On 4/9/14, 7:21 AM, Christian Borntraeger wrote:
From: Alexander Yarygin <yary...@linux.vnet.ibm.com>

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 'stats' structure is not initialized and
stats->min equals to 0. Lets initialize the structure for every
event after it's allocation using init_stats() function. This initialize
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: Alexander Yarygin <yary...@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntrae...@de.ibm.com>
---
  tools/perf/builtin-kvm.c |    1 +
  1 file changed, 1 insertion(+)

diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c
index 21c164b..0f1e5a2 100644
--- a/tools/perf/builtin-kvm.c
+++ b/tools/perf/builtin-kvm.c
@@ -404,6 +404,7 @@ static struct kvm_event *kvm_alloc_init_event(struct 
event_key *key)
        }

        event->key = *key;
+       init_stats(&event->total.stats);
        return event;
  }

Reviewed-by: David Ahern <dsah...@gmail.com>


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