Introduce vm_reserv_alloc_contig() and teach vm_page_alloc_contig() how to

use superpage reservations.  So, for the first time, kernel virtual memory
that is allocated by contigmalloc(), kmem_alloc_attr(), and
kmem_alloc_contig() can be promoted to superpages.  In fact, even a series
of small contigmalloc() allocations may collectively result in a promoted
superpage.

Eliminate some duplication of code in vm_reserv_alloc_page().

Change the type of vm_reserv_reclaim_contig()'s first parameter in order
that it be consistent with other vm_*_contig() functions.

Tested by:	marius (sparc64)
This commit is contained in:
alc 2011-12-05 18:29:25 +00:00
parent f47c7431de
commit a8855af4c0
3 changed files with 271 additions and 73 deletions

View File

@ -1554,9 +1554,12 @@ vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req,
cnt.v_free_count + cnt.v_cache_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);
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);
@ -1581,8 +1584,8 @@ vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req,
}
else {
#if VM_NRESERVLEVEL > 0
if (vm_reserv_reclaim_contig(npages << PAGE_SHIFT, low, high,
alignment, boundary))
if (vm_reserv_reclaim_contig(npages, low, high, alignment,
boundary))
goto retry;
#endif
}

View File

@ -31,6 +31,9 @@
/*
* Superpage reservation management module
*
* Any external functions defined by this module are only to be used by the
* virtual memory system.
*/
#include <sys/cdefs.h>
@ -284,6 +287,201 @@ vm_reserv_populate(vm_reserv_t rv)
}
}
/*
* Allocates a contiguous set of physical pages of the given size "npages"
* from an existing or newly-created reservation. 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.
*
* The object and free page queue must be locked.
*/
vm_page_t
vm_reserv_alloc_contig(vm_object_t object, vm_pindex_t pindex, u_long npages,
vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary)
{
vm_paddr_t pa, size;
vm_page_t m, m_ret, mpred, msucc;
vm_pindex_t first, leftcap, rightcap;
vm_reserv_t rv;
u_long allocpages, maxpages, minpages;
int i, index, n;
mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
VM_OBJECT_LOCK_ASSERT(object, MA_OWNED);
KASSERT(npages != 0, ("vm_reserv_alloc_contig: npages is 0"));
/*
* Is a reservation fundamentally impossible?
*/
if (pindex < VM_RESERV_INDEX(object, pindex) ||
pindex + npages > object->size)
return (NULL);
/*
* All reservations of a particular size have the same alignment.
* Assuming that the first page is allocated from a reservation, the
* least significant bits of its physical address can be determined
* from its offset from the beginning of the reservation and the size
* of the reservation.
*
* Could the specified index within a reservation of the smallest
* possible size satisfy the alignment and boundary requirements?
*/
pa = VM_RESERV_INDEX(object, pindex) << PAGE_SHIFT;
if ((pa & (alignment - 1)) != 0)
return (NULL);
size = npages << PAGE_SHIFT;
if (((pa ^ (pa + size - 1)) & ~(boundary - 1)) != 0)
return (NULL);
/*
* Look for an existing reservation.
*/
msucc = NULL;
mpred = object->root;
while (mpred != NULL) {
KASSERT(mpred->pindex != pindex,
("vm_reserv_alloc_contig: pindex already allocated"));
rv = vm_reserv_from_page(mpred);
if (rv->object == object && vm_reserv_has_pindex(rv, pindex))
goto found;
else if (mpred->pindex < pindex) {
if (msucc != NULL ||
(msucc = TAILQ_NEXT(mpred, listq)) == NULL)
break;
KASSERT(msucc->pindex != pindex,
("vm_reserv_alloc_contig: pindex already allocated"));
rv = vm_reserv_from_page(msucc);
if (rv->object == object &&
vm_reserv_has_pindex(rv, pindex))
goto found;
else if (pindex < msucc->pindex)
break;
} else if (msucc == NULL) {
msucc = mpred;
mpred = TAILQ_PREV(msucc, pglist, listq);
continue;
}
msucc = NULL;
mpred = object->root = vm_page_splay(pindex, object->root);
}
/*
* Could at least one reservation fit between the first index to the
* left that can be used and the first index to the right that cannot
* be used?
*/
first = pindex - VM_RESERV_INDEX(object, pindex);
if (mpred != NULL) {
if ((rv = vm_reserv_from_page(mpred))->object != object)
leftcap = mpred->pindex + 1;
else
leftcap = rv->pindex + VM_LEVEL_0_NPAGES;
if (leftcap > first)
return (NULL);
}
minpages = VM_RESERV_INDEX(object, pindex) + npages;
maxpages = roundup2(minpages, VM_LEVEL_0_NPAGES);
allocpages = maxpages;
if (msucc != NULL) {
if ((rv = vm_reserv_from_page(msucc))->object != object)
rightcap = msucc->pindex;
else
rightcap = rv->pindex;
if (first + maxpages > rightcap) {
if (maxpages == VM_LEVEL_0_NPAGES)
return (NULL);
allocpages = minpages;
}
}
/*
* Would the last new reservation extend past the end of the object?
*/
if (first + maxpages > object->size) {
/*
* Don't allocate the last new reservation if the object is a
* vnode or backed by another object that is a vnode.
*/
if (object->type == OBJT_VNODE ||
(object->backing_object != NULL &&
object->backing_object->type == OBJT_VNODE)) {
if (maxpages == VM_LEVEL_0_NPAGES)
return (NULL);
allocpages = minpages;
}
/* Speculate that the object may grow. */
}
/*
* Allocate and populate the new reservations. The alignment and
* boundary specified for this allocation may be different from the
* alignment and boundary specified for the requested pages. For
* instance, the specified index may not be the first page within the
* first new reservation.
*/
m = vm_phys_alloc_contig(allocpages, low, high, ulmax(alignment,
VM_LEVEL_0_SIZE), boundary > VM_LEVEL_0_SIZE ? boundary : 0);
if (m == NULL)
return (NULL);
m_ret = NULL;
index = VM_RESERV_INDEX(object, pindex);
do {
rv = vm_reserv_from_page(m);
KASSERT(rv->pages == m,
("vm_reserv_alloc_contig: reserv %p's pages is corrupted",
rv));
KASSERT(rv->object == NULL,
("vm_reserv_alloc_contig: reserv %p isn't free", rv));
LIST_INSERT_HEAD(&object->rvq, rv, objq);
rv->object = object;
rv->pindex = first;
KASSERT(rv->popcnt == 0,
("vm_reserv_alloc_contig: reserv %p's popcnt is corrupted",
rv));
KASSERT(!rv->inpartpopq,
("vm_reserv_alloc_contig: reserv %p's inpartpopq is TRUE",
rv));
n = ulmin(VM_LEVEL_0_NPAGES - index, npages);
for (i = 0; i < n; i++)
vm_reserv_populate(rv);
npages -= n;
if (m_ret == NULL) {
m_ret = &rv->pages[index];
index = 0;
}
m += VM_LEVEL_0_NPAGES;
first += VM_LEVEL_0_NPAGES;
allocpages -= VM_LEVEL_0_NPAGES;
} while (allocpages > VM_LEVEL_0_NPAGES);
return (m_ret);
/*
* Found a matching reservation.
*/
found:
index = VM_RESERV_INDEX(object, pindex);
/* Does the allocation fit within the reservation? */
if (index + npages > VM_LEVEL_0_NPAGES)
return (NULL);
m = &rv->pages[index];
pa = VM_PAGE_TO_PHYS(m);
if (pa < low || pa + size > high || (pa & (alignment - 1)) != 0 ||
((pa ^ (pa + size - 1)) & ~(boundary - 1)) != 0)
return (NULL);
/* Handle vm_page_rename(m, new_object, ...). */
for (i = 0; i < npages; i++)
if ((rv->pages[index + i].flags & (PG_CACHED | PG_FREE)) == 0)
return (NULL);
for (i = 0; i < npages; i++)
vm_reserv_populate(rv);
return (m);
}
/*
* Allocates a page from an existing or newly-created reservation.
*
@ -297,11 +495,11 @@ vm_reserv_alloc_page(vm_object_t object, vm_pindex_t pindex)
vm_reserv_t rv;
mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
VM_OBJECT_LOCK_ASSERT(object, MA_OWNED);
/*
* Is a reservation fundamentally not possible?
* Is a reservation fundamentally impossible?
*/
VM_OBJECT_LOCK_ASSERT(object, MA_OWNED);
if (pindex < VM_RESERV_INDEX(object, pindex) ||
pindex >= object->size)
return (NULL);
@ -315,14 +513,9 @@ vm_reserv_alloc_page(vm_object_t object, vm_pindex_t pindex)
KASSERT(mpred->pindex != pindex,
("vm_reserv_alloc_page: pindex already allocated"));
rv = vm_reserv_from_page(mpred);
if (rv->object == object && vm_reserv_has_pindex(rv, pindex)) {
m = &rv->pages[VM_RESERV_INDEX(object, pindex)];
/* Handle vm_page_rename(m, new_object, ...). */
if ((m->flags & (PG_CACHED | PG_FREE)) == 0)
return (NULL);
vm_reserv_populate(rv);
return (m);
} else if (mpred->pindex < pindex) {
if (rv->object == object && vm_reserv_has_pindex(rv, pindex))
goto found;
else if (mpred->pindex < pindex) {
if (msucc != NULL ||
(msucc = TAILQ_NEXT(mpred, listq)) == NULL)
break;
@ -330,14 +523,9 @@ vm_reserv_alloc_page(vm_object_t object, vm_pindex_t pindex)
("vm_reserv_alloc_page: pindex already allocated"));
rv = vm_reserv_from_page(msucc);
if (rv->object == object &&
vm_reserv_has_pindex(rv, pindex)) {
m = &rv->pages[VM_RESERV_INDEX(object, pindex)];
/* Handle vm_page_rename(m, new_object, ...). */
if ((m->flags & (PG_CACHED | PG_FREE)) == 0)
return (NULL);
vm_reserv_populate(rv);
return (m);
} else if (pindex < msucc->pindex)
vm_reserv_has_pindex(rv, pindex))
goto found;
else if (pindex < msucc->pindex)
break;
} else if (msucc == NULL) {
msucc = mpred;
@ -349,38 +537,31 @@ vm_reserv_alloc_page(vm_object_t object, vm_pindex_t pindex)
}
/*
* Determine the first index to the left that can be used.
*/
if (mpred == NULL)
leftcap = 0;
else if ((rv = vm_reserv_from_page(mpred))->object != object)
leftcap = mpred->pindex + 1;
else
leftcap = rv->pindex + VM_LEVEL_0_NPAGES;
/*
* Determine the first index to the right that cannot be used.
*/
if (msucc == NULL)
rightcap = pindex + VM_LEVEL_0_NPAGES;
else if ((rv = vm_reserv_from_page(msucc))->object != object)
rightcap = msucc->pindex;
else
rightcap = rv->pindex;
/*
* Determine if a reservation fits between the first index to
* the left that can be used and the first index to the right
* that cannot be used.
* Could a reservation fit between the first index to the left that
* can be used and the first index to the right that cannot be used?
*/
first = pindex - VM_RESERV_INDEX(object, pindex);
if (first < leftcap || first + VM_LEVEL_0_NPAGES > rightcap)
return (NULL);
if (mpred != NULL) {
if ((rv = vm_reserv_from_page(mpred))->object != object)
leftcap = mpred->pindex + 1;
else
leftcap = rv->pindex + VM_LEVEL_0_NPAGES;
if (leftcap > first)
return (NULL);
}
if (msucc != NULL) {
if ((rv = vm_reserv_from_page(msucc))->object != object)
rightcap = msucc->pindex;
else
rightcap = rv->pindex;
if (first + VM_LEVEL_0_NPAGES > rightcap)
return (NULL);
}
/*
* Would a new reservation extend past the end of the given object?
* Would a new reservation extend past the end of the object?
*/
if (object->size < first + VM_LEVEL_0_NPAGES) {
if (first + VM_LEVEL_0_NPAGES > object->size) {
/*
* Don't allocate a new reservation if the object is a vnode or
* backed by another object that is a vnode.
@ -393,28 +574,35 @@ vm_reserv_alloc_page(vm_object_t object, vm_pindex_t pindex)
}
/*
* Allocate a new reservation.
* Allocate and populate the new reservation.
*/
m = vm_phys_alloc_pages(VM_FREEPOOL_DEFAULT, VM_LEVEL_0_ORDER);
if (m != NULL) {
rv = vm_reserv_from_page(m);
KASSERT(rv->pages == m,
("vm_reserv_alloc_page: reserv %p's pages is corrupted",
rv));
KASSERT(rv->object == NULL,
("vm_reserv_alloc_page: reserv %p isn't free", rv));
LIST_INSERT_HEAD(&object->rvq, rv, objq);
rv->object = object;
rv->pindex = first;
KASSERT(rv->popcnt == 0,
("vm_reserv_alloc_page: reserv %p's popcnt is corrupted",
rv));
KASSERT(!rv->inpartpopq,
("vm_reserv_alloc_page: reserv %p's inpartpopq is TRUE",
rv));
vm_reserv_populate(rv);
m = &rv->pages[VM_RESERV_INDEX(object, pindex)];
}
if (m == NULL)
return (NULL);
rv = vm_reserv_from_page(m);
KASSERT(rv->pages == m,
("vm_reserv_alloc_page: reserv %p's pages is corrupted", rv));
KASSERT(rv->object == NULL,
("vm_reserv_alloc_page: reserv %p isn't free", rv));
LIST_INSERT_HEAD(&object->rvq, rv, objq);
rv->object = object;
rv->pindex = first;
KASSERT(rv->popcnt == 0,
("vm_reserv_alloc_page: reserv %p's popcnt is corrupted", rv));
KASSERT(!rv->inpartpopq,
("vm_reserv_alloc_page: reserv %p's inpartpopq is TRUE", rv));
vm_reserv_populate(rv);
return (&rv->pages[VM_RESERV_INDEX(object, pindex)]);
/*
* Found a matching reservation.
*/
found:
m = &rv->pages[VM_RESERV_INDEX(object, pindex)];
/* Handle vm_page_rename(m, new_object, ...). */
if ((m->flags & (PG_CACHED | PG_FREE)) == 0)
return (NULL);
vm_reserv_populate(rv);
return (m);
}
@ -627,16 +815,17 @@ vm_reserv_reclaim_inactive(void)
* The free page queue lock must be held.
*/
boolean_t
vm_reserv_reclaim_contig(vm_paddr_t size, vm_paddr_t low, vm_paddr_t high,
vm_reserv_reclaim_contig(u_long npages, vm_paddr_t low, vm_paddr_t high,
u_long alignment, vm_paddr_t boundary)
{
vm_paddr_t pa, pa_length;
vm_paddr_t pa, pa_length, size;
vm_reserv_t rv;
int i;
mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
if (size > VM_LEVEL_0_SIZE - PAGE_SIZE)
if (npages > VM_LEVEL_0_NPAGES - 1)
return (FALSE);
size = npages << PAGE_SHIFT;
TAILQ_FOREACH(rv, &vm_rvq_partpop, partpopq) {
pa = VM_PAGE_TO_PHYS(&rv->pages[VM_LEVEL_0_NPAGES - 1]);
if (pa + PAGE_SIZE - size < low) {

View File

@ -42,13 +42,19 @@
#if VM_NRESERVLEVEL > 0
/*
* The following functions are only to be used by the virtual memory system.
*/
vm_page_t vm_reserv_alloc_contig(vm_object_t object, vm_pindex_t pindex,
u_long npages, vm_paddr_t low, vm_paddr_t high,
u_long alignment, vm_paddr_t boundary);
vm_page_t vm_reserv_alloc_page(vm_object_t object, vm_pindex_t pindex);
void vm_reserv_break_all(vm_object_t object);
boolean_t vm_reserv_free_page(vm_page_t m);
void vm_reserv_init(void);
int vm_reserv_level_iffullpop(vm_page_t m);
boolean_t vm_reserv_reactivate_page(vm_page_t m);
boolean_t vm_reserv_reclaim_contig(vm_paddr_t size, vm_paddr_t low,
boolean_t vm_reserv_reclaim_contig(u_long npages, vm_paddr_t low,
vm_paddr_t high, u_long alignment, vm_paddr_t boundary);
boolean_t vm_reserv_reclaim_inactive(void);
void vm_reserv_rename(vm_page_t m, vm_object_t new_object,