From owner-freebsd-net@FreeBSD.ORG Wed Aug 21 16:38:54 2013 Return-Path: Delivered-To: freebsd-net@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 19BB4D48; Wed, 21 Aug 2013 16:38:54 +0000 (UTC) (envelope-from nparhar@gmail.com) Received: from mail-pd0-x233.google.com (mail-pd0-x233.google.com [IPv6:2607:f8b0:400e:c02::233]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id D51D8286D; Wed, 21 Aug 2013 16:38:53 +0000 (UTC) Received: by mail-pd0-f179.google.com with SMTP id v10so642220pde.24 for ; Wed, 21 Aug 2013 09:38:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; bh=0BaJzeWwOAtERSTpKcWJ+/6YLC+LI0MiLigdI2syJk8=; b=TAhH/NFombUzciYBVWHiZAkc4zr9l850nLTFdAxZPG/VfqUxUY5Q1TbVPt1Xn6GEmp NU3SI6qMppueoRRtSRa4go5tDxE8U9othESQiHjESrVQQgRL5d4gnMXPy6r+YxNM1vkK yMiqX2Ij/4u8hLJ19k6hjWiVKyOj0ukLofiOLEHXAEr9LG/hmBtiPyjyvBvciWtQw9YR do2ZdQyufy7i2Vb/QC2dSegdyMvH8k/LJtPzrznoVPMxnvKZRl6Ph6nS47cbAFihAiSg gmmj7CguXAVqb19AMk+ZIHJyy2/O1p5XiXQt1zM6UJ8BuKA+Z/BZylfNn4XsqEaCt7Ol bB8g== X-Received: by 10.66.248.161 with SMTP id yn1mr10606337pac.0.1377103133500; Wed, 21 Aug 2013 09:38:53 -0700 (PDT) Received: from [10.192.166.0] (stargate.chelsio.com. [67.207.112.58]) by mx.google.com with ESMTPSA id vz4sm11145045pab.11.1969.12.31.16.00.00 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 21 Aug 2013 09:38:52 -0700 (PDT) Sender: Navdeep Parhar Message-ID: <5214ED19.40907@FreeBSD.org> Date: Wed, 21 Aug 2013 09:38:49 -0700 From: Navdeep Parhar User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:17.0) Gecko/20130819 Thunderbird/17.0.8 MIME-Version: 1.0 To: Andre Oppermann Subject: Re: M_NOFREE removal (was Re: svn commit: r254520 - in head/sys: kern sys) References: <201308191116.r7JBGsc6065793@svn.freebsd.org> <521256CE.6070706@FreeBSD.org> <5212587A.2080202@freebsd.org> <52128937.1010407@freebsd.org> <52129E55.30803@freebsd.org> <5214D7E8.1080106@freebsd.org> In-Reply-To: <5214D7E8.1080106@freebsd.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: svn-src-head@freebsd.org, freebsd-net@freebsd.org, Peter Grehan X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 21 Aug 2013 16:38:54 -0000 On 08/21/13 08:08, Andre Oppermann wrote: > On 20.08.2013 00:38, Peter Grehan wrote: > >> If there's an alternative to M_NOFREE, I'd be more than happy to use >> that. > > Set up your own (*ext_free) function and omit freeing of the mbuf > itself. Make > sure to properly track your mbufs to avoid leaking them. > How is this an alternate to M_NOFREE? Your suggestion indicates that you may have removed M_NOFREE thinking it did something other than what it actually did. And this suggestion doesn't even work -- note the uma_zfree(zone_mbuf, m) at the end of mb_free_ext that would run after any custom ext_free. To recap: M_NOFREE was the way to tell the mbuf subsystem that the mbuf does not come from zone_mbuf. Nothing more and nothing less. The mbuf was in other ways like any other mbuf and could have a pkthdr (or not), internal storage (or not), external cluster (or not), etc. etc. Regards, Navdeep