Changes from v7->v8:
* Patch 3: Rather than using cpu_index to set cpu_num temporarily, squash
in pieces from other patches -- specifically next_cpu_id and move of
cpu_exec_init to realizefn (David)
* Patch 4: New patch, splits out toleration of max_cpus (Igor)
* Patch 5:
* use hotplug_dev instead of qdev_get_machine (Igor)
* Add missing g_free(name) (Igor)
* Patch 6:
* Change s390_new_cpu to take cpu_model parm. Move to helper.c, call
s390_new_cpu from cpu_s390x_init. (David)
* s/local_err/err/ (David)
* Drop getter routine for id property, move some sanity checking from
setter to realize (David)
* Drop unnecessary unref (David)
**************
As discussed in the KVM call, we will go ahead with cpu_add for
s390x to get cpu hotplug functionality in s390x now, until
architectures that require a more robust hotplug interface
settle on a design.
To configure a guest with 2 CPUs online at
boot and 4 maximum:
qemu -smp 2,maxcpus=4
Or, when using libvirt:
<domain>
...
<vcpu current="2">4</vcpu>
...
</domain>
To subsequently hotplug a CPU:
Issue 'cpu-add <id>' from qemu monitor, or use virsh setvcpus --count <n>
<domain>, where <n> is the total number of desired guest CPUs.
At this point, the guest must bring the CPU online for use -- This can be
achieved via "echo 1 > /sys/devices/system/cpu/cpuX/online" or via a management
tool like cpuplugd.
This patch set is based on work previously done by Jason Herne.
Matthew Rosato (7):
s390x/cpu: Cleanup init in preparation for hotplug
s390x/cpu: Set initial CPU state in common routine
s390x/cpu: Get rid of side effects when creating a vcpu
s390x/cpu: Tolerate max_cpus
s390x/cpu: Add CPU property links
s390x/cpu: Add error handling to cpu creation
s390x/cpu: Allow hotplug of CPUs
hw/s390x/s390-virtio-ccw.c | 49 ++++++++++++++++++++++++++-
hw/s390x/s390-virtio.c | 36 +++++++++++---------
hw/s390x/s390-virtio.h | 2 +-
target-s390x/cpu-qom.h | 3 ++
target-s390x/cpu.c | 83 +++++++++++++++++++++++++++++++++++++++++++---
target-s390x/cpu.h | 2 ++
target-s390x/helper.c | 42 +++++++++++++++++++++--
7 files changed, 192 insertions(+), 25 deletions(-)
--
1.9.1
