Hi all!
Here is a new migration parameter backend-transfer, which allows to
enable local migration of TAP virtio-net backend, including its
properties and open fds.
With this new option, management software doesn't need to
initialize new TAP and do a switch to it. Nothing should be
done around virtio-net in local migration: it just migrates
and continues to use same TAP device. So we avoid extra logic
in management software, extra allocations in kernel (for new TAP),
and corresponding extra delay in migration downtime.
v6:
- rebase on master (to solve conflict with merged
"io: deal with blocking/non-blocking fds")
- use name "backend-transfer" for the whole feature consistently
though the whole series. (live-backend is good, but actually,
we are already in "live-migration", so every its feature may
have "live-" prefix, and it seems redundant)
03-04: new, making changes in 05 correct
08-09: split "net/tap: rework tap_set_sndbuf()" into two commits
15: fix windows compilation
16: move has_ = true, to _params_init
18: use shorter name
and some other cosmetic changes.
Vladimir Sementsov-Ogievskiy (19):
net/tap: net_init_tap_one(): drop extra error propagation
net/tap: net_init_tap_one(): move parameter checking earlier
net/tap: rework net_tap_init()
net/tap: pass NULL to net_init_tap_one() in cases when scripts are
NULL
net/tap: rework scripts handling
net/tap: setup exit notifier only when needed
net/tap: split net_tap_fd_init()
net/tap: tap_set_sndbuf(): add return value
net/tap: rework tap_set_sndbuf()
net/tap: rework sndbuf handling
net/tap: introduce net_tap_setup()
net/tap: move vhost fd initialization to net_tap_new()
net/tap: finalize net_tap_set_fd() logic
migration: add MIG_EVENT_PRE_INCOMING
net/tap: postpone tap setup to pre-incoming
qapi: add interface for backend-transfer virtio-net/tap migration
virtio-net: support backend-transfer migration for virtio-net/tap
tests/functional: add skipWithoutSudo() decorator
tests/functional: add test_x86_64_tap_migration
hw/net/virtio-net.c | 138 +++++-
include/migration/misc.h | 1 +
include/net/tap.h | 5 +
include/qapi/util.h | 17 +
migration/migration.c | 8 +-
migration/options.c | 27 +
migration/options.h | 2 +
net/tap-bsd.c | 3 +-
net/tap-linux.c | 19 +-
net/tap-solaris.c | 3 +-
net/tap-stub.c | 3 +-
net/tap-win32.c | 5 +
net/tap.c | 467 ++++++++++++++----
net/tap_int.h | 4 +-
qapi/migration.json | 47 +-
tests/functional/qemu_test/decorators.py | 16 +
tests/functional/test_x86_64_tap_migration.py | 344 +++++++++++++
17 files changed, 974 insertions(+), 135 deletions(-)
create mode 100644 tests/functional/test_x86_64_tap_migration.py
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2.48.1
