Implements alternative way for hot-adding CPU using cpu-add QMP command, which could be useful until it would be possible to add CPUs via device_add.
To hot-add CPU use following command from qmp-shell: cpu-add id=[0..max-cpus - 1) git tree for testing: https://github.com/imammedo/qemu/tree/cpu_add.v9 based on qom-cpu tree v9->v7: * replace machine.cpu-model option with cpu_model field in QEMUMachine * x86: set default cpu_model statically in each machine and get it from there if user haven't provided it. v8->v7: * skip already applied patches * split adding hot_add_cpu hook into separate function * add cpu-model machine option and use QemuOpts for getting it during CPU hotplug. v7->v6: * skip already applied patches * rename icc-bus instance name to "icc" * pass icc_bridge from board as argument down CPU creation call chain, instead of dynamically resolving it for each CPU. v6->v5: * override hot_add_cpu hook statically * extend and use memory_region_find() in IOAPIC * s/signal_cpu_creation/tcg_signal_cpu_creation/ * add "since 1.5 to cpu-addQAPI schema description v5->v4: * style fixes * new helper qemu_for_each_cpu() * switch to qemu_for_each_cpu() in cpu_exists() * "pc: update rtc ..." patch make depend it on "mc146818rtc: QOM'ify" and use QOM cast style * call CPU added notifier right before CPU becomes runable * s/resume_vcpu/cpu_resume/ * acpi/piix4: add spec documentation for QEMU<->Seabios CPU hotplug interface * use error_propagate() in pc_new_cpu() * skip cpu_exists() check in apic-id property setter if new value is the same as current * embed icc-bus inside icc-bridge and use qbus_create_inplace() * move include/hw/i386/icc_bus.h into include/hw/cpu/ * make missing icc-bus fatal error for softmmu target * split "move APIC to ICC bus" and "move IOAPIC to ICC bus" on smaller patches * use qdev_get_parent_bus() to get parent bus * split "add cpu-add command..." on smaller patches v4->v3: * 'id' in cpu-add command will be a thread number instead of APIC ID * split off resume_vcpu() into separate patch * move notifier from rtc code into pc.c v2->v3: * use local error & propagate_error() instead of operating on passed in errp in several places * replace CPUClass.get_firmware_id() with CPUClass.get_arch_id() * leave IOAPIC creation to board and just set bus to icc-bus * include kvm-stub.o in cpu libary if no KVM is configured * create resume_vcpu() stub and include it in libqemustub, and use it directly instead of CPU method * acpi_piix4: s/cpu_add_notifier/cpu_added_notifier/ v1->v2: * generalize cpu sync to KVM, resume and hot-plug notification and invoke them form CPUClass, to make available to all targets. * introduce cpu_exists() and CPUClass.get_firmware_id() and use the last one in acpi_piix to make code target independent. * move IOAPIC to ICC bus, it was suggested and easy to convert. * leave kvmvapic as SysBusDevice, it doesn't affect hot-plug and created only once for all APIC instances. I haven't found yet good/clean enough way to convert it to ICCDevice. May be follow-up though. * split one big ICC patch into several, one per converted device * add cpu_hot_add hook to machine and implement it for target-i386, instead of adding stabs. Could be used by other targets to implement cpu-add. * pre-allocate links<CPU> for all possible CPUs and make them available at /machine/icc-bridge/cpu[0..N] QOM path, so users could find out possible/free CPU IDs to use in cpu-add command. Igor Mammedov (5): add hot_add_cpu hook to QEMUMachine QMP: add cpu-add command add cpu_model to QEMUMachine target-i386: get default cpu_model from QEMUMachine target-i386: implement machine->hot_add_cpu hook hw/i386/pc.c | 32 +++++++++++++++++++++++--------- hw/i386/pc_piix.c | 17 +++++++++++++++-- hw/i386/pc_q35.c | 3 +++ include/hw/boards.h | 2 ++ include/hw/i386/pc.h | 1 + qapi-schema.json | 13 +++++++++++++ qmp-commands.hx | 23 +++++++++++++++++++++++ qmp.c | 10 ++++++++++ target-i386/cpu.h | 6 ++++++ vl.c | 6 ++++++ 10 files changed, 102 insertions(+), 11 deletions(-)
