diff options
Diffstat (limited to 'drivers/virtio/virtio_balloon.c')
| -rw-r--r-- | drivers/virtio/virtio_balloon.c | 85 |
1 files changed, 55 insertions, 30 deletions
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 1f5b3dd31fcf..c0a63638f95e 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -121,11 +121,14 @@ struct virtio_balloon { struct page_reporting_dev_info pr_dev_info; /* State for keeping the wakeup_source active while adjusting the balloon */ - spinlock_t adjustment_lock; - bool adjustment_signal_pending; - bool adjustment_in_progress; + spinlock_t wakeup_lock; + bool processing_wakeup_event; + u32 wakeup_signal_mask; }; +#define VIRTIO_BALLOON_WAKEUP_SIGNAL_ADJUST (1 << 0) +#define VIRTIO_BALLOON_WAKEUP_SIGNAL_STATS (1 << 1) + static const struct virtio_device_id id_table[] = { { VIRTIO_ID_BALLOON, VIRTIO_DEV_ANY_ID }, { 0 }, @@ -140,6 +143,36 @@ static u32 page_to_balloon_pfn(struct page *page) return pfn * VIRTIO_BALLOON_PAGES_PER_PAGE; } +static void start_wakeup_event(struct virtio_balloon *vb, u32 mask) +{ + unsigned long flags; + + spin_lock_irqsave(&vb->wakeup_lock, flags); + vb->wakeup_signal_mask |= mask; + if (!vb->processing_wakeup_event) { + vb->processing_wakeup_event = true; + pm_stay_awake(&vb->vdev->dev); + } + spin_unlock_irqrestore(&vb->wakeup_lock, flags); +} + +static void process_wakeup_event(struct virtio_balloon *vb, u32 mask) +{ + spin_lock_irq(&vb->wakeup_lock); + vb->wakeup_signal_mask &= ~mask; + spin_unlock_irq(&vb->wakeup_lock); +} + +static void finish_wakeup_event(struct virtio_balloon *vb) +{ + spin_lock_irq(&vb->wakeup_lock); + if (!vb->wakeup_signal_mask && vb->processing_wakeup_event) { + vb->processing_wakeup_event = false; + pm_relax(&vb->vdev->dev); + } + spin_unlock_irq(&vb->wakeup_lock); +} + static void balloon_ack(struct virtqueue *vq) { struct virtio_balloon *vb = vq->vdev->priv; @@ -370,8 +403,10 @@ static void stats_request(struct virtqueue *vq) struct virtio_balloon *vb = vq->vdev->priv; spin_lock(&vb->stop_update_lock); - if (!vb->stop_update) + if (!vb->stop_update) { + start_wakeup_event(vb, VIRTIO_BALLOON_WAKEUP_SIGNAL_STATS); queue_work(system_freezable_wq, &vb->update_balloon_stats_work); + } spin_unlock(&vb->stop_update_lock); } @@ -444,29 +479,10 @@ static void virtio_balloon_queue_free_page_work(struct virtio_balloon *vb) static void start_update_balloon_size(struct virtio_balloon *vb) { - unsigned long flags; - - spin_lock_irqsave(&vb->adjustment_lock, flags); - vb->adjustment_signal_pending = true; - if (!vb->adjustment_in_progress) { - vb->adjustment_in_progress = true; - pm_stay_awake(vb->vdev->dev.parent); - } - spin_unlock_irqrestore(&vb->adjustment_lock, flags); - + start_wakeup_event(vb, VIRTIO_BALLOON_WAKEUP_SIGNAL_ADJUST); queue_work(system_freezable_wq, &vb->update_balloon_size_work); } -static void end_update_balloon_size(struct virtio_balloon *vb) -{ - spin_lock_irq(&vb->adjustment_lock); - if (!vb->adjustment_signal_pending && vb->adjustment_in_progress) { - vb->adjustment_in_progress = false; - pm_relax(vb->vdev->dev.parent); - } - spin_unlock_irq(&vb->adjustment_lock); -} - static void virtballoon_changed(struct virtio_device *vdev) { struct virtio_balloon *vb = vdev->priv; @@ -495,7 +511,10 @@ static void update_balloon_stats_func(struct work_struct *work) vb = container_of(work, struct virtio_balloon, update_balloon_stats_work); + + process_wakeup_event(vb, VIRTIO_BALLOON_WAKEUP_SIGNAL_STATS); stats_handle_request(vb); + finish_wakeup_event(vb); } static void update_balloon_size_func(struct work_struct *work) @@ -506,9 +525,7 @@ static void update_balloon_size_func(struct work_struct *work) vb = container_of(work, struct virtio_balloon, update_balloon_size_work); - spin_lock_irq(&vb->adjustment_lock); - vb->adjustment_signal_pending = false; - spin_unlock_irq(&vb->adjustment_lock); + process_wakeup_event(vb, VIRTIO_BALLOON_WAKEUP_SIGNAL_ADJUST); diff = towards_target(vb); @@ -523,7 +540,7 @@ static void update_balloon_size_func(struct work_struct *work) if (diff) queue_work(system_freezable_wq, work); else - end_update_balloon_size(vb); + finish_wakeup_event(vb); } static int init_vqs(struct virtio_balloon *vb) @@ -1027,7 +1044,16 @@ static int virtballoon_probe(struct virtio_device *vdev) goto out_unregister_oom; } - spin_lock_init(&vb->adjustment_lock); + spin_lock_init(&vb->wakeup_lock); + + /* + * The virtio balloon itself can't wake up the device, but it is + * responsible for processing wakeup events passed up from the transport + * layer. Wakeup sources don't support nesting/chaining calls, so we use + * our own wakeup source to ensure wakeup events are properly handled + * without trampling on the transport layer's wakeup source. + */ + device_set_wakeup_capable(&vb->vdev->dev, true); virtio_device_ready(vdev); @@ -1155,7 +1181,6 @@ static struct virtio_driver virtio_balloon_driver = { .feature_table = features, .feature_table_size = ARRAY_SIZE(features), .driver.name = KBUILD_MODNAME, - .driver.owner = THIS_MODULE, .id_table = id_table, .validate = virtballoon_validate, .probe = virtballoon_probe, |