[PATCH 3/5] memcg: Convert get_obj_cgroup_from_page to get_obj_cgroup_from_folio

From: Matthew Wilcox (Oracle)
Date: Sat Jul 15 2023 - 00:24:08 EST


As the one caller now has a folio, pass it in and use it. Removes three
calls to compound_head().

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
include/linux/memcontrol.h | 4 ++--
mm/memcontrol.c | 8 ++++----
mm/zswap.c | 2 +-
3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 5818af8eca5a..7b676752f474 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -1761,7 +1761,7 @@ int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order);
void __memcg_kmem_uncharge_page(struct page *page, int order);

struct obj_cgroup *get_obj_cgroup_from_current(void);
-struct obj_cgroup *get_obj_cgroup_from_page(struct page *page);
+struct obj_cgroup *get_obj_cgroup_from_folio(struct folio *folio);

int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size);
void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size);
@@ -1845,7 +1845,7 @@ static inline void __memcg_kmem_uncharge_page(struct page *page, int order)
{
}

-static inline struct obj_cgroup *get_obj_cgroup_from_page(struct page *page)
+static inline struct obj_cgroup *get_obj_cgroup_from_folio(struct folio *folio)
{
return NULL;
}
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index e8ca4bdcb03c..acc9acb0c9a1 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3036,21 +3036,21 @@ __always_inline struct obj_cgroup *get_obj_cgroup_from_current(void)
return objcg;
}

-struct obj_cgroup *get_obj_cgroup_from_page(struct page *page)
+struct obj_cgroup *get_obj_cgroup_from_folio(struct folio *folio)
{
struct obj_cgroup *objcg;

if (!memcg_kmem_online())
return NULL;

- if (PageMemcgKmem(page)) {
- objcg = __folio_objcg(page_folio(page));
+ if (folio_memcg_kmem(folio)) {
+ objcg = __folio_objcg(folio);
obj_cgroup_get(objcg);
} else {
struct mem_cgroup *memcg;

rcu_read_lock();
- memcg = __folio_memcg(page_folio(page));
+ memcg = __folio_memcg(folio);
if (memcg)
objcg = __get_obj_cgroup_from_memcg(memcg);
else
diff --git a/mm/zswap.c b/mm/zswap.c
index ba50b186ee27..69d097d14255 100644
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -1235,7 +1235,7 @@ bool zswap_store(struct folio *folio)
* cgroup-aware entry LRU, we will push out entries system-wide based on
* local cgroup limits.
*/
- objcg = get_obj_cgroup_from_page(page);
+ objcg = get_obj_cgroup_from_folio(folio);
if (objcg && !obj_cgroup_may_zswap(objcg))
goto reject;

--
2.39.2