Re: [PATCH v5 untested] kvm: better MWAIT emulation for guests

Michael S. Tsirkin
2017-03-21T03:22:20Z

On Fri, Mar 17, 2017 at 09:23:56AM -0400, Gabriel L. Somlo wrote:
> OK, now on to Radim's test, on the MacPro1,1:
>
> [kvm-unit-tests]$ time TIMEOUT=20 ./x86-run x86/mwait.flat -append '240 1 1'
> timeout -k 1s --foreground 20 qemu-kvm -nodefaults -enable-kvm -device pc-testdev -device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio -device pci-testdev -kernel x86/mwait.flat -append 240 1 1
> enabling apic
> PASS: resumed from mwait 10000 times
> SUMMARY: 1 tests
>
> real 0m0.746s
> user 0m0.542s
> sys 0m0.215s
> [kvm-unit-tests]$ time TIMEOUT=20 ./x86-run x86/mwait.flat -append '240 1 0'
> timeout -k 1s --foreground 20 qemu-kvm -nodefaults -enable-kvm -device pc-testdev -device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio -device pci-testdev -kernel x86/mwait.flat -append 240 1 0
> enabling apic
> PASS: resumed from mwait 10000 times
> SUMMARY: 1 tests
>
> real 0m0.743s
> user 0m0.528s
> sys 0m0.226s
> [kvm-unit-tests]$ time TIMEOUT=20 ./x86-run x86/mwait.flat -append '240 1 1' -smp 2
> timeout -k 1s --foreground 20 qemu-kvm -nodefaults -enable-kvm -device pc-testdev -device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio -device pci-testdev -kernel x86/mwait.flat -append 240 1 1 -smp 2
> enabling apic
> enabling apic
> FAIL: resumed from mwait 10150 times
> SUMMARY: 1 tests, 1 unexpected failures
>
> real 0m0.745s
> user 0m0.545s
> sys 0m0.214s
> [kvm-unit-tests]$ time TIMEOUT=20 ./x86-run x86/mwait.flat -append '240 1 0' -smp 2
> timeout -k 1s --foreground 20 qemu-kvm -nodefaults -enable-kvm -device pc-testdev -device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio -device pci-testdev -kernel x86/mwait.flat -append 240 1 0 -smp 2
> enabling apic
> enabling apic
> FAIL: resumed from mwait 10116 times
> SUMMARY: 1 tests, 1 unexpected failures
>
> real 0m0.744s
> user 0m0.541s
> sys 0m0.217s
>
> HTH,
> --Gabriel

Weird. How can it go above 10000? Radim - any idea?

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MST