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54d87d600a
__GFP_REPEAT has a rather weak semantic but since it has been introduced around 2.6.12 it has been ignored for low order allocations. pte_alloc_one_kernel uses __get_order_pte but this is obviously always zero because BITS_FOR_PTE is not larger than 9 yet the page size is always larger than 4K. This means that this flag has never been actually useful here because it has always been used only for PAGE_ALLOC_COSTLY requests. Link: http://lkml.kernel.org/r/1464599699-30131-7-git-send-email-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
140 lines
3.8 KiB
C
140 lines
3.8 KiB
C
/*
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* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* vineetg: June 2011
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* -"/proc/meminfo | grep PageTables" kept on increasing
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* Recently added pgtable dtor was not getting called.
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*
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* vineetg: May 2011
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* -Variable pg-sz means that Page Tables could be variable sized themselves
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* So calculate it based on addr traversal split [pgd-bits:pte-bits:xxx]
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* -Page Table size capped to max 1 to save memory - hence verified.
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* -Since these deal with constants, gcc compile-time optimizes them.
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*
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* vineetg: Nov 2010
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* -Added pgtable ctor/dtor used for pgtable mem accounting
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*
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* vineetg: April 2010
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* -Switched pgtable_t from being struct page * to unsigned long
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* =Needed so that Page Table allocator (pte_alloc_one) is not forced to
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* to deal with struct page. Thay way in future we can make it allocate
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* multiple PG Tbls in one Page Frame
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* =sweet side effect is avoiding calls to ugly page_address( ) from the
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* pg-tlb allocator sub-sys (pte_alloc_one, ptr_free, pmd_populate
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*
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* Amit Bhor, Sameer Dhavale: Codito Technologies 2004
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*/
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#ifndef _ASM_ARC_PGALLOC_H
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#define _ASM_ARC_PGALLOC_H
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#include <linux/mm.h>
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#include <linux/log2.h>
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static inline void
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pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd, pte_t *pte)
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{
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pmd_set(pmd, pte);
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}
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static inline void
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pmd_populate(struct mm_struct *mm, pmd_t *pmd, pgtable_t ptep)
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{
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pmd_set(pmd, (pte_t *) ptep);
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}
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static inline int __get_order_pgd(void)
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{
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return get_order(PTRS_PER_PGD * sizeof(pgd_t));
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}
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static inline pgd_t *pgd_alloc(struct mm_struct *mm)
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{
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int num, num2;
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pgd_t *ret = (pgd_t *) __get_free_pages(GFP_KERNEL, __get_order_pgd());
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if (ret) {
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num = USER_PTRS_PER_PGD + USER_KERNEL_GUTTER / PGDIR_SIZE;
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memzero(ret, num * sizeof(pgd_t));
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num2 = VMALLOC_SIZE / PGDIR_SIZE;
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memcpy(ret + num, swapper_pg_dir + num, num2 * sizeof(pgd_t));
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memzero(ret + num + num2,
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(PTRS_PER_PGD - num - num2) * sizeof(pgd_t));
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}
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return ret;
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}
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static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
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{
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free_pages((unsigned long)pgd, __get_order_pgd());
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}
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/*
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* With software-only page-tables, addr-split for traversal is tweakable and
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* that directly governs how big tables would be at each level.
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* Further, the MMU page size is configurable.
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* Thus we need to programatically assert the size constraint
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* All of this is const math, allowing gcc to do constant folding/propagation.
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*/
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static inline int __get_order_pte(void)
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{
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return get_order(PTRS_PER_PTE * sizeof(pte_t));
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}
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static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
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unsigned long address)
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{
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pte_t *pte;
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pte = (pte_t *) __get_free_pages(GFP_KERNEL | __GFP_ZERO,
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__get_order_pte());
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return pte;
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}
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static inline pgtable_t
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pte_alloc_one(struct mm_struct *mm, unsigned long address)
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{
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pgtable_t pte_pg;
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struct page *page;
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pte_pg = (pgtable_t)__get_free_pages(GFP_KERNEL, __get_order_pte());
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if (!pte_pg)
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return 0;
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memzero((void *)pte_pg, PTRS_PER_PTE * sizeof(pte_t));
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page = virt_to_page(pte_pg);
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if (!pgtable_page_ctor(page)) {
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__free_page(page);
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return 0;
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}
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return pte_pg;
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}
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static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
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{
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free_pages((unsigned long)pte, __get_order_pte()); /* takes phy addr */
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}
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static inline void pte_free(struct mm_struct *mm, pgtable_t ptep)
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{
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pgtable_page_dtor(virt_to_page(ptep));
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free_pages((unsigned long)ptep, __get_order_pte());
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}
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#define __pte_free_tlb(tlb, pte, addr) pte_free((tlb)->mm, pte)
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#define check_pgt_cache() do { } while (0)
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#define pmd_pgtable(pmd) ((pgtable_t) pmd_page_vaddr(pmd))
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#endif /* _ASM_ARC_PGALLOC_H */
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