Module Name: src
Committed By: maxv
Date: Thu Jan 17 14:24:51 UTC 2019
Modified Files:
src/sys/arch/x86/x86: pmap.c
Log Message:
Simplify pmap_sync_pv: just pass a pa, and build the pte inside.
To generate a diff of this commit:
cvs rdiff -u -r1.315 -r1.316 src/sys/arch/x86/x86/pmap.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/x86/x86/pmap.c
diff -u src/sys/arch/x86/x86/pmap.c:1.315 src/sys/arch/x86/x86/pmap.c:1.316
--- src/sys/arch/x86/x86/pmap.c:1.315 Mon Dec 17 07:10:07 2018
+++ src/sys/arch/x86/x86/pmap.c Thu Jan 17 14:24:51 2019
@@ -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 s
* => 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_en
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_en
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_en
}
/*
- * 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, pad
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, unsi
{
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, unsi
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, unsi
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
{
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);
