svn: warning: 'xxxxxx' is already under version control

[root@NGINX-APACHE-SVN pm]# svn status
?       plugins
?       files
?       images
?       data
?       resources
[root@NGINX-APACHE-SVN pm]# svn add plugins/
svn: warning: 'plugins' is already under version control

[root@NGINX-APACHE-SVN pm]# ls -all plugins/
total 28
drwxr-xr-x 7 root root 4096 Aug  6 01:43 .
drwxr-xr-x 8 root root 4096 Aug  6 01:43 ..
drwxr-xr-x 4 root root 4096 Aug  6 01:43 debug
drwxr-xr-x 4 root root 4096 Aug  6 01:43 page_notes
drwxr-xr-x 4 root root 4096 Aug  6 01:43 recordplay
drwxr-xr-x 4 root root 4096 Aug  6 01:43 sitemap
drwxr-xr-x 6 root root 4096 Aug  6 01:54 .svn

删除.svn文件就可以了！！