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Message-ID: <961aa3350803110529o61fe42e8q27ab10e0cb8f9bb6@mail.gmail.com>
Date: Tue, 11 Mar 2008 21:29:11 +0900
From: "Akinobu Mita" <akinobu.mita@gmail.com>
To: "Hugh Dickins" <hugh@veritas.com>
Subject: Re: [PATCH 4/5] shmem: use call_once()
Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org,
       linux-fsdevel@vger.kernel.org
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2008/3/11, Hugh Dickins <hugh@veritas.com>:
> On Tue, 11 Mar 2008, Akinobu Mita wrote:
>  > This patch defers mounting tmpfs till shmem_file_setup() is
>  > called first time by using call_once().
>
>
> Please explain why we might need this patch: is something changing
>  elsewhere?  Or are you misled by that "module_init(init_tmpfs)"
>  into thinking that mm/shmem.c is sometimes built modular?
>

If no processes call shmem_file_setup() (via shm_get(2)), it is unnecessary
to do vfs_kern_mount(&tmpfs_fs_type, ...) unconditionary in boot-time.
So I thought it is suitable example to demonstrate how to use "call_once()"
in this patch set.