From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:2210 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754566Ab3JHHzs (ORCPT ); Tue, 8 Oct 2013 03:55:48 -0400 Date: Tue, 8 Oct 2013 09:56:59 +0200 From: Alexander Gordeev To: Tejun Heo Cc: linux-kernel@vger.kernel.org, Bjorn Helgaas , Ralf Baechle , Michael Ellerman , Benjamin Herrenschmidt , Martin Schwidefsky , Ingo Molnar , Dan Williams , Andy King , Jon Mason , Matt Porter , linux-pci@vger.kernel.org, linux-mips@linux-mips.org, linuxppc-dev@lists.ozlabs.org, linux390@de.ibm.com, linux-s390@vger.kernel.org, x86@kernel.org, linux-ide@vger.kernel.org, iss_storagedev@hp.com, linux-nvme@lists.infradead.org, linux-rdma@vger.kernel.org, netdev@vger.kernel.org, e1000-devel@lists.sourceforge.net, linux-driver@qlogic.com, Solarflare linux maintainers , "VMware, Inc." , linux-scsi@vger.kernel.org Subject: Re: [PATCH RFC 05/77] PCI/MSI: Convert pci_msix_table_size() to a public interface Message-ID: <20131008075658.GE10669@dhcp-26-207.brq.redhat.com> References: <20131007181043.GA27396@htj.dyndns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20131007181043.GA27396@htj.dyndns.org> Sender: linux-pci-owner@vger.kernel.org List-ID: On Mon, Oct 07, 2013 at 02:10:43PM -0400, Tejun Heo wrote: > On Wed, Oct 02, 2013 at 12:48:21PM +0200, Alexander Gordeev wrote: > > Make pci_msix_table_size() to return a error code if the device > > does not support MSI-X. This update is needed to facilitate a > > forthcoming re-design MSI/MSI-X interrupts enabling pattern. > > > > Device drivers will use this interface to obtain maximum number > > of MSI-X interrupts the device supports and use that value in > > the following call to pci_enable_msix() interface. > > Hmmm... I probably missed something but why is this necessary? To > discern between -EINVAL and -ENOSPC? If so, does that really matter? pci_msix_table_size() is kind of helper and returns 0 if a device does not have MSI-X table. If we want drivers to use it we need return -EINVAL for MSI-X incapable/disabled devices. Nothing about -ENOSPC. > tejun -- Regards, Alexander Gordeev agordeev@redhat.com