From owner-freebsd-arch@FreeBSD.ORG Wed Jul 10 06:44:14 2013 Return-Path: Delivered-To: freebsd-arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 0D8EF94F for ; Wed, 10 Jul 2013 06:44:14 +0000 (UTC) (envelope-from peter@wemm.org) Received: from mail-vc0-x234.google.com (mail-vc0-x234.google.com [IPv6:2607:f8b0:400c:c03::234]) by mx1.freebsd.org (Postfix) with ESMTP id C2696178A for ; Wed, 10 Jul 2013 06:44:13 +0000 (UTC) Received: by mail-vc0-f180.google.com with SMTP id gf11so5036340vcb.11 for ; Tue, 09 Jul 2013 23:44:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=wemm.org; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=5KdcLwtWEsrPrz3L5/CkeEZo/iw9texiUl5ix1tS6Jw=; b=1v/g8RfbaYV5/1N/KQknWozwK1rHgL1VfUy49YpMg5jZfSfcryFdjM4ktYPutOe0zv WnuIP7WMJvongSXqHEWRWpYG1qj+L+hOw+0+CRl3K5/sQPb4tvqdL8f6YvBelCW2Nu/q lroE/RZmi0kSoBWKCzAFWMvYvzE+/CN5vHN8M= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:x-gm-message-state; bh=5KdcLwtWEsrPrz3L5/CkeEZo/iw9texiUl5ix1tS6Jw=; b=FHh0tzmpl+kSZNNHfO879O0ixrhpSF65H6XyM/PtaV3se3hFPQ312AoLeNWGULKmEG UHUy0pMmo+w6BMxnkIAneTYrJHCEKPixIGyoWxdnPvB8c92XsaHAloqwjqXSqFy3tGd5 RuD2tn4ksL+tmLBR6ZQnC2XZbh1jqv4Zvl3Y3WG88UqDtK7CKOT4rEaSmBkwzL8oXB67 h4elmeSM+CqTeSr6dqSh3qxhpWhCX3oY4Y71Y8YDU89tgmk67to1ETII8UYfhnvjz5/o uNhNbwZEoiDM4TzULq8spciDNNJHV/0MQlhDM65+kcKJ5IwTJuAHZ63s/n019ytSmzgy MtsA== MIME-Version: 1.0 X-Received: by 10.52.65.111 with SMTP id w15mr14839784vds.73.1373438653298; Tue, 09 Jul 2013 23:44:13 -0700 (PDT) Received: by 10.221.37.198 with HTTP; Tue, 9 Jul 2013 23:44:13 -0700 (PDT) In-Reply-To: <20130710063406.GA39842@gmail.com> References: <20130709185846.GA19508@gmail.com> <20130709211657.GA86400@stack.nl> <20130710063406.GA39842@gmail.com> Date: Tue, 9 Jul 2013 23:44:13 -0700 Message-ID: Subject: Re: ABI change in libkvm (kvm_uread removal) From: Peter Wemm To: Mikolaj Golub Content-Type: text/plain; charset=ISO-8859-1 X-Gm-Message-State: ALoCoQkJOLx1E6LcFKc7gcDQcgvO3YwmyaJlfA1wtdF92yrF1jts6ClyJRrrWrrfzEIfEDFzZL2X Cc: freebsd-arch@freebsd.org, Jilles Tjoelker , Robert Millan X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 10 Jul 2013 06:44:14 -0000 On Tue, Jul 9, 2013 at 11:34 PM, Mikolaj Golub wrote: > On Tue, Jul 09, 2013 at 11:16:57PM +0200, Jilles Tjoelker wrote: >> On Tue, Jul 09, 2013 at 09:59:19PM +0300, Mikolaj Golub wrote: >> > Suggestions how this should be fixed properly (if possible) are highly >> > appreciated. I will do what people suggest. >> >> I would suggest bringing back kvm_uread() in stable/9 so that the ABI is >> kept. In head, I suggest removing kvm_uread() from the header file and >> bumping the soname. I think MFCing the soname bump will cause more >> annoyance than the removal of kvm_uread() itself. >> >> Much of the code using libkvm uses it to access kernel internals, which >> are not a proper ABI/API and change fairly frequently. Therefore, it is >> probably acceptable for this library not to use symbol versioning. >> >> The functions that do not expose the caller to kernel internals like >> kvm_getprocs() should probably not be used; instead, libprocstat >> provides a more ABI-stable way to do the same. Calling the sysctls >> directly is also an option. > > Thank you all for your suggestions. I like Jilles' the most. So I am > going to return kvm_uread back to stable/9 by a direct commit and > remove it entirely from head and bump soname. Have you confirmed that the code you're about to add back actually works? -- Peter Wemm - peter@wemm.org; peter@FreeBSD.org; peter@yahoo-inc.com; KI6FJV UTF-8: So you can \342\200\231 .. for when a ' just won't do ZFS must be the bacon of file systems. "everything's better with ZFS"