Re: [PATCH v3 0/5] virtio: drop sizing vqs during init

[Xuan Zhuo]

Series:
Reviewed-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>

There is also a commit, I just submitted, about the problem you pointed
out about using container_of(). Can we submit together?


On Mon, 15 Aug 2022 18:00:21 -0400, "Michael S. Tsirkin" <mst@xxxxxxxxxx> wrote:
> Reporting after I botched up v2 posting. Sorry about the noise.
>
> Supplying size during init does not work for all transports.
> In fact for legacy pci doing that causes a memory
> corruption which was reported on Google Cloud.
>
> We might get away with changing size to size_hint so it's
> safe to ignore and then fixing legacy to ignore the hint.
>
> But the benefit is unclear in any case, so let's revert for now.
> Any new version will have to come with
> - documentation of performance gains
> - performance testing showing existing workflows
>   are not harmed materially. especially ones with
>   bursty traffic
> - report of testing on legacy devices
>
>
> Huge shout out to Andres Freund for the effort spent reproducing and
> debugging!  Thanks to Guenter Roeck for help with testing!
>
>
> changes from v2
> 	drop unrelated patches
> changes from v1
> 	revert the ring size api, it's unused now
>
> Michael S. Tsirkin (5):
>   virtio_net: Revert "virtio_net: set the default max ring size by
>     find_vqs()"
>   virtio: Revert "virtio: add helper virtio_find_vqs_ctx_size()"
>   virtio-mmio: Revert "virtio_mmio: support the arg sizes of find_vqs()"
>   virtio_pci: Revert "virtio_pci: support the arg sizes of find_vqs()"
>   virtio: Revert "virtio: find_vqs() add arg sizes"
>
>  arch/um/drivers/virtio_uml.c             |  2 +-
>  drivers/net/virtio_net.c                 | 42 +++---------------------
>  drivers/platform/mellanox/mlxbf-tmfifo.c |  1 -
>  drivers/remoteproc/remoteproc_virtio.c   |  1 -
>  drivers/s390/virtio/virtio_ccw.c         |  1 -
>  drivers/virtio/virtio_mmio.c             |  9 ++---
>  drivers/virtio/virtio_pci_common.c       | 20 +++++------
>  drivers/virtio/virtio_pci_common.h       |  3 +-
>  drivers/virtio/virtio_pci_legacy.c       |  6 +---
>  drivers/virtio/virtio_pci_modern.c       | 17 +++-------
>  drivers/virtio/virtio_vdpa.c             |  1 -
>  include/linux/virtio_config.h            | 26 +++------------
>  12 files changed, 28 insertions(+), 101 deletions(-)
>
> --
> MST
>