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From:   Jason Wang <jasowang@redhat.com>
To:     mst@redhat.com, jasowang@redhat.com
Cc:     davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
        pabeni@redhat.com, virtualization@lists.linux-foundation.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        maxime.coquelin@redhat.com, alvaro.karsz@solid-run.com,
        eperezma@redhat.com
Subject: [PATCH 0/4] virtio-net: don't busy poll for cvq command
Date:   Mon, 26 Dec 2022 15:49:04 +0800
Message-Id: <20221226074908.8154-1-jasowang@redhat.com>
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Hi all:

The code used to busy poll for cvq command which turns out to have
several side effects:

1) infinite poll for buggy devices
2) bad interaction with scheduler

So this series tries to use sleep + timeout instead of busy polling.

Please review.

Thanks

Changes since RFC:

- switch to use BAD_RING in virtio_break_device()
- check virtqueue_is_broken() after being woken up
- use more_used() instead of virtqueue_get_buf() to allow caller to
  get buffers afterwards
- break the virtio-net device when timeout
- get buffer manually since the virtio core check more_used() instead

Jason Wang (4):
  virtio-net: convert rx mode setting to use workqueue
  virtio_ring: switch to use BAD_RING()
  virtio_ring: introduce a per virtqueue waitqueue
  virtio-net: sleep instead of busy waiting for cvq command

 drivers/net/virtio_net.c     | 90 +++++++++++++++++++++++++++++++-----
 drivers/virtio/virtio_ring.c | 37 +++++++++++++--
 include/linux/virtio.h       |  3 ++
 3 files changed, 115 insertions(+), 15 deletions(-)

-- 
2.25.1