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Subject: Re: [PATCH 1/2] Enable SPU switch notification to detect currently
	active SPU tasks.
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Christoph Hellwig <hch@lst.de>
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Date: Fri, 13 Jul 2007 22:34:50 +1000
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> > +		if (unlikely(test_bit(SPU_SCHED_NOTIFY_ACTIVE,
> > +				      &ctx->sched_flags))) {
> > +			clear_bit(SPU_SCHED_NOTIFY_ACTIVE, &ctx->sched_flags);
> 
> this should use test_and_clear_bit

This also looks like an abuse of atomics to effectively implement a lock
or did I miss something ?

Ben.