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Simplify pmap_sync_pv: just pass a pa, and build the pte inside.

This commit is contained in:
maxv 2019-01-17 14:24:51 +00:00
parent 47334d6753
commit 73b2ed774d
1 changed files with 21 additions and 33 deletions
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54
sys/arch/x86/x86/pmap.c
View File

@ -1,4 +1,4 @@
/* $NetBSD: pmap.c,v 1.315 2018/12/17 07:10:07 maxv Exp $ */
/* $NetBSD: pmap.c,v 1.316 2019/01/17 14:24:51 maxv Exp $ */
/*
* Copyright (c) 2008, 2010, 2016, 2017 The NetBSD Foundation, Inc.
@ -130,7 +130,7 @@
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.315 2018/12/17 07:10:07 maxv Exp $");
__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.316 2019/01/17 14:24:51 maxv Exp $");
#include "opt_user_ldt.h"
#include "opt_lockdebug.h"
@ -3579,8 +3579,7 @@ pmap_remove(struct pmap *pmap, vaddr_t sva, vaddr_t eva)
* => issues tlb shootdowns if necessary.
*/
static int
pmap_sync_pv(struct pv_pte *pvpte, pt_entry_t expect, int clearbits,
pt_entry_t *optep)
pmap_sync_pv(struct pv_pte *pvpte, paddr_t pa, int clearbits, pt_entry_t *optep)
{
struct pmap *pmap;
struct vm_page *ptp;
@ -3588,16 +3587,16 @@ pmap_sync_pv(struct pv_pte *pvpte, pt_entry_t expect, int clearbits,
pt_entry_t *ptep;
pt_entry_t opte;
pt_entry_t npte;
pt_entry_t expect;
bool need_shootdown;
expect = pmap_pa2pte(pa) | PG_V;
ptp = pvpte->pte_ptp;
va = pvpte->pte_va;
KASSERT(ptp == NULL || ptp->uobject != NULL);
KASSERT(ptp == NULL || ptp_va2o(va, 1) == ptp->offset);
pmap = ptp_to_pmap(ptp);
KASSERT((expect & ~(PG_FRAME | PG_V)) == 0);
KASSERT((expect & PG_V) != 0);
KASSERT(clearbits == ~0 || (clearbits & ~(PG_M | PG_U | PG_RW)) == 0);
KASSERT(kpreempt_disabled());
@ -3608,16 +3607,14 @@ pmap_sync_pv(struct pv_pte *pvpte, pt_entry_t expect, int clearbits,
KASSERT((opte & (PG_U | PG_V)) != PG_U);
KASSERT(opte == 0 || (opte & PG_V) != 0);
if ((opte & (PG_FRAME | PG_V)) != expect) {
/*
* we lost a race with a V->P operation like
* pmap_remove(). wait for the competitor
* We lost a race with a V->P operation like
* pmap_remove(). Wait for the competitor
* reflecting pte bits into mp_attrs.
*
* issue a redundant TLB shootdown so that
* Issue a redundant TLB shootdown so that
* we can wait for its completion.
*/
pmap_unmap_pte();
if (clearbits != 0) {
pmap_tlb_shootdown(pmap, va,
@ -3628,30 +3625,26 @@ pmap_sync_pv(struct pv_pte *pvpte, pt_entry_t expect, int clearbits,
}
/*
* check if there's anything to do on this pte.
* Check if there's anything to do on this PTE.
*/
if ((opte & clearbits) == 0) {
need_shootdown = false;
break;
}
/*
* we need a shootdown if the pte is cached. (PG_U)
*
* ...unless we are clearing only the PG_RW bit and
* it isn't cached as RW. (PG_M)
* We need a shootdown if the PTE is cached (PG_U) ...
* ... Unless we are clearing only the PG_RW bit and
* it isn't cached as RW (PG_M).
*/
need_shootdown = (opte & PG_U) != 0 &&
!(clearbits == PG_RW && (opte & PG_M) == 0);
npte = opte & ~clearbits;
/*
* if we need a shootdown anyway, clear PG_U and PG_M.
* If we need a shootdown anyway, clear PG_U and PG_M.
*/
if (need_shootdown) {
npte &= ~(PG_U | PG_M);
}
@ -3675,10 +3668,8 @@ pmap_pp_remove(struct pmap_page *pp, paddr_t pa)
struct pv_pte *pvpte;
struct pv_entry *killlist = NULL;
struct vm_page *ptp;
pt_entry_t expect;
int count;
expect = pmap_pa2pte(pa) | PG_V;
count = SPINLOCK_BACKOFF_MIN;
kpreempt_disable();
startover:
@ -3690,17 +3681,16 @@ startover:
int error;
/*
* add a reference to the pmap before clearing the pte.
* otherwise the pmap can disappear behind us.
* Add a reference to the pmap before clearing the pte.
* Otherwise the pmap can disappear behind us.
*/
ptp = pvpte->pte_ptp;
pmap = ptp_to_pmap(ptp);
if (ptp != NULL) {
pmap_reference(pmap);
}
error = pmap_sync_pv(pvpte, expect, ~0, &opte);
error = pmap_sync_pv(pvpte, pa, ~0, &opte);
if (error == EAGAIN) {
int hold_count;
KERNEL_UNLOCK_ALL(curlwp, &hold_count);
@ -3716,7 +3706,7 @@ startover:
va = pvpte->pte_va;
pve = pmap_remove_pv(pp, ptp, va);
/* update the PTP reference count. free if last reference. */
/* Update the PTP reference count. Free if last reference. */
if (ptp != NULL) {
struct pmap *pmap2;
pt_entry_t *ptes;
@ -3798,8 +3788,8 @@ pmap_test_attrs(struct vm_page *pg, unsigned testbits)
{
struct pmap_page *pp;
struct pv_pte *pvpte;
pt_entry_t expect;
u_int result;
paddr_t pa;
KASSERT(uvm_page_locked_p(pg));
@ -3807,7 +3797,7 @@ pmap_test_attrs(struct vm_page *pg, unsigned testbits)
if ((pp->pp_attrs & testbits) != 0) {
return true;
}
expect = pmap_pa2pte(VM_PAGE_TO_PHYS(pg)) | PG_V;
pa = VM_PAGE_TO_PHYS(pg);
kpreempt_disable();
for (pvpte = pv_pte_first(pp); pvpte; pvpte = pv_pte_next(pp, pvpte)) {
pt_entry_t opte;
@ -3816,7 +3806,7 @@ pmap_test_attrs(struct vm_page *pg, unsigned testbits)
if ((pp->pp_attrs & testbits) != 0) {
break;
}
error = pmap_sync_pv(pvpte, expect, 0, &opte);
error = pmap_sync_pv(pvpte, pa, 0, &opte);
if (error == 0) {
pp->pp_attrs |= opte;
}
@ -3837,10 +3827,8 @@ pmap_pp_clear_attrs(struct pmap_page *pp, paddr_t pa, unsigned clearbits)
{
struct pv_pte *pvpte;
u_int result;
pt_entry_t expect;
int count;
expect = pmap_pa2pte(pa) | PG_V;
count = SPINLOCK_BACKOFF_MIN;
kpreempt_disable();
startover:
@ -3848,7 +3836,7 @@ startover:
pt_entry_t opte;
int error;
error = pmap_sync_pv(pvpte, expect, clearbits, &opte);
error = pmap_sync_pv(pvpte, pa, clearbits, &opte);
if (error == EAGAIN) {
int hold_count;
KERNEL_UNLOCK_ALL(curlwp, &hold_count);