From owner-freebsd-current@FreeBSD.ORG Wed Mar 18 15:19:22 2015 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id A95FB6C2; Wed, 18 Mar 2015 15:19:22 +0000 (UTC) Received: from mail-ig0-x233.google.com (mail-ig0-x233.google.com [IPv6:2607:f8b0:4001:c05::233]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 6E6649D0; Wed, 18 Mar 2015 15:19:22 +0000 (UTC) Received: by igbue6 with SMTP id ue6so102916249igb.1; Wed, 18 Mar 2015 08:19:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=q8L/EsaH71tkVW6MYQxb6FQ0Ow3QSs3iMIBXc7d7UbE=; b=bY4u/6ZaEEwpanKH610k1ouUfXoV8BduWB/IoH7YJVKDIqd3qMDnhIC5hS0wMz6+Ul dYXhqR5PCR5Zzu5LckTXNJ59oGN28AXXxFXhGwsC/NQjemsSNjV3wkA0tefilK22cXpy rVLLQzOLl8oVMsd7aSI/1a+GDBdNFkXu10m8CDFtiZjgZn/Hf0XCtdTIjEJ9gwJviuTz vMLCgpM5nSKkeQWdWnmpZujAo00qp+3rH7u2i9HG4b7c4WLWftpwjNbmYGDFHN1g6KpD QESG8P7B7FcPavVobP7apw4yN51n8SY3Qq+dALOX9KcN+eJsJ+K3VKfLn0WH80IJOGp4 oxdA== MIME-Version: 1.0 X-Received: by 10.50.39.65 with SMTP id n1mr7696138igk.37.1426691961857; Wed, 18 Mar 2015 08:19:21 -0700 (PDT) Received: by 10.107.156.75 with HTTP; Wed, 18 Mar 2015 08:19:21 -0700 (PDT) In-Reply-To: <2085699.T9kJlc0rkf@ralph.baldwin.cx> References: <2085699.T9kJlc0rkf@ralph.baldwin.cx> Date: Wed, 18 Mar 2015 11:19:21 -0400 Message-ID: Subject: Re: What parts of UMA are part of the stable ABI? From: Ryan Stone To: John Baldwin Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.18-1 Cc: FreeBSD Current X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 18 Mar 2015 15:19:22 -0000 On Wed, Mar 18, 2015 at 10:24 AM, John Baldwin wrote: > I do think the normal zone callbacks passed to uma_zcreate() are too public > to change. Or at least, you would need to do some crazy ABI shim where you > have a uma_zcreate_new() that you map to uma_zcreate() via a #define for > the API, but include a legacy uma_zcreate() symbol that older modules can > call (and then somehow tag the old function pointers via an internal flag > in the zone and patch UMA to cast to the old function signatures for zones > with that flag). > I really wasn't clear here. I definitely don't think that changing the ctor, etc to accept a size_t is MFC'able, and I don't think that the problem (which is really only theoretical at this point) warrants an MFC to -stable. I was talking about potentially doing it in a separate commit to head, but that does leave -stable and head with a different API. This can be painful for downstream consumers to deal with, which is why I wanted comments.