[PATCH v3 2/3] mm, memcg: inline mem_cgroup_{charge/uncharge} to improve disabled memcg config
From: Suren Baghdasaryan <surenb@google.com>
Date: 2021-07-10 00:36:38
Also in:
linux-mm, lkml
Subsystem:
control group - memory resource controller (memcg), memory management, the rest · Maintainers:
Johannes Weiner, Michal Hocko, Roman Gushchin, Shakeel Butt, Andrew Morton, Linus Torvalds
Inline mem_cgroup_{charge/uncharge} and mem_cgroup_uncharge_list functions
functions to perform mem_cgroup_disabled static key check inline before
calling the main body of the function. This minimizes the memcg overhead
in the pagefault and exit_mmap paths when memcgs are disabled using
cgroup_disable=memory command-line option.
This change results in ~0.4% overhead reduction when running PFT test
comparing {CONFIG_MEMCG=n} against {CONFIG_MEMCG=y, cgroup_disable=memory}
configurationon on an 8-core ARM64 Android device.
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Shakeel Butt <redacted>
---
include/linux/memcontrol.h | 28 +++++++++++++++++++++++++---
mm/memcontrol.c | 29 ++++++++++-------------------
2 files changed, 35 insertions(+), 22 deletions(-)
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index bfe5c486f4ad..39fa88051a42 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h@@ -693,13 +693,35 @@ static inline bool mem_cgroup_below_min(struct mem_cgroup *memcg) page_counter_read(&memcg->memory); } -int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask); +int __mem_cgroup_charge(struct page *page, struct mm_struct *mm, + gfp_t gfp_mask); +static inline int mem_cgroup_charge(struct page *page, struct mm_struct *mm, + gfp_t gfp_mask) +{ + if (mem_cgroup_disabled()) + return 0; + return __mem_cgroup_charge(page, mm, gfp_mask); +} + int mem_cgroup_swapin_charge_page(struct page *page, struct mm_struct *mm, gfp_t gfp, swp_entry_t entry); void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry); -void mem_cgroup_uncharge(struct page *page); -void mem_cgroup_uncharge_list(struct list_head *page_list); +void __mem_cgroup_uncharge(struct page *page); +static inline void mem_cgroup_uncharge(struct page *page) +{ + if (mem_cgroup_disabled()) + return; + __mem_cgroup_uncharge(page); +} + +void __mem_cgroup_uncharge_list(struct list_head *page_list); +static inline void mem_cgroup_uncharge_list(struct list_head *page_list) +{ + if (mem_cgroup_disabled()) + return; + __mem_cgroup_uncharge_list(page_list); +} void mem_cgroup_migrate(struct page *oldpage, struct page *newpage);
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index a228cd51c4bd..cdaf7003b43d 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c@@ -6701,8 +6701,7 @@ void mem_cgroup_calculate_protection(struct mem_cgroup *root, atomic_long_read(&parent->memory.children_low_usage))); } -static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg, - gfp_t gfp) +static int charge_memcg(struct page *page, struct mem_cgroup *memcg, gfp_t gfp) { unsigned int nr_pages = thp_nr_pages(page); int ret;
@@ -6723,7 +6722,7 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg, } /** - * mem_cgroup_charge - charge a newly allocated page to a cgroup + * __mem_cgroup_charge - charge a newly allocated page to a cgroup * @page: page to charge * @mm: mm context of the victim * @gfp_mask: reclaim mode
@@ -6736,16 +6735,14 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg, * * Returns 0 on success. Otherwise, an error code is returned. */ -int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask) +int __mem_cgroup_charge(struct page *page, struct mm_struct *mm, + gfp_t gfp_mask) { struct mem_cgroup *memcg; int ret; - if (mem_cgroup_disabled()) - return 0; - memcg = get_mem_cgroup_from_mm(mm); - ret = __mem_cgroup_charge(page, memcg, gfp_mask); + ret = charge_memcg(page, memcg, gfp_mask); css_put(&memcg->css); return ret;
@@ -6780,7 +6777,7 @@ int mem_cgroup_swapin_charge_page(struct page *page, struct mm_struct *mm, memcg = get_mem_cgroup_from_mm(mm); rcu_read_unlock(); - ret = __mem_cgroup_charge(page, memcg, gfp); + ret = charge_memcg(page, memcg, gfp); css_put(&memcg->css); return ret;
@@ -6916,18 +6913,15 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug) } /** - * mem_cgroup_uncharge - uncharge a page + * __mem_cgroup_uncharge - uncharge a page * @page: page to uncharge * * Uncharge a page previously charged with mem_cgroup_charge(). */ -void mem_cgroup_uncharge(struct page *page) +void __mem_cgroup_uncharge(struct page *page) { struct uncharge_gather ug; - if (mem_cgroup_disabled()) - return; - /* Don't touch page->lru of any random page, pre-check: */ if (!page_memcg(page)) return;
@@ -6938,20 +6932,17 @@ void mem_cgroup_uncharge(struct page *page) } /** - * mem_cgroup_uncharge_list - uncharge a list of page + * __mem_cgroup_uncharge_list - uncharge a list of page * @page_list: list of pages to uncharge * * Uncharge a list of pages previously charged with * mem_cgroup_charge(). */ -void mem_cgroup_uncharge_list(struct list_head *page_list) +void __mem_cgroup_uncharge_list(struct list_head *page_list) { struct uncharge_gather ug; struct page *page; - if (mem_cgroup_disabled()) - return; - uncharge_gather_clear(&ug); list_for_each_entry(page, page_list, lru) uncharge_page(page, &ug);
--
2.32.0.93.g670b81a890-goog