From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jared Hulbert" <jaredeh@gmail.com>
Subject: Re: [PATCH 04/10] AXFS: axfs_inode.c
Date: Thu, 21 Aug 2008 08:06:50 -0700
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References: <48AD00F0.5030403@gmail.com> <200808211417.14425.arnd@arndb.de>
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To: Arnd Bergmann <arnd@arndb.de>
Cc: Linux-kernel@vger.kernel.org, linux-embedded@vger.kernel.org, linux-mtd <linux-mtd@lists.infradead.org>, =?UTF-8?Q?J=C3=B6rn_Engel?= <joern@logfs.org>, tim.bird@am.sony.com, cotte@de.ibm.com, nickpiggin@yahoo.com.au

> Have you seen any benefit of the rwsem over a simple mutex? I would guess
> that you can never even get into the situation where you get concurrent
> readers since I haven't found a single down_read() in your code, only
> downgrade_write()

We implemented a rwsem here because you can get concurrent readers.
My understanding is that downgrade_write() puts the rewem into the
same state as down_read().  Am I mistaken?