From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e28smtp06.in.ibm.com ([122.248.162.6]:34682 "EHLO e28smtp06.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751066Ab2DAIir (ORCPT ); Sun, 1 Apr 2012 04:38:47 -0400 Received: from /spool/local by e28smtp06.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Sun, 1 Apr 2012 14:08:40 +0530 Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay01.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q318cbCl4366568 for ; Sun, 1 Apr 2012 14:08:38 +0530 Received: from d28av04.in.ibm.com (loopback [127.0.0.1]) by d28av04.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q31E8Q1O001562 for ; Mon, 2 Apr 2012 00:08:26 +1000 Received: from localhost ([9.123.247.55]) by d28av04.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id q31E8Prm001544 for ; Mon, 2 Apr 2012 00:08:25 +1000 Date: Sun, 1 Apr 2012 16:38:35 +0800 From: Richard Yang To: linux-pci@vger.kernel.org Subject: What is the difference between number and secondary in pci_bus? Message-ID: <20120401083835.GA23662@richard> Reply-To: Richard Yang MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-pci-owner@vger.kernel.org List-ID: All In the structure of pci_bus. There is number, primary, secondary and subordinate. primary and subordinate are easy to understand, while the number and secondary confused me. I think secondary means the current bus number. Then what number stands for? In pci_alloc_child_bus(), child->number = child->secondary = busnr; So they are the same? Then we need two different field? I search the git log while find these code is imported as the first commit. So I don't see the history. -- Richard Yang Help you, Help me