search for: virtio_balloon_free_page_don

...hypervisor sets FREE_PAGE_REPORT_S_DONE. > > Can't find that one anywhere. what did I miss? Sorry, the QEMU implementation is confusing. FREE_PAGE_REPORT_S_DONE is translated to VIRTIO_BALLOON_CMD_ID_DONE QEMU: hw/virtio/virtio-balloon.c:virtio_balloon_free_page_report_notify() -> virtio_balloon_free_page_done(dev) -> s->free_page_report_status = FREE_PAGE_REPORT_S_DONE; virtio_notify_config(vdev); When the guest reads the config hw/virtio/virtio-balloon.c:virtio_balloon_get_config() -> if (dev->free_page_report_status == FREE_PAGE_REPORT_S_DONE) -> config.free_page_report_cmd_id = .....

...MD_ID_DONE Well VIRTIO_BALLOON_CMD_ID_DONE just means "don't give me any more hints, I finished migration". Guest will stop hinting even without that once it scans all free memory. > QEMU: > > hw/virtio/virtio-balloon.c:virtio_balloon_free_page_report_notify() > -> virtio_balloon_free_page_done(dev) > -> s->free_page_report_status = FREE_PAGE_REPORT_S_DONE; > virtio_notify_config(vdev); > > When the guest reads the config > hw/virtio/virtio-balloon.c:virtio_balloon_get_config() > -> if (dev->free_page_report_status == FREE_PAGE_REPORT_S_DONE) > ->...

> What do you call "hinting ends" though? The fact we put > a page in the VQ is not a guarantee that it's been consumed > by the hypervisor. > I'd say hinting ends once the hypervisor sets FREE_PAGE_REPORT_S_DONE. > > I think a strict definition is this: > - hint includes a command ID > - hint implies "page was unused at some point after guest