Module Name: src
Committed By: maxv
Date: Sun Aug 12 11:51:42 UTC 2018
Modified Files:
src/sys/arch/x86/x86: pmap.c
Log Message:
Reduce the minefield: zero out the pdir only once, at the beginning of
the function. This eliminates one assumption on the order of the VM
areas.
To generate a diff of this commit:
cvs rdiff -u -r1.298 -r1.299 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:1.298 src/sys/arch/x86/x86/pmap.c:1.299
--- src/sys/arch/x86/x86/pmap.c:1.298 Sun Aug 12 10:50:35 2018
+++ src/sys/arch/x86/x86/pmap.c Sun Aug 12 11:51:42 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: pmap.c,v 1.298 2018/08/12 10:50:35 maxv Exp $ */
+/* $NetBSD: pmap.c,v 1.299 2018/08/12 11:51:42 maxv Exp $ */
/*
* Copyright (c) 2008, 2010, 2016, 2017 The NetBSD Foundation, Inc.
@@ -157,7 +157,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.298 2018/08/12 10:50:35 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.299 2018/08/12 11:51:42 maxv Exp $");
#include "opt_user_ldt.h"
#include "opt_lockdebug.h"
@@ -2318,6 +2318,8 @@ pmap_pdp_ctor(void *arg, void *v, int fl
int s;
#endif
+ memset(pdir, 0, PDP_SIZE * PAGE_SIZE);
+
/*
* NOTE: The `pmaps_lock' is held when the PDP is allocated.
*/
@@ -2326,9 +2328,6 @@ pmap_pdp_ctor(void *arg, void *v, int fl
/* Fetch the physical address of the page directory */
(void)pmap_extract(pmap_kernel(), (vaddr_t)pdir, &pdirpa);
- /* Zero the area */
- memset(pdir, 0, PAGE_SIZE); /* Xen wants a clean page */
-
/*
* This pdir will NEVER be active in kernel mode, so mark
* recursive entry invalid.
@@ -2345,9 +2344,6 @@ pmap_pdp_ctor(void *arg, void *v, int fl
pdir[PDIR_SLOT_KERN + nkptp[PTP_LEVELS - 1] - 1] =
(pd_entry_t)-1 & PG_FRAME;
#else /* XEN && __x86_64__*/
- /* Zero the area */
- memset(pdir, 0, PDIR_SLOT_PTE * sizeof(pd_entry_t));
-
object = (vaddr_t)v;
for (i = 0; i < PDP_SIZE; i++, object += PAGE_SIZE) {
/* Fetch the physical address of the page directory */
@@ -2367,10 +2363,6 @@ pmap_pdp_ctor(void *arg, void *v, int fl
memcpy(&pdir[PDIR_SLOT_KERN], &PDP_BASE[PDIR_SLOT_KERN],
npde * sizeof(pd_entry_t));
- /* Zero the rest */
- memset(&pdir[PDIR_SLOT_KERN + npde], 0, (PAGE_SIZE * PDP_SIZE) -
- (PDIR_SLOT_KERN + npde) * sizeof(pd_entry_t));
-
if (VM_MIN_KERNEL_ADDRESS != KERNBASE) {
int idx = pl_i(KERNBASE, PTP_LEVELS);
pdir[idx] = PDP_BASE[idx];
