perf stat: Fix interval output values
commit 51fd2df1 upstream. We broke interval data displays with commit: 3f416f22 ("perf stat: Do not clean event's private stats") This commit removed stats cleaning, which is important for '-r' option to carry counters data over the whole run. But it's necessary to clean it for interval mode, otherwise the displayed value is avg of all previous values. Before: $ perf stat -e cycles -a -I 1000 record # time counts unit events 1.000240796 75,216,287 cycles 2.000512791 107,823,524 cycles $ perf stat report # time counts unit events 1.000240796 75,216,287 cycles 2.000512791 91,519,906 cycles Now: $ perf stat report # time counts unit events 1.000240796 75,216,287 cycles 2.000512791 107,823,524 cycles Notice the second value being bigger (91,.. < 107,..). This could be easily verified by using perf script which displays raw stat data: $ perf script CPU THREAD VAL ENA RUN TIME EVENT 0 -1 23855779 1000209530 1000209530 1000240796 cycles 1 -1 33340397 1000224964 1000224964 1000240796 cycles 2 -1 15835415 1000226695 1000226695 1000240796 cycles 3 -1 2184696 1000228245 1000228245 1000240796 cycles 0 -1 97014312 2000514533 2000514533 2000512791 cycles 1 -1 46121497 2000543795 2000543795 2000512791 cycles 2 -1 32269530 2000543566 2000543566 2000512791 cycles 3 -1 7634472 2000544108 2000544108 2000512791 cycles The sum of the first 4 values is the first interval aggregated value: 23855779 + 33340397 + 15835415 + 2184696 = 75,216,287 The sum of the second 4 values minus first value is the second interval aggregated value: 97014312 + 46121497 + 32269530 + 7634472 - 75216287 = 107,823,524 Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1454485436-20639-1-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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