On Tue, 21 Sep 2021 07:02:01 +0800
"Longpeng(Mike)" <longpe...@huawei.com> wrote:
> Commit ecebe53fe993 ("vfio: Avoid disabling and enabling vectors
> repeatedly in VFIO migration") avoid inefficiently disabling and
s/avoid/avoids/
> enabling vectors repeatedly and let the unmasked vectors to be
s/let/lets/ s/to//
> enabled one by one.
>
> But we want to batch multiple routes and defer the commit, and only
> commit once out side the loop of setting vector notifiers, so we
s/out side/outside/
> cannot to enable the vectors one by one in the loop now.
s/to//
Thanks,
Alex
>
> Revert that commit and we will take another way in the next patch,
> it can not only avoid disabling/enabling vectors repeatedly, but
> also satisfy our requirement of defer to commit.
>
> Signed-off-by: Longpeng(Mike) <longpe...@huawei.com>
> ---
> hw/vfio/pci.c | 20 +++-----------------
> 1 file changed, 3 insertions(+), 17 deletions(-)
>
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index 8fe238b11d..2de1cc5425 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -610,9 +610,6 @@ static __attribute__((unused)) void
> vfio_commit_kvm_msi_virq(VFIOPCIDevice *vdev
>
> 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);
> @@ -631,22 +628,11 @@ 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.
> */
> - if (!pdev->msix_function_masked) {
> - 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);
> + vfio_msix_vector_do_use(&vdev->pdev, 0, NULL, NULL);
> + vfio_msix_vector_release(&vdev->pdev, 0);
>
> - if (msix_set_vector_notifiers(pdev, vfio_msix_vector_use,
> + if (msix_set_vector_notifiers(&vdev->pdev, vfio_msix_vector_use,
> vfio_msix_vector_release, NULL)) {
> error_report("vfio: msix_set_vector_notifiers failed");
> }
