From 63551ae0feaaa23807ebea60de1901564bbef32e Mon Sep 17 00:00:00 2001 From: David Gibson Date: Tue, 21 Jun 2005 17:14:44 -0700 Subject: [PATCH] Hugepage consolidation A lot of the code in arch/*/mm/hugetlbpage.c is quite similar. This patch attempts to consolidate a lot of the code across the arch's, putting the combined version in mm/hugetlb.c. There are a couple of uglyish hacks in order to covert all the hugepage archs, but the result is a very large reduction in the total amount of code. It also means things like hugepage lazy allocation could be implemented in one place, instead of six. Tested, at least a little, on ppc64, i386 and x86_64. Notes: - this patch changes the meaning of set_huge_pte() to be more analagous to set_pte() - does SH4 need s special huge_ptep_get_and_clear()?? Acked-by: William Lee Irwin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/mm/hugetlbpage.c | 170 +++------------------------------------------ 1 file changed, 8 insertions(+), 162 deletions(-) (limited to 'arch/i386') diff --git a/arch/i386/mm/hugetlbpage.c b/arch/i386/mm/hugetlbpage.c index 171fc925e1e..5aa06001a4b 100644 --- a/arch/i386/mm/hugetlbpage.c +++ b/arch/i386/mm/hugetlbpage.c @@ -18,7 +18,7 @@ #include #include -static pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr) +pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr) { pgd_t *pgd; pud_t *pud; @@ -30,7 +30,7 @@ static pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr) return (pte_t *) pmd; } -static pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) +pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) { pgd_t *pgd; pud_t *pud; @@ -42,21 +42,6 @@ static pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) return (pte_t *) pmd; } -static void set_huge_pte(struct mm_struct *mm, struct vm_area_struct *vma, struct page *page, pte_t * page_table, int write_access) -{ - pte_t entry; - - add_mm_counter(mm, rss, HPAGE_SIZE / PAGE_SIZE); - if (write_access) { - entry = - pte_mkwrite(pte_mkdirty(mk_pte(page, vma->vm_page_prot))); - } else - entry = pte_wrprotect(mk_pte(page, vma->vm_page_prot)); - entry = pte_mkyoung(entry); - mk_pte_huge(entry); - set_pte(page_table, entry); -} - /* * This function checks for proper alignment of input addr and len parameters. */ @@ -69,77 +54,6 @@ int is_aligned_hugepage_range(unsigned long addr, unsigned long len) return 0; } -int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, - struct vm_area_struct *vma) -{ - pte_t *src_pte, *dst_pte, entry; - struct page *ptepage; - unsigned long addr = vma->vm_start; - unsigned long end = vma->vm_end; - - while (addr < end) { - dst_pte = huge_pte_alloc(dst, addr); - if (!dst_pte) - goto nomem; - src_pte = huge_pte_offset(src, addr); - entry = *src_pte; - ptepage = pte_page(entry); - get_page(ptepage); - set_pte(dst_pte, entry); - add_mm_counter(dst, rss, HPAGE_SIZE / PAGE_SIZE); - addr += HPAGE_SIZE; - } - return 0; - -nomem: - return -ENOMEM; -} - -int -follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, - struct page **pages, struct vm_area_struct **vmas, - unsigned long *position, int *length, int i) -{ - unsigned long vpfn, vaddr = *position; - int remainder = *length; - - WARN_ON(!is_vm_hugetlb_page(vma)); - - vpfn = vaddr/PAGE_SIZE; - while (vaddr < vma->vm_end && remainder) { - - if (pages) { - pte_t *pte; - struct page *page; - - pte = huge_pte_offset(mm, vaddr); - - /* hugetlb should be locked, and hence, prefaulted */ - WARN_ON(!pte || pte_none(*pte)); - - page = &pte_page(*pte)[vpfn % (HPAGE_SIZE/PAGE_SIZE)]; - - WARN_ON(!PageCompound(page)); - - get_page(page); - pages[i] = page; - } - - if (vmas) - vmas[i] = vma; - - vaddr += PAGE_SIZE; - ++vpfn; - --remainder; - ++i; - } - - *length = remainder; - *position = vaddr; - - return i; -} - #if 0 /* This is just for testing */ struct page * follow_huge_addr(struct mm_struct *mm, unsigned long address, int write) @@ -204,83 +118,15 @@ follow_huge_pmd(struct mm_struct *mm, unsigned long address, } #endif -void unmap_hugepage_range(struct vm_area_struct *vma, - unsigned long start, unsigned long end) +void hugetlb_clean_stale_pgtable(pte_t *pte) { - struct mm_struct *mm = vma->vm_mm; - unsigned long address; - pte_t pte, *ptep; + pmd_t *pmd = (pmd_t *) pte; struct page *page; - BUG_ON(start & (HPAGE_SIZE - 1)); - BUG_ON(end & (HPAGE_SIZE - 1)); - - for (address = start; address < end; address += HPAGE_SIZE) { - ptep = huge_pte_offset(mm, address); - if (!ptep) - continue; - pte = ptep_get_and_clear(mm, address, ptep); - if (pte_none(pte)) - continue; - page = pte_page(pte); - put_page(page); - } - add_mm_counter(mm ,rss, -((end - start) >> PAGE_SHIFT)); - flush_tlb_range(vma, start, end); -} - -int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma) -{ - struct mm_struct *mm = current->mm; - unsigned long addr; - int ret = 0; - - BUG_ON(vma->vm_start & ~HPAGE_MASK); - BUG_ON(vma->vm_end & ~HPAGE_MASK); - - spin_lock(&mm->page_table_lock); - for (addr = vma->vm_start; addr < vma->vm_end; addr += HPAGE_SIZE) { - unsigned long idx; - pte_t *pte = huge_pte_alloc(mm, addr); - struct page *page; - - if (!pte) { - ret = -ENOMEM; - goto out; - } - - if (!pte_none(*pte)) - continue; - - idx = ((addr - vma->vm_start) >> HPAGE_SHIFT) - + (vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT)); - page = find_get_page(mapping, idx); - if (!page) { - /* charge the fs quota first */ - if (hugetlb_get_quota(mapping)) { - ret = -ENOMEM; - goto out; - } - page = alloc_huge_page(); - if (!page) { - hugetlb_put_quota(mapping); - ret = -ENOMEM; - goto out; - } - ret = add_to_page_cache(page, mapping, idx, GFP_ATOMIC); - if (! ret) { - unlock_page(page); - } else { - hugetlb_put_quota(mapping); - free_huge_page(page); - goto out; - } - } - set_huge_pte(mm, vma, page, pte, vma->vm_flags & VM_WRITE); - } -out: - spin_unlock(&mm->page_table_lock); - return ret; + page = pmd_page(*pmd); + pmd_clear(pmd); + dec_page_state(nr_page_table_pages); + page_cache_release(page); } /* x86_64 also uses this file */ -- cgit v1.2.3