perf config: Document 'hist.percentage' variable in man page

Explain 'hist.percentage' variable.

Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1452253193-30502-7-git-send-email-treeze.taeung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/Documentation/perf-config.txt b/tools/perf/Documentation/perf-config.txt
index cb7ca50..74589c6 100644 (file)
--- a/tools/perf/Documentation/perf-config.txt
+++ b/tools/perf/Documentation/perf-config.txt
@@ -279,6 +279,23 @@ annotate.*::
 
                99.93 │      mov    %eax,%eax
 
+hist.*::
+       hist.percentage::
+               This option control the way to calculate overhead of filtered entries -
+               that means the value of this option is effective only if there's a
+               filter (by comm, dso or symbol name). Suppose a following example:
+
+                      Overhead  Symbols
+                      ........  .......
+                       33.33%     foo
+                       33.33%     bar
+                       33.33%     baz
+
+              This is an original overhead and we'll filter out the first 'foo'
+              entry. The value of 'relative' would increase the overhead of 'bar'
+              and 'baz' to 50.00% for each, while 'absolute' would show their
+              current overhead (33.33%).
+
 SEE ALSO
 --------
 linkperf:perf[1]