• A
    perf kvm: Fix 'Min time' counting in report command · acb61fc8
    Alexander Yarygin 提交于
    Every event in the perf-kvm has a 'stats' structure, which contains
    max/min/average/etc times of handling this event.
    The problem is that the 'perf-kvm stat report' command always shows
    that 'min time' is 0us for every event. Example:
    
     # perf kvm stat report
    
     Analyze events for all VCPUs:
    
        VM-EXIT    Samples  Samples%     Time%   Min Time   Max Time Avg time
      [..]
      0xB2 MSCH         12     0.07%     0.00%        0us        8us 7.31us ( +-   2.11% )
      0xB2 CHSC         12     0.07%     0.00%        0us       18us 9.39us ( +-   9.49% )
      0xB2 STPX          8     0.05%     0.00%        0us        2us 1.88us ( +-   7.18% )
      0xB2 STSI          7     0.04%     0.00%        0us       44us 16.49us ( +-  38.20% )
      [..]
    
    This happens because the 'stats' structure is not initialized and
    stats->min equals to 0. Lets initialize the structure for every
    event after its allocation using init_stats() function. This initializes
    stats->min to -1 and makes 'Min time' statistics counting work:
    
     # perf kvm stat report
    
     Analyze events for all VCPUs:
    
        VM-EXIT    Samples  Samples%     Time%   Min Time   Max Time Avg time
      [..]
      0xB2 MSCH         12     0.07%     0.00%        6us        8us 7.31us ( +-   2.11% )
      0xB2 CHSC         12     0.07%     0.00%        7us       18us 9.39us ( +-   9.49% )
      0xB2 STPX          8     0.05%     0.00%        1us        2us 1.88us ( +-   7.18% )
      0xB2 STSI          7     0.04%     0.00%        1us       44us 16.49us ( +-  38.20% )
      [..]
    Signed-off-by: NAlexander Yarygin <yarygin@linux.vnet.ibm.com>
    Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
    Reviewed-by: NDavid Ahern <dsahern@gmail.com>
    Link: http://lkml.kernel.org/r/1397053319-2130-3-git-send-email-borntraeger@de.ibm.com
    [ Fixing the perf examples changelog output ]
    Signed-off-by: NJiri Olsa <jolsa@redhat.com>
    acb61fc8
builtin-kvm.c 39.3 KB