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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
1.7 KiB
C
70 lines
1.7 KiB
C
/*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*
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* Copyright (C) 1999, 2000 by Silicon Graphics
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* Copyright (C) 2003 by Ralf Baechle
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*/
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#include <linux/init.h>
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#include <linux/mm.h>
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#include <asm/fixmap.h>
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#include <asm/pgtable.h>
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void pgd_init(unsigned long page)
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{
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unsigned long *p, *end;
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p = (unsigned long *) page;
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end = p + PTRS_PER_PGD;
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while (p < end) {
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p[0] = (unsigned long) invalid_pmd_table;
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p[1] = (unsigned long) invalid_pmd_table;
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p[2] = (unsigned long) invalid_pmd_table;
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p[3] = (unsigned long) invalid_pmd_table;
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p[4] = (unsigned long) invalid_pmd_table;
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p[5] = (unsigned long) invalid_pmd_table;
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p[6] = (unsigned long) invalid_pmd_table;
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p[7] = (unsigned long) invalid_pmd_table;
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p += 8;
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}
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}
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void pmd_init(unsigned long addr, unsigned long pagetable)
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{
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unsigned long *p, *end;
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p = (unsigned long *) addr;
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end = p + PTRS_PER_PMD;
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while (p < end) {
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p[0] = (unsigned long)pagetable;
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p[1] = (unsigned long)pagetable;
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p[2] = (unsigned long)pagetable;
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p[3] = (unsigned long)pagetable;
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p[4] = (unsigned long)pagetable;
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p[5] = (unsigned long)pagetable;
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p[6] = (unsigned long)pagetable;
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p[7] = (unsigned long)pagetable;
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p += 8;
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}
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}
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void __init pagetable_init(void)
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{
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unsigned long vaddr;
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pgd_t *pgd_base;
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/* Initialize the entire pgd. */
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pgd_init((unsigned long)swapper_pg_dir);
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pmd_init((unsigned long)invalid_pmd_table, (unsigned long)invalid_pte_table);
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pgd_base = swapper_pg_dir;
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/*
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* Fixed mappings:
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*/
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vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
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fixrange_init(vaddr, 0, pgd_base);
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}
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