From owner-freebsd-net@FreeBSD.ORG Tue Feb 17 10:26:06 2009 Return-Path: Delivered-To: net@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 6530D1065712; Tue, 17 Feb 2009 10:26:06 +0000 (UTC) (envelope-from rwatson@FreeBSD.org) Received: from cyrus.watson.org (cyrus.watson.org [65.122.17.42]) by mx1.freebsd.org (Postfix) with ESMTP id 3F47C8FC1C; Tue, 17 Feb 2009 10:26:06 +0000 (UTC) (envelope-from rwatson@FreeBSD.org) Received: from fledge.watson.org (fledge.watson.org [65.122.17.41]) by cyrus.watson.org (Postfix) with ESMTPS id D048446B35; Tue, 17 Feb 2009 05:26:05 -0500 (EST) Date: Tue, 17 Feb 2009 10:26:05 +0000 (GMT) From: Robert Watson X-X-Sender: robert@fledge.watson.org To: Krassimir Slavchev In-Reply-To: <499A884A.4040408@bulinfo.net> Message-ID: References: <20080526110543.J26343@fledge.watson.org> <4999F7F9.4030204@elischer.org> <499A884A.4040408@bulinfo.net> User-Agent: Alpine 2.00 (BSF 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: net@FreeBSD.org, Julian Elischer , current@FreeBSD.org Subject: Re: HEADS UP: IFF_NEEDSGIANT consumers to be disabled, removed X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 17 Feb 2009 10:26:08 -0000 On Tue, 17 Feb 2009, Krassimir Slavchev wrote: >> if_sr and if_ar are really simple and could probably be converted >> "trivially".. especially if their netgraph code is used. >> >> however I wonder if anyone still has that hardware (they are drivers for >> two sync serial cards). > > I still have such Digi/Arnet SYNC/570i PCI card and I used to use it for a > long time with 4.x and if_ar driver without any problems. > > Thanks to John Hay for well written driver! I would be quite happy to see the remaining drivers be converted over -- when using IFF_NEEDSGIANT, they do potentially see a significant performance loss as a result of having to defer execution to Giant-holding contexts. However, the sooner the better, as stripping the Giant compat stuff will allow us to clean up the compat shims, in turn removing the need for deferred execution to avoid calling those shims in unfortunate contexts for multicast, and simplifies the forthcoming address list locking work. Robert N M Watson Computer Laboratory University of Cambridge