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Message-ID: <bda6d13a0604241424r503d1b87jb44d1df1a11feb3b@mail.gmail.com>
Date: Mon, 24 Apr 2006 14:24:47 -0700
From: "Joshua Hudson" <joshudson@gmail.com>
To: "Pekka Enberg" <penberg@cs.helsinki.fi>, linux-kernel@vger.kernel.org
Subject: Re: Filesystem & mutex
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On 4/24/06, Pekka Enberg <penberg@cs.helsinki.fi> wrote:
> Hi,
>
> On 4/24/06, Joshua Hudson <joshudson@gmail.com> wrote:
> > My filesystem has need of an extra mutex in the extended inode data area.
> > From what I understand, the mutex can be initalized in inode_init_once, but
> > I cannot determine how to free it.
> >
> > It looks wrong to destroy the mutex by just destroying the slab.
> > It is wrong to destroy the inode in destroy_inode. Badness when
> > an inode is reused.
>
> There's no need to 'release' a mutex. If the mutex is unlocked, you
> can do kmem_cache_free() on the owning inode. You need to do
> mutex_init() in the object cache constructor (init_once) only because
> the memory given to you can be arbitrary state. After the mutex has
> been initialized, it will never go into an illegal state on its own
> assuming you remember to unlock it before freeing the inode.
>
>                                             Pekka
Tx. Your solution worked.