Author: alc
Date: Tue Mar 10 02:12:03 2009
New Revision: 189610
URL: http://svn.freebsd.org/changeset/base/189610
Log:
Eliminate the last use of the recursive mapping to access user-space page
table pages. Now, all accesses to user-space page table pages are
performed through the direct map. (The recursive mapping is only used
to access kernel-space page table pages.)
Eliminate the TLB invalidation on the recursive mapping when a user-space
page table page is removed from the page table and when a user-space
superpage is demoted.
Modified:
head/sys/amd64/amd64/pmap.c
Modified: head/sys/amd64/amd64/pmap.c
==============================================================================
--- head/sys/amd64/amd64/pmap.c Mon Mar 9 23:25:34 2009 (r189609)
+++ head/sys/amd64/amd64/pmap.c Tue Mar 10 02:12:03 2009 (r189610)
@@ -1278,7 +1278,6 @@ static int
_pmap_unwire_pte_hold(pmap_t pmap, vm_offset_t va, vm_page_t m,
vm_page_t *free)
{
- vm_offset_t pteva;
/*
* unmap the page table page
@@ -1287,19 +1286,16 @@ _pmap_unwire_pte_hold(pmap_t pmap, vm_of
/* PDP page */
pml4_entry_t *pml4;
pml4 = pmap_pml4e(pmap, va);
- pteva = (vm_offset_t) PDPmap + amd64_ptob(m->pindex - (NUPDE +
NUPDPE));
*pml4 = 0;
} else if (m->pindex >= NUPDE) {
/* PD page */
pdp_entry_t *pdp;
pdp = pmap_pdpe(pmap, va);
- pteva = (vm_offset_t) PDmap + amd64_ptob(m->pindex - NUPDE);
*pdp = 0;
} else {
/* PTE page */
pd_entry_t *pd;
pd = pmap_pde(pmap, va);
- pteva = (vm_offset_t) PTmap + amd64_ptob(m->pindex);
*pd = 0;
}
--pmap->pm_stats.resident_count;
@@ -1325,12 +1321,6 @@ _pmap_unwire_pte_hold(pmap_t pmap, vm_of
*/
atomic_subtract_rel_int(&cnt.v_wire_count, 1);
- /*
- * Do an invltlb to make the invalidated mapping
- * take effect immediately.
- */
- pmap_invalidate_page(pmap, pteva);
-
/*
* Put page on a list so that it is released after
* *ALL* TLB shootdown is done
@@ -2277,9 +2267,10 @@ pmap_demote_pde(pmap_t pmap, pd_entry_t
pde_store(pde, newpde);
/*
- * Invalidate a stale mapping of the page table page.
+ * Invalidate a stale recursive mapping of the page table page.
*/
- pmap_invalidate_page(pmap, (vm_offset_t)vtopte(va));
+ if (va >= VM_MAXUSER_ADDRESS)
+ pmap_invalidate_page(pmap, (vm_offset_t)vtopte(va));
/*
* Demote the pv entry. This depends on the earlier demotion
@@ -3762,7 +3753,7 @@ pmap_page_is_mapped(vm_page_t m)
void
pmap_remove_pages(pmap_t pmap)
{
- pd_entry_t *pde;
+ pd_entry_t ptepde;
pt_entry_t *pte, tpte;
vm_page_t free = NULL;
vm_page_t m, mpte, mt;
@@ -3791,23 +3782,19 @@ pmap_remove_pages(pmap_t pmap)
pv = &pc->pc_pventry[idx];
inuse &= ~bitmask;
- pde = vtopde(pv->pv_va);
- tpte = *pde;
- if ((tpte & PG_PS) != 0)
- pte = pde;
- else {
+ pte = pmap_pdpe(pmap, pv->pv_va);
+ ptepde = *pte;
+ pte = pmap_pdpe_to_pde(pte, pv->pv_va);
+ tpte = *pte;
+ if ((tpte & (PG_PS | PG_V)) == PG_V) {
+ ptepde = tpte;
pte = (pt_entry_t *)PHYS_TO_DMAP(tpte &
PG_FRAME);
pte = &pte[pmap_pte_index(pv->pv_va)];
tpte = *pte & ~PG_PTE_PAT;
}
-
- if (tpte == 0) {
- printf(
- "TPTE at %p IS ZERO @ VA %08lx\n",
- pte, pv->pv_va);
+ if ((tpte & PG_V) == 0)
panic("bad pte");
- }
/*
* We cannot remove wired pages from a process' mapping at this time
@@ -3863,8 +3850,6 @@ pmap_remove_pages(pmap_t pmap)
pmap_add_delayed_free_list(mpte, &free, FALSE);
atomic_subtract_int(&cnt.v_wire_count, 1);
}
- pmap_unuse_pt(pmap, pv->pv_va,
- *pmap_pdpe(pmap, pv->pv_va), &free);
} else {
pmap->pm_stats.resident_count--;
TAILQ_REMOVE(&m->md.pv_list, pv,
pv_list);
@@ -3873,8 +3858,8 @@ pmap_remove_pages(pmap_t pmap)
if (TAILQ_EMPTY(&pvh->pv_list))
vm_page_flag_clear(m,
PG_WRITEABLE);
}
- pmap_unuse_pt(pmap, pv->pv_va, *pde,
&free);
}
+ pmap_unuse_pt(pmap, pv->pv_va, ptepde, &free);
}
}
if (allfree) {
_______________________________________________
svn-src-all@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-all
To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
