diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/huge_memory.c | 43 | ||||
| -rw-r--r-- | mm/internal.h | 4 | ||||
| -rw-r--r-- | mm/memory.c | 2 |
3 files changed, 45 insertions, 4 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index ed474483a620..b11351579e7a 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2373,6 +2373,44 @@ static bool hugepage_vma_check(struct vm_area_struct *vma) return !(vma->vm_flags & VM_NO_THP); } +/* + * Bring missing pages in from swap, to complete THP collapse. + * Only done if khugepaged_scan_pmd believes it is worthwhile. + * + * Called and returns without pte mapped or spinlocks held, + * but with mmap_sem held to protect against vma changes. + */ + +static void __collapse_huge_page_swapin(struct mm_struct *mm, + struct vm_area_struct *vma, + unsigned long address, pmd_t *pmd) +{ + unsigned long _address; + pte_t *pte, pteval; + int swapped_in = 0, ret = 0; + + pte = pte_offset_map(pmd, address); + for (_address = address; _address < address + HPAGE_PMD_NR*PAGE_SIZE; + pte++, _address += PAGE_SIZE) { + pteval = *pte; + if (!is_swap_pte(pteval)) + continue; + swapped_in++; + ret = do_swap_page(mm, vma, _address, pte, pmd, + FAULT_FLAG_ALLOW_RETRY|FAULT_FLAG_RETRY_NOWAIT, + pteval); + if (ret & VM_FAULT_ERROR) { + trace_mm_collapse_huge_page_swapin(mm, swapped_in, 0); + return; + } + /* pte is unmapped now, we need to map it */ + pte = pte_offset_map(pmd, _address); + } + pte--; + pte_unmap(pte); + trace_mm_collapse_huge_page_swapin(mm, swapped_in, 1); +} + static void collapse_huge_page(struct mm_struct *mm, unsigned long address, struct page **hpage, @@ -2440,6 +2478,8 @@ static void collapse_huge_page(struct mm_struct *mm, goto out; } + __collapse_huge_page_swapin(mm, vma, address, pmd); + anon_vma_lock_write(vma->anon_vma); pte = pte_offset_map(pmd, address); @@ -2516,9 +2556,6 @@ static void collapse_huge_page(struct mm_struct *mm, result = SCAN_SUCCEED; out_up_write: up_write(&mm->mmap_sem); - trace_mm_collapse_huge_page(mm, isolated, result); - return; - out_nolock: trace_mm_collapse_huge_page(mm, isolated, result); return; diff --git a/mm/internal.h b/mm/internal.h index fbfba0cc2c35..e1531758122b 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -36,6 +36,10 @@ /* Do not use these with a slab allocator */ #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK) +extern int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma, + unsigned long address, pte_t *page_table, pmd_t *pmd, + unsigned int flags, pte_t orig_pte); + void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma, unsigned long floor, unsigned long ceiling); diff --git a/mm/memory.c b/mm/memory.c index a329149e1c54..5e6eadd127e7 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2522,7 +2522,7 @@ EXPORT_SYMBOL(unmap_mapping_range); * We return with the mmap_sem locked or unlocked in the same cases * as does filemap_fault(). */ -static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma, +int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long address, pte_t *page_table, pmd_t *pmd, unsigned int flags, pte_t orig_pte) { |