[PATCH v4 1/4] mm: zswap: zswap_is_folio_same_filled() takes an index in the folio.
From: Kanchana P Sridhar
Date: Sun Aug 18 2024 - 22:16:36 EST
This change is being made so that zswap_store can process mTHP folios.
Modified zswap_is_folio_same_filled() to work for any-order folios,
by accepting an additional "index" parameter to arrive at the
page within the folio to run the same-filled page check.
Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@xxxxxxxxx>
---
mm/zswap.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/mm/zswap.c b/mm/zswap.c
index df66ab102d27..6434e76a4ea3 100644
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -1419,14 +1419,14 @@ static void shrink_worker(struct work_struct *w)
/*********************************
* same-filled functions
**********************************/
-static bool zswap_is_folio_same_filled(struct folio *folio, unsigned long *value)
+static bool zswap_is_folio_same_filled(struct folio *folio, long index, unsigned long *value)
{
unsigned long *data;
unsigned long val;
unsigned int pos, last_pos = PAGE_SIZE / sizeof(*data) - 1;
bool ret = false;
- data = kmap_local_folio(folio, 0);
+ data = kmap_local_folio(folio, index * PAGE_SIZE);
val = data[0];
if (val != data[last_pos])
@@ -1496,7 +1496,7 @@ bool zswap_store(struct folio *folio)
goto reject;
}
- if (zswap_is_folio_same_filled(folio, &value)) {
+ if (zswap_is_folio_same_filled(folio, 0, &value)) {
entry->length = 0;
entry->value = value;
atomic_inc(&zswap_same_filled_pages);
--
2.27.0