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From: Bodo Eggert <7eggert@gmx.de>
To: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp>, akpm@linux-foundation.org,
       linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
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Date: Tue, 16 Sep 2008 17:32:08 +0200
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Subject: Re: [PATCH] VFS: make file->f_pos access atomic on 32bit arch
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Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp> wrote:

> Protecting file->f_pos with a lock adds some overhead but I think we should
> fix this.
> I used seqlock to serialize the access to file->f_pos. This approach is
> similar to inode->i_size synchronization.
> 
> Comments?

> +             if (offset != file_pos_read(file))
> +                     file_pos_write(file, offset);

Maybe file_pos_write should do this check?