mm: memcontrol: rein in the CONFIG space madness
What CONFIG_INET and CONFIG_LEGACY_KMEM guard inside the memory
controller code is insignificant, having these conditionals is not
worth the complication and fragility that comes with them.
[akpm@linux-foundation.org: rework mem_cgroup_css_free() statement ordering]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 2bb14d02..47995b4 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -233,9 +233,11 @@
*/
struct mem_cgroup_stat_cpu __percpu *stat;
-#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)
+ unsigned long socket_pressure;
+
+ /* Legacy tcp memory accounting */
struct cg_proto tcp_mem;
-#endif
+
#ifndef CONFIG_SLOB
/* Index in the kmem_cache->memcg_params.memcg_caches array */
int kmemcg_id;
@@ -254,10 +256,6 @@
struct wb_domain cgwb_domain;
#endif
-#ifdef CONFIG_INET
- unsigned long socket_pressure;
-#endif
-
/* List of events which userspace want to receive */
struct list_head event_list;
spinlock_t event_list_lock;
@@ -712,15 +710,13 @@
void sock_release_memcg(struct sock *sk);
bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
-#if defined(CONFIG_MEMCG) && defined(CONFIG_INET)
+#ifdef CONFIG_MEMCG
extern struct static_key_false memcg_sockets_enabled_key;
#define mem_cgroup_sockets_enabled static_branch_unlikely(&memcg_sockets_enabled_key)
static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
{
-#ifdef CONFIG_MEMCG_LEGACY_KMEM
if (memcg->tcp_mem.memory_pressure)
return true;
-#endif
do {
if (time_before(jiffies, memcg->socket_pressure))
return true;
diff --git a/init/Kconfig b/init/Kconfig
index a0a15ce..2232080 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -964,20 +964,6 @@
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_LEGACY_KMEM
- bool
-config MEMCG_KMEM
- bool "Legacy Memory Resource Controller Kernel Memory accounting"
- depends on MEMCG
- depends on SLUB || SLAB
- select MEMCG_LEGACY_KMEM
- help
- The Kernel Memory extension for Memory Resource Controller can limit
- the amount of memory used by kernel objects in the system. Those are
- fundamentally different from the entities handled by the standard
- Memory Controller, which are page-based, and can be swapped. Users of
- the kmem extension can use it to guarantee that no group of processes
- will ever exhaust kernel resources alone.
config BLK_CGROUP
bool "IO controller"
@@ -1190,10 +1176,9 @@
to provide different user info for different servers.
When user namespaces are enabled in the kernel it is
- recommended that the MEMCG and MEMCG_KMEM options also be
- enabled and that user-space use the memory control groups to
- limit the amount of memory a memory unprivileged users can
- use.
+ recommended that the MEMCG option also be enabled and that
+ user-space use the memory control groups to limit the amount
+ of memory a memory unprivileged users can use.
If unsure, say N.
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 1589670..379f991 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2842,11 +2842,9 @@
case _KMEM:
counter = &memcg->kmem;
break;
-#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)
case _TCP:
counter = &memcg->tcp_mem.memory_allocated;
break;
-#endif
default:
BUG();
}
@@ -3006,7 +3004,6 @@
}
#endif /* !CONFIG_SLOB */
-#ifdef CONFIG_MEMCG_LEGACY_KMEM
static int memcg_update_kmem_limit(struct mem_cgroup *memcg,
unsigned long limit)
{
@@ -3024,16 +3021,7 @@
mutex_unlock(&memcg_limit_mutex);
return ret;
}
-#else
-static int memcg_update_kmem_limit(struct mem_cgroup *memcg,
- unsigned long limit)
-{
- return -EINVAL;
-}
-#endif /* CONFIG_MEMCG_LEGACY_KMEM */
-
-#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)
static int memcg_update_tcp_limit(struct mem_cgroup *memcg, unsigned long limit)
{
int ret;
@@ -3068,12 +3056,6 @@
mutex_unlock(&memcg_limit_mutex);
return ret;
}
-#else
-static int memcg_update_tcp_limit(struct mem_cgroup *memcg, unsigned long limit)
-{
- return -EINVAL;
-}
-#endif /* CONFIG_MEMCG_LEGACY_KMEM && CONFIG_INET */
/*
* The user of this function is...
@@ -3136,11 +3118,9 @@
case _KMEM:
counter = &memcg->kmem;
break;
-#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)
case _TCP:
counter = &memcg->tcp_mem.memory_allocated;
break;
-#endif
default:
BUG();
}
@@ -4094,7 +4074,6 @@
.seq_show = memcg_numa_stat_show,
},
#endif
-#ifdef CONFIG_MEMCG_LEGACY_KMEM
{
.name = "kmem.limit_in_bytes",
.private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT),
@@ -4127,7 +4106,6 @@
.seq_show = memcg_slab_show,
},
#endif
-#ifdef CONFIG_INET
{
.name = "kmem.tcp.limit_in_bytes",
.private = MEMFILE_PRIVATE(_TCP, RES_LIMIT),
@@ -4151,8 +4129,6 @@
.write = mem_cgroup_reset,
.read_u64 = mem_cgroup_read_u64,
},
-#endif
-#endif
{ }, /* terminate */
};
@@ -4280,15 +4256,13 @@
vmpressure_init(&memcg->vmpressure);
INIT_LIST_HEAD(&memcg->event_list);
spin_lock_init(&memcg->event_list_lock);
+ memcg->socket_pressure = jiffies;
#ifndef CONFIG_SLOB
memcg->kmemcg_id = -1;
#endif
#ifdef CONFIG_CGROUP_WRITEBACK
INIT_LIST_HEAD(&memcg->cgwb_list);
#endif
-#ifdef CONFIG_INET
- memcg->socket_pressure = jiffies;
-#endif
return &memcg->css;
free_out:
@@ -4321,10 +4295,8 @@
memcg->soft_limit = PAGE_COUNTER_MAX;
page_counter_init(&memcg->memsw, &parent->memsw);
page_counter_init(&memcg->kmem, &parent->kmem);
-#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)
page_counter_init(&memcg->tcp_mem.memory_allocated,
&parent->tcp_mem.memory_allocated);
-#endif
/*
* No need to take a reference to the parent because cgroup
@@ -4336,9 +4308,7 @@
memcg->soft_limit = PAGE_COUNTER_MAX;
page_counter_init(&memcg->memsw, NULL);
page_counter_init(&memcg->kmem, NULL);
-#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)
page_counter_init(&memcg->tcp_mem.memory_allocated, NULL);
-#endif
/*
* Deeper hierachy with use_hierarchy == false doesn't make
* much sense so let cgroup subsystem know about this
@@ -4353,10 +4323,8 @@
if (ret)
return ret;
-#ifdef CONFIG_INET
if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket)
static_branch_inc(&memcg_sockets_enabled_key);
-#endif
/*
* Make sure the memcg is initialized: mem_cgroup_iter()
@@ -4403,18 +4371,13 @@
{
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
-#ifdef CONFIG_INET
if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket)
static_branch_dec(&memcg_sockets_enabled_key);
-#endif
- memcg_free_kmem(memcg);
-
-#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)
if (memcg->tcp_mem.active)
static_branch_dec(&memcg_sockets_enabled_key);
-#endif
+ memcg_free_kmem(memcg);
__mem_cgroup_free(memcg);
}
@@ -5613,8 +5576,6 @@
commit_charge(newpage, memcg, true);
}
-#ifdef CONFIG_INET
-
DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key);
EXPORT_SYMBOL(memcg_sockets_enabled_key);
@@ -5640,10 +5601,8 @@
memcg = mem_cgroup_from_task(current);
if (memcg == root_mem_cgroup)
goto out;
-#ifdef CONFIG_MEMCG_LEGACY_KMEM
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && !memcg->tcp_mem.active)
goto out;
-#endif
if (css_tryget_online(&memcg->css))
sk->sk_memcg = memcg;
out:
@@ -5669,7 +5628,6 @@
{
gfp_t gfp_mask = GFP_KERNEL;
-#ifdef CONFIG_MEMCG_LEGACY_KMEM
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) {
struct page_counter *counter;
@@ -5682,7 +5640,7 @@
memcg->tcp_mem.memory_pressure = 1;
return false;
}
-#endif
+
/* Don't block in the packet receive path */
if (in_softirq())
gfp_mask = GFP_NOWAIT;
@@ -5701,19 +5659,16 @@
*/
void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages)
{
-#ifdef CONFIG_MEMCG_LEGACY_KMEM
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) {
page_counter_uncharge(&memcg->tcp_mem.memory_allocated,
nr_pages);
return;
}
-#endif
+
page_counter_uncharge(&memcg->memory, nr_pages);
css_put_many(&memcg->css, nr_pages);
}
-#endif /* CONFIG_INET */
-
static int __init cgroup_memory(char *s)
{
char *token;
diff --git a/mm/vmpressure.c b/mm/vmpressure.c
index 89b1d44..9a6c070 100644
--- a/mm/vmpressure.c
+++ b/mm/vmpressure.c
@@ -275,7 +275,6 @@
level = vmpressure_calc_level(scanned, reclaimed);
-#ifdef CONFIG_INET
if (level > VMPRESSURE_LOW) {
/*
* Let the socket buffer allocator know that
@@ -287,7 +286,6 @@
*/
memcg->socket_pressure = jiffies + HZ;
}
-#endif
}
}