From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759411Ab0KPO0O (ORCPT ); Tue, 16 Nov 2010 09:26:14 -0500 Received: from ipmail05.adl6.internode.on.net ([150.101.137.143]:3958 "EHLO ipmail05.adl6.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758645Ab0KPOYB (ORCPT ); Tue, 16 Nov 2010 09:24:01 -0500 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AogKAKMh4kx5Ldur/2dsb2JhbACUX4ECjH1yvmaFSwSKWIUQ Message-Id: <20101116142030.710208884@kernel.dk> User-Agent: quilt/0.48-1 Date: Wed, 17 Nov 2010 01:09:26 +1100 From: Nick Piggin To: linux-fsdevel@vger.kernel.org Cc: linux-kernel@vger.kernel.org Subject: [patch 26/28] fs: reduce dcache_inode_lock width in lru scanning References: <20101116140900.039761100@kernel.dk> Content-Disposition: inline; filename=dcache-lru-scanning-less-lock.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Signed-off-by: Nick Piggin --- fs/dcache.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) Index: linux-2.6/fs/dcache.c =================================================================== --- linux-2.6.orig/fs/dcache.c 2010-11-17 00:52:38.000000000 +1100 +++ linux-2.6/fs/dcache.c 2010-11-17 01:05:37.000000000 +1100 @@ -586,7 +586,7 @@ static void shrink_dentry_list(struct li dentry = list_entry(list->prev, struct dentry, d_lru); if (!spin_trylock(&dentry->d_lock)) { -relock: +relock1: spin_unlock(&dcache_lru_lock); cpu_relax(); spin_lock(&dcache_lru_lock); @@ -603,20 +603,24 @@ static void shrink_dentry_list(struct li spin_unlock(&dentry->d_lock); continue; } + if (!spin_trylock(&dcache_inode_lock)) { +relock2: + spin_unlock(&dentry->d_lock); + goto relock1; + } if (IS_ROOT(dentry)) parent = NULL; else parent = dentry->d_parent; if (parent && !spin_trylock(&parent->d_lock)) { - spin_unlock(&dentry->d_lock); - goto relock; + spin_unlock(&dcache_inode_lock); + goto relock2; } __dentry_lru_del(dentry); spin_unlock(&dcache_lru_lock); prune_one_dentry(dentry, parent); /* dcache_inode_lock and dentry->d_lock dropped */ - spin_lock(&dcache_inode_lock); spin_lock(&dcache_lru_lock); } } @@ -637,7 +641,6 @@ static void __shrink_dcache_sb(struct su LIST_HEAD(tmp); int cnt = *count; - spin_lock(&dcache_inode_lock); relock: spin_lock(&dcache_lru_lock); while (!list_empty(&sb->s_dentry_lru)) { @@ -675,7 +678,6 @@ static void __shrink_dcache_sb(struct su if (!list_empty(&referenced)) list_splice(&referenced, &sb->s_dentry_lru); spin_unlock(&dcache_lru_lock); - spin_unlock(&dcache_inode_lock); } /** @@ -764,14 +766,12 @@ void shrink_dcache_sb(struct super_block { LIST_HEAD(tmp); - spin_lock(&dcache_inode_lock); spin_lock(&dcache_lru_lock); while (!list_empty(&sb->s_dentry_lru)) { list_splice_init(&sb->s_dentry_lru, &tmp); shrink_dentry_list(&tmp); } spin_unlock(&dcache_lru_lock); - spin_unlock(&dcache_inode_lock); } EXPORT_SYMBOL(shrink_dcache_sb);