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Date: Wed, 5 Aug 2009 09:11:40 -0700
Message-ID: <6599ad830908050911t6f23f810i65fe8fe17f3ee698@mail.gmail.com>
Subject: Re: [PATCH 6/6] Makes procs file writable to move all threads by tgid 
	at once
From: Paul Menage <menage@google.com>
To: Paul Menage <menage@google.com>, Benjamin Blum <bblum@google.com>,
       containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
       akpm@linux-foundation.org
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On Wed, Aug 5, 2009 at 3:20 AM, Louis Rilling<Louis.Rilling@kerlabs.com> wrote:
>
> The downside of this is teaching lockdep about this recursive locking. Not that
> simple actually...

Don't we just give each thread's lock its own lock class? That's what
we did for the cgroup hierarchy_mutex.

> so that such cases are currently handled using a higher-level
> lock that prevents races in locking the whole chain (there was one such example
> for locking all vmas with KVM). IIUC, the intent here is to avoid such
> higher-level lock.

cgroup_mutex already fulfills the role of the higher-level lock.

Paul