From owner-freebsd-net  Tue Dec 12  1:44:34 2000
From owner-freebsd-net@FreeBSD.ORG  Tue Dec 12 01:44:32 2000
Return-Path: <owner-freebsd-net@FreeBSD.ORG>
Delivered-To: freebsd-net@freebsd.org
Received: from fw.wintelcom.net (ns1.wintelcom.net [209.1.153.20])
	by hub.freebsd.org (Postfix) with ESMTP
	id 52D8E37B400; Tue, 12 Dec 2000 01:44:32 -0800 (PST)
Received: (from bright@localhost)
	by fw.wintelcom.net (8.10.0/8.10.0) id eBC9iUq03639;
	Tue, 12 Dec 2000 01:44:30 -0800 (PST)
Date: Tue, 12 Dec 2000 01:44:30 -0800
From: Alfred Perlstein <bright@wintelcom.net>
To: Bosko Milekic <bmilekic@technokratis.com>
Cc: net@FreeBSD.ORG, jhb@FreeBSD.ORG, jasone@FreeBSD.ORG
Subject: MEXT_IS_REF broken.
Message-ID: <20001212014429.Y16205@fw.wintelcom.net>
References: <20001211014837.W16205@fw.wintelcom.net> <Pine.BSF.4.21.0012111223350.21769-100000@jehovah.technokratis.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
User-Agent: Mutt/1.2.5i
In-Reply-To: <Pine.BSF.4.21.0012111223350.21769-100000@jehovah.technokratis.com>; from bmilekic@technokratis.com on Mon, Dec 11, 2000 at 12:44:55PM -0500
Sender: bright@fw.wintelcom.net
Sender: owner-freebsd-net@FreeBSD.ORG
Precedence: bulk
X-Loop: FreeBSD.org

grr...

considering this:

#define MEXT_IS_REF(m) ((m)->m_ext.ref_cnt->refcnt > 1)

#define MEXT_REM_REF(m) do {                        \
    KASSERT((m)->m_ext.ref_cnt->refcnt > 0, ("m_ext refcnt < 0"));  \
    atomic_subtract_long(&((m)->m_ext.ref_cnt->refcnt), 1);     \
} while(0)

this:

#define MEXTFREE(m) do {                        \
    struct mbuf *_mmm = (m);                    \
                                    \
    if (MEXT_IS_REF(_mmm))                      \
        MEXT_REM_REF(_mmm);                 \

 
is not mpsafe.  we _NEED_ some type that allows atomic dec and test
for 0.

thanks,
-Alfred


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-net" in the body of the message