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-rw-r--r--mm/huge_memory.c52
1 files changed, 26 insertions, 26 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index fef4cf210cc7..a513861a9037 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1724,37 +1724,37 @@ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
1724{ 1724{
1725 struct mm_struct *mm = vma->vm_mm; 1725 struct mm_struct *mm = vma->vm_mm;
1726 spinlock_t *ptl; 1726 spinlock_t *ptl;
1727 int ret = 0; 1727 pmd_t entry;
1728 bool preserve_write;
1729 int ret;
1728 1730
1729 ptl = __pmd_trans_huge_lock(pmd, vma); 1731 ptl = __pmd_trans_huge_lock(pmd, vma);
1730 if (ptl) { 1732 if (!ptl)
1731 pmd_t entry; 1733 return 0;
1732 bool preserve_write = prot_numa && pmd_write(*pmd);
1733 ret = 1;
1734 1734
1735 /* 1735 preserve_write = prot_numa && pmd_write(*pmd);
1736 * Avoid trapping faults against the zero page. The read-only 1736 ret = 1;
1737 * data is likely to be read-cached on the local CPU and
1738 * local/remote hits to the zero page are not interesting.
1739 */
1740 if (prot_numa && is_huge_zero_pmd(*pmd)) {
1741 spin_unlock(ptl);
1742 return ret;
1743 }
1744 1737
1745 if (!prot_numa || !pmd_protnone(*pmd)) { 1738 /*
1746 entry = pmdp_huge_get_and_clear_notify(mm, addr, pmd); 1739 * Avoid trapping faults against the zero page. The read-only
1747 entry = pmd_modify(entry, newprot); 1740 * data is likely to be read-cached on the local CPU and
1748 if (preserve_write) 1741 * local/remote hits to the zero page are not interesting.
1749 entry = pmd_mk_savedwrite(entry); 1742 */
1750 ret = HPAGE_PMD_NR; 1743 if (prot_numa && is_huge_zero_pmd(*pmd))
1751 set_pmd_at(mm, addr, pmd, entry); 1744 goto unlock;
1752 BUG_ON(vma_is_anonymous(vma) && !preserve_write &&
1753 pmd_write(entry));
1754 }
1755 spin_unlock(ptl);
1756 }
1757 1745
1746 if (prot_numa && pmd_protnone(*pmd))
1747 goto unlock;
1748
1749 entry = pmdp_huge_get_and_clear_notify(mm, addr, pmd);
1750 entry = pmd_modify(entry, newprot);
1751 if (preserve_write)
1752 entry = pmd_mk_savedwrite(entry);
1753 ret = HPAGE_PMD_NR;
1754 set_pmd_at(mm, addr, pmd, entry);
1755 BUG_ON(vma_is_anonymous(vma) && !preserve_write && pmd_write(entry));
1756unlock:
1757 spin_unlock(ptl);
1758 return ret; 1758 return ret;
1759} 1759}
1760 1760