Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751553Ab3IFNPs (ORCPT ); Fri, 6 Sep 2013 09:15:48 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35055 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750704Ab3IFNPp (ORCPT ); Fri, 6 Sep 2013 09:15:45 -0400 Date: Fri, 6 Sep 2013 15:17:40 +0200 From: Alexander Gordeev To: Tejun Heo Cc: linux-kernel@vger.kernel.org, x86@kernel.org, linux-pci@vger.kernel.org, linux-ide@vger.kernel.org, Ingo Molnar , Joerg Roedel , Jan Beulich , Bjorn Helgaas Subject: Re: [PATCH v2 2/6] PCI/MSI: Factor out pci_get_msi_cap() interface Message-ID: <20130906131739.GA27922@dhcp-26-207.brq.redhat.com> References: <20130905130902.GA26314@htj.dyndns.org> <20130905150259.GA30984@dhcp-26-207.brq.redhat.com> <20130905150442.GA24148@htj.dyndns.org> <20130905154041.GD30984@dhcp-26-207.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130905154041.GD30984@dhcp-26-207.brq.redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1131 Lines: 24 On Thu, Sep 05, 2013 at 05:40:41PM +0200, Alexander Gordeev wrote: > On Thu, Sep 05, 2013 at 11:04:42AM -0400, Tejun Heo wrote: > > The thing is, do we even have cases where arch code returns positive > > return to indicate possible partial allocation? If not, the whole > > interface is convoluted for no good reason and we can just make > > everything return 0 or -errno, which is a lot simpler. No? > > As I mentioned in my other note, at least PPC has a concept of MSI quota, > so exceeding it would be the very case, I believe. An update here. No other arch supports multiple MSIs besides Intel (+IOMMU). Yet, ironically, the concept of possible partial allocation was adopted from MSI-X. I briefly checked all archs and it seems none of them throws out a possible other number of MSIs > 1 (including PPC I mistakenly read). -- Regards, Alexander Gordeev agordeev@redhat.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/