[PATCH 02/15] mm/z3fold: use zpdesc in z3fold_page_migrate

alexs
2024-06-21T05:42:16Z

Convert page to zpdesc in z3fold_page_migrate. And introduce
zpdesc_get/put base on folio_get/put helpers, since z3fold only
deal with single pages.

This patch could save about 12Kbytes.

Signed-off-by: Alex Shi <alexs@kernel.org>
---
mm/z3fold.c | 30 ++++++++++++++++--------------
mm/zpdesc.h | 10 ++++++++++
2 files changed, 26 insertions(+), 14 deletions(-)

diff --git a/mm/z3fold.c b/mm/z3fold.c
index b1229c0520f1..b7f86c1b57a3 100644
--- a/mm/z3fold.c
+++ b/mm/z3fold.c
@@ -1290,18 +1290,20 @@ static int z3fold_page_migrate(struct page *newpage, struct page *page,
{
struct z3fold_header *zhdr, *new_zhdr;
struct z3fold_pool *pool;
+ struct zpdesc *zpdesc = page_zpdesc(page);
+ struct zpdesc *newzpdesc = page_zpdesc(newpage);

- VM_BUG_ON_PAGE(!PageIsolated(page), page);
- VM_BUG_ON_PAGE(!test_bit(PAGE_CLAIMED, &page->private), page);
- VM_BUG_ON_PAGE(!PageLocked(newpage), newpage);
+ VM_BUG_ON_PAGE(!PageIsolated(zpdesc_page(zpdesc)), zpdesc_page(zpdesc));
+ VM_BUG_ON_PAGE(!test_bit(PAGE_CLAIMED, &zpdesc->zppage_flag), zpdesc_page(zpdesc));
+ VM_BUG_ON_PAGE(!PageLocked(zpdesc_page(newzpdesc)), zpdesc_page(newzpdesc));

- zhdr = page_address(page);
+ zhdr = zpdesc_address(zpdesc);
pool = zhdr_to_pool(zhdr);

if (!z3fold_page_trylock(zhdr))
return -EAGAIN;
if (zhdr->mapped_count != 0 || zhdr->foreign_handles != 0) {
- clear_bit(PAGE_CLAIMED, &page->private);
+ clear_bit(PAGE_CLAIMED, &zpdesc->zppage_flag);
z3fold_page_unlock(zhdr);
return -EBUSY;
}
@@ -1309,10 +1311,10 @@ static int z3fold_page_migrate(struct page *newpage, struct page *page,
z3fold_page_unlock(zhdr);
return -EAGAIN;
}
- new_zhdr = page_address(newpage);
+ new_zhdr = zpdesc_address(newzpdesc);
memcpy(new_zhdr, zhdr, PAGE_SIZE);
- newpage->private = page->private;
- set_bit(PAGE_MIGRATED, &page->private);
+ newzpdesc->zppage_flag = zpdesc->zppage_flag;
+ set_bit(PAGE_MIGRATED, &zpdesc->zppage_flag);
z3fold_page_unlock(zhdr);
spin_lock_init(&new_zhdr->page_lock);
INIT_WORK(&new_zhdr->work, compact_page_work);
@@ -1321,9 +1323,9 @@ static int z3fold_page_migrate(struct page *newpage, struct page *page,
* so we only have to reinitialize it.
*/
INIT_LIST_HEAD(&new_zhdr->buddy);
- __ClearPageMovable(page);
+ __ClearPageMovable(zpdesc_page(zpdesc));

- get_page(newpage);
+ zpdesc_get(newzpdesc);
z3fold_page_lock(new_zhdr);
if (new_zhdr->first_chunks)
encode_handle(new_zhdr, FIRST);
@@ -1331,16 +1333,16 @@ static int z3fold_page_migrate(struct page *newpage, struct page *page,
encode_handle(new_zhdr, LAST);
if (new_zhdr->middle_chunks)
encode_handle(new_zhdr, MIDDLE);
- set_bit(NEEDS_COMPACTING, &newpage->private);
+ set_bit(NEEDS_COMPACTING, &newzpdesc->zppage_flag);
new_zhdr->cpu = smp_processor_id();
- __SetPageMovable(newpage, &z3fold_mops);
+ __SetPageMovable(zpdesc_page(newzpdesc), &z3fold_mops);
z3fold_page_unlock(new_zhdr);

queue_work_on(new_zhdr->cpu, pool->compact_wq, &new_zhdr->work);

/* PAGE_CLAIMED and PAGE_MIGRATED are cleared now. */
- page->private = 0;
- put_page(page);
+ zpdesc->zppage_flag = 0;
+ zpdesc_put(zpdesc);
return 0;
}

diff --git a/mm/zpdesc.h b/mm/zpdesc.h
index d51785863596..7fde29645331 100644
--- a/mm/zpdesc.h
+++ b/mm/zpdesc.h
@@ -48,4 +48,14 @@ static inline void *zpdesc_address(const struct zpdesc *zpdesc)
return folio_address(zpdesc_folio(zpdesc));
}

+static inline void zpdesc_get(struct zpdesc *zpdesc)
+{
+ folio_get(zpdesc_folio(zpdesc));
+}
+
+static inline void zpdesc_put(struct zpdesc *zpdesc)
+{
+ folio_put(zpdesc_folio(zpdesc));
+}
+
#endif
--
2.43.0