From owner-freebsd-current Mon Mar 27 9:32: 1 2000 Delivered-To: freebsd-current@freebsd.org Received: from apollo.backplane.com (apollo.backplane.com [216.240.41.2]) by hub.freebsd.org (Postfix) with ESMTP id 6DE0C37BB18 for ; Mon, 27 Mar 2000 09:31:58 -0800 (PST) (envelope-from dillon@apollo.backplane.com) Received: (from dillon@localhost) by apollo.backplane.com (8.9.3/8.9.1) id JAA41585; Mon, 27 Mar 2000 09:31:54 -0800 (PST) (envelope-from dillon) Date: Mon, 27 Mar 2000 09:31:54 -0800 (PST) From: Matthew Dillon Message-Id: <200003271731.JAA41585@apollo.backplane.com> To: Daniel Eischen Cc: nms@otdel-1.org, freebsd-current@FreeBSD.ORG Subject: Re: Is there spinlocks/semaphores available for drivers? References: Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG :> *not* preempted except when being interrupted, so there are no :> 'priorities', per say. Or, rather, the relative priority is strictly :> that the interrupt takes priority over supervisor code except when :> disabled by said supervisor code. : :But locks with owners wouldn't have to disable interrupts (given that :we have interrupt threads). What about shared interrupts? You could :still field and process the interrupt as long as it was for a different :device. :Dan Eischen The word 'too bad' comes to mind re: shared interrupts. That is, while it would be nice to support concurrent operation in that case, the current model can't, and the customer can simply rearrange his PCI cards if two high-volume devices wind up on the same interrupt to get around the limitation. So making this work would be a very low priority relative to other bullets. -Matt Matthew Dillon To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message