From: Chris Mason <chris.mason@oracle.com>
To: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <david@fromorbit.com>,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-btrfs@vger.kernel.org
Subject: Re: [PATCH 09/18] fs: rework icount to be a locked variable
Date: Fri, 8 Oct 2010 09:16:54 -0400 [thread overview]
Message-ID: <20101008131654.GJ4804@think> (raw)
In-Reply-To: <20101008081714.GB1728@lst.de>
On Fri, Oct 08, 2010 at 10:17:14AM +0200, Christoph Hellwig wrote:
> On Fri, Oct 08, 2010 at 06:50:01PM +1100, Dave Chinner wrote:
> > > There's no need to lock a normal 32-bit variable for readers.
> >
> > Ok, but will need a memory barrier instead?
>
> Isn't spin_unlock supposed to be one? I'll need some of the locking
> experts to shime in.
Not really a locking expert, but the locking operations are supposed to
have an implicit barrier.
-chris
prev parent reply other threads:[~2010-10-08 13:16 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1286515292-15882-1-git-send-email-david@fromorbit.com>
[not found] ` <1286515292-15882-10-git-send-email-david@fromorbit.com>
2010-10-08 7:27 ` [PATCH 09/18] fs: rework icount to be a locked variable Christoph Hellwig
2010-10-08 7:50 ` Dave Chinner
2010-10-08 8:17 ` Christoph Hellwig
2010-10-08 13:16 ` Chris Mason [this message]
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