diff --git a/init/Kconfig b/init/Kconfig
index 74a5ac65644f3f825936f91134e14095e3f43851..ff5a827303dd8930ea97087cc33efc1652500d06 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -819,24 +819,9 @@ config MEMCG
Provides control over the memory footprint of tasks in a cgroup.
config MEMCG_SWAP
- bool "Swap controller"
+ bool
depends on MEMCG && SWAP
- help
- Provides control over the swap space consumed by tasks in a cgroup.
-
-config MEMCG_SWAP_ENABLED
- bool "Swap controller enabled by default"
- depends on MEMCG_SWAP
default y
- help
- Memory Resource Controller Swap Extension comes with its price in
- a bigger memory consumption. General purpose distribution kernels
- which want to enable the feature but keep it disabled by default
- and let the user enable it by swapaccount=1 boot command line
- parameter should have this option unselected.
- For those who want to have the feature enabled by default should
- select this option (if, for some reason, they need to disable it
- then swapaccount=0 does the trick).
config MEMCG_KMEM
bool
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 2d035e68a127e62b201ad9f175383de5fae6c495..425a265dc2a009ab58e27cae8a1fadf27f62c27c 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -83,14 +83,10 @@ static bool cgroup_memory_nokmem;
/* Whether the swap controller is active */
#ifdef CONFIG_MEMCG_SWAP
-#ifdef CONFIG_MEMCG_SWAP_ENABLED
bool cgroup_memory_noswap __read_mostly;
#else
-bool cgroup_memory_noswap __read_mostly = 1;
-#endif /* CONFIG_MEMCG_SWAP_ENABLED */
-#else
#define cgroup_memory_noswap 1
-#endif /* CONFIG_MEMCG_SWAP */
+#endif
#ifdef CONFIG_CGROUP_WRITEBACK
static DECLARE_WAIT_QUEUE_HEAD(memcg_cgwb_frn_waitq);
@@ -5360,8 +5356,7 @@ static struct page *mc_handle_swap_pte(struct vm_area_struct *vma,
* we call find_get_page() with swapper_space directly.
*/
page = find_get_page(swap_address_space(ent), swp_offset(ent));
- if (do_memsw_account())
- entry->val = ent.val;
+ entry->val = ent.val;
return page;
}
@@ -5395,8 +5390,7 @@ static struct page *mc_handle_file_pte(struct vm_area_struct *vma,
page = find_get_entry(mapping, pgoff);
if (xa_is_value(page)) {
swp_entry_t swp = radix_to_swp_entry(page);
- if (do_memsw_account())
- *entry = swp;
+ *entry = swp;
page = find_get_page(swap_address_space(swp),
swp_offset(swp));
}
@@ -6529,6 +6523,9 @@ int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask,
goto out;
if (PageSwapCache(page)) {
+ swp_entry_t ent = { .val = page_private(page), };
+ unsigned short id;
+
/*
* Every swap fault against a single page tries to charge the
* page, bail as early as possible. shmem_unuse() encounters
@@ -6540,17 +6537,12 @@ int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask,
if (compound_head(page)->mem_cgroup)
goto out;
- if (!cgroup_memory_noswap) {
- swp_entry_t ent = { .val = page_private(page), };
- unsigned short id;
-
- id = lookup_swap_cgroup_id(ent);
- rcu_read_lock();
- memcg = mem_cgroup_from_id(id);
- if (memcg && !css_tryget_online(&memcg->css))
- memcg = NULL;
- rcu_read_unlock();
- }
+ id = lookup_swap_cgroup_id(ent);
+ rcu_read_lock();
+ memcg = mem_cgroup_from_id(id);
+ if (memcg && !css_tryget_online(&memcg->css))
+ memcg = NULL;
+ rcu_read_unlock();
}
if (!memcg)
@@ -6567,7 +6559,7 @@ int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask,
memcg_check_events(memcg, page);
local_irq_enable();
- if (do_memsw_account() && PageSwapCache(page)) {
+ if (PageSwapCache(page)) {
swp_entry_t entry = { .val = page_private(page) };
/*
* The swap entry might not get freed for a long time,
@@ -6952,7 +6944,7 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
VM_BUG_ON_PAGE(PageLRU(page), page);
VM_BUG_ON_PAGE(page_count(page), page);
- if (!do_memsw_account())
+ if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
return;
memcg = page->mem_cgroup;
@@ -6981,7 +6973,7 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
if (!mem_cgroup_is_root(memcg))
page_counter_uncharge(&memcg->memory, nr_entries);
- if (memcg != swap_memcg) {
+ if (!cgroup_memory_noswap && memcg != swap_memcg) {
if (!mem_cgroup_is_root(swap_memcg))
page_counter_charge(&swap_memcg->memsw, nr_entries);
page_counter_uncharge(&memcg->memsw, nr_entries);
@@ -7017,7 +7009,7 @@ int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry)
struct mem_cgroup *memcg;
unsigned short oldid;
- if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) || cgroup_memory_noswap)
+ if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
return 0;
memcg = page->mem_cgroup;
@@ -7033,7 +7025,7 @@ int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry)
memcg = mem_cgroup_id_get_online(memcg);
- if (!mem_cgroup_is_root(memcg) &&
+ if (!cgroup_memory_noswap && !mem_cgroup_is_root(memcg) &&
!page_counter_try_charge(&memcg->swap, nr_pages, &counter)) {
memcg_memory_event(memcg, MEMCG_SWAP_MAX);
memcg_memory_event(memcg, MEMCG_SWAP_FAIL);
@@ -7061,14 +7053,11 @@ void mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages)
struct mem_cgroup *memcg;
unsigned short id;
- if (cgroup_memory_noswap)
- return;
-
id = swap_cgroup_record(entry, 0, nr_pages);
rcu_read_lock();
memcg = mem_cgroup_from_id(id);
if (memcg) {
- if (!mem_cgroup_is_root(memcg)) {
+ if (!cgroup_memory_noswap && !mem_cgroup_is_root(memcg)) {
if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
page_counter_uncharge(&memcg->swap, nr_pages);
else
@@ -7253,7 +7242,11 @@ static struct cftype memsw_files[] = {
static int __init mem_cgroup_swap_init(void)
{
- if (mem_cgroup_disabled() || cgroup_memory_noswap)
+ /* No memory control -> no swap control */
+ if (mem_cgroup_disabled())
+ cgroup_memory_noswap = true;
+
+ if (cgroup_memory_noswap)
return 0;
WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, swap_files));
diff --git a/mm/swap_cgroup.c b/mm/swap_cgroup.c
index 7aa764f09079a2134b98838c5e15ea939a8a6fb7..7f34343c075a1cfbcad053aaa1d25bab7d548bf0 100644
--- a/mm/swap_cgroup.c
+++ b/mm/swap_cgroup.c
@@ -171,9 +171,6 @@ int swap_cgroup_swapon(int type, unsigned long max_pages)
unsigned long length;
struct swap_cgroup_ctrl *ctrl;
- if (cgroup_memory_noswap)
- return 0;
-
length = DIV_ROUND_UP(max_pages, SC_PER_PAGE);
array_size = length * sizeof(void *);
@@ -209,9 +206,6 @@ void swap_cgroup_swapoff(int type)
unsigned long i, length;
struct swap_cgroup_ctrl *ctrl;
- if (cgroup_memory_noswap)
- return;
-
mutex_lock(&swap_cgroup_mutex);
ctrl = &swap_cgroup_ctrl[type];
map = ctrl->map;