#include <linux/memcontrol.h>
#include <linux/module.h>
-static u64 tcp_cgroup_read(struct cgroup *cont, struct cftype *cft);
-static int tcp_cgroup_write(struct cgroup *cont, struct cftype *cft,
- const char *buffer);
-static int tcp_cgroup_reset(struct cgroup *cont, unsigned int event);
-
-static struct cftype tcp_files[] = {
- {
- .name = "kmem.tcp.limit_in_bytes",
- .write_string = tcp_cgroup_write,
- .read_u64 = tcp_cgroup_read,
- .private = RES_LIMIT,
- },
- {
- .name = "kmem.tcp.usage_in_bytes",
- .read_u64 = tcp_cgroup_read,
- .private = RES_USAGE,
- },
- {
- .name = "kmem.tcp.failcnt",
- .private = RES_FAILCNT,
- .trigger = tcp_cgroup_reset,
- .read_u64 = tcp_cgroup_read,
- },
- {
- .name = "kmem.tcp.max_usage_in_bytes",
- .private = RES_MAX_USAGE,
- .trigger = tcp_cgroup_reset,
- .read_u64 = tcp_cgroup_read,
- },
-};
-
static inline struct tcp_memcontrol *tcp_from_cgproto(struct cg_proto *cg_proto)
{
return container_of(cg_proto, struct tcp_memcontrol, cg_proto);
}
EXPORT_SYMBOL(memcg_tcp_enter_memory_pressure);
-int tcp_init_cgroup(struct cgroup *cgrp, struct cgroup_subsys *ss)
+int tcp_init_cgroup(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
{
/*
* The root cgroup does not use res_counters, but rather,
struct res_counter *res_parent = NULL;
struct cg_proto *cg_proto, *parent_cg;
struct tcp_memcontrol *tcp;
- struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
struct mem_cgroup *parent = parent_mem_cgroup(memcg);
struct net *net = current->nsproxy->net_ns;
cg_proto = tcp_prot.proto_cgroup(memcg);
if (!cg_proto)
- goto create_files;
+ return 0;
tcp = tcp_from_cgproto(cg_proto);
cg_proto->sockets_allocated = &tcp->tcp_sockets_allocated;
cg_proto->memcg = memcg;
-create_files:
- return cgroup_add_files(cgrp, ss, tcp_files,
- ARRAY_SIZE(tcp_files));
+ return 0;
}
EXPORT_SYMBOL(tcp_init_cgroup);
-void tcp_destroy_cgroup(struct cgroup *cgrp)
+void tcp_destroy_cgroup(struct mem_cgroup *memcg)
{
- struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
struct cg_proto *cg_proto;
struct tcp_memcontrol *tcp;
u64 val;
percpu_counter_destroy(&tcp->tcp_sockets_allocated);
val = res_counter_read_u64(&tcp->tcp_memory_allocated, RES_LIMIT);
-
- if (val != RESOURCE_MAX)
- static_key_slow_dec(&memcg_socket_limit_enabled);
}
EXPORT_SYMBOL(tcp_destroy_cgroup);
tcp->tcp_prot_mem[i] = min_t(long, val >> PAGE_SHIFT,
net->ipv4.sysctl_tcp_mem[i]);
- if (val == RESOURCE_MAX && old_lim != RESOURCE_MAX)
- static_key_slow_dec(&memcg_socket_limit_enabled);
- else if (old_lim == RESOURCE_MAX && val != RESOURCE_MAX)
- static_key_slow_inc(&memcg_socket_limit_enabled);
+ if (val == RESOURCE_MAX)
+ clear_bit(MEMCG_SOCK_ACTIVE, &cg_proto->flags);
+ else if (val != RESOURCE_MAX) {
+ /*
+ * 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 memcg until that flag is up.
+ *
+ * We need to do this, because static_keys will span multiple
+ * sites, but we can't control their order. If we mark a socket
+ * as accounted, but the accounting functions are not patched in
+ * yet, we'll lose accounting.
+ *
+ * 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 (!test_and_set_bit(MEMCG_SOCK_ACTIVATED, &cg_proto->flags))
+ static_key_slow_inc(&memcg_socket_limit_enabled);
+ set_bit(MEMCG_SOCK_ACTIVE, &cg_proto->flags);
+ }
return 0;
}
tcp->tcp_prot_mem[idx] = val;
}
+
+static struct cftype tcp_files[] = {
+ {
+ .name = "kmem.tcp.limit_in_bytes",
+ .write_string = tcp_cgroup_write,
+ .read_u64 = tcp_cgroup_read,
+ .private = RES_LIMIT,
+ },
+ {
+ .name = "kmem.tcp.usage_in_bytes",
+ .read_u64 = tcp_cgroup_read,
+ .private = RES_USAGE,
+ },
+ {
+ .name = "kmem.tcp.failcnt",
+ .private = RES_FAILCNT,
+ .trigger = tcp_cgroup_reset,
+ .read_u64 = tcp_cgroup_read,
+ },
+ {
+ .name = "kmem.tcp.max_usage_in_bytes",
+ .private = RES_MAX_USAGE,
+ .trigger = tcp_cgroup_reset,
+ .read_u64 = tcp_cgroup_read,
+ },
+ { } /* terminate */
+};
+
+static int __init tcp_memcontrol_init(void)
+{
+ WARN_ON(cgroup_add_cftypes(&mem_cgroup_subsys, tcp_files));
+ return 0;
+}
+__initcall(tcp_memcontrol_init);
projects / firefly-linux-kernel-4.4.55.git / blobdiff