Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751727Ab3GXNqh (ORCPT ); Wed, 24 Jul 2013 09:46:37 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:40337 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750933Ab3GXNqf (ORCPT ); Wed, 24 Jul 2013 09:46:35 -0400 Date: Wed, 24 Jul 2013 09:46:22 -0400 From: Konrad Rzeszutek Wilk To: Zhenzhong Duan Cc: linux-pci@vger.kernel.org, "linux-kernel@vger.kernel.org" , xen-devel , bhelgaas@google.com, Feng Jin , Sucheta Chakraborty Subject: Re: [PATCH 2/3] Refactor msi/msix restore code Part2 Message-ID: <20130724134622.GC2518@phenom.dumpdata.com> References: <51EF451A.8050003@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <51EF451A.8050003@oracle.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: acsinet22.oracle.com [141.146.126.238] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3491 Lines: 104 On Wed, Jul 24, 2013 at 11:08:10AM +0800, Zhenzhong Duan wrote: > xen_initdom_restore_msi_irqs trigger a hypercall to restore addr/data/mask > in dom0. It's better to do the same for default_restore_msi_irqs in baremetal. > > Move restore of mask in default_restore_msi_irqs, this could avoid mask > restored twice in dom0, once in hypercall, the other in kernel. Why not remove the hypercall then? Or alter the function to detect whether the restore of the mask has occurred? > > Without that, qlcnic driver calling pci_reset_function will lost interrupt > in dom0. > > Tested-by: Sucheta Chakraborty > Signed-off-by: Zhenzhong Duan > --- > drivers/pci/msi.c | 17 ++++++++++++++--- > 1 files changed, 14 insertions(+), 3 deletions(-) > > diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c > index 87223ae..922fb49 100644 > --- a/drivers/pci/msi.c > +++ b/drivers/pci/msi.c > @@ -216,6 +216,8 @@ void unmask_msi_irq(struct irq_data *data) > #ifdef HAVE_DEFAULT_MSI_RESTORE_IRQS > void default_restore_msi_irqs(struct pci_dev *dev, int irq) > { > + int pos; > + u16 control; > struct msi_desc *entry; > > entry = NULL; > @@ -228,8 +230,19 @@ void default_restore_msi_irqs(struct pci_dev *dev, int irq) > entry = irq_get_msi_desc(irq); > } > > - if (entry) > + if (entry) { > write_msi_msg(irq, &entry->msg); > + if (dev->msix_enabled) { > + msix_mask_irq(entry, entry->masked); > + readl(entry->mask_base); > + } else { > + pos = entry->msi_attrib.pos; > + pci_read_config_word(dev, pos + PCI_MSI_FLAGS, > + &control); > + msi_mask_irq(entry, msi_capable_mask(control), > + entry->masked); > + } > + } > } > #endif > > @@ -406,7 +419,6 @@ static void __pci_restore_msi_state(struct pci_dev *dev) > arch_restore_msi_irqs(dev, dev->irq); > > pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control); > - msi_mask_irq(entry, msi_capable_mask(control), entry->masked); Before this patch we had: write_msi_msg(..) pci_read_config_work(PCI_MSI_FLAGS, &control) pci_write_config_dword(~msi_capable_mask(control) | entry->masked) control &= ~_PCI_MSI_FLAGS_QSIZE; control |= ... pci_write_config_dword(PCI_MSI_FLAGS, control) while with this you have now: write_msi_msg(..) pci_read_config_work(PCI_MSI_FLAGS, &_control) pci_write_config_dword(~msi_capable_mask(_control) | entry->masked) --> pci_read_config_work(PCI_MSI_FLAGS, &control) control &= ~_PCI_MSI_FLAGS_QSIZE; control |= ... pci_write_config_dword(PCI_MSI_FLAGS, control) see the problem? The 'control' value in __pci_restore_msi_state reads the value _after_ it has been masked (which is now done in default_restore_msi_irqs). Wouldn't that cause problems? > control &= ~PCI_MSI_FLAGS_QSIZE; > control |= (entry->msi_attrib.multiple << 4) | PCI_MSI_FLAGS_ENABLE; > pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control); > @@ -430,7 +442,6 @@ static void __pci_restore_msix_state(struct pci_dev *dev) > > list_for_each_entry(entry, &dev->msi_list, list) { > arch_restore_msi_irqs(dev, entry->irq); > - msix_mask_irq(entry, entry->masked); > } > > control &= ~PCI_MSIX_FLAGS_MASKALL; > -- > 1.7.3 > -- 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/