From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH 2/3] [VLAN]: Update iif when receiving via VLAN device Date: Thu, 29 Jun 2006 17:12:15 -0700 (PDT) Message-ID: <20060629.171215.112621072.davem@davemloft.net> References: <20060629233933.GB14627@postel.suug.ch> <20060629.164732.41636454.davem@davemloft.net> <1151626099.8922.64.camel@jzny2> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, kaber@trash.net, tgraf@suug.ch Return-path: Received: from dsl027-180-168.sfo1.dsl.speakeasy.net ([216.27.180.168]:60085 "EHLO sunset.davemloft.net") by vger.kernel.org with ESMTP id S933158AbWF3AMS (ORCPT ); Thu, 29 Jun 2006 20:12:18 -0400 To: hadi@cyberus.ca In-Reply-To: <1151626099.8922.64.camel@jzny2> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: jamal Date: Thu, 29 Jun 2006 20:08:19 -0400 > What am i missing? > on 64bit machine, does it not save 32 bits to use an ifindex as opposed > to the pointer? The objects around it are pointers, which are 64-bit, and thus the 32-bit object gets padded out to 64-bits in the layout of the struct so that the next pointer member can be properly aligned. It does not change the size of sk_buff at all. > Yes, it is a bug, but: > dev_hold/put dont work anymore? why do you need an ifindex instead? You sure you want to do that atomic operation on every single input packet, regardless of whether egresss operations are using it or not? We should put the cost of features at the actual users, and not impose it upon everyone.