Commit 2c8d8f97 authored by Suren Baghdasaryan's avatar Suren Baghdasaryan Committed by Linus Torvalds
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mm, memcg: inline mem_cgroup_{charge/uncharge} to improve disabled memcg config 

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 [1]
comparing {CONFIG_MEMCG=n} against {CONFIG_MEMCG=y, cgroup_disable=memory}
configuration on an 8-core ARM64 Android device.

[1] https://lkml.org/lkml/2006/8/29/294 also used in mmtests suite

Link: https://lkml.kernel.org/r/20210713010934.299876-2-surenb@google.com


Signed-off-by: default avatarSuren Baghdasaryan <surenb@google.com>
Reviewed-by: default avatarShakeel Butt <shakeelb@google.com>
Reviewed-by: default avatarMuchun Song <songmuchun@bytedance.com>
Acked-by: default avatarMichal Hocko <mhocko@suse.com>
Acked-by: default avatarJohannes Weiner <hannes@cmpxchg.org>
Cc: Alex Shi <alexs@kernel.org>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 56cab285

include/linux/memcontrol.h

+25 −3
Original line number Diff line number Diff line
@@ -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);

mm/memcontrol.c

+12 −21
Original line number Diff line number Diff line
@@ -6693,8 +6693,7 @@ 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;
@@ -6715,7 +6714,7 @@ 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
@@ -6728,16 +6727,14 @@ 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;
@@ -6772,7 +6769,7 @@ 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;
@@ -6908,18 +6905,15 @@ 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().

 * 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;
@@ -6930,20 +6924,17 @@ 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().

 * __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);