For now the switch of vfio dirty page tracking is integrated into the vfio_save_handler, it causes some problems [1].
The object of dirty tracking is guest memory, but the object of the vfio_save_handler is device state. This mixed logic produces unnecessary coupling and conflicts: 1. Coupling: Their saving granule is different (perVM vs perDevice). vfio will enable dirty_page_tracking for each devices, actually once is enough. 2. Conflicts: The ram_save_setup() traverses all memory_listeners to execute their log_start() and log_sync() hooks to get the first round dirty bitmap, which is used by the bulk stage of ram saving. However, it can't get dirty bitmap from vfio, as @savevm_ram_handlers is registered before @vfio_save_handler. Move the switch of vfio dirty_page_tracking into vfio_memory_listener can solve above problems. Besides, Do not require devices in SAVING state for vfio_sync_dirty_bitmap(). [1] https://www.spinics.net/lists/kvm/msg229967.html Reported-by: Zenghui Yu <yuzeng...@huawei.com> Signed-off-by: Keqian Zhu <zhukeqi...@huawei.com> --- hw/vfio/common.c | 53 +++++++++++++++++++++++++++++++++++++-------- hw/vfio/migration.c | 35 ------------------------------ 2 files changed, 44 insertions(+), 44 deletions(-) diff --git a/hw/vfio/common.c b/hw/vfio/common.c index 6ff1daa763..9128cd7ee1 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -311,7 +311,7 @@ bool vfio_mig_active(void) return true; } -static bool vfio_devices_all_saving(VFIOContainer *container) +static bool vfio_devices_all_dirty_tracking(VFIOContainer *container) { VFIOGroup *group; VFIODevice *vbasedev; @@ -329,13 +329,8 @@ static bool vfio_devices_all_saving(VFIOContainer *container) return false; } - if (migration->device_state & VFIO_DEVICE_STATE_SAVING) { - if ((vbasedev->pre_copy_dirty_page_tracking == ON_OFF_AUTO_OFF) - && (migration->device_state & VFIO_DEVICE_STATE_RUNNING)) { - return false; - } - continue; - } else { + if ((vbasedev->pre_copy_dirty_page_tracking == ON_OFF_AUTO_OFF) + && (migration->device_state & VFIO_DEVICE_STATE_RUNNING)) { return false; } } @@ -987,6 +982,44 @@ static void vfio_listener_region_del(MemoryListener *listener, } } +static void vfio_set_dirty_page_tracking(VFIOContainer *container, bool start) +{ + int ret; + struct vfio_iommu_type1_dirty_bitmap dirty = { + .argsz = sizeof(dirty), + }; + + if (start) { + dirty.flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_START; + } else { + dirty.flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP; + } + + ret = ioctl(container->fd, VFIO_IOMMU_DIRTY_PAGES, &dirty); + if (ret) { + error_report("Failed to set dirty tracking flag 0x%x errno: %d", + dirty.flags, errno); + } +} + +static void vfio_listener_log_start(MemoryListener *listener, + MemoryRegionSection *section, + int old, int new) +{ + VFIOContainer *container = container_of(listener, VFIOContainer, listener); + + vfio_set_dirty_page_tracking(container, true); +} + +static void vfio_listener_log_stop(MemoryListener *listener, + MemoryRegionSection *section, + int old, int new) +{ + VFIOContainer *container = container_of(listener, VFIOContainer, listener); + + vfio_set_dirty_page_tracking(container, false); +} + static int vfio_get_dirty_bitmap(VFIOContainer *container, uint64_t iova, uint64_t size, ram_addr_t ram_addr) { @@ -1128,7 +1161,7 @@ static void vfio_listerner_log_sync(MemoryListener *listener, return; } - if (vfio_devices_all_saving(container)) { + if (vfio_devices_all_dirty_tracking(container)) { vfio_sync_dirty_bitmap(container, section); } } @@ -1136,6 +1169,8 @@ static void vfio_listerner_log_sync(MemoryListener *listener, static const MemoryListener vfio_memory_listener = { .region_add = vfio_listener_region_add, .region_del = vfio_listener_region_del, + .log_start = vfio_listener_log_start, + .log_stop = vfio_listener_log_stop, .log_sync = vfio_listerner_log_sync, }; diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c index 00daa50ed8..c0f646823a 100644 --- a/hw/vfio/migration.c +++ b/hw/vfio/migration.c @@ -395,40 +395,10 @@ static int vfio_load_device_config_state(QEMUFile *f, void *opaque) return qemu_file_get_error(f); } -static int vfio_set_dirty_page_tracking(VFIODevice *vbasedev, bool start) -{ - int ret; - VFIOMigration *migration = vbasedev->migration; - VFIOContainer *container = vbasedev->group->container; - struct vfio_iommu_type1_dirty_bitmap dirty = { - .argsz = sizeof(dirty), - }; - - if (start) { - if (migration->device_state & VFIO_DEVICE_STATE_SAVING) { - dirty.flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_START; - } else { - return -EINVAL; - } - } else { - dirty.flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP; - } - - ret = ioctl(container->fd, VFIO_IOMMU_DIRTY_PAGES, &dirty); - if (ret) { - error_report("Failed to set dirty tracking flag 0x%x errno: %d", - dirty.flags, errno); - return -errno; - } - return ret; -} - static void vfio_migration_cleanup(VFIODevice *vbasedev) { VFIOMigration *migration = vbasedev->migration; - vfio_set_dirty_page_tracking(vbasedev, false); - if (migration->region.mmaps) { vfio_region_unmap(&migration->region); } @@ -469,11 +439,6 @@ static int vfio_save_setup(QEMUFile *f, void *opaque) return ret; } - ret = vfio_set_dirty_page_tracking(vbasedev, true); - if (ret) { - return ret; - } - qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); ret = qemu_file_get_error(f); -- 2.19.1