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Diffstat (limited to 'net/ipv4/tcp.c')
-rw-r--r--net/ipv4/tcp.c38
1 files changed, 33 insertions, 5 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 414c179c28e0..c2d9830136d2 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -287,8 +287,8 @@ enum {
TCP_CMSG_TS = 2
};
-struct percpu_counter tcp_orphan_count;
-EXPORT_SYMBOL_GPL(tcp_orphan_count);
+DEFINE_PER_CPU(unsigned int, tcp_orphan_count);
+EXPORT_PER_CPU_SYMBOL_GPL(tcp_orphan_count);
long sysctl_tcp_mem[3] __read_mostly;
EXPORT_SYMBOL(sysctl_tcp_mem);
@@ -2673,11 +2673,36 @@ void tcp_shutdown(struct sock *sk, int how)
}
EXPORT_SYMBOL(tcp_shutdown);
+int tcp_orphan_count_sum(void)
+{
+ int i, total = 0;
+
+ for_each_possible_cpu(i)
+ total += per_cpu(tcp_orphan_count, i);
+
+ return max(total, 0);
+}
+
+static int tcp_orphan_cache;
+static struct timer_list tcp_orphan_timer;
+#define TCP_ORPHAN_TIMER_PERIOD msecs_to_jiffies(100)
+
+static void tcp_orphan_update(struct timer_list *unused)
+{
+ WRITE_ONCE(tcp_orphan_cache, tcp_orphan_count_sum());
+ mod_timer(&tcp_orphan_timer, jiffies + TCP_ORPHAN_TIMER_PERIOD);
+}
+
+static bool tcp_too_many_orphans(int shift)
+{
+ return READ_ONCE(tcp_orphan_cache) << shift > sysctl_tcp_max_orphans;
+}
+
bool tcp_check_oom(struct sock *sk, int shift)
{
bool too_many_orphans, out_of_socket_memory;
- too_many_orphans = tcp_too_many_orphans(sk, shift);
+ too_many_orphans = tcp_too_many_orphans(shift);
out_of_socket_memory = tcp_out_of_memory(sk);
if (too_many_orphans)
@@ -2786,7 +2811,7 @@ adjudge_to_death:
/* remove backlog if any, without releasing ownership. */
__release_sock(sk);
- percpu_counter_inc(sk->sk_prot->orphan_count);
+ this_cpu_inc(tcp_orphan_count);
/* Have we already been destroyed by a softirq or backlog? */
if (state != TCP_CLOSE && sk->sk_state == TCP_CLOSE)
@@ -4479,7 +4504,10 @@ void __init tcp_init(void)
sizeof_field(struct sk_buff, cb));
percpu_counter_init(&tcp_sockets_allocated, 0, GFP_KERNEL);
- percpu_counter_init(&tcp_orphan_count, 0, GFP_KERNEL);
+
+ timer_setup(&tcp_orphan_timer, tcp_orphan_update, TIMER_DEFERRABLE);
+ mod_timer(&tcp_orphan_timer, jiffies + TCP_ORPHAN_TIMER_PERIOD);
+
inet_hashinfo_init(&tcp_hashinfo);
inet_hashinfo2_init(&tcp_hashinfo, "tcp_listen_portaddr_hash",
thash_entries, 21, /* one slot per 2 MB*/