm_page_lock(m);
|
|
if (!atomic_cmpset_int(&m->busy_lock, x, VPB_UNBUSIED)) {
|
|
vm_page_unlock(m);
|
|
continue;
|
|
}
|
|
wakeup(m);
|
|
vm_page_unlock(m);
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* vm_page_busy_sleep:
|
|
*
|
|
* Sleep and release the page lock, using the page pointer as wchan.
|
|
* This is used to implement the hard-path of busying mechanism.
|
|
*
|
|
* The given page must be locked.
|
|
*
|
|
* If nonshared is true, sleep only if the page is xbusy.
|
|
*/
|
|
void
|
|
vm_page_busy_sleep(vm_page_t m, const char *wmesg, bool nonshared)
|
|
{
|
|
u_int x;
|
|
|
|
vm_page_assert_locked(m);
|
|
|
|
x = m->busy_lock;
|
|
if (x == VPB_UNBUSIED || (nonshared && (x & VPB_BIT_SHARED) != 0) ||
|
|
((x & VPB_BIT_WAITERS) == 0 &&
|
|
!atomic_cmpset_int(&m->busy_lock, x, x | VPB_BIT_WAITERS))) {
|
|
vm_page_unlock(m);
|
|
return;
|
|
}
|
|
msleep(m, vm_page_lockptr(m), PVM | PDROP, wmesg, 0);
|
|
}
|
|
|
|
/*
|
|
* vm_page_trysbusy:
|
|
*
|
|
* Try to shared busy a page.
|
|
* If the operation succeeds 1 is returned otherwise 0.
|
|
* The operation never sleeps.
|
|
*/
|
|
int
|
|
vm_page_trysbusy(vm_page_t m)
|
|
{
|
|
u_int x;
|
|
|
|
for (;;) {
|
|
x = m->busy_lock;
|
|
if ((x & VPB_BIT_SHARED) == 0)
|
|
return (0);
|
|
if (atomic_cmpset_acq_int(&m->busy_lock, x, x + VPB_ONE_SHARER))
|
|
return (1);
|
|
}
|
|
}
|
|
|
|
static void
|
|
vm_page_xunbusy_locked(vm_page_t m)
|
|
{
|
|
|
|
vm_page_assert_xbusied(m);
|
|
vm_page_assert_locked(m);
|
|
|
|
atomic_store_rel_int(&m->busy_lock, VPB_UNBUSIED);
|
|
/* There is a waiter, do wakeup() instead of vm_page_flash(). */
|
|
wakeup(m);
|
|
}
|
|
|
|
void
|
|
vm_page_xunbusy_maybelocked(vm_page_t m)
|
|
{
|
|
bool lockacq;
|
|
|
|
vm_page_assert_xbusied(m);
|
|
|
|
/*
|
|
* Fast path for unbusy. If it succeeds, we know that there
|
|
* are no waiters, so we do not need a wakeup.
|
|
*/
|
|
if (atomic_cmpset_rel_int(&m->busy_lock, VPB_SINGLE_EXCLUSIVER,
|
|
VPB_UNBUSIED))
|
|
return;
|
|
|
|
lockacq = !mtx_owned(vm_page_lockptr(m));
|
|
if (lockacq)
|
|
vm_page_lock(m);
|
|
vm_page_xunbusy_locked(m);
|
|
if (lockacq)
|
|
vm_page_unlock(m);
|
|
}
|
|
|
|
/*
|
|
* vm_page_xunbusy_hard:
|
|
*
|
|
* Called after the first try the exclusive unbusy of a page failed.
|
|
* It is assumed that the waiters bit is on.
|
|
*/
|
|
void
|
|
vm_page_xunbusy_hard(vm_page_t m)
|
|
{
|
|
|
|
vm_page_assert_xbusied(m);
|
|
|
|
vm_page_lock(m);
|
|
vm_page_xunbusy_locked(m);
|
|
vm_page_unlock(m);
|
|
}
|
|
|
|
/*
|
|
* vm_page_flash:
|
|
*
|
|
* Wakeup anyone waiting for the page.
|
|
* The ownership bits do not change.
|
|
*
|
|
* The given page must be locked.
|
|
*/
|
|
void
|
|
vm_page_flash(vm_page_t m)
|
|
{
|
|
u_int x;
|
|
|
|
vm_page_lock_assert(m, MA_OWNED);
|
|
|
|
for (;;) {
|
|
x = m->busy_lock;
|
|
if ((x & VPB_BIT_WAITERS) == 0)
|
|
return;
|
|
if (atomic_cmpset_int(&m->busy_lock, x,
|
|
x & (~VPB_BIT_WAITERS)))
|
|
break;
|
|
}
|
|
wakeup(m);
|
|
}
|
|
|
|
/*
|
|
* Keep page from being freed by the page daemon
|
|
* much of the same effect as wiring, except much lower
|
|
* overhead and should be used only for *very* temporary
|
|
* holding ("wiring").
|
|
*/
|
|
void
|
|
vm_page_hold(vm_page_t mem)
|
|
{
|
|
|
|
vm_page_lock_assert(mem, MA_OWNED);
|
|
mem->hold_count++;
|
|
}
|
|
|
|
void
|
|
vm_page_unhold(vm_page_t mem)
|
|
{
|
|
|
|
vm_page_lock_assert(mem, MA_OWNED);
|
|
KASSERT(mem->hold_count >= 1, ("vm_page_unhold: hold count < 0!!!"));
|
|
--mem->hold_count;
|
|
if (mem->hold_count == 0 && (mem->flags & PG_UNHOLDFREE) != 0)
|
|
vm_page_free_toq(mem);
|
|
}
|
|
|
|
/*
|
|
* vm_page_unhold_pages:
|
|
*
|
|
* Unhold each of the pages that is referenced by the given array.
|
|
*/
|
|
void
|
|
vm_page_unhold_pages(vm_page_t *ma, int count)
|
|
{
|
|
struct mtx *mtx, *new_mtx;
|
|
|
|
mtx = NULL;
|
|
for (; count != 0; count--) {
|
|
/*
|
|
* Avoid releasing and reacquiring the same page lock.
|
|
*/
|
|
new_mtx = vm_page_lockptr(*ma);
|
|
if (mtx != new_mtx) {
|
|
if (mtx != NULL)
|
|
mtx_unlock(mtx);
|
|
mtx = new_mtx;
|
|
mtx_lock(mtx);
|
|
}
|
|
vm_page_unhold(*ma);
|
|
ma++;
|
|
}
|
|
if (mtx != NULL)
|
|
mtx_unlock(mtx);
|
|
}
|
|
|
|
vm_page_t
|
|
PHYS_TO_VM_PAGE(vm_paddr_t pa)
|
|
{
|
|
vm_page_t m;
|
|
|
|
#ifdef VM_PHYSSEG_SPARSE
|
|
m = vm_phys_paddr_to_vm_page(pa);
|
|
if (m == NULL)
|
|
m = vm_phys_fictitious_to_vm_page(pa);
|
|
return (m);
|
|
#elif defined(VM_PHYSSEG_DENSE)
|
|
long pi;
|
|
|
|
pi = atop(pa);
|
|
if (pi >= first_page && (pi - first_page) < vm_page_array_size) {
|
|
m = &vm_page_array[pi - first_page];
|
|
return (m);
|
|
}
|
|
return (vm_phys_fictitious_to_vm_page(pa));
|
|
#else
|
|
#error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined."
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* vm_page_getfake:
|
|
*
|
|
* Create a fictitious page with the specified physical address and
|
|
* memory attribute. The memory attribute is the only the machine-
|
|
* dependent aspect of a fictitious page that must be initialized.
|
|
*/
|
|
vm_page_t
|
|
vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr)
|
|
{
|
|
vm_page_t m;
|
|
|
|
m = uma_zalloc(fakepg_zone, M_WAITOK | M_ZERO);
|
|
vm_page_initfake(m, paddr, memattr);
|
|
return (m);
|
|
}
|
|
|
|
void
|
|
vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr)
|
|
{
|
|
|
|
if ((m->flags & PG_FICTITIOUS) != 0) {
|
|
/*
|
|
* The page's memattr might have changed since the
|
|
* previous initialization. Update the pmap to the
|
|
* new memattr.
|
|
*/
|
|
goto memattr;
|
|
}
|
|
m->phys_addr = paddr;
|
|
m->queue = PQ_NONE;
|
|
/* Fictitious pages don't use "segind". */
|
|
m->flags = PG_FICTITIOUS;
|
|
/* Fictitious pages don't use "order" or "pool". */
|
|
m->oflags = VPO_UNMANAGED;
|
|
m->busy_lock = VPB_SINGLE_EXCLUSIVER;
|
|
m->wire_count = 1;
|
|
pmap_page_init(m);
|
|
memattr:
|
|
pmap_page_set_memattr(m, memattr);
|
|
}
|
|
|
|
/*
|
|
* vm_page_putfake:
|
|
*
|
|
* Release a fictitious page.
|
|
*/
|
|
void
|
|
vm_page_putfake(vm_page_t m)
|
|
{
|
|
|
|
KASSERT((m->oflags & VPO_UNMANAGED) != 0, ("managed %p", m));
|
|
KASSERT((m->flags & PG_FICTITIOUS) != 0,
|
|
("vm_page_putfake: bad page %p", m));
|
|
uma_zfree(fakepg_zone, m);
|
|
}
|
|
|
|
/*
|
|
* vm_page_updatefake:
|
|
*
|
|
* Update the given fictitious page to the specified physical address and
|
|
* memory attribute.
|
|
*/
|
|
void
|
|
vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr)
|
|
{
|
|
|
|
KASSERT((m->flags & PG_FICTITIOUS) != 0,
|
|
("vm_page_updatefake: bad page %p", m));
|
|
m->phys_addr = paddr;
|
|
pmap_page_set_memattr(m, memattr);
|
|
}
|
|
|
|
/*
|
|
* vm_page_free:
|
|
*
|
|
* Free a page.
|
|
*/
|
|
void
|
|
vm_page_free(vm_page_t m)
|
|
{
|
|
|
|
m->flags &= ~PG_ZERO;
|
|
vm_page_free_toq(m);
|
|
}
|
|
|
|
/*
|
|
* vm_page_free_zero:
|
|
*
|
|
* Free a page to the zerod-pages queue
|
|
*/
|
|
void
|
|
vm_page_free_zero(vm_page_t m)
|
|
{
|
|
|
|
m->flags |= PG_ZERO;
|
|
vm_page_free_toq(m);
|
|
}
|
|
|
|
/*
|
|
* Unbusy and handle the page queueing for a page from a getpages request that
|
|
* was optionally read ahead or behind.
|
|
*/
|
|
void
|
|
vm_page_readahead_finish(vm_page_t m)
|
|
{
|
|
|
|
/* We shouldn't put invalid pages on queues. */
|
|
KASSERT(m->valid != 0, ("%s: %p is invalid", __func__, m));
|
|
|
|
/*
|
|
* Since the page is not the actually needed one, whether it should
|
|
* be activated or deactivated is not obvious. Empirical results
|
|
* have shown that deactivating the page is usually the best choice,
|
|
* unless the page is wanted by another thread.
|
|
*/
|
|
vm_page_lock(m);
|
|
if ((m->busy_lock & VPB_BIT_WAITERS) != 0)
|
|
vm_page_activate(m);
|
|
else
|
|
vm_page_deactivate(m);
|
|
vm_page_unlock(m);
|
|
vm_page_xunbusy(m);
|
|
}
|
|
|
|
/*
|
|
* vm_page_sleep_if_busy:
|
|
*
|
|
* Sleep and release the page queues lock if the page is busied.
|
|
* Returns TRUE if the thread slept.
|
|
*
|
|
* The given page must be unlocked and object containing it must
|
|
* be locked.
|
|
*/
|
|
int
|
|
vm_page_sleep_if_busy(vm_page_t m, const char *msg)
|
|
{
|
|
vm_object_t obj;
|
|
|
|
vm_page_lock_assert(m, MA_NOTOWNED);
|
|
VM_OBJECT_ASSERT_WLOCKED(m->object);
|
|
|
|
if (vm_page_busied(m)) {
|
|
/*
|
|
* The page-specific object must be cached because page
|
|
* identity can change during the sleep, causing the
|
|
* re-lock of a different object.
|
|
* It is assumed that a reference to the object is already
|
|
* held by the callers.
|
|
*/
|
|
obj = m->object;
|
|
vm_page_lock(m);
|
|
VM_OBJECT_WUNLOCK(obj);
|
|
vm_page_busy_sleep(m, msg, false);
|
|
VM_OBJECT_WLOCK(obj);
|
|
return (TRUE);
|
|
}
|
|
return (FALSE);
|
|
}
|
|
|
|
/*
|
|
* vm_page_dirty_KBI: [ internal use only ]
|
|
*
|
|
* Set all bits in the page's dirty field.
|
|
*
|
|
* The object containing the specified page must be locked if the
|
|
* call is made from the machine-independent layer.
|
|
*
|
|
* See vm_page_clear_dirty_mask().
|
|
*
|
|
* This function should only be called by vm_page_dirty().
|
|
*/
|
|
void
|
|
vm_page_dirty_KBI(vm_page_t m)
|
|
{
|
|
|
|
/* Refer to this operation by its public name. */
|
|
KASSERT(m->valid == VM_PAGE_BITS_ALL,
|
|
("vm_page_dirty: page is invalid!"));
|
|
m->dirty = VM_PAGE_BITS_ALL;
|
|
}
|
|
|
|
/*
|
|
* vm_page_insert: [ internal use only ]
|
|
*
|
|
* Inserts the given mem entry into the object and object list.
|
|
*
|
|
* The object must be locked.
|
|
*/
|
|
int
|
|
vm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex)
|
|
{
|
|
vm_page_t mpred;
|
|
|
|
VM_OBJECT_ASSERT_WLOCKED(object);
|
|
mpred = vm_radix_lookup_le(&object->rtree, pindex);
|
|
return (vm_page_insert_after(m, object, pindex, mpred));
|
|
}
|
|
|
|
/*
|
|
* vm_page_insert_after:
|
|
*
|
|
* Inserts the page "m" into the specified object at offset "pindex".
|
|
*
|
|
* The page "mpred" must immediately precede the offset "pindex" within
|
|
* the specified object.
|
|
*
|
|
* The object must be locked.
|
|
*/
|
|
static int
|
|
vm_page_insert_after(vm_page_t m, vm_object_t object, vm_pindex_t pindex,
|
|
vm_page_t mpred)
|
|
{
|
|
vm_page_t msucc;
|
|
|
|
VM_OBJECT_ASSERT_WLOCKED(object);
|
|
KASSERT(m->object == NULL,
|
|
("vm_page_insert_after: page already inserted"));
|
|
if (mpred != NULL) {
|
|
KASSERT(mpred->object == object,
|
|
("vm_page_insert_after: object doesn't contain mpred"));
|
|
KASSERT(mpred->pindex < pindex,
|
|
("vm_page_insert_after: mpred doesn't precede pindex"));
|
|
msucc = TAILQ_NEXT(mpred, listq);
|
|
} else
|
|
msucc = TAILQ_FIRST(&object->memq);
|
|
if (msucc != NULL)
|
|
KASSERT(msucc->pindex > pindex,
|
|
("vm_page_insert_after: msucc doesn't succeed pindex"));
|
|
|
|
/*
|
|
* Record the object/offset pair in this page
|
|
*/
|
|
m->object = object;
|
|
m->pindex = pindex;
|
|
|
|
/*
|
|
* Now link into the object's ordered list of backed pages.
|
|
*/
|
|
if (vm_radix_insert(&object->rtree, m)) {
|
|
m->object = NULL;
|
|
m->pindex = 0;
|
|
return (1);
|
|
}
|
|
vm_page_insert_radixdone(m, object, mpred);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* vm_page_insert_radixdone:
|
|
*
|
|
* Complete page "m" insertion into the specified object after the
|
|
* radix trie hooking.
|
|
*
|
|
* The page "mpred" must precede the offset "m->pindex" within the
|
|
* specified object.
|
|
*
|
|
* The object must be locked.
|
|
*/
|
|
static void
|
|
vm_page_insert_radixdone(vm_page_t m, vm_object_t object, vm_page_t mpred)
|
|
{
|
|
|
|
VM_OBJECT_ASSERT_WLOCKED(object);
|
|
KASSERT(object != NULL && m->object == object,
|
|
("vm_page_insert_radixdone: page %p has inconsistent object", m));
|
|
if (mpred != NULL) {
|
|
KASSERT(mpred->object == object,
|
|
("vm_page_insert_after: object doesn't contain mpred"));
|
|
KASSERT(mpred->pindex < m->pindex,
|
|
("vm_page_insert_after: mpred doesn't precede pindex"));
|
|
}
|
|
|
|
if (mpred != NULL)
|
|
TAILQ_INSERT_AFTER(&object->memq, mpred, m, listq);
|
|
else
|
|
TAILQ_INSERT_HEAD(&object->memq, m, listq);
|
|
|
|
/*
|
|
* Show that the object has one more resident page.
|
|
*/
|
|
object->resident_page_count++;
|
|
|
|
/*
|
|
* Hold the vnode until the last page is released.
|
|
*/
|
|
if (object->resident_page_count == 1 && object->type == OBJT_VNODE)
|
|
vhold(object->handle);
|
|
|
|
/*
|
|
* Since we are inserting a new and possibly dirty page,
|
|
* update the object's OBJ_MIGHTBEDIRTY flag.
|
|
*/
|
|
if (pmap_page_is_write_mapped(m))
|
|
vm_object_set_writeable_dirty(object);
|
|
}
|
|
|
|
/*
|
|
* vm_page_remove:
|
|
*
|
|
* Removes the given mem entry from the object/offset-page
|
|
* table and the object page list, but do not invalidate/terminate
|
|
* the backing store.
|
|
*
|
|
* The object must be locked. The page must be locked if it is managed.
|
|
*/
|
|
void
|
|
vm_page_remove(vm_page_t m)
|
|
{
|
|
vm_object_t object;
|
|
|
|
if ((m->oflags & VPO_UNMANAGED) == 0)
|
|
vm_page_assert_locked(m);
|
|
if ((object = m->object) == NULL)
|
|
return;
|
|
VM_OBJECT_ASSERT_WLOCKED(object);
|
|
if (vm_page_xbusied(m))
|
|
vm_page_xunbusy_maybelocked(m);
|
|
|
|
/*
|
|
* Now remove from the object's list of backed pages.
|
|
*/
|
|
vm_radix_remove(&object->rtree, m->pindex);
|
|
TAILQ_REMOVE(&object->memq, m, listq);
|
|
|
|
/*
|
|
* And show that the object has one fewer resident page.
|
|
*/
|
|
object->resident_page_count--;
|
|
|
|
/*
|
|
* The vnode may now be recycled.
|
|
*/
|
|
if (object->resident_page_count == 0 && object->type == OBJT_VNODE)
|
|
vdrop(object->handle);
|
|
|
|
m->object = NULL;
|
|
}
|
|
|
|
/*
|
|
* vm_page_lookup:
|
|
*
|
|
* Returns the page associated with the object/offset
|
|
* pair specified; if none is found, NULL is returned.
|
|
*
|
|
* The object must be locked.
|
|
*/
|
|
vm_page_t
|
|
vm_page_lookup(vm_object_t object, vm_pindex_t pindex)
|
|
{
|
|
|
|
VM_OBJECT_ASSERT_LOCKED(object);
|
|
return (vm_radix_lookup(&object->rtree, pindex));
|
|
}
|
|
|
|
/*
|
|
* vm_page_find_least:
|
|
*
|
|
* Returns the page associated with the object with least pindex
|
|
* greater than or equal to the parameter pindex, or NULL.
|
|
*
|
|
* The object must be locked.
|
|
*/
|
|
vm_page_t
|
|
vm_page_find_least(vm_object_t object, vm_pindex_t pindex)
|
|
{
|
|
vm_page_t m;
|
|
|
|
VM_OBJECT_ASSERT_LOCKED(object);
|
|
if ((m = TAILQ_FIRST(&object->memq)) != NULL && m->pindex < pindex)
|
|
m = vm_radix_lookup_ge(&object->rtree, pindex);
|
|
return (m);
|
|
}
|
|
|
|
/*
|
|
* Returns the given page's successor (by pindex) within the object if it is
|
|
* resident; if none is found, NULL is returned.
|
|
*
|
|
* The object must be locked.
|
|
*/
|
|
vm_page_t
|
|
vm_page_next(vm_page_t m)
|
|
{
|
|
vm_page_t next;
|
|
|
|
VM_OBJECT_ASSERT_LOCKED(m->object);
|
|
if ((next = TAILQ_NEXT(m, listq)) != NULL &&
|
|
next->pindex != m->pindex + 1)
|
|
next = NULL;
|
|
return (next);
|
|
}
|
|
|
|
/*
|
|
* Returns the given page's predecessor (by pindex) within the object if it is
|
|
* resident; if none is found, NULL is returned.
|
|
*
|
|
* The object must be locked.
|
|
*/
|
|
vm_page_t
|
|
vm_page_prev(vm_page_t m)
|
|
{
|
|
vm_page_t prev;
|
|
|
|
VM_OBJECT_ASSERT_LOCKED(m->object);
|
|
if ((prev = TAILQ_PREV(m, pglist, listq)) != NULL &&
|
|
prev->pindex != m->pindex - 1)
|
|
prev = NULL;
|
|
return (prev);
|
|
}
|
|
|
|
/*
|
|
* Uses the page mnew as a replacement for an existing page at index
|
|
* pindex which must be already present in the object.
|
|
*
|
|
* The existing page must not be on a paging queue.
|
|
*/
|
|
vm_page_t
|
|
vm_page_replace(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex)
|
|
{
|
|
vm_page_t mold;
|
|
|
|
VM_OBJECT_ASSERT_WLOCKED(object);
|
|
KASSERT(mnew->object == NULL,
|
|
("vm_page_replace: page already in object"));
|
|
|
|
/*
|
|
* This function mostly follows vm_page_insert() and
|
|
* vm_page_remove() without the radix, object count and vnode
|
|
* dance. Double check such functions for more comments.
|
|
*/
|
|
|
|
mnew->object = object;
|
|
mnew->pindex = pindex;
|
|
mold = vm_radix_replace(&object->rtree, mnew);
|
|
KASSERT(mold->queue == PQ_NONE,
|
|
("vm_page_replace: mold is on a paging queue"));
|
|
|
|
/* Keep the resident page list in sorted order. */
|
|
TAILQ_INSERT_AFTER(&object->memq, mold, mnew, listq);
|
|
TAILQ_REMOVE(&object->memq, mold, listq);
|
|
|
|
mold->object = NULL;
|
|
vm_page_xunbusy_maybelocked(mold);
|
|
|
|
/*
|
|
* The object's resident_page_count does not change because we have
|
|
* swapped one page for another, but OBJ_MIGHTBEDIRTY.
|
|
*/
|
|
if (pmap_page_is_write_mapped(mnew))
|
|
vm_object_set_writeable_dirty(object);
|
|
return (mold);
|
|
}
|
|
|
|
/*
|
|
* vm_page_rename:
|
|
*
|
|
* Move the given memory entry from its
|
|
* current object to the specified target object/offset.
|
|
*
|
|
* Note: swap associated with the page must be invalidated by the move. We
|
|
* have to do this for several reasons: (1) we aren't freeing the
|
|
* page, (2) we are dirtying the page, (3) the VM system is probably
|
|
* moving the page from object A to B, and will then later move
|
|
* the backing store from A to B and we can't have a conflict.
|
|
*
|
|
* Note: we *always* dirty the page. It is necessary both for the
|
|
* fact that we moved it, and because we may be invalidating
|
|
* swap. If the page is on the cache, we have to deactivate it
|
|
* or vm_page_dirty() will panic. Dirty pages are not allowed
|
|
* on the cache.
|
|
*
|
|
* The objects must be locked.
|
|
*/
|
|
int
|
|
vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex)
|
|
{
|
|
vm_page_t mpred;
|
|
vm_pindex_t opidx;
|
|
|
|
VM_OBJECT_ASSERT_WLOCKED(new_object);
|
|
|
|
mpred = vm_radix_lookup_le(&new_object->rtree, new_pindex);
|
|
KASSERT(mpred == NULL || mpred->pindex != new_pindex,
|
|
("vm_page_rename: pindex already renamed"));
|
|
|
|
/*
|
|
* Create a custom version of vm_page_insert() which does not depend
|
|
* by m_prev and can cheat on the implementation aspects of the
|
|
* function.
|
|
*/
|
|
opidx = m->pindex;
|
|
m->pindex = new_pindex;
|
|
if (vm_radix_insert(&new_object->rtree, m)) {
|
|
m->pindex = opidx;
|
|
return (1);
|
|
}
|
|
|
|
/*
|
|
* The operation cannot fail anymore. The removal must happen before
|
|
* the listq iterator is tainted.
|
|
*/
|
|
m->pindex = opidx;
|
|
vm_page_lock(m);
|
|
vm_page_remove(m);
|
|
|
|
/* Return back to the new pindex to complete vm_page_insert(). */
|
|
m->pindex = new_pindex;
|
|
m->object = new_object;
|
|
vm_page_unlock(m);
|
|
vm_page_insert_radixdone(m, new_object, mpred);
|
|
vm_page_dirty(m);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* vm_page_alloc:
|
|
*
|
|
* Allocate and return a page that is associated with the specified
|
|
* object and offset pair. By default, this page is exclusive busied.
|
|
*
|
|
* The caller must always specify an allocation class.
|
|
*
|
|
* allocation classes:
|
|
* VM_ALLOC_NORMAL normal process request
|
|
* VM_ALLOC_SYSTEM system *really* needs a page
|
|
* VM_ALLOC_INTERRUPT interrupt time request
|
|
*
|
|
* optional allocation flags:
|
|
* VM_ALLOC_COUNT(number) the number of additional pages that the caller
|
|
* intends to allocate
|
|
* VM_ALLOC_NOBUSY do not exclusive busy the page
|
|
* VM_ALLOC_NODUMP do not include the page in a kernel core dump
|
|
* VM_ALLOC_NOOBJ page is not associated with an object and
|
|
* should not be exclusive busy
|
|
* VM_ALLOC_SBUSY shared busy the allocated page
|
|
* VM_ALLOC_WIRED wire the allocated page
|
|
* VM_ALLOC_ZERO prefer a zeroed page
|
|
*
|
|
* This routine may not sleep.
|
|
*/
|
|
vm_page_t
|
|
vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req)
|
|
{
|
|
vm_page_t m, mpred;
|
|
int flags, req_class;
|
|
|
|
mpred = 0; /* XXX: pacify gcc */
|
|
KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) &&
|
|
(object != NULL || (req & VM_ALLOC_SBUSY) == 0) &&
|
|
((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) !=
|
|
(VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)),
|
|
("vm_page_alloc: inconsistent object(%p)/req(%x)", (void *)object,
|
|
req));
|
|
if (object != NULL)
|
|
VM_OBJECT_ASSERT_WLOCKED(object);
|
|
|
|
req_class = req & VM_ALLOC_CLASS_MASK;
|
|
|
|
/*
|
|
* The page daemon is allowed to dig deeper into the free page list.
|
|
*/
|
|
if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT)
|
|
req_class = VM_ALLOC_SYSTEM;
|
|
|
|
if (object != NULL) {
|
|
mpred = vm_radix_lookup_le(&object->rtree, pindex);
|
|
KASSERT(mpred == NULL || mpred->pindex != pindex,
|
|
("vm_page_alloc: pindex already allocated"));
|
|
}
|
|
|
|
/*
|
|
* The page allocation request can came from consumers which already
|
|
* hold the free page queue mutex, like vm_page_insert() in
|
|
* vm_page_cache().
|
|
*/
|
|
mtx_lock_flags(&vm_page_queue_free_mtx, MTX_RECURSE);
|
|
if (vm_cnt.v_free_count > vm_cnt.v_free_reserved ||
|
|
(req_class == VM_ALLOC_SYSTEM &&
|
|
vm_cnt.v_free_count > vm_cnt.v_interrupt_free_min) ||
|
|
(req_class == VM_ALLOC_INTERRUPT &&
|
|
vm_cnt.v_free_count > 0)) {
|
|
/*
|
|
* Allocate from the free queue if the number of free pages
|
|
* exceeds the minimum for the request class.
|
|
*/
|
|
#if VM_NRESERVLEVEL > 0
|
|
if (object == NULL || (object->flags & (OBJ_COLORED |
|
|
OBJ_FICTITIOUS)) != OBJ_COLORED || (m =
|
|
vm_reserv_alloc_page(object, pindex, mpred)) == NULL)
|
|
#endif
|
|
{
|
|
m = vm_phys_alloc_pages(object != NULL ?
|
|
VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT, 0);
|
|
#if VM_NRESERVLEVEL > 0
|
|
if (m == NULL && vm_reserv_reclaim_inactive()) {
|
|
m = vm_phys_alloc_pages(object != NULL ?
|
|
VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT,
|
|
0);
|
|
}
|
|
#endif
|
|
}
|
|
} else {
|
|
/*
|
|
* Not allocatable, give up.
|
|
*/
|
|
mtx_unlock(&vm_page_queue_free_mtx);
|
|
atomic_add_int(&vm_pageout_deficit,
|
|
max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1));
|
|
pagedaemon_wakeup();
|
|
return (NULL);
|
|
}
|
|
|
|
/*
|
|
* At this point we had better have found a good page.
|
|
*/
|
|
KASSERT(m != NULL, ("vm_page_alloc: missing page"));
|
|
vm_phys_freecnt_adj(m, -1);
|
|
mtx_unlock(&vm_page_queue_free_mtx);
|
|
vm_page_alloc_check(m);
|
|
|
|
/*
|
|
* Initialize the page. Only the PG_ZERO flag is inherited.
|
|
*/
|
|
flags = 0;
|
|
if ((req & VM_ALLOC_ZERO) != 0)
|
|
flags = PG_ZERO;
|
|
flags &= m->flags;
|
|
if ((req & VM_ALLOC_NODUMP) != 0)
|
|
flags |= PG_NODUMP;
|
|
m->flags = flags;
|
|
m->aflags = 0;
|
|
m->oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ?
|
|
VPO_UNMANAGED : 0;
|
|
m->busy_lock = VPB_UNBUSIED;
|
|
if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0)
|
|
m->busy_lock = VPB_SINGLE_EXCLUSIVER;
|
|
if ((req & VM_ALLOC_SBUSY) != 0)
|
|
m->busy_lock = VPB_SHARERS_WORD(1);
|
|
if (req & VM_ALLOC_WIRED) {
|
|
/*
|
|
* The page lock is not required for wiring a page until that
|
|
* page is inserted into the object.
|
|
*/
|
|
atomic_add_int(&vm_cnt.v_wire_count, 1);
|
|
m->wire_count = 1;
|
|
}
|
|
m->act_count = 0;
|
|
|
|
if (object != NULL) {
|
|
if (vm_page_insert_after(m, object, pindex, mpred)) {
|
|
pagedaemon_wakeup();
|
|
if (req & VM_ALLOC_WIRED) {
|
|
atomic_subtract_int(&vm_cnt.v_wire_count, 1);
|
|
m->wire_count = 0;
|
|
}
|
|
m->object = NULL;
|
|
m->oflags = VPO_UNMANAGED;
|
|
m->busy_lock = VPB_UNBUSIED;
|
|
vm_page_free(m);
|
|
return (NULL);
|
|
}
|
|
|
|
/* Ignore device objects; the pager sets "memattr" for them. */
|
|
if (object->memattr != VM_MEMATTR_DEFAULT &&
|
|
(object->flags & OBJ_FICTITIOUS) == 0)
|
|
pmap_page_set_memattr(m, object->memattr);
|
|
} else
|
|
m->pindex = pindex;
|
|
|
|
/*
|
|
* Don't wakeup too often - wakeup the pageout daemon when
|
|
* we would be nearly out of memory.
|
|
*/
|
|
if (vm_paging_needed())
|
|
pagedaemon_wakeup();
|
|
|
|
return (m);
|
|
}
|
|
|
|
/*
|
|
* vm_page_alloc_contig:
|
|
*
|
|
* Allocate a contiguous set of physical pages of the given size "npages"
|
|
* from the free lists. All of the physical pages must be at or above
|
|
* the given physical address "low" and below the given physical address
|
|
* "high". The given value "alignment" determines the alignment of the
|
|
* first physical page in the set. If the given value "boundary" is
|
|
* non-zero, then the set of physical pages cannot cross any physical
|
|
* address boundary that is a multiple of that value. Both "alignment"
|
|
* and "boundary" must be a power of two.
|
|
*
|
|
* If the specified memory attribute, "memattr", is VM_MEMATTR_DEFAULT,
|
|
* then the memory attribute setting for the physical pages is configured
|
|
* to the object's memory attribute setting. Otherwise, the memory
|
|
* attribute setting for the physical pages is configured to "memattr",
|
|
* overriding the object's memory attribute setting. However, if the
|
|
* object's memory attribute setting is not VM_MEMATTR_DEFAULT, then the
|
|
* memory attribute setting for the physical pages cannot be configured
|
|
* to VM_MEMATTR_DEFAULT.
|
|
*
|
|
* The caller must always specify an allocation class.
|
|
*
|
|
* allocation classes:
|
|
* VM_ALLOC_NORMAL normal process request
|
|
* VM_ALLOC_SYSTEM system *really* needs a page
|
|
* VM_ALLOC_INTERRUPT interrupt time request
|
|
*
|
|
* optional allocation flags:
|
|
* VM_ALLOC_NOBUSY do not exclusive busy the page
|
|
* VM_ALLOC_NODUMP do not include the page in a kernel core dump
|
|
* VM_ALLOC_NOOBJ page is not associated with an object and
|
|
* should not be exclusive busy
|
|
* VM_ALLOC_SBUSY shared busy the allocated page
|
|
* VM_ALLOC_WIRED wire the allocated page
|
|
* VM_ALLOC_ZERO prefer a zeroed page
|
|
*
|
|
* This routine may not sleep.
|
|
*/
|
|
vm_page_t
|
|
vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req,
|
|
u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment,
|
|
vm_paddr_t boundary, vm_memattr_t memattr)
|
|
{
|
|
vm_page_t m, m_tmp, m_ret;
|
|
u_int flags;
|
|
int req_class;
|
|
|
|
KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) &&
|
|
(object != NULL || (req & VM_ALLOC_SBUSY) == 0) &&
|
|
((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) !=
|
|
(VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)),
|
|
("vm_page_alloc: inconsistent object(%p)/req(%x)", (void *)object,
|
|
req));
|
|
if (object != NULL) {
|
|
VM_OBJECT_ASSERT_WLOCKED(object);
|
|
KASSERT(object->type == OBJT_PHYS,
|
|
("vm_page_alloc_contig: object %p isn't OBJT_PHYS",
|
|
object));
|
|
}
|
|
KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero"));
|
|
req_class = req & VM_ALLOC_CLASS_MASK;
|
|
|
|
/*
|
|
* The page daemon is allowed to dig deeper into the free page list.
|
|
*/
|
|
if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT)
|
|
req_class = VM_ALLOC_SYSTEM;
|
|
|
|
mtx_lock(&vm_page_queue_free_mtx);
|
|
if (vm_cnt.v_free_count >= npages + vm_cnt.v_free_reserved ||
|
|
(req_class == VM_ALLOC_SYSTEM &&
|
|
vm_cnt.v_free_count >= npages + vm_cnt.v_interrupt_free_min) ||
|
|
(req_class == VM_ALLOC_INTERRUPT &&
|
|
vm_cnt.v_free_count >= npages)) {
|
|
#if VM_NRESERVLEVEL > 0
|
|
retry:
|
|
if (object == NULL || (object->flags & OBJ_COLORED) == 0 ||
|
|
(m_ret = vm_reserv_alloc_contig(object, pindex, npages,
|
|
low, high, alignment, boundary)) == NULL)
|
|
#endif
|
|
m_ret = vm_phys_alloc_contig(npages, low, high,
|
|
alignment, boundary);
|
|
} else {
|
|
mtx_unlock(&vm_page_queue_free_mtx);
|
|
atomic_add_int(&vm_pageout_deficit, npages);
|
|
pagedaemon_wakeup();
|
|
return (NULL);
|
|
}
|
|
if (m_ret != NULL)
|
|
vm_phys_freecnt_adj(m_ret, -npages);
|
|
else {
|
|
#if VM_NRESERVLEVEL > 0
|
|
if (vm_reserv_reclaim_contig(npages, low, high, alignment,
|
|
boundary))
|
|
goto retry;
|
|
#endif
|
|
}
|
|
mtx_unlock(&vm_page_queue_free_mtx);
|
|
if (m_ret == NULL)
|
|
return (NULL);
|
|
for (m = m_ret; m < &m_ret[npages]; m++)
|
|
vm_page_alloc_check(m);
|
|
|
|
/*
|
|
* Initialize the pages. Only the PG_ZERO flag is inherited.
|
|
*/
|
|
flags = 0;
|
|
if ((req & VM_ALLOC_ZERO) != 0)
|
|
flags = PG_ZERO;
|
|
if ((req & VM_ALLOC_NODUMP) != 0)
|
|
flags |= PG_NODUMP;
|
|
if ((req & VM_ALLOC_WIRED) != 0)
|
|
atomic_add_int(&vm_cnt.v_wire_count, npages);
|
|
if (object != NULL) {
|
|
if (object->memattr != VM_MEMATTR_DEFAULT &&
|
|
memattr == VM_MEMATTR_DEFAULT)
|
|
memattr = object->memattr;
|
|
}
|
|
for (m = m_ret; m < &m_ret[npages]; m++) {
|
|
m->aflags = 0;
|
|
m->flags = (m->flags | PG_NODUMP) & flags;
|
|
m->busy_lock = VPB_UNBUSIED;
|
|
if (object != NULL) {
|
|
if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0)
|
|
m->busy_lock = VPB_SINGLE_EXCLUSIVER;
|
|
if ((req & VM_ALLOC_SBUSY) != 0)
|
|
m->busy_lock = VPB_SHARERS_WORD(1);
|
|
}
|
|
if ((req & VM_ALLOC_WIRED) != 0)
|
|
m->wire_count = 1;
|
|
/* Unmanaged pages don't use "act_count". */
|
|
m->oflags = VPO_UNMANAGED;
|
|
if (object != NULL) {
|
|
if (vm_page_insert(m, object, pindex)) {
|
|
if (vm_paging_needed())
|
|
pagedaemon_wakeup();
|
|
if ((req & VM_ALLOC_WIRED) != 0)
|
|
atomic_subtract_int(&vm_cnt.v_wire_count,
|
|
npages);
|
|
for (m_tmp = m, m = m_ret;
|
|
m < &m_ret[npages]; m++) {
|
|
if ((req & VM_ALLOC_WIRED) != 0)
|
|
m->wire_count = 0;
|
|
if (m >= m_tmp) {
|
|
m->object = NULL;
|
|
m->oflags |= VPO_UNMANAGED;
|
|
}
|
|
m->busy_lock = VPB_UNBUSIED;
|
|
vm_page_free(m);
|
|
}
|
|
return (NULL);
|
|
}
|
|
} else
|
|
m->pindex = pindex;
|
|
if (memattr != VM_MEMATTR_DEFAULT)
|
|
pmap_page_set_memattr(m, memattr);
|
|
pindex++;
|
|
}
|
|
if (vm_paging_needed())
|
|
pagedaemon_wakeup();
|
|
return (m_ret);
|
|
}
|
|
|
|
/*
|
|
* Check a page that has been freshly dequeued from a freelist.
|
|
*/
|
|
static void
|
|
vm_page_alloc_check(vm_page_t m)
|
|
{
|
|
|
|
KASSERT(m->queue == PQ_NONE,
|
|
("page %p has unexpected queue %d", m, m->queue));
|
|
KASSERT(m->wire_count == 0, ("page %p is wired", m));
|
|
KASSERT(m->hold_count == 0, ("page %p is held", m));
|
|
KASSERT(!vm_page_busied(m), ("page %p is busy", m));
|
|
KASSERT(m->dirty == 0, ("page %p is dirty", m));
|
|
KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT,
|
|
("page %p has unexpected memattr %d",
|
|
m, pmap_page_get_memattr(m)));
|
|
KASSERT(m->valid == 0, ("free page %p is valid", m));
|
|
}
|
|
|
|
/*
|
|
* vm_page_alloc_freelist:
|
|
*
|
|
* Allocate a physical page from the specified free page list.
|
|
*
|
|
* The caller must always specify an allocation class.
|
|
*
|
|
* allocation classes:
|
|
* VM_ALLOC_NORMAL normal process request
|
|
* VM_ALLOC_SYSTEM system *really* needs a page
|
|
* VM_ALLOC_INTERRUPT interrupt time request
|
|
*
|
|
* optional allocation flags:
|
|
* VM_ALLOC_COUNT(number) the number of additional pages that the caller
|
|
* intends to allocate
|
|
* VM_ALLOC_WIRED wire the allocated page
|
|
* VM_ALLOC_ZERO prefer a zeroed page
|
|
*
|
|
* This routine may not sleep.
|
|
*/
|
|
vm_page_t
|
|
vm_page_alloc_freelist(int flind, int req)
|
|
{
|
|
vm_page_t m;
|
|
u_int flags;
|
|
int req_class;
|
|
|
|
req_class = req & VM_ALLOC_CLASS_MASK;
|
|
|
|
/*
|
|
* The page daemon is allowed to dig deeper into the free page list.
|
|
*/
|
|
if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT)
|
|
req_class = VM_ALLOC_SYSTEM;
|
|
|
|
/*
|
|
* Do not allocate reserved pages unless the req has asked for it.
|
|
*/
|
|
mtx_lock_flags(&vm_page_queue_free_mtx, MTX_RECURSE);
|
|
if (vm_cnt.v_free_count > vm_cnt.v_free_reserved ||
|
|
(req_class == VM_ALLOC_SYSTEM &&
|
|
vm_cnt.v_free_count > vm_cnt.v_interrupt_free_min) ||
|
|
(req_class == VM_ALLOC_INTERRUPT &&
|
|
vm_cnt.v_free_count > 0))
|
|
m = vm_phys_alloc_freelist_pages(flind, VM_FREEPOOL_DIRECT, 0);
|
|
else {
|
|
mtx_unlock(&vm_page_queue_free_mtx);
|
|
atomic_add_int(&vm_pageout_deficit,
|
|
max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1));
|
|
pagedaemon_wakeup();
|
|
return (NULL);
|
|
}
|
|
if (m == NULL) {
|
|
mtx_unlock(&vm_page_queue_free_mtx);
|
|
return (NULL);
|
|
}
|
|
vm_phys_freecnt_adj(m, -1);
|
|
mtx_unlock(&vm_page_queue_free_mtx);
|
|
vm_page_alloc_check(m);
|
|
|
|
/*
|
|
* Initialize the page. Only the PG_ZERO flag is inherited.
|
|
*/
|
|
m->aflags = 0;
|
|
flags = 0;
|
|
if ((req & VM_ALLOC_ZERO) != 0)
|
|
flags = PG_ZERO;
|
|
m->flags &= flags;
|
|
if ((req & VM_ALLOC_WIRED) != 0) {
|
|
/*
|
|
* The page lock is not required for wiring a page that does
|
|
* not belong to an object.
|
|
*/
|
|
atomic_add_int(&vm_cnt.v_wire_count, 1);
|
|
m->wire_count = 1;
|
|
}
|
|
/* Unmanaged pages don't use "act_count". */
|
|
m->oflags = VPO_UNMANAGED;
|
|
if (vm_paging_needed())
|
|
pagedaemon_wakeup();
|
|
return (m);
|
|
}
|
|
|
|
#define VPSC_ANY 0 /* No restrictions. */
|
|
#define VPSC_NORESERV 1 /* Skip reservations; implies VPSC_NOSUPER. */
|
|
#define VPSC_NOSUPER 2 /* Skip superpages. */
|
|
|
|
/*
|
|
* vm_page_scan_contig:
|
|
*
|
|
* Scan vm_page_array[] between the specified entries "m_start" and
|
|
* "m_end" for a run of contiguous physical pages that satisfy the
|
|
* specified conditions, and return the lowest page in the run. The
|
|
* specified "alignment" determines the alignment of the lowest physical
|
|
* page in the run. If the specified "boundary" is non-zero, then the
|
|
* run of physical pages cannot span a physical address that is a
|
|
* multiple of "boundary".
|
|
*
|
|
* "m_end" is never dereferenced, so it need not point to a vm_page
|
|
* structure within vm_page_array[].
|
|
*
|
|
* "npages" must be greater than zero. "m_start" and "m_end" must not
|
|
* span a hole (or discontiguity) in the physical address space. Both
|
|
* "alignment" and "boundary" must be a power of two.
|
|
*/
|
|
vm_page_t
|
|
vm_page_scan_contig(u_long npages, vm_page_t m_start, vm_page_t m_end,
|
|
u_long alignment, vm_paddr_t boundary, int options)
|
|
{
|
|
struct mtx *m_mtx, *new_mtx;
|
|
vm_object_t object;
|
|
vm_paddr_t pa;
|
|
vm_page_t m, m_run;
|
|
#if VM_NRESERVLEVEL > 0
|
|
int level;
|
|
#endif
|
|
int m_inc, order, run_ext, run_len;
|
|
|
|
KASSERT(npages > 0, ("npages is 0"));
|
|
KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
|
|
KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
|
|
m_run = NULL;
|
|
run_len = 0;
|
|
m_mtx = NULL;
|
|
for (m = m_start; m < m_end && run_len < npages; m += m_inc) {
|
|
KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0,
|
|
("page %p is PG_FICTITIOUS or PG_MARKER", m));
|
|
|
|
/*
|
|
* If the current page would be the start of a run, check its
|
|
* physical address against the end, alignment, and boundary
|
|
* conditions. If it doesn't satisfy these conditions, either
|
|
* terminate the scan or advance to the next page that
|
|
* satisfies the failed condition.
|
|
*/
|
|
if (run_len == 0) {
|
|
KASSERT(m_run == NULL, ("m_run != NULL"));
|
|
if (m + npages > m_end)
|
|
break;
|
|
pa = VM_PAGE_TO_PHYS(m);
|
|
if ((pa & (alignment - 1)) != 0) {
|
|
m_inc = atop(roundup2(pa, alignment) - pa);
|
|
continue;
|
|
}
|
|
if (rounddown2(pa ^ (pa + ptoa(npages) - 1),
|
|
boundary) != 0) {
|
|
m_inc = atop(roundup2(pa, boundary) - pa);
|
|
continue;
|
|
}
|
|
} else
|
|
KASSERT(m_run != NULL, ("m_run == NULL"));
|
|
|
|
/*
|
|
* Avoid releasing and reacquiring the same page lock.
|
|
*/
|
|
new_mtx = vm_page_lockptr(m);
|
|
if (m_mtx != new_mtx) {
|
|
if (m_mtx != NULL)
|
|
mtx_unlock(m_mtx);
|
|
m_mtx = new_mtx;
|
|
mtx_lock(m_mtx);
|
|
}
|
|
m_inc = 1;
|
|
retry:
|
|
if (m->wire_count != 0 || m->hold_count != 0)
|
|
run_ext = 0;
|
|
#if VM_NRESERVLEVEL > 0
|
|
else if ((level = vm_reserv_level(m)) >= 0 &&
|
|
(options & VPSC_NORESERV) != 0) {
|
|
run_ext = 0;
|
|
/* Advance to the end of the reservation. */
|
|
pa = VM_PAGE_TO_PHYS(m);
|
|
m_inc = atop(roundup2(pa + 1, vm_reserv_size(level)) -
|
|
pa);
|
|
}
|
|
#endif
|
|
else if ((object = m->object) != NULL) {
|
|
/*
|
|
* The page is considered eligible for relocation if
|
|
* and only if it could be laundered or reclaimed by
|
|
* the page daemon.
|
|
*/
|
|
if (!VM_OBJECT_TRYRLOCK(object)) {
|
|
mtx_unlock(m_mtx);
|
|
VM_OBJECT_RLOCK(object);
|
|
mtx_lock(m_mtx);
|
|
if (m->object != object) {
|
|
/*
|
|
* The page may have been freed.
|
|
*/
|
|
VM_OBJECT_RUNLOCK(object);
|
|
goto retry;
|
|
} else if (m->wire_count != 0 ||
|
|
m->hold_count != 0) {
|
|
run_ext = 0;
|
|
goto unlock;
|
|
}
|
|
}
|
|
KASSERT((m->flags & PG_UNHOLDFREE) == 0,
|
|
("page %p is PG_UNHOLDFREE", m));
|
|
/* Don't care: PG_NODUMP, PG_ZERO. */
|
|
if (object->type != OBJT_DEFAULT &&
|
|
object->type != OBJT_SWAP &&
|
|
object->type != OBJT_VNODE) {
|
|
run_ext = 0;
|
|
#if VM_NRESERVLEVEL > 0
|
|
} else if ((options & VPSC_NOSUPER) != 0 &&
|
|
(level = vm_reserv_level_iffullpop(m)) >= 0) {
|
|
run_ext = 0;
|
|
/* Advance to the end of the superpage. */
|
|
pa = VM_PAGE_TO_PHYS(m);
|
|
m_inc = atop(roundup2(pa + 1,
|
|
vm_reserv_size(level)) - pa);
|
|
#endif
|
|
} else if (object->memattr == VM_MEMATTR_DEFAULT &&
|
|
m->queue != PQ_NONE && !vm_page_busied(m)) {
|
|
/*
|
|
* The page is allocated but eligible for
|
|
* relocation. Extend the current run by one
|
|
* page.
|
|
*/
|
|
KASSERT(pmap_page_get_memattr(m) ==
|
|
VM_MEMATTR_DEFAULT,
|
|
("page %p has an unexpected memattr", m));
|
|
KASSERT((m->oflags & (VPO_SWAPINPROG |
|
|
VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0,
|
|
("page %p has unexpected oflags", m));
|
|
/* Don't care: VPO_NOSYNC. */
|
|
run_ext = 1;
|
|
} else
|
|
run_ext = 0;
|
|
unlock:
|
|
VM_OBJECT_RUNLOCK(object);
|
|
#if VM_NRESERVLEVEL > 0
|
|
} else if (level >= 0) {
|
|
/*
|
|
* The page is reserved but not yet allocated. In
|
|
* other words, it is still cached or free. Extend
|
|
* the current run by one page.
|
|
*/
|
|
run_ext = 1;
|
|
#endif
|
|
} else if ((order = m->order) < VM_NFREEORDER) {
|
|
/*
|
|
* The page is enqueued in the physical memory
|
|
* allocator's cache/free page queues. Moreover, it
|
|
* is the first page in a power-of-two-sized run of
|
|
* contiguous cache/free pages. Add these pages to
|
|
* the end of the current run, and jump ahead.
|
|
*/
|
|
run_ext = 1 << order;
|
|
m_inc = 1 << order;
|
|
} else {
|
|
/*
|
|
* Skip the page for one of the following reasons: (1)
|
|
* It is enqueued in the physical memory allocator's
|
|
* cache/free page queues. However, it is not the
|
|
* first page in a run of contiguous cache/free pages.
|
|
* (This case rarely occurs because the scan is
|
|
* performed in ascending order.) (2) It is not
|
|
* reserved, and it is transitioning from free to
|
|
* allocated. (Conversely, the transition from
|
|
* allocated to free for managed pages is blocked by
|
|
* the page lock.) (3) It is allocated but not
|
|
* contained by an object and not wired, e.g.,
|
|
* allocated by Xen's balloon driver.
|
|
*/
|
|
run_ext = 0;
|
|
}
|
|
|
|
/*
|
|
* Extend or reset the current run of pages.
|
|
*/
|
|
if (run_ext > 0) {
|
|
if (run_len == 0)
|
|
m_run = m;
|
|
run_len += run_ext;
|
|
} else {
|
|
if (run_len > 0) {
|
|
m_run = NULL;
|
|
run_len = 0;
|
|
}
|
|
}
|
|
}
|
|
if (m_mtx != NULL)
|
|
mtx_unlock(m_mtx);
|
|
if (run_len >= npages)
|
|
return (m_run);
|
|
return (NULL);
|
|
}
|
|
|
|
/*
|
|
* vm_page_reclaim_run:
|
|
*
|
|
* Try to relocate each of the allocated virtual pages within the
|
|
* specified run of physical pages to a new physical address. Free the
|
|
* physical pages underlying the relocated virtual pages. A virtual page
|
|
* is relocatable if and only if it could be laundered or reclaimed by
|
|
* the page daemon. Whenever possible, a virtual page is relocated to a
|
|
* physical address above "high".
|
|
*
|
|
* Returns 0 if every physical page within the run was already free or
|
|
* just freed by a successful relocation. Otherwise, returns a non-zero
|
|
* value indicating why the last attempt to relocate a virtual page was
|
|
* unsuccessful.
|
|
*
|
|
* "req_class" must be an allocation class.
|
|
*/
|
|
static int
|
|
vm_page_reclaim_run(int req_class, u_long npages, vm_page_t m_run,
|
|
vm_paddr_t high)
|
|
{
|
|
struct mtx *m_mtx, *new_mtx;
|
|
struct spglist free;
|
|
vm_object_t object;
|
|
vm_paddr_t pa;
|
|
vm_page_t m, m_end, m_new;
|
|
int error, order, req;
|
|
|
|
KASSERT((req_class & VM_ALLOC_CLASS_MASK) == req_class,
|
|
("req_class is not an allocation class"));
|
|
SLIST_INIT(&free);
|
|
error = 0;
|
|
m = m_run;
|
|
m_end = m_run + npages;
|
|
m_mtx = NULL;
|
|
for (; error == 0 && m < m_end; m++) {
|
|
KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0,
|
|
("page %p is PG_FICTITIOUS or PG_MARKER", m));
|
|
|
|
/*
|
|
* Avoid releasing and reacquiring the same page lock.
|
|
*/
|
|
new_mtx = vm_page_lockptr(m);
|
|
if (m_mtx != new_mtx) {
|
|
if (m_mtx != NULL)
|
|
mtx_unlock(m_mtx);
|
|
m_mtx = new_mtx;
|
|
mtx_lock(m_mtx);
|
|
}
|
|
retry:
|
|
if (m->wire_count != 0 || m->hold_count != 0)
|
|
error = EBUSY;
|
|
else if ((object = m->object) != NULL) {
|
|
/*
|
|
* The page is relocated if and only if it could be
|
|
* laundered or reclaimed by the page daemon.
|
|
*/
|
|
if (!VM_OBJECT_TRYWLOCK(object)) {
|
|
mtx_unlock(m_mtx);
|
|
VM_OBJECT_WLOCK(object);
|
|
mtx_lock(m_mtx);
|
|
if (m->object != object) {
|
|
/*
|
|
* The page may have been freed.
|
|
*/
|
|
VM_OBJECT_WUNLOCK(object);
|
|
goto retry;
|
|
} else if (m->wire_count != 0 ||
|
|
m->hold_count != 0) {
|
|
error = EBUSY;
|
|
goto unlock;
|
|
}
|
|
}
|
|
KASSERT((m->flags & PG_UNHOLDFREE) == 0,
|
|
("page %p is PG_UNHOLDFREE", m));
|
|
/* Don't care: PG_NODUMP, PG_ZERO. */
|
|
if (object->type != OBJT_DEFAULT &&
|
|
object->type != OBJT_SWAP &&
|
|
object->type != OBJT_VNODE)
|
|
error = EINVAL;
|
|
else if (object->memattr != VM_MEMATTR_DEFAULT)
|
|
error = EINVAL;
|
|
else if (m->queue != PQ_NONE && !vm_page_busied(m)) {
|
|
KASSERT(pmap_page_get_memattr(m) ==
|
|
VM_MEMATTR_DEFAULT,
|
|
("page %p has an unexpected memattr", m));
|
|
KASSERT((m->oflags & (VPO_SWAPINPROG |
|
|
VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0,
|
|
("page %p has unexpected oflags", m));
|
|
/* Don't care: VPO_NOSYNC. */
|
|
if (m->valid != 0) {
|
|
/*
|
|
* First, try to allocate a new page
|
|
* that is above "high". Failing
|
|
* that, try to allocate a new page
|
|
* that is below "m_run". Allocate
|
|
* the new page between the end of
|
|
* "m_run" and "high" only as a last
|
|
* resort.
|
|
*/
|
|
req = req_class | VM_ALLOC_NOOBJ;
|
|
if ((m->flags & PG_NODUMP) != 0)
|
|
req |= VM_ALLOC_NODUMP;
|
|
if (trunc_page(high) !=
|
|
~(vm_paddr_t)PAGE_MASK) {
|
|
m_new = vm_page_alloc_contig(
|
|
NULL, 0, req, 1,
|
|
round_page(high),
|
|
~(vm_paddr_t)0,
|
|
PAGE_SIZE, 0,
|
|
VM_MEMATTR_DEFAULT);
|
|
} else
|
|
m_new = NULL;
|
|
if (m_new == NULL) {
|
|
pa = VM_PAGE_TO_PHYS(m_run);
|
|
m_new = vm_page_alloc_contig(
|
|
NULL, 0, req, 1,
|
|
0, pa - 1, PAGE_SIZE, 0,
|
|
VM_MEMATTR_DEFAULT);
|
|
}
|
|
if (m_new == NULL) {
|
|
pa += ptoa(npages);
|
|
m_new = vm_page_alloc_contig(
|
|
NULL, 0, req, 1,
|
|
pa, high, PAGE_SIZE, 0,
|
|
VM_MEMATTR_DEFAULT);
|
|
}
|
|
if (m_new == NULL) {
|
|
error = ENOMEM;
|
|
goto unlock;
|
|
}
|
|
KASSERT(m_new->wire_count == 0,
|
|
("page %p is wired", m));
|
|
|
|
/*
|
|
* Replace "m" with the new page. For
|
|
* vm_page_replace(), "m" must be busy
|
|
* and dequeued. Finally, change "m"
|
|
* as if vm_page_free() was called.
|
|
*/
|
|
if (object->ref_count != 0)
|
|
pmap_remove_all(m);
|
|
m_new->aflags = m->aflags;
|
|
KASSERT(m_new->oflags == VPO_UNMANAGED,
|
|
("page %p is managed", m));
|
|
m_new->oflags = m->oflags & VPO_NOSYNC;
|
|
pmap_copy_page(m, m_new);
|
|
m_new->valid = m->valid;
|
|
m_new->dirty = m->dirty;
|
|
m->flags &= ~PG_ZERO;
|
|
vm_page_xbusy(m);
|
|
vm_page_remque(m);
|
|
vm_page_replace_checked(m_new, object,
|
|
m->pindex, m);
|
|
m->valid = 0;
|
|
vm_page_undirty(m);
|
|
|
|
/*
|
|
* The new page must be deactivated
|
|
* before the object is unlocked.
|
|
*/
|
|
new_mtx = vm_page_lockptr(m_new);
|
|
if (m_mtx != new_mtx) {
|
|
mtx_unlock(m_mtx);
|
|
m_mtx = new_mtx;
|
|
mtx_lock(m_mtx);
|
|
}
|
|
vm_page_deactivate(m_new);
|
|
} else {
|
|
m->flags &= ~PG_ZERO;
|
|
vm_page_remque(m);
|
|
vm_page_remove(m);
|
|
KASSERT(m->dirty == 0,
|
|
("page %p is dirty", m));
|
|
}
|
|
SLIST_INSERT_HEAD(&free, m, plinks.s.ss);
|
|
} else
|
|
error = EBUSY;
|
|
unlock:
|
|
VM_OBJECT_WUNLOCK(object);
|
|
} else {
|
|
mtx_lock(&vm_page_queue_free_mtx);
|
|
order = m->order;
|
|
if (order < VM_NFREEORDER) {
|
|
/*
|
|
* The page is enqueued in the physical memory
|
|
* allocator's cache/free page queues.
|
|
* Moreover, it is the first page in a power-
|
|
* of-two-sized run of contiguous cache/free
|
|
* pages. Jump ahead to the last page within
|
|
* that run, and continue from there.
|
|
*/
|
|
m += (1 << order) - 1;
|
|
}
|
|
#if VM_NRESERVLEVEL > 0
|
|
else if (vm_reserv_is_page_free(m))
|
|
order = 0;
|
|
#endif
|
|
mtx_unlock(&vm_page_queue_free_mtx);
|
|
if (order == VM_NFREEORDER)
|
|
error = EINVAL;
|
|
}
|
|
}
|
|
if (m_mtx != NULL)
|
|
mtx_unlock(m_mtx);
|
|
if ((m = SLIST_FIRST(&free)) != NULL) {
|
|
mtx_lock(&vm_page_queue_free_mtx);
|
|
do {
|
|
SLIST_REMOVE_HEAD(&free, plinks.s.ss);
|
|
vm_phys_freecnt_adj(m, 1);
|
|
#if VM_NRESERVLEVEL > 0
|
|
if (!vm_reserv_free_page(m))
|
|
#else
|
|
if (true)
|
|
#endif
|
|
vm_phys_free_pages(m, 0);
|
|
} while ((m = SLIST_FIRST(&free)) != NULL);
|
|
vm_page_free_wakeup();
|
|
mtx_unlock(&vm_page_queue_free_mtx);
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
#define NRUNS 16
|
|
|
|
CTASSERT(powerof2(NRUNS));
|
|
|
|
#define RUN_INDEX(count) ((count) & (NRUNS - 1))
|
|
|
|
#define MIN_RECLAIM 8
|
|
|
|
/*
|
|
* vm_page_reclaim_contig:
|
|
*
|
|
* Reclaim allocated, contiguous physical memory satisfying the specified
|
|
* conditions by relocating the virtual pages using that physical memory.
|
|
* Returns true if reclamation is successful and false otherwise. Since
|
|
* relocation requires the allocation of physical pages, reclamation may
|
|
* fail due to a shortage of cache/free pages. When reclamation fails,
|
|
* callers are expected to perform VM_WAIT before retrying a failed
|
|
* allocation operation, e.g., vm_page_alloc_contig().
|
|
*
|
|
* The caller must always specify an allocation class through "req".
|
|
*
|
|
* allocation classes:
|
|
* VM_ALLOC_NORMAL normal process request
|
|
* VM_ALLOC_SYSTEM system *really* needs a page
|
|
* VM_ALLOC_INTERRUPT interrupt time request
|
|
*
|
|
* The optional allocation flags are ignored.
|
|
*
|
|
* "npages" must be greater than zero. Both "alignment" and "boundary"
|
|
* must be a power of two.
|
|
*/
|
|
bool
|
|
vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low, vm_paddr_t high,
|
|
u_long alignment, vm_paddr_t boundary)
|
|
{
|
|
vm_paddr_t curr_low;
|
|
vm_page_t m_run, m_runs[NRUNS];
|
|
u_long count, reclaimed;
|
|
int error, i, options, req_class;
|
|
|
|
KASSERT(npages > 0, ("npages is 0"));
|
|
KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
|
|
KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
|
|
req_class = req & VM_ALLOC_CLASS_MASK;
|
|
|
|
/*
|
|
* The page daemon is allowed to dig deeper into the free page list.
|
|
*/
|
|
if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT)
|
|
req_class = VM_ALLOC_SYSTEM;
|
|
|
|
/*
|
|
* Return if the number of cached and free pages cannot satisfy the
|
|
* requested allocation.
|
|
*/
|
|
count = vm_cnt.v_free_count;
|
|
if (count < npages + vm_cnt.v_free_reserved || (count < npages +
|
|
vm_cnt.v_interrupt_free_min && req_class == VM_ALLOC_SYSTEM) ||
|
|
(count < npages && req_class == VM_ALLOC_INTERRUPT))
|
|
return (false);
|
|
|
|
/*
|
|
* Scan up to three times, relaxing the restrictions ("options") on
|
|
* the reclamation of reservations and superpages each time.
|
|
*/
|
|
for (options = VPSC_NORESERV;;) {
|
|
/*
|
|
* Find the highest runs that satisfy the given constraints
|
|
* and restrictions, and record them in "m_runs".
|
|
*/
|
|
curr_low = low;
|
|
count = 0;
|
|
for (;;) {
|
|
m_run = vm_phys_scan_contig(npages, curr_low, high,
|
|
alignment, boundary, options);
|
|
if (m_run == NULL)
|
|
break;
|
|
curr_low = VM_PAGE_TO_PHYS(m_run) + ptoa(npages);
|
|
m_runs[RUN_INDEX(count)] = m_run;
|
|
count++;
|
|
}
|
|
|
|
/*
|
|
* Reclaim the highest runs in LIFO (descending) order until
|
|
* the number of reclaimed pages, "reclaimed", is at least
|
|
* MIN_RECLAIM. Reset "reclaimed" each time because each
|
|
* reclamation is idempotent, and runs will (likely) recur
|
|
* from one scan to the next as restrictions are relaxed.
|
|
*/
|
|
reclaimed = 0;
|
|
for (i = 0; count > 0 && i < NRUNS; i++) {
|
|
count--;
|
|
m_run = m_runs[RUN_INDEX(count)];
|
|
error = vm_page_reclaim_run(req_class, npages, m_run,
|
|
high);
|
|
if (error == 0) {
|
|
reclaimed += npages;
|
|
if (reclaimed >= MIN_RECLAIM)
|
|
return (true);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Either relax the restrictions on the next scan or return if
|
|
* the last scan had no restrictions.
|
|
*/
|
|
if (options == VPSC_NORESERV)
|
|
options = VPSC_NOSUPER;
|
|
else if (options == VPSC_NOSUPER)
|
|
options = VPSC_ANY;
|
|
else if (options == VPSC_ANY)
|
|
return (reclaimed != 0);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* vm_wait: (also see VM_WAIT macro)
|
|
*
|
|
* Sleep until free pages are available for allocation.
|
|
* - Called in various places before memory allocations.
|
|
*/
|
|
void
|
|
vm_wait(void)
|
|
{
|
|
|
|
mtx_lock(&vm_page_queue_free_mtx);
|
|
if (curproc == pageproc) {
|
|
vm_pageout_pages_needed = 1;
|
|
msleep(&vm_pageout_pages_needed, &vm_page_queue_free_mtx,
|
|
PDROP | PSWP, "VMWait", 0);
|
|
} else {
|
|
if (__predict_false(pageproc == NULL))
|
|
panic("vm_wait in early boot");
|
|
if (!vm_pageout_wanted) {
|
|
vm_pageout_wanted = true;
|
|
wakeup(&vm_pageout_wanted);
|
|
}
|
|
vm_pages_needed = true;
|
|
msleep(&vm_cnt.v_free_count, &vm_page_queue_free_mtx, PDROP | PVM,
|
|
"vmwait", 0);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* vm_waitpfault: (also see VM_WAITPFAULT macro)
|
|
*
|
|
* Sleep until free pages are available for allocation.
|
|
* - Called only in vm_fault so that processes page faulting
|
|
* can be easily tracked.
|
|
* - Sleeps at a lower priority than vm_wait() so that vm_wait()ing
|
|
* processes will be able to grab memory first. Do not change
|
|
* this balance without careful testing first.
|
|
*/
|
|
void
|
|
vm_waitpfault(void)
|
|
{
|
|
|
|
mtx_lock(&vm_page_queue_free_mtx);
|
|
if (!vm_pageout_wanted) {
|
|
vm_pageout_wanted = true;
|
|
wakeup(&vm_pageout_wanted);
|
|
}
|
|
vm_pages_needed = true;
|
|
msleep(&vm_cnt.v_free_count, &vm_page_queue_free_mtx, PDROP | PUSER,
|
|
"pfault", 0);
|
|
}
|
|
|
|
struct vm_pagequeue *
|
|
vm_page_pagequeue(vm_page_t m)
|
|
{
|
|
|
|
if (vm_page_in_laundry(m))
|
|
return (&vm_dom[0].vmd_pagequeues[m->queue]);
|
|
else
|
|
return (&vm_phys_domain(m)->vmd_pagequeues[m->queue]);
|
|
}
|
|
|
|
/*
|
|
* vm_page_dequeue:
|
|
*
|
|
* Remove the given page from its current page queue.
|
|
*
|
|
* The page must be locked.
|
|
*/
|
|
void
|
|
vm_page_dequeue(vm_page_t m)
|
|
{
|
|
struct vm_pagequeue *pq;
|
|
|
|
vm_page_assert_locked(m);
|
|
KASSERT(m->queue < PQ_COUNT, ("vm_page_dequeue: page %p is not queued",
|
|
m));
|
|
pq = vm_page_pagequeue(m);
|
|
vm_pagequeue_lock(pq);
|
|
m->queue = PQ_NONE;
|
|
TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
|
|
vm_pagequeue_cnt_dec(pq);
|
|
vm_pagequeue_unlock(pq);
|
|
}
|
|
|
|
/*
|
|
* vm_page_dequeue_locked:
|
|
*
|
|
* Remove the given page from its current page queue.
|
|
*
|
|
* The page and page queue must be locked.
|
|
*/
|
|
void
|
|
vm_page_dequeue_locked(vm_page_t m)
|
|
{
|
|
struct vm_pagequeue *pq;
|
|
|
|
vm_page_lock_assert(m, MA_OWNED);
|
|
pq = vm_page_pagequeue(m);
|
|
vm_pagequeue_assert_locked(pq);
|
|
m->queue = PQ_NONE;
|
|
TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
|
|
vm_pagequeue_cnt_dec(pq);
|
|
}
|
|
|
|
/*
|
|
* vm_page_enqueue:
|
|
*
|
|
* Add the given page to the specified page queue.
|
|
*
|
|
* The page must be locked.
|
|
*/
|
|
static void
|
|
vm_page_enqueue(uint8_t queue, vm_page_t m)
|
|
{
|
|
struct vm_pagequeue *pq;
|
|
|
|
vm_page_lock_assert(m, MA_OWNED);
|
|
KASSERT(queue < PQ_COUNT,
|
|
("vm_page_enqueue: invalid queue %u request for page %p",
|
|
queue, m));
|
|
if (queue == PQ_LAUNDRY)
|
|
pq = &vm_dom[0].vmd_pagequeues[queue];
|
|
else
|
|
pq = &vm_phys_domain(m)->vmd_pagequeues[queue];
|
|
vm_pagequeue_lock(pq);
|
|
m->queue = queue;
|
|
TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
|
|
vm_pagequeue_cnt_inc(pq);
|
|
vm_pagequeue_unlock(pq);
|
|
}
|
|
|
|
/*
|
|
* vm_page_requeue:
|
|
*
|
|
* Move the given page to the tail of its current page queue.
|
|
*
|
|
* The page must be locked.
|
|
*/
|
|
void
|
|
vm_page_requeue(vm_page_t m)
|
|
{
|
|
struct vm_pagequeue *pq;
|
|
|
|
vm_page_lock_assert(m, MA_OWNED);
|
|
KASSERT(m->queue != PQ_NONE,
|
|
("vm_page_requeue: page %p is not queued", m));
|
|
pq = vm_page_pagequeue(m);
|
|
vm_pagequeue_lock(pq);
|
|
TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
|
|
TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
|
|
vm_pagequeue_unlock(pq);
|
|
}
|
|
|
|
/*
|
|
* vm_page_requeue_locked:
|
|
*
|
|
* Move the given page to the tail of its current page queue.
|
|
*
|
|
* The page queue must be locked.
|
|
*/
|
|
void
|
|
vm_page_requeue_locked(vm_page_t m)
|
|
{
|
|
struct vm_pagequeue *pq;
|
|
|
|
KASSERT(m->queue != PQ_NONE,
|
|
("vm_page_requeue_locked: page %p is not queued", m));
|
|
pq = vm_page_pagequeue(m);
|
|
vm_pagequeue_assert_locked(pq);
|
|
TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
|
|
TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
|
|
}
|
|
|
|
/*
|
|
* vm_page_activate:
|
|
*
|
|
* Put the specified page on the active list (if appropriate).
|
|
* Ensure that act_count is at least ACT_INIT but do not otherwise
|
|
* mess with it.
|
|
*
|
|
* The page must be locked.
|
|
*/
|
|
void
|
|
vm_page_activate(vm_page_t m)
|
|
{
|
|
int queue;
|
|
|
|
vm_page_lock_assert(m, MA_OWNED);
|
|
if ((queue = m->queue) != PQ_ACTIVE) {
|
|
if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) {
|
|
if (m->act_count < ACT_INIT)
|
|
m->act_count = ACT_INIT;
|
|
if (queue != PQ_NONE)
|
|
vm_page_dequeue(m);
|
|
vm_page_enqueue(PQ_ACTIVE, m);
|
|
} else
|
|
KASSERT(queue == PQ_NONE,
|
|
("vm_page_activate: wired page %p is queued", m));
|
|
} else {
|
|
if (m->act_count < ACT_INIT)
|
|
m->act_count = ACT_INIT;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* vm_page_free_wakeup:
|
|
*
|
|
* Helper routine for vm_page_free_toq() and vm_page_cache(). This
|
|
* routine is called when a page has been added to the cache or free
|
|
* queues.
|
|
*
|
|
* The page queues must be locked.
|
|
*/
|
|
static inline void
|
|
vm_page_free_wakeup(void)
|
|
{
|
|
|
|
mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
|
|
/*
|
|
* if pageout daemon needs pages, then tell it that there are
|
|
* some free.
|
|
*/
|
|
if (vm_pageout_pages_needed &&
|
|
vm_cnt.v_free_count >= vm_cnt.v_pageout_free_min) {
|
|
wakeup(&vm_pageout_pages_needed);
|
|
vm_pageout_pages_needed = 0;
|
|
}
|
|
/*
|
|
* wakeup processes that are waiting on memory if we hit a
|
|
* high water mark. And wakeup scheduler process if we have
|
|
* lots of memory. this process will swapin processes.
|
|
*/
|
|
if (vm_pages_needed && !vm_page_count_min()) {
|
|
vm_pages_needed = false;
|
|
wakeup(&vm_cnt.v_free_count);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* vm_page_free_toq:
|
|
*
|
|
* Returns the given page to the free list,
|
|
* disassociating it with any VM object.
|
|
*
|
|
* The object must be locked. The page must be locked if it is managed.
|
|
*/
|
|
void
|
|
vm_page_free_toq(vm_page_t m)
|
|
{
|
|
|
|
if ((m->oflags & VPO_UNMANAGED) == 0) {
|
|
vm_page_lock_assert(m, MA_OWNED);
|
|
KASSERT(!pmap_page_is_mapped(m),
|
|
("vm_page_free_toq: freeing mapped page %p", m));
|
|
} else
|
|
KASSERT(m->queue == PQ_NONE,
|
|
("vm_page_free_toq: unmanaged page %p is queued", m));
|
|
PCPU_INC(cnt.v_tfree);
|
|
|
|
if (vm_page_sbusied(m))
|
|
panic("vm_page_free: freeing busy page %p", m);
|
|
|
|
/*
|
|
* Unqueue, then remove page. Note that we cannot destroy
|
|
* the page here because we do not want to call the pager's
|
|
* callback routine until after we've put the page on the
|
|
* appropriate free queue.
|
|
*/
|
|
vm_page_remque(m);
|
|
vm_page_remove(m);
|
|
|
|
/*
|
|
* If fictitious remove object association and
|
|
* return, otherwise delay object association removal.
|
|
*/
|
|
if ((m->flags & PG_FICTITIOUS) != 0) {
|
|
return;
|
|
}
|
|
|
|
m->valid = 0;
|
|
vm_page_undirty(m);
|
|
|
|
if (m->wire_count != 0)
|
|
panic("vm_page_free: freeing wired page %p", m);
|
|
if (m->hold_count != 0) {
|
|
m->flags &= ~PG_ZERO;
|
|
KASSERT((m->flags & PG_UNHOLDFREE) == 0,
|
|
("vm_page_free: freeing PG_UNHOLDFREE page %p", m));
|
|
m->flags |= PG_UNHOLDFREE;
|
|
} else {
|
|
/*
|
|
* Restore the default memory attribute to the page.
|
|
*/
|
|
if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT)
|
|
pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT);
|
|
|
|
/*
|
|
* Insert the page into the physical memory allocator's
|
|
* cache/free page queues.
|
|
*/
|
|
mtx_lock(&vm_page_queue_free_mtx);
|
|
vm_phys_freecnt_adj(m, 1);
|
|
#if VM_NRESERVLEVEL > 0
|
|
if (!vm_reserv_free_page(m))
|
|
#else
|
|
if (TRUE)
|
|
#endif
|
|
vm_phys_free_pages(m, 0);
|
|
vm_page_free_wakeup();
|
|
mtx_unlock(&vm_page_queue_free_mtx);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* vm_page_wire:
|
|
*
|
|
* Mark this page as wired down by yet
|
|
* another map, removing it from paging queues
|
|
* as necessary.
|
|
*
|
|
* If the page is fictitious, then its wire count must remain one.
|
|
*
|
|
* The page must be locked.
|
|
*/
|
|
void
|
|
vm_page_wire(vm_page_t m)
|
|
{
|
|
|
|
/*
|
|
* Only bump the wire statistics if the page is not already wired,
|
|
* and only unqueue the page if it is on some queue (if it is unmanaged
|
|
* it is already off the queues).
|
|
*/
|
|
vm_page_lock_assert(m, MA_OWNED);
|
|
if ((m->flags & PG_FICTITIOUS) != 0) {
|
|
KASSERT(m->wire_count == 1,
|
|
("vm_page_wire: fictitious page %p's wire count isn't one",
|
|
m));
|
|
return;
|
|
}
|
|
if (m->wire_count == 0) {
|
|
KASSERT((m->oflags & VPO_UNMANAGED) == 0 ||
|
|
m->queue == PQ_NONE,
|
|
("vm_page_wire: unmanaged page %p is queued", m));
|
|
vm_page_remque(m);
|
|
atomic_add_int(&vm_cnt.v_wire_count, 1);
|
|
}
|
|
m->wire_count++;
|
|
KASSERT(m->wire_count != 0, ("vm_page_wire: wire_count overflow m=%p", m));
|
|
}
|
|
|
|
/*
|
|
* vm_page_unwire:
|
|
*
|
|
* Release one wiring of the specified page, potentially allowing it to be
|
|
* paged out. Returns TRUE if the number of wirings transitions to zero and
|
|
* FALSE otherwise.
|
|
*
|
|
* Only managed pages belonging to an object can be paged out. If the number
|
|
* of wirings transitions to zero and the page is eligible for page out, then
|
|
* the page is added to the specified paging queue (unless PQ_NONE is
|
|
* specified).
|
|
*
|
|
* If a page is fictitious, then its wire count must always be one.
|
|
*
|
|
* A managed page must be locked.
|
|
*/
|
|
boolean_t
|
|
vm_page_unwire(vm_page_t m, uint8_t queue)
|
|
{
|
|
|
|
KASSERT(queue < PQ_COUNT || queue == PQ_NONE,
|
|
("vm_page_unwire: invalid queue %u request for page %p",
|
|
queue, m));
|
|
if ((m->oflags & VPO_UNMANAGED) == 0)
|
|
vm_page_assert_locked(m);
|
|
if ((m->flags & PG_FICTITIOUS) != 0) {
|
|
KASSERT(m->wire_count == 1,
|
|
("vm_page_unwire: fictitious page %p's wire count isn't one", m));
|
|
return (FALSE);
|
|
}
|
|
if (m->wire_count > 0) {
|
|
m->wire_count--;
|
|
if (m->wire_count == 0) {
|
|
atomic_subtract_int(&vm_cnt.v_wire_count, 1);
|
|
if ((m->oflags & VPO_UNMANAGED) == 0 &&
|
|
m->object != NULL && queue != PQ_NONE)
|
|
vm_page_enqueue(queue, m);
|
|
return (TRUE);
|
|
} else
|
|
return (FALSE);
|
|
} else
|
|
panic("vm_page_unwire: page %p's wire count is zero", m);
|
|
}
|
|
|
|
/*
|
|
* Move the specified page to the inactive queue.
|
|
*
|
|
* Many pages placed on the inactive queue should actually go
|
|
* into the cache, but it is difficult to figure out which. What
|
|
* we do instead, if the inactive target is well met, is to put
|
|
* clean pages at the head of the inactive queue instead of the tail.
|
|
* This will cause them to be moved to the cache more quickly and
|
|
* if not actively re-referenced, reclaimed more quickly. If we just
|
|
* stick these pages at the end of the inactive queue, heavy filesystem
|
|
* meta-data accesses can cause an unnecessary paging load on memory bound
|
|
* processes. This optimization causes one-time-use metadata to be
|
|
* reused more quickly.
|
|
*
|
|
* Normally noreuse is FALSE, resulting in LRU operation. noreuse is set
|
|
* to TRUE if we want this page to be 'as if it were placed in the cache',
|
|
* except without unmapping it from the process address space. In
|
|
* practice this is implemented by inserting the page at the head of the
|
|
* queue, using a marker page to guide FIFO insertion ordering.
|
|
*
|
|
* The page must be locked.
|
|
*/
|
|
static inline void
|
|
_vm_page_deactivate(vm_page_t m, boolean_t noreuse)
|
|
{
|
|
struct vm_pagequeue *pq;
|
|
int queue;
|
|
|
|
vm_page_assert_locked(m);
|
|
|
|
/*
|
|
* Ignore if the page is already inactive, unless it is unlikely to be
|
|
* reactivated.
|
|
*/
|
|
if ((queue = m->queue) == PQ_INACTIVE && !noreuse)
|
|
return;
|
|
if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) {
|
|
pq = &vm_phys_domain(m)->vmd_pagequeues[PQ_INACTIVE];
|
|
/* Avoid multiple acquisitions of the inactive queue lock. */
|
|
if (queue == PQ_INACTIVE) {
|
|
vm_pagequeue_lock(pq);
|
|
vm_page_dequeue_locked(m);
|
|
} else {
|
|
if (queue != PQ_NONE)
|
|
vm_page_dequeue(m);
|
|
vm_pagequeue_lock(pq);
|
|
}
|
|
m->queue = PQ_INACTIVE;
|
|
if (noreuse)
|
|
TAILQ_INSERT_BEFORE(&vm_phys_domain(m)->vmd_inacthead,
|
|
m, plinks.q);
|
|
else
|
|
TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
|
|
vm_pagequeue_cnt_inc(pq);
|
|
vm_pagequeue_unlock(pq);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Move the specified page to the inactive queue.
|
|
*
|
|
* The page must be locked.
|
|
*/
|
|
void
|
|
vm_page_deactivate(vm_page_t m)
|
|
{
|
|
|
|
_vm_page_deactivate(m, FALSE);
|
|
}
|
|
|
|
/*
|
|
* Move the specified page to the inactive queue with the expectation
|
|
* that it is unlikely to be reused.
|
|
*
|
|
* The page must be locked.
|
|
*/
|
|
void
|
|
vm_page_deactivate_noreuse(vm_page_t m)
|
|
{
|
|
|
|
_vm_page_deactivate(m, TRUE);
|
|
}
|
|
|
|
/*
|
|
* vm_page_launder
|
|
*
|
|
* Put a page in the laundry.
|
|
*/
|
|
void
|
|
vm_page_launder(vm_page_t m)
|
|
{
|
|
int queue;
|
|
|
|
vm_page_assert_locked(m);
|
|
if ((queue = m->queue) != PQ_LAUNDRY) {
|
|
if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) {
|
|
if (queue != PQ_NONE)
|
|
vm_page_dequeue(m);
|
|
vm_page_enqueue(PQ_LAUNDRY, m);
|
|
} else
|
|
KASSERT(queue == PQ_NONE,
|
|
("wired page %p is queued", m));
|
|
}
|
|
}
|
|
|
|
/*
|
|
* vm_page_try_to_free()
|
|
*
|
|
* Attempt to free the page. If we cannot free it, we do nothing.
|
|
* 1 is returned on success, 0 on failure.
|
|
*/
|
|
int
|
|
vm_page_try_to_free(vm_page_t m)
|
|
{
|
|
|
|
vm_page_lock_assert(m, MA_OWNED);
|
|
if (m->object != NULL)
|
|
VM_OBJECT_ASSERT_WLOCKED(m->object);
|
|
if (m->dirty || m->hold_count || m->wire_count ||
|
|
(m->oflags & VPO_UNMANAGED) != 0 || vm_page_busied(m))
|
|
return (0);
|
|
pmap_remove_all(m);
|
|
if (m->dirty)
|
|
return (0);
|
|
vm_page_free(m);
|
|
return (1);
|
|
}
|
|
|
|
/*
|
|
* vm_page_advise
|
|
*
|
|
* Deactivate or do nothing, as appropriate.
|
|
*
|
|
* The object and page must be locked.
|
|
*/
|
|
void
|
|
vm_page_advise(vm_page_t m, int advice)
|
|
{
|
|
|
|
vm_page_assert_locked(m);
|
|
VM_OBJECT_ASSERT_WLOCKED(m->object);
|
|
if (advice == MADV_FREE)
|
|
/*
|
|
* Mark the page clean. This will allow the page to be freed
|
|
* up by the system. However, such pages are often reused
|
|
* quickly by malloc() so we do not do anything that would
|
|
* cause a page fault if we can help it.
|
|
*
|
|
* Specifically, we do not try to actually free the page now
|
|
* nor do we try to put it in the cache (which would cause a
|
|
* page fault on reuse).
|
|
*
|
|
* But we do make the page as freeable as we can without
|
|
* actually taking the step of unmapping it.
|
|
*/
|
|
vm_page_undirty(m);
|
|
else if (advice != MADV_DONTNEED)
|
|
return;
|
|
|
|
/*
|
|
* Clear any references to the page. Otherwise, the page daemon will
|
|
* immediately reactivate the page.
|
|
*/
|
|
vm_page_aflag_clear(m, PGA_REFERENCED);
|
|
|
|
if (advice != MADV_FREE && m->dirty == 0 && pmap_is_modified(m))
|
|
vm_page_dirty(m);
|
|
|
|
/*
|
|
* Place clean pages near the head of the inactive queue rather than
|
|
* the tail, thus defeating the queue's LRU operation and ensuring that
|
|
* the page will be reused quickly. Dirty pages not already in the
|
|
* laundry are moved there.
|
|
*/
|
|
if (m->dirty == 0)
|
|
vm_page_deactivate_noreuse(m);
|
|
else
|
|
vm_page_launder(m);
|
|
}
|
|
|
|
/*
|
|
* Grab a page, waiting until we are waken up due to the page
|
|
* changing state. We keep on waiting, if the page continues
|
|
* to be in the object. If the page doesn't exist, first allocate it
|
|
* and then conditionally zero it.
|
|
*
|
|
* This routine may sleep.
|
|
*
|
|
* The object must be locked on entry. The lock will, however, be released
|
|
* and reacquired if the routine sleeps.
|
|
*/
|
|
vm_page_t
|
|
vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags)
|
|
{
|
|
vm_page_t m;
|
|
int sleep;
|
|
|
|
VM_OBJECT_ASSERT_WLOCKED(object);
|
|
KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 ||
|
|
(allocflags & VM_ALLOC_IGN_SBUSY) != 0,
|
|
("vm_page_grab: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch"));
|
|
retrylookup:
|
|
if ((m = vm_page_lookup(object, pindex)) != NULL) {
|
|
sleep = (allocflags & VM_ALLOC_IGN_SBUSY) != 0 ?
|
|
vm_page_xbusied(m) : vm_page_busied(m);
|
|
if (sleep) {
|
|
if ((allocflags & VM_ALLOC_NOWAIT) != 0)
|
|
return (NULL);
|
|
/*
|
|
* Reference the page before unlocking and
|
|
* sleeping so that the page daemon is less
|
|
* likely to reclaim it.
|
|
*/
|
|
vm_page_aflag_set(m, PGA_REFERENCED);
|
|
vm_page_lock(m);
|
|
VM_OBJECT_WUNLOCK(object);
|
|
vm_page_busy_sleep(m, "pgrbwt", (allocflags &
|
|
VM_ALLOC_IGN_SBUSY) != 0);
|
|
VM_OBJECT_WLOCK(object);
|
|
goto retrylookup;
|
|
} else {
|
|
if ((allocflags & VM_ALLOC_WIRED) != 0) {
|
|
vm_page_lock(m);
|
|
vm_page_wire(m);
|
|
vm_page_unlock(m);
|
|
}
|
|
if ((allocflags &
|
|
(VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0)
|
|
vm_page_xbusy(m);
|
|
if ((allocflags & VM_ALLOC_SBUSY) != 0)
|
|
vm_page_sbusy(m);
|
|
return (m);
|
|
}
|
|
}
|
|
m = vm_page_alloc(object, pindex, allocflags);
|
|
if (m == NULL) {
|
|
if ((allocflags & VM_ALLOC_NOWAIT) != 0)
|
|
return (NULL);
|
|
VM_OBJECT_WUNLOCK(object);
|
|
VM_WAIT;
|
|
VM_OBJECT_WLOCK(object);
|
|
goto retrylookup;
|
|
}
|
|
if (allocflags & VM_ALLOC_ZERO && (m->flags & PG_ZERO) == 0)
|
|
pmap_zero_page(m);
|
|
return (m);
|
|
}
|
|
|
|
/*
|
|
* Mapping function for valid or dirty bits in a page.
|
|
*
|
|
* Inputs are required to range within a page.
|
|
*/
|
|
vm_page_bits_t
|
|
vm_page_bits(int base, int size)
|
|
{
|
|
int first_bit;
|
|
int last_bit;
|
|
|
|
KASSERT(
|
|
base + size <= PAGE_SIZE,
|
|
("vm_page_bits: illegal base/size %d/%d", base, size)
|
|
);
|
|
|
|
if (size == 0) /* handle degenerate case */
|
|
return (0);
|
|
|
|
first_bit = base >> DEV_BSHIFT;
|
|
last_bit = (base + size - 1) >> DEV_BSHIFT;
|
|
|
|
return (((vm_page_bits_t)2 << last_bit) -
|
|
((vm_page_bits_t)1 << first_bit));
|
|
}
|
|
|
|
/*
|
|
* vm_page_set_valid_range:
|
|
*
|
|
* Sets portions of a page valid. The arguments are expected
|
|
* to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive
|
|
* of any partial chunks touched by the range. The invalid portion of
|
|
* such chunks will be zeroed.
|
|
*
|
|
* (base + size) must be less then or equal to PAGE_SIZE.
|
|
*/
|
|
void
|
|
vm_page_set_valid_range(vm_page_t m, int base, int size)
|
|
{
|
|
int endoff, frag;
|
|
|
|
VM_OBJECT_ASSERT_WLOCKED(m->object);
|
|
if (size == 0) /* handle degenerate case */
|
|
return;
|
|
|
|
/*
|
|
* If the base is not DEV_BSIZE aligned and the valid
|
|
* bit is clear, we have to zero out a portion of the
|
|
* first block.
|
|
*/
|
|
if ((frag = rounddown2(base, DEV_BSIZE)) != base &&
|
|
(m->valid & (1 << (base >> DEV_BSHIFT))) == 0)
|
|
pmap_zero_page_area(m, frag, base - frag);
|
|
|
|
/*
|
|
* If the ending offset is not DEV_BSIZE aligned and the
|
|
* valid bit is clear, we have to zero out a portion of
|
|
* the last block.
|
|
*/
|
|
endoff = base + size;
|
|
if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff &&
|
|
(m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0)
|
|
pmap_zero_page_area(m, endoff,
|
|
DEV_BSIZE - (endoff & (DEV_BSIZE - 1)));
|
|
|
|
/*
|
|
* Assert that no previously invalid block that is now being validated
|
|
* is already dirty.
|
|
*/
|
|
KASSERT((~m->valid & vm_page_bits(base, size) & m->dirty) == 0,
|
|
("vm_page_set_valid_range: page %p is dirty", m));
|
|
|
|
/*
|
|
* Set valid bits inclusive of any overlap.
|
|
*/
|
|
m->valid |= vm_page_bits(base, size);
|
|
}
|
|
|
|
/*
|
|
* Clear the given bits from the specified page's dirty field.
|
|
*/
|
|
static __inline void
|
|
vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits)
|
|
{
|
|
uintptr_t addr;
|
|
#if PAGE_SIZE < 16384
|
|
int shift;
|
|
#endif
|
|
|
|
/*
|
|
* If the object is locked and the page is neither exclusive busy nor
|
|
* write mapped, then the page's dirty field cannot possibly be
|
|
* set by a concurrent pmap operation.
|
|
*/
|
|
VM_OBJECT_ASSERT_WLOCKED(m->object);
|
|
if (!vm_page_xbusied(m) && !pmap_page_is_write_mapped(m))
|
|
m->dirty &= ~pagebits;
|
|
else {
|
|
/*
|
|
* The pmap layer can call vm_page_dirty() without
|
|
* holding a distinguished lock. The combination of
|
|
* the object's lock and an atomic operation suffice
|
|
* to guarantee consistency of the page dirty field.
|
|
*
|
|
* For PAGE_SIZE == 32768 case, compiler already
|
|
* properly aligns the dirty field, so no forcible
|
|
* alignment is needed. Only require existence of
|
|
* atomic_clear_64 when page size is 32768.
|
|
*/
|
|
addr = (uintptr_t)&m->dirty;
|
|
#if PAGE_SIZE == 32768
|
|
atomic_clear_64((uint64_t *)addr, pagebits);
|
|
#elif PAGE_SIZE == 16384
|
|
atomic_clear_32((uint32_t *)addr, pagebits);
|
|
#else /* PAGE_SIZE <= 8192 */
|
|
/*
|
|
* Use a trick to perform a 32-bit atomic on the
|
|
* containing aligned word, to not depend on the existence
|
|
* of atomic_clear_{8, 16}.
|
|
*/
|
|
shift = addr & (sizeof(uint32_t) - 1);
|
|
#if BYTE_ORDER == BIG_ENDIAN
|
|
shift = (sizeof(uint32_t) - sizeof(m->dirty) - shift) * NBBY;
|
|
#else
|
|
shift *= NBBY;
|
|
#endif
|
|
addr &= ~(sizeof(uint32_t) - 1);
|
|
atomic_clear_32((uint32_t *)addr, pagebits << shift);
|
|
#endif /* PAGE_SIZE */
|
|
}
|
|
}
|
|
|
|
/*
|
|
* vm_page_set_validclean:
|
|
*
|
|
* Sets portions of a page valid and clean. The arguments are expected
|
|
* to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive
|
|
* of any partial chunks touched by the range. The invalid portion of
|
|
* such chunks will be zero'd.
|
|
*
|
|
* (base + size) must be less then or equal to PAGE_SIZE.
|
|
*/
|
|
void
|
|
vm_page_set_validclean(vm_page_t m, int base, int size)
|
|
{
|
|
vm_page_bits_t oldvalid, pagebits;
|
|
int endoff, frag;
|
|
|
|
VM_OBJECT_ASSERT_WLOCKED(m->object);
|
|
if (size == 0) /* handle degenerate case */
|
|
return;
|
|
|
|
/*
|
|
* If the base is not DEV_BSIZE aligned and the valid
|
|
* bit is clear, we have to zero out a portion of the
|
|
* first block.
|
|
*/
|
|
if ((frag = rounddown2(base, DEV_BSIZE)) != base &&
|
|
(m->valid & ((vm_page_bits_t)1 << (base >> DEV_BSHIFT))) == 0)
|
|
pmap_zero_page_area(m, frag, base - frag);
|
|
|
|
/*
|
|
* If the ending offset is not DEV_BSIZE aligned and the
|
|
* valid bit is clear, we have to zero out a portion of
|
|
* the last block.
|
|
*/
|
|
endoff = base + size;
|
|
if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff &&
|
|
(m->valid & ((vm_page_bits_t)1 << (endoff >> DEV_BSHIFT))) == 0)
|
|
pmap_zero_page_area(m, endoff,
|
|
DEV_BSIZE - (endoff & (DEV_BSIZE - 1)));
|
|
|
|
/*
|
|
* Set valid, clear dirty bits. If validating the entire
|
|
* page we can safely clear the pmap modify bit. We also
|
|
* use this opportunity to clear the VPO_NOSYNC flag. If a process
|
|
* takes a write fault on a MAP_NOSYNC memory area the flag will
|
|
* be set again.
|
|
*
|
|
* We set valid bits inclusive of any overlap, but we can only
|
|
* clear dirty bits for DEV_BSIZE chunks that are fully within
|
|
* the range.
|
|
*/
|
|
oldvalid = m->valid;
|
|
pagebits = vm_page_bits(base, size);
|
|
m->valid |= pagebits;
|
|
#if 0 /* NOT YET */
|
|
if ((frag = base & (DEV_BSIZE - 1)) != 0) {
|
|
frag = DEV_BSIZE - frag;
|
|
base += frag;
|
|
size -= frag;
|
|
if (size < 0)
|
|
size = 0;
|
|
}
|
|
pagebits = vm_page_bits(base, size & (DEV_BSIZE - 1));
|
|
#endif
|
|
if (base == 0 && size == PAGE_SIZE) {
|
|
/*
|
|
* The page can only be modified within the pmap if it is
|
|
* mapped, and it can only be mapped if it was previously
|
|
* fully valid.
|
|
*/
|
|
if (oldvalid == VM_PAGE_BITS_ALL)
|
|
/*
|
|
* Perform the pmap_clear_modify() first. Otherwise,
|
|
* a concurrent pmap operation, such as
|
|
* pmap_protect(), could clear a modification in the
|
|
* pmap and set the dirty field on the page before
|
|
* pmap_clear_modify() had begun and after the dirty
|
|
* field was cleared here.
|
|
*/
|
|
pmap_clear_modify(m);
|
|
m->dirty = 0;
|
|
m->oflags &= ~VPO_NOSYNC;
|
|
} else if (oldvalid != VM_PAGE_BITS_ALL)
|
|
m->dirty &= ~pagebits;
|
|
else
|
|
vm_page_clear_dirty_mask(m, pagebits);
|
|
}
|
|
|
|
void
|
|
vm_page_clear_dirty(vm_page_t m, int base, int size)
|
|
{
|
|
|
|
vm_page_clear_dirty_mask(m, vm_page_bits(base, size));
|
|
}
|
|
|
|
/*
|
|
* vm_page_set_invalid:
|
|
*
|
|
* Invalidates DEV_BSIZE'd chunks within a page. Both the
|
|
* valid and dirty bits for the effected areas are cleared.
|
|
*/
|
|
void
|
|
vm_page_set_invalid(vm_page_t m, int base, int size)
|
|
{
|
|
vm_page_bits_t bits;
|
|
vm_object_t object;
|
|
|
|
object = m->object;
|
|
VM_OBJECT_ASSERT_WLOCKED(object);
|
|
if (object->type == OBJT_VNODE && base == 0 && IDX_TO_OFF(m->pindex) +
|
|
size >= object->un_pager.vnp.vnp_size)
|
|
bits = VM_PAGE_BITS_ALL;
|
|
else
|
|
bits = vm_page_bits(base, size);
|
|
if (object->ref_count != 0 && m->valid == VM_PAGE_BITS_ALL &&
|
|
bits != 0)
|
|
pmap_remove_all(m);
|
|
KASSERT((bits == 0 && m->valid == VM_PAGE_BITS_ALL) ||
|
|
!pmap_page_is_mapped(m),
|
|
("vm_page_set_invalid: page %p is mapped", m));
|
|
m->valid &= ~bits;
|
|
m->dirty &= ~bits;
|
|
}
|
|
|
|
/*
|
|
* vm_page_zero_invalid()
|
|
*
|
|
* The kernel assumes that the invalid portions of a page contain
|
|
* garbage, but such pages can be mapped into memory by user code.
|
|
* When this occurs, we must zero out the non-valid portions of the
|
|
* page so user code sees what it expects.
|
|
*
|
|
* Pages are most often semi-valid when the end of a file is mapped
|
|
* into memory and the file's size is not page aligned.
|
|
*/
|
|
void
|
|
vm_page_zero_invalid(vm_page_t m, boolean_t setvalid)
|
|
{
|
|
int b;
|
|
int i;
|
|
|
|
VM_OBJECT_ASSERT_WLOCKED(m->object);
|
|
/*
|
|
* Scan the valid bits looking for invalid sections that
|
|
* must be zeroed. Invalid sub-DEV_BSIZE'd areas ( where the
|
|
* valid bit may be set ) have already been zeroed by
|
|
* vm_page_set_validclean().
|
|
*/
|
|
for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) {
|
|
if (i == (PAGE_SIZE / DEV_BSIZE) ||
|
|
(m->valid & ((vm_page_bits_t)1 << i))) {
|
|
if (i > b) {
|
|
pmap_zero_page_area(m,
|
|
b << DEV_BSHIFT, (i - b) << DEV_BSHIFT);
|
|
}
|
|
b = i + 1;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* setvalid is TRUE when we can safely set the zero'd areas
|
|
* as being valid. We can do this if there are no cache consistancy
|
|
* issues. e.g. it is ok to do with UFS, but not ok to do with NFS.
|
|
*/
|
|
if (setvalid)
|
|
m->valid = VM_PAGE_BITS_ALL;
|
|
}
|
|
|
|
/*
|
|
* vm_page_is_valid:
|
|
*
|
|
* Is (partial) page valid? Note that the case where size == 0
|
|
* will return FALSE in the degenerate case where the page is
|
|
* entirely invalid, and TRUE otherwise.
|
|
*/
|
|
int
|
|
vm_page_is_valid(vm_page_t m, int base, int size)
|
|
{
|
|
vm_page_bits_t bits;
|
|
|
|
VM_OBJECT_ASSERT_LOCKED(m->object);
|
|
bits = vm_page_bits(base, size);
|
|
return (m->valid != 0 && (m->valid & bits) == bits);
|
|
}
|
|
|
|
/*
|
|
* vm_page_ps_is_valid:
|
|
*
|
|
* Returns TRUE if the entire (super)page is valid and FALSE otherwise.
|
|
*/
|
|
boolean_t
|
|
vm_page_ps_is_valid(vm_page_t m)
|
|
{
|
|
int i, npages;
|
|
|
|
VM_OBJECT_ASSERT_LOCKED(m->object);
|
|
npages = atop(pagesizes[m->psind]);
|
|
|
|
/*
|
|
* The physically contiguous pages that make up a superpage, i.e., a
|
|
* page with a page size index ("psind") greater than zero, will
|
|
* occupy adjacent entries in vm_page_array[].
|
|
*/
|
|
for (i = 0; i < npages; i++) {
|
|
if (m[i].valid != VM_PAGE_BITS_ALL)
|
|
return (FALSE);
|
|
}
|
|
return (TRUE);
|
|
}
|
|
|
|
/*
|
|
* Set the page's dirty bits if the page is modified.
|
|
*/
|
|
void
|
|
vm_page_test_dirty(vm_page_t m)
|
|
{
|
|
|
|
VM_OBJECT_ASSERT_WLOCKED(m->object);
|
|
if (m->dirty != VM_PAGE_BITS_ALL && pmap_is_modified(m))
|
|
vm_page_dirty(m);
|
|
}
|
|
|
|
void
|
|
vm_page_lock_KBI(vm_page_t m, const char *file, int line)
|
|
{
|
|
|
|
mtx_lock_flags_(vm_page_lockptr(m), 0, file, line);
|
|
}
|
|
|
|
void
|
|
vm_page_unlock_KBI(vm_page_t m, const char *file, int line)
|
|
{
|
|
|
|
mtx_unlock_flags_(vm_page_lockptr(m), 0, file, line);
|
|
}
|
|
|
|
int
|
|
vm_page_trylock_KBI(vm_page_t m, const char *file, int line)
|
|
{
|
|
|
|
return (mtx_trylock_flags_(vm_page_lockptr(m), 0, file, line));
|
|
}
|
|
|
|
#if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
|
|
void
|
|
vm_page_assert_locked_KBI(vm_page_t m, const char *file, int line)
|
|
{
|
|
|
|
vm_page_lock_assert_KBI(m, MA_OWNED, file, line);
|
|
}
|
|
|
|
void
|
|
vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line)
|
|
{
|
|
|
|
mtx_assert_(vm_page_lockptr(m), a, file, line);
|
|
}
|
|
#endif
|
|
|
|
#ifdef INVARIANTS
|
|
void
|
|
vm_page_object_lock_assert(vm_page_t m)
|
|
{
|
|
|
|
/*
|
|
* Certain of the page's fields may only be modified by the
|
|
* holder of the containing object's lock or the exclusive busy.
|
|
* holder. Unfortunately, the holder of the write busy is
|
|
* not recorded, and thus cannot be checked here.
|
|
*/
|
|
if (m->object != NULL && !vm_page_xbusied(m))
|
|
VM_OBJECT_ASSERT_WLOCKED(m->object);
|
|
}
|
|
|
|
void
|
|
vm_page_assert_pga_writeable(vm_page_t m, uint8_t bits)
|
|
{
|
|
|
|
if ((bits & PGA_WRITEABLE) == 0)
|
|
return;
|
|
|
|
/*
|
|
* The PGA_WRITEABLE flag can only be set if the page is
|
|
* managed, is exclusively busied or the object is locked.
|
|
* Currently, this flag is only set by pmap_enter().
|
|
*/
|
|
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
|
|
("PGA_WRITEABLE on unmanaged page"));
|
|
if (!vm_page_xbusied(m))
|
|
VM_OBJECT_ASSERT_LOCKED(m->object);
|
|
}
|
|
#endif
|
|
|
|
#include "opt_ddb.h"
|
|
#ifdef DDB
|
|
#include <sys/kernel.h>
|
|
|
|
#include <ddb/ddb.h>
|
|
|
|
DB_SHOW_COMMAND(page, vm_page_print_page_info)
|
|
{
|
|
|
|
db_printf("vm_cnt.v_free_count: %d\n", vm_cnt.v_free_count);
|
|
db_printf("vm_cnt.v_inactive_count: %d\n", vm_cnt.v_inactive_count);
|
|
db_printf("vm_cnt.v_active_count: %d\n", vm_cnt.v_active_count);
|
|
db_printf("vm_cnt.v_laundry_count: %d\n", vm_cnt.v_laundry_count);
|
|
db_printf("vm_cnt.v_wire_count: %d\n", vm_cnt.v_wire_count);
|
|
db_printf("vm_cnt.v_free_reserved: %d\n", vm_cnt.v_free_reserved);
|
|
db_printf("vm_cnt.v_free_min: %d\n", vm_cnt.v_free_min);
|
|
db_printf("vm_cnt.v_free_target: %d\n", vm_cnt.v_free_target);
|
|
db_printf("vm_cnt.v_inactive_target: %d\n", vm_cnt.v_inactive_target);
|
|
}
|
|
|
|
DB_SHOW_COMMAND(pageq, vm_page_print_pageq_info)
|
|
{
|
|
int dom;
|
|
|
|
db_printf("pq_free %d\n", vm_cnt.v_free_count);
|
|
for (dom = 0; dom < vm_ndomains; dom++) {
|
|
db_printf(
|
|
"dom %d page_cnt %d free %d pq_act %d pq_inact %d pq_laund %d\n",
|
|
dom,
|
|
vm_dom[dom].vmd_page_count,
|
|
vm_dom[dom].vmd_free_count,
|
|
vm_dom[dom].vmd_pagequeues[PQ_ACTIVE].pq_cnt,
|
|
vm_dom[dom].vmd_pagequeues[PQ_INACTIVE].pq_cnt,
|
|
vm_dom[dom].vmd_pagequeues[PQ_LAUNDRY].pq_cnt);
|
|
}
|
|
}
|
|
|
|
DB_SHOW_COMMAND(pginfo, vm_page_print_pginfo)
|
|
{
|
|
vm_page_t m;
|
|
boolean_t phys;
|
|
|
|
if (!have_addr) {
|
|
db_printf("show pginfo addr\n");
|
|
return;
|
|
}
|
|
|
|
phys = strchr(modif, 'p') != NULL;
|
|
if (phys)
|
|
m = PHYS_TO_VM_PAGE(addr);
|
|
else
|
|
m = (vm_page_t)addr;
|
|
db_printf(
|
|
"page %p obj %p pidx 0x%jx phys 0x%jx q %d hold %d wire %d\n"
|
|
" af 0x%x of 0x%x f 0x%x act %d busy %x valid 0x%x dirty 0x%x\n",
|
|
m, m->object, (uintmax_t)m->pindex, (uintmax_t)m->phys_addr,
|
|
m->queue, m->hold_count, m->wire_count, m->aflags, m->oflags,
|
|
m->flags, m->act_count, m->busy_lock, m->valid, m->dirty);
|
|
}
|
|
#endif /* DDB */
|