From: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Subject: mm, memcg: inline swap-related functions to improve disabled memcg config
Inline mem_cgroup_try_charge_swap, mem_cgroup_uncharge_swap and
cgroup_throttle_swaprate 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 ~1% 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/20210713010934.299876-3-surenb@xxxxxxxxxx
Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Reviewed-by: Shakeel Butt <shakeelb@xxxxxxxxxx>
Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Roman Gushchin <guro@xxxxxx>
Cc: Yang Shi <shy828301@xxxxxxxxx>
Cc: Alex Shi <alexs@xxxxxxxxxx>
Cc: Wei Yang <richard.weiyang@xxxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Alistair Popple <apopple@xxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/swap.h | 26 +++++++++++++++++++++++---
mm/memcontrol.c | 14 ++++----------
mm/swapfile.c | 5 +----
3 files changed, 28 insertions(+), 17 deletions(-)
--- a/include/linux/swap.h~mm-memcg-inline-swap-related-functions-to-improve-disabled-memcg-config
+++ a/include/linux/swap.h
@@ -721,7 +721,13 @@ static inline int mem_cgroup_swappiness(
#endif
#if defined(CONFIG_SWAP) && defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
-extern void cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask);
+extern void __cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask);
+static inline void cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask)
+{
+ if (mem_cgroup_disabled())
+ return;
+ __cgroup_throttle_swaprate(page, gfp_mask);
+}
#else
static inline void cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask)
{
@@ -730,8 +736,22 @@ static inline void cgroup_throttle_swapr
#ifdef CONFIG_MEMCG_SWAP
extern void mem_cgroup_swapout(struct page *page, swp_entry_t entry);
-extern int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry);
-extern void mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages);
+extern int __mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry);
+static inline int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry)
+{
+ if (mem_cgroup_disabled())
+ return 0;
+ return __mem_cgroup_try_charge_swap(page, entry);
+}
+
+extern void __mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages);
+static inline void mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages)
+{
+ if (mem_cgroup_disabled())
+ return;
+ __mem_cgroup_uncharge_swap(entry, nr_pages);
+}
+
extern long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg);
extern bool mem_cgroup_swap_full(struct page *page);
#else
--- a/mm/memcontrol.c~mm-memcg-inline-swap-related-functions-to-improve-disabled-memcg-config
+++ a/mm/memcontrol.c
@@ -7226,7 +7226,7 @@ void mem_cgroup_swapout(struct page *pag
}
/**
- * mem_cgroup_try_charge_swap - try charging swap space for a page
+ * __mem_cgroup_try_charge_swap - try charging swap space for a page
* @page: page being added to swap
* @entry: swap entry to charge
*
@@ -7234,16 +7234,13 @@ void mem_cgroup_swapout(struct page *pag
*
* Returns 0 on success, -ENOMEM on failure.
*/
-int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry)
+int __mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry)
{
unsigned int nr_pages = thp_nr_pages(page);
struct page_counter *counter;
struct mem_cgroup *memcg;
unsigned short oldid;
- if (mem_cgroup_disabled())
- return 0;
-
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
return 0;
@@ -7279,18 +7276,15 @@ int mem_cgroup_try_charge_swap(struct pa
}
/**
- * mem_cgroup_uncharge_swap - uncharge swap space
+ * __mem_cgroup_uncharge_swap - uncharge swap space
* @entry: swap entry to uncharge
* @nr_pages: the amount of swap space to uncharge
*/
-void mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages)
+void __mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages)
{
struct mem_cgroup *memcg;
unsigned short id;
- if (mem_cgroup_disabled())
- return;
-
id = swap_cgroup_record(entry, 0, nr_pages);
rcu_read_lock();
memcg = mem_cgroup_from_id(id);
--- a/mm/swapfile.c~mm-memcg-inline-swap-related-functions-to-improve-disabled-memcg-config
+++ a/mm/swapfile.c
@@ -3779,14 +3779,11 @@ static void free_swap_count_continuation
}
#if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
-void cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask)
+void __cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask)
{
struct swap_info_struct *si, *next;
int nid = page_to_nid(page);
- if (mem_cgroup_disabled())
- return;
-
if (!(gfp_mask & __GFP_IO))
return;
_
