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authorEric Dumazet <dada1@cosmosbay.com>2007-03-27 13:58:31 -0700
committerDavid S. Miller <davem@sunset.davemloft.net>2007-04-25 22:28:19 -0700
commit4103f8cd5c1f260d674a7b426ed221812de54d47 (patch)
tree28649757907dd77b53a8c16533c963c43fea4be0
parent73417f617a93cf30342c3ea41abc38927bd467aa (diff)
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[TCP]: tcp_memory_pressure and tcp_socket are__read_mostly candidates
tcp_memory_pressure and tcp_socket currently share a cache line with tcp_memory_allocated, tcp_sockets_allocated. (Very hot cache line) It makes sense to declare these variables as __read_mostly, to avoid false sharing on SMP. ffffffff8081d9c0 B tcp_orphan_count ffffffff8081d9c4 B tcp_memory_allocated ffffffff8081d9c8 B tcp_sockets_allocated ffffffff8081d9cc B tcp_memory_pressure ffffffff8081d9d0 b tcp_md5sig_users ffffffff8081d9d8 b tcp_md5sig_pool ffffffff8081d9e0 b warntime.31570 ffffffff8081d9e8 b tcp_socket Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--net/ipv4/tcp.c2
-rw-r--r--net/ipv4/tcp_ipv4.c2
2 files changed, 2 insertions, 2 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 18a09a78ca0b..bb9d91a7662f 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -297,7 +297,7 @@ EXPORT_SYMBOL(tcp_sockets_allocated);
* All the sk_stream_mem_schedule() is of this nature: accounting
* is strict, actions are advisory and have some latency.
*/
-int tcp_memory_pressure;
+int tcp_memory_pressure __read_mostly;
EXPORT_SYMBOL(tcp_memory_pressure);
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 617a5e4ca010..e11eaf4cc269 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -88,7 +88,7 @@ int sysctl_tcp_low_latency __read_mostly;
#define ICMP_MIN_LENGTH 8
/* Socket used for sending RSTs */
-static struct socket *tcp_socket;
+static struct socket *tcp_socket __read_mostly;
void tcp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb);