From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mouse.start.ca ([64.140.120.56]:47551 "EHLO mouse.start.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756643Ab3IZMsx (ORCPT ); Thu, 26 Sep 2013 08:48:53 -0400 Message-ID: <52442975.9000603@start.ca> Date: Thu, 26 Sep 2013 08:32:53 -0400 From: Mark Lord MIME-Version: 1.0 To: Alexander Gordeev CC: Michael Ellerman , Benjamin Herrenschmidt , Tejun Heo , "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 , linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH v2 2/6] PCI/MSI: Factor out pci_get_msi_cap() interface References: <20130905154041.GD30984@dhcp-26-207.brq.redhat.com> <20130905154436.GC24148@htj.dyndns.org> <20130905185440.GA13175@dhcp-26-207.brq.redhat.com> <20130905200608.GA3846@htj.dyndns.org> <20130906160621.GF22763@mtj.dyndns.org> <20130906233205.GF12956@google.com> <20130909152044.GA24962@dhcp-26-207.brq.redhat.com> <20130916102210.GA14102@dhcp-26-207.brq.redhat.com> <20130917143022.GA7707@concordia> <20130918094759.GA2353@dhcp-26-207.brq.redhat.com> In-Reply-To: <20130918094759.GA2353@dhcp-26-207.brq.redhat.com> Content-Type: text/plain; charset=UTF-8 Sender: linux-pci-owner@vger.kernel.org List-ID: On 13-09-18 05:48 AM, Alexander Gordeev wrote: > > The last pattern makes most of sense to me and could be updated with a more > clear sequence - a call to (bit modified) pci_msix_table_size() followed > by a call to pci_enable_msix(). I think this pattern can effectively > supersede the currently recommended "loop" practice. The loop is still necessary, because there's a race between those two calls, so that pci_enable_msix() can still fail due to lack of MSIX slots.