Re: [PATCH v8 3/3] KVM: perf: kvm events analysis tool

[David Ahern <dsahern@gmail.com>]

On 9/17/12 2:31 AM, Dong Hao wrote:
> From: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
>
> Add 'perf kvm stat' support to analyze kvm vmexit/mmio/ioport smartly
>
> 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 timer:* -a
>
>    If many guests are running, we can track the specified guest by using -p or
>    --pid, -a is used to track events generated by all guests.
>
> - show the result:
>    perf kvm stat report
>
> The output example is following:
> # pgrep qemu
> 13005
> 13059
>
> total 2 guests are running on the host
>
> Then, track the guest whose pid is 13059:
> # ./perf kvm stat record -p 13059
> ^C[ perf record: Woken up 1 times to write data ]
> [ perf record: Captured and wrote 0.253 MB perf.data.guest (~11065 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        460    70.55%     0.01%     22.44us ( +-   1.75% )
>                   HLT         93    14.26%    99.98% 832077.26us ( +-  10.42% )
>    EXTERNAL_INTERRUPT         64     9.82%     0.00%     35.35us ( +-  14.21% )
>     PENDING_INTERRUPT         24     3.68%     0.00%      9.29us ( +-  31.39% )
>             CR_ACCESS          7     1.07%     0.00%      8.12us ( +-   5.76% )
>        IO_INSTRUCTION          3     0.46%     0.00%     18.00us ( +-  11.79% )
>         EXCEPTION_NMI          1     0.15%     0.00%      5.83us ( +-   -nan% )
>
> Total Samples:652, Total events handled time:77396109.80us.
>
> See the mmio events:
> # ./perf kvm stat report --event=mmio
>
>
> Analyze events for all VCPUs:
>
>           MMIO Access    Samples  Samples%     Time%         Avg time
>
>          0xfee00380:W        387    84.31%    79.28%      8.29us ( +-   3.32% )
>          0xfee00300:W         24     5.23%     9.96%     16.79us ( +-   1.97% )
>          0xfee00300:R         24     5.23%     7.83%     13.20us ( +-   3.00% )
>          0xfee00310:W         24     5.23%     2.93%      4.94us ( +-   3.84% )
>
> Total Samples:459, Total events handled time:4044.59us.
>
> See the ioport event:
> # ./perf kvm stat report --event=ioport
>
>
> Analyze events for all VCPUs:
>
>        IO Port Access    Samples  Samples%     Time%         Avg time
>
>           0xc050:POUT          3   100.00%   100.00%     13.75us ( +-  10.83% )
>
> Total Samples:3, Total events handled time:41.26us.
>
> 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         27    13.85%    99.97% 405790.24us ( +-  12.70% )
>    EXTERNAL_INTERRUPT         13     6.67%     0.00%     27.94us ( +-  22.26% )
>           APIC_ACCESS        146    74.87%     0.03%     21.69us ( +-   2.91% )
>        IO_INSTRUCTION          2     1.03%     0.00%     17.77us ( +-  20.56% )
>             CR_ACCESS          2     1.03%     0.00%      8.55us ( +-   6.47% )
>     PENDING_INTERRUPT          5     2.56%     0.00%      6.27us ( +-   3.94% )
>
> Total Samples:195, Total events handled time:10959950.90us.
>
> [ Dong Hao <haodong@linux.vnet.ibm.com>
>    Runzhen Wang <runzhen@linux.vnet.ibm.com>:
>
>       - rebase it on current acme's tree
>
>       - fix the compiling-error on i386
>
> ]
>
> Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
> Signed-off-by: Dong Hao <haodong@linux.vnet.ibm.com>
> Signed-off-by: Runzhen Wang <runzhen@linux.vnet.ibm.com>
> ---
>   tools/perf/Documentation/perf-kvm.txt |   30 ++-
>   tools/perf/MANIFEST                   |    3 +
>   tools/perf/builtin-kvm.c              |  840 ++++++++++++++++++++++++++++++++-
>   tools/perf/util/header.c              |   59 +++-
>   tools/perf/util/header.h              |    1 +
>   tools/perf/util/thread.h              |    2 +
>   6 files changed, 929 insertions(+), 6 deletions(-)
>

Acked-by: David Ahern <dsahern@gmail.com>