perf tools: Recalc total periods using top-level entries in hierarchy
When hierarchy mode is enabled, each entry in a hierarchy level shares the period. IOW an upper level entry's period is the sum of lower level entries. Thus perf uses only one of them to calculate the total period of hists. It was lowest-level (leaf) entries but it has a problem when it comes to filters. If a filter is applied, entries in the same level will be filtered or not. But upper level entries still have period of their sum including filtered one. So total sum of upper level entries will not be same as sum of lower level entries. This resulted in entries having more than 100% of overhead and it can be produced using perf top with filter(s). Reported-and-Tested-by:Jiri Olsa <jolsa@kernel.org> Signed-off-by:
Namhyung Kim <namhyung@kernel.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: David Ahern <dsahern@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/1457531222-18130-8-git-send-email-namhyung@kernel.org Signed-off-by:
Arnaldo Carvalho de Melo <acme@redhat.com>
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