[PATCH v2 00/10] migration: New postcopy state, and some cleanups

[Peter Xu <peterx@redhat.com>]

v2:
- Collect tags
- Patch 3
  - cover all states in migration_postcopy_is_alive()
- Patch 4 (old)
  - English changes [Fabiano]
  - Split the migration_incoming_state_setup() cleanup into a new patch
    [Fabiano]
  - Drop RECOVER_SETUP in fill_destination_migration_info() [Fabiano]
  - Keep using explicit state check in migrate_fd_connect() for resume
    [Fabiano]
- New patches
  - New doc update: "migration/docs: Update postcopy recover session for
    SETUP phase"
  - New test case: last four patches

v1: https://lore.kernel.org/r/20240612144228.1179240-1-peterx@redhat.com

The major goal of this patchset is patch 5, which introduced a new postcopy
state so that we will send an event in postcopy reconnect failures that
Libvirt would prefer to have.  There's more information for that issue in
the commit message alone.

Patch 1-2 are cleanups that are not directly relevant but I found/stored
that could be good to have.  I made it simple by putting them together in
one thread to make patch management easier, but I can send them separately
when necessary.

Patch 3 is also a cleanup, but will be needed for patch 4 as dependency.

Patch 4-5 is the core patches.

Patch 6 updates doc for the new state.

Patch 7-10 adds a new test for the new state.

Comments welcomed, thanks.

CI: https://gitlab.com/peterx/qemu/-/pipelines/1335604588
    (check-dco & check-patch fail to git-fetch, but doesn't look relevant)

Peter Xu (10):
  migration/multifd: Avoid the final FLUSH in complete()
  migration: Rename thread debug names
  migration: Use MigrationStatus instead of int
  migration: Cleanup incoming migration setup state change
  migration/postcopy: Add postcopy-recover-setup phase
  migration/docs: Update postcopy recover session for SETUP phase
  tests/migration-tests: Drop most WIN32 ifdefs for postcopy failure
    tests
  tests/migration-tests: Always enable migration events
  tests/migration-tests: Verify postcopy-recover-setup status
  tests/migration-tests: Cover postcopy failure on reconnect

 docs/devel/migration/postcopy.rst |  31 +++++----
 qapi/migration.json               |   4 ++
 migration/migration.h             |   9 +--
 migration/postcopy-ram.h          |   3 +
 tests/qtest/migration-helpers.h   |   2 +
 migration/colo.c                  |   2 +-
 migration/migration.c             |  98 ++++++++++++++++++--------
 migration/multifd.c               |   6 +-
 migration/postcopy-ram.c          |  10 ++-
 migration/ram.c                   |   4 --
 migration/savevm.c                |   6 +-
 tests/qtest/migration-helpers.c   |  20 ++++++
 tests/qtest/migration-test.c      | 110 ++++++++++++++++++++++++------
 13 files changed, 223 insertions(+), 82 deletions(-)

-- 
2.45.0