perf report: Add documentation for dynamic sort keys

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1451991518-25673-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt
index ae7cd91..8a301f6 100644 (file)
--- a/tools/perf/Documentation/perf-report.txt
+++ b/tools/perf/Documentation/perf-report.txt
@@ -117,6 +117,30 @@ OPTIONS
        And default sort keys are changed to comm, dso_from, symbol_from, dso_to
        and symbol_to, see '--branch-stack'.
 
+       If the data file has tracepoint event(s), following (dynamic) sort keys
+       are also available:
+       trace, trace_fields, [<event>.]<field>[/raw]
+
+       - trace: pretty printed trace output in a single column
+       - trace_fields: fields in tracepoints in separate columns
+       - <field name>: optional event and field name for a specific field
+
+       The last form consists of event and field names.  If event name is
+       omitted, it searches all events for matching field name.  The matched
+       field will be shown only for the event has the field.  The event name
+       supports substring match so user doesn't need to specify full subsystem
+       and event name everytime.  For example, 'sched:sched_switch' event can
+       be shortened to 'switch' as long as it's not ambiguous.  Also event can
+       be specified by its index (starting from 1) preceded by the '%'.
+       So '%1' is the first event, '%2' is the second, and so on.
+
+       The field name can have '/raw' suffix which disables pretty printing
+       and shows raw field value like hex numbers.  The --raw-trace option
+       has the same effect for all dynamic sort keys.
+
+       The default sort keys are changed to 'trace' if all events in the data
+       file are tracepoint.
+
 -F::
 --fields=::
        Specify output field - multiple keys can be specified in CSV format.