Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753979Ab0K0KdQ (ORCPT ); Sat, 27 Nov 2010 05:33:16 -0500 Received: from ipmail04.adl6.internode.on.net ([150.101.137.141]:34780 "EHLO ipmail04.adl6.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752816Ab0K0K0O (ORCPT ); Sat, 27 Nov 2010 05:26:14 -0500 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApcFAO1p8Ex5Lcx2/2dsb2JhbACVC44Acr12hUcEimGFFA Message-Id: <67e25699e4b7780690be65a20912cbbc5d2d33b1.1290852959.git.npiggin@kernel.dk> In-Reply-To: References: From: Nick Piggin Date: Sat, 27 Nov 2010 20:44:53 +1100 Subject: [PATCH 23/46] fs: dcache reduce dcache_inode_lock To: linux-fsdevel@vger.kernel.org Cc: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2249 Lines: 88 dcache_inode_lock can be avoided in d_delete() and d_materialise_unique() in cases where it is not required. Signed-off-by: Nick Piggin --- fs/dcache.c | 24 ++++++++++++------------ 1 files changed, 12 insertions(+), 12 deletions(-) diff --git a/fs/dcache.c b/fs/dcache.c index 3e4f7c1..6fe387d 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1794,10 +1794,15 @@ void d_delete(struct dentry * dentry) /* * Are we the only user? */ - spin_lock(&dcache_inode_lock); +again: spin_lock(&dentry->d_lock); isdir = S_ISDIR(dentry->d_inode->i_mode); if (dentry->d_count == 1) { + if (!spin_trylock(&dcache_inode_lock)) { + spin_unlock(&dentry->d_lock); + cpu_relax(); + goto again; + } dentry->d_flags &= ~DCACHE_CANT_MOUNT; dentry_iput(dentry); fsnotify_nameremove(dentry, isdir); @@ -1808,7 +1813,6 @@ void d_delete(struct dentry * dentry) __d_drop(dentry); spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_inode_lock); fsnotify_nameremove(dentry, isdir); } @@ -2106,14 +2110,15 @@ struct dentry *d_materialise_unique(struct dentry *dentry, struct inode *inode) BUG_ON(!d_unhashed(dentry)); - spin_lock(&dcache_inode_lock); - if (!inode) { actual = dentry; __d_instantiate(dentry, NULL); - goto found_lock; + d_rehash(actual); + goto out_nolock; } + spin_lock(&dcache_inode_lock); + if (S_ISDIR(inode->i_mode)) { struct dentry *alias; @@ -2145,10 +2150,9 @@ struct dentry *d_materialise_unique(struct dentry *dentry, struct inode *inode) actual = __d_instantiate_unique(dentry, inode); if (!actual) actual = dentry; - else if (unlikely(!d_unhashed(actual))) - goto shouldnt_be_hashed; + else + BUG_ON(!d_unhashed(actual)); -found_lock: spin_lock(&actual->d_lock); found: spin_lock(&dcache_hash_lock); @@ -2164,10 +2168,6 @@ out_nolock: iput(inode); return actual; - -shouldnt_be_hashed: - spin_unlock(&dcache_inode_lock); - BUG(); } EXPORT_SYMBOL_GPL(d_materialise_unique); -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/