[v3,0/6] qemu-iotests fixes for Kevin's block tree

Message

Stefan Hajnoczi Dec. 21, 2023, 7:24 p.m. UTC

v3:
- Add aio_wait_kick() into nbd_read_eof() to avoid race with nbd_drained_poll()
  [Kevin]

v2:
- Drop useless if (client->quiesing) check [Kevin]
- run qio_channel_read_wake() in export AioContext to avoid race [Kevin]
- Introduce nbd_client_put_nonzero() optimization [Paolo]
- Reach goto label disconnect with client->lock taken [Paolo]
- Add doc comment explaining nbd_co_receive_request() loop in nbd_trip() [Kevin]

Kevin merged several of my outstanding multi-queue block layer patch series and
found that qemu-iotests -qcow2 was broken. This patch series fixes the block branch.

Most of the fixes are easy but the NBD server required deeper debugging and
thread-safety fixes. The NBD server patches can be inserted before "aio: make
aio_context_acquire()/aio_context_release() a no-op" to preserve bisectability.
The other patches are fixups that can be squashed into the original patches.

Stefan Hajnoczi (6):
  fixup block-coroutine-wrapper: use qemu_get_current_aio_context()
  fixup block: remove AioContext locking
  fixup scsi: only access SCSIDevice->requests from one thread
  nbd/server: avoid per-NBDRequest nbd_client_get/put()
  nbd/server: only traverse NBDExport->clients from main loop thread
  nbd/server: introduce NBDClient->lock to protect fields

 hw/scsi/scsi-bus.c            |   3 +-
 migration/block.c             |   7 ++
 nbd/server.c                  | 208 ++++++++++++++++++++++++++--------
 tests/qemu-iotests/051.pc.out |   4 +-
 4 files changed, 173 insertions(+), 49 deletions(-)

Comments

Kevin Wolf Dec. 21, 2023, 9:02 p.m. UTC | #1

Am 21.12.2023 um 20:24 hat Stefan Hajnoczi geschrieben:
> v3:
> - Add aio_wait_kick() into nbd_read_eof() to avoid race with nbd_drained_poll()
>   [Kevin]
> 
> v2:
> - Drop useless if (client->quiesing) check [Kevin]
> - run qio_channel_read_wake() in export AioContext to avoid race [Kevin]
> - Introduce nbd_client_put_nonzero() optimization [Paolo]
> - Reach goto label disconnect with client->lock taken [Paolo]
> - Add doc comment explaining nbd_co_receive_request() loop in nbd_trip() [Kevin]
> 
> Kevin merged several of my outstanding multi-queue block layer patch series and
> found that qemu-iotests -qcow2 was broken. This patch series fixes the block branch.
> 
> Most of the fixes are easy but the NBD server required deeper debugging and
> thread-safety fixes. The NBD server patches can be inserted before "aio: make
> aio_context_acquire()/aio_context_release() a no-op" to preserve bisectability.
> The other patches are fixups that can be squashed into the original patches.

Thanks, applied to the block branch.

Kevin