On Mon, Apr 29, 2024 at 08:13:56PM +1000, Gavin Shan wrote: > This is suggested by Michael S. Tsirkin according to [1] and the goal > is to apply smp_rmb() inside vhost_get_avail_idx() if needed. With it, > the caller of the function needn't to worry about memory barriers. Since > we're here, other cleanups are also applied. > > [1] https://lore.kernel.org/virtualization/20240327155750-mutt-send-email-mst@xxxxxxxxxx/ Patch 1 makes some sense, gave some comments. Rest I think we should just drop. > PATCH[1] improves vhost_get_avail_idx() so that smp_rmb() is applied if > needed. Besides, the sanity checks on the retrieved available > queue index are also squeezed to vhost_get_avail_idx() > PATCH[2] drops the local variable @last_avail_idx since it's equivalent > to vq->last_avail_idx > PATCH[3] improves vhost_get_avail_head(), similar to what we're doing > for vhost_get_avail_idx(), so that the relevant sanity checks > on the head are squeezed to vhost_get_avail_head() > PATCH[4] Reformat vhost_{get, put}_user() by using tab instead of space > as the terminator for each line > > Gavin Shan (3): > vhost: Drop variable last_avail_idx in vhost_get_vq_desc() > vhost: Improve vhost_get_avail_head() > vhost: Reformat vhost_{get, put}_user() > > Michael S. Tsirkin (1): > vhost: Improve vhost_get_avail_idx() with smp_rmb() > > drivers/vhost/vhost.c | 215 +++++++++++++++++++----------------------- > 1 file changed, 97 insertions(+), 118 deletions(-) > > Changelog > ========= > v2: > * Improve vhost_get_avail_idx() as Michael suggested in [1] > as above (Michael) > * Correct @head's type from 'unsigned int' to 'int' (ltp@xxxxxxxxx) > > -- > 2.44.0