[PATCH] mm: ptd_alloc take ptlock

[linux-2.6-block.git] / mm / hugetlb.c

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index ac5f044bf5141d5bd19201b7cedc6610ca6a3876..ea0826ff2663665d2b92139339856815c4190eb9 100644 (file)
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -277,12 +277,15 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
        unsigned long addr;
 
        for (addr = vma->vm_start; addr < vma->vm_end; addr += HPAGE_SIZE) {
+               src_pte = huge_pte_offset(src, addr);
+               if (!src_pte)
+                       continue;
                dst_pte = huge_pte_alloc(dst, addr);
                if (!dst_pte)
                        goto nomem;
+               spin_lock(&dst->page_table_lock);
                spin_lock(&src->page_table_lock);
-               src_pte = huge_pte_offset(src, addr);
-               if (src_pte && !pte_none(*src_pte)) {
+               if (!pte_none(*src_pte)) {
                        entry = *src_pte;
                        ptepage = pte_page(entry);
                        get_page(ptepage);
@@ -290,6 +293,7 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
                        set_huge_pte_at(dst, addr, dst_pte, entry);
                }
                spin_unlock(&src->page_table_lock);
+               spin_unlock(&dst->page_table_lock);
        }
        return 0;
 
@@ -354,7 +358,6 @@ int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma)
 
        hugetlb_prefault_arch_hook(mm);
 
-       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);
@@ -389,11 +392,12 @@ int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma)
                                goto out;
                        }
                }
+               spin_lock(&mm->page_table_lock);
                add_mm_counter(mm, file_rss, HPAGE_SIZE / PAGE_SIZE);
                set_huge_pte_at(mm, addr, pte, make_huge_pte(vma, page));
+               spin_unlock(&mm->page_table_lock);
        }
 out:
-       spin_unlock(&mm->page_table_lock);
        return ret;
 }