The patch titled configfs: consolidate locking around configfs_detach_prep() in configfs_rmdir() has been added to the -mm tree. Its filename is configfs-consolidate-locking-around-configfs_detach_prep-in-configfs_rmdir.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: configfs: consolidate locking around configfs_detach_prep() in configfs_rmdir() From: Louis Rilling <louis.rilling@xxxxxxxxxxx> It appears that configfs_rmdir() can protect configfs_detach_prep() retries with less calls to {spin,mutex}_{lock,unlock}, and 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 <louis.rilling@xxxxxxxxxxx> Cc: Joel Becker <Joel.Becker@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/configfs/dir.c | 17 +++++++---------- 1 file changed, 7 insertions(+), 10 deletions(-) diff -puN fs/configfs/dir.c~configfs-consolidate-locking-around-configfs_detach_prep-in-configfs_rmdir fs/configfs/dir.c --- a/fs/configfs/dir.c~configfs-consolidate-locking-around-configfs_detach_prep-in-configfs_rmdir +++ a/fs/configfs/dir.c @@ -1311,16 +1311,18 @@ static int configfs_rmdir(struct inode * * 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 * /* 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); _ Patches currently in -mm which might be from louis.rilling@xxxxxxxxxxx are configfs-consolidate-locking-around-configfs_detach_prep-in-configfs_rmdir.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html