The patch titled
Subject: decrement static keys on real destroy time
has been added to the -mm tree. Its filename is
memcg-decrement-static-keys-at-real-destroy-time-v6.patch
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------------------------------------------------------
From: Glauber Costa <glommer@xxxxxxxxxxxxx>
Subject: decrement static keys on real destroy time
[v6: changed active and activated to a flags field, as suggested by akpm ]
Signed-off-by: Glauber Costa <glommer@xxxxxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Li Zefan <lizefan@xxxxxxxxxx>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/memcontrol.h | 5 +++++
include/net/sock.h | 20 +++++++++++---------
mm/memcontrol.c | 27 +++++++++++++++------------
net/ipv4/tcp_memcontrol.c | 14 ++++++++------
4 files changed, 39 insertions(+), 27 deletions(-)
diff -puN include/linux/memcontrol.h~memcg-decrement-static-keys-at-real-destroy-time-v6 include/linux/memcontrol.h
--- a/include/linux/memcontrol.h~memcg-decrement-static-keys-at-real-destroy-time-v6
+++ a/include/linux/memcontrol.h
@@ -405,6 +405,11 @@ enum {
OVER_LIMIT,
};
+enum sock_flag_bits {
+ MEMCG_SOCK_ACTIVE,
+ MEMCG_SOCK_ACTIVATED,
+};
+
struct sock;
#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
void sock_update_memcg(struct sock *sk);
diff -puN include/net/sock.h~memcg-decrement-static-keys-at-real-destroy-time-v6 include/net/sock.h
--- a/include/net/sock.h~memcg-decrement-static-keys-at-real-destroy-time-v6
+++ a/include/net/sock.h
@@ -927,15 +927,7 @@ struct cg_proto {
struct percpu_counter *sockets_allocated; /* Current number of sockets. */
int *memory_pressure;
long *sysctl_mem;
- /*
- * active means it is currently active, and new sockets should
- * be assigned to cgroups.
- *
- * activated means it was ever activated, and we need to
- * disarm the static keys on destruction
- */
- bool activated;
- bool active;
+ unsigned long flags;
/*
* memcg field is used to find which memcg we belong directly
* Each memcg struct can hold more than one cg_proto, so container_of
@@ -951,6 +943,16 @@ struct cg_proto {
extern int proto_register(struct proto *prot, int alloc_slab);
extern void proto_unregister(struct proto *prot);
+static inline bool memcg_proto_active(struct cg_proto *cg_proto)
+{
+ return cg_proto->flags & (1 << MEMCG_SOCK_ACTIVE);
+}
+
+static inline bool memcg_proto_activated(struct cg_proto *cg_proto)
+{
+ return cg_proto->flags & (1 << MEMCG_SOCK_ACTIVATED);
+}
+
#ifdef SOCK_REFCNT_DEBUG
static inline void sk_refcnt_debug_inc(struct sock *sk)
{
diff -puN mm/memcontrol.c~memcg-decrement-static-keys-at-real-destroy-time-v6 mm/memcontrol.c
--- a/mm/memcontrol.c~memcg-decrement-static-keys-at-real-destroy-time-v6
+++ a/mm/memcontrol.c
@@ -457,7 +457,7 @@ void sock_update_memcg(struct sock *sk)
rcu_read_lock();
memcg = mem_cgroup_from_task(current);
cg_proto = sk->sk_prot->proto_cgroup(memcg);
- if (!mem_cgroup_is_root(memcg) && cg_proto->active) {
+ if (!mem_cgroup_is_root(memcg) && memcg_proto_active(cg_proto)) {
mem_cgroup_get(memcg);
sk->sk_cgrp = cg_proto;
}
@@ -476,14 +476,6 @@ void sock_release_memcg(struct sock *sk)
}
}
-static void disarm_static_keys(struct mem_cgroup *memcg)
-{
-#ifdef CONFIG_INET
- if (memcg->tcp_mem.cg_proto.activated)
- static_key_slow_dec(&memcg_socket_limit_enabled);
-#endif
-}
-
#ifdef CONFIG_INET
struct cg_proto *tcp_proto_cgroup(struct mem_cgroup *memcg)
{
@@ -493,14 +485,25 @@ struct cg_proto *tcp_proto_cgroup(struct
return &memcg->tcp_mem.cg_proto;
}
EXPORT_SYMBOL(tcp_proto_cgroup);
-#endif /* CONFIG_INET */
+
+static void disarm_sock_keys(struct mem_cgroup *memcg)
+{
+ if (!memcg_proto_activated(&memcg->tcp_mem.cg_proto))
+ return;
+ static_key_slow_dec(&memcg_socket_limit_enabled);
+}
#else
-static inline void disarm_static_keys(struct mem_cgroup *memcg)
+static void disarm_sock_keys(struct mem_cgroup *memcg)
{
}
-
+#endif /* CONFIG_INET */
#endif /* CONFIG_CGROUP_MEM_RES_CTLR_KMEM */
+static void disarm_static_keys(struct mem_cgroup *memcg)
+{
+ disarm_sock_keys(memcg);
+}
+
static void drain_all_stock_async(struct mem_cgroup *memcg);
static struct mem_cgroup_per_zone *
diff -puN net/ipv4/tcp_memcontrol.c~memcg-decrement-static-keys-at-real-destroy-time-v6 net/ipv4/tcp_memcontrol.c
--- a/net/ipv4/tcp_memcontrol.c~memcg-decrement-static-keys-at-real-destroy-time-v6
+++ a/net/ipv4/tcp_memcontrol.c
@@ -105,10 +105,10 @@ static int tcp_update_limit(struct mem_c
net->ipv4.sysctl_tcp_mem[i]);
if (val == RESOURCE_MAX)
- cg_proto->active = false;
+ clear_bit(MEMCG_SOCK_ACTIVE, &cg_proto->flags);
else if (val != RESOURCE_MAX) {
/*
- * ->activated needs to be written after the static_key update.
+ * The active bit needs to be written after the static_key update.
* This is what guarantees that the socket activation function
* is the last one to run. See sock_update_memcg() for details,
* and note that we don't mark any socket as belonging to this
@@ -122,12 +122,14 @@ static int tcp_update_limit(struct mem_c
* We never race with the readers in sock_update_memcg(), because
* when this value change, the code to process it is not patched in
* yet.
+ *
+ * The activated bit is used to guarantee that no two writers will
+ * do the update in the same memcg. Without that, we can't properly
+ * shutdown the static key.
*/
- if (!cg_proto->activated) {
+ if (!test_and_set_bit(MEMCG_SOCK_ACTIVATED, &cg_proto->flags))
static_key_slow_inc(&memcg_socket_limit_enabled);
- cg_proto->activated = true;
- }
- cg_proto->active = true;
+ set_bit(MEMCG_SOCK_ACTIVE, &cg_proto->flags);
}
return 0;
_
Subject: Subject: decrement static keys on real destroy time
Patches currently in -mm which might be from glommer@xxxxxxxxxxxxx are
linux-next.patch
memcg-fix-change-behavior-of-shared-anon-at-moving-task.patch
mm-memcg-scanning_global_lru-means-mem_cgroup_disabled.patch
mm-memcg-move-reclaim_stat-into-lruvec.patch
mm-push-lru-index-into-shrink_active_list.patch
mm-push-lru-index-into-shrink_active_list-fix.patch
mm-mark-mm-inline-functions-as-__always_inline.patch
mm-remove-lru-type-checks-from-__isolate_lru_page.patch
mm-memcg-kill-mem_cgroup_lru_del.patch
mm-memcg-use-vm_swappiness-from-target-memory-cgroup.patch
memcg-fix-error-code-in-hugetlb_force_memcg_empty.patch
rescounters-add-res_counter_uncharge_until.patch
memcg-use-res_counter_uncharge_until-in-move_parent.patch
memcg-move-charges-to-root-cgroup-if-use_hierarchy=0.patch
memcg-dont-uncharge-in-mem_cgroup_move_account.patch
remove-__must_check-for-res_counter_charge_nofail.patch
memcg-always-free-struct-memcg-through-schedule_work.patch
memcg-always-free-struct-memcg-through-schedule_work-fix.patch
memcg-decrement-static-keys-at-real-destroy-time.patch
memcg-decrement-static-keys-at-real-destroy-time-v6.patch
memcg-decrement-static-keys-at-real-destroy-time-v6-fix.patch
syscalls-x86-add-__nr_kcmp-syscall-v8.patch
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