After merge the CONFIG_MEMCG_SWAP into kernel as default feature. This
patch removes the kernel parameter interface swapaccount= to keep this
feature from user disable in boot.
Now, all swapped memcg page record it's id permanently.
Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Vladimir Davydov <vdavydov.dev@xxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: linux-doc@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: cgroups@xxxxxxxxxxxxxxx
Cc: linux-mm@xxxxxxxxx
---
Documentation/admin-guide/kernel-parameters.txt | 5 ---
include/linux/memcontrol.h | 2 -
mm/memcontrol.c | 50 ++++++++-----------------
mm/swap_cgroup.c | 7 ----
4 files changed, 15 insertions(+), 49 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index f2a93c8679e8..f8532dfc4f17 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -4877,11 +4877,6 @@
This parameter controls use of the Protected
Execution Facility on pSeries.
- swapaccount=[0|1]
- [KNL] Enable accounting of swap in memory resource
- controller if no parameter or 1 is given or disable
- it if 0 is given (See Documentation/admin-guide/cgroup-v1/memory.rst)
-
swiotlb= [ARM,IA-64,PPC,MIPS,X86]
Format: { <int> | force | noforce }
<int> -- Number of I/O TLB slabs
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 45842ed8ba53..9d6330ef5a13 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -569,8 +569,6 @@ struct mem_cgroup *mem_cgroup_get_oom_group(struct task_struct *victim,
struct mem_cgroup *oom_domain);
void mem_cgroup_print_oom_group(struct mem_cgroup *memcg);
-extern int do_swap_account;
-
struct mem_cgroup *lock_page_memcg(struct page *page);
void __unlock_page_memcg(struct mem_cgroup *memcg);
void unlock_page_memcg(struct page *page);
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 446141b6597a..ba3ac7c7644b 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -81,9 +81,6 @@
/* Kernel memory accounting disabled? */
static bool cgroup_memory_nokmem;
-/* Whether the swap controller is active */
-int do_swap_account __read_mostly;
-
#ifdef CONFIG_CGROUP_WRITEBACK
static DECLARE_WAIT_QUEUE_HEAD(memcg_cgwb_frn_waitq);
#endif
@@ -91,7 +88,7 @@
/* Whether legacy memory+swap accounting is active */
static bool do_memsw_account(void)
{
- return !cgroup_subsys_on_dfl(memory_cgrp_subsys) && do_swap_account;
+ return !cgroup_subsys_on_dfl(memory_cgrp_subsys);
}
#define THRESHOLDS_EVENTS_TARGET 128
@@ -6444,6 +6441,9 @@ int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
goto out;
if (PageSwapCache(page)) {
+ swp_entry_t ent;
+ unsigned short id;
+
/*
* Every swap fault against a single page tries to charge the
* page, bail as early as possible. shmem_unuse() encounters
@@ -6455,16 +6455,13 @@ int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
if (compound_head(page)->mem_cgroup)
goto out;
- if (do_swap_account) {
- swp_entry_t ent = { .val = page_private(page), };
- unsigned short 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();
- }
+ ent.val = page_private(page);
+ 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)
@@ -7024,7 +7021,7 @@ 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) || !do_swap_account)
+ if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
return 0;
memcg = page->mem_cgroup;
@@ -7068,9 +7065,6 @@ void mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages)
struct mem_cgroup *memcg;
unsigned short id;
- if (!do_swap_account)
- return;
-
id = swap_cgroup_record(entry, 0, nr_pages);
rcu_read_lock();
memcg = mem_cgroup_from_id(id);
@@ -7091,7 +7085,7 @@ long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg)
{
long nr_swap_pages = get_nr_swap_pages();
- if (!do_swap_account || !cgroup_subsys_on_dfl(memory_cgrp_subsys))
+ if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
return nr_swap_pages;
for (; memcg != root_mem_cgroup; memcg = parent_mem_cgroup(memcg))
nr_swap_pages = min_t(long, nr_swap_pages,
@@ -7108,7 +7102,7 @@ bool mem_cgroup_swap_full(struct page *page)
if (vm_swap_full())
return true;
- if (!do_swap_account || !cgroup_subsys_on_dfl(memory_cgrp_subsys))
+ if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
return false;
memcg = page->mem_cgroup;
@@ -7123,19 +7117,6 @@ bool mem_cgroup_swap_full(struct page *page)
return false;
}
-/* for remember boot option*/
-static int really_do_swap_account __initdata = 1;
-
-static int __init enable_swap_account(char *s)
-{
- if (!strcmp(s, "1"))
- really_do_swap_account = 1;
- else if (!strcmp(s, "0"))
- really_do_swap_account = 0;
- return 1;
-}
-__setup("swapaccount=", enable_swap_account);
-
static u64 swap_current_read(struct cgroup_subsys_state *css,
struct cftype *cft)
{
@@ -7229,8 +7210,7 @@ static int swap_events_show(struct seq_file *m, void *v)
static int __init mem_cgroup_swap_init(void)
{
- if (!mem_cgroup_disabled() && really_do_swap_account) {
- do_swap_account = 1;
+ if (!mem_cgroup_disabled()) {
WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys,
swap_files));
WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys,
diff --git a/mm/swap_cgroup.c b/mm/swap_cgroup.c
index 45affaef3bc6..3cb015179d29 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 (!do_swap_account)
- return 0;
-
length = DIV_ROUND_UP(max_pages, SC_PER_PAGE);
array_size = length * sizeof(void *);
@@ -199,7 +196,6 @@ int swap_cgroup_swapon(int type, unsigned long max_pages)
return 0;
nomem:
pr_info("couldn't allocate enough memory for swap_cgroup\n");
- pr_info("swap_cgroup can be disabled by swapaccount=0 boot option\n");
return -ENOMEM;
}
@@ -209,9 +205,6 @@ void swap_cgroup_swapoff(int type)
unsigned long i, length;
struct swap_cgroup_ctrl *ctrl;
- if (!do_swap_account)
- return;
-
mutex_lock(&swap_cgroup_mutex);
ctrl = &swap_cgroup_ctrl[type];
map = ctrl->map;
--
1.8.3.1
