diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/huge_memory.c | 50 |
1 files changed, 26 insertions, 24 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 8f3769ec8575..ea013cb2c3f2 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1566,35 +1566,37 @@ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, { struct mm_struct *mm = vma->vm_mm; spinlock_t *ptl; + pmd_t entry; + bool preserve_write; + int ret = 0; - if (__pmd_trans_huge_lock(pmd, vma, &ptl) == 1) { - pmd_t entry; - bool preserve_write = prot_numa && pmd_write(*pmd); - ret = 1; + if (__pmd_trans_huge_lock(pmd, vma, &ptl) != 1) + return 0; - /* - * Avoid trapping faults against the zero page. The read-only - * data is likely to be read-cached on the local CPU and - * local/remote hits to the zero page are not interesting. - */ - if (prot_numa && is_huge_zero_pmd(*pmd)) { - spin_unlock(ptl); - return ret; - } + preserve_write = prot_numa && pmd_write(*pmd); + ret = 1; - if (!prot_numa || !pmd_protnone(*pmd)) { - entry = pmdp_huge_get_and_clear_notify(mm, addr, pmd); - entry = pmd_modify(entry, newprot); - if (preserve_write) - entry = pmd_mkwrite(entry); - ret = HPAGE_PMD_NR; - set_pmd_at(mm, addr, pmd, entry); - BUG_ON(!preserve_write && pmd_write(entry)); - } - spin_unlock(ptl); - } + /* + * Avoid trapping faults against the zero page. The read-only + * data is likely to be read-cached on the local CPU and + * local/remote hits to the zero page are not interesting. + */ + if (prot_numa && is_huge_zero_pmd(*pmd)) + goto unlock; + + if (prot_numa && pmd_protnone(*pmd)) + goto unlock; + entry = pmdp_huge_get_and_clear_notify(mm, addr, pmd); + entry = pmd_modify(entry, newprot); + if (preserve_write) + entry = pmd_mkwrite(entry); + ret = HPAGE_PMD_NR; + set_pmd_at(mm, addr, pmd, entry); + BUG_ON(!preserve_write && pmd_write(entry)); +unlock: + spin_unlock(ptl); return ret; } |