[PATCH v2 4/6] mm: kmem: switch to nr_pages in (__)memcg_kmem_charge_memcg()

Roman Gushchin
2020-01-09T20:27:17Z

These functions are charging the given number of kernel pages to the
given memory cgroup. The number doesn't have to be a power of two.
Let's make them to take the unsigned int nr_pages as an argument
instead of the page order.

It makes them look consistent with the corresponding uncharge
functions and functions like: mem_cgroup_charge_skmem(memcg, nr_pages).

Signed-off-by: Roman Gushchin <guro@fb.com>
---
include/linux/memcontrol.h | 11 ++++++-----
mm/memcontrol.c | 8 ++++----
mm/slab.h | 2 +-
3 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 4ee0c345e905..851c373edb74 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -1364,7 +1364,8 @@ void memcg_kmem_put_cache(struct kmem_cache *cachep);
#ifdef CONFIG_MEMCG_KMEM
int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order);
void __memcg_kmem_uncharge_page(struct page *page, int order);
-int __memcg_kmem_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp, int order);
+int __memcg_kmem_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp,
+ unsigned int nr_pages);
void __memcg_kmem_uncharge_memcg(struct mem_cgroup *memcg,
unsigned int nr_pages);

@@ -1403,18 +1404,18 @@ static inline void memcg_kmem_uncharge_page(struct page *page, int order)
}

static inline int memcg_kmem_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp,
- int order)
+ unsigned int nr_pages)
{
if (memcg_kmem_enabled())
- return __memcg_kmem_charge_memcg(memcg, gfp, order);
+ return __memcg_kmem_charge_memcg(memcg, gfp, nr_pages);
return 0;
}

static inline void memcg_kmem_uncharge_memcg(struct mem_cgroup *memcg,
- int order)
+ unsigned int nr_pages)
{
if (memcg_kmem_enabled())
- __memcg_kmem_uncharge_memcg(memcg, 1 << order);
+ __memcg_kmem_uncharge_memcg(memcg, nr_pages);
}

/*
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 6bdf040e4615..8dbfb9fed9d8 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2822,13 +2822,13 @@ void memcg_kmem_put_cache(struct kmem_cache *cachep)
* __memcg_kmem_charge_memcg: charge a kmem page
* @memcg: memory cgroup to charge
* @gfp: reclaim mode
- * @order: allocation order
+ * @nr_pages: number of pages to charge
*
* Returns 0 on success, an error code on failure.
*/
-int __memcg_kmem_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp, int order)
+int __memcg_kmem_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp,
+ unsigned int nr_pages)
{
- unsigned int nr_pages = 1 << order;
struct page_counter *counter;
int ret;

@@ -2872,7 +2872,7 @@ int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order)

memcg = get_mem_cgroup_from_current();
if (!mem_cgroup_is_root(memcg)) {
- ret = __memcg_kmem_charge_memcg(memcg, gfp, order);
+ ret = __memcg_kmem_charge_memcg(memcg, gfp, 1 << order);
if (!ret) {
page->mem_cgroup = memcg;
__SetPageKmemcg(page);
diff --git a/mm/slab.h b/mm/slab.h
index e7da63fb8211..d96c87a30a9b 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -365,7 +365,7 @@ static __always_inline int memcg_charge_slab(struct page *page,
return 0;
}

- ret = memcg_kmem_charge_memcg(memcg, gfp, order);
+ ret = memcg_kmem_charge_memcg(memcg, gfp, 1 << order);
if (ret)
goto out;

--
2.21.1