From: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
The same fallback path will be reused by non-anonymous pages, so lets'
extract it in separate function.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
---
mm/huge_memory.c | 112 ++++++++++++++++++++++++++++--------------------------
1 file changed, 59 insertions(+), 53 deletions(-)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index be7b7e1..0df1309 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -779,64 +779,12 @@ static bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
return true;
}
-int do_huge_pmd_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
+static int do_fallback(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, pmd_t *pmd,
unsigned int flags)
{
- struct page *page;
- unsigned long haddr = address & HPAGE_PMD_MASK;
pte_t *pte;
- if (haddr >= vma->vm_start && haddr + HPAGE_PMD_SIZE <= vma->vm_end) {
- if (unlikely(anon_vma_prepare(vma)))
- return VM_FAULT_OOM;
- if (unlikely(khugepaged_enter(vma)))
- return VM_FAULT_OOM;
- if (!(flags & FAULT_FLAG_WRITE) &&
- transparent_hugepage_use_zero_page()) {
- pgtable_t pgtable;
- unsigned long zero_pfn;
- bool set;
- pgtable = pte_alloc_one(mm, haddr);
- if (unlikely(!pgtable))
- return VM_FAULT_OOM;
- zero_pfn = get_huge_zero_page();
- if (unlikely(!zero_pfn)) {
- pte_free(mm, pgtable);
- count_vm_event(THP_FAULT_FALLBACK);
- goto out;
- }
- spin_lock(&mm->page_table_lock);
- set = set_huge_zero_page(pgtable, mm, vma, haddr, pmd,
- zero_pfn);
- spin_unlock(&mm->page_table_lock);
- if (!set) {
- pte_free(mm, pgtable);
- put_huge_zero_page();
- }
- return 0;
- }
- page = alloc_hugepage_vma(transparent_hugepage_defrag(vma),
- vma, haddr, numa_node_id(), 0);
- if (unlikely(!page)) {
- count_vm_event(THP_FAULT_FALLBACK);
- goto out;
- }
- count_vm_event(THP_FAULT_ALLOC);
- if (unlikely(mem_cgroup_newpage_charge(page, mm, GFP_KERNEL))) {
- put_page(page);
- goto out;
- }
- if (unlikely(__do_huge_pmd_anonymous_page(mm, vma, haddr, pmd,
- page))) {
- mem_cgroup_uncharge_page(page);
- put_page(page);
- goto out;
- }
-
- return 0;
- }
-out:
/*
* Use __pte_alloc instead of pte_alloc_map, because we can't
* run pte_offset_map on the pmd, if an huge pmd could
@@ -858,6 +806,64 @@ out:
return handle_pte_fault(mm, vma, address, pte, pmd, flags);
}
+int do_huge_pmd_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
+ unsigned long address, pmd_t *pmd,
+ unsigned int flags)
+{
+ struct page *page;
+ unsigned long haddr = address & HPAGE_PMD_MASK;
+
+ if (haddr < vma->vm_start || haddr + HPAGE_PMD_SIZE > vma->vm_end)
+ return do_fallback(mm, vma, address, pmd, flags);
+ if (unlikely(anon_vma_prepare(vma)))
+ return VM_FAULT_OOM;
+ if (unlikely(khugepaged_enter(vma)))
+ return VM_FAULT_OOM;
+ if (!(flags & FAULT_FLAG_WRITE) &&
+ transparent_hugepage_use_zero_page()) {
+ pgtable_t pgtable;
+ unsigned long zero_pfn;
+ bool set;
+ pgtable = pte_alloc_one(mm, haddr);
+ if (unlikely(!pgtable))
+ return VM_FAULT_OOM;
+ zero_pfn = get_huge_zero_page();
+ if (unlikely(!zero_pfn)) {
+ pte_free(mm, pgtable);
+ count_vm_event(THP_FAULT_FALLBACK);
+ return do_fallback(mm, vma, address, pmd, flags);
+ }
+ spin_lock(&mm->page_table_lock);
+ set = set_huge_zero_page(pgtable, mm, vma, haddr, pmd,
+ zero_pfn);
+ spin_unlock(&mm->page_table_lock);
+ if (!set) {
+ pte_free(mm, pgtable);
+ put_huge_zero_page();
+ }
+ return 0;
+ }
+ page = alloc_hugepage_vma(transparent_hugepage_defrag(vma),
+ vma, haddr, numa_node_id(), 0);
+ if (unlikely(!page)) {
+ count_vm_event(THP_FAULT_FALLBACK);
+ return do_fallback(mm, vma, address, pmd, flags);
+ }
+ count_vm_event(THP_FAULT_ALLOC);
+ if (unlikely(mem_cgroup_newpage_charge(page, mm, GFP_KERNEL))) {
+ put_page(page);
+ return do_fallback(mm, vma, address, pmd, flags);
+ }
+ if (unlikely(__do_huge_pmd_anonymous_page(mm, vma, haddr, pmd,
+ page))) {
+ mem_cgroup_uncharge_page(page);
+ put_page(page);
+ return do_fallback(mm, vma, address, pmd, flags);
+ }
+
+ return 0;
+}
+
int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
struct vm_area_struct *vma)
--
1.7.10.4
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