From ff64e0ba817d79968bffa88d205397abf05cc6e8 Mon Sep 17 00:00:00 2001 From: Avihai Horon Date: Mon, 4 Mar 2024 12:53:39 +0200 Subject: vfio/migration: Add a note about migration rate limiting VFIO migration buffer size is currently limited to 1MB. Therefore, there is no need to check if migration rate exceeded, as in the worst case it will exceed by only 1MB. However, if the buffer size is later changed to a bigger value, vfio_save_iterate() should enforce migration rate (similar to migration RAM code). Add a note about this in vfio_save_iterate() to serve as a reminder. Suggested-by: Peter Xu Signed-off-by: Avihai Horon Reviewed-by: Fabiano Rosas Link: https://lore.kernel.org/r/20240304105339.20713-4-avihaih@nvidia.com Signed-off-by: Peter Xu --- hw/vfio/migration.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'hw/vfio') diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c index 0af783a589..f82dcabc49 100644 --- a/hw/vfio/migration.c +++ b/hw/vfio/migration.c @@ -505,6 +505,12 @@ static bool vfio_is_active_iterate(void *opaque) return vfio_device_state_is_precopy(vbasedev); } +/* + * Note about migration rate limiting: VFIO migration buffer size is currently + * limited to 1MB, so there is no need to check if migration rate exceeded (as + * in the worst case it will exceed by 1MB). However, if the buffer size is + * later changed to a bigger value, migration rate should be enforced here. + */ static int vfio_save_iterate(QEMUFile *f, void *opaque) { VFIODevice *vbasedev = opaque; -- cgit v1.2.3