[libvirt] [PATCH v3 4/5] qemu: add support for Direct Mode for Hyper-V Synthetic timers

[Ján Tomko]

On Tue, Aug 06, 2019 at 07:52:35AM +0200, Vitaly Kuznetsov wrote:
>QEMU-4.1 supports 'Direct Mode' for Hyper-V synthetic timers
>(hv-stimer-direct CPU flag): Windows guests can request that timer
>expiration notifications are delivered as normal interrupts (and not
>VMBus messages). This is used by Hyper-V on KVM.
>
>Signed-off-by: Vitaly Kuznetsov <vkuznets at redhat.com>
>---
> src/qemu/qemu_command.c             | 12 ++++++++----
> src/qemu/qemu_process.c             | 20 ++++++++++++++++++--
> tests/qemuxml2argvdata/hyperv.args  |  4 ++--
> tests/qemuxml2argvdata/hyperv.xml   |  4 +++-
> tests/qemuxml2xmloutdata/hyperv.xml |  4 +++-
> 5 files changed, 34 insertions(+), 10 deletions(-)
>
>diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
>index c8494de785..af913dba34 100644
>--- a/src/qemu/qemu_command.c
>+++ b/src/qemu/qemu_command.c
>@@ -7152,10 +7152,10 @@ qemuBuildCpuCommandLine(virCommandPtr cmd,
>     }
>
>     if (def->features[VIR_DOMAIN_FEATURE_HYPERV] == VIR_TRISTATE_SWITCH_ON) {
>-        const char *hvPrefix = "hv-";
>+        const char *hvDelimiter = "-";
>
>         if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_CANONICAL_CPU_FEATURES))
>-            hvPrefix = "hv_";
>+            hvDelimiter = "_";
>
>         for (i = 0; i < VIR_DOMAIN_HYPERV_LAST; i++) {
>             switch ((virDomainHyperv) i) {
>@@ -7172,9 +7172,13 @@ qemuBuildCpuCommandLine(virCommandPtr cmd,
>             case VIR_DOMAIN_HYPERV_IPI:
>             case VIR_DOMAIN_HYPERV_EVMCS:
>                 if (def->hyperv_features[i] == VIR_TRISTATE_SWITCH_ON)
>-                    virBufferAsprintf(&buf, ",%s%s",
>-                                      hvPrefix,
>+                    virBufferAsprintf(&buf, ",hv%s%s",
>+                                      hvDelimiter,
>                                       virDomainHypervTypeToString(i));
>+                if ((i == VIR_DOMAIN_HYPERV_STIMER) &&
>+                    (def->hyperv_stimer_direct == VIR_TRISTATE_SWITCH_ON))
>+                    virBufferAsprintf(&buf, ",hv%sstimer%sdirect", hvDelimiter,
>+                                      hvDelimiter);

IIUC this feature will be introduced in QEMU 4.1.0 which is the one
where we stop using the aliases with underscores, so this can be
",hv-stimer-direct" and the hvDelimiter changes are not needed.

With that changed:

Reviewed-by: Ján Tomko <jtomko at redhat.com>

Jano
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 488 bytes
Desc: not available
URL: <http://listman.redhat.com/archives/libvir-list/attachments/20190806/8d7d6193/attachment-0001.sig>