net: Disambiguate kernel message

Some of our machines were reporting:

TCP: too many of orphaned sockets

even when the number of orphaned sockets was well below the
limit.

We print a different message depending on whether we're out
of TCP memory or there are too many orphaned sockets.

Also move the check out of line and cleanup the messages
that were printed.

Signed-off-by: Arun Sharma <asharma@fb.com>
Suggested-by: Mohan Srinivasan <mohan@fb.com>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: David Miller <davem@davemloft.net>
Cc: Glauber Costa <glommer@parallels.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/tcp.h b/include/net/tcp.h
index d49db0113a069d4b085ffb62d413d5983cfb2445..42c29bfbcee34d8d6ada5d18533850d82973f352 100644 (file)
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -273,6 +273,14 @@ static inline int between(__u32 seq1, __u32 seq2, __u32 seq3)
        return seq3 - seq2 >= seq1 - seq2;
 }
 
+static inline bool tcp_out_of_memory(struct sock *sk)
+{
+       if (sk->sk_wmem_queued > SOCK_MIN_SNDBUF &&
+           sk_memory_allocated(sk) > sk_prot_mem_limits(sk, 2))
+               return true;
+       return false;
+}
+
 static inline bool tcp_too_many_orphans(struct sock *sk, int shift)
 {
        struct percpu_counter *ocp = sk->sk_prot->orphan_count;
@@ -283,13 +291,11 @@ static inline bool tcp_too_many_orphans(struct sock *sk, int shift)
                if (orphans << shift > sysctl_tcp_max_orphans)
                        return true;
        }
-
-       if (sk->sk_wmem_queued > SOCK_MIN_SNDBUF &&
-           sk_memory_allocated(sk) > sk_prot_mem_limits(sk, 2))
-               return true;
        return false;
 }
 
+extern bool tcp_check_oom(struct sock *sk, int shift);
+
 /* syncookies: remember time of last synqueue overflow */
 static inline void tcp_synq_overflow(struct sock *sk)
 {

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 06373b4a449a158451d3c99ec482b80e65a0ab87..a34f5cfdd44c25bcfd7dfc8af4037454c65c946d 100644 (file)
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1876,6 +1876,20 @@ void tcp_shutdown(struct sock *sk, int how)
 }
 EXPORT_SYMBOL(tcp_shutdown);
 
+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);
+       out_of_socket_memory = tcp_out_of_memory(sk);
+
+       if (too_many_orphans && net_ratelimit())
+               pr_info("TCP: too many orphaned sockets\n");
+       if (out_of_socket_memory && net_ratelimit())
+               pr_info("TCP: out of memory -- consider tuning tcp_mem\n");
+       return too_many_orphans || out_of_socket_memory;
+}
+
 void tcp_close(struct sock *sk, long timeout)
 {
        struct sk_buff *skb;
@@ -2015,10 +2029,7 @@ adjudge_to_death:
        }
        if (sk->sk_state != TCP_CLOSE) {
                sk_mem_reclaim(sk);
-               if (tcp_too_many_orphans(sk, 0)) {
-                       if (net_ratelimit())
-                               printk(KERN_INFO "TCP: too many of orphaned "
-                                      "sockets\n");
+               if (tcp_check_oom(sk, 0)) {
                        tcp_set_state(sk, TCP_CLOSE);
                        tcp_send_active_reset(sk, GFP_ATOMIC);
                        NET_INC_STATS_BH(sock_net(sk),

diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index a516d1e399dfcb1a22ca39e452f3dbe725455ade..cd2e0723266d12b508569be0f4f6836cb21f94e7 100644 (file)
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -77,10 +77,7 @@ static int tcp_out_of_resources(struct sock *sk, int do_reset)
        if (sk->sk_err_soft)
                shift++;
 
-       if (tcp_too_many_orphans(sk, shift)) {
-               if (net_ratelimit())
-                       printk(KERN_INFO "Out of socket memory\n");
-
+       if (tcp_check_oom(sk, shift)) {
                /* Catch exceptional cases, when connection requires reset.
                 *      1. Last segment was sent recently. */
                if ((s32)(tcp_time_stamp - tp->lsndtime) <= TCP_TIMEWAIT_LEN ||