mm: memcontrol: introduce CONFIG_MEMCG_LEGACY_KMEM
Let the user know that CONFIG_MEMCG_KMEM does not apply to the cgroup2
interface. This also makes legacy-only code sections stand out better.
[arnd@arndb.de: mm: memcontrol: only manage socket pressure for CONFIG_INET]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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 a87704e..2bb14d02 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -233,7 +233,7 @@
*/
struct mem_cgroup_stat_cpu __percpu *stat;
-#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_INET)
+#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)
struct cg_proto tcp_mem;
#endif
#ifndef CONFIG_SLOB
@@ -717,7 +717,7 @@
#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_KMEM
+#ifdef CONFIG_MEMCG_LEGACY_KMEM
if (memcg->tcp_mem.memory_pressure)
return true;
#endif
diff --git a/init/Kconfig b/init/Kconfig
index 5b86082..a0a15ce 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -964,10 +964,13 @@
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 "Memory Resource Controller Kernel Memory accounting"
+ 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
@@ -1071,6 +1074,11 @@
Provides a way to freeze and unfreeze all tasks in a
cgroup.
+ This option affects the ORIGINAL cgroup interface. The cgroup2 memory
+ controller includes important in-kernel memory consumers per default.
+
+ If you're using cgroup2, say N.
+
config CGROUP_HUGETLB
bool "HugeTLB controller"
depends on HUGETLB_PAGE
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 2239e6dd..92e8ab6 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3001,7 +3001,7 @@
}
#endif /* !CONFIG_SLOB */
-#ifdef CONFIG_MEMCG_KMEM
+#ifdef CONFIG_MEMCG_LEGACY_KMEM
static int memcg_update_kmem_limit(struct mem_cgroup *memcg,
unsigned long limit)
{
@@ -3025,7 +3025,7 @@
{
return -EINVAL;
}
-#endif /* CONFIG_MEMCG_KMEM */
+#endif /* CONFIG_MEMCG_LEGACY_KMEM */
/*
@@ -4039,7 +4039,7 @@
.seq_show = memcg_numa_stat_show,
},
#endif
-#ifdef CONFIG_MEMCG_KMEM
+#ifdef CONFIG_MEMCG_LEGACY_KMEM
{
.name = "kmem.limit_in_bytes",
.private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT),
@@ -4266,13 +4266,13 @@
if (ret)
return ret;
-#ifdef CONFIG_MEMCG_KMEM
+#ifdef CONFIG_INET
+#ifdef CONFIG_MEMCG_LEGACY_KMEM
ret = tcp_init_cgroup(memcg);
if (ret)
return ret;
#endif
-#ifdef CONFIG_INET
if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket)
static_branch_inc(&memcg_sockets_enabled_key);
#endif
@@ -4329,7 +4329,7 @@
memcg_free_kmem(memcg);
-#ifdef CONFIG_MEMCG_KMEM
+#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)
tcp_destroy_cgroup(memcg);
#endif
@@ -5558,7 +5558,7 @@
memcg = mem_cgroup_from_task(current);
if (memcg == root_mem_cgroup)
goto out;
-#ifdef CONFIG_MEMCG_KMEM
+#ifdef CONFIG_MEMCG_LEGACY_KMEM
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && !memcg->tcp_mem.active)
goto out;
#endif
@@ -5587,7 +5587,7 @@
{
gfp_t gfp_mask = GFP_KERNEL;
-#ifdef CONFIG_MEMCG_KMEM
+#ifdef CONFIG_MEMCG_LEGACY_KMEM
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) {
struct page_counter *counter;
@@ -5619,7 +5619,7 @@
*/
void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages)
{
-#ifdef CONFIG_MEMCG_KMEM
+#ifdef CONFIG_MEMCG_LEGACY_KMEM
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) {
page_counter_uncharge(&memcg->tcp_mem.memory_allocated,
nr_pages);
diff --git a/mm/vmpressure.c b/mm/vmpressure.c
index 9a6c070..89b1d44 100644
--- a/mm/vmpressure.c
+++ b/mm/vmpressure.c
@@ -275,6 +275,7 @@
level = vmpressure_calc_level(scanned, reclaimed);
+#ifdef CONFIG_INET
if (level > VMPRESSURE_LOW) {
/*
* Let the socket buffer allocator know that
@@ -286,6 +287,7 @@
*/
memcg->socket_pressure = jiffies + HZ;
}
+#endif
}
}
diff --git a/net/ipv4/Makefile b/net/ipv4/Makefile
index c29809f..bee5055 100644
--- a/net/ipv4/Makefile
+++ b/net/ipv4/Makefile
@@ -56,7 +56,7 @@
obj-$(CONFIG_TCP_CONG_LP) += tcp_lp.o
obj-$(CONFIG_TCP_CONG_YEAH) += tcp_yeah.o
obj-$(CONFIG_TCP_CONG_ILLINOIS) += tcp_illinois.o
-obj-$(CONFIG_MEMCG_KMEM) += tcp_memcontrol.o
+obj-$(CONFIG_MEMCG_LEGACY_KMEM) += tcp_memcontrol.o
obj-$(CONFIG_NETLABEL) += cipso_ipv4.o
obj-$(CONFIG_XFRM) += xfrm4_policy.o xfrm4_state.o xfrm4_input.o \