[PATCH v7 06/10] virtio: blk/scsi: use block layer helpers to constrain queue affinity

[Daniel Wagner]

Ensure that IRQ affinity setup also respects the queue-to-CPU mapping
constraints provided by the block layer. This allows the virtio drivers
to avoid assigning interrupts to CPUs that the block layer has excluded
(e.g., isolated CPUs).

Signed-off-by: Daniel Wagner <w...@kernel.org>
---
 drivers/block/virtio_blk.c | 4 +++-
 drivers/scsi/virtio_scsi.c | 5 ++++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 
e649fa67bac16b4f0c6e8e8f0e6bec111897c355..41b06540c7fb22fd1d2708338c514947c4bdeefe
 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -963,7 +963,9 @@ static int init_vq(struct virtio_blk *vblk)
        unsigned short num_vqs;
        unsigned short num_poll_vqs;
        struct virtio_device *vdev = vblk->vdev;
-       struct irq_affinity desc = { 0, };
+       struct irq_affinity desc = {
+               .mask = blk_mq_possible_queue_affinity(),
+       };
 
        err = virtio_cread_feature(vdev, VIRTIO_BLK_F_MQ,
                                   struct virtio_blk_config, num_queues,
diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index 
96a69edddbe5555574fc8fed1ba7c82a99df4472..67dfb265bf9e54adc68978ac8d93187e6629c330
 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -842,7 +842,10 @@ static int virtscsi_init(struct virtio_device *vdev,
        u32 num_vqs, num_poll_vqs, num_req_vqs;
        struct virtqueue_info *vqs_info;
        struct virtqueue **vqs;
-       struct irq_affinity desc = { .pre_vectors = 2 };
+       struct irq_affinity desc = {
+               .pre_vectors = 2,
+               .mask = blk_mq_possible_queue_affinity(),
+       };
 
        num_req_vqs = vscsi->num_queues;
        num_vqs = num_req_vqs + VIRTIO_SCSI_VQ_BASE;

-- 
2.50.0