From: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
The base scheme is the same as for anonymous pages, but we walk by
mapping->i_mmap rather then anon_vma->rb_root.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
---
mm/huge_memory.c | 68 +++++++++++++++++++++++++++++++++++++++++++++---------
1 file changed, 57 insertions(+), 11 deletions(-)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index ed31e90..73974e8 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1655,23 +1655,23 @@ static void __split_huge_page_refcount(struct page *page,
*/
page_tail->_mapcount = page->_mapcount;
- BUG_ON(page_tail->mapping);
page_tail->mapping = page->mapping;
page_tail->index = page->index + i;
page_nid_xchg_last(page_tail, page_nid_last(page));
- BUG_ON(!PageAnon(page_tail));
BUG_ON(!PageUptodate(page_tail));
BUG_ON(!PageDirty(page_tail));
- BUG_ON(!PageSwapBacked(page_tail));
lru_add_page_tail(page, page_tail, lruvec, list);
}
atomic_sub(tail_count, &page->_count);
BUG_ON(atomic_read(&page->_count) <= 0);
- __mod_zone_page_state(zone, NR_ANON_TRANSPARENT_HUGEPAGES, -1);
+ if (PageAnon(page))
+ __mod_zone_page_state(zone, NR_ANON_TRANSPARENT_HUGEPAGES, -1);
+ else
+ __mod_zone_page_state(zone, NR_FILE_TRANSPARENT_HUGEPAGES, -1);
ClearPageCompound(page);
compound_unlock(page);
@@ -1771,7 +1771,7 @@ static int __split_huge_page_map(struct page *page,
}
/* must be called with anon_vma->root->rwsem held */
-static void __split_huge_page(struct page *page,
+static void __split_anon_huge_page(struct page *page,
struct anon_vma *anon_vma,
struct list_head *list)
{
@@ -1795,7 +1795,7 @@ static void __split_huge_page(struct page *page,
* and establishes a child pmd before
* __split_huge_page_splitting() freezes the parent pmd (so if
* we fail to prevent copy_huge_pmd() from running until the
- * whole __split_huge_page() is complete), we will still see
+ * whole __split_anon_huge_page() is complete), we will still see
* the newly established pmd of the child later during the
* walk, to be able to set it as pmd_trans_splitting too.
*/
@@ -1826,14 +1826,11 @@ static void __split_huge_page(struct page *page,
* from the hugepage.
* Return 0 if the hugepage is split successfully otherwise return 1.
*/
-int split_huge_page_to_list(struct page *page, struct list_head *list)
+static int split_anon_huge_page(struct page *page, struct list_head *list)
{
struct anon_vma *anon_vma;
int ret = 1;
- BUG_ON(is_huge_zero_page(page));
- BUG_ON(!PageAnon(page));
-
/*
* The caller does not necessarily hold an mmap_sem that would prevent
* the anon_vma disappearing so we first we take a reference to it
@@ -1851,7 +1848,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
goto out_unlock;
BUG_ON(!PageSwapBacked(page));
- __split_huge_page(page, anon_vma, list);
+ __split_anon_huge_page(page, anon_vma, list);
count_vm_event(THP_SPLIT);
BUG_ON(PageCompound(page));
@@ -1862,6 +1859,55 @@ out:
return ret;
}
+static int split_file_huge_page(struct page *page, struct list_head *list)
+{
+ struct address_space *mapping = page->mapping;
+ pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
+ struct vm_area_struct *vma;
+ int mapcount, mapcount2;
+
+ BUG_ON(!PageHead(page));
+ BUG_ON(PageTail(page));
+
+ mutex_lock(&mapping->i_mmap_mutex);
+ mapcount = 0;
+ vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) {
+ unsigned long addr = vma_address(page, vma);
+ mapcount += __split_huge_page_splitting(page, vma, addr);
+ }
+
+ if (mapcount != page_mapcount(page))
+ printk(KERN_ERR "mapcount %d page_mapcount %d\n",
+ mapcount, page_mapcount(page));
+ BUG_ON(mapcount != page_mapcount(page));
+
+ __split_huge_page_refcount(page, list);
+
+ mapcount2 = 0;
+ vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) {
+ unsigned long addr = vma_address(page, vma);
+ mapcount2 += __split_huge_page_map(page, vma, addr);
+ }
+
+ if (mapcount != mapcount2)
+ printk(KERN_ERR "mapcount %d mapcount2 %d page_mapcount %d\n",
+ mapcount, mapcount2, page_mapcount(page));
+ BUG_ON(mapcount != mapcount2);
+ count_vm_event(THP_SPLIT);
+ mutex_unlock(&mapping->i_mmap_mutex);
+ return 0;
+}
+
+int split_huge_page_to_list(struct page *page, struct list_head *list)
+{
+ BUG_ON(is_huge_zero_page(page));
+
+ if (PageAnon(page))
+ return split_anon_huge_page(page, list);
+ else
+ return split_file_huge_page(page, list);
+}
+
#define VM_NO_THP (VM_SPECIAL|VM_MIXEDMAP|VM_HUGETLB|VM_SHARED|VM_MAYSHARE)
int hugepage_madvise(struct vm_area_struct *vma,
--
1.7.10.4
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>