[RFC PATCH 1/8] vfio/pci: Consolidate irq cleanup on MSI/MSI-X disable

From: Reinette Chatre
Date: Wed Mar 15 2023 - 17:00:09 EST


vfio_msi_disable() releases all previously allocated state
associated with each interrupt before disabling MSI/MSI-X.

vfio_msi_disable() iterates twice over the interrupt state:
first directly with a for loop to do virqfd cleanup, followed
by another for loop within vfio_msi_set_block() that releases
the interrupt and its state using vfio_msi_set_vector_signal().

Simplify interrupt cleanup by iterating over allocated interrupts
once.

Signed-off-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
---
drivers/vfio/pci/vfio_pci_intrs.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/vfio/pci/vfio_pci_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c
index bffb0741518b..6a9c6a143cc3 100644
--- a/drivers/vfio/pci/vfio_pci_intrs.c
+++ b/drivers/vfio/pci/vfio_pci_intrs.c
@@ -426,10 +426,9 @@ static void vfio_msi_disable(struct vfio_pci_core_device *vdev, bool msix)
for (i = 0; i < vdev->num_ctx; i++) {
vfio_virqfd_disable(&vdev->ctx[i].unmask);
vfio_virqfd_disable(&vdev->ctx[i].mask);
+ vfio_msi_set_vector_signal(vdev, i, -1, msix);
}

- vfio_msi_set_block(vdev, 0, vdev->num_ctx, NULL, msix);
-
cmd = vfio_pci_memory_lock_and_enable(vdev);
pci_free_irq_vectors(pdev);
vfio_pci_memory_unlock_and_restore(vdev, cmd);
--
2.34.1