[PATCH net-next 7/9] tipc: add __read_mostly annotations to several global variables
From: Paul Gortmaker <hidden>
Date: 2012-08-16 22:14:54
Subsystem:
networking [general], the rest, tipc network layer · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Jon Maloy
From: Ying Xue <redacted> Added to the following: - tipc_random - tipc_own_addr - tipc_max_ports - tipc_net_id - tipc_remote_management - handler_enabled The above global variables are read often, but written rarely. Use __read_mostly to prevent them being on the same cacheline as another variable which is written to often, which would cause cacheline bouncing. Signed-off-by: Ying Xue <redacted> Signed-off-by: Jon Maloy <redacted> Signed-off-by: Paul Gortmaker <redacted> --- net/tipc/core.c | 10 +++++----- net/tipc/core.h | 10 +++++----- net/tipc/handler.c | 2 +- 3 files changed, 11 insertions(+), 11 deletions(-)
diff --git a/net/tipc/core.c b/net/tipc/core.c
index daae7f7..b858f20 100644
--- a/net/tipc/core.c
+++ b/net/tipc/core.c@@ -48,15 +48,15 @@ /* global variables used by multiple sub-systems within TIPC */ -int tipc_random; +int tipc_random __read_mostly; /* configurable TIPC parameters */ -u32 tipc_own_addr; -int tipc_max_ports; +u32 tipc_own_addr __read_mostly; +int tipc_max_ports __read_mostly; int tipc_max_subscriptions; int tipc_max_publications; -int tipc_net_id; -int tipc_remote_management; +int tipc_net_id __read_mostly; +int tipc_remote_management __read_mostly; /**
diff --git a/net/tipc/core.h b/net/tipc/core.h
index e4e46cd..4c5705a 100644
--- a/net/tipc/core.h
+++ b/net/tipc/core.h@@ -74,17 +74,17 @@ int tipc_snprintf(char *buf, int len, const char *fmt, ...); /* * Global configuration variables */ -extern u32 tipc_own_addr; -extern int tipc_max_ports; +extern u32 tipc_own_addr __read_mostly; +extern int tipc_max_ports __read_mostly; extern int tipc_max_subscriptions; extern int tipc_max_publications; -extern int tipc_net_id; -extern int tipc_remote_management; +extern int tipc_net_id __read_mostly; +extern int tipc_remote_management __read_mostly; /* * Other global variables */ -extern int tipc_random; +extern int tipc_random __read_mostly; /* * Routines available to privileged subsystems
diff --git a/net/tipc/handler.c b/net/tipc/handler.c
index 7a52d39..111ff83 100644
--- a/net/tipc/handler.c
+++ b/net/tipc/handler.c@@ -45,7 +45,7 @@ struct queue_item { static struct kmem_cache *tipc_queue_item_cache; static struct list_head signal_queue_head; static DEFINE_SPINLOCK(qitem_lock); -static int handler_enabled; +static int handler_enabled __read_mostly; static void process_signal_queue(unsigned long dummy);
--
1.7.11.1