search for: out_free_vb

..._mnt' undeclared (first use in this function) kern_unmount(balloon_mnt); ^ drivers/virtio/virtio_balloon.c:578:15: note: each undeclared identifier is reported only once for each function it appears in >> drivers/virtio/virtio_balloon.c:579:1: warning: label 'out_free_vb' defined but not used [-Wunused-label] out_free_vb: ^ vim +/balloon_mnt +578 drivers/virtio/virtio_balloon.c 572 573 out_oom_notify: 574 vdev->config->del_vqs(vdev); 575 out_unmount: 576 if (vb->vb_dev_info.inode) 577 iput(vb->vb_dev_info.inode); &g...

..._mnt' undeclared (first use in this function) kern_unmount(balloon_mnt); ^ drivers/virtio/virtio_balloon.c:578:15: note: each undeclared identifier is reported only once for each function it appears in >> drivers/virtio/virtio_balloon.c:579:1: warning: label 'out_free_vb' defined but not used [-Wunused-label] out_free_vb: ^ vim +/balloon_mnt +578 drivers/virtio/virtio_balloon.c 572 573 out_oom_notify: 574 vdev->config->del_vqs(vdev); 575 out_unmount: 576 if (vb->vb_dev_info.inode) 577 iput(vb->vb_dev_info.inode); &g...

...a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -959,9 +959,9 @@ static int virtballoon_probe(struct virtio_device *vdev) iput(vb->vb_dev_info.inode); out_kern_unmount: kern_unmount(balloon_mnt); -#endif out_del_vqs: vdev->config->del_vqs(vdev); +#endif out_free_vb: kfree(vb); out: -- 2.21.0

...a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -959,9 +959,9 @@ static int virtballoon_probe(struct virtio_device *vdev) iput(vb->vb_dev_info.inode); out_kern_unmount: kern_unmount(balloon_mnt); -#endif out_del_vqs: vdev->config->del_vqs(vdev); +#endif out_free_vb: kfree(vb); out: -- 2.21.0

...a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -959,8 +959,8 @@ static int virtballoon_probe(struct virtio_device *vdev) iput(vb->vb_dev_info.inode); out_kern_unmount: kern_unmount(balloon_mnt); -#endif out_del_vqs: +#endif vdev->config->del_vqs(vdev); out_free_vb: kfree(vb); -- 2.25.0

...a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -959,8 +959,8 @@ static int virtballoon_probe(struct virtio_device *vdev) iput(vb->vb_dev_info.inode); out_kern_unmount: kern_unmount(balloon_mnt); -#endif out_del_vqs: +#endif vdev->config->del_vqs(vdev); out_free_vb: kfree(vb); -- 2.25.0

...tatic struct file_system_type balloon_fs = { static int virtballoon_probe(struct virtio_device *vdev) { struct virtio_balloon *vb; + __u32 poison_val; int err; if (!vdev->config->get) { @@ -566,18 +715,39 @@ static int virtballoon_probe(struct virtio_device *vdev) if (err) goto out_free_vb; + if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) { + /* + * There is always one entry reserved for cmd id, so the ring + * size needs to be at least two to report free page hints. + */ + if (virtqueue_get_vring_size(vb->free_page_vq) < 2) + goto out_free_vb; + vb...

...tatic struct file_system_type balloon_fs = { static int virtballoon_probe(struct virtio_device *vdev) { struct virtio_balloon *vb; + __u32 poison_val; int err; if (!vdev->config->get) { @@ -566,18 +715,39 @@ static int virtballoon_probe(struct virtio_device *vdev) if (err) goto out_free_vb; + if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) { + /* + * There is always one entry reserved for cmd id, so the ring + * size needs to be at least two to report free page hints. + */ + if (virtqueue_get_vring_size(vb->free_page_vq) < 2) + goto out_free_vb; + vb...

...tatic struct file_system_type balloon_fs = { static int virtballoon_probe(struct virtio_device *vdev) { struct virtio_balloon *vb; + __u32 poison_val; int err; if (!vdev->config->get) { @@ -566,18 +711,39 @@ static int virtballoon_probe(struct virtio_device *vdev) if (err) goto out_free_vb; + if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) { + /* + * There is always one entry reserved for cmd id, so the ring + * size needs to be at least two to report free page hint. + */ + if (virtqueue_get_vring_size(vb->free_page_vq) < 2) + goto out_free_vb; + vb-...

...d_pages = leak_balloon(vb, oom_pages); + update_balloon_size(vb); + *freed += num_freed_pages; + + return NOTIFY_OK; +} + static int balloon(void *_vballoon) { struct virtio_balloon *vb = _vballoon; @@ -446,6 +488,12 @@ static int virtballoon_probe(struct virtio_device *vdev) if (err) goto out_free_vb; + vb->nb.notifier_call = virtballoon_oom_notify; + vb->nb.priority = VIRTBALLOON_OOM_NOTIFY_PRIORITY; + err = register_oom_notifier(&vb->nb); + if (err < 0) + goto out_oom_notify; + vb->thread = kthread_run(balloon, vb, "vballoon"); if (IS_ERR(vb->thread)) {...

...d_pages = leak_balloon(vb, oom_pages); + update_balloon_size(vb); + *freed += num_freed_pages; + + return NOTIFY_OK; +} + static int balloon(void *_vballoon) { struct virtio_balloon *vb = _vballoon; @@ -446,6 +488,12 @@ static int virtballoon_probe(struct virtio_device *vdev) if (err) goto out_free_vb; + vb->nb.notifier_call = virtballoon_oom_notify; + vb->nb.priority = VIRTBALLOON_OOM_NOTIFY_PRIORITY; + err = register_oom_notifier(&vb->nb); + if (err < 0) + goto out_oom_notify; + vb->thread = kthread_run(balloon, vb, "vballoon"); if (IS_ERR(vb->thread)) {...

...vdev->dev, "%s: free page vq failure, ret=%d\n", + __func__, ret); +} + #ifdef CONFIG_BALLOON_COMPACTION /* * virtballoon_migratepage - perform the balloon page migration on behalf of @@ -570,18 +728,36 @@ static int virtballoon_probe(struct virtio_device *vdev) if (err) goto out_free_vb; + if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) { + /* + * There is always one entry reserved for cmd id, so the ring + * size needs to be at least two to report free page hints. + */ + if (virtqueue_get_vring_size(vb->free_page_vq) < 2) + goto out_free_vb; + vb...

...vdev->dev, "%s: free page vq failure, ret=%d\n", + __func__, ret); +} + #ifdef CONFIG_BALLOON_COMPACTION /* * virtballoon_migratepage - perform the balloon page migration on behalf of @@ -570,18 +743,36 @@ static int virtballoon_probe(struct virtio_device *vdev) if (err) goto out_free_vb; + if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) { + /* + * There is always one entry reserved for cmd id, so the ring + * size needs to be at least two to report free page hints. + */ + if (virtqueue_get_vring_size(vb->free_page_vq) < 2) + goto out_free_vb; + vb...

...static int virtballoon_probe(struct virtio_device *vdev) > { > struct virtio_balloon *vb; > + __u32 poison_val; > int err; > > if (!vdev->config->get) { > @@ -566,18 +715,39 @@ static int virtballoon_probe(struct virtio_device *vdev) > if (err) > goto out_free_vb; > > + if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) { > + /* > + * There is always one entry reserved for cmd id, so the ring > + * size needs to be at least two to report free page hints. > + */ > + if (virtqueue_get_vring_size(vb->free_page_vq)...

Excessive virtio_balloon inflation can cause invocation of OOM-killer, when Linux is under severe memory pressure. Various mechanisms are responsible for correct virtio_balloon memory management. Nevertheless it is often the case that these control tools does not have enough time to react on fast changing memory load. As a result OS runs out of memory and invokes OOM-killer. The balancing of

Excessive virtio_balloon inflation can cause invocation of OOM-killer, when Linux is under severe memory pressure. Various mechanisms are responsible for correct virtio_balloon memory management. Nevertheless it is often the case that these control tools does not have enough time to react on fast changing memory load. As a result OS runs out of memory and invokes OOM-killer. The balancing of

...t virtio_device *vdev) @@ -516,12 +540,25 @@ static int virtballoon_probe(struct virtio_device *vdev) balloon_devinfo_init(&vb->vb_dev_info); #ifdef CONFIG_BALLOON_COMPACTION + balloon_mnt = kern_mount(&balloon_fs); + if (IS_ERR(balloon_mnt)) { + err = PTR_ERR(balloon_mnt); + goto out_free_vb; + } + vb->vb_dev_info.migratepage = virtballoon_migratepage; + vb->vb_dev_info.inode = alloc_anon_inode(balloon_mnt->mnt_sb); + if (IS_ERR(vb->vb_dev_info.inode)) { + err = PTR_ERR(vb->vb_dev_info.inode); + vb->vb_dev_info.inode = NULL; + goto out_unmount; + } + vb->vb_de...

This patch series is separated from the previous "Virtio-balloon Enhancement" series. The new feature, VIRTIO_BALLOON_F_FREE_PAGE_HINT, implemented by this series enables the virtio-balloon driver to report hints of guest free pages to the host. It can be used to accelerate live migration of VMs. Here is an introduction of this usage: Live migration needs to transfer the VM's

...t;num_pages = 0; mutex_init(&vb->balloon_lock); - init_waitqueue_head(&vb->config_change); init_waitqueue_head(&vb->acked); vb->vdev = vdev; vb->need_stats_update = 0; @@ -443,16 +435,8 @@ static int virtballoon_probe(struct virtio_device *vdev) if (err) goto out_free_vb; - vb->thread = kthread_run(balloon, vb, "vballoon"); - if (IS_ERR(vb->thread)) { - err = PTR_ERR(vb->thread); - goto out_del_vqs; - } - return 0; -out_del_vqs: - vdev->config->del_vqs(vdev); out_free_vb: kfree(vb); out: @@ -476,7 +460,6 @@ static void virtballo...

...t;num_pages = 0; mutex_init(&vb->balloon_lock); - init_waitqueue_head(&vb->config_change); init_waitqueue_head(&vb->acked); vb->vdev = vdev; vb->need_stats_update = 0; @@ -443,16 +435,8 @@ static int virtballoon_probe(struct virtio_device *vdev) if (err) goto out_free_vb; - vb->thread = kthread_run(balloon, vb, "vballoon"); - if (IS_ERR(vb->thread)) { - err = PTR_ERR(vb->thread); - goto out_del_vqs; - } - return 0; -out_del_vqs: - vdev->config->del_vqs(vdev); out_free_vb: kfree(vb); out: @@ -476,7 +460,6 @@ static void virtballo...