Re: [PATCH] proc: show locks in /proc/pid/fdinfo/X

From: Cyrill Gorcunov <gorcunov@gmail.com>
To: Andrey Vagin <avagin@openvz.org>
Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	linux-doc@vger.kernel.org, Jonathan Corbet <corbet@lwn.net>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	Jeff Layton <jlayton@poochiereds.net>,
	"J. Bruce Fields" <bfields@fieldses.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Pavel Emelyanov <xemul@parallels.com>
Subject: Re: [PATCH] proc: show locks in /proc/pid/fdinfo/X
Date: Fri, 6 Mar 2015 11:38:05 +0300	[thread overview]
Message-ID: <20150306083805.GD2263@moon> (raw)
In-Reply-To: <1425569838-20416-1-git-send-email-avagin@openvz.org>

On Thu, Mar 05, 2015 at 06:37:18PM +0300, Andrey Vagin wrote:
> Let's show locks which are associated with a file descriptor in
> its fdinfo file.
> 
> Currently we don't have a reliable way to determine who holds a lock.
> We can find some information in /proc/locks, but PID which is reported
> there can be wrong. For example, a process takes a lock, then forks a
> child and dies. In this case /proc/locks contains the parent pid, which
> can be reused by another process.
> 
> $ cat /proc/locks
> ...
> 6: FLOCK  ADVISORY  WRITE 324 00:13:13431 0 EOF
> ...
> 
> $ ps -C rpcbind
>   PID TTY          TIME CMD
>   332 ?        00:00:00 rpcbind
> 
...

Looks reasonable to me, thanks!
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>