From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Gortmaker Subject: [PATCH net-next 7/9] tipc: add __read_mostly annotations to several global variables Date: Thu, 16 Aug 2012 18:09:12 -0400 Message-ID: <1345154954-12526-8-git-send-email-paul.gortmaker@windriver.com> References: <1345154954-12526-1-git-send-email-paul.gortmaker@windriver.com> Cc: netdev@vger.kernel.org, Jon Maloy , Ying Xue , Paul Gortmaker To: David Miller Return-path: Received: from mail.windriver.com ([147.11.1.11]:57503 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752661Ab2HPWOy (ORCPT ); Thu, 16 Aug 2012 18:14:54 -0400 In-Reply-To: <1345154954-12526-1-git-send-email-paul.gortmaker@windriver.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Ying Xue 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 Signed-off-by: Jon Maloy Signed-off-by: Paul Gortmaker --- 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