From 508034a32b819a2d40aa7ac0dbc8cd2e044c2de6 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Sat, 29 Oct 2005 18:16:30 -0700 Subject: [PATCH] mm: unmap_vmas with inner ptlock Remove the page_table_lock from around the calls to unmap_vmas, and replace the pte_offset_map in zap_pte_range by pte_offset_map_lock: all callers are now safe to descend without page_table_lock. Don't attempt fancy locking for hugepages, just take page_table_lock in unmap_hugepage_range. Which makes zap_hugepage_range, and the hugetlb test in zap_page_range, redundant: unmap_vmas calls unmap_hugepage_range anyway. Nor does unmap_vmas have much use for its mm arg now. The tlb_start_vma and tlb_end_vma in unmap_page_range are now called without page_table_lock: if they're implemented at all, they typically come down to flush_cache_range (usually done outside page_table_lock) and flush_tlb_range (which we already audited for the mprotect case). Signed-off-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb.c | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-) (limited to 'mm/hugetlb.c') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index ea0826ff266..f29b7dc02c3 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -314,6 +314,8 @@ void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, BUG_ON(start & ~HPAGE_MASK); BUG_ON(end & ~HPAGE_MASK); + spin_lock(&mm->page_table_lock); + /* Update high watermark before we lower rss */ update_hiwater_rss(mm); @@ -333,17 +335,9 @@ void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, put_page(page); add_mm_counter(mm, file_rss, (int) -(HPAGE_SIZE / PAGE_SIZE)); } - flush_tlb_range(vma, start, end); -} -void zap_hugepage_range(struct vm_area_struct *vma, - unsigned long start, unsigned long length) -{ - struct mm_struct *mm = vma->vm_mm; - - spin_lock(&mm->page_table_lock); - unmap_hugepage_range(vma, start, start + length); spin_unlock(&mm->page_table_lock); + flush_tlb_range(vma, start, end); } int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma) -- cgit v1.2.3