From: Louis Rilling Date: Fri, 15 Aug 2008 19:37:23 +0000 (-0700) Subject: [PATCH] configfs: Consolidate locking around configfs_detach_prep() in configfs_rmdir() X-Git-Tag: v2.6.27-rc5~20^2~1 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=de6bf18e9ce0df807dab08cff08751cac383429d;p=linux-2.6-omap-h63xx.git [PATCH] configfs: Consolidate locking around configfs_detach_prep() in configfs_rmdir() It appears that configfs_rmdir() can protect configfs_detach_prep() retries with less calls to {spin,mutex}_{lock,unlock}, and a cleaner code. This patch does not change any behavior, except that it removes two useless lock/unlock pairs having nothing inside to protect and providing a useless barrier. Signed-off-by: Louis Rilling Signed-off-by: Joel Becker Signed-off-by: Mark Fasheh --- diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c index 7a8db78a91d..8e93341f3e8 100644 --- a/fs/configfs/dir.c +++ b/fs/configfs/dir.c @@ -1311,16 +1311,18 @@ static int configfs_rmdir(struct inode *dir, struct dentry *dentry) * Ensure that no racing symlink() will make detach_prep() fail while * the new link is temporarily attached */ - mutex_lock(&configfs_symlink_mutex); - spin_lock(&configfs_dirent_lock); do { struct mutex *wait_mutex; + mutex_lock(&configfs_symlink_mutex); + spin_lock(&configfs_dirent_lock); ret = configfs_detach_prep(dentry, &wait_mutex); - if (ret) { + if (ret) configfs_detach_rollback(dentry); - spin_unlock(&configfs_dirent_lock); - mutex_unlock(&configfs_symlink_mutex); + spin_unlock(&configfs_dirent_lock); + mutex_unlock(&configfs_symlink_mutex); + + if (ret) { if (ret != -EAGAIN) { config_item_put(parent_item); return ret; @@ -1329,13 +1331,8 @@ static int configfs_rmdir(struct inode *dir, struct dentry *dentry) /* Wait until the racing operation terminates */ mutex_lock(wait_mutex); mutex_unlock(wait_mutex); - - mutex_lock(&configfs_symlink_mutex); - spin_lock(&configfs_dirent_lock); } } while (ret == -EAGAIN); - spin_unlock(&configfs_dirent_lock); - mutex_unlock(&configfs_symlink_mutex); /* Get a working ref for the duration of this function */ item = configfs_get_config_item(dentry);