mirror of
https://github.com/torvalds/linux.git
synced 2024-11-18 10:01:43 +00:00
f8829caee3
The current implementation uses a sequence of a cacheflush and a copy. This is racy in case of a multithreaded debuggee and renders GDB virtually unusable. Aside this fixes a performance hog rendering access to /proc/cmdline very slow and resulting in a enough cache stalls for the 34K AP/SP programming model to make the bare metal code on the non-Linux VPE miss RT deadlines. The main part of this patch was originally written by Ralf Baechle; Atushi Nemoto did the the debugging. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
70 lines
1.6 KiB
C
70 lines
1.6 KiB
C
/*
|
|
* This file is subject to the terms and conditions of the GNU General Public
|
|
* License. See the file "COPYING" in the main directory of this archive
|
|
* for more details.
|
|
*
|
|
* Copyright (C) 2003 by Ralf Baechle
|
|
*/
|
|
#include <linux/init.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/bootmem.h>
|
|
#include <linux/highmem.h>
|
|
#include <asm/fixmap.h>
|
|
#include <asm/pgtable.h>
|
|
|
|
void pgd_init(unsigned long page)
|
|
{
|
|
unsigned long *p = (unsigned long *) page;
|
|
int i;
|
|
|
|
for (i = 0; i < USER_PTRS_PER_PGD; i+=8) {
|
|
p[i + 0] = (unsigned long) invalid_pte_table;
|
|
p[i + 1] = (unsigned long) invalid_pte_table;
|
|
p[i + 2] = (unsigned long) invalid_pte_table;
|
|
p[i + 3] = (unsigned long) invalid_pte_table;
|
|
p[i + 4] = (unsigned long) invalid_pte_table;
|
|
p[i + 5] = (unsigned long) invalid_pte_table;
|
|
p[i + 6] = (unsigned long) invalid_pte_table;
|
|
p[i + 7] = (unsigned long) invalid_pte_table;
|
|
}
|
|
}
|
|
|
|
void __init pagetable_init(void)
|
|
{
|
|
unsigned long vaddr;
|
|
pgd_t *pgd_base;
|
|
#ifdef CONFIG_HIGHMEM
|
|
pgd_t *pgd;
|
|
pud_t *pud;
|
|
pmd_t *pmd;
|
|
pte_t *pte;
|
|
#endif
|
|
|
|
/* Initialize the entire pgd. */
|
|
pgd_init((unsigned long)swapper_pg_dir);
|
|
pgd_init((unsigned long)swapper_pg_dir
|
|
+ sizeof(pgd_t) * USER_PTRS_PER_PGD);
|
|
|
|
pgd_base = swapper_pg_dir;
|
|
|
|
/*
|
|
* Fixed mappings:
|
|
*/
|
|
vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
|
|
fixrange_init(vaddr, 0, pgd_base);
|
|
|
|
#ifdef CONFIG_HIGHMEM
|
|
/*
|
|
* Permanent kmaps:
|
|
*/
|
|
vaddr = PKMAP_BASE;
|
|
fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base);
|
|
|
|
pgd = swapper_pg_dir + __pgd_offset(vaddr);
|
|
pud = pud_offset(pgd, vaddr);
|
|
pmd = pmd_offset(pud, vaddr);
|
|
pte = pte_offset_kernel(pmd, vaddr);
|
|
pkmap_page_table = pte;
|
|
#endif
|
|
}
|