virtio-scsi: reset virtqueue affinity when doing cpu hotplug
Add hot cpu notifier to reset the request virtqueue affinity
when doing cpu hotplug.
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Reviewed-by: Asias He <asias@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index 8dcdef0..2168258 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -110,6 +110,9 @@
/* If the affinity hint is set for virtqueues */
bool affinity_hint_set;
+ /* CPU hotplug notifier */
+ struct notifier_block nb;
+
struct virtio_scsi_vq ctrl_vq;
struct virtio_scsi_vq event_vq;
struct virtio_scsi_vq req_vqs[];
@@ -762,6 +765,23 @@
put_online_cpus();
}
+static int virtscsi_cpu_callback(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ struct virtio_scsi *vscsi = container_of(nfb, struct virtio_scsi, nb);
+ switch(action) {
+ case CPU_ONLINE:
+ case CPU_ONLINE_FROZEN:
+ case CPU_DEAD:
+ case CPU_DEAD_FROZEN:
+ __virtscsi_set_affinity(vscsi, true);
+ break;
+ default:
+ break;
+ }
+ return NOTIFY_OK;
+}
+
static void virtscsi_init_vq(struct virtio_scsi_vq *virtscsi_vq,
struct virtqueue *vq)
{
@@ -884,6 +904,13 @@
if (err)
goto virtscsi_init_failed;
+ vscsi->nb.notifier_call = &virtscsi_cpu_callback;
+ err = register_hotcpu_notifier(&vscsi->nb);
+ if (err) {
+ pr_err("registering cpu notifier failed\n");
+ goto scsi_add_host_failed;
+ }
+
cmd_per_lun = virtscsi_config_get(vdev, cmd_per_lun) ?: 1;
shost->cmd_per_lun = min_t(u32, cmd_per_lun, shost->can_queue);
shost->max_sectors = virtscsi_config_get(vdev, max_sectors) ?: 0xFFFF;
@@ -921,6 +948,8 @@
scsi_remove_host(shost);
+ unregister_hotcpu_notifier(&vscsi->nb);
+
virtscsi_remove_vqs(vdev);
scsi_host_put(shost);
}