我尝试perf在我的 Linux 系统中运行，但 WSL2 和 virtual-box 6.1 未检测到硬件系统中的 PMU。
因此，我安装qemu-system-x86_64在 Linux VM 中，并尝试在模拟模式下运行 QEMU 以使用模拟的 PMU。
但是在模拟模式下运行 QEMU 时，我仍然收到内核日志，提示“没有 PMU 计数器”。
我尝试qemu-system-x86_64用-cpu IvyBridgeor运行-cpu BroadWell，但没有人工作。
我运行qemu -cpu help并得到了以下受支持的 CPU 型号。
VirtualBox:/mnt$ qemu-system-x86_64 -cpu help
Available CPUs:
x86 486 (alias configured by machine type)
x86 486-v1
x86 Broadwell (alias configured by machine type)
x86 Broadwell-IBRS (alias of Broadwell-v3)
x86 Broadwell-noTSX (alias of Broadwell-v2)
x86 Broadwell-noTSX-IBRS (alias of Broadwell-v4)
x86 Broadwell-v1 Intel Core Processor (Broadwell)
x86 Broadwell-v2 Intel Core Processor (Broadwell, no TSX)
x86 Broadwell-v3 Intel Core Processor (Broadwell, IBRS)
x86 Broadwell-v4 Intel Core Processor (Broadwell, no TSX, IBRS)
x86 Cascadelake-Server (alias configured by machine type)
x86 Cascadelake-Server-noTSX (alias of Cascadelake-Server-v3)
x86 Cascadelake-Server-v1 Intel Xeon Processor (Cascadelake)
x86 Cascadelake-Server-v2 Intel Xeon Processor (Cascadelake)
x86 Cascadelake-Server-v3 Intel Xeon Processor (Cascadelake)
x86 Conroe (alias configured by machine type)
x86 Conroe-v1 Intel Celeron_4x0 (Conroe/Merom Class Core 2)
x86 Cooperlake (alias configured by machine type)
x86 Cooperlake-v1 Intel Xeon Processor (Cooperlake)
x86 Denverton (alias configured by machine type)
x86 Denverton-v1 Intel Atom Processor (Denverton)
x86 Dhyana (alias configured by machine type)
x86 Dhyana-v1 Hygon Dhyana Processor
x86 EPYC (alias configured by machine type)
x86 EPYC-IBPB (alias of EPYC-v2)
x86 EPYC-Milan (alias configured by machine type)
x86 EPYC-Milan-v1 AMD EPYC-Milan Processor
x86 EPYC-Rome (alias configured by machine type)
x86 EPYC-Rome-v1 AMD EPYC-Rome Processor
x86 EPYC-Rome-v2 AMD EPYC-Rome Processor
x86 EPYC-v1 AMD EPYC Processor
x86 EPYC-v2 AMD EPYC Processor (with IBPB)
x86 EPYC-v3 AMD EPYC Processor
x86 Haswell (alias configured by machine type)
x86 Haswell-IBRS (alias of Haswell-v3)
x86 Haswell-noTSX (alias of Haswell-v2)
x86 Haswell-noTSX-IBRS (alias of Haswell-v4)
x86 Haswell-v1 Intel Core Processor (Haswell)
x86 Haswell-v2 Intel Core Processor (Haswell, no TSX)
x86 Haswell-v3 Intel Core Processor (Haswell, IBRS)
x86 Haswell-v4 Intel Core Processor (Haswell, no TSX, IBRS)
x86 Icelake-Client (alias configured by machine type)
x86 Icelake-Client-noTSX (alias of Icelake-Client-v2)
x86 Icelake-Client-v1 Intel Core Processor (Icelake)
x86 Icelake-Client-v2 Intel Core Processor (Icelake)
x86 Icelake-Server (alias configured by machine type)
x86 Icelake-Server-noTSX (alias of Icelake-Server-v2)
x86 Icelake-Server-v1 Intel Xeon Processor (Icelake)
x86 Icelake-Server-v2 Intel Xeon Processor (Icelake)
x86 IvyBridge (alias configured by machine type)
x86 IvyBridge-IBRS (alias of IvyBridge-v2)
x86 IvyBridge-v1 Intel Xeon E3-12xx v2 (Ivy Bridge)
x86 IvyBridge-v2 Intel Xeon E3-12xx v2 (Ivy Bridge, IBRS)
x86 KnightsMill (alias configured by machine type)
x86 KnightsMill-v1 Intel Xeon Phi Processor (Knights Mill)
x86 Nehalem (alias configured by machine type)
x86 Nehalem-IBRS (alias of Nehalem-v2)
x86 Nehalem-v1 Intel Core i7 9xx (Nehalem Class Core i7)
x86 Nehalem-v2 Intel Core i7 9xx (Nehalem Core i7, IBRS update)
x86 Opteron_G1 (alias configured by machine type)
x86 Opteron_G1-v1 AMD Opteron 240 (Gen 1 Class Opteron)
x86 Opteron_G2 (alias configured by machine type)
x86 Opteron_G2-v1 AMD Opteron 22xx (Gen 2 Class Opteron)
x86 Opteron_G3 (alias configured by machine type)
x86 Opteron_G3-v1 AMD Opteron 23xx (Gen 3 Class Opteron)
x86 Opteron_G4 (alias configured by machine type)
x86 Opteron_G4-v1 AMD Opteron 62xx class CPU
x86 Opteron_G5 (alias configured by machine type)
x86 Opteron_G5-v1 AMD Opteron 63xx class CPU
x86 Penryn (alias configured by machine type)
x86 Penryn-v1 Intel Core 2 Duo P9xxx (Penryn Class Core 2)
x86 SandyBridge (alias configured by machine type)
x86 SandyBridge-IBRS (alias of SandyBridge-v2)
x86 SandyBridge-v1 Intel Xeon E312xx (Sandy Bridge)
x86 SandyBridge-v2 Intel Xeon E312xx (Sandy Bridge, IBRS update)
x86 Skylake-Client (alias configured by machine type)
x86 Skylake-Client-IBRS (alias of Skylake-Client-v2)
x86 Skylake-Client-noTSX-IBRS (alias of Skylake-Client-v3)
x86 Skylake-Client-v1 Intel Core Processor (Skylake)
x86 Skylake-Client-v2 Intel Core Processor (Skylake, IBRS)
x86 Skylake-Client-v3 Intel Core Processor (Skylake, IBRS)
x86 Skylake-Server (alias configured by machine type)
x86 Skylake-Server-IBRS (alias of Skylake-Server-v2)
x86 Skylake-Server-noTSX-IBRS (alias of Skylake-Server-v3)
x86 Skylake-Server-v1 Intel Xeon Processor (Skylake)
x86 Skylake-Server-v2 Intel Xeon Processor (Skylake, IBRS)
x86 Skylake-Server-v3 Intel Xeon Processor (Skylake, IBRS)
x86 Snowridge (alias configured by machine type)
x86 Snowridge-v1 Intel Atom Processor (SnowRidge)
x86 Snowridge-v2 Intel Atom Processor (Snowridge, no MPX)
x86 Westmere (alias configured by machine type)
x86 Westmere-IBRS (alias of Westmere-v2)
x86 Westmere-v1 Westmere E56xx/L56xx/X56xx (Nehalem-C)
x86 Westmere-v2 Westmere E56xx/L56xx/X56xx (IBRS update)
x86 athlon (alias configured by machine type)
x86 athlon-v1 QEMU Virtual CPU version 2.5+
x86 core2duo (alias configured by machine type)
x86 core2duo-v1 Intel(R) Core(TM)2 Duo CPU T7700 @ 2.40GHz
x86 coreduo (alias configured by machine type)
x86 coreduo-v1 Genuine Intel(R) CPU T2600 @ 2.16GHz
x86 kvm32 (alias configured by machine type)
x86 kvm32-v1 Common 32-bit KVM processor
x86 kvm64 (alias configured by machine type)
x86 kvm64-v1 Common KVM processor
x86 n270 (alias configured by machine type)
x86 n270-v1 Intel(R) Atom(TM) CPU N270 @ 1.60GHz
x86 pentium (alias configured by machine type)
x86 pentium-v1
x86 pentium2 (alias configured by machine type)
x86 pentium2-v1
x86 pentium3 (alias configured by machine type)
x86 pentium3-v1
x86 phenom (alias configured by machine type)
x86 phenom-v1 AMD Phenom(tm) 9550 Quad-Core Processor
x86 qemu32 (alias configured by machine type)
x86 qemu32-v1 QEMU Virtual CPU version 2.5+
x86 qemu64 (alias configured by machine type)
x86 qemu64-v1 QEMU Virtual CPU version 2.5+
x86 base base CPU model type with no features enabled
x86 host KVM processor with all supported host features
x86 max Enables all features supported by the accelerator in the current host
Recognized CPUID flags:
3dnow 3dnowext 3dnowprefetch abm ace2 ace2-en acpi adx aes amd-no-ssb
amd-ssbd amd-stibp apic arat arch-capabilities avic avx avx2
avx512-4fmaps avx512-4vnniw avx512-bf16 avx512-vpopcntdq avx512bitalg
avx512bw avx512cd avx512dq avx512er avx512f avx512ifma avx512pf
avx512vbmi avx512vbmi2 avx512vl avx512vnni bmi1 bmi2 cid cldemote clflush
clflushopt clwb clzero cmov cmp-legacy core-capability cr8legacy cx16 cx8
dca de decodeassists ds ds-cpl dtes64 erms est extapic f16c flushbyasid
fma fma4 fpu fsgsbase fsrm fxsr fxsr-opt gfni hle ht hypervisor ia64 ibpb
ibrs ibrs-all ibs intel-pt invpcid invtsc kvm-asyncpf kvm-hint-dedicated
kvm-mmu kvm-nopiodelay kvm-poll-control kvm-pv-eoi kvm-pv-ipi
kvm-pv-sched-yield kvm-pv-tlb-flush kvm-pv-unhalt kvm-steal-time kvmclock
kvmclock kvmclock-stable-bit la57 lahf-lm lbrv lm lwp mca mce md-clear
mds-no misalignsse mmx mmxext monitor movbe movdir64b movdiri mpx msr
mtrr nodeid-msr npt nrip-save nx osvw pae pat pause-filter pbe pcid
pclmulqdq pcommit pdcm pdpe1gb perfctr-core perfctr-nb pfthreshold pge
phe phe-en pku pmm pmm-en pn pni popcnt pschange-mc-no pse pse36 rdctl-no
rdpid rdrand rdseed rdtscp rsba rtm sep sha-ni skinit skip-l1dfl-vmentry
smap smep smx spec-ctrl split-lock-detect ss ssb-no ssbd sse sse2 sse4.1
sse4.2 sse4a ssse3 stibp svm svm-lock svme-addr-chk syscall taa-no tbm
tce tm tm2 topoext tsc tsc-adjust tsc-deadline tsc-scale tsx-ctrl umip
v-vmsave-vmload vaes vgif virt-ssbd vmcb-clean vme vmx vmx-activity-hlt
vmx-activity-shutdown vmx-activity-wait-sipi vmx-apicv-register
vmx-apicv-vid vmx-apicv-x2apic vmx-apicv-xapic vmx-cr3-load-noexit
vmx-cr3-store-noexit vmx-cr8-load-exit vmx-cr8-store-exit vmx-desc-exit
vmx-encls-exit vmx-entry-ia32e-mode vmx-entry-load-bndcfgs
vmx-entry-load-efer vmx-entry-load-pat vmx-entry-load-perf-global-ctrl
vmx-entry-load-rtit-ctl vmx-entry-noload-debugctl vmx-ept vmx-ept-1gb
vmx-ept-2mb vmx-ept-advanced-exitinfo vmx-ept-execonly vmx-eptad
vmx-eptp-switching vmx-exit-ack-intr vmx-exit-clear-bndcfgs
vmx-exit-clear-rtit-ctl vmx-exit-load-efer vmx-exit-load-pat
vmx-exit-load-perf-global-ctrl vmx-exit-nosave-debugctl
vmx-exit-save-efer vmx-exit-save-pat vmx-exit-save-preemption-timer
vmx-flexpriority vmx-hlt-exit vmx-ins-outs vmx-intr-exit vmx-invept
vmx-invept-all-context vmx-invept-single-context
vmx-invept-single-context vmx-invept-single-context-noglobals
vmx-invlpg-exit vmx-invpcid-exit vmx-invvpid vmx-invvpid-all-context
vmx-invvpid-single-addr vmx-io-bitmap vmx-io-exit vmx-monitor-exit
vmx-movdr-exit vmx-msr-bitmap vmx-mtf vmx-mwait-exit vmx-nmi-exit
vmx-page-walk-4 vmx-page-walk-5 vmx-pause-exit vmx-ple vmx-pml
vmx-posted-intr vmx-preemption-timer vmx-rdpmc-exit vmx-rdrand-exit
vmx-rdseed-exit vmx-rdtsc-exit vmx-rdtscp-exit vmx-secondary-ctls
vmx-shadow-vmcs vmx-store-lma vmx-true-ctls vmx-tsc-offset
vmx-unrestricted-guest vmx-vintr-pending vmx-vmfunc
vmx-vmwrite-vmexit-fields vmx-vnmi vmx-vnmi-pending vmx-vpid
vmx-wbinvd-exit vmx-xsaves vmx-zero-len-inject vpclmulqdq waitpkg
wbnoinvd wdt x2apic xcrypt xcrypt-en xgetbv1 xop xsave xsavec xsaveerptr
xsaveopt xsaves xstore xstore-en xtpr
VirtualBox:/mnt$ qemu-system-x86_64 --version
QEMU emulator version 4.2.1 (Debian 1:4.2-3ubuntu6.28)
Copyright (c) 2003-2019 Fabrice Bellard and the QEMU Project developers
那么，是否可以在QEMU的仿真模式下启用PMU计数器（不使用KVM）？
答案1
我认为如果没有内核驱动程序（类似于 KVM）或真正的 PMU 硬件，就无法模拟 PMU。在KVM中，PMU通过内核空间虚拟化perf_event_create_kernel_counter，即处理PMU硬件的内核性能框架。所以WSL性能问题的关键是，hyperV是否支持PMU虚拟化？我对这个问题没有明确的答案，但我认为答案可能是
不。