search for: free_page_vq

...gt; + VIRTIO_BALLOON_VQ_STATS, > + VIRTIO_BALLOON_VQ_FREE_PAGE, > + VIRTIO_BALLOON_VQ_MAX > +}; > + > struct virtio_balloon { > struct virtio_device *vdev; > - struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; > + struct virtqueue *inflate_vq, *deflate_vq, *stats_vq, *free_page_vq; > + > + /* Balloon's own wq for cpu-intensive work items */ > + struct workqueue_struct *balloon_wq; > + /* The free page reporting work item submitted to the balloon wq */ > + struct work_struct report_free_page_work; > > /* The balloon servicing is delegated to a fre...

...gt; + VIRTIO_BALLOON_VQ_STATS, > + VIRTIO_BALLOON_VQ_FREE_PAGE, > + VIRTIO_BALLOON_VQ_MAX > +}; > + > struct virtio_balloon { > struct virtio_device *vdev; > - struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; > + struct virtqueue *inflate_vq, *deflate_vq, *stats_vq, *free_page_vq; > + > + /* Balloon's own wq for cpu-intensive work items */ > + struct workqueue_struct *balloon_wq; > + /* The free page reporting work item submitted to the balloon wq */ > + struct work_struct report_free_page_work; > > /* The balloon servicing is delegated to a fre...

...a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -54,11 +54,12 @@ static struct vfsmount *balloon_mnt; struct virtio_balloon { struct virtio_device *vdev; - struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; + struct virtqueue *inflate_vq, *deflate_vq, *stats_vq, *free_page_vq; /* The balloon servicing is delegated to a freezable workqueue. */ struct work_struct update_balloon_stats_work; struct work_struct update_balloon_size_work; + struct work_struct report_free_page_work; /* Prevent updating balloon when it is being canceled. */ spinlock_t stop_update_l...

...o queues > (indexes 0 and 1) are available as part of the baseline device, but the > rest of the queues are tied to feature bits. > > Section 5.5.2, "Virtqueues", gives a list that appears to be a mapping from > queue index to queue name/function, defining queue index 3 as free_page_vq > and index 4 as reporting_vq, and declaring that "free_page_vq only exists > if VIRTIO_BALLOON_F_FREE_PAGE_HINT is set" and "reporting_vq only exists if > VIRTIO_BALLOON_F_PAGE_REPORTING is set." This wording is a bit vague, but I > assume "is set" means &...

...ON_VQ_INFLATE, + VIRTIO_BALLOON_VQ_DEFLATE, + VIRTIO_BALLOON_VQ_STATS, + VIRTIO_BALLOON_VQ_FREE_PAGE, + VIRTIO_BALLOON_VQ_MAX +}; + struct virtio_balloon { struct virtio_device *vdev; - struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; + struct virtqueue *inflate_vq, *deflate_vq, *stats_vq, *free_page_vq; + + /* Balloon's own wq for cpu-intensive work items */ + struct workqueue_struct *balloon_wq; + /* The free page reporting work item submitted to the balloon wq */ + struct work_struct report_free_page_work; /* The balloon servicing is delegated to a freezable workqueue. */ struct work_...

...device [1]. The first two queues (indexes 0 and 1) are available as part of the baseline device, but the rest of the queues are tied to feature bits. Section 5.5.2, "Virtqueues", gives a list that appears to be a mapping from queue index to queue name/function, defining queue index 3 as free_page_vq and index 4 as reporting_vq, and declaring that "free_page_vq only exists if VIRTIO_BALLOON_F_FREE_PAGE_HINT is set" and "reporting_vq only exists if VIRTIO_BALLOON_F_PAGE_REPORTING is set." This wording is a bit vague, but I assume "is set" means "is negotiated&q...

...rtio/virtio_balloon.c > @@ -54,11 +54,12 @@ static struct vfsmount *balloon_mnt; > > struct virtio_balloon { > struct virtio_device *vdev; > - struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; > + struct virtqueue *inflate_vq, *deflate_vq, *stats_vq, *free_page_vq; > > /* The balloon servicing is delegated to a freezable workqueue. */ > struct work_struct update_balloon_stats_work; > struct work_struct update_balloon_size_work; > + struct work_struct report_free_page_work; > > /* Prevent upd...

...rtio/virtio_balloon.c > @@ -54,11 +54,12 @@ static struct vfsmount *balloon_mnt; > > struct virtio_balloon { > struct virtio_device *vdev; > - struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; > + struct virtqueue *inflate_vq, *deflate_vq, *stats_vq, *free_page_vq; > > /* The balloon servicing is delegated to a freezable workqueue. */ > struct work_struct update_balloon_stats_work; > struct work_struct update_balloon_size_work; > + struct work_struct report_free_page_work; > > /* Prevent upd...

...ON_VQ_INFLATE, + VIRTIO_BALLOON_VQ_DEFLATE, + VIRTIO_BALLOON_VQ_STATS, + VIRTIO_BALLOON_VQ_FREE_PAGE, + VIRTIO_BALLOON_VQ_MAX +}; + struct virtio_balloon { struct virtio_device *vdev; - struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; + struct virtqueue *inflate_vq, *deflate_vq, *stats_vq, *free_page_vq; + + /* Balloon's own wq for cpu-intensive work items */ + struct workqueue_struct *balloon_wq; + /* The free page reporting work item submitted to the balloon wq */ + struct work_struct report_free_page_work; /* The balloon servicing is delegated to a freezable workqueue. */ struct work_...

...gt; + VIRTIO_BALLOON_VQ_STATS, > + VIRTIO_BALLOON_VQ_FREE_PAGE, > + VIRTIO_BALLOON_VQ_MAX > +}; > + > struct virtio_balloon { > struct virtio_device *vdev; > - struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; > + struct virtqueue *inflate_vq, *deflate_vq, *stats_vq, *free_page_vq; > + > + /* Balloon's own wq for cpu-intensive work items */ > + struct workqueue_struct *balloon_wq; > + /* The free page reporting work item submitted to the balloon wq */ > + struct work_struct report_free_page_work; > > /* The balloon servicing is delegated to a fre...

...ON_VQ_INFLATE, + VIRTIO_BALLOON_VQ_DEFLATE, + VIRTIO_BALLOON_VQ_STATS, + VIRTIO_BALLOON_VQ_FREE_PAGE, + VIRTIO_BALLOON_VQ_MAX +}; + struct virtio_balloon { struct virtio_device *vdev; - struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; + struct virtqueue *inflate_vq, *deflate_vq, *stats_vq, *free_page_vq; + + /* Balloon's own wq for cpu-intensive work items */ + struct workqueue_struct *balloon_wq; + /* The free page reporting work item submitted to the balloon wq */ + struct work_struct report_free_page_work; /* The balloon servicing is delegated to a freezable workqueue. */ struct work_...

...ON_VQ_INFLATE, + VIRTIO_BALLOON_VQ_DEFLATE, + VIRTIO_BALLOON_VQ_STATS, + VIRTIO_BALLOON_VQ_FREE_PAGE, + VIRTIO_BALLOON_VQ_MAX +}; + struct virtio_balloon { struct virtio_device *vdev; - struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; + struct virtqueue *inflate_vq, *deflate_vq, *stats_vq, *free_page_vq; + + /* Balloon's own wq for cpu-intensive work items */ + struct workqueue_struct *balloon_wq; + /* The free page reporting work item submitted to the balloon wq */ + struct work_struct report_free_page_work; /* The balloon servicing is delegated to a freezable workqueue. */ struct work_...

Negotiation of the VIRTIO_BALLOON_F_FREE_PAGE_VQ feature indicates the support of reporting hints of guest free pages to host via virtio-balloon. Host requests the guest to report free pages by sending a new cmd id to the guest via the free_page_report_cmd_id configuration register. When the guest starts to report, the first element added to th...

...ther direction which would be easier - using two 32-bit device > specific configuration registers, > Host2Guest and Guest2Host command registers, to replace the ctrlq for > command exchange: > > The flow can be as follows: > > 1) Before Host sending a StartCMD, it flushes the free_page_vq in case any > old free page hint is left there; > 2) Host writes StartCMD to the Host2Guest register, and notifies the guest; > > 3) Upon receiving a configuration notification, Guest reads the Host2Guest > register, and detaches all the used buffers from free_page_vq; > (then f...

...ther direction which would be easier - using two 32-bit device > specific configuration registers, > Host2Guest and Guest2Host command registers, to replace the ctrlq for > command exchange: > > The flow can be as follows: > > 1) Before Host sending a StartCMD, it flushes the free_page_vq in case any > old free page hint is left there; > 2) Host writes StartCMD to the Host2Guest register, and notifies the guest; > > 3) Upon receiving a configuration notification, Guest reads the Host2Guest > register, and detaches all the used buffers from free_page_vq; > (then f...

This patch series is separated from the previous "Virtio-balloon Enhancement" series. The new feature, VIRTIO_BALLOON_F_FREE_PAGE_VQ, 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 memory from the source machine to the destinatio...

On Wed, Jan 17, 2018 at 01:10:11PM +0800, Wei Wang wrote: > Negotiation of the VIRTIO_BALLOON_F_FREE_PAGE_VQ feature indicates the > support of reporting hints of guest free pages to host via virtio-balloon. > > Host requests the guest to report free pages by sending a new cmd > id to the guest via the free_page_report_cmd_id configuration register. > > When the guest starts to report,...

On Wed, Jan 17, 2018 at 01:10:11PM +0800, Wei Wang wrote: > Negotiation of the VIRTIO_BALLOON_F_FREE_PAGE_VQ feature indicates the > support of reporting hints of guest free pages to host via virtio-balloon. > > Host requests the guest to report free pages by sending a new cmd > id to the guest via the free_page_report_cmd_id configuration register. > > When the guest starts to report,...

...I still think it's a good idea but go ahead and propose something else that works. > > > > Thanks for the suggestion. Probably I haven't fully understood it. Please see the example > below: > > 1) host-to-guest ctrl_vq: > StartCMD, ID=1 > > 2) guest-to-host free_page_vq: > free_page, ID=1 > free_page, ID=1 > free_page, ID=1 > free_page, ID=1 > > 3) host-to-guest ctrl_vq: > StopCMD, ID=1 > > 4) initiate the 2nd try of live migration via host-to-guest ctrl_vq: > StartCMD, ID=2 > > 5) the guest-to-host free_page_vq might look li...

...I still think it's a good idea but go ahead and propose something else that works. > > > > Thanks for the suggestion. Probably I haven't fully understood it. Please see the example > below: > > 1) host-to-guest ctrl_vq: > StartCMD, ID=1 > > 2) guest-to-host free_page_vq: > free_page, ID=1 > free_page, ID=1 > free_page, ID=1 > free_page, ID=1 > > 3) host-to-guest ctrl_vq: > StopCMD, ID=1 > > 4) initiate the 2nd try of live migration via host-to-guest ctrl_vq: > StartCMD, ID=2 > > 5) the guest-to-host free_page_vq might look li...