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David Alan Gilbert" , Eric Auger , Kirti Wankhede , qemu-arm@nongnu.org, yuzenghui@huawei.com, wanghaibin.wang@huawei.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, 9 Mar 2021 15:25:52 +0800 Shenming Lu wrote: > On 2021/3/3 5:26, Alex Williamson wrote: > > > > MST/Marcel, > > > > Do you have an Ack or objection to exporting msix_masked() as below? > > Or could we use msix_function_masked instead as below? :-) > > if (!pdev->msix_function_masked) { > for (nr = 0; nr < msix_nr_vectors_allocated(pdev); nr++) { > if (!msix_is_masked(pdev, nr)) { > max_vec = nr; > } > } > } Yeah, it looks like that should work. I'll look for a v4 with that change. Thanks, Alex > > On Tue, 23 Feb 2021 10:22:25 +0800 > > Shenming Lu wrote: > > > >> In VFIO migration resume phase and some guest startups, there are > >> already unmasked vectors in the vector table when calling > >> vfio_msix_enable(). So in order to avoid inefficiently disabling > >> and enabling vectors repeatedly, let's allocate all needed vectors > >> first and then enable these unmasked vectors one by one without > >> disabling. > >> > >> Signed-off-by: Shenming Lu > >> --- > >> hw/pci/msix.c | 2 +- > >> hw/vfio/pci.c | 20 +++++++++++++++++--- > >> include/hw/pci/msix.h | 1 + > >> 3 files changed, 19 insertions(+), 4 deletions(-) > >> > >> diff --git a/hw/pci/msix.c b/hw/pci/msix.c > >> index ae9331cd0b..e057958fcd 100644 > >> --- a/hw/pci/msix.c > >> +++ b/hw/pci/msix.c > >> @@ -131,7 +131,7 @@ static void msix_handle_mask_update(PCIDevice *dev, int vector, bool was_masked) > >> } > >> } > >> > >> -static bool msix_masked(PCIDevice *dev) > >> +bool msix_masked(PCIDevice *dev) > >> { > >> return dev->config[dev->msix_cap + MSIX_CONTROL_OFFSET] & MSIX_MASKALL_MASK; > >> } > >> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c > >> index f74be78209..088fd41926 100644 > >> --- a/hw/vfio/pci.c > >> +++ b/hw/vfio/pci.c > >> @@ -569,6 +569,9 @@ static void vfio_msix_vector_release(PCIDevice *pdev, unsigned int nr) > >> > >> static void vfio_msix_enable(VFIOPCIDevice *vdev) > >> { > >> + PCIDevice *pdev = &vdev->pdev; > >> + unsigned int nr, max_vec = 0; > >> + > >> vfio_disable_interrupts(vdev); > >> > >> vdev->msi_vectors = g_new0(VFIOMSIVector, vdev->msix->entries); > >> @@ -587,11 +590,22 @@ static void vfio_msix_enable(VFIOPCIDevice *vdev) > >> * triggering to userspace, then immediately release the vector, leaving > >> * the physical device with no vectors enabled, but MSI-X enabled, just > >> * like the guest view. > >> + * If there are already unmasked vectors (in migration resume phase and > >> + * some guest startups) which will be enabled soon, we can allocate all > >> + * of them here to avoid inefficiently disabling and enabling vectors > >> + * repeatedly later. > >> */ > >> - vfio_msix_vector_do_use(&vdev->pdev, 0, NULL, NULL); > >> - vfio_msix_vector_release(&vdev->pdev, 0); > >> + if (!msix_masked(pdev)) { > >> + for (nr = 0; nr < msix_nr_vectors_allocated(pdev); nr++) { > >> + if (!msix_is_masked(pdev, nr)) { > >> + max_vec = nr; > >> + } > >> + } > >> + } > >> + vfio_msix_vector_do_use(pdev, max_vec, NULL, NULL); > >> + vfio_msix_vector_release(pdev, max_vec); > >> > >> - if (msix_set_vector_notifiers(&vdev->pdev, vfio_msix_vector_use, > >> + if (msix_set_vector_notifiers(pdev, vfio_msix_vector_use, > >> vfio_msix_vector_release, NULL)) { > >> error_report("vfio: msix_set_vector_notifiers failed"); > >> } > >> diff --git a/include/hw/pci/msix.h b/include/hw/pci/msix.h > >> index 4c4a60c739..b3cd88e262 100644 > >> --- a/include/hw/pci/msix.h > >> +++ b/include/hw/pci/msix.h > >> @@ -28,6 +28,7 @@ void msix_load(PCIDevice *dev, QEMUFile *f); > >> > >> int msix_enabled(PCIDevice *dev); > >> int msix_present(PCIDevice *dev); > >> +bool msix_masked(PCIDevice *dev); > >> > >> bool msix_is_masked(PCIDevice *dev, unsigned vector); > >> void msix_set_pending(PCIDevice *dev, unsigned vector); > > > > . > > >