2 #include <net/tcp_memcontrol.h>
5 #include <linux/nsproxy.h>
6 #include <linux/memcontrol.h>
7 #include <linux/module.h>
9 int tcp_init_cgroup(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
12 * The root cgroup does not use page_counters, but rather,
13 * rely on the data already collected by the network
16 struct mem_cgroup *parent = parent_mem_cgroup(memcg);
17 struct page_counter *counter_parent = NULL;
18 struct cg_proto *cg_proto, *parent_cg;
20 cg_proto = tcp_prot.proto_cgroup(memcg);
24 cg_proto->sysctl_mem[0] = sysctl_tcp_mem[0];
25 cg_proto->sysctl_mem[1] = sysctl_tcp_mem[1];
26 cg_proto->sysctl_mem[2] = sysctl_tcp_mem[2];
27 cg_proto->memory_pressure = 0;
28 cg_proto->memcg = memcg;
30 parent_cg = tcp_prot.proto_cgroup(parent);
32 counter_parent = &parent_cg->memory_allocated;
34 page_counter_init(&cg_proto->memory_allocated, counter_parent);
38 EXPORT_SYMBOL(tcp_init_cgroup);
40 void tcp_destroy_cgroup(struct mem_cgroup *memcg)
42 struct cg_proto *cg_proto;
44 cg_proto = tcp_prot.proto_cgroup(memcg);
49 static_key_slow_dec(&memcg_socket_limit_enabled);
52 EXPORT_SYMBOL(tcp_destroy_cgroup);
54 static int tcp_update_limit(struct mem_cgroup *memcg, unsigned long nr_pages)
56 struct cg_proto *cg_proto;
60 cg_proto = tcp_prot.proto_cgroup(memcg);
64 ret = page_counter_limit(&cg_proto->memory_allocated, nr_pages);
68 for (i = 0; i < 3; i++)
69 cg_proto->sysctl_mem[i] = min_t(long, nr_pages,
72 if (!cg_proto->active) {
74 * The active flag needs to be written after the static_key
75 * update. This is what guarantees that the socket activation
76 * function is the last one to run. See sock_update_memcg() for
77 * details, and note that we don't mark any socket as belonging
78 * to this memcg until that flag is up.
80 * We need to do this, because static_keys will span multiple
81 * sites, but we can't control their order. If we mark a socket
82 * as accounted, but the accounting functions are not patched in
83 * yet, we'll lose accounting.
85 * We never race with the readers in sock_update_memcg(),
86 * because when this value change, the code to process it is not
89 static_key_slow_inc(&memcg_socket_limit_enabled);
90 cg_proto->active = true;
103 static DEFINE_MUTEX(tcp_limit_mutex);
105 static ssize_t tcp_cgroup_write(struct kernfs_open_file *of,
106 char *buf, size_t nbytes, loff_t off)
108 struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
109 unsigned long nr_pages;
114 switch (of_cft(of)->private) {
116 /* see memcontrol.c */
117 ret = page_counter_memparse(buf, "-1", &nr_pages);
120 mutex_lock(&tcp_limit_mutex);
121 ret = tcp_update_limit(memcg, nr_pages);
122 mutex_unlock(&tcp_limit_mutex);
128 return ret ?: nbytes;
131 static u64 tcp_cgroup_read(struct cgroup_subsys_state *css, struct cftype *cft)
133 struct mem_cgroup *memcg = mem_cgroup_from_css(css);
134 struct cg_proto *cg_proto = tcp_prot.proto_cgroup(memcg);
137 switch (cft->private) {
140 return PAGE_COUNTER_MAX;
141 val = cg_proto->memory_allocated.limit;
146 val = atomic_long_read(&tcp_memory_allocated);
148 val = page_counter_read(&cg_proto->memory_allocated);
154 val = cg_proto->memory_allocated.failcnt;
159 val = cg_proto->memory_allocated.watermark;
168 static ssize_t tcp_cgroup_reset(struct kernfs_open_file *of,
169 char *buf, size_t nbytes, loff_t off)
171 struct mem_cgroup *memcg;
172 struct cg_proto *cg_proto;
174 memcg = mem_cgroup_from_css(of_css(of));
175 cg_proto = tcp_prot.proto_cgroup(memcg);
179 switch (of_cft(of)->private) {
181 page_counter_reset_watermark(&cg_proto->memory_allocated);
184 cg_proto->memory_allocated.failcnt = 0;
191 static struct cftype tcp_files[] = {
193 .name = "kmem.tcp.limit_in_bytes",
194 .write = tcp_cgroup_write,
195 .read_u64 = tcp_cgroup_read,
196 .private = RES_LIMIT,
199 .name = "kmem.tcp.usage_in_bytes",
200 .read_u64 = tcp_cgroup_read,
201 .private = RES_USAGE,
204 .name = "kmem.tcp.failcnt",
205 .private = RES_FAILCNT,
206 .write = tcp_cgroup_reset,
207 .read_u64 = tcp_cgroup_read,
210 .name = "kmem.tcp.max_usage_in_bytes",
211 .private = RES_MAX_USAGE,
212 .write = tcp_cgroup_reset,
213 .read_u64 = tcp_cgroup_read,
218 static int __init tcp_memcontrol_init(void)
220 WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys, tcp_files));
223 __initcall(tcp_memcontrol_init);