From owner-svn-src-head@FreeBSD.ORG Sat Jul 27 07:48:05 2013 Return-Path: Delivered-To: svn-src-head@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 4067112B; Sat, 27 Jul 2013 07:48:05 +0000 (UTC) (envelope-from brde@optusnet.com.au) Received: from mail108.syd.optusnet.com.au (mail108.syd.optusnet.com.au [211.29.132.59]) by mx1.freebsd.org (Postfix) with ESMTP id C7A3B2B5C; Sat, 27 Jul 2013 07:48:03 +0000 (UTC) Received: from c122-106-156-23.carlnfd1.nsw.optusnet.com.au (c122-106-156-23.carlnfd1.nsw.optusnet.com.au [122.106.156.23]) by mail108.syd.optusnet.com.au (Postfix) with ESMTPS id 66DD91A3524; Sat, 27 Jul 2013 17:47:53 +1000 (EST) Date: Sat, 27 Jul 2013 17:47:52 +1000 (EST) From: Bruce Evans X-X-Sender: bde@besplex.bde.org To: Juli Mallett Subject: Re: svn commit: r253662 - in head: lib/libc/gen sys/vm tools/tools/sysdoc In-Reply-To: Message-ID: <20130727170845.E872@besplex.bde.org> References: <201307260200.r6Q207cB015223@svn.freebsd.org> <20130726150949.GC14175@stack.nl> <51F2E970.3070303@FreeBSD.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Optus-CM-Score: 0 X-Optus-CM-Analysis: v=2.1 cv=Yos2GeoX c=1 sm=1 tr=0 a=ebeQFi2P/qHVC0Yw9JDJ4g==:117 a=PO7r1zJSAAAA:8 a=NRP33-gIz6cA:10 a=kj9zAlcOel0A:10 a=JzwRw_2MAAAA:8 a=csUvqbbglXYA:10 a=6I5d2MoRAAAA:8 a=V2Xkxio-15NM_JPYHrYA:9 a=CjuIK1q_8ugA:10 a=SV7veod9ZcQA:10 Cc: svn-src-head@FreeBSD.org, Andrey Zonov , src-committers@FreeBSD.org, svn-src-all@FreeBSD.org, Jilles Tjoelker X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 27 Jul 2013 07:48:05 -0000 On Fri, 26 Jul 2013, Juli Mallett wrote: > On Fri, Jul 26, 2013 at 2:26 PM, Andrey Zonov wrote: > >> On 7/26/13 8:09 AM, Jilles Tjoelker wrote: >>> As noted in mail from Bruce Evans, please preserve the ABI of >>> VM_SWAPPING_ENABLED here. >> >> I don't think it's a big problem. Internally we don't use it. Good >> code uses sysctlbyname() instead of sysctl(). It doesn't seem to me >> this is very popular sysctl. It's also CURRENT without MFC. > > That doesn't seem like a great argument. > > Why should we break the ABI for bad code that used that sysctl and all > following? It seems pretty trivial to preserve, and no-cost. Also, the > fact that it's in current misses the point completely: it breaks ABI with > older binaries, namely older binaries running on -CURRENT. And not just > for that field. Especially since the main reason numbered sysctls exist is to support old binaries (and sources) that use them. Bruce