From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:60346) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UfWjv-0001oH-2u for qemu-devel@nongnu.org; Thu, 23 May 2013 10:43:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UfWjq-0001nn-QD for qemu-devel@nongnu.org; Thu, 23 May 2013 10:43:35 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46970) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UfWfH-0008RA-0m for qemu-devel@nongnu.org; Thu, 23 May 2013 10:38:47 -0400 Date: Thu, 23 May 2013 17:39:06 +0300 From: "Michael S. Tsirkin" Message-ID: <20130523143905.GB24037@redhat.com> References: <1368059472-25071-1-git-send-email-david@gibson.dropbear.id.au> <1368059472-25071-7-git-send-email-david@gibson.dropbear.id.au> <20130523110157.GA17480@redhat.com> <20130523121613.GB26259@boomeroo.fritz.box> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130523121613.GB26259@boomeroo.fritz.box> Subject: Re: [Qemu-devel] [PATCH 6/8] pci: Simpler implementation of primary PCI bus List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: David Gibson Cc: aliguori@us.ibm.com, qemu-devel@nongnu.org On Thu, May 23, 2013 at 10:16:13PM +1000, David Gibson wrote: > On Thu, May 23, 2013 at 02:01:57PM +0300, Michael S. Tsirkin wrote: > > On Thu, May 09, 2013 at 10:31:10AM +1000, David Gibson wrote: > > > Currently pci_get_primary_bus() searches the list of root buses for one > > > with domain 0. But since host buses are always registered with domain 0, > > > this just amounts to finding the only PCI host bus. > > > > > > This simplifies the implementation by defining the primary PCI bus to > > > be the first one registered, using a global variable to track it. > > > > > > Signed-off-by: David Gibson > > > > This is the only part that I dislike. > > How about an explicit API to set the primary bus? > > Let machine types set it. > > I guess, though I was hoping to avoid changing every bit of platform > code that sets up a PCI bus. Yes, that's a lot of churn. Maybe we don't need a primary bus at all? If there's one root, it's simple: check it's the only one and return. > -- > David Gibson | I'll have my music baroque, and my code > david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ > | _way_ _around_! > http://www.ozlabs.org/~dgibson