From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vladimir Davydov Subject: [PATCH] fs: super: do not cacheline align s_{inode,dentry}_lru Date: Mon, 19 Jan 2015 15:29:23 +0300 Message-ID: <1421670563-28228-1-git-send-email-vdavydov@parallels.com> Mime-Version: 1.0 Content-Type: text/plain Cc: , To: Alexander Viro Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org super_block->s_{inode,dentry}_lru were made cacheline aligned, because the list_lru struct had a spinlock and a list embedded to it and therefore could be actively modified. Today, struct list_lru is, in fact, read-only: the lists and locks live in list_lru_node's, which list_lru points to. The list_lru_node struct is already cacheline aligned by definition. So let us drop the cacheline aligned annotation in order not to waste space in struct super_block. Signed-off-by: Vladimir Davydov --- include/linux/fs.h | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/include/linux/fs.h b/include/linux/fs.h index 0bd9669ce91d..790e534adbc7 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1309,12 +1309,9 @@ struct super_block { struct workqueue_struct *s_dio_done_wq; struct hlist_head s_pins; - /* - * Keep the lru lists last in the structure so they always sit on their - * own individual cachelines. - */ - struct list_lru s_dentry_lru ____cacheline_aligned_in_smp; - struct list_lru s_inode_lru ____cacheline_aligned_in_smp; + struct list_lru s_dentry_lru; + struct list_lru s_inode_lru; + struct rcu_head rcu; /* -- 1.7.10.4