Messages in this thread | | | Date | Mon, 8 Apr 2024 14:15:24 +1000 | Subject | Re: [PATCH v3 3/3] vhost: Improve vhost_get_avail_idx() with smp_rmb() | From | Gavin Shan <> |
| |
Hi Michael,
On 3/30/24 19:02, Gavin Shan wrote: > On 3/28/24 19:31, Michael S. Tsirkin wrote: >> On Thu, Mar 28, 2024 at 10:21:49AM +1000, Gavin Shan wrote: >>> All the callers of vhost_get_avail_idx() are concerned to the memory >>> barrier, imposed by smp_rmb() to ensure the order of the available >>> ring entry read and avail_idx read. >>> >>> Improve vhost_get_avail_idx() so that smp_rmb() is executed when >>> the avail_idx is advanced. With it, the callers needn't to worry >>> about the memory barrier. >>> >>> Suggested-by: Michael S. Tsirkin <mst@redhat.com> >>> Signed-off-by: Gavin Shan <gshan@redhat.com> >> >> Previous patches are ok. This one I feel needs more work - >> first more code such as sanity checking should go into >> this function, second there's actually a difference >> between comparing to last_avail_idx and just comparing >> to the previous value of avail_idx. >> I will pick patches 1-2 and post a cleanup on top so you can >> take a look, ok? >> > > Thanks, Michael. It's fine to me. >
A kindly ping.
If it's ok to you, could you please merge PATCH[1-2]? Our downstream 9.4 need the fixes, especially for NVidia's grace-hopper and grace-grace platforms.
For PATCH[3], I also can help with the improvement if you don't have time for it. Please let me know.
Thanks, Gavin
| |