Commit 906f9cdf authored by Hugh Dickins's avatar Hugh Dickins Committed by Linus Torvalds

mm/huge_memory: rename freeze_page() to unmap_page()

The term "freeze" is used in several ways in the kernel, and in mm it
has the particular meaning of forcing page refcount temporarily to 0.
freeze_page() is just too confusing a name for a function that unmaps a
page: rename it unmap_page(), and rename unfreeze_page() remap_page().

Went to change the mention of freeze_page() added later in mm/rmap.c,
but found it to be incorrect: ordinary page reclaim reaches there too;
but the substance of the comment still seems correct, so edit it down.

Fixes: e9b61f19 ("thp: reintroduce split_huge_page()")
Signed-off-by: default avatarHugh Dickins <>
Acked-by: default avatarKirill A. Shutemov <>
Cc: Jerome Glisse <>
Cc: Konstantin Khlebnikov <>
Cc: Matthew Wilcox <>
Cc: <>	[4.8+]
Signed-off-by: default avatarAndrew Morton <>
Signed-off-by: default avatarLinus Torvalds <>
parent 7c0950d4
......@@ -2350,7 +2350,7 @@ void vma_adjust_trans_huge(struct vm_area_struct *vma,
static void freeze_page(struct page *page)
static void unmap_page(struct page *page)
enum ttu_flags ttu_flags = TTU_IGNORE_MLOCK | TTU_IGNORE_ACCESS |
......@@ -2365,7 +2365,7 @@ static void freeze_page(struct page *page)
VM_BUG_ON_PAGE(!unmap_success, page);
static void unfreeze_page(struct page *page)
static void remap_page(struct page *page)
int i;
if (PageTransHuge(page)) {
......@@ -2483,7 +2483,7 @@ static void __split_huge_page(struct page *page, struct list_head *list,
spin_unlock_irqrestore(zone_lru_lock(page_zone(head)), flags);
for (i = 0; i < HPAGE_PMD_NR; i++) {
struct page *subpage = head + i;
......@@ -2664,7 +2664,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
* Racy check if we can split the page, before freeze_page() will
* Racy check if we can split the page, before unmap_page() will
* split PMDs
if (!can_split_huge_page(head, &extra_pins)) {
......@@ -2673,7 +2673,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
mlocked = PageMlocked(page);
VM_BUG_ON_PAGE(compound_mapcount(head), head);
/* Make sure the page is not on per-CPU pagevec as it takes pin */
......@@ -2727,7 +2727,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
fail: if (mapping)
spin_unlock_irqrestore(zone_lru_lock(page_zone(head)), flags);
ret = -EBUSY;
......@@ -1627,16 +1627,9 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
address + PAGE_SIZE);
} else {
* We should not need to notify here as we reach this
* case only from freeze_page() itself only call from
* split_huge_page_to_list() so everything below must
* be true:
* - page is not anonymous
* - page is locked
* So as it is a locked file back page thus it can not
* be remove from the page cache and replace by a new
* page before mmu_notifier_invalidate_range_end so no
* This is a locked file-backed page, thus it cannot
* be removed from the page cache and replaced by a new
* page before mmu_notifier_invalidate_range_end, so no
* concurrent thread might update its page table to
* point at new page while a device still is using this
* page.
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