[libvirt] [PATCH v2 7/8] qemu: add support for Direct Mode for Hyper-V Synthetic timers

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(a)redhat.com&gt; --- 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 fee51158a9..be5777023c 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -7151,10 +7151,10 @@ 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) { @@ -7171,9 +7171,13 @@ 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); break; case VIR_DOMAIN_HYPERV_SPINLOCKS: diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c index 0ee97e2296..ad1a75bfee 100644 --- a/src/qemu/qemu_process.c +++ b/src/qemu/qemu_process.c @@ -4111,10 +4111,26 @@ qemuProcessVerifyHypervFeatures(virDomainDefPtr def, rc = virCPUDataCheckFeature(cpu, cpuFeature); VIR_FREE(cpuFeature); - if (rc < 0) + if (rc < 0) { return -1; - else if (rc == 1) + } else if (rc == 1) { + if (i == VIR_DOMAIN_HYPERV_STIMER) { + if (def->hyperv_stimer_direct != VIR_TRISTATE_SWITCH_ON) + continue; + + rc = virCPUDataCheckFeature(cpu, "hv-stimer-direct"); + if (rc < 0) + return -1; + else if (rc == 1) + continue; + + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, + _("host doesn't support hyperv stimer '%s' feature"), + "direct"); + return -1; + } continue; + } switch ((virDomainHyperv) i) { case VIR_DOMAIN_HYPERV_RELAXED: diff --git a/tests/qemuxml2argvdata/hyperv.args b/tests/qemuxml2argvdata/hyperv.args index 086adaa349..8040da9caa 100644 --- a/tests/qemuxml2argvdata/hyperv.args +++ b/tests/qemuxml2argvdata/hyperv.args @@ -12,8 +12,8 @@ QEMU_AUDIO_DRV=none \ -S \ -machine pc,accel=tcg,usb=off,dump-guest-core=off \ -cpu 'qemu32,hv_relaxed,hv_vapic,hv-spinlocks=0x2fff,hv_vpindex,hv_runtime,\ -hv_synic,hv_stimer,hv_reset,hv-vendor-id=KVM Hv,hv_frequencies,\ -hv_reenlightenment,hv_tlbflush,hv_ipi,hv_evmcs' \ +hv_synic,hv_stimer,hv_stimer_direct,hv_reset,hv-vendor-id=KVM Hv,\ +hv_frequencies,hv_reenlightenment,hv_tlbflush,hv_ipi,hv_evmcs' \ -m 214 \ -realtime mlock=off \ -smp 6,sockets=6,cores=1,threads=1 \ diff --git a/tests/qemuxml2argvdata/hyperv.xml b/tests/qemuxml2argvdata/hyperv.xml index c6feaed528..ae0f934f76 100644 --- a/tests/qemuxml2argvdata/hyperv.xml +++ b/tests/qemuxml2argvdata/hyperv.xml @@ -17,7 +17,9 @@ <vpindex state='on'/> <runtime state='on'/> <synic state='on'/> - <stimer state='on'/> + <stimer state='on'> + <direct state='on'/> + </stimer> <reset state='on'/> <vendor_id state='on' value='KVM Hv'/> <frequencies state='on'/> diff --git a/tests/qemuxml2xmloutdata/hyperv.xml b/tests/qemuxml2xmloutdata/hyperv.xml index 5510d3dfad..2e4b43d4c6 100644 --- a/tests/qemuxml2xmloutdata/hyperv.xml +++ b/tests/qemuxml2xmloutdata/hyperv.xml @@ -17,7 +17,9 @@ <vpindex state='on'/> <runtime state='on'/> <synic state='on'/> - <stimer state='on'/> + <stimer state='on'> + <direct state='on'/> + </stimer> <reset state='on'/> <vendor_id state='on' value='KVM Hv'/> <frequencies state='on'/> -- 2.20.1