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Subject[PATCH v7 0/3] KVM: perf: kvm events analysis tool
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From: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>

Changelog:
- rebased it on Arnaldo's git tree perf/core branch

the change from Arnaldo's comments:
- directly get event from evsel->tp_format
- remove die() and return the proper error code
- rename thread->private to thread->priv

the change from David's comments:
- use is_valid_tracepoint instead of kvm_events_exist

This patchset introduces a perf-based tool (perf kvm stat record/report)
which can analyze kvm events more smartly. Below is the presentation slice
on 2012 Japan LinuxCon:
http://events.linuxfoundation.org/images/stories/pdf/lcjp2012_guangrong.pdf
You can get more details from it. If any questions/comments, please feel free
to let us know.

This patchset is based on Arnaldo's git tree perf/core branch, and patch 2
is just doing the "improvement" work, which can be picked up independently.


Usage:
- kvm stat
run a command and gather performance counter statistics, it is the alias of
perf stat

- trace kvm events:
perf kvm stat record, or, if other tracepoints are interesting as well, we
can append the events like this:
perf kvm stat record -e kvm:*
If many guests are running, we can track the specified guest by using -p or
--pid

- show the result:
perf kvm stat report

The output example is following:
# pgrep qemu-kvm
26071
32253
32564

total 3 guests are running on the host

Then, track the guest whose pid is 26071:
# ./perf kvm stat record -p 26071
^C[ perf record: Woken up 9 times to write data ]
[ perf record: Captured and wrote 24.903 MB perf.data.guest (~1088034 samples) ]

See the vmexit events:
# ./perf kvm stat report --event=vmexit

Analyze events for all VCPUs:

VM-EXIT Samples Samples% Time% Avg time

APIC_ACCESS 65381 66.58% 5.95% 37.72us ( +- 6.54% )
EXTERNAL_INTERRUPT 16031 16.32% 3.06% 79.11us ( +- 7.34% )
CPUID 5360 5.46% 0.06% 4.50us ( +- 35.07% )
HLT 4496 4.58% 90.75% 8360.34us ( +- 5.22% )
EPT_VIOLATION 2667 2.72% 0.04% 5.49us ( +- 5.05% )
PENDING_INTERRUPT 2242 2.28% 0.03% 5.25us ( +- 2.96% )
EXCEPTION_NMI 1332 1.36% 0.02% 6.53us ( +- 6.51% )
IO_INSTRUCTION 383 0.39% 0.09% 93.39us ( +- 40.92% )
CR_ACCESS 310 0.32% 0.00% 6.10us ( +- 3.95% )

Total Samples:98202, Total events handled time:41419293.63us.

See the mmio events:
# ./perf kvm stat report --event=mmio

Analyze events for all VCPUs:

MMIO Access Samples Samples% Time% Avg time

0xfee00380:W 58686 90.21% 15.67% 4.95us ( +- 2.96% )
0xfee00300:R 2124 3.26% 1.48% 12.93us ( +- 14.75% )
0xfee00310:W 2124 3.26% 0.34% 3.00us ( +- 1.33% )
0xfee00300:W 2123 3.26% 82.50% 720.68us ( +- 10.24% )

Total Samples:65057, Total events handled time:1854470.45us.

See the ioport event:
# ./perf kvm stat report --event=ioport

Analyze events for all VCPUs:

IO Port Access Samples Samples% Time% Avg time

0xc090:POUT 383 100.00% 100.00% 89.00us ( +- 42.94% )

Total Samples:383, Total events handled time:34085.56us.

And, --vcpu is used to track the specified vcpu and --key is used to sort the
result:
# ./perf kvm stat report --event=vmexit --vcpu=0 --key=time

Analyze events for VCPU 0:

VM-EXIT Samples Samples% Time% Avg time

HLT 551 5.05% 94.81% 9501.72us ( +- 12.52% )
EXTERNAL_INTERRUPT 1390 12.74% 2.39% 94.80us ( +- 20.92% )
APIC_ACCESS 6186 56.68% 2.62% 23.41us ( +- 23.62% )
IO_INSTRUCTION 17 0.16% 0.01% 20.39us ( +- 22.33% )
EXCEPTION_NMI 94 0.86% 0.01% 6.07us ( +- 7.13% )
PENDING_INTERRUPT 199 1.82% 0.02% 5.48us ( +- 4.36% )
CR_ACCESS 52 0.48% 0.00% 4.89us ( +- 4.09% )
EPT_VIOLATION 2057 18.85% 0.12% 3.15us ( +- 1.33% )
CPUID 368 3.37% 0.02% 2.82us ( +- 2.79% )

Total Samples:10914, Total events handled time:5521782.02us.


Dong Hao (3):
KVM: x86: export svm/vmx exit code and vector code to userspace
KVM: x86: trace mmio begin and complete
KVM: perf: kvm events analysis tool

arch/x86/include/asm/kvm_host.h | 36 +-
arch/x86/include/asm/svm.h | 205 +++++---
arch/x86/include/asm/vmx.h | 126 +++--
arch/x86/kvm/trace.h | 89 ----
arch/x86/kvm/x86.c | 32 +-
include/trace/events/kvm.h | 37 ++
tools/perf/Documentation/perf-kvm.txt | 30 +-
tools/perf/MANIFEST | 3 +
tools/perf/builtin-kvm.c | 889 ++++++++++++++++++++++++++++++++-
tools/perf/util/header.c | 54 ++-
tools/perf/util/header.h | 1 +
tools/perf/util/thread.h | 2 +
12 files changed, 1264 insertions(+), 240 deletions(-)

--
1.7.2.5



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