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Eliminate the pte object.

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This commit is contained in:
Alan Cox 2003-09-27 20:53:01 +00:00
parent 9aa1994ce8
commit 9060731130
2 changed files with 49 additions and 27 deletions
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75
sys/amd64/amd64/pmap.c
View File

@ -1014,12 +1014,6 @@ pmap_pinit(pmap)
vm_page_t pml4pg;
static vm_pindex_t color;
/*
* allocate object for the ptes
*/
if (pmap->pm_pteobj == NULL)
pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, NUPDE + NUPDPE + NUPML4E + 1);
/*
* allocate the page directory page
*/
@ -1068,6 +1062,11 @@ pmap_pinit2(pmap)
/*
* this routine is called if the page table page is not
* mapped correctly.
*
* Note: If a page allocation fails at page table level two or three,
* one or two pages may be held during the wait, only to be released
* afterwards. This conservative approach is easily argued to avoid
* race conditions.
*/
static vm_page_t
_pmap_allocpte(pmap, ptepindex)
@ -1075,15 +1074,19 @@ _pmap_allocpte(pmap, ptepindex)
vm_pindex_t ptepindex;
{
vm_page_t m, pdppg, pdpg;
int is_object_locked;
/*
* Find or fabricate a new pagetable page
* Allocate a page table page.
*/
if (!(is_object_locked = VM_OBJECT_LOCKED(pmap->pm_pteobj)))
VM_OBJECT_LOCK(pmap->pm_pteobj);
m = vm_page_grab(pmap->pm_pteobj, ptepindex,
VM_ALLOC_WIRED | VM_ALLOC_ZERO | VM_ALLOC_RETRY);
if ((m = vm_page_alloc(NULL, ptepindex, VM_ALLOC_NOOBJ |
VM_ALLOC_WIRED | VM_ALLOC_ZERO)) == NULL) {
VM_WAIT;
/*
* Indicate the need to retry. While waiting, the page table
* page may have been allocated.
*/
return (NULL);
}
if ((m->flags & PG_ZERO) == 0)
pmap_zero_page(m);
@ -1125,7 +1128,13 @@ _pmap_allocpte(pmap, ptepindex)
pml4 = &pmap->pm_pml4[pml4index];
if ((*pml4 & PG_V) == 0) {
/* Have to allocate a new pdp, recurse */
_pmap_allocpte(pmap, NUPDE + NUPDPE + pml4index);
if (_pmap_allocpte(pmap, NUPDE + NUPDPE + pml4index) == NULL) {
vm_page_lock_queues();
vm_page_unhold(m);
vm_page_free(m);
vm_page_unlock_queues();
return (NULL);
}
} else {
/* Add reference to pdp page */
pdppg = PHYS_TO_VM_PAGE(*pml4);
@ -1152,7 +1161,13 @@ _pmap_allocpte(pmap, ptepindex)
pml4 = &pmap->pm_pml4[pml4index];
if ((*pml4 & PG_V) == 0) {
/* Have to allocate a new pd, recurse */
_pmap_allocpte(pmap, NUPDE + pdpindex);
if (_pmap_allocpte(pmap, NUPDE + pdpindex) == NULL) {
vm_page_lock_queues();
vm_page_unhold(m);
vm_page_free(m);
vm_page_unlock_queues();
return (NULL);
}
pdp = (pdp_entry_t *)PHYS_TO_DMAP(*pml4 & PG_FRAME);
pdp = &pdp[pdpindex & ((1ul << NPDPEPGSHIFT) - 1)];
} else {
@ -1160,7 +1175,13 @@ _pmap_allocpte(pmap, ptepindex)
pdp = &pdp[pdpindex & ((1ul << NPDPEPGSHIFT) - 1)];
if ((*pdp & PG_V) == 0) {
/* Have to allocate a new pd, recurse */
_pmap_allocpte(pmap, NUPDE + pdpindex);
if (_pmap_allocpte(pmap, NUPDE + pdpindex) == NULL) {
vm_page_lock_queues();
vm_page_unhold(m);
vm_page_free(m);
vm_page_unlock_queues();
return (NULL);
}
} else {
/* Add reference to the pd page */
pdpg = PHYS_TO_VM_PAGE(*pdp);
@ -1179,8 +1200,6 @@ _pmap_allocpte(pmap, ptepindex)
vm_page_flag_clear(m, PG_ZERO);
vm_page_wakeup(m);
vm_page_unlock_queues();
if (!is_object_locked)
VM_OBJECT_UNLOCK(pmap->pm_pteobj);
return m;
}
@ -1196,7 +1215,7 @@ pmap_allocpte(pmap_t pmap, vm_offset_t va)
* Calculate pagetable page index
*/
ptepindex = pmap_pde_pindex(va);
retry:
/*
* Get the page directory entry
*/
@ -1219,13 +1238,16 @@ pmap_allocpte(pmap_t pmap, vm_offset_t va)
if (pd != 0 && (*pd & PG_V) != 0) {
m = PHYS_TO_VM_PAGE(*pd);
m->hold_count++;
return m;
} else {
/*
* Here if the pte page isn't mapped, or if it has been
* deallocated.
*/
m = _pmap_allocpte(pmap, ptepindex);
if (m == NULL)
goto retry;
}
/*
* Here if the pte page isn't mapped, or if it has been deallocated.
*/
m = _pmap_allocpte(pmap, ptepindex);
return m;
return (m);
}
@ -1258,8 +1280,6 @@ pmap_release(pmap_t pmap)
vm_page_busy(m);
vm_page_free(m);
vm_page_unlock_queues();
KASSERT(TAILQ_EMPTY(&pmap->pm_pteobj->memq),
("pmap_release: leaking page table pages"));
}
static int
@ -1955,6 +1975,7 @@ pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte)
if (mpte && (mpte->pindex == ptepindex)) {
mpte->hold_count++;
} else {
retry:
/*
* Get the page directory entry
*/
@ -1971,6 +1992,8 @@ pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte)
mpte->hold_count++;
} else {
mpte = _pmap_allocpte(pmap, ptepindex);
if (mpte == NULL)
goto retry;
}
}
} else {

1
sys/amd64/include/pmap.h
View File

@ -219,7 +219,6 @@ struct md_page {
struct pmap {
pml4_entry_t *pm_pml4; /* KVA of level 4 page table */
vm_object_t pm_pteobj; /* Container for pte's */
TAILQ_HEAD(,pv_entry) pm_pvlist; /* list of mappings in pmap */
u_long pm_active; /* active on cpus */
struct pmap_statistics pm_stats; /* pmap statistics */