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

[Vitaly Kuznetsov]

Ján Tomko <jtomko at redhat.com> writes:

> One more thing, qemuxml2argvtest is using DO_TEST:
>     DO_TEST("hyperv", NONE);
>     DO_TEST("hyperv-off", NONE);
>     DO_TEST("hyperv-panic", NONE);
> which manually enumarate the used QEMU capabilities (although there are
> none here)
>
> DO_TEST_CAPS_LATEST is the way to test against QEMU capabilites
> gathered from a real binary - if you use that macro for testing,
> it will have the QEMU_CAPS_CANONICAL_CPU_FEATURES capability and all the
> included features will use '-' instead of '_' as the separator.
>

Forgive me my ignorance (and long reply times), is the idea aimed at
removing "hvPrefix" machinery from qemuBuildCpuCommandLine() completely
- probably in favor of hardcorded '-' delimiters?

I tried switching to DO_TEST_CAPS_LATEST in qemuxml2argvtest and after
renaming
tests/qemuxml2argvdata/hyperv{-off,-panic}.args to
tests/qemuxml2argvdata/hyperv{,-off,-panic}.x86_64-latest.args
to make the test run, I'm getting the following:

In '/home/vitty/workspace/Upstream/libvirt/tests/qemuxml2argvdata/hyperv.x86_64-latest.args':
Offset 292
Expect [QEMUGuest1 -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' -m 214 -realtime mlock=off -smp 6,sockets=6,cores=1,threads=1 -uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 -display none -no-user-config -nodefaults -chardev socket,id=charmonitor,path=/tmp/lib/domain--1-QEMUGuest1/monitor.sock,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc -no-shutdown -usb]
Actual [guest=QEMUGuest1,debug-threads=on -S -object secret,id=masterKey0,format=raw,file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes -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' -m 214 -overcommit mem-lock=off -smp 6,sockets=6,cores=1,threads=1 -uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 -display none -no-user-config -nodefaults -chardev socket,id=charmonitor,fd=1729,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc -no-shutdown -boot strict=on -device piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2 -sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny -msg timestamp=on]
 
I can, probably, add all the missing stuff but I'm not sure it's the
right way to go in the first place :-)

What if we just add QEMU_CAPS_CANONICAL_CPU_FEATURES to DO_TEST:

diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 71a36ff63a..f88d45f4e6 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -7152,11 +7152,6 @@ qemuBuildCpuCommandLine(virCommandPtr cmd,
     }
 
     if (def->features[VIR_DOMAIN_FEATURE_HYPERV] == VIR_TRISTATE_SWITCH_ON) {
-        const char *hvPrefix = "hv-";
-
-        if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_CANONICAL_CPU_FEATURES))
-            hvPrefix = "hv_";
-
         for (i = 0; i < VIR_DOMAIN_HYPERV_LAST; i++) {
             switch ((virDomainHyperv) i) {
             case VIR_DOMAIN_HYPERV_RELAXED:
@@ -7172,8 +7167,7 @@ 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",
                                       virDomainHypervTypeToString(i));
                 break;
 
diff --git a/tests/qemuxml2argvdata/hyperv.args b/tests/qemuxml2argvdata/hyperv.args
index 086adaa349..d09d8acdff 100644
--- a/tests/qemuxml2argvdata/hyperv.args
+++ b/tests/qemuxml2argvdata/hyperv.args
@@ -11,9 +11,9 @@ QEMU_AUDIO_DRV=none \
 -name QEMUGuest1 \
 -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' \
+-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' \
 -m 214 \
 -realtime mlock=off \
 -smp 6,sockets=6,cores=1,threads=1 \
diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index c166fd18d6..d13c7c8b56 100644
--- a/tests/qemuxml2argvtest.c
+++ b/tests/qemuxml2argvtest.c
@@ -911,9 +911,9 @@ mymain(void)
     DO_TEST_CAPS_VER("kvmclock+eoi-disabled", "4.0.0");
     DO_TEST_CAPS_LATEST("kvmclock+eoi-disabled");
 
-    DO_TEST("hyperv", NONE);
-    DO_TEST("hyperv-off", NONE);
-    DO_TEST("hyperv-panic", NONE);
+    DO_TEST("hyperv", QEMU_CAPS_CANONICAL_CPU_FEATURES);
+    DO_TEST("hyperv-off", QEMU_CAPS_CANONICAL_CPU_FEATURES);
+    DO_TEST("hyperv-panic", QEMU_CAPS_CANONICAL_CPU_FEATURES);
 
     DO_TEST("kvm-features", NONE);
     DO_TEST("kvm-features-off", NONE);

-- 
Vitaly