From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935641Ab3FTC5t (ORCPT ); Wed, 19 Jun 2013 22:57:49 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:29676 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935534Ab3FTC5r (ORCPT ); Wed, 19 Jun 2013 22:57:47 -0400 Message-ID: <51C26F98.8070103@oracle.com> Date: Thu, 20 Jun 2013 10:57:28 +0800 From: Zhenzhong Duan Reply-To: zhenzhong.duan@oracle.com Organization: oracle User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:17.0) Gecko/20130509 Thunderbird/17.0.6 MIME-Version: 1.0 To: Stefano Stabellini CC: Konrad Rzeszutek Wilk , David Vrabel , "xen-devel@lists.xensource.com" , Feng Jin , Yuval Shaia , "linux-kernel@vger.kernel.org" , Chien Yen , Ingo Molnar , "H. Peter Anvin" , Thomas Gleixner Subject: Re: [Xen-devel] [PATCH] xen: reuse the same pirq allocated when driver load first time References: <20130513182055.GC14177@phenom.dumpdata.com> <20130514142013.GA10173@konrad-lan.dumpdata.com> <5195944A.3050608@oracle.com> <20130520175706.GA27973@phenom.dumpdata.com> <20130520203855.GA30616@phenom.dumpdata.com> <519B474E.4000202@citrix.com> <20130521134059.GE492@phenom.dumpdata.com> <51AECC3A.7060803@oracle.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Source-IP: acsinet21.oracle.com [141.146.126.237] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2013-06-05 20:50, Stefano Stabellini wrote: > On Wed, 5 Jun 2013, Zhenzhong Duan wrote: >> Stefano Stabellini wrote: >> >> On Tue, 21 May 2013, Stefano Stabellini wrote: >> >> >> On Tue, 21 May 2013, Konrad Rzeszutek Wilk wrote: >> >> >> Looking at the hypervisor code I couldn't see anything obviously wrong. >> >> >> I think the culprit is "physdev_unmap_pirq": >> >> if ( is_hvm_domain(d) ) >> { >> spin_lock(&d->event_lock); >> gdprintk(XENLOG_WARNING,"d%d, pirq: %d is %x %s, irq: %d\n", >> d->domain_id, pirq, domain_pirq_to_emuirq(d, pirq), >> domain_pirq_to_emuirq(d, pirq) == IRQ_UNBOUND ? "unbound" : "", >> domain_pirq_to_irq(d, pirq)); >> >> if ( domain_pirq_to_emuirq(d, pirq) != IRQ_UNBOUND ) >> ret = unmap_domain_pirq_emuirq(d, pirq); >> spin_unlock(&d->event_lock); >> if ( domid == DOMID_SELF || ret ) >> goto free_domain; >> >> It always tells me unbound: >> >> (XEN) physdev.c:237:d14 14, pirq: 54 is ffffffff >> (XEN) irq.c:1873:d14 14, nr_pirqs: 56 >> (XEN) physdev.c:237:d14 14, pirq: 53 is ffffffff >> (XEN) irq.c:1873:d14 14, nr_pirqs: 56 >> (XEN) physdev.c:237:d14 14, pirq: 52 is ffffffff >> (XEN) irq.c:1873:d14 14, nr_pirqs: 56 >> (XEN) physdev.c:237:d14 14, pirq: 51 is ffffffff >> (XEN) irq.c:1873:d14 14, nr_pirqs: 56 >> (XEN) physdev.c:237:d14 14, pirq: 50 is ffffffff >> (XEN) irq.c:1873:d14 14, nr_pirqs: 56 >> (a bit older debug code, so the 'unbound' does not show up here). >> >> Which means that the call to unmap_domain_pirq_emuirq does not happen. >> The checks in unmap_domain_pirq_emuirq also look to be depend >> on the code being IRQ_UNBOUND. >> >> In other words, all of that code looks to only clear things when >> they are !IRQ_UNBOUND. >> >> But the other logic (IRQ_UNBOUND) looks to be missing a removal >> in the radix tree: >> >> if ( emuirq != IRQ_PT ) >> radix_tree_delete(&d->arch.hvm_domain.emuirq_pirq, emuirq); >> >> And I think that is what is causing the leak - the radix tree >> needs to be pruned? Or perhaps the allocate_pirq should check >> the radix tree for IRQ_UNBOUND ones and re-use them? >> >> >> I think that you are looking in the wrong place. >> The issue is that QEMU doesn't call pt_msi_disable in >> pt_msgctrl_reg_write if (!val & PCI_MSI_FLAGS_ENABLE). >> >> The code above is correct as is because it is trying to handle emulated >> IRQs and MSIs, not real passthrough MSIs. They latter are not added to >> that radix tree, see physdev_hvm_map_pirq and physdev_map_pirq. >> >> >> >> This patch fixes the issue, I have only tested MSI (MSI-X completely >> untested). >> >> >> diff --git a/hw/pass-through.c b/hw/pass-through.c >> index 304c438..079e465 100644 >> --- a/hw/pass-through.c >> +++ b/hw/pass-through.c >> @@ -3866,7 +3866,11 @@ static int pt_msgctrl_reg_write(struct pt_dev *ptdev, >> ptdev->msi->flags |= PCI_MSI_FLAGS_ENABLE; >> } >> else >> - ptdev->msi->flags &= ~PCI_MSI_FLAGS_ENABLE; >> + { >> + if (ptdev->msi->flags & PT_MSI_MAPPED) { >> + pt_msi_disable(ptdev); >> + } >> + } >> >> /* pass through MSI_ENABLE bit when no MSI-INTx translation */ >> if (!ptdev->msi_trans_en) { >> @@ -4013,6 +4017,8 @@ static int pt_msixctrl_reg_write(struct pt_dev *ptdev, >> pt_disable_msi_translate(ptdev); >> } >> pt_msix_update(ptdev); >> + } else if (!(*value & PCI_MSIX_ENABLE) && ptdev->msix->enabled) { >> + pt_msix_delete(ptdev); >> >> >> Hi Stefano, >> I made a test with this patch, os reboot when driver reload. If use pt_msix_disable >> instead of pt_msix_delete, driver could be reloaded. >> But I still see some error in qemu.log and xen console. Seems four IRQs are not freed >> when unmap. >> --------------first load--------------------------- >> pt_msix_update_one: pt_msix_update_one requested pirq = 103 >> pt_msix_update_one: Update msix entry 0 with pirq 67 gvec 0 >> pt_msix_update_one: pt_msix_update_one requested pirq = 102 >> pt_msix_update_one: Update msix entry 1 with pirq 66 gvec 0 >> pt_msix_update_one: pt_msix_update_one requested pirq = 101 >> pt_msix_update_one: Update msix entry 2 with pirq 65 gvec 0 >> pt_msix_update_one: pt_msix_update_one requested pirq = 100 >> pt_msix_update_one: Update msix entry 3 with pirq 64 gvec 0 >> ------------- first unload--------------------------- >> pt_msix_disable: Unbind msix with pirq 67, gvec 0 >> pt_msix_disable: Unmap msix with pirq 67 >> pt_msix_disable: Error: Unmapping of MSI-X failed. [00:04.0] >> pt_msix_disable: Unbind msix with pirq 66, gvec 0 >> pt_msix_disable: Unmap msix with pirq 66 >> pt_msix_disable: Error: Unmapping of MSI-X failed. [00:04.0] >> pt_msix_disable: Unbind msix with pirq 65, gvec 0 >> pt_msix_disable: Unmap msix with pirq 65 >> pt_msix_disable: Error: Unmapping of MSI-X failed. [00:04.0] >> pt_msix_disable: Unbind msix with pirq 64, gvec 0 >> pt_msix_disable: Unmap msix with pirq 64 >> pt_msix_disable: Error: Unmapping of MSI-X failed. [00:04.0] > Can you add some printks in Xen (the hypercall name is > PHYSDEVOP_unmap_pirq) to figure out exactly why they are failing? Did some test, domain_pirq_to_emuirq(d, unmap->pirq) = IRQ_UNBOUND in physdev_unmap_pirq. zduan