diff options
| -rw-r--r-- | include/linux/huge_mm.h | 6 | ||||
| -rw-r--r-- | mm/huge_memory.c | 23 | ||||
| -rw-r--r-- | mm/madvise.c | 2 |
3 files changed, 24 insertions, 7 deletions
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index a8b7e42..bddfba1 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -105,7 +105,8 @@ extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd); #if HPAGE_PMD_ORDER > MAX_ORDER #error "hugepages can't be allocated by the buddy allocator" #endif -extern int hugepage_madvise(unsigned long *vm_flags, int advice); +extern int hugepage_madvise(struct vm_area_struct *vma, + unsigned long *vm_flags, int advice); extern void __vma_adjust_trans_huge(struct vm_area_struct *vma, unsigned long start, unsigned long end, @@ -143,7 +144,8 @@ static inline int split_huge_page(struct page *page) do { } while (0) #define wait_split_huge_page(__anon_vma, __pmd) \ do { } while (0) -static inline int hugepage_madvise(unsigned long *vm_flags, int advice) +static inline int hugepage_madvise(struct vm_area_struct *vma, + unsigned long *vm_flags, int advice) { BUG(); return 0; diff --git a/mm/huge_memory.c b/mm/huge_memory.c index fce667c0..004c9c2 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1389,7 +1389,8 @@ out: return ret; } -int hugepage_madvise(unsigned long *vm_flags, int advice) +int hugepage_madvise(struct vm_area_struct *vma, + unsigned long *vm_flags, int advice) { switch (advice) { case MADV_HUGEPAGE: @@ -1404,6 +1405,13 @@ int hugepage_madvise(unsigned long *vm_flags, int advice) return -EINVAL; *vm_flags &= ~VM_NOHUGEPAGE; *vm_flags |= VM_HUGEPAGE; + /* + * If the vma become good for khugepaged to scan, + * register it here without waiting a page fault that + * may not happen any time soon. + */ + if (unlikely(khugepaged_enter_vma_merge(vma))) + return -ENOMEM; break; case MADV_NOHUGEPAGE: /* @@ -1417,6 +1425,11 @@ int hugepage_madvise(unsigned long *vm_flags, int advice) return -EINVAL; *vm_flags &= ~VM_HUGEPAGE; *vm_flags |= VM_NOHUGEPAGE; + /* + * Setting VM_NOHUGEPAGE will prevent khugepaged from scanning + * this vma even if we leave the mm registered in khugepaged if + * it got registered before VM_NOHUGEPAGE was set. + */ break; } @@ -1784,7 +1797,8 @@ static void collapse_huge_page(struct mm_struct *mm, if (address < hstart || address + HPAGE_PMD_SIZE > hend) goto out; - if (!(vma->vm_flags & VM_HUGEPAGE) && !khugepaged_always()) + if ((!(vma->vm_flags & VM_HUGEPAGE) && !khugepaged_always()) || + (vma->vm_flags & VM_NOHUGEPAGE)) goto out; /* VM_PFNMAP vmas may have vm_ops null but vm_file set */ @@ -2007,8 +2021,9 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages, break; } - if (!(vma->vm_flags & VM_HUGEPAGE) && - !khugepaged_always()) { + if ((!(vma->vm_flags & VM_HUGEPAGE) && + !khugepaged_always()) || + (vma->vm_flags & VM_NOHUGEPAGE)) { progress++; continue; } diff --git a/mm/madvise.c b/mm/madvise.c index bbac126..2221491 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -73,7 +73,7 @@ static long madvise_behavior(struct vm_area_struct * vma, break; case MADV_HUGEPAGE: case MADV_NOHUGEPAGE: - error = hugepage_madvise(&new_flags, behavior); + error = hugepage_madvise(vma, &new_flags, behavior); if (error) goto out; break; |
