perf top: Add --percentage option

The --percentage option is for controlling overhead percentage
displayed.  It can only receive either of "relative" or "absolute".
Move the parser callback function into a common location since it's
used by multiple commands now.

For more information, please see previous commit same thing done to
"perf report".

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1397145720-8063-4-git-send-email-namhyung@kernel.org
Signed-off-by: Jiri Olsa <jolsa@redhat.com>

1 files changed, 15 insertions, 3 deletions

diff --git a/tools/perf/Documentation/perf-top.txt b/tools/perf/Documentation/perf-top.txt
index 976b00c6cdb1..64ed79c43639 100644
--- a/tools/perf/Documentation/perf-top.txt
+++ b/tools/perf/Documentation/perf-top.txt
@@ -123,13 +123,16 @@ Default is to monitor all CPUS.
         Show a column with the sum of periods.
 
 --dsos::
-        Only consider symbols in these dsos.
+        Only consider symbols in these dsos.  This option will affect the
+        percentage of the overhead column.  See --percentage for more info.
 
 --comms::
-        Only consider symbols in these comms.
+        Only consider symbols in these comms.  This option will affect the
+        percentage of the overhead column.  See --percentage for more info.
 
 --symbols::
-        Only consider these symbols.
+        Only consider these symbols.  This option will affect the
+        percentage of the overhead column.  See --percentage for more info.
 
 -M::
 --disassembler-style=:: Set disassembler style for objdump.
@@ -165,6 +168,15 @@ Default is to monitor all CPUS.
         Do not show entries which have an overhead under that percent.
         (Default: 0).
 
+--percentage::
+        Determine how to display the overhead percentage of filtered entries.
+        Filters can be applied by --comms, --dsos and/or --symbols options and
+        Zoom operations on the TUI (thread, dso, etc).
+
+        "relative" means it's relative to filtered entries only so that the
+        sum of shown entries will be always 100%. "absolute" means it retains
+        the original value before and after the filter is applied.
+
 INTERACTIVE PROMPTING KEYS
 --------------------------