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For efficiency eliminate the call to pmap_pte() from pmap_protect()'s and

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pmap_remove()'s inner loop.  Instead, call pmap_pde_to_pte(), a new
function, prior to the inner loop.

Reviewed by: peter@, tegge@
This commit is contained in:
Alan Cox 2004-12-02 04:06:40 +00:00
parent 4878c3cdba
commit 664c816978
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=138304
1 changed files with 18 additions and 14 deletions
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32
sys/amd64/amd64/pmap.c
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@ -316,20 +316,28 @@ pmap_pde(pmap_t pmap, vm_offset_t va)
return (&pde[pmap_pde_index(va)]);
}
/* Return a pointer to the PT slot that corresponds to a VA */
static __inline pt_entry_t *
pmap_pde_to_pte(pd_entry_t *pde, vm_offset_t va)
{
pt_entry_t *pte;
pte = (pt_entry_t *)PHYS_TO_DMAP(*pde & PG_FRAME);
return (&pte[pmap_pte_index(va)]);
}
/* Return a pointer to the PT slot that corresponds to a VA */
static __inline pt_entry_t *
pmap_pte(pmap_t pmap, vm_offset_t va)
{
pd_entry_t *pde;
pt_entry_t *pte;
pde = pmap_pde(pmap, va);
if (pde == NULL || (*pde & PG_V) == 0)
return NULL;
if ((*pde & PG_PS) != 0) /* compat with i386 pmap_pte() */
return ((pt_entry_t *)pde);
pte = (pt_entry_t *)PHYS_TO_DMAP(*pde & PG_FRAME);
return (&pte[pmap_pte_index(va)]);
return (pmap_pde_to_pte(pde, va));
}
@ -337,7 +345,6 @@ static __inline pt_entry_t *
pmap_pte_pde(pmap_t pmap, vm_offset_t va, pd_entry_t *ptepde)
{
pd_entry_t *pde;
pt_entry_t *pte;
pde = pmap_pde(pmap, va);
if (pde == NULL || (*pde & PG_V) == 0)
@ -345,8 +352,7 @@ pmap_pte_pde(pmap_t pmap, vm_offset_t va, pd_entry_t *ptepde)
*ptepde = *pde;
if ((*pde & PG_PS) != 0) /* compat with i386 pmap_pte() */
return ((pt_entry_t *)pde);
pte = (pt_entry_t *)PHYS_TO_DMAP(*pde & PG_FRAME);
return (&pte[pmap_pte_index(va)]);
return (pmap_pde_to_pte(pde, va));
}
@ -1630,9 +1636,9 @@ pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
if (va_next > eva)
va_next = eva;
for (; sva != va_next; sva += PAGE_SIZE) {
pte = pmap_pte(pmap, sva);
if (pte == NULL || *pte == 0)
for (pte = pmap_pde_to_pte(pde, sva); sva != va_next; pte++,
sva += PAGE_SIZE) {
if (*pte == 0)
continue;
anyvalid = 1;
if (pmap_remove_pte(pmap, pte, sva, ptpaddr))
@ -1722,6 +1728,7 @@ pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
pml4_entry_t *pml4e;
pdp_entry_t *pdpe;
pd_entry_t ptpaddr, *pde;
pt_entry_t *pte;
int anychanged;
if ((prot & VM_PROT_READ) == VM_PROT_NONE) {
@ -1777,14 +1784,11 @@ pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
if (va_next > eva)
va_next = eva;
for (; sva != va_next; sva += PAGE_SIZE) {
for (pte = pmap_pde_to_pte(pde, sva); sva != va_next; pte++,
sva += PAGE_SIZE) {
pt_entry_t obits, pbits;
pt_entry_t *pte;
vm_page_t m;
pte = pmap_pte(pmap, sva);
if (pte == NULL)
continue;
retry:
obits = pbits = *pte;
if (pbits & PG_MANAGED) {