From owner-freebsd-arch Thu Jun 20 20:42: 3 2002 Delivered-To: freebsd-arch@freebsd.org Received: from angelica.unixdaemons.com (angelica.unixdaemons.com [209.148.64.135]) by hub.freebsd.org (Postfix) with ESMTP id 6FA1937B412 for ; Thu, 20 Jun 2002 20:41:59 -0700 (PDT) Received: from angelica.unixdaemons.com (bmilekic@localhost.unixdaemons.com [127.0.0.1]) by angelica.unixdaemons.com (8.12.4/8.12.1) with ESMTP id g5L3fl14047809; Thu, 20 Jun 2002 23:41:47 -0400 (EDT) X-Authentication-Warning: angelica.unixdaemons.com: Host bmilekic@localhost.unixdaemons.com [127.0.0.1] claimed to be angelica.unixdaemons.com Received: (from bmilekic@localhost) by angelica.unixdaemons.com (8.12.4/8.12.1/Submit) id g5L3flwh047808; Thu, 20 Jun 2002 23:41:47 -0400 (EDT) (envelope-from bmilekic) Date: Thu, 20 Jun 2002 23:41:47 -0400 From: Bosko Milekic To: Jonathan Lemon Cc: Terry Lambert , Gary Thorpe , freebsd-arch@FreeBSD.ORG Subject: Re: multiple threads for interrupts Message-ID: <20020620234147.A44910@unixdaemons.com> References: <3D1293AE.FDEC441D@mindspring.com> <20020620220712.E70387@prism.flugsvamp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <20020620220712.E70387@prism.flugsvamp.com>; from jlemon@flugsvamp.com on Thu, Jun 20, 2002 at 10:07:12PM -0500 Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Thu, Jun 20, 2002 at 10:07:12PM -0500, Jonathan Lemon wrote: > > Luigi's and Jon Lemon's work only partially mitigates the problem. > > Turning off interrupts doesn't deal with the NETISR triggering, > > which only occurs when you splx() down from a hardware interrupt > > level so that the SWL list is run. Running the packets on partially > > up the stack doesn't resolve the problems up to the user/kernel > > barrier. So both are only partial solutions. > > Yes. The patches (which I should really make an effort to find out > where I put them; maybe to my left under some strawberry jam) were > for -stable, and delivered the packet all the way to the socket buffer > in interrupt context. They were more intended as a proof of concept > than anything else, although I wouldn't have any qualms about committing > them to -stable; the corresponding work has to be done in -current first > though. > > I think that an interesting next step(s) would be to start collapsing > some of the stack layering a bit. The design notes that VJ outlined > for 4.4BSD (which were never completed) look interesting. > -- > Jonathan I think that it's too early to make that assumption. As I mentionned, I did bring it up at the summit so I don't think that it's a totally bad idea. To get back to the topic, I think: 1) the swi pool thread stuff is cool and should go in so that it gets to mature some in the repo. We shouldn't make any big switches to use it for all cases, though, at least not yet. 2) if we decide to do go to higher layers with network interrupts then we'll probably need the pool thread stuff anyway, and we ought to consider various tweaks. I have a feeling that it's just a little too early to make reasonable decisions on how to implement this the Right Way just yet. 3) I'm interesting in what Jeffrey Hsu and Jennifer (Gosh, I hope I got her name right!) think about this, as they're currently working actively on locking down the network code. 4) Hi JLemon! Welcome back! -- Bosko Milekic bmilekic@unixdaemons.com bmilekic@FreeBSD.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message