[PATCH v2 0/4] net/virtio: fix memory leak when reinitializing device

[Olivier Matz <olivier.matz@6wind.com>]

When devops->configure() is called, the queues may be reallocated
if the features flag changed, but the previous are not freed. This
patchset fixes this issue.

To really point out the issue, I instrumented rte_malloc,
rte_memzone_reserve, rte_mbuf_alloc to track the allocations and frees.
For reference, the patch is available here:
https://www.droids-corp.org/~zer0/hidden/0001-debug-malloc.patch
Iit conflicts a bit with the patchset, but it is quite easy to solve.

To reproduce the issue:

  cd dpdk
  make config T=x86_64-native-linuxapp-gcc
  sed -i 's,CONFIG_RTE_LIBRTE_VIRTIO_DEBUG_INIT=n,CONFIG_RTE_LIBRTE_VIRTIO_DEBUG_INIT=y,' build/.config
  make -j4
  mkdir -p /mnt/huge
  mount -t hugetlbfs nodev /mnt/huge
  echo 256 > /sys/devices/system/node/node0/hugepages/hugepages-2048kB/nr_hugepages
  modprobe uio_pci_generic
  python usertools/dpdk-devbind.py -b uio_pci_generic 0000:00:02.0
  ./build/app/testpmd -l 0,1 --log-level 8 -- --total-num-mbufs=16384 \
     -i --port-topology=chained --disable-hw-vlan-filter \
     --disable-hw-vlan-strip --enable-rx-cksum --enable-lro \
     --txqflags=0 --no-lsc-interrupt

  # testpmd commands
  port stop 0
  port config all rx-cksum off
  port start 0
  quit

Without the patchset, the debug patch displays a leak of mbufs allocated
from virtio_dev_rx_queue_setup_finish() and a leak of rte_mallocs allocated
from virtio_init_queue().

After the patchset, only one malloc is remaining after the device close,
but this is normal, because this area is freed in dev_uninit().

v1 -> v2:
- move the vq != NULL check from the refactor patch to the memory
  leak fix patch (Yuanhan)
- new patch to fix queue flushing with vector Rx enabled (Tiwei)
- move the backportable fixes at the beginning of the patchset (Yuanhan)
- remove Cc stable on the typo fix (Yuanhan)
  note: I finally kept it in the patchset


Olivier Matz (4):
  net/virtio: fix queue flushing with vector Rx enabled
  net/virtio: fix memory leak when reinitializing device
  net/virtio: rationalize queue flushing
  net/virtio: fix typo in function name

 drivers/net/virtio/virtio_ethdev.c | 71 +++++++++++++++++---------------------
 drivers/net/virtio/virtqueue.c     | 19 ++++++++--
 drivers/net/virtio/virtqueue.h     | 13 ++++++-
 3 files changed, 59 insertions(+), 44 deletions(-)

-- 
2.11.0