From: Chen Xiaoguang <xiaoggchen@xxxxxxxxxxx>
Check memory cgroup limit before allocating real memory. This may
improve performance especially in slow path when memory allocation
exceeds cgroup limitation.
Signed-off-by: Chen Xiaoguang <xiaoggchen@xxxxxxxxxxx>
Signed-off-by: Chen He <heddchen@xxxxxxxxxxx>
---
include/linux/memcontrol.h | 30 ++++++++++++++++++++++--------
mm/memcontrol.c | 34 ++++++++++++++++------------------
mm/page_alloc.c | 24 +++++++++++++++++-------
3 files changed, 55 insertions(+), 33 deletions(-)
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 0c04d39..59bb3ba 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -1583,8 +1583,9 @@ static inline void memcg_set_shrinker_bit(struct mem_cgroup *memcg,
#endif
#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_page(struct mem_cgroup *memcg, gfp_t gfp, int order);
+void __memcg_kmem_uncharge_page(struct page *page, int order,
+ struct mem_cgroup *memcg);
struct obj_cgroup *get_obj_cgroup_from_current(void);
@@ -1610,18 +1611,30 @@ static inline bool memcg_kmem_enabled(void)
return static_branch_likely(&memcg_kmem_enabled_key);
}
+extern struct mem_cgroup *get_mem_cgroup_from_current(void);
+
static inline int memcg_kmem_charge_page(struct page *page, gfp_t gfp,
int order)
{
- if (memcg_kmem_enabled())
- return __memcg_kmem_charge_page(page, gfp, order);
- return 0;
+ struct mem_cgroup *memcg;
+ int ret = 0;
+
+ memcg = get_mem_cgroup_from_current();
+ if (memcg && memcg_kmem_enabled() && !mem_cgroup_is_root(memcg)) {
+ ret = __memcg_kmem_charge_page(memcg, gfp, order);
+ if (!ret) {
+ page->memcg_data = (unsigned long)memcg | MEMCG_DATA_KMEM;
+ return 0;
+ }
+ css_put(&memcg->css);
+ }
+ return ret;
}
static inline void memcg_kmem_uncharge_page(struct page *page, int order)
{
if (memcg_kmem_enabled())
- __memcg_kmem_uncharge_page(page, order);
+ __memcg_kmem_uncharge_page(page, order, NULL);
}
/*
@@ -1647,13 +1660,14 @@ static inline void memcg_kmem_uncharge_page(struct page *page, int order)
{
}
-static inline int __memcg_kmem_charge_page(struct page *page, gfp_t gfp,
+static inline int __memcg_kmem_charge_page(struct mem_cgroup *memcg, gfp_t gfp,
int order)
{
return 0;
}
-static inline void __memcg_kmem_uncharge_page(struct page *page, int order)
+static inline void __memcg_kmem_uncharge_page(struct page *page, int order,
+ struct mem_cgroup *memcg)
{
}
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index e064ac0d..8df57b7 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1085,7 +1085,7 @@ static __always_inline bool memcg_kmem_bypass(void)
/**
* If active memcg is set, do not fallback to current->mm->memcg.
*/
-static __always_inline struct mem_cgroup *get_mem_cgroup_from_current(void)
+struct mem_cgroup *get_mem_cgroup_from_current(void)
{
if (memcg_kmem_bypass())
return NULL;
@@ -3113,21 +3113,11 @@ static void __memcg_kmem_uncharge(struct mem_cgroup *memcg, unsigned int nr_page
*
* Returns 0 on success, an error code on failure.
*/
-int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order)
+int __memcg_kmem_charge_page(struct mem_cgroup *memcg, gfp_t gfp, int order)
{
- struct mem_cgroup *memcg;
- int ret = 0;
+ int ret;
- memcg = get_mem_cgroup_from_current();
- if (memcg && !mem_cgroup_is_root(memcg)) {
- ret = __memcg_kmem_charge(memcg, gfp, 1 << order);
- if (!ret) {
- page->memcg_data = (unsigned long)memcg |
- MEMCG_DATA_KMEM;
- return 0;
- }
- css_put(&memcg->css);
- }
+ ret = __memcg_kmem_charge(memcg, gfp, 1 << order);
return ret;
}
@@ -3136,17 +3126,25 @@ int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order)
* @page: page to uncharge
* @order: allocation order
*/
-void __memcg_kmem_uncharge_page(struct page *page, int order)
+void __memcg_kmem_uncharge_page(struct page *page, int order,
+ struct mem_cgroup *memcg_in)
{
- struct mem_cgroup *memcg = page_memcg(page);
+ struct mem_cgroup *memcg;
unsigned int nr_pages = 1 << order;
+ if (page)
+ memcg = page_memcg(page);
+ else
+ memcg = memcg_in;
+
if (!memcg)
return;
- VM_BUG_ON_PAGE(mem_cgroup_is_root(memcg), page);
+ if (page)
+ VM_BUG_ON_PAGE(mem_cgroup_is_root(memcg), page);
__memcg_kmem_uncharge(memcg, nr_pages);
- page->memcg_data = 0;
+ if (page)
+ page->memcg_data = 0;
css_put(&memcg->css);
}
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index cfc7287..c3d1d0c 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1230,7 +1230,7 @@ static __always_inline bool free_pages_prepare(struct page *page,
* Untie memcg state and reset page's owner
*/
if (memcg_kmem_enabled() && PageMemcgKmem(page))
- __memcg_kmem_uncharge_page(page, order);
+ __memcg_kmem_uncharge_page(page, order, NULL);
reset_page_owner(page, order);
return false;
}
@@ -1260,7 +1260,7 @@ static __always_inline bool free_pages_prepare(struct page *page,
if (PageMappingFlags(page))
page->mapping = NULL;
if (memcg_kmem_enabled() && PageMemcgKmem(page))
- __memcg_kmem_uncharge_page(page, order);
+ __memcg_kmem_uncharge_page(page, order, NULL);
if (check_free)
bad += check_free_page(page);
if (bad)
@@ -4976,6 +4976,8 @@ struct page *
unsigned int alloc_flags = ALLOC_WMARK_LOW;
gfp_t alloc_mask; /* The gfp_t that was actually used for allocation */
struct alloc_context ac = { };
+ struct mem_cgroup *memcg;
+ bool charged = false;
/*
* There are several places where we assume that the order value is sane
@@ -4987,6 +4989,15 @@ struct page *
}
gfp_mask &= gfp_allowed_mask;
+ memcg = get_mem_cgroup_from_current();
+ if (memcg && memcg_kmem_enabled() && (gfp_mask & __GFP_ACCOUNT) &&
+ !mem_cgroup_is_root(memcg)) {
+ if (unlikely(__memcg_kmem_charge_page(memcg, gfp_mask, order) != 0)) {
+ css_put(&memcg->css);
+ return NULL;
+ }
+ charged = true;
+ }
alloc_mask = gfp_mask;
if (!prepare_alloc_pages(gfp_mask, order, preferred_nid, nodemask, &ac, &alloc_mask, &alloc_flags))
return NULL;
@@ -5020,11 +5031,10 @@ struct page *
page = __alloc_pages_slowpath(alloc_mask, order, &ac);
out:
- if (memcg_kmem_enabled() && (gfp_mask & __GFP_ACCOUNT) && page &&
- unlikely(__memcg_kmem_charge_page(page, gfp_mask, order) != 0)) {
- __free_pages(page, order);
- page = NULL;
- }
+ if (page && charged)
+ page->memcg_data = (unsigned long)memcg | MEMCG_DATA_KMEM;
+ else if (charged)
+ __memcg_kmem_uncharge_page(NULL, order, memcg);
trace_mm_page_alloc(page, order, alloc_mask, ac.migratetype);
--
1.8.3.1
