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Date: Wed, 09 Jul 2008 09:24:42 -0500
From: Christoph Lameter <cl@linux-foundation.org>
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To: Bruno Santos <bsantos@av.it.pt>
CC: Arjan van de Ven <arjan@infradead.org>, linux-kernel@vger.kernel.org
Subject: Re: semaphore: lockless fastpath using atomic_{inc,dec}_return
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And is this safe? It seems that we can always be rescheduled after the atomic operation and
interrupts can occur too. You need to tell us why this is safe in all cases.