Return-Path: <jt@bougret.hpl.hp.com>
Date: Wed, 4 Feb 2004 18:26:35 -0800
To: Marcel Holtmann <marcel@holtmann.org>
Cc: Max Krasnyansky <maxk@qualcomm.com>,
   BlueZ Mailing List <bluez-devel@lists.sourceforge.net>
Subject: Re: L2CAP non-blocking socket nasty race conditions
Message-ID: <20040205022635.GA24757@bougret.hpl.hp.com>
Reply-To: jt@hpl.hp.com
References: <20040204015825.GA2217@bougret.hpl.hp.com> <1075879044.13285.151.camel@pegasus> <20040204175832.GB16590@bougret.hpl.hp.com> <1075924727.2783.47.camel@pegasus> <20040204214541.GA20129@bougret.hpl.hp.com> <1075942818.2783.70.camel@pegasus> <20040205011102.GA23352@bougret.hpl.hp.com> <1075944624.2783.87.camel@pegasus> <20040205014030.GA23802@bougret.hpl.hp.com> <1075947705.2783.117.camel@pegasus>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
In-Reply-To: <1075947705.2783.117.camel@pegasus>
From: Jean Tourrilhes <jt@bougret.hpl.hp.com>
List-ID: <bluez-devel.lists.sourceforge.net>

On Thu, Feb 05, 2004 at 03:21:46AM +0100, Marcel Holtmann wrote:
> Hi Jean,
> 
> right now I don't see an easy way out of it.

	I told you ;-) That's why I didn't send a patch.

> What I am thinking is that
> if our socket is BT_LISTEN, we check for an not empty accept_q and than
> iterate through all sockets for BT_CONNECTED. If we found one, we return
> POLLIN else nothing.

	This is a bit yucky, especially that poll is performance
critical (for scalability). That's why I was suggesting the socket
counter in the parent. Check what's sk_ack_backlog does, it's very
close to what we want.

> Regards
> 
> Marcel

	Jean