Re: [PATCH 09/18] fs: rework icount to be a locked variable

Chris Mason
2010-10-08T13:18:41Z

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