net: Use a percpu_counter for sockets_allocated
Instead of using one atomic_t per protocol, use a percpu_counter
for "sockets_allocated", to reduce cache line contention on
heavy duty network servers.
Note : We revert commit (248969ae31e1b3276fc4399d67ce29a5d81e6fd9
net: af_unix can make unix_nr_socks visbile in /proc),
since it is not anymore used after sock_prot_inuse_add() addition
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
index 2379750..bbb7742 100644
--- a/include/net/sctp/sctp.h
+++ b/include/net/sctp/sctp.h
@@ -138,6 +138,7 @@
unsigned int sctp_poll(struct file *file, struct socket *sock,
poll_table *wait);
void sctp_sock_rfree(struct sk_buff *skb);
+extern struct percpu_counter sctp_sockets_allocated;
/*
* sctp/primitive.c
diff --git a/include/net/sock.h b/include/net/sock.h
index 00cd486..a2a3890 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -649,7 +649,7 @@
/* Memory pressure */
void (*enter_memory_pressure)(struct sock *sk);
atomic_t *memory_allocated; /* Current allocated memory. */
- atomic_t *sockets_allocated; /* Current number of sockets. */
+ struct percpu_counter *sockets_allocated; /* Current number of sockets. */
/*
* Pressure flag: try to collapse.
* Technical note: it is used by multiple contexts non atomically.
diff --git a/include/net/tcp.h b/include/net/tcp.h
index e8ae90a..cbca3b8 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -238,7 +238,7 @@
extern int sysctl_tcp_max_ssthresh;
extern atomic_t tcp_memory_allocated;
-extern atomic_t tcp_sockets_allocated;
+extern struct percpu_counter tcp_sockets_allocated;
extern int tcp_memory_pressure;
/*