[PATCH v2 3/6] mm: kmem: rename memcg_kmem_(un)charge() into memcg_kmem_(un)charge_page()

Roman Gushchin
2020-01-09T20:27:20Z

Rename (__)memcg_kmem_(un)charge() into (__)memcg_kmem_(un)charge_page()
to better reflect what they are actually doing:
1) call __memcg_kmem_(un)charge_memcg() to actually charge or
uncharge the current memcg
2) set or clear the PageKmemcg flag

Signed-off-by: Roman Gushchin <guro@fb.com>
---
fs/pipe.c | 2 +-
include/linux/memcontrol.h | 23 +++++++++++++----------
kernel/fork.c | 9 +++++----
mm/memcontrol.c | 8 ++++----
mm/page_alloc.c | 4 ++--
5 files changed, 25 insertions(+), 21 deletions(-)

diff --git a/fs/pipe.c b/fs/pipe.c
index 57502c3c0fba..f1851f7ecbd6 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -143,7 +143,7 @@ static int anon_pipe_buf_steal(struct pipe_inode_info *pipe,
struct page *page = buf->page;

if (page_count(page) == 1) {
- memcg_kmem_uncharge(page, 0);
+ memcg_kmem_uncharge_page(page, 0);
__SetPageLocked(page);
return 0;
}
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 900a9f884260..4ee0c345e905 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -1362,8 +1362,8 @@ struct kmem_cache *memcg_kmem_get_cache(struct kmem_cache *cachep);
void memcg_kmem_put_cache(struct kmem_cache *cachep);

#ifdef CONFIG_MEMCG_KMEM
-int __memcg_kmem_charge(struct page *page, gfp_t gfp, int order);
-void __memcg_kmem_uncharge(struct page *page, int order);
+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);
void __memcg_kmem_uncharge_memcg(struct mem_cgroup *memcg,
unsigned int nr_pages);
@@ -1388,17 +1388,18 @@ static inline bool memcg_kmem_enabled(void)
return static_branch_unlikely(&memcg_kmem_enabled_key);
}

-static inline int memcg_kmem_charge(struct page *page, gfp_t gfp, int order)
+static inline int memcg_kmem_charge_page(struct page *page, gfp_t gfp,
+ int order)
{
if (memcg_kmem_enabled())
- return __memcg_kmem_charge(page, gfp, order);
+ return __memcg_kmem_charge_page(page, gfp, order);
return 0;
}

-static inline void memcg_kmem_uncharge(struct page *page, int order)
+static inline void memcg_kmem_uncharge_page(struct page *page, int order)
{
if (memcg_kmem_enabled())
- __memcg_kmem_uncharge(page, order);
+ __memcg_kmem_uncharge_page(page, order);
}

static inline int memcg_kmem_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp,
@@ -1428,21 +1429,23 @@ static inline int memcg_cache_id(struct mem_cgroup *memcg)

#else

-static inline int memcg_kmem_charge(struct page *page, gfp_t gfp, int order)
+static inline int memcg_kmem_charge_page(struct page *page, gfp_t gfp,
+ int order)
{
return 0;
}

-static inline void memcg_kmem_uncharge(struct page *page, int order)
+static inline void memcg_kmem_uncharge_page(struct page *page, int order)
{
}

-static inline int __memcg_kmem_charge(struct page *page, gfp_t gfp, int order)
+static inline int __memcg_kmem_charge_page(struct page *page, gfp_t gfp,
+ int order)
{
return 0;
}

-static inline void __memcg_kmem_uncharge(struct page *page, int order)
+static inline void __memcg_kmem_uncharge_page(struct page *page, int order)
{
}

diff --git a/kernel/fork.c b/kernel/fork.c
index 2508a4f238a3..6e410a189683 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -281,7 +281,7 @@ static inline void free_thread_stack(struct task_struct *tsk)
MEMCG_KERNEL_STACK_KB,
-(int)(PAGE_SIZE / 1024));

- memcg_kmem_uncharge(vm->pages[i], 0);
+ memcg_kmem_uncharge_page(vm->pages[i], 0);
}

for (i = 0; i < NR_CACHED_STACKS; i++) {
@@ -413,12 +413,13 @@ static int memcg_charge_kernel_stack(struct task_struct *tsk)

for (i = 0; i < THREAD_SIZE / PAGE_SIZE; i++) {
/*
- * If memcg_kmem_charge() fails, page->mem_cgroup
- * pointer is NULL, and both memcg_kmem_uncharge()
+ * If memcg_kmem_charge_page() fails, page->mem_cgroup
+ * pointer is NULL, and both memcg_kmem_uncharge_page()
* and mod_memcg_page_state() in free_thread_stack()
* will ignore this page. So it's safe.
*/
- ret = memcg_kmem_charge(vm->pages[i], GFP_KERNEL, 0);
+ ret = memcg_kmem_charge_page(vm->pages[i], GFP_KERNEL,
+ 0);
if (ret)
return ret;

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 6ef38f669923..6bdf040e4615 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2855,14 +2855,14 @@ int __memcg_kmem_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp, int order)
}

/**
- * __memcg_kmem_charge: charge a kmem page to the current memory cgroup
+ * __memcg_kmem_charge_page: charge a kmem page to the current memory cgroup
* @page: page to charge
* @gfp: reclaim mode
* @order: allocation order
*
* Returns 0 on success, an error code on failure.
*/
-int __memcg_kmem_charge(struct page *page, gfp_t gfp, int order)
+int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order)
{
struct mem_cgroup *memcg;
int ret = 0;
@@ -2898,11 +2898,11 @@ void __memcg_kmem_uncharge_memcg(struct mem_cgroup *memcg,
page_counter_uncharge(&memcg->memsw, nr_pages);
}
/**
- * __memcg_kmem_uncharge: uncharge a kmem page
+ * __memcg_kmem_uncharge_page: uncharge a kmem page
* @page: page to uncharge
* @order: allocation order
*/
-void __memcg_kmem_uncharge(struct page *page, int order)
+void __memcg_kmem_uncharge_page(struct page *page, int order)
{
struct mem_cgroup *memcg = page->mem_cgroup;
unsigned int nr_pages = 1 << order;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 4785a8a2040e..8fca5b806139 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1159,7 +1159,7 @@ static __always_inline bool free_pages_prepare(struct page *page,
if (PageMappingFlags(page))
page->mapping = NULL;
if (memcg_kmem_enabled() && PageKmemcg(page))
- __memcg_kmem_uncharge(page, order);
+ __memcg_kmem_uncharge_page(page, order);
if (check_free)
bad += free_pages_check(page);
if (bad)
@@ -4777,7 +4777,7 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid,

out:
if (memcg_kmem_enabled() && (gfp_mask & __GFP_ACCOUNT) && page &&
- unlikely(__memcg_kmem_charge(page, gfp_mask, order) != 0)) {
+ unlikely(__memcg_kmem_charge_page(page, gfp_mask, order) != 0)) {
__free_pages(page, order);
page = NULL;
}
--
2.21.1