summaryrefslogtreecommitdiff
path: root/mm
diff options
context:
space:
mode:
authorDavid Hildenbrand <david@redhat.com>2023-08-21 19:08:49 +0300
committerAndrew Morton <akpm@linux-foundation.org>2023-08-25 02:20:28 +0300
commit07e09c483cbef2a252f75d95670755a0607288f5 (patch)
tree15f38d9a549e22aef6bd9a270ace05a7aa5c7f6d /mm
parent3d2c908768877714a354ee6d7bf93e801400d5e2 (diff)
downloadlinux-07e09c483cbef2a252f75d95670755a0607288f5.tar.xz
mm/huge_memory: work on folio->swap instead of page->private when splitting folio
Let's work on folio->swap instead. While at it, use folio_test_anon() and folio_test_swapcache() -- the original folio remains valid even after splitting (but is then an order-0 folio). We can probably convert a lot more to folios in that code, let's focus on folio->swap handling only for now. Link: https://lkml.kernel.org/r/20230821160849.531668-5-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Chris Li <chrisl@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dan Streetman <ddstreet@ieee.org> Cc: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Seth Jennings <sjenning@redhat.com> Cc: Vitaly Wool <vitaly.wool@konsulko.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm')
-rw-r--r--mm/huge_memory.c29
1 files changed, 15 insertions, 14 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index a28e9fe16585..c4635f750255 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2401,10 +2401,16 @@ static void lru_add_page_tail(struct page *head, struct page *tail,
}
}
-static void __split_huge_page_tail(struct page *head, int tail,
+static void __split_huge_page_tail(struct folio *folio, int tail,
struct lruvec *lruvec, struct list_head *list)
{
+ struct page *head = &folio->page;
struct page *page_tail = head + tail;
+ /*
+ * Careful: new_folio is not a "real" folio before we cleared PageTail.
+ * Don't pass it around before clear_compound_head().
+ */
+ struct folio *new_folio = (struct folio *)page_tail;
VM_BUG_ON_PAGE(atomic_read(&page_tail->_mapcount) != -1, page_tail);
@@ -2453,8 +2459,8 @@ static void __split_huge_page_tail(struct page *head, int tail,
VM_WARN_ON_ONCE_PAGE(true, page_tail);
page_tail->private = 0;
}
- if (PageSwapCache(head))
- set_page_private(page_tail, (unsigned long)head->private + tail);
+ if (folio_test_swapcache(folio))
+ new_folio->swap.val = folio->swap.val + tail;
/* Page flags must be visible before we make the page non-compound. */
smp_wmb();
@@ -2500,11 +2506,9 @@ static void __split_huge_page(struct page *page, struct list_head *list,
/* complete memcg works before add pages to LRU */
split_page_memcg(head, nr);
- if (PageAnon(head) && PageSwapCache(head)) {
- swp_entry_t entry = { .val = page_private(head) };
-
- offset = swp_offset(entry);
- swap_cache = swap_address_space(entry);
+ if (folio_test_anon(folio) && folio_test_swapcache(folio)) {
+ offset = swp_offset(folio->swap);
+ swap_cache = swap_address_space(folio->swap);
xa_lock(&swap_cache->i_pages);
}
@@ -2514,7 +2518,7 @@ static void __split_huge_page(struct page *page, struct list_head *list,
ClearPageHasHWPoisoned(head);
for (i = nr - 1; i >= 1; i--) {
- __split_huge_page_tail(head, i, lruvec, list);
+ __split_huge_page_tail(folio, i, lruvec, list);
/* Some pages can be beyond EOF: drop them from page cache */
if (head[i].index >= end) {
struct folio *tail = page_folio(head + i);
@@ -2559,11 +2563,8 @@ static void __split_huge_page(struct page *page, struct list_head *list,
remap_page(folio, nr);
- if (PageSwapCache(head)) {
- swp_entry_t entry = { .val = page_private(head) };
-
- split_swap_cluster(entry);
- }
+ if (folio_test_swapcache(folio))
+ split_swap_cluster(folio->swap);
for (i = 0; i < nr; i++) {
struct page *subpage = head + i;