From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bart De Schuymer <bdschuym@pandora.be>
Subject: Re: [PATCH/RFC] Reduce call chain length in netfilter
Date: Thu, 27 Jan 2005 22:16:04 +0100
Message-ID: <1106860564.3389.4.camel@localhost.localdomain>
References: <1131604877.20041218092730@mail.ru.suse.lists.linux.kernel>
	 <p73zn0ccaee.fsf@verdi.suse.de>
	 <1105117559.11753.34.camel@baythorne.infradead.org>
	 <20050107100017.454ddadc@dxpl.pdx.osdl.net>
	 <1105133241.3375.16.camel@localhost.localdomain>
	 <20050118135735.4b77d38d.davem@davemloft.net>
	 <1106433059.4486.11.camel@localhost.localdomain>
	 <1106436153.20995.42.camel@tux.rsn.bth.se>
	 <1106484019.3376.5.camel@localhost.localdomain>
	 <1106496509.1085.1.camel@tux.rsn.bth.se>
	 <20050125220558.6e824f8a.davem@davemloft.net>
	 <1106730510.4041.4.camel@localhost.localdomain>
	 <41F82C6D.7020006@trash.net> <20050126231801.7bf90338.davem@davemloft.net>
	 <41F929FA.3050800@trash.net>  <20050127114726.2205b4ed.davem@davemloft.net>
Mime-Version: 1.0
Content-Type: text/plain
Content-Transfer-Encoding: 7bit
Cc: Patrick McHardy <kaber@trash.net>, netdev@oss.sgi.com,
        netfilter-devel@lists.netfilter.org, snort2004@mail.ru,
        rusty@rustcorp.com.au, ak@suse.de, bridge@osdl.org,
        gandalf@wlug.westbo.se, dwmw2@infradead.org, shemminger@osdl.org
Return-path: <netdev-bounce@oss.sgi.com>
To: "David S. Miller" <davem@davemloft.net>
In-Reply-To: <20050127114726.2205b4ed.davem@davemloft.net>
Sender: netdev-bounce@oss.sgi.com
Errors-to: netdev-bounce@oss.sgi.com
List-Id: netdev.vger.kernel.org

Op do, 27-01-2005 te 11:47 -0800, schreef David S. Miller:
> On Thu, 27 Jan 2005 18:50:50 +0100
> Patrick McHardy <kaber@trash.net> wrote:
> 
> >  From what I can see it doesn't generate tail-calls currently:
> 
> Indeed... It even doesn't do this on Sparc64 either, even for
> the okfn(skb) call which I was sure it would.
> 
> It won't tail-call for function pointers for some strance reason
> as exhibited by this simple test:
> 
> struct sk_buff {
> 	int foo;
> };
> 
> int invoke(struct sk_buff *skb, int (*okfn)(struct sk_buff *))
> {
> 	return okfn(skb);
> }
> 
> extern int test_func(struct sk_buff *);
> 
> int invoke2(struct sk_buff *skb)
> {
> 	return test_func(skb);
> }
> 
> In the generated asm on sparc64, invoke2() gets a tail-call
> whereas invoke() does not.  Hmmm...

Pasha (<snort2004@mail.ru>) is currently using a bridge-nf patch vs
2.4.29 with the changes I sent to you. After two days he sent me
(yesterday) a message that all is well. Without the patch he was getting
the stack overflow oopses.

cheers,
Bart