aboutsummaryrefslogtreecommitdiff
path: root/tools/perf/builtin-annotate.c
diff options
context:
space:
mode:
authorIan Rogers <irogers@google.com>2021-12-23 10:56:22 -0800
committerArnaldo Carvalho de Melo <acme@redhat.com>2022-02-15 17:15:33 -0300
commit87a73bdc421ac702c248002a0a2e62f08c6e7682 (patch)
tree017df856afa33bc346462b180a243c15f0cbf9b6 /tools/perf/builtin-annotate.c
parentaca8af3c2e8cb57662e6035c0ccb3c111a11d97a (diff)
downloadlinux-87a73bdc421ac702c248002a0a2e62f08c6e7682.tar.gz
linux-87a73bdc421ac702c248002a0a2e62f08c6e7682.tar.bz2
linux-87a73bdc421ac702c248002a0a2e62f08c6e7682.zip
perf test: Make metric testing more robust
When testing metric expressions we fake counter values from 1 going upward. For some metrics this can yield negative values that are clipped to zero, and then cause divide by zero failures. Such clipping is questionable but may be a result of tools automatically generating metrics. A workaround for this case is to try a second time with counter values going in the opposite direction. This case was seen in a metric like: event1 / max(event2 - event3, 0) But it may also happen in more sensible metrics like: event1 / (event2 + event3 - 1 - event4) Reviewed-by: John Garry <john.garry@huawei.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: https://lore.kernel.org/r/20211223185622.3435128-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/builtin-annotate.c')
0 files changed, 0 insertions, 0 deletions