From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta12.messagelabs.com (mail6.bemta12.messagelabs.com [216.82.250.247]) by kanga.kvack.org (Postfix) with ESMTP id 130BA6B0012 for ; Sun, 29 May 2011 16:39:43 -0400 (EDT) Received: from unknown (HELO localhost.localdomain) (zcndxNqBwcve2s/KpKWToZWJlF6Wp6IuYnI=@[201.23.160.70]) (envelope-sender ) by smtp-02.mandic.com.br (qmail-ldap-1.03) with AES256-SHA encrypted SMTP for ; 29 May 2011 20:39:36 -0000 From: Cesar Eduardo Barros Subject: [PATCH] cleancache: use __read_mostly for cleancache_enabled Date: Sun, 29 May 2011 17:38:18 -0300 Message-Id: <1306701498-10846-1-git-send-email-cesarb@cesarb.net> Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org Cc: Minchan Kim , Jan Beulich , Andrew Morton , Andreas Dilger , Dan Magenheimer , Jeremy Fitzhardinge , linux-kernel@vger.kernel.org, Cesar Eduardo Barros The global variable cleancache_enabled is read often but written to rarely. Use __read_mostly to prevent it being on the same cacheline as another variable which is written to often, which would cause cacheline bouncing. Signed-off-by: Cesar Eduardo Barros --- include/linux/cleancache.h | 2 +- mm/cleancache.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/include/linux/cleancache.h b/include/linux/cleancache.h index 04ffb2e..83fffe8 100644 --- a/include/linux/cleancache.h +++ b/include/linux/cleancache.h @@ -42,7 +42,7 @@ extern void __cleancache_put_page(struct page *); extern void __cleancache_flush_page(struct address_space *, struct page *); extern void __cleancache_flush_inode(struct address_space *); extern void __cleancache_flush_fs(struct super_block *); -extern int cleancache_enabled; +extern int cleancache_enabled __read_mostly; #ifdef CONFIG_CLEANCACHE static inline bool cleancache_fs_enabled(struct page *page) diff --git a/mm/cleancache.c b/mm/cleancache.c index bcaae4c..a3d7a22 100644 --- a/mm/cleancache.c +++ b/mm/cleancache.c @@ -24,7 +24,7 @@ * disabled), so is preferred to the slower alternative: a function * call that checks a non-global. */ -int cleancache_enabled; +int cleancache_enabled __read_mostly; EXPORT_SYMBOL(cleancache_enabled); /* -- 1.7.4.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org