Define a new qemu initialization phase called 'precreate' which occurs before most backends or devices have been created. The only exception is monitor and qtest devices and their associated chardevs.
QEMU runs in the main loop during this phase. Monitor connections are active and can receive migration configuration commands. QEMU starts listening on the normal migration URI during this phase, which can come from either the QEMU command line or from a migrate_incoming command. Thus the user can issue query-migrate to get the socket-address for dynamically allocated port numbers during precreate. In this series QEMU passes through and does not linger in the precreate phase, and the user sees no change in behavior. The cpr-transfer series will linger in the phase for an incoming CPR operation, and exit the phase when the migrate command is send to source QEMU and causes destination QEMU to read CPR state. A future series may wish to add a command-line argument and monitor command that enters and exits the precreate phase for general purpose use. That would enable the user to issue monitor commands that specify backend creation parameters. Now that both the monitor and migration are initialized early, one could implement a future scheme in which very few parameters are passed on the command line, and all backend and device creation parameters are passed in the migration stream. Patches 1-5 untangle dependencies between accelerator and migration initialization, allowing the latter to be called earlier. Currently configure_accelerators chooses the accelerator, defines compatability properties needed to initialize migration, and creates the machine in accel_init_machine. The patches split configure_accelerators into a first part which probes for accelerators and defines properties, and a second part which creates the machine. The second part is called after the precreate phase. The patches also set machine options earlier, so they are known when migration is initialized. Patch 6 defines the boundaries of the precreate phase. Patches 7-12 define and use helper functions to extract monitor and qtest options from the command line, find their associated chardevs, and initialize the monitor and qtest devices early, prior to qemu_create_early_backends. Patches 13-14 contain miscellany. Steve Sistare (14): accel: encapsulate search state accel: accel preinit function accel: split configure_accelerators accel: set accelerator and machine props earlier migration: init and listen during precreate vl: precreate phase monitor: chardev name qom: get properties qemu-option: filtered foreach qemu-options: pass object to filter monitor: connect in precreate qtest: connect in precreate net: cleanup for precreate phase migration: allow commands during precreate and preconfig accel/accel-system.c | 2 - accel/kvm/kvm-all.c | 58 +++++---- accel/xen/xen-all.c | 11 +- hmp-commands.hx | 2 + include/monitor/monitor.h | 1 + include/qapi/visitor.h | 1 + include/qemu/accel.h | 1 + include/qemu/option.h | 5 + include/qom/object_interfaces.h | 8 ++ monitor/monitor.c | 21 ++++ net/net.c | 4 +- qapi/migration.json | 16 ++- qapi/misc.json | 3 +- qom/object_interfaces.c | 27 ++-- system/vl.c | 270 ++++++++++++++++++++++++++++++---------- target/i386/nvmm/nvmm-all.c | 10 +- target/i386/whpx/whpx-all.c | 14 ++- util/qemu-option.c | 25 ++++ 18 files changed, 358 insertions(+), 121 deletions(-) -- 1.8.3.1
