Re: [PATCH 01/12] virtio-scsi: replace AioContext lock with tmf_bh_lock

[Eric Blake]

On Wed, Nov 29, 2023 at 02:55:42PM -0500, Stefan Hajnoczi wrote:
> Protect the Task Management Function BH state with a lock. The TMF BH
> runs in the main loop thread. An IOThread might process a TMF at the
> same time as the TMF BH is running. Therefore tmf_bh_list and tmf_bh
> must be protected by a lock.
> 
> Run TMF request completion in the IOThread using aio_wait_bh_oneshot().
> This avoids more locking to protect the virtqueue and SCSI layer state.

Are we trying to get this into 8.2?

> 
> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
> ---
>  include/hw/virtio/virtio-scsi.h |  3 +-
>  hw/scsi/virtio-scsi.c           | 62 ++++++++++++++++++++++-----------
>  2 files changed, 43 insertions(+), 22 deletions(-)
>

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.
Virtualization:  qemu.org | libguestfs.org