[NET]: use __read_mostly on kmem_cache_t , DEFINE_SNMP_STAT pointers
This patch puts mostly read only data in the right section
(read_mostly), to help sharing of these data between CPUS without
memory ping pongs.
On one of my production machine, tcp_statistics was sitting in a
heavily modified cache line, so *every* SNMP update had to force a
reload.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index 7d8ec65..e7025be 100644
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -62,7 +62,7 @@
/* Global data structures. */
struct sctp_globals sctp_globals;
struct proc_dir_entry *proc_net_sctp;
-DEFINE_SNMP_STAT(struct sctp_mib, sctp_statistics);
+DEFINE_SNMP_STAT(struct sctp_mib, sctp_statistics) __read_mostly;
struct idr sctp_assocs_id;
DEFINE_SPINLOCK(sctp_assocs_id_lock);
@@ -78,8 +78,8 @@
static struct sctp_af *sctp_af_v4_specific;
static struct sctp_af *sctp_af_v6_specific;
-kmem_cache_t *sctp_chunk_cachep;
-kmem_cache_t *sctp_bucket_cachep;
+kmem_cache_t *sctp_chunk_cachep __read_mostly;
+kmem_cache_t *sctp_bucket_cachep __read_mostly;
extern int sctp_snmp_proc_init(void);
extern int sctp_snmp_proc_exit(void);