From 285e71ea6f3583a85e27cb2b9a7d8c35d4c0d558 Mon Sep 17 00:00:00 2001 From: Wanlong Gao Date: Mon, 8 Apr 2013 23:05:49 +0930 Subject: [PATCH] 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 Signed-off-by: Wanlong Gao Reviewed-by: Asias He Signed-off-by: Rusty Russell --- drivers/scsi/virtio_scsi.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) 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 @@ struct virtio_scsi { /* 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 @@ static void virtscsi_set_affinity(struct virtio_scsi *vscsi, bool affinity) 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 @@ static int virtscsi_probe(struct virtio_device *vdev) 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 @@ static void virtscsi_remove(struct virtio_device *vdev) scsi_remove_host(shost); + unregister_hotcpu_notifier(&vscsi->nb); + virtscsi_remove_vqs(vdev); scsi_host_put(shost); } -- 2.7.4