On 1/12/23 12:52, Thomas Huth wrote:
On 05/01/2023 15.53, Pierre Morel wrote:
When the guest asks to change the polarity this change
is forwarded to the admin using QAPI.
The admin is supposed to take according decisions concerning
CPU provisioning.
I somehow doubt that an average admin will monitor QEMU for such events
... so this rather should be handled by upper layers like libvirt one day?
Yes.
Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
---
qapi/machine-target.json | 21 +++++++++++++++++++++
hw/s390x/cpu-topology.c | 2 ++
2 files changed, 23 insertions(+)
diff --git a/qapi/machine-target.json b/qapi/machine-target.json
index 927618a78f..10235cfb45 100644
--- a/qapi/machine-target.json
+++ b/qapi/machine-target.json
@@ -437,3 +437,24 @@
'returns': ['S390CpuTopology'],
'if': { 'all': [ 'TARGET_S390X', 'CONFIG_KVM' ] }
}
+
+##
+# @POLARITY_CHANGE:
I'd maybe rather call it CPU_POLARITY_CHANGE ... in case "polarity" is
one day also used for some other devices.
OK, right.
+#
+# Emitted when the guest asks to change the polarity.
+#
+# @polarity: polarity specified by the guest
Please elaborate: Where does the value come from (the PTF instruction)?
Which values are possible?
Yes what about:
# @polarity: the guest can specify with the PTF instruction a horizontal
# or a vertical polarity.
# On horizontal polarity the host is expected to provision
# the vCPU equally.
# On vertical polarity the host can provision each vCPU
# differently
# The guest can get information on the provisioning with
# the STSI(15) instruction.
Regards,
Pierre
--
Pierre Morel
IBM Lab Boeblingen
