2000-11-18 16:54:58

by Brian Gerst

[permalink] [raw]
Subject: [PATCH] x86 mm init cleanup

diff -urN linux-2.4.0t11p5/arch/i386/mm/init.c linux/arch/i386/mm/init.c
--- linux-2.4.0t11p5/arch/i386/mm/init.c Mon Oct 23 17:42:33 2000
+++ linux/arch/i386/mm/init.c Thu Nov 16 20:55:20 2000
@@ -315,7 +315,7 @@

static void __init pagetable_init (void)
{
- unsigned long vaddr, end;
+ unsigned long vaddr, end, __pe;
pgd_t *pgd, *pgd_base;
int i, j, k;
pmd_t *pmd;
@@ -334,11 +334,23 @@
__pgd_clear(pgd);
}
#endif
- i = __pgd_offset(PAGE_OFFSET);
+
+ __pe = _KERNPG_TABLE;
+ if (cpu_has_pse) {
+ set_in_cr4(X86_CR4_PSE);
+ __pe += _PAGE_PSE;
+ boot_cpu_data.wp_works_ok = 1;
+ if (cpu_has_pge) {
+ set_in_cr4(X86_CR4_PGE);
+ __pe += _PAGE_GLOBAL;
+ }
+ }
+
+ vaddr = PAGE_OFFSET;
+ i = __pgd_offset(vaddr);
pgd = pgd_base + i;

for (; i < PTRS_PER_PGD; pgd++, i++) {
- vaddr = i*PGDIR_SIZE;
if (end && (vaddr >= end))
break;
#if CONFIG_X86_PAE
@@ -350,35 +362,24 @@
if (pmd != pmd_offset(pgd, 0))
BUG();
for (j = 0; j < PTRS_PER_PMD; pmd++, j++) {
- vaddr = i*PGDIR_SIZE + j*PMD_SIZE;
if (end && (vaddr >= end))
break;
if (cpu_has_pse) {
- unsigned long __pe;
-
- set_in_cr4(X86_CR4_PSE);
- boot_cpu_data.wp_works_ok = 1;
- __pe = _KERNPG_TABLE + _PAGE_PSE + __pa(vaddr);
- /* Make it "global" too if supported */
- if (cpu_has_pge) {
- set_in_cr4(X86_CR4_PGE);
- __pe += _PAGE_GLOBAL;
+ set_pmd(pmd, __pmd(__pe + __pa(vaddr)));
+ vaddr += PMD_SIZE;
+ } else {
+ pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
+ set_pmd(pmd, __pmd(__pe + __pa(pte)));
+
+ if (pte != pte_offset(pmd, 0))
+ BUG();
+
+ for (k = 0; k < PTRS_PER_PTE; pte++, k++) {
+ if (end && (vaddr >= end))
+ break;
+ *pte = mk_pte_phys(__pa(vaddr), PAGE_KERNEL);
+ vaddr += PAGE_SIZE;
}
- set_pmd(pmd, __pmd(__pe));
- continue;
- }
-
- pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
- set_pmd(pmd, __pmd(_KERNPG_TABLE + __pa(pte)));
-
- if (pte != pte_offset(pmd, 0))
- BUG();
-
- for (k = 0; k < PTRS_PER_PTE; pte++, k++) {
- vaddr = i*PGDIR_SIZE + j*PMD_SIZE + k*PAGE_SIZE;
- if (end && (vaddr >= end))
- break;
- *pte = mk_pte_phys(__pa(vaddr), PAGE_KERNEL);
}
}
}


Attachments:
mminit.diff (2.17 kB)

2000-11-18 16:58:19

by Tigran Aivazian

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Subject: Re: [PATCH] x86 mm init cleanup

On Sat, 18 Nov 2000, Brian Gerst wrote:

> Patch against test11. This patch moves the setting of %cr4 out of the
> loops and makes the code a bit more readable. Tested with standard
> pagetables, PSE, and PAE.
>
>

Brian,

while you were there, so close to paging_init() why not also correct the
wrong comment at the top of the function? It talks about 0-4M pagetables
whereas we really setup (see head.S) 0-8M.

Regards,
Tigran

2000-11-18 17:12:16

by Brian Gerst

[permalink] [raw]
Subject: Re: [PATCH] x86 mm init cleanup

diff -urN linux-2.4.0t11p7/arch/i386/mm/init.c linux/arch/i386/mm/init.c
--- linux-2.4.0t11p7/arch/i386/mm/init.c Mon Oct 23 17:42:33 2000
+++ linux/arch/i386/mm/init.c Sat Nov 18 11:38:02 2000
@@ -437,7 +437,7 @@
}

/*
- * paging_init() sets up the page tables - note that the first 4MB are
+ * paging_init() sets up the page tables - note that the first 8MB are
* already mapped by head.S.
*
* This routines also unmaps the page at virtual kernel address 0, so


Attachments:
mminit2.diff (472.00 B)