[PATCH 4.9 01/50] mm/huge_memory: rename freeze_page() to unmap_page()

From: Greg Kroah-Hartman
Date: Tue Dec 04 2018 - 06:13:28 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

commit 906f9cdfc2a0800f13683f9e4ebdfd08c12ee81b upstream.

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.

Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1811261514080.2275@xxxxxxxxxxxx
Fixes: e9b61f19858a5 ("thp: reintroduce split_huge_page()")
Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx>
Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Jerome Glisse <jglisse@xxxxxxxxxx>
Cc: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> [4.8+]
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
mm/huge_memory.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 9f7bba700e4e..583ad61cc2f1 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1839,7 +1839,7 @@ 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 |
TTU_RMAP_LOCKED;
@@ -1862,7 +1862,7 @@ static void freeze_page(struct page *page)
VM_BUG_ON_PAGE(ret, page + i - 1);
}

-static void unfreeze_page(struct page *page)
+static void remap_page(struct page *page)
{
int i;

@@ -1971,7 +1971,7 @@ static void __split_huge_page(struct page *page, struct list_head *list,

spin_unlock_irqrestore(zone_lru_lock(page_zone(head)), flags);

- unfreeze_page(head);
+ remap_page(head);

for (i = 0; i < HPAGE_PMD_NR; i++) {
struct page *subpage = head + i;
@@ -2138,7 +2138,7 @@ 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 (total_mapcount(head) != page_count(head) - extra_pins - 1) {
@@ -2147,7 +2147,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
}

mlocked = PageMlocked(page);
- freeze_page(head);
+ unmap_page(head);
VM_BUG_ON_PAGE(compound_mapcount(head), head);

/* Make sure the page is not on per-CPU pagevec as it takes pin */
@@ -2199,7 +2199,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
fail: if (mapping)
spin_unlock(&mapping->tree_lock);
spin_unlock_irqrestore(zone_lru_lock(page_zone(head)), flags);
- unfreeze_page(head);
+ remap_page(head);
ret = -EBUSY;
}

--
2.17.1