From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757844AbYF0IiS (ORCPT ); Fri, 27 Jun 2008 04:38:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755474AbYF0IiC (ORCPT ); Fri, 27 Jun 2008 04:38:02 -0400 Received: from rv-out-0506.google.com ([209.85.198.225]:59867 "EHLO rv-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755408AbYF0IiA (ORCPT ); Fri, 27 Jun 2008 04:38:00 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:mime-version:content-type :content-transfer-encoding:content-disposition; b=WrVjkoOgj0TM040w5LHbnsu5suxNeTPQE8JN0q2fKPh7caMT7P0I/uhcI19QqTwV7C 9XZF1EBk1EHImGo+dQGfVhfKjel/nfesmeQEQEVsRtqwUNVooIXi1HR5J8T9ehkIpMnt BlrKmRNLNeyoQ273ZnlB0QWHQ23lRpE+X5t0M= Message-ID: <965f530d0806270137y19c36638yc6ae0a1d4bfa63e7@mail.gmail.com> Date: Fri, 27 Jun 2008 03:37:59 -0500 From: "Kiran Kotla" To: linux-kernel@vger.kernel.org, linux-net@vger.kernel.org Subject: setting ICSK_CA_PRIV_SIZE larger than 16 * sizeof(u32) MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi guys, We have a recently implemented our Congestion control algorithm named PERT (Probabilistic early response TCP), in the linux kernel. As a part of it, we needed to define some variables in the private variables part ( __u32 icsk_ca_priv[16] ) of per flow structure (struct inet_connection_sock) in the file "include/net/inet_connection_sock.h" As you can see the limit on the number of private variables has been imposed to 16 u32 variables. However, our protocol requires that we have more than 16 say upto 25 u32 variables. We tried changing the size of icsk_ca_priv from 16 to a larger value and correspondingly changed the #define ICSK_CA_PRIV_SIZE to a larger value which was initially set to "16 * sizeof(u32)". We have searched the entire kernel code but did not find any other dependency on the size of "icsk_ca_priv". We compiled the code and rebooted the machine with the new image and we see a kernel crash (Panic) at the very piece of code where this structure is being initialized. We reset it back to 16 and it worked perfectly fine. I just wanted to ask if there is a way to change the size of this private variable array "icsk_ca_priv". The only other option we have to get the kernel running with our protocol is to reduce the number of private variables and this is not possible without affecting the behavior of our protocol. It would be great if someone of you who have used this structure sometime shedded light on this. Your replies are very well appreciated. Thanks a ton in advance. best wishes Kiran Kotla